Science.gov

Sample records for future planetary x-ray

  1. Planetary X-ray studies: past, present and future

    NASA Astrophysics Data System (ADS)

    Branduardi-Raymont, Graziella

    2016-07-01

    Our solar system is a fascinating physics laboratory and X-ray observations are now firmly established as a powerful diagnostic tool of the multiple processes taking place in it. The science that X-rays reveal encompasses solar, space plasma and planetary physics, and the response of bodies in the solar system to the impact of the Sun's activity. This talk will review what we know from past observations and what we expect to learn in the short, medium and long term. Observations with Chandra and XMM-Newton have demonstrated that the origin of Jupiter's bright soft X-ray aurorae lies in the Charge eXchange (CX) process, likely to involve the interaction with atmospheric neutrals of local magnetospheric ions, as well as those carried in the solar wind. At higher energies electron bremsstrahlung is thought to be the X-ray emitting mechanism, while the whole planetary disk acts as a mirror for the solar X-ray flux via Thomson and fluorescent scattering. This 'X-ray mirror' phenomenon is all that is observed from Saturn's disk, which otherwise lacks X-ray auroral features. The Earth's X-ray aurora is bright and variable and mostly due to electron bremsstrahlung and line emission from atmospheric species. Un-magnetised planets, Venus and Mars, do not show X-ray aurorae but display the interesting combination of mirroring the solar X-ray flux and producing X-rays by Solar Wind Charge eXchange (SWCX) in their exospheres. These processes respond to different solar stimulation (photons and solar wind plasma respectively) hence their relative contributions are seen to vary according to the Sun's output. Present and future of planetary X-ray studies are very bright. We are preparing for the arrival of the Juno mission at Jupiter this summer and for coordinated observations with Chandra and XMM-Newton on the approach and later during Juno's orbital phase. These will allow direct correlation of the local plasma conditions with the X-ray emissions and the establishment of the

  2. Planetary X ray experiment

    NASA Technical Reports Server (NTRS)

    Anderson, K. A.

    1972-01-01

    Design studies for an X-ray experiment using solid state detectors and for an experiment using a proportional counter for investigating Jovian and Saturnian magnetospheres are reported. Background counting rates through the forward aperture and leakage fluxes are discussed for each design. It is concluded that the best choice of instrument appears to have following the characteristics: (1) two separate multiwire proportional counters for redundancy; (2) passive collimation to restrict the field to about 5 deg, wiregrid modulation collimation to about 0.1 deg angular resolution; (3) no active shielding system around the counter body; and (4) light passive shielding around any portion of the counter body exposed to space to absorb most of the cosmic X-ray background.

  3. Planetary Observations in the Soft X-ray band; Present status and Future CMOS based technology

    NASA Astrophysics Data System (ADS)

    Kenter, A.; Kraft, R.; Murray, S.; Smith, R.; George, F.; Branduardi-Raymont, G.; Roediger, E.; Forman, W.; Elvis, M.

    2013-12-01

    Virtually every object in the Solar system emits X-rays, and X-ray studies of these objects often provides information that cannot be obtained by observations in other bands. The Solar Wind Charge Exchange (SWX) has revealed the nature and constituents of everything from comets, to the magnetosphere of the Earth and the gas giants. X-ray fluorescence observations of atmosphere-less rocky bodies have revealed their surface composition and gross morphology. Existing data, however, have been limited by observations with state of the art Earth-orbiting telescopes (e.g. Chandra, XMM-Newton, and Suzaku) or in-situ instruments with limited capabilities. We are developing CMOS imaging detectors optimized for use as soft x-ray imaging spectrometers. These devices, when coupled to a light-weight focusing optic or mechanical collimator, would be ideal for examining X-ray emission within the Solar System with unprecedented spatial, spectral and temporal resolution. CMOS devices, apart from their observational capabilities, would be ideal for a planetary mission as they consume very little power (~mW) and require only modest cooling. Furthermore, CMOS devices, unlike conventional CCDs, are extremely radiation hard (>5MRad) and could withstand even the hostile radiation environment of a Jovian orbit with little or no performance degradation. The devices can also be read at high (hundreds to thousands of frames per second) frame rates at low noise, a critical requirement given the high count rates (thousands of cts per second). Our CMOS imaging detectors are back thinned and optimized to detect very soft X-ray emission from light elements such as C,N,O,P,S as well as emission from higher Z elements such as Fe and Ti. This sensor can also resolve the strong CX emission lines of O present is the magnetospheric X-ray emission of the gas giants, as well as thermal and non-thermal bremsstrahlung. We could also detect and study the temporal evolution X-ray synchrotron emission from

  4. Optimizing Focusing X-Ray Optics for Planetary Science Applications

    NASA Astrophysics Data System (ADS)

    Melso, Nicole; Romaine, Suzanne; Hong, Jaesub; Cotroneo, Vincenzo

    2015-01-01

    X-Ray observations are a valuable tool for studying the composition, formation and evolution of the numerous X-Ray emitting objects in our Solar System. Although there are plenty of useful applications for in situ X-Ray focusing instrumentation, X-Ray focusing optics have never been feasible for use onboard planetary missions due to their mass and cost. Recent advancements in small-scale X-Ray instrumentation have made focusing X-Ray technology more practical and affordable for use onboard in situ spacecraft. Specifically, the technology of a metal-ceramic hybrid material combined with Electroformed Nickel Replication (ENR) holds great promise for realizing lightweight X-ray optics. We are working to optimize these lightweight focusing X-Ray optics for use in planetary science applications. We have explored multiple configurations and geometries that maximize the telescope's effective area and field of view while meeting practical mass and volume requirements. Each configuration was modeled via analytic calculations and Monte Carlo ray tracing simulations and compared to alternative Micro-pore Optics designs. The improved performance of our approach using hybrid materials has many exciting implications for the future of planetary science, X-Ray instrumentation, and the exploration of X-Ray sources in our Solar System.This work was supported in part by the NSF REU and DoD ASSURE programs under NSF grant no. 1262851 and by the Smithsonian Institution.

  5. X-Ray Observations of Planetary Nebulae

    NASA Astrophysics Data System (ADS)

    Guerrero, M. A.; Chu, Y.-H.; Gruendl, R. A.

    2004-07-01

    Planetary nebulae (PNe) are an exciting addition to the zoo of X-ray sources. Recent Chandra and XMM-Newton observations have detected diffuse X-ray emission from shocked fast winds in PN interiors as well as bow-shocks of fast collimated outflows impinging on the nebular envelope. Point X-ray sources associated with PN central stars are also detected, with the soft X-ray (<0.5 keV) emission originating from the photospheres of stars hotter than ˜100,000 K, and the hard X-ray (≫0.5 keV) emission from instability shocks in the fast stellar wind itself or from a low-mass companion's coronal activity. X-ray observations of PNe offer a unique opportunity to directly examine the dynamic effects of fast stellar winds and collimated outflows, and help us understand the formation and evolution of PNe.

  6. From the Moon to NEAR and Beyond: Developing future remote X-ray spectrometry tools for planetary exploration

    NASA Astrophysics Data System (ADS)

    Clark, P. E.; Murphy, M. E.; McClanahan, T. P.

    2000-10-01

    Scientific results from current work combined with technological developments in instrumentation and computing are advancing the use of X-ray spectrometry for remote planetary exploration. Remote X-ray spectrometry now plays a key role in the exploration of: 1) the Moon, the intended target of the ESA Smart-1 mission; 2) the large, S-class asteroid Eros, now the target of the NEAR mission; and 3) Mercury, the intended target of the Messenger mission. Missions have also been proposed for other small bodies. At present, primary requirements for remote X-ray spectrometry are: 1) The target has little or no atmosphere. 2) An X-ray source, generally the sun, is monitored onboard. 3) The source generates a sufficient signal/noise. This constraint is much less stringent for the intrinsically low cosmic ray induced background solid state detectors which are now replacing proportional counters. 3) The spacecraft trajectory has readily deducible target viewing geometries. Detailed knowledge of the source, spacecraft, target body, footprint positions and characteristics (e.g., roughness, degree of illumination, shadowing), as well as adequate (and possibly lengthy) signal integration times must be available. This necessitates more careful determination of acceptable trade-offs in spacecraft and instrument pointing capability, tracking frequency, fuel for active pointing, and cost than allowed by exclusively cheaper/ faster/ better approaches. Considerable improvements in data handling have resulted from our recent experience with large data volume and complex viewing geometries, including: 1) high speed interactive graphics capability for near real-time data monitoring; 2) the integration of models for source X-ray production with spatial information and real-time observations; 3) the incorporation of recently released high energy spectral analysis packages with background removal and peak detection assumptions that are flexible enough to be appropriate; and 4) the

  7. Future x-ray missions

    NASA Astrophysics Data System (ADS)

    Mushotzky, Richard F.

    2002-11-01

    Recent results from XMM-Newton and Chandra show that sufficiently sensitive x_ray imaging and spectroscopic capabilities allow one to observe the evolution of active galaxies out to z ~ 6, the x-ray signature of luminous star forming galaxies at z~3, as well as the origin and evolution of cosmic structure. With the advent of new optical/UV/IR and radio capabilities in the next decade, it is appropriate to evaluate the future capabilities of planned x-ray missions (e.g., Constellation_X and Astro-E2) as well as other missions being developed (e.g., Gen-X, XEUS, and Astro-G) or under advance planning (MAXIM and EXIST). I will present a summary of the present status of the field and the capabilities of these missions for extragalactic x-ray astronomy.

  8. Instrument report: Planetary X-ray experiment

    NASA Technical Reports Server (NTRS)

    Anderson, K. A.

    1972-01-01

    Design studies for an X-ray experiment to investigate planetary magnetospheres using solid state detectors, or proportional counters are reported. The detectors, background counting rate, and leakage fluxes are discussed. It is concluded that the best choice of instruments appears to be two separate multiproportional counters for redundancy.

  9. Planetary X-rays: Relationship with solar X-rays and solar wind

    NASA Astrophysics Data System (ADS)

    Bhardwaj, A.

    Recently X-ray flares are observed from the low-latitude disk of giant planets Jupiter and Saturn in the energy range of 0.2-2 keV. These flares are found to occur in tandem with the occurrence of solar X-ray flare, when light travel time delay is accounted. These studies suggest that disk of outer planets Jupiter and Saturn acts as "diffuse mirror" for solar X-rays and that X-rays from these planets can be used to study flaring on the hemisphere of the Sun that in invisible to near-Earth space weather satellites. Also by proper modeling of the observed planetary X-rays the solar soft X-ray flux can be derived. X-ray flares are also observed on the Mars. On the other hand, X-rays from comets are produced mainly in charge exchange interaction between highly ionized heavy solar wind ions and cometary neutrals. Thus cometary X-rays provide a diagnostics of the solar wind properties. X-rays from Martian exosphere is also dominantly produced via charge exchange interaction between Martian corona and solar wind, providing proxy for solar wind. This paper provides a brief overview on the X-rays from some of the planets and comets and their connection with solar X-rays and solar wind, and how planetary X-rays can be used to study the Sun.

  10. Silicon carbide X-ray detectors for planetary exploration

    NASA Astrophysics Data System (ADS)

    Lees, J. E.; Bassford, D. J.; Bunce, E. J.; Sims, M. R.; Horsfall, A. B.

    2009-06-01

    Planetary exploration places high demands on instrumentation and presents some of the harshest operating environments and constraints known, including extreme thermal conditions, high-radiation tolerance and the need for low mass and power. We present data on a novel X-ray detector, the Semi-Transparent SiC Schottky Diode (STSSD), which shows promising energy resolution (1.3 keV Full-Width Half-Maximum at 5.9 keV) at room temperature and good radiation tolerance to proton irradiation (with a dose of ˜1013 cm-2, energy ˜50 MeV) with some degradation in resolution to 2.5 keV. Future development of SiC detectors will lead, in principle, to X-ray imaging spectroscopic arrays capable of meeting the stringent demands of future planetary exploration missions. We outline the detector requirements necessary for use in the environment likely to be encountered in a mission to the Jovian system, which has the harshest radiation environment of all the planetary magnetospheres.

  11. The future in X-ray surveys

    NASA Astrophysics Data System (ADS)

    Hasinger, Günther

    2015-08-01

    I will chair this "Way Forward" discusson about the future in X-ray Surveys at the Focus Meeting #6Cosmological X-ray Surveys: probing the Hot and Energetic Cosmos. Participants will be R. Gilli,G. Pratt, G. Fabbiano, X. Barcons, T. Ohashi, F. Harrison.

  12. X-ray observations of planetary nebulae with binary nuclei

    NASA Technical Reports Server (NTRS)

    Apparao, K. M. V.; Berthiaume, G. D.; Nousek, J. A.

    1992-01-01

    Einstein and EXOSAT satellite observations of X-ray emission from the planetary nebulae A63 and LoTr 5 are reviewed. Both of these systems contain binary central stars. No flux was detected from A63 (central star UU Sge). LoTr 5 (central star IN Com) is a previously unreported X-ray emitter; it showed no statistically significant X-ray variability. Three models for the source of the X-ray emission in such systems are considered in the light of these and previous results.

  13. Remote X-Ray Diffraction and X-Ray Fluorescence Analysis on Planetary Surfaces

    NASA Technical Reports Server (NTRS)

    Blake, David F.; DeVincenzi, D. (Technical Monitor)

    1999-01-01

    The legacy of planetary X-ray Diffraction (XRD) and X-ray Fluorescence (XRF) began in 1960 when W. Parish proposed an XRD instrument for deployment on the moon. The instrument was built and flight qualified, but the Lunar XRD program was cancelled shortly before the first human landing in 1969. XRF chemical data have been collected in situ by surface landers on Mars (Viking 1 & 2, Pathfinder) and Venus (Venera 13 & 14). These highly successful experiments provide critical constraints on our current understanding of surface processes and planetary evolution. However, the mineralogy, which is more critical to planetary surface science than simple chemical analysis, will remain unknown or will at best be imprecisely constrained until X-ray diffraction (XRD) data are collected. Recent progress in X-ray detector technology allows the consideration of simultaneous XRD (mineralogic analysis) and high-precision XRF (elemental analysis) in systems miniaturized to the point where they can be mounted on fixed landers or small robotic rovers. There is a variety of potential targets for XRD/XRF equipped landers within the solar system, the most compelling of which are the poles of the moon, the southern highlands of Mars and Europa.

  14. Measuring and interpreting X-ray fluorescence from planetary surfaces.

    PubMed

    Owens, Alan; Beckhoff, Burkhard; Fraser, George; Kolbe, Michael; Krumrey, Michael; Mantero, Alfonso; Mantler, Michael; Peacock, Anthony; Pia, Maria-Grazia; Pullan, Derek; Schneider, Uwe G; Ulm, Gerhard

    2008-11-15

    As part of a comprehensive study of X-ray emission from planetary surfaces and in particular the planet Mercury, we have measured fluorescent radiation from a number of planetary analog rock samples using monochromatized synchrotron radiation provided by the BESSY II electron storage ring. The experiments were carried out using a purpose built X-ray fluorescence (XRF) spectrometer chamber developed by the Physikalisch-Technische Bundesanstalt, Germany's national metrology institute. The XRF instrumentation is absolutely calibrated and allows for reference-free quantitation of rock sample composition, taking into account secondary photon- and electron-induced enhancement effects. The fluorescence data, in turn, have been used to validate a planetary fluorescence simulation tool based on the GEANT4 transport code. This simulation can be used as a mission analysis tool to predict the time-dependent orbital XRF spectral distributions from planetary surfaces throughout the mapping phase.

  15. Be/X-ray Binary Science for Future X-ray Timing Missions

    NASA Technical Reports Server (NTRS)

    Wilson-Hodge, Colleen A.

    2011-01-01

    For future missions, the Be/X-ray binary community needs to clearly define our science priorities for the future to advocate for their inclusion in future missions. In this talk, I will describe current designs for two potential future missions and Be X-ray binary science enabled by these designs. The Large Observatory For X-ray Timing (LOFT) is an X-ray timing mission selected in February 2011 for the assessment phase from the 2010 ESA M3 call for proposals. The Advanced X-ray Timing ARray (AXTAR) is a NASA explorer concept X-ray timing mission. This talk is intended to initiate discussions of our science priorities for the future.

  16. Remote analysis of planetary soils: X-ray diffractometer development

    NASA Technical Reports Server (NTRS)

    Gregory, J. C.

    1973-01-01

    A system is described suitable for remote low power mineralogical analysis of lunar, planetary, or asteroid soils. It includes an X-ray diffractometer, fluorescence spectrometer, and sample preparation system. A one Curie Fe-55 source provides a monochromatic X-ray beam of 5.9 keV. Seeman-Bohlin or focusing geometry is employed in the camera, allowing peak detection to proceed simultaneously at all angles and obviating the need for moving parts. The detector system is an array of 500-600 proportional counters with a wire-spacing of 1 mm. An electronics unit comprising preamplifier, postamplifier, window discriminators, and storage flipflops requiring only 3.5 milliwatts was designed and tested. Total instrument power is less than 5 watts. Powder diffraction patterns using a flat breadboard multiwire counter were recorded.

  17. X-ray lasing - Future directions

    NASA Astrophysics Data System (ADS)

    1985-11-01

    The LLNL program for refining the technology of their current X-ray lasing scheme towards the primary goal of demonstrating amplification at the shortest feasible wavelength is outlined. A better understanding of the physics of the system is sought through the quantitative characterization of ionization balance and inversion kinetics in the exploding-foil X-ray laser targets. A major focus is on optimizing the gain and efficiency of present targets, and on saturating output at about 10 MW per emission line. The investigation of new techniques for producing population inversions includes the development of a multipass X-ray laser cavity. Finally, a variety of applications for the soft-X-ray laser are discussed including measurements of the coherence and divergence of the laser beam, the generation of holographic images, and X-ray microscopy.

  18. The Future of X-Ray Optics

    NASA Technical Reports Server (NTRS)

    Weisskopf, Martin C.

    2013-01-01

    The most important next step is the development of X-ray optics comparable to (or better than) Chandra in angular resolution that far exceed Chandra s effective area. Use the long delay to establish an adequately funded, competitive technology program along the lines I have recommended. Don't be diverted from this objective, except for Explorer-class missions. Progress in X-ray optics, with emphasis on the angular resolution, is central to the paradigm-shifting discoveries and the contributions of X-ray astronomy to multiwavelength astrophysics over the past 51 years.

  19. Prototyping a Global Soft X-Ray Imaging Instrument for Heliophysics, Planetary Science, and Astrophysics Science

    NASA Technical Reports Server (NTRS)

    Collier, M. R.; Porter, F. S.; Sibeck, D. G.; Carter, J. A.; Chiao, M. P.; Chornay, D. J.; Cravens, T.; Galeazzi, M.; Keller, J. W.; Koutroumpa, D.; hide

    2012-01-01

    We describe current progress in the development of a prototype wide field-of-view soft X-ray imager that employs Lobstereye optics and targets heliophysics, planetary, and astrophysics science. The prototype will provide proof-of-concept for a future flight instrument capable of imaging the entire dayside magnetosheath from outside the magnetosphere. Such an instrument was proposed for the ESA AXIOM mission.

  20. Prototyping a Global Soft X-ray Imaging Instrument for Heliophysics, Planetary Science, and Astrophysics Science

    NASA Technical Reports Server (NTRS)

    Collier, Michael R.; Porter, F. Scott; Sibeck, David G.; Carter, Jenny A.; Chiao, Meng P.; Chornay, Dennis J.; Cravens, Thomas; Galeazzi, Massimiliano; Keller, John W.; Koutroumpa, Dimitra; Kuntz, Kip; Read, Any M.; Robertson, Ina P.; Sembay, Steve; Snowden, Steven; Thomas, Nick

    2012-01-01

    We describe current progress in the development of a prototype wide field-of-view soft X-ray imager that employs Lobster-eye optics and targets heliophysics, planetary, and astrophysics science. The prototype will provide proof-of-concept for a future flight instrument capable of imaging the entire dayside magnetosheath from outside the magnetosphere. Such an instrument was proposed for the FSA AXIOM mission

  1. TOMOX : An X-rays tomographer for planetary exploration

    NASA Astrophysics Data System (ADS)

    Marinangeli, Lucia; Pompilio, Loredana; Chiara Tangari, Anna; Baliva, Antonio; Alvaro, Matteo; Chiara Domeneghetti, Maria; Frau, Franco; Melis, Maria Teresa; Bonanno, Giovanni; Consolata Rapisarda, Maria; Petrinca, Paolo; Menozzi, Oliva; Lasalvia, Vasco; Pirrotta, Simone

    2017-04-01

    The TOMOX instrument has recently been founded under the ASI DC-EOS-2014-309 call. The TOMOX objective is to acquire both X-ray fluorescence and diffraction measurements from a sample in order to: a) achieve its chemical and mineralogical composition; b) reconstruct a 3D tomography of the sample exposed surface; c) give hints regarding the sample age. Nevertheless, this technique has applicability in several disciplines other than planetary geology, especially archaeology. The word 'tomography' is nowadays used for many 3D imaging methods, not just for those based on radiographic projections, but also for a wider range of techniques that yield 3D images. Fluorescence tomography is based on the signal produced on an energy-sensitive detector, generally placed in the horizontal plane at some angle with respect to the incident beam caused by photons coming from fluorescence emission. So far, a number of setups have been designed in order to acquire X-rays fluorescence tomograms of several different sample types. The proposed instrument is based on the MARS-XRD heritage, an ultra miniaturised XRD and XRF instrument developed for the ESA ExoMars mission. The general idea of TOMOX is to distribute both sources and detectors along a moving hemispherical support around the target sample. As a result, both sources move integrally with the detectors while the sample is observed from a fixed position, thus preserving the geometry of observation. In that way, the whole sample surface is imagined and XRD and XRF measurements are acquired continuously along all the scans. We plan to irradiate the target sample with X-rays emitted from 55Fe and 109Cd radioactive sources. 55Fe and 109Cd radioisotopes are commonly used as X-ray sources for analysis of metals in soils and rocks. The excitation energies of 55Fe and 109Cd are 5.9 keV, and 22.1 and 87.9 keV, respectively. Therefore, the elemental analysis ranges are Al to Mn with K lines excited with 55Fe; Ca to Rh, with K lines

  2. The Chandra planetary nebula survey (CHANPLANS). II. X-ray emission from compact planetary nebulae

    SciTech Connect

    Freeman, M.; Kastner, J. H.; Montez, R. Jr.; Balick, B.; Frew, D. J.; De Marco, O.; Parker, Q. A.; Jones, D.; Miszalski, B.; Sahai, R.; Blackman, E.; Frank, A.; Chu, Y.-H.; Guerrero, M. A.; Zijlstra, A.; Bujarrabal, V.; Corradi, R. L. M.; Nordhaus, J.; and others

    2014-10-20

    We present results from the most recent set of observations obtained as part of the Chandra X-ray observatory Planetary Nebula Survey (CHANPLANS), the first comprehensive X-ray survey of planetary nebulae (PNe) in the solar neighborhood (i.e., within ∼1.5 kpc of the Sun). The survey is designed to place constraints on the frequency of appearance and range of X-ray spectral characteristics of X-ray-emitting PN central stars and the evolutionary timescales of wind-shock-heated bubbles within PNe. CHANPLANS began with a combined Cycle 12 and archive Chandra survey of 35 PNe. CHANPLANS continued via a Chandra Cycle 14 Large Program which targeted all (24) remaining known compact (R {sub neb} ≲ 0.4 pc), young PNe that lie within ∼1.5 kpc. Results from these Cycle 14 observations include first-time X-ray detections of hot bubbles within NGC 1501, 3918, 6153, and 6369, and point sources in HbDs 1, NGC 6337, and Sp 1. The addition of the Cycle 14 results brings the overall CHANPLANS diffuse X-ray detection rate to ∼27% and the point source detection rate to ∼36%. It has become clearer that diffuse X-ray emission is associated with young (≲ 5 × 10{sup 3} yr), and likewise compact (R {sub neb} ≲ 0.15 pc), PNe with closed structures and high central electron densities (n{sub e} ≳ 1000 cm{sup –3}), and is rarely associated with PNe that show H{sub 2} emission and/or pronounced butterfly structures. Hb 5 is one such exception of a PN with a butterfly structure that hosts diffuse X-ray emission. Additionally, two of the five new diffuse X-ray detections (NGC 1501 and NGC 6369) host [WR]-type central stars, supporting the hypothesis that PNe with central stars of [WR]-type are likely to display diffuse X-ray emission.

  3. Fine X-Ray Tomography of Planetary Nebula

    NASA Astrophysics Data System (ADS)

    Kotoku, Jun'ichi

    2002-09-01

    Although PNs have been thus made a stimulating new addition to the X-ray source populations, the X-ray emission mechanisms and the association between X-ray emitting regions and characteristic features observed in other wavelengths have not yet been clarified, and samples of X-ray PNs are still quite limited. To establish the nature of X-ray emitting PNs, observations with a finer spatial resolution are obviously inevitable. Here, to apply brand-new, X-ray-morphology diagnostic for another PNs with finer spatial resolution, and to verify the role of stellar wind which has been critical in the de facto standard model of the X-ray emission mechanism in PNs, we propose to observe the most promising candidate, NGC 4361 with Chandra ACIS-S.

  4. A Team Approach to the Development of Gamma Ray and x Ray Remote Sensing and in Situ Spectroscopy for Planetary Exploration Missions

    NASA Technical Reports Server (NTRS)

    Trombka, J. I.; Floyd, S.; Ruitberg, A.; Evans, L.; Starr, R.; Metzger, A.; Reedy, R.; Drake, D.; Moss, C.; Edwards, B.

    1993-01-01

    An important part of the investigation of planetary origin and evolution is the determination of the surface composition of planets, comets, and asteroids. Measurements of discrete line X-ray and gamma ray emissions from condensed bodies in space can be used to obtain both qualitative and quantitative elemental composition information. The Planetary Instrumentation Definition and Development Program (PIDDP) X-Ray/Gamma Ray Team has been established to develop remote sensing and in situ technologies for future planetary exploration missions.

  5. Future Hard X-ray and Gamma-Ray Missions

    NASA Astrophysics Data System (ADS)

    Krawczynski, Henric; Physics of the Cosmos (PCOS) Gamma Ray Science Interest Group (GammaSIG) Team

    2017-01-01

    With four major NASA and ESA hard X-ray and gamma-ray missions in orbit (Swift, NuSTAR, INTEGRAL, and Fermi) hard X-ray and gamma-ray astronomy is making major contributions to our understanding of the cosmos. In this talk, I will summarize the current and upcoming activities of the Physics of the Cosmos Gamma Ray Science Interest Group and highlight a few of the future hard X-ray and gamma-ray mission discussed by the community. HK thanks NASA for the support through the awards NNX14AD19G and NNX16AC42G and for PCOS travel support.

  6. Formation and X-ray emission from hot bubbles in planetary nebulae - II. Hot bubble X-ray emission

    NASA Astrophysics Data System (ADS)

    Toalá, J. A.; Arthur, S. J.

    2016-12-01

    We present a study of the X-ray emission from numerical simulations of hot bubbles in planetary nebulae (PNe). High-resolution, two-dimensional, radiation-hydrodynamical simulations of the formation and evolution of hot bubbles in PNe, with and without thermal conduction, are used to calculate the X-ray emission and study its time-dependence and relationship to the changing stellar parameters. Instabilities in the wind-wind interaction zone produce clumps and filaments in the swept-up shell of nebular material. Turbulent mixing and thermal conduction at the corrugated interface can produce quantities of intermediate temperature and density gas between the hot, shocked wind bubble, and the swept-up photoionized nebular material, which can emit in soft, diffuse X-rays. We use the CHIANTI software to compute synthetic spectra for the models and calculate their luminosities. We find that models both with conduction and those without can produce the X-ray temperatures and luminosities that are in the ranges reported in observations, although the models including thermal conduction are an order of magnitude more luminous than those without. Our results show that at early times the diffuse X-ray emission should be dominated by the contribution from the hot, shocked stellar wind, whereas at later times the nebular gas will dominate the spectrum. We analyse the effect of sampling on the resultant spectra and conclude that a minimum of 200 counts is required to reliably reproduce the spectral shape. Likewise, heavily smoothed surface-brightness profiles obtained from low-count detections of PNe do not provide a reliable description of the spatial distribution of the X-ray-emitting gas.

  7. Planning for future X-ray astronomy missions .

    NASA Astrophysics Data System (ADS)

    Urry, C. M.

    Space science has become an international business. Cutting-edge missions are too expensive and too complex for any one country to have the means and expertise to construct. The next big X-ray mission, Astro-H, led by Japan, has significant participation by Europe and the U.S. The two premier missions currently operating, Chandra and XMM-Newton, led by NASA and ESA, respectively, are thoroughly international. The science teams are international and the user community is International. It makes sense that planning for future X-ray astronomy missions -- and the eventual missions themselves -- be fully integrated on an international level.

  8. Planetary and satellite x ray spectroscopy: A new window on solid-body composition by remote sensing

    NASA Technical Reports Server (NTRS)

    Chenette, D. L.; Wolcott, R. W.; Selesnick, R. S.

    1993-01-01

    The rings and most of the satellites of the outer planets orbit within the radiation belts of their parent bodies. This is an environment with intense fluxes of energetic electrons. As a result, these objects are strong emitters of X-rays. The characteristic X-ray lines from these bodies depend on atomic composition, but they are not sensitive to how the material is arranged in compounds or mixtures. X-ray fluorescence spectral analysis has demonstrated its unique value in the laboratory as a qualitative and quantitative analysis tool. This technique has yet to be fully exploited in a planetary instrument for remote sensing. The characteristic X-ray emissions provide atomic relative abundances. These results are complementary to the molecular composition information obtained from IR, visible, and UV emission spectra. The atomic relative abundances are crucial to understanding the formation and evolution of these bodies. They are also crucial to the proper interpretation of the molecular composition results from the other sensors. The intensities of the characteristic X-ray emissions are sufficiently strong to be measured with an instrument of modest size. Recent developments in X-ray detector technologies and electronic miniaturization have made possible space-flight X-ray imaging and nonimaging spectrometers of high sensitivity and excellent energy resolution that are rugged enough to survive long-duration space missions. Depending on the application, such instruments are capable of resolving elemental abundances of elements from carbon through iron. At the same time, by measuring the bremsstrahlung intensity and energy spectrum, the characteristics of the source electron flux can be determined. We will discuss these concepts, including estimated source strengths, and will describe a small instrument capable of providing this unique channel of information for future planetary missions. We propose to build this instrument using innovative electronics packaging

  9. In Situ Mineralogical Analysis of Planetary Materials Using X-Ray Diffraction and X-Ray Fluorescence

    NASA Technical Reports Server (NTRS)

    Sarrazin, P.; Blake, D.; Vaniman, D.; Chang, Sherwood (Technical Monitor)

    1996-01-01

    Remote observations of Mars have led scientists to believe that its early climate was similar to that of the early Earth, having had abundant liquid water and a dense atmosphere. One of the most fascinating questions of recent times is whether simple bacterial life developed on Mars (as it did on the Earth) during this early element period. Analyses of SNC meteorites have broadened considerably our knowledge of the chemistry of certain types of Martian rocks, underscoring the tantalizing possibility of early hydrothermal systems and even of ancient bacterial life. Detailed analyses of SNC meteorites in Terrestrial laboratories utilize the most sophisticated organic, isotopic and microscopic techniques in existence. Indeed; it is unlikely that the key biogenic indicators used in McKay et al (ibid) could be identified by a remote instrument on the surface of Mars. As a result, it is probable that any robotic search for evidence of an ancient Martian biosphere will have as its focus the identification of key minerals in likely host rocks rather than the direct detection of organic or isotopic biomarkers. Even on a sample return mission, mineralogical screening will be utilized to choose the most likely candidate rocks. X-ray diffraction (XRD) is the only technique that can provide a direct determination of the crystal structures of the phases present within a sample. When many different crystalline phases are present, quantitative analysis is better constrained if used in conjunction with a determination of elemental composition, obtainable by X-ray fluorescence (XRF) using the same X-ray source as for XRD. For planetary surface analysis, a remote instrument combining XRD and XRF could be used for mineralogical characterization of both soils and rocks. We are designing a remote XRD/XRF instrument with this objective in mind. The instrument concept pays specific attention to constraints in sample preparation, weight, volume, power, etc. Based on the geometry of a

  10. X-ray photochemical alteration of planetary samples during in situ micro-XRF analysis

    NASA Astrophysics Data System (ADS)

    Flannery, D. T.; Tuite, M. L., Jr.; Hodyss, R. P.; Allwood, A.; Bhartia, R.; Abbey, W. J.; Williford, K. H.

    2015-12-01

    PIXL (Planetary Instrument for X-ray Lithochemistry; selected for the Mars 2020 mission contact science payload) uses a polycapillary to focus X-rays to a ~100 μm spot on sample surfaces, providing higher spatial resolution, higher X-ray flux, and higher fluorescence counts compared to previously flown planetary XRF instruments. Photochemical changes in organic materials occurring during investigations employing x-rays have been reported, particularly for biological samples examined in synchrotrons (e.g. George et al., J. Synchrotron Radiation, 19:875-876). However, little is known about the effect energies and fluxes typical to micro-XRF instruments may have on the organic molecules that are commonly preserved in rocks and sediments. In particular, it is essential to understand the effect of micro-XRF on organics preserved near surfaces that are later subjected to contact science that focuses on organic geochemistry (e.g. UV Raman/fluorescence instruments). We report results of an investigation in which samples containing organic molecules were exposed to X-ray energies and fluxes typical to micro-XRF. Samples containing alkanes and polycyclic aromatic hydrocarbons were characterized by GC-MS and UV Raman/fluorescence before being subjected to various X-ray energies and fluxes typical of PIXL. Following x-ray irradiation, samples were again characterized by GC-MS and UV Raman/fluorescence in order to characterize photochemical effects.

  11. The Chandra Planetary Nebula Survey (ChanPlaNS). II. X-Ray Emission from Compact Planetary Nebulae

    NASA Astrophysics Data System (ADS)

    Freeman, M.; Montez, R., Jr.; Kastner, J. H.; Balick, B.; Frew, D. J.; Jones, D.; Miszalski, B.; Sahai, R.; Blackman, E.; Chu, Y.-H.; De Marco, O.; Frank, A.; Guerrero, M. A.; Lopez, J. A.; Zijlstra, A.; Bujarrabal, V.; Corradi, R. L. M.; Nordhaus, J.; Parker, Q. A.; Sandin, C.; Schönberner, D.; Soker, N.; Sokoloski, J. L.; Steffen, M.; Toalá, J. A.; Ueta, T.; Villaver, E.

    2014-10-01

    We present results from the most recent set of observations obtained as part of the Chandra X-ray observatory Planetary Nebula Survey (ChanPlaNS), the first comprehensive X-ray survey of planetary nebulae (PNe) in the solar neighborhood (i.e., within ~1.5 kpc of the Sun). The survey is designed to place constraints on the frequency of appearance and range of X-ray spectral characteristics of X-ray-emitting PN central stars and the evolutionary timescales of wind-shock-heated bubbles within PNe. ChanPlaNS began with a combined Cycle 12 and archive Chandra survey of 35 PNe. ChanPlaNS continued via a Chandra Cycle 14 Large Program which targeted all (24) remaining known compact (R neb <~ 0.4 pc), young PNe that lie within ~1.5 kpc. Results from these Cycle 14 observations include first-time X-ray detections of hot bubbles within NGC 1501, 3918, 6153, and 6369, and point sources in HbDs 1, NGC 6337, and Sp 1. The addition of the Cycle 14 results brings the overall ChanPlaNS diffuse X-ray detection rate to ~27% and the point source detection rate to ~36%. It has become clearer that diffuse X-ray emission is associated with young (lsim 5 × 103 yr), and likewise compact (R neb <~ 0.15 pc), PNe with closed structures and high central electron densities (ne >~ 1000 cm-3), and is rarely associated with PNe that show H2 emission and/or pronounced butterfly structures. Hb 5 is one such exception of a PN with a butterfly structure that hosts diffuse X-ray emission. Additionally, two of the five new diffuse X-ray detections (NGC 1501 and NGC 6369) host [WR]-type central stars, supporting the hypothesis that PNe with central stars of [WR]-type are likely to display diffuse X-ray emission.

  12. Future X-ray astronomy missions of Japan

    NASA Astrophysics Data System (ADS)

    Inoue, H.; Kunieda, H.

    2004-01-01

    Japanese future space programs for high energy astrophysics are presented. The Astro-E2 mission which is the recovery mission of the lost Astro-E has been approved and now scheduled to be put in orbit in early 2005. The design of the whole spacecraft remains the same as that of Astro-E, except for some improvements in the scientific instruments. In spite of the five years of delay, Astro-E2 is still powerful and timely X-ray mission, because of the high energy resolution spectroscopy (FWHM ˜6 eV in 0.3-10 keV) and high-sensitivity wide-band spectroscopy (0.3-600 keV). The NeXT (New X-ray Telescope) mission, which we propose to have around 2010, succeeds and extends the science which Astro-E2 will open. It will carry five or six sets of X-ray telescopes which utilize super-mirror technology to enable hard X-ray imaging up to ˜60-80 keV. In mid-2010s, we would participate in the European XEUS mission, which explores the early ( z>5) "hot" universe.

  13. Segmented X-Ray Optics for Future Space Telescopes

    NASA Technical Reports Server (NTRS)

    McClelland, Ryan S.

    2013-01-01

    Lightweight and high resolution mirrors are needed for future space-based X-ray telescopes to achieve advances in high-energy astrophysics. The slumped glass mirror technology in development at NASA GSFC aims to build X-ray mirror modules with an area to mass ratio of approx.17 sq cm/kg at 1 keV and a resolution of 10 arc-sec Half Power Diameter (HPD) or better at an affordable cost. As the technology nears the performance requirements, additional engineering effort is needed to ensure the modules are compatible with space-flight. This paper describes Flight Mirror Assembly (FMA) designs for several X-ray astrophysics missions studied by NASA and defines generic driving requirements and subsequent verification tests necessary to advance technology readiness for mission implementation. The requirement to perform X-ray testing in a horizontal beam, based on the orientation of existing facilities, is particularly burdensome on the mirror technology, necessitating mechanical over-constraint of the mirror segments and stiffening of the modules in order to prevent self-weight deformation errors from dominating the measured performance. This requirement, in turn, drives the mass and complexity of the system while limiting the testable angular resolution. Design options for a vertical X-ray test facility alleviating these issues are explored. An alternate mirror and module design using kinematic constraint of the mirror segments, enabled by a vertical test facility, is proposed. The kinematic mounting concept has significant advantages including potential for higher angular resolution, simplified mirror integration, and relaxed thermal requirements. However, it presents new challenges including low vibration modes and imperfections in kinematic constraint. Implementation concepts overcoming these challenges are described along with preliminary test and analysis results demonstrating the feasibility of kinematically mounting slumped glass mirror segments.

  14. Future X-Ray Telescopes: Fresnel Lenses and Interferometry

    NASA Astrophysics Data System (ADS)

    Smith, T. L.; Romaine, S. E.

    2002-12-01

    Science goals are well established for the next generation X-ray observatories, such as Constellation-X1 and Xeus2, which are being planned as followups to the successful Chandra3 and XMM-Newton4, missions which were launched in 1999. Both Constellation-X and Xeus observatories, planned for launch the end of this decade, emphasize large collecting area and high spectral resolution over angular resolution. Hence their angular resolution will not equal the < ~0.5'' of Chandra, the highest angular resolution of any X-ray observatory to date. These missions indicate a new direction for future X-ray observatories: from large general purpose observatories, such as Chandra, to missions with more focused science goals and therefore more tailored designs. Just as Constellation-X and Xeus emphasize throughput and spectral resolution, there are other designs which emphasize imaging with angular resolution surpassing Chandra's already invaluable 0.5''. This will be the emphasis of the missions to follow Constellation-X5. Two of these designs, Fresnel Lenses and X-ray interferometry, present optical systems which, theoretically, can reach micro-arcsecond angular resolutions. Many obstacles have stood in the way of making these designs a reality, but technology is now being developed6 which overcomes these obstacles, opening the door to X-ray imaging at unprecedented resolution. We present basic characteristics of both optical designs as well as the type of science that would benefit most from a milliarcsecond (or better) observatory. 1http://constellation.gsfc.nasa.gov/ 2http://astro.estec.esa.nl/SA-general/Projects/XEUS/ 3http://chandra.harvard.edu/ 4http://sci.esa.int/home/xmm-newton/index.cfm 5http://maxim.gsfc.nasa.gov/ 6Cash, W., Shipley, A., Osterman, S., & Joy, M. 2000, Nature 407, 160 This work was supported in part by NSF grant AST-9731923 to the SAO Summer Intern program.

  15. Metrology Requirements of Future X-Ray Telescopes

    NASA Technical Reports Server (NTRS)

    Gubarev, Mikhail

    2010-01-01

    Fundamental needs for future x-ray telescopes: a) Sharp images => excellent angular resolution. b) High throughput => large aperture areas. Generation-X optics technical challenges: a) High resolution => precision mirrors & alignment. b) Large apertures => lots of lightweight mirrors. Innovation needed for technical readiness: a) 4 top-level error terms contribute to image size. b) There are approaches to controlling those errors. Innovation needed for manufacturing readiness: Programmatic issues are at least as severe

  16. The Born-again Planetary Nebula A78: An X-Ray Twin of A30

    NASA Astrophysics Data System (ADS)

    Toalá, J. A.; Guerrero, M. A.; Todt, H.; Hamann, W.-R.; Chu, Y.-H.; Gruendl, R. A.; Schönberner, D.; Oskinova, L. M.; Marquez-Lugo, R. A.; Fang, X.; Ramos-Larios, G.

    2015-01-01

    We present the XMM-Newton discovery of X-ray emission from the planetary nebula (PN) A78, the second born-again PN detected in X-rays apart from A30. These two PNe share similar spectral and morphological characteristics: they harbor diffuse soft X-ray emission associated with the interaction between the H-poor ejecta and the current fast stellar wind and a point-like source at the position of the central star (CSPN). We present the spectral analysis of the CSPN, using for the first time an NLTE code for expanding atmospheres that takes line blanketing into account for the UV and optical spectra. The wind abundances are used for the X-ray spectral analysis of the CSPN and the diffuse emission. The X-ray emission from the CSPN in A78 can be modeled by a single C VI emission line, while the X-ray emission from its diffuse component is better described by an optically thin plasma emission model with a temperature of kT = 0.088 keV (T ≈ 1.0 × 106 K). We estimate X-ray luminosities in the 0.2-2.0 keV energy band of L X, CSPN = (1.2 ± 0.3) × 1031 erg s-1 and L X, DIFF = (9.2 ± 2.3) × 1030 erg s-1 for the CSPN and diffuse components, respectively.

  17. Demonstration of the feasibility of an integrated x ray laboratory for planetary exploration

    NASA Technical Reports Server (NTRS)

    Franco, E. D.; Kerner, J. A.; Koppel, L. N.; Boyle, M. J.

    1993-01-01

    The identification of minerals and elemental compositions is an important component in the geological and exobiological exploration of the solar system. X ray diffraction and fluorescence are common techniques for obtaining these data. The feasibility of combining these analytical techniques in an integrated x ray laboratory compatible with the volume, mass, and power constraints imposed by many planetary missions was demonstrated. Breadboard level hardware was developed to cover the range of diffraction lines produced by minerals, clays, and amorphous; and to detect the x ray fluorescence emissions of elements from carbon through uranium. These breadboard modules were fabricated and used to demonstrate the ability to detect elements and minerals. Additional effort is required to establish the detection limits of the breadboard modules and to integrate diffraction and fluorescence techniques into a single unit. It was concluded that this integrated x ray laboratory capability will be a valuable tool in the geological and exobiological exploration of the solar system.

  18. Research of nested X-ray concentrator for future X-ray timing astronomy

    NASA Astrophysics Data System (ADS)

    Sheng, Lizhi; Zhao, Baosheng; Qiang, Pengfei; Liu, Duo

    2017-02-01

    X-ray grazing incidence optics are widely used in X-ray astronomy, especially for imaging payloads Wolter optics are the most workhorse. However, as there are two cascaded mirrors in Wolter type, the efficiency is quite low after two reflections. In this paper a kind of nested conical concentrator is developed with only one reflection to concentrate the X-ray photons and obtain the timing information. The mirror length is 200mm, the mirror foils cover from 38.8 to 100mm in diameter. D263T glass of 0.3mm thickness is used as mirror substrate with Iridium film deposited in order to improve the X-ray reflection. The D263T glass is slumped at 580°C with precisely machined and polished mold. 3D printed resin serves as upper mold for glass cutting. The quality of mirror substrate is mainly determined by the surface of forming mandrel. As the surface roughness is quite important for X-ray reflection, after deposition it is tested with interferometer and AFM, and the roughness is 0.6nm. Mirror integration based on visible light is built, and the conical mirrors are assembled and adjusted by real time monitoring for the focal point of visible light. With the monochromic X-ray source, the concentrator efficiency is tested as 38%@1.49keV, 20%@4.51keV. The focal point is Φ8.2mm in Xray, with 80% of its energy encircled in a 4mm width. This kind of X-ray concentrator could be used in X-ray navigation, X-ray communication and other X-ray timing astronomy.

  19. Future of X-Ray Astronomy: X-Ray Polarization of Stellar Mass Black Holes in Close Binary Systems

    NASA Astrophysics Data System (ADS)

    Gnedin, Yu. N.; Piotrovich, M. Yu.

    2017-06-01

    We discuss the perspectives of future polarimetric observations of cosmic objects in the X-ray spectral range. X-ray polarimetry is one of the perspective methods of X-ay astronomy. Since the first discovery of X-ray sources theory predicted a high degree of polarization that could be expected via electron scattering and non-thermal emission mechanisms. X-ray polarimetry is especially important for the X-ray binary systems. The compact objects in these systems are neutron stars, white dwarfs and black holes. Neutron stars and white dwarfs have their intrinsic magnetic fields. But the magnetic field can exist in the accretion disk around a black hole. We demonstrate that the results of the future polarimetric observations in the X-ray range allow to determine the magnetic field strength at the the radius of the innermost stable circular orbit and to determine the value of the black hole spin. The X-ray polarimetry allows also to obtain constraints on the electric charge value of a black hole.

  20. X-Ray Emission Associated with Terrestrial and Planetary Magnetosheath and Cusp Plasma

    NASA Astrophysics Data System (ADS)

    Cravens, Thomas; Walsh, Brian; Kuntz, Kip; Sibeck, David; Collier, Michael; Houston, Stephen; Ozak, Nataly

    2017-04-01

    In situ data from a large number of spacecraft missions, including the recent MMS mission at Earth and the Juno mission at Jupiter, have greatly increased our understanding of processes such as magnetic reconnection at the terrestrial and at planetary magnetopauses. However, still missing from work on these topics are global images of magnetosheath and cusp plasma. Efforts are underway to remedy this deficiency, including the approved ESA-Chinese SMILE mission, which will image magnetosheath and cusp plasma using x-ray emission. The x-rays are produced by charge exchange reactions of high charge state solar wind ions with exospheric neutral gas. Auroral imaging provides another way of obtaining global information relevant to magnetopauses and cusps. For example, the x-ray aurora at Jupiter, observed by the Chandra X-Ray Observatory and XMM-Newton, provide information on magnetosphere-ionosphere coupling at this planet. A general discussion of x-ray emission from planetary magnetospheres will be given in this talk.

  1. Behind the Curtain: Revealing the Nebular Influence on X-ray Emission from Planetary Nebulae

    NASA Astrophysics Data System (ADS)

    Montez, Rodolfo, Jr.

    2017-01-01

    Planetary Nebulae (PNe), the ionized shells of gas surrounding dying low- to intermediate-mass stars, are interesting astrophysical plasma laboratories because of the range of plasma conditions that exist in close proximity. Early in the lifetime of PNe, a 106 K plasma---called a hot bubble---fills the 104 K nebular shell. The interaction of these two plasmas is the potential origin of cooler than expected hot bubble temperatures. Studying high-spatial resolution imaging by the Hubble Space Telescope and the Chandra X-ray Observatory offer an opportunity to study the interaction of these two plasmas. Yet the Chandra and HST observations of PN BD+30°3639 indicate distinct X-ray and optical morphologies that do not appear directly correlated. However, we have developed a method that uses Chandra imaging spectroscopy to study the spatial distribution of the hot bubble X-ray emission. Remarkably, applying this method to the X-ray observation reveals the influence of the surrounding nebula and mimics the optical morphology that is otherwise hidden in the X-ray images. We present the methodology, images derived using the method, and the distribution of the physical conditions that likely give rise to the observed effect. Further improvement of the method and establishing its limitations in the low-count regime will help establish the utility of this method for other low-count extended X-ray sources.

  2. Formation and X-ray emission from hot bubbles in planetary nebulae

    NASA Astrophysics Data System (ADS)

    Toala, J.; Arthur, S. J.

    2014-04-01

    We present 2D radiative-hydrodynamic simulations of the X-ray emission from hot bubbles in planetary nebulae (PNe). We particularly explore the effects of hydrodynamical mixing at the interface between the hot bubble and the cold nebular envelope, and its interplay with thermal conduction in the production of soft X-ray emission. The additional physical processes incorporated in our simulations add fine details to the inner nebular envelope in contact with the hot bubble, having implications on the PN optical morphology which are dependent on the initial stellar mass of the model.

  3. The evolution of planetary nebulae. V. The diffuse X-ray emission

    NASA Astrophysics Data System (ADS)

    Steffen, M.; Schönberner, D.; Warmuth, A.

    2008-10-01

    Context: Observations with space-borne X-ray telescopes revealed the existence of soft, diffuse X-ray emission from the inner regions of planetary nebulae. Although the existing images support the idea that this emission arises from the hot shocked central-star wind which fills the inner cavity of a planetary nebula, existing models have difficulties to explain the observations consistently. Aims: We investigate how the inclusion of thermal conduction changes the physical parameters of the hot shocked wind gas and the amount of X-ray emission predicted by time-dependent hydrodynamical models of planetary nebulae with central stars of normal, hydrogen-rich surface composition. Methods: We upgraded our 1D hydrodynamics code NEBEL by to account for energy transfer due to heat conduction, which is of importance at the interface separating the hot shocked wind gas (“hot bubble”) from the much cooler nebular material. With this new version of NEBEL we recomputed a selection of our already existing hydrodynamical sequences and obtained synthetic X-ray spectra for representative models along the evolutionary tracks by means of the freely available CHIANTI package. Results: Heat conduction leads to lower temperatures and higher densities within a bubble and brings the physical properties of the X-ray emitting domain into close agreement with the values derived from observations. The amount of X-rays emitted during the course of evolution depends on the energy dumped into the bubble by the fast stellar wind, on the efficiency of “evaporating” cool nebular gas via heat conduction, and on the bubble's expansion rate. We find from our models that the X-ray luminosity of a planetary nebula increases during its evolution across the HR diagram until stellar luminosity and wind power decline. Depending on the central-star mass and the evolutionary phase, our models predict X-ray [ 0.45-2.5 keV] luminosities between 10-8 and 10-4 of the stellar bolometric luminosities, in

  4. Full Field X-Ray Fluorescence Imaging Using Micro Pore Optics for Planetary Surface Exploration

    NASA Technical Reports Server (NTRS)

    Sarrazin, P.; Blake, D. F.; Gailhanou, M.; Walter, P.; Schyns, E.; Marchis, F.; Thompson, K.; Bristow, T.

    2016-01-01

    Many planetary surface processes leave evidence as small features in the sub-millimetre scale. Current planetary X-ray fluorescence spectrometers lack the spatial resolution to analyse such small features as they only provide global analyses of areas greater than 100 mm(exp 2). A micro-XRF spectrometer will be deployed on the NASA Mars 2020 rover to analyse spots as small as 120m. When using its line-scanning capacity combined to perpendicular scanning by the rover arm, elemental maps can be generated. We present a new instrument that provides full-field XRF imaging, alleviating the need for precise positioning and scanning mechanisms. The Mapping X-ray Fluorescence Spectrometer - "Map-X" - will allow elemental imaging with approximately 100µm spatial resolution and simultaneously provide elemental chemistry at the scale where many relict physical, chemical and biological features can be imaged in ancient rocks. The arm-mounted Map-X instrument is placed directly on the surface of an object and held in a fixed position during measurements. A 25x25 mm(exp 2) surface area is uniformly illuminated with X-rays or alpha-particles and gamma-rays. A novel Micro Pore Optic focusses a fraction of the emitted X-ray fluorescence onto a CCD operated at a few frames per second. On board processing allows measuring the energy and coordinates of each X-ray photon collected. Large sets of frames are reduced into 2d histograms used to compute higher level data products such as elemental maps and XRF spectra from selected regions of interest. XRF spectra are processed on the ground to further determine quantitative elemental compositions. The instrument development will be presented with an emphasis on the characterization and modelling of the X-ray focussing Micro Pore Optic. An outlook on possible alternative XRF imaging applications will be discussed.

  5. A High Speed, Radiation Hard X-Ray Imaging Spectroscometer for Planetary Investigations

    NASA Technical Reports Server (NTRS)

    Kraft, R. P.; Kenter, A. T.; Murray, S. S.; Martindale, A.; Pearson, J.; Gladstone, R.; Branduardi-Raymont, G.; Elsner, R.; Kimura, T.; Ezoe, Y.; Grant, C.; Roediger, E.; Howell, R.; Elvis, M.; Smith, R.; Campbell, B.; Morgenthaler, J.; Kravens, T.; Steffl, A. J.; Hong, J.

    2014-01-01

    X-ray observations provide a unique window into fundamental processes in planetary physics, and one that is complementary to observations obtained at other wavelengths. We propose to develop an X-ray imaging spectrometer (0.1-10 keV band) that, on orbital planetary missions, would measure the elemental composition, density, and temperature of the hot plasma in gas giant magnetospheres, the interaction of the Solar wind with the upper atmospheres of terrestrial planets, and map the elemental composition of the surfaces of the Galilean moons and rocky or icy airless systems on spatial scales as small as a few meters. The X-ray emission from gas giants, terrestrial planets and moons with atmospheres, displays diverse characteristics that depend on the Solar wind's interaction with their upper atmospheres and/or magnetospheres. Our imaging spectrometer, as part of a dedicated mission to a gas giant, will be a paradigm changing technology. On a mission to the Jovian system, our baseline instrument would map the elemental composition of the rocky and icy surfaces of the Galilean moons via particle-induced X-ray fluorescence. This instrument would also measure the temperature, density and elemental abundance of the thermal plasma in the magnetosphere and in the Io plasma torus (IPT), explore the interaction of the Solar wind with the magnetosphere, and characterize the spectrum, flux, and temporal variability of X-ray emission from the polar auroras. We will constrain both the mode of energy transport and the effective transport coefficients in the IPT and throughout the Jovian magnetosphere by comparing temporal and spatial variations of the X-ray emitting plasma with those seen from the cooler but energetically dominant 5 eV plasma.

  6. THE BORN-AGAIN PLANETARY NEBULA A78: AN X-RAY TWIN OF A30

    SciTech Connect

    Toalá, J. A.; Guerrero, M. A.; Marquez-Lugo, R. A.; Fang, X.; Schönberner, D.; Ramos-Larios, G.

    2015-01-20

    We present the XMM-Newton discovery of X-ray emission from the planetary nebula (PN) A78, the second born-again PN detected in X-rays apart from A30. These two PNe share similar spectral and morphological characteristics: they harbor diffuse soft X-ray emission associated with the interaction between the H-poor ejecta and the current fast stellar wind and a point-like source at the position of the central star (CSPN). We present the spectral analysis of the CSPN, using for the first time an NLTE code for expanding atmospheres that takes line blanketing into account for the UV and optical spectra. The wind abundances are used for the X-ray spectral analysis of the CSPN and the diffuse emission. The X-ray emission from the CSPN in A78 can be modeled by a single C VI emission line, while the X-ray emission from its diffuse component is better described by an optically thin plasma emission model with a temperature of kT = 0.088 keV (T ≈ 1.0 × 10{sup 6} K). We estimate X-ray luminosities in the 0.2-2.0 keV energy band of L {sub X,} {sub CSPN} = (1.2 ± 0.3) × 10{sup 31} erg s{sup –1} and L {sub X,} {sub DIFF} = (9.2 ± 2.3) × 10{sup 30} erg s{sup –1} for the CSPN and diffuse components, respectively.

  7. Planetary Protection: X-ray Super-Flares Aid Formation of "Solar Systems"

    NASA Astrophysics Data System (ADS)

    2005-05-01

    New results from NASA's Chandra X-ray Observatory imply that X-ray super-flares torched the young Solar System. Such flares likely affected the planet-forming disk around the early Sun, and may have enhanced the survival chances of Earth. By focusing on the Orion Nebula almost continuously for 13 days, a team of scientists used Chandra to obtain the deepest X-ray observation ever taken of this or any star cluster. The Orion Nebula is the nearest rich stellar nursery, located just 1,500 light years away. These data provide an unparalleled view of 1400 young stars, 30 of which are prototypes of the early Sun. The scientists discovered that these young suns erupt in enormous flares that dwarf - in energy, size, and frequency -- anything seen from the Sun today. Illustration of Large Flares Illustration of Large Flares "We don't have a time machine to see how the young Sun behaved, but the next best thing is to observe Sun-like stars in Orion," said Scott Wolk of Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. "We are getting a unique look at stars between one and 10 million years old - a time when planets form." A key result is that the more violent stars produce flares that are a hundred times as energetic as the more docile ones. This difference may specifically affect the fate of planets that are relatively small and rocky, like the Earth. "Big X-ray flares could lead to planetary systems like ours where Earth is a safe distance from the Sun," said Eric Feigelson of Penn State University in University Park, and principal investigator for the international Chandra Orion Ultradeep Project. "Stars with smaller flares, on the other hand, might end up with Earth-like planets plummeting into the star." Animation of X-ray Flares from a Young Sun Animation of X-ray Flares from a "Young Sun" According to recent theoretical work, X-ray flares can create turbulence when they strike planet-forming disks, and this affects the position of rocky planets as they

  8. DETECTION OF DIFFUSE X-RAY EMISSION FROM PLANETARY NEBULAE WITH NEBULAR O VI

    SciTech Connect

    Ruiz, N.; Guerrero, M. A.; Jacob, R.; Schoenberner, D.; Steffen, M.

    2013-04-10

    The presence of O VI ions can be indicative of plasma temperatures of a few Multiplication-Sign 10{sup 5} K that are expected in heat conduction layers between the hot shocked stellar wind gas at several 10{sup 6} K and the cooler (10{sup 4} K) nebular gas of planetary nebulae (PNe). We have used FUSE observations of PNe to search for nebular O VI emission or absorption as a diagnostic of the conduction layer to ensure the presence of hot interior gas. Three PNe showing nebular O VI, namely IC 418, NGC 2392, and NGC 6826, have been selected for Chandra observations and diffuse X-ray emission is indeed detected in each of these PNe. Among the three, NGC 2392 has peculiarly high diffuse X-ray luminosity and plasma temperature compared with those expected from its stellar wind's mechanical luminosity and terminal velocity. The limited effects of heat conduction on the plasma temperature of a hot bubble at the low terminal velocity of the stellar wind of NGC 2392 may partially account for its high plasma temperature, but the high X-ray luminosity needs to be powered by processes other than the observed stellar wind, probably the presence of an unseen binary companion of the central star of the PN (CSPN) of NGC 2392. We have compiled relevant information on the X-ray, stellar, and nebular properties of PNe with a bubble morphology and found that the expectations of bubble models including heat conduction compare favorably with the present X-ray observations of hot bubbles around H-rich CSPNe, but have notable discrepancies for those around H-poor [WR] CSPNe. We note that PNe with more massive central stars can produce hotter plasma and higher X-ray surface brightness inside central hot bubbles.

  9. REBIRTH OF X-RAY EMISSION FROM THE BORN-AGAIN PLANETARY NEBULA A30

    SciTech Connect

    Guerrero, M. A.; Ruiz, N.; Toala, J. A.; Chu, Y.-H.; Gruendl, R. A.; Schoenberner, D.; Steffen, M.; Blair, W. P.

    2012-08-20

    The planetary nebula A30 is believed to have undergone a very late thermal pulse resulting in the ejection of knots of hydrogen-poor material. Using multi-epoch Hubble Space Telescope images, we have detected the angular expansion of these knots and derived an age of 850{sup +280}{sub -150} yr. To investigate the spectral and spatial properties of the soft X-ray emission detected by ROSAT, we have obtained Chandra and XMM-Newton deep observations of A30. The X-ray emission from A30 can be separated into two components: a point source at the central star and diffuse emission associated with the hydrogen-poor knots and the cloverleaf structure inside the nebular shell. To help us assess the role of the current stellar wind in powering this X-ray emission, we have determined the stellar parameters and wind properties of the central star of A30 using a non-LTE model fit to its optical and UV spectra. The spatial distribution and spectral properties of the diffuse X-ray emission are highly suggestive that it is generated by the post-born-again and present fast stellar winds interacting with the hydrogen-poor ejecta of the born-again event. This emission can be attributed to shock-heated plasma, as the hydrogen-poor knots are ablated by the stellar winds, under which circumstances the efficient mass loading of the present fast stellar wind raises its density and damps its velocity to produce the observed diffuse soft X-rays. Charge transfer reactions between the ions of the stellar winds and material of the born-again ejecta have also been considered as a possible mechanism for the production of diffuse X-ray emission, and upper limits on the expected X-ray production by this mechanism have been derived. The origin of the X-ray emission from the central star of A30 is puzzling: shocks in the present fast stellar wind and photospheric emission can be ruled out, while the development of a new, compact hot bubble confining the fast stellar wind seems implausible.

  10. Suzaku Reveals He-burning Products in the X-ray Emitting Planetary Nebula BD +30deg 3639

    NASA Technical Reports Server (NTRS)

    Murashima, M.; Kokubun, M.; Makishima, K.; Kotoku, J.; Murakami, H.; Matsushita, K.; Hayashida, K.; Hamaguchi, K.; Matsumoto, H.

    2004-01-01

    BD +30deg 3639, the brightest planetary nebula at X-ray energies, was observed with Suzaku, an X-ray observatory launched on 2005 July 10. Using the X-ray Imaging Spectrometer, the K-lines from C VI, O VII, and O VIII were resolved for the first time, and C/O, N/O, and Ne/O abundance ratios determined. The C/O abundance ratio exceeds the solar value by nearly two orders of magnitude, and that of Ne/O by at least a factor of 5. These results indicate that the X-rays are emitted mainly by helium shell-burning products.

  11. Hard x-rays nanoscale fluorescence imaging of Earth and Planetary science samples

    SciTech Connect

    Bleuet, Pierre; Cloetens, Peter; Tucoulou, Remi; Susini, Jean; Simionovici, Alexandre; Lemelle, Laurence; Ferroir, Tristan

    2008-05-26

    A hard x-ray nanoprobe has been implemented at the synchrotron in Grenoble, France, allowing nondestructive trace element imaging of thick samples. Its advantages are nanometer spatial resolution on samples of several tens of micrometer, very high flux, and achromaticity. Nanometer imaging of a cometary grain from the NASA Stardust mission shows the sensitivity and resolution gains obtained while radically changing our understanding of the composition of heterogeneous samples. The probe opens unique possibilities in the study of minute, fragile samples fundamental to the earth and planetary sciences, which until now were out of the reach of direct analytical methods.

  12. Soft X-ray Shock Loading and Momentum Coupling in Meteorite and Planetary Materials^1

    NASA Astrophysics Data System (ADS)

    Remo, J. L.; Furnish, M. D.; Lawrence, R. J.

    2011-06-01

    X-ray momentum coupling coefficients, CM, for planetary materials were determined by measuring stress waveforms produced by impulsive radiation loading from the SNL Z- machine. Targets were iron and stone meteorites, solid and powdered dunite, and Si, Al, and Fe. All samples were ˜ 1 mm thick and, except for Si, backed by LiF single-crystal windows. The x-ray spectra included thermal radiation (blackbody 170 to 237 eV) and line emissions from the pinch material (Cu, Ni, Al, or stainless steel). Target fluences of 0.4 to 1.7 kJ/cm^2 at intensities 43 to 260 GW/cm^2 produced front surface plasma pressures of 2.6 to 12.4 GPa. Stress waves driven into the samples were attenuating due to the short (˜ 5 ns) duration of the drive pulse. CM was determined using the fact that an attenuating wave impulse is constant, and accounted for the mechanical impedance mismatch between samples and window. Related experiments in the literature are discussed. Values ranged from 0.8 to 3.1 x 10-5 s/m. CTH hydrocode modeling of x-ray coupling to porous and fully dense silica supported the experimental measurements and extrapolations to other materials. ^1 Work supported by Sandia National Labs, operated by Sandia Corp., a wholly owned subsidiary of Lockheed Martin Corp., for the U.S. DOE's NNSA under contract DE-AC04-94AL85000.

  13. Soft X-ray shock loading and momentum coupling in meteorite and planetary materials

    NASA Astrophysics Data System (ADS)

    Remo, J. L.; Furnish, M. D.; Lawrence, R. J.

    2012-03-01

    X-ray momentum coupling coefficients, CM, were determined by measuring stress waveforms in planetary materials subjected to impulsive radiation loading from the SNL Z-machine. Targets were prepared from iron and stone meteorites, dunite (primarily magnesium rich olivine) in solid and powder forms (~5 - 300 μm grains), and Si, Al, and Fe. All samples were ~1 mm thick and, except for Si, backed by LiF single-crystal windows. The spectra of the incident x-rays included thermal radiation (blackbody 170 - 237 eV) and line emissions from the pinch material (Cu, Ni, Al, or stainless steel). Target fluences of 0.4 - 1.7 kJ/cm2 at intensities 43 - 260 GW/cm2 produced front surface plasma pressures of 2.6 - 12.4 GPa. Stress waves driven into the samples were attenuating due to the short ~5 ns duration of the drive pulse. CM was determined using the fact that an attenuating wave impulse is constant, and accounted for the mechanical impedance mismatch between samples and window. Values ranged from 0.8 - 3.1 x 10-5 s/m. CTH hydrocode modeling of x-ray coupling to porous and fully dense silica corroborated experimental results and extrapolations to other materials.

  14. X-Ray Diffraction and Fluorescence Measurements for In-situ Planetary Instruments

    NASA Astrophysics Data System (ADS)

    Hansford, G.; Hill, K. S.; Vernon, D.; Ambrosi, R. M.; Bridges, J.; Hutchinson, I.

    2010-12-01

    The X-Ray Diffraction (XRD) instruments are core components of the forthcoming NASA Mars Science Laboratory (MSL) and ESA/NASA EXOMARS missions and will provide the first demonstrations of an XRF/XRD instrument’s capabilities in-situ on an extraterrestrial planetary surface. The University of Leicester team is part of the Italy-UK collaboration that is responsible for building the ExoMars X-Ray Diffraction instrument, Mars XRD. The ExoMars X-ray diffraction instrument incorporates an 55-Fe radioisotope source and three fixed-position CCDs to simultaneously acquire an X-Ray fluorescence spectrum and a diffraction pattern providing a measurement of both elemental and mineralogical composition [1]. The CCDs cover an angular range from 6 to 65-deg enabling the analysis of silicates, from clays, or other phyllosilicates characterised by varying d-spacings, to oxides, and carbonates or evaporites. The identification of hydrous minerals may help identify past Martian hydrothermal systems capable of preserving traces of life. Here we present some initial findings from XRF and XRD tests carried out at the University of Leicester using an 55-Fe source and X-ray sensitive CCD [1]. The XRD/XRD test system consists of a single CCD on a motorised arm, an 55-Fe X-ray source, source collimator and a sample table which approximately replicate the reflection geometry of the XRD instrument. It was used to test geological reference standard materials and Martian analogues. Incidence angle and CCD angles on both the diffraction and fluorescence results were evaluated. A key area of interest is the effect of sample roughness on the XRD/XRF results. We present results from testing pressed powder pellet samples of varying surface roughness, and a comparison with model results [2]. So far we have found that increased roughness causes a reduced intensity at lower take-off angles. Several methods for measuring surface roughness of the samples have been used including an Alicona Infinite

  15. Novel Hybrid CMOS X-ray Detector Developments for Future Large Area and High Resolution X-ray Astronomy Missions

    NASA Astrophysics Data System (ADS)

    Falcone, Abe

    In the coming years, X-ray astronomy will require new soft X-ray detectors that can be read very quickly with low noise and can achieve small pixel sizes over a moderately large focal plane area. These requirements will be present for a variety of X-ray missions that will attempt to address science that was highly ranked by the 2010 Decadal Survey, including missions with science that overlaps with that of IXO and Athena, as well as other missions addressing science topics beyond those of IXO and Athena. An X-ray Surveyor mission was recently chosen by NASA for study by a Science & Technology Definition Team (STDT) so it can be considered as an option for an upcom-ing flagship mission. A mission such as this was endorsed by the NASA long term planning document entitled "Enduring Quests, Daring Visions," and a detailed description of one possible reali-zation of such a mission has been referred to as SMART-X, which was described in a recent NASA RFI response. This provides an example of a future mission concept with these requirements since it has high X-ray throughput and excellent spatial resolution. We propose to continue to modify current active pixel sensor designs, in particular the hybrid CMOS detectors that we have been working with for several years, and implement new in-pixel technologies that will allow us to achieve these ambitious and realistic requirements on a timeline that will make them available to upcoming X-ray missions. This proposal is a continuation of our program that has been work-ing on these developments for the past several years. The first 3 years of the program led to the development of a new circuit design for each pixel, which has now been shown to be suitable for a larger detector array. The proposed activity for the next four years will be to incorporate this pixel design into a new design of a full detector array (2k×2k pixels with digital output) and to fabricate this full-sized device so it can be thoroughly tested and

  16. Opportunities for X-ray Science in Future Computing Architectures

    SciTech Connect

    Foster, Ian

    2011-02-09

    The world of computing continues to evolve rapidly. In just the past 10 years, we have seen the emergence of petascale supercomputing, cloud computing that provides on-demand computing and storage with considerable economies of scale, software-as-a-service methods that permit outsourcing of complex processes, and grid computing that enables federation of resources across institutional boundaries. These trends show no sign of slowing down. The next 10 years will surely see exascale, new cloud offerings, and other terabit networks. This talk reviews various of these developments and discusses their potential implications for x-ray science and x-ray facilities.

  17. X-Ray Diffraction and Fluorescence Measurements for In Situ Planetary Instruments

    NASA Astrophysics Data System (ADS)

    Hansford, G.; Hill, K. S.; Talboys, D.; Vernon, D.; Ambrosi, R.; Bridges, J.; Hutchinson, I.; Marinangeli, L.

    2011-12-01

    The ESA/NASA ExoMars mission, due for launch in 2018, has a combined X-ray fluorescence/diffraction instrument, Mars-XRD, as part of the onboard analytical laboratory. The results of some XRF (X-ray fluorescence) and XRD (X-ray diffraction) tests using a laboratory chamber with representative performance are reported. A range of standard geological reference materials and analogues were used in these tests. The XRD instruments are core components of the forthcoming NASA Mars Science Laboratory (MSL) and ESA/NASA ExoMars missions and will provide the first demonstrations of the capabilities of combined XRD/XRF instrumentation in situ on an extraterrestrial planetary surface. The University of Leicester team is part of the Italy-UK collaboration that is responsible for building the ExoMars X-ray diffraction instrument, Mars-XRD [1,2]. Mars-XRD incorporates an Fe-55 radioisotope source and three fixed-position charge-coupled devices (CCDs) to simultaneously acquire an X-ray fluorescence spectrum and a diffraction pattern providing a measurement of both elemental and mineralogical composition. The CCDs cover an angular range of 2θ = 6° to 73° enabling the analysis of a wide range of geologically important minerals including phyllosilicates, feldspars, oxides, carbonates and evaporites. The identification of hydrous minerals may help identify past Martian hydrothermal systems capable of preserving traces of life. Here we present some initial findings from XRF and XRD tests carried out at the University of Leicester using an Fe-55 source and X-ray sensitive CCD. The XRF/XRD test system consists of a single CCD on a motorised arm, an Fe-55 X-ray source, a collimator and a sample table which approximately replicate the reflection geometry of the Mars-XRD instrument. It was used to test geological reference standard materials and Martian analogues. This work was funded by the Science and Technology Facilities Council, UK. References [1] Marinangeli, L., Hutchinson, I

  18. THE CHANDRA X-RAY SURVEY OF PLANETARY NEBULAE (CHANPLANS): PROBING BINARITY, MAGNETIC FIELDS, AND WIND COLLISIONS

    SciTech Connect

    Kastner, J. H.; Montez, R. Jr.; Rapson, V.; Balick, B.; Frew, D. J.; De Marco, O.; Parker, Q. A.; Miszalski, B.; Sahai, R.; Blackman, E.; Frank, A.; Chu, Y.-H.; Guerrero, M. A.; Zijlstra, A.; Behar, E.; Bujarrabal, V.; Corradi, R. L. M.; Nordhaus, J.; Sandin, C. E-mail: soker@physics.technion.ac.il; and others

    2012-08-15

    We present an overview of the initial results from the Chandra Planetary Nebula Survey (CHANPLANS), the first systematic (volume-limited) Chandra X-Ray Observatory survey of planetary nebulae (PNe) in the solar neighborhood. The first phase of CHANPLANS targeted 21 mostly high-excitation PNe within {approx}1.5 kpc of Earth, yielding four detections of diffuse X-ray emission and nine detections of X-ray-luminous point sources at the central stars (CSPNe) of these objects. Combining these results with those obtained from Chandra archival data for all (14) other PNe within {approx}1.5 kpc that have been observed to date, we find an overall X-ray detection rate of {approx}70% for the 35 sample objects. Roughly 50% of the PNe observed by Chandra harbor X-ray-luminous CSPNe, while soft, diffuse X-ray emission tracing shocks-in most cases, 'hot bubbles'-formed by energetic wind collisions is detected in {approx}30%; five objects display both diffuse and point-like emission components. The presence (or absence) of X-ray sources appears correlated with PN density structure, in that molecule-poor, elliptical nebulae are more likely to display X-ray emission (either point-like or diffuse) than molecule-rich, bipolar, or Ring-like nebulae. All but one of the point-like CSPNe X-ray sources display X-ray spectra that are harder than expected from hot ({approx}100 kK) central stars emitting as simple blackbodies; the lone apparent exception is the central star of the Dumbbell nebula, NGC 6853. These hard X-ray excesses may suggest a high frequency of binary companions to CSPNe. Other potential explanations include self-shocking winds or PN mass fallback. Most PNe detected as diffuse X-ray sources are elliptical nebulae that display a nested shell/halo structure and bright ansae; the diffuse X-ray emission regions are confined within inner, sharp-rimmed shells. All sample PNe that display diffuse X-ray emission have inner shell dynamical ages {approx}< 5 Multiplication-Sign 10{sup

  19. Current status and future perspectives of accelerator-based x-ray light sources

    NASA Astrophysics Data System (ADS)

    Tanaka, Takashi

    2017-09-01

    State-of-the-art x-ray light sources are nowadays based on large-scale electron accelerators, because the synchrotron radiation (SR) and x-ray free electron laser (XFEL) radiation generated by high-energy electron beams have many advantages over other alternatives in terms of the wavelength tunability, high brightness and flux, high coherence, flexible polarization states, and so on. This is the reason why SR and XFEL light sources have largely contributed to the evolution of x-ray science. This paper reviews the current status of such accelerator-based x-ray light source facilities and discusses their future perspectives.

  20. X-RAY EMISSION FROM THE BINARY CENTRAL STARS OF THE PLANETARY NEBULAE HFG 1, DS 1, AND LOTR 5

    SciTech Connect

    Montez, Rodolfo; Kastner, Joel H.; De Marco, Orsola; Chu, You-Hua

    2010-10-01

    Close binary systems undergoing mass transfer or common envelope interactions can account for the morphological properties of some planetary nebulae. The search for close binary companions in planetary nebulae is hindered by the difficulty of detecting cool, late-type, main-sequence companions in binary systems with hot pre-white-dwarf primaries. However, models of binary planetary nebula progenitor systems predict that mass accretion or tidal interactions can induce rapid rotation in the companion, leading to X-ray-emitting coronae. To test such models, we have searched for, and detected, X-ray emission from three binary central stars within planetary nebulae: the post-common envelope close binaries in HFG 1 and DS 1 consisting of O-type subdwarfs with late-type, main-sequence companions and the binary system in LoTr 5 consisting of O-type subdwarf and rapidly rotating, late-type giant companion. The X-ray emission in each case is best characterized by spectral models consisting of two optically thin thermal plasma components with characteristic temperatures of {approx}10 MK and 15-40 MK and total X-ray luminosities {approx}10{sup 30} erg s{sup -1}. We consider the possible origin of the X-ray emission from these binary systems and conclude that the most likely origin is, in each case, a corona around the late-type companion, as predicted by models of interacting binaries.

  1. Laboratory Tests of a Handheld X-Ray Fluorescence Spectrometer: A Tool for Planetary Exploration

    NASA Astrophysics Data System (ADS)

    Young, K. E.; Evans, C. A.; Hodges, K.

    2011-12-01

    Maximizing the science return from a mission to another planetary surface involves the integration of science objectives with deployable technologies that enable the collection of data and samples. For long duration manned missions, it is likely that more samples will be collected than can be returned to Earth due to mass limits. A niche exists for technologies that help prioritize samples for return, provide data for future sample handling and curation, and characterization for samples that are not returned to Earth. To fill this niche, hardware and protocols for field instruments are currently being developed and evaluated at NASA Johnson Space Center and Arizona State University. Our goal is to develop an easily used, environmentally isolated facility as part of the astronaut surface habitat for preliminary sample characterization and down-selection. NASA has constructed a prototype, GeoLab, as a testbed for evaluating the scientific applicability and operational considerations of various analytical instruments. One instrument under evaluation is a small, portable x-ray fluorescence (XRF) spectrometer that can be also be used by astronaut explorers as part of their field gear while on scientific sorties, or on robotic field assistants. We report on preliminary usability tests for commercially available handheld XRF instruments. These instruments collect data by contacting the surface of a rock or sediment sample with an 8 mm-wide sensor window. Within 60 seconds, the devices can provide relatively precise data on the abundance of major and trace elements heavier than Na. Lab-based handheld XRF analyses of terrestrial and lunar samples, compared with those made with full-scale laboratory XRF systems, show good correlation, but we continue to investigate potential sources of error and the need for careful calibration with standards of known composition. Specifically, we use a suite of five terrestrial and five lunar basalts, all well characterized by conventional

  2. The role of the background in past and future X-ray missions

    NASA Astrophysics Data System (ADS)

    Molendi, Silvano

    2017-09-01

    Background has played an important role in X-ray missions, limiting the exploitation of science data in several and sometimes unexpected ways. In this presentation I review past X-ray missions focusing on some important lessons we can learn from them. I then go on discussing prospects for overcoming background related limitations in future ones.

  3. THE CHANDRA PLANETARY NEBULA SURVEY (ChanPlaNS). III. X-RAY EMISSION FROM THE CENTRAL STARS OF PLANETARY NEBULAE

    SciTech Connect

    Montez, R. Jr.; Kastner, J. H.; Freeman, M.; and others

    2015-02-10

    We present X-ray spectral analysis of 20 point-like X-ray sources detected in Chandra Planetary Nebula Survey observations of 59 planetary nebulae (PNe) in the solar neighborhood. Most of these 20 detections are associated with luminous central stars within relatively young, compact nebulae. The vast majority of these point-like X-ray-emitting sources at PN cores display relatively ''hard'' (≥0.5 keV) X-ray emission components that are unlikely to be due to photospheric emission from the hot central stars (CSPN). Instead, we demonstrate that these sources are well modeled by optically thin thermal plasmas. From the plasma properties, we identify two classes of CSPN X-ray emission: (1) high-temperature plasmas with X-ray luminosities, L {sub X}, that appear uncorrelated with the CSPN bolometric luminosity, L {sub bol} and (2) lower-temperature plasmas with L {sub X}/L {sub bol} ∼ 10{sup –7}. We suggest these two classes correspond to the physical processes of magnetically active binary companions and self-shocking stellar winds, respectively. In many cases this conclusion is supported by corroborative multiwavelength evidence for the wind and binary properties of the PN central stars. By thus honing in on the origins of X-ray emission from PN central stars, we enhance the ability of CSPN X-ray sources to constrain models of PN shaping that invoke wind interactions and binarity.

  4. The Chandra Planetary Nebula Survey (ChanPlaNS). III. X-Ray Emission from the Central Stars of Planetary Nebulae

    NASA Astrophysics Data System (ADS)

    Montez, R., Jr.; Kastner, J. H.; Balick, B.; Behar, E.; Blackman, E.; Bujarrabal, V.; Chu, Y.-H.; Corradi, R. L. M.; De Marco, O.; Frank, A.; Freeman, M.; Frew, D. J.; Guerrero, M. A.; Jones, D.; Lopez, J. A.; Miszalski, B.; Nordhaus, J.; Parker, Q. A.; Sahai, R.; Sandin, C.; Schonberner, D.; Soker, N.; Sokoloski, J. L.; Steffen, M.; Toalá, J. A.; Ueta, T.; Villaver, E.; Zijlstra, A.

    2015-02-01

    We present X-ray spectral analysis of 20 point-like X-ray sources detected in Chandra Planetary Nebula Survey observations of 59 planetary nebulae (PNe) in the solar neighborhood. Most of these 20 detections are associated with luminous central stars within relatively young, compact nebulae. The vast majority of these point-like X-ray-emitting sources at PN cores display relatively "hard" (>=0.5 keV) X-ray emission components that are unlikely to be due to photospheric emission from the hot central stars (CSPN). Instead, we demonstrate that these sources are well modeled by optically thin thermal plasmas. From the plasma properties, we identify two classes of CSPN X-ray emission: (1) high-temperature plasmas with X-ray luminosities, L X, that appear uncorrelated with the CSPN bolometric luminosity, L bol and (2) lower-temperature plasmas with L X/L bol ~ 10-7. We suggest these two classes correspond to the physical processes of magnetically active binary companions and self-shocking stellar winds, respectively. In many cases this conclusion is supported by corroborative multiwavelength evidence for the wind and binary properties of the PN central stars. By thus honing in on the origins of X-ray emission from PN central stars, we enhance the ability of CSPN X-ray sources to constrain models of PN shaping that invoke wind interactions and binarity.

  5. Soft x-ray shock loading and momentum coupling in meteorite and planetary materials.

    SciTech Connect

    Lawrence, R. Jeffery; Remo, John L.; Furnish, Michael David

    2010-12-01

    X-ray momentum coupling coefficients, C{sub M}, were determined by measuring stress waveforms in planetary materials subjected to impulsive radiation loading from the Sandia National Laboratories Z-machine. Results from the velocity interferometry (VISAR) diagnostic provided limited equation-of-state data as well. Targets were iron and stone meteorites, magnesium rich olivine (dunite) solid and powder ({approx}5--300 {mu}m), and Si, Al, and Fe calibration targets. All samples were {approx}1 mm thick and, except for Si, backed by LiF single-crystal windows. The x-ray spectrum included a combination of thermal radiation (blackbody 170--237 eV) and line emissions from the pinch material (Cu, Ni, Al, or stainless steel). Target fluences 0.4--1.7 kJ/cm{sup 2} at intensities 43--260 GW/cm{sup 2} produced front surface plasma pressures 2.6--12.4 GPa. Stress waves driven into the samples were attenuating due to the short ({approx}5 ns) duration of the drive pulse. Attenuating wave impulse is constant allowing accurate C{sub M} measurements provided mechanical impedance mismatch between samples and the window are known. Impedance-corrected C{sub M} determined from rear-surface motion was 1.9--3.1 x 10{sup -5} s/m for stony meteorites, 2.7 and 0.5 x 10{sup -5} s/m for solid and powdered dunite, 0.8--1.4 x 10{sup -5}.

  6. Planetary X ray experiment: Supporting research for outer planets mission: Experiment definition phase

    NASA Technical Reports Server (NTRS)

    Hurley, K.; Anderson, K. A.

    1972-01-01

    Models of Jupiter's magnetosphere were examined to predict the X-ray flux that would be emitted in auroral or radiation zone processes. Various types of X-ray detection were investigated for energy resolution, efficiency, reliability, and background. From the model fluxes it was determined under what models Jovian X-rays could be detected.

  7. The Role of X-Rays in Future Space Navigation and Communication

    NASA Technical Reports Server (NTRS)

    Winternitz, Luke M. B.; Gendreau, Keith C.; Hasouneh, Monther A.; Mitchell, Jason W.; Fong, Wai H.; Lee, Wing-Tsz; Gavriil, Fotis; Arzoumanian, Zaven

    2013-01-01

    In the near future, applications using X-rays will enable autonomous navigation and time distribution throughout the solar system, high capacity and low-power space data links, highly accurate attitude sensing, and extremely high-precision formation flying capabilities. Each of these applications alone has the potential to revolutionize mission capabilities, particularly beyond Earth orbit. This paper will outline the NASA Goddard Space Flight Center vision and efforts toward realizing the full potential of X-ray navigation and communications.

  8. Development of Standard Samples for on-board Calibration of a New Planetary X-Ray Fluorescence Spectrometer

    NASA Astrophysics Data System (ADS)

    Dreißigacker, Anne; Köhler, Eberhard; Fabel, Oliver; van Gasselt, Stephan

    2014-05-01

    At the Planetary Sciences and Remote Sensing research group at Freie Universität Berlin an SCD-based X-Ray Fluorescence Spectrometer is being developed to be employed on planetary orbiters to conduct direct, passive energy-dispersive x-ray fluorescence measurements of planetary surfaces through measuring the emitted X-Ray fluorescence induced by solar x-rays and high energy particles. Because the Sun is a highly variable radiation source, the intensity of solar X-Ray radiation has to be monitored constantly to allow for comparison and signal calibration of X-Ray radiation from lunar surface materials. Measurements are obtained by indirectly monitoring incident solar x-rays emitted from a calibration sample. This has the additional advantage of minimizing the risk of detector overload and damage during extreme solar events such as high-energy solar flares and particle storms as only the sample targets receive the higher radiation load directly (while the monitor is never directly pointing towards the Sun). Quantitative data are being obtained and can be subsequently analysed through synchronous measurement of fluorescence of the Moon's surface by the XRF-S main instrument and the emitted x-ray fluorescence of calibration samples by the XRF-S-ISM (Indirect Solar Monitor). We are currently developing requirements for 3 sample tiles for onboard correction and calibration of XRF-S, each with an area of 3-9 cm2 and a maximum weight of 45 g. This includes development of design concepts, determination of techniques for sample manufacturing, manufacturing and testing of prototypes and statistical analysis of measurement characteristics and quantification of error sources for the advanced prototypes and final samples. Apart from using natural rock samples as calibration sample, we are currently investigating techniques for sample manufacturing including laser sintering of rock-glass on metals, SiO2-stabilized mineral-powders, or artificial volcanic glass. High precision

  9. The challenge of developing thin mirror shells for future x-ray telescopes

    NASA Astrophysics Data System (ADS)

    Döhring, Thorsten; Stollenwerk, Manfred; Gong, Qingqing; Proserpio, Laura; Winter, Anita; Friedrich, Peter

    2015-09-01

    Previously used mirror technologies are not able to fulfil the requirements of future X-ray telescopes due to challenging requests from the scientific community. Consequently new technical approaches for X-ray mirror production are under development. In Europe the technical baseline for the planned X-ray observatory ATHENA is the radical new approach of silicon pore optics. NASÁs recently launched NuSTAR mission uses segmented mirrors shells made from thin bended glasses, successfully demonstrating the feasibility of the glass forming technology for X-ray mirrors. For risk mitigation also in Europe the hot slumping of thin glasses is being developed as an alternative technology for lightweight X-ray telescopes. The high precision mirror manufacturing requires challenging technical developments; several design trades and trend-setting decisions need to be made and are discussed within this paper. Some new technical and economic aspects of the intended glass mirror serial production are also studied within the recently started interdisciplinary project INTRAAST, an acronym for "industry transfer of astronomical mirror technologies". The goal of the project, embedded in a cooperation of the Max-Planck-Institute for extraterrestrial Physics and the University of Applied Sciences Aschaffenburg, is to master the challenge of producing thin mirror shells for future X-ray telescopes. As a first project task the development of low stress coatings for thin glass mirror substrates have been started, the corresponding technical approach and first results are presented.

  10. Prospects for X-ray absorption with the super-bright light sources of the future.

    PubMed

    Norman, D

    2001-03-01

    The immense growth in applications of X-ray absorption spectroscopy (XAS) has been enabled by the widespread availability of intense tunable X-rays from synchrotron radiation sources. Recently, new concepts have been proposed for fourth-generation light sources, such as the SASE (self-amplified stimulated emission) X-ray free-electron lasers (XFELs) being pursued at Hamburg (TESLA) and Stanford (LCLS), and the recirculator ring (MARS) at Novosibirsk. These sources offer expected gains of many orders of magnitude in instantaneous brilliance, which will unlock opportunities for qualitatively different science. Examples of new or greatly expanded techniques in XAS could include Raman X-ray absorption fine structure (XAFS), pump-probe experiments, time-resolved XAFS and small-spot X-ray spectromicroscopy, although the limited tunability of the sources might not allow conventional XAFS measurements. Multi-photon X-ray absorption could become a new field of study. There should not be a collective stampede to these new sources, however, and it is likely that storage rings will continue to be necessary for most XAFS applications. The extreme brightness of these future light sources will present difficult challenges in instrumentation, especially detectors and sample containment. Practitioners will also have to exercise caution, because the intensity of the beam will surely destroy many samples and in some cases there will be so many photons absorbed per atom that XAFS will be impossible.

  11. Automated X-ray image analysis for cargo security: Critical review and future promise.

    PubMed

    Rogers, Thomas W; Jaccard, Nicolas; Morton, Edward J; Griffin, Lewis D

    2017-01-01

    We review the relatively immature field of automated image analysis for X-ray cargo imagery. There is increasing demand for automated analysis methods that can assist in the inspection and selection of containers, due to the ever-growing volumes of traded cargo and the increasing concerns that customs- and security-related threats are being smuggled across borders by organised crime and terrorist networks. We split the field into the classical pipeline of image preprocessing and image understanding. Preprocessing includes: image manipulation; quality improvement; Threat Image Projection (TIP); and material discrimination and segmentation. Image understanding includes: Automated Threat Detection (ATD); and Automated Contents Verification (ACV). We identify several gaps in the literature that need to be addressed and propose ideas for future research. Where the current literature is sparse we borrow from the single-view, multi-view, and CT X-ray baggage domains, which have some characteristics in common with X-ray cargo.

  12. Future Probes of the Neutron Star Equation of State Using X-ray Bursts

    NASA Technical Reports Server (NTRS)

    Strohmayer, Tod E.

    2004-01-01

    Observations with NASA s Rossi X-ray Timing Explorer (RXTE) have resulted in the discovery of fast (200 - 600 Hz), coherent X-ray intensity oscillations (hereafter, %urstoscillations ) during thermonuclear X-ray bursts from 12 low mass X-ray binaries (LMXBs). Although many of their detailed properties remain to be fully understood, it is now beyond doubt that these oscillations result from spin modulation of the thermonuclear burst flux from the neutron star surface. Among the new timing phenomena revealed by RXTE the burst oscillations are perhaps the best understood, in the sense that many of their properties can be explained in the framework of this relatively simple model. Because of this, detailed modelling of burst oscillations can be an extremely powerful probe of neutron star structure, and thus the equation of state (EOS) of supra-nuclear density matter. Both the compactness parameter beta = GM/c(sup 2)R, and the surface velocity, nu(sub rot) = Omega(sub spin)R, are encoded in the energy-dependent amplitude and shape of the modulation pulses. The new discoveries have spurred much new theoretical work on thermonuclear burning and propagation on neutron stars, so that in the near future it is not unreasonable to think that detailed physical models of the time dependent flux from burning neutron stars will be available for comparison with the observed pulse profiles from a future, large collecting area X-ray timing observatory. In addition, recent high resolution burst spectroscopy with XMM/Newton suggests the presence of redshifted absorption lines from the neutron star surface during bursts. This leads to the possibility of using large area, high spectral resolution measurements of X-ray bursts as a precise probe of neutron star structure. In this work I will explore the precision with which constraints on neutron star structure, and hence the dense matter EOS, can be made with the implementation of such programs.

  13. High-energy density experiments on planetary materials using high-power lasers and X-ray free electron laser

    NASA Astrophysics Data System (ADS)

    Ozaki, Norimasa

    2015-06-01

    Laser-driven dynamic compression allows us to investigate the behavior of planetary and exoplanetary materials at extreme conditions. Our high-energy density (HED) experiments for applications to planetary sciences began over five years ago. We measured the equation-of-state of cryogenic liquid hydrogen under laser-shock compression up to 55 GPa. Since then, various materials constituting the icy giant planets and the Earth-like planets have been studied using laser-driven dynamic compression techniques. Pressure-volume-temperature EOS data and optical property data of water and molecular mixtures were obtained at the planetary/exoplanetary interior conditions. Silicates and oxides data show interesting behaviors in the warm-dense matter regime due to their phase transformations. Most recently the structural changes of iron were observed for understanding the kinetics under the bcc-hcp transformation phenomena on a new HED science platform coupling power-lasers and the X-ray free electron laser (SACLA). This work was performed under the joint research project at the Institute of Laser Engineering, Osaka University. It was partially supported by a Grant-in-Aid for Scientific Research (Grant Nos. 20654042, 22224012, 23540556, and 24103507) and also by grants from the Core-to-Core Program of JSPS on International Alliance for Material Science in Extreme States with High Power Laser and XFEL, and the X-ray Free Electron Laser Priority Strategy Program of MEXT.

  14. Future lunar mission Active X-ray Spectrometer development: Surface roughness and geometry studies

    NASA Astrophysics Data System (ADS)

    Naito, M.; Hasebe, N.; Kusano, H.; Nagaoka, H.; Kuwako, M.; Oyama, Y.; Shibamura, E.; Amano, Y.; Ohta, T.; Kim, K. J.; Lopes, J. A. M.

    2015-07-01

    The Active X-ray Spectrometer (AXS) is considered as one of the scientific payload candidates for a future Japanese mission, SELENE-2. The AXS consists of pyroelectric X-ray generators and a Silicon Drift Detector to conduct X-Ray Fluorescence spectroscopy (XRF) on the Moon to measure major elements: Mg, Al, Si, Ca, Ti, and Fe; minor elements: Na, K, P, S, Cr and Mn; and the trace element Ni depending on their concentration. Some factors such as roughness, grain size and porosity of sample, and the geometry of X-ray incidence, emission and energy will affect the XRF measurements precision. Basic studies on the XRF are required to develop the AXS. In this study, fused samples were used to make homogeneous samples free from the effect of grain size and porosity. Experimental and numerical studies on the XRF were conducted to evaluate the effects from incidence and emission angles and surface roughness. Angle geometry and surface roughness will be optimized for the design of the AXS on future missions from the results of the experiment and the numerical simulation.

  15. Fabrication and testing of off-plane gratings for future x-ray spectroscopy missions

    NASA Astrophysics Data System (ADS)

    DeRoo, Casey T.

    Soft X-ray spectroscopy is a useful observational tool, offering information about high-temperature (106 - 107 K) astrophysical plasmas and providing useful characterizations of a number of energetic systems, including accreting young stars, cosmic filaments between galaxies, and supermassive black holes. In order to yield high resolution spectra with good signal-to-noise, however, soft X-ray spectrometers must realize improvements in resolving power and effective area through the development of high performance gratings. Off-plane reflection gratings offer the capability to work at high dispersions with excellent throughput, and are a viable candidate technology for future X-ray spectroscopy missions. The off-plane geometry requires a customizable grating meeting distinct fabrication requirements, and a process for producing gratings meeting these requirements has been developed. These fabricated gratings have been evaluated for performance in terms of resolution and diffraction efficiency. Furthermore, these gratings have been conceptually implemented in a soft X-ray spectrometer, the Off-Plane Grating Rocket Experiment (OGRE), whose optical design provides a template for future missions to achieve high performance within a small payload envelope.

  16. Measuring optical constants of multilayer materials for current and future hard X-ray space telescopes

    NASA Astrophysics Data System (ADS)

    Brejnholt, Nicolai

    extensive experience on the topic of X-ray optical constants and related methodologies and have laid out a carefully designed campaign to determine the optical constants. In addition to providing a significant contribution to an on-going NASA mission, the proposed work will also directly benefit the Japanese (JAXA) ASTRO-H mission and the future European (ESA) mission Athena.

  17. NASA's Future X-ray Missions: From Constellation-X to Generation-X

    NASA Technical Reports Server (NTRS)

    Hornschemeier, A.

    2006-01-01

    Among the most important topics in modern astrophysics are the formation and evolution of supermassive black holes in concert with galaxy bulges, the nature of the dark energy equation of state, and the self-regulating symmetry imposed by both stellar and AGN feedback. All of these topics are readily addressed with observations at X-ray wavelengths. NASA's next major X-ray observatory is Constellation-X, which is being developed to perform spatially resolved high-resolution X-ray spectroscopy. Con-X will directly measure the physical properties of material near black holes' last stable orbits and the absolute element abundances and velocities of hot gas in clusters of galaxies. The Con-X mission will be described, as well as its successor, Generation-X (anticipated to fly approx.1 decade after Con-X). After describing these missions and their driving science areas, the talk will focus on areas in which Chandra observing programs may enable science with future X-ray observatories. These areas include a possible ultra-deep Chandra imaging survey as an early Universe pathfinder, a large program to spatially resolve the hot intracluster medium of massive clusters to aid dark energy measurements, and possible deep spectroscopic observations to aid in preparatory theoretical atomic physics work needed for interpreting Con-X spectra.

  18. Future Japanese X-ray TES Calorimeter Satellite: DIOS (Diffuse Intergalactic Oxygen Surveyor)

    NASA Astrophysics Data System (ADS)

    Yamada, S.; Ohashi, T.; Ishisaki, Y.; Ezoe, Y.; Miyazaki, N.; Kuwabara, K.; Kuromaru, G.; Suzuki, S.; Mitsuda, K.; Yamasaki, N. Y.; Takei, Y.; Sakai, K.; Nagayoshi, K.; Yamamoto, R.; Hayashi, T.; Muramatsu, H.; Tawara, Y.; Mitsuishi, I.; Babazaki, Y.; Nakamichi, R.; Bandai, A.; Yuasa, T.; Ota, N.

    2016-08-01

    We present the latest update and progress on the future Japanese X-ray satellite mission Diffuse Intergalactic Oxygen Surveyor (DIOS). DIOS is proposed to JAXA as a small satellite mission, and would be launched with an Epsilon rocket. DIOS would carry on the legacy of ASTRO-H, which carries semiconductor-based microcalorimeters and is scheduled to be launched in 2016, in high-resolution X-ray spectroscopy. A 400-pixel array of transition-edge sensors (TESs) would be employed, so DIOS would also provide valuable lessons for the next ESA X-ray mission ATHENA on TES operation and cryogen-free cooling in space. We have been sophisticating the entire design of the satellite to meet the requirement for the Epsilon payload for the next call. The primary goal of the mission is to search for warm-hot intergalactic medium with high-resolution X-ray spectroscopy by detecting redshifted emission lines from OVII and OVIII ions. The results would have significant impacts on our understanding of the nature of "dark baryons," their total amount and spatial distribution, as well as their evolution over cosmological timescales.

  19. Dynamical Studies Using Coherent X-rays: A Short Review and Prospects for the Future

    SciTech Connect

    Sinha, Sunil K.

    2010-07-07

    The use of coherent x-ray beams for studying the structure and dynamics of both surfaces and bulk materials is rapidly increasing due to the advent of new high-brilliance x-ray sources. The field of x-ray photon correlation spectroscopy (XPCS) has steadily grown from demonstration experiments carried out some 15 years ago, to studies addressing real problems at the forefront of condensed matter and has attracted increasing numbers of users. the principal applications have been in the fields of soft condensed matter and nanoscience, but extension to the study of slow fluctuations in magnetic systems will undoubtedly grow. This talk will attempt to survey some of the recent applications at the limits of currently existing instruments, and present a wish list for XPCS-capable beamlines of the future for attacking certain important problems in condensed matter and materials science. This talk will also present a new formulation of the scattering of partially coherent radiation by condensed matter, which will enable us to go beyond the simple, kinematic approximation that is usually made, but which breaks down for grazing incidence small-angle x-ray scattering geometry.

  20. Plasma-driven Z-pinch X-ray loading and momentum coupling in meteorite and planetary materials

    NASA Astrophysics Data System (ADS)

    Remo, John L.; Furnish, Michael D.; Lawrence, R. Jeffery; Lawrence

    2013-04-01

    X-ray momentum coupling coefficients, C M, were determined by measuring stress waveforms in planetary materials subjected to impulsive radiation loading from the Sandia National Laboratories Z-machine. Velocity interferometry (VISAR) diagnostics provided equation-of-state data. Targets were iron and stone meteorites, magnesium-rich olivine (dunite) solid and powder (~5-300 μm), and Si, Al, and Fe calibration targets. Samples were ~1-mm thick and, except for Si, backed by LiF single-crystal windows. X-ray spectra combined thermal radiation (blackbody 170-237 eV) and line emissions from pinch materials (Cu, Ni, Al, or stainless steel). Target fluences of 0.4-1.7 kJ/cm2 at intensities of 43-260GW/cm2 produced plasma pressures of 2.6-12.4 GPa. The short (~5 ns) drive pulses gave rise to attenuating stress waves in the samples. The attenuating wave impulse is constant, allowing accurate C M measurements from rear-surface motion. C M was 1.9 - 3.1 × 10-5 s/m for stony meteorites, 2.7 and 0.5 × 10-5 s/m for solid and powdered dunite, 0.8 - 1.4 × 10-5 s/m for iron meteorites, and 0.3, 1.8, and 2.7 × 10-5 s/m respectively for Si, Fe, and Al calibration targets. Results are consistent with geometric scaling from recent laser hohlraum measurements. CTH hydrocode modeling of X-ray coupling to porous silica corroborated experimental measurements and supported extrapolations to other materials. CTH-modeled C M for porous materials was low and consistent with experimental results. Analytic modeling (BBAY) of X-ray radiation-induced momentum coupling to selected materials was also performed, often producing higher C M values than experimental results. Reasons for the higher values include neglect of solid ejecta mechanisms, turbulent mixing of heterogeneous phases, variances in heats of melt/vaporization, sample inhomogeneities, wave interactions at the sample/window boundary, and finite sample/window sizes. The measurements validate application of C M to (inhomogeneous

  1. Development of an X-ray surface analyzer for planetary exploration

    NASA Technical Reports Server (NTRS)

    Clark, B. C.

    1972-01-01

    An ultraminiature X-ray fluorescence spectrometer was developed which can obtain data on element composition not provided by present spacecraft instrumentation. The apparatus employs two radioisotope sources (Fe-55 and Cd-109) which irradiate adjacent areas on a soil sample. Fluorescent X-rays emitted by the sample are detected by four thin-window proportional counters. Using pulse-height discrimination, the energy spectra are determined. Virtually all elements above sodium in the periodic table are detected if present at sufficient levels. Minimum detection limits range from 30 ppm to several percent, depending upon the element and the matrix. For most elements, they are below 0.5 percent. Accuracies likewise depend upon the matrix, but are generally better than plus or minus 0.5 percent for all elements of atomic number greater than 14. Elements below sodium are also detected, but as a single group.

  2. Light-weight glass mirror systems for future x-ray telescopes

    NASA Astrophysics Data System (ADS)

    Winter, Anita; Breunig, Elias; Burwitz, Vadim; Friedrich, Peter; Hartner, Gisela; Menz, Benedikt; Proserpio, Laura

    2013-09-01

    Future X-ray telescopes need to combine large collecting area with good angular resolution. In order to achieve these aims within the mass limit, light-weight materials are needed for mirror production. We are developing a technology based on indirect hot slumping of thin glass segments; this method enables the production of the parabolic and hyperbolic part of the Wolter type I mirrors in one piece. Currently we use a combination of a porous ceramic for the slumping mould and the glass type D263 for the mirror material. In this study we use glasses that have been polished on one side to remove thickness variations in the glass, in order to investigate their influence on the results. We describe the experimental set-up, the slumping process and the metrology methods. Finally we present the results of an X-ray test of several integrated glass sheets, and give an outlook on future activities.

  3. Future Development Trajectories for Imaging X-rays Spectrometers Based on Microcalorimeters

    NASA Technical Reports Server (NTRS)

    Kilbourne, Caroline A.; Bandler, Simon R.

    2013-01-01

    Future development trajectories for imaging x-ray spectrometers based on microcalorimeters. Since their invention 30 years ago, the capability of X-ray microcalorimeters has increased steadily, with continual improvements in energy resolution, speed, and array size. Arrays of up to 1024 pixels have been produced, and resolution better than 1 eV at 1.5 keV has been achieved. These detectors can be optimized for the highest priority science, such as designing for the highest resolving power at low energies at the expense of dynamic range, or the greatest focal-plane coverage at the expense of speed. Three types of X-ray microcalorimeters presently dominate the field, each characterized by the thermometer technology. The first two types use temperature-sensitive resistors: semiconductors in the metal-insulator transition and superconductors operated in the superconducting-normal transition. The third type uses a magnetically coupled thermometer, and is at an earlier stage of development than the other two. The Soft X-ray Spectrometer (SXS) on Astro-H, expected to launch in 2015, will use an array of silicon thermistors with HgTe X-ray absorbers that will operate at 50 mK. Both the semiconductor and superconductor calorimeters have been implemented in small arrays. Kilopixel arrays of the superconducting calorimeters are being produced, and much larger arrays may require the non-dissipative advantage of magnetically coupled thermometers. I will project the development trajectories of these detectors and their read-out technologies and assess what their capabilities and limitations will be 10 - 20 years from now.

  4. Micro-Scanning Electron Microscope and X-ray Spectrometer for Planetary Exploration

    NASA Astrophysics Data System (ADS)

    Blake, D. F.; Nguyen, C. V.; Dholakia, G.; Ribaya, B. P.; Niemann, D.; Ngo, V.; McKenzie, C.; Rahman, M.; Alam, A.; Joy, D.; Espinosa, B.

    2007-12-01

    Scanning Electron Microscopy combined with electron-induced X-ray Fluorescence Spectroscopy (SEM-EDX) is one of the most powerful techniques for characterizing surface morphology and composition with spatial resolution of a micrometer or better. SEM-EDX can elucidate natural processes such as low-temperature diagenesis, thermal or pressure induced metamorphism, volcanism/magmatism, atmosphere/crust interaction and the like. This information is useful for the investigation of the natural history of solar system objects. We are developing a prototype micromachined scanning electron microscope with X-ray spectrometer (MSEMS) for solar system exploration. The MSEMS is comprised of a carbon nanotube field emission (CNTFE) electron source integrated with a micro-electro-mechanical-system (MEMS) based electron gun and electron optics structure. The MSEMS system will utilize a piezoelectric sample stage, having scan ranges from a few angstroms to several hundreds of microns. Compared with conventional electron sources, the CNTFE source offers advantages of low power usage, ultra-small source size and simplicity of electrostatic focusing. The MSEMS instrument, including CNTFE source, MEMS electron optic column and piezoelectric sample stage, is envisioned to be 1-2 cm in height and will operate in the range of 500 eV to 15 KeV. The imaging resolution of MEMS is predicted to be ~10 nm at 5 KeV and the spatial resolution of the X-ray spectrometer will be ~1 μm at 15 KeV. We will present field emission data from our CNTFE source as well as the MEMS electron gun and piezostage designs.

  5. Past, Present and Future Prospects of High Resolution X-ray Spectroscopy of Clusters of Galaxies

    NASA Astrophysics Data System (ADS)

    Kaastra, J.

    2006-08-01

    The first high resolution X-ray spectra of clusters of galaxies have revolutionised the study of cooling flows. These excellent data have been obtained with an instrument (the RGS of XMM-Newton) that has not been optimised for spectroscopy of extended sources. I will present a few recent examples of what can be achieved further with the RGS in combination with the imaging EPIC cameras for the study of chemical enrichment of clusters. The new generation of high spectral resolution imaging TES arrays that is currently being studied for a variety of possible future X-ray observatories (such as XEUS, Constellation-X, DIOS, Estremo and NEW) offer exciting new opportunities to study the physics of clusters of galaxies. I will present examples of how these new instruments will achieve this.

  6. Athena and future plans of the X-ray astronomy in Japan

    NASA Astrophysics Data System (ADS)

    Matsumoto, Hiro

    2015-09-01

    High-Energy AstroPhysics Association in Japan (HEAPA) officially decided to contribute to the success of Athena based on our expertise through the development of ASTRO-H, Suzaku, and other satellites. The Athena Working Group (WG) of ISAS/JAXA was set up and the WG applied to the call for the MoO mission of ISAS/JAXA. In this talk, we would like to explain the Japanese contribution to the Athena satellite. Also we would like to talk about the future plan of Japanese X-ray astronomy missions. For example, Diffuse Intergalactic Oxygen Surveyor (DIOS) and Next-Generation Hard X-ray Telescope (NGHXT) will be introduced, and the relation between the Athena project and those missions will be given.

  7. An alpha particle instrument with alpha, proton, and X-ray modes for planetary chemical analyses

    NASA Technical Reports Server (NTRS)

    Economou, T. E.; Turkevich, A. L.

    1976-01-01

    The interaction of alpha particles with matter is employed in a compact instrument that could provide rather complete in-situ chemical analyses of surfaces and thin atmospheres of extraterrestrial bodies. The instrument is a miniaturized and improved version of the Surveyor lunar instrument. The backscattering of alpha particles and (alpha, p) reactions provide analytical data on the light elements (carbon-iron). An X-ray mode that detects the photons produced by the alpha sources provides sensitivity and resolution for the chemical elements heavier than about silicon. The X-rays are detected by semiconductor detectors having a resolution between 150 and 250 eV at 5.9 keV. Such an instrument can identify and determine with good accuracy 99 percent of the atoms (except hydrogen) in rocks. For many trace elements, the detecting sensitivity is a few ppm. Auxiliary sources could be used to enhance the sensitivities for elements of special interest. The instrument could probably withstand the acceleration involved in semi-hard landings.

  8. An alpha particle instrument with alpha, proton, and X-ray modes for planetary chemical analyses

    NASA Technical Reports Server (NTRS)

    Economou, T. E.; Turkevich, A. L.

    1976-01-01

    The interaction of alpha particles with matter is employed in a compact instrument that could provide rather complete in-situ chemical analyses of surfaces and thin atmospheres of extraterrestrial bodies. The instrument is a miniaturized and improved version of the Surveyor lunar instrument. The backscattering of alpha particles and (alpha, p) reactions provide analytical data on the light elements (carbon-iron). An X-ray mode that detects the photons produced by the alpha sources provides sensitivity and resolution for the chemical elements heavier than about silicon. The X-rays are detected by semiconductor detectors having a resolution between 150 and 250 eV at 5.9 keV. Such an instrument can identify and determine with good accuracy 99 percent of the atoms (except hydrogen) in rocks. For many trace elements, the detecting sensitivity is a few ppm. Auxiliary sources could be used to enhance the sensitivities for elements of special interest. The instrument could probably withstand the acceleration involved in semi-hard landings.

  9. Early History and Future Outlook for the X-ray Crystal Density Method

    NASA Astrophysics Data System (ADS)

    Deslattes, R. D.

    1994-01-01

    It is useful to recall that the (late nineteenth-century) Baltimore Lectures of Lord Kelvin indicated that the likely sizes of atomic particles spanned almost two decades. Yet in the early years of the present century, Sir William Bragg's ansatz, together with the oil-drop e, gave the first reliable estimate of the scale of crystal interplanar spacings. The converse process of using an XRCD approach to obtain a value for the Avogadro constant was, prior to the advent of x-ray interferometry, limited by the need to connect optical and x-ray wavelengths before using the latter to estimate unit cell dimensions in crystals. Other limitations of these early measurements included the use of water as a density standard and the assignment of molar masses to individual specimens based on geochemical abundance averages. All these difficulties were overcome, in principle, with the application of x-ray/optical interferometry to the determination of lattice periods, the use of solid object density standards, and the determination of densities and isotopic abundances on individual monocrystalline specimens. While the present-day situation is addressed in other contributions to this workshop, the present essay attempts to place some of the early work in context and to look also to the future.

  10. Performance of a Borehole X-ray Fluorescence Spectrometer for Planetary Exploration

    NASA Technical Reports Server (NTRS)

    Kelliher, Warren C.; Carlberg, Ingrid A.; Elam, W. T.; Willard-Schmoe, Ella

    2008-01-01

    We have designed and constructed a borehole X-ray Fluorescence Spectrometer (XRFS) as part of the Mars Subsurface Access program [1]. It can be used to determine the composition of the Mars regolith at various depths by insertion into a pre-drilled borehole. The primary requirements and performance metrics for the instrument are to obtain parts-per-million (ppm) lower limits of detection over a wide range of elements in the periodic table (Magnesium to Lead). Power consumption during data collection was also measured. The prototype instrument is complete and preliminary testing has been performed. Terrestrial soil Standard Reference Materials were used as the test samples. Detection limits were about 10 weight ppm for most elements, with light elements being higher, up to 1.4 weight percent for magnesium. Power consumption (excluding ground support components) was 12 watts.

  11. Combined Backscatter Moessbauer Spectrometer and X Ray Fluorescence analyzer (BaMS/XRF) for planetary surface materials

    NASA Technical Reports Server (NTRS)

    Agresti, D. G.; Shelfer, T. D.; Pimperl, M. M.; Wills, E. L.; Morris, R. V.

    1991-01-01

    A backscatter Moessbauer spectrometer (BaMS) with included x ray fluorescence (XRF) capability for the Mars Environment Survey (MESUR) Mission, which has been proposed by NASA for 1998, is being developed. The instrument will also be suitable for other planetary missions such as those to the Moon, asteroids, and other solid solar-system objects. The BaMS would be unique for MESUR in providing information about iron mineralogy in rocks, clays, and other surface materials, including relative proportions of iron-bearing minerals. It requires no sample preparation and can identify all the normal oxidation states of iron (3+, 2+, 0). Thus, BaMS is diagnostic for weathering and other soil-forming processes. Backscatter design allows the addition of XRF elemental analysis with little or no modification. The BaMS/XRF instrument complements the thermal analyzer with evolved gas analyzer (TA-EGA) and the alpha-proton x-ray spectrometer (APXS) proposed (along with BaMS) for geochemical analysis on MESUR.

  12. Black holes, formation of structure, and extreme physics: the present and future of X-ray astrophysics

    NASA Astrophysics Data System (ADS)

    Kraft, Ralph; Bautz, Mark

    2017-01-01

    X-ray astrophysics lies at the conjunction of many of the big picture questions we have about our Universe. We detect X-rays from supermassive black holes when the Universe was 7% of its present age, just after the formation of the first galaxies. Most of the baryons in the Universe are in clusters or in the filaments between collapsed structures heated to X-ray emitting temperatures. X-ray studies of the evolution of these collapsed structures provide strong constraints on cosmological parameters. Studies by future X-ray observatories of this hot filamentary gas between clusters and of halos of galaxies will provide unique windows in the processes of the early universe and formation of structure. In this presentation, we discuss the current state of X-ray astrophysics. We will present the status of and recent science highlights from the current generation of X-ray observatories. We will outline the scientific potential for missions that will soon be launched including NICER, eRosita, and a potential refly of the Hitomi mission, as well as longer term missions such as the European L2 Athena mission. Finally, we will summarize the status of the X-ray Surveyor, one of the four large mission concepts under study prior to the 2020 Astrophysics Decadal Review.

  13. Micro-column Scanning Electron Microscope and X-ray Spectrometer (MSEMS) for Planetary Exploration

    NASA Astrophysics Data System (ADS)

    Ribaya, B.; Niemann, D.; Makarewicz, J.; Clevenson, H.; McKenzie, C.; Nguyen, C.; Blake, D. F.

    2009-12-01

    Scanning Electron Microscopy combined with electron-induced X-ray Fluorescence Spectroscopy (SEM-EDX) is one of the most powerful techniques for characterizing sub-µm surface morphology and composition. In terrestrial laboratories, SEM-EDX is used to elucidate natural processes such as low-temperature diagenesis, thermal or pressure induced metamorphism, volcanism/magmatism, atmosphere/crust interaction and biological activity. Such information would be highly useful for investigating the natural history of the terrestrial planets, satellites and primitive bodies, providing morphological and elemental information that is 2 orders of magnitude higher in resolution than optical techniques. Below we describe the development of a Micro-column Scanning Electron Microscope and X-ray Spectrometer (MSEMS) for flight. The enabling technology of the MSEMS is a carbon nanotube field emission (CNTFE) electron source that is integrated with micro-electro-mechanical-systems (MEMS) - based electron gun and electron optical structures. A hallmark of CNTFE electron sources is their low chromatic aberration, which reduces the need for high accelerating voltages to obtain small spot size. The CNTFE also offers exceptional brightness and nanometer source size, eliminating the need for condenser lenses, making simple electrostatic focusing optics possible. Moreover, the CNT field emission gun (CFEG) at low operating voltage dissipates 103 less power than thermally-assisted Schottky emitters. A key feature of the MSEMS design is the lack of scanning coils. Rather, a piezoelectric sample stage capable of sub-nanometer resolution scans the sample past the fixed crossover of the MSEMS electron beam. We will describe a MEMS-based templating technique for fabricating mechanically and electrically stable miniature CFEGs. Using existing silicon (Si) technology, we fabricated highly controlled and precise MEMS structures for both the CNT cathode and focusing optics for the micro-column. The

  14. Serendipitous Detection of X-Ray Emission from the Hot Born-again Central Star of the Planetary Nebula K 1-16

    NASA Astrophysics Data System (ADS)

    Montez, Rodolfo, Jr.; Kastner, Joel H.

    2013-03-01

    We report the serendipitous detection of point-like X-ray emission from the hot, PG1159-type central star of the planetary nebula (CSPN) K 1-16 by the XMM-Newton and Chandra X-Ray Observatories. The CSPN lies superimposed on a galaxy cluster that includes an X-ray-bright quasar, but we have successfully isolated the CSPN X-ray emission from the strong diffuse background contributed by the quasar and intracluster gas. We have modeled the XMM-Newton and Chandra X-ray data, taking advantage of the contrasting detection efficiencies of the two observatories to better constrain the low-energy spectral response of Chandra's Advanced CCD Imaging Spectrometer. We find that the CSPN X-ray spectrum is well characterized by the combination of a non-local thermodynamic equilibrium model atmosphere with T sstarf ~ 135 kK and a carbon-rich, optically thin thermal plasma with T X ~ 1 MK. These results for X-ray emission from the K 1-16 CSPN, combined with those obtained for other PG1159-type objects, lend support to the "born-again" scenario for Wolf-Rayet and PG1159 CSPNe, wherein a late helium shell flash dredges up carbon-rich intershell material and ejects this material into the circumstellar environment.

  15. SERENDIPITOUS DETECTION OF X-RAY EMISSION FROM THE HOT BORN-AGAIN CENTRAL STAR OF THE PLANETARY NEBULA K 1-16

    SciTech Connect

    Montez, Rodolfo Jr.; Kastner, Joel H. E-mail: jhk@cis.rit.edu

    2013-03-20

    We report the serendipitous detection of point-like X-ray emission from the hot, PG1159-type central star of the planetary nebula (CSPN) K 1-16 by the XMM-Newton and Chandra X-Ray Observatories. The CSPN lies superimposed on a galaxy cluster that includes an X-ray-bright quasar, but we have successfully isolated the CSPN X-ray emission from the strong diffuse background contributed by the quasar and intracluster gas. We have modeled the XMM-Newton and Chandra X-ray data, taking advantage of the contrasting detection efficiencies of the two observatories to better constrain the low-energy spectral response of Chandra's Advanced CCD Imaging Spectrometer. We find that the CSPN X-ray spectrum is well characterized by the combination of a non-local thermodynamic equilibrium model atmosphere with T{sub *} {approx} 135 kK and a carbon-rich, optically thin thermal plasma with T{sub X} {approx} 1 MK. These results for X-ray emission from the K 1-16 CSPN, combined with those obtained for other PG1159-type objects, lend support to the 'born-again' scenario for Wolf-Rayet and PG1159 CSPNe, wherein a late helium shell flash dredges up carbon-rich intershell material and ejects this material into the circumstellar environment.

  16. X-Ray Imaging of Planetary Nebulae with Wolf-Rayet-type Central Stars: Detection of the Hot Bubble in NGC 40

    NASA Astrophysics Data System (ADS)

    Montez, Rodolfo, Jr.; Kastner, Joel H.; De Marco, Orsola; Soker, Noam

    2005-12-01

    We present the results of Chandra X-Ray Observatory observations of the planetary nebulae (PNs) NGC 40 and Hen 2-99. Both PNs feature late-type Wolf-Rayet central stars that are currently driving fast (~1000 km s-1), massive winds into denser, slow-moving (~10 km s-1) material ejected during recently terminated asymptotic giant branch (AGB) evolutionary phases. Hence, these observations provide key tests of models of wind-wind interactions in PNs. In NGC 40, we detect faint, diffuse X-ray emission distributed within a partial annulus that lies nested within a ~40" diameter ring of nebulosity observed in optical and near-infrared images. Hen 2-99 is not detected. The inferred X-ray temperature (TX~106 K) and luminosity (LX~2×1030 ergs s-1) of NGC 40 are the lowest measured thus far for any PN displaying diffuse X-ray emission. These results, combined with the ringlike morphology of the X-ray emission from NGC 40, suggest that its X-ray emission arises from a ``hot bubble'' that is highly evolved and is generated by a shocked, quasi-spherical fast wind from the central star, as opposed to AGB or post-AGB jet activity. In contrast, the lack of detectable X-ray emission from Hen 2-99 suggests that this PN has yet to enter a phase of strong wind-wind shocks.

  17. Future planetary television cameras

    NASA Technical Reports Server (NTRS)

    Norris, D. D.; Landauer, F. P.

    1976-01-01

    The evolution of planetary slow-scan vidicon cameras started with the exploratory flyby mission to Mars in 1965, and has continued through the planned launch of the Mariner Jupiter/Saturn 1977 Mission. To date, the camera performance has been constrained by limited spacecraft capabilities rather than driven by desires of experimenters. The paper traces this evolution for a generation of camera using charge-coupled device (CCD) sensors, which have greater capability within spacecraft weight and power constraints. Projections are given of scientific objectives for the CCD cameras, and it is shown how these objectives will drive the camera performance, data rates, on-board processing, pointing accuracy, and other spacecraft system parameters.

  18. Development of a TES-Based Anti-Coincidence Detector for Future X-Ray Observations

    NASA Technical Reports Server (NTRS)

    Bailey, Catherine N.; Adams, J. S.; Bandler, S. R.; Eckart, M. E.; Ewin, A. J.; Finkbeiner, F. M.; Kelley, R. L.; Kilbourne, C. A.; Porter, F. S.; Sadleir, J. E.; hide

    2012-01-01

    Microcalorimeters onboard future x-ray observatories require an anticoincidence detector to remove environmental backgrounds. In order to most effectively integrate this anti-coincidence detector with the main microcalorimeter array, both instruments should use similar read-out technology. The detectors used in the Cryogenic Dark Matter Search (CDMS) use a phonon measurement technique that is well suited for an anti-coincidence detector with a microcalorimeter array using SQUID readout. This technique works by using a transition-edge sensor (TES) connected to superconducting collection fins to measure the athermal phonon signal produced when an event occurs in the substrate crystal. Energy from the event propagates through the crystal to the superconducting collection fins, creating quasiparticles, which are then trapped as they enter the TES where they produce a signal. We are currently developing a prototype anti-coincidence detector for future x-ray missions and have recently fabricated test devices with Mo/Au TESs and Al collection fins. We present results from the first tests of these devices which indicate a proof of concept that quasiparticle trapping is occurring in these materials.

  19. Development of a TES-Based Anti-Coincidence Detector for Future X-ray Observatories

    NASA Technical Reports Server (NTRS)

    Bailey, Catherine

    2011-01-01

    Microcalorimeters onboard future x-ray observatories require an anti-coincidence detector to remove environmental backgrounds. In order to most effectively integrate this anticoincidence detector with the main microcalorimeter array, both instruments should use similar read-out technology. The detectors used in the Cryogenic Dark Matter Search (CDMS) use a phonon measurement technique that is well suited for an anti-coincidence detector with a microcalorimeter array using SQUID readout. This technique works by using a transition-edge sensor (TES) connected to superconducting collection fins to measure the athermal phonon signal produced when an event occurs in the substrate crystal. Energy from the event propagates through the crystal to the superconducting collection fins, creating quasiparticles, which are then trapped as they enter the TES where they produce a signal. We are currently developing a prototype anti-coincidence detector for future x-ray missions and have recently fabricated test devices with Mo/Au TESs and Al collection fins. We will present results from the first tests of these devices which indicate a proof of concept that quasiparticle trapping is occurring in these materials.

  20. Development of a TES-Based Anti-Coincidence Detector for Future X-Ray Observations

    NASA Technical Reports Server (NTRS)

    Bailey, Catherine N.; Adams, J. S.; Bandler, S. R.; Eckart, M. E.; Ewin, A. J.; Finkbeiner, F. M.; Kelley, R. L.; Kilbourne, C. A.; Porter, F. S.; Sadleir, J. E.; Smith, S. J.; Sultana, M.

    2012-01-01

    Microcalorimeters onboard future x-ray observatories require an anticoincidence detector to remove environmental backgrounds. In order to most effectively integrate this anti-coincidence detector with the main microcalorimeter array, both instruments should use similar read-out technology. The detectors used in the Cryogenic Dark Matter Search (CDMS) use a phonon measurement technique that is well suited for an anti-coincidence detector with a microcalorimeter array using SQUID readout. This technique works by using a transition-edge sensor (TES) connected to superconducting collection fins to measure the athermal phonon signal produced when an event occurs in the substrate crystal. Energy from the event propagates through the crystal to the superconducting collection fins, creating quasiparticles, which are then trapped as they enter the TES where they produce a signal. We are currently developing a prototype anti-coincidence detector for future x-ray missions and have recently fabricated test devices with Mo/Au TESs and Al collection fins. We present results from the first tests of these devices which indicate a proof of concept that quasiparticle trapping is occurring in these materials.

  1. Monte-Carlo background simulations of present and future detectors in x-ray astronomy

    NASA Astrophysics Data System (ADS)

    Tenzer, C.; Kendziorra, E.; Santangelo, A.

    2008-07-01

    Reaching a low-level and well understood internal instrumental background is crucial for the scientific performance of an X-ray detector and, therefore, a main objective of the instrument designers. Monte-Carlo simulations of the physics processes and interactions taking place in a space-based X-ray detector as a result of its orbital environment can be applied to explain the measured background of existing missions. They are thus an excellent tool to predict and optimize the background of future observatories. Weak points of a design and the main sources of the background can be identified and methods to reduce them can be implemented and studied within the simulations. Using the Geant4 Monte-Carlo toolkit, we have created a simulation environment for space-based detectors and we present results of such background simulations for XMM-Newton's EPIC pn-CCD camera. The environment is also currently used to estimate and optimize the background of the future instruments Simbol-X and eRosita.

  2. The ultrafast high-peak power lasers in future biomedical and medical x-ray imaging

    NASA Astrophysics Data System (ADS)

    Kieffer, J. C.; Fourmaux, S.; Krol, A.

    2016-01-01

    This paper reviews recent progresses in ultrafast laser-based X-ray sources and their potential applications to high throughput X-ray imaging. Prospects for the utilization of X-rays sources related to the Laser Wakefield electron Acceleration (LWFA) are more specifically discussed with emphasis on application in diagnostic radiology.

  3. Current and Future X-ray Studies of High-Redshift AGNs and the First Supermassive Black Holes

    NASA Astrophysics Data System (ADS)

    Brandt, Niel

    2016-01-01

    X-ray observations of high-redshift AGNs at z = 4-7 have played a critical role in understanding the physical processes at work inthese objects as well as their basic demographics. Since 2000, Chandra and XMM-Newton have provided new X-ray detections for more than 120 such objects, and well-defined samples of z > 4 AGNs now allow reliable X-ray population studies. Once luminosity effectsare considered, the basic X-ray continuum properties of most high-redshift AGNs appear remarkably similar to those of local AGNs, although there are some notable apparent exceptions (e.g., highly radio-loud quasars). Furthermore, the X-ray absorption found in some objects has been used as a diagnostic of outflowing winds and circumnuclear material. Demographically, the X-ray data now support an exponential decline in the number density of luminous AGNs above z ~ 3, and quantitative space-density comparisons for optically selected and X-ray selected quasars indicate basic statistical agreement.The current X-ray discoveries point the way toward the future breakthroughs that will be possible with, e.g., Athena and the X-raySurveyor. These missions will execute powerful blank-field surveys to elucidate the demographics of the first growing supermassive black holes (SMBHs), including highly obscured systems, up to z ~ 10. They will also carry out complementary X-ray spectroscopic and variability investigations of high-redshift AGNs by targeting the most-luminous z = 7-10 quasars found in wide-field surveys by, e.g., Euclid, LSST, and WFIRST. X-ray spectroscopic and variability studies of the X-ray continuum and reflection signatures will help determine Eddington ratios and disk/corona properties; measuring these will clarify how the first quasars grew so quickly. Furthermore, absorption line/edge studies will reveal how outflows from the first SMBHs influenced the growth of the first galaxies. I will suggest some efficient observational strategies for Athena and the X-ray Surveyor.

  4. Development of mirrors made of chemically tempered glass foils for future X-ray telescopes

    NASA Astrophysics Data System (ADS)

    Salmaso, Bianca; Civitani, Marta; Brizzolari, Claudia; Basso, Stefano; Ghigo, Mauro; Pareschi, Giovanni; Spiga, Daniele; Proserpio, Laura; Suppiger, Yves

    2015-10-01

    Thin slumped glass foils are considered good candidates for the realization of future X-ray telescopes with large effective area and high spatial resolution. However, the hot slumping process affects the glass strength, and this can be an issue during the launch of the satellite because of the high kinematical and static loads occurring during that phase. In the present work we have investigated the possible use of Gorilla® glass (produced by Corning®), a chemical tempered glass that, thanks to its strength characteristics, would be ideal. The un-tempered glass foils were curved by means of an innovative hot slumping technique and subsequently chemically tempered. In this paper we show that the chemical tempering process applied to Gorilla® glass foils does not affect the surface micro-roughness of the mirrors. On the other end, the stress introduced by the tempering process causes a reduction in the amplitude of the longitudinal profile errors with a lateral size close to the mirror length. The effect of the overall shape changes in the final resolution performance of the glass mirrors was studied by simulating the glass foils integration with our innovative approach based on glass reinforcing ribs. The preliminary tests performed so far suggest that this approach has the potential to be applied to the X-ray telescopes of the next generation.

  5. Light weight optics made by glass thermal forming for future x-ray telescopes

    NASA Astrophysics Data System (ADS)

    Winter, Anita; Vongehr, Monika; Friedrich, Peter

    2010-07-01

    Future X-ray observatory missions, such as IXO or Gen-X, require grazing incidence optics of large collecting area in combination with a very good angular resolution. Wolter type I X-ray telescopes made of slumped glass segments could be a possible alternative to silicon pore optics. To achieve these requirements we develop slumping methods for high accuracy segments by experimental means. In particular, we follow the approach of indirect slumping and aim to produce parabola and hyperbola in one piece. In order to avoid internal stress in the glass segments the thermal expansion coefficient of the glass should closely match the thermal expansion of the mould material. Currently we focus on a combination of the alloy KOVAR for the mould and D263 for the glass; additionally a platinum-coated silica as mould material is studied. We investigate the behaviour of both materials during slumping in order to obtain the ideal environment for the slumping process. Additionally we report on the design of different metrology methods to measure the figure and thickness variations of the glass segments in visual light, e.g. interference, and on bearings used for shape measurements and integration.

  6. TES microcalorimeter development for future Japanese X-ray astronomy missions

    NASA Astrophysics Data System (ADS)

    Fujimoto, R.; Mitsuda, K.; Yamasaki, N. Y.; Iyomoto, N.; Oshima, T.; Takei, Y.; Futamoto, K.; Ichitsubo, T.; Fujimori, T.; Yoshida, K.; Ishisaki, Y.; Morita, U.; Koga, T.; Shinozaki, K.; Sato, K.; Takai, N.; Ohashi, T.; Kudo, H.; Sato, H.; Arakawa, T.; Kobayashi, H.; Izumi, T.; Ohtsuka, S.; Mori, K.; Shoji, S.; Osaka, T.; Homma, T.; Kuroda, Y.; Onishi, M.; Goto, M.; Beppu, F.; Tanaka, T.; Morooka, T.; Nakayama, S.; Chinone, K.

    2004-03-01

    We are developing a Ti/Au TES microcalorimeter array for future Japanese X-ray astronomy missions. The goal is an energy resolution of 2-5eV at 6keV, and an array of 100-1000 pixels to achieve a geometrical area of >1cm2 and a moderate spatial resolution simultaneously. The energy resolution was improved to ~6eV at 6keV with a very fast time constant (<100μs). To achieve a high coverage fraction, it is necessary to fabricate mushroom-shaped X-ray microabsorbers. We are developing an electrodeposition fabrication technique that is suitable for our process. Sn was used as absorber material, but the energy resolution was not good due to the existence of long-lived quasiparticles. Bi is also used, and the process is under optimization now. The readout strategy is to multiplex signals in the frequency domain, using a bridge circuit. So far, we succeeded in multiplexing two pixels modulated with 50 and 20kHz at 440mK. The energy resolution obtained at 110mK was 33eV(25kHz).

  7. First Year PIDDP Report on gamma-ray and x-ray spectroscopy: X-ray remote sensing and in situ spectroscopy for planetary exploration missions and gamma-ray remote sensing and in situ spectroscopy for planetary exploration missions

    NASA Technical Reports Server (NTRS)

    Mahdavi, M.; Giboni, K. L.; Vajda, S.; Schweitzer, J. S.; Truax, J. A.

    1994-01-01

    Detectors that will be used for planetary missions must have their responses calibrated in a reproducible manner. In addition, it is important to characterize a detector system at uneven portions of its life cycle, for example after exposure to different amounts of radiation. A calibration and response characterization facility has been constructed at Schlumberger-Doll Research for all types of gamma- and x-ray detectors that may be used for planetary measurement. This facility is currently being tested. Initial use is expected for the MARS 94 detectors. The facility will then also be available for calibrating other detectors as well as arrays of detectors such as the NEAR detector with its central Nal(TI) crystal surrounded with a large BGO crystal. Cadmium telluride detectors are investigated for applications in space explorations. These detectors show an energy resolution of 5 keV for the 122 keV 57Co line. Earlier reported polarization effects are not observed. The detectors can be used at temperatures up to 100 C, although with reduced energy resolution. The thickness of standard detectors is limited to 2 mm. These detectors become fully efficient at bias voltages above 200 V. Initial results for a 1 cm thick detector show that the quality of the material is inferior to the thinner standard detectors and hole trapping affects the pulse height. A detailed characterization of the detector is in progress. Prototypes of photomultipliers based on a Channel Electron Multiplier (CEM) are being built to study their performance. Such photomultipliers promise better timing characteristics and a higher dynamic range while being more compact and of lower in weight.

  8. Formation and X-ray emission from hot bubbles in planetary nebulae - I. Hot bubble formation

    NASA Astrophysics Data System (ADS)

    Toalá, J. A.; Arthur, S. J.

    2014-10-01

    We carry out high-resolution two-dimensional radiation-hydrodynamic numerical simulations to study the formation and evolution of hot bubbles inside planetary nebulae. We take into account the evolution of the stellar parameters, wind velocity and mass-loss rate from the final thermal pulses during the asymptotic giant branch (AGB) through to the post-AGB stage for a range of initial stellar masses. The instabilities that form at the interface between the hot bubble and the swept-up AGB wind shell lead to hydrodynamical interactions, photoevaporation flows and opacity variations. We explore the effects of hydrodynamical mixing combined with thermal conduction at this interface on the dynamics, photoionization, and emissivity of our models. We find that even models without thermal conduction mix significant amounts of mass into the hot bubble. When thermal conduction is not included, hot gas can leak through the gaps between clumps and filaments in the broken swept-up AGB shell and this depressurises the bubble. The inclusion of thermal conduction evaporates and heats material from the clumpy shell, which expands to seal the gaps, preventing a loss in bubble pressure. The dynamics of bubbles without conduction is dominated by the thermal pressure of the thick photoionized shell, while for bubbles with thermal conduction it is dominated by the hot, shocked wind.

  9. Indirect glass slumping for future x-ray missions: overview, status and progress

    NASA Astrophysics Data System (ADS)

    Winter, Anita; Breunig, Elias; Friedrich, Peter; Proserpio, Laura; Döhring, Thorsten

    2015-09-01

    Future X-ray telescopes aim for large effective area within the given mass limits of the launcher. A promising method is the hot shaping of thin glass sheets via a thermal slumping process. This paper presents the status and progress of the indirect glass slumping technology developed at the Max-Planck-Institut for extraterrestrial Physics (MPE). Recent developments in our research include the use of the mould material Cesic under vacuum, as well as the fabrication of a high-precision slumping mould, which meets the requirements of large, high angular resolution missions like ATHENA. We describe the way forward to optimise the slumping process on these materials, the force-free integration concept and its progress, as well as the first test on reflective coating application.

  10. Surface roughness evaluation on mandrels and mirror shells for future X-ray telescopes

    NASA Astrophysics Data System (ADS)

    Sironi, Giorgia; Spiga, D.

    2008-07-01

    More X-ray missions that will be operating in near future, like particular SIMBOL-X, e-Rosita, Con-X/HXT, SVOM/XIAO and Polar-X, will be based on focusing optics manufactured by means of the Ni electroforming replication technique. This production method has already been successfully exploited for SAX, XMM and Swift-XRT. Optical surfaces for X-ray reflection have to be as smooth as possible also at high spatial frequencies. Hence it will be crucial to take under control microroughness in order to reduce the scattering effects. A high rms microroughness would cause the degradation of the angular resolution and loss of effective area. Stringent requirements have therefore to be fixed for mirror shells surface roughness depending on the specific energy range investigated, and roughness evolution has to be carefully monitored during the subsequent steps of the mirror-shells realization. This means to study the roughness evolution in the chain mandrel, mirror shells, multilayer deposition and also the degradation of mandrel roughness following iterated replicas. Such a study allows inferring which phases of production are the major responsible of the roughness growth and could help to find solutions optimizing the involved processes. The exposed study is carried out in the context of the technological consolidation related to SIMBOL-X, along with a systematic metrological study of mandrels and mirror shells. To monitor the roughness increase following each replica, a multiinstrumental approach was adopted: microprofiles were analysed by means of their Power Spectral Density (PSD) in the spatial frequency range 1000-0.01 μm. This enables the direct comparison of roughness data taken with instruments characterized by different operative ranges of frequencies, and in particular optical interferometers and Atomic Force Microscopes. The performed analysis allowed us to set realistic specifications on the mandrel roughness to be achieved, and to suggest a limit for the

  11. Progress on indirect glass slumping for future x-ray telescope optics

    NASA Astrophysics Data System (ADS)

    Winter, Anita; Breunig, Elias; Friedrich, Peter; Proserpio, Laura

    2014-07-01

    Large X-ray telescopes for future observations need to combine a big collecting area with good angular resolution. Due to the mass limits of the launching rocket, light-weight materials are needed in order to enhance the collecting area in future telescopes. We study the development of mirror segments made from thin glass sheets which are shaped by thermal slumping. At MPE we follow the indirect approach which enables us the production of the parabolic and hyperbolic part of the Wolter type I mirrors in one piece. In our recent research we have used a test mould made of CeSiC™ for slumping processes in our lab furnace as well as in a heatable vacuum chamber, to avoid oxidation and air enclosure. Additional slumping tests in the vacuum furnace have been carried out using a Kovar mould and are compared with results under air. We describe the experimental set-up, the slumping process and the metrology methods and give an outlook on future activities.

  12. Characterization of a Prototype TES-Based Anti-coincidence Detector for Use with Future X-ray Calorimeter Arrays

    NASA Astrophysics Data System (ADS)

    Busch, S. E.; Yoon, W. S.; Adams, J. S.; Bailey, C. N.; Bandler, S. R.; Chervenak, J. A.; Eckart, M. E.; Ewin, A. J.; Finkbeiner, F. M.; Kelley, R. L.; Kilbourne, C. A.; Lee, S.-J.; Porst, J.-P.; Porter, F. S.; Sadleir, J. E.; Smith, S. J.; Sultana, M.

    2016-07-01

    For future X-ray observatories utilizing transition-edge sensor (TES) microcalorimeters, an anti-coincidence detector (anti-co) is required to discriminate X-ray (˜ 0.1-10 keV) signals from non-X-ray background events, such as ionizing particles. We have developed a prototype anti-co that utilizes TESs, which will be compatible with the TES focal-plane arrays planned for future X-ray observatories. This anti-co is based upon the cryogenic dark matter search II detector design. It is a silicon wafer covered with superconducting collection fins and TES microcalorimeters. Minimum ionizing particles deposit energy while passing through the silicon. The athermal phonons produced by these events are absorbed in the superconducting fins, breaking Cooper pairs. The resulting quasiparticles diffuse along the superconducting fin, producing a signal when they reach the TES. By determining a correlation between detections in the anti-co and the X-ray detector one can identify and flag these background events. We have fabricated and tested a single-channel prototype anti-co device on a 1.5 × 1.9 cm^2 chip. We have measured the signals in this device from photons of several energies between 1.5 and 60 keV, as well as laboratory background events, demonstrating a threshold ˜ 100 times lower than is needed to detect minimum ionizing particles.

  13. The Future of Spatially-Resolved Polychromatic Neutron and X-Ray Microdiffraction

    SciTech Connect

    Ice, Gene E

    2008-01-01

    Polychromatic microdiffraction is an emerging materials-characterization tool made practical by powerful X-ray and neutron sources, and by advanced optics and software. With polychromatic techniques, local crystalline properties including phase, texture (orientation), elastic strain, and defect density can be mapped with submicron spatial resolution in three dimensions. Here, we describe the evolving ability to nondestructively map local crystal structure in three dimensions and discuss how future advances will help address long-standing issues of inhomogeneous grain growth, deformation, fracture, and elastic strain. Current and future applications impact virtually all materials including electronic, solar, and light-emitting-diode (LED) materials, nanomaterials, structural materials, and joining materials. In addition, the ability to focus small beams on small samples dramatically increases signal-to-noise and greatly reduces the cost for extreme environmental chambers required for high-pressure, high-temperature, high-magnetic field or corrosive environments. Polychromatic techniques efficiently use source brilliance and minimize the required sample volume, which is essential for hard-to-make materials, irreplaceable materials, and for radioactive, toxic, or otherwise dangerous materials. New polychromatic neutron capabilities will significantly extend the range of samples that can be studied with neutrons and presents important new scientific opportunities for studies of magnetic materials, low Z elements, fragile crystal structures, and small samples in extreme environments.

  14. The Future of Spatially-Resolved Polychromatic Neutron and X-Ray Microdiffraction

    SciTech Connect

    Ice, Gene E.

    2009-09-25

    Polychromatic microdiffraction is an emerging materials-characterization tool made practical by powerful X-ray and neutron sources, and by advanced optics and software. With polychromatic techniques, local crystalline properties including phase, texture (orientation), elastic strain, and defect density can be mapped with submicron spatial resolution in three dimensions. Here, we describe the evolving ability to nondestructively map local crystal structure in three dimensions and discuss how future advances will help address long-standing issues of inhomogeneous grain growth, deformation, fracture, and elastic strain. Current and future applications impact virtually all materials including electronic, solar, and light-emitting-diode (LED) materials, nanomaterials, structural materials, and joining materials. In addition, the ability to focus small beams on small samples dramatically increases signal-to-noise and greatly reduces the cost for extreme environmental chambers required for high-pressure, high-temperature, high-magnetic field or corrosive environments. Polychromatic techniques efficiently use source brilliance and minimize the required sample volume, which is essential for hard-to-make materials, irreplaceable materials, and for radioactive, toxic, or otherwise dangerous materials. New polychromatic neutron capabilities will significantly extend the range of samples that can be studied with neutrons and presents important new scientific opportunities for studies of magnetic materials, low Z elements, fragile crystal structures, and small samples in extreme environments.

  15. SOFT-X RAY DIAGNOSTICS AND TREATMENTS FOR FUTURE REAL TIME APPLICATIONS

    SciTech Connect

    Pacella, D.; Mazon, D.

    2008-03-12

    This paper offers a preliminary review of the present diagnostics and data analysis techniques in the domain of Soft X-ray (SXR) emissions of fusion magnetic plasmas, including a short description of the theoretical background as well. Particular attention is devoted to the wide use of SXR tomography and impurity transport simulation. In their actual form, these techniques are not adequate to future real time applications. For this goal a step forward in the diagnosing and analysis of SXR emissions is required. The following part of the paper is therefore dedicated to the discussion of these improvements. The first one is the SXR tomography optimized for real time applications, like that one developed at Tore Supra (Cadarache, France). Fast 2-D tomographic inversions using different techniques (regularisation of Minimum Fisher, Maximum entropy, Zernicke polynomial expansions), will be optimized to be performed in a few millisecond time scale, crucial for MHD analysis, mode detection and localisation. The other goal to be pursued is the energy resolved imaging, now possible with a gas Micro Pattern Gas Detector with pixel read-out, as recently demonstrated at FTU (Frascati, Italy) and at NSTX (Princeton NJ, US), together with an ad hoc modeling of SXR emissions, compatible with future real time applications.

  16. X-ray binaries

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Satellite X-ray experiments and ground-based programs aimed at observation of X-ray binaries are discussed. Experiments aboard OAO-3, OSO-8, Ariel 5, Uhuru, and Skylab are included along with rocket and ground-based observations. Major topics covered are: Her X-1, Cyg X-3, Cen X-3, Cyg X-1, the transient source A0620-00, other possible X-ray binaries, and plans and prospects for future observational programs.

  17. Development of Instruments onboard ASTRO-H for Future X-ray Studies of Tori

    NASA Astrophysics Data System (ADS)

    Noda, H.

    2015-09-01

    The next astronomical X-ray satellite ASTRO-H will be launched by Japan Aerospace eXploration Agency (JAXA) in this Japanese fiscal year. It allows us to combine a simultaneous coverage of the 0.4-600 keV band, and a high energy-resolution spectroscopy in the 0.3-12 keV band with an FWHM energy resolution of < 7 eV at 6 keV. The wide-band capability is provided by several instruments; X-ray CCD cameras cover the 0.4-12 keV band at a focal plane of soft X-ray telescopes, a hard X-ray imager covers the 5-80 keV range with multilayer coating hard X-ray mirrors, and a non-focusing soft gamma-ray detector covers the 40-600 keV band. The high energy-resolution spectroscopy is realized by the X-ray micro-calorimeter array operated at 50 mK on a focal plane of the soft X-ray telescope. With the unprecedented performances, the ASTRO-H observations of active galactic nuclei are expected to give us important X-ray information about tori including their dynamics, size, ionization state and so on. In the present talk, we introduce the current status of developments of the instruments onboard ASTRO-H, especially focusing on the performance of the X-ray micro-calorimeter derived in the ongoing ground testing and calibration.

  18. The Prospects for Constraining Dark Energy withFuture X-ray Cluster Gas Mass Fraction Measurements

    SciTech Connect

    Rapetti, David; Allen, Steven W.

    2007-10-15

    We examine the ability of a future X-ray observatory, with capabilities similar to those planned for the Constellation-X mission, to constrain dark energy via measurements of the cluster X-ray gas mass fraction, fgas. We find that fgas measurements for a sample of {approx}500 hot (kT{approx}> 5keV), X-ray bright, dynamically relaxed clusters, to a precision of {approx}5 percent, can be used to constrain dark energy with a Dark Energy Task Force (DETF; Albrecht et al. 2006) figure of merit of 20-50. Such constraints are comparable to those predicted by the DETF for other leading, planned 'Stage IV' dark energy experiments. A future fgas experiment will be preceded by a large X-ray or SZ survey that will find hot, X-ray luminous clusters out to high redshifts. Short 'snapshot' observations with the new X-ray observatory should then be able to identify a sample of {approx}500 suitably relaxed systems. The redshift, temperature and X-ray luminosity range of interest has already been partially probed by existing X-ray cluster surveys which allow reasonable estimates of the fraction of clusters that will be suitably relaxed for fgas work to be made; these surveys also show that X-ray flux contamination from point sources is likely to be small for the majority of the targets of interest. Our analysis uses a Markov Chain Monte Carlo method which fully captures the relevant degeneracies between parameters and facilities the incorporation of priors and systematic uncertainties in the analysis. We explore the effects of such uncertainties, for scenarios ranging from optimistic to pessimistic. We conclude that the fgas experiment offers a competitive and complementary approach to the best other large, planned dark energy experiments. In particular, the fgas experiment will provide tight constraints on the mean matter and dark energy densities, with a peak sensitivity for dark energy work at redshifts midway between those of supernovae and baryon acoustic oscillation

  19. Recent results and future plans for a 45 actuator adaptive x-ray optics experiment at the advanced light source

    SciTech Connect

    Brejnholt, Nicolai F. Poyneer, Lisa A.; Hill, Randal M.; Pardini, Tommaso; Hagler, Lisle; Jackson, Jessie; Jeon, Jae; McCarville, Thomas J.; Palmer, David W.; Celestre, Richard; Brooks, Audrey D.

    2016-07-27

    We report on the current status of the Adaptive X-ray Optics project run by Lawrence Livermore National Laboratory (LLNL). LLNL is collaborating with the Advanced Light Source (ALS) to demonstrate a near real-time adaptive X-ray optic. To this end, a custom-built 45 cm long deformable mirror has been installed at ALS beamline 5.3.1 (end station 2) for a two-year period that started in September 2014. We will outline general aspects of the instrument, present results from a recent experimental campaign and touch on future plans for the project.

  20. TES-based microcalorimeter for future X-ray astronomy missions. Software development for instrument calibration

    NASA Astrophysics Data System (ADS)

    Fraga-Encinas, R.; Cobo, B.; Ceballos, M.; Schuurmans, J.; van der Kuur, J.; Carrera, F.; Barcons, X.

    2013-05-01

    The XMS (X-ray Microcalorimeter Spectrometer) is an instrument prototype with imaging capability in X-rays and high-spectral resolution. This instrument is a microcalorimeter based on transition edge sensors. As part of the Spanish contribution to the advancement of the XMS, we present the work carried out by the X-ray astronomy group at the Instituto de Física de Cantabria in collaboration with The Netherlands Institute for Space Research. The main work hereby presented includes the development and testing of software for this prototype with the purpose of instrument calibration and characterization, X-ray pulse detection and energy resolution calculations (Bergmann 2004, Tekst. Proefschrift Universiteit Utrecht; Boyce et al. 1999, Proc SPIE 3765; Den Herder et al. 2011, SRON-XMS-RP-2011-033; ATHENA Assessment Study Report, ESA/SRE(2011)17)

  1. X-ray Free-Electron Lasers - Present and Future Capabilities [Invited

    SciTech Connect

    Galayda, John; Ratner, John Arthur:a Daniel F.; White, William E.; /SLAC

    2011-11-16

    The Linac Coherent Light Source is now in operation as an X-ray free-electron laser (FEL) user facility. It produces coherent pulses of 550-10,000 eV X-rays of duration adjustable from <10 fsto500 fs. Typical peak power is in excess of 20 GW. The facility will soon be joined by several X-ray FELs under construction around the world. This article will provide an abridged history of free-electron lasers, a description of some basic physics regarding free-electron laser light amplification, and an overview of the rapidly growing list of examples in which lasers will be used in the control and operation of X-ray FELs.

  2. X-ray free-electron lasers--present and future capabilities [Invited

    SciTech Connect

    Galayda, John N.; Arthur, John; Ratner, Daniel F.; White, William E.

    2010-11-15

    The Linac Coherent Light Source is now in operation as an X-ray free-electron laser (FEL) user facility. It produces coherent pulses of 550-10,000 eV X-rays of duration adjustable from <10 fs to 500 fs. Typical peak power is in excess of 20 GW. The facility will soon be joined by several X-ray FELs under construction around the world. This article will provide an abridged history of free-electron lasers, a description of some basic physics regarding free-electron laser light amplification, and an overview of the rapidly growing list of examples in which lasers will be used in the control and operation of X-ray FELs.

  3. X-ray diffraction tomography of polycrystalline materials: present and future (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Stock, Stuart R.; Almer, Jonathan D.; Birkedal, Henrik

    2016-10-01

    Scattered x-radiation can be used for computed tomographic reconstruction of the distribution of crystallographic phases within the interior of specimens, and diffraction patterns can be measured for each volume element (voxel) within a reconstructed slice. This modality has been applied to systems as diverse as mineralized tissues and inorganic composites. Use of high energy x-rays (E < 40 keV) offers advantages including the ability to study volumes deep with specimens and to sample large ranges of reciprocal space, i.e., many reflections. The bases of diffraction tomography are reviewed, and the power of the technique is illustrated by the results obtained for specimens containing: a) different materials (SiC/Al composite), b) different polytypes (calcite/aragonite in a bivalve attachment system); c) mixtures of nanocrystalline and amorphous phases; d) a single phase, but volumes with different lattice parameters (hydroxyapatite, hAp, the mineral in bone and tooth); e) a single phase containing a spatial distribution of crystallographic texture (bone); a single phase with a spatial distribution of strains produced by in situ loading (bone). Finally, challenges and future directions are discussed.

  4. Surface charging and x-ray emission from insulator surfaces induced by collisions with highly charged ions : relevance to cometary and planetary sp

    NASA Technical Reports Server (NTRS)

    Djuric, N.; Lozano, J. A.; Smith, S. J.; Chutjian, A.

    2005-01-01

    Characteristic X-ray emission lines are detected from simulants of comet surfaces as they undergo collisions with highly charged ions (HCIs). The HCI projectiles are O+2-O+7. Ion energies are varied in the range (2-7)q keV, where q is the ion charge state. The targets are the insulator minerals olivine, augite, and quartz. It is found that the emission of characteristic K-L, K-M X-rays appears to proceed during positive charging of the surface by the HCI beam. When one uses low-energy, flood-gun electrons to neutralize the surface charge, the X-ray emission is eliminated or greatly reduced, depending on the flood-gun current. Acceleration of background electrons onto the charged surface results in excitation of elemental transitions, including the K-L2 and K-L3 target X-ray emission lines of Mg and Si located spectroscopically at 1253.6 and 1739.4 eV, respectively. Also observed are emission lines from O, Na, Ca, Al, and Fe atoms in the target and charge-exchange lines via surface extraction of electrons by the O+q electric field. Good agreement is found in the ratio of the measured X-ray yields for Mg and Si relative to the ratio of their electron-impact K-shell ionization cross sections. The present study may serve as a guide to astronomers as to specific observing X-ray energies indicative of solar/stellar wind or magnetospheric ion interactions with a comet, planetary surface, or circumstellar dust.

  5. Surface charging and x-ray emission from insulator surfaces induced by collisions with highly charged ions : relevance to cometary and planetary sp

    NASA Technical Reports Server (NTRS)

    Djuric, N.; Lozano, J. A.; Smith, S. J.; Chutjian, A.

    2005-01-01

    Characteristic X-ray emission lines are detected from simulants of comet surfaces as they undergo collisions with highly charged ions (HCIs). The HCI projectiles are O+2-O+7. Ion energies are varied in the range (2-7)q keV, where q is the ion charge state. The targets are the insulator minerals olivine, augite, and quartz. It is found that the emission of characteristic K-L, K-M X-rays appears to proceed during positive charging of the surface by the HCI beam. When one uses low-energy, flood-gun electrons to neutralize the surface charge, the X-ray emission is eliminated or greatly reduced, depending on the flood-gun current. Acceleration of background electrons onto the charged surface results in excitation of elemental transitions, including the K-L2 and K-L3 target X-ray emission lines of Mg and Si located spectroscopically at 1253.6 and 1739.4 eV, respectively. Also observed are emission lines from O, Na, Ca, Al, and Fe atoms in the target and charge-exchange lines via surface extraction of electrons by the O+q electric field. Good agreement is found in the ratio of the measured X-ray yields for Mg and Si relative to the ratio of their electron-impact K-shell ionization cross sections. The present study may serve as a guide to astronomers as to specific observing X-ray energies indicative of solar/stellar wind or magnetospheric ion interactions with a comet, planetary surface, or circumstellar dust.

  6. Soft X-ray study of solar wind charge exchange from the Earth's magnetosphere : Suzaku observations and a future X-ray imaging mission concept

    NASA Astrophysics Data System (ADS)

    Ezoe, Y.; Ishisaki, Y.; Ohashi, T.; Ishikawa, K.; Miyoshi, Y.; Fujimoto, R.; Terada, N.; Kasahara, S.; Fujimoto, M.; Mitsuda, K.; Nishijo, K.; Noda, A.

    2013-12-01

    Soft X-ray observations of solar wind charge exchange (SWCX) emission from the Earth's magnetosphere using the Japanese X-ray astronomy satellite Suzaku are shown, together with our X-ray imaging mission concept to characterize the solar wind interaction with the magnetosphere. In recent years, the SWCX emission from the Earth's magnetosphere, originally discovered as unexplained noise during the soft X-ray all sky survey (Snowden et al. 1994), is receiving increased attention on studying geospace. The SWCX is a reaction between neutrals in exosphere and highly charged ions in the magnetosphere originated from solar wind. Robertson et al. (2005) modeled the SWCX emission as seen from an observation point 50 Re from Earth. In the resulting X-ray intensities, the magnetopause, bow shock and cusp were clearly visible. High sensitivity soft X-ray observation with CCDs onboard recent X-ray astronomy satellites enables us to resolve SWCX emission lines and investigate time correlation with solar wind as observed with ACE and WIND more accurately. Suzaku is the 5th Japanese X-ray astronomy satellite launched in 2005. The line of sight direction through cusp is observable, while constraints on Earth limb avoidance angle of other satellites often limits observable regions. Suzaku firstly detected the SWCX emission while pointing in the direction of the north ecliptic pole (Fujimoto et al. 2007). Using the Tsyganenko 1996 magnetic field model, the distance to the nearest SWCX region was estimated as 2-8 Re, implying that the line of sight direction can be through magnetospheric cusp. Ezoe et al. (2010) reported SWCX events toward the sub-solar side of the magnetosheath. These cusp and sub-solar side magnetosheath regions are predicted to show high SWCX fluxes by Robertson et al. (2005). On the other hand, Ishikawa et al. (2013) discovered a similarly strong SWCX event when the line of sight direction did not transverse these two regions. Motivated by these detections

  7. Defining X-Ray Diffraction Parameters for the Design and Operation of a Planetary-Surface Rock Analyzer

    NASA Technical Reports Server (NTRS)

    Metzger, Ellen P.; Keaten, Rendy; Marshall, John R.; Kojiro, Dan

    1996-01-01

    Our joint research effort was aimed at developing techniques for X-ray diffractometry that was being investigated by NASA as possible flight instrumentation for the exploration of Mars. SJSU would provide the use of in-house X-ray facilities for calibration of the instrumentation , and would provide technical expertise regarding interpretation of data acquired during both laboratory testing, and during field testing of instruments on the Marsokhod rover at Ames. Accomplishments are: (1) quantification of X-ray signals from rock surfaces using San Jose State University (SJSU) diffractometer; (2) development of criteria for fingerprinting rock samples using pattern recognition of diffraction spectra, and augmentation of diffraction data with X-ray fluorescence information; (3) calibration of NASA instrumentation using SJSU-generator data; and (4) assistance in the development, lab testing, and field deployment of the NASA instrument on the Russian Marsokhod roving vehicle designed for martian exploration.

  8. X-Ray Microanalysis and Electron Energy Loss Spectrometry in the Analytical Electron Microscope: Review and Future Directions

    NASA Technical Reports Server (NTRS)

    Goldstein, J. I.; Williams, D. B.

    1992-01-01

    This paper reviews and discusses future directions in analytical electron microscopy for microchemical analysis using X-ray and Electron Energy Loss Spectroscopy (EELS). The technique of X-ray microanalysis, using the ratio method and k(sub AB) factors, is outlined. The X-ray absorption correction is the major barrier to the objective of obtaining I% accuracy and precision in analysis. Spatial resolution and Minimum Detectability Limits (MDL) are considered with present limitations of spatial resolution in the 2 to 3 microns range and of MDL in the 0.1 to 0.2 wt. % range when a Field Emission Gun (FEG) system is used. Future directions of X-ray analysis include improvement in X-ray spatial resolution to the I to 2 microns range and MDL as low as 0.01 wt. %. With these improvements the detection of single atoms in the analysis volume will be possible. Other future improvements include the use of clean room techniques for thin specimen preparation, quantification available at the I% accuracy and precision level with light element analysis quantification available at better than the 10% accuracy and precision level, the incorporation of a compact wavelength dispersive spectrometer to improve X-ray spectral resolution, light element analysis and MDL, and instrument improvements including source stability, on-line probe current measurements, stage stability, and computerized stage control. The paper reviews the EELS technique, recognizing that it has been slow to develop and still remains firmly in research laboratories rather than in applications laboratories. Consideration of microanalysis with core-loss edges is given along with a discussion of the limitations such as specimen thickness. Spatial resolution and MDL are considered, recognizing that single atom detection is already possible. Plasmon loss analysis is discussed as well as fine structure analysis. New techniques for energy-loss imaging are also summarized. Future directions in the EELS technique will be

  9. X-Ray Microanalysis and Electron Energy Loss Spectrometry in the Analytical Electron Microscope: Review and Future Directions

    NASA Technical Reports Server (NTRS)

    Goldstein, J. I.; Williams, D. B.

    1992-01-01

    This paper reviews and discusses future directions in analytical electron microscopy for microchemical analysis using X-ray and Electron Energy Loss Spectroscopy (EELS). The technique of X-ray microanalysis, using the ratio method and k(sub AB) factors, is outlined. The X-ray absorption correction is the major barrier to the objective of obtaining I% accuracy and precision in analysis. Spatial resolution and Minimum Detectability Limits (MDL) are considered with present limitations of spatial resolution in the 2 to 3 microns range and of MDL in the 0.1 to 0.2 wt. % range when a Field Emission Gun (FEG) system is used. Future directions of X-ray analysis include improvement in X-ray spatial resolution to the I to 2 microns range and MDL as low as 0.01 wt. %. With these improvements the detection of single atoms in the analysis volume will be possible. Other future improvements include the use of clean room techniques for thin specimen preparation, quantification available at the I% accuracy and precision level with light element analysis quantification available at better than the 10% accuracy and precision level, the incorporation of a compact wavelength dispersive spectrometer to improve X-ray spectral resolution, light element analysis and MDL, and instrument improvements including source stability, on-line probe current measurements, stage stability, and computerized stage control. The paper reviews the EELS technique, recognizing that it has been slow to develop and still remains firmly in research laboratories rather than in applications laboratories. Consideration of microanalysis with core-loss edges is given along with a discussion of the limitations such as specimen thickness. Spatial resolution and MDL are considered, recognizing that single atom detection is already possible. Plasmon loss analysis is discussed as well as fine structure analysis. New techniques for energy-loss imaging are also summarized. Future directions in the EELS technique will be

  10. Evaluating Handheld X-Ray Fluorescence (XRF) Technology in Planetary Exploration: Demonstrating Instrument Stability and Understanding Analytical Constraints and Limits for Basaltic Rocks

    NASA Technical Reports Server (NTRS)

    Young, K. E.; Hodges, K. V.; Evans, C. A.

    2012-01-01

    While large-footprint X-ray fluorescence (XRF) instruments are reliable providers of elemental information about geologic samples, handheld XRF instruments are currently being developed that enable the collection of geochemical data in the field in short time periods (approx.60 seconds) [1]. These detectors are lightweight (1.3kg) and can provide elemental abundances of major rock forming elements heavier than Na. While handheld XRF detectors were originally developed for use in mining, we are working with commercially available instruments as prototypes to explore how portable XRF technology may enable planetary field science [2,3,4]. If an astronaut or robotic explorer visited another planetary surface, the ability to obtain and evaluate geochemical data in real-time would be invaluable, especially in the high-grading of samples to determine which should be returned to Earth. We present our results on the evaluation of handheld XRF technology as a geochemical tool in the context of planetary exploration.

  11. XMM-Newton X-Ray Observations of LkCa 15: A T Tauri Star with a Formative Planetary System

    NASA Astrophysics Data System (ADS)

    Skinner, Stephen L.; Güdel, Manuel

    2017-04-01

    High-resolution ground-based images of the T Tauri star LkCa 15 have revealed multiple companions that are thought to comprise a formative planetary system. The candidate protoplanets orbit at distances of ˜15-20 au within the dust-depleted inner region of the circumstellar disk. Because of its young age (˜1-4 Myr), LkCa 15 provides a benchmark system for testing planet-formation models. We detected LkCa 15 as a bright X-ray source in a short 10 ks Chandra observation in 2009. We report here new results obtained from a deeper 37 ks XMM-Newton observation in 2014. The new data provide better sampling in the time domain and improved sensitivity at low energies below 1 keV. Spectral fits with thermal emission models require at least two temperature components at kT cool ≈ 0.4 keV and kT hot ≈ 2.2 keV. The value of kT hot is about a factor of two less than inferred from Chandra, suggesting that the hot-component temperature is variable. The best-fit absorption column density is in good agreement with that expected from optical extinction estimates {A}{{V}} ≈ 1.3-1.7 mag. The intrinsic X-ray luminosity is L x (0.2-10 keV) = 3 × 1030 erg s-1. Estimates of the X-ray heating rate of the inner disk and protoplanets are sensitive to the assumed disk gas surface density for which recent ALMA observations give estimates {{{Σ }}}0,{gas} ˜102 g cm-2 at 1 au from the star. At such densities, X-ray heating is confined mainly to the upper disk layers and X-ray penetration through the disk midplane to the protoplanets at r ≈ 15-20 au is negligible.

  12. Balloon-borne hard x-ray imaging and future surveys

    NASA Astrophysics Data System (ADS)

    Grindlay, Jonathan E.

    Several payloads for hard X-ray (20-600 keV) imaging with coded aperture telescopes have been developed for balloon flight observations of cosmic x-ray sources. We briefly review the characteristics of these, particularly the EXITE2 system. The recent NASA program to develop an extended long duration (100d) balloon flight capability employing super-pressure balloons would allow a qualitatively new hard x-ray imaging experiment: the Energetic X-ray Imaging Survey Telescope-Long Integration Time Experiment (EXIST-LITE). The longer continuous viewing times (per source) available from an LDB platform than from low earth orbit would enable both surveys and objectives complementary to the EXIST mission proposed for a MIDEX satellite. We summarize the scientific objectives of EXIST-LITE, a possible instrumentation approach incorporating a large area array of Cd-Zn-Te (CZT) detectors, and our program for the development and balloon flight testing of relatively thick (5mm) CZT detector arrays.

  13. X-ray Polarimetry

    NASA Astrophysics Data System (ADS)

    Kallman, T.

    In spite of the recent advances in X-ray instrumentation, polarimetry remains an area which has been virtually unexplored in the last 20 years. The scientific motivation to study polarization has increased during this time: emission models designed to repro- duce X-ray spectra can be tested using polarization, and polarization detected in other wavelength bands makes clear predictions as to the X-ray polarization. Polarization remains the only way to infer geometrical properties of sources which are too small to be spatially resolved. At the same time, there has been recent progress in instrumen- tation which is likely to allow searches for X-ray polarization at levels significantly below what was possible for early detectors. In this talk I will review the history of X-ray polarimetry, discuss some experimental techniques and the scientific problems which can be addressed by future experiments.

  14. The future of high angular resolution x-ray optics for astronomy (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Gorenstein, Paul

    2017-05-01

    Beginning with the Einstein Observatory in 1978, continuing with ROSAT in the 1990's and currently the Chandra X-Ray Observatory, high angular resolution focusing telescopes have been the premier X-ray astronomy instruments of their time. However, as they have acquired larger area and improved angular resolution they have become increasingly massive and expensive. The successor to Chandra planned for the late 2020's currently named "Lynx" will rely on active optics to allow the use of much lower mass segmented mirrors with the goal of gaining an order of magnitude larger area than Chandra with a lower ratio of mass to effective area and perhaps slightly better angular resolution than Chandra's 0.5 arc second half power diameter and/or over a somewhat larger field. The goals for Lynx are probably at the limit of what is possible with grazing incidence X-ray optics. Success in the development of higher angular resolution, lower mass telescopes will come at the expense of effective area. A diffractive-refractive pair consisting of a Fresnel zone plate and a diffractive lens that transmits rather than reflects X-rays is capable in theory of achieving mili arc second resolution with a much lower ratio of mass to effective area than the grazing incidence reflective Wolter optics. However, the focal lengths of this system are thousands of kilometers necessitating formation flying between one spacecraft hosting the optics and another hosting the detectors, most likely in a Sun-Earth L2 orbit. The trajectory of one of the two spacecraft can be in a true orbit but the other must be powered by an ion engine to maintain the alignment. The growing interest in deep space astronaut operations may allow the ion engines to be replaced when depleted.

  15. Black hole accretion rings revealed by future X-ray spectroscopy

    NASA Astrophysics Data System (ADS)

    Sochora, V.; Karas, V.; Svoboda, J.; Dovčiak, M.

    2011-11-01

    Spectral features can arise by reflection of coronal X-rays on a black hole accretion disc. The resulting profile bears various imprints of a strong gravitational field acting on the light-emitting gas. The observed shape of the reflection line is formed by integrating contributions over a range of radii across the accretion disc plane, where the individual photons experience a different level of energy shifts, boosting and amplification by relativistic effects. These have to be convolved with the intrinsic emissivity of the line, which is a function of radius and the emission angle in the local frame. We study if the currently discussed instruments on-board X-ray satellites will be able to reveal the departure of the line radial emissivity from a simple smooth power-law function, which is often assumed in data fitting and its interpretation. Such a departure can be a result of excess emission occurring at a certain distance. This could be used to study variations with a radius of the line production or to constrain the position of the inner edge of the accretion disc. By simulating artificial data from a bright active galactic nucleus of a type 1 Seyfert galaxy (inclination ≃30°, X-ray flux ≃1-2 mCrab in a keV energy band) we show that the required sensitivity and energy resolution could be reached with a large area detector of the proposed Large Observatory for X-ray Timing mission. Galactic black holes will provide another category of potentially suitable targets if the relativistic spectral features are indeed produced by reflection from their accretion discs.

  16. A Future Generation High Angular Resolution X-ray Telescope Based Upon Physical Optics

    NASA Astrophysics Data System (ADS)

    Gorenstein, Paul

    2013-04-01

    Although the highest priority objective for the next major X-ray mission is high resolution spectroscopy we will ultimately want the next generation high angular resolution X-ray observatory. This author believes that the 0.5 arc second angular resolution of the Chandra X-Ray Observatory is likely to be close to the best that can be obtained with grazing incidence optics, especially with larger effective area. Telescopes based upon physical optics, diffraction and refraction that transmit rather than reflect X-rays can have an angular resolution of a mili arc second or better. Combining the diffractive and refractive components into one unit can neutralize the chromatic aberration of each individually over a ~15% bandwidth at 6 keV. The aperture could be divided into several diffractive-refractive pairs to broaden the bandwidth. Furthermore these telescopes would be very low cost, very light weight, and more tolerant of figure errors and surface roughness than grazing incidence telescopes. However, focal lengths are of the order of 1000 km, which requires a new mission architecture consisting of long distance formation-flying between two spacecraft, one hosting the optics, the other, the detector. One of the spacecraft requires propulsion, provided by, for example, ion engines to maintain the optics-detector alignment by counteracting gravity gradient forces, and for changing targets. Although their effective area can be large and their angular resolution very high diffractive-refractive telescopes are not necessarily more sensitive than Chandra because their large focal plane scale (1 mili arc second ~ 1 mm) subjects them to a higher level of cosmic ray background and their opacity results in a lower energy limit of 2 keV. The intrinsic field of view is wide but the large focal length scale and practical limits on the size of the detector array results in a small field of view.

  17. Future Development Trajectories for Imaging X-ray Spectrometers Based on Microcalorimeters

    NASA Astrophysics Data System (ADS)

    Kilbourne, Caroline; Bandler, S.

    2013-04-01

    Since their invention 30 years ago, the capability of X-ray microcalorimeters has increased steadily, with continual improvements in energy resolution, speed, and array size. Arrays of up to 1024 pixels have been produced, and resolution better than 1 eV at 1.5 keV has been achieved. These detectors can be optimized for the highest priority science, such as designing for the highest resolving power at low energies at the expense of dynamic range, or the greatest focal-plane coverage at the expense of speed. Three types of X-ray microcalorimeters presently dominate the field, each characterized by the thermometer technology. The first two types use temperature-sensitive resistors: semiconductors in the metal-insulator transition and superconductors operated in the superconducting-normal transition. The third type uses a magnetically coupled thermometer, and is at an earlier stage of development than the other two. The Soft X-ray Spectrometer (SXS) on Astro-H, expected to launch in 2015, will use an array of silicon thermistors with HgTe X-ray absorbers that will operate at 50 mK. Both the semiconductor and superconductor calorimeters have been implemented in small arrays. Kilopixel arrays of the superconducting calorimeters are being produced, and much larger arrays may require the non-dissipative advantage of magnetically coupled thermometers. I will project the development trajectories of these detectors and their read-out technologies and assess what their capabilities and limitations will be 10 - 20 years from now.

  18. Proportional counter for X-ray analysis of lunar and planetary surfaces. [a position sensitive scintillating imaging proportional counter

    NASA Technical Reports Server (NTRS)

    1979-01-01

    A position sensitive proportional scintillation detector was developed and evaluated for use in applications involving X-ray imaging as well as spectroscopy. Topics covered include limitations of the proportional scintillation counter for use in space; purification of the xenon gas in the detector, and the operation of the detector system. Results show that the light signal in a proportional scintillation detector remains well localized. With modest electric fields in xenon, the primary electrons from a photoelectric absorption of an X-ray can be brought a distance of a few millimeters to a higher field region without spreading more than a millimeter or so. Therefore, it is possible to make a proportional scintillation detector with good position sensitivity that could be used to calibrate out the difference in light collection over its sensitive volume.

  19. Miniature lightweight X-ray optics (MiXO) for surface elemental composition mapping of asteroids and comets

    NASA Astrophysics Data System (ADS)

    Hong, Jaesub; Romaine, Suzanne

    2016-02-01

    The compositions of diverse planetary bodies are of fundamental interest to planetary science, providing clues to the formation and evolutionary history of the target bodies and the solar system as a whole. Utilizing the X-ray fluorescence unique to each atomic element, X-ray imaging spectroscopy is a powerful diagnostic tool of the chemical and mineralogical compositions of diverse planetary bodies. Until now the mass and volume of focusing X-ray optics have been too large for resource-limited in situ missions, so near-target X-ray observations of planetary bodies have been limited to simple collimator-type X-ray instruments. We introduce a new Miniature lightweight Wolter-I focusing X-ray Optics (MiXO) using metal-ceramic hybrid X-ray mirrors based on electroformed nickel replication and plasma thermal spray processes. MiXO can enable compact, powerful imaging X-ray telescopes suitable for future planetary missions. We illustrate the need for focusing X-ray optics in observing relatively small planetary bodies such as asteroids and comet nuclei. We present a few example configurations of MiXO telescopes and demonstrate their superior performance in comparison to an alternative approach, micro-pore optics, which is being employed for the first planetary focusing X-ray telescope, the Mercury Imaging X-ray Spectrometer-T onboard Bepicolumbo. X-ray imaging spectroscopy using MiXO will open a large new discovery space in planetary science and will greatly enhance our understanding of the nature and origin of diverse planetary bodies.

  20. High angular resolution X-ray astronomy in the next 50 years. Back to the future

    NASA Astrophysics Data System (ADS)

    Gorenstein, P.

    The 0.5 arc second angular resolution of the Chandra X-Ray Observatory is likely to be the best that can be obtained with grazing incidence optics, especially when larger effective area is required. We describe a telescope concept based upon transmitting diffractive-refractive optics that appears to be capable of providing better than mili arc second angular resolution. However, focal lengths are of the order of 1000 km, which requires long distance formation-flying between two spacecraft. In order to counteract gravity gradient forces to maintain alignment of optics with the detector and change targets,one of the spacecraft must contain engines for propulsion.

  1. MapX An In Situ, Full-frame X-Ray Spectroscopic Imager for Planetary Science and Astrobiology

    NASA Technical Reports Server (NTRS)

    Blake, David; Sarrazin, Philippe; Thompson, Kathleen; Bristow, Thomas

    2017-01-01

    Microbial life exploits micron-scale disequilibria at boundaries where valence, chemical potential, pH, Eh, etc. vary on a length scale commensurate with the organisms - 10's to 100's of microns. The detection of accumulations of the biogenic elements C,N,O,P,S at appropriate concentrations on or in a mineral/ice substrate would constitute permissive evidence of extant life, but context is also required. Does the putative biosignature exist under habitable conditions? Under what conditions of P, T, and chemical potential was the host mineralogy formed? MapX is an in situ robotic spacecraft instrument that images the biogenic elements C, N, O, P, S, as well as the cations of the rock-forming minerals (Na, Mg, Al, Si, K, Ca, Ti, Cr, Mn, Fe) and important anions such as Cl, Fl. MapX provides element maps with less than or equal to100 microns resolution over a 2.5 cm X 2.5 cm area, as well as quantitative XRF spectra from ground- or instrument-selected Regions of Interest (ROI). XRF spectra are converted to mineralogies using ground- or instrument-based algorithms. Either X-ray tube or radioisotope sources such as 244Cm (Alpha-particle and gamma- ray fluorescence) can be used. Fluoresced sample Xrays are imaged onto an X-ray sensitive CCD through an X-ray MicroPore Optic (MPO). The MapX design as well as baseline performance requirements for a MapX instrument intended for life detection / identification of habitable environments will be presented.

  2. X-ray calorimeters

    NASA Astrophysics Data System (ADS)

    Porter, F. Scott

    X-ray calorimeter instruments for astrophysics have seen rapid development since they were invented in 1984. The prime instrument on all currently planned X-ray spectroscopic observatories is based on calorimeter technology. This relatively simple detection concept that senses the energy of an incident photon by measuring the temperature rise of an absorber material at very low temperatures can form the basis of a very high-performance, non-dispersive spectrometer. State-of-theart calorimeter instruments have resolving powers of over 3000, large simultaneous bandpasses, and near unit efficiency. This coupled with the intrinsic imaging capability of a pixilated X-ray calorimeter array, allows true spectral-spatial instruments to be constructed. This chapter briefly reviews the detection scheme, the state of the art in X-ray calorimeter instruments and the future outlook for this technology.

  3. Fourier transform spectroscopy for future planetary missions

    NASA Astrophysics Data System (ADS)

    Brasunas, John; Kolasinski, John; Kostiuk, Ted; Hewagama, Tilak

    2017-01-01

    Thermal-emission infrared spectroscopy is a powerful tool for exploring the composition, temperature structure, and dynamics of planetary atmospheres; and the temperature of solid surfaces. A host of Fourier transform spectrometers (FTS) such as Mariner IRIS, Voyager IRIS, and Cassini CIRS from NASA Goddard have made and continue to make important new discoveries throughout the solar system. Future FTS instruments will have to be more sensitive (when we concentrate on the colder, outer reaches of the solar system), and less massive and less power-hungry as we cope with decreasing resource allotments for future planetary science instruments. With this in mind, we have developed CIRS-lite, a smaller version of the CIRS FTS for future planetary missions. We discuss the roadmap for making CIRS-lite a viable candidate for future planetary missions, including the recent increased emphasis on ocean worlds (Europa, Encelatus, Titan) and also on smaller payloads such as CubeSats and SmallSats.

  4. Hyper-velocity impact risk assessment and mitigation strategies in the context of future X-ray astronomy missions

    NASA Astrophysics Data System (ADS)

    Perinati, Emanuele; Rott, Martin; Santangelo, Andrea; Tenzer, Chris

    2017-06-01

    Future X-ray astronomy missions will be based on instruments with apertures much larger than those used up to now. Therefore, the risk posed by hyper-velocity dust grains in the space environment to the onboard instrumentation will increase, especially when a larger aperture is combined with a longer focal length. Starting from the lessons learned from the XMM and Swift satellites, we review the question of hyper-velocity impacts and discuss the expected impact-rate, risk of damage and possible mitigation strategies in the context of LOFT, eROSITA and ATHENA.

  5. Soft X-ray Studies of Pu Electronic Structure: Past Lessons and Future Directions

    SciTech Connect

    Tobin, J G; Yu, S W

    2008-02-07

    Photoelectron Spectroscopy (PES) and X-ray Absorption Spectroscopy (XAS, Figure 1) have contributed greatly to our improved understanding of Pu electronic structure. From these and related measurements, the following has been determined: (1) The Pu 5f spin-orbit splitting is large; (2) The number of Pu5f electrons is near 5; and (3) The Pu 5f spin-orbit splitting effect dominates 5f itineracy. Significant questions remain concerning the nature of Pu electronic structure. Perhaps the missing piece of the puzzle is the direct experimental determination of the unoccupied electronic structure using high energy inverse photoelectron spectroscopy or Bremstrahlung Isochromat Spectroscopy (BIS). Past BIS studies of Th and U indicate the feasibility and utility of Pu studies.

  6. The Swift Supergiant Fast X-Ray Transients Project:. [A Review, New Results and Future Perspectives

    NASA Technical Reports Server (NTRS)

    Romano, P.; Mangano, V.; Ducci, L.; Esposito, P.; Vercellone, S.; Bocchino, F.; Burrows, D. N.; Kennea, J. A.; Krimm, H. A.; Gehrels, N.; hide

    2013-01-01

    We present a review of the Supergiant Fast X-ray Transients (SFXT) Project, a systematic investigation of the properties of SFXTs with a strategy that combines Swift monitoring programs with outburst follow-up observations. This strategy has quickly tripled the available sets of broad-band data of SFXT outbursts, and gathered a wealth of out-of-outburst data, which have led us to a broad-band spectral characterization, an assessment of the fraction of the time these sources spend in each phase, and their duty cycle of inactivity. We present some new observational results obtained through our outburst follow-ups, as fitting examples of the exceptional capabilities of Swift in catching bright flares and monitor them panchromatically.

  7. A Review of the Handheld X-Ray Fluorescence Spectrometer as a Tool for Field Geologic Investigations on Earth and in Planetary Surface Exploration

    NASA Technical Reports Server (NTRS)

    Young, Kelsey E.; Evans, Cynthia A.; Hodges, Kip V.; Bleacher, Jacob E.; Graff, Trevor G.

    2016-01-01

    X-ray fluorescence (XRF) spectroscopy is a well-established and commonly used technique in obtaining diagnostic compositional data on geological samples. Recently, developments in X-ray tube and detector technologies have resulted in miniaturized, field-portable instruments that enable new applications both in and out of standard laboratory settings. These applications, however, have not been extensively applied to geologic field campaigns. This study investigates the feasibility of using developing handheld XRF (hXRF) technology to enhance terrestrial field geology, with potential applications in planetary surface exploration missions. We demonstrate that the hXRF is quite stable, providing reliable and accurate data continuously over a several year period. Additionally, sample preparation is proved to have a marked effect on the strategy for collecting and assimilating hXRF data. While the hXRF is capable of obtaining data that are comparable to laboratory XRF analysis for several geologically-important elements (such as Si, Ca, Ti, and K), the instrument is unable to detect other elements (such as Mg and Na) reliably. While this limits the use of the hXRF, especially when compared to laboratory XRF techniques, the hXRF is still capable of providing the field user with significantly improved contextual awareness of a field site, and more work is needed to fully evaluate the potential of this instrument in more complex geologic environments.

  8. A Review of the Handheld X-Ray Fluorescence Spectrometer as a Tool for Field Geologic Investigations on Earth and in Planetary Surface Exploration

    NASA Technical Reports Server (NTRS)

    Young, Kelsey E.; Evans, Cynthia A.; Hodges, Kip V.; Bleacher, Jacob E.; Graff, Trevor G.

    2016-01-01

    X-ray fluorescence (XRF) spectroscopy is a well-established and commonly used technique in obtaining diagnostic compositional data on geological samples. Recently, developments in X-ray tube and detector technologies have resulted in miniaturized, field-portable instruments that enable new applications both in and out of standard laboratory settings. These applications, however, have not been extensively applied to geologic field campaigns. This study investigates the feasibility of using developing handheld XRF (hXRF) technology to enhance terrestrial field geology, with potential applications in planetary surface exploration missions. We demonstrate that the hXRF is quite stable, providing reliable and accurate data continuously over a several year period. Additionally, sample preparation is proved to have a marked effect on the strategy for collecting and assimilating hXRF data. While the hXRF is capable of obtaining data that are comparable to laboratory XRF analysis for several geologically-important elements (such as Si, Ca, Ti, and K), the instrument is unable to detect other elements (such as Mg and Na) reliably. While this limits the use of the hXRF, especially when compared to laboratory XRF techniques, the hXRF is still capable of providing the field user with significantly improved contextual awareness of a field site, and more work is needed to fully evaluate the potential of this instrument in more complex geologic environments.

  9. Scientific Needs for Future X-Ray Sources in the U.S.: A White Paper

    SciTech Connect

    Falcone , Roger; Stohr, Joachim; Bergmann, Uwe; Corlett, John; Galayda, John; Hastings, Jerry; Robert Hettel, Zahid Hussain; Kirz, Janos; McCurdy, Bill; Raubenheimer, Tor; Fernando Sannibale, John Seeman; Shen, Z.-X.; Schoenlein, Robert; Zholents, Alexander; /SLAC /LBL, Berkeley

    2008-10-22

    Many of the important challenges facing humanity, including developing alternative sources of energy and improving health, are being addressed by advances that demand the improved understanding and control of matter. While the visualization, exploration, and manipulation of macroscopic matter have long been technological goals, scientific developments in the twentieth century have focused attention on understanding matter on the atomic scale through the underlying framework of quantum mechanics. Of special interest is matter that consists of natural or artificial nanoscale building blocks defined either by atomic structural arrangements or by electron or spin formations created by collective correlation effects (Figure 1.1). The essence of the challenge to the scientific community has been expressed in five grand challenges for directing matter and energy recently formulated by the Basic Energy Sciences Advisory Committee. These challenges focus on increasing our understanding of, and ultimately control of, matter at the level of atoms, electrons, and spins, as illustrated in Figure 1.1. Meeting these challenges will require new tools that extend our reach into regions of higher spatial, temporal, and energy resolution. Since the fundamental interaction that holds matter together is of electromagnetic origin, it is intuitively clear that electromagnetic radiation is the critical tool in the study of material properties. On the level of atoms, electrons and spins, x rays have proved especially valuable.

  10. Scientific Needs for Future X-ray Sources in the U.S. -- A White Paper

    SciTech Connect

    Falcone, Roger; Stohr, Joachim; Bergmann, Uwe; Corlett, John; Galayda, John; Hastings, Jerry; Hettel, Bob; Hussain, Zahid; Kirz, Janos; McCurdy, Bill; Raubenheimer, Tor; Sannibale, Fernando; Seeman, John; Shen, Z.-X.; Schoenlein, Bob; Zholents, Alexander

    2008-10-16

    Many of the important challenges facing humanity, including developing alternative sources of energy and improving heath, are being addressed by advances that demand the improved understanding and control of matter. While the visualization, exploration, and manipulation of macroscopic matter have long been technological goals, scientific developments in the twentieth century have focused attention on understanding matter on the atomic scale through the underlying framework of quantum mechanics. Of special interest is matter that consists of natural or artificial nanoscale building blocks defined either by atomic structural arrangements or by electron or spin formations created by collective correlation effects. The essence of the challenge to the scientific community has been expressed in five grand challenges for directing matter and energy recently formulated by the Basic Energy Sciences Advisory Committee. These challenges focus on increasing our understanding of, and ultimately control of, matter at the level of atoms, electrons. and spins, as illustrated in Figure 1.1. Meeting these challenges will require new tools that extend our reach into regions of higher spatial, temporal, and energy resolution. Since the fundamental interaction that holds matter together is of electromagnetic origin, it is intuitively clear that electromagnetic radiation is the critical tool in the study of material properties. On the level of atoms, electrons and spins, x rays have proved especially valuable.

  11. [What future for chest x-ray against ultra-low-dose computed tomography?

    PubMed

    Ohana, M; Ludes, C; Schaal, M; Meyer, E; Jeung, M-Y; Labani, A; Roy, C

    2017-02-01

    Technological improvements, with iterative reconstruction at the foreground, have lowered the radiation dose of a chest CT close to that of a PA and lateral chest x-ray. This ultra-low dose chest CT (ULD-CT) has an image quality that is degraded on purpose, yet remains diagnostic in many clinical indications. Thus, its effectiveness is already validated for the detection and the monitoring of solid parenchymal nodules, for the diagnosis and monitoring of infectious lung diseases and for the screening of pleural lesions secondary to asbestos exposure. Its limitations are the analysis of the mediastinal structures, the severe obesity (BMI>35) and the detection of interstitial lesions. If it can replace the standard chest CT in these indications, all the more in situations where radiation dose is a major problem (young patients, repeated exams, screening), it progressively emerges as a first line alternative for chest radiograph, providing more data at a similar radiation cost. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  12. Diffraction efficiency of a replicated, flight-like off-plane reflection grating baselined for future X-ray missions

    NASA Astrophysics Data System (ADS)

    Miles, Drew; McEntaffer, Randall; McCoy, Jake; Tutt, James; DeRoo, Casey

    2017-01-01

    Future soft X-ray spectroscopy missions have science requirements that demand higher instrument throughput and higher resolution than currently available technology. A key element in such spectrometers are dispersive elements such as diffraction gratings. Our group at Penn State University develops and fabricates off-plane reflection gratings in an effort to achieve the level of performance required by future missions. We present here efficiency measurements made in the 0.3 - 1.5 keV energy band at the Advanced Light Source (ALS) synchrotron at Lawrence Berkley National Laboratory for one such grating, which was replicated using UV-nanoimprint techniques from a grating master fabricated using electron-beam lithography, plasma etching, and potassium hydroxide etching. These results represent the first successful demonstration of off-plane grating replicas produced via these fabrication techniques and provide baseline efficiency measurements for flight-like replicated gratings.

  13. Fourier transform spectroscopy for future planetary missions

    NASA Astrophysics Data System (ADS)

    Brasunas, John C.; Hewagama, Tilak; Kolasinski, John R.; Kostiuk, Theodor

    2015-11-01

    Thermal-emission infrared spectroscopy is a powerful tool for exploring the composition, temperature structure, and dynamics of planetary atmospheres; and the temperature of solid surfaces. A host of Fourier transform spectrometers (FTS) such as Mariner IRIS, Voyager IRIS, and Cassini CIRS from NASA Goddard have made and continue to make important new discoveries throughout the solar system.Future FTS instruments will have to be more sensitive (when we concentrate on the colder, outer reaches of the solar system), and less massive and less power-hungry as we cope with decreasing resource allotments for future planetary science instruments. With this in mind, NASA Goddard was funded via the Planetary Instrument Definition and Development Progrem (PIDDP) to develop CIRS-lite, a smaller version of the CIRS FTS for future planetary missions. Following the initial validation of CIRS-lite operation in the laboratory, we have been acquiring atmospheric data in the 8-12 micron window at the 1.2 m telescope at the Goddard Geophysical and Astronomical Observatory (GGAO) in Greenbelt, MD. Targets so far have included Earth's atmosphere (in emission, and in absorption against the moon), and Venus.We will present the roadmap for making CIRS-lite a viable candidate for future planetary missions.

  14. Soft X-Ray Studies of Pu Electronic Structure: Past Lessons From XAS and Future Direction With BIS

    SciTech Connect

    Tobin, J G; Yu, S W; Chung, B W; Waddill, G D; Kutepov, A L

    2008-12-10

    Synchrotron-radiation-based spectroscopies such as X-ray Absorption Spectroscopy (XAS) have contributed greatly to our improved understanding of Pu electronic structure. However, significant questions remain concerning the nature of Pu electronic structure. Perhaps the missing piece of the puzzle is the direct experimental determination of the unoccupied electronic structure using high energy inverse photoelectron spectroscopy (IPES) or Bremstrahlung Isochromat Spectroscopy (BIS). Past BIS studies of Th and U indicate the feasibility and utility of Pu studies. To this end, a new BIS capability has been developed in our laboratory. Electron stimulated emission of photons has been carried out using the XES-350 monochromator and detector system. Our preliminary results and future plans will be presented.

  15. LIMITS ON [O III] 5007 EMISSION FROM NGC 4472'S GLOBULAR CLUSTERS: CONSTRAINTS ON PLANETARY NEBULAE AND ULTRALUMINOUS BLACK HOLE X-RAY BINARIES IN GLOBULAR CLUSTERS

    SciTech Connect

    Peacock, Mark B.; Zepf, Stephen E.; Maccarone, Thomas J.

    2012-06-20

    We have searched for [O III] 5007 emission in high-resolution spectroscopic data from FLAMES/GIRAFFE Very Large Telescope observations of 174 massive globular clusters (GCs) in NGC 4472. No planetary nebulae (PNe) are observed in these clusters, constraining the number of PNe per bolometric luminosity, {alpha} < 0.8 Multiplication-Sign 10{sup -7} PN/L{sub Sun }. This is significantly lower than the rate predicted from stellar evolution, if all stars produce PNe. Comparing our results to populations of PNe in galaxies, we find most galaxies have a higher {alpha} than these GCs (more PNe per bolometric luminosity-though some massive early-type galaxies do have similarly low {alpha}). The low {alpha} required in these GCs suggests that the number of PNe per bolometric luminosity does not increase strongly with decreasing mass or metallicity of the stellar population. We find no evidence for correlations between the presence of known GC PNe and either the presence of low-mass X-ray binaries (LMXBs) or the stellar interaction rates in the GCs. This, and the low {alpha} observed, suggests that the formation of PNe may not be enhanced in tight binary systems. These data do identify one [O III] emission feature, this is the (previously published) broad [O III] emission from the cluster RZ 2109. This emission is thought to originate from the LMXB in this cluster, which is accreting at super-Eddington rates. The absence of any similar [O III] emission from the other clusters favors the hypothesis that this source is a black hole LMXB, rather than a neutron star LMXB with significant geometric beaming of its X-ray emission.

  16. X-ray Polarimetry: From the Early Days to an Outlook for the Future

    NASA Technical Reports Server (NTRS)

    Weisskopf, Martin C.

    2014-01-01

    We present a historical (and personal) overview beginning with the pioneering contributions of Professor R. Novick and the team at the Columbia Astrophysics Laboratory. We will end with our (biased) outlook for the future.

  17. Astronomical X-Ray Optics

    NASA Technical Reports Server (NTRS)

    Joy, M. K.

    2000-01-01

    Over the past two decades, grazing incidence optics have transformed observational x-ray astronomy into a major scientific discipline at the cutting edge of research in astrophysics and cosmology. This review summarizes the fundamental design principles of grazing incidence optics for astronomical applications, describes the capabilities of the current generation of x-ray telescopes, and explores several avenues of future development.

  18. The future of planetary defense

    NASA Astrophysics Data System (ADS)

    Mainzer, A.

    2017-04-01

    Asteroids and comets have impacted Earth in the past and will do so in the future. While the frequency of impacts is reasonably well understood on geologic timescales, it is difficult to predict the next sizeable impact on human timescales by extrapolation from population statistics alone. Fortunately, by identifying and tracking individual objects, we can make precise predictions of any potential close encounters with Earth. As more advance notice is provided, the range of possible mitigation options expands. While the chance of an impact is very small, the potential consequences can be severe, meaning that sensible risk reduction measures should be undertaken. By implementing surveys, the risk of an unforeseen impact can be greatly reduced: the first step is finding the objects. Fortunately, the worldwide community of professional and amateur astronomers has made significant progress in discovering large near-Earth objects (NEOs). More than 95% of NEOs capable of causing global devastation (objects larger than 1 km in diameter) have been discovered, and none of these pose an impact hazard in the near future. Infrastructure is in place to link observations and compute close approaches in real time. Interagency and international collaborations have been undertaken to strengthen cooperative efforts to plan potential mitigation and civil defense campaigns. Yet much remains to be done. Approximately 70% of NEOs larger than 140 m (large enough to cause severe regional damage) remain undiscovered. With the existing surveys, it will take decades to identify the rest. Progress can be accelerated by undertaking new surveys with improved sensitivity.Plain Language SummaryAsteroids and comets have impacted Earth in the past and will do so in the <span class="hlt">future</span>. Fortunately, by identifying and tracking them, we have the ability to predict any potential close encounters with Earth. By observing the sky repeatedly to search for near</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26207928','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26207928"><span>Contrast Media for <span class="hlt">X-ray</span> and Magnetic Resonance Imaging: Development, Current Status and <span class="hlt">Future</span> Perspectives.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Frenzel, Thomas; Lawaczeck, Rüdiger; Taupitz, Matthias; Jost, Gregor; Lohrke, Jessica; Sieber, Martin A; Pietsch, Hubertus</p> <p>2015-09-01</p> <p>Over the last 120 years, the extensive advances in medical imaging allowed enhanced diagnosis and therapy of many diseases and thereby improved the quality of life of many patient generations. From the beginning, all technical solutions and imaging procedures were combined with dedicated pharmaceutical developments of contrast media, to further enhance the visualization of morphology and physiology. This symbiosis of imaging hardware and contrast media development was of high importance for the development of modern clinical radiology. Today, all available clinically approved contrast media fulfill the highest requirements for clinical safety and efficacy. All new concepts to increase the efficacy of contrast media have also to consider the high clinical safety standards and cost of goods of current marketed contrast media. Nevertheless, diagnostic imaging will contribute significantly to the progresses in medicine, and new contrast media developments are mandatory to address the medical needs of the <span class="hlt">future</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://medlineplus.gov/ency/article/003810.htm','NIH-MEDLINEPLUS'); return false;" href="https://medlineplus.gov/ency/article/003810.htm"><span>Joint <span class="hlt">x-ray</span></span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p><span class="hlt">X-ray</span> - joint; Arthrography; Arthrogram ... <span class="hlt">x-ray</span> technologist will help you position the joint to be <span class="hlt">x-rayed</span> on the table. Once in place, pictures are taken. The joint may be moved into other positions for more ...</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_8 --> <div id="page_9" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="161"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.nhlbi.nih.gov/health/health-topics/topics/cxray','NIH-MEDLINEPLUS'); return false;" href="https://www.nhlbi.nih.gov/health/health-topics/topics/cxray"><span>Chest <span class="hlt">X</span> <span class="hlt">Ray</span>?</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... this page from the NHLBI on Twitter. Chest <span class="hlt">X</span> <span class="hlt">Ray</span> A chest <span class="hlt">x</span> <span class="hlt">ray</span> is a fast and painless imaging test that ... tissue scarring, called fibrosis. Doctors may use chest <span class="hlt">x</span> <span class="hlt">rays</span> to see how well certain treatments are working ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19940022916','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19940022916"><span>Cosmic <span class="hlt">x</span> <span class="hlt">ray</span> physics</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mccammon, Dan; Cox, D. P.; Kraushaar, W. L.; Sanders, W. T.</p> <p>1990-01-01</p> <p>The annual progress report on Cosmic <span class="hlt">X</span> <span class="hlt">Ray</span> Physics is presented. Topics studied include: the soft <span class="hlt">x</span> <span class="hlt">ray</span> background, proportional counter and filter calibrations, the new sounding rocket payload: <span class="hlt">X</span> <span class="hlt">Ray</span> Calorimeter, and theoretical studies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19940022917','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19940022917"><span>Cosmic <span class="hlt">x</span> <span class="hlt">ray</span> physics</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mccammon, Dan; Cox, D. P.; Kraushaar, W. L.; Sanders, W. T.</p> <p>1991-01-01</p> <p>The annual progress report on Cosmic <span class="hlt">X</span> <span class="hlt">Ray</span> Physics for the period 1 Jan. to 31 Dec. 1990 is presented. Topics studied include: soft <span class="hlt">x</span> <span class="hlt">ray</span> background, new sounding rocket payload: <span class="hlt">x</span> <span class="hlt">ray</span> calorimeter, and theoretical studies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://medlineplus.gov/ency/article/003802.htm','NIH-MEDLINEPLUS'); return false;" href="https://medlineplus.gov/ency/article/003802.htm"><span>Skull <span class="hlt">x-ray</span></span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p><span class="hlt">X-ray</span> - head; <span class="hlt">X-ray</span> - skull; Skull radiography; Head <span class="hlt">x-ray</span> ... Chernecky CC, Berger BJ. Radiography of skull, chest, and cervical spine - diagnostic. In: Chernecky CC, Berger BJ, eds. Laboratory Tests and Diagnostic Procedures . 6th ed. ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.radiologyinfo.org/en/gallery/index.cfm?video=1198','NIH-MEDLINEPLUS'); return false;" href="http://www.radiologyinfo.org/en/gallery/index.cfm?video=1198"><span>Chest <span class="hlt">X-Ray</span></span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... by Image/Video Gallery Your radiologist explains chest <span class="hlt">x-ray</span>. Transcript Welcome to Radiology Info dot org! Hello, ... you about chest radiography also known as chest <span class="hlt">x-rays</span>. Chest <span class="hlt">x-rays</span> are the most commonly performed ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1042048','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1042048"><span>Quadriwave Lateral Shearing Interferometry in an Achromatic and Continuously Self-imaging Regime for <span class="hlt">Future</span> <span class="hlt">X-ray</span> Phase Imaging</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>J Rizzi; T Weitkamp; N Guerineau; M Idir; P Mercere; G Druart; G Vincent; P da Silva; J Primont</p> <p>2011-12-31</p> <p>We present in this Letter a type of quadriwave lateral shearing interferometer for <span class="hlt">x-ray</span> phase imaging. This device is based on a phase chessboard, and we take advantage of the large spectrum of the source to produce interferograms with a propagation-invariant contrast. Such a grating has been created for hard <span class="hlt">x-ray</span> interferometry and experimentally tested on a synchrotron beamline at Soleil.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21499369','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21499369"><span>Quadriwave lateral shearing interferometry in an achromatic and continuously self-imaging regime for <span class="hlt">future</span> <span class="hlt">x-ray</span> phase imaging.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Rizzi, Julien; Weitkamp, Timm; Guérineau, Nicolas; Idir, Mourad; Mercère, Pascal; Druart, Guillaume; Vincent, Grégory; da Silva, Paulo; Primot, Jérôme</p> <p>2011-04-15</p> <p>We present in this Letter a type of quadriwave lateral shearing interferometer for <span class="hlt">x-ray</span> phase imaging. This device is based on a phase chessboard, and we take advantage of the large spectrum of the source to produce interferograms with a propagation-invariant contrast. Such a grating has been created for hard <span class="hlt">x-ray</span> interferometry and experimentally tested on a synchrotron beamline at Soleil.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25931095','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25931095"><span>High-resolution <span class="hlt">X-ray</span> emission spectroscopy with transition-edge sensors: present performance and <span class="hlt">future</span> potential.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Uhlig, J; Doriese, W B; Fowler, J W; Swetz, D S; Jaye, C; Fischer, D A; Reintsema, C D; Bennett, D A; Vale, L R; Mandal, U; O'Neil, G C; Miaja-Avila, L; Joe, Y I; El Nahhas, A; Fullagar, W; Gustafsson, F Parnefjord; Sundström, V; Kurunthu, D; Hilton, G C; Schmidt, D R; Ullom, J N</p> <p>2015-05-01</p> <p><span class="hlt">X-ray</span> emission spectroscopy (XES) is a powerful element-selective tool to analyze the oxidation states of atoms in complex compounds, determine their electronic configuration, and identify unknown compounds in challenging environments. Until now the low efficiency of wavelength-dispersive <span class="hlt">X-ray</span> spectrometer technology has limited the use of XES, especially in combination with weaker laboratory <span class="hlt">X-ray</span> sources. More efficient energy-dispersive detectors have either insufficient energy resolution because of the statistical limits described by Fano or too low counting rates to be of practical use. This paper updates an approach to high-resolution <span class="hlt">X-ray</span> emission spectroscopy that uses a microcalorimeter detector array of superconducting transition-edge sensors (TESs). TES arrays are discussed and compared with conventional methods, and shown under which circumstances they are superior. It is also shown that a TES array can be integrated into a table-top time-resolved <span class="hlt">X-ray</span> source and a soft <span class="hlt">X-ray</span> synchrotron beamline to perform emission spectroscopy with good chemical sensitivity over a very wide range of energies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ApJ...809...75M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ApJ...809...75M"><span>Solar-wind Ion-driven <span class="hlt">X-Ray</span> Emission from Cometary and <span class="hlt">Planetary</span> Atmospheres: Measurements and Theoretical Predictions of Charge-Exchange Cross-sections and Emission Spectra for O6+ + H2O, Co, Co2, Ch4, N2, NO, N2O, and Ar</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Machacek, J. R.; Mahapatra, D. P.; Schultz, D. R.; Ralchenko, Yu.; Moradmand, A.; El Ghazaly, M. O. A.; Chutjian, A.</p> <p>2015-08-01</p> <p>Relevant to modeling and understanding <span class="hlt">X-ray</span> emission from cometary and <span class="hlt">planetary</span> atmospheres, total cross-sections for 1.17 and 2.33 keV/u O6+ colliding with H2O, CO, CO2, CH4, N2, NO, N2O, and Ar have been measured for the processes of single, double, and triple charge exchanges. Using these measurements as benchmarks, synthetic emission spectra spanning the <span class="hlt">X-ray</span>, UV, and visible range have been calculated based on theoretical treatment of the transfer of between one and six electrons from the target neutrals to the projectile ion, followed by radiative and non-radiative decay of the highly excited states produced in these collisions. The results help add to the base of knowledge required to simulate ion-neutral processes in astrophysical environments; refine the present understanding of these fundamental atomic processes; and guide <span class="hlt">future</span> observations, laboratory measurements, and theoretical predictions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017LPICo1989.8088B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017LPICo1989.8088B"><span><span class="hlt">Planetary</span> Science Training for NASA's Astronauts: Preparing for <span class="hlt">Future</span> Human <span class="hlt">Planetary</span> Exploration</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bleacher, J. E.; Evans, C. A.; Graff, T. G.; Young, K. E.; Zeigler, R.</p> <p>2017-02-01</p> <p>Astronauts selected in 2017 and in <span class="hlt">future</span> years will carry out in situ <span class="hlt">planetary</span> science research during exploration of the solar system. Training to enable this goal is underway and is flexible to accommodate an evolving <span class="hlt">planetary</span> science vision.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19940030875','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19940030875"><span><span class="hlt">X-ray</span> remote sensing and in-situ spectroscopy for <span class="hlt">planetary</span> exploration missions and gamma-ray remote sensing and in-situ spectroscopy for <span class="hlt">planetary</span> exploration missions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mahdavi, M.; Giboni, K. L.; Vajda, S.; Schweitzer, J.</p> <p>1994-01-01</p> <p>Detectors that will be used for <span class="hlt">planetary</span> missions must have their responses calibrated in a reproducible manner. A calibration facility is being constructed at Schlumberger-Doll Research for gamma and <span class="hlt">x</span> <span class="hlt">ray</span> detectors. With this facility the detector response can be determined in an invariant and reproducible fashion. Initial use of the facility is expected for the MARS94 detectors. Work is continuing to better understand the rare earth oxyorthosilicates and to define their characteristics. This will allow a better use of these scintillators for <span class="hlt">planetary</span> missions. In a survey of scintillating materials two scintillators were identified as promising candidates besides GSO, LSO, and YSO. These are CdWO4 and CsI(Tl). It will be investigated if a detector with a better overall performance can be assembled with various photon converters. Considerable progress was achieved in photomultiplier design. The length of an 1 inch diameter PMT could be reduced from 4.2 to 2.5 inches without performance degradation. This technology is being employed in the gamma ray detector for the NEAR project. A further weight and size reduction of the detector package can be achieved with miniaturized integrated power supplies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://medlineplus.gov/ency/article/003804.htm','NIH-MEDLINEPLUS'); return false;" href="https://medlineplus.gov/ency/article/003804.htm"><span>Chest <span class="hlt">x-ray</span></span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>Chest radiography; Serial chest <span class="hlt">x-ray</span>; <span class="hlt">X-ray</span> - chest ... You stand in front of the <span class="hlt">x-ray</span> machine. You will be told to hold your breath when the <span class="hlt">x-ray</span> is taken. Two images are usually taken. You will ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009JInst...4.3012T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009JInst...4.3012T"><span>Pixel detectors for <span class="hlt">x-ray</span> imaging spectroscopy in space</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Treis, J.; Andritschke, R.; Hartmann, R.; Herrmann, S.; Holl, P.; Lauf, T.; Lechner, P.; Lutz, G.; Meidinger, N.; Porro, M.; Richter, R. H.; Schopper, F.; Soltau, H.; Strüder, L.</p> <p>2009-03-01</p> <p>Pixelated semiconductor detectors for <span class="hlt">X-ray</span> imaging spectroscopy are foreseen as key components of the payload of various <span class="hlt">future</span> space missions exploring the <span class="hlt">x-ray</span> sky. Located on the platform of the new Spectrum-Roentgen-Gamma satellite, the eROSITA (extended Roentgen Survey with an Imaging Telescope Array) instrument will perform an imaging all-sky survey up to an <span class="hlt">X-ray</span> energy of 10 keV with unprecedented spectral and angular resolution. The instrument will consist of seven parallel oriented mirror modules each having its own pnCCD camera in the focus. The satellite born <span class="hlt">X-ray</span> observatory SIMBOL-X will be the first mission to use formation-flying techniques to implement an <span class="hlt">X-ray</span> telescope with an unprecedented focal length of around 20 m. The detector instrumentation consists of separate high- and low energy detectors, a monolithic 128 × 128 DEPFET macropixel array and a pixellated CdZTe detector respectively, making energy band between 0.5 to 80 keV accessible. A similar concept is proposed for the next generation <span class="hlt">X-ray</span> observatory IXO. Finally, the MIXS (Mercury Imaging <span class="hlt">X-ray</span> Spectrometer) instrument on the European Mercury exploration mission BepiColombo will use DEPFET macropixel arrays together with a small <span class="hlt">X-ray</span> telescope to perform a spatially resolved <span class="hlt">planetary</span> XRF analysis of Mercury's crust. Here, the mission concepts and their scientific targets are briefly discussed, and the resulting requirements on the detector devices together with the implementation strategies are shown.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013SPIE.8884E..1QG','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013SPIE.8884E..1QG"><span>Slumping technique for the manufacturing of a representative <span class="hlt">x-ray</span> grazing incidence mirror module for <span class="hlt">future</span> space missions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ghigo, Mauro; Proserpio, Laura; Basso, Stefano; Citterio, Oberto; Civitani, Marta M.; Pareschi, Giovanni; Salmaso, Bianca; Sironi, Giorgia; Spiga, Daniele; Tagliaferri, Giampiero; Vecchi, Gabriele; Zambra, Alberto; Parodi, Giancarlo; Martelli, Francesco; Gallieni, Daniele; Tintori, Matteo; Bavdaz, Marcos; Wille, Eric; Ferrario, Ivan; Burwitz, Vadim</p> <p>2013-09-01</p> <p>The Astronomical Observatory of Brera (INAF-OAB, Italy), with the financing support of the European Space Agency (ESA), has concluded a study regarding a glass shaping technology for the production of grazing incidence segmented <span class="hlt">x-ray</span> optics. This technique uses a hot slumping phase, in which pressure is actively applied on thin glass foils being shaped, to form a cylindrical approximation of Wolter I <span class="hlt">x-ray</span> segments, and a subsequent cold slumping phase, in which the final Wolter I profile is then freeze into the glass segments during their integration in elemental <span class="hlt">X-ray</span> Optical Units. The final goal of this study was the manufacturing of a prototype containing a number of slumped pair plates (meaning parabola and hyperbola couples) having representative dimensions to be tested both in UV light and in <span class="hlt">x-rays</span> at the Panter facility (Germany). In this paper, the INAF-OAB slumping technique, comprising a shaping step and an integration step is described, together with the results obtained on the manufactured prototype modules: the first prototype was aimed to test the ad-hoc designed and built semi-automatic Integration MAchine (IMA) and debug its control software. The most complete module comprises 40 slumped segments of Schott D263 glass type of dimension 200 mm x 200 mm and thickness of 0.4 mm, slumped on Zerodur K20 mould and stacked together through glued BK7 glass structural ribs to form the first entire <span class="hlt">x-ray</span> optical module ever built totally composed by glass. A last prototype was aimed at demonstrate the use of Schott glass AF32 type instead of D263. In particular, a new hot slumping experimental set-up is described whose advantage is to permit a better contact between mould and glass during the shaping process. The integration procedure of the slumped segments into the elemental module is also reviewed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AAS...22321206A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AAS...22321206A"><span>The Neutron Star Interior Composition Explorer (NICER): <span class="hlt">Future</span> <span class="hlt">X-ray</span> Astrophysics from the International Space Station</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arzoumanian, Zaven; Gendreau, K.; NICER Team</p> <p>2014-01-01</p> <p>In April 2013, NASA announced the selection of its newest planned high-energy astrophysics mission, the Neutron star Interior Composition Explorer (NICER), expected to launch in late 2016. As a successor to the now-decommissioned but highly productive Rossi <span class="hlt">X-ray</span> Timing Explorer, NICER offers capabilities that will appeal to a large community of prospective users. We present an overview of the NICER mission, its core science agenda, and a brief discussion of NICER's anticipated contributions across an array of <span class="hlt">X-ray</span> astrophysics investigations, enabled by a proposed Guest Observer program. NICER is designed to probe the exotic interiors of neutron stars, revealing the fundamental physics of dense matter that exists nowhere else in nature, a longstanding unsolved problem. NICER's key approach consists of inferring neutron star masses and radii through time-resolved soft <span class="hlt">X-ray</span> spectroscopy of pulsars with millisecond spin periods. In addition to exploring neutron star structure, NICER will study dynamic phenomena powered by accretion and strong gravity, and the extreme physics of pulsar magnetospheres, perhaps the most powerful cosmic particle accelerators known. NICER is particularly timely given the tremendous rate of millisecond-pulsar discovery enabled by NASA's Fermi gamma-ray telescope. NICER brings together high-heritage technologies -- such as grazing-incidence foil optics and silicon drift detectors -- in an innovative configuration, and exploits established infrastructure on the International Space Station to offer a low-risk, highly capable instrument to the <span class="hlt">X-ray</span> astrophysics community. NICER's unique combination of photon time-tagging precision, energy resolution, and sensitivity in the soft <span class="hlt">X-ray</span> (0.2-12 keV) band represents both a novel capability for studying neutron stars and exploration of new discovery space in time-domain astrophysics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://medlineplus.gov/ency/article/003806.htm','NIH-MEDLINEPLUS'); return false;" href="https://medlineplus.gov/ency/article/003806.htm"><span>Thoracic spine <span class="hlt">x-ray</span></span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>Vertebral radiography; <span class="hlt">X-ray</span> - spine; Thoracic <span class="hlt">x-ray</span>; Spine <span class="hlt">x-ray</span>; Thoracic spine films; Back films ... care provider's office. You will lie on the <span class="hlt">x-ray</span> table in different positions. If the <span class="hlt">x-ray</span> ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011apra.prop..155B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011apra.prop..155B"><span>Development of Small-Pixel CZT Detectors for <span class="hlt">Future</span> High-Resolution Hard <span class="hlt">X-ray</span> Missions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Beilicke, Matthias</p> <p></p> <p>Owing to recent breakthroughs in grazing incidence mirror technology, next-generation hard <span class="hlt">X-ray</span> telescopes will achieve angular resolutions of between 5 and 10 arc seconds - about an order of magnitude better than that of the NuSTAR hard <span class="hlt">X-ray</span> telescope. As a consequence, the next generation of hard <span class="hlt">X-ray</span> telescopes will require pixelated hard <span class="hlt">X</span>- <span class="hlt">ray</span> detectors with pixels on a grid with a lattice constant of between 120 and 240 um. Additional detector requirements include a low energy threshold of less than 5 keV and an energy resolution of less than 1 keV. The science drivers for a high angular-resolution hard <span class="hlt">X-ray</span> mission include studies and measurements of black hole spins, the cosmic evolution of super-massive black holes, AGN feedback, and the behavior of matter at very high densities. We propose a R&D research program to develop, optimize and study the performance of 100-200 um pixel pitch CdTe and Cadmium Zinc Telluride (CZT) detectors of 1-2 mm thickness. Our program aims at a comparison of the performance achieved with CdTe and CZT detectors, and the optimization of the pixel, steering grid, and guard ring anode patterns. Although these studies will use existing ASICs (Application Specific Integrated Circuits), our program also includes modest funds for the development of an ultra-low noise ASIC with a 2-D grid of readout pads that can be directly bonded to the 100-200 um pixel pitch CdTe and CZT detectors. The team includes the Washington University group (Prof. M. Beilicke and Co-I Prof. H.S.W. Krawczynski et al.), and co-investigator G. De Geronimo at Brookhaven National Laboratory (BNL). The Washington University group has a 10 year track record of innovative CZT detector R&D sponsored by the NASA Astronomy and Physics Research and Analysis (APRA) program. The accomplishments to date include the development of CZT detectors with pixel pitches between 350 um and 2.5 mm for the ProtoExist, EXIST, and X-Calibur hard <span class="hlt">X-ray</span> missions with some of the best</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002APS..MARQ15010D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002APS..MARQ15010D"><span>Element-specific magnetic imaging with an <span class="hlt">x-ray</span> microscope with 25 nm resolution: recent results and <span class="hlt">future</span> goals</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Denbeaux, Gregory; Chao, Weilun; Pearson, Angelic; Schneider, Gerd; Kusinski, Greg; Fischer, Peter</p> <p>2002-03-01</p> <p>The XM-1 soft <span class="hlt">x-ray</span> microscope, located at the Advanced Light Source at Lawrence Berkeley National Laboratory has been used to image magnetization with 25 nm spatial resolution. The microscope illumination can be adjusted between 300 and 1800 eV allowing element-specific magnetic imaging with <span class="hlt">x-ray</span> magnetic circular dichroism contrast for various elements including for Fe, Co, Ni, and Gd. This has been demonstrated to have a high sensitivity, which allows imaging of magnetic layers as thin as 3 nm. Since the imaging is photon-based, the presence of an applied magnetic field during imaging does not disrupt the image formation. Currently, samples can be imaged in an applied field of up to 3000 Oe. We will show recent results of high-resolution, element specific imaging of various multilayers and patterned structures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://medlineplus.gov/ency/article/003808.htm','NIH-MEDLINEPLUS'); return false;" href="https://medlineplus.gov/ency/article/003808.htm"><span>Bone <span class="hlt">x-ray</span></span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... not being scanned. Alternative Names <span class="hlt">X-ray</span> - bone Images Skeleton Skeletal spine Osteogenic sarcoma - <span class="hlt">x-ray</span> References ... urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://medlineplus.gov/ency/article/003801.htm','NIH-MEDLINEPLUS'); return false;" href="https://medlineplus.gov/ency/article/003801.htm"><span>Dental <span class="hlt">x-rays</span></span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p><span class="hlt">X-ray</span> - teeth; Radiograph - dental; Bitewings; Periapical film; Panoramic film; Digital image ... dentist's office. There are many types of dental <span class="hlt">x-rays</span>. Some of them are: Bitewing. Shows the crown ...</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_9 --> <div id="page_10" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="181"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://medlineplus.gov/ency/imagepages/1057.htm','NIH-MEDLINEPLUS'); return false;" href="https://medlineplus.gov/ency/imagepages/1057.htm"><span><span class="hlt">X-ray</span> (image)</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p><span class="hlt">X-rays</span> are a form of ionizing radiation that can penetrate the body to form an image on ... will be shades of gray depending on density. <span class="hlt">X-rays</span> can provide information about obstructions, tumors, and other ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=high+AND+power+AND+laser&id=EJ123242','ERIC'); return false;" href="http://eric.ed.gov/?q=high+AND+power+AND+laser&id=EJ123242"><span><span class="hlt">X-Ray</span> Lasers</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Chapline, George; Wood, Lowell</p> <p>1975-01-01</p> <p>Outlines the prospects of generating coherent <span class="hlt">x</span> <span class="hlt">rays</span> using high-power lasers and indentifies problem areas in their development. Indicates possible applications for coherent <span class="hlt">x</span> <span class="hlt">rays</span> in the fields of chemistry, biology, and crystallography. (GS)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://medlineplus.gov/ency/article/003337.htm','NIH-MEDLINEPLUS'); return false;" href="https://medlineplus.gov/ency/article/003337.htm"><span><span class="hlt">X-ray</span></span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... image. For most <span class="hlt">x-rays</span>, the risk of cancer or defects is very low. Most experts feel that the benefits of appropriate <span class="hlt">x-ray</span> ... Geleijns J, Tack D. Medical physics: radiation risks. In: Adam A, Dixon AK, Gillard ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1336825','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1336825"><span><span class="hlt">X-Ray</span> Toolkit</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p></p> <p>2015-10-20</p> <p>Radiographic Image Acquisition & Processing Software for Security Markets. Used in operation of commercial <span class="hlt">x-ray</span> scanners and manipulation of <span class="hlt">x-ray</span> images for emergency responders including State, Local, Federal, and US Military bomb technicians and analysts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://medlineplus.gov/ency/article/003803.htm','NIH-MEDLINEPLUS'); return false;" href="https://medlineplus.gov/ency/article/003803.htm"><span>Sinus <span class="hlt">x-ray</span></span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>Paranasal sinus radiography; <span class="hlt">X-ray</span> - sinuses ... sinus <span class="hlt">x-ray</span> is taken in a hospital radiology department. Or the <span class="hlt">x-ray</span> may be taken ... Brown J, Rout J. ENT, neck, and dental radiology. In: Adam A, Dixon AK, Gillard JH Schaefer- ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://medlineplus.gov/ency/article/003811.htm','NIH-MEDLINEPLUS'); return false;" href="https://medlineplus.gov/ency/article/003811.htm"><span>Hand <span class="hlt">x-ray</span></span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p><span class="hlt">X-ray</span> - hand ... A hand <span class="hlt">x-ray</span> is taken in a hospital radiology department or your health care provider's office by an ... technician. You will be asked to place your hand on the <span class="hlt">x-ray</span> table, and keep it ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20050215494&hterms=Io&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DIo','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20050215494&hterms=Io&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DIo"><span><span class="hlt">X-Ray</span> Probes of Jupiter's Auroral Zones, Galilean Moons, and the Io Plasma Torus</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Elsner, R. F.; Ramsey, B. D.; Swartz, D. A.; Rehak, P.; Waite, J. H., Jr.; Cooper, J. F.; Johnson, R. E.</p> <p>2005-01-01</p> <p>Remote observations from the Earth orbiting Chandra <span class="hlt">X-ray</span> Observatory and the XMM-Newton Observatory have shown the the Jovian system is a rich and complex source of <span class="hlt">x-ray</span> emission. The planet's auroral zones and its disk are powerful sources of <span class="hlt">x-ray</span> emission, though with different origins. Chandra observations discovered <span class="hlt">x-ray</span> emission from the Io plasma torus and from the Galilean moons Io, Europa, and possibly Ganymede. The emission from the moons is due to bombardment of their surfaces by highly energetic magnetospheric protons, and oxygen and sulfur ions, producing fluorescent <span class="hlt">x-ray</span> emission lines from the elements in their surfaces against an intense background continuum. Although very faint when observed from Earth orbit, an imaging <span class="hlt">x-ray</span> spectrometer in orbit around the icy Galilean moons would provide a detail mapping of the elemental composition in their surfaces. Here we review the results of Chandra and XMM-Newton observations of the Jovian system and describe the characteristics of X-MIME, an imaging <span class="hlt">x-ray</span> spectrometer undergoing study for possible application to <span class="hlt">future</span> missions to Jupiter such as JIMO. X-MIME has the ultimate goal of providing detailed high-resolution maps of the elemental abundances of the surfaces of Jupiter's icy moons and Io, as well as detailed study of the <span class="hlt">x-ray</span> mission from the Io plasma torus, Jupiter's auroral zones, and the <span class="hlt">planetary</span> disk.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012APS..MARQ33002S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012APS..MARQ33002S"><span>Initial Results and <span class="hlt">Future</span> Plans for the Soft <span class="hlt">X-ray</span> Instrument for Materials at the Linac Coherent Light Source (LCLS)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schlotter, William; Krupin, Oleg; Minitti, Michael; Turner, Joshua</p> <p>2012-02-01</p> <p>For two years ultrafast high intensity <span class="hlt">x-ray</span> pulses have been available at the Linac Coherent Light Source, the <span class="hlt">x-ray</span> free electron laser at the SLAC National Accelerator Laboratory. The soft <span class="hlt">x-ray</span> instrument (SXR) operates at an energy range from 480eV-2000eV and features a plane grating monochromator as well as a bendable refocusing mirror system. The measured performance of the instrument will be presented as well as the <span class="hlt">future</span> direction for instrumentation development. [4pt] Acknowledgement: This research was carried out on the SXR Instrument at the Linac Coherent Light Source (LCLS), a division of SLAC National Accelerator Laboratory and an Office of Science user facility operated by Stanford University for the U.S. Department of Energy. The SXR Instrument is funded by a consortium whose membership includes the LCLS, Stanford University through the Stanford Institute for Materials Energy Sciences (SIMES), Lawrence Berkeley National Laboratory (LBNL), University of Hamburg through the BMBF priority program FSP 301, and the Center for Free Electron Laser Science (CFEL).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19880016895','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19880016895"><span><span class="hlt">Planetary</span> Geology: Goals, <span class="hlt">Future</span> Directions, and Recommendations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1988-01-01</p> <p><span class="hlt">Planetary</span> exploration has provided a torrent of discoveries and a recognition that planets are not inert objects. This expanded view has led to the notion of comparative planetology, in which the differences and similarities among <span class="hlt">planetary</span> objects are assessed. Solar system exploration is undergoing a change from an era of reconnaissance to one of intensive exploration and focused study. Analyses of <span class="hlt">planetary</span> surfaces are playing a key role in this transition, especially as attention is focused on such exploration goals as returned samples from Mars. To assess how the science of <span class="hlt">planetary</span> geology can best contribute to the goals of solar system exploration, a workshop was held at Arizona State University in January 1987. The participants discussed previous accomplishments of the <span class="hlt">planetary</span> geology program, assessed the current studies in <span class="hlt">planetary</span> geology, and considered the requirements to meet near-term and long-term exploration goals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20150007837&hterms=sets&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dsets','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20150007837&hterms=sets&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dsets"><span>Advanced <span class="hlt">Planetary</span> Protection Technologies for the Proposed <span class="hlt">Future</span> Mission Set</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Spry, J. Andy; Conley, Catharine A</p> <p>2013-01-01</p> <p><span class="hlt">Planetary</span> protection is the discipline of protecting solar system objects from harmful contamination resulting from the activities of interplanetary spacecraft, and of similarly protecting the Earth from uncontrolled release of a putative extra-terrestrial organism from returned extra-terrestrial samples. <span class="hlt">Planetary</span> protection requirements for Mars are becoming further refined as more is understood about the nature of the Martian environment as a potential habitat. Likewise, increased understanding of the limits of life on Earth is informing <span class="hlt">planetary</span> protection policy. This presentation will discuss recent technology developments, ongoing work and <span class="hlt">future</span> challenges of implementing <span class="hlt">planetary</span> protection for the proposed <span class="hlt">future</span> mission set.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/15015954','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/15015954"><span>Clocking Femtosecond <span class="hlt">X-Rays</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Cavalieri, A L; Fritz, D M; Lee, S H; Bucksbaum, P H; Reis, D A; Mills, D M; Pahl, R; Rudati, J; Fuoss, P H; Stephenson, G B; Lowney, D P; MacPhee, A G; Weinstein, D; Falcone, R W; Als-Nielsen, J; Blome, C; Ischebeck, R; Schlarb, H; Tschentscher, T; Schneider, J; Sokolowski-Tinten, K; Chapman, H N; Lee, R W; Hansen, T N; Synnergren, O; Larsson, J; Techert, S; Sheppard, J; Wark, J S; Bergh, M; Calleman, C; Huldt, G; der Spoel, D v; Timneanu, N; Hajdu, J; Bong, E; Emma, P; Krejcik, P; Arthur, J; Brennan, S; Gaffney, K J; Lindenberg, A M; Hastings, J B</p> <p>2004-10-08</p> <p>The Sub-Picosecond Pulse Source (SPPS) at the Stanford Linear Accelerator Center (SLAC) produces the brightest ultrafast <span class="hlt">x-ray</span> pulses in the world, and is the first to employ compressed femtosecond electron bunches for the <span class="hlt">x-ray</span> source. Both SPPS and <span class="hlt">future</span> <span class="hlt">X-ray</span> Free Electron Lasers (XFEL's) will use precise measurements of individual electron bunches to time the arrival of <span class="hlt">x-ray</span> pulses for time-resolved experiments. At SPPS we use electro-optic sampling (EOS) to perform these measurements. Here we present the first results using this method. An ultrafast laser pulse (135 fs) passes through an electro-optic crystal adjacent to the electron beam. The refractive index of the crystal is distorted by the strong electromagnetic fields of the ultra-relativistic electrons, and this transient birefringence is imprinted on the laser polarization. A polarizer decodes this signal, producing a time-dependent image of the compressed electron bunch. Our measurements yield the relative timing between an ultrafast optical laser and an ultrafast <span class="hlt">x-ray</span> pulse to within 60 fs, making it possible to use the SPPS to observe atomic-scale ultrafast dynamics initiated by laser-matter interaction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19705296','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19705296"><span><span class="hlt">X-ray</span> emission spectroscopy.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bergmann, Uwe; Glatzel, Pieter</p> <p>2009-01-01</p> <p>We describe the chemical information that can be obtained by means of hard <span class="hlt">X-ray</span> emission spectroscopy (XES). XES is presented as a technique that is complementary to <span class="hlt">X-ray</span> absorption spectroscopy (XAS) and that provides valuable information with respect to the electronic structure (local charge- and spin-density) as well as the ligand environment of a 3d transition metal. We address non-resonant and resonant XES and present results that were recorded on Mn model systems and the Mn(4)Ca-cluster in the oxygen evolving complex of photosystem II. A brief description of the instrumentation is given with an outlook toward <span class="hlt">future</span> developments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EL....10538002M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EL....10538002M"><span><span class="hlt">X-ray</span> tensor tomography</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Malecki, A.; Potdevin, G.; Biernath, T.; Eggl, E.; Willer, K.; Lasser, T.; Maisenbacher, J.; Gibmeier, J.; Wanner, A.; Pfeiffer, F.</p> <p>2014-02-01</p> <p>Here we introduce a new concept for <span class="hlt">x-ray</span> computed tomography that yields information about the local micro-morphology and its orientation in each voxel of the reconstructed 3D tomogram. Contrary to conventional <span class="hlt">x-ray</span> CT, which only reconstructs a single scalar value for each point in the 3D image, our approach provides a full scattering tensor with multiple independent structural parameters in each volume element. In the application example shown in this study, we highlight that our method can visualize sub-pixel fiber orientations in a carbon composite sample, hence demonstrating its value for non-destructive testing applications. Moreover, as the method is based on the use of a conventional <span class="hlt">x-ray</span> tube, we believe that it will also have a great impact in the wider range of material science investigations and in <span class="hlt">future</span> medical diagnostics. The authors declare no competing financial interests.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.radiologyinfo.org/en/gallery/index.cfm?video=1198','SCIGOVIMAGE-MEDLINEPLUS'); return false;" href="https://www.radiologyinfo.org/en/gallery/index.cfm?video=1198"><span>Chest <span class="hlt">X-Ray</span></span></a></p> <p><a target="_blank" href="http://www.nlm.nih.gov/medlineplus/videosandcooltools.html">MedlinePlus Videos and Cool Tools</a></p> <p></p> <p></p> <p>... Site Index A-Z Spotlight Recently posted: Anal Cancer Facet Joint Block Video: Lung Cancer Screening Video: Upper GI Tract <span class="hlt">X-ray</span> Video: ... of lung conditions such as pneumonia, emphysema and cancer. A chest <span class="hlt">x-ray</span> requires no special preparation. ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=Photons&pg=7&id=EJ300482','ERIC'); return false;" href="https://eric.ed.gov/?q=Photons&pg=7&id=EJ300482"><span><span class="hlt">X-ray</span> Spectrometry.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Markowicz, Andrzej A.; Van Grieken, Rene E.</p> <p>1984-01-01</p> <p>Provided is a selective literature survey of <span class="hlt">X-ray</span> spectrometry from late 1981 to late 1983. Literature examined focuses on: excitation (photon and electron excitation and particle-induced <span class="hlt">X-ray</span> emission; detection (wavelength-dispersive and energy-dispersive spectrometry); instrumentation and techniques; and on such quantitative analytical…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/6741731','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/biblio/6741731"><span><span class="hlt">X-ray</span> beamsplitter</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Ceglio, N.M.; Stearns, D.G.; Hawryluk, A.M.; Barbee, T.W. Jr.</p> <p>1987-08-07</p> <p>An <span class="hlt">x-ray</span> beamsplitter which splits an <span class="hlt">x-ray</span> beam into two coherent parts by reflecting and transmitting some fraction of an incident beam has applications for <span class="hlt">x-ray</span> interferometry, <span class="hlt">x-ray</span> holography, <span class="hlt">x-ray</span> beam manipulation, and <span class="hlt">x-ray</span> laser cavity output couplers. The beamsplitter is formed of a wavelength selective multilayer thin film supported by a very thin <span class="hlt">x-ray</span> transparent membrane. The beamsplitter resonantly transmits and reflects <span class="hlt">x-rays</span> through thin film interference effects. A thin film is formed of 5--50 pairs of alternate Mo/Si layers with a period of 20--250 A. The support membrane is 10--200 nm of silicon nitride or boron nitride. The multilayer/support membrane structure is formed across a window in a substrate by first forming the structure on a solid substrate and then forming a window in the substrate to leave a free-standing structure over the window. 6 figs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.mayoclinic.org/tests-procedures/x-ray/basics/definition/PRC-20009519?p=1&DSECTION=all','NIH-MEDLINEPLUS'); return false;" href="http://www.mayoclinic.org/tests-procedures/x-ray/basics/definition/PRC-20009519?p=1&DSECTION=all"><span><span class="hlt">X-Ray</span></span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... of gray. For some types of <span class="hlt">X-ray</span> tests, a contrast medium — such as iodine or barium — is introduced into your body to provide greater detail on the images. <span class="hlt">X-ray</span> technology is used to examine many parts of the ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://medlineplus.gov/ency/article/003815.htm','NIH-MEDLINEPLUS'); return false;" href="https://medlineplus.gov/ency/article/003815.htm"><span>Abdominal <span class="hlt">x-ray</span></span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>An abdominal <span class="hlt">x-ray</span> is an imaging test to look at organs and structures in the abdomen. Organs include the spleen, stomach, and intestines. When the test is done to look at the bladder and kidney structures, it is called a KUB (kidneys, ureters, bladder) <span class="hlt">x-ray</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/867118','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/867118"><span><span class="hlt">X-ray</span> beamsplitter</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Ceglio, Natale M.; Stearns, Daniel S.; Hawryluk, Andrew M.; Barbee, Jr., Troy W.</p> <p>1989-01-01</p> <p>An <span class="hlt">x-ray</span> beamsplitter which splits an <span class="hlt">x-ray</span> beam into two coherent parts by reflecting and transmitting some fraction of an incident beam has applications for <span class="hlt">x-ray</span> interferometry, <span class="hlt">x-ray</span> holography, <span class="hlt">x-ray</span> beam manipulation, and <span class="hlt">x-ray</span> laser cavity output couplers. The beamsplitter is formed of a wavelength selective multilayer thin film supported by a very thin <span class="hlt">x-ray</span> transparent membrane. The beamsplitter resonantly transmits and reflects <span class="hlt">x-rays</span> through thin film interference effects. A thin film is formed of 5-50 pairs of alternate Mo/Si layers with a period of 20-250 A. The support membrane is 10-200 nm of silicon nitride or boron nitride. The multilayer/support membrane structure is formed across a window in a substrate by first forming the structure on a solid substrate and then forming a window in the substrate to leave a free-standing structure over the window.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6017370','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6017370"><span><span class="hlt">X-ray</span> lasers</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Elton, R.C.</p> <p>1990-01-01</p> <p>This paper provides a source that surveys the fundamentals of <span class="hlt">x-ray</span> lasers and summarizes recent advances. The author emphasizes <span class="hlt">x-ray</span> lasers created using high temperature plasmas as the medium. Specific topics discussed included electron-collisional excitation pumping, plasma laser pumping, and gamma-ray lasers. Numerous literature references provided.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_10 --> <div id="page_11" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="201"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/7004480','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/7004480"><span><span class="hlt">X-ray</span> lasers</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Elton, R.C.</p> <p>1990-01-01</p> <p>This book is both an introduction to <span class="hlt">x-ray</span> lasers and a how-to-guide for specialists. It provides comprehensive overview and describes useful examples of analysis and experiments as background and guidance for researchers undertaking new laser designs. The book collects the knowledge and experience gained in two decades of <span class="hlt">x-ray</span> laser development.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=photons&pg=6&id=EJ300482','ERIC'); return false;" href="http://eric.ed.gov/?q=photons&pg=6&id=EJ300482"><span><span class="hlt">X-ray</span> Spectrometry.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Markowicz, Andrzej A.; Van Grieken, Rene E.</p> <p>1984-01-01</p> <p>Provided is a selective literature survey of <span class="hlt">X-ray</span> spectrometry from late 1981 to late 1983. Literature examined focuses on: excitation (photon and electron excitation and particle-induced <span class="hlt">X-ray</span> emission; detection (wavelength-dispersive and energy-dispersive spectrometry); instrumentation and techniques; and on such quantitative analytical…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150020932','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150020932"><span>Characterization of Apollo Regolith by <span class="hlt">X-Ray</span> and Electron Microbeam Techniques: An Analog for <span class="hlt">Future</span> Sample Return Missions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zeigler, Ryan A.</p> <p>2015-01-01</p> <p>The Apollo missions collected 382 kg of rock and regolith from the Moon; approximately 1/3 of the sample mass collected was regolith. Lunar regolith consists of well mixed rocks, minerals, and glasses less than 1-centimeter n size. The majority of most surface regolith samples were sieved into less than 1, 1-2, 2-4, and 4-10- millimiter size fractions; a portion of most samples was re-served unsieved. The initial characterization and classification of most Apollo regolith particles was done primarily by binocular microscopy. Optical classification of regolith is difficult because (1) the finest fraction of the regolith coats and obscures the textures of the larger particles, and (b) not all lithologies or minerals are uniquely identifiable optically. In recent years, we have begun to use more modern <span class="hlt">x-ray</span> beam techniques [1-3], coupled with high resolution 3D optical imaging techniques [4] to characterize Apollo and meteorite samples as part of the curation process. These techniques, particularly in concert with SEM imaging of less than 1-millimeter regolith grain mounts, allow for the rapid characterization of the components within a regolith.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1999ASPC..157..299M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1999ASPC..157..299M"><span><span class="hlt">X-ray</span> spectroscopy of magnetic CVs</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Matt, Giorgio</p> <p></p> <p>I discuss two topics in <span class="hlt">X-ray</span> spectroscopy of magnetic CVs: reflection from the white dwarf surface, and opacity effects in the post shock plasma. I also briefly mention <span class="hlt">future</span> observational perspectives, with particular emphasis on the Constellation <span class="hlt">X-ray</span> mission.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/862565','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/862565"><span><span class="hlt">X-ray</span> generator</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Dawson, John M.</p> <p>1976-01-01</p> <p>Apparatus and method for producing coherent secondary <span class="hlt">x-rays</span> that are controlled as to direction by illuminating a mixture of high z and low z gases with an intense burst of primary <span class="hlt">x-rays</span>. The primary <span class="hlt">x-rays</span> are produced with a laser activated plasma, and these <span class="hlt">x-rays</span> strip off the electrons of the high z atoms in the lasing medium, while the low z atoms retain their electrons. The neutral atoms transfer electrons to highly excited states of the highly striped high z ions giving an inverted population which produces the desired coherent <span class="hlt">x-rays</span>. In one embodiment, a laser, light beam provides a laser spark that produces the intense burst of coherent <span class="hlt">x-rays</span> that illuminates the mixture of high z and low z gases, whereby the high z atoms are stripped while the low z ones are not, giving the desired mixture of highly ionized and neutral atoms. To this end, the laser spark is produced by injecting a laser light beam, or a plurality of beams, into a first gas in a cylindrical container having an adjacent second gas layer co-axial therewith, the laser producing a plasma and the intense primary <span class="hlt">x-rays</span> in the first gas, and the second gas containing the high and low atomic number elements for receiving the primary <span class="hlt">x-rays</span>, whereupon the secondary <span class="hlt">x-rays</span> are produced therein by stripping desired ions in a neutral gas and transfer of electrons to highly excited states of the stripped ions from the unionized atoms. Means for magnetically confining and stabilizing the plasma are disclosed for controlling the direction of the <span class="hlt">x-rays</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://images.nasa.gov/#/details-PIA21061.html','SCIGOVIMAGE-NASA'); return false;" href="https://images.nasa.gov/#/details-PIA21061.html"><span><span class="hlt">X-Rays</span> from Pluto</span></a></p> <p><a target="_blank" href="https://images.nasa.gov/">NASA Image and Video Library</a></p> <p></p> <p>2016-09-14</p> <p>The first detection of Pluto in <span class="hlt">X-rays</span> has been made using NASA's Chandra <span class="hlt">X-ray</span> Observatory in conjunction with observations from NASA's New Horizons spacecraft. As New Horizons approached Pluto in late 2014 and then flew by the planet during the summer of 2015, Chandra obtained data during four separate observations. During each observation, Chandra detected low-energy <span class="hlt">X-rays</span> from the small planet. The main panel in this graphic is an optical image taken from New Horizons on its approach to Pluto, while the inset shows an image of Pluto in <span class="hlt">X-rays</span> from Chandra. There is a significant difference in scale between the optical and <span class="hlt">X-ray</span> images. New Horizons made a close flyby of Pluto but Chandra is located near the Earth, so the level of detail visible in the two images is very different. The Chandra image is 180,000 miles across at the distance of Pluto, but the planet is only 1,500 miles across. Pluto is detected in the <span class="hlt">X-ray</span> image as a point source, showing the sharpest level of detail available for Chandra or any other <span class="hlt">X-ray</span> observatory. This means that details over scales that are smaller than the <span class="hlt">X-ray</span> source cannot be seen here. Detecting <span class="hlt">X-rays</span> from Pluto is a somewhat surprising result given that Pluto - a cold, rocky world without a magnetic field - has no natural mechanism for emitting <span class="hlt">X-rays</span>. However, scientists knew from previous observations of comets that the interaction between the gases surrounding such <span class="hlt">planetary</span> bodies and the solar wind - the constant streams of charged particles from the sun that speed throughout the solar system -- can create <span class="hlt">X-rays</span>. The researchers were particularly interested in learning more about the interaction between the gases in Pluto's atmosphere and the solar wind. The New Horizon spacecraft carries an instrument designed to measure that activity up-close -- Solar Wind Around Pluto (SWAP) -- and scientists examined that data and proposed that Pluto contains a very mild, close-in bowshock, where the solar wind first</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=MSFC-0101745&hterms=model+dental&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dmodel%2Bdental','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=MSFC-0101745&hterms=model+dental&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dmodel%2Bdental"><span><span class="hlt">X-ray</span> crystallography</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2001-01-01</p> <p><span class="hlt">X-rays</span> diffracted from a well-ordered protein crystal create sharp patterns of scattered light on film. A computer can use these patterns to generate a model of a protein molecule. To analyze the selected crystal, an <span class="hlt">X-ray</span> crystallographer shines <span class="hlt">X-rays</span> through the crystal. Unlike a single dental <span class="hlt">X-ray</span>, which produces a shadow image of a tooth, these <span class="hlt">X-rays</span> have to be taken many times from different angles to produce a pattern from the scattered light, a map of the intensity of the <span class="hlt">X-rays</span> after they diffract through the crystal. The <span class="hlt">X-rays</span> bounce off the electron clouds that form the outer structure of each atom. A flawed crystal will yield a blurry pattern; a well-ordered protein crystal yields a series of sharp diffraction patterns. From these patterns, researchers build an electron density map. With powerful computers and a lot of calculations, scientists can use the electron density patterns to determine the structure of the protein and make a computer-generated model of the structure. The models let researchers improve their understanding of how the protein functions. They also allow scientists to look for receptor sites and active areas that control a protein's function and role in the progress of diseases. From there, pharmaceutical researchers can design molecules that fit the active site, much like a key and lock, so that the protein is locked without affecting the rest of the body. This is called structure-based drug design.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=MSFC-0101745&hterms=riesgos+radiologia+dental&qs=Ntx%3Dmode%2Bmatchany%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Driesgos%2Bradiologia%2Bdental','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=MSFC-0101745&hterms=riesgos+radiologia+dental&qs=Ntx%3Dmode%2Bmatchany%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Driesgos%2Bradiologia%2Bdental"><span><span class="hlt">X-ray</span> crystallography</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2001-01-01</p> <p><span class="hlt">X-rays</span> diffracted from a well-ordered protein crystal create sharp patterns of scattered light on film. A computer can use these patterns to generate a model of a protein molecule. To analyze the selected crystal, an <span class="hlt">X-ray</span> crystallographer shines <span class="hlt">X-rays</span> through the crystal. Unlike a single dental <span class="hlt">X-ray</span>, which produces a shadow image of a tooth, these <span class="hlt">X-rays</span> have to be taken many times from different angles to produce a pattern from the scattered light, a map of the intensity of the <span class="hlt">X-rays</span> after they diffract through the crystal. The <span class="hlt">X-rays</span> bounce off the electron clouds that form the outer structure of each atom. A flawed crystal will yield a blurry pattern; a well-ordered protein crystal yields a series of sharp diffraction patterns. From these patterns, researchers build an electron density map. With powerful computers and a lot of calculations, scientists can use the electron density patterns to determine the structure of the protein and make a computer-generated model of the structure. The models let researchers improve their understanding of how the protein functions. They also allow scientists to look for receptor sites and active areas that control a protein's function and role in the progress of diseases. From there, pharmaceutical researchers can design molecules that fit the active site, much like a key and lock, so that the protein is locked without affecting the rest of the body. This is called structure-based drug design.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19970009627','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19970009627"><span>The Integrated <span class="hlt">X-Ray</span> Spectrum of Galactic Populations of Luminous Supersoft <span class="hlt">X-Ray</span> Sources</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>DiStefano, R.; Becker, C. M.; Fabbiano, G.</p> <p>1996-01-01</p> <p>We compute the composite <span class="hlt">X-ray</span> spectrum of a population of unresolved SSS's in a spiral galaxy such as our own or M31. The sources are meant to represent the total underlying population corresponding to all sources which have bolometric luminosities in the range of 10(exp 37) - 10(exp 38) ergs/s and kT on the order of tens of eV. These include close-binary supersoft sources, symbiotic novae, and <span class="hlt">planetary</span> nebulae, for example. In order to determine whether the associated <span class="hlt">X-ray</span> signal would be detectable, we also 'seed' the galaxy with other types of <span class="hlt">X-ray</span> sources, specifically low-mass <span class="hlt">X-ray</span> binaries (LMXB's) and high-mass <span class="hlt">X-ray</span> binaries (HMXB's). We find that the total spectrum due to SSS's, LMXB's, and HMXB's exhibits a soft peak which owes its presence to the SSS population. Preliminary indications are that this soft peak may be observable.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://images.nasa.gov/#/details-0006699.html','SCIGOVIMAGE-NASA'); return false;" href="https://images.nasa.gov/#/details-0006699.html"><span>History of Chandra <span class="hlt">X-Ray</span> Observatory</span></a></p> <p><a target="_blank" href="https://images.nasa.gov/">NASA Image and Video Library</a></p> <p></p> <p>2001-01-01</p> <p>Left image: The <span class="hlt">x-ray</span> data from the Chandra <span class="hlt">X-Ray</span> Observatory (CXO) has revealed a bright central star surrounded by a cloud of multimillion-degree gas in the <span class="hlt">planetary</span> nebula known as the Cat's Eye. This CXO image, where the intensity of the <span class="hlt">x-ray</span> emission is correlated to the brightness of the orange coloring, captures the expulsion of material from a star that is expected to collapse into a white dwarf in a few million years. The intensity of <span class="hlt">x-rays</span> from the central star was unexpected, and it is the first time astronomers have seen such <span class="hlt">x-ray</span> emission from the central star of a <span class="hlt">planetary</span> nebula. Right image: An image of Cat's Eye taken by the Hubble Space Telescope (HST). By comparing the CXO data with that from the HST, researchers are able to see where the hotter, <span class="hlt">x-ray</span> emitting gas appears in relation to the cooler material seen in optical wavelengths by the HST. The CXO team found that the chemical abundance in the region of hot gas (its <span class="hlt">x-ray</span> intensity is shown in purple) was not like those in the wind from the central star and different from the outer cooler material (the red and green structures.) Although still incredibly energetic and hot enough to radiate <span class="hlt">x-rays</span>, CXO shows the hot gas to be somewhat cooler than scientists would have expected for such a system. CXO image credit: (NASA/UIUC/Y. Chu et al.) HST image credit: (NASA/HST)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/867755','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/867755"><span><span class="hlt">X-ray</span> laser</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Nilsen, Joseph</p> <p>1991-01-01</p> <p>An <span class="hlt">X-ray</span> laser (10) that lases between the K edges of carbon and oxygen, i.e. between 44 and 23 Angstroms, is provided. The laser comprises a silicon (12) and dysprosium (14) foil combination (16) that is driven by two beams (18, 20) of intense line focused (22, 24) optical laser radiation. Ground state nickel-like dysprosium ions (34) are resonantly photo-pumped to their upper <span class="hlt">X-ray</span> laser state by line emission from hydrogen-like silicon ions (32). The novel <span class="hlt">X-ray</span> laser should prove especially useful for the microscopy of biological specimens.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19840046172&hterms=gums&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dgums','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19840046172&hterms=gums&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dgums"><span><span class="hlt">X-ray</span> superbubbles</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cash, W.</p> <p>1983-01-01</p> <p>Four regions of the galaxy, the Cygnus Superbubble, the Eta Carina complex, the Orion/Eridanus complex, and the Gum Nebula, are discussed as examples of collective effects in the interstellar medium. All four regions share certain features, indicating a common structure. The selection effects which determine the observable <span class="hlt">X-ray</span> properties of the superbubbles are discussed, and it is demonstrated that only a very few more in our Galaxy can be detected in <span class="hlt">X</span> <span class="hlt">rays</span>. <span class="hlt">X-ray</span> observation of extragalactic superbubbles is shown to be possible but requires the capabilities of a large, high quality, AXAF class observatory.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.radiologyinfo.org/en/info.cfm?pg=abdominrad','NIH-MEDLINEPLUS'); return false;" href="https://www.radiologyinfo.org/en/info.cfm?pg=abdominrad"><span>Abdomen <span class="hlt">X-Ray</span> (Radiography)</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... News Physician Resources Professions Site Index A-Z <span class="hlt">X-ray</span> (Radiography) - Abdomen Abdominal <span class="hlt">x-ray</span> uses a very ... of an abdominal <span class="hlt">x-ray</span>? What is abdominal <span class="hlt">x-ray</span>? An <span class="hlt">x-ray</span> (radiograph) is a noninvasive medical ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26288956','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26288956"><span><span class="hlt">X-rays</span> and magnetism.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Fischer, Peter; Ohldag, Hendrik</p> <p>2015-09-01</p> <p>Magnetism is among the most active and attractive areas in modern solid state physics because of intriguing phenomena interesting to fundamental research and a manifold of technological applications. State-of-the-art synthesis of advanced magnetic materials, e.g. in hybrid structures paves the way to new functionalities. To characterize modern magnetic materials and the associated magnetic phenomena, polarized <span class="hlt">x-rays</span> have emerged as unique probes due to their specific interaction with magnetic materials. A large variety of spectroscopic and microscopic techniques have been developed to quantify in an element, valence and site-sensitive way properties of ferro-, ferri-, and antiferromagnetic systems, such as spin and orbital moments, and to image nanoscale spin textures and their dynamics with sub-ns time and almost 10 nm spatial resolution. The enormous intensity of <span class="hlt">x-rays</span> and their degree of coherence at next generation <span class="hlt">x-ray</span> facilities will open the fsec time window to magnetic studies addressing fundamental time scales in magnetism with nanometer spatial resolution. This review will give an introduction into contemporary topics of nanoscale magnetic materials and provide an overview of analytical spectroscopy and microscopy tools based on <span class="hlt">x-ray</span> dichroism effects. Selected examples of current research will demonstrate the potential and <span class="hlt">future</span> directions of these techniques.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20020068100&hterms=planets+like+earth+discovered&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dplanets%2Blike%2Bearth%2Bdiscovered','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20020068100&hterms=planets+like+earth+discovered&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dplanets%2Blike%2Bearth%2Bdiscovered"><span>Soft <span class="hlt">X-Ray</span> Emissions from Planets and Moons</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bhardwaj, A.; Gladstone, G. R.; Elsner, R. F.; Waite, J. H., Jr.; Grodent, D.; Lewis, W. S.; Crary, F. J.; Weisskopf, M. C.; Howell, R. R.; Johnson, R. E.; Six, N. Frank (Technical Monitor)</p> <p>2002-01-01</p> <p>The soft <span class="hlt">x-ray</span> energy band (less than 4 keV) is an important spectral regime for <span class="hlt">planetary</span> remote sensing, as a wide variety of solar system objects are now known to shine at these wavelengths. These include Earth, Jupiter, comets, moons, Venus, and the Sun. Earth and Jupiter, as magnetic planets, are observed to emanate strong <span class="hlt">x-ray</span> emissions from their auroral (polar) regions, thus providing vital information on the nature of precipitating particles and their energization processes in <span class="hlt">planetary</span> magnetospheres. <span class="hlt">X</span> <span class="hlt">rays</span> from low latitudes have also been observed on these planets, resulting largely from atmospheric scattering and fluorescence of solar <span class="hlt">x-rays</span>. Cometary <span class="hlt">x-rays</span> are now a well established phenomena, more than a dozen comets have been observed at soft <span class="hlt">x-ray</span> energies, with the accepted production mechanism being charge-exchange between heavy solar wind ions and cometary neutrals. Also, Lunar <span class="hlt">x-rays</span> have been observed and are thought to be produced by scattering and fluorescence of solar <span class="hlt">x-rays</span> from the Moon's surface. With the advent of sophisticated <span class="hlt">x-ray</span> observatories, e.g., Chandra and XMM-Newton, the field of <span class="hlt">planetary</span> <span class="hlt">x-ray</span> astronomy is advancing at a much faster pace. The Chandra <span class="hlt">X-ray</span> Observatory (CXO) has recently captured soft <span class="hlt">x-rays</span> from Venus. Venusian <span class="hlt">x-rays</span> are most likely produced through fluorescence of solar <span class="hlt">x-rays</span> by C and O atoms in the upper atmosphere. Very recently, using CXO we have discovered soft <span class="hlt">x-rays</span> from the moons of Jupiter-Io, Europa, and probably Ganymede. The plausible source of the <span class="hlt">x-rays</span> from the Galilean satellites is bombardment of their surfaces by energetic (greater than 10 KeV) ions from the inner magnetosphere of Jupiter. The Io plasma Torus (IPT) is also discovered by CXO to be a source of soft <span class="hlt">x-rays</span> by CXO have revealed a mysterious pulsating (period approx. 45 minutes) <span class="hlt">x-ray</span> hot spot is fixed in magnetic latitude and longitude and is magnetically connected to a region in the outer magnetosphere of Jupiter. These</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhDT........38C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhDT........38C"><span>Thin Films for <span class="hlt">X-ray</span> Optics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Conley, Raymond</p> <p></p> <p> Laue lens, however my advancements in MLL fabrication technology led to new generations of deposition instruments that were better suited. In order to re-purpose the APS Rotary Deposition System, a concept to upgrade the machine with a suborbital <span class="hlt">planetary</span> is discussed. The APS Modular Deposition System (MDS) is the state of the art instrument that was designed to keep APS at the forefront of <span class="hlt">x-ray</span> optics technology for the foreseeable <span class="hlt">future</span>. By including flexibility in the design, the machine is ideally suited for research on all types of multilayers and thin-films for <span class="hlt">x-ray</span> optics applications. A new method for in-situ surface metrology is presented which relies on the infrastructure provided by the MDS. The chapter concludes with discussion on several types of reflective multilayers that span a broad range of <span class="hlt">x-ray</span> wavelengths, from soft <span class="hlt">x-rays</span> (below 5-10 keV) to hard <span class="hlt">x-rays</span> (above 5-10keV). A method for fabrication of precision elliptically-figured mirrors called profile coating (conceived at the APS) is covered in Chapter 3. Profile-coating is a technique where a specially shaped mask is designed to partially obscure the sputtering source in order to produce a coating with a specially defined film thickness profile perpendicular to substrate translation. Source shape modeling and mask calculation is presented. Initially, Au was used as the filler material for profile coating, however I found that Pt offered better performance. Rh has also been used to fabricate profile-coated KB mirrors. Performance and commissioning results for the APS profile-coating deposition system (another machine designed by myself) is included. Chapter 4 covers my work on multilayer Laue lens. Motivation and current status are presented, and the nomenclature we devised to name the various MLL types is listed. Following this, a theoretical overview is provided. Important advancements I have spearhead in this field are included, such as the introduction of metal silicides, reactive</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22525613','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22525613"><span>SOLAR-WIND ION-DRIVEN <span class="hlt">X-RAY</span> EMISSION FROM COMETARY AND <span class="hlt">PLANETARY</span> ATMOSPHERES: MEASUREMENTS AND THEORETICAL PREDICTIONS OF CHARGE-EXCHANGE CROSS-SECTIONS AND EMISSION SPECTRA FOR O{sup 6+} + H{sub 2}O, CO, CO{sub 2}, CH{sub 4}, N{sub 2}, NO, N{sub 2}O, AND Ar</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Machacek, J. R.; Mahapatra, D. P.; Schultz, D. R.; Ralchenko, Yu.; Moradmand, A.; El Ghazaly, M. O. A.; Chutjian, A.</p> <p>2015-08-10</p> <p>Relevant to modeling and understanding <span class="hlt">X-ray</span> emission from cometary and <span class="hlt">planetary</span> atmospheres, total cross-sections for 1.17 and 2.33 keV/u O{sup 6+} colliding with H{sub 2}O, CO, CO{sub 2}, CH{sub 4}, N{sub 2}, NO, N{sub 2}O, and Ar have been measured for the processes of single, double, and triple charge exchanges. Using these measurements as benchmarks, synthetic emission spectra spanning the <span class="hlt">X-ray</span>, UV, and visible range have been calculated based on theoretical treatment of the transfer of between one and six electrons from the target neutrals to the projectile ion, followed by radiative and non-radiative decay of the highly excited states produced in these collisions. The results help add to the base of knowledge required to simulate ion-neutral processes in astrophysical environments; refine the present understanding of these fundamental atomic processes; and guide <span class="hlt">future</span> observations, laboratory measurements, and theoretical predictions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://medlineplus.gov/ency/article/003381.htm','NIH-MEDLINEPLUS'); return false;" href="https://medlineplus.gov/ency/article/003381.htm"><span><span class="hlt">X-ray</span> - skeleton</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... medlineplus.gov/ency/article/003381.htm <span class="hlt">X-ray</span> - skeleton To use the sharing features on this page, ... ray views may be uncomfortable. If the whole skeleton is being imaged, the test usually takes 1 ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=diffraction+AND+rays+AND+x&pg=3&id=EJ226271','ERIC'); return false;" href="https://eric.ed.gov/?q=diffraction+AND+rays+AND+x&pg=3&id=EJ226271"><span><span class="hlt">X-Ray</span> Diffraction.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Smith, D. K.; Smith, K. L.</p> <p>1980-01-01</p> <p>Reviews applications in research and analytical characterization of compounds and materials in the field of <span class="hlt">X-ray</span> diffraction, emphasizing new developments in applications and instrumentation in both single crystal and powder diffraction. Cites 414 references. (CS)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006SPIE.6266E..1AW','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006SPIE.6266E..1AW"><span>Developments in glass micro pore optics for <span class="hlt">x-ray</span> applications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wallace, Kotska; Collon, Maximilien; Bavdaz, Marcos; Fairbend, Ray; Séguy, Julien; Krumrey, Michael</p> <p>2006-06-01</p> <p>ESA is developing technologies for <span class="hlt">x-ray</span> imaging to reduce the mass and volume of <span class="hlt">future</span> missions. Applications of <span class="hlt">x-ray</span> optics are foreseen in <span class="hlt">future</span> <span class="hlt">planetary</span> <span class="hlt">x-ray</span> imagers, <span class="hlt">x-ray</span> timing observatories and in observatories for high-energy astrophysics. With reference to <span class="hlt">planetary</span> <span class="hlt">x-ray</span> imagers the use of glass micro-pore material is being investigated. This technology allows the formation of a monolithic, glass structure that can be used to focus <span class="hlt">x-rays</span> by glancing reflections off the pore walls. A technique to form <span class="hlt">x-ray</span> focusing plates that contain thousands of square micro-pores has been developed with Photonis. The square pores are formed in a process that fuses blocks of extruded square fibres, which can then be sliced, etched and slumped to form the segment of an optic with a specific radius. A proposed imager would be created from 2 optics, slumped with different radii, and mounted to form an approximation of a Wolter I optic configuration. Reflection can be improved by coating the channel surfaces with a heavy element, such as nickel. Continuing developments have been made to enhance the manufacturing processes and improve the characteristics of the manufactured <span class="hlt">x-ray</span> focusing plates, such as improved surface roughness and squareness of pore walls, improved pore alignment from fibre stacking through to optic segment slumping and development of pore wall coatings. In order to measure improvements <span class="hlt">x-ray</span> measurements are performed by ESA and cosine Research BV, using the BESSY-II synchrotron facility four-crystal monochromator beamline of the Physikalisch-Technische Bundesanstalt, on multifibres, sectors and slumped sectors. A probing beam is used to investigate a number of pores to determine <span class="hlt">x-ray</span> transmission, focussing characteristics as they relate to the overall transmission, <span class="hlt">x-ray</span> reflectivity of channel walls, radial alignment of fibres, slumping radius and fibre position in a fused block. SEM measurements and microscope inspection have also been used</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_11 --> <div id="page_12" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="221"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19940022733','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19940022733"><span>Cosmic <span class="hlt">x</span> <span class="hlt">ray</span> physics</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mccammon, Dan; Cox, D. P.; Kraushaar, W. L.; Sanders, W. T.</p> <p>1992-01-01</p> <p>This final report covers the period 1 January 1985 - 31 March 1992. It is divided into the following sections: the soft <span class="hlt">x-ray</span> background; proportional counter and filter calibrations; sounding rocket flight preparations; new sounding rocket payload: <span class="hlt">x-ray</span> calorimeter; and theoretical studies. Staff, publications, conference proceedings, invited talks, contributed talks, colloquia and seminars, public service lectures, and Ph. D. theses are listed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003AGUFM.P41B0413V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003AGUFM.P41B0413V"><span>Portable <span class="hlt">X-ray</span> Fluorescence Unit for Analyzing Crime Scenes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Visco, A.</p> <p>2003-12-01</p> <p>Goddard Space Flight Center and the National Institute of Justice have teamed up to apply NASA technology to the field of forensic science. NASA hardware that is under development for <span class="hlt">future</span> <span class="hlt">planetary</span> robotic missions, such as Mars exploration, is being engineered into a rugged, portable, non-destructive <span class="hlt">X-ray</span> fluorescence system for identifying gunshot residue, blood, and semen at crime scenes. This project establishes the shielding requirements that will ensure that the exposure of a user to ionizing radiation is below the U.S. Nuclear Regulatory Commission's allowable limits, and also develops the benchtop model for testing the system in a controlled environment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1997xrb..book.....L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1997xrb..book.....L"><span><span class="hlt">X-ray</span> Binaries</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lewin, Walter H. G.; van Paradijs, Jan; van den Heuvel, Edward Peter Jacobus</p> <p>1997-01-01</p> <p>Preface; 1. The properties of <span class="hlt">X-ray</span> binaries, N. E. White, F. Nagase and A. N. Parmar; 2. Optical and ultraviolet observations of <span class="hlt">X-ray</span> binaries J. van Paradijs and J. E. McClintock; 3. Black-hole binaries Y. Tanaka and W. H. G. Lewin; 4. <span class="hlt">X-ray</span> bursts Walter H. G. Lewin, Jan Van Paradijs and Ronald E. Taam; 5. Millisecond pulsars D. Bhattacharya; 6. Rapid aperiodic variability in binaries M. van der Klis; 7. Radio properties of <span class="hlt">X-ray</span> binaries R. M. Hjellming and X. Han; 8. Cataclysmic variable stars France Anne-Dominic Córdova; 9. Normal galaxies and their <span class="hlt">X-ray</span> binary populations G. Fabbiano; 10. Accretion in close binaries Andrew King; 11. Formation and evolution of neutron stars and black holes in binaries F. Verbunt and E. P. J. van den Heuvel; 12. The magnetic fields of neutron stars and their evolution D. Bhattacharya and G. Srinivasan; 13. Cosmic gamma-ray bursts K. Hurley; 14. A catalogue of <span class="hlt">X-ray</span> binaries Jan van Paradijs; 15. A compilation of cataclysmic binaries with known or suspected orbital periods Hans Ritter and Ulrich Kolb; References; Index.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20020066766','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20020066766"><span>Soft <span class="hlt">X-Ray</span> Emissions from Planets and Moons</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bhardwaj, A.; Gladstone, G. R.; Elsner, R. F.; Waite, J. H., Jr.; Grodent, D.; Cravens, T. E.; Howell, R. R.; Metzger, A. E.; Ostgaard, N.; Maurellis, A.; Six, N. Frank (Technical Monitor)</p> <p>2002-01-01</p> <p>A wide variety of solar system <span class="hlt">planetary</span> bodies are now known to radiate in the soft <span class="hlt">x-ray</span> energy (<5 keV) regime. These include planets (Earth, Jupiter, Venus, Saturn): bodies having thick atmosphere and with/without intrinsic magnetic field; <span class="hlt">planetary</span> satellites (Moon, Io, Europa, Ganymede): bodies with no/thin atmosphere; and comets and Io plasma torus: bodies having extended tenuous atmosphere. Several different mechanisms have been proposed to explain the generation of soft <span class="hlt">x-rays</span> from these objects. whereas in the hard <span class="hlt">x-ray</span> energy range (>10 keV) <span class="hlt">x-rays</span> mainly result from electron bremsstrahlung process. In this paper we present a brief review of the <span class="hlt">x-ray</span> observations on each of the <span class="hlt">planetary</span> bodies and discuss their characteristics and proposed source mechanisms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.P21C1680T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.P21C1680T"><span>Phase relation of C-Mg-Fe-Si-O system under various oxygen fugacity conditions by in situ <span class="hlt">X-ray</span> diffraction experiments: Implication for <span class="hlt">planetary</span> interior</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Takahashi, S.; Ohtani, E.; Terasaki, H.; Ito, Y.; Funakoshi, K.; Higo, Y.</p> <p>2011-12-01</p> <p>Carbon is one of the major volatile elements and very important in the Earth, primitive meteorites and some achondrites, such as ureilites. The abundance of carbon has been estimated to be 100 times higher than that in the CI chondrite, in some of the stars with exoplanets, such as the circumstellar gas around Beta Pictoris (Roberge et al., 2006). In such a gas, carbon-enriched planets, "carbon-planet", may be formed. Carbon-planet interior is likely to be composed mainly of Carbon-bearing phase, such as carbide, carbonate, graphite and diamond. Therefore, it is important to investigate phase relations of carbon-rich systems under high pressure conditions. In this study, C-enriched Mg-Si-Fe-O system was investigated at high pressure and temperature in order to understand the internal structure of the carbon-planets. Phase relations were studied based on 2 series of experiments; (I) textural observation and chemical analysis of the sample recovered from high pressure and temperature and (II) in situ <span class="hlt">X-ray</span> diffraction experiments. We used several different mineral assemblages for the starting materials, as shown below: (i) (Mg1.8,Fe0.2)SiO4 + Fe + SiO2 + C, (ii) (Mg1.8,Fe0.2)SiO4 + Fe + Si + C, (iii) MgO + Fe + SiO2 + C, (iv) MgO + Fe + Si + C. Oxygen fugacity (fO2) of the sample varies depending on these assembleges due to different O amounts in the starting materials. Chemical analyses of the recovered samples were performed using an electron microprobe. In situ <span class="hlt">X-ray</span> diffraction experiments were conducted at 4 and 15 GPa, and up to 1873 K at BL04B1 beamline, SPring-8 synchrotron facility. Different mineral assemblages were observed depending on the redox condition of the sample. The compositions of metallic melts changes from Fe-C compositions in oxidizing conditions to Fe-Si compositions in the reducing conditions. Based on in situ <span class="hlt">X-ray</span> diffraction experiments at 4 GPa, FeSi and SiC peaks appeared at 1373 K in the most reducing sample (iv), whereas Fe3C appeared</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014SPIE.9144E..1FH','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014SPIE.9144E..1FH"><span>Miniature lightweight <span class="hlt">x-ray</span> optics (MiXO) for solar system exploration</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hong, J.; Romaine, S.</p> <p>2014-07-01</p> <p>Over the last few decades, grazing incidence <span class="hlt">X-ray</span> optics have been a pivotal tool for advances in <span class="hlt">X-ray</span> astronomy. They have been successfully employed in many great observatories such as ROSAT, Chandra <span class="hlt">X-ray</span> Observatory and XMM-Newton. In <span class="hlt">planetary</span> science, <span class="hlt">X-ray</span> observations of Solar system objects are a great tool to understand the nature of the target bodies and the evolutionary history of the Solar system as a whole. To date, <span class="hlt">X-ray</span> observations in near-target <span class="hlt">planetary</span> missions have been limited to collimator-based instruments due to tight mass and volume constraints, arising from the multi-instrument nature of <span class="hlt">planetary</span> missions. In addition, unlike observations of astrophysical sources at virtually infinite distances, near-target observations of <span class="hlt">planetary</span> bodies introduce a unique set of challenges. While true focusing <span class="hlt">X-ray</span> optics can overcome these challenges, a practical implementation of focusing <span class="hlt">X-ray</span> optics for <span class="hlt">planetary</span> missions depends on the feasibility of compact lightweight <span class="hlt">X-ray</span> optics. We review scientific motivations for <span class="hlt">X-ray</span> observations of <span class="hlt">planetary</span> bodies and illustrate the unique challenges encountered in <span class="hlt">planetary</span> missions through a few examples. We introduce a new metal-ceramic hybrid technology for <span class="hlt">X-ray</span> mirrors that can enable compact lightweight Wolter-I <span class="hlt">X-ray</span> optics suitable for resource limited <span class="hlt">planetary</span> missions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19790050747&hterms=butts&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dbutts','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19790050747&hterms=butts&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dbutts"><span><span class="hlt">Future</span> <span class="hlt">planetary</span> probes for Jupiter and Saturn</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Butts, A. J.; Murphy, J. P.</p> <p>1979-01-01</p> <p>The paper describes a study conducted to identify the technology developments that would allow deep atmospheric investigations of Jupiter and Saturn to proceed beyond currently planned investigation of the upper atmosphere. The study considered a deep probe mission that would provide the capability to scientifically examine <span class="hlt">planetary</span> atmospheres to the 1000-bar level and 1400-K level. The major conclusions of the study are that (1) a probe designed for Jupiter can be used with minor changes for Saturn, (2) new science instrument technology developments are required, and (3) the only new technology developments required in the engineering subsystem are high pressure thermal insulation materials and advanced data processing techniques.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhRvL.113o3002S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhRvL.113o3002S"><span>Reabsorption of Soft <span class="hlt">X-Ray</span> Emission at High <span class="hlt">X-Ray</span> Free-Electron Laser Fluences</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schreck, Simon; Beye, Martin; Sellberg, Jonas A.; McQueen, Trevor; Laksmono, Hartawan; Kennedy, Brian; Eckert, Sebastian; Schlesinger, Daniel; Nordlund, Dennis; Ogasawara, Hirohito; Sierra, Raymond G.; Segtnan, Vegard H.; Kubicek, Katharina; Schlotter, William F.; Dakovski, Georgi L.; Moeller, Stefan P.; Bergmann, Uwe; Techert, Simone; Pettersson, Lars G. M.; Wernet, Philippe; Bogan, Michael J.; Harada, Yoshihisa; Nilsson, Anders; Föhlisch, Alexander</p> <p>2014-10-01</p> <p>We report on oxygen K-edge soft <span class="hlt">x-ray</span> emission spectroscopy from a liquid water jet at the Linac Coherent Light Source. We observe significant changes in the spectral content when tuning over a wide range of incident <span class="hlt">x-ray</span> fluences. In addition the total emission yield decreases at high fluences. These modifications result from reabsorption of <span class="hlt">x-ray</span> emission by valence-excited molecules generated by the Auger cascade. Our observations have major implications for <span class="hlt">future</span> <span class="hlt">x-ray</span> emission studies at intense <span class="hlt">x-ray</span> sources. We highlight the importance of the <span class="hlt">x-ray</span> pulse length with respect to the core-hole lifetime.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25375708','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25375708"><span>Reabsorption of soft <span class="hlt">x-ray</span> emission at high <span class="hlt">x-ray</span> free-electron laser fluences.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Schreck, Simon; Beye, Martin; Sellberg, Jonas A; McQueen, Trevor; Laksmono, Hartawan; Kennedy, Brian; Eckert, Sebastian; Schlesinger, Daniel; Nordlund, Dennis; Ogasawara, Hirohito; Sierra, Raymond G; Segtnan, Vegard H; Kubicek, Katharina; Schlotter, William F; Dakovski, Georgi L; Moeller, Stefan P; Bergmann, Uwe; Techert, Simone; Pettersson, Lars G M; Wernet, Philippe; Bogan, Michael J; Harada, Yoshihisa; Nilsson, Anders; Föhlisch, Alexander</p> <p>2014-10-10</p> <p>We report on oxygen K-edge soft <span class="hlt">x-ray</span> emission spectroscopy from a liquid water jet at the Linac Coherent Light Source. We observe significant changes in the spectral content when tuning over a wide range of incident <span class="hlt">x-ray</span> fluences. In addition the total emission yield decreases at high fluences. These modifications result from reabsorption of <span class="hlt">x-ray</span> emission by valence-excited molecules generated by the Auger cascade. Our observations have major implications for <span class="hlt">future</span> <span class="hlt">x-ray</span> emission studies at intense <span class="hlt">x-ray</span> sources. We highlight the importance of the <span class="hlt">x-ray</span> pulse length with respect to the core-hole lifetime.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://images.nasa.gov/#/details-PIA18406.html','SCIGOVIMAGE-NASA'); return false;" href="https://images.nasa.gov/#/details-PIA18406.html"><span><span class="hlt">X-Ray</span> Instrument for Mars 2020 Rover is PIXL</span></a></p> <p><a target="_blank" href="https://images.nasa.gov/">NASA Image and Video Library</a></p> <p></p> <p>2014-07-31</p> <p>This diagram depicts the sensor head of the <span class="hlt">Planetary</span> Instrument for <span class="hlt">X-RAY</span> Lithochemistry, or PIXL, which has been selected as one of seven investigations for the payload of NASA Mars 2020 rover mission.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19820018210','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19820018210"><span>Hard <span class="hlt">X-ray</span> astrophysics</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rothschild, R. E.</p> <p>1981-01-01</p> <p>Past hard <span class="hlt">X-ray</span> and lower energy satellite instruments are reviewed and it is shown that observation above 20 keV and up to hundreds of keV can provide much valuable information on the astrophysics of cosmic sources. To calculate possible sensitivities of <span class="hlt">future</span> arrays, the efficiencies of a one-atmosphere inch gas counter (the HEAO-1 A-2 xenon filled HED3) and a 3 mm phoswich scintillator (the HEAO-1 A-4 Na1 LED1) were compared. Above 15 keV, the scintillator was more efficient. In a similar comparison, the sensitivity of germanium detectors did not differ much from that of the scintillators, except at high energies where the sensitivity would remain flat and not rise with loss of efficiency. Questions to be addressed concerning the physics of active galaxies and the diffuse radiation background, black holes, radio pulsars, <span class="hlt">X-ray</span> pulsars, and galactic clusters are examined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15903864','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15903864"><span>Clocking femtosecond <span class="hlt">X</span> <span class="hlt">rays</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cavalieri, A L; Fritz, D M; Lee, S H; Bucksbaum, P H; Reis, D A; Rudati, J; Mills, D M; Fuoss, P H; Stephenson, G B; Kao, C C; Siddons, D P; Lowney, D P; Macphee, A G; Weinstein, D; Falcone, R W; Pahl, R; Als-Nielsen, J; Blome, C; Düsterer, S; Ischebeck, R; Schlarb, H; Schulte-Schrepping, H; Tschentscher, Th; Schneider, J; Hignette, O; Sette, F; Sokolowski-Tinten, K; Chapman, H N; Lee, R W; Hansen, T N; Synnergren, O; Larsson, J; Techert, S; Sheppard, J; Wark, J S; Bergh, M; Caleman, C; Huldt, G; van der Spoel, D; Timneanu, N; Hajdu, J; Akre, R A; Bong, E; Emma, P; Krejcik, P; Arthur, J; Brennan, S; Gaffney, K J; Lindenberg, A M; Luening, K; Hastings, J B</p> <p>2005-03-25</p> <p>Linear-accelerator-based sources will revolutionize ultrafast <span class="hlt">x-ray</span> science due to their unprecedented brightness and short pulse duration. However, time-resolved studies at the resolution of the <span class="hlt">x-ray</span> pulse duration are hampered by the inability to precisely synchronize an external laser to the accelerator. At the Sub-Picosecond Pulse Source at the Stanford Linear-Accelerator Center we solved this problem by measuring the arrival time of each high energy electron bunch with electro-optic sampling. This measurement indirectly determined the arrival time of each <span class="hlt">x-ray</span> pulse relative to an external pump laser pulse with a time resolution of better than 60 fs rms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19940017993','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19940017993"><span>Detection of <span class="hlt">x</span> <span class="hlt">ray</span> sources in PROS</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Deponte, J.; Primini, F. A.</p> <p>1992-01-01</p> <p>The problem of detecting discrete sources in <span class="hlt">x-ray</span> images has much in common with the problem of automatic source detection at other wavelengths. In all cases, one searches for positive brightness enhancements exceeding a certain threshold, which appear consistent with what one expects for a point source, in the presence of a (possibly) spatially variable background. Multidimensional point spread functions (e.g., dependent on detector position and photon energy) are also common. At the same time, the problem in <span class="hlt">x-ray</span> astronomy has some unique aspects. For example, for typical <span class="hlt">x-ray</span> exposures in current or recent observatories, the number of available pixels far exceeds the number of actual <span class="hlt">x-ray</span> events, so Poisson, rather than Gaussian statistics apply. Further, extended cosmic <span class="hlt">x-ray</span> sources are common, and one often desires to detect point sources in the vicinity or even within bright, diffuse <span class="hlt">x-ray</span> emission. Finally, support structures in <span class="hlt">x-ray</span> detectors often cast sharp shadows in <span class="hlt">x-ray</span> images making it necessary to detect sources in a region of rapidly varying exposure. We have developed a source detection package within the IRAF/PROS environment which attempts to deal with some of the problems of <span class="hlt">x-ray</span> source detection. We have patterned our package after the successful Einstein Observatory <span class="hlt">x-ray</span> source detection programs. However, we have attempted to improve the flexibility and accessibility of the functions and to provide a graphical front-end for the user. Our philosophy has been to use standard IRAF tasks whenever possible for image manipulation and to separate general functions from mission-specific ones. We will report on the current status of the package and discuss <span class="hlt">future</span> developments, including simulation tasks, to allow the user to assess detection efficiency and source significance, tasks to determine source intensity, and alternative detection algorithms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20050167005','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20050167005"><span>Calculating the <span class="hlt">X-Ray</span> Fluorescence from the Planet Mercury Due to High-Energy Electrons</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Burbine, T. H.; Trombka, J. I.; Bergstrom, P. M., Jr.; Christon, S. P.</p> <p>2005-01-01</p> <p>The least-studied terrestrial planet is Mercury due to its proximity to the Sun, which makes telescopic observations and spacecraft encounters difficult. Our lack of knowledge about Mercury should change in the near <span class="hlt">future</span> due to the recent launching of MESSENGER, a Mercury orbiter. Another mission (BepiColombo) is currently being planned. The <span class="hlt">x-ray</span> spectrometer on MESSENGER (and planned for BepiColombo) can characterize the elemental composition of a <span class="hlt">planetary</span> surface by measuring emitted fluorescent <span class="hlt">x-rays</span>. If electrons are ejected from an atom s inner shell by interaction with energetic particles such as photons, electrons, or ions, electrons from an outer shell can transfer to the inner shell. Characteristic <span class="hlt">x-rays</span> are then emitted with energies that are the difference between the binding energy of the ion in its excited state and that of the ion in its ground state. Because each element has a unique set of energy levels, each element emits <span class="hlt">x-rays</span> at a unique set of energies. Electrons and ions usually do not have the needed flux at high energies to cause significant <span class="hlt">x-ray</span> fluorescence on most <span class="hlt">planetary</span> bodies. This is not the case for Mercury where high-energy particles were detected during the Mariner 10 flybys. Mercury has an intrinsic magnetic field that deflects the solar wind, resulting in a bow shock in the solar wind and a magnetospheric cavity. Electrons and ions accelerated in the magnetosphere tend to follow its magnetic field lines and can impact the surface on Mercury s dark side Modeling has been done to determine if <span class="hlt">x-ray</span> fluorescence resulting from the impact of high-energy electrons accelerated in Mercury's magnetosphere can be detected by MESSENGER. Our goal is to understand how much bulk chemical information can be obtained from <span class="hlt">x-ray</span> fluorescence measurements on the dark side of Mercury.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002AdSpR..30.1895M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002AdSpR..30.1895M"><span>SMART-1 technology preparation for <span class="hlt">future</span> <span class="hlt">planetary</span> missions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Marini, A. E.; Racca, G. D.; Foing, B. H.</p> <p></p> <p>SMART-1 is the first ESA Small Mission for Advanced Research in Technology, with the prime objective of demonstrating the use of Solar Electric Primary Propulsion in a <span class="hlt">planetary</span> mission. Further to this, SMART-1 will test novel spacecraft technologies and will host six instruments carrying out nine technology and science experiments, all aimed at preparing <span class="hlt">future</span> ESA Cornerstones, including the ESA Mercury Cornerstone (now named BepiColombo) and other <span class="hlt">future</span> <span class="hlt">planetary</span> missions under study, as well as solar and fundamental physics missions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010SSRv..157..167F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010SSRv..157..167F"><span><span class="hlt">X-ray</span> Reflection</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fabian, A. C.; Ross, R. R.</p> <p>2010-12-01</p> <p>Material irradiated by <span class="hlt">X-rays</span> produces backscattered radiation which is commonly known as the Reflection Spectrum. It consists of a structured continuum, due at high energies to the competition between photoelectric absorption and electron scattering enhanced at low energies by emission from the material itself, together with a complex line spectrum. We briefly review the history of <span class="hlt">X-ray</span> reflection in astronomy and discuss various methods for computing the reflection spectrum from cold and ionized gas, illustrated with results from our own work reflionx. We discuss how the reflection spectrum can be used to obtain the geometry of the accretion flow, particularly the inner regions around black holes and neutron stars.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19720015181&hterms=Acad&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DAcad','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19720015181&hterms=Acad&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DAcad"><span><span class="hlt">X-ray</span> fluorescence experiment</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Adler, I.; Trombka, J. I.; Gerard, J.; Schmadebeck, R.; Lowman, P.; Blodgett, H.; Yin, L.; Eller, E.; Lamothe, R.; Gorenstein, P.</p> <p>1972-01-01</p> <p>The preliminary results from the Sco X-1 and Cyg X-1 obtained from the Apollo 15 <span class="hlt">X-ray</span> detector data are presented along with preliminary results of the <span class="hlt">X-ray</span> fluorescence spectrometric data of the lunar surface composition. The production of the characteristic <span class="hlt">X-rays</span> following the interaction of solar <span class="hlt">X-rays</span> with the lunar surface is described along with the <span class="hlt">X-ray</span> spectrometer. Preliminary analyses of the astronomical <span class="hlt">X-ray</span> observation and the <span class="hlt">X-ray</span> fluorescence data are presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JInst..10C4003M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JInst..10C4003M"><span>Novel active signal compression in low-noise analog readout at <span class="hlt">future</span> <span class="hlt">X-ray</span> FEL facilities</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Manghisoni, M.; Comotti, D.; Gaioni, L.; Lodola, L.; Ratti, L.; Re, V.; Traversi, G.; Vacchi, C.</p> <p>2015-04-01</p> <p>This work presents the design of a low-noise front-end implementing a novel active signal compression technique. This feature can be exploited in the design of analog readout channels for application to the next generation free electron laser (FEL) experiments. The readout architecture includes the low-noise charge sensitive amplifier (CSA) with dynamic signal compression, a time variant shaper used to process the signal at the preamplifier output and a 10-bit successive approximation register (SAR) analog-to-digital converter (ADC). The channel will be operated in such a way to cope with the high frame rate (exceeding 1 MHz) foreseen for <span class="hlt">future</span> XFEL machines. The choice of a 65 nm CMOS technology has been made in order to include all the building blocks in the target pixel pitch of 100 μm. This work has been carried out in the frame of the PixFEL Project funded by the Istituto Nazionale di Fisica Nucleare (INFN), Italy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/6853203','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/biblio/6853203"><span><span class="hlt">X-ray</span> beam finder</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Gilbert, H.W.</p> <p>1983-06-16</p> <p>An <span class="hlt">X-ray</span> beam finder for locating a focal spot of an <span class="hlt">X-ray</span> tube includes a mass of <span class="hlt">X-ray</span> opaque material having first and second axially-aligned, parallel-opposed faces connected by a plurality of substantially identical parallel holes perpendicular to the faces and a film holder for holding <span class="hlt">X-ray</span> sensitive film tightly against one face while the other face is placed in contact with the window of an <span class="hlt">X-ray</span> head.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://medlineplus.gov/ency/article/003805.htm','NIH-MEDLINEPLUS'); return false;" href="https://medlineplus.gov/ency/article/003805.htm"><span>Neck <span class="hlt">x-ray</span></span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... look at cervical vertebrae. These are the 7 bones of the spine in the neck. ... A neck <span class="hlt">x-ray</span> can detect: Bone joint that is out of position (dislocation) Breathing in a foreign object Broken bone (fracture) Disk problems (disks ...</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_12 --> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://medlineplus.gov/ency/article/003461.htm','NIH-MEDLINEPLUS'); return false;" href="https://medlineplus.gov/ency/article/003461.htm"><span>Extremity <span class="hlt">x-ray</span></span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... this test if you have signs of: A fracture Tumor Arthritis (inflammation of the joints) Normal Results The <span class="hlt">x-ray</span> shows normal structures for the age of the person. What Abnormal Results Mean ... bone (fracture) Dislocated bone Osteomyelitis (infection) Arthritis Other conditions for ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1991moff.work....7D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1991moff.work....7D"><span><span class="hlt">Planetary</span> protection issues and <span class="hlt">future</span> Mars missions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Devincenzi, D. L.; Klein, H. P.; Bagby, J. R.</p> <p>1991-12-01</p> <p>A primary scientific theme for the Space Exploration Initiative (SEI) is the search for life, extant or extinct, on Mars. Because of this, concerns have arisen about <span class="hlt">Planetary</span> Protection (PP), the prevention of biological cross-contamination between Earth and other planets during solar system exploration missions. A recent workshop assessed the necessity for, and impact of, PP requirements on the unmanned and human missions to Mars comprising the SEI. The following ground-rules were adopted: (1) Information needed for assessing PP issues must be obtained during the unmanned precursor mission phase prior to human landings. (2) Returned Mars samples will be considered biologically hazardous until proven otherwise. (3) Deposition of microbes on Mars and exposure of the crew to martian materials are inevitable when humans land. And (4) Human landings are unlikely until it is demonstrated that there is no harmful effect of martian materials on terrestrial life forms. These ground-rules dictated the development of a conservative PP strategy for precursor missions. Key features of the proposed strategy include: to prevent forward-contamination, all orbiters will follow Mars Observer PP procedures for assembly, trajectory, and lifetime. All landers will follow Viking PP procedures for assembly, microbial load reduction, and bio-shield. And, to prevent back-contamination, all sample return missions will have PP requirements which include fail-safe sample sealing, breaking contact chain with the martian surface, and containment and quarantine analysis in Earth-based laboratory. In addition to deliberating on scientific and technical issues, the workshop made several recommendations for dealing with forward and back-contamination concerns from non-scicntific perspectives.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19940029027','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19940029027"><span><span class="hlt">Planetary</span> protection issues and <span class="hlt">future</span> Mars missions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Devincenzi, D. L.; Klein, H. P.; Bagby, J. R.</p> <p>1991-01-01</p> <p>A primary scientific theme for the Space Exploration Initiative (SEI) is the search for life, extant or extinct, on Mars. Because of this, concerns have arisen about <span class="hlt">Planetary</span> Protection (PP), the prevention of biological cross-contamination between Earth and other planets during solar system exploration missions. A recent workshop assessed the necessity for, and impact of, PP requirements on the unmanned and human missions to Mars comprising the SEI. The following ground-rules were adopted: (1) Information needed for assessing PP issues must be obtained during the unmanned precursor mission phase prior to human landings. (2) Returned Mars samples will be considered biologically hazardous until proven otherwise. (3) Deposition of microbes on Mars and exposure of the crew to martian materials are inevitable when humans land. And (4) Human landings are unlikely until it is demonstrated that there is no harmful effect of martian materials on terrestrial life forms. These ground-rules dictated the development of a conservative PP strategy for precursor missions. Key features of the proposed strategy include: to prevent forward-contamination, all orbiters will follow Mars Observer PP procedures for assembly, trajectory, and lifetime. All landers will follow Viking PP procedures for assembly, microbial load reduction, and bio-shield. And, to prevent back-contamination, all sample return missions will have PP requirements which include fail-safe sample sealing, breaking contact chain with the martian surface, and containment and quarantine analysis in Earth-based laboratory. In addition to deliberating on scientific and technical issues, the workshop made several recommendations for dealing with forward and back-contamination concerns from non-scicntific perspectives.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011SPIE.8147E..1QO','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011SPIE.8147E..1QO"><span>Toward active <span class="hlt">x-ray</span> telescopes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>O'Dell, Stephen L.; Atkins, Carolyn; Button, Timothy W.; Cotroneo, Vincenzo; Davis, William N.; Doel, Peter; Feldman, Charlotte H.; Freeman, Mark D.; Gubarev, Mikhail V.; Kolodziejczak, Jeffery J.; Michette, Alan G.; Ramsey, Brian D.; Reid, Paul B.; Rodriguez Sanmartin, Daniel; Saha, Timo T.; Schwartz, Daniel A.; Trolier-McKinstry, Susan; Wilke, Rudeger H. T.; Willingale, Richard; Zhang, William W.</p> <p>2011-09-01</p> <p><span class="hlt">Future</span> <span class="hlt">x-ray</span> observatories will require high-resolution (< 1") optics with very-large-aperture (> 25 m2) areas. Even with the next generation of heavy-lift launch vehicles, launch-mass constraints and aperture-area requirements will limit the areal density of the grazing-incidence mirrors to about 1 kg/m2 or less. Achieving sub-arcsecond <span class="hlt">x-ray</span> imaging with such lightweight mirrors will require excellent mirror surfaces, precise and stable alignment, and exceptional stiffness or deformation compensation. Attaining and maintaining alignment and figure control will likely involve active (in-space adjustable) <span class="hlt">x-ray</span> optics. In contrast with infrared and visible astronomy, active optics for <span class="hlt">x-ray</span> astronomy is in its infancy. In the middle of the past decade, two efforts began to advance technologies for adaptive <span class="hlt">x-ray</span> telescopes: The Smart <span class="hlt">X-ray</span> Optics (SXO) Basic Technology project in the United Kingdom (UK) and the Generation-X (Gen-X) concept studies in the United States (US). This paper discusses relevant technological issues and summarizes progress toward active <span class="hlt">x-ray</span> telescopes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110015833','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110015833"><span>Toward Adaptive <span class="hlt">X-Ray</span> Telescopes</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>O'Dell, Stephen L.; Atkins, Carolyn; Button, Tim W.; Cotroneo, Vincenzo; Davis, William N.; Doel, Peer; Feldman, Charlotte H.; Freeman, Mark D.; Gubarev, Mikhail V.; Kolodziejczak, Jeffrey J.; Michette, Alan G.; Ramsey, Brian D.; Reid, Paul B.; Rodriguez Sanmartin, Daniel; Saha, Timo T.; Schwartz, Daniel A.; Trolier-McKinstry, Susan; Wilke, Rudeger H. T.; Willingale, Richard; Zhang, William W.</p> <p>2011-01-01</p> <p><span class="hlt">Future</span> <span class="hlt">x-ray</span> observatories will require high-resolution (less than 1 inch) optics with very-large-aperture (greater than 25 square meter) areas. Even with the next generation of heavy-lift launch vehicles, launch-mass constraints and aperture-area requirements will limit the surface areal density of the grazing-incidence mirrors to about 1 kilogram per square meter or less. Achieving sub-arcsecond <span class="hlt">x-ray</span> imaging with such lightweight mirrors will require excellent mirror surfaces, precise and stable alignment, and exceptional stiffness or deformation compensation. Attaining and maintaining alignment and figure control will likely involve adaptive (in-space adjustable) <span class="hlt">x-ray</span> optics. In contrast with infrared and visible astronomy, adaptive optics for <span class="hlt">x-ray</span> astronomy is in its infancy. In the middle of the past decade, two efforts began to advance technologies for adaptive <span class="hlt">x-ray</span> telescopes: The Generation-X (Gen-X) concept studies in the United States, and the Smart <span class="hlt">X-ray</span> Optics (SXO) Basic Technology project in the United Kingdom. This paper discusses relevant technological issues and summarizes progress toward adaptive <span class="hlt">x-ray</span> telescopes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120015758','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120015758"><span>Toward Active <span class="hlt">X-ray</span> Telescopes II</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>O'Dell, Stephen L.; Aldroft, Thomas L.; Atkins, Carolyn; Button, Timothy W.; Cotroneo, Vincenzo; Davis, William N.; Doel, Peter; Feldman, Charlotte H.; Freeman, Mark D.; Gubarev, Mikhail V.; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20120015758'); toggleEditAbsImage('author_20120015758_show'); toggleEditAbsImage('author_20120015758_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20120015758_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20120015758_hide"></p> <p>2012-01-01</p> <p>In the half century since the initial discovery of an astronomical (non-solar) <span class="hlt">x-ray</span> source, the sensitivity for detection of cosmic <span class="hlt">x-ray</span> sources has improved by ten orders of magnitude. Largely responsible for this dramatic progress has been the refinement of the (grazing-incidence) focusing <span class="hlt">x-ray</span> telescope. The <span class="hlt">future</span> of <span class="hlt">x-ray</span> astronomy relies upon the development of <span class="hlt">x-ray</span> telescopes with larger aperture areas (greater than 1 m2) and finer angular resolution (less than 1.). Combined with the special requirements of grazing-incidence optics, the mass and envelope constraints of space-borne telescopes render such advances technologically challenging.requiring precision fabrication, alignment, and assembly of large areas (greater than 100 m2) of lightweight (approximately 1 kg m2 areal density) mirrors. Achieving precise and stable alignment and figure control may entail active (in-space adjustable) <span class="hlt">x-ray</span> optics. This paper discusses relevant programmatic and technological issues and summarizes progress toward active <span class="hlt">x-ray</span> telescopes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20080044827&hterms=simbol&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dsimbol','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20080044827&hterms=simbol&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dsimbol"><span>Galaxies in the <span class="hlt">X-ray</span> Band</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hornschemeier, Ann</p> <p>2008-01-01</p> <p>This talk will provide a brief review of progress on <span class="hlt">X-ray</span> emission from normal (non-AGN) galaxy populations, including important constraints on the evolution of accreting binary populations over important cosmological timescales. We will also look to the <span class="hlt">future</span>, anticipating constraints from near-term imaging hard <span class="hlt">X-ray</span> missions such as NuSTAR, Simbol-X and NeXT and then the longer-term prospects for studying galaxies with the Generation-X mission.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20080037790&hterms=simbol&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dsimbol','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20080037790&hterms=simbol&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dsimbol"><span>Galaxies in the <span class="hlt">X-Ray</span> Band</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hornschemeier, Ann</p> <p>2008-01-01</p> <p>This talk will provide a brief review of progress an <span class="hlt">X-ray</span> emission from normal (non-AGN) galaxy populations, including important constraints on the evolution of accreting binary populations over important cosmological timescales. We will also look to the <span class="hlt">future</span>, anticipating constraints from near-term imaging hard <span class="hlt">X-ray</span> missions such as NuSTAR, Simbol-X and NeXT and then the longer-term prospects for studying galaxies with the Generation-X mission,</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2867759','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2867759"><span>The high energy <span class="hlt">X-ray</span> universe</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Giacconi, Riccardo</p> <p>2010-01-01</p> <p>Since its beginning in the early 1960s, the field of <span class="hlt">X-ray</span> astronomy has exploded, experiencing a ten-billion-fold increase in sensitivity, which brought it on par with the most advanced facilities at all wavelengths. I will briefly describe the revolutionary first discoveries prior to the launch of the Chandra and XMM-Newton <span class="hlt">X-ray</span> observatories, present some of the current achievements, and offer some thoughts about the <span class="hlt">future</span> of this field. PMID:20404148</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20170001387','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20170001387"><span>Obtaining and Using <span class="hlt">Planetary</span> Spatial Data into the <span class="hlt">Future</span>: The Role of the Mapping and <span class="hlt">Planetary</span> Spatial Infrastructure Team (MAPSIT)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Radebaugh, J.; Thomson, B. J.; Archinal, B.; Hagerty, J.; Gaddis, L.; Lawrence, S. J.; Sutton, S.</p> <p>2017-01-01</p> <p><span class="hlt">Planetary</span> spatial data, which include any remote sensing data or derived products with sufficient positional information such that they can be projected onto a <span class="hlt">planetary</span> body, continue to rapidly increase in volume and complexity. These data are the hard-earned fruits of decades of <span class="hlt">planetary</span> exploration, and are the end result of mission planning and execution. Maintaining these data using accessible formats and standards for all scientists has been necessary for the success of past, present, and <span class="hlt">future</span> <span class="hlt">planetary</span> missions. The Mapping and <span class="hlt">Planetary</span> Spatial Infrastructure Team (MAPSIT) is a group of <span class="hlt">planetary</span> community members tasked by NASA Headquarters to work with the <span class="hlt">planetary</span> science community to identify and prioritize their <span class="hlt">planetary</span> spatial data needs to help determine the best pathways for new data acquisition, usable product derivation, and tools/capability development that supports NASA's <span class="hlt">planetary</span> science missions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017LPICo1989.8051B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017LPICo1989.8051B"><span>Technology Planning for NASA's <span class="hlt">Future</span> <span class="hlt">Planetary</span> Science Missions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Beauchamp, P. M.; Cutts, J. A.; Mercer, C.; Dudzinski, L. A.</p> <p>2017-02-01</p> <p>As we look far into the <span class="hlt">future</span> and imagine what we might be doing in <span class="hlt">planetary</span> science in 2050 and beyond, we must also develop an iterative, dynamic technology planning process that fulfills our goals and is flexible enough to accommodate changes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMMR24A..08D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMMR24A..08D"><span>Multi-scale 3D <span class="hlt">X-ray</span> Imaging Capabilities at the Advanced Photon Source - Current status and <span class="hlt">future</span> direction (Invited)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>DeCarlo, F.; Xiao, X.; Khan, F.; Glowacki, A.; Schwarz, N.; Jacobsen, C.</p> <p>2011-12-01</p> <p>In <span class="hlt">x-ray</span> computed μ-tomography (μ-XCT), a thin scintillator screen is coupled to a visible light lens and camera system to obtain micrometer-scale transmission imaging of specimens as large as a few millimeters. Recent advances in detector technology allow collecting these images at unprecedented frame rates. For a high <span class="hlt">x-ray</span> flux density synchrotron facility like the Advanced Photon Source (APS), the detector exposure time ranges from hundreds of milliseconds to hundreds of picoseconds, making possible to acquire a full 3D micrometer-resolution dataset in less than one second. The micron resolution limitation of parallel <span class="hlt">x-ray</span> beam projection systems can be overcame by Transmission <span class="hlt">X-ray</span> Microscopes (TXM) where part of the image magnification is done in <span class="hlt">x-ray</span> regime using <span class="hlt">x-ray</span> optics like capillary condensers and Fresnel zone plates. These systems, when installed on a synchrotron <span class="hlt">x-ray</span> source, can generate 2D images with up to 20 nm resolution with second exposure time and collect a full 3D nano-resolution dataset in few minutes. μ-XCT and TXM systems available at the <span class="hlt">x-ray</span> imaging beamlines of the APS are routinely used in material science and geoscience applications where high-resolution and fast 3D imaging are instrumental in extracting in situ four-dimensional dynamic information. In this presentation we describe the computational challenges associated with μ-XCT and TXM systems and present the framework and infrastructure developed at the APS to allow for routine multi-scale data integration between the two systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMMR24A..08D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMMR24A..08D"><span>Multi-scale 3D <span class="hlt">X-ray</span> Imaging Capabilities at the Advanced Photon Source - Current status and <span class="hlt">future</span> direction (Invited)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>DeCarlo, F.; Xiao, X.; Khan, F.; Glowacki, A.; Schwarz, N.; Jacobsen, C.</p> <p>2013-12-01</p> <p>In <span class="hlt">x-ray</span> computed μ-tomography (μ-XCT), a thin scintillator screen is coupled to a visible light lens and camera system to obtain micrometer-scale transmission imaging of specimens as large as a few millimeters. Recent advances in detector technology allow collecting these images at unprecedented frame rates. For a high <span class="hlt">x-ray</span> flux density synchrotron facility like the Advanced Photon Source (APS), the detector exposure time ranges from hundreds of milliseconds to hundreds of picoseconds, making possible to acquire a full 3D micrometer-resolution dataset in less than one second. The micron resolution limitation of parallel <span class="hlt">x-ray</span> beam projection systems can be overcame by Transmission <span class="hlt">X-ray</span> Microscopes (TXM) where part of the image magnification is done in <span class="hlt">x-ray</span> regime using <span class="hlt">x-ray</span> optics like capillary condensers and Fresnel zone plates. These systems, when installed on a synchrotron <span class="hlt">x-ray</span> source, can generate 2D images with up to 20 nm resolution with second exposure time and collect a full 3D nano-resolution dataset in few minutes. μ-XCT and TXM systems available at the <span class="hlt">x-ray</span> imaging beamlines of the APS are routinely used in material science and geoscience applications where high-resolution and fast 3D imaging are instrumental in extracting in situ four-dimensional dynamic information. In this presentation we describe the computational challenges associated with μ-XCT and TXM systems and present the framework and infrastructure developed at the APS to allow for routine multi-scale data integration between the two systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005sfet.confE..49E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005sfet.confE..49E"><span>Investigation of Diffuse <span class="hlt">X-ray</span> Emission in the Massive Star Forming Region NGC 6334 with Chandra and <span class="hlt">Future</span> Prospects with Astro-E2</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ezoe, Yuichiro; Kokubun, Motohide; Makishima, Kazuo</p> <p>2005-07-01</p> <p>Recent studies with Chandra have been revealing that there are various diffuse <span class="hlt">X-ray</span> emission originated from 106-7 K plasma or possible accelerated particles in massive star forming regions (e.g., Wolk et al. 2002, Townsley et al. 2003). We analyzed Chandra data of the representative massive star-forming region NGC 6334 where hard <span class="hlt">X-ray</span> emission have been detected with ASCA (Sekimoto et al. 2000). In addition to 800 point sources, we found diffuse <span class="hlt">X-ray</span> emission (5x9 pc and 2e33 erg/s in the 0.5-8 keV luminosity). It shows positionally different spectra; thermal plasma emission of several keV in low absorption regions, while flat continua in dense cloud cores. The former emission can be explained by hot plasma heated at strong shocks of fast stellar-winds from young OB stars, while the latter by accelerated particles at the shock. We then roughly estimated possible contribution of diffuse <span class="hlt">X-ray</span> emission in Galactic massive star forming regions to the puzzling Galactic Ridge <span class="hlt">X-ray</span> emission (e.g., Kaneda et al. 1997) as ˜10% in luminosity. Related to this issue, we show potential importance of simultaneous observation with Chandra and, the Japanese new <span class="hlt">X-ray</span> observatory, Astro-E2.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AAS...22941505V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AAS...22941505V"><span>The Past, Present, and <span class="hlt">Future</span> of <span class="hlt">Planetary</span> Systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vanderburg, Andrew</p> <p>2017-01-01</p> <p>We are searching for planets using the Kepler spacecraft in its extended K2 mission. K2 data processing is more challenging than Kepler, but new techniques have permitted the discovery of hundreds of planet candidates. Our discoveries are yielding intriguing insights about the past, present, and <span class="hlt">future</span> of <span class="hlt">planetary</span> systems -- that is, the history of how planets might form and migrate, their present-day characteristics, and the ultimate fate of <span class="hlt">planetary</span> systems. I will discuss what we have learned, in particular from the discovery of a hot Jupiter with close <span class="hlt">planetary</span> companions, planets orbiting nearby bright stars, and a disintegrating minor planet transiting a white dwarf. This work was supported by the National Science Foundation Graduate Research Fellowship Program.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20080045804','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20080045804"><span>5.8 <span class="hlt">X-ray</span> Calorimeters</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Porter, F. Scott</p> <p>2008-01-01</p> <p><span class="hlt">X-ray</span> calorimeter instruments for astrophysics have seen rapid development since they were invented in 1984. The prime instrument on all currently planned <span class="hlt">X-ray</span> spectroscopic observatories is based on calorimeter technology. This relatively simple detection concept that senses the energy of an incident photon by measuring the temperature rise of an absorber material at very low temperatures, can form the basis of a very high performance, non-dispersive spectrometer. State-of-the-art calorimeter instruments have resolving powers of over 3000, large simultaneous band-passes, and near unit efficiency. This coupled with the intrinsic imaging capability of a pixilated <span class="hlt">x-ray</span> calorimeter array, allows true spectral-spatial instruments to be constructed. In this chapter I briefly review the detection scheme, the state-of-the-art in <span class="hlt">X-ray</span> calorimeter instruments and the <span class="hlt">future</span> outlook for this technology.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140010094','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140010094"><span>Optics Developments for <span class="hlt">X-Ray</span> Astronomy</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ramsey, Brian</p> <p>2014-01-01</p> <p><span class="hlt">X-ray</span> optics has revolutionized <span class="hlt">x-ray</span> astronomy. The degree of background suppression that these afford, have led to a tremendous increase in sensitivity. The current Chandra observatory has the same collecting area (approx. 10(exp 3)sq cm) as the non-imaging UHURU observatory, the first <span class="hlt">x-ray</span> observatory which launched in 1970, but has 5 orders of magnitude more sensitivity due to its focusing optics. In addition, its 0.5 arcsec angular resolution has revealed a wealth of structure in many cosmic <span class="hlt">x-ray</span> sources. The Chandra observatory achieved its resolution by using relatively thick pieces of Zerodur glass, which were meticulously figured and polished to form the four-shell nested array. The resulting optical assembly weighed around 1600 kg, and cost approximately $0.5B. The challenge for <span class="hlt">future</span> <span class="hlt">x-ray</span> astronomy missions is to greatly increase the collecting area (by one or more orders of magnitude) while maintaining high angular resolution, and all within realistic mass and budget constraints. A review of the current status of US optics for <span class="hlt">x-ray</span> astronomy will be provided along with the challenges for <span class="hlt">future</span> developments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JSWSC...6A..31P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JSWSC...6A..31P"><span><span class="hlt">Planetary</span> space weather: scientific aspects and <span class="hlt">future</span> perspectives</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Plainaki, Christina; Lilensten, Jean; Radioti, Aikaterini; Andriopoulou, Maria; Milillo, Anna; Nordheim, Tom A.; Dandouras, Iannis; Coustenis, Athena; Grassi, Davide; Mangano, Valeria; Massetti, Stefano; Orsini, Stefano; Lucchetti, Alice</p> <p>2016-08-01</p> <p>In this paper, we review the scientific aspects of <span class="hlt">planetary</span> space weather at different regions of our Solar System, performing a comparative planetology analysis that includes a direct reference to the circum-terrestrial case. Through an interdisciplinary analysis of existing results based both on observational data and theoretical models, we review the nature of the interactions between the environment of a Solar System body other than the Earth and the impinging plasma/radiation, and we offer some considerations related to the planning of <span class="hlt">future</span> space observations. We highlight the importance of such comparative studies for data interpretations in the context of <span class="hlt">future</span> space missions (e.g. ESA JUICE; ESA/JAXA BEPI COLOMBO). Moreover, we discuss how the study of <span class="hlt">planetary</span> space weather can provide feedback for better understanding the traditional circum-terrestrial space weather. Finally, a strategy for <span class="hlt">future</span> global investigations related to this thematic is proposed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21064151','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21064151"><span><span class="hlt">X-ray</span> lasers: from the fundamentals to the applications</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kawachi, Tetsuya</p> <p>2007-07-11</p> <p>This paper gives an overview of recent progress of laser-driven plasma <span class="hlt">x-ray</span> lasers. For the recombining plasma lasers, the mechanism of generating the population inversion is explained, and the difficulties which we face are pointed out. In the collisional-excitation lasers, substantial reduction of the pumping energy is successfully achieved for the wavelength up to 12 nm, and the <span class="hlt">x-ray</span> lasers are applied to wide variety of research fields such as material science, plasma diagnostics, atomic physics and <span class="hlt">x-ray</span> imaging. We also remark the <span class="hlt">future</span> perspective of the <span class="hlt">x-ray</span> lasers, especially for the shorter wavelength <span class="hlt">x-ray</span> lasers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20040081224&hterms=controlling+senses&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dcontrolling%2Bsenses','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20040081224&hterms=controlling+senses&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dcontrolling%2Bsenses"><span><span class="hlt">X-ray</span> Spectrometer</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Porter, F. Scott</p> <p>2004-01-01</p> <p>The <span class="hlt">X-ray</span> Spectrometer (XRS) instrument is a revolutionary non-dispersive spectrometer that will form the basis for the Astro-E2 observatory to be launched in 2005. We have recently installed a flight spare X R S microcalorimeter spectrometer at the EBIT-I facility at LLNL replacing the XRS from the earlier Astro-E mission and providing twice the resolution. The X R S microcalorimeter is an <span class="hlt">x-ray</span> detector that senses the heat deposited by the incident photon. It achieves a high energy resolution by operating at 0.06K and by carefully controlling the heat capacity and thermal conductance. The XRS/EBIT instrument has 32 pixels in a square geometry and achieves an energy resolution of 6 eV at 6 keV, with a bandpass from 0.1 to 12 keV (or more at higher operating temperature). The instrument allows detailed studies of the <span class="hlt">x-ray</span> line emission of laboratory plasmas. The XRS/EBIT also provides an extensive calibration "library" for the Astro-E2 observatory.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20040082346&hterms=electroless&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Delectroless','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20040082346&hterms=electroless&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Delectroless"><span><span class="hlt">X-Ray</span> Vision</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ramsey, B. D.; Elsner, R. F.; Engelhaupt, D.; Kolodziejczak, J. J.; ODell, S. L.; Speegle, C. O.; Weisskopf, M. C.</p> <p>2004-01-01</p> <p>We are fabricating optics for the hard-<span class="hlt">x-ray</span> region using electroless nickel replication. The attraction of this process, which has been widely used elsewhere, is that the resulting full shell optics are inherently stable and thus can have very good angular resolution. The challenge with this process is to develop lightweight optics (nickel has a relatively high density of 8.9 g/cu cm), and to keep down the costs of mandrel fabrication. We accomplished the former through the development of high-strength nickel alloys that permit very thin shells without fabrication- and handling-induced deformations. For the latter, we have utilized inexpensive grinding and diamond turning to figure the mandrels and then purpose-built polishing machines to finish the surface. In-house plating tanks and a simple water-bath separation system complete the process. To date we have built shells ranging in size from 5 cm diameter to 50 cm, and with thickness down to 100 micron. For our HERO balloon program, we are fabricating over 200 iridium-coated shells, 250 microns thick, for hard-<span class="hlt">x-ray</span> imaging up to 75 keV. Early test results on these have indicated half-power-diameters of 15 arcsec. The status of these and other hard-<span class="hlt">x-ray</span> optics will be reviewed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20040082346&hterms=electroless+nickel&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Delectroless%2Bnickel','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20040082346&hterms=electroless+nickel&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Delectroless%2Bnickel"><span><span class="hlt">X-Ray</span> Vision</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ramsey, B. D.; Elsner, R. F.; Engelhaupt, D.; Kolodziejczak, J. J.; ODell, S. L.; Speegle, C. O.; Weisskopf, M. C.</p> <p>2004-01-01</p> <p>We are fabricating optics for the hard-<span class="hlt">x-ray</span> region using electroless nickel replication. The attraction of this process, which has been widely used elsewhere, is that the resulting full shell optics are inherently stable and thus can have very good angular resolution. The challenge with this process is to develop lightweight optics (nickel has a relatively high density of 8.9 g/cu cm), and to keep down the costs of mandrel fabrication. We accomplished the former through the development of high-strength nickel alloys that permit very thin shells without fabrication- and handling-induced deformations. For the latter, we have utilized inexpensive grinding and diamond turning to figure the mandrels and then purpose-built polishing machines to finish the surface. In-house plating tanks and a simple water-bath separation system complete the process. To date we have built shells ranging in size from 5 cm diameter to 50 cm, and with thickness down to 100 micron. For our HERO balloon program, we are fabricating over 200 iridium-coated shells, 250 microns thick, for hard-<span class="hlt">x-ray</span> imaging up to 75 keV. Early test results on these have indicated half-power-diameters of 15 arcsec. The status of these and other hard-<span class="hlt">x-ray</span> optics will be reviewed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20040081224&hterms=x-ray+pixel+detector&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dx-ray%2Bpixel%2Bdetector','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20040081224&hterms=x-ray+pixel+detector&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dx-ray%2Bpixel%2Bdetector"><span><span class="hlt">X-ray</span> Spectrometer</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Porter, F. Scott</p> <p>2004-01-01</p> <p>The <span class="hlt">X-ray</span> Spectrometer (XRS) instrument is a revolutionary non-dispersive spectrometer that will form the basis for the Astro-E2 observatory to be launched in 2005. We have recently installed a flight spare X R S microcalorimeter spectrometer at the EBIT-I facility at LLNL replacing the XRS from the earlier Astro-E mission and providing twice the resolution. The X R S microcalorimeter is an <span class="hlt">x-ray</span> detector that senses the heat deposited by the incident photon. It achieves a high energy resolution by operating at 0.06K and by carefully controlling the heat capacity and thermal conductance. The XRS/EBIT instrument has 32 pixels in a square geometry and achieves an energy resolution of 6 eV at 6 keV, with a bandpass from 0.1 to 12 keV (or more at higher operating temperature). The instrument allows detailed studies of the <span class="hlt">x-ray</span> line emission of laboratory plasmas. The XRS/EBIT also provides an extensive calibration "library" for the Astro-E2 observatory.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20010094537','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20010094537"><span><span class="hlt">X-Ray</span> Astronomy</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wu, S. T.</p> <p>2000-01-01</p> <p>Dr. S. N. Zhang has lead a seven member group (Dr. Yuxin Feng, Mr. XuejunSun, Mr. Yongzhong Chen, Mr. Jun Lin, Mr. Yangsen Yao, and Ms. Xiaoling Zhang). This group has carried out the following activities: continued data analysis from space astrophysical missions CGRO, RXTE, ASCA and Chandra. Significant scientific results have been produced as results of their work. They discovered the three-layered accretion disk structure around black holes in <span class="hlt">X-ray</span> binaries; their paper on this discovery is to appear in the prestigious Science magazine. They have also developed a new method for energy spectral analysis of black hole <span class="hlt">X-ray</span> binaries; four papers on this topics were presented at the most recent Atlanta AAS meeting. They have also carried Monte-Carlo simulations of <span class="hlt">X-ray</span> detectors, in support to the hardware development efforts at Marshall Space Flight Center (MSFC). These computation-intensive simulations have been carried out entirely on the computers at UAH. They have also carried out extensive simulations for astrophysical applications, taking advantage of the Monte-Carlo simulation codes developed previously at MSFC and further improved at UAH for detector simulations. One refereed paper and one contribution to conference proceedings have been resulted from this effort.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20080004562','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20080004562"><span><span class="hlt">X-ray</span> lithography masking</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Smith, Henry I. (Inventor); Lim, Michael (Inventor); Carter, James (Inventor); Schattenburg, Mark (Inventor)</p> <p>1998-01-01</p> <p><span class="hlt">X-ray</span> masking apparatus includes a frame having a supporting rim surrounding an <span class="hlt">x-ray</span> transparent region, a thin membrane of hard inorganic <span class="hlt">x-ray</span> transparent material attached at its periphery to the supporting rim covering the <span class="hlt">x-ray</span> transparent region and a layer of <span class="hlt">x-ray</span> opaque material on the thin membrane inside the <span class="hlt">x-ray</span> transparent region arranged in a pattern to selectively transmit <span class="hlt">x-ray</span> energy entering the <span class="hlt">x-ray</span> transparent region through the membrane to a predetermined image plane separated from the layer by the thin membrane. A method of making the masking apparatus includes depositing back and front layers of hard inorganic <span class="hlt">x-ray</span> transparent material on front and back surfaces of a substrate, depositing back and front layers of reinforcing material on the back and front layers, respectively, of the hard inorganic <span class="hlt">x-ray</span> transparent material, removing the material including at least a portion of the substrate and the back layers of an inside region adjacent to the front layer of hard inorganic <span class="hlt">x-ray</span> transparent material, removing a portion of the front layer of reinforcing material opposite the inside region to expose the surface of the front layer of hard inorganic <span class="hlt">x-ray</span> transparent material separated from the inside region by the latter front layer, and depositing a layer of <span class="hlt">x-ray</span> opaque material on the surface of the latter front layer adjacent to the inside region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20000021209','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20000021209"><span>Monitoring <span class="hlt">X-Ray</span> Emission from <span class="hlt">X-Ray</span> Bursters</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kaaret, Philip</p> <p>1998-01-01</p> <p>The goal of this investigation was to use the All-Sky Monitor on the Rossi <span class="hlt">X-Ray</span> Timing Explorer (RXTE) in combination with the Burst and Transient Source Experiment on the Compton Gamma-Ray Observatory to simultaneously measure the <span class="hlt">x-ray</span> (2-12 keV) and hard <span class="hlt">x-ray</span> (20-100 keV) emission from <span class="hlt">x-ray</span> bursters. The investigation was successful. We made the first simultaneous measurement of hard and soft <span class="hlt">x-ray</span> emission and found a strong anticorrelation of hard and soft <span class="hlt">x-ray</span> emission from the <span class="hlt">X-Ray</span> Burster 4U 0614+091. The monitoring performed under this investigation was also important in triggering target of opportunity observations of <span class="hlt">x-ray</span> bursters made under the investigation hard <span class="hlt">x-ray</span> emission of <span class="hlt">x-ray</span> bursters approved for RXTE cycles 1 and 2. These observations lead to a number of papers on high-frequency quasi-periodic oscillations and on hard <span class="hlt">x-ray</span> emission from the <span class="hlt">x-ray</span> bursters 4U 0614+091 and 4U 1705-44.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.radiologyinfo.org/en/info.cfm?pg=panoramic-xray','NIH-MEDLINEPLUS'); return false;" href="http://www.radiologyinfo.org/en/info.cfm?pg=panoramic-xray"><span>Panoramic Dental <span class="hlt">X-Ray</span></span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... Physician Resources Professions Site Index A-Z Panoramic Dental <span class="hlt">X-ray</span> Panoramic dental <span class="hlt">x-ray</span> uses a ... Your e-mail address: Personal message (optional): Bees: Wax: Notice: RadiologyInfo respects your privacy. Information entered here ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/762159','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/762159"><span>Soft <span class="hlt">X-ray</span> Imaging</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Seely, John</p> <p>1999-05-20</p> <p>The contents of this report cover the following: (1) design of the soft <span class="hlt">x-ray</span> telescope; (2) fabrication and characterization of the soft <span class="hlt">x-ray</span> telescope; and (3) experimental implementation at the OMEGA laser facility.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1060726','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1060726"><span>Fluctuation <span class="hlt">X-Ray</span> Scattering</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Saldin, PI: D. K.; Co-I's: J. C. H. Spence and P. Fromme</p> <p>2013-01-25</p> <p>The work supported by the grant was aimed at developing novel methods of finding the structures of biomolecules using <span class="hlt">x-rays</span> from novel sources such as the <span class="hlt">x-ray</span> free electron laser and modern synchrotrons</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19870000388&hterms=Bradley+James&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DBradley%252C%2BJames','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19870000388&hterms=Bradley+James&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DBradley%252C%2BJames"><span>Encapsulating <span class="hlt">X-Ray</span> Detectors</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Conley, Joseph M.; Bradley, James G.</p> <p>1987-01-01</p> <p>Vapor-deposited polymer shields crystals from environment while allowing <span class="hlt">X</span> <span class="hlt">rays</span> to pass. Polymer coating transparental to <span class="hlt">X</span> <span class="hlt">rays</span> applied to mercuric iodide detector in partial vacuum. Coating protects crystal from sublimation, chemical attack, and electrical degradation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AmJPh..80..621A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AmJPh..80..621A"><span>Dual <span class="hlt">X-ray</span> absorptiometry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Altman, Albert; Aaron, Ronald</p> <p>2012-07-01</p> <p>Dual <span class="hlt">X-ray</span> absorptiometry is widely used in analyzing body composition and imaging. Both the method and its limitations are related to the Compton and photoelectric contributions to the <span class="hlt">X-ray</span> attenuation coefficients of materials.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20080040774','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20080040774"><span>Eta Carinae: <span class="hlt">X-ray</span> Line Variations during the 2003 <span class="hlt">X-ray</span> Minimum, and the Orbit Orientation</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Corcoran, M. F.; Henley, D.; Hamaguchi, K.; Khibashi, K.; Pittard, J. M.; Stevens, I. R.; Gull, T. R.</p> <p>2007-01-01</p> <p>The <span class="hlt">future</span> evolution of Eta Carinae will be as a supernova (or hypernova) and black hole. The evolution is highly contingent on mass and angular momentum changes and instabilities. The presence of a companion can serve to trigger instabilities and provide pathways for mass and angular momentum exchange loss. <span class="hlt">X-rays</span> can be used a a key diagnostic tool: <span class="hlt">x-ray</span> temperatures trace pre-shock wind velocities, periodic <span class="hlt">x-ray</span> variability traces the orbit, and <span class="hlt">x-ray</span> line variations traces the flow and orientation of shocked gas. This brief presentation highlights <span class="hlt">x-ray</span> line variations from the HETG and presents a model of the colliding wind flow.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014apra.prop...95K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014apra.prop...95K"><span>Continued Development of Small-Pixel CZT and CdTe Detectors for <span class="hlt">Future</span> High-Angular-Resolution Hard <span class="hlt">X-ray</span> Missions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Krawczynski, Henric</p> <p></p> <p>The Nuclear Spectroscopic Telescope Array (NuSTAR) Small Explorer Mission was launched in June 2012 and has demonstrated the technical feasibility and high scientific impact of hard <span class="hlt">X-ray</span> astronomy. We propose to continue our current R&D program to develop finely pixelated semiconductor detectors and the associated readout electronics for the focal plane of a NuSTAR follow-up mission. The detector-ASIC (Application Specific Integrated Circuit) package will be ideally matched to the new generation of low-cost, low-mass <span class="hlt">X-ray</span> mirrors which achieve an order of magnitude better angular resolution than the NuSTAR mirrors. As part of this program, the Washington University group will optimize the contacts of 2x2 cm^2 footprint Cadmium Zinc Telluride (CZT) and Cadmium Telluride (CdTe) detectors contacted with 100x116 hexagonal pixels at a next-neighbor pitch of 200 microns. The Brookhaven National Laboratory group will design, fabricate, and test the next generation of the HEXID ASIC matched to the new <span class="hlt">X-ray</span> mirrors and the detectors, providing a low-power 100x116 channel ASIC with extremely low readout noise (i.e. with a root mean square noise of 13 electrons). The detectors will be tested with radioactive sources and in the focal plane of high-angular-resolution <span class="hlt">X-ray</span> mirrors at the <span class="hlt">X-ray</span> beam facilities at the Goddard and Marshall Space Flight Centers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1810000C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1810000C"><span>Soft <span class="hlt">X-ray</span> imaging techniques for calculating the Earth's dayside boundaries</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Connor, Hyunju; Kuntz, Kip; Sibeck, David; Collier, Michael; Aryan, Homayon; Branduardi-Raymont, Graziella; Collado-Vega, Yaireska; Porter, Frederick; Purucker, Michael; Snowden, Steven; Raeder, Joachim; Thomas, Nicholas; Walsh, Brian</p> <p>2016-04-01</p> <p>Charged particles and neutral atoms exchange electrons in many space plasma venues. Soft <span class="hlt">X-rays</span> are emitted when highly charged solar wind ions, such as C6+. O7+, and Fe13+, interact with Hydrogen and Helium atoms. Soft <span class="hlt">X-ray</span> images can be a powerful technique to remotely probe the plasma and neutral density structures created when the solar wind interacts with <span class="hlt">planetary</span> exospheres, such as those at the Earth, Moon, Mars, Venus, and comets. The recently selected ESA-China joint spacecraft mission, "Solar wind - Magnetosphere - Ionosphere Link Explorer (SMILE)" will have a soft <span class="hlt">X-ray</span> imager on board and provide pictures of the Earth's dayside system after its launch in 2021. In preparation for this <span class="hlt">future</span> mission, we simulate soft <span class="hlt">X-ray</span> images of the Earth's dayside system, using the OpenGGCM global magnetosphere MHD model and the Hodges model of the Earth's exosphere. Then, we discuss techniques to determine the location of the Earth's dayside boundaries (bow shock and magnetopause) from the soft <span class="hlt">X-ray</span> images.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001NIMPA.458..132B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001NIMPA.458..132B"><span>The <span class="hlt">X-ray</span> imager on AXO</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Budtz-Jørgensen, C.; Kuvvetli, I.; Westergaard, N. J.; Jonasson, P.; Reglero, V.; Eyles, C.</p> <p>2001-02-01</p> <p>DSRI has initiated a development program of CZT <span class="hlt">X-ray</span> and gamma-ray detectors employing strip readout techniques. A dramatic improvement of the energy response was found operating the detectors as the so-called drift detectors. For the electronic readout, modern ASIC chips were investigated. Modular design and the low-power electronics will make large area detectors using the drift strip method feasible. The performance of a prototype CZT system will be presented and discussed. One such detector system has been proposed for <span class="hlt">future</span> space missions: the <span class="hlt">X-Ray</span> Imager (XRI) on the Atmospheric <span class="hlt">X-ray</span> Observatory (AXO), which is a mission proposed to the Danish Small Satellite Program and is dedicated to observations of <span class="hlt">X-ray</span> generating processes in the Earth's atmosphere. Of special interest will be simultaneous optical and <span class="hlt">X-ray</span> observations of sprites that are flashes appearing directly above an active thunderstorm system. Additional objective is a detailed mapping of the auroral <span class="hlt">X-ray</span> and optical emission. XRI comprises a coded mask and a 20×40 cm 2 CZT detector array covering an energy range from 5 to 200 keV.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014xru..confE.194T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014xru..confE.194T"><span>The potential of <span class="hlt">X-ray</span> polarimetry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tamborra, F.</p> <p>2014-07-01</p> <p>Up-scattering of low-energy photons by Inverse Compton processes in a hot gas of electrons (i.e. Comptonization) is a common astrophysical mechanism particularly important in accreting systems like <span class="hlt">X-ray</span> binaries (XRBs) and Active Galactic Nuclei (AGN). Polarization signals produced by scattering strongly depend on the optical thickness and geometry of the scattering medium as well as on the observer's viewing angle. The polarization degree and angle can be used to constrain, for example, the still unknown parameters which characterize the hot corona responsible for the production of <span class="hlt">X-ray</span> radiation in AGN or the dominant mechanism responsible for the broadening of the Iron K-alpha emission line whose origin is still a matter of debate in the case of low mass <span class="hlt">X-ray</span> binaries with a neutron star. Conducting accurate Monte Carlo simulations we show the potential of <span class="hlt">X-ray</span> polarimetry, a new perspective of <span class="hlt">X-ray</span> astronomy. The spectroscopic part of our results can already be exploited today in the light of XMM-Newton and Chandra data and is even more appealing in the perspective of data from NuStar and <span class="hlt">future</span> <span class="hlt">X-ray</span> missions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://kidshealth.org/en/parents/xray-foot.html','NIH-MEDLINEPLUS'); return false;" href="https://kidshealth.org/en/parents/xray-foot.html"><span><span class="hlt">X-Ray</span> Exam: Foot</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... Habits for TV, Video Games, and the Internet <span class="hlt">X-Ray</span> Exam: Foot KidsHealth > For Parents > <span class="hlt">X-Ray</span> Exam: Foot Print A A A What's in ... You Have Questions What It Is A foot <span class="hlt">X-ray</span> is a safe and painless test that uses ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://kidshealth.org/en/parents/xray-exam-wrist.html','NIH-MEDLINEPLUS'); return false;" href="https://kidshealth.org/en/parents/xray-exam-wrist.html"><span><span class="hlt">X-Ray</span> Exam: Wrist</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... Habits for TV, Video Games, and the Internet <span class="hlt">X-Ray</span> Exam: Wrist KidsHealth > For Parents > <span class="hlt">X-Ray</span> Exam: Wrist Print A A A What's in ... You Have Questions What It Is A wrist <span class="hlt">X-ray</span> is a safe and painless test that uses ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://kidshealth.org/en/parents/xray-ankle.html','NIH-MEDLINEPLUS'); return false;" href="https://kidshealth.org/en/parents/xray-ankle.html"><span><span class="hlt">X-Ray</span> Exam: Ankle</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... Habits for TV, Video Games, and the Internet <span class="hlt">X-Ray</span> Exam: Ankle KidsHealth > For Parents > <span class="hlt">X-Ray</span> Exam: Ankle Print A A A What's in ... You Have Questions What It Is An ankle <span class="hlt">X-ray</span> is a safe and painless test that uses ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://kidshealth.org/en/parents/xray-finger.html','NIH-MEDLINEPLUS'); return false;" href="https://kidshealth.org/en/parents/xray-finger.html"><span><span class="hlt">X-Ray</span> Exam: Finger</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... Habits for TV, Video Games, and the Internet <span class="hlt">X-Ray</span> Exam: Finger KidsHealth > For Parents > <span class="hlt">X-Ray</span> Exam: Finger Print A A A What's in ... You Have Questions What It Is A finger <span class="hlt">X-ray</span> is a safe and painless test that uses ...</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://kidshealth.org/en/parents/xray-pelvis.html','NIH-MEDLINEPLUS'); return false;" href="https://kidshealth.org/en/parents/xray-pelvis.html"><span><span class="hlt">X-Ray</span> Exam: Pelvis</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... Habits for TV, Video Games, and the Internet <span class="hlt">X-Ray</span> Exam: Pelvis KidsHealth > For Parents > <span class="hlt">X-Ray</span> Exam: Pelvis Print A A A What's in ... You Have Questions What It Is A pelvis <span class="hlt">X-ray</span> is a safe and painless test that uses ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://kidshealth.org/en/parents/xray-forearm.html','NIH-MEDLINEPLUS'); return false;" href="https://kidshealth.org/en/parents/xray-forearm.html"><span><span class="hlt">X-Ray</span> Exam: Forearm</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... Habits for TV, Video Games, and the Internet <span class="hlt">X-Ray</span> Exam: Forearm KidsHealth > For Parents > <span class="hlt">X-Ray</span> Exam: Forearm Print A A A What's in ... You Have Questions What It Is A forearm <span class="hlt">X-ray</span> is a safe and painless test that uses ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1015315','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1015315"><span>Tunable <span class="hlt">X-ray</span> source</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Boyce, James R [Williamsburg, VA</p> <p>2011-02-08</p> <p>A method for the production of <span class="hlt">X-ray</span> bunches tunable in both time and energy level by generating multiple photon, <span class="hlt">X-ray</span>, beams through the use of Thomson scattering. The method of the present invention simultaneously produces two <span class="hlt">X-ray</span> pulses that are tunable in energy and/or time.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://kidshealth.org/en/parents/xray-hip.html','NIH-MEDLINEPLUS'); return false;" href="http://kidshealth.org/en/parents/xray-hip.html"><span><span class="hlt">X-Ray</span> Exam: Hip</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... Old Feeding Your 1- to 2-Year-Old <span class="hlt">X-Ray</span> Exam: Hip KidsHealth > For Parents > <span class="hlt">X-Ray</span> Exam: Hip A A A What's in this ... español Radiografía: cadera What It Is A hip <span class="hlt">X-ray</span> is a safe and painless test that uses ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://kidshealth.org/en/parents/xray-exam-wrist.html','NIH-MEDLINEPLUS'); return false;" href="http://kidshealth.org/en/parents/xray-exam-wrist.html"><span><span class="hlt">X-Ray</span> Exam: Wrist</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... Old Feeding Your 1- to 2-Year-Old <span class="hlt">X-Ray</span> Exam: Wrist KidsHealth > For Parents > <span class="hlt">X-Ray</span> Exam: Wrist A A A What's in this ... español Radiografía: muñeca What It Is A wrist <span class="hlt">X-ray</span> is a safe and painless test that uses ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://kidshealth.org/en/parents/xray-ankle.html','NIH-MEDLINEPLUS'); return false;" href="http://kidshealth.org/en/parents/xray-ankle.html"><span><span class="hlt">X-Ray</span> Exam: Ankle</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... Old Feeding Your 1- to 2-Year-Old <span class="hlt">X-Ray</span> Exam: Ankle KidsHealth > For Parents > <span class="hlt">X-Ray</span> Exam: Ankle A A A What's in this ... español Radiografía: tobillo What It Is An ankle <span class="hlt">X-ray</span> is a safe and painless test that uses ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://kidshealth.org/en/parents/xray-foot.html','NIH-MEDLINEPLUS'); return false;" href="http://kidshealth.org/en/parents/xray-foot.html"><span><span class="hlt">X-Ray</span> Exam: Foot</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... Old Feeding Your 1- to 2-Year-Old <span class="hlt">X-Ray</span> Exam: Foot KidsHealth > For Parents > <span class="hlt">X-Ray</span> Exam: Foot A A A What's in this ... español Radiografía: pie What It Is A foot <span class="hlt">X-ray</span> is a safe and painless test that uses ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19940006576','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19940006576"><span>SMM <span class="hlt">x</span> <span class="hlt">ray</span> polychromator</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Saba, J. L. R.</p> <p>1993-01-01</p> <p>The objective of the <span class="hlt">X-ray</span> Polychromator (XRP) experiment was to study the physical properties of solar flare plasma and its relation to the parent active region to understand better the flare mechanism and related solar activity. Observations were made to determine the temperature, density, and dynamic structure of the pre-flare and flare plasma as a function of wavelength, space and time, the extent to which the flare plasma departs from thermal equilibrium, and the variation of this departure with time. The experiment also determines the temperature and density structure of active regions and flare-induced changes in the regions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19860000806','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19860000806"><span><span class="hlt">X-ray</span> satellite</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1985-01-01</p> <p>An overview of the second quarter 1985 development of the <span class="hlt">X-ray</span> satellite project is presented. It is shown that the project is proceeding according to plan and that the projected launch date of September 9, 1987 is on schedule. An overview of the work completed and underway on the systems, subsystems, payload, assembly, ground equipment and interfaces is presented. Problem areas shown include cost increases in the area of focal instrumentation, the star sensor light scattering requirements, and postponements in the data transmission subsystems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19940008710','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19940008710"><span><span class="hlt">Planetary</span> protection implementation on <span class="hlt">future</span> Mars lander missions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Howell, Robert; Devincenzi, Donald L.</p> <p>1993-01-01</p> <p>A workshop was convened to discuss the subject of <span class="hlt">planetary</span> protection implementation for Mars lander missions. It was sponsored and organized by the Exobiology Implementation Team of the U.S./Russian Joint Working Group on Space Biomedical and Life Support Systems. The objective of the workshop was to discuss <span class="hlt">planetary</span> protection issues for the Russian Mars '94 mission, which is currently under development, as well as for additional <span class="hlt">future</span> Mars lander missions including the planned Mars '96 and U.S. MESUR Pathfinder and Network missions. A series of invited presentations was made to ensure that workshop participants had access to information relevant to the planned discussions. The topics summarized in this report include exobiology science objectives for Mars exploration, current international policy on <span class="hlt">planetary</span> protection, <span class="hlt">planetary</span> protection requirements developed for earlier missions, mission plans and designs for <span class="hlt">future</span> U.S. and Russian Mars landers, biological contamination of spacecraft components, and techniques for spacecraft bioload reduction. In addition, the recent recommendations of the U.S. Space Studies Board (SSB) on this subject were also summarized. Much of the discussion focused on the recommendations of the SSB. The SSB proposed relaxing the <span class="hlt">planetary</span> protection requirements for those Mars lander missions that do not contain life detection experiments, but maintaining Viking-like requirements for those missions that do contain life detection experiments. The SSB recommendations were found to be acceptable as a guide for <span class="hlt">future</span> missions, although many questions and concerns about interpretation were raised and are summarized. Significant among the concerns was the need for more quantitative guidelines to prevent misinterpretation by project offices and better access to and use of the Viking data base of bioassays to specify microbial burden targets. Among the questions raised were how will the SSB recommendations be integrated with existing</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1993paal.work...13H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1993paal.work...13H"><span><span class="hlt">Planetary</span> protection implementation on <span class="hlt">future</span> Mars lander missions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Howell, Robert; Devincenzi, Donald L.</p> <p>1993-06-01</p> <p>A workshop was convened to discuss the subject of <span class="hlt">planetary</span> protection implementation for Mars lander missions. It was sponsored and organized by the Exobiology Implementation Team of the U.S./Russian Joint Working Group on Space Biomedical and Life Support Systems. The objective of the workshop was to discuss <span class="hlt">planetary</span> protection issues for the Russian Mars '94 mission, which is currently under development, as well as for additional <span class="hlt">future</span> Mars lander missions including the planned Mars '96 and U.S. MESUR Pathfinder and Network missions. A series of invited presentations was made to ensure that workshop participants had access to information relevant to the planned discussions. The topics summarized in this report include exobiology science objectives for Mars exploration, current international policy on <span class="hlt">planetary</span> protection, <span class="hlt">planetary</span> protection requirements developed for earlier missions, mission plans and designs for <span class="hlt">future</span> U.S. and Russian Mars landers, biological contamination of spacecraft components, and techniques for spacecraft bioload reduction. In addition, the recent recommendations of the U.S. Space Studies Board (SSB) on this subject were also summarized. Much of the discussion focused on the recommendations of the SSB. The SSB proposed relaxing the <span class="hlt">planetary</span> protection requirements for those Mars lander missions that do not contain life detection experiments, but maintaining Viking-like requirements for those missions that do contain life detection experiments. The SSB recommendations were found to be acceptable as a guide for <span class="hlt">future</span> missions, although many questions and concerns about interpretation were raised and are summarized. Significant among the concerns was the need for more quantitative guidelines to prevent misinterpretation by project offices and better access to and use of the Viking data base of bio-assays to specify microbial burden targets. Among the questions raised were how will the SSB recommendations be integrated with existing</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/868109','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/868109"><span><span class="hlt">X-ray</span> lithography source</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Piestrup, Melvin A.; Boyers, David G.; Pincus, Cary</p> <p>1991-01-01</p> <p>A high-intensity, inexpensive <span class="hlt">X-ray</span> source for <span class="hlt">X-ray</span> lithography for the production of integrated circuits. Foil stacks are bombarded with a high-energy electron beam of 25 to 250 MeV to produce a flux of soft <span class="hlt">X-rays</span> of 500 eV to 3 keV. Methods of increasing the total <span class="hlt">X-ray</span> power and making the cross section of the <span class="hlt">X-ray</span> beam uniform are described. Methods of obtaining the desired <span class="hlt">X-ray</span>-beam field size, optimum frequency spectrum and elminating the neutron flux are all described. A method of obtaining a plurality of station operation is also described which makes the process more efficient and economical. The satisfying of these issues makes transition radiation an exellent moderate-priced <span class="hlt">X-ray</span> source for lithography.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/7083850','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/biblio/7083850"><span><span class="hlt">X-ray</span> lithography source</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Piestrup, M.A.; Boyers, D.G.; Pincus, C.</p> <p>1991-12-31</p> <p>A high-intensity, inexpensive <span class="hlt">X-ray</span> source for <span class="hlt">X-ray</span> lithography for the production of integrated circuits is disclosed. Foil stacks are bombarded with a high-energy electron beam of 25 to 250 MeV to produce a flux of soft <span class="hlt">X-rays</span> of 500 eV to 3 keV. Methods of increasing the total <span class="hlt">X-ray</span> power and making the cross section of the <span class="hlt">X-ray</span> beam uniform are described. Methods of obtaining the desired <span class="hlt">X-ray</span>-beam field size, optimum frequency spectrum and eliminating the neutron flux are all described. A method of obtaining a plurality of station operation is also described which makes the process more efficient and economical. The satisfying of these issues makes transition radiation an excellent moderate-priced <span class="hlt">X-ray</span> source for lithography. 26 figures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004SPIE.5570..133K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004SPIE.5570..133K"><span>Study of highly integrated payload architectures for <span class="hlt">future</span> <span class="hlt">planetary</span> missions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kraft, Stefan; Moorhouse, Joseph; Mieremet, Arjan L.; Collon, Maximilien; Montella, Jarno; Beijersbergen, Marco; Harris, J.; van den Berg, Marcel L.; Atzei, Alessandro; Lyngvi, Aleksander; Renton, Daniel; Erd, Christian; Falkner, Peter</p> <p>2004-11-01</p> <p><span class="hlt">Future</span> <span class="hlt">planetary</span> missions will require advanced, smart, low resource payloads and satellites to enable the exploration of our solar system in a more frequent, timely and multi-mission manner. A viable route towards low resource science instrumentation is the concept of Highly Integrated Payload Suites (HIPS), which was introduced during the re-assessment of the payload of the BepiColombo (BC) Mercury <span class="hlt">Planetary</span> Orbiter (MPO). Considerable mass and power savings were demonstrated throughout the instrumentation by improved definition of the instrument design, a higher level of integration, and identification of resource drivers. The higher integration and associated synergy effects permitted optimisation of the payload performance at minimum investment while still meeting the demanding science requirements. For the specific example of the BepiColombo MPO, the mass reduction by designing the instruments towards a Highly Integrated Payload Suite was found to be about 60%. This has endorsed the acceptance of a number of additional instruments as core payload of the BC MPO thereby enhancing the scientific return. This promising strategic approach and concept is now applied to a set of <span class="hlt">planetary</span> mission studies for <span class="hlt">future</span> exploration of the solar system. Innovative technologies, miniaturised electronics and advanced remote sensing technologies are the baseline for a generic approach to payload integration, which is here investigated also in the context of largely differing mission requirements. A review of the approach and the implications to the generic concept as found from the applications to the mission studies are presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/11537370','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11537370"><span><span class="hlt">Planetary</span> protection policy overview and application to <span class="hlt">future</span> missions.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Rummel, J D</p> <p>1989-01-01</p> <p>The 1967 treaty on the peaceful uses of outer space reflected both concerns associated with the unknown nature of the space environment and the desire of the world scientific community to preserve the pristine nature of celestial objects until such times as they could be studied in an effective manner. Since 1967, NASA has issued policy directives that have adopted the guidelines of COSPAR for protecting the planets from contamination by Earth organisms and for protecting the Earth from the unknown. This paper presents the current status of <span class="hlt">planetary</span> protection (quarantine) policy within NASA, and a prospectus on how <span class="hlt">planetary</span> protection and back contamination issues might be addressed in relation to <span class="hlt">future</span> missions envisioned for development by NASA either independently, or in cooperation with the space agencies of other nations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003AGUFM.V41B..02M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003AGUFM.V41B..02M"><span><span class="hlt">X-Ray</span> Microdiffraction at Megabar Pressures</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mao, H.</p> <p>2003-12-01</p> <p>High-pressure <span class="hlt">x-ray</span> diffraction (XRD) provides unique, important sources of structural information of minerals in the Earth's deep interior, but encounters major limitations. The restriction to forward diffraction geometry (2θ less than 90° ) severely limits the accuracy. With the 50-5 μ m size <span class="hlt">x-ray</span> beam typically used to probe samples at 30-200 GPa, the number of crystals covered by the <span class="hlt">x-ray</span> beam is often too few for good polycrystalline XRD, but too numerous for single-crystal XRD. Single-crystal XRD method with monochromatic <span class="hlt">x-ray</span> source and 2-d detector works satisfactorily for crystal size larger than 20 μ m, but when the crystal is significantly less than 5 μ m, the sample signals are often overwhelmed by the background. Energy dispersive XRD with polychromatic x-radiation has been used successfully to determine unit-cell parameters of smaller single crystals, but the intensity information is unusable for structural refinement because this method requires rotation of the small crystal relative to the small <span class="hlt">x-ray</span> beam. Recent integration of panoramic diamond anvil cell1 (PDAC) with synchrotron <span class="hlt">x-ray</span> microdiffraction2 (XRMD) method has finally overcome these limitations and can potentially revolutionize the high-pressure XRD field. This XRMD method focuses polychromatic x-radiation to submicrometer size to resolve very small single crystals, and collects Laue spots with a 2-d CCD detector. The PDAC allows complete forward, 90° , and back scatterings, while the background signal is minimized by directing the incident <span class="hlt">x-ray</span> beam through single-crystal diamonds (i.e., avoiding the beryllium seats and gasket). The incident beam can be changed to monochromatic, tuned through the full energy (wavelength) range, and focused to the identical submicrometer spot for d-spacing determination of each Laue spot. All polychromatic Laue spots are collected simultaneously from the same <span class="hlt">x-ray</span> sampled volume, thus reliable for structure determination. The development</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20000034250','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20000034250"><span>Hard <span class="hlt">X-Ray</span> Emission of <span class="hlt">X-Ray</span> Bursters</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kaaret, P.</p> <p>1999-01-01</p> <p>The primary goal of this proposal was to perform an accurate measurement of the broadband <span class="hlt">x-ray</span> spectrum of a neutron-star low-mass <span class="hlt">x-ray</span> binary found in a hard <span class="hlt">x-ray</span> state. This goal was accomplished using data obtained under another proposal, which has provided exciting new information on the hard <span class="hlt">x-ray</span> emission of neutron-star low-mass <span class="hlt">x-ray</span> binaries. In "BeppoSAX Observations of the Atoll <span class="hlt">X-Ray</span> Binary 4U0614+091", we present our analysis of the spectrum of 4U0614+091 over the energy band from 0.3-150 keV. Our data confirm the presence of a hard <span class="hlt">x-ray</span> tail that can be modeled as thermal Comptonization of low-energy photons on electrons having a very high temperature, greater than 220 keV, or as a non-thermal powerlaw. Such a very hard <span class="hlt">x-ray</span> spectrum has not been previously seen from neutron-star low-mass <span class="hlt">x-ray</span> binaries. We also detected a spectral feature that can be interpreted as reprocessing, via Compton reflection, of the direct emission by an optically-thick disk and found a correlation between the photon index of the power-law tail and the fraction of radiation reflected which is similar to the correlation found for black hole candidate <span class="hlt">x-ray</span> binaries and Seyfert galaxies. A secondary goal was to measure the timing properties of the <span class="hlt">x-ray</span> emission from neutronstar low-mass <span class="hlt">x-ray</span> binaries in their low/hard states.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/10182273','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/10182273"><span>Subgroup report on hard <span class="hlt">x-ray</span> microprobes</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ice, G.E.; Barbee, T.; Bionta, R.; Howells, M.; Thompson, A.C.; Yun, W.</p> <p>1994-09-01</p> <p>The increasing availability of synchrotron <span class="hlt">x-ray</span> sources has stimulated the development of advanced hard <span class="hlt">x-ray</span> (E{>=}5 keV) microprobes. New <span class="hlt">x-ray</span> optics have been demonstrated which show promise for achieving intense submicron hard <span class="hlt">x-ray</span> probes. These probes will be used for extraordinary elemental detection by <span class="hlt">x-ray</span> fluorescence/absorption and for microdiffraction to identify phase and strain. The inherent elemental and crystallographic sensitivity of an <span class="hlt">x-ray</span> microprobe and its inherently nondestructive and penetrating nature makes the development of an advanced hard <span class="hlt">x-ray</span> microprobe an important national goal. In this workshop state-of-the-art hard <span class="hlt">x-ray</span> microprobe optics were described and <span class="hlt">future</span> directions were discussed. Gene Ice, Oak Ridge National Laboratory (ORNL), presented an overview of the current status of hard <span class="hlt">x-ray</span> microprobe optics and described the use of crystal spectrometers to improve minimum detectable limits in fluorescent microprobe experiments. Al Thompson, Lawrence Berkeley Laboratory (LBL), described work at the Center for <span class="hlt">X-ray</span> Optics to develop a hard <span class="hlt">x-ray</span> microprobe based on Kirkpatrick-Baez (KB) optics. Al Thompson also showed the results of some experimental measurements with their KB optics. Malcolm Howells presented a method for bending elliptical mirrors and Troy Barbee commented on the use of graded d spacings to achieve highest efficiency in KB multilayer microfocusing. Richard Bionta, Lawrence Livermore National Laboratory (LLNL), described the development of the first hard <span class="hlt">x-ray</span> zone plates and <span class="hlt">future</span> promise of so called {open_quotes}jelly roll{close_quotes} or sputter slice zone plates. Wenbing Yun, Argonne National Laboratory (ANL), described characterization of jelly roll and lithographically produced zone plates and described the application of zone plates to focus extremely narrow bandwidths by nuclear resonance. This report summarizes the presentations of the workshop subgroup on hard <span class="hlt">x-ray</span> microprobes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017HEAD...1610823J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017HEAD...1610823J"><span>An <span class="hlt">X-Ray</span> Study of NGC 7331</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jin, Ruolan; Kong, Albert K. H.</p> <p>2017-08-01</p> <p>We report on Chandra <span class="hlt">X-ray</span> Observatory ACIS-S observations of the spiral galaxy NGC 7331. There are 50 <span class="hlt">X-ray</span> point sources, including SN 2014C, identified by combining five observations taken between 2001 and 2015 within the optical D25 region of NGC 7331 with a signal to noise ratio (S/N) larger than 3. The detection limit of our sample is 1.3x1038 ergs s-1 in the 0.5-7.0 keV energy band. Fifteen of them are variable with variability larger than 3σ. The cumulative luminosity function of point sources can be fitted with a broken power-law with a luminosity break at 3.6x1038 ergs s-1 while the slope is 0.6 and 2.04 before and after the break, respectively. This may indicate a mixture of bright and young sources on the spiral arms, and older disk populations as studied in other late type galaxies. For the five sources with net counts larger than 120, the spectral model fittings are carried out with absorbed power-law, Raymond-Smith and blackbody models. The spectral fitting of SN 2014C shows a decrease of column density with time and the photon indices vary from -0.24 to 0.87. As for the other four sources, the average power-law photon index is about 1.6. By adopting the classification method proposed by Prestwich et al. (2003) according to the <span class="hlt">X-ray</span> color-color diagram of the sources with S/N larger than 4, we find 9 sources that are likely to be low-mass <span class="hlt">X-ray</span> binaries. We plan to use the observations taken with the Hubble Space Telescope (HST) Wide Field and <span class="hlt">Planetary</span> Camera 2 (WFPC2) and Wide Field Camera 3 (WFC3) to identify optical counterparts lying in the error ellipses of <span class="hlt">X-ray</span> sources in the <span class="hlt">future</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20060025553&hterms=active+space+radiation&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dactive%2Bspace%2Bradiation','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20060025553&hterms=active+space+radiation&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dactive%2Bspace%2Bradiation"><span><span class="hlt">X-Ray</span> Detector Research at MSFC for Space Applications</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gaskin, Jessica</p> <p>2006-01-01</p> <p>NASA's Vision for Space Exploration has specific goals aimed at exploring the Solar System. This vision, under presidential mandate includes landing humans on the moon before the end of the next decade, paving the way for eventual journeys to Mars and beyond. The first missions to the moon will be in the form of both Orbiters and Landers, with the goal of paving the way for human return. One of the instruments we are currently working on,in collaboration with Brookhaven National Laboratory, is a lunar orbiter fluorescent <span class="hlt">x-ray</span> spectrometer to finely map the light elements (down to Carbon) on surface of the moon. Funded NASA s <span class="hlt">Planetary</span> Instrument Definition and Development Program the instrument is based on silicon drift detector arrays read out by custom ASICs. These offer the promise of high spectral resolution, necessary for resolving weak lines against a strong background continuum, and very low power requirements, necessary for large areas (greater than 500 square centimeters) required for <span class="hlt">future</span> lunar missions. Further, the inherent radiation hardness of these detectors makes them ideal candidates for exploring the Jovian system, where the harsh radiation environment from Jupiter s radiation belts creates unfavorable detector conditions. Looking beyond our solar system, in the hard <span class="hlt">x-ray</span> regime (20-80keV.), we are studying Cadmium-Zinc-Telluride pixilated detectors as feasible candidates for focal plane detectors of a hard <span class="hlt">x-ray</span> telescope. This energy region bridges the gap between thermal and non-thermal <span class="hlt">x-ray</span> emission from astronomical sources, will allow us to better understand supernovae nucleosynthesis (such as through the Ti-44 lines at 68keV and 78keV), Active Galactic Nuclei and other compact objects, more completely. The detectors that we are characterizing are 2mm in thickness and are pixilated with a 16x16 array of 300 micrometer pitch pixels (50micometer gap). These detectors are designed at Rutherford Appleton Laboratory, material is from e</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20060025553&hterms=Rutherford&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DRutherford','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20060025553&hterms=Rutherford&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DRutherford"><span><span class="hlt">X-Ray</span> Detector Research at MSFC for Space Applications</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gaskin, Jessica</p> <p>2006-01-01</p> <p>NASA's Vision for Space Exploration has specific goals aimed at exploring the Solar System. This vision, under presidential mandate includes landing humans on the moon before the end of the next decade, paving the way for eventual journeys to Mars and beyond. The first missions to the moon will be in the form of both Orbiters and Landers, with the goal of paving the way for human return. One of the instruments we are currently working on,in collaboration with Brookhaven National Laboratory, is a lunar orbiter fluorescent <span class="hlt">x-ray</span> spectrometer to finely map the light elements (down to Carbon) on surface of the moon. Funded NASA s <span class="hlt">Planetary</span> Instrument Definition and Development Program the instrument is based on silicon drift detector arrays read out by custom ASICs. These offer the promise of high spectral resolution, necessary for resolving weak lines against a strong background continuum, and very low power requirements, necessary for large areas (greater than 500 square centimeters) required for <span class="hlt">future</span> lunar missions. Further, the inherent radiation hardness of these detectors makes them ideal candidates for exploring the Jovian system, where the harsh radiation environment from Jupiter s radiation belts creates unfavorable detector conditions. Looking beyond our solar system, in the hard <span class="hlt">x-ray</span> regime (20-80keV.), we are studying Cadmium-Zinc-Telluride pixilated detectors as feasible candidates for focal plane detectors of a hard <span class="hlt">x-ray</span> telescope. This energy region bridges the gap between thermal and non-thermal <span class="hlt">x-ray</span> emission from astronomical sources, will allow us to better understand supernovae nucleosynthesis (such as through the Ti-44 lines at 68keV and 78keV), Active Galactic Nuclei and other compact objects, more completely. The detectors that we are characterizing are 2mm in thickness and are pixilated with a 16x16 array of 300 micrometer pitch pixels (50micometer gap). These detectors are designed at Rutherford Appleton Laboratory, material is from e</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20060028185','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20060028185"><span>Aerodynamic Decelerators for <span class="hlt">Planetary</span> Exploration: Past, Present, and <span class="hlt">Future</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cruz, Juna R.; Lingard, J. Stephen</p> <p>2006-01-01</p> <p>In this paper, aerodynamic decelerators are defined as textile devices intended to be deployed at Mach numbers below five. Such aerodynamic decelerators include parachutes and inflatable aerodynamic decelerators (often known as ballutes). Aerodynamic decelerators play a key role in the Entry, Descent, and Landing (EDL) of <span class="hlt">planetary</span> exploration vehicles. Among the functions performed by aerodynamic decelerators for such vehicles are deceleration (often from supersonic to subsonic speeds), minimization of descent rate, providing specific descent rates (so that scientific measurements can be obtained), providing stability (drogue function - either to prevent aeroshell tumbling or to meet instrumentation requirements), effecting further aerodynamic decelerator system deployment (pilot function), providing differences in ballistic coefficients of components to enable separation events, and providing height and timeline to allow for completion of the EDL sequence. Challenging aspects in the development of aerodynamic decelerators for <span class="hlt">planetary</span> exploration missions include: deployment in the unusual combination of high Mach numbers and low dynamic pressures, deployment in the wake behind a blunt-body entry vehicle, stringent mass and volume constraints, and the requirement for high drag and stability. Furthermore, these aerodynamic decelerators must be qualified for flight without access to the exotic operating environment where they are expected to operate. This paper is an introduction to the development and application of aerodynamic decelerators for robotic <span class="hlt">planetary</span> exploration missions (including Earth sample return missions) from the earliest work in the 1960s to new ideas and technologies with possible application to <span class="hlt">future</span> missions. An extensive list of references is provided for additional study.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/874269','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/874269"><span>Miniature <span class="hlt">x-ray</span> source</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Trebes, James E.; Stone, Gary F.; Bell, Perry M.; Robinson, Ronald B.; Chornenky, Victor I.</p> <p>2002-01-01</p> <p>A miniature <span class="hlt">x-ray</span> source capable of producing broad spectrum <span class="hlt">x-ray</span> emission over a wide range of <span class="hlt">x-ray</span> energies. The miniature <span class="hlt">x-ray</span> source comprises a compact vacuum tube assembly containing a cathode, an anode, a high voltage feedthru for delivering high voltage to the anode, a getter for maintaining high vacuum, a connection for an initial vacuum pump down and crimp-off, and a high voltage connection for attaching a compact high voltage cable to the high voltage feedthru. At least a portion of the vacuum tube wall is highly <span class="hlt">x-ray</span> transparent and made, for example, from boron nitride. The compact size and potential for remote operation allows the <span class="hlt">x-ray</span> source, for example, to be placed adjacent to a material sample undergoing analysis or in proximity to the region to be treated for medical applications.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1986QJRAS..27..435P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1986QJRAS..27..435P"><span>British <span class="hlt">X-ray</span> astronomy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pounds, K. A.</p> <p>1986-09-01</p> <p>The development of solar and cosmic <span class="hlt">X-ray</span> studies in the UK, in particular the Skylark and Ariel programs, is discussed. The characteristics and capabilities of the <span class="hlt">X-ray</span> emulsion detector developed to monitor the solar X-radiation in the Skylark program, and of the proportional counter spectrometer developed for solar <span class="hlt">X-ray</span> measurements on the Ariel I satellite are described. The designs and functions of the pin-hole camera, the Bragg crystal spectrometer, and the <span class="hlt">X-ray</span> spectroheliograph are exmained. The Skylark observations of cosmic <span class="hlt">X-ray</span> sources and high-resolution solar spectra, and the Ariel 5 data on cosmic <span class="hlt">X-ray</span> sources are presented. Consideration is given to the Ariel 6, the U.S. Einstein Observatory, Exosat, and ASTRO-C.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/5104544','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5104544"><span>Solar <span class="hlt">X-ray</span> physics</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Bornmann, P.L. )</p> <p>1991-01-01</p> <p>Research on solar <span class="hlt">X-ray</span> phenomena performed by American scientists during 1987-1990 is reviewed. Major topics discussed include solar images observed during quiescent times, the processes observed during solar flares, and the coronal, interplanetary, and terrestrial phenomena associated with solar <span class="hlt">X-ray</span> flares. Particular attention is given to the hard <span class="hlt">X-ray</span> emission observed at the start of the flare, the energy transfer to the soft <span class="hlt">X-ray</span> emitting plasma, the late resolution of the flare as observed in soft <span class="hlt">X-ray</span>, and the rate of occurrence of solar flares as a function of time and latitude. Pertinent aspects of nonflaring, coronal <span class="hlt">X-ray</span> emission and stellar flares are also discussed. 175 refs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110007782','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110007782"><span>Thin Shell, Segmented <span class="hlt">X-Ray</span> Mirrors</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Petre, Robert</p> <p>2010-01-01</p> <p>Thin foil mirrors were introduced as a means of achieving high throughput in an <span class="hlt">X-ray</span> astronomical imaging system in applications for which high angular resolution were not necessary. Since their introduction, their high filling factor, modest mass, relative ease of construction, and modest cost have led to their use in numerous <span class="hlt">X-ray</span> observatories, including the Broad Band <span class="hlt">X-ray</span> Telescope, ASCA, and Suzaku. The introduction of key innovations, including epoxy replicated surfaces, multilayer coatings, and glass mirror substrates, has led to performance improvements, and in their becoming widely used for <span class="hlt">X-ray</span> astronomical imaging at energies above 10 keV. The use of glass substrates has also led to substantial improvement in angular resolution, and thus their incorporation into the NASA concept for the International <span class="hlt">X-ray</span> Observatory with a planned 3 in diameter aperture. This paper traces the development of foil mirrors from their inception in the 1970's through their current and anticipated <span class="hlt">future</span> applications.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20000109984&hterms=fournier&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dfournier','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20000109984&hterms=fournier&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dfournier"><span>Tokamak Spectroscopy for <span class="hlt">X-Ray</span> Astronomy</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fournier, Kevin B.; Finkenthal, M.; Pacella, D.; May, M. J.; Soukhanovskii, V.; Mattioli, M.; Leigheb, M.; Rice, J. E.</p> <p>2000-01-01</p> <p>This paper presents the measured <span class="hlt">x-ray</span> and Extreme Ultraviolet (XUV) spectra of three astrophysically abundant elements (Fe, Ca and Ne) from three different tokamak plasmas. In every case, each spectrum touches on an issue of atomic physics that is important for simulation codes to be used in the analysis of high spectral resolution data from current and <span class="hlt">future</span> <span class="hlt">x-ray</span> telescopes. The utility of the tokamak as a laboratory test bed for astrophysical data is demonstrated. Simple models generated with the HULLAC suite of codes demonstrate how the atomic physics issues studied can affect the interpretation of astrophysical data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AIPC.1221...41Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AIPC.1221...41Z"><span>Glass Monocapillary <span class="hlt">X-ray</span> Optics And Their Applications In <span class="hlt">X-ray</span> Microscopy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zeng, X.; Feser, M.; Huang, E.; Lyon, A.; Yun, W.</p> <p>2010-04-01</p> <p>Elliptical, parabolic and Wolter type glass monocapillaries were fabricated for use as <span class="hlt">x-ray</span> condensers in the energy range of 250 eV to 20 keV. On a routine basis a diameter error of +/-0.4 μm and straightness error of 0.8 μm (peak to valley) can be reached. The final test of condensers was performed at-wavelength by imaging the far field <span class="hlt">x-ray</span> reflection intensity distribution using a laboratory microfocus <span class="hlt">x-ray</span> source. For medium length condensers with a total length <80 mm, a total slope error of 40 μrad rms was obtained. The applications in full-field <span class="hlt">x-ray</span> microscopes and the <span class="hlt">future</span> effort in developing capillary Wolter mirrors based on this technology are reported.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA470862','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA470862"><span><span class="hlt">X-Ray</span> Polarization Imaging</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2006-07-01</p> <p>anatomic structures. Johns and Yaffe (2), building on the work of Alvarez and Macovski (3) and that of Lehmann et al (4), discuss a method for...sources of contrast related to both the wave and par- ticulate nature of <span class="hlt">x</span> <span class="hlt">rays</span>. References 1. Johns PC, Yaffe MJ. <span class="hlt">X-ray</span> characterization of normal and...application to mammography. Med Phys 1985; 12:289–296. 3. Alvarez RE, Macovski A. Energy-selective reconstructions in <span class="hlt">x-ray</span> computerized tomography. Phys</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=x+AND+ray&id=EJ986165','ERIC'); return false;" href="https://eric.ed.gov/?q=x+AND+ray&id=EJ986165"><span>Topological <span class="hlt">X-Rays</span> Revisited</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Lynch, Mark</p> <p>2012-01-01</p> <p>We continue our study of topological <span class="hlt">X-rays</span> begun in Lynch ["Topological <span class="hlt">X-rays</span> and MRI's," iJMEST 33(3) (2002), pp. 389-392]. We modify our definition of a topological magnetic resonance imaging and give an affirmative answer to the question posed there: Can we identify a closed set in a box by defining <span class="hlt">X-rays</span> to probe the interior and without…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=mri&pg=4&id=EJ986165','ERIC'); return false;" href="http://eric.ed.gov/?q=mri&pg=4&id=EJ986165"><span>Topological <span class="hlt">X-Rays</span> Revisited</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Lynch, Mark</p> <p>2012-01-01</p> <p>We continue our study of topological <span class="hlt">X-rays</span> begun in Lynch ["Topological <span class="hlt">X-rays</span> and MRI's," iJMEST 33(3) (2002), pp. 389-392]. We modify our definition of a topological magnetic resonance imaging and give an affirmative answer to the question posed there: Can we identify a closed set in a box by defining <span class="hlt">X-rays</span> to probe the interior and without…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/971436','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/971436"><span><span class="hlt">X-ray</span> Absorption Spectroscopy</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Yano, Junko; Yachandra, Vittal K.</p> <p>2009-07-09</p> <p>This review gives a brief description of the theory and application of <span class="hlt">X-ray</span> absorption spectroscopy, both <span class="hlt">X-ray</span> absorption near edge structure (XANES) and extended <span class="hlt">X-ray</span> absorption fine structure (EXAFS), especially, pertaining to photosynthesis. The advantages and limitations of the methods are discussed. Recent advances in extended EXAFS and polarized EXAFS using oriented membranes and single crystals are explained. Developments in theory in understanding the XANES spectra are described. The application of <span class="hlt">X-ray</span> absorption spectroscopy to the study of the Mn4Ca cluster in Photosystem II is presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004AdSpR..34.2688T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004AdSpR..34.2688T"><span>A hybrid <span class="hlt">X-ray</span> imaging spectrometer for NeXT and the next generation <span class="hlt">X-ray</span> satellite</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tsuru, T. G.; Tanimori, T.; Bamba, A.; Imanishi, K.; Koyama, K.; Kubo, H.; Matsumoto, H.; Miuchi, K.; Nagayoshi, M.; Orito, R.; Takada, A.; Takagi, S.; Tsujimoto, M.; Ueno, M.; Tsunemi, H.; Hayashida, K.; Miyata, E.</p> <p>2004-01-01</p> <p>We propose a new type of wide band <span class="hlt">X-ray</span> imaging spectrometer as a focal plane detector of the super mirror onboard on <span class="hlt">future</span> <span class="hlt">X-ray</span> missions including post Astro-E2. This camera is realized by the hybrid of back illumination CCDs and a back supportless CCD for 0.05-10 keV band, and a Micro Pixel Gas Chamber detecting <span class="hlt">X-rays</span> at 10-80 keV.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22521782','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22521782"><span><span class="hlt">X-RAY</span> POLARIZATION FROM HIGH-MASS <span class="hlt">X-RAY</span> BINARIES</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kallman, T.; Blondin, J.</p> <p>2015-12-10</p> <p><span class="hlt">X-ray</span> astronomy allows study of objects that may be associated with compact objects, i.e., neutron stars or black holes, and also may contain strong magnetic fields. Such objects are categorically nonspherical, and likely noncircular when projected on the sky. Polarization allows study of such geometric effects, and <span class="hlt">X-ray</span> polarimetry is likely to become feasible for a significant number of sources in the <span class="hlt">future</span>. Potential targets for <span class="hlt">future</span> <span class="hlt">X-ray</span> polarization observations are the high-mass <span class="hlt">X-ray</span> binaries (HMXBs), which consist of a compact object in orbit with an early-type star. In this paper we show that <span class="hlt">X-ray</span> polarization from HMXBs has a distinct signature that depends on the source inclination and orbital phase. The presence of the <span class="hlt">X-ray</span> source displaced from the star creates linear polarization even if the primary wind is spherically symmetric whenever the system is viewed away from conjunction. Direct <span class="hlt">X-rays</span> dilute this polarization whenever the <span class="hlt">X-ray</span> source is not eclipsed; at mid-eclipse the net polarization is expected to be small or zero if the wind is circularly symmetric around the line of centers. Resonance line scattering increases the scattering fraction, often by large factors, over the energy band spanned by resonance lines. Real winds are not expected to be spherically symmetric, or circularly symmetric around the line of centers, owing to the combined effects of the compact object gravity and ionization on the wind hydrodynamics. A sample calculation shows that this creates polarization fractions ranging up to tens of percent at mid-eclipse.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20160000363','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20160000363"><span><span class="hlt">X-Ray</span> Polarization from High Mass <span class="hlt">X-Ray</span> Binaries</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kallman, T.; Dorodnitsyn, A.; Blondin, J.</p> <p>2015-01-01</p> <p><span class="hlt">X-ray</span> astronomy allows study of objects which may be associated with compact objects, i.e. neutron stars or black holes, and also may contain strong magnetic fields. Such objects are categorically non-spherical, and likely non-circular when projected on the sky. Polarization allows study of such geometric effects, and <span class="hlt">X-ray</span> polarimetry is likely to become feasible for a significant number of sources in the <span class="hlt">future</span>. A class of potential targets for <span class="hlt">future</span> <span class="hlt">X-ray</span> polarization observations is the high mass <span class="hlt">X-ray</span> binaries (HMXBs), which consist of a compact object in orbit with an early type star. In this paper we show that <span class="hlt">X-ray</span> polarization from HMXBs has a distinct signature which depends on the source inclination and orbital phase. The presence of the <span class="hlt">X-ray</span> source displaced from the star creates linear polarization even if the primary wind is spherically symmetric whenever the system is viewed away from conjunction. Direct <span class="hlt">X-rays</span> dilute this polarization whenever the <span class="hlt">X-ray</span> source is not eclipsed; at mid-eclipse the net polarization is expected to be small or zero if the wind is circularly symmetric around the line of centers. Resonance line scattering increases the scattering fraction, often by large factors, over the energy band spanned by resonance lines. Real winds are not expected to be spherically symmetric, or circularly symmetric around the line of centers, owing to the combined effects of the compact object gravity and ionization on the wind hydrodynamics. A sample calculation shows that this creates polarization fractions ranging up to tens of percent at mid-eclipse.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NaPho..10...75P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NaPho..10...75P"><span><span class="hlt">X-ray</span> photonics: Bending <span class="hlt">X-rays</span> with nanochannels</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pelliccia, Daniele</p> <p>2016-02-01</p> <p><span class="hlt">X-ray</span> counterparts of visible light optical elements are notoriously difficult to realize because the refractive index of all materials is close to unity. It has now been demonstrated that curved waveguides fabricated on a silicon chip can channel and deflect <span class="hlt">X-ray</span> beams by consecutive grazing reflections.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20160008030','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20160008030"><span>Adjustable Grazing-Incidence <span class="hlt">X-Ray</span> Optics</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>O'Dell, Stephen L.; Reid, Paul B.</p> <p>2015-01-01</p> <p>With its unique subarcsecond imaging performance, NASA's Chandra <span class="hlt">X-ray</span> Observatory illustrates the importance of fine angular resolution for <span class="hlt">x-ray</span> astronomy. Indeed, the <span class="hlt">future</span> of <span class="hlt">x-ray</span> astronomy relies upon <span class="hlt">x-ray</span> telescopes with comparable angular resolution but larger aperture areas. Combined with the special requirements of nested grazing-incidence optics, mass, and envelope constraints of space-borne telescopes render such advances technologically and programmatically challenging. The goal of this technology research is to enable the cost-effective fabrication of large-area, lightweight grazing-incidence <span class="hlt">x-ray</span> optics with subarcsecond resolution. Toward this end, the project is developing active <span class="hlt">x-ray</span> optics using slumped-glass mirrors with thin-film piezoelectric arrays for correction of intrinsic or mount-induced distortions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/908117','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/908117"><span>Multilayers for next generation <span class="hlt">x-ray</span> sources</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Bajt, S; Chapman, H N; Spiller, E; Hau-Riege, S; Alameda, J; Nelson, A J; Walton, C C; Kjornrattanawanich, B; Aquila, A; Dollar, F; Gullikson, E; Tarrio, C</p> <p>2007-05-04</p> <p>Multilayers are artificially layered structures that can be used to create optics and optical elements for a broad range of <span class="hlt">x-ray</span> wavelengths, or can be optimized for other applications. The development of next generation <span class="hlt">x-ray</span> sources (synchrotrons and <span class="hlt">x-ray</span> free electron lasers) requires advances in <span class="hlt">x-ray</span> optics. Newly developed multilayer-based mirrors and optical elements enabled efficient band-pass filtering, focusing and time resolved measurements in recent FLASH (Free Electron LASer in Hamburg) experiments. These experiments are providing invaluable feedback on the response of the multilayer structures to high intensity, short pulsed <span class="hlt">x-ray</span> sources. This information is crucial to design optics for <span class="hlt">future</span> <span class="hlt">x-ray</span> free electron lasers and to benchmark computer codes that simulate damage processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19910004171','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19910004171"><span>Development of mercuric iodide uncooled <span class="hlt">x</span> <span class="hlt">ray</span> detectors and spectrometers</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Iwanczyk, Jan S.</p> <p>1990-01-01</p> <p>The results obtained in the development of miniature, lowpower, light weight mercuric iodide, HgI2, <span class="hlt">x</span> <span class="hlt">ray</span> spectrometers for <span class="hlt">future</span> space missions are summarized. It was demonstrated that HgI2 detectors can be employed in a high resolution <span class="hlt">x</span> <span class="hlt">ray</span> spectrometer, operating in a scanning electron microscope. Also, the development of HgI2 <span class="hlt">x</span> <span class="hlt">ray</span> detectors to augment alpha backscattering spectrometers is discussed. These combination instruments allow for the identification of all chemical elements, with the possible exception of hydrogen, and their respective concentrations. Additionally, further investigations of questions regarding radiation damage effects in the HgI2 <span class="hlt">x</span> <span class="hlt">ray</span> detectors are reported.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017CoSka..47..170H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017CoSka..47..170H"><span>JEUMICO: Czech-Bavarian astronomical <span class="hlt">X-ray</span> optics project</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hudec, R.; Döhring, T.</p> <p>2017-07-01</p> <p>Within the project JEUMICO, an acronym for "Joint European Mirror Competence", the Aschaffenburg University of Applied Sciences and the Czech Technical University in Prague started a collaboration to develop mirrors for <span class="hlt">X-ray</span> telescopes. Corresponding mirror segments use substrates of flat silicon wafers which are coated with thin iridium films, as this material is promising high reflectivity in the <span class="hlt">X-ray</span> range of interest. The sputtering parameters are optimized in the context of the expected reflectivity of the coated <span class="hlt">X-ray</span> mirrors. In near <span class="hlt">future</span> measurements of the assembled mirror modules optical performances are planned at an <span class="hlt">X-ray</span> test facility.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20070001550&hterms=shell&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DTitle%26N%3D0%26No%3D80%26Ntt%3Dshell','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20070001550&hterms=shell&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DTitle%26N%3D0%26No%3D80%26Ntt%3Dshell"><span>Status of MSFC <span class="hlt">X-ray</span> Shell Optics Fabrication Capability</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sthal, H. Philip; Gubarev, Mikhail; Ramsey, Brian; Englehaupt, Darell; Speegle, Chet</p> <p>2006-01-01</p> <p>We present details of an MSFC development program of electroformed-nickel replicated grazing incidence optics for <span class="hlt">x-ray</span> imaging. To date a wide variety of mirrors has been produced with diameters ranging from 2.5 cm, for small animal imaging, up to 112 meter, for <span class="hlt">x-ray</span> astronomy. Around 100 intermediate size shells are currently aboard the HERO <span class="hlt">x-ray</span> astronomy balloon payload awaiting launch in Fort Sumner, New mexico. Details of the program are presented together with developments currently underway to improve mirror-shell quality from the current approx. 15 arcsec resolution to below 10 arcsec for <span class="hlt">future</span> <span class="hlt">x-ray</span> astronomy missions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016SPD....47.0636K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016SPD....47.0636K"><span>EXACT - The Solar <span class="hlt">X-Ray</span> Spectrometer CubeSat</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Knuth, Trevor; Glesener, Lindsay; Gebre-Egziabher, Demoz; Vogt, Ryan; Denis, Charles; Weiher, Hannah; Runnels, Joel; Vievering, Juliana</p> <p>2016-05-01</p> <p>The Experiment for <span class="hlt">X-ray</span> Characterization and Timing (EXACT) mission will be a CubeSat based hard <span class="hlt">X-ray</span> spectrometer used for viewing solar flares with high time precision. Solar flares and the related coronal mass ejections affect space weather and the near-Earth environment. EXACT can study the hard <span class="hlt">X-rays</span> generated by the Sun in the declining phase of Solar Cycle 24 in order to probe electron acceleration in solar eruptive events while also serving as a precursor to <span class="hlt">future</span> hard <span class="hlt">X-ray</span> spectrometers that could monitor the Sun continuously.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19890016061','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19890016061"><span><span class="hlt">X-ray</span> based extensometry</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Jordan, E. H.; Pease, D. M.</p> <p>1988-01-01</p> <p>A totally new method of extensometry using an <span class="hlt">X-ray</span> beam was proposed. The intent of the method is to provide a non-contacting technique that is immune to problems associated with density variations in gaseous environments that plague optical methods. <span class="hlt">X-rays</span> are virtually unrefractable even by solids. The new method utilizes <span class="hlt">X-ray</span> induced <span class="hlt">X-ray</span> fluorescence or <span class="hlt">X-ray</span> induced optical fluorescence of targets that have melting temperatures of over 3000 F. Many different variations of the basic approaches are possible. In the year completed, preliminary experiments were completed which strongly suggest that the method is feasible. The <span class="hlt">X-ray</span> induced optical fluorescence method appears to be limited to temperatures below roughly 1600 F because of the overwhelming thermal optical radiation. The <span class="hlt">X-ray</span> induced <span class="hlt">X-ray</span> fluorescence scheme appears feasible up to very high temperatures. In this system there will be an unknown tradeoff between frequency response, cost, and accuracy. The exact tradeoff can only be estimated. It appears that for thermomechanical tests with cycle times on the order of minutes a very reasonable system may be feasible. The intended applications involve very high temperatures in both materials testing and monitoring component testing. Gas turbine engines, rocket engines, and hypersonic vehicles (NASP) all involve measurement needs that could partially be met by the proposed technology.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011APS..NES.F1004A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011APS..NES.F1004A"><span>Dual <span class="hlt">x-ray</span> absorptiometry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Altman, Albert; Aaron, Ronald</p> <p>2011-04-01</p> <p>Dual <span class="hlt">x-ray</span> absorptiometry is widely used in analyzing body composition and imaging. We discuss the physics of the method and exhibit its limitations and show it is related to the Compton and photoelectric contributions to the <span class="hlt">x-ray</span> absorption coefficients of materials.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19810011370','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19810011370"><span><span class="hlt">X-ray</span> position detector</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Garmire, G. (Inventor)</p> <p>1972-01-01</p> <p>An <span class="hlt">X-ray</span> position detector for real time operation is described. A set of proportional counters is arranged into an array which can detect and indicate the position of an <span class="hlt">X-ray</span> interaction within the array, in the X Y plane.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25931097','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25931097"><span>Direct-write <span class="hlt">X-ray</span> lithography using a hard <span class="hlt">X-ray</span> Fresnel zone plate.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lee, Su Yong; Noh, Do Young; Lee, Hae Cheol; Yu, Chung-Jong; Hwu, Yeukuang; Kang, Hyon Chol</p> <p>2015-05-01</p> <p>Results are reported of direct-write <span class="hlt">X-ray</span> lithography using a hard <span class="hlt">X-ray</span> beam focused by a Fresnel zone plate with an outermost zone width of 40 nm. An <span class="hlt">X-ray</span> beam at 7.5 keV focused to a nano-spot was employed to write arbitrary patterns on a photoresist thin film with a resolution better than 25 nm. The resulting pattern dimension depended significantly on the kind of underlying substrate, which was attributed to the lateral spread of electrons generated during <span class="hlt">X-ray</span> irradiation. The proximity effect originated from the diffuse scattering near the focus and electron blur was also observed, which led to an increase in pattern dimension. Since focusing hard <span class="hlt">X-rays</span> to below a 10 nm spot is currently available, the direct-write hard <span class="hlt">X-ray</span> lithography developed in this work has the potential to be a promising <span class="hlt">future</span> lithographic method.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013NIMPA.731...57S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013NIMPA.731...57S"><span><span class="hlt">X-ray</span> detectors in medical imaging</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Spahn, Martin</p> <p>2013-12-01</p> <p>Healthcare systems are subject to continuous adaptation, following trends such as the change of demographic structures, the rise of life-style related and chronic diseases, and the need for efficient and outcome-oriented procedures. This also influences the design of new imaging systems as well as their components. The applications of <span class="hlt">X-ray</span> imaging in the medical field are manifold and have led to dedicated modalities supporting specific imaging requirements, for example in computed tomography (CT), radiography, angiography, surgery or mammography, delivering projection or volumetric imaging data. Depending on the clinical needs, some <span class="hlt">X-ray</span> systems enable diagnostic imaging while others support interventional procedures. <span class="hlt">X-ray</span> detector design requirements for the different medical applications can vary strongly with respect to size and shape, spatial resolution, frame rates and <span class="hlt">X-ray</span> flux, among others. Today, integrating <span class="hlt">X-ray</span> detectors are in common use. They are predominantly based on scintillators (e.g. CsI or Gd2O2S) and arrays of photodiodes made from crystalline silicon (Si) or amorphous silicon (a-Si) or they employ semiconductors (e.g. Se) with active a-Si readout matrices. Ongoing and <span class="hlt">future</span> developments of <span class="hlt">X-ray</span> detectors will include optimization of current state-of-the-art integrating detectors in terms of performance and cost, will enable the usage of large size CMOS-based detectors, and may facilitate photon counting techniques with the potential to further enhance performance characteristics and foster the prospect of new clinical applications.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20020023591','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20020023591"><span>High Resolution <span class="hlt">X-ray</span> Imaging</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cash, Webster</p> <p>2002-01-01</p> <p>NAG5-5020 covered a period of 7.5 years during which a great deal of progress was made in <span class="hlt">x-ray</span> optical techniques under this grant. We survived peer review numerous times during the effort to keep the grant going. In 1994, when the grant started we were actively pursuing the application of spherical mirrors to improving <span class="hlt">x-ray</span> telescopes. We had found that <span class="hlt">x-ray</span> detectors were becoming rapidly more sophisticated and affordable, but that <span class="hlt">x-ray</span> telescopes were only being improved through the intense application of money within the AXAF program. Clearly new techniques for the <span class="hlt">future</span> were needed. We were successful in developing and testing at the HELSTF facility in New Mexico a four reflection coma-corrected telescope made from spheres. We were able to demonstrate 0.3 arcsecond resolution, almost to the diffraction limit of the system. The community as a whole was, at that time, not particularly interested in looking past AXAF (Chandra) and the effort needed to evolve. Since we had reached the diffraction limit using non-Wolter optics we then decided to see if we could build an <span class="hlt">x-ray</span> interferometer in the laboratory. In the lab the potential for improved resolution was substantial. If synthetic aperture telescopes could be built in space, then orders of magnitude improvement would become feasible. In 1998 NASA, under the direction of Dr. Nick White of Goddard, started a study to assess the potential and feasibility of <span class="hlt">x-ray</span> interferometry in space. My work became of central interest to the committee because it indicated that such was possible. In early 1999 we had the breakthrough that allowed us build a practical interferometer. By using flats and hooking up with the Marshall Space Flight Center facilities we were able to demonstrate fringes at 1.25keV on a one millimeter baseline. This actual laboratory demonstration provided the solid proof of concept that NASA needed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/525918','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/525918"><span><span class="hlt">X-ray</span> microtomography of porous media at BNL</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Dowd, B.</p> <p>1997-02-01</p> <p>This session is comprised of pertinent information about the historical aspects, current status of research, technical achievements, and <span class="hlt">future</span> plans in <span class="hlt">X-ray</span> computed microtomography at Brookhaven National Laboratories. An explanation with specifications and diagrams of <span class="hlt">X-ray</span> instrumentation is provided. Several high resolution 3-D color images of reservoir rock drill cores and other materials are included.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/985339','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/985339"><span><span class="hlt">X-ray</span> shearing interferometer</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Koch, Jeffrey A [Livermore, CA</p> <p>2003-07-08</p> <p>An <span class="hlt">x-ray</span> interferometer for analyzing high density plasmas and optically opaque materials includes a point-like <span class="hlt">x-ray</span> source for providing a broadband <span class="hlt">x-ray</span> source. The <span class="hlt">x-rays</span> are directed through a target material and then are reflected by a high-quality ellipsoidally-bent imaging crystal to a diffraction grating disposed at 1.times. magnification. A spherically-bent imaging crystal is employed when the <span class="hlt">x-rays</span> that are incident on the crystal surface are normal to that surface. The diffraction grating produces multiple beams which interfere with one another to produce an interference pattern which contains information about the target. A detector is disposed at the position of the image of the target produced by the interfering beams.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/992933','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/992933"><span><span class="hlt">X-Ray</span> Tomographic Reconstruction</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Bonnie Schmittberger</p> <p>2010-08-25</p> <p>Tomographic scans have revolutionized imaging techniques used in medical and biological research by resolving individual sample slices instead of several superimposed images that are obtained from regular <span class="hlt">x-ray</span> scans. <span class="hlt">X-Ray</span> fluorescence computed tomography, a more specific tomography technique, bombards the sample with synchrotron <span class="hlt">x-rays</span> and detects the fluorescent photons emitted from the sample. However, since <span class="hlt">x-rays</span> are attenuated as they pass through the sample, tomographic scans often produce images with erroneous low densities in areas where the <span class="hlt">x-rays</span> have already passed through most of the sample. To correct for this and correctly reconstruct the data in order to obtain the most accurate images, a program employing iterative methods based on the inverse Radon transform was written. Applying this reconstruction method to a tomographic image recovered some of the lost densities, providing a more accurate image from which element concentrations and internal structure can be determined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19960034341','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19960034341"><span><span class="hlt">X-Ray</span> Diffraction Apparatus</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Blake, David F. (Inventor); Bryson, Charles (Inventor); Freund, Friedmann (Inventor)</p> <p>1996-01-01</p> <p>An <span class="hlt">x-ray</span> diffraction apparatus for use in analyzing the <span class="hlt">x-ray</span> diffraction pattern of a sample is introduced. The apparatus includes a beam source for generating a collimated <span class="hlt">x-ray</span> beam having one or more discrete <span class="hlt">x-ray</span> energies, a holder for holding the sample to be analyzed in the path of the beam, and a charge-coupled device having an array of pixels for detecting, in one or more selected photon energy ranges, <span class="hlt">x-ray</span> diffraction photons produced by irradiating such a sample with said beam. The CCD is coupled to an output unit which receives input information relating to the energies of photons striking each pixel in the CCD, and constructs the diffraction pattern of photons within a selected energy range striking the CCD.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20100036498','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20100036498"><span>Focusing <span class="hlt">X-Ray</span> Telescopes</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>O'Dell, Stephen; Brissenden, Roger; Davis, William; Elsner, Ronald; Elvis, Martin; Freeman, Mark; Gaetz, Terrance; Gorenstein, Paul; Gubarev, Mikhall; Jerlus, Diab; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20100036498'); toggleEditAbsImage('author_20100036498_show'); toggleEditAbsImage('author_20100036498_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20100036498_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20100036498_hide"></p> <p>2010-01-01</p> <p>During the half-century history of <span class="hlt">x-ray</span> astronomy, focusing <span class="hlt">x-ray</span> telescopes, through increased effective area and finer angular resolution, have improved sensitivity by 8 orders of magnitude. Here, we review previous and current <span class="hlt">x-ray</span>-telescope missions. Next, we describe the planned next-generation <span class="hlt">x-ray</span>-astronomy facility, the International <span class="hlt">X-ray</span> Observatory (IXO). We conclude with an overview of a concept for the next next-generation facility, Generation X. Its scientific objectives will require very large areas (about 10,000 sq m) of highly-nested, lightweight grazing-incidence mirrors, with exceptional (about 0.1-arcsec) resolution. Achieving this angular resolution with lightweight mirrors will likely require on-orbit adjustment of alignment and figure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014cosp...40E1247H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014cosp...40E1247H"><span>PDS4 - Positioning the <span class="hlt">Planetary</span> Data System for the <span class="hlt">Future</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hughes, J. Steven; Beebe, Reta; Crichton, Daniel J.; Morgan, Tom</p> <p></p> <p>The <span class="hlt">Planetary</span> Data System (PDS) has just released PDS4, a modernization of the PDS architecture, data standards, and technical infrastructure. This next generation system positions the PDS to meet the demands of the coming decade, including big data, international cooperation, distributed nodes, and multiple ways of analysing and interpreting data. It also addresses three fundamental project goals: providing more efficient data delivery by data providers to the PDS, enabling a stable, long-term usable <span class="hlt">planetary</span> science data archive, and enabling services for the data consumer to find, access, and use the data they require in contemporary data formats. The PDS is an active partner in the International <span class="hlt">Planetary</span> Data Alliance (IPDA), working with space agencies around the world to collaborate and share instruments and scientific data results. The IPDA has had a significant role in developing PDS4 and is promoting the standards and infrastructure toward a world-wide archive. PDS4 is a modern operational system resulting from the application of a lifecycle developed for model-driven software systems for science and is being used to coordinate the science communities. An information model formalizes the system’s information requirements and allows significant but controlled evolution of the system as the science domains and implementation technologies change. PDS4 will provide a scientific research asset that allows current and <span class="hlt">future</span> users to re-analyse the data within new contexts. PDS4 is being used in the early phases of several missions to ensure they have adequate tools and that the system streamlines the preparation and delivery of data to the PDS. Data services are also under development to help in searching, accessing, and using data in formats and structures that will enhance the ability of researchers to perform analysis in cost-constrained environments. This presentation will cover the PDS4 project, system architecture, and its current status as a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1337631','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1337631"><span><span class="hlt">X-ray</span> monitoring optical elements</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Stoupin, Stanislav; Shvydko, Yury; Katsoudas, John; Blank, Vladimir D.; Terentyev, Sergey A.</p> <p>2016-12-27</p> <p>An <span class="hlt">X-ray</span> article and method for analyzing hard <span class="hlt">X-rays</span> which have interacted with a test system. The <span class="hlt">X-ray</span> article is operative to diffract or otherwise process <span class="hlt">X-rays</span> from an input <span class="hlt">X-ray</span> beam which have interacted with the test system and at the same time provide an electrical circuit adapted to collect photoelectrons emitted from an <span class="hlt">X-ray</span> optical element of the <span class="hlt">X-ray</span> article to analyze features of the test system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6898250','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6898250"><span><span class="hlt">X-ray</span> diagnostics for TFTR</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>von Goeler, S.; Hill, K.W.; Bitter, M.</p> <p>1982-12-01</p> <p>A short description of the <span class="hlt">x-ray</span> diagnostic preparation for the TFTR tokamak is given. The <span class="hlt">x-ray</span> equipment consists of the limiter <span class="hlt">x-ray</span> monitoring system, the soft <span class="hlt">x-ray</span> pulse-height-analysis-system, the soft <span class="hlt">x-ray</span> imaging system and the <span class="hlt">x-ray</span> crystal spectrometer. Particular attention is given to the radiation protection of the <span class="hlt">x-ray</span> systems from the neutron environment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20040062014&hterms=science+topic&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dscience%2Btopic','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20040062014&hterms=science+topic&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dscience%2Btopic"><span>Lunar and <span class="hlt">Planetary</span> Science XXXV: <span class="hlt">Future</span> Missions to the Moon</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2004-01-01</p> <p>This document contained the following topics: A Miniature Mass Spectrometer Module; SELENE Gamma Ray Spectrometer Using Ge Detector Cooled by Stirling Cryocooler; Lunar Elemental Composition and Investigations with D-CIXS <span class="hlt">X-Ray</span> Mapping Spectrometer on SMART-1; <span class="hlt">X-Ray</span> Fluorescence Spectrometer Onboard the SELENE Lunar Orbiter: Its Science and Instrument; Detectability of Degradation of Lunar Impact Craters by SELENE Terrain Camera; Study of the Apollo 16 Landing Site: As a Standard Site for the SELENE Multiband Imager; Selection of Targets for the SMART-1 Infrared Spectrometer (SIR); Development of a Telescopic Imaging Spectrometer for the Moon; The Lunar Seismic Network: Mission Update.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.4993K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.4993K"><span>Past missions - the best way to train <span class="hlt">future</span> <span class="hlt">planetary</span> researchers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kozlova, Natalia; Solodovnikova, Anastasiya; Zubarev, Anatoly; Garov, Andrey; Patraty, Vyacheslav; Kokhanov, Alexander; Karachevtseva, Irina; Nadezhdina, Irina; Konopikhin, Anatoly; Oberst, Juergen</p> <p>2015-04-01</p> <p>Practice shows that it is much more interesting and useful to learn from real examples than on imaginary tasks from exercise books. The more technologies and software improves and develops, the more information and new products can be obtained from new processing of archive information collected by past <span class="hlt">planetary</span> missions. So at MIIGAiK we carry out modern processing of lunar panoramic images obtained by Soviet Lunokhod missions (1970-1973). During two years of the study, which is a part of PRoViDE project (http://www.provide-space.eu/), many students, PhD students, young scientists, as well as professors have taken part in this research. Processing of the data obtained so long ago requires development of specific methods, techniques, special software and extraordinary approach. All these points help to interest young people in <span class="hlt">planetary</span> science and develop their skills as researchers. Another advantage of data from previous missions is that you can compare your results with the ones obtained during the mission. This also helps to test the developed techniques and software on real data and adjust them for implementation in <span class="hlt">future</span> missions. The work on Lunokhod data processing became the basis of master and PhD theses of MIIGAiK students and scientists at MExLab. Acknowledgments: The research leading to these results has received funding from the European Community's Seventh Framework Programme (FP7/2007-2013) under grant agreement No 312377 PRoViDE.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012APS..DPPBO4004H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012APS..DPPBO4004H"><span>Burning DT Plasmas with Ultrafast Soft <span class="hlt">X-Ray</span> Pulses</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hu, S. X.; Goncharov, V. N.; Skupsky, S.</p> <p>2012-10-01</p> <p>Fast ignition with narrowband, coherent ultrafast soft <span class="hlt">x-ray</span> pulsesfootnotetextS. X. Hu, V. N. Goncharov, and S. Skupsky, ``Burning Plasmas with Ultrashort Soft-<span class="hlt">X-Ray</span> Flashing,'' to be published in Physics of Plasmas. has been investigated for cryogenic deuterium--tritium (DT) plasma conditions achieved on the OMEGA Laser System. In contrast to using hard <span class="hlt">x-rays</span> (hν = 3 to 6 keV) proposed in the original <span class="hlt">x-ray</span> fast-ignition proposal, we find that soft <span class="hlt">x-ray</span> sources with hν 500-eV photons can be more suitable for igniting the dense DT plasmas. Two-dimensional radiation--hydrodynamics simulations have identified the breakeven conditions for realizing such a ``hybrid'' ignition scheme (direct-drive compression with soft <span class="hlt">x-ray</span> heating) with 50-μm-offset targets: an ˜10-ps soft <span class="hlt">x-ray</span> pulse (hν 500 eV) with a total energy of 500 to 1000 J to be focused into a 10-μm spot size. A variety of <span class="hlt">x-ray</span> pulse parameters have also been investigated for optimization. It is noted that an order of magnitude increase in neutron yield has been predicted even with <span class="hlt">x-ray</span> energy as low as ˜50 J. Scaling this idea to a 1-MJ large-scale NIF target, a gain above ˜30 can be reached with the same soft <span class="hlt">x-ray</span> pulse at 1.65-kJ energy. Even though such energetic <span class="hlt">x-ray</span> sources do not currently exist, we hope that the proposed ignition scheme may stimulate efforts on generating powerful soft <span class="hlt">x-ray</span> sources in <span class="hlt">future</span>. This work was supported by the U.S. Department of Energy Office of Inertial Confinement Fusion under Cooperative Agreement No. DE-FC52-08NA28302.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1999IAUS..183..200H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1999IAUS..183..200H"><span>The <span class="hlt">X-Ray</span> Background and the AGN Luminosity Function</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hasinger, G.</p> <p></p> <p>The deepest <span class="hlt">X-ray</span> surveys performed with ROSAT were able to resolve as much as 70-80% of the 1-2 keV <span class="hlt">X-ray</span> background into resolved sources. Optical follow-up observations were able to identify the majority of faint <span class="hlt">X-ray</span> sources as active galactic nuclei (AGN) out to redshifts of 4.5 as well as a sizeable fraction as groups of galaxies out to redshifts of 0.7. A new population of <span class="hlt">X-ray</span> luminous, optically innocent narrow emission line galaxies (NELGs) at the faintest <span class="hlt">X-ray</span> fluxes is still a matter of debate, most likely many of them are also connected to AGN. First deep surveys with the Japanese ASCA satellite give us a glimpse of the harder <span class="hlt">X-ray</span> background where the bulk of the energy density resides. <span class="hlt">Future</span> <span class="hlt">X-ray</span> observatories (XMM and AXAF) will be able to resolve the harder <span class="hlt">X-ray</span> background. For the first time we are now in a position to study the cosmological evolution of the <span class="hlt">X-ray</span> luminosity function of AGN, groups of galaxies and galaxies and simultaneously constrain their total luminosity output over cosmic time.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014SPIE.9154E..0JK','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014SPIE.9154E..0JK"><span>Monolithic CMOS imaging <span class="hlt">x-ray</span> spectrometers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kenter, Almus; Kraft, Ralph; Gauron, Thomas; Murray, Stephen S.</p> <p>2014-07-01</p> <p>The Smithsonian Astrophysical Observatory (SAO) in collaboration with SRI/Sarnoff is developing monolithic CMOS detectors optimized for <span class="hlt">x-ray</span> astronomy. The goal of this multi-year program is to produce CMOS <span class="hlt">x-ray</span> imaging spectrometers that are Fano noise limited over the 0.1-10keV energy band while incorporating the many benefits of CMOS technology. These benefits include: low power consumption, radiation "hardness", high levels of integration, and very high read rates. Small format test devices from a previous wafer fabrication run (2011-2012) have recently been back-thinned and tested for response below 1keV. These devices perform as expected in regards to dark current, read noise, spectral response and Quantum Efficiency (QE). We demonstrate that running these devices at rates ~> 1Mpix/second eliminates the need for cooling as shot noise from any dark current is greatly mitigated. The test devices were fabricated on 15μm, high resistivity custom (~30kΩ-cm) epitaxial silicon and have a 16 by 192 pixel format. They incorporate 16μm pitch, 6 Transistor Pinned Photo Diode (6TPPD) pixels which have ~40μV/electron sensitivity and a highly parallel analog CDS signal chain. Newer, improved, lower noise detectors have just been fabricated (October 2013). These new detectors are fabricated on 9μm epitaxial silicon and have a 1k by 1k format. They incorporate similar 16μm pitch, 6TPPD pixels but have ~ 50% higher sensitivity and much (3×) lower read noise. These new detectors have undergone preliminary testing for functionality in Front Illuminated (FI) form and are presently being prepared for back thinning and packaging. Monolithic CMOS devices such as these, would be ideal candidate detectors for the focal planes of Solar, <span class="hlt">planetary</span> and other space-borne <span class="hlt">x-ray</span> astronomy missions. The high through-put, low noise and excellent low energy response, provide high dynamic range and good time resolution; bright, time varying <span class="hlt">x-ray</span> features could be temporally and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1996Ap%26SS.239..177S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1996Ap%26SS.239..177S"><span>Foil <span class="hlt">X-ray</span> Mirrors</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Serlemitsos, Peter J.; Soong, Yang</p> <p>1996-09-01</p> <p>Nested thin foil reflectors have made possible light weight, inexpensive and fast grazing incidence <span class="hlt">X-ray</span> mirrors for astronomical spectroscopy over a broad band. These mirrors were developed at Goddard for the US Shuttle program and were flown on NASA's shuttleborne Astro-l mission in December 1990. Presently, the Japan/US collaborative spectroscopic mission ASCA, nearing its third year of successful operation in earth orbit, carries, four such mirrors, weighing less than 40 kg and giving total effective areas of ˜ 1200 and 420 cm2 at l and 8 keV respectively. The ˜ 420 kg observatory is the best possible example of how conical foil mirrors opened areas of research that could not have been otherwise addressed with available resources. In this paper, we will briefly review the development and performance of our first generation foil mirrors. We will also describe progress toward improving their imaging capability to prime them for use in <span class="hlt">future</span> instruments. Such a goal is highly desirable, if not necessary for this mirror technology to remain competitive for <span class="hlt">future</span> applications.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20020090904','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20020090904"><span><span class="hlt">X-Ray</span> Imaging System</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1986-01-01</p> <p>The FluoroScan Imaging System is a high resolution, low radiation device for viewing stationary or moving objects. It resulted from NASA technology developed for <span class="hlt">x-ray</span> astronomy and Goddard application to a low intensity <span class="hlt">x-ray</span> imaging scope. FlouroScan Imaging Systems, Inc, (formerly HealthMate, Inc.), a NASA licensee, further refined the FluoroScan System. It is used for examining fractures, placement of catheters, and in veterinary medicine. Its major components include an <span class="hlt">x-ray</span> generator, scintillator, visible light image intensifier and video display. It is small, light and maneuverable.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1986spin.rept...64.','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1986spin.rept...64."><span><span class="hlt">X-Ray</span> Imaging System</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p></p> <p>1986-01-01</p> <p>The FluoroScan Imaging System is a high resolution, low radiation device for viewing stationary or moving objects. It resulted from NASA technology developed for <span class="hlt">x-ray</span> astronomy and Goddard application to a low intensity <span class="hlt">x-ray</span> imaging scope. FlouroScan Imaging Systems, Inc, (formerly HealthMate, Inc.), a NASA licensee, further refined the FluoroScan System. It is used for examining fractures, placement of catheters, and in veterinary medicine. Its major components include an <span class="hlt">x-ray</span> generator, scintillator, visible light image intensifier and video display. It is small, light and maneuverable.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012PhRvL.109w3905M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012PhRvL.109w3905M"><span>Dissociative <span class="hlt">X-ray</span> Lasing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Miao, Q.; Liu, J.-C.; Ågren, H.; Rubensson, J.-E.; Gel'mukhanov, F.</p> <p>2012-12-01</p> <p><span class="hlt">X-ray</span> lasing is predicted to ensue when molecules are pumped into dissociative core-excited states by a free-electron-laser pulse. The lasing is due to the population inversion created in the neutral dissociation product, and the process features self-trapping of the <span class="hlt">x-ray</span> pulse at the gain ridge. Simulations performed for the HCl molecule pumped at the 2p1/2→6σ resonance demonstrate that the scheme can be used to create ultrashort coherent <span class="hlt">x-ray</span> pulses.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21335987','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21335987"><span><span class="hlt">X-RAY</span> MONITORING OF ULTRALUMINOUS <span class="hlt">X-RAY</span> SOURCES</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kaaret, Philip; Feng Hua</p> <p>2009-09-10</p> <p><span class="hlt">X-ray</span> monitoring observations were performed with the Swift observatory of the ultraluminous <span class="hlt">X-ray</span> sources Holmberg IX X-1, NGC 5408 X-1, and NGC 4395 X-2 and also of the nuclear <span class="hlt">X-ray</span> source in NGC 4395. Holmberg IX X-1 remains in the hard <span class="hlt">X-ray</span> spectral state as its flux varies by a factor of 7 up to a (isotropic) luminosity of 2.8 x 10{sup 40} erg s{sup -1}. This behavior may suggest an unusually massive compact object. We find excess power at periods near 60 days and 28 days in the <span class="hlt">X-ray</span> emission from Holmberg IX X-1. Additional monitoring is required to test the significance of these signals. NGC 5408 X-1 and NGC 4395 X-2 appear to remain in the soft spectral state found by Chandra and XMM with little variation in spectral hardness even as the luminosity changes by a factor of 9. We found an outburst from the nuclear source in NGC 4395 reaching an <span class="hlt">X-ray</span> luminosity of 9 x 10{sup 40} erg s{sup -1}, several times higher than any previously reported.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1993ucb..rept.....A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1993ucb..rept.....A"><span><span class="hlt">X</span> <span class="hlt">ray</span> optics for science and technology</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Attwood, David T.</p> <p>1993-12-01</p> <p>The University of California has conducted research on soft <span class="hlt">x-ray</span> physics, optics and applications thereof to the physical and life sciences. With support from the Air Force Office of Scientific Research, the University was able to develop a student research and training program. In combination with support from the DOE and, more recently, DOD's Advanced Research Projects Agency (ARPA), a world leadership research group has been established, the Center for <span class="hlt">X-ray</span> Optics (CXRO), which holds the world's record for highest resolution soft <span class="hlt">x-ray</span> microscopy (300 A); maintains leadership in biomicroscopy and spatially resolved materials studies; produces reflective optics in the soft <span class="hlt">x-ray</span> and extreme ultraviolet (EUV), which are among the best in the world; participates in an EUV lithography program which will permit the <span class="hlt">future</span> industrial evolution from visible and ultraviolet microchip patterning to EUV nanochip production; and offers one of the nation's strongest programs for student training in the emerging fields of nanostructures fabrication for materials science, quantum electronics, and biomicroscopy. A recent review article from 'Physics Today' (August 1992), which highlights some of these activities, is attached, along with the most recent annual report submitted to AFOSR, as well as other materials relevant to the AFOSR program.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..12.1446M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..12.1446M"><span>Back to the <span class="hlt">future</span>: the role of the ISS and <span class="hlt">future</span> space stations in <span class="hlt">planetary</span> exploration.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Muller, Christian; Moreau, Didier</p> <p>2010-05-01</p> <p>Space stations as stepping stones to planets appear already in the1954 Disney-von Braun anticipation TV show but the first study with a specific <span class="hlt">planetary</span> scientific objective was the ANTEUS project of 1978. This station was an evolution of SPACELAB hardware and was designed to analyse Mars samples with better equipment than the laboratory of the VIKING landers. It would have played the role of the reception facility present in the current studies of Mars sample return, after analysis, the "safe" samples would have been returned to earth by the space shuttle. This study was followed by the flights of SPACELAB and MIR. Finally after 35 years of development, the International Space Station reaches its final configuration in 2010. Recent developments of the international agreement between the space agencies indicate a life extending to 2025, it is already part of the exploration programme as its crews prepare the long cruise flights and missions to the exploration targets. It is now time to envisage also the use of this stable 350 tons spacecraft for <span class="hlt">planetary</span> and space sciences. <span class="hlt">Planetary</span> telescopes are an obvious application; the present SOLAR payload on COLUMBUS is an opportunity to use the target pointing capabilities from the ISS. The current exposure facilities are also preparing <span class="hlt">future</span> <span class="hlt">planetary</span> protection procedures. Other applications have already been previously considered as experimental collision and impact studies in both space vacuum and microgravity. <span class="hlt">Future</span> space stations at the Lagrange points could simultaneously combine unique observation platforms with an actual intermediate stepping stone to Mars.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015apra.prop....7B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015apra.prop....7B"><span><span class="hlt">X-ray</span> Line Formation by Charge Exchange</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Beiersdorfer, Peter</p> <p></p> <p>Existing <span class="hlt">X-ray</span> telescopes have revealed charge exchange to be a key astrophysical process leading to <span class="hlt">X-ray</span> emission when highly charged ions from such diverse sources as stellar winds, supernova remnants, or galactic super-winds interact with comets, <span class="hlt">planetary</span> atmospheres, or the interstellar neutral gas. Charge exchange with bare sulfur ions, for example, was proposed as an alternative explanation of the 3.5 keV <span class="hlt">X-ray</span> feature in the emission of galactic clusters that had been associated with the possible decay of sterile neutrinos. Fe XVII dominates the spectral emission of a large number of astrophysical <span class="hlt">X-ray</span> sources and, thus, is of prime diagnostic importance, as illustrated in numerous measurements by Chandra and XMM-Newton. Although immense progress has been made in laboratory measurements and spectral calculations of collisional plasmas since the launch of these <span class="hlt">X-ray</span> observatories, model calculations of the Fe XVII <span class="hlt">X-ray</span> spectrum still do not yield agreement with astrophysical observations that is completely satisfactory. As a result, charge exchange has been invoked as an alternative explanation for the poor agreement between models and observations. Theoretically, line formation by charge exchange, however, is still only poorly understood both in the case of the rather 'simple'K-shell spectra of hydrogenlike or heliumlike ions, such as Fe XXV and Fe XXVI, and the more complex L-shell spectra of neonlike ions such as Fe XVII. Experimentally, there is only a small set of laboratory measurements involving <span class="hlt">X-rays</span> from K-shell ions, and almost no measurements of the charge exchange produced <span class="hlt">X-ray</span> emission involving L-shell ions. Moreover, the existing laboratory measurements have focused mostly on charge exchange processes pertaining to the solar wind interacting with complex (molecular) gases in cometary and <span class="hlt">planetary</span> atmospheres. By contrast, we propose here to perform <span class="hlt">X-ray</span> measurements pertaining to astrophysical exchange processes dominated by atomic</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20050236996&hterms=arisen&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Darisen','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20050236996&hterms=arisen&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Darisen"><span>Chandra <span class="hlt">X-Ray</span> Observatory Observations of the Jovian System</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Elsner, R. F.; Bhardwaj, A.; Gladstone, R.; Waite, J. H.; Ford, P.; Branduari-Raymont, G.</p> <p>2005-01-01</p> <p>Chandra <span class="hlt">X-ray</span> Observatory (CXO) and XMM-Newton observations of <span class="hlt">x-rays</span> from the Jovian system have answered questions that arose from early observations with the Einstein and Rosat <span class="hlt">X-ray</span> Observatories, but in the process of vastly increasing our knowledge of <span class="hlt">x-ray</span> emission from Jupiter and its environs they have also raised new questions and point to new opportunities for <span class="hlt">future</span> studies. We will review recent <span class="hlt">x-ray</span> results on the Jovian system, from the point of view of the CXO, and discuss various questions that have arisen in the course of our studies. We will discuss prospects for more observations in the immediate <span class="hlt">future</span>, and how they might address open questions. Finally we will briefly describe ways in which an imaging <span class="hlt">x-ray</span> spectrometer in the vicinity of the Jovian system could provide a wealth of data and results concerning Jupiter's <span class="hlt">x-ray</span> auroral and disk emission, elemental abundance measurements for the Galilean moons, and detailed studies of <span class="hlt">x-ray</span> emission from the Io Plasma Torus.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMSM51H..08C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMSM51H..08C"><span>Soft <span class="hlt">X-ray</span> and ENA imaging of the Earth's dayside magnetosphere : OpenGGCM modeling results</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Connor, H. K.; Sibeck, D. G.; Collier, M. R.; Kuntz, K. D.; Raeder, J.</p> <p>2014-12-01</p> <p>Charged ions and neutral atoms exchange electrons in many space plasma venues. Soft <span class="hlt">X-rays</span> are emitted when highly charged solar wind ions, such as C6+, O7+, and Fe13+, interact with Hydrogen and Helium atoms. Energetic Neutral Atoms (ENAs) are produced when solar wind protons encounter neutral atoms. Consequently ENA and soft <span class="hlt">x-ray</span> images can be a powerful technique to probe remotely the plasma and neutral density structures created when the solar wind interacts with <span class="hlt">planetary</span> exospheres, such as those at the Earth, Moon, Mars, Venus, and comets. Here, we use the OpenGGCM global magnetosphere-ionosphere MHD model and the Hodges model for the Earth's exosphere to simulate both soft <span class="hlt">X-ray</span> and ENA images of Earth's dayside cusps and magnetosheath in preparation for <span class="hlt">future</span> mission planning. We consider several solar wind and IMF scenarios, such as a sudden increase in the solar wind dynamic pressure and southward IMF turning. We then predict the time-dependent variations in <span class="hlt">X-Ray</span> and ENA images that would be observed by spacecraft far outside the magnetosphere. As expected, strong signals appear near to and define the positions of the bow shock, magnetopause, and cusps. The soft <span class="hlt">X-ray</span> imager observes changes in the dayside system nearly instantaneously, while the ENA imager measures the changes later due to the finite travel time of ENAs from the dayside systems to the spacecraft location.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://medlineplus.gov/ency/article/003807.htm','NIH-MEDLINEPLUS'); return false;" href="https://medlineplus.gov/ency/article/003807.htm"><span>Lumbosacral spine <span class="hlt">x-ray</span></span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... should be taken before children receive <span class="hlt">x-rays</span>. Considerations There are some back problems that an x- ... imaging for low back pain: advice for high-value health care from the American College of Physicians. ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/873324','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/873324"><span>Miniature <span class="hlt">x-ray</span> source</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Trebes, James E.; Bell, Perry M.; Robinson, Ronald B.</p> <p>2000-01-01</p> <p>A miniature <span class="hlt">x-ray</span> source utilizing a hot filament cathode. The source has a millimeter scale size and is capable of producing broad spectrum <span class="hlt">x-ray</span> emission over a wide range of <span class="hlt">x-ray</span> energies. The miniature source consists of a compact vacuum tube assembly containing the hot filament cathode, an anode, a high voltage feedthru for delivering high voltage to the cathode, a getter for maintaining high vacuum, a connector for initial vacuum pump down and crimp-off, and a high voltage connection for attaching a compact high voltage cable to the high voltage feedthru. At least a portion of the vacuum tube wall is fabricated from highly <span class="hlt">x-ray</span> transparent materials, such as sapphire, diamond, or boron nitride.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/AD0706078','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/AD0706078"><span>CELESTIAL <span class="hlt">X-RAY</span> SOURCES.</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p></p> <p>sources, (4) the physical conditions in the pulsating <span class="hlt">x-ray</span> source in the Crab Nebula , and (5) miscellaneous related topics. A bibliography of all work performed under the contract is given. (Author)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010NaPho...4..840S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010NaPho...4..840S"><span>Nanoscale <span class="hlt">X-ray</span> imaging</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sakdinawat, Anne; Attwood, David</p> <p>2010-12-01</p> <p>Recent years have seen significant progress in the field of soft- and hard-<span class="hlt">X-ray</span> microscopy, both technically, through developments in source, optics and imaging methodologies, and also scientifically, through a wide range of applications. While an ever-growing community is pursuing the extensive applications of today's available <span class="hlt">X-ray</span> tools, other groups are investigating improvements in techniques, including new optics, higher spatial resolutions, brighter compact sources and shorter-duration <span class="hlt">X-ray</span> pulses. This Review covers recent work in the development of direct image-forming <span class="hlt">X-ray</span> microscopy techniques and the relevant applications, including three-dimensional biological tomography, dynamical processes in magnetic nanostructures, chemical speciation studies, industrial applications related to solar cells and batteries, and studies of archaeological materials and historical works of art.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://kidshealth.org/en/parents/xray-pelvis.html','NIH-MEDLINEPLUS'); return false;" href="http://kidshealth.org/en/parents/xray-pelvis.html"><span><span class="hlt">X-Ray</span> Exam: Pelvis</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... KidsHealth in the Classroom What Other Parents Are Reading Your Child's Development (Birth to 3 Years) Feeding ... radiologist (a doctor who is specially trained in reading and interpreting <span class="hlt">X-ray</span> images). The radiologist will ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://kidshealth.org/en/parents/xray-forearm.html','NIH-MEDLINEPLUS'); return false;" href="http://kidshealth.org/en/parents/xray-forearm.html"><span><span class="hlt">X-Ray</span> Exam: Forearm</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... KidsHealth in the Classroom What Other Parents Are Reading Your Child's Development (Birth to 3 Years) Feeding ... a radiologist (a doctor who's specially trained in reading and interpreting <span class="hlt">X-ray</span> images). The radiologist will ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://kidshealth.org/en/parents/xray-finger.html','NIH-MEDLINEPLUS'); return false;" href="http://kidshealth.org/en/parents/xray-finger.html"><span><span class="hlt">X-Ray</span> Exam: Finger</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... KidsHealth in the Classroom What Other Parents Are Reading Your Child's Development (Birth to 3 Years) Feeding ... Results A radiologist, a doctor specially trained in reading and interpreting <span class="hlt">X-ray</span> images, will look at ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840025694','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840025694"><span>Imaging <span class="hlt">X-ray</span> spectrometer</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Grant, P. A.; Jackson, J. W., Jr.; Alcorn, G. E.; Marshall, F. E. (Inventor)</p> <p>1984-01-01</p> <p>An <span class="hlt">X-ray</span> spectrometer for providing imaging and energy resolution of an <span class="hlt">X-ray</span> source is described. This spectrometer is comprised of a thick silicon wafer having an embedded matrix or grid of aluminum completely through the wafer fabricated, for example, by thermal migration. The aluminum matrix defines the walls of a rectangular array of silicon <span class="hlt">X-ray</span> detector cells or pixels. A thermally diffused aluminum electrode is also formed centrally through each of the silicon cells with biasing means being connected to the aluminum cell walls and causes lateral charge carrier depletion between the cell walls so that incident <span class="hlt">X-ray</span> energy causes a photoelectric reaction within the silicon producing collectible charge carriers in the form of electrons which are collected and used for imaging.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22496167','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22496167"><span><span class="hlt">X-ray</span> microtomographic scanners</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Syryamkin, V. I. Klestov, S. A.</p> <p>2015-11-17</p> <p>The article studies the operating procedures of an <span class="hlt">X-ray</span> microtomographic scanner and the module of reconstruction and analysis 3D-image of a test sample in particular. An algorithm for 3D-image reconstruction based on image shadow projections and mathematical methods of the processing are described. Chapter 1 describes the basic principles of <span class="hlt">X-ray</span> tomography and general procedures of the device developed. Chapters 2 and 3 are devoted to the problem of resources saving by the system during the <span class="hlt">X-ray</span> tomography procedure, which is achieved by preprocessing of the initial shadow projections. Preprocessing includes background noise removing from the images, which reduces the amount of shadow projections in general and increases the efficiency of the group shadow projections compression. In conclusion, the main applications of <span class="hlt">X-ray</span> tomography are presented.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.radiologyinfo.org/en/info.cfm?pg=bonerad','NIH-MEDLINEPLUS'); return false;" href="http://www.radiologyinfo.org/en/info.cfm?pg=bonerad"><span>Bone <span class="hlt">X-Ray</span> (Radiography)</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... have very controlled <span class="hlt">x-ray</span> beams and dose control methods to minimize stray (scatter) radiation. This ensures that those parts of a patient's body not being imaged receive minimal radiation exposure. top ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.radiologyinfo.org/en/info.cfm?pg=abdominrad','NIH-MEDLINEPLUS'); return false;" href="http://www.radiologyinfo.org/en/info.cfm?pg=abdominrad"><span>Abdomen <span class="hlt">X-Ray</span> (Radiography)</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... have very controlled <span class="hlt">x-ray</span> beams and dose control methods to minimize stray (scatter) radiation. This ensures that those parts of a patient's body not being imaged receive minimal radiation exposure. top ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19800022779','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19800022779"><span><span class="hlt">X-ray</span> astronomical spectroscopy</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Holt, S. S.</p> <p>1980-01-01</p> <p>The current status of the <span class="hlt">X-ray</span> spectroscopy of celestial <span class="hlt">X-ray</span> sources, ranging from nearby stars to distant quasars, is reviewed. Particular emphasis is placed on the role of such spectroscopy as a useful and unique tool in the elucidation of the physical parameters of the sources. The spectroscopic analysis of degenerate and nondegenerate stellar systems, galactic clusters and active galactic nuclei, and supernova remnants is discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1993AeEn...13Q..17.','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1993AeEn...13Q..17."><span><span class="hlt">X-ray</span> computed tomography</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p></p> <p>1993-05-01</p> <p>The primary advantage of the <span class="hlt">X-ray</span> computed tomography (XRCT) NDE method is that features are not superposed in the image, thereby rendering them easier to interpret than radiographic projection images. Industrial XRCT systems, unlike medical diagnostic systems, have no size and dosage constraints; they are accordingly used for systems from the scale of gas turbine blades, with hundreds-of-kV energies, to those of the scale of ICBMs, requiring MV-level <span class="hlt">X-ray</span> energies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1250440','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1250440"><span>Electromechanical <span class="hlt">x-ray</span> generator</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Watson, Scott A; Platts, David; Sorensen, Eric B</p> <p>2016-05-03</p> <p>An electro-mechanical <span class="hlt">x-ray</span> generator configured to obtain high-energy operation with favorable energy-weight scaling. The electro-mechanical <span class="hlt">x-ray</span> generator may include a pair of capacitor plates. The capacitor plates may be charged to a predefined voltage and may be separated to generate higher voltages on the order of hundreds of kV in the AK gap. The high voltage may be generated in a vacuum tube.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/AD1001591','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/AD1001591"><span><span class="hlt">X-ray</span> Sensitive Material</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2015-12-01</p> <p>The research resulted in a composite material that holds a quasi-permanent electric charge and rapidly discharges the electric charge upon <span class="hlt">X-ray</span>...temperature extremes encountered during processing and potential application. (U) The result of these efforts was a composite material that would hold a...quasi-permanent electric charge and rapidly discharge the electric charge upon <span class="hlt">X-ray</span> exposure. The composite material combined the properties of an</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20020044136','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20020044136"><span>High Resolution <span class="hlt">X-ray</span> Imaging</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cash, Webster</p> <p>2002-01-01</p> <p>NAG5-5020 covered a period of 7.5 years during which a great deal of progress was made in <span class="hlt">x-ray</span> optical techniques under this grant. We survived peer review numerous times during the effort to keep the grant going. In 1994, when the grant started we were actively pursuing the application of spherical mirrors to improving <span class="hlt">x-ray</span> telescopes. We had found that <span class="hlt">x-ray</span> detectors were becoming rapidly more sophisticated and affordable, but that <span class="hlt">x-ray</span> telescopes were only being improved through the intense application of money within the AXAF program. Clearly new techniques for the <span class="hlt">future</span> were needed. We were successful in developing and testing at the HELSTF facility in New Mexico a four reflection coma-corrected telescope made from spheres. We were able to demonstrate 0.3 arcsecond resolution, almost to the diffraction limit of the system. The community as a whole was, at that time, not particularly interested in looking past AXAF (Chandra) and the effort needed to evolve. Since we had reached the diffraction limit using non-Wolter optics we then decided to see if we could build an <span class="hlt">x-ray</span> interferometer in the laboratory. In the lab the potential for improved resolution was substantial. If synthetic aperture telescopes could be built in space, then orders of magnitude improvement would become feasible. In 1998 NASA, under the direction of Dr Nick White of Goddard, started a study to assess the potential and feasibility of <span class="hlt">x-ray</span> interferometry in space. My work became of central interest to the committee because it indicated that such was possible. In early 1999 we had the breakthrough that allowed us build a practical interferometer. By using flats and hooking up with the Marshall Space Flight Center facilities we were able to demonstrate fringes at 1.25keV on a one millimeter baseline. This actual laboratory demonstration provided the solid proof of concept that NASA needed. As the year progressed the <span class="hlt">future</span> of <span class="hlt">x-ray</span> astronomy jelled around the Maxim program. Maxim is a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6921033','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6921033"><span>Tokamak <span class="hlt">x</span> <span class="hlt">ray</span> diagnostic instrumentation</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hill, K.W.; Beiersdorfer, P.; Bitter, M.; Fredrickson, E.; Von Goeler, S.; Hsuan, H.; Johnson, L.C.; Liew, S.L.; McGuire, K.; Pare, V.</p> <p>1987-01-01</p> <p>Three classes of <span class="hlt">x-ray</span> diagnostic instruments enable measurement of a variety of tokamak physics parameters from different features of the <span class="hlt">x-ray</span> emission spectrum. (1) The soft <span class="hlt">x-ray</span> (1 to 50 keV) pulse-height-analysis (PHA) diagnostic measures impurity concentrations from characteristic line intensities and the continuum enhancement, and measures the electron temperature from the continuum slope. (2) The Bragg <span class="hlt">x-ray</span> crystal spectrometer (XCS) measures the ion temperature and neutral-beam-induced toroidal rotation velocity from the Doppler broadening and wavelength shift, respectively, of spectral lines of medium-Z impurity ions. Impurity charge state distributions, precise wavelengths, and inner-shell excitation and recombination rates can also be studied. <span class="hlt">X</span> <span class="hlt">rays</span> are diffracted and focused by a bent crystal onto a position-sensitive detector. The spectral resolving power E/..delta..E is greater than 10/sup 4/ and time resolution is 10 ms. (3) The <span class="hlt">x-ray</span> imaging system (XIS) measures the spatial structure of rapid fluctuations (0.1 to 100 kHZ) providing information on MHD phenomena, impurity transport rates, toroidal rotation velocity, plasma position, and the electron temperature profile. It uses an array of silicon surface-barrier diodes which view different chords of the plasma through a common slot aperture and operate in current (as opposed to counting) mode. The effectiveness of shields to protect detectors from fusion-neutron radiation effects has been studied both theoretically and experimentally.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19850020598','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19850020598"><span>Cosmic <span class="hlt">X-ray</span> physics</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mccammon, D.; Cox, D. P.; Kraushaar, W. L.; Sanders, W. T.</p> <p>1985-01-01</p> <p>A progress report of research activities carried out in the area of cosmic <span class="hlt">X-ray</span> physics is presented. The Diffuse <span class="hlt">X-ray</span> Spectrometer DXS which has been flown twice as a rocket payload is described. The observation times proved to be too small for meaningful <span class="hlt">X-ray</span> data to be obtained. Data collection and reduction activities from the Ultra-Soft <span class="hlt">X-ray</span> background (UXT) instrument are described. UXT consists of three mechanically-collimated <span class="hlt">X-ray</span> gas proportional counters with window/filter combinations which allow measurements in three energy bands, Be (80-110 eV), B (90-187 eV), and O (e84-532 eV). The Be band measurements provide an important constraint on local absorption of <span class="hlt">X-rays</span> from the hot component of the local interstellar medium. Work has also continued on the development of a calorimetric detector for high-resolution spectroscopy in the 0.1 keV - 8keV energy range.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.fda.gov/Radiation-EmittingProducts/RadiationEmittingProductsandProcedures/MedicalImaging/MedicalX-Rays/ucm142632.htm','NIH-MEDLINEPLUS'); return false;" href="https://www.fda.gov/Radiation-EmittingProducts/RadiationEmittingProductsandProcedures/MedicalImaging/MedicalX-Rays/ucm142632.htm"><span><span class="hlt">X-Rays</span>, Pregnancy and You</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... and Procedures Medical Imaging Medical <span class="hlt">X-ray</span> Imaging <span class="hlt">X-Rays</span>, Pregnancy and You Share Tweet Linkedin Pin it ... the decision with your doctor. What Kind of <span class="hlt">X-Rays</span> Can Affect the Unborn Child? During most x- ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110023086','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110023086"><span>Traverse Planning Experiments for <span class="hlt">Future</span> <span class="hlt">Planetary</span> Surface Exploration</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hoffman, S. J.; Voels, S. A.; Mueller, R. P.; Lee, P. C.</p> <p>2011-01-01</p> <p>This paper describes the results of a recent (July-August 2010 and July 2011) <span class="hlt">planetary</span> surface traverse planning experiment. The purpose of this experiment was to gather data relevant to robotically repositioning surface assets used for <span class="hlt">planetary</span> surface exploration. This is a scenario currently being considered for <span class="hlt">future</span> human exploration missions to the Moon and Mars. The specific scenario selected was a robotic traverse on the lunar surface from an outpost at Shackleton Crater to the Malapert Massif. As these are exploration scenarios, the route will not have been previously traversed and the only pre-traverse data sets available will be remote (orbital) observations. Devon Island was selected as an analog location where a traverse route of significant length could be planned and then traveled. During the first half of 2010, a team of engineers and scientists who had never been to Devon Island used remote sensing data comparable to that which is likely to be available for the Malapert region (eg., 2-meter/pixel imagery, 10-meter interval topographic maps and associated digital elevation models, etc.) to plan a 17-kilometer (km) traverse. Surface-level imagery data was then gathered on-site that was provided to the planning team. This team then assessed whether the route was actually traversable or not. Lessons learned during the 2010 experiment were then used in a second experiment in 2011 for which a much longer traverse (85 km) was planned and additional surface-level imagery different from that gathered in 2010 was obtained for a comparative analysis. This paper will describe the route planning techniques used, the data sets available to the route planners and the lessons learned from the two traverses planned and carried out on Devon Island.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016IPNPR.207B...1V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016IPNPR.207B...1V"><span>A Novel Rotating-Wave <span class="hlt">X-Ray</span> Source for Analysis of the Martian Landscape</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Velazco, J. E.; Taylor, M.; Liu, Y.; Hodyss, R.; Allwood, A.</p> <p>2016-11-01</p> <p>In this article, we present analysis and computer simulations for a new accelerator concept that we are proposing for exploration of various <span class="hlt">planetary</span> surfaces, including the Martian landscape. The rotating-wave accelerator (RWA) uses rotating-wave fields and an external magnetic field to produce acceleration of a low-energy electron beam to high velocities. <span class="hlt">X-rays</span> are produced by the electrons upon impinging on a suitable target. A linear analysis of the accelerating process is presented as well as computer simulations. These studies show that the RWA can successfully achieve 200-keV <span class="hlt">X-rays</span>; energy that is ideally suited for <span class="hlt">X-ray</span> analysis on Mars and other <span class="hlt">planetary</span> missions. The RWA development will enable a new generation of very compact, power-efficient imaging and analytical instruments capable of producing high-energy <span class="hlt">X-rays</span> for standoff <span class="hlt">planetary</span> surface <span class="hlt">X-ray</span> analysis such as fluorescence and tomography.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012PhPl...19g2703H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012PhPl...19g2703H"><span>Burning plasmas with ultrashort soft-<span class="hlt">x-ray</span> flashing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hu, S. X.; Goncharov, V. N.; Skupsky, S.</p> <p>2012-07-01</p> <p>Fast ignition with narrow-band coherent <span class="hlt">x-ray</span> pulses has been revisited for cryogenic deuterium-tritium (DT) plasma conditions achieved on the OMEGA Laser System. In contrast to using hard-<span class="hlt">x-rays</span> (hv = 3-6 keV) proposed in the original <span class="hlt">x-ray</span> fast-ignition proposal, we find that soft-<span class="hlt">x-ray</span> sources with hv ≈ 500 eV photons can be suitable for igniting the dense DT-plasmas achieved on OMEGA. Two-dimensional radiation-hydrodynamics simulations have identified the break-even conditions for realizing such a "hybrid" ignition scheme (direct-drive compression with soft-<span class="hlt">x-ray</span> heating) with 50-μm-offset targets: ˜10 ps soft-<span class="hlt">x-ray</span> pulse (hv ≈ 500 eV) with a total energy of 500-1000 J to be focused into a 10 μm spot-size. A variety of <span class="hlt">x-ray</span> pulse parameters have also been investigated for optimization. It is noted that an order of magnitude increase in neutron yield has been predicted even with <span class="hlt">x-ray</span> energy as low as ˜50 J. Scaling this idea to a 1 MJ large-scale target, a gain above ˜30 can be reached with the same soft-<span class="hlt">x-ray</span> pulse at 1.65 kJ energy. Even though such energetic <span class="hlt">x-ray</span> sources do not currently exist, we hope that the proposed ignition scheme may stimulate efforts on generating powerful soft-<span class="hlt">x-ray</span> sources in the near <span class="hlt">future</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22072586','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22072586"><span>Burning plasmas with ultrashort soft-<span class="hlt">x-ray</span> flashing</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hu, S. X.; Goncharov, V. N.; Skupsky, S.</p> <p>2012-07-15</p> <p>Fast ignition with narrow-band coherent <span class="hlt">x-ray</span> pulses has been revisited for cryogenic deuterium-tritium (DT) plasma conditions achieved on the OMEGA Laser System. In contrast to using hard-<span class="hlt">x-rays</span> (hv = 3-6 keV) proposed in the original <span class="hlt">x-ray</span> fast-ignition proposal, we find that soft-<span class="hlt">x-ray</span> sources with hv Almost-Equal-To 500 eV photons can be suitable for igniting the dense DT-plasmas achieved on OMEGA. Two-dimensional radiation-hydrodynamics simulations have identified the break-even conditions for realizing such a 'hybrid' ignition scheme (direct-drive compression with soft-<span class="hlt">x-ray</span> heating) with 50-{mu}m-offset targets: {approx}10 ps soft-<span class="hlt">x-ray</span> pulse (hv Almost-Equal-To 500 eV) with a total energy of 500-1000 J to be focused into a 10 {mu}m spot-size. A variety of <span class="hlt">x-ray</span> pulse parameters have also been investigated for optimization. It is noted that an order of magnitude increase in neutron yield has been predicted even with <span class="hlt">x-ray</span> energy as low as {approx}50 J. Scaling this idea to a 1 MJ large-scale target, a gain above {approx}30 can be reached with the same soft-<span class="hlt">x-ray</span> pulse at 1.65 kJ energy. Even though such energetic <span class="hlt">x-ray</span> sources do not currently exist, we hope that the proposed ignition scheme may stimulate efforts on generating powerful soft-<span class="hlt">x-ray</span> sources in the near <span class="hlt">future</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1992SPIE.1744..196I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1992SPIE.1744..196I"><span>Imaging of <span class="hlt">X</span> <span class="hlt">rays</span> for magnetospheric investigations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Imhof, William L.; Voss, Henry D.; Datlowe, Dayton W.</p> <p>1992-06-01</p> <p>Precipitation of energetic electrons from the magnetosphere into the auroral zone produces <span class="hlt">x</span>- <span class="hlt">ray</span> bremsstrahlung. Although in-situ electron spectrometers can provide detailed information at the point of observation, only <span class="hlt">x-ray</span> imagers can provide large scale maps of the 1 to 300 keV energy electron precipitation. <span class="hlt">X-ray</span> imaging provides complete day and night coverage of the electron energy spectra at each position. Early <span class="hlt">x-ray</span> images, such as those obtained from 1979 - 1983, served to demonstrate the importance of narrow elongated arcs of energetic electron precipitation in the auroral zone. They also characterized the spectral parameters and precipitation rates required for understanding source and loss mechanisms in the magnetosphere, but they were limited in field of view and to one map for each pass over the emitting regions. The Magnetospheric Atmospheric <span class="hlt">X-ray</span> Imaging Experiment (MAXIE), soon to be launched on a TIROS satellite, will make time-space mappings by scanning a 16 pixel pinhole camera. These data will distinguish intensity variations of a fixed auroral feature from motion of a steadily radiating features. However, the spatial deconvolution is complex and features stay in the field of view for only approximately 10 minutes. These problems will be resolved by a high altitude (approximately 9 Re) imaging spectrometer PIXIE on the ISTP/GGS Polar Satellite to be launched in 1994. PIXIE's position sensitive proportional counter will continuously image the entire auroral zone for periods of hours. The resulting images will be important for understanding how the electrons are accelerated in the magnetosphere and why and where they precipitate into the atmosphere. <span class="hlt">Future</span> needs and plans for next generation imagers will be discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20100035720','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20100035720"><span>High-Resolution <span class="hlt">X-Ray</span> Telescopes</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>ODell, Stephen L.; Brissenden, Roger J.; Davis, William; Elsner, Ronald F.; Elvis, Martin; Freeman, Mark; Gaetz, Terry; Gorenstein, Paul; Gubarev, Mikhail V.</p> <p>2010-01-01</p> <p>Fundamental needs for <span class="hlt">future</span> <span class="hlt">x-ray</span> telescopes: a) Sharp images => excellent angular resolution. b) High throughput => large aperture areas. Generation-X optics technical challenges: a) High resolution => precision mirrors & alignment. b) Large apertures => lots of lightweight mirrors. Innovation needed for technical readiness: a) 4 top-level error terms contribute to image size. b) There are approaches to controlling those errors. Innovation needed for manufacturing readiness. Programmatic issues are comparably challenging.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/10187184','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/10187184"><span>Center for <span class="hlt">X-Ray</span> Optics, 1992</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Not Available</p> <p>1993-08-01</p> <p>This report discusses the following topics: Center for <span class="hlt">X-Ray</span> Optics; Soft <span class="hlt">X-Ray</span> Imaging wit Zone Plate Lenses; Biological <span class="hlt">X-Ray</span> microscopy; Extreme Ultraviolet Lithography for Nanoelectronic Pattern Transfer; Multilayer Reflective Optics; EUV/Soft <span class="hlt">X-ray</span> Reflectometer; Photoemission Microscopy with Reflective Optics; Spectroscopy with Soft <span class="hlt">X-Rays</span>; Hard <span class="hlt">X-Ray</span> Microprobe; Coronary Angiography; and Atomic Scattering Factors.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25889609','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25889609"><span>Implications of <span class="hlt">X-ray</span> tube parameter deviations in <span class="hlt">X-ray</span> reference fields.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Behnke, B; Hupe, O; Ambrosi, P</p> <p>2016-02-01</p> <p>For the purpose of radiation protection, ICRU Report 57/ICRP Publication 74 provides a list of monoenergetic conversion coefficients to be used with, among others, photon reference fields generated with <span class="hlt">X-ray</span> tubes. A comprehensive definition of these photon reference fields can be found in international standard ISO 4037; however, it lacks thorough indication of the allowed deviations of essential parameters that influence these <span class="hlt">X-ray</span> reference fields. These parameters are the high-voltage tube potential, the thickness of the beryllium window and the purity and thickness of the filter materials used to create different radiation qualities. Small variations of these parameters can lead to significant changes in the created <span class="hlt">X-ray</span> spectra and, hence, the spectra-dependent conversion coefficients for phantom-related radiation-protection quantities. This can lead to situations in which the conversion coefficients listed in ISO 4037 cannot be used, resulting in time-consuming spectrometry measurements. In this work, the impact on the resulting conversion coefficients is investigated using a simplified mathematical approximation model. The findings are validated with an independent <span class="hlt">X-ray</span> spectra calculation programme. As a result, well-founded upper limit values on the allowed deviations of the essential <span class="hlt">X-ray</span> tube parameters are proposed to be used in a <span class="hlt">future</span> revision of ISO 4037. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4884881','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4884881"><span>Implications of <span class="hlt">X-ray</span> tube parameter deviations in <span class="hlt">X-ray</span> reference fields</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Behnke, B.; Hupe, O.; Ambrosi, P.</p> <p>2016-01-01</p> <p>For the purpose of radiation protection, ICRU Report 57/ICRP Publication 74 provides a list of monoenergetic conversion coefficients to be used with, among others, photon reference fields generated with <span class="hlt">X-ray</span> tubes. A comprehensive definition of these photon reference fields can be found in international standard ISO 4037; however, it lacks thorough indication of the allowed deviations of essential parameters that influence these <span class="hlt">X-ray</span> reference fields. These parameters are the high-voltage tube potential, the thickness of the beryllium window and the purity and thickness of the filter materials used to create different radiation qualities. Small variations of these parameters can lead to significant changes in the created <span class="hlt">X-ray</span> spectra and, hence, the spectra-dependent conversion coefficients for phantom-related radiation-protection quantities. This can lead to situations in which the conversion coefficients listed in ISO 4037 cannot be used, resulting in time-consuming spectrometry measurements. In this work, the impact on the resulting conversion coefficients is investigated using a simplified mathematical approximation model. The findings are validated with an independent <span class="hlt">X-ray</span> spectra calculation programme. As a result, well-founded upper limit values on the allowed deviations of the essential <span class="hlt">X-ray</span> tube parameters are proposed to be used in a <span class="hlt">future</span> revision of ISO 4037. PMID:25889609</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4934190','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4934190"><span><span class="hlt">X-ray</span> Photon Counting and Two-Color <span class="hlt">X-ray</span> Imaging Using Indirect Detection</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Dierickx, Bart; Yao, Qiang; Witvrouwen, Nick; Uwaerts, Dirk; Vandewiele, Stijn; Gao, Peng</p> <p>2016-01-01</p> <p>In this paper, we report on the design and performance of a 1 cm2, 90 × 92-pixel image sensor. It is made <span class="hlt">X-ray</span> sensitive by the use of a scintillator. Its pixels have a charge packet counting circuit topology with two channels, each realizing a different charge packet size threshold and analog domain event counting. Here, the sensor’s performance was measured in setups representative of a medical <span class="hlt">X-ray</span> environment. Further, two-energy-level photon counting performance is demonstrated, and its capabilities and limitations are documented. We then provide an outlook on <span class="hlt">future</span> improvements. PMID:27240362</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/842053','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/842053"><span>Methods of Attosecond <span class="hlt">X-Ray</span> Pulse Generation</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Zholents, Alexander</p> <p>2005-05-08</p> <p>We review several proposals for generation of solitary attosecond pulses using two types of free electron lasers which are envisioned as <span class="hlt">future</span> light sources for studies of ultra-fast dynamics using soft and hard <span class="hlt">x-rays</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20050180713&hterms=x-rays&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dx-rays','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20050180713&hterms=x-rays&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dx-rays"><span>A Comparative View of <span class="hlt">X-rays</span> from the Solar System</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bhardwaj, Anil; Elsner, Ron; Gladstone, Randy; Cravens, Tom; Waite, Hunter; Branduardi-Raymont, Graziella; Ostgaard, Nikolai; Dennerl, Konrad; Lisse, Carey; Kharchenko, Vasili</p> <p>2005-01-01</p> <p>With the advent of sophisticated <span class="hlt">X-ray</span> observatories, viz., Chandra and XMM-Newton, the field of <span class="hlt">planetary</span> <span class="hlt">X-ray</span> astronomy is advancing at a faster pace. Several new solar system objects are now know to shine in <span class="hlt">X-rays</span> at energies generally below 2 keV. Jupiter, Saturn, and Earth, all three magnetized planets, have been observed by Chandra and XMM-Newton. At Jupiter, both auroral and non-auroral disk <span class="hlt">X-ray</span> emissions have been observed. The first soft <span class="hlt">X-ray</span> observation of Earth's aurora by Chandra shows that it is highly variable. <span class="hlt">X-rays</span> have been detected from Saturn's disk, but no convincing evidence of <span class="hlt">X-ray</span> aurora has been seen. Several comets have been observed in <span class="hlt">X-rays</span> by Chandra and XMM-Newton. Cometary <span class="hlt">X-rays</span> are produced due to change exchange of solar wind ions with cold cometary neutrals. Soft <span class="hlt">X-rays</span> have also been observed from Venus, Mars, Moon, Io, Europa, Io plasma torus, and heliosphere. The non-auroral <span class="hlt">X-ray</span> emissions from Jupiter, Saturn, and Earth, and those from sunlit disk of Mars, Venus, and Moon are produced due to scattering of solar <span class="hlt">X-rays</span>. The spectral characteristics of <span class="hlt">X-ray</span> emission from comets, heliosphere, darkside of Moon, and Martian halo are quite similar, but they appear to be quite different from those of Jovian auroral <span class="hlt">X-rays</span>. The <span class="hlt">X</span>- <span class="hlt">ray</span> aurora on Earth is generated by electron bremsstrahlung and on Jupiter by precipitation of highly-ionized energetic heavy ions. In this paper we will present a comparative overview of <span class="hlt">X-ray</span> emission from different solar system objects and make an attempt to synthesize a coherent picture.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20050180713&hterms=nikolai&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dnikolai%2B2','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20050180713&hterms=nikolai&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dnikolai%2B2"><span>A Comparative View of <span class="hlt">X-rays</span> from the Solar System</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bhardwaj, Anil; Elsner, Ron; Gladstone, Randy; Cravens, Tom; Waite, Hunter; Branduardi-Raymont, Graziella; Ostgaard, Nikolai; Dennerl, Konrad; Lisse, Carey; Kharchenko, Vasili</p> <p>2005-01-01</p> <p>With the advent of sophisticated <span class="hlt">X-ray</span> observatories, viz., Chandra and XMM-Newton, the field of <span class="hlt">planetary</span> <span class="hlt">X-ray</span> astronomy is advancing at a faster pace. Several new solar system objects are now know to shine in <span class="hlt">X-rays</span> at energies generally below 2 keV. Jupiter, Saturn, and Earth, all three magnetized planets, have been observed by Chandra and XMM-Newton. At Jupiter, both auroral and non-auroral disk <span class="hlt">X-ray</span> emissions have been observed. The first soft <span class="hlt">X-ray</span> observation of Earth's aurora by Chandra shows that it is highly variable. <span class="hlt">X-rays</span> have been detected from Saturn's disk, but no convincing evidence of <span class="hlt">X-ray</span> aurora has been seen. Several comets have been observed in <span class="hlt">X-rays</span> by Chandra and XMM-Newton. Cometary <span class="hlt">X-rays</span> are produced due to change exchange of solar wind ions with cold cometary neutrals. Soft <span class="hlt">X-rays</span> have also been observed from Venus, Mars, Moon, Io, Europa, Io plasma torus, and heliosphere. The non-auroral <span class="hlt">X-ray</span> emissions from Jupiter, Saturn, and Earth, and those from sunlit disk of Mars, Venus, and Moon are produced due to scattering of solar <span class="hlt">X-rays</span>. The spectral characteristics of <span class="hlt">X-ray</span> emission from comets, heliosphere, darkside of Moon, and Martian halo are quite similar, but they appear to be quite different from those of Jovian auroral <span class="hlt">X-rays</span>. The <span class="hlt">X</span>- <span class="hlt">ray</span> aurora on Earth is generated by electron bremsstrahlung and on Jupiter by precipitation of highly-ionized energetic heavy ions. In this paper we will present a comparative overview of <span class="hlt">X-ray</span> emission from different solar system objects and make an attempt to synthesize a coherent picture.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1983STIN...8326058B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1983STIN...8326058B"><span><span class="hlt">X-ray</span> spectroscopy to determine line coincidences</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Burkhalter, P. G.; Charatis, G.; Rockett, P.</p> <p>1983-01-01</p> <p><span class="hlt">X-ray</span> spectroscopy in the 12-15 A region of L-shell lines from selected transition elements was performed in a joint Naval Research Laboratory - KMS Fusion, Inc. experiment. The accurate wavelengths determined in this work will be utilized in selecting potential pumping candidates in <span class="hlt">future</span> <span class="hlt">X-ray</span> lasing schemes. Specifically, high-resolution <span class="hlt">X-ray</span> spectra were collected under controlled geometric and target conditions using both red and green light laser excitation in the KMS Chroma laser. Three groups of <span class="hlt">X-ray</span> spectra were collected with highly-dispersive <span class="hlt">X-ray</span> crystals at wavelengths centered at 12.543, 13.781 and 14.458 A corresponding to He- and H-like lines from fluorine. Two specially-designed flat crystal spectrographs employing film shutters were used with pairs of beryl and TAP crystals. The spectra from potential lasant and pump candidates could be recorded on the same spectrogram to aid in identifying <span class="hlt">X-ray</span> line coincidences. In cases where wavelengths were measured in both the red and green laser work, agreement within 1-3 mA was obtained for the L-series <span class="hlt">X-ray</span> lines. Within this accuracy range, five L series <span class="hlt">X-ray</span> lines, mostly 2p-3d transitions from the metals Cr, Mn, and Ni, had wavelength values coincident to K-series lines in fluorine.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6288788','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6288788"><span>Human genome sequencing with direct <span class="hlt">x-ray</span> holographic imaging</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Rhodes, C.K.</p> <p>1993-06-08</p> <p>Direct holographic imaging of biological materials is widely applicable to the study of the structure, properties and action of genetic material. This particular application involves the sequencing of the human genome where prospective genomic imaging technology is composed of three subtechnologies, name an <span class="hlt">x-ray</span> holographic camera, suitable chemistry and enzymology for the preparation of tagged DNA samples, and the illuminator in the form of an <span class="hlt">x-ray</span> laser. We report appropriate <span class="hlt">x-ray</span> camera, embodied by the instrument developed by MCR, is available and that suitable chemical and enzymatic procedures exist for the preparation of the necessary tagged DNA strands. Concerning the <span class="hlt">future</span> development of the <span class="hlt">x-ray</span> illuminator. We find that a practical small scale <span class="hlt">x-ray</span> light source is indeed feasible. This outcome requires the use of unconventional physical processes in order to achieve the necessary power-compression in the amplifying medium. The understanding of these new physical mechanisms is developing rapidly. Importantly, although the <span class="hlt">x-ray</span> source does not currently exist, the understanding of these new physical mechanisms is developing rapidly and the research has established the basic scaling laws that will determine the properties of the <span class="hlt">x-ray</span> illuminator. When this <span class="hlt">x-ray</span> source becomes available, an extremely rapid and cost effective instrument for 3-D imaging of biological materials can be applied to a wide range of biological structural assays, including the base-pair sequencing of the human genome and many questions regarding its higher levels of organization.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..DPPUO6002H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..DPPUO6002H"><span>Compact Laser-Compton <span class="hlt">X-ray</span> Source at LLNL</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hwang, Yoonwoo; Marsh, Roark; Gibson, David; Anderson, Gerald; Barty, Christopher; Tajima, Toshiki</p> <p>2016-10-01</p> <p>The scaling of laser-Compton <span class="hlt">X-ray</span> and gamma-ray sources is dependent upon high-current, low-emittance accelerator operation and implementation of efficient laser-electron interaction architectures. Laser-Compton <span class="hlt">X-rays</span> have been produced using the unique compact X-band linear accelerator at LLNL operated in a novel multibunch mode, and results agree extremely well with modeling predictions. An Andor <span class="hlt">X-ray</span> CCD camera and image plates have been calibrated and used to characterize the 30 keV laser-Compton <span class="hlt">X-ray</span> beam. The <span class="hlt">X-ray</span> source size and the effect of scintillator blur have been measured. K-edge absorption measurements using thin metallic foils confirm the production of narrow energy spread <span class="hlt">X-rays</span> and results validate <span class="hlt">X-ray</span> image simulations. <span class="hlt">Future</span> plans for medically relevant imaging will be discussed with facility upgrades to enable 250 keV <span class="hlt">X-ray</span> production. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21187668','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21187668"><span>Size, concentration and incubation time dependence of gold nanoparticle uptake into pancreas cancer cells and its <span class="hlt">future</span> application to <span class="hlt">X-Ray</span> Drug Delivery System.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Trono, Jade Dungao; Mizuno, Kazue; Yusa, Noritaka; Matsukawa, Takehisa; Yokoyama, Kazuhito; Uesaka, Mitsuru</p> <p>2011-01-01</p> <p>One of the restrictions in the potential use of gold markers for medical imaging/tracking of harder tumors is its size. We propose to use gold nanoparticles which, due to its small size, can be administered conveniently via intravenous injection. One of the factors that determine the clinical utility of nanoparticles is the ability to enter cells. In this report, the stability of gold nanoparticles mixed with different media was determined by UV-vis spectroscopy. Gold nanoparticle size was confirmed by TEM. Intracellular uptake using different gold nanoparticle sizes, incubation times and concentrations were analyzed using Atomic Absorption Spectrometry (AAS). Temperature dependence uptake was also measured using AAS. The results showed that pancreas cancer cells uptake 20 nm gold nanoparticles preferentially compared to other gold nanoparticle sizes. Efficient accumulation of gold nanoparticles into pancreas cancer cells can be achieved at longer incubation time and higher concentration. The findings of this study will help in the design and optimization of the gold nanoparticle-based agents for therapeutic and diagnostic applications of <span class="hlt">X-ray</span> Drug Delivery System.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.2427K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.2427K"><span>A new <span class="hlt">planetary</span> mapping for <span class="hlt">future</span> space missions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Karachevtseva, Irina; Kokhanov, Alexander; Rodionova, Janna; Zubarev, Anatoliy; Nadezhdina, Irina; Kreslavsky, Mikhail; Oberst, Jürgen</p> <p>2015-04-01</p> <p>The wide studies of Solar system, including different <span class="hlt">planetary</span> bodies, were announced by new Russian space program. Their geodesy and cartography support provides by MIIGAiK Extraterrestrial Laboratory (http://mexlab.miigaik.ru/eng) in frames of the new project "Studies of Fundamental Geodetic Parameters and Topography of Planets and Satellites". The objects of study are satellites of the outer planets (satellites of Jupiter - Europa, Calisto and Ganymede; Saturnine satellite Enceladus), some planets (Mercury and Mars) and the satellites of the terrestrial planets - Phobos (Mars) and the Moon (Earth). The new research project, which started in 2014, will address the following important scientific and practical tasks: - Creating new three-dimensional geodetic control point networks of satellites of the outer planets using innovative photogrammetry techniques; - Determination of fundamental geodetic parameters and study size, shape, and spin parameters and to create the basic framework for research of their surfaces; - Studies of relief of <span class="hlt">planetary</span> bodies and comparative analysis of general surface characteristics of the Moon, Mars, and Mercury, as well as studies of morphometric parameters of volcanic formations on the Moon and Mars; - Modeling of meteoritic bombardment of celestial bodies and the study of the dynamics of particle emissions caused by a meteorite impacts; - Development of geodatabase for studies of <span class="hlt">planetary</span> bodies, including creation of object catalogues, (craters and volcanic forms, etc.), and thematic mapping using GIS technology. The significance of the project is defined both by necessity of obtaining fundamental characteristics of the Solar System bodies, and practical tasks in preparation for <span class="hlt">future</span> Russian and international space missions to the Jupiter system (Laplace-P and JUICE), the Moon (Luna-Glob and Luna-Resource), Mars (Exo-Mars), Mercury (Bepi-Colombo), and possible mission to Phobos (project Boomerang). For cartographic support of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/982195','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/982195"><span>Ultrafast <span class="hlt">X-ray</span> Sources</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>George Neil</p> <p>2010-04-19</p> <p>Since before the scattering of <span class="hlt">X-rays</span> off of DNA led to the first understanding of the double helix structure, sources of <span class="hlt">X-rays</span> have been an essential tool for scientists examining the structure and interactions of matter. The resolution of a microscope is proportional to the wavelength of light so <span class="hlt">x-rays</span> can see much finer structures than visible light, down to single atoms. In addition, the energy of <span class="hlt">X-rays</span> is resonant with the core atomic levels of atoms so with appropriate wavelengths the placement of specific atoms in a large molecule can be determined. Over 10,000 scientists use synchrotron sources, storage rings of high energy electrons, each year worldwide. As an example of such use, virtually every picture of a protein or drug molecule that one sees in the scientific press is a reconstruction based on <span class="hlt">X-ray</span> scattering of synchrotron light from the crystallized form of that molecule. Unfortunately those pictures are static and proteins work through configuration (shape) changes in response to energy transfer. To understand how biological systems work requires following the energy flow to these molecules and tracking how shape changes drive their interaction with other molecules. We'd like to be able to freeze the action of these molecules at various steps along the way with an <span class="hlt">X-ray</span> strobe light. How fast does it have to be? To actually get a picture of a molecule in a fixed configuration requires <span class="hlt">X-ray</span> pulses as short as 30 femtoseconds (1/30 of a millionth of a millionth of a second). To capture the energy flow through changes in electronic levels requires a faster strobe, less than 1 femtosecond! And to acquire such information in smaller samples with higher accuracy demands brighter and brighter <span class="hlt">X-rays</span>. Unfortunately modern synchrotrons (dubbed 3rd Generation Light Sources) cannot deliver such short bright pulses of <span class="hlt">X-rays</span>. An entirely new approach is required, linear-accelerator (linac-)-based light sources termed 4th or Next Generation Light Sources</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008uvun.conf..218F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008uvun.conf..218F"><span>Ultraluminous <span class="hlt">X-ray</span> Sources.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fabrika, S.; Sholukhova, O.; Abolmasov, P.</p> <p>2008-12-01</p> <p>We discuss a new type of <span class="hlt">X-ray</span> sources discovered in galaxies -- ultraluminous <span class="hlt">X-ray</span> sources (ULXs). They are of two order of magnitude brighter in <span class="hlt">X-rays</span> than the brightest Galactic black holes. Two mod- els of ULXs are discussed: "intermediate mass" black holes, 100 - 10000 solar masses, with standard accretion disks, and "stellar mass" black holes with su- percritical accretion disks like that in the Galactic object SS 433. A study of gas nebulae surrounding these objects gives us a new important information on the central sources. The observed <span class="hlt">X-ray</span> radiation of ULXs is not enough to power their nebulae. To understand both spectra and power of the nebulae one needs a powerful UV source. The ULXs must be such bright in UV range as they are in <span class="hlt">X-rays</span>. Spectroscopy of gas filaments surrounding SS 433 proves that the intrinsic face-on luminosity of the supercritical accretion disk in the far UV region to be "sim; 10^40 erg/s. We expect that observations of ULXs with the WSO-UV Observatory, measurements their UV fluxes and spectral slopes solve the problem of ULXs between the two known models of these sources.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19842886','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19842886"><span><span class="hlt">X-rays</span> surgical revolution.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Toledo-Pereyra, Luis H</p> <p>2009-01-01</p> <p>Wilhelm Roentgen (1845-1923) created a surgical revolution with the discovery of the <span class="hlt">X-rays</span> in late 1895 and the subsequent introduction of this technique for the management of surgical patients. No other physician or scientist had ever imagined such a powerful and worthwhile discovery. Other scientists paved the way for Roentgen to approach the use of these new <span class="hlt">X-rays</span> for medical purposes. In this way, initially, and prior to Roentgen, Thompson, Hertz, and Lenard applied themselves to the early developments of this technology. They made good advances but never reached the clearly defined understanding brought about by Roentgen. The use of a Crookes tube, a barium platinocyanide screen, with fluorescent light and the generation of energy to propagate the cathode rays were the necessary elements for the conception of an <span class="hlt">X-ray</span> picture. On November 8, 1895, Roentgen began his experiments on <span class="hlt">X-ray</span> technology when he found that some kind of rays were being produced by the glass of the tube opposite to the cathode. The development of a photograph successfully completed this early imaging process. After six intense weeks of research, on December 22, he obtained a photograph of the hand of his wife, the first <span class="hlt">X-ray</span> ever made. This would be a major contribution to the world of medicine and surgery.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhRvL.116h0801S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhRvL.116h0801S"><span><span class="hlt">X-ray</span> Echo Spectroscopy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shvyd'ko, Yuri</p> <p>2016-02-01</p> <p><span class="hlt">X-ray</span> echo spectroscopy, a counterpart of neutron spin echo, is being introduced here to overcome limitations in spectral resolution and weak signals of the traditional inelastic <span class="hlt">x-ray</span> scattering (IXS) probes. An image of a pointlike <span class="hlt">x-ray</span> source is defocused by a dispersing system comprised of asymmetrically cut specially arranged Bragg diffracting crystals. The defocused image is refocused into a point (echo) in a time-reversal dispersing system. If the defocused beam is inelastically scattered from a sample, the echo signal acquires a spatial distribution, which is a map of the inelastic scattering spectrum. The spectral resolution of the echo spectroscopy does not rely on the monochromaticity of the <span class="hlt">x</span> <span class="hlt">rays</span>, ensuring strong signals along with a very high spectral resolution. Particular schemes of <span class="hlt">x-ray</span> echo spectrometers for 0.1-0.02 meV ultrahigh-resolution IXS applications (resolving power >108 ) with broadband ≃5 - 13 meV dispersing systems are introduced featuring more than 103 signal enhancement. The technique is general, applicable in different photon frequency domains.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/AD0622328','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/AD0622328"><span>AN <span class="hlt">X-RAY</span> STUDY OF THE ETHYLENE GLYCOLMONTMORILLONITE COMPLEX.</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p></p> <p>SOILS, * MONTMORILLONITE , *GLYCOLS, *<span class="hlt">X</span> <span class="hlt">RAY</span> SPECTROSCOPY, <span class="hlt">X</span> <span class="hlt">RAY</span> SPECTRA, <span class="hlt">X</span> <span class="hlt">RAY</span> SPECTRA, <span class="hlt">X</span> <span class="hlt">RAY</span> SPECTRA, CLAY MINERALS, COMPLEX COMPOUNDS, FOURIER ANALYSIS, CRYSTAL STRUCTURE, THERMAL PROPERTIES, MATHEMATICAL MODELS.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20170007529','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20170007529"><span>Development of Multilayer Coatings for Hard <span class="hlt">X-Ray</span> Optics at NASA Marshall Space Flight Center</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gurgew, Danielle N.; Broadway, David M.; Ramsey, Brian; Gregory, Don</p> <p>2017-01-01</p> <p>Broadband <span class="hlt">X-ray</span> multilayer coatings are under development at NASA MSFC for use on <span class="hlt">future</span> astronomical <span class="hlt">X-ray</span> telescopes. Multilayer coatings deposited onto the reflecting surfaces of <span class="hlt">X-ray</span> optics can provide a large bandpass enabling observations of higher energy astrophysical objects and phenomena.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22318258','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22318258"><span><span class="hlt">X-ray</span> fluorescence holography.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hayashi, Kouichi; Happo, Naohisa; Hosokawa, Shinya; Hu, Wen; Matsushita, Tomohiro</p> <p>2012-03-07</p> <p><span class="hlt">X-ray</span> fluorescence holography (XFH) is a method of atomic resolution holography which utilizes fluorescing atoms as a wave source or a monitor of the interference field within a crystal sample. It provides three-dimensional atomic images around a specified element and has a range of up to a few nm in real space. Because of this feature, XFH is expected to be used for medium-range local structural analysis, which cannot be performed by <span class="hlt">x-ray</span> diffraction or <span class="hlt">x-ray</span> absorption fine structure analysis. In this article, we explain the theory of XFH including solutions to the twin-image problem, an advanced measuring system, and data processing for the reconstruction of atomic images. Then, we briefly introduce our recent applications of this technique to the analysis of local lattice distortions in mixed crystals and nanometer-size clusters appearing in the low-temperature phase of a shape-memory alloy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ARA%26A..55..303K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ARA%26A..55..303K"><span>Ultraluminous <span class="hlt">X-Ray</span> Sources</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kaaret, Philip; Feng, Hua; Roberts, Timothy P.</p> <p>2017-08-01</p> <p>We review observations of ultraluminous <span class="hlt">X-ray</span> sources (ULXs). <span class="hlt">X-ray</span> spectroscopic and timing studies of ULXs suggest a new accretion state distinct from those seen in Galactic stellar-mass black hole binaries. The detection of coherent pulsations indicates the presence of neutron-star accretors in three ULXs and therefore apparently super-Eddington luminosities. Optical and <span class="hlt">X-ray</span> line profiles of ULXs and the properties of associated radio and optical nebulae suggest that ULXs produce powerful outflows, also indicative of super-Eddington accretion. We discuss models of super-Eddington accretion and their relation to the observed behaviors of ULXs. We review the evidence for intermediate mass black holes in ULXs. We consider the implications of ULXs for super-Eddington accretion in active galactic nuclei, heating of the early universe, and the origin of the black hole binary recently detected via gravitational waves.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20080043892&hterms=sulphur&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dsulphur','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20080043892&hterms=sulphur&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dsulphur"><span><span class="hlt">X-ray</span> Timing Measurements</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Strohmayer, T.</p> <p>2008-01-01</p> <p>We present new, extended <span class="hlt">X-ray</span> timing measurements of the ultra-compact binary candidates V407 Vul and RX J0806.3+1527 (J0806), as well as a summary of the first high resolution <span class="hlt">X-ray</span> spectra of 50806 obtained with the Chandra/LETG. The temporal baseline for both objects is approximately 12 years, and our measurements confirm the secular spin-up in their <span class="hlt">X-ray</span> periods. The spin-up rate in 50806 is remarkably uniform at 3.55x10(exp -16)Hz/s, with a measurement precision of 0.2%. We place a limit (90% confidence) on 1 d dot nu < 4x10(exp -26)Hz/sq s. Interestingly, for V407 Vul we find the first evidence that the spin-up rate is slowing, with d dot\</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AAS...22052112M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AAS...22052112M"><span>Solar Hard <span class="hlt">X-ray</span> Observations with NuSTAR</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Marsh, Andrew; Smith, D. M.; Krucker, S.; Hudson, H. S.; Hurford, G. J.; White, S. M.; Mewaldt, R. A.; Harrison, F. A.; Grefenstette, B. W.; Stern, D.</p> <p>2012-05-01</p> <p>High-sensitivity imaging of coronal hard <span class="hlt">X-rays</span> allows detection of freshly accelerated nonthermal electrons at the acceleration site. A few such observations have been made with Yohkoh and RHESSI, but a leap in sensitivity could help pin down the time, place, and manner of reconnection. Around the time of this meeting, the Nuclear Spectroscopic Telescope ARray (NuSTAR), a NASA Small Explorer for high energy astrophysics that uses grazing-incidence optics to focus <span class="hlt">X-rays</span> up to 80 keV, will be launched. Three weeks will be dedicated to solar observing during the baseline two-year mission. NuSTAR will be 200 times more sensitive than RHESSI in the hard <span class="hlt">X-ray</span> band. This will allow the following new observations, among others: 1) Extrapolation of the micro/nanoflare distribution by two orders of magnitude down in flux; 2) Search for hard <span class="hlt">X-rays</span> from network nanoflares (soft <span class="hlt">X-ray</span> bright points) and evaluation of their role in coronal heating; 3) Discovery of hard <span class="hlt">X-ray</span> bremsstrahlung from the electron beams driving type III radio bursts, and measurement of their electron spectrum; 4) Hard <span class="hlt">X-ray</span> studies of polar soft <span class="hlt">X-ray</span> jets and impulsive solar energetic particle events at the edge of coronal holes; 5) Study of coronal bremsstrahlung from particles accelerated by coronal mass ejections as they are first launched; 6) Study of particles at the coronal reconnection site when flare footpoints and loops are occulted; 7) Search for weak high-temperature coronal plasmas in active regions that are not flaring; and 8) Search for hypothetical axion particles created in the solar core via the hard <span class="hlt">X-ray</span> signal from their conversion to <span class="hlt">X-rays</span> in the coronal magnetic field. NuSTAR will also serve as a pathfinder for a <span class="hlt">future</span> dedicated space mission with enhanced capabilities, such as a satellite version of the FOXSI sounding rocket.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011SPD....42.1501S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011SPD....42.1501S"><span>Solar Hard <span class="hlt">X-ray</span> Observations with NuSTAR</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Smith, David M.; Krucker, S.; Hudson, H. S.; Hurford, G. J.; White, S. M.; Mewaldt, R. A.; Stern, D.; Grefenstette, B. W.; Harrison, F. A.</p> <p>2011-05-01</p> <p>High-sensitivity imaging of coronal hard <span class="hlt">X-rays</span> allows detection of freshly accelerated nonthermal electrons at the acceleration site. A few such observations have been made with Yohkoh and RHESSI, but a leap in sensitivity could help pin down the time, place, and manner of reconnection. In 2012, the Nuclear Spectroscopic Telescope Array (NuSTAR), a NASA Small Explorer for high energy astrophysics that uses grazing-incidence optics to focus <span class="hlt">X-rays</span> up to 80 keV, will be launched. NuSTAR is capable of solar pointing, and three weeks will be dedicated to solar observing during the baseline two-year mission. NuSTAR will be 200 times more sensitive than RHESSI in the hard <span class="hlt">X-ray</span> band. This will allow the following new observations, among others: 1) Extrapolation of the micro/nanoflare distribution by two orders of magnitude down in flux 2) Search for hard <span class="hlt">X-rays</span> from network nanoflares (soft <span class="hlt">X-ray</span> bright points) and evaluation of their role in coronal heating 3) Discovery of hard <span class="hlt">X-ray</span> bremsstrahlung from the electron beams driving type III radio bursts, and measurement of their electron spectrum 4) Hard <span class="hlt">X-ray</span> studies of polar soft <span class="hlt">X-ray</span> jets and impulsive solar energetic particle events at the edge of coronal holes, and comparison of these events with observations of 3He and other particles in interplanetary space 5) Study of coronal bremsstrahlung from particles accelerated by coronal mass ejections as they are first launched 6) Study of particles at the coronal reconnection site when flare footpoints are occulted; and 7) Search for hypothetical axion particles created in the solar core via the hard <span class="hlt">X-ray</span> signal from their conversion to <span class="hlt">X-rays</span> in the coronal magnetic field. NuSTAR will also serve as a pathfinder for a <span class="hlt">future</span> dedicated space mission with enhanced capabilities, such as a satellite version of the FOXSI sounding rocket.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6389739','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6389739"><span><span class="hlt">X-ray</span> diffraction measurement of residual stresses in delta plutonium</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Steinmeyer, P.A.</p> <p>1990-09-11</p> <p>Residual stresses in delta plutonium can be measured by the <span class="hlt">x-ray</span> diffractometer method. This was accomplished with the aid of an experimental tantalum <span class="hlt">x-ray</span> target. Preliminary experiments are encouraging and indicate that stresses may be determined precisely and rapidly. <span class="hlt">Future</span> work will involve determination of <span class="hlt">x-ray</span> elastic constants, instrument calibration with stress-free standards, higher <span class="hlt">x-ray</span> power and more sophisticated monochromatization methods. 4 refs., 4 figs., 1 tab.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20030001787','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20030001787"><span>Portable <span class="hlt">X-Ray</span> Device</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1983-01-01</p> <p>Portable <span class="hlt">x-ray</span> instrument developed by NASA now being produced commercially as an industrial tool may soon find further utility as a medical system. The instrument is Lixiscope - Low Intensity <span class="hlt">X-Ray</span> Imaging Scope -- a self-contained, battery-powered fluoroscope that produces an instant image through use of a small amount of radioactive isotope. Originally developed by Goddard Space Flight Center, Lixiscope is now being produced by Lixi, Inc. which has an exclusive NASA license for one version of the device.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000PhDT........87P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000PhDT........87P"><span>Coherent <span class="hlt">x-ray</span> diffraction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pitney, John Allen</p> <p></p> <p>Conventional <span class="hlt">x-ray</span> diffraction has historically been done under conditions such that the measured signal consists of an incoherent addition of scattering which is coherent only on a length scale determined by the properties of the beam. The result of the incoherent summation is a statistical averaging over the whole illuminated volume of the sample, which yields certain kinds of information with a high degree of precision and has been key to the success of <span class="hlt">x-ray</span> diffraction in a variety of applications. Coherent <span class="hlt">x-ray</span> scattering techniques, such as coherent <span class="hlt">x-ray</span> diffraction (CXD) and <span class="hlt">x-ray</span> intensity fluctuation spectroscopy (XIFS), attempt to reduce or eliminate any incoherent averaging so that specific, local structures couple to the measurement without being averaged out. In the case of XIFS, the result is analogous to dynamical light scattering, but with sensitivity to length scales less than 200 nm and time scales from 10-3 s to 103 s. When combined with phase retrieval, CXD represents an imaging technique with the penetration, in situ capabilities, and contrast mechanisms associated with <span class="hlt">x-rays</span> and with a spatial resolution ultimately limited by the <span class="hlt">x-ray</span> wavelength. In practice, however, the spatial resolution of CXD imaging is limited by exposure to about 100 A. This thesis describes CXD measurements of the binary alloy Cu3Au and the adaptation of phase retrieval methods for the reconstruction of real-space images of Cu3Au antiphase domains. The theoretical foundations of CXD are described in Chapter 1 as derived from the kinematical formulation for <span class="hlt">x-ray</span> diffraction and from the temporal and spatial coherence of radiation. The antiphase domain structure of Cu 3Au is described, along with the associated reciprocal-space structure which is measured by CXD. CXD measurements place relatively stringent requirements on the coherence properties of the beam and on the detection mechanism of the experiment; these requirements and the means by which they have been</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19860021152','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19860021152"><span>Cosmic <span class="hlt">X-ray</span> physics</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mccammon, D.; Cox, D. P.; Kraushaar, W. L.; Sanders, W. T.</p> <p>1986-01-01</p> <p>The analysis of the beryllium-filtered data from Flight 17.020 was completed. The data base provided by the Wisconsin diffuse <span class="hlt">X-ray</span> sky survey is being analyzed by correlating the B and C band emission with individual velocity components of neutral hydrogen. Work on a solid state detector to be used in high resolution spectroscopy of diffuse or extend <span class="hlt">X-ray</span> sources is continuing. A series of 21 cm observations was completed. A paper on the effects of process parameter variation on the reflectivity of sputter-deposited tungsten-carvon multilayers was published.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/12804238','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/12804238"><span><span class="hlt">X-rays</span> from stars.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Güdel, Manuel</p> <p>2002-09-15</p> <p>More than two years of observation with Chandra and XMM-Newton has provided a rich harvest of new results on the physics of stellar coronae and winds. High-resolution <span class="hlt">X-ray</span> spectroscopy in particular has opened new windows to the structure, the dynamics and the composition of stellar atmospheres. The present paper presents selected results from the areas of hot and cool stars and star formation, summarizing new views of the thermal structure and energy release in stellar coronae, observations of magnetically active brown dwarfs, the structure of winds in hot stars, the physics in colliding-wind binary systems, and <span class="hlt">X-rays</span> from protostars and stellar jets.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.radiologyinfo.org/en/info.cfm?pg=chestrad','NIH-MEDLINEPLUS'); return false;" href="https://www.radiologyinfo.org/en/info.cfm?pg=chestrad"><span>Chest <span class="hlt">X-Ray</span> (Chest Radiography)</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... News Physician Resources Professions Site Index A-Z <span class="hlt">X-ray</span> (Radiography) - Chest Chest <span class="hlt">x-ray</span> uses a very ... limitations of Chest Radiography? What is a Chest <span class="hlt">X-ray</span> (Chest Radiography)? The chest <span class="hlt">x-ray</span> is the ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA639571','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA639571"><span>Compact Flash <span class="hlt">X-Ray</span> Units</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1995-07-01</p> <p>Flash <span class="hlt">x-ray</span> units are used to diagnose pulsed power driven experiments on the Pegasus machine at Los Alamos. Several unique designs of Marx powered...employing an <span class="hlt">x-ray</span> tube configuration which allows closely spaced <span class="hlt">x-ray</span> emitting anodes. These units all emit a 10 ns FWHM <span class="hlt">x-ray</span> pulse. Their Marx banks</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20020076041','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20020076041"><span>Micro-System Technology for <span class="hlt">X-ray</span> Astronomy</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Schattenburg, Mark L.</p> <p>2002-01-01</p> <p>This research investigation was devoted to developing micro-system and nanotechnology for <span class="hlt">x-ray</span> astronomy optics. The goal was to develop and demonstrate new types of lightweight, high accuracy <span class="hlt">x-ray</span> optics for <span class="hlt">future</span> high throughput, high resolution <span class="hlt">x-ray</span> telescopes such as Constellation X (Con-X) and MAXIM. A number of significant accomplishments were reported under this program, which are summarized below. Most of this work has been reported in journal and conference proceedings and in presentations to NASA and at international meeting (see Bibliography).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110015220','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110015220"><span>Next-Generation <span class="hlt">X-Ray</span> Astronomy</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>White, Nicholas E.</p> <p>2011-01-01</p> <p>The <span class="hlt">future</span> timing capabilities in <span class="hlt">X-ray</span> astronomy will be reviewed. This will include reviewing the missions in implementation: Astro-H, GEMS, SRG, and ASTROSAT; those under study: currently ATHENA and LOFT; and new technologies that may enable <span class="hlt">future</span> missions e.g. Lobster eye optics. These missions and technologies will bring exciting new capabilities across the entire time spectrum from micro-seconds to years that e.g. will allow us to probe close to the event horizon of black holes and constrain the equation of state of neutron stars.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1030619','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1030619"><span>The Race To <span class="hlt">X-ray</span> Microbeam and Nanobeam Science</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ice, Gene E; Budai, John D; Pang, Judy</p> <p>2011-01-01</p> <p><span class="hlt">X-ray</span> microbeams are an emerging characterization tool with transformational implications for broad areas of science ranging from materials structure and dynamics, geophysics and environmental science to biophysics and protein crystallography. In this review, we discuss the race toward sub-10 nm- <span class="hlt">x-ray</span> beams with the ability to penetrate tens to hundreds of microns into most materials and with the ability to determine local (crystal) structure. Examples of science enabled by current micro/nanobeam technologies are presented and we provide a perspective on <span class="hlt">future</span> directions. Applications highlighted are chosen to illustrate the important features of various submicron beam strategies and to highlight the directions of current and <span class="hlt">future</span> research. While it is clear that <span class="hlt">x-ray</span> microprobes will impact science broadly, the practical limit for hard <span class="hlt">x-ray</span> beam size, the limit to trace element sensitivity, and the ultimate limitations associated with near-atomic structure determinations are the subject of ongoing research.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014SPIE.9144E..1HR','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014SPIE.9144E..1HR"><span>Development of light weight replicated <span class="hlt">x-ray</span> optics, II</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Romaine, S.; Bruni, R.; Choi, B.; Jensen, C.; Kilaru, K.; Ramsey, B.; Sampath, S.</p> <p>2014-07-01</p> <p>NASA'S <span class="hlt">future</span> <span class="hlt">X-ray</span> astronomy missions will require <span class="hlt">X-ray</span> optics that have large effective area while remaining lightweight, and cost effective. Some <span class="hlt">X-ray</span> missions, such as XMM-Newton[1] , and the upcoming Spectrum-Röntgen- Gamma[2] mission use an electroformed nickel replication (ENR) process[3] to fabricate the nested grazing incidence <span class="hlt">X-ray</span> telescope mirror shells for an array of moderate resolution, moderate effective area telescopes. We are developing a process to fabricate metal-ceramic replicated optics which will be lighter weight than current nickel replicated technology. Our technology development takes full advantage of the replication technique by fabricating large diameter mirrors with thin cross sections allowing maximum nesting and increase in collecting area. This will lead to <span class="hlt">future</span> cost effective missions with large effective area and lightweight optics with good angular resolution. Recent results on fabrication and testing of these optics is presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20080012231','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20080012231"><span><span class="hlt">X-ray</span> exposure sensor and controller</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Berdahl, C. Martin (Inventor)</p> <p>1977-01-01</p> <p>An exposure controller for <span class="hlt">x-ray</span> equipment is provided, which comprises a portable and accurate sensor which can be placed adjacent to and directly beneath the area of interest of an <span class="hlt">x-ray</span> plate, and which measures the amount of exposure received by that area, and turns off the <span class="hlt">x-ray</span> equipment when the exposure for the particular area of interest on the <span class="hlt">x-ray</span> plate reaches the value which provides an optimal <span class="hlt">x-ray</span> plate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008HEAD...10.3707N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008HEAD...10.3707N"><span>Wide Field <span class="hlt">X-ray</span> Telescope</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Norman, Colin Arthur; WFXT Team</p> <p>2008-03-01</p> <p>The Wide Field <span class="hlt">X-Ray</span> Telescope (WFXT) that will carry out an unprecedented <span class="hlt">X-ray</span> survey of galaxy clusters and groups, AGNs and QSOs, and galaxies. WFXT is a medium-class strategic mission that will address key questions in both Cosmic Origins and Physics of the Cosmos. WFXT will be orders of magnitude more effective than previous and planned <span class="hlt">X-ray</span> missions in performing surveys to a given limiting flux. The angular resolution of 5” will be finer than that provided by any currently planned large-area <span class="hlt">X-ray</span> survey and highly efficient at discriminating AGNs and QSOs from extended emission from sources such as galaxies and clusters. The Burrows-Burg-Giacconi optical solution gives an approximately constant angular resolution of 3-5 arc seconds across a field of 1-1.5 degrees diameter. A preliminary telescope design provides a resulting light grasp that is an order of magnitude larger than current or <span class="hlt">future</span> missions. We plan a combination of three surveys and, at each flux limit, WFXT will cover three orders of magnitude more area than all previous and planned missions, with the deep 100 deg2 survey reaching the same flux limit as the deepest Chandra surveys to date. The WFXT mission addresses key cosmological and astrophysical science objectives including: the formation and evolution of clusters of galaxies with the associated cosmological and astrophysical implications; black hole formation and evolution; the interaction of black-hole driven AGNs with cluster and galaxy properties; and the high-energy stellar component and the hot- ISM phase of galaxies WFXT is a mission for the entire astronomical community. The data from these surveys will be made readily available to the community in timely data releases to be used in a multitude of multi-waveband studies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008SPIE.7011E..1JM','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008SPIE.7011E..1JM"><span>Wide field <span class="hlt">x-ray</span> telescope mission</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Murray, Stephen S.; Norman, Colin; Ptak, Andrew; Giacconi, Riccardo; Weisskopf, Martin; Ramsey, Brian; Bautz, Mark; Vikhliniin, Alexey; Brandt, Niel; Rosati, Piero; Weaver, Harold; Allen, Steve; Flanagan, Kathryn</p> <p>2008-07-01</p> <p>The Wide Field <span class="hlt">X-Ray</span> Telescope (WFXT) will carry out an unprecedented <span class="hlt">X-ray</span> survey of galaxy clusters and groups, AGNs and QSOs, and galaxies. WFXT is a medium-class strategic mission that will address key questions in both Cosmic Origins and Physics of the Cosmos. WFXT will be orders of magnitude more effective than previous <span class="hlt">X-ray</span> missions in performing surveys to a given limiting flux. The angular resolution of ~5" will be finer than provided by any currently planned large-area <span class="hlt">X-ray</span> survey and highly efficient at discriminating AGNs and QSOs from extended emission from sources such as galaxies and clusters. The Burrows, Burg and Giacconi ideal optical solution gives an approximately constant angular resolution of 3-5 arc seconds across a field of 1-1.5 degrees diameter. A preliminary telescope design provides a resulting grasp an order of magnitude larger than current or <span class="hlt">future</span> missions. We plan a combination of three surveys and, at each flux limit, WFXT will cover orders of magnitude more area than all previous and planned missions, with the deep 100 deg2 survey reaching the same flux limit as the deepest Chandra surveys to date. The WFXT mission addresses key cosmological and astrophysical science objectives including: the formation and evolution of clusters of galaxies with the associated cosmological and astrophysical implications; black hole formation and evolution; the interaction of black-hole driven AGNs with cluster and galaxy properties; and the high-energy stellar component and the hot ISM phase of galaxies WFXT is a mission for the entire astronomical community. The data from these surveys will be made readily available to the community in timely data releases to be used in a multitude of multi-waveband studies that will revolutionize astronomy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22570018','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22570018"><span>TU-G-207-00: Emerging Applications of <span class="hlt">X-Ray</span> Imaging</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p></p> <p>2015-06-15</p> <p>Last few years has witnessed the development of novel of <span class="hlt">X-ray</span> imaging modalities, such as spectral CT, phase contrast CT, and <span class="hlt">X-ray</span> acoustic/fluorescence/luminescence imaging. This symposium will present the recent advances of these emerging <span class="hlt">X-ray</span> imaging modalities and update the attendees with knowledge in various related topics, including <span class="hlt">X-ray</span> photon-counting detectors, <span class="hlt">X-ray</span> physics underlying the emerging applications beyond the traditional <span class="hlt">X-ray</span> imaging, image reconstruction for the novel modalities, characterization and evaluation of the systems, and their practical implications. In addition, the concept and practical aspects of <span class="hlt">X-ray</span> activatable targeted nanoparticles for molecular <span class="hlt">X-ray</span> imaging will be discussed in the context of <span class="hlt">X-ray</span> fluorescence and luminescence CT. Learning Objectives: Present background knowledge of various emerging <span class="hlt">X-ray</span> imaging techniques, such as spectral CT, phase contrast CT and <span class="hlt">X-ray</span> fluorescence/luminescence CT. Discuss the practical need, technical aspects and current status of the emerging <span class="hlt">X-ray</span> imaging modalities. Describe utility and <span class="hlt">future</span> impact of the new generation of <span class="hlt">X-ray</span> imaging applications.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008SPIE.6945E..16D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008SPIE.6945E..16D"><span><span class="hlt">X-ray</span> backscatter imaging</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dinca, Dan-Cristian; Schubert, Jeffrey R.; Callerame, J.</p> <p>2008-04-01</p> <p>In contrast to transmission <span class="hlt">X-ray</span> imaging systems where inspected objects must pass between source and detector, Compton backscatter imaging allows both the illuminating source as well as the <span class="hlt">X-ray</span> detector to be on the same side of the target object, enabling the inspection to occur rapidly and in a wide variety of space-constrained situations. A Compton backscatter image is similar to a photograph of the contents of a closed container, taken through the container walls, and highlights low atomic number materials such as explosives, drugs, and alcohol, which appear as especially bright objects by virtue of their scattering characteristics. Techniques for producing <span class="hlt">X-ray</span> images based on Compton scattering will be discussed, along with examples of how these systems are used for both novel security applications and for the detection of contraband materials at ports and borders. Differences between transmission and backscatter images will also be highlighted. In addition, tradeoffs between Compton backscatter image quality and scan speed, effective penetration, and <span class="hlt">X-ray</span> source specifications will be discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/EJ118198.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/EJ118198.pdf"><span>Rontgen's Discovery of <span class="hlt">X</span> <span class="hlt">Rays</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Thumm, Walter</p> <p>1975-01-01</p> <p>Relates the story of Wilhelm Conrad Rontgen and presents one view of the extent to which the discovery of the <span class="hlt">x-ray</span> was an accident. Reconstructs the sequence of events that led to the discovery and includes photographs of the lab where he worked and replicas of apparatus used. (GS)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/7270509','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/biblio/7270509"><span>Focused <span class="hlt">X-ray</span> source</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Piestrup, M.A.; Boyers, D.G.; Pincus, C.I.; Maccagno, P.</p> <p>1990-08-21</p> <p>Disclosed is an intense, relatively inexpensive <span class="hlt">X-ray</span> source (as compared to a synchrotron emitter) for technological, scientific, and spectroscopic purposes. A conical radiation pattern produced by a single foil or stack of foils is focused by optics to increase the intensity of the radiation at a distance from the conical radiator. 8 figs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110012841','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110012841"><span>Stellar <span class="hlt">X-Ray</span> Polarimetry</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Swank, J.</p> <p>2011-01-01</p> <p>Most of the stellar end-state black holes, pulsars, and white dwarfs that are <span class="hlt">X-ray</span> sources should have polarized <span class="hlt">X-ray</span> fluxes. The degree will depend on the relative contributions of the unresolved structures. Fluxes from accretion disks and accretion disk corona may be polarized by scattering. Beams and jets may have contributions of polarized emission in strong magnetic fields. The Gravity and Extreme Magnetism Small Explorer (GEMS) will study the effects on polarization of strong gravity of black holes and strong magnetism of neutron stars. Some part of the flux from compact stars accreting from companion stars has been reflected from the companion, its wind, or accretion streams. Polarization of this component is a potential tool for studying the structure of the gas in these binary systems. Polarization due to scattering can also be present in <span class="hlt">X-ray</span> emission from white dwarf binaries and binary normal stars such as RS CVn stars and colliding wind sources like Eta Car. Normal late type stars may have polarized flux from coronal flares. But <span class="hlt">X-ray</span> polarization sensitivity is not at the level needed for single early type stars.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19950009786','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19950009786"><span>Alpha proton <span class="hlt">x</span> <span class="hlt">ray</span> spectrometer</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rieder, Rudi; Waeke, H.; Economou, T.</p> <p>1994-01-01</p> <p>Mars Pathfinder will carry an alpha-proton <span class="hlt">x</span> <span class="hlt">ray</span> spectrometer (APX) for the determination of the elemental chemical composition of Martian rocks and soils. The instrument will measure the concentration of all major and some minor elements, including C, N, and O at levels above typically 1 percent.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1995lock.reptR....H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1995lock.reptR....H"><span>Stellar <span class="hlt">x-ray</span> flares</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Haisch, B.; Uchida, Y.; Kosugi, T.; Hudson, H. S.</p> <p>1995-01-01</p> <p>What is the importance of stellar <span class="hlt">X-ray</span> flares to astrophysics, or even more, to the world at large? In the case of the Sun, changes in solar activity at the two temporal extremes can have quite significant consequences. Longterm changes in solar activity, such as the Maunder Minimum, can apparently lead to non-negligible alterations of the earth's climate. The extreme short term changes are solar flares, the most energetic of which can cause communications disruptions, power outages and ionizing radiation levels amounting to medical <span class="hlt">X-ray</span> dosages on long commercial flights and even potentially lethal exposures for unshielded astronauts. Why does the Sun exhibit such behaviour? Even if we had a detailed knowledge of the relevant physical processes on the Sun - which we may be on the way to having in hand as evidenced by these Proceedings- our understanding would remain incomplete in regard to fundamental causation so long as we could not say whether the Sun is, in this respect, unique among the stars. This current paper discusses the stellar <span class="hlt">x-ray</span> flare detections and astronomical models (quasi-static cooling model and two-ribbon model) that are used to observe the <span class="hlt">x-ray</span> emission.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/867505','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/867505"><span>Focused <span class="hlt">X-ray</span> source</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Piestrup, Melvin A.; Boyers, David G.; Pincus, Cary I.; Maccagno, Pierre</p> <p>1990-01-01</p> <p>An intense, relatively inexpensive <span class="hlt">X-ray</span> source (as compared to a synchrotron emitter) for technological, scientific, and spectroscopic purposes. A conical radiation pattern produced by a single foil or stack of foils is focused by optics to increase the intensity of the radiation at a distance from the conical radiator.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20130014127','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20130014127"><span><span class="hlt">X-Ray</span> Diffractive Optics</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Dennis, Brian; Li, Mary; Skinner, Gerald</p> <p>2013-01-01</p> <p><span class="hlt">X-ray</span> optics were fabricated with the capability of imaging solar <span class="hlt">x-ray</span> sources with better than 0.1 arcsecond angular resolution, over an order of magnitude finer than is currently possible. Such images would provide a new window into the little-understood energy release and particle acceleration regions in solar flares. They constitute one of the most promising ways to probe these regions in the solar atmosphere with the sensitivity and angular resolution needed to better understand the physical processes involved. A circular slit structure with widths as fine as 0.85 micron etched in a silicon wafer 8 microns thick forms a phase zone plate version of a Fresnel lens capable of focusing approx. =.6 keV <span class="hlt">x-rays</span>. The focal length of the 3-cm diameter lenses is 100 microns, and the angular resolution capability is better than 0.1 arcsecond. Such phase zone plates were fabricated in Goddard fs Detector Development Lab. (DDL) and tested at the Goddard 600-microns <span class="hlt">x-ray</span> test facility. The test data verified that the desired angular resolution and throughput efficiency were achieved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/936110','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/936110"><span>Compact <span class="hlt">x-ray</span> source and panel</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sampayon, Stephen E.</p> <p>2008-02-12</p> <p>A compact, self-contained <span class="hlt">x-ray</span> source, and a compact <span class="hlt">x-ray</span> source panel having a plurality of such <span class="hlt">x-ray</span> sources arranged in a preferably broad-area pixelized array. Each <span class="hlt">x-ray</span> source includes an electron source for producing an electron beam, an <span class="hlt">x-ray</span> conversion target, and a multilayer insulator separating the electron source and the <span class="hlt">x-ray</span> conversion target from each other. The multi-layer insulator preferably has a cylindrical configuration with a plurality of alternating insulator and conductor layers surrounding an acceleration channel leading from the electron source to the <span class="hlt">x-ray</span> conversion target. A power source is connected to each <span class="hlt">x-ray</span> source of the array to produce an accelerating gradient between the electron source and <span class="hlt">x-ray</span> conversion target in any one or more of the <span class="hlt">x-ray</span> sources independent of other <span class="hlt">x-ray</span> sources in the array, so as to accelerate an electron beam towards the <span class="hlt">x-ray</span> conversion target. The multilayer insulator enables relatively short separation distances between the electron source and the <span class="hlt">x-ray</span> conversion target so that a thin panel is possible for compactness. This is due to the ability of the plurality of alternating insulator and conductor layers of the multilayer insulators to resist surface flashover when sufficiently high acceleration energies necessary for <span class="hlt">x-ray</span> generation are supplied by the power source to the <span class="hlt">x-ray</span> sources.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004NIMPA.520..354P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004NIMPA.520..354P"><span>Low-temperature detectors in <span class="hlt">X-ray</span> astronomy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Porter, F. Scott</p> <p>2004-03-01</p> <p>The most compelling nature of <span class="hlt">X-ray</span> astronomy is its richness and scale. Almost every observable object in the sky either naturally emits <span class="hlt">X-ray</span> radiation or can be observed through <span class="hlt">X-ray</span> absorption. Current <span class="hlt">X-ray</span> observatories such as Chandra and XMM-Newton have considerably advanced our understanding of many of these systems by using imaging <span class="hlt">X-ray</span> cameras and dispersed <span class="hlt">X-ray</span> spectrometers. However, it is the combination of these two techniques to provide a true broadband, high spectral-resolution, imaging spectrometer that will drive the next revolution in <span class="hlt">X-ray</span> astronomy. This is where Low-temperature detectors (LTDs) can play a key role but also where the science will continuously challenge the technology. In this brief overview we will explore the constraints that both the science goals and the space environment place on the implementation of LTDs, how current missions such as XQC and Astro-E2 have met these challenges, and where <span class="hlt">future</span> missions such as Constellation-X, XEUS, and NeXT will drive LTD instruments to a much larger scale. Finally, we will address scaling issues in current LTD detectors and where the LTD community needs to proceed to address both the science goals and expectations of the astrophysics community.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19950005891','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19950005891"><span><span class="hlt">X-ray</span> and gamma ray astronomy detectors</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Decher, Rudolf; Ramsey, Brian D.; Austin, Robert</p> <p>1994-01-01</p> <p><span class="hlt">X-ray</span> and gamma ray astronomy was made possible by the advent of space flight. Discovery and early observations of celestial <span class="hlt">x-rays</span> and gamma rays, dating back almost 40 years, were first done with high altitude rockets, followed by Earth-orbiting satellites> once it became possible to carry detectors above the Earth's atmosphere, a new view of the universe in the high-energy part of the electromagnetic spectrum evolved. Many of the detector concepts used for <span class="hlt">x-ray</span> and gamma ray astronomy were derived from radiation measuring instruments used in atomic physics, nuclear physics, and other fields. However, these instruments, when used in <span class="hlt">x-ray</span> and gamma ray astronomy, have to meet unique and demanding requirements related to their operation in space and the need to detect and measure extremely weak radiation fluxes from celestial <span class="hlt">x-ray</span> and gamma ray sources. Their design for <span class="hlt">x-ray</span> and gamma ray astronomy has, therefore, become a rather specialized and rapidly advancing field in which improved sensitivity, higher energy and spatial resolution, wider spectral coverage, and enhanced imaging capabilities are all sought. This text is intended as an introduction to <span class="hlt">x-ray</span> and gamma ray astronomy instruments. It provides an overview of detector design and technology and is aimed at scientists, engineers, and technical personnel and managers associated with this field. The discussion is limited to basic principles and design concepts and provides examples of applications in past, present, and <span class="hlt">future</span> space flight missions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PASP..129f2001M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PASP..129f2001M"><span><span class="hlt">X-Ray</span> Emissions from Accreting White Dwarfs: A Review</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mukai, K.</p> <p>2017-06-01</p> <p>Interacting binaries in which a white dwarf accretes material from a companion—cataclysmic variables (CVs) in which the mass donor is a Roche-lobe filling star on or near the main sequence, and symbiotic stars in which the mass donor is a late type giant—are relatively commonplace. They display a wide range of behaviors in the optical, <span class="hlt">X-rays</span>, and other wavelengths, which still often baffle observers and theorists alike. Here I review the existing body of research on <span class="hlt">X-ray</span> emissions from these objects for the benefits of both experts and newcomers to the field. I provide introductions to the past and current <span class="hlt">X-ray</span> observatories, the types of known <span class="hlt">X-ray</span> emissions from these objects, and the data analysis techniques relevant to this field. I then summarize of our knowledge regarding the <span class="hlt">X-ray</span> emissions from magnetic CVs, non-magnetic CVs and symbiotic stars, and novae in eruption. I also discuss space density and the <span class="hlt">X-ray</span> luminosity functions of these binaries and their contribution to the integrated <span class="hlt">X-ray</span> emission from the Galaxy. I then discuss open questions and <span class="hlt">future</span> prospects.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20170005826&hterms=reviews&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dreviews','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20170005826&hterms=reviews&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dreviews"><span><span class="hlt">X-Ray</span> Emissions from Accreting White Dwarfs: A Review</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mukai, K.</p> <p>2017-01-01</p> <p>Interacting binaries in which a white dwarf accretes material from a companion-cataclysmic variables (CVs) in which the mass donor is a Roche-lobe filling star on or near the main sequence, and symbiotic stars in which the mass donor is a late type giant-are relatively commonplace. They display a wide range of behaviors in the optical, <span class="hlt">X-rays</span>, and other wavelengths, which still often baffle observers and theorists alike. Here I review the existing body of research on <span class="hlt">X-ray</span> emissions from these objects for the benefits of both experts and newcomers to the field. I provide introductions to the past and current <span class="hlt">X-ray</span> observatories, the types of known <span class="hlt">X-ray</span> emissions from these objects, and the data analysis techniques relevant to this field. I then summarize of our knowledge regarding the <span class="hlt">X-ray</span> emissions from magnetic CVs, non-magnetic CVs and symbiotic stars, and novae in eruption. I also discuss space density and the <span class="hlt">X-ray</span> luminosity functions of these binaries and their contribution to the integrated <span class="hlt">X-ray</span> emission from the Galaxy. I then discuss open questions and <span class="hlt">future</span> prospects.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1991SPIE.1496..247S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1991SPIE.1496..247S"><span>Issues in the repair of <span class="hlt">x-ray</span> masks</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Stewart, Diane K.; Doherty, John A.</p> <p>1991-03-01</p> <p>Although full implementation of <span class="hlt">x-ray</span> lithography as a production technology remains a few years in the <span class="hlt">future</span>, there are now many world wide efforts to accelerate this introduction. Unlike other more common lithographic techniques, such as image projection, x-rya lithography requires the fabrication of a mask with a thick absorber to efficiently block the <span class="hlt">X-rays</span>. This important distinction from the reticles used in wafer steppers requires a completely new approach to many of the techniques of mask making, including inspection and repairs. Focused ion beam systems have been suggested as a possible repair strategy, and a number of groups have utilized the inherent advantages of FIB methods to repair <span class="hlt">X-ray</span> masks in the laboratory. Although FIB systems have achieve substantial acceptance in the photomask making community for repair of chrome masks and reticles, a simple reapplication of these systems to repair of <span class="hlt">X-ray</span> masks will not produce the quality levels required in <span class="hlt">X</span>- <span class="hlt">ray</span> lithography. The purpose of this paper will be to review the primary technical problems in the repair of <span class="hlt">X-ray</span> masks and to discuss the implications of these requirements on the design of an FIB system. The current state-of-the-art in <span class="hlt">X-ray</span> mask repair will be reviewed and some unique results will be presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21049262','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21049262"><span>Hard <span class="hlt">X-Ray</span> Nanoprobe based on Refractive <span class="hlt">X-Ray</span> Lenses</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Schroer, C. G.; Patommel, J.; Boye, P.; Feldkamp, J.; Kurapova, O.; Lengeler, B.; Burghammer, M.; Riekel, C.; Vincze, L.; Hart, A. van der; Kuechler, M.</p> <p>2007-01-19</p> <p>At synchrotron radiation sources, parabolic refractive <span class="hlt">x-ray</span> lenses allow one to built both full field and scanning microscopes in the hard <span class="hlt">x-ray</span> range. The latter microscope can be operated in transmission, fluorescence, and diffraction mode, giving chemical, elemental, and structural contrast. For scanning microscopy, a small and intensive microbeam is required. Parabolic refractive <span class="hlt">x-ray</span> lenses with a focal distance in the centimeter range, so-called nanofocusing lenses (NFLs), can generate hard <span class="hlt">x-ray</span> nanobeams in the range of 100 nm and below, even at short distances, i. e., 40 to 70 m from the source. Recently, a 47 x 55 nm2 beam with 1.7 {center_dot} 108 ph/s at 21 keV (monochromatic, Si 111) was generated using silicon NFLs in crossed geometry at a distance of 47m from the undulator source at beamline ID13 of ESRF. This beam is not diffraction limited, and smaller beams may become available in the <span class="hlt">future</span>. Lenses made of more transparent materials, such as boron or diamond, could yield an increase in flux of one order of magnitude and have a larger numerical aperture. For these NFLs, diffraction limits below 20 nm are conceivable. Using adiabatically focusing lenses, the diffraction limit can in principle be pushed below 5 nm.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014A%26A...567A..89T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014A%26A...567A..89T"><span>The Swift <span class="hlt">X-ray</span> Telescope Cluster Survey. II. <span class="hlt">X-ray</span> spectral analysis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tozzi, P.; Moretti, A.; Tundo, E.; Liu, T.; Rosati, P.; Borgani, S.; Tagliaferri, G.; Campana, S.; Fugazza, D.; D'Avanzo, P.</p> <p>2014-07-01</p> <p> < 0.4. We derive the luminosity-temperature relation for these 46 sources, finding good agreement with previous studies. Conclusions: Thanks to the good <span class="hlt">X-ray</span> spectral quality and the low background of Swift/XRT, we are able to measure ICM temperatures and <span class="hlt">X-ray</span> luminosities for the 46 sources with redshifts. Once redshifts are available for the remaining 26 sources, this sample will constitute a well-characterized, flux-limited catalog of clusters distributed over a broad redshift range (0.1 ≤ z ≤ 1.0) providing a statistically complete view of the cluster population with a selection function that allows a proper treatment of any measurement bias. The quality of the SWXCS sample is comparable to other samples available in the literature and obtained with much larger <span class="hlt">X-ray</span> telescopes. Our results have interesting implications for the design of <span class="hlt">future</span> <span class="hlt">X-ray</span> survey telescopes, characterized by good-quality PSF over the entire field of view and low background. Tables 1 and 2 and Appendix A are available in electronic form at http://www.aanda.orgCatalog and data products of SWXCS, constantly updated, are made available to the public through the websites http://www.arcetri.astro.it/SWXCS/ and http://swxcs.ustc.edu.cn/</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20060026347&hterms=importance+survey&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dimportance%2Bsurvey','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20060026347&hterms=importance+survey&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dimportance%2Bsurvey"><span>Normal and Starburst Galaxies in Deep <span class="hlt">X-ray</span> Surveys</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hornschemeier, Ann</p> <p>2006-01-01</p> <p>This talk will cover progress of the last several years in unraveling the nature of normal and starburst galaxies in deep <span class="hlt">X-ray</span> surveys. This includes discussion of the normal galaxy <span class="hlt">X-ray</span> Luminosity Function in deep field and cluster surveys and what it tells us about the binary populations in galaxies. The utility of broad band <span class="hlt">X-ray</span> emission, especially as compared to other multiwavelength measurements of current/recent star formation, will be reviewed. These broad band <span class="hlt">X-ray</span> measurements of star formation are based upon <span class="hlt">X-ray</span>/Star Formation Rate correlations that span the currently available redshift range (0 < z < 1). I will also discuss new efforts underway to systematically characterize the <span class="hlt">X-ray</span> emission from galaxies in group and cluster environments, including a new effort underway in the Coma cluster of galaxies. I will finish with discussion of the redshift frontier for studies of <span class="hlt">X-ray</span> star formation, currently 2 approx.4, where the UV-selected Lyman Break galaxies are the best glimpse we have into <span class="hlt">X-ray</span> emission from star formation in the early Universe. Lyman Break galaxies are of particular interest due to the overlap in basic properties with starburst galaxies in the more local Universe. Understanding the outflows in such starburst galaxies is of critical importance to constraining the "stellar" portion of cosmic feedback. The talk will close with a brief discussion of distant normal galaxy science with <span class="hlt">future</span> <span class="hlt">X-ray</span> observatories such as the upcoming Con-X/XEUS mission(s).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015APS..SHK.H1001M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015APS..SHK.H1001M"><span>Coherent <span class="hlt">X-ray</span> Imaging Techniques for Shock Physics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Montgomery, David</p> <p>2015-06-01</p> <p><span class="hlt">X-ray</span> radiography has been used for several decades in dynamic experiments to measure material flow in extreme conditions via absorption of <span class="hlt">x-rays</span> propagating through the materials. Image contrast in traditional radiography is determined by the absorption coefficients and areal densities of the materials at a given <span class="hlt">x-ray</span> wavelength, and often limits these measurements to materials with sufficiently high atomic numbers and areal density, while low-Z materials and small areal density variations are completely transparent and not visible in the image. Coherent <span class="hlt">x-ray</span> sources, such as those found at synchrotrons and <span class="hlt">x-ray</span> free-electron lasers, provide new opportunities for imaging dynamic experiments due to their high spatial and spectral coherence, high brightness and short temporal duration (<100 ps). Phase-sensitive techniques, such as phase contrast imaging (PCI), rely on the overlap and interference of the <span class="hlt">x-rays</span> due to spatial variations in their transmitted phase, and are enabled primarily by high spatial coherence of the <span class="hlt">x-ray</span> source. Objects that are otherwise transparent to <span class="hlt">x-rays</span> can be imaged with PCI, and small variations in areal density become visible that would be not observable with traditional radiography. In this talk an overview of PCI will be given, and current applications of this technique in high-energy density physics, shock physics and material dynamics will be presented. Other <span class="hlt">future</span> uses of imaging using coherent <span class="hlt">x-ray</span> sources in dynamic high-pressure experiments will be discussed. Work performed under the auspices of DOE by LANL under Contract DE-AC52-06NA25396.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1981PhDT........41J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1981PhDT........41J"><span><span class="hlt">X-Ray</span> Streak Camera.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jaanimagi, Paul Ants</p> <p></p> <p>Streak cameras are acknowledged as the only instruments capable of unambiguously diagnosing optical phenomena with a time resolution of the order of a picosecond on a single shot basis. As streak cameras become more extensively used for diagnostics in such fields as picosecond laser pulse generation, photo-chemistry, laser produced plasma studies, the instrument's capabilities are also being examined and limitations are becoming noticeable. One of the aims of this dissertation is to investigate the question of streak camera fidelity, especially with regard to linearity and dynamic range as a function of the time resolution. It is shown that the dynamic range is proportional to the product of the instrumental time resolution and the pulse width. The implications for femtosecond diagnostic capability are self-evident but a study of the sources of the limitations suggest distinct avenues for improving the systems. Since a streak camera employs an electron analog of the optical signal, clearly space charge will cause significant distortion at large current densities and consequently limit the dynamic range. Problems also result from nonlinear photocathode response, electron lens distortions, time of flight dispersion, phosphor reciprocity failure and nonlinear intensifier gain. The solution for some of these problems requires modifications to the basic tube designs. The National Research Council of Canada <span class="hlt">x-ray</span> streak camera (based on a RCA C73435 image tube) was used as the starting point for testing electron optic designs and implementing the desired modifications. The objective of this work was to improve our <span class="hlt">x-ray</span> diagnostic in sensitivity and in time resolution capability to < 10 ps. Ultimately this streak camera was to be used to time resolve the <span class="hlt">x</span> -<span class="hlt">ray</span> emission from plasmas produced by the COCO II and high pressure CO(,2) laser facilities at NRC. Features of the redesigned <span class="hlt">x-ray</span> streak camera include: a large photocathode area (1.3 x 25 mm), a photoelectron</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016cosp...41E1534P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016cosp...41E1534P"><span><span class="hlt">X-ray</span> reprocessing in binaries</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Paul, Biswajit</p> <p>2016-07-01</p> <p>We will discuss several aspects of <span class="hlt">X-ray</span> reprocessing into <span class="hlt">X-rays</span> or longer wavelength radiation in different kinds of binary systems. In high mass <span class="hlt">X-ray</span> binaries, reprocessing of hard <span class="hlt">X-rays</span> into emission lines or lower temperature black body emission is a useful tool to investigate the reprocessing media like the stellar wind, clumpy structures in the wind, accretion disk or accretion stream. In low mass <span class="hlt">X-ray</span> binaries, reprocessing from the surface of the companion star, the accretion disk, warps and other structures in the accretion disk produce signatures in longer wavelength radiation. <span class="hlt">X-ray</span> sources with temporal structures like the <span class="hlt">X-ray</span> pulsars and thermonuclear burst sources are key in such studies. We will discuss results from several new investigations of <span class="hlt">X-ray</span> reprocessing phenomena in <span class="hlt">X-ray</span> binaries.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.P21D1878W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.P21D1878W"><span>NASA's <span class="hlt">Planetary</span> Aeolian Laboratory: Facilities and Plans for <span class="hlt">Future</span> Availability</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Williams, D. A.</p> <p>2012-12-01</p> <p>The <span class="hlt">Planetary</span> Aeolian Laboratory (PAL), supported by NASA's <span class="hlt">Planetary</span> Geology and Geophysics (PG&G) program, is a unique facility used for conducting experiments and simulations of aeolian processes (windblown particles) under different <span class="hlt">planetary</span> atmospheric environments, including Earth, Mars, and Saturn's moon Titan. With the death of PAL founder Ronald Greeley in 2011, there is concern in the <span class="hlt">planetary</span> aeolian community whether the PAL will be maintained for continued use by <span class="hlt">planetary</span> scientists. This presentation will review the PAL facilities, what are their current capabilities, how can interested scientists propose to NASA to use them, and what are the long-term plans for their continued use. The PAL includes one of the nation's largest pressure chambers for conducting low-pressure research. The primary purpose of the PAL is to enable scientific research into aeolian processes under controlled laboratory conditions, and enable testing and calibration of spacecraft instruments and components for NASA's solar system missions, including those requiring a large volume simulated Martian atmosphere. The PAL consists of: 1) the Mars Wind Tunnel (MARSWIT) and 2) Titan Wind Tunnel (TWT) located in the Structural Dynamics Building (N-242) at the NASA Ames Research Center (ARC) in Mountain View, California and administered by Arizona State University. Also available (although not officially part of the PAL facilities) is: 3) an ambient pressure/temperature wind tunnel (ASUWIT) and 4) a vortex (dust devil) generator (ASUVG) on the Tempe campus of Arizona State University (ASU), which is part of the ASU School of Earth and Space Exploration (SESE) and the Ronald Greeley Center for <span class="hlt">Planetary</span> Studies. The TWT just came online in June 2012, and upgrades are underway to both the hardware and software of the MARSWIT and ASUWIT. Long-term plans are for ASU to continue to manage these facilities, to make them as capable as possible, so that they may be useful resources to NASA</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19850052266&hterms=space+probe&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dspace%2Bprobe','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19850052266&hterms=space+probe&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dspace%2Bprobe"><span><span class="hlt">Future</span> studies of <span class="hlt">planetary</span> rings by space probes</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stone, E. C.</p> <p>1984-01-01</p> <p>Recent space probe observations of the rings of Jupiter and Saturn have furnished a substantial enhancement of the current understanding of the outer planets' rings. Voyager 2 offers further opportunities for the study of the Neptune and Uranus ring systems. The Galileo mission to Jupiter furnishes the first opportunity for long term space probe studies of a <span class="hlt">planetary</span> ring system. It is suggested that an appropriately instrumented Saturn orbiter would not only provide a similar opportunity for the study of the Saturn rings, but may also be the only means by which to adequately address the nature of the diverse phenomena displayed by this prototypical <span class="hlt">planetary</span> ring system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1995AAS...187.7203G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1995AAS...187.7203G"><span>The Hard <span class="hlt">X-Ray</span> Telescope Mission</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gorenstein, P.; Joensen, K.; Romaine, S.; Worrall, D.; Cameron, R.; Weisskopf, M.; Ramsey, B.; Bilbro, J.; Kroeger, R.; Gehrels, N.; Parsons, A.; Smither, R.; Christensen, F.; Citterio, O.; von Ballmoos, P.</p> <p>1995-12-01</p> <p>The Hard <span class="hlt">X-Ray</span> Telescope (HXT) mission concept contains focusing telescopes that collectively, observe simultaneously from the ultraviolet to 100 keV and in several narrow bands extending to 1 MeV. In pointed observations HXT is expected to have an order of magnitude more sensitivity and much finer angular resolution in the 10 to 100 keV band than all current and currently planned <span class="hlt">future</span> missions, and considerably more sensitivity for detecting narrow lines in the 100 keV to 1 MeV regime. The detectors are small, cooled arrays of relatively low mass with very good energy resolution and some polarization sensitivity. HXT contains two types of hard <span class="hlt">X-ray</span> telescopes. One type, called the modular modular telescope (MMT) utilizes a novel type of multilayer coating and small graze angles to extend the regime of focusing to 100keV. There is a two stage imaging detector at each focus, a CCD for <span class="hlt">X-rays</span> < 10 keV followed down stream by either a germanium strip array or cadmium zinc telluride array for 10-100 keV <span class="hlt">X-rays</span>. The other type of telescope, called the Laue Crystal Telescope (LCT) is a single adjustable array of several hundred Ge crystals that focus by Laue scattering. Individual picomotors adjust the angle of each crystal to diffract photons of a fixed energy to the same point along the optic axis where they converge upon a movable array of cooled germanium detectors. The LCT will have high sensitivity for detecting narrow <span class="hlt">X-ray</span> lines of known energy such as those expected from Type 1 supernova. The UV monitor is a three telescope system that provides coverage in the ultraviolet band for study of time correlated changes across the broad electromagnetic spectrum of an AGN such as are expected in ``reverberation'' models. A WWW page will be created as a public bulletin board. This work is supported by NASA grant NAG8-1194</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016SPIE.9847E..02H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016SPIE.9847E..02H"><span>Aviation security <span class="hlt">x-ray</span> detection challenges</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Harvey, T.</p> <p>2016-05-01</p> <p>In this paper, a review of the background and some drivers are provided for <span class="hlt">X-ray</span> screening for aviation security. Some of the key considerations are highlighted along with impacts of the image-based approaches and signature approaches. The role of information theory is discussed along with some recent work that may influence the technical direction by posing the question: "what measurements, parameters and metrics should be considered in <span class="hlt">future</span> system design?" A path forward should be based on information theory, however electronic machines will likely interface with humans and be dollar-cost driven, so ultimately solutions must consider additional parameters other than only technical performance factors.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016HEAD...1512005B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016HEAD...1512005B"><span>Enhanced <span class="hlt">X-ray</span> Emission from Early Universe Analog Galaxies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brorby, Matthew; Kaaret, Philip; Prestwich, Andrea H.; Mirabel, I. Felix; Feng, Hua</p> <p>2016-04-01</p> <p><span class="hlt">X-rays</span> from binaries containing compact objects may have played an important role in heating the early Universe. Here we discuss our findings from <span class="hlt">X-ray</span> studies of blue compact dwarf galaxies (BCDs), Lyman break analogs (LBAs), and Green Pea galaxies (GP), all of which are considered local analogs to high redshift galaxies. We find enhanced <span class="hlt">X-ray</span> emission per unit star-formation rate which strongly correlates with decreasing metallicity. We find evidence for the existence of a L_X-SFR-Metallicity plane for star-forming galaxies. The exact properties of <span class="hlt">X-ray</span> emission in the early Universe affects the timing and morphology of reionization, both being observable properties of current and <span class="hlt">future</span> radio observations of the redshifted 21cm signal from neutral hydrogen.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4420547','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4420547"><span><span class="hlt">X-ray</span> imaging detectors for synchrotron and XFEL sources</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Hatsui, Takaki; Graafsma, Heinz</p> <p>2015-01-01</p> <p>Current trends for <span class="hlt">X-ray</span> imaging detectors based on hybrid and monolithic detector technologies are reviewed. Hybrid detectors with photon-counting pixels have proven to be very powerful tools at synchrotrons. Recent developments continue to improve their performance, especially for higher spatial resolution at higher count rates with higher frame rates. Recent developments for <span class="hlt">X-ray</span> free-electron laser (XFEL) experiments provide high-frame-rate integrating detectors with both high sensitivity and high peak signal. Similar performance improvements are sought in monolithic detectors. The monolithic approach also offers a lower noise floor, which is required for the detection of soft <span class="hlt">X-ray</span> photons. The link between technology development and detector performance is described briefly in the context of potential <span class="hlt">future</span> capabilities for <span class="hlt">X-ray</span> imaging detectors. PMID:25995846</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_22 --> <div id="page_23" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="441"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25995846','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25995846"><span><span class="hlt">X-ray</span> imaging detectors for synchrotron and XFEL sources.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hatsui, Takaki; Graafsma, Heinz</p> <p>2015-05-01</p> <p>Current trends for <span class="hlt">X-ray</span> imaging detectors based on hybrid and monolithic detector technologies are reviewed. Hybrid detectors with photon-counting pixels have proven to be very powerful tools at synchrotrons. Recent developments continue to improve their performance, especially for higher spatial resolution at higher count rates with higher frame rates. Recent developments for <span class="hlt">X-ray</span> free-electron laser (XFEL) experiments provide high-frame-rate integrating detectors with both high sensitivity and high peak signal. Similar performance improvements are sought in monolithic detectors. The monolithic approach also offers a lower noise floor, which is required for the detection of soft <span class="hlt">X-ray</span> photons. The link between technology development and detector performance is described briefly in the context of potential <span class="hlt">future</span> capabilities for <span class="hlt">X-ray</span> imaging detectors.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6059034','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6059034"><span>Center for <span class="hlt">X-Ray</span> Optics, 1986</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Not Available</p> <p>1987-07-01</p> <p>The Center for <span class="hlt">X-Ray</span> Optics has made substantial progress during the past year on the development of very high resolution <span class="hlt">x-ray</span> technologies, the generation of coherent radiation at <span class="hlt">x-ray</span> wavelengths, and, based on these new developments, had embarked on several scientific investigations that would not otherwise have been possible. The investigations covered in this report are topics on <span class="hlt">x-ray</span> sources, <span class="hlt">x-ray</span> imaging and applications, soft <span class="hlt">x-ray</span> spectroscopy, synchrotron radiation, advanced light source and magnet structures for undulators and wigglers. (LSP)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017NIMPB.395....5G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017NIMPB.395....5G"><span>Effective <span class="hlt">X-ray</span> beam size measurements of an <span class="hlt">X-ray</span> tube and polycapillary <span class="hlt">X-ray</span> lens system using a scanning <span class="hlt">X-ray</span> fluorescence method</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gherase, Mihai R.; Vargas, Andres Felipe</p> <p>2017-03-01</p> <p>Size measurements of an <span class="hlt">X-ray</span> beam produced by an integrated polycapillary <span class="hlt">X-ray</span> lens (PXL) and <span class="hlt">X-ray</span> tube system were performed by means of a scanning <span class="hlt">X-ray</span> fluorescence (SXRF) method using three different metallic wires. The beam size was obtained by fitting the SXRF data with the analytical convolution between a Gaussian and a constant functions. For each chemical element in the wire an effective energy was calculated based on the incident <span class="hlt">X-ray</span> spectrum and its photoelectric cross section. The proposed method can be used to measure the effective <span class="hlt">X-ray</span> beam size in XRF microscopy studies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ASPC..510..395F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ASPC..510..395F"><span>Ultraluminous <span class="hlt">X-ray</span> Sources</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fabrika, S.</p> <p>2017-06-01</p> <p>The origin of Ultraluminous <span class="hlt">X-ray</span> sources (ULXs) in external galaxies whose <span class="hlt">X-ray</span> luminosities exceed those of the brightest black holes in our Galaxy by hundreds and thousands of times is mysterious. Here we report that all nearby persistent ULXs ever spectroscopically observed have the same optical spectra similar to that of SS 433, the only known supercritical accretor in our Galaxy. The spectra are apparently of WNL type (late nitrogen Wolf-Rayet stars) or LBV (luminous blue variables) in their hot state, which are very scarce stellar objects. We find that the spectra do not originate from WNL/LBV type donors and not in heated accretion disks, but from very hot winds from the accretion disks, which have similar physical conditions as the stellar winds from these stars. Our results suggest that bona-fide ULXs must constitute a homogeneous class of objects, which most likely have supercritical accretion disks.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/869279','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/869279"><span>Microgap <span class="hlt">x-ray</span> detector</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Wuest, Craig R.; Bionta, Richard M.; Ables, Elden</p> <p>1994-01-01</p> <p>An <span class="hlt">x-ray</span> detector which provides for the conversion of <span class="hlt">x-ray</span> photons into photoelectrons and subsequent amplification of these photoelectrons through the generation of electron avalanches in a thin gas-filled region subject to a high electric potential. The detector comprises a cathode (photocathode) and an anode separated by the thin, gas-filled region. The cathode may comprise a substrate, such a beryllium, coated with a layer of high atomic number material, such as gold, while the anode can be a single conducting plane of material, such as gold, or a plane of resistive material, such as chromium/silicon monoxide, or multiple areas of conductive or resistive material, mounted on a substrate composed of glass, plastic or ceramic. The charge collected from each electron avalanche by the anode is passed through processing electronics to a point of use, such as an oscilloscope.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/7184218','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/biblio/7184218"><span>Microgap <span class="hlt">x-ray</span> detector</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Wuest, C.R.; Bionta, R.M.; Ables, E.</p> <p>1994-05-03</p> <p>An <span class="hlt">x-ray</span> detector is disclosed which provides for the conversion of <span class="hlt">x-ray</span> photons into photoelectrons and subsequent amplification of these photoelectrons through the generation of electron avalanches in a thin gas-filled region subject to a high electric potential. The detector comprises a cathode (photocathode) and an anode separated by the thin, gas-filled region. The cathode may comprise a substrate, such a beryllium, coated with a layer of high atomic number material, such as gold, while the anode can be a single conducting plane of material, such as gold, or a plane of resistive material, such as chromium/silicon monoxide, or multiple areas of conductive or resistive material, mounted on a substrate composed of glass, plastic or ceramic. The charge collected from each electron avalanche by the anode is passed through processing electronics to a point of use, such as an oscilloscope. 3 figures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17799101','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17799101"><span>Tunable Coherent <span class="hlt">X-rays</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Attwood, D; Halbach, K; Kim, K J</p> <p>1985-06-14</p> <p>A modern 1- to 2-billion-electron-volt synchrotron radiation facility (based on high-brightness electron beams and magnetic undulators) would generate coherent (laser-like) soft <span class="hlt">x-rays</span> of wavelengths as short as 10 angstroms. The radiation would also be broadly tunable and subject to full polarization control. Radiation with these properties could be used for phase- and element-sensitive microprobing of biological assemblies and material interfaces as well as reserch on the production of electronic microstructures with features smaller than 1000 angstroms. These short wavelength capabilities, which extend to the K-absorption edges of carbon, nitrogen, and oxygen, are neither available nor projected for laboratory XUV lasers. Higher energy storage rings (5 to 6 billion electron volts) would generate significantly less coherent radiation and would be further compromised by additional <span class="hlt">x-ray</span> thermal loading of optical components.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22482694','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22482694"><span>New developments in high pressure <span class="hlt">x-ray</span> spectroscopy beamline at High Pressure Collaborative Access Team</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Xiao, Y. M. Chow, P.; Boman, G.; Bai, L. G.; Rod, E.; Bommannavar, A.; Kenney-Benson, C.; Sinogeikin, S.; Shen, G. Y.</p> <p>2015-07-15</p> <p>The 16 ID-D (Insertion Device - D station) beamline of the High Pressure Collaborative Access Team at the Advanced Photon Source is dedicated to high pressure research using <span class="hlt">X-ray</span> spectroscopy techniques typically integrated with diamond anvil cells. The beamline provides <span class="hlt">X-rays</span> of 4.5-37 keV, and current available techniques include <span class="hlt">X-ray</span> emission spectroscopy, inelastic <span class="hlt">X-ray</span> scattering, and nuclear resonant scattering. The recent developments include a canted undulator upgrade, 17-element analyzer array for inelastic <span class="hlt">X-ray</span> scattering, and an emission spectrometer using a polycapillary half-lens. Recent development projects and <span class="hlt">future</span> prospects are also discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20040000691&hterms=REAGENTS&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DREAGENTS','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20040000691&hterms=REAGENTS&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DREAGENTS"><span><span class="hlt">X-Ray</span> Crystallography Reagent</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Morrison, Dennis R. (Inventor); Mosier, Benjamin (Inventor)</p> <p>2003-01-01</p> <p>Microcapsules prepared by encapsulating an aqueous solution of a protein, drug or other bioactive substance inside a semi-permeable membrane by are disclosed. The microcapsules are formed by interfacial coacervation under conditions where the shear forces are limited to 0-100 dynes per square centimeter at the interface. By placing the microcapsules in a high osmotic dewatering solution. the protein solution is gradually made saturated and then supersaturated. and the controlled nucleation and crystallization of the protein is achieved. The crystal-filled microcapsules prepared by this method can be conveniently harvested and stored while keeping the encapsulated crystals in essentially pristine condition due to the rugged. protective membrane. Because the membrane components themselves are <span class="hlt">x-ray</span> transparent, large crystal-containing microcapsules can be individually selected, mounted in <span class="hlt">x-ray</span> capillary tubes and subjected to high energy <span class="hlt">x-ray</span> diffraction studies to determine the 3-D smucture of the protein molecules. Certain embodiments of the microcapsules of the invention have composite polymeric outer membranes which are somewhat elastic, water insoluble, permeable only to water, salts, and low molecular weight molecules and are structurally stable in fluid shear forces typically encountered in the human vascular system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApJ...818..104K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApJ...818..104K"><span><span class="hlt">X-Ray</span>-powered Macronovae</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kisaka, Shota; Ioka, Kunihito; Nakar, Ehud</p> <p>2016-02-01</p> <p>A macronova (or kilonova) was observed as an infrared excess several days after the short gamma-ray burst GRB 130603B. Although the r-process radioactivity is widely discussed as an energy source, it requires a huge mass of ejecta from a neutron star (NS) binary merger. We propose a new model in which the <span class="hlt">X-ray</span> excess gives rise to the simultaneously observed infrared excess via thermal re-emission, and explore what constraints this would place on the mass and velocity of the ejecta. This <span class="hlt">X-ray</span>-powered model explains both the <span class="hlt">X-ray</span> and infrared excesses with a single energy source such as the central engine like a black hole, and allows for a broader parameter region than the previous models, in particular a smaller ejecta mass ˜ {10}-3{--}{10}-2{M}⊙ and higher iron abundance mixed as suggested by general relativistic simulations for typical NS-NS mergers. We also discuss the other macronova candidates in GRB 060614 and GRB 080503, and the implications for the search of electromagnetic counterparts to gravitational waves.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009MNRAS.397L..69E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009MNRAS.397L..69E"><span>Can <span class="hlt">X-rays</span> provide a solution to the abundance discrepancy problem in photoionized nebulae?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ercolano, B.</p> <p>2009-07-01</p> <p>We re-examine the well-known discrepancy between ionic abundances determined via the analysis of recombination lines (RLs) and collisionally excited lines (CELs). We show that abundance variations can be mimicked in a chemically homogeneous medium by the presence of dense (nH > rsim 104 cm-3) <span class="hlt">X-ray</span> irradiated regions which present different ionization and temperature structures from those of the more diffuse medium they are embedded in, which is predominantly ionized by extreme-ultraviolet radiation. The presence of <span class="hlt">X-ray</span> ionized dense clumps or filaments also naturally explains the lower temperatures often measured from OII RLs and from the Balmer jump when compared to temperatures determined by CELs. We discuss the implications for abundances determined via the analysis of CELs and RLs and provide a simple analytical procedure to obtain upward corrections for CEL-determined abundance. While we show that the abundance discrepancy factor and the Balmer Jump temperature determined from observations of the Orion Nebula can simultaneously be reproduced by this model (implying upward corrections for CELs by a factor of 1.15), we find that the required <span class="hlt">X-ray</span> fluxes exceed the known Orion's stellar and diffuse <span class="hlt">X-ray</span> budget, if we assume that the clumps are located at the edge of the blister. We propose, however, that spatially resolved observations may be used to empirically test the model, and outline how the framework developed in this Letter may be applied in the <span class="hlt">future</span> to objects with better constrained geometries (e.g. <span class="hlt">planetary</span> nebulae).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/10127862','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/10127862"><span><span class="hlt">X-ray</span> imaging and <span class="hlt">x-ray</span> source development at Lawrence Livermore National Laboratory</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Trebes, J.; Balhorn, R.; Anderson, E.</p> <p>1993-12-01</p> <p>The Laser Program at Lawrence Livermore National Laboratory has a continuing effort to develop both <span class="hlt">x-ray</span> sources and <span class="hlt">x-ray</span> sources and <span class="hlt">x-ray</span> microscopy. This effort includes the ongoing development of: (1) a wide range of <span class="hlt">x-ray</span> lasers at the Nova Laser Facility, (2) a zone plate lens--multilayer mirror based <span class="hlt">x-ray</span> microscope (3) three dimensional, high resolution <span class="hlt">x-ray</span> microscopy (4) short wavelength, normal incidence multilayer <span class="hlt">x-ray</span> mirrors, (5) compact, high average power lasers for producing <span class="hlt">x-ray</span> lasers and laser plasma <span class="hlt">x-ray</span> sources. We have constructed and operated an <span class="hlt">x-ray</span> laser based transmission <span class="hlt">x-ray</span> microscope. The advantage offered by the <span class="hlt">x-ray</span> laser source is the extreme high brightness allows high resolution images to be made on a timescale faster than that for <span class="hlt">x-ray</span> damage effects to appear. The microscope, consists of: the <span class="hlt">x-ray</span> laser, a multilayer coated, near normal incidence spherical mirror used as a condenser, a silicon nitride specimen holder, an <span class="hlt">x-ray</span> zone plate used as an objective lens, and a microchannel plate <span class="hlt">x-ray</span> detector. The <span class="hlt">x-ray</span> laser used is the Ni-like Ta <span class="hlt">x-ray</span> laser operating with a wavelength of 4.48 nm, a pulselength of 200 spec, a divergence of 10 mrad, and an output energy of 10 microjoules.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014apra.prop...77H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014apra.prop...77H"><span>Next Generation <span class="hlt">X-ray</span> Polarimeter</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hill-Kittle, Joe</p> <p></p> <p> sources that were previously unobtainable within realistic observation times e.g. Active Galactic Nuclei (AGN). Standard photoelectric <span class="hlt">X-ray</span> polarimeter designs are both quantum efficiency (QE) limited and challenging to calibrate due to diffusion of electron signal as it drifts through the gas. Drifting negative ions decreases diffusion to the thermal limit thereby decoupling sensitivity from drift distance and enabling larger detector areas that can be at the focus of larger diameter mirrors and single reflection concentrator optics. NITPCs also allow the selection of constituent gasses and pressures to be based on the optimization of modulation and QE rather than diffusion properties. This versatility enables a large improvement in sensitivity without driving cost and with only moderate increase to mass and power of the detector and/or instrument. Furthermore, the energy band of NGXP will be tunable to maximize the science return. Following the efforts of this proposal NGXP will be proposed as sounding rocket experiment and as a candidate instrument for <span class="hlt">future</span> opportunities. The GSFC polarimeter group has demonstrated NITPCs for several detector concepts. This proposal leverages the previous effort and team expertise with goals to establish the NITPC as the baseline for narrow field observations of faint persistent sources and to improve the technology readiness of associated technologies such as stainless steel gas electron multipliers and finer readout pitch.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/969243','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/969243"><span>Near Edge <span class="hlt">X-Ray</span> Absorption Fine Structure Spectroscopy with <span class="hlt">X-Ray</span> Free-Electron Lasers</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Bernstein, D.P.; Acremann, Y.; Scherz, A.; Burkhardt, M.; Stohr, J.; Beye, M.; Schlotter, W.F.; Beeck, T.; Sorgenfrei, F.; Pietzsch, A.; Wurth, W.; Fohlisch, A.; /Hamburg U.</p> <p>2009-12-11</p> <p>We demonstrate the feasibility of Near Edge <span class="hlt">X-ray</span> Absorption Fine Structure (NEXAFS) spectroscopy on solids by means of femtosecond soft <span class="hlt">x-ray</span> pulses from a free-electron laser (FEL). Our experiments, carried out at the Free-Electron Laser at Hamburg (FLASH), used a special sample geometry, spectrographic energy dispersion, single shot position-sensitive detection and a data normalization procedure that eliminates the severe fluctuations of the incident intensity in space and photon energy. As an example we recorded the {sup 3}D{sub 1} N{sub 4,5}-edge absorption resonance of La{sup 3+}-ions in LaMnO{sub 3}. Our study opens the door for <span class="hlt">x-ray</span> absorption measurements on <span class="hlt">future</span> <span class="hlt">x-ray</span> FEL facilities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/877530','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/877530"><span>Recent and <span class="hlt">Future</span> Observations in the <span class="hlt">X-ray</span> and Gamma-ray Bands: Chandra, Suzaku, GLAST, and NuSTAR</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Madejski, Greg; /SLAC /KIPAC, Menlo Park</p> <p>2005-12-02</p> <p>This paper presents a brief overview of the accomplishments of the Chandra satellite that are shedding light on the origin of high energy particles in astrophysical sources, with the emphasis on clusters of galaxies. It also discusses the prospects for the new data to be collected with instruments recently launched--such as Suzaku--or those to be deployed in the near <span class="hlt">future</span>, and this includes GLAST and NuSTAR.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/sciencecinema/biblio/1045473','SCIGOVIMAGE-SCICINEMA'); return false;" href="http://www.osti.gov/sciencecinema/biblio/1045473"><span>Producing <span class="hlt">X-rays</span> at the APS</span></a></p> <p><a target="_blank" href="http://www.osti.gov/sciencecinema/">ScienceCinema</a></p> <p>None</p> <p>2016-07-12</p> <p>An introduction and overview of the Advanced Photon Source at Argonne National Laboratory, the technology that produces the brightest <span class="hlt">X-ray</span> beams in the Western Hemisphere, and the research carried out by scientists using those <span class="hlt">X-rays</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://medlineplus.gov/ency/imagepages/1607.htm','NIH-MEDLINEPLUS'); return false;" href="https://medlineplus.gov/ency/imagepages/1607.htm"><span>Tuberculosis, advanced - chest <span class="hlt">x-rays</span> (image)</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... tissue, and can cause tissue death. These chest <span class="hlt">x-rays</span> show advanced pulmonary tuberculosis. There are multiple light ... location of cavities within these light areas. The <span class="hlt">x-ray</span> on the left clearly shows that the opacities ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://medlineplus.gov/ency/imagepages/2330.htm','NIH-MEDLINEPLUS'); return false;" href="https://medlineplus.gov/ency/imagepages/2330.htm"><span>Aspergillosis - chest <span class="hlt">x-ray</span> (image)</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... usually occurs in immunocompromised individuals. Here, a chest <span class="hlt">x-ray</span> shows that the fungus has invaded the lung ... are usually seen as black areas on an <span class="hlt">x-ray</span>. The cloudiness on the left side of this ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/5324563','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/5324563"><span>Advances in transmission <span class="hlt">x-ray</span> optics</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ceglio, N.M.</p> <p>1983-01-01</p> <p>Recent developments in <span class="hlt">x-ray</span> optics are reviewed. Specific advances in coded aperture imaging, zone plate lens fabrication, time and space resolved spectroscopy, and CCD <span class="hlt">x-ray</span> detection are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22256796','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22256796"><span>Plate tectonics and <span class="hlt">planetary</span> habitability: current status and <span class="hlt">future</span> challenges.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Korenaga, Jun</p> <p>2012-07-01</p> <p>Plate tectonics is one of the major factors affecting the potential habitability of a terrestrial planet. The physics of plate tectonics is, however, still far from being complete, leading to considerable uncertainty when discussing <span class="hlt">planetary</span> habitability. Here, I summarize recent developments on the evolution of plate tectonics on Earth, which suggest a radically new view on Earth dynamics: convection in the mantle has been speeding up despite its secular cooling, and the operation of plate tectonics has been facilitated throughout Earth's history by the gradual subduction of water into an initially dry mantle. The role of plate tectonics in <span class="hlt">planetary</span> habitability through its influence on atmospheric evolution is still difficult to quantify, and, to this end, it will be vital to better understand a coupled core-mantle-atmosphere system in the context of solar system evolution. © 2012 New York Academy of Sciences.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_23 --> <div id="page_24" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="461"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120008542','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120008542"><span>Traverse Planning Experiments for <span class="hlt">Future</span> <span class="hlt">Planetary</span> Surface Exploration</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hoffman, Stephen J.; Voels, Stephen A.; Mueller, Robert P.; Lee, Pascal C.</p> <p>2012-01-01</p> <p>The purpose of the investigation is to evaluate methodology and data requirements for remotely-assisted robotic traverse of extraterrestrial <span class="hlt">planetary</span> surface to support human exploration program, assess opportunities for in-transit science operations, and validate landing site survey and selection techniques during <span class="hlt">planetary</span> surface exploration mission analog demonstration at Haughton Crater on Devon Island, Nunavut, Canada. Additionally, 1) identify quality of remote observation data sets (i.e., surface imagery from orbit) required for effective pre-traverse route planning and determine if surface level data (i.e., onboard robotic imagery or other sensor data) is required for a successful traverse, and if additional surface level data can improve traverse efficiency or probability of success (TRPF Experiment). 2) Evaluate feasibility and techniques for conducting opportunistic science investigations during this type of traverse. (OSP Experiment). 3) Assess utility of remotely-assisted robotic vehicle for landing site validation survey. (LSV Experiment).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010adap.prop...84G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010adap.prop...84G"><span>Stellar <span class="hlt">X-ray</span> Emission From Magnetically Funneled Shocks</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Guenther, Hans</p> <p></p> <p>Stars and planets form in giant molecular clouds, so they are deeply embedded in their early stages. When they become optically visible, the young stars are still surrounded by a proto-<span class="hlt">planetary</span> disk, where planets evolve. These stars are called classical T Tauri stars (CTTS). A key, yet poorly constrained, parameter for the disk evolution is the stellar high-energy emission. It can ionize the outer layers of the disk, change its chemistry and even drive photoevaporation of the disk. Thus the spectral shape and the temporal variability of the stellar <span class="hlt">X-ray</span> and UV emission shapes the gas and dust properties in some regions of the disk. It sets the photoevaporation timescale which provides an upper limit for planet formation. CTTS still actively accrete mass from their disk. The infalling matter is funneled by the stellar magnetic field and impacts on the star close to free fall velocity. A hot accretion shock develops, which emits <span class="hlt">X-rays</span> which are distinct from any coronal <span class="hlt">X-rays</span>. Eventually the disk disperses and bulk planet formation comes to an end. <span class="hlt">X-ray</span> emitting shocks can still occur at a later stage in stellar evolution, if e.g. the magnetic field is strong enough to funnel the stellar wind to collide in the disk midplane. This so-called magnetically confined wind shock model was originally developed for the A0p star IQ Aur. The magnetically funneled accretion model has been successfully tested for CTTS in a small mass range only; the magnetically confined wind shock model lacks a comparison for high-resolution <span class="hlt">X-ray</span> grating spectra for all but the most massive stars. In this proposal we request funding to analyze three XMM-Newton observations, which will probe <span class="hlt">X-ray</span> emitting shocks in stars with magnetic fields: DN Tau (observed as category C target in cycle 8), a CTTS with much lower mass than previous CTTS with <span class="hlt">X</span>- <span class="hlt">ray</span> grating spectroscopy; MN Lup (to be observed in cycle 9), a prime candidate for simultaneous <span class="hlt">X-ray</span>/Doppler-imaging studies; and IQ Aur (to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1082878','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1082878"><span>Phase-sensitive <span class="hlt">X-ray</span> imager</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Baker, Kevin Louis</p> <p>2013-01-08</p> <p><span class="hlt">X-ray</span> phase sensitive wave-front sensor techniques are detailed that are capable of measuring the entire two-dimensional <span class="hlt">x-ray</span> electric field, both the amplitude and phase, with a single measurement. These Hartmann sensing and 2-D Shear interferometry wave-front sensors do not require a temporally coherent source and are therefore compatible with <span class="hlt">x-ray</span> tubes and also with laser-produced or x-pinch <span class="hlt">x-ray</span> sources.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20080004582','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20080004582"><span>Advanced <span class="hlt">x-ray</span> imaging spectrometer</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Callas, John L. (Inventor); Soli, George A. (Inventor)</p> <p>1998-01-01</p> <p>An <span class="hlt">x-ray</span> spectrometer that also provides images of an <span class="hlt">x-ray</span> source. Coded aperture imaging techniques are used to provide high resolution images. Imaging position-sensitive <span class="hlt">x-ray</span> sensors with good energy resolution are utilized to provide excellent spectroscopic performance. The system produces high resolution spectral images of the <span class="hlt">x-ray</span> source which can be viewed in any one of a number of specific energy bands.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JPhCS.808a1001P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JPhCS.808a1001P"><span>3rd International Conference on <span class="hlt">X-ray</span> Technique</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Potrakhov, N. N.; Gryaznov, A. Yu; Lisenkov, A. A.; Kostrin, D. K.</p> <p>2017-02-01</p> <p>In this preface a brief history, modern aspects and <span class="hlt">future</span> tendencies in development of the <span class="hlt">X-ray</span> technique as seen from the 3rd International Conference on <span class="hlt">X-ray</span> Technique that was held on 24-25 November 2016 in Saint Petersburg, Russia are described On 24-25 November 2016 in Saint Petersburg on the basis of Saint Petersburg State Electrotechnical University “LETI” n. a. V. I. Ulyanov (Lenin) was held the 3rd International Conference on <span class="hlt">X-ray</span> Technique. The tradition to hold a similar conference in our country was laid in Soviet times. The last of them, the All-Union Conference on the Prospects of <span class="hlt">X-ray</span> Tubes and Equipment was organized and held more than a quarter century ago - on 21-23 November 1999, at the initiative and under the leadership of the chief engineer of the Leningrad association of electronic industry “Svetlana” Borovsky Alexander Ivanovich and the chief of special design bureau of <span class="hlt">X-ray</span> devices of “Svetlana” Shchukin Gennady Anatolievich. The most active part in the organization and work of the conference played members of the department of <span class="hlt">X-ray</span> and electron beam instruments of Leningrad Electrotechnical Institute “LETI” (the former name of Saint Petersburg State Electrotechnical University “LETI”), represented by head of the department professor Ivanov Stanislav Alekseevich.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70032790','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70032790"><span>A short working distance multiple crystal <span class="hlt">x-ray</span> spectrometer</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Dickinson, B.; Seidler, G.T.; Webb, Z.W.; Bradley, J.A.; Nagle, K.P.; Heald, S.M.; Gordon, R.A.; Chou, I.-Ming</p> <p>2008-01-01</p> <p>For <span class="hlt">x-ray</span> spot sizes of a few tens of microns or smaller, a millimeter-sized flat analyzer crystal placed ???1 cm from the sample will exhibit high energy resolution while subtending a collection solid angle comparable to that of a typical spherically bent crystal analyzer (SBCA) at much larger working distances. Based on this observation and a nonfocusing geometry for the analyzer optic, we have constructed and tested a short working distance (SWD) multicrystal <span class="hlt">x-ray</span> spectrometer. This prototype instrument has a maximum effective collection solid angle of 0.14 sr, comparable to that of 17 SBCA at 1 m working distance. We find good agreement with prior work for measurements of the Mn K?? <span class="hlt">x-ray</span> emission and resonant inelastic <span class="hlt">x-ray</span> scattering for MnO, and also for measurements of the <span class="hlt">x-ray</span> absorption near-edge structure for Dy metal using L??2 partial-fluorescence yield detection. We discuss <span class="hlt">future</span> applications at third- and fourth-generation light sources. For concentrated samples, the extremely large collection angle of SWD spectrometers will permit collection of high-resolution <span class="hlt">x-ray</span> emission spectra with a single pulse of the Linac Coherent Light Source. The range of applications of SWD spectrometers and traditional multi-SBCA instruments has some overlap, but also is significantly complementary. ?? 2008 American Institute of Physics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/947540','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/947540"><span>A short working distance multiple crystal <span class="hlt">x-ray</span> spectrometer.</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Dickinson, B.; Seidler, G. T.; Webb, Z. W.; Bradley, J. A.; Nagle, K. P.; Heald, S. M.; Gordon, R. A.; Chou, I. M.; Univ. of Washington; Simon Fraser Univ.; U. S. Geological Survey</p> <p>2008-12-01</p> <p>For <span class="hlt">x-ray</span> spot sizes of a few tens of microns or smaller, a millimeter-sized flat analyzer crystal placed {approx}1 cm from the sample will exhibit high energy resolution while subtending a collection solid angle comparable to that of a typical spherically bent crystal analyzer (SBCA) at much larger working distances. Based on this observation and a nonfocusing geometry for the analyzer optic, we have constructed and tested a short working distance (SWD) multicrystal <span class="hlt">x-ray</span> spectrometer. This prototype instrument has a maximum effective collection solid angle of 0.14 sr, comparable to that of 17 SBCA at 1 m working distance. We find good agreement with prior work for measurements of the Mn K{beta} <span class="hlt">x-ray</span> emission and resonant inelastic <span class="hlt">x-ray</span> scattering for MnO, and also for measurements of the <span class="hlt">x-ray</span> absorption near-edge structure for Dy metal using L{sub {alpha}{sub 2}} partial-fluorescence yield detection. We discuss <span class="hlt">future</span> applications at third- and fourth-generation light sources. For concentrated samples, the extremely large collection angle of SWD spectrometers will permit collection of high-resolution <span class="hlt">x-ray</span> emission spectra with a single pulse of the Linac Coherent Light Source. The range of applications of SWD spectrometers and traditional multi-SBCA instruments has some overlap, but also is significantly complementary.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/5871236','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/5871236"><span>Review of soft <span class="hlt">x-ray</span> lasers and their applications</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Skinner, C.H.</p> <p>1991-03-01</p> <p>The emerging technology of soft <span class="hlt">x-ray</span> lasers is in a transition phase between the first laboratory demonstrations of gain and the acceptance of soft <span class="hlt">x-ray</span> lasers as practical tools for novel applications. Current research is focused on several fronts. The operational wavelength range has been extended to the water window'', important for applications in the life sciences. Gain has also been generated with substantially simpler technology (such as a 6J laser) and this augurs well for the commercially availability in the near <span class="hlt">future</span> of soft <span class="hlt">x-ray</span> lasers for a variety of applications. Advanced soft <span class="hlt">x-ray</span> laser concepts are being developed from investigations into ultra-high intensity laser/matter interactions. The first paper a brief historical perspective of <span class="hlt">x-ray</span> microscopy and holography have begun. In this paper a brief historical perspective of <span class="hlt">x-ray</span> laser development will be followed by a review of recent advances in recombination, collisional and photo-pumped systems and applications. A summary of current gain-length performance achieved in laboratories worldwide is presented. Near term prospects for applications to novel fields are discussed. 81 refs., 9 figs., 1 tab.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AAS...21725010C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AAS...21725010C"><span>Characterizing Intergalactic Dust with <span class="hlt">X-ray</span> Halos</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Corrales, Lia; Paerels, F.</p> <p>2011-01-01</p> <p>By estimating the total mass of metals produced through star formation versus the amount of metals locked up in galaxies and intergalactic gas, researchers have concluded that about half of the metals in the intergalactic medium are locked up in dust grains, with Omega 10-5 (Aguirre 1999). Large dust grains are more likely to survive the processes, such as wind and radiation pressure, that enrich the intergalactic medium. Thus intergalactic dust is likely to be gray, leaving no trace of optical reddening that is typical of interstellar dust. We explore the possibility of detecting large ( 1 micron) intergalactic dust grains through small angle <span class="hlt">X-ray</span> scattering. A bright <span class="hlt">X-ray</span> point source, when imaged, will appear surrounded by a halo 10-100 arcseconds wide. The scattering cross section for <span class="hlt">X-rays</span> increases with the grain radius to the fourth power. For a power law distribution of grain sizes, the optical depth of the universe to soft <span class="hlt">X-ray</span> scattering reaches 20% for sources out to z=2. We present models of <span class="hlt">X-ray</span> halos with various grain size distributions and explore the limits a dust-suffused universe places on current and <span class="hlt">future</span> <span class="hlt">X-ray</span> missions, the determination of cosmological parameters, and intergalactic enrichment models.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001Ap%26SS.276..281B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001Ap%26SS.276..281B"><span>The CZT <span class="hlt">X-ray</span> Imager on AXO</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Budtz-Jørgensen, C.; Kuvvetli, I.; Westergaard, N. J.; Jonasson, P.; Reglero, V.; Eyles, C.; Neubert, T.</p> <p>2001-03-01</p> <p>DSRI has initiated a development program of CZT <span class="hlt">X-ray</span> and gamma ray detectors employing strip readout techniques. A dramatic improvement of the energy response was found operating the detectors as so-called drift detectors. For the electronic readout, modern ASIC chips were investigated. Modular design and the low power electronics will make large area detectors using the drift strip method feasible. The performance of a prototype CZT system will be presented and discussed. One such detector system has been proposed for <span class="hlt">future</span> space missions: The <span class="hlt">X-Ray</span> Imager (XRI) on the Atmospheric <span class="hlt">X-ray</span> Observatory (AXO), which is a mission proposed to the Danish Small Satellite Program and is dedicated to observations of <span class="hlt">X-ray</span> generating processes in the Earth's atmosphere. Of special interest will be simultaneous optical and <span class="hlt">X-ray</span> observations of sprites that are flashes appearing directly above an active thunderstorm system. Additional objective is a detailed mapping of the auroral <span class="hlt">X-ray</span> and optical emission. XRI comprises a coded mask and a 20 cm × 40 cm CZT detector array covering an energy range from 5 to 200 keV.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010NatPh...6..163D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010NatPh...6..163D"><span><span class="hlt">X-ray</span> optics: Diamond brilliance</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Durbin, Stephen M.; Colella, Roberto</p> <p>2010-03-01</p> <p>Most materials either absorb or transmit <span class="hlt">X-rays</span>. This is useful for imaging but makes it notoriously difficult to build mirrors for reflective <span class="hlt">X-ray</span> optics. A demonstration of the high <span class="hlt">X-ray</span> reflectivity of diamond could provide a timely solution to make the most of the next generation of free-electron lasers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Amplifiers&pg=7&id=EJ119926','ERIC'); return false;" href="http://eric.ed.gov/?q=Amplifiers&pg=7&id=EJ119926"><span>Student <span class="hlt">X-Ray</span> Fluorescence Experiments</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Fetzer, Homer D.; And Others</p> <p>1975-01-01</p> <p>Describes the experimental arrangement for <span class="hlt">x-ray</span> analysis of samples which involves the following: the radioisotopic <span class="hlt">x-ray</span> disk source; a student-built fluorescence chamber; the energy dispersive <span class="hlt">x-ray</span> detector, linear amplifier and bias supply; and a multichannel pulse height analyzer. (GS)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19670000372','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19670000372"><span>Electron beam parallel <span class="hlt">X-ray</span> generator</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Payne, P.</p> <p>1967-01-01</p> <p>Broad <span class="hlt">X</span> <span class="hlt">ray</span> source produces a highly collimated beam of low energy <span class="hlt">X</span> <span class="hlt">rays</span> - a beam with 2 to 5 arc minutes of divergence at energies between 1 and 6 keV in less than 5 feet. The <span class="hlt">X</span> <span class="hlt">ray</span> beam is generated by electron bombardment of a target from a large area electron gun.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1015982','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1015982"><span>Cryotomography <span class="hlt">x-ray</span> microscopy state</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Le Gros, Mark; Larabell, Carolyn A.</p> <p>2010-10-26</p> <p>An <span class="hlt">x-ray</span> microscope stage enables alignment of a sample about a rotation axis to enable three dimensional tomographic imaging of the sample using an <span class="hlt">x-ray</span> microscope. A heat exchanger assembly provides cooled gas to a sample during <span class="hlt">x-ray</span> microscopic imaging.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://kidshealth.org/en/parents/xray-neck.html','NIH-MEDLINEPLUS'); return false;" href="https://kidshealth.org/en/parents/xray-neck.html"><span><span class="hlt">X-Ray</span> Exam: Neck (For Parents)</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... Habits for TV, Video Games, and the Internet <span class="hlt">X-Ray</span> Exam: Neck KidsHealth > For Parents > <span class="hlt">X-Ray</span> Exam: Neck Print A A A What's in ... español Radiografía: cuello What It Is A neck <span class="hlt">X-ray</span> is a safe and painless test that uses ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.knowyourteeth.com/infobites/abc/article/?abc=X&iid=342&aid=1373','NIH-MEDLINEPLUS'); return false;" href="http://www.knowyourteeth.com/infobites/abc/article/?abc=X&iid=342&aid=1373"><span>Why Do I Need <span class="hlt">X-Rays</span>?</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... to your desktop! more... Why Do I Need <span class="hlt">X-Rays</span>? Article Chapters Why Do I Need <span class="hlt">X-Rays</span>? print full article print this chapter email this article Radiographic, or <span class="hlt">X-ray</span>, examinations provide your dentist with an important tool ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://kidshealth.org/en/parents/xray-femur.html','NIH-MEDLINEPLUS'); return false;" href="https://kidshealth.org/en/parents/xray-femur.html"><span><span class="hlt">X-Ray</span> Exam: Femur (Upper Leg)</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... Habits for TV, Video Games, and the Internet <span class="hlt">X-Ray</span> Exam: Femur (Upper Leg) KidsHealth > For Parents > <span class="hlt">X-Ray</span> Exam: Femur (Upper Leg) Print A A A ... You Have Questions What It Is A femur <span class="hlt">X-ray</span> is a safe and painless test that uses ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://kidshealth.org/en/parents/xray-scoliosis.html','NIH-MEDLINEPLUS'); return false;" href="https://kidshealth.org/en/parents/xray-scoliosis.html"><span><span class="hlt">X-Ray</span> Exam: Scoliosis (For Parents)</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... Habits for TV, Video Games, and the Internet <span class="hlt">X-Ray</span> Exam: Scoliosis KidsHealth > For Parents > <span class="hlt">X-Ray</span> Exam: Scoliosis Print A A A What's in ... You Have Questions What It Is A scoliosis <span class="hlt">X-ray</span> is a relatively safe and painless test that ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://kidshealth.org/en/parents/xray-c-spine.html','NIH-MEDLINEPLUS'); return false;" href="https://kidshealth.org/en/parents/xray-c-spine.html"><span><span class="hlt">X-Ray</span> Exam: Cervical Spine</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... to 2-Year-Old <span class="hlt">X-Ray</span> Exam: Cervical Spine KidsHealth > For Parents > <span class="hlt">X-Ray</span> Exam: Cervical Spine Print A A A What's in this article? ... Radiografía: columna cervical What It Is A cervical spine <span class="hlt">X-ray</span> is a safe and painless test ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://images.nasa.gov/#/details-PIA21089.html','SCIGOVIMAGE-NASA'); return false;" href="https://images.nasa.gov/#/details-PIA21089.html"><span>Supernova SN 2014C <span class="hlt">X-ray</span></span></a></p> <p><a target="_blank" href="https://images.nasa.gov/">NASA Image and Video Library</a></p> <p></p> <p>2017-01-24</p> <p>This image from NASA's Chandra <span class="hlt">X-ray</span> Observatory shows spiral galaxy NGC 7331, center, in a three-color <span class="hlt">X-ray</span> image. Red, green and blue colors are used for low, medium and high-energy <span class="hlt">X-rays</span>, respectively. An unusual supernova called SN 2014C has been spotted in this galaxy. http://photojournal.jpl.nasa.gov/catalog/PIA21089</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_24 --> <div id="page_25" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="481"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=Amplifiers&pg=7&id=EJ119926','ERIC'); return false;" href="https://eric.ed.gov/?q=Amplifiers&pg=7&id=EJ119926"><span>Student <span class="hlt">X-Ray</span> Fluorescence Experiments</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Fetzer, Homer D.; And Others</p> <p>1975-01-01</p> <p>Describes the experimental arrangement for <span class="hlt">x-ray</span> analysis of samples which involves the following: the radioisotopic <span class="hlt">x-ray</span> disk source; a student-built fluorescence chamber; the energy dispersive <span class="hlt">x-ray</span> detector, linear amplifier and bias supply; and a multichannel pulse height analyzer. (GS)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://kidshealth.org/en/parents/xray-c-spine.html','NIH-MEDLINEPLUS'); return false;" href="http://kidshealth.org/en/parents/xray-c-spine.html"><span><span class="hlt">X-Ray</span> Exam: Cervical Spine</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... to 2-Year-Old <span class="hlt">X-Ray</span> Exam: Cervical Spine KidsHealth > For Parents > <span class="hlt">X-Ray</span> Exam: Cervical Spine A A A What's in this article? What ... Radiografía: columna cervical What It Is A cervical spine <span class="hlt">X-ray</span> is a safe and painless test ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/5485201','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/5485201"><span>Center for <span class="hlt">X-ray</span> Optics, 1988</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Not Available</p> <p>1989-04-01</p> <p>This report briefly reviews the following topics: soft-<span class="hlt">x-ray</span> imaging; reflective optics for hard <span class="hlt">x-rays</span>; coherent XUV sources; spectroscopy with <span class="hlt">x-rays</span>; detectors for coronary artery imaging; synchrotron-radiation optics; and support for the advanced light source.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010PhDT........98H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010PhDT........98H"><span>Hard <span class="hlt">x-ray</span> phase contrastmicroscopy - techniques and applications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Holzner, Christian</p> <p></p> <p>In 1918, Einstein provided the first description of the nature of the refractive index for <span class="hlt">X-rays</span>, showing that phase contrast effects are significant. A century later, most <span class="hlt">x-ray</span> microscopy and nearly all medical imaging remains based on absorption contrast, even though phase contrast offers orders of magnitude improvements in contrast and reduced radiation exposure at multi-keV <span class="hlt">x-ray</span> energies. The work presented is concerned with developing practical and quantitative methods of phase contrast for <span class="hlt">x-ray</span> microscopy. A theoretical framework for imaging in phase contrast is put forward; this is used to obtain quantitative images in a scanning microscope using a segmented detector, and to correct for artifacts in a commercial phase contrast <span class="hlt">x-ray</span> nano-tomography system. The principle of reciprocity between scanning and full-field microscopes is then used to arrive at a novel solution: Zernike contrast in a scanning microscope. These approaches are compared on a theoretical and experimental basis in direct connection with applications using multi-keV <span class="hlt">x-ray</span> microscopes at the Advanced Photon Source at Argonne National Laboratory. Phase contrast provides the best means to image mass and ultrastructure of light elements that mainly constitute biological matter, while stimulated <span class="hlt">x-ray</span> fluorescence provides high sensitivity for studies of the distribution of heavier trace elements, such as metals. These approaches are combined in a complementary way to yield quantitative maps of elemental concentration from 2D images, with elements placed in their ultrastructural context. The combination of <span class="hlt">x-ray</span> fluorescence and phase contrast poses an ideal match for routine, high resolution tomographic imaging of biological samples in the <span class="hlt">future</span>. The presented techniques and demonstration experiments will help pave the way for this development.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22121636','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22121636"><span>Data needs for <span class="hlt">X-ray</span> astronomy satellites</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kallman, T.</p> <p>2013-07-11</p> <p>I review the current status of atomic data for <span class="hlt">X-ray</span> astronomy satellites. This includes some of the astrophysical issues which can be addressed, current modeling and analysis techniques, computational tools, the limitations imposed by currently available atomic data, and the validity of standard assumptions. I also discuss the <span class="hlt">future</span>: challenges associated with <span class="hlt">future</span> missions and goals for atomic data collection.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADD018276','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADD018276"><span>Mobile <span class="hlt">X-Ray</span> Unit.</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1996-10-28</p> <p>anode 8 surrounded by a coaxial annulus of stainless steel mesh which 9 serves as the cathode, control electronics, and a plurality of 10 spark gap...34Siemens-tube" configuration. More 7 particularly, the <span class="hlt">X-ray</span> tube 16 has a conical copper/tungsten 8 anode 28, and a stainless steel mesh punched to...160 and 162 each having a typical diameter of 14 2.75 inches. The conflat flanges 160 and 162 are mated to a 15 stainless steel tube 164 having a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015SPIE.9603E..1SG','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015SPIE.9603E..1SG"><span>Design and implementation of an <span class="hlt">x-ray</span> reflectometer system for testing <span class="hlt">x-ray</span> optics coatings</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gurgew, Danielle N.; Broadway, David; Gubarev, Mikhail; Ramsey, Brian</p> <p>2015-09-01</p> <p>We have developed an <span class="hlt">X-ray</span> reflectometer (XRR) system for the characterization of various soft and hard <span class="hlt">X-ray</span> optic coatings being developed at Marshall Space Flight Center. The XRR system generates <span class="hlt">X-ray</span> radiation with a highoutput Rigaku rotating anode source (RAS), operational at a voltage range of 5 - 35 kV, a current range of 10-150 mA. A series of precision slits, adjustable down to approximately 25 micrometers, positioned in the beam path limit the extent of the <span class="hlt">x-ray</span> beam and control the resolution of the XRR measurement while a goniometer consisting of two precision rotary stages controls the angular position of the coating sample and <span class="hlt">X-ray</span> detector with respect to the beam. With the high count rate capability of the RAS, a very-high-speed silicon drift detector, the Amptek Fast Silicon Drift Detector (SDD), is implemented to achieve good count rate efficiency and improve reflectivity measurements of coatings at larger graze angles. The coating sample can be adjusted using a series of linear and tipping stages to perfectly align the center of the sample with the center of the incident <span class="hlt">X-ray</span> beam. These stages in conjunction with the goniometer components are integrated through original control software resulting in full automation of the XRR system. We will show some initial XRR measurements of both single and multilayer coatings made with this system. These results and <span class="hlt">future</span> measurements are used to characterize potential <span class="hlt">X-ray</span> optic coatings culminating in the production of highly reflective coatings operational at a large range of <span class="hlt">X-ray</span> energies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16021936','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16021936"><span>Global and <span class="hlt">planetary</span> health: teaching as if the <span class="hlt">future</span> matters.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Johnston, Nancy; Rogers, Martha; Cross, Nadine; Sochan, Anne</p> <p>2005-01-01</p> <p>If nursing, along with other health professions, is to be able to critique national and international health policy and be equipped to address the global and <span class="hlt">planetary</span> dimensions of health, the conceptual horizons of our educational and research enterprises will need to be expanded. Not only are nursing curricula needed that address such concepts as "health for all" and "environmental sustainability," but new pedagogies are required that engage students deeply and call them to socially and globally responsible ways-of-being. This article describes teaching and learning in a course that situates health in a global and environmental context and calls forth new personal and professional meanings.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/877975','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/877975"><span><span class="hlt">X-ray</span> Spectroscopy of Cooling Cluster</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Peterson, J.R.; Fabian, A.C.; /Cambridge U., Inst. of Astron.</p> <p>2006-01-17</p> <p>We review the <span class="hlt">X-ray</span> spectra of the cores of clusters of galaxies. Recent high resolution <span class="hlt">X-ray</span> spectroscopic observations have demonstrated a severe deficit of emission at the lowest <span class="hlt">X-ray</span> temperatures as compared to that expected from simple radiative cooling models. The same observations have provided compelling evidence that the gas in the cores is cooling below half the maximum temperature. We review these results, discuss physical models of cooling clusters, and describe the <span class="hlt">X-ray</span> instrumentation and analysis techniques used to make these observations. We discuss several viable mechanisms designed to cancel or distort the expected process of <span class="hlt">X-ray</span> cluster cooling.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20080004973','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20080004973"><span>Atmospheric electron <span class="hlt">x-ray</span> spectrometer</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Feldman, Jason E. (Inventor); George, Thomas (Inventor); Wilcox, Jaroslava Z. (Inventor)</p> <p>2002-01-01</p> <p>The present invention comprises an apparatus for performing in-situ elemental analyses of surfaces. The invention comprises an atmospheric electron <span class="hlt">x-ray</span> spectrometer with an electron column which generates, accelerates, and focuses electrons in a column which is isolated from ambient pressure by a:thin, electron transparent membrane. After passing through the membrane, the electrons impinge on the sample in atmosphere to generate characteristic <span class="hlt">x-rays</span>. An <span class="hlt">x-ray</span> detector, shaping amplifier, and multi-channel analyzer are used for <span class="hlt">x-ray</span> detection and signal analysis. By comparing the resultant data to known <span class="hlt">x-ray</span> spectral signatures, the elemental composition of the surface can be determined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15121706','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15121706"><span><span class="hlt">X-ray</span> imaging for palaeontology.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hohenstein, P</p> <p>2004-05-01</p> <p>Few may be aware that <span class="hlt">X-ray</span> imaging is used in palaeontology and has been used since as early as 1896. The <span class="hlt">X-raying</span>, preparation and exposure of Hunsrück slate fossils are described. Hospital <span class="hlt">X-ray</span> machines are used by the author in his work. An <span class="hlt">X-ray</span> is vital to provide evidence that preparation of a slate is worthwhile as well as to facilitate preparation even if there is little external sign of what lies within. The beauty of the <span class="hlt">X-ray</span> exposure is an added bonus.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/870431','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/870431"><span><span class="hlt">X-ray</span> transmissive debris shield</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Spielman, Rick B.</p> <p>1996-01-01</p> <p>An <span class="hlt">X-ray</span> debris shield for use in <span class="hlt">X-ray</span> lithography that is comprised of an <span class="hlt">X-ray</span> window having a layer of low density foam exhibits increased longevity without a substantial increase in exposure time. The low density foam layer serves to absorb the debris emitted from the <span class="hlt">X-ray</span> source and attenuate the shock to the window so as to reduce the chance of breakage. Because the foam is low density, the <span class="hlt">X-rays</span> are hardly attenuated by the foam and thus the exposure time is not substantially increased.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/238067','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/biblio/238067"><span><span class="hlt">X-ray</span> transmissive debris shield</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Spielman, R.B.</p> <p>1996-05-21</p> <p>An <span class="hlt">X-ray</span> debris shield for use in <span class="hlt">X-ray</span> lithography that is comprised of an <span class="hlt">X-ray</span> window having a layer of low density foam exhibits increased longevity without a substantial increase in exposure time. The low density foam layer serves to absorb the debris emitted from the <span class="hlt">X-ray</span> source and attenuate the shock to the window so as to reduce the chance of breakage. Because the foam is low density, the <span class="hlt">X-rays</span> are hardly attenuated by the foam and thus the exposure time is not substantially increased.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1349886','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1349886"><span>Method for spatially modulating <span class="hlt">X-ray</span> pulses using MEMS-based <span class="hlt">X-ray</span> optics</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Lopez, Daniel; Shenoy, Gopal; Wang, Jin; Walko, Donald A.; Jung, Il-Woong; Mukhopadhyay, Deepkishore</p> <p>2015-03-10</p> <p>A method and apparatus are provided for spatially modulating <span class="hlt">X-rays</span> or <span class="hlt">X-ray</span> pulses using microelectromechanical systems (MEMS) based <span class="hlt">X-ray</span> optics. A torsionally-oscillating MEMS micromirror and a method of leveraging the grazing-angle reflection property are provided to modulate <span class="hlt">X-ray</span> pulses with a high-degree of controllability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002SPIE.4782....1F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002SPIE.4782....1F"><span>Challenges for Synchrotron <span class="hlt">X-Ray</span> Optics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Freund, Andreas K.</p> <p>2002-12-01</p> <p>It is the task of <span class="hlt">x-ray</span> optics to adapt the raw beam generated by modern sources such as synchrotron storage rings to a great variety of experimental requirements in terms of intensity, spot size, polarization and other parameters. The very high quality of synchrotron radiation (source size of a few microns and beam divergence of a few micro-radians) and the extreme <span class="hlt">x-ray</span> flux (power of several hundred Watts in a few square mm) make this task quite difficult. In particular the heat load aspect is very important in the conditioning process of the brute <span class="hlt">x-ray</span> power to make it suitable for being used on the experimental stations. Cryogenically cooled silicon crystals and water-cooled diamond crystals can presently fulfill this task, but limits will soon be reached and new schemes and materials must be envisioned. A major tendency of instrument improvement has always been to concentrate more photons into a smaller spot utilizing a whole variety of focusing devices such as Fresnel zone plates, refractive lenses and systems based on bent surfaces, for example, Kirkpatrick-Baez systems. Apart from the resistance of the sample, the ultimate limits are determined by the source size and strength on one side, by materials properties, cooling, mounting and bending schemes on the other side, and fundamentally by the diffraction process. There is also the important aspect of coherence that can be both a nuisance and a blessing for the experiments, in particular for imaging techniques. Its conservation puts additional constraints on the quality of the optical elements. The overview of the present challenges includes the properties of present and also mentions aspects of <span class="hlt">future</span> <span class="hlt">x-ray</span> sources such as the "ultimate" storage ring and free electron lasers. These challenges range from the thermal performances of monochromators to the surface quality of mirrors, from coherence preservation of modern multilayers to short pulse preservation by crystals, and from micro- and nano</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19930002415','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19930002415"><span>The search for life's origins: Progress and <span class="hlt">future</span> directions in <span class="hlt">planetary</span> biology and chemical evolution</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1990-01-01</p> <p>The current state is reviewed of the study of chemical evolution and <span class="hlt">planetary</span> biology and the probable <span class="hlt">future</span> is discussed of the field, at least for the near term. To this end, the report lists the goals and objectives of <span class="hlt">future</span> research and makes detailed, comprehensive recommendations for accomplishing them, emphasizing those issues that were inadequately discussed in earlier Space Studies Board reports.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1999xmm..pres...19.','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1999xmm..pres...19."><span>Lifting the veil on the <span class="hlt">X-ray</span> universe</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p></p> <p>1999-11-01</p> <p>ESA's <span class="hlt">X-ray</span> Multi Mirror mission - XMM - is the second Cornerstone in ESA's Long Term Scientific Programme (*). This new <span class="hlt">X-ray</span> space telescope promises even more discoveries. With the large collecting area of its mirrors and the high sensitivity of its cameras, XMM is expected to increase radically our understanding of high-energy sources - clues to a mysterious past, and keys to understanding the <span class="hlt">future</span> of the Universe. 174 wafer-thin <span class="hlt">X-ray</span> mirrors <span class="hlt">X-rays</span> coming from celestial objects are highly energetic and elusive. They can best be measured and studied after focusing a sufficient number upon sensitive detectors. To achieve this, XMM's Mirror Modules have been given a gargantuan appetite for <span class="hlt">X-rays</span>. The space observatory combines three barrel-shaped telescope modules. In each are nested 58 wafer-thin concentric mirror shells highly polished and subtly shaped. Passing through at an extremely shallow angle, the so-called "grazing incidence", the <span class="hlt">X-rays</span> will be beamed to the science instruments situated on the focal plane at the other extremity of the satellite. The three mirror modules have a total mirror surface of over 120m2 - practically the size of a tennis court.. The collecting power of XMM's three telescopes is the greatest ever seen on an <span class="hlt">X-ray</span> space mission, many times more than the most recently launched <span class="hlt">X-ray</span> satellite. The design and assembly of the mirror modules, their testing for operation in space and their precise calibration constitute one of the greatest achievements of the XMM programme. The flimsy mirror shells, with their gold reflective surface on a nickel backing, were made by replication like carbon copies from master moulds. They were shaped to an accuracy of a thousandth of a millimetre, and then polished to a smoothness a thousand times better than that. Packaged one within another like Russian dolls, each mirror was focused and centred with respect to its neighbour to an accuracy of 25 microns - a quarter of the width of a human hair</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21371070','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21371070"><span>{sup 30}S Beam Development and <span class="hlt">X-ray</span> Bursts</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kahl, D.; Kubono, S.; Binh, D. N.; Hashimoto, T.; Hayakawa, S.; Kurihara, Y.; Ohshiro, Y.; Yamaguchi, H.; Chen, A. A.; Chen, J.; Setoodeh nia, K.; Kaji, D.; Nishimura, S.; Kim, A.; Lee, N. H.; Wakabayashi, Y.</p> <p>2010-03-01</p> <p>Over the past three years, we have worked on developing a well-characterized {sup 30}S radioactive beam to be used in a <span class="hlt">future</span> experiment aiming to directly measure to extrapolate the {sup 30}S(alpha,p) stellar reaction rate within the Gamow window of Type I <span class="hlt">X-ray</span> bursts. The importance of the {sup 30}S(alpha,p) reaction to <span class="hlt">X-ray</span> bursts is discussed. Given the astrophysical motivation, the successful results of and challenges involved in the production of a low-energy {sup 30}S beam are detailed. Finally, an overview of our <span class="hlt">future</span> plans regarding this on-going project are presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/870098','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/870098"><span><span class="hlt">X-ray</span> lithography using holographic images</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Howells, Malcolm R.; Jacobsen, Chris</p> <p>1995-01-01</p> <p>A non-contact <span class="hlt">X-ray</span> projection lithography method for producing a desired <span class="hlt">X-ray</span> image on a selected surface of an <span class="hlt">X-ray</span>-sensitive material, such as photoresist material on a wafer, the desired <span class="hlt">X-ray</span> image having image minimum linewidths as small as 0.063 .mu.m, or even smaller. A hologram and its position are determined that will produce the desired image on the selected surface when the hologram is irradiated with <span class="hlt">X-rays</span> from a suitably monochromatic <span class="hlt">X-ray</span> source of a selected wavelength .lambda.. On-axis <span class="hlt">X-ray</span> transmission through, or off-axis <span class="hlt">X-ray</span> reflection from, a hologram may be used here, with very different requirements for monochromaticity, flux and brightness of the <span class="hlt">X-ray</span> source. For reasonable penetration of photoresist materials by <span class="hlt">X-rays</span> produced by the <span class="hlt">X-ray</span> source, the wavelength X, is preferably chosen to be no more than 13.5 nm in one embodiment and more preferably is chosen in the range 1-5 nm in the other embodiment. A lower limit on linewidth is set by the linewidth of available microstructure writing devices, such as an electron beam.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19910013717','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19910013717"><span><span class="hlt">X</span> <span class="hlt">ray</span> imaging microscope for cancer research</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hoover, Richard B.; Shealy, David L.; Brinkley, B. R.; Baker, Phillip C.; Barbee, Troy W., Jr.; Walker, Arthur B. C., Jr.</p> <p>1991-01-01</p> <p>The NASA technology employed during the Stanford MSFC LLNL Rocket <span class="hlt">X</span> <span class="hlt">Ray</span> Spectroheliograph flight established that doubly reflecting, normal incidence multilayer optics can be designed, fabricated, and used for high resolution <span class="hlt">x</span> <span class="hlt">ray</span> imaging of the Sun. Technology developed as part of the MSFC <span class="hlt">X</span> <span class="hlt">Ray</span> Microscope program, showed that high quality, high resolution multilayer <span class="hlt">x</span> <span class="hlt">ray</span> imaging microscopes are feasible. Using technology developed at Stanford University and at the DOE Lawrence Livermore National Laboratory (LLNL), Troy W. Barbee, Jr. has fabricated multilayer coatings with near theoretical reflectivities and perfect bandpass matching for a new rocket borne solar observatory, the Multi-Spectral Solar Telescope Array (MSSTA). Advanced Flow Polishing has provided multilayer mirror substrates with sub-angstrom (rms) smoothnesss for the astronomical <span class="hlt">x</span> <span class="hlt">ray</span> telescopes and <span class="hlt">x</span> <span class="hlt">ray</span> microscopes. The combination of these important technological advancements has paved the way for the development of a Water Window Imaging <span class="hlt">X</span> <span class="hlt">Ray</span> Microscope for cancer research.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_25 --> <center> <div class="footer-extlink text-muted"><small>Some links on this page may take you to non-federal websites. Their policies may differ from this site.</small> </div> </center> <div id="footer-wrapper"> <div class="footer-content"> <div id="footerOSTI" class=""> <div class="row"> <div class="col-md-4 text-center col-md-push-4 footer-content-center"><small><a href="http://www.science.gov/disclaimer.html">Privacy and Security</a></small> <div class="visible-sm visible-xs push_footer"></div> </div> <div class="col-md-4 text-center col-md-pull-4 footer-content-left"> <img src="https://www.osti.gov/images/DOE_SC31.png" alt="U.S. Department of Energy" usemap="#doe" height="31" width="177"><map style="display:none;" name="doe" id="doe"><area shape="rect" coords="1,3,107,30" href="http://www.energy.gov" alt="U.S. Deparment of Energy"><area shape="rect" coords="114,3,165,30" href="http://www.science.energy.gov" alt="Office of Science"></map> <a ref="http://www.osti.gov" style="margin-left: 15px;"><img src="https://www.osti.gov/images/footerimages/ostigov53.png" alt="Office of Scientific and Technical Information" height="31" width="53"></a> <div class="visible-sm visible-xs push_footer"></div> </div> <div class="col-md-4 text-center footer-content-right"> <a href="http://www.science.gov"><img src="https://www.osti.gov/images/footerimages/scigov77.png" alt="science.gov" height="31" width="98"></a> <a href="http://worldwidescience.org"><img src="https://www.osti.gov/images/footerimages/wws82.png" alt="WorldWideScience.org" height="31" width="90"></a> </div> </div> </div> </div> </div> <p><br></p> </div><!-- container --> <script type="text/javascript"><!-- // var lastDiv = ""; function showDiv(divName) { // hide last div if (lastDiv) { document.getElementById(lastDiv).className = "hiddenDiv"; } //if value of the box is not nothing and an object with that name exists, then change the class if (divName && document.getElementById(divName)) { document.getElementById(divName).className = "visibleDiv"; lastDiv = divName; } } //--> </script> <script> /** * Function that tracks a click on an outbound link in Google Analytics. * This function takes a valid URL string as an argument, and uses that URL string * as the event label. */ var trackOutboundLink = function(url,collectionCode) { try { h = window.open(url); setTimeout(function() { ga('send', 'event', 'topic-page-click-through', collectionCode, url); }, 1000); } catch(err){} }; </script> <!-- Google Analytics --> <script> (function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){ (i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o), m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m) })(window,document,'script','//www.google-analytics.com/analytics.js','ga'); ga('create', 'UA-1122789-34', 'auto'); ga('send', 'pageview'); </script> <!-- End Google Analytics --> <script> showDiv('page_1') </script> </body> </html>