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Sample records for soft x-ray synchrotron

  1. Actinide science with soft x-ray synchrotron radiation

    NASA Astrophysics Data System (ADS)

    Shuh, David K.

    2000-07-01

    The primary methods for the experimental investigation of actinide materials in the VUV/soft x-ray region are the complementary photoelectron spectroscopies, near-edge x-ray absorption fine structure (NEXAFS), and x-ray emission spectroscopy (XES) techniques. Resonant photoemission techniques capable of resolving the 5f electron contributions to actinide bonding along with angle-resolving measurements for band structure and surface structure determinations, have clear and immediate applications. Venerable angle-integrating core and valence band photoelectron spectroscopy are valuable for characterization and analytical purposes. Combined with results from NEXAFS measurements, these techniques will provide the information needed to develop improved understandings of the electronic structure of actinide materials and their surface chemistries/physics.

  2. Optical systems for synchrotron radiation: lecture 4. Soft x-ray imaging systems

    SciTech Connect

    Howells, M.R.

    1986-04-01

    The history and present techniques of soft x-ray imaging are reviewed briefly. The physics of x-ray imaging is described, including the temporal and spatial coherence of x-ray sources. Particular technologies described are: contact x-ray microscopy, zone plate imaging, scanned image zone plate microscopy, scanned image reflection microscopy, and soft x-ray holography and diffraction. (LEW)

  3. Real world issues for the new soft x-ray synchrotron sources

    SciTech Connect

    Kincaid, B.M.

    1991-05-01

    A new generation of synchrotron radiation light sources covering the VUV, soft x-ray and hard x-ray spectral regions is under construction in several countries. They are designed specifically to use periodic magnetic undulators and low-emittance electron or positron beams to produce high-brightness near-diffraction-limited synchrotron radiation beams. An introduction to the properties of undulator radiation is followed by a discussion of some of the challenges to be faced at the new facilities. Examples of predicted undulator output from the Advanced Light Source, a third generation 1--2 GeV storage ring optimized for undulator use, are used to highlight differences from present synchrotron radiation sources, including high beam power, partial coherence, harmonics, and other unusual spectral and angular properties of undulator radiation. 8 refs., 2 figs.

  4. A magnetizing system for dichroism measurements in soft x-ray emission excited by synchrotron radiation

    SciTech Connect

    Dallera, C.; Ghiringhelli, G.; Braicovich, L.

    1996-02-01

    We present the design and performance of a magnetic circuit suitable for magnetizing solid samples in the measurements of soft x-ray emission dichroism excited by synchrotron radiation. The system allows a variety of samples to be magnetized and satisfies the rather stringent geometrical constraints due to the need for minimizing the effect of photon self-absorption by the sample. The magnetic circuit is ultrahigh vacuum compatible, can reach about 2800 G, and allows fine adjustment of sample position. {copyright} {ital 1996 American Institute of Physics.}

  5. Development of soft X-ray polarized light beamline on Indus-2 synchrotron radiation source

    SciTech Connect

    Phase, D. M. Gupta, Mukul Potdar, S. Behera, L. Sah, R. Gupta, Ajay

    2014-04-24

    This article describes the development of a soft x-ray beamline on a bending magnet source of Indus-2 storage ring (2.5 GeV) and some preliminary results of x-ray absorption spectroscopy (XAS) measurements using the same. The beamline layout is based on a spherical grating monochromator. The beamline is able to accept synchrotron radiation from the bending magnet port BL-1 of the Indus-2 ring with a wide solid angle. The large horizontal and vertical angular acceptance contributes to high photon flux and selective polarization respectively. The complete beamline is tested for ultrahigh vacuum (UHV) ∼ 10{sup −10} mbar. First absorption spectrum was obtained on HOPG graphite foil. Our performance test indicates that modest resolving power has been achieved with adequate photon flux to carry out various absorption experiments.

  6. Development of optical choppers for time-resolved measurements at soft X-ray synchrotron radiation beamlines.

    PubMed

    Osawa, Hitoshi; Ohkochi, Takuo; Fujisawa, Masami; Kimura, Shigeru; Kinoshita, Toyohiko

    2017-05-01

    Two types of optical choppers for time-resolved measurements at synchrotron radiation soft X-ray beamlines have been developed. One type uses an air-spindle-type rotation mechanism with a two-stage differential pumping system to maintain the ultra-high vacuum of the X-ray beamline, and the other uses a magnetic bearing. Both can be installed at the soft X-ray beamlines at SPring-8, greatly improving the accessibility of pump-and-probe spectroscopy. The combination of X-ray chopper and pump-and-probe photoemission electron microscope at SPring-8 provides drastic improvements in signal-to-noise ratio and resolution compared with techniques using high-voltage gating of channel plate detectors. The choppers have the capability to be used not only at synchrotron radiation facilities but also at other types of soft X-ray and VUV beamlines.

  7. Synchrotron Vacuum Ultraviolet Light and Soft X-Ray Radiation Effects on Aluminized Teflon FEP Investigated

    NASA Technical Reports Server (NTRS)

    Dever, Joyce A.; Townsend, Jacqueline A.; Gaier, James R.; Jalics, Alice I.

    1999-01-01

    Since the Hubble Space Telescope (HST) was deployed in low Earth orbit in April 1990, two servicing missions have been conducted to upgrade its scientific capabilities. Minor cracking of second-surface metalized Teflon FEP (DuPont; fluorinated ethylene propylene) surfaces from multilayer insulation (MLI) was first observed upon close examination of samples with high solar exposure retrieved during the first servicing mission, which was conducted 3.6 years after deployment. During the second HST servicing mission, 6.8 years after deployment, astronaut observations and photographic documentation revealed significant cracks in the Teflon FEP layer of the MLI on both the solar- and anti-solar-facing surfaces of the telescope. NASA Goddard Space Flight Center directed the efforts of the Hubble Space Telescope MLI Failure Review Board, whose goals included identifying the low-Earth-orbit environmental constituent(s) responsible for the cracking and embrittling of Teflon FEP which was observed during the second servicing mission. The NASA Lewis Research Center provided significant support to this effort. Because soft x-ray radiation from solar flares had been considered as a possible cause for the degradation of the mechanical properties of Teflon FEP (ref. 1), the effects of soft xray radiation and vacuum ultraviolet light on Teflon FEP were investigated. In this Lewisled effort, samples of Teflon FEP with a 100-nm layer of vapor-deposited aluminum (VDA) on the backside were exposed to synchrotron radiation of various vacuum ultraviolet and soft x-ray wavelengths between 18 nm (69 eV) and 0.65 nm (1900 eV). Synchrotron radiation exposures were conducted using the National Synchrotron Light Source at Brookhaven National Laboratory. Samples of FEP/VDA were exposed with the FEP surface facing the synchrotron beam. Doses and fluences were compared with those estimated for the 20-yr Hubble Space Telescope mission.

  8. Time-resolved soft x-ray absorption setup using multi-bunch operation modes at synchrotrons.

    PubMed

    Stebel, L; Malvestuto, M; Capogrosso, V; Sigalotti, P; Ressel, B; Bondino, F; Magnano, E; Cautero, G; Parmigiani, F

    2011-12-01

    Here, we report on a novel experimental apparatus for performing time-resolved soft x-ray absorption spectroscopy in the sub-ns time scale using non-hybrid multi-bunch mode synchrotron radiation. The present setup is based on a variable repetition rate Ti:sapphire laser (pump pulse) synchronized with the ~500 MHz x-ray synchrotron radiation bunches and on a detection system that discriminates and singles out the significant x-ray photon pulses by means of a custom made photon counting unit. The whole setup has been validated by measuring the time evolution of the L(3) absorption edge during the melting and the solidification of a Ge single crystal irradiated by an intense ultrafast laser pulse. These results pave the way for performing synchrotron time-resolved experiments in the sub-ns time domain with variable repetition rate exploiting the full flux of the synchrotron radiation.

  9. Time-resolved soft x-ray absorption setup using multi-bunch operation modes at synchrotrons

    SciTech Connect

    Stebel, L.; Sigalotti, P.; Ressel, B.; Cautero, G.; Malvestuto, M.; Capogrosso, V.; Bondino, F.; Magnano, E.; Parmigiani, F.

    2011-12-15

    Here, we report on a novel experimental apparatus for performing time-resolved soft x-ray absorption spectroscopy in the sub-ns time scale using non-hybrid multi-bunch mode synchrotron radiation. The present setup is based on a variable repetition rate Ti:sapphire laser (pump pulse) synchronized with the {approx}500 MHz x-ray synchrotron radiation bunches and on a detection system that discriminates and singles out the significant x-ray photon pulses by means of a custom made photon counting unit. The whole setup has been validated by measuring the time evolution of the L{sub 3} absorption edge during the melting and the solidification of a Ge single crystal irradiated by an intense ultrafast laser pulse. These results pave the way for performing synchrotron time-resolved experiments in the sub-ns time domain with variable repetition rate exploiting the full flux of the synchrotron radiation.

  10. Time-resolved soft x-ray absorption setup using multi-bunch operation modes at synchrotrons

    NASA Astrophysics Data System (ADS)

    Stebel, L.; Malvestuto, M.; Capogrosso, V.; Sigalotti, P.; Ressel, B.; Bondino, F.; Magnano, E.; Cautero, G.; Parmigiani, F.

    2011-12-01

    Here, we report on a novel experimental apparatus for performing time-resolved soft x-ray absorption spectroscopy in the sub-ns time scale using non-hybrid multi-bunch mode synchrotron radiation. The present setup is based on a variable repetition rate Ti:sapphire laser (pump pulse) synchronized with the ˜500 MHz x-ray synchrotron radiation bunches and on a detection system that discriminates and singles out the significant x-ray photon pulses by means of a custom made photon counting unit. The whole setup has been validated by measuring the time evolution of the L3 absorption edge during the melting and the solidification of a Ge single crystal irradiated by an intense ultrafast laser pulse. These results pave the way for performing synchrotron time-resolved experiments in the sub-ns time domain with variable repetition rate exploiting the full flux of the synchrotron radiation.

  11. Synchrotron soft X-ray absorption spectroscopy study of carbon and silicon nanostructures for energy applications.

    PubMed

    Zhong, Jun; Zhang, Hui; Sun, Xuhui; Lee, Shuit-Tong

    2014-12-10

    Carbon and silicon materials are two of the most important materials involved in the history of the science and technology development. In the last two decades, C and Si nanoscale materials, e.g., carbon nanotubes, graphene, and silicon nanowires, and quantum dots, have also emerged as the most interesting nanomaterials in nanoscience and nanotechnology for their myriad promising applications such as for electronics, sensors, biotechnology, etc. In particular, carbon and silicon nanostructures are being utilized in energy-related applications such as catalysis, batteries, solar cells, etc., with significant advances. Understanding of the nature of surface and electronic structures of nanostructures plays a key role in the development and improvement of energy conversion and storage nanosystems. Synchrotron soft X-ray absorption spectroscopy (XAS) and related techniques, such as X-ray emission spectroscopy (XES) and scanning transmission X-ray microscopy (STXM), show unique capability in revealing the surface and electronic structures of C and Si nanomaterials. In this review, XAS is demonstrated as a powerful technique for probing chemical bonding, the electronic structure, and the surface chemistry of carbon and silicon nanomaterials, which can greatly enhance the fundamental understanding and also applicability of these nanomaterials in energy applications. The focus is on the unique advantages of XAS as a complementary tool to conventional microscopy and spectroscopy for effectively providing chemical and structural information about carbon and silicon nanostructures. The employment of XAS for in situ, real-time study of property evolution of C and Si nanostructures to elucidate the mechanisms in energy conversion or storage processes is also discussed. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. YB66 as a new soft x-ray monochromator for synchrotron radiation (abstract)

    NASA Astrophysics Data System (ADS)

    Rek, Z.; Wong, Joe; Tanaka, T.; Shimkaveg, G.; Eckart, M.

    1992-01-01

    YB66, a complex binary semiconducting compound with a cubic crystal structure and a lattice parameter of 23.44 Å, is potentially a very good candidate for monochromatization of soft x-ray synchrotron radiation. The features such as: a large interatomic spacing, lack of absorption edges by the constituent elements in the region 1-2 keV, very narrow intrinsic rocking curves for (400) and (222) reflections and good thermal and mechanical properties make the material very useful. Using the known structure factors for the (400) and (222) reflections, having 2d values of 11.76 and 13.53 Å, respectively, their rocking curves have been calculated and are shown [J. Wang, G. Shimkaveg, W. Goldstein, M. Eckart, T. Tanaka, Z. Rek, H. Tompkins, Nucl. Instrum. Methods A 291, 243 (1990)] to be comparable to or better than that of beryl (101¯0). A novel indirect heating floating zone method for growing large size crystals was used by Tanaka and his coworkers in Japan [T. Tanaka, S. Otani, and Y. Ishizawa, J. Cryst. Growth 73, 31 (1985)]. Numerous modifications of this technique and double-zone passes were applied to reduce sub grain structure and lattice deformations. The crystalline perfection and absence of defects is critical to obtaining high energy resolution and good crystal reflectivity. Crystals large enough to accept 1 mrad of radiation, with growth direction [100] and [110] were grown. Rocking curve measurements, etch pit density, and x-ray white beam topography are used to characterize the quality of these crystals as a function of some critical growth parameters. Most crystals exhibit the existence of sub grain boundaries. Areas perfect enough were observed to give ˜ 0.5 eV energy resolution. Recent experiments in crystal growth, results of crystals characterization, and comparison with theoretical calculations will be discussed.

  13. Synchrotron X-ray Scattering from Self-organized Soft Nanostructures in Clays

    NASA Astrophysics Data System (ADS)

    Fossum, J. O.

    2009-04-01

    In the general context of self-organization of nanoparticles (in our case clay particles), and transitions in such structures, we study interconnected universal complex physical phenomena such as: (i) spontaneous gravitationally induced phase separation and nematic self-organization in systems of anisotropic clay nanoparticles in aqueous suspension, including studies of isotropic to nematic transitions [1,2] (ii) transitions from biaxial to uniaxial nematics by application of external magnetic field to self-organized systems of the same anisotropic (diamagnetic) clay nanoparticle systems [3,4] (iii) guided self-organization into chainlike structures of the same anisotropic clay nanoparticles in oil suspension when subjected to external electrical fields (electrorheological structures of polarized nanoparticles), and the stability of, and transitions of, such structures, when subjected to external mechanical stress [5,6] The experimental techniques used by us include synchrotron X-ray scattering, neutron scattering, rheometry. microscopy and magnetic resonance. We have demonstrated that clays may be used as good model systems for studies of universal physical phenomena and transitions in self-organized nanostructured soft and complex matter. Self-organization and related transitions in clay systems in particular, may have practical relevance for nano-patterning, properties of nanocomposites, and macroscopically anisotropic gels, among many other applications [7]. The synchrotron experiments have been performed at LNLS-Brazil, PLS- Korea, BNL-USA and ESRF-France. Acknowledgments: Collaborators, postdocs and students at NTNU-Norway, UiO-Norway, IFE-Norway, BNL-USA, LNLS-Brazil, UFPE-Brazil, UnB-Brazil, Univ. Amsterdam-Netherlands, Univ.Paris 7-France and other places. This research has been supported by the Research Council of Norway (RCN), through the NANOMAT, SUP and FRINAT Programs. References 1. J.O. Fossum, E. Gudding, D.d.M. Fonseca, Y. Meheust, E. DiMasi, T

  14. Recent progress on synchrotron-based in-situ soft X-ray spectroscopy for energy materials.

    PubMed

    Liu, Xiaosong; Yang, Wanli; Liu, Zhi

    2014-12-10

    Soft X-ray spectroscopy (SXS) techniques such as photoelectron spectroscopy, soft X-ray absorption spectroscopy and X-ray emission spectroscopy are efficient and direct tools to probe electronic structures of materials. Traditionally, these surface sensitive soft X-ray techniques that detect electrons or photons require high vacuum to operate. Many recent in situ instrument developments of these techniques have overcome this vacuum barrier. One can now study many materials and model devices under near ambient, semi-realistic, and operando conditions. Further developments of integrating the realistic sample environments with efficient and high resolution detection methods, particularly at the high brightness synchrotron light sources, are making SXS an important tool for the energy research community. In this progress report, we briefly describe the basic concept of several SXS techniques and discuss recent development of SXS instruments. We then present several recent studies, mostly in situ SXS experiments, on energy materials and devices. Using these studies, we would like to highlight that the integration of SXS and in situ environments can provide in-depth insight of material's functionality and help researchers in new energy material developments. The remaining challenges and critical research directions are discussed at the end. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Ultrafast molecular dynamics of dissociative ionization in OCS probed by soft x-ray synchrotron radiation

    NASA Astrophysics Data System (ADS)

    Ramadhan, Ali; Wales, Benji; Karimi, Reza; Gauthier, Isabelle; MacDonald, Michael; Zuin, Lucia; Sanderson, Joe

    2016-11-01

    Soft x-rays (90-173 eV) from the 3rd generation Canadian Light Source have been used in conjunction with a multi coincidence time and position sensitive detection apparatus to observe the dissociative ionization of OCS. By varying the x-ray energy we can compare dynamics from direct and Auger ionization processes, and access ionization channels which result in two or three body breakup, from 2+ to 4+ ionization states. We make several new observations for the 3+ state such as kinetic energy release limited by photon energy, and using Dalitz plots we can see evidence of timescale effects between the direct and Auger ionization process for the first time. Finally, using Dalitz plots for OCS4+ we observe for the first time that breakup involving an O2+ ion can only proceed from out of equilibrium nuclear arrangement for S(2p) Auger ionization.

  16. Soft X-Ray Microscopy Radiation Damage On Fixed Cells Investigated With Synchrotron Radiation FTIR Microscopy.

    PubMed

    Gianoncelli, A; Vaccari, L; Kourousias, G; Cassese, D; Bedolla, D E; Kenig, S; Storici, P; Lazzarino, M; Kiskinova, M

    2015-05-14

    Radiation damage of biological samples remains a limiting factor in high resolution X-ray microscopy (XRM). Several studies have attempted to evaluate the extent and the effects of radiation damage, proposing strategies to minimise or prevent it. The present work aims to assess the impact of soft X-rays on formalin fixed cells on a systematic manner. The novelty of this approach resides on investigating the radiation damage not only with XRM, as often reported in relevant literature on the topic, but by coupling it with two additional independent non-destructive microscopy methods: Atomic Force Microscopy (AFM) and FTIR Microscopy (FTIRM). Human Embryonic Kidney 293 cells were exposed to different radiation doses at 1 keV. In order to reveal possible morphological and biochemical changes, the irradiated cells were systematically analysed with AFM and FTIRM before and after. Results reveal that while cell morphology is not substantially affected, cellular biochemical profile changes significantly and progressively when increasing dose, resulting in a severe breakdown of the covalent bonding network. This information impacts most soft XRM studies on fixed cells and adds an in-depth understanding of the radiation damage for developing better prevention strategies.

  17. Soft X-ray Imaging

    SciTech Connect

    Seely, John

    1999-05-20

    The contents of this report cover the following: (1) design of the soft x-ray telescope; (2) fabrication and characterization of the soft x-ray telescope; and (3) experimental implementation at the OMEGA laser facility.

  18. Estimation of soft X-ray and EUV transition radiation power emitted from the MIRRORCLE-type tabletop synchrotron.

    PubMed

    Toyosugi, N; Yamada, H; Minkov, D; Morita, M; Yamaguchi, T; Imai, S

    2007-03-01

    The tabletop synchrotron light sources MIRRORCLE-6X and MIRRORCLE-20SX, operating at electron energies E(el) = 6 MeV and E(el) = 20 MeV, respectively, can emit powerful transition radiation (TR) in the extreme ultraviolet (EUV) and the soft X-ray regions. To clarify the applicability of these soft X-ray and EUV sources, the total TR power has been determined. A TR experiment was performed using a 385 nm-thick Al foil target in MIRRORCLE-6X. The angular distribution of the emitted power was measured using a detector assembly based on an NE102 scintillator, an optical bundle and a photomultiplier. The maximal measured total TR power for MIRRORCLE-6X is P(max) approximately equal 2.95 mW at full power operation. Introduction of an analytical expression for the lifetime of the electron beam allows calculation of the emitted TR power by a tabletop synchrotron light source. Using the above measurement result, and the theoretically determined ratio between the TR power for MIRRORCLE-6X and MIRRORCLE-20SX, the total TR power for MIRRORCLE-20SX can be obtained. The one-foil TR target thickness is optimized for the 20 MeV electron energy. P(max) approximately equal 810 mW for MIRRORCLE-20SX is obtained with a single foil of 240 nm-thick Be target. The emitted bremsstrahlung is negligible with respect to the emitted TR for optimized TR targets. From a theoretically known TR spectrum it is concluded that MIRRORCLE-20SX can emit 150 mW of photons with E > 500 eV, which makes it applicable as a source for performing X-ray lithography. The average wavelength, \\overline\\lambda = 13.6 nm, of the TR emission of MIRRORCLE-20SX, with a 200 nm Al target, could provide of the order of 1 W EUV.

  19. Correlative cryo-fluorescence and cryo-soft X-ray tomography of adherent cells at European synchrotrons.

    PubMed

    Carzaniga, Raffaella; Domart, Marie-Charlotte; Duke, Elizabeth; Collinson, Lucy M

    2014-01-01

    Cryo-soft X-ray tomography (cryo-SXT) is a synchrotron-hosted imaging technique used to analyze the ultrastructure of intact, cryo-prepared cells. Correlation of cryo-fluorescence microscopy and cryo-SXT can be used to localize fluorescent proteins to organelles preserved close to native state. Cryo-correlative light and X-ray microscopy (cryo-CLXM) is particularly useful for the study of organelles that are susceptible to chemical fixation artifacts during sample preparation for electron microscopy. In our recent work, we used cryo-CLXM to characterize GFP-LC3-positive early autophagosomes in nutrient-starved HEK293A cells (Duke et al., 2013). Cup-shaped omegasomes were found to form at "hot-spots" on the endoplasmic reticulum. Furthermore, cryo-SXT image stacks revealed the presence of large complex networks of tubulated mitochondria in the starved cells, which would be challenging to model at this scale and resolution using light or electron microscopy. In this chapter, we detail the cryo-CLXM workflow that we developed and optimized for studying adherent mammalian cells. We show examples of data collected at the three European synchrotrons that currently host cryo-SXT microscopes, and describe how raw cryo-SXT datasets are processed into tomoX stacks, modeled, and correlated with cryo-fluorescence data to identify structures of interest. © 2014 Elsevier Inc. All rights reserved.

  20. Soft X-ray synchrotron radiation spectroscopy study of molecule-based nanoparticles

    NASA Astrophysics Data System (ADS)

    Lee, Eunsook; Kim, D. H.; Kang, J.-S.; Kim, Kyung Hyun; Kim, Pil; Baik, Jaeyoon; Shin, H. J.

    2014-11-01

    The electronic structures of molecule-based nanoparticles, such as biomineralized Helicobacter pylori ferritin (Hpf), Heme, and RbCo[Fe(CN)6]H2O (RbCoFe) Prussian blue analogue, have been investigated by employing photoemission spectroscopy and soft X-ray absorption spectroscopy. Fe ions are found to be nearly trivalent in Hpf and Heme nanoparticles, which provides evidence that the amount of magnetite (Fe3O4) should be negligible in the Hpf core and that the biomineralization of Fe oxides in the high-Fe-bound-state Hpf core arises from a hematite-like formation. On the other hand, Fe ions are nearly divalent and Co ions are Co2+-Co3+ mixed-valent in RbCoFe. Therefore this finding suggests that the mechanism of the photo-induced transition in RbCoFe Prussian blue analogue is not a simple spin-state transition of Fe2+-Co3+ → Fe3+-Co2+. It is likely that Co2+ ions have the high-spin configuration while Fe2+ ions have the low-spin configuration.

  1. New insights into globoids of protein storage vacuoles in wheat aleurone using synchrotron soft X-ray microscopy

    PubMed Central

    Regvar, Marjana; Eichert, Diane; Kaulich, Burkhard; Gianoncelli, Alessandra; Pongrac, Paula; Vogel-Mikuš, Katarina; Kreft, Ivan

    2011-01-01

    Mature developed seeds are physiologically and biochemically committed to store nutrients, principally as starch, protein, oils, and minerals. The composition and distribution of elements inside the aleurone cell layer reflect their biogenesis, structural characteristics, and physiological functions. It is therefore of primary importance to understand the mechanisms underlying metal ion accumulation, distribution, storage, and bioavailability in aleurone subcellular organelles for seed fortification purposes. Synchrotron radiation soft X-ray full-field imaging mode (FFIM) and low-energy X-ray fluorescence (LEXRF) spectromicroscopy were applied to characterize major structural features and the subcellular distribution of physiologically important elements (Zn, Fe, Na, Mg, Al, Si, and P). These direct imaging methods reveal the accumulation patterns between the apoplast and symplast, and highlight the importance of globoids with phytic acid mineral salts and walls as preferential storage structures. C, N, and O chemical topographies are directly linked to the structural backbone of plant substructures. Zn, Fe, Na, Mg, Al, and P were linked to globoid structures within protein storage vacuoles with variable levels of co-localization. Si distribution was atypical, being contained in the aleurone apoplast and symplast, supporting a physiological role for Si in addition to its structural function. These results reveal that the immobilization of metals within the observed endomembrane structures presents a structural and functional barrier and affects bioavailability. The combination of high spatial and chemical X-ray microscopy techniques highlights how in situ analysis can yield new insights into the complexity of the wheat aleurone layer, whose precise biochemical composition, morphology, and structural characteristics are still not unequivocally resolved. PMID:21447756

  2. The Advanced Light Source at Lawrence Berkeley Laboratory: A high-brightness soft x-ray synchrotron-radiation facility

    SciTech Connect

    Schlachter, A.S.; Robinson, A.L.

    1990-07-01

    The Advanced Light Source, a third-generation national synchrotron-radiation facility now under construction at the Lawrence Berkeley Laboratory, is scheduled to begin serving qualified users across a broad spectrum of research areas in the spring of 1993. Based on a low-emittance electron storage ring optimized to operate at 1.5 GeV, the ALS will have 10 long straight sections available for insertion devices (undulators and wigglers) and 24 high-quality bend-magnet ports. The short pulse width (30--50 ns) will be ideal for time-resolved measurements. Undulators will generate high-brightness soft x-ray and ultraviolet (XUV) radiation from below 20 eV to above 2 keV. Wigglers and bend magnets will extend the spectrum by generating high fluxes of hard x-rays to photon energies above 10 keV. The ALS will support an extensive research program in which XUV radiation is used to study matter in all its varied gaseous, liquid, and solid forms. The high brightness will open new areas of research in the materials sciences, such as spatially resolved spectroscopy (spectromicroscopy). Biological applications will include x-ray microscopy with element-specific sensitivity in the water window of the spectrum where water is much more transparent than protein. The ALS will be an excellent research tool for atomic physics and chemistry because the high flux will allow measurements to be made with tenuous gas-phase targets. 8 refs., 7 figs., 3 tabs.

  3. Internal Soft-Tissue Anatomy of Cambrian ‘Orsten’ Arthropods as Revealed by Synchrotron X-Ray Tomographic Microscopy

    PubMed Central

    Eriksson, Mats E.; Terfelt, Fredrik; Elofsson, Rolf; Marone, Federica

    2012-01-01

    The world-famous ‘Orsten’ Konservat-Lagerstätte has yielded detailed information about Cambrian arthropods and their morphology. Internal organs or soft tissues have, however, rarely been reported, an obvious palaeobiological drawback. In this study, we employed synchrotron radiation X-ray tomographic microscopy (SRXTM) to study microscopic ‘Orsten’ arthropods from the Cambrian of Sweden: Skara minuta and two phosphatocopine species, Hesslandona sp. and Hesslandona trituberculata. This exceptionally high-resolution technique reveals internal organs or soft tissues that allow detailed comparison with equivalent structures in extant crustaceans and functional inferences to be made. The S. minuta specimen shows the digestive system and muscles that extend to the extremities. The slanting anterior portion of the head and anterior position of the mouth with a straight oesophagus suggest a primarily brushing and scraping way of feeding. The prominent head appendage muscles indicate muscle strength and good capacity for food manipulation. In the phosphatocopines the bulbous labrum is one of the most prominent morphological structures of the body. All specimens analysed reveal pairs of muscle bundles within the labrum. Based on comparisons with extant crustacean relatives, these muscles would fulfil the function of moving the labrum up and down in order to open the buccal cavity. The results of this pilot study demonstrate that there is still much to be learned about the ‘Orsten’ taxa. PMID:22870334

  4. In situ removal of carbon contamination from optics in a vacuum ultraviolet and soft X-ray undulator beamline using oxygen activated by zeroth-order synchrotron radiation.

    PubMed

    Toyoshima, Akio; Kikuchi, Takashi; Tanaka, Hirokazu; Adachi, Jun Ichi; Mase, Kazuhiko; Amemiya, Kenta

    2012-09-01

    Carbon contamination of optics is a serious issue in all soft X-ray beamlines because it decreases the quality of experimental data, such as near-edge X-ray absorption fine structure, resonant photoemission and resonant soft X-ray emission spectra in the carbon K-edge region. Here an in situ method involving the use of oxygen activated by zeroth-order synchrotron radiation was used to clean the optics in a vacuum ultraviolet and soft X-ray undulator beamline, BL-13A at the Photon Factory in Tsukuba, Japan. The carbon contamination of the optics was removed by exposing them to oxygen at a pressure of 10(-1)-10(-4) Pa for 17-20 h and simultaneously irradiating them with zeroth-order synchrotron radiation. After the cleaning, the decrease in the photon intensity in the carbon K-edge region reduced to 2-5%. The base pressure of the beamline recovered to 10(-7)-10(-8) Pa in one day without baking. The beamline can be used without additional commissioning.

  5. Nanoscale characterization of local structures and defects in photonic crystals using synchrotron-based transmission soft X-ray microscopy

    PubMed Central

    Nho, Hyun Woo; Kalegowda, Yogesh; Shin, Hyun-Joon; Yoon, Tae Hyun

    2016-01-01

    For the structural characterization of the polystyrene (PS)-based photonic crystals (PCs), fast and direct imaging capabilities of full field transmission X-ray microscopy (TXM) were demonstrated at soft X-ray energy. PS-based PCs were prepared on an O2-plasma treated Si3N4 window and their local structures and defects were investigated using this label-free TXM technique with an image acquisition speed of ~10 sec/frame and marginal radiation damage. Micro-domains of face-centered cubic (FCC (111)) and hexagonal close-packed (HCP (0001)) structures were dominantly found in PS-based PCs, while point and line defects, FCC (100), and 12-fold symmetry structures were also identified as minor components. Additionally, in situ observation capability for hydrated samples and 3D tomographic reconstruction of TXM images were also demonstrated. This soft X-ray full field TXM technique with faster image acquisition speed, in situ observation, and 3D tomography capability can be complementally used with the other X-ray microscopic techniques (i.e., scanning transmission X-ray microscopy, STXM) as well as conventional characterization methods (e.g., electron microscopic and optical/fluorescence microscopic techniques) for clearer structure identification of self-assembled PCs and better understanding of the relationship between their structures and resultant optical properties. PMID:27087141

  6. Nanoscale characterization of local structures and defects in photonic crystals using synchrotron-based transmission soft X-ray microscopy

    NASA Astrophysics Data System (ADS)

    Nho, Hyun Woo; Kalegowda, Yogesh; Shin, Hyun-Joon; Yoon, Tae Hyun

    2016-04-01

    For the structural characterization of the polystyrene (PS)-based photonic crystals (PCs), fast and direct imaging capabilities of full field transmission X-ray microscopy (TXM) were demonstrated at soft X-ray energy. PS-based PCs were prepared on an O2-plasma treated Si3N4 window and their local structures and defects were investigated using this label-free TXM technique with an image acquisition speed of ~10 sec/frame and marginal radiation damage. Micro-domains of face-centered cubic (FCC (111)) and hexagonal close-packed (HCP (0001)) structures were dominantly found in PS-based PCs, while point and line defects, FCC (100), and 12-fold symmetry structures were also identified as minor components. Additionally, in situ observation capability for hydrated samples and 3D tomographic reconstruction of TXM images were also demonstrated. This soft X-ray full field TXM technique with faster image acquisition speed, in situ observation, and 3D tomography capability can be complementally used with the other X-ray microscopic techniques (i.e., scanning transmission X-ray microscopy, STXM) as well as conventional characterization methods (e.g., electron microscopic and optical/fluorescence microscopic techniques) for clearer structure identification of self-assembled PCs and better understanding of the relationship between their structures and resultant optical properties.

  7. ALFT's Soft X-Ray Source Development

    NASA Astrophysics Data System (ADS)

    Panarella, Emilio

    2002-11-01

    ALFT (www.alft.com) was funded by the Federal and Provincial governments of Canada in 1987 to pursue the objective of making soft X-ray sources for microlithography.For 15 years ALFT has successfully pursued this objective. Recently, the company has found that its sources can complement the synchrotron as provider of soft X-rays for applications that range from biotechnology to nanotechnology.A beam from the Canadian Synchrotron (CLS) will deliver 10^13 photons/sec in a collimated output, whereas the weakest of ALFT's sources delivers an average of 10^15 photons/sec, two orders of magnitude higher than the synchrotron, albeit in the 4 pi direction. The most powerful of ALFT's sources delivers pulses carrying an average of 10^16 photons/sec, with peak flux of 10^24 photons/sec, again in the 4 pi.The proprietary technology of ALFT rests not only on the electron bombardment concept of X-ray production but also, by using a special plasma (the Vacuum Spark), on the pinch phenomenon, thus obtaining better efficiency than conventional sources. By discharging a simple condenser in a very low inductance circuit, a metallic plasma is generated in a vacuum vessel between two electrodes, where plasma pinch and micropinch phenomena raise the plasma temperature and density to values that lead to large soft X-ray production.The talk will present an overview of the VSX soft X-ray source development, examining first the physics of the vacuum spark, then the extendibility to higher power outputs, and then to the engineering issues that have been solved leading to the first product, the VSX 400, a machine that delivers 400 mW of soft X-rays, and to the VSX Z10, a prototype machine that delivers 10 W of X-rays.The recent visits to the CLS and follow-up discussions that are leading towards the placement of one VSX 400 machine in Saskatoon will also reported.

  8. Study of multilayer structures as soft x-ray mirrors

    NASA Astrophysics Data System (ADS)

    Kim, D.; Lee, H. W.; Cha, D.; Lee, J. J.; Je, J. H.

    1995-05-01

    Molybdenum-silicon multilayer as soft x-ray mirrors have been fabricated using a magnetron sputtering system. Their structures have been characterized by x-ray diffraction (XRD) and computer simulation. Reflectivities at normal incidence have been measured by using monochromatized synchrotron radiation in the 18-24 nm region. A normal incidence reflectivity as high as 40% at 20.8 nm was achieved. Multilayer structural parameters optimized for various soft x-ray laser wavelengths are also given.

  9. The advanced light source at Lawrence Berkeley Laboratory—A high-brightness soft x-ray synchrotron-radiation facility

    NASA Astrophysics Data System (ADS)

    Schlachter, Alfred S.; Robinson, Arthur L.

    1990-12-01

    The Advanced Light Source, a third-generation national synchrotron-radiation facility now under construction at the Lawrence Berkeley Laboratory, is scheduled to begin serving qualified users across a broad spectrum of research areas in the spring of 1993. Based on a low-emittance electron storage ring optimized to operate at 1.5 GeV, the ALS will have 10 long straight sections available for insertion devices (undulators and wigglers) and 24 high-quality bend-magnet ports. The short pulse width (30-50 ns) will be ideal for time-resolved measurements. Undulators will generate high-brightness soft x-ray and ultraviolet (XUV) radiation from below 10 eV to above 2 keV. Wigglers and bend magnets will extend the spectrum by generating high fluxes of hard x-rays to photon energies above 10 keV. The ALS will support an extensive research program in which XUV radiation is used to study matter in all its varied gaseous, liquid, and solid forms. The high brightness will open new areas of research in the materials sciences, such as spatially resolved spectroscopy (spectromicroscopy). Biological applications will include x-ray microscopy with element-specific sensitivity in the water window of the spectrum where water is much more transparent than protein. The ALS will be an excellent research tool for atomic physics and chemistry because the high flux will allow measurements to be made with tenuous gas-phase targets.

  10. Using in-situ synchrotron x-ray diffraction to investigate phase transformation and lattice relaxation of a three-way piezo-phototronic soft material

    NASA Astrophysics Data System (ADS)

    Ko, Wen-Ching; Hsu, Yu-Hsiang; Weng, Shih-Chang; Chang, Chung-Kai; Lee, Ming-Tao; Chuang, Wei-Tsung; Thong, Hao-Cheng; Ali, Muhammad; Huang, E.-Wen

    2017-07-01

    A poly(vinylidene fluoride-co-trifluoro-ethylene) piezoelectric polymer is blended with nano particles of titanium oxide phthalocyanine to bridge photoconductive and piezoelectric effects. In this study, a system is examined by in situ synchrotron x-ray to test a three-way piezo-phototronic soft-material design. The sample is heated for in situ phase transformation characterization. The semi-crystalline poly (vinylidene fluoride-co-trifluoro-ethylene) polymer gradually transforms to an amorphous structure. A complementary piezoelectric experiment before and after the heating experiment shows that the piezoelectric performance is proportional to the phase ratio. Secondly, the system is examined to test its phototronic effect. Piezoelectric responses are measured by controlling the light illumination. The positive and negative controls of light illumination which validate this newly-designed system can be modulated by a three-way piezo-phototronic effect. In-situ synchrotron x-ray diffraction experiments are employed to measure the microstructure evolution as a function of applied voltage up to 800 V. We then turned off both the light and the applied voltage to examine the kinetic behavior of the system. There is orientation-dependent anisotropic relaxation. We compared the lattice-strain evolutions. Piezo-phototronic creep is found in the (110), but not the (310) planes.

  11. Final Scientific/Technical Report: Electronics for Large Superconducting Tunnel Junction Detector Arrays for Synchrotron Soft X-ray Research

    SciTech Connect

    Warburton, William K

    2009-03-06

    Superconducting tunnel junction (STJ) detectors offer a an approach to detecting soft x-rays with energy resolutions 4-5 times better and at rates 10 faster than traditions semiconductor detectors. To make such detectors feasible, however, then need to be deployed in large arrays of order 1000 detectors, which in turn implies that their processing electronics must be compact, fully computer controlled, and low cost per channel while still delivering ultra-low noise performance so as to not degrade the STJ's performance. We report on our progress in designing a compact, low cost preamplifier intended for this application. In particular, we were able to produce a prototype preamplifier of 2 sq-cm area and a parts cost of less than $30 that matched the energy resolution of the best conventional system to date and demonstrated its ability to acquire an STJ I-V curve under computer control, the critical step for determining and setting the detectors' operating points under software control.

  12. X-ray imaging detectors for synchrotron and XFEL sources

    PubMed Central

    Hatsui, Takaki; Graafsma, Heinz

    2015-01-01

    Current trends for X-ray 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 X-ray 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 X-ray photons. The link between technology development and detector performance is described briefly in the context of potential future capabilities for X-ray imaging detectors. PMID:25995846

  13. X-ray imaging detectors for synchrotron and XFEL sources.

    PubMed

    Hatsui, Takaki; Graafsma, Heinz

    2015-05-01

    Current trends for X-ray 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 X-ray 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 X-ray photons. The link between technology development and detector performance is described briefly in the context of potential future capabilities for X-ray imaging detectors.

  14. Soft x-ray interferometry

    SciTech Connect

    Not Available

    1993-09-01

    The purpose of the soft x-ray interferometry workshop held at Lawrence Berkeley Laboratory was to discuss with the scientific community the proposed technical design of the soft x-ray Fourier-transform spectrometer being developed at the ALS. Different design strategies for the instrument`s components were discussed, as well as detection methods, signal processing issues, and how to meet the manufacturing tolerances that are necessary for the instrument to achieve the desired levels of performance. Workshop participants were encouraged to report on their experiences in the field of Fourier transform spectroscopy. The ALS is developing a Fourier transform spectrometer that is intended to operate up to 100 eV. The motivation is solely improved resolution and not the throughput (Jaquinot) or multiplex (Fellgett) advantage, neither of which apply for the sources and detectors used in this spectral range. The proposed implementation of this is via a Mach-Zehnder geometry that has been (1) distorted from a square to a rhombus to get grazing incidence of a suitable angle for 100 eV and (2) provided with a mirror-motion system to make the path difference between the interfering beams tunable. The experiment consists of measuring the emergent light intensity (I(x)) as a function of the path difference (x). The resolving power of the system is limited by the amount of path difference obtainable that is 1 cm (one million half-waves at 200{angstrom} wavelength) in the design thus allowing a resolving power of one million. The free spectral range of the system is limited by the closeness with which the function I(x) is sampled. It is proposed to illuminate a helium absorption cell with roughly 1%-band-width light from a monochromator thus allowing one hundred aliases without spectral overlap even for sampling of I(x) at one hundredth of the Nyquist frequency.

  15. Soft X-ray synchrotron radiation spectroscopy study of rare-earth chalcogenide charge-density wave compounds

    NASA Astrophysics Data System (ADS)

    Lee, Eunsook; Kim, Hyun Woo; Seong, Seungho; Denlinger, J. D.; Kwon, Y. S.; Kang, J.-S.

    2017-02-01

    The electronic structures of the layered rare-earth chalcogenide compounds of CeTe2, PrTe2, and PrTe3, which have the charge-density wave (CDW) transition and possibly the chiral transition, have been investigated by employing soft X-ray absorption spectroscopy (XAS) and angle-resolved photoemission spectroscopy (ARPES). R 3 d XAS measurements show that the valence states of Ce and Pr ions are nearly trivalent in all the compounds. Similar band dispersions are observed in their measured ARPES data, but with the band positions in PrTe3 being shifted up in energy compared to those in CeTe2 and PrTe2. These findings suggest that their Te 5 p band structures are determined mainly by the 2D interactions in the Te(2)/Te(3) sheets, but with a larger number of holes in the Te 5 p bands in PrTe3 than in CeTe2 and PrTe2. The measured constant energy maps of CeTe2, PrTe2, and PrTe3 for high binding energies are similar to one another, reflecting the Te 5 p band structures of the Te(2)/Te(3) square nets. In contrast, the Fermi surfaces (FSs) of CeTe2 and PrTe3 exhibit extra features, different from the FS of the ideal Te(2)/Te(3) square nets, which arise from the CDW-induced FS reconstruction in the Te(2)/Te(3) sheets.

  16. Multilayers for EUV, soft x-ray and x-ray optics

    NASA Astrophysics Data System (ADS)

    Wang, Zhanshan; Huang, Qiushi; Zhang, Zhong

    2016-02-01

    Driven by the requirements in synchrotron radiation applications, astronomical observation, and dense plasma diagnostics, the EUV, soft X-rays and X-rays multilayer optics have been tremendously developed. Based on the LAMP project for soft X-ray polarimetry, Co/C and Cr/C multilayers have been fabricated and characterized. Both Co/C and Cr/C multilayers reveal good optical performance working at 250 eV. Pd/Y multilayers have been successfully fabricated using reactive sputtering with nitrogen working at around 9.4 nm. EUV normal incidence Schwarzschild and soft X-ray grazing incidence KB microscopes were developed for ICF plasma diagnostics. This paper covers the outline of the multilayer optics and the current status in our lab.

  17. Applications of soft x-ray lasers

    SciTech Connect

    Skinner, C.H.

    1993-08-01

    The high brightness and short pulse duration of soft x-ray lasers provide unique advantages for novel applications. Imaging of biological specimens using x-ray lasers has been demonstrated by several groups. Other applications to fields such as chemistry, material science, plasma diagnostics, and lithography are beginning to emerge. We review the current status of soft x-ray lasers from the perspective of applications, and present an overview of the applications currently being developed.

  18. Soft-x-ray spectroscopy study of nanoscale materials

    SciTech Connect

    Guo, J.-H.

    2005-07-30

    The ability to control the particle size and morphology of nanoparticles is of crucial importance nowadays both from a fundamental and industrial point of view considering the tremendous amount of high-tech applications. Controlling the crystallographic structure and the arrangement of atoms along the surface of nanostructured material will determine most of its physical properties. In general, electronic structure ultimately determines the properties of matter. Soft X-ray spectroscopy has some basic features that are important to consider. X-ray is originating from an electronic transition between a localized core state and a valence state. As a core state is involved, elemental selectivity is obtained because the core levels of different elements are well separated in energy, meaning that the involvement of the inner level makes this probe localized to one specific atomic site around which the electronic structure is reflected as a partial density-of-states contribution. The participation of valence electrons gives the method chemical state sensitivity and further, the dipole nature of the transitions gives particular symmetry information. The new generation synchrotron radiation sources producing intensive tunable monochromatized soft X-ray beams have opened up new possibilities for soft X-ray spectroscopy. The introduction of selectively excited soft X-ray emission has opened a new field of study by disclosing many new possibilities of soft X-ray resonant inelastic scattering. In this paper, some recent findings regarding soft X-ray absorption and emission studies of various nanostructured systems are presented.

  19. Inactivation action spectra of Bacillus subtilis spores with monochromatic soft X rays (0.1-0.6 nm) of synchrotron radiation.

    PubMed

    Munakata, N; Hieda, K; Usami, N; Yokoya, A; Kobayashi, K

    1992-07-01

    Five types of Bacillus subtilis spores differing in DNA repair and recombinational capacities were exposed in vacuum to monochromatic soft X rays from synchrotron radiation. The inactivation rate constants were obtained from exposure-survival curves upon irradiations at 12 wavelengths in the range of 0.1000 nm (12.40 keV) to 0.6000 nm (2.066 keV). Spores of two repair-deficient strains, UVS (uvrA ssp) and UVP (uvrA ssp polA), exhibited almost equal sensitivities to those of wild-type UVR+, while those of two recombination-deficient strains, RCE (recE) and RCF (recF), exhibited higher sensitivities in the whole wavelength range. This suggested that the repair of DNA damage produced by soft X rays was dependent on the recombinational capabilities. Inactivation action spectra based on photon fluence showed that the effectiveness of the radiation increased as the wavelengths became longer. Abrupt changes in the effectiveness occurred around the wavelengths corresponding to the absorption edges of K-shell electrons of phosphorus and calcium. In both cases, the sensitivity was the highest at the wavelengths of the resonance absorption peak, the next highest at those of the higher energy, and the lowest at the lower energy. Mass energy absorption coefficients of spores were obtained from the transmission of a flake made of spores. They were used to derive inactivation action spectra based on absorbed doses. In these spectra, basal levels of the sensitivity seemed constant, and enhancements of the sensitivity were observed consistent with the absorption by calcium and phosphorus. Thus calcium and phosphorus atoms were the predominant targets for the absorption events leading to the inactivation of spores in the wavelength range examined.

  20. Synchrotron soft X-ray imaging and fluorescence microscopy reveal novel features of asbestos body morphology and composition in human lung tissues

    PubMed Central

    2011-01-01

    Background Occupational or environmental exposure to asbestos fibres is associated with pleural and parenchymal lung diseases. A histopathologic hallmark of exposure to asbestos is the presence in lung parenchyma of the so-called asbestos bodies. They are the final product of biomineralization processes resulting in deposition of endogenous iron and organic matter (mainly proteins) around the inhaled asbestos fibres. For shedding light on the formation mechanisms of asbestos bodies it is of fundamental importance to characterize at the same length scales not only their structural morphology and chemical composition but also to correlate them to the possible alterations in the local composition of the surrounding tissues. Here we report the first correlative morphological and chemical characterization of untreated paraffinated histological lung tissue samples with asbestos bodies by means of soft X-ray imaging and X-Ray Fluorescence (XRF) microscopy, which reveals new features in the elemental lateral distribution. Results The X-ray absorption and phase contrast images and the simultaneously monitored XRF maps of tissue samples have revealed the location, distribution and elemental composition of asbestos bodies and associated nanometric structures. The observed specific morphology and differences in the local Si, Fe, O and Mg content provide distinct fingerprints characteristic for the core asbestos fibre and the ferruginous body. The highest Si content is found in the asbestos fibre, while the shell and ferruginous bodies are characterized by strongly increased content of Mg, Fe and O compared to the adjacent tissue. The XRF and SEM-EDX analyses of the extracted asbestos bodies confirmed an enhanced Mg deposition in the organic asbestos coating. Conclusions The present report demonstrates the potential of the advanced synchrotron-based X-ray imaging and microspectroscopy techniques for studying the response of the lung tissue to the presence of asbestos fibres

  1. Soft X-Ray and Vacuum Ultraviolet Based Spectroscopy of the Actinides

    SciTech Connect

    Tobin, J G

    2011-03-17

    The subjects of discussion included: VUV photoelectron spectroscopy, X-ray photoelectron spectroscopy, Synchrotron-radiation-based photoelectron spectroscopy, Soft x-ray absorption spectroscopy, Soft x-ray emission spectroscopy, Inverse photoelectron spectroscopy, Bremstrahlung Isochromat Spectroscopy, Low energy IPES, Resonant inverse photoelectron spectroscopy.

  2. HERMES: a soft X-ray beamline dedicated to X-ray microscopy.

    PubMed

    Belkhou, Rachid; Stanescu, Stefan; Swaraj, Sufal; Besson, Adrien; Ledoux, Milena; Hajlaoui, Mahdi; Dalle, Didier

    2015-07-01

    The HERMES beamline (High Efficiency and Resolution beamline dedicated to X-ray Microscopy and Electron Spectroscopy), built at Synchrotron SOLEIL (Saint-Auban, France), is dedicated to soft X-ray microscopy. The beamline combines two complementary microscopy methods: XPEEM (X-ray Photo Emitted Electron Microscopy) and STXM (Scanning Transmission X-ray Microscopy) with an aim to reach spatial resolution below 20 nm and to fully exploit the local spectroscopic capabilities of the two microscopes. The availability of the two methods within the same beamline enables the users to select the appropriate approach to study their specific case in terms of sample environment, spectroscopy methods, probing depth etc. In this paper a general description of the beamline and its design are presented. The performance and specifications of the beamline will be reviewed in detail. Moreover, the article is aiming to demonstrate how the beamline performances have been specifically optimized to fulfill the specific requirements of a soft X-ray microscopy beamline in terms of flux, resolution, beam size etc. Special attention has been dedicated to overcome some limiting and hindering problems that are usually encountered on soft X-ray beamlines such as carbon contamination, thermal stability and spectral purity.

  3. The PERCIVAL soft X-ray imager

    NASA Astrophysics Data System (ADS)

    Wunderer, C. B.; Marras, A.; Bayer, M.; Correa, J.; Göttlicher, P.; Lange, S.; Shevyakov, I.; Smoljanin, S.; Tennert, M.; Viti, M.; Xia, Q.; Zimmer, M.; Das, D.; Guerrini, N.; Marsh, B.; Sedgwick, I.; Turchetta, R.; Cautero, G.; Gianoncelli, A.; Giuressi, D.; Menk, R.; Stebel, L.; Yousef, H.; Marchal, J.; Rees, N.; Tartoni, N.; Graafsma, H.

    2015-02-01

    With the increased brilliance of state-of-the-art Synchrotron radiation sources and the advent of Free Electron Lasers enabling revolutionary science on atomic length and time scales with EUV to X-ray photons comes an urgent need for suitable photon imaging detectors. Requirements include high frame rates, very large dynamic range, single-photon counting capability with low probability of false positives, and (multi)-megapixels. PERCIVAL (``Pixelated Energy Resolving CMOS Imager, Versatile And Large'') is currently being developed by a collaboration of DESY, RAL, Elettra, DLS and Pohang to address this need for the soft X-ray regime. PERCIVAL is a monolithic active pixel sensor (MAPS), i.e. based on CMOS technology. It will be back-thinned to access its primary energy range of 250 eV to 1 keV with target efficiencies above 90%. According to its preliminary specifications, the roughly 10 × 10 cm2, 3.5k × 3.7k monolithic ``PERCIVAL13M'' sensor will operate at frame rates up to 120 Hz (commensurate with most FELs) and use multiple gains within its 27 μm pixels to measure 1 to ~ 105 (500 eV) simultaneously-arriving photons. A smaller ``PERCIVAL2M'' with ~ 1.4k × 1.5k pixels is also planned. Currently, small-scale back-illuminated prototype systems (160 × 210 pixels of 25 μm pitch) are undergoing detailed testing with X-rays and optical photons. In March 2014, a prototype sensor was tested at 350 eV-2 keV at Elettra's TwinMic beamline. The data recorded include diffraction patterns at 350 eV and 400 eV, knife edge and sub-pixel pinhole illuminations, and comparisons of different pixel types. Another prototype chip will be submitted in fall 2014, first larger sensors could be in hand in late 2015.

  4. Challenges for Synchrotron X-Ray Optics

    NASA Astrophysics Data System (ADS)

    Freund, Andreas K.

    2002-12-01

    It is the task of x-ray 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 x-ray 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 x-ray 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 future x-ray 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

  5. Performance of the undulator based ultraviolet and soft x-ray beamline for catalysis and surface science at National Synchrotron Radiation Laboratory

    NASA Astrophysics Data System (ADS)

    Du, Liangliang; Du, Xuewei; Wei, Shen; Li, Chaoyang; Pan, Congyuan; Ju, Huanxin; Wang, Qiuping; Zhu, Junfa

    2016-12-01

    The undulator based ultraviolet and soft x-ray beamline BL11U for catalysis and surface science at National Synchrotron Radiation Laboratory (NSRL) has been under opteration for months and the present performance is described. This beamline utilizes radiation from an in-vacuum undulator, which has 30 magnetic periods with the period length of 40 mm. A varied-line-spacing plane grating monochromator is employed tto cover the photon energy region of 20-600 eV by two gratings with nominal groove densities of 400 llmm and 1200 l/mm respectively. The energy resolution power E/ΔE is measured with a gas ionization chamber and the photon flux is measured by a photodiode. Results show that the resolution power is better than 10,000 at a photon energy of 29.2 eV. And the flux is higher than 1×1010 phs/s under 300 mA ring beam current for most of the covered photon energy.

  6. Synchrotron x-ray fluorescence and extended x-ray absorption fine structure analysis

    SciTech Connect

    Chen, J.R.; Gordon, B.M.; Hanson, A.L.; Jones, K.W.; Kraner, H.W.; Chao, E.C.T.; Minkin, J.A.

    1984-01-01

    The advent of dedicated synchrotron radiation sources has led to a significant increase in activity in many areas of science dealing with the interaction of x-rays with matter. Synchrotron radiation provides intense, linearly polarized, naturally collimated, continuously tunable photon beams, which are used to determine not only the elemental composition of a complex, polyatomic, dilute material but also the chemical form of the elements with improved accuracy. Examples of the application of synchrotron radiation include experiments in synchrotron x-ray fluorescence (SXRF) analysis and extended x-ray absorption fine structure (EXAFS) analysis. New synchrotron radiation x-ray microprobes for elemental analysis in the parts per billion range are under construction at several laboratories. 76 references, 24 figures.

  7. Absolute calibration of a soft X-ray spectrograph for X-ray laser research using white beam.

    PubMed

    Fujikawa, C; Kawachi, T; Ando, K; Yamaguchi, N; Hara, T

    1998-05-01

    Absolute calibration of a soft X-ray spectrograph has been performed using a white beam of synchrotron radiation. The calibrated spectrograph was a flat-field grazing-incidence spectrograph with an X-ray CCD detector for X-ray laser research. Absolute sensitivity of the spectrograph system can be obtained from transmitted spectra using filters made of several different materials, each providing an absorption-edge wavelength standard. The absolute sensitivity determined in this work shows nearly the same behaviour with wavelength as that in another calibration experiment using a laser-produced plasma as an X-ray source.

  8. The superconducting high-resolution soft X-ray spectrometer at the advanced biological and environmental X-ray facility

    NASA Astrophysics Data System (ADS)

    Friedrich, S.; Drury, O. B.; George, S. J.; Cramer, S. P.

    2007-11-01

    We have built a 36-pixel superconducting tunnel junction X-ray spectrometer for chemical analysis of dilute samples in the soft X-ray band. It offers an energy resolution of ˜10-20 eV FWHM below 1 keV, a solid angle coverage of ˜10 -3, and can be operated at total rates of up to ˜10 6 counts/s. Here, we describe the spectrometer performance in speciation measurements by fluorescence-detected X-ray absorption spectroscopy at the Advanced Biological and Environmental X-ray facility at the ALS synchrotron.

  9. Larch: X-ray Analysis for Synchrotron Applications using Python

    NASA Astrophysics Data System (ADS)

    Newville, Matthew

    2017-03-01

    Larch is an open-source library and toolkit written in Python for processing and analyzing X-ray spectroscopic data. The primary emphasis is on X-ray spectroscopic and scattering data collected at modern synchrotron sources. Larch provides a wide selection of general-purpose processing, analysis, and visualization tools for processing X-ray data; its related target application areas include X-ray absorption fine structure (XAFS), micro-X-ray fluorescence (XRF) maps, quantitative X-ray fluorescence, X-ray absorption near edge spectroscopy (XANES), and X-ray standing waves and surface scattering. Larch provides a complete set of XAFS Analysis tools and has support for visualizing and analyzing XRF maps and spectra, and additional tools for X-ray spectral analysis, data handling, and general-purpose data modeling.

  10. Soft x-ray tomography on TFTR

    SciTech Connect

    Kuo-Petravic, G.

    1988-12-01

    The tomographic method used for deriving soft x-ray local emissivities on TFTR, using one horizontal array of 60 soft x-ray detectors, is described. This method, which is based on inversion of Fourier components and subsequent reconstruction, has been applied to the study of a sawtooth crash. A flattening in the soft x-ray profile, which we interpret as an m = 1 island, is clearly visible during the precursor phase and its location and width correlate well with those from electron temperature profiles reconstructed from electron cyclotron emission measurement. The limitations of the Fourier method, due notably to the aperiodic nature of the signals in the fast crash phase and the difficulty of obtaining accurately the higher Fourier harmonics, are discussed. 9 refs., 13 figs.

  11. In situ soft X-ray absorption spectroscopy of flames

    NASA Astrophysics Data System (ADS)

    Frank, Jonathan H.; Shavorskiy, Andrey; Bluhm, Hendrik; Coriton, Bruno; Huang, Erxiong; Osborn, David L.

    2014-10-01

    The feasibility of in situ soft X-ray absorption spectroscopy for imaging carbonaceous species in hydrocarbon flames is demonstrated using synchrotron radiation. Soft X-rays are absorbed by core level electrons in all carbon atoms regardless of their molecular structure. Core electron spectroscopy affords distinct advantages over valence spectroscopy, which forms the basis of traditional laser diagnostic techniques for combustion. In core level spectroscopy, the transition linewidths are predominantly determined by the instrument response function and the decay time of the core-hole, which is on the order of a femtosecond. As a result, soft X-ray absorption measurements can be performed in flames with negligible Doppler and collisional broadening. Core level spectroscopy has the further advantage of measuring all carbonaceous species regardless of molecular structure in the far-edge region, whereas near-edge features are molecule specific. Interferences from non-carbon flame species are unstructured and can be subtracted. In the present study, absorption measurements in the carbon K-edge region are demonstrated in low-pressure ( P total = 20-30 Torr) methane jet flames. Two-dimensional imaging of the major carbonaceous species, CH4, CO2, and CO, is accomplished by tuning the synchrotron radiation to the respective carbon K-edge, near-edge X-ray absorption fine structure (NEXAFS) transitions and scanning the burner.

  12. Laboratory cryo soft X-ray microscopy.

    PubMed

    Hertz, H M; von Hofsten, O; Bertilson, M; Vogt, U; Holmberg, A; Reinspach, J; Martz, D; Selin, M; Christakou, A E; Jerlström-Hultqvist, J; Svärd, S

    2012-02-01

    Lens-based water-window X-ray microscopy allows two- and three-dimensional (2D and 3D) imaging of intact unstained cells in their near-native state with unprecedented contrast and resolution. Cryofixation is essential to avoid radiation damage to the sample. Present cryo X-ray microscopes rely on synchrotron radiation sources, thereby limiting the accessibility for a wider community of biologists. In the present paper we demonstrate water-window cryo X-ray microscopy with a laboratory-source-based arrangement. The microscope relies on a λ=2.48-nm liquid-jet high-brightness laser-plasma source, normal-incidence multilayer condenser optics, 30-nm zone-plate optics, and a cryo sample chamber. We demonstrate 2D imaging of test patterns, and intact unstained yeast, protozoan parasites and mammalian cells. Overview 3D information is obtained by stereo imaging while complete 3D microscopy is provided by full tomographic reconstruction. The laboratory microscope image quality approaches that of the synchrotron microscopes, but with longer exposure times. The experimental image quality is analyzed from a numerical wave-propagation model of the imaging system and a path to reach synchrotron-like exposure times in laboratory microscopy is outlined. Copyright © 2011 Elsevier Inc. All rights reserved.

  13. Resonant Soft X-ray Scattering for Soft Materials

    NASA Astrophysics Data System (ADS)

    Wang, Cheng; Young, Athony; Hexemer, Alexander; Padmore, Howard

    2015-03-01

    Over the past a few years, we have developed Resonant Soft X-ray Scattering (RSoXS) and constructed the first dedicated resonant soft x-ray scattering beamline at the Advanced Light Source, LBNL. RSoXS combines soft x-ray spectroscopy with x-ray scattering thus offers statistical information for 3D chemical morphology over a large length scale range from nanometers to micrometers. Its unique chemical sensitivity, large accessible size scale, molecular bond orientation sensitivity with polarized x-rays and high coherence have shown great potential for chemical/morphological structure characterization for many classes of materials. Some recent development of in-situ soft x-ray scattering with in-vacuum sample environment will be discussed. In order to study sciences in naturally occurring conditions, we need to overcome the sample limitations set by the low penetration depth of soft x-rays and requirement of high vacuum. Adapting to the evolving environmental cell designs utilized increasingly in the Electron Microscopy community, customized designed liquid/gas environmental cells will enable soft x-ray scattering experiments on biological, electro-chemical, self-assembly, and hierarchical functional systems in both static and dynamic fashion. Recent RSoXS results on organic electronics, block copolymer thin films, and membrane structure will be presented.

  14. Fan-beam monochromatic x-ray CT using fluorescent x rays excited by synchrotron radiation

    NASA Astrophysics Data System (ADS)

    Toyofuku, Fukai; Tokumori, Kenji; Kanda, Shigenobu; Higashida, Yoshiharu; Ohki, Masafumi; Cho, Tetsuji; Nishimura, Katsuyuki; Hyodo, Kazuyuki; Ando, Masami; Uyama, Chikao

    1999-10-01

    Monochromatic x-ray CT has several advantages over conventional CT, which utilizes bremsstrahlung white x-rays from an x-ray tube. Although various types of monochromatic x-ray CT systems using synchrotron radiation have been developed using a parallel x-ray beam for imaging of small samples with a high spatial resolution, imaging of large objects such as the human body have not been developed yet. We have developed a fan-beam monochromatic x-ray CT using fluorescent x-rays generated by irradiating metal targets by synchrotron radiation. A CdTe linear array detector of 512 mm sensitive width was used in the photon counting mode. We made phantom experiments using fluorescent x-rays ranging from 32 to 75 keV. Monochromatic x-ray CT images of a cylindrical lucite phantom filled with several contrast media have been obtained. Measured CT numbers are compared with linear attenuation coefficients, and they showed a good linearity over a wide range of contrast media concentrations.

  15. European XFEL: Soft X-Ray instrumentation

    SciTech Connect

    Molodtsov, S. L.

    2011-12-15

    The currently constructed European X-Ray Free Electron Laser (XFEL) will generate new knowledge in almost all the technical and scientific disciplines that are shaping our daily life-including nanotechnology, medicine, pharmaceutics, chemistry, materials science, power engineering and electronics. On 8 January 2009, civil engineering work (tunnels, shafts, halls) has been started at all three construction sites. In this presentation status and parameters of the European XFEL facility and instrumentation as well as planned research applications particularly in the range of soft X-rays are reviewed.

  16. Reflection soft X-ray microscope and method

    DOEpatents

    Suckewer, S.; Skinner, C.H.; Rosser, R.

    1993-01-05

    A reflection soft X-ray microscope is provided by generating soft X-ray beams, condensing the X-ray beams to strike a surface of an object at a predetermined angle, and focusing the X-ray beams reflected from the surface onto a detector, for recording an image of the surface or near surface features of the object under observation.

  17. Reflection soft X-ray microscope and method

    DOEpatents

    Suckewer, Szymon; Skinner, Charles H.; Rosser, Roy

    1993-01-01

    A reflection soft X-ray microscope is provided by generating soft X-ray beams, condensing the X-ray beams to strike a surface of an object at a predetermined angle, and focusing the X-ray beams reflected from the surface onto a detector, for recording an image of the surface or near surface features of the object under observation.

  18. Soft x-ray laser microscope

    SciTech Connect

    Suckewer, P.I.

    1990-10-01

    The program consisted of two phases (Phase I and Phase II). The goal of the Phase I (first year program) was to design and construct the Soft X-ray Laser Contact Microscope. Such microscope was constructed and adapted to PPL's 18.2nm soft X-ray Laser (SXL), which in turn was modified and prepared for microscopy experiments. Investigation of the photoresist response to 18.2nm laser radiation and transmissivity of 0.1m thick silicion-nitride (Si[sub 3]N[sub 4]) windows were important initial works. The goal of the first year of Phase II was to construct X-ray contact microscope in combination with existing optical phase microscope, already used by biologists. In the second year of Phase II study of dehydrated Horeseshoe Crab and Hela cancer cells were performed with COXRALM. Also during Phase II, the Imaging X-Ray Laser Microscope (IXRALM) was designed and constructed. This paper describes the development of each of the microscopes and their application for research.

  19. Non-periodic multilayer coatings in EUV, soft x-ray and x-ray range

    NASA Astrophysics Data System (ADS)

    Wang, Zhanshan

    2008-09-01

    Non-periodic multilayer coatings offer engineer great flexibility to achieve tailored spectral performance in EUV, soft X-ray and X-ray region. We have developed a variety of non-periodic multilayer mirrors for use as optical key components for polarization-sensitive studies, Kirkpatrick-Baez microscope, Earth's magnetosphere observation and reflection of sub-femtosecond pulses. To find optimal distribution of layer thicknesses for a given spectral response, several numerical algorithms, such as simplex, simulated annealing, genetic and Levenberg Marquardt, have been explored to solve the reverse optimization problems. The designed non-periodic multilayers were prepared by use of a direct current magnetron sputtering system and characterized by grazing incidence x-ray reflectometry analysis. The synchrotron measurements of these samples were performed at the National Synchrotron Radiation Laboratory, China and at the beamline UE56/1-PGM-1 at BESSY II Berlin, Germany. This paper covers our recent results of design and fabrication of non-periodic multilayer coatings. And the mirror performance and limitations were also briefly reviewed.

  20. Synchrotron-Radiation Induced X-Ray Emission (SRIXE)

    SciTech Connect

    Jones, Keith W.

    1999-09-01

    Elemental analysis using emission of characteristic x rays is a well-established scientific method. The success of this analytical method is highly dependent on the properties of the source used to produce the x rays. X-ray tubes have long existed as a principal excitation source, but electron and proton beams have also been employed extensively. The development of the synchrotron radiation x-ray source that has taken place during the past 40 years has had a major impact on the general field of x-ray analysis. Even tier 40 years, science of x-ray analysis with synchrotron x-ray beams is by no means mature. Improvements being made to existing synchrotron facilities and the design and construction of new facilities promise to accelerate the development of the general scientific use of synchrotron x-ray sources for at least the next ten years. The effective use of the synchrotron source technology depends heavily on the use of high-performance computers for analysis and theoretical interpretation of the experimental data. Fortunately, computer technology has advanced at least as rapidly as the x-ray technology during the past 40 years and should continue to do so during the next decade. The combination of these technologies should bring about dramatic advances in many fields where synchrotron x-ray science is applied. It is interesting also to compare the growth and rate of acceptance of this particular research endeavor to the rates for other technological endeavors. Griibler [1997] cataloged the time required for introduction, diffusion,and acceptance of technological, economic, and social change and found mean values of 40 to 50 years. The introduction of the synchrotron source depends on both technical and non-technical factors, and the time scale at which this seems to be occurring is quite compatible with what is seen for other major innovations such as the railroad or the telegraph. It will be interesting to see how long the present rate of technological change

  1. High-average-power water window soft X-rays from an Ar laser plasma

    NASA Astrophysics Data System (ADS)

    Amano, Sho

    2016-07-01

    A high average power of 140 mW and high conversion efficiency of 14% were demonstrated in “water window” soft X-rays generated using a laser plasma source developed in-house, when a solid Ar target was irradiated by a commercial Nd:YAG Q-switched laser with an energy of 1 J at a repetition rate of 1 Hz. This soft X-ray power compared favorably with that produced using a synchrotron radiation source, and the developed laser plasma source can be used in various applications, such as soft X-ray microscopy, in place of synchrotron facilities.

  2. A soft X-ray lag detected in Centaurus A

    NASA Astrophysics Data System (ADS)

    Tachibana, Yutaro; Kawamuro, Taiki; Ueda, Yoshihiro; Shidatsu, Megumi; Arimoto, Makoto; Yoshii, Taketoshi; Yatsu, Yoichi; Saito, Yoshihiko; Pike, Sean; Kawai, Nobuyuki

    2016-06-01

    We performed time-lag analysis on the X-ray light curves of Centaurus A (Cen A) obtained by the Gas Slit Camera (GSC) aboard the Monitor of All-sky X-ray Image (MAXI) in three energy bands (2-4 keV, 4-10 keV, and 10-20 keV). We discovered a soft X-ray lag relative to higher energies (soft lag) on a timescale of days in a flaring episode by employing the discrete correlation function (DCF) and the z-transformed discrete correlation function (ZDCF) method. In the episode, a peak and a centroid in the DCF and the ZDCF was observed at a soft lag of ˜ 5 d in 2-4 keV versus 4-10 keV and in 4-10 keV versus 10-20 keV, and ˜ 10 d in 2-4 keV versus 10-20 keV. We found it difficult to explain the observed X-ray variation by a single energy injection with the one-zone synchrotron self-Compton (SSC) model, in which the soft lags in these three energy bands reflect the different cooling times of the relativistic electrons, by assuming the magnetic field and minimum Lorentz factor estimated from a broad-band spectral energy distribution. Alternatively, if the phenomenon is interpreted as cooling of Comptonizing electrons in a corona covering the accretion disk, the temperature of the corona producing the variable X-rays should be ˜ 10 keV for reconciliation with the soft lag in the energy range of 2-20 keV.

  3. Soft x-ray laser microscopy

    SciTech Connect

    DiCicco, D.; Meixler, L.; Skinner, C.H.; Suckewer, S.; Hirschberg, J.; Kohen, E.

    1987-12-31

    Microscopes based on soft X-ray lasers possess unique advantages in bridging the gap between high resolution electron microscopy of dehydrated, stained cells and light microscopy at comparatively low resolution of unaltered live cells. The high brightness and short pulse duration of soft X-ray lasers make them ideal for flash imaging of live specimens. The Princeton soft X-ray laser is based on a magnetically confined laser produced carbon plasma. Radiation cooling after the laser pulse produces rapid recombination which produces a population inversion and high gain. A full account is given in a companion paper in this volume. The important characteristics of the laser beam produced by this device are 1 to 3 mJ of 18.2 nm radiation in a 10 to 30 nsec pulse with a divergence of 5 mrad. The 18.2 nm wavelength, while outside the water window, does provide a factor of 3 difference in absorption coefficients between oxygen and carbon.

  4. Soft x-ray laser microscopy

    SciTech Connect

    DiCicco, D. ); Meixler, L.; Skinner, C.H.; Suckewer, S. . Plasma Physics Lab.); Hirschberg, J.; Kohen, E. . Dept. of Physics)

    1987-01-01

    Microscopes based on soft X-ray lasers possess unique advantages in bridging the gap between high resolution electron microscopy of dehydrated, stained cells and light microscopy at comparatively low resolution of unaltered live cells. The high brightness and short pulse duration of soft X-ray lasers make them ideal for flash imaging of live specimens. The Princeton soft X-ray laser is based on a magnetically confined laser produced carbon plasma. Radiation cooling after the laser pulse produces rapid recombination which produces a population inversion and high gain. A full account is given in a companion paper in this volume. The important characteristics of the laser beam produced by this device are 1 to 3 mJ of 18.2 nm radiation in a 10 to 30 nsec pulse with a divergence of 5 mrad. The 18.2 nm wavelength, while outside the water window, does provide a factor of 3 difference in absorption coefficients between oxygen and carbon.

  5. Application of pixel array detectors at x-ray synchrotrons.

    SciTech Connect

    Miceli, N.; X-Ray Science Division

    2009-03-01

    Pixel array detectors have only recently been seriously used at x-ray synchrotrons. We describe the application of a digital pixel array detector (Pilatus100k) to a variety of synchrotron experiments at the Advanced Photon Source at Argonne National Laboratory. The Pilatus100k was developed at the Paul Scherrer Institut (PSI). It has been commercialized by a PSI spinoff (Dectrics Ltd.) This is the first commercially available pixel array detector for x-ray synchrotron applications. The APS synchrotron provides tunable x-ray pulses with duration of {approx}80 ps and a repetition period of 153 ns (24-bunch mode). The Pilatus100k is a direct detection x-ray detector where each 172 micron pixel counts individual x-ray pulses above a lower threshold. It consists of {approx}100k pixels each of which is capable of single-photon counting (>3 keV) at count rates up to {approx}1 MHz. In addition, the Pilatus100k is an electronically gateable detector. We present data showing that the Pilatus100k is capable of isolating a single x-ray bunch at the APS in 24 bunch mode. We will also present a variety of different experiments exploiting the unique capabilities of the Pilatus100k.

  6. The Effect of X-Ray Absorption Fine Structure in Soft X-ray Astronomical Telescopes

    NASA Astrophysics Data System (ADS)

    Owens, Alan; Denby, Michael; Wells, Alan; Keay, Adam; Graessle, Dale E.; Blake, Richard L.

    1997-02-01

    Recent in-orbit measurements by high resolution soft X-ray telescopes have revealed low-level fine structure in target spectra that cannot be attributed to a celestial source. Ultimately, this can be traced to the ability of the new high spectral resolution silicon detectors to resolve X-ray absorption fine structure (XAFS) produced in the various detection subsystems. Based on measurements taken at the Daresbury Synchrotron Radiation Source (SRS) and the National Synchrotron Light Source (NSLS), we have modeled the full-up response function of the Joint European X-ray Telescope (JET-X), taking into account edge structure generated in the detectors, filters, and mirrors. It is found that unfolding celestial source spectra using a response function in which the detailed edge shapes are calculated from standard absorption cross sections leads to the generation of spectral artifacts at every absorption edge. These in turn produce unacceptably high values of χ2 in model fits for total source fluxes above ~4 × 104 counts. For JET-X, this corresponds to a source strength of ~0.4 millicrab observed for 105 s. Statistically significant ``linelike'' features are introduced into the derived source spectra with amplitudes as great as 10% of the source flux. For JET-X, these features rise above the 3 σ level for integral source exposures above ~5 × 104 source counts. The largest deviations in the residuals arise near 0.5 keV and 2.2 keV and are attributed to XAFS produced in the oxide surface layers of the CCD and the gold reflective surface of the mirrors, respectively. These results are significant for data interpretation tasks with the ASCA, JET-X, XMM, and Advanced X-Ray Astrophysics Facility (AXAF) telescopes.

  7. High-speed X-ray phase imaging and X-ray phase tomography with Talbot interferometer and white synchrotron radiation.

    PubMed

    Momose, Atsushi; Yashiro, Wataru; Maikusa, Hirohide; Takeda, Yoshihiro

    2009-07-20

    X-ray Talbot interferometry, which uses two transmission gratings, has the advantage that broad energy bandwidth x-rays can be used. We demonstrate the use of white synchrotron radiation for high-speed X-ray phase imaging and tomography in combination with an X-ray Talbot interferometer. The moiré fringe visibility over 20% was attained, enabling quantitative phase measurement. X-ray phase images with a frame rate of 500 f/s and an X-ray phase tomogram with a scan time of 0.5 s were obtained successfully. This result suggests a breakthrough for time-resolved three-dimensional observation of objects that weakly absorb X-rays, such as soft material and biological objects.

  8. Synchrotron x-ray modification of nanoparticle superlattice formation

    NASA Astrophysics Data System (ADS)

    Lu, Chenguang; Akey, Austin J.; Herman, Irving P.

    2012-09-01

    The synchrotron x-ray radiation used to perform small angle x-ray scattering (SAXS) during the formation of three-dimensional nanoparticle superlattices by drop casting nanoparticle solutions affects the structure and the local crystalline order of the resulting films. The domain size decreases due to the real-time SAXS analysis during drying and more macroscopic changes are visible to the eye.

  9. Soft x-ray holographic tomography for biological specimens

    NASA Astrophysics Data System (ADS)

    Gao, Hongyi; Chen, Jianwen; Xie, Honglan; Li, Ruxin; Xu, Zhizhan; Jiang, Shiping; Zhang, Yuxuan

    2003-10-01

    In this paper, we present some experimental results on X -ray holography, holographic tomography, and a new holographic tomography method called pre-amplified holographic tomography is proposed. Due to the shorter wavelength and the larger penetration depths, X-rays provide the potential of higher resolution in imaging techniques, and have the ability to image intact, living, hydrated cells w ithout slicing, dehydration, chemical fixation or stain. Recently, using X-ray source in National Synchrotron Radiation Laboratory in Hefei, we have successfully performed some soft X-ray holography experiments on biological specimen. The specimens used in the experiments was the garlic clove epidermis, we got their X-ray hologram, and then reconstructed them by computer programs, the feature of the cell walls, the nuclei and some cytoplasm were clearly resolved. However, there still exist some problems in realization of practical 3D microscopic imaging due to the near-unity refractive index of the matter. There is no X-ray optics having a sufficient high numerical aperture to achieve a depth resolution that is comparable to the transverse resolution. On the other hand, computer tomography needs a record of hundreds of views of the test object at different angles for high resolution. This is because the number of views required for a densely packed object is equal to the object radius divided by the desired depth resolution. Clearly, it is impractical for a radiation-sensitive biological specimen. Moreover, the X-ray diffraction effect makes projection data blur, this badly degrades the resolution of the reconstructed image. In order to observe 3D structure of the biological specimens, McNulty proposed a new method for 3D imaging called "holographic tomography (HT)" in which several holograms of the specimen are recorded from various illumination directions and combined in the reconstruction step. This permits the specimens to be sampled over a wide range of spatial

  10. Soft X-Ray Laser Development

    DTIC Science & Technology

    1989-10-01

    AND SUBTrI 5 . FUNDING NUMBERS Soft X-ray Laser Development 61102F/2301/A8 L AUTHOR(S) ( Szymon Suckewer 7. PERFORMING ORGANIZATION NAME(S) AND ADORESS...diDr-uinteg~uior Slack 5 . Funding Numbers. To include contract a-d5( fcanTehil and grant numtners; may include programn Reports. element number(s...g~m x 5 mm line-focus on a length-varying cylindrical target. The target lengths used in this experiment were 1, 2.5, and 4.5 mm ( limited by the

  11. Soft X-ray Microscopy of Green Cements

    SciTech Connect

    Monteiro, P. J. M.; Mancio, M.; Chae, R.; Ha, J.; Kirchheim, A. P.; Fischer, P.; Tyliszczak, T.

    2011-09-09

    The present status of the cement and concrete industry is not sustainable. The production of Portland cement is responsible for 7% of the CO{sub 2} emissions in the world and existing reinforced concrete infrastructure is deteriorating at a fast pace. The change in the existing technology requires new developments in our understanding of the nanostructure of hydration products and the complex deterioration reactions. We have been developing an elaborate research program to advance the existing cement and concrete science by characterizing its nanostructure by synchrotron radiation. A new generation of green cements is being studied using high-resolution soft x-ray microscopy at the nano-level.

  12. Dynamical diffraction imaging (topography) with X-ray synchrotron radiation

    NASA Technical Reports Server (NTRS)

    Kuriyama, M.; Steiner, B. W.; Dobbyn, R. C.

    1989-01-01

    By contrast to electron microscopy, which yields information on the location of features in small regions of materials, X-ray diffraction imaging can portray minute deviations from perfect crystalline order over larger areas. Synchrotron radiation-based X-ray optics technology uses a highly parallel incident beam to eliminate ambiguities in the interpretation of image details; scattering phenomena previously unobserved are now readily detected. Synchrotron diffraction imaging renders high-resolution, real-time, in situ observations of materials under pertinent environmental conditions possible.

  13. Synchrotron X-ray footprinting on tour

    PubMed Central

    Bohon, Jen; D’Mello, Rhijuta; Ralston, Corie; Gupta, Sayan; Chance, Mark R.

    2014-01-01

    Synchrotron footprinting is a valuable technique in structural biology for understanding macromolecular solution-state structure and dynamics of proteins and nucleic acids. Although an extremely powerful tool, there is currently only a single facility in the USA, the X28C beamline at the National Synchrotron Light Source (NSLS), dedicated to providing infrastructure, technology development and support for these studies. The high flux density of the focused white beam and variety of specialized exposure environments available at X28C enables footprinting of highly complex biological systems; however, it is likely that a significant fraction of interesting experiments could be performed at unspecialized facilities. In an effort to investigate the viability of a beamline-flexible footprinting program, a standard sample was taken on tour around the nation to be exposed at several US synchrotrons. This work describes how a relatively simple and transportable apparatus can allow beamlines at the NSLS, CHESS, APS and ALS to be used for synchrotron footprinting in a general user mode that can provide useful results. PMID:24365913

  14. Soft X-ray photoemission studies of Hf oxidation

    SciTech Connect

    Suzer, S.; Sayan, S.; Banaszak Holl, M.M.; Garfunkel, E.; Hussain, Z.; Hamdan, N.M.

    2002-02-01

    Soft X-Ray Photoemission Spectroscopy using surface sensitive Synchrotron Radiation has been applied to accurately determine the binding energy shifts and the valence band offset of the HfO2 grown on Hf metal. Charging of oxide films under x-rays (or other irradiation) is circumvented by controlled and sequential in-situ oxidation. Photoemission results show the presence of metallic Hf (from the substrate) with the 4f7/2 binding energy of 14.22 eV, fully oxidized Hf (from HfO2) with the 4f7/2 binding energy of 18.16 eV, and at least one clear suboxide peak. The position of the valence band of HfO2 with respect to the Hf(m) Fermi level is determined as 4.05 eV.

  15. Resonant soft X-ray diffraction - in extremis.

    PubMed

    Hatton, P D; Wilkins, S B; Beale, T A W; Johal, T K; Prabhakaran, D; Boothroyd, A T

    2005-07-01

    The use of softer-energy X-rays produced by synchrotron radiation for diffraction is an area of current interest. In this paper, experiments exploiting resonant scattering at the L absorption edges of 3d transition metal elements are reported. Such energies, typically 500-1000 eV, are at the extreme limit of soft X-ray diffraction where absorption effects are so severe that the sample and diffractometer must be placed in a windowless high-vacuum vessel. In addition, the Ewald sphere is so small as to likely contain, at most, only a single Bragg reflection. Advantages of using such radiation for the study of weak diffraction effects such as anomalous scattering, charge ordering, magnetic diffraction and orbital ordering are reported.

  16. Resonant soft X-ray scattering for polymer materials

    DOE PAGES

    Liu, Feng; Brady, Michael A.; Wang, Cheng

    2016-04-16

    Resonant Soft X-ray Scattering (RSoXS) was developed within the last few years, and the first dedicated resonant soft X-ray scattering beamline for soft materials was constructed at the Advanced Light Source, LBNL. RSoXS combines soft X-ray spectroscopy with X-ray scattering and thus offers statistical information for 3D chemical morphology over a large length scale range from nanometers to micrometers. Using RSoXS to characterize multi-length scale soft materials with heterogeneous chemical structures, we have demonstrated that soft X-ray scattering is a unique complementary technique to conventional hard X-ray and neutron scattering. Its unique chemical sensitivity, large accessible size scale, molecular bondmore » orientation sensitivity with polarized X-rays, and high coherence have shown great potential for chemically specific structural characterization for many classes of materials.« less

  17. Resonant soft X-ray scattering for polymer materials

    SciTech Connect

    Liu, Feng; Brady, Michael A.; Wang, Cheng

    2016-04-16

    Resonant Soft X-ray Scattering (RSoXS) was developed within the last few years, and the first dedicated resonant soft X-ray scattering beamline for soft materials was constructed at the Advanced Light Source, LBNL. RSoXS combines soft X-ray spectroscopy with X-ray scattering and thus offers statistical information for 3D chemical morphology over a large length scale range from nanometers to micrometers. Using RSoXS to characterize multi-length scale soft materials with heterogeneous chemical structures, we have demonstrated that soft X-ray scattering is a unique complementary technique to conventional hard X-ray and neutron scattering. Its unique chemical sensitivity, large accessible size scale, molecular bond orientation sensitivity with polarized X-rays, and high coherence have shown great potential for chemically specific structural characterization for many classes of materials.

  18. Characterization of Biomaterials by Soft X-Ray Spectromicroscopy

    PubMed Central

    Leung, Bonnie O.; Brash, John L.; Hitchcock, Adam P.

    2010-01-01

    Synchrotron-based soft X-ray spectromicroscopy techniques are emerging as useful tools to characterize potentially biocompatible materials and to probe protein interactions with model biomaterial surfaces. Simultaneous quantitative chemical analysis of the near surface region of the candidate biomaterial, and adsorbed proteins, peptides or other biological species can be obtained at high spatial resolution via scanning transmission X-ray microscopy (STXM) and X-ray photoemission electron microscopy (X-PEEM). Both techniques use near-edge X-ray absorption fine structure (NEXAFS) spectral contrast for chemical identification and quantitation. The capabilities of STXM and X-PEEM for the analysis of biomaterials are reviewed and illustrated by three recent studies: (1) characterization of hydrophobic surfaces, including adsorption of fibrinogen (Fg) or human serum albumin (HSA) to hydrophobic polymeric thin films, (2) studies of HSA adsorption to biodegradable or potentially biocompatible polymers, and (3) studies of biomaterials under fully hydrated conditions. Other recent applications of STXM and X-PEEM to biomaterials are also reviewed.

  19. Radiobiological studies using synchrotron-produced ultrasoft X-rays.

    PubMed

    Gould, M N; Nelms, B E; Hill, C K; Mackay, J F; Lindstrom, M J; Mackie, T R; Deluca, P M

    1999-12-01

    Ultrasoft X-rays have been extensively used to explore radiobiological mechanisms surrounding cell killing. These studies for the most part have been linked to a small number of X-ray energies. Recently, this field of study has been broadened by the availability of synchrotron-produced ultrasoft X-rays which can be produced at any desired energy. We have taken advantage of the University of Wisconsin Synchrotron to reexamine two fundamental radiobiological questions: Dose RBE vary with different ultrasoft X-ray energies? Dose the fraction of the nuclear volume exposed to equal total X-ray energy modify cell cytotoxicity? The first study focuses on the survival of Chinese hamster V79 and mouse C3H10T1/2 cells irradiated with synchrotron-produced 273 eV and 860 eV ultrasoft X-rays. These two energies, which are available by multilayer monochromatization of the synchrotron output spectrum, exhibit equal attenuation within living cells. Such an isoattenuating energy pair allows the direct examination of how biological effectiveness varies with the energy of the ultrasoft X-rays. In comparing survival results, we find similar biological effectiveness of these two energies for both the C3H10T1/2 and the V79 cells. These results are no consistent with previous findings of increasing RBE with decreasing ultrasoft X-ray energies. In addition, after correcting for mean nuclear based on measurements of cell thickness obtained with confocal microscopy, we find no significant differences in survival between the two ultrasoft X-ray energies and 250 kVp X-rays. These results suggest that RBE does not increase with decreasing energy of ultrasoft X-ray between 860 eV and 273 eV. In a second study we introduced an method which allows partial-volume irradiation of live cells using synchrotron-produced ultrasoft X-rays and micro-fabricated irradiation masks. The masks were made by X-ray lithography at the University of Wisconsin Synchrotron Radiation Center, and they consist of 1

  20. Ultra-high vacuum compatible optical chopper system for synchrotron x-ray scanning tunneling microscopy

    SciTech Connect

    Chang, Hao; Cummings, Marvin; Shirato, Nozomi; Stripe, Benjamin; Preissner, Curt; Freeland, John W.; Rosenmann, Daniel; Kersell, Heath; Hla, Saw-Wai; Rose, Volker

    2016-01-28

    High-speed beam choppers are a crucial part of time-resolved x-ray studies as well as a necessary component to enable elemental contrast in synchrotron x-ray scanning tunneling microscopy (SX-STM). However, many chopper systems are not capable of operation in vacuum, which restricts their application to x-ray studies with high photon energies, where air absorption does not present a significant problem. To overcome this limitation, we present a fully ultra-high vacuum (UHV) compatible chopper system capable of operating at variable chopping frequencies up to 4 kHz. The lightweight aluminum chopper disk is coated with Ti and Au films to provide the required beam attenuation for soft and hard x-rays with photon energies up to about 12 keV. The chopper is used for lock-in detection of x-ray enhanced signals in SX-STM.

  1. X-Ray microanalytical techniques based on synchrotron radiation.

    PubMed

    Snigireva, Irina; Snigirev, Anatoly

    2006-01-01

    The development of 3rd generation synchrotron radiation sources like European Synchrotron Radiation Facility (ESRF) in parallel with recent advances in the technology of X-ray microfocusing elements like Kirkpatrick-Baez (KB) mirrors, diffractive (Fresnel zone plates, FZP) and refractive (compound refractive lenses, CRL) optics, makes it possible to use X-ray microscopy techniques with high energy X-rays (energy superior to 4 keV). Spectroscopy, imaging, tomography and diffraction studies of samples with hard X-rays at micrometre and sub-micrometre spatial resolutions are now possible. The concept of combining these techniques as a high-energy microscopy has been proposed and successfully realized at the ESRF beamlines. Therefore a short summary of X-ray microscopy techniques is presented first. The main emphasis will be put on those methods which aim to produce sub-micron and nanometre resolution. These methods fall into three broad categories: reflective, refractive and diffractive optics. The basic principles and recent achievements will be discussed for all optical devices. Recent applications of synchrotron based microanalytical techniques to characterise radioactive fuel particles (UO(2)) released from the Chernobyl reactor are reported.

  2. White-light spacial frequency multiplication using soft x rays

    NASA Astrophysics Data System (ADS)

    Wei, Max; Gullikson, Eric M.; Underwood, James H.; Gustafson, T. Kenneth; Attwood, David T., Jr.

    1995-09-01

    We have patterned a 0.25-micron period grating in SAL-601 photoresist using soft x-ray white-light spatial frequency multiplication. The configuration is that of a grating interferometer using two transmission gratings having the same period ((Lambda) equals 0.5 micron) and fabricated by electron beam lithography and lift-off. The first transmission grating splits an incoming x-ray beam into two paths and the second grating, operating in higher order, combines the two beams. A standing wave pattern is obtained at the intersection of the two beams and recorded by a photoresist coated substrate. This patterning technique has the advantage of multiplying the spatial frequency of the interferometer gratings by an even integer factor. Furthermore, the recording geometry is insensitive to both the longitudinal and transverse coherence of the illumination. Synchrotron bending magnet radiation from the advanced light source located at the Lawrence Berkeley National Laboratory was used as the source. The grating interferometer geometry has been used in the past to record white-light interference fringes using visible and ultraviolet light sources. We have used a two-grating interferometer to provide an initial demonstration of white-light spatial frequency doubling at soft x-ray wavelengths. By using this technique with shorter period parent gratings, it should be possible to patten gratings with higher resolution than electron beam lithography.

  3. Synchrotron X-ray emission from old pulsars

    NASA Astrophysics Data System (ADS)

    Kisaka, Shota; Tanaka, Shuta J.

    2014-09-01

    We study the synchrotron radiation as the observed non-thermal emission by the X-ray satellites from old pulsars (≳1-10 Myr) to investigate the particle acceleration in their magnetospheres. We assume that the power-law component of the observed X-ray spectra is caused by the synchrotron radiation from electrons and positrons in the magnetosphere. We consider two pair-production mechanisms of X-ray emitting particles, the magnetic and the photon-photon pair productions. High-energy photons, which ignite the pair production, are emitted via the curvature radiation of the accelerated particles. We use the analytical description for the radiative transfer and estimate the luminosity of the synchrotron radiation. We find that for pulsars with the spin-down luminosity Lsd ≲ 1033 erg s-1, the locations of the particle acceleration and the non-thermal X-ray emission are within ≲107 cm from the centre of the neutron star, where the magnetic pair production occurs. For pulsars with the spin-down luminosity Lsd ≲ 1031 erg s-1 such as J0108-1431, the synchrotron radiation is difficult to explain the observed non-thermal component even if we consider the existence of the strong and small-scale surface magnetic field structures.

  4. SYNCHROTRON X - RAY OBSERVATIONS OF A MONOLAYER TEMPLATE FOR MINERALIZATION.

    SciTech Connect

    DIMASI,E.; GOWER,L.B.

    2000-11-27

    Mineral nucleation at a Langmuir film interface has been studied by synchrotron x-ray scattering. Diluted calcium bicarbonate solutions were used as subphases for arachidic and stearic acid monolayers, compressed in a Langmuir trough. Self-assembly of the monolayer template is observed directly, and subsequent crystal growth monitored in-situ.

  5. Hard X-ray Sources for the Mexican Synchrotron Project

    NASA Astrophysics Data System (ADS)

    Reyes-Herrera, Juan

    2016-10-01

    One of the principal tasks for the design of the Mexican synchrotron was to define the storage ring energy. The main criteria for choosing the energy come from studying the electromagnetic spectrum that can be obtained from the synchrotron, because the energy range of the spectrum that can be obtained will determine the applications available to the users of the future light source. Since there is a public demand of hard X-rays for the experiments in the synchrotron community users from Mexico, in this work we studied the emission spectra from some hard X-ray sources which could be the best options for the parameters of the present Mexican synchrotron design. The calculations of the flux and the brightness for one Bending Magnet and four Insertion Devices are presented; specifically, for a Superconducting Bending Magnet (SBM), a Superconducting Wiggler (SCW), an In Vacuum Short Period Undulator (IV-SPU), a Superconducting Undulator (SCU) and for a Cryogenic Permanent Magnet Undulator (CPMU). Two commonly available synchrotron radiation programs were used for the computation (XOP and SRW). From the results, it can be concluded that the particle beam energy from the current design is enough to have one or more sources of hard X-rays. Furthermore, a wide range of hard X-ray region can be covered by the analyzed sources, and the choice of each type should be based on the specific characteristics of the X-ray beam to perform the experiments at the involved beamline. This work was done within the project Fomix Conacyt-Morelos ”Plan Estrategico para la construccion y operación de un Sincrotron en Morelos” (224392).

  6. High repetition rate laser produced soft x-ray source for ultrafast x-ray absorption near edge structure measurements.

    PubMed

    Fourmaux, S; Lecherbourg, L; Harmand, M; Servol, M; Kieffer, J C

    2007-11-01

    Recent progress in high intensity ultrafast laser systems provides the opportunity to produce laser plasma x-ray sources exhibiting broad spectrum and high average x-ray flux that are well adapted to x-ray absorption measurements. In this paper, the development of a laser based x-ray absorption near edge structure (XANES) beamline exhibiting high repetition rate by using the Advanced Laser Light Source (ALLS) facility 100 Hz laser system (100 mJ, 35 fs at 800 nm) is presented. This system is based on a broadband tantalum solid target soft x-ray source and a grazing incidence grating spectrometer in the 1-5 nm wavelength range. To demonstrate the high potential of this laser based XANES technique in condensed matter physics, material science, or biology, measurements realized with several samples are presented: VO2 vanadium L edge, Si3N4 nitrogen K edge, and BPDA/PPD polyimide carbon K edge. The characteristics of this laser based beamline are discussed in terms of brightness, signal to noise ratio, and compared to conventional synchrotron broadband x-ray sources which allow achieving similar measurements. Apart from the very compact size and the relative low cost, the main advantages of such a laser based soft x-ray source are the picosecond pulse duration and the perfect synchronization between this x-ray probe and a laser pulse excitation which open the way to the realization of time resolved x-ray absorption measurements with picosecond range time resolution to study the dynamics of ultrafast processes and phase transition.

  7. High repetition rate laser produced soft x-ray source for ultrafast x-ray absorption near edge structure measurements

    SciTech Connect

    Fourmaux, S.; Lecherbourg, L.; Harmand, M.; Servol, M.; Kieffer, J. C.

    2007-11-15

    Recent progress in high intensity ultrafast laser systems provides the opportunity to produce laser plasma x-ray sources exhibiting broad spectrum and high average x-ray flux that are well adapted to x-ray absorption measurements. In this paper, the development of a laser based x-ray absorption near edge structure (XANES) beamline exhibiting high repetition rate by using the Advanced Laser Light Source (ALLS) facility 100 Hz laser system (100 mJ, 35 fs at 800 nm) is presented. This system is based on a broadband tantalum solid target soft x-ray source and a grazing incidence grating spectrometer in the 1-5 nm wavelength range. To demonstrate the high potential of this laser based XANES technique in condensed matter physics, material science, or biology, measurements realized with several samples are presented: VO{sub 2} vanadium L edge, Si{sub 3}N{sub 4} nitrogen K edge, and BPDA/PPD polyimide carbon K edge. The characteristics of this laser based beamline are discussed in terms of brightness, signal to noise ratio, and compared to conventional synchrotron broadband x-ray sources which allow achieving similar measurements. Apart from the very compact size and the relative low cost, the main advantages of such a laser based soft x-ray source are the picosecond pulse duration and the perfect synchronization between this x-ray probe and a laser pulse excitation which open the way to the realization of time resolved x-ray absorption measurements with picosecond range time resolution to study the dynamics of ultrafast processes and phase transition.

  8. Technology development for soft X-ray spectroscopy

    NASA Astrophysics Data System (ADS)

    Törmä, P. T.; Sipilä, H. J.; Koskinen, T.; Mattila, M.

    2016-05-01

    X-ray spectroscopy instruments lose part of their performance due to the lack of suitable components for soft X-ray region below 1 keV. Therefore, in the analysis of low atomic number elements including lithium, beryllium, boron and carbon instrument sensitivity is often limited. In this work we describe how the performance of the spectroscopy of soft X-rays is significantly improved when all devices integrated in the spectroscopic instrument are suitable for both soft and hard X-rays. This concept is based on utilizing ultra-thin SiN X-ray windows with proven performance not only as a detector window but also as an X-ray source window. By including a soft-X-ray-sensitive silicon drift detector with efficient surface charge collection in this concept the sensitivity and performance of the instrument is significantly increased.

  9. Soft x-ray holography and microscopy of biological cells

    NASA Astrophysics Data System (ADS)

    Chen, Jianwen; Gao, Hongyi; Xie, Honglan; Li, Ruxin; Xu, Zhizhan

    2003-10-01

    Some experimental results on soft X-ray microscopy and holography imaging of biological specimens are presented in the paper. As we know, due to diffraction effects, there exists a resolution limit determined by wavelength λ and numerical aperture NA in conventional optical microscopy. In order to improve resolution, the num erical aperture should be made as large as possible and the wavelength as short as possible. Owing to the shorter wavelength, X-rays provide the potential of higher resolution in X-ray microscopy, holography image and allow for exam ination the interior structures of thicker specimens. In the experiments, we used synchrotron radiation source in Hefei as light source. Soft X-rays come from a bending magnet in 800 M eV electron storage ring with characteristic wavelength of 2.4 nm. The continuous X-ray spectrums are monochromatized by a zone-plate and a pinhole with 300 m diameter. The experimental set-up is typical contact microscopic system, its main advantage is simplicity and no special optical element is needed. The specimens used in the experiments of microscopic imaging are the colibacillus, the gingko vascular hundle and the fritillaries ovary karyon. The specimen for holographic imaging is the spider filam ents. The basic structures of plant cells such as the cell walls, the cytoplasm and the karyon especially the joint structures between the cells are observed clearly. An experimental study on a thick biological specimen that is a whole sporule w ith the thickness of about 30 μm is performed. In the holographic experiments, the experimental setup is typical Gabor in-line holography. The specimen is placed in line with X-ray source, which provides both the reference w aves and specimen illum ination. The specimen is some spider filament, which adhere to a Si3N4 film. The recording medium is PM M A, which is placed at recording distance of about 400 μm from the specimen. The hologram s were reconstructed by digital method with 300 nm

  10. Soft X-ray Spectromicroscopy of Polymers

    NASA Astrophysics Data System (ADS)

    Ade, Harald

    1997-03-01

    The development of Near Edge X-ray Absorption Fine Structure (NEXAFS) microscopy^1 and linear dichroism microscopy^2 over the last few years utilizing the X1-Scanning Transmission X-ray Microscope (X1-STXM) at the National Synchrotron Light Source provides excellent specificity to various functional groups and moieties in organic molecules and polymeric materials at a spatial resolution of 50 nm. This chemical specificity can be utilized to map the distribution of various compounds in a material, or to micro-chemically analyze small sample areas. Examples of applications include the study of various phase-separated polymers (polyurethanes, liquid crystalline polyesters), multicomponent polymer blends, polymer laminates, and other organic materials such as coal^3. Linear dichroism microscopy furthermore explores the polarization dependence of NEXAFS in (partially) oriented materials, and can determine the orientation of specific functional groups. Applications of linear dichroism microscopy have focused so far on determining the relative degree of radial orientation in Kevlar fibers^3. ^1 H. Ade, X. Zhang, S. Cameron, C. Costello, J. Kirz, and S. Williams, Science 258, 972 (1992). ^2 H. Ade and B. Hsiao, Science 262, 1427 (1993). ^3 Acknowledgement: My callaborators are B. Hsiao, S. Subramoney, B. Wood, I. Plotzker, E. Rightor, G. Mitchell, C. Sloop, D.-J. Liu, S.-C. Liu, J. Marti, C. Zimba, A. P. Smith, R. Spontak, R. Fornes, R. Gilbert, C. Cody, A. Hitchcock and S. Urquhart. The X1-STXM is built and maintained by J. Kirz and C. Jacobsen and their groups. Work supported by: NSF Young Investigator Award (DMR-9458060), DuPont Young Professor Grant, and Dow Chemical.

  11. Applications of synchrotron x-ray fluorescence to extraterrestrial materials

    SciTech Connect

    Sutton, S.R.; Rivers, M.L.; Smith, J.V.

    1986-01-01

    Synchrotron x-ray fluorescence (SXRF) is a valuable technique for trace element analyses of extraterrestrial materials permitting minimum detection limits less than 1 ppM for 20 micrometer spots. SXRF measurements have been performed on iron meteorites and micrometeorites using white synchrotron radiation and an energy dispersive x-ray detector at the National Synchrotron Light Source (X-26C), Brookhaven National Laboratory (NY). Partitioning of Cu between troilite (FeS) and metal in the nine iron meteorites studied suggests sub-solidus re-equilibration in these objects. A technique has been developed for determining self-absorption corrections for filtered, continuum excitation of small specimens, such as stratospheric particles and refractory inclusions in meteorites.

  12. Tunable Soft X-Ray Oscillators

    SciTech Connect

    Wurtele, Jonathan; Gandhi, Punut; Gu, X-W; Fawley, William M; Reinsch, Matthia; Penn, Gregory; Kim, K-J; Lindberg, Ryan; Zholents, Alexander

    2010-09-17

    A concept for a tunable soft x-ray free electron laser (FEL) photon source is presented and studied numerically. The concept is based on echo-enabled harmonic generation (EEHG), wherein two modulator-chicane sections impose high harmonic structure with much greater efficacy as compared to conventional high harmonic FELs that use only one modulator-chicane section. The idea proposed here is to replace the external laser power sources in the EEHG modulators with FEL oscillators, and to combine the bunching of the beam with the production of radiation. Tunability is accomplished by adjusting the magnetic chicanes while the two oscillators remain at a fixed frequency. This scheme eliminates the need to develop coherent sources with the requisite power, pulse length, and stability requirements by exploiting the MHz bunch repetition rates of FEL continuous wave (CW) sources driven by superconducting (SC) linacs. We present time-dependent GINGER simulation results for an EEHG scheme with an oscillator modulator at 43 nm employing 50percent reflective dielectric mirrors and a second modulator employing an external, 215-nm drive laser. Peak output of order 300 MW is obtained at 2.7 nm, corresponding to the 80th harmonic of 215 nm. An alternative single-cavity echo-oscillator scheme based on a 13.4 nm oscillator is investigated with time-independent simulations that a 180-MW peak power at final wavelength of 1.12 nm. Three alternate configurations that use separate bunches to produce the radiation for EEHG microbunching are also presented. Our results show that oscillator-based soft x-ray FELs driven by CWSC linacs are extremely attractive because of their potential to produce tunable radiation at high average power together with excellent longitudinal coherence and narrow spectral bandwidth.

  13. A Sealed, UHV Compatible, Soft X-ray Detector Utilizing Gas Electron Multipliers

    SciTech Connect

    Schaknowski, N.A.; Smith, G.

    2009-10-25

    An advanced soft X-ray detector has been designed and fabricated for use in synchrotron experiments that utilize X-ray absorption spectroscopy in the study a wide range of materials properties. Fluorescence X-rays, in particular C{sub K} at 277eV, are converted in a low pressure gas medium, and charge multiplication occurs in two gas electron multipliers, fabricated in-house from glass reinforced laminate, to enable single photon counting. The detector satisfies a number of demanding characteristics often required in synchrotron environments, such as UHV compatibility compactness, long-term stability, and energy resolving capability.

  14. A soft X-ray image of the moon

    NASA Technical Reports Server (NTRS)

    Schmitt, J. H. M. M.; Aschenbach, B.; Hasinger, G.; Pfeffermann, E.; Snowden, S. L.

    1991-01-01

    A soft X-ray image of the moon obtained by the Roentgen Observatory Satellite ROSAT clearly shows a sunlit crescent, demonstrating that the moon's X-ray luminosity arises from backscattering of solar X-rays. The moon's optically dark side is also X-ray dark, and casts a distinct shadow on the diffuse cosmic X-ray background. Unexpectedly, the dark side seems to emit X-rays at a level about one percent of that of the bright side; this emission very probably results from energetic solar-wind electrons striking the moon's surface.

  15. Effects of Galactic absorption on soft X-ray surveys

    NASA Technical Reports Server (NTRS)

    Zamorani, G.; Gioia, I. M.; Maccacaro, T.; Wolter, A.

    1988-01-01

    A bias in the spectral distribution of X-ray sources detected in X-ray surveys is discussed which is due to the combination of the intrinsic characteristics of X-ray telescopes and the effects of low-energy photoelectric absorption within the Galaxy. A statistical method for obtaining information on the average spectrum of X-ray sources detected in well-defined surveys is presented. This method can be applied to surveys performed with X-ray telescopes working at relatively soft X-ray energies, such as Einstein, Exosat, and Rosat.

  16. SYNCHROTRON X-RAY BASED CHARACTERIZATION OF CDZNTE CRYSTALS

    SciTech Connect

    Duff, M

    2006-09-28

    Synthetic CdZnTe or 'CZT' crystals can be used for the room temperature-based detection of {gamma}-radiation. Structural/morphological heterogeneities within CZT, such as twinning, inclusions, and polycrystallinity can affect detector performance. We used a synchrotron-based X-ray technique, specifically extended X-ray absorption fine-structure (EXAFS) spectroscopy, to determine whether there are differences on a local structural level between intact CZT of high and low radiation detector performance. These studies were complemented by data on radiation detector performance and transmission IR imaging. The EXAFS studies revealed no detectable local structural differences between the two types of CZT materials.

  17. An X-ray microprobe facility using synchrotron radiation.

    PubMed

    Gordon, B M; Jones, K W; Hanson, A L; Pounds, J G; Rivers, M L; Spanne, P; Sutton, S R

    1990-01-01

    An X-ray microprobe for trace elemental analysis at micrometer spatial resolutions, using synchrotron radiation (SR), is under development. The facility consists of two beamlines, one including a 1:1 focusing mirror and the other an 8:1 ellipsoidal mirror. At present, "white light" is used for excitation of the characteristic X-ray fluorescence lines. Sensitivities in thin biological samples are in the range of 2-20 fg in 100 microns2 areas in 5 min irradiation times. Scanning techniques, as well as microtomography and chemical speciation, are discussed. Application to a specific biomedical study is included.

  18. An x-ray microprobe facility using synchrotron radiation

    SciTech Connect

    Gordon, B.M.; Jones, K.W.; Hanson, A.L.; Pounds, J.G.; Rivers, M.L.; Spanne, P.; Sutton, S.R.

    1989-01-01

    A x-ray microprobe for trace elemental analysis at micrometer spatial resolutions using synchrotron radiation (SR) is under development. The facility consists of two beamlines, one including a 1:1 focusing mirror and the other an 8:1 ellipsoidal mirror. At present ''white light''' is used for excitation of the characteristic x-ray fluorescence lines. Sensitivities in thin biological samples are in the range of 2-20 fg in 100 ..mu..m/sup 2/ areas in 5 min irradiation times. Scanning techniques as well as microtomography and chemical speciation are discussed. Application to a specific biomedical study is included. 13 refs., 2 figs.

  19. Rapid combinatorial screening by synchrotron X-ray imaging

    NASA Astrophysics Data System (ADS)

    Eba, Hiromi; Sakurai, Kenji

    2006-01-01

    An X-ray imaging system, which does not require any scans of the sample or an X-ray beam and which, therefore, dramatically reduces the amount of time required, was employed to evaluate combinatorial libraries efficiently. Two-dimensional X-ray fluorescence (XRF) images of an 8 mm × 8 mm area were observed for combinatorial substrates of manganese-cobalt spinel MnCo 2O 4 and lithium ferrite LiFeO 2 via an exposure time of 1-3 s using synchrotron X-rays. Thus, XRF signals from a whole substrate could be observed at once in a short space of time. In order to observe the chemical environment simultaneously for all materials arranged on the substrate, the fluorescent X-ray absorption fine structure (XAFS) was measured by repeating the imaging during the monochromator scans across the absorption edge for metals. This is extremely efficient because XAFS spectra for all materials placed on the common substrate are obtained from only a single energy scan. One can determine the valence numbers, as well as other aspects of the chemical environment of the metal included in each material, from the differences in spectral features and the energy shifts. Hence, combinatorial libraries can be screened very rapidly, and therefore efficiently, using the X-ray imaging system.

  20. Dante Soft X-ray Power Diagnostic for NIF

    SciTech Connect

    Dewald, E; Campbell, K; Turner, R; Holder, J; Landen, O; Glenzer, S; Kauffman, R; Suter, L; Landon, M; Rhodes, M; Lee, D

    2004-04-15

    Soft x-ray power diagnostics are essential for measuring spectrally resolved the total x-ray flux, radiation temperature, conversion efficiency and albedo that are important quantities for the energetics of indirect drive hohlraums. At the Nova or Omega Laser Facilities, these measurements are performed mainly with Dante, but also with DMX and photo-conductive detectors (PCD's). The Dante broadband spectrometer is a collection of absolute calibrated vacuum x-ray diodes, thin filters and x-ray mirrors used to measure the soft x-ray emission for photon energies above 50 eV.

  1. Laser produced plasma soft x-ray generation

    SciTech Connect

    Cerjan, C.; Rosen, M.D.

    1991-05-20

    The efficiency of soft x-ray production from laser-irradiated plasmas is simulated for two different spectral regions. These two regions, 14{Angstrom} {plus minus} 15% and 130{Angstrom} {plus minus} 1%, were chosen for proximity mask or point-projection technological applications. Relatively large conversion efficiencies were obtained from irradiation of a stainless steel target using the conditions suggested by recent Hampshire Instruments' experiments for proximity masking. Pulse-width and laser frequency parameter studies were performed for point-projection applications which suggest that the conversion applications which suggest that the conversion efficiency is sensitive to pulse-width but not to laser frequency. One of the critical components of any x-ray lithographic scheme is of course the x-ray laser source. There are two primary contenders for a reliable, efficient source currently: synchrotron radiation and spectral emission from laser produced plasma. The dominant issue for laser-plasma emission is the conversion efficiency -- output in the intended operating spectral region relative the required incident laser energy. Simulations are described in the following for both high and low energy spectral regions which have been suggested by either the proximity masking or point-projection technology.

  2. Synchrotron x-ray reflectivity study of oxidation/passivation of copper and silicon.

    SciTech Connect

    Chu, Y.; Nagy, Z.; Parkhutik, V.; You, H.

    1999-07-21

    Synchrotron x-ray-scattering technique studies of copper and silicon electrochemical interfaces are reported. These two examples illustrate the application of synchrotron x-ray techniques for oxidation, passivation, and dissolution of metals and semiconductors.

  3. Recent advances in synchrotron-based hard x-ray phase contrast imaging

    NASA Astrophysics Data System (ADS)

    Liu, Y.; Nelson, J.; Holzner, C.; Andrews, J. C.; Pianetta, P.

    2013-12-01

    Ever since the first demonstration of phase contrast imaging (PCI) in the 1930s by Frits Zernike, people have realized the significant advantage of phase contrast over conventional absorption-based imaging in terms of sensitivity to ‘transparent’ features within specimens. Thus, x-ray phase contrast imaging (XPCI) holds great potential in studies of soft biological tissues, typically containing low Z elements such as C, H, O and N. Particularly when synchrotron hard x-rays are employed, the favourable brightness, energy tunability, monochromatic characteristics and penetration depth have dramatically enhanced the quality and variety of XPCI methods, which permit detection of the phase shift associated with 3D geometry of relatively large samples in a non-destructive manner. In this paper, we review recent advances in several synchrotron-based hard x-ray XPCI methods. Challenges and key factors in methodological development are discussed, and biological and medical applications are presented.

  4. Applications of Synchrotron X-Rays in Microelectronics Industry Research

    SciTech Connect

    Jordan-Sweet, J.

    2005-01-10

    The high flux and density of x-rays produced at synchrotrons provide the microelectronics industry with a powerful probe of the structure and behavior of a wide array of solid materials that are being developed for use in devices of the future. They also are of great use in determining why currently-used materials and processes sometimes fail. This paper describes the X20 x-ray beamline facility operated by IBM at the National Synchrotron Light Source, and presents a series of three industry challenges and results that illustrate the variety of techniques used and problems addressed. The value of this research ranges from solving short-term, technically-specific problems to increasing our academic understanding of materials in general. Techniques discussed include high-resolution diffraction, time-resolved diffraction, texture measurements, and grazing-incidence diffraction.

  5. Application of X-ray synchrotron microscopy instrumentation in biology

    SciTech Connect

    Gasperini, F. M.; Pereira, G. R.; Granjeiro, J. M.; Calasans-Maia, M. D.; Rossi, A. M.; Perez, C. A.; Lopes, R. T.; Lima, I.

    2011-07-01

    X-ray micro-fluorescence imaging technique has been used as a significant tool in order to investigate minerals contents in some kinds of materials. The aim of this study was to evaluate the elemental distribution of calcium and zinc in bone substitute materials (nano-hydroxyapatite spheres) and cortical bones through X-Ray Micro-fluorescence analysis with the increment of Synchrotron Radiation in order to evaluate the characteristics of the newly formed bone and its interface, the preexisting bone and biomaterials by the arrangement of collagen fibers and its birefringence. The elemental mapping was carried out at Brazilian Synchrotron Light Laboratory, Campinas - Sao Paulo, Brazil working at D09-XRF beam line. Based on this study, the results suggest that hydroxyapatite-based biomaterials are biocompatible, promote osteo-conduction and favored bone repair. (authors)

  6. Synchrotron X-Ray Induced Gold Nanoparticle Formation

    SciTech Connect

    Yang, Y. C.; Wang, C. H.; Yang, T. Y.; Hwu, Y.; Chen, C. H.; Je, J. H.; Margaritondo, G.

    2007-01-19

    We reported a simple approach to generate gold nanoparticles from HAuCl4 containing aqueous solution by synchrotron x-ray irradiation at room temperature. The gold colloidal were investigated by a variety of characterization methods including Transmission Electron Microscope (TEM), Scanning Electron Microscope (SEM), Fourier transformation infrared (FTIR), Ultraviolet and Visible (UV-VIS) spectrometer and the effects of variables including pH value, radiation time were examined.

  7. Calcified-tissue investigations using synchrotron x-ray microscopy

    SciTech Connect

    Jones, K.W.; Spanne, P.; Schidlovsky, G.; Dejun, X. ); Bockman, R.S. . Medical Coll.); Rabinowitz, M.B. ); Hammond, P.B.; Bornschein, R.L. ); Hoeltzel, D.A. )

    1990-10-01

    Synchrotron x-ray microscopy (SXRM) in both emission and absorption modes has been used to examine elemental distributions in specimens of rat tibia, human deciduous teeth, and an orthopedic implant phantom. The work was performed with a spatial resolution of 8 {mu}m for the emission work and 25 {mu}m for the absorption work. The results illustrate the usefulness of SXRM for measurements of different types of calcified tissue. 3 figs.

  8. Soft X-Ray Emissions from Planets and Moons

    NASA Technical Reports Server (NTRS)

    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)

    2002-01-01

    The soft x-ray energy band (less than 4 keV) is an important spectral regime for planetary 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 x-ray emissions from their auroral (polar) regions, thus providing vital information on the nature of precipitating particles and their energization processes in planetary magnetospheres. X rays from low latitudes have also been observed on these planets, resulting largely from atmospheric scattering and fluorescence of solar x-rays. Cometary x-rays are now a well established phenomena, more than a dozen comets have been observed at soft x-ray energies, with the accepted production mechanism being charge-exchange between heavy solar wind ions and cometary neutrals. Also, Lunar x-rays have been observed and are thought to be produced by scattering and fluorescence of solar x-rays from the Moon's surface. With the advent of sophisticated x-ray observatories, e.g., Chandra and XMM-Newton, the field of planetary x-ray astronomy is advancing at a much faster pace. The Chandra X-ray Observatory (CXO) has recently captured soft x-rays from Venus. Venusian x-rays are most likely produced through fluorescence of solar x-rays by C and O atoms in the upper atmosphere. Very recently, using CXO we have discovered soft x-rays from the moons of Jupiter-Io, Europa, and probably Ganymede. The plausible source of the x-rays 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 x-rays by CXO have revealed a mysterious pulsating (period approx. 45 minutes) x-ray hot spot is fixed in magnetic latitude and longitude and is magnetically connected to a region in the outer magnetosphere of Jupiter. These

  9. The Origin of Soft X-rays in DQ Herculis

    NASA Technical Reports Server (NTRS)

    White, Nicholas E. (Technical Monitor); Mukai, K.; Still, M.; Ringwald, F. A.

    2002-01-01

    DQ Herculis (Nova Herculis 1934) is a deeply eclipsing cataclysmic variable containing a magnetic white dwarf primary. The accretion disk is thought to block our line of sight to the white dwarf at all orbital phases due to its extreme inclination angle. Nevertheless, soft X-rays were detected from DQ Her with ROSAT PSPC. To probe the origin of these soft X-rays, we have performed Chandra ACIS observations. We confirm that DQ Her is an X-ray source. The bulk of the X-rays are from a point-like source and exhibit a shallow partial eclipse. We interpret this as due to scattering of the unseen central X-ray source, probably in an accretion disk wind. At the same time, we detect weak extended X-ray features around DQ Her, which we interpret as an X-ray emitting knot in the nova shell.

  10. The hard X-ray perspective on the soft X-ray excess

    SciTech Connect

    Vasudevan, Ranjan V.; Mushotzky, Richard F.; Reynolds, Christopher S.; Lohfink, Anne M.; Zoghbi, Abderahmen; Fabian, Andrew C.; Gallo, Luigi C.; Walton, Dominic

    2014-04-10

    The X-ray spectra of many active galactic nuclei exhibit a 'soft excess' below 1 keV, whose physical origin remains unclear. Diverse models have been suggested to account for it, including ionized reflection of X-rays from the inner part of the accretion disk, ionized winds/absorbers, and Comptonization. The ionized reflection model suggests a natural link between the prominence of the soft excess and the Compton reflection hump strength above 10 keV, but it has not been clear what hard X-ray signatures, if any, are expected from the other soft X-ray candidate models. Additionally, it has not been possible up until recently to obtain high-quality simultaneous measurements of both soft and hard X-ray emission necessary to distinguish these models but upcoming joint XMM-NuSTAR programs provide precisely this opportunity. In this paper, we present an extensive analysis of simulations of XMM-NuSTAR observations, using two candidate soft excess models as inputs, to determine whether such campaigns can disambiguate between them by using hard and soft X-ray observations in tandem. The simulated spectra are fit with the simplest 'observer's model' of a blackbody and neutral reflection to characterize the strength of the soft and hard excesses. A plot of the strength of the hard excess against the soft excess strength provides a diagnostic plot which allows the soft excess production mechanism to be determined in individual sources and samples using current state-of-the-art and next generation hard X-ray enabled observatories. This approach can be straightforwardly extended to other candidate models for the soft excess.

  11. Applications of soft x-ray magnetic dichroism

    NASA Astrophysics Data System (ADS)

    van der Laan, G.

    2013-04-01

    Applications of x-ray magnetic circular and linear dichroism (XMCD and XMLD) are reviewed in the soft x-ray region, covering the photon energy range 0.4-2 keV, which includes important absorption edges such as the 3d transition metal L2,3 and rare earth M4,5. These techniques enable a broad range of novel and exciting studies such as on the electronic properties and magnetic ordering of novel nanostructured systems. XMCD has a sensitivity better than 0.01 monolayer (at the surface) and due to simple detection methods, such as electron yield and fluorescence yield, it has become a workhorse technique in physics and materials science. It is the only element-specific technique able to distinguish between the spin and orbital parts of the magnetic moments. The applications are vast, e.g., in x-ray holographic imaging, XMCD gives a spatial resolution of tens of nm. While many studies in the past were centered on physics, more recently new applications have emerged in areas such as chemistry, biology and earth and environmental sciences. For instance, XMCD allows the determination of the cation occupations in spinels and other ternary oxides. In scanning transmission x-ray microscopy (STXM), XMCD enables us to map biogenic magnetite redox changes resulting in a surprising degree of variation on the nanoscale. Another recent development is ferromagnetic resonance (FMR) detected by time-resolved XMCD which opens the door to element-, site- and layer-specific dynamical measurements. By exploiting the time structure of the pulsed synchrotron radiation from the storage ring the relative phase of precession in the individual magnetic layers of a multilayer stack can be determined.

  12. Burning DT Plasmas with Ultrafast Soft X-Ray Pulses

    NASA Astrophysics Data System (ADS)

    Hu, S. X.; Goncharov, V. N.; Skupsky, S.

    2012-10-01

    Fast ignition with narrowband, coherent ultrafast soft x-ray pulsesfootnotetextS. X. Hu, V. N. Goncharov, and S. Skupsky, ``Burning Plasmas with Ultrashort Soft-X-Ray 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 x-rays (hν = 3 to 6 keV) proposed in the original x-ray fast-ignition proposal, we find that soft x-ray 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 x-ray heating) with 50-μm-offset targets: an ˜10-ps soft x-ray 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 x-ray 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 x-ray 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 x-ray pulse at 1.65-kJ energy. Even though such energetic x-ray sources do not currently exist, we hope that the proposed ignition scheme may stimulate efforts on generating powerful soft x-ray sources in future. This work was supported by the U.S. Department of Energy Office of Inertial Confinement Fusion under Cooperative Agreement No. DE-FC52-08NA28302.

  13. The recent development of an X-ray grating interferometer at Shanghai Synchrotron Radiation Facility

    SciTech Connect

    Sun Haohua; Kou Bingquan; Xi Yan; Qi Juncheng; Sun Jianqi; Mohr, Juergen; Boerner, Martin; Zhao Jun; Xu, Lisa X.; Xiao Tiqiao; Wang Yujie

    2012-07-31

    An X-ray grating interferometer has been installed at Shanghai Synchrotron Radiation Facility (SSRF). Three sets of phase gratings were designed to cover the wide X-ray energy range needed for biological and soft material imaging capabilities. The performance of the grating interferometer has been evaluated by a tomography study of a PMMA particle packing and a new born mouse chest. In the mouse chest study, the carotid artery and carotid vein inside the mouse can be identified in situ without contrast agents.

  14. Research on x-ray optics with the ultimate aim of producing a synchrotron radiation pumped soft x-ray lithium laser. Progress report, January 1-October 1, 1985

    SciTech Connect

    Csonka, P.

    1986-02-28

    This report covers a 9.5 month period starting on January 1, 1985, and ending on October 14, 1985. During the reporting period, we have met our research goals as set forth in our original proposal. Our first task was to investigate a variety of focusing devices with the aim of generating at the focus a high flux of x-ray photons, per unit surface area, per unit time. Information is presented on the design, development, and specifications of the selected high performance ellipsoidal mirror. (JDB)

  15. Moon: lunar albedo for soft x-rays

    NASA Astrophysics Data System (ADS)

    Ibadov, Subhon

    2016-07-01

    Albedo of the Moon for soft X-rays (0.1-2 keV photons) is determined on the basis of the X-ray luminosity of the Moon detected and measured for the first time by orbital space telescope ROSAT in 1990. It is found that the lunar albedo for the solar soft X-rays is less than the lunar visual region albedo almost thousand times. The data allow to estimate more correctly X-ray luminosity of dusty comets like Hyakutake C/1996 B2 and Hale-Bopp C/1995 O1 due to scattering of solar soft X-rays and to reveal thus the dominant mechanism for production of X-rays in dusty comets.

  16. Time-resolved near-edge x-ray absorption fine structure spectroscopy on photo-induced phase transitions using a tabletop soft-x-ray spectrometer

    NASA Astrophysics Data System (ADS)

    Grossmann, P.; Rajkovic, I.; Moré, R.; Norpoth, J.; Techert, S.; Jooss, C.; Mann, Klaus

    2012-05-01

    We present a table-top soft-x-ray spectrometer for the wavelength range λ = 1-5 nm based on a stable laser-driven x-ray source, making use of a gas-puff target. With this setup, optical light-pump/soft-x-ray probe near-edge x-ray absorption fine structure (NEXAFS) experiments with a temporal resolution of about 230 ps are feasible. Pump-probe NEXAFS measurements were carried out in the "water-window" region (2.28 nm-4.36 nm) on the manganite Pr0.7Ca0.3MnO3, investigating diminutive changes of the oxygen K edge that derive from an optically induced phase transition. The results show the practicability of the table-top soft-x-ray spectrometer on demanding investigations so far exclusively conducted at synchrotron radiation sources.

  17. Time-resolved near-edge x-ray absorption fine structure spectroscopy on photo-induced phase transitions using a tabletop soft-x-ray spectrometer.

    PubMed

    Grossmann, P; Rajkovic, I; Moré, R; Norpoth, J; Techert, S; Jooss, C; Mann, Klaus

    2012-05-01

    We present a table-top soft-x-ray spectrometer for the wavelength range λ = 1-5 nm based on a stable laser-driven x-ray source, making use of a gas-puff target. With this setup, optical light-pump/soft-x-ray probe near-edge x-ray absorption fine structure (NEXAFS) experiments with a temporal resolution of about 230 ps are feasible. Pump-probe NEXAFS measurements were carried out in the "water-window" region (2.28 nm-4.36 nm) on the manganite Pr(0.7)Ca(0.3)MnO(3), investigating diminutive changes of the oxygen K edge that derive from an optically induced phase transition. The results show the practicability of the table-top soft-x-ray spectrometer on demanding investigations so far exclusively conducted at synchrotron radiation sources.

  18. The use of undulator radiation in VUV and soft x-ray radiometry

    SciTech Connect

    Kincaid, B.M.

    1991-11-01

    A new generation of synchrotron radiation light sources covering the VUV, soft x-ray and hard x-ray and spectral regions is under construction in several countries, designed specifically to use periodic magnetic undulators and low-emittance electron or positron beams to produce high-brightness near-diffraction-limited synchrotron radiation beams. It should be possible to use specially designed undulators and wigglers in the new synchrotron light facilities as tunable narrow band radiometric sources in the VUV and soft x-ray regions. An introduction to the physics of undulator radiation is followed by a discussion of some of the consequences of maximizing source performance, including high beam power, harmonics, optics contamination, and the unusual spectral and angular properties of undulator radiation. The limitations of the presently planned undulators as radiometric sources and the design criteria for a possible radiometry undulator will be discussed.

  19. The Development of a Scanning Soft X-Ray Microscope.

    NASA Astrophysics Data System (ADS)

    Rarback, Harvey Miles

    We have developed a scanning soft X-ray microscope, which can be used to image natural biological specimens at high resolution and with less damage than electron microscopy. The microscope focuses a monochromatic beam of synchrotron radiation to a nearly diffraction limited spot with the aid of a high resolution Fresnel zone plate, specially fabricated for us at the IBM Watson Research Center. The specimen at one atmosphere is mechanically scanned through the spot and the transmitted radiation is efficiently detected with a flow proportional counter. A computer forms a realtime transmission image of the specimen which is displayed on a color monitor. Our first generation optics have produced images of natural wet specimens at a resolution of 300 nm.

  20. Soft X-rays from the Cygnus Loop: Interpretation.

    PubMed

    Tucker, W H

    1971-04-23

    Two possible interpretations of the recent soft x-ray observation of the Cygnus Loop are discussed. A synchrotron model requires a magnetic field less than 10(-6) gauss and electron energies in excess of 10(14) electron volts. These electrons must either have been reaccelerated or continuously injected into the source for about 50,000 years. The observations are also consistent with the radiation from a hot plasma having the cosmic abundances of the elements. A likely origin for the hot plasma is a blast wave produced by the explosion of a supernova in the interstellar medium. Fitting such a model to the observations implies a kinetic energy release in the explosion of 6x 10(50) ergs for an assumed distance of 770 parsec.

  1. Diffractometer for soft x-ray resonant magnetic scattering

    NASA Astrophysics Data System (ADS)

    Grabis, J.; Nefedov, A.; Zabel, H.

    2003-09-01

    We report on the design and construction of a new diffractometer for soft x-ray resonant magnetic scattering which has been built at the Ruhr-University Bochum. The ultrahigh vacuum-compatible diffractometer comprises a two-circle goniometer and works in horizontal scattering geometry. Rotation of the detector and sample is realized by two differentially pumped rotating platforms with motors and gears external to the vacuum. The sample environment consists of a closed-cycle He cryostat that allows heating up to 600 K and applying a magnetic field of ±2.5 kOe. All functions of the experimental setup have been extensively tested at the BESSY II Synchrotron (beamline PM3). The experimental results demonstrate the performance of the instrument.

  2. Applications of synchrotron X-rays to radiotherapy

    NASA Astrophysics Data System (ADS)

    Blattmann, H.; Gebbers, J.-O.; Bräuer-Krisch, E.; Bravin, A.; Le Duc, G.; Burkard, W.; Di Michiel, M.; Djonov, V.; Slatkin, D. N.; Stepanek, J.; Laissue, J. A.

    2005-08-01

    Radiotherapy is among the most useful treatments of cancer. Penetrating radiation (ionizing particles or bremsstrahlung photons) is aimed toward the tumor-bearing target, gradually delivering as high radiation to it as is usefully suppressive of tumor growth, yet tolerated by normal vital tissues inevitably irradiated with the tumor. The high collimation and dose rate of synchrotron X-ray beams, even when monochromatized, favor radiotherapy. Photon activation therapy, tomotherapy, microbeam radiation therapy, and radiosurgery mediated by synchrotron wigglers are conceptually promising for difficult tumors. Radiotherapy of malignant brain tumors in rats has been encouraging, but suitable beam lines exist at only a few research facilities and much basic work must be done before the promise of synchrotron-based radiotherapy can be realized clinically.

  3. Observation of soft X-rays from cosmic sources

    NASA Technical Reports Server (NTRS)

    Catura, R. C.; Acton, L. W.

    1975-01-01

    A binary X-ray source, an extended extragalactic X-ray source and several nearby stars were surveyed for X-ray emission. The energy spectrum and time structure of X-ray flux from the binary source, Her X-l, was investigated in the range from 0.15 to 6 KeV. This source was observed at a binary phase of 0.18 with the system near elongation normal to the line of sight. Intense pulsations were observed in optical emission lines near this binary phase. The spectrum and angular distribution of X-ray emission from the X-ray source in the Virgo Cluster of Galaxies, near M 87, was also observed. In addition, the stars Alpha Leo, Zeta Her, and Epsilon Vir were investigated. Epsilon Aur and Alpha Aur were also scanned. These stars were studied since there is increasing evidence that such objects may be transient sources of soft X-rays.

  4. Miniature pulsed magnet system for synchrotron x-ray measurements

    SciTech Connect

    Linden, Peter J. E. M. van der; Mathon, Olivier; Strohm, Cornelius; Sikora, Marcin

    2008-07-15

    We have developed a versatile experimental apparatus for synchrotron x-ray measurements in pulsed high magnetic fields. The apparatus consists of a double cryostat incorporating a liquid nitrogen bath to cool the miniature pulsed coil and an independent helium flow cryostat allowing sample temperatures from 4 up to 250 K. The high duty cycle miniature pulsed coils can generate up to 38 T. During experiments at 30 T a repetition rate of 6 pulses/min was routinely reached. Using a 4 kJ power supply, the pulse duration was between 500 {mu}s and 1 ms. The setup was used for nuclear forward scattering measurements on {sup 57}Fe up to 25 T on the ESRF beamline ID18. In another experiment, x-ray magnetic circular dichroism was measured up to 30 T on the ESRF energy dispersive beamline ID24.

  5. Miniature pulsed magnet system for synchrotron x-ray measurements.

    PubMed

    van der Linden, Peter J E M; Mathon, Olivier; Strohm, Cornelius; Sikora, Marcin

    2008-07-01

    We have developed a versatile experimental apparatus for synchrotron x-ray measurements in pulsed high magnetic fields. The apparatus consists of a double cryostat incorporating a liquid nitrogen bath to cool the miniature pulsed coil and an independent helium flow cryostat allowing sample temperatures from 4 up to 250 K. The high duty cycle miniature pulsed coils can generate up to 38 T. During experiments at 30 T a repetition rate of 6 pulsesmin was routinely reached. Using a 4 kJ power supply, the pulse duration was between 500 mus and 1 ms. The setup was used for nuclear forward scattering measurements on 57Fe up to 25 T on the ESRF beamline ID18. In another experiment, x-ray magnetic circular dichroism was measured up to 30 T on the ESRF energy dispersive beamline ID24.

  6. Synchrotron X-ray Microbeam Diffraction from Abalone Shell

    NASA Astrophysics Data System (ADS)

    Dimasi, Elaine; Sarikaya, Mehmet

    2004-03-01

    Microstructured biomaterials such as mollusk shells receive much attention, due to the promise that advanced materials can be designed and synthesized with biomimetic techniques that take advantage of self-assembly and aqueous, ambient processing conditions. A satisfactory understanding of this process requires characterization of the microstructure at the growth fronts where control over crystal orientation and morphology is enacted. We present synchrotron x-ray microbeam observations near the nacre-prismatic interface of red abalone shell (Haliotis rufescens). The relative orientations of calcite and aragonite grains exhibit differences from the idealizations reported previously. Long calcite grains impinge the boundary at 45^rc angles, suggestive of nucleation on (104) planes followed by c-axis growth. Within 100 μm of the boundary, crystals lose their bulk orientational order. The calcite crystal mosaic measured by x-ray diffraction rocking curves is resolution limited, comparable to geological calcite.

  7. Pulsars, X-ray synchrotron nebulae, and guest stars

    NASA Technical Reports Server (NTRS)

    Seward, Frederick D.; Wang, Zhen-Ru

    1988-01-01

    X-ray observations of supernova remnants and radio pulsars are used to derive luminosities of neutron stars and synchrotron nebulae. Observations of known isolated pulsars are used to develop an empirical relationship between the X-ray luminosity and the rate of loss of rotational energy. This is used to derive the characteristics of pulsars hidden in remnants which show evidence for a central compact object or associated nebular emission, but no clear pulsed signal from the neutron star itself. Possible periods and period derivatives for the hidden pulsars are discussed. Some might have periods as long as 0.5 s, and period derivatives considerably higher than that of PSR 1509 - 58, currently the pulsar with the highest known period derivative.

  8. Pulsars, X-ray synchrotron nebulae, and guest stars

    NASA Technical Reports Server (NTRS)

    Seward, Frederick D.; Wang, Zhen-Ru

    1988-01-01

    X-ray observations of supernova remnants and radio pulsars are used to derive luminosities of neutron stars and synchrotron nebulae. Observations of known isolated pulsars are used to develop an empirical relationship between the X-ray luminosity and the rate of loss of rotational energy. This is used to derive the characteristics of pulsars hidden in remnants which show evidence for a central compact object or associated nebular emission, but no clear pulsed signal from the neutron star itself. Possible periods and period derivatives for the hidden pulsars are discussed. Some might have periods as long as 0.5 s, and period derivatives considerably higher than that of PSR 1509 - 58, currently the pulsar with the highest known period derivative.

  9. Hard X-Ray, Soft X-Ray, and EUV Studies of Solar Eruptions

    NASA Technical Reports Server (NTRS)

    Sterling, Alphonse C.; Wagner, William (Technical Monitor)

    2003-01-01

    Document study the hard X-ray (HXR), soft X-ray (SXR) ,EUV, and magnetic nature of solar eruptions, with the objective of elucidating the physics of the eruption process. In particular, it was examine the viability of two specific eruption mechanisms, detailed in our proposal. These mechanisms are the "breakout model", and the "tether cutting model". During the second year, it was a significant progress in the goals to Data Sets Utilized. In the publications during this second year of the grant period, the data was used from the E W Imaging Telescope (EIT) and the Michelson Doppler Imager (MDI) instruments on SOHO, and from the Soft X-ray Telescope (SXT), Hard X-ray Telescope (HXT), and the Bragg Crystal Spectrometer (BCS) on Yooh.

  10. Soft x-ray excited optical luminescence from poly(N-vinylcarbazole)

    NASA Astrophysics Data System (ADS)

    Naftel, S. J.; Kim, P.-S. G.; Sham, T. K.; Sammynaiken, R.; Yates, B. W.; Hu, Y.-F.

    2003-05-01

    X-ray excited optical luminescence (XEOL) using tunable soft x rays from a synchrotron light source, together with x-ray absorption fine structure spectroscopy has been used to study the electronic structure and optical properties of thin films of poly(N-vinylcarbazole). It is found that carbon core level excitation enhances the formation of excimers emitting at 380 and 410 nm. A third excimer at 310 nm is also noted. In addition, excitations across the C K edge and the N K edge show noticeably different optical response. These results are interpreted in terms of the site specificity of the XEOL technique.

  11. Burning plasmas with ultrashort soft-x-ray flashing

    NASA Astrophysics Data System (ADS)

    Hu, S. X.; Goncharov, V. N.; Skupsky, S.

    2012-07-01

    Fast ignition with narrow-band coherent x-ray pulses has been revisited for cryogenic deuterium-tritium (DT) plasma conditions achieved on the OMEGA Laser System. In contrast to using hard-x-rays (hv = 3-6 keV) proposed in the original x-ray fast-ignition proposal, we find that soft-x-ray 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-x-ray heating) with 50-μm-offset targets: ˜10 ps soft-x-ray pulse (hv ≈ 500 eV) with a total energy of 500-1000 J to be focused into a 10 μm spot-size. A variety of x-ray 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 x-ray 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-x-ray pulse at 1.65 kJ energy. Even though such energetic x-ray sources do not currently exist, we hope that the proposed ignition scheme may stimulate efforts on generating powerful soft-x-ray sources in the near future.

  12. Burning plasmas with ultrashort soft-x-ray flashing

    SciTech Connect

    Hu, S. X.; Goncharov, V. N.; Skupsky, S.

    2012-07-15

    Fast ignition with narrow-band coherent x-ray pulses has been revisited for cryogenic deuterium-tritium (DT) plasma conditions achieved on the OMEGA Laser System. In contrast to using hard-x-rays (hv = 3-6 keV) proposed in the original x-ray fast-ignition proposal, we find that soft-x-ray 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-x-ray heating) with 50-{mu}m-offset targets: {approx}10 ps soft-x-ray 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 x-ray 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 x-ray 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-x-ray pulse at 1.65 kJ energy. Even though such energetic x-ray sources do not currently exist, we hope that the proposed ignition scheme may stimulate efforts on generating powerful soft-x-ray sources in the near future.

  13. Development of small scale soft x-ray lasers

    SciTech Connect

    Kim, D.; Suckewer, S. . Plasma Physics Lab. Princeton Univ., NJ . Dept. of Mechanical and Aerospace Engineering); Skinner, C.H.; Voorhees, D. . Plasma Physics Lab.)

    1991-05-01

    At present rapid progress is being made in the application of soft x-ray lasers to fields such as microscopy and microlithography. A critical factor in the range of suitable applications is the scale and hence cost of the soft x-ray lasers. At Princeton, gain at 183{angstrom} has been obtained with relatively low pump laser energies (as low as 6J) in a portable'' small-scale soft x-ray laser system. We will also discuss aspects of data interpretation and pitfalls to be avoided in measurements of gain in such systems. 14 refs., 7 figs.

  14. Soft X-Ray Observations of a Complete Sample of X-Ray--selected BL Lacertae Objects

    NASA Astrophysics Data System (ADS)

    Perlman, Eric S.; Stocke, John T.; Wang, Q. Daniel; Morris, Simon L.

    1996-01-01

    We present the results of ROSAT PSPC observations of the X-ray selected BL Lacertae objects (XBLs) in the complete Einstein Extended Medium Sensitivity Survey (EM MS) sample. None of the objects is resolved in their respective PSPC images, but all are easily detected. All BL Lac objects in this sample are well-fitted by single power laws. Their X-ray spectra exhibit a variety of spectral slopes, with best-fit energy power-law spectral indices between α = 0.5-2.3. The PSPC spectra of this sample are slightly steeper than those typical of flat ratio-spectrum quasars. Because almost all of the individual PSPC spectral indices are equal to or slightly steeper than the overall optical to X-ray spectral indices for these same objects, we infer that BL Lac soft X-ray continua are dominated by steep-spectrum synchrotron radiation from a broad X-ray jet, rather than flat-spectrum inverse Compton radiation linked to the narrower radio/millimeter jet. The softness of the X-ray spectra of these XBLs revives the possibility proposed by Guilbert, Fabian, & McCray (1983) that BL Lac objects are lineless because the circumnuclear gas cannot be heated sufficiently to permit two stable gas phases, the cooler of which would comprise the broad emission-line clouds. Because unified schemes predict that hard self-Compton radiation is beamed only into a small solid angle in BL Lac objects, the steep-spectrum synchrotron tail controls the temperature of the circumnuclear gas at r ≤ 1018 cm and prevents broad-line cloud formation. We use these new ROSAT data to recalculate the X-ray luminosity function and cosmological evolution of the complete EMSS sample by determining accurate K-corrections for the sample and estimating the effects of variability and the possibility of incompleteness in the sample. Our analysis confirms that XBLs are evolving "negatively," opposite in sense to quasars, with Ve/Va = 0.331±0.060. The statistically significant difference between the values for

  15. Novel approaches for correction against the soft matrix effects in the quantitative elemental imaging of human substantia nigra tissue using synchrotron X-ray fluorescence

    NASA Astrophysics Data System (ADS)

    Surowka, A. D.; Wrobel, P.; Marzec, M. M.; Adamek, D.; Szczerbowska-Boruchowska, M.

    2016-09-01

    The inherent structural heterogeneity of biological specimens poses a number of problems for analytical techniques to assess for the elemental composition of a sample, and this is the case with quantitative X-ray fluorescence (XRF). Differences in density along with any possible variation in thickness upon frequently used freeze drying of thin samples could influence the results of the quantification and therefore underlie one of the most critical matrix effects in XRF, often referred to as the mass thickness effect. In our study, we analyzed substantia nigra tissue samples of various thicknesses mounted onto silicon nitride membranes. The aim was to show up the variation in the mass thickness of the different substantia nigra tissue compartments: the neuromelanine pigmented neurons and neuropil could influence the final quantitative results. In that respect, the main goal was to derive several semi- and fully-quantitative methods to correct for the mass thickness effects using either a membrane Si transmission signal or the intensity of incoherently scattered primary X-ray radiation. Also, the pioneer topographic studies on dried substantia nigra tissue specimens demonstrated the drying procedure is accompanied by an around 80% reduction in the samples' thickness. The correction scheme is presented together with the semi-theoretical procedure developed to compute for the mass thickness for substantia nigra tissue structures, and the correction scheme's robustness is also presented.

  16. First Terrestrial Soft X-ray Auroral Observation by the Chandra X-Ray Observatory

    NASA Technical Reports Server (NTRS)

    Bhardwaj, Anil; Elsner, Ronald F.; Gladstone, G. Randall; Ostegaard, Nikolai; Waite, J. Hunter, Jr.; Cravens, Thomas E.; Chang, Shen-Wu; Majeed, Tariq; Metzger, Albert E.

    2004-01-01

    Northern auroral regions of Earth were imaged using the High-Resolution Camera (HRC-1) aboard the Chandra X-Ray Observatory (CXO) at 10 epochs (each approx.20 min duration) between mid-December 2003 and mid-April 2004. These observations aimed at searching for Earth s soft (<2 keV) x-ray aurora in a comparative study with Jupiter s x-ray aurora, where a pulsating x-ray "hot-spot" has been previously observed by Chandra. The first Chandra soft x-ray observations of Earth s aurora show that it is highly variable (intense arcs, multiple arcs, diffuse patches, at times absent). In at least one of the observations an isolated blob of emission is observed near the expected cusp location. A fortuitous overflight of DMSP satellite F13 provided SSJ/4 energetic particle measurements above a bright arc seen by Chandra on 24 January 2004, 20:01-20:22 UT. A model of the emissions expected strongly suggests that the observed soft x-ray signal is produced by electron bremsstrahlung.

  17. First Terrestrial Soft X-Ray Auroral Observation by the Chandra X-Ray Observatory

    NASA Technical Reports Server (NTRS)

    Bhardwaj, Anil; Gladstone, G. Randall; Elsner, Ronald F.; Oestgaard, Nikolai; Waite, J. Hunter, Jr.; Cravens, Thomas E.; Chang, Shen-Wu; Majeed, Tariq; Metzger, Albert E.

    2007-01-01

    Northern auroral regions of Earth were imaged with energetic photons in the 0.1-10keV range using the High-Resolution Camera (HRC-I) aboard the Chandra X-ray Observatory at 10 epochs (each approx.20 min duration) between mid- December 2003 and mid-April 2004. These observations aimed at searching for Earth's soft (< 2 keV) X-ray aurora in a comparative study with Jupiter's X-ray aurora, where a pulsating X-ray "hot-spot" has been previously observed by Chandra. The first Chandra soft X-ray observations of Earth's aurora show that it is highly variable 0ntense arcs, multiple arcs, diffuse patches, at times absent). In at least one of the observations an isolated blob of emission is observed near the expected cusp location. A fortuitous overflight of DMSP satellite F13 provided SSJ/4 energetic particle measurements above a bright arc seen by Chandra on 24 January 2004, 20:01-20:22 UT. A model of the emissions expected strongly suggests that the observed soft X-ray signal is bremsstrahlung and characteristic K-shell line emissions of nitrogen and oxygen in the atmosphere produced by electrons.

  18. Energy Dependence of Synchrotron X-Ray Rims in Tycho's Supernova Remnant

    NASA Technical Reports Server (NTRS)

    Tran, Aaron; Williams, Brian J.; Petre, Robert; Ressler, Sean M.; Reynolds, Stephen P.

    2015-01-01

    Several young supernova remnants exhibit thin X-ray bright rims of synchrotron radiation at their forward shocks. Thin rims require strong magnetic field amplification beyond simple shock compression if rim widths are only limited by electron energy losses. But, magnetic field damping behind the shock could produce similarly thin rims with less extreme field amplification. Variation of rim width with energy may thus discriminate between competing influences on rim widths. We measured rim widths around Tycho's supernova remnant in 5 energy bands using an archival 750 ks Chandra observation. Rims narrow with increasing energy and are well described by either loss-limited or damped scenarios, so X-ray rim width-energy dependence does not uniquely specify a model. But, radio counterparts to thin rims are not loss-limited and better reflect magnetic field structure. Joint radio and X-ray modeling favors magnetic damping in Tycho's SNR with damping lengths approximately 1-5% of remnant radius and magnetic field strengths approximately 50-400 micron G assuming Bohm diffusion. X-ray rim widths are approximately 1% of remnant radius, somewhat smaller than inferred damping lengths. Electron energy losses are important in all models of X-ray rims, suggesting that the distinction between loss-limited and damped models is blurred in soft X-rays. All loss-limited and damping models require magnetic fields approximately greater than 20 micron G, arming the necessity of magnetic field amplification beyond simple compression.

  19. ENERGY DEPENDENCE OF SYNCHROTRON X-RAY RIMS IN TYCHO’S SUPERNOVA REMNANT

    SciTech Connect

    Tran, Aaron; Williams, Brian J.; Petre, Robert; Reynolds, Stephen P.

    2015-10-20

    Several young supernova remnants (SNRs) exhibit thin X-ray bright rims of synchrotron radiation at their forward shocks. Thin rims require strong magnetic field amplification beyond simple shock compression if rim widths are only limited by electron energy losses. But, magnetic field damping behind the shock could produce similarly thin rims with less extreme field amplification. Variation of rim width with energy may thus discriminate between competing influences on rim widths. We measured rim widths around Tycho's SNR in five energy bands using an archival 750 ks Chandra observation. Rims narrow with increasing energy and are well described by either loss-limited or damped scenarios, so X-ray rim width-energy dependence does not uniquely specify a model. But, radio counterparts to thin rims are not loss-limited and better reflect magnetic field structure. Joint radio and X-ray modeling favors magnetic damping in Tycho's SNR with damping lengths ∼1%–5% of remnant radius and magnetic field strengths ∼50–400 μG assuming Bohm diffusion. X-ray rim widths are ∼1% of remnant radius, somewhat smaller than inferred damping lengths. Electron energy losses are important in all models of X-ray rims, suggesting that the distinction between loss-limited and damped models is blurred in soft X-rays. All loss-limited and damping models require magnetic fields ≳20 μG, affirming the necessity of magnetic field amplification beyond simple compression.

  20. Synchrotron x-ray studies of Austenite and Bainitic ferrite

    SciTech Connect

    Stone, H.; Peet, M.; Bhadeshia, H. K. D. H.; Withers, P.; Babu, Sudarsanam S; Specht, Eliot D

    2008-01-01

    High resolution synchrotron X-ray diffraction has been used to conduct in situ studies of the temporal evolution of phases during the isothermal growth of bainite. Two populations of austenitic material were identified: one corresponding to the initial austenite, the other to the carbon-enriched austenite associated with the bainitic ferrite. The observed lattice parameters and the asymmetry of the peaks from the residual austenite have been interpreted in terms of the carbon partitioning during the transformation. The results are contrasted with an earlier study in which the austenite unit cell appeared to split into two distinct densities prior to the onset of transformation.

  1. Synchrotron Radiation and X-ray FEL Projects in Korea

    NASA Astrophysics Data System (ADS)

    Cho, M. H.

    2012-03-01

    There are two on-going major projects in Pohang Accelerator Laboratory (PAL), the PLS-II light source upgrade and the construction of PAL-XFEL facility. PLS-II is a new light source upgraded from PLS(Pohang Light Source) which had been operated for 16 years from 1995 and shut down in Dec. 2010. The performance will be improved from ``18.9 nm-rad, 2.5 GeV, and 200 mA'' to ``5.8 nm-rad, 3 GeV, and 400 mA'' using three superconducting RF cavities. The old storage ring has been completely dismantled and new DBA ring has been re-installed in the same tunnel within 6 months, and is under commissioning now. The unique feature of PLS-II is the compact employment of 20 insertion-devices including 14 in-vacuum undulators. The PALXFEL is a 0.1-nm hard X-ray FEL construction project started in 2011 and to compete in 2014 with a total budget of 400 M. The PAL-XFEL is designed to have hard X-ray undulator lines at the end of 10-GeV linac, and a dog-leg branch line at 2.65 GeV point for a soft X-ray undulator line simultaneously and independently from hard X-ray FEL undulator line. The overview of two projects with current status is presented.

  2. Soft x-ray holographic microscopy

    SciTech Connect

    Stickler, Daniel; Froemter, Robert; Stillrich, Holger; Menk, Christian; Oepen, Hans Peter; Tieg, Carsten; Streit-Nierobisch, Simone; Sprung, Michael; Gutt, Christian; Stadler, Lorenz-M.; Leupold, Olaf; Gruebel, Gerhard

    2010-01-25

    We present a new x-ray microscopy technique based on Fourier transform holography (FTH), where the sample is separate from the optics part of the setup. The sample can be shifted with respect to the holography optics, thus large-scale or randomly distributed objects become accessible. As this extends FTH into a true microscopy technique, we call it x-ray holographic microscopy (XHM). FTH allows nanoscale imaging without the need for nanometer-size beams. Simple Fourier transform yields an unambiguous image reconstruction. We demonstrate XHM by studying the magnetic domain evolution of a Co/Pt multilayer film as function of locally varied iron overlayer thickness.

  3. A high-intensity highly coherent soft X-ray femtosecond laser seeded by a high harmonic beam.

    PubMed

    Zeitoun, Ph; Faivre, G; Sebban, S; Mocek, T; Hallou, A; Fajardo, M; Aubert, D; Balcou, Ph; Burgy, F; Douillet, D; Kazamias, S; De Lachèze-Murel, G; Lefrou, T; Le Pape, S; Mercère, P; Merdji, H; Morlens, A S; Rousseau, J P; Valentin, C

    2004-09-23

    Synchrotrons have for decades provided invaluable sources of soft X-rays, the application of which has led to significant progress in many areas of science and technology. But future applications of soft X-rays--in structural biology, for example--anticipate the need for pulses with much shorter duration (femtoseconds) and much higher energy (millijoules) than those delivered by synchrotrons. Soft X-ray free-electron lasers should fulfil these requirements but will be limited in number; the pressure on beamtime is therefore likely to be considerable. Laser-driven soft X-ray sources offer a comparatively inexpensive and widely available alternative, but have encountered practical bottlenecks in the quest for high intensities. Here we establish and characterize a soft X-ray laser chain that shows how these bottlenecks can in principle be overcome. By combining the high optical quality available from high-harmonic laser sources (as a seed beam) with a highly energetic soft X-ray laser plasma amplifier, we produce a tabletop soft X-ray femtosecond laser operating at 10 Hz and exhibiting full saturation, high energy, high coherence and full polarization. This technique should be readily applicable on all existing laser-driven soft X-ray facilities.

  4. Soft x-ray reduction camera for submicron lithography

    DOEpatents

    Hawryluk, A.M.; Seppala, L.G.

    1991-03-26

    Soft x-ray projection lithography can be performed using x-ray optical components and spherical imaging lenses (mirrors), which form an x-ray reduction camera. The x-ray reduction is capable of projecting a 5x demagnified image of a mask onto a resist coated wafer using 4.5 nm radiation. The diffraction limited resolution of this design is about 135 nm with a depth of field of about 2.8 microns and a field of view of 0.2 cm[sup 2]. X-ray reflecting masks (patterned x-ray multilayer mirrors) which are fabricated on thick substrates and can be made relatively distortion free are used, with a laser produced plasma for the source. Higher resolution and/or larger areas are possible by varying the optic figures of the components and source characteristics. 9 figures.

  5. Soft x-ray reduction camera for submicron lithography

    DOEpatents

    Hawryluk, Andrew M.; Seppala, Lynn G.

    1991-01-01

    Soft x-ray projection lithography can be performed using x-ray optical components and spherical imaging lenses (mirrors), which form an x-ray reduction camera. The x-ray reduction is capable of projecting a 5x demagnified image of a mask onto a resist coated wafer using 4.5 nm radiation. The diffraction limited resolution of this design is about 135 nm with a depth of field of about 2.8 microns and a field of view of 0.2 cm.sup.2. X-ray reflecting masks (patterned x-ray multilayer mirrors) which are fabricated on thick substrates and can be made relatively distortion free are used, with a laser produced plasma for the source. Higher resolution and/or larger areas are possible by varying the optic figures of the components and source characteristics.

  6. Temperature dependent soft x-ray absorption spectroscopy of liquids

    NASA Astrophysics Data System (ADS)

    Meibohm, Jan; Schreck, Simon; Wernet, Philippe

    2014-10-01

    A novel sample holder is introduced which allows for temperature dependent soft x-ray absorption spectroscopy of liquids in transmission mode. The setup is based on sample cells with x-ray transmissive silicon nitride windows. A cooling circuit allows for temperature regulation of the sample liquid between -10 °C and +50 °C. The setup enables to record soft x-ray absorption spectra of liquids in transmission mode with a temperature resolution of 0.5 K and better. Reliability and reproducibility of the spectra are demonstrated by investigating the characteristic temperature-induced changes in the oxygen K-edge x-ray absorption spectrum of liquid water. These are compared to the corresponding changes in the oxygen K-edge spectra from x-ray Raman scattering.

  7. Temperature dependent soft x-ray absorption spectroscopy of liquids.

    PubMed

    Meibohm, Jan; Schreck, Simon; Wernet, Philippe

    2014-10-01

    A novel sample holder is introduced which allows for temperature dependent soft x-ray absorption spectroscopy of liquids in transmission mode. The setup is based on sample cells with x-ray transmissive silicon nitride windows. A cooling circuit allows for temperature regulation of the sample liquid between -10 °C and +50 °C. The setup enables to record soft x-ray absorption spectra of liquids in transmission mode with a temperature resolution of 0.5 K and better. Reliability and reproducibility of the spectra are demonstrated by investigating the characteristic temperature-induced changes in the oxygen K-edge x-ray absorption spectrum of liquid water. These are compared to the corresponding changes in the oxygen K-edge spectra from x-ray Raman scattering.

  8. Soft X-Ray Emissions from Planets and Moons

    NASA Technical Reports Server (NTRS)

    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)

    2002-01-01

    A wide variety of solar system planetary bodies are now known to radiate in the soft x-ray energy (<5 keV) regime. These include planets (Earth, Jupiter, Venus, Saturn): bodies having thick atmosphere and with/without intrinsic magnetic field; planetary 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 x-rays from these objects. whereas in the hard x-ray energy range (>10 keV) x-rays mainly result from electron bremsstrahlung process. In this paper we present a brief review of the x-ray observations on each of the planetary bodies and discuss their characteristics and proposed source mechanisms.

  9. Resonant soft X-ray scattering on protein solutions

    NASA Astrophysics Data System (ADS)

    Ye, Dan; Le, Thinh; Wang, Cheng; Zwart, Peter; Gomez, Esther; Gomez, Enrique

    Protein structure is crucial for biological function, such that characterizing protein folding and packing is important for the design of therapeutics and enzymes. We propose resonant soft X-ray scattering (RSOXS) as an approach to study proteins and other biological assemblies in solution. Calculations of the scattering contrast suggest that soft X-ray scattering is more sensitive than hard X-ray scattering, because of contrast generated at the absorption edges of constituent elements such as carbon, nitrogen and oxygen. We have examined the structure of bovine serum albumin (BSA) in solution by RSOXS. We find that by varying incident X-ray energies, we are able to achieve higher scattering contrast near the absorption edge. From our RSOXS scattering result we are able to reconstruct the structure of BSA in 3D. These RSOXS results also agree with hard X-ray experiments, including crystallographic data. Our study demonstrates the potential of RSOXS for studying protein structure in solution.

  10. Observations of X-ray jets with the Yohkoh Soft X-ray Telescope

    NASA Technical Reports Server (NTRS)

    Shibata, Kazunari; Ishido, Yoshinori; Acton, Loren W.; Strong, Keith T.; Hirayama, Tadashi; Uchida, Yutaka; Mcallister, Alan H.; Matsumoto, Ryoji; Tsuneta, Saku; Shimizu, Toshifumi

    1992-01-01

    The features of the multiple X-ray jets in the solar corona, revealed by the time series of the Yohkoh Soft X-ray Telescope images are described. The typical size of a jet was from 5 x 10 exp 3 to 4 x 10 exp 5 km, the translational velocity was 30-300 km/s, and the corresponding kinetic energy was estimated to be from 10 exp 25 to 10 exp 28 erg. Many of the jets were found to be associated with flares in X-ray bright points, emerging flux regions, or active regions, and they sometimes occurred several times from the same X-ray feature. One of the jets associated with a flaring bright point was identified as being an H-alpha surge.

  11. Bond cleavages of adenosine 5'-triphosphate induced by monochromatic soft X-rays

    NASA Astrophysics Data System (ADS)

    Fujii, K.; Narita, A.; Yokoya, A.

    2014-04-01

    To investigate which type of bond is likely to be cleaved by soft X-ray exposure to an adenosine 5'-triphosphate (ATP), we observed spectral changes in X-ray absorption near edge structure (XANES) around nitrogen and oxygen K-edge of an ATP film by soft X-ray irradiation. Experiments were performed at a synchrotron soft X-ray beamline at SPring-8, Japan. The XANES spectra around the nitrogen and oxygen .K-edge slightly varied by exposure to 560 eV soft X-rays. These changes are originated from the cleavage of C-N bonds between a sugar and a nucleobase site and of C-O, P-O or O-H bond of sugar and phosphate site. From the comparison between the change in XANES intensity of σ* peak at nitrogen and that at oxygen K-edges, it is inferred that the C-O, P-O or O-H bond of sugar and phosphate is much efficiently cleaved than the C-N of N-glycoside bond by the exposure of 560 eV soft X-ray to ATP film.

  12. Transition radiation as a coherent soft X-ray source

    NASA Astrophysics Data System (ADS)

    Moran, M. A.; Dahling, B. A.; Piestrup, M. A.; Berman, B. L.; Kephart, J. O.

    A series of experiments performed at the LLNL using 54-MeV electrons to irradiate thin-foil targets has demonstrated the spatially coherent nature of soft X-ray transition radiation. Results of measurements and calculations demonstrate both the intrafoil and interfoil coherence of transition radiation in multiple-foil targets. It is noted that coherent behavior results in distinctive angular distributions that are accurately predicted by theoretical calculations. Possible applications of the present work are the investigation of the X-ray optical constants of thin foils and the development of a spatially coherent tunable soft X-ray laser.

  13. Nuclear Transitions Induced by Synchrotron X-rays

    NASA Astrophysics Data System (ADS)

    Gemmell, Donald S.

    2003-01-01

    We discuss two rare but interesting processes by which synchrotron x-rays with energies up to about 100 keV may be used to induce nuclear transitions. In the NEET (Nuclear Excitation by Electronic Transition) process, an intense x-ray beam is employed to make vacancies, e.g. K-holes, in the atoms of a specific nuclear isotope. When a vacancy is filled by an electronic transition from a higher atomic level, there is some probability that instead of the usual x-ray or Auger emission, the nucleus of the atom itself will be excited. This is then followed by a nuclear decay exhibiting characteristic gamma-rays or other types of radiation, with time delays typical of the nuclear states involved. The probability for NEET increases when the energies of the atomic and the nuclear transitions become close. We address some theoretical aspects of the process and describe experimental efforts to observe it in 189Os and 197Au. The second process to be discussed is the possibility of "triggering" the decay of a nuclear isomer by irradiation with an x-ray beam. We focus on the case of the 31-year, 2.4-MeV, 16+ isomer of 178Hf. There has been speculation that if one could isolate gram quantities, say, of this isomer and then have the capability to accelerate its decay in a controlled way, one would have a powerful triggerable source of enormous energy. This could be used to generate explosions, for rapid irradiations, or for more general energy-storage applications, depending on the rate of energy release. We describe attempts to observe this process.

  14. Nuclear Transitions Induced by Synchrotron X-rays

    SciTech Connect

    Gemmell, Donald S.

    2003-01-24

    We discuss two rare but interesting processes by which synchrotron x-rays with energies up to about 100 keV may be used to induce nuclear transitions. In the NEET (Nuclear Excitation by Electronic Transition) process, an intense x-ray beam is employed to make vacancies, e.g. K-holes, in the atoms of a specific nuclear isotope. When a vacancy is filled by an electronic transition from a higher atomic level, there is some probability that instead of the usual x-ray or Auger emission, the nucleus of the atom itself will be excited. This is then followed by a nuclear decay exhibiting characteristic gamma-rays or other types of radiation, with time delays typical of the nuclear states involved. The probability for NEET increases when the energies of the atomic and the nuclear transitions become close. We address some theoretical aspects of the process and describe experimental efforts to observe it in 189Os and 197Au. The second process to be discussed is the possibility of 'triggering' the decay of a nuclear isomer by irradiation with an x-ray beam. We focus on the case of the 31-year, 2.4-MeV, 16+ isomer of 178Hf. There has been speculation that if one could isolate gram quantities, say, of this isomer and then have the capability to accelerate its decay in a controlled way, one would have a powerful triggerable source of enormous energy. This could be used to generate explosions, for rapid irradiations, or for more general energy-storage applications, depending on the rate of energy release. We describe attempts to observe this process.

  15. X-Ray Emission from the Soft X-Ray Transient Aquila X-1

    NASA Technical Reports Server (NTRS)

    Tavani, Marco

    1998-01-01

    Aquila X-1 is the most prolific of soft X-ray transients. It is believed to contain a rapidly spinning neutron star sporadically accreting near the Eddington limit from a low-mass companion star. The interest in studying the repeated X-ray outbursts from Aquila X-1 is twofold: (1) studying the relation between optical, soft and hard X-ray emission during the outburst onset, development and decay; (2) relating the spectral component to thermal and non-thermal processes occurring near the magnetosphere and in the boundary layer of a time-variable accretion disk. Our investigation is based on the BATSE monitoring of Aquila X-1 performed by our group. We observed Aquila X-1 in 1997 and re-analyzed archival information obtained in April 1994 during a period of extraordinary outbursting activity of the source in the hard X-ray range. Our results allow, for the first time for this important source, to obtain simultaneous spectral information from 2 keV to 200 keV. A black body (T = 0.8 keV) plus a broken power-law spectrum describe accurately the 1994 spectrum. Substantial hard X-ray emission is evident in the data, confirming that the accretion phase during sub-Eddington limit episodes is capable of producing energetic hard emission near 5 x 10(exp 35) ergs(exp -1). A preliminary paper summarizes our results, and a more comprehensive account is being written. We performed a theoretical analysis of possible emission mechanisms, and confirmed that a non-thermal emission mechanism triggered in a highly sheared magnetosphere at the accretion disk inner boundary can explain the hard X-ray emission. An anticorrelation between soft and hard X-ray emission is indeed prominently observed as predicted by this model.

  16. Final Report on Small Particle Speciation for Forensics Analysis by Soft X-ray Scanning Transmission X-ray Microscopy

    SciTech Connect

    Pacold, J. I.; Altman, A. B.; Donald, S B; Dai, Z.; Davisson, M. L.; Holliday, K S; Knight, K. B.; Kristo, M. J.; Minasian, S. G.; Nelson, A J; Tyliszczak, T; Booth, C. H.; Shuh, D. K.

    2016-09-30

    Materials of interest for nuclear forensic science are often highly heterogeneous, containing complex mixtures of actinide compounds in a wide variety of matrices. Scanning transmission X-ray microscopy (STXM) is ideally suited to study such materials, as it can be used to chemically image specimens by acquiring X-ray absorption near-edge spectroscopy (XANES) data with 25 nm spatial resolution. In particular, STXM in the soft X-ray synchrotron radiation regime (approximately 120 – 2000 eV) can collect spectroscopic information from the actinides and light elements in a single experiment. Thus, STXM combines the chemical sensitivity of X-ray absorption spectroscopy with high spatial resolution in a single non-destructive characterization method. This report describes the application of STXM to a broad range of nuclear materials. Where possible, the spectroscopic images obtained by STXM are compared with information derived from other analytical methods, and used to make inferences about the process history of each material. STXM measurements can yield information including the morphology of a sample, “elemental maps” showing the spatial distribution of major chemical constituents, and XANES spectra from localized regions of a sample, which may show spatial variations in chemical composition.

  17. A multichannel cryogenic detector system for synchrotron-based x-ray spectroscopy

    NASA Astrophysics Data System (ADS)

    Friedrich, S.; Niedermayr, T.; Funk, T.; Drury, O.; van den Berg, M. L.; Cunningham, M. F.; Ullom, J. N.; Loshak, A.; Cramer, S. P.; Frank, M.; Labov, S. E.

    2002-02-01

    Fluorescence-detected x-ray absorption spectroscopy probes the fine structure of electronic energy levels with sub-eV resolution by scanning a monochromatic synchrotron beam through the corresponding absorption edge and measuring the intensity of the resulting x-ray fluorescence. For dilute samples, grating spectrometers lack the detection efficiency and conventional Si(Li) or Ge detectors often lack the energy resolution to separate the weak fluorescence signal from strong nearby emission lines. We have built a high-resolution, high-efficiency cryogenic detector system for synchrotron-based soft x-ray spectroscopy. The sensor is a 3×3 array of 200 μm×200 μm superconducting Nb-Al-AlOx-Al-Nb tunnel junctions with an energy resolution of ~15 eV below 1 keV and a total count rate capability of ~100,000 counts/second. This sensor array is cooled to below 0.4 K by a two-stage adiabatic demagnetization refrigerator while held at the end of a 40-cm-long cold finger that can be inserted into a UHV sample chamber for x-ray fluorescence measurements. We present absorption spectra of dilute compounds (~1000 ppm) and will discuss spectrometer performance with respect to the analysis of metalloproteins. .

  18. In-situ observations of catalytic surface reactions with soft x-rays under working conditions.

    PubMed

    Toyoshima, Ryo; Kondoh, Hiroshi

    2015-03-04

    Catalytic chemical reactions proceeding on solid surfaces are an important topic in fundamental science and industrial technologies such as energy conversion, pollution control and chemical synthesis. Complete understanding of the heterogeneous catalysis and improving its efficiency to an ultimate level are the eventual goals for many surface scientists. Soft x-ray is one of the prime probes to observe electronic and structural information of the target materials. Most studies in surface science using soft x-rays have been performed under ultra-high vacuum conditions due to the technical limitation, though the practical catalytic reactions proceed under ambient pressure conditions. However, recent developments of soft x-ray based techniques operating under ambient pressure conditions have opened a door to the in-situ observation of materials under realistic environments. The near-ambient-pressure x-ray photoelectron spectroscopy (NAP-XPS) using synchrotron radiation enables us to observe the chemical states of surfaces of condensed matters under the presence of gas(es) at elevated pressures, which has been hardly conducted with the conventional XPS technique. Furthermore, not only the NAP-XPS but also ambient-pressure compatible soft x-ray core-level spectroscopies, such as near-edge absorption fine structure (NEXAFS) and x-ray emission spectroscopy (XES), have been significantly contributing to the in-situ observations. In this review, first we introduce recent developments of in-situ observations using soft x-ray techniques and current status. Then we present recent new findings on catalytically active surfaces using soft x-ray techniques, particularly focusing on the NAP-XPS technique. Finally we give a perspective on the future direction of this emerging technique.

  19. Review of soft x-ray lasers and their applications

    SciTech Connect

    Skinner, C.H.

    1991-03-01

    The emerging technology of soft x-ray lasers is in a transition phase between the first laboratory demonstrations of gain and the acceptance of soft x-ray 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 future of soft x-ray lasers for a variety of applications. Advanced soft x-ray laser concepts are being developed from investigations into ultra-high intensity laser/matter interactions. The first paper a brief historical perspective of x-ray microscopy and holography have begun. In this paper a brief historical perspective of x-ray 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.

  20. Development of soft x-ray lasers at PALS

    NASA Astrophysics Data System (ADS)

    Rus, Bedrich; Kozlova, Michaela; Polan, Jiri; Praeg, Ansgar R.; Stupka, Michal; Mocek, T.

    2005-03-01

    Program of development of deeply saturated Ne-like zinc soft X-ray laser at the PALS (Prague Asterix Laser System) Centre, employing as a pump device a kilojoule high-power iodine laser, is reviewed. The active medium giving rise to laser action at 21.2 nm is generated using a sequence of multiple-100-ns IR pump pulses, consisting of a weak prepulse (<10J), followed after 10 or 50 ns by the main pump pulse (~500 J). The population inversion in the resulting long scale-length density plasma allows to generate an extremely bright and narrowly collimated X-ray laser beam, providing up to ~10 mJ pulses and ~100 MW of peak power, which is the most powerful soft X-ray laser yet implemented. This device was recently used as radiation source in pilot radiobiology study of DNA damage in the soft X-ray region, and in material ablation. A novel interferometric device, based on double Lloyd's mirror, is being developed for surface nanometric probing with teh soft X-ray laser as a source. A test experiment was performed to assess focusing properties of the X-ray laser beam down to a narrow spot, with the ultimate goal of achieving 1013 Wcm-2 for novel applications relevant to e.g. laboratory astrophysics.

  1. Picosecond x-ray diagnostics for third and fourth generation synchrotron sources

    SciTech Connect

    DeCamp, Matthew

    2016-03-30

    In the DOE-EPSCoR State/National Laboratory partnership grant ``Picosecond x-ray diagnostics for third and fourth generation synchrotron sources'' Dr. DeCamp set forth a partnership between the University of Delaware and Argonne National Laboratory. This proposal aimed to design and implement a series of experiments utilizing, or improving upon, existing time-domain hard x-ray spectroscopies at a third generation synchrotron source. Specifically, the PI put forth three experimental projects to be explored in the grant cycle: 1) implementing a picosecond ``x-ray Bragg switch'' using a laser excited nano-structured metallic film, 2) designing a robust x-ray optical delay stage for x-ray pump-probe studies at a hard x-ray synchrotron source, and 3) building/installing a laser based x-ray source at the Advanced Photon Source for two-color x-ray pump-probe studies.

  2. In situ synchrotron based x-ray techniques as monitoring tools for atomic layer deposition

    SciTech Connect

    Devloo-Casier, Kilian Detavernier, Christophe; Dendooven, Jolien

    2014-01-15

    Atomic layer deposition (ALD) is a thin film deposition technique that has been studied with a variety of in situ techniques. By exploiting the high photon flux and energy tunability of synchrotron based x-rays, a variety of new in situ techniques become available. X-ray reflectivity, grazing incidence small angle x-ray scattering, x-ray diffraction, x-ray fluorescence, x-ray absorption spectroscopy, and x-ray photoelectron spectroscopy are reviewed as possible in situ techniques during ALD. All these techniques are especially sensitive to changes on the (sub-)nanometer scale, allowing a unique insight into different aspects of the ALD growth mechanisms.

  3. First Terrestrial Soft X-ray Aurora Observations by Chandra

    NASA Technical Reports Server (NTRS)

    Bhardwaj, Anil; Elsner, Ronald F.; Gladstone, G. Randall; Waite, J. Hunter, Jr.; Cravens, Thomas E.; Ostgaard, Nikolai; Chang, Shen-Wu; Metzger, Albert E.; Majeed, Tariq

    2004-01-01

    Northern polar "auroral" regions of Earth was observed by High-Resolution Camera in imaging mode (T32C-I) aboard Chandra X-Ray Observatory (CXO) during mid December 2003 - mid April 2004. Ten CXO observations, each approximately 20 min duration, were made in a non-conventional method (due to CXO technical issues), such that Chandra was aimed at a fixed point in sky and the Earth's polar cusp was allowed to drift through the HRC-I field-of-view. The observations were performed when CXO was near apogee and timed during northern winter mostly near midnight (6 hr), except two observations which occurred around 1200 UT, so that northern polar region is entirely in dark and solar fluoresced x-ray contamination can be avoided. These observations were aimed at searching the Earth's soft x-ray aurora and to do a comparative study with Jupiter's x-ray aurora, where a pulsating x-ray hot-spot near the northern magnetic pole has been observed by Chandra that implies a particle source region near Jupiter's magnetopause, and entry of heavy solar wind ions due to high-latitude reconnection as a viable explanation for the soft x-ray emissions. The first Chandra soft (0.1-2 keV) x-ray observations of Earth's aurora show that it is highly variable (intense arc, multiple arcs, diffuse, at times almost absent). In at least one of the observations an isolated blob of emission is observed where we expect cusp to be: giving indication of solar wind charge-exchange signature in x-rays. We are comparing the Chandra x-ray observations with observations at other wavelengths and particle data from Earth-orbiting satellites and solar wind measurements from near-Earth ACE and SOH0 spacecraft. Preliminary results from these unique CXO-Earth observations will be presented and discussed.

  4. Soft X-ray spectroscopy of nanoparticles by velocity map imaging

    NASA Astrophysics Data System (ADS)

    Kostko, O.; Xu, B.; Jacobs, M. I.; Ahmed, M.

    2017-07-01

    Velocity map imaging (VMI), a technique traditionally used to study chemical dynamics in the gas phase, is applied here to study X-ray photoemission from aerosol nanoparticles. Soft X-rays from the Advanced Light Source synchrotron, probe a beam of nanoparticles, and the resulting photoelectrons are velocity mapped to obtain their kinetic energy distributions. A new design of the VMI spectrometer is described. The spectrometer is benchmarked by measuring vacuum ultraviolet photoemission from gas phase xenon and squalene nanoparticles followed by measurements using soft X-rays. It is demonstrated that the photoelectron distribution from X-ray irradiated squalene nanoparticles is dominated by secondary electrons. By scanning the photon energies and measuring the intensities of these secondary electrons, a near edge X-ray absorption fine structure (NEXAFS) spectrum is obtained. The NEXAFS technique is used to obtain spectra of aqueous nanoparticles at the oxygen K edge. By varying the position of the aqueous nanoparticle beam relative to the incident X-ray beam, evidence is presented such that the VMI technique allows for NEXAFS spectroscopy of water in different physical states. Finally, we discuss the possibility of applying VMI methods to probe liquids and solids via X-ray spectroscopy.

  5. Soft X-ray spectroscopy of nanoparticles by velocity map imaging.

    PubMed

    Kostko, O; Xu, B; Jacobs, M I; Ahmed, M

    2017-07-07

    Velocity map imaging (VMI), a technique traditionally used to study chemical dynamics in the gas phase, is applied here to study X-ray photoemission from aerosol nanoparticles. Soft X-rays from the Advanced Light Source synchrotron, probe a beam of nanoparticles, and the resulting photoelectrons are velocity mapped to obtain their kinetic energy distributions. A new design of the VMI spectrometer is described. The spectrometer is benchmarked by measuring vacuum ultraviolet photoemission from gas phase xenon and squalene nanoparticles followed by measurements using soft X-rays. It is demonstrated that the photoelectron distribution from X-ray irradiated squalene nanoparticles is dominated by secondary electrons. By scanning the photon energies and measuring the intensities of these secondary electrons, a near edge X-ray absorption fine structure (NEXAFS) spectrum is obtained. The NEXAFS technique is used to obtain spectra of aqueous nanoparticles at the oxygen K edge. By varying the position of the aqueous nanoparticle beam relative to the incident X-ray beam, evidence is presented such that the VMI technique allows for NEXAFS spectroscopy of water in different physical states. Finally, we discuss the possibility of applying VMI methods to probe liquids and solids via X-ray spectroscopy.

  6. Biological applications of cryo-soft X-ray tomography.

    PubMed

    Duke, E; Dent, K; Razi, M; Collinson, L M

    2014-08-01

    X-rays are used for imaging many different types of biological specimen, ranging from live organisms to the individual cells and proteins from which they are made. The level of detail achieved as a result of the imaging varies depending on both the sample and the technique used. One of the most recent technical developments in X-ray imaging is that of the soft X-ray microscope, designed to allow the internal structure of individual biological cells to be explored. With a field of view of ∼10-20 × ∼10-20 μm, a penetration depth of ∼10 μm and a resolution of ∼40 nm(3), the soft X-ray microscope neatly fits between the imaging capabilities of light and electron microscopes. © 2014 The Authors Journal of Microscopy © 2014 Royal Microscopical Society.

  7. Soft x-ray imager onboard ASTRO-H

    NASA Astrophysics Data System (ADS)

    Tsunemi, Hiroshi; Hayashida, Kiyoshi; Nakajima, Hiroshi; Tsuru, Takeshi Go; Tanaka, Takaaki; Dotani, Tadayasu; Ozaki, Masayuki; Natsukari, Chikara; Tomida, Hiroshi; Hiraga, Junko S.; Kohmura, Takayoshi; Murakami, Hiroshi; Mori, Koji; Yamauchi, Makoto; Hatsukade, Isamu; Bamba, Aya

    2013-09-01

    The Soft X-ray Imager, SXI, is an X-ray CCD camera onboard the ASTRO-H satellite to be launched in 2015. ASTRO-H will carry two types of soft X-ray detector. The X-ray calorimeter, SXS, has an excellent energy resolution with a narrow field of view while the SXI has a medium energy resolution with a large field of view, 38' square. We employ 4 CCDs of P-channel type with a depletion layer of 200 μm. Having passed the CDR, we assemble the FM so that we can join the final assembly. We present here the SXI status and its expected performance in orbit.

  8. Evaluation of RBC aggregation using synchrotron X-ray speckles

    NASA Astrophysics Data System (ADS)

    Ha, Hojin; Nam, Kwon-Ho; Lee, Sang Joon

    2010-11-01

    When a coherent beam illuminates spatially-disordered particles, speckles are usually generated by the inference of the scattered light waves. The speckle has been known to contain the information of the objects under near-field condition. In this study, we hypothesized that the speckle patterns of the red blood cells are related to the aggregation shape and the size of RBCs in the medium. The speckle patterns of RBCs in static condition were investigated by transmitting the monochromatic synchrotron X-ray beam to the sample with varying hematocrit(10-80 %) and medium type(phosphate buffered saline, autologous plasma and 0.75 % polyvinylpyrrolidone 360 in phosphate buffered saline). The temporal variation of speckle patterns after sudden removal of shear rate was observed by stopping the blood flow in a tube. The size of aggregated RBCs is closely correlated with the characteristic features of the speckle patterns.

  9. Development of an x-ray microprobe using synchrotron radiation

    NASA Astrophysics Data System (ADS)

    Thompson, Albert C.; Chapman, Karen L.; Underwood, James H.

    1993-01-01

    An X-ray microprobe is being built that will use a bending magnet port on the new Advanced Light Source (ALS) at the Lawrence Berkeley Laboratory. A pair of elliptical multi-layer mirrors will be used to focus and monochromatize the white radiation beam from the synchrotron. A beam spot size of 1 micrometers X 1 micrometers will be produced with a bandwidth of 1 keV at 10 keV. The energy of the beam will be variable from 3 keV to 12 keV. With a counting time of 30 sec it should be possible to simultaneously measure femtogram amounts of elements from potassium to zinc.

  10. In situ synchrotron x-ray photon beam characterization

    SciTech Connect

    Kyele, Nicholas R.; Silfhout, Roelof G. van; Manolopoulos, Spyros; Nikitenko, S.

    2007-03-15

    We have investigated two in situ methods of measuring x-ray beam parameters such as integrated intensity, position, and intensity distribution. These virtually transparent methods both rely on the collection of scattered radiation from a thin amorphous foil. The scattered radiation is collected by an active pixel sensor placed below the foil, well out of the direction of the beam path. These methods measure a cross-sectional image of the beam as opposed to a profile or beam centroid position provided by existing in situ detection methods. We present the results of measurements taken at a third generation synchrotron radiation source and provide analytical methods of deriving beam profile, position, and absolute intensity.

  11. Synchrotron X-ray diffraction for pyrolytic magnetic carbon

    NASA Astrophysics Data System (ADS)

    Kamishima, K.; Noda, T.; Kadonome, F.; Kakizaki, K.; Hiratsuka, N.

    We have prepared pyrolytic carbon samples from triethylamine and investigated their magnetic and crystallographic properties. The magnetic property depends on pyrolysis temperatures. A ferromagnetic sample with M=5×10-1 emu/g was obtained from the pyrolysis products even at room temperature. The synchrotron X-ray diffraction experiments were performed for the pyrolytic carbon samples in order to see the crystal structure of ferromagnetic samples. Diffraction peaks of iron or iron oxides were not observed for the ferromagnetic samples, whereas the major diffraction peak of the intermediate graphite-diamond (IGD) structure was clearly observed for ferromagnetic and nonmagnetic samples. Therefore, the IGD structure is not the direct cause of ferromagnetism. The ferromagnetism may be related to the graphite-like structure.

  12. Synchrotron x-ray study of multilayers in Laue geometry

    SciTech Connect

    Kang, H C; Stephenson, G B; Liu, C; Conley, R; Macrander, A T; Maser, J; Bajt, S; Chapman, H N

    2004-07-21

    Zone plates with depth to zone-width ratios as large as 100 are needed for focusing of hard x-rays. Such high aspect ratios are challenging to produce by lithography. We are investigating the fabrication of high-aspect-ratio linear zone plates by multilayer deposition followed by sectioning. As an initial step in this work, we present a synchrotron x-ray study of constant-period multilayers diffracting in Laue (transmission) geometry. Data are presented from two samples: a 200 period W/Si multilayer with d-spacing of 29 nm, and a 2020 period Mo/Si multilayer with d-spacing of 7 nm. By cutting and polishing we have successfully produced thin cross sections with section depths ranging from 2 to 12 {micro}m. Transverse scattering profiles (rocking curves) across the Bragg reflection exhibit well-defined interference fringes originating from the depth of the sample, in agreement with dynamical diffraction theory for a multilayer in Laue geometry.

  13. X-ray and synchrotron studies of porous silicon

    SciTech Connect

    Sivkov, V. N.; Lomov, A. A.; Vasil'ev, A. L.; Nekipelov, S. V.; Petrova, O. V.

    2013-08-15

    The results of comprehensive studies of layers of porous silicon of different conductivity types, grown by anodizing standard Si(111) substrates in an electrolyte based on fluoric acid and ethanol with the addition of 5% of iodine and kept in air for a long time, are discussed. Measurements are performed by scanning electron microscopy, high-resolution X-ray diffraction, and ultrasoft X-ray spectroscopy using synchrotron radiation. The structural parameters of the layers (thickness, strain, and porosity) and atomic and chemical composition of the porous-silicon surface are determined. It is found that an oxide layer 1.5-2.3-nm thick is formed on the surface of the silicon skeleton. The near-edge fine structure of the Si 2p absorption spectrum of this layer corresponds to the fine structure of the 2p spectrum of well coordinated SiO{sub 2}. In this case, the fine structure in the Si 2p-edge absorption region of the silicon skeleton is identical to that of the 2p absorption spectrum of crystalline silicon.

  14. Synchrotron X-ray tomographic microscopy of fossil embryos.

    PubMed

    Donoghue, Philip C J; Bengtson, Stefan; Dong, Xi-ping; Gostling, Neil J; Huldtgren, Therese; Cunningham, John A; Yin, Chongyu; Yue, Zhao; Peng, Fan; Stampanoni, Marco

    2006-08-10

    Fossilized embryos from the late Neoproterozoic and earliest Phanerozoic have caused much excitement because they preserve the earliest stages of embryology of animals that represent the initial diversification of metazoans. However, the potential of this material has not been fully realized because of reliance on traditional, non-destructive methods that allow analysis of exposed surfaces only, and destructive methods that preserve only a single two-dimensional view of the interior of the specimen. Here, we have applied synchrotron-radiation X-ray tomographic microscopy (SRXTM), obtaining complete three-dimensional recordings at submicrometre resolution. The embryos are preserved by early diagenetic impregnation and encrustation with calcium phosphate, and differences in X-ray attenuation provide information about the distribution of these two diagenetic phases. Three-dimensional visualization of blastomere arrangement and diagenetic cement in cleavage embryos resolves outstanding questions about their nature, including the identity of the columnar blastomeres. The anterior and posterior anatomy of embryos of the bilaterian worm-like Markuelia confirms its position as a scalidophoran, providing new insights into body-plan assembly among constituent phyla. The structure of the developing germ band in another bilaterian, Pseudooides, indicates a unique mode of germ-band development. SRXTM provides a method of non-invasive analysis that rivals the resolution achieved even by destructive methods, probing the very limits of fossilization and providing insight into embryology during the emergence of metazoan phyla.

  15. The very soft X-ray emission of X-ray-faint early-type galaxies

    NASA Technical Reports Server (NTRS)

    Pellegrini, S.; Fabbiano, G.

    1994-01-01

    A recent reanaylsis of Einstein data, and new ROSAT observations, have revealed the presence of at least two components in the X-ray spectra of X-ray faint early-type galaxies: a relatively hard component (kT greater than 1.5 keV), and a very soft component (kT approximately 0.2-0.3 keV). In this paper we address the problem of the nature of the very soft component and whether it can be due to a hot interstellar medium (ISM), or is most likely originated by the collective emission of very soft stellar sources. To this purpose, hydrodynamical evolutionary sequences for the secular behavior of gas flows in ellipticals have been performed, varying the Type Ia supernovae rate of explosion, and the dark matter amount and distribution. The results are compared with the observational X-ray data: the average Einstein spectrum for six X-ray faint early-type galaxies (among which are NGC 4365 and NGC 4697), and the spectrum obtained by the ROSAT pointed observation of NGC 4365. The very soft component could be entirely explained with a hot ISM only in galaxies such as NGC 4697, i.e., when the depth of the potential well-on which the average ISM temperature strongly depends-is quite shallow; in NGC 4365 a diffuse hot ISM would have a temperature larger than that of the very soft component, because of the deeper potential well. So, in NGC 4365 the softest contribution to the X-ray emission comes certainly from stellar sources. As stellar soft X-ray emitters, we consider late-type stellar coronae, supersoft sources such as those discovered by ROSAT in the Magellanic Clouds and M31, and RS CVn systems. All these candidates can be substantial contributors to the very soft emission, though none of them, taken separately, plausibly accounts entirely for its properties. We finally present a model for the X-ray emission of NGC 4365, to reproduce in detail the results of the ROSAT pointed observation, including the Position Sensitive Proportional Counter (PSPC) spectrum and radial

  16. Soft X-ray spectrographs for solar observations

    NASA Technical Reports Server (NTRS)

    Bruner, M. E.

    1988-01-01

    Recent advances in soft X-ray spectrometery are reviewed, with emphasis on techniques for studying the windowless region from roughly 1-100 A. Recent technological developments considered include multilayer mirrors, large-format CCD detectors which are sensitive to X-rays, position-sensitive photon counting detectors, new kinds of X-ray films, and optical systems based on gratings with nonuniform ruling spacings. Improvements in the extent and accuracy of the atomic physics data sets on which the analysis of spectroscopic observatons depend are also discussed.

  17. Contact microscopy with a soft x-ray laser

    SciTech Connect

    DiCicco, D.S.; Kim, D.; Rosser, R.J.; Skinner, C.H.; Suckewer, S.; Gupta, A.P.; Hirschberg, J.G.

    1989-03-01

    A soft x-ray laser of output energy 1-3 mJ at 19.2 nm has been used to record high resolution images of biological specimens. The contact images were recorded on photoresist which was later viewed in a scanning electron microscope. We also present a Composite Optical X- ray Laser Microscope ''COXRALM'' of novel design. 14 refs., 8 figs., 1 tab.

  18. Soft diffuse X-rays in the southern galactic hemisphere

    NASA Technical Reports Server (NTRS)

    Sanders, W. T.; Kraushaar, W. L.; Nousek, J. A.; Fried, P. M.

    1977-01-01

    A map is presented of the soft X-ray diffuse background flux in the C band (approximately 0.13-0.28 keV) covering almost all of the southern galactic hemisphere. A comparison at constant galactic latitude of both C band and B band (about 0.1-0.18 keV) soft X-ray data with neutral-hydrogen maps shows that the intensity does decrease with increasing neutral-hydrogen column density but in a manner that is inconsistent with photoelectric absorption. It is suggested that the inverse correlation is a displacement effect. X-ray emission regions appear to be where the cool gas is not. Further, the evidence against photoelectric absorption implies that the bulk of the cool gas is beyond the X-ray emitting regions. Fewer than 10 to the 20th power H atoms per sq cm can be between the sun and the X-ray emitting regions. The sun appears to be surrounded by a soft X-ray emission region consisting of gas at a temperature of about 1 million K.

  19. Ground Calibration of the Astro-H (Hitomi) Soft X-Ray Spectrometer

    NASA Technical Reports Server (NTRS)

    Eckart, M. E.; Adams, J. S.; Boyce, K. R.; Brown, G. V.; Chiao, Meng P.; Fujimoto, R. J.; Haas, D.; Den Herder, J. W.; Ishisaki, Y.; Kelley, R. L.; hide

    2016-01-01

    The Astro-H (Hitomi) Soft X-ray Spectrometer (SXS) was a pioneering imaging x-ray spectrometer with 5 eV energy resolution at 6 keV. The instrument used a microcalorimeter array at the focus of a high-throughput soft x-ray telescope to enable high-resolution non-dispersive spectroscopy in the soft x-ray waveband (0.3-12 keV). We present the suite of ground calibration measurements acquired from 2012-2015, including characterization of the detector system, anti-coincidence detector, optical blocking filters, and filter-wheel filters. The calibration of the 36-pixel silicon thermistor microcalorimeter array includes parameterizations of the energy gain scale and line spread function for each event grade over a range of instrument operating conditions, as well as quantum efficiency measurements. The x-ray transmission of the set of five Al/polyimide thin-film optical blocking filters mounted inside the SXS dewar has been modeled based on measurements at synchrotron beamlines, including with high spectral resolution at the C, N, O, and Al K-edges. In addition, we present the x-ray transmission of the dewar gate valve and of the filters mounted on the SXS filter wheel (external to the dewar), including beryllium, polyimide, and neutral density filters.

  20. Ground calibration of the Astro-H (Hitomi) soft x-ray spectrometer

    NASA Astrophysics Data System (ADS)

    Eckart, M. E.; Adams, J. S.; Boyce, K. R.; Brown, G. V.; Chiao, M. P.; Fujimoto, R.; Haas, D.; den Herder, J. W.; Ishisaki, Y.; Kelley, R. L.; Kilbourne, C. A.; Leutenegger, M. A.; McCammon, D.; Mitsuda, K.; Porter, F. S.; Sato, K.; Sawada, M.; Seta, H.; Sneiderman, G. A.; Szymkowiak, A. E.; Takei, Y.; Tashiro, M.; Tsujimoto, M.; de Vries, C. P.; Watanabe, T.; Yamada, S.; Yamasaki, N. Y.

    2016-07-01

    The Astro-H (Hitomi) Soft X-ray Spectrometer (SXS) was a pioneering imaging x-ray spectrometer with 5 eV energy resolution at 6 keV. The instrument used a microcalorimeter array at the focus of a high-throughput soft x-ray telescope to enable high-resolution non-dispersive spectroscopy in the soft x-ray waveband (0:3-12 keV). We present the suite of ground calibration measurements acquired from 2012-2015, including characterization of the detector system, anti-coincidence detector, optical blocking filters, and filter-wheel filters. The calibration of the 36-pixel silicon thermistor microcalorimeter array includes parameterizations of the energy gain scale and line spread function for each event grade over a range of instrument operating conditions, as well as quantum efficiency measurements. The x-ray transmission of the set of five Al/polyimide thin-film optical blocking filters mounted inside the SXS dewar has been modeled based on measurements at synchrotron beamlines, including with high spectral resolution at the C, N, O, and Al K-edges. In addition, we present the x-ray transmission of the dewar gate valve and of the filters mounted on the SXS filter wheel (external to the dewar), including beryllium, polyimide, and neutral density filters.

  1. New Homogeneous Standards by Atomic Layer Deposition for Synchrotron X-ray Fluorescence and Absorption Spectroscopies.

    SciTech Connect

    Butterworth, A.L.; Becker, N.; Gainsforth, Z.; Lanzirotti, A.; Newville, M.; Proslier, T.; Stodolna, J.; Sutton, S.; Tyliszczak, T.; Westphal, A.J.; Zasadzinski, J.

    2012-03-13

    Quantification of synchrotron XRF analyses is typically done through comparisons with measurements on the NIST SRM 1832/1833 thin film standards. Unfortunately, these standards are inhomogeneous on small scales at the tens of percent level. We are synthesizing new homogeneous multilayer standards using the Atomic Layer Deposition technique and characterizing them using multiple analytical methods, including ellipsometry, Rutherford Back Scattering at Evans Analytical, Synchrotron X-ray Fluorescence (SXRF) at Advanced Photon Source (APS) Beamline 13-ID, Synchrotron X-ray Absorption Spectroscopy (XAS) at Advanced Light Source (ALS) Beamlines 11.0.2 and 5.3.2.1 and by electron microscopy techniques. Our motivation for developing much-needed cross-calibration of synchrotron techniques is borne from coordinated analyses of particles captured in the aerogel of the NASA Stardust Interstellar Dust Collector (SIDC). The Stardust Interstellar Dust Preliminary Examination (ISPE) team have characterized three sub-nanogram, {approx}1{micro}m-sized fragments considered as candidates to be the first contemporary interstellar dust ever collected, based on their chemistries and trajectories. The candidates were analyzed in small wedges of aerogel in which they were extracted from the larger collector, using high sensitivity, high spatial resolution >3 keV synchrotron x-ray fluorescence spectroscopy (SXRF) and <2 keV synchrotron x-ray transmission microscopy (STXM) during Stardust ISPE. The ISPE synchrotron techniques have complementary capabilities. Hard X-ray SXRF is sensitive to sub-fg mass of elements Z {ge} 20 (calcium) and has a spatial resolution as low as 90nm. X-ray Diffraction data were collected simultaneously with SXRF data. Soft X-ray STXM at ALS beamline 11.0.2 can detect fg-mass of most elements, including cosmochemically important oxygen, magnesium, aluminum and silicon, which are invisible to SXRF in this application. ALS beamline 11.0.2 has spatial resolution

  2. The study of diffuse soft X-ray background

    NASA Astrophysics Data System (ADS)

    Gupta, Anjali

    The cosmic X-ray background was discovered at the dawn of the X-ray astronomy: during the first successful rocket flight launched to study the X-ray emission from the Moon, the presence of a residual diffuse emission was also "serendipitously" revealed. In the intervening decades, observations with improving angular and spectral resolution have enhanced our understanding of the components that make up this background. Above 1 keV, the emission is highly isotropic on large angular scales, has extragalactic origin, and about ~80 percent has been resolved into discrete sources (Mushotzky et al. 2000, Hasinger et al. 1998). Our current interpretation of the diffuse X-ray emission below 1 keV uses a combination of 5 components, solar wind charge exchange, Local Bubble, Galactic halo, intergalactic gas, and unresolved point sources. Resolving the different components is made particularly difficult by the similar spectral emission of most components, X-ray lines of heavily ionized metals, which are poorly resolved by the energy resolution of CCD cameras onboard current X-ray satellites with typical observing times. The goal of this investigation is to assess the integral emission of the major components of the diffuse Soft X-Ray Background. In the first part of my project, I analyzed the shadow observations performed with XMM-Newton and Suzaku X-ray observatories. Shadow observations offer a tool to separate the fore ground component, due to the Local Bubble and, possibly, charge exchange within the solar system, from the background component, due primarily to the Galactic Halo and unidentified point sources. In the second part of my project, I studied the contribution of unresolved point sources and intergalactic medium to the diffuse Soft X-ray Background.

  3. Reabsorption of Soft X-Ray Emission at High X-Ray Free-Electron Laser Fluences

    NASA Astrophysics Data System (ADS)

    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

    2014-10-01

    We report on oxygen K-edge soft x-ray 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 x-ray fluences. In addition the total emission yield decreases at high fluences. These modifications result from reabsorption of x-ray emission by valence-excited molecules generated by the Auger cascade. Our observations have major implications for future x-ray emission studies at intense x-ray sources. We highlight the importance of the x-ray pulse length with respect to the core-hole lifetime.

  4. Reabsorption of soft x-ray emission at high x-ray free-electron laser fluences.

    PubMed

    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

    2014-10-10

    We report on oxygen K-edge soft x-ray 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 x-ray fluences. In addition the total emission yield decreases at high fluences. These modifications result from reabsorption of x-ray emission by valence-excited molecules generated by the Auger cascade. Our observations have major implications for future x-ray emission studies at intense x-ray sources. We highlight the importance of the x-ray pulse length with respect to the core-hole lifetime.

  5. High pressure x-ray diffraction techniques with synchrotron radiation

    NASA Astrophysics Data System (ADS)

    Jing, Liu

    2016-07-01

    This article summarizes the developments of experimental techniques for high pressure x-ray diffraction (XRD) in diamond anvil cells (DACs) using synchrotron radiation. Basic principles and experimental methods for various diffraction geometry are described, including powder diffraction, single crystal diffraction, radial diffraction, as well as coupling with laser heating system. Resolution in d-spacing of different diffraction modes is discussed. More recent progress, such as extended application of single crystal diffraction for measurements of multigrain and electron density distribution, time-resolved diffraction with dynamic DAC and development of modulated heating techniques are briefly introduced. The current status of the high pressure beamline at BSRF (Beijing Synchrotron Radiation Facility) and some results are also presented. Project supported by the National Natural Science Foundation of China (Grant Nos. 10875142, 11079040, and 11075175). The 4W2 beamline of BSRF was supported by the Chinese Academy of Sciences (Grant Nos. KJCX2-SW-N20, KJCX2-SW-N03, and SYGNS04).

  6. Bright circularly polarized soft X-ray high harmonics for X-ray magnetic circular dichroism

    DOE PAGES

    Fan, Tingting; Grychtol, Patrik; Knut, Ronny; ...

    2015-11-03

    Here, we demonstrate, to our knowledge, the first bright circularly polarized high-harmonic beams in the soft X-ray region of the electromagnetic spectrum, and use them to implement X-ray magnetic circular dichroism measurements in a tabletop-scale setup. Using counterrotating circularly polarized laser fields at 1.3 and 0.79 µm, we generate circularly polarized harmonics with photon energies exceeding 160 eV. The harmonic spectra emerge as a sequence of closely spaced pairs of left and right circularly polarized peaks, with energies determined by conservation of energy and spin angular momentum. We explain the single-atom and macroscopic physics by identifying the dominant electron quantummore » trajectories and optimal phase-matching conditions. The first advanced phase-matched propagation simulations for circularly polarized harmonics reveal the influence of the finite phase-matching temporal window on the spectrum, as well as the unique polarization-shaped attosecond pulse train. Finally, we use, to our knowledge, the first tabletop X-ray magnetic circular dichroism measurements at the N4,5 absorption edges of Gd to validate the high degree of circularity, brightness, and stability of this light source. These results demonstrate the feasibility of manipulating the polarization, spectrum, and temporal shape of high harmonics in the soft X-ray region by manipulating the driving laser waveform.« less

  7. Bright circularly polarized soft X-ray high harmonics for X-ray magnetic circular dichroism.

    PubMed

    Fan, Tingting; Grychtol, Patrik; Knut, Ronny; Hernández-García, Carlos; Hickstein, Daniel D; Zusin, Dmitriy; Gentry, Christian; Dollar, Franklin J; Mancuso, Christopher A; Hogle, Craig W; Kfir, Ofer; Legut, Dominik; Carva, Karel; Ellis, Jennifer L; Dorney, Kevin M; Chen, Cong; Shpyrko, Oleg G; Fullerton, Eric E; Cohen, Oren; Oppeneer, Peter M; Milošević, Dejan B; Becker, Andreas; Jaroń-Becker, Agnieszka A; Popmintchev, Tenio; Murnane, Margaret M; Kapteyn, Henry C

    2015-11-17

    We demonstrate, to our knowledge, the first bright circularly polarized high-harmonic beams in the soft X-ray region of the electromagnetic spectrum, and use them to implement X-ray magnetic circular dichroism measurements in a tabletop-scale setup. Using counterrotating circularly polarized laser fields at 1.3 and 0.79 µm, we generate circularly polarized harmonics with photon energies exceeding 160 eV. The harmonic spectra emerge as a sequence of closely spaced pairs of left and right circularly polarized peaks, with energies determined by conservation of energy and spin angular momentum. We explain the single-atom and macroscopic physics by identifying the dominant electron quantum trajectories and optimal phase-matching conditions. The first advanced phase-matched propagation simulations for circularly polarized harmonics reveal the influence of the finite phase-matching temporal window on the spectrum, as well as the unique polarization-shaped attosecond pulse train. Finally, we use, to our knowledge, the first tabletop X-ray magnetic circular dichroism measurements at the N4,5 absorption edges of Gd to validate the high degree of circularity, brightness, and stability of this light source. These results demonstrate the feasibility of manipulating the polarization, spectrum, and temporal shape of high harmonics in the soft X-ray region by manipulating the driving laser waveform.

  8. Bright circularly polarized soft X-ray high harmonics for X-ray magnetic circular dichroism

    PubMed Central

    Fan, Tingting; Grychtol, Patrik; Knut, Ronny; Hernández-García, Carlos; Hickstein, Daniel D.; Zusin, Dmitriy; Gentry, Christian; Dollar, Franklin J.; Mancuso, Christopher A.; Hogle, Craig W.; Kfir, Ofer; Legut, Dominik; Carva, Karel; Ellis, Jennifer L.; Dorney, Kevin M.; Chen, Cong; Shpyrko, Oleg G.; Fullerton, Eric E.; Cohen, Oren; Oppeneer, Peter M.; Milošević, Dejan B.; Becker, Andreas; Jaroń-Becker, Agnieszka A.; Popmintchev, Tenio; Murnane, Margaret M.; Kapteyn, Henry C.

    2015-01-01

    We demonstrate, to our knowledge, the first bright circularly polarized high-harmonic beams in the soft X-ray region of the electromagnetic spectrum, and use them to implement X-ray magnetic circular dichroism measurements in a tabletop-scale setup. Using counterrotating circularly polarized laser fields at 1.3 and 0.79 µm, we generate circularly polarized harmonics with photon energies exceeding 160 eV. The harmonic spectra emerge as a sequence of closely spaced pairs of left and right circularly polarized peaks, with energies determined by conservation of energy and spin angular momentum. We explain the single-atom and macroscopic physics by identifying the dominant electron quantum trajectories and optimal phase-matching conditions. The first advanced phase-matched propagation simulations for circularly polarized harmonics reveal the influence of the finite phase-matching temporal window on the spectrum, as well as the unique polarization-shaped attosecond pulse train. Finally, we use, to our knowledge, the first tabletop X-ray magnetic circular dichroism measurements at the N4,5 absorption edges of Gd to validate the high degree of circularity, brightness, and stability of this light source. These results demonstrate the feasibility of manipulating the polarization, spectrum, and temporal shape of high harmonics in the soft X-ray region by manipulating the driving laser waveform. PMID:26534992

  9. Synchrotron x-ray sources and new opportunities in the soil and environmental sciences

    SciTech Connect

    Schulze, D. ); Anderson, S. ); Mattigod, S. )

    1990-07-01

    This report contains the following papers: characteristics of the advanced photon source and comparison with existing synchrotron facilities; x-ray absorption spectroscopy: EXAFS and XANES -- A versatile tool to study the atomic and electronic structure of materials; applications of x-ray spectroscopy and anomalous scattering experiments in the soil and environmental sciences; X-ray fluorescence microprobe and microtomography.

  10. X-ray and synchrotron methods in studies of cultural heritage sites

    NASA Astrophysics Data System (ADS)

    Koval'chuk, M. V.; Yatsishina, E. B.; Blagov, A. E.; Tereshchenko, E. Yu.; Prosekov, P. A.; Dyakova, Yu. A.

    2016-09-01

    X-ray and synchrotron methods that are most widely used in studies of cultural heritage objects (including archaeological sites)—X-ray diffraction analysis, X-ray spectroscopy, and visualization techniques— have been considered. The reported examples show high efficiency and informativeness of natural science studies when solving most diverse problems of archaeology, history, the study of art, museology, etc.

  11. Picosecond resolution soft x-ray laser plasma interferometry

    SciTech Connect

    Moon, S; Nilsen, J; Ng, A; Shlyaptsev, V; Dunn, J; Hunter, J; Keenan, R; Marconi, M; Filevich, J; Rocca, J; Smith, R

    2003-12-01

    We describe a soft x-ray laser interferometry technique that allows two-dimensional diagnosis of plasma electron density with picosecond time resolution. It consists of the combination of a robust high throughput amplitude division interferometer and a 14.7 nm transient inversion soft x-ray laser that produces {approx} 5 ps pulses. Due to its picosecond resolution and short wavelength scalability, this technique has potential for extending the high inherent precision of soft x-ray laser interferometry to the study of very dense plasmas of significant fundamental and practical interest, such as those investigated for inertial confined fusion. Results of its use in the diagnostics of dense large scale laser-created plasmas are presented.

  12. Fast fluctuations of soft X-rays from active regions

    NASA Technical Reports Server (NTRS)

    Simnett, G. F.; Dennis, B. R.

    1986-01-01

    A selection of short lived small soft X-ray bursts is studied using data from the Hard X-ray Imaging Spectrometer (HXIS), and the results are compared with the data from the Hard X-Ray Burst Spectrometer (HXRBS) with a view to understanding conditions at the onset of flares. Short-lived events provide an opportunity to study the radiation from the primary energy transfer process without confusion from the slowly-varying thermal X-ray emission which characterizes the decay of a large flare. The fast decay of the soft X-rays, only a few tens of seconds, suggests that they occur in the dense chromosphere. The results indicate that the short events may be signatures of several different phenomena, depending on their characteristics. Some events occur in association with reverse-drift type III bursts and simultaneous flaring elsewhere on the Sun, thus suggesting dumping of particles accelerated at a remote site. Some events have hard X-ray bursts and normal type III bursts associated with them, while others have neither. The latter events place strong constraints on the nonthermal electron population present.

  13. Soft X-Ray Irradiation of Silicates: Implications for Dust Evolution in Protoplanetary Disks

    NASA Astrophysics Data System (ADS)

    Ciaravella, A.; Cecchi-Pestellini, C.; Chen, Y.-J.; Muñoz Caro, G. M.; Huang, C.-H.; Jiménez-Escobar, A.; Venezia, A. M.

    2016-09-01

    The processing of energetic photons on bare silicate grains was simulated experimentally on silicate films submitted to soft X-rays of energies up to 1.25 keV. The silicate material was prepared by means of a microwave assisted sol-gel technique. Its chemical composition reflects the Mg2SiO4 stoichiometry with residual impurities due to the synthesis method. The experiments were performed using the spherical grating monochromator beamline at the National Synchrotron Radiation Research Center in Taiwan. We found that soft X-ray irradiation induces structural changes that can be interpreted as an amorphization of the processed silicate material. The present results may have relevant implications in the evolution of silicate materials in X-ray-irradiated protoplanetary disks.

  14. Imaging Magnetic Nanostructures via Resonant Soft X-Ray Spectro Holography

    NASA Astrophysics Data System (ADS)

    Hellwig, Olav; Eisebitt, Stefan; Guenther, Christian; Menzel, Andreas; Radu, Florin; Pfau, Bastian; Eberhardt, Wolfgang; Schlotter, William; Rick, Ramon; Scherz, Andreas; Luening, Jan; Stoehr, Joachim; McNulty, Ian

    2007-03-01

    We will present how to exploit the coherence and tunable polarization of soft X-ray synchrotron radiation for imaging magnetic nanostructures via Fourier Transform Holography. This new lensless imaging technique is based on the direct Fourier inversion of a holographically formed soft x-ray interference pattern. Our implementation is particularly simple and is based on placing the sample behind a lithographically manufactured mask with a micron-sized sample aperture and a nano-sized reference hole. By exploiting the magnetic dichroism in resonance at the L3 edges of the magnetic transition metals, images of magnetic nanostructures have been obtained with a spatial resolution of 50 nm. Different examples will be presented. The technique is transferable to a wide variety of specimen, appears scalable to diffraction-limited resolution (about 2 nm), and is well suited for ultra-fast single-shot imaging with future X-ray free electron laser sources.

  15. Soft X-ray Absorption Edges in LMXBs

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The XMM observation of LMC X-2 is part of our program to study X-ray absorption in the interstellar medium (ISM). This program includes a variety of bright X-ray binaries in the Galaxy as well as the Magellanic Clouds (LMC and SMC). LMC X-2 is located near the heart of the LMC. Its very soft X-ray spectrum is used to determine abundance and ionization fractions of neutral and lowly ionized oxygen of the ISM in the LMC. The RGS spectrum so far allowed us to determine the O-edge value to be for atomic O, the EW of O-I in the ls-2p resonance absorption line, and the same for O-II. The current study is still ongoing in conjunction with other low absorption sources like Sco X-1 and the recently observed X-ray binary 4U 1957+11.

  16. Geoscience Applications of Synchrotron X-ray Computed Microtomography

    NASA Astrophysics Data System (ADS)

    Rivers, M. L.

    2009-05-01

    Computed microtomography is the extension to micron spatial resolution of the CAT scanning technique developed for medical imaging. Synchrotron sources are ideal for the method, since they provide a monochromatic, parallel beam with high intensity. High energy storage rings such as the Advanced Photon Source at Argonne National Laboratory produce x-rays with high energy, high brilliance, and high coherence. All of these factors combine to produce an extremely powerful imaging tool for earth science research. Techniques that have been developed include: - Absorption and phase contrast computed tomography with spatial resolution approaching one micron - Differential contrast computed tomography, imaging above and below the absorption edge of a particular element - High-pressure tomography, imaging inside a pressure cell at pressures above 10GPa - High speed radiography, with 100 microsecond temporal resolution - Fluorescence tomography, imaging the 3-D distribution of elements present at ppm concentrations. - Radiographic strain measurements during deformation at high confining pressure, combined with precise x- ray diffraction measurements to determine stress. These techniques have been applied to important problems in earth and environmental sciences, including: - The 3-D distribution of aqueous and organic liquids in porous media, with applications in contaminated groundwater and petroleum recovery. - The kinetics of bubble formation in magma chambers, which control explosive volcanism. - Accurate crystal size distributions in volcanic systems, important for understanding the evolution of magma chambers. - The equation-of-state of amorphous materials at high pressure using both direct measurements of volume as a function of pressure and also by measuring the change x-ray absorption coefficient as a function of pressure. - The formation of frost flowers on Arctic sea-ice, which is important in controlling the atmospheric chemistry of mercury. - The distribution of

  17. Soft X ray properties of the Geminga pulsar

    NASA Astrophysics Data System (ADS)

    Halpern, J. P.; Ruderman, M.

    1993-01-01

    The ROSAT soft x ray spectrum and pulse profile of the Geminga pulsar are analyzed and interpreted in terms of thermal emission from the surface of the neutron star. The x ray spectrum appears to consist of two blackbody components with T1 = (5.2 +/- 1.0) x 10 5 K and T2 approximately 3 x 106 K, respectively. The inferred ratio of surface areas, A2/A1, is approximately 3 x 10-5. Both components are highly modulated at the pulsar rotation period, but the harder x ray pulse is narrower, and leads the main (soft) x ray pulse by about 105 deg of phase. The soft x ray component is interpreted as photospheric cooling of much of the neutron star's surface area, while the small, hot region could be part of the much smaller polar cap heated by energetic particles flowing inward from the magnetospheric accelerator which is responsible for the production of Geminga's gamma rays. Geminga's gamma ray emission is consistent with outer-magnetosphere accelerator models for highly inclined dipoles. These predict the beaming of energetic gamma rays close enough to the star to give copious e(+/-) production in the stellar magnetic field and a large circumstellar pair density from pair inflow toward the surface. These pairs may quench radio emission, and also reflect most of the hard polar cap x rays back to the stellar surface by cyclotron resonance scattering. They are then reemitted from that much larger area at the lower temperature T1. The single-peaked nature of the x ray pulse and its energy-dependent phase suggest an off-center dipole geometry for the surface magnetic field. Under the assumption that the soft x ray emission comes from the full surface of a neutron star of radius R = 10 km, a distance estimate of (150-400) pc is derived. This range is consistent with the fit interstellar column density of (1.5 +/- 0.5) x 1020 cm-2. Distances less than 150 pc are probably ruled out both by the lower limit on the column density, and also by the requirement that the Rayleigh

  18. K-Edge Subtraction Angiography with Synchrotron X-Rays

    SciTech Connect

    Giacomini, John C.

    1996-12-31

    The purpose of this project was to utilize dual energy, monochromatic X-rays produced from synchrotrons radiation in order to obtain noninvasive medical imaging. The application of synchrotrons radiation to medical imaging is based on the principle of iodine dichromography, first described by Bertil Jacobson of the Karolinska Institute in 1953. Medical imaging using synchrotrons radiation and K-edge dichromography was pioneered at Stanford University under the leadership of Dr. Ed Rubenstein, and the late Nobel Laureate in Physics, Dr. Robert Hofstadter. With progressive refinements in hardware, clinical-quality images were obtained of human coronary arteries utilizing peripheral injections of iodinated contrast agent. These images even now are far superior to those being presented by investigators using MRI as an imaging tool for coronary arteries. However, new supplies and instruments in the cardiac catheterization laboratory have served to transform coronary angiography into an outpatient procedure, with relatively little morbidity. We extended the principles learned with coronary angiography to noninvasive imaging of the human bronchial tree. For these images, we utilized xenon as the contrast agent, as it has a K-edge very similar to that of iodine. In this case, there is no true competing diagnostic test, and pulmonary neoplasm is an enormous public health concern. In early experiments, we demonstrated remarkably clear images of the human bronchial tree. These images have been shown internationally; however, funding difficulties primarily with the Department of Energy have not allowed for progression of this promising avenue of research. One potential criticism of the project is that in order to obtain these images, we utilized national laboratories. Some have questioned whether this would lead to a practical imaging modality. However, we have shown that the technology exists to allow for construction of a miniature storage ring, with a superconducting

  19. Soft X-ray techniques to study mesoscale magnetism

    SciTech Connect

    Kortright, Jeffrey B.

    2003-06-26

    Heterogeneity in magnetization (M) is ubiquitous in modern systems. Even in nominally homogeneous materials, domains or pinning centers typically mediate magnetization reversal. Fundamental lengths determining M structure include the domain wall width and the exchange stiffness length, typically in the 4-400 nm range. Chemical heterogeneity (phase separation, polycrystalline microstructure, lithographic or other patterning, etc.) with length scales from nanometers to microns is often introduced to influence magnetic properties. With 1-2 nm wavelengths {lambda}, soft x-rays in principle can resolve structure down to {lambda}/2, and are well suited to study these mesoscopic length scales [1, 2]. This article highlights recent advances in resonant soft x-ray methods to resolve lateral magnetic structure [3], and discusses some of their relative merits and limitations. Only techniques detecting x-ray photons (rather than photo-electrons) are considered [4], since they are compatible with strong applied fields to probe relatively deeply into samples. The magneto-optical (MO) effects discovered by Faraday and Kerr were observed in the x-ray range over a century later, first at ''hard'' wavelengths in diffraction experiments probing interatomic magnetic structure [5]. In the soft x-ray range, magnetic linear [6] and circular [7] dichroism spectroscopies first developed that average over lateral magnetic structure. These large resonant MO effects enable different approaches to study magnetic structure or heterogeneity that can be categorized as microscopy or scattering [1]. Direct images of magnetic structure result from photo-emission electron microscopes [4, 8] and zone-plate microscopes [9, 10]. Scattering techniques extended into the soft x-ray include familiar specular reflection that laterally averages over structure but can provide depth-resolved information, and diffuse scattering and diffraction that provide direct information about lateral magnetic structure

  20. Electronic Properties of Hydrogen Storage Materials with Photon-in/Photon-out Soft-X-Ray Spectroscopy

    SciTech Connect

    Guo, Jinghua

    2008-09-22

    The applications of resonant soft X-ray emission spectroscopy on a variety of carbon systems have yielded characteristic fingerprints. With high-resolution monochromatized synchrotron radiation excitation, resonant inelastic X-ray scattering has emerged as a new source of information about electronic structure and excitation dynamics. Photon-in/photon-out soft-X-ray spectroscopy is used to study the electronic properties of fundamental materials, nanostructure, and complex hydrides and will offer potential in-depth understanding of chemisorption and/or physisorption mechanisms of hydrogen adsorption/desorption capacity and kinetics.

  1. Soft x-ray virtual diagnostics for tokamak simulations

    SciTech Connect

    Kim, J. S.; Zhao, L.; Bogatu, I. N.; In, Y.; Turnbull, A.; Osborne, T.; Maraschek, M.; Comer, K.

    2009-11-15

    The numerical toolset, FAR-TECH Virtual Diagnostic Utility, for generating virtual experimental data based on theoretical models and comparing it with experimental data, has been developed for soft x-ray diagnostics on DIII-D. The virtual (or synthetic) soft x-ray signals for a sample DIII-D discharge are compared with the experimental data. The plasma density and temperature radial profiles needed in the soft x-ray signal modeling are obtained from experimental data, i.e., from Thomson scattering and electron cyclotron emission. The virtual soft x-ray diagnostics for the equilibriums have a good agreement with the experimental data. The virtual diagnostics based on an ideal linear instability also agree reasonably well with the experimental data. The agreements are good enough to justify the methodology presented here for utilizing virtual diagnostics for routine comparison of experimental data. The agreements also motivate further detailed simulations with improved physical models such as the nonideal magnetohydrodynamics contributions (resistivity, viscosity, nonaxisymmetric error fields, etc.) and other nonlinear effects, which can be tested by virtual diagnostics with various stability modeling.

  2. Lensless imaging of nanoporous glass with soft X-rays

    DOE PAGES

    Turner, Joshua J.; Nelson, Johanna; Huang, Xiaojing; ...

    2013-06-01

    Coherent soft X-ray diffraction has been used to image nanoporous glass structure in two dimensions using different methods. The merit of the reconstructions was judged using a new method of Fourier phase correlation with a final, refined image. The porous structure was found to have a much larger average size then previously believed.

  3. Lasers, extreme UV and soft X-ray

    SciTech Connect

    Nilsen, Joseph

    2015-09-20

    Three decades ago, large ICF lasers that occupied entire buildings were used as the energy sources to drive the first X-ray lasers. Today X-ray lasers are tabletop, spatially coherent, high-repetition rate lasers that enable many of the standard optical techniques such as interferometry to be extended to the soft X-ray regime between wavelengths of 10 and 50 nm. Over the last decade X-ray laser performance has been improved by the use of the grazing incidence geometry, diode-pumped solid-state lasers, and seeding techniques. The dominant X-ray laser schemes are the monopole collisional excitation lasers either driven by chirped pulse amplification (CPA) laser systems or capillary discharge. The CPA systems drive lasing in neon-like or nickel-like ions, typically in the 10 – 30 nm range, while the capillary system works best for neon-like argon at 46.9 nm. Most researchers use nickel-like ion lasers near 14 nm because they are well matched to the Mo:Si multilayer mirrors that have peak reflectivity near 13 nm and are used in many applications. As a result, the last decade has seen the birth of the X-ray free electron laser (XFEL) that can reach wavelengths down to 0.15 nm and the inner-shell Ne laser at 1.46 nm.

  4. Synchrotron X-ray diagnostics of cutoff shape of nonthermal electron spectrum at young supernova remnants

    NASA Astrophysics Data System (ADS)

    Yamazaki, Ryo; Ohira, Yutaka; Sawada, Makoto; Bamba, Aya

    2014-02-01

    Synchrotron X-rays can be a useful tool to investigate electron acceleration at young supernova remnants (SNRs). At present, since the magnetic field configuration around the shocks of SNRs is uncertain, it is not clear whether electron acceleration is limited by SNR age, synchrotron cooling, or even escape from the acceleration region. We study whether the acceleration mechanism can be constrained by the cutoff shape of the electron spectrum around the maximum energy. We derive analytical formulae of the cutoff shape in each case where the maximum electron energy is determined by SNR age, synchrotron cooling and escape from the shock. They are related to the energy dependence of the electron diffusion coefficient. Next, we discuss whether information on the cutoff shape can be provided by observations in the near future which will simply give the photon indices and the flux ratios in the soft and hard X-ray bands. We find that if the power-law index of the electron spectrum is independently determined by other observations, then we can constrain the cutoff shape by comparing theoretical predictions of the photon indices and/or the flux ratios with observed data which will be measured by NuSTAR and/or ASTRO-H. Such study is helpful in understanding the acceleration mechanism. In particular, it will supply another independent constraint on the magnetic field strength around the shocks of SNRs.

  5. CT imaging of small animals using monochromatized synchrotron x rays

    SciTech Connect

    Dilmanian, F.A.; Rarback, H.; Nachaliel, E.; Rivers, M.; Thomlinson, W.C.; Chapman, L.D.; Oversluizen, T.; Slatkin, D.N.; Spanne, P.; Spector, S.; Garrett, R.F.; Luke, P.N.; Pehl, R.; Thompson, A.C.; Appel, R.; Miller, M.H.

    1992-12-31

    Rats and chicken embryos were imaged in vivo with a prototype Multiple Energy Computed Tomography (MECT) system using monochromatized x rays from the X17 superconducting wiggler at the National Synchrotron Light Source. The CT configuration coated of a horizontal low-divergence, fan-shaped beam, 70 mm wide and 0.5 mm high, and a subject rotating about a vertical aids. A linear-array high-purity Ge detector with 140 elements, each 0.5 mm wide and 6 mm thick, was used with a data acquisition system that provides a linear response over almost six orders of magnitude of detector current. The dual photon absorptiometry (DPA) algorithm was applied to images of the rat head acquired at 20 and 45 keV to obtain two new images, one representing the low-Z, and the other the intermediate-Z clement group. The results indicate that the contrast resolution and the quantification accuracy of the images improve stepwise; first, with the monochromatic beam and, second, the DPA method. The system is a prototype for a brain scanner.

  6. CT imaging of small animals using monochromatized synchrotron x rays

    SciTech Connect

    Dilmanian, F.A.; Rarback, H.; Nachaliel, E.; Rivers, M.; Thomlinson, W.C.; Chapman, L.D.; Oversluizen, T.; Slatkin, D.N.; Spanne, P.; Spector, S. ); Garrett, R.F. ); Luke, P.N.; Pehl, R.; Thompson, A.C. ); Appel, R.; Miller, M.H. (A

    1992-01-01

    Rats and chicken embryos were imaged in vivo with a prototype Multiple Energy Computed Tomography (MECT) system using monochromatized x rays from the X17 superconducting wiggler at the National Synchrotron Light Source. The CT configuration coated of a horizontal low-divergence, fan-shaped beam, 70 mm wide and 0.5 mm high, and a subject rotating about a vertical aids. A linear-array high-purity Ge detector with 140 elements, each 0.5 mm wide and 6 mm thick, was used with a data acquisition system that provides a linear response over almost six orders of magnitude of detector current. The dual photon absorptiometry (DPA) algorithm was applied to images of the rat head acquired at 20 and 45 keV to obtain two new images, one representing the low-Z, and the other the intermediate-Z clement group. The results indicate that the contrast resolution and the quantification accuracy of the images improve stepwise; first, with the monochromatic beam and, second, the DPA method. The system is a prototype for a brain scanner.

  7. Investigating biomineralization using synchrotron based X-ray computed microtomography

    NASA Astrophysics Data System (ADS)

    Armstrong, Ryan; Ajo-Franklin, Jonathan

    2011-04-01

    This work presents the results of a study where synchrotron based x-ray computed microtomography (CMT) was used to investigate changes in pore morphology during calcium carbonate biomineralization. We simultaneously examine changes in pore microstructure and bulk permeability within glass bead columns during biogenic CaCO3 precipitation induced by Sporosarcina pasteurii. We observe a three order of magnitude reduction in permeability over relatively short time-scales (˜60 hrs) during the carbonate precipitation process. The resulting precipitates were a micro-porous composite of spherical and cubic CaCO3 precipitates. CMT images taken during precipitation were analyzed for effective pore radii, effective throat radii, and other pore-scale characteristics using 3DMA-ROCK. The Kozeny-Carman relation provided a poor fit to the raw permeability data, however, once this function was augmented with geometric information extracted from CMT imagery a better fit was provided suggesting that pore geometry should be considered temporally variable when modeling permeability change during biomineralization.

  8. Microbial biofilm study by synchrotron X-ray microscopy

    NASA Astrophysics Data System (ADS)

    Pennafirme, S.; Lima, I.; Bitencourt, J. A.; Crapez, M. A. C.; Lopes, R. T.

    2015-11-01

    Microbial biofilm has already being used to remove metals and other pollutants from wastewater. In this sense, our proposal was to isolate and cultivate bacteria consortia from mangrove's sediment resistant to Zn (II) and Cu (II) at 50 mg L-1 and to observe, through synchrotron X-ray fluorescence microscopy (microXRF), whether the biofilm sequestered the metal. The biofilm area analyzed was 1 mm2 and a 2D map was generated (pixel size 20×20 μm2, counting time 5 s/point). The biofilm formation and retention followed the sequence Zn>Cu. Bacterial consortium zinc resistant formed dense biofilm and retained 63.83% of zinc, while the bacterial consortium copper resistant retained 3.21% of copper, with lower biofilm formation. Dehydrogenase activity of Zn resistant bacterial consortium was not negatively affect by 50 mg ml-1 zinc input, whereas copper resistant bacterial consortium showed a significant decrease on dehydrogenase activity (50 mg mL-1 of Cu input). In conclusion, biofilm may protect bacterial cells, acting as barrier against metal toxicity. The bacterial consortia Zn resistant, composed by Nitratireductor spp. and Pseudomonas spp formed dense biofilm and sequestered metal from water, decreasing the metal bioavailability. These bacterial consortia can be used in bioreactors and in bioremediation programs.

  9. Investigating biomineralization using synchrotron based X-ray computed microtomography

    SciTech Connect

    Armstrong, Ryan; Ajo-Franklin, Jonathan

    2011-01-01

    This work presents the results of a study where synchrotron based x-ray computed microtomography (CMT) was used to investigate changes in pore morphology during calcium carbonate biomineralization. We simultaneously examine changes in pore microstructure and bulk permeability within glass bead columns during biogenic CaCO₃ precipitation induced by Sporosarcina pasteurii. We observe a three order of magnitude reduction in permeability over relatively short time-scales (~60 hrs) during the carbonate precipitation process. The resulting precipitates were a micro-porous composite of spherical and cubic CaCO₃ precipitates. CMT images taken during precipitation were analyzed for effective pore radii, effective throat radii, and other pore-scale characteristics using 3DMA-ROCK. The Kozeny-Carman relation provided a poor fit to the raw permeability data, however, once this function was augmented with geometric information extracted from CMT imagery a better fit was provided suggesting that pore geometry should be considered temporally variable when modeling permeability change during biomineralization.

  10. Fluorescent scanning x-ray tomography with synchrotron radiation

    NASA Astrophysics Data System (ADS)

    Takeda, Tohoru; Maeda, Toshikazu; Yuasa, Tetsuya; Akatsuka, Takao; Ito, Tatsuo; Kishi, Kenichi; Wu, Jin; Kazama, Masahiro; Hyodo, Kazuyuki; Itai, Yuji

    1995-02-01

    Fluorescent scanning (FS) x-ray tomography was developed to detect nonradioactive tracer materials (iodine and gadolinium) in a living object. FS x-ray tomography consists of a silicon (111) channel cut monochromator, an x-ray shutter, an x-ray slit system and a collimator for detection, a scanning table for the target organ, and an x-ray detector with pure germanium. The minimal detectable dose of iodine in this experiment was 100 ng in a volume of 2 mm3 and a linear relationship was shown between the photon counts of a fluorescent x ray and the concentration of iodine contrast material. A FS x-ray tomographic image was clearly obtained with a phantom.

  11. Resonant soft x-ray reflectivity of polymer bilayers

    NASA Astrophysics Data System (ADS)

    Wang, Cheng

    2005-03-01

    Hard x-ray reflectivity is a very successful and common tool to measure thin film thickness, roughness, and interfacial widths in bilayers. However, hard x-rays have low or even insufficient contrast for a number of polymer species. For this reason, neutron reflectivity is often used in which the contrast can be enhanced enormously by deuterating one species. Alternatively, x-ray reflectivity capabilities could be extended by enhancing the contrast between layers through resonant methods near absorption edges. We are in the process of evaluating if soft x- ray resonant reflectivity is a valuable complement to hard x-ray and neutron reflectivity. Measurements were performed on PS/PMMA and PS/P2VP bilayer structures near the carbon-1s and nitrogen-1s or oxygen 1s K absorption edges on samples with individual layer thicknesses of 10-40 nm. At these photon energies the scattering factors f1 and f2 can be varied substantially, amounting to ?turning on and off? PS and PMMA or P2VP selectively. Large differences in reflected intensity have indeed been observed as a function of photon energy in θ-2θ measurements. We are in the process of characterizing the intrinsic limitation of interfacial width measurements and the limitations on film thickness due the longer wavelength and lower penetration power of soft X-rays. - Data acquired at the X-ray Calibrations and Standards beamline 6.3.2 at the Advanced Light Source at the Berkeley National Laboratory. Research supported by U.S. DoE.

  12. Laser plasma soft X-ray source based on cryogenic target

    NASA Astrophysics Data System (ADS)

    Amano, Sho

    2017-05-01

    Laser plasma soft X-ray sources that operate in the water window and are based on cryogenic targets have been studied. The cryogenic targets used are composed of solid layers of inert gases and are deposition-free targets, which is advantageous for continuous long-lifetime operation using repetitive pulses. The developed laser plasma source has a translating substrate system with a closed He gas cryostat that can continuously supply the cryogenic target, and the source can generate repetitive X-ray pulses continuously. Cryogenic solid Ar and N2 targets were compared for the soft X-ray source when operating in the water window between 2.3 nm and 4.4 nm. The intensity of the water window Xrays from the Ar target was approximately eight times stronger than that from the N2 target at a laser intensity of 5×1012 W/cm2 . At this laser intensity, the Ar plasma source also demonstrated a higher conversion efficiency of 14% and an average power of 140 mW in the water window for a laser energy of 1 J at 1 Hz. This power compares favorably with that of X-rays produced using a synchrotron radiation source. The results also indicated that our source satisfied the requirements for use as a source for a contact X-ray microscope. The developed laser plasma source can be used not only for soft X-ray microscopy but also may be used to replace synchrotron facilities in a variety of other applications.

  13. High Resolution X-Ray Microangiography of 4T1 Tumor in Mouse Using Synchrotron Radiation

    SciTech Connect

    Sun Jianqi; Liu Ping; Gu Xiang; Liu Xiaoxia; Zhao Jun; Xiao Tiqiao; Xu, Lisa X.

    2010-07-23

    Angiogenesis is very important in tumor growth and metastasis. But in clinic, only vessels lager than 200 {mu}m in diameter, can be observed using conventional medical imaging. Synchrotron radiation (SR) phase contrast imaging, whose spatial resolution can reach as high as 1 {mu}m, has great advantages in imaging soft tissue structures, such as blood vessels and tumor tissues. In this paper, the morphology of newly formed micro-vessels in the mouse 4T1 tumor samples was firstly studied with contrast agent. Then, the angiogenesis in nude mice tumor window model was observed without contrast agent using the SR phase contrast imaging at the beamline for X-ray imaging and biomedical applications, Shanghai Synchrotron Radiation Facility (SSRF). The images of tumors showed dense, irregular and tortuous tumor micro-vessels with the smallest size of 20-30 {mu}m in diameter.

  14. The Solar-A soft X-ray telescope experiment

    NASA Technical Reports Server (NTRS)

    Acton, L.; Bruner, M.; Brown, W.; Lemen, J.; Hirayama, T.

    1988-01-01

    The Japanese Solar-A mission for the study of high energy solar physics is timed to observe the sun during the next activity maximum. This small spacecraft includes a carefully coordinated complement of instruments for flare studies. In particular, the soft X-ray telescope (SXT) will provide X-ray images of flares with higher sensitivity and time resolution than have been available before. This paper describes the scientific capabilities of the SXT and illustrates its application to the study of an impulsive compact flare.

  15. Optimizing soft X-ray NEXAFS spectroscopy in the laboratory

    NASA Astrophysics Data System (ADS)

    Mantouvalou, I.; Jonas, A.; Witte, K.; Jung, R.; Stiel, H.; Kanngießer, B.

    2017-05-01

    Near edge X-ray absorption fine structure (NEXAFS) spectroscopy in the soft X-ray range is feasible in the laboratory using laser-produced plasma sources. We present a study using seven different target materials for optimized data analysis. The emission spectra of the materials with atomic numbers ranging from Z = 6 to Z = 79 show distinct differences, rendering the adapted selection of a suitable target material for specialized experiments feasible. For NEXAFS spectroscopy a 112.5 nm thick polyimide film is investigated as a reference exemplifying the superiority of quasi-continuum like emission spectra.

  16. A Feasibility Experiment for a Soft X-Ray Laser

    DTIC Science & Technology

    1976-09-01

    AFWL-TR-76-107 ( )FWL-TR- 76-107 A FEASIBILITY EXPERIMENT FOR A SOFT X-RAY LASER September 1976 Final Report Approved for public release...Introduction 29 The Utah Experiment 29 Other Hard X-ray Laser Considerations 29 V SUMMARY Conclusions 31 A4CEUI@N lV Future Directions 31 IT4 whie... Experimental Chamber 23 4 Sketch of Vacuum Chamber 24 ii AFWL-TR-76-107 SECTION I INTRODUCTION 1. SYNOPSIS The purpose of this report is to present an

  17. Real time observation of mouse fetal skeleton using a high resolution X-ray synchrotron

    PubMed Central

    Chang, Dong Woo; Kim, Bora; Shin, Jae Hoon; Yun, Young Min; Je, Jung Ho; Hwu, Yeu kuang; Yoon, Jung Hee

    2011-01-01

    The X-ray synchrotron is quite different from conventional radiation sources. This technique may expand the capabilities of conventional radiology and be applied in novel manners for special cases. To evaluate the usefulness of X-ray synchrotron radiation systems for real time observations, mouse fetal skeleton development was monitored with a high resolution X-ray synchrotron. A non-monochromatized X-ray synchrotron (white beam, 5C1 beamline) was employed to observe the skeleton of mice under anesthesia at embryonic day (E)12, E14, E15, and E18. At the same time, conventional radiography and mammography were used to compare with X-ray synchrotron. After synchrotron radiation, each mouse was sacrificed and stained with Alizarin red S and Alcian blue to observe bony structures. Synchrotron radiation enabled us to view the mouse fetal skeleton beginning at gestation. Synchrotron radiation systems facilitate real time observations of the fetal skeleton with greater accuracy and magnification compared to mammography and conventional radiography. Our results show that X-ray synchrotron systems can be used to observe the fine structures of internal organs at high magnification. PMID:21586868

  18. Soft x-ray diagnostics for pulsed power machines

    SciTech Connect

    Idzorek, G.C.; Coulter, W.L.; Walsh, P.J.; Montoya, R.R.

    1995-08-01

    A variety of soft x-ray diagnostics are being fielded on the Los Alamos National Laboratory Pegasus and Procyon pulsed power systems and also being fielded on joint US/Russian magnetized target fusion experiments known as MAGO (Magnitoye Obzhatiye). The authors have designed a low-cost modular photoemissive detector designated the XRD-96 that uses commercial 1100 series aluminum for the photocathode. In addition to photocathode detectors a number of designs using solid state silicon photodiodes have been designed and fielded. They also present a soft x-ray time-integrated pinhole camera system that uses standard type TMAX-400 photographic film that obviates the need for expensive and no longer produced zero-overcoat soft x-ray emulsion film. In a typical experiment the desired spectral energy cuts, signal intensity levels, and desired field of view will determine diagnostic geometry and x-ray filters selected. The authors have developed several computer codes to assist in the diagnostic design process and data deconvolution. Examples of the diagnostic design process and data analysis for a typical pulsed power experiment are presented.

  19. In situ Monitoring of Synchrotron X-Ray-Induced Radiolysis Effects on Chromium Species Using X-Ray Absorption Spectroscopy

    NASA Astrophysics Data System (ADS)

    Men, S.; Anderson, A. J.; Mayanovic, R. A.

    2017-05-01

    Synchrotron X-ray radiolysis-induced redox in a chromium aqueous solution was monitored using in situ X-ray absorption spectroscopy. The radiolysis in the fluid sample within a specifically designed hydrothermal diamond anvil cell caused the oxidation of Cr(III) to Cr(VI) upon heating from room temperature to 400°C, and reduction of Cr(VI) to Cr(III) at 500°C. The two fitted components of the pre-edge features of the Cr K-edge spectra were used to identify the presence of Cr(VI) in the solution.

  20. An x-ray microprobe using focussing optics with a synchrotron radiation source

    SciTech Connect

    Thompson, A.C.; Underwood, J.H.; Wu, Y.; Giauque, R.D.

    1989-01-01

    An x-ray microprobe can be used to produce maps of the concentration of elements in a sample. Synchrotron radiation provides x-ray beams with enough intensity and collimation to make possible elemental images with femtogram sensitivity. The use of focussing x-ray mirrors made from synthetic multilayers with a synchrotron x-ray beam allows beam spot sizes of less than 10 /mu/m /times/ 10 /mu/m to be produced. Since minimal sample preparation is required and a vacuum environment is not necessary, there will be a wide variety of applications for such microprobes. 8 refs., 6 figs.

  1. Design Concept and Performance of the Soft X-ray Beamline HiSOR-BL14

    SciTech Connect

    Sawada, M.; Namatame, H.; Yaji, K.; Nagira, M.; Kimura, A.; Taniguchi, M.

    2007-01-19

    The soft X-ray beamline HiSOR-BL14 has been constructed at Hiroshima Synchrotron Radiation Center, aimed at absorption spectroscopy and photoelectron spectroscopy with linearly and circularly polarized light. The beamline layout is based on a Dragon-type design with a spherical grating monochromator. The beamline is able to accept synchrotron radiation from the bending magnet part of the HiSOR ring with a wide solid angle. The large horizontal angular acceptance and vertical one contribute to high photon flux and controllability of light polarization, respectively. Our performance test indicates that high resolving power has been achieved with sufficient photon flux to carry out spectroscopic experiments.

  2. Imaging interfacial micro- and nano-bubbles by scanning transmission soft X-ray microscopy.

    PubMed

    Zhang, Lijuan; Zhao, Binyu; Xue, Lian; Guo, Zhi; Dong, Yaming; Fang, Haiping; Tai, Renzhong; Hu, Jun

    2013-05-01

    Synchrotron-based scanning transmission soft X-ray microscopy (STXM) with nanometer resolution was used to investigate the existence and behavior of interfacial gas nanobubbles confined between two silicon nitride windows. The observed nanobubbles of SF6 and Ne with diameters smaller than 2.5 µm were quite stable. However, larger bubbles became unstable and grew during the soft X-ray imaging, indicating that stable nanobubbles may have a length scale, which is consistent with a previous report using atomic force microscopy [Zhang et al. (2010), Soft Matter, 6, 4515-4519]. Here, it is shown that STXM is a promising technique for studying the aggregation of gases near the solid/water interfaces at the nanometer scale.

  3. High spatial resolution soft-x-ray microscopy

    SciTech Connect

    Meyer-Ilse, W.; Medecki, H.; Brown, J.T.

    1997-04-01

    A new soft x-ray microscope (XM-1) with high spatial resolution has been constructed by the Center for X-ray Optics. It uses bending magnet radiation from beamline 6.1 at the Advanced Light Source, and is used in a variety of projects and applications in the life and physical sciences. Most of these projects are ongoing. The instrument uses zone plate lenses and achieves a resolution of 43 nm, measured over 10% to 90% intensity with a knife edge test sample. X-ray microscopy permits the imaging of relatively thick samples, up to 10 {mu}m thick, in water. XM-1 has an easy to use interface, that utilizes visible light microscopy to precisely position and focus the specimen. The authors describe applications of this device in the biological sciences, as well as in studying industrial applications including structured polymer samples.

  4. Exploring nanomagnetism with soft x-ray microscopy

    SciTech Connect

    Fischer, P.; Kim, D.-H.; Mesler, B.L.; Chao, W.; Sakdinawat,A.E.; Anderson, E.H.

    2006-10-30

    Magnetic soft X-ray microscopy images magnetism in nanoscale systems with a spatial resolution down to 15nm provided by state-of-the-art Fresnel zone plate optics. X-ray magnetic circular dichroism (X-MCD) is used as element-specific magnetic contrast mechanism similar to photoemission electron microscopy (PEEM), however, with volume sensitivity and the ability to record the images in varying applied magnetic fields which allows to study magnetization reversal processes at fundamental length scales. Utilizing a stroboscopic pump-probe scheme one can investigate fast spin dynamics with a time resolution down to 70 ps which gives access to precessional and relaxation phenomena as well as spin torque driven domain wall dynamics in nanoscale systems. Current developments in zone plate optics aim for a spatial resolution towards 10nm and at next generation X-ray sources a time resolution in the fsec regime can be envisioned.

  5. Synchrotron X-Ray Synthesized Gold Nanoparticles for Tumor Therapy

    SciTech Connect

    Chien, C. C.; Wang, C. H.; Tseng, P. Y.; Yang, T. Y.; Hua, T. E.; Hwu, Y.; Chen, Y. J.; Chung, K. H.; Je, J. H.; Margaritondo, G.

    2007-01-19

    Highly concentrated gold nanoparticles (20 {+-} 5 nm) were produced by an x-ray irradiation method. The particles were then examined for the interactions between gold and tumor cells under x-ray radiation conditions. The biological effects of gold nanoparticles were investigated in terms of the internalization, cytotoxicity and capability to enhance x-ray radiotherapy. The results of this investigation indicated that x-ray derived gold nanoparticles were nontoxic to CT-26 cell line and immobilized within cytoplasm. The irradiation experiments provided further evidence that gold nanoparticles were capable of enhancing the efficiency of radiotherapy.

  6. Superconducting Detector System for High-Resolution Energy-Dispersive Soft X-Ray Spectroscopy

    SciTech Connect

    Friedrich, S; Niedermayr, T; Drury, O; Funk, T; Frank, M; Labov, S E; Cramer, S

    2001-02-21

    Synchrotron-based soft x-ray spectroscopy is often limited by detector performance. Grating spectrometers have the resolution, but lack the efficiency for the analysis of dilute samples. Semiconducting Si(Li) or Ge detectors are efficient, but often lack the resolution to separate weak signals from strong nearby lines in multi-element samples. Superconducting tunnel junctions (STJs) operated at temperatures below 1 K can be used as high-resolution high-efficiency x-ray detectors. They combine high energy resolution around 10 eV FWHM with the broad band efficiency of energy-dispersive detectors. We have designed a two-stage adiabatic demagnetization refrigerator (ADR) to operate STJ detectors in x-ray fluorescence measurements at beam line 4 of the ALS. We demonstrate the capabilities of such a detector system for fluorescence analysis of dilute metal sites in proteins and inorganic model compounds.

  7. The X-ray Fluorescence Microscopy Beamline at the Australian Synchrotron

    SciTech Connect

    Paterson, D.; Jonge, M. D. de; Howard, D. L.; Lewis, W.; McKinlay, J.; Starritt, A.; Kusel, M.; Ryan, C. G.; Kirkham, R.; Moorhead, G.; Siddons, D. P.

    2011-09-09

    A hard x-ray micro-nanoprobe has commenced operation at the Australian Synchrotron providing versatile x-ray fluorescence microscopy across an incident energy range from 4 to 25 keV. Two x-ray probes are used to collect {mu}-XRF and {mu}-XANES for elemental and chemical microanalysis: a Kirkpatrick-Baez mirror microprobe for micron resolution studies and a Fresnel zone plate nanoprobe capable of 60-nm resolution. Some unique aspects of the beamline design and operation are discussed. An advanced energy dispersive x-ray fluorescence detection scheme named Maia has been developed for the beamline, which enables ultrafast x-ray fluorescence microscopy.

  8. Viewing spin structures with soft x-ray microscopy

    SciTech Connect

    Fischer, Peter

    2010-06-01

    The spin of the electron and its associated magnetic moment marks the basic unit for magnetic properties of matter. Magnetism, in particular ferromagnetism and antiferromagnetism is described by a collective order of these spins, where the interaction between individual spins reflects a competition between exchange, anisotropy and dipolar energy terms. As a result the energetically favored ground state of a ferromagnetic system is a rather complex spin configuration, the magnetic domain structure. Magnetism is one of the eldest scientific phenomena, yet it is one of the most powerful and versatile utilized physical effects in modern technologies, such as in magnetic storage and sensor devices. To achieve highest storage density, the relevant length scales, such as the bit size in disk drives is now approaching the nanoscale and as such further developments have to deal with nanoscience phenomena. Advanced characterization tools are required to fully understand the underlying physical principles. Magnetic microscopes using polarized soft X-rays offer a close-up view into magnetism with unique features, these include elemental sensitivity due to X-ray magnetic dichroism effects as contrast mechanism, high spatial resolution provided by state-of-the-art X-ray optics and fast time resolution limited by the inherent time structure of current X-ray sources, which will be overcome with the introduction of ultrafast and high brilliant X-ray sources.

  9. Ignitron-driven soft flash x-ray generator

    NASA Astrophysics Data System (ADS)

    Sagae, Michiaki; Sato, Eiichi; Ichimaru, Toshio; Obara, Haruo; Sakamaki, Kimio; Takayama, Kazuyoshi; Tamakawa, Yoshiharu

    1997-12-01

    The fundamental study on a soft flash x-ray generator utilizing an ignitron is described. This generator consists of the following essential components: a high-voltage power supply, a high-voltage pulser having an ignitron, an oil diffusion pump, and a flash x-ray tube. The x-ray tube employs a molybdenum anode rod, a pipe-shaped carbon cathode, a polymethylmeth acrylate tube body, and a polyethylene terephthalate x-ray window. The space between the anode and the cathode electrodes (ac space) can be controlled by rotating the anode rod. The high-voltage condenser in the pulser is charged from 40 to 60 kV by the power supply, and the electric charges in the condenser are discharged to the tube by the ignitron through a 2.0 m coaxial cable. Because the maximum anode voltage of the ignitron is 50 kV, a free-air gap switch is employed in order to increase the high-voltage durability. In the present work, the anode electrode is connected to the ground, and the negative high-voltage output is applied to the cathode electrode. The flash x-rays are then produced. The peak cathode voltage and tube current had values of minus 56 kV and 11.5 kA, respectively, with a charging voltage of 60 kV and an ac space of 6.0 mm, and the pulse widths were less than 300 ns.

  10. ASTRO-H Soft X-Ray Telescope (SXT)

    NASA Technical Reports Server (NTRS)

    Soong, Yang; Serlemitsos Peter J.; Okajima, Takashi; Hahne, Devin

    2011-01-01

    ASTRO-H is an astrophysics satellite dedicated for X-ray spectroscopic study non-dispersively and to carry out survey complementally, which will be borne out of US-Japanese collaborative effort. Among the onboard instruments there are four conically approximated Wolter-I X-ray mirrors, among which two of them are soft X-ray mirrors\\ of which the energy range is from a few hundred eV to 15 keY, currently being fabricated in the X-ray Optics Lab at Goddard Space Flight Center. The focal point instruments will be a calorimeter (SXS) and a CCD camera (SXI), respectively. The reflectors of the mirror are made of heat-formed aluminum substrate of the thickness gauged of 152 micron, 229 micron, and 305 micron of the alloy 5052 H-19, followed by epoxy replication on gold-sputtered smooth Pyrex cylindrical mandrels to acquire the X-ray reflective surface. The epoxy layer is 10 micron nominal and surface gold layer of 0.2 micron. Improvements on angular response over the Astro-El/Suzaku mirrors come from error reduction on the figure, the roundness, and the grazing angle/radius mismatching of the reflecting surface, and tighter specs and mechanical strength on supporting structure to reduce the reflector positioning and the assembly errors. In this paper, we report the results of calibration of the engineering model of SXT (EM), and project the quality of the flight mirrors.

  11. Some ideas on the advantages of soft x-rays as imaging particles

    SciTech Connect

    Howells, M.

    1988-07-01

    This paper discusses uses of soft x-rays as imaging particles. Particular topics discussed are: Soft x-ray as a biological probe; overview of x-ray microscope techniques; analysis of the usefulness of x-rays in imaging and microanalysis; and physical radiation damage. 27 refs., 3 figs., 1 tab.

  12. The soft x ray telescope for Solar-A

    NASA Technical Reports Server (NTRS)

    Brown, W. A.; Acton, L. W.; Bruner, M. E.; Lemen, J. R.; Strong, K. T.

    1989-01-01

    The Solar-A satellite being prepared by the Institute for Sapce and Astronautical Sciences (ISAS) in Japan is dedicated to high energy observations of solar flares. The Soft X Ray Telescope (SXT) is being prepared to provide filtered images in the 2 to 60 A interval. The flight model is now undergoing tests in the 1000 foot tunnel at MSFC. Launch will be in September 1991. Earlier resolution and efficiency tests on the grazing incidence mirror have established its performance in soft x rays. The one-piece, two mirror grazing incidence telescope is supported in a strain free mount separated from the focal plane assembly by a carbon-epoxy metering tube whose windings and filler are chosen to minimize thermal and hygroscopic effects. The CCD detector images both the x ray and the concentric visible light aspect telescope. Optical filters provide images at 4308 and 4700 A. The SXT will be capable of producing over 8000 of the smallest partial frame images per day, or fewer but larger images, up to 1024 x 1024 pixel images. Image sequence with two or more of the five x ray analysis filters, with automatic exposure compensation to optimize the charge collection by the CCD detector, will be used to provide plasma diagnostics. Calculations using a differential emission measure code were used to optimize filter selection over the range of emission measure variations and to avoid redundancy, but the filters were chosen primarily to give ratios that are monotonic in plasma temperature.

  13. Soft X-ray spectroscopy of the Cygnus Loop

    NASA Astrophysics Data System (ADS)

    McEntaffer, Randall L.

    My thesis work consisted of the design, fabrication and launch of a sounding rocket payload to observe the spectrum of the soft X-ray emission from the Cygnus Loop supernova remnant. This payload was designated the Cygnus X-ray Emission Spectroscopic Survey (CyXESS) and launched from White Sands Missile Range on November 20th, 2006. The novel X-ray spectrograph incorporated a wire- grid collimator feeding an array of gratings in the extreme off-plane mount which ultimately dispersed the spectrum onto never before flown Gaseous Electron Multiplier (GEM) detectors. This instrument recorded 65 seconds of usable data between 43-49.5 Å in two prominent features. The first feature near 45 Å is dominated by the He-like triplet of O VII in second order with contributions from Mg X and Si IX-Si XII in first order, while the second feature near 47.5 Å is first order S IX and S X. Fits to the spectra give an equilibrium plasma at log( T )=6.2 ( kT e =0.14 keV) and near cosmic abundances. This is consistent with previous observations, which demonstrated that the soft x-ray emission from the Cygnus Loop is dominated by interactions between the initial blast wave with the walls of a precursor formed cavity surrounding the Cygnus Loop.

  14. Soft x-ray laser microscope. Final report

    SciTech Connect

    Suckewer, P.I.

    1990-10-01

    The program consisted of two phases (Phase I and Phase II). The goal of the Phase I (first year program) was to design and construct the Soft X-ray Laser Contact Microscope. Such microscope was constructed and adapted to PPL`s 18.2nm soft X-ray Laser (SXL), which in turn was modified and prepared for microscopy experiments. Investigation of the photoresist response to 18.2nm laser radiation and transmissivity of 0.1m thick silicion-nitride (Si{sub 3}N{sub 4}) windows were important initial works. The goal of the first year of Phase II was to construct X-ray contact microscope in combination with existing optical phase microscope, already used by biologists. In the second year of Phase II study of dehydrated Horeseshoe Crab and Hela cancer cells were performed with COXRALM. Also during Phase II, the Imaging X-Ray Laser Microscope (IXRALM) was designed and constructed. This paper describes the development of each of the microscopes and their application for research.

  15. UV-Visible Absorption Spectroscopy Enhanced X-ray Crystallography at Synchrotron and X-ray Free Electron Laser Sources.

    PubMed

    Cohen, Aina E; Doukov, Tzanko; Soltis, Michael S

    2016-01-01

    This review describes the use of single crystal UV-Visible Absorption micro-Spectrophotometry (UV-Vis AS) to enhance the design and execution of X-ray crystallography experiments for structural investigations of reaction intermediates of redox active and photosensitive proteins. Considerations for UV-Vis AS measurements at the synchrotron and associated instrumentation are described. UV-Vis AS is useful to verify the intermediate state of an enzyme and to monitor the progression of reactions within crystals. Radiation induced redox changes within protein crystals may be monitored to devise effective diffraction data collection strategies. An overview of the specific effects of radiation damage on macromolecular crystals is presented along with data collection strategies that minimize these effects by combining data from multiple crystals used at the synchrotron and with the X-ray free electron laser.

  16. Combined synchrotron X-ray tomography and X-ray powder diffraction using a fluorescing metal foil.

    PubMed

    Kappen, P; Arhatari, B D; Luu, M B; Balaur, E; Caradoc-Davies, T

    2013-06-01

    This study realizes the concept of simultaneous micro-X-ray computed tomography and X-ray powder diffraction using a synchrotron beamline. A thin zinc metal foil was placed in the primary, monochromatic synchrotron beam to generate a divergent wave to propagate through the samples of interest onto a CCD detector for tomographic imaging, thus removing the need for large beam illumination and high spatial resolution detection. Both low density materials (kapton tubing and a piece of plant) and higher density materials (Egyptian faience) were investigated, and elemental contrast was explored for the example of Cu and Ni meshes. The viability of parallel powder diffraction using the direct beam transmitted through the foil was demonstrated. The outcomes of this study enable further development of the technique towards in situ tomography∕diffraction studies combining micrometer and crystallographic length scales, and towards elemental contrast imaging and reconstruction methods using well defined fluorescence outputs from combinations of known fluorescence targets (elements).

  17. Combined synchrotron X-ray tomography and X-ray powder diffraction using a fluorescing metal foil

    NASA Astrophysics Data System (ADS)

    Kappen, P.; Arhatari, B. D.; Luu, M. B.; Balaur, E.; Caradoc-Davies, T.

    2013-06-01

    This study realizes the concept of simultaneous micro-X-ray computed tomography and X-ray powder diffraction using a synchrotron beamline. A thin zinc metal foil was placed in the primary, monochromatic synchrotron beam to generate a divergent wave to propagate through the samples of interest onto a CCD detector for tomographic imaging, thus removing the need for large beam illumination and high spatial resolution detection. Both low density materials (kapton tubing and a piece of plant) and higher density materials (Egyptian faience) were investigated, and elemental contrast was explored for the example of Cu and Ni meshes. The viability of parallel powder diffraction using the direct beam transmitted through the foil was demonstrated. The outcomes of this study enable further development of the technique towards in situ tomography/diffraction studies combining micrometer and crystallographic length scales, and towards elemental contrast imaging and reconstruction methods using well defined fluorescence outputs from combinations of known fluorescence targets (elements).

  18. Quantifying the Exospheric Component of Soft X-ray Emission

    NASA Technical Reports Server (NTRS)

    Kuntz, Kip; Collier, Michael R.; Snowden, Steven L.; Robertson, Ina; Hansen, Kenneth; Cravens, Thomas

    2007-01-01

    High charge state heavy ions in the solar wind exchange charge with ambient neutral gas. This process creates a product ion in an excited state. During the radiative cascade process, EUV and X-ray photons are emitted with energies in the range of about 100 eV to 1 keV. Because the terrestrial exospheric density at the nominal magnetopause location is relatively high, approx. 10 cu cm, solar wind charge exchange, or SWCX, can be observed by Earth-orbiting soft X-ray instruments such as the ROSAT Position Sensitive Proportional Counters (PSPC). In this presentation, we will compare simulated and observed soft Xray emission during an event on August 18-19, 1991 and discuss the role of exospheric SWCX emission for this and other events.

  19. [Soft X-ray reflectometer with laser produced plasma source].

    PubMed

    Chen, Bo; Ni, Qi-liang; Cao, Ji-hong

    2005-03-01

    A soft X-ray reflectometor with laser-produced plasma source developed in the authorial lab is presented for the measurements of efficiencies of gratings, transmission of filter and reflectance of multilayer coatings. The reflectometer is composed of a soft X-ray laser-produced plasma source, a grazing incidence monochromator with a constant deviation angle, a vacuum chamber, a sample table, a photo-electronic unit and a computer controlling unit. The working wavelength is from 8 to 30 nm and the maximum sample size is 130 mm long by 120 mm wide by 120 mm high. In order to test the performances of the reflectometer, the reflectivity of multilayer coatings was obtained by using this device. The measured results agree well with the theoretical calculation. The reproducibility of measured reflectance is +/-0.6%.

  20. Quantifying the Exospheric Component of Soft X-ray Emission

    NASA Technical Reports Server (NTRS)

    Kuntz, Kip; Collier, Michael R.; Snowden, Steven L.; Robertson, Ina; Hansen, Kenneth; Cravens, Thomas

    2007-01-01

    High charge state heavy ions in the solar wind exchange charge with ambient neutral gas. This process creates a product ion in an excited state. During the radiative cascade process, EUV and X-ray photons are emitted with energies in the range of about 100 eV to 1 keV. Because the terrestrial exospheric density at the nominal magnetopause location is relatively high, approx. 10 cu cm, solar wind charge exchange, or SWCX, can be observed by Earth-orbiting soft X-ray instruments such as the ROSAT Position Sensitive Proportional Counters (PSPC). In this presentation, we will compare simulated and observed soft Xray emission during an event on August 18-19, 1991 and discuss the role of exospheric SWCX emission for this and other events.

  1. Large-area avalanche photodiodes for the detection of soft x rays.

    PubMed

    Gullikson, E M; Gramsch, E; Szawlowski, M

    1995-08-01

    The charge-collection efficiency of beveled-edge-type silicon avalanche photodiodes has been determined for soft x rays in the 50-300-eV range. An efficiency of greater than 80% is measured for energies below the Si L absorption edge. The measured efficiency is well described by a model that accounts for absorption in an oxide overlayer and recombination at the front surface of the diode. The avalanche photodiodes are shown to be significantly more sensitive compared with other detectors for pulsed sources such as a laser-produced plasma source. These results are also very encouraging for soft-xray/ extreme-UV applications involving synchrotron radiation.

  2. A Compact Soft X-Ray Microscope using an Electrode-less Z-Pinch Source

    PubMed Central

    Silterra, J; Holber, W

    2009-01-01

    Soft X-rays (< 1Kev) are of medical interest both for imaging and microdosimetry applications. X-ray sources at this low energy present a technological challenge. Synchrotrons, while very powerful and flexible, are enormously expensive national research facilities. Conventional X-ray sources based on electron bombardment can be compact and inexpensive, but low x-ray production efficiencies at low electron energies restrict this approach to very low power applications. Laser-based sources tend to be expensive and unreliable. Energetiq Technology, Inc. (Woburn, MA, USA) markets a 92 eV, 10W(2pi sr) electrode-less Z-pinch source developed for advanced semiconductor lithography. A modified version of this commercial product has produced 400 mW at 430 eV (2pi sr), appropriate for water window soft X-ray microscopy. The US NIH has funded Energetiq to design and construct a demonstration microscope using this source, coupled to a condenser optic, as the illumination system. The design of the condenser optic matches the unique characteristics of the source to the illumination requirements of the microscope, which is otherwise a conventional design. A separate program is underway to develop a microbeam system, in conjunction with the RARAF facility at Columbia University, NY, USA. The objective is to develop a focused, sub-micron beam capable of delivering > 1 Gy/second to the nucleus of a living cell. While most facilities of this type are coupled to a large and expensive particle accelerator, the Z-pinch X-ray source enables a compact, stand-alone design suitable to a small laboratory. The major technical issues in this system involve development of suitable focusing X-ray optics. Current status of these programs will be reported. PMID:20198115

  3. Radiobiological investigations of soft X-rays near carbon, nitrogen, oxygen K-shell edges on Aspergillus oryzae spores.

    PubMed

    Chen, L; Jiang, S P; Wan, L B; Ma, X D; Li, M F

    2008-01-01

    Soft X-rays at carbon, nitrogen, oxygen K-shell edges have special radiobiological effects. Using Aspergillus oryzae spores as sample, the radiation effects of soft X-rays near the K-shell edges of C, N and O elements from synchrotron radiation were investigated. Also the dose depositions of different X-ray energies in spore were discussed. At the same time, the spores were irradiated by gamma rays from 60Co and relative biological effects were compared with those produced by soft X-rays. The results showed that soft X-rays near K-shell edges of O element had higher ability of radiation damage than that of X-rays near K-shell edges of C and N elements as compared with one another. But they all had higher killing abilities per unit dose than that of gamma rays from 60Co. The relative biological effects (RBEs), the comparison of dose to gamma rays at 10% survival level, of the three soft X-rays were 1.65, 1.73 and 1.91, respectively.

  4. A Soft X-ray Imager for MIRAX

    SciTech Connect

    Zand, Jean in 't; Mels, Wim; Heise, John

    2006-06-09

    The flight spare model of the BeppoSAX Wide Field Cameras is being considered as the Soft X-ray Imager for MIRAX. A description is provided of this instrument, the performance of its siblings on BeppoSAX, and the prospects of flying it on MIRAX. Like on BeppoSAX, the instrument on MIRAX will excel in the study of transient phenomena lasting shorter than 1 day.

  5. Solar EUV, XUV and soft X-ray telescope facilities

    NASA Technical Reports Server (NTRS)

    Withbroe, G. L.

    1982-01-01

    Facility class, high resolution instrumentation can enable maximum spatial, spectral and temporal resolutions and provide understanding of the complex physical conditions in the outer solar atmosphere and the mechanisms responsible for these conditions. The scientific rationale for facility class instruments operating in the EUV, XUV, and soft X ray spectral ranges are discussed. Possible configurations for these facilities and priorities for their development are considered.

  6. ASTRO-H Soft X-ray Telescope (SXT)

    NASA Astrophysics Data System (ADS)

    Soong, Yang; Okajima, Takashi; Serlemitsos, Peter J.; Odell, Stephen L.; Ramsey, Brian D.; Gubarev, Mikhail V.; Ishida, Manabu; Maeda, Yoshitomo; Iizuka, Ryo; Hayashi, Takayuki; Tawara, Yuzuru; Furuzawa, Akihiro; Mori, Hideyuki; Miyazawa, Takuya; Kunieda, Hideyo; Awaki, Hisamitsu; Sugita, Satoshi; Tamura, Keisuke; Ishibashi, Kazunori; Izumiya, Takanori; Minami, Sari; Sato, Toshiki; Tomikawa, Kazuki; Kikuchi, Naomichi; Iwase, Toshihiro

    2014-07-01

    ASTRO-H is an astrophysics satellite dedicated for non-dispersive X-ray spectroscopic study on selective celestial X-ray sources. Among the onboard instruments there are four Wolter-I X-ray mirrors of their reflectors' figure in conical approximation. Two of the four are soft X-ray mirrors1, of which the energy range is from a few hundred eV to 15 keV within the effective aperture being defined by the nested reflectors' radius ranging between 5.8 cm to 22.5 cm. The focal point instruments will be a calorimeter (SXS) and a CCD camera (SXI), respectively. The mirrors were in quadrant configuration with photons being reflected consecutively in the primary and secondary stage before converging on the focal plane of 5.6 m away from the interface between the two stages. The reflectors of the mirror are made of heat-formed aluminum substrate of the thickness gauged of 152 μm, 229 μm, and 305 μm of the alloy 5052 H-19, followed by epoxy replication on gold-sputtered smooth Pyrex cylindrical mandrels to acquire the X-ray reflective surface. The epoxy layer is 10 m nominal and surface gold layer of 0.2 μm. Improvements on angular response over its predecessors, e.g. Astro-E1/Suzaku mirrors, come from error reduction on the figure, the roundness, and the grazing angle/radius mismatching of the reflecting surface, and tighter specs and mechanical strength on supporting structure to reduce the reflector positioning and the assembly errors. Each soft x-ray telescope (SXT), SXT-1 or SXT-2, were integrated from four independent quadrants of mirrors. The stray-light baffles, in quadrant configuration, were mounted onto the integrated mirror. Thermal control units were attached to the perimeter of the integrated mirror to keep the mirror within operating temperature in space. The completed instrument went through a series of optical alignment, thus made the quadrant images confocal and their optical axes in parallel to achieve highest throughput possible. Environmental tests

  7. Science Objectives for a Soft X-ray Mission

    NASA Astrophysics Data System (ADS)

    Sibeck, D. G.; Connor, H. K.; Collier, M. R.; Collado-Vega, Y. M.; Walsh, B.

    2016-12-01

    When high charge state solar wind ions exchange electrons with exospheric neutrals, soft X-rays are emitted. In conjunction with flight- proven wide field-of-view soft X-ray imagers employing lobster-eye optics, recent simulations demonstrate the feasibility of imaging magnetospheric density structures such as the bow shock, magnetopause, and cusps. This presentation examines the Heliospheric scientific objectives that such imagers can address. Principal amongst these is the nature of reconnection at the dayside magnetopause: steady or transient, widespread or localized, component or antiparallel as a function of solar wind conditions. However, amongst many other objectives, soft X-ray imagers can provide crucial information concerning the structure of the bow shock as a function of solar wind Mach number and IMF orientation, the presence or absence of a depletion layer, the occurrence of Kelvin-Helmholtz or pressure-pulse driven magnetopause boundary waves, and the effects of radial IMF orientations and the foreshock upon bow shock and magnetopause location.

  8. Modeling the Soft X-Ray During Solar Flares

    NASA Astrophysics Data System (ADS)

    Leaman, C. J.

    2016-12-01

    Solar Radiation can effect our communication and navigation systems here on Earth. In particular, solar X-ray (SXR) and extreme ultraviolet (EUV) radiation is responsible for ionizing (charging) earth's upper atmosphere, and sudden changes in the ionosphere can disrupt high frequency communication systems (e.g. airplane-to-ground) and degrade the location accuracy for GPS navigation. New soft X-ray flare data are needed to study the sources for the SXR radiation and variability of the solar flares and thus help to answer questions if all flares follow the same trend or have different plasma characteristics? In December 2015, the Miniature X-Ray Solar Spectrometer (MinXSS) launched from Cape Canaveral Florida to answer those questions. The MinXSS CubeSat is a miniature satellite that was designed to measure the soft X-ray spectra and study flares in the 1-15 Å wavelength range. So far, the CubeSat has observed more than ten flares. The MinXSS flare data are plotted in energy vs irradiance to display the soft X-ray spectra, and these spectra are compared with different types of CHIANTI models of the soft X-ray radiation. One comparison is for non-flaring spectra using AIA EUV images to identify solar features called active regions, coronal holes, and quiet sun, and then using the fractional area of each feature to calculate a CHIANTI-based spectrum. This comparison reveals how important the active region radiation is for the SXR spectra. A second comparison is for flare spectra to several isothermal models that were created using CHIANTI. The isothermal model comparisons were done with both the raw count spectra from MinXSS and the derived irradiance spectra. This dual comparison helps to validate the irradiance conversion algorithm for MinXSS. Comparisons of the MinXSS data to the models show that flares tend to follow a temperature pattern. Analysis of the MinXSS data can help us understand our sun better, could lead to better forecasts of solar flares, and thus

  9. Soft x ray properties of the Geminga pulsar

    NASA Technical Reports Server (NTRS)

    Halpern, J. P.; Ruderman, M.

    1993-01-01

    The ROSAT soft x ray spectrum and pulse profile of the Geminga pulsar are analyzed and interpreted in terms of thermal emission from the surface of the neutron star. The x ray spectrum appears to consist of two blackbody components with T(sub 1) = (5.2 +/- 1.0) x 10 (exp 5) K and T(sub 2) approximately 3 x 10(exp 6) K, respectively. The inferred ratio of surface areas, A(sub 2)/A(sub 1), is approximately 3 x 10(exp -5). Both components are highly modulated at the pulsar rotation period, but the harder x ray pulse is narrower, and leads the main (soft) x ray pulse by about 105 deg of phase. The soft x ray component is interpreted as photospheric cooling of much of the neutron star's surface area, while the small, hot region could be part of the much smaller polar cap heated by energetic particles flowing inward from the magnetospheric accelerator which is responsible for the production of Geminga's gamma rays. Geminga's gamma ray emission is consistent with outer-magnetosphere accelerator models for highly inclined dipoles. These predict the beaming of energetic gamma rays close enough to the star to give copious e(+/-) production in the stellar magnetic field and a large circumstellar pair density from pair inflow toward the surface. These pairs may quench radio emission, and also reflect most of the hard polar cap x rays back to the stellar surface by cyclotron resonance scattering. They are then reemitted from that much larger area at the lower temperature T(sub 1). The single-peaked nature of the x ray pulse and its energy-dependent phase suggest an off-center dipole geometry for the surface magnetic field. Under the assumption that the soft x ray emission comes from the full surface of a neutron star of radius R = 10 km, a distance estimate of (150-400) pc is derived. This range is consistent with the fit interstellar column density of (1.5 +/- 0.5) x 10(exp 20) cm(exp -2). Distances less than 150 pc are probably ruled out both by the lower limit on the column

  10. Optoelectronic measurement of x-ray synchrotron pulses: A proof of concept demonstration

    NASA Astrophysics Data System (ADS)

    Durbin, Stephen M.; Mahmood, Aamer; Caffee, Marc; Savikhin, Sergei; Dufresne, Eric M.; Wen, Haidan; Li, Yuelin

    2013-02-01

    Optoelectronic detection using photoconductive coplanar stripline devices has been applied to measuring the time profile of x-ray synchrotron pulses, a proof of concept demonstration that may lead to improved time-resolved x-ray studies. Laser sampling of current vs time delay between 12 keV x-ray and 800 nm laser pulses reveal the ˜50 ps x-ray pulse width convoluted with the ˜200 ps lifetime of the conduction band carriers. For GaAs implanted with 8 MeV protons, a time profile closer to the x-ray pulse width is observed. The protons create defects over the entire depth sampled by the x-rays, trapping the x-ray excited conduction electrons and minimizing lifetime broadening of the electrical excitation.

  11. Optoelectronic measurement of x-ray synchrotron pulses: A proof of concept demonstration

    SciTech Connect

    Durbin, Stephen M.; Caffee, Marc; Savikhin, Sergei; Mahmood, Aamer; Dufresne, Eric M.; Wen, Haidan; Li, Yuelin

    2013-02-04

    Optoelectronic detection using photoconductive coplanar stripline devices has been applied to measuring the time profile of x-ray synchrotron pulses, a proof of concept demonstration that may lead to improved time-resolved x-ray studies. Laser sampling of current vs time delay between 12 keV x-ray and 800 nm laser pulses reveal the {approx}50 ps x-ray pulse width convoluted with the {approx}200 ps lifetime of the conduction band carriers. For GaAs implanted with 8 MeV protons, a time profile closer to the x-ray pulse width is observed. The protons create defects over the entire depth sampled by the x-rays, trapping the x-ray excited conduction electrons and minimizing lifetime broadening of the electrical excitation.

  12. Large-area avalanche photodiodes for the detection of soft x rays

    SciTech Connect

    Gullikson, E.M.; Gramsch, E. |; Szawlowski, M.

    1995-08-01

    The charge-collection efficiency of beveled-edge-type silicon avalanche photodiodes has been determined for soft x rays in the 50--300-eV range. An efficiency of greater than 80% is measured for energies below the Si {ital L} absorption edge. The measured efficiency is well described by a model that accounts for absorption in an oxide overlayer and recombination at the front surface of the diode. The avalanche photodiodes are shown to be significantly more sensitive compared with other detectors for pulsed sources such as a laser-produced plasma source. These results are also very encouraging for soft-x-ray/extreme-UV applications involving synchrotron radiation.{ital PACS} {ital numbers}: 29.40.Wk, 07.85.+n, 85.60.Dw.

  13. An in situ electrochemical soft X-ray spectromicroscopy investigation of Fe galvanically coupled to Au.

    PubMed

    Gianoncelli, A; Kaulich, B; Kiskinova, M; Prasciolu, M; Urzo, B D; Bozzini, B

    2011-06-01

    In this paper we report a pioneering electrochemical study of the galvanic coupling of Au and Fe in neutral aqueous solutions containing sulphate and fluoride ions, carried out by synchrotron-based in situ soft X-ray imaging and X-ray absorption microspectroscopy. The investigation was performed at the TwinMic X-ray Microscopy station at Elettra synchrotron facility combining X-ray imaging with μ-XAS with sub-micron lateral resolution. Using a purposely developed model thin-layer wet cell the morphology and chemical evolution of Fe electrodes in contact with aqueous solutions containing Na2SO4 and NaF have been investigated. The obtained results shed light on fundamental aspects regarding stability of Fe-based metallic bipolar plates in different electrochemical environments, an important issue for durability of polymer-electrolyte fuel cells. Imaging morphological features typical of the relevant electrochemical processes with chemical contrast, yields details on the spatial distribution and speciation of Fe resulting from corrosion of the Fe electrodes in the working fuel cells.

  14. X-ray microscopy of soft and hard human tissues

    SciTech Connect

    Müller, Bert Schulz, Georg Deyhle, Hans Stalder, Anja K. Ilgenstein, Bernd Holme, Margaret N. Hieber, Simone E.; Beckmann, Felix

    2016-01-28

    The simultaneous post mortem visualization of soft and hard tissues using absorption-based CT remains a challenge. If the photon energy is optimized for the visualization of hard tissue, the surrounding soft tissue components are almost X-ray transparent. Therefore, the combination with other modalities such as phase-contrast CT, magnetic resonance microscopy, and histology is essential to detect the anatomical features. The combination of the 2D and 3D data sets using sophisticated segmentation and registration tools allows for conclusions about otherwise inaccessible anatomical features essential for improved patient treatments.

  15. X-ray microscopy of soft and hard human tissues

    NASA Astrophysics Data System (ADS)

    Müller, Bert; Schulz, Georg; Deyhle, Hans; Stalder, Anja K.; Ilgenstein, Bernd; Holme, Margaret N.; Weitkamp, Timm; Beckmann, Felix; Hieber, Simone E.

    2016-01-01

    The simultaneous post mortem visualization of soft and hard tissues using absorption-based CT remains a challenge. If the photon energy is optimized for the visualization of hard tissue, the surrounding soft tissue components are almost X-ray transparent. Therefore, the combination with other modalities such as phase-contrast CT, magnetic resonance microscopy, and histology is essential to detect the anatomical features. The combination of the 2D and 3D data sets using sophisticated segmentation and registration tools allows for conclusions about otherwise inaccessible anatomical features essential for improved patient treatments.

  16. Impulsive phase of flares in soft X-ray emission

    NASA Technical Reports Server (NTRS)

    Antonucci, E.; Gabriel, A. H.; Acton, L. W.; Leibacher, J. W.; Culhane, J. L.; Rapley, C. G.; Doyle, J. G.; Machado, M. E.; Orwig, L. E.

    1982-01-01

    Observations using the bent crystal spectrometer instrument on the Solar Maximum Mission show that turbulence and blue-shifted motions are characteristic of the soft X-ray plasma during the impulsive phase of flares, and are coincident with the hard X-ray bursts observed by the hard X-ray burst spectrometer. A method for analysing the Ca XIX and Fe XXV spectra characteristic of the impulsive phase is presented. Nonthermal widths and blue-shifted components in the spectral lines of Ca XIX and Fe XXV indicate the presence of turbulent velocities exceeding 100 km/s and upward motions of 300-400 km/s. The April 10, May 9, and June 29, 1980 flares are studied. The April 10 flare has two separated footpoints bright in hard X-rays. Plasma heated to temperatures greater than ten million K rises from the footpoints. During the three minutes in which the evaporation process occurs an energy of 3.7 x 10 to the 30th ergs. This is consistent with the above figures, allowing for loss by radiation and conduction.

  17. The soft X-ray turnoff of Nova Muscae 1983

    NASA Technical Reports Server (NTRS)

    Shanley, L.; Ogelman, H.; Gallagher, J. S.; Orio, M.; Krautter, J.

    1995-01-01

    Nova GQ Muscae 1983 was detected by ROSAT as a luminous 'supersoft' X-ray source in 1992, nearly a decade after outburst. Further, this is the only classical postnova known to have maintained constant luminosity on a timescale predicted by theoretical models. Follow-up observations were made with the ROSAT position-sensitive proportional counter in 1993 January and September, and complemented with B-band photometry taken in 1993 January. By 1993 January, the X-ray count rate had declined by a factor of 17, while there was neither an appreciable decrease in the optical magnitude nor a change in the amplitude of modulation. In 1993 September the soft X-ray flux was below the ROSAT threshold limit, implying a decrease of a factor greater than or equal to 30 in the count rate. This decline can be interpreted by the turnoff of nuclear processes due to the complete consumption of the residual hydrogen-rich envelope. However, the optical luminosity of the system is not simply coupled to the X-ray luminosity (e.g., through reprocessing).

  18. Soft x-ray measurements from the PDX tokamak

    SciTech Connect

    Silver, E.H.; Bitter, M.; Brau, K.; Eames, D.; Greenberger, A.; Hill, K.W.; Meade, D.M.; Roney, W.; Sauthoff, N.R.; von Goeler, S.

    1982-05-01

    Temporally and spatially-resolved profiles of the PDX soft x-ray spectra have been measured during single tokamak pulses of circular and divertor plasmas with a recently developed pulse height analyzer. This detection system incorporates an array of five vertically displaced sets of lithium-drifted silicon detectors, each consisting of three independent channels optimized for rapid data collection in adjacent energy regions. Simultaneous measurement of x-ray emission integrated along five chords of the plasma cross section can thereby be achieved. Abel inversion of these data yields temporally-resolved radial profiles of the local electron temperature from the slope of the continuum, concentrations of high-Z impurities from the characteristic line intensities, and a measure of Z/sub eff/ from the continuum intensity. The techniques of x-ray pulse height analysis, with illustrations featuring the results from the initial PDX circular plasma experiments are discussed in detail. In addition, comparisons between circular and divertor plasmas on PDX, derived from the x-ray measurements, are also presented.

  19. The Multi-Spectral Solar Telescope Array. II - Soft X-ray/EUV reflectivity of the multilayer mirrors

    NASA Technical Reports Server (NTRS)

    Barbee, Troy W., Jr.; Weed, J. W.; Hoover, Richard B. C., Jr.; Allen, Max J.; Lindblom, Joakim F.; O'Neal, Ray H.; Kankelborg, Charles C.; Deforest, Craig E.; Paris, Elizabeth S.; Walker, Arthur B. C.

    1992-01-01

    We have developed seven compact soft X-ray/EUV (XUV) multilayer coated and two compact FUV interference film coated Cassegrain and Ritchey-Chretien telescopes for a rocket borne observatory, the Multi-Spectral Solar Telescope Array. We report here on extensive measurements of the efficiency and spectral bandpass of the XUV telescopes carried out at the Stanford Synchrotron Radiation Laboratory.

  20. The Multi-Spectral Solar Telescope Array. II - Soft X-ray/EUV reflectivity of the multilayer mirrors

    NASA Technical Reports Server (NTRS)

    Barbee, Troy W., Jr.; Weed, J. W.; Hoover, Richard B. C., Jr.; Allen, Max J.; Lindblom, Joakim F.; O'Neal, Ray H.; Kankelborg, Charles C.; Deforest, Craig E.; Paris, Elizabeth S.; Walker, Arthur B. C.

    1992-01-01

    We have developed seven compact soft X-ray/EUV (XUV) multilayer coated and two compact FUV interference film coated Cassegrain and Ritchey-Chretien telescopes for a rocket borne observatory, the Multi-Spectral Solar Telescope Array. We report here on extensive measurements of the efficiency and spectral bandpass of the XUV telescopes carried out at the Stanford Synchrotron Radiation Laboratory.

  1. IRMA-2 at SOLEIL: a set-up for magnetic and coherent scattering of polarized soft x-rays

    NASA Astrophysics Data System (ADS)

    Sacchi, M.; Popescu, H.; Gaudemer, R.; Jaouen, N.; Avila, A.; Delaunay, R.; Fortuna, F.; Maier, U.; Spezzani, C.

    2013-03-01

    We have designed, built and tested a new instrument for soft x-ray scattering experiments. IRMA-2 is a UHV set-up for elastic and coherent scattering experiments developed at the SEXTANTS beamline of the SOLEIL synchrotron. Applications will be in the field of solid state physics, with emphasis on the investigation of the magnetic properties of artificially structured materials.

  2. Soft X-ray scanning transmission X-ray microscopy (STXM) of actinide particles.

    PubMed

    Nilsson, Hans J; Tyliszczak, Tolek; Wilson, Richard E; Werme, Lars; Shuh, David K

    2005-09-01

    A descriptive account is given of our most recent research on the actinide dioxides with the Advanced Light Source Molecular Environmental Science (ALS-MES) Beamline 11.0.2 soft X-ray scanning transmission X-ray microscope (STXM) at the Lawrence Berkeley National Laboratory (LBNL). The ALS-MES STXM permits near-edge X-ray absorption fine structure (NEXAFS) and imaging with 30-nm spatial resolution. The first STXM spectromicroscopy NEXAFS spectra at the actinide 4d5/2 edges of the imaged transuranic particles, NpO2 and PuO2, have been obtained. Radiation damage induced by the STXM was observed in the investigation of a mixed oxidation state particle (Np(V,VI)) and was minimized during collection of the actual spectra at the 4d5/2 edge of the Np(V,VI) solid. A plutonium elemental map was obtained from an irregular PuO2 particle with the dimensions of 650 x 650 nm. The Pu 4d5/2 NEXAFS spectra were collected at several different locations from the PuO2 particle and were identical. A representative oxygen K-edge spectrum from UO2 was collected and resembles the oxygen K-edge from the bulk material. The unique and current performance of the ALS-MES STXM at extremely low energies (ca. 100 eV) that may permit the successful measurement of the actinide 5d edge is documented. Finally, the potential of STXM as a tool for actinide investigations is briefly discussed.

  3. Characterizing automotive fuel cell materials by soft x-ray scanning transmission x-ray microscopy

    NASA Astrophysics Data System (ADS)

    Hitchcock, A. P.; Lee, V.; Wu, J.; West, M. M.; Cooper, G.; Berejnov, V.; Soboleva, T.; Susac, D.; Stumper, J.

    2016-01-01

    Proton-Exchange Membrane Fuel Cell (PEM-FC) based engines are being developed rapidly for near-term implementation in hydrogen fueled, mass production, personal automobiles. Research is focused on understanding and controlling various degradation processes (carbon corrosion, Pt migration, cold start), and reducing cost by reducing or eliminating Pt catalyst. We are using soft X-ray scanning transmission X-ray microscopy (STXM) at the S 2p, C 1s, O 1s and F 1s edges to study a variety of issues related to optimization of PEM-FC materials for automotive applications. A method to efficiently and accurately measure perfluorosulfonic acid distributions was developed and is being used to better understand how different loadings and preparation methods affect the ionomer distribution in the cathode. Progress towards an environmental cell capable of controlling the temperature and humidity of a PEM-FC sample in the STXM is described. Methods for studying the 3D chemical structure of PEM-FC are outlined.

  4. Characterizing automotive fuel cell materials by soft x-ray scanning transmission x-ray microscopy

    SciTech Connect

    Hitchcock, A. P. Lee, V.; Wu, J.; Cooper, G.; West, M. M.; Berejnov, V.; Soboleva, T.; Susac, D.; Stumper, J.

    2016-01-28

    Proton-Exchange Membrane Fuel Cell (PEM-FC) based engines are being developed rapidly for near-term implementation in hydrogen fueled, mass production, personal automobiles. Research is focused on understanding and controlling various degradation processes (carbon corrosion, Pt migration, cold start), and reducing cost by reducing or eliminating Pt catalyst. We are using soft X-ray scanning transmission X-ray microscopy (STXM) at the S 2p, C 1s, O 1s and F 1s edges to study a variety of issues related to optimization of PEM-FC materials for automotive applications. A method to efficiently and accurately measure perfluorosulfonic acid distributions was developed and is being used to better understand how different loadings and preparation methods affect the ionomer distribution in the cathode. Progress towards an environmental cell capable of controlling the temperature and humidity of a PEM-FC sample in the STXM is described. Methods for studying the 3D chemical structure of PEM-FC are outlined.

  5. Microspectroscopic soft X-ray analysis of keratin based biofibers.

    PubMed

    Späth, Andreas; Meyer, Markus; Semmler, Sonja; Fink, Rainer H

    2015-03-01

    Scanning soft X-ray transmission microspectroscopy (STXM) and transmission electron microscopy (TEM) have been employed for a high-resolution morphological and chemical analysis of hair fibers from human, sheep and alpaca. STXM allows optimum contrast imaging of the main hair building blocks due to tuneable photon energy. Chemical similarities and deviations for the human hair building blocks as well as for the three investigated species are discussed on the basis of the local near-edge X-ray absorption fine structure (NEXAFS). The spectra of melanosomes corroborate the state-of-the-art model for the chemical structure of eumelanin. Complementary TEM micrographs reveal the occurrence of cortex sectioning in alpaca hair to some extent. A spectroscopic analysis for human hair cortex indicates low mass loss upon soft X-ray irradiation, but transformation of chemical species with decreasing amount of peptide bonds and increasing NEXAFS signal for unsaturated carbon-carbon bonds. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Soft extragalactic X-ray binaries at the Eddington Threshold

    NASA Astrophysics Data System (ADS)

    Earnshaw, Hannah M.; Roberts, Timothy P.

    2017-05-01

    The luminosity range at and just below the 1039 erg s-1 cut-off for defining ultraluminous X-ray sources (ULXs) is a little-explored regime. It none the less hosts a large number of X-ray sources, and has great potential for improving our understanding of sources with ˜Eddington accretion rates. We select a sample of four sources in this Eddington Threshold regime with good data for further study; these objects possess a variety of soft spectral shapes. We perform X-ray spectral and timing analysis on the XMM-Newton and Chandra data for these objects to gain insight into their accretion mechanisms, and also examine their optical counterparts using Hubble Space Telescope images. NGC 300 X-1 is a highly luminous and well-known example of the canonical steep power-law accretion state. M51 ULS exhibits a cool blackbody-like spectrum and is consistent with being an ultraluminous supersoft source (ULS), possibly a super-Eddington accreting object viewed at a high inclination through an optically thick outflowing wind. NGC 4395 ULX-1 and NGC 6946 ULX-1 have unusually steep power-law tails, for which we discuss a variety of possible physical mechanisms and links to similar features in Galactic microquasars, and we conclude that these sources are likely intermediate objects between the soft ultraluminous regime of ULXs and classic ULSs.

  7. Soft x-ray coherent diffraction imaging on magnetic nanostructures

    NASA Astrophysics Data System (ADS)

    Shi, Xiaowen; Lee, James; Mishra, Shrawan; Parks, Daniel; Tyliszczak, Tolek; Shapiro, David; Roy, Sujoy; Kevan, Steve; Stxm Team At Als Collaboration; Soft X-Ray Microscopy Group At Als Collaboration; Soft X-ray scattering at ALS, LBL Team

    2014-03-01

    Coherent soft X-rays diffraction imaging enable coherent magnetic resonance scattering at transition metal L-edge to be probed so that magnetic domains could be imaged with very high spatial resolution with phase contrast, reaching sub-10nm. One of the overwhelming advantages of using coherent X-rays is the ability to resolve phase contrast images with linearly polarized light with both phase and absorption contrast comparing to real-space imaging, which can only be studied with circularly polarized light with absorption contrast only. Here we report our first results on high-resolution of magnetic domains imaging of CoPd multilayer thin film with coherent soft X-ray ptychography method. We are aiming to resolve and understand magnetic domain wall structures with the highest obtainable resolution here at Advanced Light Source. In principle types of magnetic domain walls could be studied so that Neel or Bloch walls can be distinguished by imaging. This work at LBNL was supported by the Director, Office of Science, Office of Basic Energy Sciences, of the US Department of Energy (contract no. DE-AC02- 05CH11231).

  8. ASTRO-H Soft X-ray Telescope (SXT)

    NASA Astrophysics Data System (ADS)

    Soong, Yang; Serlemitsos, Peter J.; Okajima, Takashi; Hahne, Devin

    2011-09-01

    ASTRO-H is an astrophysics satellite dedicated for X-ray spectroscopic study non-dispersively and to carry out survey complementally, which will be borne out of US-Japanese collaborative effort. Among the onboard instruments there are four conically approximated Wolter-I X-ray mirrors, among which two of them are soft X-ray mirrors1, of which the energy range is from a few hundred eV to 15 keV, currently being fabricated in the X-ray Optics Lab at Goddard Space Flight Center. The focal point instruments will be a calorimeter (SXS) and a CCD camera (SXI), respectively. The reflectors of the mirror are made of heat-formed aluminum substrate of the thickness gauged of 152 μm, 229 μm, and 305 μm of the alloy 5052 H-19, followed by epoxy replication on gold-sputtered smooth Pyrex cylindrical mandrels to acquire the X-ray reflective surface. The epoxy layer is 10 μm nominal and surface gold layer of 0.2 μm. Improvements on angular response over the Astro-E1/Suzaku mirrors come from error reduction on the figure, the roundness, and the grazing angle/radius mismatching of the reflecting surface, and tighter specs and mechanical strength on supporting structure to reduce the reflector positioning and the assembly errors. In this paper, we report the results of calibration of the engineering model of SXT (EM), and project the quality of the flight mirrors.

  9. X-ray microtomography at Shanghai Synchrotron Radiation facility

    NASA Astrophysics Data System (ADS)

    Chen, Rongchang; Xie, Honglan; Deng, Biao; Du, Guohao; Ren, Yuqi; Wang, Yudan; Zhou, Guangzhao; Tan, Hai; Yang, Yiming; Xu, Liang; Hu, Tao; Li, Qiao; Feng, Binggang; Wang, Feixiang; Xiao, Tiqiao

    2016-10-01

    BL13W, an X-ray imaging beamline has been built and opened to users since May 6, 2009. More than 70 user proposals per year are granted and implemented at the beamline, with about 500 user visits/year. Up to now, X-ray microtomography (XMCT) is the dominated method for BL13W user operation, more than 70% user experiments were carried out with XMCT, covering the research fields in material science, biomedicine, physics, environmental science, archaeology and paleontology. To meet the user requirements, micro-CT imaging methods based on a variety of contrast mechanisms, including absorption, phase contrast, X-ray fluorescence, have been developed. Algorithms and related software have been developed achieve the low dose and fast data collection. Quantitative analysis to the three dimensional CT images is highly emphasized and related software for 3D information extraction with high precision and high efficiency, has been developed. Three-dimensional structure evolution has been attracting more and more attention in many scientific research fields. Two-Hertz dynamic phase contrast CT based on monochromatic SR beam was established at SSRF. The limitation of fluorescence X-ray CT from practical applications is the data-collection efficiency. The ordered-subsets expectation maximization algorithm was inducted to improve practicability of X-ray fluorescence computed tomography (XFCT), greatly. A scheme for full field XFCT was also proposed.

  10. X-ray phase-contrast tomography with a compact laser-driven synchrotron source.

    PubMed

    Eggl, Elena; Schleede, Simone; Bech, Martin; Achterhold, Klaus; Loewen, Roderick; Ruth, Ronald D; Pfeiffer, Franz

    2015-05-05

    Between X-ray tubes and large-scale synchrotron sources, a large gap in performance exists with respect to the monochromaticity and brilliance of the X-ray beam. However, due to their size and cost, large-scale synchrotrons are not available for more routine applications in small and medium-sized academic or industrial laboratories. This gap could be closed by laser-driven compact synchrotron light sources (CLS), which use an infrared (IR) laser cavity in combination with a small electron storage ring. Hard X-rays are produced through the process of inverse Compton scattering upon the intersection of the electron bunch with the focused laser beam. The produced X-ray beam is intrinsically monochromatic and highly collimated. This makes a CLS well-suited for applications of more advanced--and more challenging--X-ray imaging approaches, such as X-ray multimodal tomography. Here we present, to our knowledge, the first results of a first successful demonstration experiment in which a monochromatic X-ray beam from a CLS was used for multimodal, i.e., phase-, dark-field, and attenuation-contrast, X-ray tomography. We show results from a fluid phantom with different liquids and a biomedical application example in the form of a multimodal CT scan of a small animal (mouse, ex vivo). The results highlight particularly that quantitative multimodal CT has become feasible with laser-driven CLS, and that the results outperform more conventional approaches.

  11. X-ray phase-contrast tomography with a compact laser-driven synchrotron source

    PubMed Central

    Eggl, Elena; Schleede, Simone; Bech, Martin; Achterhold, Klaus; Loewen, Roderick; Ruth, Ronald D.; Pfeiffer, Franz

    2015-01-01

    Between X-ray tubes and large-scale synchrotron sources, a large gap in performance exists with respect to the monochromaticity and brilliance of the X-ray beam. However, due to their size and cost, large-scale synchrotrons are not available for more routine applications in small and medium-sized academic or industrial laboratories. This gap could be closed by laser-driven compact synchrotron light sources (CLS), which use an infrared (IR) laser cavity in combination with a small electron storage ring. Hard X-rays are produced through the process of inverse Compton scattering upon the intersection of the electron bunch with the focused laser beam. The produced X-ray beam is intrinsically monochromatic and highly collimated. This makes a CLS well-suited for applications of more advanced––and more challenging––X-ray imaging approaches, such as X-ray multimodal tomography. Here we present, to our knowledge, the first results of a first successful demonstration experiment in which a monochromatic X-ray beam from a CLS was used for multimodal, i.e., phase-, dark-field, and attenuation-contrast, X-ray tomography. We show results from a fluid phantom with different liquids and a biomedical application example in the form of a multimodal CT scan of a small animal (mouse, ex vivo). The results highlight particularly that quantitative multimodal CT has become feasible with laser-driven CLS, and that the results outperform more conventional approaches. PMID:25902493

  12. X-RAY IRRADIATION OF H{sub 2}O + CO ICE MIXTURES WITH SYNCHROTRON LIGHT

    SciTech Connect

    Jiménez-Escobar, A.; Ciaravella, A.; Micela, G.; Cecchi-Pestellini, C.; Chen, Y.-J.; Huang, C.-H. E-mail: ciarave@astropa.inaf.it E-mail: cecchi-pestellini@astropa.inaf.it E-mail: 101222023@cc.ncu.edu.tw

    2016-03-20

    We irradiated a (4:1) mixture of water and carbon monoxide with soft X-rays of energies up to 1.2 keV. The experiments were performed using the spherical grating monochromator beamline at National Synchrotron Radiation Research Center in Taiwan. Both monochromatic (300 and 900 eV) and broader energy fluxes (250–1200 eV) were employed. During the irradiation, the H{sub 2}O + CO mixture was ionized, excited, and fragmented, producing a number of reactive species. The composition of the ice has been monitored throughout both the irradiation and warm-up phases. We identified several products, which can be related through a plausible chemical reaction scheme. Such chemistry is initiated by the injection of energetic photoelectrons that produce multiple ionization events generating a secondary electron cascade. The results have been discussed in light of a model for protoplanetary disks around young solar-type stars.

  13. X-Ray Irradiation of H2O + CO Ice Mixtures with Synchrotron Light

    NASA Astrophysics Data System (ADS)

    Jiménez-Escobar, A.; Chen, Y.-J.; Ciaravella, A.; Huang, C.-H.; Micela, G.; Cecchi-Pestellini, C.

    2016-03-01

    We irradiated a (4:1) mixture of water and carbon monoxide with soft X-rays of energies up to 1.2 keV. The experiments were performed using the spherical grating monochromator beamline at National Synchrotron Radiation Research Center in Taiwan. Both monochromatic (300 and 900 eV) and broader energy fluxes (250-1200 eV) were employed. During the irradiation, the H2O + CO mixture was ionized, excited, and fragmented, producing a number of reactive species. The composition of the ice has been monitored throughout both the irradiation and warm-up phases. We identified several products, which can be related through a plausible chemical reaction scheme. Such chemistry is initiated by the injection of energetic photoelectrons that produce multiple ionization events generating a secondary electron cascade. The results have been discussed in light of a model for protoplanetary disks around young solar-type stars.

  14. Goldhelox: a soft x-ray solar telescope.

    PubMed

    Durfee, D S; Moody, J W; Brady, K D; Brown, C; Campbell, B; Durfee, M K; Early, D; Hansen, E; Madsen, D W; Morey, D B; Roming, P W; Savage, M B; Eastman, P F; Jensen, V

    1995-01-01

    The Goldhelox Project is the construction and use of a near-normal incidence soft x-ray robotic solar telescope by undergraduate students at Brigham Young University. Once it is completed and tested, it will be deployed from a Get-Away-Special (GAS) canister in the bay of a space shuttle. It will image the sun at a wavelength of 171-181Å with a time resolution of 1 sec and a spatial resolution of 2.5 arcsec. The observational bandpass was chosen to image x-rays from highly ionized coronal Fe lines. The data will be an aid in better understanding the beginning phases of solar flares and how flaring relates to the physics of the corona-chromosphere transition region. Goldhelox is tentatively scheduled to fly on a space shuttle sometime in 1995 or 1996. This paper outlines the project goals, basic instrument design, and the unique aspects of making this an undergraduate endeavor.

  15. New Developments in Femtosecond Soft X-ray Spectroscopy

    SciTech Connect

    Erko, A.; Firsov, A.; Holldack, K.

    2010-06-23

    Recent instrumentation developments in X-ray spectroscopy for ultra-fast time-resolved measurements with soft X-rays done in HZB Berlin during the last years are described. The significant performance improvements achieved this way are based on Fresnel diffraction from structures being fabricated on a surface of a total externally reflecting mirror. The first type of this spectrometer, an off-axis reflection zone plate, has been implemented at the BESSY Femtoslicing setup and shows on the order of 20 times higher flux in the focal plane compared to the classical grating monochromator beamline. It has proven to serve very precise experiments with a time resolution down to 100 fs on magnetic materials after optical laser pulse excitation.

  16. Soft x-ray emission from classical novae in outburst

    SciTech Connect

    Starrfield, S. Arizona State Univ., Tempe, AZ . Dept. of Physics and Astronomy); Truran, J.W. . Dept. of Astronomy); Sparks, W.M. ); Krautter, J. ); MacDonald, J. . Dept. of Physics and Ast

    1989-01-01

    Theoretical modeling of novae in outburst predicts that they should be active emitters of radiation at soft x-ray wavelengths twice during their outburst. The first time occurs very early in the outburst when only a very sensitive all sky survey will be able to detect them. This period lasts only a few hours for the very fastest novae. They again become bright in x-rays late in the outburst when the remnant object becomes very hot and is still luminous. Both simulations and observations show that novae can remain very hot for months to years. It is important to observe them at these late times because a measurement both of the flux and temperature can provide information about the mass of the white dwarf, the turn-off time scale, and the energy budget of the outburst. 8 refs., 2 figs.

  17. Soft X-ray spectroscopy of solar flares - An overview

    NASA Technical Reports Server (NTRS)

    Doschek, G. A.

    1990-01-01

    An overview of the current status of high spectral resolution soft X-ray observations of solar flares is given. The review concentrates primarily on recent results and interpretations of results obtained from orbiting Bragg crystal spectrometers flow during the last solar maximum on the US DoD P78-1 spacecraft, the NASA SMM, and the ISAS Hinotori spacecraft. Results and several key issues regarding interpretation of the spectra are presented. Specifically, the dynamics of coronal flare plasmas as revealed by X-ray line profiles and wavelength shifts are discussed. Recent results concerning the theory of chromospheric evaporation are given. The temperature of coronal flare plasma is discussed within the context of a differential mission measure. Results concerning electron density measurements, nonequilibrium processes, and relative element abundances are also reviewed.

  18. Soft X-ray spectroscopy of solar flares - an overview

    NASA Astrophysics Data System (ADS)

    Doschek, G. A.

    1990-06-01

    An overview of the current status of high spectral resolution soft X-ray observations of solar flares is given. The review concentrates primarily on recent results and interpretations of results obtained from orbiting Bragg crystal spectrometers flow during the last solar maximum on the US DoD P78-1 spacecraft, the NASA SMM, and the ISAS Hinotori spacecraft. Results and several key issues regarding interpretation of the spectra are presented. Specifically, the dynamics of coronal flare plasmas as revealed by X-ray line profiles and wavelength shifts are discussed. Recent results concerning the theory of chromospheric evaporation are given. The temperature of coronal flare plasma is discussed within the context of a differential mission measure. Results concerning electron density measurements, nonequilibrium processes, and relative element abundances are also reviewed.

  19. Soft x-ray spectroscopy of the Vela supernova remnant

    NASA Astrophysics Data System (ADS)

    Zeiger, Benjamin R.

    The CODEX sounding rocket payload was designed and flown to significantly improve spectral resolution of the Vela supernova remnant (SNR) in the soft x-ray (0.1--1.0 keV) bandpass. High spectral resolution (E/Delta E > 40) across its 3.25° x 3.25° field of view would disentangle thermal emission from nonthermal or line emission components to constrain the age when SNRs stop emitting nonthermal x-rays. Relatively recent observations have found significant nonthermal emission from remnants up to several kyr old, but CODEX encountered concurrent problems of higher noise and lower signal than expected, leaving the thermal versus nonthermal question unanswered in the 11 kyr-old Vela SNR. This thesis covers the motivation, design, and post-flight analysis of the CODEX instrument and data from its flight.

  20. Diagnostics for an XUV/soft x-ray laser

    SciTech Connect

    Kauffman, R.L.; Matthews, D.L.; Ceglio, N.; Medecki, H.

    1984-03-03

    We have begun investigating the production of an XUV/soft x-ray laser, using our high-powered glass lasers as drivers. A major diagnostic for lasing is the measure of the absolute power produced in the lasing line. I have developed a spectrograph to time-resolved lasing lines in the energy range from 50 eV to greater than 200 eV. the spectrograph combines a transmission grating and x-ray streak camera to produce a flat field instrument. A cylindrical mirror is used in front of the grating to image the source and act as a collecting optic. The efficiency of the components is calibrated so that absolute intensities can be measured. I will compare the performance of this instrument with reflection grating systems. I will also discuss planned improvements to the system which should increase total throughput, image quality, and resolving power.

  1. Thermal management of next-generation contact-cooled synchrotron x-ray mirrors

    SciTech Connect

    Khounsary, A.

    1999-10-29

    In the past decade, several third-generation synchrotrons x-ray sources have been constructed and commissioned around the world. Many of the major problems in the development and design of the optical components capable of handling the extremely high heat loads of the generated x-ray beams have been resolved. It is expected, however, that in the next few years even more powerful x-ray beams will be produced at these facilities, for example, by increasing the particle beam current. In this paper, the design of a next generation of synchrotron x-ray mirrors is discussed. The author shows that the design of contact-cooled mirrors capable of handing x-ray beam heat fluxes in excess of 500 W/mm{sup 2} - or more than three times the present level - is well within reach, and the limiting factor is the thermal stress rather then thermally induced slope error.

  2. X-ray synchrotron dual energy imaging for material specific study

    NASA Astrophysics Data System (ADS)

    Singh, B.; Agrawal, A. K.; Kashyap, Y. S.; Gadkari, S. C.

    2017-05-01

    X-ray imaging techniques, in general, are used to study the internal structures of an object non-destructively such as anatomy, imperfections, cracks and voids whereas insensitive to spatial distribution of different element or elemental compositions of the object. With the development of advance bright X-ray synchrotron sources and accurate energy tunability using high resolution crystal monochromator, detection of elemental distribution in an object became possible. Quantitative small concentrations with enhance contrast can be detected fast in X-ray synchrotron based dual energy imaging, in comparison to conventional X-ray lab based techniques. We report here the experimental setup, image acquisition and image processing for the dual energy X-ray imaging (DEI) technique to retrieve the spatial distribution of different elements in the object.

  3. Magnetic imaging with polarized soft x-rays

    NASA Astrophysics Data System (ADS)

    Fischer, Peter

    2017-08-01

    Properties, behavior, and functionalities of magnetic materials are largely determined by microscopic spin textures, particularly their formation into domains, their coupling mechanisms and their dynamic behavior. Advanced characterization tools are prerequisite to fundamentally understand magnetic materials and control spins for novel magnetic applications. Magnetic microscopies allow us to image directly the static and dynamic features of the relevant microscopic magnetization structures in advanced magnetic materials and thus provide detailed and direct insight into underlying physical phenomena. A large variety of magnetic imaging techniques has become available with particular strengths but also certain limitations. Essential features of magnetic microscopies are a high spatial resolution down into the nanometer regime, as this is the fundamental length scale of magnetic exchange interaction and the ultimate length scale in advanced magnetic technologies; magnetic and elemental sensitivity with quantitative capabilities, as the properties of advanced magnetic materials can be tailored by combining various magnetic elements and their magnetic moments; high temporal resolution from the ns to the fs regime to understand the associated spin dynamic processes and the functionality in magnetic devices; tomographic capabilities with nm resolution as new directions in nanoscience and technologies are moving into 3 dim arrangements of spin structures; and interfacial sensitivity as novel ways to control spins harness either the coupling across interfaces in multilayered structures or utilize non-collinear spin arrangements, which often occur from symmetry breaking at surfaces and interfaces. The unique properties of polarized soft x-rays, their abundancy and specific interaction with magnetic materials in form of dichroism effects have triggered the development of various magnetic x-ray imaging techniques. This review will provide an overview of the current state

  4. Disentangling AGN and Star Formation in Soft X-Rays

    NASA Technical Reports Server (NTRS)

    LaMassa, Stephanie M.; Heckman, T. M.; Ptak, A.

    2012-01-01

    We have explored the interplay of star formation and active galactic nucleus (AGN) activity in soft X-rays (0.5-2 keV) in two samples of Seyfert 2 galaxies (Sy2s). Using a combination of low-resolution CCD spectra from Chandra and XMM-Newton, we modeled the soft emission of 34 Sy2s using power-law and thermal models. For the 11 sources with high signal-to-noise Chandra imaging of the diffuse host galaxy emission, we estimate the luminosity due to star formation by removing the AGN, fitting the residual emission. The AGN and star formation contributions to the soft X-ray luminosity (i.e., L(sub x,AGN) and L(sub x,SF)) for the remaining 24 Sy2s were estimated from the power-law and thermal luminosities derived from spectral fitting. These luminosities were scaled based on a template derived from XSINGS analysis of normal star-forming galaxies. To account for errors in the luminosities derived from spectral fitting and the spread in the scaling factor, we estimated L(sub x,AGN) and L(sub x,SF))from Monte Carlo simulations. These simulated luminosities agree with L(sub x,AGN) and L(sub x,SF) derived from Chandra imaging analysis within a 3sigma confidence level. Using the infrared [Ne ii]12.8 micron and [O iv]26 micron lines as a proxy of star formation and AGN activity, respectively, we independently disentangle the contributions of these two processes to the total soft X-ray emission. This decomposition generally agrees with L(sub x,SF) and L(sub x,AGN) at the 3 sigma level. In the absence of resolvable nuclear emission, our decomposition method provides a reasonable estimate of emission due to star formation in galaxies hosting type 2 AGNs.

  5. Development and applications of an epifluorescence module for synchrotron x-ray fluorescence microprobe imaging

    SciTech Connect

    Miller, Lisa M.; Smith, Randy J.; Ruppel, Meghan E.; Ott, Cassandra H.; Lanzirotti, Antonio

    2005-06-15

    Synchrotron x-ray fluorescence (XRF) microprobe is a valuable analysis tool for imaging trace element composition in situ at a resolution of a few microns. Frequently, epifluorescence microscopy is beneficial for identifying the region of interest. To date, combining epifluorescence microscopy with x-ray microprobe has involved analyses with two different microscopes. We report the development of an epifluorescence module that is integrated into a synchrotron XRF microprobe beamline, such that visible fluorescence from a sample can be viewed while collecting x-ray microprobe images simultaneously. This unique combination has been used to identify metal accumulation in Alzheimer's disease plaques and the mineral distribution in geological samples. The flexibility of this accessory permits its use on almost any synchrotron x-ray fluorescence microprobe beamline and applications in many fields of science can benefit from this technology.

  6. Heliospheric X-Rays and the 1/4 keV Soft X-Ray Background Map

    NASA Astrophysics Data System (ADS)

    Robertson, I. P.; Cravens, T. E.; Snowden, S. L.

    2003-12-01

    X-rays are generated throughout the heliosphere as a consequence of charge transfer collisions between heavy solar wind ions and interstellar neutrals. The high charge state solar wind ions resulting from these collisions are left in highly excited states and emit extreme ultraviolet or soft x-ray photons. X-rays are also generated because of charge transfer collisions with neutral hydrogen in the Earth's geocorona. Our model simulates this charge transfer mechanism. It uses the Fahr hot model to determine spatial variations of interstellar helium and hydrogen densities. It also uses published terrestrial exospheric hydrogen distributions and solar wind speed, density and temperature distributions to determine x-ray intensities due to charge transfer with geocoronal hydrogen. We used the same viewing conditions as Snowden [1995] for the 1/4 keV channel soft x-ray background map in galactic coordinates, and produce an analogous heliospheric/geocoronal x-ray intensity map. Our preliminary conclusion is that roughly 50% of the total background soft x-ray intensity in the galactic plane and 25% at high galactic latitudes can be attributed to the charge transfer process operating within the solar system, with the remaining emission coming from outside our heliosphere.

  7. 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

  8. 3D nanoscale imaging of biological samples with laboratory-based soft X-ray sources

    NASA Astrophysics Data System (ADS)

    Dehlinger, Aurélie; Blechschmidt, Anne; Grötzsch, Daniel; Jung, Robert; Kanngießer, Birgit; Seim, Christian; Stiel, Holger

    2015-09-01

    In microscopy, where the theoretical resolution limit depends on the wavelength of the probing light, radiation in the soft X-ray regime can be used to analyze samples that cannot be resolved with visible light microscopes. In the case of soft X-ray microscopy in the water-window, the energy range of the radiation lies between the absorption edges of carbon (at 284 eV, 4.36 nm) and oxygen (543 eV, 2.34 nm). As a result, carbon-based structures, such as biological samples, posses a strong absorption, whereas e.g. water is more transparent to this radiation. Microscopy in the water-window, therefore, allows the structural investigation of aqueous samples with resolutions of a few tens of nanometers and a penetration depth of up to 10μm. The development of highly brilliant laser-produced plasma-sources has enabled the transfer of Xray microscopy, that was formerly bound to synchrotron sources, to the laboratory, which opens the access of this method to a broader scientific community. The Laboratory Transmission X-ray Microscope at the Berlin Laboratory for innovative X-ray technologies (BLiX) runs with a laser produced nitrogen plasma that emits radiation in the soft X-ray regime. The mentioned high penetration depth can be exploited to analyze biological samples in their natural state and with several projection angles. The obtained tomogram is the key to a more precise and global analysis of samples originating from various fields of life science.

  9. A tunable X-ray microprobe using synchrotron radiation

    NASA Astrophysics Data System (ADS)

    Wu, Y.; Thompson, A. C.; Underwood, J. H.; Giauque, R. D.; Chapman, K.; Rivers, M. L.; Jones, K. W.

    1990-05-01

    We describe an X-ray microprobe using multilayer mirrors. Previously, we have demonstrated a Kirkpatrick-Baez type focusing system working at both 8 and 10 keV and successfully applied it to a variety of applications, including the determination of elemental contents in fluid inclusions. In this paper, we show that the usable excitation energy for this microprobe is not restricted to between 8 and 10 keV, and furthermore that it can be simply tuned in operation. A 10 keV X-ray fluorescence microprobe can be used to measure the concentration of the elements from K ( Z = 19) to Zn ( Z = 30) using K X-ray lines, and from Cd ( Z = 48) to Er ( Z = 68) using L X-ray lines. There are a number of geologically important elements in the gap between Ga ( Z = 31) and Ag ( Z = 47) and with Z > 68. In order to cover this range, a higher excitation energy is required. On the other hand, for samples that contain major elements with absorption edges lower than the excitation energy, it would be hard to detect other minor elements because of the strong signal from the major elements and the background they produce. In this case, a tunable X-ray source can be used to avoid the excitation of the major elements. We demonstrate that, with the existing setup, it is possible to tune the excitation energy from 6 to 14 keV. In this range, the intensity does not decrease by more than one order of magnitude. As an illustrative example, a geological sample was examined using two different excitation energies to show the advantage of a tunable source. Finally, we discuss the possibility of further extension of the excitation energy range as well as the possibility of improving the intensity.

  10. A tunable x ray microprobe using synchrotron radiation

    NASA Astrophysics Data System (ADS)

    Wu, Y.; Thompson, A. C.; Underwood, J. H.; Giauque, R. D.; Chapman, K.; Rivers, M. L.; Jones, K. W.

    1989-08-01

    We describe an x ray microprobe using multilayer mirrors. Previously, we had demonstrated a Kirkpatrick-Baez type focusing system working at both 8 and 10 keV and successfully applied it to a variety of applications, including the determination of elemental contents in fluid inclusions. In this paper, we show that the usable excitation energy for this microprobe is not restricted to between 8 and 10 keV, and furthermore, it can be simply tuned in operation. A 10-keV x ray fluorescence microprobe can be used to measure the concentration of the elements from potassium (Z = 19) to zinc (Z = 30) using K x ray lines, and from cadmium (Z = 48) to erbium (Z = 68) using L x-ray lines. There are a number of geologically important elements in the gap between gallium (Z = 31) and silver (Z = 47) and also with Z greater than 68. In order to cover this range, a higher excitation energy is required. On the other hand, for samples that contain major elements with absorption edges lower than the excitation energy, it would be hard to detect other mirror elements because of the strong signal from the major elements and the background they produce. In this case, a tunable x ray source can be used to avoid the excitation of the major elements. We demonstrate that, with the existing setup, it is possible to tune the excitation energy from 6 keV to 14 keV, in this range, the intensity does not decrease by more than one order of magnitude. As an illustration, a geological sample was examined by using two different excitation energies to show the advantage of a tunable source. Finally, we discuss the possibility of further extension of the excitation energy range as well as the possibility of improving the intensity.

  11. High-resolution visualization of airspace structures in intact mice via synchrotron phase-contrast X-ray imaging (PCXI).

    PubMed

    Parsons, David W; Morgan, Kaye; Donnelley, Martin; Fouras, Andreas; Crosbie, Jeffrey; Williams, Ivan; Boucher, Richard C; Uesugi, Kentaro; Yagi, Naoto; Siu, Karen K W

    2008-08-01

    Anatomical visualization of airspace-containing organs in intact small animals has been limited by the resolution and contrast available from current imaging methods such as X-ray, micro-computed tomography and magnetic resonance imaging. Determining structural relationships and detailed anatomy has therefore relied on suitable fixation, sectioning and histological processing. More complex and informative analyses such as orthogonal views of an organ and three-dimensional structure visualizations have required different animals and image sets, laboriously processed to gather this complementary structural information. Precise three-dimensional anatomical views have always been difficult to achieve in small animals. Here we report the ability of phase-contrast synchrotron X-ray imaging to provide detailed two- and three-dimensional visualization of airspace organ structures in intact animals. Using sub-micrometre square pixel charge-coupled device array detectors, the structure and anatomy of hard and soft tissues, and of airspaces, is readily available using phase-contrast synchrotron X-ray imaging. Moreover, software-controlled volume-reconstructions of tomographic images not only provide unsurpassed image clarity and detail, but also selectable anatomical views that cannot be obtained with established histological techniques. The morphology and structure of nasal and lung airways and the middle ear are illustrated in intact mice, using two- and three-dimensional representations. The utility of phase-contrast synchrotron X-ray imaging for noninvasively localizing objects implanted within airspaces, and the detection of gas bubbles transiting live airways, are other novel features of this visualization methodology. The coupling of phase-contrast synchrotron X-ray imaging technology with software-based reconstruction techniques holds promise for novel and high-resolution non-invasive examination of airspace anatomy in small animal models.

  12. High-resolution visualization of airspace structures in intact mice via synchrotron phase-contrast X-ray imaging (PCXI)

    PubMed Central

    Parsons, David W; Morgan, Kaye; Donnelley, Martin; Fouras, Andreas; Crosbie, Jeffrey; Williams, Ivan; Boucher, Richard C; Uesugi, Kentaro; Yagi, Naoto; Siu, Karen K W

    2008-01-01

    Anatomical visualization of airspace-containing organs in intact small animals has been limited by the resolution and contrast available from current imaging methods such as X-ray, micro-computed tomography and magnetic resonance imaging. Determining structural relationships and detailed anatomy has therefore relied on suitable fixation, sectioning and histological processing. More complex and informative analyses such as orthogonal views of an organ and three-dimensional structure visualizations have required different animals and image sets, laboriously processed to gather this complementary structural information. Precise three-dimensional anatomical views have always been difficult to achieve in small animals. Here we report the ability of phase-contrast synchrotron X-ray imaging to provide detailed two- and three-dimensional visualization of airspace organ structures in intact animals. Using sub-micrometre square pixel charge-coupled device array detectors, the structure and anatomy of hard and soft tissues, and of airspaces, is readily available using phase-contrast synchrotron X-ray imaging. Moreover, software-controlled volume-reconstructions of tomographic images not only provide unsurpassed image clarity and detail, but also selectable anatomical views that cannot be obtained with established histological techniques. The morphology and structure of nasal and lung airways and the middle ear are illustrated in intact mice, using two- and three-dimensional representations. The utility of phase-contrast synchrotron X-ray imaging for non-invasively localizing objects implanted within airspaces, and the detection of gas bubbles transiting live airways, are other novel features of this visualization methodology. The coupling of phase-contrast synchrotron X-ray imaging technology with software-based reconstruction techniques holds promise for novel and high-resolution non-invasive examination of airspace anatomy in small animal models. PMID:19172736

  13. Determination of impurities in graphite using synchrotron radiation based X-ray fluorescence spectrometry.

    PubMed

    Ghosh, M; Swain, K K; Remya Devi, P S; Chavan, T A; Singh, A K; Tiwari, M K; Verma, R

    2017-10-01

    Determination of impurities namely Ca, Mn, Fe, Ni, Zn, Sr and Pb in graphite by energy dispersive X-ray fluorescence spectrometry is described using microfocused synchrotron radiation. The internal standard and standard addition methodologies were adopted for quantification and the results were compared with tube-based X-ray fluorescence spectrometry. Analysis of the results by the F and t-tests revealed their statistical equivalence. Synchrotron measurements improved the detection limits by an order of magnitude compared to the tube based technique. Cr and Zr, which were below the quantification limit in tube based technique, were also quantified by synchrotron based technique. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Proton induced quasi-monochromatic x-ray beams for soft x-ray spectroscopy studies and selective x-ray fluorescence analysis

    SciTech Connect

    Sokaras, D.; Zarkadas, Ch.; Fliegauf, R.; Beckhoff, B.; Karydas, A. G.

    2012-12-15

    We present the analytical features and performance of an x-ray spectroscopy end station of moderate energy resolution operating with proton-induced quasi-monochromatic x-ray beams. The apparatus was designed, installed and operated at the 5.5 MV Tandem VdG Accelerator Laboratory of the Institute of Nuclear Physics, N.C.S.R. 'Demokritos,' Athens. The setup includes a two-level ultrahigh vacuum chamber that hosts in the lower level up to six primary targets in a rotatable holder; there, the irradiation of pure element materials-used as primary targets-with few-MeV high current ({approx}{mu}A) proton beams produces intense quasi-monochromatic x-ray beams of selectable energy. In the chamber's upper level, a six-position rotatable sample holder hosts the targets considered for x-ray spectroscopy studies. The proton-induced x-ray beam, after proper collimation, is guided to the sample position whereas various filters can be also inserted along the beam's path to eliminate the backscattered protons or/and to absorb selectively components of the x-ray beam. The apparatus incorporates an ultrathin window Si(Li) spectrometer (FWHM 136 eV at 5.89 keV) coupled with low-noise electronics capable of efficiently detecting photons down to carbon K{alpha}. Exemplary soft x-ray spectroscopy studies and results of selective x-ray fluorescence analysis are presented.

  15. Development of a differential pumping system for soft X-ray beamlines for windowless experiments under normal atmospheric conditions.

    PubMed

    Tamenori, Y

    2010-03-01

    A novel design for a differential pumping system has been investigated. This system allows windowless experiments in a soft X-ray beamline under normal atmospheric conditions. The new design consists of an aperture-based four-stage differential pumping system, based on a simple model calculation. A prototype system with a total length of 600 mm was constructed to confirm the validity of the design concept. Relatively short conductance-limiting components allow easy installation and alignment of the system on a synchrotron beamline. The fabricated system was installed on a beamline to test the transmission of soft X-rays through atmospheric helium.

  16. Comparison of a CCD and an APS for soft X-ray diffraction

    NASA Astrophysics Data System (ADS)

    Stewart, Graeme; Bates, R.; Blue, A.; Clark, A.; Dhesi, S. S.; Maneuski, D.; Marchal, J.; Steadman, P.; Tartoni, N.; Turchetta, R.

    2011-12-01

    We compare a new CMOS Active Pixel Sensor (APS) to a Princeton Instruments PIXIS-XO: 2048B Charge Coupled Device (CCD) with soft X-rays tested in a synchrotron beam line at the Diamond Light Source (DLS). Despite CCDs being established in the field of scientific imaging, APS are an innovative technology that offers advantages over CCDs. These include faster readout, higher operational temperature, in-pixel electronics for advanced image processing and reduced manufacturing cost. The APS employed was the Vanilla sensor designed by the MI3 collaboration and funded by an RCUK Basic technology grant. This sensor has 520 x 520 square pixels, of size 25 μm on each side. The sensor can operate at a full frame readout of up to 20 Hz. The sensor had been back-thinned, to the epitaxial layer. This was the first time that a back-thinned APS had been demonstrated at a beam line at DLS. In the synchrotron experiment soft X-rays with an energy of approximately 708 eV were used to produce a diffraction pattern from a permalloy sample. The pattern was imaged at a range of integration times with both sensors. The CCD had to be operated at a temperature of -55°C whereas the Vanilla was operated over a temperature range from 20°C to -10°C. We show that the APS detector can operate with frame rates up to two hundred times faster than the CCD, without excessive degradation of image quality. The signal to noise of the APS is shown to be the same as that of the CCD at identical integration times and the response is shown to be linear, with no charge blooming effects. The experiment has allowed a direct comparison of back thinned APS and CCDs in a real soft x-ray synchrotron experiment.

  17. Recent upgrades to MST's soft-x-ray spectroscopy diagnostic

    NASA Astrophysics Data System (ADS)

    Pandya, M. D.; Scherer, A. C.; Clark, J.; Dubois, A. M.; Almagri, A. F.; Chapman, B. E.

    2016-10-01

    In MST RFP plasmas, electron energization during tearing mode reconnection events was recently observed via soft-x-ray (sxr) emission. X-ray measurements from 3-25 keV during these short-lived (< 100 μs) events were achieved with a detector consisting of an avalanche photodiode and a 20 ns Gaussian shaping amplifier (GSA) whose output was digitized at 500 MHz. A radially resolved measurement of x-ray emission from 2-10 keV can also be made with an existing array of six Amptek XR-100CR sxr detectors, each comprised of a Si photodiode, a charge-sensitive preamplifier, a thermoelectric cooler, and a Cremat GSA CR-200-500ns having a pulse FWHM of about 1200 ns. One upgrade to this system entails a CR-200-25ns GSA which will reduce the FWHM to 60 ns. The digitization rate is also increased from 60 MHz to 240 MHz, sufficient to resolve a 60 ns Gaussian pulse. The upgrade will also incorporate improved shielding from IGBT switching noise arising from MST's Bt and Bp programmable power supplies. Housing the detector assembly within Compac-SRF-series enclosures attenuates noise at 20 MHz by 80 dB. Initial measurements will be presented. Work supported by US DOE.

  18. Suborbital Soft X-Ray Spectroscopy with Gaseous Electron Multipliers

    NASA Astrophysics Data System (ADS)

    Rogers, Thomas D.

    This thesis consists of the design, fabrication, and launch of a sounding rocket payload to observe the spectrum of the soft X-ray emission (0.1-1 keV) from the Cygnus Loop supernova remnant. This instrument, designated the Off-plane Grating Rocket for Extended Source Spectroscopy (OGRESS), was launched from White Sands Missile Range on May 2nd, 2015. The X-ray spectrograph incorporated a wire-grid focuser feeding an array of gratings in the extreme off-plane mount which dispersed the spectrum onto Gaseous Electron Multiplier (GEM) detectors. The gain characteristics of OGRESS's GEM detectors were fully characterized with respect to applied voltage and internal gas pressure, allowing operational settings to be optimized. The GEMs were optimized to operate below laboratory atmospheric pressure, allowing lower applied voltages, thus reducing the risk of both electrical arcing and tearing of the thin detector windows. The instrument recorded 388 seconds of data and found highly uniform count distributions over both detector faces, in sharp contrast to the expected thermal line spectrum. This signal is attributed to X-ray fluorescence lines generated inside the spectrograph. The radiation is produced when thermal ionospheric particles are accelerated into the interior walls of the spectrograph by the high voltages of the detector windows. A fluorescence model was found to fit the flight data better than modeled supernova spectra. Post-flight testing and analysis revealed that electrons produce distinct signal on the detectors which can also be successfully modeled as fluorescence emission.

  19. Soft x-ray microscope using Fourier transform holography

    SciTech Connect

    McNulty, I.; Kirz, J.; Jacobsen, C.; Anderson, E.; Howells, M.R.; Rarback, H. . Dept. of Physics; Lawrence Berkeley Lab., CA; Brookhaven National Lab., Upton, NY )

    1989-01-01

    A Fourier transform holographic microscope with an anticipated resolution of better than 100 nm has been built. Extensive testing of the apparatus has begun. Preliminary results include the recording of interference fringes using 3.6 nm x-rays. The microscope employs a charge-coupled device (CCD) detector array of 576 {times} 384 elements. The system is illuminated by soft x-rays from a high brightness undulator. The reference point source is formed by a Fresnel zone plate with a finest outer zone width of 50 nm. Sufficient temporal coherence for hologram formation is obtained by a spherical grating monochromator. The x-ray hologram intensities at the recording plane are to be collected, digitized and reconstructed by computer. Data acquisition is under CAMAC control, while image display and off-line processing takes place on a VAX graphics workstation. Computational models of Fourier transform hologram synthesis, and reconstruction in the presence of noise, have demonstrated the feasibility of numerical methods in two dimensions, and that three-dimensional information is potentially recoverable. 13 refs., 3 figs.

  20. Synoptic IPS and Yohkoh soft X-ray observations

    NASA Technical Reports Server (NTRS)

    Hick, P.; Jackson, B. V.; Rappoport, S.; Woan, G.; Slater, G.; Strong, K.; Uchida, Y.

    1995-01-01

    Interplanetary scintillation measurements of the disturbance factor, g, from October 1991 to October 1992 are used to construct synoptic Carrington maps. These maps, which show the structure of the quiet solar wind, are compared with X-ray Carrington maps from the Yohkoh Soft X-ray Telescope (SXT) instrument. For the period studied the global structure outlined by (weakly) enhanced g-values apparent in the interplanetary scintillation (IPS) maps tend to match the active regions (as shown in the X-ray maps) significantly better than the heliospheric current sheet. Contrary to traditional opinion, which views active regions as magnetically closed structures that do not have any significant impact on the solar wind flow, our results suggest that density fluctuations in the solar wind are significantly enhanced over active regions. These results support the suggestion by Uchida et al. (1992), based on Yohkoh observations of expanding active regions, that active regions play a role in feeding mass into the quiet solar wind.

  1. OSO-8 soft X-ray wheel experiment: Data analysis

    NASA Technical Reports Server (NTRS)

    Kraushaar, W. L.

    1982-01-01

    The soft X-ray experiment hardware and its operation are described. The device included six X-ray proportional counters, two of which, numbers 1 and 4, were pressurized with on-board methane gas supplies. Number 4 developed an excessive leak rate early in the mission and was turned off on 1975 day number 282 except for brief (typically 2-hour) periods up to day 585 after which it as left off. Counter 1 worked satisfactorily until 1975 day number 1095 (January 1, 1978) at which time the on-board methane supply was depleted. The other four counters were sealed and all except number 3 worked satisfactorily throughout the mission which terminated with permanent satellie shut-down on day 1369. This was the first large area thin-window, gas-flow X-ray detector to be flown in orbit. The background problems were severe and consumed a very large portion of the data analysis effort. These background problems were associated with the Earth's trapped electron belts.

  2. The Astro-H Soft X-Ray Mirror

    NASA Technical Reports Server (NTRS)

    Robinson, David; Okajima, Takashi; Serlemitsos, Peter; Soong, Yang

    2012-01-01

    The Astro-H is led by the Japanese Space Agency (JAXA) in collaboration with many other institutions including the NASA Goddard Space Flight Center. Goddard's contributions include two soft X-ray telescopes (SXTs). The telescopes have an effective area of 562 square cm at 1 keV and 425 square cm at 6 keV with an image quality requirement of 1.7 arc-minutes half power diameter (HPD). The engineering model has demonstrated 1.1 arc-minutes HPD error. The design of the SXT is based on the successful Suzaku mission mirrors with some enhancements to improve the image quality. Two major enhancements are bonding the X-ray mirror foils to alignment bars instead of allowing the mirrors to float, and fabricating alignment bars with grooves within 5 microns of accuracy. An engineering model SXT was recently built and subjected to several tests including vibration, thermal, and X-ray performance in a beamline. Several lessons were learned during this testing that will be incorporated in the flight design. Test results and optical performance are discussed, along with a description of the design of the SXT.

  3. The Astro-H Soft X-ray Spectrometer (SXS)

    SciTech Connect

    Porter, F. Scott; Kelley, Richard L.; Kilbourne, Caroline A.; Fujimoto, Ryuichi; Mitsuda, Kazuhiasa; Ohashi, Takaya

    2009-12-16

    The Soft-X-ray Spectrometer (SXS) is a high spectral resolution, cryogenic x-ray spectrometer that will fly on the Japan/U.S. Astro-H observatory in 2014. The SXS is composed of a 36 pixel, imaging, x-ray calorimeter array that will operate at 0.05 K utilizing a 2-stage adiabatic demagnetization refrigerator and a redundant pre-cooler design using both a 40 liter liquid helium tank and a 1.7 K Joule-Thomson (JT) cryocooler. Additional redundant Stirling cycle coolers provide pre-cooling for the (JT) and cool the outer thermal shields for the JT and the helium tank. The detector system, while similar to that flown on Suzaku, is composed of larger 0.81x0.81mm pixels, but has significantly better performance, currently predicted to be better than 4 eV FWHM at 6 keV with 95% quantum efficiency. This instrument is the result of a close collaboration between many institutions in the U.S. and Japan over the last 25 years. Here we will present an overview of the SXS instrument, the SXS cooling system, and recent laboratory improvements to the detector system.0.

  4. Soft X-ray Charged Piezoelectret for Kinetic Energy Harvesting

    NASA Astrophysics Data System (ADS)

    Lu, J.; Cho, HJ; Suzuki, Y.

    2016-11-01

    Piezoelectret polymer attracts much attention for its high piezoelectric coefficient. Multilayered piezoelectret structures are often charged with corona discharge, but it is difficult to get high surface charge density. To address this issue, a multilayered piezoelectret structure with embedded electrode is proposed, which can be efficiently poled with soft X-ray charging. With the aid of embedded electrodes, the bias voltage is directly applied to each unit cell, rather than divided and distributed to multiple layers. With an early PTFE-based prototype, output power of 0.5 μJ has been obtained for 0.3 mm displacement in 0.2 s.

  5. Imaging and nondispersive spectroscopy of soft X rays using a laboratory X-ray charge-coupled-device system

    NASA Technical Reports Server (NTRS)

    Luppino, Gerard A.; Doty, John P.; Ricker, George R.; Vallerga, John V.; Ceglio, Natale M.

    1987-01-01

    This paper describes the design and performance of a laboratory instrument for imaging and nondispersive spectroscopy of soft X-rays (300 eV to 10 keV) utilizing a virtual-phase CCD. This instrument has achieved a spatial resolution of 22 microns (limited by pixel size) with an overall array area of 584 x 390 pixels. It has achieved an energy resolution of about 140 eV FWHM for single-pixel Fe-55 X-ray events (5.9 keV) with the CCD operated at -30 C. The CCD has been operated in photon-counting mode at room temperature, and X-ray spectra with an energy resolution of about 450 eV at 5.9 keV have been obtained. The low energy X-ray sensitivity of the CCD also has been demonstrated by detecting carbon K-alpha X-rays (277eV).

  6. Observing soft X-ray line emission from the interstellar medium with X-ray calorimeter on a sounding rocket

    NASA Technical Reports Server (NTRS)

    Zhang, J.; Edwards, B.; Juda, M.; Mccammon, D.; Skinner, M.; Kelley, R.; Moseley, H.; Schoelkopf, R.; Szymkowiak, A.

    1990-01-01

    For an X-ray calorimeter working at 0.1 K, the energy resolution ideally can be as good as one eV for a practical detector. A detector with a resolution of 17 eV FWHM at 6 keV has been constructed. It is expected that this can be improved by a factor of two or more. With X-ray calorimeters flown on a sounding rocket, it should be possible to observe soft X-ray line emission from the interstellar medium over the energy range 0.07 to 1 keV. Here, a preliminary design for an X-ray calorimeter rocket experiment and the spectrum which might be observed from an equilibrium plasma are presented. For later X-ray calorimeter sounding rocket experiments, it is planned to add an aluminum foil mirror with collecting area of about 400 sq cm to observe line features from bright supernova remnants.

  7. Gain dynamics in a soft X-ray laser ampli er perturbed by a strong injected X-ray eld

    SciTech Connect

    Wang, Yong; Wang, Shoujun; Oliva, E; Lu, L; Berrill, Mark A; Yin, Liang; Nejdl, J; Luther, Brad; Proux, C; Le, T. T.; Dunn, James; Ros, D; Zeitoun, Philippe; Rocca, Jorge

    2014-01-01

    Seeding soft X-ray plasma ampli ers with high harmonics has been demonstrated to generate high-brightness soft X-ray laser pulses with full spatial and temporal coherence. The interaction between the injected coherent eld and the swept-gain medium has been modelled. However, no exper- iment has been conducted to probe the gain dynamics when perturbed by a strong external seed eld. Here, we report the rst X-ray pump X-ray probe measurement of the nonlinear response of a plasma ampli er perturbed by a strong soft X-ray ultra-short pulse. We injected a sequence of two time-delayed high-harmonic pulses (l518.9 nm) into a collisionally excited nickel-like molybdenum plasma to measure with femto-second resolution the gain depletion induced by the saturated ampli cation of the high-harmonic pump and its subsequent recovery. The measured fast gain recovery in 1.5 1.75 ps con rms the possibility to generate ultra-intense, fully phase-coherent soft X-ray lasers by chirped pulse ampli cation in plasma ampli ers.

  8. X-Ray Structure determination of the Glycine Cleavage System Protein H of Mycobacterium tuberculosis Using An Inverse Compton Synchrotron X-Ray Source

    PubMed Central

    Abendroth, Jan; McCormick, Michael S.; Edwards, Thomas E.; Staker, Bart; Loewen, Roderick; Gifford, Martin; Rifkin, Jeff; Mayer, Chad; Guo, Wenjin; Zhang, Yang; Myler, Peter; Kelley, Angela; Analau, Erwin; Hewitt, Stephen Nakazawa; Napuli, Alberto J.; Kuhn, Peter; Ruth, Ronald D.; Stewart, Lance J.

    2010-01-01

    Structural genomics discovery projects require ready access to both X-ray and NMR instrumentation which support the collection of experimental data needed to solve large numbers of novel protein structures. The most productive X-ray crystal structure determination laboratories make extensive frequent use of tunable synchrotron X-ray light to solve novel structures by anomalous diffraction methods. This requires that frozen cryo-protected crystals be shipped to large government-run synchrotron facilities for data collection. In an effort to eliminate the need to ship crystals for data collection, we have developed the first laboratory-scale synchrotron light source capable of performing many of the state-of-the-art synchrotron applications in X-ray science. This Compact Light Source is a first-in-class device that uses inverse Compton scattering to generate X-rays of sufficient flux, tunable wavelength and beam size to allow high-resolution X-ray diffraction data collection from protein crystals. We report on benchmarking tests of X-ray diffraction data collection with hen egg white lysozyme, and the successful high-resolution X-ray structure determination of the Glycine cleavage system protein H from Mycobacterium tuberculosis using diffraction data collected with the Compact Light Source X-ray beam. PMID:20364333

  9. Coherent X-ray diffraction from collagenous soft tissues

    PubMed Central

    Berenguer de la Cuesta, Felisa; Wenger, Marco P. E.; Bean, Richard J.; Bozec, Laurent; Horton, Michael A.; Robinson, Ian K.

    2009-01-01

    Coherent X-ray diffraction has been applied in the imaging of inorganic materials with great success. However, its application to biological specimens has been limited to some notable exceptions, due to the induced radiation damage and the extended nature of biological samples, the last limiting the application of most part of the phasing algorithms. X-ray ptychography, still under development, is a good candidate to overcome such difficulties and become a powerful imaging method for biology. We describe herein the feasibility of applying ptychography to the imaging of biological specimens, in particular collagen rich samples. We report here speckles in diffraction patterns from soft animal tissue, obtained with an optimized small angle X-ray setup that exploits the natural coherence of the beam. By phasing these patterns, dark field images of collagen within tendon, skin, bone, or cornea will eventually be obtained with a resolution of 60–70 nm. We present simulations of the contrast mechanism in collagen based on atomic force microscope images of the samples. Simulations confirmed the ‘speckled’ nature of the obtained diffraction patterns. Once inverted, the patterns will show the disposition and orientation of the fibers within the tissue, by enhancing the phase contrast between protein and no protein regions of the sample. Our work affords the application of the most innovative coherent X-ray diffraction tools to the study of biological specimens, and this approach will have a significant impact in biology and medicine because it overcomes many of the limits of current microscopy techniques. PMID:19706395

  10. Resonant magnetic scattering of polarized soft x rays

    SciTech Connect

    Sacchi, M.; Hague, C.F.; Gullikson, E.M.; Underwood, J.

    1997-04-01

    Magnetic effects on X-ray scattering (Bragg diffraction, specular reflectivity or diffuse scattering) are a well known phenomenon, and they also represent a powerful tool for investigating magnetic materials since it was shown that they are strongly enhanced when the photon energy is tuned across an absorption edge (resonant process). The resonant enhancement of the magnetic scattering has mainly been investigated at high photon energies, in order to match the Bragg law for the typical lattice spacings of crystals. In the soft X-ray range, even larger effects are expected, working for instance at the 2p edges of transition metals of the first row or at the 3d edges of rare earths (300-1500 eV), but the corresponding long wavelengths prevent the use of single crystals. Two approaches have been recently adopted in this energy range: (i) the study of the Bragg diffraction from artificial structures of appropriate 2d spacing; (ii) the analysis of the specular reflectivity, which contains analogous information but has no constraints related to the lattice spacing. Both approaches have their own specific advantages: for instance, working under Bragg conditions provides information about the (magnetic) periodicity in ordered structures, while resonant reflectivity can easily be related to electronic properties and absorption spectra. An important aspect common to all the resonant X-ray scattering techniques is the element selectivity inherent to the fact of working at a specific absorption edge: under these conditions, X-ray scattering becomes in fact a spectroscopy. Results are presented for films of iron and cobalt.

  11. Development of Computer Tomography System for the Soft X-ray Microscope at Ritsumeikan University

    SciTech Connect

    Ohigashi, T.; Fujii, H.; Usui, K.; Namba, H.; Mizutani, H.; Takemoto, K.; Kihara, H.

    2011-09-09

    A synchrotron-based full-field imaging soft x-ray microscope was tuned appropriately to perform computer tomography. The contrast and focal depth of the optical system were evaluated by using a Fresnel zone plate as a test object of variable spatial frequency. A focal depth of 15 {mu}m was obtained at the spatial frequency of 4.3 {mu}m{sup -1} according to Rayleigh's criterion. As a first trial of three-dimensional observation using this system, the cerebral cortex of the brain of a mouse, trimmed to a columnar shape by focused ion beam milling, was studied using a wavelength of 1.87-nm.

  12. Soft X-ray optics and technology; Proceedings of the Meeting, Berlin, Federal Republic of Germany, Dec. 8-11, 1986

    NASA Astrophysics Data System (ADS)

    Koch, Ernst-Eckhard; Schmahl, Guenter

    Recent advances in the design, construction, and application of soft X-ray (SX) sources and optics are discussed in reviews and reports. Topics addressed include VUV and SX sources, high-brightness synchrotron radiation sources, SX mirrors, instruments for X-ray astronomy satellites, and SX instrumentation for synchrotron sources. Consideration is given to VUV and SX optics, multilayers, SX scanning microscopy, microfabrication and zone plates, and SX radiometry and detectors. Diagrams, drawings, graphs, spectra, and sample images are provided.

  13. A soft x-ray transmission grating imaging-spectrometer for the National Ignition Facility

    SciTech Connect

    Moore, A S; Guymer, T M; Kline, J L; Morton, J; Taccetti, M; Lanier, N E; Bentley, C; Workman, J; Peterson, B; Mussack, K; Cowan, J; Prasad, R; Richardson, M; Burns, S; Kalantar, D H; Benedetti, L R; Bell, P; Bradley, D; Hsing, W; Stevenson, M

    2012-05-01

    A soft x-ray transmission grating spectrometer has been designed for use on high energy-density physics experiments at the National Ignition Facility (NIF); coupled to one of the NIF gated x-ray detectors (GXD) it records sixteen time-gated spectra between 250 and 1000eV with 100ps temporal resolution. The trade-off between spectral and spatial resolution leads to an optimized design for measurement of emission around the peak of a 100-300eV blackbody spectrum. Performance qualification results from the NIF, the Trident Laser Facility and VUV beamline at the National Synchrotron Light Source (NSLS), evidence a <100{micro}m spatial resolution in combination with a source-size limited spectral resolution that is <10eV at photon energies of 300eV.

  14. A soft x-ray transmission grating imaging-spectrometer for the National Ignition Facility

    NASA Astrophysics Data System (ADS)

    Moore, A. S.; Guymer, T. M.; Kline, J. L.; Morton, J.; Taccetti, M.; Lanier, N. E.; Bentley, C.; Workman, J.; Peterson, B.; Mussack, K.; Cowan, J.; Prasad, R.; Richardson, M.; Burns, S.; Kalantar, D. H.; Benedetti, L. R.; Bell, P.; Bradley, D.; Hsing, W.; Stevenson, M.

    2012-10-01

    A soft x-ray transmission grating spectrometer has been designed for use on high energy-density physics experiments at the National Ignition Facility (NIF); coupled to one of the NIF gated x-ray detectors it records 16 time-gated spectra between 250 and 1000 eV with 100 ps temporal resolution. The trade-off between spectral and spatial resolution leads to an optimized design for measurement of emission around the peak of a 100-300 eV blackbody spectrum. Performance qualification results from the NIF, the Trident Laser Facility and vacuum ultraviolet beamline at the National Synchrotron Light Source, evidence a <100 μm spatial resolution in combination with a source-size limited spectral resolution that is <10 eV at photon energies of 300 eV.

  15. Chemical Analysis of Impurity Boron Atoms in Diamond Using Soft X-ray Emission Spectroscopy

    SciTech Connect

    Muramatsu, Yasuji; Iihara, Junji; Takebe, Toshihiko; Denlinger, Jonathan D.

    2008-03-29

    To analyze the local structure and/or chemical states of boron atoms in boron-doped diamond, which can be synthesized by the microwave plasma-assisted chemical vapor deposition method (CVD-B-diamond) and the temperature gradient method at high pressure and high temperature (HPT-B-diamond), we measured the soft X-ray emission spectra in the CK and BK regions of B-diamonds using synchrotron radiation at the Advanced Light Source (ALS). X-ray spectral analyses using the fingerprint method and molecular orbital calculations confirm that boron atoms in CVD-B-diamond substitute for carbon atoms in the diamond lattice to form covalent B-C bonds, while boron atoms in HPT-B-diamond react with the impurity nitrogen atoms to form hexagonal boron nitride. This suggests that the high purity diamond without nitrogen impurities is necessary to synthesize p-type B-diamond semiconductors.

  16. Low energy soft x-ray emission spectrometer at BL-09A in NewSUBARU

    SciTech Connect

    Niibe, Masahito; Tokushima, Takashi

    2016-07-27

    A compact soft X-ray emission spectrometer for the energy region of 50-600 eV has been designed and constructed for the long undulator beamline BL-09A in the NewSUBARU synchrotron radiation (SR) facility. The optical design of the spectrometer is based on a grazing incidence flat-field spectrometer using a valid line-spacing grating. The average groove density of the grating is 2000 L/mm, and the angle of incidence to the grating is 86.5 deg. The distances from the slit to the grating and from the grating to the CCD are 355 mm and 650 mm, respectively. The energy resolution, E/ΔE, was estimated to be greater than 1000 in the energy range of 50-600 eV. Spectra of K-emission X-rays of several light elements, such as B, C, N, and O, from various samples were successfully obtained.

  17. Chemical analysis of impurity boron atoms in diamond using soft X-ray emission spectroscopy.

    PubMed

    Muramatsu, Yasuji; Iihara, Junji; Takebe, Toshihiko; Denlinger, Jonathan D

    2008-07-01

    To analyze the local structure and/or chemical states of boron atoms in boron-doped diamond, which can be synthesized by the microwave plasma-assisted chemical vapor deposition method (CVD-B-diamond) and the temperature gradient method at high pressure and high temperature (HPT-B-diamond), we measured the soft X-ray emission spectra in the CK and BK regions of B-diamonds using synchrotron radiation at the Advanced Light Source (ALS). X-ray spectral analyses using the fingerprint method and molecular orbital calculations confirm that boron atoms in CVD-B-diamond substitute for carbon atoms in the diamond lattice to form covalent B-C bonds, while boron atoms in HPT-B-diamond react with the impurity nitrogen atoms to form hexagonal boron nitride. This suggests that the high purity diamond without nitrogen impurities is necessary to synthesize p-type B-diamond semiconductors.

  18. Evaluation of surface figure error profile of ellipsoidal mirror for soft x-ray focusing

    NASA Astrophysics Data System (ADS)

    Takeo, Yoko; Saito, Takahiro; Mimura, Hidekazu

    2015-08-01

    It is possible to achieve soft X-ray nanofocusing with a high efficiency and no chromatic aberration by using an ultraprecise ellipsoidal mirror. Surface figure metrology is key in the improvement of surface figure accuracy. In this study, we propose a ptychographic phase retrieval method using a visible light laser to measure the surface figure error profile of an ellipsoidal mirror. We introduce a simple experimental system for ptychographic phase retrieval and demonstrate the basic performance of the proposed system. Obtainable wavefront information provides both the figure error and the alignment of the ellipsoidal mirror that yield the best focusing. This developed method is required for offline adjustments when an ellipsoidal mirror is installed in the beamline of synchrotron radiation or X-ray free-electron laser light sources.

  19. A soft x-ray transmission grating imaging-spectrometer for the National Ignition Facility

    SciTech Connect

    Moore, A. S.; Guymer, T. M.; Morton, J.; Bentley, C.; Stevenson, M.; Kline, J. L.; Taccetti, M.; Lanier, N. E.; Workman, J.; Peterson, B.; Mussack, K.; Cowan, J.; Prasad, R.; Richardson, M.; Burns, S.; Kalantar, D. H.; Benedetti, L. R.; Bell, P.; Bradley, D.; Hsing, W.

    2012-10-15

    A soft x-ray transmission grating spectrometer has been designed for use on high energy-density physics experiments at the National Ignition Facility (NIF); coupled to one of the NIF gated x-ray detectors it records 16 time-gated spectra between 250 and 1000 eV with 100 ps temporal resolution. The trade-off between spectral and spatial resolution leads to an optimized design for measurement of emission around the peak of a 100-300 eV blackbody spectrum. Performance qualification results from the NIF, the Trident Laser Facility and vacuum ultraviolet beamline at the National Synchrotron Light Source, evidence a <100 {mu}m spatial resolution in combination with a source-size limited spectral resolution that is <10 eV at photon energies of 300 eV.

  20. Neutron and Synchrotron X-Ray Scattering Studies of Superconductors

    SciTech Connect

    Tranquada,J.M.

    2008-09-01

    Superconductors hold the promise for a more stable and efficient electrical grid, but new isotropic, high-temperature superconductors are needed in order to reduce cable manufacturing costs. The effort to understand high-temperature superconductivity, especially in the layered cuprates, provides guidance to the search for new superconductors. Neutron scattering has long provided an important probe of the collective excitations that are involved in the pairing mechanism. For the cuprates, neutron and x-ray diffraction techniques also provide information on competing types of order, such as charge and spin stripes, that appear to be closely connected to the superconductivity. Recently, inelastic x-ray scattering has become competitive for studying phonons and may soon provide valuable information on electronic excitations. Examples of how these techniques contribute to our understanding of superconductivity are presented.

  1. (Synchrotron studies of x-ray reflectivity from surfaces)

    SciTech Connect

    Pershan, P.S.

    1992-03-03

    Following a long period of theoretical interest, but only limited measurements, there has recently been an increased number of attempts to expand the relative paucity of experimental information on the structure of liquid surfaces using techniques as diverse as ellipsometry, micro-force balances, non-linear optics, Auger and photoelectron spectroscopy, and x-ray scattering. Our group has played a leading role in the currently expanding application of scattering techniques to the general problem of characterizing the microscopic structure of liquid surfaces and we propose here that this work be extended specifically to liquid metals. In the following sections we will briefly describe the salient features of x-ray scattering that are relevant to the current project, the progress that we have made in the current grant period and the work that we propose to carry out in the forthcoming grant period.

  2. Synchrotron x-ray study of a Fibonacci superlattice

    SciTech Connect

    Todd, J.; Merlin, R.; Clarke, R.; Mohanty, K.M.; Axe, J.D.

    1986-09-01

    Quasiperiodic ordering is studied in a GaAs-AlAs Fibonacci superlattice by high-resolution x-ray scattering. The data are consistent with the predicted dense set of diffraction vectors. Moderately large growth fluctuations in the sequential deposition of GaAs and AlAs layers do not appear to disturb seriously the quasiperiodic order. The effects of randomness are analyzed in a computer simulation.

  3. X-ray Synchrotron Radiation in a Plasma Wiggler

    SciTech Connect

    Wang, Shuoquin; /UCLA /SLAC, SSRL

    2005-09-27

    A relativistic electron beam can radiate due to its betatron motion inside an ion channel. The ion channel is induced by the electron bunch as it propagates through an underdense plasma. In the theory section of this thesis the formation of the ion channel, the trajectories of beam electrons inside the ion channel, the radiation power and the radiation spectrum of the spontaneous emission are studied. The comparison between different plasma wiggler schemes is made. The difficulties in realizing stimulated emission as the beam traverses the ion channel are investigated, with particular emphasis on the bunching mechanism, which is important for the ion channel free electron laser. This thesis reports an experiment conducted at the Stanford Linear Accelerator Center (SLAC) to measure the betatron X-ray radiations for the first time. They first describe the construction and characterization of the lithium plasma source. In the experiment, the transverse oscillations of the SLAC 28.5 GeV electron beam traversing through a 1.4 meter long lithium plasma source are clearly seen. These oscillations lead to a quadratic density dependence of the spontaneously emitted betatron X-ray radiation. The divergence angle of the X-ray radiation is measured. The absolute photon yield and the spectral brightness at 14.2 KeV photon energy are estimated and seen to be in reasonable agreement with theory.

  4. Soft X-Ray Pulsations in Solar Flares

    NASA Astrophysics Data System (ADS)

    Simões, P. J. A.; Hudson, H. S.; Fletcher, L.

    2015-12-01

    The soft X-ray emissions ( hν>1.5 keV) of solar flares mainly come from the bright coronal loops at the highest temperatures normally achieved in the flare process. Their ubiquity has led to their use as a standard measure of flare occurrence and energy, although the overwhelming bulk of the total flare energy goes elsewhere. Recently Dolla et al. ( Astrophys. J. Lett. 749, L16, 2012) noted quasi-periodic pulsations (QPP) in the soft X-ray signature of the X-class flare SOL2011-02-15, as observed by the standard photometric data from the GOES ( Geostationary Operational Environmental Satellite) spacecraft. In this article we analyse the suitability of the GOES data for this type of analysis and find them to be generally valuable after September, 2010 (GOES-15). We then extend the result of Dolla et al. to a complete list of X-class flares from Cycle 24 and show that most of them (80 %) display QPPs in the impulsive phase. The pulsations show up cleanly in both channels of the GOES data, making use of time-series of irradiance differences (the digital time derivative on the 2-s sampling). We deploy different techniques to characterise the periodicity of GOES pulsations, considering the red-noise properties of the flare signals, finding a range of characteristic time scales of the QPPs for each event, but usually with no strong signature of a single period dominating in the power spectrum. The QPP may also appear on somewhat longer time scales during the later gradual phase, possibly with a greater tendency towards coherence, but the sampling noise in GOES difference data for high irradiance values (X-class flares) makes these more uncertain. We show that there is minimal phase difference between the differenced GOES energy channels, or between them and the hard X-ray variations on short time scales. During the impulsive phase, the footpoints of the newly forming flare loops may also contribute to the observed soft X-ray variations.

  5. Molecular orientation in soft matter thin films studied by resonant soft X-ray reflectivity

    SciTech Connect

    Mezger, Markus; Jerome, Blandine; Kortright, Jeffrey B.; Valvidares, Manuel; Gullikson, Eric; Giglia, Angelo; Mahne, Nicola; Nannarone, Stefano

    2011-01-12

    We present a technique to study depth profiles of molecular orientation in soft matter thin films with nanometer resolution. The method is based on dichroism in resonant soft X-ray reflectivity using linear s- and p-polarization. It combines the chemical sensitivity of Near-Edge X-ray Absorption Fine Structure spectroscopy to specific molecular bonds and their orientation relative to the polarization of the incident beam with the precise depth profiling capability of X-ray reflectivity. We demonstrate these capabilities on side chain liquid crystalline polymer thin films with soft X-ray reflectivity data at the carbon K edge. Optical constants of the anisotropic refractive index ellipsoid were obtained from a quantitative analysis using the Berreman formalism. For films up to 50 nm thickness we find that the degree of orientation of the long axis exhibits no depth variation and isindependent of the film thickness.

  6. The Onset Phase of "Soft" X-Ray Transients

    NASA Astrophysics Data System (ADS)

    Hebb Swank, Jean; Shaposhnikov, N.; Shrader, C. R.; Rupen, M. P.; Beckmann, V.; Markwardt, C. B.; Smith, D. A.

    2006-09-01

    Transient outbursts of black holes and neutron stars in X-ray binaries with low-mass companions start with a flickering hard power-law flux that contains a low frequency quasi-periodic oscillation (QPO). The frequency of the QPO may reflect the outer boundary of the coronal emission and its inward motion toward the compact object. It has also been proposed that the hard flux is related to the base of a radio emitting outflow or compact jet. We had detailed observations of the beginning of the 2005 outburst of GRO J1655-40 with RXTE, INTEGRAL, the VLA and ROTSE. We use the X-ray, radio, and optical results in the context of these models to address their applicability to the onset of the outburst and to specify the physical parameters. Decline of the radio flux as both the power-law and disk flux increased constrains the amount of synchrotron self-Compton emission. Values are compared to those of other black hole and neutron star transients. We are glad to acknowledge support by a NASA INTEGRAL Guest Observer Grant and by the RXTE project, NRAO, and ROTSE.

  7. Thin conductive diamond films as beam intensity monitors for soft x-ray beamlines

    SciTech Connect

    Kummer, K.; Fondacaro, A.; Yakhou-Harris, F.; Sessi, V.; Brookes, N. B.; Pobedinskas, P.; Janssens, S. D.; Haenen, K.; Williams, O. A.; Hees, J.

    2013-03-15

    Quantitative analysis of X-ray absorption and dichroism data requires knowledge of the beamline photon flux during the measurements. We show that thin conductive (B-doped) diamond thin films can be an alternative to the widely used gold meshes for monitoring the beam intensity of soft X-ray beamlines in situ. Limited by the carbon extended x-ray absorption fine structure oscillations, the diamond films become applicable beginning from about 600 eV photon energy, where the important transition metal edges and the rare-earth edges are found. The 100 nm and 250 nm thick free-standing diamond films were grown and tested against standard gold meshes in real-life dichroism experiments performed at beamline ID08 of the European Synchrotron Radiation Facility, Grenoble, France. Quantitative agreement was found between the two experimental data sets. The films feature an extremely high transmission of about 90% and, at the same time, yield a sufficiently strong and clean reference signal. Furthermore, the thin films do not affect the shape of the transmitted beam. X-rays passing mesh-type monitors are subject to diffraction effects, which widen the beam and become particularly disturbing for small beamsizes in the micrometer range.

  8. Thin conductive diamond films as beam intensity monitors for soft x-ray beamlines

    NASA Astrophysics Data System (ADS)

    Kummer, K.; Fondacaro, A.; Yakhou-Harris, F.; Sessi, V.; Pobedinskas, P.; Janssens, S. D.; Haenen, K.; Williams, O. A.; Hees, J.; Brookes, N. B.

    2013-03-01

    Quantitative analysis of X-ray absorption and dichroism data requires knowledge of the beamline photon flux during the measurements. We show that thin conductive (B-doped) diamond thin films can be an alternative to the widely used gold meshes for monitoring the beam intensity of soft X-ray beamlines in situ. Limited by the carbon extended x-ray absorption fine structure oscillations, the diamond films become applicable beginning from about 600 eV photon energy, where the important transition metal edges and the rare-earth edges are found. The 100 nm and 250 nm thick free-standing diamond films were grown and tested against standard gold meshes in real-life dichroism experiments performed at beamline ID08 of the European Synchrotron Radiation Facility, Grenoble, France. Quantitative agreement was found between the two experimental data sets. The films feature an extremely high transmission of about 90% and, at the same time, yield a sufficiently strong and clean reference signal. Furthermore, the thin films do not affect the shape of the transmitted beam. X-rays passing mesh-type monitors are subject to diffraction effects, which widen the beam and become particularly disturbing for small beamsizes in the micrometer range.

  9. Single-stepper soft x-ray source for step-and-scan tools

    NASA Astrophysics Data System (ADS)

    Piestrup, Melvin A.; Powell, Michael W.; Mrowka, Stanley; Lombardo, Louis W.; Chase, Michael B.; Cremer, J. Theodore; Maruyama, Xavier K.

    1997-07-01

    As a synchrotron equivalent, this paper presents a single- stepper, soft-x-ray source which offers high brightness, high collimation (less than 20 mr global and less than 2 mr local), modest operating vacuum, excellent spectrum and moderate cost. The x-rays are generated by a process called transition radiation (TR). Electrons of moderate energy (e.g. 17 - 100 MeV) pass through thin-metal foils producing a forward- directed cone of x-rays whose photon energies can be between 0.5 and 3 keV. The optimum radiator consists of many thin- metal foils, e.g. beryllium, which are separated by vacuum. The x-ray wavelength an be optimized for highest photoresist sensitivity, e.g. 1.4 nm. A computer simulation shows that for beam-shaping (slit formation) and collimation, a single grazing-angle optic transforms the radiator cone into a slit (5 mm by 26 mm) in the 1X wafer image plane, having an energy density of 15 - 60 mJ/cm2. This slit is then scanned for dose uniformity. In a proof-of-principle experiment, an apparatus utilizing a Au-coated grazing-angle optic was used to focus transition radiation to a slit (7 mm by 16 mm) in the image plane at 631 mm from the optic and 881 mm from the TR radiator. Intensity variation across the longitudinal direction (approximately 10 mm) of the slit was less than 5%.

  10. The Soft X-ray Spectrophotometer SphinX for the CORONAS-Photon Mission

    NASA Astrophysics Data System (ADS)

    Sylwester, Janusz; Kowalinski, Miroslaw; Szymon, Gburek; Bakala, Jaroslaw; Kuzin, Sergey; Kotov, Yury; Farnik, Frantisek; Reale, Fabio

    The purpose, construction details and calibration results of the new design, Polish-led solar X-ray spectrophotometer SphinX will be presented. The instrument constitutes a part of the Russian TESIS X-ray and EUV complex aboard the forthcoming CORONAS-Photon solar mission to be launched later in 2008. SphinX uses Si-PIN detectors for high time resolution (down to 0.01 s) measurements of solar spectra in the energy range between 0.5 keV and 15 keV. The spectral resolution allows separating 256 individual energy channels in this range with particular groups of lines clearly distinguishable. Unprecedented accuracy of the instrument calibration at the XACT (Palermo) and BESSY (Berlin) synchrotron will allow for establishing the solar soft X-ray photometric reference system. The cross-comparison between SphinX and the other instruments presently in orbit like XRT on Hinode, RHESSI and GOES X-ray monitor, will allow for a precise determination of the coronal emission measure and temperature during both very low and very high activity periods. Examples of the detectors' ground calibration results as well as the calculated synthetic spectra will be presented. The operation of the instrument while in orbit will be discussed allowing for suggestions from other groups to be still included in mission planning.

  11. Imaging bacterial spores by soft-x-ray microscopy

    SciTech Connect

    Stead, A.D.; Ford, T.W.; Judge, J.

    1997-04-01

    Bacterial spores are able to survive dehydration, but neither the physiological nor structural basis of this have been fully elucidated. Furthermore, once hydrated, spores often require activation before they will germinate. Several treatments can be used to activate spores, but in the case of Bacillus subtlis the most effective is heat treatment. The physiological mechanism associated with activation is also not understood, but some workers suggest that the loss of calcium from the spores may be critical. However, just prior to germination, the spores change from being phase bright to phase dark when viewed by light microscopy. Imaging spores by soft x-ray microscopy is possible without fixation. Thus, in contrast to electron microscopy, it is possible to compare the structure of dehydrated and hydrated spores in a manner not possible previously. A further advantage is that it is possible to monitor individual spores by phase contrast light microscopy immediately prior to imaging with soft x-rays; whereas, with both electron microscopy and biochemical studies, it is a population of spores being studied without knowledge of the phase characteristics of individual spores. This study has therefore tried to compare dehydrated and hydrated spores and to determine if there is a mass loss from individual spores as they pass the transition from being phase bright to phase dark.

  12. Note: Dynamic strain field mapping with synchrotron X-ray digital image correlation

    SciTech Connect

    Lu, L.; Fan, D.; Luo, S. N.; Bie, B. X.; Ran, X. X.; Qi, M. L.; Parab, N.; Sun, J. Z.; Liao, H. J.; Hudspeth, M. C.; Claus, B.; Fezzaa, K.; Sun, T.; Chen, W.; Gong, X. L.

    2014-07-15

    We present a dynamic strain field mapping method based on synchrotron X-ray digital image correlation (XDIC). Synchrotron X-ray sources are advantageous for imaging with exceptional spatial and temporal resolutions, and X-ray speckles can be produced either from surface roughness or internal inhomogeneities. Combining speckled X-ray imaging with DIC allows one to map strain fields with high resolutions. Based on experiments on void growth in Al and deformation of a granular material during Kolsky bar/gas gun loading at the Advanced Photon Source beamline 32ID, we demonstrate the feasibility of dynamic XDIC. XDIC is particularly useful for dynamic, in-volume, measurements on opaque materials under high strain-rate, large, deformation.

  13. Synthesis of metallic nanoparticles through X-ray radiolysis using synchrotron radiation

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Akinobu; Okada, Ikuo; Fukuoka, Takao; Sakurai, Ikuya; Utsumi, Yuichi

    2016-05-01

    The potential to fabricate metallic nanoparticles directly on silicon substrates from liquid solutions is ideal for three-dimensional lithography systems, drug delivery materials, and sensing applications. Here, we report the successful synthesis of Au, Cu, and Fe nanoparticles from the corresponding liquid solutions [gold(I) trisodium disulphite, copper(II) sulfate, and potassium ferricyanide] by synchrotron (SR) X-ray irradiation. The deposition of gold nanoparticles in the gold(I) trisodium disulphite solution was performed by monochromatic X-ray exposure from synchrotron radiation. The use of ethanol as an additive enabled the nucleation and growth of Cu particles, while no Cu particles were produced in the copper sulfate solution without ethanol with polychromatic SR X-ray irradiation. Fe particles were generated by direct polychromatic SR X-ray irradiation. These results demonstrate the behavior of three-dimensional printers, enabling us to build composite material structures with metallic and plastic materials.

  14. Synchronizing fast electrically driven phenomena with synchrotron x-ray probes

    SciTech Connect

    Grigoriev, Alexei; Do, D.-H.; Evans, Paul G.; Adams, Bernhard; Landahl, Eric; Dufresne, Eric M.

    2007-02-15

    Time scales of long-range physical processes in solids are typically in the range of picoseconds to nanoseconds. These times are commensurate with the time resolution of structural probes based on modern synchrotron x-ray sources. Several processes of technological and scientific interest can be driven by applied electric fields, but synchronizing electrically driven phenomena with an x-ray probe poses a technical challenge. We describe the synchronization of a well-defined number of fast electrical pulses with the time structure of synchrotron x rays to probe the dynamics of thin films and nanostructures. This synchronization technique yields x-ray transient signals with 600 ps transitions in ferroelectric thin films, with a contribution of approximately 320 ps due to timing jitter in the synchronization.

  15. X-ray analog pixel array detector for single synchrotron bunch time-resolved imaging.

    PubMed

    Koerner, Lucas J; Gruner, Sol M

    2011-03-01

    Dynamic X-ray studies can reach temporal resolutions limited by only the X-ray pulse duration if the detector is fast enough to segregate synchrotron pulses. An analog integrating pixel array detector with in-pixel storage and temporal resolution of around 150 ns, sufficient to isolate pulses, is presented. Analog integration minimizes count-rate limitations and in-pixel storage captures successive pulses. Fundamental tests of noise and linearity as well as high-speed laser measurements are shown. The detector resolved individual bunch trains at the Cornell High Energy Synchrotron Source at levels of up to 3.7 × 10(3) X-rays per pixel per train. When applied to turn-by-turn X-ray beam characterization, single-shot intensity measurements were made with a repeatability of 0.4% and horizontal oscillations of the positron cloud were detected.

  16. X-ray analog pixel array detector for single synchrotron bunch time-resolved imaging

    PubMed Central

    Koerner, Lucas J.; Gruner, Sol M.

    2011-01-01

    Dynamic X-ray studies can reach temporal resolutions limited by only the X-ray pulse duration if the detector is fast enough to segregate synchrotron pulses. An analog integrating pixel array detector with in-pixel storage and temporal resolution of around 150 ns, sufficient to isolate pulses, is presented. Analog integration minimizes count-rate limitations and in-pixel storage captures successive pulses. Fundamental tests of noise and linearity as well as high-speed laser measurements are shown. The detector resolved individual bunch trains at the Cornell High Energy Synchrotron Source at levels of up to 3.7 × 103 X-rays per pixel per train. When applied to turn-by-turn X-ray beam characterization, single-shot intensity measurements were made with a repeatability of 0.4% and horizontal oscillations of the positron cloud were detected. PMID:21335901

  17. DEVELOPMENTS IN SYNCHROTRON X-RAY COMPUTED MICROTOMOGRAPHY AT THE NATIONAL SYNCHROTRON LIGHT SOURCE.

    SciTech Connect

    DOWD,B.A.

    1999-07-23

    Last year, the X27A beamline at the National Synchrotron Light Source (NSLS) became dedicated solely to X-Ray Computed Microtomography (XCMT). This is a third-generation instrument capable of producing tomographic volumes of 1-2 micron resolution over a 2-3mm field of view. Recent enhancements will be discussed. These have focused on two issues: the desire for real-time data acquisition and processing and the need for highly monochromatic beam (.1 % energy bandpass). The latter will permit k-edge subtraction studies and will provide improved image contrast from below the Cr (6 keV) up to the Cs (36 keV) k-edge. A range of applications that benefit from these improvements will be discussed as well. These two goals are somewhat counterproductive, however; higher monochromaticity yields a lower flux forcing longer data acquisition times. To balance the two, a more efficient scintillator for X-ray conversion is being developed. Some testing of a prototype scintillator has been performed; preliminary results will be presented here. In the meantime, data reconstruction times have been reduced, and the entire tomographic acquisition, reconstruction and volume rendering process streamlined to make efficient use of synchrotron beam time. A Fast Filtered Back Transform (FFBT) reconstruction program recently developed helped to reduce the time to reconstruct a volume of 150 x 150 x 250 pixels{sup 3} (over 5 million voxels) from the raw camera data to 1.5 minutes on a dual R10,000 CPU. With these improvements, one can now obtain a ''quick look'' of a small tomographic volume ({approximately}10{sup 6}voxels) in just over 15 minutes from the start of data acquisition.

  18. Model experiment of in vivo synchrotron X-ray diffraction of human kidney stones

    NASA Astrophysics Data System (ADS)

    Ancharov, A. I.; Potapov, S. S.; Moiseenko, T. N.; Feofilov, I. V.; Nizovskii, A. I.

    2007-05-01

    The diffraction of synchrotron radiation (SR) was used to explore the phase composition of kidney stones placed into a specific object phantom, which imitated the human body. As an imitation of the patient breath, the kidney stone was moved vertically and rotated to an angle of 15° during the recording of the X-ray pattern. It was shown that rotation and displacement did not distort the X-ray pattern.

  19. X-Ray-induced Deuterium Enrichment of N-rich Organics in Protoplanetary Disks: An Experimental Investigation Using Synchrotron Light

    NASA Astrophysics Data System (ADS)

    Gavilan, Lisseth; Remusat, Laurent; Roskosz, Mathieu; Popescu, Horia; Jaouen, Nicolas; Sandt, Christophe; Jäger, Cornelia; Henning, Thomas; Simionovici, Alexandre; Lemaire, Jean Louis; Mangin, Denis; Carrasco, Nathalie

    2017-05-01

    The deuterium enrichment of organics in the interstellar medium, protoplanetary disks, and meteorites has been proposed to be the result of ionizing radiation. The goal of this study is to simulate and quantify the effects of soft X-rays (0.1-2 keV), an important component of stellar radiation fields illuminating protoplanetary disks, on the refractory organics present in the disks. We prepared tholins, nitrogen-rich organic analogs to solids found in several astrophysical environments, e.g., Titan’s atmosphere, cometary surfaces, and protoplanetary disks, via plasma deposition. Controlled irradiation experiments with soft X-rays at 0.5 and 1.3 keV were performed at the SEXTANTS beamline of the SOLEIL synchrotron, and were immediately followed by ex-situ infrared, Raman, and isotopic diagnostics. Infrared spectroscopy revealed the preferential loss of singly bonded groups (N-H, C-H, and R-N≡C) and the formation of sp3 carbon defects with signatures at ˜1250-1300 cm-1. Raman analysis revealed that, while the length of polyaromatic units is only slightly modified, the introduction of defects leads to structural amorphization. Finally, tholins were measured via secondary ion mass spectrometry to quantify the D, H, and C elemental abundances in the irradiated versus non-irradiated areas. Isotopic analysis revealed that significant D-enrichment is induced by X-ray irradiation. Our results are compared to previous experimental studies involving the thermal degradation and electron irradiation of organics. The penetration depth of soft X-rays in μm-sized tholins leads to volume rather than surface modifications: lower-energy X-rays (0.5 keV) induce a larger D-enrichment than 1.3 keV X-rays, reaching a plateau for doses larger than 5 × 1027 eV cm-3. Synchrotron fluences fall within the expected soft X-ray fluences in protoplanetary disks, and thus provide evidence of a new non-thermal pathway to deuterium fractionation of organic matter.

  20. Report of the second workshop on synchrotron radiation sources for x-ray lithography

    SciTech Connect

    Barton, M.Q.; Craft, B.; Williams, G.P.

    1986-01-01

    The reported workshop is part of an effort to implement a US-based x-ray lithography program. Presentations include designs for three storage rings (one superconducting and two conventional) and an overview of a complete lithography program. The background of the effort described, the need for synchrotron radiation, and the international competition in the area are discussed briefly. The technical feasibility of x-ray lithography is discussed, and synchrotron performance specifications and construction options are given, as well as a near-term plan. It is recommended that a prototype synchrotron source be built as soon as possible, and that a research and development plan on critical technologies which could improve cost effectiveness of the synchrotron source be established. It is further recommended that a small number of second generation prototype synchrotrons be distributed to IC manufacturing centers to expedite commercialization. (LEW)

  1. Roles of oxidative stress in synchrotron radiation X-ray-induced testicular damage of rodents

    PubMed Central

    Ma, Yingxin; Nie, Hui; Sheng, Caibin; Chen, Heyu; Wang, Ban; Liu, Tengyuan; Shao, Jiaxiang; He, Xin; Zhang, Tingting; Zheng, Chaobo; Xia, Weiliang; Ying, Weihai

    2012-01-01

    Synchrotron radiation (SR) X-ray has characteristic properties such as coherence and high photon flux, which has excellent potential for its applications in medical imaging and cancer treatment. However, there is little information regarding the mechanisms underlying the damaging effects of SR X-ray on biological tissues. Oxidative stress plays an important role in the tissue damage induced by conventional X-ray, while the role of oxidative stress in the tissue injury induced by SR X-ray remains unknown. In this study we used the male gonads of rats as a model to study the roles of oxidative stress in SR X-ray-induced tissue damage. Exposures of the testes to SR X-ray at various radiation doses did not significantly increase the lipid peroxidation of the tissues, assessed at one day after the irradiation. No significant decreases in the levels of GSH or total antioxidation capacity were found in the SR X-ray-irradiated testes. However, the SR X-ray at 40 Gy induced a marked increase in phosphorylated H2AX – a marker of double-strand DNA damage, which was significantly decreased by the antioxidant N-acetyl cysteine (NAC). NAC also attenuated the SR X-ray-induced decreases in the cell layer number of seminiferous tubules. Collectively, our observations have provided the first characterization of SR X-ray-induced oxidative damage of biological tissues: SR X-ray at high doses can induce DNA damage and certain tissue damage during the acute phase of the irradiation, at least partially by generating oxidative stress. However, SR X-ray of various radiation doses did not increase lipid peroxidation. PMID:22837810

  2. Gas scintillation proportional counters for x-ray synchrotron applications

    SciTech Connect

    Smith, A. ); Bavdaz, M. )

    1992-01-01

    Gas scintillation proportional counters (GSPCs) as x-ray detectors provide some advantages and disadvantages compared with proportional counters. In this paper the various configurations of xenon filled GSPC are described including both imaging and nonimaging devices. It is intended that this work be used to configure a GSPC for a particular application and predict its general performance characteristics. The general principles of operation are described and the performance characteristics are then separately considered. A high performance, imaging, driftless GSPC is described in which a single intermediate window is used between the PMT and gas cell.

  3. Developments in gas detectors for synchrotron x-ray radiation

    SciTech Connect

    Fischer, J.; Radeka, V.; Smith, G.C.

    1985-09-01

    New results on the physical limitations to position resolution in gas detectors for x-rays (approx. =3 to 20 keV) due to the range of photoelectrons and Auger electrons are discussed. These results were obtained with a small gap detector in which position readout was accomplished by using a very low noise centroid finding technique. A description is given of position sensitive detectors for medium rates (a few x 10/sup 5/ photons per second), using delay line readout, and for very high rates (approx. =10/sup 8/ photons per second), using fast signal shaping on the output of each anode wire.

  4. X-ray/UV variability and the origin of soft X-ray excess emission from II Zw 177

    NASA Astrophysics Data System (ADS)

    Pal, Main

    We study a detailed broad-band X-ray/UV emission from the narrow line Seyfert 1 galaxy II Zw 177 based on two XMM-Newton and single Swift/XRT observations. Both XMM-Newton observations show the soft X-ray excess emission below 2 keV when the best-fit 2 - 10 keV power law is extrapolated down to 0.3 keV. We find the blurred reflection from an ionized accretion disc and Comptonized disc emission both describe the observed soft excess well. We find a remarkable trend of decreasing UV flux with increasing soft X-ray excess and power law emission. We suggest that this could be due to that the external edge of corona hide a fraction of accretion disk. Co-Author: Prof. Gulab C. Dewangan (IUCAA), Prof. Ranjeev Misra (IUCAA), Pramod Kumar (Nanded university)

  5. Synchrotron X-ray PIV Technique for Measurement of Blood Flow Velocity

    SciTech Connect

    Kim, Guk Bae; Lee, Sang Joon; Je, Jung Ho

    2007-01-19

    Synchrotron X-ray micro-imaging method has been used to observe internal structures of various organisms, industrial devices, and so on. However, it is not suitable to see internal flows inside a structure because tracers typically employed in conventional optical flow visualization methods cannot be detectable with the X-ray micro-imaging method. On the other hand, a PIV (particle image velocimetry) method which has recently been accepted as a reliable quantitative flow visualization technique can extract lots of flow information by applying digital image processing techniques However, it is not applicable to opaque fluids such as blood. In this study, we combined the PIV method and the synchrotron X-ray micro-imaging technique to compose a new X-ray PIV technique. Using the X-ray PIV technique, we investigated the optical characteristics of blood for a coherent synchrotron X-ray beam and quantitatively visualized real blood flows inside an opaque tube without any contrast media. The velocity field information acquired would be helpful for investigating hemorheologic characteristics of the blood flow.

  6. High Resolution X-Ray Diffraction of Macromolecules with Synchrotron Radiation

    NASA Technical Reports Server (NTRS)

    Stojanoff, Vivian; Boggon, Titus; Helliwell, John R.; Judge, Russell; Olczak, Alex; Snell, Edward H.; Siddons, D. Peter; Rose, M. Franklin (Technical Monitor)

    2000-01-01

    We recently combined synchrotron-based monochromatic X-ray diffraction topography methods with triple axis diffractometry and rocking curve measurements: high resolution X-ray diffraction imaging techniques, to better understand the quality of protein crystals. We discuss these methods in the light of results obtained on crystals grown under different conditions. These non destructive techniques are powerful tools in the characterization of the protein crystals and ultimately will allow to improve, develop, and understand protein crystal growth. High resolution X-ray diffraction imaging methods will be discussed in detail in light of recent results obtained on Hen Egg White Lysozyme crystals and other proteins.

  7. Requirements for X-ray structure analysis with modern synchrotron light sources

    NASA Astrophysics Data System (ADS)

    Laggner, Peter

    2000-11-01

    X-ray diffraction methods, including macromolecular crystallography, small-angle scattering from partly or noncrystalline systems, fiber and surface diffraction, are in the forefront of interest of a broad synchrotron user community from biomedical and technological fields. The main impact comes from the unsurpassed X-ray flux and brilliance of modern third-generation sources, facilitating on the one hand, a dramatic enhancement in sample throughput, and on the other hand, the transformation of X-ray diffraction analysis from a static to a cinematographic technique. In the present article some of the requirements for further development are being discussed.

  8. High Resolution X-Ray Diffraction of Macromolecules with Synchrotron Radiation

    NASA Technical Reports Server (NTRS)

    Stojanoff, Vivian; Boggon, Titus; Helliwell, John R.; Judge, Russell; Olczak, Alex; Snell, Edward H.; Siddons, D. Peter; Rose, M. Franklin (Technical Monitor)

    2000-01-01

    We recently combined synchrotron-based monochromatic X-ray diffraction topography methods with triple axis diffractometry and rocking curve measurements: high resolution X-ray diffraction imaging techniques, to better understand the quality of protein crystals. We discuss these methods in the light of results obtained on crystals grown under different conditions. These non destructive techniques are powerful tools in the characterization of the protein crystals and ultimately will allow to improve, develop, and understand protein crystal growth. High resolution X-ray diffraction imaging methods will be discussed in detail in light of recent results obtained on Hen Egg White Lysozyme crystals and other proteins.

  9. Chemical mapping of paleontological and archeological artifacts with synchrotron X-rays.

    PubMed

    Bergmann, Uwe; Manning, Phillip L; Wogelius, Roy A

    2012-01-01

    The application of the recently developed synchrotron rapid scanning X-ray fluorescence (SRS-XRF) technique to the mapping of large objects is the focus of this review. We discuss the advantages of SRS-XRF over traditional systems and the use of other synchrotron radiation (SR) techniques to provide corroborating spectroscopic and diffraction analyses during the same analytical session. After reviewing routine techniques used to analyze precious specimens, we present several case studies that show how SR-based methods have been successfully applied in archeology and paleontology. For example, SRS-XRF imaging of a seventh-century Qur'ān palimpsest and an overpainted original opera score from Luigi Cherubini is described. We also review the recent discovery of soft-tissue residue in fossils of Archaeopteryx and an ancient reptile, as well as work that has successfully resolved the remnants of pigment in Confuciusornis sanctus, a 120-million-year-old fossil of the oldest documented bird with a fully derived avian beak.

  10. X-ray emission from cataclysmic variables with accretion disks. I - Hard X-rays. II - EUV/soft X-ray radiation

    NASA Technical Reports Server (NTRS)

    Patterson, J.; Raymond, J. C.

    1985-01-01

    Theoretical models explaining the hard-X-ray, soft-X-ray, and EUV emission of accretion-disk cataclysmic variables in terms of the disk boundary layer (DBL) are developed on the basis of a survey of the published observational data. The data are compared with model predictions in graphs for systems with high or low (greater than or less than 10-Pg/s) accretion rates. Good agreement is obtained both at low accretion rates, where an optically thin rarefied hot (Te = 10 to the 8th K) DBL radiates most of its energy as hard X-rays, and at high accretion rates, where an optically thick 100,000-K DBL radiates most of its energy in the EUV and as soft X-rays. Detailed analysis of the old nova V603 Aql suggests that previous models predicting more detections of soft-X-ray/EUV emissions from thick-DBL objects (Ferland et al., 1982) used inappropriate dwarf masses, interstellar column densities, or classical-nova space densities.

  11. X-ray emission from cataclysmic variables with accretion disks. I - Hard X-rays. II - EUV/soft X-ray radiation

    NASA Technical Reports Server (NTRS)

    Patterson, J.; Raymond, J. C.

    1985-01-01

    Theoretical models explaining the hard-X-ray, soft-X-ray, and EUV emission of accretion-disk cataclysmic variables in terms of the disk boundary layer (DBL) are developed on the basis of a survey of the published observational data. The data are compared with model predictions in graphs for systems with high or low (greater than or less than 10-Pg/s) accretion rates. Good agreement is obtained both at low accretion rates, where an optically thin rarefied hot (Te = 10 to the 8th K) DBL radiates most of its energy as hard X-rays, and at high accretion rates, where an optically thick 100,000-K DBL radiates most of its energy in the EUV and as soft X-rays. Detailed analysis of the old nova V603 Aql suggests that previous models predicting more detections of soft-X-ray/EUV emissions from thick-DBL objects (Ferland et al., 1982) used inappropriate dwarf masses, interstellar column densities, or classical-nova space densities.

  12. X-ray holographic microscopy experiments at the Brookhaven synchrotron light source

    SciTech Connect

    Howells, M.R.; Iarocci, M.; Kenney, J.; Kirz, J.; Rarback, H.

    1983-01-01

    Soft x-ray holographic microscopy is discussed from an experimental point of view. Three series of measurements have been carried out using the Brookhaven 750 MeV storage ring as an x-ray source. Young slits fringes, Gabor (in line) holograms and various data pertaining to the soft x-ray performance of photographic plates are reported. The measurements are discussed in terms of the technique for recording them and the experimental limitations in effect. Some discussion is also given of the issues involved in reconstruction using visible light.

  13. Evaluation of different synchrotron beamline configurations for X-ray fluorescence analysis of environmental samples.

    PubMed

    Barberie, Sean R; Iceman, Christopher R; Cahill, Catherine F; Cahill, Thomas M

    2014-08-19

    Synchrotron radiation X-ray fluorescence (SR-XRF) is a powerful elemental analysis tool, yet synchrotrons are large, multiuser facilities that are generally not amenable to modification. However, the X-ray beamlines from synchrotrons can be modified by simply including X-ray filters or removing monochromators to improve the SR-XRF analysis. In this study, we evaluated four easily applied beamline configurations for the analysis of three representative environmental samples, namely a thin aerosol sample, an intermediate thickness biological sample, and a thick rare earth mineral specimen. The results showed that the "white beam" configuration, which was simply the full, polychromatic output of the synchrotron, was the optimal configuration for the analysis of thin samples with little mass. The "filtered white beam" configuration removed the lower energy X-rays from the excitation beam so it gave better sensitivity for elements emitting more energetic X-rays. The "filtered white beam-filtered detector" configuration sacrifices the lower energy part of the spectrum (<15 keV) for improved sensitivity in the higher end (∼26 to 48 keV range). The use of a monochromatic beam, which tends to be the standard mode of operation for most SR-XRF analyses reported in the literature, gave the least sensitive analysis.

  14. Introducing a New Capability at SSRL: Resonant Soft X-ray Scattering

    NASA Astrophysics Data System (ADS)

    Lee, Jun-Sik; Jang, Hoyoung; Lu, Donghui; Kao, Chi-Chang

    Stanford Synchrotron Radiation Lightsource (SSRL) at SLAC recently developed a setup for the resonant soft x-ray scattering (RSXS). In general, the RSXS technique uniquely probes not only structural information, but also chemical specific information. This is because this technique can explore the spatial periodicities of charge, orbital, spin, and lattice with spectroscopic aspect. Moreover, the soft x-ray range is particularly relevant for a study of soft materials as it covers the K-edge of C, N, F, and O, as well as the L-edges of transition metals and M-edges of rare-earth elements. Hence, the RSXS capability has been regarded as a very powerful technique for investigating the intrinsic properties of materials such as quantum- and energy-materials. The RSXS capability at the SSRL composes of in-vacuum 4-circle diffractometer. There are also the fully motorized sample-motion manipulations. Also, the sample can be cooled down to 25 K via the liquid helium. This capability has been installed at BL 13-3, where the photon source is from elliptically polarized undulator (EPU). Covering the photon energies is from 230 eV to 1400 eV. Furthermore, this EPU system offers more degree of freedoms for controlling x-ray polarizations (linear and circular). Using the advance of controlling x-ray polarization, we can also investigate a morphology effect of local domain/grain in materials. The detailed introduction of the RSXS end-station and several results will be touched in this poster presentation.

  15. SAS 3 survey of the soft X-ray background

    NASA Technical Reports Server (NTRS)

    Marshall, F. J.; Clark, G. W.

    1984-01-01

    The results of a survey of the soft X-ray sky in the C band (0.10-0.28keV) are reported. The observations were carried out using two independent flow proportional counters on board the SAS 3 X-ray satellite which had a total angular resolution of 2.9 deg FWHM, and a total exposure of 2.2 x 10 to the 4th per sq cm s sr. It is found that C band counting rates were generally inversely correlated with the column density of the neutral hydrogen on all angular scales down to the lowest angular resolution of the detectors. In the region 90-180 deg l and 0-10 deg b, the relation between C-band rates and the column densities of neutral hydrogen was fitted with a residual rms deviation of less than 13 percent by a two-component numerical model of the X-ray background. For the apparent attenuation column density a value of 2.7 x 10 to the 20th per sq cm was obtained. On the basis of a computer simulation of the SAS 3 data, it is shown that the observed clumping of interstellar matter was consistent with the magnitude of spatial fluctuations in the C-band map. When the background rates were subtracted from the survey map, the subsequent map showed foreground emission and absorption features with improved sensitivity and clarity. A series of computer-generated maps incorporating the SAS 3 data is given in an appendix.

  16. Detection of soft X-rays from Alpha Lyrae and Eta Bootis with an imaging X-ray telescope

    NASA Technical Reports Server (NTRS)

    Topka, K.; Fabricant, D.; Harnden, F. R., Jr.; Gorenstein, P.; Rosner, R.

    1979-01-01

    Results are presented for observations of Alpha Lyr (Vega) and Eta Boo with an imaging X-ray telescope during two rocket flights. It is found that Vega and Eta Boo are soft X-ray sources with respective luminosities of approximately 3 x 10 to the 28th erg/s (0.15-0.8 keV) and 1 x 10 to the 29th erg/s (0.15-1.5 keV). Surface X-ray luminosities of about 640,000 erg/sq cm per sec for Vega and 300,000 erg/sq cm per sec for Eta Boo are estimated and shown to fall within the range of solar coronal X-ray emission. It is concluded that in view of the substantially larger surface areas of these stars, the relatively large total soft X-ray luminosity (as compared with that of the sun) can in both cases be understood as resulting from a moderately active corona, although the Vega observation is in severe conflict with simple models for X-ray emission from single main-sequence stars.

  17. Thermal, structural, and fabrication aspects of diamond windows for high power synchrotron x-ray beamlines

    SciTech Connect

    Khounsary, A.M. ); Phillips, W. )

    1992-01-01

    Recent advances in chemical vapor deposition (CVD) technology have made it possible to produce thin free-standing diamond foils that can be used as the window material in high heat load, synchrotron beamlines. Numerical simulations suggest that these windows can offer an attractive and at times the only altemative to beryllium windows for use in third generation x-ray synchrotron radiation beamlines. Utilization, design, and fabrication aspects of diamond windows for high heat load x-ray beamlines are discussed, as are the microstructure characteristics bearing on diamond's performance in this role. Analytic and numerical results are also presented to provide a basis for the design and testing of such windows.

  18. Micro-structural characterization of materials using synchrotron hard X-ray imaging techniques

    SciTech Connect

    Agrawal, Ashish Singh, Balwant; Kashyap, Yogesh; Sarkar, P. S.; Shukla, Mayank; Sinha, Amar

    2015-06-24

    X-ray imaging has been an important tool to study the materials microstructure with the laboratory based sources however the advent of third generation synchrotron sources has introduced new concepts in X-ray imaging such as phase contrast imaging, micro-tomography, fluorescence imaging and diffraction enhance imaging. These techniques are being used to provide information of materials about their density distribution, porosity, geometrical and morphological characteristics at sub-micron scalewith improved contrast. This paper discusses the development of various imaging techniques at synchrotron based imaging beamline Indus-2 and few recent experiments carried out at this facility.

  19. Synchrontron VUV and Soft X-Ray Radiation Effects on Aluminized Teflon FEP

    NASA Technical Reports Server (NTRS)

    Dever, Joyce A.; Townsend, Jacqueline A.; Gaier, James R.; Jalics, Alice I.

    1998-01-01

    Surfaces of the aluminized Teflon FEP multi-layer thermal insulation on the Hubble Space Telescope (HST) were found to be cracked and curled in some areas at the time of the second servicing, mission in February 1997, 6.8 years after HST was deployed in low Earth orbit (LEO). As part of a test program to assess environmental conditions which would produce embrittlement sufficient to cause cracking of Teflon on HST, samples of Teflon FEP with a backside layer of vapor deposited aluminum were exposed to vacuum ultraviolet (VUV) and soft x-ray radiation of various energies using facilities at the National Synchrotron Light Source. Brookhaven National Laboratory. Samples were exposed to synchrotron radiation of narrow energy bands centered on energies between 69 eV and 1900 eV. Samples were analyzed for ultimate tensile strength and elongation. Results will be compared to those of aluminized Teflon FEP retrieved from HST after 3.6 years and 6.8 years on orbit and will he referenced to estimated HST mission doses of VUV and soft x-ray radiation.

  20. Refraction effects in soft x-ray multilayer blazed gratings.

    PubMed

    Voronov, D L; Salmassi, F; Meyer-Ilse, J; Gullikson, E M; Warwick, T; Padmore, H A

    2016-05-30

    A 2500 lines/mm Multilayer Blazed Grating (MBG) optimized for the soft x-ray wavelength range was fabricated and tested. The grating coated with a W/B4C multilayer demonstrated a record diffraction efficiency in the 2nd blazed diffraction order in the energy range from 500 to 1200 eV. Detailed investigation of the diffraction properties of the grating demonstrated that the diffraction efficiency of high groove density MBGs is not limited by the normal shadowing effects that limits grazing incidence x-ray grating performance. Refraction effects inherent in asymmetrical Bragg diffraction were experimentally confirmed for MBGs. The refraction affects the blazing properties of the MBGs and results in a shift of the resonance wavelength of the gratings and broadening or narrowing of the grating bandwidth depending on diffraction geometry. The true blaze angle of the MBGs is defined by both the real structure of the multilayer stack and by asymmetrical refraction effects. Refraction effects can be used as a powerful tool in providing highly efficient suppression of high order harmonics.

  1. Soft X-ray Imager (SXI) onboard ASTRO-H

    NASA Astrophysics Data System (ADS)

    Hayashida, Kiyoshi; Tsunemi, Hiroshi; Tsuru, Takeshi G.; Dotani, Tadayasu; Nakajima, Hiroshi; Anabuki, Naohisa; Nagino, Ryo; Ueda, Shutaro; Tanaka, Takaaki; Uchida, Hiroyuki; Nobukawa, Masayoshi; Ozaki, Masayuki; Natsukari, Chikara; Hiraga, Junko S.; Tomida, Hiroshi; Kimura, Masashi; Kohmura, Tadayoshi; Murakami, Hiroshi; Mori, Koji; Yamauchi, Makoto; Hatsukade, Isamu; Nishioka, Yusuke; Bamba, Aya; Katada, Shuhei; Nobukawa, Kumiko K.; Iwai, Masachika; Kondo, Keisuke; Takeyoshi, Tukasa; Doty, John P.

    2014-07-01

    Soft X-ray Imager (SXI) is a CCD camera onboard the ASTRO-H satellite which is scheduled to be launched in 2015. The SXI camera contains four CCD chips, each with an imaging area of 31mm x 31 mm, arrayed in mosaic, covering the whole FOV area of 38' x 38'. The CCDs are a P-channel back-illuminated (BI) type with a depletion layer thickness of 200 _m. High QE of 77% at 10 keV expected for this device is an advantage to cover an overlapping energy band with the Hard X-ray Imager (HXI) onboard ASTRO-H. Most of the flight components of the SXI system are completed until the end of 2013 and assembled, and an end-to-end test is performed. Basic performance is verified to meet the requirements. Similar performance is confirmed in the first integration test of the satellite performed in March to June 2014, in which the energy resolution at 5.9 keV of 160 eV is obtained. In parallel to these activities, calibrations using engineering model CCDs are performed, including QE, transmission of a filter, linearity, and response profiles.

  2. Soft-x-ray fragmentation studies of molecular ions

    NASA Astrophysics Data System (ADS)

    Wolf, Andreas; Pedersen, Henrik B.; Lammich, Lutz; Jordon-Thaden, Brandon; Altevogt, Simon; Domesle, Christian; Hergenhahn, Uwe; Förstel, Marko; Heber, Oded

    2010-10-01

    Imaging of photofragments from molecular ions after irradiation by soft x-ray photons has been realized at the ion beam infrastructure TIFF set up at the FLASH facility. Photodissociation of the two-electron system HeH+ at 38.7 eV revealed the electronic excitations and the charge-state ratios for the products of this process, reflecting the non-adiabatic dissociation dynamics through multiple avoided crossings among the HeH+ Rydberg potential curves. Dissociative ionization of the protonated water molecules H3O+ and H5O+2 at 90 eV revealed the main fragmentation pathways after the production of valence vacancies in these ionic species, which include a strong three-body channel with a neutral fragment (OH + H+ + H+) in H3O+ photolysis and a significant two-body fragmentation channel (H3O++ H2O+) in H5O+2 photolysis. The measurements yield absolute cross sections and fragment angular distributions. Increased precision and sensitivity of the technique were realized in recent developments, creating a tool for exploring x-ray excited molecular states under highly controlled target conditions challenging detailed theoretical understanding.

  3. Design and analysis of soft X-ray imaging microscopes

    NASA Technical Reports Server (NTRS)

    Shealy, David L.; Cheng, Wang; Wu, Jiang; Hoover, Richard B.

    1992-01-01

    The spherical Schwarzschild microscope for soft X-ray applications in microscopy and projection lithography consists of two concentric spherical mirrors configured such that the third-order spherical aberration and coma are zero. Since multilayers are used on the mirror substrates for X-ray applications, it is desirable to have only two reflecting surfaces in a microscope. To reduce microscope aberrations and increase the field of view, generalized mirror surface profiles are here considered. Based on incoherent and sine wave modulation transfer function calculations, the object plane resolution of a microscope has been analyzed as a function of the object height and numerical aperture (NA) of the primary for several spherical Schwarzschild, conic, and aspherical Head reflecting two-mirror microscope configurations. The Head microscope with a NA of 0.4 achieves diffraction limited performance for objects with a diameter of 40 microns. Thus, it seems possible to record images with a feature size less than 100 A with a 40x microscope when using 40 A radiation.

  4. A new detector system for low energy X-ray fluorescence coupled with soft X-ray microscopy: First tests and characterization

    NASA Astrophysics Data System (ADS)

    Gianoncelli, Alessandra; Bufon, Jernej; Ahangarianabhari, Mahdi; Altissimo, Matteo; Bellutti, Pierluigi; Bertuccio, Giuseppe; Borghes, Roberto; Carrato, Sergio; Cautero, Giuseppe; Fabiani, Sergio; Giacomini, Gabriele; Giuressi, Dario; Kourousias, George; Menk, Ralf Hendrik; Picciotto, Antonino; Piemonte, Claudio; Rachevski, Alexandre; Rashevskaya, Irina; Stolfa, Andrea; Vacchi, Andrea; Zampa, Gianluigi; Zampa, Nicola; Zorzi, Nicola

    2016-04-01

    The last decades have witnessed substantial efforts in the development of several detector technologies for X-ray fluorescence (XRF) applications. In spite of the increasing trend towards performing, cost-effective and reliable XRF systems, detectors for soft X-ray spectroscopy still remain a challenge, requiring further study, engineering and customization in order to yield effective and efficient systems. In this paper we report on the development, first characterization and tests of a novel multielement detector system based on low leakage current silicon drift detectors (SDD) coupled to ultra low noise custom CMOS preamplifiers for synchrotron-based low energy XRF. This new system exhibits the potential for improving the count rate by at least an order of magnitude resulting in ten-fold shorter dwell time at an energy resolution similar to that of single element silicon drift detectors.

  5. A bend magnet facility for production and application of circularly polarized soft x rays at the Advanced Light Source (abstract)

    NASA Astrophysics Data System (ADS)

    Bustamante, C.; Chen, C. T.; Sette, F.; Howells, M. R.; Hunt, A. J.; Kim, K. J.; Kincaid, B. M.; Maestre, M. F.; Nygren, D. R.; Wong, M.; Snyder, P. A.; Stern, E. A.

    1992-01-01

    The Advanced Light Source (ALS) is a synchrotron radiation facility based on a low-emittance, 1.5-GeV electron storage ring presently under construction at the Lawrence Berkeley Laboratory, U.S.A. Plans are under way to develop a polarized photon facility at the ALS, exploiting the natural polarization properties of the bend magnet synchrotron radiation. The radiation emitted in the plane of the storage ring is linearly polarized, while above and below the plane it is elliptically polarized. We will utilize these properties to obtain circularly polarized soft x rays. A participating research team (PRT A018) has been formed and is proceeding with the design of a high-resolution beamline in the soft x-ray energy region 100-1500 eV. Intense beams of monochromatic, tunable, pulsed, circularly polarized photons will become available. We will discuss the physical characteristics of this polarized soft x-ray source. New investigations in biology, materials science, physics, and chemistry will become accessible. Initial experiments using circularly polarized photons in the soft x-ray region are planned in the areas of differential scattering and absorption from chiral molecules and probing the electronic and magnetic properties of magnetic systems. This work was supported by the U.S. Department of Energy (DE-AC03-76SF00098).

  6. Imaging local electric fields produced upon synchrotron X-ray exposure

    DOE PAGES

    Dettmar, Christopher M.; Newman, Justin A.; Toth, Scott J.; ...

    2014-12-31

    Electron–hole separation following hard X-ray absorption during diffraction analysis of soft materials under cryogenic conditions produces substantial local electric fields visualizable by second harmonic generation (SHG) microscopy. Monte Carlo simulations of X-ray photoelectron trajectories suggest the formation of substantial local electric fields in the regions adjacent to those exposed to X-rays, indicating a possible electric-field–induced SHG (EFISH) mechanism for generating the observed signal. In studies of amorphous vitreous solvents, analysis of the SHG spatial profiles following X-ray microbeam exposure was consistent with an EFISH mechanism. Within protein crystals, exposure to 12-keV (1.033-Å) X-rays resulted in increased SHG in the regionmore » extending ~3 μm beyond the borders of the X-ray beam. Moderate X-ray exposures typical of those used for crystal centering by raster scanning through an X-ray beam were sufficient to produce static electric fields easily detectable by SHG. The X-ray–induced SHG activity was observed with no measurable loss for longer than 2 wk while maintained under cryogenic conditions, but disappeared if annealed to room temperature for a few seconds. In conclusion, these results provide direct experimental observables capable of validating simulations of X-ray–induced damage within soft materials. Additionally, X-ray–induced local fields may potentially impact diffraction resolution through localized piezoelectric distortions of the lattice.« less

  7. Minimally Invasive Coronary Angiography with Monochromatic X-Rays Developmental Studies Utilizing Synchrotron Radiation.

    NASA Astrophysics Data System (ADS)

    Otis, John Noel

    Iodine-containing compounds are used as contrast agents in obtaining X-ray images of blood vessels for medical diagnosis. If the X-ray contrast produced by iodine can be enhanced sufficiently relative to that produced by the intervening body tissues, it becomes possible to obtain images of arteries by introducing the contrast agent into the venous circulation rather than through an arterial catheter directly into the vessel under examination. This prospect is attractive because invasion of the arterial system is the chief cause of the medical complications that are encountered in the application of current angiographic procedures. An imaging system that shows promise of accomplishing this goal for examination of the coronary arteries has been developed for operation in an X-ray beam at the Stanford Synchrotron Radiation Laboratory. Iodine-selective contrast enhancement is achieved by logarithmic subtraction of two images of the same field. One of these images is formed by monochromatic X-rays of energy just above the characteristic iodine K-absorption edge at 33.17 keV, the other by X-rays of energy just below the edge. The computer-controlled imaging system acquires digitized images line by line while scanning the subject through a stationary X-ray beam of linear profile. At present, only synchrotron radiation can provide monochromatic X-ray beams of intensity sufficient to image the small and rapidly moving coronary arteries. Preliminary studies of static phantoms and in vivo studies of dogs establish the feasibility of using synchrotron radiation as the X-ray source for iodine-selective imaging with sensitivity and speed adequate for providing sharp images of coronary arteries after intravenous introduction of contrast agent. Application of the method to human subjects began with imaging studies of three patients in May, 1986.

  8. Optical, UV and soft x-ray transmission of optical blocking layer for the x-ray CCD

    NASA Astrophysics Data System (ADS)

    Kawai, K.; Kohmura, T.; Ikeda, S.; Kaneko, K.; watanabe, T.; Tsunemi, H.; Hayashida, K.; Anabuki, N.; Nakajima, H.; Ueda, S.; Tsuru, T. G.; Dotani, T.; Ozaki, M.; Matsuta, K.; Fujinaga, T.; Kitamoto, S.; Murakami, H.; Hiraga, J.; Mori, K.; ASTRO-H SXI Team

    2012-03-01

    We have newly developed the back-illuminated (BI)-CCD which has an Optical Blocking Layer (OBL) directly coating its X-ray illumination surface with Aluminum-Polyimide-Aluminum instead of Optical Blocking Filter (OBF). OBL is composed of a thin polyimide layer sandwiched by two Al layers. Al and Polyimide has a capability to cut visible light and EUV, respectively. To evaluate the performance of OBL that cut off EUV as well as transmit soft X-ray, we measured the EUV and Soft X-ray transmission of both OBL at various energy range between 15-2000 eV by utilizing beam line located at the Photon Factory in High Energy Accelerator Research Organization. We obtained the EUV transmission to be ~3% at 41eV which is as same as expected transmission from the designed thickness of polyimide layer, and found no significant change of the EUV transmission of polyimide found during 9month. We also obtained the Soft X-ray transmission of OBL, and found the X-ray transmission of OBL was consistent with the result expected from the thickness of OBL. We also measured the Optical transmission of OBL between 500-900 nm to evaluate the performance of Al that cut off optical light, and obtained the optical transmission to be less than 4×10-5.

  9. A Novel Integrating Solid State Detector With Segmentation For Scanning Transmission Soft X-ray Microscopy

    NASA Astrophysics Data System (ADS)

    Feser, Michael; Jacobsen, Chris; Degeronimo, Gianluigi; Rehak, Pavel; Holl, Peter; Strueder, Lothar

    2003-03-01

    Scanning transmission x-ray microscopy (STXM) with soft x-rays has unique detector requirements, which are not readily met by commercially available detectors. For implementation of dark-field and phase contrast imaging modes a segmented detector is needed with the high signal to noise ratio of a counting detector and a high detective quantum efficiency. Since the market for STXM is very small, the development of specialized detector systems relies on the collaboration with detector specialists at research facilities. We report on the successful development of a segmented silicon detector for STXM, which has been carried out in collaboration between the x-ray microscopy research group at SUNY Stony Brook, the instrumentation division at Brookhaven National Laboratory and silicon x-ray detector specialists in Germany. This project illustrates the effectiveness of such arrangements and justifies the support of future efforts in developing dedicated detectors for synchrotron radiation experiments bringing together detector experts and experimenters. The developed detector features eight separate circular segments matched to the STXM geometry. Fast charge integrating electronics have been developed to match the short pixel dwell times in a synchrotron based scanning microscope (in the ms range for the NSLS). The noise level of 5 photons RMS per integration per channel (at 520 eV photon energy) and a 1500 photon capacity (corresponding to the well depth in a CCD detector) is well matched to the characteristics of the experiment. Combining the detector signals in an appropriate way, different imaging modes (i.e. bright field, dark field or phase contrast) can be selected. We discuss recent developments on simultaneous quantitative phase and amplitude contrast imaging using this segmented detector in conjunction with a Fourier filter reconstruction technique.

  10. 2-D soft x-ray arrays in the EAST

    SciTech Connect

    Chen, Kaiyun; Xu, Liqing Hu, Liqun; Duan, Yanmin; Yuan, Yi; Mao, Songtao; Sheng, Xiuli; Zhao, Jinlong; Li, Xueqin

    2016-06-15

    A high spatial and temporal resolution soft x-ray (SXR) imaging diagnostic has been installed in EAST for the study of magnetohydrodynamics activities and core high-Z impurity transport. Up to 122 lines of sight view the poloidal plasma from three directions (two up-down symmetrical horizontal arrays and one vertical array), which renders the diagnostic able to provide detailed tomographic reconstructions under various conditions. Fourier-Bessel method based on flux coordinates was employed for 2-D SXR tomographic reconstruction. Examples of several events measured by SXR diagnostic in EAST are shown, namely the crash patterns of sawtooth, periodical burst of edge localized modes, and the transport of high-Z intrinsic impurities.

  11. G-133: A soft X ray solar telescope

    NASA Astrophysics Data System (ADS)

    Williams, Memorie K.; Campbell, Branton; Roming, Peter W. A.; Spute, Mark K.; Moody, J. Ward

    1992-10-01

    The GOLDHELOX Project, NASA payload number G-133, is a robotic soft x ray solar telescope designed and built by an organization of undergraduate students. The telescope is designed to observe the sun at a wavelength of 171 to 181 A. Since we require observations free from atmospheric interference, the telescope will be launched in a NASA Get-Away-Special (GAS) canister with a Motorized Door Assembly (MDA). In this paper we primarily discuss the most important elements of the telescope itself. We also elaborate on some of the technical difficulties associated with doing good science in space on a small budget (about $100,000) and mention ways in which controlling the instrument environment has reduced the complexity of the system and thus saved us money.

  12. G-133: A soft x ray solar telescope

    NASA Technical Reports Server (NTRS)

    Williams, Memorie K.; Campbell, Branton; Roming, Peter W. A.; Spute, Mark K.; Moody, J. Ward

    1992-01-01

    The GOLDHELOX Project, NASA payload number G-133, is a robotic soft x ray solar telescope designed and built by an organization of undergraduate students. The telescope is designed to observe the sun at a wavelength of 171 to 181 A. Since we require observations free from atmospheric interference, the telescope will be launched in a NASA Get-Away-Special (GAS) canister with a Motorized Door Assembly (MDA). In this paper we primarily discuss the most important elements of the telescope itself. We also elaborate on some of the technical difficulties associated with doing good science in space on a small budget (about $100,000) and mention ways in which controlling the instrument environment has reduced the complexity of the system and thus saved us money.

  13. Soft x-ray undulator for the Siam Photon Source

    SciTech Connect

    Rugmai, S.; Dasri, T.; Prawanta, S.; Siriwattanapaitoon, S.; Kwankasem, A.; Sooksrimuang, V.; Chachai, W.; Suradet, N.; Juthong, N.; Tancharakorn, S.

    2007-01-19

    An undulator for production of intense soft x-rays has been designed for the Siam Photon Source. The construction of the undulator has been completed. It is now being characterized and prepared for installation. The device, named U60, is a pure permanent magnet planar undulator, consisting of 41 magnetic periods, with 60 mm period length. Utilization of the undulator radiation in the photon energy range of 30 - 900 eV is expected. The design studies of the magnetic structure, including investigation of perturbations arising from the magnetic field of the device, their effects on the SPS storage ring and compensation schemes are described. A magnetic measurement system has been constructed for magnetic characterization of the device. Partial results of magnetic measurements are presented.

  14. Divergence measurements of soft x-ray laser beam

    SciTech Connect

    Suckewer, S.; Skinner, C.H.; Kim, D.; Valeo, E.; Voorhees, D.; Wouters, A.

    1986-07-01

    The divergence of the CVI 182 A lasing line generated in a rapidly recombining, magnetically confined plasma column was measured using soft x-ray spectrometers equipped with multichannel detectors. In addition to measurements of the relative divergence, an absolute divergence of approx.9 mrad at a magnetic field of 20 kG and approx.5 mrad at a magnetic field of 35 or 50 kG was obtained by a direct scan of the 182 A axial radiation. Based on this data a peak 182 A intensity of approx.100 kW is obtained. Calculations of the spatial distribution of gain in the plasma were in very good agreement with the experimental data.

  15. Soft X-Ray Observations of the Galactic Halo

    NASA Technical Reports Server (NTRS)

    Shelton, Robin; Kuntz, K. D.

    2003-01-01

    In this project, my co-I (K.D. Kuntz) and I plan to extract the soft X-ray spectrum emitted by the hot gas along a high latitude line of sight. We plan to subtract off the local component (garnered from other observations) in order to isolate the halo component. We then plan to combine this spectral information with the ultraviolet resonance line emission produced by slightly cooler gas along the line of sight and use the two observations as a constraint on models. My co-I, K.D., Kuntz has been working on the determination of the instrumental background. I have not yet drawn any of the funds for this project. I have just moved from J h s Hopkins University to the University of Georgia and anticipate finishing the project while at the University of Georgia.

  16. Soft X-Ray Observations of the Galactic Halo

    NASA Technical Reports Server (NTRS)

    Shelton, Robin; Kuntz, K. D.

    2003-01-01

    In this project, my co-I (K.D. Kuntz) and I plan to extract the soft X-ray spectrum emitted by the hot gas along a high latitude line of sight. We plan to subtract off the local component (garnered from other observations) in order to isolate the halo component. We then plan to combine this spectral information with the ultraviolet resonance line emission produced by slightly cooler gas along the line of sight and use the two observations as a constraint on models. My co-I, K.D., Kuntz has been working on the determination of the instrumental background. I have not yet drawn any of the funds for this project. I have just moved from J h s Hopkins University to the University of Georgia and anticipate finishing the project while at the University of Georgia.

  17. Optical pseudomotors for soft x-ray beamlines

    SciTech Connect

    Pedreira, P. Sics, I.; Sorrentino, A.; Pereiro, E.; Aballe, L.; Foerster, M.; Pérez-Dieste, V.; Escudero, C.; Nicolas, J.

    2016-05-15

    Optical elements of soft x-ray beamlines usually have motorized translations and rotations that allow for the fine alignment of the beamline. This is to steer the photon beam at some positions and to correct the focus on slits or on sample. Generally, each degree of freedom of a mirror induces a change of several parameters of the beam. Inversely, several motions are required to actuate on a single optical parameter, keeping the others unchanged. We define optical pseudomotors as combinations of physical motions of the optical elements of a beamline, which allow modifying one optical parameter without affecting the others. We describe a method to obtain analytic relationships between physical motions of mirrors and the corresponding variations of the beam parameters. This method has been implemented and tested at two beamlines at ALBA, where it is used to control the focus of the photon beam and its position independently.

  18. Soft X-Ray Optics by Pulsed Laser Deposition

    NASA Technical Reports Server (NTRS)

    Fernandez, Felix E.

    1996-01-01

    Mo/Si and C/Co multilayers for soft x-ray optics were designed for spectral regions of interest in possible applications. Fabrication was effected by Pulsed Laser Deposition using Nd:YAG (355 nm) or excimer (248 nm) lasers in order to evaluate the suitability of this technique. Results for Mo/Si structures were not considered satisfactory due mainly to problems with particulate production and target surface modification during Si ablation. These problems may be alleviated by a two-wavelength approach, using separate lasers for each target. Results for C/Co multilayers are much more encouraging, since indication of good layering was observed for extremely thin layers. We expect to continue investigating this possibility. In order to compete with traditional PVD techniques, it is necessary to achieve film coverage uniformity over large enough areas. It was shown that this is feasible, and novel means of achieving it were devised.

  19. Tracing Chromospheric Evaporation in Radio and Soft X-rays

    NASA Technical Reports Server (NTRS)

    Aschwanden, Markus J.

    1997-01-01

    There are three publications in refereed journals and several presentations at scientific conferences resulted from this work, over a period of 6 months during 1995/1996. In the first paper, the discovery of the chromospheric evaporation process at radio wavelengths is described. In the second paper, the radio detection is used to quantify electron densities in the upflowing heated plasma in flare loops, which is then compared with independent other density measurements from soft X-rays, or the plasma frequency of electron beams originating in the acceleration region. In the third paper, the diagnostic results of the chromospheric evaporation process are embedded into a broader picture of a standard flare scenario. Abstracts of these three papers are attached.

  20. The LNLS soft X-ray spectroscopy beamline.

    PubMed

    Tolentino, H; Compagnon-Cailhol, V; Vicentin, F C; Abbate, M

    1998-05-01

    The soft X-ray spectroscopy beamline installed at a bending-magnet source at the LNLS is described. The optics are designed to cover energies from 800 to 4000 eV with good efficiency. The focusing element is a gold-coated toroidal mirror with an angle of incidence of 17 mrad. The UHV double-crystal monochromator has three pairs of crystals, Si (111), InSb (111) and beryl (101;0), that can be selected by a sliding movement. The UHV workstation is equipped with an ion gun, an electron gun, an electron analyser, LEED optics, an open channeltron and a photodiode array. This beamline is intended for photoemission, photoabsorption, reflectivity and dichroism experiments.

  1. Surface Slope Metrology on Deformable Soft X-ray Mirrors

    SciTech Connect

    Yuan, Sheng; Yashchuk, Valeriy V.; Goldberg, Kenneth A.; Celestre, Rich; Church, Matthew; McKinney, Wayne R.; Morrison, Greg; Warwick, Tony

    2010-01-31

    We report on the current state of surface slope metrology on deformable mirrors for soft x-rays at the Advanced Light Source (ALS). While we are developing techniques for in situ at-wavelength tuning, we are refining methods of ex situ visible-light optical metrology to achieve sub-100-nrad accuracy. This paper reports on laboratory studies, measurements and tuning of a deformable test-KB mirror prior to its use. The test mirror was bent to a much different optical configuration than its original design, achieving a 0.38 micro-radian residual slope error. Modeling shows that in some cases, by including the image conjugate distance as an additional free parameter in the alignment, along with the two force couples, fourth-order tangential shape errors (the so-called bird shape) can be reduced or eliminated.

  2. Surface Slope Metrology on Deformable Soft X-ray Mirrors

    SciTech Connect

    Yuan, S.; Yashchuk, V.V.; Goldberg, K.A.; Celestre, R.; Church, M.; McKinney, W.R.; Morrison, G.; Warwick, T.

    2009-09-18

    We report on the current state of surface slope metrology on deformable mirrors for soft x-rays at the Advanced Light Source (ALS). While we are developing techniques for in situ at-wavelength tuning, we are refining methods of ex situvisible-light optical metrology to achieve sub-100-nrad accuracy. This paper reports on laboratory studies, measurements and tuning of a deformable test-KB mirror prior to its use. The test mirror was bent to a much different optical configuration than its original design, achieving a 0.38 micro-radian residual slope error. Modeling shows that in some cases, by including the image conjugate distance as an additional free parameter in the alignment, along with the two force couples, fourth-order tangential shape errors (the so-called bird shape) can be reduced or eliminated.

  3. VUV and soft x-ray spectroscopy of actinides

    SciTech Connect

    Olson, C. G.; Joyce, J. J.; Durakiewicz, T.; Guziewicz, E.

    2004-01-01

    Optical and photoelectron spectroscopies using VUV and Soft X-ray photons are powerful tools for studies of elemental and compound actinides. Large changes in the relative atomic cross sections of the 5f, 6d and sp electrons allow decomposition of the character of the valence bands using photoemission. Resonant enhancement of photoelectrons and Auger electrons at the 5d core threshold further aids the decomposition and gives a measure of elemental specificity. Angle-resolved photoemission can be used to map the momentum dependence of the electronic states. The large changes in relative cross section with photon energy yields further details when the mapping is done at equivalent points in multiple zones. Spectra for well understood rare earth materials will be presented to establish spectral characteristics for known atomic character initial states. These signatures will be applied to the case of USb to investigate f-d hybridization near the Fermi level.

  4. Early Results from the YOHKOH Soft X-ray Telescope

    NASA Astrophysics Data System (ADS)

    Bruner, M. E.; Acton, L. W.; Lemen, J.; Hirayama, T.; Tsuneta, S.

    1992-05-01

    The The Soft X-ray Telescope on the Yohkoh satellite, launched by Japan on August 30, 1992, has proved to be a resounding success. It is providing a wealth of new information and many surprises, both on flares and on the behavior of the solar corona. Performance of the telescope has met or exceed our most optimistic expectations and it appears to be in perfect focus. Unlike the Skylab instruments, the Yohkoh telescope is not limited by a finite supply of film, permitting long sequences of images to be made with relatively high time resolution. Repetition rates for a given exposure / filter combination are typically a few seconds per frame to a few minutes per frame, depending on the selected field size. Movies assembled from long exposure sequences have shown the corona to be even more dynamic than expected. Major re-structuring, involving large fractions of the visible corona, can take place in an hour or two. Smaller regions are even more dynamic, changing almost continuously. Movies, created from long exposure sequences, have demonstrated the fundamental importance of large-scale coronal loops in connecting widely separated regions such that activity in one region quickly affects the physical conditions at remote sites. The images also show that the majority of the loops have nearly constant cross sections along their lengths, rather than one that increases with height. Several X-class flares have been observed; the surprising result is that they do not appear to be very dynamic in soft X-rays. The flare kernels seem to consist of compact loop structures that brighten and then fade without changing size or shape. Bright points are not as prominent as in the Skylab images; a result of using a CCD (a linear detector) rather than film which has a logarithmic response. The other instruments on Yohkoh are producing equally exciting results; it seems clear that the Yohkoh mission will produce many major advances in our knowledge of the flare mechanism.

  5. Rocket Experiment Demonstration of a Soft X-ray Polarimeter

    NASA Astrophysics Data System (ADS)

    Marshall, Herman

    This proposal is the lead proposal. Boston University will submit, via NSPIRES, a Co-I proposal, per instructions for Suborbital proposals for multiple-award. Our scientific goal of the Rocket Experiment Demonstration of a Soft X-ray Polarimeter (REDSoX Polarimeter) is to make the first measurement of the linear X-ray polarization of an extragalactic source in the 0.2-0.8 keV band. The first flight of the REDSoX Polarimeter would target Mk 421, which is commonly modeled as a highly relativistic jet aimed nearly along the line of sight. Such sources are likely to be polarized at a level of 30-60%, so the goal is to obtain a significant detection even if it is as low as 10%. Significant revisions to the models of jets emanating from black holes at the cores of active galaxies would be required if the polarization fraction lower than 10%. We employ multilayer-coated mirrors as Bragg reflectors at the Brewster angle. By matching to the dispersion of a spectrometer, one may take advantage of high multilayer reflectivities and achieve polarization modulation factors over 90%. Using replicated foil mirrors from MSFC and gratings made at MIT, we construct a spectrometer that disperses to three laterally graded multilayer mirrors (LGMLs). The lateral grading changes the wavelength of the Bragg peak for 45 degree reflections linearly across the mirror, matching the dispersion of the spectrometer. By dividing the entrance aperture into six equal sectors, pairs of blazed gratings from opposite sectors are oriented to disperse to the same LGML. The position angles for the LGMLs are 120 degrees to each other. CCD detectors then measure the intensities of the dispersed spectra after reflection and polarizing by the LGMLs, giving the three Stokes parameters needed to determine the source polarization. We will rely on components whose performance has been verified in the laboratory or in space. The CCD detectors are based on Chandra and Suzaku heritage. The mirror fabrication team

  6. Crystal spectroscopy of X-ray synchrotron source brightness

    NASA Astrophysics Data System (ADS)

    Als-Nielsen, Jens; Kjaer, Kristian

    1992-12-01

    Photon intensities in a monochromatic beam obtained by a horizontal Bragg reflection of synchrotron radiation by a monochromator crystal are compared for the three perfect crystals: silicon and germanium in symmetric (111) reflection and Diamond (C∗) in asymmetric (111) transmission geometry. Consistent results are obtained within relative bandwidths spanning a factor of 50 from Si(333) to Ge(111) and within a wavelength range form 0.4 Å to 1.6 Å. Results using a mosaic Be crystal within the same wavelength range depend in this work on a model of the mosaicity of the Be crystal. However, if the reflectivity of the Be crystal is determined experimentally for a few selected wavelengths, it is not necessary to invoke a mosaic model and a Be crystal may serve the purpose of characterizing the synchrotron beam as well as a perfect crystal. Thin diamond and beryllium crystals in transmission are particularly convenient for spectroscopy of very powerful beams from third generation synchrotron sources, because these low-Z elements absorb only a tiny fraction of the beam power.

  7. Quantum-dot-array diffraction grating with single order diffraction property for soft x-ray region

    SciTech Connect

    Kuang Longyu; Wang Chuanke; Wang Zhebin; Cao Leifeng; Liu Shenye; Ding Yongkun; Zhu Xiaoli; Xie Changqing

    2010-07-15

    A gold transmission grating is used routinely to disperse the x-ray spectrum at the Z soft x-ray facility to measure the spectrum and temporal history of the absolute soft x-ray power emitted from z-pinch and hohlraum radiation sources. A quantum-dot-array diffraction grating (QDADG) of 250 lines/mm for soft x-ray is designed and fabricated for the first time according to the principle of binary sinusoidal transmission grating. The diffraction efficiencies of the grating are measured in the 150-300 eV photon energy range on the Beamline 3W1B of Beijing Synchrotron Radiation Facility. This article describes the basic concept and calibration techniques and presents calibration results. It is shown that the 250 lines/mm QDADG can be used to disperse light without higher-order diffractions in soft x-ray range, and the diffraction efficiencies of this grating are nearly constant (about 25%), which is beneficial in the spectrum analysis.

  8. Search for soft X-ray emission from SN 1987A with a CCD X-ray imaging spectrometer

    NASA Technical Reports Server (NTRS)

    Burrows, D. N.; Nousek, J. A.; Berthiaume, G. D.; Garmire, G. P.

    1989-01-01

    The results of soft X-ray observations of SN 1987A over the energy band 0.65-2.0 keV are reported. The upper limits on the soft X-ray flux are inconsistent with an extrapolation of the spectrum measured by the Ginga Satellite to the energy band and require a turnover in the X-ray spectrum between 2 and 4 keV. If this turnover is due to absorption by intervening material, a neutral column density associated with the supernova of at least 2.8 x 10 to the 21st/sq cm is required. The background rate for the Texas Instruments 800 x 800 pixel CCD, measured between 150 and 285 km altitude, was 1.1 counts/sq cm s. The background spectrum has a broad peak at 350 electrons, corresponding to charge deposited in the detector by minimally ionizing particles.

  9. Single-optical-element soft-x-ray interferometry with a laser-plasma x-ray source.

    PubMed

    Vogt, Ulrich; Lindblom, Magnus; Jansson, Per A C; Tuohimaa, Tomi T; Holmberg, Anders; Hertz, Hans M; Wieland, Marek; Wilhein, Thomas

    2005-08-15

    We report on a compact interferometer for the water-window soft-x-ray range that is suitable for operation with laser-plasma sources. The interferometer consists of a single diffractive optical element that focuses impinging x rays to two focal spots. The light from these two secondary sources forms the interference pattern. The interferometer was operated with a liquid-nitrogen jet laser-plasma source at lambda=2.88 nm. Scalar wave-field propagation was used to simulate the interference pattern, showing good correspondence between theoretical and experimental results. The diffractive optical element can simultaneously be used as an imaging optic, and we demonstrate soft-x-ray microscopy with interferometric contrast enhancement of a phase object.

  10. Tin-polyimide and indium-polyimide thin-film composites as soft X-ray bandpass filters

    NASA Technical Reports Server (NTRS)

    Powell, Stephen F.; Allen, Maxwell J.; Willis, Thomas D.

    1993-01-01

    A tin-polyimide and an indium-polyimide soft X-ray bandpass filter were fabricated with thicknesses of 1400 and 1750 A for the metal and polyimide components, respectively. The transmission of each filter was measured at the Stanford Synchrotron Radiation Laboratory. The transmission of the tin-polyimide filter was found to be about 40 percent for radiation with wavelengths between 60 and 80 A. The transmission of the indium-polyimide filter was greater than 40 percent between 70 and 90 A. The indium was about 5 percent more transmissive than the tin and attained a maximum transmission of about 48 percent at 76 A. Such filters have potential applications to soft X-ray telescopes that operate in this region. They might also be of interest to investigators who work with X-ray microscopes that image live biological specimens in the 23-44-A water window.

  11. Tin-polyimide and indium-polyimide thin-film composites as soft X-ray bandpass filters

    NASA Technical Reports Server (NTRS)

    Powell, Stephen F.; Allen, Maxwell J.; Willis, Thomas D.

    1993-01-01

    A tin-polyimide and an indium-polyimide soft X-ray bandpass filter were fabricated with thicknesses of 1400 and 1750 A for the metal and polyimide components, respectively. The transmission of each filter was measured at the Stanford Synchrotron Radiation Laboratory. The transmission of the tin-polyimide filter was found to be about 40 percent for radiation with wavelengths between 60 and 80 A. The transmission of the indium-polyimide filter was greater than 40 percent between 70 and 90 A. The indium was about 5 percent more transmissive than the tin and attained a maximum transmission of about 48 percent at 76 A. Such filters have potential applications to soft X-ray telescopes that operate in this region. They might also be of interest to investigators who work with X-ray microscopes that image live biological specimens in the 23-44-A water window.

  12. Contemporary X-ray electron-density studies using synchrotron radiation

    PubMed Central

    Jørgensen, Mads R. V.; Hathwar, Venkatesha R.; Bindzus, Niels; Wahlberg, Nanna; Chen, Yu-Sheng; Overgaard, Jacob; Iversen, Bo B.

    2014-01-01

    Synchrotron radiation has many compelling advantages over conventional radiation sources in the measurement of accurate Bragg diffraction data. The variable photon energy and much higher flux may help to minimize critical systematic effects such as absorption, extinction and anomalous scattering. Based on a survey of selected published results from the last decade, the benefits of using synchrotron radiation in the determination of X-ray electron densities are discussed, and possible future directions of this field are examined. PMID:25295169

  13. Combining operando synchrotron X-ray tomographic microscopy and scanning X-ray diffraction to study lithium ion batteries

    PubMed Central

    Pietsch, Patrick; Hess, Michael; Ludwig, Wolfgang; Eller, Jens; Wood, Vanessa

    2016-01-01

    We present an operando study of a lithium ion battery combining scanning X-ray diffraction (SXRD) and synchrotron radiation X-ray tomographic microscopy (SRXTM) simultaneously for the first time. This combination of techniques facilitates the investigation of dynamic processes in lithium ion batteries containing amorphous and/or weakly attenuating active materials. While amorphous materials pose a challenge for diffraction techniques, weakly attenuating material systems pose a challenge for attenuation-contrast tomography. Furthermore, combining SXRD and SRXTM can be used to correlate processes occurring at the atomic level in the crystal lattices of the active materials with those at the scale of electrode microstructure. To demonstrate the benefits of this approach, we investigate a silicon powder electrode in lithium metal half-cell configuration. Combining SXRD and SRXTM, we are able to (i) quantify the dissolution of the metallic lithium electrode and the expansion of the silicon electrode, (ii) better understand the formation of the Li15Si4 phase, and (iii) non-invasively probe kinetic limitations within the silicon electrode. A simple model based on the 1D diffusion equation allows us to qualitatively understand the observed kinetics and demonstrates why high-capacity electrodes are more prone to inhomogeneous lithiation reactions. PMID:27324109

  14. Discovery of Soft X-Ray Emission From Io, Europa and the Io Plasma Torus

    NASA Technical Reports Server (NTRS)

    Elsner, R. F.; Gladstone, G. R.; Waite, J. H.; Crary, F. J.; Howell, R. R.; Johnson, R. E.; Ford, P. G.; Metzger, A. E.; Hurley, K. C.; Feigelson, E. D.; Six, N. Frank (Technical Monitor)

    2001-01-01

    We report the discovery of soft (0.25 - 2 keV) x-ray emission from the moons Io and Europa, probably Ganymede, and from the Io Plasma Torus (IPT). Bombardment by energetic (greater than 10 keV) H, O, and S ions from the region of the IPT seems the likely source of the x-ray emission from the Galilean moons. According to our estimates, fluorescent x-ray emission excited by solar x-rays, even during flares from the active Sun, charge-exchange processes, previously invoked to explain Jupiter's x-ray aurora and cometary x-ray emission, and ion stripping by dust grains fall to account for the observed emission. On the other hand, bremsstrahlung emission of soft X-rays from non-thermal electrons in the few hundred to few thousand eV range may account for a substantial fraction of the observed x-ray flux from the IPT.

  15. EUV and Soft X-Ray Emissions From Comets

    NASA Astrophysics Data System (ADS)

    Krasnopolsky, V. A.

    2001-05-01

    We analyzed 8 observations of comets with the Extreme Ultraviolet Explorer (EUVE). A soft X-ray camera in the range of 97-165 eV FWHM with a peak effective area of 28 cm2 and three spectrometers at 80-180, 170-360, and 300-720 Å with peak effective areas of 2.1, 0.5, and 0.8 cm2, respectively, were used for those observations. The detection limit of the X-ray camera corresponds to the X-ray luminosity of 1.9x 1014 Δ 2 erg s-1 for photon energy ɛ > 100 eV. (Δ is the geocentric distance in AU.) Five comets were detected with the X-ray camera: Hyakutake, Borrelly, d'Arrest, pre- and postperihelion Hale-Bopp. Their images reveal a crescent-like structure with peak brightness offsets from the nuclei between the sunward and comet orbital velocity directions. X-ray luminosities and their spatial distributions were determined from the observations. The measured luminosities are in excellent correlation with gas production rates in comets, resulting in the efficiency of (6.4 +/- 0.9)x 10-5 AU3/2 in the range of 97-165 eV. Correlation with dust production rates is poor, and this favor a gas-related excitation process. The peak brightnesses scaled to r2 are constant and equal to 26+/- 9 millirayleighs. This means that comae are optically or collisionally thick near the brightness centers. Of a few suggested excitation mechanisms, only charge exchange between solar wind heavy ions and cometary neutrals agrees with both these facts. The EUVE spectra of comets Hale-Bopp and Hyakutake have been analyzed. Due to the close flyby of Hyakutake at 0.1 AU, its spectra are of exceptionally high quality and exceed the currently published spectra of comets by a factor of 3 in resolving power and by two orders of magnitude in photon statistics. The spectra reveal for the first time the emission lines of multiple charged ions which are brought to the comet by the solar wind and excited in charge exchange with cometary neutral species. The most prominent lines are O4+ 215 Å, C4+ 249

  16. Depth Probing Soft X-ray Microprobe (DPSXRM) for High Resolution Probing of Earth's Microstructural Samples

    NASA Astrophysics Data System (ADS)

    Dikedi, P. N.

    2015-12-01

    The Cambrian explosion; occurrence of landslides in very dry weather conditions; rockslides; dead, shriveled-up and crumbled leaves possessing fossil records with the semblance of well preserved, flat leaves; abundance of trilobite tracks in lower and higher rock layers; and sailing stones are enigmas demanding demystifications. These enigmas could be elucidated when data on soil structure, texture and strength are provided by some device with submicrometre accuracy; for these and other reasons, the design of a Depth Probing Soft X-ray Microprobe (DPSXRM), is being proposed; it is expected to deliver soft X-rays, at spatial resolution, ϛ≥600nm and to probe at the depth of 0.5m in 17s. The microprobe is portable compared to a synchrotron radiation facility (Diamond Light Source has land size of 43,300m2); spatial resolution,ϛ , of the DPSXRM surpasses those of the X-ray Fluorescence microanalysis (10µm), electron microprobe (1-3µm) and ion microprobe (5->30µm); the DPSXRM has allowance for multiple targets. Vanadium and Manganese membranes are proposed owing to respective 4.952KeV VKα1 and 5.899KeV MnKα1 X-rays emitted, which best suits micro-probing of Earth's microstructural samples. Compound systems like the Kirk-Patrick and Baez and Wolter optics, aspheric mirrors like elliptical and parabolic optics, small apertures and Abbe sine condition are employed to reduce or remove astigmatism, obliquity, comatic and spherical aberrations—leading to good image quality. Results show that 5.899KeV MnKα1 and 4.952KeV VKα1 soft X-rays will travel a distance of 2.75mm to form circular patches of radii 2.2mm and 2.95mm respectively. Zone plate with nth zone radius of 1.5mm must be positioned 1.5mm and 2mm from the electron gun if circular patches must be formed from 4.952KeV VKα1 and 5.899KeV MnKα1 soft X-rays respectively. The focal lengths of 0.25μm≤ƒ≤1.50μm and 0.04μm≤ƒ≤0.2μm covered by 4.952KeV VKα1 and 5.899KeV Mn Kα1 soft X-Rays, will

  17. Biomedical elemental analysis and imaging using synchrotron x-ray microscopy

    SciTech Connect

    Jones, K.W.; Gordon, B.M.; Schidlovsky, G.; Spanne, P.; Dejun, Xue ); Bockman, R.S. ); Saubermann, A.J. . Health Science Center)

    1990-01-01

    The application of synchrotron x-ray microscopy to biomedical research is currently in progress at the Brookhaven National Synchrotron Light Source (NSLS). The current status of the x-ray microscope (XRM) is reviewed from a technical standpoint. Some of the items considered are photon flux, spatial resolution, quantitation, minimum detection limits, and beam-induced specimen damage. Images can be produced by measurement of fluorescent x rays or of the attenuation of the incident beam by the specimen. Maps of the elemental distributions or linear attenuation of the incident beam by the specimen. Maps of the elemental distributions or linear attenuation coefficients can be made by scanning the specimen past the beam. Computed microtomography (CMT) can be used for non- destructive images through the specimen in either the emission or absorption mode. Examples of measurements made with the XRM are given.

  18. High-energy synchrotron X-ray radiography of shock-compressed materials

    NASA Astrophysics Data System (ADS)

    Rutherford, Michael E.; Chapman, David J.; Collinson, Mark A.; Jones, David R.; Music, Jasmina; Stafford, Samuel J. P.; Tear, Gareth R.; White, Thomas G.; Winters, John B. R.; Drakopoulos, Michael; Eakins, Daniel E.

    2015-06-01

    This presentation will discuss the development and application of a high-energy (50 to 250 keV) synchrotron X-ray imaging method to study shock-compressed, high-Z samples at Beamline I12 at the Diamond Light Source synchrotron (Rutherford-Appleton Laboratory, UK). Shock waves are driven into materials using a portable, single-stage gas gun designed by the Institute of Shock Physics. Following plate impact, material deformation is probed in-situ by white-beam X-ray radiography and complimentary velocimetry diagnostics. The high energies, large beam size (13 x 13 mm), and appreciable sample volumes (~ 1 cm3) viable for study at Beamline I12 compliment existing in-house pulsed X-ray capabilities and studies at the Dynamic Compression Sector. The authors gratefully acknowledge the ongoing support of Imperial College London, EPSRC, STFC and the Diamond Light Source, and AWE Plc.

  19. Development rate of PMMA exposed to synchrotron x-ray radiation for LIGA applications

    NASA Astrophysics Data System (ADS)

    McNamara, Shamus

    2011-01-01

    This paper investigates the development rate of poly(methyl methacrylate) (PMMA) after it is exposed to synchrotron x-ray radiation. The x-ray exposures were performed at both Synchrotron Radiation Center and Brookhaven National Laboratories. The development rate of PMMA in a variety of developers was measured as a function of absorbed x-ray dose (J cm-3). The development rate of four different types of PMMA was investigated: unexposed 950k PMMA, Cryo GMS PMMA, Goodfellow CQ PMMA, and Crosslinked PMMA. It was found that the development rate is the same for all types of PMMA studied. The temperature dependence of one developer, GG developer, was studied in detail and it is shown that the selectivity of exposed to unexposed PMMA increases as the temperature is reduced. This work was performed in part at the University of Wisconsin.

  20. ON THE X-RAY OUTBURSTS OF TRANSIENT ANOMALOUS X-RAY PULSARS AND SOFT GAMMA-RAY REPEATERS

    SciTech Connect

    Cal Latin-Small-Letter-Dotless-I skan, Sirin; Ertan, Uenal

    2012-10-20

    We show that the X-ray outburst light curves of four transient anomalous X-ray pulsars (AXPs) and soft gamma-ray repeaters (SGRs), namely, XTE J1810-197, SGR 0501+4516, SGR 1627-41, and CXOU J164710.2-455216, can be produced by the fallback disk model that was also applied to the outburst light curves of persistent AXPs and SGRs in our earlier work. The model solves the diffusion equation for the relaxation of a disk that has been pushed back by a soft gamma-ray burst. The sets of main disk parameters used for these transient sources are very similar to each other and to those employed in our earlier models of persistent AXPs and SGRs. There is a characteristic difference between the X-ray outburst light curves of transient and persistent sources. This can be explained by the differences in the disk surface density profiles of the transient and persistent sources in quiescence indicated by their quiescent X-ray luminosities. Our results imply that a viscous disk instability operating at a critical temperature in the range of {approx}1300-2800 K is a common property of all fallback disks around AXPs and SGRs. The effect of the instability is more pronounced and starts earlier for the sources with lower quiescent luminosities, which leads to the observable differences in the X-ray enhancement light curves of transient and persistent sources. A single active disk model with the same basic disk parameters can account for the enhancement phases of both transient and persistent AXPs and SGRs. We also present a detailed parameter study to show the effects of disk parameters on the evolution of the X-ray luminosity of AXPs and SGRs in the X-ray enhancement phases.

  1. Photosynthesis and structure of electroless Ni-P films by synchrotron x-ray irradiation

    SciTech Connect

    Hsu, P.-C.; Wang, C.-H.; Yang, T.-Y.; Hwu, Y.-K.; Lin, C.-S.; Chen, C.-H.; Chang, L.-W.; Seol, S.-K.; Je, J.-H.; Margaritondo, G.

    2007-05-15

    The authors describe an electroless deposition method for thin films, based on the irradiation by an x-ray beam emitted by a synchrotron source. Specifically, Ni-P films were deposited at room temperature. This synthesis is a unique combination of photochemical and electrochemical processes. The influence of the pH value on the formation and structural properties of the films was examined by various characterization tools including scanning electron microscopy, x-ray diffraction, and x-ray absorption spectroscopy. Real time monitoring of the deposition process by coherent x-ray microscopy reveals that the formation of hydrogen bubbles leads to a self-catalysis effect without a preexisting catalyst. The mechanisms underlying the deposition process are discussed in details.

  2. Progress Towards A Dedicated Synchrotron Radiation Source For Ultrafast X-Ray Science

    NASA Astrophysics Data System (ADS)

    Lidia, Steve

    2002-03-01

    We present progress towards the design of a femtosecond synchrotron radiation x-ray source based on a flat-beam rf gun and a recirculating superconducting linac that provides beam to an array of undulators and bend magnets. Optical pulse durations of <100 fs are obtained by a combination of electron pulse compression, transverse temporal correlation of the electrons, and x-ray pulse compression. After an introduction and initial scientific motivation, we cover the following aspects of the design: layout and lattice, ultra-fast x-ray pulse production, flat electron-beam production, the rf gun, rf systems, cryogenic systems, collective effects, photon production, and synchronization of x-ray and laser pulses. We conclude with a summary of issues and areas of development that remain to be addressed.

  3. Initial feasibility study of a dedicated synchrotron radiation light source for ultrafast X-ray science

    SciTech Connect

    Corlett, John N.; DeSantis, S.; Hartman, N.; Heimann, P.; LaFever, R.; Li, D.; Padmore, H.; Rimmer, R.; Robinson, K.; Schoenlein, R.; Tanabe, J.; Wang, S.; Zholents, A.; Kairan, D.

    2001-10-26

    We present an initial feasibility summary of a femtosecond synchrotron radiation x-ray source based on a flat-beam rf gun and a recirculating superconducting linac that provides beam to an array of undulators and bend magnets. Optical pulse durations of < 100 fs are obtained by a combination of electron pulse compression, transverse temporal correlation of the electrons, and x-ray pulse compression. After an introduction and initial scientific motivation, we cover the following aspects of the design: layout and lattice, ultra-fast x-ray pulse production, flat electron-beam production, the rf gun, rf systems, cryogenic systems, collective effects, photon production, and synchronization of x-ray and laser pulses. We conclude with a summary of issues and areas of development that remain to be addressed.

  4. Hard X-ray nanofocusing at low-emittance synchrotron radiation sources

    PubMed Central

    Schroer, Christian G.; Falkenberg, Gerald

    2014-01-01

    X-ray scanning microscopy relies on intensive nanobeams generated by imaging a highly brilliant synchrotron radiation source onto the sample with a nanofocusing X-ray optic. Here, using a Gaussian model for the central cone of an undulator source, the nanobeam generated by refractive X-ray lenses is modeled in terms of size, flux and coherence. The beam properties are expressed in terms of the emittances of the storage ring and the lateral sizes of the electron beam. Optimal source parameters are calculated to obtain efficient and diffraction-limited nanofocusing. With decreasing emittance, the usable fraction of the beam for diffraction-limited nanofocusing experiments can be increased by more than two orders of magnitude compared with modern storage ring sources. For a diffraction-limited storage ring, nearly the whole beam can be focused, making these sources highly attractive for X-ray scanning microscopy. PMID:25177988

  5. Comparison of synchrotron x-ray microanalysis with electron and proton microscopy for individual particle analysis

    SciTech Connect

    Janssens, K.H.; van Langevelde, F.; Adams, F.C.; Vis, R.D.; Sutton, S.R.; Rivers, M.L.; Jones, K.W.; Bowen, D.K.

    1991-12-31

    This paper is concerned with the evaluation of the use of synchrotron/radiation induced x-ray fluorescences ({mu}-SRXRF) as implemented at two existing X-ray microprobes for the analysis of individual particles. As representative environmental particulates, National Institutes of Science and Technology (NIST) K227, K309, K441 and K961 glass microspheres were analyzed using two types of X-ray micro probes: the white light microprobe at beamline X26A of the monochromatic (15 keV) X-ray microprobe at station 7.6 of the SRS. For reference, the particles were also analyzed with microanalytical techniques more commonly employed for individual particles analysis such as EPMA and micro-PIXE.

  6. Comparison of synchrotron x-ray microanalysis with electron and proton microscopy for individual particle analysis

    SciTech Connect

    Janssens, K.H.; van Langevelde, F.; Adams, F.C. ); Vis, R.D. ); Sutton, S.R.; Rivers, M.L. ); Jones, K.W. ); Bowen, D.K. )

    1991-01-01

    This paper is concerned with the evaluation of the use of synchrotron/radiation induced x-ray fluorescences ({mu}-SRXRF) as implemented at two existing X-ray microprobes for the analysis of individual particles. As representative environmental particulates, National Institutes of Science and Technology (NIST) K227, K309, K441 and K961 glass microspheres were analyzed using two types of X-ray micro probes: the white light microprobe at beamline X26A of the monochromatic (15 keV) X-ray microprobe at station 7.6 of the SRS. For reference, the particles were also analyzed with microanalytical techniques more commonly employed for individual particles analysis such as EPMA and micro-PIXE.

  7. CCD (charge-coupled device) sensors in synchrotron x-ray detectors

    SciTech Connect

    Strauss, M.G.; Naday, I.; Sherman, I.S.; Kraimer, M.R.; Westbrook, E.M.; Zaluzec, N.J.

    1987-01-01

    The intense photon flux from advanced synchrotron light sources, such as the 7-GeV synchrotron being designed at Argonne, require integrating-type detectors. Charge-coupled devices (CCDs) are well suited as synchrotron x-ray detectors. When irradiated indirectly via a phosphor followed by reducing optics, diffraction patterns of 100 cm/sup 2/ can be imaged on a 2 cm/sup 2/ CCD. With a conversion efficiency of approx.1 CCD electron/x-ray photon, a peak saturation capacity of >10/sup 6/ x rays can be obtained. A programmable CCD controller operating at a clock frequency of 20 MHz has been developed. The readout rate is 5 x 10/sup 6/ pixels/s and the shift rate in the parallel registers is 10/sup 6/ lines/s. The test detector was evaluated in two experiments. In protein crystallography diffraction patterns have been obtained from a lysozyme crystal using a conventional rotating anode x-ray generator. Based on these results we expect to obtain at a synchrotron diffraction images at the rate of approx.1 frame/s or a complete 3-dimensional data set from a single crystal in approx.2 min. 16 refs., 16 figs., 2 tabs.

  8. Fracture mechanics by three-dimensional crack-tip synchrotron X-ray microscopy

    PubMed Central

    Withers, P. J.

    2015-01-01

    To better understand the relationship between the nucleation and growth of defects and the local stresses and phase changes that cause them, we need both imaging and stress mapping. Here, we explore how this can be achieved by bringing together synchrotron X-ray diffraction and tomographic imaging. Conventionally, these are undertaken on separate synchrotron beamlines; however, instruments capable of both imaging and diffraction are beginning to emerge, such as ID15 at the European Synchrotron Radiation Facility and JEEP at the Diamond Light Source. This review explores the concept of three-dimensional crack-tip X-ray microscopy, bringing them together to probe the crack-tip behaviour under realistic environmental and loading conditions and to extract quantitative fracture mechanics information about the local crack-tip environment. X-ray diffraction provides information about the crack-tip stress field, phase transformations, plastic zone and crack-face tractions and forces. Time-lapse CT, besides providing information about the three-dimensional nature of the crack and its local growth rate, can also provide information as to the activation of extrinsic toughening mechanisms such as crack deflection, crack-tip zone shielding, crack bridging and crack closure. It is shown how crack-tip microscopy allows a quantitative measure of the crack-tip driving force via the stress intensity factor or the crack-tip opening displacement. Finally, further opportunities for synchrotron X-ray microscopy are explored. PMID:25624521

  9. Fracture mechanics by three-dimensional crack-tip synchrotron X-ray microscopy.

    PubMed

    Withers, P J

    2015-03-06

    To better understand the relationship between the nucleation and growth of defects and the local stresses and phase changes that cause them, we need both imaging and stress mapping. Here, we explore how this can be achieved by bringing together synchrotron X-ray diffraction and tomographic imaging. Conventionally, these are undertaken on separate synchrotron beamlines; however, instruments capable of both imaging and diffraction are beginning to emerge, such as ID15 at the European Synchrotron Radiation Facility and JEEP at the Diamond Light Source. This review explores the concept of three-dimensional crack-tip X-ray microscopy, bringing them together to probe the crack-tip behaviour under realistic environmental and loading conditions and to extract quantitative fracture mechanics information about the local crack-tip environment. X-ray diffraction provides information about the crack-tip stress field, phase transformations, plastic zone and crack-face tractions and forces. Time-lapse CT, besides providing information about the three-dimensional nature of the crack and its local growth rate, can also provide information as to the activation of extrinsic toughening mechanisms such as crack deflection, crack-tip zone shielding, crack bridging and crack closure. It is shown how crack-tip microscopy allows a quantitative measure of the crack-tip driving force via the stress intensity factor or the crack-tip opening displacement. Finally, further opportunities for synchrotron X-ray microscopy are explored.

  10. Variable magnification with Kirkpatrick-Baez optics for synchrotron X-ray microscopy

    DOE PAGES

    Jach, Terrence; Bakulin, Alex S.; Durbin, Stephen M.; ...

    2006-05-01

    In this study, we describe the distinction between the operation of a short focal length x-ray microscope forming a real image with a laboratory source (convergent illumination) and with a highly collimated intense beam from a synchrotron light source (Kohler illumination).

  11. Atomic physics with hard X-rays from high brilliance synchrotron light sources

    SciTech Connect

    Southworth, S.; Gemmell, D.

    1996-08-01

    A century after the discovery of x rays, the experimental capability for studying atomic structure and dynamics with hard, bright synchrotron radiation is increasing remarkably. Tempting opportunities arise for experiments on many-body effects, aspects of fundamental photon-atom interaction processes, and relativistic and quantum-electrodynamic phenomena. Some of these possibilities are surveyed in general terms.

  12. Status of the X-Ray Absorption Spectroscopy (XAS) Beamline at the Australian Synchrotron

    NASA Astrophysics Data System (ADS)

    Glover, C.; McKinlay, J.; Clift, M.; Barg, B.; Boldeman, J.; Ridgway, M.; Foran, G.; Garret, R.; Lay, P.; Broadbent, A.

    2007-02-01

    We present herein the current status of the X-ray Absorption Spectroscopy (XAS) Beamline at the 3 GeV Australian Synchrotron. The optical design and performance, details of the insertion device (Wiggler), end station capabilities and construction and commissioning timeline are given.

  13. High counting rates of x-ray photon detection using APD detectors on synchrotron machines

    SciTech Connect

    Kakuno, E. M.; Giacomolli, B. A.; Scorzato, C. R.

    2012-05-17

    In this work we show the results of 10 x 10 mm{sup 2} Si-APD detector's test with guard ring detecting x-rays. The result of mapping surface is also exhibited. We show and discuss the difficulty of single photon detection in high counting rate experiments in synchrotrons machines.

  14. X-ray photonic microsystems for the manipulation of synchrotron light

    PubMed Central

    Mukhopadhyay, D.; Walko, D. A.; Jung, I. W.; Schwartz, C. P.; Wang, Jin; López, D.; Shenoy, G. K.

    2015-01-01

    Photonic microsystems played an essential role in the development of integrated photonic devices, thanks to their unique spatiotemporal control and spectral shaping capabilities. Similar capabilities to markedly control and manipulate X-ray radiation are highly desirable but practically impossible due to the massive size of the silicon single-crystal optics currently used. Here we show that micromechanical systems can be used as X-ray optics to create and preserve the spatial, temporal and spectral correlation of the X-rays. We demonstrate that, as X-ray reflective optics they can maintain the wavefront properties with nearly 100% reflectivity, and as a dynamic diffractive optics they can generate nanosecond time windows with over 100-kHz repetition rates. Since X-ray photonic microsystems can be easily incorporated into lab-based and next-generation synchrotron X-ray sources, they bring unprecedented design flexibility for future dynamic and miniature X-ray optics for focusing, wavefront manipulation, multicolour dispersion, and pulse slicing. PMID:25940542

  15. X-ray photonic microsystems for the manipulation of synchrotron light

    SciTech Connect

    Mukhopadhyay, D.; Walko, D. A.; Jung, I. W.; Schwartz, C. P.; Wang, Jin; López, D.; Shenoy, G. K.

    2015-05-05

    In this study, photonic microsystems played an essential role in the development of integrated photonic devices, thanks to their unique spatiotemporal control and spectral shaping capabilities. Similar capabilities to markedly control and manipulate X-ray radiation are highly desirable but practically impossible due to the massive size of the silicon single-crystal optics currently used. Here we show that micromechanical systems can be used as X-ray optics to create and preserve the spatial, temporal and spectral correlation of the X-rays. We demonstrate that, as X-ray reflective optics they can maintain the wavefront properties with nearly 100% reflectivity, and as a dynamic diffractive optics they can generate nanosecond time windows with over 100-kHz repetition rates. Since X-ray photonic microsystems can be easily incorporated into lab-based and next-generation synchrotron X-ray sources, they bring unprecedented design flexibility for future dynamic and miniature X-ray optics for focusing, wavefront manipulation, multicolour dispersion, and pulse slicing.

  16. X-ray photonic microsystems for the manipulation of synchrotron light

    DOE PAGES

    Mukhopadhyay, D.; Walko, D. A.; Jung, I. W.; ...

    2015-05-05

    In this study, photonic microsystems played an essential role in the development of integrated photonic devices, thanks to their unique spatiotemporal control and spectral shaping capabilities. Similar capabilities to markedly control and manipulate X-ray radiation are highly desirable but practically impossible due to the massive size of the silicon single-crystal optics currently used. Here we show that micromechanical systems can be used as X-ray optics to create and preserve the spatial, temporal and spectral correlation of the X-rays. We demonstrate that, as X-ray reflective optics they can maintain the wavefront properties with nearly 100% reflectivity, and as a dynamic diffractivemore » optics they can generate nanosecond time windows with over 100-kHz repetition rates. Since X-ray photonic microsystems can be easily incorporated into lab-based and next-generation synchrotron X-ray sources, they bring unprecedented design flexibility for future dynamic and miniature X-ray optics for focusing, wavefront manipulation, multicolour dispersion, and pulse slicing.« less

  17. Chemically selective soft x-ray patterning of polymers

    SciTech Connect

    Wang, J.; Stover, H.D.; Hitchcock, A.P.; Tyliszczak, T.

    2007-06-19

    The chemically selective modification of polymer mixtures by monochromated soft X-rays has been explored using the high-brightness fine-focused 50 nm beam of a scanning transmission X-ray microscope. Four different polymer systems were examined: a polymethylmethacrylate (PMMA) polyacrylonitrile (PAN) bilayer film; a PMMA-blend-PAN microphase-separated film; a poly(MMA-co-AN) copolymer film; and a poly(ethyl cyanoacrylate) homopolymer film. A high level of chemically selective modification was achieved for the PMMA/PAN bilayer; in particular, irradiation at 288.45 eV selectively removed the carbonyl group from PMMA while irradiation at 286.80 eV selectively reduced the nitrile group of PAN, even when these irradiations were carried out at the same (x,y) position of the sample. In the last two homogeneous polymer systems, similar amounts of damage to the nitrile and carbonyl groups occurred during irradiation at either 286.80 or 288.45 eV. This is attributed to damage transfer between the C=N and C=O groups mediated by primary electrons, secondary electrons or radical/ionic processes, aided by their close spatial proximity. Although the overall thickness of the bilayer sample at 70 nm is smaller than the lateral line spreading of 100 nm, the interface between the layers appears to effectively block the transport of energy, and hence damage, between the two layers. The origins of the line spreading in homogeneous phases and possible origins of the damage blocking effect of the interface are discussed. To demonstrate chemically selective patterning, high-resolution multi-wavelength patterns were created in the PMMA/PAN bilayer system.

  18. The structure of the coronal soft X-ray source associated with the dark filament disappearance of 1991 September 28 using the Yohkoh Soft X-ray Telescope

    NASA Technical Reports Server (NTRS)

    Mcallister, Alan; Uchida, Yutaka; Tsuneta, Saku; Strong, Keith T.; Acton, Loren W.; Hiei, Eijiro; Bruner, Marilyn E.; Watanabe, Takashi; Shibata, Kazunari

    1992-01-01

    The structure of the coronal soft X-ray source associated with the dark filament disappearance on September 28, 1991, observed with the Soft X-ray Telescope, is examined as a possible example of the 'eruption-reconnection' model of filament disappearance. The results suggest, however, that this model may not fit. There is a strong possibility that much of the dark filament mass remains in the heated unwinding axial field.

  19. System for in situ studies of atmospheric corrosion of metal films using soft x-ray spectroscopy and quartz crystal microbalance.

    PubMed

    Forsberg, J; Duda, L-C; Olsson, A; Schmitt, T; Andersson, J; Nordgren, J; Hedberg, J; Leygraf, C; Aastrup, T; Wallinder, D; Guo, J-H

    2007-08-01

    We present a versatile chamber ("atmospheric corrosion cell") for soft x-ray absorption/emission spectroscopy of metal surfaces in a corrosive atmosphere allowing novel in situ electronic structure studies. Synchrotron x rays passing through a thin window separating the corrosion cell interior from a beamline vacuum chamber probe a metal film deposited on a quartz crystal microbalance (QCM) or on the inside of the window. We present some initial results on chloride induced corrosion of iron surfaces in humidified synthetic air. By simultaneous recording of QCM signal and soft x-ray emission from the corroding sample, correlation between mass changes and variations in spectral features is facilitated.

  20. Toward the development of a soft x-ray reflection imaging microscope in the Schwarzschild configuration using a soft x-ray laser at 18. 2 nm

    SciTech Connect

    Dicicco, D.; Rosser, R. ); Kim, D.; Suckewer, S. . Plasma Physics Lab.)

    1991-12-01

    We present the recent results obtained from a soft X-ray reflection imaging microscope in the Schwarzschild configuration. The microscope demonstrated a spatial resolution of 0.7 {mu}m with a magnification of 16 at 18.2 nm. The soft X-ray laser at 18.2 nm was used as an X-ray source. Mo/Si multilayers were coated on the Schwarzschild optics and the normal incidence reflectivity at 18.2 nm per surface was measured to be {approximately} 20 %. 18 refs., 6 figs.

  1. Correlative Analysis of Hard and Soft X-ray Emissions in Solar Flares

    NASA Technical Reports Server (NTRS)

    Zarro, Dominic M.

    1997-01-01

    This report describes research performed under the Phase 3 Compton Gamma-Ray Observatory (CGRO) Guest Investigator Program. The objective of this work is to study different mechanisms of solar flare heating by comparing their predictions with simultaneous hard and soft X-ray observations. The datasets used in this work consist of hard X-ray observations from the CGRO Burst and Transient Source Experiment (BATSE) and soft X-ray observations from the Bragg Crystal Spectrometer (BCS) and Soft X-ray telescope (SXT) on the Japanese Yohkoh spacecraft.

  2. X-ray/UV variability and the origin of soft X-ray excess emission from II Zw 177

    NASA Astrophysics Data System (ADS)

    Pal, Main; Dewangan, Gulab C.; Misra, Ranjeev; Pawar, Pramod K.

    2016-03-01

    We study X-ray and UV emission from the narrow-line Seyfert 1 galaxy II Zw 177 using a 137 ks long and another 13 ks short XMM-Newton observation performed in 2012 and 2001, respectively. Both observations show soft X-ray excess emission contributing 76.9 ± 4.9 per cent in 2012 and 58.8 ± 10.2 per cent in 2001 in the 0.3-2 keV band. We find that both blurred reflection from an ionized disc and Comptonized disc emission describe the observed soft excess well. Time-resolved spectroscopy on scales of ˜20 ks reveals strong correlation between the soft excess and the power-law components. The fractional variability amplitude Fvar derived from EPIC-pn light curves at different energy bands is nearly constant (Fvar ˜ 20 per cent). This is in contrast to other active galactic nuclei where the lack of short term variation in soft X-ray excess emission has been attributed to intense light bending in the framework of the `lamppost' model. Thus, the variations in power-law emission are most likely intrinsic to corona rather than just due to the changes of height of compact corona. The variable UV emission (Fvar ˜ 1 per cent) is uncorrelated to any of the X-ray components on short time-scales suggesting that the UV emission is not dominated by the reprocessed emission. The gradual observed decline in the UV emission in 2012 may be related to the secular decline due to the changes in the accretion rate. In this case, the short term X-ray variability is not due to the changes in the seed photons but intrinsic to the hot corona.

  3. Gadolinium Deposition in Nephrogenic Systemic Fibrosis: An Examination of Tissue using Synchrotron X-ray Fluorescence Spectroscopy

    SciTech Connect

    High, W.; Ranville, J; Brown, M; Punshon, T; Lanzirotti, A; Jackson, B

    2010-01-01

    Nephrogenic systemic fibrosis is a fibrosing disorder associated with gadolinium (Gd)-based contrast agents dosed during renal insufficiency. In two patients, Gd deposition in tissue affected by nephrogenic systemic fibrosis was quantified using inductively coupled plasma mass spectrometry. The presence of Gd was confirmed and mapped using synchrotron x-ray fluorescence spectroscopy. Affected skin and soft tissue from the lower extremity demonstrated 89 and 209 ppm ({micro}g/g, dry weight, formalin fixed) in cases 1 and 2, respectively. In case 2, the same skin and soft tissue was retested after paraffin embedding, with the fat content removed by xylene washes, and this resulted in a measured value of 189 ppm ({micro}g/g, dry weight, paraffin embedded). Synchrotron x-ray fluorescence spectroscopy confirmed Gd in the affected tissue of both cases, and provided high-sensitivity and high-resolution spatial mapping of Gd deposition. A gradient of Gd deposition in tissue correlated with fibrosis and cellularity. Gd deposited in periadnexal locations within the skin, including hair and eccrine ducts, where it colocalized to areas of high calcium and zinc content. Because of the difficulty in obtaining synchrotron x-ray fluorescence spectroscopy scans, tissue from only two patients were mapped. A single control with kidney disease and gadolinium-based contrast agent exposure did not contain Gd. Gd content on a gravimetric basis was impacted by processing that removed fat and altered the dry weight of the specimens. Gradients of Gd deposition in tissue corresponded to fibrosis and cellularity. Adnexal deposition of Gd correlated with areas of high calcium and zinc content.

  4. Multilayer on-chip stacked Fresnel zone plates: Hard x-ray fabrication and soft x-ray simulations

    SciTech Connect

    Li, Kenan; Wojcik, Michael J.; Ocola, Leonidas E.; Divan, Ralu; Jacobsen, Chris

    2015-11-01

    Fresnel zone plates are widely used as x-ray nanofocusing optics. To achieve high spatial resolution combined with good focusing efficiency, high aspect ratio nanolithography is required, and one way to achieve that is through multiple e-beam lithography writing steps to achieve on-chip stacking. A two-step writing process producing 50 nm finest zone width at a zone thickness of 1.14 µm for possible hard x-ray applications is shown here. The authors also consider in simulations the case of soft x-ray focusing where the zone thickness might exceed the depth of focus. In this case, the authors compare on-chip stacking with, and without, adjustment of zone positions and show that the offset zones lead to improved focusing efficiency. The simulations were carried out using a multislice propagation method employing Hankel transforms.

  5. Recover soft x-ray spectrum using virtual flat response channels with filtered x-ray diode array

    SciTech Connect

    Song Tianming; Yang Jiamin; Yi Rongqing

    2012-11-15

    A method for the recovery of soft x-ray spectra in indirect-drive inertial confinement fusion experiments is presented. Virtual detection channels with bandpass responses are obtained using linear combinations of the channel response functions of a filtered x-ray diode array and a weighted correction is introduced to improve the recovery. These virtual channels can be used to calculate radiation fluxes in some specific photon energy bands and hence to recover the spectrum of the whole photon energy range from 80 eV to 4.5 keV. Examples are listed which demonstrate the capability of this method to unfold various spectra such as Planck spectra with different radiation temperatures and to obtain x-ray flux of certain narrow energy interval.

  6. Exotic X-ray back-diffraction: a path toward a soft inelastic X-ray scattering spectrometer

    SciTech Connect

    Honnicke, Marcelo Goncalves; Conley, Raymond; Cusatis, Cesar; Kakuno, Edson Massayuki; Zhou, Juan; Bouet, Nathalie; Marques, Joao Basso; Vicentin, Flavio Cesar

    2014-10-01

    In this work, soft X-ray back-diffraction (XBD; X-ray diffraction at angles near and exactly equal to 90 degrees) is explored. The experiment was conducted at the SXS beamline at Laboratorio Nacional de Luz Sincrotron, Brazil, at similar to 3.2 keV. A high-resolution Si(220) multi-bounce back-diffraction monochromator was designed and constructed for this experiment. An ultra-thin Si(220) crystal (5 mu m thick) was used as the sample. This ultra-thin crystal was characterized by profilometry, rocking-curve measurements and X-ray topography prior to the XBD measurements. It is shown that the measured forward-diffracted beam (o-beam) profiles, taken at different temperatures, are in close agreement with profiles predicted by the extended dynamical theory of X-ray diffraction, with the absence of multiple-beam diffraction (MBD). This is an important result for future studies on the basic properties of back-diffracted X-ray beams at energies slightly above the exact XBD condition (extreme condition where XBD is almost extinguished). Also, the results presented here indicate that stressed crystals behave like ideal strain-free crystals when used for low-energy XBD. This is mainly due to the large widths of XBD profiles, which lead to a low strain sensitivity in the detection of defects. This result opens up new possibilities for mounting spherical analyzers without degrading the energy resolution, at least for low energies. This is a path that may be used to construct a soft inelastic X-ray scattering spectrometer where different applications such as element-specific magnetic imaging tools could be explored. (C) 2014 International Union of Crystallography

  7. Synchrotron x-ray imaging of acoustic cavitation bubbles induced by acoustic excitation

    NASA Astrophysics Data System (ADS)

    Jung, Sung Yong; Park, Han Wook; Park, Sung Ho; Lee, Sang Joon

    2017-04-01

    The cavitation induced by acoustic excitation has been widely applied in various biomedical applications because cavitation bubbles can enhance the exchanges of mass and energy. In order to minimize the hazardous effects of the induced cavitation, it is essential to understand the spatial distribution of cavitation bubbles. The spatial distribution of cavitation bubbles visualized by the synchrotron x-ray imaging technique is compared to that obtained with a conventional x-ray tube. Cavitation bubbles with high density in the region close to the tip of the probe are visualized using the synchrotron x-ray imaging technique, however, the spatial distribution of cavitation bubbles in the whole ultrasound field is not detected. In this study, the effects of the ultrasound power of acoustic excitation and working medium on the shape and density of the induced cavitation bubbles are examined. As a result, the synchrotron x-ray imaging technique is useful for visualizing spatial distributions of cavitation bubbles, and it could be used for optimizing the operation conditions of acoustic cavitation.

  8. Synchrotron-based Scattered Radiation from Phantom Materials used in X-ray CT

    SciTech Connect

    Rao, D.; Swapna, M; Cesareo, R; Brunetti, A; Akatsuka, T; Yuasa, T; Takeda, T; Gigante, G

    2010-01-01

    Synchrotron-based scattered radiation form low-contrast phantom materials prepared from polyethylene, polystyrene, nylon, and Plexiglas is used as test objects in X-ray CT was examined with 8, 10 and 12 keV X-rays. These phantom materials of medical interest will contains varying proportions of low atomic number elements. The assessment will allowed us to estimate the fluorescence to total scattered radiation. Detected the fluorescence spectra and the associated scattered radiation from calcium hydroxyapatite phantom with 8, 10 and 12 keV synchrotron X-rays. Samples with Bonefil (60% and 70% of calcium hydroxyapatite) and Bone cream (35-45% of calcium hydroxyapatite), were used. Utilized the X-ray micro-spectroscopy beamline facility, X27A, available at NSLS, BNL, USA. The primary beam with a spot size of the order of {approx}10 {micro}m, has been used for focusing. With this spatial resolution and high flux throuput, the synchrotron-based scattered radiation from the phantom materials were measured using a liquid-nitrogen-cooled 13-element energy-dispersive high-purity germanium detector.

  9. Microscopic x-ray imaging system for biomedical applications using synchrotron radiation

    NASA Astrophysics Data System (ADS)

    Umetani, Keiji; Kobatake, Makito; Yamamoto, Akira; Yamashita, Takenori; Imai, Shigeki

    2007-02-01

    An X-ray direct-conversion type detector with a spatial resolution of 10-11 μm was developed for real-time biomedical imaging. The detector incorporates the X-ray SATICON pickup tube with a photoconductive target layer of amorphous selenium. For high-resolution imaging, the X-ray image is directly converted into an electric signal in the photoconductive layer without image blur. Microangiography experiments were carried out for depicting angiogenic vessels in a rabbit model of cancer using the direct-conversion detector and a third generation synchrotron radiation source at SPring-8. In synchrotron radiation radiography, a long source-to-object distance and a small source spot can produce high-resolution images. After transplantation of cancer cells into the rabbit auricle, small tumor blood vessels with diameters of 20-30 μm in an immature vascular network produced by angiogenesis were visualized by contrast material injection into the auricular artery at a monochromatic X-ray energy of 33.2 keV just above the iodine K-edge energy. The synchrotron radiation system is a useful tool to evaluate the micro-angioarchitecture of malignant tumors in animal models of cancer for in vivo preclinical studies.

  10. Real space soft x-ray imaging at 10 nm spatial resolution

    SciTech Connect

    Chao, Weilun; Fischer, Peter; Tyliszczak, T.; Rekawa, Senajith; Anderson, Erik; Naulleau, Patrick

    2011-04-24

    Using Fresnel zone plates made with our robust nanofabrication processes, we have successfully achieved 10 nm spatial resolution with soft x-ray microscopy. The result, obtained with both a conventional full-field and scanning soft x-ray microscope, marks a significant step forward in extending the microscopy to truly nanoscale studies.

  11. Soft X-ray laser source development and applications experiments at Lawrence Livermore National Laboratory

    NASA Astrophysics Data System (ADS)

    Keane, C. J.; Ceglio, N. M.; MacGowan, B. J.; Matthews, D. L.; Nilson, D. G.

    1989-11-01

    Recent progress in experimental laboratory soft X-ray laser research at Lawrence Livermore National Laboratory (LLNL) is reviewed. Research at LLNL in this area has concentrated on further characterizing and understanding neon-like X-ray laser plasmas, investigating soft X-ray amplification at shorter wavelengths, and demonstrating examples of X-ray laser applications. For the standard 200-A neon-like selenium collisional excitation laser, the output source size as well as the beam time history, divergence, energy, and spatial profile have been measured. Gain has been demonstrated at wavelengths as short as 50.3 A in nickel-like ytterbium. Several recombination X-ray laser schemes have also been investigated. X-ray laser holography, cavity operation of an X-ray laser, and the capability to point and focus the output laser beam have been demonstrated.

  12. Soft x-ray transmission grating spectrometer for X-ray Surveyor and smaller missions with high resolving power

    NASA Astrophysics Data System (ADS)

    Heilmann, Ralf K.; Bruccoleri, Alexander; Schattenburg, Mark; Kolodziejczak, jeffery; Gaskin, Jessica; O'Dell, Stephen L.

    2017-01-01

    A number of high priority subjects in astrophysics are addressed by a state-of-the-art soft x-ray grating spectrometer, e.g. the role of Active Galactic Nuclei in galaxy and star formation, characterization of the WHIM and the “missing baryon” problem, characterization of halos around the Milky Way and nearby galaxies, and stellar coronae and surrounding winds and disks. An Explorer-scale, large-area (A > 1,000 cm2), high resolving power (R > 3,000) soft x-ray grating spectrometer is highly feasible based on Critical-Angle Transmission (CAT) grating technology, even for telescopes with angular resolution of 5-10 arcsec. Significantly higher performance could be provided by a CAT grating spectrometer on an X-ray-Surveyor-type mission (A > 4,000 cm2, R > 5,000). CAT gratings combine advantages of blazed reflection gratings (high efficiency, use of higher orders) with those of transmission gratings (low mass, relaxed alignment tolerances and temperature requirements, transparent at higher energies) with minimal mission resource requirements. Blazing is achieved through grazing-incidence reflection off the smooth silicon grating bar sidewalls. Silicon is well matched to the soft x-ray band, and 30% absolute diffraction efficiency has been acheived with clear paths for further improvement. CAT gratings with sidewalls made of high-Z elements allow extension of blazing to higher energies and larger dispersion angles, enabling higher resolving power at shorter wavelengths. X-ray data from CAT gratings coated with a thin layer of platinum using atomic layer deposition demonstrate efficient blazing to higher energies and much larger blaze angles than possible with silicon alone. Measurements of the resolving power of a breadboard CAT grating spectrometer consisting of a Wolter-I slumped-glass focusing optic from GSFC and CAT gratings, taken at the MSFC Stray Light Facility, have demonstrated resolving power > 10,000. Thus currently fabricated CAT gratings are compatible

  13. Synchrotron-based X-ray computed tomography during compression loading of cellular materials

    DOE PAGES

    Cordes, Nikolaus L.; Henderson, Kevin; Stannard, Tyler; ...

    2015-04-29

    Three-dimensional X-ray computed tomography (CT) of in situ dynamic processes provides internal snapshot images as a function of time. Tomograms are mathematically reconstructed from a series of radiographs taken in rapid succession as the specimen is rotated in small angular increments. In addition to spatial resolution, temporal resolution is important. Thus temporal resolution indicates how close together in time two distinct tomograms can be acquired. Tomograms taken in rapid succession allow detailed analyses of internal processes that cannot be obtained by other means. This article describes the state-of-the-art for such measurements acquired using synchrotron radiation as the X-ray source.

  14. Synchrotron-based X-ray computed tomography during compression loading of cellular materials

    SciTech Connect

    Cordes, Nikolaus L.; Henderson, Kevin; Stannard, Tyler; Williams, Jason J.; Xiao, Xianghui; Robinson, Mathew W. C.; Schaedler, Tobias A.; Chawla, Nikhilesh; Patterson, Brian M.

    2015-04-29

    Three-dimensional X-ray computed tomography (CT) of in situ dynamic processes provides internal snapshot images as a function of time. Tomograms are mathematically reconstructed from a series of radiographs taken in rapid succession as the specimen is rotated in small angular increments. In addition to spatial resolution, temporal resolution is important. Thus temporal resolution indicates how close together in time two distinct tomograms can be acquired. Tomograms taken in rapid succession allow detailed analyses of internal processes that cannot be obtained by other means. This article describes the state-of-the-art for such measurements acquired using synchrotron radiation as the X-ray source.

  15. Focusing synchrotron radiation using a polycapillary half-focusing X-ray lens for imaging.

    PubMed

    Sun, Tianxi; Zhang, Meiling; Liu, Zhiguo; Zhang, Zhiguang; Li, Gang; Ma, Yongzhong; Du, Xiaoguang; Jia, Quanjie; Chen, Yu; Yuan, Qingxi; Huang, Wanxia; Zhu, Peiping; Ding, Xunliang

    2009-01-01

    An imaging system based on a polycapillary half-focusing X-ray lens (PHFXRL) and synchrotron radiation source has been designed. The focal spot size and the gain in power density of the PHFXRL were 22 microm (FWHM) and 4648, respectively, at 14.0 keV. The spatial resolution of this new imaging system was better than 5 microm when an X-ray charge coupled device with a pixel size of 10.9 x 10.9 microm was used. A fossil of an ancient biological specimen was imaged using this system.

  16. Diamond anvil cell radial x-ray diffraction program at the National Synchrotron Light Source.

    PubMed

    Hu, J Z; Mao, H K; Shu, J F; Guo, Q Z; Liu, H Z

    2006-06-28

    During the past decade, the radial x-ray diffraction method using a diamond anvil cell (DAC) has been developed at the X17C beamline of the National Synchrotron Light Source. The detailed experimental procedure used with energy dispersive x-ray diffraction is described. The advantages and limitations of using the energy dispersive method for DAC radial diffraction studies are also discussed. The results for FeO at 135 GPa and other radial diffraction experiments performed at X17C are discussed in this report.

  17. Evaluation of sagittal focusing for a spherical quartz crystal x-ray analyzer with synchrotron radiation

    SciTech Connect

    Pereira, Nino R.; Macrander, Albert T.; Hill, Kenneth W.; Baronova, Elena O.; George, Kevin M.; Kotick, Jordan T.

    2015-10-01

    To attain optimum performance in applications such as x-ray imaging and spectroscopy, a spherically bent crystal must diffract well across its entire surface. X-ray topography of sample crystals shows isolated regions where diffraction is problematic, even for a crystal where inspection with visible light does not suggest problems. Covering problem spots may improve the crystal’s focus and decrease the background. We explore the special properties of synchrotron radiation to examine typical spherical crystals from alpha-quartz, in a perpendicular geometry that is especially convenient to examine sagittal focusing.

  18. Spatial resolution of synchrotron x-ray microtomography in high energy range: Effect of x-ray energy and sample-to-detector distance

    NASA Astrophysics Data System (ADS)

    Seo, D.; Tomizato, F.; Toda, H.; Uesugi, K.; Takeuchi, A.; Suzuki, Y.; Kobayashi, M.

    2012-12-01

    Spatial resolution of three-dimensional images obtained by synchrotron X-ray microtomography technique is evaluated using cyclic bar patterns machined on a steel wire. Influences of X-ray energy and the sample-to-detector distance on spatial resolution were investigated. High X-ray energies of 33-78 keV are applied due to the high X-ray absorption of transition metals. Best spatial resolution of about 1.2 μm pitch was observed at the sample-to-detector distance range of 20-110 mm and at the energy range of 68-78 keV. Several factors such as X-ray scattering and diffraction phenomena affecting the degradation of spatial resolution are also discussed.

  19. DNA nucleobase synthesis at Titan atmosphere analog by soft X-rays.

    PubMed

    Pilling, Sergio; Andrade, Diana P P; Neto, Alvaro C; Rittner, Roberto; Naves de Brito, Arnaldo

    2009-10-22

    Titan, the largest satellite of Saturn, has an atmosphere chiefly made up of N(2) and CH(4) and includes traces of many simple organic compounds. This atmosphere also partly consists of haze and aerosol particles which during the last 4.5 gigayears have been processed by electric discharges, ions, and ionizing photons, being slowly deposited over the Titan surface. In this work, we investigate the possible effects produced by soft X-rays (and secondary electrons) on Titan aerosol analogs in an attempt to simulate some prebiotic photochemistry. The experiments have been performed inside a high vacuum chamber coupled to the soft X-ray spectroscopy beamline at the Brazilian Synchrotron Light Source, Campinas, Brazil. In-situ sample analyses were performed by a Fourier transform infrared spectrometer. The infrared spectra have presented several organic molecules, including nitriles and aromatic CN compounds. After the irradiation, the brownish-orange organic residue (tholin) was analyzed ex-situ by gas chromatographic (GC/MS) and nuclear magnetic resonance ((1)H NMR) techniques, revealing the presence of adenine (C(5)H(5)N(5)), one of the constituents of the DNA molecule. This confirms previous results which showed that the organic chemistry on the Titan surface can be very complex and extremely rich in prebiotic compounds. Molecules like these on the early Earth have found a place to allow life (as we know) to flourish.

  20. Design and fabrication of an active polynomial grating for soft-X-ray monochromators and spectrometers

    NASA Astrophysics Data System (ADS)

    Chen, S.-J.; Chen, C. T.; Perng, S. Y.; Kuan, C. K.; Tseng, T. C.; Wang, D. J.

    2001-07-01

    An active polynomial grating has been designed for use in synchrotron radiation soft-X-ray monochromators and spectrometers. The grating can be dynamically adjusted to obtain the third-order-polynomial surface needed to eliminate the defocus and coma aberrations at any photon energy. Ray-tracing results confirm that a monochromator or spectrometer based on this active grating has nearly no aberration limit to the overall spectral resolution in the entire soft-X-ray region. The grating substrate is made of a precisely milled 17-4 PH stainless steel parallel plate, which is joined to a flexure-hinge bender shaped by wire electrical discharge machining. The substrate is grounded into a concave cylindrical shape with a nominal radius and then polished to achieve a roughness of 0.45 nm and a slope error of 1.2 μrad rms. The long trace profiler measurements show that the active grating can reach the desired third-order polynomial with a high degree of figure accuracy.

  1. The first microbeam synchrotron X-ray fluorescence beamline at the Siam Photon Laboratory.

    PubMed

    Tancharakorn, Somchai; Tanthanuch, Waraporn; Kamonsutthipaijit, Nuntaporn; Wongprachanukul, Narupon; Sophon, Methee; Chaichuay, Sarunyu; Uthaisar, Chunmanus; Yimnirun, Rattikorn

    2012-07-01

    The first microbeam synchrotron X-ray fluorescence (µ-SXRF) beamline using continuous synchrotron radiation from Siam Photon Source has been constructed and commissioned as of August 2011. Utilizing an X-ray capillary half-lens allows synchrotron radiation from a 1.4 T bending magnet of the 1.2 GeV electron storage ring to be focused from a few millimeters-sized beam to a micrometer-sized beam. This beamline was originally designed for deep X-ray lithography (DXL) and was one of the first two operational beamlines at this facility. A modification has been carried out to the beamline in order to additionally enable µ-SXRF and synchrotron X-ray powder diffraction (SXPD). Modifications included the installation of a new chamber housing a Si(111) crystal to extract 8 keV synchrotron radiation from the white X-ray beam (for SXPD), a fixed aperture and three gate valves. Two end-stations incorporating optics and detectors for µ-SXRF and SXPD have then been installed immediately upstream of the DXL station, with the three techniques sharing available beam time. The µ-SXRF station utilizes a polycapillary half-lens for X-ray focusing. This optic focuses X-ray white beam from 5 mm × 2 mm (H × V) at the entrance of the lens down to a diameter of 100 µm FWHM measured at a sample position 22 mm (lens focal point) downstream of the lens exit. The end-station also incorporates an XYZ motorized sample holder with 25 mm travel per axis, a 5× ZEISS microscope objective with 5 mm × 5 mm field of view coupled to a CCD camera looking to the sample, and an AMPTEK single-element Si (PIN) solid-state detector for fluorescence detection. A graphic user interface data acquisition program using the LabVIEW platform has also been developed in-house to generate a series of single-column data which are compatible with available XRF data-processing software. Finally, to test the performance of the µ-SXRF beamline, an elemental surface profile has been obtained for

  2. Soft X Ray Telescope (SXT) focus error analysis

    NASA Technical Reports Server (NTRS)

    Ahmad, Anees

    1991-01-01

    The analysis performed on the soft x-ray telescope (SXT) to determine the correct thickness of the spacer to position the CCD camera at the best focus of the telescope and to determine the maximum uncertainty in this focus position due to a number of metrology and experimental errors, and thermal, and humidity effects is presented. This type of analysis has been performed by the SXT prime contractor, Lockheed Palo Alto Research Lab (LPARL). The SXT project office at MSFC formed an independent team of experts to review the LPARL work, and verify the analysis performed by them. Based on the recommendation of this team, the project office will make a decision if an end to end focus test is required for the SXT prior to launch. The metrology and experimental data, and the spreadsheets provided by LPARL are used at the basis of the analysis presented. The data entries in these spreadsheets have been verified as far as feasible, and the format of the spreadsheets has been improved to make these easier to understand. The results obtained from this analysis are very close to the results obtained by LPARL. However, due to the lack of organized documentation the analysis uncovered a few areas of possibly erroneous metrology data, which may affect the results obtained by this analytical approach.

  3. Cooling of neutron stars in soft x-ray transients

    NASA Astrophysics Data System (ADS)

    Han, Sophia; Steiner, Andrew W.

    2017-09-01

    Thermal states of neutron stars in soft x-ray transients (SXRTs) are thought to be determined by "deep crustal heating" in the accreted matter that drives the quiescent luminosity and cooling via emission of photons and neutrinos from the interior. In this study, we assume a global thermal steady state of the transient system and calculate the heating curves (quiescent surface luminosity as a function of mean accretion rate) predicted from theoretical models, taking into account variations in the equations of state, superfluidity gaps, thickness of the light element layer, and a phenomenological description of the direct Urca threshold. We further provide a statistical analysis on the uncertainties in these parameters, and compare the overall results with observations of several SXRTs, in particular the two sources containing the coldest (SAX J1808.4-3658) and the hottest (Aql X-1) neutron stars. Interpretation of the observational data indicates that the direct Urca process is required for the most massive stars and also suggests small superfluid gaps.

  4. Soft x-ray laser ablation of metals and dielectrics

    NASA Astrophysics Data System (ADS)

    Faenov, A.; Pikuz, T.; Ishino, M.; Inogamov, N.; Zhakhovsky, V.; Skobelev, I.; Hasegawa, N.; Nishikino, M.; Kando, M.; Kodama, R.; Kawachi, T.

    2017-05-01

    We present an overview of our systematic studies of the surface modifications resulting from the interactions of both single and multiple picosecond soft x-ray laser (SXRL) pulses with materials, such as gold (Au), copper (Cu), aluminum (Al), and lithium fluoride (LiF). We show experimentally the possibility of the precise nanometer size structures ( 10-40 nm) formation on their surfaces by ultra-low ( 10-30 mJ/cm2 ) fluencies of single picosecond SXRL pulse. Comparison experimental results with the atomistic model of ablation, which was developed for the single SXRL shot interaction with dielectrics and metals, is provided. Theoretical description of surface nanostructures is considered and is shown that such structures are formed after laser illumination in a process of mechanical spallation of ultrathin surface layer of molten metal. Spallation is accompanied by a strong foaming of melt, breaking of foam, and freezing of foam remnants. Those remnants form chaotic nanostructures, which are observed in experiments. Our measurements show that electron temperature of matter under irradiation of SXRL was lower than 1 eV. The model calculation also predicts that the ablation induced by the SXRL can create the significant low electron temperature. Our results demonstrate that tensile stress created in LiF and metals by short SXRL pulse can produce spallative ablation of target even for drastically small fluencies, which open new opportunities for material nano processing.

  5. White dwarfs as the maximal soft x-ray scatterers

    SciTech Connect

    Akbari-Moghanjoughi, M.

    2013-09-15

    In this paper, we explore the effect of density on the structure formation and the electromagnetic wave (EMw) elastic scattering on quantum plasmas, using the generalized quantum hydrodynamic model valid for a wide range of the plasma density and relativistic degeneracy. It is found that the electron quantum diffraction effect caused by the Bohm potential has a fundamental effect on the ion correlations in a degenerate electron fluid and crystallization in quantum plasmas in the solid-density regime and beyond. The ion correlations and structure formation are shown to be fundamentally affected by the plasma density and the relativistic degeneracy parameters. Moreover, distinct behavior is shown to exist between the non-relativistic and relativistic matter density regimes, regarding the normalized EMw elastic scattering cross-sections. It is theoretically discovered that the maximal Thomson scattering coincides with the average density of a typical white dwarf corresponding to the soft X-ray wavelength regime. Current research can be very useful in plasma optical diagnostic methods for a wide range of electron number-density from warm dense matter and inertial confinement fusion to the astrophysical compact objects.

  6. Implications of stimulated resonant X-ray scattering for spectroscopy, imaging, and diffraction in the regime from soft to hard X-rays

    NASA Astrophysics Data System (ADS)

    Schreck, Simon; Beye, Martin; Föhlisch, Alexander

    2015-12-01

    The ultrahigh peak brilliance available at X-ray free-electron lasers opens the possibility to transfer nonlinear spectroscopic techniques from the optical and infrared into the X-ray regime. Here, we present a conceptual treatment of nonlinear X-ray processes with an emphasis on stimulated resonant X-ray scattering as well as a quantitative estimate for the scaling of stimulated X-ray scattering cross sections. These considerations provide the order of magnitude for the required X-ray intensities to experimentally observe stimulated resonant X-ray scattering for photon energies ranging from the extreme ultraviolet to the soft and hard X-ray regimes. At the same time, the regime where stimulated processes can safely be ignored is identified. With this basis, we discuss prospects and implications for spectroscopy, scattering, and imaging experiments at X-ray free-electron lasers.

  7. Ground-based x-ray calibration of the Astro-H soft x-ray telescopes

    NASA Astrophysics Data System (ADS)

    Iizuka, Ryo; Hayashi, Takayuki; Maeda, Yoshitomo; Ishida, Manabu; Tomikawa, Kazuki; Sato, Toshiki; Kikuchi, Naomichi; Okajima, Takashi; Soong, Yang; Serlemitsos, Peter J.; Mori, Hideyuki; Izumiya, Takanori; Minami, Sari

    2014-07-01

    The X-ray astronomy satellite Astro-H, planned to be launched in 2015, will have several instruments for covering a wide energy band from a few hundreds eV to 600 keV. There are four X-ray telescopes, and two of them are soft X-ray telescopes (SXTs) covering up to about 15 keV. One is for an X-ray micro-calorimeter detector (SXS) and the other is for an X-ray CCD detector (SXI). The design of the SXTs is a conical approximation of the Wolter Type-I optics, which is also adopted for the telescopes on the previous mission Suzaku launched in 2005. It consists 203 thin-foil reflectors coated with gold monolayer (2000 Å) on the aluminum substrate (101.6 mm length) with the thickness of 0.15, 0.23 and 0.31 mm. These are nested confocally within the radius of 58 to 225 mm. The focal length of SXTs is 5.6 m. The weight is as light as ~ 43 kg per telescope. We present the current status of the calibration activity of two SXTs (SXT-1 and SXT-2). The developments of two SXTs were completed by NASA's Goddard Space Flight Center (GSFC). First X-ray measurements with a diverging beam at the GSFC 100m beamline found an angular resolution at 8.0 keV to be 1.1 and 1.0 arcmin (HPD) for SXT-1 and SXT-2, respectively. The full characterization of the X-ray performance has been now continuously calibrated with the 30m X-ray beamline facility at the Institute of Space and Astronautical Science (ISAS) of Japan Aerospace eXploration Agency (JAXA) in Japan. We adopted a raster scan method with a narrow X-ray pencil beam with the divergence of ~ 15". X-ray characterization of the two SXTs has been measured from May and December 2013, respectively. In the case of SXT-1, the on-axis effective area was approximately 580, 445, 370, 270, 185 and 90 cm2 at energies of 1.5, 4.5, 8.0, 9.4, 11.1 and 12.9 keV respectively. The effective area of SXT-2 is 2% larger than that of SXT-1 irrespective to X-ray energy. The on-axis angular resolution of SXT-1 was evaluated as 1.3 - 1.5 arcmin (HPD) in the 1

  8. TOPICAL REVIEW: Human soft tissue analysis using x-ray or gamma-ray techniques

    NASA Astrophysics Data System (ADS)

    Theodorakou, C.; Farquharson, M. J.

    2008-06-01

    This topical review is intended to describe the x-ray techniques used for human soft tissue analysis. X-ray techniques have been applied to human soft tissue characterization and interesting results have been presented over the last few decades. The motivation behind such studies is to provide improved patient outcome by using the data obtained to better understand a disease process and improve diagnosis. An overview of theoretical background as well as a complete set of references is presented. For each study, a brief summary of the methodology and results is given. The x-ray techniques include x-ray diffraction, x-ray fluorescence, Compton scattering, Compton to coherent scattering ratio and attenuation measurements. The soft tissues that have been classified using x-rays or gamma rays include brain, breast, colon, fat, kidney, liver, lung, muscle, prostate, skin, thyroid and uterus.

  9. Observation of soft X-rays from extended sources. [such as Perseus star cluster

    NASA Technical Reports Server (NTRS)

    Catura, R. C.; Acton, L. W.

    1974-01-01

    Efforts were directed toward surveying several supernova remnants for the emission of soft X-rays. Rather than attempt to detect such faint X-ray emission, the program was redirected to observe the spectrum and angular structure of the extended X-ray source in the Perseus cluster of galaxies and the super-nova remnant Puppis A. An attempt was made to detect X-ray line emission from Puppis A with a Bragg crystal spectrometer. Observations provide evidence for the presence of X-ray line emission in the spectrum of Puppis A near .65 keV.

  10. Antioxidant protects blood-testis barrier against synchrotron radiation X-ray-induced disruption

    PubMed Central

    Zhang, Tingting; Liu, Tengyuan; Shao, Jiaxiang; Sheng, Caibin; Hong, Yunyi; Ying, Weihai; Xia, Weiliang

    2015-01-01

    Synchrotron radiation (SR) X-ray has wide biomedical applications including high resolution imaging and brain tumor therapy due to its special properties of high coherence, monochromaticity and high intensity. However, its interaction with biological tissues remains poorly understood. In this study, we used the rat testis as a model to investigate how SR X-ray would induce tissue responses, especially the blood-testis barrier (BTB) because BTB dynamics are critical for spermatogenesis. We irradiated the male gonad with increasing doses of SR X-ray and obtained the testicles 1, 10 and 20 d after the exposures. The testicle weight and seminiferous tubule diameter reduced in a dose- and time-dependent manner. Cryosections of testes were stained with tight junction (TJ) component proteins such as occludin, claudin-11, JAM-A and ZO-1. Morphologically, increasing doses of SR X-ray consistently induced developing germ cell sloughing from the seminiferous tubules, accompanied by shrinkage of the tubules. Interestingly, TJ constituent proteins appeared to be induced by the increasing doses of SR X-ray. Up to 20 d after SR X-ray irradiation, there also appeared to be time-dependent changes on the steady-state level of these protein exhibiting differential patterns at 20-day after exposure, with JAM-A/claudin-11 still being up-regulated whereas occludin/ZO-1 being down-regulated. More importantly, the BTB damage induced by 40 Gy of SR X-ray could be significantly attenuated by antioxidant N-Acetyl-L-Cysteine (NAC) at a dose of 125 mg/kg. Taken together, our studies characterized the changes of TJ component proteins after SR X-ray irradiation, illustrating the possible protective effects of antioxidant NAC to BTB integrity. PMID:26413412

  11. X-ray grating interferometer for imaging at a second-generation synchrotron radiation source

    NASA Astrophysics Data System (ADS)

    Herzen, Julia; Beckmann, Felix; Donath, Tilman; Ogurreck, Malte; David, Christian; Pfeiffer, Franz; Mohr, Jürgen; Reznikova, Elena; Riekehr, Stefan; Haibel, Astrid; Schulz, Georg; Müller, Bert; Schreyer, Andreas

    2010-09-01

    X-ray phase-contrast radiography and tomography enables to increase contrast for weakly absorbing materials. Recently, x-ray grating interferometers were developed which extend the possibility of phase-contrast imaging from highly brilliant radiation sources like third-generation synchrotron even to non-coherent sources. Here, we present a setup of an x-ray grating interferometer designed and installed at low-coherence wiggler source at the GKSS beamline W2 (HARWI II) operated at the second-generation synchrotron storage ring DORIS at the Deutsches Elektronen-Synchrotron (DESY, Hamburg, Germany). The beamline is dedicated to imaging in materials science. Equipped with the grating interferometer, it is the first synchrotron radiation beamline with a three-grating setup combining the advantages of phase-contrast imaging with monochromatic radiation with very high flux and a sufficiently large field of view for centimeter sized objects. Examples of radiography on laser-welded aluminum and magnesium joints are presented to demonstrate the high potential of the new gratingbased setup in the field of materials science. In addition, the results of an off-axis phase-contrast tomography of a human urethra with 15 mm in diameter are presented showing internal structures, which cannot be resolved by the conventional tomography in absorption mode.

  12. Towards hybrid pixel detectors for energy-dispersive or soft X-ray photon science.

    PubMed

    Jungmann-Smith, J H; Bergamaschi, A; Brückner, M; Cartier, S; Dinapoli, R; Greiffenberg, D; Huthwelker, T; Maliakal, D; Mayilyan, D; Medjoubi, K; Mezza, D; Mozzanica, A; Ramilli, M; Ruder, Ch; Schädler, L; Schmitt, B; Shi, X; Tinti, G

    2016-03-01

    JUNGFRAU (adJUstiNg Gain detector FoR the Aramis User station) is a two-dimensional hybrid pixel detector for photon science applications at free-electron lasers and synchrotron light sources. The JUNGFRAU 0.4 prototype presented here is specifically geared towards low-noise performance and hence soft X-ray detection. The design, geometry and readout architecture of JUNGFRAU 0.4 correspond to those of other JUNGFRAU pixel detectors, which are charge-integrating detectors with 75 µm × 75 µm pixels. Main characteristics of JUNGFRAU 0.4 are its fixed gain and r.m.s. noise of as low as 27 e(-) electronic noise charge (<100 eV) with no active cooling. The 48 × 48 pixels JUNGFRAU 0.4 prototype can be combined with a charge-sharing suppression mask directly placed on the sensor, which keeps photons from hitting the charge-sharing regions of the pixels. The mask consists of a 150 µm tungsten sheet, in which 28 µm-diameter holes are laser-drilled. The mask is aligned with the pixels. The noise and gain characterization, and single-photon detection as low as 1.2 keV are shown. The performance of JUNGFRAU 0.4 without the mask and also in the charge-sharing suppression configuration (with the mask, with a `software mask' or a `cluster finding' algorithm) is tested, compared and evaluated, in particular with respect to the removal of the charge-sharing contribution in the spectra, the detection efficiency and the photon rate capability. Energy-dispersive and imaging experiments with fluorescence X-ray irradiation from an X-ray tube and a synchrotron light source are successfully demonstrated with an r.m.s. energy resolution of 20% (no mask) and 14% (with the mask) at 1.2 keV and of 5% at 13.3 keV. The performance evaluation of the JUNGFRAU 0.4 prototype suggests that this detection system could be the starting point for a future detector development effort for either applications in the soft X-ray energy regime or for an energy

  13. Towards hybrid pixel detectors for energy-dispersive or soft X-ray photon science

    PubMed Central

    Jungmann-Smith, J. H.; Bergamaschi, A.; Brückner, M.; Cartier, S.; Dinapoli, R.; Greiffenberg, D.; Huthwelker, T.; Maliakal, D.; Mayilyan, D.; Medjoubi, K.; Mezza, D.; Mozzanica, A.; Ramilli, M.; Ruder, Ch.; Schädler, L.; Schmitt, B.; Shi, X.; Tinti, G.

    2016-01-01

    JUNGFRAU (adJUstiNg Gain detector FoR the Aramis User station) is a two-dimensional hybrid pixel detector for photon science applications at free-electron lasers and synchrotron light sources. The JUNGFRAU 0.4 prototype presented here is specifically geared towards low-noise performance and hence soft X-ray detection. The design, geometry and readout architecture of JUNGFRAU 0.4 correspond to those of other JUNGFRAU pixel detectors, which are charge-integrating detectors with 75 µm × 75 µm pixels. Main characteristics of JUNGFRAU 0.4 are its fixed gain and r.m.s. noise of as low as 27 e− electronic noise charge (<100 eV) with no active cooling. The 48 × 48 pixels JUNGFRAU 0.4 prototype can be combined with a charge-sharing suppression mask directly placed on the sensor, which keeps photons from hitting the charge-sharing regions of the pixels. The mask consists of a 150 µm tungsten sheet, in which 28 µm-diameter holes are laser-drilled. The mask is aligned with the pixels. The noise and gain characterization, and single-photon detection as low as 1.2 keV are shown. The performance of JUNGFRAU 0.4 without the mask and also in the charge-sharing suppression configuration (with the mask, with a ‘software mask’ or a ‘cluster finding’ algorithm) is tested, compared and evaluated, in particular with respect to the removal of the charge-sharing contribution in the spectra, the detection efficiency and the photon rate capability. Energy-dispersive and imaging experiments with fluorescence X-ray irradiation from an X-ray tube and a synchrotron light source are successfully demonstrated with an r.m.s. energy resolution of 20% (no mask) and 14% (with the mask) at 1.2 keV and of 5% at 13.3 keV. The performance evaluation of the JUNGFRAU 0.4 prototype suggests that this detection system could be the starting point for a future detector development effort for either applications in the soft X-ray energy regime or for an energy

  14. Synchrotron X-ray Analytical Techniques for Studying Materials Electrochemistry in Rechargeable Batteries

    DOE PAGES

    Lin, Feng; Liu, Yijin; Yu, Xiqian; ...

    2017-08-30

    Rechargeable battery technologies have ignited major breakthroughs in contemporary society, including but not limited to revolutions in transportation, electronics, and grid energy storage. The remarkable development of rechargeable batteries is largely attributed to in-depth efforts to improve battery electrode and electrolyte materials. There are, however, still intimidating challenges of lower cost, longer cycle and calendar life, higher energy density, and better safety for large scale energy storage and vehicular applications. Further progress with rechargeable batteries may require new chemistries (lithium ion batteries and beyond) and better understanding of materials electrochemistry in the various battery technologies. In the past decade, advancementmore » of battery materials has been complemented by new analytical techniques that are capable of probing battery chemistries at various length and time scales. Synchrotron X-ray techniques stand out as one of the most effective methods that allows for nearly nondestructive probing of materials characteristics such as electronic and geometric structures with various depth sensitivities through spectroscopy, scattering, and imaging capabilities. This article begins with the discussion of various rechargeable batteries and associated important scientific questions in the field, followed by a review of synchrotron X-ray based analytical tools (scattering, spectroscopy and imaging) and their successful applications (ex situ, in situ, and in operando) in gaining fundamental insights into these scientific questions. Furthermore, electron microscopy and spectroscopy complement the detection length scales of synchrotron X-ray tools, and are also discussed towards the end. We highlight the importance of studying battery materials by combining analytical techniques with complementary length sensitivities, such as the combination of X-ray absorption spectroscopy and electron spectroscopy with spatial resolution

  15. Probing nucleobase photo protection with soft x-rays

    NASA Astrophysics Data System (ADS)

    Gühr, Markus

    2013-05-01

    We [1] present a new method for ultrafast spectroscopy of molecular photoexcited dynamics. The technique uses a pair of femtosecond pulses: a photoexcitation pulse initiating excited state dynamics followed by a soft x-ray (SXR) probe pulse that core ionizes certain atoms inside the molecule. We observe the Auger decay of the core hole as a function of delay between the photoexcitation and SXR pulses. The core hole decay is particularly sensitive to the local valence electrons near the core and shows new types of propensity rules, compared to dipole selection rules in SXR absorption or emission spectroscopy. We apply the delayed ultrafast x-ray Auger probing (DUXAP) method to the specific problem of nucleobase photoprotection to demonstrate its potential. The ultraviolet photoexcited ππ * states of nucleobases are prone to chemical reactions with neighboring bases. To avoid this, the single molecules funnel the ππ * population to lower lying electronic states on an ultrafast timescale under violation of the Born-Oppenheimer approximation. The new type of propensity rule, which is confirmed by Auger decay simulations, allows us to have increased sensitivity on the direct relaxation from the ππ * state to the vibrationally hot electronic ground state. For the nucleobase thymine, we measure a decay of the ππ * state and a subsequent filling of the vibrationally hot ground state in 300 fs. This work was supported by the AMOS program within the Chemical Sciences, Geosciences, and Biosciences Division of the Office of Basic Energy Sciences, Office of Science, U.S. Department of Energy.Portions of this research were carried out at the Linac Coherent Light Source (LCLS) at the SLAC National Accelerator Laboratory. LCLS is an Office of Science User Facility operated for the U.S. Department of Energy Office of Science by Stanford University. Other portions of this research were carried out at the Advanced Light Source, which is supported by the Director, Office of

  16. Soft X-ray spectral observations of quasars and high X-ray luminosity Seyfert galaxies

    NASA Technical Reports Server (NTRS)

    Petre, R.; Mushotzky, R. F.; Krolik, J. H.; Holt, S. S.

    1983-01-01

    Results of the analysis of 28 Einstein SSS observations of 15 high X-ray luminosity (L(x) 10 to the 435 power erg/s) quasars and Seyfert type 1 nuclei are presented. The 0.75-4.5 keV spectra are in general well fit by a simple model consisting of a power law plus absorption by cold gas. The averager spectral index alpha is 0.66 + or - .36, consistent with alpha for the spectrum of these objects above 2 keV. In all but one case, no evidence was found for intrinsic absorption, with an upper limit of 2 x 10 to the 21st power/sq cm. Neither was evidence found for partial covering of the active nucleus by dense, cold matter (N(H) 10 to the 22nd power/sq cm; the average upper limit on the partial covering fraction is 0.5. There is no obvious correlation between spectral index and 0175-4.5 keV X-ray luminosity (which ranges from 3 x 10 to the 43rd to 47th powers erg/s or with other source properties. The lack of intrinsic X-ray absorption allows us to place constraints on the density and temperature of the broad-line emission region, and narrow line emission region, and the intergalactic medium.

  17. Energy dispersive X-ray diffraction in the diamond anvil, high-pressure apparatus - Comparison of synchrotron and conventional X-ray sources

    NASA Technical Reports Server (NTRS)

    Spain, I. L.; Black, D. R.

    1985-01-01

    The use of both conventional fixed-anode X-ray sources and synchrotron radiation to carry out energy-dispersive X-ray diffraction experiments at high pressure in a diamond anvil cell, is discussed. The photon flux at the sample and at the detector for the two cases are compared and the results are presented in graphs. It is shown that synchrotron radiation experiments can be performed with nearly two orders of magnitude increase in data rate if superior detectors and detector electronics are available.

  18. Energy dispersive X-ray diffraction in the diamond anvil, high-pressure apparatus - Comparison of synchrotron and conventional X-ray sources

    NASA Technical Reports Server (NTRS)

    Spain, I. L.; Black, D. R.

    1985-01-01

    The use of both conventional fixed-anode X-ray sources and synchrotron radiation to carry out energy-dispersive X-ray diffraction experiments at high pressure in a diamond anvil cell, is discussed. The photon flux at the sample and at the detector for the two cases are compared and the results are presented in graphs. It is shown that synchrotron radiation experiments can be performed with nearly two orders of magnitude increase in data rate if superior detectors and detector electronics are available.

  19. Diamond monochromator for high heat flux synchrotron x-ray beams

    SciTech Connect

    Khounsary, A.M.; Smither, R.K.; Davey, S.; Purohit, A.

    1992-12-01

    Single crystal silicon has been the material of choice for x-ray monochromators for the past several decades. However, the need for suitable monochromators to handle the high heat load of the next generation synchrotron x-ray beams on the one hand and the rapid and on-going advances in synthetic diamond technology on the other make a compelling case for the consideration of a diamond mollochromator system. In this Paper, we consider various aspects, advantage and disadvantages, and promises and pitfalls of such a system and evaluate the comparative an monochromator subjected to the high heat load of the most powerful x-ray beam that will become available in the next few years. The results of experiments performed to evaluate the diffraction properties of a currently available synthetic single crystal diamond are also presented. Fabrication of diamond-based monochromator is within present technical means.

  20. Inclined-incidence quasi-Fresnel lens for prefocusing of synchrotron radiation x-ray beams

    SciTech Connect

    Kagoshima, Yasushi; Takano, Hidekazu; Takeda, Shingo

    2012-10-15

    An inclined-incidence quasi-Fresnel lens made of acrylic resin has been developed for prefocusing in synchrotron radiation x-ray beamlines. By inclining the lens, the grating aspect ratio is large enough for x-ray use. As it operates in transmission mode with negligible beam deflection and offset, little additional equipment is needed to introduce it into existing beamlines. It is fabricated by sheet-press forming, enabling inexpensive mass production. The prototype was able to focus a 730-{mu}m-wide beam to a width of 80 {mu}m with a photon flux density gain of 5.6 at an x-ray energy of 10 keV.

  1. Solar flare hard and soft x ray relationship determined from SMM HXRBS and BCS data

    NASA Technical Reports Server (NTRS)

    Toot, G. David

    1989-01-01

    The exact nature of the solar flare process is still somewhat a mystery. A key element to understanding flares if the relationship between the hard x rays emitted by the most energetic portions of the flare and the soft x rays from other areas and times. This relationship was studied by comparing hard x ray light curved from the Hard X-Ray Burst Spectrometer (HXRBS) with the soft x ray light curve and its derivation from the Bent Crystal Spectrometer (BCS) which is part of the X-Ray Polychrometer (XRP), these instruments being on the Solar Maximum Mission spacecraft (SMM). Data sample was taken from flares observed with the above instruments during 1980, the peak of the previous maximum of solar activity. Flares were chosen based on complete coverage of the event by several instruments. The HXRBS data covers the x ray spectrum from about 25 keV to about 440 keV in 15 spectral channels, while the BCS data used covers a region of the Spectrum around 3 angstroms including emission from the Ca XIX ion. Both sets of data were summed over their spectral ranges and plotted against time at a maximum time resolution of around 3 seconds. The most popular theory of flares holds that a beam of electrons produces the hard x rays by bremsstrahlung while the soft x rays are the thermal response to this energy deposition. The question is whether the rate of change of soft x ray emission might reflect the variability of the electron beam and hence the variability of the hard x rays. To address this, we took the time derivative of the soft x ray light curve and compared it to the hard flares, 12 of them showed very closed agreement between the soft x ray derivative and the hard x ray light curve. The other five did not show this behavior but were similar to each other in general soft x ray behavior. Efforts to determine basic differences between the two kinds of flares continue. In addition the behavior of soft x ray temperature of flares was examined.

  2. Soft-x-ray hollow fiber optics with inner metal coating

    SciTech Connect

    Matsuura, Yuji; Oyama, Tadaaki; Miyagi, Mitsunobu

    2005-10-10

    A glass capillary with an inner metal coating is proposed to be used as soft-x-ray fiber optics in medical applications. Based on the results of theoretical calculations, nickel was chosen as the coating material for x rays radiated from a conventional x-ray tube. A nickel-coated capillary was fabricated by electroless deposition, and focusing and collimating effects were observed from measurements of the transmission efficiency of soft x rays. The transmission of a nickel-coated capillary with an inner diameter of 0.53 mm and a length of 300 mm was 10%, which is approximately double that of an uncoated glass capillary.

  3. Picosecond soft-x-ray pulses from a high-intensity laser-plasma source.

    PubMed

    Pelletier, J F; Chaker, M; Kieffer, J C

    1996-07-15

    We report time-resolved spectroscopic analysis of laser-produced plasma x-ray sources. Plasmas produced by a 400-fs 1-TW tabletop laser are characterized with a transmission grating spectrometer coupled to a soft-x-ray streak camera. Soft-x-ray radiation in the 1-6-nm range with durations of 2-7 ps is observed for copper and tantalum plasmas. The effect of incident laser energy on the x-ray pulse duration is also investigated.

  4. Solar flare hard and soft x ray relationship determined from SMM HXRBS and BCS data

    NASA Technical Reports Server (NTRS)

    Toot, G. David

    1989-01-01

    The exact nature of the solar flare process is still somewhat a mystery. A key element to understanding flares if the relationship between the hard x rays emitted by the most energetic portions of the flare and the soft x rays from other areas and times. This relationship was studied by comparing hard x ray light curved from the Hard X-Ray Burst Spectrometer (HXRBS) with the soft x ray light curve and its derivation from the Bent Crystal Spectrometer (BCS) which is part of the X-Ray Polychrometer (XRP), these instruments being on the Solar Maximum Mission spacecraft (SMM). Data sample was taken from flares observed with the above instruments during 1980, the peak of the previous maximum of solar activity. Flares were chosen based on complete coverage of the event by several instruments. The HXRBS data covers the x ray spectrum from about 25 keV to about 440 keV in 15 spectral channels, while the BCS data used covers a region of the Spectrum around 3 angstroms including emission from the Ca XIX ion. Both sets of data were summed over their spectral ranges and plotted against time at a maximum time resolution of around 3 seconds. The most popular theory of flares holds that a beam of electrons produces the hard x rays by bremsstrahlung while the soft x rays are the thermal response to this energy deposition. The question is whether the rate of change of soft x ray emission might reflect the variability of the electron beam and hence the variability of the hard x rays. To address this, we took the time derivative of the soft x ray light curve and compared it to the hard flares, 12 of them showed very closed agreement between the soft x ray derivative and the hard x ray light curve. The other five did not show this behavior but were similar to each other in general soft x ray behavior. Efforts to determine basic differences between the two kinds of flares continue. In addition the behavior of soft x ray temperature of flares was examined.

  5. Synchronous scanning of undulator gap and monochromator for XAFS measurements in soft x-ray region.

    PubMed

    Tanaka, T; Matsubayashi, N; Imamura, M; Shimada, H

    2001-03-01

    Synchronous scanning of the undulator gap and a monochromator was done to obtain smooth profiles of incident x-rays that are suitable for XAFS measurements. By changing the gap from 150 mm(B=0.12 T) to 140 mm (B=0.15 T) with the use of the 3rd to 11th harmonic peaks, soft x-rays with energy from 200 eV to 1200 eV were obtained. The smooth profile of the incident x-rays provided high-quality measurement of XANES and EXAFS spectra in the soft x-ray region. Issues that would improve the synchronous scanning system are discussed.

  6. New Soft X-ray Beamline (BL10) at the SAGA Light Source

    SciTech Connect

    Yoshimura, D.; Setoyama, H.; Okajima, T.

    2010-06-23

    A new soft X-ray beamline (BL10) at the SAGA Light Source (SAGA-LS) was constructed at the end of 2008. Commissioning of this new beamline started at the beginning of 2009. Synchrotron radiation from a variably polarizing undulator (APPLE-II) can be used in this beamline. The obtained light is monochromatized by a varied-line-spacing plane grating monochromator with the variable included angle mechanism. Its designed resolving power and photon flux are 3,000-10,000 and 10{sup 12}-10{sup 9} photons/s at 300 mA, respectively. The performance test results were generally satisfactory. An overview of the optical design of the beamline and the current status of commissioning are reported.

  7. Soft x-ray coherent scattering: Instrument and methods at ESRF ID08

    SciTech Connect

    Beutier, Guillaume; Marty, Alain; Livet, Frederic; Laan, Gerrit van der; Stanescu, Stefan; Bencok, Peter

    2007-09-15

    An experimental setup has been developed to perform soft x-ray coherent scattering at beamline ID08 of the European Synchrotron Radiation Facility. An intense coherent beam was obtained by filtering the primary beam with the monochromator and a circular pinhole. A pinhole holder with motorized translations was installed inside the UHV chamber of the diffractometer. The scattered intensity was recorded in reflection geometry with a back-illuminated charge coupled device camera. As a demonstration we report experimental results of resonant magnetic scattering using coherent beam. The degree of coherence is evaluated, and it is shown that, while the vertical coherence is much higher than the horizontal one at the source, the situation is reversed at the diffractometer. The intensity of the coherent beam is also discussed.

  8. Laboratory soft-x-ray microscope for cryotomography of biological specimens.

    PubMed

    Bertilson, Michael; von Hofsten, Olov; Vogt, Ulrich; Holmberg, Anders; Christakou, Athanasia E; Hertz, Hans M

    2011-07-15

    Soft-x-ray cryotomography allows quantitative and high-resolution three-dimensional imaging of intact unstained cells. To date, the method relies on synchrotron-radiation sources, which limits accessibility for researchers. Here we present a laboratory water-window microscope for cryotomography. It is based on a λ=2.48 nm liquid-jet laser-plasma source, a normal-incidence multilayer condenser, a 30 nm zone-plate objective, and a cryotilt sample holder. We demonstrate high-resolution imaging, as well as quantitative tomographic imaging, of frozen intact cells. The reconstructed tomogram of the intracellular local absorption coefficient shows details down to ∼100 nm. © 2011 Optical Society of America

  9. Optical Design of VLS-PGM Soft X-Ray Beamline on Indus-2

    SciTech Connect

    Prasad, T. T.; Modi, M. H.; Lodha, G. S.

    2010-06-23

    The optical design of a soft x-ray beamline on the bending magnet of Indus-2 synchrotron source is presented. A Varied Line Spacing Plane Grating Monochromator (VLS-PGM) was adopted with Hettrick type optics. The VLS-PGM consists of a spherical mirror and three interchangeable gratings of line densities 1200 l/mm, 400 l/mm and 150 l/mm to efficiently cover the energy region 50-1500 eV. The VLS groove parameters were obtained by minimizing defocus aberration, coma and spherical aberration. The overall performance of the beamline was estimated by detailed raytracing calculations. The beamline design, results of the raytracing calculations and the expected performances are presented.

  10. High-precision soft x-ray polarimeter at Diamond Light Source.

    PubMed

    Wang, H; Dhesi, S S; Maccherozzi, F; Cavill, S; Shepherd, E; Yuan, F; Deshmukh, R; Scott, S; van der Laan, G; Sawhney, K J S

    2011-12-01

    The development and performance of a high-precision polarimeter for the polarization analysis in the soft x-ray region is presented. This versatile, high-vacuum compatible instrument is supported on a hexapod to simplify the alignment with a resolution less than 5 μrad, and can be moved with its own independent control system easily between different beamlines and synchrotron facilities. The polarimeter can also be used for the characterization of reflection and transmission properties of optical elements. A W/B(4)C multilayer phase retarder was used to characterize the polarization state up to 1200 eV. A fast and accurate alignment procedure was developed, and complete polarization analysis of the APPLE II undulator at 712 eV has been performed.

  11. High-precision soft x-ray polarimeter at Diamond Light Source

    NASA Astrophysics Data System (ADS)

    Wang, H.; Dhesi, S. S.; Maccherozzi, F.; Cavill, S.; Shepherd, E.; Yuan, F.; Deshmukh, R.; Scott, S.; van der Laan, G.; Sawhney, K. J. S.

    2011-12-01

    The development and performance of a high-precision polarimeter for the polarization analysis in the soft x-ray region is presented. This versatile, high-vacuum compatible instrument is supported on a hexapod to simplify the alignment with a resolution less than 5 μrad, and can be moved with its own independent control system easily between different beamlines and synchrotron facilities. The polarimeter can also be used for the characterization of reflection and transmission properties of optical elements. A W/B4C multilayer phase retarder was used to characterize the polarization state up to 1200 eV. A fast and accurate alignment procedure was developed, and complete polarization analysis of the APPLE II undulator at 712 eV has been performed.

  12. A SYNCHROTRON SELF-COMPTON-DISK REPROCESSING MODEL FOR OPTICAL/X-RAY CORRELATION IN BLACK HOLE X-RAY BINARIES

    SciTech Connect

    Veledina, Alexandra; Poutanen, Juri; Vurm, Indrek E-mail: juri.poutanen@oulu.fi

    2011-08-10

    The physical picture of the emission mechanisms operating in the X-ray binaries was put under question by the simultaneous optical/X-ray observations with high time resolution. The light curves of the two energy bands appeared to be connected and the cross-correlation functions observed in three black hole binaries exhibited a complicated shape. They show a dip of the optical emission a few seconds before the X-ray peak and the optical flare just after the X-ray peak. This behavior could not be explained in terms of standard optical emission candidates (e.g., emission from the cold accretion disk or a jet). We propose a novel model, which explains the broadband optical to the X-ray spectra and the variability properties. We suggest that the optical emission consists of two components: synchrotron radiation from the non-thermal electrons in the hot accretion flow and the emission produced by reprocessing of the X-rays in the outer part of the accretion disk. The first component is anti-correlated with the X-rays, while the second one is correlated, but delayed and smeared relative to the X-rays. The interplay of the components explains the complex shape of the cross-correlation function, the features in the optical power spectral density as well as the time lags.

  13. The prospects for soft x-ray contact microscopy using laser plasmas as an x-ray source

    SciTech Connect

    Stead, A.D.; Page, A.M.; Ford, T.W.

    1995-12-31

    Since its invention, a major concern of those using a microscope has been to improve the resolution without the introduction of artifacts. While light microscopy carries little risk of the introduction of artifacts, because the preparative techniques are often minimal, the resolution is somewhat limited. The advent of the electron microscope offered greatly improved resolution but since biological specimens require extensive preparation, the possibility of causing structural damage to the specimen is also increased. The ideal technique for structural studies of biological specimens would enable hydrated material to be examined without any preparation and with a resolution equal to that of electron microscopy. Soft x-ray microscopy certainly enables living material to be examined and whilst the resolution does not equal that of electron microscopy it exceeds that attainable by light microscopy. This paper briefly reviews the limitations of light and electron microscopy for the biologist and considers the various ways that soft x-rays might be used to image hydrated biological material. Consideration is given to the different sources that have been used for soft x-ray microscopy and the relative merits of laser-plasma sources are discussed.

  14. Controlled modulation of hard and soft X-ray induced tunneling currents utilizing coaxial metal-insulator-metal probe tips

    DOE PAGES

    Cummings, Marvin; Shirato, Nozomi; Kersell, Heath; ...

    2017-01-05

    Here, the effect of a local external electric field on the barrier potential of a tunneling gap is studied utilizing an emerging technique, synchrotron x-ray scanning tunneling microscopy. Here, we demonstrate that the shape of the potential barrier in the tunneling gap can be altered by a localized external electric field, generated by voltages placed on the metallic outer shield of a nanofabricated coaxial metal-insulator-metal tip, resulting in a controlled linear modulation of the tunneling current. Experiments at hard and soft x-ray synchrotron beamlines reveal that both the chemical contrast and magnetic contrast signals measured by the tip can bemore » drastically enhanced, resulting in improved local detection of chemistry and magnetization at the surface.« less

  15. X-Ray Optics for Science and Technology

    DTIC Science & Technology

    1993-12-22

    x - ray optics, x - ray lasers and synchrotron radiation. • NEW OPPORTUNITIES "AT SOFT - X - RAY WAVELENGTHS...possible to build the soft - x - ray equivalent of an early Lawrence Berkeley Laboratory and professor in residence in visible-light microscope. Materials...b: Soft - x - ray (24 A) image of a radial test pattern showing 300-A gold features. (Courtesy of Werner Meyer-Ilse, Lawrence Berkeley

  16. Soft X-ray probes of ultrafast dynamics for heterogeneous catalysis

    NASA Astrophysics Data System (ADS)

    Beye, M.; Föhlisch, A.

    2013-03-01

    Soft X-ray spectroscopy is one of the best tools to directly address the electronic structure, the driving force of chemical reactions. It enables selective studies on sample surfaces to single out reaction centers in heterogeneous catalytic reactions. With core-hole clock methods, specific dynamics are related to the femtosecond life time of a core-hole. Typically, this method is used with photoemission spectroscopy, but advancements in soft X-ray emission techniques render more specific studies possible. With the advent of bright femtosecond pulsed soft X-ray sources, highly selective pump-probe X-ray emission studies are enabled with temporal resolutions down to tens of femtoseconds. This finally allows to study dynamics in the electronic structure of adsorbed reaction centers on the whole range of relevant time scales - closing the gap between kinetic soft X-ray studies and the atto- to femtosecond core-hole clock techniques.

  17. National Synchrotron Light Source users manual: Guide to the VUV and x-ray beam lines

    SciTech Connect

    Gmuer, N.F.; White-DePace, S.M.

    1987-08-01

    The success of the National Synchrotron Light Source in the years to come will be based, in large part, on the size of the users community and the diversity of the scientific disciplines represented by these users. In order to promote this philosophy, this National Synchrotron Light Source (NSLS) Users Manual: Guide to the VUV and X-Ray Beam Lines, has been published. This manual serves a number of purposes. In an effort to attract new research, it will present to the scientific community-at-large the current and projected architecture and capabilities of the various VUV and x-ray beam lines and storage rings. We anticipate that this publication will be updated periodically in order to keep pace with the constant changes at the NSLS.

  18. Synchrotron X-Ray Reciprocal Space Mapping, Topography and Diffraction Resolution Studies of Macromolecular Crystal Quality

    NASA Technical Reports Server (NTRS)

    Boggon, T. J.; Helliwell, J. R.; Judge, Russell A.; Siddons, D. P.; Snell, Edward H.; Stojanoff, V.

    2000-01-01

    A comprehensive study of microgravity and ground grown chicken egg white lysozyme crystals is presented using synchrotron X-ray reciprocal space mapping, topography techniques and diffraction resolution. Microgravity crystals displayed, on average, reduced intrinsic mosaicities but no differences in terms of stress over their earth grown counterparts. Topographic analysis revealed that in the microgravity case the majority of the crystal was contributing to the peak of the reflection at the appropriate Bragg angle. In the earth case at the diffraction peak only a small volume of the crystal contributed to the intensity. The techniques prove to be highly complementary with the reciprocal space mapping providing a quantitative measure of the crystal mosaicity and stress (or variation in lattice spacing) and topography providing a qualitative overall assessment of the crystal in terms of its X-ray diffraction properties. Structural data collection was also carried out both at the synchrotron and in the laboratory.

  19. Thermal, structural, and fabrication aspects of diamond windows for high power synchrotron x-ray beamlines

    SciTech Connect

    Khounsary, A.M.; Phillips, W.

    1992-12-01

    Recent advances in chemical vapor deposition (CVD) technology have made it possible to produce thin free-standing diamond foils that can be used as the window material in high heat load, synchrotron beamlines. Numerical simulations suggest that these windows can offer an attractive and at times the only altemative to beryllium windows for use in third generation x-ray synchrotron radiation beamlines. Utilization, design, and fabrication aspects of diamond windows for high heat load x-ray beamlines are discussed, as are the microstructure characteristics bearing on diamond`s performance in this role. Analytic and numerical results are also presented to provide a basis for the design and testing of such windows.

  20. Extending synchrotron-based atomic physics experiments into the hard X-ray region

    SciTech Connect

    LeBrun, T.

    1996-12-31

    The high-brightness, hard x-ray beams available from third-generation synchrotron sources are opening new opportunities to study the deepest inner shells of atoms, an area where little work has been done and phenomena not observed in less tightly bound inner-shells are manifested. In addition scattering processes which are weak at lower energies become important, providing another tool to investigate atomic structure as well as an opportunity to study photon/atom interactions beyond photoabsorption. In this contribution the authors discuss some of the issues related to extending synchrotron-based atomic physics experiments into the hard x-ray region from the physical and the experimental point of view. They close with a discussion of a technique, resonant Raman scattering, that may prove invaluable in determining the spectra of the very highly-excited states resulting from the excitation of deep inner shells.

  1. Tracing X-rays through an L-shaped laterally graded multilayer mirror: a synchrotron application.

    PubMed

    Honnicke, Marcelo Goncalves; Huang, Xianrong; Keister, Jeffrey W; Kodituwakku, Chaminda Nalaka; Cai, Yong Q

    2010-05-01

    A theoretical model to trace X-rays through an L-shaped (nested or Montel Kirkpatrick-Baez mirrors) laterally graded multilayer mirror to be used in a synchrotron application is presented. The model includes source parameters (size and divergence), mirror figure (parabolic and elliptic), multilayer parameters (reflectivity, which depends on layer material, thickness and number of layers) and figure errors (slope error, roughness, layer thickness fluctuation Deltad/d and imperfection in the corners). The model was implemented through MATLAB/OCTAVE scripts, and was employed to study the performance of a multilayer mirror designed for the analyzer system of an ultrahigh-resolution inelastic X-ray scattering spectrometer at National Synchrotron Light Source II. The results are presented and discussed.

  2. Use of multielement detector systems with synchrotron x-ray sources

    SciTech Connect

    Thompson, A.C.

    1981-07-01

    The extremely high intensity and pulsed structure of synchrotron radiation x-ray sources put very demanding requirements on associated x-ray detectors. In current detector systems, trade-offs must be made between the efficiency, energy resolution, counting rate capability and the spatial resolution. Two detector systems are described which illustrate the optimization of these parameters for different applications of synchrotron radiation. One system is a segmented 16 channel multiwire proportional chamber which is used for fluorescent EXAFS measurements. The other is a 30 element Si(Li) linear detector array which is used for digital angiography experiments. The characteristics of these systems are discussed and recent results obtained with them are presented.

  3. Apparatus and Techniques for Time-resolved Synchrotron X-ray Diffraction using Diamond Anvil Cells

    NASA Astrophysics Data System (ADS)

    Smith, J.; Sinogeikin, S. V.; Lin, C.; Rod, E.; Bai, L.; Shen, G.

    2015-12-01

    Complementary advances in synchrotron sources, x-ray optics, area detectors, and sample environment control have recently made possible many time-resolved experimental techniques for studying materials at extreme pressure and temperature conditions. The High Pressure Collaborative Access Team (HPCAT) at the Advanced Photon Source has made a sustained effort to assemble a powerful collection of high-pressure apparatus for time-resolved research, and considerable time has been invested in developing techniques for collecting high-quality time-resolved x-ray scattering data. Herein we present key aspects of the synchrotron beamline and ancillary equipment, including source considerations, rapid (de)compression apparatus, high frequency imaging detectors, and software suitable for processing large volumes of data. A number of examples are presented, including fast equation of state measurements, compression rate dependent synthesis of metastable states in silicon and germanium, and ultrahigh compression rates using a piezoelectric driven diamond anvil cell.

  4. Synchrotron X-Ray Reciprocal Space Mapping, Topography and Diffraction Resolution Studies of Macromolecular Crystal Quality

    NASA Technical Reports Server (NTRS)

    Boggon, T. J.; Helliwell, J. R.; Judge, Russell A.; Siddons, D. P.; Snell, Edward H.; Stojanoff, V.

    2000-01-01

    A comprehensive study of microgravity and ground grown chicken egg white lysozyme crystals is presented using synchrotron X-ray reciprocal space mapping, topography techniques and diffraction resolution. Microgravity crystals displayed, on average, reduced intrinsic mosaicities but no differences in terms of stress over their earth grown counterparts. Topographic analysis revealed that in the microgravity case the majority of the crystal was contributing to the peak of the reflection at the appropriate Bragg angle. In the earth case at the diffraction peak only a small volume of the crystal contributed to the intensity. The techniques prove to be highly complementary with the reciprocal space mapping providing a quantitative measure of the crystal mosaicity and stress (or variation in lattice spacing) and topography providing a qualitative overall assessment of the crystal in terms of its X-ray diffraction properties. Structural data collection was also carried out both at the synchrotron and in the laboratory.

  5. Synchrotron X-ray diffraction characterization of healthy and fluorotic human dental enamel

    NASA Astrophysics Data System (ADS)

    Colaço, M. V.; Barroso, R. C.; Porto, I. M.; Gerlach, R. F.; Costa, F. N.; Braz, D.; Droppa, R.; de Sousa, F. B.

    2012-10-01

    With the introduction of fluoride as the main anticaries agent used in preventive dentistry, and perhaps an increase in fluoride in our food chain, dental fluorosis has become an increasing world-wide problem. Visible signs of fluorosis begin to become obvious on the enamel surface as opacities, implying some porosity in the tissue. The mechanisms that conduct the formation of fluorotic enamel are unknown, but should involve modifications in the basic physical-chemistry reactions of demineralization and remineralisation of the enamel of the teeth, which is the same reaction of formation of the enamel's hydroxyapatite (HAp) in the maturation phase. The increase of the amount of fluoride inside of the apatite will result in gradual increase of the lattice parameters. The aim of this work is to characterize the healthy and fluorotic enamel in human tooth using Synchrotron X-ray diffraction. All the scattering profile measurements were carried out at the X-ray diffraction beamline (XRD1) at the Brazilian Synchrotron Light Laboratory—LNLS, Campinas, Brazil. X-ray diffraction experiments were performed both in powder samples and polished surfaces. The powder samples were analyzed to obtain the characterization of a typical healthy enamel pattern. The polished surfaces were analyzed in specific areas that have been identified as fluorotic ones. X-ray diffraction data were obtained for all samples and these data were compared with the control samples and also with the literature data.

  6. Progress in Cell Marking for Synchrotron X-ray Computed Tomography

    NASA Astrophysics Data System (ADS)

    Hall, Christopher; Sturm, Erica; Schultke, Elisabeth; Arfelli, Fulvia; Menk, Ralf-Hendrik; Astolfo, Alberto; Juurlink, Bernhard H. J.

    2010-07-01

    Recently there has been an increase in research activity into finding ways of marking cells in live animals for pre-clinical trials. Development of certain drugs and other therapies crucially depend on tracking particular cells or cell types in living systems. Therefore cell marking techniques are required which will enable longitudinal studies, where individuals can be examined several times over the course of a therapy or study. The benefits of being able to study both disease and therapy progression in individuals, rather than cohorts are clear. The need for high contrast 3-D imaging, without harming or altering the biological system requires a non-invasive yet penetrating imaging technique. The technique will also have to provide an appropriate spatial and contrast resolution. X-ray computed tomography offers rapid acquisition of 3-D images and is set to become one of the principal imaging techniques in this area. Work by our group over the last few years has shown that marking cells with gold nano-particles (GNP) is an effective means of visualising marked cells in-vivo using x-ray CT. Here we report the latest results from these studies. Synchrotron X-ray CT images of brain lesions in rats taken using the SYRMEP facility at the Elettra synchrotron in 2009 have been compared with histological examination of the tissues. Some deductions are drawn about the visibility of the gold loaded cells in both light microscopy and x-ray imaging.

  7. Progress in Cell Marking for Synchrotron X-ray Computed Tomography

    SciTech Connect

    Hall, Christopher; Sturm, Erica; Schultke, Elisabeth; Arfelli, Fulvia; Astolfo, Alberto; Menk, Ralf-Hendrik; Juurlink, Bernhard H. J.

    2010-07-23

    Recently there has been an increase in research activity into finding ways of marking cells in live animals for pre-clinical trials. Development of certain drugs and other therapies crucially depend on tracking particular cells or cell types in living systems. Therefore cell marking techniques are required which will enable longitudinal studies, where individuals can be examined several times over the course of a therapy or study. The benefits of being able to study both disease and therapy progression in individuals, rather than cohorts are clear. The need for high contrast 3-D imaging, without harming or altering the biological system requires a non-invasive yet penetrating imaging technique. The technique will also have to provide an appropriate spatial and contrast resolution. X-ray computed tomography offers rapid acquisition of 3-D images and is set to become one of the principal imaging techniques in this area. Work by our group over the last few years has shown that marking cells with gold nano-particles (GNP) is an effective means of visualising marked cells in-vivo using x-ray CT. Here we report the latest results from these studies. Synchrotron X-ray CT images of brain lesions in rats taken using the SYRMEP facility at the Elettra synchrotron in 2009 have been compared with histological examination of the tissues. Some deductions are drawn about the visibility of the gold loaded cells in both light microscopy and x-ray imaging.

  8. Soft x-ray detection with diamond photoconductive detectors

    SciTech Connect

    Kania, D.R.; Pan, L.; Kornblum, H.; Bell, P.; Landen, O.N.; Pianetta, P.

    1990-05-04

    Photoconductive detectors fabricated from natural lla diamonds have been used to measure the x-ray power emitted from laser produced plasmas. The detector was operated without any absorbing filters to distort the x-ray power measurement. The 5.5 eV bandgap of the detector material practically eliminates its sensitivity to scattered laser radiation thus permitting filterless operation. The detector response time or carrier life time was 90 ps. Excellent agreement was achieved between a diamond PCD and a multichannel photoemissive diode array in the measurement of radiated x-ray power and energy. 4 figs.

  9. Synchrotron X-ray Investigations of Mineral-Microbe-Metal Interactions

    SciTech Connect

    Kemner, Kenneth M.; O'Loughlin, Edward J.; Kelly, Shelly D.; Boyanov, Maxim I.

    2008-06-06

    Interactions between microbes and minerals can play an important role in metal transformations (i.e. changes to an element's valence state, coordination chemistry, or both), which can ultimately affect that element's mobility. Mineralogy affects microbial metabolism and ecology in a system; microbes, in turn, can affect the system's mineralogy. Increasingly, synchrotron-based X-ray experiments are in routine use for determining an element's valence state and coordination chemistry, as well as for examining the role of microbes in metal transformations.

  10. Deconstructing the Spectrum of the Soft X-ray Background

    NASA Technical Reports Server (NTRS)

    Kuntz, K. D.; Snowden, S. L.

    2000-01-01

    The soft X-ray background in the 0.1-1.0 keV band is known to be produced by at least three sources; the Local Hot Bubble (LHB), the extragalactic power law (EPL), and a seemingly galactic component that lies outside the bulk of the absorption that is due to the ISM of the galactic disk. This last component, which we call the Trans-Absorption Emission (TAE), has been modeled by a number of groups who have derived disparate measures of its temperature. The differences have arisen from differing assumptions about the structure of the emitting gas and unrecognized methodological difficulties. In particular, spectral fitting methods do not uniquely separate the TAE from the foreground emission that is due the LHB. This "degeneracy" can be resolved using the angular variation of the absorption of the TAE. We show that the TAE cannot be characterized by a single thermal component; no single-component model can be consistent with both the spectral energy distribution of the TAE emission and the angular variation due to absorption by the galactic disk. We use the angular anticorrelation of the ROSAT All-Sky Survey with the galactic absorption to separate local from distant emission components, and to fit the spectral energy distribution of the resulting distant emission. We find that the emission is best described by a two-thermal-component model with logT(sub S) = 6.06(sup +0.14, sub -0.12) and log T(sub H) = 6.42(sup +0.14, sub -0.12). This two-thermal-component TAE fits the ROSAT spectral energy distribution significantly better than single-component models, and is consistent with both angular variation and spectral constraints.

  11. SASE3: soft x-ray beamline at European XFEL

    NASA Astrophysics Data System (ADS)

    La Civita, Daniele; Gerasimova, Natalia; Sinn, Harald; Vannoni, Maurizio

    2014-09-01

    The European XFEL in Hamburg will be comprised of a linear accelerator and three Free-Electron-Laser beamlines (SASE1, SASE2 and SASE3) covering the energy range from 250 eV to 24 keV. It will provide up to 2700 pulses in trains of 600 microsecond duration at a repetition rate of 10 Hz. SASE3 beamline is the soft X-ray beamline (0.25 - 3 keV) and delivers photon pulses to SQS (Small Quantum System) and SCS (Spectroscopy & Coherent Scattering) experiments. The beamline is able to operate in both monochromatic and non-monochromatic mode. The latter provides the inherent FEL bandwidth at higher intensities. The beamline from photon source to experimental station is about 450 m long. The length of the beamline is related to the optics single-shotdamage issue. The almost diffraction-limited beam is propagated along the beamline with very long (up to 800 mm clear aperture), cooled (with eutectic bath) and super-polished (50 nrad RMS slope error and less than 3 nm PV residual height error) mirrors. The VLS-PG (variable line spacing - plane grating) monochromator covers the entire beamline energy range and its optical design is guided by the optimization of the energy resolving power, the minimization of the pulse broadening and the maximization of optics damage tolerance. Grating substrates are 530 mm long, eutectic cooled and present outstanding surface quality. The VLS parameters of the blazed profile are also a real challenge under manufacturing and measuring point of view. Adaptive optics in the horizontal (the second offset mirror) and vertical (monochromator premirror) plane are foreseen in the optical layout to increase the beamline tunability and to preserve the highly coherent beam properties. Beamline optical design, expected performance and also mechanical aspects of main beamline components are reported.

  12. Examination for optimization of synchrotron radiation spectrum for the x ray depth lithography

    NASA Astrophysics Data System (ADS)

    Dany, Raimund

    1992-06-01

    The effect of reducing the vertical distribution of synchrotron radiation on its spectral distribution is examined through resin irradiation. The resulting filter effect is compared to that of absorption filters. Transmission coefficients of titanium, gold, and polyamide were calculated from linear absorption coefficients with the Beer law. The use of a diaphragm in X-ray depth lithography, which is the first step of the LIGA (Lithography Galvanoforming Molding) process, is discussed. A calorimetric device for determining the synchrotron radiation power and distribution was developed and tested. Measurements at the ELSA storage ring show a strong dependence of the vertical emittance on the electron current.

  13. Synchrotron X-ray CT characterization of titanium parts fabricated by additive manufacturing. Part I. Morphology.

    PubMed

    Scarlett, Nicola Vivienne Yorke; Tyson, Peter; Fraser, Darren; Mayo, Sheridan; Maksimenko, Anton

    2016-07-01

    Synchrotron X-ray tomography has been applied to the study of titanium parts fabricated by additive manufacturing (AM). The AM method employed here was the Arcam EBM(®) (electron beam melting) process which uses powdered titanium alloy, Ti64 (Ti alloy with approximately 6%Al and 4%V), as the feed and an electron beam for the sintering/welding. The experiment was conducted on the Imaging and Medical Beamline of the Australian Synchrotron. Samples were chosen to examine the effect of build direction and complexity of design on the surface morphology and final dimensions of the piece.

  14. Synchrotron based X-ray fluorescence activities at Indus-2: An overview

    SciTech Connect

    Tiwari, M. K.

    2014-04-24

    X-Ray fluorescence (XRF) spectrometry is a powerful non-destructive technique for elemental analysis of materials at bulk and trace concentration levels. Taking into consideration several advantages of the synchrotron based XRF technique and to fulfill the requirements of Indian universities users we have setup a microfocus XRF beamline (BL-16) on Indus-2 synchrotron light source. The beamline offers a wide range of usages – both from research laboratories and industries; and for researchers working in diverse fields. A brief overview of the measured performance of the beamline, design specifications including various attractive features and recent research activities carried out on the BL-16 beamline are presented.

  15. Understanding the instrumental profile of synchrotron radiation X-ray powder diffraction beamlines.

    PubMed

    Rebuffi, Luca; Sánchez Del Río, Manuel; Busetto, Edoardo; Scardi, Paolo

    2017-05-01

    A Monte Carlo algorithm has been developed to calculate the instrumental profile function of a powder diffraction synchrotron beamline. Realistic models of all optical elements are implemented in a ray-tracing software. The proposed approach and the emerging paradigm have been investigated and verified for several existing X-ray powder diffraction beamlines. The results, which can be extended to further facilities, show a new and general way of assessing the contribution of instrumental broadening to synchrotron radiation data, based on ab initio simulations.

  16. XDS: a flexible beamline for X-ray diffraction and spectroscopy at the Brazilian synchrotron.

    PubMed

    Lima, F A; Saleta, M E; Pagliuca, R J S; Eleotério, M A; Reis, R D; Fonseca Júnior, J; Meyer, B; Bittar, E M; Souza-Neto, N M; Granado, E

    2016-11-01

    The majority of the beamlines at the Brazilian Synchrotron Light Source Laboratory (LNLS) use radiation produced in the storage-ring bending magnets and are therefore currently limited in the flux that can be used in the harder part of the X-ray spectrum (above ∼10 keV). A 4 T superconducting multipolar wiggler (SCW) was recently installed at LNLS in order to improve the photon flux above 10 keV and fulfill the demands set by the materials science community. A new multi-purpose beamline was then installed at the LNLS using the SCW as a photon source. The XDS is a flexible beamline operating in the energy range between 5 and 30 keV, designed to perform experiments using absorption, diffraction and scattering techniques. Most of the work performed at the XDS beamline concentrates on X-ray absorption spectroscopy at energies above 18 keV and high-resolution diffraction experiments. More recently, new setups and photon-hungry experiments such as total X-ray scattering, X-ray diffraction under high pressures, resonant X-ray emission spectroscopy, among others, have started to become routine at XDS. Here, the XDS beamline characteristics, performance and a few new experimental possibilities are described.

  17. Tracking picosecond molecular dynamics in solution using a suite of synchrotron-x-ray spectroscopic tools

    NASA Astrophysics Data System (ADS)

    March, Anne Marie; Doumy, Gilles; Kanter, Elliot P.; Lehmann, Stefan; Moonshiram, Dooshaye; Southworth, Stephen H.; Young, Linda; Assefa, Tadesse A.; Bressler, Christian; Gawelda, Wojciech; Németh, Zoltán; Vankó, György

    2015-03-01

    Laser-pump, X-ray-probe techniques are powerful tools for exploring molecular structural changes that occur in complex environments such as solutions, during a photo-initiated reaction. We are developing such methods using hard x-rays from the Advanced Photon Source, combining x-ray emission spectroscopy and x-ray absorption spectroscopy as probes of electronic and geometric structure and using high-power, MHz lasers as pumps. The high-duty-cycle pump-probe measurements efficiently utilize the synchrotron x-ray flux and enable high-fidelity measurements of the structures of transient intermediates. We present measurements on the model system [Fe(II)(CN)6]4- (ferrocyanide) in an aqueous solution after excitation with 355 nm and 266 nm laser light. The system undergoes two wavelength dependent reactions: photooxidation and photoaquation. Iron K-edge absorption spectra were obtained along with iron emission spectra. Our data support the presence of a previously unobserved pentacoordinated intermediate species in the photoaquation reaction. Its lifetime has been measured to be 4.6 ns and details of its structure will be discussed. The work was supported by the U.S. Department of Energy, Office of Science, Chemical Sciences, Geosciences, and Biosciences Division.

  18. Dosimetry and Radiobiology of Synchrotron-Produced Ultrasoft X-Rays

    NASA Astrophysics Data System (ADS)

    Meger, Carol Mary

    Ultrasoft X-rays provide a unique tool to study the mechanism of radiation damage in biological systems. Experimenters have used X-ray tubes with titanium, copper, silver, magnesium, aluminum and carbon targets to generate characteristic X-rays of these materials to irradiate a variety of mammalian cell lines. Limitations in the photon intensity and the available energies from X-ray tube sources prevent definitive characterization of a relationship between photon energy and biological damage. Synchrotron radiation is a useful alternative source of low energy photons since it is available with high intensity over a continuous spectrum. A system was established including an appropriate dosimetry protocol and a workable system for conducting biology studies. A characterization of the system including spectral and intensity properties of the photon beam is presented. Cell survival curves for C3H/10T1/2 show increased efficiency for cell killing for 1-4 keV photons with respect to 250 kVp X-rays.

  19. Versatile, reprogrammable area pixel array detector for time-resolved synchrotron x-ray applications

    SciTech Connect

    Gruner, Sol

    2010-05-01

    The final technical report for DOE grant DE-SC0004079 is presented. The goal of the grant was to perform research, development and application of novel imaging x-ray detectors so as to effectively utilize the high intensity and brightness of the national synchrotron radiation facilities to enable previously unfeasible time-resolved x-ray research. The report summarizes the development of the resultant imaging x-ray detectors. Two types of detector platforms were developed: The first is a detector platform (called a Mixed-Mode Pixel Array Detector, or MM-PAD) that can image continuously at over a thousand images per second while maintaining high efficiency for wide dynamic range signals ranging from 1 to hundreds of millions of x-rays per pixel per image. Research on an even higher dynamic range variant is also described. The second detector platform (called the Keck Pixel Array Detector) is capable of acquiring a burst of x-ray images at a rate of millions of images per second.

  20. Deciphering the Complex Chemistry of Deep-Ocean Particles Using Complementary Synchrotron X-ray Microscope and Microprobe Instruments.

    PubMed

    Toner, Brandy M; German, Christopher R; Dick, Gregory J; Breier, John A

    2016-01-19

    amounts of material, (3) simplify the chemical complexity of particles or sets of particles with a focused-beam, providing spatial resolution over 6 orders of magnitude (nanometer to millimeter), (4) provide elemental specificity for elements in the soft-, tender-, and hard-X-ray energies, (5) switch rapidly among elements of interest, and (6) function in the presence of water and gases. Synchrotron derived data sets are discussed in the context of important advances in deep-ocean technology, sample handling and preservation, molecular microbiology, and coupled physical-chemical-biological modeling. Particle chemistry, size, and morphology are all important in determining whether particles are reactive with dissolved constituents, provide substrates for microbial respiration and growth, and are delivered to marine sediments or dispersed by deep-ocean currents.