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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. 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.

  7. 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.

  8. 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

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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

  14. 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.

  15. 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

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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

  3. 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.

  4. 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.

  5. 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.

  6. 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

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  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. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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

  2. 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.

  3. 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.

  4. 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

  5. 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.

  6. 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

  7. 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.

  8. 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.

  9. 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.

  10. 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

  11. 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.

  12. 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.

  13. 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

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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

  1. 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).

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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

  14. 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)

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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)

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. Synchrotron x-ray ultrafast x-ray imaging on dynamic multiphase flow studies

    NASA Astrophysics Data System (ADS)

    Wang, Yujie; Fezzaa, Kamel; Wang, Jin; Im, Kyoung-Su

    2007-03-01

    To overcome the long-exposure time of x-ray imaging for liquid systems. In the past year, we have developed the first ultrafast white-beam synchrotron x-ray phase-contrast imaging technique in the world. With its unprecedented temporal (0.5 μs) and spatial resolutions (1 μm), this new technique has already shown great promises in the study of complex fluid mechanical systems. It can probe complex surface morphology and transient dynamics of these interfaces of fluid mechanical systems without the nuisance of multiple scattering. This technique is a big step forward in comparison to millisecond-temporal and micrometer-spatial imaging resolutions normally achieved at various synchrotron sources. With the development of this new technique, we can already carry out research in fluid mechanical systems in competition with world-leading research groups. Our study of the primary breakup process of a coaxial air-assisted liquid jet revealed that the dynamics is dominated by a ``liquid membrane breakup'' process instead of a simple ``ligament mediated breakup'' process owing to our far superior temporal and spatial resolutions. This observation will naturally lead to a cascade idea for the unified treatment of liquid jets, droplets, and liquid membranes breakup mechanism.

  8. 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.

  9. 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.

  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. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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

  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

    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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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

  5. 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.

  6. 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

  7. 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).

  8. 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.

  9. 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.

  10. 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.

  11. 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

  12. 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

  13. 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

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  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. 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.

  12. 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.

  13. 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.

  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. 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.

  16. 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.

  17. 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.

  18. [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%.

  19. 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

  20. 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.

  1. 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).

  2. 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).

  3. 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.

  4. 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

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. Coherent X-ray diffraction from collagenous soft tissues

    SciTech Connect

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

    2009-09-11

    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.

  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. 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.

  12. 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.

  13. 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.

  14. 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).

  15. X-ray absorption and soft x-ray fluorescence analysis of KDP optics

    SciTech Connect

    Nelson, A J; van Buuren, T; Miller, E; Land, T A; Bostedt, C; Franco, N; Whitman, P K; Baisden, P A; Terminello, L J; Callcott, T A

    2000-08-09

    Potassium Dihydrogen Phosphate (KDP) is a non-linear optical material used for laser frequency conversion and optical switches. Unfortunately, when KDP crystals are coated with a porous silica anti-reflection coating [1] and then exposed to ambient humidity, they develop dissolution pits [2,3]. Previous investigations [2] have shown that thermal annealing renders KDP optics less susceptible to pitting suggesting that a modification of surface chemistry has occurred. X-ray absorption and fluorescence were used to characterize changes in the composition and structure of KDP optics as a function of process parameters. KDP native crystals were also analyzed to provide a standard basis for interpretation. Surface sensitive total electron yield and bulk sensitive fluorescence yield from the K 2p, P 2p (L{sub 2,3}-edge) and O 1s (K-edge) absorption edges were measured at each process step. Soft X-ray fluorescence was also used to observe changes associated with spectral differences noted in the absorption measurements. Results indicate that annealing at 160 C dehydrates the surface of KDP resulting in a metaphosphate surface composition with K:P:O = 1:1:3.

  16. 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.

  17. 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.

  18. 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.

  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. 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.

  1. 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.

  2. 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.

  3. 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.

  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. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. Soft X-Ray Observations of a Complete Sample of X-Ray--selected BL Lacertae Objects: Erratum

    NASA Astrophysics Data System (ADS)

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

    1996-07-01

    In the paper, "Soft X-Ray Observations of a Complete Sample of X-Ray- selected BL Lacertae Objects" by Eric S. Perlman, John T. Stocke, Q. Daniel Wang, and Simon L. Morris (ApJ, 456,451 [1996]), there is an error in Figure 5 (see Section 4.1). The corrected figure is given below. The discussion in the text and the conclusions of the paper are unaffected by this error, which occurred during the publication process. See Journal.

  17. 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.

  18. (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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

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

    PubMed

    Lu, L; Fan, D; 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; Luo, S N

    2014-07-01

    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.

  10. 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)

  11. 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.

  12. 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)

  13. 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.

  14. 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.

  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. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  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. 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.

  4. 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.

  5. 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.

  6. 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).

  7. 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.

  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. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. Surface Slope Metrology on Deformable Soft X-ray Mirrors

    SciTech Connect

    Yuan Sheng; Yashchuk, Valeriy V.; Celestre, Rich; Church, Matthew; McKinney, Wayne R.; Morrison, Greg; Warwick, Tony; Goldberg, Kenneth A.

    2010-06-23

    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.

  19. 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.

  20. 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.

  1. 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.

  2. 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

  3. 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.

  4. 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.

  5. 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.

  6. 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

  7. 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.

  8. 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

  9. 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

  10. 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

  11. 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.

  12. 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.

  13. 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.

  14. Multimodal hard X-ray imaging of a mammography phantom at a compact synchrotron light source.

    PubMed

    Schleede, Simone; Bech, Martin; Achterhold, Klaus; Potdevin, Guillaume; Gifford, Martin; Loewen, Rod; Limborg, Cecile; Ruth, Ronald; Pfeiffer, Franz

    2012-07-01

    The Compact Light Source is a miniature synchrotron producing X-rays at the interaction point of a counter-propagating laser pulse and electron bunch through the process of inverse Compton scattering. The small transverse size of the luminous region yields a highly coherent beam with an angular divergence of a few milliradians. The intrinsic monochromaticity and coherence of the produced X-rays can be exploited in high-sensitivity differential phase-contrast imaging with a grating-based interferometer. Here, the first multimodal X-ray imaging experiments at the Compact Light Source at a clinically compatible X-ray energy of 21 keV are reported. Dose-compatible measurements of a mammography phantom clearly demonstrate an increase in contrast attainable through differential phase and dark-field imaging over conventional attenuation-based projections.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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).

  2. 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

  3. 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.

  4. 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.

  5. 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.

  6. 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

  7. 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

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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

  8. 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.

  9. 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.

  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. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  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. 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.

  15. 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.

  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. 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.

  18. Magnetic soft x-ray microscopy-imaging fast spin dynamics inmagnetic nanostructures

    SciTech Connect

    Fischer, Peter; Kim, Dong-Hyun; Mesler, Brooke L.; Chao, Weilun; Sakdinawat, Anne E.; Anderson, Erik H.

    2007-06-01

    Magnetic soft X-ray microscopy combines 15nm spatial resolution with 70ps time resolution and elemental sensitivity. Fresnel zone plates are used as X-ray optics and X-ray magnetic circular dichroism serves as magnetic contrast mechanism. Thus scientifically interesting and technologically relevant low dimensional nanomagnetic systems can be imaged at fundamental length and ultrafast time scales in a unique way. Studies include magnetization reversal in magnetic multilayers, nanopatterned systems, vortex dynamics in nanoelements and spin current induced phenomena.

  19. Characterization of a next-generation piezo bimorph X-ray mirror for synchrotron beamlines

    PubMed Central

    Alcock, Simon G.; Nistea, Ioana; Sutter, John P.; Sawhney, Kawal; Fermé, Jean-Jacques; Thellièr, Christophe; Peverini, Luca

    2015-01-01

    Piezo bimorph mirrors are versatile active optics used on many synchrotron beamlines. However, many bimorphs suffer from the ‘junction effect’: a periodic deformation of the optical surface which causes major aberrations to the reflected X-ray beam. This effect is linked to the construction of such mirrors, where piezo ceramics are glued directly below the thin optical substrate. In order to address this problem, a next-generation bimorph with piezos bonded to the side faces of a monolithic substrate was developed at Thales-SESO and optimized at Diamond Light Source. Using metrology feedback from the Diamond-NOM, the optical slope error was reduced to ∼0.5 µrad r.m.s. for a range of ellipses. To maximize usability, a novel holder was built to accommodate the substrate in any orientation. When replacing a first-generation bimorph on a synchrotron beamline, the new mirror significantly improved the size and shape of the reflected X-ray beam. Most importantly, there was no evidence of the junction effect even after eight months of continuous beamline usage. It is hoped that this new design will reinvigorate the use of active bimorph optics at synchrotron and free-electron laser facilities to manipulate and correct X-ray wavefronts. PMID:25537582

  20. Characterization of a next-generation piezo bimorph X-ray mirror for synchrotron beamlines.

    PubMed

    Alcock, Simon G; Nistea, Ioana; Sutter, John P; Sawhney, Kawal; Fermé, Jean Jacques; Thellièr, Christophe; Peverini, Luca

    2015-01-01

    Piezo bimorph mirrors are versatile active optics used on many synchrotron beamlines. However, many bimorphs suffer from the `junction effect': a periodic deformation of the optical surface which causes major aberrations to the reflected X-ray beam. This effect is linked to the construction of such mirrors, where piezo ceramics are glued directly below the thin optical substrate. In order to address this problem, a next-generation bimorph with piezos bonded to the side faces of a monolithic substrate was developed at Thales-SESO and optimized at Diamond Light Source. Using metrology feedback from the Diamond-NOM, the optical slope error was reduced to ∼ 0.5 µrad r.m.s. for a range of ellipses. To maximize usability, a novel holder was built to accommodate the substrate in any orientation. When replacing a first-generation bimorph on a synchrotron beamline, the new mirror significantly improved the size and shape of the reflected X-ray beam. Most importantly, there was no evidence of the junction effect even after eight months of continuous beamline usage. It is hoped that this new design will reinvigorate the use of active bimorph optics at synchrotron and free-electron laser facilities to manipulate and correct X-ray wavefronts.

  1. Phase contrast X-ray synchrotron imaging: opening access to fossil inclusions in opaque amber.

    PubMed

    Lak, Malvina; Néraudeau, Didier; Nel, André; Cloetens, Peter; Perrichot, Vincent; Tafforeau, Paul

    2008-06-01

    A significant portion of Mesozoic amber is fully opaque. Biological inclusions in such amber are invisible even after polishing, leading to potential bias in paleoecological and phylogenetic studies. Until now, studies using conventional X-ray microtomography focused on translucent or semi-opaque amber. In these cases, organisms of interest were visualized prior to X-ray analyses. It was recently demonstrated that propagation phase contrast X-ray synchrotron imaging techniques are powerful tools to access invisible inclusions in fully opaque amber. Here we describe an optimized synchrotron microradiographic protocol that allowed us to investigate efficiently and rapidly large amounts of opaque amber pieces from Charentes (southwestern France). Amber pieces were imaged with microradiography after immersion in water, which optimizes the visibility of inclusions. Determination is not accurate enough to allow precise phylogenetic studies, but provides preliminary data on biodiversity and ecotypes distribution; phase contrast microtomography remains necessary for precise determination. Because the organisms are generally much smaller than the amber pieces, we optimized local microtomography by using a continuous acquisition mode (sample moving during projection integration). As tomographic investigation of all inclusions is not practical, we suggest the use of a synchrotron for a microradiographic survey of opaque amber, coupled with microtomographic investigations of the most valuable organisms.

  2. Soft x-ray circular dichroism and scattering using a modulated elliptically polarizing wiggler and double synchronous detection

    SciTech Connect

    Sutherland, J.C.; Polewski, K.; Monteleone, D.C.

    1998-01-23

    We have constructed an experimental station (beamline) at the National Synchrotron Light Source to measure circular dichroism (CD) using soft x-rays (250 {le} hv {le} 900 eV) from a time modulated elliptically polarizing wiggler. The polarization of the soft x-ray beam switches periodically between two opposite polarizations, hence permitting the use of phase-sensitive (lock-in) detection. While the wiggler can be modulated at frequencies up to 100 Hz, switching transients limit the actual practical frequency to {approx}25 Hz. With analog detection, switching transients are blocked by a chopper synchronized to the frequency and phase of the wiggler. The CD is obtained from the ratio of the signal recovered at the frequency of polarization modulation, f, to the average beam intensity, which is recovered by synchronous detection at frequency 2f.

  3. Data of low-dose phase-based X-ray imaging for in situ soft tissue engineering assessments

    PubMed Central

    Izadifar, Zohreh; Honaramooz, Ali; Wiebe, Sheldon; Belev, George; Chen, Xiongbiao; Chapman, Dean

    2016-01-01

    This article presents the data of using three phase-based X-ray imaging techniques to characterize biomaterial scaffold and soft tissues in situ, as reported in our study “Low-dose phase-based X-ray imaging techniques for in situ soft tissue engineering assessments” [1]. The examined parameters include the radiation dose, scan time, and image quality, which are all critical to longitudinal in situ live animal assessments. The data presented were obtained from three dimensional imaging of scaffolds in situ cartilage by means of synchrotron-based computed tomography-diffraction enhanced imaging (CT-DEI), analyzer based imaging (CT-ABI), and in-line phase contrast imaging (CT-PCI) at standard and low dose imaging modalities. PMID:26909381

  4. High-resolution, high-transmission soft x-ray spectrometer for the study of biological samples.

    PubMed

    Fuchs, O; Weinhardt, L; Blum, M; Weigand, M; Umbach, E; Bär, M; Heske, C; Denlinger, J; Chuang, Y-D; McKinney, W; Hussain, Z; Gullikson, E; Jones, M; Batson, P; Nelles, B; Follath, R

    2009-06-01

    We present a variable line-space grating spectrometer for soft x-rays that covers the photon energy range between 130 and 650 eV. The optical design is based on the Hettrick-Underwood principle and tailored to synchrotron-based studies of radiation-sensitive biological samples. The spectrometer is able to record the entire spectral range in one shot, i.e., without any mechanical motion, at a resolving power of 1200 or better. Despite its slitless design, such a resolving power can be achieved for a source spot as large as (30 x 3000) microm2, which is important for keeping beam damage effects in radiation-sensitive samples low. The high spectrometer efficiency allows recording of comprehensive two-dimensional resonant inelastic soft x-ray scattering (RIXS) maps with good statistics within several minutes. This is exemplarily demonstrated for a RIXS map of highly oriented pyrolytic graphite, which was taken within 10 min.

  5. Plane-grating flat-field soft x-ray spectrometer

    NASA Astrophysics Data System (ADS)

    Hague, C. F.; Underwood, J. H.; Avila, A.; Delaunay, R.; Ringuenet, H.; Marsi, M.; Sacchi, M.

    2005-02-01

    We describe a soft x-ray spectrometer covering the 120-800 eV range. It is intended for resonant inelastic x-ray scattering experiments performed at third generation synchrotron radiation (SR) facilities and has been developed with SOLEIL, the future French national SR source in mind. The Hettrick-Underwood principle is at the heart of the design using a combination of varied line-spacing plane grating and spherical-mirror to provide a flat-field image. It is slitless for optimum acceptance. This means the source size determines the resolving power. A spot size of ⩽5μm is planned at SOLEIL which, according to simulations, should ensure a resolving power ⩾1000 over the whole energy range. A 1024×1024 pixel charge-coupled device (CCD) with a 13μm×13μm pixel size is used. This is an improvement on the use of microchannel-plate detectors, both as concerns efficiency and spatial resolution. Additionally spectral line curvature is avoided by the use of a horizontal focusing mirror concentrating the beam in the nondispersing direction. It allows for readout using a binning mode to reduce the intrinsically large CCD readout noise. Preliminary results taken at beamlines at Elettra (Trieste) and at BESSY (Berlin) are presented.

  6. Design and performance of AERHA, a high acceptance high resolution soft x-ray spectrometer

    SciTech Connect

    Chiuzbăian, Sorin G. Hague, Coryn F.; Brignolo, Stefania; Baumier, Cédric; Lüning, Jan; Avila, Antoine; Delaunay, Renaud; Mariot, Jean-Michel; Jaouen, Nicolas; Polack, François; Thomasset, Muriel; Lagarde, Bruno; Nicolaou, Alessandro; Sacchi, Maurizio

    2014-04-15

    A soft x-ray spectrometer based on the use of an elliptical focusing mirror and a plane varied line spacing grating is described. It achieves both high resolution and high overall efficiency while remaining relatively compact. The instrument is dedicated to resonant inelastic x-ray scattering studies. We set out how this optical arrangement was judged best able to guarantee performance for the 50 − 1000 eV range within achievable fabrication targets. The AERHA (adjustable energy resolution high acceptance) spectrometer operates with an effective angular acceptance between 100 and 250 μsr (energy dependent) and a resolving power well in excess of 5000 according to the Rayleigh criterion. The high angular acceptance is obtained by means of a collecting pre-mirror. Three scattering geometries are available to enable momentum dependent measurements with 135°, 90°, and 50° scattering angles. The instrument operates on the Synchrotron SOLEIL SEXTANTS beamline which serves as a high photon flux 2 × 200 μm{sup 2} focal spot source with full polarization control.

  7. Design of Molecular Solar Cells via Feedback from Soft X-ray Spectroscopy

    SciTech Connect

    Himpsel, Franz J.

    2015-06-12

    Spectroscopy with soft X-rays was used to develop new materials and novel designs for solar cells and artificial photosynthesis. In order to go beyond the widely-used trial-and-error approach of gradually improving a particular design, we started from the most general layout of a solar cell (or a photo-electrochemical device) and asked which classes of materials are promising for best performance. For example, the most general design of a solar cell consists of a light absorber, an electron donor, and an electron acceptor. These are characterized by four energy levels, which were measured by a combination of spectroscopic X-ray techniques. Tuning synchrotron radiation to the absorption edges of specific elements provided element- and bond-selectivity. The spectroscopic results were complemented by state-of-the-art calculations of the electronic states. These helped explaining the observed energy levels and the orbitals associated with them. The calculations were extended to a large class of materials (for example thousands of porphyrin dye complexes) in order to survey trends in the energy level structure. A few highlights serve as examples: 1) Organic molecules combining absorber, donor, and acceptor with atomic precision. 2) Exploration of highly p-doped diamond films as inert, transparent electron donors. 3) Surface-sensitive characterization of nanorod arrays used as photoanodes in water splitting. 4) Computational design of molecular complexes for efficient solar cells using two photons.

  8. Design and performance of AERHA, a high acceptance high resolution soft x-ray spectrometer

    NASA Astrophysics Data System (ADS)

    Chiuzbǎian, Sorin G.; Hague, Coryn F.; Avila, Antoine; Delaunay, Renaud; Jaouen, Nicolas; Sacchi, Maurizio; Polack, François; Thomasset, Muriel; Lagarde, Bruno; Nicolaou, Alessandro; Brignolo, Stefania; Baumier, Cédric; Lüning, Jan; Mariot, Jean-Michel

    2014-04-01

    A soft x-ray spectrometer based on the use of an elliptical focusing mirror and a plane varied line spacing grating is described. It achieves both high resolution and high overall efficiency while remaining relatively compact. The instrument is dedicated to resonant inelastic x-ray scattering studies. We set out how this optical arrangement was judged best able to guarantee performance for the 50 - 1000 eV range within achievable fabrication targets. The AERHA (adjustable energy resolution high acceptance) spectrometer operates with an effective angular acceptance between 100 and 250 μsr (energy dependent) and a resolving power well in excess of 5000 according to the Rayleigh criterion. The high angular acceptance is obtained by means of a collecting pre-mirror. Three scattering geometries are available to enable momentum dependent measurements with 135°, 90°, and 50° scattering angles. The instrument operates on the Synchrotron SOLEIL SEXTANTS beamline which serves as a high photon flux 2 × 200 μm2 focal spot source with full polarization control.

  9. Tunable thin film polarizer for the vacuum ultraviolet and soft x-ray spectral regions

    SciTech Connect

    Yang, Minghong; Cobet, Christoph; Esser, Norbert

    2007-03-01

    A low pass polarizer that suppresses higher-order diffraction light from vacuum ultraviolet and soft x-ray monochromators is presented in this paper. This vacuum ultraviolet and soft x-ray polarizer is based on a concept of sandwiched metal-dielectric-metal triple reflection configuration. By appropriate optimization of material and angle of incidence, the proposed Au-SiC-Au polarizer demonstrates the capability of matching to desired cutoff edge of photon energy. Furthermore, the optimized soft x-ray polarizer shows the possibility to tune cutoff photon energy in a broadband spectral region ranging from 80 down to down to 20 eV.

  10. Soft X-Ray Emission from Alexandrite Laser-Matter-Interaction

    DTIC Science & Technology

    1993-07-15

    34AD-A267 905 NRL/MR/6681--93-7359 Soft X-ray Emission from Alexandrite Laser-Matter-Interaction P. G. BURKHALTER Dvnamit s of Solids Branch Condensed...Soft X-ray Emission from Alexandrite Laser-Matter-Interaction 6. AUTHOR(S) P.G. Burkhalter, D.J. Harter*, E.F. Gabl**, P. Bado**, and D.A. Newman*** 7...Proscribed by ANSI Std 230-13 290-102 SOFT X-RAY EMISSION FROM ALEXANDRITE LASER-MATTER-INTERACTION Accesion For NTIS CRA&I DTIC TAB Unannounced 5

  11. Energetics and timing of the hard and soft X-ray emissions in white light flares

    NASA Technical Reports Server (NTRS)

    Neidig, Donald F.; Kane, Sharad R.

    1993-01-01

    By comparing the light curves in optical, hard X-ray, and soft X-ray wavelengths for eight well-observed flares, we confirm previous results indicating that the white light flare (WLF) is associated with the flare impulsive phase. The WLF emission peaks within seconds after the associated hard X-ray peak, and nearly two minutes before the 1-8 A soft X-ray peak. It is further shown that the peak power in nonthermal electrons above 50 keV is typically an order of magnitude larger, and the power in 1-8 A soft X-rays radiated over 2pi sr, at the time of the WLF peak, is an order of magnitude smaller than the peak WLF power.

  12. Imaging nanoscale magnetic structures with polarized soft x-ray photons

    SciTech Connect

    Fischer, P.; Im, M.-Y.

    2010-01-18

    Imaging nanoscale magnetic structures and their fast dynamics is scientifically interesting and technologically of highest relevance. The combination of circularly polarized soft X-ray photons which provide a strong X-ray magnetic circular dichroism effect at characteristic X-ray absorption edges, with a high resolution soft X-ray microscope utilizing Fresnel zone plate optics allows to study in a unique way the stochastical behavior in the magnetization reversal process of thin films and the ultrafast dynamics of magnetic vortices and domain walls in confined ferromagnetic structures. Future sources of fsec short and high intense soft X-ray photon pulses hold the promise of magnetic imaging down to fundamental magnetic length and time scales.

  13. A CATALOG OF SOLAR X-RAY PLASMA EJECTIONS OBSERVED BY THE SOFT X-RAY TELESCOPE ON BOARD YOHKOH

    SciTech Connect

    Tomczak, M.; Chmielewska, E. E-mail: chmielewska@astro.uni.wroc.pl

    2012-03-01

    A catalog of X-ray plasma ejections (XPEs) observed by the Soft X-ray Telescope on board the Yohkoh satellite has been recently developed in the Astronomical Institute of University of Wroclaw. The catalog contains records of 368 events observed in years 1991-2001 including movies and cross-references to associated events like flares and coronal mass ejections (CMEs). One hundred sixty-three XPEs out of 368 in the catalog were not reported until now. A new classification scheme of XPEs is proposed in which morphology, kinematics, and recurrence are considered. The relation between individual subclasses of XPEs and the associated events was investigated. The results confirm that XPEs are strongly inhomogeneous, responding to different processes that occur in the solar corona. A subclass of erupting loop-like XPEs is a promising candidate to be a high-temperature precursor of CMEs.

  14. X-ray Imaging of Mucilaginous Sheath of Phytoplankton in Lake Biwa by Soft X-ray Microscope

    NASA Astrophysics Data System (ADS)

    Takemoto, K.; Ichise, S.; Ohigashi, T.; Namba, H.; Kihara, H.

    2011-09-01

    In Lake Biwa, the chemical oxygen demand (COD) index is increasing in spite of a decrease in the values of the biochemical oxygen demand (BOD) index. Picophytoplankton with a mucilaginous sheath is considered an important source of non-biodegradable organic compounds. In order to elucidate the mechanism, x-ray images of planktons inhabiting Lake Biwa were taken. The laboratory-cultured phytoplanktons with sheaths—Synechoccoucs, Microcystis wesenbergii, and Phormidium tenue—were observed by the soft x-ray microscope (BL12) of the Ritsumeikan University SR Center. Synechoccoucs cells were successfully observed with high contrast, and the mucilaginous sheath around the cell was also observed. However, although P. tenu cells were successfully observed with high contrast, it was impossible to confirm the mucilaginous sheath around the cell.

  15. Characterization of an x-ray phase contrast imaging system based on the miniature synchrotron MIRRORCLE-6X

    SciTech Connect

    Heekeren, Joop van; Kostenko, Alexander; Hanashima, Takayasu; Yamada, Hironari; Stallinga, Sjoerd; Offerman, S. Erik; Vliet, Lucas J. van

    2011-09-15

    Purpose: The implementation of in-line x-ray phase contrast imaging (PCI) for soft-tissue patient imaging is hampered by the lack of a bright and spatially coherent x-ray source that fits into the hospital environment. This article provides a quantitative characterization of the phase-contrast enhancement of a PCI system based on the miniature synchrotron technology MIRRORCLE-6X. Methods: The phase-contrast effect was measured using an edge response of a plexiglass plate as a function of the incident angle of radiation. We have developed a comprehensive x-ray propagation model based on the system's components, properties, and geometry in order to interpret the measurement data. Monte-Carlo simulations are used to estimate the system's spectral properties and resolution. Results: The measured ratio of the detected phase-contrast to the absorption contrast is currently in the range 100% to 200%. Experiments show that with the current implementation of the MIRRORCLE-6X, a target smaller than 30-40 {mu}m does not lead to a larger phase-contrast. The reason for this is that the fraction of x-rays produced by the material (carbon filament and glue) that is used for mounting the target in the electron beam is more than 25% of the total amount of x-rays produced. This increases the apparent source size. The measured phase-contrast is at maximum two times larger than the absorption contrast with the current set-up. Conclusions: Calculations based on our model of the present imaging system predict that the phase-contrast can be up to an order of magnitude larger than the absorption contrast in case the materials used for mounting the target in the electron beam do not (or hardly) produce x-rays. The methods described in this paper provide vital feedback for guiding future modifications to the design of the x-ray target of MIRRORCLE-type system and configuration of the in-line PCI systems in general.

  16. Taking X-ray Diffraction to the Limit: Macromolecular Structures from Femtosecond X-ray Pulses and Diffraction Microscopy of Cells with Synchrotron Radiation

    SciTech Connect

    Chapman, H N; Miao, J; Kirz, J; Sayre, D; Hodgson, K O

    2003-10-01

    The methodology of X-ray crystallography has recently been successfully extended to the structure determination of non-crystalline specimens. The phase problem was solved by using the oversampling method, which takes advantage of ''continuous'' diffraction pattern from non-crystalline specimens. Here we review the principle of this newly developed technique and discuss the ongoing experiments of imaging non-periodic objects, like cells and cellular structures using coherent and bright X-rays from the 3rd generation synchrotron radiation. In the longer run, the technique may be applied to image single biomolecules by using the anticipated X-ray free electron lasers. Computer simulations have so far demonstrated two important steps: (1) by using an extremely intense femtosecond X-ray pulse, a diffraction pattern can be recorded from a macromolecule before radiation damage manifests itself, and (2) the phase information can be ab initio retrieved from a set of calculated noisy diffraction patterns of single protein molecules.

  17. Synchrotron-based crystal structure, associated morphology of snail and bivalve shells by X-ray diffraction

    NASA Astrophysics Data System (ADS)

    Rao, D. V.; Gigante, G. E.; Kumar, Y. Manoj; Cesareo, R.; Brunetti, A.; Schiavon, N.; Akatsuka, T.; Yuasa, T.; Takeda, T.

    2016-10-01

    Synchrotron-based high-resolution X-ray powder diffraction spectra from the body parts of a snail and bivalve (CaCO3), have been recorded with Pilatus area detector. Experiments were performed at Desy, Hamburg, Germany, utilizing the Resonant and Diffraction beamline (P9), with 15 keV X-rays (λ=0.82666 Å). The external shell of these living organisms, is composed of calcium carbonate, which carries strong biological signal. It consists of some light elements, such as, Ca, C and O, which constitute part of the soft tissue and other trace elements. The knowledge of these diffraction patterns and hence the understanding of structures at molecular level are enormous. The application of synchrotron radiation to powder diffraction is well suited for samples of biological nature via changes in their patterns and also to investigate crystallographic phase composition. With the use of Rietveld refinement procedure, to the high-resolution diffraction spectra, we were able to extract the lattice parameters of orthorhombic polymorph of CaCO3, the most abundant mineral produced by these living organisms. The small size of the crystallite is a very important factor related to the biological structure. The natural model presents a combination of organic and inorganic phases with nanometer size. For the present study, we also used the scanning electron microscopy (SEM) to explore the associated morphology of the snail and bivalve.

  18. Center for X-ray Optics, 1988

    SciTech Connect

    Not Available

    1989-04-01

    This report briefly reviews the following topics: soft-x-ray imaging; reflective optics for hard x-rays; coherent XUV sources; spectroscopy with x-rays; detectors for coronary artery imaging; synchrotron-radiation optics; and support for the advanced light source.

  19. A Detailed Spatial and Spectral Study of Synchrotron X-rays from Supernova Remnants with Chandra

    NASA Astrophysics Data System (ADS)

    Bamba, Aya

    2004-01-01

    We present the first results of a systematic spatial and spectral X-ray study of small scale structures on the shock of five supernova remnants (Cas A, Kepler, Tycho, SN 1006, and RCW 86) and a super bubble (30 Dor C), with excellent spatial resolution of the Chandra X-ray observatory. All targets have synchrotron X-ray emission which concentrate on a very narrow region of the outer edge of the shock. The scale length of the region emitting synchrotron X-rays is incredibly small, less than 1% of the radius of the system both in the upstream and the downstream, in which smaller lengths are seen in the upstream than in the downstream. Together with the information of wide band spectra from radio to X-ray, both age-limited and loss-limited assumptions are checked for the acceleration history of all the SNRs. We found a possible magnetic field strength and configuration, and the maximum energy of accelerated electrons have been estimated for each target. The perpendicular magnetic field to the shock normal is accepted in all SNR cases, with highly turbulent magnetic field downstream. Comparing the samples, we found that the scale length of shocks grows as its age increases, in the same rate of Sedov similar solution for upstream (∝ t4/5) and in a faster rate for downstream (∝ t1/2). The energy density of magnetic field and cosmic rays evolve keeping an equipartition with the thermal and kinetic energies of the shock (∝ t-6/5) under the assumption that the system is in the age-limited case, implying that there are strong energy interaction between kinetic, thermal, magnetic field, and cosmic ray energy densities. The magnetic field is always near to perpendicular. These are the first results to estimate observationally the magnetic field and its direction, energy density of magnetic field and cosmic rays, and their evolutions.

  20. Biological imaging by soft x-ray diffraction microscopy

    DOE PAGES

    Shapiro, D.; Thibault, P.; Beetz, T.; ...

    2005-10-25

    We have used the method of x-ray diffraction microscopy to image the complex-valued exit wave of an intact and unstained yeast cell. The images of the freeze-dried cell, obtained by using 750-eV x-rays from different angular orientations, portray several of the cell's major internal components to 30-nm resolution. The good agreement among the independently recovered structures demonstrates the accuracy of the imaging technique. To obtain the best possible reconstructions, we have implemented procedures for handling noisy and incomplete diffraction data, and we propose a method for determining the reconstructed resolution. This work represents a previously uncharacterized application of x-ray diffractionmore » microscopy to a specimen of this complexity and provides confidence in the feasibility of the ultimate goal of imaging biological specimens at 10-nm resolution in three dimensions.« less

  1. Imaging cochlear soft tissue displacement with coherent x-rays

    NASA Astrophysics Data System (ADS)

    Rau, Christoph; Richter, Claus-Peter

    2015-10-01

    At present, imaging of cochlear mechanics at mid-cochlear turns has not been accomplished. Although challenging, this appears possible with partially coherent hard x-rays. The present study shows results from stroboscopic x-ray imaging of a test object at audio frequencies. The vibration amplitudes were quantified. In a different set of experiments, an intact and calcified gerbil temporal bone was used to determine displacements of the reticular lamina, tectorial membrane, and Reissner’s membrane with the Lucas and Kanade video flow algorithm. The experiments validated high frequency x-ray imaging and imaging in a calcified cochlea. The present work is key for future imaging of cochlear micromechanics at a high spatial resolution.

  2. Biological imaging by soft x-ray diffraction microscopy

    SciTech Connect

    Shapiro, D.; Thibault, P.; Beetz, T.; Elser, V.; Howells, M.; Jacobsen, C.; Kirz, J.; Lima, E.; Miao, H.; Neiman, A. M.; Sayre, D.

    2005-10-25

    We have used the method of x-ray diffraction microscopy to image the complex-valued exit wave of an intact and unstained yeast cell. The images of the freeze-dried cell, obtained by using 750-eV x-rays from different angular orientations, portray several of the cell's major internal components to 30-nm resolution. The good agreement among the independently recovered structures demonstrates the accuracy of the imaging technique. To obtain the best possible reconstructions, we have implemented procedures for handling noisy and incomplete diffraction data, and we propose a method for determining the reconstructed resolution. This work represents a previously uncharacterized application of x-ray diffraction microscopy to a specimen of this complexity and provides confidence in the feasibility of the ultimate goal of imaging biological specimens at 10-nm resolution in three dimensions.

  3. A fluorescence XAFS measurement instrument in the soft x-ray region toward observation under operando conditions

    SciTech Connect

    Honda, M. Baba, Y.; Shimoyama, I.; Sekiguchi, T.

    2015-03-15

    X-ray absorption fine structure (XAFS) measurements are widely used for the analysis of electronic structure. Generally, XAFS in the soft X-ray region is measured under vacuum, but chemical structures under vacuum are typically different from those under operando conditions, where chemical species exhibit their function. Here, we developed an XAFS measurement instrument, as a step toward operando fluorescent, which yields XAFS measurement using synchrotron radiation in the soft X-ray region. We applied this method to analyze the local electronic structure of the sulfur atoms in L-cysteine in different pH solutions. In water at pH 7, the hydrogen atom does not dissociate from the thiol (-SH) group in L-cysteine, which forms a structure surrounded by and interacting with water molecules. The XAFS spectrum of L-cysteine in solution was altered by changing the pH. At pH 9, the hydrogen atom dissociated and a thiolate anion was formed. Although the -SH group was oxidized to SO{sub 4}{sup 2−} when L-cysteine was adsorbed on a metal surface and dried, no oxidation was observed in solution. This may be because the water molecules were densely packed and protected the -SH group from oxidation. Our results show that this instrument aimed toward operando fluorescence XAFS measurements in the soft X-ray region is useful for structural analysis of sulfur atoms in organic molecules in air and in solution. The instrument will be applied to the structural analysis of materials containing elements that have absorption edges in soft X-ray region, such as phosphorus and alkali metals (potassium and cesium). It will be also particularly useful for the analysis of samples that are difficult to handle under vacuum and materials that have specific functions in solution.

  4. Combined X-ray fluorescence and absorption computed tomography using a synchrotron beam

    NASA Astrophysics Data System (ADS)

    Hall, C.

    2013-06-01

    X-ray computed tomography (CT) and fluorescence X-ray computed tomography (FXCT) using synchrotron sources are both useful tools in biomedical imaging research. Synchrotron CT (SRCT) in its various forms is considered an important technique for biomedical imaging since the phase coherence of SR beams can be exploited to obtain images with high contrast resolution. Using a synchrotron as the source for FXCT ensures a fluorescence signal that is optimally detectable by exploiting the beam monochromaticity and polarisation. The ability to combine these techniques so that SRCT and FXCT images are collected simultaneously, would bring distinct benefits to certain biomedical experiments. Simultaneous image acquisition would alleviate some of the registration difficulties which comes from collecting separate data, and it would provide increased information about the sample: functional X-ray images from the FXCT, with the morphological information from the SRCT. A method is presented for generating simultaneous SRCT and FXCT images. Proof of principle modelling has been used to show that it is possible to recover a fluorescence image of a point-like source from an SRCT apparatus by suitably modulating the illuminating planar X-ray beam. The projection image can be successfully used for reconstruction by removing the static modulation from the sinogram in the normal flat and dark field processing. Detection of the modulated fluorescence signal using an energy resolving detector allows the position of a fluorescent marker to be obtained using inverse reconstruction techniques. A discussion is made of particular reconstruction methods which might be applied by utilising both the CT and FXCT data.

  5. Exploring the Hard and Soft X-ray Emission of Magnetic Cataclysmic Variables

    NASA Astrophysics Data System (ADS)

    de Martino, D.; Anzolin, G.; Bonnet-Bidaud, J.-M.; Falanga, M.; Matt, G.; Mouchet, M.; Mukai, K.; Masetti, N.

    2009-05-01

    A non-negligible fraction of galactic hard (>20 keV) X-ray sources were identified as CVs of the magnetic Intermediate Polar type in INTEGRAL, SWIFT and RXTE surveys, that suggests a still hidden but potentially important population of faint hard X-ray sources. Simbol-X has the unique potential to simultaneously characterize their variable and complex soft and hard X-ray emission thus allowing to understand their putative role in galactic populations of X-ray sources.

  6. Evaluating scintillator performance in time-resolved hard X-ray studies at synchrotron light sources

    PubMed Central

    Rutherford, Michael E.; Chapman, David J.; White, Thomas G.; Drakopoulos, Michael; Rack, Alexander; Eakins, Daniel E.

    2016-01-01

    The short pulse duration, small effective source size and high flux of synchrotron radiation is ideally suited for probing a wide range of transient deformation processes in materials under extreme conditions. In this paper, the challenges of high-resolution time-resolved indirect X-ray detection are reviewed in the context of dynamic synchrotron experiments. In particular, the discussion is targeted at two-dimensional integrating detector methods, such as those focused on dynamic radiography and diffraction experiments. The response of a scintillator to periodic synchrotron X-ray excitation is modelled and validated against experimental data collected at the Diamond Light Source (DLS) and European Synchrotron Radiation Facility (ESRF). An upper bound on the dynamic range accessible in a time-resolved experiment for a given bunch separation is calculated for a range of scintillators. New bunch structures are suggested for DLS and ESRF using the highest-performing commercially available crystal LYSO:Ce, allowing time-resolved experiments with an interframe time of 189 ns and a maximum dynamic range of 98 (6.6 bits). PMID:27140147

  7. Evaluating scintillator performance in time-resolved hard X-ray studies at synchrotron light sources.

    PubMed

    Rutherford, Michael E; Chapman, David J; White, Thomas G; Drakopoulos, Michael; Rack, Alexander; Eakins, Daniel E

    2016-05-01

    The short pulse duration, small effective source size and high flux of synchrotron radiation is ideally suited for probing a wide range of transient deformation processes in materials under extreme conditions. In this paper, the challenges of high-resolution time-resolved indirect X-ray detection are reviewed in the context of dynamic synchrotron experiments. In particular, the discussion is targeted at two-dimensional integrating detector methods, such as those focused on dynamic radiography and diffraction experiments. The response of a scintillator to periodic synchrotron X-ray excitation is modelled and validated against experimental data collected at the Diamond Light Source (DLS) and European Synchrotron Radiation Facility (ESRF). An upper bound on the dynamic range accessible in a time-resolved experiment for a given bunch separation is calculated for a range of scintillators. New bunch structures are suggested for DLS and ESRF using the highest-performing commercially available crystal LYSO:Ce, allowing time-resolved experiments with an interframe time of 189 ns and a maximum dynamic range of 98 (6.6 bits).

  8. Study on Dual-Energy X-ray Computed Tomography using Synchrotron Radiation

    NASA Astrophysics Data System (ADS)

    Tsunoo, T.; Torikoshi, M.; Endo, M.; Natsuhori, M.; Kakizaki, T.; Yamada, N.; Itoh, N.; Uesugi, K.; Yagi, N.

    2004-05-01

    The electron density is one of the most important elements for the treatment planning in the radiotherapy, because this information is used for the range estimation of the heavy-ion beam. In order to measure more precise electron density, we have developed the dual-energy x-ray CT system using synchrotron radiation. The x-ray detector consists of 256 × 96 scintillator-array. It can take more than a hundred projection images per second. The response of the detector to x-rays was proved to be linear up to at least 1013 photon/pixel. The experiments were carried out using two monochromatic x-rays of 40 keV and 70 keV at the beam-line BL20B2 of SPring-8. As the results from samples of water, ethanol and solutions of dipotassium hydrogenphosphate with five concentrations, the electron densities measured in the dual-energy x-ray CT method were in agreement with the theoretical values by about ± 1%. This is almost the same level as that achieved by the one-dimensional CT system we developed previously. In addition, a sample of kidney of a pig fixed by formalin neutral buffer solution was used to distinguish the tissues in the CT images based on the electron density and the effective atomic number that was additionally obtained in the dual-energy x-ray CT. It suggested that renal pelvis was enriched with adipose tissue, and it was difficult to distinguish renal cortex and renal medulla.

  9. Study on Dual-Energy X-ray Computed Tomography using Synchrotron Radiation

    SciTech Connect

    Tsunoo, T.; Torikoshi, M.; Endo, M.; Natsuhori, M.; Kakizaki, T.; Yamada, N.; Itoh, N.; Uesugi, K.; Yagi, N.

    2004-05-12

    The electron density is one of the most important elements for the treatment planning in the radiotherapy, because this information is used for the range estimation of the heavy-ion beam. In order to measure more precise electron density, we have developed the dual-energy x-ray CT system using synchrotron radiation. The x-ray detector consists of 256 x 96 scintillator-array. It can take more than a hundred projection images per second. The response of the detector to x-rays was proved to be linear up to at least 1013 photon/pixel. The experiments were carried out using two monochromatic x-rays of 40 keV and 70 keV at the beam-line BL20B2 of SPring-8. As the results from samples of water, ethanol and solutions of dipotassium hydrogenphosphate with five concentrations, the electron densities measured in the dual-energy x-ray CT method were in agreement with the theoretical values by about {+-} 1%. This is almost the same level as that achieved by the one-dimensional CT system we developed previously. In addition, a sample of kidney of a pig fixed by formalin neutral buffer solution was used to distinguish the tissues in the CT images based on the electron density and the effective atomic number that was additionally obtained in the dual-energy x-ray CT. It suggested that renal pelvis was enriched with adipose tissue, and it was difficult to distinguish renal cortex and renal medulla.

  10. Time-resolved soft X-ray microscopy of magnetic nanostructures at the P04 beamline at PETRA III

    NASA Astrophysics Data System (ADS)

    Wessels, P.; Ewald, J.; Wieland, M.; Nisius, T.; Abbati, G.; Baumbach, S.; Overbuschmann, J.; Vogel, A.; Neumann, A.; Viefhaus, J.; Oepen, H. P.; Meier, G.; Wilhein, T.; Drescher, M.

    2014-04-01

    We present first time-resolved measurements of a new mobile full-field transmission microscope [1] obtained at the soft X-ray beamline P04 at the high brilliance synchrotron radiation source PETRA III. A nanostructured magnetic permalloy (Ni80Fe20) sample can be excited by the magnetic field of a 400 ps full width at half maximum (FWHM) long electric current pulse in a coplanar waveguide. The full-field soft X-ray microscope successively probes the time evolution of the sample magnetization via X-ray magnetic circular dichroism (XMCD) [2] spectromicroscopy in a pump-probe scheme by varying the delay between pump and probe pulses electronically. Static and transient magnetic fields of a permanent magnet and a coil are available in the sample plane to reset the system and to provide external offset fields. The microscope generates a flat-top illumination field of 20 μm diameter by using a grating condenser [3] and the sample plane is directly imaged by a micro zone plate with 60 nm resolution onto a 2D gateable X-ray detector to select the particular bunch in the storage ring that contains the dynamic information. The setup is built into a mobile endstation vacuum system with in-house developed three-axis piezo motorized stages for high accuracy positioning of all microscopy-components inside the chambers.

  11. Influence of the metallic contact in extreme-ultraviolet and soft x-ray diamond based Schottky photodiodes

    NASA Astrophysics Data System (ADS)

    Ciancaglioni, I.; Di Venanzio, C.; Marinelli, Marco; Milani, E.; Prestopino, G.; Verona, C.; Verona-Rinati, G.; Angelone, M.; Pillon, M.; Tartoni, N.

    2011-09-01

    X-ray and UV photovoltaic Schottky photodiodes based on single crystal diamond were recently developed at Rome "Tor Vergata" University laboratories. In this work, different rectifying metallic contact materials were thermally evaporated on the oxidized surface of intrinsic single crystal diamond grown by chemical vapor deposition. Their impact on the detection performance in the extreme UV and soft x-ray spectral regions was studied. The electrical characterization of the metal/diamond Schottky junctions was performed at room temperature by measuring the capacitance-voltage characteristics. The diamond photodiodes were then tested both over the extreme UV spectral region from 10 to 60 eV by using He-Ne DC gas discharge as a radiation source and toroidal vacuum monochromator, and in the soft x-ray range from 6 to 20 keV at the Diamond Light Source synchrotron x-ray beam-line in Harwell (UK). In both experimental setups, time response and spectral responsivity were analyzed for all the investigated Schottky contact materials. A good agreement between the experimental data and theoretical results from Monte Carlo simulations is found

  12. Soft x-ray source for nanostructure imaging using femtosecond-laser-irradiated clusters

    NASA Astrophysics Data System (ADS)

    Fukuda, Y.; Faenov, A. Ya.; Pikuz, T.; Kando, M.; Kotaki, H.; Daito, I.; Ma, J.; Chen, L. M.; Homma, T.; Kawase, K.; Kameshima, T.; Kawachi, T.; Daido, H.; Kimura, T.; Tajima, T.; Kato, Y.; Bulanov, S. V.

    2008-03-01

    The intense soft x-ray light source using the supersonic expansion of the mixed gas of He and CO2, when irradiated by a femtosecond Ti:sapphire laser pulse, is observed to enhance the radiation of soft x-rays from the CO2 clusters. Using this soft x-ray emissions, nanostructure images of 100-nm-thick Mo foils in a wide field of view (mm2 scale) with high spatial resolution (800nm ) are obtained with high dynamic range LiF crystal detectors. The local inhomogeneities of soft x-ray absorption by the nanometer-thick foils is measured with an accuracy of less than ±3%.

  13. Soft x-ray source for nanostructure imaging using femtosecond-laser-irradiated clusters

    SciTech Connect

    Fukuda, Y.; Kando, M.; Kotaki, H.; Daito, I.; Ma, J.; Chen, L. M.; Homma, T.; Kawase, K.; Kameshima, T.; Kawachi, T.; Daido, H.; Kimura, T.; Tajima, T.; Kato, Y.; Bulanov, S. V.; Faenov, A. Ya.; Pikuz, T.

    2008-03-24

    The intense soft x-ray light source using the supersonic expansion of the mixed gas of He and CO{sub 2}, when irradiated by a femtosecond Ti:sapphire laser pulse, is observed to enhance the radiation of soft x-rays from the CO{sub 2} clusters. Using this soft x-ray emissions, nanostructure images of 100-nm-thick Mo foils in a wide field of view (mm{sup 2} scale) with high spatial resolution (800 nm) are obtained with high dynamic range LiF crystal detectors. The local inhomogeneities of soft x-ray absorption by the nanometer-thick foils is measured with an accuracy of less than {+-}3%.

  14. Coherent soft x-ray generation in the water window with quasi-phase matching.

    PubMed

    Gibson, Emily A; Paul, Ariel; Wagner, Nick; Tobey, Ra'anan; Gaudiosi, David; Backus, Sterling; Christov, Ivan P; Aquila, Andy; Gullikson, Eric M; Attwood, David T; Murnane, Margaret M; Kapteyn, Henry C

    2003-10-03

    We demonstrate enhanced generation of coherent light in the "water window" region of the soft x-ray spectrum at 4.4 nanometers, using quasi-phase-matched frequency conversion of ultrafast laser pulses. By periodically modulating the diameter of a gas-filled hollow waveguide, the phase mismatch normally present between the laser light and the generated soft x-ray light can be partially compensated. This makes it possible to use neon gas as the nonlinear medium to coherently convert light up to the water window, illustrating that techniques of nonlinear optics can be applied effectively in the soft x-ray region of the spectrum. These results advance the prospects for compact coherent soft x-ray sources for applications in biomicroscopy and in chemical spectroscopy.

  15. Enhanced soft X-ray detection efficiencies for imaging microchannel plate detectors

    NASA Astrophysics Data System (ADS)

    Fraser, G. W.; Barstow, M. A.; Whiteley, M. J.; Wells, A.

    1982-12-01

    Although the microchannel plate (MCP) electron multipliers used in X-ray astronomy facilitate X-ray imaging with high spatial resolution, their intrinsic soft X-ray detection efficiencies of 1-10 percent are much lower than the near-unity values available with competing gas proportional counters. A high photoelectric yield material may be deposited on the MCP front surface and channel walls in order to enhance X-ray sensitivity at energies below a few keV. High 0.18-1.5 keV X-ray detection efficiencies are reported for MCPs bearing CsI deposition photocathodes, by which efficiency enhancement factors of up to 15 have been obtained. These results are especially pertinent to the sensitivity of such future X-ray astronomy experiments as the Roentgensatellit (Rosat) Wide Field Camera.

  16. Characterization of ion-induced radiation effects in nuclear materials using synchrotron x-ray techniques

    SciTech Connect

    Lang, Maik; Tracy, Cameron L.; Palomares, Raul I.; Zhang, Fuxiang; Severin, Daniel; Bender, Markus; Trautmann, Christina; Park, Changyong; Prakapenka, Vitali B.; Skuratov, Vladimir A.; Ewing, Rodney C.

    2015-05-01

    Recent efforts to characterize the nanoscale structural and chemical modifications induced by energetic ion irradiation in nuclear materials have greatly benefited from the application of synchrotron-based x-ray diffraction (XRD) and x-ray absorption spectroscopy (XAS) techniques. Key to the study of actinide-bearing materials has been the use of small sample volumes, which are particularly advantageous, as the small quantities minimize the level of radiation exposure at the ion-beam and synchrotron user facility. This approach utilizes energetic heavy ions (energy range: 100 MeV–3 GeV) that pass completely through the sample thickness and deposit an almost constant energy per unit length along their trajectory. High energy x-rays (25–65 keV) from intense synchrotron light sources are then used in transmission geometry to analyze ion-induced structural and chemical modifications throughout the ion tracks. We describe in detail the experimental approach for utilizing synchrotron radiation (SR) to study the radiation response of a range of nuclear materials (e.g., ThO2 and Gd2TixZr2–xO7). Also addressed is the use of high-pressure techniques, such as the heatable diamond anvil cell, as a new means to expose irradiated materials to well-controlled high-temperature (up to 1000 °C) and/or high-pressure (up to 50 GPa) conditions. Furthermore, this is particularly useful for characterizing the annealing kinetics of irradiation-induced material modifications.

  17. Characterization of ion-induced radiation effects in nuclear materials using synchrotron x-ray techniques

    DOE PAGES

    Lang, Maik; Tracy, Cameron L.; Palomares, Raul I.; ...

    2015-05-01

    Recent efforts to characterize the nanoscale structural and chemical modifications induced by energetic ion irradiation in nuclear materials have greatly benefited from the application of synchrotron-based x-ray diffraction (XRD) and x-ray absorption spectroscopy (XAS) techniques. Key to the study of actinide-bearing materials has been the use of small sample volumes, which are particularly advantageous, as the small quantities minimize the level of radiation exposure at the ion-beam and synchrotron user facility. This approach utilizes energetic heavy ions (energy range: 100 MeV–3 GeV) that pass completely through the sample thickness and deposit an almost constant energy per unit length along theirmore » trajectory. High energy x-rays (25–65 keV) from intense synchrotron light sources are then used in transmission geometry to analyze ion-induced structural and chemical modifications throughout the ion tracks. We describe in detail the experimental approach for utilizing synchrotron radiation (SR) to study the radiation response of a range of nuclear materials (e.g., ThO2 and Gd2TixZr2–xO7). Also addressed is the use of high-pressure techniques, such as the heatable diamond anvil cell, as a new means to expose irradiated materials to well-controlled high-temperature (up to 1000 °C) and/or high-pressure (up to 50 GPa) conditions. Furthermore, this is particularly useful for characterizing the annealing kinetics of irradiation-induced material modifications.« less

  18. Soft X-ray astronomy using grazing incidence optics

    NASA Technical Reports Server (NTRS)

    Davis, John M.

    1989-01-01

    The instrumental background of X-ray astronomy with an emphasis on high resolution imagery is outlined. Optical and system performance, in terms of resolution, are compared and methods for improving the latter in finite length instruments described. The method of analysis of broadband images to obtain diagnostic information is described and is applied to the analysis of coronal structures.

  19. Introduction of soft X-ray spectromicroscopy as an advanced technique for plant biopolymers research.

    PubMed

    Karunakaran, Chithra; Christensen, Colleen R; Gaillard, Cedric; Lahlali, Rachid; Blair, Lisa M; Perumal, Vijayan; Miller, Shea S; Hitchcock, Adam P

    2015-01-01

    Soft X-ray absorption spectroscopy coupled with nano-scale microscopy has been widely used in material science, environmental science, and physical sciences. In this work, the advantages of soft X-ray absorption spectromicroscopy for plant biopolymer research were demonstrated by determining the chemical sensitivity of the technique to identify common plant biopolymers and to map the distributions of biopolymers in plant samples. The chemical sensitivity of soft X-ray spectroscopy to study biopolymers was determined by recording the spectra of common plant biopolymers using soft X-ray and Fourier Transform mid Infrared (FT-IR) spectroscopy techniques. The soft X-ray spectra of lignin, cellulose, and polygalacturonic acid have distinct spectral features. However, there were no distinct differences between cellulose and hemicellulose spectra. Mid infrared spectra of all biopolymers were unique and there were differences between the spectra of water soluble and insoluble xylans. The advantage of nano-scale spatial resolution exploited using soft X-ray spectromicroscopy for plant biopolymer research was demonstrated by mapping plant cell wall biopolymers in a lentil stem section and compared with the FT-IR spectromicroscopy data from the same sample. The soft X-ray spectromicroscopy enables mapping of biopolymers at the sub-cellular (~30 nm) resolution whereas, the limited spatial resolution in the micron scale range in the FT-IR spectromicroscopy made it difficult to identify the localized distribution of biopolymers. The advantages and limitations of soft X-ray and FT-IR spectromicroscopy techniques for biopolymer research are also discussed.

  20. The possible effect of solar soft X rays on thermospheric nitric oxide

    NASA Technical Reports Server (NTRS)

    Siskind, D. E.; Barth, C. A.; Cleary, D. D.

    1990-01-01

    A rocket observation of nitric oxide in the lower thermosphere during a time of high solar activity is compared to the results of calculations from a one-dimensional photochemical model. A solar soft X-ray flux of 0.75 erg/sq cm/s is needed to explain the observed NO densities. This result supports the theory that the variation in the low-latitude thermospheric NO is caused by variation in solar soft X-rays.

  1. The X-ray eclipse geometry of the super-soft X-ray source CAL 87

    SciTech Connect

    Ribeiro, T.; Lopes de Oliveira, R.

    2014-09-01

    We explore XMM-Newton observations of the eclipsing super-soft X-ray source CAL 87 in order to map the accretion structures of the system. Indirect imaging techniques were applied in X-ray light curves to provide eclipse maps. The surface brightness distribution exhibits an extended and symmetric emission, and a feature is revealed from the hardest X-rays that is likely due to a bright spot. A rate of P-dot =(+6±2)×10{sup −10} for changes in the orbital period of the system was derived from the eclipses. There is no significant variation of the emission lines even during eclipses, arguing that the lines are formed in an extended region. The continuum emission dominates the decrease in flux that is observed during eclipses. The O VIII Lyα line reveals a broadening velocity that is estimated to be 365{sub −69}{sup +65} km s{sup –1} (at 1σ), marginal evidence for asymmetry in its profile, and sometimes shows evidence of double-peaked emission. Together, the results support that the wind-driven mass transfer scenario is running in CAL 87.

  2. Conical geometry for sagittal focusing as applied to X rays from synchrotrons

    SciTech Connect

    Ice, G.E.; Sparks, C.J.

    1993-06-01

    The authors describe a method for simultaneously focusing and monochromatization of X rays from a fan of radiation having up to 15 mrad divergence in one dimension. This geometry is well suited to synchrotron radiation sources at magnifications of one-fifth to two and is efficient for X-ray energies between 3 and 40 keV (0.48 and 6.4 fJ). The method uses crystals bent to part of a cone for sagittal focusing and allows for the collection of a larger divergence with less mixing of the horizontal into the vertical divergence than is possible with X-ray mirrors. They describe the geometry required to achieve the highest efficiency when a conical crystal follows a flat crystal in a nondispersive two-crystal monochromator. At a magnification of one-third, the geometry is identical to a cylindrical focusing design described previously. A simple theoretical calculation is shown to agree well with ray-tracing results. Minimum aberrations are observed at magnifications near one. Applications of the conical focusing geometry to existing and future synchrotron radiation facilities are discussed.

  3. In vivo microscopic x-ray imaging in rat and mouse using synchrotron radiation

    NASA Astrophysics Data System (ADS)

    Umetani, Keiji; Sakurai, Takashi; Kondoh, Takeshi

    2008-02-01

    A preclinical laboratory animal imaging modality similar to microangiography, with spatial resolution as high as 6 μm, has been developed at SPring-8 using an X-ray direct-conversion type detector incorporating an X-ray SATICON pickup tube. The imaging modality is intended to provide a basic understanding of disease mechanisms. In synchrotron radiation radiography, a long source-to-object distance and a small source spot can produce high-resolution images with spatial resolution in the micrometer range. Synchrotron radiation microangiography presents the main advantage of depicting the anatomy of small blood vessels with tens of micrometers' diameter. We performed cerebral microangiography in rats and mice and particularly undertook radiographical evaluation of changes in small arteries located deep in the brain; such vessels had not been observed and studied previously. Moreover, an X-ray direct-conversion type solid-state imager with spatial resolution in the micrometer range is being designed for large field-of-view imaging. This study is also intended to clarify requirements related to specifications of prospective solid-state image sensors.

  4. Trace element abundance determinations by Synchrotron X Ray Fluorescence (SXRF) on returned comet nucleus mineral grains

    NASA Technical Reports Server (NTRS)

    Flynn, G. J.; Sutton, S. R.

    1989-01-01

    Trace element analyses were performed on bulk cosmic dust particles by Proton Induced X Ray Emission (PIXE) and Synchrotron X Ray Fluorescence (SXRF). When present at or near chondritic abundances the trace elements K, Ti, Cr, Mn, Cu, Zn, Ga, Ge, Se, and Br are presently detectable by SXRF in particles of 20 micron diameter. Improvements to the SXRF analysis facility at the National Synchrotron Light Source presently underway should increase the range of detectable elements and permit the analysis of smaller samples. In addition the Advanced Photon Source will be commissioned at Argonne National Laboratory in 1995. This 7 to 8 GeV positron storage ring, specifically designed for high-energy undulator and wiggler insertion devices, will be an ideal source for an x ray microprobe with one micron spatial resolution and better than 100 ppb elemental sensitivity for most elements. Thus trace element analysis of individual micron-sized grains should be possible by the time of the comet nucleus sample return mission.

  5. Heat transfer issues in high-heat-load synchrotron x-ray beams

    SciTech Connect

    Khounsary, A.M.; Mills, D.M.

    1994-09-01

    In this paper, a short description of the synchrotron radiation x-ray sources and the associated power loads is given, followed by a brief description of typical synchrotron components and their heat load. It is emphasized that the design goals for most of these components is to limit (a) temperature, (b) stresses, or (c) strains in the system. Each design calls for a different geometry, material selection, and cooling scheme. Cooling schemes that have been utilized so far are primarily single phase and include simple macrochannel cooling, microchannel cooling, contact cooling, pin-post cooling, porous-flow cooling, jet cooling, etc. Water, liquid metals, and various cryogenic coolants have been used. Because the trend in x-ray beam development is towards brighter (i.e., more powerful) beams and assuming that no radical changes in the design of x-ray generating machines occurs in the next few years, it is fair to state that the utilization of various effective cooling schemes and, in particular, two-phase flow (e.g., subcooled boiling) warrants further investigation. This, however, requires a thorough examination of stability and reliability of two-phase flows for high-heat-flux components operating in ultrahigh vacuum with stringent reliability requirements.

  6. Synchrotron X-ray scattering studies of nanostructure-formation at interfaces

    NASA Astrophysics Data System (ADS)

    Sanyal, Milan K.

    2013-02-01

    We shall discuss results of a series of synchrotron x-ray scattering studies to understand the ordering of nanostructured materials formed at interfaces. In particular we shall discuss formation of germanium quantum-dots at the MBE grown silicon-germanium super-lattice structure and reversible crystallization of monolayer of Polyhedral Oligomeric SilSesquioxane (POSS) on water surface. The consistent analysis of the x-ray reflectivity and diffraction data collected in the Indian Beamline at Photon Factory Synchrotron, KEK, Japan have allowed determination of electron density and strain profile as a function of depth. The electron density profile obtained from the reflectivity and elemental profile obtained from SIMS measurements were effectively used to calculate diffraction data that provided strain and compositional profiles. The behaviour of amphiphilic Silsesquioxane POSS molecules under in-plane pressure in a Langmuir trough was studied at the ChemMatCARS, Sector 15, Advanced Photon Source, USA. We observe clear evidence of reversible crystallization of the POSS monolayers at the air-water interface - at higher pressure sharp diffraction spots are observed and as the pressure is withdrawn typical monolayer scattering comes back. Results of AFM studies of the lifted films in these two extreme phases were found to be consistent with the x-ray data.

  7. The energy spectrum of anomalous X-ray pulsars and soft gamma-ray repeaters

    NASA Astrophysics Data System (ADS)

    Trümper, J. E.; Zezas, A.; Ertan, Ü.; Kylafis, N. D.

    2010-07-01

    Context. Anomalous X-ray pulsars (AXPs) and soft gamma-ray repeaters (SGRs) exhibit characteristic X-ray luminosities (both soft and hard) of around 1035 erg s-1 and characteristic power-law, hard X-ray spectra extending to about 200 keV. Two AXPs also exhibit pulsed radio emission. Aims: Assuming that AXPs and SGRs accrete matter from a fallback disk, we attempt to explain both the soft and the hard X-ray emission as the result of the accretion process. We also attempt to explain their radio emission or the lack of it. Methods: We test the hypothesis that the power-law, hard X-ray spectra are produced in the accretion flow mainly by bulk-motion Comptonization of soft photons emitted at the neutron star surface. Fallback disk models invoke surface dipole magnetic fields of 1012 - 1013 G, which is what we assume here. Results: Unlike normal X-ray pulsars, for which the accretion rate is highly super-Eddington, the accretion rate is approximately Eddington in AXPs and SGRs and thus the bulk-motion Comptonization operates efficiently. As an illustrative example we reproduce both the hard and the soft X-ray spectra of AXP 4U 0142+61 well using the XSPEC package compTB. Conclusions: Our model seems to explain both the hard and the soft X-ray spectra of AXPs and SGRs, as well as their radio emission or the lack of it, in a natural way. It might also explain the short bursts observed in these sources. On the other hand, it cannot explain the giant X-ray outbursts observed in SGRs, which may result from the conversion of magnetic energy in local multipole fields.

  8. Synchrotron X-ray Powder Diffraction and Absorption Spectroscopy in Pulsed Magnetic Fields with Milliseconds Duration

    NASA Astrophysics Data System (ADS)

    Vanacken, J.; Detlefs, C.; Mathon, O.; Frings, P.; Duc, F.; Lorenzo, J. E.; Nardone, M.; Billette, J.; Zitouni, A.; Dominguez, M.-C.; Herczeg, J.; Bras, W.; Moshchalkov, V. V.; Rikken, G.

    2007-03-01

    X-ray Powder Diffraction and X-ray Absorption Spectroscopy experiments (WAS) and X-ray magnetic circular dichroism (XMCD) experiments were carried out at the ESRF DUBBLE beam line (BM26) and at the energy dispersive beam line (ID24), respectively. A mobile pulse generator, developed at the LNCMP, delivered 110kJ to the load coil, which was sufficient to generate peak fields of 30T with a rise time of about 5 ms. A liquid He flow cryostat allowed us to vary the sample temperature accurately between 4.2K and 300K. Powder diffraction patterns of TbVO4 were recorded in a broad temperature range using 21 keV monochromatic X-rays and using an on-line image plate detector. We observed the suppression of the Jahn-Teller structural distortion in TbVO4 due to the high magnetic pulsed field. XAS spectra could be measured and finite XMCD signals, directly proportional to the magnetic moment on the Gd absorber atom, were measured in thin Gd foils. Thanks to its element and orbital selectivity, XMCD proofs to be very useful in probing the magnetic properties and due to the strong brilliance of the synchrotron beam, the signals can be measured even in the ms range.

  9. Synthesis of nanoparticles through x-ray radiolysis using synchrotron radiation

    NASA Astrophysics Data System (ADS)

    Yamaguchi, A.; Okada, I.; Fukuoka, T.; Ishihara, M.; Sakurai, I.; Utsumi, Y.

    2016-09-01

    The synthesis and deposition of nanoparticles consisting of Cu and Au in a CuSO4 solution with some kinds of alcohol and electroplating solution containing gold (I) trisodium disulphite under synchrotron X-ray radiation was investigated. The functional group of alcohol plays an important in nucleation, growth and aggregation process of copper and cupric oxide particles. We found that the laboratory X-ray source also enables us to synthesize the NPs from the metallic solution. As increasing X-ray exposure time, the full length at half width of particle size distribution is broader and higher-order nanostructure containing NPs clusters is formed. The surface-enhanced Raman scattering (SERS) of 4, 4'-bipyridine (4bpy) in aqueous solution was measured using higher-order nanostructure immobilized on silicon substrates under systematically-varied X-ray exposure. This demonstration provide a clue to develop a three-dimensional printing and sensor for environmental analyses and molecular detection through simple SERS measurements.

  10. Workshops on Science Enabled by a Coherent, CW, Synchrotron X-ray Source, June 2011

    SciTech Connect

    Brock, Joel

    2012-01-03

    In June of 2011 we held six two-day workshops called "XDL-2011: Science at the Hard X-ray Diffraction Limit". The six workshops covered (1) Diffraction-based imaging techniques, (2) Biomolecular structure from non-crystalline materials, (3) Ultra-fast science, (4) High-pressure science, (5) Materials research with nano-beams and (6) X-ray photon correlation spectroscopy (XPCS), In each workshop, invited speaker from around the world presented examples of novel experiments that require a CW, diffraction-limited source. During the workshop, each invited speaker provided a one-page description of the experiment and an illustrative graphic. The experiments identified by the workshops demonstrate the broad and deep scientific case for a CW coherent synchrotron x-ray source. The next step is to perform detailed simulations of the best of these ideas to test them quantitatively and to guide detailed x-ray beam-line designs. These designs are the first step toward developing detailed facility designs and cost estimates.

  11. A new approach to synchrotron energy-dispersive X-ray diffraction computed tomography.

    PubMed

    Lazzari, Olivier; Egan, Christopher K; Jacques, Simon D M; Sochi, Taha; Di Michiel, Marco; Cernik, Robert J; Barnes, Paul

    2012-07-01

    A new data collection strategy for performing synchrotron energy-dispersive X-ray diffraction computed tomography has been devised. This method is analogous to angle-dispersive X-ray diffraction whose diffraction signal originates from a line formed by intersection of the incident X-ray beam and the sample. Energy resolution is preserved by using a collimator which defines a small sampling voxel. This voxel is translated in a series of parallel straight lines covering the whole sample and the operation is repeated at different rotation angles, thus generating one diffraction pattern per translation and rotation step. The method has been tested by imaging a specially designed phantom object, devised to be a demanding validator for X-ray diffraction imaging. The relative strengths and weaknesses of the method have been analysed with respect to the classic angle-dispersive technique. The reconstruction accuracy of the method is good, although an absorption correction is required for lower energy diffraction because of the large path lengths involved. The spatial resolution is only limited to the width of the scanning beam owing to the novel collection strategy. The current temporal resolution is poor, with a scan taking several hours. The method is best suited to studying large objects (e.g. for engineering and materials science applications) because it does not suffer from diffraction peak broadening effects irrespective of the sample size, in contrast to the angle-dispersive case.

  12. A hard X-ray view of the soft excess in AGN

    NASA Astrophysics Data System (ADS)

    Boissay, Rozenn; Ricci, Claudio; Paltani, Stéphane

    2016-04-01

    An excess of X-ray emission below 1 keV, called soft excess, is detected in a large fraction of Seyfert 1-1.5s. The origin of this feature remains debated, as several models have been suggested to explain it, including warm Comptonization and blurred ionized reflection. In order to constrain the origin of this component, we exploit the different behaviors of these models above 10 keV. Ionized reflection covers a broad energy range, from the soft X-rays to the hard X-rays, while Comptonization drops very quickly in the soft X-rays. We present here the results of a study done on 102 Seyfert 1s (Sy 1.0, 1.2, 1.5 and NLSy1) from the Swift BAT 70-Month Hard X-ray Survey catalog. The joint spectral analysis of Swift/BAT and XMM-Newton data allows a hard X-ray view of the soft excess that is present in about 80% of the objects of our sample. We discuss how the soft-excess strength is linked to the reflection at high energy, to the photon index of the primary continuum and to the Eddington ratio. In particular, we find a positive dependence of the soft excess intensity on the Eddington ratio. We compare our results to simulations of blurred ionized-reflection models and show that they are in contradiction. By stacking both XMM-Newton and Swift/BAT spectra per soft-excess strength, we see that the shape of reflection at hard X-rays stays constant when the soft excess varies, showing an absence of link between reflection and soft excess. We conclude that the ionized-reflection model as the origin of the soft excess is disadvantaged in favor of the warm Comptonization model in our sample of Seyfert 1s.

  13. Electronic Structures of Uranium Compounds Studied by Soft X-ray Photoelectron Spectroscopy

    NASA Astrophysics Data System (ADS)

    Fujimori, Shin-ichi; Takeda, Yukiharu; Okane, Tetsuo; Saitoh, Yuji; Fujimori, Atsushi; Yamagami, Hiroshi; Haga, Yoshinori; Yamamoto, Etsuji; Ōnuki, Yoshichika

    2016-06-01

    The electronic structures of uranium-based compounds have been studied by photoelectron spectroscopy with soft X-ray synchrotron radiation. Angle-resolved photoelectron spectroscopy with soft X-rays has made it possible to directly observe their bulk band structures and Fermi surfaces. It has been shown that the band structures and Fermi surfaces of itinerant compounds such as UB2, UN, and UFeGa5 are quantitatively described by a band-structure calculation treating all U 5f electrons as itinerant. Furthermore, the overall electronic structures of heavy-fermion compounds such as UPd2Al3, UNi2Al3, and URu2Si2 are also explained by a band-structure calculation, although some disagreements exist, which might originate from the electron correlation effect. This suggests that the itinerant description of U 5f states is an appropriate starting point for the description of their electronic structures. The situation is similar for ferromagnetic superconductors such as UGe2, URhGe, UCoGe, and UIr, although the complications from their low-symmetry crystal structures make it more difficult to describe their detailed electronic structures. The local electronic structures of the uranium site have been probed by core-level photoelectron spectroscopy with soft X-rays. The comparisons of core-level spectra of heavy-fermion compounds with typical itinerant and localized compounds suggest that the local electronic structures of most itinerant and heavy-fermion compounds are close to the U 5f3 configuration except for UPd2Al3 and UPt3. The core-level spectrum of UPd2Al3 has similarities to those of both itinerant and localized compounds, suggesting that it is located at the boundary between the itinerant and localized states. Moreover, the spectrum of UPt3 is very close to that of the localized compound UPd3, suggesting that it is nearly localized, although there are narrow quasi-particle bands in the vicinity of EF.

  14. [Experimental investigation of laser plasma soft X-ray source with gas target].

    PubMed

    Ni, Qi-liang; Gong, Yan; Lin, Jing-quan; Chen, Bo; Cao, Jian-lin

    2003-02-01

    This paper describes a debris-free laser plasma soft X-ray source with a gas target, which has high operating frequency and can produce strong soft X-ray radiation. The valve of this light source is drived by a piezoelectrical ceramic whose operating frequency is up to 400 Hz. In comparison with laser plasma soft X-ray sources using metal target, the light source is debris-free. And it has higher operating frequency than gas target soft X-ray sources whose nozzle is controlled by a solenoid valve. A channel electron multiplier (CEM) operating in analog mode is used to detect the soft X-ray generated by the laser plasma source, and the CEM's output is fed to to a charge-sensitive preamplifier for further amplification purpose. Output charges from the CEM are proportional to the amplitude of the preamplifier's output voltage. Spectra of CO2, Xe and Kr at 8-14 nm wavelength which can be used for soft X-ray projection lithography are measured. The spectrum for CO2 consists of separate spectral lines originate mainly from the transitions in Li-like and Be-like ions. The Xe spectrum originating mainly from 4d-5f, 4d-4f, 4d-6p and 4d-5p transitions in multiply charged xenon ions. The spectrum for Kr consists of separate spectral lines and continuous broad spectra originating mainly from the transitions in Cu-, Ni-, Co- and Fe-like ions.

  15. Ground Laboratory Soft X-Ray Durability Evaluation of Aluminized Teflon FEP Thermal Control Insulation

    NASA Technical Reports Server (NTRS)

    Banks, Bruce A.; deGroh, Kim K.; Stueber, Thomas J.; Sechkar, Edward A.

    1998-01-01

    Metallized Teflon fluorinated ethylene propylene (FEP) thermal control insulation is mechanically degraded if exposed to a sufficient fluence of soft x-ray radiation. Soft x-ray photons (4-8 A in wavelength or 1.55 - 3.2 keV) emitted during solar flares have been proposed as a cause of mechanical properties degradation of aluminized Teflon FEP thermal control insulation on the Hubble Space Telescope (HST). Such degradation can be characterized by a reduction in elongation-to-failure of the Teflon FER Ground laboratory soft x-ray exposure tests of aluminized Teflon FEP were conducted to assess the degree of elongation degradation which would occur as a result of exposure to soft x-rays in the range of 3-10 keV. Tests results indicate that soft x-ray exposure in the 3-10 keV range, at mission fluence levels, does not alone cause the observed reduction in elongation of flight retrieved samples. The soft x-ray exposure facility design, mechanical properties degradation results and implications will be presented.

  16. A table-top femtosecond time-resolved soft x-ray transient absorption spectrometer

    SciTech Connect

    Leone, Stephen; Loh, Zhi-Heng; Khalil, Munira; Correa, Raoul E.; Leone, Stephen R.

    2008-05-21

    A laser-based, table-top instrument is constructed to perform femtosecond soft x-ray transient absorption spectroscopy. Ultrashort soft x-ray pulses produced via high-order harmonic generation of the amplified output of a femtosecond Ti:sapphire laser system are used to probe atomic core-level transient absorptions in atoms and molecules. The results provide chemically specific, time-resolved dynamics with sub-50-fs time resolution. In this setup, high-order harmonics generated in a Ne-filled capillary waveguide are refocused by a gold-coated toroidal mirror into the sample gas cell, where the soft x-ray light intersects with an optical pump pulse. The transmitted high-order harmonics are spectrally dispersed with a home-built soft x-ray spectrometer, which consists of a gold-coated toroidal mirror, a uniform-line spaced plane grating, and a soft x-ray CCD camera. The optical layout of the instrument, design of the soft x-ray spectrometer, and spatial and temporal characterization of the high-order harmonics are described. Examples of static and time-resolved photoabsorption spectra collected on this apparatus are presented.

  17. Lensless diffractive imaging using tabletop coherent high-harmonic soft-X-ray beams.

    PubMed

    Sandberg, Richard L; Paul, Ariel; Raymondson, Daisy A; Hädrich, Steffen; Gaudiosi, David M; Holtsnider, Jim; Tobey, Ra'anan I; Cohen, Oren; Murnane, Margaret M; Kapteyn, Henry C; Song, Changyong; Miao, Jianwei; Liu, Yanwei; Salmassi, Farhad

    2007-08-31

    We present the first experimental demonstration of lensless diffractive imaging using coherent soft x rays generated by a tabletop soft-x-ray source. A 29 nm high harmonic beam illuminates an object, and the subsequent diffraction is collected on an x-ray CCD camera. High dynamic range diffraction patterns are obtained by taking multiple exposures while blocking small-angle diffraction using beam blocks of varying size. These patterns reconstruct to images with 214 nm resolution. This work demonstrates a practical tabletop lensless microscope that promises to find applications in materials science, nanoscience, and biology.

  18. The Soft X-ray Telescope for Solar-A - Design evolution and lessons learned

    NASA Technical Reports Server (NTRS)

    Bruner, Marilyn E.

    1992-01-01

    The Japanese Solar-A satellite mission's Soft X-ray Telescope uses grazing-incidence optics, a CCD detector, and a pair of filter wheels for wavelength selection. A coaxially-mounted visible-light lens furnished sunspot and magnetic plage images, together with aspect information which aids in aligning the soft X-ray images with those from the satellite's Hard X-ray Telescope. Instrument electronics are microprocessor-based, and imbedded in a tightly integrated distributed system. Control software is divided between the instrument microprocessor and the spacecraft control computer.

  19. Progress in compact soft x-ray lasers and their applications

    SciTech Connect

    Suckewer, S.; Skinner, C.H.

    1995-01-01

    The ultra-high brightness and short pulse duration of soft x-ray lasers provide unique advantages for novel applications. A crucial factor in the availability of these devices is their scale and cost. Recent breakthroughs in this field has brought closer the advent of table-top devices, suitable for applications to fields such as x-ray microscopy, chemistry, material science, plasma diagnostics, and lithography. In this article we review recent progress in the development of compact (table-top) soft x-ray lasers.

  20. The GALAXIES beamline at the SOLEIL synchrotron: inelastic X-ray scattering and photoelectron spectroscopy in the hard X-ray range.

    PubMed

    Rueff, J P; Ablett, J M; Céolin, D; Prieur, D; Moreno, Th; Balédent, V; Lassalle-Kaiser, B; Rault, J E; Simon, M; Shukla, A

    2015-01-01

    The GALAXIES beamline at the SOLEIL synchrotron is dedicated to inelastic X-ray scattering (IXS) and photoelectron spectroscopy (HAXPES) in the 2.3-12 keV hard X-ray range. These two techniques offer powerful complementary methods of characterization of materials with bulk sensitivity, chemical and orbital selectivity, resonant enhancement and high resolving power. After a description of the beamline components and endstations, the beamline capabilities are demonstrated through a selection of recent works both in the solid and gas phases and using either IXS or HAXPES approaches. Prospects for studies on liquids are discussed.

  1. Simultaneous, single-pulse, synchrotron x-ray imaging and diffraction under gas gun loading

    SciTech Connect

    Fan, D.; Huang, J. W.; Zeng, X. L.; Li, Y.; E, J. C.; Huang, J. Y.; Sun, T.; Fezzaa, K.; Wang, Z.; Luo, S. N.

    2016-05-23

    We develop a mini gas gun system for simultaneous, single-pulse, x-ray diffraction and imaging under high strain-rate loading at the beamline 32-ID of the Advanced Photon Source. In order to increase the reciprocal space covered by a small-area detector, a conventional target chamber is split into two chambers: a narrowed measurement chamber and a relief chamber. The gas gun impact is synchronized with synchrotron x-ray pulses and high-speed cameras. Depending on a camera’s capability, multiframe imaging and diffraction can be achieved. The proof-of-principle experiments are performed on single-crystal sapphire. The diffraction spots and images during impact are analyzed to quantify lattice deformation and fracture; diffraction peak broadening is largely caused by fracture-induced strain inhomogeneity. Finally, our results demonstrate the potential of such multiscale measurements for revealing and understanding high strain-rate phenomena at dynamic extremes.

  2. High-energy synchrotron x-ray techniques for studying irradiated materials

    DOE PAGES

    Park, Jun-Sang; Zhang, Xuan; Sharma, Hemant; ...

    2015-03-20

    High performance materials that can withstand radiation, heat, multiaxial stresses, and corrosive environment are necessary for the deployment of advanced nuclear energy systems. Nondestructive in situ experimental techniques utilizing high energy x-rays from synchrotron sources can be an attractive set of tools for engineers and scientists to investigate the structure–processing–property relationship systematically at smaller length scales and help build better material models. In this paper, two unique and interconnected experimental techniques, namely, simultaneous small-angle/wide-angle x-ray scattering (SAXS/WAXS) and far-field high-energy diffraction microscopy (FF-HEDM) are presented. Finally, the changes in material state as Fe-based alloys are heated to high temperatures ormore » subject to irradiation are examined using these techniques.« less

  3. Single-crystal sapphire microstructure for high-resolution synchrotron X-ray monochromators

    SciTech Connect

    Asadchikov, Victor E.; Butashin, Andrey V.; Buzmakov, Alexey V.; Deryabin, Alexander N.; Kanevsky, Vladimir M.; Prokhorov, Igor A.; Roshchin, Boris S.; Volkov, Yuri O.; Zolotov, Dennis A.; Jafari, Atefeh; Alexeev, Pavel; Cecilia, Angelica; Baumbach, Tilo; Bessas, Dimitrios; Danilewsky, Andreas N.; Sergueev, Ilya; Wille, Hans -Christian; Hermann, Raphael P.

    2016-03-22

    We report on the growth and characterization of several sapphire single crystals for the purpose of x-ray optics applications. Structural defects were studied by means of laboratory double-crystal X-ray diffractometry and white beam synchrotron-radiation topography. The investigations confirmed that the main defect types are dislocations. The best quality crystal was grown using the Kyropoulos technique with a dislocation density of 102-103 cm-2 and a small area with approximately 2*2 mm2 did not show dislocation contrast in many reflections and has suitable quality for application as a backscattering monochromator. As a result, a clear correlation between growth rate and dislocation density is observed, though growth rate is not the only parameter impacting the quality.

  4. Synchrotron hard X-ray imaging of shock-compressed metal powders

    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 poster will present the application of a new, high-energy (50 to 250 keV) synchrotron X-ray radiography technique to the study of shock-compressed granular materials. Following plate-impact loading, transmission radiography was used to quantitatively observe the compaction and release processes in a range of high-Z metal powders (e.g. Fe, Ni, Cu). By comparing the predictions of 3D numerical models initialized from X-ray tomograms-captured prior to loading-with experimental results, this research represents a new approach to refining mesoscopic compaction models. The authors gratefully acknowledge the ongoing support of Imperial College London, EPSRC, STFC and the Diamond Light Source, and AWE Plc.

  5. High-Resolution X-Ray Scattering Topography Using Synchrotron Radiation Microbeam

    NASA Astrophysics Data System (ADS)

    Chikaura, Yoshinori; Suzuki, Yoshifumi; Kii, Hideki

    1994-02-01

    Although spatial resolution is the most essential factor determining the function of X-ray topography, it has not been improved in 30 years in spite of increasing requirements for highly-resolvable topography in materials science. X-ray scattering topography using a microbeam is a method capable of overcoming this resolution problem. Because the maximum resolution of an apparatus using a sealed-off tube is limited to 20 µ m, we designed and constructed scattering topography equipment using a synchrotron radiation microbeam. In the experiment, the slit system forms the microbeam 7 µ m in diameter. We observed a cellulose distribution in bamboo as a testing material. When the scanning step was 2 µ m, we attained spatial resolution less than 5 µ m.

  6. Source assemblage types for cratonic diamonds from X-ray synchrotron diffraction

    NASA Astrophysics Data System (ADS)

    Nestola, F.; Alvaro, M.; Casati, M. N.; Wilhelm, H.; Kleppe, A. K.; Jephcoat, A. P.; Domeneghetti, M. C.; Harris, J. W.

    2016-11-01

    Three single crystals of clinopyroxene trapped within three different gem-quality diamonds from the Udachnaya kimberlite (Siberia, Russia) were analysed in situ by single-crystal synchrotron X-ray diffraction in order to obtain information on their chemical composition and infer source assemblage type. A non-destructive approach was used with high-energy (≈ 60 keV; λ ≈ 0.206 Å) at I15, the extreme-conditions beamline at Diamond Light Source. A dedicated protocol was used to center the mineral inclusions located deep inside the diamonds in the X-ray beam. Our results reveal that two of the inclusions can be associated with peridotitic paragenesis whereas the third is eclogitic. This study also demonstrates that this non-destructive experimental approach is extremely efficient in evaluating the origin of minerals trapped in their diamond hosts.

  7. Elemental characterisation of melanin in feathers via synchrotron X-ray imaging and absorption spectroscopy

    PubMed Central

    Edwards, Nicholas P.; van Veelen, Arjen; Anné, Jennifer; Manning, Phillip L.; Bergmann, Uwe; Sellers, William I.; Egerton, Victoria M.; Sokaras, Dimosthenis; Alonso-Mori, Roberto; Wakamatsu, Kazumasa; Ito, Shosuke; Wogelius, Roy A.

    2016-01-01

    Melanin is a critical component of biological systems, but the exact chemistry of melanin is still imprecisely known. This is partly due to melanin’s complex heterogeneous nature and partly because many studies use synthetic analogues and/or pigments extracted from their natural biological setting, which may display important differences from endogenous pigments. Here we demonstrate how synchrotron X-ray analyses can non-destructively characterise the elements associated with melanin pigment in situ within extant feathers. Elemental imaging shows that the distributions of Ca, Cu and Zn are almost exclusively controlled by melanin pigment distribution. X-ray absorption spectroscopy demonstrates that the atomic coordination of zinc and sulfur is different within eumelanised regions compared to pheomelanised regions. This not only impacts our fundamental understanding of pigmentation in extant organisms but also provides a significant contribution to the evidence-based colour palette available for reconstructing the appearance of fossil organisms. PMID:27658854

  8. Elemental characterisation of melanin in feathers via synchrotron X-ray imaging and absorption spectroscopy

    NASA Astrophysics Data System (ADS)

    Edwards, Nicholas P.; van Veelen, Arjen; Anné, Jennifer; Manning, Phillip L.; Bergmann, Uwe; Sellers, William I.; Egerton, Victoria M.; Sokaras, Dimosthenis; Alonso-Mori, Roberto; Wakamatsu, Kazumasa; Ito, Shosuke; Wogelius, Roy A.

    2016-09-01

    Melanin is a critical component of biological systems, but the exact chemistry of melanin is still imprecisely known. This is partly due to melanin’s complex heterogeneous nature and partly because many studies use synthetic analogues and/or pigments extracted from their natural biological setting, which may display important differences from endogenous pigments. Here we demonstrate how synchrotron X-ray analyses can non-destructively characterise the elements associated with melanin pigment in situ within extant feathers. Elemental imaging shows that the distributions of Ca, Cu and Zn are almost exclusively controlled by melanin pigment distribution. X-ray absorption spectroscopy demonstrates that the atomic coordination of zinc and sulfur is different within eumelanised regions compared to pheomelanised regions. This not only impacts our fundamental understanding of pigmentation in extant organisms but also provides a significant contribution to the evidence-based colour palette available for reconstructing the appearance of fossil organisms.

  9. Silicon loss metrology using synchrotron x-ray reflectance and Bragg diffraction

    SciTech Connect

    Bhargava, Mansi; Wolfe, John C.; Donner, Wolfgang; Srivastava, Aseem

    2007-09-26

    We use synchrotron x-ray reflectometry and Bragg diffraction to study silicon loss in the low temperature plasma oxidation of silicon-on-insulator (SOI) wafers. We show that Laue oscillations associated with the Si (004) Bragg peak give the number of Si (004) planes in the device layer to within an experimental error of 0.07 nm and that X-ray reflectometry gives the total thickness of the device layer and the surface oxide to within 0.05 nm. We find that silicon loss in samples processed in two different plasma systems correspond to an increase in total thickness that is consistent with the formation of SiO{sub 2}.

  10. X-ray harmonics rejection on third-generation synchrotron sources using compound refractive lenses.

    PubMed

    Polikarpov, Maxim; Snigireva, Irina; Snigirev, Anatoly

    2014-05-01

    A new method of harmonics rejection based on X-ray refractive optics has been proposed. Taking into account the fact that the focal distance of the refractive lens is energy-dependent, the use of an off-axis illumination of the lens immediately leads to spatial separation of the energy spectrum by focusing the fundamental harmonic at the focal point and suppressing the unfocused high-energy radiation with a screen absorber or slit. The experiment was performed at the ESRF ID06 beamline in the in-line geometry using an X-ray transfocator with compound refractive lenses. Using this technique the presence of the third harmonic has been reduced to 10(-3). In total, our method enabled suppression of all higher-order harmonics to five orders of magnitude using monochromator detuning. The method is well suited to third-generation synchrotron radiation sources and is very promising for the future ultimate storage rings.

  11. Single-crystal sapphire microstructure for high-resolution synchrotron X-ray monochromators

    DOE PAGES

    Asadchikov, Victor E.; Butashin, Andrey V.; Buzmakov, Alexey V.; ...

    2016-03-22

    We report on the growth and characterization of several sapphire single crystals for the purpose of x-ray optics applications. Structural defects were studied by means of laboratory double-crystal X-ray diffractometry and white beam synchrotron-radiation topography. The investigations confirmed that the main defect types are dislocations. The best quality crystal was grown using the Kyropoulos technique with a dislocation density of 102-103 cm-2 and a small area with approximately 2*2 mm2 did not show dislocation contrast in many reflections and has suitable quality for application as a backscattering monochromator. As a result, a clear correlation between growth rate and dislocation densitymore » is observed, though growth rate is not the only parameter impacting the quality.« less

  12. High-energy synchrotron x-ray techniques for studying irradiated materials

    SciTech Connect

    Park, Jun-Sang; Zhang, Xuan; Sharma, Hemant; Kenesei, Peter; Hoelzer, David; Li, Meimei; Almer, Jonathan

    2015-03-20

    High performance materials that can withstand radiation, heat, multiaxial stresses, and corrosive environment are necessary for the deployment of advanced nuclear energy systems. Nondestructive in situ experimental techniques utilizing high energy x-rays from synchrotron sources can be an attractive set of tools for engineers and scientists to investigate the structure–processing–property relationship systematically at smaller length scales and help build better material models. In this paper, two unique and interconnected experimental techniques, namely, simultaneous small-angle/wide-angle x-ray scattering (SAXS/WAXS) and far-field high-energy diffraction microscopy (FF-HEDM) are presented. Finally, the changes in material state as Fe-based alloys are heated to high temperatures or subject to irradiation are examined using these techniques.

  13. Pathway of a damaging mechanism - Analyzing chloride attack by synchrotron based X-ray diffraction

    NASA Astrophysics Data System (ADS)

    Schlegel, M. C.; Stroh, J.; Malaga, K.; Meng, B.; Panne, U.; Emmerling, F.

    2015-06-01

    Typically, the changes of the phase compositions due to the chemical attack are studied in-situ only by chemical analysis or microscopy. In this study, the chloride transport and binding in the cement matrix in different cementitious materials was analyzed by synchrotron based X-ray diffraction (SyXRD) and energy dispersive X-ray spectroscopy (EDX). Sample materials consisting of cement paste were embedded in high concentrated sodium chloride solution over different time spans. Afterwards, the phase and chemical compositions were determined. The high spatial resolution and the information about the chloride distribution offer a detailed view of chloride binding in the cement matrix and allow the conclusions about the degradation mechanisms. The results are discussed related to the influence of different supplementary cementitious materials on the damaging mechanism.

  14. Single and double grating-based X-ray microtomography using synchrotron radiation

    NASA Astrophysics Data System (ADS)

    Thalmann, P.; Bikis, C.; Hipp, A.; Müller, B.; Hieber, S. E.; Schulz, G.

    2017-02-01

    Hard X-ray phase contrast imaging techniques have become most suitable for the non-destructive three-dimensional visualization of soft tissues at the microscopic level. Among the hard X-ray grating interferometry methods, a single-grating approach (XSGI) has been implemented by simplifying the established double-grating interferometer (XDGI). We quantitatively compare the XSGI and XDGI tomograms of a human nerve and demonstrate that both techniques provide sufficient contrast to allow for the distinction of tissue types. The two-fold binned data show spatial resolution of (5.2 ± 0.6) μm and (10.7 ± 0.6) μm, respectively, underlying the performance of XSGI in soft tissue imaging.

  15. Reflectivity around the gold L-edges of x-ray reflector of the soft x-ray telescope onboard ASTRO-H

    NASA Astrophysics Data System (ADS)

    Maeda, Yoshitomo; Kikuchi, Naomichi; Kurashima, Sho; Ishida, Manabu; Iizuka, Ryo; Hayashi, Takayuki; Okajima, Takashi; Matsumoto, Hironori; Mitsuishi, Ikuyuki; Saji, Shigetaka; Sato, Toshiki; Tachibana, Sasagu; Mori, Hideyuki; Christensen, Finn; Brejnholt, Nicolai; Nitta, Kiyofumi; Uruga, Tomoya

    2016-07-01

    We report the atomic scattering factor in the 11.2{15.4 keV for the ASTRO-H Soft X-ray Telescope (SXT)9 obtained in the ground based measurements. The large effective area of the SXT covers above 10 keV. In fact, the flight data show the spectra of the celestical objects in the hard X-ray band. In order to model the area, the reflectivity measurements in the 11.2{15.4 keV band with the energy pitch of 0.4 { 0.7 eV were made in the synchrotron beamline Spring-8 BL01B1. We obtained atomic scattering factors f1 and f2 by the curve fitting to the reflectivities of our witness sample. The edges associated with the gold's L-I, II, and III transitions are identified, of which the depths are found to be roughly 60% shallower than those expected from the Henke's atomic scattering factor.

  16. Prospects for compact high-intensity laser synchrotron x-ray and gamma sources

    SciTech Connect

    Pogorelsky, I.V.

    1996-11-01

    A laser interacting with a relativistic electron beam behaves like a virtual wiggler of an extremely short period equal to half of the laser wavelength. This approach opens a route to relatively compact, high-brightness x-ray sources alternative or complementary to conventional synchrotron light sources. Although not new, the laser synchrotron source (LSS) concept is still waiting for a convincing demonstration. Available at the BNL Accelerator Test Facility (ATF), a high-brightness electron beam and the high-power CO{sub 2} laser may be used as prototype LSS brick stones. In a feasible demonstration experiment, 10-GW, 100-ps CO{sub 2} laser beam will be brought to a head-on collision with a 10-ps, 0.5-nC, 50 MeV electron bunch. Flashes of collimated 4.7 keV (2.6 {angstrom}) x-rays of 10-ps pulse duration, with a flux of {approximately} 10{sup 19} photons/sec, will be produced via linear Compton backscattering. The x-ray spectrum is tunable proportionally to the e-beam energy. A rational short-term extension of the proposed experiment would be further enhancement of the x-ray flux to the 10{sup 22} photons/sec level, after the ongoing ATF CO{sub 2} laser upgrade to 5 TW peak power and electron bunch shortening to 3 ps is realized. In the future, exploiting the promising approach of a high-gradient laser wake field accelerator, a compact ``table-top`` LSS of monochromatic gamma radiation may become feasible.

  17. Prospects for compact high-intensity laser synchrotron x-ray and gamma sources

    SciTech Connect

    Pogorelsky, I.V.

    1997-01-01

    A laser interacting with a relativistic electron beam behaves like a virtual wiggler of an extremely short period equal to half of the laser wavelength. This approach opens a route to relatively compact, high- brightness x-ray sources alternative or complementary to conventional synchrotron light sources. Although not new, the laser synchrotron source (LSS) concept is still waiting for a convincing demonstration. Available at the BNL Accelerator Test Facility (ATF), a high- brightness electron beam and the high-power C0{sub 2} laser may be used as prototype LSS brick stones. In a feasible demonstration experiment, 10 GW, 100 ps C0{sub 2} laser beam will be brought to a head-on collision with a 10 ps, 0.5 nC, 50 MeV electron bunch. Flashes of collimated 4.7 keV (2.6 A) x-rays of 10-ps pulse duration, with a flux of {approximately}10{sup 19} photons/sec, will be produced via linear Compton backscattering. The x-ray spectra is tunable proportionally to the e- beam energy. A rational short-term extension of the proposed experiment would be further enhancement of the x-ray flux to the 10{sup 22} photon/sec level, after the ongoing ATF C0{sub 2} laser upgrade to 5 TW peak power and electron bunch shortening to 3 ps is realized. In the future, exploiting the promising approach of a high-gradient laser wake field accelerator, a compact ``table- top`` LSS of monochromatic gamma radiation may become feasible.

  18. Prospects for compact high-intensity laser synchrotron x-ray and gamma sources

    NASA Astrophysics Data System (ADS)

    Pogorelsky, I. V.

    1997-03-01

    A laser interacting with a relativistic electron beam behaves like a virtual wiggler of an extremely short period equal to half of the laser wavelength. This approach opens a route to relatively compact, high-brightness x-ray sources alternative or complementary to conventional synchrotron light sources. Although not new, the laser synchrotron source (LSS) concept is still waiting for a convincing demonstration. Available at the BNL Accelerator Test Facility (ATF), a high-brightness electron beam and the high-power CO2 laser may be used for prototype LSS demonstration. In a feasible demonstration experiment, 10-GW, 100-ps CO2 laser beam will be brought to a head-on collision with a 10-ps, 0.5-nC, 50 MeV electron bunch. Flashes of collimated 4.7 keV (2.6 Å) x-rays of 10-ps pulse duration, with a flux of ˜1019photons/sec, will be produced via linear Compton backscattering. The x-ray spectrum is tunable proportionally to the e-beam energy. A rational short-term extension of the proposed experiment would be further enhancement of the x-ray flux to the 1022 photons/sec level, after the ongoing ATF CO2 laser upgrade to 5 TW peak power and electron bunch shortening to 3 ps is realized. In the future, exploiting the promising approach of a high-gradient laser wake field accelerator, a compact "table-top" LSS of monochromatic gamma radiation may become feasible.

  19. CCD-based detector for protein crystallography with synchrotron X-rays

    NASA Astrophysics Data System (ADS)

    Strauss, M. G.; Westbrook, E. M.; Naday, I.; Coleman, T. A.; Westbrook, M. L.; Travis, D. J.; Sweet, R. M.; Pflugrath, J. W.; Stanton, M.

    1990-11-01

    A detector with a 114 mm aperture, based on a charge-coupled device (CCD), has been designed for X-ray diffraction studies in protein crystallography. The detector was tested at the National Synchrotron Light Source with a beam intensity, through a 0.3 mm collimator, of greater than 109 X-ray photons/s. A fiberoptic taper, an image intensifier, and a lens demagnify, intensify, and focus the image onto a CCD having 512×512 pixels. The statistical uncertainty in the detector output was evaluated as a function of conversion gain. From this, a detective quantum efficiency (DQE) of 0.36 was derived. The dynamic range of a 4×4 pixel resolution element, comparable in size to a diffraction peak, was 104. The point-spread function shows FWHM resolution of approximately 1 pixel, where a pixel is 160 μm on the detector face. A data set collected from a chicken egg-white lysozyme crystal, consisting of 495 0.1° frames, was processed by the MADNES data reduction program. The symmetry R-factors for the data were 3.2-3.5%. In a separate experiment a complete lysozyme data set consisting of 45 1° frames was obtained in just 36 s of X-ray exposure. Diffraction images from crystals of the myosin S1 head (a = 275 Å) were also recorded; the Bragg spots, only 5 pixels apart, were separated but not fully resolved. Changes in the detector design that will improve the DQE and spatial resolution are outlined. The overall performance showed that this type of detector is well suited for X-ray scattering investigations with synchrotron sources.

  20. Experimental comparison between speckle and grating-based imaging technique using synchrotron radiation X-rays.

    PubMed

    Kashyap, Yogesh; Wang, Hongchang; Sawhney, Kawal

    2016-08-08

    X-ray phase contrast and dark-field imaging techniques provide important and complementary information that is inaccessible to the conventional absorption contrast imaging. Both grating-based imaging (GBI) and speckle-based imaging (SBI) are able to retrieve multi-modal images using synchrotron as well as lab-based sources. However, no systematic comparison has been made between the two techniques so far. We present an experimental comparison between GBI and SBI techniques with synchrotron radiation X-ray source. Apart from the simple experimental setup, we find SBI does not suffer from the issue of phase unwrapping, which can often be problematic for GBI. In addition, SBI is also superior to GBI since two orthogonal differential phase gradients can be simultaneously extracted by one dimensional scan. The GBI has less stringent requirements for detector pixel size and transverse coherence length when a second or third grating can be used. This study provides the reference for choosing the most suitable technique for diverse imaging applications at synchrotron facility.

  1. Synchrotron-based small-angle X-ray scattering (SAXS) of proteins in solution

    PubMed Central

    Skou, Soren; Gillilan, Richard E

    2015-01-01

    Summary With recent advances in data analysis algorithms, X-ray detectors, and synchrotron sources, small-angle X-ray scattering (SAXS) has become much more accessible to the structural biology community than ever before. Although limited to ~10 Å resolution, SAXS can provide a wealth of structural information on biomolecules in solution and is compatible with a wide range of experimental conditions. SAXS is thus an attractive alternative when crystallography is not possible. Moreover, advanced usage of SAXS can provide unique insight into biomolecular behavior that can only be observed in solution, such as large conformational changes and transient protein-protein interactions. Unlike crystal diffraction data, however, solution scattering data are subtle in appearance, highly sensitive to sample quality and experimental errors, and easily misinterpreted. In addition, synchrotron beamlines that are dedicated to SAXS are often unfamiliar to the non-specialist. Here, we present a series of procedures that can be used for SAXS data collection and basic cross-checks designed to detect and avoid aggregation, concentration effects, radiation damage, buffer mismatch, and other common problems. The protein, human serum albumin (HSA), serves as a convenient and easily replicated example of just how subtle these problems can sometimes be, but also of how proper technique can yield pristine data even in problematic cases. Because typical data collection times at a synchrotron are only one to several days, we recommend that the sample purity, homogeneity, and solubility be extensively optimized prior to the experiment. PMID:24967622

  2. Investigation of artefact sources in synchrotron microtomography via virtual X-ray imaging

    NASA Astrophysics Data System (ADS)

    Vidal, F. P.; Létang, J. M.; Peix, G.; Cloetens, P.

    2005-06-01

    Qualitative and quantitative use of volumes reconstructed by computed tomography (CT) can be compromised due to artefacts which corrupt the data. This article illustrates a method based on virtual X-ray imaging to investigate sources of artefacts which occur in microtomography using synchrotron radiation. In this phenomenological study, different computer simulation methods based on physical X-ray properties, eventually coupled with experimental data, are used in order to compare artefacts obtained theoretically to those present in a volume acquired experimentally, or to predict them for a particular experimental setup. The article begins with the presentation of a synchrotron microtomographic slice of a reinforced fibre composite acquired at the European Synchrotron Radiation Facility (ESRF) containing streak artefacts. This experimental context is used as the motive throughout the paper to illustrate the investigation of some artefact sources. First, the contribution of direct radiation is compared to the contribution of secondary radiations. Then, the effect of some methodological aspects are detailed, including under-sampling, sample and camera misalignment, sample extending outside of the field of view and photonic noise. The effect of harmonic components present in the experimental spectrum are also simulated. Afterwards, detector properties, such as its impulse response or defective pixels, are taken into account. Finally, the importance of phase contrast effects is evaluated. In the last section, this investigation is discussed by putting emphasis on the experimental context which is used throughout this paper.

  3. Development of a speckle-based portable device for in situ metrology of synchrotron X-ray mirrors

    PubMed Central

    Kashyap, Yogesh; Wang, Hongchang; Sawhney, Kawal

    2016-01-01

    A portable device for in situ metrology of synchrotron X-ray mirrors based on the near-field speckle scanning technique has been developed. Ultra-high angular sensitivity is achieved by scanning a piece of abrasive paper or filter membrane in the X-ray beam. In addition to the compact setup and ease of implementation, a user-friendly graphical user interface has been developed to ensure that optimizing active X-ray mirrors is simple and fast. The functionality and feasibility of this device have been demonstrated by characterizing and optimizing X-ray mirrors. PMID:27577767

  4. Development of a speckle-based portable device for in situ metrology of synchrotron X-ray mirrors.

    PubMed

    Kashyap, Yogesh; Wang, Hongchang; Sawhney, Kawal

    2016-09-01

    A portable device for in situ metrology of synchrotron X-ray mirrors based on the near-field speckle scanning technique has been developed. Ultra-high angular sensitivity is achieved by scanning a piece of abrasive paper or filter membrane in the X-ray beam. In addition to the compact setup and ease of implementation, a user-friendly graphical user interface has been developed to ensure that optimizing active X-ray mirrors is simple and fast. The functionality and feasibility of this device have been demonstrated by characterizing and optimizing X-ray mirrors.

  5. Development of a Time-resolved Soft X-ray Spectrometer for Laser Produced Plasma Experiments

    SciTech Connect

    Cone, K V; Dunn, J; Schneider, M B; Baldis, H A; Brown, G V; Emig, J; James, D L; May, M J; Park, J; Shepherd, R; Widmann, K

    2010-05-12

    A 2400 line/mm variable spaced grating spectrometer (VSG) has been used to measure soft x-ray emission (8-22 {angstrom}) from laser-produced plasma experiments at Lawrence Livermore National Laboratory's Compact Multipulse Terrawatt (COMET) Laser Facility. The spectrometer was coupled to a Kentech x-ray streak camera to study the temporal evolution of soft x-rays emitted from the back of mylar and copper foils irradiated at 10{sup 15} W/cm{sup 2}. The instrument demonstrated a resolving power of {approx} 120 at 19 {angstrom} with a time resolution of 31 ps. The time-resolved copper emission spectrum was consistent with a photodiode monitoring the laser temporal pulse shape and indicated that the soft x-ray emission follows the laser heating of the target. The time and spectral resolution of this diagnostic make it useful for studies of high temperature plasmas.

  6. Simultaneous X-ray fluorescence and scanning X-ray diffraction microscopy at the Australian Synchrotron XFM beamline

    SciTech Connect

    Jones, Michael W. M.; Phillips, Nicholas W.; van Riessen, Grant A.; Abbey, Brian; Vine, David J.; Nashed, Youssef S. G.; Mudie, Stephen T.; Afshar, Nader; Kirkham, Robin; Chen, Bo; Balaur, Eugeniu; de Jonge, Martin D.

    2016-08-11

    Owing to its extreme sensitivity, quantitative mapping of elemental distributionsviaX-ray fluorescence microscopy (XFM) has become a key microanalytical technique. The recent realisation of scanning X-ray diffraction microscopy (SXDM) meanwhile provides an avenue for quantitative super-resolved ultra-structural visualization. The similarity of their experimental geometries indicates excellent prospects for simultaneous acquisition. Here, in both step- and fly-scanning modes, robust, simultaneous XFM-SXDM is demonstrated.

  7. OSO-8 soft X-ray experiment (Wisconsin)

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Information for operating and reducing data from the experiment which was designed to map low energy X-ray background emissions from 130 eV to 35 keV is presented. The detectors, counters, data system, and the gas system are discussed along with the functional operation of the subsystems. A command list indicating preconditions and resulting telemetry response for each command is included.

  8. Emission Angles for Soft X-Ray Coherent Transition Radiation.

    DTIC Science & Technology

    1987-09-01

    possible sources of error are cited. Acceso ;i For NTIS CRA&I i IC TAB L AW 4i 3 TABLE OF CONTENTS I. INTRODUCTION...addition of radiation from multiple foil stacks and the use of transition radiation as a particle beam detector [Ref. 2:p. 3594). E Use of transition...radiation to measure the energy of * electrons in early studies was restricted by the absorption of the x-rays by multiple dielectric foil stacks. The high 7

  9. Design considerations for soft X-ray television imaging detectors

    NASA Technical Reports Server (NTRS)

    Kalata, Kenneth; Golub, Leon

    1988-01-01

    Television sensors for X-rays can be coupled to converters and image intensifiers to obtain active areas, high flux capabilities, quantum efficiency, high time resolution, or ease of construction and operation that may not be obtained with a directly illuminated sensor. A general purpose system which makes use of these capabilities for a number of applications is decribed. Some of the performance characteristics of this type of system are examined, and the expected future developments for such systems are briefly addressed.

  10. Time-resolved soft X-ray core-level photoemission spectroscopy at 880 °C using the pulsed laser and synchrotron radiation and the pulse heating current

    NASA Astrophysics Data System (ADS)

    Abukawa, T.; Yamamoto, S.; Yukawa, R.; Kanzaki, S.; Mukojima, K.; Matsuda, I.

    2017-02-01

    We developed a time-resolved photoemission spectroscopy system for tracking the temporal variation in an electronic state of a heated sample. Our pump-probe method used laser and synchrotron radiation pulses on a silicon surface that was heated by a synchronized pulse current that did not interfere with the measurements. The transient surface photovoltage effect on the Si 2p core spectra was measured from room temperature to 880 °C and was found to be consistent with the thermal carrier distributions in silicon crystals at the corresponding temperatures. This versatile technique may have applications studying molecular dynamics on high temperature surfaces such as in catalytic reactions.

  11. Iron overload of human colon adenocarcinoma cells studied by synchrotron-based X-ray techniques.

    PubMed

    Mihucz, Victor G; Meirer, Florian; Polgári, Zsófia; Réti, Andrea; Pepponi, Giancarlo; Ingerle, Dieter; Szoboszlai, Norbert; Streli, Christina

    2016-04-01

    Fast- and slow-proliferating human adenocarcinoma colorectal cells, HT-29 and HCA-7, respectively, overloaded with transferrin (Tf), Fe(III) citrate, Fe(III) chloride and Fe(II) sulfate were studied by synchrotron radiation total-reflection X-ray spectrometry (TXRF), TXRF-X-ray absorption near edge structure (TXRF-XANES), and micro-X-ray fluorescence imaging to obtain information on the intracellular storage of overloaded iron (Fe). The determined TfR1 mRNA expression for the investigated cells correlated with their proliferation rate. In all cases, the Fe XANES of cells overloaded with inorganic Fe was found to be similar to that of deliquescent Fe(III) sulfate characterized by a distorted octahedral geometry. A fitting model using a linear combination of the XANES of Tf and deliquescent Fe(III) sulfate allowed to explain the near edge structure recorded for HT-29 cells indicating that cellular overload with inorganic Fe results in a non-ferritin-like fast Fe storage. Hierarchical cluster analysis of XANES spectra recorded for Fe overloaded HT-29 and HCA-7 cells was able to distinguish between Fe treatments performed with different Fe species with a 95% hit rate, indicating clear differences in the Fe storage system. Micro-X-ray fluorescence imaging of Fe overloaded HT-29 cells revealed that Fe is primarily located in the cytosol of the cells. By characterizing the cellular Fe uptake, Fe/S content ratios were calculated based on the X-ray fluorescence signals of the analytes. These Fe/S ratios were dramatically lower for HCA-7 treated with organic Fe(III) treatments suggesting dissimilarities from the Tf-like Fe uptake.

  12. Synchrotron radiation-based x-ray reflection and scattering techniques for dimensional nanometrology

    NASA Astrophysics Data System (ADS)

    Krumrey, Michael; Gleber, Gudrun; Scholze, Frank; Wernecke, Jan

    2011-09-01

    Nanoobjects have at least one dimension in the range from 1 to 100 nm. Thus, if radiation is used for dimensional metrology, it should preferably have a wavelength in or below this range. For example, x-ray reflectometry (XRR) using x-ray tubes with Cu Kα radiation is widely used for layer thickness measurements with relative uncertainties of about 1%. By using different monochromator beamlines in the laboratory of PTB at the synchrotron radiation facility BESSY II, any x-ray wavelength from several nanometers down to about 0.1 nm can be selected for dimensional measurements in the nanometer range. Here, XRR is performed at wavelengths in the vicinity of an absorption edge of the chemical elements involved in order to enhance the contrast for layer systems like SiO2/Si which are difficult to resolve with Cu Kα radiation. By using longer wavelengths of around 2 nm, even an oxide layer and a thin carbonaceous contamination layer on a strongly curved spherical surface were separated, as required for measurements at 95 mm diameter silicon spheres within the international Avogadro project for the new definition of the kilogram. For nanoparticles in suspension, small angle x-ray scattering (SAXS) is the method of choice for dimensional metrology. This ensemble technique requires intense, monochromatic x-rays of low divergence. From the scattering pattern, the particle diameter and the size distribution are obtained. Moreover, the dimensional properties of nanostructured surfaces and nanoparticles on surfaces have been studied by grazing incidence SAXS (GISAXS), combining small angle scattering with the reflection geometry known from XRR. The diameters of gold nanoparticles obtained by SAXS and GISAXS are in very good agreement.

  13. Probing deformation substructure by synchrotron X-ray diffraction and dislocation dynamics modelling.

    PubMed

    Korsunsky, Alexander M; Hofmann, Felix; Song, Xu; Eve, Sophie; Collins, Steve P

    2010-09-01

    Materials characterization at the nano-scale is motivated by the desire to resolve the structural aspects and deformation behavior at length scales relevant to those mechanisms that define the novel and unusual properties of nano-structured materials. A range of novel techniques has recently become accessible with the help of synchrotron X-ray beams that can be focused down to spot sizes of less than a few microns on the sample. The unique combination of tunability (energy selection), parallelism and brightness of synchrotron X-ray beams allows their use for high resolution diffraction (determination of crystal structure and transformations, analysis of dislocation sub-structures, orientation and texture analysis, strain mapping); small angle X-ray scattering (analysis of nano-scale voids and defects; orientation analysis) and imaging (radiography and tomography). After a brief review of the state-of-the-art capabilities for monochromatic and white beam synchrotron diffraction, we consider the usefulness of these techniques for the task of bridging the gap between experiment and modeling. Namely, we discuss how the experiments can be configured to provide information relevant to the validation and improvement of modeling approaches, and also how the results of various simulations can be post-processed to improve the possibility of (more or less) direct comparison with experiments. Using the example of some recent experiments carried out on beamline 116 at Diamond Light Source near Oxford, we discuss how such experimental results can be interpreted in view and in conjunction with numerical deformation models, particularly those incorporating dislocation effects, e.g., finite-element based pseudo-continuum strain gradient formulations, and discrete dislocation simulations. Post-processing of FE and discrete dislocation simulations is described, illustrating the kind of information that can be extracted from comparisons between modeling and experimental data.

  14. Correlative Analysis of hard and Soft X-rays in Solar Flares using CGRO/BATSE and YOHKOH

    NASA Technical Reports Server (NTRS)

    Zarro, Dominic M.

    1996-01-01

    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 Bragg Crystal Spectrometer (BCS) and Soft X-ray telescope (SXT) on the Japanese Yohkoh spacecraft.

  15. Synchrotron X-ray Studies of the Keel of the Short-Spined Sea Urchin Lytechinus variegatus: Absorption Microtomography (microCT) and Small Beam Diffraction Mapping

    SciTech Connect

    Stock, S. R.; Barss, J.; Dahl, T.; Veis, A.; Almer, J. D.; De Carlo, F.

    2003-05-01

    In sea urchin teeth, the keel plays an important structural role, and this paper reports results of microstructural characterization of the keel of Lytechinus variegatus using two noninvasive synchrotron x-ray techniques: x-ray absorption microtomography (microCT) and x-ray diffraction mapping. MicroCT with 14 keV x-rays mapped the spatial distribution of mineral at the 1.3 microm level in a millimeter-sized fragment of a mature portion of the keel. Two rows of low absorption channels (i.e., primary channels) slightly less than 10 microm in diameter were found running linearly from the flange to the base of the keel and parallel to its sides. The primary channels paralleled the oral edge of the keel, and the microCT slices revealed a planar secondary channel leading from each primary channel to the side of the keel. The primary and secondary channels were more or less coplanar and may correspond to the soft tissue between plates of the carinar process. Transmission x-ray diffraction with 80.8 keV x-rays and a 0.1 mm beam mapped the distribution of calcite crystal orientations and the composition Ca(1-x)Mg(x)CO(3) of the calcite. Unlike the variable Mg concentration and highly curved prisms found in the keel of Paracentrotus lividus, a constant Mg content (x = 0.13) and relatively little prism curvature was found in the keel of Lytechinus variegatus.

  16. Porosity characterization of fiber-reinforced ceramic matrix composite using synchrotron X-ray computed tomography

    NASA Astrophysics Data System (ADS)

    Zou, C.; Marrow, T. J.; Reinhard, C.; Li, B.; Zhang, C.; Wang, S.

    2016-03-01

    The pore structure and porosity of a continuous fiber reinforced ceramic matrix composite has been characterized using high-resolution synchrotron X-ray computed tomography (XCT). Segmentation of the reconstructed tomograph images reveals different types of pores within the composite, the inter-fiber bundle open pores displaying a "node-bond" geometry, and the intra-fiber bundle isolated micropores showing a piping shape. The 3D morphology of the pores is resolved and each pore is labeled. The quantitative filtering of the pores measures a total porosity 8.9% for the composite, amid which there is about 7.1~ 9.3% closed micropores.

  17. An x-ray fluorescence study of lake sediments from ancient Turkey using synchrotron radiation.

    SciTech Connect

    Alatas, A.; Alp, E. E.; Friedman, E. S.; Jennings, G.; Johnson, C. E.; Lai, B.; Mini, S. M.; Sato, Y.; Wilkinson, T. J.; Yener, K. A.

    1999-03-10

    Sediments from relic Lake Golbasi were analyzed by X-ray fluorescence with synchrotrons radiation to determine changes in element concentrations over time with selected elements serving as proxies for environmental change. Increases in Ca and Sr suggest soil formation during a dry period, from ca. 4500 BC to ca. 200 AD at which point K, Rb, Zr, Ti, and Y increase, indicating the return of a wet environment. Soil erosion, represented by Cr and Ni, increases ca. 7000 BC, probably as a consequence of environmental change, prior to suggested exploitation of natural resources by the newly urbanized society of the third millennium BC.

  18. A portable molecular beam epitaxy system for in situ x-ray investigations at synchrotron beamlines

    SciTech Connect

    Slobodskyy, T.; Schroth, P.; Grigoriev, D.; Minkevich, A. A.; Baumbach, T.; Hu, D. Z.; Schaadt, D. M.

    2012-10-15

    A portable synchrotron molecular beam epitaxy (MBE) system is designed and applied for in situ investigations. The growth chamber is equipped with all the standard MBE components such as effusion cells with shutters, main shutter, cooling shroud, manipulator, reflection high energy electron diffraction setup, and pressure gauges. The characteristic feature of the system is the beryllium windows which are used for in situ x-ray measurements. An UHV sample transfer case allows in vacuo transfer of samples prepared elsewhere. We describe the system design and demonstrate its performance by investigating the annealing process of buried InGaAs self-organized quantum dots.

  19. A portable molecular beam epitaxy system for in situ x-ray investigations at synchrotron beamlines.

    PubMed

    Slobodskyy, T; Schroth, P; Grigoriev, D; Minkevich, A A; Hu, D Z; Schaadt, D M; Baumbach, T

    2012-10-01

    A portable synchrotron molecular beam epitaxy (MBE) system is designed and applied for in situ investigations. The growth chamber is equipped with all the standard MBE components such as effusion cells with shutters, main shutter, cooling shroud, manipulator, reflection high energy electron diffraction setup, and pressure gauges. The characteristic feature of the system is the beryllium windows which are used for in situ x-ray measurements. An UHV sample transfer case allows in vacuo transfer of samples prepared elsewhere. We describe the system design and demonstrate its performance by investigating the annealing process of buried InGaAs self-organized quantum dots.

  20. Load transfer in bovine plexiform bone determined by synchrotron x-ray diffraction.

    SciTech Connect

    Akhtar, R.; Daymond, M.; Almer, J.; Mummery, P.; The Univ. of Manchester; Queen's Univ.

    2008-02-01

    High-energy synchrotron x-ray diffraction (XRD) has been used to quantify load transfer in bovine plexiform bone. By using both wide-angle and small-angle XRD, strains in the mineral as well as the collagen phase of bone were measured as a function of applied compressive stress. We suggest that a greater proportion of the load is borne by the more mineralized woven bone than the lamellar bone as the applied stress increases. With a further increase in stress, load is shed back to the lamellar regions until macroscopic failure occurs. The reported data fit well with reported mechanisms of microdamage accumulation in bovine plexiform bone.

  1. ShadowOui: a new visual environment for X-ray optics and synchrotron beamline simulations

    PubMed Central

    Sánchez del Río, Manuel

    2016-01-01

    A new computer environment to perform simulations on synchrotron experiments has been designed. It performs ray-tracing simulations using the popular ray-tracing code SHADOW. With this new application one can define, in a very easy and elegant way, one or several optical systems (beamlines) and perform calculations of the propagation of the X-ray beam through it. Many complementary tools and supplementary calculations improve and extend the functionality of SHADOW to deal with complex optical system optimization, including compound optical elements, iterative calculations, some sample simulations, and implementing corrections for wave optics via a hybrid model. PMID:27787241

  2. Dynamic crystal rotation resolved by high-speed synchrotron X-ray Laue diffraction

    SciTech Connect

    Huang, J. W.; E, J. C.; Huang, J. Y.; Sun, T.; Fezzaa, K.; Luo, S. N.

    2016-03-30

    Dynamic compression experiments are performed on single-crystal Si under split Hopkinson pressure bar loading, together with simultaneous high-speed (250–350 ns resolution) synchrotron X-ray Laue diffraction and phase-contrast imaging. A methodology is presented which determines crystal rotation parameters,i.e.instantaneous rotation axes and angles, from two unindexed Laue diffraction spots. Two-dimensional translation is obtained from dynamic imaging by a single camera. High-speed motion of crystals, including translation and rotation, can be tracked in real timeviasimultaneous imaging and diffraction.

  3. Dynamic crystal rotation resolved by high-speed synchrotron X-ray Laue diffraction

    PubMed Central

    Huang, J. W.; E, J. C.; Huang, J. Y.; Sun, T.; Fezzaa, K.; Luo, S. N.

    2016-01-01

    Dynamic compression experiments are performed on single-crystal Si under split Hopkinson pressure bar loading, together with simultaneous high-speed (250–350 ns resolution) synchrotron X-ray Laue diffraction and phase-contrast imaging. A methodology is presented which determines crystal rotation parameters, i.e. instantaneous rotation axes and angles, from two unindexed Laue diffraction spots. Two-dimensional translation is obtained from dynamic imaging by a single camera. High-speed motion of crystals, including translation and rotation, can be tracked in real time via simultaneous imaging and diffraction. PMID:27140150

  4. Microscopy and elemental analysis in tissue samples using computed microtomography with synchrotron x-rays

    SciTech Connect

    Spanne, P.; Rivers, M.L.

    1988-01-01

    The initial development shows that CMT using synchrotron x-rays can be developed to ..mu..m spatial resolution and perhaps even better. This creates a new microscopy technique which is of special interest in morphological studies of tissues, since no chemical preparation or slicing of the sample is necessary. The combination of CMT with spatial resolution in the ..mu..m range and elemental mapping with sensitivity in the ppM range results in a new tool for elemental mapping at the cellular level. 7 refs., 1 fig.

  5. Compressible cake filtration: monitoring cake formation and shrinkage using synchrotron X-rays

    SciTech Connect

    Bierck, B.R.; Wells, S.A.; Dick, R.I.

    1988-05-01

    High energy, highly collimated X-rays produced at the Cornell High Energy Synchrotron Sources (CHESS) enabled real-time suspended solids concentration measurements each second with 0.5 mm vertical separation in a kaolin filter cake. Suspended solids concentration profiles reflected expected effects of cumulative fluid drag forces. Shrinkage caused a significant increase in average cake suspended solids concentration after expiration of the slurry, and the saturated cake ultimately formed was virtually homogeneous. Shrinkage is consolidation under compressive forces created when capillary menisci form at air/liquid interfaces, and has a significant effect on cake structure in latter stages of compressible cake filtration.

  6. Synchrotron total reflection X-ray fluorescence at BL-16 microfocus beamline of Indus-2

    SciTech Connect

    Tiwari, M. K. Singh, A. K. Das, Gangadhar Chowdhury, Anupam Lodha, G. S.

    2014-04-24

    Determination of ultra trace elements is important in many disciplines both in basic and applied sciences. Numerous applications show their importance in medical science, environmental science, materials science, food processing and semiconductor industries and in maintaining the quality control of ultra pure chemicals and reagents. We report commissioning of a synchrotron based total reflection x-ray fluorescence (TXRF) facility on the BL-16 microfocus beamline of Indus-2. This paper describes the performance of the BL-16 TXRF spectrometer and the detailed description of its capabilities through examples of measured results.

  7. Poly (methyl methacrylate) Formation and Patterning Initiated by Synchrotron X-ray Illumination

    SciTech Connect

    Xiao, J.; Je, J. H.; Wang, C. H.; Yang, T. Y.; Hwu, Y.

    2007-01-19

    A facile radiation method was developed to obtain micro-sized poly (methyl methacrylate) (PMMA) particles and create patterned coating on different substrates by a synchrotron x-ray induced dispersion polymerization. The polymerization of MMA monomer and well defined patterning was successfully realized. The produced PMMA particles and patterning were characterized by Fourier transformation infrared (FTIR), 1H-Nuclear Magnetic Resonance (NMR), and Scanning Electron Microscope (SEM). The observed patterning contrast essentially derived from a variation of size, density and morphology of particles and the type of substrate materials used.

  8. Synchrotron total reflection X-ray fluorescence at BL-16 microfocus beamline of Indus-2

    NASA Astrophysics Data System (ADS)

    Tiwari, M. K.; Singh, A. K.; Das, Gangadhar; Chowdhury, Anupam; Lodha, G. S.

    2014-04-01

    Determination of ultra trace elements is important in many disciplines both in basic and applied sciences. Numerous applications show their importance in medical science, environmental science, materials science, food processing and semiconductor industries and in maintaining the quality control of ultra pure chemicals and reagents. We report commissioning of a synchrotron based total reflection x-ray fluorescence (TXRF) facility on the BL-16 microfocus beamline of Indus-2. This paper describes the performance of the BL-16 TXRF spectrometer and the detailed description of its capabilities through examples of measured results.

  9. A Optical Synchrotron Nebula around the X-Ray Pulsar 0540-693

    NASA Astrophysics Data System (ADS)

    Chanan, G.; Helfand, D.; Reynolds, S.

    The authors report the discovery of extended optical continuum emission around the recently discovered 50 ms X-ray pulsar in the supernova remnant 0540-693. Exposures in blue and red broadband filters made with the CTIO 4 m telescope and prime focus CCD show a center-brightened but clearly extended nebula about 4arcsec in diameter (FWHM), while an image in an [O III] filter shows an 8arcsec diameter shell (as reported earlier) which encloses the continuum source. 0540-693 is a system very similar to the Crab nebula and represents the second detection of optical synchrotron radiation in a supernova remnant.

  10. Synchrotron X-ray, photoluminescence, and quantum chemistry studies of bismuth-embedded dehydrated zeolite Y.

    PubMed

    Sun, Hong-Tao; Matsushita, Yoshitaka; Sakka, Yoshio; Shirahata, Naoto; Tanaka, Masahiko; Katsuya, Yoshio; Gao, Hong; Kobayashi, Keisuke

    2012-02-15

    For the first time, direct experimental evidence of the formation of monovalent Bi (i.e., Bi(+)) in zeolite Y is provided based on the analysis of high-resolution synchrotron powder X-ray diffraction data. Photoluminescence results as well as quantum chemistry calculations suggest that the substructures of Bi(+) in the sodalite cages contribute to the ultrabroad near-infrared emission. These results not only enrich the well-established spectrum of optically active zeolites and deepen the understanding of bismuth related photophysical behaviors, but also may raise new possibilities for the design and synthesis of novel hybrid nanoporous photonic materials activated by other heavier p-block elements.

  11. Synchrotron X-ray imaging of nanomagnetism in meteoritic metal (Invited)

    NASA Astrophysics Data System (ADS)

    Bryson, J. F.; Herrero Albillos, J.; Kronast, F.; Tyliszczak, T.; Redfern, S. A.; van der Laan, G.; Harrison, R. J.

    2013-12-01

    It is becoming increasingly apparent that a wealth of paleomagnetic information is stored at the nanoscale within natural samples. To date, this nanopaleomagetism has been investigated using high resolution magnetic microscopies, such as electron holography. Although unparalleled in its spatial resolution, electron holography produces images that are indirectly related to the magnetisation state of the sample, introducing ambiguity when interpreting magnetisation information. Holography also requires extensive off-line processing, making it unsuitable for studying dynamic processes, and the sample preparation negates the study of natural remanences. Here we demonstrate the capabilities of a new generation of nanomagnetic imaging methods using synchrotron X-ray radiation. X-rays tuned to an elemental absorption edge can display differing excitation probabilities depending on the orientation of an electron's magnetic moment relative to that of the X-ray beam. This is achieved by introducing an angular momentum to the photon through circular polarisation, resulting in an absorption signal that is proportional to the projection of the magnetic moment on to the X-ray beam direction. We introduce and compare two experimental set-ups capable of spatially resolving these signals to form a high-resolution magnetisation map: photoemission electron microscopy and scanning transmission electron microscopy. Both techniques provide measurements of magnetisation with 30-50nm resolution and elemental specificity. Photoemission electron microscopy can be used also to create maps of all three of the spatial components of magnetisation and investigate dynamic magnetic switching processes. The full capabilities of X-ray imaging are demonstrated through the application of both of these techniques to meteoritic metal. We show that the 'cloudy zone' within iron meteorites contains nanoscale islands of tetrataenite (FeNi) that are populated equally by all three possible magnetic easy axes

  12. The soft X-ray excess in Einstein quasar spectra

    NASA Technical Reports Server (NTRS)

    Masnou, J. L.; Wilkes, B. J.; Elvis, M.; Mcdowell, J. C.; Arnaud, K. A.

    1992-01-01

    An SNR-limited subsample of 14 quasars from the Wilkes and Elvis (1987) sample is presently investigated for low-energy excess above a high-energy power law in the X-ray spectra obtained by the Einstein Imaging Proportional Counter. A significant excess that is 1-6 times as strong as the high-energy component at 0.2 keV is noted in eight of the 14 objects. In the case of 3C273, multiple observations show the excess to be variable.

  13. Young Stellar Objects from Soft to Hard X-rays

    NASA Astrophysics Data System (ADS)

    Güdel, Manuel

    2009-05-01

    Magnetically active stars are the sites of efficient particle acceleration and plasma heating, processes that have been studied in detail in the solar corona. Investigation of such processes in young stellar objects is much more challenging due to various absorption processes. There is, however, evidence for violent magnetic energy release in very young stellar objects. The impact on young stellar environments (e.g., circumstellar disk heating and ionization, operation of chemical networks, photoevaporation) may be substantial. Hard X-ray devices like those carried on Simbol-X will establish a basis for detailed studies of these processes.

  14. Synchrotron X-ray CT characterization of titanium parts fabricated by additive manufacturing. Part II. Defects.

    PubMed

    Scarlett, Nicola Vivienne Yorke; Tyson, Peter; Fraser, Darren; Mayo, Sheridan; Maksimenko, Anton

    2016-07-01

    Synchrotron X-ray tomography (SXRT) has been applied to the study of defects within three-dimensional printed titanium parts. These parts were made using 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. The samples represent a selection of complex shapes with a variety of internal morphologies. Inspection via SXRT has revealed a number of defects which may not otherwise have been seen. The location and nature of such defects combined with detailed knowledge of the process conditions can contribute to understanding the interplay between design and manufacturing strategy. This fundamental understanding may subsequently be incorporated into process modelling, prediction of properties and the development of robust methodologies for the production of defect-free parts.

  15. Coherence properties of focused X-ray beams at high-brilliance synchrotron sources

    PubMed Central

    Singer, Andrej; Vartanyants, Ivan A.

    2014-01-01

    An analytical approach describing properties of focused partially coherent X-ray beams is presented. The method is based on the results of statistical optics and gives both the beam size and transverse coherence length at any distance behind an optical element. In particular, here Gaussian Schell-model beams and thin optical elements are considered. Limiting cases of incoherent and fully coherent illumination of the focusing element are discussed. The effect of the beam-defining aperture, typically used in combination with focusing elements at synchrotron sources to improve transverse coherence, is also analyzed in detail. As an example, the coherence properties in the focal region of compound refractive lenses at the PETRA III synchrotron source are analyzed. PMID:24365911

  16. Soft X-ray bremsstrahlung and fluorescent line production in the atmosphere by low energy electrons

    NASA Technical Reports Server (NTRS)

    Kraushaar, W. L.

    1974-01-01

    The effect of low energy quasi-trapped or precipitating electrons which impact on the counter windows of soft X-ray detectors are discussed. The errors caused by X-rays produced in the residual atmosphere above a rocket-borne detector because of the resemblance to X-rays of cosmic origin are examined. The design and development of counter windows which make it possible to identify the atmospherically produced X-rays are described. Curves are presented to show the following: (1) preliminary low energy electron data from Atmospheric Explorer C, (2) X-ray flux in electron-excited nitrogen and oxygen, (3) typical proportional counter response to low energy cosmic rays, and (4) proportional counter response to X-radiation produced by electrons incident upon a gas of oxygen to nitrogen number of 0.4.

  17. Demonstration of synchrotron x-ray phase contrast imaging computed tomography of infiltrative transitional cell carcinoma of the prostatic urethra in a dog

    PubMed Central

    Montgomery, James E.; Wesolowski, Michal J.; Wolkowski, Bailey; Chibbar, Rajni; Snead, Elisabeth C. R.; Singh, Jaswant; Pettitt, Murray; Malhi, Pritpal S.; Barboza, Trinita; Adams, Gregg

    2016-01-01

    Abstract. Prostatic urethral transitional cell carcinoma with prostatic invasion in a dog was imaged with abdominal radiography and abdominal ultrasonography antemortem. Synchrotron in-line x-ray phase contrast imaging computed tomography (XPCI-CT) was performed on the prostate ex vivo at the Canadian Light Source Synchrotron and compared to histology. XPCI-CT imaging provides greater soft tissue contrast than conventional absorption-based x-ray imaging modalities, permitting visualization of regions of inflammatory cell infiltration, differentiation of invasive versus noninvasive tumor regions, and areas of necrosis and mineralization. This represents the first report of XPCI-CT images of an invasive prostatic urothelial neoplasm in a dog. PMID:27014719

  18. Steady X-Ray Synchrotron Emission in the Northeastern Limb of SN 1006

    NASA Technical Reports Server (NTRS)

    Katsuda, Satoru; Petre, Robert; Mori, Koji; Reynolds, Stephen; Long, Knox; Winkler, P.; Tsunemi, Hiroshi

    2010-01-01

    We investigate time variations and detailed spatial structures of X-ray synchrotron emission in the northeastern limb of SN 1006, using two Chandra observations taken in 2000 and 2008. We extract spectra from a number of small ([approx]10'') regions. After taking account of proper motion and isolating the synchrotron from the thermal emission, we study time variations in the synchrotron emission in the small regions. We find that there are no regions showing strong flux variations. Our analysis shows an apparent flux decline in the overall synchrotron flux of [approx]4% at high energies, but we suspect that this is mostly a calibration effect, and that flux is actually constant to [approx]1%. This is much less than the variation found in other remnants where it was used to infer magnetic-field strengths up to 1 mG. We attribute the lack of variability to the smoothness of the synchrotron morphology, in contrast to the small-scale knots found to be variable in other remnants. The smoothness is to be expected for a Type Ia remnant encountering uniform material. Finally, we find a spatial correlation between the flux and the cutoff frequency in synchrotron emission. The simplest interpretation is that the cutoff frequency depends on the magnetic-field strength. This would require that the maximum energy of accelerated electrons is not limited by synchrotron losses, but by some other effect. Alternatively, the rate of particle injection and acceleration may vary due to some effect not yet accounted for, such as a dependence on shock obliquity.

  19. On the Nature of Soft X-Ray Radiation in Comet Hyakutake 1996 B2

    NASA Astrophysics Data System (ADS)

    Krasnopolsky, V. A.

    1996-09-01

    EUVE and ROSAT observations of comet Hyakutake revealed radiation in the soft X-ray with an intensity in the order of 0.03 ph cm(-2) s(-1) at 0.12 a.u. from the comet. We discuss and develop methods to calculate emission of soft X-ray photons in cometary dust and gas by the following processes: (1) scattering and (2) fluorescence of solar X-rays; (3) K- and L-shell ionization by solar-wind protons and (4) electrons; (5) bremsstrahlung of solar-wind electrons; (6) cometary magnetospheric substorms; (7) collisions with interplanetary dust particles; and (8) the presence of very small particles with mass in the order of 10(-19) g in comets. These particles were detected in comet Halley by Utterback and Kissel (Astron. J. 100, 1315, 1990) using the PUMA and PIA dust analyzers from the Vega and Giotto spacecraft. Of all these processes, only very strong substorms and scattering, to a lesser extent, fluorescence and bremsstrahlung by very small particles are capable to produce the measured intensity of soft X-ray. Appearance of strong substorms during each observation event is not probable. Very small particles are a more plausible explanation of the observed soft X-ray emission. However, the mean particle mass of 4.6x 10(-19) g suggested by Utterback and Kissel implies that the total production of these particles exceeds that of gas by a factor of 3.6 (in mass) and is inconsistent with the polarization and color of comet Halley. Both polarization and color require a reduction of the mean mass to (1-2)x 10(-19) g. This reduction strongly affects the visible brightness of the particles, which is proportional to m(2) , with a relatively weak effect on the soft X-ray. Spatial distribution of soft X-ray in comet Hyakutake is consistent with the sunward ejection of dust (Krasnopolsky et al., Astron. Astrophys. 187, 707, 1987). Soft X-ray observations of comets may be a tool for the study and diagnostics of very small particles. According to current models, solar soft X-ray

  20. First in-flight synchrotron X-ray absorption and photoemission study of carbon soot nanoparticles

    NASA Astrophysics Data System (ADS)

    Ouf, F.-X.; Parent, P.; Laffon, C.; Marhaba, I.; Ferry, D.; Marcillaud, B.; Antonsson, E.; Benkoula, S.; Liu, X.-J.; Nicolas, C.; Robert, E.; Patanen, M.; Barreda, F.-A.; Sublemontier, O.; Coppalle, A.; Yon, J.; Miserque, F.; Mostefaoui, T.; Regier, T. Z.; Mitchell, J.-B. A.; Miron, C.

    2016-11-01

    Many studies have been conducted on the environmental impacts of combustion generated aerosols. Due to their complex composition and morphology, their chemical reactivity is not well understood and new developments of analysis methods are needed. We report the first demonstration of in-flight X-ray based characterizations of freshly emitted soot particles, which is of paramount importance for understanding the role of one of the main anthropogenic particulate contributors to global climate change. Soot particles, produced by a burner for several air-to-fuel ratios, were injected through an aerodynamic lens, focusing them to a region where they interacted with synchrotron radiation. X-ray photoelectron spectroscopy and carbon K-edge near-edge X-ray absorption spectroscopy were performed and compared to those obtained for supported samples. A good agreement is found between these samples, although slight oxidation is observed for supported samples. Our experiments demonstrate that NEXAFS characterization of supported samples provides relevant information on soot composition, with limited effects of contamination or ageing under ambient storage conditions. The highly surface sensitive XPS experiments of airborne soot indicate that the oxidation is different at the surface as compared to the bulk probed by NEXAFS. We also report changes in soot’s work function obtained at different combustion conditions.

  1. First in-flight synchrotron X-ray absorption and photoemission study of carbon soot nanoparticles

    PubMed Central

    Ouf, F.-X.; Parent, P.; Laffon, C.; Marhaba, I.; Ferry, D.; Marcillaud, B.; Antonsson, E.; Benkoula, S.; Liu, X.-J.; Nicolas, C.; Robert, E.; Patanen, M.; Barreda, F.-A.; Sublemontier, O.; Coppalle, A.; Yon, J.; Miserque, F.; Mostefaoui, T.; Regier, T. Z.; Mitchell, J.-B. A.; Miron, C.

    2016-01-01

    Many studies have been conducted on the environmental impacts of combustion generated aerosols. Due to their complex composition and morphology, their chemical reactivity is not well understood and new developments of analysis methods are needed. We report the first demonstration of in-flight X-ray based characterizations of freshly emitted soot particles, which is of paramount importance for understanding the role of one of the main anthropogenic particulate contributors to global climate change. Soot particles, produced by a burner for several air-to-fuel ratios, were injected through an aerodynamic lens, focusing them to a region where they interacted with synchrotron radiation. X-ray photoelectron spectroscopy and carbon K-edge near-edge X-ray absorption spectroscopy were performed and compared to those obtained for supported samples. A good agreement is found between these samples, although slight oxidation is observed for supported samples. Our experiments demonstrate that NEXAFS characterization of supported samples provides relevant information on soot composition, with limited effects of contamination or ageing under ambient storage conditions. The highly surface sensitive XPS experiments of airborne soot indicate that the oxidation is different at the surface as compared to the bulk probed by NEXAFS. We also report changes in soot’s work function obtained at different combustion conditions. PMID:27883014

  2. Absorption and Phase Contrast X-Ray Imaging in Paleontology Using Laboratory and Synchrotron Sources.

    PubMed

    Bidola, Pidassa; Stockmar, Marco; Achterhold, Klaus; Pfeiffer, Franz; Pacheco, Mírian L A F; Soriano, Carmen; Beckmann, Felix; Herzen, Julia

    2015-10-01

    X-ray micro-computed tomography (μCT) is commonly used for imaging of samples in biomedical or materials science research. Owing to the ability to visualize a sample in a nondestructive way, X-ray μCT is perfectly suited to inspect fossilized specimens, which are mostly unique or rare. In certain regions of the world where important sedimentation events occurred in the Precambrian geological time, several fossilized animals are studied to understand questions related to their origin, environment, and life evolution. This article demonstrates the advantages of applying absorption and phase-contrast CT on the enigmatic fossil Corumbella werneri, one of the oldest known animals capable of building hard parts, originally discovered in Corumbá (Brazil). Different tomographic setups were tested to visualize the fossilized inner structures: a commercial laboratory-based μCT device, two synchrotron-based imaging setups using conventional absorption and propagation-based phase contrast, and a commercial X-ray microscope with a lens-coupled detector system, dedicated for radiography and tomography. Based on our results we discuss the strengths and weaknesses of the different imaging setups for paleontological studies.

  3. Absorption and Phase Contrast X-Ray Imaging in Paleontology Using Laboratory and Synchrotron Sources

    SciTech Connect

    Bidola, Pidassa; Stockmar, Marco; Achterhold, Klaus; Pfeiffer, Franz; Pacheco, Mirian L.A.F.; Soriano, Carmen; Beckmann, Felix; Herzen, Julia

    2015-10-01

    X-ray micro-computed tomography (CT) is commonly used for imaging of samples in biomedical or materials science research. Owing to the ability to visualize a sample in a nondestructive way, X-ray CT is perfectly suited to inspect fossilized specimens, which are mostly unique or rare. In certain regions of the world where important sedimentation events occurred in the Precambrian geological time, several fossilized animals are studied to understand questions related to their origin, environment, and life evolution. This article demonstrates the advantages of applying absorption and phase-contrast CT on the enigmatic fossil Corumbella werneri, one of the oldest known animals capable of building hard parts, originally discovered in Corumba (Brazil). Different tomographic setups were tested to visualize the fossilized inner structures: a commercial laboratory-based CT device, two synchrotron-based imaging setups using conventional absorption and propagation-based phase contrast, and a commercial X-ray microscope with a lens-coupled detector system, dedicated for radiography and tomography. Based on our results we discuss the strengths and weaknesses of the different imaging setups for paleontological studies.

  4. Basic principles of Synchrotron Radiation-Induced X-Ray Fluorescence (SRXRF)

    SciTech Connect

    Gigante, G.E. . Dipt. di Fisica); Hanson, A.L. )

    1990-05-01

    The characteristic x rays can be used as powerful analytical tools for qualitative and quantitative determination of the major, minor and trace composition of materials. X Ray Fluorescence (XRF) techniques used for almost four decade to solve many problems in basic, applied science, and in industry. The XRF techniques that were developed initially used crystal spectrometers, and are referred to in literature as Wavelength Dispersive (WD) techniques. These WD techniques are still used in many fields and have the merit of a excellent energy resolution that allows for the analysis of many elements while avoiding the overlapping of some fluorescence peaks. They are also particularly useful in a matrix that produces copious quantities of a particular radiation. The principal disadvantages of a WD system are the low efficiency of crystal and the reduced energy region in which crystal spectrometer can be used. In the 1960's, Solid State Detectors (SSD) were developed with energy resolution such that the Energy Dispersive XRF techniques could be developed. These SSD's overcame some of the limitations of the WD techniques. The most attractive characteristics of the EDXRF techniques are in their intrinsic multielemental and non destructive capabilities. The development of the high intensity, high brilliance Synchrotron Radiation (SR) sources have open the possibility to make microanalyses using the XRF techniques, increasing the interest of the scientific community for these techniques. In this paper the basic concepts of the XRF technique are reviewed taking in account the availability of the new sources of x rays. 32 refs., 7 figs.

  5. First in-flight synchrotron X-ray absorption and photoemission study of carbon soot nanoparticles.

    PubMed

    Ouf, F-X; Parent, P; Laffon, C; Marhaba, I; Ferry, D; Marcillaud, B; Antonsson, E; Benkoula, S; Liu, X-J; Nicolas, C; Robert, E; Patanen, M; Barreda, F-A; Sublemontier, O; Coppalle, A; Yon, J; Miserque, F; Mostefaoui, T; Regier, T Z; Mitchell, J-B A; Miron, C

    2016-11-24

    Many studies have been conducted on the environmental impacts of combustion generated aerosols. Due to their complex composition and morphology, their chemical reactivity is not well understood and new developments of analysis methods are needed. We report the first demonstration of in-flight X-ray based characterizations of freshly emitted soot particles, which is of paramount importance for understanding the role of one of the main anthropogenic particulate contributors to global climate change. Soot particles, produced by a burner for several air-to-fuel ratios, were injected through an aerodynamic lens, focusing them to a region where they interacted with synchrotron radiation. X-ray photoelectron spectroscopy and carbon K-edge near-edge X-ray absorption spectroscopy were performed and compared to those obtained for supported samples. A good agreement is found between these samples, although slight oxidation is observed for supported samples. Our experiments demonstrate that NEXAFS characterization of supported samples provides relevant information on soot composition, with limited effects of contamination or ageing under ambient storage conditions. The highly surface sensitive XPS experiments of airborne soot indicate that the oxidation is different at the surface as compared to the bulk probed by NEXAFS. We also report changes in soot's work function obtained at different combustion conditions.

  6. Dose-rate plays a significant role in synchrotron radiation X-ray-induced damage of rodent testes

    PubMed Central

    Chen, Heyu; Wang, Ban; Wang, Caixia; Cao, Wei; Zhang, Jie; Ma, Yingxin; Hong, Yunyi; Fu, Shen; Wu, Fan; Ying, Weihai

    2016-01-01

    Synchrotron radiation (SR) X-ray has significant potential for applications in medical imaging and cancer treatment. However, the mechanisms underlying SR X-ray-induced tissue damage remain unclear. Previous studies on regular X-ray-induced tissue damage have suggested that dose-rate could affect radiation damage. Because SR X-ray has exceedingly high dose-rate compared to regular X-ray, it remains to be determined if dose-rate may affect SR X-ray-induced tissue damage. We used rodent testes as a model to investigate the role of dose-rate in SR X-ray-induced tissue damage. One day after SR X-ray irradiation, we determined the effects of the irradiation of the same dosage at two different dose-rates, 0.11 Gy/s and 1.1 Gy/s, on TUNEL signals, caspase-3 activation and DNA double-strand breaks (DSBs) of the testes. Compared to those produced by the irradiation at 0.11 Gy/s, irradiation at 1.1 Gy/s produced higher levels of DSBs, TUNEL signals, and caspase-3 activation in the testes. Our study has provided the first evidence suggesting that dose-rate could be a significant factor in SR X-ray-induced tissue damage, which may establish a valuable base for utilizing this factor to manipulate the tissue damage in SR X-ray-based medical applications. PMID:28078052

  7. Dose-rate plays a significant role in synchrotron radiation X-ray-induced damage of rodent testes.

    PubMed

    Chen, Heyu; Wang, Ban; Wang, Caixia; Cao, Wei; Zhang, Jie; Ma, Yingxin; Hong, Yunyi; Fu, Shen; Wu, Fan; Ying, Weihai

    2016-01-01

    Synchrotron radiation (SR) X-ray has significant potential for applications in medical imaging and cancer treatment. However, the mechanisms underlying SR X-ray-induced tissue damage remain unclear. Previous studies on regular X-ray-induced tissue damage have suggested that dose-rate could affect radiation damage. Because SR X-ray has exceedingly high dose-rate compared to regular X-ray, it remains to be determined if dose-rate may affect SR X-ray-induced tissue damage. We used rodent testes as a model to investigate the role of dose-rate in SR X-ray-induced tissue damage. One day after SR X-ray irradiation, we determined the effects of the irradiation of the same dosage at two different dose-rates, 0.11 Gy/s and 1.1 Gy/s, on TUNEL signals, caspase-3 activation and DNA double-strand breaks (DSBs) of the testes. Compared to those produced by the irradiation at 0.11 Gy/s, irradiation at 1.1 Gy/s produced higher levels of DSBs, TUNEL signals, and caspase-3 activation in the testes. Our study has provided the first evidence suggesting that dose-rate could be a significant factor in SR X-ray-induced tissue damage, which may establish a valuable base for utilizing this factor to manipulate the tissue damage in SR X-ray-based medical applications.

  8. 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

    The Chandra X-ray Observatory observed the Jovian system for about 24 hours on 25-26 Nov 1999 with the Advanced CCD Imaging Spectrometer (ACIS), in support of the Galileo flyby of Io, and for about 10 hours on 18 Dec 2000 with the imaging array of the High Resolution Camera (HRC-I), in support of the Cassini flyby of Jupiter. Analysis of these data have revealed 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 is about an order of magnitude too weak even during flares from the active Sun to account for the observed x-ray flux from the IPT. Charge-exchange processes, previously invoked to explain Jupiter's x-ray aurora and cometary x-ray emission, and ion stripping by dust grains both fall by orders of magnitude. On the other hand, we calculate that bremsstrahlung emission of soft X-rays from non-thermal electrons in the few hundred to few thousand eV range accounts for roughly one third of the observed x-ray flux from the IPT. Extension of the far ultraviolet (FUV) IPT spectrum likely also contributes.

  9. Soft X-ray spectromicroscopy of cobalt uptake by cement.

    PubMed

    Dähn, Rainer; Vespa, Marika; Tyliszczak, Tolek; Wieland, Erich; Shuh, David K

    2011-03-01

    Scanning transmission X-ray microscopy was used to investigate the speciation and spatial distribution of Co in a Co(II)-doped cement matrix. The aim of this study was to improve the understanding of the heavy metals immobilization process in cement on the molecular level. The Co-doped cement samples hydrated for 30 days with a Co loading of 5000 mg/kg were prepared under normal atmosphere to simulate conditions used for cement-stabilized waste packages. Co 2p(3/2) absorption edge signals were used to determine the spatial distributions of the metal species in the Co(II)-doped cement. The speciation of Co was determined by collecting near-edge X-ray absorption fine structure spectra. On the basis of the shape of the absorption spectra, it was found that Co(II) is partly oxidized to Co(III). The correlation, respectively the anticorrelation with elements such as Al, Si, and Mn, show that Co(II) is predominantly present as Co-hydroxide-like phase as well as Co-phyllosilicate, whereas Co(III) tends to be incorporated only into a CoOOH-like phase. Thus, this study suggests that thermodynamic calculations of Co(II)-immobilization by cementitious systems should take into consideration not only the solubility of Co(II)-hydroxides but also Co(III) phases.

  10. A novel monochromator for ultrashort soft x-ray pulses

    NASA Astrophysics Data System (ADS)

    Brzhezinskaya, Maria; Firsov, Alexander; Holldack, Karsten; Kachel, Torsten; Mitzner, Rolf; Pontius, Niko; Stamm, Christian; Schmidt, Jan-Simon; Föhlisch, Alexander; Erko, Alexei

    2013-05-01

    Reflection zone plates (RZP), which consist of elliptical zone plates fabricated on a total external reflection mirror surface, can be effectively used to produce a monochromatic x-ray beam and to focus it at photon energies below 1400 eV. However, as RZPs are highly chromatic, they can be designed only for one specific photon energy. We alleviate this problem by using a novel approach: a Reflection Zone Plate Array (RZPA). Here, we report about successful implementation of novel monochromator based on RZPAs for experiments with 100 fs time resolution at the upgraded Femtoslicing facility at BESSY-II. Aiming at minimum losses in x-ray flux up to 2000 resolution, we fabricated and used an RZPA as a single optical element for diffraction and focusing. Nine Fresnel lenses, designed for the energies of 410 eV, 543 eV, 644 eV, 715 eV, 786 eV, 861 eV, 1221 eV and 1333 eV which correspond to the absorption edges of NK, O-K, Mn-L, Fe-L, Co-L, Ni-L, Gd-M and Dy-M, were fabricated on the same substrate with a diameter of 100 mm. At resolution E/ΔE up to 2000 all edges of other elements in that range (400-1400 eV) are covered, too.

  11. Synchrotron Powder X-ray Diffraction Study of the Structure and Dehydration Behavior of Sepiolite

    NASA Astrophysics Data System (ADS)

    Post, J. E.; Bish, D. L.; Heaney, P. J.

    2006-05-01

    Sepiolite is a hydrous Mg-silicate clay mineral with fibrous morphology that typically occurs as fine-grained, poorly crystalline masses. It occurs in a wide variety of geological environments and has been mined for centuries because of its many uses, e.g. in the pharmaceutical, fertilizer, and pesticide industries. Its versatile functionality derives from the large surface area and microporosity that are characteristic of the material. In recent years, sepiolite has received considerable attention with regard to the adsorption of organics, for use as a support for catalysts, as a molecular sieve, and as an inorganic membrane for ultrafiltration. Because of its fine-grained and poorly crystalline nature, it has not been possible to study sepiolite's crystal structure using single-crystal X-ray diffraction methods, and consequently many details of the structure are still not well known. In this study, Rietveld refinements using synchrotron powder X-ray diffraction data were used to investigate the crystal structure and dehydration behavior of sepiolite from Durango, Mexico. The room- temperature (RT) sepiolite structure in air compares well with previous models but reveals an additional zeolitic water site. The RT structure under vacuum retained only ~1/8 of the zeolitic water and the volume decreased 1.3%. Real-time, temperature-resolved synchrotron powder X-ray diffraction data and Rietveld refinements were used to investigate the behavior of the sepiolite structure from 300 to 925 K. Rietveld refinements revealed that most of the zeolitic water is lost by ~390 K, accompanied by a decrease in the a and c unit-cell parameters. Above ~600 K the sepiolite structure folds as one-half of the crystallographically bound water is lost. Rietveld refinements of the "anhydrous" sepiolite structure reveal that, in general, unit-cell parameters a, b, â and volume steadily decrease with increasing temperature; there is an obvious change in slope at ~820 K suggesting a phase

  12. Report on recent results of the PERCIVAL soft X-ray imager

    NASA Astrophysics Data System (ADS)

    Khromova, A.; Cautero, G.; Giuressi, D.; Menk, R.; Pinaroli, G.; Stebel, L.; Correa, J.; Marras, A.; Wunderer, C. B.; Lange, S.; Tennert, M.; Niemann, M.; Hirsemann, H.; Smoljanin, S.; Reza, S.; Graafsma, H.; Göttlicher, P.; Shevyakov, I.; Supra, J.; Xia, Q.; Zimmer, M.; Guerrini, N.; Marsh, B.; Sedgwick, I.; Nicholls, T.; Turchetta, R.; Pedersen, U.; Tartoni, N.; Hyun, H. J.; Kim, K. S.; Rah, S. Y.; Hoenk, M. E.; Jewell, A. D.; Jones, T. J.; Nikzad, S.

    2016-11-01

    The PERCIVAL (Pixelated Energy Resolving CMOS Imager, Versatile And Large) soft X-ray 2D imaging detector is based on stitched, wafer-scale sensors possessing a thick epi-layer, which together with back-thinning and back-side illumination yields elevated quantum efficiency in the photon energy range of 125–1000 eV. Main application fields of PERCIVAL are foreseen in photon science with FELs and synchrotron radiation. This requires high dynamic range up to 105 ph @ 250 eV paired with single photon sensitivity with high confidence at moderate frame rates in the range of 10–120 Hz. These figures imply the availability of dynamic gain switching on a pixel-by-pixel basis and a highly parallel, low noise analog and digital readout, which has been realized in the PERCIVAL sensor layout. Different aspects of the detector performance have been assessed using prototype sensors with different pixel and ADC types. This work will report on the recent test results performed on the newest chip prototypes with the improved pixel and ADC architecture. For the target frame rates in the 10–120 Hz range an average noise floor of 14e‑ has been determined, indicating the ability of detecting single photons with energies above 250 eV. Owing to the successfully implemented adaptive 3-stage multiple-gain switching, the integrated charge level exceeds 4 · 106 e‑ or 57000 X-ray photons at 250 eV per frame at 120 Hz. For all gains the noise level remains below the Poisson limit also in high-flux conditions. Additionally, a short overview over the updates on an oncoming 2 Mpixel (P2M) detector system (expected at the end of 2016) will be reported.

  13. Soft x-ray spectromicroscopy development for materials science at the Advanced Light Source

    SciTech Connect

    Warwick, T.; Padmore, H.; Ade, H.; Hitchcock, A.P.; Rightor, E.G.; Tonner, B.P.

    1996-08-01

    Several third generation synchrotron radiation facilities are now operational and the high brightness of these photon sources offers new opportunities for x-ray microscopy. Well developed synchrotron radiation spectroscopy techniques are being applied in new instruments capable of imaging the surface of a material with a spatial resolution smaller than one micron. There are two aspects to this. One is to further the field of surface science by exploring the effects of spatial variations across a surface on a scale not previously accessible to x-ray measurements. The other is to open up new analytical techniques in materials science using x-rays, on a spatial scale comparable to that of the processes or devices to be studied. The development of the spectromicroscopy program at the Advanced Light Source will employ a variety of instruments, some are already operational. Their development and use will be discussed, and recent results will be presented to illustrate their capabilities.

  14. Coordinated soft X-ray and H-alpha observation of solar flares

    NASA Technical Reports Server (NTRS)

    Zarro, D. M.; Canfield, R. C.; Metcalf, T. R.; Lemen, J. R.

    1988-01-01

    Soft X-ray, Ca XIX, and H-alpha observations obtained for a set of four solar flares in the impulsive phase are analyzed. A blue asymmetry was observed in the coronal Ca XIX line during the soft-Xray rise phase in all of the events. A red asymmetry was observed simultaneously in chromospheric H-alpha at spatial locations associated with enhanced flare heating. It is shown that the impulsive phase momentum of upflowing soft X-ray plasma equalled that of the downflowing H-alpha plasma to within an order of magnitude. This supports the explosive chromospheric evaporation model of solar flares.

  15. Observations of the structure and evolution of solar flares with a soft X-ray telescope

    NASA Technical Reports Server (NTRS)

    Vorpahl, J. A.; Gibson, E. G.; Landecker, P. B.; Mckenzie, D. L.; Underwood, J. M.

    1975-01-01

    Soft X ray flare events were observed with the S-056 X-ray telescope that was part of the ATM complement of instruments aboard SKYLAB. Analyses of these data are reported. The observations are summarized and a detailed discussion of the X-ray flare structures is presented. The data indicated that soft X-ray emitted by a flare come primarily from an intense well-defined core surrounded by a region of fainter, more diffuse emission. An analysis of flare evolution indicates evidence for preliminary heating and energy release prior to the main phase of the flare. Core features are found to be remarkably stable and retain their shape throughout a flare. Most changes in the overall configuration seem to be result of the appearance, disappearance or change in brightness of individual features, rather than the restructuring or reorientation of these features. Brief comparisons with several theories are presented.

  16. The soft x-ray instrument for materials studies at the linac coherent light source x-ray free-electron laser

    SciTech Connect

    Schlotter, W. F.; Turner, J. J.; Rowen, M.; Holmes, M.; Messerschmidt, M.; Moeller, S.; Krzywinski, J.; Lee, S.; Coffee, R.; Hays, G.; Heimann, P.; Krupin, O.; Soufli, R.; Fernandez-Perea, M.; Hau-Riege, S.; Kelez, N.; Beye, M.; Gerken, N.; Sorgenfrei, F.; Wurth, W.; and others

    2012-04-15

    The soft x-ray materials science instrument is the second operational beamline at the linac coherent light source x-ray free electron laser. The instrument operates with a photon energy range of 480-2000 eV and features a grating monochromator as well as bendable refocusing mirrors. A broad range of experimental stations may be installed to study diverse scientific topics such as: ultrafast chemistry, surface science, highly correlated electron systems, matter under extreme conditions, and laboratory astrophysics. Preliminary commissioning results are presented including the first soft x-ray single-shot energy spectrum from a free electron laser.

  17. Mapping Metal Elements of Shuangbai Dinosaur Fossil by Synchrotron X-ray Fluorescence Microprobe

    SciTech Connect

    Wang, Y.; Qun, Y; Ablett, J

    2008-01-01

    The metal elements mapping of Shuangbai dinosaur fossil, was obtained by synchrotron x-ray fluorescence (SXRF). Eight elements, Ca, Mn, Fe, Cu, Zn, As, Y and Sr were determined. Elements As and Y were detected for the first time in the dinosaur fossil. The data indicated that metal elements are asymmetrical on fossil section. This is different from common minerals. Mapping metals showed that metal element As is few. The dinosaur most likely belongs to natural death. This is different from Zigong dinosaurs which were found dead from poisoning. This method has been used to find that metals Fe and Mn are accrete, and the same is true for Sr and Y. This study indicated that colloid granule Fe and Mn, as well as Sr and Y had opposite electric charges in lithification process of fossils. By this analysis, compound forms can be ascertained. Synchrotron light source x-ray fluorescence is a complementary method that shows mapping of metal elements at the dinosaur fossil, and is rapid, exact and intuitionist. This study shows that dinosaur fossil mineral imaging has a potential in reconstructing the paleoenvironment and ancient geology.

  18. Synchrotron X-ray measurement techniques for thermal barrier coated cylindrical samples under thermal gradients.

    PubMed

    Siddiqui, Sanna F; Knipe, Kevin; Manero, Albert; Meid, Carla; Wischek, Janine; Okasinski, John; Almer, Jonathan; Karlsson, Anette M; Bartsch, Marion; Raghavan, Seetha

    2013-08-01

    Measurement techniques to obtain accurate in situ synchrotron strain measurements of thermal barrier coating systems (TBCs) applied to hollow cylindrical specimens are presented in this work. The Electron Beam Physical Vapor Deposition coated specimens with internal cooling were designed to achieve realistic temperature gradients over the TBC coated material such as that occurring in the turbine blades of aeroengines. Effects of the circular cross section on the x-ray diffraction (XRD) measurements in the various layers, including the thermally grown oxide, are investigated using high-energy synchrotron x-rays. Multiple approaches for beam penetration including collection, tangential, and normal to the layers, along with variations in collection parameters are compared for their ability to attain high-resolution XRD data from the internal layers. This study displays the ability to monitor in situ, the response of the internal layers within the TBC, while implementing a thermal gradient across the thickness of the coated sample. The thermal setup maintained coating surface temperatures in the range of operating conditions, while monitoring the substrate cooling, for a controlled thermal gradient. Through variation in measurement location and beam parameters, sufficient intensities are obtained from the internal layers which can be used for depth resolved strain measurements. Results are used to establish the various techniques for obtaining XRD measurements through multi-layered coating systems and their outcomes will pave the way towards goals in achieving realistic in situ testing of these coatings.

  19. Solution Synchrotron X-ray Diffraction Reveals Structural Details of Lipid Domains in Ternary Mixtures

    SciTech Connect

    Yuan, J.; Kiss, A; Pramudya, Y; Nguyen, L; Hirst, L

    2009-01-01

    The influence of cholesterol on lipid bilayer structure is significant and the effect of cholesterol on lipid sorting and phase separation in lipid-raft-forming model membrane systems has been well investigated by microscopy methods on giant vesicles. An important consideration however is the influence of fluorescence illumination on the phase state of these lipids and this effect must be carefully minimized. In this paper, we show that synchrotron x-ray scattering on solution lipid mixtures is an effective alternative technique for the identification and characterization of the l o (liquid ordered) and l d (liquid disordered) phases. The high intensity of synchrotron x rays allows the observation of up to 5 orders of diffraction from the l o phase, whereas only two are clearly visible when the l d phase alone is present. This data can be collected in approximately 1 min/sample, allowing rapid generation of phase data. In this paper, we measure the lamellar spacing in both the liquid-ordered and liquid-disordered phases simultaneously, as a function of cholesterol concentration in two different ternary mixtures. We also observe evidence of a third gel-phaselike population at 10-12 mol % cholesterol and determine the thickness of the bilayer for this phase. Importantly we are able to look at phase coexistence in the membrane independent of photoeffects.

  20. [Mapping metal elements of Shuangbai dinosaur fossil by synchrotron X-ray fluorescence microprobe].

    PubMed

    Wang, Yi-Lin; Yang, Qun; Ablett, J M

    2008-05-01

    The metal elements mapping of Shuangbai dinosaur fossil, was obtained by synchrotron x-ray fluorescence (SXRF). Eight elements, Ca, Mn, Fe, Cu, Zn, As, Y and Sr were determined. Elements As and Y were detected for the first time in the dinosaur fossil. The data indicated that metal elements are asymmetrical on fossil section. This is different from common minerals. Mapping metals showed that metal element As is few. The dinosaur most likely belongs to natural death. This is different from Zigong dinosaurs which were found dead from poisoning. This method has been used to find that metals Fe and Mn are accrete, and the same is ture for Sr and Y. This study indicated that colloid granule Fe and Mn, as well as Sr and Y had opposite electric charges in lithification process of fossils. By this analysis, compound forms can be ascertained. Synchrotron light source x-ray fluorescence is a complementary method that shows mapping of metal elements at the dinosaur fossil, and is rapid, exact and intuitionist. This study shows that dinosaur fossil mineral imaging has a potential in reconstructing the paleoenvironment and ancient geology.

  1. SYNCHROTRON BLOB MODEL OF INFRARED AND X-RAY FLARES FROM SAGITTARIUS A*

    SciTech Connect

    Kusunose, Masaaki; Takahara, Fumio E-mail: takahara@vega.ess.sci.osaka-u.ac.jp

    2011-01-01

    Sagittarius A* in the Galactic center harbors a supermassive black hole and exhibits various active phenomena. Besides quiescent emission in radio and submillimeter radiation, flares in the near-infrared (NIR) and X-ray bands are observed to occur frequently. We study a time-dependent model of the flares, assuming that the emission is from a blob ejected from the central object. Electrons obeying a power law with the exponential cutoff are assumed to be injected in the blob for a limited time interval. The flare data of 2007 April 4 were used to determine the values of model parameters. The spectral energy distribution of flare emission is explained by nonthermal synchrotron radiation in the NIR and X-ray bands. The model light curves suggest that electron acceleration is still underway during the rising phase of the flares. GeV {gamma}-rays are also emitted by synchrotron self-Compton scattering, although their luminosity is not strictly constrained by the current model. If the GeV emission is faint, the plasma blob is dominated by the magnetic energy density over the electron kinetic energy density. Observations in the GeV band will clarify the origin of the blob.

  2. Synchrotron X-ray measurement techniques for thermal barrier coated cylindrical samples under thermal gradients

    NASA Astrophysics Data System (ADS)

    Siddiqui, Sanna F.; Knipe, Kevin; Manero, Albert; Meid, Carla; Wischek, Janine; Okasinski, John; Almer, Jonathan; Karlsson, Anette M.; Bartsch, Marion; Raghavan, Seetha

    2013-08-01

    Measurement techniques to obtain accurate in situ synchrotron strain measurements of thermal barrier coating systems (TBCs) applied to hollow cylindrical specimens are presented in this work. The Electron Beam Physical Vapor Deposition coated specimens with internal cooling were designed to achieve realistic temperature gradients over the TBC coated material such as that occurring in the turbine blades of aeroengines. Effects of the circular cross section on the x-ray diffraction (XRD) measurements in the various layers, including the thermally grown oxide, are investigated using high-energy synchrotron x-rays. Multiple approaches for beam penetration including collection, tangential, and normal to the layers, along with variations in collection parameters are compared for their ability to attain high-resolution XRD data from the internal layers. This study displays the ability to monitor in situ, the response of the internal layers within the TBC, while implementing a thermal gradient across the thickness of the coated sample. The thermal setup maintained coating surface temperatures in the range of operating conditions, while monitoring the substrate cooling, for a controlled thermal gradient. Through variation in measurement location and beam parameters, sufficient intensities are obtained from the internal layers which can be used for depth resolved strain measurements. Results are used to establish the various techniques for obtaining XRD measurements through multi-layered coating systems and their outcomes will pave the way towards goals in achieving realistic in situ testing of these coatings.

  3. Synchrotron X-ray measurement techniques for thermal barrier coated cylindrical samples under thermal gradients

    SciTech Connect

    Siddiqui, Sanna F.; Knipe, Kevin; Manero, Albert; Raghavan, Seetha; Meid, Carla; Wischek, Janine; Bartsch, Marion; Okasinski, John; Almer, Jonathan; Karlsson, Anette M.

    2013-08-15

    Measurement techniques to obtain accurate in situ synchrotron strain measurements of thermal barrier coating systems (TBCs) applied to hollow cylindrical specimens are presented in this work. The Electron Beam Physical Vapor Deposition coated specimens with internal cooling were designed to achieve realistic temperature gradients over the TBC coated material such as that occurring in the turbine blades of aeroengines. Effects of the circular cross section on the x-ray diffraction (XRD) measurements in the various layers, including the thermally grown oxide, are investigated using high-energy synchrotron x-rays. Multiple approaches for beam penetration including collection, tangential, and normal to the layers, along with variations in collection parameters are compared for their ability to attain high-resolution XRD data from the internal layers. This study displays the ability to monitor in situ, the response of the internal layers within the TBC, while implementing a thermal gradient across the thickness of the coated sample. The thermal setup maintained coating surface temperatures in the range of operating conditions, while monitoring the substrate cooling, for a controlled thermal gradient. Through variation in measurement location and beam parameters, sufficient intensities are obtained from the internal layers which can be used for depth resolved strain measurements. Results are used to establish the various techniques for obtaining XRD measurements through multi-layered coating systems and their outcomes will pave the way towards goals in achieving realistic in situ testing of these coatings.

  4. Synchrotron X-ray CT characterization of friction-welded joints in tial turbocharger components

    NASA Astrophysics Data System (ADS)

    Sun, J. G.; Kropf, A. J.; Vissers, D. R.; Sun, W. M.; Katsoudas, J.; Yang, N.; Fei, D.

    2012-05-01

    Titanium aluminide (TiAl) is an advanced intermetallic material and is being investigated for application in turbocharger components for diesel engines. A TiAl turbocharger rotor consists of a cast TiAl turbine wheel and a Ti-alloy shaft that are joined by friction welding. Although friction welding is an established industrial process, it is still challenging to join dissimilar materials especially for brittle intermetallics. These joints are therefore required to be inspected using a nondestructive evaluation (NDE) method. In this study, synchrotron X-ray computed tomography (CT) developed at the Advanced Photon Source at Argonne National Laboratory was used for NDE characterization of friction-welded joint in three TiAl turbocharger rotors. The filtered synchrotron X-ray source has high peak energies to penetrate thick metallic materials, and the detector (imager) has high spatial resolutions to resolve small flaws. The CT inspections revealed detailed 3D crack distributions within poorly welded joints. The crack detection sensitivity and resolution was calibrated and found to be correlated well with destructive examination.

  5. STELLAR WIND INDUCED SOFT X-RAY EMISSION FROM CLOSE-IN EXOPLANETS

    SciTech Connect

    Kislyakova, K. G.; Lammer, H.; Fossati, L.; Johnstone, C. P.; Holmström, M.; Zaitsev, V. V.

    2015-01-30

    In this Letter, we estimate the X-ray emission from close-in exoplanets. We show that the Solar/Stellar Wind Charge Exchange Mechanism (SWCX), which produces soft X-ray emission, is very effective for hot Jupiters. In this mechanism, X-ray photons are emitted as a result of the charge exchange between heavy ions in the solar wind and the atmospheric neutral particles. In the solar system, comets produce X-rays mostly through the SWCX mechanism, but it has also been shown to operate in the heliosphere, in the terrestrial magnetosheath, and on Mars, Venus, and the Moon. Since the number of emitted photons is proportional to the solar wind mass flux, this mechanism is not very effective for the solar system giants. Here we present a simple estimate of the X-ray emission intensity that can be produced by close-in extrasolar giant planets due to charge exchange with the heavy ions of the stellar wind. Using the example of HD 209458b, we show that this mechanism alone can be responsible for an X-ray emission of ≈10{sup 22} erg s{sup –1}, which is 10{sup 6} times stronger than the emission from the Jovian aurora. We discuss also the possibility of observing the predicted soft X-ray flux of hot Jupiters and show that despite high emission intensities they are unobservable with current facilities.

  6. X-ray dense cellular inclusions in the cells of the green alga Chlamydomonas reinhardtii as seen by soft-x-ray microscopy

    SciTech Connect

    Stead, A.D.; Ford, T.W.; Page, A.M.; Brown, J.T.; Meyer-Ilse, W.

    1997-04-01

    Soft x-rays, having a greater ability to penetrate biological material than electrons, have the potential for producing images of intact, living cells. In addition, by using the so-called {open_quotes}water window{close_quotes} area of the soft x-ray spectrum, a degree of natural contrast is introduced into the image due to differential absorption of the wavelengths by compounds with a high carbon content compared to those with a greater oxygen content. The variation in carbon concentration throughout a cell therefore generates an image which is dependent upon the carbon density within the specimen. Using soft x-ray contact microscopy the authors have previously examined the green alga Chlamydomonas reinhardtii, and the most prominent feature of the cells are the numerous x-ray absorbing spheres, But they were not seen by conventional transmission electron microscopy. Similar structures have also been reported by the Goettingen group using their cryo transmission x-ray microscope at BESSY. Despite the fact that these spheres appear to occupy up to 20% or more of the cell volume when seen by x-ray microscopy, they are not visible by transmission electron microscopy. Given the difficulties and criticisms associated with soft x-ray contact microscopy, the present study was aimed at confirming the existence of these cellular inclusions and learning more of their possible chemical composition.

  7. Imaging of lateral spin valves with soft x-ray microscopy

    SciTech Connect

    Mosendz, O.; Mihajlovic, G.; Pearson, J. E.; Fischer, P.; Im, M.-Y.; Bader, S. D.; Hoffmann, A.

    2009-05-01

    We investigated Co/Cu lateral spin valves by means of high-resolution transmission soft x-ray microscopy with magnetic contrast that utilizes x-ray magnetic circular dichroism (XMCD). No magnetic XMCD contrast was observed at the Cu L{sub 3} absorption edge, which should directly image the spin accumulation in Cu. Although electrical transport measurements in a non-local geometry clearly detected the spin accumulation in Cu, which remained unchanged during illumination with circular polarized x-rays at the Co and Cu L{sub 3} absorption edges.

  8. The soft X-ray telescope for the SOLAR-A mission

    NASA Technical Reports Server (NTRS)

    Tsuneta, S.; Acton, L.; Bruner, M.; Lemen, J.; Brown, W.; Caravalho, R.; Catura, R.; Freeland, S.; Jurcevich, B.; Owens, J.

    1991-01-01

    The Soft X-ray Telescope (SXT) of the SOLAR-A mission is designed to produce X-ray movies of flares with excellent angular and time resolution as well as full-disk X-ray images for general studies. A selection of thin metal filters provide a measure of temperature discrimination and aid in obtaining the wide dynamic range required for solar observing. The co-aligned SXT aspect telescope will yield optical images for aspect reference, white-light flare and sunspot studies, and, possibly, helioseismology. This paper describes the capabilities and characteristics of the SXT for scientific observing.

  9. Calibration of a high resolution grating soft x-ray spectrometer.

    PubMed

    Magee, E W; Dunn, J; Brown, G V; Cone, K V; Park, J; Porter, F S; Kilbourne, C A; Kelley, R L; Beiersdorfer, P

    2010-10-01

    The calibration of the soft x-ray spectral response of a large radius of curvature, high resolution grating spectrometer (HRGS) with a back-illuminated charge-coupled device detector is reported. The instrument is cross-calibrated for the 10-50 Å waveband at the Lawrence Livermore National Laboratory electron beam ion trap (EBIT) x-ray source with the EBIT calorimeter spectrometer. The HRGS instrument is designed for laser-produced plasma experiments and is important for making high dynamic range measurements of line intensities, line shapes, and x-ray sources.

  10. Anti-contamination device for cryogenic soft X-ray diffraction microscopy

    DOE PAGES

    Huang, Xiaojing; Miao, Huijie; Nelson, Johanna; ...

    2011-05-01

    Cryogenic microscopy allows one to view frozen hydrated biological and soft matter specimens with good structural preservation and a high degree of stability against radiation damage. We describe a liquid nitrogen-cooled anti-contamination device for cryogenic X-ray diffraction microscopy. The anti-contaminator greatly reduces the buildup of ice layers on the specimen due to condensation of residual water vapor in the experimental vacuum chamber. We show by coherent X-ray diffraction measurements that this leads to fivefold reduction of background scattering, which is important for far-field X-ray diffraction microscopy of biological specimens.

  11. Ultra soft X-ray Microbeam: optical analysis and intensity measurements

    NASA Astrophysics Data System (ADS)

    Emilio, M. Di Paolo; Palladino, L.; Del Grande, F.

    2016-06-01

    In this work, optical analysis and intensity measurements of the Ultra Soft x-ray microbeam (100 eV-1 keV) are presented. X-ray emission at 500 eV are generated from a plasma produced by focusing Nd-YAG laser beam on the Yttrium target. In particular, we will report the study of x-ray intensity and the measurement of focal spot dimension. Moreover, the software/hardware control of sample holder position and the alignment of biological sample to the microbeam will be described.

  12. Anti-contamination device for cryogenic soft X-ray diffraction microscopy

    PubMed Central

    Huang, Xiaojing; Miao, Huijie; Nelson, Johanna; Turner, Joshua; Steinbrener, Jan; Shapiro, David; Kirz, Janos; Jacobsen, Chris

    2011-01-01

    Cryogenic microscopy allows one to view frozen hydrated biological and soft matter specimens with good structural preservation and a high degree of stability against radiation damage. We describe a liquid nitrogen-cooled anti-contamination device for cryogenic X-ray diffraction microscopy. The anti-contaminator greatly reduces the buildup of ice layers on the specimen due to condensation of residual water vapor in the experimental vacuum chamber. We show by coherent X-ray diffraction measurements that this leads to fivefold reduction of background scattering, which is important for far-field X-ray diffraction microscopy of biological specimens. PMID:21547016

  13. X-ray beam/biomaterial thermal interactions in third-generation synchrotron sources.

    PubMed

    Kuzay, T M; Kazmierczak, M; Hsieh, B J

    2001-01-01

    Third-generation synchrotron sources generate strong X-ray beams. The beam's interaction with biomaterials gives rise to concerns related to thermal damage and radiation damage. Of the two issues, the thermal interaction is conducive to rigorous analysis from first principles, although this has not been performed to date in a comprehensive manner. In this study, the interaction of the X-ray beam emanating from a third-generation synchrotron with a typical frozen biocrystal is theoretically studied, focusing specifically on the resulting unsteady (time-dependent) and steady heat-transfer phenomena. A unique regime map is developed to explain and to identify, on the basis of Fourier and Biot numbers as governing parameters, the applicable mathematical models that predict the subsequent thermal behavior. Depending on the values of these parameters, some simplified but realistic 'generic' solutions are generated that are suitable for that particular domain of applicability. Classical heat-transfer theory was used to describe the third-generation X-ray beam and biomaterial thermal interaction. Besides the generalized approach presented, numerous illustrative cases were solved and the resulting temperature levels are explicitly presented. Overall, the resulting thermal behavior of the system, i.e. peak and local temperature distribution, during both early transient development and for sustained long-time steady-state conditions, depends on a number of factors including the amount of energy absorbed, convective heat-transfer film coefficient and gas temperature, the sample size and shape, and the thermophysical properties of the sample and cooling gas. Results of the analysis revealed the strong influence that convection has on the transient and final steady-state temperature of the sample and the impact of internal heat conduction. The characteristic timescales of the important and dominant thermal processes with respect to the two types of thermal models are clearly

  14. X-ray Spectroscopy and Diffraction at HPCAT - An Integrated High Pressure Synchrotron Facility

    NASA Astrophysics Data System (ADS)

    Mao, H.; Hemley, R. J.; Hausermann, D.; Hu, M.; Meng, Y.; Somayazulu, M.

    2002-05-01

    High Pressure Collaborative Access Team (HPCAT) is a new facility dedicated for high-pressure research using the high-energy synchrotron beams at the Advanced Photon Source for in-situ investigations of crystallographic, elastic, rheologic, electronic, and magnetic properties of solids, liquids, and amorphous materials at high P and simultaneous high T or cryogenic T. The HPCAT high-brilliance undulator beamline is optimized for a full range of high-pressure x-ray spectroscopy. For instance, nuclear resonant inelastic scattering measures phonon densities of state of Fe-containing samples that yield valuable information on acoustic wave velocity, elasticity, elastic anisotropy, and thermodynamic quantities (vibrational energy, heat capacity, entropy, Debye temperature, and Gr\\x81neisen parameter) of materials at high pressures. Nuclear resonant x-ray forward scattering measures M”ssbauer spectra in the time domain that yield information on magnetism, site occupancy, oxidation states, and the Lamb-M”ssbauer coefficient of Fe. Resonant inelastic x-ray scattering measures element-specific electronic transitions. The medium-resolution (10-100 meV) non-resonant x-ray inelastic scattering measures electronic energies and dispersions that yield information on plasmons, excitons, electronic band structures, and chemical bondings, and high-resolution (<10 meV) inelastic scattering measures phonon dispersions that yield information on acoustic wave velocity and elasticity as a function of crystallographic orientation. X-ray emission spectroscopy yields information on valence electrons and spin states of d-electrons. A diamond branch monochromator diverts a full-intensity undulator monochromatic beam at energies up to 35 keV for full-time x-ray diffraction studies of crystallography, phase transitions, and equations of state in a side station without affecting the simultaneous operation of the main undualtor beamline. The HPCAT bending-magnet beamline is divided into two

  15. Thickness variations along coronal loops observed by the Soft X-ray Telescope on Yohkoh

    NASA Technical Reports Server (NTRS)

    Klimchuk, James A.; Lemen, James R.; Feldman, Uri; Tsuneta, Saku; Uchida, Yutaka

    1992-01-01

    The paper presents preliminary results of an investigation of thickness variations along coronal loops observed with the Yohkoh Soft X-ray Telescope (SXT), using observations from ten loops selected from the SXT data. The quantitative results indicate that coronal X-ray loops do not expand. This contradicts the expectation that, if plasma loops coincide with magnetic loops, many loops must be significantly broader at their tops than at their foot points. Possible interpretations of the obtained results are proposed.

  16. The Soft X-ray research instrument at the Linac Coherent Light Source

    DOE PAGES

    Dakovski, Georgi L.; Heimann, Philip; Holmes, Michael; ...

    2015-04-02

    The Soft X-ray Research instrument provides intense ultrashort X-ray pulses in the energy range 280–2000 eV. A diverse set of experimental stations may be installed to investigate a broad range of scientific topics such as ultrafast chemistry, highly correlated materials, magnetism, surface science, and matter under extreme conditions. A brief description of the main instrument components will be given, followed by some selected scientific highlights.

  17. Emission Line Spectra in the Soft X-ray Region 20 - 75 Angstroms

    NASA Technical Reports Server (NTRS)

    Lepson, J. K.; Beiersdorfer, P.; Chen, H.; Behar, E.; Kahn, S. M.

    2002-01-01

    As part of a project to complete a comprehensive catalogue of astrophysically relevant emission lines in support of new-generation X-ray observatories using the Lawrence Livermore electron beam ion traps EBIT-I and EDIT-II, emission lines of argon and sulfur in the soft X-ray and extreme ultraviolet region were studied. Observations of Ar IX through Ar XVI and S VII through S XIV between 20 and 75 Angstrom are presented to illustrate our work.

  18. Assessment of surface roughness by use of soft x-ray scattering

    NASA Astrophysics Data System (ADS)

    Meng, Yan-li; Wang, Yong-gang; Chen, Shu-yan; Chen, Bo

    2009-08-01

    A soft x-ray reflectometer with laser produced plasma source has been designed, which can work from wavelength 8nm to 30 nm and has high performance. Using the soft x-ray reflectometer above, the scattering light distribution of silicon and zerodur mirrors which have super-smooth surfaces could be measured at different incidence angle and different wavelength. The measurement when the incidence angle is 2 degree and the wavelength is 11nm has been given in this paper. A surface scattering theory of soft x-ray grazing incidence optics based on linear system theory and an inverse scattering mathematical model is introduced. The vector scattering theory of soft x-ray scattering also is stated in detail. The scattering data are analyzed by both the methods above respectively to give information about the surface profiles. On the other hand, both the two samples are measured by WYKO surface profiler, and the surface roughness of the silicon and zerodur mirror is 1.3 nm and 1.5nm respectively. The calculated results are in quantitative agreement with those measured by WYKO surface profiler, which indicates that soft x-ray scattering is a very useful tool for the evaluation of highly polished surfaces. But there still some difference among the results of different theory and WYKO, and the possible reasons of such difference have been discussed in detail.

  19. Soft X-ray imaging techniques for calculating the Earth's dayside boundaries

    NASA Astrophysics Data System (ADS)

    Connor, Hyunju; Kuntz, Kip; Sibeck, David; Collier, Michael; Aryan, Homayon; Branduardi-Raymont, Graziella; Collado-Vega, Yaireska; Porter, Frederick; Purucker, Michael; Snowden, Steven; Raeder, Joachim; Thomas, Nicholas; Walsh, Brian

    2016-04-01

    Charged particles and neutral atoms exchange electrons in many space plasma venues. Soft X-rays are emitted when highly charged solar wind ions, such as C6+. O7+, and Fe13+, interact with Hydrogen and Helium atoms. Soft X-ray images can be a powerful technique to remotely probe the plasma and neutral density structures created when the solar wind interacts with planetary exospheres, such as those at the Earth, Moon, Mars, Venus, and comets. The recently selected ESA-China joint spacecraft mission, "Solar wind - Magnetosphere - Ionosphere Link Explorer (SMILE)" will have a soft X-ray imager on board and provide pictures of the Earth's dayside system after its launch in 2021. In preparation for this future mission, we simulate soft X-ray images of the Earth's dayside system, using the OpenGGCM global magnetosphere MHD model and the Hodges model of the Earth's exosphere. Then, we discuss techniques to determine the location of the Earth's dayside boundaries (bow shock and magnetopause) from the soft X-ray images.

  20. Technological aspects of GEM detector design and assembling for soft x-ray application

    NASA Astrophysics Data System (ADS)

    Kowalska-Strzeciwilk, E.; Chernyshova, M.

    2016-09-01

    Various types of Micro Pattern Gas Detectors (MPGDs) found applications as tracking detectors in high energy particle physics experiments and as well as imaging detectors, especially for soft X-rays. These detectors offer several advantages like high count rate capability, good spatial and energy resolution, low cost and possibility of constructing large area detectors with very small dead area. Construction, like the triple Gas Electron Multiplier (GEM) detector has become a standard detector, which is widely used for different imaging applications. Some examples of such applications are: monitoring the impurity in plasma, imaging system for mapping of some parameters like pigment distributions using X-ray fluorescence technique[1], proton range radiography system for quality assurance in hadron therapy. Measuring of the Soft X-Ray (SXR) radiation of magnetic fusion plasma is a standard way of accessing valuable information, for example, about particle transport and MHD. The paper is focused on the design of GEM based soft Xray radiation detecting system which is under development. It is dedicated to study soft X-ray emission of plasma radiation with focus on tungsten emission lines energy region. The paper presents the designing, construction and assembling of a prototype of two triple-GEM detectors for soft-X ray application on the WEST device.