Sample records for angle x-ray scattering

  1. Small Angle X-Ray Scattering Detector

    DOE Patents [OSTI]

    Hessler, Jan P.

    2004-06-15T23:59:59.000Z

    A detector for time-resolved small-angle x-ray scattering includes a nearly constant diameter, evacuated linear tube having an end plate detector with a first fluorescent screen and concentric rings of first fiber optic bundles for low angle scattering detection and an annular detector having a second fluorescent screen and second fiber optic bundles concentrically disposed about the tube for higher angle scattering detection. With the scattering source, i.e., the specimen under investigation, located outside of the evacuated tube on the tube's longitudinal axis, scattered x-rays are detected by the fiber optic bundles, to each of which is coupled a respective photodetector, to provide a measurement resolution, i.e., dq/q, where q is the momentum transferred from an incident x-ray to an x-ray scattering specimen, of 2% over two (2) orders of magnitude in reciprocal space, i.e., qmax/qmin approx=lO0.

  2. Small Angle X-ray Scattering (SAXS) Laboratory Learning Experiences

    E-Print Network [OSTI]

    Meagher, Mary

    .A. & Svergun D.I. (1987). Structure Analysis by Small-Angle X-Ray and Neutron Scattering. NY: Plenum PressSmall Angle X-ray Scattering (SAXS) Laboratory Learning Experiences o - Use of small angle X-ray scattering instrumentation o - Programs that you will use SAXS (BRUKER AXS) PRIMUS (Konarev, Volkov, Koch

  3. Small Angle X-ray Scattering

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our Instagram Secretary Moniz9Morgan ManagingW.tepidumAngle X-ray Scattering

  4. Micellar structure from comparison of X-ray and neutron small-angle scattering

    E-Print Network [OSTI]

    Boyer, Edmond

    249 Micellar structure from comparison of X-ray and neutron small-angle scattering T. Zemb and P according to the method developed by Hayter and Penfold. Both X-ray and neutron scattering signals, or by a combination of both. It has been shown recent- ly [1, 2] that it is possible in neutron scattering studies

  5. X-ray small-angle scattering from sputtered CeO{sub 2}/C bilayers

    SciTech Connect (OSTI)

    Haviar, S.; Dubau, M.; Khalakhan, I.; Vorokhta, M.; Matolinova, I.; Matolin, V. [Department of Surface and Plasma Science, Faculty of Mathematics and Physics Charles University, V Holesovickach 2, 180 00, Prague 8 (Czech Republic); Vales, V.; Endres, J.; Holy, V. [Department of Condensed Matter Physics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, 121 16 Prague 2 (Czech Republic); Buljan, M. [Institute Ruder Boskovic, Bijenicka 54, 10000 Zagreb (Croatia); Bernstorff, S. [Sincrotrone ELETTRA, 34149 Basovizza, Trieste (Italy)

    2013-01-14T23:59:59.000Z

    Surface and interface morphology of cerium oxide/carbon bilayers used as thin-film catalysts is studied by grazing-incidence small-angle x-ray scattering, scanning electron microscopy, and atomic-force microscopy, and the dependence of the structural parameters on the thicknesses of the constituting layers is investigated. The applicability of x-ray scattering and its advantages over standard analytical methods are discussed.

  6. X-ray crystal structure and small-angle X-ray scattering of sheep liver sorbitol dehydrogenase

    SciTech Connect (OSTI)

    Yennawar, Hemant [Pennsylvania State University, 8 Althouse Laboratory, University Park, PA 16802 (United States); Møller, Magda [Cornell High Energy Synchrotron Source, Ithaca, NY 14853 (United States); University of Copenhagen, DK-2100 Copenhagen (Denmark); Gillilan, Richard [Cornell High Energy Synchrotron Source, Ithaca, NY 14853 (United States); Yennawar, Neela, E-mail: nhy1@psu.edu [Pennsylvania State University, 8 Althouse Laboratory, University Park, PA 16802 (United States)

    2011-05-01T23:59:59.000Z

    The X-ray crystal structure and a small-angle X-ray scattering solution structure of sheep liver sorbitol dehydrogenase have been determined. The details of the interactions that enable the tetramer scaffold to be the functional biological unit have been analyzed. The X-ray crystal structure of sheep liver sorbitol dehydrogenase (slSDH) has been determined using the crystal structure of human sorbitol dehydrogenase (hSDH) as a molecular-replacement model. slSDH crystallized in space group I222 with one monomer in the asymmetric unit. A conserved tetramer that superposes well with that seen in hSDH (despite belonging to a different space group) and obeying the 222 crystal symmetry is seen in slSDH. An acetate molecule is bound in the active site, coordinating to the active-site zinc through a water molecule. Glycerol, a substrate of slSDH, also occupies the substrate-binding pocket together with the acetate designed by nature to fit large polyol substrates. The substrate-binding pocket is seen to be in close proximity to the tetramer interface, which explains the need for the structural integrity of the tetramer for enzyme activity. Small-angle X-ray scattering was also used to identify the quaternary structure of the tetramer of slSDH in solution.

  7. Small angle X-ray scattering study of coal soot formation

    SciTech Connect (OSTI)

    Winans, R. E.; Parker, J. T.; Seifert, S.; Fletcher, T. H.

    2000-02-14T23:59:59.000Z

    The objective of this study is to examine, by small angle X-ray scattering (SAXS), the formation of soot from individual coal particle combustion in a methane flat flame burner. The SAXS instrument at the Basic Energy Sciences Synchrotron Radiation Center (BESSRC) at the Advanced Photon Source (APS) can be used to observe both the formation of spherules and clusters since it can access length scales of 6--6000 {angstrom}. The high X-ray flux enables rapid acquisition of scattering data of various regions of the flame. SAXS data reveal particle size, shape, surface areas, and surface roughness.

  8. Characterization of irradiation-induced precipitates by small angle x-ray and neutron scattering experiments

    SciTech Connect (OSTI)

    Grosse, M.; Eichhorn, F.; Boehmert, J.; Brauer, G. [Research Center Rossendorf Inc., Dresden (Germany)

    1996-12-31T23:59:59.000Z

    The nature of the irradiation-induced precipitates in the VVER-440-type steel 15Kh2MFA has been investigated by the combination of small angle neutron scattering and anomalous small angle X-ray scattering. Information about the chemical composition of the irradiation-induced precipitates was obtained by the method of contrast variation. ASAXS experiments with variation of the X-ray energy near the energy of the vanadium K-absorption edge prove the content of vanadium within the irradiation-induced precipitates. The scattering density of the precipitates is lower than the scattering density of the iron matrix. The chemical shift of the vanadium-K{sub {alpha}}-absorption-edge and the results of the variation of the contribution of the magnetic scattering in the SANS experiment show, that vanadium does not precipitate in an elementary state. These results can be explained by assuming the precipitates are vanadium carbide.

  9. BIOISIS: Biological Macromolecules by Small Angle X-ray Scattering (SAXS)

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Tainer, John (Scripps Research Institute); Hura, Greg (LBNL); Rambo, Robert P. (LBNL)

    BIOISIS is an open access database dedicated to the study of biological macromolecules by small angle X-ray scattering (SAXS). BIOISIS aims to become the complete source for the deposition, distribution and maintenance of small angle X-ray scattering data and technologies. The database is designed around the concept of an ôexperimentö and relates a specific experiment to a set of genes, organisms, computational models and experimental data. As of May 2012, BIOSIS contains 7,118 genes covering four different organisms. Forty-two modeled structures are available. Clicking on a structures reveals scattering curves, experimental conditions, and experimental values. The data are collected at Beamline 12.3.1 of the Advanced Light Source (ALS).[Copied with editing from http://www.bioisis.net/about

  10. Wide angle x-ray scattering of proteins : effect of beam exposure on protein integrity.

    SciTech Connect (OSTI)

    Fischetti, R. F.; Rodi, D. J.; Mirza, A.; Makowski, L.; Illinois Inst. of Tech.

    2003-01-01T23:59:59.000Z

    Wide-angle X-ray scattering patterns from proteins in solution contain information relevant to the determination of protein fold. At relevant scattering angles, however, these data are weak, and the degree to which they might be used to categorize the fold of a protein is unknown. Preliminary work has been performed at the BioCAT insertion-device beamline at the Advanced Photon Source which demonstrates that one can collect X-ray scattering data from proteins in solution to spacings of at least 2.2 {angstrom} (q = 2.8 {angstrom}-1). These data are sensitive to protein conformational states, and are in good agreement with the scattering predicted by the program CRYSOL using the known three-dimensional atomic coordinates of the protein. An important issue in the exploitation of this technique as a tool for structural genomics is the extent to which the high intensity of X-rays available at third-generation synchrotron sources chemically or structurally damage proteins. Various data-collection protocols have been investigated demonstrating conditions under which structural degradation of even sensitive proteins can be minimized, making this technique a viable tool for protein fold categorization, the study of protein folding, unfolding, protein-ligand interactions and domain movement.

  11. Characterization of porous materials using combined small-angle X-ray and neutron scattering techniques

    SciTech Connect (OSTI)

    Hu, Naiping; Borkar, Neha; Kohls, Doug; Schaefer, Dale W. (UCIN)

    2014-09-24T23:59:59.000Z

    A combination of ultra small angle X-ray scattering (USAXS) and ultra small angle neutron scattering (USANS) is used to characterize porous materials. The analysis methods yield quantitative information, including the mean skeletal chord length, mean pore chord length, skeletal density, and composition. A mixed cellulose ester (MCE) membrane with a manufacturer-labeled pore size of 0.1 {mu}m was used as a model to elucidate the specifics of the method. Four approaches describing four specific scenarios (different known parameters and form of the scattering data) are compared. Pore chords determined using all four approaches are in good agreement with the scanning electron microscopy estimates but are larger than the manufacturer's nominal pore size. Our approach also gives the average chord of the skeletal solid (struts) of the membrane, which is also consistent for all four approaches. Combined data from USAXS and USANS gives the skeletal density and the strut composition.

  12. Time Resolved Collapse of a Folding Protein Observed with Small Angle X-Ray Scattering

    SciTech Connect (OSTI)

    Pollack, L.; Tate, M. W.; Finnefrock, A. C.; Kalidas, C.; Trotter, S.; Darnton, N. C.; Lurio, L.; Austin, R. H.; Batt, C. A.; Gruner, S. M. (and others)

    2001-05-21T23:59:59.000Z

    High-intensity, ''pink'' beam from an undulator was used in conjunction with microfabricated rapid-fluid mixing devices to monitor the early events in protein folding with time resolved small angle x-ray scattering. This Letter describes recent work on the protein bovine {beta} -lactoglobulin where collapse from an expanded to a compact set of states was directly observed on the millisecond time scale. The role of chain collapse, one of the initial stages of protein folding, is not currently understood. The characterization of transient, compact states is vital in assessing the validity of theories and models of the folding process.

  13. The accurate assessment of small-angle X-ray scattering data

    SciTech Connect (OSTI)

    Grant, Thomas D. [Hauptman–Woodward Medical Research Institute, 700 Ellicott Street, Buffalo, NY 14203 (United States); Luft, Joseph R. [Hauptman–Woodward Medical Research Institute, 700 Ellicott Street, Buffalo, NY 14203 (United States); SUNY Buffalo, 700 Ellicott Street, Buffalo, NY 14203 (United States); Carter, Lester G.; Matsui, Tsutomu; Weiss, Thomas M.; Martel, Anne [Stanford Synchrotron Radiation Lightsource, 2575 Sand Hill Road, MS69, Menlo Park, CA 94025 (United States); Snell, Edward H., E-mail: esnell@hwi.buffalo.edu [Hauptman–Woodward Medical Research Institute, 700 Ellicott Street, Buffalo, NY 14203 (United States); SUNY Buffalo, 700 Ellicott Street, Buffalo, NY 14203 (United States)

    2015-01-01T23:59:59.000Z

    A set of quantitative techniques is suggested for assessing SAXS data quality. These are applied in the form of a script, SAXStats, to a test set of 27 proteins, showing that these techniques are more sensitive than manual assessment of data quality. Small-angle X-ray scattering (SAXS) has grown in popularity in recent times with the advent of bright synchrotron X-ray sources, powerful computational resources and algorithms enabling the calculation of increasingly complex models. However, the lack of standardized data-quality metrics presents difficulties for the growing user community in accurately assessing the quality of experimental SAXS data. Here, a series of metrics to quantitatively describe SAXS data in an objective manner using statistical evaluations are defined. These metrics are applied to identify the effects of radiation damage, concentration dependence and interparticle interactions on SAXS data from a set of 27 previously described targets for which high-resolution structures have been determined via X-ray crystallography or nuclear magnetic resonance (NMR) spectroscopy. The studies show that these metrics are sufficient to characterize SAXS data quality on a small sample set with statistical rigor and sensitivity similar to or better than manual analysis. The development of data-quality analysis strategies such as these initial efforts is needed to enable the accurate and unbiased assessment of SAXS data quality.

  14. Eur. J. Biochem. 85, 529-534 (1978) X-Ray and Neutron Small-Angle Scattering Studies

    E-Print Network [OSTI]

    1978-01-01T23:59:59.000Z

    Eur. J. Biochem. 85, 529-534 (1978) X-Ray and Neutron Small-Angle Scattering Studies of the Complex-ray and neutron scattering techniques. In this work, we concentrated mainly on radius of gyration analyses and a neutron scattering experiment is performed in 21-Iz0 solvent. This decrease simply reflects the fact

  15. Robust, high-throughput solution structural analyses by small angle X-ray scattering (SAXS)

    SciTech Connect (OSTI)

    Hura, Greg L.; Menon, Angeli L.; Hammel, Michal; Rambo, Robert P.; Poole II, Farris L.; Tsutakawa, Susan E.; Jenney Jr, Francis E.; Classen, Scott; Frankel, Kenneth A.; Hopkins, Robert C.; Yang, Sungjae; Scott, Joseph W.; Dillard, Bret D.; Adams, Michael W. W.; Tainer, John A.

    2009-07-20T23:59:59.000Z

    We present an efficient pipeline enabling high-throughput analysis of protein structure in solution with small angle X-ray scattering (SAXS). Our SAXS pipeline combines automated sample handling of microliter volumes, temperature and anaerobic control, rapid data collection and data analysis, and couples structural analysis with automated archiving. We subjected 50 representative proteins, mostly from Pyrococcus furiosus, to this pipeline and found that 30 were multimeric structures in solution. SAXS analysis allowed us to distinguish aggregated and unfolded proteins, define global structural parameters and oligomeric states for most samples, identify shapes and similar structures for 25 unknown structures, and determine envelopes for 41 proteins. We believe that high-throughput SAXS is an enabling technology that may change the way that structural genomics research is done.

  16. Small angle neutron and X-ray scattering studies of carbons prepared using inorganic templates

    SciTech Connect (OSTI)

    Sandi, G.; Thiyagarajan, P.; Winans, R.E.; Carrado, K.A.

    1997-09-01T23:59:59.000Z

    Small angle neutron (SANS) and X-ray (SAXS) scattering analyses of carbons derived from organic-loaded inorganic template materials, used as anodes in lithium ion cells, have been performed. Two clays were used as templates to load the organic precursors, pillared montmorrillonite (PILC), a layered silicate clay whose sheets have been permanently propped open by sets of thermally stable molecular props, and sepiolite, a natural channeled clay. Five different organic precursors were used to load the PILC: pyrene, styrene, pyrene/trioxane copolymer, ethylene and propylene, whereas only propylene and ethylene were used to load sepiolite. Pyrolysis took place at 700{degrees}C under nitrogen. Values such as hole radius, fractal dimension, cutoff length and density of the final carbons will be compared as a function of the clay and carbon precursors.

  17. Studies of protein structure in solution and protein folding using synchrotron small-angle x-ray scattering

    SciTech Connect (OSTI)

    Chen, Lingling

    1996-04-01T23:59:59.000Z

    Synchrotron small angle x-ray scattering (SAXS) has been applied to the structural study of several biological systems, including the nitrogenase complex, the heat shock cognate protein (hsc70), and lysozyme folding. The structural information revealed from the SAXS experiments is complementary to information obtained by other physical and biochemical methods, and adds to our knowledge and understanding of these systems.

  18. X-ray Dust Scattering at Small Angles: The Complete Halo around GX13+1

    E-Print Network [OSTI]

    Randall K. Smith

    2008-05-04T23:59:59.000Z

    The exquisite angular resolution available with Chandra should allow precision measurements of faint diffuse emission surrounding bright sources, such as the X-ray scattering halos created by interstellar dust. However, the ACIS CCDs suffer from pileup when observing bright sources, and this creates difficulties when trying to extract the scattered halo near the source. The initial study of the X-ray halo around GX13+1 using only the ACIS-I detector done by Smith, Edgar & Shafer (2002) suffered from a lack of sensitivity within 50'' of the source, limiting what conclusions could be drawn. To address this problem, observations of GX13+1 were obtained with the Chandra HRC-I and simultaneously with the RXTE PCA. Combined with the existing ACIS-I data, this allowed measurements of the X-ray halo between 2-1000''. After considering a range of dust models, each assumed to be smoothly distributed with or without a dense cloud along the line of sight, the results show that there is no evidence in this data for a dense cloud near the source, as suggested by Xiang et al. (2005). Finally, although no model leads to formally acceptable results, the Weingartner & Draine (2001) and nearly all of the composite grain models from Zubko, Dwek & Arendt (2004) give poor fits.

  19. Anomalous small angle x-ray scattering studies of amorphous metal-germanium alloys

    SciTech Connect (OSTI)

    Rice, M.

    1993-12-01T23:59:59.000Z

    This dissertation addresses the issue of composition modulation in sputtered amorphous metal-germanium thin films with the aim of understanding the intermediate range structure of these films as a function of composition. The investigative tool used in this work is anomalous small-angle X-ray scattering (ASAXS). The primary focus of this investigation is the amorphous iron-germanium (a-Fe{sub x}Ge{sub 100-x}) system with particular emphasis on the semiconductor-rich regime. Brief excursions are made into the amorphous tungsten-germanium (a-W{sub x}Ge{sub 100-x}) and the amorphous molybdenum-germanium (a-Mo{sub x}Ge{sub 100-x}) systems. All three systems exhibit an amorphous structure over a broad composition range extending from pure amorphous germanium to approximately 70 atomic percent metal when prepared as sputtered films. Across this composition range the structures change from the open, covalently bonded, tetrahedral network of pure a-Ge to densely packed metals. The structural changes are accompanied by a semiconductor-metal transition in all three systems as well as a ferromagnetic transition in the a-Fe{sub x}Ge{sub 100-x} system and a superconducting transition in the a-Mo{sub x}Ge{sub 100-x} system. A long standing question, particularly in the a-Fe{sub x}Ge{sub 100-x} and the a-Mo{sub x}Ge{sub 100-x} systems, has been whether the structural changes (and therefore the accompanying electrical and magnetic transitions) are accomplished by homogeneous alloy formation or phase separation. The application of ASAXS to this problem proves unambiguously that fine scale composition modulations, as distinct from the simple density fluctuations that arise from cracks and voids, are present in the a-Fe{sub x}Ge{sub 100-x}, a-W{sub x}Ge{sub 100-x}, and a-Mo{sub x}Ge{sub 100-x} systems in the semiconductor-metal transition region. Furthermore, ASAXS shows that germanium is distributed uniformly throughout each sample in the x<25 regime of all three systems.

  20. Accurate small and wide angle x-ray scattering profiles from atomic models of proteins and nucleic acids

    SciTech Connect (OSTI)

    Nguyen, Hung T. [BioMaPS Institute for Quantitative Biology, Rutgers University, Piscataway, New Jersey 08854 (United States); Pabit, Suzette A.; Meisburger, Steve P.; Pollack, Lois [School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853 (United States); Case, David A., E-mail: case@biomaps.rutgers.edu [BioMaPS Institute for Quantitative Biology, Rutgers University, Piscataway, New Jersey 08854 (United States); Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854 (United States)

    2014-12-14T23:59:59.000Z

    A new method is introduced to compute X-ray solution scattering profiles from atomic models of macromolecules. The three-dimensional version of the Reference Interaction Site Model (RISM) from liquid-state statistical mechanics is employed to compute the solvent distribution around the solute, including both water and ions. X-ray scattering profiles are computed from this distribution together with the solute geometry. We describe an efficient procedure for performing this calculation employing a Lebedev grid for the angular averaging. The intensity profiles (which involve no adjustable parameters) match experiment and molecular dynamics simulations up to wide angle for two proteins (lysozyme and myoglobin) in water, as well as the small-angle profiles for a dozen biomolecules taken from the BioIsis.net database. The RISM model is especially well-suited for studies of nucleic acids in salt solution. Use of fiber-diffraction models for the structure of duplex DNA in solution yields close agreement with the observed scattering profiles in both the small and wide angle scattering (SAXS and WAXS) regimes. In addition, computed profiles of anomalous SAXS signals (for Rb{sup +} and Sr{sup 2+}) emphasize the ionic contribution to scattering and are in reasonable agreement with experiment. In cases where an absolute calibration of the experimental data at q = 0 is available, one can extract a count of the excess number of waters and ions; computed values depend on the closure that is assumed in the solution of the Ornstein–Zernike equations, with results from the Kovalenko–Hirata closure being closest to experiment for the cases studied here.

  1. Small-angle x-ray scattering measurements of the microstructure of liquid helium mixtures adsorbed in aerogel

    SciTech Connect (OSTI)

    Lurio, L. B.; Mulders, N.; Paetkau, M.; Chan, M. H. W.; Mochrie, S. G. J. [Department of Physics, Northern Illinois University, DeKalb, Illinois 60115 (United States); Department of Physics, University of Delaware, Newark, Delaware 19716 (United States); Department of Physics and Astronomy, Okanagan College, British Columbia V1Y4X8 (Canada); Department of Physics, Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Department of Physics, Yale University, New Haven, Connecticut 06511 (United States)

    2007-07-15T23:59:59.000Z

    Small-angle x-ray scattering (SAXS) was used to measure the microstructure of isotopic mixtures of {sup 3}He and {sup 4}He adsorbed into silica aerogels as a function of temperature and {sup 3}He concentration. The SAXS measurements could be well described by the formation of a nearly pure film of {sup 4}He which separates from the bulk mixture onto the aerogel strands and which thickens with decreasing temperature. Previous observations of a superfluid {sup 3}He-rich phase are consistent with superfluidity existing within this film phase. Observed differences between different density aerogels are explained in terms of the depletion of {sup 4}He from the bulk mixture due to film formation.

  2. Monitoring simultaneously the growth of nanoparticles and aggregates by in situ ultra-small-angle x-ray scattering

    SciTech Connect (OSTI)

    Kammler, Hendrik K.; Beaucage, Gregory; Kohls, Douglas J.; Agashe, Nikhil; Ilavsky, Jan [Particle Technology Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, ML F23, CH-8092 Zurich (Switzerland); Department of Chemical and Materials Engineering, University of Cincinnati, 540 Engineering Research Center, Cincinnati, Ohio 45221-0012 (United States); UNICAT, Advanced Photon Source, Building 438D, 9700 South Cass Avenue, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

    2005-03-01T23:59:59.000Z

    Ultra-small-angle x-ray scattering can provide information about primary particles and aggregates from a single scattering experiment. This technique is applied in situ to flame aerosol reactors for monitoring simultaneously the primary particle and aggregate growth dynamics of oxide nanoparticles in a flame. This was enabled through the use of a third generation synchrotron source (Advanced Photon Source, Argonne IL, USA) using specialized scattering instrumentation at the UNICAT facility which is capable of simultaneously measuring nanoscales to microscales (1 nm to 1 {mu}m). More specifically, the evolution of primary-particle diameter, mass-fractal dimension, geometric standard deviation, silica volume fraction, number concentration, radius of gyration of the aggregate, and number of primary particles per aggregate are measured along the flame axis for two different premixed flames. All these particle characteristics were derived from a single and nonintrusive measurement technique. Flame temperature profiles were measured in the presence of particles by in situ Fourier transform infrared spectroscopy and thermophoretic sampling was used to visualize particle growth with height above the burner as well as in the radial direction.

  3. Structure of Flame-Made Silica Nanoparticles by Ultra-Small-Angle X-ray Scattering

    E-Print Network [OSTI]

    Beaucage, Gregory

    by thermophoretic sampling and microscopy that provided consistent results with light scattering with respect thermophoretically collected samples and image analysis of t

  4. Molecular structures of fluid phase phosphatidylglycerol bilayers as determined by small angle neutron and X-ray scattering

    E-Print Network [OSTI]

    Nagle, John F.

    neutron and X-ray scattering Jianjun Pan a, , Frederick A. Heberle a , Stephanie Tristram-Nagle b Matter Division, Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, TN 378316100 Institute for Neutron Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 378316453, USA e Canadian

  5. Protein Folding Dynamics Detected By Time-Resolved Synchrotron X-ray Small-Angle Scattering Technique

    SciTech Connect (OSTI)

    Fujisawa, Tetsuro; Takahashi, Satoshi [RIKEN Harima Institute, SPring-8 Center, Laboratory for Biometal Science, Hyogo 679-5148 (Japan); Institute for Protein Research, Osaka University Suita Osaka 565-0871/CREST, JST (Japan)

    2007-03-30T23:59:59.000Z

    The polypeptide collapse is an essential dynamics in protein folding. To understand the mechanism of the collapse, in situ observation of folding by various probes is necessary. The changes in secondary and tertiary structures in the folding process of globular proteins, whose chain lengths are less than 300 polypeptides, were observed by circular dichrosim and intrinsic fluorescence spectroscopies, respectively. On the other hand, those in protein compactness could be only detected by using time-resolved synchrotron x-ray small-angle scattering technique. The observed dynamics for several proteins with different topologies suggested a common folding mechanism termed 'collapse and search' dynamics, in which the polypeptide collapse precedes the formation of the native contact formation. In 'collapse and search' dynamics, the most outstanding feature lied in the compactness of the initial intermediates. The collapsed intermediates demonstrated the scaling relationship between radius of gyration (Rg) and chain length with a scaling exponent of 0.35 {+-} 0.11, which is close to the value (1/3) predicted by mechano-statistical theory for the collapsed globules of polymers in poor solvent. Thus, it was suggested that the initial collapse is caused by the coil-globule transition of polymers. Since the collapse is essential to the folding of larger proteins, further investigations on the collapse likely lead to an important insight into the protein folding phenomena.

  6. Mass fractal characteristics of wet sonogels as determined by small-angle x-ray scattering and differential scanning calorimetry

    SciTech Connect (OSTI)

    Vollet, D. R.; Donatti, D. A.; Ibanez Ruiz, A.; Gatto, F. R. [Departamento de Fisica, Unesp-Univerisdade Estadual Paulista, IGCE, P.O. Box 178 CEP 13500-970 Rio Claro, SP (Brazil)

    2006-07-01T23:59:59.000Z

    Low density silica sonogels were prepared from acid sonohydrolysis of tetraethoxysilane. Wet gels were studied by small-angle x-ray scattering (SAXS) and differential scanning calorimetry (DSC). The DSC tests were carried out under a heating rate of 2 deg. C/min from -120 deg. C up to 30 deg. C. Aerogels were obtained by CO{sub 2} supercritical extraction and characterized by nitrogen adsorption and SAXS. The DSC thermogram displays two distinct endothermic peaks. The first, a broad peak extending from about -80 deg. C up to practically 0 deg. C, was associated to the melting of ice nanocrystals with a crystal size distribution with 'pore' diameter ranging from 1 or 2 nm up to about 60 nm, as estimated from Thomson's equation. The second, a sharp peak with onset temperature close to 0 deg. C, was attributed to the melting of macroscopic crystals. The DSC incremental 'nanopore' volume distribution is in reasonable agreement with the incremental pore volume distribution of the aerogel as determined from nitrogen adsorption. No macroporosity was detected by nitrogen adsorption, probably because the adsorption method applies stress on the sample during measurement, leading to a underestimation of pore volume, or because often positive curvature of the solid surface is in aerogels, making the nitrogen condensation more difficult. According to the SAXS results, the solid network of the wet gels behaves as a mass fractal structure with mass fractal dimension D=2.20{+-}0.01 in a characteristic length scale below {xi}=7.9{+-}0.1 nm. The mass fractal characteristics of the wet gels have also been probed from DSC data by means of an earlier applied modeling for generation of a mass fractal from the incremental ''pore'' volume distribution curves. The results are shown to be in interesting agreement with the results from SAXS.

  7. Mass fractal characteristics of silica sonogels as determined by small-angle x-ray scattering and nitrogen adsorption

    SciTech Connect (OSTI)

    Donatti, D.A.; Vollet, D.R.; Ibanez Ruiz, A.; Mesquita, A.; Silva, T.F.P. [Unesp-Universidade Estadual Paulista, IGCE, Departamento de Fisica, P.O. Box 178 CEP, 13500-970 Rio Claro, Sao Paulo (Brazil)

    2005-01-01T23:59:59.000Z

    A sample series of silica sonogels was prepared using different water-tetraethoxysilane molar ratio (r{sub w}) in the gelation step of the process in order to obtain aerogels with different bulk densities after the supercritical drying. The samples were analyzed by means of small-angle x-ray-scattering (SAXS) and nitrogen-adsorption techniques. Wet sonogels exhibit mass fractal structure with fractal dimension D increasing from {approx}2.1 to {approx}2.4 and mass-fractal correlation length {xi} diminishing from {approx}13 nm to {approx}2 nm, as r{sub w} is changed in the nominal range from 66 to 6. The process of obtaining aerogels from sonogels and heat treatment at 500 deg. C, in general, increases the mass-fractal dimension D, diminishes the characteristic length {xi} of the fractal structure, and shortens the fractal range at the micropore side for the formation of a secondary structured particle, apparently evolved from the original wet structure at a high resolution level. The overall mass-fractal dimension D of aerogels was evaluated as {approx}2.4 and {approx}2.5, as determined from SAXS and from pore-size distribution by nitrogen adsorption, respectively. The fine structure of the 'secondary particle' developed in the obtaining of aerogels could be described as a surface-mass fractal, with the correlated surface and mass-fractal dimensions decreasing from {approx}2.4 to {approx}2.0 and from {approx}2.7 to {approx}2.5, respectively, as the aerogel bulk density increases from 0.25 (r{sub w}=66) up to 0.91 g/cm{sup 3} (r{sub w}=6)

  8. A promising concept for using near-surface measuring angles in angle-resolved x-ray photoelectron spectroscopy considering elastic scattering effects

    SciTech Connect (OSTI)

    Oswald, S.; Oswald, F. [IFW Dresden, Postfach 270116, D-01171 Dresden (Germany)

    2011-02-01T23:59:59.000Z

    The increasing number of applications of very thin films requires both reliable thin-layer and interface characterization. A powerful method for characterization in the nanometer thickness range is the angle-resolved x-ray photoelectron spectroscopy (ARXPS). This is a nondestructive depth-profiling method, which can provide elemental content as well as chemical information. Two of the drawbacks of ARXPS are, that it requires dedicated mathematical modeling and that, at least up until now, its use has been restricted away from near-surface angles. In this paper we present a method for the mathematical description of a few, hitherto unaccounted, measurement effects in order to improve the simulations of ARXPS data for complex surface structures. As an immediate application, we propose a simple algorithm to consider the effects of elastic scattering in the standard ARXPS data interpretation, which in principle would allow the use of the whole angular range for the analysis; thus leading to a significant increase in the usable information content from the measurements. The potential of this approach is demonstrated with model calculations for a few thin film examples.

  9. Fluctuation X-Ray Scattering

    SciTech Connect (OSTI)

    Saldin, PI: D. K.; Co-I's: J. C. H. Spence and P. Fromme

    2013-01-25T23:59:59.000Z

    The work supported by the grant was aimed at developing novel methods of finding the structures of biomolecules using x-rays from novel sources such as the x-ray free electron laser and modern synchrotrons

  10. Evolution of crystalline structures of poly([epsilon]-caprolactone)/polycarbonate blends; 1: Isothermal crystallization kinetics as probed by synchrotron small-angle x-ray scattering

    SciTech Connect (OSTI)

    Cheung, Y.W.; Stein, R.S. (Univ. of Massachusetts, Amherst, MA (United States). Dept. of Polymer Science and Engineering); Chu, B.; Wu, G. (State Univ. of New York at Stony Brook, Long Island, NY (United States))

    1994-06-20T23:59:59.000Z

    Evolution of the poly([epsilon]-caprolactone) (PCL) lamellae in blends of PCL/PC (polycarbonate) was monitored by synchrotron small-angle X-ray scattering (SAXS). The effects of crystallization temperature, PC concentration, and PC crystallinity on the PCL lamellar growth in the PCL-rich blends were investigated. The half-crystallization time derived from the temporal change of the peak intensity increased with crystallization temperature and generally increased with the addition of PC. For a given blend composition, the lamellar growth rate increased with increasing PC crystallinity. The interlamellar spacing initially varied with time and then approached a plateau value at the later stage of crystallization. An insertion mechanism is proposed in which the PCL is crystallized in the amorphous intralamellar phase. This model is also consistent with the quantitative SAXS results, which suggested that random mixing of PCL and PC lamellae occurred in the semicrystalline (PCL)/semicrystalline (PC) state.

  11. Study of the Crystalline Morphology Evolution of PET and PET/PC Blends by Time-resolved Synchrotron Small Angle X-ray Scattering (SAXS) and DSC

    SciTech Connect (OSTI)

    Barbosa, Irineu; Larocca, Nelson M.; Hage, Elias [Dep. de Engenharia de Materiais, Universidade Federal de Sao Carlos, Sao Carlos, SP (Brazil); Plivelic, Tomas S.; Torriani, Iris L. [Laboratorio Nacional de Luz Sincrotron, Campinas, SP (Brazil); Mantovani, Gerson L. [Centro de Engenharia, Modelagem e Ciencias Sociais Aplicadas, Universidade Federal do ABC, 09090-400 Santo Andre, SP (Brazil)

    2009-01-29T23:59:59.000Z

    Isothermal melt crystallization of poly(ethylene terephthalate)(PET) and PET/PC (polycarbonate) blend, with and without a transesterification catalyst, was studied by time-resolved small-angle X-ray scattering (SAXS) and differential scanning calorimetry (DSC) in order to achieve the variation of the morphological parameters throughout the whole crystallization time. For neat PET, the catalyst promotes a decrease of the crystal lamellar thickness but for the blend no variations were observed. The effect of incorporation of catalyst in crystallization kinetics was very distinct in PET pure and the blend: in the former the catalyst leads to an increase of this kinetics while for the latter it was observed a decreasing.

  12. Ray tracing flux calculation for the small and wide angle x-ray scattering diffraction station at the SESAME synchrotron radiation facility

    SciTech Connect (OSTI)

    Salah, Wa'el [Synchrotron-light for Experimental Science and Application in the Middle East (SESAME), P.O. Box 7, Allan 19252 (Jordan); Department of Physics, The Hashemite University, Zarqa 13115 (Jordan); Sanchez del Rio, M. [European Synchrotron Radiation Facility, Bp 220, 38043 Grenoble Cedex (France); Hoorani, H. [Synchrotron-light for Experimental Science and Application in the Middle East (SESAME), P.O. Box 7, Allan 19252 (Jordan)

    2009-09-15T23:59:59.000Z

    The calculation for the optics of the synchrotron radiation small and wide angle x-ray scattering beamline, currently under construction at SESAME is described. This beamline is based on a cylindrically bent germanium (111) single crystal with an asymmetric cut of 10.5 deg., followed by a 1.2 m long rhodium coated plane mirror bent into a cylindrical form. The focusing properties of bent asymmetrically cut crystals have not yet been studied in depth. The present paper is devoted to study of a particular application of a bent asymmetrically cut crystal using ray tracing simulations with the SHADOW code. These simulations show that photon fluxes of order of 1.09x10{sup 11} photons/s will be available at the experimental focus at 8.79 keV. The focused beam dimensions will be 2.2 mm horizontal full width at half maximum (FWHM) by 0.12 mm vertical (FWHM).

  13. Crystal Structures and Small-angle X-ray Scattering Analysis of UDP-galactopyranose Mutase from the Pathogenic Fungus Aspergillus fumigatus

    SciTech Connect (OSTI)

    Dhatwalia, Richa; Singh, Harkewal; Oppenheimer, Michelle; Karr, Dale B.; Nix, Jay C.; Sobrado, Pablo; Tanner, John J. (Missouri); (LBNL); (VPI-SU)

    2012-05-14T23:59:59.000Z

    UDP-galactopyranose mutase (UGM) is a flavoenzyme that catalyzes the conversion of UDP-galactopyranose to UDP-galactofuranose, which is a central reaction in galactofuranose biosynthesis. Galactofuranose has never been found in humans but is an essential building block of the cell wall and extracellular matrix of many bacteria, fungi, and protozoa. The importance of UGM for the viability of many pathogens and its absence in humans make UGM a potential drug target. Here we report the first crystal structures and small-angle x-ray scattering data for UGM from the fungus Aspergillus fumigatus, the causative agent of aspergillosis. The structures reveal that Aspergillus UGM has several extra secondary and tertiary structural elements that are not found in bacterial UGMs yet are important for substrate recognition and oligomerization. Small-angle x-ray scattering data show that Aspergillus UGM forms a tetramer in solution, which is unprecedented for UGMs. The binding of UDP or the substrate induces profound conformational changes in the enzyme. Two loops on opposite sides of the active site move toward each other by over 10 {angstrom} to cover the substrate and create a closed active site. The degree of substrate-induced conformational change exceeds that of bacterial UGMs and is a direct consequence of the unique quaternary structure of Aspergillus UGM. Galactopyranose binds at the re face of the FAD isoalloxazine with the anomeric carbon atom poised for nucleophilic attack by the FAD N5 atom. The structural data provide new insight into substrate recognition and the catalytic mechanism and thus will aid inhibitor design.

  14. Nonlinear X-ray Compton Scattering

    E-Print Network [OSTI]

    Fuchs, Matthias; Chen, Jian; Ghimire, Shambhu; Shwartz, Sharon; Kozina, Michael; Jiang, Mason; Henighan, Thomas; Bray, Crystal; Ndabashimiye, Georges; Bucksbaum, P H; Feng, Yiping; Herrmann, Sven; Carini, Gabriella; Pines, Jack; Hart, Philip; Kenney, Christopher; Guillet, Serge; Boutet, Sebastien; Williams, Garth; Messerschmidt, Marc; Seibert, Marvin; Moeller, Stefan; Hastings, Jerome B; Reis, David A

    2015-01-01T23:59:59.000Z

    X-ray scattering is a weak linear probe of matter. It is primarily sensitive to the position of electrons and their momentum distribution. Elastic X-ray scattering forms the basis of atomic structural determination while inelastic Compton scattering is often used as a spectroscopic probe of both single-particle excitations and collective modes. X-ray free-electron lasers (XFELs) are unique tools for studying matter on its natural time and length scales due to their bright and coherent ultrashort pulses. However, in the focus of an XFEL the assumption of a weak linear probe breaks down, and nonlinear light-matter interactions can become ubiquitous. The field can be sufficiently high that even non-resonant multiphoton interactions at hard X-rays wavelengths become relevant. Here we report the observation of one of the most fundamental nonlinear X-ray-matter interactions, the simultaneous Compton scattering of two identical photons producing a single photon at nearly twice the photon energy. We measure scattered...

  15. Small-angle scattering investigations of poly([epsilon]-caprolactone)/polycarbonate blends -- 2: Small-angle X-ray and light scattering study of semicrystalline/semicrystalline and semicrystalline/amorphous blend morphologies

    SciTech Connect (OSTI)

    Cheung, Y.W.; Stein, R.S. (Univ. of Massachusetts, Amherst, MA (United States). Dept. of Polymer Science and Engineering); Lin, J.S.; Wignall, G.D. (Oak Ridge National Lab., Oak Ridge, TN (United States))

    1994-04-25T23:59:59.000Z

    Crystalline morphologies of poly([epsilon]-caprolactone) (PCL) and polycarbonate (PC) blends were probed with small-angle X-ray scattering (SAXS) and small-angle light scattering (SALS). Quantitative SAXS analysis suggested that random mixing of PCL and PC lamellae occurred in the semicrystalline/semicrystalline state. Two distinct regions of incorporation were identified in the semicrystalline/amorphous state. It was found that PCL was rejected from the PC interlamellar region in the PCL-rich blends. In contrast, PCL was incorporated into the amorphous phase between the crystalline lamellae in the PC-rich blends. This transition from interlamellar exclusion to interlamellar inclusion may be related to the glass transition temperatures or the mobility of the blends. It is proposed that the mode of incorporation or exclusion is governed by the competition between entropy and diffusion. Additionally, SALS coupled with optical microscopy indicated that PC is an effective nucleating agent for PCL crystallization as manifested by the reduction of PCL spherulitic size with the addition of PC.

  16. J. Mol. Biol. (1975) 99, 15-25 On the Interpretation of Small-angle X-ray Solution Scattering

    E-Print Network [OSTI]

    Harrison, Stephen C.

    1975-01-01T23:59:59.000Z

    scattering points of unit weight with angular co-ordinates 8t, ~b~,we have g, = Y..:,* (el,i,,) (2) t=1 since

  17. Probing the MgATP-Bound Conformation of the Nitrogenase Fe Protein By Solution Small-Angle X-Ray Scattering

    SciTech Connect (OSTI)

    Sarma, R.; Mulder, D.W.; Brecht, E.; Szilagyi, R.K.; Seefeldt, L.C.; Tsuruta, H.; Peters, J.W.; /Montana State U. /SLAC, SSRL /Utah State U.

    2009-04-30T23:59:59.000Z

    The MgATP-bound conformation of the Fe protein of nitrogenase from Azotobacter vinelandii has been examined in solution by small-angle X-ray scattering (SAXS) and compared to existing crystallographically characterized Fe protein conformations. The results of the analysis of the crystal structure of an Fe protein variant with a Switch II single-amino acid deletion recently suggested that the MgATP-bound state of the Fe protein may exist in a conformation that involves a large-scale reorientation of the dimer subunits, resulting in an overall elongated structure relative to the more compact structure of the MgADP-bound state. It was hypothesized that the Fe protein variant may be a conformational mimic of the MgATP-bound state of the native Fe protein largely on the basis of the observation that the spectroscopic properties of the [4Fe-4S] cluster of the variant mimicked in part the spectroscopic signatures of the native nitrogenase Fe protein in the MgATP-bound state. In this work, SAXS studies reveal that the large-scale conformational differences between the native Fe protein and the variant observed by X-ray crystallography are also observed in solution. In addition, comparison of the SAXS curves of the Fe protein nucleotide-bound states to the nucleotide-free states indicates that the conformation of the MgATP-bound state in solution does not resemble the structure of the variant as initially proposed, but rather, at the resolution of this experiment, it resembles the structure of the nucleotide-free state. These results provide insights into the Fe protein conformations that define the role of MgATP in nitrogenase catalysis.

  18. Surface Area and Microporosity of Carbon Aerogels from Gas Adsorption and Small- and Wide-Angle X-ray Scattering Measurements

    E-Print Network [OSTI]

    David Fairén-jiménez; Francisco Carrasco-marín; David Djurado; Françoise Bley; Françoise Ehrburger-dolle; Carlos Moreno-castilla

    2005-01-01T23:59:59.000Z

    A carbon aerogel was obtained by carbonization of an organic aerogel prepared by sol-gel polymerization of resorcinol and formaldehyde in water. The carbon aerogel was then CO2 activated at 800 °C to increase its surface area and widen its microporosity. Evolution of these parameters was followed by gas adsorption and small- and wide-angle X-ray scattering (SAXS and WAXS, respectively) with contrast variation by using dry and wet (immersion in benzene and m-xylene) samples. For the original carbon aerogel, the surface area, SSAXS, obtained by SAXS, is larger than that obtained by gas adsorption (Sads). The values become nearly the same as the degree of activation of the carbon aerogel increases. This feature is due to the widening of the narrow microporosity in the carbon aerogel as the degree of activation is increased. In addition, WAXS results show that the short-range spatial correlations into the assemblies of hydrocarbon molecules confined inside the micropores are different from those existing in the liquid phase. 1.

  19. Neutron and X-ray Scattering Study of Magnetic Manganites

    E-Print Network [OSTI]

    Boothroyd, Andrew

    Neutron and X-ray Scattering Study of Magnetic Manganites Graeme Eoin Johnstone A Thesis submitted are performed using a variety of neutron scattering and x-ray scattering techniques. The electronic ground for analysing the results of the polarised neutron scattering experiment. There are a large number of people who

  20. Fourteenth National School on Neutron and X-ray Scattering

    E-Print Network [OSTI]

    Pennycook, Steve

    Fourteenth National School on Neutron and X-ray Scattering August 12 - 25, 2012 at Argonne National of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major Ridge National Laboratory's Neutron Scattering Science Division. Scientific Directors: Jonathan C. Lang

  1. Tenth National School on Neutron and X-ray Scattering

    E-Print Network [OSTI]

    Pennycook, Steve

    Tenth National School on Neutron and X-ray Scattering September 24 - October 11, 2008 at Argonne of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major National Laboratory's Neutron Scattering Science Division. Scientific Directors: Jonathan C. Lang, Suzanne

  2. National School on Neutron and X-ray Scattering

    E-Print Network [OSTI]

    15th National School on Neutron and X-ray Scattering August 10 - 24, 2013 at Argonne National of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major Ridge National Laboratory's Neutron Scattering Science Division. Scientific Directors: Jonathan C. Lang

  3. Thirteenth National School on Neutron and X-ray Scattering

    E-Print Network [OSTI]

    Thirteenth National School on Neutron and X-ray Scattering June 11 ­ June 25, 2011 at Argonne of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major National Laboratory's Neutron Scattering Science Division. Scientific Directors: Jonathan C. Lang, Suzanne

  4. Sixteenth National School on Neutron and X-ray Scattering

    E-Print Network [OSTI]

    Pennycook, Steve

    Sixteenth National School on Neutron and X-ray Scattering June 14-28, 2014 at Argonne National of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major's Neutron Scattering Science Division. Scientific Directors: Suzanne G.E. te Velthuis, Esen Ercan Alp

  5. Twelfth National School on Neutron and X-ray Scattering

    E-Print Network [OSTI]

    Pennycook, Steve

    Twelfth National School on Neutron and X-ray Scattering June 12 ­ June 26, 2010 at Argonne National of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major National Laboratory's Neutron Scattering Science Division. Scientific Directors: Jonathan C. Lang, Suzanne

  6. National School on Neutron and X-ray Scattering

    E-Print Network [OSTI]

    Pennycook, Steve

    National School on Neutron and X-ray Scattering May 30 ­ June 13, 2009 at Argonne National of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major National Laboratory's Neutron Scattering Science Division. Scientific Directors: Jonathan C. Lang, Suzanne

  7. A sample cell to study hydrate formation with x-ray scattering

    SciTech Connect (OSTI)

    Conrad, Heiko; Lehmkuehler, Felix; Sternemann, Christian; Feroughi, Omid; Tolan, Metin [Fakultaet Physik/DELTA, Technische Universitaet Dortmund, Maria-Goeppert-Mayer-Str. 2, Dortmund D-44221 (Germany); Simonelli, Laura; Huotari, Simo [European Synchrotron Radiation Facility, Boite Postale 220, Grenoble Cedex 9 F-38043 (France)

    2009-02-15T23:59:59.000Z

    We present a new sample cell for measuring nonresonant inelastic x-ray scattering spectra of a tetrahydrofuran (THF)-water liquid mixture and THF hydrate. The hydrate is formed inside the cell after nucleation seeds have been offered by a special magnetic stirring mechanism. Hydrate formation was verified by wide angle x-ray scattering and nonresonant x-ray Raman scattering spectra at the oxygen K-edge. A broad range of scattering angles can be studied with this cell which is necessary for momentum transfer dependent inelastic x-ray scattering. This cell is ideal to examine other liquid hydrate formers or other liquid samples, which have to be mixed in situ during the measurements.

  8. Structure of low-density nanoporous dielectrics revealed by low-vacuum electron microscopy and small-angle x-ray scattering

    SciTech Connect (OSTI)

    Kucheyev, S O; Toth, M; Baumann, T F; Hamza, A V; Ilavsky, J; Knowles, W R; Thiel, B L; Tileli, V; van Buuren, T; Wang, Y M; Willey, T M

    2006-06-05T23:59:59.000Z

    We use low-vacuum scanning electron microscopy to image directly the ligament and pore size and shape distributions of representative aerogels over a wide range of length scales ({approx} 10{sup 0}-10{sup 5} nm). The images are used for unambiguous, real-space interpretation of small-angle scattering data for these complex nanoporous systems.

  9. The Dust Scattering Model Can Not Explain The Shallow X-ray Decay in GRB Afterglows

    E-Print Network [OSTI]

    Rong-Feng Shen; Richard Willingale; Pawan Kumar; Paul T. O'Brien; Phil A. Evans

    2009-03-02T23:59:59.000Z

    A dust scattering model was recently proposed to explain the shallow X-ray decay (plateau) observed prevalently in Gamma-Ray Burst (GRB) early afterglows. In this model the plateau is the scattered prompt X-ray emission by the dust located close (about 10 to a few hundred pc) to the GRB site. In this paper we carefully investigate the model and find that the scattered emission undergoes strong spectral softening with time, due to the model's essential ingredient that harder X-ray photons have smaller scattering angle thus arrive earlier, while softer photons suffer larger angle scattering and arrive later. The model predicts a significant change, i.e., $\\Delta \\b \\sim 2 - 3$, in the X-ray spectral index from the beginning of the plateau toward the end of the plateau, while the observed data shows close to zero softening during the plateau and the plateau-to-normal transition phase. The scattering model predicts a big difference between the harder X-ray light curve and the softer X-ray light curve, i.e., the plateau in harder X-rays ends much earlier than in softer X-rays. This feature is not seen in the data. The large scattering optical depths of the dust required by the model imply strong extinction in optical, $A_V \\gtrsim $ 10, which contradicts current findings of $A_V= 0.1 - 0.7$ from optical and X-ray afterglow observations. We conclude that the dust scattering model can not explain the X-ray plateaus.

  10. HIV-1 Tat membrane interactions probed using X-ray and neutron scattering, CD spectroscopy and MD simulations

    E-Print Network [OSTI]

    Nagle, John F.

    HIV-1 Tat membrane interactions probed using X-ray and neutron scattering, CD spectroscopy and MD translocation, were provided by wide-angle X-ray scattering (WAXS) and neutron scattering. CD spectroscopy for Neutron Research, 100 Bureau Drive, Stop 6102, Gaithersburg, MD 20899, United States d CHESS, Cornell

  11. Scattering of x rays from low-Z materials

    SciTech Connect (OSTI)

    Gaines, J.L.; Kissel, L.D.; Catron, H.C.; Hansen, R.A.

    1980-08-01T23:59:59.000Z

    X rays incident on thin beryllium, boron, carbon, and other low-Z materials undergo both elastic and inelastic scattering as well as diffraction from the crystalline or crystalline-like structure of the material. Unpolarized monoenergetic x rays in the 1.5 to 8.0-keV energy range were used to determine the absolute scattering efficiency of thin beryllium, carbon, and boron foils. These measurements are compared to calculated scattering efficiencies predicted by single-atom theories. In addition, the relative scattering efficiency versus x-ray energy was measured for other low-Z foils using unpolarized bremsstrahlung x rays. In all the low-Z foils examined, we observed Bragg-like x-ray diffraction due to the ordered structure of the materials.

  12. Imaging Quantum States with X-ray Compton Scattering | Stanford...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Imaging Quantum States with X-ray Compton Scattering Wednesday, April 8, 2015 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Speaker: Yoshiharu Sakurai (Japan Synchrotron...

  13. Magnetism studies using resonant, coherent, x-ray scattering...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Magnetism studies using resonant, coherent, x-ray scattering Monday, September 10, 2012 - 10:00am SLAC, Bldg. 137, Room 226 Keoki Seu Seminar: With the advent of free electron...

  14. X-ray server : an outline resource for simulations of x-ray diffraction and scattering.

    SciTech Connect (OSTI)

    Stepanov, S.; Biosciences Division

    2004-01-01T23:59:59.000Z

    X-ray Server is a public project operational at the APS since 1997 with the goals to explore novel network technologies for providing wide scientific community with access to personal research results, establishing scientific collaborations, and refining scientific software. The Server provides Web-based access to a number of programs developed by the author in the field of X-ray diffraction and scattering. The software code operates directly on the Server available for use without downloading. Currently seven programs are accessible that have been used more than 85,000 times. This report discusses the Server philosophy, provides an overview of the physical models and algorithms beneath the codes and demonstrates some applications of the programs. It is shown with examples and statistics how the Server goals are achieved. The plans for further X-ray Server development are outlined.

  15. High performance x-ray anti-scatter grid

    DOE Patents [OSTI]

    Logan, C.M.

    1995-05-23T23:59:59.000Z

    Disclosed are an x-ray anti-scatter grid for x-ray imaging, particularly for screening mammography, and method for fabricating same, x-rays incident along a direct path pass through a grid composed of a plurality of parallel or crossed openings, microchannels, grooves, or slots etched in a substrate, such as silicon, having the walls of the microchannels or slots coated with a high opacity material, such as gold, while x-rays incident at angels with respect to the slots of the grid, arising from scatter, are blocked. The thickness of the substrate is dependent on the specific application of the grid, whereby a substrate of the grid for mammography would be thinner than one for chest radiology. Instead of coating the walls of the slots, such could be filed with an appropriate liquid, such as mercury. 4 Figs.

  16. High performance x-ray anti-scatter grid

    DOE Patents [OSTI]

    Logan, Clinton M. (Pleasanton, CA)

    1995-01-01T23:59:59.000Z

    An x-ray anti-scatter grid for x-ray imaging, particularly for screening mammography, and method for fabricating same, x-rays incident along a direct path pass through a grid composed of a plurality of parallel or crossed openings, microchannels, grooves, or slots etched in a substrate, such as silicon, having the walls of the microchannels or slots coated with a high opacity material, such as gold, while x-rays incident at angels with respect to the slots of the grid, arising from scatter, are blocked. The thickness of the substrate is dependent on the specific application of the grid, whereby a substrate of the grid for mammography would be thinner than one for chest radiology. Instead of coating the walls of the slots, such could be filed with an appropriate liquid, such as mercury.

  17. Accepted Manuscript Using Small Angle Solution Scattering Data in Xplor-NIH Structure Calcula-

    E-Print Network [OSTI]

    Clore, G. Marius

    and wide angle X-ray and small angle neutron scattering for biomolecular structure calculation using and wide angle X-ray scattering (SAXS/WAXS) and small angle neutron scattering (SANS) data, on the otherAccepted Manuscript Using Small Angle Solution Scattering Data in Xplor-NIH Structure Calcula

  18. Structural characterization of Green River oil-shale at high-pressure using pair distribution function analysis and small angle x-ray scattering.

    SciTech Connect (OSTI)

    Locke, D. R.; Chupas, P. J.; Chapman, K. W.; Pugmire, R. J.; Winans, R. E.; Univ. of Utah

    2008-01-01T23:59:59.000Z

    The compression behavior of a silicate-rich oil shale from the Green River formation in the pressure range 0.0-2.4 GPa was studied using in situ high pressure X-ray pair distribution function (PDF) measurements for the sample contained within a Paris-Edinburgh cell. The real-space local structural information in the PDF, G(r), was used to evaluate the compressibility of the oil shale. Specifically, the pressure-induced reduction in the medium- to long-range atom distances (6-20 {angstrom}) yielded an average sample compressibility corresponding to a bulk modulus of ca. 61-67 GPa. A structural model consisting of a three phase mixture of the principal crystalline oil shale components (quartz, albite and Illite) provided a good fit to the ambient pressure PDF data (R 30.7%). Indeed the features in the PDF beyond 6 {angstrom}, were similarly well fit by a single phase model of the highest symmetry, highly crystalline quartz component.

  19. Imaging X-ray Thomson Scattering Spectrometer Design and Demonstration

    SciTech Connect (OSTI)

    Gamboa, E.J. [University of Michigan; Huntington, C.M. [University of Michigan; Trantham, M.R. [University of Michigan; Keiter, P.A [University of Michigan; Drake, R.P. [University of Michigan; Montgomery, David [Los Alamos National Laboratory; Benage, John F. [Los Alamos National Laboratory; Letzring, Samuel A. [Los Alamos National Laboratory

    2012-05-04T23:59:59.000Z

    In many laboratory astrophysics experiments, intense laser irradiation creates novel material conditions with large, one-dimensional gradients in the temperature, density, and ionization state. X-ray Thomson scattering is a powerful technique for measuring these plasma parameters. However, the scattered signal has previously been measured with little or no spatial resolution, which limits the ability to diagnose inhomogeneous plasmas. We report on the development of a new imaging x-ray Thomson spectrometer (IXTS) for the Omega laser facility. The diffraction of x-rays from a toroidally-curved crystal creates high-resolution images that are spatially resolved along a one-dimensional profile while spectrally dispersing the radiation. This focusing geometry allows for high brightness while localizing noise sources and improving the linearity of the dispersion. Preliminary results are presented from a scattering experiment that used the IXTS to measure the temperature profile of a shocked carbon foam.

  20. Ab initio studies of ultrafast x-ray scattering of the photodissociation of iodine

    SciTech Connect (OSTI)

    Debnarova, Andrea; Techert, Simone [Max Planck Institute for Biophysical Chemistry, 37077 Goettingen, Am Fassberg 11 (Germany); Schmatz, Stefan [Institut fuer Physikalische Chemie, Universitaet Goettingen, 37077 Goettingen, Tammannstr. 6 (Germany)

    2010-09-28T23:59:59.000Z

    We computationally examine various aspects of the reaction dynamics of the photodissociation and recombination of molecular iodine. We use our recently proposed formalism to calculate time-dependent x-ray scattering signal changes from first principles. Different aspects of the dynamics of this prototypical reaction are studied, such as coherent and noncoherent processes, features of structural relaxation that are periodic in time versus nonperiodic dissociative processes, as well as small electron density changes caused by electronic excitation, all with respect to x-ray scattering. We can demonstrate that wide-angle x-ray scattering offers a possibility to study the changes in electron densities in nonperiodic systems, which render it a suitable technique for the investigation of chemical reactions from a structural dynamics point of view.

  1. Structural dynamics and ssDNA binding activity of the three N-terminal domains of the large subunit of Replication Protein A from small angle X-ray scattering

    SciTech Connect (OSTI)

    Pretto, Dalyir I.; Tsutakawa, Susan; Brosey, Chris A.; Castillo, Amalchi; Chagot, Marie-Eve; Smith, Jarrod A.; Tainer, John A.; Chazin, Walter J.

    2010-03-11T23:59:59.000Z

    Replication Protein A (RPA) is the primary eukaryotic ssDNA binding protein utilized in diverse DNA transactions in the cell. RPA is a heterotrimeric protein with seven globular domains connected by flexible linkers, which enable substantial inter-domain motion that is essential to its function. Small angle X-ray scattering (SAXS) experiments on two multi-domain constructs from the N-terminus of the large subunit (RPA70) were used to examine the structural dynamics of these domains and their response to the binding of ssDNA. The SAXS data combined with molecular dynamics simulations reveal substantial interdomain flexibility for both RPA70AB (the tandem high affinity ssDNA binding domains A and B connected by a 10-residue linker) and RPA70NAB (RPA70AB extended by a 70-residue linker to the RPA70N protein interaction domain). Binding of ssDNA to RPA70NAB reduces the interdomain flexibility between the A and B domains, but has no effect on RPA70N. These studies provide the first direct measurements of changes in orientation of these three RPA domains upon binding ssDNA. The results support a model in which RPA70N remains structurally independent of RPA70AB in the DNA bound state and therefore freely available to serve as a protein recruitment module.

  2. Crystal defect studies using x-ray diffuse scattering

    SciTech Connect (OSTI)

    Larson, B.C.

    1980-01-01T23:59:59.000Z

    Microscopic lattice defects such as point (single atom) defects, dislocation loops, and solute precipitates are characterized by local electronic density changes at the defect sites and by distortions of the lattice structure surrounding the defects. The effect of these interruptions of the crystal lattice on the scattering of x-rays is considered in this paper, and examples are presented of the use of the diffuse scattering to study the defects. X-ray studies of self-interstitials in electron irradiated aluminum and copper are discussed in terms of the identification of the interstitial configuration. Methods for detecting the onset of point defect aggregation into dislocation loops are considered and new techniques for the determination of separate size distributions for vacancy loops and interstitial loops are presented. Direct comparisons of dislocation loop measurements by x-rays with existing electron microscopy studies of dislocation loops indicate agreement for larger size loops, but x-ray measurements report higher concentrations in the smaller loop range. Methods for distinguishing between loops and three-dimensional precipitates are discussed and possibilities for detailed studies considered. A comparison of dislocation loop size distributions obtained from integral diffuse scattering measurements with those from TEM show a discrepancy in the smaller sizes similar to that described above.

  3. In Situ X-Ray Scattering Helps Optimize Printed Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    In Situ X-Ray Scattering Helps Optimize Printed Solar Cells In Situ X-Ray Scattering Helps Optimize Printed Solar Cells Print Wednesday, 25 February 2015 00:00 Plastic solar cells...

  4. SMB, Small Angle X-Ray Scattering

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiation Protection245C Unlimited ReleaseWelcome to the

  5. National School on Neutron and X-ray Scattering August 10-24, 2013

    E-Print Network [OSTI]

    Kemner, Ken

    National School on Neutron and X-ray Scattering August 10-24, 2013 Argonne National Laboratory National Laboratory 3:15 ­ 3:30 Break #12;National School on Neutron and X-ray Scattering August 10 Dinner Week 1 wrap-up Picnic #12;National School on Neutron and X-ray Scattering August 10-24, 2012 Oak

  6. In situ small angle x-ray studies of coal gasification

    SciTech Connect (OSTI)

    Jensen, K F

    1983-01-01T23:59:59.000Z

    This report summarizes the progress made the first 12 months of a planned 36 month project on small angle x-ray studies of coal and char pore structure. Model carbon studies have been employed to demonstrate the usefulness of small angle x-ray scattering (SAXS) in monitoring the structural changes in porous carbonaceous materials during gasification. Scattering data from particles gasified to varying levels of conversion show increases in the micropore sizes with conversion. This is also supported by surface area measurements by SAXS showing a maximum at intermediate conversion in agreements with previous studies by conventional means. The application of SAXS to PSOC coal samples is also demonstrated. Existing models for the porous structure have been reviewed and percolation theory has been selected as a consistent framework for both the modelling and the data analysis. This theory will make it possible to describe the porous structure in terms of its geometry and connectivity, rather than being limited to a fixed geometry as in conventional approaches. Two graduate students and the PI have been trained in SAXS and the associated theory. Results from the model carbon studies have been published. 18 references, 9 figures, 2 tables.

  7. 2011 U.S. National School on Neutron and X-ray Scattering

    SciTech Connect (OSTI)

    Lang, Jonathan [Argonne National Laboratory (ANL); te Vethuis, Suzanne [Argonne National Laboratory (ANL); Ekkebus, Allen E [ORNL; Chakoumakos, Bryan C [ORNL; Budai, John D [ORNL

    2012-01-01T23:59:59.000Z

    The 13th annual U.S. National School on Neutron and X-ray Scattering was held June 11 to 25, 2011, at both Oak Ridge and Argonne National Laboratories. This school brought together 65 early career graduate students from 56 different universities in the US and provided them with a broad introduction to the techniques available at the major large-scale neutron and synchrotron x-ray facilities. This school is focused primarily on techniques relevant to the physical sciences, but also touches on cross-disciplinary bio-related scattering measurements. During the school, students received lectures by over 30 researchers from academia, industry, and national laboratories and participated in a number of short demonstration experiments at Argonne's Advanced Photon Source (APS) and Oak Ridge's Spallation neutron Source (SNS) and High Flux Isotope Reactor (HFIR) facilities to get hands-on experience in using neutron and synchrotron sources. The first week of this year's school was held at Oak Ridge National Lab, where Lab director Thom Mason welcomed the students and provided a shitorical perspective of the neutron and x-ray facilities both at Oak Ridge and Argonne. The first few days of the school were dedicated to lectures laying out the basics of scattering theory and the differences and complementarity between the neutron and x-ray probes given by Sunil Sinha. Jack Carpenter provided an introduction into how neutrons are generated and detected. After this basic introduction, the students received lectures each morning on specific techniques and conducted demonstration experiments each afternoon on one of 15 different instruments at either the SNS or HFIR. Some of the topics covered during this week of the school included inelastic neutron scattering by Bruce Gaulin, x-ray and neutron reflectivity by Chuck Majkrazak, small-angle scattering by Volker Urban, powder diffraction by Ashfia Huq and diffuse scattering by Gene Ice.

  8. angle x-ray absorption: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    angle x-ray absorption First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Time Resolved X-Ray Absorption...

  9. National School on Neutron and X-ray Scattering June 14-28, 2014

    E-Print Network [OSTI]

    Kemner, Ken

    National School on Neutron and X-ray Scattering June 14-28, 2014 Argonne National Laboratory:00 Dinner Dinner Dinner Dinner Week 1 wrap-up Picnic #12;National School on Neutron and X-ray Scattering Restaurant 9:45 - 10:45 Lecture Interaction of X-rays and Neutrons with Matter Roger Pynn University

  10. IN SITU SURFACE X-RAY SCATTERING STUDIES OF ELECTROSORPTION

    SciTech Connect (OSTI)

    WANG,J.X.; ADZIC,R.R.; OCKO,B.M.

    1998-07-01T23:59:59.000Z

    A short review of the application of surface x-ray scattering techniques to the electrode/electrolyte interfaces is presented. Recent results on metal, halide, and metal-halide adlayers with three specific systems: Bi on Au(100) and Au(110); Br on Au(100) and Ag(100); and the coadsorption of Tl with Br or I on Au(111), are given as an illustration. Factors affecting ordering of pure metal and halide adlayers and the metal-halide surface compounds are discussed in some detail.

  11. SU-E-I-01: A Fast, Analytical Pencil Beam Based Method for First Order X-Ray Scatter Estimation of Kilovoltage Cone Beam X-Rays

    SciTech Connect (OSTI)

    Liu, J; Bourland, J [Wake Forest University, Winston-salem, NC (United States)

    2014-06-01T23:59:59.000Z

    Purpose: To analytically estimate first-order x-ray scatter for kV cone beam x-ray imaging with high computational efficiency. Methods: In calculating first-order scatter using the Klein-Nishina formula, we found that by integrating the point-to-point scatter along an interaction line, a “pencil-beam” scatter kernel (BSK) can be approximated to a quartic expression when the imaging field is small. This BSK model for monoenergetic, 100keV x-rays has been verified on homogeneous cube and cylinder water phantoms by comparing with the exact implementation of KN formula. For heterogeneous medium, the water-equivalent length of a BSK was acquired with an improved Siddon's ray-tracing algorithm, which was also used in calculating pre- and post- scattering attenuation. To include the electron binding effect for scattering of low-kV photons, the mean corresponding scattering angle is determined from the effective point of scattered photons of a BSK. The behavior of polyenergetic x-rays was also investigated for 120kV x-rays incident to a sandwiched infinite heterogeneous slab phantom, with the electron binding effect incorporated. Exact computation and Monte Carlo simulations were performed for comparisons, using the EGSnrc code package. Results: By reducing the 3D volumetric target (o(n{sup 3})) to 2D pencil-beams (o(n{sup 2})), the computation expense can be generally lowered by n times, which our experience verifies. The scatter distribution on a flat detector shows high agreement between the analytic BSK model and exact calculations. The pixel-to-pixel differences are within (-2%, 2%) for the homogeneous cube and cylinder phantoms and within (0, 6%) for the heterogeneous slab phantom. However, the Monte Carlo simulation shows increased deviation of the BSK model toward detector periphery. Conclusion: The proposed BSK model, accommodating polyenergetic x-rays and electron binding effect at low kV, shows great potential in efficiently estimating the first-order scatter from small imaging fields. We are investigating more thoroughly to improve performance and explore applications.

  12. Reflectivity and scattering measurements of an Advanced X-ray Astrophysics Facility test coating sample

    SciTech Connect (OSTI)

    Bixler, J.V.; Mauche, C.W.; Hailey, C.J.; Madison, L. [Laboratory for Experimental Astrophysics, Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    1995-10-01T23:59:59.000Z

    Reflectivity and scattering profile measurements were made on a gold-coated witness sample produced to evaluate mirror coatings for the Advanced X-ray Astrophysics Facility program. Reflectivity measurements were made at Al K, Ti K, and Cu K energies as a function of incident graze angle. The results are fit to a model that includes the effects of roughness, particulate and organic contamination layers, and gold-coating density. Reflectivities are close to theoretical, with the difference being well accounted for by 4.1 A of roughness at spatial frequencies above 4 {mu}m{sup {minus}1}, a gold-coating density equal to 0.98 bulk, and a surface contaminant layer 27 A thick. Scattering measurements extending to {plus_minus}35 arcmin of the line center were obtained by the use of Al K x rays and incidence angles from 0.75{degree} to 3{degree}. The scattering profiles imply a power spectral density of surface-scattering frequencies that follows a power law with an index of {minus}1.0 and a total surface roughness for the spatial frequency band between 0.05 {mu}m{sup {minus}1} and 4 {mu}m{sup {minus}1} of 3.3 A. Combining the roughnesses derived from both the reflectivity and scattering measurements yields a total roughness of 5.3 A for scattering frequencies between 0.05 {mu}m{sup {minus}1} and 15,000 {mu}m{sup {minus}1}.

  13. Neutron and X-ray Scattering Studies of Strongly Correlated Electron Systems

    E-Print Network [OSTI]

    Boothroyd, Andrew

    Neutron and X-ray Scattering Studies of Strongly Correlated Electron Systems Russell A. Ewings 2008 #12;Abstract Neutron and X-ray Scattering Studies of Strongly Correlated Electron Systems Russell-ray scattering and neutron scattering experiments on several strongly correlated transition metal oxides

  14. Imaging Nonequilibrium Atomic Vibrations with X-ray Diffuse Scattering

    SciTech Connect (OSTI)

    Trigo, M.; Chen, J.; Vishwanath, V.H.; /SLAC; Sheu, Y.M.; /Michigan U.; Graber, T.; Henning, R.; /U. Chicago; Reis, D; /SLAC /Stanford U., Appl. Phys. Dept.; ,

    2011-03-03T23:59:59.000Z

    We use picosecond x-ray diffuse scattering to image the nonequilibrium vibrations of the lattice following ultrafast laser excitation. We present images of nonequilibrium phonons in InP and InSb throughout the Brillouin-zone which remain out of equilibrium up to nanoseconds. The results are analyzed using a Born model that helps identify the phonon branches contributing to the observed features in the time-resolved diffuse scattering. In InP this analysis shows a delayed increase in the transverse acoustic (TA) phonon population along high-symmetry directions accompanied by a decrease in the longitudinal acoustic (LA) phonons. In InSb the increase in TA phonon population is less directional.

  15. Air-core grid for scattered x-ray rejection

    DOE Patents [OSTI]

    Logan, Clinton M. (Pleasanton, CA); Lane, Stephen M. (Oakland, CA)

    1995-01-01T23:59:59.000Z

    The invention is directed to a grid used in x-ray imaging applications to block scattered radiation while allowing the desired imaging radiation to pass through, and to process for making the grid. The grid is composed of glass containing lead oxide, and eliminates the spacer material used in prior known grids, and is therefore, an air-core grid. The glass is arranged in a pattern so that a large fraction of the area is open allowing the imaging radiation to pass through. A small pore size is used and the grid has a thickness chosen to provide high scatter rejection. For example, the grid may be produced with a 200 .mu.m pore size, 80% open area, and 4 mm thickness.

  16. Air-core grid for scattered x-ray rejection

    DOE Patents [OSTI]

    Logan, C.M.; Lane, S.M.

    1995-10-03T23:59:59.000Z

    The invention is directed to a grid used in x-ray imaging applications to block scattered radiation while allowing the desired imaging radiation to pass through, and to process for making the grid. The grid is composed of glass containing lead oxide, and eliminates the spacer material used in prior known grids, and is therefore, an air-core grid. The glass is arranged in a pattern so that a large fraction of the area is open allowing the imaging radiation to pass through. A small pore size is used and the grid has a thickness chosen to provide high scatter rejection. For example, the grid may be produced with a 200 {micro}m pore size, 80% open area, and 4 mm thickness. 2 figs.

  17. Spectral softening in the X-RAY afterglow of GRB 130925A as predicted by the dust scattering model

    SciTech Connect (OSTI)

    Zhao, Yi-Nan; Shao, Lang, E-mail: lshao@hebtu.edu.cn [Department of Space Science and Astronomy, Hebei Normal University, Shijiazhuang 050024 (China)

    2014-07-01T23:59:59.000Z

    Gamma-ray bursts (GRBs) usually occur in a dense star-forming region with a massive circumburst medium. The small-angle scattering of intense prompt X-ray emission off the surrounding dust grains will have observable consequences and sometimes can dominate the X-ray afterglow. In most of the previous studies, only the Rayleigh-Gans (RG) approximation is employed for describing the scattering process, which works accurately for the typical size of grains (with radius of a ? 0.1 ?m) in the diffuse interstellar medium. When the size of the grains may significantly increase, as in a more dense region where GRBs would occur, the RG approximation may not be valid enough for modeling detailed observational data. In order to study the temporal and spectral properties of the scattered X-ray emission more accurately with potentially larger dust grains, we provide a practical approach using the series expansions of anomalous diffraction (AD) approximation based on the complicated Mie theory. We apply our calculations to understand the puzzling X-ray afterglow of recently observed GRB 130925A that showed a significant spectral softening. We find that the X-ray scattering scenarios with either AD or RG approximation adopted could well reproduce both the temporal and spectral profile simultaneously. Given the plateau present in the early X-ray light curve, a typical distribution of smaller grains as in the interstellar medium would be suggested for GRB 130925A.

  18. Large-scale Nanostructure Simulations from X-ray Scattering Data On Graphics Processor Clusters

    E-Print Network [OSTI]

    Sarje, Abhinav

    2012-01-01T23:59:59.000Z

    X-ray Scattering Data On Graphics Processor Clusters Abhinavaccelerators. General purpose graphics processors o?er ?nethe form factors on graphics processors. Form Factor Kernel

  19. OBSERBATION OF HIGH INTENSITY X-RAYS IN INVERSE COMPTON SCATTERING EXPERIMENT

    E-Print Network [OSTI]

    OBSERBATION OF HIGH INTENSITY X-RAYS IN INVERSE COMPTON SCATTERING EXPERIMENT S. Kashiwagi, M the first results of high intensity x-ray generation using Inverse Laser Compton scattering. This experiment Synchrotron Source (LSS). It is based on inverse Compton scattering via interaction between pulsed high power

  20. Lipid Bilayer Structure Determined by the Simultaneous Analysis of Neutron and X-Ray Scattering Data

    E-Print Network [OSTI]

    Nagle, John F.

    Lipid Bilayer Structure Determined by the Simultaneous Analysis of Neutron and X-Ray Scattering) and dipalmitoylphosphatidylcholine (DPPC) bilayers by simultaneously analyzing x-ray and neutron scattering data. The neutron data electron and neutron scattering density profiles. A key result of the analysis is the molecular surface

  1. Multi-Scaled Microstructures in Natural Rubber Characterized by Synchrotron X-ray Scattering and Optical Microscopy

    SciTech Connect (OSTI)

    Toki , S.; Hsiao, B; Amnuaypornsri , S; Sakdapipanich, J; Tanaka, Y

    2008-01-01T23:59:59.000Z

    Multi-scaled microstructures induced by natural impurities (i.e., proteins, phospholipids, carbohydrates) in natural rubber (NR) were investigated by synchrotron small-angle X-ray scattering (SAXS), wide-angle X-ray diffraction (WAXD), and optical microscopy using several kinds of untreated and chemically treated un-vulcanized samples. These microstructures include large aggregates (size less than 50 m), well-defined crystals (size less than a few 10 m), and micelles (size much less than 10 m). In un-vulcanized NR samples, even though the concentrations of natural impurities are relatively low, the dispersion of these microstructures significantly affects the mechanical properties

  2. X-ray and Neutron Scattering Studies of Magnetic Domain Dynamics and Spin Structures /

    E-Print Network [OSTI]

    Chen, San-Wen

    2014-01-01T23:59:59.000Z

    Stanley. X-ray and neutron scattering from rough surfaces.1988. [3] R. Pynn. Neutron scattering by rough surfaces at39] V. F. Sears. Neutron scattering lengths and cross

  3. Nuclear resonant inelastic X-ray scattering and synchrotron Mossbauer spectroscopy

    E-Print Network [OSTI]

    Lin, Jung-Fu "Afu"

    Chapter 19 Nuclear resonant inelastic X-ray scattering and synchrotron Mo¨ssbauer spectroscopy with nuclear resonant inelastic X-ray scattering and synchrotron Mo¨ssbauer spectroscopy for studying magnetic to the Planck radiation function. Synchrotron Mo¨ssbauer spectra and partial phonon density of states (PDOS

  4. accurate x-ray scattering: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    is ove... Corrales, Lia 2012-01-01 20 Dust scattering X-ray expanding rings around gamma-ray bursts Astrophysics (arXiv) Summary: Scattering by dust grains in our Galaxy can...

  5. Small-Angle Neutron Scattering Studies of Charged Carboxyl-Terminated Dendrimers in Solutions

    E-Print Network [OSTI]

    Dubin, Paul D.

    Small-Angle Neutron Scattering Studies of Charged Carboxyl-Terminated Dendrimers in Solutions Q. R-angle neutron scattering was used to characterize the solution behavior of charged carboxylic acid terminated- copy,16 small-angle X-ray scattering,17 and small-angle neutron scattering (SANS),18-25 have been used

  6. Protein folding and protein metallocluster studies using synchrotron small angler X-ray scattering

    SciTech Connect (OSTI)

    Eliezer, D.

    1994-06-01T23:59:59.000Z

    Proteins, biological macromolecules composed of amino-acid building blocks, possess unique three dimensional shapes or conformations which are intimately related to their biological function. All of the information necessary to determine this conformation is stored in a protein`s amino acid sequence. The problem of understanding the process by which nature maps protein amino-acid sequences to three-dimensional conformations is known as the protein folding problem, and is one of the central unsolved problems in biophysics today. The possible applications of a solution are broad, ranging from the elucidation of thousands of protein structures to the rational modification and design of protein-based drugs. The scattering of X-rays by matter has long been useful as a tool for the characterization of physical properties of materials, including biological samples. The high photon flux available at synchrotron X-ray sources allows for the measurement of scattering cross-sections of dilute and/or disordered samples. Such measurements do not yield the detailed geometrical information available from crystalline samples, but do allow for lower resolution studies of dynamical processes not observable in the crystalline state. The main focus of the work described here has been the study of the protein folding process using time-resolved small-angle x-ray scattering measurements. The original intention was to observe the decrease in overall size which must accompany the folding of a protein from an extended conformation to its compact native state. Although this process proved too fast for the current time-resolution of the technique, upper bounds were set on the probable compaction times of several small proteins. In addition, an interesting and unexpected process was detected, in which the folding protein passes through an intermediate state which shows a tendency to associate. This state is proposed to be a kinetic molten globule folding intermediate.

  7. Acquisition of an In-House X-ray Scattering Facility for Nanostructure Characterization and Student Training

    SciTech Connect (OSTI)

    Schuller, Ivan K [UC San Diego

    2013-08-02T23:59:59.000Z

    This equipment grant was specifically dedicated to the development of a "state of the art" x-ray scattering facility...

  8. Wide Angle Compton Scattering

    E-Print Network [OSTI]

    Rainer Jakob

    2000-10-16T23:59:59.000Z

    We present the handbag contribution to Wide Angle Compton Scattering (WACS) at moderately large momentum transfer obtained with a proton distribution amplitude close to the asymptotic form. In comparison it is found to be significantly larger than results from the hard scattering (pQCD) approach.

  9. Resonant Soft X-Ray Scattering - Combining Structural with Spectroscop...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    as well as important L-edges of the 3d transition metals important in magnetic and oxide systems. Measurements of soft x-ray absorption spectra are inherently surface sensitive,...

  10. Staff at sector 30, inelastic x-ray scattering

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Sector 30 Staff Advanced Photon Source A U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences national synchrotron x-ray research facility Search Button...

  11. 16th National School on Neutron and X-ray Scattering

    ScienceCinema (OSTI)

    Chakoumakos, Bryan; Achilles, Cherie; Cybulskis, Viktor; Gilbert, Ian

    2014-07-23T23:59:59.000Z

    Students talk about their experience at the 16th National School on Neutron and X-ray Scattering, or NXS 2014. Jointly conducted by Oak Ridge and Argonne national laboratories, NXS immerses graduate students in national user facilities to learn in a hands-on environment how to use neutrons and X-rays in their research.

  12. 16th National School on Neutron and X-ray Scattering

    SciTech Connect (OSTI)

    Chakoumakos, Bryan; Achilles, Cherie; Cybulskis, Viktor; Gilbert, Ian

    2014-07-02T23:59:59.000Z

    Students talk about their experience at the 16th National School on Neutron and X-ray Scattering, or NXS 2014. Jointly conducted by Oak Ridge and Argonne national laboratories, NXS immerses graduate students in national user facilities to learn in a hands-on environment how to use neutrons and X-rays in their research.

  13. High Resolution X-Ray Scattering at Sector 3, Advanced Photon...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    about 1 meV resolution; momentum resolved inelastic x-ray scattering with about 1 meV resolution (HERIX); Synchrotron Mossbauer spectroscopy with about 10 neV resolution (SMS)....

  14. Safety & Security Guidelines Annual U.S. National School on Neutron and X-ray Scattering

    E-Print Network [OSTI]

    Safety & Security Guidelines 15th Annual U.S. National School on Neutron and X-ray Scattering-574-4600. Neutron Sciences User Programs and Outreach Office Oak Ridge National Laboratory #12;

  15. Effects of grazing incidence conditions on the x-ray diffuse scattering from self-assembled nanoscale islands

    SciTech Connect (OSTI)

    Schmidbauer, M.; Grigoriev, D.; Hanke, M.; Schaefer, P.; Wiebach, T.; Koehler, R. [Institut fuer Physik, Humboldt-Universitaet zu Berlin, Newtonstrasse 15, 12489 Berlin (Germany)

    2005-03-15T23:59:59.000Z

    Grazing incidence small-angle x-ray scattering and grazing incidence x-ray diffraction from SiGe nanoscale islands grown on Si(001) substrate were investigated. Experiments and corresponding theoretical simulations based on the distorted-wave Born approximation were carried out. The strain field inside and in the vicinity of the SiGe islands was calculated in the framework of linear elasticity theory using the numerical finite element method. The diffuse intensity pattern in reciprocal space reveals a well-resolved fine structure with prominent maxima and a complicated fringe pattern. The distribution of diffuse intensity in reciprocal space strongly depends on the angle of incidence with respect to the sample surface. The results obtained substantiate the important role of basically five (grazing incidence small-angle x-ray) and nine (grazing incidence diffraction) scattering channels that have to be considered for a complete understanding of the scattering scenario. A refined island model concerning shape, size, and Ge composition was elaborated.

  16. 136 3. Scattering The Compton scattering of an x-ray is incoherent because there are de-

    E-Print Network [OSTI]

    136 3. Scattering The Compton scattering of an x-ray is incoherent because there are de- grees of freedom in each scattering event associated with the atomic electron. Compton scattering provides of an atom are the ones that can participate in Compton scattering because they can be- come unbound from

  17. Observation of pulsed x-ray trains produced by laser-electron Compton scatterings

    SciTech Connect (OSTI)

    Sakaue, Kazuyuki; Washio, Masakazu [Research Institute for Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo 169-8555 (Japan); Araki, Sakae; Fukuda, Masafumi; Higashi, Yasuo; Honda, Yosuke; Omori, Tsunehiko; Taniguchi, Takashi; Terunuma, Nobuhiro; Urakawa, Junji [KEK (High Energy Accelerator Research Organization), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Sasao, Noboru [Department of Physics, Kyoto University, Sakyo, Kyoto 606-8502 (Japan)

    2009-12-15T23:59:59.000Z

    X-ray generation based on laser-electron Compton scattering is one attractive method to achieve a compact laboratory-sized high-brightness x-ray source. We have designed, built, and tested such a source; it combines a 50 MeV multibunch electron linac with a mode-locked 1064 nm laser stored and amplified in a Fabry-Perot optical cavity. We directly observed trains of pulsed x rays using a microchannel plate detector; the resultant yield was found to be 1.2x10{sup 5} Hz in good agreement with prediction. We believe that the result has demonstrated good feasibility of linac-based compact x-ray sources via laser-electron Compton scatterings.

  18. Fabrication of high-throughput critical-angle X-ray transmission gratings for wavelength-dispersive spectroscopy

    E-Print Network [OSTI]

    Bruccoleri, Alexander Robert

    2013-01-01T23:59:59.000Z

    The development of the critical-angle transmission (CAT) grating seeks both an order of magnitude improvement in the effective area, and a factor of three increase in the resolving power of future space-based, soft x-ray ...

  19. Entangled valence electron-hole dynamics revealed by stimulated attosecond x-ray Raman scattering

    SciTech Connect (OSTI)

    Healion, Daniel; Zhang, Yu; Biggs, Jason D.; Govind, Niranjan; Mukamel, Shaul

    2012-09-06T23:59:59.000Z

    We show that broadband x-ray pulses can create wavepackets of valence electrons and holes localized in the vicinity of a selected atom (nitrogen, oxygen or sulfur in cysteine) by resonant stimulated Raman scattering. The subsequent dynamics reveals highly correlated motions of entangled electrons and hole quasiparticles. This information goes beyond the time-dependent total charge density derived from x-ray diffraction.

  20. Demonstration of Successful X-ray Thomson Scattering Using Picosecond K-(alpha) X-ray Sources for the Characterization of Dense Heated Matter

    SciTech Connect (OSTI)

    Kritcher, A; Neumayer, P; Lee, H J; Doeppner, T; Falcone, R; Glenzer, S; Morse, E C

    2008-05-05T23:59:59.000Z

    We discuss the first successful K-{alpha} x-ray Thomson scattering experiment from solid density plasmas for use as a diagnostic in determining the temperature, density, and ionization state of warm dense matter with picosecond resolution. The development of this source as a diagnostic and stringent requirements for successful K-{alpha} x-ray Thomson scattering are addressed. Data for the experimental techniques described in this paper [1] suggest the capability of single shot characterization of warm dense matter and the ability to use this scattering source at future Free Electron Lasers (FEL) where comparable scattering signal levels are predicted.

  1. The 3D-architecture of individual free silver nanoparticles captured by X-ray scattering

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Barke, Ingo; Hartmann, Hannes; Rupp, Daniela; Flückiger, Leonie; Sauppe, Mario; Adolph, Marcus; Schorb, Sebastian; Bostedt, Christoph; Treusch, Rolf; Peltz, Christian; et al

    2015-02-04T23:59:59.000Z

    The diversity of nanoparticle shapes generated by condensation from gaseous matter reflects the fundamental competition between thermodynamic equilibration and the persistence of metastable configurations during growth. In the kinetically limited regime, intermediate geometries that are favoured only in early formation stages can be imprinted in the finally observed ensemble of differently structured specimens. Here we demonstrate that single-shot wide-angle scattering of femtosecond soft X-ray free-electron laser pulses allows three-dimensional characterization of the resulting metastable nanoparticle structures. For individual free ?silver particles, which can be considered frozen in space for the duration of photon exposure, both shape and orientation are uncoveredmore »from measured scattering images. We identify regular shapes, including species with fivefold symmetry and surprisingly large aspect ratio up to particle radii of the order of 100 nm. Our approach includes scattering effects beyond Born’s approximation and is remarkably efficient—opening up new routes in ultrafast nanophysics and free-electron laser science« less

  2. Analysis of Order Formation in Block Copolymer Thin Films UsingResonant Soft X-Ray Scattering

    SciTech Connect (OSTI)

    Virgili, Justin M.; Tao, Yuefei; Kortright, Jeffrey B.; Balsara,Nitash P.; Segalman, Rachel A.

    2006-11-27T23:59:59.000Z

    The lateral order of poly(styrene-block-isoprene) copolymer(PS-b-PI) thin films is characterized by the emerging technique ofresonant soft X-ray scattering (RSOXS) at the carbon K edge and comparedto ordering in bulk samples of the same materials measured usingconventional small-angle X-ray scattering. We show resonance using theoryand experiment that the loss of scattering intensity expected with adecrease in sample volume in the case of thin films can be overcome bytuning X-rays to the pi* resonance of PS or PI. Using RSOXS, we study themicrophase ordering of cylinder- and phere-forming PS-b-PI thin films andcompare these results to position space data obtained by atomic forcemicroscopy. Our ability to examine large sample areas (~;9000 mu m2) byRSOXS enables unambiguous identification of the lateral lattice structurein the thin films. In the case of the sphere-forming copolymer thin film,where the spheres are hexagonally arranged, the average sphere-to-spherespacing is between the bulk (body-centered cubic) nearest neighbor andbulk unit cell spacings. In the case of the cylinder-forming copolymerthin film, the cylinder-to-cylinder spacing is within experimental errorof that obtained in the bulk.

  3. Exact limiting relation between the structure factors in neutron and x-ray scattering

    E-Print Network [OSTI]

    V. B. Bobrov; S. A. Trigger; S. N. Skovorod'ko

    2010-07-11T23:59:59.000Z

    The ratio of the static matter structure factor measured in experiments on coherent X-ray scattering to the static structure factor measured in experiments on neutron scattering is considered. It is shown theoretically that this ratio in the long-wavelength limit is equal to the nucleus charge at arbitrary thermodynamic parameters of a pure substance (the system of nuclei and electrons, where interaction between particles is pure Coulomb) in a disordered equilibrium state. This result is the exact relation of the quantum statistical mechanics. The experimental verification of this relation can be done in the long wavelength X-ray and neutron experiments.

  4. Kevin Yager on the Nanoscience of Studying Scattered X-Rays

    ScienceCinema (OSTI)

    Yager; Kevin

    2014-06-04T23:59:59.000Z

    Kevin Yager, a scientist at Brookhaven Lab's Center for Functional Nanomaterials, discusses his research on materials spanning just billionths of a meter. Yager specializes in making new materials through meticulously guided self-assembly and probing nanoscale structures with a technique called x-ray scattering.

  5. Alamethicin in lipid bilayers: Combined use of X-ray scattering and MD simulations Jianjun Pan a

    E-Print Network [OSTI]

    Nagle, John F.

    Alamethicin in lipid bilayers: Combined use of X-ray scattering and MD simulations Jianjun Pan of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA d Canadian Neutron Beam Centre:1PC with varying amounts of alamethicin (Alm). We combine the use of X-ray diffuse scattering

  6. angle x-ray sky: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Astrophysics (arXiv) Summary: We describe a search for X-ray afterglows from gamma-ray bursts using the ROSAT all-sky survey (RASS) data. If the emission in the soft X-ray...

  7. Pixel array detector for time-resolved x-ray scattering

    SciTech Connect (OSTI)

    Rodricks, B.G. [Argonne National Lab., IL (United States); Barna, S.L.; Gruner, S.M.; Shepherd, J.A.; Tate, M.W.; Wixted, R.L. [Princeton Univ., NJ (United States). Dept. of Physics

    1996-01-01T23:59:59.000Z

    This paper describes the development of a large-area hybrid pixel detector designed for time-resolved synchrotron x-ray scattering experiments where limited frames, with a high framing rate, is required. The final design parameters call for a 1024{times}1O24 pixel array device with 150-micron pixels that is 100% quantum efficient for x-rays with energy up to 20 keV, with a framing rate in the microsecond range. The device will consist of a fully depleted diode array bump bonded to a CMOS electronic storage capacitor array with eight frames per pixel. The two devices may be separated by a x-ray blocking layer that protects the radiation-sensitive electronics layer from damage. The signal is integrated in the electronics layer and stored in one of eight CMOS capacitors. After eight frames are taken, the data are then read out, using clocking electronics external to the detector, and stored in a RAM disk. Results will be presented on the development of a prototype 4{times}4 pixel electronics layer that is capable of storing at least 10,000 12-keV x-ray photons for a capacity of over 50 million electrons with a noise corresponding to 2 x-ray photons per pixel. The diode detective layer, electronics storage layer along with the radiation damage and blocking layers will be discussed.

  8. The diagnostic capability of x-ray scattering parameters for the characterization of breast cancer

    SciTech Connect (OSTI)

    Elshemey, Wael M.; Desouky, Omar S.; Fekry, Mostafa M.; Talaat, Sahar M.; Elsayed, Anwar A. [Department of Biophysics, Faculty of Science, Cairo University, Giza 12613 (Egypt); Department of Radiation Physics, National Centre for Radiation Research and Technology, Madinet Nasr 13759 (Egypt); Department of Biophysics, Faculty of Science, Cairo University, Giza 12613 (Egypt); Department of Pathology, Faculty of Medicine, Cairo University, Cairo 11559 (Egypt); Department of Biophysics, Faculty of Science, Cairo University, Giza 12613 (Egypt)

    2010-08-15T23:59:59.000Z

    Purpose: The evaluation of the diagnostic capability of easy to measure x-ray scattering profile characterization parameters for the detection of breast cancer in excised samples. The selected parameters are the full width at half maximum (FWHM) and area under the x-ray scattering profile of breast tissue in addition to the ratio of scattering intensities (I{sub 2}/I{sub 1}%) at 1.6 nm{sup -1} to that at 1.1 nm{sup -1} (corresponding to scattering from soft and adipose tissues, respectively). Methods: A histopathologist is asked to classify 36 excised breast tissue samples into healthy or malignant. A conventional x-ray diffractometer is used to acquire the scattering profiles of the investigated samples. The values of three profile characterization parameters are calculated and the diagnostic capability of each is evaluated by determining the optimal cutoffs of scatter diagrams, calculating the diagnostic indices, and plotting the receiver operating characteristic (ROC) curves. Results: At the calculated optimal cutoff for each of the examined parameters, the sensitivity ranged from 78% (for area under curve) up to 94% (for FWHM), the specificity ranged from 94%[for I{sub 2}/I{sub 1}% and area under curve] up to 100% (for FWHM), and the diagnostic accuracy ranged from 86% (for area under curve) up to 97% (for FWHM). The area under the ROC curves is greater than 0.95 for all of the investigated parameters, reflecting a highly accurate diagnostic performance. Conclusions: The discussed tests offered a means to quantitatively evaluate the performance of the suggested breast tissue x-ray scattering characterization parameters. The performance results are promising, indicating that the evaluated parameters would be considered a tool for fast, on spot probing of breast cancer in excised tissue samples.

  9. Structure and dynamics of cadmium telluride studied by x-ray and inelastic neutron scattering

    SciTech Connect (OSTI)

    Niedziela, Jennifer L [ORNL; Stone, Matthew B [ORNL

    2014-01-01T23:59:59.000Z

    We present a combined study of density functional theory, x-ray diffraction, and inelastic neutron scattering examining the temperature dependent structure and lattice dynamics of commercially available cadmium telluride. A subtle change in the structure is evinced near 80~K, which manifests also in the measured phonon density of states. There is no change to the long-range ordered structure. The implications of the change in relation to structural defects are discussed.

  10. Structure and dynamics of cadmium telluride studied by x-ray and inelastic neutron scattering

    SciTech Connect (OSTI)

    Niedziela, J. L., E-mail: niedzielajl@ornl.gov [Instrument and Source Division, Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Stone, M. B., E-mail: stonemb@ornl.gov [Quantum Condensed Matter Division, Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

    2014-09-08T23:59:59.000Z

    We present a combined study of density functional theory, x-ray diffraction, and inelastic neutron scattering examining the temperature dependent structure and lattice dynamics of commercially available cadmium telluride. A subtle change in the structure is evinced near 80?K, which manifests also in the measured phonon density of states. There is no change to the long-range ordered structure. The implications of the change in relation to structural defects are discussed.

  11. Maximum entropy deconvolution of resonant inelastic x-ray scattering spectra

    E-Print Network [OSTI]

    J. Laverock; A. R. H. Preston; D. Newby Jr; K. E. Smith; S. B. Dugdale

    2012-02-10T23:59:59.000Z

    Resonant inelastic x-ray scattering (RIXS) has become a powerful tool in the study of the electronic structure of condensed matter. Although the linewidths of many RIXS features are narrow, the experimental broadening can often hamper the identification of spectral features. Here, we show that the Maximum Entropy technique can successfully be applied in the deconvolution of RIXS spectra, improving the interpretation of the loss features without a severe increase in the noise ratio.

  12. Effective Long-Range Attraction between Protein Molecules in Solutions Studied by Small Angle Neutron Scattering

    E-Print Network [OSTI]

    Chen, Sow-Hsin

    Neutron Scattering Yun Liu,1 Emiliano Fratini,2 Piero Baglioni,1,2 Wei-Ren Chen,1 and Sow-Hsin Chen1,* 1, Italy (Received 8 February 2005; published 8 September 2005) Small angle neutron scattering intensity neutron and x-ray scattering investigations of proteins suggest the presence of a short-range attractive

  13. Resonant scattering of an X-ray photon by a heavy atom

    SciTech Connect (OSTI)

    Hopersky, A. N., E-mail: hopersky_vm_1@rgups.ru; Nadolinsky, A. M. [Rostov State University of Transport Communication (Russian Federation)

    2007-10-15T23:59:59.000Z

    The influence of many-body and relativistic effects on the absolute values and shape of the double differential cross section for the resonant scattering of a linearly polarized X-ray photon by a free xenon atom near the K-shell ionization threshold has been theoretically analyzed. The evolution of the spatially extended structure of the scattering cross section to the K{sub {alpha}}{sub ,{beta}} structure of the X-ray spectrum of the xenon atom emission has been demonstrated. The calculations have been performed in the dipole approximation for the anomalous dispersion component of the total inelastic scattering amplitude and in the impulse approximation for the contact component of this amplitude. The contribution of the Rayleigh (elastic) scattering component is taken into account using the methods developed in Hopersky et al., J. Phys. B 30, 5131 (1997). The effects of the radial relaxation of the electron shells, spin-orbit splitting, double excitation/ionization of the atomic ground state, as well as the Auger and radiative decays of the produced main vacancies, are considered. Using the results obtained by Tulkki, Phys. Rev. A 32, 3153 (1985) and Biggs et al., At. Data Nucl. Data Tables 16, 201 (1975), the nonrelativistic Hartree-Fock wavefunctions are changed to the relativistic Dirac-Hartree-Fock wavefunctions of the single-particle scattering states when constructing the process probability amplitude. The calculations are predicting and are in good agreement with the synchrotron experiment on the measurement of the absolute values and shape of the double differential cross section for the resonant scattering of an X-ray photon by a free xenon atom reported by Czerwinski et al., Z. Phys. A 322, 183 (1985)

  14. Scattering Theory When an x-ray beam (or neutron or light) passes through a material with

    E-Print Network [OSTI]

    Beaucage, Gregory

    Scattering Theory When an x-ray beam (or neutron or light) passes through a material radiation is scattered in directions that differ from that of the incident beam. Scattering arises since x of scattered radiation resulting from this process bears a direct relationship to the structure (the pattern

  15. K-alpha X-ray Thomson Scattering From Dense Plasmas

    SciTech Connect (OSTI)

    Kritcher, Andrea L. [Nuclear Engineering Department, University of California Berkeley, Berkeley, CA 94709 (United States); Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94551 (United States); Neumayer, Paul; Castor, John; Doeppner, Tilo; Landen, Otto L.; Ng, Andrew; Pollaine, Steve; Price, Dwight; Glenzer, Siegfried H. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94551 (United States); Falcone, Roger W.; Ja Lee, Hae [Physics Department, University of California Berkeley, Berkeley, CA 94709 (United States); Lee, Richard W. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94551 (United States); Physics Department, University of California Berkeley, Berkeley, CA 94709 (United States); Morse, Edward C. [Nuclear Engineering Department, University of California Berkeley, Berkeley, CA 94709 (United States)

    2009-09-10T23:59:59.000Z

    Spectrally resolved Thomson scattering using ultra-fast K-alpha x rays has measured the compression and heating of shocked compressed matter. The evolution and coalescence of two shock waves traveling through a solid density LiH target were characterized by the elastic scattering component. The density and temperature at shock coalescence, 2.2 eV and 1.7x10{sup 23} cm{sup -3}, were determined from the plasmon frequency shift and the relative intensity of the elastic and inelastic scattering features in the collective scattering regime. The observation of plasmon scattering at coalescence indicates a transition to the dense metallic state in LiH. The density and temperature regimes accessed in these experiments are relevant for inertial confinement fusion experiments and for the study of planetary formation.

  16. The XMM-Newton Wide Angle Survey (XWAS): the X-ray spectrum of type-1 AGN

    E-Print Network [OSTI]

    Mateos, S; Page, M J; Watson, M G; Corral, A; Tedds, J A; Ebrero, J; Krumpe, M; Schwope, A; Ceballos, M T

    2009-01-01T23:59:59.000Z

    We discuss the broad band X-ray properties of one of the largest samples of X-ray selected type-1 AGN to date (487 objects in total), drawn from the XMM-Newton Wide Angle Survey. The objects cover 2-10 keV luminosities from ~10^{42}-10^{45} erg s^{-1} and are detected up to redshift ~4. We constrain the overall properties of the broad band continuum, soft excess and X-ray absorption, along with their dependence on the X-ray luminosity and redshift and we discuss the implications for models of AGN emission. We constrained the mean spectral index of the broad band X-ray continuum to =1.96+-0.02 with intrinsic dispersion sigma=0.27_{-0.02}^{+0.01}. The continuum becomes harder at faint fluxes and at higher redshifts and luminosities. The dependence of Gamma with flux is likely due to undetected absorption rather than to spectral variation. We found a strong dependence of the detection efficiency of objects on the spectral shape which can have a strong impact on the measured mean continuum shapes of sources at di...

  17. Compact x-ray source based on burst-mode inverse Compton scattering at 100 kHz

    E-Print Network [OSTI]

    Bessuille, J.

    A design for a compact x-ray light source (CXLS) with flux and brilliance orders of magnitude beyond existing laboratory scale sources is presented. The source is based on inverse Compton scattering of a high brightness ...

  18. USING THE X-RAY DUST SCATTERING HALO OF CYGNUS X-1 TO DETERMINE DISTANCE AND DUST DISTRIBUTIONS

    E-Print Network [OSTI]

    Xiang, Jingen

    We present a detailed study of the X-ray dust scattering halo of the black hole candidate Cygnus X-1 based on two Chandra High Energy Transmission Gratings Spectrometer observations. Using 18 different dust models, including ...

  19. Attosecond Thomson-scattering x-ray source driven by laser-based electron acceleration

    SciTech Connect (OSTI)

    Luo, W. [School of Nuclear Science and Technology, University of South China, Hengyang 421001 (China) [School of Nuclear Science and Technology, University of South China, Hengyang 421001 (China); College of Science, National University of Defense Technology, Changsha 410073 (China); Zhuo, H. B.; Yu, T. P. [College of Science, National University of Defense Technology, Changsha 410073 (China)] [College of Science, National University of Defense Technology, Changsha 410073 (China); Ma, Y. Y. [College of Science, National University of Defense Technology, Changsha 410073 (China) [College of Science, National University of Defense Technology, Changsha 410073 (China); Applied Ion Beam Physics Laboratory, Institute of Modern Physics, Fudan University, Shanghai 200433 (China); Song, Y. M.; Zhu, Z. C. [School of Nuclear Science and Technology, University of South China, Hengyang 421001 (China)] [School of Nuclear Science and Technology, University of South China, Hengyang 421001 (China); Yu, M. Y. [Department of Physics, Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou 310027 (China) [Department of Physics, Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou 310027 (China); Theoretical Physics I, Ruhr University, D-44801 Bochum (Germany)

    2013-10-21T23:59:59.000Z

    The possibility of producing attosecond x-rays through Thomson scattering of laser light off laser-driven relativistic electron beams is investigated. For a ?200-as, tens-MeV electron bunch produced with laser ponderomotive-force acceleration in a plasma wire, exceeding 10{sup 6} photons/s in the form of ?160 as pulses in the range of 3–300 keV are predicted, with a peak brightness of ?5 × 10{sup 20} photons/(s mm{sup 2} mrad{sup 2} 0.1% bandwidth). Our study suggests that the physical scheme discussed in this work can be used for an ultrafast (attosecond) x-ray source, which is the most beneficial for time-resolved atomic physics, dubbed “attosecond physics.”.

  20. anomalous small-angle x-ray: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    from the soft X-rays emitted by the neutron-star surface. The relation between these heating rates and measured near-infrared fluxes in the K and Ks bands places severe...

  1. Models to analyze small-angle neutron scattering from unilamellar lipid vesicles Norbert Kucerka* and John F. Nagle

    E-Print Network [OSTI]

    Nagle, John F.

    Models to analyze small-angle neutron scattering from unilamellar lipid vesicles Norbert Kucerka from small-angle neutron scattering of unilamellar vesicles. DOI: 10.1103/PhysRevE.69.051903 PACS discrete diffraction peaks that occur for multilamellar arrays, the scattering of x rays or neutrons from

  2. Z .Reviews in Molecular Biotechnology 74 2000 207 231 X-ray and neutron surface scattering for studying

    E-Print Network [OSTI]

    Kuhl, Tonya L.

    Z .Reviews in Molecular Biotechnology 74 2000 207 231 X-ray and neutron surface scattering,U , Tonya L. Kuhlb , Joyce Y. Wongc , Gregory S. Smitha,1 a Manuel Lujan Jr. Neutron Scattering Center is defined as the Zratio of the number of particles neutrons or .photons elastically and specularly scattered

  3. Dynamics of bulk fluctuations in a lamellar phase studied by coherent x-ray scattering

    E-Print Network [OSTI]

    Doru Constantin; Guillaume Brotons; Tim Salditt; Eric Freyssingeas; Anders Madsen

    2015-04-07T23:59:59.000Z

    Using x-ray photon correlation spectroscopy, we studied the layer fluctuations in the lamellar phase of an ionic lyotropic system. We measured the relaxation rate of in-plane (undulation) fluctuations as a function of the wave vector. Static and dynamic results obtained during the same experiment were combined to yield the values of both elastic constants of the lamellar phase (compression and bending moduli) as well as that of the sliding viscosity. The results are in very good agreement with dynamic light-scattering data, validating the use of the technique in ordered phases.

  4. Resonant Soft X-Ray Scattering of Tri-Block Copolymers

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiation Protection TechnicalResonant Soft X-Ray Scattering of Tri-Block Copolymers Print

  5. Resonant Soft X-Ray Scattering of Tri-Block Copolymers

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiation Protection TechnicalResonant Soft X-Ray Scattering of Tri-Block Copolymers

  6. Resonant Soft X-Ray Scattering of Tri-Block Copolymers

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiation Protection TechnicalResonant Soft X-Ray Scattering of Tri-Block

  7. Resonant Soft X-Ray Scattering of Tri-Block Copolymers

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiation Protection TechnicalResonant Soft X-Ray Scattering of Tri-BlockResonant Soft

  8. Resonant Soft X-Ray Scattering of Tri-Block Copolymers

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiation Protection TechnicalResonant Soft X-Ray Scattering of Tri-BlockResonant

  9. Resonant Soft X-Ray Scattering of Tri-Block Copolymers

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiation Protection TechnicalResonant Soft X-Ray Scattering of Tri-BlockResonantResonant

  10. Ultrafast K{alpha} x-ray Thomson scattering from shock compressed lithium hydride

    SciTech Connect (OSTI)

    Kritcher, A. L. [L-399, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551 (United States); Nuclear Engineering Department, University of California Berkeley, Berkeley, California 94709 (United States); Neumayer, P.; Castor, J.; Doeppner, T.; Landen, O. L.; Ng, A.; Pollaine, S.; Price, D.; Glenzer, S. H. [L-399, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551 (United States); Falcone, R. W.; Lee, H. J. [Physics Department, University of California Berkeley, Berkeley, California 94709 (United States); Lee, R. W. [L-399, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551 (United States); Physics Department, University of California Berkeley, Berkeley, California 94709 (United States); Holst, B.; Redmer, R. [Institut fuer Physik, Universitaet Rostock, D-18051 Rostock (Germany); Morse, E. C. [Nuclear Engineering Department, University of California Berkeley, Berkeley, California 94709 (United States)

    2009-05-15T23:59:59.000Z

    Spectrally and temporally resolved x-ray Thomson scattering using ultrafast Ti K{alpha} x rays has provided experimental validation for modeling of the compression and heating of shocked matter. The coalescence of two shocks launched into a solid density LiH target by a shaped 6 ns heater beam was observed from rapid heating to temperatures of 2.2 eV, enabling tests of shock timing models. Here, the temperature evolution of the target at various times during shock progression was characterized from the intensity of the elastic scattering component. The observation of scattering from plasmons, electron plasma oscillations, at shock coalescence indicates a transition to a dense metallic plasma state in LiH. From the frequency shift of the measured plasmon feature the electron density was directly determined with high accuracy, providing a material compression of a factor of 3 times solid density. The quality of data achieved in these experiments demonstrates the capability for single shot dynamic characterization of dense shock compressed matter. The conditions probed in this experiment are relevant for the study of the physics of planetary formation and to characterize inertial confinement fusion targets for experiments such as on the National Ignition Facility, Lawrence Livermore National Laboratory.

  11. Ultrafast K-(alpha) X-ray Thomson Scattering from Shock Compressed Lithium Hydride

    SciTech Connect (OSTI)

    Kritcher, A L; Neumayer, P; Castor, J; Doeppner, T; Falcone, R W; Landen, O L; Lee, H J; Lee, R W; Holst, B; Redmer, R; Morse, E C; Ng, A; Pollaine, S; Price, D; Glenzer, S H

    2008-12-10T23:59:59.000Z

    Spectrally and temporally resolved x ray Thomson scattering using ultrafast Ti K-{alpha} x-rays has provided experimental validation for modeling of the compression and heating of shocked matter. The coalescence of two shocks launched into a solid density LiH target by a shaped 6 nanosecond heater beam was observed from rapid heating to temperatures of 2.2 eV, enabling tests of shock timing models. Here, the temperature evolution of the target at various times during shock progression was characterized from the intensity of the elastic scattering component. The observation of scattering from plasmons, electron plasma oscillations, at shock coalescence indicates a transition to a dense metallic plasma state in LiH. From the frequency shift of the measured plasmon feature the electron density was directly determined with high accuracy, providing a material compression of a factor of three times solid density. The quality of data achieved in these experiments demonstrates the capability for single-shot dynamic characterization of dense shock compressed matter. The conditions probed in this experiment are relevant for the study of the physics of planetary formation and to characterize inertial confinement fusion targets for experiments such as on the National Ignition Facility (NIF), LLNL.

  12. Simultaneous measurements of several state variables in shocked carbon by imaging x-ray scattering

    SciTech Connect (OSTI)

    Gamboa, E. J., E-mail: eliseo@umich.edu; Drake, R. P.; Keiter, P. A.; Trantham, M. R. [University of Michigan, Ann Arbor, Michigan 48109 (United States)] [University of Michigan, Ann Arbor, Michigan 48109 (United States); Falk, K.; Montgomery, D. S.; Benage, J. F. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2014-04-15T23:59:59.000Z

    We apply the novel experimental technique of imaging x-ray Thomson scattering to measure the spatial profiles of the temperature, ionization state, relative material density, and the shock speed in a high-energy density system. A blast wave driven in a low-density foam is probed with 90? scattering of 7.8?keV helium-like nickel x-rays, which are spectrally dispersed and resolved in one spatial dimension by a doubly curved crystal. The inferred properties of the shock are shown to be self-consistent with 1D analytical estimates. These high-resolution measurements enable a direct comparison of the observed temperature with the results from hydrodynamic simulations. We find good agreement with the simulations for the temperature at the shock front but discrepancies in the modeling of the spatial temperature profile and shock speed. These results indicate the challenges in modeling the shock dynamics of structured materials like foams, commonly used in many high-energy density and laboratory astrophysics experiments.

  13. Resonant Soft X-ray Scattering Studies of Multiferroic YMn2O5

    SciTech Connect (OSTI)

    Partzsch, S.; Wilkins, S.B.; Schierle, E.; Soltwisch, V.; Hill, J.P.; Weschke, E.; Souptel, D.; Buchner, B.; Geck, J.

    2011-06-17T23:59:59.000Z

    We performed soft x-ray resonant scattering at the MnL{sub 2,3}- and OK edges of YMn{sub 2}O{sub 5}. While the resonant intensity at the MnL{sub 2,3} edges represent the magnetic order parameter, the resonant scattering at the OK edge is found to be directly related to the macroscopic ferroelectric polarization. The latter observation reveals the important role of the spin-dependent Mn-O hybridization for the multiferroicity of YMn{sub 2}O{sub 5}. We present details about how to obtain correct energy dependent lineshapes and discuss the origin of the resonant intensity at the OK edge.

  14. Supplementary data for HIV-1 Tat membrane interaction probed using X-ray and neutron scattering, CD, and MD simulations

    E-Print Network [OSTI]

    Nagle, John F.

    1 Supplementary data for HIV-1 Tat membrane interaction probed using X-ray and neutron scattering- spacing are linearly related. Figure S3. Neutron scattering from stacks of DOPC:DOPE (3:1)/Tat, x=0 of Physics, Rensselaer Polytechnic Institute, 110 Eighth Street, Troy, NY 12180, 3 NIST Center for Neutron

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

    SciTech Connect (OSTI)

    Devloo-Casier, Kilian, E-mail: Kilian.DevlooCasier@Ugent.be; Detavernier, Christophe; Dendooven, Jolien [Department of Solid State Sciences, Ghent University, Krijgslaan 281/S1, B-9000 Ghent (Belgium); Ludwig, Karl F. [Physics Department, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215 (United States)

    2014-01-15T23:59:59.000Z

    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.

  16. X-Ray Interactions with Matter from the Center for X-Ray Optics (CXRO)

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Henke, B.L.; Gullikson, E.M.; Davis, J.C.

    The primary interactions of low-energy x-rays within condensed matter, viz. photoabsorption and coherent scattering, are described for photon energies outside the absorption threshold regions by using atomic scattering factors. The atomic scattering factors may be accurately determined from the atomic photoabsorption cross sections using modified Kramers-Kronig dispersion relations. From a synthesis of the currently available experimental data and recent theoretical calculations for photoabsorption, the angle-independent, forward-scattering components of the atomic scattering factors have been thus semiempirically determined and tabulated here for 92 elements and for the region 50-30,000 eV. Atomic scattering factors for all angles of coherent scattering and at the higher photon energies are obtained from these tabulated forward-scattering values by adding a simple angle-dependent form-factor correction. The incoherent scattering contributions that become significant for the light elements at the higher photon energies are similarly determined. The basic x-ray interaction relations that are used in applied x-ray physics are presented here in terms of the atomic scattering factors. The bulk optical constants are also related to the atomic scattering factors. These atomic and optical relations are applied to the detailed calculation of the reflectivity characteristics of a series of practical x-ray mirror, multilayer, and crystal monochromators. Comparisons of the results of this semiempirical,"atom-like", description of x-ray interactions for the low-energy region with those of experiment and ab initio theory are presented.

  17. Measuring the mean and scatter of the X-ray luminosity -- optical richness relation for maxBCG galaxy clusters

    E-Print Network [OSTI]

    E. S. Rykoff; T. A. McKay; M. R. Becker; A. Evrard; D. E. Johnston; B. P. Koester; E. Rozo; E. S. Sheldon; R. H. Wechsler

    2007-12-05T23:59:59.000Z

    Determining the scaling relations between galaxy cluster observables requires large samples of uniformly observed clusters. We measure the mean X-ray luminosity--optical richness (L_X--N_200) relation for an approximately volume-limited sample of more than 17,000 optically-selected clusters from the maxBCG catalog spanning the redshift range 0.1X-ray emission from many clusters using ROSAT All-Sky Survey data, we are able to measure mean X-ray luminosities to ~10% (including systematic errors) for clusters in nine independent optical richness bins. In addition, we are able to crudely measure individual X-ray emission from ~800 of the richest clusters. Assuming a log-normal form for the scatter in the L_X--N_200 relation, we measure \\sigma_\\ln{L}=0.86+/-0.03 at fixed N_200. This scatter is large enough to significantly bias the mean stacked relation. The corrected median relation can be parameterized by L_X = (e^\\alpha)(N_200/40)^\\beta 10^42 h^-2 ergs/s, where \\alpha = 3.57+/-0.08 and \\beta = 1.82+/-0.05. We find that X-ray selected clusters are significantly brighter than optically-selected clusters at a given optical richness. This selection bias explains the apparently X-ray underluminous nature of optically-selected cluster catalogs.

  18. Flat panel X-ray detector with reduced internal scattering for improved attenuation accuracy and dynamic range

    DOE Patents [OSTI]

    Smith, Peter D. (Santa Fe, NM); Claytor, Thomas N. (White Rock, NM); Berry, Phillip C. (Albuquerque, NM); Hills, Charles R. (Los Alamos, NM)

    2010-10-12T23:59:59.000Z

    An x-ray detector is disclosed that has had all unnecessary material removed from the x-ray beam path, and all of the remaining material in the beam path made as light and as low in atomic number as possible. The resulting detector is essentially transparent to x-rays and, thus, has greatly reduced internal scatter. The result of this is that x-ray attenuation data measured for the object under examination are much more accurate and have an increased dynamic range. The benefits of this improvement are that beam hardening corrections can be made accurately, that computed tomography reconstructions can be used for quantitative determination of material properties including density and atomic number, and that lower exposures may be possible as a result of the increased dynamic range.

  19. National School on Neutron and X-ray Scattering Building 223 Auditorium, Room B002 September 24 -October 11, 2008 Argonne National Laboratory

    E-Print Network [OSTI]

    Pennycook, Steve

    National School on Neutron and X-ray Scattering Building 223 Auditorium, Room B002 September 24 (HFIR) Neutron Scattering Science Division Oak Ridge Laboratory 10:15 - 10:30 Break 9:30 - 9:45 Break 10 School on Neutron and X-ray Scattering Building 8600, Main Lobby September 24 - October 11, 2008 Oak

  20. Ultra-high Resolution Optics for EUV and Soft X-ray Inelastic Scattering

    E-Print Network [OSTI]

    Voronov, Dmitry L.

    2010-01-01T23:59:59.000Z

    16. Yu. Shvyd’ko, X-Ray Optics, Berlin: Springer-Verlag,Ultra-high Resolution Optics for EUV and Soft X-rayspectral resolution soft x-ray optics. Conventionally in the

  1. Changes in the Atomic Structure through Glass Transition Observed by X-Ray Scattering

    SciTech Connect (OSTI)

    Egami, Takeshi [ORNL

    2012-01-01T23:59:59.000Z

    The glass transition involves a minor change in the internal energy, and yet the physical and mechanical properties of a glass change dramatically. In order to determine the evolution of the atomic structure through the glass transition, we employed in-situ synchrotron X-ray scattering measurements as a function of temperature on a model material: Zr-Cu-Al metallic glass. We found that the thermal expansion at the atomic level is smaller than the macroscopic thermal expansion, and significantly increases above the glass transition temperature. The observed changes in the pair-distribution function (PDF) are explained in terms of the fluctuations in the local atomic volume and their change through the glass transition.

  2. Ultra-fast x-ray Thomson scattering measurements of coalescing shock-heated matter

    SciTech Connect (OSTI)

    Kritcher, A; Neumayer, P; Castor, J; Doppner, T; Falcone, R W; Landen, O L; Lee, H J; Lee, R W; Morse, E C; Ng, A; Pollaine, S; Price, D; Glenzer, S H

    2008-05-29T23:59:59.000Z

    The experiment in this work was preformed at the Titan laser facility (S1) where a short pulse beam at a wavelength of 1053nm delivered up to 350J in 0.5 to 20 ps and a long pulse beam at 527nm, 2{omega} frequency provided energies up to 450J in 1 to 6 ns. Long pulse shaping in this experiment, similar to future capabilities at NIF, was primarily a 4ns long foot with an intensity of 1 x 10{sup 13} W/cm{sup 2}, followed by a 2ns long peak with an intensity of 3 x 10{sup 13} W/cm{sup 2}. A {approx} 600 um phase plate was used on the long pulse beam to moderate non-uniformities in the intensity profile. An illustration of the Thomson scattering setup for this experiment is provided in Fig. 1 of the main text. A nearly mono-energetic scattering source of {Delta}E/E {approx} 0.3% in the 4.5 keV Ti K-alpha line was produced via intense short-pulse laser irradiation of 1.9 x 3 x 0.01 mm Ti foils, creating energetic keV electrons in the process (S2, S3). The nearly isotropic source emission (S4) is produced in the cold solid density bulk of the foil from electron K shell ionization of neutral or weakly ionized atoms, with an emission size on the order of the laser focal spot. By optimizing the laser intensity and pulse width to 4.4 x 10{sup 16} W cm{sup -2}, a total of 2.3 x 10{sup 13} x-ray photons have been produced into 4{pi}. This value corresponds to a conversion efficiency of laser energy into Ti K-alpha x-ray energy of 5 x 10{sup -5}, see Fig. S1. These sources provide {approx}10 ps x-ray pulses as measured experimentally (S5).

  3. Morphology of gold nanoparticles determined by full-curve fitting of the light absorption spectrum. Comparison with X-ray scattering and electron microscopy data

    E-Print Network [OSTI]

    Kostyantyn Slyusarenko; Benjamin Abécassis; Patrick Davidson; Doru Constantin

    2015-04-04T23:59:59.000Z

    UV-Vis absorption spectroscopy is frequently used to characterize the size and shape of gold nanoparticles. We present a full-spectrum model that yields reliable results for the commonly encountered case of mixtures of spheres and rods in varying proportions. We determine the volume fractions of the two populations, the aspect ratio distribution of the nanorods (average value and variance) and the interface damping parameter. We validate the model by checking the fit results against small-angle X-ray scattering and transmission electron microscopy data and show that correctly accounting for the polydispersity in aspect ratio is essential for a quantitative description of the longitudinal plasmon peak.

  4. X-ray resonant magnetic scattering and x-ray magnetic circular dichroism branching ratios, L[subscript 3] / L[subscript 2], for heavy rare earths

    SciTech Connect (OSTI)

    Lee, Yongbin; Kim, Jong-Woo; Goldman, Alan I.; Harmon, Bruce N. (Iowa State)

    2010-07-19T23:59:59.000Z

    In this study we have used first principles electronic structure methods to investigate the detailed contributions to the L{sub 3}/L{sub 2} branching ratio in the heavy rare earth elements. The calculations use the full potential, relativistic, linear augmented plane wave method with the LSDA+U approach for consideration of the local 4f electronic orbitals. With no spin orbit coupling (SOC) in the conducting bands, and with the same radial function for the 2p{sub 3/2} and 2p{sub 1/2} core states, the branching ratio (BR) is exactly 1:-1 for the x-ray magnetic circular dichroism spectra of the ferromagnetic heavy rare earth metals. However, with full SOC the BR ranges from 1.5 to 6.0 in going from Gd to Er. The energy and spin dependence of the 5d radial functions are important. The results point to problems with modified atomic models which have been proposed to explain the BR. Recent x-ray resonant magentic scattering experiments on (Gd,Tb,Dy,Ho,Er,Tm)Ni{sub 2}Ge{sub 2} are discussed.

  5. Large angle solid state position sensitive x-ray detector system

    DOE Patents [OSTI]

    Kurtz, D.S.; Ruud, C.O.

    1998-07-21T23:59:59.000Z

    A method and apparatus are disclosed for x-ray measurement of certain properties of a solid material. In distinction to known methods and apparatus, this invention employs a specific fiber-optic bundle configuration, termed a reorganizer, itself known for other uses, for coherently transmitting visible light originating from the scintillation of diffracted x-radiation from the solid material gathered along a substantially one dimensional linear arc, to a two-dimensional photo-sensor array. The two-dimensional photodetector array, with its many closely packed light sensitive pixels, is employed to process the information contained in the diffracted radiation and present the information in the form of a conventional x-ray diffraction spectrum. By this arrangement, the angular range of the combined detector faces may be increased without loss of angular resolution. Further, the prohibitively expensive coupling together of a large number of individual linear diode photodetectors, which would be required to process signals generated by the diffracted radiation, is avoided. 7 figs.

  6. Large angle solid state position sensitive x-ray detector system

    DOE Patents [OSTI]

    Kurtz, David S. (State College, PA); Ruud, Clay O. (State College, PA)

    1998-01-01T23:59:59.000Z

    A method and apparatus for x-ray measurement of certain properties of a solid material. In distinction to known methods and apparatus, this invention employs a specific fiber-optic bundle configuration, termed a reorganizer, itself known for other uses, for coherently transmitting visible light originating from the scintillation of diffracted x-radiation from the solid material gathered along a substantially one dimensional linear arc, to a two-dimensional photo-sensor array. The two-dimensional photodetector array, with its many closely packed light sensitive pixels, is employed to process the information contained in the diffracted radiation and present the information in the form of a conventional x-ray diffraction spectrum. By this arrangement, the angular range of the combined detector faces may be increased without loss of angular resolution. Further, the prohibitively expensive coupling together of a large number of individual linear diode photodetectors, which would be required to process signals generated by the diffracted radiation, is avoided.

  7. Large angle solid state position sensitive x-ray detector system

    DOE Patents [OSTI]

    Kurtz, D.S.; Ruud, C.O.

    1998-03-03T23:59:59.000Z

    A method and apparatus for x-ray measurement of certain properties of a solid material are disclosed. In distinction to known methods and apparatus, this invention employs a specific fiber-optic bundle configuration, termed a reorganizer, itself known for other uses, for coherently transmitting visible light originating from the scintillation of diffracted x-radiation from the solid material gathered along a substantially one dimensional linear arc, to a two-dimensional photo-sensor array. The two-dimensional photodetector array, with its many closely packed light sensitive pixels, is employed to process the information contained in the diffracted radiation and present the information in the form of a conventional x-ray diffraction spectrum. By this arrangement, the angular range of the combined detector faces may be increased without loss of angular resolution. Further, the prohibitively expensive coupling together of a large number of individual linear diode photodetectors, which would be required to process signals generated by the diffracted radiation, is avoided. 7 figs.

  8. National School on Neutron and X-ray Scattering Oak Ridge National Laboratory and Argonne National Laboratory

    E-Print Network [OSTI]

    Pennycook, Steve

    National School on Neutron and X-ray Scattering Oak Ridge National Laboratory and Argonne National Laboratory May 30-June 14, 2009 Air Travel Arrangements The Argonne Division of Educational Programs has made to Argonne - June 8 through and including June 13, 2009 Daily bus transportation will be provided for School

  9. National School on Neutron and X-ray Scattering Argonne National Laboratory and Oak Ridge National Laboratory

    E-Print Network [OSTI]

    Pennycook, Steve

    National School on Neutron and X-ray Scattering Argonne National Laboratory and Oak Ridge National Laboratory June 12-26, 2010 Schedule for Saturday, June 12, 2010 School participants arrive at Argonne and check in at the Argonne Guest House, Building 460. 3:00 PM until 8:00 PM - Registration and informal get

  10. National School on Neutron and X-ray Scattering Oak Ridge National Laboratory and Argonne National Laboratory

    E-Print Network [OSTI]

    National School on Neutron and X-ray Scattering Oak Ridge National Laboratory and Argonne National Laboratory June 11-25, 2011 Air Travel Arrangements The Argonne Division of Educational Programs has made at the Argonne Guest House at approximately 6:00 p.m. (CDT). Dinner will be provided upon arrival to the hotel

  11. Neutron and X-ray Scattering Techniques have proved so successful in condensed matter studies that a wide variety of sample environments have been developed in consquence. Many

    E-Print Network [OSTI]

    Boyer, Edmond

    Foreword Neutron and X-ray Scattering Techniques have proved so successful in condensed matter whose function is to develop and optimise the techniques appropriate to neutron scattering. Since other neutron and X-ray research centres have similar technical support groups, it was felt timely to unité

  12. Relaxation transition in glass-forming polybutadiene as revealed by nuclear resonance X-ray scattering

    SciTech Connect (OSTI)

    Kanaya, Toshiji; Inoue, Rintaro [Institute for Chemical Research, Kyoto University, Uji, Kyoto-fu 611-0011 (Japan)] [Institute for Chemical Research, Kyoto University, Uji, Kyoto-fu 611-0011 (Japan); Saito, Makina [Elettra-Sincrotrone Trieste, S. S. 14 Km 163.5, I-34149 Trieste (Italy)] [Elettra-Sincrotrone Trieste, S. S. 14 Km 163.5, I-34149 Trieste (Italy); Seto, Makoto [Research Reactor Institute, Kyoto University, Kumatori, Osaka-fu 590-0494 (Japan)] [Research Reactor Institute, Kyoto University, Kumatori, Osaka-fu 590-0494 (Japan); Yoda, Yoshitaka [Japan Synchrotron Radiation Research Institute, Sayo, Hyogo-ken 679-5198 (Japan)] [Japan Synchrotron Radiation Research Institute, Sayo, Hyogo-ken 679-5198 (Japan)

    2014-04-14T23:59:59.000Z

    We investigated the arrest mechanism of molecular motions in a glass forming polybutadiene near the glass transition using a new nuclear resonance synchrotron X-ray scattering technique to cover a wide time range (10{sup ?9} to 10{sup ?5} s) and a scattering vector Q range (9.6–40 nm{sup ?1}), which have never been accessed by other methods. Owing to the wide time and Q ranges it was found for the first time that a transition of the ?-process to the slow ?-process (or the Johari-Goldstein process) was observed in a Q range higher than the first peak in the structure factor S(Q) at the critical temperature T{sub c} in the mode coupling theory. The results suggest the important roles of hopping motions below T{sub c}, which was predicted by the recent extended mode coupling theory and the cooperative motions due to the strong correlation at the first peak in S(Q) in the arrest mechanism.

  13. Concept to diagnose mix with imaging x-ray Thomson scattering

    SciTech Connect (OSTI)

    Keiter, Paul A.; Gamboa, Eliseo J.; Huntington, Channing M.; Kuranz, Carolyn C. [Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, Ann Arbor, Michigan 48103 (United States)

    2012-10-15T23:59:59.000Z

    Turbulent mixing of two fluid species is a ubiquitous problem, prevalent in systems such as inertial confinement fusion (ICF) capsule implosions, supernova remnants, and other astrophysical systems. In complex, high Reynolds number compressible high energy density (HED) flows such as these, hydrodynamic instabilities initiate the turbulent mixing process, which can then feedback and alter the mean hydrodynamic motion through nonlinear processes. In order to predict how these systems evolve under turbulent conditions, models are used. However, these models require detailed quantitative data to validate and constrain their detailed physics models as well as improve them. Providing this much needed data is currently at the forefront of HED research but is proving elusive due to a lack of available diagnostics capable of directly measuring detailed flow variables. Thomson scattering is a promising technique in this regard as it provides fundamental conditions of the flow ({rho}, T, Zbar) due to its direct interaction with the small scales of the fluid or plasma and was recently considered as a possible mix diagnostic. With the development of imaging x-ray Thomson scattering (IXRTS) obtaining spatial profiles of these variables is within reach. We propose a novel use of the IXRTS technique that will provide more detailed quantitative data required for model validation in mix experiments.

  14. Nucleation and Ordering of an Electrodeposited Two-Dimensional Crystal: Real-Time X-Ray Scattering and Electronic Measurements

    SciTech Connect (OSTI)

    Finnefrock, A.C.; Ringland, K.L.; Brock, J.D. [School of Applied Engineering Physics and Materials Science Center, Cornell University, Ithaca, New York 14853 (United States)] [School of Applied Engineering Physics and Materials Science Center, Cornell University, Ithaca, New York 14853 (United States); Buller, L.J.; Abruna, H.D. [Department of Chemistry and Materials Science Center, Cornell University, Ithaca, New York 14853 (United States)] [Department of Chemistry and Materials Science Center, Cornell University, Ithaca, New York 14853 (United States)

    1998-10-01T23:59:59.000Z

    We have studied {ital in situ} the ordering of a two-dimensional Cu-Cl crystal electrodeposited on a Pt(111) surface. We simultaneously measured x-ray scattering and chronoamperometric transients during Cu desorption and subsequent ordering of the Cu-Cl crystal. In all cases, the current transient occurs on a shorter time scale than the development of crystalline order. The ordering time diverges with applied potential, consistent with the nucleation and growth of two-dimensional islands. We see a time-dependent narrowing of the x-ray peak, corresponding to the growing islands. {copyright} {ital 1998} {ital The American Physical Society}

  15. Narrowband inverse Compton scattering x-ray sources at high laser intensities

    E-Print Network [OSTI]

    Seipt, D; Surzhykov, A; Fritzsche, S

    2014-01-01T23:59:59.000Z

    Narrowband x- and gamma-ray sources based on the inverse Compton scattering of laser pulses suffer from a limitation of the allowed laser intensity due to the onset of nonlinear effects that increase their bandwidth. It has been suggested that laser pulses with a suitable frequency modulation could compensate this ponderomotive broadening and reduce the bandwidth of the spectral lines, which would allow to operate narrowband Compton sources in the high-intensity regime. In this paper we, therefore, present the theory of nonlinear Compton scattering in a frequency modulated intense laser pulse. We systematically derive the optimal frequency modulation of the laser pulse from the scattering matrix element of nonlinear Compton scattering, taking into account the electron spin and recoil. We show that, for some particular scattering angle, an optimized frequency modulation completely cancels the ponderomotive broadening for all harmonics of the backscattered light. We also explore how sensitive this compensation ...

  16. Using synchrotron X-ray scattering to study the diffusion of water in a weakly-hydrated clay sample

    E-Print Network [OSTI]

    Y. Meheust; B. Sandnes; G. Lovoll; K. J. Maloy; J. O. Fossum; G. J. da Silva; M. S. P. Mundim; R. Droppa; D. d. Miranda Fonseca

    2005-09-10T23:59:59.000Z

    We study the diffusion of water in weakly-hydrated samples of the smectite clay Na-fluorohectorite. The quasi one-dimensional samples are dry compounds of nano-layered particles consisting of ~ 80 silicate platelets. Water diffuses into a sample through the mesoporosity in between the particles, and can subsequently intercalate into the adjacent particles. The samples are placed under controlled temperature. They are initially under low humidity conditions, with all particles in a 1WL intercalation state. We then impose a high humidity at one sample end, triggering water penetration along the sample length. We monitor the progression of the humidity front by monitoring the intercalation state of the particles in space and time. This is done by determining the characteristic spacing of the nano-layered particles in situ, from synchrotron wide-angle X-ray scattering measurements. The spatial width of the intercalation front is observed to be smaller than 2mm, while its velocity decreases with time, as expected from a diffusion process.

  17. Realizing in-plane surface diffraction by x-ray multiple-beam diffraction with large incidence angle

    SciTech Connect (OSTI)

    Huang, Xian-Rong, E-mail: xiahuang@aps.anl.gov; Gog, Thomas; Assoufid, Lahsen [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Peng, Ru-Wen, E-mail: rwpeng@nju.edu.cn [National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093 (China); Siddons, D. P. [National Synchrotron Light Source, Brookhaven National Laboratory, Upton, New York 11973 (United States)

    2014-11-03T23:59:59.000Z

    Based on rigorous dynamical-theory calculations, we demonstrate the principle of an x-ray multiple-beam diffraction (MBD) scheme that overcomes the long-lasting difficulties of high-resolution in-plane diffraction from crystal surfaces. This scheme only utilizes symmetric reflection geometry with large incident angles but activates the out-of-plane and in-plane diffraction processes simultaneously and separately in the continuous MBD planes. The in-plane diffraction is realized by detoured MBD, where the intermediate diffracted waves propagate parallel to the surface, which corresponds to an absolute Bragg surface diffraction configuration that is extremely sensitive to surface structures. A series of MBD diffraction and imaging techniques may be developed from this principle to study surface/interface (misfit) strains, lateral nanostructures, and phase transitions of a wide range of (pseudo)cubic crystal structures, including ultrathin epitaxial films and multilayers, quantum dots, strain-engineered semiconductor or (multi)ferroic materials, etc.

  18. Profiling nitrogen in ultrathin silicon oxynitrides with angle-resolved x-ray photoelectron spectroscopy

    E-Print Network [OSTI]

    Gustafsson, Torgny

    medium energy ion scattering and secondary ion mass spectrometry analysis. Preferential nitrogen by low energy ion (15 N2) implantation. The nitrogen profile and nitrogen chemical bonding states only minor in- crease in the dielectric constant compared to SiO2 but is still favored over other high

  19. Qualification of a high-efficiency, gated spectrometer for x-ray Thomson scattering on the National Ignition Facility

    SciTech Connect (OSTI)

    Döppner, T.; Kritcher, A. L.; Bachmann, B.; Burns, S.; Hawreliak, J.; House, A.; Landen, O. L.; LePape, S.; Ma, T.; Pak, A.; Swift, D. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Neumayer, P. [Gesellschaft für Schwerionenphysik, 64291 Darmstadt (Germany); Kraus, D. [University of California, Berkeley, California 94720 (United States); Falcone, R. W. [University of California, Berkeley, California 94720 (United States); Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Glenzer, S. H. [SLAC National Accelerator Laboratory, Menlo Park, California 94309 (United States)

    2014-11-15T23:59:59.000Z

    We have designed, built, and successfully fielded a highly efficient and gated Bragg crystal spectrometer for x-ray Thomson scattering measurements on the National Ignition Facility (NIF). It utilizes a cylindrically curved Highly Oriented Pyrolytic Graphite crystal. Its spectral range of 7.4–10?keV is optimized for scattering experiments using a Zn He-? x-ray probe at 9.0 keV or Mo K-shell line emission around 18 keV in second diffraction order. The spectrometer has been designed as a diagnostic instrument manipulator-based instrument for the NIF target chamber at the Lawrence Livermore National Laboratory, USA. Here, we report on details of the spectrometer snout, its novel debris shield configuration and an in situ spectral calibration experiment with a Brass foil target, which demonstrated a spectral resolution of E/?E = 220 at 9.8 keV.

  20. anomalous x-ray scattering: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    from the soft X-rays emitted by the neutron-star surface. The relation between these heating rates and measured near-infrared fluxes in the K and Ks bands places severe...

  1. Resonant Soft X-Ray Scattering of Tri-Block Copolymers

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    the importance of RSoXS as a unique, powerful tool for examining complex, multi-component systems that could not be characterized with conventional methods. An X-Ray Probe for Soft...

  2. Neutron and x-ray scattering studies of the metallurgical condition and residual stresses in Weldalite welds

    SciTech Connect (OSTI)

    Spooner, S. [Oak Ridge National Lab., TN (United States); Pardue, E.B.S. [Technology for Energy Corp., Knoxville, TN (United States)

    1995-12-31T23:59:59.000Z

    Weldalite is a lithium-containing aluminum alloy which is being considered for aerospace applications because its favorable strength-to-weight ratio. Successful welding of this alloy depends on the control of the metallurgical condition and residual stresses in the heat affected zone. Neutron and x-ray scattering methods of residual stress measurement were applied to plasma arc welds made in aluminum-lithium alloy test panels as part of an evaluation of materials for use in welded structures. In the course of these studies discrepancies between x-ray and neutron results from the heat affected zone (HAZ) of the weld were found. Texture changes and recovery from the cold work, indicated in peak widths, were found in the HAZ as well. The consideration of x-ray and neutron results leads to the conclusion that there is a change in solute composition which modifies the d-spacings in the HAZ which affects the neutron diffraction determination of residual stresses. The composition changes give the appearance of significant compressive strains in the HAZ. This effect and sharp gradients in the texture give severe anomalies in the neutron measurement of residual stress. The use of combined x-ray and neutron techniques and the solution to the minimizing of the neutron diffraction anomalies are discussed.

  3. Ion distributions at charged aqueous surfaces: Synchrotron X-ray scattering studies

    SciTech Connect (OSTI)

    Bu, Wei

    2009-08-15T23:59:59.000Z

    Surface sensitive synchrotron X-ray scattering studies were performed to obtain the distribution of monovalent ions next to a highly charged interface at room temperature. To control surface charge density, lipids, dihexadecyl hydrogen-phosphate (DHDP) and dimysteroyl phosphatidic acid (DMPA), were spread as monolayer materials at the air/water interface, containing CsI at various concentrations. Five decades in bulk concentrations (CsI) are investigated, demonstrating that the interfacial distribution is strongly dependent on bulk concentration. We show that this is due to the strong binding constant of hydronium H3O+ to the phosphate group, leading to proton-transfer back to the phosphate group and to a reduced surface charge. Using anomalous reflectivity off and at the L3 Cs+ resonance, we provide spatial counterion (Cs+) distributions next to the negatively charged interfaces. The experimental ion distributions are in excellent agreement with a renormalized surface charge Poisson-Boltzmann theory for monovalent ions without fitting parameters or additional assumptions. Energy Scans at four fixed momentum transfers under specular reflectivity conditions near the Cs+ L3 resonance were conducted on 10-3 M CsI with DHDP monolayer materials on the surface. The energy scans exhibit a periodic dependence on photon momentum transfer. The ion distributions obtained from the analysis are in excellent agreement with those obtained from anomalous reflectivity measurements, providing further confirmation to the validity of the renormalized surface charge Poisson-Boltzmann theory for monovalent ions. Moreover, the dispersion corrections f0 and f00 for Cs+ around L3 resonance, revealing the local environment of a Cs+ ion in the solution at the interface, were extracted simultaneously with output of ion distributions.

  4. BioSAXS Sample Changer: a robotic sample changer for rapid and reliable high-throughput X-ray solution scattering experiments

    SciTech Connect (OSTI)

    Round, Adam, E-mail: around@embl.fr; Felisaz, Franck [European Molecular Biology Laboratory, Grenoble Outstation, 71 Avenue des Martyrs, CS 90181, 38042 Grenoble (France); Université Grenoble Alpes–EMBL–CNRS, 71 Avenue des Martyrs, CS 90181, 38042 Grenoble (France); Fodinger, Lukas; Gobbo, Alexandre [European Molecular Biology Laboratory, Grenoble Outstation, 71 Avenue des Martyrs, CS 90181, 38042 Grenoble (France); Huet, Julien [European Molecular Biology Laboratory, Grenoble Outstation, 71 Avenue des Martyrs, CS 90181, 38042 Grenoble (France); Université Grenoble Alpes–EMBL–CNRS, 71 Avenue des Martyrs, CS 90181, 38042 Grenoble (France); Villard, Cyril [European Molecular Biology Laboratory, Grenoble Outstation, 71 Avenue des Martyrs, CS 90181, 38042 Grenoble (France); Blanchet, Clement E., E-mail: around@embl.fr [EMBL c/o DESY, Notkestrasse 85, 22603 Hamburg (Germany); Pernot, Petra; McSweeney, Sean [ESRF, 6 Rue Jules Horowitz, 38000 Grenoble (France); Roessle, Manfred; Svergun, Dmitri I. [EMBL c/o DESY, Notkestrasse 85, 22603 Hamburg (Germany); Cipriani, Florent, E-mail: around@embl.fr [European Molecular Biology Laboratory, Grenoble Outstation, 71 Avenue des Martyrs, CS 90181, 38042 Grenoble (France); Université Grenoble Alpes–EMBL–CNRS, 71 Avenue des Martyrs, CS 90181, 38042 Grenoble (France)

    2015-01-01T23:59:59.000Z

    A robotic sample changer for solution X-ray scattering experiments optimized for speed and to use the minimum amount of material has been developed. This system is now in routine use at three high-brilliance European synchrotron sites, each capable of several hundred measurements per day. Small-angle X-ray scattering (SAXS) of macromolecules in solution is in increasing demand by an ever more diverse research community, both academic and industrial. To better serve user needs, and to allow automated and high-throughput operation, a sample changer (BioSAXS Sample Changer) that is able to perform unattended measurements of up to several hundred samples per day has been developed. The Sample Changer is able to handle and expose sample volumes of down to 5 µl with a measurement/cleaning cycle of under 1 min. The samples are stored in standard 96-well plates and the data are collected in a vacuum-mounted capillary with automated positioning of the solution in the X-ray beam. Fast and efficient capillary cleaning avoids cross-contamination and ensures reproducibility of the measurements. Independent temperature control for the well storage and for the measurement capillary allows the samples to be kept cool while still collecting data at physiological temperatures. The Sample Changer has been installed at three major third-generation synchrotrons: on the BM29 beamline at the European Synchrotron Radiation Facility (ESRF), the P12 beamline at the PETRA-III synchrotron (EMBL@PETRA-III) and the I22/B21 beamlines at Diamond Light Source, with the latter being the first commercial unit supplied by Bruker ASC.

  5. National School on Neutron and X-ray Scattering Oak Ridge National Laboratory June 12-26, 2010 Oak Ridge, Tennessee

    E-Print Network [OSTI]

    Pennycook, Steve

    National School on Neutron and X-ray Scattering Oak Ridge National Laboratory June 12-26, 2010 Oak:30 Lecture Inelastic Neutron Scattering B. D. Gaulin McMaster University Lecture Magnetic Scattering B. D Break Break Break Break 9:45 - 10:45 Lecture Continued Inelastic Neutron Scattering B. D. Gaulin Mc

  6. Your access to the Oak Ridge National Laboratory (ORNL) is approved beginning Sunday, June 20, 2010, for the second week of the Neutron X-ray Scattering School.

    E-Print Network [OSTI]

    Pennycook, Steve

    , for the second week of the Neutron X-ray Scattering School. Please be certain to bring photo identification access to the Target Facility.) · General User Access Training for Neutron Scattering Users, Neutron Scattering Science User Office Oak Ridge National Laboratory ORNL Neutron Scattering School June

  7. Probing single magnon excitations in Sr?IrO? using O K-edge resonant inelastic x-ray scattering

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Liu, X.; Dean, M. P. M.; Liu, J.; Chiuzbaian, S. G.; Jaouen, N.; Nicolaou, A.; Yin, W. G.; Rayan Serrao, C.; Ramesh, R.; Ding, H.; et al

    2015-05-27T23:59:59.000Z

    Resonant inelastic X-ray scattering (RIXS) at the L-edge of transition metal elements is now commonly used to probe single magnon excitations. Here we show that single magnon excitations can also be measured with RIXS at the K-edge of the surrounding ligand atoms when the center heavy metal elements have strong spin-orbit coupling. This is demonstrated with oxygen K-edge RIXS experiments on the perovskite Sr?IrO?, where low energy peaks from single magnon excitations were observed. This new application of RIXS has excellent potential to be applied to a wide range of magnetic systems based on heavy elements, for which the L-edgemore »RIXS energy resolutions in the hard X-ray region is usually poor.« less

  8. Probing single magnon excitations in Sr?IrO? using O K-edge resonant inelastic x-ray scattering

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Liu, X. [Chinese Academy of Sciences (CAS), Beijing (China). Beijing National Lab. for Condensed Matter Physics (BNLCP-CAS); Brookhaven National Lab. (BNL), Upton, NY (United States); Collaborative Innovation Center of Quantum Matter, Beijing (China); Dean, M. P. M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Liu, J. [Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Chiuzbaian, S. G. [Sorbonne Univ., Paris (France); Synchrotron SOLEIL, Saint-Aubin (France); Jaouen, N. [Synchrotron SOLEIL, Saint-Aubin (France); Nicolaou, A. [Synchrotron SOLEIL, Saint-Aubin (France); Yin, W. G. [Brookhaven National Lab. (BNL), Upton, NY (United States); Rayan Serrao, C. [Univ. of California, Berkeley, CA (United States); Ramesh, R. [Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Ding, H. [Chinese Academy of Sciences (CAS), Beijing (China). Beijing National Lab. for Condensed Matter Physics (BNLCP-CAS); Collaborative Innovation Center of Quantum Matter, Beijing (China); Hill, J. P. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-05-27T23:59:59.000Z

    Resonant inelastic X-ray scattering (RIXS) at the L-edge of transition metal elements is now commonly used to probe single magnon excitations. Here we show that single magnon excitations can also be measured with RIXS at the K-edge of the surrounding ligand atoms when the center heavy metal elements have strong spin-orbit coupling. This is demonstrated with oxygen K-edge RIXS experiments on the perovskite Sr?IrO?, where low energy peaks from single magnon excitations were observed. This new application of RIXS has excellent potential to be applied to a wide range of magnetic systems based on heavy elements, for which the L-edge RIXS energy resolutions in the hard X-ray region is usually poor.

  9. Evidence for the Importance of Resonance Scattering in X-Ray Emission Line Profiles of the O Star Zeta Puppis

    SciTech Connect (OSTI)

    Leutenegger, M.A.; /Columbia U.; Owocki, S.P.; /Bartol Research Inst.; Kahn, S.M.; /KIPAC, Menlo Park; Paerels, F.B.S.; /Columbia U.

    2006-10-10T23:59:59.000Z

    We fit the Doppler profiles of the He-like triplet complexes of O VII and N VI in the X-ray spectrum of the O star {zeta} Pup, using XMM-Newton RGS data collected over {approx} 400 ks of exposure. We find that they cannot be well fit if the resonance and intercombination lines are constrained to have the same profile shape. However, a significantly better fit is achieved with a model incorporating the effects of resonance scattering, which causes the resonance line to become more symmetric than the intercombination line for a given characteristic continuum optical depth {tau}{sub *}. We discuss the plausibility of this hypothesis, as well as its significance for our understanding of Doppler profiles of X-ray emission lines in O stars.

  10. Phase-based x-ray scattering—A possible method to detect cancer cells in a very early stage

    SciTech Connect (OSTI)

    Feye-Treimer, U., E-mail: feye-treimer@helmholtz-berlin.de; Treimer, W. [Department of Mathematics, Physics and Chemistry, University of Applied Sciences, D-13353 Berlin, Germany and Joint Department G-GTOMO, Helmholtz Zentrum fuer Materialien und Energie Berlin, D-14109 Berlin (Germany)] [Department of Mathematics, Physics and Chemistry, University of Applied Sciences, D-13353 Berlin, Germany and Joint Department G-GTOMO, Helmholtz Zentrum fuer Materialien und Energie Berlin, D-14109 Berlin (Germany)

    2014-05-15T23:59:59.000Z

    Purpose: This theoretical work contains a detailed investigation of the potential and sensitivity of phase-based x-ray scattering for cancer detection in biopsies if cancer is in a very early stage of development. Methods: Cancer cells in their early stage of development differ from healthy ones mainly due to their faster growing cell nuclei and the enlargement of their densities. This growth is accompanied by an altered nucleus–plasma relation for the benefit of the cell nuclei, that changes the physical properties especially the index of refraction of the cell and the one of the cell nuclei. Interaction of radiation with matter is known to be highly sensitive to small changes of the index of refraction of matter; therefore a detection of such changes of volume and density of cell nuclei by means of high angular resolved phase-based scattering of x rays might provide a technique to distinguish malignant cells from healthy ones ifthe cell–cell nucleus system is considered as a coherent phase shifting object. Then one can observe from a thin biopsy which represents a monolayer of cells (no multiple scattering) that phase-based x-ray scattering curves from healthy cells differ from those of cancer cells in their early stage of development. Results: Detailed calculations of x-ray scattering patterns from healthy and cancer cell nuclei yield graphs and numbers with which one can distinguish healthy cells from cancer ones, taking into account that both kinds of cells occur in a tissue within a range of size and density. One important result is the role and the influence of the (lateral) coherence width of the radiation on the scattering curves and the sensitivity of phase-based scattering for cancer detection. A major result is that a larger coherence width yields a larger sensitivity for cancer detection. Further import results are calculated limits for critical sizes and densities of cell nuclei in order to attribute the investigated tissue to be healthy or diseased. Conclusions: With this proposed method it should be in principle possible to detect cancer cells in apparently healthy tissues in biopsies and/or in samples of the far border region of abscised or excised tissues. Thus this method could support established methods in diagnostics of cancer-suspicious samples.

  11. Tunable X-ray source

    DOE Patents [OSTI]

    Boyce, James R. (Williamsburg, VA)

    2011-02-08T23:59:59.000Z

    A method for the production of X-ray bunches tunable in both time and energy level by generating multiple photon, X-ray, beams through the use of Thomson scattering. The method of the present invention simultaneously produces two X-ray pulses that are tunable in energy and/or time.

  12. Inelastic x-ray scattering study of supercooled liquid and solid silicon.

    SciTech Connect (OSTI)

    Alatas, A.; Said, A.; Sinn, H.; Alp, E.E.; Kodituwakku, C.N.; Saboungi, M.L.; Price, D.L.; X-Ray Science Division; Western Michigan Univ.; Purdue Univ.; CRMD-CNRS; CRMHT-CNRS

    2006-01-01T23:59:59.000Z

    Momentum-resolved inelastic x-ray scattering (IXS) technique is one of the powerful methods for the study of dynamical properties of a given system even in extreme conditions like high temperature and high pressure. At the same time, experimental studies of physical and structural properties of liquids have multiplied in recent years with the advent of containerless techniques. These methods reduce the possibility of contamination of specimens and remove external nucleation sites. Therefore, by combining the IXS method with the levitation method, the dynamical properties of stable liquids up to 3000 K and supercooled phase of liquids can be studied. Silicon is a basic material in the semiconductor industry and has been the subject of a large amount of experimental and theoretical studies over a long time. In the crystalline phase at ambient conditions, silicon is a diamond-structured semiconductor, but upon melting it undergoes a semiconductor-to-metal transition accompanied by significant changes in the structure and density. The coordination number increases from 4 in the solid to about 6.5 in the liquid, and liquid density is increased by about 10%. The principal purpose of the present study was to determine silicon's elastic modulus from the measurement of averaged sound speed determined from IXS. The experiments were carried out at the Advanced Photon Source (APS) beamline 3-ID with a high-resolution monochromator consisting of two nested channel-cut crystals and four backscattering analyzer setups in the horizontal scattering plane 6 m from the sample. The requirements for very high energy resolution and the basic principles of such instrumentation are discussed elsewhere as referenced. The levitation apparatus was enclosed in a bell jar specially designed for backscattering geometry with a separation of 10 cm between the sample and the detector. Silicon spheres of 2 to 3 mm in diameter were suspended in an argon gas jet and heated with a 270 W CO{sub 2} laser beam. Temperatures were measured during the experiment with a pyrometer whose operating wavelength was 0.65 {micro}m. The temperature gradient on the sample was estimated to be about +/- 20 K. The energy scans were taken for supercooled-liquid and hot-solid silicon at temperature T=1620 K. Sound velocities were determined from the initial slope of the excitation frequencies. Then, the longitudinal moduli for hotsolid and supercooled-liquid silicon were calculated from L = v{sub L}{sup 2}{rho} using measured velocities. In these calculations, density values were taken from Ohsaka et al. as referenced. Results are presented in Table 1. together with room-temperature, hot-solid single-crystal measurements, and stable-liquid values. Room-temperature longitudinal moduli were calculated from the values of the single-crystal elastic constants. They were measured between 300 K and 870 K. Since there was no phase transition up to temperature 1620 K for hot-solid silicon, it is reasonable to extrapolate these data to 1620 K in order to compare to our results for the hot solid. A significant difference (about 20%) is observed between our measurement and the extrapolated single-crystal value of the longitudinal modulus for solid silicon at temperature 1620K. This reduction of the longitudinal modulus may be an indication of the pre-melting. The factor of more than two change in the elastic modulus between supercooled liquid and hot solid at the same temperature can be attributed to the semiconductor-to-metal transition in silicon associated with melting. Also, the longitudinal modulus of the stable liquid is reported in Table 1. About a 10% difference is observed between the modulus of the supercooled and the stable liquid silicon. This can be interpreted as silicon still maintaining metallic properties with a significant increase in the degree of the directional bonding upon supercooling, as found in the x-ray diffraction and ab initio MD studies. All these results are discussed in reference.

  13. Week 2 AGENDA: National School on Neutron and X-ray Scattering page 1 of 5 Oak Ridge National Laboratory [9/30/08

    E-Print Network [OSTI]

    Pennycook, Steve

    Week 2 AGENDA: National School on Neutron and X-ray Scattering page 1 of 5 Oak Ridge National Ridge National Laboratory Dean Myles, Director ORNL Neutron Scattering Science Division 1 GROUPS [A,B,C,D,E,F,G,H,I] Iran Thomas Auditorium Lecture Inelastic Neutron Scattering R. Osborn, ANL ALL

  14. INHOMOGENEITIES IN TYPE Ib/c SUPERNOVAE: AN INVERSE COMPTON SCATTERING ORIGIN OF THE X-RAY EMISSION

    SciTech Connect (OSTI)

    Bjoernsson, C.-I., E-mail: bjornsson@astro.su.se [Department of Astronomy, AlbaNova University Center, Stockholm University, SE-106 91 Stockholm (Sweden)

    2013-05-20T23:59:59.000Z

    Inhomogeneities in a synchrotron source can severely affect the conclusions drawn from observations regarding the source properties. However, their presence is not always easy to establish, since several other effects can give rise to similar observed characteristics. It is argued that the recently observed broadening of the radio spectra and/or light curves in some Type Ib/c supernovae is a direct indication of inhomogeneities. As compared to a homogeneous source, this increases the deduced velocity of the forward shock and the observed correlation between total energy and shock velocity could in part be due to a varying covering factor. The X-ray emission from at least some Type Ib/c supernovae is unlikely to be synchrotron radiation from an electron distribution accelerated in a nonlinear shock. Instead it is shown that the observed correlation during the first few hundred days between the radio, X-ray, and bolometric luminosities indicates that the X-ray emission is inverse Compton scattering of the photospheric photons. Inhomogeneities are consistent with equipartition between electrons and magnetic fields in the optically thin synchrotron emitting regions.

  15. Focus characterization at an X-ray free-electron laser by coherent scattering and speckle analysis

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sikorski, Marcin; Song, Sanghoon; Schropp, Andreas; Seiboth, Frank; Feng, Yiping; Alonso-Mori, Roberto; Chollet, Matthieu; Lemke, Henrik T.; Sokaras, Dimosthenis; Weng, Tsu-Chien; et al

    2015-05-01T23:59:59.000Z

    X-ray focus optimization and characterization based on coherent scattering and quantitative speckle size measurements was demonstrated at the Linac Coherent Light Source. Its performance as a single-pulse free-electron laser beam diagnostic was tested for two typical focusing configurations. The results derived from the speckle size/shape analysis show the effectiveness of this technique in finding the focus' location, size and shape. In addition, its single-pulse compatibility enables users to capture pulse-to-pulse fluctuations in focus properties compared with other techniques that require scanning and averaging.

  16. Bent crystal spectrometer for both frequency and wavenumber resolved x-ray scattering at a seeded free-electron laser

    E-Print Network [OSTI]

    Zastrau, Ulf; Foerster, Eckhart; Galtier, Eric Ch; Gamboa, Eliseo; Glenzer, Siegfried H; Heimann, Philipp; Marschner, Heike; Nagler, Bob; Schropp, Andreas; Wehrhan, Ortrud; Lee, Hae Ja

    2014-01-01T23:59:59.000Z

    We present a cylindrically curved GaAs x-ray spectrometer with energy resolution $\\Delta E/E = 1.1\\cdot 10^{-4}$ and wave-number resolution of $\\Delta k/k = 3\\cdot 10^{-3}$, allowing plasmon scattering at the resolution limits of the Linac Coherent Light Source (LCLS) x-ray free-electron laser. It spans scattering wavenumbers of 3.6 to $5.2/$\\AA\\ in 100 separate bins, with only 0.34\\% wavenumber blurring. The dispersion of 0.418~eV/$13.5\\,\\mu$m agrees with predictions within 1.3\\%. The reflection homogeneity over the entire wavenumber range was measured and used to normalize the amplitude of scattering spectra. The proposed spectrometer is superior to a mosaic HAPG spectrometer when the energy resolution needs to be comparable to the LCLS seeded bandwidth of 1~eV and a significant range of wavenumbers must be covered in one exposure.

  17. Bent crystal spectrometer for both frequency and wavenumber resolved x-ray scattering at a seeded free-electron laser

    SciTech Connect (OSTI)

    Zastrau, Ulf, E-mail: ulf.zastrau@uni-jena.de [Institute of Optics and Quantum Electronics, Friedrich-Schiller University Jena, Max-Wien-Platz 1, 07743 Jena (Germany); Stanford Linear Accelerator Center (SLAC), 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Fletcher, Luke B.; Galtier, Eric Ch.; Gamboa, Eliseo; Glenzer, Siegfried H.; Heimann, Philipp; Nagler, Bob; Schropp, Andreas; Lee, Hae Ja [Stanford Linear Accelerator Center (SLAC), 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Förster, Eckhart [Institute of Optics and Quantum Electronics, Friedrich-Schiller University Jena, Max-Wien-Platz 1, 07743 Jena (Germany); Helmholtz Institute Jena, Fröbelstieg 3, 07743 Jena (Germany); Marschner, Heike; Wehrhan, Ortrud [Institute of Optics and Quantum Electronics, Friedrich-Schiller University Jena, Max-Wien-Platz 1, 07743 Jena (Germany)

    2014-09-15T23:59:59.000Z

    We present a cylindrically curved GaAs x-ray spectrometer with energy resolution ?E/E = 1.1 ×?10{sup ?4} and wave-number resolution of ?k/k = 3 ×?10{sup ?3}, allowing plasmon scattering at the resolution limits of the Linac Coherent Light Source (LCLS) x-ray free-electron laser. It spans scattering wavenumbers of 3.6 to 5.2/Å in 100 separate bins, with only 0.34% wavenumber blurring. The dispersion of 0.418 eV/13.5??m agrees with predictions within 1.3%. The reflection homogeneity over the entire wavenumber range was measured and used to normalize the amplitude of scattering spectra. The proposed spectrometer is superior to a mosaic highly annealed pyrolytic graphite spectrometer when the energy resolution needs to be comparable to the LCLS seeded bandwidth of 1 eV and a significant range of wavenumbers must be covered in one exposure.

  18. Ultra-fast x-ray Thomson scattering measurements of insulator-metal transition in shock-compressed matter

    SciTech Connect (OSTI)

    Kritcher, A; Neumayer, P; Castor, J; Doppner, T; Falcone, R W; Landen, O L; Lee, H J; Lee, R W; Morse, E C; Ng, A; Pollaine, S; Price, D; Glenzer, S H

    2008-05-16T23:59:59.000Z

    Spectrally resolved scattering of ultra-short pulse laser-generated K-{alpha} x rays has been applied to measure the heating and compression of shocked solid-density lithium hydride. Two shocks launched by a nanosecond laser pulse coalesce yielding pressures of 400 gigapascals. The evolution of the intensity of the elastic (Rayleigh) scattering component indicates rapid heating to temperatures of 25,000 K on a 100 ps time scale. At shock coalescence, the scattering spectra show the collective plasmon oscillations indicating the transition to the dense metallic plasma state. The plasmon frequency determines the material compression, which is found to be a factor of three thereby reaching conditions in the laboratory important for studying astrophysics phenomena.

  19. Center for X-Ray Optics, 1992

    SciTech Connect (OSTI)

    Not Available

    1993-08-01T23:59:59.000Z

    This report discusses the following topics: Center for X-Ray Optics; Soft X-Ray Imaging wit Zone Plate Lenses; Biological X-Ray microscopy; Extreme Ultraviolet Lithography for Nanoelectronic Pattern Transfer; Multilayer Reflective Optics; EUV/Soft X-ray Reflectometer; Photoemission Microscopy with Reflective Optics; Spectroscopy with Soft X-Rays; Hard X-Ray Microprobe; Coronary Angiography; and Atomic Scattering Factors.

  20. SU-E-I-76: Matching Primary and Scattered X-Ray Spectra for Use in Calculating the Diagnostic Radiation Index of Protection

    SciTech Connect (OSTI)

    Pasciak, A [University of Tennessee Medical Center, Knoxville, TN (United States); Jones, A [MD Anderson Cancer Center, Houston, TX (United States); Wagner, L [UT Medical School, Houston, TX (United States)

    2014-06-01T23:59:59.000Z

    Purpose: Lightweight lead-free or lead-composite protective garments exploit k-edge interactions to attenuate scattered X-rays. Manufacturers specify the protective value of garments in terms of lead equivalence at a single kVp. This is inadequate, as the protection provided by such garments varies with radiation quality in different use conditions. We present a method for matching scattered X-ray spectra to primary X-ray spectra. The resulting primary spectra can be used to measure penetration through protective garments, and such measurements can be weighted and summed to determine a Diagnostic Radiation Index for Protection (DRIP). Methods: Scattered X-ray spectra from fluoroscopic procedures were modeled using Monte Carlo techniques in MCNP-X 2.7. Data on imaging geometry, operator position, patient size, and primary beam spectra were gathered from clinical fluoroscopy procedures. These data were used to generate scattered X-ray spectra resulting from procedural conditions. Technical factors, including kV and added filtration, that yielded primary X-ray spectra that optimally matched the generated scattered X-ray spectra were identified through numerical optimization using a sequential quadratic programming (SQP) algorithm. Results: The primary spectra generated with shape functions matched the relative flux in each bin of the scattered spectra within 5%, and half and quarter-value layers matched within 0.1%. The DRIP for protective garments can be determined by measuring the penetration through protective garments using the matched primary spectra, then calculating a weighted average according to the expected clinical use of the garment. The matched primary spectra are specified in terms of first and second half-value layers in aluminum and acrylic. Conclusion: Lead equivalence is inadequate for completely specifying the protective value of garments. Measuring penetration through a garment using full scatter conditions is very difficult. The primary spectra determined in this work allow for practical primary penetration measurements to be made with equipment readily available to clinical medical physicists.

  1. In Situ X-Ray Scattering Helps Optimize Printed Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC) EnvironmentalGyroSolé(tm)HydrogenRFP » Important TrinityEnergyIn Situ X-Ray

  2. In Situ X-Ray Scattering Helps Optimize Printed Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC) EnvironmentalGyroSolé(tm)HydrogenRFP » Important TrinityEnergyIn Situ X-RayIn

  3. In Situ X-Ray Scattering Helps Optimize Printed Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC) EnvironmentalGyroSolé(tm)HydrogenRFP » Important TrinityEnergyIn Situ X-RayInIn

  4. A general framework and review of scatter correction methods in x-ray cone-beam computerized tomography. Part 1: Scatter compensation approaches

    SciTech Connect (OSTI)

    Ruehrnschopf, Ernst-Peter; Klingenbeck, Klaus [Siemens AG, Healthcare Sector, Imaging and Therapy Division, Forchheim (Germany)

    2011-07-15T23:59:59.000Z

    Since scattered radiation in cone-beam volume CT implies severe degradation of CT images by quantification errors, artifacts, and noise increase, scatter suppression is one of the main issues related to image quality in CBCT imaging. The aim of this review is to structurize the variety of scatter suppression methods, to analyze the common structure, and to develop a general framework for scatter correction procedures. In general, scatter suppression combines hardware techniques of scatter rejection and software methods of scatter correction. The authors emphasize that scatter correction procedures consist of the main components scatter estimation (by measurement or mathematical modeling) and scatter compensation (deterministic or statistical methods). The framework comprises most scatter correction approaches and its validity also goes beyond transmission CT. Before the advent of cone-beam CT, a lot of papers on scatter correction approaches in x-ray radiography, mammography, emission tomography, and in Megavolt CT had been published. The opportunity to avail from research in those other fields of medical imaging has not yet been sufficiently exploited. Therefore additional references are included when ever it seems pertinent. Scatter estimation and scatter compensation are typically intertwined in iterative procedures. It makes sense to recognize iterative approaches in the light of the concept of self-consistency. The importance of incorporating scatter compensation approaches into a statistical framework for noise minimization has to be underscored. Signal and noise propagation analysis is presented. A main result is the preservation of differential-signal-to-noise-ratio (dSNR) in CT projection data by ideal scatter correction. The objective of scatter compensation methods is the restoration of quantitative accuracy and a balance between low-contrast restoration and noise reduction. In a synopsis section, the different deterministic and statistical methods are discussed with respect to their properties and applications. The current paper is focused on scatter compensation algorithms. The multitude of scatter estimation models will be dealt with in a separate paper.

  5. X-ray scattering studies of structure and dynamics of surfaces and interfaces of polymeric liquids

    E-Print Network [OSTI]

    Jiang, Zhang

    2007-01-01T23:59:59.000Z

    and S. K. Sinha, “Structure and dynamics of thin polymer ?Scattering Studies of Structure and Dynamics of Surfaces andScattering Studies of Structure and Dynamics of Surfaces and

  6. An alternative scheme of angular-dispersion analyzers for high-resolution medium-energy inelastic X-ray scattering

    E-Print Network [OSTI]

    Huang, Xian-Rong

    2011-01-01T23:59:59.000Z

    The development of medium-energy inelastic X-ray scattering (IXS) optics with meV and sub-meV resolution has attracted considerable efforts in recent years. Meanwhile, there are also concerns or debates about the fundamental and feasibility of the involved schemes. Here the central optical component, the back-reflection angular-dispersion monochromator or analyzer, is analyzed. The results show that the multiple-beam diffraction effect together with transmission-induced absorption can noticeably reduce the diffraction efficiency, although it may not be a fatal threat. In order to improve the efficiency, a simple four-bounce analyzer is proposed that completely avoids these two adverse effects. The new scheme is illustrated to be a feasible alternative approach for developing meV- to sub-meV-resolution IXS spectroscopy.

  7. Resonant inelastic x-ray scattering study of charge excitations in superconducting and nonsuperconducting PrFeAsO??y

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Jarrige, I.; Nomura, T.; Ishii, K.; Gretarsson, H.; Kim, Y.-J.; Kim, J.; Upton, M.; Casa, D.; Gog, T.; Ishikado, M.; Fukuda, T.; Yoshida, M.; Hill, J. P.; Liu, X.; Hiraoka, N.; Tsuei, K. D.; Shamoto, S.

    2012-09-01T23:59:59.000Z

    We report the first observation by momentum-resolved resonant inelastic x-ray scattering of charge excitations in an iron-based superconductor and its parent compound, PrFeAsO?.? and PrFeAsO, respectively, with two main results. First, using calculations based on a 16-band dp model, we show that the energy of the lowest-lying excitations, identified as dd interband transitions of dominant xz,yz orbital character, exhibits a dramatic dependence on electron correlation. This enables us to estimate the Coulomb repulsion U and Hund's coupling J, and to highlight the role played by J in these peculiar orbital-dependent electron correlation effects. Second, we show that short-range antiferromagnetic correlations, which are a prerequisite to the occurrence of these excitations at the ? point, are still present in the superconducting state.

  8. The phonon density of states of (alpha) and (delta)-Plutonium by inelastic x-ray scattering

    SciTech Connect (OSTI)

    Manley, M E; Said, A; Fluss, M J; Wall, M; Lashley, J C; Alatas, A; Moore, K T

    2008-10-08T23:59:59.000Z

    Inelastic x-ray scattering measurements of the phonon density of states (DOS) were performed on polycrystalline samples of pure {alpha}-Pu and {delta}-Pu{sub 0.98}Ga{sub 0.02} at room temperature. The heat capacity of {alpha}-Pu is well reproduced by contributions calculated from the measured phonon DOS plus conventional thermal expansion and electronic contributions, showing that {alpha}-Pu is a 'well-behaved' metal in this regard. A comparison of the phonon DOS of the two phases at room temperature surprised us in that the vibrational entropy difference between them is only a quarter of the total entropy difference expected from known thermodynamic measurements. The missing entropy is too large to be accounted for by conventional electronic entropy and evidence from the literature rules out a contribution from spin fluctuations. Possible alternative sources for the missing entropy are discussed.

  9. SMALL-ANGUS X-RAY SCATTERING SYSTEM WITH LINEAR POSITION-SENSITIVE DETECTOR

    E-Print Network [OSTI]

    Forouhi, A.R.

    2010-01-01T23:59:59.000Z

    under Contract No. W-7405-ENG-48 (BS, V P - M ) . Referencesof Energy under Contract W-7405-ENG-48 SMALL-ANGLE X-RAYSW-7405-ENG-48. — DHCIMKR _ DKTMBUTItW OF TUB CDCUMMT IE W|

  10. Angle-resolved environmental X-ray photoelectron spectroscopy: A new laboratory setup for photoemission studies at pressures up to 0.4 Torr

    SciTech Connect (OSTI)

    Mangolini, F.; Wabiszewski, G. E.; Egberts, P. [Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania, 220 S. 33rd Street, Philadelphia, Pennsylvania 19104 (United States); Ahlund, J.; Backlund, K.; Karlsson, P. G. [VG Scienta AB, Box 15120, SE-750 15 Uppsala (Sweden); Adiga, V. P.; Streller, F. [Department of Materials Science and Engineering, University of Pennsylvania, 3231 Walnut Street, Philadelphia, Pennsylvania 19104 (United States); Wannberg, B. [VG Scienta AB, Box 15120, SE-750 15 Uppsala (Sweden); BW Particle Optics AB, P.O. Box 55, SE-822 22 Alfta (Sweden); Carpick, R. W. [Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania, 220 S. 33rd Street, Philadelphia, Pennsylvania 19104 (United States); Department of Materials Science and Engineering, University of Pennsylvania, 3231 Walnut Street, Philadelphia, Pennsylvania 19104 (United States)

    2012-09-15T23:59:59.000Z

    The paper presents the development and demonstrates the capabilities of a new laboratory-based environmental X-ray photoelectron spectroscopy system incorporating an electrostatic lens and able to acquire spectra up to 0.4 Torr. The incorporation of a two-dimensional detector provides imaging capabilities and allows the acquisition of angle-resolved data in parallel mode over an angular range of 14 Degree-Sign without tilting the sample. The sensitivity and energy resolution of the spectrometer have been investigated by analyzing a standard Ag foil both under high vacuum (10{sup -8} Torr) conditions and at elevated pressures of N{sub 2} (0.4 Torr). The possibility of acquiring angle-resolved data at different pressures has been demonstrated by analyzing a silicon/silicon dioxide (Si/SiO{sub 2}) sample. The collected angle-resolved spectra could be effectively used for the determination of the thickness of the native silicon oxide layer.

  11. X-ray Raman scattering with Bragg diffraction in a La-based superlattice

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    at the BESSY synchrotron facility. The spectral bandwidth of the quasi- monochromatic radiation delivered of attention, in connection with the development of third generation synchrotrons [9-11]. Inelastic scattering

  12. angle light scattering: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biological tissues tend Kim, Arnold D. 11 Static light scattering and small-angle neutron scattering study on aggregated recombinant gelatin in aqueous solution University...

  13. A small X-ray corona of the narrow-angle tail radio galaxy NGC 1265 soaring through the Perseus cluster

    E-Print Network [OSTI]

    M. Sun; D. Jerius; C. Jones

    2005-07-14T23:59:59.000Z

    A deep Chandra observation of NGC 1265 (3C 83.1B), the prototype for the narrow-angled-tailed (NAT) radio galaxy, reveals a small cool X-ray thermal corona (~ 0.6 keV) embedded in the hot ICM of the Perseus cluster (~ 6.7 keV). The corona is asymmetric with a sharp edge (~ 2.2'', or 0.8 kpc from the nucleus) to the south and an extension to the north (at least ~ 8'' from the nucleus), which is interpreted as the action of ram pressure while solely the static ICM confinement is unable to explain. We estimate that the corona is moving with a velocity of ~ 2.4 - 4.2 times the local sound speed to the south. The presence of the sharp edge for this small corona indicates that the transport processes are largely suppressed by the magnetic field there. The magnetic field around the corona also suppresses heat conduction by at least a factor of ~ 60 across the corona boundary. We conclude that it is unrealistic to study the interaction of the small X-ray coronae with the hot ICM without the consideration of the roles that magnetic field plays, a factor not included in current simulations. An absorbed (N_H=1.5-3x10^22 cm^-2) nucleus is also detected, which is not usual for FR I radio galaxies. Weak X-ray emission from three inner radio knots in the jets is also detected. Indentations at the east and west of the corona indicate interaction between the jets and the X-ray corona. Narrow jets carry great amounts of energy out of the central AGN and release the energy outside the corona, preserving the tiny and vulnerable corona. This case reveals that the inner kpc core of the corona of massive galaxies can survive both high-speed stripping and powerful AGN feedback. Thus, the cooling of the X-ray coronae potentially provides fuel to the central SMBH in rich environments where the amount of the galactic cold gas is at a minimum.

  14. A short working distance multiple crystal x-ray spectrometer

    SciTech Connect (OSTI)

    Dickinson, B.; Seidler, G. T.; Webb, Z. W.; Bradley, J. A.; Nagle, K. P. [Department of Physics, University of Washington, Seattle, Washington 98195 (United States); Heald, S. M. [Advanced Photon Source, Argonne National Laboratories, Argonne, Illinois 60439 (United States); Gordon, R. A. [Department of Physics, Simon Fraser University, Burnaby, British Columbia V5A 1S6 (Canada); Chou, I. M. [U.S. Geological Survey, Reston, Virginia 20192 (United States)

    2008-12-15T23:59:59.000Z

    For x-ray spot sizes of a few tens of microns or smaller, a millimeter-sized flat analyzer crystal placed {approx}1 cm from the sample will exhibit high energy resolution while subtending a collection solid angle comparable to that of a typical spherically bent crystal analyzer (SBCA) at much larger working distances. Based on this observation and a nonfocusing geometry for the analyzer optic, we have constructed and tested a short working distance (SWD) multicrystal x-ray spectrometer. This prototype instrument has a maximum effective collection solid angle of 0.14 sr, comparable to that of 17 SBCA at 1 m working distance. We find good agreement with prior work for measurements of the Mn K{beta} x-ray emission and resonant inelastic x-ray scattering for MnO, and also for measurements of the x-ray absorption near-edge structure for Dy metal using L{alpha}{sub 2} partial-fluorescence yield detection. We discuss future applications at third- and fourth-generation light sources. For concentrated samples, the extremely large collection angle of SWD spectrometers will permit collection of high-resolution x-ray emission spectra with a single pulse of the Linac Coherent Light Source. The range of applications of SWD spectrometers and traditional multi-SBCA instruments has some overlap, but also is significantly complementary.

  15. Transient B12-Dependent Methyltransferase Complexes Revealed by Small-Angle X-ray Scattering

    E-Print Network [OSTI]

    Ando, Nozomi

    In the Wood?Ljungdahl carbon fixation pathway, protein?protein interactions between methyltransferase (MeTr) and corrinoid iron?sulfur protein (CFeSP) are required for the transfer of a methyl group. While crystal structures ...

  16. angle x-ray scattering: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Sources by Dust in Intervening Galaxies Astrophysics (arXiv) Summary: Gamma-ray bursts are now known to be a cosmological population of objects, which are often...

  17. AN EFFICIENT PARALLEL GPU EVALUATION OF SMALL ANGLE X-RAY SCATTERING PROFILES

    E-Print Network [OSTI]

    Hamelryck, Thomas

    the scat- tering curve from a condensation of a gas of "dummy beads" to an experi environment. Re- cently, with the advent of automated high-throughput SAXS analysis of biomolecules (Toft et

  18. Time-Resolved Small-Angle X-ray Scattering Studies Revealed Three Kinetic

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin Transition in2, 2003 (Next ReleaseThomasTheoriesClean1,6,TimeStages

  19. Investigating Silicon-Based Photoresists with Coherent Anti-Stokes Raman Scattering and X-ray Micro-spectroscopy

    E-Print Network [OSTI]

    Caster, Allison G.

    2010-01-01T23:59:59.000Z

    LIGHT (X- RAYS , EUV, ULTRAFAST PULSES ), OR HEAT . T HEthe “on” time of an ultrafast pulse is referred to as thepeak-power of the ultrafast pulses, purely electronic four-

  20. Compton backscattered and primary X-rays from solar flares: angle dependent Green's function correction for photospheric albedo

    E-Print Network [OSTI]

    Eduard P. Kontar; Alec L. MacKinnon; Richard A. Schwartz; John C. Brown

    2005-10-06T23:59:59.000Z

    The observed hard X-ray (HXR) flux spectrum $I(\\epsilon)$ from solar flares is a combination of primary bremsstrahlung photons $I_P(\\epsilon)$ with a spectrally modified component from photospheric Compton backscatter of downward primary emission. The latter can be significant, distorting or hiding the true features of the primary spectrum which are key diagnostics for acceleration and propagation of high energy electrons and of their energy budget. For the first time in solar physics, we use a Green's function approach to the backscatter spectral deconvolution problem, constructing a Green's matrix including photoelectric absorption. This approach allows spectrum-independent extraction of the primary spectrum for several HXR flares observed by the {\\it Ramaty High Energy Solar Spectroscopic Imager} (RHESSI). We show that the observed and primary spectra differ very substantially for flares with hard spectra close to the disk centre. We show in particular that the energy dependent photon spectral index $\\gamma (\\epsilon)=-d \\log I/d \\log \\epsilon$ is very different for $I_P(\\epsilon)$ and for $I(\\epsilon)$ and that inferred mean source electron spectra ${\\bar F}(E)$ differ greatly. Even for a forward fitting of a parametric ${\\bar F}(E)$ to the data, a clear low-energy cutoff required to fit $I(\\epsilon)$ essentially disappears when the fit is to $I_P(\\epsilon)$ - i.e. when albedo correction is included. The self-consistent correction for backscattered photons is thus shown to be crucial in determining the energy spectra of flare accelerated electrons, and hence their total number and energy.

  1. Hydrostatic low-range pressure applications of the Paris-Edinburgh cell utilising polymer gaskets for diffuse x-ray scattering measurements.

    SciTech Connect (OSTI)

    Chapman, K. W.; Chupas, P. J.; Kurtz, C.; Locke, D.; Parise, J. B.; Hriljac, J. A.; Stony Brook Univ.; Univ. of Birmingham

    2007-01-01T23:59:59.000Z

    The use of a polymeric Torlon (polyamide-imide) gasket material in a Paris-Edinburgh pressure cell for in situ high-pressure X-ray scattering measurements is demonstrated. The relatively low bulk modulus of the gasket allows for fine control of the sample pressure over the range 0.01-0.42 GPa. The quality of the data obtained in this way is suitable for Bragg and pair distribution function analysis.

  2. Fractal Analysis of Flame-Synthesized Nanostructured Silica and Titania Powders Using Small-Angle X-ray

    E-Print Network [OSTI]

    Beaucage, Gregory

    Fractal Analysis of Flame-Synthesized Nanostructured Silica and Titania Powders Using Small-Angle X these powders display mass-fractal morphologies, which are composed of ramified aggregates of nanoscale primary particles. Primary particle size, aggregate size, fractal dimension, and specific surface area are obtained

  3. SU-C-18C-02: Specifcation of X-Ray Projection Angles Which Are Aligned with the Aortic Valve Plane From a Planar Image of a Valvuloplasty Balloon Inflated Across the Aortic Valve

    SciTech Connect (OSTI)

    Fetterly, K; Mathew, V [Mayo Clinic, Rochester, MN (United States)

    2014-06-01T23:59:59.000Z

    Purpose: Transcatheter aortic valve replacement (TAVR) procedures provide a method to implant a prosthetic aortic valve via a minimallyinvasive, catheter-based procedure. TAVR procedures require use of interventional fluoroscopy c-arm projection angles which are aligned with the aortic valve plane to minimize prosthetic valve positioning error due to x-ray imaging parallax. The purpose of this work is to calculate the continuous range of interventional fluoroscopy c-arm projection angles which are aligned with the aortic valve plane from a single planar image of a valvuloplasty balloon inflated across the aortic valve. Methods: Computational methods to measure the 3D angular orientation of the aortic valve were developed. Required inputs include a planar x-ray image of a known valvuloplasty balloon inflated across the aortic valve and specifications of x-ray imaging geometry from the DICOM header of the image. A-priori knowledge of the species-specific typical range of aortic orientation is required to specify the sign of the angle of the long axis of the balloon with respect to the x-ray beam. The methods were validated ex-vivo and in a live pig. Results: Ex-vivo experiments demonstrated that the angular orientation of a stationary inflated valvuloplasty balloon can be measured with precision less than 1 degree. In-vivo pig experiments demonstrated that cardiac motion contributed to measurement variability, with precision less than 3 degrees. Error in specification of x-ray geometry directly influences measurement accuracy. Conclusion: This work demonstrates that the 3D angular orientation of the aortic valve can be calculated precisely from a planar image of a valvuloplasty balloon inflated across the aortic valve and known x-ray geometry. This method could be used to determine appropriate c-arm angular projections during TAVR procedures to minimize x-ray imaging parallax and thereby minimize prosthetic valve positioning errors.

  4. Structural and magnetic properties of transition metal substituted BaFe{sub 2}As{sub 2} compounds studied by x-ray and neutron scattering

    SciTech Connect (OSTI)

    Kim, Min Gyu [Ames Laboratory

    2012-08-28T23:59:59.000Z

    The purpose of my dissertation is to understand the structural and magnetic properties of the newly discovered FeAs-based superconductors and the interconnection between superconductivity, antiferromagnetism, and structure. X-ray and neutron scattering techniques are powerful tools to directly observe the structure and magnetism in this system. I used both xray and neutron scattering techniques on di#11;erent transition substituted BaFe2As2 compounds in order to investigate the substitution dependence of structural and magnetic transitions and try to understand the connections between them.

  5. Combining THz laser excitation with resonant soft X-ray scattering at the Linac Coherent Light Source

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Turner, Joshua J.; Dakovski, Georgi L.; Hoffmann, Matthias C.; Hwang, Harold Y.; Zarem, Alex; Schlotter, William F.; Moeller, Stefan; Minitti, Michael P.; Staub, Urs; Johnson, Steven; et al

    2015-05-01T23:59:59.000Z

    This paper describes the development of new instrumentation at the Linac Coherent Light Source for conducting THz excitation experiments in an ultra high vacuum environment probed by soft X-ray diffraction. This consists of a cantilevered, fully motorized mirror system which can provide 600 kV cm?¹ electric field strengths across the sample and an X-ray detector that can span the full Ewald sphere with in-vacuum motion. The scientific applications motivated by this development, the details of the instrument, and spectra demonstrating the field strengths achieved using this newly developed system are discussed.

  6. angle scattering studies: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    report gives selected examples illustrating the use of specific techni- cal 2 Small-Angle Neutron Scattering Studies of Charged Carboxyl-Terminated Dendrimers in Solutions...

  7. Reflection soft X-ray microscope and method

    DOE Patents [OSTI]

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

    1993-01-05T23:59:59.000Z

    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.

  8. A Survey of Students from the National School on Neutron and X-ray Scattering: Communication Habits and Preferences

    SciTech Connect (OSTI)

    Bryant, Rebecca [Bryant Research, LLC

    2010-12-01T23:59:59.000Z

    Oak Ridge National Laboratory (ORNL) offers the scientific community unique access to two types of world-class neutron sources at a single site - the Spallation Neutron Source (SNS) and the High Flux Isotope Reactor (HFIR). The 85-MW HFIR provides one of the highest steady-state neutron fluxes of any research reactor in the world. And the SNS is one of the world's most intense pulse neutron beams. Management of these resources is the responsibility of the Neutron Sciences Directorate (NScD). NScD started conducting the National School on Neutron and X-ray Scattering (NXS) in conjunction with the Advanced Photon Source (APS) at Argonne National Laboratory in 2007. This survey was conducted to determine the most effective ways to reach students with information about what SNS and HFIR offer the scientific community, including content and communication vehicles. The emphasis is on gaining insights into compelling messages and the most effective channels, e.g., Web sites and social media, for communicating with students about neutron science The survey was conducted in two phases using a classic qualitative investigation to confirm language and content followed by a survey designed to quantify issues, assumptions, and working hypotheses. Phase I consisted of a focus group in late June 2010 with students attending NXS. The primary intent of the group was to inform development of an online survey. Phase two consisted of an online survey that was developed and pre-tested in July 2010 and launched on August 9, 2010 and remained in the field until September 9, 2010. The survey achieved an overall response rate of 48% for a total of 157 completions. The objective of this study is to determine the most effective ways to reach students with information about what SNS and HFIR offer the scientific community, including content and communication vehicles. The emphasis is on gaining insights into compelling messages and the most effective channels, e.g., Web sites, social media, for communicating with students about neutron science.

  9. Sub-100-ps structural dynamics of horse heart myoglobin probed by time-resolved X-ray solution scattering

    E-Print Network [OSTI]

    Ihee, Hyotcherl

    Sub-100-ps structural dynamics of horse heart myoglobin probed by time-resolved X-ray solution-slicing Structural dynamics Myoglobin a b s t r a c t Here we report sub-100-ps structural dynamics of horse heart rearrangement [27]. In this work, we extend the time-slicing scheme to a protein, horse heart myoglobin (Mb

  10. Probing bismuth ferrite nanoparticles by hard x-ray photoemission: Anomalous occurrence of metallic bismuth

    SciTech Connect (OSTI)

    Chaturvedi, Smita; Rajendra, Ranguwar; Ballav, Nirmalya; Kulkarni, Sulabha, E-mail: s.kulkarni@iiserpune.ac.in [Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pune 411008 (India); Sarkar, Indranil [DESY Photon Science, Deutsches Elektronen-Synchrotron, 22607 Hamburg (Germany); Shirolkar, Mandar M. [Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026 (China); Jeng, U-Ser; Yeh, Yi-Qi [National Synchrotron Radiation Research Center, 101, Hsin-Ann Road, Science Park, Hsinchu 3007-6, Taiwan (China)

    2014-09-08T23:59:59.000Z

    We have investigated bismuth ferrite nanoparticles (?75?nm and ?155?nm) synthesized by a chemical method, using soft X-ray (1253.6?eV) and hard X-ray (3500, 5500, and 7500?eV) photoelectron spectroscopy. This provided an evidence for the variation of chemical state of bismuth in crystalline, phase pure nanoparticles. X-ray photoelectron spectroscopy analysis using Mg K? (1253.6?eV) source showed that iron and bismuth were present in both Fe{sup 3+} and Bi{sup 3+} valence states as expected for bismuth ferrite. However, hard X-ray photoelectron spectroscopy analysis of the bismuth ferrite nanoparticles using variable photon energies unexpectedly showed the presence of Bi{sup 0} valence state below the surface region, indicating that bismuth ferrite nanoparticles are chemically inhomogeneous in the radial direction. Consistently, small-angle X-ray scattering reveals a core-shell structure for these radial inhomogeneous nanoparticles.

  11. A multi-crystal wavelength dispersive x-ray spectrometer

    SciTech Connect (OSTI)

    Alonso-Mori, Roberto; Montanez, Paul; Delor, James; Bergmann, Uwe [LCLS, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Kern, Jan [LCLS, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720-8099 (United States); Sokaras, Dimosthenis; Weng, Tsu-Chien; Nordlund, Dennis [SSRL, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Tran, Rosalie; Yachandra, Vittal K.; Yano, Junko [Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720-8099 (United States)

    2012-07-15T23:59:59.000Z

    A multi-crystal wavelength dispersive hard x-ray spectrometer with high-energy resolution and large solid angle collection is described. The instrument is specifically designed for time-resolved applications of x-ray emission spectroscopy (XES) and x-ray Raman scattering (XRS) at X-ray Free Electron Lasers (XFEL) and synchrotron radiation facilities. It also simplifies resonant inelastic x-ray scattering (RIXS) studies of the whole 2d RIXS plane. The spectrometer is based on the Von Hamos geometry. This dispersive setup enables an XES or XRS spectrum to be measured in a single-shot mode, overcoming the scanning needs of the Rowland circle spectrometers. In conjunction with the XFEL temporal profile and high-flux, it is a powerful tool for studying the dynamics of time-dependent systems. Photo-induced processes and fast catalytic reaction kinetics, ranging from femtoseconds to milliseconds, will be resolvable in a wide array of systems circumventing radiation damage.

  12. Propagation of a strong x-ray pulse: Pulse compression, stimulated Raman scattering, amplified spontaneous emission, lasing without inversion, and four-wave mixing

    SciTech Connect (OSTI)

    Sun Yuping; Wang Chuankui [College of Physics and Electronics, Shandong Normal University, 250014 Jinan (China); Department of Theoretical Chemistry, School of Biotechnology, Royal Institute of Technology, S-10691 Stockholm (Sweden); Liu Jicai; Gel'mukhanov, Faris [Department of Theoretical Chemistry, School of Biotechnology, Royal Institute of Technology, S-10691 Stockholm (Sweden)

    2010-01-15T23:59:59.000Z

    We study the compression of strong x-ray pulses from x-ray free-electron lasers (XFELs) propagating through the resonant medium of atomic argon. The simulations are based on the three-level model with the frequency of the incident x-ray pulse tuned in the 2p{sub 3/2}-4s resonance. The pulse propagation is accompanied by the self-seeded stimulated resonant Raman scattering (SRRS). The SRRS starts from two channels of amplified spontaneous emission (ASE), 4s-2p{sub 3/2} and 3s-2p{sub 3/2}, which form the extensive ringing pattern and widen the power spectrum. The produced seed field triggers the Stokes ASE channel 3s-2p{sub 3/2}. The population inversion is quenched for longer propagation distances where the ASE is followed by the lasing without inversion (LWI), which amplifies the Stokes component. Both ASE and LWI reshape the input pulse: The compressed front part of the pulse (up to 100 as) is followed by the long tail of the ringing and beating between the pump and Stokes frequencies. The pump pulse also generates weaker Stokes and anti-Stokes fields caused by four-wave mixing. These four spectral bands have fine structures caused by the dynamical Stark effect. A slowdown of the XFEL pulse up to 78% of the speed of light in vacuum is found because of a large nonlinear refractive index.

  13. Separable-spherical-wave approximation: Application to x-ray-absorption fine-structure multiple scattering in ReO sub 3

    SciTech Connect (OSTI)

    Houser, B. (Department of Physics, MS 68, Eastern Washington University, Cheney, Washington 99004 (United States)); Ingalls, R.; Rehr, J.J. (Department of Physics, FM-15, University of Washington, Seattle, Washington 98195 (United States))

    1992-04-01T23:59:59.000Z

    Rehr and Albers have shown that the exact x-ray-absorption fine-structure (XAFS) propagator may be expanded in a separable matrix form, and that the lowest-order term in the expansion yields XAFS formulas that contain spherical-wave corrections, yet retain the simplicity of the plane-wave approximation. This separable-spherical-wave approximation was used to model the multiple-scattering contributions to the XAFS spectrum of rhenium trioxide. We report a modest improvement over the plane-wave approximation.

  14. High-energy magnetic excitations in overdoped La 2 - x Sr x CuO 4 studied by neutron and resonant inelastic x-ray scattering

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wakimoto, S.; Ishii, K.; Kimura, H.; Fujita, M.; Dellea, G.; Kummer, K.; Braicovich, L.; Ghiringhelli, G.; Debeer-Schmitt, L. M.; Granroth, G. E.

    2015-05-01T23:59:59.000Z

    We have performed neutron inelastic scattering and resonant inelastic x-ray scattering (RIXS) at the Cu-L? edge to study high-energy magnetic excitations at energy transfers of more than 100 meV for overdoped La2-xSrxCuO? with x=0.25 (Tc=15 K) and x=0.30 (nonsuperconducting) using identical single-crystal samples for the two techniques. From constant-energy slices of neutron-scattering cross sections, we have identified magnetic excitations up to ~250 meV for x=0.25. Although the width in the momentum direction is large, the peak positions along the (?,?) direction agree with the dispersion relation of the spin wave in the nondoped La?CuO? (LCO), which is consistent with the previous RIXS results of cuprate superconductors. Using RIXS at the Cu-L? edge, we have measured the dispersion relations of the so-called paramagnon mode along both (?,?) and (?,0) directions. Although in both directions the neutron and RIXS data connect with each other and the paramagnon along (?,0) agrees well with the LCO spin-wave dispersion, the paramagnon in the (?,?) direction probed by RIXS appears to be less dispersive and the excitation energy is lower than the spin wave of LCO near (?/2,?/2). Thus, our results indicate consistency between neutron inelastic scattering and RIXS, and elucidate the entire magnetic excitation in the (?,?) direction by the complementary use of two probes. The polarization dependence of the RIXS profiles indicates that appreciable charge excitations exist in the same energy range of magnetic excitations, reflecting the itinerant character of the overdoped sample. A possible anisotropy in the charge excitation intensity might explain the apparent differences in the paramagnon dispersion in the (?,?) direction as detected by the x-ray scattering.

  15. High-energy magnetic excitations in overdoped La 2 - x Sr x CuO 4 studied by neutron and resonant inelastic x-ray scattering

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wakimoto, S.; Ishii, K.; Kimura, H.; Fujita, M.; Dellea, G.; Kummer, K.; Braicovich, L.; Ghiringhelli, G.; Debeer-Schmitt, L. M.; Granroth, G. E.

    2015-05-01T23:59:59.000Z

    We have performed neutron inelastic scattering and resonant inelastic x-ray scattering (RIXS) at the Cu-L? edge to study high-energy magnetic excitations at energy transfers of more than 100 meV for overdoped La2-xSrxCuO? with x=0.25 (Tc=15 K) and x=0.30 (nonsuperconducting) using identical single-crystal samples for the two techniques. From constant-energy slices of neutron-scattering cross sections, we have identified magnetic excitations up to ~250 meV for x=0.25. Although the width in the momentum direction is large, the peak positions along the (?,?) direction agree with the dispersion relation of the spin wave in the nondoped La?CuO? (LCO), which is consistent with themore »previous RIXS results of cuprate superconductors. Using RIXS at the Cu-L? edge, we have measured the dispersion relations of the so-called paramagnon mode along both (?,?) and (?,0) directions. Although in both directions the neutron and RIXS data connect with each other and the paramagnon along (?,0) agrees well with the LCO spin-wave dispersion, the paramagnon in the (?,?) direction probed by RIXS appears to be less dispersive and the excitation energy is lower than the spin wave of LCO near (?/2,?/2). Thus, our results indicate consistency between neutron inelastic scattering and RIXS, and elucidate the entire magnetic excitation in the (?,?) direction by the complementary use of two probes. The polarization dependence of the RIXS profiles indicates that appreciable charge excitations exist in the same energy range of magnetic excitations, reflecting the itinerant character of the overdoped sample. A possible anisotropy in the charge excitation intensity might explain the apparent differences in the paramagnon dispersion in the (?,?) direction as detected by the x-ray scattering.« less

  16. X-ray microscopy using grazing-incidence reflections optics

    SciTech Connect (OSTI)

    Price, R.H.

    1983-06-30T23:59:59.000Z

    The role of Kirkpatrick-Baez microscopes as the workhorse of the x-ray imaging devices is discussed. This role is being extended with the development of a 22X magnification Kirkpatrick-Baez x-ray microscope with multilayer x-ray mirrors. These mirrors can operate at large angles, high x-ray energies, and have a narrow, well defined x-ray energy bandpass. This will make them useful for numerous experiments. However, where a large solid angle is needed, the Woelter microscope will still be necessary and the technology needed to build them will be useful for many other types of x-ray optics.

  17. X-ray microscopy using grazing-incidence reflection optics

    SciTech Connect (OSTI)

    Price, R.H.

    1981-08-06T23:59:59.000Z

    The Kirkpatrick-Baez microscopes are described along with their role as the workhorse of the x-ray imaging devices. This role is being extended with the development of a 22X magnification Kirkpatrick-Baez x-ray microscope with multilayer x-ray mirrors. These mirrors can operate at large angles, high x-ray energies, and have a narrow, well defined x-ray energy bandpass. This will make them useful for numerous experiments. However, where a large solid angle is needed, the Woelter microscope will still be necessary and the technology needed to build them will be useful for many other types of x-ray optics.

  18. Toward a Taxonomy of the Denatured State: Small Angle Scattering Studies of Unfolded Proteins

    SciTech Connect (OSTI)

    Millett, I.S.; Doniach, S.; Plaxco, K.W. (Stanford); (UCSB)

    2005-02-15T23:59:59.000Z

    Despite the critical role the unfolded state plays in defining protein folding kinetics and thermodynamics (Berg et al., 2002; Dunker, 2002; Shortle, 2002; Wright and Dyson, 2002), our understanding of its detailed structure remains rather rudimentary; the heterogeneity of the unfolded ensemble renders difficult or impossible its study by traditional, atomic-level structural methods. Consequently, recent years have seen a significant expansion of small-angle X-ray and neutron scattering (SAXS and SANS, respectively) techniques that provide direct, albeit rotationally and time-averaged, measures of the geometric properties of the unfolded ensemble. These studies have reached a critical mass, allowing us for the first time to define general observations regarding the nature of the geometry - and possibly the chemistry and physics - of unfolded proteins.

  19. SASfit: A comprehensive tool for small-angle scattering data analysis

    E-Print Network [OSTI]

    Breßler, Ingo; Thünemann, Andreas F

    2015-01-01T23:59:59.000Z

    Small-angle X-ray and neutron scattering experiments are used in many fields of the life sciences and condensed matter research to obtain answers to questions about the shape and size of nano-sized structures, typically in the range of 1 to 100 nm. It provides good statistics for large numbers of structural units for short measurement times. With the ever-increasing quantity and quality of data acquisition, the value of appropriate tools that are able to extract valuable information is steadily increasing. SASfit has been one of the mature programs for small-angle scattering data analysis available for many years. We describe the basic data processing and analysis work-flow along with recent developments in the SASfit program package (version 0.94.6). They include (i) advanced algorithms for reduction of oversampled data sets (ii) improved confidence assessment in the optimized model parameters and (iii) a flexible plug-in system for custom user-provided models. A scattering function of a mass fractal model o...

  20. angle neutron scattering: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    neutron scattering First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 SANS -Small Angle Neutron Scattering...

  1. Vacancy-induced nanoscale phase separation in KxFe2–ySe? single crystals evidenced by Raman scattering and powder x-ray diffraction

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Lazarevi?, N.; Abeykoon, M.; Stephens, P. W.; Lei, Hechang; Bozin, E. S.; Petrovic, C.; Popovi?, Z. V.

    2012-08-01T23:59:59.000Z

    Polarized Raman scattering spectra of KxFe2–ySe? were analyzed in terms of peculiarities of both I4/m and I4/mmm space group symmetries. The presence of the Raman active modes from both space group symmetries (16 Raman-active modes of the I4/m phase and two Raman-active modes of the I4/mmm phase) confirmed the existence of two crystallographic domains with different space group symmetry in a KxFe2–ySe? sample. High-resolution synchrotron powder x-ray diffraction structural refinement of the same sample confirmed the two-phase description, and determined the atomic positions and occupancies for both domains.

  2. Combined x-ray scattering, radiography, and velocity interferometry/streaked optical pyrometry measurements of warm dense carbon using a novel technique of shock-and-release

    SciTech Connect (OSTI)

    Falk, K.; Collins, L. A.; Kagan, G.; Kress, J. D.; Montgomery, D. S.; Srinivasan, B. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Gamboa, E. J. [University of Michigan, Ann Arbor, Michigan 48109 (United States) [University of Michigan, Ann Arbor, Michigan 48109 (United States); SLAC National Accelerator Laboratory, 2575 Sand Hill Road, MS 72, Menlo Park, California 94025 (United States); Tzeferacos, P. [Flash Center for Computational Science, University of Chicago, Chicago, Illinois 60637 (United States)] [Flash Center for Computational Science, University of Chicago, Chicago, Illinois 60637 (United States); Benage, J. F. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States) [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)

    2014-05-15T23:59:59.000Z

    This work focused on a new application of the shock-and-release technique for equation of state (EOS) measurements. Warm dense matter states at near normal solid density and at temperatures close to 10?eV in diamond and graphite samples were created using a deep release from a laser-driven shock at the OMEGA laser facility. Independent temperature, density, and pressure measurements that do not depend on any theoretical models or simulations were obtained using imaging x-ray Thomson scattering, radiography, velocity interferometry, and streaked optical pyrometry. The experimental results were reproduced by the 2-D FLASH radiation hydrodynamics simulations finding a good agreement. The final EOS measurement was then compared with widely used SESAME EOS models as well as quantum molecular dynamics simulation results for carbon, which were very consistent with the experimental data.

  3. High-resolution ab initio three-dimensional x-ray diffraction microscopy

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Chapman, Henry N.; Barty, Anton; Marchesini, Stefano; Noy, Aleksandr; Hau-Riege, Stefan P.; Cui, Congwu; Howells, Malcolm R.; Rosen, Rachel; He, Haifeng; Spence, John C.; et al

    2006-01-01T23:59:59.000Z

    Coherent x-ray diffraction microscopy is a method of imaging nonperiodic isolated objects at resolutions limited, in principle, by only the wavelength and largest scattering angles recorded. We demonstrate x-ray diffraction imaging with high resolution in all three dimensions, as determined by a quantitative analysis of the reconstructed volume images. These images are retrieved from the three-dimensional diffraction data using no a priori knowledge about the shape or composition of the object, which has never before been demonstrated on a nonperiodic object. We also construct two-dimensional images of thick objects with greatly increased depth of focus (without loss of transverse spatialmore »resolution). These methods can be used to image biological and materials science samples at high resolution with x-ray undulator radiation and establishes the techniques to be used in atomic-resolution ultrafast imaging at x-ray free-electron laser sources.« less

  4. High-resolution ab initio Three-dimensional X-ray Diffraction Microscopy

    SciTech Connect (OSTI)

    Chapman, H N; Barty, A; Marchesini, S; Noy, A; Cui, C; Howells, M R; Rosen, R; He, H; Spence, J H; Weierstall, U; Beetz, T; Jacobsen, C; Shapiro, D

    2005-08-19T23:59:59.000Z

    Coherent X-ray diffraction microscopy is a method of imaging non-periodic isolated objects at resolutions only limited, in principle, by the largest scattering angles recorded. We demonstrate X-ray diffraction imaging with high resolution in all three dimensions, as determined by a quantitative analysis of the reconstructed volume images. These images are retrieved from the 3D diffraction data using no a priori knowledge about the shape or composition of the object, which has never before been demonstrated on a non-periodic object. We also construct 2D images of thick objects with infinite depth of focus (without loss of transverse spatial resolution). These methods can be used to image biological and materials science samples at high resolution using X-ray undulator radiation, and establishes the techniques to be used in atomic-resolution ultrafast imaging at X-ray free-electron laser sources.

  5. High-resolution ab initio three-dimensional x-ray diffraction microscopy

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Chapman, Henry N.; Barty, Anton; Marchesini, Stefano; Noy, Aleksandr; Hau-Riege, Stefan P.; Cui, Congwu; Howells, Malcolm R.; Rosen, Rachel; He, Haifeng; Spence, John C.; Weierstall, Uwe; Beetz, Tobias; Jacobsen, Chris; Shapiro, David

    2006-01-01T23:59:59.000Z

    Coherent x-ray diffraction microscopy is a method of imaging nonperiodic isolated objects at resolutions limited, in principle, by only the wavelength and largest scattering angles recorded. We demonstrate x-ray diffraction imaging with high resolution in all three dimensions, as determined by a quantitative analysis of the reconstructed volume images. These images are retrieved from the three-dimensional diffraction data using no a priori knowledge about the shape or composition of the object, which has never before been demonstrated on a nonperiodic object. We also construct two-dimensional images of thick objects with greatly increased depth of focus (without loss of transverse spatial resolution). These methods can be used to image biological and materials science samples at high resolution with x-ray undulator radiation and establishes the techniques to be used in atomic-resolution ultrafast imaging at x-ray free-electron laser sources.

  6. angle diffraction studies: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    A. 3 DMSO-Induced Dehydration of DPPC Membranes Studied by X-ray Diffraction, Small-Angle Neutron Scattering, and Calorimetry Condensed Matter (arXiv) Summary: The influence of...

  7. Earth X-ray albedo for cosmic X-ray background radiation in the 1--1000 keV band

    E-Print Network [OSTI]

    E. Churazov; S. Sazonov; R. Sunyaev; M. Revnivtsev

    2008-02-11T23:59:59.000Z

    We present calculations of the reflection of the cosmic X-ray background (CXB) by the Earth's atmosphere in the 1--1000 keV energy range. The calculations include Compton scattering and X-ray fluorescent emission and are based on a realistic chemical composition of the atmosphere. Such calculations are relevant for CXB studies using the Earth as an obscuring screen (as was recently done by INTEGRAL). The Earth's reflectivity is further compared with that of the Sun and the Moon -- the two other objects in the Solar system subtending a large solid angle on the sky, as needed for CXB studies.

  8. Obliquity factors for {sup 60}Co and 4, 10, and 18 MV x rays for concrete, steel, and lead and angles of incidence between 0{degrees} and 70{degrees}

    SciTech Connect (OSTI)

    Biggs, P.J. [Harvard Medical School, Boston, MA (United States)

    1996-04-01T23:59:59.000Z

    The attenuation of {sup 60}Co gamma rays and photons of 4, 10, and 18 MV x-ray beams by concrete, steel, and lead has been studied using the Monte Carlo technique for angles of incidence 0{degrees}, 30{degrees}, 45{degrees}, 60{degrees}, and 70{degrees}. Transmission factors have been determined down to < 2 x 10{sup {minus}5} in all cases. The results show that deviation from the obliquity factor increases with angle but is not significant for angles {le} 45{degrees}. AT 70{degrees} angle of incidence and a transmission factor of 10{sup {minus}5}, the obliquity factor varies between 1.2 and 1.9 for concrete, between 1.4 and 1.7 for steel, and between 1.4 and 1.5 for lead for the range of energies investigated. This amounts to an additional 86 and 50 cm of concrete, 25 and 23 cm of steel, and 8 and 14 cm of lead for {sup 60}Co and 18 MV x rays, respectively. The results for {sup 60}Co is concrete and lead are in good agreement with previously published experimental work. Fits to the data using mathematical models allow reconstruction of all data curves to better than 1% on average and 7% in the worst single case. 9 refs., 14 figs., 6 tabs.

  9. X-Ray Data from the X-Ray Data Booklet Online

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Thompson, Albert C.; Attwood, David T.; Gullikson, Eric M.; Howells, Malcolm R.; Kortright, Jeffrey B.; Robinson, Arthur L.; Underwood, James H.; Kim, Kwang-Je; Kirz, Janos; Lindau, Ingolf; Pianetta, Piero; Winick, Herman; Williams, Gwyn P.; Scofield, James H.

    The original X-Ray Data Booklet, published in 1985, became a classic reference source. The online version has been significantly revised and updated to reflect today's science. Hundreds of pages of authoritative data provide the x-ray properties of elements, information on synchrotron radiation, scattering processes, optics and detectors, and other related calculations, formulas, and data tables.

  10. Transient x-ray diffraction and its application to materials science and x-ray optics

    SciTech Connect (OSTI)

    Hauer, A.A.; Kopp, R.; Cobble, J.; Kyrala, G.; Springer, R. [and others

    1997-12-01T23:59:59.000Z

    Time resolved x-ray diffraction and scattering have been applied to the measurement of a wide variety of physical phenomena from chemical reactions to shock wave physics. Interest in this method has heightened in recent years with the advent of versatile, high power, pulsed x-ray sources utilizing laser plasmas, electron beams and other methods. In this article, we will describe some of the fundamentals involved in time resolved x-ray diffraction, review some of the history of its development, and describe some recent progress in the field. In this article we will emphasize the use of laser-plasmas as the x-ray source for transient diffraction.

  11. Synaptic Arrangement of the Neuroligin/b-Neurexin ComplexRevealedbyX-RayandNeutronScattering

    E-Print Network [OSTI]

    Sandini, Giulio

    Structure Article Synaptic Arrangement of the Neuroligin/b-Neurexin ComplexRevealedbyX-RayandNeutronScattering away from the dimer in- terface. X-ray scattering and neutron contrast variation data show that two that associate with their presynaptic part- ners, the neurexins. Using small-angle X-ray scattering, we

  12. SANS -Small Angle Neutron Scattering Tcnica de difrao

    E-Print Network [OSTI]

    Loh, Watson

    SANS - Small Angle Neutron Scattering Técnica de difração informações sobre tamanho e forma de- Neutrons are created in the centre of the target station when the beam of high energy protons collides by evaporating nuclear particles, mainly neutrons, in all directions. Each proton produces approximately 15

  13. Chest x-Rays

    Broader source: Energy.gov [DOE]

    The B-reading is a special reading of a standard chest x-ray film performed by a physician certified by the National Institute for Occupational Safety and Health (NIOSH). The reading looks for changes on the chest x-ray that may indicate exposure and disease caused by agents such as asbestos or silica.

  14. hal-00154048,version1-12Jun2007 The new very small angle neutron scattering

    E-Print Network [OSTI]

    Boyer, Edmond

    hal-00154048,version1-12Jun2007 The new very small angle neutron scattering spectrometer The design and characteristics of the new very small angle neutron scattering spectrometer under construction in order to fill the gap between light scattering and classical small angle neutron scattering (SANS

  15. Investigations of the R5(SixGe1-x)4 Intermetallic Compounds by X-Ray Resonant Magnetic Scattering

    SciTech Connect (OSTI)

    Lizhi Tan

    2008-08-18T23:59:59.000Z

    The XRMS experiment on the Gd{sub 5}Ge{sub 4} system has shown that, below the Neel temperature, T{sub N} = 127 K, the magnetic unit cells is the same as the chemical unit cell. From azimuth scans and the Q dependence of the magnetic scattering, all three Gd sites in the structure were determined to be in the same magnetic space group Pnma. The magnetic moments are aligned along the c-axis and the c-components of the magnetic moments at the three different sites are equal. The ferromagnetic slabs are stacked antiferromagnetically along the b-direction. They found an unusual order parameter curve in Gd{sub 5}Ge{sub 4}. A spin-reorientation transition is a possibility in Gd{sub 5}Ge{sub 4}, which is similar to the Tb{sub 5}Ge{sub 4} case. Tb{sub 5}Ge{sub 4} possesses the same Sm{sub 5}Ge{sub 4}-type crystallographic structure and the same magnetic space group as Gd{sub 5}Ge{sub 4} does. The difference in magnetic structure is that Tb{sub 5}Ge{sub 4} has a canted one but Gd{sub 5}Ge{sub 4} has nearly a collinear one in the low temperature antiferromagnetic phase. The competition between the magneto-crystalline anisotropy and the nearest-neighbor magnetic exchange interactions may allow a 3-dimensional canted antiferromagnetic structure in Tb{sub 5}Ge{sub 4}. The spin-reorientation transition in both Gd{sub 5}Ge{sub 4} and Tb{sub 5}Ge{sub 4} may arise from the competition between the magnetic anisotropy from the spin-orbit coupling of the conduction electrons and the dipolar interactions anisotropy.

  16. X-ray laser

    DOE Patents [OSTI]

    Nilsen, Joseph (Livermore, CA)

    1991-01-01T23:59:59.000Z

    An X-ray laser (10) that lases between the K edges of carbon and oxygen, i.e. between 44 and 23 Angstroms, is provided. The laser comprises a silicon (12) and dysprosium (14) foil combination (16) that is driven by two beams (18, 20) of intense line focused (22, 24) optical laser radiation. Ground state nickel-like dysprosium ions (34) are resonantly photo-pumped to their upper X-ray laser state by line emission from hydrogen-like silicon ions (32). The novel X-ray laser should prove especially useful for the microscopy of biological specimens.

  17. Small angle neutron scattering from high impact polystyrene

    SciTech Connect (OSTI)

    Pringle, O.A.

    1981-01-01T23:59:59.000Z

    High impact polystyrene (HIPS) is a toughened plastic composed of a polystyrene matrix containing a few percent rubber in the form of dispersed 0.1 to 10 micron diameter rubber particles. Some commercial formulations of HIPS include the addition of a few percent mineral oil, which improves the toughness of the plastic. Little is known about the mechanism by which the mineral oil helps toughen the plastic. It is hypothesized that the oil is distributed only in the rubber particles, but whether this hypothesis is correct was not known prior to this work. The size of the rubber particles in HIPS and their neutron scattering length density contrast with the polystyrene matrix cause HIPS samples to scatter neutrons at small angles. The variation of this small angle neutron scattering (SANS) signal with mineral oil content has been used to determine the location of the oil in HIPS. The SANS spectrometer at the University of Missouri Research Reactor Facility (MURR) was used to study plastic samples similar in composition to commercial HIPS. The MURR SANS spectrometer is used to study the small angle scattering of a vertical beam of 4.75 A neutrons from solid and liquid samples. The scattered neutrons are detected in a 54 x 60 cm/sup 2/ position sensitive detector designed and built at MURR. A series of plastic samples of varying rubber and oil content and different rubber domain sizes and shapes were examined on the MURR SANS spectrometer. Analysis of the scattering patterns showed that the mineral oil is about eight to ten times more likely to be found in the rubber particles than in the polystyrene matrix. This result confirmed the hypothesis that the mineral oil is distributed primarily in the rubber particles.

  18. Radiation damage studies using small-angle neutron scattering

    SciTech Connect (OSTI)

    Albertini, G.; Rustichelli, F. [INFM, Ancona (Italy); Carsughi, F. [INFM, Ancona (Italy). Ist. di Scienze Fisiche; [KFA, Juelich (Germany). Inst. fuer Festkoerperforschung; Coppola, R. [ENEA-Casaccia, Roma (Italy); Stefanon, M. [ENEA, Bologna (Italy)

    1996-12-31T23:59:59.000Z

    This contribution reviews a number of small-angle neutron scattering (SANS) studies of irradiated metals and steels of relevance to fission and fusion technology. Information obtainable by SANS measurements is recalled with special reference to the determination of the size distribution function of the microstructural inhomogeneities. The selected examples concern studies of the main kinds of radiation defects: voids, precipitates, He-bubbles. Some recent results obtained on structural materials for the first-wall of fusion reactors are also presented.

  19. X-ray grid-detector apparatus

    DOE Patents [OSTI]

    Boone, John M. (Folsom, CA); Lane, Stephen M. (Oakland, CA)

    1998-01-27T23:59:59.000Z

    A hybrid grid-detector apparatus for x-ray systems wherein a microchannel plate structure has an air-interspaced grid portion and a phosphor/optical fluid-filled grid portion. The grids are defined by multiple adjacent channels separated by lead-glass septa. X-rays entering the air-interspaced grid portion at an angle of impingement upon the septa are attenuated, while non-impinging x-rays pass through to the phosphor/fluid filled portion. X-ray energy is converted to luminescent energy in the phosphor/fluid filled portion and the resultant beams of light are directed out of the phosphor/optical fluid filled portion to an imaging device.

  20. Monitoring simultaneously the growth of nanoparticles and aggregates by in situ ultra-small-angle x-ray scattering

    E-Print Network [OSTI]

    Beaucage, Gregory

    spectroscopy and thermophoretic sampling was used to visualize particle growth with height above the burner

  1. Structural analysis of flexible proteins in solution by Small Angle X-ray Scattering combined with crystallography

    E-Print Network [OSTI]

    Tsutakawa, Susan E.; Hura, Greg L.; Frankel, Ken A.; Cooper, Priscilla K.; Tainer, John A.

    2006-01-01T23:59:59.000Z

    and V.N. Uversky, 2005. Flexible nets - The roles ofand T. Ellenberger, 2006. A flexible interface between DNAStructural analysis of flexible proteins in solution by

  2. X-ray imaging crystal spectrometer for extended X-ray sources

    DOE Patents [OSTI]

    Bitter, Manfred L. (Princeton, NJ); Fraenkel, Ben (Jerusalem, IL); Gorman, James L. (Bordentown, NJ); Hill, Kenneth W. (Lawrenceville, NJ); Roquemore, A. Lane (Cranbury, NJ); Stodiek, Wolfgang (Princeton, NJ); von Goeler, Schweickhard E. (Princeton, NJ)

    2001-01-01T23:59:59.000Z

    Spherically or toroidally curved, double focusing crystals are used in a spectrometer for X-ray diagnostics of an extended X-ray source such as a hot plasma produced in a tokomak fusion experiment to provide spatially and temporally resolved data on plasma parameters using the imaging properties for Bragg angles near 45. For a Bragg angle of 45.degree., the spherical crystal focuses a bundle of near parallel X-rays (the cross section of which is determined by the cross section of the crystal) from the plasma to a point on a detector, with parallel rays inclined to the main plain of diffraction focused to different points on the detector. Thus, it is possible to radially image the plasma X-ray emission in different wavelengths simultaneously with a single crystal.

  3. Apparatus for generating x-ray holograms

    DOE Patents [OSTI]

    Rhodes, C.K.; Boyer, K.; Solem, J.C.; Haddad, W.S.

    1990-09-11T23:59:59.000Z

    Apparatus for x-ray microholography of living biological materials. A Fourier transform holographic configuration is described as being most suitable for the 3-dimensional recording of the physical characteristics of biological specimens. The use of a spherical scatterer as a reference and a charge-coupled device two-dimensional detector array placed in the forward direction relative to the incident x-radiation for viewing electromagnetic radiation simultaneously scattered from both the specimen and the reference scatterer permits the ready reconstruction of the details of the specimen from the fringe pattern detected by the charge-coupled device. For example, by using a nickel reference scatter at 4.5 nm, sufficient reference illumination is provided over a wide enough angle to allow similar resolution in both transverse and longitudinal directions. Both laser and synchrotron radiation sources are feasible for generating microholographs. Operation in the water window (2.4 to 4.5 nm) should provide maximum contrast for features of the specimen and spatial resolution on the order of the wavelength of x-radiation should be possible in all three dimensions, which is sufficient for the visualization of many biological features. It is anticipated that the present apparatus will find utility in other areas as well where microscopic physical details of a specimen are important. A computational procedure which enables the holographic data collected by the detector to be used to correct for misalignments introduced by inexact knowledge of the relative positions of the spherical reference scatterer and the sample under investigation has been developed. If the correction is performed prior to reconstruction, full compensation can be achieved and a faithfully reconstructed image produced. 7 figs.

  4. Apparatus for generating x-ray holograms

    DOE Patents [OSTI]

    Rhodes, Charles K. (Chicago, IL); Boyer, Keith (Los Alamos, NM); Solem, Johndale C. (Los Alamos, NM); Haddad, Waleed S. (Chicago, IL)

    1990-01-01T23:59:59.000Z

    Apparatus for x-ray microholography of living biological materials. A Fourier transform holographic configuration is described as being most suitable for the 3-dimensional recording of the physical characteristics of biological specimens. The use of a spherical scatterer as a reference and a charge-coupled device two-dimensional detector array placed in the forward direction relative to the incident x-radiation for viewing electromagnetic radiation simultaneously scattered from both the specimen and the reference scatterer permits the ready reconstruction of the details of the specimen from the fringe pattern detected by the charge-coupled device. For example, by using a nickel reference scatter at 4.5 nm, sufficient reference illumination is provided over a wide enough angle to allow similar resolution in both transverse and longitudinal directions. Both laser and synchrotron radiation sources are feasible for generating microholographs. Operation in the water window (2.4 to 4.5 nm) should provide maximum contrast for features of the specimen and spatial resolution on the order of the wavelength of x-radiation should be possible in all three dimensions, which is sufficient for the visualization of many biological features. It is anticipated that the present apparatus will find utility in other areas as well where microscopic physical details of a specimen are important. A computational procedure which enables the holographic data collected by the detector to be used to correct for misalignments introduced by inexact knowledge of the relative positions of the spherical reference scatterer and the sample under investigation has been developed. If the correction is performed prior to reconstruction, full compensation can be achieved and a faithfully reconstructed image produced.

  5. X-ray beam finder

    DOE Patents [OSTI]

    Gilbert, H.W.

    1983-06-16T23:59:59.000Z

    An X-ray beam finder for locating a focal spot of an X-ray tube includes a mass of X-ray opaque material having first and second axially-aligned, parallel-opposed faces connected by a plurality of substantially identical parallel holes perpendicular to the faces and a film holder for holding X-ray sensitive film tightly against one face while the other face is placed in contact with the window of an X-ray head.

  6. Compton backscattered collimated x-ray source

    DOE Patents [OSTI]

    Ruth, R.D.; Huang, Z.

    1998-10-20T23:59:59.000Z

    A high-intensity, inexpensive and collimated x-ray source is disclosed for applications such as x-ray lithography is disclosed. An intense pulse from a high power laser, stored in a high-finesse resonator, repetitively collides nearly head-on with and Compton backscatters off a bunched electron beam, having relatively low energy and circulating in a compact storage ring. Both the laser and the electron beams are tightly focused and matched at the interaction region inside the optical resonator. The laser-electron interaction not only gives rise to x-rays at the desired wavelength, but also cools and stabilizes the electrons against intrabeam scattering and Coulomb repulsion with each other in the storage ring. This cooling provides a compact, intense bunch of electrons suitable for many applications. In particular, a sufficient amount of x-rays can be generated by this device to make it an excellent and flexible Compton backscattered x-ray (CBX) source for high throughput x-ray lithography and many other applications. 4 figs.

  7. Compton backscattered collmated X-ray source

    DOE Patents [OSTI]

    Ruth, Ronald D. (Woodside, CA); Huang, Zhirong (Stanford, CA)

    2000-01-01T23:59:59.000Z

    A high-intensity, inexpensive and collimated x-ray source for applications such as x-ray lithography is disclosed. An intense pulse from a high power laser, stored in a high-finesse resonator, repetitively collides nearly head-on with and Compton backscatters off a bunched electron beam, having relatively low energy and circulating in a compact storage ring. Both the laser and the electron beams are tightly focused and matched at the interaction region inside the optical resonator. The laser-electron interaction not only gives rise to x-rays at the desired wavelength, but also cools and stabilizes the electrons against intrabeam scattering and Coulomb repulsion with each other in the storage ring. This cooling provides a compact, intense bunch of electrons suitable for many applications. In particular, a sufficient amount of x-rays can be generated by this device to make it an excellent and flexible Compton backscattered x-ray (CBX) source for high throughput x-ray lithography and many other applications.

  8. Compton backscattered collimated x-ray source

    DOE Patents [OSTI]

    Ruth, Ronald D. (Woodside, CA); Huang, Zhirong (Stanford, CA)

    1998-01-01T23:59:59.000Z

    A high-intensity, inexpensive and collimated x-ray source for applications such as x-ray lithography is disclosed. An intense pulse from a high power laser, stored in a high-finesse resonator, repetitively collides nearly head-on with and Compton backscatters off a bunched electron beam, having relatively low energy and circulating in a compact storage ring. Both the laser and the electron beams are tightly focused and matched at the interaction region inside the optical resonator. The laser-electron interaction not only gives rise to x-rays at the desired wavelength, but also cools and stabilizes the electrons against intrabeam scattering and Coulomb repulsion with each other in the storage ring. This cooling provides a compact, intense bunch of electrons suitable for many applications. In particular, a sufficient amount of x-rays can be generated by this device to make it an excellent and flexible Compton backscattered x-ray (CBX) source for high throughput x-ray lithography and many other applications.

  9. X-Ray Diagnostics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengtheningWildfires may contribute more toConsensusX-Ray Diagnostics X-Ray

  10. Comparison of collimation systems for small-angle neutron scattering

    SciTech Connect (OSTI)

    Seeger, P.A.

    1985-01-01T23:59:59.000Z

    It is shown by simple first-order geometric arguments that for a given resolution, the flux on sample in a small-angle scattering instrument is independent of the form of the collimator or of the length of the instrument. Count rate may be increased by increasing the sample size, through the use of multi-aperture systems. In second order, it is shown to be advantageous to place the beam defining elements as close as possible to the source and the sample. The multiple-pinhole system gives maximum flux on small samples but has non-uniform illumination so that intensity increases only about half as fast as sample area. Soller slits and continuous tubes from source to sample were also considered, but neutron scattering and reflection from surfaces generate a large halo. Monte-Carlo simulations confirm these results, with the conclusion that the optimum collimator configuration is the multiple-pinhole system. 4 refs., 4 figs.

  11. Small angle neutron scattering study of Linde 80 RPV welds

    SciTech Connect (OSTI)

    Wirth, B.D.; Odette, G.R.; Lucas, G.E. [Univ. of California, Santa Barbara, CA (United States). Dept. of Mechanical and Environmental Engineering; Pavinich, W.A. [Framatome Technologies Inc., Knoxville, TN (United States); Spooner, S.E. [Oak Ridge National Lab., TN (United States). Solid state Div.

    1999-10-01T23:59:59.000Z

    Small angle neutron scattering (SANS) results are presented for Linde 80 welds irradiated, as part of the B and W Owners Group Integrated Surveillance Program, at low fluxes (<10{sup 15} n/m{sup 2}-s) to fluences from 0.29 to 3.5 {times} 10{sup 23} n/m{sup 2} (E > 1 MeV) at irradiation temperatures from 276 to 292 C. The welds all contain about 0.6 Ni (all composition units are in wt.%), 0.009 to 0.18 P and 0.05 to 0.28 Cu. In the welds with significant amounts of copper (>0.2 Cu) the measured defect scattering cross sections were consistent with either: (a) copper rich precipitates (CRPs) alloyed with manganese and nickel; or (b) dominant CRP scattering, plus a weak contribution from so-called matrix defect features. Similar weak scattering was observed in a low copper (0.06 Cu) weld. The identity of matrix defect features cannot be determined from the SANS data alone, but the scattering is consistent with the presence of subnanometer vacancy cluster-solute complexes. The general character of the CRPs, and the trends in their number density, volume fraction and average radius as a function of fluence and irradiation temperature, are very similar to those observed in a wide range of pressure vessel-type steels irradiated in test reactors at intermediate to high flux. The SANS data in the surveillance welds is also in unity with: (a) thermodynamic-kinetic radiation enhanced diffusion models of CRP evolution; (b) mechanical property changes, including predictions of the correlations of the surveillance data base; and (c) an atomic scale, atom probe field ion microscopy study into the nanostructure-chemistry of a CRP.

  12. Residual stress measurement using X-ray diffraction

    E-Print Network [OSTI]

    Anderoglu, Osman

    2005-02-17T23:59:59.000Z

    -rays..............................................................................................16 2.4. Bragg's Law ..........................................................................................................18 2.5. Diffractometer Geometry... Figure 2.2 Schematic showing the basic components of a modern x-ray tube. Beryllium window is highly transparent to x-rays...............................15 Figure 2.3 Coherent scattering from an electron to a point P...

  13. Theoretical standards in x-ray spectroscopies

    SciTech Connect (OSTI)

    Not Available

    1992-01-01T23:59:59.000Z

    We propose to extend our state-of-the-art, ab initio XAFS (X-ray absorption fine structure) codes, FEFF. Our current work has been highly successful in achieving accurate, user-friendly XAFS standards, exceeding the performance of both tabulated standards and other codes by a considerable margin. We now propose to add the capability to treat more complex materials. This includes multiple-scattering, polarization dependence, an approximate treatment of XANES (x-ray absorption near edge structure), and other improvements. We also plan to adapt FEFF to other spectroscopies, e.g. photoelectron diffraction (PD) and diffraction anomalous fine structure (DAFS).

  14. Small angle neutron scattering on periodically deformed polymers A. R. Rennie

    E-Print Network [OSTI]

    Boyer, Edmond

    765 Small angle neutron scattering on periodically deformed polymers A. R. Rennie Institut für Phys-768 SEPTEMBRE 1984, 1. Introduction. Neutron scattering has proved a useful tool for the investigation of a wide time for a small angle neutron scattering spectrum is several minutes. Obser- vation on rapidly

  15. High temperature furnaces for small and large angle neutron scattering of disordered materials

    E-Print Network [OSTI]

    Boyer, Edmond

    725 High temperature furnaces for small and large angle neutron scattering of disordered materials and small angle neutron scattering (SANS) experiments respectively. They are vacuum furnaces with a thin maintained in a tantalum box. In a neutron beam, the furnaces produce a very low scattering level (without

  16. Solvent Entrainment in and Flocculation of Asphaltenic Aggregates Probed by Small-Angle Neutron Scattering

    E-Print Network [OSTI]

    Kilpatrick, Peter K.

    -Angle Neutron Scattering Keith L. Gawrys, George A. Blankenship, and Peter K. Kilpatrick* Department of ChemicalVed September 14, 2005. In Final Form: January 30, 2006 While small-angle neutron scattering (SANS) has proven to the scattering intensity curves were performed using the Guinier approximation, the Ornstein- Zernike (or Zimm

  17. X-ray lithography using holographic images

    DOE Patents [OSTI]

    Howells, Malcolm S. (Berkeley, CA); Jacobsen, Chris (Sound Beach, NY)

    1997-01-01T23:59:59.000Z

    Methods for forming X-ray images having 0.25 .mu.m minimum line widths on X-ray sensitive material are presented. A holgraphic image of a desired circuit pattern is projected onto a wafer or other image-receiving substrate to allow recording of the desired image in photoresist material. In one embodiment, the method uses on-axis transmission and provides a high flux X-ray source having modest monochromaticity and coherence requirements. A layer of light-sensitive photoresist material on a wafer with a selected surface is provided to receive the image(s). The hologram has variable optical thickness and variable associated optical phase angle and amplitude attenuation for transmission of the X-rays. A second embodiment uses off-axis holography. The wafer receives the holographic image by grazing incidence reflection from a hologram printed on a flat metal or other highly reflecting surface or substrate. In this second embodiment, an X-ray beam with a high degree of monochromaticity and spatial coherence is required.

  18. X-ray lithography using holographic images

    DOE Patents [OSTI]

    Howells, M.S.; Jacobsen, C.

    1997-03-18T23:59:59.000Z

    Methods for forming X-ray images having 0.25 {micro}m minimum line widths on X-ray sensitive material are presented. A holographic image of a desired circuit pattern is projected onto a wafer or other image-receiving substrate to allow recording of the desired image in photoresist material. In one embodiment, the method uses on-axis transmission and provides a high flux X-ray source having modest monochromaticity and coherence requirements. A layer of light-sensitive photoresist material on a wafer with a selected surface is provided to receive the image(s). The hologram has variable optical thickness and variable associated optical phase angle and amplitude attenuation for transmission of the X-rays. A second embodiment uses off-axis holography. The wafer receives the holographic image by grazing incidence reflection from a hologram printed on a flat metal or other highly reflecting surface or substrate. In this second embodiment, an X-ray beam with a high degree of monochromaticity and spatial coherence is required. 15 figs.

  19. Characterization of a Fe/Y{sub 2}O{sub 3} metal/oxide interface using neutron and x-ray scattering

    SciTech Connect (OSTI)

    Watkins, E. B.; Majewski, J., E-mail: demkowicz@mit.edu, E-mail: jarek@lanl.gov [Lujan Neutron Scattering Center, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Kashinath, A. [Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Computational Modeling Technology, Aramco Research Center—Boston, Cambridge, Massachusetts 02139 (United States); Wang, P. [Lujan Neutron Scattering Center, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Intel Corporation, Hillsboro, Oregon, 97006 (United States); Baldwin, J. K. [Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Demkowicz, M. J., E-mail: demkowicz@mit.edu, E-mail: jarek@lanl.gov [Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

    2014-07-28T23:59:59.000Z

    The structure of metal/oxide interfaces is important to the radiation resistance of oxide dispersion-strengthened steels. We find evidence of gradual variations in stoichiometry and magnetization across a Fe/Y{sub 2}O{sub 3} metal/oxide heterophase interface using neutron and x-ray reflectometry. These findings suggest that the Fe/Y{sub 2}O{sub 3} interface is a transitional zone approximately ?64?Å-thick containing mixtures or compounds of Fe, Y, and O. Our results illustrate the complex chemical and magnetic nature of Fe/oxide interfaces and demonstrate the utility of combined neutron and x-ray techniques as tools for characterizing them.

  20. Epoxy replication for Wolter x-ray microscope fabrication

    SciTech Connect (OSTI)

    Priedhorsky, W.

    1981-01-01T23:59:59.000Z

    An epoxy replica of a test piece designed to simulate a Wolter x-ray microscope geometry showed no loss of x-ray reflectivity or resolution, compared to the original. The test piece was a diamond-turned cone with 1.5/sup 0/ half angle. A flat was fly-cut on one side, then super- and conventionally polished. The replica was separated at the 1.5/sup 0/-draft angle, simulating a shallow angle Wolter microscope geometry. A test with 8.34 A x rays at 0.9/sup 0/ grazing angle showed a reflectivity of 67% for the replica flat surface, and 70% for the original. No spread of the reflected beam was observed with a 20-arc second wide test beam. This test verifies the epoxy replication technique for production of Wolter x-ray microscopes.

  1. Quantitative electron density characterization of soft tissue substitute plastic materials using grating-based x-ray phase-contrast imaging

    SciTech Connect (OSTI)

    Sarapata, A.; Chabior, M.; Zanette, I.; Pfeiffer, F. [Lehrstuhl für Biomedizinische Physik, Physik-Department and Institut für Medizintechnik, Technische Universität München, 85748 Garching (Germany); Cozzini, C.; Sperl, J. I.; Bequé, D. [GE Global Research, 85748 Garching (Germany); Langner, O.; Coman, J. [QRM GmbH, Möhrendorf (Germany); Ruiz-Yaniz, M. [Lehrstuhl für Biomedizinische Physik, Physik-Department and Institut für Medizintechnik, Technische Universität München, 85748 Garching (Germany); European Synchrotron Radiation Facility, Grenoble (France)

    2014-10-15T23:59:59.000Z

    Many scientific research areas rely on accurate electron density characterization of various materials. For instance in X-ray optics and radiation therapy, there is a need for a fast and reliable technique to quantitatively characterize samples for electron density. We present how a precise measurement of electron density can be performed using an X-ray phase-contrast grating interferometer in a radiographic mode of a homogenous sample in a controlled geometry. A batch of various plastic materials was characterized quantitatively and compared with calculated results. We found that the measured electron densities closely match theoretical values. The technique yields comparable results between a monochromatic and a polychromatic X-ray source. Measured electron densities can be further used to design dedicated X-ray phase contrast phantoms and the additional information on small angle scattering should be taken into account in order to exclude unsuitable materials.

  2. Reactive sputter magnetron reactor for preparation of thin films and simultaneous in situ structural study by X-ray diffraction

    SciTech Connect (OSTI)

    Buergi, J.; Molleja, J. Garcia; Feugeas, J. [Instituto de Fisica Rosario (CONICET-UNR), Bv. 27 de Febrero 210 bis, S2000EZP Rosario (Argentina); Neuenschwander, R. [Laboratorio Nacional Luz Sincrotron (LNLS), Caixa Postal 6192, CEP13083-970 Campinas (Brazil); Kellermann, G. [Departamento de Fisica (Universidade Federal do Parana), Caixa Postal 19044, CEP81531-990 Curitiba (Brazil); Craievich, A. F. [Instituto de Fisica (Universidade de Sao Paulo), Rua do Matao Travessa R 187, CEP05508-090 Sao Paulo (Brazil)

    2013-01-15T23:59:59.000Z

    The purpose of the designed reactor is (i) to obtain polycrystalline and/or amorphous thin films by controlled deposition induced by a reactive sputtering magnetron and (ii) to perform a parallel in situ structural study of the deposited thin films by X-ray diffraction, in real time, during the whole growth process. The designed reactor allows for the control and precise variation of the relevant processing parameters, namely, magnetron target-to-sample distance, dc magnetron voltage, and nature of the gas mixture, gas pressure and temperature of the substrate. On the other hand, the chamber can be used in different X-ray diffraction scanning modes, namely, {theta}-2{theta} scanning, fixed {alpha}-2{theta} scanning, and also low angle techniques such as grazing incidence small angle X-ray scattering and X-ray reflectivity. The chamber was mounted on a standard four-circle diffractometer located in a synchrotron beam line and first used for a preliminary X-ray diffraction analysis of AlN thin films during their growth on the surface of a (100) silicon wafer.

  3. Bomb Detection Using Backscattered X-Rays

    SciTech Connect (OSTI)

    Jacobs, J.; Lockwood, G.; Selph, M; Shope, S.; Wehlburg, J.

    1998-10-01T23:59:59.000Z

    Bomb Detection Using Backscattered X-rays* Currently the most common method to determine the contents of a package suspected of containing an explosive device is to use transmission radiography. This technique requires that an x-ray source and film be placed on opposite sides of the package. This poses a problem if the pachge is placed so that only one side is accessible, such as against a wall. There is also a threat to persomel and property since exTlosive devices may be "booby trapped." We have developed a method to x-ray a paclage using backscattered x-rays. This procedure eliminates the use of film behind the target. All of the detection is done from the same side as the source. When an object is subjected to x-rays, some of them iare scattered back towards the source. The backscattenng of x-rays is propordoml to the atomic number (Z) of the material raised to the 4.1 power. This 24"' dependence allows us to easily distinguish between explosives, wires, timer, batteries, and other bomb components. Using transmission radiography-to image the contents of an unknown package poses some undesirable risks. The object must have an x-ray film placed on the side opposite the x-ray source; this cannot be done without moving the package if it has been placed firmly against a wall or pillar. Therefore it would be extremely usefid to be able to image the contents of a package from only one side, without ever having to disturb the package itself. where E is the energy of the incoming x-ray. The volume of x-rays absorbed is important because it is, of course, directly correlated to the intensity of x-mys that will be scattered. Most of the x-rays that scatter will do so in a genemlly forward direction; however, a small percentage do scatter in a backward direction. Figure 1 shows a diagram of the various fates of x-rays directed into an object. The package that was examined in this ex~enment was an attache case made of pressed fiberboardwith a vinyl covering. It was approxirmtely 36 cm wide by 51 cm long by 13 cm deep. The case was placed on an aluminum sheet under the x-ray source. Because of the laborato~ setup, the attache case was rastered in the y-coordinate direction, while the x-ray source mstered in the x-coordinate direction. However, for field use, the x-ray source would of course raster in both the x- and y-coordinate directions, while the object under interrogation would remain stationary and undisturbed. A mobile system for use by law enforcement agencies or bomb disposal squads needs to be portable and somewhat durable. A 300 kV x-ray source should be sufficient for the task requirements and can be mounted on a mobile system. A robotic carriage could be used to transport the x-ray source and the CCD camera to the proximity of the suspect package. The controlling and data analyzing elements of the system' could then be maintained at a &tie distance from the possible explosive. F@re 8 shows a diagram of a conceptual design of a possible system for this type of use. The use of backscattered x-rays for interrogation of packages that may contain explosive devices has been shown to be feasible inthelaboratory. Usinga 150kVx-ray source anddetectors consisting of plastic scintillating material, all bomb components including the wiring were detectable. However, at this time the process requires more time than is desirable for the situations in which it will most likely be needed. Further development of the technology using CCD cameras, rather than the plastic stint illator detectors, shows promise of leading to a much faster system, as well as one with better resolution. Mounting the x- ray source and the CCD camera on a robotic vehicle while keeping the controlling and analyzing components and the opemting personnel a safe distance away from the suspect package will allow such a package to be examined at low risk to human life.

  4. X-ray lithography source

    DOE Patents [OSTI]

    Piestrup, Melvin A. (Woodside, CA); Boyers, David G. (Mountain View, CA); Pincus, Cary (Sunnyvale, CA)

    1991-01-01T23:59:59.000Z

    A high-intensity, inexpensive X-ray source for X-ray lithography for the production of integrated circuits. Foil stacks are bombarded with a high-energy electron beam of 25 to 250 MeV to produce a flux of soft X-rays of 500 eV to 3 keV. Methods of increasing the total X-ray power and making the cross section of the X-ray beam uniform are described. Methods of obtaining the desired X-ray-beam field size, optimum frequency spectrum and elminating the neutron flux are all described. A method of obtaining a plurality of station operation is also described which makes the process more efficient and economical. The satisfying of these issues makes transition radiation an exellent moderate-priced X-ray source for lithography.

  5. X-ray lithography source

    DOE Patents [OSTI]

    Piestrup, M.A.; Boyers, D.G.; Pincus, C.

    1991-12-31T23:59:59.000Z

    A high-intensity, inexpensive X-ray source for X-ray lithography for the production of integrated circuits is disclosed. Foil stacks are bombarded with a high-energy electron beam of 25 to 250 MeV to produce a flux of soft X-rays of 500 eV to 3 keV. Methods of increasing the total X-ray power and making the cross section of the X-ray beam uniform are described. Methods of obtaining the desired X-ray-beam field size, optimum frequency spectrum and eliminating the neutron flux are all described. A method of obtaining a plurality of station operation is also described which makes the process more efficient and economical. The satisfying of these issues makes transition radiation an excellent moderate-priced X-ray source for lithography. 26 figures.

  6. Dose, exposure time, and resolution in Serial X-ray Crystallography

    SciTech Connect (OSTI)

    Starodub, D; Rez, P; Hembree, G; Howells, M; Shapiro, D; Chapman, H N; Fromme, P; Schmidt, K; Weierstall, U; Doak, R B; Spence, J C

    2007-03-22T23:59:59.000Z

    Using detailed simulation and analytical models, the exposure time is estimated for serial crystallography, where hydrated laser-aligned proteins are sprayed across a continuous synchrotron beam. The resolution of X-ray diffraction microscopy is limited by the maximum dose that can be delivered prior to sample damage. In the proposed Serial Crystallography method, the damage problem is addressed by distributing the total dose over many identical hydrated macromolecules running continuously in a single-file train across a continuous X-ray beam, and resolution is then limited only by the available fluxes of molecules and X-rays. Orientation of the diffracting molecules is achieved by laser alignment. We evaluate the incident X-ray fluence (energy/area) required to obtain a given resolution from (1) an analytical model, giving the count rate at the maximum scattering angle for a model protein, (2) explicit simulation of diffraction patterns for a GroEL-GroES protein complex, and (3) the frequency cut off of the transfer function following iterative solution of the phase problem, and reconstruction of a density map in the projection approximation. These calculations include counting shot noise and multiple starts of the phasing algorithm. The results indicate the number of proteins needed within the beam at any instant for a given resolution and X-ray flux. We confirm an inverse fourth power dependence of exposure time on resolution, with important implications for all coherent X-ray imaging. We find that multiple single-file protein beams will be needed for sub-nanometer resolution on current third generation synchrotrons, but not on fourth generation designs, where reconstruction of secondary protein structure at a resolution of 7 {angstrom} should be possible with short (below 100 s) exposures.

  7. X-ray spectrometry

    SciTech Connect (OSTI)

    Markowicz, A.A.; Van Grieken, R.E.

    1986-04-01T23:59:59.000Z

    In the period under review, i.e, through 1984 and 1985, some 600 articles on XRS (X-ray spectrometry) were published; most of these have been scanned and the most fundamental ones are discussed. All references will refer to English-language articles, unless states otherwise. Also general books have appeared on quantitative EPXMA (electron-probe X-ray microanalysis) and analytical electron microscopy (AEM) as well as an extensive review on the application of XRS to trace analysis of environmental samples. In the period under review no radically new developments have been seen in XRS. However, significant improvements have been made. Gain in intensities has been achieved by more efficient excitation, higher reflectivity of dispersing media, and better geometry. Better understanding of the physical process of photon- and electron-specimen interactions led to complex but more accurate equations for correction of various interelement effects. Extensive use of micro- and minicomputers now enables fully automatic operation, including qualitative analysis. However, sample preparation and presentation still put a limit to further progress. Although some authors find XRS in the phase of stabilization or even stagnation, further gradual developments are expected, particularly toward more dedicated equipment, advanced automation, and image analysis systems. Ways are outlined in which XRS has been improved in the 2 last years by excitation, detection, instrumental, methodological, and theoretical advances. 340 references.

  8. Small angle elastic scattering of protons off of spinless nuclei

    SciTech Connect (OSTI)

    Ling, A.G.

    1988-07-01T23:59:59.000Z

    Elastic differential cross sections and analyzing powers for 800 MeV protons incident on /sup 12/C, /sup 40/Ca, and /sup 208/Pb in the momentum transfer range 20 MeV/c < q < 130 MeV/c have been measured. The data was taken with the High Resolution Spectrometer (HRS) at the Los Alamos Meson Physics Facility. Special delay-line drift chambers with dead regions for the beam to pass through them were used to obtain the data. Through the interference of the Coulomb and nuclear contributions to the differential cross section in the small angle region, the ratio of the real to imaginary part of the forward nuclear amplitude ..cap alpha../sub n/(0) = Ref/sub n/(0)/Imf/sub n/(0) is extracted. The importance of knowing this quantity at lower energies in order to study the differences between relativistic and non-relativistic scattering theories is discussed. 130 refs., 60 figs., 12 tabs.

  9. Small angle neutron scattering from single-wall carbon nanotube suspensions: evidence for isolated

    E-Print Network [OSTI]

    Wang, Howard "Hao"

    Small angle neutron scattering from single-wall carbon nanotube suspensions: evidence for isolated online: Abstract We report small angle neutron scattering (SANS) from dilute suspensions of purified University, Houghton, MI 49931, USA e NIST Center for Neutron Research, National Institute of Standards

  10. Salt-Dependent Compaction of Di-and Trinucleosomes Studied by Small-Angle Neutron Scattering

    E-Print Network [OSTI]

    Langowski, Jörg

    Salt-Dependent Compaction of Di- and Trinucleosomes Studied by Small-Angle Neutron Scattering, Germany, and Institut Laue-Langevin Grenoble, F-38042 Grenoble, France ABSTRACT Using small-angle neutron scattering (SANS), we have measured the salt-dependent static structure factor of di- and trinucleosomes from

  11. Small angle neutron scattering (SANS) under non-equilibrium conditions R. C. Oberthr

    E-Print Network [OSTI]

    Boyer, Edmond

    663 Small angle neutron scattering (SANS) under non-equilibrium conditions R. C. Oberthür Institut with the times obtained from quasi- elastic neutron and light scattering, which yield information about neutrons aux petits angles (DNPA) pour l'étude des systèmes hors d'équi- libre thermodynamique est

  12. Miniature x-ray source

    DOE Patents [OSTI]

    Trebes, James E. (Livermore, CA); Stone, Gary F. (Livermore, CA); Bell, Perry M. (Tracy, CA); Robinson, Ronald B. (Modesto, CA); Chornenky, Victor I. (Minnetonka, MN)

    2002-01-01T23:59:59.000Z

    A miniature x-ray source capable of producing broad spectrum x-ray emission over a wide range of x-ray energies. The miniature x-ray source comprises a compact vacuum tube assembly containing a cathode, an anode, a high voltage feedthru for delivering high voltage to the anode, a getter for maintaining high vacuum, a connection for an initial vacuum pump down and crimp-off, and a high voltage connection for attaching a compact high voltage cable to the high voltage feedthru. At least a portion of the vacuum tube wall is highly x-ray transparent and made, for example, from boron nitride. The compact size and potential for remote operation allows the x-ray source, for example, to be placed adjacent to a material sample undergoing analysis or in proximity to the region to be treated for medical applications.

  13. X-Ray Diffraction Microscopy of Magnetic Structures

    SciTech Connect (OSTI)

    Turner, J.; Lima, E.; Huang, X.; Krupin, O.; Seu, K.; Parks, D.; Kevan, S.; Kisslinger, K.; McNulty, I.; Gambino, R.; Mangin, S.; Roy, S. and Fischer, P.

    2011-07-14T23:59:59.000Z

    We report the first proof-of-principle experiment of iterative phase retrieval from magnetic x-ray diffraction. By using the resonant x-ray excitation process and coherent x-ray scattering, we show that linearly polarized soft x rays can be used to image both the amplitude and the phase of magnetic domain structures. We recovered the magnetic structure of an amorphous terbium-cobalt thin film with a spatial resolution of about 75 nm at the Co L{sub 3} edge at 778 eV. In comparison with soft x-ray microscopy images recorded with Fresnel zone plate optics at better than 25 nm spatial resolution, we find qualitative agreement in the observed magnetic structure.

  14. X-ray and neutron scattering studies of the Rb?MnF? and Cu?â??õxMgx̳GeO? in an external magnetic field

    E-Print Network [OSTI]

    Christianson, Rebecca J. (Rebecca Jean), 1973-

    2001-01-01T23:59:59.000Z

    This thesis presents results of two scattering studies of low dimensional magnetic materials. The first is a neutron scattering study of Rb2MnF4, a nearly ideal two-dimensional square lattice Heisenberg antiferromagnet ...

  15. Angle-resolved scattering spectroscopy of explosives using an external cavity quantum cascade laser

    SciTech Connect (OSTI)

    Suter, Jonathan D.; Bernacki, Bruce E.; Phillips, Mark C.

    2012-04-01T23:59:59.000Z

    Investigation of angle-resolved scattering from solid explosives residues on a car door for non-contact sensing geometries. Illumination with a mid-infrared external cavity quantum cascade laser tuning between 7 and 8 microns was detected both with a sensitive single point detector and a hyperspectral imaging camera. Spectral scattering phenomena were discussed and possibilities for hyperspectral imaging at large scattering angles were outlined.

  16. Neutron and X-ray experiments at high temperature P. Aldebert (*)

    E-Print Network [OSTI]

    Boyer, Edmond

    neutron scattering have appeared as power- ful tools to get information, mainly structural temperature scattering devices compared to X-rays. At the present time thermal neutron high flux reactors be investigated by neutron scattering.

  17. Automated high pressure cell for pressure jump x-ray diffraction

    SciTech Connect (OSTI)

    Brooks, Nicholas J.; Gauthe, Beatrice L. L. E.; Templer, Richard H.; Ces, Oscar; Seddon, John M. [Department of Chemistry, Imperial College London, South Kensington Campus, London SW7 2AZ (United Kingdom); Terrill, Nick J. [Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE (United Kingdom); Rogers, Sarah E. [ISIS, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX (United Kingdom)

    2010-06-15T23:59:59.000Z

    A high pressure cell for small and wide-angle x-ray diffraction measurements of soft condensed matter samples has been developed, incorporating a fully automated pressure generating network. The system allows both static and pressure jump measurements in the range of 0.1-500 MPa. Pressure jumps can be performed as quickly as 5 ms, both with increasing and decreasing pressures. Pressure is generated by a motorized high pressure pump, and the system is controlled remotely via a graphical user interface to allow operation by a broad user base, many of whom may have little previous experience of high pressure technology. Samples are loaded through a dedicated port allowing the x-ray windows to remain in place throughout an experiment; this facilitates accurate subtraction of background scattering. The system has been designed specifically for use at beamline I22 at the Diamond Light Source, United Kingdom, and has been fully integrated with the I22 beamline control systems.

  18. Scattering from fractals

    SciTech Connect (OSTI)

    Hurd, A.J.

    1989-01-01T23:59:59.000Z

    The realization that structures in Nature often can be described by Mandelbrot's ''fractals'' has led to a revolution in many areas of physics. The interaction of waves with fractal systems has, understandably, become intensely studied since scattering is the method of choice to probe delicate fractal structures such as chainlike particle aggregates. Not all of these waves are electromagnetic: neutron scattering, for example, is an important complementary tool to structural studies by x-ray and light scattering. Since the phenomenology of small-angle neutron scattering (SANS), as it is applied to fractal systems, is identical to that of small-angle x-ray scattering (SAXS), it falls within the scope of this Working Paper. 9 refs.

  19. X-ray radiography for container inspection

    DOE Patents [OSTI]

    Katz, Jonathan I. (Clayton, MO); Morris, Christopher L. (Los Alamos, NM)

    2011-06-07T23:59:59.000Z

    Arrangements of X-ray inspection systems are described for inspecting high-z materials in voluminous objects such as containers. Inspection methods may involve generating a radiographic image based on detected attenuation corresponding to a pulsed beams of radiation transmitted through a voluminous object. The pulsed beams of radiation are generated by a high-energy source and transmitted substantially downward along an incident angle, of approximately 1.degree. to 30.degree., to a vertical axis extending through the voluminous object. The generated radiographic image may be analyzed to detect on localized high attenuation representative of high-z materials and to discriminate high-z materials from lower and intermediate-z materials on the basis of the high density and greater attenuation of high-z material for higher energy (3-10 MeV) X-rays, and the compact nature of threatening masses of fissionable materials.

  20. Self-detection of x-ray Fresnel transmittivity using photoelectron-induced gas ionization

    E-Print Network [OSTI]

    Stoupin, Stanislav

    2015-01-01T23:59:59.000Z

    Electric response of an x-ray mirror enclosed in a gas flow ionization chamber was studied under the conditions of total external reflection for hard x-rays. It is shown that the electric response of the system as a function of the incidence angle is defined by x-ray Fresnel transmittivity and photon-electron attenuation properties of the mirror material. A simple interpretation of quantum yield of the system is presented. The approach provides non-invasive in-situ diagnostics of hard x-ray optics, easy access to complementary x-ray transmittivity data in x-ray reflectivity experiments and can also pave the way to novel schemes for angle and energy resolving x-ray detectors.

  1. Measuring the Running of the Electromagnetic Coupling Alpha in Small Angle Bhabha Scattering

    E-Print Network [OSTI]

    Luca Trentadue

    2006-08-07T23:59:59.000Z

    We propose a method to determine the running of $\\alpha_{QED}$ from the measurement of small-angle Bhabha scattering. The method is suited to high statistics experiments at $e^{+} e^{-}$ colliders, which are equipped with luminometers in the appropriate angular region. We present a new simulation code predicting small-angle Bhabha scattering. A detailed description of this idea can be found in A.B. Arbuzov, D. Haidt, C. Matteuzzi, M. Paganoni and L. Trentadue, The running of the electromagnetic coupling alpha in small-angle Bhabha scattering, Eur. Phys. J. C34, 267 (2004).

  2. Small angle neutron scattering study of deuterated sodium dodecylsulfate micellization in dilute poly((2edimethylamino)ethyl methacrylate) solutions

    E-Print Network [OSTI]

    Kofinas, Peter

    Small angle neutron scattering study of deuterated sodium dodecylsulfate micellization in dilute 2010 Keywords: Poly((2edimethylamino)ethyl methacrylate) Micelle Small angle neutron scattering a b angle neutron scattering. We found three transitions of the poly ((2edimethylamino)ethyl methacrylate

  3. Static light scattering and small-angle neutron scattering study on aggregated recombinant gelatin in aqueous solution

    E-Print Network [OSTI]

    Sutter, Marc

    2006-10-25T23:59:59.000Z

    Static Light Scattering and Small-Angle Neutron Scattering Study on Aggregated Recombinant Gelatin in Aqueous Solution A. Ramzi 1, M. Sutter 2, W.E. Hennink 1, W. Jiskoot 1,2 1 Department of Pharmaceutics, UIPS, Utrecht University, The Netherlands...-angle neutron scattering (SANS) for detecting aggregation of recombinant gelatin in aqueous solution and to obtain structural information about the aggregates. Recombinant Gelatin: RG-15-His 5.6Ser 25.2Pro 1.9Lys 3.7His 34.2Gly 15.5Gln 5.2Glu 11.8Asn 1.2Ala...

  4. Calibration procedures for charge-coupled device x-ray detectors S. L. Barnaa)

    E-Print Network [OSTI]

    Gruner, Sol M.

    Calibration procedures for charge-coupled device x-ray detectors S. L. Barnaa) Department for publication 29 March 1999 Calibration procedures are described for use with electronic x-ray detectors variations for both small-angle and wide-angle applications. The accuracy of the calibration procedures

  5. Investigation of microstructure of disordered colloidal systems by small-angle scattering

    E-Print Network [OSTI]

    Chiang, Wei-Shan

    2014-01-01T23:59:59.000Z

    Small-angle scattering (SAS) has been widely applied to study the microstructure of colloidal systems. Although colloids cover a wide range of materials, in general they can simply be viewed as basic building particles ...

  6. Demonstration of a novel focusing small-angle neutron scattering instrument equipped with axisymmetric mirrors

    E-Print Network [OSTI]

    Liu, Dazhi

    Small-angle neutron scattering (SANS) is the most significant neutron technique in terms of impact on science and engineering. However, the basic design of SANS facilities has not changed since the technique’s inception ...

  7. SU-E-I-67: X-Ray Fluorescence for Energy Response Calibration of a Photon Counting Detector: A Simulation Study

    SciTech Connect (OSTI)

    Cho, H; Ding, H; Ziemer, B; Molloi, S [University of California, Irvine, CA (United States)

    2014-06-01T23:59:59.000Z

    Purpose: To investigate the feasibility of energy calibration and energy response characterization of a photon counting detector using x-ray fluorescence. Methods: A comprehensive Monte Carlo simulation study was done to investigate the influence of various geometric components on the x-ray fluorescence measurement. Different materials, sizes, and detection angles were simulated using Geant4 Application for Tomographic Emission (GATE) Monte Carlo package. Simulations were conducted using 100 kVp tungsten-anode spectra with 2 mm Al filter for a single pixel cadmium telluride (CdTe) detector with 3 × 3 mm2 in detection area. The fluorescence material was placed 300 mm away from both the x-ray source and the detector. For angular dependence measurement, the distance was decreased to 30 mm to reduce the simulation time. Compound materials, containing silver, barium, gadolinium, hafnium, and gold in cylindrical shape, were simulated. The object size varied from 5 to 100 mm in diameter. The angular dependence of fluorescence and scatter were simulated from 20° to 170° with an incremental step of 10° to optimize the fluorescence to scatter ratio. Furthermore, the angular dependence was also experimentally measured using a spectrometer (X-123CdTe, Amptek Inc., MA) to validate the simulation results. Results: The detection angle between 120° to 160° resulted in more optimal x-ray fluorescence to scatter ratio. At a detection angle of 120°, the object size did not have a significant effect on the fluorescence to scatter ratio. The experimental results of fluorescence angular dependence are in good agreement with the simulation results. The K? and K? peaks of five materials could be identified. Conclusion: The simulation results show that the x-ray fluorescence procedure has the potential to be used for detector energy calibration and detector response characteristics by using the optimal system geometry.

  8. X-ray microscope assemblies. Final report and metrology report

    SciTech Connect (OSTI)

    Zehnpfennig, T.F.

    1981-04-13T23:59:59.000Z

    This is the Final Report and Metrology Report prepared under Lawrence Livermore Laboratory Subcontract 9936205, X-ray Microscope Assemblies. The purpose of this program was to design, fabricate, and perform detailed metrology on an axisymmetric grazing-incidence x-ray microscope (XRMS) to be used as a diagnostic instrument in the Lawrence Livermore Laser Fusion Program. The optical configuration chosen for this device consists of two internally polished surfaces of revolution: an hyperboloid facing the object; and a confocal, co-axial elliposid facing the image. This arrangement is known as the Wolter Type-I configuration. The grazing angle of reflection for both surfaces is approximately 1/sup 0/. The general optical performance goals under this program were to achieve a spatial resolution in the object plane in the soft x-ray region of approximately 1 micron, and to achieve an effective solid collecting angle which is an appreciable fraction of the geometric solid collecting angle.

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

    SciTech Connect (OSTI)

    Guo, J.-H.

    2005-07-30T23:59:59.000Z

    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.

  10. angle elastic scattering: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    hadronic (piN) states. An estimate of the beam-normal single-spin asymmetry for the scattering from the neutron is made using a quasi-static deuterium approximation, and is...

  11. Miniature x-ray source

    DOE Patents [OSTI]

    Trebes, James E. (Livermore, CA); Bell, Perry M. (Tracy, CA); Robinson, Ronald B. (Modesto, CA)

    2000-01-01T23:59:59.000Z

    A miniature x-ray source utilizing a hot filament cathode. The source has a millimeter scale size and is capable of producing broad spectrum x-ray emission over a wide range of x-ray energies. The miniature source consists of a compact vacuum tube assembly containing the hot filament cathode, an anode, a high voltage feedthru for delivering high voltage to the cathode, a getter for maintaining high vacuum, a connector for initial vacuum pump down and crimp-off, and a high voltage connection for attaching a compact high voltage cable to the high voltage feedthru. At least a portion of the vacuum tube wall is fabricated from highly x-ray transparent materials, such as sapphire, diamond, or boron nitride.

  12. A high pressure cell for supercritical CO{sub 2} on-line chemical reactions studied with x-ray techniques

    SciTech Connect (OSTI)

    Hermida-Merino, Daniel; Portale, Giuseppe; Bras, Wim, E-mail: Wim.Bras@esrf.eu, E-mail: Steve.Howdle@nottingham.ac.uk [DUBBLE@ESRF, Netherlands Organisation for Scientific Research (N.W.O.), CS40220, 38043, Grenoble, Cedex 9 (France); Fields, Peter; Wilson, Richard; Bassett, Simon P.; Jennings, James; Dellar, Martin; Howdle, Steven M., E-mail: Wim.Bras@esrf.eu, E-mail: Steve.Howdle@nottingham.ac.uk [School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD (United Kingdom); Gommes, Cedric [Department of Chemical Engineering, University of Liège B6A, allée du 6 Août 3, B-4000 Liège (Belgium); Vrolijk, Benno C. M. [Element Six BV, P.O. Box 119, 5430 AC Cuijk (Netherlands)

    2014-09-15T23:59:59.000Z

    A versatile high pressure X-ray sample cell has been developed for conducting in situ time-resolved X-ray scattering experiments in the pressure and temperature regime required (pressures up to 210 bars and temperatures up to 120 °C) for chemical reactions in supercritical fluids. The large exit opening angle of the cell allows simultaneous performance of SAXS-WAXS experiments. Diamond windows are used in order to benefit from the combination of maximum strength, minimal X-ray absorption and chemical inertia. The sample cell can also be utilised for X-ray spectroscopy experiments over a wide range of photon energies. Results of the online synthesis of a block copolymer, poly(methyl methacrylate-block-poly(benzyl methacrylate), by Reversible Addition-Fragmentation Chain Transfer (RAFT) in a supercritical CO{sub 2} dispersion polymerisation will be discussed. The contribution of the density fluctuations, as function of temperature, to the X-ray scattering signal has been quantified in order to allow appropriate background subtractions.

  13. X-Ray Emission from Jupiter, Saturn, and Earth: A Short Review

    E-Print Network [OSTI]

    Anil Bhardwaj

    2006-05-11T23:59:59.000Z

    Jupiter, Saturn, and Earth - the three planets having dense atmosphere and a well developed magnetosphere - are known to emit X-rays. Recently, Chandra X-ray Observatory has observed X-rays from these planets, and XMM-Newton has observed them from Jupiter and Saturn. These observations have provided improved morphological, temporal, and spectral characteristics of X-rays from these planets. Both auroral and non-auroral (low-latitude) 'disk' X-ray emissions have been observed on Earth and Jupiter. X-rays have been detected from Saturn's disk, but no convincing evidence for X-ray aurora on Saturn has been observed. The non-auroral disk X-ray emissions from Jupiter, Saturn, and Earth, are mostly produced due to scattering of solar X-rays. X-ray aurora on Earth is mainly generated via bremsstrahlung from precipitating electrons and on Jupiter via charge exchange of highlyionized energetic heavy ions precipitating into the polar atmosphere. Recent unpublished work suggests that at higher (>2 keV) energies electron bremsstrahlung also plays a role in Jupiter's X-ray aurora. This paper summarizes the recent results of X-ray observations on Jupiter, Saturn, and Earth mainly in the soft energy (~0.1-2.0 keV) band and provides a comparative overview.

  14. In-situ high-energy x-ray diffuse-scattering study of the phase transition in a Ni{sub 2}MnGa ferromagnetic shape-memory crystal.

    SciTech Connect (OSTI)

    Wang, G.; Yan-Dong, W.; Yang, R.; Yan-Dong, L.; Peter, L. K.; X-Ray Science Division; Northeastern Univ.; Univ. of Tennessee

    2008-12-01T23:59:59.000Z

    The full information on the changes in many crystallographic aspects, including the structural and microstructural characterizations, during the phase transformation is essential for understanding the phase transition and 'memory' behavior in the ferromagnetic shape-memory alloys. In the present article, the defects-related microstructural features connected to the premartensitic and martensitic transition of a Ni{sub 2}MnGa single crystal under a uniaxial pressure of 50 MPa applied along the [110] crystallographic direction were studied by the in-situ high-energy X-ray diffuse-scattering experiments. The analysis of the characteristics of diffuse-scattering patterns around different sharp Bragg spots suggests that the influences of some defect clusters on the pressure-induced phase-transition sequences of Ni2MnGa are significant. Our experiments show that an intermediate phase is produced during the premartensitic transition in the Ni{sub 2}MnGa single crystal, which is favorable for the nucleation of a martensitic phase. The compression stress along the [110] direction of the Heusler phase can promote the premartensitic and martensitic transition of the Ni{sub 2}MnGa single crystal.

  15. Chemical and displacement atomic pair correlations in crystalline solid solutions recovered by anomalous x-ray scattering in Fe-Ni alloys

    SciTech Connect (OSTI)

    Ice, G.E.; Sparks, C.J. [Oak Ridge National Lab., TN (United States); Shaffer, L.B. [Anderson Univ., Anderson, IN (United States). Dept. of Physics

    1992-12-31T23:59:59.000Z

    Short-range pair correlations of atoms in crystalline solid solutions consist of both chemical and displacement correlations. Measurement of these pair correlations is fundamental to understanding the properties of solid solutions. We discuss anomalous scattering techniques which have provided an important advance in our ability to recover these pair correlations and to model the local atomic arrangements in crystalline solid solutions of Fe-Ni alloys.

  16. Cosmic Ray Pitch Angle Scattering Through 90 o

    E-Print Network [OSTI]

    anisotropy and the amplitude of hydro­magnetic waves gener­ ated by this streaming instability is limited rise to the dominant form of wave dissipation). We also account for ion­cyclotron damping of small wave the quasi­linear scattering with the adiabatic mir­ roring in a small boundary layer in momentum space close

  17. Elastic nucleon scattering at small angles at LHC energies

    E-Print Network [OSTI]

    S. V. Goloskokov; S. P. Kuleshov; O. V. Selyugin

    1997-07-02T23:59:59.000Z

    Predictions of the elastic proton-proton cross sections at energies of LHC are calculate on the base of the high energy dynamical model. The growth of $ds/dt$ at fixed transfer momenta are shown. The form of eikonal of elastic hadron scattering at super high energies is discussed.

  18. Linear accelerator x-ray sources with high duty cycle

    SciTech Connect (OSTI)

    Condron, Cathie; Brown, Craig; Gozani, Tsahi; Langeveld, Willem G. J. [Rapiscan Laboratories, Inc., 520 Almanor Ave. Sunnyvale, CA 94085 (United States); Hernandez, Michael [XScell corp., 2134 Old Middlefield Way, Mountain View, CA 94043 (United States)

    2013-04-19T23:59:59.000Z

    X-ray cargo inspection systems typically use a several-MV pulsed linear accelerator (linac) to produce a bremsstrahlung spectrum of x rays by bombarding a target with electrons. The x rays traverse the cargo and are detected by a detector array. Spectroscopy of the detected x rays is very desirable: if one can determine the spectrum of the transmitted x rays, one can determine the Z of the material they traversed. Even in relatively low-dose modes of operation, thousands of x rays arrive at each detector element during each pulse, unless the x rays are heavily absorbed or scattered by the cargo. For portal or fixed-site systems, dose rates, and therefore x-ray count rates, are even higher. Because of the high x-ray count rate, spectroscopy is impractical in conventional cargo inspection systems, except in certain special cases. For a mobile system, typical pulse durations are a few microseconds, and the number of pulses is on the order of 100 per second, leading to a duty factor of about 0.04%. Clearly, a linear accelerator x-ray source with much higher duty factor would be useful, since then the same number of x rays could be spread out over time, reducing the x-ray count rate. In this paper, we explore the possibility of designing a linear accelerator system, using more or less Conventional Off the Shelf (COTS) components, capable of duty cycles of 1% or greater. A survey was conducted of available linac RF source options and, given the possibilities, calculations were performed for suitable beam centerline designs. Keeping in mind that the size and cost of the accelerator system should be practical for use in a mobile cargo inspection system, only a few options are shown to be reasonably feasible, both requiring the use of klystrons instead of the magnetrons used in conventional systems. An S-Band design appears clearly possible, and there is also a promising X-Band design.

  19. Reciprocal space mapping of epitaxial materials using position-sensitive x-ray detection

    SciTech Connect (OSTI)

    Lee, S.R.; Doyle, B.L.; Drummond, T.J.; Medernach, J.W.; Schneider, R.P. Jr.

    1994-10-01T23:59:59.000Z

    Reciprocal space mapping can be efficiently carried out using a position-sensitive x-ray detector (PSD) coupled to a traditional double-axis diffractometer. The PSD offers parallel measurement of the total scattering angle of all diffracted x-rays during a single rocking-curve scan. As a result, a two-dimensional reciprocal space map can be made in a very short time similar to that of a one-dimensional rocking-curve scan. Fast, efficient reciprocal space mapping offers numerous routine advantages to the x-ray diffraction analyst. Some of these advantages are the explicit differentiation of lattice strain from crystal orientation effects in strain-relaxed heteroepitaxial layers; the nondestructive characterization of the size, shape and orientation of nanocrystalline domains in ordered-alloy epilayers; and the ability to measure the average size and shape of voids in porous epilayers. Here, the PSD-based diffractometer is described, and specific examples clearly illustrating the advantages of complete reciprocal space analysis are presented.

  20. Apparatus for the investigation of liquid systems in a shear gradient by small angle neutron scattering (SANS)

    E-Print Network [OSTI]

    Boyer, Edmond

    of small angle neutron scattering from fluids in a constant shear gradient. Typical systems which can angle neutron scattering experiments with liquids have given information about structural pro- perties759 Apparatus for the investigation of liquid systems in a shear gradient by small angle neutron

  1. X-ray absorption in distant type II QSOs

    E-Print Network [OSTI]

    Krumpe, M; Corral, A; Schwope, A D; Carrera, F J; Barcons, X; Page, M; Mateos, S; Tedds, J A; Watson, M G

    2008-01-01T23:59:59.000Z

    We present the results of the X-ray spectral analysis of an XMM-Newton-selected type II QSO sample with z>0.5 and 0.5-10 keV flux of 0.3-33 x 10^{-14} erg/s/cm^2. The distribution of absorbing column densities in type II QSOs is investigated and the dependence of absorption on X-ray luminosity and redshift is studied. We inspected 51 spectroscopically classified type II QSO candidates from the XMM-Newton Marano field survey, the XMM-Newton-2dF wide angle survey (XWAS), and the AXIS survey to set-up a well-defined sample with secure optical type II identifications. Fourteen type II QSOs were classified and an X-ray spectral analysis performed. Since most of our sources have only ~40 X-ray counts (PN-detector), we carefully studied the fit results of the simulated X-ray spectra as a function of fit statistic and binning method. We determined that fitting the spectra with the Cash-statistic and a binning of minimum one count per bin recovers the input values of the simulated X-ray spectra best. Above 100 PN coun...

  2. Salt-Dependent DNA Superhelix Diameter Studied by Small Angle Neutron Scattering Measurements and Monte Carlo Simulations

    E-Print Network [OSTI]

    Langowski, Jörg

    Salt-Dependent DNA Superhelix Diameter Studied by Small Angle Neutron Scattering Measurements-38042 Grenoble Cedex 9, France ABSTRACT Using small angle neutron scattering we have measured the static the same behavior between 10 and 100 mM salt concentration: An undulation in the scattering curve

  3. Compact x-ray source and panel

    DOE Patents [OSTI]

    Sampayon, Stephen E. (Manteca, CA)

    2008-02-12T23:59:59.000Z

    A compact, self-contained x-ray source, and a compact x-ray source panel having a plurality of such x-ray sources arranged in a preferably broad-area pixelized array. Each x-ray source includes an electron source for producing an electron beam, an x-ray conversion target, and a multilayer insulator separating the electron source and the x-ray conversion target from each other. The multi-layer insulator preferably has a cylindrical configuration with a plurality of alternating insulator and conductor layers surrounding an acceleration channel leading from the electron source to the x-ray conversion target. A power source is connected to each x-ray source of the array to produce an accelerating gradient between the electron source and x-ray conversion target in any one or more of the x-ray sources independent of other x-ray sources in the array, so as to accelerate an electron beam towards the x-ray conversion target. The multilayer insulator enables relatively short separation distances between the electron source and the x-ray conversion target so that a thin panel is possible for compactness. This is due to the ability of the plurality of alternating insulator and conductor layers of the multilayer insulators to resist surface flashover when sufficiently high acceleration energies necessary for x-ray generation are supplied by the power source to the x-ray sources.

  4. Chandra Multiwavelength Project X-ray Point Source Catalog

    E-Print Network [OSTI]

    Minsun Kim; Dong-Woo Kim; Belinda J. Wilkes; Paul J. Green; Eunhyeuk Kim; Craig S. Anderson; Wayne A. Barkhouse; Nancy R. Evans; Zeljko Ivezic; Margarita Karovska; Vinay L. Kashyap; Myung Gyoon Lee; Peter Maksym; Amy E. Mossman; John D. Silverman; Harvey D. Tananbaum

    2006-11-28T23:59:59.000Z

    We present the Chandra Multiwavelength Project (ChaMP) X-ray point source catalog with ~6,800 X-ray sources detected in 149 Chandra observations covering \\~10 deg^2. The full ChaMP catalog sample is seven times larger than the initial published ChaMP catalog. The exposure time of the fields in our sample ranges from 0.9 to 124 ksec, corresponding to a deepest X-ray flux limit of f_{0.5-8.0} = 9 x 10^{-16} erg/cm2/sec. The ChaMP X-ray data have been uniformly reduced and analyzed with ChaMP-specific pipelines, and then carefully validated by visual inspection. The ChaMP catalog includes X-ray photometric data in 8 different energy bands as well as X-ray spectral hardness ratios and colors. To best utilize the ChaMP catalog, we also present the source reliability, detection probability and positional uncertainty. To quantitatively assess those parameters, we performed extensive simulations. In particular, we present a set of empirical equations: the flux limit as a function of effective exposure time, and the positional uncertainty as a function of source counts and off axis angle. The false source detection rate is ~1% of all detected ChaMP sources, while the detection probability is better than ~95% for sources with counts >30 and off axis angle <5 arcmin. The typical positional offset between ChaMP X-ray source and their SDSS optical counterparts is 0.7+-0.4 arcsec, derived from ~900 matched sources.

  5. From Nuclei to Micro-structure: investigating intermediate length scales by small angle laser light scattering

    E-Print Network [OSTI]

    Richard Beyer; Markus Franke; Hans Joachim Schöpe; Eckhard Bartsch; Thomas Palberg

    2014-12-02T23:59:59.000Z

    Hard spheres are a well recognized model system of statistical physics and soft condensed matter. Their crystallization behaviour has been intensively studied at the structural length scale by Bragg light scattering and/or high resolution microscopy. We here present an improved light scattering apparatus capable to perform simultaneous measurements in the Bragg scattering regime and in the small angle regime. We give an account of its construction and demonstrate its performance for several examples of hard sphere and attractive hard sphere suspensions. Comparison of small angle to Bragg data allows a calibration of the sequence of events in time. We show how important complementary information can be gained from the small angle studies e.g. on the immediate environment of the growing crystals or the global scale crystallite distribution. We further demonstrate that processes occurring on larger length scales have a significant influence on the crystallization kinetics and the final micro-structure.

  6. The new very small angle neutron scattering spectrometer at Laboratoire Leon Brillouin

    E-Print Network [OSTI]

    Sylvain Desert; Vincent Thevenot; Julian Oberdisse; Annie Brulet

    2007-06-12T23:59:59.000Z

    The design and characteristics of the new very small angle neutron scattering spectrometer under construction at the Laboratoire Leon Brillouin is described. Its goal is to extend the range of scattering vectors magnitudes towards 2x10{-4} /A. The unique feature of this new spectrometer is a high resolution two dimensional image plate detector sensitive to neutrons. The wavelength selection is achieved by a double reflection supermirror monochromator and the collimator uses a novel multibeam design.

  7. Focused X-ray source

    DOE Patents [OSTI]

    Piestrup, M.A.; Boyers, D.G.; Pincus, C.I.; Maccagno, P.

    1990-08-21T23:59:59.000Z

    Disclosed is an intense, relatively inexpensive X-ray source (as compared to a synchrotron emitter) for technological, scientific, and spectroscopic purposes. A conical radiation pattern produced by a single foil or stack of foils is focused by optics to increase the intensity of the radiation at a distance from the conical radiator. 8 figs.

  8. X-ray characterization of solid small molecule organic materials

    SciTech Connect (OSTI)

    Billinge, Simon; Shankland, Kenneth; Shankland, Norman; Florence, Alastair

    2014-06-10T23:59:59.000Z

    The present invention provides, inter alia, methods of characterizing a small molecule organic material, e.g., a drug or a drug product. This method includes subjecting the solid small molecule organic material to x-ray total scattering analysis at a short wavelength, collecting data generated thereby, and mathematically transforming the data to provide a refined set of data.

  9. Stratigraphic correlation with X-ray powder patterns

    E-Print Network [OSTI]

    Singletary, John B

    1951-01-01T23:59:59.000Z

    pattern of maxima characteristic of all the principal spacings. For instance, if the radiation detector is set so as to observe the secondary diffracted beam at an angle which satisfies Bragg~s Law for some value of d found in the crystal, then a... focusing x-ray spectrometer manufac- tured by the North American Philips Company for commercial use. This instrument, shown in Fig. RB, consists of an x-ray generating unit, a goniometer, and a Geiger counter radiation detector. The patte ns were...

  10. Scanning angle Raman spectroscopy: Investigation of Raman scatter enhancement techniques for chemical analysis

    SciTech Connect (OSTI)

    Meyer, Matthew W. [Ames Laboratory

    2013-03-14T23:59:59.000Z

    This thesis outlines advancements in Raman scatter enhancement techniques by applying evanescent fields, standing-waves (waveguides) and surface enhancements to increase the generated mean square electric field, which is directly related to the intensity of Raman scattering. These techniques are accomplished by employing scanning angle Raman spectroscopy and surface enhanced Raman spectroscopy. A 1064 nm multichannel Raman spectrometer is discussed for chemical analysis of lignin. Extending dispersive multichannel Raman spectroscopy to 1064 nm reduces the fluorescence interference that can mask the weaker Raman scattering. Overall, these techniques help address the major obstacles in Raman spectroscopy for chemical analysis, which include the inherently weak Raman cross section and susceptibility to fluorescence interference.

  11. Accuracy evaluation of a Compton X-ray spectrometer with bremsstrahlung X-rays generated by a 6 MeV electron bunch

    SciTech Connect (OSTI)

    Kojima, Sadaoki, E-mail: kojima-s@ile.osaka-u.ac.jp; Arikawa, Yasunobu; Zhang, Zhe; Ikenouchi, Takahito; Morace, Alessio; Nagai, Takahiro; Abe, Yuki; Sakata, Shouhei; Inoue, Hiroaki; Utsugi, Masaru; Nakai, Mitsuo; Nishimura, Hiroaki; Shiraga, Hiroyuki; Fujioka, Shinsuke; Azechi, Hiroshi [Institute of Laser Engineering, Osaka University, 2-6 Yamada-oka, Suita, Osaka 565-0871 (Japan); Nishimura, Yasuhiko; Togawa, Hiromi [Toyota Technical Development Corporation, 1-21 Imae, Hanamoto-cho, Toyota, Aichi 470-0334 (Japan); Ozaki, Tetsuo [National Institute for Fusion Science, 322-6 Oroshicho, Toki, Gifu 509-5292 (Japan); Kato, Ryukou [The Institute of Science and Industrial Research, Osaka University, 2-6 Yamada-oka, Suita, Osaka (Japan)

    2014-11-15T23:59:59.000Z

    A Compton-scattering-based X-ray spectrometer is developed to obtain the energy distribution of fast electrons produced by intense laser and matter interactions. Bremsstrahlung X-rays generated by fast electrons in a material are used to measure fast electrons’ energy distribution in matter. In the Compton X-ray spectrometer, X-rays are converted into recoil electrons by Compton scattering in a converter made from fused silica glass, and a magnet-based electron energy analyzer is used to measure the energy distribution of the electrons that recoil in the direction of the incident X-rays. The spectrum of the incident X-rays is reconstructed from the energy distribution of the recoil electrons. The accuracy of this spectrometer is evaluated using a quasi-monoenergetic 6 MeV electron bunch that emanates from a linear accelerator. An electron bunch is injected into a 1.5 mm thick tungsten plate to produce bremsstrahlung X-rays. The spectrum of these bremsstrahlung X-rays is obtained in the range from 1 to 9 MeV. The energy of the electrons in the bunch is estimated using a Monte Carlo simulation of particle-matter interactions. The result shows that the spectrometer's energy accuracy is ±0.5 MeV for 6.0 MeV electrons.

  12. X-ray emission from Saturn

    E-Print Network [OSTI]

    Ness, J U; Wolk, S J; Dennerl, K; Burwitz, V

    2004-01-01T23:59:59.000Z

    We report the first unambiguous detection of X-ray emission originating from Saturn with a Chandra observation, duration 65.5 ksec with ACIS-S3. Beyond the pure detection we analyze the spatial distribution of X-rays on the planetary surface, the light curve, and some spectral properties. The detection is based on 162 cts extracted from the ACIS-S3 chip within the optical disk of Saturn. We found no evidence for smaller or larger angular extent. The expected background level is 56 cts, i.e., the count rate is (1.6 +- 0.2) 10^-3 cts/s. The extracted photons are rather concentrated towards the equator of the apparent disk, while both polar caps have a relative photon deficit. The inclination angle of Saturn during the observation was -27 degrees, so that the northern hemisphere was not visible during the complete observation. In addition, it was occulted by the ring system. We found a small but significant photon excess at one edge of the ring system. The light curve shows a small dip twice at identical phases,...

  13. Solution-Based Structural Analysis of the Decaheme Cytochrome, MtrA, by Small-Angle X-ray Scattering and Analytical Ultracentrifugation

    E-Print Network [OSTI]

    Firer-Sherwood, Mackenzie A.

    The potential exploitation of metal-reducing bacteria as a means for environmental cleanup or alternative fuel is an exciting prospect; however, the cellular processes that would allow for these applications need to be ...

  14. X-ray absorption in distant type II QSOs

    E-Print Network [OSTI]

    M. Krumpe; G. Lamer; A. Corral; A. D. Schwope; F. J. Carrera; X. Barcons; M. Page; S. Mateos; J. A. Tedds; M. G. Watson

    2008-03-10T23:59:59.000Z

    We present the results of the X-ray spectral analysis of an XMM-Newton-selected type II QSO sample with z>0.5 and 0.5-10 keV flux of 0.3-33 x 10^{-14} erg/s/cm^2. The distribution of absorbing column densities in type II QSOs is investigated and the dependence of absorption on X-ray luminosity and redshift is studied. We inspected 51 spectroscopically classified type II QSO candidates from the XMM-Newton Marano field survey, the XMM-Newton-2dF wide angle survey (XWAS), and the AXIS survey to set-up a well-defined sample with secure optical type II identifications. Fourteen type II QSOs were classified and an X-ray spectral analysis performed. Since most of our sources have only ~40 X-ray counts (PN-detector), we carefully studied the fit results of the simulated X-ray spectra as a function of fit statistic and binning method. We determined that fitting the spectra with the Cash-statistic and a binning of minimum one count per bin recovers the input values of the simulated X-ray spectra best. Above 100 PN counts, the free fits of the spectrum's slope and absorbing hydrogen column density are reliable. We find only moderate absorption (N_H=(2-10) x 10^22 cm^-2) and no obvious trends with redshift and intrinsic X-ray luminosity. In a few cases a Compton-thick absorber cannot be excluded. Two type II objects with no X-ray absorption were discovered. We find no evidence for an intrinsic separation between type II AGN and high X-ray luminosity type II QSO in terms of absorption. The stacked X-ray spectrum of our 14 type II QSOs shows no iron K-alpha line. In contrast, the stack of the 8 type II AGN reveals a very prominent iron K-alpha line at an energy of ~ 6.6 keV and an EW ~ 2 keV.

  15. Dual-angle, self-calibrating Thomson scattering measurements in RFX-MOD

    SciTech Connect (OSTI)

    Giudicotti, L., E-mail: leonardo.giudicotti@unipd.it [Consorzio RFX, Corso Stati Uniti, 4, 35127 Padova (Italy); Department of Industrial Engineering, Padova University, Via Gradenigo 6/a, 35131 Padova (Italy); Pasqualotto, R. [Department of Industrial Engineering, Padova University, Via Gradenigo 6/a, 35131 Padova (Italy); Fassina, A. [Consorzio RFX, Corso Stati Uniti, 4, 35127 Padova (Italy)

    2014-11-15T23:59:59.000Z

    In the multipoint Thomson scattering (TS) system of the RFX-MOD experiment the signals from a few spatial positions can be observed simultaneously under two different scattering angles. In addition the detection system uses optical multiplexing by signal delays in fiber optic cables of different length so that the two sets of TS signals can be observed by the same polychromator. Owing to the dependence of the TS spectrum on the scattering angle, it was then possible to implement self-calibrating TS measurements in which the electron temperature T{sub e}, the electron density n{sub e} and the relative calibration coefficients of spectral channels sensitivity C{sub i} were simultaneously determined by a suitable analysis of the two sets of TS data collected at the two angles. The analysis has shown that, in spite of the small difference in the spectra obtained at the two angles, reliable values of the relative calibration coefficients can be determined by the analysis of good S/N dual?angle spectra recorded in a few tens of plasma shots. This analysis suggests that in RFX-MOD the calibration of the entire set of TS polychromators by means of the similar, dual-laser (Nd:YAG/Nd:YLF) TS technique, should be feasible.

  16. Portable X-Ray, K-Edge Heavy Metal Detector

    SciTech Connect (OSTI)

    Fricke, V.

    1999-10-25T23:59:59.000Z

    The X-Ray, K-Edge Heavy Metal Detection System was designed and built by Ames Laboratory and the Center for Nondestructive Evaluation at Iowa State University. The system uses a C-frame inspection head with an X-ray tube mounted on one side of the frame and an imaging unit and a high purity germanium detector on the other side. the inspection head is portable and can be easily positioned around ventilation ducts and pipes up to 36 inches in diameter. Wide angle and narrow beam X-ray shots are used to identify the type of holdup material and the amount of the contaminant. Precise assay data can be obtained within minutes of the interrogation. A profile of the containerized holdup material and a permanent record of the measurement are immediately available.

  17. The nature of the Vela X-ray "jet"

    E-Print Network [OSTI]

    V. V. Gvaramadze

    1999-12-02T23:59:59.000Z

    The nature of the Vela X-ray "jet", recently discovered by Markwardt & \\"Ogelman (1995), is examined. It is suggested that the "jet" arises along the interface of domelike deformations of the Rayleigh-Taylor unstable shell of the Vela supernova remnant; thereby the "jet" is interpreted as a part of the general shell of the remnant. The origin of deformations as well as the general structure of the remnant are discussed in the framework of a model based on a cavity explosion of a supernova star. It is suggested that the shell deformations viewed at various angles appear as filamentary structures visible throughout the Vela supernova remnant at radio, optical, and X-ray wavelengths. A possible origin of the nebula of hard X-ray emission detected by Willmore et al. (1992) around the Vela pulsar is proposed.

  18. Wide angle Compton scattering on the proton: study of power suppressed corrections

    E-Print Network [OSTI]

    Kivel, N

    2015-01-01T23:59:59.000Z

    We study the wide angle Compton scattering process on a proton within the soft collinear factorization (SCET) framework. The main purpose of this work is to estimate the effect due to certain power suppressed corrections. We consider all possible kinematical power corrections and also include the subleading amplitudes describing the scattering with nucleon helicity flip. Under certain assumptions we present a leading-order factorization formula for these amplitudes which includes the hard- and soft-spectator contributions. We apply the formalism and perform a phenomenological analysis of the cross section and asymmetries in the wide angle Compton scattering on a proton. We assume that in the relevant kinematical region where $-t,-u>2.5$~GeV$^{2}$ the dominant contribution is provided by the soft-spectator mechanism. The hard coefficient functions of the corresponding SCET operators are taken in the leading-order approximation. The analysis of existing cross section data shows that the contribution of the heli...

  19. Producing X-rays at the APS

    ScienceCinema (OSTI)

    None

    2013-04-19T23:59:59.000Z

    An introduction and overview of the Advanced Photon Source at Argonne National Laboratory, the technology that produces the brightest X-ray beams in the Western Hemisphere, and the research carried out by scientists using those X-rays.

  20. Lensless X-Ray Imaging in Reflection

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    X-Ray Imaging in Reflection Print The advent of x-ray free-electron laser (XFEL) light sources has led to an outburst of research activities in the field of lensless imaging. XFELs...

  1. APS X-rays Reveal Picasso's Secret

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    | 2003 | 2002 | 2001 2000 Subscribe to APS News rss feed APS X-rays Reveal Picasso's Secret OCTOBER 15, 2012 Bookmark and Share X-rays reveal that Picasso's "Old Guitarist," at...

  2. Spectral analysis of X-ray binaries

    E-Print Network [OSTI]

    Fridriksson, Joel Karl

    2011-01-01T23:59:59.000Z

    In this thesis, I present work from three separate research projects associated with observations of X-ray binaries. Two of those revolve around spectral characteristics of neutron star low-mass X-ray binaries (NS-LMXBs), ...

  3. X-ray Perspective of the Twisted Magnetospheres of Magnetars

    E-Print Network [OSTI]

    Weng, Shan-Shan; Guver, Tolga; Lin, Lin

    2015-01-01T23:59:59.000Z

    Anomalous X-ray pulsars (AXPs) and soft gamma-ray repeaters (SGRs) are recognized as the most promising magnetar candidates as indicated by their energetic bursts and rapid spin-downs. It is expected that the strong magnetic field leaves distinctive imprints on the emergent radiation both by affecting the radiative processes in atmospheres of magnetars and by scattering in the upper magnetospheres. We construct a self-consistent physical model that incorporates emission from the magnetar surface and its reprocessing in the three-dimensional (3D) twisted magnetosphere using a Monte Carlo technique. The synthetic spectra are characterized by four parameters: surface temperature $kT$, surface magnetic field strength $B$, magnetospheric twist angle $\\Delta\\phi$, and the normalized electron velocity $\\beta$. We also create a tabular model (STEMS3D) and apply it to a large sample of XMM-Newton spectra of magnetars. The model successfully fits nearly all spectra, and the obtained magnetic field for the 7 out of 11 s...

  4. Microgap x-ray detector

    DOE Patents [OSTI]

    Wuest, C.R.; Bionta, R.M.; Ables, E.

    1994-05-03T23:59:59.000Z

    An x-ray detector is disclosed which provides for the conversion of x-ray photons into photoelectrons and subsequent amplification of these photoelectrons through the generation of electron avalanches in a thin gas-filled region subject to a high electric potential. The detector comprises a cathode (photocathode) and an anode separated by the thin, gas-filled region. The cathode may comprise a substrate, such a beryllium, coated with a layer of high atomic number material, such as gold, while the anode can be a single conducting plane of material, such as gold, or a plane of resistive material, such as chromium/silicon monoxide, or multiple areas of conductive or resistive material, mounted on a substrate composed of glass, plastic or ceramic. The charge collected from each electron avalanche by the anode is passed through processing electronics to a point of use, such as an oscilloscope. 3 figures.

  5. Microgap x-ray detector

    DOE Patents [OSTI]

    Wuest, Craig R. (Danville, CA); Bionta, Richard M. (Livermore, CA); Ables, Elden (Livermore, CA)

    1994-01-01T23:59:59.000Z

    An x-ray detector which provides for the conversion of x-ray photons into photoelectrons and subsequent amplification of these photoelectrons through the generation of electron avalanches in a thin gas-filled region subject to a high electric potential. The detector comprises a cathode (photocathode) and an anode separated by the thin, gas-filled region. The cathode may comprise a substrate, such a beryllium, coated with a layer of high atomic number material, such as gold, while the anode can be a single conducting plane of material, such as gold, or a plane of resistive material, such as chromium/silicon monoxide, or multiple areas of conductive or resistive material, mounted on a substrate composed of glass, plastic or ceramic. The charge collected from each electron avalanche by the anode is passed through processing electronics to a point of use, such as an oscilloscope.

  6. Phase-sensitive X-ray imager

    DOE Patents [OSTI]

    Baker, Kevin Louis

    2013-01-08T23:59:59.000Z

    X-ray phase sensitive wave-front sensor techniques are detailed that are capable of measuring the entire two-dimensional x-ray electric field, both the amplitude and phase, with a single measurement. These Hartmann sensing and 2-D Shear interferometry wave-front sensors do not require a temporally coherent source and are therefore compatible with x-ray tubes and also with laser-produced or x-pinch x-ray sources.

  7. ON THE PROSPECT OF CONSTRAINING BLACK HOLE SPIN THROUGH X-RAY SPECTROSCOPY OF HOTSPOTS

    E-Print Network [OSTI]

    Yaqoob, Tahir

    Future X-ray instrumentation is expected to allow us to significantly improve the constraints derived from the Fe?K lines in active galactic nuclei, such as the black hole angular momentum (spin) and the inclination angle ...

  8. Spatial resolution of synchrotron x-ray microtomography in high energy range: Effect of x-ray energy and sample-to-detector distance

    SciTech Connect (OSTI)

    Seo, D.; Tomizato, F.; Toda, H.; Kobayashi, M. [Department of Mechanical Engineering, Toyohashi University of Technology, Toyohashi, Aichi 441-8580 (Japan); Uesugi, K.; Takeuchi, A.; Suzuki, Y. [Japan Synchrotron Radiation Research Institute, Mikazuki, Sayo, Hyogo 679-5198 (Japan)

    2012-12-24T23:59:59.000Z

    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 {mu}m 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.

  9. X-ray spectroscopy of low-mass X-ray binaries

    E-Print Network [OSTI]

    Juett, Adrienne Marie, 1976-

    2004-01-01T23:59:59.000Z

    I present high-resolution X-ray grating spectroscopy of neutron stars in low-mass X-ray binaries (LMXBs) using instruments onboard the Chandra X-ray Observatory and the X-ray Multi-Mirror Mission (XMM-Newton). The first ...

  10. Extending The Methodology Of X-ray Crystallography To Allow X-ray

    E-Print Network [OSTI]

    Miao, Jianwei "John"

    , the radiation damage. While the radiation damage problem can be mitigated somewhat by using cryogenic techniques resolution without serious radiation damage to the specimens. Although X-ray crystallography becomesExtending The Methodology Of X-ray Crystallography To Allow X-ray Microscopy Without X-ray Optics

  11. Note: Application of a pixel-array area detector to simultaneous single crystal x-ray diffraction and x-ray absorption spectroscopy measurements

    SciTech Connect (OSTI)

    Sun, Cheng-Jun, E-mail: cjsun@aps.anl.gov; Brewe, Dale L.; Heald, Steve M. [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States)] [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Zhang, Bangmin [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States) [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Department of Materials Science and Engineering, National University of Singapore, 117575 Singapore (Singapore); NUSNNI-Nanocore, National University of Singapore, 117411 Singapore (Singapore); Chen, Jing-Sheng; Chow, G. M. [Department of Materials Science and Engineering, National University of Singapore, 117575 Singapore (Singapore)] [Department of Materials Science and Engineering, National University of Singapore, 117575 Singapore (Singapore); Venkatesan, T. [NUSNNI-Nanocore, National University of Singapore, 117411 Singapore (Singapore) [NUSNNI-Nanocore, National University of Singapore, 117411 Singapore (Singapore); Department of Physics, National University of Singapore, 117542 Singapore (Singapore); Department of Electrical and Computer Engineering, National University of Singapore, 117575 Singapore (Singapore)

    2014-04-15T23:59:59.000Z

    X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS) are two main x-ray techniques in synchrotron radiation facilities. In this Note, we present an experimental setup capable of performing simultaneous XRD and XAS measurements by the application of a pixel-array area detector. For XRD, the momentum transfer in specular diffraction was measured by scanning the X-ray energy with fixed incoming and outgoing x-ray angles. By selecting a small fixed region of the detector to collect the XRD signal, the rest of the area was available for collecting the x-ray fluorescence for XAS measurements. The simultaneous measurement of XRD and X-ray absorption near edge structure for Pr{sub 0.67}Sr{sub 0.33}MnO{sub 3} film was demonstrated as a proof of principle for future time-resolved pump-probe measurements. A static sample makes it easy to maintain an accurate overlap of the X-ray spot and laser pump beam.

  12. Synchronization of x-ray pulses to the pump laser in an ultrafast x-ray facility

    E-Print Network [OSTI]

    Corlett, J.N.; Barry, W.; Byrd, J.M.; Schoenlein, R.; Zholents, A.

    2002-01-01T23:59:59.000Z

    Accurate timing of ultrafast x-ray probe pulses emitted fromOF X-RAY PULSES TO THE PUMP LASER IN AN ULTRAFAST X-RAY

  13. X-ray holography of biological specimens

    SciTech Connect (OSTI)

    Solem, J.C.

    1984-01-01T23:59:59.000Z

    The author reviews the reasons for x-ray imaging of biological specimens and the techniques presently being used for x-ray microscopy. The author points out the advantages of x-ray holography and the difficulties of obtaining the requisite coherence with conventional sources. The author discusses the problems of radiation damage and the remarkable fact that short pulse x-ray sources circumvent these problems and obtain high-resolution images of specimens in the living state. Finally, the author reviews some of the efforts underway to develop high-intensity coherent x-ray sources for the laboratory. 14 references, 5 figures, 2 tables.

  14. Soft X-ray techniques to study mesoscale magnetism

    E-Print Network [OSTI]

    Kortright, Jeffrey B.

    2003-01-01T23:59:59.000Z

    X-Ray Techniques to Study Mesoscale Magnetism Jeffrey B.X-Ray Techniques to Study Mesoscale Magnetism Jeffrey B.

  15. Techniques for synchronization of X-Ray pulses to the pump laser in an ultrafast X-Ray facility

    E-Print Network [OSTI]

    Corlett, J.N.; Doolittle, L.; Schoenlein, R.; Staples, J.; Wilcox, R.; Zholents, A.

    2003-01-01T23:59:59.000Z

    synchronization of ultrafast x-ray pulses produced in theAccurate timing of ultrafast x-ray probe pulses emitted fromOF X-RAY PULSES TO THE PUMP LASER IN AN ULTRAFAST X-RAY

  16. Controlling X-rays With Light

    SciTech Connect (OSTI)

    Glover, Ernie; Hertlein, Marcus; Southworth, Steve; Allison, Tom; van Tilborg, Jeroen; Kanter, Elliot; Krassig, B.; Varma, H.; Rude, Bruce; Santra, Robin; Belkacem, Ali; Young, Linda

    2010-08-02T23:59:59.000Z

    Ultrafast x-ray science is an exciting frontier that promises the visualization of electronic, atomic and molecular dynamics on atomic time and length scales. A largelyunexplored area of ultrafast x-ray science is the use of light to control how x-rays interact with matter. In order to extend control concepts established for long wavelengthprobes to the x-ray regime, the optical control field must drive a coherent electronic response on a timescale comparable to femtosecond core-hole lifetimes. An intense field is required to achieve this rapid response. Here an intense optical control pulse isobserved to efficiently modulate photoelectric absorption for x-rays and to create an ultrafast transparency window. We demonstrate an application of x-ray transparencyrelevant to ultrafast x-ray sources: an all-photonic temporal cross-correlation measurement of a femtosecond x-ray pulse. The ability to control x-ray/matterinteractions with light will create new opportunities at current and next-generation x-ray light sources.

  17. X-ray Observations of Mrk 231

    E-Print Network [OSTI]

    T. J. Turner

    1998-08-10T23:59:59.000Z

    This paper presents new X-ray observations of Mrk 231, an active galaxy of particular interest due to its large infrared luminosity and the presence of several blueshifted broad absorption line (BAL) systems, a phenomenon observed in a small fraction of QSOs. A ROSAT HRI image of Mrk 231 is presented, this shows an extended region of soft X-ray emission, covering several tens of kpc, consistent with the extent of the host galaxy. An ASCA observation of Mrk 231 is also presented. Hard X-rays are detected but the data show no significant variability in X-ray flux. The hard X-ray continuum is heavily attenuated and X-ray column estimates range from ~ 2 x 10^{22} - 10^{23} cm^{-2} depending on whether the material is assumed to be neutral or ionized, and on the model assumed for the extended X-ray component. These ASCA data provide only the second hard X-ray spectrum of a BAL AGN presented to date. The broad-band spectral-energy-distribution of the source is discussed. While Mrk 231 is X-ray weak compared to Seyfert 1 galaxies, it has an optical-to-X-ray spectrum typical of a QSO.

  18. Small-angle scattering instruments on a 1 MW long pulse spallation source

    SciTech Connect (OSTI)

    Olah, G.A.; Hjelm, R.P.; Seeger, P.A.

    1995-12-01T23:59:59.000Z

    Two small-angle neutron scattering instruments have been designed and optimized for installation at a 1 MW long pulse spallation source. The first of these instruments allows access to length scales in materials from 10 to 400 {angstrom}, and the second instrument from 40 to 1200 {angstrom}. Design characteristics were determined and optimization was done using the MCLIB Monte Carlo instrument simulation package. The code has been {open_quote}benchmarked{close_quote} by simulating the {open_quote}as-built{close_quote} D11 spectrometer at ILL and a performance comparison of the three instruments was made. Comparisons were made by evaluating the scattered intensity for {delta} scatterers at different Q values for various instrument configurations needed to span a Q-range of 0.0007 - 0.44 {angstrom}{sup {minus}1}.

  19. Distribution of unresolvable anisotropic microstructures revealed in visibility-contrast images using x-ray Talbot interferometry

    SciTech Connect (OSTI)

    Yashiro, Wataru; Harasse, Sebastien; Kawabata, Katsuyuki; Kuwabara, Hiroaki; Yamazaki, Takashi; Momose, Atsushi [Department of Advanced Materials Science, Graduate School of Frontier Sciences, the University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561 (Japan)

    2011-09-01T23:59:59.000Z

    X-ray Talbot interferometry has been widely used as a technique for x-ray phase imaging and tomography. We propose a method using this interferometry for mapping distribution of parameters characterizing anisotropic microstructures, which are typically of the order of {mu}m in size and cannot be resolved by the imaging system, in a sample. The method uses reduction in fringe visibility, which is caused by such unresolvable microstructures, in moire images obtained using an interferometer. We applied the method to a chloroprene rubber sponge sample, which exhibited uniaxial anisotropy of reduced visibility. We measured the dependencies of reduced visibility on both the Talbot order and the orientation of the sample and obtained maps of three parameters and their anisotropies that characterize the unresolvable anisotropic microstructures in the sample. The maps indicated that the anisotropy of the sample's visibility contrast mainly originated from the anisotropy of the microstructure elements' average size. Our method directly provides structural information on unresolvable microstructures in real space, which is only accessible through the ultra-small-angle x-ray scattering measurements in reciprocal space, and is expected to be broadly applied to material, biological, and medical sciences.

  20. Solar Hard X-ray Source Sizes in a Beam-Heated and Ionised Chromosphere

    E-Print Network [OSTI]

    O'Flannagain, A; Gallagher, P T

    2014-01-01T23:59:59.000Z

    Solar flare hard X-rays (HXRs) are produced as bremsstrahlung when an accelerated population of electrons interacts with the dense chromospheric plasma. HXR observations presented by using the Ramaty High-Energy Solar Spectroscopic Imager (RHESSI) have shown that HXR source sizes are 3-6 times more extended in height than those predicted by the standard collisional thick target model (CTTM). Several possible explanations have been put forward including the multi-threaded nature of flare loops, pitch-angle scattering, and magnetic mirroring. However, the nonuniform ionisation (NUI) structure along the path of the electron beam has not been fully explored as a solution to this problem. Ionised plasma is known to be less effective at producing nonthermal bremsstrahlung HXRs when compared to neutral plasma. If the peak HXR emission was produced in a locally ionised region within the chromosphere, the intensity of emission will be preferentially reduced around this peak, resulting in a more extended source. Due to...

  1. Real-time x-ray studies of gallium nitride nanodot formation by droplet heteroepitaxy

    SciTech Connect (OSTI)

    Wang Yiyi; Oezcan, Ahmet S.; Sanborn, Christopher; Ludwig, Karl F.; Bhattacharyya, Anirban; Chandrasekaran, Ramya; Moustakas, Theodore D.; Zhou Lin; Smith, David J. [Physics Department, Boston University, Boston, Massachusetts 02215 (United States); Department of Electrical and Computer Engineering, Boston University, Boston, Massachusetts 02215 (United States); Department of Physics, Arizona State University, Tempe, Arizona 85287, USA and School of Materials, Arizona State University, Tempe, Arizona 85287 (United States)

    2007-10-01T23:59:59.000Z

    Self-organized gallium nitride nanodots have been fabricated using droplet heteroepitaxy on c-plane sapphire by plasma-assisted molecular beam epitaxy at different substrate temperatures and Ga fluxes. Nanoscale Ga droplets were initially formed on the sapphire substrate at high temperatures by Ga deposition from an effusion cell in an ultrahigh vacuum growth chamber. Subsequently, the droplets were converted into GaN nanodots using a nitrogen plasma source. The process was monitored and controlled using real-time grazing-incidence small-angle x-ray scattering. The samples were examined postgrowth by in situ grazing incidence x-ray diffraction and reflection high-energy electron diffraction, which confirmed the epitaxial relationship between the GaN nanodots and the sapphire surface. X-ray diffraction indicated that the wurtzite phase was dominant at higher substrate temperature (710 deg. C), but a mixture of wurtzite and zinc blende phases was present at a substrate temperature of 620 deg. C. Ex situ atomic force microscopy and transmission electron microscopy analyses showed that the dot size distribution was bimodal. A thin GaN continuous layer of {approx} three monolayers thick was observed by transmission electron microscopy on the sample grown at a substrate temperature of 620 deg. C, but no such layer was observed for the substrate temperature of 710 deg. C. This suggests that there is little mobility of Ga atoms in contact with the sapphire substrate at the lower temperature so that they cannot easily diffuse to nearby droplets and instead form a thin layer covering the surface.

  2. Real-Time X-ray Studies of Gallium Nitride Nanodot Formation by Droplet Heteroepitaxy

    SciTech Connect (OSTI)

    Wang,Y.; Ozcan, A.; Sanborn, C.; Ludwig, K.; Bhattacharyya, A.; Chandrasekaran, R.; Moustakas, T.; Zhou, L.; Smith, D.

    2007-01-01T23:59:59.000Z

    Self-organized gallium nitride nanodots have been fabricated using droplet heteroepitaxy on c-plane sapphire by plasma-assisted molecular beam epitaxy at different substrate temperatures and Ga fluxes. Nanoscale Ga droplets were initially formed on the sapphire substrate at high temperatures by Ga deposition from an effusion cell in an ultrahigh vacuum growth chamber. Subsequently, the droplets were converted into GaN nanodots using a nitrogen plasma source. The process was monitored and controlled using real-time grazing-incidence small-angle x-ray scattering. The samples were examined postgrowth by in situ grazing incidence x-ray diffraction and reflection high-energy electron diffraction, which confirmed the epitaxial relationship between the GaN nanodots and the sapphire surface. X-ray diffraction indicated that the wurtzite phase was dominant at higher substrate temperature (710? C), but a mixture of wurtzite and zinc blende phases was present at a substrate temperature of 620? C. Ex situ atomic force microscopy and transmission electron microscopy analyses showed that the dot size distribution was bimodal. A thin GaN continuous layer of ? three monolayers thick was observed by transmission electron microscopy on the sample grown at a substrate temperature of 620? C, but no such layer was observed for the substrate temperature of 710? C. This suggests that there is little mobility of Ga atoms in contact with the sapphire substrate at the lower temperature so that they cannot easily diffuse to nearby droplets and instead form a thin layer covering the surface.

  3. X-ray transmissive debris shield

    DOE Patents [OSTI]

    Spielman, Rick B. (Albuquerque, NM)

    1994-01-01T23:59:59.000Z

    A composite window structure is described for transmitting x-ray radiation and for shielding radiation generated debris. In particular, separate layers of different x-ray transmissive materials are laminated together to form a high strength, x-ray transmissive debris shield which is particularly suited for use in high energy fluences. In one embodiment, the composite window comprises alternating layers of beryllium and a thermoset polymer.

  4. High speed x-ray beam chopper

    DOE Patents [OSTI]

    McPherson, Armon (Oswego, IL); Mills, Dennis M. (Naperville, IL)

    2002-01-01T23:59:59.000Z

    A fast, economical, and compact x-ray beam chopper with a small mass and a small moment of inertia whose rotation can be synchronized and phase locked to an electronic signal from an x-ray source and be monitored by a light beam is disclosed. X-ray bursts shorter than 2.5 microseconds have been produced with a jitter time of less than 3 ns.

  5. X-ray populations in galaxies

    E-Print Network [OSTI]

    G. Fabbiano

    2005-11-09T23:59:59.000Z

    Today's sensistive, high resolution Chandra X-ray observations allow the study of many populations of X-ray sources. The traditional astronomical tools of photometric diagrams and luminosity functions are now applied to these populations, and provide the means for classifying the X-ray sources and probing their evolution. While overall stellar mass drives the amount of X-ray binaries in old stellar population, the amount of sources in star-forming galaxies is related to the star formation rate. Shart-lived, luminous, high mass binaries (HNXBs) dominate these young populations.

  6. X-ray laser microscope apparatus

    DOE Patents [OSTI]

    Suckewer, Szymon (Princeton, NJ); DiCicco, Darrell S. (Plainsboro, NJ); Hirschberg, Joseph G. (Coral Gables, FL); Meixler, Lewis D. (East Windsor, NJ); Sathre, Robert (Princeton, NJ); Skinner, Charles H. (Lawrenceville, NJ)

    1990-01-01T23:59:59.000Z

    A microscope consisting of an x-ray contact microscope and an optical microscope. The optical, phase contrast, microscope is used to align a target with respect to a source of soft x-rays. The source of soft x-rays preferably comprises an x-ray laser but could comprise a synchrotron or other pulse source of x-rays. Transparent resist material is used to support the target. The optical microscope is located on the opposite side of the transparent resist material from the target and is employed to align the target with respect to the anticipated soft x-ray laser beam. After alignment with the use of the optical microscope, the target is exposed to the soft x-ray laser beam. The x-ray sensitive transparent resist material whose chemical bonds are altered by the x-ray beam passing through the target mater GOVERNMENT LICENSE RIGHTS This invention was made with government support under Contract No. De-FG02-86ER13609 awarded by the Department of Energy. The Government has certain rights in this invention.

  7. Virtual Compton scattering and neutral pion electroproduction in the resonance region up to the deep inelastic region at backward angles

    E-Print Network [OSTI]

    Zhou, Z. -L.

    We have made the first measurements of the virtual Compton scattering (VCS) process via the H(e, e'p)? exclusive reaction in the nucleon resonance region, at backward angles. Results are presented for the W-dependence at ...

  8. Wide angle Compton scattering on the proton: study of power suppressed corrections

    E-Print Network [OSTI]

    N. Kivel; M. Vanderhaeghen

    2015-04-04T23:59:59.000Z

    We study the wide angle Compton scattering process on a proton within the soft collinear factorization (SCET) framework. The main purpose of this work is to estimate the effect due to certain power suppressed corrections. We consider all possible kinematical power corrections and also include the subleading amplitudes describing the scattering with nucleon helicity flip. Under certain assumptions we present a leading-order factorization formula for these amplitudes which includes the hard- and soft-spectator contributions. We apply the formalism and perform a phenomenological analysis of the cross section and asymmetries in the wide angle Compton scattering on a proton. We assume that in the relevant kinematical region where $-t,-u>2.5$~GeV$^{2}$ the dominant contribution is provided by the soft-spectator mechanism. The hard coefficient functions of the corresponding SCET operators are taken in the leading-order approximation. The analysis of existing cross section data shows that the contribution of the helicity flip amplitudes to this observable is quite small and comparable with other expected theoretical uncertainties. We also show predictions for double polarization observables for which experimental information exists.

  9. X-ray spectroscopy of neutron star low-mass X-ray binaries

    E-Print Network [OSTI]

    Krauss, Miriam Ilana

    2007-01-01T23:59:59.000Z

    In this thesis, I present work spanning a variety of topics relating to neutron star lowmass X-ray binaries (LMXBs) and utilize spectral information from X-ray observations to further our understanding of these sources. ...

  10. Measurement of the analysing power in proton-proton elastic scattering at small angles

    E-Print Network [OSTI]

    Z. Bagdasarian; D. Chiladze; S. Dymov; A. Kacharava; G. Macharashvili; S. Barsov; R. Gebel; B. Gou; M. Hartmann; I. Keshelashvili; A. Khoukaz; P. Kulessa; A. Kulikov; A. Lehrach; N. Lomidze; B. Lorentz; R. Maier; D. Mchedlishvili; S. Merzliakov; S. Mikirtychyants; M. Nioradze; H. Ohm; M. Papenbrock; D. Prasuhn; F. Rathmann; V. Serdyuk; V. Shmakova; R. Stassen; H. Stockhorst; I. I. Strakovsky; H. Ströher; M. Tabidze; A. Täschner; S. Trusov; D. Tsirkov; Yu. Uzikov; Yu. Valdau; C. Wilkin; R. L. Workman

    2014-10-28T23:59:59.000Z

    The proton analysing power in $\\vec{p}p$ elastic scattering has been measured at small angles at COSY-ANKE at 796 MeV and five other beam energies between 1.6 and 2.4 GeV using a polarised proton beam. The asymmetries obtained by detecting the fast proton in the ANKE forward detector or the slow recoil proton in a silicon tracking telescope are completely consistent. Although the analysing power results agree well with the many published data at 796 MeV, and also with the most recent partial wave solution at this energy, the ANKE data at the higher energies lie well above the predictions of this solution at small angles. An updated phase shift analysis that uses the ANKE results together with the World data leads to a much better description of these new measurements.

  11. Mode-Locked Multichromatic X-Rays in a Seeded Free-Electron Laser for Single-Shot X-Ray Spectroscopy

    SciTech Connect (OSTI)

    Xiang, Dao; Ding, Yuantao; Raubenheimer, Tor; Wu, Juhao; /SLAC

    2012-05-10T23:59:59.000Z

    We present the promise of generating gigawatt mode-locked multichromatic x rays in a seeded free-electron laser (FEL). We show that, by using a laser to imprint periodic modulation in electron beam phase space, a single-frequency coherent seed can be amplified and further translated to a mode-locked multichromatic output in an FEL. With this configuration the FEL output consists of a train of mode-locked ultrashort pulses which span a wide frequency gap with a series of equally spaced sharp lines. These gigawatt multichromatic x rays may potentially allow one to explore the structure and dynamics of a large number of atomic states simultaneously. The feasibility of generating mode-locked x rays ranging from carbon K edge ({approx}284 eV) to copper L{sub 3} edge ({approx}931 eV) is confirmed with numerical simulation using the realistic parameters of the linac coherent light source (LCLS) and LCLS-II. We anticipate that the mode-locked multichromatic x rays in FELs may open up new opportunities in x-ray spectroscopy (i.e. resonant inelastic x-ray scattering, time-resolved scattering and spectroscopy, etc.).

  12. Running of the QED coupling in small-angle Bhabha scattering at LEP

    E-Print Network [OSTI]

    G. Abbiendi

    2005-05-18T23:59:59.000Z

    Using the OPAL detector at LEP, the running of the effective QED coupling alpha(t) is measured for space-like momentum transfer, 2 \\leq -t \\leq 6 GeV^2, from the angular distribution of small-angle Bhabha scattering. This is currently the most significant direct observation of the running of the QED coupling in a single experiment and the first clear evidence of the hadronic contribution to the running in the space-like region. Our result is in good agreement with standard evaluations of alpha(t), based on data in the time-like region.

  13. Patchy worm-like micelles: solution structure studied by small-angle neutron scattering

    E-Print Network [OSTI]

    S. Rosenfeldt; F. Luedel; C. Schulreich; T. Hellweg; A. Radulescu; J. Schmelz; H. Schmalz; L. Harnau

    2012-09-20T23:59:59.000Z

    Triblock terpolymers exhibit a rich self-organization behavior including the formation of fascinating cylindrical core-shell structures with a phase separated corona. After crystallization-induced self-assembly of polystryrene-(block)-polyethylene-(block)-poly(methyl methacrylate) triblock terpolymers (abbreviated as SEMs = Styrene-Ethylene-Methacrylates) from solution, worm-like core-shell micelles with a patchy corona of polystryrene and poly(methyl methacrylate) were observed by transmission electron microscopy. However, the solution structure is still a matter of debate. Here, we present a method to distinguish in-situ between a Janus-type (two faced) and a patchy (multiple compartments) configuration of the corona. To discriminate between both models the scattering intensity must be determined mainly by one corona compartment. Contrast variation in small-angle neutron scattering enables us to focus on one compartment of the SEMs. The results validate the existence of the patchy structure also in solution.

  14. Phased Contrast X-Ray Imaging

    ScienceCinema (OSTI)

    Erin Miller

    2012-12-31T23:59:59.000Z

    The Pacific Northwest National Laboratory is developing a range of technologies to broaden the field of explosives detection. Phased contrast X-ray imaging, which uses silicon gratings to detect distortions in the X-ray wave front, may be applicable to mail or luggage scanning for explosives; it can also be used in detecting other contraband, small-parts inspection, or materials characterization.

  15. X-ray source populations in galaxies

    E-Print Network [OSTI]

    G. Fabbiano

    2005-11-16T23:59:59.000Z

    Today's sensitive, high-resolution X-ray observations allow the study of populations of X-ray sources, in the luminosity range of Galactic X-ray binaries, in galaxies as distant as 20-30 Mpc. The traditional astronomical tools of photometric diagrams and luminosity functions are now applied to these populations, providing a direct probe of the evolved binary component of different stellar populations. The study of the X-ray populations of E and S0 galaxies has revamped the debate on the formation and evolution of low-mass X-ray binaries (LMXBs) and on the role of globular clusters in these processes. While overall stellar mass drives the amount of X-ray binaries in old stellar populations, the amount of sources in star forming galaxies is related to the star formation rate. Short-lived, luminous, high-mass binaries (HMXBs) dominate these young populations. The most luminous sources in these systems are the debated ULXs, which have been suggested to be ~100-1000 Msol black holes, but could alternatively include a number of binaries with stellar mass black holes. Very soft sources have also been discovered in many galaxies and their nature is currently being debated. Observations of the deep X-ray sky, and comparison with deep optical surveys, are providing the first evidence of the X-ray evolution of galaxies.

  16. Quantification of microstructural features in HMX using small angle neutron scattering techniques

    SciTech Connect (OSTI)

    Mang, J.T.; Skidmore, C.B.; Hjelm, R.P.; Howe, P.M.

    1998-12-01T23:59:59.000Z

    Microstructural features in raw powders of High Explosives have been qualitatively observed by many researchers, using polarized light and scanning electron microscopy. Here, the authors present a method for non-destructive quantification of volume fraction and structure of intragranular cracks and crystallization voids in a bulk sample (100--300 mg). By employing Small Angle Neutron Scattering (SANS) in conjunction with the method of contrast variation, they can effectively highlight different structural features of a complex system. The technique of contrast variation relies on immersing the sample in a uniform fluid of known neutron scattering length density. By selectively varying the scattering length density of the immersion fluid, scattering contributions from internal and external structures can be separated. This approach is analogous to varying the index of refraction for immersion oil relative to a sample in polarized light microscopy. SANS experiments on HMX were conducted using loose powders (261 and 10 micron mean particle diameters) and pellets made by uniaxial consolidation (without binder) to 7 and 10 volume percent porosity respectively. Detailed modeling of the SANS data indicate significant alteration of the intragranular void/crack/pore structure, with pressing, of the HMX powders.

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

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

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

    2011-05-01T23:59:59.000Z

    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.

  18. Nuclear surface studies with antiprotonic atom X-rays

    E-Print Network [OSTI]

    Wycech, S; Jastrzebski, J J; Klos, B; Trzcinska, A; Von Egidy, T

    2007-01-01T23:59:59.000Z

    The recent and older level shifts and widths in pbar atoms are analyzed. The results are fitted by an antiproton-nucleus optical potential with two basic complex strength parameters. These parameters are related to average S and P wave scattering parameters in the subthreshold energy region. A fair consistency of the X-ray data for all Z values, stopping pbar data and the Nbar-N scattering data has been achieved. The determination of neutron density profiles at the nuclear surface is undertaken, and the determination of the neutron R_{rms} radii is attempted. Uncertainties due to the input data and the procedure are discussed.

  19. Neutron Scattering Tutorials | Neutron Science | ORNL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Neutron Scattering Tutorials SHARE Neutron Scattering Tutorials The following lectures were presented at the 2011 and 2010 National School on Neutron & X-Ray Scattering. This...

  20. Relativistic Effects on Reflection X-ray Spectra of AGN

    SciTech Connect (OSTI)

    Lee, Khee-Gan; /University Coll. London; Fuerst, Steven V.; /KIPAC, Menlo Park; Brandwardi-Raymond, Graziella; Wu, Kinwah; Crowley, Oliver; /University Coll. London

    2007-01-05T23:59:59.000Z

    We have calculated the reflection component of the X-ray spectra of active galactic nuclei (AGN) and shown that they can be significantly modified by the relativistic motion of the accretion flow and various gravitational effects of the central black hole. The absorption edges in the reflection spectra suffer severe energy shifts and smearing. The degree of distortion depends on the system parameters, and the dependence is stronger for some parameters such as the inner radius of the accretion disk and the disk viewing inclination angles. The relativistic effects are significant and are observable. Improper treatment of the reflection component of the X-ray continuum in spectral fittings will give rise to spurious line-like features, which will mimic the fluorescent emission lines and mask the relativistic signatures of the lines.

  1. Fiber fed x-ray/gamma ray imaging apparatus

    DOE Patents [OSTI]

    Hailey, C.J.; Ziock, K.P.

    1992-06-02T23:59:59.000Z

    X-ray/gamma ray imaging apparatus is disclosed for detecting the position, energy, and intensity of x-ray/gamma ray radiation comprising scintillation means disposed in the path of such radiation and capable of generating photons in response to such radiation; first photodetection means optically bonded to the scintillation means and capable of generating an electrical signal indicative of the intensity, and energy of the radiation detected by the scintillation means; second photodetection means capable of generating an electrical signal indicative of the position of the radiation in the radiation pattern; and means for optically coupling the scintillation means to the second photodetection means. The photodetection means are electrically connected to control and storage means which may also be used to screen out noise by rejecting a signal from one photodetection means not synchronized to a signal from the other photodetection means; and also to screen out signals from scattered radiation. 6 figs.

  2. A novel method for experimental characterization of large-angle scattered particles in scanned carbon-ion therapy

    SciTech Connect (OSTI)

    Hara, Yousuke, E-mail: y-hara@nirs.go.jp; Furukawa, Takuji; Inaniwa, Taku; Mizushima, Kota; Shirai, Toshiyuki; Noda, Koji [Medical Physics Research Group, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan)] [Medical Physics Research Group, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan)

    2014-02-15T23:59:59.000Z

    Purpose: It is essential to consider large-angle scattered particles in dose calculation models for therapeutic carbon-ion beams. However, it is difficult to measure the small dose contribution from large-angle scattered particles. In this paper, the authors present a novel method to derive the parameters describing large-angle scattered particles from the measured results. Methods: The authors developed a new parallel-plate ionization chamber consisting of concentric electrodes. Since the sensitive volume of each channel is increased linearly with this type, it is possible to efficiently and easily detect small contributions from the large-angle scattered particles. The parameters describing the large-angle scattered particles were derived from pencil beam dose distribution in water measured with the new ionization chamber. To evaluate the validity of this method, the correction for the field-size dependence of the doses, “predicted-dose scaling factor,” was calculated with the new parameters. Results: The predicted-dose scaling factor calculated with the new parameters was compared with the existing one. The difference between the new correction factor and the existing one was 1.3%. For target volumes of different sizes, the calculated dose distribution with the new parameters was in good agreement with the measured one. Conclusions: Parameters describing the large-angle scattered particles can be efficiently and rapidly determined using the new ionization chamber. The authors confirmed that the field-size dependence of the doses could be compensated for by the new parameters. This method makes it possible to easily derive the parameters describing the large-angle scattered particles, while maintaining the dose calculation accuracy.

  3. X-Ray Nanoimaging: Instruments and Methods

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengtheningWildfires may contribute more toConsensusX-RayX-Ray ImagingX-Ray

  4. X-ray Synchrotron Radiation in a Plasma Wiggler

    SciTech Connect (OSTI)

    Wang, Shuoquin; /UCLA /SLAC, SSRL

    2005-09-27T23:59:59.000Z

    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.

  5. Initial characterization of mudstone nanoporosity with small angle neutron scattering using caprocks from carbon sequestration sites.

    SciTech Connect (OSTI)

    McCray, John (Colorado School of Mines); Navarre-Sitchler, Alexis (Colorado School of Mines); Mouzakis, Katherine (Colorado School of Mines); Heath, Jason E.; Dewers, Thomas A.; Rother, Gernot (Oak Ridge National Laboratory)

    2010-11-01T23:59:59.000Z

    Geological carbon sequestration relies on the principle that CO{sub 2} injected deep into the subsurface is unable to leak to the atmosphere. Structural trapping by a relatively impermeable caprock (often mudstone such as a shale) is the main trapping mechanism that is currently relied on for the first hundreds of years. Many of the pores of the caprock are of micrometer to nanometer scale. However, the distribution, geometry and volume of porosity at these scales are poorly characterized. Differences in pore shape and size can cause variation in capillary properties and fluid transport resulting in fluid pathways with different capillary entry pressures in the same sample. Prediction of pore network properties for distinct geologic environments would result in significant advancement in our ability to model subsurface fluid flow. Specifically, prediction of fluid flow through caprocks of geologic CO{sub 2} sequestration reservoirs is a critical step in evaluating the risk of leakage to overlying aquifers. The micro- and nanoporosity was analyzed in four mudstones using small angle neutron scattering (SANS). These mudstones are caprocks of formations that are currently under study or being used for carbon sequestration projects and include the Marine Tuscaloosa Group, the Lower Tuscaloosa Group, the upper and lower shale members of the Kirtland Formation, and the Pennsylvanian Gothic shale. Total organic carbon varies from <0.3% to 4% by weight. Expandable clay contents range from 10% to {approx}40% in the Gothic shale and Kirtland Formation, respectively. Neutrons effectively scatter from interfaces between materials with differing scattering length density (i.e. minerals and pores). The intensity of scattered neutrons, I(Q), where Q is the scattering vector, gives information about the volume of pores and their arrangement in the sample. The slope of the scattering data when plotted as log I(Q) vs. log Q provides information about the fractality or geometry of the pore network. Results from this study, combined with high-resolution TEM imaging, provide insight into the differences in volume and geometry of porosity between these various mudstones.

  6. Hard X-ray Fluorescence Measurements of Heteroepitaxial Solid...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hard X-ray Fluorescence Measurements of Heteroepitaxial Solid Oxide Fuel Cell Cathode Materials. Hard X-ray Fluorescence Measurements of Heteroepitaxial Solid Oxide Fuel Cell...

  7. Using X-Ray Computed Tomography in Pore Structure Characterization...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Using X-Ray Computed Tomography in Pore Structure Characterization for a Berea Sandstone: Resolution Effect. Using X-Ray Computed Tomography in Pore Structure Characterization for...

  8. Manipulating X-rays with Tiny Mirrors | Argonne National Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    for controlling X-rays. MEMS, or microelectromechanical systems, allow shrinking the optics to the microscale creating ultrafast devices for reflecting X-rays at precise times...

  9. Fuel Injection and Spray Research Using X-Ray Diagnostics

    Broader source: Energy.gov (indexed) [DOE]

    temperature ambient (plastic windows) 5 Radiography - Monochromatic x-rays - Absorption of x-rays by the fuel - Ensemble averaged (flux limited) - Room temperature ambient...

  10. Fuel Injection and Spray Research Using X-Ray Diagnostics

    Broader source: Energy.gov (indexed) [DOE]

    by ECN using several different techniques - Silicone molds (Valencia) - X-ray absorption tomography (CAT) - X-Ray phase contrast imaging (Argonne) - Microscopy (Sandia) ...

  11. X-ray induced optical reflectivity

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Durbin, Stephen M.

    2012-01-01T23:59:59.000Z

    The change in optical reflectivity induced by intense x-ray pulses can now be used to study ultrafast many body responses in solids in the femtosecond time domain. X-ray absorption creates photoelectrons and core level holes subsequently filled by Auger or fluorescence processes, and these excitations ultimately add conduction and valence band carriers that perturb optical reflectivity.Optical absorption associated with band filling and band gap narrowing is shown to explain the basic features found in recent measurements on an insulator (silicon nitride, Si3N4), a semiconductor(gallium arsenide,GaAs), and a metal (gold,Au), obtained with ?100 fs x-ray pulses at 500-2000 eV and probed with 800 nm laser pulses. In particular GaAs exhibits an abrupt drop in reflectivity, persisting only for a time comparable to the x-ray excitation pulse duration, consistent with prompt band gap narrowing.

  12. Columbia University X-Ray Measurements

    E-Print Network [OSTI]

    Columbia University X-Ray Measurements of the Levitated Dipole Experiment J. L. Ellsworth, J. Kesner MIT Plasma Science and Fusion Center D.T. Garnier, A.K. Hansen, M.E. Mauel Columbia University

  13. Lensless X-Ray Imaging in Reflection

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Imaging in Reflection Print Wednesday, 26 October 2011 00:00 The advent of x-ray free-electron laser (XFEL) light sources has led to an outburst of research activities in the field...

  14. X-ray source for mammography

    DOE Patents [OSTI]

    Logan, Clinton M. (Pleasanton, CA)

    1994-01-01T23:59:59.000Z

    An x-ray source utilizing anode material which shifts the output spectrum to higher energy and thereby obtains higher penetrating ability for screening mammography application, than the currently utilized anode material. The currently used anode material (molybdenum) produces an energy x-ray spectrum of 17.5/19.6 keV, which using the anode material of this invention (e.g. silver, rhodium, and tungsten) the x-ray spectrum would be in the 20-35 keV region. Thus, the anode material of this invention provides for imaging of breasts with higher than average x-ray opacity without increase of the radiation dose, and thus reduces the risk of induced breast cancer due to the radiation dose administered for mammograms.

  15. X-ray source for mammography

    DOE Patents [OSTI]

    Logan, C.M.

    1994-12-20T23:59:59.000Z

    An x-ray source is described utilizing anode material which shifts the output spectrum to higher energy and thereby obtains higher penetrating ability for screening mammography application, than the currently utilized anode material. The currently used anode material (molybdenum) produces an energy x-ray spectrum of 17.5/19.6 keV, which using the anode material of this invention (e.g. silver, rhodium, and tungsten) the x-ray spectrum would be in the 20-35 keV region. Thus, the anode material of this invention provides for imaging of breasts with higher than average x-ray opacity without increase of the radiation dose, and thus reduces the risk of induced breast cancer due to the radiation dose administered for mammograms. 6 figures.

  16. Time-domain sampling of x-ray pulses using an ultrafast sample response

    SciTech Connect (OSTI)

    Gaal, P.; Shayduk, R. [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Wilhelm-Conrad-Roentgen Campus, BESSY II, Albert-Einstein-Str. 15, 12489 Berlin (Germany); Schick, D.; Herzog, M.; Bojahr, A.; Goldshteyn, J.; Navirian, H. A.; Leitenberger, W. [Institut fuer Physik und Astronomie, Universitaet Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam (Germany); Vrejoiu, I. [Max-Planck-Institut fuer Mikrostrukturphysik, Weinberg 2, 06120 Halle (Germany); Khakhulin, D.; Wulff, M. [European Synchrotron Radiation Facility (ESRF), 6 rue Jules Horowitz, 38000 Grenoble (France); Bargheer, M. [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Wilhelm-Conrad-Roentgen Campus, BESSY II, Albert-Einstein-Str. 15, 12489 Berlin (Germany); Institut fuer Physik und Astronomie, Universitaet Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam (Germany)

    2012-12-10T23:59:59.000Z

    We employ the ultrafast response of a 15.4 nm thin SrRuO{sub 3} layer grown epitaxially on a SrTiO{sub 3} substrate to perform time-domain sampling of an x-ray pulse emitted from a synchrotron storage ring. Excitation of the sample with an ultrashort laser pulse triggers coherent expansion and compression waves in the thin layer, which turn the diffraction efficiency on and off at a fixed Bragg angle during 5 ps. This is significantly shorter than the duration of the synchrotron x-ray pulse of 100 ps. Cross-correlation measurements of the ultrafast sample response and the synchrotron x-ray pulse allow to reconstruct the x-ray pulse shape.

  17. Principles of X-ray Navigation

    SciTech Connect (OSTI)

    Hanson, John Eric; /SLAC

    2006-03-17T23:59:59.000Z

    X-ray navigation is a new concept in satellite navigation in which orientation, position and time are measured by observing stellar emissions in x-ray wavelengths. X-ray navigation offers the opportunity for a single instrument to be used to measure these parameters autonomously. Furthermore, this concept is not limited to missions in close proximity to the earth. X-ray navigation can be used on a variety of missions from satellites in low earth orbit to spacecraft on interplanetary missions. In 1997 the Unconventional Stellar Aspect Experiment (USA) will be launched as part of the Advanced Research and Global Observation Satellite (ARGOS). USA will provide the first platform for real-time experimentation in the field of x-ray navigation and also serves as an excellent case study for the design and manufacturing of space qualified systems in small, autonomous groups. Current techniques for determining the orientation of a satellite rely on observations of the earth, sun and stars in infrared, visible or ultraviolet wavelengths. It is possible to use x-ray imaging devices to provide arcsecond level measurement of attitude based on star patterns in the x-ray sky. This technique is explored with a simple simulation. Collimated x-ray detectors can be used on spinning satellites to provide a cheap and reliable measure of orientation. This is demonstrated using observations of the Crab Pulsar taken by the high Energy Astronomy Observatory (HEAO-1) in 1977. A single instrument concept is shown to be effective, but dependent on an a priori estimate of the guide star intensity and thus susceptible to errors in that estimate. A star scanner based on a differential measurement from two x-ray detectors eliminates the need for an a priori estimate of the guide star intensity. A first order model and a second order model of the two star scanner concepts are considered. Many of the stars that emit in the x-ray regime are also x-ray pulsars with frequency stability approaching a part in 10{sup 9}. By observing these pulsations, a satellite can keep accurate time autonomously. They have demonstrated the acquisition and tracking of the Crab nebula pulsar by simulating the operation of a phase-locked loop.

  18. Waveguide detection of right-angle-scattered light in flow cytometry

    DOE Patents [OSTI]

    Mariella, Jr., Raymond P. (Danville, CA)

    2000-01-01T23:59:59.000Z

    A transparent flow cell is used as an index-guided optical waveguide. A detector for the flow cell but not the liquid stream detects the Right-Angle-Scattered (RAS) Light exiting from one end of the flow cell. The detector(s) could view the trapped RAS light from the flow cell either directly or through intermediate optical light guides. If the light exits one end of the flow cell, then the other end of the flow cell can be given a high-reflectivity coating to approximately double the amount of light collected. This system is more robust in its alignment than the traditional flow cytometry systems which use imaging optics, such as microscope objectives.

  19. Bending elasticity of a curved amphiphilic film decorated anchored copolymers: a small angle neutron scattering study

    E-Print Network [OSTI]

    Jacqueline Appell; Christian Ligoure; Gregoire Porte

    2004-06-30T23:59:59.000Z

    Microemulsion droplets (oil in water stabilized by a surfactant film) are progressively decorated with increasing amounts of poly ethylene- oxide (PEO) chains anchored in the film by the short aliphatic chain grafted at one end of the PEO chain . The evolution of the bending elasticity of the surfactant film with increasing decoration is deduced from the evolution in size and polydispersity of the droplets as reflected by small angle neutron scattering. The optimum curvature radius decreases while the bending rigidity modulus remains practically constant. The experimental results compare well with the predictions of a model developed for the bending properties of a curved film decorated by non-adsorbing polymer chains, which takes into account, the finite curvature of the film and the free diffusion of the chains on the film.

  20. Small angle neutron scattering analysis of novel carbons for lithium secondary batteries.

    SciTech Connect (OSTI)

    Sandi, G.; Thiyagarajan, P.; Winans, R.; Carrado, K.

    1998-01-14T23:59:59.000Z

    Small angle neutron scattering analyses of carbonaceous materials used as anodes in lithium ion cells have been performed. The carbons have been synthesized using pillared clays (PILCs) as inorganic templates. Pillared clays are layered silicates whose sheets have been permanently propped open by sets of thermally stable molecular props. The calcined PILC was loaded with five different organic precursors and heated at 700 C under nitrogen. When the inorganic pillars were removed by acid treatment, carbon sheets are produced with holes. The fitting of the data in the high q region suggested that the carbon sheets have voids with radii ranging from 4 to 8 {angstrom}. Similar radii were obtained for the PILC and PILC/organic precursor, which suggests that the carbon was well distributed in the clay prior to pyrolysis.

  1. Borman effect in resonant diffraction of X-rays

    SciTech Connect (OSTI)

    Oreshko, A. P., E-mail: ap.oreshko@physics.msu.ru [Moscow State University (Russian Federation)

    2013-08-15T23:59:59.000Z

    A dynamic theory of resonant diffraction (occurring when the energy of incident radiation is close to the energy of the absorption edge of an element in the composition of a given substance) of synchronous X-rays is developed in the two-wave approximation in the coplanar Laue geometry for large grazing angles in perfect crystals. A sharp decrease in the absorption coefficient in the substance with simultaneously satisfied diffraction conditions (Borman effect) is demonstrated, and the theoretical and first experimental results are compared. The calculations reveal the possibility of applying this approach in analyzing the quadrupole-quadrupole contribution to the absorption coefficient.

  2. Characteristic x-ray emission from undermines plasmas irradiated by ultra-intense lasers

    SciTech Connect (OSTI)

    Niemann, Christoph

    2012-05-05T23:59:59.000Z

    Between FY09 and FY11 we have conducted more than a dozen three-week experimental campaigns at high-power laser facilities around the world to investigate laser-channeling through x-ray and optical imaging and the conversion from laser-energy to xrays. We have performed simultaneous two-wavelength x-ray imaging (K-alpha and He-alpha) to distinguish the hot-plasma region (hot-spot) from the laser-produced electrons (K-alpha). In addition, we have initiated a new collaboration with SNL and have performed first shots on the 100 TW beamlet chamber to commission a fast x-ray streak camera to be used to investigate the temporal evolution of our K-alpha sources. We also collaborated on campaigns at the Rutherford Appleton Laboratory (UK) and the LANL Trident laser to employ laser produced x-ray sources for Thomson scattering off dense matter.

  3. The MOLLER Experiment: An Ultra-Precise Measurement of the Weak Mixing Angle Using Møller Scattering

    E-Print Network [OSTI]

    MOLLER Collaboration; J. Benesch; P. Brindza; R. D. Carlini; J-P. Chen; E. Chudakov; S. Covrig; M. M. Dalton; A. Deur; D. Gaskell; A. Gavalya; J. Gomez; D. W. Higinbotham; C. Keppel; D. Meekins; R. Michaels; B. Moffit; Y. Roblin; R. Suleiman; R. Wines; B. Wojtsekhowski; G. Cates; D. Crabb; D. Day; K. Gnanvo; D. Keller; N. Liyanage; V. V. Nelyubin; H. Nguyen; B. Norum; K. Paschke; V. Sulkosky; J. Zhang; X. Zheng; J. Birchall; P. Blunden; M. T. W. Gericke; W. R. Falk; L. Lee; J. Mammei; S. A. Page; W. T. H. van Oers; K. Dehmelt; A. Deshpande; N. Feege; T. K. Hemmick; K. S. Kumar; T. Kutz; R. Miskimen; M. J. Ramsey-Musolf; S. Riordan; N. Hirlinger Saylor; J. Bessuille; E. Ihloff; J. Kelsey; S. Kowalski; R. Silwal; G. De Cataldo; R. De Leo; D. Di Bari; L. Lagamba; E. NappiV. Bellini; F. Mammoliti; F. Noto; M. L. Sperduto; C. M. Sutera; P. Cole; T. A. Forest; M. Khandekar; D. McNulty; K. Aulenbacher; S. Baunack; F. Maas; V. Tioukine; R. Gilman; K. Myers; R. Ransome; A. Tadepalli; R. Beniniwattha; R. Holmes; P. Souder; D. S. Armstrong; T. D. Averett; W. Deconinck; W. Duvall; A. Lee; M. L. Pitt; J. A. Dunne; D. Dutta; L. El Fassi; F. De Persio; F. Meddi; G. M. Urciuoli; E. Cisbani; C. Fanelli; F. Garibaldi; K. Johnston; N. Simicevic; S. Wells; P. M. King; J. Roche; J. Arrington; P. E. Reimer; G. Franklin; B. Quinn; A. Ahmidouch; S. Danagoulian; O. Glamazdin; R. Pomatsalyuk; R. Mammei; J. W. Martin; T. Holmstrom; J. Erler; Yu. G. Kolomensky; J. Napolitano; K. A. Aniol; W. D. Ramsay; E. Korkmaz; D. T. Spayde; F. Benmokhtar; A. Del Dotto; R. Perrino; S. Barkanova; A. Aleksejevs; J. Singh

    2014-12-03T23:59:59.000Z

    The physics case and an experimental overview of the MOLLER (Measurement Of a Lepton Lepton Electroweak Reaction) experiment at the 12 GeV upgraded Jefferson Lab are presented. A highlight of the Fundamental Symmetries subfield of the 2007 NSAC Long Range Plan was the SLAC E158 measurement of the parity-violating asymmetry $A_{PV}$ in polarized electron-electron (M{\\o}ller) scattering. The proposed MOLLER experiment will improve on this result by a factor of five, yielding the most precise measurement of the weak mixing angle at low or high energy anticipated over the next decade. This new result would be sensitive to the interference of the electromagnetic amplitude with new neutral current amplitudes as weak as $\\sim 10^{-3}\\cdot G_F$ from as yet undiscovered dynamics beyond the Standard Model. The resulting discovery reach is unmatched by any proposed experiment measuring a flavor- and CP-conserving process over the next decade, and yields a unique window to new physics at MeV and multi-TeV scales, complementary to direct searches at high energy colliders such as the Large Hadron Collider (LHC). The experiment takes advantage of the unique opportunity provided by the upgraded electron beam energy, luminosity, and stability at Jefferson Laboratory and the extensive experience accumulated in the community after a round of recent successfully completed parity-violating electron scattering experiments

  4. Small Angle Neutron Scattering Study of Conformation of Oligo(ethylene glycol)-Grafted Polystyrene in Dilute Solutions: Effect of the Backbone Length

    E-Print Network [OSTI]

    Small Angle Neutron Scattering Study of Conformation of Oligo(ethylene glycol)- Grafted Polystyrene Fengjun Hua,2 Kunlun Hong,2 and Jimmy W. Mays2 1Neutron Scattering Sciences Division, ORNL 2Center

  5. A theoretical analysis of reflection of X-rays from water at energies relevant for diagnostics

    SciTech Connect (OSTI)

    Arsenovic, Dusan [Institute of Physics, Pregrevica 118, P.O. Box 57, Belgrade (Serbia and Montenegro); Davidovic, Dragomir M.; Vukanic, Jovan [Vinca Institute of Nuclear Sciences, P.O Box 522, Belgrade (Serbia and Montenegro)

    2003-01-24T23:59:59.000Z

    The reflection of X-rays from a semi-infinite water target, for energies used in X-ray diagnostics, is treated by the analog Monte Carlo simulation. In the developed procedure it was possible to calculate separately contributions of photons scattered, before reflection, fixed number of times with target electrons. It turned out that multiple collision type of reflection dominates at all energies investigated, whenever the absorption is small. The same process was also treated analytically as the classical albedo problem for isotropic scattering without energy loss. Very good agreement of results of the two approaches is obtained.

  6. Structure of spontaneously formed solid-electrolyte interphase on lithiated graphite determined using small-angle neutron scattering

    SciTech Connect (OSTI)

    Sacci, Robert L [ORNL; Banuelos, Jose Leo [ORNL; Veith, Gabriel M [ORNL; Littrell, Ken [ORNL; Cheng, Yongqiang [ORNL; Wildgruber, Christoph U [ORNL; Jones, Lacy L [ORNL; Ramirez-Cuesta, Anibal J [ORNL; Rother, Gernot [ORNL; Dudney, Nancy J [ORNL

    2015-01-01T23:59:59.000Z

    We report the first small-angle neutron scattering of a chemically formed solid-electrolyte interphase from LixC6 reacting with ethylene carbonate/dimethyl carbon solvent. This provides a different and perhaps simpler view of SEI formation than the usual electrochemically-driven reaction. We show that an organic layer coats the graphite particles filling in micro-pores and is polymeric in nature being 1-3 nm thick. We used inelastic neutron scattering to probe the chemistry, and we found that the SEI showed similar inelastic scattering to polyethylene oxide.

  7. Differential phase contrast X-ray imaging system and components

    DOE Patents [OSTI]

    Stutman, Daniel; Finkenthal, Michael

    2014-07-01T23:59:59.000Z

    A differential phase contrast X-ray imaging system includes an X-ray illumination system, a beam splitter arranged in an optical path of the X-ray illumination system, and a detection system arranged in an optical path to detect X-rays after passing through the beam splitter.

  8. Radiographic X-Ray Pulse Jitter

    SciTech Connect (OSTI)

    Mitton, C. V., Good, D. E., Henderson, D. J., Hogge, K. W.

    2011-01-15T23:59:59.000Z

    The Dual Beam Radiographic Facility consists of two identical radiographic sources. Major components of the machines are: Marx generator, water-filled pulse-forming line (PFL), water-filled coaxial transmission line, three-cell inductive voltage adder, and rod-pinch diode. The diode pulse has the following electrical specifications: 2.25-MV, 60-kA, 60-ns. Each source has the following x-ray parameters: 1-mm-diameter spot size, 4-rad at 1 m, 50-ns full width half max. The x-ray pulse is measured with PIN diode detectors. The sources were developed to produce high resolution images on single-shot, high-value experiments. For this application it is desirable to maintain a high level of reproducibility in source output. X-ray pulse jitter is a key metric for analysis of reproducibility. We will give measurements of x-ray jitter for each machine. It is expected that x-ray pulse jitter is predominantly due to PFL switch jitter, and therefore a correlation of the two will be discussed.

  9. Oscillations During Thermonuclear X-ray Bursts

    E-Print Network [OSTI]

    Tod E. Strohmayer

    2001-01-12T23:59:59.000Z

    High amplitude, nearly coherent X-ray brightness oscillations during thermonuclear X-ray bursts were discovered with the Rossi X-ray Timing Explorer (RXTE) in early 1996. Spectral and timing evidence strongly supports the conclusion that these oscillations are caused by rotational modulation of the burst emission and that they reveal the spin frequency of neutron stars in low mass X-ray binaries, a long sought goal of X-ray astronomy. Studies carried out over the past year have led to the discovery of burst oscillations in four new sources, bringing to ten the number with confirmed burst oscillations. I review the status of our knowledge of these oscillations and indicate how they can be used to probe the physics of neutron stars. For a few burst oscillation sources it has been proposed that the strongest and most ubiquitous frequency is actually the first overtone of the spin frequency and hence that two nearly antipodal hot spots are present on the neutron star. This inference has important implications for both the physics of thermonuclear burning as well as the mass - radius relation for neutron stars, so its confirmation is crucial. I discuss recent attempts to confirm this hypothesis for 4U 1636-53, the source for which a signal at the putative fundamental (290 Hz) has been claimed.

  10. X-RAY SPECTROMETRY X-Ray Spectrom. 2007; 36: 336342

    E-Print Network [OSTI]

    Limburg, Karin E.

    , Chicago, IL 60637, USA 3 Cornell High Energy Synchrotron Source and School of Applied and EngineeringX-RAY SPECTROMETRY X-Ray Spectrom. 2007; 36: 336­342 Published online in Wiley InterScience (www to establish a breakthrough in high-resolution, simultaneous area mapping of multiple trace elements

  11. In Operando X-ray Diffraction and Transmission X-ray Microscopy of Lithium Sulfur Batteries

    E-Print Network [OSTI]

    Cui, Yi

    In Operando X-ray Diffraction and Transmission X-ray Microscopy of Lithium Sulfur Batteries Johanna Information ABSTRACT: Rechargeable lithium-sulfur (Li-S) batteries hold great potential for high of these batteries for commercial use. The two primary obstacles are the solubility of long chain lithium

  12. Characterization of the effects of x-ray irradiation on the hierarchical structure and mechanical properties of human cortical bone

    SciTech Connect (OSTI)

    Barth, Holly; Zimmermann, Elizabeth; Schaible, Eric; Tang, Simon; Alliston, Tamara; Ritchie, Robert

    2011-08-19T23:59:59.000Z

    Bone comprises a complex structure of primarily collagen, hydroxyapatite and water, where each hierarchical structural level contributes to its strength, ductility and toughness. These properties, however, are degraded by irradiation, arising from medical therapy or bone-allograft sterilization. We provide here a mechanistic framework for how irradiation affects the nature and properties of human cortical bone over a range of characteristic (nano to macro) length-scales, following x-­ray exposures up to 630 kGy. Macroscopically, bone strength, ductility and fracture resistance are seen to be progressively degraded with increasing irradiation levels. At the micron-­scale, fracture properties, evaluated using in-situ scanning electron microscopy and synchrotron x-ray computed micro-tomography, provide mechanistic information on how cracks interact with the bone-matrix structure. At sub-micron scales, strength properties are evaluated with in-situ tensile tests in the synchrotron using small-/wide-angle x-ray scattering/diffraction, where strains are simultaneously measured in the macroscopic tissue, collagen fibrils and mineral. Compared to healthy bone, results show that the fibrillar strain is decreased by ~40% following 70 kGy exposures, consistent with significant stiffening and degradation of the collagen. We attribute the irradiation-­induced deterioration in mechanical properties to mechanisms at multiple length-scales, including changes in crack paths at micron-­scales, loss of plasticity from suppressed fibrillar sliding at sub-­micron scales, and the loss and damage of collagen at the nano-­scales, the latter being assessed using Raman and Fourier-Transform-Infrared spectroscopy and a fluorometric assay.

  13. Frontiers in X-Ray Science

    SciTech Connect (OSTI)

    Linda Young

    2011-02-23T23:59:59.000Z

    The year 2010 marked the fiftieth anniversary of the optical laser and the first anniversary of the world's first hard x-ray free-electron laser, the Linac Coherent Light Source (LCLS) at SLAC. This exciting, new accelerator-based source of x-rays provides peak brilliances roughly a billion times greater than currently available from synchrotron sources such as the Advanced Photon Source at Argonne, and thus explores a qualitatively different parameter space. This talk will describe the first experiments at the LCLS aimed at understanding the nature of high intensity x-ray interactions, related applications in ultrafast imaging on the atomic scale and sketch nascent plans for the extension of both linac and storage-ring based photon sources.

  14. The X-ray/submillimetre link

    E-Print Network [OSTI]

    O. Almaini

    2000-01-07T23:59:59.000Z

    It is widely believed that most of the cosmic X-ray background (XRB) is produced by a vast, hitherto undetected population of obscured AGN. Deep X-ray surveys with Chandra and XMM will soon test this hypothesis. Similarly, recent sub-mm surveys with SCUBA have revealed an analogous population of exceptionally luminous, dust-enshrouded {\\em star-forming} galaxies at high redshift. There is now growing evidence for an intimate link between these obscured populations. There are currently large uncertainties in the models, but several independent arguments lead to the conclusion that a significant fraction of the SCUBA sources ($10-30% $) will contain quasars. Recent observational studies of SCUBA survey sources appear to confirm these predictions, although the relative roles of AGN and star-forming activity in heating the dust are unclear. Forthcoming surveys combining X-ray and sub-mm observations will provide a very powerful tool for disentangling these processes.

  15. X-ray atlas of rheumatic diseases

    SciTech Connect (OSTI)

    Dihlmann, W.

    1986-01-01T23:59:59.000Z

    This atlas comprises instructive X-rays of the various inflammatory rheumatic joint diseases in all stages at the extremities and the spinal column. In addition, the complex pattern of the wide range of arthroses, also known as degenerative rheumatic disease is included. Besides the instructive pointers to X-ray diagnosis, the book is also a guide to differential diagnosis. Hence, this book is actually an X-ray atlas of joint diseases in general. Selected Contents: Introduction: What Does ''Rheumatism'' Actually Mean./Radiographic Methodology in Rheumatic Diseases of the Locomotor System/The Mosaic of Arthritis/Adult Rheumatoid Arthritis/Seronegative Spondylarthritis/Classic Collagen Diseases/Enthesiopathies/Gout-Pseudogout

  16. Combined microstructure x-ray optics

    SciTech Connect (OSTI)

    Barbee, T.W. Jr.

    1989-02-01T23:59:59.000Z

    Multilayers are man-made microstructures which vary in depth and are now of sufficient quality to be used as x-ray, soft x-ray and extreme ultraviolet optics. Gratings are man-made in plane microstructures which have been used as optic elements for most of this century. Joining of these two optical microstructures to form combined microstructure optical microstructures to form combined microstructure optical elements has the potential for greatly enhancing both the throughput and the resolution attainable in these spectral ranges. The characteristics of these new optic elements will be presented and compared to experiment with emphasis on the unique properties of these combined microstructures. These results reported are general in nature and not limited to the soft x-ray or extreme ultraviolet spectral domains and also apply to neutrons. 19 refs., 7 figs., 4 tabs.

  17. X-ray reflectivity and surface roughness

    SciTech Connect (OSTI)

    Ocko, B.M.

    1988-01-01T23:59:59.000Z

    Since the advent of high brightness synchrotron radiation sources there has been a phenomenal growth in the use of x-rays as a probe of surface structure. The technique of x-ray reflectivity is particularly relevant to electrochemists since it is capable of probing the structure normal to an electrode surface in situ. In this paper the theoretical framework for x-ray reflectivity is reviewed and the results from previous non-electrochemistry measurements are summarized. These measurements are from the liquid/air interface (CCl/sub 4/), the metal crystal vacuum interface (Au(100)), and from the liquid/solid interface(liquid crystal/silicon). 34 refs., 5 figs.

  18. Parameterization of structures in HE composites using surrogate materials: A small angle neutron scattering investigation

    SciTech Connect (OSTI)

    Mang, J.T.; Hjelm, R.P.; Skidmore, C.B.; Howe, P.M.

    1996-07-01T23:59:59.000Z

    High explosive materials used in the nuclear stockpile are composites of crystalline high explosives (HE) with binder materials, such as Estane. In such materials, there are naturally occurring density fluctuations (defects) due to cracks, internal (in the HE) and external (in the binder) voids and other artifacts of preparation. Changes in such defects due to material aging can affect the response of explosives due to shock, impact and thermal loading. Modeling efforts are attempting to provide quantitative descriptions of explosive response from the lowest ignition thresholds to the development of full blown detonations and explosions, however, adequate descriptions of these processes require accurate measurements of a number of structural parameters of the HE composite. Since different defects are believed to affect explosive sensitivity in different ways it is necessary to quantitatively differentiate between defect types. The authors report here preliminary results of SANS measurements on surrogates for HE materials. The objective of these measurements was to develop methodologies using SANS techniques to parameterize internal void size distributions in a surrogate material, sugar, to simulate an HE used in the stockpile, HMX. Sugar is a natural choice as a surrogate material, as it has the same crystal structure, has similar intragranular voids and has similar mechanical properties as HMX. It is used extensively as a mock material for explosives. Samples were used with two void size distributions: one with a sufficiently small mean particle size that only small occluded voids are present in significant concentrations, and one where the void sizes could be larger. By using methods in small-angle neutron scattering, they were able to isolate the scattering arising from particle-liquid interfaces and internal voids.

  19. High-Energy X-ray Studies of Real Materials Under Real Conditions and in Real Time

    SciTech Connect (OSTI)

    Almer, Jonathan (ANL) [ANL

    2011-05-11T23:59:59.000Z

    High-energy x-rays from 3rd generation synchrotron sources, including the APS, possess a unique combination of high penetration power and high spatial, reciprocal space, and temporal resolution. These characteristics can be exploited to non-destructively measure phase, texture and strain distributions under extreme environments including thermo-mechanical loading, high-pressure, irradiation and supercritical environments. Over the past several years, the 1-ID beamline has developed a number of programs for these purposes, namely (i) high-energy diffraction microscopy, in which grain and sub-grain volumes are mapped in polycrystalline aggregates, and (ii) combined small-and wide-angle x-ray scattering which permits information over a broad range of length scales to be collected from the same (micron-level) volume. These programs have been increasingly used to test and extend predictive simulations of materials behavior over size scales ranging from nm to mm. Select studies will be presented including nucleation and growth of nanomaterials, void and structural evolution in complex composites under thermo-mechanical and irradiated environments, and microstructural changes in layered systems including thermal-barrier coatings, batteries and fuel cells. Finally, extension of these programs, through the planned APS upgrade, to higher spatio-temporal resolution will be described.

  20. X-ray-induced electronic structure change in CuIr{sub 2}S{sub 4}

    SciTech Connect (OSTI)

    Gretarsson, H.; Kim, Young-June [Department of Physics, University of Toronto, 60 St. George Street, Toronto, Ontario M5S 1A7 (Canada); Kim, Jungho; Casa, D.; Gog, T. [CMC-XOR, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Choi, K. R. [l-PEM, Pohang University of Science and Technology, Pohang 790-784 (Korea, Republic of); Cheong, S. W. [l-PEM, Pohang University of Science and Technology, Pohang 790-784 (Korea, Republic of); R-CEM and Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854 (United States)

    2011-09-15T23:59:59.000Z

    The electronic structure of CuIr{sub 2}S{sub 4} is investigated using various bulk-sensitive x-ray spectroscopic methods near the Ir L{sub 3} edge: resonant inelastic x-ray scattering (RIXS), x-ray absorption spectroscopy in the partial fluorescence yield mode, and resonant x-ray emission spectroscopy. A strong RIXS signal (0.75 eV) resulting from a charge-density-wave gap opening is observed below the metal-insulator transition temperature of 230 K. The resultant modification of electronic structure is consistent with the density functional theory prediction. In the spin- and charge-dimer disordered phase induced by x-ray irradiation below 50 K, we find that a broad peak around 0.4 eV appears in the RIXS spectrum.

  1. A Lack of Radio Emission from Neutron Star Low Mass X-ray Binaries

    E-Print Network [OSTI]

    Michael P. Muno; Tomaso Belloni; Vivek Dhawan; Edward H. Morgan; Ronald A. Remillard; Michael P. Rupen

    2004-11-11T23:59:59.000Z

    We report strict upper limits to the radio luminosities of three neutron star low-mass X-ray binaries obtained with the Very Large Array while they were in hard X-ray states as observed with the Rossi X-ray Timing Explorer: 1E 1724-307, 4U 1812-12, and SLX 1735-269. We compare these upper limits to the radio luminosities of several black hole binaries in very similar hard states, and find that the neutron star systems are as faint as or fainter than all of the black hole candidates. The differences in luminosities can partly be attributed to the lower masses of the neutron star systems, which on theoretical and observational grounds are expected to decrease the radio luminosities as M^0.8. However, there still remains a factor of 30 scatter in the radio luminosities of black hole and neutron star X-ray binaries, particularly at X-ray luminosities of a few percent Eddington. We find no obvious differences in the X-ray timing and spectral properties that can be correlated with the radio luminosity. We discuss the implications of these results on current models for the relationship between accretion and jets.

  2. Radiobiological studies using gamma and x rays.

    SciTech Connect (OSTI)

    Potter, Charles Augustus; Longley, Susan W.; Scott, Bobby R. [Lovelace Respiratory Research Institute, Albuquerque, NM; Lin, Yong [Lovelace Respiratory Research Institute, Albuquerque, NM; Wilder, Julie [Lovelace Respiratory Research Institute, Albuquerque, NM; Hutt, Julie A. [Lovelace Respiratory Research Institute, Albuquerque, NM; Padilla, Mabel T. [Lovelace Respiratory Research Institute, Albuquerque, NM; Gott, Katherine M. [Lovelace Respiratory Research Institute, Albuquerque, NM

    2013-02-01T23:59:59.000Z

    There are approximately 500 self-shielded research irradiators used in various facilities throughout the U.S. These facilities use radioactive sources containing either 137Cs or 60Co for a variety of biological investigations. A report from the National Academy of Sciences[1] described the issues with security of particular radiation sources and the desire for their replacement. The participants in this effort prepared two peer-reviewed publications to document the results of radiobiological studies performed using photons from 320-kV x rays and 137Cs on cell cultures and mice. The effectiveness of X rays was shown to vary with cell type.

  3. Energy resolved X-ray grating interferometry

    SciTech Connect (OSTI)

    Thuering, T.; Stampanoni, M. [Swiss Light Source, Paul Scherrer Institut, Villigen PSI (Switzerland) [Swiss Light Source, Paul Scherrer Institut, Villigen PSI (Switzerland); Institute for Biomedical Engineering, Swiss Federal Institute of Technology, Zurich (Switzerland); Barber, W. C.; Iwanczyk, J. S. [DxRay, Inc., Northridge, California 91324 (United States)] [DxRay, Inc., Northridge, California 91324 (United States); Seo, Y.; Alhassen, F. [UCSF Physics Research Laboratory, Department of Radiology and Biomedical Imaging, University of California, San Francisco, California 94143 (United States)] [UCSF Physics Research Laboratory, Department of Radiology and Biomedical Imaging, University of California, San Francisco, California 94143 (United States)

    2013-05-13T23:59:59.000Z

    Although compatible with polychromatic radiation, the sensitivity in X-ray phase contrast imaging with a grating interferometer is strongly dependent on the X-ray spectrum. We used an energy resolving detector to quantitatively investigate the dependency of the noise from the spectral bandwidth and to consequently optimize the system-by selecting the best energy band matching the experimental conditions-with respect to sensitivity maximization and, eventually, dose. Further, since theoretical calculations of the spectrum are usually limited due to non-ideal conditions, an energy resolving detector accurately quantifies the spectral changes induced by the interferometer including flux reduction and beam hardening.

  4. X-Ray Nanoimaging: Instruments and Methods

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengtheningWildfires may contribute more toConsensusX-RayX-Ray

  5. Small angle neutron scattering characterization of the porous structure of carbons prepared using inorganic templates

    SciTech Connect (OSTI)

    Sandi, G.; Thiyagarajan, P.; Carrado, K.A.; Winans, R.E. [Argonne National Lab., IL (United States)] [Argonne National Lab., IL (United States)

    1999-02-01T23:59:59.000Z

    Small angle neutron scattering (SANS) was used for the characterization of the microstructure of carbons derived from organic-loaded inorganic template materials that are used as anodes in lithium ion cells. Pillared clays (PILC), layered silicates whose sheets have been permanently propped open by sets of thermally stable molecular props, were used as a template to load the organic precursors. Five organic precursors, namely pyrene, styrene, pyrene/trioxane copolymer, ethylene, and propylene, were used to load the PILC. Pyrolysis was carried out at 700 C under nitrogen atmosphere. From SANS, information has been derived about the pore radius, mass fractal dimension, and the cutoff length (above which the fractal property breaks down) on each carbon. In general, the pore radius ranges from 4 to 11 {angstrom}, and the mass fractal dimension varies in the range from 2.5 to 2.9. Contrast-match SANS studies of carbons wetted in 84% deuterated toluene indicate that a significant amount of pores in carbon from pyrene are not accessible to the solvent, while most of the porous network of carbon from propylene is accessible.

  6. Measurement of the running of the QED coupling in small-angle Bhabha scattering at LEP

    E-Print Network [OSTI]

    The OPAL Collaboration; G. Abbiendi

    2006-02-23T23:59:59.000Z

    Using the OPAL detector at LEP, the running of the effective QED coupling alpha(t) is measured for space-like momentum transfer from the angular distribution of small-angle Bhabha scattering. In an almost ideal QED framework, with very favourable experimental conditions, we obtain: Delta alpha(-6.07GeV^2) - Delta alpha(-1.81GeV^2) = (440 pm 58 pm 43 pm 30) X 10^-5, where the first error is statistical, the second is the experimental systematic and the third is the theoretical uncertainty. This agrees with current evaluations of alpha(t).The null hypothesis that alpha remains constant within the above interval of -t is excluded with a significance above 5sigma. Similarly, our results are inconsistent at the level of 3sigma with the hypothesis that only leptonic loops contribute to the running. This is currently the most significant direct measurment where the running alpha(t) is probed differentially within the measured t range.

  7. Soluble Hydrogen-bonding Interpolymer Complexes in Water: A Small-Angle Neutron Scattering Study

    E-Print Network [OSTI]

    Maria Sotiropoulou; Julian Oberdisse; Georgios Staikos

    2006-04-03T23:59:59.000Z

    The hydrogen-bonding interpolymer complexation between poly(acrylic acid) (PAA) and the poly(N,N-dimethylacrylamide) (PDMAM) side chains of the negatively charged graft copolymer poly(acrylic acid-co-2-acrylamido-2-methyl-1-propane sulfonic acid)-graft-poly(N, N dimethylacrylamide) (P(AA-co-AMPSA)-g-PDMAM), containing 48 wt % of PDMAM, and shortly designated as G48, has been studied by small-angle neutron scattering in aqueous solution. Complexation occurs at low pH (pH < 3.75), resulting in the formation of negatively charged colloidal particles, consisting of PAA/PDMAM hydrogen-bonding interpolymer complexes, whose radius is estimated to be around 165 A. As these particles involve more than five graft copolymer chains, they act as stickers between the anionic chains of the graft copolymer backbone. This can explain the characteristic thickening observed in past rheological measurements with these mixtures in the semidilute solution, with decreasing pH. We have also examined the influence of pH and PAA molecular weight on the formation of these nanoparticles.

  8. Bandpass x-ray diode and x-ray multiplier detector

    DOE Patents [OSTI]

    Wang, C.L.

    1982-09-27T23:59:59.000Z

    An absorption-edge of an x-ray absorption filter and a quantum jump of a photocathode determine the bandpass characteristics of an x-ray diode detector. An anode, which collects the photoelectrons emitted by the photocathode, has enhanced amplification provided by photoelectron-multiplying means which include dynodes or a microchannel-plate electron-multiplier. Suppression of undesired high frequency response for a bandpass x-ray diode is provided by subtracting a signal representative of energies above the passband from a signal representative of the overall response of the bandpass diode.

  9. SLAC All Access: X-ray Microscope

    ScienceCinema (OSTI)

    Nelson, Johanna; Liu, Yijin

    2014-06-13T23:59:59.000Z

    SLAC physicists Johanna Nelson and Yijin Liu give a brief overview of the X-ray microscope at the Stanford Synchrotron Radiation Lightsource (SSRL) that is helping improve rechargeable-battery technology by letting researchers peek into the inner workings of batteries as they operate.

  10. Femtosecond X-ray protein nanocrystallography

    SciTech Connect (OSTI)

    Chapman, Henry N.; Fromme, Petra; Barty, Anton; White, Thomas A.; Kirian, Richard A.; Aquila, Andrew; Hunter, Mark S.; Schulz, Joachim; DePonte, Daniel P.; Weierstall, Uwe; Doak, R. Bruce; Maia, Filipe R. N. C.; Martin, Andrew V.; Schlichting, Ilme; Lomb, Lukas; Coppola, Nicola; Shoeman, Robert L.; Epp, Sascha W.; Hartmann, Robert; Rolles, Daniel; Rudenko, Artem; Foucar, Lutz; Kimmel, Nils; Weidenspointner, Georg; Holl, Peter; Liang, Mengning; Barthelmess, Miriam; Caleman, Carl; Boutet, Sebastien; Bogan, Michael J.; Krzywinski, Jacek; Bostedt, Christoph; Bajt, Sasa; Gumprecht, Lars; Rudek, Benedikt; Erk, Benjamin; Schmidt, Carlo; Homke, Andre; Reich, Christian; Pietschner, Daniel; Struder, Lothar; Hauser, Gunter; Gorke, Hubert; Ullrich, Joachim; Herrmann, Sven; Schaller, Gerhard; Schopper, Florian; Soltau, Heike; Kuhnel, Kai-Uwe; Messerschmidt, Marc; Bozek, John D.; Hau-Riege, Stefan P.; Frank, Matthias; Hampton, Christina Y.; Sierra, Raymond G.; Starodub, Dmitri; Williams, Garth J.; Hajdu, Janos; Timneanu, Nicusor; Seibert, M. Marvin; Andreasson, Jakob; Rocker, Andrea; Jonsson, Olof; Svenda, Martin; Stern, Stephan; Nass, Karol; Andritschke, Robert; Schroter, Claus-Dieter; Krasniqi, Faton; Bott, Mario; Schmidt, Kevin E.; Wang, Xiaoyu; Grotjohann, Ingo; Holton, James M.; Barends, Thomas R. M.; Neutze, Richard; Marchesini, Stefano; Fromme, Raimund; Schorb, Sebastian; Rupp, Daniela; Adolph, Marcus; Gorkhover, Tais; Andersson, Inger; Hirsemann, Helmut; Potdevin, Guillaume; Graafsma, Heinz; Nilsson, Bjorn; Spence, John C. H.

    2011-01-01T23:59:59.000Z

    X-ray crystallography provides the vast majority of macromolecular structures, but the success of the method relies on growing crystals of sufficient size. In conventional measurements, the necessary increase in X-ray dose to record data from crystals that are too small leads to extensive damage before a diffraction signal can be recorded. It is particularly challenging to obtain large, well-diffracting crystals of membrane proteins, for which fewer than 300 unique structures have been determined despite their importance in all living cells. Here we present a method for structure determination where single-crystal X-ray diffraction ‘snapshots’ are collected from a fully hydrated stream of nanocrystals using femtosecond pulses from a hard-X-ray free-electron laser, the Linac Coherent Light Source. We prove this concept with nanocrystals of photosystem I, one of the largest membrane protein complexes. More than 3,000,000 diffraction patterns were collected in this study, and a three-dimensional data set was assembled from individual photosystem I nanocrystals (~200?nm to 2??m in size). We mitigate the problem of radiation damage in crystallography by using pulses briefer than the timescale of most damage processes. This offers a new approach to structure determination of macromolecules that do not yield crystals of sufficient size for studies using conventional radiation sources or are particularly sensitive to radiation damage.

  11. Catalog of supersoft X-ray sources

    E-Print Network [OSTI]

    J. Greiner

    2000-05-11T23:59:59.000Z

    This catalog comprises an up-to-date (December 1999) list of luminous (>10^36 erg/s), binary supersoft X-ray sources. This electronic version (including the accompannying Web-pages) supersedes the printed version of Greiner (1996).

  12. A camera for coherent diffractive imaging and holography with a soft-X-ray free electron laser

    SciTech Connect (OSTI)

    Bajt, S; Chapman, H N; Spiller, E; Alameda, J; Woods, B; Frank, M; Bogan, M J; Barty, A; Boutet, S; Marchesini, S; Hau-Riege, S P; Hajdu, J; Shapiro, D

    2007-09-24T23:59:59.000Z

    We describe a camera to record coherent scattering patterns with a soft-X-ray free-electron laser. The camera consists of a laterally-graded multilayer mirror which reflects the diffraction pattern onto a CCD detector. The mirror acts as a bandpass filter both for wavelength and angle, which isolates the desired scattering pattern from non-sample scattering or incoherent emission from the sample. The mirror also solves the particular problem of the extreme intensity of the FEL pulses, which are focused to greater than 10{sup 14} W/cm{sup 2}. The strong undiffracted pulse passes through a hole in the mirror and propagates on to a beam dump at a distance behind the instrument rather than interacting with a beamstop placed near the CCD. The camera concept is extendable for the full range of the fundamental wavelength of the FLASH FEL (i.e. between 6 nm and 60 nm) and into the water window. We have fabricated and tested various multilayer mirrors for wavelengths of 32 nm, 16 nm, 13.5 nm, and 4.5 nm. At the shorter wavelengths mirror roughness must be minimized to reduce scattering from the mirror. We have recorded over 30,000 diffraction patterns at the FLASH free-electron laser with no observable mirror damage or degradation of performance.

  13. Transformation of x-ray server from a set of WWW-accessed programs into WWW-based library for remote calls from x-ray data analysis software.

    SciTech Connect (OSTI)

    Stepanov, S.; Biosciences Division

    2007-05-01T23:59:59.000Z

    X-ray Server [x-server.gmca.aps.anl.gov] is a public project providing a collection of online software tools for modeling data in the fields of surface X-ray scattering and grazing-incidence X-ray diffraction from thin solid films and multilayers with account for the effects of crystal lattice strains, magnetization and interface roughness. This paper reports on recent developments that are addressing numerous requests to expand the Server access beyond plain web browser sessions and facilitate batch processing, remote fitting and integration of Server programs into users' data analysis software.

  14. Do X-ray Binary Spectral State Transition Luminosities Vary?

    E-Print Network [OSTI]

    Thomas J. Maccarone

    2003-08-02T23:59:59.000Z

    We tabulate the luminosities of the soft-to-hard state transitions of all X-ray binaries for which there exist good X-ray flux measurements at the time of the transition, good distance estimates, and good mass estimates for the compact star. We show that the state transition luminosities are at about 1-4% of the Eddington rate, markedly smaller than those typically quoted in the literature, with a mean value of 2%. Only the black hole candidate GRO J~1655-40 and the neutron star systems Aql X-1 and 4U 1728-34 have measured state transition luminosities inconsistent with this value at the 1$\\sigma$ level. GRO J~1655-40, in particular, shows a state transition luminosity below the mean value for the other sources at the $4\\sigma$ level. This result, combined with the known inner disk inclination angle (the disk is nearly parallel to the line of sight) from GRO J~1655-40's relativistic jets suggest that the hard X-ray emitting region in GRO J~1655-40 can have a velocity of no more than about $\\beta=0.68$, with a most likely value of about $\\beta=0.52$, and a minimum speed of $\\beta=0.45$, assuming that the variations in state transition luminosities are solely due to relativistic beaming effects. The variance in the state transition luminosities suggests an emission region with a velocity of $\\sim0.2c$. The results are discussed in terms of different emission models for the low/hard state. We also discuss the implications for measuring the dimensionless viscosity parameter $\\alpha$. We also find that if its state transitions occur at typical luminosities, then GX 339-4 is likely to be at a distance of at least 7.6 kpc, much further than typically quoted estimates.

  15. Neutron Small Angle Scattering on Liquid Helium in the temperature Range 1.5-4.2 K

    E-Print Network [OSTI]

    Yu. M. Tsipenyuk; R. P. May

    2002-07-11T23:59:59.000Z

    The small angle neutron scattering from liquid helium at saturated vapour pressure in the temperature range from 1.5 to 4.2 K was measured with the instrument D22 of the ILL Grenoble at a wavelength of 4.6 angstrom. The zero angle cross section is monotonically decreasing with decreasing temperature and does not show any singularity at the lambda-point. On the other handd, we observe a change of the slope of the temperature dependence of thw second momentum of the pair correlation function at the lambda-point that reflects the transition of liquid to the superfluid state.

  16. From Nuclei to Micro-Structure in Colloidal Crystallization: Investigating Intermediate Length Scales by Small Angle Laser Light Scattering

    E-Print Network [OSTI]

    Richard Beyer; Markus Franke; Hans Joachim Schöpe; Eckhard Bartsch; Thomas Palberg

    2015-05-11T23:59:59.000Z

    Hard sphere suspensions are well recognized model systems of statistical physics and soft condensed matter. We here investigate the temporal evolution of the immediate environment of nucleating and growing crystals and/or their global scale distribution using time resolved Small Angle Light Scattering (SALS). Simultaneously performed Bragg scattering (BS) measurements provide an accurate temporal gauging of the sequence of events. We apply this approach to studies of re-crystallization in several different shear molten hard sphere and attractive hard sphere samples with the focus being on the diversity of observable signal shapes and their change in time. We demonstrate that depending on the preparation conditions different processes occur on length scales larger than the structural scale which significantly influence both the crystallization kinetics and the final micro-structure. By careful analysis of the SALS signal evolution and by comparing different suggestions for small angle signal shapes to our data we can for most cases identify the processes leading to the observed signals. These include phase contrast form factor scattering from depletion zones during formation and overlap as well as during gelation, amplitude contrast form factor scattering by more transparent crystals, and structure factor scattering from late stage inter-crystallite ordering. The large variety of different small angle signals thus in principle contains valuable information complementary to that gained from Bragg scattering or microscopy. Our comparison, however, also shows that further refinement and adaptation of the theoretical expressions to the sample specific boundary conditions is desired for a quantitative kinetic analysis of micro-structural evolution.

  17. Rise time measurement for ultrafast X-ray pulses

    DOE Patents [OSTI]

    Celliers, Peter M. (Berkeley, CA); Weber, Franz A. (Oakland, CA); Moon, Stephen J. (Tracy, CA)

    2005-04-05T23:59:59.000Z

    A pump-probe scheme measures the rise time of ultrafast x-ray pulses. Conventional high speed x-ray diagnostics (x-ray streak cameras, PIN diodes, diamond PCD devices) do not provide sufficient time resolution to resolve rise times of x-ray pulses on the order of 50 fs or less as they are being produced by modern fast x-ray sources. Here, we are describing a pump-probe technique that can be employed to measure events where detector resolution is insufficient to resolve the event. The scheme utilizes a diamond plate as an x-ray transducer and a p-polarized probe beam.

  18. Rise Time Measurement for Ultrafast X-Ray Pulses

    DOE Patents [OSTI]

    Celliers, Peter M.; Weber, Franz A.; Moon, Stephen J.

    2005-04-05T23:59:59.000Z

    A pump-probe scheme measures the rise time of ultrafast x-ray pulses. Conventional high speed x-ray diagnostics (x-ray streak cameras, PIN diodes, diamond PCD devices) do not provide sufficient time resolution to resolve rise times of x-ray pulses on the order of 50 fs or less as they are being produced by modern fast x-ray sources. Here, we are describing a pump-probe technique that can be employed to measure events where detector resolution is insufficient to resolve the event. The scheme utilizes a diamond plate as an x-ray transducer and a p-polarized probe beam.

  19. Active probing of cloud multiple scattering, optical depth, vertical thickness, and liquid water content using wide-angle imaging LIDAR.

    SciTech Connect (OSTI)

    Love, Steven P.; Davis, A. B. (Anthony B.); Rohde, C. A. (Charles A.); Tellier, L. L. (Larry L.); Ho, Cheng,

    2002-01-01T23:59:59.000Z

    At most optical wavelengths, laser light in a cloud lidar experiment is not absorbed but merely scattered out of the beam, eventually escaping the cloud via multiple scattering. There is much information available in this light scattered far from the input beam, information ignored by traditional 'on-beam' lidar. Monitoring these off-beam returns in a fully space- and time-resolved manner is the essence of our unique instrument, Wide Angle Imaging Lidar (WAIL). In effect, WAIL produces wide-field (60-degree full-angle) 'movies' of the scattering process and records the cloud's radiative Green functions. A direct data product of WAIL is the distribution of photon path lengths resulting from multiple scattering in the cloud. Following insights from diffusion theory, we can use the measured Green functions to infer the physical thickness and optical depth of the cloud layer, and, from there, estimate the volume-averaged liquid water content. WAIL is notable in that it is applicable to optically thick clouds, a regime in which traditional lidar is reduced to ceilometry. Here we present recent WAIL data oti various clouds and discuss the extension of WAIL to full diurnal monitoring by means of an ultra-narrow magneto-optic atomic line filter for daytime measurements.

  20. A grazing incidence x-ray streak camera for ultrafast, single-shot measurements

    SciTech Connect (OSTI)

    Feng, Jun; Engelhorn, K.; Cho, B.I.; Lee, H.J.; Greaves, M.; Weber, C.P.; Falcone, R.W.; Padmore, H. A.; Heimann, P.A.

    2010-02-18T23:59:59.000Z

    An ultrafast x-ray streak camera has been realized using a grazing incidence reflection photocathode. X-rays are incident on a gold photocathode at a grazing angle of 20 degree and photoemitted electrons are focused by a large aperture magnetic solenoid lens. The streak camera has high quantum efficiency, 600fs temporal resolution, and 6mm imaging length in the spectral direction. Its single shot capability eliminates temporal smearing due to sweep jitter, and allows recording of the ultrafast dynamics of samples that undergo non-reversible changes.

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

    SciTech Connect (OSTI)

    Guo, Jinghua

    2008-09-22T23:59:59.000Z

    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.

  2. Core and Valence Excitations in Resonant X-ray Spectroscopy using Restricted Excitation Window Time-dependent Density Functional Theory

    SciTech Connect (OSTI)

    Zhang, Yu; Biggs, Jason D.; Healion, Daniel; Govind, Niranjan; Mukamel, Shaul

    2012-11-21T23:59:59.000Z

    We report simulations of X-ray absorption near edge structure (XANES), resonant inelastic X-ray scattering (RIXS) and 1D stimulated X-ray Raman spectroscopy (SXRS) signals of cysteine at the oxygen, nitrogen and sulfur K and L2,3 edges. The simulated XANES signals from the restricted window time-dependent density functional theory (REW-TDDFT) and the static exchange (STEX) method are compared with experiments, showing that REW-TDDFT is more accurate and computationally less expensive than STEX. Simulated RIXS and 1D SXRS signals from REW-TDDFT give some insights on the correlation of different excitations in the molecule.

  3. X-RAY POINT-SOURCE POPULATIONS CONSTITUTING THE GALACTIC RIDGE X-RAY EMISSION

    SciTech Connect (OSTI)

    Morihana, Kumiko [Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)] [Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Tsujimoto, Masahiro; Ebisawa, Ken [Japan Aerospace Exploration Agency, Institute of Space and Astronautical Science, 3-1-1 Yoshino-dai, Chuo-ku, Sagamihara, Kanagawa 252-5210 (Japan)] [Japan Aerospace Exploration Agency, Institute of Space and Astronautical Science, 3-1-1 Yoshino-dai, Chuo-ku, Sagamihara, Kanagawa 252-5210 (Japan); Yoshida, Tessei, E-mail: morihana@crab.riken.jp [National Astronomical Observatory of Japan, 2-21-1, Osawa, Mitaka, Tokyo 181-8588 (Japan)] [National Astronomical Observatory of Japan, 2-21-1, Osawa, Mitaka, Tokyo 181-8588 (Japan)

    2013-03-20T23:59:59.000Z

    Apparently diffuse X-ray emission has been known to exist along the central quarter of the Galactic Plane since the beginning of X-ray astronomy; this is referred to as the Galactic Ridge X-ray emission (GRXE). Recent deep X-ray observations have shown that numerous X-ray point sources account for a large fraction of the GRXE in the hard band (2-8 keV). However, the nature of these sources is poorly understood. Using the deepest X-ray observations made in the Chandra bulge field, we present the result of a coherent photometric and spectroscopic analysis of individual X-ray point sources for the purpose of constraining their nature and deriving their fractional contributions to the hard-band continuum and Fe K line emission of the GRXE. Based on the X-ray color-color diagram, we divided the point sources into three groups: A (hard), B (soft and broad spectrum), and C (soft and peaked spectrum). The group A sources are further decomposed spectrally into thermal and non-thermal sources with different fractions in different flux ranges. From their X-ray properties, we speculate that the group A non-thermal sources are mostly active galactic nuclei and the thermal sources are mostly white dwarf (WD) binaries such as magnetic and non-magnetic cataclysmic variables (CVs), pre-CVs, and symbiotic stars, whereas the group B and C sources are X-ray active stars in flares and quiescence, respectively. In the log N-log S curve of the 2-8 keV band, the group A non-thermal sources are dominant above Almost-Equal-To 10{sup -14} erg cm{sup -2} s{sup -1}, which is gradually taken over by Galactic sources in the fainter flux ranges. The Fe K{alpha} emission is mostly from the group A thermal (WD binaries) and the group B (X-ray active stars) sources.

  4. Fundamental Parameters of Low Mass X-ray Binaries II: X-Ray Persistent Systems

    E-Print Network [OSTI]

    Jorge Casares; Phil Charles

    2005-06-24T23:59:59.000Z

    The determination of fundamental parameters in X-ray luminous (persistent) X-ray binaries has been classically hampered by the large optical luminosity of the accretion disc. New methods, based on irradiation of the donor star and burst oscillations, provide the opportunity to derive dynamical information and mass constraints in many persistent systems for the first time. These techniques are here reviewed and the latest results presented.

  5. Regularization approach for tomosynthesis X-ray inspection

    SciTech Connect (OSTI)

    Tigkos, Konstantinos; Hassler, Ulf; Holub, Wolfgang; Woerlein, Norbert; Rehak, Markus [Fraunhofer Development Center X-ray Technologies (EZRT), Dept. Application Specific Methods and Systems (AMS), Fraunhofer IIS, Flugplatzstraße 75, 90768 Fürth (Germany)

    2014-02-18T23:59:59.000Z

    X-ray inspection is intended to be used as an escalation technique for inspection of carbon fiber reinforced plastics (CFRP) in aerospace applications, especially in case of unclear indications from ultrasonic or other NDT modalities. Due to their large dimensions, most aerospace components cannot be scanned by conventional computed tomography. In such cases, X-ray Laminography may be applied, allowing a pseudo 3D slice-by-slice reconstruction of the sample with Tomosynthesis. However, due to the limited angle acquisition geometry, reconstruction artifacts arise, especially at surfaces parallel to the imaging plane. To regularize the Tomosynthesis approach, we propose an additional prescan of the object to detect outer sample surfaces. We recommend the use of contrasted markers which are temporarily attached to the sample surfaces. The depth position of the markers is then derived from that prescan. As long as the sample surface remains simple, few markers are required to fit the respective object surfaces. The knowledge about this surface may then be used to regularize the final Tomosynthesis reconstruction, performed with markerless projections. Eventually, it can also serve as prior information for an ART reconstruction or to register a CAD model of the sample. The presented work is carried out within the European FP7 project QUICOM. We demonstrate the proposed approach within a simulation study applying an acquisition geometry suited for CFRP part inspection. A practical verification of the approach is planned later in the project.

  6. Phonon dispersion of graphite by inelastic x-ray scattering * J. Maultzsch,1, E. Dobardzi,2 S. Reich,3 I. Milosevi,2 M. Damnjanovi,2 A. Bosak,4 M. Krisch,4 and

    E-Print Network [OSTI]

    Nabben, Reinhard

    , University of Belgrade, POB 368, 11011 Belgrade, Serbia 3Department of Materials Science and Engineering quality. It has been partly measured by inelastic neutron scattering INS , electron- energy loss, e.g., the crossing between the acoustic and optical bands near the M point or the energy

  7. Logical operations with single x-ray photons via dynamically-controlled nuclear resonances

    E-Print Network [OSTI]

    Jonas Gunst; Christoph H. Keitel; Adriana Pálffy

    2015-06-01T23:59:59.000Z

    The implementation of logical operations on polarization-encoded x-rays via resonant light-nucleus interactions is theoretically investigated. We show that by means of resonant scattering off nuclei and fast rotations of the nuclear hyperfine magnetic field to control the polarization of the output photon, single-qubit logical gates can be simulated. A second control qubit may be employed to trigger the magnetic field rotation, thus allowing several implementation choices for a controlled NOT gate for x-ray photons.

  8. The spectra of accretion discs in low-mass X-ray binaries

    E-Print Network [OSTI]

    R. R. Ross; A. C. Fabian

    1995-11-14T23:59:59.000Z

    We present self-consistent models for the radiative transfer in Shakura-Sunyaev accretion discs in bright low-mass X-ray binaries (LMXB). Our calculations include the full effects of incoherent Compton scattering and the vertical temperature structure within the disc, as well as the effects of Doppler blurring and gravitational redshift. We find that the observed X-ray spectra are well fit by exponentially cutoff power-law models. The difference between the observed total spectrum and our calculated disc spectrum should reveal the spectrum of the disc/neutron star boundary layer and other emitting regions considered to be present in LMXB.

  9. Theoretical standards in x-ray spectroscopies. Annual progress report, 1991--1992

    SciTech Connect (OSTI)

    Not Available

    1992-09-01T23:59:59.000Z

    We propose to extend our state-of-the-art, ab initio XAFS (X-ray absorption fine structure) codes, FEFF. Our current work has been highly successful in achieving accurate, user-friendly XAFS standards, exceeding the performance of both tabulated standards and other codes by a considerable margin. We now propose to add the capability to treat more complex materials. This includes multiple-scattering, polarization dependence, an approximate treatment of XANES (x-ray absorption near edge structure), and other improvements. We also plan to adapt FEFF to other spectroscopies, e.g. photoelectron diffraction (PD) and diffraction anomalous fine structure (DAFS).

  10. Maskelynite formation via solid-state transformation: Evidence of infrared and x-ray anisotropy

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Jaret, Steven J.; Ehm, Lars; Woerner, William R.; Phillips, Brian L.; Nekvasil, Hanna; Wright, Shawn P.; Glotch, Timothy D.

    2015-03-01T23:59:59.000Z

    We present optical microscopy, micro-Raman spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, high-energy X-ray total scattering experiments, and micro-Fourier transform infrared (micro-FTIR) spectroscopy on shocked labradorite from the Lonar Crater, India. We show that maskelynite of shock class 2 is structurally more similar to fused glass than to crystalline plagioclase. However, there are slight but significant differences – preservation of original pre-impact igneous zoning, anisotropy at Infrared wavelengths, X-ray anisotropy, and preservation of some intermediate range order – which are all consistent with a solid-state transformation formation of maskelynite.

  11. An x-ray setup to investigate the atomic order of confined liquids in slit geometry

    SciTech Connect (OSTI)

    Lippmann, M.; Ehnes, A.; Seeck, O. H. [Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg (Germany)] [Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg (Germany)

    2014-01-15T23:59:59.000Z

    A setup has been designed to investigate thin films of confined liquids with the use of X-ray scattering methods. The confinement is realized between the flat culets of a pair of diamonds by positioning and orienting the lower diamond with nanometer and micro radian accuracy. We routinely achieve gaps between 5 and 50 nm at culet diameters of 200 ?m. With this setup and a micro focused X-ray beam we have investigated the in-plane and the out-off-plane atomic order of benzene with atomic resolution.

  12. Mapping Local Strain in Thin Film/Substrate Systems using X-ray

    SciTech Connect (OSTI)

    Yan,H.; Murray, C.; Noyan, I.

    2007-01-01T23:59:59.000Z

    The authors report experimental data and modeling results for reflection microbeam x-ray topographs from a Si substrate strained by an overlying pseudomorphic SiGe film edge. The diffracted x-ray intensity from the Si substrate is strongly asymmetric as a function of distance from the film edge. A model of the diffracted intensity based on the classical Ewald-von Laue dynamical diffraction theory for an antisymmetric strain distribution indicates that the asymmetry in the diffracted beam profile is only due to the scattering process; individual intensity maxima in the intensity profile cannot be uniquely ascribed to individual features in the local strain distribution.

  13. An instrument for 3D x-ray nano-imaging

    SciTech Connect (OSTI)

    Holler, M.; Raabe, J.; Diaz, A.; Guizar-Sicairos, M.; Quitmann, C.; Menzel, A.; Bunk, O. [Paul Scherrer Institut, 5232 Villigen PSI (Switzerland)

    2012-07-15T23:59:59.000Z

    We present an instrument dedicated to 3D scanning x-ray microscopy, allowing a sample to be precisely scanned through a beam while the angle of x-ray incidence can be changed. The position of the sample is controlled with respect to the beam-defining optics by laser interferometry. The instrument achieves a position stability better than 10 nm standard deviation. The instrument performance is assessed using scanning x-ray diffraction microscopy and we demonstrate a resolution of 18 nm in 2D imaging of a lithographic test pattern while the beam was defined by a pinhole of 3 {mu}m in diameter. In 3D on a test object of copper interconnects of a microprocessor, a resolution of 53 nm is achieved.

  14. ASCA Discovery of Diffuse 6.4 keV Emission Near the Sgr C Complex: A New X-ray Reflection Nebula

    E-Print Network [OSTI]

    H. Murakami; K. Koyama; M. Tsujimoto; Y. Maeda; M. Sakano

    2000-12-14T23:59:59.000Z

    We present an ASCA discovery of diffuse hard X-ray emission from the Sgr C complex with its peak in the vicinity of the molecular cloud core. The X-ray spectrum is characterized by a strong 6.4-keV line and large absorption. These properties suggest that Sgr C is a new X-ray reflection nebula which emits fluorescent and scattered X-rays via irradiation from an external X-ray source. We found no adequately bright source in the immediate Sgr C vicinity to fully account for the fluorescence. The irradiating source may be the Galactic nucleus Sgr A*, which was brighter in the past than it is now as is suggested from observations of the first X-ray reflection nebula Sgr B2.

  15. Soft x-ray capabilities for investigating the strongly correlated...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    X-ray, aiming to understand their sciences for applying a new material. In particular, soft x-ray capabilities have been used to obtain microscopic-level understanding of the...

  16. Dawn of x-ray nonlinear optics | Stanford Synchrotron Radiation...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Dawn of x-ray nonlinear optics Wednesday, July 8, 2015 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Speaker: David Reis, PULSE Program Description X-ray free electron lasers...

  17. ALS X-Rays Shine a New Light on Catalysis

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    times science has used high-brilliance x-rays to look so closely at these reactions. Lead author Dr. David Mueller at the ALS using x-rays to characterize working fuel cells....

  18. A World's Top-10 X-ray Crystal Structure

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    A World's Top-10 X-ray Crystal Structure October 7, 2014 Bookmark and Share Philip Coppens An x-ray crystal structure solved by Philip Coppens has been chosen as one of the world's...

  19. Nanofabrication of Diffractive X-ray Optics for Synchrotrons...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    the soft x-ray range and down to 15 nm in the multi keV range. For use at x-ray free-electron laser (XFEL) sources, diffractive optics must be capable of withstanding extreme...

  20. High resolution x-ray lensless imaging by differential holographic encoding

    SciTech Connect (OSTI)

    Zhu, D.; Guizar-Sicairos, M.; Wu, B.; Scherz, A.; Acremann, Y.; Tylisczcak, T.; Fischer, P.; Friedenberger, N.; Ollefs, K.; Farle, M.; Fienup, J. R.; Stohr, J.

    2009-11-02T23:59:59.000Z

    X-ray free electron lasers (X-FEL{sub s}) will soon offer femtosecond pulses of laterally coherent x-rays with sufficient intensity to record single-shot coherent scattering patterns for nanoscale imaging. Pulse trains created by splitand-delay techniques even open the door for cinematography on unprecedented nanometer length and femtosecond time scales. A key to real space ultrafast motion pictures is fast and reliable inversion of the recorded reciprocal space scattering patterns. Here we for the first time demonstrate in the x-ray regime the power of a novel technique for lensless high resolution imaging, previously suggested by Guizar-Sicairos and Fienup termed holography with extended reference by autocorrelation linear differential operation, HERALD0. We have achieved superior resolution over conventional x-ray Fourier transform holography (FTH) without sacrifices in SNR or significant increase in algorithmic complexity. By combining images obtained from individual sharp features on an extended reference, we further show that the resolution can be even extended beyond the reference fabrication limits. Direct comparison to iterative phase retrieval image reconstruction and images recorded with stateof- the-art zone plate microscopes is presented. Our results demonstrate the power of HERALDO as a favorable candidate for robust inversion of single-shot coherent scattering patterns.

  1. Anomalous X-ray Diffraction Studies for Photovoltaic Applications

    SciTech Connect (OSTI)

    Not Available

    2011-06-22T23:59:59.000Z

    Anomalous X-ray Diffraction (AXRD) has become a useful technique in characterizing bulk and nanomaterials as it provides specific information about the crystal structure of materials. In this project we present the results of AXRD applied to materials for photovoltaic applications: ZnO loaded with Ga and ZnCo{sub 2}O{sub 4} spinel. The X-ray diffraction data collected for various energies were plotted in Origin software. The peaks were fitted using different functions including Pseudo Voigt, Gaussian, and Lorentzian. This fitting provided the integrated intensity data (peaks area values), which when plotted as a function of X-ray energies determined the material structure. For the first analyzed sample, Ga was not incorporated into the ZnO crystal structure. For the ZnCo{sub 2}O{sub 4} spinel Co was found in one or both tetrahedral and octahedral sites. The use of anomalous X-ray diffraction (AXRD) provides element and site specific information for the crystal structure of a material. This technique lets us correlate the structure to the electronic properties of the materials as it allows us to probe precise locations of cations in the spinel structure. What makes it possible is that in AXRD the diffraction pattern is measured at a number of energies near an X-ray absorption edge of an element of interest. The atomic scattering strength of an element varies near its absorption edge and hence the total intensity of the diffraction peak changes by changing the X-ray energy. Thus AXRD provides element specific structural information. This method can be applied to both crystalline and liquid materials. One of the advantages of AXRD in crystallography experiments is its sensitivity to neighboring elements in the periodic tables. This method is also sensitive to specific crystallographic phases and to a specific site in a phase. The main use of AXRD in this study is for transparent conductors (TCs) analysis. TCs are considered to be important materials because of their efficiency and low risk of environmental pollution. These materials are important to solar cells as a result of their remarkable combination of optical and electrical properties, including high electrical conductivity and high optical transparency in the spectrum of visible light. TCs provide a transparent window, which allows sunlight to pass through while also allowing electricity to conduct out of the cell. Spinel materials have the chemical form AB{sub 2}O{sub 4}, and are made of a face-centered cubic (FCC) lattice of oxygen anions and cations in specific interstitial sites. A normal spinel has all A cations on tetrahedral sites and B cations on octahedral sites. In contrast; an inverse spinel has the A and half of the B cations on octahedral sites and the other half of the B cations on tetrahedral sites; a mixed spinel lies between. In the spinel structure, 8 of 64 possible tetrahedral sites and 16 of 32 possible octahedral sites are filled. Normal spinels have particularly high conduction as the linear octahedral chains of B cations likely serve as conduction paths. In this paper we present how the data obtained with AXRD is used to analyze TCs properties as they apply to photovoltaic applications. One of the materials used for this analysis is zinc oxide. It has been loaded with 5% and 10% of Ga, which has an absorption edge of 10367 eV. The peak (100) was measured for the zinc oxide loaded with 10% Ga. In the case of 5% Ga, we measured peaks (100) and (101). With the information provided by the AXRD we can identify if Ga is being incorporated in the ZnO crystal structure. The analysis of 311 plane in the ZnCo{sub 2}O{sub 4} spinel shows if Co is in tetrahedral or octahedral site.

  2. X-ray tests of a two-dimensional stigmatic imaging scheme with variable magnifications

    SciTech Connect (OSTI)

    Lu, J., E-mail: jlu@pppl.gov [Key Laboratory of Optoelectronic Technology and System of Ministry of Education, Chongqing University, Chongqing 400030 (China); Bitter, M.; Hill, K. W.; Delgado-Aparicio, L. F.; Efthimion, P. C.; Pablant, N. A. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Beiersdorfer, P. [Physics Division, Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Caughey, T. A.; Brunner, J. [Inrad Optics, 181 Legrand Avenue, Northvale, New Jersey 07647 (United States)

    2014-11-15T23:59:59.000Z

    A two-dimensional stigmatic x-ray imaging scheme, consisting of two spherically bent crystals, one concave and one convex, was recently proposed [M. Bitter et al., Rev. Sci. Instrum. 83, 10E527 (2012)]. The Bragg angles and the radii of curvature of the two crystals of this imaging scheme are matched to eliminate the astigmatism and to satisfy the Bragg condition across both crystal surfaces for a given x-ray energy. In this paper, we consider more general configurations of this imaging scheme, which allow us to vary the magnification for a given pair of crystals and x-ray energy. The stigmatic imaging scheme has been validated for the first time by imaging x-rays generated by a micro-focus x-ray source with source size of 8.4 ?m validated by knife-edge measurements. Results are presented from imaging the tungsten L?1 emission at 8.3976 keV, using a convex Si-422 crystal and a concave Si-533 crystal with 2d-spacings of 2.21707 Å and 1.65635 Å and radii of curvature of 500 ± 1 mm and 823 ± 1 mm, respectively, showing a spatial resolution of 54.9 ?m. This imaging scheme is expected to be of interest for the two-dimensional imaging of laser produced plasmas.

  3. Beyond Chandra - the X-ray Surveyor

    E-Print Network [OSTI]

    Weisskopf, Martin C; Tananbaum, Harvey; Vikhlinin, Alexey

    2015-01-01T23:59:59.000Z

    Over the past 16 years, NASA's Chandra X-ray Observatory has provided an unparalleled means for exploring the universe with its half-arcsecond angular resolution. Chandra studies have deepened our understanding of galaxy clusters, active galactic nuclei, galaxies, supernova remnants, planets, and solar system objects addressing almost all areas of current interest in astronomy and astrophysics. As we look beyond Chandra, it is clear that comparable or even better angular resolution with greatly increased photon throughput is essential to address even more demanding science questions, such as the formation and subsequent growth of black hole seeds at very high redshift; the emergence of the first galaxy groups; and details of feedback over a large range of scales from galaxies to galaxy clusters. Recently, NASA Marshall Space Flight Center, together with the Smithsonian Astrophysical Observatory, has initiated a concept study for such a mission named the X-ray Surveyor. This study starts with a baseline payloa...

  4. X-ray mammography with synchrotron radiation

    SciTech Connect (OSTI)

    Burattini, E. (CNR and INFN-Laboratori Nazionali di Frascati, Frascati, Rome (Italy)); Gambaccini, M.; Marziani, M.; Rimondi, O. (Dipartimento di Fisica dell'Universita and Sezione INFN di Ferrara, Ferrara (Italy)); Indovina, P.L. (Dipartimento di Scienze Fisiche dell'Universita and Sezione INFN di Napoli, Naples (Italy)); Pocek, M.; Simonetti, G. (Istituto di Radiologia, Ospedale Sant'Eugenio, Universita di Tor Vergata, Rome (Italy)); Benassi, M.; Tirelli, C. (Istituto Nazionale del Cancro, Regina Elena, Rome (Italy)); Passariello, R. (Cattedra di Radiologia, Universita dell'Aquila, L'Aquila (Italy))

    1992-01-01T23:59:59.000Z

    For the first time in the literature, radiographs of breast phantoms were obtained using several monochromatic synchrotron radiation x-ray beams of selected energy in the range from 14 to 26 keV. In addition, after optimization of the photon energy as a function of the phantom thickness, several mammographs were obtained on surgically removed human breast specimens containing cancer nodules. Comparison between radiographs using a conventional x-ray unit and those obtained of the same specimens utilizing synchrotron monochromatic beams clearly shows that higher contrast and better resolution can be achieved with synchrotron radiation. These results demonstrate the possibility of obtaining radiographs of excised human breast tissue containing a greater amount of radiological information using synchrotron radiation.

  5. X-rays from Supernova Remnants

    E-Print Network [OSTI]

    B. Aschenbach

    2002-08-28T23:59:59.000Z

    A summary of X-ray observations of supernova remnants is presented including the explosion fragment A of the Vela SNR, Tycho, N132D, RX J0852-4622, the Crab Nebula and the 'bulls eye', and SN 1987A, high-lighting the progress made with Chandra and XMM-Newton and touching upon the questions which arise from these observations and which might inspire future research.

  6. Global SAXS Data Analysis for Multilamellar Vesicles: Evolution of the Scattering Density Profile (SDP) Model

    SciTech Connect (OSTI)

    Heftberger, Peter [University of Graz, Institute of Molecular Biosciences, Austria] [University of Graz, Institute of Molecular Biosciences, Austria; Kollmitzer, Benjamin [University of Graz, Institute of Molecular Biosciences, Austria] [University of Graz, Institute of Molecular Biosciences, Austria; Heberle, Frederick A [ORNL] [ORNL; Pan, Jianjun [ORNL] [ORNL; Rappolt, Michael [University of Leeds, UK] [University of Leeds, UK; Amenitsch, Heinz [Graz University of Technology] [Graz University of Technology; Kucerka, Norbert [Atomic Energy of Canada Limited (AECL), Canadian Neutron Beam Centre (CNBC) and Comenius University,] [Atomic Energy of Canada Limited (AECL), Canadian Neutron Beam Centre (CNBC) and Comenius University,; Katsaras, John [ORNL] [ORNL; Pabst, georg [University of Graz, Institute of Molecular Biosciences, Austria] [University of Graz, Institute of Molecular Biosciences, Austria

    2014-01-01T23:59:59.000Z

    The highly successful scattering density profile (SDP) model, used to jointly analyze small-angle X-ray and neutron scattering data from unilamellar vesicles, has been adapted for use with data from fully hydrated, liquid crystalline multilamellar vesicles (MLVs). Using a genetic algorithm, this new method is capable of providing high-resolution structural information, as well as determining bilayer elastic bending fluctuations from standalone X-ray data. Structural parameters such as bilayer thickness and area per lipid were determined for a series of saturated and unsaturated lipids, as well as binary mixtures with cholesterol. The results are in good agreement with previously reported SDP data, which used both neutron and X-ray data. The inclusion of deuterated and non-deuterated MLV neutron data in the analysis improved the lipid backbone information but did not improve, within experimental error, the structural data regarding bilayer thickness and area per lipid.

  7. Using X-ray free-electron lasers for probing of complex interaction dynamics of ultra-intense lasers with solid matter

    SciTech Connect (OSTI)

    Kluge, T., E-mail: t.kluge@hzdr.de; Huang, L. G.; Metzkes, J.; Bussmann, M. [Helmholtz-Zentrum Dresden-Rossendorf e.V., D-01328 Dresden (Germany)] [Helmholtz-Zentrum Dresden-Rossendorf e.V., D-01328 Dresden (Germany); Gutt, C. [Universität Siegen, D-57068 Siegen (Germany)] [Universität Siegen, D-57068 Siegen (Germany); Schramm, U.; Cowan, T. E. [Helmholtz-Zentrum Dresden-Rossendorf e.V., D-01328 Dresden (Germany) [Helmholtz-Zentrum Dresden-Rossendorf e.V., D-01328 Dresden (Germany); Technische Universität Dresden, D-01062 Dresden (Germany)

    2014-03-15T23:59:59.000Z

    We demonstrate the potential of X-ray free-electron lasers (XFEL) to advance the understanding of complex plasma dynamics by allowing for the first time nanometer and femtosecond resolution at the same time in plasma diagnostics. Plasma phenomena on such short timescales are of high relevance for many fields of physics, in particular in the ultra-intense ultra-short laser interaction with matter. Highly relevant yet only partially understood phenomena become directly accessible in experiment. These include relativistic laser absorption at solid targets, creation of energetic electrons and electron transport in warm dense matter, including the seeding and development of surface and beam instabilities, ambipolar expansion, shock formation, and dynamics at the surfaces or at buried layers. In this paper, we focus on XFEL plasma probing for high power laser matter interactions based on quantitative calculations using synthesized data and evaluate the feasibility of various imaging and scattering techniques with special focus on the small angle X-ray scattering technique.

  8. Accretion Disk Boundary Layers Around Neutron Stars: X-ray Production in Low-Mass X-ray Binaries

    E-Print Network [OSTI]

    Robert Popham; Rashid Sunyaev

    2000-04-03T23:59:59.000Z

    We present solutions for the structure of the boundary layer where the accretion disk meets the neutron star, which is expected to be the dominant source of high-energy radiation in low-mass X-ray binaries which contain weakly magnetized accreting neutron stars. We find that the main portion of the boundary layer gas is hot (> ~10^8 K), low in density, radially and vertically extended, and optically thick to scattering but optically thin to absorption. It will produce large X-ray luminosity by Comptonization. Energy is transported inward by viscosity, concentrating the energy dissipation in the dense, optically thick zone close to the stellar surface. We explore the dependence of the boundary layer structure on the mass accretion rate, the rotation rate of the star, the alpha viscosity parameter and the viscosity prescription. Radiation pressure is the dominant source of pressure in the boundary layer; the flux is close to the Eddington limiting flux even for luminosities well below (~0.01 times) L(Edd). At luminosities near L(Edd), the boundary layer expands radially, and has a radial extent larger than one stellar radius. Based on the temperatures and optical depths which characterize the boundary layer, we expect that Comptonization will produce a power-law spectrum at low source luminosities. At high luminosities, a Planckian spectrum will be produced in the dense region where most of the energy is released, and modified by Comptonization as the radiation propagates outward.

  9. The PG X-ray QSO sample: Links between the UV-X-ray Continuum and Emission Lines

    E-Print Network [OSTI]

    Beverley J. Wills; M. S. Brotherton; A. Laor; D. Wills; B. J. Wilkes; G. J. Ferland; Zhaohui Shang

    1999-05-07T23:59:59.000Z

    The UV to soft X-rays of luminous AGNs dominate their bolometric luminosity, driven by an accretion-powered dynamo at the center. These photons ionize the surrounding gas, thereby providing clues to fueling and exhaust. Two sets of important relationships - neither of them understood - link the continuum and gas properties. (i) Boroson & Green's `eigenvector 1' relationships: Steeper soft X-ray spectra are clearly related to narrower Hbeta emission and stronger optical Fe II emission from the BLR, and weaker [O III] 5007 from the NLR. We show that these relationships extend to UV spectra: narrower C III] 1909, stronger low ionization lines, larger Si III] 1892/C III] 1909 (a density indicator), weaker C IV 1549 but stronger higher-ionization N V 1240. We speculate that high accretion rates are linked to high columns of dense (1e10 - 1e11 cm-3), nitrogen-enhanced, low-ionization gas from nuclear starbursts. Linewidth, inverse Fe II-[O III] and inverse Fe II-C IV relationships hint at the geometrical arrangement of this gas. (ii) The Baldwin effect (inverse equivalent width - luminosity relationships): Our correlation analyses suggest that these are independent of the above eigenvector 1 relationships. The eigenvector 1 relationships can therefore be used in future work, to reduce scatter in the Baldwin relationships, perhaps fulfilling the dream of using the Baldwin effect for cosmological studies.

  10. Bright X-ray galaxies in SDSS filaments

    E-Print Network [OSTI]

    Tugay, A V

    2013-01-01T23:59:59.000Z

    Eighteen bright X-ray emitting galaxies were found in nearby filaments within SDSS region. Basic X-ray spectral parameters were estimated for these galaxies using power law model with photoelectric absorption. A close pair of X-ray galaxies was found.

  11. Femtosecond laser-electron x-ray source

    DOE Patents [OSTI]

    Hartemann, Frederic V.; Baldis, Hector A.; Barty, Chris P.; Gibson, David J.; Rupp, Bernhard

    2004-04-20T23:59:59.000Z

    A femtosecond laser-electron X-ray source. A high-brightness relativistic electron injector produces an electron beam pulse train. A system accelerates the electron beam pulse train. The femtosecond laser-electron X-ray source includes a high intra-cavity power, mode-locked laser and an x-ray optics system.

  12. ASCA Observations of the Sgr B2 Cloud: An X-Ray Reflection Nebula

    E-Print Network [OSTI]

    H. Murakami; K. Koyama; M. Sakano; M. Tsujimoto; Y. Maeda

    1999-08-20T23:59:59.000Z

    We present the ASCA results of imaging spectroscopy of the giant molecular cloud Sgr B2. The X-ray spectrum is found to be very peculiar; it exhibits a strong emission line at 6.4 keV, a low energy cutoff below about 4 keV and a pronounced edge-structure at 7.1 keV. The X-ray image is extended and its peak position is shifted from the core of the molecular cloud toward the Galactic center by about 1--2 arcminute. The X-ray spectrum and the morphology are well reproduced by a scenario that X-rays from an external source located in the Galactic center direction are scattered by the molecular cloud Sgr B2, and come into our line of sight. Thus Sgr B2 may be called an X-ray reflection nebula. Possible implications of the Galactic center activity related to this unique source are presented.

  13. Local structure of Rb{sub 2}Li{sub 4}(SeO{sub 4}){sub 3}{center_dot}2H{sub 2}O by the modeling of X-ray diffuse scattering - from average-structure to microdomain model

    SciTech Connect (OSTI)

    Komornicka, Dorota [Institute of Low Temperature and Structure Research, Polish Academy of Sciences, ul. Okolna 2, 50-420 Wroclaw (Poland); Wolcyrz, Marek, E-mail: m.wolcyrz@int.pan.wroc.pl [Institute of Low Temperature and Structure Research, Polish Academy of Sciences, ul. Okolna 2, 50-420 Wroclaw (Poland); Pietraszko, Adam [Institute of Low Temperature and Structure Research, Polish Academy of Sciences, ul. Okolna 2, 50-420 Wroclaw (Poland)

    2012-08-15T23:59:59.000Z

    Local structure of dirubidium tetralithium tris(selenate(VI)) dihydrate - Rb{sub 2}Li{sub 4}(SeO{sub 4}){sub 3}{center_dot} 2H{sub 2}O has been determined basing on the modeling of X-ray diffuse scattering. The origin of observed structured diffuse streaks is SeO{sub 4} tetrahedra switching between two alternative positions in two quasi-planar layers existing in each unit cell and formation of domains with specific SeO{sub 4} tetrahedra configuration locally fulfilling condition for C-centering in the 2a Multiplication-Sign 2b Multiplication-Sign c superstructure cell. The local structure solution is characterized by a uniform distribution of rather large domains (ca. thousand of unit cells) in two layers, but also monodomains can be taken into account. Inside a single domain SeO{sub 4} tetrahedra are ordered along ab-diagonal forming two-string ribbons. Inside the ribbons SeO{sub 4} and LiO{sub 4} tetrahedra share the oxygen corners, whereas ribbons are bound to each other by a net of hydrogen bonds and fastened by corner sharing SeO{sub 4} tetrahedra of the neighboring layers. - Graphical abstract: Experimental sections of the reciprocal space showing diffraction effects observed for RLSO. Bragg spots are visible on sections with integer indices (1 kl section - on the left), streaks - on sections with fractional ones (1.5 kl section - on the right). At the center: resulting local structure of the A package modeled as a microdomain: two-string ribbons of ordered oxygen-corners-sharing SeO{sub 4} and LiO{sub 4} terahedra extended along ab-diagonal are seen; ribbons are bound by hydrogen bonds (shown in pink); the multiplied 2a Multiplication-Sign 2b unit cell is shown. Highlights: Black-Right-Pointing-Pointer X-ray diffuse scattering in RLSO was registered and modeled. Black-Right-Pointing-Pointer The origin of diffuse streaks is SeO{sub 4} tetrahedra switching in two structure layers. Black-Right-Pointing-Pointer The local structure is characterized by a uniform distribution of microdomains. Black-Right-Pointing-Pointer Inside a single domain SeO{sub 4} tetrahedra are ordered along ab-diagonal forming ribbons. Black-Right-Pointing-Pointer The ribbons are bound to each other by a net of hydrogen bonds.

  14. Event Generation of Large-Angle Bhabha Scattering at LEP2 Energies

    E-Print Network [OSTI]

    A. B. Arbuzov

    1999-10-08T23:59:59.000Z

    LABSMC Monte Carlo event generator is used to simulate Bhabha scattering at high energies. Different sources of radiative corrections are considered. The resulting precision is discussed.

  15. The X-ray Halo of G21.5-0.9

    E-Print Network [OSTI]

    R. Bandiera; F. Bocchino

    2003-05-21T23:59:59.000Z

    The emission of the plerion G21.5-0.9 appears more extended in X rays than in radio. This is an unexpected result because it would imply that short-lived X-ray electrons may reach distances even larger than radio electrons. Applying an empirical relationship between dust scattering optical depth and photoelectric column density, the measured column density leads to a large optical depth at 1 keV, of about 1. Therefore we investigate the hypothesis that the detected halo be an effect of dust scattering, re-analyzing an Cal/PV XMM-Newton observation of G21.5-0.9 and critically examining it in terms of a dust scattering model. We also present a spectral analysis of a prominent extended feature in the northern sector of the halo.

  16. Proceedings of the workshop on X-ray computed microtomography

    SciTech Connect (OSTI)

    NONE

    1998-02-01T23:59:59.000Z

    This report consists of vugraphs from the nine presentations at the conference. Titles of the presentations are: CMT: Applications and Techniques; Computer Microtomography Using X-rays from Third Generation Synchrotron X-ray; Approaches to Soft-X-ray Nanotomography; Diffraction Enhanced Tomography; X-ray Computed Microtomography Applications at the NSLS; XCMT Applications in Forestry and Forest Products; 3DMA: Investigating Three Dimensional Pore Geometry from High Resolution Images; X-ray Computed Microtomography Studies of Volcanic Rock; and 3-D Visualization of Tomographic Volumes.

  17. Calibrating X-ray Imaging Devices for Accurate Intensity Measurement

    SciTech Connect (OSTI)

    Haugh, M. J.

    2011-07-28T23:59:59.000Z

    The purpose of the project presented is to develop methods to accurately calibrate X-ray imaging devices. The approach was to develop X-ray source systems suitable for this endeavor and to develop methods to calibrate solid state detectors to measure source intensity. NSTec X-ray sources used for the absolute calibration of cameras are described, as well as the method of calibrating the source by calibrating the detectors. The work resulted in calibration measurements for several types of X-ray cameras. X-ray camera calibration measured efficiency and efficiency variation over the CCD. Camera types calibrated include: CCD, CID, back thinned (back illuminated), front illuminated.

  18. Apparatus for monitoring X-ray beam alignment

    DOE Patents [OSTI]

    Steinmeyer, P.A.

    1991-10-08T23:59:59.000Z

    A self-contained, hand-held apparatus is provided for monitoring alignment of an X-ray beam in an instrument employing an X-ray source. The apparatus includes a transducer assembly containing a photoresistor for providing a range of electrical signals responsive to a range of X-ray beam intensities from the X-ray beam being aligned. A circuit, powered by a 7.5 VDC power supply and containing an audio frequency pulse generator whose frequency varies with the resistance of the photoresistor, is provided for generating a range of audible sounds. A portion of the audible range corresponds to low X-ray beam intensity. Another portion of the audible range corresponds to high X-ray beam intensity. The transducer assembly may include an a photoresistor, a thin layer of X-ray fluorescent material, and a filter layer transparent to X-rays but opaque to visible light. X-rays from the beam undergoing alignment penetrate the filter layer and excite the layer of fluorescent material. The light emitted from the fluorescent material alters the resistance of the photoresistor which is in the electrical circuit including the audio pulse generator and a speaker. In employing the apparatus, the X-ray beam is aligned to a complete alignment by adjusting the X-ray beam to produce an audible sound of the maximum frequency. 2 figures.

  19. Coded Aperture Imaging for Fluorescent X-rays-Biomedical Applications

    SciTech Connect (OSTI)

    Haboub, Abdel; MacDowell, Alastair; Marchesini, Stefano; Parkinson, Dilworth

    2013-06-01T23:59:59.000Z

    Employing a coded aperture pattern in front of a charge couple device pixilated detector (CCD) allows for imaging of fluorescent x-rays (6-25KeV) being emitted from samples irradiated with x-rays. Coded apertures encode the angular direction of x-rays and allow for a large Numerical Aperture x- ray imaging system. The algorithm to develop the self-supported coded aperture pattern of the Non Two Holes Touching (NTHT) pattern was developed. The algorithms to reconstruct the x-ray image from the encoded pattern recorded were developed by means of modeling and confirmed by experiments. Samples were irradiated by monochromatic synchrotron x-ray radiation, and fluorescent x-rays from several different test metal samples were imaged through the newly developed coded aperture imaging system. By choice of the exciting energy the different metals were speciated.

  20. HgMn Stars as apparent X-ray emitters

    E-Print Network [OSTI]

    Hubrig, S; Mathys, G

    1998-01-01T23:59:59.000Z

    In the ROSAT all-sky survey 11 HgMn stars were detected as soft X-ray emitters (Berghoefer, Schmitt & Cassinelli 1996). Prior to ROSAT, X-ray observations with the Einstein Observatory had suggested that stars in the spectral range B5-A7 are devoid of X-ray emission. Since there is no X-ray emitting mechanism available for these stars (also not for HgMn stars), the usual argument in the case of an X-ray detected star of this spectral type is the existence of an unseen low-mass companion which is responsible for the X-ray emission. The purpose of the present work is to use all available data for our sample of X-ray detected HgMn stars and conclude on the nature of possible companions.

  1. Hard X-ray polarimetry with Caliste, a high performance CdTe based imaging spectrometer

    E-Print Network [OSTI]

    S. Antier; P. Ferrando; O. Limousin; E. Caroli; R. M. Curado da Silva; C. Blondel; R. Chipaux; V. Honkimaki; B. Horeau; P. Laurent; J. M. Maia; A. Meuris; S. Del Sordo; J. B. Stephen

    2015-05-05T23:59:59.000Z

    Since the initial exploration of soft gamma-ray sky in the 60's, high-energy celestial sources have been mainly characterized through imaging, spectroscopy and timing analysis. Despite tremendous progress in the field, the radiation mechanisms at work in sources such as neutrons stars and black holes are still unclear. The polarization state of the radiation is an observational parameter which brings key additional information about the physical process. This is why most of the projects for the next generation of space missions covering the tens of keV to the MeV region require a polarization measurement capability. A key element enabling this capability is a detector system allowing the identification and characterization of Compton interactions as they are the main process at play. The hard X-ray imaging spectrometer module, developed in CEA with the generic name of Caliste module, is such a detector. In this paper, we present experimental results for two types of Caliste-256 modules, one based on a CdTe crystal, the other one on a CdZnTe crystal, which have been exposed to linearly polarized beams at the European Synchrotron Radiation Facility. These results, obtained at 200-300 keV, demonstrate their capability to give an accurate determination of the polarization parameters (polarization angle and fraction) of the incoming beam. Applying a selection to our data set, equivalent to select 90 degrees Compton scattered interactions in the detector plane, we find a modulation factor Q of 0.78. The polarization angle and fraction are derived with accuracies of approximately 1 degree and 5%. The modulation factor remains larger than 0.4 when essentially no selection is made at all on the data. These results prove that the Caliste-256 modules have performances allowing them to be excellent candidates as detectors with polarimetric capabilities, in particular for future space missions.

  2. Isotropic Detectable X-ray Counterparts to Gravitational Waves from Neutron Star Binary Mergers

    E-Print Network [OSTI]

    Shota Kisaka; Kunihito Ioka; Takashi Nakamura

    2015-06-05T23:59:59.000Z

    Neutron star binary mergers are strong sources of gravitational waves (GWs). Promising electromagnetic counterparts are short gamma-ray bursts (GRBs) but the emission is highly collimated. We propose that the scattering of the long-lasting plateau emission in short GRBs by the merger ejecta produces nearly isotropic emission for $\\sim 10^4$ s with flux $10^{-10}-10^{-13}$ erg cm$^{-2}$ s$^{-1}$ in X-ray. This is detectable by wide field X-ray detectors such as ISS-Lobster, eROSITA and WF-MAXI, which are desired by the infrared and optical follow-ups to localize and measure the distance to the host galaxy. The scattered X-rays obtain linear polarization, which correlates with the jet direction, X-ray luminosity and GW polarizations. The activity of plateau emission is also a natural energy source of a macronova (or kilonova) detected in short GRB 130603B without the $r$-process radioactivity.

  3. Isotropic Detectable X-ray Counterparts to Gravitational Waves from Neutron Star Binary Mergers

    E-Print Network [OSTI]

    Kisaka, Shota; Nakamura, Takashi

    2015-01-01T23:59:59.000Z

    Neutron star binary mergers are strong sources of gravitational waves (GWs). Promising electromagnetic counterparts are short gamma-ray bursts (GRBs) but the emission is highly collimated. We propose that the scattering of the long-lasting plateau emission in short GRBs by the merger ejecta produces nearly isotropic emission for $\\sim 10^4$ s with flux $10^{-10}-10^{-13}$ erg cm$^{-2}$ s$^{-1}$ in X-ray. This is detectable by wide field X-ray detectors such as ISS-Lobster, eROSITA and WF-MAXI, which are desired by the infrared and optical follow-ups to localize and measure the distance to the host galaxy. The scattered X-rays obtain linear polarization, which correlates with the jet direction, X-ray luminosity and GW polarizations. The activity of plateau emission is also a natural energy source of a macronova (or kilonova) detected in short GRB 130603B without the $r$-process radioactivity.

  4. X-ray emission properties of galaxies in Abell 3128

    E-Print Network [OSTI]

    Russell J. Smith

    2003-07-15T23:59:59.000Z

    We use archival Chandra X-ray Observatory data to investigate X-ray emission from early-type galaxies in the rich z=0.06 cluster Abell 3128. By combining the X-ray count-rates from an input list of optically-selected galaxies, we obtain a statistical detection of X-ray flux, unbiased by X-ray selection limits. Using 87 galaxies with reliable Chandra data, X-ray emission is detected for galaxies down to M_B ~ -19.0, with only an upper limit determined for galaxies at M_B ~ -18.3. The ratio of X-ray to optical luminosities is consistent with recent determinations of the low-mass X-ray binary content of nearby elliptical galaxies. Taken individually, in contrast, we detect significant (3sigma) flux for only six galaxies. Of these, one is a foreground galaxy, while two are optically-faint galaxies with X-ray hardness ratios characteristic of active galactic nuclei. The remaining three detected galaxies are amongst the optically-brightest cluster members, and have softer X-ray spectra. Their X-ray flux is higher than that expected from X-ray binaries, by a factor 2-10; the excess suggests these galaxies have retained their hot gaseous haloes. The source with the highest L_X / L_B ratio is of unusual optical morphology with prominent sharp-edged shells. Notwithstanding these few exceptions, the cluster population overall exhibits X-ray properties consistent with their emission being dominated by X-ray binaries. We conclude that in rich cluster environments, interaction with the ambient intra-cluster medium acts to strip most galaxies of their hot halo gas.

  5. 2011 X-Ray Science Gordon Research Conference (August 7-12, 2011, Colby, College. Waterville, ME)

    SciTech Connect (OSTI)

    Gregory Stephenson

    2011-08-12T23:59:59.000Z

    The 2011 Gordon Research Conference on X-ray Science will feature forefront x-ray-based science enabled by the rapid improvements in synchrotron and x-ray laser sources. Across the world, x-ray sources are playing an increasingly important role in physics, materials, chemistry, and biology, expanding into ever broadening areas of science and engineering. With the first hard x-ray free electron laser source beginning operation and with other advanced x-ray sources operational and planned, it is a very exciting and pivotal time for exchange ideas about the future of x-ray science and applications. The Conference will provide the forum for this interaction. An international cast of speakers will illuminate sessions on ultrafast science, coherence, imaging, in situ studies, extreme conditions, new developments in optics, sources, and detectors, inelastic scattering, nanoscience, life science, and energy sciences. The Conference will bring together investigators at the forefront of these areas, and will provide a venue for young scientists entering a career in x-ray research to present their research in poster format, hold discussions in a friendly setting, and exchange ideas with leaders in the field. Some poster presenters will be selected for short talks. The collegial atmosphere of this Conference, with ample time for discussion as well as opportunities for informal gatherings in the afternoons and evenings, will provide an avenue for scientists from different disciplines to exchange ideas about forefront x-ray techniques and will promote cross-fertilization between the various research areas represented.

  6. Scanning Transmission X-ray Microscopy: Applications in Atmospheric Aerosol Research

    E-Print Network [OSTI]

    Moffet, Ryan C.

    2011-01-01T23:59:59.000Z

    2-ID-B intermediate-energy scanning X-ray microscope at theW. D. , Morrison, G. R. et al. Scanning transmission X-rayX-ray spectromicroscopy with the scanning transmission X-ray

  7. Study of multilayered SiGe semiconductor structures by X-ray diffractometry, grazing-incidence X-ray reflectometry, and secondary-ion mass spectrometry

    SciTech Connect (OSTI)

    Yunin, P. A., E-mail: yunin@ipmras.ru; Drozdov, Yu. N.; Drozdov, M. N.; Korolev, S. A.; Lobanov, D. N. [Institute for Physics of Microstructures (Russian Federation)

    2013-12-15T23:59:59.000Z

    In this publication, we report the results of studying a multilayerd nonperiodic SiGe/Si structure by the methods of X-ray diffractometry, grazing-angle X-ray reflectometry, and secondary-ion mass spectrometry (SIMS). Special attention is paid to the processing of the component distribution profile using the SIMS method and to consideration of the most significant experimental distortions introduced by this method. A method for processing the measured composition distribution profile with subsequent consideration of the influence of matrix effects, variation in the etching rate, and remnants of ion sputtering is suggested. The results of such processing are compared with a structure model obtained upon combined analysis of X-ray diffractometry and grazing-angle reflectometry data. Good agreement between the results is established. It is shown that the combined use of independent techniques makes it possible to improve the methods of secondary-ion mass spectrometry and grazing-incidence reflectometry as applied to an analysis of multilayered heteroepitaxial structures (to increase the accuracy and informativity of these methods)

  8. X-ray generation using carbon nanotubes

    E-Print Network [OSTI]

    Parmee, Richard J.; Collins, Clare M.; Milne, William I.; Cole, Matthew T.

    2015-01-06T23:59:59.000Z

    of these sys- tems are illustrated in Figure 2(b) also outlines the principle mode of operation. Here, sealed in an inexpensive and eas- ily fabricated evacuated glass or ceramic envelope, the elec- trons are liberated from a metallic filament, often made... - ment of CNT-based FE sources is provided in [152]. Here we provide a condensed review of the progress, as it pertains to X-ray sources, since then. CNTs have some of the highest attainable aspect ratios, high thermal conductivity, low chemical...

  9. The BMW X-ray Cluster Survey

    E-Print Network [OSTI]

    Alberto Moretti; Luigi Guzzo; Sergio Campana; Stefano Covino; Davide Lazzati; Marcella Longhetti; Emilio Molinari; Maria Rosa Panzera; Gianpiero Tagliaferri; Ian Dell'Antonio

    2001-03-21T23:59:59.000Z

    We describe the main features of the BMW survey of serendipitous X-ray clusters, based on the still unexploited ROSAT-HRI archival observations. The sky coverage, surface density and first deep optical CCD images of the candidates indicate that this sample can represent an excellent complement to the existing PSPC deep cluster surveys and will provide us with a fully independent probe of the evolution of the cluster abundance, in addition to significantly increasing the number of clusters known at z>0.6.

  10. The BMW X-ray Cluster Survey

    E-Print Network [OSTI]

    Moretti, A; Campana, S; Covino, S; Lazzati, D; Longhetti, M; Molinari, E; Panzera, M R; Tagliaferri, G; Dell'Antonio, I P; Moretti, Alberto; Guzzo, Luigi; Campana, Sergio; Covino, Stefano; Lazzati, Davide; Longhetti, Marcella; Molinari, Emilio; Panzera, Maria Rosa; Tagliaferri, Gianpiero; Antonio, Ian Dell'

    2001-01-01T23:59:59.000Z

    We describe the main features of the BMW survey of serendipitous X-ray clusters, based on the still unexploited ROSAT-HRI archival observations. The sky coverage, surface density and first deep optical CCD images of the candidates indicate that this sample can represent an excellent complement to the existing PSPC deep cluster surveys and will provide us with a fully independent probe of the evolution of the cluster abundance, in addition to significantly increasing the number of clusters known at z>0.6.

  11. Lensless X-Ray Imaging in Reflection

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated Codes |Is Your HomeLatest News ReleasesDepartmentLendingX-Ray Imaging in

  12. Lensless X-Ray Imaging in Reflection

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated Codes |Is Your HomeLatest News ReleasesDepartmentLendingX-Ray Imaging

  13. Lensless X-Ray Imaging in Reflection

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated Codes |Is Your HomeLatest News ReleasesDepartmentLendingX-Ray

  14. Lensless X-Ray Imaging in Reflection

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12electron 9 5 -ofLearningLensless ImagingLensless X-Ray

  15. SMB, X-ray Absorption Spectroscopy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiation Protection245C Unlimited ReleaseWelcome to theAbsorption Spectroscopy X-ray

  16. Small-Angle Neutron Scattering study of solubilization of tributyl phosphate in aqueous solutions of L64 Pluronic triblock copolymers

    E-Print Network [OSTI]

    Jeremy Causse; Julian Oberdisse; Jacques Jestin; Serge Lagerge

    2010-12-04T23:59:59.000Z

    We have studied the solubilization behaviour of tributylphosphate (TBP) in aqueous solutions of L64-Pluronics, using light and small angle neutron scattering (SANS). Varying the temperature and the oil-content, the system presents a non trivial phase behaviour. In particular, at 308K, a first solubilization followed by an emulsification failure and a resolubilization is found. We have measured the microstructure by SANS and characterized the microemulsion droplet core-size, corona-thickness, polydispersity, and interactions. It is shown that at low oil content, the system is made of small swollen micelles. After the phase separation, the resolubilization is carried by larger oil droplets decorated by copolymer. From specific surface measurements at large angles, a surprising change in surfactant conformation is found to accompany this morphological evolution which is also supported by previous results obtained from 1H NMR experiments. In independent measurements, our structural modelling is confirmed using contrast-variation SANS.

  17. angle quasi-elastic scattering: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    hadronic (piN) states. An estimate of the beam-normal single-spin asymmetry for the scattering from the neutron is made using a quasi-static deuterium approximation, and is...

  18. An effective long-range attraction between protein molecules in solutions studied by small angle neutron scattering

    E-Print Network [OSTI]

    Yun Liu; Emiliano Fratini; Piero Baglioni; Wei-Ren Chen; Sow-Hsin Chen

    2005-08-05T23:59:59.000Z

    Small angle neutron scattering intensity distributions taken from cytochrome C and lysozyme protein solutions show a rising intensity at very small wave vector, Q, which can be interpreted in terms of the presence of a weak long-range attraction between protein molecules. This interaction has a range several times that of the diameter of the protein molecule, much greater than the range of the screened electrostatic repulsion. We show evidence that this long-range attraction is closely related to the type of anion present and ion concentration in the solution.

  19. Investigation of coercivity mechanism in hot deformed Nd-Fe-B permanent magnets by small-angle neutron scattering

    SciTech Connect (OSTI)

    Yano, M., E-mail: masao-yano-aa@mail.toyota.co.jp; Manabe, A.; Shoji, T.; Kato, A. [Advanced Material Engineering Division, Toyota Motor Corporation, Susono 410-1193 (Japan); Ono, K. [High Energy Accelerator Research Organization (KEK), Tsukuba 305-0801 (Japan); Harada, M. [Toyota Central R and D Labs, Inc., Aichi 480-1192 (Japan); Kohlbrecher, J. [Laboratory for Neutron Scattering, Paul Scherrer Institut, 5232 Villigen PSI (Switzerland)

    2014-05-07T23:59:59.000Z

    The magnetic reversal behaviors of single domain sized Nd-Fe-B permanent magnets, with and without isolation between the Nd{sub 2}Fe{sub 14}B grains, was clarified using small-angle neutron scattering (SANS). The SANS patterns obtained arose from changes in the magnetic domains and were analyzed using the Teubner–Stray model, a phenomenological correlation length model, to quantify the periodicity and morphology of the magnetic domains. The results indicated that the magnetic reversal evolved with the magnetic domains that had similar sized grains. The grain isolation enabled us to realize the reversals of single domains.

  20. Atomic holography with electrons and x-rays: Theoretical and experimental studies

    SciTech Connect (OSTI)

    Len, P M [Univ. of California, Davis, CA (United States). Dept. of Physics

    1997-06-01T23:59:59.000Z

    Gabor first proposed holography in 1948 as a means to experimentally record the amplitude and phase of scattered wavefronts, relative to a direct unscattered wave, and to use such a {open_quotes}hologram{close_quotes} to directly image atomic structure. But imaging at atomic resolution has not yet been possible in the way he proposed. Much more recently, Szoeke in 1986 noted that photoexcited atoms can emit photoelectron of fluorescent x-ray wavefronts that are scattered by neighboring atoms, thus yielding the direct and scattered wavefronts as detected in the far field that can then be interpreted as holographic in nature. By now, several algorithms for directly reconstructing three-dimensional atomic images from electron holograms have been proposed (e.g. by Barton) and successfully tested against experiment and theory. Very recently, Tegze and Faigel, and Grog et al. have recorded experimental x-ray fluorescence holograms, and these are found to yield atomic images that are more free of the kinds of aberrations caused by the non-ideal emission or scattering of electrons. The basic principles of these holographic atomic imaging methods are reviewed, including illustrative applications of the reconstruction algorithms to both theoretical and experimental electron and x-ray holograms. The author also discusses the prospects and limitations of these newly emerging atomic structural probes.

  1. The variability properties of X-ray steep and X-ray flat quasars

    E-Print Network [OSTI]

    Fabrizio Fiore; Ari Laor; Martin Elvis; Fabrizio Nicastro; Emanuele Giallongo

    1998-03-20T23:59:59.000Z

    We have studied the variability of 6 low redshift, radio quiet `PG' quasars on three timescales (days, weeks, and months) using the ROSAT HRI. The quasars were chosen to lie at the two extreme ends of the ROSAT PSPC spectral index distribution and hence of the H$\\beta$ FWHM distribution. The observation strategy has been carefully designed to provide even sampling on these three basic timescales and to provide a uniform sampling among the quasars We have found clear evidence that the X-ray steep, narrow H_beta, quasars systematically show larger amplitude variations than the X-ray flat broad H_beta quasars on timescales from 2 days to 20 days. On longer timescales we do not find significant differences between steep and flat quasars, although the statistics are poorer. We suggest that the above correlation between variability properties and spectral steepness can be explained in a scenario in which the X-ray steep, narrow line objects are in a higher L/L_Edd state with respect to the X-ray flat, broad line objects. We evaluated the power spectrum of PG1440+356 (the brigthest quasar in our sample) between 2E-7 and 1E-3 Hz, where it goes into the noise. The power spectrum is roughly consistent with a 1/f law between 1E-3 and 2E-6 Hz. Below this frequency it flattens significantly.

  2. Time-, frequency-, and wavevector-resolved x-ray diffraction from single molecules

    SciTech Connect (OSTI)

    Bennett, Kochise, E-mail: kcbennet@uci.edu; Biggs, Jason D.; Zhang, Yu; Dorfman, Konstantin E.; Mukamel, Shaul, E-mail: smukamel@uci.edu [University of California, Irvine, California 92697-2025 (United States)

    2014-05-28T23:59:59.000Z

    Using a quantum electrodynamic framework, we calculate the off-resonant scattering of a broadband X-ray pulse from a sample initially prepared in an arbitrary superposition of electronic states. The signal consists of single-particle (incoherent) and two-particle (coherent) contributions that carry different particle form factors that involve different material transitions. Single-molecule experiments involving incoherent scattering are more influenced by inelastic processes compared to bulk measurements. The conditions under which the technique directly measures charge densities (and can be considered as diffraction) as opposed to correlation functions of the charge-density are specified. The results are illustrated with time- and wavevector-resolved signals from a single amino acid molecule (cysteine) following an impulsive excitation by a stimulated X-ray Raman process resonant with the sulfur K-edge. Our theory and simulations can guide future experimental studies on the structures of nano-particles and proteins.

  3. Software for reflectivity calculations of x-ray mirrors. Revision 1

    SciTech Connect (OSTI)

    Auerbach, J.M.; Tirsell, K.G.

    1984-11-28T23:59:59.000Z

    With VAX software and the data libraries of Henke and Biggs-Lighthill, we have created a library of atomic scattering factors f/sub 1/ and f/sub 2/ in the energy range 0.1 keV to 10.0 keV. Scattering factor values for the elements Z = 1 to Z = 94 and in the above energy range are stored in a keyed access library (key = element symbol). This library allows one to calculate reflectivity rapidly and fold it with other components in an x-ray detector channel. Additional software allows the library data to be easily extended to higher energies. Applications have so far included KB x-ray microscopes and low energy spectrometers with mirror channels.

  4. Soft x-ray reduction camera for submicron lithography

    DOE Patents [OSTI]

    Hawryluk, Andrew M. (2708 Rembrandt Pl., Modesto, CA 95356); Seppala, Lynn G. (7911 Mines Rd., Livermore, CA 94550)

    1991-01-01T23:59:59.000Z

    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.

  5. Fabrication process for a gradient index x-ray lens

    DOE Patents [OSTI]

    Bionta, Richard M. (Livermore, CA); Makowiecki, Daniel M. (Livermore, CA); Skulina, Kenneth M. (Livermore, CA)

    1995-01-01T23:59:59.000Z

    A process for fabricating high efficiency x-ray lenses that operate in the 0.5-4.0 keV region suitable for use in biological imaging, surface science, and x-ray lithography of integrated circuits. The gradient index x-ray optics fabrication process broadly involves co-sputtering multi-layers of film on a wire, followed by slicing and mounting on block, and then ion beam thinning to a thickness determined by periodic testing for efficiency. The process enables the fabrication of transmissive gradient index x-ray optics for the 0.5-4.0 keV energy range. This process allows the fabrication of optical elements for the next generation of imaging and x-ray lithography instruments m the soft x-ray region.

  6. Fabrication process for a gradient index x-ray lens

    DOE Patents [OSTI]

    Bionta, R.M.; Makowiecki, D.M.; Skulina, K.M.

    1995-01-17T23:59:59.000Z

    A process is disclosed for fabricating high efficiency x-ray lenses that operate in the 0.5-4.0 keV region suitable for use in biological imaging, surface science, and x-ray lithography of integrated circuits. The gradient index x-ray optics fabrication process broadly involves co-sputtering multi-layers of film on a wire, followed by slicing and mounting on block, and then ion beam thinning to a thickness determined by periodic testing for efficiency. The process enables the fabrication of transmissive gradient index x-ray optics for the 0.5-4.0 keV energy range. This process allows the fabrication of optical elements for the next generation of imaging and x-ray lithography instruments in the soft x-ray region. 13 figures.

  7. Density gradient free electron collisionally excited X-ray laser

    DOE Patents [OSTI]

    Campbell, Edward M. (Pleasanton, CA); Rosen, Mordecai D. (Berkeley, CA)

    1989-01-01T23:59:59.000Z

    An operational X-ray laser (30) is provided that amplifies 3p-3s transition X-ray radiation along an approximately linear path. The X-ray laser (30) is driven by a high power optical laser. The driving line focused optical laser beam (32) illuminates a free-standing thin foil (34) that may be associated with a substrate (36) for improved structural integrity. This illumination produces a generally cylindrically shaped plasma having an essentially uniform electron density and temperature, that exists over a long period of time, and provides the X-ray laser gain medium. The X-ray laser (30) may be driven by more than one optical laser beam (32, 44). The X-ray laser (30) has been successfully demonstrated to function in a series of experimental tests.

  8. Soft x-ray reduction camera for submicron lithography

    DOE Patents [OSTI]

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

    1991-03-26T23:59:59.000Z

    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.

  9. Density gradient free electron collisionally excited x-ray laser

    DOE Patents [OSTI]

    Campbell, E.M.; Rosen, M.D.

    1984-11-29T23:59:59.000Z

    An operational x-ray laser is provided that amplifies 3p-3s transition x-ray radiation along an approximately linear path. The x-ray laser is driven by a high power optical laser. The driving line focused optical laser beam illuminates a free-standing thin foil that may be associated with a substrate for improved structural integrity. This illumination produces a generally cylindrically shaped plasma having an essentially uniform electron density and temperature, that exists over a long period of time, and provides the x-ray laser gain medium. The x-ray laser may be driven by more than one optical laser beam. The x-ray laser has been successfully demonstrated to function in a series of experimental tests.

  10. Parameterised Electromagnetic Scattering Solutions for a Range of Incident Wave Angles

    E-Print Network [OSTI]

    Peraire, Jaime

    reduction in the computational costs. Reduced--order approximations operate in two stages. In an initial off of these computations are stored. In an on­line stage, specified outputs of interest are computed at low cost for new in determining the scattering width distribution for a new design. Computational methods can provide assistance

  11. Beam Normal Single Spin Asymmetry in Forward Angle Inelastic Electron-Proton Scattering using the Q-Weak Apparatus

    SciTech Connect (OSTI)

    Nuruzzaman, nfn [Thomas Jefferson National Accelerator Facility and Hampton University

    2014-12-01T23:59:59.000Z

    The Q-weak experiment in Hall-C at the Thomas Jefferson National Accelerator Facility has made the first direct measurement of the weak charge of the proton through the precision measurement of the parity-violating asymmetry in elastic electron-proton scattering at low momentum transfer. There is also a parity conserving Beam Normal Single Spin Asymmetry or transverse asymmetry (B_n) on H_2 with a sin(phi)-like dependence due to two-photon exchange. If the size of elastic B_n is a few ppm, then a few percent residual transverse polarization in the beam, combined with small broken azimuthal symmetries in the detector, would require a few ppb correction to the Q-weak data. As part of a program of B_n background studies, we made the first measurement of B_n in the N-to-Delta(1232) transition using the Q-weak apparatus. The final transverse asymmetry, corrected for backgrounds and beam polarization, was found to be B_n = 42.82 ± 2.45 (stat) ± 16.07 (sys) ppm at beam energy E_beam = 1.155 GeV, scattering angle theta = 8.3 deg, and missing mass W = 1.2 GeV. B_n from electron-nucleon scattering is a unique tool to study the gamma^* Delta Delta form factors, and this measurement will help to improve the theoretical models on beam normal single spin asymmetry and thereby our understanding of the doubly virtual Compton scattering process. To help correct false asymmetries from beam noise, a beam modulation system was implemented to induce small position, angle, and energy changes at the target to characterize detector response to the beam jitter. Two air-core dipoles separated by ~10 m were pulsed at a time to produce position and angle changes at the target, for virtually any tune of the beamline. The beam energy was modulated using an SRF cavity. The hardware and associated control instrumentation will be described in this dissertation. Preliminary detector sensitivities were extracted which helped to reduce the width of the measured asymmetry. The beam modulation system has also proven valuable for tracking changes in the beamline optics, such as dispersion at the target.

  12. Cone beam x-ray luminescence computed tomography: A feasibility study

    SciTech Connect (OSTI)

    Chen Dongmei; Zhu Shouping; Yi Huangjian; Zhang Xianghan; Chen Duofang; Liang Jimin [School of Life Sciences and Technology, Xidian University, Xi'an 710071 (China); Tian Jie [School of Life Sciences and Technology, Xidian University, Xi'an 710071 (China); Medical Image Processing Group, Institute of Automation, Chinese Academy of Sciences, Beijing 100190 (China)

    2013-03-15T23:59:59.000Z

    Purpose: The appearance of x-ray luminescence computed tomography (XLCT) opens new possibilities to perform molecular imaging by x ray. In the previous XLCT system, the sample was irradiated by a sequence of narrow x-ray beams and the x-ray luminescence was measured by a highly sensitive charge coupled device (CCD) camera. This resulted in a relatively long sampling time and relatively low utilization of the x-ray beam. In this paper, a novel cone beam x-ray luminescence computed tomography strategy is proposed, which can fully utilize the x-ray dose and shorten the scanning time. The imaging model and reconstruction method are described. The validity of the imaging strategy has been studied in this paper. Methods: In the cone beam XLCT system, the cone beam x ray was adopted to illuminate the sample and a highly sensitive CCD camera was utilized to acquire luminescent photons emitted from the sample. Photons scattering in biological tissues makes it an ill-posed problem to reconstruct the 3D distribution of the x-ray luminescent sample in the cone beam XLCT. In order to overcome this issue, the authors used the diffusion approximation model to describe the photon propagation in tissues, and employed the sparse regularization method for reconstruction. An incomplete variables truncated conjugate gradient method and permissible region strategy were used for reconstruction. Meanwhile, traditional x-ray CT imaging could also be performed in this system. The x-ray attenuation effect has been considered in their imaging model, which is helpful in improving the reconstruction accuracy. Results: First, simulation experiments with cylinder phantoms were carried out to illustrate the validity of the proposed compensated method. The experimental results showed that the location error of the compensated algorithm was smaller than that of the uncompensated method. The permissible region strategy was applied and reduced the reconstruction error to less than 2 mm. The robustness and stability were then evaluated from different view numbers, different regularization parameters, different measurement noise levels, and optical parameters mismatch. The reconstruction results showed that the settings had a small effect on the reconstruction. The nonhomogeneous phantom simulation was also carried out to simulate a more complex experimental situation and evaluated their proposed method. Second, the physical cylinder phantom experiments further showed similar results in their prototype XLCT system. With the discussion of the above experiments, it was shown that the proposed method is feasible to the general case and actual experiments. Conclusions: Utilizing numerical simulation and physical experiments, the authors demonstrated the validity of the new cone beam XLCT method. Furthermore, compared with the previous narrow beam XLCT, the cone beam XLCT could more fully utilize the x-ray dose and the scanning time would be shortened greatly. The study of both simulation experiments and physical phantom experiments indicated that the proposed method was feasible to the general case and actual experiments.

  13. Optical, UV, and X-ray Clues to the Nature of Narrow Line AGNs

    E-Print Network [OSTI]

    Ari Laor

    2000-05-08T23:59:59.000Z

    AGNs with narrow Balmer lines show various extreme properties. In particular, rapid X-ray variability, steep X-ray spectra, peculiar optical and UV line ratios, and possibly peculiar line profiles. Since all these phenomena occur together they are likely to be related to one specific underlying physical parameter. I review recent evidence, based on HST imaging of low z quasars, which suggests that the H-beta line width and continuum luminosity of quasars provide a reasonably accurate estimate of the black hole mass. This implies that narrow-line AGN have relatively low black hole masses, and thus high L/L_Edd, as independently suggested based on their steep X-ray spectra. I present additional evidence suggesting that the X-ray variability and the radio loudness are primarily driven by the black hole mass. The high mass inflow rate into the core of narrow-line AGNs may produce a denser and more enriched BLR, a high column radiation pressure driven outflow, and a smaller illumination angle for the NLR, as suggested by the observed emission line properties. Narrow-line AGNs may thus provide important clues for understanding the rich overall phenomenology of AGNs.

  14. Ultra-short wavelength x-ray system

    DOE Patents [OSTI]

    Umstadter, Donald (Ann Arbor, MI); He, Fei (Ann Arbor, MI); Lau, Yue-Ying (Potomac, MD)

    2008-01-22T23:59:59.000Z

    A method and apparatus to generate a beam of coherent light including x-rays or XUV by colliding a high-intensity laser pulse with an electron beam that is accelerated by a synchronized laser pulse. Applications include x-ray and EUV lithography, protein structural analysis, plasma diagnostics, x-ray diffraction, crack analysis, non-destructive testing, surface science and ultrafast science.

  15. Legacy of the X-Ray Laser Program

    SciTech Connect (OSTI)

    Nilsen, J.

    1993-08-06T23:59:59.000Z

    The X-Ray Laser Program has evolved from a design effort focusing on developing a Strategic Defense Initiative weapon that protects against Soviet ICBMs to a scientific project that is producing new technologies for industrial and medical research. While the great technical successes and failures of the X-ray laser itself cannot be discussed, this article presents the many significant achievements made as part of the X-ray laser effort that are now being used for other applications at LLNL.

  16. Sum rules for polarization-dependent x-ray absorption

    SciTech Connect (OSTI)

    Ankudinov, A.; Rehr, J.J. (Department of Physics, FM-15, University of Washington, Seattle, Washington 98195 (United States))

    1995-01-01T23:59:59.000Z

    A complete set of sum rules is obtained for polarization-dependent x-ray-absorption fine structure and x-ray circular magnetic dichroism (CMD), analogous to those for CMD derived by Thole [ital et] [ital al]. These sum rules relate x-ray-absorption coefficients to the ground-state expectation values of various operators. Problems with applying these sum rules are discussed.

  17. Relationship between dislocations and residual stresses in cold-drawn pearlitic steel analyzed by energy-dispersive X-ray diffraction

    SciTech Connect (OSTI)

    Sato, Shigeo, E-mail: s.sato@imr.tohoku.ac.jp [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Wagatsuma, Kazuaki [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Suzuki, Shigeru [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577 (Japan); Kumagai, Masayoshi; Imafuku, Muneyuki [Faculty of Engineering, Tokyo City University, Tokyo 158-8557 (Japan); Tashiro, Hitoshi [Gyoda 361-0011 (Japan); Kajiwara, Kentaro [Japan Synchrotron Radiation Research Institute, Sayo 679-5198 (Japan); Shobu, Takahiasa [Japan Atomic Energy Agency, Sayo 679-5184 (Japan)

    2013-09-15T23:59:59.000Z

    We analyzed the dislocation distribution of cold-drawn pearlitic-steel wire by using the line-profile analysis based on the energy dispersive X-ray diffraction (EDXD). Although this line-profile analysis requires a high resolution in reciprocal space, the resolution for EDXD is generally poor due to the energy resolution of the detector. Our analysis demonstrated that the resolution in the reciprocal space can be maximized at small scattering angles. Using the line-profile analysis based on the EDXD, the microstructural parameters such as the crystallite size and the dislocation density of the ferrite phase in the pearlitic steel were successfully analyzed. In addition, the distribution of the residual stress of the ferrite phase of a pearlitic steel wire was also analyzed using the EDXD measurement. - Highlights: • Energy dispersive X-ray diffraction is applied to the line-profile analysis. • Distribution of dislocations in ferrite in the pearlitic steel wire is analyzed. • Relationship between dislocations and residual stress is discussed.

  18. Part I: Instrumentation The Chandra X-ray Observatory and

    E-Print Network [OSTI]

    -ray Observatory showing the HRMA, four sci- entific instruments (two types of gratings, HRC, and ACIS) and major://asc.harvard.edu. 2.2 Scientific Instruments 2.2.1 HRMA At energies above 10 eV, photons scatter at incident angles and (usually) prohibitively expensive endeavor. The High Resolution Mirror Assembly (HRMA) gives Chandra

  19. X-RAY ECLIPSE DIAGNOSIS OF THE EVOLVING MASS LOSS IN THE RECURRENT NOVA U SCORPII 2010

    SciTech Connect (OSTI)

    Takei, D.; Drake, J. J. [Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 (United States); Tsujimoto, M. [Japan Aerospace Exploration Agency, Institute of Space and Astronautical Science, 3-1-1 Yoshino-dai, Chuo-ku, Sagamihara, Kanagawa 252-5210 (Japan); Ness, J.-U. [European Space Agency, XMM-Newton Observatory SOC, SRE-OAX, Apartado 78, E-28691 Villanueva de la Canada, Madrid (Spain); Osborne, J. P. [Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH (United Kingdom); Starrfield, S. [School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287-1404 (United States); Kitamoto, S., E-mail: dtakei@head.cfa.harvard.edu [Department of Physics, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima, Tokyo 171-8501 (Japan)

    2013-05-20T23:59:59.000Z

    We report the Suzaku detection of the earliest X-ray eclipse seen in the recurrent nova U Scorpii 2010. A target-of-opportunity observation 15 days after the outburst found a 27% {+-} 5% dimming in the 0.2-1.0 keV energy band at the predicted center of an eclipse. In comparison with the X-ray eclipse depths seen at two later epochs by XMM-Newton, the source region shrank by about 10%-20% between days 15 and 35 after the outburst. The X-ray eclipses appear to be deeper than or similar to contemporaneous optical eclipses, suggesting the X-ray and optical source region extents are comparable on day 15. We raise the possibility of the energy dependency in the photon escape regions, and that this would be a result of the supersoft X-ray opacity being higher than the Thomson scattering opacity at the photosphere due to bound-free transitions in abundant metals that are not fully ionized. Assuming a spherically symmetric model, we constrain the mass-loss rate as a function of time. For a ratio of actual to Thomson opacity of 10-100 in supersoft X-rays, we find an ejecta mass of about 10{sup -7}-10{sup -6} M{sub Sun }.

  20. A laser triggered vacuum spark x-ray lithography source

    E-Print Network [OSTI]

    Keating, Richard Allen

    1987-01-01T23:59:59.000Z

    ionized state or the physical processes occurring 15 in a high temperature plasma. There are many advantages to the use of the vacuum spark as an x-ray source; the simplicity of the machine is one. The x-ray output is within the range usable for x-ray... spark apparatus ha- been studied here to determine its applicability to x-ray lithography. A capacitor which stored approximately 3 KJ supplied most of the energy for the plasma. A Nd-YAG laser was used to supply electrons and metallic atoms...