Sample records for interface x-ray method

  1. 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

  2. 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

  3. X-ray laser system, x-ray laser and method

    DOE Patents [OSTI]

    London, Richard A. (Oakland, CA); Rosen, Mordecai D. (Berkeley, CA); Strauss, Moshe (Omer, IL)

    1992-01-01T23:59:59.000Z

    Disclosed is an x-ray laser system comprising a laser containing generating means for emitting short wave length radiation, and means external to said laser for energizing said generating means, wherein when the laser is in an operative mode emitting radiation, the radiation has a transverse coherence length to width ratio of from about 0.05 to 1. Also disclosed is a method of adjusting the parameters of the laser to achieve the desired coherence length to laser width ratio.

  4. Systems and methods for detecting x-rays

    DOE Patents [OSTI]

    Bross, Alan D.; Mellott, Kerry L.; Pla-Dalmau, Anna

    2006-05-02T23:59:59.000Z

    Systems and methods for detecting x-rays are disclosed herein. One or more x-ray-sensitive scintillators can be configured from a plurality of heavy element nano-sized particles and a plastic material, such as polystyrene. As will be explained in greater detail herein, the heavy element nano-sized particles (e.g., PbWO4) can be compounded into the plastic material with at least one dopant that permits the plastic material to scintillate. X-rays interact with the heavy element nano-sized particles to produce electrons that can deposit energy in the x-ray sensitive scintillator, which in turn can produce light.

  5. X-ray mask and method for making

    DOE Patents [OSTI]

    Morales, Alfredo M.

    2004-10-26T23:59:59.000Z

    The present invention describes a method for fabricating an x-ray mask tool which is a contact lithographic mask which can provide an x-ray exposure dose which is adjustable from point-to-point. The tool is useful in the preparation of LIGA plating molds made from PMMA, or similar materials. In particular the tool is useful for providing an ability to apply a graded, or "stepped" x-ray exposure dose across a photosensitive substrate. By controlling the x-ray radiation dose from point-to-point, it is possible to control the development process for removing exposed portions of the substrate; adjusting it such that each of these portions develops at a more or less uniformly rate regardless of feature size or feature density distribution.

  6. Archaeometrical studies using X-ray fluorescence methods

    SciTech Connect (OSTI)

    Pauna, Catalina; Constantinescu, B.; Constantin, F.; Bugoi, R.; Stan, D.; Vasilescu, A. [National Institute of Nuclear Physics and Engineering, POB MG-6, 077125, Bucharest (Romania)

    2010-04-26T23:59:59.000Z

    Elemental analysis contributes to authentication (knowing the elemental composition and considering the information about the usual composition of the objects in different historical periods it can be established if the item is original or fake), provenance studies (minor and trace elements indicates ores origin and 'consequently' mines location), (relative) dating of archaeological objects (e.g. for painted items--the chemical recipes for pigments can offer information about the age of objects). The paper gives a general layout for the NIPNE Archaeometry Laboratory's applications using X-Ray Fluorescence (XRF), micro--Proton Induced X-Ray Emission (micro-PIXE), micro-Synchrotron Radiation Induced X-Ray Fluorescence (micro--SR-XRF) methods.

  7. X-ray standing waves and surface EXAFS studies of electrochemical interfaces

    SciTech Connect (OSTI)

    Abruna, H.D.; Bommarito, G.M.; Yee, H.S. [Cornell Univ., Ithaca, NY (United States)

    1995-06-01T23:59:59.000Z

    Because of their penetrative power, X-rays are ideally suited for in-situ studies of interfaces in general and solid/liquid interfaces in particular. The recent advent of powerful X-ray synchrotron sources has made experiments of this type feasible. Synchrotron sources offer a broad spectral range of polarized, highly collimated X-rays with intensities that are 10{sup 3}-10{sup 6} higher than those of conventional sources. Moreover, third-generation synchrotron sources, with their projected increase in brightness on the order of 10{sup 4}, will allow for new types of experiments, including the study of dynamic processes in real time. There are a number of X-ray-based surface-sensitive techniques that can be employed in the study of solid/liquid interfaces, including surface EXAFS, X-ray standing waves (XSW), grazing incidence X-ray diffraction (GIXD), and others. In this Account the authors focus on the use of XSW and surface EXAFS. The authors begin with a brief theoretical description followed by experimental aspects of these techniques. The authors then discuss specific examples with emphasis on the underpotential deposition of copper on platinum in the presence and absence of coadsorbates, the potential dependent distribution of interfacial species, and potential dependent structural changes of a redox-active self-assembling monolayer. 33 refs., 7 figs.

  8. 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.

  9. Simple Method for Estimating and Comparing of X-Ray Damage Rates...

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

    Method for Estimating and Comparing of X-Ray Damage Rates. Simple Method for Estimating and Comparing of X-Ray Damage Rates. Abstract: This note describes an approach for...

  10. Using “Tender” x-ray ambient pressure x-Ray photoelectron spectroscopy as a direct probe of solid-liquid interface

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

    Axnanda, Stephanus [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Crumlin, Ethan J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mao, Baohua [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Chinese Academy of Sciences, Shanghai (Republic of China); Rani, Sana [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Chang, Rui [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Chinese Academy of Sciences, Shanghai (Republic of China); Karlsson, Patrik G. [VG Scienta,Uppsala (Sweden); Edwards, Mårten O. M. [VG Scienta,Uppsala (Sweden); Lundqvist, Måns [VG Scienta,Uppsala (Sweden); Moberg, Robert [VG Scienta,Uppsala (Sweden); Ross, Phil [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hussain, Zahid [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Liu, Zhi [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Chinese Academy of Sciences, Shanghai (Republic of China); Shanghai Tech Univ., Shanghai (China)

    2015-05-07T23:59:59.000Z

    We report a new method to probe the solid-liquid interface through the use of a thin liquid layer on a solid surface. An ambient pressure XPS (AP-XPS) endstation that is capable of detecting high kinetic energy photoelectrons (7 keV) at a pressure up to 110 Torr has been constructed and commissioned. Additionally, we have deployed a “dip & pull” method to create a stable nanometers-thick aqueous electrolyte on platinum working electrode surface. Combining the newly constructed AP-XPS system, “dip & pull” approach, with a “tender” X-ray synchrotron source (2 keV–7 keV), we are able to access the interface between liquid and solid dense phases with photoelectrons and directly probe important phenomena occurring at the narrow solid-liquid interface region in an electrochemical system. Using this approach, we have performed electrochemical oxidation of the Pt electrode at an oxygen evolution reaction (OER) potential. Under this potential, we observe the formation of both Pt²? and Pt?? interfacial species on the Pt working electrode in situ. We believe this thin-film approach and the use of “tender” AP-XPS highlighted in this study is an innovative new approach to probe this key solid-liquid interface region of electrochemistry.

  11. Using “Tender” x-ray ambient pressure x-Ray photoelectron spectroscopy as a direct probe of solid-liquid interface

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

    Axnanda, Stephanus; Crumlin, Ethan J.; Mao, Baohua; Rani, Sana; Chang, Rui; Karlsson, Patrik G.; Edwards, Mårten O. M.; Lundqvist, Måns; Moberg, Robert; Ross, Phil; et al

    2015-05-07T23:59:59.000Z

    We report a new method to probe the solid-liquid interface through the use of a thin liquid layer on a solid surface. An ambient pressure XPS (AP-XPS) endstation that is capable of detecting high kinetic energy photoelectrons (7 keV) at a pressure up to 110 Torr has been constructed and commissioned. Additionally, we have deployed a “dip & pull” method to create a stable nanometers-thick aqueous electrolyte on platinum working electrode surface. Combining the newly constructed AP-XPS system, “dip & pull” approach, with a “tender” X-ray synchrotron source (2 keV–7 keV), we are able to access the interface between liquidmore »and solid dense phases with photoelectrons and directly probe important phenomena occurring at the narrow solid-liquid interface region in an electrochemical system. Using this approach, we have performed electrochemical oxidation of the Pt electrode at an oxygen evolution reaction (OER) potential. Under this potential, we observe the formation of both Pt²? and Pt?? interfacial species on the Pt working electrode in situ. We believe this thin-film approach and the use of “tender” AP-XPS highlighted in this study is an innovative new approach to probe this key solid-liquid interface region of electrochemistry.« less

  12. Apparatus and method to enhance X-ray production in laser produced plasmas

    DOE Patents [OSTI]

    Augustoni, Arnold L. (Albuquerque, NM); Gerardo, James B. (Albuquerque, NM); Raymond, Thomas D. (Albuquerque, NM)

    1992-01-01T23:59:59.000Z

    Method and apparatus for generating x-rays for use in, for instance, x-ray photolithography. The method of generating x-rays includes the steps of providing a target and irradiating the target with a laser system which produces a train of sub-pulses to generate an x-ray producing plasma. The sub-pulses are of both high intensity and short duration. The apparatus for generating x-rays from a plasma includes a vacuum chamber, a target supported within the chamber and a laser system, including a short storage time laser.

  13. Apparatus and method to enhance X-ray production in laser produced plasmas

    DOE Patents [OSTI]

    Augustoni, A.L.; Gerardo, J.B.; Raymond, T.D.

    1992-12-29T23:59:59.000Z

    Method and apparatus for generating x-rays for use in, for instance, x-ray photolithography is disclosed. The method of generating x-rays includes the steps of providing a target and irradiating the target with a laser system which produces a train of sub-pulses to generate an x-ray producing plasma. The sub-pulses are of both high intensity and short duration. The apparatus for generating x-rays from a plasma includes a vacuum chamber, a target supported within the chamber and a laser system, including a short storage time laser. 8 figs.

  14. Dual x-ray fluorescence spectrometer and method for fluid analysis

    DOE Patents [OSTI]

    Wilson, Bary W.; Shepard, Chester L.

    2005-02-22T23:59:59.000Z

    Disclosed are an X-ray fluorescence (SRF) spectrometer and method for on-site and in-line determination of contaminant elements in lubricating oils and in fuel oils on board a marine vessel. An XRF source block 13 contains two radionuclide sources 16, 17 (e.g. Cd 109 and Fe 55), each oriented 180 degrees from the other to excite separate targets. The Cd 109 source 16 excites sample lube oil flowing through a low molecular weight sample line 18. The Fe 55 source 17 excites fuel oil manually presented to the source beam inside a low molecular weight vial 26 or other container. Two separate detectors A and B are arranged to detect the fluorescent x-rays from the targets, photons from the analyte atoms in the lube oil for example, and sulfur identifying x-rays from bunker fuel oil for example. The system allows both automated in-line and manual on-site analysis using one set of signal processing and multi-channel analyzer electronics 34, 37 as well as one computer 39 and user interface 43.

  15. Method and apparatus for micromachining using hard X-rays

    DOE Patents [OSTI]

    Siddons, David Peter (Shoreham, NY); Johnson, Erik D. (Ridge, NY); Guckel, Henry (Madison, WI); Klein, Jonathan L. (Madison, WI)

    1997-10-21T23:59:59.000Z

    An X-ray source such as a synchrotron which provides a significant spectral content of hard X-rays is used to expose relatively thick photoresist such that the portions of the photoresist at an exit surface receive at least a threshold dose sufficient to render the photoresist susceptible to a developer, while the entrance surface of the photoresist receives an exposure which does not exceed a power limit at which destructive disruption of the photoresist would occur. The X-ray beam is spectrally shaped to substantially eliminate lower energy photons while allowing a substantial flux of higher energy photons to pass through to the photoresist target. Filters and the substrate of the X-ray mask may be used to spectrally shape the X-ray beam. Machining of photoresists such as polymethylmethacrylate to micron tolerances may be obtained to depths of several centimeters, and multiple targets may be exposed simultaneously. The photoresist target may be rotated and/or translated in the beam to form solids of rotation and other complex three-dimensional structures.

  16. Method and apparatus for micromachining using hard X-rays

    DOE Patents [OSTI]

    Siddons, D.P.; Johnson, E.D.; Guckel, H.; Klein, J.L.

    1997-10-21T23:59:59.000Z

    An X-ray source such as a synchrotron which provides a significant spectral content of hard X-rays is used to expose relatively thick photoresist such that the portions of the photoresist at an exit surface receive at least a threshold dose sufficient to render the photoresist susceptible to a developer, while the entrance surface of the photoresist receives an exposure which does not exceed a power limit at which destructive disruption of the photoresist would occur. The X-ray beam is spectrally shaped to substantially eliminate lower energy photons while allowing a substantial flux of higher energy photons to pass through to the photoresist target. Filters and the substrate of the X-ray mask may be used to spectrally shape the X-ray beam. Machining of photoresists such as polymethylmethacrylate to micron tolerances may be obtained to depths of several centimeters, and multiple targets may be exposed simultaneously. The photoresist target may be rotated and/or translated in the beam to form solids of rotation and other complex three-dimensional structures. 21 figs.

  17. Postmortem analysis of sand grain crushing from pile interface using X-ray tomography

    SciTech Connect (OSTI)

    Silva, I. Matias; Combe, Gaeel; Foray, Pierre; Flin, Frederic; Lesaffre, Bernard [Universite de Grenoble, 3SR Lab, UMR 5521 Grenoble-INP, UJF-Grenoble 1, CNRS, Grenoble, France CEN, CNRM-GAME UMR 3589, Meteo France - CNRS, Grenoble (France)

    2013-06-18T23:59:59.000Z

    Pile foundations of offshore platforms, wind and water turbines are typically subjected to a variety of cyclic loading paths due to their complex environment. While many studies focus on global pile behaviour, the soil-pile interface is explored here by a micromechanical study of the soil layer in contact with the pile surface. This work is devoted to the analysis of frozen post-mortem silica sand samples recovered at the pile interface following installation and cyclic loading tests in a calibration chamber using x-ray tomography. An experimental procedure developed for three dimensional (3D) snow imaging was adapted for the recovery of the in-situ sand samples to preserve their structure during tomography scans. 3D images at a pixel size of 7 {mu}m were then obtained using a cryogenic cell. Results confirm the presence of a shear band at the pile surface as well as void ratios changes in the direction of the pile's radius.

  18. Reactive ZnO/Ti/ZnO interfaces studied by hard x-ray photoelectron spectroscopy

    SciTech Connect (OSTI)

    Knut, Ronny, E-mail: Ronny.Knut@physics.gu.se; Lindblad, Rebecka; Rensmo, Håkan; Karis, Olof [Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala (Sweden); Grachev, Sergey; Faou, Jean-Yvon; Søndergård, Elin [Unité Mixte CNRS/Sain-Gobain Recherche, 39 Quai Lucien Lefranc, 93303 Aubervilliers (France); Gorgoi, Mihaela [Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Str. 15, D-12489 Berlin (Germany)

    2014-01-28T23:59:59.000Z

    The chemistry and intermixing at buried interfaces in sputter deposited ZnO/Ti/ZnO thin layers were studied by hard x-ray photoelectron spectroscopy. The long mean free path of the photoelectrons allowed for detailed studies of the oxidation state, band bending effects, and intrinsic doping of the buried interfaces. Oxidation of the Ti layer was observed when ZnO was deposited on top. When Ti is deposited onto ZnO, Zn Auger peaks acquire a metallic character indicating a strong reduction of ZnO at the interface. Annealing of the stack at 200?°C results in further reduction of ZnO and oxidation of Ti. Above 300?°C, oxygen transport from the bulk of the ZnO layer takes place, leading to re-oxidation of ZnO at the interface and further oxidation of Ti layer. Heating above 500?°C leads to an intermixing of the layers and the formation of a Zn{sub x}TiO{sub y} compound.

  19. Method and apparatus for producing durationally short ultraviolet or X-ray laser pulses

    DOE Patents [OSTI]

    MacGowan, Brian J. (Livermore, CA); Matthews, Dennis L. (El Granada, CA); Trebes, James E. (Livermore, CA)

    1988-01-01T23:59:59.000Z

    A method and apparatus is disclosed for producing ultraviolet or X-ray laser pulses of short duration (32). An ultraviolet or X-ray laser pulse of long duration (12) is progressively refracted, across the surface of an opaque barrier (28), by a streaming plasma (22) that is produced by illuminating a solid target (16, 18) with a pulse of conventional line focused high power laser radiation (20). The short pulse of ultraviolet or X-ray laser radiation (32), which may be amplified to high power (40, 42), is separated out by passage through a slit aperture (30) in the opaque barrier (28).

  20. Method for detecting binding events using micro-X-ray fluorescence spectrometry

    DOE Patents [OSTI]

    Warner, Benjamin P. (Los Alamos, NM); Havrilla, George J. (Los Alamos, NM); Mann, Grace (Hong Kong, HK)

    2010-12-28T23:59:59.000Z

    Method for detecting binding events using micro-X-ray fluorescence spectrometry. Receptors are exposed to at least one potential binder and arrayed on a substrate support. Each member of the array is exposed to X-ray radiation. The magnitude of a detectable X-ray fluorescence signal for at least one element can be used to determine whether a binding event between a binder and a receptor has occurred, and can provide information related to the extent of binding between the binder and receptor.

  1. Method and apparatus for producing durationally short ultraviolet or x-ray laser pulses

    DOE Patents [OSTI]

    MacGowan, B.J.; Matthews, D.L.; Trebes, J.E.

    1987-05-05T23:59:59.000Z

    A method and apparatus is disclosed for producing ultraviolet or x- ray laser pulses of short duration. An ultraviolet or x-ray laser pulse of long duration is progressively refracted, across the surface of an opaque barrier, by a streaming plasma that is produced by illuminating a solid target with a pulse of conventional line focused high power laser radiation. The short pulse of ultraviolet or x-ray laser radiation, which may be amplified to high power, is separated out by passage through a slit aperture in the opaque barrier.

  2. High efficiency replicated x-ray optics and fabrication method

    DOE Patents [OSTI]

    Barbee, Jr., Troy W. (Palo Alto, CA); Lane, Stephen M. (Oakland, CA); Hoffman, Donald E. (Fremont, CA)

    2001-01-01T23:59:59.000Z

    Replicated x-ray optics are fabricated by sputter deposition of reflecting layers on a super-polished reusable mandrel. The reflecting layers are strengthened by a supporting multilayer that results in stronger stress-relieved reflecting surfaces that do not deform during separation from the mandrel. The supporting multilayer enhances the ability to part the replica from the mandrel without degradation in surface roughness. The reflecting surfaces are comparable in smoothness to the mandrel surface. An outer layer is electrodeposited on the supporting multilayer. A parting layer may be deposited directly on the mandrel before the reflecting surface to facilitate removal of the layered, tubular optic device from the mandrel without deformation. The inner reflecting surface of the shell can be a single layer grazing reflection mirror or a resonant multilayer mirror. The resulting optics can be used in a wide variety of applications, including lithography, microscopy, radiography, tomography, and crystallography.

  3. Postmortem analysis of sand grain crushing from pile interface using X-ray I. Matas Silva, Gal Combe, Pierre Foray, Frdric Flin, and Bernard Lesaffre

    E-Print Network [OSTI]

    Ribes, Aurélien

    Postmortem analysis of sand grain crushing from pile interface using X-ray tomography I. Matías of Sand Grain Crushing From Pile Interface Using X-ray Tomography Matías Silva I., Gaël Combe, Pierre. Pile foundations of offshore platforms, wind and water turbines are typically subjected to a variety

  4. Smoothed Particle Inference: A Kilo-Parametric Method for X-ray Galaxy Cluster Modeling

    SciTech Connect (OSTI)

    Peterson, John R.; Marshall, P.J.; /KIPAC, Menlo Park; Andersson, K.; /Stockholm U. /SLAC

    2005-08-05T23:59:59.000Z

    We propose an ambitious new method that models the intracluster medium in clusters of galaxies as a set of X-ray emitting smoothed particles of plasma. Each smoothed particle is described by a handful of parameters including temperature, location, size, and elemental abundances. Hundreds to thousands of these particles are used to construct a model cluster of galaxies, with the appropriate complexity estimated from the data quality. This model is then compared iteratively with X-ray data in the form of adaptively binned photon lists via a two-sample likelihood statistic and iterated via Markov Chain Monte Carlo. The complex cluster model is propagated through the X-ray instrument response using direct sampling Monte Carlo methods. Using this approach the method can reproduce many of the features observed in the X-ray emission in a less assumption-dependent way that traditional analyses, and it allows for a more detailed characterization of the density, temperature, and metal abundance structure of clusters. Multi-instrument X-ray analyses and simultaneous X-ray, Sunyaev-Zeldovich (SZ), and lensing analyses are a straight-forward extension of this methodology. Significant challenges still exist in understanding the degeneracy in these models and the statistical noise induced by the complexity of the models.

  5. Effects of Fresnel fringes on TEM images of interfaces in X-ray multil ayers

    E-Print Network [OSTI]

    Nguyen, Tai D.; O'Keefe, Michael A.; Kilaas, Roar; Gronsky, Ronald; Kortright, Jeffrey B.

    1992-01-01T23:59:59.000Z

    and J.B. Kortright, Fresnel Fringe Effects at Interfaces ofand T.F. Page, A TEM Fresnel Diffraction-Based Method forW/Si Multilayers Using The Fresnel Method, Ultramicroscopy

  6. Iron near absorption edge X-ray spectroscopy at aqueous-membrane interfaces

    SciTech Connect (OSTI)

    Wang, Wenjie; Kuzmenko, Ivan; Vaknin, David

    2014-01-01T23:59:59.000Z

    Employing synchrotron X-ray scattering, we systematically determine the absorption near-edge spectra (XANES) of iron in its ferrous (Fe2+) and ferric (Fe3+) states both as ions in aqueous solutions and as they bind to form a single layer to anionic templates that consist of carboxyl or phosphate groups at aqueous/vapor interfaces. While the XANES of bulk iron ions show that the electronic state and coordination of iron complexes in the bulk are isotropic, the interfacial bound ions show a signature of a broken inversion-symmetry environment. The XANES of Fe2+ and Fe3+ in the bulk possess distinct profiles however, upon binding they practically exhibit similar patterns. This indicates that both bound ions settle into a stable electronic and coordination configuration with an effective fractional valence (for example, Fe[2+nu]+, 0 < nu < 1) at charged organic templates. Such two dimensional properties may render interfacial iron, abundant in living organisms, a more efficient and versatile catalytic behavior.

  7. X-RAY FLUORESCENCE ANALYSIS OF HANFORD LOW ACTIVITY WASTE SIMULANTS METHOD DEVELOPMENT

    SciTech Connect (OSTI)

    Jurgensen, A; David Missimer, D; Ronny Rutherford, R

    2007-08-08T23:59:59.000Z

    The x-ray fluorescence laboratory (XRF) in the Analytical Development Directorate (ADD) of the Savannah River National Laboratory (SRNL) was requested to develop an x-ray fluorescence spectrometry method for elemental characterization of the Hanford Tank Waste Treatment and Immobilization Plant (WTP) pretreated low activity waste (LAW) stream to the LAW Vitrification Plant. The WTP is evaluating the potential for using XRF as a rapid turnaround technique to support LAW product compliance and glass former batching. The overall objective of this task was to develop an XRF analytical method that provides rapid turnaround time (<8 hours), while providing sufficient accuracy and precision to determine variations in waste.

  8. Synchrotron X-ray Studies of Super-critical Carbon Dioxide / Reservoir Rock Interfaces

    Broader source: Energy.gov [DOE]

    Project obectives: Utilize synchrotron X-ray measurements, to monitor all aspects of atomic to nanoscale structural changes resulting from chemical interactions of scCO2-H2O binary fluids with rocks under environments directly relevant to EGS.

  9. X-ray photon-in/photon-out methods for chemical imaging

    SciTech Connect (OSTI)

    Marcus, Matthew A.

    2010-03-24T23:59:59.000Z

    Most interesting materials in nature are heterogeneous, so it is useful to have analytical techniques with spatial resolution sufficient to resolve these heterogeneities.This article presents the basics of X-ray photon-in/photon-out chemical imaging. This family of methods allows one to derive images reflectingthe chemical state of a given element in a complex sample, at micron or deep sub-micron scale. X-ray chemical imaging is relatively non-destructiveand element-selective, and requires minimal sample preparation. The article presents the basic concepts and some considerations of data takingand data analysis, along with some examples.

  10. Method and apparatus for digitally based high speed x-ray spectrometer

    DOE Patents [OSTI]

    Warburton, William K. (1300 Mills St., Menlo Park, CA 94025); Hubbard, Bradley (Santa Cruz, CA)

    1997-01-01T23:59:59.000Z

    A high speed, digitally based, signal processing system which accepts input data from a detector-preamplifier and produces a spectral analysis of the x-rays illuminating the detector. The system achieves high throughputs at low cost by dividing the required digital processing steps between a "hardwired" processor implemented in combinatorial digital logic, which detects the presence of the x-ray signals in the digitized data stream and extracts filtered estimates of their amplitudes, and a programmable digital signal processing computer, which refines the filtered amplitude estimates and bins them to produce the desired spectral analysis. One set of algorithms allow this hybrid system to match the resolution of analog systems while operating at much higher data rates. A second set of algorithms implemented in the processor allow the system to be self calibrating as well. The same processor also handles the interface to an external control computer.

  11. Method and apparatus for digitally based high speed x-ray spectrometer

    DOE Patents [OSTI]

    Warburton, W.K.; Hubbard, B.

    1997-11-04T23:59:59.000Z

    A high speed, digitally based, signal processing system which accepts input data from a detector-preamplifier and produces a spectral analysis of the x-rays illuminating the detector. The system achieves high throughputs at low cost by dividing the required digital processing steps between a ``hardwired`` processor implemented in combinatorial digital logic, which detects the presence of the x-ray signals in the digitized data stream and extracts filtered estimates of their amplitudes, and a programmable digital signal processing computer, which refines the filtered amplitude estimates and bins them to produce the desired spectral analysis. One set of algorithms allow this hybrid system to match the resolution of analog systems while operating at much higher data rates. A second set of algorithms implemented in the processor allow the system to be self calibrating as well. The same processor also handles the interface to an external control computer. 19 figs.

  12. Multilayer films with sharp, stable interfaces for use in EUV and soft X-ray application

    DOE Patents [OSTI]

    Barbee, Jr., Troy W. (Palo Alto, CA); Bajt, Sasa (Livermore, CA)

    2002-01-01T23:59:59.000Z

    The reflectivity and thermal stability of Mo/Si (molybdenum/silicon) multilayer films, used in soft x-ray and extreme ultraviolet region, is enhanced by deposition of a thin layer of boron carbide (e.g., B.sub.4 C) between alternating layers of Mo and Si. The invention is useful for reflective coatings for soft X-ray and extreme ultraviolet optics, multilayer for masks, coatings for other wavelengths and multilayers for masks that are more thermally stable than pure Mo/Si multilayers

  13. 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.

  14. A method of measuring gold nanoparticle concentrations by x-ray fluorescence for biomedical applications

    SciTech Connect (OSTI)

    Wu Di; Li Yuhua; Wong, Molly D.; Liu Hong [Center for Bioengineering and School of Electrical and Computer Engineering, University of Oklahoma, Norman, Oklahoma 73019 (United States)

    2013-05-15T23:59:59.000Z

    Purpose: This paper reports a technique that enables the quantitative determination of the concentration of gold nanoparticles (GNPs) through the accurate detection of their fluorescence radiation in the diagnostic x-ray spectrum. Methods: Experimentally, x-ray fluorescence spectra of 1.9 and 15 nm GNP solutions are measured using an x-ray spectrometer, individually and within chicken breast tissue samples. An optimal combination of excitation and emission filters is determined to segregate the fluorescence spectra at 66.99 and 68.80 keV from the background scattering. A roadmap method is developed that subtracts the scattered radiation (acquired before the insertion of GNP solutions) from the signal radiation acquired after the GNP solutions are inserted. Results: The methods effectively minimize the background scattering in the spectrum measurements, showing linear relationships between GNP solutions from 0.1% to 10% weight concentration and from 0.1% to 1.0% weight concentration inside a chicken breast tissue sample. Conclusions: The investigation demonstrated the potential of imaging gold nanoparticles quantitatively in vivo for in-tissue studies, but future studies will be needed to investigate the ability to apply this method to clinical applications.

  15. Magnetism at spinel thin film interfaces probed through soft x-ray spectroscopy techniques

    E-Print Network [OSTI]

    Chopdekar, R.V.

    2010-01-01T23:59:59.000Z

    Magnetism at spinel thin ?lm interfaces probed through softachievable in bulk form. Magnetism at the interface regionand the origin of the magnetism from multiple magnetic

  16. X-ray pulse preserving single-shot optical cross-correlation method for improved experimental temporal resolution

    SciTech Connect (OSTI)

    Beye, M. [SIMES, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, 12489 Berlin (Germany); Krupin, O. [LCLS, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); European XFEL GmbH, 22607 Hamburg (Germany); Hays, G.; Jong, S. de; Lee, S.; Coffee, R.; Holmes, M. R.; Fry, A. R.; White, W. E.; Bostedt, C.; Schlotter, W. F. [LCLS, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Reid, A. H. [SIMES, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Radboud University Nijmegen, Institute for Molecules and Materials, 6525 AJ Nijmegen (Netherlands); Rupp, D. [Technische Universitaet Berlin, 10623 Berlin (Germany); LCLS, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Lee, W.-S.; Scherz, A. O. [SIMES, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Chuang, Y.-D. [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Cryan, J. P.; Glownia, J. M. [PULSE, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); LCLS, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Foehlisch, A. [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, 12489 Berlin (Germany); Durr, H. A. [SIMES, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); PULSE, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States)

    2012-03-19T23:59:59.000Z

    We measured the relative arrival time between an optical pulse and a soft x-ray pulse from a free-electron laser. This femtosecond cross-correlation measurement was achieved by observing the change in optical reflectivity induced through the absorption of a fraction of the x-ray pulse. The main x-ray pulse energy remained available for an independent pump-probe experiment where the sample may be opaque to soft x-rays. The method was employed to correct the two-pulse delay data from a canonical pump-probe experiment and demonstrate 130 {+-} 20 fs (FWHM) temporal resolution. We further analyze possible timing jitter sources and point to future improvements.

  17. 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

  18. Bone Implant Interface Investigation by Synchrotron Radiation X-Ray Microfluorescence

    SciTech Connect (OSTI)

    Calasans-Maia, M. [Odondology Department, Fluminense Federal Univeristy, Niteroi 24030-900, RJ (Brazil); Sales, E.; Lopes, R. T. [Nuclear Instrumentation Laboratory-PEN/COPPE, Federal Univeristy of Rio de Janeiro, Rio de Janeiro 21941-914, RJ (Brazil); Granjeiro, J. M. [Department of Cell and Molecular Biology, Fluminense Federal University, Niteroi 24030-900, RJ (Brazil); Lima, I. [Odondology Department, Fluminense Federal Univeristy, Niteroi 24030-900, RJ (Brazil); Department of Mechanical Engineering and Energy, Rio de Janeiro State University, Regional Campus-Polytechnic Institute-Alberto Rangel, s/n, Vila Nova, room 308, 28630-050, Nova Friburgo, RJ (Brazil)

    2010-04-06T23:59:59.000Z

    Zinc is known to play a relevant role in growth and development; it has stimulatory effects on in vitro and in vivo bone formation and an inhibitory effect on in vitro osteoclastic bone resorption. The inorganic component of the bone tissue is nonstoichiometric apatite; changes in the composition of hidroxyapatite are subject of studies in order to improve the tissue response after implantation. The objective of this study was to investigate the effect of 0.5% zinc-containing hydroxyapatite in comparison to hydroxyapatite on osseous repair of rabbit's tibia. Cylinders (2x6 mm) of both materials were produced according to the specification of the International Organization for Standardization. Ethics Commission on Teaching and Research in Animals approved this project (HUAP-195/06). Fifteen White New Zealand rabbits were submitted to general anesthesia and two perforations (2 mm) were made in each tibia for implantation of zinc-containing hydroxyapatite cylinders (left tibia) and hydroxyapatite cylinders (right tibia). After 1, 2 and 4 weeks, the animals were killed and one fragment of each tibia with the cylinder was collected and embedded in a methacrylate-based resin and cut into slices (approx200 {mu}m thickness), parallel to the implant's long axis with a precision diamond saw for Synchrotron Radiation X-ray Microfluorescence investigation. The accomplishment of the standard procedures helped the planning, execution and the comparative analysis of the results. The chemical and physical properties of the biomaterials were modified after its implantation and the incorporation of zinc. Both materials are biocompatible and promote osteoconduction and favored bone repair.

  19. 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.

  20. A New Method for the Detection of Galaxy Clusters in X-Ray Surveys

    SciTech Connect (OSTI)

    Piacentine, J.M.; Marshall, P.J.; Peterson, J.R.; Andersson, K.E.

    2005-01-01T23:59:59.000Z

    For many years the power of counting clusters of galaxies as a function of their mass has been recognized as a powerful cosmological probe; however, we are only now beginning to acquire data from dedicated surveys with sufcient sky coverage and sensitivity to measure the cluster population out to distances where the dark energy came to dominate the Universe’s evolution. One such survey uses the XMM X-ray telescope to scan a large area of sky, detecting the X-ray photons from the hot plasma that lies in the deep potential wells of massive clusters of galaxies. These clusters appear as extended (not point-like) objects, each providing just a few hundred photons in a typical observation. The detection of extended sources in such a low signal-to-noise situation is an important problem in astrophysics: we attempt to solve it by using as much prior information as possible, translating our experience with wellmeasured clusters to define a “template” cluster that can be varied and matched to the features seen in the XMM images. In this work we adapt an existing Monte Carlo analysis code for this problem. Two detection templates were dened and their suitability explored using simulated data; the method was then applied to a publically avalable XMM observation of a “blank” field. Presented are the encouraging results of this series of experiments, suggesting that this approach continue to be developed for future cluster-identication endeavours.

  1. Determination of Diffusion Profiles in Altered Wellbore Cement Using X-ray Computed Tomography Methods

    SciTech Connect (OSTI)

    Mason, Harris E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Walsh, Stuart D. C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); DuFrane, Wyatt L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Carroll, Susan A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2014-06-17T23:59:59.000Z

    The development of accurate, predictive models for use in determining wellbore integrity requires detailed information about the chemical and mechanical changes occurring in hardened Portland cements. X-ray computed tomography (XRCT) provides a method that can nondestructively probe these changes in three dimensions. Here, we describe a method for extracting subvoxel mineralogical and chemical information from synchrotron XRCT images by combining advanced image segmentation with geochemical models of cement alteration. The method relies on determining “effective linear activity coefficients” (ELAC) for the white light source to generate calibration curves that relate the image grayscales to material composition. The resulting data set supports the modeling of cement alteration by CO2-rich brine with discrete increases in calcium concentration at reaction boundaries. The results of these XRCT analyses can be used to further improve coupled geochemical and mechanical models of cement alteration in the wellbore environment.

  2. 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.

  3. Method for improve x-ray diffraction determinations of residual stress in nickel-base alloys

    DOE Patents [OSTI]

    Berman, Robert M. (Pittsburgh, PA); Cohen, Isadore (Pittsburgh, PA)

    1990-01-01T23:59:59.000Z

    A process for improving the technique of measuring residual stress by x-ray diffraction in pieces of nickel-base alloys which comprises covering part of a predetermined area of the surface of a nickel-base alloy with a dispersion, exposing the covered and uncovered portions of the surface of the alloy to x-rays by way of an x-ray diffractometry apparatus, making x-ray diffraction determinations of the exposed surface, and measuring the residual stress in the alloy based on these determinations. The dispersion is opaque to x-rays and serves a dual purpose since it masks off unsatisfactory signals such that only a small portion of the surface is measured, and it supplies an internal standard by providing diffractogram peaks comparable to the peaks of the nickel alloy so that the alloy peaks can be very accurately located regardless of any sources of error external to the sample.

  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. Standard test method for determination of uranium or gadolinium (or both) in gadolinium oxide-uranium oxide pellets or by X-ray fluorescence (XRF)

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2008-01-01T23:59:59.000Z

    Standard test method for determination of uranium or gadolinium (or both) in gadolinium oxide-uranium oxide pellets or by X-ray fluorescence (XRF)

  7. Method of determining the x-ray limit of an ion gauge

    DOE Patents [OSTI]

    Edwards, Jr., David (Bellport, NY); Lanni, Christopher P. (Shirley, NY)

    1981-01-01T23:59:59.000Z

    An ion gauge having a reduced "x-ray limit" and means for measuring that limit. The gauge comprises an ion gauge of the Bayard-Alpert type having a short collector and having means for varying the grid-collector voltage. The "x-ray limit" (i.e. the collector current resulting from x-rays striking the collector) may then be determined by the formula: ##EQU1## where: I.sub.x ="x-ray limit", I.sub.l and I.sub.h =the collector current at the lower and higher grid voltage respectively; and, .alpha.=the ratio of the collector current due to positive ions at the higher voltage to that at the lower voltage.

  8. Spectral encoding method for measuring the relative arrival time between x-ray/optical pulses

    SciTech Connect (OSTI)

    Bionta, M. R., E-mail: mina.bionta@irsamc.ups-tlse.fr [Université de Toulouse, UPS, Laboratoire Collisions Agrégats Réactivité, IRSAMC, F-31062 Toulouse (France); CNRS, UMR 5589, F-31062 Toulouse (France); The Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Hartmann, N. [The Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Institute of Applied Physics, University of Bern, Sidlerstr. 5, 3012 Bern (Switzerland); Weaver, M.; French, D.; Glownia, J. M.; Bostedt, C.; Chollet, M.; Ding, Y.; Fritz, D. M.; Fry, A. R.; Krzywinski, J.; Lemke, H. T.; Messerschmidt, M.; Schorb, S.; Zhu, D.; White, W. E. [The Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Nicholson, D. J. [The Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Department of Applied Physics, Stanford University, Stanford, California 94305 (United States); Cryan, J. P. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720 (United States); Baker, K. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551 (United States); Kane, D. J. [Mesa Photonics, LLC., 1550 Pacheco St., Santa Fe, New Mexico 87505 (United States); and others

    2014-08-15T23:59:59.000Z

    The advent of few femtosecond x-ray light sources brings promise of x-ray/optical pump-probe experiments that can measure chemical and structural changes in the 10–100 fs time regime. Widely distributed timing systems used at x-ray Free-Electron Laser facilities are typically limited to above 50 fs fwhm jitter in active x-ray/optical synchronization. The approach of single-shot timing measurements is used to sort results in the event processing stage. This has seen wide use to accommodate the insufficient precision of active stabilization schemes. In this article, we review the current technique for “measure-and-sort” at the Linac Coherent Light Source at the SLAC National Accelerator Laboratory. The relative arrival time between an x-ray pulse and an optical pulse is measured near the experimental interaction region as a spectrally encoded cross-correlation signal. The cross-correlation provides a time-stamp for filter-and-sort algorithms used for real-time sorting. Sub-10 fs rms resolution is common in this technique, placing timing precision at the same scale as the duration of the shortest achievable x-ray pulses.

  9. Start | View At a Glance | Author Index 220-1 Kinetics of Rapid Redox Processes at the Mineral/Water Interface Using Quick-Scanning X-Ray Absorption Spectroscopy

    E-Print Network [OSTI]

    Sparks, Donald L.

    at the Mineral/Water Interface Using Quick-Scanning X-Ray Absorption Spectroscopy (Q-XAS). See more from-situ synchrotron-based technique, quick scanning X-ray absorption spectroscopy (Q-XAS), at sub-second time scales

  10. Method and apparatus for analog signal conditioner for high speed, digital x-ray spectrometer

    DOE Patents [OSTI]

    Warburton, William K. (1300 Mills St., Menlo Park, CA 94025); Hubbard, Bradley (Santa Cruz, CA)

    1999-01-01T23:59:59.000Z

    A signal processing system which accepts input from an x-ray detector-preamplifier and produces a signal of reduced dynamic range for subsequent analog-to-digital conversion. The system conditions the input signal to reduce the number of bits required in the analog-to-digital converter by removing that part of the input signal which varies only slowly in time and retaining the amplitude of the pulses which carry information about the x-rays absorbed by the detector. The parameters controlling the signal conditioner's operation can be readily supplied in digital form, allowing it to be integrated into a feedback loop as part of a larger digital x-ray spectroscopy system.

  11. Spectral resolution for a five-element, filtered, x-ray detector array using the method of Backus and Gilbert

    SciTech Connect (OSTI)

    Fehl, D. L. [Sandia National Laboratories, Albuquerque, New Mexico 87185-1196 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185-1196 (United States); Biggs, F. [Sandia National Laboratories, Albuquerque, New Mexico 87185-1196 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185-1196 (United States); Chandler, G. A. [Sandia National Laboratories, Albuquerque, New Mexico 87185-1196 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185-1196 (United States); Stygar, W. A. [Sandia National Laboratories, Albuquerque, New Mexico 87185-1196 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185-1196 (United States)

    2000-08-01T23:59:59.000Z

    The generalized method of Backus and Gilbert (BG) is described and applied to the inverse problem of obtaining the spectrum from a five-channel, filtered array of x-ray detectors. This diagnostic is routinely fielded on the Z facility at Sandia National Laboratories to study soft x-ray photons ({approx}100-2300 eV), emitted by high density Z-pinch plasmas. The BG method defines spectral resolution limits on the system of response functions that are in good agreement with a classical unfold method, based on a histogram representation of the source spectrum. The resolution so defined is independent of the source spectrum. For noise-free, simulated data the BG approximating function is also in reasonable agreement with the source spectrum (150 eV blackbody) and the unfolded spectrum. This function may be used as an initial trial function for iterative methods or a regularization model.(c) 2000 American Institute of Physics. (c)

  12. Spectral Resolution for Five-Element, Filtered, X-Ray Detector (XRD) Arrays Using the Methods of Backus and Gilbert

    SciTech Connect (OSTI)

    FEHL,DAVID LEE; BIGGS,F.; CHANDLER,GORDON A.; STYGAR,WILLIAM A.

    2000-01-17T23:59:59.000Z

    The generalized method of Backus and Gilbert (BG) is described and applied to the inverse problem of obtaining spectra from a 5-channel, filtered array of x-ray detectors (XRD's). This diagnostic is routinely fielded on the Z facility at Sandia National Laboratories to study soft x-ray photons ({le}2300 eV), emitted by high density Z-pinch plasmas. The BG method defines spectral resolution limits on the system of response functions that are in good agreement with the unfold method currently in use. The resolution so defined is independent of the source spectrum. For noise-free, simulated data the BG approximating function is also in reasonable agreement with the source spectrum (150 eV black-body) and the unfold. This function may be used as an initial trial function for iterative methods or a regularization model.

  13. Systems and methods for detecting an image of an object by use of an X-ray beam having a polychromatic distribution

    DOE Patents [OSTI]

    Parham, Christopher; Zhong, Zhong; Pisano, Etta; Connor, Dean; Chapman, Leroy D.

    2010-06-22T23:59:59.000Z

    Systems and methods for detecting an image of an object using an X-ray beam having a polychromatic energy distribution are disclosed. According to one aspect, a method can include detecting an image of an object. The method can include generating a first X-ray beam having a polychromatic energy distribution. Further, the method can include positioning a single monochromator crystal in a predetermined position to directly intercept the first X-ray beam such that a second X-ray beam having a predetermined energy level is produced. Further, an object can be positioned in the path of the second X-ray beam for transmission of the second X-ray beam through the object and emission from the object as a transmitted X-ray beam. The transmitted X-ray beam can be directed at an angle of incidence upon a crystal analyzer. Further, an image of the object can be detected from a beam diffracted from the analyzer crystal.

  14. Method for characterizing mask defects using image reconstruction from X-ray diffraction patterns

    DOE Patents [OSTI]

    Hau-Riege, Stefan Peter (Fremont, CA)

    2007-05-01T23:59:59.000Z

    The invention applies techniques for image reconstruction from X-ray diffraction patterns on the three-dimensional imaging of defects in EUVL multilayer films. The reconstructed image gives information about the out-of-plane position and the diffraction strength of the defect. The positional information can be used to select the correct defect repair technique. This invention enables the fabrication of defect-free (since repaired) X-ray Mo--Si multilayer mirrors. Repairing Mo--Si multilayer-film defects on mask blanks is a key for the commercial success of EUVL. It is known that particles are added to the Mo--Si multilayer film during the fabrication process. There is a large effort to reduce this contamination, but results are not sufficient, and defects continue to be a major mask yield limiter. All suggested repair strategies need to know the out-of-plane position of the defects in the multilayer.

  15. The determination of interfacial structure and phase transitions in Al/Cu and Al/Ni interfaces by means of surface extended x-ray absorption fine structure

    SciTech Connect (OSTI)

    Barrera, E.V. (Rice Univ., Houston, TX (United States). Dept. of Mechanical Engineering and Materials Science); Heald, S.M. (Brookhaven National Lab., Upton, NY (United States))

    1991-01-01T23:59:59.000Z

    Surface extended x-ray absorption fine structure (SEXAFS) was used to investigate the interfacial conditions of Al/Cu and Al/Ni shallow buried interfaces. Previous studies using glancing angle extended x-ray absorption fine structure, x-ray reflectivity, photoemission, and SEXAFS produced conflicting results as to whether or not the interfaces between Al and Cu and Al and Ni were reacted upon room temperature deposition. In this study polycrystalline bilayers of Al/Cu and Al/Ni and trilayers of Al/Cu/Al and Al/Ni/Al were deposited on tantalum foil at room temperature in ultra high vacuum and analyzed to evaluate the reactivity of these systems on a nanometer scale. It become overwhelming apparent that the interfacial phase reactions were a function of the vacuum conditions. Samples deposited with the optimum vacuum conditions showed reaction products upon deposition at room temperature which were characterized by comparisons to standards and by least squares fitting the be CuAl{sub 2} and NiAl{sub 3} respectively. The results of this study that the reacted zone thicknesses were readily dependent on the deposition parameters. For both Al on Cu and Al on Ni as well as the metal on Al conditions 10{Angstrom} reaction zones were observed. These reaction zones were smaller than that observed for bilayers of Al on Cu (30{Angstrom}) and Al on Ni (60{Angstrom}) where deposition rates were much higher and samples were much thicker. The reaction species are evident by SEXAFS, where the previous photoemission studies only indicated that changes had occurred. Improved vacuum conditions as compared to the earlier experiments is primarily the reason reactions on deposition were seen in this study as compared to the earlier SEXAFS studies.

  16. The determination of interfacial structure and phase transitions in Al/Cu and Al/Ni interfaces by means of surface extended x-ray absorption fine structure

    SciTech Connect (OSTI)

    Barrera, E.V. [Rice Univ., Houston, TX (United States). Dept. of Mechanical Engineering and Materials Science; Heald, S.M. [Brookhaven National Lab., Upton, NY (United States)

    1991-12-31T23:59:59.000Z

    Surface extended x-ray absorption fine structure (SEXAFS) was used to investigate the interfacial conditions of Al/Cu and Al/Ni shallow buried interfaces. Previous studies using glancing angle extended x-ray absorption fine structure, x-ray reflectivity, photoemission, and SEXAFS produced conflicting results as to whether or not the interfaces between Al and Cu and Al and Ni were reacted upon room temperature deposition. In this study polycrystalline bilayers of Al/Cu and Al/Ni and trilayers of Al/Cu/Al and Al/Ni/Al were deposited on tantalum foil at room temperature in ultra high vacuum and analyzed to evaluate the reactivity of these systems on a nanometer scale. It become overwhelming apparent that the interfacial phase reactions were a function of the vacuum conditions. Samples deposited with the optimum vacuum conditions showed reaction products upon deposition at room temperature which were characterized by comparisons to standards and by least squares fitting the be CuAl{sub 2} and NiAl{sub 3} respectively. The results of this study that the reacted zone thicknesses were readily dependent on the deposition parameters. For both Al on Cu and Al on Ni as well as the metal on Al conditions 10{Angstrom} reaction zones were observed. These reaction zones were smaller than that observed for bilayers of Al on Cu (30{Angstrom}) and Al on Ni (60{Angstrom}) where deposition rates were much higher and samples were much thicker. The reaction species are evident by SEXAFS, where the previous photoemission studies only indicated that changes had occurred. Improved vacuum conditions as compared to the earlier experiments is primarily the reason reactions on deposition were seen in this study as compared to the earlier SEXAFS studies.

  17. Setup for in situ investigation of gases and gas/solid interfaces by soft x-ray emission and absorption spectroscopy

    SciTech Connect (OSTI)

    Benkert, A., E-mail: andreas.benkert@kit.edu, E-mail: l.weinhardt@kit.edu [Institute for Photon Science and Synchrotron Radiation, Karlsruhe Institute of Technology (KIT), Hermann-v.-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Universität Würzburg, Experimentelle Physik VII, Am Hubland, 97074 Würzburg (Germany); Gemeinschaftslabor für Nanoanalytik, Karlsruhe Institute of Technology (KIT), 76021 Karlsruhe (Germany); Blum, M. [Department of Chemistry, University of Nevada, Las Vegas (UNLV), 4505 Maryland Parkway, Nevada 89154-4003 (United States) [Department of Chemistry, University of Nevada, Las Vegas (UNLV), 4505 Maryland Parkway, Nevada 89154-4003 (United States); Advanced Light Source, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720 (United States); Meyer, F. [Universität Würzburg, Experimentelle Physik VII, Am Hubland, 97074 Würzburg (Germany)] [Universität Würzburg, Experimentelle Physik VII, Am Hubland, 97074 Würzburg (Germany); Wilks, R. G. [Solar Energy Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner-Platz 1, 14109 Berlin (Germany)] [Solar Energy Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Yang, W. [Advanced Light Source, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720 (United States)] [Advanced Light Source, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720 (United States); Bär, M. [Department of Chemistry, University of Nevada, Las Vegas (UNLV), 4505 Maryland Parkway, Nevada 89154-4003 (United States) [Department of Chemistry, University of Nevada, Las Vegas (UNLV), 4505 Maryland Parkway, Nevada 89154-4003 (United States); Solar Energy Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Insitut für Physik und Chemie, Brandenburgische Technische Universität Cottbus-Senftenberg, Konrad-Wachsmann-Allee 1, 03046 Cottbus (Germany); and others

    2014-01-15T23:59:59.000Z

    We present a novel gas cell designed to study the electronic structure of gases and gas/solid interfaces using soft x-ray emission and absorption spectroscopies. In this cell, the sample gas is separated from the vacuum of the analysis chamber by a thin window membrane, allowing in situ measurements under atmospheric pressure. The temperature of the gas can be regulated from room temperature up to approximately 600?°C. To avoid beam damage, a constant mass flow can be maintained to continuously refresh the gaseous sample. Furthermore, the gas cell provides space for solid-state samples, allowing to study the gas/solid interface for surface catalytic reactions at elevated temperatures. To demonstrate the capabilities of the cell, we have investigated a TiO{sub 2} sample behind a mixture of N{sub 2} and He gas at atmospheric pressure.

  18. 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.

  19. Determination of preferential molecular orientation in porphyrin-fullerene dyad ZnDHD6ee monolayers by the X-ray standing-wave method and X-ray reflectometry

    SciTech Connect (OSTI)

    Seregin, A. Yu., E-mail: seregin@gmail.com; D'yakova, Yu. A.; Yakunin, S. N.; Makhotkin, I. A. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)] [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation); Alekseev, A. S. [Russian Academy of Sciences, Prokhorov General Physics Institute (Russian Federation)] [Russian Academy of Sciences, Prokhorov General Physics Institute (Russian Federation); Klechkovskaya, V. V.; Tereschenko, E. Yu. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)] [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation); Tkachenko, N. V.; Lemmetyinen, H. [Tampere University of Technology (Finland)] [Tampere University of Technology (Finland); Feigin, L. A.; Kovalchuk, M. V. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)] [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)

    2013-11-15T23:59:59.000Z

    Monolayers of porphyrin-fullerene dyad molecules with zinc atoms incorporated into the porphyrin ring (ZnDHD6ee) on the surface of aqueous subphase and on Si substrates have been investigated by the X-ray standing-wave method and X-ray reflectometry. The experiments have been performed under laboratory conditions and on synchrotron radiation sources (KMC-2 station of BESSY II (Berlin) and Langmuir station at the National Research Centre 'Kurchatov Institute'). Depth distributions of Zn atoms and electron density in the monolayer film are calculated. On the basis of the analysis of these distributions, it is concluded that ZnDHD6ee dyad molecules in monolayers have preferential orientation. The data obtained indicate that the molecules in monolayer film retain their orientation when the monolayer is transferred from a liquid subphase surface onto a solid substrate.

  20. Use of X-Ray Absorption Spectroscopy to Monitor the Kinetics of Metal Sorption Reactions at the Soil/Water Interface

    E-Print Network [OSTI]

    Sparks, Donald L.

    Use of X-Ray Absorption Spectroscopy to Monitor the Kinetics of Metal Sorption Reactions on the surface coordination environment of Ni sorbed onto clays and aluminum oxides using X-ray absorption fine

  1. In operando observation system for electrochemical reaction by soft X-ray absorption spectroscopy with potential modulation method

    SciTech Connect (OSTI)

    Nagasaka, Masanari, E-mail: nagasaka@ims.ac.jp; Kosugi, Nobuhiro [Institute for Molecular Science, Myodaiji, Okazaki 444-8585 (Japan); The Graduate University for Advanced Studies, Myodaiji, Okazaki 444-8585 (Japan); Yuzawa, Hayato; Horigome, Toshio [Institute for Molecular Science, Myodaiji, Okazaki 444-8585 (Japan)

    2014-10-15T23:59:59.000Z

    In order to investigate local structures of electrolytes in electrochemical reactions under the same scan rate as a typical value 100 mV/s in cyclic voltammetry (CV), we have developed an in operando observation system for electrochemical reactions by soft X-ray absorption spectroscopy (XAS) with a potential modulation method. XAS spectra of electrolytes are measured by using a transmission-type liquid flow cell with built-in electrodes. The electrode potential is swept with a scan rate of 100 mV/s at a fixed photon energy, and soft X-ray absorption coefficients at different potentials are measured at the same time. By repeating the potential modulation at each fixed photon energy, it is possible to measure XAS of electrochemical reaction at the same scan rate as in CV. We have demonstrated successful measurement of the Fe L-edge XAS spectra of aqueous iron sulfate solutions and of the change in valence of Fe ions at different potentials in the Fe redox reaction. The mechanism of these Fe redox processes is discussed by correlating the XAS results with those at different scan rates.

  2. Methods for assisting recovery of damaged brain and spinal cord using arrays of X-Ray microplanar beams

    DOE Patents [OSTI]

    Dilmanian, F. Avraham (Yaphank, NY); McDonald, III, John W. (Baltimore, MD)

    2007-12-04T23:59:59.000Z

    A method of assisting recovery of an injury site of brain or spinal cord injury includes providing a therapeutic dose of X-ray radiation to the injury site through an array of parallel microplanar beams. The dose at least temporarily removes regeneration inhibitors from the irradiated regions. Substantially unirradiated cells surviving between the microplanar beams migrate to the in-beam irradiated portion and assist in recovery. The dose may be administered in dose fractions over several sessions, separated in time, using angle-variable intersecting microbeam arrays (AVIMA). Additional doses may be administered by varying the orientation of the microplanar beams. The method may be enhanced by injecting stem cells into the injury site.

  3. Methods for assisting recovery of damaged brain and spinal cord using arrays of X-ray microplanar beams

    DOE Patents [OSTI]

    Dilmanian, F. Avraham; McDonald, III, John W.

    2007-01-02T23:59:59.000Z

    A method of assisting recovery of an injury site of brain or spinal cord injury includes providing a therapeutic dose of X-ray radiation to the injury site through an array of parallel microplanar beams. The dose at least temporarily removes regeneration inhibitors from the irradiated regions. Substantially unirradiated cells surviving between the microplanar beams migrate to the in-beam irradiated portion and assist in recovery. The dose may be administered in dose fractions over several sessions, separated in time, using angle-variable intersecting microbeam arrays (AVIMA). Additional doses may be administered by varying the orientation of the microplanar beams. The method may be enhanced by injecting stem cells into the injury site.

  4. Determining the Dust Extinction of Gamma-ray Burst Host Galaxies: A Direct Method Based on Optical and X-ray Photometry

    E-Print Network [OSTI]

    Li, Yuan; Wei, Daming

    2007-01-01T23:59:59.000Z

    The dust extinction of gamma-ray bursts (GRBs) host galaxies, containing important clues to the nature of GRB progenitors and crucial for dereddening, is still poorly known. Here we propose a straightforward method to determine the extinction of GRB host galaxies by comparing the observed optical spectra to the intrinsic ones extrapolated from the X-ray spectra. The rationale for this method is from the standard fireball model: if the optical flux decay index equals to that of the X-ray flux, then there is no break frequency between the optical and X-ray bands, therefore we can derive the intrinsic optical flux from the X-ray spectra. We apply this method to three GRBs of which the optical and X-ray fluxes have the same decay indices and another one with inferred cooling break frequency, and obtain the rest-frame extinction curves of their host galaxies. The derived extinction curves are gray and do not resemble any extinction curves of local galaxies (e.g. the Milk Way, the Small/Large Magellanic Clouds, or ...

  5. Absolute x-ray energy calibration over a wide energy range using a diffraction-based iterative method

    E-Print Network [OSTI]

    Duffy, Thomas S.

    Mineral Physics Institute, Stony Brook University, Stony Brook, New York 11794, USA 2 DepartmentAbsolute x-ray energy calibration over a wide energy range using a diffraction-based iterative;REVIEW OF SCIENTIFIC INSTRUMENTS 83, 063901 (2012) Absolute x-ray energy calibration over a wide energy

  6. Determining the Dust Extinction of Gamma-ray Burst Host Galaxies: A Direct Method Based on Optical and X-ray Photometry

    E-Print Network [OSTI]

    Yuan Li; Aigen Li; Daming Wei

    2007-12-17T23:59:59.000Z

    The dust extinction of gamma-ray bursts (GRBs) host galaxies, containing important clues to the nature of GRB progenitors and crucial for dereddening, is still poorly known. Here we propose a straightforward method to determine the extinction of GRB host galaxies by comparing the observed optical spectra to the intrinsic ones extrapolated from the X-ray spectra. The rationale for this method is from the standard fireball model: if the optical flux decay index equals to that of the X-ray flux, then there is no break frequency between the optical and X-ray bands, therefore we can derive the intrinsic optical flux from the X-ray spectra. We apply this method to three GRBs of which the optical and X-ray fluxes have the same decay indices and another one with inferred cooling break frequency, and obtain the rest-frame extinction curves of their host galaxies. The derived extinction curves are gray and do not resemble any extinction curves of local galaxies (e.g. the Milk Way, the Small/Large Magellanic Clouds, or nearby starburst galaxies). The amount of extinction is rather large (with visual extinction $A_V$ $\\sim$ 1.6--3.4$\\magni$). We model the derived extinction curves in terms of the silicate-graphite interstellar grain model. As expected from the ``gray'' nature of the derived extinction curve, the dust size distribution is skewed to large grains. We determine, for the first time, the local dust-to-gas ratios of GRB host galaxies using the model-derived dust parameters and the hydrogen column densities determined from X-ray absorptions.

  7. 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.

  8. A theoretical comparison of x-ray angiographic image quality using energy-dependent and conventional subtraction methods

    SciTech Connect (OSTI)

    Tanguay, Jesse; Kim, Ho Kyung; Cunningham, Ian A. [Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, Ontario N6A 5K8 (Canada) and Department of Medical Biophysics, University of Western Ontario, London, Ontario N6A 5C1 (Canada); School of Mechanical Engineering, Pusan National University, Jangjeon-dong, Geumjeong-gu, Busan 609-735 (Korea, Republic of); Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, Ontario N6A 5K8 (Canada); Department of Medical Biophysics, University of Western Ontario, London, Ontario N6A 5C1 (Canada); Lawson Health Research Institute, London, Ontario N6A 4V2 (Canada) and London Health Sciences Centre, London, Ontario N6A 5A5 (Canada)

    2012-01-15T23:59:59.000Z

    Purpose: X-ray digital subtraction angiography (DSA) is widely used for vascular imaging. However, the need to subtract a mask image can result in motion artifacts and compromised image quality. The current interest in energy-resolving photon-counting (EPC) detectors offers the promise of eliminating motion artifacts and other advanced applications using a single exposure. The authors describe a method of assessing the iodine signal-to-noise ratio (SNR) that may be achieved with energy-resolved angiography (ERA) to enable a direct comparison with other approaches including DSA and dual-energy angiography for the same patient exposure. Methods: A linearized noise-propagation approach, combined with linear expressions of dual-energy and energy-resolved imaging, is used to describe the iodine SNR. The results were validated by a Monte Carlo calculation for all three approaches and compared visually for dual-energy and DSA imaging using a simple angiographic phantom with a CsI-based flat-panel detector. Results: The linearized SNR calculations show excellent agreement with Monte Carlo results. While dual-energy methods require an increased tube heat load of 2x to 4x compared to DSA, and photon-counting detectors are not yet ready for angiographic imaging, the available iodine SNR for both methods as tested is within 10% of that of conventional DSA for the same patient exposure over a wide range of patient thicknesses and iodine concentrations. Conclusions: While the energy-based methods are not necessarily optimized and further improvements are likely, the linearized noise-propagation analysis provides the theoretical framework of a level playing field for optimization studies and comparison with conventional DSA. It is concluded that both dual-energy and photon-counting approaches have the potential to provide similar angiographic image quality to DSA.

  9. 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.

  10. Shad-o-Snap X-Ray Camera Hardware Manual

    E-Print Network [OSTI]

    -o-Snap x-ray camera is a complete, stand-alone x-ray imaging device featuring "smart" microprocessor-controlled camera electronics and a convenient USB interface. The plug- and-play interface allows easy control by the silicon photodiodes. The Shad-o-Snap camera also includes electronics to digitize the video signal

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. Automated suppression of errors in LTP-II slope measurements with x-ray optics. Part1: Review of LTP errors and methods for the error reduction

    E-Print Network [OSTI]

    Ali, Zulfiqar

    2013-01-01T23:59:59.000Z

    267-70 (2001). 2. P. Z. Takacs, “X-ray optics metrology,” inHandbook of Optics, 3rd ed. , Vol. V , M. Bass, Ed. ,X-ray Grazing Incidence Optics for European XFEL: Analysis

  17. 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

  18. Method and apparatus for digitally based high speed x-ray spectrometer for direct coupled use with continuous discharge preamplifiers

    DOE Patents [OSTI]

    Warburton, William K. (1300 Mills St., Menlo Park, CA 94025)

    1998-01-01T23:59:59.000Z

    A high speed, digitally based, signal processing system which accepts directly coupled input data from a detector with a continuous discharge type preamplifier and produces a spectral analysis of the x-rays illuminating the detector. The system's principal elements are an analog signal conditioning section, a combinatorial logic section which implements digital triangular filtering and pileup inspection, and a microprocessor which accepts values captured by the logic section and uses them to compute x-ray energy values. Operating without pole-zero correction, the system achieves high resolution by capturing, in conjunction with each peak value from the digital filter, an associated value of the unfiltered signal, and using this latter signal to correct the former for errors which arise from its local slope terms. This correction greatly reduces both energy resolution degradation and peak centroid shifting in the output spectrum as a function of input count rate. When the noise of this correction is excessive, a modification allows two filtered averages of the signal to be captured and a corrected peak amplitude computed therefrom.

  19. Method and apparatus for digitally based high speed x-ray spectrometer for direct coupled use with continuous discharge preamplifiers

    DOE Patents [OSTI]

    Warburton, W.K.

    1998-06-30T23:59:59.000Z

    A high speed, digitally based, signal processing system is disclosed which accepts directly coupled input data from a detector with a continuous discharge type preamplifier and produces a spectral analysis of the x-rays illuminating the detector. The system`s principal elements are an analog signal conditioning section, a combinatorial logic section which implements digital triangular filtering and pileup inspection, and a microprocessor which accepts values captured by the logic section and uses them to compute x-ray energy values. Operating without pole-zero correction, the system achieves high resolution by capturing, in conjunction with each peak value from the digital filter, an associated value of the unfiltered signal, and using this latter signal to correct the former for errors which arise from its local slope terms. This correction greatly reduces both energy resolution degradation and peak centroid shifting in the output spectrum as a function of input count rate. When the noise of this correction is excessive, a modification allows two filtered averages of the signal to be captured and a corrected peak amplitude computed therefrom. 14 figs.

  20. The X-ray crystal structure of Shewanella oneidensis OmcA reveals new insight at the microbe-mineral interface

    SciTech Connect (OSTI)

    Edwards, Marcus; Baiden, Nanakow; Johs, Alexander; Tomanicek, Stephen J.; Liang, Liyuan; Shi, Liang; Fredrickson, Jim K.; Zachara, John M.; Gates, Andrew J.; Butt, Julea N.; Richardson, David; Clarke, Thomas A.

    2014-05-21T23:59:59.000Z

    The x-ray crystal structure of Shewanella oneidensis OmcA, an extracellular decaheme cytochrome involved in mineral reduction, was solved to a resolution of 2.7 Å. The four OmcA molecules in the asymmetric unit were arranged so the distance between heme-5 on adjacent OmcA monomers was less than 1 nm, indicative of a transient OmcA dimer capable of intermolecular electron transfer. A previously identified hematite binding motif was identified near heme 10, forming a hydroxylated surface that would bring a heme-10 electron egress site to ~ 1 nm of mineral surface.

  1. State-Dependent Electron Delocalization Dynamics at the Solute-Solvent Interface: Soft X-ray Absorption Spectroscopy and Ab Initio Calculations

    E-Print Network [OSTI]

    Bokarev, Sergey I; Suljoti, Edlira; Kühn, Oliver; Aziz, Emad F

    2013-01-01T23:59:59.000Z

    Non-radiative decay channels in the L-edge fluorescence spectra from transition metal-aqueous solutions give rise to spectral dips in X-ray transmission spectra. Their origin is unraveled here using partial and inverse partial fluorescence yields on the micro-jet combined with multi-reference ab initio electronic structure calculations. Comparing Fe2+, Fe3+, and Co2+ systems we demonstrate unequivocally that spectral dips are due to a state-dependent electron delocalization within the manifold of d-orbitals.

  2. Method and apparatus for combinatorial logic signal processor in a digitally based high speed x-ray spectrometer

    DOE Patents [OSTI]

    Warburton, William K. (1300 Mills St., Menlo Park, CA 94025); Zhou, Zhiquing (Carl) (Fremont, CA)

    1999-01-01T23:59:59.000Z

    A high speed, digitally based, signal processing system which accepts a digitized input signal and detects the presence of step-like pulses in the this data stream, extracts filtered estimates of their amplitudes, inspects for pulse pileup, and records input pulse rates and system livetime. The system has two parallel processing channels: a slow channel, which filters the data stream with a long time constant trapezoidal filter for good energy resolution; and a fast channel which filters the data stream with a short time constant trapezoidal filter, detects pulses, inspects for pileups, and captures peak values from the slow channel for good events. The presence of a simple digital interface allows the system to be easily integrated with a digital processor to produce accurate spectra at high count rates and allow all spectrometer functions to be fully automated. Because the method is digitally based, it allows pulses to be binned based on time related values, as well as on their amplitudes, if desired.

  3. Method and apparatus for combinatorial logic signal processor in a digitally based high speed x-ray spectrometer

    DOE Patents [OSTI]

    Warburton, W.K.

    1999-02-16T23:59:59.000Z

    A high speed, digitally based, signal processing system is disclosed which accepts a digitized input signal and detects the presence of step-like pulses in the this data stream, extracts filtered estimates of their amplitudes, inspects for pulse pileup, and records input pulse rates and system lifetime. The system has two parallel processing channels: a slow channel, which filters the data stream with a long time constant trapezoidal filter for good energy resolution; and a fast channel which filters the data stream with a short time constant trapezoidal filter, detects pulses, inspects for pileups, and captures peak values from the slow channel for good events. The presence of a simple digital interface allows the system to be easily integrated with a digital processor to produce accurate spectra at high count rates and allow all spectrometer functions to be fully automated. Because the method is digitally based, it allows pulses to be binned based on time related values, as well as on their amplitudes, if desired. 31 figs.

  4. Methods for assisting recovery of damaged brain and spinal cord and treating various diseases using arrays of x-ray microplanar beams

    DOE Patents [OSTI]

    Dilmanian, F. Avraham (Yaphank, NY); Anchel, David J. (Rocky Point, NY); Gaudette, Glenn (Holden, MA); Romanelli, Pantaleo (Monteroduni, IT); Hainfeld, James (Shoreham, NY)

    2010-06-29T23:59:59.000Z

    A method of assisting recovery of an injury site of the central nervous system (CNS) or treating a disease includes providing a therapeutic dose of X-ray radiation to a target volume through an array of parallel microplanar beams. The dose to treat CNS injury temporarily removes regeneration inhibitors from the irradiated site. Substantially unirradiated cells surviving between beams migrate to the in-beam portion and assist recovery. The dose may be staggered in fractions over sessions using angle-variable intersecting microbeam arrays (AVIMA). Additional doses are administered by varying the orientation of the beams. The method is enhanced by injecting stem cells into the injury site. One array or the AVIMA method is applied to ablate selected cells in a target volume associated with disease for palliative or curative effect. Atrial fibrillation is treated by irradiating the atrial wall to destroy myocardial cells while continuously rotating the subject.

  5. ITAR: A modified TAR method to determine depth dose distribution for an ophthalmic device that performs kilovoltage x-ray pencil-beam stereotaxy

    SciTech Connect (OSTI)

    Hanlon, Justin, E-mail: jhanlon@orayainc.com; Chell, Erik; Firpo, Michael; Koruga, Igor [Oraya Therapeutics, Inc., Newark, California 94560 (United States)] [Oraya Therapeutics, Inc., Newark, California 94560 (United States)

    2014-02-15T23:59:59.000Z

    Purpose: New technology has been developed to treat age-related macular degeneration (AMD) using 100 kVp pencil-beams that enter the patient through the radio-resistant sclera with a depth of interest between 1.6 and 2.6 cm. Measurement of reference and relative dose in a kilovoltage x-ray beam with a 0.42 cm diameter field size and a 15 cm source to axis distance (SAD) is a challenge that is not fully addressed in current guidelines to medical physicists. AAPM's TG-61 gives dosimetry recommendations for low and medium energy x-rays, but not all of them are feasible to follow for this modality. Methods: An investigation was conducted to select appropriate equipment for the application. PTW's Type 34013 Soft X-Ray Chamber (Freiburg, Germany) and CIRS's Plastic Water LR (Norfolk, VA) were found to be the best available options. Attenuation curves were measured with minimal scatter contribution and thus called Low Scatter Tissue Air Ratio (LSTAR). A scatter conversion coefficient (C{sub scat}) was derived through Monte Carlo radiation transport simulation using MCNPX (LANL, Los Alamos, NM) to quantify the difference between a traditional TAR curve and the LSTAR curve. A material conversion coefficient (C{sub mat}) was determined through experimentation to evaluate the difference in attenuation properties between water and Plastic Water LR. Validity of performing direct dosimetry measurements with a source to detector distance other than the treatment distance, and therefore a different field size due to a fixed collimator, was explored. A method—Integrated Tissue Air Ratio (ITAR)—has been developed that isolates each of the three main radiological effects (distance from source, attenuation, and scatter) during measurement, and integrates them to determine the dose rate to the macula during treatment. Results: LSTAR curves were determined to be field size independent within the range explored, indicating that direct dosimetry measurements may be performed with a source to detector distance of 20 cm even though the SAD is 15 cm during treatment. C{sub scat} varied from 1.102 to 1.106 within the range of depths of interest. The experimental variance among repeated measurements of C{sub mat} was larger than depth dependence, so C{sub mat} was estimated as1.019 for all depths of interest. Conclusions: Equipment selection, measurement techniques, and formalism for the determination of dose rate to the macula during stereotaxy for AMD have been determined and are strongly recommended by the authors of this paper to be used by clinical medical physicists.

  6. 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.

  7. Spatially resolved energy dispersive x-ray spectroscopic method for in-situ evaluation of mechanical properties during the growth of a C - Pt composite nanowire

    SciTech Connect (OSTI)

    Banerjee, Amit; Banerjee, S. S., E-mail: satyajit@iitk.ac.in [Department of Physics, Indian Institute of Technology Kanpur, Kanpur, 208016 (India)

    2014-05-15T23:59:59.000Z

    A core-shell type C-Pt composite nanowire is fabricated using focused ion and electron beam induced chemical vapor deposition techniques. Using information from spatially resolved energy dispersive x-ray spectra, we detect the resonance vibration in the C-Pt composite nanowire. We use this method to measure the Young's moduli of the constituents (C, Pt) of the composite nanowire and also estimate the density of the FEB CVD grown Pt shell surrounding the C core. By measuring the resonance characteristics of the composite nanowire we estimate a Pt shell growth rate of ?0.9 nms{sup ?1}. The study is analyzed to suggest that the Pt shell growth mechanism is primarily governed by the sticking coefficient of the organometallic vapor on the C nanowire core.

  8. 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.

  9. 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.

  10. Quantification of thin film crystallographic orientation using X-ray diffraction with an area detector

    E-Print Network [OSTI]

    Baker, Jessica L

    2010-01-01T23:59:59.000Z

    elastic  properties of Au thin films by X?ray diffraction interface in  polythiophene thin?film transistors.  Nat copper  phthalocyanine thin films evaporated on amorphous 

  11. 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.

  12. 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.

  13. 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.

  14. Characterization of a Fe/Y[subscript 2]O[subscript 3] metal/oxide interface using neutron and x-ray scattering

    E-Print Network [OSTI]

    Watkins, E. B.

    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[subscript ...

  15. 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.

  16. X-ray compass for determining device orientation

    DOE Patents [OSTI]

    Da Silva, Luiz B. (Danville, CA); Matthews, Dennis L. (Moss Beach, CA); Fitch, Joseph P. (Livermore, CA); Everett, Matthew J. (Pleasanton, CA); Colston, Billy W. (Livermore, CA); Stone, Gary F. (Livermore, CA)

    1999-01-01T23:59:59.000Z

    An apparatus and method for determining the orientation of a device with respect to an x-ray source. In one embodiment, the present invention is coupled to a medical device in order to determine the rotational orientation of the medical device with respect to the x-ray source. In such an embodiment, the present invention is comprised of a scintillator portion which is adapted to emit photons upon the absorption of x-rays emitted from the x-ray source. An x-ray blocking portion is coupled to the scintillator portion. The x-ray blocking portion is disposed so as to vary the quantity of x-rays which penetrate the scintillator portion based upon the particular rotational orientation of the medical device with respect to the x-ray source. A photon transport mechanism is also coupled to the scintillator portion. The photon transport mechanism is adapted to pass the photons emitted from the scintillator portion to an electronics portion. By analyzing the quantity of the photons, the electronics portion determines the rotational orientation of the medical device with respect to the x-ray source.

  17. X-ray compass for determining device orientation

    DOE Patents [OSTI]

    Da Silva, L.B.; Matthews, D.L.; Fitch, J.P.; Everett, M.J.; Colston, B.W.; Stone, G.F.

    1999-06-15T23:59:59.000Z

    An apparatus and method for determining the orientation of a device with respect to an x-ray source are disclosed. In one embodiment, the present invention is coupled to a medical device in order to determine the rotational orientation of the medical device with respect to the x-ray source. In such an embodiment, the present invention is comprised of a scintillator portion which is adapted to emit photons upon the absorption of x-rays emitted from the x-ray source. An x-ray blocking portion is coupled to the scintillator portion. The x-ray blocking portion is disposed so as to vary the quantity of x-rays which penetrate the scintillator portion based upon the particular rotational orientation of the medical device with respect to the x-ray source. A photon transport mechanism is also coupled to the scintillator portion. The photon transport mechanism is adapted to pass the photons emitted from the scintillator portion to an electronics portion. By analyzing the quantity of the photons, the electronics portion determines the rotational orientation of the medical device with respect to the x-ray source. 25 figs.

  18. 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.

  19. 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.

  20. A study of structural transition in nanocrystalline titania thin films by X-ray diffraction Rietveld method

    SciTech Connect (OSTI)

    Murugesan, S. [Materials Synthesis and Structural Characterisation Section, Physical Metallurgy Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India)] [Materials Synthesis and Structural Characterisation Section, Physical Metallurgy Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India); Padhy, N. [Corrosion Science and Technology Division, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India)] [Corrosion Science and Technology Division, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India); Kuppusami, P., E-mail: pk@igcar.gov.in [Materials Synthesis and Structural Characterisation Section, Physical Metallurgy Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India); Mudali, U. Kamachi [Corrosion Science and Technology Division, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India)] [Corrosion Science and Technology Division, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India); Mohandas, E. [Materials Synthesis and Structural Characterisation Section, Physical Metallurgy Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India)] [Materials Synthesis and Structural Characterisation Section, Physical Metallurgy Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India)

    2010-12-15T23:59:59.000Z

    Structural and microstructural analyses of nanocrystalline titania thin films prepared by pulsed laser deposition have been carried out. At lower oxygen partial pressures ({<=}10{sup -4} mbar), rutile films were formed, whereas at 1.2 x 10{sup -3} mbar of oxygen partial pressure, the thin films contained both rutile and anatase phases. At 0.04 and 0.05 mbar of oxygen partial pressure, the film was purely anatase. Addition of oxygen has also shown a profound influence on the surface morphology of the as deposited titania films. Modified Rietveld method has been used to determine crystallite size, root mean square strain and fractional coordinates of oxygen of the anatase films. The influence of crystallite size and strain on the rutile to anatase phase transition is investigated.

  1. 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.

  2. The X-ray Power Density Spectrum of the Seyfert 2 Galaxy NGC 4945: Analysis and Application of the Method of Light Curve Simulations

    SciTech Connect (OSTI)

    Mueller, Martin; /SLAC

    2010-12-16T23:59:59.000Z

    The study of the power density spectrum (PDS) of fluctuations in the X-ray flux from active galactic nuclei (AGN) complements spectral studies in giving us a view into the processes operating in accreting compact objects. An important line of investigation is the comparison of the PDS from AGN with those from galactic black hole binaries; a related area of focus is the scaling relation between time scales for the variability and the black hole mass. The PDS of AGN is traditionally modeled using segments of power laws joined together at so-called break frequencies; associations of the break time scales, i.e., the inverses of the break frequencies, with time scales of physical processes thought to operate in these sources are then sought. I analyze the Method of Light Curve Simulations that is commonly used to characterize the PDS in AGN with a view to making the method as sensitive as possible to the shape of the PDS. I identify several weaknesses in the current implementation of the method and propose alternatives that can substitute for some of the key steps in the method. I focus on the complications introduced by uneven sampling in the light curve, the development of a fit statistic that is better matched to the distributions of power in the PDS, and the statistical evaluation of the fit between the observed data and the model for the PDS. Using archival data on one AGN, NGC 3516, I validate my changes against previously reported results. I also report new results on the PDS in NGC 4945, a Seyfert 2 galaxy with a well-determined black hole mass. This source provides an opportunity to investigate whether the PDS of Seyfert 1 and Seyfert 2 galaxies differ. It is also an attractive object for placement on the black hole mass-break time scale relation. Unfortunately, with the available data on NGC 4945, significant uncertainties on the break frequency in its PDS remain.

  3. 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.

  4. X-ray lasers and methods utilizing two component driving illumination provided by optical laser means of relatively low energy and small physical size

    DOE Patents [OSTI]

    Rosen, Mordecai D. (Berkeley, CA); Matthews, Dennis L. (El Granada, CA)

    1991-01-01T23:59:59.000Z

    An X-ray laser (10), and related methodology, are disclosed wherein an X-ray laser target (12) is illuminated with a first pulse of optical laser radiation (14) of relatively long duration having scarcely enough energy to produce a narrow and linear cool plasma of uniform composition (38). A second, relatively short pulse of optical laser radiation (18) is uniformly swept across the length, from end to end, of the plasma (38), at about the speed of light, to consecutively illuminate continuously succeeding portions of the plasma (38) with optical laser radiation having scarcely enough energy to heat, ionize, and invert them into the continuously succeeding portions of an X-ray gain medium. This inventive double pulse technique results in a saving of more than two orders of magnitude in driving optical laser energy, when compared to the conventional single pulse approach.

  5. Automated suppression of errors in LTP-II slope measurements with x-ray optics

    E-Print Network [OSTI]

    Ali, Zulfiqar

    2012-01-01T23:59:59.000Z

    precise reflective X-ray optics,” Nucl. Instrum. and Methods70 (2001). [2] P. Z. Takacs, “X- ray optics metrology,” in [Handbook of Optics], 3rd ed. , Vol. V, M. Bass, Ed. ,

  6. Use of soft x-ray diagnostic on the COMPASS tokamak for investigations of sawteeth crash neighborhood and of plasma position using fast inversion methods

    SciTech Connect (OSTI)

    Imrisek, M. [Institute of Plasma Physics ASCR, Prague (Czech Republic); Faculty of Mathematics and Physics, Charles University in Prague, Prague (Czech Republic); Weinzettl, V.; Mlynar, J.; Panek, R.; Hron, M. [Institute of Plasma Physics ASCR, Prague (Czech Republic); Odstrcil, T. [Max-Planck-Institut für Plasmaphysik, Garching (Germany); Odstrcil, M. [Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Prague (Czech Republic); Optical Research Center, University of Southampton, Southampton (United Kingdom); Ficker, O. [Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Prague (Czech Republic); Pinzon, J. R. [Institue Jean Lamour, Université de Lorraine, Nancy (France); Ehrlacher, C. [ENS Cachan, Paris (France)

    2014-11-15T23:59:59.000Z

    The soft x-ray diagnostic is suitable for monitoring plasma activity in the tokamak core, e.g., sawtooth instability. Moreover, spatially resolved measurements can provide information about plasma position and shape, which can supplement magnetic measurements. In this contribution, fast algorithms with the potential for a real-time use are tested on the data from the COMPASS tokamak. In addition, the soft x-ray data are compared with data from other diagnostics in order to discuss possible connection between sawtooth instability on one side and the transition to higher confinement mode, edge localized modes and productions of runaway electrons on the other side.

  7. High resolution energy-sensitive digital X-ray

    DOE Patents [OSTI]

    Nygren, David R. (Berkeley, CA)

    1995-01-01T23:59:59.000Z

    An apparatus and method for detecting an x-ray and for determining the depth of penetration of an x-ray into a semiconductor strip detector. In one embodiment, a semiconductor strip detector formed of semiconductor material is disposed in an edge-on orientation towards an x-ray source such that x-rays From the x-ray source are incident upon and substantially perpendicular to the front edge of the semiconductor strip detector. The semiconductor strip detector is formed of a plurality of segments. The segments are coupled together in a collinear arrangement such that the semiconductor strip detector has a length great enough such that substantially all of the x-rays incident on the front edge of the semiconductor strip detector interact with the semiconductor material which forms the semiconductor strip detector. A plurality of electrodes are connected to the semiconductor strip detect or such that each one of the of semiconductor strip detector segments has at least one of the of electrodes coupled thereto. A signal processor is also coupled to each one of the electrodes. The present detector detects an interaction within the semiconductor strip detector, between an x-ray and the semiconductor material, and also indicates the depth of penetration of the x-ray into the semiconductor strip detector at the time of the interaction.

  8. Measurement and characterization of x-ray spot size

    SciTech Connect (OSTI)

    Mueller, K.H.

    1989-01-01T23:59:59.000Z

    In planning an x-ray imaging experiment one must have an accurate model of the imaging system to obtain optimum results. The blurring caused by the finite size of the x-ray source is often the least understood element in the system. We have developed experimental and analytical methods permitting accurate measurement and modeling of the x-ray source. The model offers a simple and accurate way to optimize the radiographic geometry for any given experimental requirement (i.e., resolution and dose at detector). Any text on radiography will mention the effects of the finite size of the x-ray source on image quality and how one can minimize this influence by the choice of a small radiographic magnification. The film blur (independent of the source blur) is often treated as a single number and combined with an effective blur dimension for the x-ray source to give a total blur on the film. In this paper, we will develop a treatment of x-ray sources based on the modulation transfer function (MTF). This approach allows us to infer the spatial distribution function of the electron beam that produces the bremsstrahlung x-rays and to predict the performance of an x-ray imaging system if we know the MTF of the detector. This treatment is much more accurate than a single number characterization. 4 refs., 7 figs.

  9. Maximum Entropy Method and Charge Flipping, a Powerful Combination to Visualize the True Nature of Structural Disorder from in situ X-ray Powder Diffraction Data

    SciTech Connect (OSTI)

    Samy, A.; Dinnebier, R; van Smaalen, S; Jansen, M

    2010-01-01T23:59:59.000Z

    In a systematic approach, the ability of the Maximum Entropy Method (MEM) to reconstruct the most probable electron density of highly disordered crystal structures from X-ray powder diffraction data was evaluated. As a case study, the ambient temperature crystal structures of disordered {alpha}-Rb{sub 2}[C{sub 2}O{sub 4}] and {alpha}-Rb{sub 2}[CO{sub 3}] and ordered {delta}-K{sub 2}[C{sub 2}O{sub 4}] were investigated in detail with the aim of revealing the 'true' nature of the apparent disorder. Different combinations of F (based on phased structure factors) and G constraints (based on structure-factor amplitudes) from different sources were applied in MEM calculations. In particular, a new combination of the MEM with the recently developed charge-flipping algorithm with histogram matching for powder diffraction data (pCF) was successfully introduced to avoid the inevitable bias of the phases of the structure-factor amplitudes by the Rietveld model. Completely ab initio electron-density distributions have been obtained with the MEM applied to a combination of structure-factor amplitudes from Le Bail fits with phases derived from pCF. All features of the crystal structures, in particular the disorder of the oxalate and carbonate anions, and the displacements of the cations, are clearly obtained. This approach bears the potential of a fast method of electron-density determination, even for highly disordered materials. All the MEM maps obtained in this work were compared with the MEM map derived from the best Rietveld refined model. In general, the phased observed structure factors obtained from Rietveld refinement (applying F and G constraints) were found to give the closest description of the experimental data and thus lead to the most accurate image of the actual disorder.

  10. X-rays at Solid-Liquid Surfaces

    SciTech Connect (OSTI)

    Dosch, Helmut (Max Planck Institute for Metals Research) [Max Planck Institute for Metals Research

    2007-05-02T23:59:59.000Z

    Solid-liquid interfaces play an important role in many areas of current and future technologies, and in our biosphere. They play a key role in the development of nanofluidics and nanotribology, which sensitively depend on our knowledge of the microscopic structures and phenomena at the solid-liquid interface. The detailed understanding of how a fluid meets a wall is also a theoretical challenge. In particular, the phenomena at repulsive walls are of interest, since they affect many different phenomena, such as water-repellent surfaces or the role of the hydrophobic interaction in protein folding. Recent x-ray reflectivity studies of various solid-liquid interfaces have disclosed rather intriguiing phenomena, which will be discussed in this lecture: premelting of ice in contact with silica; liquid Pb in contact with Si; water in contact with hydrophobic surfaces. These experiments, carried out with high-energy x-ray microbeams, reveal detailed insight into the liquid density profile closest to the wall. A detailed insight into atomistic phenomena at solid-liquid interfaces is also a prerequisite in the microscopic control of electrochemical reactions at interfaces. Recent x-ray studies show the enormous future potential of such non-destructive analytical tools for the in situ observation of (electro-)chemical surface reactions. This lecture will review recent x-ray experiments on solid-liquid interfaces.

  11. Nuclear Instruments and Methods in Physics Research A 514 (2003) 206214 A silicon strip detector coupled to the RX64 ASIC for X-ray

    E-Print Network [OSTI]

    Ramello, Luciano

    2003-01-01T23:59:59.000Z

    , such as mammography and angiography at the iodine K-edge, the dual energy technique [3] makes it possible to isolate. The system is capable of single photon counting in digital X-ray imaging, with possible applications to dual energy mammography and angiography. The main features of the detecting system are low noise, good spatial

  12. 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.

  13. 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.

  14. Characterization of X-ray generator beam profiles.

    SciTech Connect (OSTI)

    Mitchell, Dean J; Harding, Lee T.; Thoreson, Gregory G.; Theisen, Lisa Anne; Parmeter, John Ethan; Thompson, Kyle Richard

    2013-07-01T23:59:59.000Z

    T to compute the radiography properties of various materials, the flux profiles of X-ray sources must be characterized. This report describes the characterization of X-ray beam profiles from a Kimtron industrial 450 kVp radiography system with a Comet MXC-45 HP/11 bipolar oil-cooled X-ray tube. The empirical method described here uses a detector response function to derive photon flux profiles based on data collected with a small cadmium telluride detector. The flux profiles are then reduced to a simple parametric form that enables computation of beam profiles for arbitrary accelerator energies.

  15. 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.

  16. 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.

  17. Note: A novel normalization scheme for laser-based plasma x-ray sources

    SciTech Connect (OSTI)

    Zhang, B. B.; Sun, D. R.; Tao, Y., E-mail: taoy@ihep.ac.cn [Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Sun, S. S. [Institute of Physics, Chinese Academy of Sciences, Beijing 100090 (China)

    2014-09-15T23:59:59.000Z

    A kHz repetition rate laser pump-X-ray probe system for ultrafast X-ray diffraction is set up based on a laser-driven plasma X-ray source. A simple and reliable normalization approach has been developed to minimize the impact of large X-ray pulse intensity fluctuation on data quality. It utilizes one single X-ray area detector to record both sample and reference signals simultaneously. Performance of this novel normalization method is demonstrated in reflectivity oscillation measurement of a superlattice sample at sub-ps resolution.

  18. 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.

  19. 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.

  20. Immersed interface methods. Progress report

    SciTech Connect (OSTI)

    LeVeque, R.J.; Adams, L.M.; Bube, K.P.

    1997-06-09T23:59:59.000Z

    Short summaries are given for the following related projects: Multigrid methods for Poisson problems; Domain embedding; Groundwater flow; Solidification; The explicit jump IIM and conductivity inverse problems; Numerical methods for acoustic and visco-acoustic inverse problems; Finite element version of the IIM; Computation of seismic traveltimes in discontinuous media; and CLAWPACK (Conservation LAWs PACKage) and AMRCLAW (Adaptive Mesh Refinement CLAW).

  1. 54X-rays from Hot Gases Near the SN1979C Black Hole The Chandra X-Ray Observatory

    E-Print Network [OSTI]

    is in solar mass units, and R is in kilometers. Problem 1 - Combining these equations using the method-Newton and the German ROSAT observatory revealed a bright source of X-rays that has remained steady for the 12 years, or distribution of X-rays with energy, support the idea that the object in SN 1979C is a black hole being fed

  2. 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.

  3. 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.

  4. 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...

  5. 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...

  6. 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), ...

  7. 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.

  8. 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.

  9. 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.

  10. The color of X-rays Spectral X-ray computed tomography using energy sensitive pixel detectors

    E-Print Network [OSTI]

    Schioppa, Enrico Junior

    Energy sensitive X-ray imaging detectors are produced by connecting a semiconductor sensor to a spectroscopic pixel readout chip. In this thesis, the applicability of such detectors to X-ray Computed Tomography (CT) is studied. A prototype Medipix based silicon detector is calibrated using X-ray fluorescence. The charge transport properties of the sensor are characterized using a high energy beam of charged particles at the Super Proton Synchrotron (SPS) at the European Center for Nuclear Research (CERN). Monochromatic X-rays at the European Synchrotron Radiation Facility (ESRF) are used to determined the energy response function. These data are used to implement a physics-based CT projection operator that accounts for the transmission of the source spectrum through the sample and detector effects. Based on this projection operator, an iterative spectral CT reconstruction algorithm is developed by extending an Ordered Subset Expectation Maximization (OSEM) method. Subsequently, a maximum likelihood based algo...

  11. 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...

  12. 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 ...

  13. 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

  14. 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

  15. 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.

  16. Reliable before-fabrication forecasting of expected surface slope distributions for x-ray optics

    E-Print Network [OSTI]

    Yashchuk, Yekaterina V.

    2013-01-01T23:59:59.000Z

    of x-ray optics for the LCLS free-electron laser,” Proc.beamlines and diagnostics at LCLS,” Nucl. Instrum. Methods A

  17. AUTOMATED ELEMENTAL ANALYSIS USING ENERGY DISPERSIVE X-RAY FLUORESCENCE ANALYSIS

    E-Print Network [OSTI]

    Jaklevic, J.M.

    2011-01-01T23:59:59.000Z

    upon the x-ray fluorescence (XRF) method for the elementalnon-destructive nature of XRF is especially important whereconcentrations are measured in the XRF spectrometer and the

  18. 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.

  19. 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.

  20. 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

  1. 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.

  2. 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.

  3. Confocal X-ray Fluorescence (XRF) Microscopy: A New Technique for the Nondestructive Compositional Depth Profiling of Paintings

    E-Print Network [OSTI]

    Gruner, Sol M.

    #12;Confocal X-ray Fluorescence (XRF) Microscopy: A New Technique for the Nondestructive tools such as x-ray fluorescence (XRF) [4,5,6,7] and proton-induced x-ray emission (PIXE) [3,8,9] to address the problem of compositional depth profiling of paintings. One XRF method consists of deducing

  4. Combined electrophoresis-electrospray interface and method

    DOE Patents [OSTI]

    Smith, R.D.; Udseth, H.R.; Barinaga, C.J.

    1995-06-13T23:59:59.000Z

    An improvement to the system and method is disclosed for analyzing molecular constituents of a composition sample that comprises improvements to an electrospray ionization source for interfacing to mass spectrometers and other detection devices. The improvement consists of establishing a unique electrical circuit pattern and nozzle configuration, a metallic coated and conical shaped capillary outlet, coupled with sizing of the capillary to obtain maximum sensitivity. 10 figs.

  5. Biological imaging by soft x-ray diffraction microscopy

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

    Shapiro, D. [Stony Brook Univ., Stony Brook, NY (United States); Thibault, P. [Cornell Univ., Ithaca, NY (United States); Beetz, T. [Stony Brook Univ., Stony Brook, NY (United States); Brookhaven National Lab., Upton, NY (United States). Center for Functional Nanomaterials; Elser, V. [Cornell Univ., Ithaca, NY (United States); Howells, M. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source; Jacobsen, C. [Stony Brook Univ., Stony Brook, NY (United States); Brookhaven National Lab., Upton, NY (United States). Center for Functional Nanomaterials; Kirz, J. [Stony Brook Univ., Stony Brook, NY (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source; Lima, E. [Stony Brook Univ., Stony Brook, NY (United States); Miao, H. [Stony Brook Univ., Stony Brook, NY (United States); Neiman, A. M. [State Univ. of New York at Stony Brook, NY (United States); Sayre, D. [Stony Brook Univ., Stony Brook, NY (United States)

    2005-10-25T23:59:59.000Z

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

  6. Biological Imaging by Soft X-ray Diffraction Microscopy

    SciTech Connect (OSTI)

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

    2005-01-01T23:59:59.000Z

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

  7. 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.

  8. 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.

  9. Standoff detection of hidden objects using backscattered ultra-intense laser-produced x-rays

    SciTech Connect (OSTI)

    Kuwabara, H. [IHI Corporation, 1, Shin-Nakahara-cho, Isogo-ku, Yokohama 235-8501 (Japan)] [IHI Corporation, 1, Shin-Nakahara-cho, Isogo-ku, Yokohama 235-8501 (Japan); Mori, Y.; Kitagawa, Y. [The Graduate School for the Creation of New Photonics Industries, 1955-1 Kurematsucho, Nishiku, Hamamatsu, Shizuoka 431-1202 (Japan)] [The Graduate School for the Creation of New Photonics Industries, 1955-1 Kurematsucho, Nishiku, Hamamatsu, Shizuoka 431-1202 (Japan)

    2013-08-28T23:59:59.000Z

    Ultra-intense laser-produced sub-ps X-ray pulses can detect backscattered signals from objects hidden in aluminium containers. Coincident measurements using primary X-rays enable differentiation among acrylic, copper, and lead blocks inside the container. Backscattering reveals the shapes of the objects, while their material composition can be identified from the modification methods of the energy spectra of backscattered X-ray beams. This achievement is an important step toward more effective homeland security.

  10. 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.

  11. 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.

  12. A Soft X-Ray Lag Detected in Centaurus A

    E-Print Network [OSTI]

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

    2015-01-01T23:59:59.000Z

    We performed time lag analysis on the X-ray light curves of Centaurus A (Cen A) obtained by the Gas Slit Camera (GSC) aboard the Monitor of All-sky X-ray Image (MAXI) in three energy bands (2--4 keV, 4--10 keV, and 10--20 keV). We discovered a soft X-ray lag relative to higher energies (soft lag) on a time scale of days by employing the discrete correlation function (DCF) and the z-transformed discrete correlation function (ZDCF) method in a flare episode. A peak in the DCF and the ZDCF was observed at a soft lag of $\\sim 5$ days in 2--4 keV versus 4--10 keV and in 4--10 keV versus 10--20 keV, and $\\sim 10$ days in 2--4 keV versus 10--20 keV. We found it difficult to explain the observed X-ray variation with the one-zone synchrotron self-Compton (SSC) model, in which the soft lags reflect the different cooling times of the relativistic electrons in these three energy bands. Alternatively, if the X-ray variation was produced in a corona surrounding or along the inner part of the accretion disk, we can explain ...

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

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

    Turner, Joshua J.; Nelson, Johanna; Huang, Xiaojing; Steinbrener, Jan; Jacobsen, Chris

    2013-06-01T23:59:59.000Z

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

  14. 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.

  15. 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. ...

  16. 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.

  17. Systems and methods for monitoring a solid-liquid interface

    DOE Patents [OSTI]

    Stoddard, Nathan G; Lewis, Monte A.; Clark, Roger F

    2013-06-11T23:59:59.000Z

    Systems and methods are provided for monitoring a solid-liquid interface during a casting process. The systems and methods enable determination of the location of a solid-liquid interface during the casting process.

  18. Data fusion in neutron and X-ray computed tomography

    SciTech Connect (OSTI)

    Schrapp, Michael J. [Siemens AG, Corporate Technology, Otto-Hahn-Ring 6, 81739 Munich (Germany); Physik Department E21, Technische Universität München, James-Franck-Strasse 1, 85747 Garching (Germany); Goldammer, Matthias [Siemens AG, Corporate Technology, Otto-Hahn-Ring 6, 81739 Munich (Germany); Schulz, Michael [Physik Department E21, Technische Universität München, James-Franck-Strasse 1, 85747 Garching (Germany); Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München, Lichtenbergstrasse 1, 85747 Garching (Germany); Issani, Siraj; Bhamidipati, Suryanarayana [Siemens AG, Corporate Technology, Bangalore (India); Böni, Peter [Physik Department E21, Technische Universität München, James-Franck-Strasse 1, 85747 Garching (Germany)

    2014-10-28T23:59:59.000Z

    We present a fusion methodology between neutron and X-ray computed tomography (CT). On the one hand, the inspection by X-ray CT of a wide class of multimaterials in non-destructive testing applications suffers from limited information of object features. On the other hand, neutron imaging can provide complementary data in such a way that the combination of both data sets fully characterizes the object. In this contribution, a novel data fusion procedure, called Fusion Regularized Simultaneous Algebraic Reconstruction Technique, is developed where the X-ray reconstruction is modified to fulfill the available data from the imaging with neutrons. The experiments, which were obtained from an aluminum profile containing a steel screw, and attached carbon fiber plates demonstrate that the image quality in CT can be significantly improved when the proposed fusion method is used.

  19. X-ray radiography with highly charged ions

    DOE Patents [OSTI]

    Marrs, Roscoe E. (Livermore, CA)

    2000-01-01T23:59:59.000Z

    An extremely small (1-250 micron FWHM) beam of slow highly charged ions deexciting on an x-ray production target generates x-ray monochromatic radiation that is passed through a specimen and detected for imaging. The resolution of the x-ray radiograms is improved and such detection is achieved with relatively low dosages of radiation passing through the specimen. An apparatus containing an electron beam ion trap (and modifications thereof) equipped with a focusing column serves as a source of ions that generate radiation projected onto an image detector. Electronic and other detectors are able to detect an increased amount of radiation per pixel than achieved by previous methods and apparati.

  20. 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.

  1. 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.

  2. High-resolution X-ray spectroscopy of Theta Car

    E-Print Network [OSTI]

    Yael Naze; Gregor Rauw

    2008-08-25T23:59:59.000Z

    Context : The peculiar hot star Theta Car in the open cluster IC2602 is a blue straggler as well as a single-line binary of short period (2.2d). Aims : Its high-energy properties are not well known, though X-rays can provide useful constraints on the energetic processes at work in binaries as well as in peculiar, single objects. Methods : We present the analysis of a 50ks exposure taken with the XMM-Newton observatory. It provides medium as well as high-resolution spectroscopy. Results : Our high-resolution spectroscopy analysis reveals a very soft spectrum with multiple temperature components (1--6MK) and an X-ray flux slightly below the `canonical' value (log[L_X(0.1-10.)/L_{BOL}] ~ -7). The X-ray lines appear surprisingly narrow and unshifted, reminiscent of those of beta Cru and tau Sco. Their relative intensities confirm the anomalous abundances detected in the optical domain (C strongly depleted, N strongly enriched, O slightly depleted). In addition, the X-ray data favor a slight depletion in neon and iron, but they are less conclusive for the magnesium abundance (solar-like?). While no significant changes occur during the XMM-Newton observation, variability in the X-ray domain is detected on the long-term range. The formation radius of the X-ray emission is loosely constrained to <5 R_sol, which allows for a range of models (wind-shock, corona, magnetic confinement,...) though not all of them can be reconciled with the softness of the spectrum and the narrowness of the lines.

  3. Novel method for the prediction of an interface bonding species at alumina/metal interfaces

    SciTech Connect (OSTI)

    Yoshitake, Michiko, E-mail: yoshitake.michiko@nims.go.jp; Yagyu, Shinjiro [National Institute for Materials Science, 3-13, Sakura, Tsukuba 305-0003 (Japan); Chikyow, Toyohiro [National Institute for Materials Science, 1-1, Namiki, Tsukuba 305-0044 (Japan)

    2014-03-15T23:59:59.000Z

    Interface bonding between alumina and various metals is discussed from the viewpoint of chemical thermodynamics. A method to predict the interface bonding species at an alumina/metal interface under equilibrium conditions is proposed by using the concept of chemical equilibrium for interface termination. The originality of this method is in the way a simple estimation of the interface binding energy, which is generally applicable to most metals, is developed. The effectiveness of this method is confirmed by careful examination of the experimental results. Comparison of the predicted and experimentally observed interface terminations reveals that the proposed method agrees well with the reported results. The method uses only basic quantities of pure elements and the formation enthalpy of oxides. Therefore, it can be applied to most metals in the periodic table and is useful for screening materials in the quest to develop interfaces with particular functions.

  4. Materials Chemistry and Physics 100 (2006) 3840 X-ray irradiation induced degradation of cellulose nitrate

    E-Print Network [OSTI]

    Yu, K.N.

    Abstract Energy-dispersive X-ray fluorescence (EDXRF) spectrometry was previously proposed to measure energy-dispersive X-ray fluorescence (EDXRF) spectrometry. For that method, a reference silver nitrate-ray energy is high enough to avoid total a

  5. 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

  6. 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.

  7. Modification of the TASMIP x-ray spectral model for the simulation of microfocus x-ray sources

    SciTech Connect (OSTI)

    Sisniega, A.; Vaquero, J. J., E-mail: juanjose.vaquero@uc3m.es [Departamento de Bioingeniería e Ingeniería Aeroespacial, Universidad Carlos III de Madrid, Madrid ES28911 (Spain); Instituto de Investigación Sanitaria Gregorio Marañón, Madrid ES28007 (Spain); Desco, M. [Departamento de Bioingeniería e Ingeniería Aeroespacial, Universidad Carlos III de Madrid, Madrid ES28911 (Spain) [Departamento de Bioingeniería e Ingeniería Aeroespacial, Universidad Carlos III de Madrid, Madrid ES28911 (Spain); Instituto de Investigación Sanitaria Gregorio Marañón, Madrid ES28007 (Spain); Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid ES28029 (Spain)

    2014-01-15T23:59:59.000Z

    Purpose: The availability of accurate and simple models for the estimation of x-ray spectra is of great importance for system simulation, optimization, or inclusion of photon energy information into data processing. There is a variety of publicly available tools for estimation of x-ray spectra in radiology and mammography. However, most of these models cannot be used directly for modeling microfocus x-ray sources due to differences in inherent filtration, energy range and/or anode material. For this reason the authors propose in this work a new model for the simulation of microfocus spectra based on existing models for mammography and radiology, modified to compensate for the effects of inherent filtration and energy range. Methods: The authors used the radiology and mammography versions of an existing empirical model [tungsten anode spectral model interpolating polynomials (TASMIP)] as the basis of the microfocus model. First, the authors estimated the inherent filtration included in the radiology model by comparing the shape of the spectra with spectra from the mammography model. Afterwards, the authors built a unified spectra dataset by combining both models and, finally, they estimated the parameters of the new version of TASMIP for microfocus sources by calibrating against experimental exposure data from a microfocus x-ray source. The model was validated by comparing estimated and experimental exposure and attenuation data for different attenuating materials and x-ray beam peak energy values, using two different x-ray tubes. Results: Inherent filtration for the radiology spectra from TASMIP was found to be equivalent to 1.68 mm Al, as compared to spectra obtained from the mammography model. To match the experimentally measured exposure data the combined dataset required to apply a negative filtration of about 0.21 mm Al and an anode roughness of 0.003 mm W. The validation of the model against real acquired data showed errors in exposure and attenuation in line with those reported for other models for radiology or mammography. Conclusions: A new version of the TASMIP model for the estimation of x-ray spectra in microfocus x-ray sources has been developed and validated experimentally. Similarly to other versions of TASMIP, the estimation of spectra is very simple, involving only the evaluation of polynomial expressions.

  8. High power x-ray welding of metal-matrix composites

    DOE Patents [OSTI]

    Rosenberg, Richard A. (Naperville, IL); Goeppner, George A. (Orland Park, IL); Noonan, John R. (Naperville, IL); Farrell, William J. (Flossmoor, IL); Ma, Qing (Westmont, IL)

    1999-01-01T23:59:59.000Z

    A method for joining metal-matrix composites (MMCs) by using high power x-rays as a volumetric heat source is provided. The method involves directing an x-ray to the weld line between two adjacent MMCs materials to create an irradiated region or melt zone. The x-rays have a power density greater than about 10.sup.4 watts/cm.sup.2 and provide the volumetric heat required to join the MMC materials. Importantly, the reinforcing material of the metal-matrix composites remains uniformly distributed in the melt zone, and the strength of the MMCs are not diminished. In an alternate embodiment, high power x-rays are used to provide the volumetric heat required to weld metal elements, including metal elements comprised of metal alloys. In an alternate embodiment, high power x-rays are used to provide the volumetric heat required to weld metal elements, including metal elements comprised of metal alloys.

  9. 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...

  10. 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...

  11. 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...

  12. 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...

  13. 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) ...

  14. 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.

  15. 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

  16. 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.

  17. 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...

  18. 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.

  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. 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.

  1. A new endstation at the Swiss Light Source for ultraviolet photoelectron spectroscopy, X-ray photoelectron spectroscopy, and X-ray absorption spectroscopy measurements of liquid solutions

    SciTech Connect (OSTI)

    Brown, Matthew A.; Redondo, Amaia Beloqui; Duyckaerts, Nicolas; Mächler, Jean-Pierre [Institute for Chemical and Bioengineering, ETH Zürich, CH-8093 Zürich (Switzerland)] [Institute for Chemical and Bioengineering, ETH Zürich, CH-8093 Zürich (Switzerland); Jordan, Inga; Wörner, Hans Jakob [Laboratory of Physical Chemistry, ETH Zürich, CH-8093 Zürich (Switzerland)] [Laboratory of Physical Chemistry, ETH Zürich, CH-8093 Zürich (Switzerland); Lee, Ming-Tao; Ammann, Markus; Nolting, Frithjof; Kleibert, Armin; Huthwelker, Thomas; Birrer, Mario; Honegger, Juri; Wetter, Reto [Paul Scherrer Institute, CH-5232 Villigen PSI (Switzerland)] [Paul Scherrer Institute, CH-5232 Villigen PSI (Switzerland); Bokhoven, Jeroen A. van [Institute for Chemical and Bioengineering, ETH Zürich, CH-8093 Zürich (Switzerland) [Institute for Chemical and Bioengineering, ETH Zürich, CH-8093 Zürich (Switzerland); Paul Scherrer Institute, CH-5232 Villigen PSI (Switzerland)

    2013-07-15T23:59:59.000Z

    A new liquid microjet endstation designed for ultraviolet (UPS) and X-ray (XPS) photoelectron, and partial electron yield X-ray absorption (XAS) spectroscopies at the Swiss Light Source is presented. The new endstation, which is based on a Scienta HiPP-2 R4000 electron spectrometer, is the first liquid microjet endstation capable of operating in vacuum and in ambient pressures up to the equilibrium vapor pressure of liquid water at room temperature. In addition, the Scienta HiPP-2 R4000 energy analyzer of this new endstation allows for XPS measurements up to 7000 eV electron kinetic energy that will enable electronic structure measurements of bulk solutions and buried interfaces from liquid microjet samples. The endstation is designed to operate at the soft X-ray SIM beamline and at the tender X-ray Phoenix beamline. The endstation can also be operated using a Scienta 5 K ultraviolet helium lamp for dedicated UPS measurements at the vapor-liquid interface using either He I or He II ? lines. The design concept, first results from UPS, soft X-ray XPS, and partial electron yield XAS measurements, and an outlook to the potential of this endstation are presented.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. Characterizing Low-Permeable Granitic Rock From Micrometer to Centimeter Scale: X-ray Micro-computed Tomography, Confocal Laser Scanning Microscopy and {sup 14}C-PMMA Method

    SciTech Connect (OSTI)

    Laehdemaeki, T.; Kelokaski, M.; Siitari-Kauppi, M. [Laboratory of Radiochemistry, University of Helsinki, P.O.Box 55, University of Helsinki, FIN- 00014 (Finland); Voutilainen, M.; Myllys, M.; Turpeinen, T.; Timonen, J. [Department of Physics, University of Jyvaeskylae, P.O.Box 35, Jyvaeskylae, FIN-40351 (Finland); Mateos, F.; Montoto, M. [Department of Geology, University of Oviedo, Oviedo, 33005 (Spain)

    2007-07-01T23:59:59.000Z

    First results of combining X-ray micro-computed tomography ({mu}CT), confocal laser-scanning microscopy (CLSM) and {sup 14}C-poly-methyl-methacrylate ({sup 14}C-PMMA) impregnation techniques in the study of granitic rock samples are reported. Combining results of {mu}CT and CLSM with those of the {sup 14}C-PMMA technique, the mineral-specific porosity and morphology of the open pore space, as well as its connectivity, could be analyzed from a micrometer up to a decimeter scale. Three different types of granite were studied. In two cases part of the micro-fissure and pore apertures were found to be in a micrometer scale, but in one case all grain-boundary openings were below the detection limit. Micrometer-scale apertures could be analyzed by CLSM and {mu}CT. The benefit of {mu}CT is that it can also provide the heterogeneous distribution of minerals in 3D. The 2D porosity distributions in the mineral phases, consisting of nanometer-scale pores, could be measured by the {sup 14}C-PMMA method together with the micro-fissures. This method does not, however, give the exact pore apertures. The limitations and applicability of the methods are discussed. (authors)

  7. 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.

  8. 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.

  9. Standard test method for determination of bromine and chlorine in UF6 and uranyl nitrate by X-Ray fluorescence (XRF) spectroscopy

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2001-01-01T23:59:59.000Z

    1.1 This method covers the determination of bromine (Br) and chlorine (Cl) in uranium hexafluoride (UF6) and uranyl nitrate solution. The method as written covers the determination of bromine in UF6 over the concentration range of 0.2 to 8 ?g/g, uranium basis. The chlorine in UF6 can be determined over the range of 4 to 160 ?g/g, uranium basis. Higher concentrations may be covered by appropriate dilutions. The detection limit for Br is 0.2 ?g/g uranium basis and for Cl is 4 ?g/g uranium basis. 1.2 This standard may involve hazardous materials, operations and equipment. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  10. 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.

  11. Deep x-ray lithography for micromechanics

    SciTech Connect (OSTI)

    Christenson, T.R. [Sandia National Labs., Albuquerque, NM (United States); Guckel, H. [Wisconsin Univ., Madison, WI (United States). Dept. of Electrical and Computer Engineering

    1995-08-01T23:59:59.000Z

    Extensions of the German LIGA process have brought about fabrication capability suitable for cost effective production of precision engineered components. The process attributes allow fabrication of mechanical components which are not capable of being made via conventional subtractive machining methods. Two process improvements have been responsible for this extended capability which involve the areas of thick photoresist application and planarization via precision lapping. Application of low-stress x-ray photoresist has been achieved using room temperature solvent bonding of a preformed photoresist sheet. Precision diamond lapping and polishing has provided a flexible process for the planarization of a wide variety of electroplated metals in the presence of photoresist. Exposure results from the 2.5 GeV National Synchrotron Light Source storage ring at Brookhaven National Laboratory have shown that structural heights of several millimeter and above are possible. The process capabilities are also well suited for microactuator fabrication. Linear and rotational magnetic microactuators have been constructed which use coil winding technology with LIGA fabricated coil forms. Actuator output forces of 1 milliNewton have been obtained with power dissipation on the order of milliWatts. A rotational microdynamometer system which is capable of measuring torque-speed data is also discussed.

  12. Segmentation of x-ray images using Probabilistic Relaxation Labeling

    SciTech Connect (OSTI)

    Thai, T.Q.

    1991-01-01T23:59:59.000Z

    Segmentation is a process of separating objects of interest from their background or from other objects in an image. Without a suitable segmentation scheme, it is very difficult to detect contraband in X-rays images. In this paper, a Probabilistic Relaxation Labeling (PRL) segmentation scheme is presented and compared with other segmentation methods. PRL segmentation is an interative algorithm that labels each pixel in an image by cooperative use of two information sources: the pixel probability and the degree of certainty of its probability supported by the neighboring pixels. The practical implementation and results of the PRL segmentation on X-ray baggage images are also discussed and compared with other segmentation methods. 13 refs., 12 figs.

  13. Phase Effects on Mesoscale Object X-ray Absorption Images

    SciTech Connect (OSTI)

    Martz, Jr., H E; Aufderheide, M B; Barty, A; Lehman, S K; Kozioziemski, B J; Schneberk, D J

    2004-09-24T23:59:59.000Z

    At Lawrence Livermore National Laboratory particular emphasis is being placed on the nondestructive characterization (NDC) of 'mesoscale' objects.[Martz and Albrecht 2003] We define mesoscale objects as objects that have mm extent with {micro}m features. Here we confine our discussions to x-ray imaging methods applicable to mesoscale object characterization. The goal is object recovery algorithms including phase to enable emerging high-spatial resolution x-ray imaging methods to ''see'' inside or image mesoscale-size materials and objects. To be successful our imaging characterization effort must be able to recover the object function to one micrometer or better spatial resolution over a few millimeters field-of-view with very high contrast.

  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. 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.

  16. 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.

  17. 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

  18. 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

  19. 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.

  20. 2D X-ray scanner and its uses in laboratory reservoir characterization measurements

    SciTech Connect (OSTI)

    Maloney, D.; Doggett, K.

    1997-08-01T23:59:59.000Z

    X-ray techniques are used in petroleum laboratories for a variety of reservoir characterization measurements. This paper describes the configuration of a 2D X-ray scanner and many of the ways in which it simplifies and improves accuracy`s of laboratory measurements. Linear X-ray scanners are most often used to provide descriptions of fluid saturations within core plugs during flow tests. We configured our linear scanner for both horizontal and vertical movement. Samples can be scanned horizontally, vertically, or according to horizontal and vertical grids. X-ray measurements are fast, allowing measurements of two- and three-phase fluid saturations during both steady- and unsteady-state flow processes. Rock samples can be scanned while they are subjected to stress, pore pressure, and temperature conditions simulating those of a petroleum reservoir. Many types of measurements are possible by selecting appropriate X-ray power settings, dopes, filters, and collimator configurations. The scanner has been used for a variety of applications besides fluid saturation measurements. It is useful for measuring porosity distributions in rocks, concentrations of X-ray dopes within flow streams during tracer tests, gap widths in fracture flow cells, fluid interface levels in PVT cells and fluid separators, and other features and phenomena.

  1. 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.

  2. 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.

  3. 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

  4. 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.

  5. 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...

  6. Design and modeling of a third generation slumping tool for X-ray telescope mirrors/

    E-Print Network [OSTI]

    Al Husseini, Abdul Mohsen Z. (Abdul Mohsen Zuheir)

    2011-01-01T23:59:59.000Z

    Glass sheets with high surface quality and angular resolution of 5 arcsec are in demand for the International X-Ray Observatory. Several glass flattening techniques are presented in this thesis, including a method of ...

  7. Thin optic surface analysis for high resolution X-ray telescopes

    E-Print Network [OSTI]

    Akilian, Mireille

    2004-01-01T23:59:59.000Z

    The art of glass developed throughout the years has covered artifacts ranging from crude ornaments to high precision optics used in flat panel displays, hard disk drives, and x-ray telescopes. Methods for manufacturing ...

  8. PROSPECTS FOR MEASURING NEUTRON-STAR MASSES AND RADII WITH X-RAY PULSE PROFILE MODELING

    E-Print Network [OSTI]

    Psaltis, Dimitrios

    Modeling the amplitudes and shapes of the X-ray pulsations observed from hot, rotating neutron stars provides a direct method for measuring neutron-star properties. This technique constitutes an important part of the science ...

  9. A proposal for a generation of two-color ultra-short x-ray pulses

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

    in this paper. II. Method The following conditions were assumed to be essential for a new proposal: a) photon energies for the first and the second x-ray pulses can be...

  10. 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.

  11. 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).

  12. 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.

  13. Quantitative determination of mineral composition by powder x-ray diffraction

    DOE Patents [OSTI]

    Pawloski, G.A.

    1984-08-10T23:59:59.000Z

    An external standard intensity ratio method is used for quantitatively determining mineralogic compositions of samples by x-ray diffraction. The method uses ratios of x-ray intensity peaks from a single run. Constants are previously determined for each mineral which is to be quantitatively measured. Ratios of the highest intensity peak of each mineral to be quantified in the sample and the highest intensity peak of a reference mineral contained in the sample are used to calculate sample composition.

  14. Efficient electronic structure calculation for molecular ionization dynamics at high x-ray intensity

    E-Print Network [OSTI]

    Hao, Yajiang; Hanasaki, Kota; Son, Sang-Kil; Santra, Robin

    2015-01-01T23:59:59.000Z

    We present the implementation of an electronic-structure approach dedicated to ionization dynamics of molecules interacting with x-ray free-electron laser (XFEL) pulses. In our scheme, molecular orbitals for molecular core-hole states are represented by linear combination of numerical atomic orbitals that are solutions of corresponding atomic core-hole states. We demonstrate that our scheme efficiently calculates all possible multiple-hole configurations of molecules formed during XFEL pulses. The present method is suitable to investigate x-ray multiphoton multiple ionization dynamics and accompanying nuclear dynamics, providing essential information on the chemical dynamics relevant for high-intensity x-ray imaging.

  15. Dynamics in shear flow studied by X-ray Photon Correlation Spectroscopy

    E-Print Network [OSTI]

    Sebastian Busch; Torben Haugaard Jensen; Yuriy Chushkin; Andrei Fluerasu

    2008-03-19T23:59:59.000Z

    X-ray photon correlation spectroscopy was used to measure the diffusive dynamics of colloidal particles in a shear flow. The results presented here show how the intensity autocorrelation functions measure both the diffusive dynamics of the particles and their flow-induced, convective motion. However, in the limit of low flow/shear rates, it is possible to obtain the diffusive component of the dynamics, which makes the method suitable for the study of the dynamical properties of a large class of complex soft-matter and biological fluids. An important benefit of this experimental strategy over more traditional X-ray methods is the minimization of X-ray induced beam damage. While the method can be applied also for photon correlation spectroscopy in the visible domain, our analysis shows that the experimental conditions under which it is possible to measure the diffusive dynamics are easier to achieve at higher q values (with X-rays).

  16. 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.

  17. 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.

  18. 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.

  19. 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).

  20. First results from the high-brightness x-ray spectroscopy beamline 9. 3.1 at ALS

    SciTech Connect (OSTI)

    Ng, W.; Jones, G.; Perera, R.C.C.

    1995-10-01T23:59:59.000Z

    Beamline 9.3.1 at the Advanced Light Source (ALS) is a windowless beamline, covering the 1-6 keV photon-energy range. This beamline is designed to achieve the goal of high brightness at the sample for use in the X-ray Atomic and Molecular Spectroscopy (XAMS) science, surface and interface science, biology, and x-ray optical development programs at ALS. X-ray absorption and time of flight photoemission measurements in 2 - 5 keV photon energy along with the flux, resolution, spot size and stability of the beamline will be discussed. Prospects for future XAMS measurements will also be presented.

  1. 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

  2. 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.

  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.; 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.

  4. Is the Calcite-Water Interface Understood? Direct Comparisons...

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

    Is the Calcite-Water Interface Understood? Direct Comparisons of Molecular Dynamics Simulations with Specular X-ray Reflectivity Is the Calcite-Water Interface Understood? Direct...

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. High-resolution x-ray diffraction microscopy of specifically labeled yeast cells

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

    Nelson, Johanna; Huang, Xiaojing; Steinbrener, Jan; Shapiro, David; Kirz, Janos; Marchesini, Stephano; Neiman, Aaron M.; Turner, Joshua J.; Jacobsen, Chris

    2010-04-20T23:59:59.000Z

    X-ray diffraction microscopy complements other x-ray microscopy methods by being free of lens-imposed radiation dose and resolution limits, and it allows for high-resolution imaging of biological specimens too thick to be viewed by electron microscopy. We report here the highest resolution (11-13 nm) x-ray diffraction micrograph of biological specimens, and a demonstration of molecular-specific gold labeling at different depths within cells via through-focus propagation of the reconstructed wavefield. The lectin concanavalin A conjugated to colloidal gold particles was used to label the ?-mannan sugar in the cell wall of the yeast Saccharomyces cerevisiae. Cells were plunge-frozen in liquid ethane andmore »freeze-dried, after which they were imaged whole using x-ray diffraction microscopy at 750 eV photon energy.« less

  13. High-resolution x-ray diffraction microscopy of specifically labeled yeast cells

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

    Nelson, Johanna [Stony Brook Univ., Stony Brook, NY (United States); Huang, Xiaojing [Stony Brook Univ., Stony Brook, NY (United States); Steinbrener, Jan [Stony Brook Univ., Stony Brook, NY (United States); Shapiro, David [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source; Kirz, Janos [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source; Marchesini, Stephano [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source; Neiman, Aaron M. [Northwestern Univ., Evanston, IL (United States); Turner, Joshua J. [Stony Brook Univ., Stony Brook, NY (United States); Jacobsen, Chris [Stony Brook Univ., Stony Brook, NY (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source; Argonne National Laboratory (ANL), Argonne, IL (United States). Advanced Photon Source

    2010-04-20T23:59:59.000Z

    X-ray diffraction microscopy complements other x-ray microscopy methods by being free of lens-imposed radiation dose and resolution limits, and it allows for high-resolution imaging of biological specimens too thick to be viewed by electron microscopy. We report here the highest resolution (11-13 nm) x-ray diffraction micrograph of biological specimens, and a demonstration of molecular-specific gold labeling at different depths within cells via through-focus propagation of the reconstructed wavefield. The lectin concanavalin A conjugated to colloidal gold particles was used to label the ?-mannan sugar in the cell wall of the yeast Saccharomyces cerevisiae. Cells were plunge-frozen in liquid ethane and freeze-dried, after which they were imaged whole using x-ray diffraction microscopy at 750 eV photon energy.

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

    SciTech Connect (OSTI)

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

    2011-01-12T23:59:59.000Z

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

  15. Fat to Muscle Ratio Measurements with Dual Energy X Ray Absorbtiometry

    E-Print Network [OSTI]

    Chen, A; Broadbent, C; Zhong, J; Dilmanian, A; Zafonte, F; Zhong, Z

    2014-01-01T23:59:59.000Z

    Accurate measurement of the fat-to-muscle ratio in animal model is important for obesity research. An efficient way to measure the fat to muscle ratio in animal model using dual-energy absorptiometry is presented in this paper. A radioactive source exciting x-ray fluorescence from a target material is used to provide the two x-ray energies needed. The x-rays, after transmitting through the sample, are measured with an energy-sensitive Ge detector. Phantoms and specimens were measured. The results showed that the method was sensitive to the fat to muscle ratios with good linearity. A standard deviation of a few percent in the fat to muscle ratio could be observed with the x-ray dose of 0.001 mGy.

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

    SciTech Connect (OSTI)

    Lu, L. [CAS Key Laboratory of Mechanical Behavior and Design of Materials, Department of Modern Mechanics, University of Science and Technology of China, Hefei, Anhui 230027 (China); The Peac Institute of Multiscale Sciences, Chengdu, Sichuan 610207 (China); Fan, D.; Luo, S. N., E-mail: sluo@pims.ac.cn [The Peac Institute of Multiscale Sciences, Chengdu, Sichuan 610207 (China); Bie, B. X. [The Peac Institute of Multiscale Sciences, Chengdu, Sichuan 610207 (China); School of Science, Wuhan University of Technology, Wuhan, Hubei 430070 (China); Ran, X. X.; Qi, M. L., E-mail: qiml@whut.edu.cn [School of Science, Wuhan University of Technology, Wuhan, Hubei 430070 (China); Parab, N.; Sun, J. Z.; Liao, H. J.; Hudspeth, M. C.; Claus, B. [School of Aeronautics and Astronautics, Purdue University, West Lafayette, Indiana 47907 (United States); Fezzaa, K.; Sun, T. [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Chen, W. [School of Aeronautics and Astronautics, Purdue University, West Lafayette, Indiana 47907 (United States); School of Material Science Engineering, Purdue University, West Lafayette, Indiana 47907 (United States); Gong, X. L., E-mail: gongxl@ustc.edu.cn [CAS Key Laboratory of Mechanical Behavior and Design of Materials, Department of Modern Mechanics, University of Science and Technology of China, Hefei, Anhui 230027 (China)

    2014-07-15T23:59:59.000Z

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

  17. Photosynthesis and structure of electroless Ni-P films by synchrotron x-ray irradiation

    SciTech Connect (OSTI)

    Hsu, P.-C.; Wang, C.-H.; Yang, T.-Y.; Hwu, Y.-K.; Lin, C.-S.; Chen, C.-H.; Chang, L.-W.; Seol, S.-K.; Je, J.-H.; Margaritondo, G. [Institute of Physics, Academia Sinica, NanKang, Taipei 115, Taiwan and Department of Materials Science and Engineering, National Taiwan University, Taipei 106, Taiwan (China); Institute of Physics, Academia Sinica, NanKang, Taipei 115, Taiwan (China); Institute of Physics, Academia Sinica, NanKang, Taipei 115, Taiwan (China); Department of Engineering and System Science, National Tsing Hua University, Hsinchu, 300, Taiwan (China) and Institute of Optoelectronic Sciences, National Taiwan Ocean University, Keelung 202, Taiwan (China); Department of Materials Science and Engineering, National Taiwan University, Taipei 106, Taiwan (China); Kinsus Interconnect Technology Co., Taoyuang 327, Taiwan (China); Department of Materials Science and Optoelectronic Engineering, National Sun Yat-Sen University, Kaoshung 804, Taiwan (China); X-ray Imaging Center, Pohang University of Science and Technology, Pohang 790-784 (Korea, Republic of) and Department of Materials Science and Engineering, Pohang University of Science and Technology, Pohang 790-784 (Korea); Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland)

    2007-05-15T23:59:59.000Z

    The authors describe an electroless deposition method for thin films, based on the irradiation by an x-ray beam emitted by a synchrotron source. Specifically, Ni-P films were deposited at room temperature. This synthesis is a unique combination of photochemical and electrochemical processes. The influence of the pH value on the formation and structural properties of the films was examined by various characterization tools including scanning electron microscopy, x-ray diffraction, and x-ray absorption spectroscopy. Real time monitoring of the deposition process by coherent x-ray microscopy reveals that the formation of hydrogen bubbles leads to a self-catalysis effect without a preexisting catalyst. The mechanisms underlying the deposition process are discussed in details.

  18. Fat to muscle ratio measurements with dual energy x-ray absorbtiometry

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

    Chen, A.; Zhong, Z.; Luo, J.; Wang, A.; Broadbent, C.; Zhong, J.; Dilmanian, F. A.; Zafonte, F.

    2015-07-01T23:59:59.000Z

    Accurate measurement of the fat-to-muscle ratio in animal model is important for obesity research. An efficient way to measure the fat to muscle ratio in animal model using dual-energy absorptiometry is presented in this paper. A radioactive source exciting x-ray fluorescence from a target material is used to provide the two x-ray energies needed. The x-rays, after transmitting through the sample, are measured with an energy-sensitive Ge detector. Phantoms and specimens were measured. The results showed that the method was sensitive to the fat to muscle ratios with good linearity. A standard deviation of a few percent in the fatmore »to muscle ratio could be observed with the x-ray dose of 0.001 mGy.« less

  19. 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...

  20. 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...

  1. 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....

  2. 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...

  3. 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...

  4. Portable total reflection x-ray fluorescence analysis in the identification of unknown laboratory hazards

    SciTech Connect (OSTI)

    Liu, Ying, E-mail: liu.ying.48r@st.kyoto-u.ac.jp; Imashuku, Susumu; Sasaki, Nobuharu; Ze, Long; Kawai, Jun [Department of Materials Science and Engineering, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto 606-8501 (Japan); Takano, Shotaro; Sohrin, Yoshiki [Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); Seki, Hiroko; Miyauchi, Hiroya [Kyoto Prefectural Technology Center for Small and Medium Enterprises, Chudojiminami machi, Shimogyo-ku, Kyoto 600-8813 (Japan)

    2014-05-15T23:59:59.000Z

    In this study, a portable total reflection x-ray fluorescence (TXRF) spectrometer was used to analyze unknown laboratory hazards that precipitated on exterior surfaces of cooling pipes and fume hood pipes in chemical laboratories. With the aim to examine the accuracy of TXRF analysis for the determination of elemental composition, analytical results were compared with those of wavelength-dispersive x-ray fluorescence spectrometry, scanning electron microscope and energy-dispersive x-ray spectrometry, energy-dispersive x-ray fluorescence spectrometry, inductively coupled plasma atomic emission spectrometry, x-ray diffraction spectrometry (XRD), and x-ray photoelectron spectroscopy (XPS). Detailed comparison of data confirmed that the TXRF method itself was not sufficient to determine all the elements (Z?>?11) contained in the samples. In addition, results suggest that XRD should be combined with XPS in order to accurately determine compound composition. This study demonstrates that at least two analytical methods should be used in order to analyze the composition of unknown real samples.

  5. 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...

  6. 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.

  7. A novel instrument for quantitative nanoanalytics involving complementary X-ray methodologies

    SciTech Connect (OSTI)

    Lubeck, J.; Beckhoff, B.; Fliegauf, R.; Holfelder, I.; Hoenicke, P.; Mueller, M.; Pollakowski, B.; Reinhardt, F.; Weser, J. [Physikalisch-Technische Bundesanstalt, Abbestr. 2-12, 10587 Berlin (Germany)

    2013-04-15T23:59:59.000Z

    A novel ultra-high vacuum instrument for X-ray reflectometry and spectrometry-related techniques for nanoanalytics by means of synchrotron radiation has been constructed and commissioned. This versatile instrument was developed by the Physikalisch-Technische Bundesanstalt, Germany's national metrology institute, and includes a 9-axis manipulator that allows for an independent alignment of the samples with respect to all degrees of freedom. In addition, a rotational and translational movement of several photodiodes as well as a translational movement of an aperture system in and out of the beam is provided. Thus, the new instrument enables various analytical techniques based on energy dispersive X-ray detectors such as reference-free X-ray fluorescence analysis (XRF), total-reflection XRF, grazing-incidence XRF in addition to optional X-ray reflectometry measurements or polarization-dependent X-ray absorption fine structure analyses. With this instrument samples having a size of up to 100 mm Multiplication-Sign 100 mm can be analyzed with respect to their mass deposition, elemental or spatial composition, or the species in order to probe surface contamination, layer composition and thickness, the depth profile of matrix elements or implants, the species of nanolayers, nanoparticles or buried interfaces as well as the molecular orientation of bonds. Selected applications of this advanced ultra-high vacuum instrument demonstrate both its flexibility and capability.

  8. 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.

  9. 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.

  10. 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

  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. 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.

  13. 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.

  14. Installation of soft X-ray array diagnostics and its application to tomography reconstruction using synthetic KSTAR X-ray images

    SciTech Connect (OSTI)

    Lee, Seung Hun; Jang, Juhyeok; Hong, Joohwan; Jang, Siwon; Choe, Wonho, E-mail: wchoe@kaist.ac.kr [Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Korea, Republic of); Impurity and Edge Research Center, Daejeon 305-701 (Korea, Republic of); Pacella, D.; Romano, A.; Gabellieri, L. [Associazione Euratom-ENEA sulla Fusione, C.R. Frascati 00044 (Italy); Kim, Junghee [National Fusion Research Institute, Daejeon 305-806 (Korea, Republic of); Major of Nuclear Fusion and Plasma Science Department, Korea University of Science and Technology, Daejeon 305-350 (Korea, Republic of)

    2014-11-15T23:59:59.000Z

    Four-array system of soft X-ray diagnostics was installed on KSTAR tokamak. Each array has 32 viewing chords of two photo-diode array detectors with spatial resolution of 2 cm. To estimate signals from the soft X-ray radiation power, typical n{sub e}, T{sub e}, and argon impurity line radiation profiles in KSTAR are chosen. The photo-diodes were absolutely calibrated as a function of the incident photon energy in 2–40 keV range with a portable X-ray tube. Two-dimensional T{sub e} image properties by multi-energy method were simulated and visualized with six combinations of beryllium filter sets within the dynamic range of signal ratio.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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

  3. X-ray reflectivity studies of the metal/solution interphase

    SciTech Connect (OSTI)

    You, H.; Nagy, Z.; Melendres, C.A.; Zurawski, D.J.; Chiarello, R.P.; Yonco, R.M.; Kim, H.K.; Maroni, V.A.

    1991-09-01T23:59:59.000Z

    We have designed an electrochemical cell that permits x-ray scattering studies in a transmission geometry under in-situ electrochemical control and have performed x-ray specular reflectivity studies of several metal/solution interphases as a function of electrochemical potential. For the copper/solution interphase, we found that the reflectivity changes upon oxidation and reduction, indicating a phase transition between copper and copper oxide at the interphase. We also found that the thickness of the pure copper and the roughness of the interfaces exhibited electrochemical irreversibility that is consistent with the potentials for the oxidation waves in the anodic sweep and the reduction waves in the cathodic sweep of the voltammogram. A standard Fresnel expression for the x-ray specular reflectivity was applied in the data analysis, and a smoothly varying Lorentzian interface profile was used for the individual rough interfaces. Furthermore, an incoherent average was used to include the effect of correlated roughness between a pair of interfaces. Preliminary results are also presented for the silver/solution and platinum/solution interphases. 14 refs., 9 figs., 2 tabs.

  4. 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...

  5. 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.

  6. 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.

  7. 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

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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

  13. Feasibility of x ray fluorescence for spent fuel safeguards

    SciTech Connect (OSTI)

    Freeman, Corey Ross [Los Alamos National Laboratory; Mozin, Vladimir [Los Alamos National Laboratory; Tobin, Stephen J [Los Alamos National Laboratory; Fensin, Michael L [Los Alamos National Laboratory; White, Julia M [Los Alamos National Laboratory; Croft, Stephen [Los Alamos National Laboratory; Stafford, Alissa [TAMU; Charlton, William [TAMU

    2010-01-01T23:59:59.000Z

    Quantifying the Pu content in spent nuclear fuel is necessary for many reasons, in particular to verify that diversion or other illicit activities have not occurred. Therefore, safeguarding the world's nuclear fuel is paramount to responsible nuclear regulation and public acceptance, but achieving this goal presents many difficulties from both a technical and economic perspective. The Next Generation Safeguards Initiative (NGSI) of NA-24 is funding a large collaborative effort between multiple laboratories and universities to improve spent nuclear fuel safeguards methods and equipment. This effort involves the current work of modeling several different nondestructive assay (NDA) techniques. Several are being researched, because no single NDA technique, in isolation, has the potential to properly characterize fuel assemblies and offer a robust safeguards measure. The insights gained from this research, will be used to down-select from the original set a few of the most promising techniques that complement each other. The goal is to integrate the selected instruments to create an accurate measurement system for fuel verification that is also robust enough to detect diversions. These instruments will be fabricated and tested under realistic conditions. This work examines one of the NDA techniques; the feasibility of using x ray emission peaks from Pu and U to gather information about their relative quantities in the spent fuel. X Ray Fluorescence (XRF), is unique compared to the investigated techniques in that it is the only one able to give the elemental ratio of Pu to U, allowing the possibility of a Pu gram quantity for the assembly to be calculated. XRF also presents many challenges, mainly its low penetration, since the low energy x rays of interest are effectively shielded by the first few millimeters of a fuel pin. This paper will explore the results of Monte Carlo N-Particle eXtended (MCNPX) transport code calculations of spent fuel x ray peaks. The MCNPX simulations will be benchmarked against measurements taken at Oak Ridge. Analysis of the feasibility of XRFs role in spent nuclear fuel safeguards efforts, particularly in the context of the overall NGSI effort will be discussed.

  14. Constraints on the Bulk Lorentz Factors of GRB X-Ray Flares

    E-Print Network [OSTI]

    Yi, Shuang-Xi; Wang, Fa-Yin; Dai, Zi-Gao

    2015-01-01T23:59:59.000Z

    X-ray flares were discovered in the afterglow phase of gamma-ray bursts (GRBs) by the {\\em Swift} satellite a decade ago and known as a canonical component in GRB X-ray afterglows. In this paper, we constrain the Lorentz factors of GRB X-ray flares using two different methods. For the first method, we estimate the lower limit on the bulk Lorentz factor with the flare duration and jet break time. In the second method, the upper limit on the Lorentz factor is derived by assuming that the X-ray flare jet has undergone saturated acceleration. We also re-estimate the initial Lorentz factor with GRB afterglow onsets, and find the coefficient of the theoretical Lorentz factor is 1.67 rather than the commonly used 2 for interstellar medium (ISM) and 1.44 for the wind case. We find that the correlation between the limited Lorentz factor and the isotropic radiation energy of X-ray flares in the ISM case is more consistent with that of prompt emission than the wind case in a statistical sense. For a comparison, the lowe...

  15. 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,...

  16. In situ x-ray photoelectron spectroscopy for electrochemical reactions in ordinary solvents

    SciTech Connect (OSTI)

    Masuda, Takuya [Global Research Center for Environment and Energy Based on Nanomaterials Science (GREEN), National Institute for Materials Science (NIMS), Tsukuba 305-0044 (Japan) [Global Research Center for Environment and Energy Based on Nanomaterials Science (GREEN), National Institute for Materials Science (NIMS), Tsukuba 305-0044 (Japan); PRESTO, Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi, Saitama 333-0012 (Japan); Yoshikawa, Hideki; Kobata, Masaaki; Kobayashi, Keisuke [Synchrotron X-ray Station at SPring-8, National Institute for Materials Science (NIMS), Sayo, Hyogo 679-5148 (Japan)] [Synchrotron X-ray Station at SPring-8, National Institute for Materials Science (NIMS), Sayo, Hyogo 679-5148 (Japan); Noguchi, Hidenori [Global Research Center for Environment and Energy Based on Nanomaterials Science (GREEN), National Institute for Materials Science (NIMS), Tsukuba 305-0044 (Japan) [Global Research Center for Environment and Energy Based on Nanomaterials Science (GREEN), National Institute for Materials Science (NIMS), Tsukuba 305-0044 (Japan); PRESTO, Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi, Saitama 333-0012 (Japan); Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo, Hokkaido 060-0810 (Japan); International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044 (Japan); Kawasaki, Tadahiro [Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8603 (Japan)] [Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8603 (Japan); Uosaki, Kohei [Global Research Center for Environment and Energy Based on Nanomaterials Science (GREEN), National Institute for Materials Science (NIMS), Tsukuba 305-0044 (Japan) [Global Research Center for Environment and Energy Based on Nanomaterials Science (GREEN), National Institute for Materials Science (NIMS), Tsukuba 305-0044 (Japan); Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo, Hokkaido 060-0810 (Japan); International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044 (Japan)

    2013-09-09T23:59:59.000Z

    In situ electrochemical X-ray photoelectron spectroscopy (XPS) apparatus, which allows XPS at solid/liquid interfaces under potential control, was constructed utilizing a microcell with an ultra-thin Si membrane, which separates vacuum and a solution. Hard X-rays from a synchrotron source penetrate into the Si membrane surface exposed to the solution. Electrons emitted at the Si/solution interface can pass through the membrane and be analyzed by an analyzer placed in vacuum. Its operation was demonstrated for potential-induced Si oxide growth in water. Effect of potential and time on the thickness of Si and Si oxide layers was quantitatively determined at sub-nanometer resolution.

  17. Electrochemical flowcell for in-situ investigations by soft x-ray absorption and emission spectroscopy

    SciTech Connect (OSTI)

    Schwanke, C.; Lange, K. M., E-mail: Kathrin.lange@helmholtz-berlin.de [Helmholtz-Zentrum Berlin für Materialien und Energie, Institute of Solar Fuels, Albert-Einstein-Straße 15, 12489 Berlin (Germany); Golnak, R.; Xiao, J. [Helmholtz-Zentrum Berlin für Materialien und Energie, Institute of Methods for Material Development, Albert-Einstein-Straße 15, 12489 Berlin (Germany)

    2014-10-15T23:59:59.000Z

    A new liquid flow-cell designed for electronic structure investigations at the liquid-solid interface by soft X-ray absorption and emission spectroscopy is presented. A thin membrane serves simultaneously as a substrate for the working electrode and solid state samples as well as for separating the liquid from the surrounding vacuum conditions. In combination with counter and reference electrodes this approach allows in-situ studies of electrochemical deposition processes and catalytic reactions at the liquid-solid interface in combination with potentiostatic measurements. As model system in-situ monitoring of the deposition process of Co metal from a 10 mM CoCl{sub 2} aqueous solution by X-ray absorption and emission spectroscopy is presented.

  18. 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.

  19. Electrode/electrolyte interface. A status report

    SciTech Connect (OSTI)

    Bard, A.J. (Univ. of Texas, Austin (United States)); Abruna, H.D. (Cornell Univ., Ithaca, NY (United States)); Chidsey, C.E. (Stanford Univ., CA (United States)); Faulkner, L.R. (Univ. of Illinois, Urbana-Champaign (United States)); Feldberg, S.W. (Brookhaven National Lab., Upton, NY (United States)); Itaya, Kingo (Tohoku Univ., Sendai (Japan)); Majda, M. (Univ. of California, Berkeley (United States)); Melroy, O. (IBM Almaden Research Center, San Jose, CA (United States)); Murray, R.W. (Univ. of North Carolina, Chapel Hill (United States)); Porter, M.D. (Iowa State Univ., Ames (United States)); Soriaga, M.P. (Texas A M Univ., College Station (United States)); White, H.S. (Univ. of Utah, Salt Lake City (United States))

    1993-07-15T23:59:59.000Z

    This is a report of a workshop on the [open quotes]state of the art[close quotes] and potential future directions in the study of the electrode/electrolyte interface. Recent advances in experimental capabilities of characterizing the structure of the interface, e.g., through the use of such techniques as scanning tunneling microscopy and X-ray methods, are described. New approaches to studies of interfacial dynamics and materials aspects of the electrode/electrolyte interface are also discussed. 346 refs., 17 figs.

  20. Crushing of interstellar gas clouds in supernova remnants II. X-ray emission

    E-Print Network [OSTI]

    S. Orlando; F. Bocchino; G. Peres; F. Reale; T. Plewa; R. Rosner

    2006-07-12T23:59:59.000Z

    AIMS. We study and discuss the time-dependent X-ray emission predicted by hydrodynamic modeling of the interaction of a SNR shock wave with an interstellar gas cloud. The scope includes: 1) to study the correspondence between modeled and X-ray emitting structures, 2) to explore two different physical regimes in which either thermal conduction or radiative cooling plays a dominant role, and 3) to investigate the effects of the physical processes at work on the emission of the shocked cloud in the two different regimes. METHODS. We use a detailed hydrodynamic model, including thermal conduction and radiation, and explore two cases characterized by different Mach numbers of the primary shock: M = 30 in which the cloud dynamics is dominated by radiative cooling and M = 50 dominated by thermal conduction. From the simulations, we synthesize the expected X-ray emission, using available spectral codes. RESULTS. The morphology of the X-ray emitting structures is significantly different from that of the flow structures originating from the shock-cloud interaction. The hydrodynamic instabilities are never clearly visible in the X-ray band. Shocked clouds are preferentially visible during the early phases of their evolution. Thermal conduction and radiative cooling lead to two different phases of the shocked cloud: a cold cooling dominated core emitting at low energies and a hot thermally conducting corona emitting in the X-ray band. The thermal conduction makes the X-ray image of the cloud smaller, more diffuse, and shorter-lived than that observed when thermal conduction is neglected.

  1. 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.

  2. Dimensionality and noise in energy selective x-ray imaging

    SciTech Connect (OSTI)

    Alvarez, Robert E. [Aprend Technology, Mountain View, California 94043 (United States)] [Aprend Technology, Mountain View, California 94043 (United States)

    2013-11-15T23:59:59.000Z

    Purpose: To develop and test a method to quantify the effect of dimensionality on the noise in energy selective x-ray imaging.Methods: The Cramèr-Rao lower bound (CRLB), a universal lower limit of the covariance of any unbiased estimator, is used to quantify the noise. It is shown that increasing dimensionality always increases, or at best leaves the same, the variance. An analytic formula for the increase in variance in an energy selective x-ray system is derived. The formula is used to gain insight into the dependence of the increase in variance on the properties of the additional basis functions, the measurement noise covariance, and the source spectrum. The formula is also used with computer simulations to quantify the dependence of the additional variance on these factors. Simulated images of an object with three materials are used to demonstrate the trade-off of increased information with dimensionality and noise. The images are computed from energy selective data with a maximum likelihood estimator.Results: The increase in variance depends most importantly on the dimension and on the properties of the additional basis functions. With the attenuation coefficients of cortical bone, soft tissue, and adipose tissue as the basis functions, the increase in variance of the bone component from two to three dimensions is 1.4 × 10{sup 3}. With the soft tissue component, it is 2.7 × 10{sup 4}. If the attenuation coefficient of a high atomic number contrast agent is used as the third basis function, there is only a slight increase in the variance from two to three basis functions, 1.03 and 7.4 for the bone and soft tissue components, respectively. The changes in spectrum shape with beam hardening also have a substantial effect. They increase the variance by a factor of approximately 200 for the bone component and 220 for the soft tissue component as the soft tissue object thickness increases from 1 to 30 cm. Decreasing the energy resolution of the detectors increases the variance of the bone component markedly with three dimension processing, approximately a factor of 25 as the resolution decreases from 100 to 3 bins. The increase with two dimension processing for adipose tissue is a factor of two and with the contrast agent as the third material for two or three dimensions is also a factor of two for both components. The simulated images show that a maximum likelihood estimator can be used to process energy selective x-ray data to produce images with noise close to the CRLB.Conclusions: The method presented can be used to compute the effects of the object attenuation coefficients and the x-ray system properties on the relationship of dimensionality and noise in energy selective x-ray imaging systems.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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...

  12. Unexpected Angular Dependence of X-Ray Magnetic Linear Dichroism

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

    axes must be taken into account for accurate interpretation of XMLD data. Magnetism and X Rays The ancient Greeks and also the Chinese knew about strange and rare...

  13. Generation of Coherent X-Ray Radiation Through Modulation Compression

    E-Print Network [OSTI]

    Qiang, Ji

    2011-01-01T23:59:59.000Z

    ultra-short coherent X-ray radiation by controlling the fraction of the beam that can be properly unchirped using a few-cycle laser

  14. The Daguerreotype and the X-ray: A Deep Look

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

    - likely will play a crucial role in future scientific breakthroughs. Last week, hers was the first daguerreotype to undergo powerful x-ray analysis in a collaboration...

  15. Spectral Formation in X-Ray Pulsars: Bulk Comptonization in the Accretion Shock

    E-Print Network [OSTI]

    Peter A. Becker; Michael T. Wolff

    2005-05-06T23:59:59.000Z

    Accretion-powered X-ray pulsars are among the most luminous X-ray sources in the Galaxy. However, despite decades of theoretical and observational work since their discovery, no satisfactory model for the formation of the observed X-ray spectra has emerged. In particular, the previously available theories are unable to reproduce the power-law variation observed at high energies in many sources. In this paper, we present the first self-consistent calculation of the spectrum emerging from a pulsar accretion column that includes an explicit treatment of the energization occurring in the shock. Using a rigorous eigenfunction expansion method based on the exact dynamical solution for the velocity profile in the column, we obtain a closed-form expression for the Green's function describing the upscattering of radiation injected into the column from a monochromatic source located at the top of the thermal mound, near the base of the flow. The Green's function is convolved with a Planck distribution to calculate the radiation spectrum resulting from the reprocessing of blackbody photons emitted by the thermal mound. We demonstrate that the energization of the photons in the shock naturally produces an X-ray spectrum with a power-law shape at high energies and a blackbody shape at low energies, in agreement with many observations of accreting X-ray pulsars.

  16. 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.

  17. X-ray Spectroscopy for Quality Control of Chemotherapy Drugs

    SciTech Connect (OSTI)

    Greaves, E. D.; Barros, H.; Bermudez, J.; Sajo-Bohus, L. [Universidad Simon Bolivar, Apartado 89000, Caracas 1080A (Venezuela); Angeli-Greaves, M. [Universidad Central de Venezuela, Apartado 90373 Caracas 1083A (Venezuela)

    2007-10-26T23:59:59.000Z

    We develop a method, employing Compton peak standardization and the use of matrix-matched spiked samples with Total Reflection X-ray Fluorescence (TXRF), for the determination of platinum plasma concentrations of patients undergoing chemotherapy with Pt-bearing drugs. Direct blood plasma analysis attains Pt detection limits of 70 ng/ml. Measurement results of prescribed drug doses are compared to achieved blood Pt concentrations indicating a lack of expected correlations. Direct analysis of Pt-containing infused drugs from a variety of suppliers indicates cases of abnormal concentrations which raises quality control issues. We demonstrate the potential usefulness of the method for pharmacokinetic studies or for routine optimization and quality control of Pt chemotherapy treatments.

  18. Gas cell for in situ soft X-ray transmission-absorption spectroscopy of materials

    SciTech Connect (OSTI)

    Drisdell, W. S.; Kortright, J. B. [Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

    2014-07-15T23:59:59.000Z

    A simple gas cell design, constructed primarily from commercially available components, enables in situ soft X-ray transmission-absorption spectroscopy of materials in contact with gas at ambient temperature. The cell has a minimum X-ray path length of 1 mm and can hold gas pressures up to ?300 Torr, and could support higher pressures with simple modifications. The design enables cycling between vacuum and gas environments without interrupting the X-ray beam, and can be fully sealed to allow for measurements of air-sensitive samples. The cell can attach to the downstream port of any appropriate synchrotron beamline, and offers a robust and versatile method for in situ measurements of certain materials. The construction and operation of the cell are discussed, as well as sample preparation and proper spectral analysis, illustrated by examples of spectral measurements. Potential areas for improvement and modification for specialized applications are also mentioned.

  19. Femtosecond X-ray Diffraction From Two-Dimensional Protein Crystals

    SciTech Connect (OSTI)

    Frank, Matthias; Carlson, David B.; Hunter, Mark; Williams, Garth J.; Messerschmidt, Marc; Zatsepin, Nadia A.; Barty, Anton; Benner, Henry; Chu, Kaiqin; Graf, Alexander; Hau-Riege, Stefan; Kirian, Rick; Padeste, Celestino; Pardini, Tommaso; Pedrini, Bill; Segelke, Brent; Seibert, M. M.; Spence , John C.; Tsai, Ching-Ju; Lane, Steve M.; Li, Xiao-Dan; Schertler, Gebhard; Boutet, Sebastien; Coleman, Matthew A.; Evans, James E.

    2014-02-28T23:59:59.000Z

    Here we present femtosecond x-ray diffraction patterns from two-dimensional (2-D) protein crystals using an x-ray free electron laser (XFEL). To date it has not been possible to acquire x-ray diffraction from individual 2-D protein crystals due to radiation damage. However, the intense and ultrafast pulses generated by an XFEL permits a new method of collecting diffraction data before the sample is destroyed. Utilizing a diffract-before-destroy methodology at the Linac Coherent Light Source, we observed Bragg diffraction to better than 8.5 Å resolution for two different 2-D protein crystal samples that were maintained at room temperature. These proof-of-principle results show promise for structural analysis of both soluble and membrane proteins arranged as 2-D crystals without requiring cryogenic conditions or the formation of three-dimensional crystals.

  20. Deconvolving the temporal response of photoelectric x-ray detectors for the diagnosis of pulsed radiations

    SciTech Connect (OSTI)

    Zou, Shiyang; Song, Peng; Pei, Wenbing [Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China)] [Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China); Guo, Liang [Research Center of Laser Fusion, China Academy of Engineering Physics, P.O. Box 919-986, Mianyang 621900 (China)] [Research Center of Laser Fusion, China Academy of Engineering Physics, P.O. Box 919-986, Mianyang 621900 (China)

    2013-09-15T23:59:59.000Z

    Based on the conjugate gradient method, a simple algorithm is presented for deconvolving the temporal response of photoelectric x-ray detectors (XRDs) to reconstruct the resolved time-dependent x-ray fluxes. With this algorithm, we have studied the impact of temporal response of XRD on the radiation diagnosis of hohlraum heated by a short intense laser pulse. It is found that the limiting temporal response of XRD not only postpones the rising edge and peak position of x-ray pulses but also smoothes the possible fluctuations of radiation fluxes. Without a proper consideration of the temporal response of XRD, the measured radiation flux can be largely misinterpreted for radiation pulses of a hohlraum heated by short or shaped laser pulses.

  1. The puzzling temporally variable optical and X-ray afterglow of GRB 101024A

    E-Print Network [OSTI]

    Gendre, B; Laas-Bourez\\inst, M; Coward, D M; Klotz, A; Cutini, S; Boer, M; Stockdale, C

    2011-01-01T23:59:59.000Z

    Aim: To present the optical observations of the afterglow of GRB 101024A and to try to reconcile these observations with the X-ray afterglow data of GRB 101024A using current afterglow models Method: We employ early optical observations using the Zadko Telescope combined with X-ray data and compare with the reverse shock/forward shock model. Results: The early optical light curve reveals a very unusual steep decay index of alpha~5. This is followed by a flattening and possibly a plateau phase coincident with a similar feature in the X-ray. We discuss these observations in the framework of the standard reverse shock/forward shock model and energy injection.We note that the plateau phase might also be the signature of the formation of a new magnetar.

  2. Response Time Measurements of the NIF DANTE XRD-31 X-Ray Diodes (Pre-print)

    SciTech Connect (OSTI)

    Don Pellinen and Michael Griffin

    2009-01-23T23:59:59.000Z

    The XRD-31 is a fast, windowless X-ray vacuum photodiode developed by EG&G. It is currently the primary fast X-ray detector used to diagnose the X-rays on NIF and OMEGA on the multichannel DANTE spectrometer. The XRD-31 has a dynamic range of less than 1e-12 amps to more than 10 amps. A technique is described to measure the impulse response of the diodes to a 150 fs pulse of 200 nm laser light and a method to calculate the “risetime” for a square pulse and compare it with the computed electron transit time from the photocathode to the anode. Measured response time for 5 XRD-31s assembled in early 2004 was 149.7 ps +-2.75 ps.

  3. Wavelength calibration of x-ray imaging crystal spectrometer on Joint Texas Experimental Tokamak

    SciTech Connect (OSTI)

    Yan, W.; Chen, Z. Y., E-mail: zychen@hust.edu.cn; Jin, W.; Huang, D. W.; Ding, Y. H.; Li, J. C.; Zhang, X. Q.; Zhuang, G. [School of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan (China); Lee, S. G.; Shi, Y. J. [National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of)

    2014-11-15T23:59:59.000Z

    The wavelength calibration of x-ray imaging crystal spectrometer is a key issue for the measurements of plasma rotation. For the lack of available standard radiation source near 3.95 Å and there is no other diagnostics to measure the core rotation for inter-calibration, an indirect method by using tokamak plasma itself has been applied on joint Texas experimental tokamak. It is found that the core toroidal rotation velocity is not zero during locked mode phase. This is consistent with the observation of small oscillations on soft x-ray signals and electron cyclotron emission during locked-mode phase.

  4. 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.

  5. X-ray source assembly having enhanced output stability, and fluid stream analysis applications thereof

    DOE Patents [OSTI]

    Radley, Ian (Glenmont, NY); Bievenue, Thomas J. (Delmar, NY); Burdett, John H. (Charlton, NY); Gallagher, Brian W. (Guilderland, NY); Shakshober, Stuart M. (Hudson, NY); Chen, Zewu (Schenectady, NY); Moore, Michael D. (Alplaus, NY)

    2008-06-08T23:59:59.000Z

    An x-ray source assembly and method of operation are provided having enhanced output stability. The assembly includes an anode having a source spot upon which electrons impinge and a control system for controlling position of the anode source spot relative to an output structure. The control system can maintain the anode source spot location relative to the output structure notwithstanding a change in one or more operating conditions of the x-ray source assembly. One aspect of the disclosed invention is most amenable to the analysis of sulfur in petroleum-based fuels.

  6. X-ray source assembly having enhanced output stability, and fluid stream analysis applications thereof

    DOE Patents [OSTI]

    Radley, Ian; Bievenue, Thomas J.; Burdett Jr., John H.; Gallagher, Brian W.; Shakshober, Stuart M.; Chen, Zewu; Moore, Michael D.

    2007-04-24T23:59:59.000Z

    An x-ray source assembly (2700) and method of operation are provided having enhanced output stability. The assembly includes an anode (2125) having a source spot upon which electrons (2120) impinge and a control system (2715/2720) for controlling position of the anode source spot relative to an output structure. The control system can maintain the anode source spot location relative to the output structure (2710) notwithstanding a change in one or more operating conditions of the x-ray source assembly. One aspect of the disclosed invention is most amenable to the analysis of sulfur in petroleum-based fuels.

  7. Constraints on jet X-ray emission in low/hard state X-ray binaries

    E-Print Network [OSTI]

    Thomas J. Maccarone

    2005-03-31T23:59:59.000Z

    We show that the combination of the similarities between the X-ray properties of low luminosity accreting black holes and accreting neutron stars, combined with the differences in their radio properties argues that the X-rays from these systems are unlikely to be formed in the relativistic jets. Specifically, the spectra of extreme island state neutron stars and low/hard state black holes are known to be indistinguishable, while the power spectra from these systems are known to show only minor differences beyond what would be expected from scaling the characteristic variability frequencies by the mass of the compact object. The spectral and temporal similarities thus imply a common emission mechanism that has only minor deviations from having all key parameters scaling linearly with the mass of the compact object, while we show that this is inconsistent with the observations that the radio powers of neutron stars are typically about 30 times lower than those of black holes at the same X-ray luminosity. We also show that an abrupt luminosity change would be expected when a system makes a spectral state transition from a radiatively inefficient jet dominated accretion flow to a thin disk dominated flow, but that such a change is not seen.

  8. Isotropic star in low-mass X-ray binaries and X-ray pulsars

    E-Print Network [OSTI]

    Mehedi Kalam; Sk. Monowar Hossein; Sajahan Molla

    2014-10-01T23:59:59.000Z

    We present a model for compact stars in the low mass X-ray binaries(LMXBs) and X-ray pulsars using a metric given by John J. Matese and Patrick G. Whitman \\citep{Matese and Whitman1980}. Here the field equations are reduced to a system of two algebraic equations considering the isotropic pressure. Compact star candidates 4U 1820-30(radius=10km) in LMXBs, and Her X-1(radius=7.7km), SAX J 1808.4-3658(SS1)(radius=7.07km) and SAX J 1808.4-3658(SS2)(radius=6.35km) in X-ray pulsars satisfy all the energy conditions, TOV-equation and stability condition. From our model, we have derived mass($M$), central density($\\rho_{0}$), suface density($\\rho_{b}$), central pressure($p_{0}$), surface pressure($p_{b}$) and surface red-shift($Z_{s}$) of the above mentioned stars, which are very much consistant with the observed/reported datas\\citep{N. K. Glendenning1997,Gondek2000}. We have also observe the adiabatic index($\\gamma$>4/3) of the above steller objects.

  9. Cyclic olefin homopolymer-based microfluidics for protein crystallization and in situ X-ray diffraction

    SciTech Connect (OSTI)

    Emamzadah, Soheila [Department of Molecular Biology, University of Geneva, CH-1205 Geneva (Switzerland); Department of Biochemistry, University of Geneva, CH-1205 Geneva (Switzerland); Petty, Tom J. [Department of Molecular Biology, University of Geneva, CH-1205 Geneva (Switzerland); Biomedical Graduate Studies Genomics and Computational Biology Group, University of Pennsylvania, Philadelphia, PA 19104 (United States); De Almeida, Victor [Department of Molecular Biology, University of Geneva, CH-1205 Geneva (Switzerland); Department of Biochemistry, University of Geneva, CH-1205 Geneva (Switzerland); Nishimura, Taisuke [Department of Plant Biology, University of Geneva, CH-1205 Geneva (Switzerland); Joly, Jacques; Ferrer, Jean-Luc [Institut de Biologie Structurale J.-P. Ebel, CEA-CNRS-University J. Fourier, 38027 Grenoble CEDEX 1 (France); Halazonetis, Thanos D., E-mail: thanos.halazonetis@unige.ch [Department of Molecular Biology, University of Geneva, CH-1205 Geneva (Switzerland); Department of Biochemistry, University of Geneva, CH-1205 Geneva (Switzerland)

    2009-09-01T23:59:59.000Z

    A cyclic olefin homopolymer-based microfluidics system has been established for protein crystallization and in situ X-ray diffraction. Microfluidics is a promising technology for the rapid identification of protein crystallization conditions. However, most of the existing systems utilize silicone elastomers as the chip material which, despite its many benefits, is highly permeable to water vapour. This limits the time available for protein crystallization to less than a week. Here, the use of a cyclic olefin homopolymer-based microfluidics system for protein crystallization and in situ X-ray diffraction is described. Liquid handling in this system is performed in 2 mm thin transparent cards which contain 500 chambers, each with a volume of 320 nl. Microbatch, vapour-diffusion and free-interface diffusion protocols for protein crystallization were implemented and crystals were obtained of a number of proteins, including chicken lysozyme, bovine trypsin, a human p53 protein containing both the DNA-binding and oligomerization domains bound to DNA and a functionally important domain of Arabidopsis Morpheus’ molecule 1 (MOM1). The latter two polypeptides have not been crystallized previously. For X-ray diffraction analysis, either the cards were opened to allow mounting of the crystals on loops or the crystals were exposed to X-rays in situ. For lysozyme, an entire X-ray diffraction data set at 1.5 Å resolution was collected without removing the crystal from the card. Thus, cyclic olefin homopolymer-based microfluidics systems have the potential to further automate protein crystallization and structural genomics efforts.

  10. Residual stress measurement using X-ray diffraction 

    E-Print Network [OSTI]

    Anderoglu, Osman

    2005-02-17T23:59:59.000Z

    .3.6.2. Synchrotron Diffraction.........................................................................9 II. FUNDAMENTAL CONCEPTS IN X-RAY DIFFRACTION.....................................12 2.1. X-ray Source... radiations ...................................................................16 Table 2.2 Structure factors and reflection conditions ...................................................20 Table 4.1 Chemical composition of SS316...

  11. Ultrafast x-rays: radiographing magnetism Project overview

    E-Print Network [OSTI]

    Haviland, David

    , head of the ultrafast magnetism group. Stanford PULSE is a worldwide renowned centre for ultrafast1 Ultrafast x-rays: radiographing magnetism Project overview The main purpose of the proposed, it is now possible to achieve x-ray pulses that are a few femtoseconds long and that are focused within

  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. 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

  14. 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

  15. 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

  16. 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

  17. 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

  18. 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

  19. 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

  20. 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

  1. Electromagnetic Application: X-RAY Alawi H. Ba-Surrah

    E-Print Network [OSTI]

    Masoudi, Husain M.

    , Pulyui published high-quality x-ray images in journals in Paris and London. · Nikola Tesla In April 1887, Nikola Tesla began to investigate X-rays using high voltages and tubes of his own design, as well. The principle behind Tesla's device is called the Bremsstrahlung process, in which a high-energy secondary X

  2. Chandra X-ray Analysis of Galaxy Cluster A168

    E-Print Network [OSTI]

    Yanbin Yang; Zhiying Huo; Xu Zhou; Suijian Xue; Shude Mao; Jun Ma; Jiansheng Chen

    2004-06-29T23:59:59.000Z

    We present Chandra X-ray observations of galaxy cluster A168 (z=0.045). Two X-ray peaks with a projected distance of 676 kpc are found to be located close to two dominant galaxies, respectively. Both peaks are significantly offset from the peak of the number density distribution of galaxies. This suggests that A168 consists of two subclusters, a northern subcluster (A168N) and a southern subcluster (A168S). Further X-ray imaging analysis reveals that (1) the X-ray isophotes surrounding the two X-ray peaks are heavily distorted, (2) an elongated and ontinuous filament connects the two X-ray peaks. These suggest that strong interactions have occurred between the two subclusters. Spectral analysis shows that A168 has a mean temperature of 2.53 +/- 0.09 keV and a mean metallicity of 0.31 +/- 0.04 Z_{solar}. The metallicity is roughly a constant across the cluster but the temperature shows some systematic variations. Most X-ray, optical and radio properties of A168 are consistent with it being an off-axis merger several Gyrs after a core passage, although detailed numerical simulations are required to see whether the observed properties, in particular the significant offset between the optical and X-ray centers, can be reproduced in such a scenario.

  3. Millisecond oscillations during thermonuclear X-ray bursts

    E-Print Network [OSTI]

    Muno, Michael Patrick, 1975-

    2002-01-01T23:59:59.000Z

    I analyze 68 oscillation trains detected in a search of 159 thermonuclear bursts from eight neutron star X-ray binaries observed with the Rossi X-ray Timing Explorer. I use all data that were public as of September 2001. ...

  4. Hard X-ray Microscopic Images of the Human Hair

    SciTech Connect (OSTI)

    Goo, Jawoong; Jeon, Soo Young; Oh, Tak Heon; Hong, Seung Phil; Lee, Won-Soo [Department of Dermatology and Institute of Hair and Cosmetic Medicine, Yonsei University Wonju College of Medicine, Wonju (Korea, Republic of); Yon, Hwa Shik [Pohang Accelerator Laboratory, Pohang University of Science and Technology, Pohang (Korea, Republic of)

    2007-01-19T23:59:59.000Z

    The better visualization of the human organs or internal structure is challenging to the physicist and physicians. It can lead to more understanding of the morphology, pathophysiology and the diagnosis. Conventionally used methods to investigate cells or architectures, show limited value due to sample processing procedures and lower resolution. In this respect, Zernike type phase contrast hard x-ray microscopy using 6.95keV photon energy has advantages. We investigated hair fibers of the normal healthy persons. Coherence based phase contrast images revealed three distinct structures of hair, medulla, cortex, and cuticular layer. Some different detailed characters of each sample were noted. And further details would be shown and these results would be utilized as basic data of morphologic study of human hair.

  5. Transverse Coherence of the LCLS X-Ray Beam

    SciTech Connect (OSTI)

    Not Available

    2010-12-01T23:59:59.000Z

    Self-amplifying spontaneous radiation free-electron lasers, such as the LCLS or the European X-FEL, rely on the incoherent, spontaneous radiation as the seed for the amplifying process. Though this method overcomes the need for an external seed source one drawback is the incoherence of the effective seed signal. The FEL process allows for a natural growth of the coherence because the radiation phase information is spread out within the bunch due to slippage and diffraction of the radiation field. However, at short wavelengths this spreading is not sufficient to achieve complete coherence. In this presentation we report on the results of numerical simulations of the LCLS X-ray FEL. From the obtained radiation field distribution the coherence properties are extracted to help to characterize the FEL as a light source.

  6. Broadband high resolution X-ray spectral analyzer

    DOE Patents [OSTI]

    Silver, E.H.; Legros, M.; Madden, N.W.; Goulding, F.; Landis, D.

    1998-07-07T23:59:59.000Z

    A broad bandwidth high resolution X-ray fluorescence spectrometer has a performance that is superior in many ways to those currently available. It consists of an array of 4 large area microcalorimeters with 95% quantum efficiency at 6 keV and it produces X-ray spectra between 0.2 keV and 7 keV with an energy resolution of 7 to 10 eV. The resolution is obtained at input count rates per array element of 10 to 50 Hz in real-time, with analog pulse processing and thermal pile-up rejection. This performance cannot be matched by currently available X-ray spectrometers. The detectors are incorporated into a compact and portable cryogenic refrigerator system that is ready for use in many analytical spectroscopy applications as a tool for X-ray microanalysis or in research applications such as laboratory and astrophysical X-ray and particle spectroscopy. 6 figs.

  7. Broadband high resolution X-ray spectral analyzer

    DOE Patents [OSTI]

    Silver, Eric H. (Berkeley, CA); Legros, Mark (Berkeley, CA); Madden, Norm W. (Livermore, CA); Goulding, Fred (Lafayette, CA); Landis, Don (Pinole, CA)

    1998-01-01T23:59:59.000Z

    A broad bandwidth high resolution x-ray fluorescence spectrometer has a performance that is superior in many ways to those currently available. It consists of an array of 4 large area microcalorimeters with 95% quantum efficiency at 6 keV and it produces x-ray spectra between 0.2 keV and 7 keV with an energy resolution of 7 to 10 eV. The resolution is obtained at input count rates per array element of 10 to 50 Hz in real-time, with analog pulse processing and thermal pile-up rejection. This performance cannot be matched by currently available x-ray spectrometers. The detectors are incorporated into a compact and portable cryogenic refrigerator system that is ready for use in many analytical spectroscopy applications as a tool for x-ray microanalysis or in research applications such as laboratory and astrophysical x-ray and particle spectroscopy.

  8. 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.

  9. X-Ray Observations of Gamma-Ray Burst Afterglows

    E-Print Network [OSTI]

    Filippo Frontera

    2004-06-25T23:59:59.000Z

    The discovery by the BeppoSAX satellite of X-ray afterglow emission from the gamma-ray burst which occurred on 28 February 1997 produced a revolution in our knowledge of the gamma-ray burst phenomenon. Along with the discovery of X-ray afterglows, the optical afterglows of gamma-ray bursts were discovered and the distance issue was settled, at least for long $\\gamma$-ray bursts. The 30 year mystery of the gamma-ray burst phenomenon is now on the way to solution. Here I rewiew the observational status of the X-ray afterglow emission, its mean properties (detection rate, continuum spectra, line features, and light curves), and the X-ray constraints on theoretical models of gamma-ray bursters and their progenitors. I also discuss the early onset afterglow emission, the remaining questions, and the role of future X-ray afterglow observations.

  10. 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.

  11. 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)

  12. Three-dimensional x-ray fluorescence mapping of a gold nanoparticle-loaded phantom

    SciTech Connect (OSTI)

    Ren, Liqiang; Wu, Di; Li, Yuhua; Liu, Hong, E-mail: liu@ou.edu [Center for Bioengineering and School of Electrical and Computer Engineering, University of Oklahoma, Norman, Oklahoma 73019 (United States)] [Center for Bioengineering and School of Electrical and Computer Engineering, University of Oklahoma, Norman, Oklahoma 73019 (United States); Wang, Ge [Biomedical Imaging Cluster and Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)] [Biomedical Imaging Cluster and Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States); Wu, Xizeng [Department of Radiology, University of Alabama, Birmingham, Alabama 35233 (United States)] [Department of Radiology, University of Alabama, Birmingham, Alabama 35233 (United States)

    2014-03-15T23:59:59.000Z

    Purpose : X-ray fluorescence (XRF) is a promising technique with sufficient specificity and sensitivity for identifying and quantifying features in small samples containing high atomic number (Z) materials such as iodine, gadolinium, and gold. In this study, the feasibility of applying XRF to early breast cancer diagnosis and treatment is studied using a novel approach for three-dimensional (3D) x-ray fluorescence mapping (XFM) of gold nanoparticle (GNP)-loaded objects in a physical phantom at the technical level. Methods : All the theoretical analysis and experiments are conducted under the condition of using x-ray pencil beam and a compactly integrated x-ray spectrometer. The penetrability of the fluorescence x-rays from GNPs is first investigated by adopting a combination of BR12 with 70 mm/50 mm in thickness on the excitation/emission path to mimic the possible position of tumor goldin vivo. Then, a physical phantom made of BR12 is designed to translate in 3D space with three precise linear stages and subsequently the step by step XFM scanning is performed. The experimental technique named as background subtraction is applied to isolate the gold fluorescence from each spectrum obtained by the spectrometer. Afterwards, the attenuations of both the incident primary x-ray beam with energies beyond the gold K-edge energy (80.725 keV) and the isolated gold K{sub ?} fluorescence x-rays (65.99 –69.80 keV) acquired after background subtraction are well calibrated, and finally the unattenuated K{sub ?} fluorescence counts are used to realize mapping reconstruction and to describe the linear relationship between gold fluorescence counts and corresponding concentration of gold solutions. Results : The penetration results show that the goldK{sub ?} fluorescence x-rays have sufficient penetrability for this phantom study, and the reconstructed mapping results indicate that both the spatial distribution and relative concentration of GNPs within the designed BR12 phantom can be well identified and quantified. Conclusions : Although the XFM method in this investigation is still studied at the technical level and is not yet practical for routinein vivo mapping tasks with GNPs, the current penetrability measurements and phantom study strongly suggest the feasibility to establish and develop a 3D XFM system.

  13. High spatial resolution X-ray and gamma ray imaging system using diffraction crystals

    DOE Patents [OSTI]

    Smither, Robert K. (Hinsdale, IL)

    2011-05-17T23:59:59.000Z

    A method and a device for high spatial resolution imaging of a plurality of sources of x-ray and gamma-ray radiation are provided. The device comprises a plurality of arrays, with each array comprising a plurality of elements comprising a first collimator, a diffracting crystal, a second collimator, and a detector.

  14. PERTURBATION-BASED ERROR ANALYSIS OF ITERATIVE IMAGE RECONSTRUCTION ALGORITHM FOR X-RAY COMPUTED TOMOGRAPHY

    E-Print Network [OSTI]

    Fessler, Jeffrey A.

    -ray computed tomography. The effects of the quantization error in forward-projection, back computed tomography (CT) have been proposed to improve image quality and reduce dose [1]. These methodsPERTURBATION-BASED ERROR ANALYSIS OF ITERATIVE IMAGE RECONSTRUCTION ALGORITHM FOR X-RAY COMPUTED

  15. Electron beam-based sources of ultrashort x-ray pulses.

    SciTech Connect (OSTI)

    Zholents, A.; Accelerator Systems Division (APS)

    2010-09-30T23:59:59.000Z

    A review of various methods for generation of ultrashort x-ray pulses using relativistic electron beam from conventional accelerators is presented. Both spontaneous and coherent emission of electrons is considered. The importance of the time-resolved studies of matter at picosecond (ps), femtosecond (fs), and atttosecond (as) time scales using x-rays has been widely recognized including by award of a Nobel Prize in 1999 [Zewa]. Extensive reviews of scientific drivers can be found in [BES1, BES2, BES3, Lawr, Whit]. Several laser-based techniques have been used to generate ultrashort x-ray pulses including laser-driven plasmas [Murn, Alte, Risc, Rose, Zamp], high-order harmonic generation [Schn, Rund, Wang, Arpi], and laser-driven anode sources [Ande]. In addition, ultrafast streak-camera detectors have been applied at synchrotron sources to achieve temporal resolution on the picosecond time scale [Wulf, Lind1]. In this paper, we focus on a different group of techniques that are based on the use of the relativistic electron beam produced in conventional accelerators. In the first part we review several techniques that utilize spontaneous emission of electrons and show how solitary sub-ps x-ray pulses can be obtained at existing storage ring based synchrotron light sources and linacs. In the second part we consider coherent emission of electrons in the free-electron lasers (FELs) and review several techniques for a generation of solitary sub-fs x-ray pulses. Remarkably, the x-ray pulses that can be obtained with the FELs are not only significantly shorter than the ones considered in Part 1, but also carry more photons per pulse by many orders of magnitude.

  16. 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.

  17. A refined model for characterizing x-ray multilayers

    SciTech Connect (OSTI)

    Oren, A.L.; Henke, B.L.

    1987-12-01T23:59:59.000Z

    The ability to quickly and accurately characterize arbitrary multilayers is very valuable for not only can we use the characterizations to predict the reflectivity of a multilayer for any soft x-ray wavelength, we also can generalize the results to apply to other multilayers of the same type. In addition, we can use the characterizations as a means of evaluating various sputtering environments and refining sputtering techniques to obtain better multilayers. In this report we have obtained improved characterizations for sample molybdenum-silicon and vanadium-silicon multilayers. However, we only examined five crystals overall, so the conclusions that we could draw about the structure of general multilayers is limited. Research involving many multilayers manufactured under the same sputtering conditions is clearly in order. In order to best understand multilayer structures it may be necessary to further refine our model, e.g., adopting a Gaussian form for the interface regions. With such improvements we can expect even better agreement with experimental values and continued concurrence with other characterization techniques. 18 refs., 30 figs., 7 tabs.

  18. SURFACE SEGREGATION STUDIES OF SOFC CATHODES: COMBINING SOFT X-RAYS AND ELECTROCHEMICAL IMPEDENCE SPECTROSCOPY

    SciTech Connect (OSTI)

    Miara, Lincoln J.; Piper, L.F.J.; Davis, Jacob N.; Saraf, Laxmikant V.; Kaspar, Tiffany C.; Basu, Soumendra; Smith, K. E.; Pal, Uday B.; Gopalan, Srikanth

    2010-12-01T23:59:59.000Z

    A system to grow heteroepitaxial thin-films of solid oxide fuel cell (SOFC) cathodes on single crystal substrates was developed. The cathode composition investigated was 20% strontium-doped lanthanum manganite (LSM) grown by pulsed laser deposition (PLD) on single crystal (111) yttria-stabilized zirconia (YSZ) substrates. By combining electrochemical impedance spectroscopy (EIS) with x-ray photoemission spectroscopy (XPS) and x-ray absorption spectroscopy XAS measurements, we conclude that electrically driven cation migration away from the two-phase gas-cathode interface results in improved electrochemical performance. Our results provide support to the premise that the removal of surface passivating phases containing Sr2+ and Mn2+, which readily form at elevated temperatures even in O2 atmospheric pressures, is responsible for the improved cathodic performance upon application of a bias.

  19. 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.

  20. X-ray photoelectron spectroscopy of gallium nitride films grown by radical-beam gettering epitaxy

    SciTech Connect (OSTI)

    Rogozin, I. V. [Berdyansk State Pedagogical University (Ukraine)], E-mail: rogozin@bdpu.org; Kotlyarevsky, M. B. [Academy of Management and Information Technology (Ukraine)

    2007-05-15T23:59:59.000Z

    Thin GaN films were grown on GaAs(111) substrates by radical-beam gettering epitaxy. The structural quality of the films was studied by high-resolution x-ray diffraction. The chemical composition of the GaAs surface and GaN film was studied by x-ray photoelectron spectroscopy. It is shown that Ga-N and As-N bonds are formed on the GaAs surface at initial growth stages at low temperatures. The state of the film-substrate interface was studied. It was found that prolonged annealing of GaN films in nitrogen radicals shifts the composition to nitrogen excess.

  1. X-ray Emission from Massive StarsX-ray Emission from Massive Stars David CohenDavid Cohen

    E-Print Network [OSTI]

    Cohen, David

    X-ray Emission from Massive StarsX-ray Emission from Massive Stars David CohenDavid Cohen/s)Velocity (km/s) #12;absorption emission emission occulted emission emission UV telescope side side front back #12;absorption emission emission occulted emission emission UV telescope side side front back #12;The

  2. AugEX: AUGER ELECTRON AND X-RAY SPECTROMETER ON CHANDRAYAAN-2 ROVER

    E-Print Network [OSTI]

    Bapat, Bhas

    for determining elemental composition which have a space heritage X-Ray Fluorescence (XRF) Particle-induced X-ray fluorescence (XRF) Expected Advantage: cover low Z elements with higher sensitivity than XRF or PIXE. ACHARYA-ray absorption or charged particle bombardment X-ray emission induced by X-ray absorption: XRF X-ray emission

  3. In-situ X-ray absorption spectroscopy analysis of capacity fade in nanoscale-LiCoO{sub 2}

    SciTech Connect (OSTI)

    Patridge, Christopher J. [NRC/NRL Cooperative Research Associate, U.S. Naval Research Laboratory, Washington, DC 20375 (United States); Love, Corey T., E-mail: corey.love@nrl.navy.mil [Chemistry Division, Code 6113, U.S. Naval Research Laboratory, Washington, DC 20375 (United States); Swider-Lyons, Karen E. [Chemistry Division, Code 6113, U.S. Naval Research Laboratory, Washington, DC 20375 (United States); Twigg, Mark E. [Electronics Science and Technology Division, Code 6812, U.S. Naval Research Laboratory, Washington, DC 20375 (United States); Ramaker, David E. [Chemistry Division, Code 6189, U.S. Naval Research laboratory, Washington, DC 20375 (United States)

    2013-07-15T23:59:59.000Z

    The local structure of nanoscale (?10–40 nm) LiCoO{sub 2} is monitored during electrochemical cycling utilizing in-situ X-ray absorption spectroscopy (XAS). The high surface area of the LiCoO{sub 2} nanoparticles not only enhances capacity fade, but also provides a large signal from the particle surface relative to the bulk. Changes in the nanoscale LiCoO{sub 2} metal-oxide bond lengths, structural disorder, and chemical state are tracked during cycling by adapting the delta mu (??) technique in complement with comprehensive extended X-ray absorption fine structure (EXAFS) modeling. For the first time, we use a ?? EXAFS method, and by comparison of the difference EXAFS spectra, extrapolate significant coordination changes and reduction of cobalt species with cycling. This combined approach suggests Li–Co site exchange at the surface of the nanoscale LiCoO{sub 2} as a likely factor in the capacity fade and irreversible losses in practical, microscale LiCoO{sub 2}. - Graphical abstract: Electrochemical cycling of Li-ion batteries has strong impact on the structure and integrity of the cathode active material particularly near the surface/electrolyte interface. In developing a new method, we have used in-situ X-ray absorption spectroscopy during electrochemical cycling of nanoscale LiCoO{sub 2} to track changes during charge and discharge and between subsequent cycles. Using difference spectra, several small changes in Co-O bond length, Co-O and Co-Co coordination, and site exchange between Co and Li sites can be tracked. These methods show promise as a new technique to better understand processes which lead to capacity fade and loss in Li-ion batteries. - Highlights: • A new method is developed to understand capacity fade in Li-ion battery cathodes. • Structural changes are tracked during Li intercalation/deintercalation of LiCoO{sub 2}. • Surface structural changes are emphasized using nanoscale-LiCoO{sub 2} and difference spectra. • Full multiple scattering calculations are used to support ?? analysis.

  4. Comparison of SOFC Cathode Microstructure Quantified using X-ray Nanotomography and Focused Ioni Beam-scanning Electron Microscopy

    SciTech Connect (OSTI)

    G Nelson; W Harris; J Lombardo; J Izzo Jr.; W Chiu; P Tanasini; M Cantoni; J Van herle; C Comninellis; et al.

    2011-12-31T23:59:59.000Z

    X-ray nanotomography and focused ion beam scanning electron microscopy (FIB-SEM) have been applied to investigate the complex 3D microstructure of solid oxide fuel cell (SOFC) electrodes at spatial resolutions of 45 nm and below. The application of near edge differential absorption for x-ray nanotomography and energy selected backscatter detection for FIB-SEM enable elemental mapping within the microstructure. Using these methods, non-destructive 3D x-ray imaging and FIB-SEM serial sectioning have been applied to compare three-dimensional elemental mapping of the LSM, YSZ, and pore phases in the SOFC cathode microstructure. The microstructural characterization of an SOFC cathode is reported based on these measurements. The results presented demonstrate the viability of x-ray nanotomography as a quantitative characterization technique and provide key insights into the SOFC cathode microstructure.

  5. Comparison of SOFC Cathode Microstructure Quantified using X-ray Nanotomography and Focused Ion Beam - Scanning Electron Microscopy

    SciTech Connect (OSTI)

    Nelson, George J.; Harris, William H.; Lombardo, Jeffrey J.; Izzo, Jr., John R.; Chiu, W. K. S.; Tanasini, Pietro; cantoni, Marco; Van herle, Jan; Comninellis, Christos; Andrews, Joy C.; Liu, Yijin; Pianetta, Piero; Chu, Yong

    2011-01-01T23:59:59.000Z

    X-ray nanotomography and focused ion beam scanning electron microscopy (FIB?SEM) have been applied to investigate the complex 3D microstructure of solid oxide fuel cell (SOFC) electrodes at spatial resolutions of 45 nm and below. The application of near edge differential absorption for x-ray nanotomography and energy selected backscatter detection for FIB–SEM enable elemental mapping within the microstructure. Using these methods, non?destructive 3D x-ray imaging and FIB–SEM serial sectioning have been applied to compare three?dimensional elemental mapping of the LSM, YSZ, and pore phases in the SOFC cathode microstructure. The microstructural characterization of an SOFC cathode is reported based on these measurements. The results presented demonstrate the viability of x-ray nanotomography as a quantitative characterization technique and provide key insights into the SOFC cathode microstructure.

  6. X-ray Computed Tomography of coal: Final report

    SciTech Connect (OSTI)

    Maylotte, D.H.; Spiro, C.L.; Kosky, P.G.; Lamby, E.J.

    1986-12-01T23:59:59.000Z

    X-ray Computed Tomography (CT) is a method of mapping with x-rays the internal structures of coal. The technique normally produces 2-D images of the internal structures of an object. These images can be recast to create pseudo 3-D representations. CT of coal has been explored for a variety of different applications to coal and coal processing technology. In a comparison of CT data with conventional coal analyses and petrography, CT was found to offer a good indication of the total ash content of the coal. The spatial distribution of the coal mineral matter as seen with CT has been suggested as an indicator of coal washability. Studies of gas flow through coal using xenon gas as a tracer have shown the extremely complicated nature of the modes of penetration of gas through coal, with significant differences in the rates at which the gas can pass along and across the bedding planes of coal. In a special furnace designed to allow CT images to be taken while the coal was being heated, the pyrolysis and gasification of coal have been studied. Gasification rates with steam and CO/sub 2/ for a range of coal ranks have been obtained, and the location of the gasification reactions within the piece of coal can be seen. Coal drying and the progress of the pyrolysis wave into coal have been examined when the coal was subjected to the kind of sudden temperature jump that it might experience in fixed bed gasifier applications. CT has also been used to examine stable flow structures within model fluidized beds and the accessibility of lump coal to microbial desulfurization. 53 refs., 242 figs., 26 tabs.

  7. Protein crystallography: From X-ray diffraction spots to a three dimensional image

    SciTech Connect (OSTI)

    Terwilliger, T.C.; Berendzen, J.

    1998-02-25T23:59:59.000Z

    Proteins are remarkable molecular machines that are essential for life. They can do many things ranging from the precise control of blood clotting to synthesizing complex organic compounds. Pictures of protein molecules are in high demand in biotechnology because they are important for applications such as drug discovery and for engineering enzymes for commercial use. X-ray crystallography is the most common method for determining the three-dimensional structures of protein molecules. When a crystal of a protein is placed in an X-ray beam, scattering of X-rays off the ordered molecules produces a diffraction pattern that can be measured on a position-sensitive CCD or image-plate detector. Protein crystals typically contain thousands of atoms and the diffraction data are generally measured to relatively low resolution. Consequently the direct methods approaches generally cannot be applied. Instead, if the crystal is modified by adding metal atoms at specific sites or by tuning the wavelength of the X-rays to cross an absorption edge of a metal atom in the crystal, then the information from these additional measurements is sufficient to first identify the /locations of the metal atoms. This information is then used along with the diffraction data to make a three-dimensional picture of electron densities. This picture can be used to determine the position of most or all of the atoms in the protein.

  8. 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.

  9. 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.

  10. Spatiotemporal focusing dynamics in plasmas at X-ray wavelength

    SciTech Connect (OSTI)

    Sharma, A., E-mail: a-physics2001@yahoo.com; Tibai, Z. [Institute of Physics, University of Pecs, Pecs–7624 (Hungary)] [Institute of Physics, University of Pecs, Pecs–7624 (Hungary); Hebling, J. [Institute of Physics, University of Pecs, Pecs–7624 (Hungary) [Institute of Physics, University of Pecs, Pecs–7624 (Hungary); Szentagothai Research Centre, University of Pecs, Pecs-7624 (Hungary); Mishra, S. K. [Institute for Plasma Research, Gandhinagar (India)] [Institute for Plasma Research, Gandhinagar (India)

    2014-03-15T23:59:59.000Z

    Using a finite curvature beam, we investigate here the spatiotemporal focusing dynamics of a laser pulse in plasmas at X-ray wavelength. We trace the dependence of curvature parameter on the focusing of laser pulse and recognize that the self-focusing in plasma is more intense for the X-ray laser pulse with curved wavefront than with flat wavefront. The simulation results demonstrate that spatiotemporal focusing dynamics in plasmas can be controlled with the appropriate choice of beam-plasma parameters to explore the high intensity effects in X-ray regime.

  11. X-ray backscatter imaging of nuclear materials

    DOE Patents [OSTI]

    Chapman, Jeffrey Allen; Gunning, John E; Hollenbach, Daniel F; Ott, Larry J; Shedlock, Daniel

    2014-09-30T23:59:59.000Z

    The energy of an X-ray beam and critical depth are selected to detect structural discontinuities in a material having an atomic number Z of 57 or greater. The critical depth is selected by adjusting the geometry of a collimator that blocks backscattered radiation so that backscattered X-ray originating from a depth less than the critical depth is not detected. Structures of Lanthanides and Actinides, including nuclear fuel rod materials, can be inspected for structural discontinuities such as gaps, cracks, and chipping employing the backscattered X-ray.

  12. Gated x-ray detector for the National Ignition Facility

    SciTech Connect (OSTI)

    Oertel, John A.; Aragonez, Robert; Archuleta, Tom; Barnes, Cris; Casper, Larry; Fatherley, Valerie; Heinrichs, Todd; King, Robert; Landers, Doug; Lopez, Frank; Sanchez, Phillip; Sandoval, George; Schrank, Lou; Walsh, Peter; Bell, Perry; Brown, Matt; Costa, Robert; Holder, Joe; Montelongo, Sam; Pederson, Neal [Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States); Lawrence Livermore National Laboratory, Livermore, California 94551-0808 (United States); VI Control Systems Ltd., Los Alamos, New Mexico 87544 (United States)

    2006-10-15T23:59:59.000Z

    Two new gated x-ray imaging cameras have recently been designed, constructed, and delivered to the National Ignition Facility in Livermore, CA. These gated x-Ray detectors are each designed to fit within an aluminum airbox with a large capacity cooling plane and are fitted with an array of environmental housekeeping sensors. These instruments are significantly different from earlier generations of gated x-ray images due, in part, to an innovative impedance matching scheme, advanced phosphor screens, pulsed phosphor circuits, precision assembly fixturing, unique system monitoring, and complete remote computer control. Preliminary characterization has shown repeatable uniformity between imaging strips, improved spatial resolution, and no detectable impedance reflections.

  13. X-ray afterglows from gamma-ray bursts

    E-Print Network [OSTI]

    M. Tavani

    1997-03-24T23:59:59.000Z

    We consider possible interpretations of the recently detected X- ray afterglow from the gamma-ray burst source GRB 970228. Cosmological and Galactic models of gamma-ray bursts predict different flux and spectral evolution of X-ray afterglows. We show that models based on adiabatic expansion of relativistic forward shocks require very efficient particle energization or post-burst re-acceleration during the expansion. Cooling neutron star models predict a very distinctive spectral and flux evolution that can be tested in current X-ray data.

  14. 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.

  15. X-ray Diffraction from Membrane Protein Nanocrystals

    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-RayX-ray

  16. Automated suppression of errors in LTP-II slope measurements with x-ray optics

    E-Print Network [OSTI]

    Ali, Zulfiqar

    2011-01-01T23:59:59.000Z

    slope measurements with x-ray optics Zulfiqar Ali, Curtis L.with state-of-the-art x-ray optics. Significant suppressionscanning, metrology of x-ray optics, deflectometry Abstract

  17. X-ray optics metrology limited by random noise, instrumental drifts, and systematic errors

    E-Print Network [OSTI]

    Yashchuk, Valeriy V.

    2010-01-01T23:59:59.000Z

    X-ray optics metrology limited by random noise, instrumentalUSA Center for X-ray Optics, Lawrence Berkeley Nationaland reflecting x-ray optics suitable for micro- and nano-

  18. atf compton x-ray: Topics by E-print Network

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

    D; Fritzsche, S 2014-01-01 14 Photospheres, Comptonization and X-ray Lines in Gamma Ray Bursts Astrophysics (arXiv) Summary: Steep X-ray spectral slopes, X-ray excesses and...

  19. adc x-ray binary: Topics by E-print Network

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

    systems. Sudip Bhattacharyya 2010-02-24 17 X-ray Transients from X-ray Binaries to Gamma Ray Bursts CERN Preprints Summary: We discuss three classes of x-ray transients to...

  20. Radiation exposure in X-ray-based imaging techniques used in osteoporosis

    E-Print Network [OSTI]

    Damilakis, John; Adams, Judith E.; Guglielmi, Giuseppe; Link, Thomas M.

    2010-01-01T23:59:59.000Z

    and nonradiologists in dual-energy X-ray absorptiometrymorphometry studies using dual-energy X-ray absorptiometry.dose measurements in dual energy X-ray absorptiometry (DXA).

  1. Lensless Imaging of Whole Biological Cells with Soft X-Rays

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

    Cells with Soft X-Rays Lensless Imaging of Whole Biological Cells with Soft X-Rays Print Wednesday, 26 May 2010 00:00 A team of scientists has used x-ray diffraction...

  2. Beyond 3-D X-ray Imaging: Methodology Development and Applications...

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

    to the availability of the new generation of X-ray sources and the advanced X-ray optics. The advanced X-ray Optics along with novel methodology has made it possible to...

  3. Methods and systems for monitoring a solid-liquid interface

    DOE Patents [OSTI]

    Stoddard, Nathan G. (Gettysburg, PA); Clark, Roger F. (Frederick, MD); Kary, Tim (Union Bridge, MD)

    2010-07-20T23:59:59.000Z

    Methods and systems are provided for monitoring a solid-liquid interface, including providing a vessel configured to contain an at least partially melted material; detecting radiation reflected from a surface of a liquid portion of the at least partially melted material that is parallel with the liquid surface; measuring a disturbance on the surface; calculating at least one frequency associated with the disturbance; and determining a thickness of the liquid portion based on the at least one frequency, wherein the thickness is calculated based on.times. ##EQU00001## where g is the gravitational constant, w is the horizontal width of the liquid, and f is the at least one frequency.

  4. High-rate x-ray spectroscopy in mammography with a CdTe detector: A digital pulse processing approach

    SciTech Connect (OSTI)

    Abbene, L.; Gerardi, G.; Principato, F.; Del Sordo, S.; Ienzi, R.; Raso, G. [Dipartimento di Fisica e Tecnologie Relative, Universita di Palermo, Viale delle Scienze, Edificio 18, Palermo 90128 (Italy) and INAF/IASF Palermo, Via Ugo La Malfa 153, 90146 Palermo (Italy); Dipartimento di Fisica e Tecnologie Relative, Universita di Palermo, Viale delle Scienze, Edificio 18, Palermo 90128 (Italy); INAF/IASF Palermo, Via Ugo La Malfa 153, 90146 Palermo (Italy); Istituto di Radiologia, Policlinico, 90100 Palermo (Italy); Dipartimento di Fisica e Tecnologie Relative, Universita di Palermo, Viale delle Scienze, Edificio 18, Palermo 90128 (Italy)

    2010-12-15T23:59:59.000Z

    Purpose:Direct measurement of mammographic x-ray spectra under clinical conditions is a difficult task due to the high fluence rate of the x-ray beams as well as the limits in the development of high resolution detection systems in a high counting rate environment. In this work we present a detection system, based on a CdTe detector and an innovative digital pulse processing (DPP) system, for high-rate x-ray spectroscopy in mammography. Methods: The DPP system performs a digital pile-up inspection and a digital pulse height analysis of the detector signals, digitized through a 14-bit, 100 MHz digitizer, for x-ray spectroscopy even at high photon counting rates. We investigated on the response of the digital detection system both at low (150 cps) and at high photon counting rates (up to 500 kcps) by using monoenergetic x-ray sources and a nonclinical molybdenum anode x-ray tube. Clinical molybdenum x-ray spectrum measurements were also performed by using a pinhole collimator and a custom alignment device. Results: The detection system shows excellent performance up to 512 kcps with an energy resolution of 4.08% FWHM at 22.1 keV. Despite the high photon counting rate (up to 453 kcps), the molybdenum x-ray spectra, measured under clinical conditions, are characterized by a low number of pile-up events. The agreement between the attenuation curves and the half value layer values, obtained from the measured spectra, simulated spectra, and from the exposure values directly measured with an ionization chamber, also shows the accuracy of the measurements. Conclusions: These results make the proposed detection system a very attractive tool for both laboratory research and advanced quality controls in mammography.

  5. Hybrid immersed interface-immersed boundary methods for AC dielectrophoresis

    SciTech Connect (OSTI)

    Hossan, Mohammad Robiul [School of Mechanical and Materials Engineering, Washington State University, Pullman, WA 99164-2920 (United States); Department of Engineering and Physics, University of Central Oklahoma, Edmond, OK 73034-5209 (United States); Dillon, Robert [Department of Mathematics, Washington State University, Pullman, WA 99164-3113 (United States); Dutta, Prashanta, E-mail: dutta@mail.wsu.edu [School of Mechanical and Materials Engineering, Washington State University, Pullman, WA 99164-2920 (United States)

    2014-08-01T23:59:59.000Z

    Dielectrophoresis, a nonlinear electrokinetic transport mechanism, has become popular in many engineering applications including manipulation, characterization and actuation of biomaterials, particles and biological cells. In this paper, we present a hybrid immersed interface–immersed boundary method to study AC dielectrophoresis where an algorithm is developed to solve the complex Poisson equation using a real variable formulation. An immersed interface method is employed to obtain the AC electric field in a fluid media with suspended particles and an immersed boundary method is used for the fluid equations and particle transport. The convergence of the proposed algorithm as well as validation of the hybrid scheme with experimental results is presented. In this paper, the Maxwell stress tensor is used to calculate the dielectrophoretic force acting on particles by considering the physical effect of particles in the computational domain. Thus, this study eliminates the approximations used in point dipole methods for calculating dielectrophoretic force. A comparative study between Maxwell stress tensor and point dipole methods for computing dielectrophoretic forces are presented. The hybrid method is used to investigate the physics of dielectrophoresis in microfluidic devices using an AC electric field. The numerical results show that with proper design and appropriate selection of applied potential and frequency, global electric field minima can be obtained to facilitate multiple particle trapping by exploiting the mechanism of negative dielectrophoresis. Our numerical results also show that electrically neutral particles form a chain parallel to the applied electric field irrespective of their initial orientation when an AC electric field is applied. This proposed hybrid numerical scheme will help to better understand dielectrophoresis and to design and optimize microfluidic devices.

  6. Interpreting the X-ray state transitions of Cygnus X-1

    E-Print Network [OSTI]

    ?echura, Jan; Hadrava, Petr

    2015-01-01T23:59:59.000Z

    We present a novel method for interpreting observations of high-mass X-ray binaries (HMXBs) based on a combination of spectroscopic data and numerical results from a radiation hydrodynamic model of stellar winds. We calculate synthetic Doppler tomograms of predicted emission in low/hard and high/soft X-ray states and compare them with Doppler tomograms produced using spectra of Cygnus X-1, a prototype of HMXBs. Emission from HMXBs is determined by local conditions within the circumstellar medium, namely density, temperature, and ionization state. These quantities depend strongly on the X-ray state of the systems. By increasing intensity of an X-ray emission produced by the compact companion in the HMXB model, we achieved a complete redistribution of the circumstellar medium in the vicinity of the modelled system. These changes (which simulate the transitions between two major spectral states) are also apparent in the synthetic Doppler tomograms which are in good agreement with the observations.

  7. Statistics of gravitational potential perturbations: A novel approach to deriving the X-ray temperature function

    E-Print Network [OSTI]

    Christian Angrick; Matthias Bartelmann

    2009-01-26T23:59:59.000Z

    Context. While the halo mass function is theoretically a very sensitive measure of cosmological models, masses of dark-matter halos are poorly defined, global, and unobservable quantities. Aims. We argue that local, observable quantities such as the X-ray temperatures of galaxy clusters can be directly compared to theoretical predictions without invoking masses. We derive the X-ray temperature function directly from the statistics of Gaussian random fluctuations in the gravitational potential. Methods. We derive the abundance of potential minima constrained by the requirement that they belong to linearly collapsed structures. We then use the spherical-collapse model to relate linear to non-linear perturbations, and the virial theorem to convert potential depths to temperatures. No reference is made to mass or other global quantities in the derivation. Results. Applying a proper high-pass filter that removes large enough modes from the gravitational potential, we derive an X-ray temperature function that agrees very well with the classical Press-Schechter approach on relevant temperature scales, but avoids the necessity of measuring masses. Conclusions. TThis first study shows that and how an X-ray temperature function of galaxy clusters can be analytically derived, avoiding the introduction of poorly defined global quantities such as halo masses. This approach will be useful for reducing scatter in observed cluster distributions and thus in cosmological conclusions drawn from them.

  8. Comptonization and the Spectra of Accretion-Powered X-Ray Pulsars

    E-Print Network [OSTI]

    Michael T. Wolff; Peter A. Becker; Kenneth D. Wolfram

    2007-04-17T23:59:59.000Z

    Accretion-powered X-ray pulsars are among the most luminous X-ray sources in the Galaxy. However, despite decades of theoretical and observational work since their discovery, no satisfactory model for the formation of the observed X-ray spectra has emerged. In this paper, we report on a self-consistent calculation of the spectrum emerging from a pulsar accretion column that includes an explicit treatment of the bulk and thermal Comptonization occurring in the radiation-dominated shocks that form in the accretion flows. Using a rigorous eigenfunction expansion method, we obtain a closed-form expression for the Green's function describing the upscattering of monochromatic radiation injected into the column. The Green's function is convolved with bremsstrahlung, cyclotron, and blackbody source terms to calculate the emergent photon spectrum. We show that energization of photons in the shock naturally produces an X-ray spectrum with a relatively flat continuum and a high-energy exponential cutoff. Finally, we demonstrate that our model yields good agreement with the spectra of the bright pulsar Her X-1 and the low luminosity pulsar X Per.

  9. How Can X-ray Transient Absorption Spectroscopy Aide Solar Energy...

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

    are from optimized on structural, energetic and dynamic parameters. Intense X-ray pulses from synchrotrons and X-ray free electrons lasers coupled with ultrafast lasers...

  10. X-rays only when you want them: Report on Pseudo-single-bunch...

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

    Speaker: David Robin, Lawrence Berkeley National Laboratory Program Description Laser pump - x-ray probe experiments require control over the x-ray pulse pattern and timing. Such...

  11. Scanning X-ray Microscopy Investigations into the Electron Beam Exposure Mechanism of Hydrogen Silsesquioxane Resists

    E-Print Network [OSTI]

    Olynick, Deirdre L.; Tivanski, Alexei V.; Gilles, Mary K.; Tyliszczak, Tolek; Salmassi, Farhad; Liddle, J. Alexander

    2006-01-01T23:59:59.000Z

    Scanning X-ray Microscopy Investigations into the Electronchemistry is investigated by Scanning Transmission X-raythe area exposed. 15 Recently, scanning transmission x-ray

  12. Soft X-Ray Microscopy and Spectroscopy at the Molecular Environmental...

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

    Soft X-Ray Microscopy and Spectroscopy at the Molecular Environmental Science Beamline at the Advanced Light Source. Soft X-Ray Microscopy and Spectroscopy at the Molecular...

  13. X-Ray Fluorescence (XRF) Analysis of Obsidian Artifacts from Shoofly Ruin, Central Arizona

    E-Print Network [OSTI]

    Shackley, M. Steven

    1986-01-01T23:59:59.000Z

    X-RAY FLUORESCENCE (XRF) ANALYSIS OF OBSIDIAN ARTIFACTS FROM62:426-437. SOUTHWEST XRF PAPER Table 1. X-ray fluorescence

  14. Using Light to Control How X Rays Interact with Matter

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

    Using Light to Control How X Rays Interact with Matter Print Schemes that use one light pulse to manipulate interactions of another with matter are well developed in the...

  15. In situ X-ray Characterization of Energy Storage Materials |...

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

    X-ray Characterization of Energy Storage Materials Tuesday, July 9, 2013 - 11:00am SLAC, Conference Room 137-322 Presented by Johanna Nelson, Stanford Postdoctoral Scholar, SSRL...

  16. Streaked x-ray microscopy of laser-fusion targets

    SciTech Connect (OSTI)

    Price, R.H.; Campbell, E.M.; Rosen, M.D.; Auerbach, J.M.; Phillion, D.W.; Whitlock, R.R.; Obenshain, S.P.; McLean, E.A.; Ripin, B.H.

    1982-08-01T23:59:59.000Z

    An ultrafast soft x-ray streak camera has been coupled to a Wolter axisymmetric x-ray microscope. This system was used to observe the dynamics of laser fusion targets both in self emission and backlit by laser produced x-ray sources. Spatial resolution was 7 ..mu..m and temporal resolution was 20 ps. Data is presented showing the ablative acceleration of foils to velocities near 10/sup 7/ cm/sec and the collision of an accelerated foil with a second foil, observed using 3 keV streaked x-ray backlighting. Good agreement was found between hydrocode simulations, simple models of the ablative acceleration and the observed velocities of the carbon foils.

  17. 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,...

  18. 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...

  19. 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...

  20. The Identification Problem for the attenuated X-ray transform

    E-Print Network [OSTI]

    2013-11-16T23:59:59.000Z

    X-ray transform has been solved in [27], see also [15]. The main result in .... For any compact set K ? T2, we define Hs(K) to be the closed subspace of Hs(T2) of

  1. 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.

  2. X-ray ptychography, fluorescence microscopy combo sheds new light...

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

    advance required the high brightness of the APS as an X-ray source and points the way to advances that can be expected as it is planned to be increased a hundredfold in the...

  3. Vitreous carbon mask substrate for X-ray lithography

    DOE Patents [OSTI]

    Aigeldinger, Georg (Livermore, CA); Skala, Dawn M. (Fremont, CA); Griffiths, Stewart K. (Livermore, CA); Talin, Albert Alec (Livermore, CA); Losey, Matthew W. (Livermore, CA); Yang, Chu-Yeu Peter (Dublin, CA)

    2009-10-27T23:59:59.000Z

    The present invention is directed to the use of vitreous carbon as a substrate material for providing masks for X-ray lithography. The new substrate also enables a small thickness of the mask absorber used to pattern the resist, and this enables improved mask accuracy. An alternative embodiment comprised the use of vitreous carbon as a LIGA substrate wherein the VC wafer blank is etched in a reactive ion plasma after which an X-ray resist is bonded. This surface treatment provides a surface enabling good adhesion of the X-ray photoresist and subsequent nucleation and adhesion of the electrodeposited metal for LIGA mold-making while the VC substrate practically eliminates secondary radiation effects that lead to delamination of the X-ray resist form the substrate, the loss of isolated resist features, and the formation of a resist layer adjacent to the substrate that is insoluble in the developer.

  4. Performance enhancement approaches for a dual energy x-ray

    E-Print Network [OSTI]

    Fu, Kenneth

    2010-01-01T23:59:59.000Z

    Evans, J.P.O. , “Stereoscopic dual energy imaging for targetCrawford, C.R. , “Dual Energy Volumetric X-ray Tomographicimages in 4–10 MeV Dual- energy customs system for material

  5. X-Ray Diffraction Microscopy of Magnetic Structures

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

    12.0.2.2 Citation: J.J. Turner et al., "X-Ray Diffraction Microscopy of Magnetic Structures," Phys. Rev. Lett. 107, 033904 (2011). Web: http:prl.aps.orgpdfPRLv107i3e033904...

  6. 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...

  7. Towards attosecond X-ray pulses from the FEL

    E-Print Network [OSTI]

    Zholents, Alexander A.; Fawley, William M.

    2004-01-01T23:59:59.000Z

    can be used instead of HC FEL. In the following illustra-UM is now tuned for resonant FEL interaction with the 32-nmAttosecond X-Ray Pulses from the FEL Alexander A. Zholents,

  8. X-ray micromodulated luminescence tomography in dual-cone ...

    E-Print Network [OSTI]

    2014-07-01T23:59:59.000Z

    Jul 16, 2014 ... ing the intensity of x-ray energy at the vertex point of a double- cone beam. ... such focusing element, but it is of low efficiency and restricted.

  9. Recent Flash X-Ray Injector Modeling

    SciTech Connect (OSTI)

    Houck, T; Blackfield, D; Burke, J; Chen, Y; Javedani, J; Paul, A C

    2004-11-10T23:59:59.000Z

    The injector of the Flash X-Ray (FXR) accelerator has a significantly larger than expected beam emittance. A computer modeling effort involving three different injector design codes was undertaken to characterize the FXR injector and determine the cause of the large emittance. There were some variations between the codes, but in general the simulations were consistent and pointed towards a much smaller normalized, rms emittance (36 cm-mr) than what was measured (193 cm-mr) at the exit of the injector using a pepperpot technique. The simulations also indicated that the present diode design was robust with respect to perturbations to the nominal design. Easily detected mechanical alignment/position errors and magnet errors did not lead to appreciable increase in the simulated emittance. The physics of electron emission was not modeled by any of the codes and could be the source of increased emittance. The nominal simulation assumed uniform Child-Langmuir Law emission from the velvet cathode and no shroud emission. Simulations that looked at extreme non-uniform cathode and shroud emission scenarios resulted in doubling of the emittance. An alternative approach was to question the pepperpot measurement. Simulations of the measurement showed that the pepperpot aperture foil could double the emittance with respect to the non-disturbed beam. This leads to a diplomatic explanation of the discrepancy between predicted and measured emittance where the fault is shared. The measured value is too high due to the effect of the diagnostic on the beam and the simulations are too low because of unaccounted cathode and/or shroud emission physics. Fortunately there is a relatively simple experiment that can resolve the emittance discrepancy. If the large measured emittance value is correct, the beam envelope is emittance dominated at modest values of focusing field and beam radius. Measurements of the beam envelope on an imaging foil at the exit of the injector would lead to an accurate value of the emittance. If the emittance was approximately half of the measured value, the beam envelope is slightly space charge dominated, but envelope measurements would set reasonable bounds on the emittance value. For an emittance much less than 100 cm-mr, the envelope measurements would be insensitive to emittance. The outcome of this envelope experiment determines if a redesigned diode is needed or if more sophisticated emittance measurements should be pursued.

  10. X-ray tube with magnetic electron steering

    DOE Patents [OSTI]

    Reed, Kim W. (Albuquerque, NM); Turman, Bobby N. (Albuquerque, NM); Kaye, Ronald J. (Albuquerque, NM); Schneider, Larry X. (Albuquerque, NM)

    2000-01-01T23:59:59.000Z

    An X-ray tube uses a magnetic field to steer electrons. The magnetic field urges electrons toward the anode, increasing the proportion of electrons emitted from the cathode that reach desired portions of the anode and consequently contribute to X-ray production. The magnetic field also urges electrons reflected from the anode back to the anode, further increasing the efficiency of the tube.

  11. Quantum coherence phenomena in x-ray optics

    E-Print Network [OSTI]

    Anisimov, Petr Mikhailovich

    2009-05-15T23:59:59.000Z

    QUANTUM COHERENCE PHENOMENA IN X-RAY OPTICS A Dissertation by PETR MIKHAILOVICH ANISIMOV Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY December... 2008 Major Subject: Physics QUANTUM COHERENCE PHENOMENA IN X-RAY OPTICS A Dissertation by PETR MIKHAILOVICH ANISIMOV Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR...

  12. New Directions in X-Ray Light Sources

    ScienceCinema (OSTI)

    Roger Falcone

    2010-01-08T23:59:59.000Z

    July 15, 2008 Berkeley Lab lecture: Molecular movies of chemical reactions and material phase transformations need a strobe of x-rays, the penetrating light that reveals how atoms and molecules assemble in chemical and biological systems and complex materials. Roger Falcone, Director of the Advanced Light Source,will discuss a new generation of x ray sources that will enable a new science of atomic dynamics on ultrafast timescales.

  13. Enhanced betatron X-rays from axially modulated plasma wakefields

    E-Print Network [OSTI]

    Palastro, J P; Gordon, D

    2015-01-01T23:59:59.000Z

    In the cavitation regime of plasma-based accelerators, a population of high-energy electrons tailing the driver can undergo betatron motion. The motion results in X-ray emission, but the brilliance and photon energy are limited by the electrons' initial transverse coordinate. To overcome this, we exploit parametrically unstable betatron motion in a cavitated, axially modulated plasma. Theory and simulations are presented showing that the unstable oscillations increase both the total X-ray energy and average photon energy.

  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. Quiet Sun X-rays as Signature for New Particles

    E-Print Network [OSTI]

    K. Zioutas; K. Dennerl; L. DiLella; D. H. H. Hoffmann; J. Jacoby; Th. Papaevangelou

    2004-03-08T23:59:59.000Z

    We have studied published data from the Yohkoh solar X-ray mission, with the purpose of searching for signals from radiative decays of new, as yet undiscovered massive neutral particles. This search is based on the prediction that solar axions of the Kaluza-Klein type should result in the emission of X-rays from the Sun direction beyond the limb with a characteristic radial distribution. These X-rays should be observed more easily during periods of quiet Sun. An additional signature is the observed emission of hard X-rays by SMM, NEAR and RHESSI. The recent observation made by RHESSI of a continuous emission from the non-flaring Sun of X-rays in the 3 to ~15 keV range fits the generic axion scenario. This work also suggests new analyses of existing data, in order to exclude instrumental effects; it provides the rationale for targeted observations with present and upcoming (solar) X-ray telescopes, which can provide the final answer on the nature of the signals considered here. Such measurements become more promising during the forthcoming solar cycle minimum with an increased number of quiet Sun periods.

  16. Spectral Formation in X-Ray Pulsar Accretion Columns

    E-Print Network [OSTI]

    Peter A. Becker; Michael T. Wolff

    2005-03-03T23:59:59.000Z

    We present the first self-consistent model for the dynamics and the radiative transfer occurring in bright X-ray pulsar accretion columns, with a special focus on the role of the shock in energizing the emerging X-rays. The pressure inside the accretion column of a luminous X-ray pulsar is dominated by the photons, and consequently the equations describing the coupled radiative-dynamical structure must be solved simultaneously. Spectral formation in these sources is therefore a complex, nonlinear phenomenon. We obtain the analytical solution for the Green's function describing the upscattering of monochromatic radiation injected into the column from the thermal mound located near the base of the flow. The Green's function is convolved with a Planck distribution to model the X-ray spectrum resulting from the reprocessing of blackbody photons produced in the thermal mound. These photons diffuse through the infalling gas and eventually escape out the walls of the column, forming the observed X-ray spectrum. We show that the resulting column-integrated, phase-averaged spectrum has a power-law shape at high energies and a blackbody shape at low energies, in agreement with the observational data for many X-ray pulsars.

  17. Characterization of Nano and Mesoscale Deformation Structures with Intense X-ray Synchrotron Sources

    SciTech Connect (OSTI)

    Ice, G.E.; Barabash, R.I.; Walker, F.J. (ORNL)

    2010-07-19T23:59:59.000Z

    Advanced polychromatic microdiffraction is sensitive to the organization of dislocations and other defects that rotate the lattice planes. Using ultra-brilliant third-generation synchrotron sources and non-dispersive X-ray focusing optics, it is now possible to analyze individual dislocation cells and walls at a submicron scale that cannot be probed by traditional methods. The method is applied to an Ir weld sample to illustrate how microdiffraction can be used to determine the locally active dislocation system.

  18. Optimization for Single-Spike X-Ray FELs at LCLS with a Low Charge Beam

    SciTech Connect (OSTI)

    Wang, L.; Ding, Y.; Huang, Z.; /SLAC

    2011-12-14T23:59:59.000Z

    The Linac Coherent Light Source is an x-ray free-electron laser at the SLAC National Accelerator Laboratory, which is operating at x-ray wavelengths of 20-1.2 Angstrom with peak brightness nearly ten orders of magnitude beyond conventional synchrotron radiation sources. At the low charge operation mode (20 pC), the x-ray pulse length can be <10 fs. In this paper we report our numerical optimization and simulations to produce even shorter x-ray pulses by optimizing the machine and undulator setup at 20 pC charge. In the soft x-ray regime, with combination of slotted-foil or undulator taper, a single spike x-ray pulse is achievable with peak FEL power of a few 10s GW. Linac Coherent Light Source (LCLS), the world's first hard x-ray Free electron laser (FEL), has started operation since 2009. With nominal operation charge of 250 pC, the generated x-ray pulse length is from 70 fs to a few hundred fs. This marks the beginning of a new era of ultrashort x-ray sciences. In addition, a low charge (20pC) operation mode has also been established. Since the collective effects are reduced at the low charge mode, we can increase the compression factor and still achieve a few kA peak current. The expected electron beam and x-ray pulses are less than 10 fs. There are growing interests in even shorter x-ray pulses, such as fs to sub-fs regime. One of the simple solutions is going to even lower charge. As discussed, single-spike x-ray pulses can be generated using 1 pC charge. However, this charge level is out of the present LCLS diagnostic range. 20 pC is a reasonable operation charge at LCLS, based on the present diagnostic system. At 20 pC in the soft x-ray wavelength regime, we have experimentally demonstrated that FEL can work at undercompression or over-compression mode, such as 1 degree off the full-compression; at full-compression, however, there is almost no lasing. In hard x-ray wavelength regime, we observed that there are reasonable photons generated even at full-compression mode, although the photon number is less than that from under-compression or over-compression mode. Since we cannot measure the x-ray pulse length at this time scale, the machine is typically optimized for generating maximum photons, not minimum pulse length. In this paper, we study the methods of producing femtosecond (or single-spike) x-ray pulses at LCLS with 20 pC charge, based on start-to-end simulations. Figure 1 shows a layout of LCLS. The compression in the second bunch compressor (BC2) determines the final e-beam bunch length. However, the laser heater, dog-leg after the main linac (DL2) and collective effects also affect the final bunch length. To adjust BC2 compression, we can either change the L2 phase or BC2 R{sub 56}. In this paper we only tune L2 phase while keep BC2 R{sub 56} fixed. For the start-to-end simulations, we used IMPACT-T and ELEGANT tracking from the photocathode to the entrance of the undulator, after that the FEL radiation was simulated with GENESIS. IMPACT-T tracks about 10{sup 6} particles in the injector part until 135 MeV, including 3D space charge force. The output particles from IMPACT-T are smoothed and increased to 12 x 10{sup 6} to reduce high-frequency numerical noise for subsequent ELEGANT simulations, which include linear and nonlinear transport effects, a 1D transient model of CSR, and longitudinal space charge effects, as well as geometric and resistive wake fields in the accelerator. In GENESIS part, the longitudinal wake field from undulator chamber and longitudinal space field are also included.

  19. Variable growth modes of CaF[sub 2] on Si(111) determined by x-ray photoelectron diffraction

    SciTech Connect (OSTI)

    Denlinger, J.D.; Rotenberg, E. (Department of Physics, University of California, Berkeley, California 94720 (United States) Materials Sciences Division, Lawrence Berkeley Laboratory, Berkeley, California 94720 (United States)); Hessinger, U.; Leskovar, M. (Department of Physics FM-15, University of Washington, Seattle, Washington 98195 (United States)); Olmstead, M.A. (Department of Physics FM-15, University of Washington, Seattle, Washington 98195 (United States) Materials Sciences Division, Lawrence Berkeley Laboratory, Berkeley, California 94720 (United States))

    1993-04-26T23:59:59.000Z

    Chemical discrimination of bulk and interface Ca 2[ital p] x-ray photoelectron diffraction modulations is used to identify three growth regimes during the initial stages of CaF[sub 2] epitaxy on Si(111). Low flux, high temperature conditions produce island growth atop a nonwetting, chemically reacted Ca-F interface layer. Changing the growth kinetics by increasing the flux produces more laminar growth. Lowering the substrate temperature produces a more stoichiometric CaF[sub 2] interface layer that results in immediate wetting and laminar growth.

  20. A High Efficiency Grazing Incidence Pumped X-ray Laser

    SciTech Connect (OSTI)

    Dunn, J; Keenan, R; Price, D F; Patel, P K; Smith, R F; Shlyaptsev, V N

    2006-08-31T23:59:59.000Z

    The main objective of the project is to demonstrate a proof-of-principle, new type of high efficiency, short wavelength x-ray laser source that will operate at unprecedented high repetition rates (10Hz) that could be scaled to 1kHz or higher. The development of a high average power, tabletop x-ray laser would serve to complement the wavelength range of 3rd and future 4th generation light sources, e.g. the LCLS, being developed by DOE-Basic Energy Sciences. The latter are large, expensive, central, synchrotron-based facilities while the tabletop x-ray laser is compact, high-power laser-driven, and relatively inexpensive. The demonstration of such a unique, ultra-fast source would allow us to attract funding from DOE-BES, NSF and other agencies to pursue probing of diverse materials undergoing ultrafast changes. Secondly, this capability would have a profound impact on the semiconductor industry since a coherent x-ray laser source would be ideal for ''at wavelength'' {approx}13 nm metrology and microscopy of optics and masks used in EUV lithography. The project has major technical challenges. We will perform grazing-incidence pumped laser-plasma experiments in flat or groove targets which are required to improve the pumping efficiency by ten times. Plasma density characterization using our existing unique picosecond x-ray laser interferometry of laser-irradiated targets is necessary. Simulations of optical laser propagation as well as x-ray laser production and propagation through freely expanding and confined plasma geometries are essential. The research would be conducted using the Physics Directorate Callisto and COMET high power lasers. At the end of the project, we expect to have a high-efficiency x-ray laser scheme operating below 20 nm at 10Hz with a pulse duration of {approx}2 ps. This will represent the state-of-the-art in x-ray lasers and would be a major step forward from our present picosecond laser-driven x-ray lasers. There is an added bonus of creating the shortest wavelength laboratory x-ray laser, below 4.5 nm and operating in the water window, by using the high-energy capability of the Titan laser.

  1. HIgh Rate X-ray Fluorescence Detector

    SciTech Connect (OSTI)

    Grudberg, Peter Matthew [XIA LLC

    2013-04-30T23:59:59.000Z

    The purpose of this project was to develop a compact, modular multi-channel x-ray detector with integrated electronics. This detector, based upon emerging silicon drift detector (SDD) technology, will be capable of high data rate operation superior to the current state of the art offered by high purity germanium (HPGe) detectors, without the need for liquid nitrogen. In addition, by integrating the processing electronics inside the detector housing, the detector performance will be much less affected by the typically noisy electrical environment of a synchrotron hutch, and will also be much more compact than current systems, which can include a detector involving a large LN2 dewar and multiple racks of electronics. The combined detector/processor system is designed to match or exceed the performance and features of currently available detector systems, at a lower cost and with more ease of use due to the small size of the detector. In addition, the detector system is designed to be modular, so a small system might just have one detector module, while a larger system can have many â?? you can start with one detector module, and add more as needs grow and budget allows. The modular nature also serves to simplify repair. In large part, we were successful in achieving our goals. We did develop a very high performance, large area multi-channel SDD detector, packaged with all associated electronics, which is easy to use and requires minimal external support (a simple power supply module and a closed-loop water cooling system). However, we did fall short of some of our stated goals. We had intended to base the detector on modular, large-area detectors from Ketek GmbH in Munich, Germany; however, these were not available in a suitable time frame for this project, so we worked instead with pnDetector GmbH (also located in Munich). They were able to provide a front-end detector module with six 100 m^2 SDD detectors (two monolithic arrays of three elements each) along with associated preamplifiers; these detectors surpassed the performance we expected to get from the Ketek detectors, however they are housed in a sealed module, which does not offer the ease of repair and expandability weâ??d hoped to achieve with the Ketek SDDâ??s. Our packaging efforts were quite successful, as we came up with a very compact way to mount the detector and to house the associated electronics, as well as a very effective way to reliably take out the heat (from the electronics as well as the detectorâ??s Peltier coolers) without risk of condensation and without external airflow or vibration, which could create problems for the target applications. While we were able to design compact processing electronics that fit into the detector assembly, they are still at the prototype stage, and would require a significant redesign to achieve product status. We have not yet tested this detector at a synchrotron facility; we do still plan on working with some close contacts at the nearby Stanford Synchrotron Radiation Laboratory (SSRL) to get some testing with the beam (using existing commercial electronics for readout, as the integrated processor is not ready for use).

  2. Gamma-ray burst flares: X-ray flaring. II

    SciTech Connect (OSTI)

    Swenson, C. A.; Roming, P. W. A., E-mail: cswenson@astro.psu.edu [Pennsylvania State University, 525 Davey Lab, University Park, PA 16802 (United States)

    2014-06-10T23:59:59.000Z

    We present a catalog of 498 flaring periods found in gamma-ray burst (GRB) light curves taken from the online Swift X-Ray Telescope GRB Catalogue. We analyzed 680 individual light curves using a flare detection method developed and used on our UV/optical GRB Flare Catalog. This method makes use of the Bayesian Information Criterion to analyze the residuals of fitted GRB light curves and statistically determines the optimal fit to the light curve residuals in an attempt to identify any additional features. These features, which we classify as flares, are identified by iteratively adding additional 'breaks' to the light curve. We find evidence of flaring in 326 of the analyzed light curves. For those light curves with flares, we find an average number of ?1.5 flares per GRB. As with the UV/optical, flaring in our sample is generally confined to the first 1000 s of the afterglow, but can be detected to beyond 10{sup 5} s. Only ?50% of the detected flares follow the 'classical' definition of ?t/t ? 0.5, with many of the largest flares exceeding this value.

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

    SciTech Connect (OSTI)

    Wang, Yong [Colorado State University, Fort Collins] [Colorado State University, Fort Collins; Wang, Shoujun [Colorado State University, Fort Collins] [Colorado State University, Fort Collins; Oliva, E [Laboratoire de Physique des Gaz et des Gaz et des Plasmas] [Laboratoire de Physique des Gaz et des Gaz et des Plasmas; Lu, L [Laboratoire de Physique des Gaz et des Gaz et des Plasmas] [Laboratoire de Physique des Gaz et des Gaz et des Plasmas; Berrill, Mark A [ORNL] [ORNL; Yin, Liang [Colorado State University, Fort Collins] [Colorado State University, Fort Collins; Nejdl, J [Colorado State University, Fort Collins] [Colorado State University, Fort Collins; Luther, Brad [Colorado State University, Fort Collins] [Colorado State University, Fort Collins; Proux, C [Laboratoire d’Optique Applique´e, ENSTA, CNRS, Ecole Polytechnique] [Laboratoire d’Optique Applique´e, ENSTA, CNRS, Ecole Polytechnique; Le, T. T. [Laboratoire de Physique des Gaz et des Gaz et des Plasmas] [Laboratoire de Physique des Gaz et des Gaz et des Plasmas; Dunn, James [Lawrence Livermore National Laboratory (LLNL)] [Lawrence Livermore National Laboratory (LLNL); Ros, D [Laboratoire de Physique des Gaz et des Gaz et des Plasmas] [Laboratoire de Physique des Gaz et des Gaz et des Plasmas; Zeitoun, Philippe [École Polytechnique] [École Polytechnique; Rocca, Jorge [Colorado State University, Fort Collins] [Colorado State University, Fort Collins

    2014-01-01T23:59:59.000Z

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

  4. Diffraction imaging for in-situ characterization of double-crystal x-ray monochromators

    E-Print Network [OSTI]

    Stoupin, Stanislav; Heald, Steve M; Brewe, Dale; Meron, Mati

    2015-01-01T23:59:59.000Z

    Imaging of the Bragg reflected x-ray beam is proposed and validated as an in-situ method for characterization of performance of double-crystal monochromators under the heat load of intense synchrotron radiation. A sequence of images is collected at different angular positions on the reflectivity curve of the second crystal and analyzed. The method provides rapid evaluation of the wavefront of the exit beam, which relates to local misorientation of the crystal planes along the beam footprint on the thermally distorted first crystal. The measured misorientation can be directly compared to results of finite element analysis. The imaging method offers an additional insight on the local intrinsic crystal quality over the footprint of the incident x-ray beam.

  5. Comparison of methods to quantify interface trap densities at dielectric/IIIV semiconductor interfaces

    E-Print Network [OSTI]

    Stemmer, Susanne

    2010-01-01T23:59:59.000Z

    high-k/III-V interface. 2 Meth- ods to determine the D it ofand capacitance based meth- ods. The dopant concentration

  6. Methods and systems for monitoring a solid-liquid interface

    DOE Patents [OSTI]

    Stoddard, Nathan G. (Gettysburg, PA); Clark, Roger F. (Frederick, MD)

    2011-10-04T23:59:59.000Z

    Methods and systems are provided for monitoring a solid-liquid interface, including providing a vessel configured to contain an at least partially melted material; detecting radiation reflected from a surface of a liquid portion of the at least partially melted material; providing sound energy to the surface; measuring a disturbance on the surface; calculating at least one frequency associated with the disturbance; and determining a thickness of the liquid portion based on the at least one frequency, wherein the thickness is calculated based on L=(2m-1)v.sub.s/4f, where f is the frequency where the disturbance has an amplitude maximum, v.sub.s is the speed of sound in the material, and m is a positive integer (1, 2, 3, . . . ).

  7. Water destruction by X-rays in young stellar objects

    E-Print Network [OSTI]

    P. Stauber; J. K. Jorgensen; E. F. van Dishoeck; S. D. Doty; A. O. Benz

    2006-02-06T23:59:59.000Z

    We study the H2O chemistry in star-forming environments under the influence of a central X-ray source and a central far ultraviolet (FUV) radiation field. The gas-phase water chemistry is modeled as a function of time, hydrogen density and X-ray flux. To cover a wide range of physical environments, densities between n_H = 10^4-10^9 cm^-3 and temperatures between T = 10-1000 K are studied. Three different regimes are found: For T water abundance is of order 10^-7-10^-6 and can be somewhat enhanced or reduced due to X-rays, depending on time and density. For 100 K 10^-3 ergs s-1 cm^-2 (t = 10^4 yrs) and for F_X > 10^-4 ergs s^-1 cm^-2 (t = 10^5 yrs). At higher temperatures (T > 250 K) and hydrogen densities, water can persist with x(H2O) ~ 10^-4 even for high X-ray fluxes. The X-ray and FUV models are applied to envelopes around low-mass Class 0 and I young stellar objects (YSOs). Water is destroyed in both Class 0 and I envelopes on relatively short timescales (t ~ 5000 yrs) for realistic X-ray fluxes, although the effect is less prominent in Class 0 envelopes due to the higher X-ray absorbing densities there. FUV photons from the central source are not effective in destroying water. The average water abundance in Class I sources for L_X > 10^27 ergs s^-1 is predicted to be x(H2O) < 10^-6.

  8. 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.

  9. Novel Approaches to Soft X-ray Spectroscopy: Scanning TransmissionX-ray Microscopy and Ambient Pressure X-Ray PhotoelectronSpectroscopy

    SciTech Connect (OSTI)

    Bluhm, Hendrik; Gilles, Mary K.; Mun, Simon B.; Tyliszczak, Tolek

    2006-02-01T23:59:59.000Z

    This workshop focused on novel spectroscopies at Beamlines 11.0.2, 5.3.2 and 9.3.2 at the ALS. The workshop brought together users from a wide range of fields to highlight recent experimental and technical developments both in scanning transmission X-ray spectroscopy (STXM) and ambient pressure photoelectron spectroscopy (APPES). The morning session featured talks on experiments involving new developments at the STXM, while the afternoon session was devoted to those using APXPS. In the morning session, Tolek Tyliszczak discussed the improved detector developments at the STXM, such as an avalanche photodiode detector and fluorescence and electron detection, as well as the continued development of in situ cells for heating, gas flow, and electrochemical cells. Of these, only the avalanche photodiode in combination with a novel multichannel photon-counting system is in routine use in time-resolved studies. Bartel Van Waeyenberge (Ghent University) presented results of magnetic imaging with a time resolution of 70-100 ps combined with a lateral resolution of 20-40 nm performed with the STXM (Beamline 11.0.2). As a complement to the time-domain ''pump-and-probe'' measurements, they developed a frequency-domain ''sine-excitation'' technique in order to study specific eigenmodes of these ferromagnetic patterns with high spatial resolution. This new approach was used to study the gyrotropic vortex motions in micron-sized ferromagnetic patterns. Adam Hitchcock (McMaster University) presented the development, in collaboration with Daniel Guay (INRS, Varennes) and Sherry Zhang, of the apparatus and techniques for applying STXM to in-situ studies of electrochemistry, in particular electrochromism in polyaniline. In addition, substantial progress was reported on a joint project to develop substrates and methods for chemically selective lithography of multilayer polymer systems. Selective patterns, such as that displayed in the figure, can now be written efficiently with the bend magnet STXM on Beamline 5.3.2. Yves Acremann (SSRL) discussed time and spatially resolved X-ray magnetic circular dichroism (XMCD) experiments on spin transfer devices at the STXM (Beamline 11.0.2). These elegant experiments explore time resolved measurements of the magnetization dynamics within a 100 x 150 nm sample influenced by a spin-polarized current. This experiment shows that the magnetization in these magnetic nanostructures are not uniform, as they are influenced by the Oersted field of the charge current needed to generate the spin current. The implementation of a novel multichannel photon counting system in combination with an avalanche photon detector decreased the data-acquisition time by a factor of 10, owing to its ability to resolve the structure of multi bunch mode. Gordon E. Brown, Jr. (Stanford University and SSRL) described ''Applications of STXM to Microbial Bioweathering and Biomineralization''. In the interaction of bacteria with ferrihydrite nanoparticles, microenvironments that were very different than the bulk material were observed, showing that bulk thermodynamics may not be useful for predicting micro phases. Gordon also presented work showing that iron nanoparticles are attracted to the negatively charged bacteria and form a coating that reduces iron oxide minerals. The afternoon session started with presentations by Simon Mun and Hendrik Bluhm, who discussed the current status and the future plans for the two APPES end-stations at the ALS, which are located at Beamlines 9.3.2 and 11.0.2, respectively. In both end-stations, samples can be measured in gaseous environments at pressures of up to several Torr, which makes possible the investigation of numerous phenomena, in particular in the fields of atmospheric and environmental science as well as heterogeneous catalysis. Specific examples of the application of APPES were shown in the following presentations. John Hemminger (University of California, Irvine) reported on APPES investigations at Beamlines 9.3.2 and 11.0.2 of the interaction of alkali halide surfaces with water. The m

  10. Tools for a Theoretical X-ray Beamline J. J. Rehr*

    E-Print Network [OSTI]

    Botti, Silvana

    Tools for a Theoretical X-ray Beamline J. J. Rehr* Department of Physics University of Washington, France 22 October 2010 #12;X-ray Spectroscopy Beamline #12;Tools for a Theoretical X-ray Beamline · GOAL Theoretical X-ray Beamline: 2. Tools for EXAFS and XANES, EELS, XMCD, ... 3. DFT/MD-TOOLS 4. Next generation

  11. Fourier analysis of X-ray micro-diffraction profiles to characterize laser shock peened metals

    E-Print Network [OSTI]

    Yao, Y. Lawrence

    .L., 1950. The effect of cold-work distortion on X-ray pat- terns. Journal of Applied Physics 21, 595LSP need to be further studied from the measured X-ray micro-diffraction profile. Broadening of X-rayFourier analysis of X-ray micro-diffraction profiles to characterize laser shock peened metals

  12. Quantification of rapid environmental redox processes with quick-scanning x-ray absorption

    E-Print Network [OSTI]

    Sparks, Donald L.

    Quantification of rapid environmental redox processes with quick-scanning x-ray absorption. Here we apply quick-scanning x-ray absorption spectroscopy (Q-XAS), at sub-second time that can be measured using x-ray absorption spectroscopy. arsenic extended x-ray absorption fine structure

  13. Numerical simulations of X-rays Free Electron Lasers (XFEL)

    E-Print Network [OSTI]

    Paolo Antonelli; Agissilaos Athanassoulis; Zhongyi Huang; Peter A. Markowich

    2014-06-17T23:59:59.000Z

    We study a nonlinear Schr\\"odinger equation which arises as an effective single particle model in X-ray Free Electron Lasers (XFEL). This equation appears as a first-principles model for the beam-matter interactions that would take place in an XFEL molecular imaging experiment in \\cite{frat1}. Since XFEL is more powerful by several orders of magnitude than more conventional lasers, the systematic investigation of many of the standard assumptions and approximations has attracted increased attention. In this model the electrons move under a rapidly oscillating electromagnetic field, and the convergence of the problem to an effective time-averaged one is examined. We use an operator splitting pseudo-spectral method to investigate numerically the behaviour of the model versus its time-averaged version in complex situations, namely the energy subcritical/mass supercritical case, and in the presence of a periodic lattice. We find the time averaged model to be an effective approximation, even close to blowup, for fast enough oscillations of the external field. This work extends previous analytical results for simpler cases \\cite{xfel1}.

  14. Delayed Ultrafast X-ray Auger Probing (DUXAP) of Nucleobase Ultraviolet Photoprotection

    E-Print Network [OSTI]

    McFarland, B K; Miyabe, S; Tarantelli, F; Aguilar, A; Berrah, N; Bostedt, C; Bozek, J; Bucksbaum, P H; Castagna, J C; Coffee, R; Cryan, J; Fang, L; Feifel, R; Gaffney, K; Glownia, J; Martinez, T; Mucke, M; Murphy, B; Natan, A; Osipov, T; Petrovic, V; Schorb, S; Schultz, Th; Spector, L; Swiggers, M; Tenney, I; Wang, S; White, W; White, J; Gühr, M

    2013-01-01T23:59:59.000Z

    We present a new method for ultrafast spectroscopy of molecular photoexcited dynamics. The technique uses a pair of femtosecond pulses: a photoexcitation pulse initiating excited state dynamics followed by a soft x-ray (SXR) probe pulse that core ionizes certain atoms inside the molecule. We observe the Auger decay of the core hole as a function of delay between the photoexcitation and SXR pulses. The core hole decay is particularly sensitive to the local valence electrons near the core and shows new types of propensity rules, compared to dipole selection rules in SXR absorption or emission spectroscopy. We apply the delayed ultrafast x-ray Auger probing (DUXAP) method to the specific problem of nucleobase photoprotection to demonstrate its potential. The ultraviolet photoexcited \\pi\\pi* states of nucleobases are prone to chemical reactions with neighboring bases. To avoid this, the single molecules funnel the \\pi\\pi* population to lower lying electronic states on an ultrafast timescale under violation of the...

  15. 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.

  16. Viewing spin structures with soft x-ray microscopy

    SciTech Connect (OSTI)

    Fischer, Peter

    2010-06-01T23:59:59.000Z

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

  17. The History of X-ray Free-Electron Lasers

    SciTech Connect (OSTI)

    Pellegrini, C.; /UCLA /SLAC; ,

    2012-06-28T23:59:59.000Z

    The successful lasing at the SLAC National Accelerator Laboratory of the Linear Coherent Light Source (LCLS), the first X-ray free-electron laser (X-ray FEL), in the wavelength range 1.5 to 15 {angstrom}, pulse duration of 60 to few femtoseconds, number of coherent photons per pulse from 10{sup 13} to 10{sup 11}, is a landmark event in the development of coherent electromagnetic radiation sources. Until now electrons traversing an undulator magnet in a synchrotron radiation storage ring provided the best X-ray sources. The LCLS has set a new standard, with a peak X-ray brightness higher by ten orders of magnitudes and pulse duration shorter by three orders of magnitudes. LCLS opens a new window in the exploration of matter at the atomic and molecular scales of length and time. Taking a motion picture of chemical processes in a few femtoseconds or less, unraveling the structure and dynamics of complex molecular systems, like proteins, are some of the exciting experiments made possible by LCLS and the other X-ray FELs now being built in Europe and Asia. In this paper, we describe the history of the many theoretical, experimental and technological discoveries and innovations, starting from the 1960s and 1970s, leading to the development of LCLS.

  18. ON THE X-RAY OUTBURSTS OF TRANSIENT ANOMALOUS X-RAY PULSARS AND SOFT GAMMA-RAY REPEATERS

    SciTech Connect (OSTI)

    Cal Latin-Small-Letter-Dotless-I skan, Sirin; Ertan, Uenal [Sabanc Latin-Small-Letter-Dotless-I University, Orhanl Latin-Small-Letter-Dotless-I -Tuzla, Istanbul, 34956 (Turkey)

    2012-10-20T23:59:59.000Z

    We show that the X-ray outburst light curves of four transient anomalous X-ray pulsars (AXPs) and soft gamma-ray repeaters (SGRs), namely, XTE J1810-197, SGR 0501+4516, SGR 1627-41, and CXOU J164710.2-455216, can be produced by the fallback disk model that was also applied to the outburst light curves of persistent AXPs and SGRs in our earlier work. The model solves the diffusion equation for the relaxation of a disk that has been pushed back by a soft gamma-ray burst. The sets of main disk parameters used for these transient sources are very similar to each other and to those employed in our earlier models of persistent AXPs and SGRs. There is a characteristic difference between the X-ray outburst light curves of transient and persistent sources. This can be explained by the differences in the disk surface density profiles of the transient and persistent sources in quiescence indicated by their quiescent X-ray luminosities. Our results imply that a viscous disk instability operating at a critical temperature in the range of {approx}1300-2800 K is a common property of all fallback disks around AXPs and SGRs. The effect of the instability is more pronounced and starts earlier for the sources with lower quiescent luminosities, which leads to the observable differences in the X-ray enhancement light curves of transient and persistent sources. A single active disk model with the same basic disk parameters can account for the enhancement phases of both transient and persistent AXPs and SGRs. We also present a detailed parameter study to show the effects of disk parameters on the evolution of the X-ray luminosity of AXPs and SGRs in the X-ray enhancement phases.

  19. Quantized hard-x-ray phase vortices nucleated by aberrated nanolenses

    SciTech Connect (OSTI)

    Pavlov, Konstantin M. [School of Science and Technology, University of New England, Armidale, New South Wales 2351 (Australia); School of Physics, Monash University, Victoria 3800 (Australia); Paganin, David M. [School of Physics, Monash University, Victoria 3800 (Australia); Vine, David J. [ARC Centre of Excellence for Coherent X-ray Science, School of Physics, The University of Melbourne, Parkville, Victoria 3010 (Australia); Schmalz, Jelena A. [School of Science and Technology, University of New England, Armidale, New South Wales 2351 (Australia); Suzuki, Yoshio; Uesugi, Kentaro; Takeuchi, Akihisa; Yagi, Naoto [SPring-8/JASRI (Japan Synchrotron Radiation Research Institute), Hyogo 679-5198 (Japan); Kharchenko, Alexander; Blaj, Gabriel [PANalytical B.V., P.O. Box 13, 7600 AA Almelo (Netherlands); Jakubek, Jan [Institute of Experimental and Applied Physics, Czech Technical University in Prague, 166 36 Prague 6 (Czech Republic); Altissimo, Matteo [Melbourne Centre for Nanofabrication, 151 Wellington Road, Clayton, Victoria 3168 (Australia); Materials Science and Engineering, Commonwealth Scientific and Industrial Research Organisation, Clayton South, Victoria 3169 (Australia); Clark, Jesse N. [London Centre for Nanotechnology, University College, Gower St, London WC1E 6BT (United Kingdom)

    2011-01-15T23:59:59.000Z

    Quantized x-ray phase vortices, namely, screw-type topological defects in the wave fronts of a coherent monochromatic scalar x-ray wave field, may be spontaneously nucleated by x-ray lenses. Phase retrieval is used to reconstruct the phase and amplitude of the complex disturbance created by aberrated gold nanolenses illuminated with hard x rays. A nanoscale quantized x-ray vortex-antivortex dipole is observed, manifest both as a pair of opposite-helicity branch points in the Riemann sheets of the multivalued x-ray phase map of the complex x-ray field and in the vorticity of the associated Poynting vector field.

  20. 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.

  1. Nucleon density in the nuclear periphery determined with antiprotonic x-rays cadmium and tin isotopes

    E-Print Network [OSTI]

    Schmidt, R; Czosnyka, T; Von Egidy, T; Gulda, K; Hartmann, F J; Jastrzebski, J J; Ketzer, B; Kisielinski, M; Klos, B; Kurcewicz, W; Lubinski, P; Napiorkowski, P J; Pienkowski, L; Smolanczuk, R; Widmann, E; Wycech, S

    2003-01-01T23:59:59.000Z

    The x-ray cascade from antiprotonic atoms was studied for 106Cd, 116Cd, 112Sn, 116Sn, 120Sn, and 124Sn. Widths and shifts of the levels due to strong interaction were deduced. Isotopic effects in the Cd and Sn isotopes are clearly seen. The results are used to investigate the nucleon density in the nuclear periphery. The deduced neutron distributions are compared with the results of the previously introduced radiochemical method and with HFB calculations.

  2. Development of in situ, at-wavelength metrology for soft x-ray nano-focusing

    SciTech Connect (OSTI)

    Yuan, Sheng Sam; Yashchuk, Valeriy V.; Goldberg, Kenneth A.; Celestre, Richard; McKinney, Wayne R.; Morrison, Gregory Y.; Warwick, Tony; Padmore, Howard A.

    2010-09-19T23:59:59.000Z

    At the Advanced Light Source (ALS), we are developing broadly applicable, high-accuracy, in situ, at-wavelength wavefront slope measurement techniques for Kirkpatrick-Baez (KB) mirror nano-focusing. We describe here details of the metrology beamline endstation, the at-wavelength tests, and an original alignment method that have already allowed us to precisely set a bendable KB mirror to achieve a FWHM focused spot size of ~;;120 nm, at 1-nm soft x-ray wavelength.

  3. X-Ray Diffraction Study of Elemental Erbium to 65 GPa

    SciTech Connect (OSTI)

    Pravica, M.G.; Lipinska-Kalita, K.; Quine, Z.; Romano, E.; Nicol, M.F. (UNLV)

    2006-02-02T23:59:59.000Z

    We have investigated phase transitions in elemental erbium in a diamond anvil cell up to 65 GPa using x-ray powder diffraction methods. We present preliminary evidence of a series of phase transitions that appear to follow the expected hcp {yields} Sm-type {yields} dhcp {yields} distorted fcc sequence. In particular, we believe that we have evidence for the predicted dhcp {yields} distorted fcc transition between 43 GPa and 65 GPa.

  4. Hard X-rays from Emission Line Galaxies and the X-ray Background: A Test for Advection Dominated Accretion with Radio Sources

    E-Print Network [OSTI]

    Insu Yi; Stephen P. Boughn

    1997-10-14T23:59:59.000Z

    Recent studies of the cosmic X-ray background (XRB) have suggested the possible existence of a population of relatively faint sources with hard X-ray spectra; however, the emission mechanism remains unclear. If the hard X-ray emission is from the radiatively inefficient, advection dominated accretion flows (ADAFs) around massive black holes in galactic nuclei, X-ray luminosity and radio luminosity satisfy the approximate relation $L_R\\sim 7\\times 10^{35}(\

  5. Feasibility Study of Gas Electron Multiplier Detector as an X-Ray Image Sensor

    E-Print Network [OSTI]

    Shin, Sukyoung; Lee, Soonhyouk

    2015-01-01T23:59:59.000Z

    For its ease manufacturing, flexible geometry, and cheap manufacturing cost, the gas electron multiplier (GEM) detector can be used as an x-ray image sensor. For this purpose, we acquired relative detection efficiencies and suggested a method to increase the detection efficiency in order to study the possibility of GEM detector as an x-ray image sensor. The GEM detector system is composed of GEM foils, the instrument system, the gas system, and the negative power supply. The instrument system consists of the A225 charge sensitive preamp, A206 discriminator, and MCA8000D multichannel analyzer. For the gas system, Argon gas was mixed with CO2 to the ratio of 8:2, and for the negative 2,000 volts, the 3106D power supply was used. The CsI-coated GEM foil was used to increase the detection efficiency. Fe-55 was used as an x-ray source and the relative efficiency was acquired by using the ratio of GEM detector to the CdTe detector. The total count method and the energy spectrum method were used to calculate the rel...

  6. Eta Car and Its Surroundings: the X-ray Diagnosis

    E-Print Network [OSTI]

    M. F. Corcoran; K. Hamaguchi

    2007-03-02T23:59:59.000Z

    X-ray emission from the supermassive star Eta Carinae (\\ec) originates from hot shocked gas produced by current stellar mass loss as well as ejecta from prior eruptive events. Absorption of this emission by cool material allows the determination of the spatial and temporal distribution of this material. Emission from the shocked gas can provide important information about abundances through the study of thermal X-ray line emission. We discuss how studies of the X-ray emission from Eta Car at a variety of temporal, spatial and spectral scales and resolutions have helped refine our knowledge of both the continuous and discrete mass loss from the system, and its interactions with more extended material around the star.

  7. Counterparts to the Nuclear Bulge X-ray source population

    E-Print Network [OSTI]

    Andrew J. Gosling; Reba M. Bandyopadhyay; Katherine M. Blundell; Phil Lucas

    2008-06-25T23:59:59.000Z

    We present an initial matching of the source positions of the Chandra Nuclear Bulge X-ray sources to the new UKIDSS-GPS near-infrared survey of the Nuclear Bulge. This task is made difficult by the extremely crowded nature of the region, despite this, we find candidate counterparts to ~50% of the X-ray sources. We show that detection in the J-band for a candidate counterpart to an X-ray source preferentially selects those candidate counterparts in the foreground whereas candidate counterparts with only detections in the H and K-bands are more likely to be Nuclear Bulge sources. We discuss the planned follow-up for these candidate counterparts.

  8. Non-thermal X-ray Emission from Supernova Remnants

    E-Print Network [OSTI]

    Jacco Vink

    2004-09-21T23:59:59.000Z

    Recent studies of narrow, X-ray synchrotron radiating filaments surrounding young supernova remnants indicate that magnetic fields strengths are relatively high, B ~ 0.1 mG, or even higher, and that diffusion is close to the Bohm limit. I illustrate this using Cas A as an example. Also older remnants such as RCW 86 appear to emit X-ray synchrotron radiation, but the emission is more diffuse, and not always confined to a region close to the shock front. I argue that for RCW 86 the magnetic field is likely to be low (B ~ 17 microGauss), and at the location where the shell emits X-ray synchrotron radiation the shock velocity is much higher than the average shock velocity of ~600 km/s.

  9. Movable anode x-ray source with enhanced anode cooling

    DOE Patents [OSTI]

    Bird, C.R.; Rockett, P.D.

    1987-08-04T23:59:59.000Z

    An x-ray source is disclosed having a cathode and a disc-shaped anode with a peripheral surface at constant radius from the anode axis opposed to the cathode. The anode has stub axle sections rotatably carried in heat conducting bearing plates which are mounted by thermoelectric coolers to bellows which normally bias the bearing plates to a retracted position spaced from opposing anode side faces. The bellows cooperate with the x-ray source mounting structure for forming closed passages for heat transport fluid. Flow of such fluid under pressure expands the bellows and brings the bearing plates into heat conducting contact with the anode side faces. A worm gear is mounted on a shaft and engages serrations in the anode periphery for rotating the anode when flow of coolant is terminated between x-ray emission events. 5 figs.

  10. Movable anode x-ray source with enhanced anode cooling

    DOE Patents [OSTI]

    Bird, Charles R. (Ypsilanti, MI); Rockett, Paul D. (Ann Arbor, MI)

    1987-01-01T23:59:59.000Z

    An x-ray source having a cathode and a disc-shaped anode with a peripheral surface at constant radius from the anode axis opposed to the cathode. The anode has stub axle sections rotatably carried in heat conducting bearing plates which are mounted by thermoelectric coolers to bellows which normally bias the bearing plates to a retracted position spaced from opposing anode side faces. The bellows cooperate with the x-ray source mounting structure for forming closed passages for heat transport fluid. Flow of such fluid under pressure expands the bellows and brings the bearing plates into heat conducting contact with the anode side faces. A worm gear is mounted on a shaft and engages serrations in the anode periphery for rotating the anode when flow of coolant is terminated between x-ray emission events.

  11. 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.

  12. Fundamental physics at an X-ray free electron laser

    E-Print Network [OSTI]

    A. Ringwald

    2001-12-19T23:59:59.000Z

    X-ray free electron lasers (FELs) have been proposed to be constructed both at SLAC in the form of the so-called Linac Coherent Light Source as well as at DESY, where the so-called XFEL laboratory is part of the design of the electron-positron linear collider TESLA. In addition to the immediate applications in condensed matter physics, chemistry, material science, and structural biology, X-ray FELs may be employed also to study some physics issues of fundamental nature. In this context, one may mention the boiling of the vacuum (Schwinger pair creation in an external field), horizon physics (Unruh effect), and axion production. We review these X-ray FEL opportunities of fundamental physics and discuss the necessary technological improvements in order to achieve these goals.

  13. 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.

  14. Quiescent X-ray emission from an evolved brown dwarf ?

    E-Print Network [OSTI]

    B. Stelzer

    2004-09-27T23:59:59.000Z

    I report on the X-ray detection of Gl569Bab. During a 25ksec Chandra observation the binary brown dwarf is for the first time spatially separated in X-rays from the flare star primary Gl569A. Companionship to Gl569A constrains the age of the brown dwarf pair to ~300-800 Myr. The observation presented here is only the second X-ray detection of an evolved brown dwarf. About half of the observing time is dominated by a large flare on Gl569Bab, the remainder is characterized by weak and non-variable emission just above the detection limit. This emission -- if not related to the afterglow of the flare -- represents the first detection of a quiescent corona on a brown dwarf, representing an important piece in the puzzle of dynamos in the sub-stellar regime.

  15. 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.

  16. COSMOLOGICAL CONSTRAINTS FROM SUNYAEV-ZEL'DOVICH-SELECTED CLUSTERS WITH X-RAY OBSERVATIONS IN THE FIRST 178 deg[superscript 2] OF THE SOUTH POLE TELESCOPE SURVEY

    E-Print Network [OSTI]

    Andersson, Karl

    We use measurements from the South Pole Telescope (SPT) Sunyaev-Zel'dovich (SZ) cluster survey in combination with X-ray measurements to constrain cosmological parameters. We present a statistical method that fits for the ...

  17. X-ray Absorption Measurements on Nickel Cathode of Sodium-beta Alumina batteries: Fe-Ni-CI Chemical Associations

    SciTech Connect (OSTI)

    Bowden, Mark E.; Alvine, Kyle J.; Fulton, John L.; Lemmon, John P.; Lu, Xiaochuan; Webb-Robertson, Bobbie-Jo M.; Heald, Steve M.; Balasubramanian, Mahalingam; Mortensen, Devon R.; Seidler, Gerald T.; Hess, Nancy J.

    2014-02-01T23:59:59.000Z

    Sections of Na-Al-NiCl2 cathodes from sodium-beta alumina ZEBRA batteries have been characterized with X-ray fluorescence mapping, and XANES measurements to probe the microstructure, elemental correlation, and chemical speciation after voltage cycling. Cycling was performed under identical load conditions at either 240 or 280 °C operating temperature and subsequently quenched in either the charged or discharged state. X-ray fluorescence mapping and XANES measurements were made adjacent to the current collector and ?"-Al2O3 solid electrolyte interfaces to detect possible gradients in chemical properties across the cathode. An FeS additive, introduced during battery synthesis, was found to be present as either Fe metal or an Fe(II) chloride in all cathode samples. X-ray fluorescence mapping reveals an operating temperature and charge-state dependent spatial correlation between Fe, Ni, and Cl concentration. XANES measurements indicate that both Ni and Fe are chemically reactive and shift between metallic and chloride phases in the charged and discharged states, respectively. However the percentage of chemically active Ni and Fe is significantly less in the cell operated at lower temperature. Additionally, the cathode appeared chemically homogeneous at the scale of our X-ray measurements.

  18. Advances in the Detection of As in Environmental Samples Using Low Energy X-ray Fluorescence in a Scanning Transmission X-ray

    E-Print Network [OSTI]

    Hitchcock, Adam P.

    X-ray emission (PIXE),4 or energy dispersive X-ray (EDX) spectrometry in scanning or transmission XAdvances in the Detection of As in Environmental Samples Using Low Energy X-ray Fluorescence at high spatial resolution is needed in many areas of geobiochemistry and environmental science. Scanning

  19. Advances in X-Ray Chemical Analysis, Japan, 45 (2014) ISSN 0911-7806 Report on 10th Chinese X-Ray Spectrometry Conference (CXRSC)

    E-Print Network [OSTI]

    Jun, Kawai

    and Information Technology), Dr. Yidong Zhao (Institute of High Energy Physics of Chinese Academy of Sciences-Ray Spectrometry Conference (CXRSC) Ying LIU #12;#12;45 345 Report on 10th Chinese X-Ray Spectrometry Conference (CXRSC) Adv. X-Ray. Chem. Anal., Japan 45, pp.345-348 (2014) Report on 10th Chinese X-Ray Spectrometry

  20. Probing stellar winds and accretion physics in high-mass X-ray binaries and ultra-luminous X-ray sources with LOFT

    E-Print Network [OSTI]

    Orlandini, M; Zampieri, L; Bozzo, E; Baykal, A; Blay, P; Chernyakova, M; Corbet, R; D'Aì, A; Enoto, T; Ferrigno, C; Finger, M; Klochkov, D; Kreykenbohm, I; Inam, S C; Jenke, P; Masetti, N; Manousakis, A; Mihara, T; Paul, B; Postnov, K; Reig, P; Romano, P; Santangelo, A; Shakura, N; Staubert, R; Torrejón, J M; Walter, R; Wilms, J; Wilson-Hodge, C

    2015-01-01T23:59:59.000Z

    This is a White Paper in support of the mission concept of the Large Observatory for X-ray Timing (LOFT), proposed as a medium-sized ESA mission. We discuss the potential of LOFT for the study of high-mass X-ray binaries and ultra-luminous X-ray sources. For a summary, we refer to the paper.

  1. X-RAY BINARY EVOLUTION ACROSS COSMIC TIME

    SciTech Connect (OSTI)

    Fragos, T.; Zezas, A. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)] [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Lehmer, B.; Tzanavaris, P. [Department of Physics and Astronomy, The Johns Hopkins University, Homewood Campus, Baltimore, MD 21218 (United States)] [Department of Physics and Astronomy, The Johns Hopkins University, Homewood Campus, Baltimore, MD 21218 (United States); Tremmel, M. [Department of Astronomy, University of Washington, Box 351580, U.W., Seattle, WA 98195-1580 (United States)] [Department of Astronomy, University of Washington, Box 351580, U.W., Seattle, WA 98195-1580 (United States); Basu-Zych, A.; Hornschemeier, A.; Jenkins, L.; Ptak, A. [NASA Goddard Space Flight Centre, Code 662, Greenbelt, MD 20771 (United States)] [NASA Goddard Space Flight Centre, Code 662, Greenbelt, MD 20771 (United States); Belczynski, K. [Astronomical Observatory, University of Warsaw, Al. Ujazdowskie 4, 00-478 Warsaw (Poland)] [Astronomical Observatory, University of Warsaw, Al. Ujazdowskie 4, 00-478 Warsaw (Poland); Kalogera, V., E-mail: tfragos@cfa.harvard.edu [Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 (United States)

    2013-02-10T23:59:59.000Z

    High-redshift galaxies permit the study of the formation and evolution of X-ray binary (XRB) populations on cosmological timescales, probing a wide range of metallicities and star formation rates (SFRs). In this paper, we present results from a large-scale population synthesis study that models the XRB populations from the first galaxies of the universe until today. We use as input to our modeling the Millennium II cosmological simulation and the updated semi-analytic galaxy catalog by Guo et al. to self-consistently account for the star formation history and metallicity evolution of the universe. Our modeling, which is constrained by the observed X-ray properties of local galaxies, gives predictions about the global scaling of emission from XRB populations with properties such as SFR and stellar mass, and the evolution of these relations with redshift. Our simulations show that the X-ray luminosity density (X-ray luminosity per unit volume) from XRBs in our universe today is dominated by low-mass XRBs, and it is only at z {approx}> 2.5 that high-mass XRBs become dominant. We also find that there is a delay of {approx}1.1 Gyr between the peak of X-ray emissivity from low-mass XRBs (at z {approx} 2.1) and the peak of SFR density (at z {approx} 3.1). The peak of the X-ray luminosity from high-mass XRBs (at z {approx} 3.9) happens {approx}0.8 Gyr before the peak of the SFR density, which is due to the metallicity evolution of the universe.

  2. X Ray Precursors in SGRs: Precessing Gamma Jet Tails

    E-Print Network [OSTI]

    Daniele Fargion

    2001-05-18T23:59:59.000Z

    Weak isolated X-ray precursor events before the main Gamma Ray Burst, GRB, and also rare Soft Gamma Repeaters, SGR, events are in complete disagreement with any Fireball, or Magnetar, one-shoot explosive scenarios. Fireball model in last two years has been deeply modified into a fountain beamed Jet exploding and interacting on external shells to explain GRB fine time structure. On the contrary earlier we proposed a unified scenario for both GRBs-SGRs where a precessing Gamma Jet (of different intensity) and its geometrical beaming is the source of both GRB and SGRs wide morphology. GRBs are peaked SNs Jet spinning and precessing observed along the thin Jet axis. Their mysterious weak X precursors bursts, corresponding to non-negligible energy powers, up to million Supernova ones for GRB, are gamma Jet tails beamed off-axis, observed at X-Ray tails. They are rare, about (3-6)% of all GRBs, but not unique at all. Comparable brief X-ray precursor flashes occurred in rarest and most detailed SGRs events as the 27 and the 29 August 1998 event from SGR 1900+14. The same source has been in very power-full activity on recent 18 April 2001 once again preceded by X-Ray precursors. These events are inconsistent with any Fireball or Magnetar-Mini-Fireball models. We interpret them naturally as earlier marginal blazing of outlying X conical precessing Jet, an off-axis tails surrounding a narrower gamma precessing Jet. Only when the light-house Jet is in on-axis blazing mode toward the Earth we observe the harder power-full SGR event. We predict such a rich X-Ray precursor signals (more numerous then gamma ones) during Soft Gamma Repeater peak activities; they should be abundant and within detection threshold by a permanent monitoring SGRs by Beppo-Sax WFC or Chandra X ray satellites while at peak activity.

  3. Bragg x-ray survey spectrometer for ITER

    SciTech Connect (OSTI)

    Varshney, S. K.; Jakhar, S. [ITER-India, Institute for Plasma Research, Bhat, Gandhinagar, Gujarat 382428 (India); Barnsley, R. [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul Lez Durance (France); O'Mullane, M. G. [Department of Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom)

    2012-10-15T23:59:59.000Z

    Several potential impurity ions in the ITER plasmas will lead to loss of confined energy through line and continuum emission. For real time monitoring of impurities, a seven channel Bragg x-ray spectrometer (XRCS survey) is considered. This paper presents design and analysis of the spectrometer, including x-ray tracing by the Shadow-XOP code, sensitivity calculations for reference H-mode plasma and neutronics assessment. The XRCS survey performance analysis shows that the ITER measurement requirements of impurity monitoring in 10 ms integration time at the minimum levels for low-Z to high-Z impurity ions can largely be met.

  4. The NIF x-ray spectrometer calibration campaign at Omega

    SciTech Connect (OSTI)

    Pérez, F.; Kemp, G. E.; Barrios, M. A.; Pino, J.; Scott, H.; Ayers, S.; Chen, H.; Emig, J.; Colvin, J. D.; Fournier, K. B., E-mail: fournier2@llnl.gov [Lawrence Livermore National Laboratory, P. O. Box 808, Livermore, California 94551 (United States); Regan, S. P.; Bedzyk, M.; Shoup, M. J.; Agliata, A.; Yaakobi, B.; Marshall, F. J.; Hamilton, R. A. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States); Jaquez, J.; Farrell, M.; Nikroo, A. [General Atomics, P.O. Box 85608, San Diego, California 92186 (United States)

    2014-11-15T23:59:59.000Z

    The calibration campaign of the National Ignition Facility X-ray Spectrometer (NXS) was carried out at the OMEGA laser facility. Spherically symmetric, laser-driven, millimeter-scale x-ray sources of K-shell and L-shell emission from various mid-Z elements were designed for the 2–18 keV energy range of the NXS. The absolute spectral brightness was measured by two calibrated spectrometers. We compare the measured performance of the target design to radiation hydrodynamics simulations.

  5. X-Ray Binary Systems in the Small Magellanic Cloud

    E-Print Network [OSTI]

    P. Kahabka; W. Pietsch

    1997-06-09T23:59:59.000Z

    We present the result of a systematic search for spectrally hard and soft X-ray binary systems in the Small Magellanic Cloud (SMC). This search has been applied to ROSAT PSPC data (0.1-2.4 keV) collected during 9 pointed observations towards this galaxy covering a time span of 2 years from October 91 till October 93. Selection criteria have been defined in order to confine the sample of candidates. Finally 7 spectrally hard and 4 spectrally soft sources were selected from the list as candidates for binaries in the SMC. The sample is luminosity limited (>3.10**35 erg/s). SMC X-1 has been observed during a full binary orbit starting with a low-state covering an X-ray eclipse and emerging into a bright long-duration flare with two short-duration flares separated by 10 hours. The Be type transient SMC X-2 has been redetected with ROSAT. Variability has been found in the sources RX J0051.8-7231 and RX J0052.1-731 already discovered with Einstein. RX J0101.0-7206 has been discovered at the north-eastern boundary of the giant SMC HII region N66 during an X-ray outburst and half a year later during a quiescent phase. A variable source, RX J0049.1-7250, located north-east of the SMC supernova remnant N19 and which may either be an X-ray binary or an AGN turns out to be strongly absorbed. It may be located behind the SMC. If it is an X-ray binary then it radiates at the Eddington limit in the X-ray bright state. Another variable and hard X-ray source RX J0032.9-7348 has been discovered at the south-eastern border of the body of the SMC. A high mass X-ray binary nature is favored for this source. We searched for CAL87 like systems in the SMC catalog and found none. A new candidate supersoft source RX J0103.8-7254 has been detected. We cannot exclude that it is a foreground object.

  6. The dominant X-ray wind in massive star binaries

    E-Print Network [OSTI]

    J. M. Pittard; I. R. Stevens

    2002-04-15T23:59:59.000Z

    We investigate which shocked wind is responsible for the majority of the X-ray emission in colliding wind binaries, an issue where there is some confusion in the literature, and which we show is more complicated than has been assumed. We find that where both winds rapidly cool (typically close binaries), the ratio of the wind speeds is often more important than the momentum ratio, because it controls the energy flux ratio, and the faster wind is generally the dominant emitter. When both winds are largely adiabatic (typically long-period binaries), the slower and denser wind will cool faster and the stronger wind generally dominates the X-ray luminosity.

  7. The First Angstrom X-Ray Free-Electron Laser

    SciTech Connect (OSTI)

    Galayda, John; /SLAC

    2012-08-24T23:59:59.000Z

    The Linac Coherent Light Source produced its first x-ray laser beam on 10 April 2009. Today it is routinely producing x-ray pulses with energy >2 mJ across the operating range from 820-8,200 eV. The facility has begun operating for atomic/molecular/optical science experiments. Performance of the facility in its first user run (1 October - 21 December) and current machine development activities will be presented. Early results from the preparations for the start of the second user run is also reported.

  8. Viscosity in X-ray clusters: Braginskii over 5

    E-Print Network [OSTI]

    A. Gruzinov

    2006-11-07T23:59:59.000Z

    We argue that it is currently impossible to simulate X-ray clusters using correct equations, because even the MHD description is not applicable. But since fluid simulations actually reproduce observations quite well, one may try to improve the fluid codes by including molecular transport of heat and momentum. We calculate the effective molecular viscosity for the simplest model of magnetic field and obtain 1/5 of the Braginskii value, similar to 1/3 of Spitzer for the heat conduction. This is large enough to noticeably damp the X-ray cluster turbulence.

  9. Confusion of Diffuse Objects in the X-ray Sky

    E-Print Network [OSTI]

    G. Mark Voit; August E. Evrard; Greg L. Bryan

    2000-12-08T23:59:59.000Z

    Most of the baryons in the present-day universe are thought to reside in intergalactic space at temperatures of 10^5-10^7 K. X-ray emission from these baryons contributes a modest (~10%) fraction of the ~ 1 keV background whose prominence within the large-scale cosmic web depends on the amount of non-gravitational energy injected into intergalactic space by supernovae and AGNs. Here we show that the virialized regions of groups and clusters cover over a third of the sky, creating a source-confusion problem that may hinder X-ray searches for individual intercluster filaments and contaminate observations of distant groups.

  10. 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...

  11. High-resolution radio observations of X-ray binaries

    E-Print Network [OSTI]

    James Miller-Jones

    2008-09-15T23:59:59.000Z

    I present an overview of important results obtained using high-resolution very long baseline interferometry (VLBI) observations of X-ray binary systems. These results derive from both astrometric observations and resolved imaging of sources, from black holes to neutron star and even white dwarf systems. I outline a number of upcoming developments in instrumentation, both new facilities and ongoing upgrades to existing VLBI instruments, and I conclude by identifying a number of important areas of investigation where VLBI will be crucial in advancing our understanding of X-ray binaries.

  12. Femtosecond Time-Delay X-ray Holography

    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 Power AdministrationField8,Dist. CategoryFebruaryFebruary 17,Time-Delay X-ray Holography X-ray

  13. V444 Cyg X-ray and polarimetric variability: Radiative and Coriolis forces shape the wind collision region

    E-Print Network [OSTI]

    Lomax, Jamie R; Hoffman, Jennifer L; Russell, Christopher M P; De Becker, Michael; Corcoran, Michael F; Davidson, James W; Neilson, Hilding R; Owocki, Stan; Pittard, Julian M; Pollock, Andy M T

    2014-01-01T23:59:59.000Z

    We present results from a study of the eclipsing, colliding-wind binary V444 Cyg that uses a combination of X-ray and optical spectropolarimetric methods to describe the 3-D nature of the shock and wind structure within the system. We have created the most complete X-ray light curve of V444 Cyg to date using 40 ksec of new data from Swift, and 200 ksec of new and archived XMM-Newton observations. In addition, we have characterized the intrinsic, polarimetric phase-dependent behavior of the strongest optical emission lines using data obtained with the University of Wisconsin's Half-Wave Spectropolarimeter. We have detected evidence of the Coriolis distortion of the wind-wind collision in the X-ray regime, which manifests itself through asymmetric behavior around the eclipses in the system's X-ray light curves. The large opening angle of the X-ray emitting region, as well as its location (i.e. the WN wind does not collide with the O star, but rather its wind) are evidence of radiative braking/inhibition occurri...

  14. The determination of Os and Ir by delayed X-ray spectrometry

    SciTech Connect (OSTI)

    Pillay, A.E.; Mashilo, N. (Univ. of Witwatersrand (South Africa))

    1990-01-01T23:59:59.000Z

    Delayed X-ray spectrometry preceded by fast neutron activation, is a relatively novel application and its capabilities as an analytical tool for the specific determination of Os and Ir in small powdered samples was evaluated. The investigation took the form of a feasibility study which relied heavily on the high sensitivity of the detector used. Detection of the delayed X-rays was achieved with a 100 mm{sup 2} Ge detector whose ability to produce optimum photopeak-to-noise ratios formed the basis exploited in this investigation. Analytical conditions are demonstrated over a range of concentrations for the elements of interest and the potential of the technique for application to the general routine analysis of Os and Ir is discussed. The authors indicate that interferences from the sample matrix can be suppressed to a degree which makes the method almost independent of the matrix. This and other attractive features make the technique a strong rival to conventional activation analysis.

  15. 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.

  16. Development of Nanofluidic Cells for Ultrafast X-ray Studies of Water

    SciTech Connect (OSTI)

    Irizarry, Melvin E.; /Puerto Rico U., Mayaguez /SLAC

    2006-08-23T23:59:59.000Z

    In order to study the molecular structure and dynamics of liquid water with soft x-ray probes, samples with nanoscale dimensions are needed. This paper describes a simple method for preparing nanofluidic water cells. The idea is to confine a thin layer of water between two silicon nitride windows. The windows are 1 mm x 1 mm and 0.5 mm x 0.5 mm in size and have a thickness of 150 nm. The thickness of the water layer was measured experimentally by probing the infrared spectrum of water in the cells with a Fourier Transform InfraRed (FTIR) apparatus and from soft x-ray static measurements at the Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory. Water layers ranging from 10 nm to more than 2 {micro}m were observed. Evidence for changes in the water structure compared to bulk water is observed in the ultrathin cells.

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

    SciTech Connect (OSTI)

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

    1993-06-01T23:59:59.000Z

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

  18. Measuring the x-ray resolving power of bent potassium acid phthalate diffraction crystals

    SciTech Connect (OSTI)

    Haugh, M. J., E-mail: haughmj@nv.doe.gov; Jacoby, K. D. [National Security Technologies, LLC, Livermore, California 94550 (United States); Wu, M.; Loisel, G. P. [Sandia National Laboratories, Albuquerque, New Mexico 87123 (United States)

    2014-11-15T23:59:59.000Z

    This report presents the results from measuring the X-ray resolving power of a curved potassium acid phthalate (KAP(001)) spectrometer crystal using two independent methods. It is part of a continuing effort to measure the fundamental diffraction properties of bent crystals that are used to study various characteristics of high temperature plasmas. Bent crystals like KAP(001) do not usually have the same diffraction properties as corresponding flat crystals. Models that do exist to calculate the effect of bending the crystal on the diffraction properties have simplifying assumptions and their accuracy limits have not been adequately determined. The type of crystals that we measured is being used in a spectrometer on the Z machine at Sandia National Laboratories in Albuquerque, New Mexico. The first technique for measuring the crystal resolving power measures the X-ray spectral line width of the characteristic lines from several metal anodes. The second method uses a diode X-ray source and a double crystal diffractometer arrangement to measure the reflectivity curve of the KAP(001) crystal. The width of that curve is inversely proportional to the crystal resolving power. The measurement results are analyzed and discussed.

  19. Crosscheck of different techniques for two dimensional power spectral density measurements of x-ray optics

    SciTech Connect (OSTI)

    Yashchuk, Valeriy V.; Irick, Steve C.; Gullikson, Eric M.; Howells, Malcolm R.; MacDowell, Alastair A.; McKinney, Wayne R.; Salmassi, Farhad; Warwick, Tony

    2005-07-12T23:59:59.000Z

    The consistency of different instruments and methods for measuring two-dimensional (2D) power spectral density (PSD) distributions are investigated. The instruments are an interferometric microscope, an atomic force microscope (AFM) and the X-ray Reflectivity and Scattering experimental facility, all available at Lawrence Berkeley National Laboratory. The measurements were performed with a gold-coated mirror with a highly polished stainless steel substrate. It was shown that these three techniques provide essentially consistent results. For the stainless steel mirror, an envelope over all measured PSD distributions can be described with an inverse power-law PSD function. It is also shown that the measurements can be corrected for the specific spatial frequency dependent systematic errors of the instruments. The AFM and the X-ray scattering measurements were used to determine the modulation transfer function of the interferometric microscope. The corresponding correction procedure is discussed in detail. Lower frequency investigation of the 2D PSD distribution was also performed with a long trace profiler and a ZYGO GPI interferometer. These measurements are in some contradiction, suggesting that the reliability of the measurements has to be confirmed with additional investigation. Based on the crosscheck of the performance of all used methods, we discuss the ways for improving the 2D PSD characterization of X-ray optics.

  20. Comparison of low-energy x-ray and cobalt-60 irradiations of MOS devices as a function of gate bias

    SciTech Connect (OSTI)

    Shaneyfelt, M.R.; Fleetwood, D.M.; Schwank, J.R. (Sandia National Labs., Albuquerque, NM (USA)); Hughes, K.L. (L and M Technologies, Inc., Albuquerque, NM (USA))

    1991-01-01T23:59:59.000Z

    The E{sup {minus}{1/2}} electric field dependence of the saturated density of interface traps in MOS devices is used to improve estimates of charge yield during {sup 60}Co irradiations. Previous discrepancies between 10-keV x-ray and {sup 60}Co response are resolved. 14 refs., 7 figs.

  1. Monte Carlo study for optimal conditions in single-shot imaging with femtosecond x-ray laser pulses

    SciTech Connect (OSTI)

    Park, Jaehyun; Ishikawa, Tetsuya; Song, Changyong [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan)] [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Joti, Yasumasa [Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5198 (Japan)] [Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5198 (Japan)

    2013-12-23T23:59:59.000Z

    Intense x-ray pulses from x-ray free electron lasers (XFELs) enable the unveiling of atomic structure in material and biological specimens via ultrafast single-shot exposures. As the radiation is intense enough to destroy the sample, a new sample must be provided for each x-ray pulse. These single-particle delivery schemes require careful optimization, though systematic study to find such optimal conditions is still lacking. We have investigated two major single-particle delivery methods: particle injection as flying objects and membrane-mount as fixed targets. The optimal experimental parameters were searched for via Monte Carlo simulations to discover that the maximum single-particle hit rate achievable is close to 40%.

  2. Integrated X-ray testing of the electro-optical breadboard model for the XMM reflection grating spectrometer

    SciTech Connect (OSTI)

    Bixler, J.V.; Craig, W.; Decker, T. [Lawrence Livermore National Lab., CA (United States); Aarts, H.; Boggende, T. den; Brinkman, A.C. [Space Research Organization Netherlands, Utrecht (Netherlands); Burkert, W.; Brauninger, H. [Max-Planck Institute fur Extraterrestische Physik, Testanlage (Germany); Branduardi-Raymont, G. [Univ. College London (United Kingdom); Dubbeldam, L. [Space Research Organization Netherlands, Leiden (Netherlands)] [and others

    1994-07-12T23:59:59.000Z

    X-ray calibration of the Electro-Optical Breadboard Model (EOBB) of the XXM Reflection Grating Spectrometer has been carried out at the Panter test facility in Germany. The EOBB prototype optics consisted of a four-shell grazing incidence mirror module followed by an array of eight reflection gratings. The dispersed x-rays were detected by an array of three CCDs. Line profile and efficiency measurements where made at several energies, orders, and geometric configurations for individual gratings and for the grating array as a whole. The x-ray measurements verified that the grating mounting method would meet the stringent tolerances necessary for the flight instrument. Post EOBB metrology of the individual gratings and their mountings confirmed the precision of the grating boxes fabrication. Examination of the individual grating surface`s at micron resolution revealed the cause of anomalously wide line profiles to be scattering due to the crazing of the replica`s surface.

  3. Correlated long-term optical and X-ray variations in NGC 5548

    E-Print Network [OSTI]

    Phil Uttley; Rick Edelson; Ian McHardy; Bradley M. Peterson; Alex Markowitz

    2003-01-13T23:59:59.000Z

    We combine the long-term optical light curve of the Seyfert 1 galaxy NGC5548 with the X-ray light curve measured by the Rossi X-ray Timing Explorer over 6 years, to determine the relationship between the optical and X-ray continua. The X-ray light curve is strongly correlated with the optical light curve on long (~year) time-scales. The amplitude of the long-term optical variability in NGC5548 is larger than that of the X-ray variability (after accounting for the host galaxy contribution), implying that X-ray reprocessing is not the main source of the optical/X-ray correlation. The correlated X-ray and optical variations in NGC5548 may be caused by instabilities in the inner part of the accretion flow, where both the X-ray and optical emission regions may be located.

  4. A mirror for lab-based quasi-monochromatic parallel x-rays

    SciTech Connect (OSTI)

    Nguyen, Thanhhai; Lu, Xun; Lee, Chang Jun; Jeon, Insu, E-mail: i-jeon@chonnam.ac.kr [School of Mechanical Engineering, Chonnam National University, 300 Yongbong-dong, Buk-gu, Gwangju 500-757 (Korea, Republic of); Jung, Jin-Ho [Pro-optics Co., Ltd., 475 Ami-ri, Bubal-eup, Icheon 467-866 (Korea, Republic of); Jin, Gye-Hwan [Department of Radiology, Nambu University, 76 Chumdan Jungang 1-ro, Gwangsan-gu, Gwangju 506-706 (Korea, Republic of); Kim, Sung Youb [School of Mechanical and Advanced Materials Engineering, Ulsan National Institute of Science and Technology, 100 Banyeon-ri, Eonyang-eup, Ulju-gun, Ulsan 689-798 (Korea, Republic of)

    2014-09-15T23:59:59.000Z

    A multilayered parabolic mirror with six W/Al bilayers was designed and fabricated to generate monochromatic parallel x-rays using a lab-based x-ray source. Using this mirror, curved bright bands were obtained in x-ray images as reflected x-rays. The parallelism of the reflected x-rays was investigated using the shape of the bands. The intensity and monochromatic characteristics of the reflected x-rays were evaluated through measurements of the x-ray spectra in the band. High intensity, nearly monochromatic, and parallel x-rays, which can be used for high resolution x-ray microscopes and local radiation therapy systems, were obtained.

  5. Thermal X-ray composites as an effect of projection

    E-Print Network [OSTI]

    O. Petruk

    2001-03-21T23:59:59.000Z

    A new possibility to explain the nature of thermal X-ray composites (TXCs), i.e. a class of supernova remnants (SNRs) with a thermal X-ray centrally-filled morphology within a radio shell, as a projection effect of the 2- or 3-dimensional shell-like SNR evolved in a nonuniform medium with scale-height <10 pc is proposed. Both X-ray and radio morphologies, as well as the basic theoretical features of this kind of SNR and the surrounding medium, are considered. Theoretical properties of a shell-like SNR evolved at the edge of a molecular cloud correspond to the observed properties of TXCs if the gradient of the ambient density does not lie in the projection plane and the magnetic field is nearly aligned with the line of sight. So, at least a part of objects from the class may be interpreted within the framework of the considered effect. The proposed model suggests that SNRs with barrel-like radio and centrally-brightened thermal X-ray morphologies should exist. The model allows us to consider TXCs as prospective sources of proton origin gamma-rays.

  6. Multidimensional analysis of X-ray variability of AGN

    E-Print Network [OSTI]

    A. V. Halevin

    2004-09-07T23:59:59.000Z

    In this work we analyzed X-ray light curves of active galactic nucleus NGC 4051 obtained using Advanced CCD Imaging Spectrometer of Chandra satellite. Taking into account mainly flaring behaviour of AGNs we have used wavelet analysis for searching of short time lived events on light curves.

  7. Quantum coherence phenomena in x-ray optics 

    E-Print Network [OSTI]

    Anisimov, Petr Mikhailovich

    2009-05-15T23:59:59.000Z

    effects in a three-level coherently driven system. Second, we show that the interference effects may appear in X-ray radiation at the nuclear transitions under the condition of the nuclear level anti-crossing. This effects are similar...

  8. Thermal management of masks for deep x-ray lithography.

    SciTech Connect (OSTI)

    Khounsary, A.; Chojnowski, D.; Mancini, D.C.; Lai, B.; Dejus, R.

    1997-11-18T23:59:59.000Z

    This paper addresses some options and techniques in the thermal management of masks used in deep x-ray lithography. The x-ray masks are thin plates made of low-atomic-number materials on which a patterned thin film of a high-atomic-number metal has been deposited. When they are exposed to an x-ray beam, part of the radiation is transmitted to replicate the pattern on a downstream photoresist, and the remainder is absorbed in the mask in the form of heat. This heat load can cause deformation of the mask and thus image distortion in the lithography process. The mask geometry considered in the present study is 100 mm x 100 mm in area, and about 0.1 to 2 mm thick. The incident radiation is a bending magnet x-ray beam having a footprint of 60 mm x 4 mm at the mask. The mask is scanned vertically about {+-} 30 mm so that a 60 mm x 60 mm area is exposed. the maximum absorbed heat load in the mask is 80 W, which is significantly greater than a few watts encountered in previous systems. In this paper, cooling techniques, substrate material selection, transient and steady state thermal and structural behavior, and other thermo-mechanical aspects of mask design are discussed. It is shown that, while diamond and graphite remain attractive candidates, at present beryllium is a more suitable material for this purpose and, when properly cooled, can provide the necessary dimensional tolerance.

  9. DEDUCING ELECTRON PROPERTIES FROM HARD X-RAY OBSERVATIONS

    E-Print Network [OSTI]

    Piana, Michele

    of the accelerated electron distribution. Keywords: Sun: flares; Sun: X-rays; Sun: acceleration; Sun: energetic distribution 31 4.5 Low-energy cutoffs in the electron distribution 32 4.6 Temperature distribution of thermal-ray emission process(es) in question with the electron distribution function, which is in turn a function

  10. X-Ray Astronomy to Resonant Theranostics for Cancer Treatment

    E-Print Network [OSTI]

    Nahar, Sultana Nurun

    of Astronomy, The Ohio State University, Columbus, OH 43210, USA E-mail: nahar@astronomy.ohio. The falling particles spiral around the black hole, move faster close to it and release energy in the form jets at the center (Observed by X-ray space observatory Chandra). In the image: red indicates low-energy

  11. X-ray Emission from Thunderstorms and Lightning

    ScienceCinema (OSTI)

    Joseph Dwyer

    2010-01-08T23:59:59.000Z

    How lightning is initiated in the relatively low electric fields inside thunderclouds and how it can then propagate for tens of kilometers through virgin air are two of the great unsolved problems in the atmospheric sciences.  Until very recently it was believed that lightning was entirely a conventional discharge, involving only low-energy (a few eV) electrons.  This picture changed completely a few years ago with the discovery of intense x-ray emission from both natural cloud-to-ground lightning and rocket-triggered lightning.  This energetic emission cannot be produced by a conventional discharge, and so the presence of x-rays strongly implies that runaway breakdown plays a role in lightning processes.  During runaway breakdown, electrons are accelerated through air to nearly the speed of light by strong electric fields.  These runaway electrons then emit bremsstrahlung x-rays and gamma-rays during collisions with air.  Indeed, the x-ray and gamma-ray emission produced by runaway breakdown near the tops of thunderstorms is bright enough to be seen from outer space, 600 km away.  As a result, the physics used for decades to describe thunderstorm electrification and lightning discharges is incomplete and needs to be revisited. 

  12. Helium and Iron in X-ray galaxy clusters

    E-Print Network [OSTI]

    Stefano Ettori

    2006-10-16T23:59:59.000Z

    I discuss the role of the sedimentation of helium in galaxy cluster cores on the observed X-ray properties and present a history of the metal accumulation in the ICM, with new calculations with respect to my previous work following the recent evidence of a bi-modal distribution of the delay time in Supernovae Type Ia.

  13. In-situ mechanical testing during X-ray diffraction

    SciTech Connect (OSTI)

    Van Swygenhoven, Helena, E-mail: helena.vanswygenhoven@psi.ch; Van Petegem, Steven

    2013-04-15T23:59:59.000Z

    Deforming metals during recording X-ray diffraction patterns is a useful tool to get a deeper understanding of the coupling between microstructure and mechanical behaviour. With the advances in flux, detector speed and focussing techniques at synchrotron facilities, in-situ mechanical testing is now possible during powder diffraction and Laue diffraction. The basic principle is explained together with illustrative examples.

  14. Soft x-ray laser microscope. Final report

    SciTech Connect (OSTI)

    Suckewer, P.I.

    1990-10-01T23:59:59.000Z

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

  15. Vanadium-pumped titanium x-ray laser

    DOE Patents [OSTI]

    Nilsen, J.

    1992-05-26T23:59:59.000Z

    A resonantly photo-pumped x-ray laser is formed of a vanadium and titanium foil combination that is driven by two beams of intense line focused optical laser radiation. Ground state neon-like titanium ions are resonantly photo-pumped by line emission from fluorine-like vanadium ions. 4 figs.

  16. Soft x-ray diagnostics for pulsed power machines

    SciTech Connect (OSTI)

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

    1995-08-01T23:59:59.000Z

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

  17. Compact X-ray Light Source Workshop Report

    SciTech Connect (OSTI)

    Thevuthasan, Suntharampillai; Evans, James E.; Terminello, Louis J.; Koppenaal, David W.; Manke, Kristin L.; Plata, Charity

    2012-12-01T23:59:59.000Z

    This report, produced jointly by EMSL and FCSD, is the result of a workshop held in September 2011 that examined the utility of a compact x-ray light source (CXLS) in addressing many scientific challenges critical to advancing energy science and technology.

  18. Transient x-ray absorption spectroscopy of hydrated halogen atom

    E-Print Network [OSTI]

    Elles, Christopher G.; Shkrob, Ilya A.; Crowell, Robert A.; Arms, Dohn A.; Landahl, Eric C.

    2008-02-11T23:59:59.000Z

    Time-resolved x-ray absorption spectroscopy has been used to observe the transient species generated by one-photon detachment of an electron from aqueous bromide. The K-edge spectrum of the short-lived Br(0) atom exhibits a resonant 1s-4p transition...

  19. Computed tomographic x-ray velocimetry (CTXV)

    E-Print Network [OSTI]

    Albrecht, David

    and regional detection of abnormal lung function. In some cases the detection of pathology was visualised much medical imaging modalities n 100x lower radiation dose than an average CT scan n Offers early, accurate and regional detection of diseases in vital organs prior to detection via conventional invasive methods n

  20. Ultra-Short Electron Bunch and X-Ray Temporal Diagnostics with an X-Band Transverse Deflector

    SciTech Connect (OSTI)

    Ding, Y.; Emma, P.; Frisch, J.; Huang, Z.; Loos, H.; Krejcik, P.; Wang, M-H.; /SLAC; Behrens, C.; /DESY

    2011-12-13T23:59:59.000Z

    The measurement of ultra-short electron bunches on the femtosecond time scale constitutes a very challenging problem. In X-ray free-electron laser facilities such as the Linac Coherent Light Source (LCLS), generation of sub-ten femtosecond X-ray pulses is possible, and some efforts have been put into both ultra-short electron and X-ray beam diagnostics. Here we propose a single-shot method using a transverse rf deflector (X-band) after the undulator to reconstruct both the electron bunch and X-ray temporal profiles. Simulation studies show that about 1 fs (rms) time resolution may be achievable in the LCLS and is applicable to a wide range of FEL wavelengths and pulse lengths. The jitter, resolution and other related issues will be discussed. The successful operation of the Linac Coherent Light Source (LCLS), with its capability of generating free-electron laser (FEL) X-ray pulses from a few femtoseconds (fs) up to a few hundred fs, opens up vast opportunities for studying atoms and molecules on this unprecedented ultrashort time scale. However, tremendous challenges remain in the measurement and control of these ultrashort pulses with femtosecond precision, for both the electron beam (e-beam) and the X-ray pulses. For ultrashort e-beam bunch length measurements, a standard method has been established at LCLS using an S-band radio-frequency (rf) deflector, which works like a streak camera for electrons and is capable of resolving bunch lengths as short as {approx} 10 fs rms. However, the e-beam with low charges of 20 pC at LCLS, which is expected to be less than 10 fs in duration, is too short to be measured using this transverse deflector. The measurement of the electron bunch length is helpful in estimating the FEL X-ray pulse duration. However, for a realistic beam, such as that with a Gaussian shape or even a spiky profile, the FEL amplification varies along the bunch due to peak current or emittance variation. This will cause differences between the temporal shape or duration of the electron bunch and the X-ray pulse. Initial experiments at LCLS have revealed that characterization of the X-ray pulse duration on a shot-by-shot basis is critical for the interpretation of the data. However, a reliable x-ray pulse temporal diagnostic tool is not available so far at the LCLS. We propose a novel method in this paper to characterize the FEL X-ray pulse duration and shape. A transverse rf deflector is used in conjunction with an e-beam energy spectrometer, located after the FEL undulator. By measuring the difference in the e-beam longitudinal phase space between FEL-on and FEL-off, we can obtain the time-resolved energy loss and energy spread induced from the FEL radiation, allowing the FEL X-ray temporal shape to be reconstructed.

  1. 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.

  2. 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.

  3. X-ray ablation measurements and modeling for ICF applications

    SciTech Connect (OSTI)

    Anderson, A.T.

    1996-09-01T23:59:59.000Z

    X-ray ablation of material from the first wall and other components of an ICF (Inertial Confinement Fusion) chamber is a major threat to the laser final optics. Material condensing on these optics after a shot may cause damage with subsequent laser shots. To ensure the successful operation of the ICF facility, removal rates must be predicted accurately. The goal for this dissertation is to develop an experimentally validated x-ray response model, with particular application to the National Ignition Facility (NIF). Accurate knowledge of the x-ray and debris emissions from ICF targets is a critical first step in the process of predicting the performance of the target chamber system. A number of 1-D numerical simulations of NIF targets have been run to characterize target output in terms of energy, angular distribution, spectrum, and pulse shape. Scaling of output characteristics with variations of both target yield and hohlraum wall thickness are also described. Experiments have been conducted at the Nova laser on the effects of relevant x-ray fluences on various materials. The response was diagnosed using post-shot examinations of the surfaces with scanning electron microscope and atomic force microscope instruments. Judgments were made about the dominant removal mechanisms for each material. Measurements of removal depths were made to provide data for the modeling. The finite difference ablation code developed here (ABLATOR) combines the thermomechanical response of materials to x-rays with models of various removal mechanisms. The former aspect refers to energy deposition in such small characteristic depths ({approx} micron) that thermal conduction and hydrodynamic motion are significant effects on the nanosecond time scale. The material removal models use the resulting time histories of temperature and pressure-profiles, along with ancillary local conditions, to predict rates of surface vaporization and the onset of conditions that would lead to spallation.

  4. Soft X-ray spectral variability of AM Herculis

    E-Print Network [OSTI]

    K. Beuermann; E. El Kholy; K. Reinsch

    2008-02-19T23:59:59.000Z

    Polars (AM Herculis binaries) are a prominent class of bright soft X-ray sources, many of which were discovered with ROSAT. We present a homogenous analysis of all the pointed ROSAT PSPC observations of polars subdivided into two papers that discuss the prototype polar AM Her in detail and summarize the class properties of all other polars. We derive the high-state soft X-ray flux and short-term spectral variability of AM Her using a new detector response matrix and a confirmed flux calibration of the ROSAT PSPC below 0.28 keV. The best-fit mean single-blackbody temperature and integrated bright-phase energy flux of AM Her in its April 1991 high state are 27.2 +/- 1.0 eV and (2.6 +/- 0.6) x 10^-9 erg cm^-2s^-1, respectively. The total blackbody flux of a multi-temperature model that fits both the soft X-ray and the fluctuating far-ultraviolet components is Fbb = (4.5 +/- 1.5) x 10^-9 erg cm^-2s^-1. The total accretion luminosity at a distance of 80 pc, Lbb = (2.1 +/- 0.7) x 10^33 erg s-1, implies an accretion rate of Mdot = (2.4 +/- 0.8) x 10^-10 Msun yr^-1 for an 0.78 Msun white dwarf. The soft X-ray flux displays significant variability on time scales down to 200 ms. Correlated spectral and count-rate variations are seen in flares on time scales down to 1 s, demonstrating the heating and cooling associated with individual accretion events. Our spectral and temporal analysis provides direct evidence for the blobby accretion model and suggests a connection between the soft X-ray and the fluctuating far-ultraviolet components.

  5. SUPERLUMINOUS X-RAYS FROM A SUPERLUMINOUS SUPERNOVA

    SciTech Connect (OSTI)

    Levan, A. J.; Wheatley, P. J. [Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom); Read, A. M.; Tanvir, N. R. [Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom); Metzger, B. D., E-mail: a.j.levan@warwick.ac.uk [Department of Physics, Columbia University, 538 West 120th Street, 704 Pupin Hall, MC 5255, New York, NY 10027 (United States)

    2013-07-10T23:59:59.000Z

    The discovery of a population of superluminous supernovae (SLSNe), with peak luminosities a factor of {approx}100 brighter than normal supernovae (SNe; typically SLSNe have M{sub V} < -21), has shown an unexpected diversity in core-collapse SN properties. Numerous models have been postulated for the nature of these events, including a strong interaction of the shockwave with a dense circumstellar environment, a re-energizing of the outflow via a central engine, or an origin in the catastrophic destruction of the star following a loss of pressure due to pair production in an extremely massive stellar core (so-called pair instability SNe). Here we consider constraints that can be placed on the explosion mechanism of hydrogen-poor SLSNe (SLSNe-I) via X-ray observations, with XMM-Newton, Chandra, and Swift, and show that at least one SLSN-I is likely the brightest X-ray SN ever observed, with L{sub X} {approx} 10{sup 45} erg s{sup -1}, {approx}150 days after its initial discovery. This is a luminosity three orders of magnitude higher than seen in other X-ray SNe powered via circumstellar interactions. Such high X-ray luminosities are sufficient to ionize the ejecta and markedly reduce the optical depth, making it possible to see deep into the ejecta and any source of emission that resides there. Alternatively, an engine could have powered a moderately relativistic jet external to the ejecta, similar to those seen in gamma-ray bursts. If the detection of X-rays does require an engine it implies that these SNe do create compact objects, and that the stars are not completely destroyed in a pair instability event. Future observations will determine which, if any, of these mechanisms are at play in SLSNe.

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

    SciTech Connect (OSTI)

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

    2012-03-13T23:59:59.000Z

    Quantification of synchrotron XRF analyses is typically done through comparisons with measurements on the NIST SRM 1832/1833 thin film standards. Unfortunately, these standards are inhomogeneous on small scales at the tens of percent level. We are synthesizing new homogeneous multilayer standards using the Atomic Layer Deposition technique and characterizing them using multiple analytical methods, including ellipsometry, Rutherford Back Scattering at Evans Analytical, Synchrotron X-ray Fluorescence (SXRF) at Advanced Photon Source (APS) Beamline 13-ID, Synchrotron X-ray Absorption Spectroscopy (XAS) at Advanced Light Source (ALS) Beamlines 11.0.2 and 5.3.2.1 and by electron microscopy techniques. Our motivation for developing much-needed cross-calibration of synchrotron techniques is borne from coordinated analyses of particles captured in the aerogel of the NASA Stardust Interstellar Dust Collector (SIDC). The Stardust Interstellar Dust Preliminary Examination (ISPE) team have characterized three sub-nanogram, {approx}1{micro}m-sized fragments considered as candidates to be the first contemporary interstellar dust ever collected, based on their chemistries and trajectories. The candidates were analyzed in small wedges of aerogel in which they were extracted from the larger collector, using high sensitivity, high spatial resolution >3 keV synchrotron x-ray fluorescence spectroscopy (SXRF) and <2 keV synchrotron x-ray transmission microscopy (STXM) during Stardust ISPE. The ISPE synchrotron techniques have complementary capabilities. Hard X-ray SXRF is sensitive to sub-fg mass of elements Z {ge} 20 (calcium) and has a spatial resolution as low as 90nm. X-ray Diffraction data were collected simultaneously with SXRF data. Soft X-ray STXM at ALS beamline 11.0.2 can detect fg-mass of most elements, including cosmochemically important oxygen, magnesium, aluminum and silicon, which are invisible to SXRF in this application. ALS beamline 11.0.2 has spatial resolution better than 25 nm. Limiting factors for Stardust STXM analyses were self-imposed limits of photon dose due to radiation damage concerns, and significant attenuation of <1500 eV X-rays by {approx}80{micro}m thick, {approx}25 mg/cm{sup 3} density silica aerogel capture medium. In practice, the ISPE team characterized the major, light elements using STXM (O, Mg, Al, Si) and the heavier minor and trace elements using SXRF. The two data sets overlapped only with minor Fe and Ni ({approx}1% mass abundance), providing few quantitative cross-checks. New improved standards for cross calibration are essential for consortium-based analyses of Stardust interstellar and cometary particles, IDPs. Indeed, they have far reaching application across the whole synchrotron-based analytical community. We have synthesized three ALD multilayers simultaneously on silicon nitride membranes and silicon and characterized them using RBS (on Si), XRF (on Si{sub 3}N{sub 4}) and STXM/XAS (holey Si{sub 3}N{sub 4}). The systems we have started to work with are Al-Zn-Fe and Y-Mg-Er. We have found these ALD multi-layers to be uniform at {micro}m- to nm scales, and have found excellent consistency between four analytical techniques so far. The ALD films can also be used as a standard for e-beam instruments, eg., TEM EELS or EDX. After some early issues with the consistency of coatings to the back-side of the membrane windows, we are confident to be able to show multi-analytical agreement to within 10%. As the precision improves, we can use the new standards to verify or improve the tabulated cross-sections.

  7. X-ray absorption spectroscopy by full-field X-ray microscopy of a thin graphite flake: Imaging and

    E-Print Network [OSTI]

    Hitchcock, Adam P.

    .bittencourt@ua.ac.be * Corresponding author Keywords: carbon; graphene; nanostructure; NEXAFS; X-ray microscopy Beilstein J structure of graphite flakes consisting of a few graphene layers. The flake was produced by exfoli- ation of the remarkable transport properties of graphene in 2004 by Geim and Novoselov triggered intense interest in its

  8. X-ray source system at the MSFC x-ray calibration facility J. J. Kolodziejczak, R. A. Austin

    E-Print Network [OSTI]

    Wargelin, Bradford J.

    hyperbolic shells, which combine to form AXAF's Wolter-I High-resolution mirror assembly (HRMA), is a phase. A part of this time will be devoted exclusively to x-ray characterization of the HRMA using a set of instruments developed by personnel at the Smithsonian Astrophysical Observatory (SAO) called the HRMA X

  9. 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.

  10. 2256 IEEE TRANSACTIONS ON NUCLEAR SCIENCE, VOL. 47, NO. 6, DECEMBER 2000 Characterization of X-Ray Radiation Damage

    E-Print Network [OSTI]

    Tolk, Norman H.

    optical methods. I. INTRODUCTION PRESENTLY, characterization of traps due to radiation damage in Si-Ray Radiation Damage in Si/SiO2 Structures Using Second-Harmonic Generation Z. Marka, S. K. Singh, W. Wang, S. C-harmonic generation (SHG) measurements for the characterization of X-ray radiation damage in Si/SiO2 structures

  11. 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.

  12. Fiber optics interface for a dye laser oscillator and method

    DOE Patents [OSTI]

    Johnson, Steve A. (Tracy, CA); Seppala, Lynn G. (Pleasanton, CA)

    1986-01-01T23:59:59.000Z

    A dye laser oscillator in which one light beam is used to pump a continuous tream of dye within a cooperating dye chamber for producing a second, different beam is generally disclosed herein along with a specific arrangement including an optical fiber and a fiber optics interface for directing the pumping beam into the dye chamber. The specific fiber optics interface illustrated includes three cooperating lenses which together image one particular dimension of the pumping beam into the dye chamber from the output end of the optical fiber in order to insure that the dye chamber is properly illuminated by the pumping beam.

  13. Fiber optics interface for a dye laser oscillator and method

    DOE Patents [OSTI]

    Johnson, S.A.; Seppala, L.G.

    1984-06-13T23:59:59.000Z

    A dye laser oscillator in which one light beam is used to pump a continuous stream of dye within a cooperating dye chamber for producing a second, different beam is generally disclosed herein along with a specific arrangement including an optical fiber and a fiber optics interface for directing the pumping beam into the dye chamber. The specific fiber optics interface illustrated includes three cooperating lenses which together image one particular dimension of the pumping beam into the dye chamber from the output end of the optical fiber in order to insure that the dye chamber is properly illuminated by the pumping beam.

  14. Beam damage of poly(vinyl chloride) [PVC] as observed by x-ray...

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

    damage of poly(vinyl chloride) PVC as observed by x-ray photoelectron spectroscopy at 143 K, 303 K and 373 K. Beam damage of poly(vinyl chloride) PVC as observed by x-ray...

  15. Non-Destructive X-ray Measurement of Soot, Ash, Washcoat and...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    X-ray Measurement of Soot, Ash, Washcoat and Regeneration Damage for DPFs Non-Destructive X-ray Measurement of Soot, Ash, Washcoat and Regeneration Damage for DPFs New commercially...

  16. The ALS X-Ray Streak Camera: Bringing the Ultrafast and Ultrasmall...

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

    ultrafast is at the frontier of scientific research. Two x-ray approaches can be used for ultrafast examinations. The first entails developing sources that have short x-ray pulses...

  17. Development of procedures for refurbishing x-ray optics at the Advanced Light Source

    E-Print Network [OSTI]

    Yashchuk, Valeriy V.

    2013-01-01T23:59:59.000Z

    and Setting of Bendable Optics for Diffraction- Limitedof Soft X-Rays,” Abstract to SPIE Optics and Photonics 2012,Metrology for X-Ray and EUV Optics IV (San Diego, August 12-

  18. alpha particle x-ray: Topics by E-print Network

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

    of X-rays from the Sun direction beyond the limb with a characteristic radial distribution. These X-rays should be observed more easily during periods of quiet Sun. An...

  19. A New Analysis of X-Ray Adsorption Branching Ratios: Use ofRussell...

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

    Analysis of X-Ray Adsorption Branching Ratios: Use of Russell-Saunders Coupling . A New Analysis of X-Ray Adsorption Branching Ratios: Use of Russell-Saunders Coupling . Abstract:...

  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