National Library of Energy BETA

Sample records for x-ray method shows

  1. X-Ray Nanoimaging: Instruments and Methods

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

    X-Ray Nanoimaging: Instruments and Methods X-Ray Nanoimaging: Instruments and Methods Print To be held as part of SPIE. http://spie.org/OP318 August 28-29, 2013; San Diego, California, USA

  2. X-Ray Nanoimaging: Instruments and Methods

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

    X-Ray Nanoimaging: Instruments and Methods To be held as part of SPIE. http://spie.org/OP318 August 28-29, 2013; San Diego, California, USA

  3. X-Ray Nanoimaging: Instruments and Methods

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

    X-Ray Nanoimaging: Instruments and Methods To be held as part of SPIE. http:spie.orgOP318 August 28-29, 2013; San Diego, California, USA

  4. Holographic Methods in X-ray Crystallography

    Energy Science and Technology Software Center (OSTI)

    1995-07-28

    The holographic method makes use of partially modeled electron density and experimentally-measured structure factor amplitudes to recover electron density corresponding to the unmodeled part of a crystal structure. This paper describes a fast algorithm that makes it possible to apply the holographic method to sizable crystallographic problems. The algorithm uses positivity constraints on the electron density, and can incorporate a target electron density, making it similar to solvent flattening. Using both synthetic and experimental data,more » we assess the potential for applying the holographic method to macromolecular x-ray crystallography.« less

  5. Gamma and X-ray Dosimetric Method

    DOE Patents [OSTI]

    Taplin, G.V.; Douglas, C.H.

    1954-06-29

    This patent application concerns a highly stable two-phase liquid system for use in a colorimetric dosimeter for measuring X-ray and gamma radiation.

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

    DOE Patents [OSTI]

    London, Richard A.; Rosen, Mordecai D.; Strauss, Moshe

    1992-01-01

    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.

  7. Systems and methods for detecting x-rays

    DOE Patents [OSTI]

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

    2006-05-02

    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.

  8. X-ray mask and method for making

    DOE Patents [OSTI]

    Morales, Alfredo M.

    2004-10-26

    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.

  9. Reflection soft X-ray microscope and method

    DOE Patents [OSTI]

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

    1993-01-05

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

  10. Reflection soft X-ray microscope and method

    DOE Patents [OSTI]

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

    1993-01-01

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

  11. X-ray focal spot locating apparatus and method

    DOE Patents [OSTI]

    Gilbert, Hubert W.

    1985-07-30

    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.

  12. X-ray mask and method for providing same

    DOE Patents [OSTI]

    Morales, Alfredo M. (Pleasanton, CA); Skala, Dawn M. (Fremont, CA)

    2004-09-28

    The present invention describes a method for fabricating an x-ray mask tool which can achieve pattern features having lateral dimension of less than 1 micron. The process uses a thin photoresist and a standard lithographic mask to transfer an trace image pattern in the surface of a silicon wafer by exposing and developing the resist. The exposed portion of the silicon substrate is then anisotropically etched to provide an etched image of the trace image pattern consisting of a series of channels in the silicon having a high depth-to-width aspect ratio. These channels are then filled by depositing a metal such as gold to provide an inverse image of the trace image and thereby providing a robust x-ray mask tool.

  13. X-ray mask and method for providing same

    DOE Patents [OSTI]

    Morales, Alfredo M.; Skala, Dawn M.

    2002-01-01

    The present invention describes a method for fabricating an x-ray mask tool which can achieve pattern features having lateral dimension of less than 1 micron. The process uses a thin photoresist and a standard lithographic mask to transfer an trace image pattern in the surface of a silicon wafer by exposing and developing the resist. The exposed portion of the silicon substrate is then anisotropically etched to provide an etched image of the trace image pattern consisting of a series of channels in the silicon having a high depth-to-width aspect ratio. These channels are then filled by depositing a metal such as gold to provide an inverse image of the trace image and thereby providing a robust x-ray mask tool.

  14. Application of hard X-ray microprobe methods to clay-rich materials...

    Office of Scientific and Technical Information (OSTI)

    Application of hard X-ray microprobe methods to clay-rich materials Citation Details In-Document Search Title: Application of hard X-ray microprobe methods to clay-rich materials ...

  15. Advances in Computational Methods for X-Ray Optics III (Conference...

    Office of Scientific and Technical Information (OSTI)

    Conference: Advances in Computational Methods for X-Ray Optics III Citation Details In-Document Search Title: Advances in Computational Methods for X-Ray Optics III Authors: ...

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

    DOE Patents [OSTI]

    Augustoni, Arnold L.; Gerardo, James B.; Raymond, Thomas D.

    1992-01-01

    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.

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

    DOE Patents [OSTI]

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

    1992-12-29

    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.

  18. CHESS X-rays show how to grow crystals from crystals > EMC2 News...

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

    done one at the time. Wide-angle X-ray scattering is used for relatively smaller-scale characterization, revealing information on how atomic planes within individual...

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

    DOE Patents [OSTI]

    Siddons, David Peter; Johnson, Erik D.; Guckel, Henry; Klein, Jonathan L.

    1997-10-21

    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.

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

    DOE Patents [OSTI]

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

    1997-10-21

    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.

  1. Flow method and apparatus for screening chemicals using micro x-ray fluorescence

    DOE Patents [OSTI]

    Warner, Benjamin P.; Havrilla, George J.; Miller, Thomasin C.; Lewis, Cris; Mahan, Cynthia A.; Wells, Cyndi A.

    2011-04-26

    Method and apparatus for screening chemicals using micro x-ray fluorescence. A method for screening a mixture of potential pharmaceutical chemicals for binding to at least one target binder involves flow separating a solution of chemicals and target binders into separated components, exposing them to an x-ray excitation beam, detecting x-ray fluorescence signals from the components, and determining from the signals whether or not a binding event between a chemical and target binder has occurred.

  2. Flow method and apparatus for screening chemicals using micro x-ray fluorescence

    DOE Patents [OSTI]

    Warner, Benjamin P.; Havrilla, George J.; Miller, Thomasin C.; Lewis, Cris; Mahan, Cynthia A.; Wells, Cyndi A.

    2009-04-14

    Method and apparatus for screening chemicals using micro x-ray fluorescence. A method for screening a mixture of potential pharmaceutical chemicals for binding to at least one target binder involves flow-separating a solution of chemicals and target binders into separated components, exposing them to an x-ray excitation beam, detecting x-ray fluorescence signals from the components, and determining from the signals whether or not a binding event between a chemical and target binder has occurred.

  3. The x-ray time of flight method for investigation of ghosting in amorphous selenium-based flat panel medical x-ray imagers

    SciTech Connect (OSTI)

    Rau, A.W.; Bakueva, L.; Rowlands, J.A.

    2005-10-15

    Amorphous selenium (a-Se) based real-time flat-panel imagers (FPIs) are finding their way into the digital radiology department because they offer the practical advantages of digital x-ray imaging combined with an image quality that equals or outperforms that of conventional systems. The temporal imaging characteristics of FPIs can be affected by ghosting (i.e., radiation-induced changes of sensitivity) when the dose to the detector is high (e.g., portal imaging and mammography) or the images are acquired at a high frame rate (e.g., fluoroscopy). In this paper, the x-ray time-of-flight (TOF) method is introduced as a tool for the investigation of ghosting in a-Se photoconductor layers. The method consists of irradiating layers of a-Se with short x-ray pulses. From the current generated in the a-Se layer, ghosting is quantified and the ghosting parameters (charge carrier generation rate and carrier lifetimes and mobilities) are assessed. The x-ray TOF method is novel in that (1) x-ray sensitivity (S) and ghosting parameters can be measured simultaneously (2) the transport of both holes and electrons can be isolated, and (3) the method is applicable to the practical a-Se layer structure with blocking contacts used in FPIs. The x-ray TOF method was applied to an analysis of ghosting in a-Se photoconductor layers under portal imaging conditions, i.e., 1 mm thick a-Se layers, biased at 5 V/{mu}m, were irradiated using a 6 MV LINAC x-ray beam to a total dose (ghosting dose) of 30 Gy. The initial sensitivity (S{sub 0}) of the a-Se layers was 63{+-}2 nC cm{sup -2} cGy{sup -1}. It was found that S decreases to 30% of S{sub 0} after a ghosting dose of 5 Gy and to 21% after 30 Gy at which point no further change in S occurs. At an x-ray intensity of 22 Gy/s (instantaneous dose rate during a LINAC x-ray pulse), the charge carrier generation rate was 1.25{+-}0.1x10{sup 22} ehp m{sup -3} s{sup -1} and, to a first approximation, independent of the ghosting dose. However, both

  4. X-ray microtomography shows pore structure and tortuosity in alkali-activated binders

    SciTech Connect (OSTI)

    Provis, John L.; Myers, Rupert J.; White, Claire E.; Rose, Volker; Deventer, Jannie S.J. van

    2012-06-15

    Durability of alkali-activated binders is of vital importance in their commercial application, and depends strongly on microstructure and pore network characteristics. X-ray microtomography ({mu}CT) offers, for the first time, direct insight into microstructural and pore structure characteristics in three dimensions. Here, {mu}CT is performed on a set of sodium metasilicate-activated fly ash/slag blends, using a synchrotron beamline instrument. Segmentation of the samples into pore and solid regions is then conducted, and pore tortuosity is calculated by a random walker method. Segmented porosity and diffusion tortuosity are correlated, and vary as a function of slag content (slag addition reduces porosity and increases tortuosity), and sample age (extended curing gives lower porosity and higher tortuosity). This is particularly notable for samples with {>=} 50% slag content, where a space-filling calcium (alumino)silicate hydrate gel provides porosity reductions which are not observed for the sodium aluminosilicate ('geopolymer') gels which do not chemically bind water of hydration.

  5. 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

    2013-05-15

    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.

  6. GAMMA AND X-RAY DOSIMETER AND DOSIMETRIC METHOD

    DOE Patents [OSTI]

    Taplin, G.V.; Douglas, C.H.; Sigoloff, S.C.

    1958-08-19

    An improvement in colorimetric gamma and x-ray dosimeter systems and a self-contained. hand carried dostmeter of the afore-mentioned type ts described. A novel point of the invention ltes in the addition of specific quantities of certain normalizing agents to the two phase chlorinated hydro-carbon-aqueous dyc colortmetric dosimeter to eliminate the after reaction and thereby extend the utility of such systein. The structure of the two phase colorimetric dosimeter tubes and the carrying case for the tubes of the portable dosimeter are unique features.

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

    DOE Patents [OSTI]

    Barbee, Jr., Troy W.; Lane, Stephen M.; Hoffman, Donald E.

    2001-01-01

    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.

  8. New X-ray method allows scientists to probe molecular explosions...

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

    New X-ray method allows scientists to probe molecular explosions By Jared Sagoff * June ... However, these aren't new releases from Hollywood studios; they're one type of new ...

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

    DOE Patents [OSTI]

    Warner, Benjamin P.; Havrilla, George J.; Mann, Grace

    2010-12-28

    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.

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

    DOE Patents [OSTI]

    MacGowan, Brian J.; Matthews, Dennis L.; Trebes, James E.

    1988-01-01

    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).

  11. 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.

    1987-05-05

    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.

  12. Measurement of piezoelectric constants of lanthanum-gallium tantalate crystal by X-ray diffraction methods

    SciTech Connect (OSTI)

    Blagov, A. E.; Marchenkov, N. V. Pisarevsky, Yu. V.; Prosekov, P. A.; Kovalchuk, M. V.

    2013-01-15

    A method for measuring piezoelectric constants of crystals of intermediate systems by X-ray quasi-multiple-wave diffraction is proposed and implemented. This technique makes it possible to determine the piezoelectric coefficient by measuring variations in the lattice parameter under an external electric field. This method has been approved, its potential is evaluated, and a comparison with high-resolution X-ray diffraction data is performed.

  13. An Improved X-ray Diffraction Method For Cellulose Crystallinity Measurement

    SciTech Connect (OSTI)

    Ju, Xiaohui; Bowden, Mark E.; Brown, Elvie E.; Zhang, Xiao

    2015-06-01

    We show in this work a modified X-ray diffraction method to determine cellulose crystallinity index (CrI). Nanocrystalline cellulose (NCC) dervided from bleached wood pulp was used as a model substrate. Rietveld refinement was applied with consideration of March-Dollase preferred orientation at the (001) plane. In contrast to most previous methods, three distinct amorphous peaks identified from new model samples which are used to calculate CrI. A 2 theta range from 10° to 75° was found to be more suitable to determine CrI and crystallite structural parameters such as d-spacing and crystallite size. This method enables a more reliable measurement of CrI of cellulose and may be applicable to other types of cellulose polymorphs.

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

    SciTech Connect (OSTI)

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

    2007-08-08

    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.

  15. Multilayer graphene stacks grown by different methods-thickness measurements by X-ray diffraction, Raman spectroscopy and optical transmission

    SciTech Connect (OSTI)

    Tokarczyk, M. Kowalski, G.; Kępa, H.; Grodecki, K.; Drabińska, A.; Strupiński, W.

    2013-12-15

    X-ray diffraction, Raman spectroscopy and Optical absorption estimates of the thickness of graphene multi layer stacks (number of graphene layers) are presented for three different growth techniques. The objective of this work was focused on comparison and reconciliation of the two already widely used methods for thickness estimates (Raman and Absorption) with the calibration of the X-ray method as far as Scherer constant K is concerned and X-ray based Wagner-Aqua extrapolation method.

  16. X-ray survival characteristics and genetic analysis for nine saccharomyces deletion mutants that show altered radiation sensitivity

    SciTech Connect (OSTI)

    Game, John C.; Williamson, Marsha S.; Baccari, Clelia

    2004-01-07

    The availability of a genome-wide set of Saccharomyces deletion mutants provides a chance to identify all the yeast genes involved in DNA repair. Using X-rays, we are screening these mutants to identify additional genes that show increased sensitivity to the lethal effects of ionizing radiation. For each mutant identified as sensitive, we are confirming that the sensitivity phenotype co-segregates with the deletion allele and are obtaining multipoint survival-versus-dose assays in at least two haploid and one homozygous diploid strains. We present data for deletion mutants involving the genes DOT1, MDM20, NAT3, SPT7, SPT20, GCN5, HFI1, DCC1 and VID21/EAF1, and discuss their potential roles in repair. Eight of these genes have a clear radiation-sensitive phenotype when deleted, but the ninth, GCN5, has at most a borderline phenotype. None of the deletions confer substantial sensitivity to ultra-violet radiation, although one or two may confer marginal sensitivity. The DOT1 gene is of interest because its only known function is to methylate one lysine residue in the core of the histone H3 protein. We find that histone H3 mutants (supplied by K. Struhl) in which this residue is replaced by other amino-acids are also X-ray sensitive, seeming to confirm that methylation of the lysine-79 residue is required for effective repair of radiation damage.

  17. X-ray absorption and resonant inelastic x-ray scattering (RIXS) show the presence of Cr{sup +} at the surface and in the bulk of CrF{sub 2}

    SciTech Connect (OSTI)

    Jiménez-Mier, J.; Olalde-Velasco, P.; Yang, W.-L.; Denlinger, J.

    2015-07-23

    X-Ray absorption and resonant inelastic x-ray scattering (RIXS) spectra of CrF{sub 2} recorded at the chromium L{sub 2,3} are presented. An atomic multiplet crystal field calculation is compared with the experimental data. Experiment and theory are in agreement once the calculation includes three chromium oxidation states, namely Cr{sup +}, Cr{sup 2+}, and Cr{sup 3+}. X-Ray absorption allows a direct determination of the surface oxidation, while the RIXS spectra shows the presence of these three oxidation states in the sample bulk. To give a quantitative interpretation of the RIXS data the effect of the incomming and outgoing photon penetration depth and self-absorption must be considered. For the much simpler case of MnF{sub 2}, with only one metal oxidation state, the measured RIXS spectra relative intensities are found to be proportional to the square of the sample attenuation length.

  18. X-Ray Diagnostics

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

    X-Ray Diagnostics X-Ray Diagnostics Maintenance of existing devices and development of advanced concepts Contact John Oertel (505) 665-3246 Email Hot, dense matter produced by intense laser interaction with a solid target often produces x-rays with energies from 100 eV to those exceeding 100 keV. A suite of diagnostics and methods have been deployed at Trident to diagnose the x-ray emission from laser-matter interaction experiments, or to use the x-rays as a probe of dense matter. These

  19. Method for the fabrication of three-dimensional microstructures by deep X-ray lithography

    DOE Patents [OSTI]

    Sweatt, William C.; Christenson, Todd R.

    2005-04-05

    A method for the fabrication of three-dimensional microstructures by deep X-ray lithography (DXRL) comprises a masking process that uses a patterned mask with inclined mask holes and off-normal exposures with a DXRL beam aligned with the inclined mask holes. Microstructural features that are oriented in different directions can be obtained by using multiple off-normal exposures through additional mask holes having different orientations. Various methods can be used to block the non-aligned mask holes from the beam when using multiple exposures. A method for fabricating a precision 3D X-ray mask comprises forming an intermediate mask and a master mask on a common support membrane.

  20. Precise orientation of single crystals by a simple x-ray diffraction rocking curve method

    SciTech Connect (OSTI)

    Doucette, L.D.; Pereira da Cunha, M.; Lad, R.J.

    2005-03-01

    A simple method has been developed for accurately measuring the crystallographic orientation of a single crystal boule, employing a conventional four-circle x-ray diffraction arrangement in the rocking curve mode which relaxes the need for precise instrument and/or reference alignment. By acquiring a total of eight rocking curve measurements at specific orientations about the specimen azimuth, the absolute miscut angle between a crystal surface and the desired crystallographic plane can be resolved to within {+-}0.01 deg.

  1. Following the dynamics of matter with femtosecond precision using the X-ray streaking method

    SciTech Connect (OSTI)

    David, C.; Karvinen, P.; Sikorski, M.; Song, S.; Vartiainen, I.; Milne, C. J.; Mozzanica, A.; Kayser, Y.; Diaz, A.; Mohacsi, I.; Carini, G. A.; Herrmann, S.; Färm, E.; Ritala, M.; Fritz, D. M.; Robert, A.

    2015-01-06

    X-ray Free Electron Lasers (FELs) can produce extremely intense and very short pulses, down to below 10 femtoseconds (fs). Among the key applications are ultrafast time-resolved studies of dynamics of matter by observing responses to fast excitation pulses in a pump-probe manner. Detectors with sufficient time resolution for observing these processes are not available. Therefore, such experiments typically measure a sample's full dynamics by repeating multiple pump-probe cycles at different delay times. This conventional method assumes that the sample returns to an identical or very similar state after each cycle. Here we describe a novel approach that can provide a time trace of responses following a single excitation pulse, jitter-free, with fs timing precision. We demonstrate, in an X-ray diffraction experiment, how it can be applied to the investigation of ultrafast irreversible processes.

  2. Following the dynamics of matter with femtosecond precision using the X-ray streaking method

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

    David, C.; Karvinen, P.; Sikorski, M.; Song, S.; Vartiainen, I.; Milne, C. J.; Mozzanica, A.; Kayser, Y.; Diaz, A.; Mohacsi, I.; et al

    2015-01-06

    X-ray Free Electron Lasers (FELs) can produce extremely intense and very short pulses, down to below 10 femtoseconds (fs). Among the key applications are ultrafast time-resolved studies of dynamics of matter by observing responses to fast excitation pulses in a pump-probe manner. Detectors with sufficient time resolution for observing these processes are not available. Therefore, such experiments typically measure a sample's full dynamics by repeating multiple pump-probe cycles at different delay times. This conventional method assumes that the sample returns to an identical or very similar state after each cycle. Here we describe a novel approach that can provide amore » time trace of responses following a single excitation pulse, jitter-free, with fs timing precision. We demonstrate, in an X-ray diffraction experiment, how it can be applied to the investigation of ultrafast irreversible processes.« less

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

    DOE Patents [OSTI]

    Wilson, Bary W.; Shepard, Chester L.

    2005-02-22

    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.

  4. Feasibility study of a high-spatial resolution x-ray computed tomography using sub-pixel shift method

    SciTech Connect (OSTI)

    Yoneyama, Akio Baba, Rika; Sumitani, Kazushi; Hirai, Yasuharu

    2015-02-23

    A high-spatial resolution X-ray computed tomography (CT) adopting a sub-pixel shift method has been developed. By calculating sectional images, using plural CT datasets obtained by scanning the X-ray imager, the spatial resolution can be reduced relative to the sub-pixel size of an X-ray imager. Feasibility observations of a biomedical sample were performed using 12-keV monochromatic synchrotron radiation and a photon-counting X-ray imager 174-μm pixels in size. Four CT measurements were performed to obtain datasets at different positions of the X-ray imager. Fine sectional images were obtained successfully, and the spatial resolution was estimated as 80-μm, which corresponds to just under half the pixel size of the imager. In addition, a fine 3D image was also obtained by scanning the imager two-dimensionally.

  5. Resonant Soft X-Ray Contrast Variation Methods as Composition-Specific Probes of Thin Polymer Film Structure

    SciTech Connect (OSTI)

    Welch, Cynthia; Welch, Cynthia F.; Hjelm, Rex P.; Mang, Joseph T.; Hawley, Marilyn E.; Wrobleski, Debra A.; Orler, E. Bruce; Kortright, Jeffrey B

    2008-04-04

    We have developed complementary soft x-ray scattering and reflectometry techniques that allow for the morphological analysis of thin polymer films without resorting to chemical modification or isotopic 2 labeling. With these techniques, we achieve significant, x-ray energy-dependent contrast between carbon atoms in different chemical environments using soft x-ray resonance at the carbon edge. Because carbon-containing samples absorb strongly in this region, the scattering length density depends on both the real and imaginary parts of the atomic scattering factors. Using a model polymer film of poly(styrene-b-methyl methacrylate), we show that the soft x-ray reflectivity data is much more sensitive to these atomic scattering factors than the soft x-ray scattering data. Nevertheless, fits to both types of data yield useful morphological details on the polymer?slamellar structure that are consistent with each other and with literature values.

  6. Vertical dispersion methods in x-ray spectroscopy of high temperature plasmas

    SciTech Connect (OSTI)

    Renner, O.; Missalla, T.; Foerster, E.

    1995-12-31

    General formulae for the applying the vertical dispersion principle in x-ray spectroscopy of multiple charged ions are summarized, the characteristics of the experimental schemes based on flat and bent crystals are discussed. The unique properties of the novel spectroscopic methods, i.e., their extremely high dispersion, high spectral and 1-D spatial resolution and good collection efficiency, make them very attractive for ultrahigh-resolution spectroscopy. The examples of successful use of the vertical dispersion modifications of the double-crystal and the Johann spectrometer in diagnostics of several types of laser-generated plasma are presented.

  7. Imaging method based on attenuation, refraction and ultra-small-angle-scattering of x-rays

    DOE Patents [OSTI]

    Wernick, Miles N.; Chapman, Leroy Dean; Oltulu, Oral; Zhong, Zhong

    2005-09-20

    A method for detecting an image of an object by measuring the intensity at a plurality of positions of a transmitted beam of x-ray radiation emitted from the object as a function of angle within the transmitted beam. The intensity measurements of the transmitted beam are obtained by a crystal analyzer positioned at a plurality of angular positions. The plurality of intensity measurements are used to determine the angular intensity spectrum of the transmitted beam. One or more parameters, such as an attenuation property, a refraction property and a scatter property, can be obtained from the angular intensity spectrum and used to display an image of the object.

  8. Method and apparatus for molecular imaging using x-rays at resonance wavelengths

    DOE Patents [OSTI]

    Chapline, G.F. Jr.

    Holographic x-ray images are produced representing the molecular structure of a microscopic object, such as a living cell, by directing a beam of coherent x-rays upon the object to produce scattering of the x-rays by the object, producing interference on a recording medium between the scattered x-rays from the object and unscattered coherent x-rays and thereby producing holograms on the recording surface, and establishing the wavelength of the coherent x-rays to correspond with a molecular resonance of a constituent of such object and thereby greatly improving the contrast, sensitivity and resolution of the holograms as representations of molecular structures involving such constituent. For example, the coherent x-rays may be adjusted to the molecular resonant absorption line of nitrogen at about 401.3 eV to produce holographic images featuring molecular structures involving nitrogen.

  9. Method and apparatus for molecular imaging using X-rays at resonance wavelengths

    DOE Patents [OSTI]

    Chapline, Jr., George F.

    1985-01-01

    Holographic X-ray images are produced representing the molecular structure of a microscopic object, such as a living cell, by directing a beam of coherent X-rays upon the object to produce scattering of the X-rays by the object, producing interference on a recording medium between the scattered X-rays from the object and unscattered coherent X-rays and thereby producing holograms on the recording surface, and establishing the wavelength of the coherent X-rays to correspond with a molecular resonance of a constituent of such object and thereby greatly improving the contrast, sensitivity and resolution of the holograms as representations of molecular structures involving such constituent. For example, the coherent X-rays may be adjusted to the molecular resonant absorption line of nitrogen at about 401.3 eV to produce holographic images featuring molecular structures involving nitrogen.

  10. TU-A-9A-07: X-Ray Acoustic Computed Tomography (XACT): 100% Sensitivity to X-Ray Absorption

    SciTech Connect (OSTI)

    Xiang, L; Ahmad, M; Nikoozadeh, A; Pratx, G; Khuri-Yakub, B; Xing, L

    2014-06-15

    Purpose: To assess whether X-ray acoustic computed tomography (XACT) is more sensitive to X-ray absorption than that of the conventional X-ray imaging. Methods: First, a theoretical model was built to analyze the X-ray absorption sensitivity of XACT imaging and conventional X-ray imaging. Second, an XACT imaging system was developed to evaluate the X-ray induced acoustic signal generation as well as the sensitivity improvement over transmission x-ray imaging. Ultra-short x-ray pulses (60-nanosecond) were generated from an X-ray source operated at the energy of 150 kVp with a 10-Hz repetition rate. The X-ray pulse was synchronized with the acoustic detection via a x-ray scintillation triggering to acquire the X-ray induced acoustic signal. Results: Theoretical analysis shows that X-ray induced acoustic signal is sensitive only to the X-ray absorption, while completely insensitive to out the X-ray scattering and fluorescence. XACT has reduced background and increased contrast-to-noise ratio, and therefore has increased sensitivity compared to transmission x-ray imaging. For a 50-μm size, gadolinium insertion in tissue exposed to 40 keV X-rays; the sensitivity of XACT imaging is about 28.9 times higher than that of conventional X-ray imaging. Conclusion: X-ray acoustic computer tomography (XACT) as a new imaging modality combines X-ray absorption contrast and high ultrasonic resolution in a single modality. It is feasible to improve the imaging sensitivity with XACT imaging compared with conventional X-ray imaging. Taking advantage of the high ultrasonic resolution, it is possible to perform 3-D imaging with a single x-ray pulse with arrays of transducers without any mechanical motion of the imaging system. This single-shot capability offers the potential of reducing radiation dose by a factor of 1000, and imaging 100 times faster when compared to the conventional X-ray CT, and thus revolutionizing x-ray imaging applications in medicine and biology. The authors

  11. A real-time regional adaptive exposure method for saving dose-area product in x-ray fluoroscopy

    SciTech Connect (OSTI)

    Burion, Steve; Funk, Tobias; Speidel, Michael A.

    2013-05-15

    Purpose: Reduction of radiation dose in x-ray imaging has been recognized as a high priority in the medical community. Here the authors show that a regional adaptive exposure method can reduce dose-area product (DAP) in x-ray fluoroscopy. The authors' method is particularly geared toward providing dose savings for the pediatric population. Methods: The scanning beam digital x-ray system uses a large-area x-ray source with 8000 focal spots in combination with a small photon-counting detector. An imaging frame is obtained by acquiring and reconstructing up to 8000 detector images, each viewing only a small portion of the patient. Regional adaptive exposure was implemented by varying the exposure of the detector images depending on the local opacity of the object. A family of phantoms ranging in size from infant to obese adult was imaged in anteroposterior view with and without adaptive exposure. The DAP delivered to each phantom was measured in each case, and noise performance was compared by generating noise arrays to represent regional noise in the images. These noise arrays were generated by dividing the image into regions of about 6 mm{sup 2}, calculating the relative noise in each region, and placing the relative noise value of each region in a one-dimensional array (noise array) sorted from highest to lowest. Dose-area product savings were calculated as the difference between the ratio of DAP with adaptive exposure to DAP without adaptive exposure. The authors modified this value by a correction factor that matches the noise arrays where relative noise is the highest to report a final dose-area product savings. Results: The average dose-area product saving across the phantom family was (42 {+-} 8)% with the highest dose-area product saving in the child-sized phantom (50%) and the lowest in the phantom mimicking an obese adult (23%). Conclusions: Phantom measurements indicate that a regional adaptive exposure method can produce large DAP savings without

  12. Fluctuation X-Ray Scattering

    SciTech Connect (OSTI)

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

    2013-01-25

    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

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

    SciTech Connect (OSTI)

    Mason, Harris E.; Walsh, Stuart D. C.; DuFrane, Wyatt L.; Carroll, Susan A.

    2014-06-17

    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.

  14. X-ray generator

    DOE Patents [OSTI]

    Dawson, John M.

    1976-01-01

    Apparatus and method for producing coherent secondary x-rays that are controlled as to direction by illuminating a mixture of high z and low z gases with an intense burst of primary x-rays. The primary x-rays are produced with a laser activated plasma, and these x-rays strip off the electrons of the high z atoms in the lasing medium, while the low z atoms retain their electrons. The neutral atoms transfer electrons to highly excited states of the highly striped high z ions giving an inverted population which produces the desired coherent x-rays. In one embodiment, a laser, light beam provides a laser spark that produces the intense burst of coherent x-rays that illuminates the mixture of high z and low z gases, whereby the high z atoms are stripped while the low z ones are not, giving the desired mixture of highly ionized and neutral atoms. To this end, the laser spark is produced by injecting a laser light beam, or a plurality of beams, into a first gas in a cylindrical container having an adjacent second gas layer co-axial therewith, the laser producing a plasma and the intense primary x-rays in the first gas, and the second gas containing the high and low atomic number elements for receiving the primary x-rays, whereupon the secondary x-rays are produced therein by stripping desired ions in a neutral gas and transfer of electrons to highly excited states of the stripped ions from the unionized atoms. Means for magnetically confining and stabilizing the plasma are disclosed for controlling the direction of the x-rays.

  15. Tunable X-ray source

    DOE Patents [OSTI]

    Boyce, James R.

    2011-02-08

    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.

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

    DOE Patents [OSTI]

    Berman, Robert M.; Cohen, Isadore

    1990-01-01

    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.

  17. Method for improving x-ray diffraction determinations of residual stress in nickel-base alloys

    DOE Patents [OSTI]

    Berman, R.M.; Cohen, I.

    1988-04-26

    A process for improving the technique of measuring residual stress by x-ray diffraction in pieces of nickel-base alloys is discussed. Part of a predetermined area of the surface of a nickel-base alloy is covered with a dispersion. This exposes 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. 2 figs.

  18. Karyotyping human chromosomes by optical and x-ray ptychography methods

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

    Shemilt, Laura; Verbanis, Ephanielle; Schwenke, Joerg; Estandarte, Ana K.; Xiong, Gang; Harder, Ross; Parmar, Neha; Yusuf, Mohammed; Zhang, Fucai; Robinson, Ian K.

    2015-02-01

    Sorting and identifying chromosomes, a process known as karyotyping, is widely used to detect changes in chromosome shapes and gene positions. In a karyotype the chromosomes are identified by their size and therefore this process can be performed by measuring macroscopic structural variables. Chromosomes contain a specific number of basepairs that linearly correlate with their size; therefore, it is possible to perform a karyotype on chromosomes using their mass as an identifying factor. Here, we obtain the first images, to our knowledge, of chromosomes using the novel imaging method of ptychography. We can use the images to measure the massmoreof chromosomes and perform a partial karyotype from the results. We also obtain high spatial resolution using this technique with synchrotron source x-rays.less

  19. A method for volumetric imaging in radiotherapy using single x-ray projection

    SciTech Connect (OSTI)

    Xu, Yuan; Yan, Hao; Ouyang, Luo; Wang, Jing; Jiang, Steve B. E-mail: steve.jiang@utsouthwestern.edu Jia, Xun E-mail: steve.jiang@utsouthwestern.edu; Zhou, Linghong; Cervino, Laura

    2015-05-15

    Purpose: It is an intriguing problem to generate an instantaneous volumetric image based on the corresponding x-ray projection. The purpose of this study is to develop a new method to achieve this goal via a sparse learning approach. Methods: To extract motion information hidden in projection images, the authors partitioned a projection image into small rectangular patches. The authors utilized a sparse learning method to automatically select patches that have a high correlation with principal component analysis (PCA) coefficients of a lung motion model. A model that maps the patch intensity to the PCA coefficients was built along with the patch selection process. Based on this model, a measured projection can be used to predict the PCA coefficients, which are then further used to generate a motion vector field and hence a volumetric image. The authors have also proposed an intensity baseline correction method based on the partitioned projection, in which the first and the second moments of pixel intensities at a patch in a simulated projection image are matched with those in a measured one via a linear transformation. The proposed method has been validated in both simulated data and real phantom data. Results: The algorithm is able to identify patches that contain relevant motion information such as the diaphragm region. It is found that an intensity baseline correction step is important to remove the systematic error in the motion prediction. For the simulation case, the sparse learning model reduced the prediction error for the first PCA coefficient to 5%, compared to the 10% error when sparse learning was not used, and the 95th percentile error for the predicted motion vector was reduced from 2.40 to 0.92 mm. In the phantom case with a regular tumor motion, the predicted tumor trajectory was successfully reconstructed with a 0.82 mm error for tumor center localization compared to a 1.66 mm error without using the sparse learning method. When the tumor motion

  20. A grating-based single-shot x-ray phase contrast and diffraction method for in vivo imaging

    SciTech Connect (OSTI)

    Bennett, Eric E.; Kopace, Rael; Stein, Ashley F.; Wen Han

    2010-11-15

    Purpose: The purpose of this study is to develop a single-shot version of the grating-based phase contrast x-ray imaging method and demonstrate its capability of in vivo animal imaging. Here, the authors describe the principle and experimental results. They show the source of artifacts in the phase contrast signal and optimal designs that minimize them. They also discuss its current limitations and ways to overcome them. Methods: A single lead grid was inserted midway between an x-ray tube and an x-ray camera in the planar radiography setting. The grid acted as a transmission grating and cast periodic dark fringes on the camera. The camera had sufficient spatial resolution to resolve the fringes. Refraction and diffraction in the imaged object manifested as position shifts and amplitude attenuation of the fringes, respectively. In order to quantify these changes precisely without imposing a fixed geometric relationship between the camera pixel array and the fringes, a spatial harmonic method in the Fourier domain was developed. The level of the differential phase (refraction) contrast as a function of hardware specifications and device geometry was derived and used to guide the optimal placement of the grid and object. Both ex vivo and in vivo images of rodent extremities were collected to demonstrate the capability of the method. The exposure time using a 50 W tube was 28 s. Results: Differential phase contrast images of glass beads acquired at various grid and object positions confirmed theoretical predictions of how phase contrast and extraneous artifacts vary with the device geometry. In anesthetized rats, a single exposure yielded artifact-free images of absorption, differential phase contrast, and diffraction. Differential phase contrast was strongest at bone-soft tissue interfaces, while diffraction was strongest in bone. Conclusions: The spatial harmonic method allowed us to obtain absorption, differential phase contrast, and diffraction images, all from a

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

    DOE Patents [OSTI]

    Edwards, Jr., David; Lanni, Christopher P.

    1981-01-01

    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.

  2. X-ray lithography source

    DOE Patents [OSTI]

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

    1991-12-31

    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.

  3. X-ray lithography source

    DOE Patents [OSTI]

    Piestrup, Melvin A.; Boyers, David G.; Pincus, Cary

    1991-01-01

    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.

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

    SciTech Connect (OSTI)

    Bionta, M. R.; Hartmann, N.; 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.; Nicholson, D. J.; Cryan, J. P.; Baker, K.; Kane, D. J.; and others

    2014-08-15

    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 10100 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.

  5. Chromatic X-ray magnifying method and apparatus by Bragg reflective planes on the surface of Abbe sphere

    DOE Patents [OSTI]

    Thoe, Robert S.

    1991-01-01

    Method and apparatus for producing sharp, chromatic, magnified images of X-ray emitting objects, are provided. The apparatus, which constitutes an X-ray microscope or telescope, comprises a connected collection of Bragg reflecting planes, comprised of either a bent crystal or a synthetic multilayer structure, disposed on and adjacent to a locus determined by a spherical surface. The individual Bragg planes are spatially oriented to Bragg reflect radiation from the object location toward the image location. This is accomplished by making the Bragg planes spatially coincident with the surfaces of either a nested series of prolate ellipsoids of revolution, or a nested series of spheres. The spacing between the Bragg reflecting planes can be tailored to control the wavelengths and the amount of the X-radiation that is Bragg reflected to form the X-ray image.

  6. Properties of CO/sub 2/ laser produced long-life plasmas observed by x-ray spectroscopic methods

    SciTech Connect (OSTI)

    Daido, H.; Nishihara, K.; Mima, K.; Kitagawa, Y.; Nakai, S.; Yamanaka, C.; Hasegawa, A.

    1988-03-01

    We present the properties of shell confinement long-life plasmas produced by a CO/sub 2/ laser. The temperature measurement for parylene shell targets based on the x-ray spectroscopic method gives the electron temperature of more than 500 eV at the center of a 1-mm-diam target. An enchanced confinement time is obtained in a thick gold shell (100 ..mu..m thick) target coated internally with parylene. The duration of the x ray emitted from the hot core in a 3-mm-diam target of this type is 34 ns, while the laser pulse duration is 1 ns. The long duration of the x-ray manifests the hot core plasma lifetime; the observed duration presents a strong evidence of thermal insulation by the self-generated magnetic field.

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

    DOE Patents [OSTI]

    Warburton, W.K.; Hubbard, B.

    1999-02-09

    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 is disclosed. 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. 13 figs.

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

    DOE Patents [OSTI]

    Warburton, William K.; Hubbard, Bradley

    1999-01-01

    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.

  9. Apparatus and method for nanoflow liquid jet and serial femtosecond x-ray protein crystallography

    DOE Patents [OSTI]

    Bogan, Michael J.; Laksmono, Hartawan; Sierra, Raymond G.

    2016-03-01

    Techniques for nanoflow serial femtosecond x-ray protein crystallography include providing a sample fluid by mixing a plurality of a first target of interest with a carrier fluid and injecting the sample fluid into a vacuum chamber at a rate less than about 4 microliters per minute. In some embodiments, the carrier fluid has a viscosity greater than about 3 centipoise.

  10. 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.

    2000-01-17

    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.

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

    DOE Patents [OSTI]

    Warburton, W.K.; Hubbard, B.

    1997-11-04

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

    DOE Patents [OSTI]

    Warburton, William K.; Hubbard, Bradley

    1997-01-01

    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.

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

    DOE Patents [OSTI]

    Hau-Riege, Stefan Peter

    2007-05-01

    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.

  14. 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.

    2010-06-22

    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.

  15. Systems and methods for detecting an image of an object using multi-beam imaging from an X-ray beam having a polychromatic distribution

    DOE Patents [OSTI]

    Parham, Christopher A; Zhong, Zhong; Pisano, Etta; Connor, Jr., Dean M

    2015-03-03

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

  16. Simple Method to Estimate Mean Heart Dose From Hodgkin Lymphoma Radiation Therapy According to Simulation X-Rays

    SciTech Connect (OSTI)

    Nimwegen, Frederika A. van; Cutter, David J.; Schaapveld, Michael; Rutten, Annemarieke; Kooijman, Karen; Krol, Augustinus D.G.; Janus, Cécile P.M.; Darby, Sarah C.; Leeuwen, Flora E. van; Aleman, Berthe M.P.

    2015-05-01

    Purpose: To describe a new method to estimate the mean heart dose for Hodgkin lymphoma patients treated several decades ago, using delineation of the heart on radiation therapy simulation X-rays. Mean heart dose is an important predictor for late cardiovascular complications after Hodgkin lymphoma (HL) treatment. For patients treated before the era of computed tomography (CT)-based radiotherapy planning, retrospective estimation of radiation dose to the heart can be labor intensive. Methods and Materials: Patients for whom cardiac radiation doses had previously been estimated by reconstruction of individual treatments on representative CT data sets were selected at random from a case–control study of 5-year Hodgkin lymphoma survivors (n=289). For 42 patients, cardiac contours were outlined on each patient's simulation X-ray by 4 different raters, and the mean heart dose was estimated as the percentage of the cardiac contour within the radiation field multiplied by the prescribed mediastinal dose and divided by a correction factor obtained by comparison with individual CT-based dosimetry. Results: According to the simulation X-ray method, the medians of the mean heart doses obtained from the cardiac contours outlined by the 4 raters were 30 Gy, 30 Gy, 31 Gy, and 31 Gy, respectively, following prescribed mediastinal doses of 25-42 Gy. The absolute-agreement intraclass correlation coefficient was 0.93 (95% confidence interval 0.85-0.97), indicating excellent agreement. Mean heart dose was 30.4 Gy with the simulation X-ray method, versus 30.2 Gy with the representative CT-based dosimetry, and the between-method absolute-agreement intraclass correlation coefficient was 0.87 (95% confidence interval 0.80-0.95), indicating good agreement between the two methods. Conclusion: Estimating mean heart dose from radiation therapy simulation X-rays is reproducible and fast, takes individual anatomy into account, and yields results comparable to the labor

  17. 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.

    2012-01-15

    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.

  18. Phase-based x-ray scatteringA possible method to detect cancer cells in a very early stage

    SciTech Connect (OSTI)

    Feye-Treimer, U. Treimer, W.

    2014-05-15

    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 nucleusplasma 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 cellcell 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

  19. X-ray photoelectron spectroscopy of negative electrodes from high-power lithium-ion cells showing various levels of power fade

    SciTech Connect (OSTI)

    Herstedt, Marie; Abraham, Daniel P.; Kerr, John B.

    2004-02-28

    High-power lithium-ion cells for transportation applications are being developed and studied at Argonne National Laboratory. The current generation of cells containing LiNi{sub 0.8}Co{sub 0.15}Al{sub 0.05}O{sub 2}-based cathodes, graphite-based anodes, and LiPF6-based electrolytes show loss of capacity and power during accelerated testing at elevated temperatures. Negative electrode samples harvested from some cells that showed varying degrees of power and capacity fade were examined by X-ray photoelectron spectroscopy (XPS). The samples exhibited a surface film on the graphite, which was thicker on samples from cells that showed higher fade. Furthermore, solvent-based compounds were dominant on samples from low power fade cells, whereas LiPF{sub 6}-based products were dominant on samples from high power fade cells. The effect of sample rinsing and air exposure is discussed. Mechanisms are proposed to explain the formation of compounds suggested by the XPS data.

  20. High speed optical and X-ray methods for evaluating laser-generated shock-wave in materials

    SciTech Connect (OSTI)

    Paisley, D.; Swift, D.

    2000-11-01

    Optical diagnostic techniques including interferometry, electronic streak photography, and transient x-ray diffraction are used to study the dynamic material response to shock loading by direct laser irradiation and impact by laser-launched plates. The Los Alamos Trident laser is one of several lasers that have been used to generate shocks of 10 Kbar to several Mbar in single crystal and polycrystalline materials. Incorporating optical velocity interferometry (line-VISAR and point-VISAR) with transient x-ray diffraction can provide a complete understanding of the dynamic material response to shock compression and release. Laser-launched flyer plates provide an ideal method to generate one-dimensional shocks in materials. The quality of the one-dimensionality of the launch and acceleration of plates is evaluated by line-imaging VISA.R. The line-imaging VISAR images the fringes along a line across the diameter of the plate. Each fringe maxima and minima provide acceleration and velocity information at the specific point on the plate. By varying the fringe constant number of fringes and fringe spacing on the plate, detailed experimental data can be obtained. For our experiments, most plates are 3-mm diameter and accelerated to 0.2-->6 km/sec.

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

    SciTech Connect (OSTI)

    Nagasaka, Masanari Kosugi, Nobuhiro; Yuzawa, Hayato; Horigome, Toshio

    2014-10-15

    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. X-Ray Diagnostics

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

    including film developing and scanning, and image plate scanning. Related images X-ray framing camera being loaded into the TIM in the Trident North Target Area. X-ray framing...

  3. Construction of a magnetic bottle spectrometer and its application to pulse duration measurement of X-ray laser using a pump-probe method

    SciTech Connect (OSTI)

    Namba, S.; Hasegawa, N.; Kishimoto, M.; Nishikino, M.; Ishino, M.; Kawachi, T.

    2015-11-15

    To characterize the temporal evolution of ultrashort X-ray pulses emitted by laser plasmas using a pump-probe method, a magnetic bottle time-of-flight electron spectrometer is constructed. The design is determined by numerical calculations of a mirror magnetic field and of the electron trajectory in a flight tube. The performance of the spectrometer is characterized by measuring the electron spectra of xenon atoms irradiated with a laser-driven plasma X-ray pulse. In addition, two-color above-threshold ionization (ATI) experiment is conducted for measurement of the X-ray laser pulse duration, in which xenon atoms are simultaneously irradiated with an X-ray laser pump and an IR laser probe. The correlation in the intensity of the sideband spectra of the 4d inner-shell photoelectrons and in the time delay of the two laser pulses yields an X-ray pulse width of 5.7 ps, in good agreement with the value obtained using an X-ray streak camera.

  4. 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.

    2007-12-04

    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.

  5. 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.

    2007-01-02

    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.

  6. X-ray microtomographic scanners

    SciTech Connect (OSTI)

    Syryamkin, V. I. Klestov, S. A.

    2015-11-17

    The article studies the operating procedures of an X-ray microtomographic scanner and the module of reconstruction and analysis 3D-image of a test sample in particular. An algorithm for 3D-image reconstruction based on image shadow projections and mathematical methods of the processing are described. Chapter 1 describes the basic principles of X-ray tomography and general procedures of the device developed. Chapters 2 and 3 are devoted to the problem of resources saving by the system during the X-ray tomography procedure, which is achieved by preprocessing of the initial shadow projections. Preprocessing includes background noise removing from the images, which reduces the amount of shadow projections in general and increases the efficiency of the group shadow projections compression. In conclusion, the main applications of X-ray tomography are presented.

  7. Method and apparatus for enhanced sensitivity filmless medical x-ray imaging, including three-dimensional imaging

    DOE Patents [OSTI]

    Parker, Sherwood

    1995-01-01

    A filmless X-ray imaging system includes at least one X-ray source, upper and lower collimators, and a solid-state detector array, and can provide three-dimensional imaging capability. The X-ray source plane is distance z.sub.1 above upper collimator plane, distance z.sub.2 above the lower collimator plane, and distance z.sub.3 above the plane of the detector array. The object to be X-rayed is located between the upper and lower collimator planes. The upper and lower collimators and the detector array are moved horizontally with scanning velocities v.sub.1, v.sub.2, v.sub.3 proportional to z.sub.1, z.sub.2 and z.sub.3, respectively. The pattern and size of openings in the collimators, and between detector positions is proportional such that similar triangles are always defined relative to the location of the X-ray source. X-rays that pass through openings in the upper collimator will always pass through corresponding and similar openings in the lower collimator, and thence to a corresponding detector in the underlying detector array. Substantially 100% of the X-rays irradiating the object (and neither absorbed nor scattered) pass through the lower collimator openings and are detected, which promotes enhanced sensitivity. A computer system coordinates repositioning of the collimators and detector array, and X-ray source locations. The computer system can store detector array output, and can associate a known X-ray source location with detector array output data, to provide three-dimensional imaging. Detector output may be viewed instantly, stored digitally, and/or transmitted electronically for image viewing at a remote site.

  8. Method and apparatus for enhanced sensitivity filmless medical x-ray imaging, including three-dimensional imaging

    DOE Patents [OSTI]

    Parker, S.

    1995-10-24

    A filmless X-ray imaging system includes at least one X-ray source, upper and lower collimators, and a solid-state detector array, and can provide three-dimensional imaging capability. The X-ray source plane is distance z{sub 1} above upper collimator plane, distance z{sub 2} above the lower collimator plane, and distance z{sub 3} above the plane of the detector array. The object to be X-rayed is located between the upper and lower collimator planes. The upper and lower collimators and the detector array are moved horizontally with scanning velocities v{sub 1}, v{sub 2}, v{sub 3} proportional to z{sub 1}, z{sub 2} and z{sub 3}, respectively. The pattern and size of openings in the collimators, and between detector positions is proportional such that similar triangles are always defined relative to the location of the X-ray source. X-rays that pass through openings in the upper collimator will always pass through corresponding and similar openings in the lower collimator, and thence to a corresponding detector in the underlying detector array. Substantially 100% of the X-rays irradiating the object (and neither absorbed nor scattered) pass through the lower collimator openings and are detected, which promotes enhanced sensitivity. A computer system coordinates repositioning of the collimators and detector array, and X-ray source locations. The computer system can store detector array output, and can associate a known X-ray source location with detector array output data, to provide three-dimensional imaging. Detector output may be viewed instantly, stored digitally, and/or transmitted electronically for image viewing at a remote site. 5 figs.

  9. X-ray lithography using holographic images

    DOE Patents [OSTI]

    Howells, Malcolm R.; Jacobsen, Chris

    1995-01-01

    A non-contact X-ray projection lithography method for producing a desired X-ray image on a selected surface of an X-ray-sensitive material, such as photoresist material on a wafer, the desired X-ray image having image minimum linewidths as small as 0.063 .mu.m, or even smaller. A hologram and its position are determined that will produce the desired image on the selected surface when the hologram is irradiated with X-rays from a suitably monochromatic X-ray source of a selected wavelength .lambda.. On-axis X-ray transmission through, or off-axis X-ray reflection from, a hologram may be used here, with very different requirements for monochromaticity, flux and brightness of the X-ray source. For reasonable penetration of photoresist materials by X-rays produced by the X-ray source, the wavelength X, is preferably chosen to be no more than 13.5 nm in one embodiment and more preferably is chosen in the range 1-5 nm in the other embodiment. A lower limit on linewidth is set by the linewidth of available microstructure writing devices, such as an electron beam.

  10. An improved method for flat-field correction of flat panel x-ray detector

    SciTech Connect (OSTI)

    Kwan, Alexander L.C.; Seibert, J. Anthony; Boone, John M.

    2006-02-15

    In this Technical Note, the effects of different flat-field techniques are examined for a cesium iodide flat panel detector, which exhibited a slightly nonlinear exposure response. The results indicate that the variable flat-field correction method with the appropriate polynomial fit provides excellent correction throughout the entire exposure range. The averaged normalized variation factor, used to assess the nonuniformity of the flat-field correction, decreased from 30.76 for the fixed correction method to 4.13 for the variable flat-field correction method with a fourth-order polynomial fit for the 60 kVp spectrum, and from 16.42 to 3.97 for the 95 kVp spectrum.

  11. X-ray microscopy. Beyond ensemble averages

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

    Ice, Gene E.; Budai, John D.

    2015-06-23

    This work exemplifies emerging tools to characterize local materials structure and dynamics, made possible by powerful X-ray synchrotron and transmission electron microscopy methods.

  12. 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.

  13. X-ray beamsplitter

    DOE Patents [OSTI]

    Ceglio, Natale M.; Stearns, Daniel S.; Hawryluk, Andrew M.; Barbee, Jr., Troy W.

    1989-01-01

    An x-ray beamsplitter which splits an x-ray beam into two coherent parts by reflecting and transmitting some fraction of an incident beam has applications for x-ray interferometry, x-ray holography, x-ray beam manipulation, and x-ray laser cavity output couplers. The beamsplitter is formed of a wavelength selective multilayer thin film supported by a very thin x-ray transparent membrane. The beamsplitter resonantly transmits and reflects x-rays through thin film interference effects. A thin film is formed of 5-50 pairs of alternate Mo/Si layers with a period of 20-250 A. The support membrane is 10-200 nm of silicon nitride or boron nitride. The multilayer/support membrane structure is formed across a window in a substrate by first forming the structure on a solid substrate and then forming a window in the substrate to leave a free-standing structure over the window.

  14. X-ray beamsplitter

    DOE Patents [OSTI]

    Ceglio, N.M.; Stearns, D.G.; Hawryluk, A.M.; Barbee, T.W. Jr.

    1987-08-07

    An x-ray beamsplitter which splits an x-ray beam into two coherent parts by reflecting and transmitting some fraction of an incident beam has applications for x-ray interferometry, x-ray holography, x-ray beam manipulation, and x-ray laser cavity output couplers. The beamsplitter is formed of a wavelength selective multilayer thin film supported by a very thin x-ray transparent membrane. The beamsplitter resonantly transmits and reflects x-rays through thin film interference effects. A thin film is formed of 5--50 pairs of alternate Mo/Si layers with a period of 20--250 A. The support membrane is 10--200 nm of silicon nitride or boron nitride. The multilayer/support membrane structure is formed across a window in a substrate by first forming the structure on a solid substrate and then forming a window in the substrate to leave a free-standing structure over the window. 6 figs.

  15. X-ray laser

    DOE Patents [OSTI]

    Nilsen, Joseph

    1991-01-01

    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.

  16. SMB, X-Ray Spectroscopy & Imaging

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

    Home » X-Ray Spectroscopy & Imaging X-Ray Spectroscopy & Imaging SSRL has five hard X-ray Spectroscopy beamlines and three Microfocus Imaging beamlines dedicated to Biological and Biomedical research funded by the NIH and DOE-BER. The SMB group supports and develops technical instrumentation and theoretical methods for state-of-the-art tender and hard X-ray spectroscopy and EXAFS studies on metalloproteins, cofactors and metals in medicine. The SMB group has also contributed to the

  17. Spatiotemporal Monte Carlo transport methods in x-ray semiconductor detectors: Application to pulse-height spectroscopy in a-Se

    SciTech Connect (OSTI)

    Fang Yuan; Badal, Andreu; Allec, Nicholas; Karim, Karim S.; Badano, Aldo

    2012-01-15

    Purpose: The authors describe a detailed Monte Carlo (MC) method for the coupled transport of ionizing particles and charge carriers in amorphous selenium (a-Se) semiconductor x-ray detectors, and model the effect of statistical variations on the detected signal. Methods: A detailed transport code was developed for modeling the signal formation process in semiconductor x-ray detectors. The charge transport routines include three-dimensional spatial and temporal models of electron-hole pair transport taking into account recombination and trapping. Many electron-hole pairs are created simultaneously in bursts from energy deposition events. Carrier transport processes include drift due to external field and Coulombic interactions, and diffusion due to Brownian motion. Results: Pulse-height spectra (PHS) have been simulated with different transport conditions for a range of monoenergetic incident x-ray energies and mammography radiation beam qualities. Two methods for calculating Swank factors from simulated PHS are shown, one using the entire PHS distribution, and the other using the photopeak. The latter ignores contributions from Compton scattering and K-fluorescence. Comparisons differ by approximately 2% between experimental measurements and simulations. Conclusions: The a-Se x-ray detector PHS responses simulated in this work include three-dimensional spatial and temporal transport of electron-hole pairs. These PHS were used to calculate the Swank factor and compare it with experimental measurements. The Swank factor was shown to be a function of x-ray energy and applied electric field. Trapping and recombination models are all shown to affect the Swank factor.

  18. X-Ray Detection

    Office of Scientific and Technical Information (OSTI)

    ratio, I I on I off , recorded with plus (+, blue) and minus (-, red) x-ray helicities. This measurement was taken at -5 mA, which corresponds to a current...

  19. Compound refractive X-ray lens

    DOE Patents [OSTI]

    Nygren, David R.; Cahn, Robert; Cederstrom, Bjorn; Danielsson, Mats; Vestlund, Jonas

    2000-01-01

    An apparatus and method for focusing X-rays. In one embodiment, his invention is a commercial-grade compound refractive X-ray lens. The commercial-grade compound refractive X-ray lens includes a volume of low-Z material. The volume of low-Z material has a first surface which is adapted to receive X-rays of commercially-applicable power emitted from a commercial-grade X-ray source. The volume of low-Z material also has a second surface from which emerge the X-rays of commercially-applicable power which were received at the first surface. Additionally, the commercial-grade compound refractive X-ray lens includes a plurality of openings which are disposed between the first surface and the second surface. The plurality of openings are oriented such that the X-rays of commercially-applicable power which are received at the first surface, pass through the volume of low-Z material and through the plurality openings. In so doing, the X-rays which emerge from the second surface are refracted to a focal point.

  20. X-ray Imaging Workshop

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

    microscopy (PEEM), angle resolved photoemission spectroscopy (ARPES), coherent diffraction imaging, x-ray microscopy, micro-tomography, holographic imaging, and x-ray...

  1. X-ray fluorescence mapping

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

    X-Ray Microscopy and Imaging: X-ray Fluorescence Mapping Of increasing scientific interest is the detection, quantification and mapping of elemental content of samples, often down...

  2. System for phase-contrast x-ray radiography using X pinch radiation and a method thereof

    DOE Patents [OSTI]

    Chandler, Katherine; Chelkovenko, Tatiana; Hammer, David; Pikuz, Sergei; Sinars, Daniel; Song, Byungmoo

    2007-11-06

    A radiograph system with an anode plate, a cathode plate, and a power source coupled to said anode plate and the cathode plate. At least two wires coupled between the anode plate and the cathode plate provide a configuration to form an X-pinch having a photon source size of less than five microns at energies above 2.5 keV. Material at the configuration forming the X-pinch vaporizes upon application of a suitable current to the wires forming a dense hot plasma and emitting a single x-ray pulse with sufficient photons having energies in the range of from about 2.5 keV to about 20 keV to provide a phase contrast image of an object in the path of the photons. Multiple simultaneous images may be formed of a plurality of objects. Suitable filters and x-ray detectors are provided.

  3. Laser plasma x-ray source for ultrafast time-resolved x-ray absorption spectroscopy

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

    Miaja-Avila, L.; O'Neil, G. C.; Uhlig, J.; Cromer, C. L.; Dowell, M. L.; Jimenez, R.; Hoover, A. S.; Silverman, K. L.; Ullom, J. N.

    2015-03-02

    We describe a laser-driven x-ray plasma source designed for ultrafast x-ray absorption spectroscopy. The source is comprised of a 1 kHz, 20 W, femtosecond pulsed infrared laser and a water target. We present the x-ray spectra as a function of laser energy and pulse duration. Additionally, we investigate the plasma temperature and photon flux as we vary the laser energy. We obtain a 75 μm FWHM x-ray spot size, containing ~106 photons/s, by focusing the produced x-rays with a polycapillary optic. Since the acquisition of x-ray absorption spectra requires the averaging of measurements from >107 laser pulses, we also presentmore » data on the source stability, including single pulse measurements of the x-ray yield and the x-ray spectral shape. In single pulse measurements, the x-ray flux has a measured standard deviation of 8%, where the laser pointing is the main cause of variability. Further, we show that the variability in x-ray spectral shape from single pulses is low, thus justifying the combining of x-rays obtained from different laser pulses into a single spectrum. Finally, we show a static x-ray absorption spectrum of a ferrioxalate solution as detected by a microcalorimeter array. Altogether, our results demonstrate that this water-jet based plasma source is a suitable candidate for laboratory-based time-resolved x-ray absorption spectroscopy experiments.« less

  4. Laser plasma x-ray source for ultrafast time-resolved x-ray absorption spectroscopy

    SciTech Connect (OSTI)

    Miaja-Avila, L.; O'Neil, G. C.; Uhlig, J.; Cromer, C. L.; Dowell, M. L.; Jimenez, R.; Hoover, A. S.; Silverman, K. L.; Ullom, J. N.

    2015-03-02

    We describe a laser-driven x-ray plasma source designed for ultrafast x-ray absorption spectroscopy. The source is comprised of a 1 kHz, 20 W, femtosecond pulsed infrared laser and a water target. We present the x-ray spectra as a function of laser energy and pulse duration. Additionally, we investigate the plasma temperature and photon flux as we vary the laser energy. We obtain a 75 μm FWHM x-ray spot size, containing ~106 photons/s, by focusing the produced x-rays with a polycapillary optic. Since the acquisition of x-ray absorption spectra requires the averaging of measurements from >107 laser pulses, we also present data on the source stability, including single pulse measurements of the x-ray yield and the x-ray spectral shape. In single pulse measurements, the x-ray flux has a measured standard deviation of 8%, where the laser pointing is the main cause of variability. Further, we show that the variability in x-ray spectral shape from single pulses is low, thus justifying the combining of x-rays obtained from different laser pulses into a single spectrum. Finally, we show a static x-ray absorption spectrum of a ferrioxalate solution as detected by a microcalorimeter array. Altogether, our results demonstrate that this water-jet based plasma source is a suitable candidate for laboratory-based time-resolved x-ray absorption spectroscopy experiments.

  5. Spherical grating based x-ray Talbot interferometry

    SciTech Connect (OSTI)

    Cong, Wenxiang E-mail: xiy2@rpi.edu Xi, Yan E-mail: xiy2@rpi.edu Wang, Ge E-mail: xiy2@rpi.edu

    2015-11-15

    Purpose: Grating interferometry is a state-of-the-art x-ray imaging approach, which can acquire information on x-ray attenuation, phase shift, and small-angle scattering simultaneously. Phase-contrast imaging and dark-field imaging are very sensitive to microstructural variation and offers superior contrast resolution for biological soft tissues. However, a common x-ray tube is a point-like source. As a result, the popular planar grating imaging configuration seriously restricts the flux of photons and decreases the visibility of signals, yielding a limited field of view. The purpose of this study is to extend the planar x-ray grating imaging theory and methods to a spherical grating scheme for a wider range of preclinical and clinical applications. Methods: A spherical grating matches the wave front of a point x-ray source very well, allowing the perpendicular incidence of x-rays on the grating to achieve a higher visibility over a larger field of view than the planer grating counterpart. A theoretical analysis of the Talbot effect for spherical grating imaging is proposed to establish a basic foundation for x-ray spherical gratings interferometry. An efficient method of spherical grating imaging is also presented to extract attenuation, differential phase, and dark-field images in the x-ray spherical grating interferometer. Results: Talbot self-imaging with spherical gratings is analyzed based on the Rayleigh–Sommerfeld diffraction formula, featuring a periodic angular distribution in a polar coordinate system. The Talbot distance is derived to reveal the Talbot self-imaging pattern. Numerical simulation results show the self-imaging phenomenon of a spherical grating interferometer, which is in agreement with the theoretical prediction. Conclusions: X-ray Talbot interferometry with spherical gratings has a significant practical promise. Relative to planar grating imaging, spherical grating based x-ray Talbot interferometry has a larger field of view and

  6. X-ray microtomography

    SciTech Connect (OSTI)

    Landis, Eric N.; Keane, Denis T.

    2010-12-15

    In this tutorial, we describe X-ray microtomography as a technique to nondestructively characterize material microstructure in three dimensions at a micron level spatial resolution. While commercially available laboratory scale instrumentation is available, we focus our attention on synchrotron-based systems, where we can exploit a high flux, monochromatic X-ray beam to produce high fidelity three-dimensional images. A brief description of the physics and the mathematical analysis behind the technique is followed by example applications to specific materials characterization problems, with a particular focus on the utilization of three-dimensional image processing that can be used to extract a wide range of useful information.

  7. Method for characterization of a spherically bent crystal for K.alpha. X-ray imaging of laser plasmas using a focusing monochromator geometry

    DOE Patents [OSTI]

    Kugland, Nathan; Doeppner, Tilo; Glenzer, Siegfried; Constantin, Carmen; Niemann, Chris; Neumayer, Paul

    2015-04-07

    A method is provided for characterizing spectrometric properties (e.g., peak reflectivity, reflection curve width, and Bragg angle offset) of the K.alpha. emission line reflected narrowly off angle of the direct reflection of a bent crystal and in particular of a spherically bent quartz 200 crystal by analyzing the off-angle x-ray emission from a stronger emission line reflected at angles far from normal incidence. The bent quartz crystal can therefore accurately image argon K.alpha. x-rays at near-normal incidence (Bragg angle of approximately 81 degrees). The method is useful for in-situ calibration of instruments employing the crystal as a grating by first operating the crystal as a high throughput focusing monochromator on the Rowland circle at angles far from normal incidence (Bragg angle approximately 68 degrees) to make a reflection curve with the He-like x-rays such as the He-.alpha. emission line observed from a laser-excited plasma.

  8. 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.

    1997-12-01

    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.

  9. X-ray beam finder

    DOE Patents [OSTI]

    Gilbert, H.W.

    1983-06-16

    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.

  10. 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.

    1998-06-30

    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.

  11. 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.

    1998-01-01

    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.

  12. Method based on atomic photoionization for spot-size measurement on focused soft x-ray free-electron laser beams

    SciTech Connect (OSTI)

    Sorokin, A. A.; Gottwald, A.; Hoehl, A.; Kroth, U.; Schoeppe, H.; Ulm, G.; Richter, M.; Bobashev, S. V.; Domracheva, I. V.; Smirnov, D. N.; Tiedtke, K.; Duesterer, S.; Feldhaus, J.; Hahn, U.; Jastrow, U.; Kuhlmann, M.; Nunez, T.; Ploenjes, E.; Treusch, R.

    2006-11-27

    A method has been developed and applied to measure the beam waist and spot size of a focused soft x-ray beam at the free-electron laser FLASH of the Deutsches Elektronen-Synchrotron in Hamburg. The method is based on a saturation effect upon atomic photoionization and represents an indestructible tool for the characterization of powerful beams of ionizing electromagnetic radiation. At the microfocus beamline BL2 at FLASH, a full width at half maximum focus diameter of (15{+-}2) {mu}m was determined.

  13. X-Ray Diffraction Microscopy of Magnetic Structures

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

    X-Ray Diffraction Microscopy of Magnetic Structures Print science brief icon Scientists working at ALS Beamline 12.0.2.2 have demonstrated a new x-ray technique for producing short-exposure nanoscale images of the magnetic structure of materials. The new method combines aspects of coherent x-ray diffraction, which can determine 3-D charge distributions, and resonant magnetic scattering, which is sensitive to magnetic structures. Physicists have used coherent x-ray diffraction to measure the

  14. X-Ray Diffraction Microscopy of Magnetic Structures

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

    X-Ray Diffraction Microscopy of Magnetic Structures Print science brief icon Scientists working at ALS Beamline 12.0.2.2 have demonstrated a new x-ray technique for producing short-exposure nanoscale images of the magnetic structure of materials. The new method combines aspects of coherent x-ray diffraction, which can determine 3-D charge distributions, and resonant magnetic scattering, which is sensitive to magnetic structures. Physicists have used coherent x-ray diffraction to measure the

  15. X-Ray Diffraction Microscopy of Magnetic Structures

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

    X-Ray Diffraction Microscopy of Magnetic Structures Print science brief icon Scientists working at ALS Beamline 12.0.2.2 have demonstrated a new x-ray technique for producing short-exposure nanoscale images of the magnetic structure of materials. The new method combines aspects of coherent x-ray diffraction, which can determine 3-D charge distributions, and resonant magnetic scattering, which is sensitive to magnetic structures. Physicists have used coherent x-ray diffraction to measure the

  16. Probing convex polygons with X-rays

    SciTech Connect (OSTI)

    Edelsbrunner, H.; Skiena, S.S. )

    1988-10-01

    An X-ray probe through a polygon measures the length of intersection between a line and the polygon. This paper considers the properties of various classes of X-ray probes, and shows how they interact to give finite strategies for completely describing convex n-gons. It is shown that (3n/2)+6 probes are sufficient to verify a specified n-gon, while for determining convex polygons (3n-1)/2 X-ray probes are necessary and 5n+O(1) sufficient, with 3n+O(1) sufficient given that a lower bound on the size of the smallest edge of P is known.

  17. Sandia National Laboratories: X-ray vision

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

    The Sandia-developed X-Ray Toolkit, or XTK, is a specialized X-ray visualization tool to help bomb disposal squads make fast, accurate, and precise assessments of potentially dangerous devices such as pipe bombs and IEDs. The image here, captured via the XTK software package using its unique image-stitching capability, shows the inner workings of a mock IED. Facebook Twitter YouTube Flickr RSS News X-ray vision By Nancy Salem Photography By Randy Montoya Thursday, September 01, 2016 Sandia, UNM

  18. Soft-x-ray

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

    Soft-x-ray emission, plasma equilibrium, and fluctuation studies on Madison Symmetric Torus C. Xiao Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin and Department of Physics and Engineering Physics, University of Saskatchewan, Saskatoon, Canada P. Franz Consorzio RFX-Associazione EURATOM ENEA Sulla Fusione, Italy and Istituto Nazionale di Fisica della Materia, Unita' di Ricerca di Padova, Italy B. E. Chapman and D. Craig Department of Physics, University of

  19. SMB, X-ray Emission Spectroscopy

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

    include X-ray Emission Spectroscopy (XES), Resonant Inelastic X-ray Scattering (RIXS), High Energy Resolution Fluorescence Detection (HERFD) and X-ray Raman Spectroscopy (XRS). ...

  20. TV-based conjugate gradient method and discrete L-curve for few-view CT reconstruction of X-ray in vivo data

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

    Yang, Xiaoli; Hofmann, Ralf; Dapp, Robin; van de Kamp, Thomas; Rolo, Tomy dos Santos; Xiao, Xianghui; Moosmann, Julian; Kashef, Jubin; Stotzka, Rainer

    2015-01-01

    High-resolution, three-dimensional (3D) imaging of soft tissues requires the solution of two inverse problems: phase retrieval and the reconstruction of the 3D image from a tomographic stack of two-dimensional (2D) projections. The number of projections per stack should be small to accommodate fast tomography of rapid processes and to constrain X-ray radiation dose to optimal levels to either increase the duration o fin vivo time-lapse series at a given goal for spatial resolution and/or the conservation of structure under X-ray irradiation. In pursuing the 3D reconstruction problem in the sense of compressive sampling theory, we propose to reduce the numbermoreof projections by applying an advanced algebraic technique subject to the minimisation of the total variation (TV) in the reconstructed slice. This problem is formulated in a Lagrangian multiplier fashion with the parameter value determined by appealing to a discrete L-curve in conjunction with a conjugate gradient method. The usefulness of this reconstruction modality is demonstrated for simulated and in vivo data, the latter acquired in parallel-beam imaging experiments using synchrotron radiation.less

  1. TV-based conjugate gradient method and discrete L-curve for few-view CT reconstruction of X-ray in vivo data

    SciTech Connect (OSTI)

    Yang, Xiaoli; Hofmann, Ralf; Dapp, Robin; van de Kamp, Thomas; Rolo, Tomy dos Santos; Xiao, Xianghui; Moosmann, Julian; Kashef, Jubin; Stotzka, Rainer

    2015-01-01

    High-resolution, three-dimensional (3D) imaging of soft tissues requires the solution of two inverse problems: phase retrieval and the reconstruction of the 3D image from a tomographic stack of two-dimensional (2D) projections. The number of projections per stack should be small to accommodate fast tomography of rapid processes and to constrain X-ray radiation dose to optimal levels to either increase the duration of in vivo time-lapse series at a given goal for spatial resolution and/or the conservation of structure under X-ray irradiation. In pursuing the 3D reconstruction problem in the sense of compressive sampling theory, we propose to reduce the number of projections by applying an advanced algebraic technique subject to the minimisation of the total variation (TV) in the reconstructed slice. This problem is formulated in a Lagrangian multiplier fashion with the parameter value determined by appealing to a discrete L-curve in conjunction with a conjugate gradient method. The usefulness of this reconstruction modality is demonstrated for simulated and in vivo data, the latter acquired in parallel-beam imaging experiments using synchrotron radiation. (C) 2015 Optical Society of America

  2. 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; Anchel, David J.; Gaudette, Glenn; Romanelli, Pantaleo; Hainfeld, James

    2010-06-29

    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.

  3. Solar X-ray physics

    SciTech Connect (OSTI)

    Bornmann, P.L. )

    1991-01-01

    Research on solar X-ray phenomena performed by American scientists during 1987-1990 is reviewed. Major topics discussed include solar images observed during quiescent times, the processes observed during solar flares, and the coronal, interplanetary, and terrestrial phenomena associated with solar X-ray flares. Particular attention is given to the hard X-ray emission observed at the start of the flare, the energy transfer to the soft X-ray emitting plasma, the late resolution of the flare as observed in soft X-ray, and the rate of occurrence of solar flares as a function of time and latitude. Pertinent aspects of nonflaring, coronal X-ray emission and stellar flares are also discussed. 175 refs.

  4. Miniature x-ray source

    DOE Patents [OSTI]

    Trebes, James E.; Stone, Gary F.; Bell, Perry M.; Robinson, Ronald B.; Chornenky, Victor I.

    2002-01-01

    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.

  5. Crystal defect studies using x-ray diffuse scattering

    SciTech Connect (OSTI)

    Larson, B.C.

    1980-01-01

    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.

  6. X-Ray Science Education

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

    TV Network external link DNA Interactive external link Reciprocal Net external link X-ray Science Courses and Programs Various educational efforts are closely related to the...

  7. Biological Imaging by Soft X-Ray Diffraction Microscopy

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

    methods (see previous highlight, "Demonstration of Coherent X-Ray Diffraction Imaging"). Experimental diffraction data used as input to the difference map algorithm....

  8. X-ray lithography using holographic images

    DOE Patents [OSTI]

    Howells, M.S.; Jacobsen, C.

    1997-03-18

    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.

  9. X-ray lithography using holographic images

    DOE Patents [OSTI]

    Howells, Malcolm S.; Jacobsen, Chris

    1997-01-01

    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.

  10. Coherent x-ray diffraction imaging of paint pigmentparticles by scanning a phase plate modulator

    SciTech Connect (OSTI)

    Chu Y. S.; Chen B.; Zhang F.; Berenguer F.; Bean R.; Kewish C.; Vila-Comamala J.; Rodenburg J.; Robinson I.

    2011-10-19

    We have implemented a coherent x-ray diffraction imaging technique that scans a phase plate to modulate wave-fronts of the x-ray beam transmitted by samples. The method was applied to measure a decorative alkyd paint containing iron oxide red pigment particles. By employing an iterative algorithm for wave-front modulation phase retrieval, we obtained an image of the paint sample that shows the distribution of the pigment particles and is consistent with the result obtained from a transmission x-ray microscope. The technique has been experimentally proven to be a feasible coherent x-ray imaging method with about 120 nm spatial resolution and was shown to work well with industrially relevant specimens.

  11. X-ray shearing interferometer

    DOE Patents [OSTI]

    Koch, Jeffrey A.

    2003-07-08

    An x-ray interferometer for analyzing high density plasmas and optically opaque materials includes a point-like x-ray source for providing a broadband x-ray source. The x-rays are directed through a target material and then are reflected by a high-quality ellipsoidally-bent imaging crystal to a diffraction grating disposed at 1.times. magnification. A spherically-bent imaging crystal is employed when the x-rays that are incident on the crystal surface are normal to that surface. The diffraction grating produces multiple beams which interfere with one another to produce an interference pattern which contains information about the target. A detector is disposed at the position of the image of the target produced by the interfering beams.

  12. A statistical, task-based evaluation method for three-dimensional x-ray breast imaging systems using variable-background phantoms

    SciTech Connect (OSTI)

    Park, Subok; Jennings, Robert; Liu Haimo; Badano, Aldo; Myers, Kyle

    2010-12-15

    Purpose: For the last few years, development and optimization of three-dimensional (3D) x-ray breast imaging systems, such as digital breast tomosynthesis (DBT) and computed tomography, have drawn much attention from the medical imaging community, either academia or industry. However, there is still much room for understanding how to best optimize and evaluate the devices over a large space of many different system parameters and geometries. Current evaluation methods, which work well for 2D systems, do not incorporate the depth information from the 3D imaging systems. Therefore, it is critical to develop a statistically sound evaluation method to investigate the usefulness of inclusion of depth and background-variability information into the assessment and optimization of the 3D systems. Methods: In this paper, we present a mathematical framework for a statistical assessment of planar and 3D x-ray breast imaging systems. Our method is based on statistical decision theory, in particular, making use of the ideal linear observer called the Hotelling observer. We also present a physical phantom that consists of spheres of different sizes and materials for producing an ensemble of randomly varying backgrounds to be imaged for a given patient class. Lastly, we demonstrate our evaluation method in comparing laboratory mammography and three-angle DBT systems for signal detection tasks using the phantom's projection data. We compare the variable phantom case to that of a phantom of the same dimensions filled with water, which we call the uniform phantom, based on the performance of the Hotelling observer as a function of signal size and intensity. Results: Detectability trends calculated using the variable and uniform phantom methods are different from each other for both mammography and DBT systems. Conclusions: Our results indicate that measuring the system's detection performance with consideration of background variability may lead to differences in system performance

  13. Ultra-short wavelength x-ray system

    DOE Patents [OSTI]

    Umstadter, Donald; He, Fei; Lau, Yue-Ying

    2008-01-22

    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. 14.05.14 RH Synchrotron X-ray - JCAP

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

    High-Throughput Synchrotron X-Ray Experimentation for Combinatorial Phase Matching Gregoire, J. M. et al. High-throughput synchrotron X-ray diffraction for combinatorial phase mapping. Journal of Synchrotron Radiation 21, 1262-1268, DOI: 10.1107/s1600577514016488 (2014). Scientific Achievement Development of new synchrotron X-ray diffraction and fluorescence methods for rapid characterization of material libraries. Significance & impact First demonstration of prototype facility capable of

  15. X-ray transmission movies of spontaneous dynamic events

    SciTech Connect (OSTI)

    Smilowitz, L.; Henson, B. F.; Holmes, M.; Novak, A.; Oschwald, D.; Dolgonos, P.; Qualls, B.

    2014-11-15

    We describe a new x-ray radiographic imaging system which allows for continuous x-ray transmission imaging of spontaneous dynamic events. We demonstrate this method on thermal explosions in three plastic bonded formulations of the energetic material octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine. We describe the x-ray imaging system and triggering developed to enable the continuous imaging of a thermal explosion.

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

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

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

    2015-03-14

    Accurate measurement of the fat-to-muscle ratio in animal model is important for obesity research. In addition, 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 inmore » the fat to muscle ratio could be observed with the x-ray dose of 0.001 mGy.« less

  17. Towards phasing using high X-ray intensity

    SciTech Connect (OSTI)

    Galli, Lorenzo; Son, Sang-Kil; Barends, Thomas R. M.; White, Thomas A.; Barty, Anton; Botha, Sabine; Boutet, Sébastien; Caleman, Carl; Doak, R. Bruce; Nanao, Max H.; Nass, Karol; Shoeman, Robert L.; Timneanu, Nicusor; Santra, Robin; Schlichting, Ilme; Chapman, Henry N.

    2015-09-30

    X-ray free-electron lasers (XFELs) show great promise for macromolecular structure determination from sub-micrometre-sized crystals, using the emerging method of serial femtosecond crystallography. The extreme brightness of the XFEL radiation can multiply ionize most, if not all, atoms in a protein, causing their scattering factors to change during the pulse, with a preferential `bleaching' of heavy atoms. This paper investigates the effects of electronic damage on experimental data collected from a Gd derivative of lysozyme microcrystals at different X-ray intensities, and the degree of ionization of Gd atoms is quantified from phased difference Fourier maps. A pattern sorting scheme is proposed to maximize the ionization contrast and the way in which the local electronic damage can be used for a new experimental phasing method is discussed.

  18. Towards phasing using high X-ray intensity

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

    Galli, Lorenzo; Son, Sang -Kil; Barends, Thomas R. M.; White, Thomas A.; Barty, Anton; Botha, Sabine; Boutet, Sébastien; Caleman, Carl; Doak, R. Bruce; Nanao, Max H.; et al

    2015-09-30

    X-ray free-electron lasers (XFELs) show great promise for macromolecular structure determination from sub-micrometre-sized crystals, using the emerging method of serial femtosecond crystallography. The extreme brightness of the XFEL radiation can multiply ionize most, if not all, atoms in a protein, causing their scattering factors to change during the pulse, with a preferential `bleaching' of heavy atoms. This paper investigates the effects of electronic damage on experimental data collected from a Gd derivative of lysozyme microcrystals at different X-ray intensities, and the degree of ionization of Gd atoms is quantified from phased difference Fourier maps. In conclusion, a pattern sorting schememore » is proposed to maximize the ionization contrast and the way in which the local electronic damage can be used for a new experimental phasing method is discussed.« less

  19. Towards phasing using high X-ray intensity

    SciTech Connect (OSTI)

    Galli, Lorenzo; Son, Sang -Kil; Barends, Thomas R. M.; White, Thomas A.; Barty, Anton; Botha, Sabine; Boutet, Sébastien; Caleman, Carl; Doak, R. Bruce; Nanao, Max H.; Nass, Karol; Shoeman, Robert L.; Timneanu, Nicusor; Santra, Robin; Schlichting, Ilme; Chapman, Henry N.

    2015-09-30

    X-ray free-electron lasers (XFELs) show great promise for macromolecular structure determination from sub-micrometre-sized crystals, using the emerging method of serial femtosecond crystallography. The extreme brightness of the XFEL radiation can multiply ionize most, if not all, atoms in a protein, causing their scattering factors to change during the pulse, with a preferential `bleaching' of heavy atoms. This paper investigates the effects of electronic damage on experimental data collected from a Gd derivative of lysozyme microcrystals at different X-ray intensities, and the degree of ionization of Gd atoms is quantified from phased difference Fourier maps. In conclusion, a pattern sorting scheme is proposed to maximize the ionization contrast and the way in which the local electronic damage can be used for a new experimental phasing method is discussed.

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

    DOE Patents [OSTI]

    Warburton, William K.; Zhou, Zhiquing

    1999-01-01

    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.

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

    DOE Patents [OSTI]

    Warburton, W.K.

    1999-02-16

    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.

  2. Miniature x-ray source

    DOE Patents [OSTI]

    Trebes, James E.; Bell, Perry M.; Robinson, Ronald B.

    2000-01-01

    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.

  3. X-Ray Interactions with Matter from the Center for X-Ray Optics...

    Office of Scientific and Technical Information (OSTI)

    X-Ray Interactions with Matter from the Center for X-Ray Optics (CXRO) Title: X-Ray Interactions with Matter from the Center for X-Ray Optics (CXRO) The primary interactions of ...

  4. 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.

    1999-06-15

    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.

  5. X-ray compass for determining device orientation

    DOE Patents [OSTI]

    Da Silva, Luiz B.; Matthews, Dennis L.; Fitch, Joseph P.; Everett, Matthew J.; Colston, Billy W.; Stone, Gary F.

    1999-01-01

    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.

  6. Electromechanical x-ray generator

    DOE Patents [OSTI]

    Watson, Scott A; Platts, David; Sorensen, Eric B

    2016-05-03

    An electro-mechanical x-ray generator configured to obtain high-energy operation with favorable energy-weight scaling. The electro-mechanical x-ray generator may include a pair of capacitor plates. The capacitor plates may be charged to a predefined voltage and may be separated to generate higher voltages on the order of hundreds of kV in the AK gap. The high voltage may be generated in a vacuum tube.

  7. Femtosecond X-ray protein nanocrystallography

    SciTech Connect (OSTI)

    Chapman, Henry N.; Barty, Anton; White, Thomas A.; Aquila, Andrew; Schulz, Joachim; DePonte, Daniel P.; Martin, Andrew V.; Coppola, Nicola; Liang, Mengning; Caleman, Carl; Gumprecht, Lars; Stern, Stephan; Nass, Karol; Fromme, Petra; Hunter, Mark S.; Grotjohann, Ingo; Fromme, Raimund; Kirian, Richard A.; Weierstall, Uwe; Doak, R. Bruce; Schmidt, Kevin E.; Wang, Xiaoyu; Spence, John C. H.; Schlichting, Ilme; Epp, Sascha W.; Rolles, Daniel; Rudenko, Artem; Foucar, Lutz; Rudek, Benedikt; Erk, Benjamin; Schmidt, Carlo; Hömke, André; Strüder, Lothar; Ullrich, Joachim; Krasniqi, Faton; Lomb, Lukas; Shoeman, Robert L.; Bott, Mario; Barends, Thomas R. M.; Kuhnel, Kai-Uwe; Schroter, Claus-Dieter; Hartmann, Robert; Holl, Peter; Reich, Christian; Soltau, Heike; Kimmel, Nils; Weidenspointner, Georg; Pietschner, Daniel; Hauser, Günter; Herrmann, Sven; Schaller, Gerhard; Schopper, Florian; Andritschke, Robert; Boutet, Sébastien; Krzywinski, Jacek; Bostedt, Christoph; Messerschmidt, Marc; Bozek, John D.; Williams, Garth J.; Bogan, Michael J.; Hampton, Christina Y.; Sierra, Raymond G.; Starodub, Dmitri; Gorke, Hubert; Hau-Riege, Stefan P.; Frank, Matthias; Maia, Filipe R. N. C.; Hajdu, Janos; Timneanu, Nicusor; Seibert, M. Marvin; Andreasson, Jakob; Rocker, Andrea; Jönsson, Olof; Svenda, Martin; Holton, James M.; Marchesini, Stefano; Neutze, Richard; Schorb, Sebastian; Rupp, Daniela; Adolph, Marcus; Gorkhover, Tais; Andersson, Inger; Barthelmess, Miriam; Bajt, Saša; Hirsemann, Helmut; Potdevin, Guillaume; Graafsma, Heinz; Nilsson, Björn

    2011-02-03

    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 μm 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.

  8. In-situ energy dispersive x-ray diffraction study of the growth of CuO nanowires by annealing method

    SciTech Connect (OSTI)

    Srivastava, Himanshu; Ganguli, Tapas; Deb, S. K.; Sant, Tushar; Poswal, H. K.; Sharma, Surinder M.

    2013-10-14

    The in-situ growth of CuO nanowires was studied by Energy Dispersive X-ray Diffraction (EDXRD) to observe the mechanism of growth. The study was carried out for comparison at two temperaturesat 500 C, the optimum temperature of the nanowires growth, and at 300 C just below the temperature range of the growth. The in situ observation revealed the successive oxidation of Cu foil to Cu{sub 2}O layer and finally to CuO layer. Further analysis showed the presence of a compressive stress in CuO layer due to interface at CuO and Cu{sub 2}O layers. The compressive stress was found to increase with the growth of the nanowires at 500 C while it relaxed with the growth of CuO layer at 300 C. The present results do not support the existing model of stress relaxation induced growth of nanowires. Based on the detailed Transmission Electron Microscope, Scanning Electron Microscope, and EDXRD results, a microstructure based growth model has been suggested.

  9. 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

    2011-07-15

    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

  10. SMB, X-ray Absorption Spectroscopy

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

    Absorption Spectroscopy X-ray Absorption Spectroscopy X-ray absorption spectroscopy (XAS) is a well-established technique for simultaneous local geometric and electronic structure...

  11. 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.; Matthews, Dennis L.

    1991-01-01

    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.

  12. Multiple wavelength X-ray monochromators

    DOE Patents [OSTI]

    Steinmeyer, P.A.

    1992-11-17

    An improved apparatus and method is provided for separating input x-ray radiation containing first and second x-ray wavelengths into spatially separate first and second output radiation which contain the first and second x-ray wavelengths, respectively. The apparatus includes a crystalline diffractor which includes a first set of parallel crystal planes, where each of the planes is spaced a predetermined first distance from one another. The crystalline diffractor also includes a second set of parallel crystal planes inclined at an angle with respect to the first set of crystal planes where each of the planes of the second set of parallel crystal planes is spaced a predetermined second distance from one another. In one embodiment, the crystalline diffractor is comprised of a single crystal. In a second embodiment, the crystalline diffractor is comprised of a stack of two crystals. In a third embodiment, the crystalline diffractor includes a single crystal that is bent for focusing the separate first and second output x-ray radiation wavelengths into separate focal points. 3 figs.

  13. Multiple wavelength X-ray monochromators

    DOE Patents [OSTI]

    Steinmeyer, Peter A.

    1992-11-17

    An improved apparatus and method is provided for separating input x-ray radiation containing first and second x-ray wavelengths into spatially separate first and second output radiation which contain the first and second x-ray wavelengths, respectively. The apparatus includes a crystalline diffractor which includes a first set of parallel crystal planes, where each of the planes is spaced a predetermined first distance from one another. The crystalline diffractor also includes a second set of parallel crystal planes inclined at an angle with respect to the first set of crystal planes where each of the planes of the second set of parallel crystal planes is spaced a predetermined second distance from one another. In one embodiment, the crystalline diffractor is comprised of a single crystal. In a second embodiment, the crystalline diffractor is comprised of a stack of two crystals. In a third embodiment, the crystalline diffractor includes a single crystal that is bent for focussing the separate first and second output x-ray radiation wavelengths into separate focal points.

  14. 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

    2012-11-21

    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.

  15. High resolution energy-sensitive digital X-ray

    DOE Patents [OSTI]

    Nygren, David R.

    1995-01-01

    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.

  16. High resolution energy-sensitive digital X-ray

    DOE Patents [OSTI]

    Nygren, D.R.

    1995-07-18

    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 detector such that each one of the 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. 5 figs.

  17. Noise variance analysis using a flat panel x-ray detector: A method for additive noise assessment with application to breast CT applications

    SciTech Connect (OSTI)

    Yang Kai; Huang, Shih-Ying; Packard, Nathan J.; Boone, John M.

    2010-07-15

    Purpose: A simplified linear model approach was proposed to accurately model the response of a flat panel detector used for breast CT (bCT). Methods: Individual detector pixel mean and variance were measured from bCT projection images acquired both in air and with a polyethylene cylinder, with the detector operating in both fixed low gain and dynamic gain mode. Once the coefficients of the linear model are determined, the fractional additive noise can be used as a quantitative metric to evaluate the system's efficiency in utilizing x-ray photons, including the performance of different gain modes of the detector. Results: Fractional additive noise increases as the object thickness increases or as the radiation dose to the detector decreases. For bCT scan techniques on the UC Davis prototype scanner (80 kVp, 500 views total, 30 frames/s), in the low gain mode, additive noise contributes 21% of the total pixel noise variance for a 10 cm object and 44% for a 17 cm object. With the dynamic gain mode, additive noise only represents approximately 2.6% of the total pixel noise variance for a 10 cm object and 7.3% for a 17 cm object. Conclusions: The existence of the signal-independent additive noise is the primary cause for a quadratic relationship between bCT noise variance and the inverse of radiation dose at the detector. With the knowledge of the additive noise contribution to experimentally acquired images, system modifications can be made to reduce the impact of additive noise and improve the quantum noise efficiency of the bCT system.

  18. Compact x-ray source and panel

    DOE Patents [OSTI]

    Sampayon, Stephen E.

    2008-02-12

    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.

  19. Focused X-ray source

    DOE Patents [OSTI]

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

    1990-08-21

    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.

  20. Focused X-ray source

    DOE Patents [OSTI]

    Piestrup, Melvin A.; Boyers, David G.; Pincus, Cary I.; Maccagno, Pierre

    1990-01-01

    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.

  1. Synchrotron x-Ray Spectroscopic Analysis (Book) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Book: Synchrotron x-Ray Spectroscopic Analysis Citation Details In-Document Search Title: Synchrotron x-Ray Spectroscopic Analysis Authors: Sutton, S.R. ; Newville, M. 1 + Show ...

  2. X-ray absorption fine-structure spectroscopy (Book) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    X-ray absorption fine-structure spectroscopy Citation Details In-Document Search Title: X-ray absorption fine-structure spectroscopy Authors: Newville, M. 1 + Show Author ...

  3. X-ray radiography for container inspection

    DOE Patents [OSTI]

    Katz, Jonathan I.; Morris, Christopher L.

    2011-06-07

    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.

  4. Hard x-ray delay line for x-ray photon correlation spectroscopy...

    Office of Scientific and Technical Information (OSTI)

    Hard x-ray delay line for x-ray photon correlation spectroscopy and jitter-free pump-probe experiments at LCLS Citation Details In-Document Search Title: Hard x-ray delay line for...

  5. A computational study of x-ray emission from high-Z x-ray sources...

    Office of Scientific and Technical Information (OSTI)

    A computational study of x-ray emission from high-Z x-ray sources on the National Ignition Facility laser Citation Details In-Document Search Title: A computational study of x-ray ...

  6. Reabsorption of Soft X-Ray Emission at High X-Ray Free-Electron...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Reabsorption of Soft X-Ray Emission at High X-Ray Free-Electron Laser Fluences Citation Details In-Document Search Title: Reabsorption of Soft X-Ray Emission at ...

  7. Femtosecond X-ray Absorption Spectroscopy at a Hard X-ray Free...

    Office of Scientific and Technical Information (OSTI)

    Femtosecond X-ray Absorption Spectroscopy at a Hard X-ray Free Electron Laser: Application to Spin Crossover Dynamics Citation Details In-Document Search Title: Femtosecond X-ray...

  8. A computational study of x-ray emission from high-Z x-ray sources...

    Office of Scientific and Technical Information (OSTI)

    study of x-ray emission from high-Z x-ray sources on the National Ignition Facility laser Citation Details In-Document Search Title: A computational study of x-ray emission...

  9. X-Ray Diffraction Microscopy of Magnetic Structures

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

    This method can be used at any coherent light source, such as x-ray free-electron lasers, where ultra-short pulses would freeze-frame magnetic changes, offering the potential for ...

  10. 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

    2013-07-01

    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.

  11. Femtosecond Time-Delay X-ray Holography

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

    optics to the X-ray regime, such as holography, interferometry, and laser-based imaging. ... Those experiments showed that no damage occurred during the 30 fs duration pulse. However, ...

  12. X-ray photonic microsystems for the manipulation of synchrotron...

    Office of Scientific and Technical Information (OSTI)

    massive size of the silicon single-crystal optics currently used. Here we show that micromechanical systems can be used as X-ray optics to create and preserve the spatial, ...

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

    SciTech Connect (OSTI)

    Guo, J.-H.

    2005-07-30

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

  14. An image focusing means by using an opaque object to diffract x-rays

    DOE Patents [OSTI]

    Sommargren, Gary E.; Weaver, H. Joseph

    1991-01-01

    The invention provides a method and apparatus for focusing and imaging x-rays. An opaque sphere is used as a diffractive imaging element to diffract x-rays from an object so that the divergent x-ray wavefronts are transformed into convergent wavefronts and are brought to focus to form an image of the object with a large depth of field.

  15. Microgap x-ray detector

    DOE Patents [OSTI]

    Wuest, Craig R.; Bionta, Richard M.; Ables, Elden

    1994-01-01

    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.

  16. Microgap x-ray detector

    DOE Patents [OSTI]

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

    1994-05-03

    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.

  17. NEW X-RAY DETECTIONS OF WNL STARS

    SciTech Connect (OSTI)

    Skinner, Stephen L.; Zhekov, Svetozar A.; Guedel, Manuel; Schmutz, Werner; Sokal, Kimberly R.

    2012-05-15

    Previous studies have demonstrated that putatively single nitrogen-type Wolf-Rayet stars (WN stars) without known companions are X-ray sources. However, almost all WN star X-ray detections so far have been of earlier WN2-WN6 spectral subtypes. Later WN7-WN9 subtypes (also known as WNL stars) have proved more difficult to detect, an important exception being WR 79a (WN9ha). We present here new X-ray detections of the WNL stars WR 16 (WN8h) and WR 78 (WN7h). These new results, when combined with previous detections, demonstrate that X-ray emission is present in WN stars across the full range of spectral types, including later WNL stars. The two WN8 stars observed to date (WR 16 and WR 40) show unusually low X-ray luminosities (L{sub x} ) compared to other WN stars, and it is noteworthy that they also have the lowest terminal wind speeds (v{sub {infinity}}). Existing X-ray detections of about a dozen WN stars reveal a trend of increasing L{sub x} with wind luminosity L{sub wind} = (1/2)M-dot v{sup 2}{sub {infinity}}, suggesting that wind kinetic energy may play a key role in establishing X-ray luminosity levels in WN stars.

  18. Study of runaway electrons using dosimetry of hard x-ray radiations in Damavand tokamak

    SciTech Connect (OSTI)

    Rasouli, C.; Pourshahab, B.; Rasouli, H.; Hosseini Pooya, S. M.; Orouji, T.

    2014-05-15

    In this work several studies have been conducted on hard x-ray emissions of Damavand tokamak based on radiation dosimetry using the Thermoluminescence method. The goal was to understand interactions of runaway electrons with plasma particles, vessel wall, and plasma facing components. Total of 354 GR-200 (LiF:Mg,Cu,P) thermoluminescence dosimeter (TLD) crystals have been placed on 118 points – three TLDs per point – to map hard x-ray radiation doses on the exterior of the vacuum vessel. Results show two distinctive levels of x-ray radiations doses on the exterior of the vessel. The low-dose area on which measured dose is about 0.5 mSv/shot. In the low-dose area there is no particular component inside the vessel. On the contrary, on high-dose area of the vessel, x-ray radiations dose exceeds 30 mSv/shot. The high-dose area coincides with the position of limiters, magnetic probe ducts, and vacuum vessel intersections. Among the high-dose areas, the highest level of dose is measured in the position of the limiter, which could be due to its direct contact with the plasma column and with runaway electrons. Direct collisions of runaway electrons with the vessel wall and plasma facing components make a major contribution for production of hard x-ray photons in Damavand tokamak.

  19. X-ray standing wave analysis of nanostructures using partially coherent radiation

    SciTech Connect (OSTI)

    Tiwari, M. K. Das, Gangadhar; Bedzyk, M. J.

    2015-09-07

    The effect of longitudinal (or temporal) coherence on total reflection assisted x-ray standing wave (TR-XSW) analysis of nanoscale materials is quantitatively demonstrated by showing how the XSW fringe visibility can be strongly damped by decreasing the spectral resolution of the incident x-ray beam. The correction for nonzero wavelength dispersion (δλ ≠ 0) of the incident x-ray wave field is accounted for in the model computations of TR-XSW assisted angle dependent fluorescence yields of the nanostructure coatings on x-ray mirror surfaces. Given examples include 90 nm diameter Au nanospheres deposited on a Si(100) surface and a 3 nm thick Zn layer trapped on top a 100 nm Langmuir-Blodgett film coating on a Au mirror surface. Present method opens up important applications, such as enabling XSW studies of large dimensioned nanostructures using conventional laboratory based partially coherent x-ray sources.

  20. Crystallization and preliminary X-ray diffraction study of porcine carboxypeptidase B

    SciTech Connect (OSTI)

    Akparov, V. Kh.; Timofeev, V. I. Kuranova, I. P.

    2015-05-15

    Crystals of porcine pancreatic carboxypeptidase B have been grown in microgravity by the capillary counter-diffusion method through a gel layer. The X-ray diffraction study showed that the crystals belong to sp. gr. P4{sub 1}2{sub 1}2 and have the following unit-cell parameters: a = b = 79.58 Å, c = 100.51 Å; α = β = γ = 90.00°. The X-ray diffraction data set suitable for the determination of the three-dimensional structure at atomic resolution was collected from one of the grown crystals at the SPring 8 synchrotron facility to 0.98 Å resolution.

  1. 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 ... wavelengths relevant to atomic and molecular phenomena) with the advantages of ...

  2. Producing X-rays at the APS

    ScienceCinema (OSTI)

    None

    2013-04-19

    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.

  3. Lensless X-Ray Imaging in Reflection

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

    Lensless 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 combine the advantages of sychrotron light sources (high brightness and x-ray wavelengths relevant to atomic and molecular phenomena) with the advantages of visible-light lasers (highly coherent beams). All of these characteristics are important for coherent x-ray diffraction imaging-lensless imaging

  4. Lensless X-Ray Imaging in Reflection

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

    Lensless 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 combine the advantages of sychrotron light sources (high brightness and x-ray wavelengths relevant to atomic and molecular phenomena) with the advantages of visible-light lasers (highly coherent beams). All of these characteristics are important for coherent x-ray diffraction imaging-lensless imaging

  5. Lensless X-Ray Imaging in Reflection

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

    Lensless 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 combine the advantages of sychrotron light sources (high brightness and x-ray wavelengths relevant to atomic and molecular phenomena) with the advantages of visible-light lasers (highly coherent beams). All of these characteristics are important for coherent x-ray diffraction imaging-lensless imaging

  6. Lensless X-Ray Imaging in Reflection

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

    Lensless 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 combine the advantages of sychrotron light sources (high brightness and x-ray wavelengths relevant to atomic and molecular phenomena) with the advantages of visible-light lasers (highly coherent beams). All of these characteristics are important for coherent x-ray diffraction imaging-lensless imaging

  7. Neutron and X-ray Scattering

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

    Neutron and X-ray Scattering Neutron and X-ray Scattering When used together, neutrons and high-energy x-rays provide a supremely powerful scientific tool for mining details about the structure of materials. Combining neutrons and high-energy x-rays to explore the frontiers of materials in extreme environments. Illuminating previously inaccessible time and spatial scales. Enabling in situ research to design, discover, and control materials. Get Expertise Donald Brown Email Pushing the limits of

  8. Phase-sensitive X-ray imager

    DOE Patents [OSTI]

    Baker, Kevin Louis

    2013-01-08

    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.

  9. Cryotomography x-ray microscopy state

    DOE Patents [OSTI]

    Le Gros, Mark; Larabell, Carolyn A.

    2010-10-26

    An x-ray microscope stage enables alignment of a sample about a rotation axis to enable three dimensional tomographic imaging of the sample using an x-ray microscope. A heat exchanger assembly provides cooled gas to a sample during x-ray microscopic imaging.

  10. NREL: Measurements and Characterization - X-Ray and UV Photoelectron

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

    Spectroscopy X-Ray and UV Photoelectron Spectroscopy Example of graph made with cluster tool; plots counts (Y-axis) vs. binding energy (X-axis) for PET Carbon 1S. High-resolution XPS spectra of carbon 1s from polyethylene terephthalate backsheet material, showing excellent quantitative agreement between measured and predicted peak area ratios. Subtle differences in polymer functionality are assessed by deviations from stoichiometry. In photoemission techniques, we use either X-rays or

  11. High performance x-ray anti-scatter grid

    DOE Patents [OSTI]

    Logan, Clinton M.

    1995-01-01

    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.

  12. High performance x-ray anti-scatter grid

    DOE Patents [OSTI]

    Logan, C.M.

    1995-05-23

    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.

  13. X-Ray Microscopy | Argonne National Laboratory

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

    X-Ray Microscopy X-Ray Microscopy This group exploits the unique capabilities of hard X-ray microscopy to visualize and understand the structure and behavior of hybrid, energy-related, and tailored nanomaterials The Hard X-Ray Nanoprobe, located at Sector 26 of the Advanced Photon Source (APS) and operated by our group and APS, is the only dedicated X-ray microscopy beamline within the portfolios of the nation's Nanoscale Science Research Centers. Our scientific program seeks to understand

  14. X-ray transmissive debris shield

    DOE Patents [OSTI]

    Spielman, Rick B.

    1996-01-01

    An X-ray debris shield for use in X-ray lithography that is comprised of an X-ray window having a layer of low density foam exhibits increased longevity without a substantial increase in exposure time. The low density foam layer serves to absorb the debris emitted from the X-ray source and attenuate the shock to the window so as to reduce the chance of breakage. Because the foam is low density, the X-rays are hardly attenuated by the foam and thus the exposure time is not substantially increased.

  15. X-ray transmissive debris shield

    DOE Patents [OSTI]

    Spielman, R.B.

    1996-05-21

    An X-ray debris shield for use in X-ray lithography that is comprised of an X-ray window having a layer of low density foam exhibits increased longevity without a substantial increase in exposure time. The low density foam layer serves to absorb the debris emitted from the X-ray source and attenuate the shock to the window so as to reduce the chance of breakage. Because the foam is low density, the X-rays are hardly attenuated by the foam and thus the exposure time is not substantially increased.

  16. X-rays from a microsecond X-pinch

    SciTech Connect (OSTI)

    Appartaim, R. K.

    2013-08-28

    The characteristics of x-rays emitted by X-pinches driven by discharging a current of ∼320 kA with a quarter period of 1 μs in crossed 25 μm wires have been investigated. The x-ray emissions are studied using filtered silicon photodiodes, diamond radiation detectors, and pinhole cameras. The results show that predominantly x-rays from the microsecond X-pinch tend to be emitted in two distinct sets of bursts. The first is predominantly “soft,” i.e., with photon energy hν < 5 keV, followed by a second set of bursts beginning up to 100 ns following the initial bursts, and usually consisting of higher photon energies. Our results show, however, that the x-ray emissions do not contain a significant component with hν > 10 keV as might be expected from electron beam activity within the plasma or from the X-pinch diode. High-resolution images obtained with the observed x-rays suggest a well-defined small source of soft x-rays that demonstrates the potential of the microsecond X-pinch.

  17. Digital X-ray Pipe Inspector Software

    Energy Science and Technology Software Center (OSTI)

    2009-10-29

    The Digital X-ray Pipe Inspector software requires a digital x-ray image of a pipe as input to the program, such as the image in Attachment A Figure 1. The image may be in a variety of software formats such as bitmap, jpeg, tiff, DICOM or DICONDE. The software allows the user to interactively select a region of interest from the image for analysis. This software is used to analyze digital x-ray images of pipes tomore » evaluate loss of wall thickness. The software specifically provides tools to analyze the image in (a) the pipe walls, (b) between the pipe walls. Traditional software uses only the information at the pipe wall while this new software also evaluates the image between the pipewalls. This makes the inspection process faster, more thorough, more efficient, and reduces expensive reshots. Attachment A Figure 2 shows a region of interest (a green box) drawn by the user around an anomaly in the pipe wall. This area is automatically analyzed by the external pipe wall tool with the result shown in Attachment A Figure 3. The edges of the pipe wall are detected and highlighted in yellow and areas where the wall thickness in less the the minimum wall threshold are shown in red. These measurements are typically made manually in other software programs, which lead to errors and inconsistency because the location of the edges are estimated by the user. Attachment A Figure 4 shows a region of interest (a green box) drawn by the user between the pipe walls. As can be seen there are intensity anomalies that correspond to wall defects. However, this information is not used directly by other software programs. In order to fully investigate these anomalies, the pipe would be reinspected in a different orientation to attempt to obtain a view of the anomaly in the pipe wall rather than the interior of the pipe. The pipe may need to be x-rayed a number of times to obtain the correct orientation. This is very costly and time consuming. The new software can perform the

  18. Intermolecular triple proton and deuteron transfer in crystalline 3,5-dimethylpyrazole studied by NMR, NQR, and x-ray methods

    SciTech Connect (OSTI)

    Wehrle, B.; Aguilar-Parrilla, F.; Limbach, H.H. ); de la Concepcion Foces-Foces, M.; Cano, F.H. ); Elguero, J. ); Baldy, A.; Pierrot, M. ); Khurshid, M.M.T.; Larcombe-McDouall, J.B.; Smith, J.A.S. )

    1989-09-13

    A combination of {sup 13}C, {sup 15}N magnetic resonance, {sup 14}N quadrupole double resonance, and x-ray studies of solid 3,5-dimethylpyrazole between 270 and 350 K has shown that the NH...N hydrogen bond units present in the crystal are dynamically disordered, so that each nitrogen atom is on average attached to half a hydrogen atom. The molecules form discrete hydrogen-bonded cyclic trimers, in which the hydrogen atoms move in a double minimum potential energy surface which is symmetrical, to within experimental error. The experimental evidence in this temperature range is consistent with disorder by means of correlated triple hydrogen jumps with an activation energy of 45 kJ mol{sup {minus}1}. There is a large kinetic hydrogen (HHH)/deuterium (DDD) isotope effort of >20 at 299 K and equal to 8 at 347 K.

  19. Dose optimization in cardiac x-ray imaging

    SciTech Connect (OSTI)

    Gislason-Lee, Amber J.; McMillan, Catherine; Cowen, Arnold R.; Davies, Andrew G.

    2013-09-15

    Purpose: The aim of this research was to optimize x-ray image quality to dose ratios in the cardiac catheterization laboratory. This study examined independently the effects of peak x-ray tube voltage (kVp), copper (Cu), and gadolinium (Gd) x-ray beam filtration on the image quality to radiation dose balance for adult patient sizes.Methods: Image sequences of polymethyl methacrylate (PMMA) phantoms representing two adult patient sizes were captured using a modern flat panel detector based x-ray imaging system. Tin and copper test details were used to simulate iodine-based contrast medium and stents/guide wires respectively, which are used in clinical procedures. Noise measurement for a flat field image and test detail contrast were used to calculate the contrast to noise ratio (CNR). Entrance surface dose (ESD) and effective dose measurements were obtained to calculate the figure of merit (FOM), CNR{sup 2}/dose. This FOM determined the dose efficiency of x-ray spectra investigated. Images were captured with 0.0, 0.1, 0.25, 0.4, and 0.9 mm Cu filtration and with a range of gadolinium oxysulphide (Gd{sub 2}O{sub 2}S) filtration.Results: Optimum x-ray spectra were the same for the tin and copper test details. Lower peak tube voltages were generally favored. For the 20 cm phantom, using 2 Lanex Fast Back Gd{sub 2}O{sub 2}S screens as x-ray filtration at 65 kVp provided the highest FOM considering ESD and effective dose. Considering ESD, this FOM was only marginally larger than that from using 0.4 mm Cu at 65 kVp. For the 30 cm phantom, using 0.25 mm copper filtration at 80 kVp was most optimal; considering effective dose the FOM was highest with no filtration at 65 kVp.Conclusions: These settings, adjusted for x-ray tube loading limits and clinically acceptable image quality, should provide a useful option for optimizing patient dose to image quality in cardiac x-ray imaging. The same optimal x-ray beam spectra were found for both the tin and copper details, suggesting

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

    SciTech Connect (OSTI)

    Zholents, A.; Accelerator Systems Division

    2010-09-30

    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.

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

    SciTech Connect (OSTI)

    Ren, Liqiang; Wu, Di; Li, Yuhua; Liu, Hong; Wang, Ge; Wu, Xizeng

    2014-03-15

    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 α} fluorescence x-rays (65.99 –69.80 keV) acquired after background subtraction are well calibrated, and finally the unattenuated K{sub α} 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 α} 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

  2. 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

    2010-08-02

    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.

  3. X-ray metrology and performance of a 45-cm long x-ray deformable mirror

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

    Poyneer, Lisa A.; Brejnholt, Nicolai F.; Hill, Randall; Jackson, Jessie; Hagler, Lisle; Celestre, Richard; Feng, Jun

    2016-05-20

    We describe experiments with a 45-cm long x-ray deformable mirror (XDM) that have been conducted in End Station 2, Beamline 5.3.1 at the Advanced Light Source. A detailed description of the hardware implementation is provided. We explain our one-dimensional Fresnel propagation code that correctly handles grazing incidence and includes a model of the XDM. This code is used to simulate and verify experimental results. Initial long trace profiler metrology of the XDM at 7.5 keV is presented. The ability to measure a large (150-nm amplitude) height change on the XDM is demonstrated. The results agree well with the simulated experimentmore » at an error level of 1 μrad RMS. Lastly, direct imaging of the x-ray beam also shows the expected change in intensity profile at the detector.« less

  4. Direct detection of x-rays for protein crystallography employing a thick, large area CCD

    DOE Patents [OSTI]

    Atac, Muzaffer; McKay, Timothy

    1999-01-01

    An apparatus and method for directly determining the crystalline structure of a protein crystal. The crystal is irradiated by a finely collimated x-ray beam. The interaction of the x-ray beam with the crystal produces scattered x-rays. These scattered x-rays are detected by means of a large area, thick CCD which is capable of measuring a significant number of scattered x-rays which impact its surface. The CCD is capable of detecting the position of impact of the scattered x-ray on the surface of the CCD and the quantity of scattered x-rays which impact the same cell or pixel. This data is then processed in real-time and the processed data is outputted to produce a image of the structure of the crystal. If this crystal is a protein the molecular structure of the protein can be determined from the data received.

  5. Femtosecond x-ray absorption spectroscopy with hard x-ray free electron laser

    SciTech Connect (OSTI)

    Katayama, Tetsuo; Togashi, Tadashi; Tono, Kensuke; Kameshima, Takashi; Inubushi, Yuichi; Sato, Takahiro; Hatsui, Takaki; Yabashi, Makina; Obara, Yuki; Misawa, Kazuhiko; Bhattacharya, Atanu; Kurahashi, Naoya; Ogi, Yoshihiro; Suzuki, Toshinori; Molecular Reaction Dynamics Research Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako 351-0198

    2013-09-23

    We have developed a method of dispersive x-ray absorption spectroscopy with a hard x-ray free electron laser (XFEL), generated by a self-amplified spontaneous emission (SASE) mechanism. A transmission grating was utilized for splitting SASE-XFEL light, which has a relatively large bandwidth (ΔE/E ∼ 5 × 10{sup −3}), into several branches. Two primary split beams were introduced into a dispersive spectrometer for measuring signal and reference spectra simultaneously. After normalization, we obtained a Zn K-edge absorption spectrum with a photon-energy range of 210 eV, which is in excellent agreement with that measured by a conventional wavelength-scanning method. From the analysis of the difference spectra, the noise ratio was evaluated to be ∼3 × 10{sup −3}, which is sufficiently small to trace minute changes in transient spectra induced by an ultrafast optical laser. This scheme enables us to perform single-shot, high-accuracy x-ray absorption spectroscopy with femtosecond time resolution.

  6. A high-transparency, micro-patternable chip for X-ray diffraction analysis of microcrystals under native growth conditions

    SciTech Connect (OSTI)

    Murray, Thomas D.; Lyubimov, Artem Y.; Ogata, Craig M.; Vo, Huy; Uervirojnangkoorn, Monarin; Brunger, Axel T.; Berger, James M.

    2015-08-11

    Microcrystals present a significant impediment to the determination of macromolecular structures by X-ray diffraction methods. Although microfocus synchrotron beamlines and X-ray free-electron lasers (XFELs) can enable the collection of interpretable diffraction data from microcrystals, there is a need for efficient methods of harvesting small volumes (<2 l) of microcrystals grown under common laboratory formats and delivering them to an X-ray beam source under native growth conditions. One approach that shows promise in overcoming the challenges intrinsic to microcrystal analysis is to pair so-called `fixed-target' sample-delivery devices with microbeam-based X-ray diffraction methods. However, to record weak diffraction patterns it is necessary to fabricate devices from X-ray-transparent materials that minimize background scattering. Presented here is the design of a new micro-diffraction device consisting of three layers fabricated from silicon nitride, photoresist and polyimide film. The chip features low X-ray scattering and X-ray absorption properties, and uses a customizable blend of hydrophobic and hydrophilic surface patterns to help localize microcrystals to defined regions. Microcrystals in their native growth conditions can be loaded into the chips with a standard pipette, allowing data collection at room temperature. Diffraction data collected from hen egg-white lysozyme microcrystals (1015 m) loaded into the chips yielded a complete, high-resolution (<1.6 ) data set sufficient to determine a high-quality structure by molecular replacement. In addition, the features of the chip allow the rapid and user-friendly analysis of microcrystals grown under virtually any laboratory format at microfocus synchrotron beamlines and XFELs.

  7. A high-transparency, micro-patternable chip for X-ray diffraction analysis of microcrystals under native growth conditions

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

    Murray, Thomas D.; Lyubimov, Artem Y.; Ogata, Craig M.; Vo, Huy; Uervirojnangkoorn, Monarin; Brunger, Axel T.; Berger, James M.

    2015-08-11

    Microcrystals present a significant impediment to the determination of macromolecular structures by X-ray diffraction methods. Although microfocus synchrotron beamlines and X-ray free-electron lasers (XFELs) can enable the collection of interpretable diffraction data from microcrystals, there is a need for efficient methods of harvesting small volumes (<2 µl) of microcrystals grown under common laboratory formats and delivering them to an X-ray beam source under native growth conditions. One approach that shows promise in overcoming the challenges intrinsic to microcrystal analysis is to pair so-called `fixed-target' sample-delivery devices with microbeam-based X-ray diffraction methods. However, to record weak diffraction patterns it is necessarymore » to fabricate devices from X-ray-transparent materials that minimize background scattering. Presented here is the design of a new micro-diffraction device consisting of three layers fabricated from silicon nitride, photoresist and polyimide film. The chip features low X-ray scattering and X-ray absorption properties, and uses a customizable blend of hydrophobic and hydrophilic surface patterns to help localize microcrystals to defined regions. Microcrystals in their native growth conditions can be loaded into the chips with a standard pipette, allowing data collection at room temperature. Diffraction data collected from hen egg-white lysozyme microcrystals (10–15 µm) loaded into the chips yielded a complete, high-resolution (<1.6 Å) data set sufficient to determine a high-quality structure by molecular replacement. In addition, the features of the chip allow the rapid and user-friendly analysis of microcrystals grown under virtually any laboratory format at microfocus synchrotron beamlines and XFELs.« less

  8. X-ray scatter imaging of hepatocellular carcinoma in a mouse model using nanoparticle contrast agents

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

    Rand, Danielle; Derdak, Zoltan; Carlson, Rolf; Wands, Jack R.; Rose-Petruck, Christoph

    2015-10-29

    Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide and is almost uniformly fatal. Current methods of detection include ultrasound examination and imaging by CT scan or MRI; however, these techniques are problematic in terms of sensitivity and specificity, and the detection of early tumors (<1 cm diameter) has proven elusive. Better, more specific, and more sensitive detection methods are therefore urgently needed. Here we discuss the application of a newly developed x-ray imaging technique called Spatial Frequency Heterodyne Imaging (SFHI) for the early detection of HCC. SFHI uses x-rays scattered by an object to form anmore » image and is more sensitive than conventional absorption-based x-radiography. We show that tissues labeled in vivo with gold nanoparticle contrast agents can be detected using SFHI. We also demonstrate that directed targeting and SFHI of HCC tumors in a mouse model is possible through the use of HCC-specific antibodies. As a result, the enhanced sensitivity of SFHI relative to currently available techniques enables the x-ray imaging of tumors that are just a few millimeters in diameter and substantially reduces the amount of nanoparticle contrast agent required for intravenous injection relative to absorption-based x-ray imaging.« less

  9. X-ray scatter imaging of hepatocellular carcinoma in a mouse model using nanoparticle contrast agents

    SciTech Connect (OSTI)

    Rand, Danielle; Derdak, Zoltan; Carlson, Rolf; Wands, Jack R.; Rose-Petruck, Christoph

    2015-10-29

    Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide and is almost uniformly fatal. Current methods of detection include ultrasound examination and imaging by CT scan or MRI; however, these techniques are problematic in terms of sensitivity and specificity, and the detection of early tumors (<1 cm diameter) has proven elusive. Better, more specific, and more sensitive detection methods are therefore urgently needed. Here we discuss the application of a newly developed x-ray imaging technique called Spatial Frequency Heterodyne Imaging (SFHI) for the early detection of HCC. SFHI uses x-rays scattered by an object to form an image and is more sensitive than conventional absorption-based x-radiography. We show that tissues labeled in vivo with gold nanoparticle contrast agents can be detected using SFHI. We also demonstrate that directed targeting and SFHI of HCC tumors in a mouse model is possible through the use of HCC-specific antibodies. As a result, the enhanced sensitivity of SFHI relative to currently available techniques enables the x-ray imaging of tumors that are just a few millimeters in diameter and substantially reduces the amount of nanoparticle contrast agent required for intravenous injection relative to absorption-based x-ray imaging.

  10. X-ray transmissive debris shield

    DOE Patents [OSTI]

    Spielman, Rick B.

    1994-01-01

    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.

  11. High speed x-ray beam chopper

    DOE Patents [OSTI]

    McPherson, Armon; Mills, Dennis M.

    2002-01-01

    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.

  12. Gamma Radiation & X-Rays

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

    Gamma Radiation and X-Rays 1. Gamma radiation and X-rays are electromagnetic radiation like visible light, radio waves, and ultraviolet light. These electromagnetic radiations differ only in the amount of energy they have. Gamma rays and X-rays are the most energetic of these. 2. Gamma radiation is able to travel many meters in air and many centimeters in human tissue. It readily penetrates most materials and is sometimes called "penetrating radiation." 3. X-rays are like gamma rays.

  13. Lensless X-Ray Imaging in Reflection

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

    Lensless X-Ray Imaging in Reflection Lensless X-Ray 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 of lensless imaging. XFELs combine the advantages of sychrotron light sources (high brightness and x-ray wavelengths relevant to atomic and molecular phenomena) with the advantages of visible-light lasers (highly coherent beams). All of these characteristics are

  14. Lensless X-Ray Imaging in Reflection

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

    of sychrotron light sources (high brightness and x-ray wavelengths relevant to atomic and molecular phenomena) with the advantages of visible-light lasers (highly coherent beams). ...

  15. 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 combine the advantages of sychrotron light sources (high brightness and x-ray wavelengths relevant to atomic and molecular phenomena) with the advantages of visible-light lasers (highly coherent beams). All of these characteristics are important for coherent x-ray diffraction imaging-lensless imaging techniques that

  16. 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 combine the advantages of sychrotron light sources (high brightness and x-ray wavelengths relevant to atomic and molecular phenomena) with the advantages of visible-light lasers (highly coherent beams). All of these characteristics are important for coherent x-ray diffraction imaging-lensless imaging techniques that

  17. X-ray laser microscope apparatus

    DOE Patents [OSTI]

    Suckewer, Szymon; DiCicco, Darrell S.; Hirschberg, Joseph G.; Meixler, Lewis D.; Sathre, Robert; Skinner, Charles H.

    1990-01-01

    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.

  18. Lensless X-Ray Imaging in Reflection

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

    XFELs combine the advantages of sychrotron light sources (high brightness and x-ray wavelengths relevant to atomic and molecular phenomena) with the advantages of visible-light ...

  19. X-RAY EMISSION FROM MAGNETIC MASSIVE STARS

    SciTech Connect (OSTI)

    Naz, Yal; Petit, Vronique; Rinbrand, Melanie; Owocki, Stan; Cohen, David; Ud-Doula, Asif; Wade, Gregg A.

    2014-11-01

    Magnetically confined winds of early-type stars are expected to be sources of bright and hard X-rays. To clarify the systematics of the observed X-ray properties, we have analyzed a large series of Chandra and XMM-Newton observations, corresponding to all available exposures of known massive magnetic stars (over 100 exposures covering ?60% of stars compiled in the catalog of Petit et al.). We show that the X-ray luminosity is strongly correlated with the stellar wind mass-loss rate, with a power-law form that is slightly steeper than linear for the majority of the less luminous, lower- M-dot B stars and flattens for the more luminous, higher- M-dot O stars. As the winds are radiatively driven, these scalings can be equivalently written as relations with the bolometric luminosity. The observed X-ray luminosities, and their trend with mass-loss rates, are well reproduced by new MHD models, although a few overluminous stars (mostly rapidly rotating objects) exist. No relation is found between other X-ray properties (plasma temperature, absorption) and stellar or magnetic parameters, contrary to expectations (e.g., higher temperature for stronger mass-loss rate). This suggests that the main driver for the plasma properties is different from the main determinant of the X-ray luminosity. Finally, variations of the X-ray hardnesses and luminosities, in phase with the stellar rotation period, are detected for some objects and they suggest that some temperature stratification exists in massive stars' magnetospheres.

  20. X-ray Optics for BES Light Source Facilities

    SciTech Connect (OSTI)

    Mills, Dennis; Padmore, Howard; Lessner, Eliane

    2013-03-27

    nanolithographic techniques for improved spatial resolution and efficiency of zone plates. Development of large, perfect single crystals of materials other than silicon for use as beam splitters, seeding monochromators, and high-resolution analyzers. Development of improved thin-film deposition methods for fabrication of multilayer Laue lenses and high-spectral-resolution multilayer gratings. Development of supports, actuator technologies, algorithms, and controls to provide fully integrated and robust adaptive X-ray optic systems. Development of fabrication processes for refractive lenses in materials other than silicon. The workshop participants also addressed two important nontechnical areas: our relationship with industry and organization of optics within the light source facilities. Optimization of activities within these two areas could have an important effect on the effectiveness and efficiency of our overall endeavor. These are crosscutting managerial issues that we identified as areas that needed further in-depth study, but they need to be coordinated above the individual facilities. Finally, an issue that cuts across many of the optics improvements listed above is routine access to beamlines that ideally are fully dedicated to optics research and/or development. The success of the BES X-ray user facilities in serving a rapidly increasing user community has led to a squeezing of beam time for vital instrumentation activities. Dedicated development beamlines could be shared with other R&D activities, such as detector programs and novel instrument development. In summary, to meet the challenges of providing the highest-quality X-ray beams for users and to fully utilize the high-brightness sources of today and those that are on the horizon, it will be critical to make strategic investments in X-ray optics R&D. This report can provide guidance and direction for effective use of investments in the field of X-ray optics and potential approaches to develop a better

  1. Single-crystal X-ray diffraction at extreme conditions: a review...

    Office of Scientific and Technical Information (OSTI)

    Title: Single-crystal X-ray diffraction at extreme conditions: a review Authors: Ballaran, Tiziana Boffa ; Kurnosov, Alexander ; Trots, Dmytro 1 + Show Author Affiliations ...

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

    SciTech Connect (OSTI)

    Alvarez, Robert E.

    2013-11-15

    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. Biological imaging by soft x-ray diffraction microscopy

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

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

    2005-10-25

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

  4. X-ray Attenuation and Absorption Calculations.

    Energy Science and Technology Software Center (OSTI)

    1988-02-25

    This point-source, polychromatic, discrete energy X-ray transport and energy deposition code system calculates first-order spectral estimates of X-ray energy transmission through slab materials and the associated spectrum of energy absorbed by the material.

  5. Phased Contrast X-Ray Imaging

    ScienceCinema (OSTI)

    Erin Miller

    2012-12-31

    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.

  6. Accelerator-driven X-ray Sources

    SciTech Connect (OSTI)

    Nguyen, Dinh Cong

    2015-11-09

    After an introduction which mentions x-ray tubes and storage rings and gives a brief review of special relativity, the subject is treated under the following topics and subtopics: synchrotron radiation (bending magnet radiation, wiggler radiation, undulator radiation, brightness and brilliance definition, synchrotron radiation facilities), x-ray free-electron lasers (linac-driven X-ray FEL, FEL interactions, self-amplified spontaneous emission (SASE), SASE self-seeding, fourth-generation light source facilities), and other X-ray sources (energy recovery linacs, Inverse Compton scattering, laser wakefield accelerator driven X-ray sources. In summary, accelerator-based light sources cover the entire electromagnetic spectrum. Synchrotron radiation (bending magnet, wiggler and undulator radiation) has unique properties that can be tailored to the users’ needs: bending magnet and wiggler radiation is broadband, undulator radiation has narrow spectral lines. X-ray FELs are the brightest coherent X-ray sources with high photon flux, femtosecond pulses, full transverse coherence, partial temporal coherence (SASE), and narrow spectral lines with seeding techniques. New developments in electron accelerators and radiation production can potentially lead to more compact sources of coherent X-rays.

  7. Gray scale x-ray mask

    DOE Patents [OSTI]

    Morales, Alfredo M.; Gonzales, Marcela

    2006-03-07

    The present invention describes a method for fabricating an embossing tool or an x-ray mask tool, providing microstructures that smoothly vary in height from point-to-point in etched substrates, i.e., structure which can vary in all three dimensions. The process uses a lithographic technique to transfer an image pattern in the surface of a silicon wafer by exposing and developing the resist and then etching the silicon substrate. Importantly, the photoresist is variably exposed so that when developed some of the resist layer remains. The remaining undeveloped resist acts as an etchant barrier to the reactive plasma used to etch the silicon substrate and therefore provides the ability etch structures of variable depths.

  8. 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

    2013-06-01

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

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

    DOE Patents [OSTI]

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

    2014-06-10

    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.

  10. X-ray radiography with highly charged ions

    DOE Patents [OSTI]

    Marrs, Roscoe E. (Livermore, CA)

    2000-01-01

    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.

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

    SciTech Connect (OSTI)

    Schrapp, Michael J.; Goldammer, Matthias; Schulz, Michael; Issani, Siraj; Bhamidipati, Suryanarayana; Böni, Peter

    2014-10-28

    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.

  12. Measuring the X-ray Resolving Power of Bent Potassium Acid Phthalate

    Office of Scientific and Technical Information (OSTI)

    Diffraction Crystals (Conference) | SciTech Connect Conference: Measuring the X-ray Resolving Power of Bent Potassium Acid Phthalate Diffraction Crystals Citation Details In-Document Search Title: Measuring the X-ray Resolving Power of Bent Potassium Acid Phthalate Diffraction Crystals 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

  13. Cooling for a rotating anode X-ray tube

    DOE Patents [OSTI]

    Smither, Robert K. (Hinsdale, IL)

    1998-01-01

    A method and apparatus for cooling a rotating anode X-ray tube. An electromagnetic motor is provided to rotate an X-ray anode with cooling passages in the anode. These cooling passages are coupled to a cooling structure located adjacent the electromagnetic motor. A liquid metal fills the passages of the cooling structure and electrical power is provided to the motor to rotate the anode and generate a rotating magnetic field which moves the liquid metal through the cooling passages and cooling structure.

  14. Hyperspectral image reconstruction for x-ray fluorescence tomography

    SciTech Connect (OSTI)

    Grsoy, Do?a; Bier, Tekin; Lanzirotti, Antonio; Newville, Matthew G.; De Carlo, Francesco

    2015-01-01

    A penalized maximum-likelihood estimation is proposed to perform hyperspectral (spatio-spectral) image reconstruction for X-ray fluorescence tomography. The approach minimizes a Poisson-based negative log-likelihood of the observed photon counts, and uses a penalty term that has the effect of encouraging local continuity of model parameter estimates in both spatial and spectral dimensions simultaneously. The performance of the reconstruction method is demonstrated with experimental data acquired from a seed of arabidopsis thaliana collected at the 13-ID-E microprobe beamline at the Advanced Photon Source. The resulting element distribution estimates with the proposed approach show significantly better reconstruction quality than the conventional analytical inversion approaches, and allows for a high data compression factor which can reduce data acquisition times remarkably. In particular, this technique provides the capability to tomographically reconstruct full energy dispersive spectra without compromising reconstruction artifacts that impact the interpretation of results.

  15. Hyperspectral image reconstruction for x-ray fluorescence tomography

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

    Grsoy, Do?a; Bier, Tekin; Lanzirotti, Antonio; Newville, Matthew G.; De Carlo, Francesco

    2015-01-01

    A penalized maximum-likelihood estimation is proposed to perform hyperspectral (spatio-spectral) image reconstruction for X-ray fluorescence tomography. The approach minimizes a Poisson-based negative log-likelihood of the observed photon counts, and uses a penalty term that has the effect of encouraging local continuity of model parameter estimates in both spatial and spectral dimensions simultaneously. The performance of the reconstruction method is demonstrated with experimental data acquired from a seed of arabidopsis thaliana collected at the 13-ID-E microprobe beamline at the Advanced Photon Source. The resulting element distribution estimates with the proposed approach show significantly better reconstruction quality than the conventional analytical inversionmoreapproaches, and allows for a high data compression factor which can reduce data acquisition times remarkably. In particular, this technique provides the capability to tomographically reconstruct full energy dispersive spectra without compromising reconstruction artifacts that impact the interpretation of results.less

  16. Bragg x-ray survey spectrometer for ITER

    SciTech Connect (OSTI)

    Varshney, S. K.; Jakhar, S.; Barnsley, R.; O'Mullane, M. G.

    2012-10-15

    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.

  17. Soft X-ray techniques to study mesoscale magnetism

    SciTech Connect (OSTI)

    Kortright, Jeffrey B.

    2003-06-26

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

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

    SciTech Connect (OSTI)

    Kojima, Sadaoki Arikawa, Yasunobu; Zhang, Zhe; Ikenouchi, Takahito; Morace, Alessio; Nagai, Takahiro; Abe, Yuki; Sakata, Shouhei; Inoue, Hiroaki; Utsugi, Masaru; Nakai, Mitsuo; Nishimura, Hiroaki; Shiraga, Hiroyuki; Fujioka, Shinsuke; Azechi, Hiroshi; Nishimura, Yasuhiko; Togawa, Hiromi; Ozaki, Tetsuo; Kato, Ryukou

    2014-11-15

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

  19. K-alpha conversion efficiency measurments for x-ray scattering in inertial confinement fusion plasmas

    SciTech Connect (OSTI)

    Kritcher, A L; Neumayer, P; Urry, M K; Robey, H; Niemann, C; Landen, O L; Morse, E; Glenzer, S H

    2006-11-21

    The conversion efficiency of ultra short-pulse laser radiation to K-{alpha} x-rays has been measured for various chlorine-containing targets to be used as x-ray scattering probes of dense plasmas. The spectral and temporal properties of these sources will allow spectrally-resolved x-ray scattering probing with picosecond temporal resolution required for measuring the plasma conditions in inertial confinement fusion experiments. Simulations of x-ray scattering spectra from these plasmas show that fuel capsule density, capsule ablator density, and shock timing information may be inferred.

  20. Absolute timing measurements of the Ni-like Pd and Sn soft-x-ray lasers

    SciTech Connect (OSTI)

    Staub, F.; Braud, M.; Balmer, J.E.; Nilsen, J.

    2005-10-15

    The absolute time of emission of the x-ray laser output with respect to the arrival of a 100-ps pump pulse has been measured with the aid of a calibrated timing fiducial. The results show the x-ray laser to appear up to 60 ps (80 ps) before the peak of the pump pulse in the case of the Sn (Pd) x-ray laser, which is in good agreement with simulations obtained from the LASNEX and CRETIN codes. The pulse duration was found to be {approx}45 ps for both the Sn and the Pd x-ray lasers.

  1. Azimuthal anisotropy of the scattered radiation in grazing incidence X-ray fluorescence

    SciTech Connect (OSTI)

    Das, Gangadhar Tiwari, M. K.; Singh, A. K.; Ghosh, Haranath

    2015-06-24

    The Compton and elastic scattering radiations are the major contributor to the spectral background of an x-ray fluorescence spectrum, which eventually limits the element detection sensitivities of the technique to µg/g (ppm) range. In the present work, we provide a detail mathematical descriptions and show that how polarization properties of the synchrotron radiation influence the spectral background in the x-ray fluorescence technique. We demonstrate our theoretical understandings through experimental observations using total x-ray fluorescence measurements on standard reference materials. Interestingly, the azimuthal anisotropy of the scattered radiation is shown to have a vital role on the significance of the x-ray fluorescence detection sensitivities.

  2. The cool component and the dichotomy, lateral expansion, and axial rotation of solar X-ray jets

    SciTech Connect (OSTI)

    Moore, Ronald L.; Sterling, Alphonse C.; Falconer, David A.; Robe, Dominic

    2013-06-01

    We present results from a study of 54 polar X-ray jets that were observed in coronal X-ray movies from the X-ray Telescope on Hinode and had simultaneous coverage in movies of the cooler transition region (T ? 10{sup 5} K) taken in the He II 304 band of the Atmospheric Imaging Assembly (AIA) on Solar Dynamics Observatory. These dual observations verify the standard-jet/blowout-jet dichotomy of polar X-ray jets previously found primarily from XRT movies alone. In accord with models of blowout jets and standard jets, the AIA 304 movies show a cool (T ? 10{sup 5} K) component in nearly all blowout X-ray jets and in a small minority of standard X-ray jets, obvious lateral expansion in blowout X-ray jets but none in standard X-ray jets, and obvious axial rotation in both blowout X-ray jets and standard X-ray jets. In our sample, the number of turns of axial rotation in the cool-component standard X-ray jets is typical of that in the blowout X-ray jets, suggesting that the closed bipolar magnetic field in the jet base has substantial twist not only in all blowout X-ray jets but also in many standard X-ray jets. We point out that our results for the dichotomy, lateral expansion, and axial rotation of X-ray jets add credence to published speculation that type-II spicules are miniature analogs of X-ray jets, are generated by granule-size emerging bipoles, and thereby carry enough energy to power the corona and solar wind.

  3. X-rays Illuminate Ancient Archimedes Text

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

    ... DailyIndia.com: http:www.dailyindia.comshow48286.phpX-rays-illuminate-Archimedes-writings North Korea Times: http:story.northkoreatimes.comp.xct9ciddd8845aa60952db2id...

  4. Lensless X-Ray Imaging in Reflection

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

    Wednesday, 26 October 2011 00:00 The advent of x-ray free-electron laser (XFEL) light ... wavelengths relevant to atomic and molecular phenomena) with the advantages of ...

  5. X-ray grid-detector apparatus

    DOE Patents [OSTI]

    Boone, John M.; Lane, Stephen M.

    1998-01-27

    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.

  6. X-ray source for mammography

    DOE Patents [OSTI]

    Logan, C.M.

    1994-12-20

    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.

  7. Small Angle X-Ray Scattering Detector

    DOE Patents [OSTI]

    Hessler, Jan P.

    2004-06-15

    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.

  8. Femtosecond X-ray protein nanocrystallography

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

    pulses from a hard-X-ray free-electron laser, the Linac Coherent Light Source (4). ... We mitigate the problem of radiation damage in crystallography by using pulses briefer ...

  9. Lensless X-Ray Imaging in Reflection

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

    be reconstructed by a single Fourier transform; this is known as Fourier transform holography. The problem of getting sufficiently coherent x-rays onto and off of the sample in a...

  10. X-ray source for mammography

    DOE Patents [OSTI]

    Logan, Clinton M.

    1994-01-01

    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.

  11. X-ray image intensifier phosphor

    DOE Patents [OSTI]

    D'Silva, A.P.; Fassel, V.A.

    1975-12-01

    Y/sub 1-x/Gd/sub x/.PO$sub 4$:Tb$sup 3+$ is an effective phosphor for use in X-ray intensifier screens and in nuclear radiation detection systems.

  12. Biological Imaging by Soft X-Ray Diffraction Microscopy

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

    Biological Imaging by Soft X-Ray Diffraction Microscopy Biological Imaging by Soft X-Ray Diffraction Microscopy Print Wednesday, 30 November 2005 00:00 Electron and x-ray...

  13. Optimization efforts in gated x-ray intensifiers (Conference...

    Office of Scientific and Technical Information (OSTI)

    Optimization efforts in gated x-ray intensifiers Citation Details In-Document Search Title: Optimization efforts in gated x-ray intensifiers Gated x-ray intensifiers are often ...

  14. X-ray laser driven gold targets

    SciTech Connect (OSTI)

    Petrova, Tz. B. Whitney, K. G.; Davis, J.

    2014-03-15

    The femtosecond population dynamics of gold irradiated by a coherent high-intensity (>10{sup 17} W/cm{sup 2}) x-ray laser pulse is investigated theoretically. There are two aspects to the assembled model. One is the construction of a detailed model of platinum-like gold inclusive of all inner-shell states that are created by photoionization of atomic gold and decay either by radiative or Auger processes. Second is the computation of the population dynamics that ensues when an x-ray pulse is absorbed in gold. The hole state generation depends on the intensity and wavelength of the driving x-ray pulse. The excited state populations reached during a few femtosecond timescales are high enough to generate population inversions, whose gain coefficients are calculated. These amplified lines in the emitted x-ray spectrum provide important diagnostics of the radiation dynamics and also suggest a nonlinear way to increase the frequency of the coherent output x-ray pulses relative to the frequency of the driver input x-ray pulse.

  15. Compton backscattered collmated X-ray source

    DOE Patents [OSTI]

    Ruth, Ronald D.; Huang, Zhirong

    2000-01-01

    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.

  16. Compton backscattered collimated x-ray source

    DOE Patents [OSTI]

    Ruth, R.D.; Huang, Z.

    1998-10-20

    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.

  17. Compton backscattered collimated x-ray source

    DOE Patents [OSTI]

    Ruth, Ronald D.; Huang, Zhirong

    1998-01-01

    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.

  18. X-ray Imaging Shows Feather Patterns of First Birds

    Broader source: Energy.gov [DOE]

    One-hundred million years ago, what did birds look like? Scientists have taken a huge step towards finding the answer, leaving the creative imaginations behind such classics as Jurassic Park, The Land Before Time and Dinotopic to contend with science.

  19. Category:X-Ray Diffraction (XRD) | Open Energy Information

    Open Energy Info (EERE)

    X-Ray Diffraction (XRD) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermalpower.jpg Looking for the X-Ray Diffraction (XRD) page? For detailed information on...

  20. Direct synchrotron x-ray measurements of local strain fields...

    Office of Scientific and Technical Information (OSTI)

    Accepted Manuscript: Direct synchrotron x-ray measurements of local strain fields in ... September 3, 2016 Title: Direct synchrotron x-ray measurements of local strain fields in ...

  1. Generation of Coherent X-Ray Radiation through Modulation Compression...

    Office of Scientific and Technical Information (OSTI)

    Generation of Coherent X-Ray Radiation through Modulation Compression Citation Details In-Document Search Title: Generation of Coherent X-Ray Radiation through Modulation Compression ...

  2. Experimental X-ray characterization of Gekko XII laser propagation...

    Office of Scientific and Technical Information (OSTI)

    Experimental X-ray characterization of Gekko XII laser propagation through very low ... Citation Details In-Document Search Title: Experimental X-ray characterization of Gekko ...

  3. Integrated X-ray Reflectivity Measurements for Elliptically Curved...

    Office of Scientific and Technical Information (OSTI)

    Title: Integrated X-ray Reflectivity Measurements for Elliptically Curved PET Crystals The elliptically curved pentaerythritol (PET) crystals used in the Supersnout 2 X-ray ...

  4. Simultaneous cryo X-ray ptychographic and fluorescence microscopy...

    Office of Scientific and Technical Information (OSTI)

    Accepted Manuscript: Simultaneous cryo X-ray ptychographic and fluorescence microscopy of green algae Prev Next Title: Simultaneous cryo X-ray ptychographic and fluorescence ...

  5. A Spatially Resolving X-ray Crystal Spectrometer for Measurement...

    Office of Scientific and Technical Information (OSTI)

    394 PPPL- 4394 A Spatially Resolving X-ray Crystal Spectrometer for Measurement of ... Fusion Links A spatially resolving x-ray crystal spectrometer for measurement of ...

  6. Development of a Spatially Resolving X-Ray Crystal Spectrometer...

    Office of Scientific and Technical Information (OSTI)

    Development of a Spatially Resolving X-Ray Crystal Spectrometer For Measurement of ... Links Development of a spatially resolving x-ray crystal spectrometer for measurement of ...

  7. Development Of a Spatially Resolving X-ray Crystal Spectrometer...

    Office of Scientific and Technical Information (OSTI)

    Technical Report: Development Of a Spatially Resolving X-ray Crystal Spectrometer For ... Title: Development Of a Spatially Resolving X-ray Crystal Spectrometer For Measurement Of ...

  8. Integrated X-Ray Reflectivity Measurements for Elliptically Curved...

    Office of Scientific and Technical Information (OSTI)

    Integrated X-Ray Reflectivity Measurements for Elliptically Curved PET Crystals Citation Details In-Document Search Title: Integrated X-Ray Reflectivity Measurements for ...

  9. X-ray transient absorption and picosecond IR spectroscopy of...

    Office of Scientific and Technical Information (OSTI)

    X-ray transient absorption and picosecond IR spectroscopy of fulvalene(tetracarbonyl)diruthenium on photoexcitation Citation Details In-Document Search Title: X-ray transient ...

  10. Experimental X-ray characterization of Gekko XII laser propagation...

    Office of Scientific and Technical Information (OSTI)

    Experimental X-ray characterization of Gekko XII laser propagation through very low ... Title: Experimental X-ray characterization of Gekko XII laser propagation through very low ...

  11. X-Ray Microcomputed Tomography for the Durability Characterization...

    Office of Scientific and Technical Information (OSTI)

    Conference: X-Ray Microcomputed Tomography for the Durability Characterization of Limestone Aggregate Citation Details In-Document Search Title: X-Ray Microcomputed Tomography for...

  12. X-rays at Solid-Liquid Surfaces

    SciTech Connect (OSTI)

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

    2007-05-02

    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.

  13. Archimedes' Oldest Writings Under X-ray vision (BNL Women in Science Lecture Series)

    SciTech Connect (OSTI)

    Bergmann, Uwe

    2009-05-20

    Large parts of Archimedes’ writings were recently deciphered at the Stanford Synchrotron Radiation Lightsource at SLAC. A special x-ray technique showed maps of iron in faint traces of partially erased ink. The x-ray images revealed Archimedes’ writings from some of his most important works that were hidden by twelfth-century biblical texts, mold and forged gold paintings.

  14. X-ray imaging and controlled solidification of Al-Cu alloys toward microstructures by design

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

    Clarke, Amy J.; Tourret, Damien; Imhoff, Seth D.; Gibbs, Paul J.; Fezzaa, Kamel; Cooley, Jason C.; Lee, Wah -Keat; Deriy, Alex; Patterson, Brian M.; Papin, Pallas A.; et al

    2015-01-30

    X-ray imaging, which permits the microscopic visualization of metal alloy solidification dynamics, can be coupled with controlled solidification to create microstructures by design. This x-ray image shows a process-derived composite microstructure being made from a eutectic Al-17.1 at.%Cu alloy by successive solidification and remelting steps.

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

    DOE Patents [OSTI]

    Rosenberg, Richard A.; Goeppner, George A.; Noonan, John R.; Farrell, William J.; Ma, Qing

    1999-01-01

    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.

  16. Ultrafast X-Ray Coherent Control

    SciTech Connect (OSTI)

    Reis, David

    2009-05-01

    This main purpose of this grant was to develop the nascent #12;eld of ultrafast x-ray science using accelerator-based sources, and originally developed from an idea that a laser could modulate the di#11;racting properties of a x-ray di#11;racting crystal on a fast enough time scale to switch out in time a shorter slice from the already short x-ray pulses from a synchrotron. The research was carried out primarily at the Advanced Photon Source (APS) sector 7 at Argonne National Laboratory and the Sub-Picosecond Pulse Source (SPPS) at SLAC; in anticipation of the Linac Coherent Light Source (LCLS) x-ray free electron laser that became operational in 2009 at SLAC (all National User Facilities operated by BES). The research centered on the generation, control and measurement of atomic-scale dynamics in atomic, molecular optical and condensed matter systems with temporal and spatial resolution . It helped develop the ultrafast physics, techniques and scienti#12;c case for using the unprecedented characteristics of the LCLS. The project has been very successful with results have been disseminated widely and in top journals, have been well cited in the #12;eld, and have laid the foundation for many experiments being performed on the LCLS, the world's #12;rst hard x-ray free electron laser.

  17. A COMPARISON OF X-RAY AND MID-INFRARED SELECTION OF OBSCURED ACTIVE GALACTIC NUCLEI

    SciTech Connect (OSTI)

    Eckart, Megan E.; Harrison, Fiona A.; McGreer, Ian D.; Helfand, David J.; Stern, Daniel

    2010-01-01

    We compare the relative merits of active galactic nuclei (AGNs) selection at X-ray and mid-infrared wavelengths using data from moderately deep fields observed by both Chandra and Spitzer. The X-ray-selected AGN sample and associated photometric and spectroscopic optical follow-up are drawn from a subset of fields studied as part of the Serendipitous Extragalactic X-ray Source Identification (SEXSI) program. Mid-infrared data in these fields are derived from targeted and archival Spitzer imaging, and mid-infrared AGN selection is accomplished primarily through application of the Infrared Array Camera (IRAC) color-color AGN 'wedge' selection technique. Nearly all X-ray sources in these fields which exhibit clear spectroscopic signatures of AGN activity have mid-infrared colors consistent with IRAC AGN selection. These are predominantly the most luminous X-ray sources. X-ray sources that lack high-ionization and/or broad lines in their optical spectra are far less likely to be selected as AGNs by mid-infrared color selection techniques. The fraction of X-ray sources identified as AGNs in the mid-infrared increases monotonically as the X-ray luminosity increases. Conversely, only 22% of mid-infrared-selected AGNs are detected at X-ray energies in the moderately deep ((t{sub exp}) approx 100 ks) SEXSI Chandra data. We hypothesize that IRAC sources with AGN colors that lack X-ray detections are predominantly high-luminosity AGNs that are obscured and/or lie at high redshift. A stacking analysis of X-ray-undetected sources shows that objects in the mid-infrared AGN selection wedge have average X-ray fluxes in the 2-8 keV band 3 times higher than sources that fall outside the wedge. Their X-ray spectra are also harder. The hardness ratio of the wedge-selected stack is consistent with moderate intrinsic obscuration, but is not suggestive of a highly obscured, Compton-thick source population. It is evident from this comparative study that in order to create a complete

  18. 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.

  19. PROPX: An X-ray Manipulation Program

    SciTech Connect (OSTI)

    Kyrala, G.A.

    1992-05-01

    An interactive micro-computer program that performs some manipulations on an input x-ray spectrum is introduced and described. The program is used to calculate the effect of absorption of filters, transmission through fibers, responsivity of photocathodes, responsivity of absorptive detectors, folding of responses, plotting of cross sections, and calculation, as a function of electron temperature, of the response due to a bremsstrahlung spectrum. Fluorescence from the targets is not included. Two different x-ray libraries are offered, one covers the x-ray range 30--10,000 eV with 288 energy points, and the other covers the energy range 10 eV to 1 MeV with 250 energy points per decade. 7 refs.

  20. Differential phase contrast X-ray imaging system and components

    DOE Patents [OSTI]

    Stutman, Daniel; Finkenthal, Michael

    2014-07-01

    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.

  1. Some new schemes for producing high-accuracy elliptical X-ray mirrors by elastic bending

    SciTech Connect (OSTI)

    Padmore, H.A.; Howells, M.R.; Irick, S.; Renner, T.; Sandler, R.; Koo, Y.-M.

    1996-08-01

    Although x-ray micro-foci can be produced by a variety of diffractive methods, grazing incidence mirrors are the only route to an achromatic focus. In this paper we describe our efforts to produce elliptically shaped mirrors with the very high figure accuracy necessary for producing a micro-focus. The motivation for this work is provided by the need to produce achromatic foci for a range of applications ranging from tunable micro-focus x-ray photoelectron spectroscopy ({mu}-XPS) at soft x-ray energies to micro-focus white beam x-ray diffraction ({mu}-XRD) at hard x-ray energies. We describe the methodology of beam bending, a practical example of a system we have produced for {mu}-XRD, and results demonstrating the production of a surface with micro-radian figure accuracy.

  2. Compound refractive lenses as prefocusing optics for X-ray FEL radiation

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

    Heimann, Philip; MacDonald, Michael; Nagler, Bob; Lee, Hae Ja; Galtier, Eric; Arnold, Brice; Xing, Zhou

    2016-01-27

    The performance of X-ray free-electron laser beamlines may be limited by the angular aperture. Compound refractive lenses (CRLs) can be employed to prefocus the X-ray beam, thereby increasing the beamline transmission. A prefocusing CRL was implemented in the X-ray transport of the Matter under Extreme Conditions Instrument at the Linac Coherent Light Source. A significant improvement in the beamline transmission was calculated over the 3–10 keV photon energy range. At 5 keV, the relative X-ray intensity was measured and a factor of four increase was seen in the beamline transmission. As a result, the X-ray focus was also determined bymore » the ablation imprint method.« less

  3. 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

    2013-02-01

    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.

  4. Energy resolved X-ray grating interferometry

    SciTech Connect (OSTI)

    Thuering, T.; Stampanoni, M.; Institute for Biomedical Engineering, Swiss Federal Institute of Technology, Zurich ; Barber, W. C.; Iwanczyk, J. S.; Seo, Y.; Alhassen, F.

    2013-05-13

    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.

  5. Optimal focusing for a linac-based hard x-ray source

    SciTech Connect (OSTI)

    Liu, C.; Krafft, G.; Talman, R.

    2011-03-28

    In spite of having a small average beam current limit, a linac can have features that make it attractive as an x-ray source: high energy, ultralow emittance and energy spread, and flexible beamline optics. Unlike a storage ring, in which an (undulator) radiation source is necessarily short and positioned at an electron beam waist, in a linac the undulator can be long and the electron beam can be adjusted to have a (virtual) waist far downstream toward the x-ray target. Using a planned CEBAF beamline as an example, this paper shows that a factor of 2000 in beam current can be overcome to produce a monochromatic hard x-ray source comparable with, or even exceeding, the performance of an x-ray line at a third generation storage ring. Optimal electron beam focusing conditions for x-ray flux density and brilliance are derived, and are verified by simulations using the SRW code.

  6. Optimization and evaluation of metal injection molding by using X-ray tomography

    SciTech Connect (OSTI)

    Yang, Shidi; Zhang, Ruijie; Qu, Xuanhui

    2015-06-15

    6061 aluminum alloy and 316L stainless steel green bodies were obtained by using different injection parameters (injection pressure, speed and temperature). After injection process, the green bodies were scanned by X-ray tomography. The projection and reconstruction images show the different kinds of defects obtained by the improper injection parameters. Then, 3D rendering of the Al alloy green bodies was used to demonstrate the spatial morphology characteristics of the serious defects. Based on the scanned and calculated results, it is convenient to obtain the proper injection parameters for the Al alloy. Then, reasons of the defect formation were discussed. During mold filling, the serious defects mainly formed in the case of low injection temperature and high injection speed. According to the gray value distribution of projection image, a threshold gray value was obtained to evaluate whether the quality of green body can meet the desired standard. The proper injection parameters of 316L stainless steel can be obtained efficiently by using the method of analyzing the Al alloy injection. - Highlights: • Different types of defects in green bodies were scanned by using X-ray tomography. • Reasons of the defect formation were discussed. • Optimization of the injection parameters can be simplified greatly by the way of X-ray tomography. • Evaluation standard of the injection process can be obtained by using the gray value distribution of projection image.

  7. Observing the setting and hardening of cementitious materials by X-ray dark-field radiography

    SciTech Connect (OSTI)

    Prade, F.; Chabior, M.; Malm, F.; Grosse, C.U.; Pfeiffer, F.

    2015-08-15

    Novel X-ray imaging methods expand conventional attenuation-based X-ray radiography by the phase- and the dark-field contrasts. While weakly absorbing structures in the specimen can be better visualized in phase contrast, the dark-field contrast provides information about morphological sub-pixel microstructures. Here we report an application of dark-field X-ray radiography for imaging the time-resolved setting process in fresh cement. Our results demonstrate that the microstructural changes within the cement result in a decreasing dark-field signal. We quantify this imaging signal with a time-dependent dark-field scatter coefficient and show its good correlation with the compressional wave velocity. We further present images based on a pixel-wise analysis of the scattering signal and a corresponding logistic fit. These images emphasize the benefit of dark-field imaging of cementitious materials as it provides two dimensional spatial information on the processes within the sample while other established testing techniques only provide information on the bulk average.

  8. 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

    2004-09-24

    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.

  9. SWIFT X-RAY OBSERVATIONS OF CLASSICAL NOVAE. II. THE SUPER SOFT SOURCE SAMPLE

    SciTech Connect (OSTI)

    Schwarz, Greg J.; Ness, Jan-Uwe; Osborne, J. P.; Page, K. L.; Evans, P. A.; Beardmore, A. P.; Walter, Frederick M.; Andrew Helton, L.; Woodward, Charles E.; Bode, Mike; Starrfield, Sumner; Drake, Jeremy J.

    2011-12-01

    The Swift gamma-ray burst satellite is an excellent facility for studying novae. Its rapid response time and sensitive X-ray detector provides an unparalleled opportunity to investigate the previously poorly sampled evolution of novae in the X-ray regime. This paper presents Swift observations of 52 Galactic/Magellanic Cloud novae. We included the X-Ray Telescope (0.3-10 keV) instrument count rates and the UltraViolet and Optical Telescope (1700-8000 A) filter photometry. Also included in the analysis are the publicly available pointed observations of 10 additional novae the X-ray archives. This is the largest X-ray sample of Galactic/Magellanic Cloud novae yet assembled and consists of 26 novae with Super Soft X-ray emission, 19 from Swift observations. The data set shows that the faster novae have an early hard X-ray phase that is usually missing in slower novae. The Super Soft X-ray phase occurs earlier and does not last as long in fast novae compared to slower novae. All the Swift novae with sufficient observations show that novae are highly variable with rapid variability and different periodicities. In the majority of cases, nuclear burning ceases less than three years after the outburst begins. Previous relationships, such as the nuclear burning duration versus t{sub 2} or the expansion velocity of the eject and nuclear burning duration versus the orbital period, are shown to be poorly correlated with the full sample indicating that additional factors beyond the white dwarf mass and binary separation play important roles in the evolution of a nova outburst. Finally, we confirm two optical phenomena that are correlated with strong, soft X-ray emission which can be used to further increase the efficiency of X-ray campaigns.

  10. Research Opportunities in Photochemistry, Solar Energy & Advanced X-ray

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

    Methods (Stanford, CA) - JCAP Research Opportunities in Photochemistry, Solar Energy & Advanced X-ray Methods (Stanford, CA) Research Opportunities in Photochemistry, Solar Energy & Advanced X-ray Methods (Stanford, CA) Thu, Jun 16, 2016 12:00pm 12:00 Fri, Jun 17, 2016 1:00pm 13:00 "The workshop is aimed at strengthening the connection between mission needs in Basic Energy Sciences and the X-ray facilities and in particular identifying key questions in solar energy conversion

  11. First Principles Calculations for X-ray Resonant Spectra and Elastic Properties

    SciTech Connect (OSTI)

    Yongbin Lee

    2006-05-01

    In this thesis, we discuss applications of first principles methods to x-ray resonant spectra and elastic properties calculation. We start with brief reviews about theoretical background of first principles methods, such as density functional theory, local density approximation (LDA), LDA+U, and the linear augmented plane wave (LAPW) method to solve Kohn-Sham equations. After that we discuss x-ray resonant scattering (XRMS), x-ray magnetic circular dichroism (XMCD) and the branching problem in the heavy rare earths Ledges. In the last chapter we discuss the elastic properties of the second hardest material AlMgB{sub 14}.

  12. Small Angle X-Ray Scattering Detector

    DOE Patents [OSTI]

    Hessler, Jan P.

    2004-06-15

    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., q.sub.max /q.sub.min.congruent.100.

  13. SLAC All Access: X-ray Microscope

    ScienceCinema (OSTI)

    Nelson, Johanna; Liu, Yijin

    2014-06-13

    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.

  14. X-ray spectroscopy of manganese clusters

    SciTech Connect (OSTI)

    Grush, M.M.

    1996-06-01

    Much of this thesis represents the groundwork necessary in order to probe Mn clusters more productively than with conventional Mn K-edge XAS and is presented in Part 1. Part 2 contains the application of x-ray techniques to Mn metalloproteins and includes a prognosis at the end of each chapter. Individual Mn oxidation states are more readily distinguishable in Mn L-edge spectra. An empirical mixed valence simulation routine for determining the average Mn oxidation state has been developed. The first Mn L-edge spectra of a metalloprotein were measured and interpreted. The energy of Mn K{beta} emission is strongly correlated with average Mn oxidation state. K{beta} results support oxidation states of Mn(III){sub 2}(IV){sub 2} for the S{sub 1} state of Photosystem II chemical chemically reduced preparations contain predominantly Mn(II). A strength and limitation of XAS is that it probes all of the species of a particular element in a sample. It would often be advantageous to selectively probe different forms of the same element. The first demonstration that chemical shifts in x-ray fluorescence energies can be used to obtain oxidation state-selective x-ray absorption spectra is presented. Spin-dependent spectra can also be used to obtain a more simplified picture of local structure. The first spin-polarized extended x-ray absorption fine structure using Mn K{beta} fluorescence detection is shown.

  15. Development of an X-ray pixel detector with multi-port charge-coupled device for X-ray free-electron laser experiments

    SciTech Connect (OSTI)

    Kameshima, Takashi; Ono, Shun; Kudo, Togo; Ozaki, Kyosuke; Kirihara, Yoichi; Kobayashi, Kazuo; Inubushi, Yuichi; Yabashi, Makina; Hatsui, Takaki; Horigome, Toshio; Holland, Andrew; Holland, Karen; Burt, David; Murao, Hajime

    2014-03-15

    This paper presents development of an X-ray pixel detector with a multi-port charge-coupled device (MPCCD) for X-ray Free-Electron laser experiments. The fabrication process of the CCD was selected based on the X-ray radiation hardness against the estimated annual dose of 1.6 × 10{sup 14} photon/mm{sup 2}. The sensor device was optimized by maximizing the full well capacity as high as 5 Me- within 50 μm square pixels while keeping the single photon detection capability for X-ray photons higher than 6 keV and a readout speed of 60 frames/s. The system development also included a detector system for the MPCCD sensor. This paper summarizes the performance, calibration methods, and operation status.

  16. Project Title: Radiochemical Analysis by High Sensitivity Dual-Optic Micro X-ray Fluorescence

    SciTech Connect (OSTI)

    Havrilla, George J.; Gao, Ning

    2002-06-01

    A novel dual-optic micro X-ray fluorescence instrument will be developed to do radiochemical analysis of high-level radioactive wastes at DOE sites such as Savannah River Site and Hanford. This concept incorporates new X-ray optical elements such as monolithic polycapillaries and double bent crystals, which focus X-rays. The polycapillary optic can be used to focus X-rays emitted by the X-ray tube thereby increasing the X-ray flux on the sample over 1000 times. Polycapillaries will also be used to collect the X-rays from the excitation site and screen the radiation background from the radioactive species in the specimen. This dual-optic approach significantly reduces the background and increases the analyte signal thereby increasing the sensitivity of the analysis. A doubly bent crystal used as the focusing optic produces focused monochromatic X-ray excitation, which eliminates the bremsstrahlung background from the X-ray source. The coupling of the doubly bent crystal for monochromatic excitation with a polycapillary for signal collection can effectively eliminate the noise background and radiation background from the specimen. The integration of these X-ray optics increases the signal-to-noise and thereby increases the sensitivity of the analysis for low-level analytes. This work will address a key need for radiochemical analysis of high-level waste using a non-destructive, multi-element, and rapid method in a radiation environment. There is significant potential that this instrumentation could be capable of on-line analysis for process waste stream characterization at DOE sites.

  17. X-Ray Measurements Of A Thermo Scientific P385 DD Neutron Generator

    SciTech Connect (OSTI)

    Wharton, C. J.; Seabury, E. H.; Chichester, D. L.; Caffrey, A. J.; Simpson, J.; Lemchak, M.

    2011-06-01

    Idaho National Laboratory is experimenting with electrical neutron generators, as potential replacements for californium-252 radioisotopic neutron sources in its PINS prompt gamma-ray neutron activation analysis (PGNAA) system for the identification of military chemical warfare agents and explosives. In addition to neutron output, we have recently measured the x-ray output of the Thermo Scientific P385 deuterium-deuterium neutron generator. X rays are a normal byproduct from neutron generators, but depending on their intensity and energy, x rays can interfere with gamma rays from the object under test, increase gamma-spectrometer dead time, and reduce PGNAA system throughput. The P385 x-ray energy spectrum was measured with a high-purity germanium (HPGe) detector, and a broad peak is evident at about 70 keV. To identify the source of the x rays within the neutron generator assembly, it was scanned by collimated scintillation detectors along its long axis. At the strongest x-ray emission points, the generator also was rotated 60 deg. between measurements. The scans show the primary source of x-ray emission from the P385 neutron generator is an area 60 mm from the neutron production target, in the vicinity of the ion source. Rotation of the neutron generator did not significantly alter the x-ray count rate, and its x-ray emission appears to be axially symmetric. A thin lead shield, 3.2 mm (1/8 inch) thick, reduced the 70-keV generator x rays to negligible levels.

  18. 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.

    2012-03-13

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

  19. Kinematics of Compton backscattering x-ray source for angiography

    SciTech Connect (OSTI)

    Blumberg, L.N.

    1992-05-01

    Calculations of X-Ray production rates, energy spread, and spectrum of Compton-backscattered photons from a Free Electron Laser on an electron beam in a low energy (136-MeV) compact (8.5-m circumference) storage ring indicate that an X-Ray intensity of 34.6 10{sup 7} X-Ray photons per 0.5-mm {times} 0.5-mm pixel for Coronary Angiography near the 33.169-keV iodine K-absorption edge can be achieved in a 4-msec pulse within a scattering cone of 1-mrad half angle. This intensity, at 10-m from the photon-electron interaction point to the patient is about a factor of 10 larger than presently achieved from a 4.5-T superconducting wiggler source in the NSLS 2.5-GeV storage ring and over an area about 5 times larger. The 2.2-keV energy spread of the Compton-backscattered beam is, however, much larger than the 70-eV spread presently attained form the wiggler source and use of a monochromator. The beam spot at the 10-m interaction point-to-patient distance is 20-mm diameter; larger spots are attainable at larger distances but with a corresponding reduction in X-Ray flux. Such a facility could be an inexpensive clinical alternative to present methods of non-invasive Digital Subtraction Angiography (DSA), small enough to be deployed in an urban medical center, and could have other medical, industrial and aerospace applications. Problems with the Compton backscattering source include laser beam heating of the mirror in the FEL oscillator optical cavity, achieving a large enough X-Ray beam spot at the patient, and obtaining radiation damping of the transverse oscillations and longitudinal emittance dilution of the storage ring electron beam resulting from photon-electron collisions without going to higher electron energy where the X-Ray energy spread becomes excessive for DSA. 38 refs.

  20. Proton-induced x-ray fluorescence CT imaging

    SciTech Connect (OSTI)

    Bazalova-Carter, Magdalena Xing, Lei; Ahmad, Moiz; Matsuura, Taeko; Takao, Seishin; Shirato, Hiroki; Umegaki, Kikuo; Matsuo, Yuto; Fahrig, Rebecca

    2015-02-15

    Purpose: To demonstrate the feasibility of proton-induced x-ray fluorescence CT (pXFCT) imaging of gold in a small animal sized object by means of experiments and Monte Carlo (MC) simulations. Methods: First, proton-induced gold x-ray fluorescence (pXRF) was measured as a function of gold concentration. Vials of 2.2 cm in diameter filled with 0%–5% Au solutions were irradiated with a 220 MeV proton beam and x-ray fluorescence induced by the interaction of protons, and Au was detected with a 3 × 3 mm{sup 2} CdTe detector placed at 90° with respect to the incident proton beam at a distance of 45 cm from the vials. Second, a 7-cm diameter water phantom containing three 2.2-diameter vials with 3%–5% Au solutions was imaged with a 7-mm FWHM 220 MeV proton beam in a first generation CT scanning geometry. X-rays scattered perpendicular to the incident proton beam were acquired with the CdTe detector placed at 45 cm from the phantom positioned on a translation/rotation stage. Twenty one translational steps spaced by 3 mm at each of 36 projection angles spaced by 10° were acquired, and pXFCT images of the phantom were reconstructed with filtered back projection. A simplified geometry of the experimental data acquisition setup was modeled with the MC TOPAS code, and simulation results were compared to the experimental data. Results: A linear relationship between gold pXRF and gold concentration was observed in both experimental and MC simulation data (R{sup 2} > 0.99). All Au vials were apparent in the experimental and simulated pXFCT images. Specifically, the 3% Au vial was detectable in the experimental [contrast-to-noise ratio (CNR) = 5.8] and simulated (CNR = 11.5) pXFCT image. Due to fluorescence x-ray attenuation in the higher concentration vials, the 4% and 5% Au contrast were underestimated by 10% and 15%, respectively, in both the experimental and simulated pXFCT images. Conclusions: Proton-induced x-ray fluorescence CT imaging of 3%–5% gold solutions in a

  1. Bandpass x-ray diode and x-ray multiplier detector

    DOE Patents [OSTI]

    Wang, C.L.

    1982-09-27

    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.

  2. Principles of femtosecond X-ray/optical cross-correlation with X-ray induced transient optical reflectivity in solids

    SciTech Connect (OSTI)

    Eckert, S. E-mail: martin.beye@helmholtz-berlin.de; Beye, M. E-mail: martin.beye@helmholtz-berlin.de; Pietzsch, A.; Quevedo, W.; Hantschmann, M.; Ochmann, M.; Huse, N.; Ross, M.; Khalil, M.; Minitti, M. P.; Turner, J. J.; Moeller, S. P.; Schlotter, W. F.; Dakovski, G. L.; Föhlisch, A.

    2015-02-09

    The discovery of ultrafast X-ray induced optical reflectivity changes enabled the development of X-ray/optical cross correlation techniques at X-ray free electron lasers worldwide. We have now linked through experiment and theory the fundamental excitation and relaxation steps with the transient optical properties in finite solid samples. Therefore, we gain a thorough interpretation and an optimized detection scheme of X-ray induced changes to the refractive index and the X-ray/optical cross correlation response.

  3. Inelastic X-ray Scattering from Shocked Liquid Deuterium

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

    Regan, S. P.; Falk, K.; Gregori, G.; Radha, P. B.; Hu, S. X.; Boehly, T. R.; Crowley, B.; Glenzer, S. H.; Landen, O.; Gericke, D. O.; et al

    2012-12-28

    The Fermi-degenerate plasma conditions created in liquid deuterium by a laser-ablation—driven shock wave were probed with noncollective, spectrally resolved, inelastic x-ray Thomson scattering employing Cl Lyα line emission at 2.96 keV. Thus, these first x-ray Thomson scattering measurements of the microscopic properties of shocked deuterium show an inferred spatially averaged electron temperature of 8±5 eV, an electron density of 2.2(±0.5)×1023 cm-3, and an ionization of 0.8 (-0.25, +0.15). Our two-dimensional hydrodynamic simulations using equation-of-state models suited for the extreme parameters occurring in inertial confinement fusion research and planetary interiors are consistent with the experimental results.

  4. Inelastic X-ray Scattering from Shocked Liquid Deuterium

    SciTech Connect (OSTI)

    Regan, S. P.; Falk, K.; Gregori, G.; Radha, P. B.; Hu, S. X.; Boehly, T. R.; Crowley, B.; Glenzer, S. H.; Landen, O.; Gericke, D. O.; Doeppner, T.; Meyerhofer, D. D.; Murphy, C. D.; Sangster, T. C.; Vorberger, J.

    2012-12-28

    The Fermi-degenerate plasma conditions created in liquid deuterium by a laser-ablation—driven shock wave were probed with noncollective, spectrally resolved, inelastic x-ray Thomson scattering employing Cl Lyα line emission at 2.96 keV. Thus, these first x-ray Thomson scattering measurements of the microscopic properties of shocked deuterium show an inferred spatially averaged electron temperature of 8±5 eV, an electron density of 2.2(±0.5)×1023 cm-3, and an ionization of 0.8 (-0.25, +0.15). Our two-dimensional hydrodynamic simulations using equation-of-state models suited for the extreme parameters occurring in inertial confinement fusion research and planetary interiors are consistent with the experimental results.

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

    SciTech Connect (OSTI)

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

    2015-01-30

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

  6. Neutron and X-ray Detectors

    SciTech Connect (OSTI)

    Carini, Gabriella; Denes, Peter; Gruener, Sol; Lessner, Elianne

    2012-08-01

    The Basic Energy Sciences (BES) X-ray and neutron user facilities attract more than 12,000 researchers each year to perform cutting-edge science at these state-of-the-art sources. While impressive breakthroughs in X-ray and neutron sources give us the powerful illumination needed to peer into the nano- to mesoscale world, a stumbling block continues to be the distinct lag in detector development, which is slowing progress toward data collection and analysis. Urgently needed detector improvements would reveal chemical composition and bonding in 3-D and in real time, allow researchers to watch “movies” of essential life processes as they happen, and make much more efficient use of every X-ray and neutron produced by the source The immense scientific potential that will come from better detectors has triggered worldwide activity in this area. Europe in particular has made impressive strides, outpacing the United States on several fronts. Maintaining a vital U.S. leadership in this key research endeavor will require targeted investments in detector R&D and infrastructure. To clarify the gap between detector development and source advances, and to identify opportunities to maximize the scientific impact of BES user facilities, a workshop on Neutron and X-ray Detectors was held August 1-3, 2012, in Gaithersburg, Maryland. Participants from universities, national laboratories, and commercial organizations from the United States and around the globe participated in plenary sessions, breakout groups, and joint open-discussion summary sessions. Sources have become immensely more powerful and are now brighter (more particles focused onto the sample per second) and more precise (higher spatial, spectral, and temporal resolution). To fully utilize these source advances, detectors must become faster, more efficient, and more discriminating. In supporting the mission of today’s cutting-edge neutron and X-ray sources, the workshop identified six detector research challenges

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

    DOE Patents [OSTI]

    Bitter, Manfred L.; Fraenkel, Ben; Gorman, James L.; Hill, Kenneth W.; Roquemore, A. Lane; Stodiek, Wolfgang; von Goeler, Schweickhard E.

    2001-01-01

    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.

  8. EVIDENCE OF NON-THERMAL X-RAY EMISSION FROM HH 80

    SciTech Connect (OSTI)

    Lpez-Santiago, J.; Peri, C. S.; Benaglia, P.; Bonito, R.; Miceli, M.; Albacete-Colombo, J. F.; De Castro, E.

    2013-10-20

    Protostellar jets appear at all stages of star formation when the accretion process is still at work. Jets travel at velocities of hundreds of km s{sup 1}, creating strong shocks when interacting with the interstellar medium. Several cases of jets have been detected in X-rays, typically showing soft emission. For the first time, we report evidence of hard X-ray emission possibly related to non-thermal processes not explained by previous models of the post-shock emission predicted in the jet/ambient interaction scenario. HH 80 is located at the south head of the jet associated with the massive protostar IRAS 18162-2048. It shows soft and hard X-ray emission in regions that are spatially separated, with the soft X-ray emission region situated behind the region of hard X-ray emission. We propose a scenario for HH 80 where soft X-ray emission is associated with thermal processes from the interaction of the jet with denser ambient matter and hard X-ray emission is produced by synchrotron radiation at the front shock.

  9. Note: Electrochemical cell for in operando X-ray diffraction measurements on a conventional X-ray diffractometer

    SciTech Connect (OSTI)

    Hartung, Steffen; Bucher, Nicolas; Bucher, Ramona; Srinivasan, Madhavi

    2015-08-15

    Electrochemical in operando X-ray diffraction (XRD) is a powerful method to analyze structural changes of energy storage materials while inserting/de-inserting charge carriers, such as Li- or Na-ions, into/from a host structure. The design of an XRD in operando cell is presented, which enables the use of thin (6 μm) aluminum foil as X-ray window as a non-toxic alternative to conventional beryllium windows. Owing to the reduced thickness, diffraction patterns and their changes during cycling can be observed with excellent quality, which was demonstrated for two cathode materials for sodium-ion batteries in a half-cell set-up, P2-Na{sub 0.7}MnO{sub 2} and Na{sub 2.55}V{sub 6}O{sub 16} ⋅ 0.6H{sub 2}O.

  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)

    2013-03-20

    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. Application of x-ray imaging to oil refinery processes

    SciTech Connect (OSTI)

    Gamblin, B.R.; Newton, D.; Smith, G.B.

    1996-12-31

    X-ray imaging is a non-intrusive method of visualizing the flow patterns of rapidly changing multiphase systems and is based on the variation in the absorbance of X-rays by the different phases. BP has applied the X-ray technique to a variety of problems encountered within the oil and petrochemical industries in which two or three phases are present e.g. Fluid Catalytic Cracking (riser, stripper, regenerator) and three phase systems such as slurry bubble column reactors. In general, to obtain the maximum productivity from these units it is essential to optimize the contacting between a catalyst and a process fluid or fluids. This work reports on laboratory experimental work in which full scale refinery components were visualized in order to characterize the existing designs. Modified designs were then tested and evaluated before implementation on the refinery unit. Economic assessments of some of the benefits which can be realized in an oil refinery as a result of such design improvements are also presented. 3 refs., 1 fig.

  12. Automatic classification of time-variable X-ray sources

    SciTech Connect (OSTI)

    Lo, Kitty K.; Farrell, Sean; Murphy, Tara; Gaensler, B. M.

    2014-05-01

    To maximize the discovery potential of future synoptic surveys, especially in the field of transient science, it will be necessary to use automatic classification to identify some of the astronomical sources. The data mining technique of supervised classification is suitable for this problem. Here, we present a supervised learning method to automatically classify variable X-ray sources in the Second XMM-Newton Serendipitous Source Catalog (2XMMi-DR2). Random Forest is our classifier of choice since it is one of the most accurate learning algorithms available. Our training set consists of 873 variable sources and their features are derived from time series, spectra, and other multi-wavelength contextual information. The 10 fold cross validation accuracy of the training data is ∼97% on a 7 class data set. We applied the trained classification model to 411 unknown variable 2XMM sources to produce a probabilistically classified catalog. Using the classification margin and the Random Forest derived outlier measure, we identified 12 anomalous sources, of which 2XMM J180658.7–500250 appears to be the most unusual source in the sample. Its X-ray spectra is suggestive of a ultraluminous X-ray source but its variability makes it highly unusual. Machine-learned classification and anomaly detection will facilitate scientific discoveries in the era of all-sky surveys.

  13. The hidden X-ray breaks in afterglow light curves

    SciTech Connect (OSTI)

    Curran, P. A.; Wijers, R. A. M. J.; Horst, A. J. van der; Starling, R. L. C.

    2008-05-22

    Gamma-Ray Burst (GRB) afterglow observations in the Swift era have a perceived lack of achromatic jet breaks compared to the BeppoSAX, or pre-Swift era. Specifically, relatively few breaks, consistent with jet breaks, are observed in the X-ray light curves of these bursts. If these breaks are truly missing, it has serious consequences for the interpretation of GRB jet collimation and energy requirements, and the use of GRBs as standard candles.Here we address the issue of X-ray breaks which are possibly 'hidden' and hence the light curves are misinterpreted as being single power-laws. We show how a number of precedents, including GRB 990510 and GRB 060206, exist for such hidden breaks and how, even with the well sampled light curves of the Swift era, these breaks may be left misidentified. We do so by synthesising X-ray light curves and finding general trends via Monte Carlo analysis. Furthermore, in light of these simulations, we discuss how to best identify achromatic breaks in afterglow light curves via multi-wavelength analysis.

  14. Rise time measurement for ultrafast X-ray pulses

    DOE Patents [OSTI]

    Celliers, Peter M.; Weber, Franz A.; Moon, Stephen J.

    2005-04-05

    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.

  15. Rise Time Measurement for Ultrafast X-Ray Pulses

    DOE Patents [OSTI]

    Celliers, Peter M.; Weber, Franz A.; Moon, Stephen J.

    2005-04-05

    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.

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

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

    Lensless Imaging of Whole Biological Cells with Soft X-Rays Print A team of scientists has used x-ray diffraction microscopy at ALS Beamline 9.0.1 to make images of whole yeast cells, achieving the highest resolution-11 to 13 nanometers (billionths of a meter)-ever obtained with this method for biological specimens. Their success indicates that full 3-D tomography of whole cells at equivalent resolution should soon be possible. The National Center for X-Ray Tomography at ALS Beamline 2.1 images

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

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

    Lensless Imaging of Whole Biological Cells with Soft X-Rays Print A team of scientists has used x-ray diffraction microscopy at ALS Beamline 9.0.1 to make images of whole yeast cells, achieving the highest resolution-11 to 13 nanometers (billionths of a meter)-ever obtained with this method for biological specimens. Their success indicates that full 3-D tomography of whole cells at equivalent resolution should soon be possible. The National Center for X-Ray Tomography at ALS Beamline 2.1 images

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

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

    Lensless Imaging of Whole Biological Cells with Soft X-Rays Print A team of scientists has used x-ray diffraction microscopy at ALS Beamline 9.0.1 to make images of whole yeast cells, achieving the highest resolution-11 to 13 nanometers (billionths of a meter)-ever obtained with this method for biological specimens. Their success indicates that full 3-D tomography of whole cells at equivalent resolution should soon be possible. The National Center for X-Ray Tomography at ALS Beamline 2.1 images

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

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

    Lensless Imaging of Whole Biological Cells with Soft X-Rays Print A team of scientists has used x-ray diffraction microscopy at ALS Beamline 9.0.1 to make images of whole yeast cells, achieving the highest resolution-11 to 13 nanometers (billionths of a meter)-ever obtained with this method for biological specimens. Their success indicates that full 3-D tomography of whole cells at equivalent resolution should soon be possible. The National Center for X-Ray Tomography at ALS Beamline 2.1 images

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

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

    Lensless Imaging of Whole Biological Cells with Soft X-Rays Print A team of scientists has used x-ray diffraction microscopy at ALS Beamline 9.0.1 to make images of whole yeast cells, achieving the highest resolution-11 to 13 nanometers (billionths of a meter)-ever obtained with this method for biological specimens. Their success indicates that full 3-D tomography of whole cells at equivalent resolution should soon be possible. The National Center for X-Ray Tomography at ALS Beamline 2.1 images

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

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

    Lensless Imaging of Whole Biological 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 microscopy at ALS Beamline 9.0.1 to make images of whole yeast cells, achieving the highest resolution-11 to 13 nanometers (billionths of a meter)-ever obtained with this method for biological specimens. Their success indicates that full 3-D tomography of whole cells at equivalent resolution

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

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

    Lensless Imaging of Whole Biological Cells with Soft X-Rays Print A team of scientists has used x-ray diffraction microscopy at ALS Beamline 9.0.1 to make images of whole yeast cells, achieving the highest resolution-11 to 13 nanometers (billionths of a meter)-ever obtained with this method for biological specimens. Their success indicates that full 3-D tomography of whole cells at equivalent resolution should soon be possible. The National Center for X-Ray Tomography at ALS Beamline 2.1 images

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

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

    Lensless Imaging of Whole Biological Cells with Soft X-Rays Print A team of scientists has used x-ray diffraction microscopy at ALS Beamline 9.0.1 to make images of whole yeast cells, achieving the highest resolution-11 to 13 nanometers (billionths of a meter)-ever obtained with this method for biological specimens. Their success indicates that full 3-D tomography of whole cells at equivalent resolution should soon be possible. The National Center for X-Ray Tomography at ALS Beamline 2.1 images

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

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

    Lensless Imaging of Whole Biological Cells with Soft X-Rays Print A team of scientists has used x-ray diffraction microscopy at ALS Beamline 9.0.1 to make images of whole yeast cells, achieving the highest resolution-11 to 13 nanometers (billionths of a meter)-ever obtained with this method for biological specimens. Their success indicates that full 3-D tomography of whole cells at equivalent resolution should soon be possible. The National Center for X-Ray Tomography at ALS Beamline 2.1 images

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

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

    Lensless Imaging of Whole Biological Cells with Soft X-Rays Print A team of scientists has used x-ray diffraction microscopy at ALS Beamline 9.0.1 to make images of whole yeast cells, achieving the highest resolution-11 to 13 nanometers (billionths of a meter)-ever obtained with this method for biological specimens. Their success indicates that full 3-D tomography of whole cells at equivalent resolution should soon be possible. The National Center for X-Ray Tomography at ALS Beamline 2.1 images

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

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

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

    2011-05-01

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

  7. DISCOVERY OF AN EXTENDED X-RAY JET IN AP LIBRAE

    SciTech Connect (OSTI)

    Kaufmann, S.; Wagner, S. J.; Tibolla, O.

    2013-10-20

    Chandra observations of the low-energy-peaked BL Lac object (LBL) AP Librae (AP Lib) revealed the clear discovery of a non-thermal X-ray jet. AP Lib is the first LBL with an extended non-thermal X-ray jet that shows emission into the very high energy range. The X-ray jet has an extension of ?15''(? 14 kpc). The X-ray jet morphology is similar to the radio jet observed with Very Large Array at 1.36 GHz emerging in the southeast direction and bends by 50 at a distance of 12'' toward the northeast. The intensity profiles of the X-ray emission studied are consistent with those found in the radio range. The spectral analysis reveals that the X-ray spectra of the core and jet region are both inverse-Compton-(IC)-dominated. This adds to a still small sample of BL Lac objects whose X-ray jets are IC-dominated and thus more similar to the high-luminosity Fanaroff-Riley II sources than to the low-luminosity Fanaroff-Riley I objects, which are usually considered to be the parent population of BL Lac objects.

  8. Phase-contrast imaging using ultrafast x-rays in laser-shocked materials

    SciTech Connect (OSTI)

    Workman, Jonathan B; Cobble, James A; Flippo, Kirk; Gautier, Donald C; Montgomery, David S; Offermann, Dustin T

    2010-01-01

    High-energy x-rays, > 10-keV, can be efficiently produced from ultrafast laser target interactions with many applications to dense target materials in Inertial Confinement Fusion (ICF) and High-Energy Density Physics (HEDP). These same x-rays can also be applied to measurements of low-density materials inside high-density hohlraum environments. In the experiments presented, high-energy x-ray images of laser-shocked polystyrene are produced through phase contrast imaging. The plastic targets are nominally transparent to traditional x-ray absorption but show detailed features in regions of high density gradients due to refractive effects often called phase contrast imaging. The 200-TW Trident laser is used both to produce the x-ray source and to shock the polystyrene target. X-rays at 17-keV produced from 2-ps, 100-J laser interactions with a 12-micron molybdenum wire are used to produce a small source size, required for optimizing refractive effects. Shocks are driven in the 1-mm thick polystyrene target using 2-ns, 250-J, 532-nm laser drive with phase plates. X-ray images of shocks compare well to 1-D hydro calculations, HELIOS-CR.

  9. X-ray photonic microsystems for the manipulation of synchrotron light

    SciTech Connect (OSTI)

    Mukhopadhyay, D.; Walko, D. A.; Jung, I. W.; Schwartz, C. P.; Wang, Jin; López, D.; Shenoy, G. K.

    2015-05-05

    In this study, photonic microsystems played an essential role in the development of integrated photonic devices, thanks to their unique spatiotemporal control and spectral shaping capabilities. Similar capabilities to markedly control and manipulate X-ray radiation are highly desirable but practically impossible due to the massive size of the silicon single-crystal optics currently used. Here we show that micromechanical systems can be used as X-ray optics to create and preserve the spatial, temporal and spectral correlation of the X-rays. We demonstrate that, as X-ray reflective optics they can maintain the wavefront properties with nearly 100% reflectivity, and as a dynamic diffractive optics they can generate nanosecond time windows with over 100-kHz repetition rates. Since X-ray photonic microsystems can be easily incorporated into lab-based and next-generation synchrotron X-ray sources, they bring unprecedented design flexibility for future dynamic and miniature X-ray optics for focusing, wavefront manipulation, multicolour dispersion, and pulse slicing.

  10. Quantitative determination of mineral composition by powder X-ray diffraction

    DOE Patents [OSTI]

    Pawloski, Gayle A.

    1986-01-01

    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.

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

    DOE Patents [OSTI]

    Pawloski, G.A.

    1984-08-10

    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.

  12. Sample holder for X-ray diffractometry

    DOE Patents [OSTI]

    Hesch, Victor L.

    1992-01-01

    A sample holder for use with X-ray diffractometers with the capability to rotate the sample, as well as to adjust the position of the sample in the x, y, and z directions. Adjustment in the x direction is accomplished through loosening set screws, moving a platform, and retightening the set screws. Motion translators are used for adjustment in the y and z directions. An electric motor rotates the sample, and receives power from the diffractometer.

  13. Ultrashort x-ray backlighters and applications

    SciTech Connect (OSTI)

    Umstadter, D., University of Michigan

    1997-08-01

    Previously, using ultrashort laser pulses focused onto solid targets, we have experimentally studied a controllable ultrafast broadband radiation source in the extreme ultraviolet for time-resolved dynamical studies in ultrafast science [J. Workman, A. Maksimchuk, X. Llu, U. Ellenberger, J. S. Coe, C.-Y. Chien, and D. Umstadter, ``Control of Bright Picosecond X-Ray Emission from Intense Sub- Picosecond Laser-Plasma Interactions,`` Phys. Rev. Lett. 75, 2324 (1995)]. Once armed with a bright ultrafast broadband continuum x-ray source and appropriate detectors, we used the source as a backlighter to study a remotely produced plasma. The application of the source to a problem relevant to high-density matter completes the triad: creating and controlling, efficiently detecting, and applying the source. This work represented the first use of an ultrafast laser- produced x-ray source as a time-resolving probe in an application relevant to atomic, plasma and high-energy-density matter physics. Using the x-ray source as a backlighter, we adopted a pump-probe geometry to investigate the dynamic changes in electronic structure of a thin metallic film as it is perturbed by an ultrashort laser pulse. Because the laser deposits its energy in a skin depth of about 100 {Angstrom} before expansion occurs, up to gigabar pressure shock waves lasting picosecond in duration have been predicted to form in these novel plasmas. This raises the possibility of studying high- energy-density matter relevant to inertial confinement fusion (ICF) and astrophysics in small-scale laboratory experiments. In the past, time-resolved measurements of K-edge shifts in plasmas driven by nanosecond pulses have been used to infer conditions in highly compressed materials. In this study, we used 100-fs laser pulses to impulsively drive shocks into a sample (an untamped 1000 {Angstrom} aluminum film on 2000 {Angstrom} of parylene-n), measuring L-edge shifts.

  14. X-ray diffraction study of Penicillium Vitale catalase in the complex with aminotriazole

    SciTech Connect (OSTI)

    Borovik, A. A.; Grebenko, A. I.; Melik-Adamyan, V. R.

    2011-07-15

    The three-dimensional structure of the enzyme catalase from Penicillium vitale in a complex with the inhibitor aminotriazole was solved and refined by protein X-ray crystallography methods. An analysis of the three-dimensional structure of the complex showed that the inhibition of the enzyme occurs as a result of the covalent binding of aminotriazole to the amino-acid residue His64 in the active site of the enzyme. An investigation of the three-dimensional structure of the complex resulted in the amino-acid residues being more precisely identified. The binding sites of saccharide residues and calcium ions in the protein molecule were found.

  15. SIMULTANEOUS X-RAY AND ULTRAVIOLET OBSERVATIONS OF THE SW SEXTANTIS STAR DW URSAE MAJORIS

    SciTech Connect (OSTI)

    Hoard, D. W.; Wachter, S.; Lu, Ting-Ni; Knigge, Christian; Homer, Lee; Szkody, Paula; Still, M.; Long, Knox S.; Dhillon, V. S.

    2010-11-15

    We present the first pointed X-ray observation of DW Ursae Majoris, a novalike cataclysmic variable (CV) and one of the archetype members of the SW Sextantis class, obtained with the XMM-Newton satellite. These data provide the first detailed look at an SW Sex star in the X-ray regime (with previous X-ray knowledge of the SW Sex stars limited primarily to weak or non-detections in the ROSAT All Sky Survey). It is also one of only a few XMM-Newton observations (to date) of any high mass transfer rate novalike CV, and the only one in the evolutionarily important 3-4 hr orbital period range. The observed X-ray spectrum of DW UMa is very soft, with {approx}95% of the detected X-ray photons at energies <2 keV. The spectrum can be fit equally well by a one-component cooling flow model, with a temperature range of 0.2-3.5 keV, or a two-component, two-temperature thermal plasma model, containing hard ({approx}5-6 keV) and soft ({approx}0.8 keV) components. The X-ray light curve of DW UMa shows a likely partial eclipse, implying X-ray reprocessing in a vertically extended region, and an orbital modulation, implying a structural asymmetry in the X-ray reprocessing site (e.g., it cannot be a uniform corona). We also obtained a simultaneous near-ultraviolet light curve of DW UMa using the Optical Monitor on XMM-Newton. This light curve is similar in appearance to published optical-UV light curves of DW UMa and shows a prominent deep eclipse. Regardless of the exact nature of the X-ray reprocessing site in DW UMa, the lack of a prominent hard X-ray total eclipse and very low fraction of high energy X-rays point to the presence of an optically and geometrically thick accretion disk that obscures the boundary layer and modifies the X-ray spectrum emitted near the white dwarf.

  16. Near optimal energy selective x-ray imaging system performance with simple detectors

    SciTech Connect (OSTI)

    Alvarez, Robert E.

    2010-02-15

    Purpose: This article describes a method to achieve near optimal performance with low energy resolution detectors. Tapiovaara and Wagner [Phys. Med. Biol. 30, 519-529 (1985)] showed that an energy selective x-ray system using a broad spectrum source can produce images with a larger signal to noise ratio (SNR) than conventional systems using energy integrating or photon counting detectors. They showed that there is an upper limit to the SNR and that it can be achieved by measuring full spectrum information and then using an optimal energy dependent weighting. Methods: A performance measure is derived by applying statistical detection theory to an abstract vector space of the line integrals of the basis set coefficients of the two function approximation to the x-ray attenuation coefficient. The approach produces optimal results that utilize all the available energy dependent data. The method can be used with any energy selective detector and is applied not only to detectors using pulse height analysis (PHA) but also to a detector that simultaneously measures the total photon number and integrated energy, as discussed by Roessl et al. [Med. Phys. 34, 959-966 (2007)]. A generalization of this detector that improves the performance is introduced. A method is described to compute images with the optimal SNR using projections in a ''whitened'' vector space transformed so the noise is uncorrelated and has unit variance in both coordinates. Material canceled images with optimal SNR can also be computed by projections in this space. Results: The performance measure is validated by showing that it provides the Tapiovaara-Wagner optimal results for a detector with full energy information and also a conventional detector. The performance with different types of detectors is compared to the ideal SNR as a function of x-ray tube voltage and subject thickness. A detector that combines two bin PHA with a simultaneous measurement of integrated photon energy provides near ideal

  17. Biological Imaging by Soft X-Ray Diffraction Microscopy

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

    Biological Imaging by Soft X-Ray Diffraction Microscopy Print Electron and x-ray microscopes are a valuable tool for both the life and materials sciences, but they are limited in...

  18. X-Ray Diffraction Microscopy of Magnetic Structures

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

    X-Ray Diffraction Microscopy of Magnetic Structures Print science brief icon Scientists working at ALS Beamline 12.0.2.2 have demonstrated a new x-ray technique for producing...

  19. Ambient Pressure Photoelectron Spectroscopy Using Soft X-ray...

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

    Ambient Pressure Photoelectron Spectroscopy Using Soft X-ray and Hard X-ray, and its applications in electrochemistry Friday, December 14, 2012 - 3:30pm SSRL, Bldg. 137, room 322...

  20. Sector 3 : High Resolution X-ray Scattering | Advanced Photon...

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

    & workshops IXN Group Useful Links Current APS status ESAF System GUP System X-Ray Science Division My APS Portal Sector 3 : High Resolution X-ray Scattering Sector 3 is...

  1. Inelastic X-ray and Nuclear Resonant Scattering | Advanced Photon...

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

    XSD-IXN XSD-IXN Home Staff Inelastic X-ray and Nuclear Resonant Scattering The Inelastic X-ray and Nuclear Resonant Scattering group operates beamlines at APS Sectors 3, 9 and 30....

  2. X-ray Science Division (XSD) | Advanced Photon Source

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

    XSD Groups XSD Safety and Training XSD Strategic Plan XSD Visitor Program XSD Intranet X-ray Science Division (XSD) XSD enables world-class research using x-rays by developing...

  3. ALS X-Rays Shine a New Light on Catalysis

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

    ALS X-Rays Shine a New Light on Catalysis ALS X-Rays Shine a New Light on Catalysis Print Thursday, 21 May 2015 11:16 Electrocatalysts are responsible for expediting reactions in...

  4. Enabling X-ray free electron laser crystallography for challenging...

    Office of Scientific and Technical Information (OSTI)

    Enabling X-ray free electron laser crystallography for challenging biological systems from a limited number of crystals Citation Details In-Document Search Title: Enabling X-ray ...

  5. NIF and OMEGA X-Ray Environments Summary (Technical Report) ...

    Office of Scientific and Technical Information (OSTI)

    NIF and OMEGA X-Ray Environments Summary Citation Details In-Document Search Title: NIF and OMEGA X-Ray Environments Summary Abstract not provided. Authors: Fournier, K. B. 1 + ...

  6. A Spatially Resolving X-ray Crystal Spectrometer for Measurement...

    Office of Scientific and Technical Information (OSTI)

    A Spatially Resolving X-ray Crystal Spectrometer for Measurement of Ion-temperature and ... Citation Details In-Document Search Title: A Spatially Resolving X-ray Crystal ...

  7. Crystallization and preliminary X-ray crystallographic studies...

    Office of Scientific and Technical Information (OSTI)

    X-ray crystallographic studies of Drep-3, a DFF-related protein from Drosophila melanogaster Citation Details In-Document Search Title: Crystallization and preliminary X-ray ...

  8. Structure and Reactivity of X-ray Amorphous Uranyl Peroxide,...

    Office of Scientific and Technical Information (OSTI)

    Published Article: Structure and Reactivity of X-ray Amorphous Uranyl Peroxide, U 2 O 7 Prev Next Title: Structure and Reactivity of X-ray Amorphous Uranyl Peroxide, U 2 O 7 ...

  9. X-ray imaging of Nonlinear Resonant Gyrotropic Magnetic Vortex...

    Office of Scientific and Technical Information (OSTI)

    X-ray imaging of Nonlinear Resonant Gyrotropic Magnetic Vortex Core Motion in Circular Permalloy Disks Citation Details In-Document Search Title: X-ray imaging of Nonlinear ...

  10. X-ray photonic microsystems for the manipulation of synchrotron...

    Office of Scientific and Technical Information (OSTI)

    (MEMS) when combined with micro-optics have found a wide range of photonics applications. ... for X-rays, a new generation of photonics microsystems for X-ray wavelengths will ...

  11. Biological Imaging by Soft X-Ray Diffraction Microscopy

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

    Biological Imaging by Soft X-Ray Diffraction Microscopy Print Electron and x-ray microscopes are a valuable tool for both the life and materials sciences, but they are limited in ...

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

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

    While x-ray transparency will have immediate applications at x-ray light sources, the important result is that the findings lay a foundation for a broader spectrum of applications. ...

  13. X-Ray Diffraction Microscopy of Magnetic Structures

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

    X-Ray Diffraction Microscopy of Magnetic Structures Print science brief icon Scientists working at ALS Beamline 12.0.2.2 have demonstrated a new x-ray technique for producing ...

  14. NIF and OMEGA X-Ray Environments Summary (Technical Report) ...

    Office of Scientific and Technical Information (OSTI)

    NIF and OMEGA X-Ray Environments Summary Citation Details In-Document Search Title: NIF and OMEGA X-Ray Environments Summary You are accessing a document from the Department of ...

  15. 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. H.; et al

    2006-01-01

    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

  16. Biological Imaging by Soft X-Ray Diffraction Microscopy

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

    Biological Imaging by Soft X-Ray Diffraction Microscopy Print Electron and x-ray microscopes are a valuable tool for both the life and materials sciences, but they are limited in their ability to image with nanometer-scale resolution in three dimensions nonperiodic objects that are several microns in size. To fill this gap, the technique of coherent x-ray diffraction imaging now under development takes advantage of the penetrating power of x rays while simultaneously removing the limitations

  17. Biological Imaging by Soft X-Ray Diffraction Microscopy

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

    Biological Imaging by Soft X-Ray Diffraction Microscopy Print Electron and x-ray microscopes are a valuable tool for both the life and materials sciences, but they are limited in their ability to image with nanometer-scale resolution in three dimensions nonperiodic objects that are several microns in size. To fill this gap, the technique of coherent x-ray diffraction imaging now under development takes advantage of the penetrating power of x rays while simultaneously removing the limitations

  18. Biological Imaging by Soft X-Ray Diffraction Microscopy

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

    Biological Imaging by Soft X-Ray Diffraction Microscopy Print Electron and x-ray microscopes are a valuable tool for both the life and materials sciences, but they are limited in their ability to image with nanometer-scale resolution in three dimensions nonperiodic objects that are several microns in size. To fill this gap, the technique of coherent x-ray diffraction imaging now under development takes advantage of the penetrating power of x rays while simultaneously removing the limitations

  19. Biological Imaging by Soft X-Ray Diffraction Microscopy

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

    Biological Imaging by Soft X-Ray Diffraction Microscopy Print Electron and x-ray microscopes are a valuable tool for both the life and materials sciences, but they are limited in their ability to image with nanometer-scale resolution in three dimensions nonperiodic objects that are several microns in size. To fill this gap, the technique of coherent x-ray diffraction imaging now under development takes advantage of the penetrating power of x rays while simultaneously removing the limitations

  20. Biological Imaging by Soft X-Ray Diffraction Microscopy

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

    Biological Imaging by Soft X-Ray Diffraction Microscopy Print Electron and x-ray microscopes are a valuable tool for both the life and materials sciences, but they are limited in their ability to image with nanometer-scale resolution in three dimensions nonperiodic objects that are several microns in size. To fill this gap, the technique of coherent x-ray diffraction imaging now under development takes advantage of the penetrating power of x rays while simultaneously removing the limitations

  1. Biological Imaging by Soft X-Ray Diffraction Microscopy

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

    Biological Imaging by Soft X-Ray Diffraction Microscopy Print Electron and x-ray microscopes are a valuable tool for both the life and materials sciences, but they are limited in their ability to image with nanometer-scale resolution in three dimensions nonperiodic objects that are several microns in size. To fill this gap, the technique of coherent x-ray diffraction imaging now under development takes advantage of the penetrating power of x rays while simultaneously removing the limitations

  2. Biological Imaging by Soft X-Ray Diffraction Microscopy

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

    Biological Imaging by Soft X-Ray Diffraction Microscopy Print Electron and x-ray microscopes are a valuable tool for both the life and materials sciences, but they are limited in their ability to image with nanometer-scale resolution in three dimensions nonperiodic objects that are several microns in size. To fill this gap, the technique of coherent x-ray diffraction imaging now under development takes advantage of the penetrating power of x rays while simultaneously removing the limitations

  3. Biological Imaging by Soft X-Ray Diffraction Microscopy

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

    Biological Imaging by Soft X-Ray Diffraction Microscopy Print Electron and x-ray microscopes are a valuable tool for both the life and materials sciences, but they are limited in their ability to image with nanometer-scale resolution in three dimensions nonperiodic objects that are several microns in size. To fill this gap, the technique of coherent x-ray diffraction imaging now under development takes advantage of the penetrating power of x rays while simultaneously removing the limitations

  4. Novel detector design for reducing intercell x-ray cross-talk in the variable resolution x-ray CT scanner: A Monte Carlo study

    SciTech Connect (OSTI)

    Arabi, Hosein; Asl, Ali Reza Kamali; Ay, Mohammad Reza; Zaidi, Habib

    2011-03-15

    Purpose: The variable resolution x-ray (VRX) CT scanner provides substantial improvement in the spatial resolution by matching the scanner's field of view (FOV) to the size of the object being imaged. Intercell x-ray cross-talk is one of the most important factors limiting the spatial resolution of the VRX detector. In this work, a new cell arrangement in the VRX detector is suggested to decrease the intercell x-ray cross-talk. The idea is to orient the detector cells toward the opening end of the detector. Methods: Monte Carlo simulations were used for performance assessment of the oriented cell detector design. Previously published design parameters and simulation results of x-ray cross-talk for the VRX detector were used for model validation using the GATE Monte Carlo package. In the first step, the intercell x-ray cross-talk of the actual VRX detector model was calculated as a function of the FOV. The obtained results indicated an optimum cell orientation angle of 28 deg. to minimize the x-ray cross-talk in the VRX detector. Thereafter, the intercell x-ray cross-talk in the oriented cell detector was modeled and quantified. Results: The intercell x-ray cross-talk in the actual detector model was considerably high, reaching up to 12% at FOVs from 24 to 38 cm. The x-ray cross-talk in the oriented cell detector was less than 5% for all possible FOVs, except 40 cm (maximum FOV). The oriented cell detector could provide considerable decrease in the intercell x-ray cross-talk for the VRX detector, thus leading to significant improvement in the spatial resolution and reduction in the spatial resolution nonuniformity across the detector length. Conclusions: The proposed oriented cell detector is the first dedicated detector design for the VRX CT scanners. Application of this concept to multislice and flat-panel VRX detectors would also result in higher spatial resolution.

  5. First-principles calculation of principal Hugoniot and K-shell X-ray absorption spectra for warm dense KCl

    SciTech Connect (OSTI)

    Zhao, Shijun; Zhang, Shen; Kang, Wei; Li, Zi; Zhang, Ping; He, Xian-Tu

    2015-06-15

    Principal Hugoniot and K-shell X-ray absorption spectra of warm dense KCl are calculated using the first-principles molecular dynamics (FPMD) method. Evolution of electronic structures as well as the influence of the approximate description of ionization on pressure (caused by the underestimation of the energy gap between conduction bands and valence bands) in the first-principles method are illustrated by the calculation. It is shown that approximate description of ionization in FPMD has small influence on Hugoniot pressure due to mutual compensation of electronic kinetic pressure and virial pressure. The calculation of X-ray absorption spectra shows that the band gap of KCl persists after the pressure ionization of the 3p electrons of Cl and K taking place at lower energy, which provides a detailed understanding to the evolution of electronic structures of warm dense matter.

  6. New Zone Plate for Soft X-Ray Microscopy at 15-nm Spatial Resolution

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

    New Zone Plate for Soft X-Ray Microscopy at 15-nm Spatial Resolution Print Analytical tools that combine spatial resolution with elemental and chemical identification at the nanometer scale along with large penetration depth are indispensable for the life and physical sciences. The XM-1 soft x-ray microscope at the ALS produces images that not only reveal structures but can identify their chemical elements and measure magnetic and other properties as well. Now a new method for creating optical

  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.; Vales, V.; Endres, J.; Holy, V.; Buljan, M.; Bernstorff, S.

    2013-01-14

    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. New Zone Plate for Soft X-Ray Microscopy at 15-nm Spatial Resolution

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

    New Zone Plate for Soft X-Ray Microscopy at 15-nm Spatial Resolution Print Analytical tools that combine spatial resolution with elemental and chemical identification at the nanometer scale along with large penetration depth are indispensable for the life and physical sciences. The XM-1 soft x-ray microscope at the ALS produces images that not only reveal structures but can identify their chemical elements and measure magnetic and other properties as well. Now a new method for creating optical

  9. New Zone Plate for Soft X-Ray Microscopy at 15-nm Spatial Resolution

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

    New Zone Plate for Soft X-Ray Microscopy at 15-nm Spatial Resolution Print Analytical tools that combine spatial resolution with elemental and chemical identification at the nanometer scale along with large penetration depth are indispensable for the life and physical sciences. The XM-1 soft x-ray microscope at the ALS produces images that not only reveal structures but can identify their chemical elements and measure magnetic and other properties as well. Now a new method for creating optical

  10. Femtosecond laser-electron x-ray source

    DOE Patents [OSTI]

    Hartemann, Frederic V.; Baldis, Hector A.; Barty, Chris P.; Gibson, David J.; Rupp, Bernhard

    2004-04-20

    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.

  11. 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.

  12. SOFT X-RAY IRRADIATION OF PURE CARBON MONOXIDE INTERSTELLAR ICE ANALOGUES

    SciTech Connect (OSTI)

    Ciaravella, A.; Candia, R.; Collura, A.; Jimenez-Escobar, A.; Munoz Caro, G. M.; Cecchi-Pestellini, C.; Giarrusso, S.; Barbera, M.

    2012-02-10

    There is an increasing evidence for the existence of large organic molecules in the interstellar and circumstellar medium. Very few among such species are readily formed in conventional gas-phase chemistry under typical conditions of interstellar clouds. Attention has therefore focused on interstellar ices as a potential source of these relatively complex species. Laboratory experiments show that irradiation of interstellar ice analogues by fast particles or ultraviolet radiation can induce significant chemical complexity. However, stars are sources of intense X-rays at almost every stage of their formation and evolution. Such radiation may thus provide chemical changes in regions where ultraviolet radiation is severely inhibited. After H{sub 2}O, CO is often the most abundant component of icy grain mantles in dense interstellar clouds and circumstellar disks. In this work we present irradiation of a pure carbon monoxide ice using a soft X-ray spectrum peaked at 0.3 keV. Analysis of irradiated samples shows formation of CO{sub 2}, C{sub 2}O, C{sub 3}O{sub 2}, C{sub 3}, C{sub 4}O, and CO{sub 3}/C{sub 5}. Comparison of X-rays and ultraviolet irradiation experiments, of the same energy dose, shows that X-rays are more efficient than ultraviolet radiation in producing new species. With the exception of CO{sub 2}, X-ray photolysis induces formation of a larger number of products with higher abundances, e.g., C{sub 3}O{sub 2} column density is about one order of magnitude higher in the X-ray experiment. To our knowledge this is the first report on X-ray photolysis of CO ices. The present results show that X-ray irradiation represents an efficient photo-chemical way to convert simple ices to more complex species.

  13. Low-level determination of plutonium by gamma and L x-ray spectroscopy

    SciTech Connect (OSTI)

    Nitsche, H.; Gatti, R.C.; Lee, S.C.

    1991-04-01

    we have developed an analytical method for detection of {sup 239}Pu in aqueous samples at concentrations as low as 10{sup {minus}10} M. This nuclear counting technique utilizes the uranium L X-rays, which follow the alpha decay of plutonium. Because L X-rays are specific for the element and not for the individual isotopes, the isotopic composition of the plutonium sample must be known. The counting efficiency in the 11--23 keV range is determined from a plutonium standard, and the concentration of the sample is then calculated from the L X-ray count and the isotopic composition. The total L X-ray count is corrected for possible contributions from other radionuclides present as impurities by measuring the low-energy gamma spectrum for each contaminant to establish specific photon/X-ray ratios. The ratios are important when {sup 241}Pu and {sup 242}Pu are measured, because the respective decay chain members produce non-U L X-rays. This new method can replace the use of labor-intensive radiochemical separation techniques and elaborate activation methods for analysis of {sup 239}Pu in aqueous samples. It is also applicable for assaying plutonium in liquid wastes that pose possible hazards to the environment.

  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 M; Giglia, Angelo; Mahne, Nicola; Nannarone, Stefano

    2011-04-05

    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 is independent of the film thickness.

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

    SciTech Connect (OSTI)

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

    2014-07-15

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

  16. 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

    2011-01-12

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

  17. 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

    2010-04-20

    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 α-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

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

    SciTech Connect (OSTI)

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

    2010-04-20

    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.

  19. Beyond crystallography: Diffractive imaging using coherent x-ray light sources

    SciTech Connect (OSTI)

    Miao, J.; Ishikawa, T.; Robinson, I. K.; Murnane, M. M.

    2015-04-30

    X-ray crystallography has been central to the development of many fields of science over the past century. It has now matured to a point that as long as good-quality crystals are available, their atomic structure can be routinely determined in three dimensions. However, many samples in physics, chemistry, materials science, nanoscience, geology, and biology are noncrystalline, and thus their three-dimensional structures are not accessible by traditional x-ray crystallography. Overcoming this hurdle has required the development of new coherent imaging methods to harness new coherent x-ray light sources. Here we review the revolutionary advances that are transforming x-ray sources and imaging in the 21st century.

  20. Different X-ray spectral evolution for black hole X-ray binaries in dual tracks of radio-X-ray correlation

    SciTech Connect (OSTI)

    Cao, Xiao-Feng; Wu, Qingwen; Dong, Ai-Jun

    2014-06-10

    Recently, an 'outlier' track of radio-X-ray correlation was found, which is much steeper than the former universal correlation, where dual tracks were speculated to be triggered by different accretion processes. In this work, we test this issue by exploring hard X-ray spectral evolution in four black-hole X-ray binaries with multiple, quasi-simultaneous radio and X-ray observations. First, we find that hard X-ray photon indices, Γ, are negatively and positively correlated with X-ray fluxes when the X-ray flux, F{sub 3-9} {sub keV}, is below and above a critical flux, F{sub X,} {sub crit}, which are consistent with predictions of the advection-dominated accretion flow and the disk-corona model, respectively. Second, and most importantly, we find that the radio-X-ray correlations are also clearly different when the X-ray fluxes are higher and lower than the critical flux as defined by X-ray spectral evolution. The data points with F{sub 3-9} {sub keV} ≳ F{sub X,} {sub crit} have a steeper radio-X-ray correlation (F{sub X}∝F{sub R}{sup b} and b ∼ 1.1-1.4), which roughly forms the ''outlier'' track. However, the data points with anti-correlation of Γ – F{sub 3-9} {sub keV} either stay in the universal track with b ∼ 0.61 or stay in the transition track (from the universal to 'outlier' tracks or vice versa). Therefore, our results support that the universal and ''outlier'' tracks of radio-X-ray correlations are regulated by radiatively inefficient and radiatively efficient accretion model, respectively.

  1. Achieving hard X-ray nanofocusing using a wedged multilayer Laue lens

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

    Huang, Xiaojing; Conley, Raymond; Bouet, Nathalie; Zhou, Juan; Macrander, Albert; Maser, Jorg; Yan, Hanfei; Nazaretski, Evgeny; Lauer, Kenneth; Harder, Ross; et al

    2015-05-04

    We report on the fabrication and the characterization of a wedged multilayer Laue lens for x-ray nanofocusing. The lens was fabricated using a sputtering deposition technique, in which a specially designed mask was employed to introduce a thickness gradient in the lateral direction of the multilayer. X-ray characterization shows an efficiency of 27% and a focus size of 26 nm at 14.6 keV, in a good agreement with theoretical calculations. These results indicate that the desired wedging is achieved in the fabricated structure. We anticipate that continuous development on wedged MLLs will advance x-ray nanofocusing optics to new frontiers andmoreenrich capabilities and opportunities for hard X-ray microscopy.less

  2. Achieving Hard X-ray Nanofocusing Using a Wedged Multilayer Laue Lens

    SciTech Connect (OSTI)

    Huang, Xiaojing; Conley, Raymond; Bouet, Nathalie; Zhou, Juan; Macrander, Albert; Maser, Jorg; Yan, Hanfei; Nazaretski, Evgeny; Lauer, Kenneth; Harder, Ross; Robinson, Ian K.; Kalbfleisch, Sebastian; Chu, Yong S.

    2015-05-04

    Here, we report on the fabrication and the characterization of a wedged multilayer Laue lens for x-ray nanofocusing. The lens was fabricated using a sputtering deposition technique, in which a specially designed mask was employed to introduce a thickness gradient in the lateral direction of the multilayer. X-ray characterization shows an efficiency of 27% and a focus size of 26 nm at 14.6 keV, in a good agreement with theoretical calculations. Our results indicate that the desired wedging is achieved in the fabricated structure. Furthermore, we anticipate that continuous development on wedged MLLs will advance x-ray nanofocusing optics to new frontiers and enrich capabilities and opportunities for hard X-ray microscopy.

  3. X-Ray Imaging Crystal Spectrometer for Extended X-Ray Sources

    SciTech Connect (OSTI)

    Bitter, Manfred L.; Fraekel, Benjamin; Gorman, James L.; Hill, Kenneth W.; Roquemore, Lane A.; Stodiek, Wolfgang; Goeler, Schweickhard von

    1999-05-01

    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 tokamak fusion experiment to provide spatially and temporally resolved data on plasma parameters such as ion temperature, toroidal and poloidal rotation, electron temperature, impurity ion charge-state distributions, and impurity transport. The imaging properties of these spherically or toroidally curved crystals provide both spectrally and spatially resolved X-ray data from the plasma using only one small spherically or toroidally curved crystal, thus eliminating the requirement for a large array of crystal spectrometers and the need to cross-calibrate the various crystals.

  4. Re-refinement from deposited X-ray data can deliver improved models for most PDB entries

    SciTech Connect (OSTI)

    Joosten, Robbie P.; Womack, Thomas; Vriend, Gert; Bricogne, Gérard

    2009-02-01

    An evaluation of validation and real-space intervention possibilities for improving existing automated (re-)refinement methods. The deposition of X-ray data along with the customary structural models defining PDB entries makes it possible to apply large-scale re-refinement protocols to these entries, thus giving users the benefit of improvements in X-ray methods that have occurred since the structure was deposited. Automated gradient refinement is an effective method to achieve this goal, but real-space intervention is most often required in order to adequately address problems detected by structure-validation software. In order to improve the existing protocol, automated re-refinement was combined with structure validation and difference-density peak analysis to produce a catalogue of problems in PDB entries that are amenable to automatic correction. It is shown that re-refinement can be effective in producing improvements, which are often associated with the systematic use of the TLS parameterization of B factors, even for relatively new and high-resolution PDB entries, while the accompanying manual or semi-manual map analysis and fitting steps show good prospects for eventual automation. It is proposed that the potential for simultaneous improvements in methods and in re-refinement results be further encouraged by broadening the scope of depositions to include refinement metadata and ultimately primary rather than reduced X-ray data.

  5. When will low-contrast features be visible in a STEM X-ray spectrum image?

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

    Parish, Chad M.

    2015-02-03

    When will a small or low-contrast feature, such as an embedded second-phase particle, be visible in a scanning transmission electron microscopy (STEM) X-ray map? This work illustrates a computationally inexpensive method to simulate X-ray maps and spectrum images (SIs), based upon the equations of X-ray generation and detection. To particularize the general procedure, an example of nanostructured ferritic alloy (NFA) containing nm-sized Y2Ti2O7 embedded precipitates in ferritic stainless steel matrix is chosen. The proposed model produces physically appearing simulated SI data sets, which can either be reduced to X-ray dot maps or analyzed via multivariate statistical analysis. Comparison to NFAmore » X-ray maps acquired using three different STEM instruments match the generated simulations quite well, despite the large number of simplifying assumptions used. A figure of merit of electron dose multiplied by X-ray collection solid angle is proposed to compare feature detectability from one data set (simulated or experimental) to another. The proposed method can scope experiments that are feasible under specific analysis conditions on a given microscope. As a result, future applications, such as spallation proton–neutron irradiations, core-shell nanoparticles, or dopants in polycrystalline photovoltaic solar cells, are proposed.« less

  6. When will low-contrast features be visible in a STEM X-ray spectrum image?

    SciTech Connect (OSTI)

    Parish, Chad M.

    2015-02-03

    When will a small or low-contrast feature, such as an embedded second-phase particle, be visible in a scanning transmission electron microscopy (STEM) X-ray map? This work illustrates a computationally inexpensive method to simulate X-ray maps and spectrum images (SIs), based upon the equations of X-ray generation and detection. To particularize the general procedure, an example of nanostructured ferritic alloy (NFA) containing nm-sized Y2Ti2O7 embedded precipitates in ferritic stainless steel matrix is chosen. The proposed model produces physically appearing simulated SI data sets, which can either be reduced to X-ray dot maps or analyzed via multivariate statistical analysis. Comparison to NFA X-ray maps acquired using three different STEM instruments match the generated simulations quite well, despite the large number of simplifying assumptions used. A figure of merit of electron dose multiplied by X-ray collection solid angle is proposed to compare feature detectability from one data set (simulated or experimental) to another. The proposed method can scope experiments that are feasible under specific analysis conditions on a given microscope. As a result, future applications, such as spallation proton–neutron irradiations, core-shell nanoparticles, or dopants in polycrystalline photovoltaic solar cells, are proposed.

  7. HARD X-RAY OBSERVATIONS OF A JET AND ACCELERATED ELECTRONS IN THE CORONA

    SciTech Connect (OSTI)

    Glesener, Lindsay; Lin, R. P.; Krucker, Saem, E-mail: glesener@ssl.berkeley.edu [Space Science Laboratory, UC Berkeley, 7 Gauss Way, Berkeley, CA 94720 (United States)

    2012-07-20

    We report the first hard X-ray observation of a solar jet on the limb with flare footpoints occulted, so that faint emission from accelerated electrons in the corona can be studied in detail. In this event on 2003 August 21, RHESSI observed a double coronal hard X-ray source in the pre-impulsive phase at both thermal and nonthermal energies. In the impulsive phase, the first of two hard X-ray bursts consists of a single thermal/nonthermal source coinciding with the lower of the two earlier sources, and the second burst shows an additional nonthermal, elongated source, spatially and temporally coincident with the coronal jet. Analysis of the jet hard X-ray source shows that collisional losses by accelerated electrons can deposit enough energy to generate the jet. The hard X-ray time profile above 20 keV matches that of the accompanying Type III and broadband gyrosynchrotron radio emission, indicating both accelerated electrons escaping outward along the jet path and electrons trapped in the flare loop. The double coronal hard X-ray source, the open field lines indicated by Type III bursts, and the presence of a small post-flare loop are consistent with significant electron acceleration in an interchange reconnection geometry.

  8. X-ray computed tomography using curvelet sparse regularization

    SciTech Connect (OSTI)

    Wieczorek, Matthias Vogel, Jakob; Lasser, Tobias; Frikel, Jürgen; Demaret, Laurent; Eggl, Elena; Pfeiffer, Franz; Kopp, Felix; Noël, Peter B.

    2015-04-15

    Purpose: Reconstruction of x-ray computed tomography (CT) data remains a mathematically challenging problem in medical imaging. Complementing the standard analytical reconstruction methods, sparse regularization is growing in importance, as it allows inclusion of prior knowledge. The paper presents a method for sparse regularization based on the curvelet frame for the application to iterative reconstruction in x-ray computed tomography. Methods: In this work, the authors present an iterative reconstruction approach based on the alternating direction method of multipliers using curvelet sparse regularization. Results: Evaluation of the method is performed on a specifically crafted numerical phantom dataset to highlight the method’s strengths. Additional evaluation is performed on two real datasets from commercial scanners with different noise characteristics, a clinical bone sample acquired in a micro-CT and a human abdomen scanned in a diagnostic CT. The results clearly illustrate that curvelet sparse regularization has characteristic strengths. In particular, it improves the restoration and resolution of highly directional, high contrast features with smooth contrast variations. The authors also compare this approach to the popular technique of total variation and to traditional filtered backprojection. Conclusions: The authors conclude that curvelet sparse regularization is able to improve reconstruction quality by reducing noise while preserving highly directional features.

  9. Apparatus for monitoring X-ray beam alignment

    DOE Patents [OSTI]

    Steinmeyer, P.A.

    1991-10-08

    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.

  10. Apparatus for monitoring X-ray beam alignment

    DOE Patents [OSTI]

    Steinmeyer, Peter A.

    1991-10-08

    A self-contained, hand-held apparatus is provided for minitoring 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.

  11. RYLLA. [X-ray transport code

    SciTech Connect (OSTI)

    Hyde, R.A.

    1983-06-08

    This paper describes a computer code, RYLLA, which models the deposition of x-rays into thin metal slabs, and transports the resulting photoelectrons, finding the distribution of electrons leaving the slab from both the front and back surfaces. The slab must be homogeneous, but can contain a mixture of up to 5 different elements. Due to the short electron mean free path at low electron energies, RYLLA should be used only for studying thin slabs, roughly < 100 mg/cm/sup 2/ for low Z metals, and < 10 mg/cm/sup 2/ for high Z metals. X-ray energies should be in the range of 1 to 150 keV, as they are deposited only via photoionization and Compton scattering processes. Following photoionization, a hole exists in the electron cloud of the absorbing atom. This fills either by Auger or fluoresence, resulting in lower energy holes which are also filled. Fluoresence photons are transported and absorbed in the same manner as the primary photons, except that they are isotropically produced. Once all photons have been transported and absorbed, and all holes have been filled, a space- and energy-dependent electron source spectrum has been obtained. This is used in a discrete ordinate expansion solution of the 1-D transport equation, which gives the output electron spectra at the two slab surfaces. This paper discusses both the physics and coding of RYLLA. Examples of user input are given, as are some comparisons with other codes.

  12. A general theory of interference fringes in x-ray phase grating imaging

    SciTech Connect (OSTI)

    Yan, Aimin; Wu, Xizeng E-mail: liu@ou.edu; Liu, Hong E-mail: liu@ou.edu

    2015-06-15

    Purpose: The authors note that the concept of the Talbot self-image distance in x-ray phase grating interferometry is indeed not well defined for polychromatic x-rays, because both the grating phase shift and the fractional Talbot distances are all x-ray wavelength-dependent. For x-ray interferometry optimization, there is a need for a quantitative theory that is able to predict if a good intensity modulation is attainable at a given grating-to-detector distance. In this work, the authors set out to meet this need. Methods: In order to apply Fourier analysis directly to the intensity fringe patterns of two-dimensional and one-dimensional phase grating interferometers, the authors start their derivation from a general phase space theory of x-ray phase-contrast imaging. Unlike previous Fourier analyses, the authors evolved the Wigner distribution to obtain closed-form expressions of the Fourier coefficients of the intensity fringes for any grating-to-detector distance, even if it is not a fractional Talbot distance. Results: The developed theory determines the visibility of any diffraction order as a function of the grating-to-detector distance, the phase shift of the grating, and the x-ray spectrum. The authors demonstrate that the visibilities of diffraction orders can serve as the indicators of the underlying interference intensity modulation. Applying the theory to the conventional and inverse geometry configurations of single-grating interferometers, the authors demonstrated that the proposed theory provides a quantitative tool for the grating interferometer optimization with or without the Talbot-distance constraints. Conclusions: In this work, the authors developed a novel theory of the interference intensity fringes in phase grating x-ray interferometry. This theory provides a quantitative tool in design optimization of phase grating x-ray interferometers.

  13. ECLIPSE TIMINGS OF THE TRANSIENT LOW-MASS X-RAY BINARY EXO 0748-676. IV. THE ROSSI X-RAY TIMING EXPLORER ECLIPSES

    SciTech Connect (OSTI)

    Wolff, Michael T.; Ray, Paul S.; Wood, Kent S.; Hertz, Paul L. E-mail: Paul.Ray@nrl.navy.mil E-mail: Paul.Hertz@nasa.gov

    2009-07-01

    We report our complete database of X-ray eclipse timings of the low-mass X-ray binary EXO 0748-676 observed by the Rossi X-Ray Timing Explorer (RXTE) satellite. As of this writing we have accumulated 443 full X-ray eclipses, 392 of which have been observed with the Proportional Counter Array on RXTE. These include both observations where an eclipse was specifically targeted and those eclipses found in the RXTE data archive. Eclipse cycle count has been maintained since the discovery of the EXO 0748-676 system in 1985 February. We describe our observing and analysis techniques for each eclipse and describe improvements we have made since the last compilation by Wolff et al. The principal result of this paper is the database containing the timing results from a seven-parameter fit to the X-ray light curve for each observed eclipse along with the associated errors in the fitted parameters. Based on the standard O - C analysis, EXO 0748-676 has undergone four distinct orbital period epochs since its discovery. In addition, EXO 0748-676 shows small-scale events in the O - C curve that are likely due to short-lived changes in the secondary star.

  14. An X-ray IMAGING SURVEY OF QUASAR JETS: TESTING THE INVERSE COMPTON MODEL

    SciTech Connect (OSTI)

    Marshall, H. L.; Gelbord, J. M.; Schwartz, D. A.; Worrall, D. M.; Birkinshaw, M.; Murphy, D. W.; Godfrey, L.; Jauncey, D. L.; Lovell, J. E. J.; Perlman, E. S. E-mail: jgelbord@astro.psu.edu E-mail: D. Worrall@bristol.ac.uk E-mail: david.murphy@jpl.nasa.gov E-mail: David.Jauncey@csiro.au E-mail: eperlman@fit.edu

    2011-03-15

    We present results from continued Chandra X-ray imaging and spectroscopy of a flux-limited sample of flat spectrum radio-emitting quasars with jet-like extended structure. X-rays are detected from 24 of the 39 jets observed so far. We compute the distribution of {alpha} {sub rx}, the spectral index between the X-ray and radio bands, showing that it is broad, extending at least from 0.8 to 1.2. While there is a general trend that the radio brightest jets are detected most often, it is clear that predicting the X-ray flux from the radio knot flux densities is risky, so a shallow X-ray survey is the most effective means for finding jets that are X-ray bright. We test the model in which the X-rays result from inverse Compton (IC) scattering of cosmic microwave background (CMB) photons by relativistic electrons in the jet moving with a high bulk Lorentz factor nearly along the line of sight. Depending on how the jet magnetic fields vary with z, the observed X-ray to radio flux ratios do not follow the redshift dependence expected from the IC-CMB model. For a subset of our sample with known superluminal motion based on VLBI observations, we estimate the angle of the kiloparsec-scale jet to the line of sight by considering the additional information in the bends observed between parsec- and kiloparsec-scale jets. These angles are sometimes much smaller than estimates based on the IC-CMB model with a Lorentz factor of 15, indicating that these jets may decelerate significantly from parsec scales to kiloparsec scales.

  15. Magnetic circular dichroism in x-ray absorption and core-level photoemission

    SciTech Connect (OSTI)

    Tobin, J.G.; Waddill, G.D.; Gouder, T.H.; Colmenares, C.A.; Pappas, D.P.

    1993-03-17

    Here is reported observation of magnetic circular dichroism in both x-ray absorption and core-level photoemission of ultra thin magnetic films using circularly polarized x-rays. Iron films (1--4 ML) grown on a Cu(001) substrate at 150 K and magnetized perpendicular to the surface show dramatic changes in the L{sub 2,3} branching ratio for different x-ray polarizations. For linearly-polarized x-rays perpendicular to the magnetic axis of the sample the branching ratio was 0.75. For films {ge} 2 ML, this ratio varied from 0.64 to 0.85 for photon spin parallel and anti-parallel, respectively, to the magnetic axis. This effect was observed either by changing the x-ray helicity for a fixed magnetic axis, or by reversing the magnetic axis for a fixed x-ray helicity. Our observation can be analyzed within a simple one-electron picture, if the raw branching ratios are no so that the linear value becomes statistical Furthermore, warming the films to {approximately}300 K eliminated this effect, indicating a loss of magnetization in the film over a temperature range of {approximately}30 K. Finally, reversing the relative orientation of the photon spin and the magnetic axis from parallel to anti-parallel allowed measurement of the exchange splitting of the Fe 2p and 3p core levels which were found to be 0.3 eV and 0.2 eV. respectively. These results are consistent with earlier studies, but the use of off-plane circularly-polarized x-rays from a bending magnet monochromator offers {approximately}2 orders of magnitude greater intensity than typical spin-polarization measurements. Finally, we have performed preliminary x-ray absorption studies of UFe{sub 2}, demonstrating the feasibilty of MCD measurements in 5f as well as 3d materials.

  16. The energy dependence of lithium formate and alanine EPR dosimeters for medium energy x rays

    SciTech Connect (OSTI)

    Waldeland, Einar; Hole, Eli Olaug; Sagstuen, Einar; Malinen, Eirik

    2010-07-15

    Purpose: To perform a systematic investigation of the energy dependence of alanine and lilthium formate EPR dosimeters for medium energy x rays. Methods: Lithium formate and alanine EPR dosimeters were exposed to eight different x-ray beam qualities, with nominal potentials ranging from 50 to 200 kV. Following ionometry based on standards of absorbed dose to water, the dosimeters were given two different doses of approximately 3 and 6 Gy for each radiation quality, with three dosimeters for each dose. A reference series was also irradiated to three different dose levels at a {sup 60}Co unit. The dose to water energy response, that is, the dosimeter reading per absorbed dose to water relative to that for {sup 60}Co {gamma}-rays, was estimated for each beam quality. In addition, the energy response was calculated by Monte Carlo simulations and compared to the experimental energy response. Results: The experimental energy response estimates ranged from 0.89 to 0.94 and from 0.68 to 0.90 for lithium formate and alanine, respectively. The uncertainties in the experimental energy response estimates were typically 3%. The relative effectiveness, that is, the ratio of the experimental energy response to that following Monte Carlo simulations was, on average, 0.96 and 0.94 for lithium formate and alanine, respectively. Conclusions: This work shows that lithium formate dosimeters are less dependent on x-ray energy than alanine. Furthermore, as the relative effectiveness for both lithium formate and alanine were systematically less than unity, the yield of radiation-induced radicals is decreased following x-irradiation compared to irradiation with {sup 60}Co {gamma}-rays.

  17. MULTI-KEV X-RAY YIELDS FROM HIGH-Z GAS TARGETS FIELDED AT OMEGA

    SciTech Connect (OSTI)

    Kane, J O; Fournier, K B; May, M J; Colvin, J D; Thomas, C A; Marrs, R E; Compton, S M; Moody, J D; Bond, E J; Davis, J F

    2010-11-04

    The authors report on modeling of x-ray yield from gas-filled targets shot at the OMEGA laser facility. The OMEGA targets were 1.8 mm long, 1.95 mm in diameter Be cans filled with either a 50:50 Ar:Xe mixture, pure Ar, pure Kr or pure Xe at {approx} 1 atm. The OMEGA experiments heated the gas with 20 kJ of 3{omega} ({approx} 350 nm) laser energy delivered in a 1 ns square pulse. the emitted x-ray flux was monitored with the x-ray diode based DANTE instruments in the sub-keV range. Two-dimensional x-ray images (for energies 3-5 keV) of the targets were recorded with gated x-ray detectors. The x-ray spectra were recorded with the HENWAY crystal spectrometer at OMEGA. Predictions are 2D r-z cylindrical with DCA NLTE atomic physics. Models generally: (1) underpredict the Xe L-shell yields; (2) overpredict the Ar K-shell yields; (3) correctly predict the Xe thermal yields; and (4) greatly underpredict the Ar thermal yields. However, there are spreads within the data, e.g. the DMX Ar K-shell yields are correctly predicted. The predicted thermal yields show strong angular dependence.

  18. Template-based CTA to x-ray angio rigid registration of coronary arteries in frequency domain with automatic x-ray segmentation

    SciTech Connect (OSTI)

    Aksoy, Timur; Unal, Gozde; Demirci, Stefanie; Navab, Nassir; Degertekin, Muzaffer

    2013-10-15

    Purpose: A key challenge for image guided coronary interventions is accurate and absolutely robust image registration bringing together preinterventional information extracted from a three-dimensional (3D) patient scan and live interventional image information. In this paper, the authors present a novel scheme for 3D to two-dimensional (2D) rigid registration of coronary arteries extracted from preoperative image scan (3D) and a single segmented intraoperative x-ray angio frame in frequency and spatial domains for real-time angiography interventions by C-arm fluoroscopy.Methods: Most existing rigid registration approaches require a close initialization due to the abundance of local minima and high complexity of search algorithms. The authors' method eliminates this requirement by transforming the projections into translation-invariant Fourier domain for estimating the 3D pose. For 3D rotation recovery, template Digitally Reconstructed Radiographs (DRR) as candidate poses of 3D vessels of segmented computed tomography angiography are produced by rotating the camera (image intensifier) around the DICOM angle values with a specific range as in C-arm setup. The authors have compared the 3D poses of template DRRs with the segmented x-ray after equalizing the scales in three domains, namely, Fourier magnitude, Fourier phase, and Fourier polar. The best rotation pose candidate was chosen by one of the highest similarity measures returned by the methods in these domains. It has been noted in literature that frequency domain methods are robust against noise and occlusion which was also validated by the authors' results. 3D translation of the volume was then recovered by distance-map based BFGS optimization well suited to convex structure of the authors' objective function without local minima due to distance maps. A novel automatic x-ray vessel segmentation was also performed in this study.Results: Final results were evaluated in 2D projection space for patient data; and

  19. Real-time, high-resolution x-ray diffraction measurements on shocked crystals at a synchrotron facility

    SciTech Connect (OSTI)

    Gupta, Y. M.; Turneaure, Stefan J.; Perkins, K.; Zimmerman, K.; Arganbright, N.; Shen, G.; Chow, P.

    2012-12-15

    The Advanced Photon Source (APS) at Argonne National Laboratory was used to obtain real-time, high-resolution x-ray diffraction measurements to determine the microscopic response of shock-compressed single crystals. Disk shaped samples were subjected to plane shock wave compression by impacting them with half-inch diameter, flat-faced projectiles. The projectiles were accelerated to velocities ranging between 300 and 1200 m/s using a compact powder gun designed specifically for use at a synchrotron facility. The experiments were designed to keep the sample probed volume under uniaxial strain and constant stress for a duration longer than the 153.4 ns spacing between x-ray bunches. X-rays from a single pulse (<100 ps duration) out of the periodic x-ray pulses emitted by the synchrotron were used for the diffraction measurements. A synchronization and x-ray detection technique was developed to ensure that the measured signal was obtained unambiguously from the desired x-ray pulse incident on the sample while the sample was in a constant uniaxial strain state. The synchronization and x-ray detection techniques described can be used for a variety of x-ray measurements on shock compressed solids and liquids at the APS. Detailed procedures for applying the Bragg-Brentano parafocusing approach to single crystals at the APS are presented. Analytic developments to determine the effects of crystal substructure and non-ideal geometry on the diffraction pattern position and shape are presented. Representative real-time x-ray diffraction data, indicating shock-induced microstructural changes, are presented for a shock-compressed Al(111) sample. The experimental developments presented here provided, in part, the impetus for the Dynamic Compression Sector (DCS) currently under development at the APS. Both the synchronization/x-ray detection methods and the analysis equations for high-resolution single crystal x-ray diffraction can be used at the DCS.

  20. A laboratory-based hard x-ray monochromator for high-resolution x-ray emission spectroscopy and x-ray absorption near edge structure measurements

    SciTech Connect (OSTI)

    Seidler, G. T. Mortensen, D. R.; Remesnik, A. J.; Pacold, J. I.; Ball, N. A.; Barry, N.; Styczinski, M.; Hoidn, O. R.

    2014-11-15

    We report the development of a laboratory-based Rowland-circle monochromator that incorporates a low power x-ray (bremsstrahlung) tube source, a spherically bent crystal analyzer, and an energy-resolving solid-state detector. This relatively inexpensive, introductory level instrument achieves 1-eV energy resolution for photon energies of ∼5 keV to ∼10 keV while also demonstrating a net efficiency previously seen only in laboratory monochromators having much coarser energy resolution. Despite the use of only a compact, air-cooled 10 W x-ray tube, we find count rates for nonresonant x-ray emission spectroscopy comparable to those achieved at monochromatized spectroscopy beamlines at synchrotron light sources. For x-ray absorption near edge structure, the monochromatized flux is small (due to the use of a low-powered x-ray generator) but still useful for routine transmission-mode studies of concentrated samples. These results indicate that upgrading to a standard commercial high-power line-focused x-ray tube or rotating anode x-ray generator would result in monochromatized fluxes of order 10{sup 6}–10{sup 7} photons/s with no loss in energy resolution. This work establishes core technical capabilities for a rejuvenation of laboratory-based hard x-ray spectroscopies that could have special relevance for contemporary research on catalytic or electrical energy storage systems using transition-metal, lanthanide, or noble-metal active species.

  1. 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; Pacella, D.; Romano, A.; Gabellieri, L.; Kim, Junghee

    2014-11-15

    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 240 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.

  2. Feasibility of x ray fluorescence for spent fuel safeguards

    SciTech Connect (OSTI)

    Freeman, Corey Ross; Mozin, Vladimir; Tobin, Stephen J; Fensin, Michael L; White, Julia M; Croft, Stephen; Stafford, Alissa; Charlton, William

    2010-01-01

    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

  3. Continuous motion scan ptychography: Characterization for increased speed in coherent x-ray imaging

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

    Deng, Junjing; Nashed, Youssef S. G.; Chen, Si; Phillips, Nicholas W.; Peterka, Tom; Ross, Rob; Vogt, Stefan; Jacobsen, Chris; Vine, David J.

    2015-02-23

    Ptychography is a coherent diffraction imaging (CDI) method for extended objects in which diffraction patterns are acquired sequentially from overlapping coherent illumination spots. The objects complex transmission function can be reconstructed from those diffraction patterns at a spatial resolution limited only by the scattering strength of the object and the detector geometry. Most experiments to date have positioned the illumination spots on the sample using a move-settle-measure sequence in which the move and settle steps can take longer to complete than the measure step. We describe here the use of a continuous fly-scan mode for ptychographic data collection in whichmorethe sample is moved continuously, so that the experiment resembles one of integrating the diffraction patterns from multiple probe positions. This allows one to use multiple probe mode reconstruction methods to obtain an image of the object and also of the illumination function. We show in simulations, and in x-ray imaging experiments, some of the characteristics of fly-scan ptychography, including a factor of 25 reduction in the data acquisition time. This approach will become increasingly important as brighter x-ray sources are developed, such as diffraction limited storage rings.less

  4. Model independent x-ray standing wave analysis of periodic multilayer structures

    SciTech Connect (OSTI)

    Yakunin, S. N.; Pashaev, E. M.; Subbotin, I. A.; Makhotkin, I. A.; Kruijs, R. W. E. van de; Zoethout, E.; Chuev, M. A.; Louis, E.; Seregin, S. Yu.; Novikov, D. V.; Bijkerk, F.; Kovalchuk, M. V.

    2014-04-07

    We present a model independent approach for the analysis of X-ray fluorescence yield modulated by an X-ray standing wave (XSW), that allow a fast reconstruction of the atomic distribution function inside a sample without fitting procedure. The approach is based on the direct regularized solution of the system of linear equations that characterizes the fluorescence yield. The suggested technique was optimized for, but not limited to, the analysis of periodic layered structures where the XSW is formed under Bragg conditions. The developed approach was applied to the reconstruction of the atomic distribution function for LaN/BN multilayers with 50 periods of 43 Å thick layers. The object is especially difficult to analyze with traditional methods, as the estimated thickness of the interface region between the constituent materials is comparable to the individual layer thicknesses. However, using the suggested technique, it was possible to reconstruct width of the La atomic distribution showing that the La atoms stay localized within the LaN layers and interfaces and do not diffuse into the BN layer. The analysis of the reconstructed profiles showed that the positions of the center of the atomic distribution function can be estimated with an accuracy of 1 Å.

  5. Prospects for measuring neutron-star masses and radii with X-ray pulse profile modeling

    SciTech Connect (OSTI)

    Psaltis, Dimitrios; Özel, Feryal; Chakrabarty, Deepto E-mail: fozel@email.arizona.edu

    2014-06-01

    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 case for the forthcoming NICER and proposed LOFT X-ray missions. In this paper, we determine the number of distinct observables that can be derived from pulse profile modeling and show that using only bolometric pulse profiles is insufficient for breaking the degeneracy between inferred neutron-star radius and mass. However, we also show that for moderately spinning (300-800 Hz) neutron stars, analysis of pulse profiles in two different energy bands provides additional constraints that allow a unique determination of the neutron-star properties. Using the fractional amplitudes of the fundamental and the second harmonic of the pulse profile in addition to the amplitude and phase difference of the spectral color oscillations, we quantify the signal-to-noise ratio necessary to achieve a specified measurement precision for neutron star radius. We find that accumulating 10{sup 6} counts in a pulse profile is sufficient to achieve a ≲ 5% uncertainty in the neutron star radius, which is the level of accuracy required to determine the equation of state of neutron-star matter. Finally, we formally derive the background limits that can be tolerated in the measurements of the various pulsation amplitudes as a function of the system parameters.

  6. Diffuse X-ray emission from the superbubbles N70 and N185 in the Large Magellanic Cloud

    SciTech Connect (OSTI)

    Reyes-Iturbide, J.; Rodríguez-González, A.; Velázquez, P. F.; Rosado, M.; Sánchez-Cruces, M.; Ambrocio-Cruz, P.

    2014-11-01

    We present a study of the diffuse X-ray emission from superbubbles (SBs) N70 (DEM L301) and N185 (DEM L25) located in the Large Magellanic Cloud, based on data from the XMM-Newton Satellite. We obtained spectra and images of these objects in the soft X-ray energy band. These X-ray spectra were fitted by a thermal plasma model, with temperatures of 2.6×10{sup 6} K and 2.3×10{sup 6} K, for N70 and N185, respectively. For N70, images show that X-ray emission comes from the inner regions of the SB when we compare the distribution of the X-ray and the optical emission, while for N185, the X-ray emission is partially confined by the optical shell. We suggest that the observed X-ray emission is caused by shock-heated gas, inside of the optical shells. We also obtained X-ray luminosities which exceed the values predicted by the standard analytical model. This fact shows that, in addition to the winds of the interior stars, it is necessary to consider another ingredient in the description, such as a supernova explosion, as has been proposed in previous numerical models.

  7. Gated monochromatic x-ray imager

    SciTech Connect (OSTI)

    Oertel, J.A.; Archuleta, T.; Clark, L.

    1995-09-01

    We have recently developed a gated monochromatic x-ray imaging diagnostic for the national Inertial-Confinement Fusion (ICF) program. This new imaging system will be one of the primary diagnostics to be utilized on University of Rochester`s Omega laser fusion facility. The new diagnostic is based upon a Kirkpatrick-Baez (KB) microscope dispersed by diffraction crystals, as first described by Marshall and Su. The dispersed images are gated by four individual proximity focused microchannel plates and recorded on film. Spectral coverage is tunable up to 8 keV, spectral resolution has been measured at 20 eV, temporal resolution is 80 ps, and spatial resolution is better than 10 {mu}m.

  8. Image segmentation of nanoscale Zernike phase contrast X-ray computed tomography images

    SciTech Connect (OSTI)

    Kumar, Arjun S.; Mandal, Pratiti; Zhang, Yongjie; Litster, Shawn

    2015-05-14

    Zernike phase contrast is a useful technique for nanoscale X-ray computed tomography (CT) imaging of materials with a low X-ray absorption coefficient. It enhances the image contrast by phase shifting X-ray waves to create changes in amplitude. However, it creates artifacts that hinder the use of traditional image segmentation techniques. We propose an image restoration method that models the X-ray phase contrast optics and the three-dimensional image reconstruction method. We generate artifact-free images through an optimization problem that inverts this model. Though similar approaches have been used for Zernike phase contrast in visible light microscopy, this optimization employs an effective edge detection method tailored to handle Zernike phase contrast artifacts. We characterize this optics-based restoration method by removing the artifacts in and thresholding multiple Zernike phase contrast X-ray CT images to produce segmented results that are consistent with the physical specimens. We quantitatively evaluate and compare our method to other segmentation techniques to demonstrate its high accuracy.

  9. X-ray emission from a nanosecond-pulse discharge in an inhomogeneous electric field at atmospheric pressure

    SciTech Connect (OSTI)

    Zhang Cheng; Shao Tao; Ren Chengyan; Zhang Dongdong; Tarasenko, Victor; Kostyrya, Igor D.; Ma Hao; Yan Ping

    2012-12-15

    This paper describes experimental studies of the dependence of the X-ray intensity on the anode material in nanosecond high-voltage discharges. The discharges were generated by two nanosecond-pulse generators in atmospheric air with a highly inhomogeneous electric field by a tube-plate gap. The output pulse of the first generator (repetitive pulse generator) has a rise time of about 15 ns and a full width at half maximum of 30-40 ns. The output of the second generator (single pulse generator) has a rise time of about 0.3 ns and a full width at half maximum of 1 ns. The electrical characteristics and the X-ray emission of nanosecond-pulse discharge in atmospheric air are studied by the measurement of voltage-current waveforms, discharge images, X-ray count and dose. Our experimental results showed that the anode material rarely affects electrical characteristics, but it can significantly affect the X-ray density. Comparing the density of X-rays, it was shown that the highest x-rays density occurred in the diffuse discharge in repetitive pulse mode, then the spark discharge with a small air gap, and then the corona discharge with a large air gap, in which the X-ray density was the lowest. Therefore, it could be confirmed that the bremsstrahlung at the anode contributes to the X-ray emission from nanosecond-pulse discharges.

  10. Fabrication process for a gradient index x-ray lens

    DOE Patents [OSTI]

    Bionta, R.M.; Makowiecki, D.M.; Skulina, K.M.

    1995-01-17

    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.

  11. Fabrication process for a gradient index x-ray lens

    DOE Patents [OSTI]

    Bionta, Richard M.; Makowiecki, Daniel M.; Skulina, Kenneth M.

    1995-01-01

    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.

  12. Density gradient free electron collisionally excited x-ray laser

    DOE Patents [OSTI]

    Campbell, E.M.; Rosen, M.D.

    1984-11-29

    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.

  13. Soft x-ray reduction camera for submicron lithography

    DOE Patents [OSTI]

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

    1991-03-26

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

  14. Soft x-ray reduction camera for submicron lithography

    DOE Patents [OSTI]

    Hawryluk, Andrew M.; Seppala, Lynn G.

    1991-01-01

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

  15. Density gradient free electron collisionally excited X-ray laser

    DOE Patents [OSTI]

    Campbell, Edward M.; Rosen, Mordecai D.

    1989-01-01

    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.

  16. The Application of Monochromatic Energies to Investigate Multiphase Porous Media Systems using Synchrotron X-ray Tomography

    SciTech Connect (OSTI)

    Ham, Kyungmin; Willson, Clinton S.

    2006-01-31

    X-ray computed tomography (CT) is becoming a useful tool for nondestructive imaging of many geoenvironmental and geotechnical systems. Conventional X-ray CT systems typically utilize a polychromatic X-ray beam. While providing a high throughput of photons, the use of polychromatic energy can make quantifying material concentrations, densities or composition very difficult or impossible without appropriate standards. Synchrotron X-rays have an extremely small angular divergence, thus permitting spatial resolution that is only limited by the optical components of the system. In addition, the ability to tune to a monochromatic X-ray energy allows better phase contrast by reducing beam hardening and allowing for elemental discrimination. In this work we will show how monochromatic energy can be used to provide high-quality images allowing for phase separation several different porous media systems thus improving our ability to quantify a range of processes and phenomena.

  17. Wide band focusing x-ray spectrograph with spatial resolution

    SciTech Connect (OSTI)

    Pikuz, S. A.; Douglass, J. D.; Shelkovenko, T. A.; Sinars, D. B.; Hammer, D. A.

    2008-01-15

    A new, wide spectral bandwidth x-ray spectrograph, the wide-bandwidth focusing spectrograph with spatial resolution (WB-FSSR), based on spherically bent mica crystals, is described. The wide bandwidth is achieved by combining three crystals to form a large aperture dispersive element. Since the WB-FSSR covers a wide spectral band, it is very convenient for application as a routine diagnostic tool in experiments in which the desired spectral coverage is different from one test to the next. The WB-FSSR has been tested in imploding wire-array experiments on a 1 MA pulsed power machine, and x-ray spectra were recorded in the 1-20 A spectral band using different orders of mica crystal reflection. Using a two mirror-symmetrically placed WB-FSSR configuration, it was also possible to distinguish between a real spectral shift and a shift of recorded spectral lines caused by the spatial distribution of the radiating plasma. A spectral resolution of about 2000 was demonstrated and a spatial resolution of {approx}100 {mu}m was achieved in the spectral band of 5-10 A in second order of mica reflection. A simple method of numerical analysis of spectrograph capability is proposed.

  18. Selenium Preferentially Accumulates in the Eye Lens Following Embryonic Exposure: A Confocal X-ray Fluorescence Imaging Study

    SciTech Connect (OSTI)

    Choudhury, Sanjukta; Thomas, Jith; Sylvain, Nicole J.; Ponomarenko, Olena; Gordon, Robert A.; Heald, Steve M.; Janz, David M.; Krone, Patrick H.; Coulthard, Ian; George, Graham N.; Pickering, Ingrid J.

    2015-02-17

    Maternal transfer of elevated selenium (Se) to offspring is an important route of Se exposure for fish in the natural environment. However, there is a lack of information on the tissue specific spatial distribution and speciation of Se in the early developmental stages of fish, which provide important information about Se toxicokinetics. The effect of maternal transfer of Se was studied by feeding adult zebrafish a Se-elevated or a control diet followed by collection of larvae from both groups. Novel confocal synchrotron-based techniques were used to investigate Se within intact preserved larvae. Confocal X-ray fluorescence imaging was used to compare Se distributions within specific planes of an intact larva from each of the two groups. The elevated Se treatment showed substantially higher Se levels than the control; Se preferentially accumulated to highest levels in the eye lens, with lower levels in the retina, yolk and other tissues. Confocal X-ray absorption spectroscopy was used to determine that the speciation of Se within the eye lens of the intact larva was a selenomethionine-like species. Preferential accumulation of Se in the eye lens may suggest a direct cause-and-effect relationship between exposure to elevated Se and Se-induced ocular impairments reported previously. This study illustrates the effectiveness of confocal X-ray fluorescence methods for investigating trace element distribution and speciation in intact biological specimens

  19. Quality indexes based on water measurements for low and medium energy x-ray beams: A theoretical study with PENELOPE

    SciTech Connect (OSTI)

    Chica, U.; Anguiano, M.; Lallena, A. M.; Vilches, M.

    2014-01-15

    Purpose : To study the use of quality indexes based on ratios of absorbed doses in water at two different depths to characterize x-ray beams of low and medium energies. Methods : A total of 55 x-ray beam spectra were generated with the codes XCOMP5R and SPEKCALC and used as input of a series of Monte Carlo simulations performed with PENELOPE, in which the percentage depth doses in water and thek{sub Q,Q{sub 0}} factors, defined in the TRS-398 protocol, were determined for each beam. Some of these calculations were performed by simulating the ionization chamber PTW 30010. Results : The authors found that the relation betweenk{sub Q,Q{sub 0}} and the ratios of absorbed doses at two depths is almost linear. A set of ratios statistically compatible with that showing the best fit has been determined. Conclusions : The results of this study point out which of these ratios of absorbed doses in water could be used to better characterize x-ray beams of low and medium energies.

  20. Ligand-field symmetry effects in Fe(II) polypyridyl compounds probed by transient X-ray absorption spectroscopy

    SciTech Connect (OSTI)

    Cho, Hana; Strader, Matthew L.; Hong, Kiryong; Jamula, Lindsey; Kim, Tae Kyu; Groot, Frank M. F. de; McCusker, James K.; Schoenlein, Robert W.; Huse, Nils

    2012-02-28

    Ultrafast excited-state evolution in polypyridyl FeII complexes are of fundamental interest for understanding the origins of the sub-ps spin-state changes that occur upon photoexcitation of this class of compounds as well as for the potential impact such ultrafast dynamics have on incorporation of these compounds in solar energy conversion schemes or switchable optical storage technologies. We have demonstrated that ground-state and, more importantly, ultrafast time-resolved x-ray absorption methods can offer unique insights into the interplay between electronic and geometric structure that underpin the photo-induced dynamics of this class of compounds. The present contribution examines in greater detail how the symmetry of the ligand field surrounding the metal ion can be probed using these x-ray techniques. In particular, we show that steady-state K-edge spectroscopy of the nearest-neighbour nitrogen atoms reveals the characteristic chemical environment of the respective ligands and suggests an interesting target for future charge-transfer femtosecond and attosecond spectroscopy in the x-ray water window.

  1. Femtosecond nanocrystallography using X-ray lasers for membrane protein

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

    structure determination Femtosecond nanocrystallography using X-ray lasers for membrane protein structure determination Authors: Fromme, P., and Spence, J. C. H. Title: Femtosecond nanocrystallography using X-ray lasers for membrane protein structure determination Source: Current Opinion in Structural Biology Year: 2011 Volume: 21 Pages: 509-516 ABSTRACT: The invention of free electron X-ray lasers has opened a new era for membrane protein structure determination with the recent first

  2. ANL CT Reconstruction Algorithm for Utilizing Digital X-ray

    Energy Science and Technology Software Center (OSTI)

    2004-05-01

    Reconstructs X-ray computed tomographic images from large data sets known as 16-bit binary sinograms when using a massively parallelized computer architecture such as a Beowuif cluster by parallelizing the X-ray CT reconstruction routine. The algorithm uses the concept of generation of an image from carefully obtained multiple 1-D or 2-D X-ray projections. The individual projections are filtered using a digital Fast Fourier Transform. The literature refers to this as filtered back projection.

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

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

    Unexpected Angular Dependence of X-Ray Magnetic Linear Dichroism Unexpected Angular Dependence of X-Ray Magnetic Linear Dichroism Print Wednesday, 29 August 2007 00:00 Using spectroscopic information for magnetometry and magnetic microscopy obviously requires detailed theoretical understanding of spectral shape and magnitude of dichroism signals. A research team at ALS Beamline 4.0.2 has now shown unambiguously that, contrary to common belief, spectral shape and magnitude of x-ray magnetic

  4. Legacy of the X-Ray Laser Program

    SciTech Connect (OSTI)

    Nilsen, J.

    1993-08-06

    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.

  5. Magnetism studies using resonant, coherent, x-ray scattering | Stanford

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

    Synchrotron Radiation Lightsource 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 lasers there has been interest in using coherent x-rays to probe condensed matter systems. Resonant scattering with x-rays allow elemental specificity with magnetic contrast, and coherent light leads to speckle in the scattered pattern due to interference from waves exiting the sample.

  6. X-ray interferometry with spherically bent crystals (abstract)

    SciTech Connect (OSTI)

    Koch, Jeffrey A.

    2001-01-01

    Recent progress in manufacturing high-quality spherically bent crystals allows highly monochromatic x-ray beams to be produced, and allows efficient x-ray imaging with {mu}m-scale resolution. This article explores some of the constraints for x-ray interferometry utilizing spherically bent crystals and laser-produced plasma sources, and discusses several shearing interferometer concepts that might be experimentally investigated.

  7. Bimolecular Imaging with femtosecond X-ray pulses | Stanford Synchrotron

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

    Radiation Lightsource Bimolecular Imaging with femtosecond X-ray pulses Wednesday, June 22, 2016 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Speaker: Marvin Seibert, Uppsala University Program Description This talk will be part review, part outlook of the potential for imaging biological structures with fs X-ray pulses, from the first experiments at LCLS to the current single particle imaging initiative. Bimolecular Imaging with femtosecond X-ray pulses

  8. Characterization of the Electronic Structure of Silicon Nanoparticles Using X-ray Absorption and Emission

    SciTech Connect (OSTI)

    Vaverka, A M

    2008-07-15

    Resolving open questions regarding transport in nanostructures can have a huge impact on a broad range of future technologies such as light harvesting for energy. Silicon has potential to be used in many of these applications. Understanding how the band edges of nanostructures move as a function of size, surface termination and assembly is of fundamental importance in understanding the transport properties of these materials. In this thesis work I have investigated the change in the electronic structure of silicon nanoparticle assemblies as the surface termination is changed. Nanoparticles are synthesized using a thermal evaporation technique and sizes are determined using atomic force microscopy (AFM). By passivating the particles with molecules containing alcohol groups we are able to modify the size dependent band edge shifts. Both the valence and conduction bands are measured using synchrotron based x-ray absorption spectroscopy (XAS) and soft x-ray fluorescence (SXF) techniques. Particles synthesized via recrystallization of amorphous silicon/SiO{sub 2} multilayers of thicknesses below 10 nm are also investigated using the synchrotron techniques. These samples also show quantum confinement effects but the electronic structure is different from those synthesized via evaporation methods. The total bandgap is determined for all samples measured. The origins of these differences in the electronic structures are discussed.

  9. DISTRIBUTION OF HIGH-MASS X-RAY BINARIES IN THE MILKY WAY

    SciTech Connect (OSTI)

    Coleiro, Alexis; Chaty, Sylvain E-mail: chaty@cea.fr

    2013-02-20

    Observations of the high-energy sky, particularly with the INTEGRAL satellite, have quadrupled the number of supergiant X-ray binaries observed in the Galaxy and revealed new populations of previously hidden high-mass X-ray binaries (HMXBs), raising new questions about their formation and evolution. The number of detected HMXBs of different types is now high enough to allow us to carry out a statistical analysis of their distribution in the Milky Way. For the first time, we derive the distance and absorption of a sample of HMXBs using a spectral energy distribution fitting procedure, and we examine the correlation with the distribution of star-forming complexes (SFCs) in the Galaxy. We show that HMXBs are clustered with SFCs with a typical cluster size of 0.3 {+-} 0.05 kpc and a characteristic distance between clusters of 1.7 {+-} 0.3 kpc. Furthermore, we present an investigation of the expected offset between the position of spiral arms and HMXBs, allowing us to constrain age and migration distance due to supernova kick for 13 sources. These new methods will allow us to assess the influence of the environment on these high-energy objects with unprecedented reliability.

  10. X-Ray Fluorescence (XRF) | Open Energy Information

    Open Energy Info (EERE)

    Dispersive Spectroscopy (WDS) typically performed using a SEM or EPMA, and X-Ray Diffraction (XRD) analyses. Rock Lab Analysis Core Analysis Cuttings Analysis Isotopic...

  11. XRMS: X-Ray Spectroscopy of Magnetic Solids

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

    XRMS: X-Ray Spectroscopy of Magnetic Solids October 22-23, 2011 SLAC National Accelerator Laboratory, Menlo Park, CA More information...

  12. High intensity x-ray source using liquid gallium target

    DOE Patents [OSTI]

    Smither, Robert K.; Knapp, Gordon S.; Westbrook, Edwin M.; Forster, George A.

    1990-01-01

    A high intensity x-ray source that uses a flowing stream of liquid gallium as a target with the electron beam impinging directly on the liquid metal.

  13. ALS X-Rays Shine a New Light on Catalysis

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

    ALS X-Rays Shine a New Light on Catalysis Print Electrocatalysts are responsible for expediting reactions in many promising renewable energy technologies. However, the extreme...

  14. Subject: Ames Blue Alert - X-ray Shutter Maintenance

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

    Ames Blue Alert - X-ray Shutter Maintenance Statement: This lesson learned involves an ... 4. Follow the manufacturers suggested maintenance schedule. 5. Follow the standard ...

  15. X-Ray Microscopy Capabilities | Argonne National Laboratory

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

    X-Ray Microscopy Capabilities The Hard X-Ray Nanoprobe (HXN) facility provides scanning fluorescence, scanning diffraction, and full-field transmission and tomographic imaging capabilities with a spatial resolution of 30 nm over a spectral range of 6-12 keV. Modes of Operation Full-Field Transmission Imaging and Nanotomography X-ray transmission imaging uses both the absorption and phase shift of the X-ray beam by the sample as contrast mechanisms. Absorption contrast is used to map the sample

  16. Simulating Wavefront Correction via Deformable Mirrors at X-Ray...

    Office of Scientific and Technical Information (OSTI)

    Conference: Simulating Wavefront Correction via Deformable Mirrors at X-Ray Beamlines Citation Details In-Document Search Title: Simulating Wavefront Correction via Deformable ...

  17. In Situ Ambient Pressure X-ray Photoelectron Spectroscopy Studies...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: In Situ Ambient Pressure X-ray ... Citation Details In-Document Search Title: In Situ Ambient ... Resource Relation: Journal Name: Scientific Reports; Journal ...

  18. Absolute Time-Resolved X-Ray Laser Gain Measurement

    SciTech Connect (OSTI)

    Mocek, T.; Sebban, S.; Zeitoun, Ph.; Faivre, G.; Hallou, A.; Rousseau, J.P.; Maynard, G.; Cros, B.; Fajardo, M.; Kazamias, S.; Dubau, J.; Aubert, D.; Lacheze-Murel, G. de

    2005-10-21

    We present the first direct measurement of the time evolution of the gain of a soft x-ray laser amplifier. The measurement is based on the injection of a seed pulse, obtained by high-order harmonic generation, into an x-ray laser medium. Strong amplification occurs when the seed pulse is synchronized with the gain period. By precisely varying the delay between the x-ray laser plasma creation and the seed pulse injection, the actual temporal evolution of the soft x-ray amplifier gain is obtained with a subpicosecond resolution.

  19. Biological Imaging by Soft X-Ray Diffraction Microscopy

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

    Biological Imaging by Soft X-Ray Diffraction Microscopy Biological Imaging by Soft X-Ray Diffraction Microscopy Print Wednesday, 30 November 2005 00:00 Electron and x-ray microscopes are a valuable tool for both the life and materials sciences, but they are limited in their ability to image with nanometer-scale resolution in three dimensions nonperiodic objects that are several microns in size. To fill this gap, the technique of coherent x-ray diffraction imaging now under development takes

  20. Diagnostics Implemented on NIF - X-ray Diagnostics

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

    X-ray Diagnostics Diagnostic acronym Diangostic Port location Built and commisioned by Description of function Published references ARIANE Active Readout in a Neutron Environment (gated x-ray imager) 90-89 (but uses DIM) LLNL ARIANE is a gated x-ray detector measuring x-ray output at yields up to ~1E16 neutrons from TCC. ARIANE uses gated MCP technology adapted to operate in this neutron regime by moving the detector to a position just outside of the target chamber wall. ARIANE is typically used

  1. X-ray image reconstruction from a diffraction pattern alone

    SciTech Connect (OSTI)

    Marchesini, Stefano

    2015-03-16

    X-ray diffraction pattern of a sample of 50 nm colloidal gold particles, recorded at a wavelength of 2.1 nm.

  2. Normal incidence x-ray mirror for chemical microanalysis

    DOE Patents [OSTI]

    Carr, M.J.; Romig, A.D. Jr.

    1987-08-05

    An x-ray mirror for both electron column instruments and micro x-ray fluorescence instruments for making chemical, microanalysis comprises a non-planar mirror having, for example, a spherical reflecting surface for x-rays comprised of a predetermined number of alternating layers of high atomic number material and low atomic number material contiguously formed on a substrate and whose layers have a thickness which is a multiple of the wavelength being reflected. For electron column instruments, the wavelengths of interest lie above 1.5nm, while for x-ray fluorescence instruments, the range of interest is below 0.2nm. 4 figs.

  3. X-ray crystallographic analysis of adipocyte fatty acid binding...

    Office of Scientific and Technical Information (OSTI)

    X-ray crystallographic analysis of adipocyte fatty acid binding protein (aP2) modified ... LIFE SCIENCES; ALDEHYDES; CARBOXYLIC ACIDS; CRYSTAL STRUCTURE; IN VIVO; INFLAMMATION; ...

  4. Staff Research Physicist (X-Ray Spectroscopy) | Princeton Plasma...

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

    of X-ray spectrometers for high energy density plasma at the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory (LLNL, Livermore, California). In...

  5. X-Ray Microscopy Reveals How Crystal Mechanics Drive Battery...

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

    X-Ray Microscopy Reveals How Crystal Mechanics Drive Battery Performance Print ... are one of the best performing battery electrode materials, able to repeatedly ...

  6. Portable X-Ray Diffraction (XRD) | Open Energy Information

    Open Energy Info (EERE)

    X-ray powder diffraction, which has traditionally been used in geology, environmental science, material science, and engineering to rapidly identify unknown crystalline...

  7. X-Ray Diffraction (XRD) | Open Energy Information

    Open Energy Info (EERE)

    under investigation. X-ray powder diffraction is widely used in geology, environmental science, material science, and engineering to rapidly identify unknown crystalline substances...

  8. X-Ray Characterization of Diesel Sprays | Department of Energy

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

    Sprays X-Ray Characterization of Diesel Sprays 2005 Diesel Engine Emissions Reduction (DEER) Conference Presentations and Posters 2005deerpowell.pdf (1.19 MB) More Documents & ...

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

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

    Unexpected Angular Dependence of X-Ray Magnetic Linear Dichroism Print Using spectroscopic ... The effect is unique in that it allows us to distinguish which atomic species magnetism ...

  10. Advances in X-Ray Diagnostics of Diesel Fuel Sprays

    Broader source: Energy.gov [DOE]

    Recent advances in high-speed X-ray imaging has shown several distinct behaviors of commercial fuel injectors that cannot be seen with more conventional techniques.

  11. ALS X-Rays Shine a New Light on Catalysis

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

    were able to directly observe redox processes in thin-film iron and cobalt perovskite oxide electrocatalysts using surface-sensitive, x-ray absorption spectroscopy while...

  12. X-Ray Diffraction Microscopy of Magnetic Structures (Journal...

    Office of Scientific and Technical Information (OSTI)

    Prev Next Title: X-Ray Diffraction Microscopy of Magnetic Structures Authors: Turner, Joshua J. ; Huang, Xiaojing ; Krupin, Oleg ; Seu, Keoki A. ; Parks, Daniel ; Kevan,...

  13. Stimulated X-Ray Emission for Spectroscopy | Stanford Synchrotron...

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

    Room 108A Speaker: Clemens Weninger, Max Planck Institute for the Physics of Complex Systems Program Description The recent advance of x-ray free electron lasers (XFELs)...

  14. X-ray Moiré deflectometry using synthetic reference images

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

    Stutman, Dan; Valdivia, Maria Pia; Finkenthal, Michael

    2015-06-25

    Moiré fringe deflectometry with grating interferometers is a technique that enables refraction-based x-ray imaging using a single exposure of an object. To obtain the refraction image, the method requires a reference fringe pattern (without the object). Our study shows that, in order to avoid artifacts, the reference pattern must be exactly matched in phase with the object fringe pattern. In experiments, however, it is difficult to produce a perfectly matched reference pattern due to unavoidable interferometer drifts. We present a simple method to obtain matched reference patterns using a phase-scan procedure to generate synthetic Moiré images. As a result, themore » method will enable deflectometric diagnostics of transient phenomena such as laser-produced plasmas and could improve the sensitivity and accuracy of medical phase-contrast imaging.« less

  15. X-ray Moiré deflectometry using synthetic reference images

    SciTech Connect (OSTI)

    Stutman, Dan; Valdivia, Maria Pia; Finkenthal, Michael

    2015-06-25

    Moiré fringe deflectometry with grating interferometers is a technique that enables refraction-based x-ray imaging using a single exposure of an object. To obtain the refraction image, the method requires a reference fringe pattern (without the object). Our study shows that, in order to avoid artifacts, the reference pattern must be exactly matched in phase with the object fringe pattern. In experiments, however, it is difficult to produce a perfectly matched reference pattern due to unavoidable interferometer drifts. We present a simple method to obtain matched reference patterns using a phase-scan procedure to generate synthetic Moiré images. As a result, the method will enable deflectometric diagnostics of transient phenomena such as laser-produced plasmas and could improve the sensitivity and accuracy of medical phase-contrast imaging.

  16. Two-Bunch Self-Seeding for Narrow-Bandwidth Hard X-Ray Free-Electron...

    Office of Scientific and Technical Information (OSTI)

    one of the most promising methods to accomplish this. In the hard x-ray regime with high- energy electrons, this method requires a large magnetic chicane to match the path length...

  17. Learning to Apply Metrology Principles to the Measurement of X-ray Intensities in the 500 eV to 110 keV Energy Range

    SciTech Connect (OSTI)

    Haugh, M. J.; Pond, T.; Silbernagel, C.; Torres, P.; Marlett, K.; Goldin, F.; Cyr, S.

    2011-02-08

    National Security Technologies, LLC (NSTec), Livermore Operations, has two optical radiation calibration laboratories accredited by “the National Voluntary Laboratories Accreditation Program (NVLAP) which is the accrediting body of” the National Institute of Standards and Technology (NIST), and is now working towards accreditation for its X-ray laboratories. NSTec operates several laboratories with X-ray sources that generate X-rays in the energy range from 50 eV to 115 keV. These X-ray sources are used to characterize and calibrate diagnostics and diagnostic components used by the various national laboratories, particularly for plasma analysis on the Lawrence Livermore National Laboratory (LLNL) National Ignition Facility (NIF). Because X-ray photon flux measurement methods that can be accredited, i.e., traceable to NIST, have not been developed for sources operating in these energy ranges, NSTec, NIST, and the National Voluntary Accreditation Program (NVLAP) together have defined a path toward the development and validation of accredited metrology methods for X-ray energies. The methodology developed for the high energy X-ray (HEX) Laboratory was NSTec’s starting point for X-ray metrology accreditation and will be the basis for the accredited processes in the other X-ray laboratories. This paper will serve as a teaching tool, by way of this example using the NSTec X-ray sources, for the process and methods used in developing an accredited traceable metrology.

  18. 3D localization of electrophysiology catheters from a single x-ray cone-beam projection

    SciTech Connect (OSTI)

    Robert, Normand Polack, George G.; Sethi, Benu; Rowlands, John A.; Crystal, Eugene

    2015-10-15

    Purpose: X-ray images allow the visualization of percutaneous devices such as catheters in real time but inherently lack depth information. The provision of 3D localization of these devices from cone beam x-ray projections would be advantageous for interventions such as electrophysiology (EP), whereby the operator needs to return a device to the same anatomical locations during the procedure. A method to achieve real-time 3D single view localization (SVL) of an object of known geometry from a single x-ray image is presented. SVL exploits the change in the magnification of an object as its distance from the x-ray source is varied. The x-ray projection of an object of interest is compared to a synthetic x-ray projection of a model of said object as its pose is varied. Methods: SVL was tested with a 3 mm spherical marker and an electrophysiology catheter. The effect of x-ray acquisition parameters on SVL was investigated. An independent reference localization method was developed to compare results when imaging a catheter translated via a computer controlled three-axes stage. SVL was also performed on clinical fluoroscopy image sequences. A commercial navigation system was used in some clinical image sequences for comparison. Results: SVL estimates exhibited little change as x-ray acquisition parameters were varied. The reproducibility of catheter position estimates in phantoms denoted by the standard deviations, (σ{sub x}, σ{sub y}, σ{sub z}) = (0.099 mm,  0.093 mm,  2.2 mm), where x and y are parallel to the detector plane and z is the distance from the x-ray source. Position estimates (x, y, z) exhibited a 4% systematic error (underestimation) when compared to the reference method. The authors demonstrated that EP catheters can be tracked in clinical fluoroscopic images. Conclusions: It has been shown that EP catheters can be localized in real time in phantoms and clinical images at fluoroscopic exposure rates. Further work is required to characterize

  19. High-Resolution Structure of the Photosynthetic Mn4Ca Catalyst from X-ray Spectroscopy

    SciTech Connect (OSTI)

    Yachandra, Vittal; Yano, Junko; Kern, Jan; Pushkar, Yulia; Sauer, Kenneth; Glatzel, Pieter; Bergmann, Uwe; Messinger, Johannes; Zouni, Athina; Yachandra, Vittal K.

    2007-08-01

    The application of high-resolution X-ray spectroscopy methods to study the photosynthetic water oxidizing complex, which contains a unique hetero-nuclear catalytic Mn4Ca cluster, are described. Issues of X-ray damage especially at the metal sites in the Mn4Ca cluster are discussed. The structure of the Mn4Ca catalyst at high-resolution which has so far eluded attempts of determination by X-ray diffraction, EXAFS and other spectroscopic techniques has been addressed using polarized EXAFS techniques applied to oriented PS II membrane preparations and PS II single crystals. A review of how the resolution of traditional EXAFS techniques can be improved, using methods such as range-extended EXAFS is presented, and the changes that occur in the structure of the cluster as it advances through the catalytic cycle are described. X-ray absorption and emission techniques (XANES and K? emission) have been used earlier to determine the oxidation states of the Mn4Ca cluster, and in this report we review the use of X-ray resonant Raman spectroscopy to understand the electronic structure of the Mn4Ca cluster as it cycles through the intermediate S-states.

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

    SciTech Connect (OSTI)

    Greaves, E. D.; Barros, H.; Bermudez, J.; Sajo-Bohus, L.; Angeli-Greaves, M.

    2007-10-26

    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.

  1. A paediatric X-ray exposure chart

    SciTech Connect (OSTI)

    Knight, Stephen P

    2014-09-15

    The aim of this review was to develop a radiographic optimisation strategy to make use of digital radiography (DR) and needle phosphor computerised radiography (CR) detectors, in order to lower radiation dose and improve image quality for paediatrics. This review was based on evidence-based practice, of which a component was a review of the relevant literature. The resulting exposure chart was developed with two distinct groups of exposure optimisation strategies – body exposures (for head, trunk, humerus, femur) and distal extremity exposures (elbow to finger, knee to toe). Exposure variables manipulated included kilovoltage peak (kVp), target detector exposure and milli-ampere-seconds (mAs), automatic exposure control (AEC), additional beam filtration, and use of antiscatter grid. Mean dose area product (DAP) reductions of up to 83% for anterior–posterior (AP)/posterior–anterior (PA) abdomen projections were recorded postoptimisation due to manipulation of multiple-exposure variables. For body exposures, the target EI and detector exposure, and thus the required mAs were typically 20% less postoptimisation. Image quality for some distal extremity exposures was improved by lowering kVp and increasing mAs around constant entrance skin dose. It is recommended that purchasing digital X-ray equipment with high detective quantum efficiency detectors, and then optimising the exposure chart for use with these detectors is of high importance for sites performing paediatric imaging. Multiple-exposure variables may need to be manipulated to achieve optimal outcomes.

  2. X-ray K-edge analysis of drain lines in Wilhelm Hall, Ames Laboratory

    SciTech Connect (OSTI)

    Jensen, T.; Whitmore, C. |

    1999-01-05

    From August 12--27, 1998 X-ray K-edge measurements were made on drain lines in seven rooms in Wilhelm Hall, Ames Laboratory. The purpose of these measurements was to determine the extent of thorium (and other heavy metal) contamination inside these pipes. The K-edge method is a noninvasive inspection technique that can provide accurate quantification of heavy metal contamination interior to an object. Of the seven drain lines inspected, one was found to have no significant contamination, three showed significant thorium deposits, two showed mercury contamination, and one line was found to contain mercury, thorium and uranium. The K-edge measurements were found to be consistent with readings from hand-held survey meters, and provided much greater detail on the location and amount of heavy metal contamination.

  3. A rapid noninvasive characterization of CT x-ray sources

    SciTech Connect (OSTI)

    Randazzo, Matt; Tambasco, Mauro

    2015-07-15

    Purpose: The aim of this study is to generate spatially varying half value layers (HVLs) that can be used to construct virtual equivalent source models of computed tomography (CT) x-ray sources for use in Monte Carlo CT dose computations. Methods: To measure the spatially varying HVLs, the authors combined a cylindrical HVL measurement technique with the characterization of bowtie filter relative attenuation (COBRA) geometry. An apparatus given the name “HVL Jig” was fabricated to accurately position a real-time dosimeter off-isocenter while surrounded by concentric cylindrical aluminum filters (CAFs). In this geometry, each projection of the rotating x-ray tube is filtered by an identical amount of high-purity (type 1100 H-14) aluminum while the stationary radiation dose probe records an air kerma rate versus time waveform. The CAFs were progressively nested to acquire exposure data at increasing filtrations to calculate the HVL. Using this dose waveform and known setup geometry, each timestamp was related to its corresponding fan angle. Data were acquired using axial CT protocols (i.e., rotating tube and stationary patient table) at energies of 80, 100, and 120 kVp on a single CT scanner. These measurements were validated against the more laborious conventional step-and-shoot approach (stationary x-ray tube). Results: At each energy, HVL data points from the COBRA-cylinder technique were fit to a trendline and compared with the conventional approach. The average relative difference in HVL between the two techniques was 1.3%. There was a systematic overestimation in HVL due to scatter contamination. Conclusions: The described method is a novel, rapid, accurate, and noninvasive approach that allows one to acquire the spatially varying fluence and HVL data using a single experimental setup in a minimum of three scans. These measurements can be used to characterize the CT beam in terms of the angle-dependent fluence and energy spectra along the bowtie filter

  4. Beam Physics in X-Ray Radiography Facilities

    SciTech Connect (OSTI)

    Chen, Y J; Caporaso, G J; Chambers, F W; Falabella, S; Goldin, F J; Guethlein, G; Lauer, E L; McCarrick, J F; Neurath, R; Richardson, R A; Sampayan, S; Weir, J T

    2002-12-02

    Performance of x-ray radiography facilities requires focusing the electron beams to sub-millimeter spots on the x-ray converters. Ions extracted from a converter by impact of a high intensity beam can partially neutralize the beam space charge and change the final focusing system. We will discuss these ion effects and mitigation.

  5. A metallography and x-ray tomography study of spall damage in ultrapure Al

    SciTech Connect (OSTI)

    Qi, M. L.; Bie, B. X.; Zhao, F. P.; Fan, D.; Luo, S. N.; Hu, C. M.; Ran, X. X.; Xiao, X. H.; Yang, W. G.; Li, P.

    2014-07-15

    We characterize spall damage in shock-recovered ultrapure Al with metallography and x-ray tomography. The measured damage profiles in ultrapure Al induced by planar impact at different shock strengths, can be described with a Gaussian function, and showed dependence on shock strengths. Optical metallography is reasonably accurate for damage profile measurements, and agrees within 10–25% with x-ray tomography. Full tomography analysis showed that void size distributions followed a power law with an exponent of γ = 1.5 ± 2.0, which is likely due to void nucleation and growth, and the exponent is considerably smaller than the predictions from percolation models.

  6. X-ray power and yield measurements at the refurbished Z machine

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

    Jones, M. C.; Ampleford, D. J.; Cuneo, M. E.; Hohlfelder, R.; Jennings, C. A.; Johnson, D. W.; Jones, B.; Lopez, M. R.; MacArthur, J.; Mills, J. A.; et al

    2014-08-04

    Advancements have been made in the diagnostic techniques to measure accurately the total radiated x-ray yield and power from z-pinch loads at the Z Machine with high accuracy. The Z-accelerator is capable of outputting 2MJ and 330 TW of x-ray yield and power, and accurately measuring these quantities is imperative. We will describe work over the past several years which include the development of new diagnostics, improvements to existing diagnostics, and implementation of automated data analysis routines. A set of experiments were conducted on the Z machine where the load and machine configuration were held constant. During this shot series,more » it was observed that total z-pinch x-ray emission power determined from the two common techniques for inferring the x-ray power, Kimfol filtered x-ray diode diagnostic and the Total Power and Energy diagnostic gave 450 TW and 327 TW respectively. Our analysis shows the latter to be the more accurate interpretation. More broadly, the comparison demonstrates the necessity to consider spectral response and field of view when inferring xray powers from z-pinch sources.« less

  7. X-ray structure determination using low-resolution electron microscopy maps for molecular replacement

    SciTech Connect (OSTI)

    Jackson, Ryan N.; McCoy, Airlie J.; Terwilliger, Thomas C.; Read, Randy J.; Wiedenheft, Blake

    2015-07-30

    Structures of multi-subunit macromolecular machines are primarily determined by either electron microscopy (EM) or X-ray crystallography. In many cases, a structure for a complex can be obtained at low resolution (at a coarse level of detail) with EM and at higher resolution (with finer detail) by X-ray crystallography. The integration of these two structural techniques is becoming increasingly important for generating atomic models of macromolecular complexes. A low-resolution EM image can be a powerful tool for obtaining the "phase" information that is missing from an X-ray crystallography experiment, however integration of EM and X-ray diffraction data has been technically challenging. Here we show a step-by-step protocol that explains how low-resolution EM maps can be placed in the crystallographic unit cell by molecular replacement, and how initial phases computed from the placed EM density are extended to high resolution by averaging maps over non-crystallographic symmetry. As the resolution gap between EM and Xray crystallography continues to narrow, the use of EM maps to help with X-ray crystal structure determination, as described in this protocol, will become increasingly effective.

  8. UNIVERSAL BEHAVIOR OF X-RAY FLARES FROM BLACK HOLE SYSTEMS

    SciTech Connect (OSTI)

    Wang, F. Y.; Dai, Z. G.; Yi, S. X.; Xi, S. Q. E-mail: dzg@nju.edu.cn

    2015-01-01

    X-ray flares have been discovered in black hole systems such as gamma-ray bursts, the tidal disruption event Swift J1644+57, the supermassive black hole Sagittarius A* at the center of our Galaxy, and some active galactic nuclei. Occurrences of X-ray flares are always accompanied by relativistic jets. However, it is still unknown whether or not there is a physical analogy among such X-ray flares produced in black hole systems spanning nine orders of magnitude in mass. Here, we report observed data of X-ray flares and show that they have three statistical properties similar to solar flares, including power-law distributions of their energies, durations, and waiting times, which can be explained by a fractal-diffusive, self-organized criticality model. These statistical similarities, together with the fact that solar flares are triggered by a magnetic reconnection process, suggest that all of the X-ray flares are consistent with magnetic reconnection events, implying that their concomitant relativistic jets may be magnetically dominated.

  9. Recollimation boundary layers as X-ray sources in young stellar jets

    SciTech Connect (OSTI)

    Gnther, Hans Moritz; Li, Zhi-Yun; Schneider, P. C.

    2014-11-01

    Young stars accrete mass from circumstellar disks and, in many cases, the accretion coincides with a phase of massive outflows, which can be highly collimated. Those jets emit predominantly in the optical and IR wavelength range. However, in several cases, X-ray and UV observations reveal a weak but highly energetic component in those jets. X-rays are observed both from stationary regions close to the star and from knots in the jet several hundred AU from the star. In this article, we show semianalytically that a fast stellar wind that is recollimated by the pressure from a slower, more massive disk wind can have the right properties to power stationary X-ray emission. The size of the shocked regions is compatible with observational constraints. Our calculations support a wind-wind interaction scenario for the high-energy emission near the base of young stellar object jets. For the specific case of DG Tau, a stellar wind with a mass-loss rate of 5 10{sup 10} M {sub ?} yr{sup 1} and a wind speed of 800 km s{sup 1} reproduces the observed X-ray spectrum. We conclude that a stellar wind recollimation shock is a viable scenario to power stationary X-ray emission close to the jet launching point.

  10. A NEW COSMOLOGICAL DISTANCE MEASURE USING ACTIVE GALACTIC NUCLEUS X-RAY VARIABILITY

    SciTech Connect (OSTI)

    Franca, Fabio La; Bianchi, Stefano; Branchini, Enzo; Matt, Giorgio [Dipartimento di Matematica e Fisica, Universit Roma Tre, Via della Vasca Navale 84, I-00146, Roma (Italy); Ponti, Gabriele, E-mail: lafranca@fis.uniroma3.it [Max-Planck-Institut fr Extraterrestrische Physik, Giessenbachstrasse 1, D-85748 Garching bei Mnchen (Germany)

    2014-05-20

    We report the discovery of a luminosity distance estimator using active galactic nuclei (AGNs). We combine the correlation between the X-ray variability amplitude and the black hole (BH) mass with the single-epoch spectra BH mass estimates which depend on the AGN luminosity and the line width emitted by the broad-line region. We demonstrate that significant correlations do exist that allow one to predict the AGN (optical or X-ray) luminosity as a function of the AGN X-ray variability and either the H? or the Pa? line widths. In the best case, when the Pa? is used, the relationship has an intrinsic dispersion of ?0.6dex. Although intrinsically more disperse than supernovae Ia, this relation constitutes an alternative distance indicator potentially able to probe, in an independent way, the expansion history of the universe. With respect to this, we show that the new mission concept Athena should be able to measure the X-ray variability of hundreds of AGNs and then constrain the distance modulus with uncertainties of 0.1mag up to z ? 0.6. We also discuss how our estimator has the prospect of becoming a cosmological probe even more sensitive than the current supernovae Ia samples by using a new dedicated wide-field X-ray telescope able to measure the variability of thousands of AGNs.

  11. X-ray tests of a two-dimensional stigmatic imaging scheme with variable magnifications

    SciTech Connect (OSTI)

    Lu, J.; Bitter, M.; Hill, K. W.; Delgado-Aparicio, L. F.; Efthimion, P. C.; Pablant, N. A.; Beiersdorfer, P.; Caughey, T. A.; Brunner, J.

    2014-11-15

    A two-dimensional stigmatic x-ray imaging scheme, consisting of two spherically bent crystals, one concave and one convex, was recently proposed [M. Bitter et al., Rev. Sci. Instrum. 83, 10E527 (2012)]. The Bragg angles and the radii of curvature of the two crystals of this imaging scheme are matched to eliminate the astigmatism and to satisfy the Bragg condition across both crystal surfaces for a given x-ray energy. In this paper, we consider more general configurations of this imaging scheme, which allow us to vary the magnification for a given pair of crystals and x-ray energy. The stigmatic imaging scheme has been validated for the first time by imaging x-rays generated by a micro-focus x-ray source with source size of 8.4 ?m validated by knife-edge measurements. Results are presented from imaging the tungsten L?1 emission at 8.3976 keV, using a convex Si-422 crystal and a concave Si-533 crystal with 2d-spacings of 2.21707 and 1.65635 and radii of curvature of 500 1 mm and 823 1 mm, respectively, showing a spatial resolution of 54.9 ?m. This imaging scheme is expected to be of interest for the two-dimensional imaging of laser produced plasmas.

  12. X-ray structure determination using low-resolution electron microscopy maps for molecular replacement

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

    Jackson, Ryan N.; McCoy, Airlie J.; Terwilliger, Thomas C.; Read, Randy J.; Wiedenheft, Blake

    2015-07-30

    Structures of multi-subunit macromolecular machines are primarily determined by either electron microscopy (EM) or X-ray crystallography. In many cases, a structure for a complex can be obtained at low resolution (at a coarse level of detail) with EM and at higher resolution (with finer detail) by X-ray crystallography. The integration of these two structural techniques is becoming increasingly important for generating atomic models of macromolecular complexes. A low-resolution EM image can be a powerful tool for obtaining the "phase" information that is missing from an X-ray crystallography experiment, however integration of EM and X-ray diffraction data has been technically challenging.more » Here we show a step-by-step protocol that explains how low-resolution EM maps can be placed in the crystallographic unit cell by molecular replacement, and how initial phases computed from the placed EM density are extended to high resolution by averaging maps over non-crystallographic symmetry. As the resolution gap between EM and Xray crystallography continues to narrow, the use of EM maps to help with X-ray crystal structure determination, as described in this protocol, will become increasingly effective.« less

  13. Runaway electron energy measurement using hard x-ray spectroscopy in 'Damavand' tokamak

    SciTech Connect (OSTI)

    Rasouli, C.; Farahbod, A. H.; Rasouli, H.; Lamehi, M.; Iraji, D.; Akhtari, K.; Modarresi, H.

    2009-01-15

    Set of experiments has been developed to study existing runaway electrons in ''Damavand'' tokamak plasma upon characteristics of hard x-ray emissions produced by collision of the runaway electrons with the plasma particles and limiters. As a first step, spatial distribution of hard x-ray emissions on the equatorial plane of the torus was considered. Obtained spectra of hard x-ray emissions for different alignments of shielded detector indicate isotropic emissivity in the equatorial plane. This is in agreement with wide angle cone of bremsstrahlung radiations, deduced from the mean value of energy of the runaway electrons. The mean energy was calculated from the slope of the energy spectrum of hard x-ray photons. In the second stage in order to investigate time evolution of energy of the runaway electrons, similar technique were applied to obtain hard x-ray energy in every 3 ms intervals, from the beginning to the end of plasma. The mean energy of the runaway electrons increases during the ramp up phase and reaches its maximum between 3 and 9 ms after plasma formation. Also considering the time dependence of the counted photons in each energy range shows that energetic photons are emitted during the ramp up phase of the plasma current in Damavand tokamak.

  14. Characteristics of a molybdenum X-pinch X-ray source as a probe source for X-ray diffraction studies

    SciTech Connect (OSTI)

    Zucchini, F.; Chauvin, C.; Combes, P.; Sol, D.; Loyen, A.; Roques, B.; Grunenwald, J.; Bland, S. N.

    2015-03-15

    X-ray emission from a molybdenum X-pinch has been investigated as a potential probe for the high pressure states made in dynamic compression experiments. Studies were performed on a novel 300 kA, 400 ns generator which coupled the load directly to a low inductance capacitor and switch combination. The X-pinch load consisted of 4 crossed molybdenum wires of 13 μm diameter, crossed at an angle of 62°. The load height was 10 mm. An initial x-ray burst generated at the wire crossing point, radiated in the soft x-ray range (hυ < 10 keV). This was followed, 2–5 ns later, by at least one harder x-ray burst (hυ > 10 keV) whose power ranged from 1 to 7 MW. Time integrated spectral measurements showed that the harder bursts were dominated by K-alpha emission; though, a lower level, wide band continuum up to at least 30 keV was also present. Initial tests demonstrated that the source was capable of driving Laue diffraction experiments, probing uncompressed samples of LiF and aluminium.

  15. Broadband high resolution X-ray spectral analyzer

    DOE Patents [OSTI]

    Silver, Eric H.; Legros, Mark; Madden, Norm W.; Goulding, Fred; Landis, Don

    1998-01-01

    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.

  16. Broadband high resolution X-ray spectral analyzer

    DOE Patents [OSTI]

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

    1998-07-07

    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.

  17. Advances in x-ray computed microtomography at the NSLS

    SciTech Connect (OSTI)

    Dowd, B.A.; Andrews, A.B.; Marr, R.B.; Siddons, D.P.; Jones, K.W.; Peskin, A.M.

    1998-08-01

    The X-Ray Computed Microtomography workstation at beamline X27A at the NSLS has been utilized by scientists from a broad range of disciplines from industrial materials processing to environmental science. The most recent applications are presented here as well as a description of the facility that has evolved to accommodate a wide variety of materials and sample sizes. One of the most exciting new developments reported here resulted from a pursuit of faster reconstruction techniques. A Fast Filtered Back Transform (FFBT) reconstruction program has been developed and implemented, that is based on a refinement of the gridding algorithm first developed for use with radio astronomical data. This program has reduced the reconstruction time to 8.5 sec for a 929 x 929 pixel{sup 2} slice on an R10,000 CPU, more than 8x reduction compared with the Filtered Back-Projection method.

  18. Transverse Coherence of the LCLS X-Ray Beam

    SciTech Connect (OSTI)

    Not Available

    2010-12-01

    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.

  19. X-ray studies of concentrated aqueous solutions

    SciTech Connect (OSTI)

    Ludwig, K.F. Jr.; Warburton, W.K.; Fontaine, A.

    1987-07-01

    Concentrated aqueous solutions of three transition metal bromides (ZnBr/sub 2/, CuBr/sub 2/, and NiBr/sub 2/) and an alkali bromide (RbBr) have been studied with differential anomalous scattering (DAS) and extended x-ray absorption fine structure (EXAFS). The aq-ZnBr/sub 2/ solutions exhibit considerable inner-shell ion complexing with the formation of tetrahedral complexes about the Zn/sup 2 +/. In aq-CuBr/sub 2/, the Cu/sup 2 +/ has an octahedral coordination shell. Most of the anions are bound directly to the cations in both solutions. In contrast, there are only a few Ni--Br nearest neighbors in aq-NiBr/sub 2/. Instead, cations and anions share hydrating water molecules. Preliminary data show that any ion complexing in aq-RbBr must be weak. These results are in good agreement with published thermodynamic studies.

  20. Apparatus for generating x-ray holograms

    DOE Patents [OSTI]

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

    1990-09-11

    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.

  1. Apparatus for generating x-ray holograms

    DOE Patents [OSTI]

    Rhodes, Charles K.; Boyer, Keith; Solem, Johndale C.; Haddad, Waleed S.

    1990-01-01

    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.

  2. The X-Ray Microcalorimeter Spectrometer for the International X-Ray Observatory

    SciTech Connect (OSTI)

    Kelley, R. L.; Bandler, S. R.; Kilbourne, C. A.; Porter, F. S.; Shirron, P.; Smith, S. J.; Whitehouse, P.; Ezoe, Y.; Ishisaki, Y.; Ohashi, T.; Fujimoto, R.; Sato, K.; Gottardi, L.; Hartog, R. den; Herder, J.-W. den; Hoevers, H.; Korte, P. de; Kuur, J. van der

    2009-12-16

    The International X-Ray Observatory (IXO) is under formulation by NASA, ESA and JAXA for deployment in 2022. IXO emerged over the last 18 months as the NASA Constellation-X and ESA/JAXA X-Ray Evolving Universe Spectrometer (XEUS) missions were combined. The driving performance requirements for the X-Ray Microcalorimeter Spectrometer (XMS) are a spectral resolution of 2.5 eV over the central 2'x2' in the 0.3-7.0 keV band, and 10 eV to the edge of the 5'x5' field of view (FOV). The XMS is now based on a microcalorimeter array of Transition-Edge Sensor (TES) thermometers with Au/Bi absorbers and a SQUID MUX readout. One of the concepts studied as part of the mission formulation has a core 40x40 array corresponding to a 2'x2' FOV with 3'' pixels surrounded by an outer, annular 52x52 array of 6'' pixels that extends the field of view to 5.4'x5.4' with better than 10 eV resolution. There are several options for implementing the readout and cooling system of the XMS under study in the US, Europe and Japan. The ADR system will have from two to five stages depending on the performance of the cryocooler. Mechanical coolers with sufficient cooling power at 4K are available now, and {approx}2K coolers are under development. In this paper we give an overview of the XMS instrument, and some of the tradeoffs to be addressed for this observatory instrument.

  3. Sensitivity Analysis of X-ray Spectra from Scanning Electron Microscopes

    SciTech Connect (OSTI)

    Miller, Thomas Martin; Patton, Bruce W.; Weber, Charles F.; Bekar, Kursat B.

    2014-10-01

    The primary goal of this project is to evaluate x-ray spectra generated within a scanning electron microscope (SEM) to determine elemental composition of small samples. This will be accomplished by performing Monte Carlo simulations of the electron and photon interactions in the sample and in the x-ray detector. The elemental inventories will be determined by an inverse process that progressively reduces the difference between the measured and simulated x-ray spectra by iteratively adjusting composition and geometric variables in the computational model. The intended benefit of this work will be to develop a method to perform quantitative analysis on substandard samples (heterogeneous phases, rough surfaces, small sizes, etc.) without involving standard elemental samples or empirical matrix corrections (i.e., true standardless quantitative analysis).

  4. In Situ X-Ray Probing Reveals Fingerprints of Surface Platinum Oxide

    SciTech Connect (OSTI)

    Friebel, Daniel

    2011-08-24

    In situ x-ray absorption spectroscopy (XAS) at the Pt L{sub 3} edge is a useful probe for Pt-O interactions at polymer electrolyte membrane fuel cell (PEMFC) cathodes. We show that XAS using the high energy resolution fluorescence detection (HERFD) mode, applied to a well-defined monolayer Pt/Rh(111) sample where the bulk penetrating hard x-rays probe only surface Pt atoms, provides a unique sensitivity to structure and chemical bonding at the Pt-electrolyte interface. Ab initio multiple-scattering calculations using the FEFF8 code and complementary extended x-ray absorption fine structure (EXAFS) results indicate that the commonly observed large increase of the white-line at high electrochemical potentials on PEMFC cathodes originates from platinum oxide formation, whereas previously proposed chemisorbed oxygen-containing species merely give rise to subtle spectral changes.

  5. Development of all-solid-state flash x-ray generator with photoconductive semiconductor switches

    SciTech Connect (OSTI)

    Xun, Ma; Jianjun, Deng; Hongwei, Liu; Jianqiang, Yuan; Jinfeng, Liu; Bing, Wei; Yanling, Qing; Wenhui, Han; Lingyun, Wang; Pin, Jiang; Hongtao, Li

    2014-09-15

    A compact, low-jitter, and high repetitive rate all-solid-state flash x-ray generator making use of photo conductive semiconductor switches was developed recently for the diagnostic purpose of some hydrokinetical experiments. The generator consisted of twelve stages of Blumlein pulse forming networks, and an industrial cold cathode diode was used to generate intense x-ray radiations with photon energy up to 220 keV. Test experiments showed that the generator could produce >1 kA electron beam currents and x-ray pulses with ?40 ns duration under 100 Hz repetitive rates at least (limited by the triggering laser on hand), also found was that the delay time of the cathode explosive emission is crucial to the energy transfer efficiency of the whole system. In addition, factors affecting the diode impedance, how the switching synchronization and diode impedance determining the allowable operation voltage were discussed.

  6. Enhancement of x-rays generated by a guided laser wakefield accelerator inside capillary tubes

    SciTech Connect (OSTI)

    Ju, J.; Doepp, A.; Cassou, K.; Neveu, O.; Cros, B.; Svensson, K.; Genoud, G.; Wojda, F.; Burza, M.; Persson, A.; Lundh, O.; Wahlstroem, C.-G.; Ferrari, H. E.

    2012-05-07

    Electrons accelerated in the nonlinear regime in a laser wakefield accelerator experience transverse oscillations inside the plasma cavity, giving rise to ultra-short pulsed x-rays, also called the betatron radiation. We show that the fluence of x-ray can be enhanced by more than one order of magnitude when the laser is guided by a 10 mm long capillary tube instead of interacting with a 2 mm gas jet. X-rays with a synchrotron-like spectrum and associated critical energy {approx}5 keV, with a peak brightness of {approx}1x10{sup 21} ph/s/mm{sup 2}/mrad{sup 2}/0.1%BW, were achieved by employing 16 TW laser pulses.

  7. Demonstration of x-ray fluorescence imaging of a high-energy-density plasma

    SciTech Connect (OSTI)

    MacDonald, M. J. Gamboa, E. J.; Keiter, P. A.; Fein, J. R.; Klein, S. R.; Kuranz, C. C.; LeFevre, H. J.; Manuel, M. J.-E.; Wan, W. C.; Drake, R. P.; Montgomery, D. S.; Biener, M. M.; Fournier, K. B.; Streit, J.

    2014-11-15

    Experiments at the Trident Laser Facility have successfully demonstrated the use of x-ray fluorescence imaging (XRFI) to diagnose shocked carbonized resorcinol formaldehyde (CRF) foams doped with Ti. One laser beam created a shock wave in the doped foam. A second laser beam produced a flux of vanadium He-α x-rays, which in turn induced Ti K-shell fluorescence within the foam. Spectrally resolved 1D imaging of the x-ray fluorescence provided shock location and compression measurements. Additionally, experiments using a collimator demonstrated that one can probe specific regions within a target. These results show that XRFI is a capable alternative to path-integrated measurements for diagnosing hydrodynamic experiments at high energy density.

  8. Feasibility test of Z{sub eff} imaging using x-ray interferometry

    SciTech Connect (OSTI)

    Yoneyama, Akio; Hyodo, Kazuyuki; Takeda, Tohoru

    2013-11-11

    Elemental imaging using X-ray interferometry has been developed. Since the atomic number (Z) of a single-element sample (effective atomic number (Z{sub eff}) for a plural-element sample) corresponds to the ratio of the real to imaginary part of the complex refractive index, an elemental map is calculable with the ratio of an absorption and phase-contrast image. Several metal foils underwent feasibility observations by crystal X-ray interferometry, providing accurate detection of X-ray intensity and phase-shift. The obtained Z{sub eff} image shows that aluminum, iron, nickel, and copper foil were clearly distinguished, and nickel and copper's Z{sub eff} values coincide with ideal Z number within 1%.

  9. Theoretical analysis of the background intensity distribution in X-ray Birefringence Imaging using synchrotron bending-magnet radiation

    SciTech Connect (OSTI)

    Sutter, John P. Dolbnya, Igor P.; Collins, Stephen P.; Harris, Kenneth D. M.; Edwards-Gau, Gregory R.; Palmer, Benjamin A.

    2015-04-28

    In the recently developed technique of X-ray Birefringence Imaging, molecular orientational order in anisotropic materials is studied by exploiting the birefringence of linearly polarized X-rays with energy close to an absorption edge of an element in the material. In the experimental setup, a vertically deflecting high-resolution double-crystal monochromator is used upstream from the sample to select the appropriate photon energy, and a horizontally deflecting X-ray polarization analyzer, consisting of a perfect single crystal with a Bragg reflection at Bragg angle of approximately 45°, is placed downstream from the sample to measure the resulting rotation of the X-ray polarization. However, if the experiment is performed on a synchrotron bending-magnet beamline, then the elliptical polarization of the X-rays out of the electron orbit plane affects the shape of the output beam. Also, because the monochromator introduces a correlation between vertical position and photon energy to the X-ray beam, the polarization analyzer does not select the entire beam, but instead selects a diagonal stripe, the slope of which depends on the Bragg angles of the monochromator and the polarization analyzer. In the present work, the final background intensity distribution is calculated analytically because the phase space sampling methods normally used in ray traces are too inefficient for this setup. X-ray Birefringence Imaging data measured at the Diamond Light Source beamline B16 agree well with the theory developed here.

  10. Controlling the spectrum of x-rays generated in a laser-plasma accelerator by tailoring the laser wavefront

    SciTech Connect (OSTI)

    Mangles, S. P. D.; Kneip, S.; Dover, N. P.; Najmudin, Z.; Schreiber, J.; Genoud, G.; Burza, M.; Kamperidis, C.; Persson, A.; Wahlstroem, C.-G.; Cassou, K.; Cros, B.; Wojda, F.

    2009-11-02

    By tailoring the wavefront of the laser pulse used in a laser-wakefield accelerator, we show that the properties of the x-rays produced due to the electron beam's betatron oscillations in the plasma can be controlled. By creating a wavefront with coma, we find that the critical energy of the synchrotronlike x-ray spectrum can be significantly increased. The coma does not substantially change the energy of the electron beam, but does increase its divergence and produces an energy-dependent exit angle, indicating that changes in the x-ray spectrum are due to an increase in the electron beam's oscillation amplitude within the wakefield.

  11. An x-ray setup to investigate the atomic order of confined liquids in slit geometry

    SciTech Connect (OSTI)

    Lippmann, M.; Ehnes, A.; Seeck, O. H.

    2014-01-15

    A setup has been designed to investigate thin films of confined liquids with the use of X-ray scattering methods. The confinement is realized between the flat culets of a pair of diamonds by positioning and orienting the lower diamond with nanometer and micro radian accuracy. We routinely achieve gaps between 5 and 50 nm at culet diameters of 200 ?m. With this setup and a micro focused X-ray beam we have investigated the in-plane and the out-off-plane atomic order of benzene with atomic resolution.

  12. The X-ray PumpProbe instrument at the LinacCoherent Light Source

    SciTech Connect (OSTI)

    Chollet, Matthieu; Alonso-Mori, Roberto; Cammarata, Marco; Damiani, Daniel; Defever, Jim; Delor, James T.; Feng, Yiping; Glownia, James M.; Langton, J. Brian; Nelson, Silke; Ramsey, Kelley; Robert, Aymeric; Sikorski, Marcin; Song, Sanghoon; Stefanescu, Daniel; Srinivasan, Venkat; Zhu, Diling; Lemke, Henrik T.; Fritz, David M.

    2015-04-21

    The X-ray PumpProbe instrument achieves femtosecond time-resolution with hard X-ray methods using a free-electron laser source. It covers a photon energy range of 424 keV. A femtosecond optical laser system is available across a broad spectrum of wavelengths for generating transient states of matter. The instrument is designed to emphasize versatility and the scientific goals encompass ultrafast physical, chemical and biological processes involved in the transformation of matter and transfer of energy at the atomic scale.

  13. Pulse energy measurement at the hard x-ray laser in Japan

    SciTech Connect (OSTI)

    Kato, M.; Tanaka, T.; Saito, N.; Kurosawa, T.; Richter, M.; Sorokin, A. A.; Tiedtke, K.; Kudo, T.; Yabashi, M.; Tono, K.; Ishikawa, T.

    2012-07-09

    The pulse energies of a free electron laser have accurately been measured in the hard x-ray spectral range. In the photon energy regime from 4.4 keV to 16.8 keV, pulse energies up to 100 {mu}J were obtained at the hard x-ray laser facility SACLA (SPring-8 Angstrom Compact free-electron LAser). Two independent methods, using a cryogenic radiometer and a gas monitor detector, were applied and agreement within 3.3% was achieved. Based on our validated pulse energy measurement, a SACLA online monitor detector could be calibrated for all future experiments.

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

    DOE Patents [OSTI]

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

    2008-06-08

    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.

  15. The X-ray Pump–Probe instrument at the Linac Coherent Light Source

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

    Chollet, Matthieu; Alonso-Mori, Roberto; Cammarata, Marco; Damiani, Daniel; Defever, Jim; Delor, James T.; Feng, Yiping; Glownia, James M.; Langton, J. Brian; Nelson, Silke; et al

    2015-04-21

    The X-ray Pump–Probe instrument achieves femtosecond time-resolution with hard X-ray methods using a free-electron laser source. It covers a photon energy range of 4–24 keV. A femtosecond optical laser system is available across a broad spectrum of wavelengths for generating transient states of matter. The instrument is designed to emphasize versatility and the scientific goals encompass ultrafast physical, chemical and biological processes involved in the transformation of matter and transfer of energy at the atomic scale.

  16. 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.

    2007-04-24

    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.

  17. Study of the internal structure of lithium fluoride single crystal by laboratory X-ray topo-tomography

    SciTech Connect (OSTI)

    Zolotov, D. A. Buzmakov, A. V.; Asadchikov, V. E.; Voloshin, A. E.; Shkurko, V. N.; Smirnov, I. S.

    2011-05-15

    Defects in a synthetic LiF crystal have been studied by X-ray topo-tomography on laboratory X-ray sources with a spatial resolution of {approx}10 {mu}m. An algebraic reconstruction method was applied to reconstruct the defect 3D structure of the crystal based on the diffraction data. The results presented in this study are in good agreement with the topographic data obtained by the Lang method.

  18. Determination of the polarization state of x rays with the help of anomalous transmission

    SciTech Connect (OSTI)

    Schulze, K. S. Uschmann, I.; Frster, E.; Marx, B.; Paulus, G. G.; Sthlker, T.

    2014-04-14

    Besides intensity and direction, the polarization of an electromagnetic wave provides characteristic information on the crossed medium. Here, we present two methods for the determination of the polarization state of x rays by polarizers based on anomalous transmission (Borrmann effect). Using a polarizer-analyzer setup, we have measured a polarization purity of less than 1.5??10{sup ?5}, three orders of magnitude better than obtained in earlier work. Using the analyzer crystal in multiple-beam case with slightly detuned azimuth, we show how the first three Stokes parameters can be determined with a single angular scan. Thus, polarization analyzers based on anomalous transmission make it possible to detect changes of the polarization in a range from degrees down to arcseconds.

  19. Hard X-ray spatial array diagnostics on Joint Texas Experimental Tokamak

    SciTech Connect (OSTI)

    Huang, D. W.; Chen, Z. Y. Luo, Y. H.; Tong, R. H.; Yan, W.; Jin, W.; Zhuang, G.

    2014-11-15

    A spatially distributed hard X-ray detection array has been developed to diagnose the loss of runaway electron with toroidal and poloidal resolution. The hard X-ray radiation in the energy ranges of 0.31 MeV resulted from runaway electrons can be measured. The detection array consists of 12 CdTe detectors which are arranged surrounding the tokamak. It is found that most runaway electrons which transport to plasma boundary tend to loss on limiters. The application of electrode biasing probe resulted in enhancement of local runaway loss. Resonant magnetic perturbations enhanced the runaway electrons diffusion and showed an asymmetric poloidal loss rate.

  20. Hexakis(4-phormylphenoxy)cyclotriphosphazene: X-ray and DFT-calculated structures

    SciTech Connect (OSTI)

    Albayrak, Cigdem Kosar, Basak; Odabasoglu, Mustafa; Bueyuekguengoer, Orhan

    2010-12-15

    The crystal structure of hexakis(4-phormylphenoxy)cyclotriphosphazene is determined by using X-ray diffraction and then the molecular structure is investigated with density functional theory (DFT). X-Ray study shows that the title compound has C-H-{pi} interaction with phosphazene ring. The molecules in the unit cell are packed with Van der Waals and dipole-dipole interactions and the molecules are packed in zigzag shaped. Optimized molecular geometry is calculated with DFT at B3LYP/6-311G(d,p) level. The results from both experimental and theoretical calculations are compared in this study.