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Sample records for focused x-ray beam

  1. Nanoparticle-Assisted Scanning Focusing X-Ray Therapy with Needle Beam X Rays.

    Science.gov (United States)

    Davidson, R Andrew; Guo, Ting

    2016-01-01

    In this work, we show a new therapeutic approach using 40-120 keV X rays to deliver a radiation dose at the isocenter located many centimeters below the skin surface several hundred times greater than at the skin and how this dose enhancement can be augmented with nanomaterials to create several thousand-fold total dose enhancement effect. This novel approach employs a needle X-ray beam directed at the isocenter centimeters deep in the body while continuously scanning the beam to cover a large solid angle without overlapping at the skin. A Monte Carlo method was developed to simulate an X-ray dose delivered to the isocenter filled with X-ray absorbing and catalytic nanoparticles in a water phantom. An experimental apparatus consisting of a moving plastic phantom irradiated with a stationary 1 mm needle X-ray beam was built to test the theoretical predictions. X-ray films were used to characterize the dose profiles of the scanning X-ray apparatus. Through this work, it was determined that the X-ray dose delivered to the isocenter in a treatment voxel (t-voxel) underneath a 5 cm deep high-density polyethylene (HDPE) phantom was 295 ± 48 times greater than the surface dose. This measured value was in good agreement with the theoretical predicted value of 339-fold. Adding X-ray-absorbing nanoparticles, catalytic nanoparticles or both into the t-voxel can further augment the dose enhancement. For example, we predicted that adding 1 weight percentage (wp) of gold into water could increase the effective dose delivered to the target by onefold. Dose enhancement using 1 mm X-ray beam could reach about 1,600-fold in the t-voxel when 7.5 wp of 88 nm diameter silica-covered gold nanoparticles were added, which we showed in a previously published study can create a dose enhancement of 5.5 ± 0.46-fold without scanning focusing enhancement. Based on the experimental data from that study, mixing 0.02 wp 2.5 nm diameter small tetrakis hydroxymethyl phosphonium chloride (THPC

  2. Editorial: Focus on X-ray Beams with High Coherence

    Science.gov (United States)

    Robinson, Ian; Gruebel, Gerhard; Mochrie, Simon

    2010-03-01

    This editorial serves as the preface to a special issue of New Journal of Physics, which collects together solicited papers on a common subject, x-ray beams with high coherence. We summarize the issue's content, and explain why there is so much current interest both in the sources themselves and in the applications to the study of the structure of matter and its fluctuations (both spontaneous and driven). As this collection demonstrates, the field brings together accelerator physics in the design of new sources, particle physics in the design of detectors, and chemical and materials scientists who make use of the coherent beams produced. Focus on X-ray Beams with High Coherence Contents Femtosecond pulse x-ray imaging with a large field of view B Pfau, C M Günther, S Schaffert, R Mitzner, B Siemer, S Roling, H Zacharias, O Kutz, I Rudolph, R Treusch and S Eisebitt The FERMI@Elettra free-electron-laser source for coherent x-ray physics: photon properties, beam transport system and applications E Allaria, C Callegari, D Cocco, W M Fawley, M Kiskinova, C Masciovecchio and F Parmigiani Beyond simple exponential correlation functions and equilibrium dynamics in x-ray photon correlation spectroscopy Anders Madsen, Robert L Leheny, Hongyu Guo, Michael Sprung and Orsolya Czakkel The Coherent X-ray Imaging (CXI) instrument at the Linac Coherent Light Source (LCLS) Sébastien Boutet and Garth J Williams Dynamics and rheology under continuous shear flow studied by x-ray photon correlation spectroscopy Andrei Fluerasu, Pawel Kwasniewski, Chiara Caronna, Fanny Destremaut, Jean-Baptiste Salmon and Anders Madsen Exploration of crystal strains using coherent x-ray diffraction Wonsuk Cha, Sanghoon Song, Nak Cheon Jeong, Ross Harder, Kyung Byung Yoon, Ian K Robinson and Hyunjung Kim Coherence properties of the European XFEL G Geloni, E Saldin, L Samoylova, E Schneidmiller, H Sinn, Th Tschentscher and M Yurkov Fresnel coherent diffractive imaging: treatment and analysis of data G J

  3. Nano-fabrication of diffractive optics for soft X-ray and atom beam focusing

    International Nuclear Information System (INIS)

    Rehbein, S.

    2002-01-01

    Nano-structuring processes are described for manufacturing diffractive optics for the condenser-monochromator set-up of the transmission X-ray microscope (TXM) and for the scanning transmission X-ray microscope (STXM) at the BESSY II electron storage ring in Berlin. Furthermore, a process for manufacturing free-standing nickel zone plates for helium atom beam focusing experiments is presented. (author)

  4. Measurements of fast electron beams and soft X-ray emission from plasma-focus experiments

    Directory of Open Access Journals (Sweden)

    Surała Władysław

    2016-06-01

    Full Text Available The paper reports results of the recent experimental studies of pulsed electron beams and soft X-rays in plasma-focus (PF experiments carried out within a modified PF-360U facility at the NCBJ, Poland. Particular attention was focused on time-resolved measurements of the fast electron beams by means of two different magnetic analyzers, which could record electrons of energy ranging from about 41 keV to about 715 keV in several (6 or 8 measuring channels. For discharges performed with the pure deuterium filling, many strong electron signals were recorded in all the measuring channels. Those signals were well correlated with the first hard X-ray pulse detected by an external scintillation neutron-counter. In some of the analyzer channels, electron spikes (lasting about dozens of nanoseconds and appearing in different instants after the current peculiarity (so-called current dip were also recorded. For several discharges, fast ion beams, which were emitted along the z-axis and recorded with nuclear track detectors, were also investigated. Those measurements confirmed a multibeam character of the ion emission. The time-integrated soft X-ray images, which were taken side-on by means of a pinhole camera and sensitive X-ray films, showed the appearance of some filamentary structures and so-called hot spots. The application of small amounts of admixtures of different heavy noble gases, i.e. of argon (4.8% volumetric, krypton (1.6% volumetric, or xenon (0.8% volumetric, decreased intensity of the recorded electron beams, but increased intensity of the soft X-ray emission and showed more distinct and numerous hot spots. The recorded electron spikes have been explained as signals produced by quasi-mono-energetic microbeams emitted from tiny sources (probably plasma diodes, which can be formed near the observed hot spots.

  5. New imaging technique based on diffraction of a focused x-ray beam

    Energy Technology Data Exchange (ETDEWEB)

    Kazimirov, A [Cornell High Energy Synchrotron Source (CHESS), Cornell University, Ithaca, NY 14853 (United States); Kohn, V G [Russian Research Center ' Kurchatov Institute, 123182 Moscow (Russian Federation); Cai, Z-H [Advanced Photon Source, 9700 S. Cass Avenue, Argonne, IL 60439 (United States)], E-mail: ayk7@cornell.edu

    2009-01-07

    We present first experimental results from a new diffraction depth-sensitive imaging technique. It is based on the diffraction of a focused x-ray beam from a crystalline sample and recording the intensity pattern on a high-resolution CCD detector positioned at a focal plane. Structural non-uniformity inside the sample results in a region of enhanced intensity in the diffraction pattern. The technique was applied to study silicon-on-insulator thin layers of various thicknesses which revealed a complex strain profile within the layers. A circular Fresnel zone plate was used as a focusing optic. Incoherent diffuse scattering spreads out of the diffraction plane and results in intensity recorded outside of the focal spot providing a new approach to separately register x-rays scattered coherently and incoherently from the sample. (fast track communication)

  6. In situ micro-focused X-ray beam characterization with a lensless camera using a hybrid pixel detector

    International Nuclear Information System (INIS)

    Kachatkou, Anton; Marchal, Julien; Silfhout, Roelof van

    2014-01-01

    Position and size measurements of a micro-focused X-ray beam, using an X-ray beam imaging device based on a lensless camera that collects radiation scattered from a thin foil placed in the path of the beam at an oblique angle, are reported. Results of studies on micro-focused X-ray beam diagnostics using an X-ray beam imaging (XBI) instrument based on the idea of recording radiation scattered from a thin foil of a low-Z material with a lensless camera are reported. The XBI instrument captures magnified images of the scattering region within the foil as illuminated by the incident beam. These images contain information about beam size, beam position and beam intensity that is extracted during dedicated signal processing steps. In this work the use of the device with beams for which the beam size is significantly smaller than that of a single detector pixel is explored. The performance of the XBI device equipped with a state-of-the-art hybrid pixel X-ray imaging sensor is analysed. Compared with traditional methods such as slit edge or wire scanners, the XBI micro-focused beam characterization is significantly faster and does not interfere with on-going experiments. The challenges associated with measuring micrometre-sized beams are described and ways of optimizing the resolution of beam position and size measurements of the XBI instrument are discussed

  7. Focusing of megaampere electron beam in gas cell for production of flash X-ray source

    Energy Technology Data Exchange (ETDEWEB)

    Zinchenko, Vl; Chlenov, A M; Shiyan, V D [Research Institute of Scientific Instruments, Turaevo-Lytkarino (Russian Federation)

    1997-12-31

    One of important problems to be solved in the development of an intense source of flash X-rays is the choice of the optimum design of the high-current diode at the exit of the electron accelerator. The results of numerical investigations of megaampere relativistic electron beam (REB) generation and focusing in a compound diode are discussed. The diode consists of a vacuum field-emission annular cathode, a planar anode, and a gas cell inserted between the anode foil and the target. (author). 2 figs., 5 refs.

  8. From x-ray telescopes to neutron scattering: Using axisymmetric mirrors to focus a neutron beam

    International Nuclear Information System (INIS)

    Khaykovich, B.; Gubarev, M.V.; Bagdasarova, Y.; Ramsey, B.D.; Moncton, D.E.

    2011-01-01

    We demonstrate neutron beam focusing by axisymmetric mirror systems based on a pair of mirrors consisting of a confocal ellipsoid and hyperboloid. Such a system, known as a Wolter mirror configuration, is commonly used in X-ray telescopes. The axisymmetric Wolter geometry allows nesting of several mirror pairs to increase collection efficiency. We implemented a system containing four nested Ni mirror pairs, which was tested by the focusing of a polychromatic neutron beam at the MIT Reactor. In addition, we have carried out extensive ray-tracing simulations of the mirrors and their performance in different situations. The major advantages of the Wolter mirrors are nesting for large angular collection and aberration-free performance. We discuss how these advantages can be utilized to benefit various neutron scattering methods, such as imaging, SANS, and time-of-flight spectroscopy.

  9. X-ray beam generator

    International Nuclear Information System (INIS)

    Koller, T.J.; Randmer, J.A.

    1977-01-01

    A method of minimizing the preferential angular absorption of the divergent beam from an X-ray generator is described. The generator consists of an X-ray shielded housing with an X-ray transmissive window symmetrically placed in radial alignment with a focal spot area on a sloped target surface of an X-ray tube in the housing. The X-ray tube may be of the stationary anode type or of the rotating anode type. (U.K.)

  10. High-pressure pair distribution function (PDF) measurement using high-energy focused x-ray beam

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Xinguo, E-mail: xhong@bnl.gov; Weidner, Donald J. [Mineral Physics Institute, Stony Brook University, Stony Brook, NY 11794 (United States); Ehm, Lars [Mineral Physics Institute, Stony Brook University, Stony Brook, NY 11794 (United States); National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973 (United States); Zhong, Zhong; Ghose, Sanjit [National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973 (United States); Duffy, Thomas S. [Department of Geosciences, Princeton University, Princeton, NJ 08544 (United States)

    2016-07-27

    In this paper, we report recent development of the high-pressure pair distribution function (HP-PDF) measurement technique using a focused high-energy X-ray beam coupled with a diamond anvil cell (DAC). The focusing optics consist of a sagittally bent Laue monochromator and Kirkpatrick-Baez (K–B) mirrors. This combination provides a clean high-energy X-ray beam suitable for HP-PDF research. Demonstration of the HP-PDF technique for nanocrystalline platinum under quasi-hydrostatic condition above 30 GPa is presented.

  11. Spot size characterization of focused non-Gaussian X-ray laser beams.

    Science.gov (United States)

    Chalupský, J; Krzywinski, J; Juha, L; Hájková, V; Cihelka, J; Burian, T; Vysín, L; Gaudin, J; Gleeson, A; Jurek, M; Khorsand, A R; Klinger, D; Wabnitz, H; Sobierajski, R; Störmer, M; Tiedtke, K; Toleikis, S

    2010-12-20

    We present a new technique for the characterization of non-Gaussian laser beams which cannot be described by an analytical formula. As a generalization of the beam spot area we apply and refine the definition of so called effective area (A(eff)) [1] in order to avoid using the full-width at half maximum (FWHM) parameter which is inappropriate for non-Gaussian beams. Furthermore, we demonstrate a practical utilization of our technique for a femtosecond soft X-ray free-electron laser. The ablative imprints in poly(methyl methacrylate) - PMMA and amorphous carbon (a-C) are used to characterize the spatial beam profile and to determine the effective area. Two procedures of the effective area determination are presented in this work. An F-scan method, newly developed in this paper, appears to be a good candidate for the spatial beam diagnostics applicable to lasers of various kinds.

  12. Spot size characterization of focused non-Gaussian X-ray laser beams

    Czech Academy of Sciences Publication Activity Database

    Chalupský, Jaromír; Krzywinski, J.; Juha, Libor; Hájková, Věra; Cihelka, Jaroslav; Burian, Tomáš; Vyšín, Luděk; Gaudin, J.; Gleeson, A.; Jurek, M.; Khorsand, A.R.; Klinger, D.; Wabnitz, H.; Sobierajski, R.; Störmer, M.; Tiedtke, K.; Toleikis, S.

    2010-01-01

    Roč. 18, č. 26 (2010), s. 27836-27845 ISSN 1094-4087 R&D Projects: GA AV ČR KAN300100702; GA MŠk LC510; GA MŠk(CZ) LC528; GA ČR GAP208/10/2302; GA MŠk LA08024; GA AV ČR IAAX00100903; GA MŠk(CZ) ME10046 Institutional research plan: CEZ:AV0Z10100523 Keywords : X-ray laser * free-electron laser * beam characterization * ablation Subject RIV: BH - Optics, Masers, Lasers Impact factor: 3.749, year: 2010

  13. Laue lens for radiotherapy applications through a focused hard x-ray beam: a feasibility study on requirements and tolerances

    Science.gov (United States)

    Camattari, Riccardo

    2017-09-01

    Focusing a hard x-ray beam would represent an innovative technique for tumour treatment, since such a beam may deliver a dose to a tumour located at a given depth under the skin, sparing the surrounding healthy cells. A detailed study of a focusing system for hard x-ray aimed at radiotherapy is presented here. Such a focusing system, named Laue lens, exploits x-ray diffraction and consists of a series of crystals disposed as concentric rings capable of concentrating a flux of x-rays towards a focusing point. A feasibility study regarding the positioning tolerances of the crystalline optical elements has been carried out. It is shown that a Laue lens can effectively be used in the context of radiotherapy for tumour treatments provided that the mounting errors are below certain values, which are reachable in the modern micromechanics. An extended survey based on an analytical approach and on simulations is presented for precisely estimating all the contributions of each mounting error, analysing their effect on the focal spot of the Laue lens. Finally, a simulation for evaluating the released dose in a water phantom is shown.

  14. Application of focused-beam flat-sample method to synchrotron powder X-ray diffraction with anomalous scattering effect

    International Nuclear Information System (INIS)

    Tanaka, M; Katsuya, Y; Matsushita, Y

    2013-01-01

    The focused-beam flat-sample method (FFM), which is a method for high-resolution and rapid synchrotron X-ray powder diffraction measurements by combination of beam focusing optics, a flat shape sample and an area detector, was applied for diffraction experiments with anomalous scattering effect. The advantages of FFM for anomalous diffraction were absorption correction without approximation, rapid data collection by an area detector and good signal-to-noise ratio data by focusing optics. In the X-ray diffraction experiments of CoFe 2 O 4 and Fe 3 O 4 (By FFM) using X-rays near the Fe K absorption edge, the anomalous scattering effect between Fe/Co or Fe 2+ /Fe 3+ can be clearly detected, due to the change of diffraction intensity. The change of observed diffraction intensity as the incident X-ray energy was consistent with the calculation. The FFM is expected to be a method for anomalous powder diffraction.

  15. Characteristics of focused soft X-ray free-electron laser beam determined by ablation of organic molecular solids

    Czech Academy of Sciences Publication Activity Database

    Chalupský, Jaromír; Juha, Libor; Kuba, J.; Cihelka, Jaroslav; Hájková, Věra; Koptyaev, Sergey; Krása, Josef; Velyhan, Andriy; Bergh, M.; Caleman, C.; Hajdu, J.; Bionta, R.M.; Chapman, H.; Hau-Riege, S.P.; London, R.A.; Jurek, M.; Krzywinski, J.; Nietubyc, R.; Pelka, J. B.; Sobierajski, R.; Meyer-ter-Vehn, J.; Tronnier, A.; Sokolowski-Tinten, K.; Stojanovic, N.; Tiedtke, K.; Toleikis, S.; Tschentscher, T.; Wabnitz, H.; Zastrau, U.

    2007-01-01

    Roč. 15, č. 10 (2007), s. 6036-6042 ISSN 1094-4087 R&D Projects: GA MŠk 1P04LA235; GA MŠk LC510; GA MŠk(CZ) LC528; GA AV ČR KAN300100702 Grant - others:GA MŠk(CZ) 1K05026 Institutional research plan: CEZ:AV0Z10100523; CEZ:AV0Z40400503 Keywords : free-electron laser * soft X-rays * focusing * beam profile * ablation threshold * laser-matter interaction Subject RIV: BH - Optics, Masers, Lasers Impact factor: 3.709, year: 2007

  16. Efficient focusing of 8 keV X-rays with multilayer Fresnel zone plates fabricated by atomic layer deposition and focused ion beam milling

    International Nuclear Information System (INIS)

    Mayer, Marcel; Keskinbora, Kahraman; Grévent, Corinne; Szeghalmi, Adriana; Knez, Mato; Weigand, Markus; Snigirev, Anatoly; Snigireva, Irina; Schütz, Gisela

    2013-01-01

    The fabrication and performance of multilayer Al 2 O 3 /Ta 2 O 5 Fresnel zone plates in the hard X-ray range and a discussion of possible future developments considering available materials are reported. Fresnel zone plates (FZPs) recently showed significant improvement by focusing soft X-rays down to ∼10 nm. In contrast to soft X-rays, generally a very high aspect ratio FZP is needed for efficient focusing of hard X-rays. Therefore, FZPs had limited success in the hard X-ray range owing to difficulties of manufacturing high-aspect-ratio zone plates using conventional techniques. Here, employing a method of fabrication based on atomic layer deposition (ALD) and focused ion beam (FIB) milling, FZPs with very high aspect ratios were prepared. Such multilayer FZPs with outermost zone widths of 10 and 35 nm and aspect ratios of up to 243 were tested for their focusing properties at 8 keV and shown to focus hard X-rays efficiently. This success was enabled by the outstanding layer quality thanks to ALD. Via the use of FIB for slicing the multilayer structures, desired aspect ratios could be obtained by precisely controlling the thickness. Experimental diffraction efficiencies of multilayer FZPs fabricated via this combination reached up to 15.58% at 8 keV. In addition, scanning transmission X-ray microscopy experiments at 1.5 keV were carried out using one of the multilayer FZPs and resolved a 60 nm feature size. Finally, the prospective of different material combinations with various outermost zone widths at 8 and 17 keV is discussed in the light of the coupled wave theory and the thin-grating approximation. Al 2 O 3 /Ir is outlined as a promising future material candidate for extremely high resolution with a theoretical efficiency of more than 20% for as small an outermost zone width as 10 nm at 17 keV

  17. Studies for the development of a micro-focus monochromatic x-ray source with making use of a highly charged heavy ion beam

    International Nuclear Information System (INIS)

    Nakamura, Nobuyuki; Yoshiyasu, Nobuo; Nakayama, Ryo; Watanabe, Hirofumi

    2008-01-01

    We propose a new scheme for a micro-focus monochromatic X-ray source using a focused highly charged ion beam colliding with a solid surface. When highly charged ion approaches a surface, many electrons are captured into the ion and the so-called hollow atom is produced. The hollow atom will decay by emitting X-rays before and after hitting the surface. Such X-rays do not contain any contribution from bremsstrahlung, so that monochromatic X-rays can be obtained by using proper filters. For the first step of realizing the proposed scheme, an ion focusing system with a glass capillary has been developed. In order to study the monochromaticity of the emission, X-ray spectra from hollow atoms produced in the collisions between highly charged heavy ions and several surfaces have been observed. (author)

  18. Spot size characterization of focused non-Gaussian X-ray laser beams

    NARCIS (Netherlands)

    Chalupsky, J.; Krzywinski, J.; Juha, L.; Hajkova, V.; Cihelka, J.; Burian, T.; Vysin, L.; Gaudin, J.; Gleeson, A.; Jurek, M.; Khorsand, A. R.; Klinger, D.; Wabnitz, H.; Sobierajski, R.; Stormer, M.; Tiedtke, K.; Toleikis, S.

    2010-01-01

    We present a new technique for the characterization of non-Gaussian laser beams which cannot be described by an analytical formula. As a generalization of the beam spot area we apply and refine the definition of so called effective area (A(eff)) [1] in order to avoid using the full-width at half

  19. First observation of meridional focusing of an x-ray beam using diffraction by a crystal with a transverse groove

    Czech Academy of Sciences Publication Activity Database

    Hrdý, Jaromír; Franc, František; Artemiev, Nikolai; Hrdá, Jaromíra; Ziegler, E.; Bigault, Th.; Freud, A. K.

    2001-01-01

    Roč. 8, - (2001), s. 1203-1206 ISSN 0909-0495 R&D Projects: GA AV ČR IAA1010104; GA MPO PZ-CH/22 Institutional research plan: CEZ:AV0Z1010914 Keywords : x-ray beam Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.519, year: 2001

  20. Characterisation of edgeless technologies for pixellated and strip silicon detectors with a micro-focused X-ray beam

    Science.gov (United States)

    Bates, R.; Blue, A.; Christophersen, M.; Eklund, L.; Ely, S.; Fadeyev, V.; Gimenez, E.; Kachkanov, V.; Kalliopuska, J.; Macchiolo, A.; Maneuski, D.; Phlips, B. F.; Sadrozinski, H. F.-W.; Stewart, G.; Tartoni, N.; Zain, R. M.

    2013-01-01

    Reduced edge or ``edgeless'' detector design offers seamless tileability of sensors for a wide range of applications from particle physics to synchrotron and free election laser (FEL) facilities and medical imaging. Combined with through-silicon-via (TSV) technology, this would allow reduced material trackers for particle physics and an increase in the active area for synchrotron and FEL pixel detector systems. In order to quantify the performance of different edgeless fabrication methods, 2 edgeless detectors were characterized at the Diamond Light Source using an 11 μm FWHM 15 keV micro-focused X-ray beam. The devices under test were: a 150 μm thick silicon active edge pixel sensor fabricated at VTT and bump-bonded to a Medipix2 ROIC; and a 300 μm thick silicon strip sensor fabricated at CIS with edge reduction performed by SCIPP and the NRL and wire bonded to an ALiBaVa readout system. Sub-pixel resolution of the 55 μm active edge pixels was achieved. Further scans showed no drop in charge collection recorded between the centre and edge pixels, with a maximum deviation of 5% in charge collection between scanned edge pixels. Scans across the cleaved and standard guard ring edges of the strip detector also show no reduction in charge collection. These results indicate techniques such as the scribe, cleave and passivate (SCP) and active edge processes offer real potential for reduced edge, tiled sensors for imaging detection applications.

  1. Stress evaluation in thin films: Micro-focus synchrotron X-ray diffraction combined with focused ion beam patterning for d{sub o} evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Baimpas, Nikolaos, E-mail: nikolaos.baimpas@eng.ox.ac.uk [University of Oxford, Dept. of Engineering Science (United Kingdom); Le Bourhis, Eric [University of Poitiers, Institut P' , Laboratoire de Physique des Matériaux, Poitiers (France); Eve, Sophie [ENSICAEN, CRISMAT, Caen (France); Thiaudière, Dominique [Synchrotron SOLEIL, L' Orme des Merisiers Saint-Aubin, Paris (France); Hardie, Christopher [University of Oxford, Materials Department (United Kingdom); Korsunsky, Alexander M. [University of Oxford, Dept. of Engineering Science (United Kingdom)

    2013-12-31

    Nanocrystalline metallic coatings of sub-micron thickness are widely used in modern microelectronic applications. In X-ray diffraction experiments to determine both the residual and applied stresses in nanocrystalline coatings, one difficult challenge that comes up invariably is the determination of the strain-free lattice spacing d{sub o}. The present study addresses this challenge by using the focused ion beam (FIB) to generate a built-in strain-free reference by patterning (milling) a 50 × 50 μm{sup 2} region of the coating to produce an array of small stress-relieved “islands” ∼ 0.8 × 0.8 μm{sup 2} each. Transmission X-ray diffraction setup was used for data collection at DIFFABS beamline (Synchrotron SOLEIL, France). A 150 nm-thick multi-layered W–Cu nano-composite thin film on polyimide (Kapton®) substrate was studied. The samples were loaded incrementally using a compact uniaxial loading device, and micro-beam diffraction data were collected on and away from the reference array. It was shown experimentally that the “island” array remained approximately strain free throughout the experiment, providing an on-board d{sub o} lattice spacing reference. The changing lattice spacing d in the coating was also monitored away from the array, to deduce the elastic strain evolution during deformation. The results and their implications are presented and discussed. - Highlights: • In situ deformation study of laminate polycrystalline W–Cu thin films • Focused ion beam (FIB) patterning of an array of “islands” on thin films surface • X-ray diffraction on island-patterned region • Constant strain on “islands” independently of the deformation of the substrate.

  2. X-ray focusing using capillary arrays

    International Nuclear Information System (INIS)

    Nugent, K.A.; Chapman, H.N.

    1990-01-01

    A new form of X-ray focusing device based on glass capillary arrays is presented. Theoretical and experimental results for array of circular capillaries and theoretical and computational results for square hole capillaries are given. It is envisaged that devices such as these will find wide applications in X-ray optics as achromatic condensers and collimators. 3 refs., 4 figs

  3. Coherent hard x-ray focusing optics and applications

    Energy Technology Data Exchange (ETDEWEB)

    Yun, W.B.; Viccaro, P.J.; Chrzas, J.; Lai, B.

    1991-01-01

    Coherent hard x-ray beams with a flux exceeding 10{sup 9} photons/second with a bandwidth of 0.1% will be provided by the undulator at the third generation synchrotron radiation sources such as APS, ESRF, and Spring-8. The availability of such high flux coherent x-ray beams offers excellent opportunities for extending the coherence-based techniques developed in the visible and soft x-ray part of the electromagnetic spectrum to the hard x-rays. These x-ray techniques (e.g., diffraction limited microfocusing, holography, interferometry, phase contrast imaging and signal enhancement), may offer substantial advantages over non-coherence-based x-ray techniques currently used. For example, the signal enhancement technique may be used to enhance an anomalous x-ray or magnetic x-ray scattering signal by several orders of magnitude. Coherent x-rays can be focused to a very small (diffraction-limited) spot size, thus allowing high spatial resolution microprobes to be constructed. The paper will discuss the feasibility of the extension of some coherence-based techniques to the hard x-ray range and the significant progress that has been made in the development of diffraction-limited focusing optics. Specific experimental results for a transmission Fresnel phase zone plate that can focus 8.2 keV x-rays to a spot size of about 2 microns will be briefly discussed. The comparison of measured focusing efficiency of the zone plate with that calculated will be made. Some specific applications of zone plates as coherent x-ray optics will be discussed. 17 refs., 4 figs.

  4. Relativistic self-focusing of ultra-high intensity X-ray laser beams in warm quantum plasma with upward density profile

    International Nuclear Information System (INIS)

    Habibi, M.; Ghamari, F.

    2014-01-01

    The results of a numerical study of high-intensity X-ray laser beam interaction with warm quantum plasma (WQP) are presented. By means of an upward ramp density profile combined with quantum factors specially the Fermi velocity, we have demonstrated significant relativistic self-focusing (RSF) of a Gaussian electromagnetic beam in the WQP where the Fermi temperature term in the dielectric function is important. For this purpose, we have considered the quantum hydrodynamics model that modifies refractive index of inhomogeneous WQPs with the inclusion of quantum correction through the quantum statistical and diffraction effects in the relativistic regime. Also, to better illustration of the physical difference between warm and cold quantum plasmas and their effect on the RSF, we have derived the envelope equation governing the spot size of X-ray laser beam in Q-plasmas. In addition to the upward ramp density profile, we have found that the quantum effects would be caused much higher oscillation and better focusing of X-ray laser beam in the WQP compared to that of cold quantum case. Our computational results reveal the importance of the use of electrons density profile and Fermi speed in enhancing self-focusing of laser beam

  5. Studying signal collection in the punch-through protection area of a silicon micro-strip sensor using a micro-focused X-ray beam

    CERN Document Server

    Poley, Anne-luise; The ATLAS collaboration

    2018-01-01

    For the Phase-II Upgrade of the ATLAS detector, a new, all-silicon tracker will be constructed in order to cope with the increased track density and radiation level of the High-Luminosity Large Hadron Collider. While silicon strip sensors are designed to minimise the fraction of dead material and maximise the active area of a sensor, concessions must be made to the requirements of operating a sensor in a particle physics detector. Sensor geometry features like the punch-through protection deviate from the standard sensor architecture and thereby affect the charge collection in that area. In order to study the signal collection of silicon strip sensors over their punch-through-protection area, ATLAS silicon strip sensors were scanned with a micro-focused X-ray beam at the Diamond Light Source. Due to the highly focused X-ray beam ($\\unit[2\\times3]{\\upmu\\text{m}}^2$) and the short average path length of an electron after interaction with an X-ray photon ($\\unit[\\leq2]{\\upmu\\text{m}}$), local signal collection i...

  6. An x-ray technique for precision laser beam synchronization

    International Nuclear Information System (INIS)

    Landen, O.L.; Lerche, R.A.; Hay, R.G.; Hammel, B.A.; Kalantar, D.; Cable, M.D.

    1994-01-01

    A new x-ray technique for recording the relative arrival times of multiple laser beams at a common target with better than ± 10 ps accuracy has been implemented at the Nova laser facility. 100 ps, 3ω Nova beam are focused to separate locations on a gold ribbon target viewed from the side. The measurement consists of using well characterized re-entrant x-ray streak cameras for 1-dimensional streaked imaging of the > 3 keV x-rays emanating from these isolated laser plasmas. After making the necessary correction for the differential laser, x-ray and electron transit times involved, timing offsets as low as ± 7 ps are resolved, and on subsequent shots, corrected for, verified and independently checked. This level of synchronization proved critical in meeting the power balance requirements for indirectly-driven pulse-shaped Nova implosions

  7. Development of confocal micro X-ray fluorescence instrument using two X-ray beams

    International Nuclear Information System (INIS)

    Tsuji, Kouichi; Nakano, Kazuhiko; Ding Xunliang

    2007-01-01

    A new confocal micro X-ray fluorescence instrument was developed. This instrument has two independent micro X-ray tubes with Mo targets. A full polycapillary X-ray lens was attached to each X-ray tube. Another half polycapillary lens was attached to a silicon drift X-ray detector (SDD). The focal spots of the three lenses were adjusted to a common position. The effects of the excitation of two X-ray beams were investigated. The instrument enabled highly sensitive three-dimensional X-ray fluorescence analysis. We confirmed that the X-ray fluorescence intensity from the sample increased by applying the two independent X-ray tubes in confocal configuration. Elemental depth profiling of black wheat was demonstrated with the result that each element in the surface coat of a wheat grain showed unique distribution

  8. Soft X-ray focusing Telescope aboard AstroSat

    DEFF Research Database (Denmark)

    Singh, K. P.; Dewangan, G. C.; Chandra, S.

    2017-01-01

    The Soft X-ray focusing Telescope (SXT) is a moderateresolution X-ray imaging spectrometer supplementing the ultraviolet and hard X-ray payloads for broadband studies of cosmic sources with AstroSat. Well suited for observing bright X-ray sources, SXT observations of nearby active galactic nuclei...

  9. Beam line for experiments with coherent soft x-rays

    International Nuclear Information System (INIS)

    Howells, M.R.; Kirz, J.; Krinsky, S.

    1982-12-01

    The advantages of coherent soft x-rays for three-dimensional imaging of biological specimens are discussed, the x-ray source requirements are described, and the general design of the beam line and its optical system are given

  10. Performances of synchrotron radiation microbeam focused by monolithic half focusing polycapillary X-ray lens

    International Nuclear Information System (INIS)

    Sun Tianxi; Liu Zhiguo; He Bo; Wei Shiqiang; Xie Yaning; Liu Tao; Hu Tiandou; Ding Xunliang

    2007-01-01

    A monolithic half focusing polycapillary X-ray lens (MHFPXRL) composed of 289,000 capillaries is used to produce a synchrotron radiation microbeam. The energy dependence of the output focal distance, focal spot size, transmission efficiency, vertical beam position, and gain in flux density of this microbeam is studied in detail. There is a slight change in the output focal distance of the MHFPXRL when the X-ray energies change

  11. Stabilization of synchrotron radiation x-ray beam by MOSTAB

    CERN Document Server

    Kudo, T P; Tanida, H; Furukawa, Y; Hirono, T; Ishikawa, T; Nishino, Y

    2003-01-01

    Monochromator stabilization (MOSTAB) is a feedback control system to stabilize an x-ray beam of synchrotron radiation. It applies a feedback voltage to a piezo electric transducer attached to a double-crystal monochromator. We developed MOSTAB modules and examined their performances using SPring-8 beamlines. The x-ray beam position stabilization using MOSTAB was realized simultaneously with the x-ray beam intensity stabilization. As an example of its application, we performed EXAFS measurement with MOSTAB. (author)

  12. Full Multilayer Laue Lens for Focusing Hard X-rays

    International Nuclear Information System (INIS)

    Liu Chian; Shi, B.; Qian, J.; Conley, R.; Yan, H.; Wieczorek, M.; Macrander, A. T.; Maser, J.; Stephenson, G. B.

    2010-01-01

    Multilayer Laue Lenses (MLLs) were developed by us using dynamic diffraction effects to efficiently focus hard x-rays to very small spots. Using a partial MLL we were able to focus 19.5-keV hard x-rays to a line focus of 16 nm with an efficiency of 31%. A full MLL is a complete linear MLL structure. It can be fabricated by bonding two partial MLL wafers, or by growing the full structure using magnetron sputtering without bonding. A 40-μm full MLL, with a total of 5166 layers of WSi 2 and Si, has been successfully grown by sputter deposition. The layer thicknesses gradually vary from 4 nm to ∼400 nm and then back to 4 nm. Two coating runs were used to grow the full structure, one for each half. It took over 56 h for each run. A 100-μm nearly-full MLL was constructed by bonding. Each 50-μm half-structure has 1788 WSi 2 and Si layers with 12-nm to ∼32-nm thicknesses and ∼32-μm total thickness, followed by a thick WSi 2 layer of ∼17 μm, and an AuSn layer of ∼1 μm. Both full MLL structures survived dicing and polishing. The primary results demonstrate the feasibility and potential of a full MLL with a doubled numerical aperture and large beam acceptance for hard x-rays.

  13. Sagittal x-ray beam deviation at asymmetric inclined diffractors

    Czech Academy of Sciences Publication Activity Database

    Korytár, D.; Hrdý, Jaromír; Artemiev, Nikolai; Ferrari, C.; Freund, A.

    2001-01-01

    Roč. 8, - (2001), s. 1136-1139 ISSN 0909-0495 R&D Projects: GA MŠk OK 305; GA MPO PZ-CH/22 Institutional research plan: CEZ:AV0Z1010914 Keywords : x-ray optics * Si(111) W/grooved crystals * inclined diffraction * out-of-diffraction-plane beams * sagittal focusing Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.519, year: 2001

  14. Characterisation of strip silicon detectors for the ATLAS Phase-II Upgrade with a micro-focused X-ray beam

    CERN Document Server

    INSPIRE-00407830; Blue, Andrew; Bates, Richard; Bloch, Ingo; Diez, Sergio; Fernandez-Tejero, Javier; Fleta, Celeste; Gallop, Bruce; Greenall, Ashley; Gregor, Ingrid-Maria; Hara, Kazuhiko; Ikegami, Yoichi; Lacasta, Carlos; Lohwasser, Kristin; Maneuski, Dzmitry; Nagorski, Sebastian; Pape, Ian; Phillips, Peter W.; Sperlich, Dennis; Sawhney, Kawal; Soldevila, Urmila; Ullan, Miguel; Unno, Yoshinobu; Warren, Matt

    2016-07-29

    The planned HL-LHC (High Luminosity LHC) in 2025 is being designed to maximise the physics potential through a sizable increase in the luminosity, totalling 1x10^35 cm^-2 s^-1 after 10 years of operation. A consequence of this increased luminosity is the expected radiation damage at 3000 fb^-1, requiring the tracking detectors to withstand hadron equivalences to over 1x10^16 1 MeV neutrons per cm^2. With the addition of increased readout rates, a complete re-design of the current ATLAS Inner Detector (ID) is being developed as the Inner Tracker (ITk). Two proposed detectors for the ATLAS strip tracker region of the ITk were characterized at the Diamond Light Source with a 3 micron FWHM 15 keV micro focused X-ray beam. The devices under test were a 320 micron thick silicon stereo (Barrel) ATLAS12 strip mini sensor wire bonded to a 130 nm CMOS binary readout chip (ABC130) and a 320 micron thick full size radial (Endcap) strip sensor - utilizing bi-metal readout layers - wire bonded to 250 nm CMOS binary readout...

  15. Performances for confocal X-ray diffraction technology based on polycapillary slightly focusing X-ray optics

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Hehe; Liu, Zhiguo [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Sun, Tianxi, E-mail: stxbeijing@163.com [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Peng, Song [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Ma, Yongzhong [Center for Disease Control and Prevention of Beijing, Beijing 100013 (China); Sun, Weiyuan; Li, Yude; Lin, Xiaoyan; Zhao, Weigang; Zhao, Guangcui; Luo, Ping; Pan, Qiuli; Ding, Xunliang [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China)

    2013-09-21

    The confocal X-ray diffraction (XRD) technology based on a polycapillary slightly focusing X-ray lens (PSFXRL) in excitation channel and a polycapillary parallel X-ray lens (PPXRL) with a long input focal distance in detection channel was developed. The output focal spot of the PSFXRL and the input focal spot of the PPXRL were adjusted in confocal configuration, and only the X-rays from the volume overlapped by these foci could be accordingly detected. This confocal configuration was helpful in decreasing background. The convergence of the beam focused by the PSFXRL and divergence of the beam which could be collected by the PPXRL with a long input focal distance were both about 9 mrad at 8 keV. This was helpful in improving the resolution of lattice spacing of this confocal XRD technology. The gain in power density of such PSFXRL and PPXRL was about 120 and 7 at 11 keV, respectively, which was helpful in using the low power source to perform XRD analysis efficiently. The performances of this confocal XRD technology were provided, and some common plastics were analyzed. The experimental results demonstrated that the confocal diffraction technology base on polycapillary slightly focusing X-ray optics had wide potential applications.

  16. X-ray beam qualities for dental radiology purposes

    International Nuclear Information System (INIS)

    Santos, Marcus Aurelio P. dos; Fragoso, Maria da Conceicao de F.; Lima, Ricardo de A.; Hazim, Clovis A.

    2009-01-01

    In order to establish characteristics or properties of equipment for diagnostic radiology, e.g. ion chambers and semiconductor detectors, calibration laboratories offer a set of well-defined radiation conditions, called X-ray qualities, which can be used for many Physics studies and medical purposes. The standardization of radiation qualities has been carried out in several fields of study, but little attention has been given to the area of dental radiology, mainly for medical and physical applications using single-phase units with half-wave rectification. For this reason, a single-phase dental unit with adjustable peak voltage and tube current, called 'variable potential X-ray equipment', was developed aiming to define X-ray beam qualities for test and calibrations purposes. X-ray spectra at 50, 60 and 70 kVp were determined by using a CdTe detector and compared with those obtained for ten commercial X-ray dental units. As a result of this study, a set of X-ray qualities for the variable potential X-ray equipment was determined. The X-ray qualities spectra were utilized as reference for determination of a new set of X-ray qualities characterized for a constant potential X-ray equipment. Thus, sets of X-ray qualities were standardized and implemented in two X-ray laboratories: one with the variable potential X-ray equipment and other with constant potential X-ray equipment. These reference X-ray beam qualities should be used for test and calibration purposes involving scientific studies and services. (author)

  17. X-ray photoelectron microscope with a compact x-ray source generated by line-focused laser irradiation

    International Nuclear Information System (INIS)

    Yamaguchi, N.; Okamoto, Y.; Hara, T.; Takahashi, Z.; Nishimura, Y.; Sakata, A.; Watanabe, K.; Azuma, H.

    2004-01-01

    Full text: A laboratory-sized microscopic system of x-ray photoelectrons has been developing using a compact x-ray source produced by line-focused laser irradiation. The system is a scanning type photoelectron microscope where x-ray beam is micro-focused via a Schwartzschild optics. A compact laser-plasma x-ray source has been developed with a YAG laser system, a line-focus lens system, a tape-target driving system and a debris prevention system, that was operated at repetition rate of 10 Hz or 50 Hz. X-rays were delivered along line plasma whose length was 0.6 to 11 mm with higher intensity than that from a point-focused source. Because the transition line of Al V (13.1 nm) was prominent in the soft x-ray spectrum when the Al tape target irradiated at the lower power density of 10 11 W/cm 2 , the 13.1 nm x-ray was used as an excitation source. The Schwartzschild optics was set on the beamline at a distance about 1 m from the source, which was coated with Mo/Si multilayers for 13.1 nm x-ray. The designed demagnification is 224 that was confirmed in the previous experiment. Therefore, an x-ray micro spot of sub-micron size can be formed on a sample surface when the source size is less than about 0.2 mm. Samples were set on a two-axis high-precision piezo stage mounted to a four-axis manipulator. The electron energy analyzer was a spherical capacitor analyzer with mean diameter of 279.4 mm. The electron detector was a microchannel plate (MCP) with a phosphor screen and the optical image of electrons on the exit plane of the analyzer was taken and recorded by using an ultra low dark noise CCD camera, that was suited for detection of vast photoelectrons excited by x-ray pulse of ns-order duration. We performed spatial resolution test measurements by using a GaAs wafer coated with photo-resist that formed a stripe pattern. The spatial resolution less than 3 micron has been obtained from the variation of As 3d electron intensity along the position of the GaAs sample

  18. Scattered X-ray beam nondestructive testing

    International Nuclear Information System (INIS)

    Harding, G.; Kosanetzky, J.

    1988-01-01

    X-ray scatter interactions generally dominate the linear attenuation coefficient at the photon energies typical of medical and industrial radiography. Specific advantages of X-ray scatter imaging, including a flexible choice of measurement geometry, direct 3D-imaging capability (tomography) and improved information for material characterization, are illustrated with results from Compton and coherent scatter devices. Applications of a Compton backscatter scanner (ComScan) in the aerospace industry and coherent scatter imaging in security screening are briefly considered [pt

  19. Characterisation of silicon microstrip detectors for the ATLAS Phase-II Upgrade with a micro-focused X-ray beam

    International Nuclear Information System (INIS)

    Poley, Luise; Blue, Andrew; Bates, Richard

    2016-03-01

    The planned HL-LHC (High Luminosity LHC) in 2025 is being designed to maximise the physics potential through a sizable increase in the luminosity, totalling 1 x 10 35 cm -2 s -1 after 10 years of operation. A consequence of this increased luminosity is the expected radiation damage at 3000 fb -1 , requiring the tracking detectors to withstand hadron equivalences to over 1 x 10 16 1 MeV neutrons per cm 2 . With the addition of increased readout rates, a complete re-design of the current ATLAS Inner Detector (ID) is being developed as the Inner Tracker (ITk). Two proposed detectors for the ATLAS strip tracker region of the ITk were characterized at the Diamond Light Source with a 3 μm FWHM 15 keV micro focused X-ray beam. The devices under test were a 320 μm thick silicon stereo (Barrel) ATLAS12 strip mini sensor wire bonded to a 130 nm CMOS binary readout chip (ABC130) and a 320 μm thick full size radial (Endcap) strip sensor - utilizing bi-metal readout layers - wire bonded to 250 nm CMOS binary readout chips (ABCN-25). Sub-strip resolution of the 74.5 μm strips was achieved for both detectors. Investigation of the p-stop diffusion layers between strips is shown in detail for the wire bond pad regions. Inter strip charge collection measurements indicate that the effective width of the strip on the silicon sensors is determined by p-stops regions between the strips rather than the strip pitch. The collected signal allowed for the identification of operating thresholds for both devices, making it possible to compare signal response between different versions of silicon strip detector modules.

  20. Characterisation of strip silicon detectors for the ATLAS Phase-II Upgrade with a micro-focused X-ray beam

    Science.gov (United States)

    Poley, L.; Blue, A.; Bates, R.; Bloch, I.; Díez, S.; Fernandez-Tejero, J.; Fleta, C.; Gallop, B.; Greenall, A.; Gregor, I.-M.; Hara, K.; Ikegami, Y.; Lacasta, C.; Lohwasser, K.; Maneuski, D.; Nagorski, S.; Pape, I.; Phillips, P. W.; Sperlich, D.; Sawhney, K.; Soldevila, U.; Ullan, M.; Unno, Y.; Warren, M.

    2016-07-01

    The planned HL-LHC (High Luminosity LHC) in 2025 is being designed to maximise the physics potential through a sizable increase in the luminosity up to 6·1034 cm-2s-1. A consequence of this increased luminosity is the expected radiation damage at 3000 fb-1 after ten years of operation, requiring the tracking detectors to withstand fluences to over 1·1016 1 MeV neq/cm2. In order to cope with the consequent increased readout rates, a complete re-design of the current ATLAS Inner Detector (ID) is being developed as the Inner Tracker (ITk). Two proposed detectors for the ATLAS strip tracker region of the ITk were characterized at the Diamond Light Source with a 3 μm FWHM 15 keV micro focused X-ray beam. The devices under test were a 320 μm thick silicon stereo (Barrel) ATLAS12 strip mini sensor wire bonded to a 130 nm CMOS binary readout chip (ABC130) and a 320 μm thick full size radial (end-cap) strip sensor - utilizing bi-metal readout layers - wire bonded to 250 nm CMOS binary readout chips (ABCN-25). A resolution better than the inter strip pitch of the 74.5 μm strips was achieved for both detectors. The effect of the p-stop diffusion layers between strips was investigated in detail for the wire bond pad regions. Inter strip charge collection measurements indicate that the effective width of the strip on the silicon sensors is determined by p-stop regions between the strips rather than the strip pitch.

  1. Characterisation of silicon microstrip detectors for the ATLAS Phase-II Upgrade with a micro-focused X-ray beam

    Energy Technology Data Exchange (ETDEWEB)

    Poley, Luise [DESY, Hamburg (Germany); Blue, Andrew; Bates, Richard [Glasgow Univ. (United Kingdom). SUPA School of Physics and Astronomy; and others

    2016-03-15

    The planned HL-LHC (High Luminosity LHC) in 2025 is being designed to maximise the physics potential through a sizable increase in the luminosity, totalling 1 x 10{sup 35} cm{sup -2}s{sup -1} after 10 years of operation. A consequence of this increased luminosity is the expected radiation damage at 3000 fb{sup -1}, requiring the tracking detectors to withstand hadron equivalences to over 1 x 10{sup 16} 1 MeV neutrons per cm{sup 2}. With the addition of increased readout rates, a complete re-design of the current ATLAS Inner Detector (ID) is being developed as the Inner Tracker (ITk). Two proposed detectors for the ATLAS strip tracker region of the ITk were characterized at the Diamond Light Source with a 3 μm FWHM 15 keV micro focused X-ray beam. The devices under test were a 320 μm thick silicon stereo (Barrel) ATLAS12 strip mini sensor wire bonded to a 130 nm CMOS binary readout chip (ABC130) and a 320 μm thick full size radial (Endcap) strip sensor - utilizing bi-metal readout layers - wire bonded to 250 nm CMOS binary readout chips (ABCN-25). Sub-strip resolution of the 74.5 μm strips was achieved for both detectors. Investigation of the p-stop diffusion layers between strips is shown in detail for the wire bond pad regions. Inter strip charge collection measurements indicate that the effective width of the strip on the silicon sensors is determined by p-stops regions between the strips rather than the strip pitch. The collected signal allowed for the identification of operating thresholds for both devices, making it possible to compare signal response between different versions of silicon strip detector modules.

  2. Combined optic system based on polycapillary X-ray optics and single-bounce monocapillary optics for focusing X-rays from a conventional laboratory X-ray source

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Xuepeng; Liu, Zhiguo [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Sun, Tianxi, E-mail: stx@bnu.edu.cn [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Yi, Longtao; Sun, Weiyuan; Li, Fangzuo; Jiang, Bowen [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Ma, Yongzhong [Center for Disease Control and Prevention of Beijing, Beijing 100013 (China); Ding, Xunliang [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China)

    2015-12-01

    Two combined optic systems based on polycapillary X-ray optics and single-bounce monocapillary optics (SBMO) were designed for focusing the X-rays from a conventional laboratory X-ray source. One was based on a polycapillary focusing X-ray lens (PFXRL) and a single-bounce ellipsoidal capillary (SBEC), in which the output focal spot with the size of tens of micrometers of the PFXRL was used as the “virtual” X-ray source for the SBEC. The other system was based on a polycapillary parallel X-ray lens (PPXRL) and a single-bounce parabolic capillary (SBPC), in which the PPXRL transformed the divergent X-ray beam from an X-ray source into a quasi-parallel X-ray beam with the divergence of sever milliradians as the incident illumination of the SBPC. The experiment results showed that the combined optic systems based on PFXRL and SBEC with a Mo rotating anode X-ray generator with the focal spot with a diameter of 300 μm could obtain a focal spot with the total gain of 14,300 and focal spot size of 37.4 μm, and the combined optic systems based on PPXRL and SBPC with the same X-ray source mentioned above could acquire a focal spot with the total gain of 580 and focal spot size of 58.3 μm, respectively. The two combined optic systems have potential applications in micro X-ray diffraction, micro X-ray fluorescence, micro X-ray absorption near edge structure, full field X-ray microscopes and so on.

  3. Line focus x-ray tubes-a new concept to produce high brilliance x-rays.

    Science.gov (United States)

    Bartzsch, Stefan; Oelfke, Uwe

    2017-10-27

    Currently hard coherent x-ray radiation at high photon fluxes can only be produced with large and expensive radiation sources, such as 3[Formula: see text] generation synchrotrons. Especially in medicine, this limitation prevents various promising developments in imaging and therapy from being translated into clinical practice. Here we present a new concept of highly brilliant x-ray sources, line focus x-ray tubes (LFXTs), which may serve as a powerful and cheap alternative to synchrotrons and a range of other existing technologies. LFXTs employ an extremely thin focal spot and a rapidly rotating target for the electron beam which causes a change in the physical mechanism of target heating, allowing higher electron beam intensities at the focal spot. Monte Carlo simulations and numeric solutions of the heat equation are used to predict the characteristics of the LFXT. In terms of photon flux and coherence length, the performance of the line focus x-ray tube compares with inverse Compton scattering sources. Dose rates of up to 180 Gy [Formula: see text] can be reached in 50 cm distance from the focal spot. The results demonstrate that the line focus tube can serve as a powerful compact source for phase contrast imaging and microbeam radiation therapy. The production of a prototype seems technically feasible.

  4. Quantitative cone beam X-ray luminescence tomography/X-ray computed tomography imaging

    International Nuclear Information System (INIS)

    Chen, Dongmei; Zhu, Shouping; Chen, Xueli; Chao, Tiantian; Cao, Xu; Zhao, Fengjun; Huang, Liyu; Liang, Jimin

    2014-01-01

    X-ray luminescence tomography (XLT) is an imaging technology based on X-ray-excitable materials. The main purpose of this paper is to obtain quantitative luminescence concentration using the structural information of the X-ray computed tomography (XCT) in the hybrid cone beam XLT/XCT system. A multi-wavelength luminescence cone beam XLT method with the structural a priori information is presented to relieve the severe ill-posedness problem in the cone beam XLT. The nanophosphors and phantom experiments were undertaken to access the linear relationship of the system response. Then, an in vivo mouse experiment was conducted. The in vivo experimental results show that the recovered concentration error as low as 6.67% with the location error of 0.85 mm can be achieved. The results demonstrate that the proposed method can accurately recover the nanophosphor inclusion and realize the quantitative imaging

  5. Pulsed x-ray generation from a plasma focus device

    International Nuclear Information System (INIS)

    Zambra, M; Bruzzone, H; Sidelnikov, Y; Kies, W; Moreno, C; Sylvester, G; Silva, P; Moreno, J; Soto, L

    2003-01-01

    Dynamical pinches coupled to electrodes like the dense Z-pinch or the dense plasma focus have been intensively studied in the last four decades for their high fusion efficiency and their application potential. Though the expectations of the eighties of the last century, scaling these pinches up to fusion reactors, did not come true, the development of fast and powerful experiments resulted in new insights in pinch physics and paved the way for developing compact dynamical pinches as pulsed neutron and X-radiation sources for many applications. There is a permanent and growing interest in the research community for understanding and determining the generation properties of X-rays, neutrons and charged particles emitted from a high-temperature high-density plasmas, especially in the plasma focus configuration. The Plasma Physics and Plasma Technology Group of the CCHEN has developed the SPEED4 fast-plasma focus device, in collaboration with the Plasma Physics Group of the Dusseldorf University, in order to perform experimental studies such as X-ray and neutron emission, and electron and ion beam characterization (author)

  6. Cone-beam x-ray luminescence computed tomography based on x-ray absorption dosage

    Science.gov (United States)

    Liu, Tianshuai; Rong, Junyan; Gao, Peng; Zhang, Wenli; Liu, Wenlei; Zhang, Yuanke; Lu, Hongbing

    2018-02-01

    With the advances of x-ray excitable nanophosphors, x-ray luminescence computed tomography (XLCT) has become a promising hybrid imaging modality. In particular, a cone-beam XLCT (CB-XLCT) system has demonstrated its potential in in vivo imaging with the advantage of fast imaging speed over other XLCT systems. Currently, the imaging models of most XLCT systems assume that nanophosphors emit light based on the intensity distribution of x-ray within the object, not completely reflecting the nature of the x-ray excitation process. To improve the imaging quality of CB-XLCT, an imaging model that adopts an excitation model of nanophosphors based on x-ray absorption dosage is proposed in this study. To solve the ill-posed inverse problem, a reconstruction algorithm that combines the adaptive Tikhonov regularization method with the imaging model is implemented for CB-XLCT reconstruction. Numerical simulations and phantom experiments indicate that compared with the traditional forward model based on x-ray intensity, the proposed dose-based model could improve the image quality of CB-XLCT significantly in terms of target shape, localization accuracy, and image contrast. In addition, the proposed model behaves better in distinguishing closer targets, demonstrating its advantage in improving spatial resolution.

  7. Simulation of a dense plasma focus x-ray source

    International Nuclear Information System (INIS)

    Stark, R.A.

    1994-01-01

    The authors are performing simulations of the magnetohydrodynamics of a Dense Plasma Focus (DPF) x-ray source located at Science Research Laboratory (SRL), Alameda, CA, in order to optimize its performance. The SRL DPF, which was developed as a compact source for x-ray lithography, operates at 20 Hz, giving x-ray power (9--14 Angstroms) of 500 W using neon gas. The simulations are performed with the two dimensional MHD code MACH2, developed by Mission Research Corporation, with a steady state corona model as the equation of state. The results of studies of the sensitivity of x-ray output to charging voltage and current, and to initial gas density will be presented. These studies should indicate ways to optimize x-ray production efficiency. Simulations of various inner electrode configurations will also be presented

  8. Using refractive optics to broaden the focus of an X-ray mirror.

    Science.gov (United States)

    Laundy, David; Sawhney, Kawal; Dhamgaye, Vishal

    2017-07-01

    X-ray mirrors are widely used at synchrotron radiation sources for focusing X-rays into focal spots of size less than 1 µm. The ability of the beamline optics to change the size of this spot over a range up to tens of micrometres can be an advantage for many experiments such as X-ray microprobe and X-ray diffraction from micrometre-scale crystals. It is a requirement that the beam size change should be reproducible and it is often essential that the change should be rapid, for example taking less than 1 s, in order to allow high data collection rates at modern X-ray sources. In order to provide a controlled broadening of the focused spot of an X-ray mirror, a series of refractive optical elements have been fabricated and installed immediately before the mirror. By translation, a new refractive element is moved into the X-ray beam allowing a variation in the size of the focal spot in the focusing direction. Measurements using a set of prefabricated refractive structures with a test mirror showed that the focused beam size could be varied from less than 1 µm to over 10 µm for X-rays in the energy range 10-20 keV. As the optics is in-line with the X-ray beam, there is no effect on the centroid position of the focus. Accurate positioning of the refractive optics ensures reproducibility in the focused beam profile and no additional re-alignment of the optics is required.

  9. The histories of capillary optics for x-rays and ion beams in Russia, USA, and Japan

    International Nuclear Information System (INIS)

    Umezawa, Kenji

    2009-01-01

    This article introduces the history of X-ray lens and the present situation of ion beam focusing with glass capillaries systems. The basic technology of X-ray lens using glass capillaries was independently developed over 20 years by Prof. Kumakhov in the former Soviet Union and Dr. Soejima in Japan, respectively. In the 1990's, Prof. W.M. Gibson and his coworkers intensively studied X-rays and neutron optics in Albany, NY, USA. X-ray optics with glass capillaries, in these days is well known in the world. This unique technique was fabricated to collimate X-rays. Also, new ion beam analysis technique with glass capillaries systems has been intensively developed by Dr. Nebiki and Prof. Narusawa in Kochi, Japan. These X-rays and ion beams techniques have brought new application for many fields; X-ray detector, X-ray lithography, X-ray astronomy, microdiffraction, medical therapy and biological applications. (author)

  10. Development of a multi-lane X-ray mirror providing variable beam sizes

    Energy Technology Data Exchange (ETDEWEB)

    Laundy, D., E-mail: david.laundy@diamond.ac.uk; Sawhney, K.; Nistea, I.; Alcock, S. G.; Pape, I.; Sutter, J.; Alianelli, L.; Evans, G. [Diamond Light Source Ltd., Harwell Science and Innovation Campus, Didcot OX11 0DE (United Kingdom)

    2016-05-15

    Grazing incidence mirrors are used on most X-ray synchrotron beamlines to focus, collimate or suppress harmonics. Increasingly beamline users are demanding variable beam shapes and sizes at the sample position. We have now developed a new concept to rapidly vary the beam size and shape of a focused X-ray beam. The surface of an elliptically figured mirror is divided into a number of laterally separated lanes, each of which is given an additional longitudinal height profile calculated to shape the X-ray beam to a top-hat profile in the focal plane. We have now fabricated two prototype mirrors and present the results of metrology tests and measurements made with one of the mirrors focusing the X-rays on a synchrotron beamline. We envisage that such mirrors could be widely applied to rapid beam-size switching on many synchrotron beamlines.

  11. A submicron synchrotron X-ray beam generated by capillary optics

    International Nuclear Information System (INIS)

    Engstroem, P.; Larsson, S.; Rindby, A.; Buttkewitz, A.; Garbe, S.; Gaul, G.; Knoechel, A.; Lechtenberg, F.; Deutsches Elektronen-Synchrotron

    1991-01-01

    A novel capillary optics technique for focusing synchrotron X-ray beams has been applied in an experiment performed at the DORIS storage ring at HASYLAB. This new technqiue, which utilizes the total reflection properties of X-rays inside small capillaries, has recently been applied to generate microbeams of X-rays, with a beam size down to about 10 μm using conventional X-ray tubes. The result from our recent experiment shows that capillary optics can also be used to generate a submicron beam of X-rays from a synchrotron light source. A description of the capillary unit, and the alignment procedure is given. The influence of the thermal load on the device caused by the intense flux of synchrotron radiation will be discussed. Future perspectives of the capillary techniques as applied to synchrotron radiation will be discussed. (orig.)

  12. UHV photoelectron x-ray beam position monitor

    International Nuclear Information System (INIS)

    Johnson, E.D.; Oversluizen, T.

    1989-01-01

    As part of our research program to develop viable beam position monitors for both the X-ray and VUV beamlines at the NSLS, we have constructed vertical photon beam position monitors which are presently mounted in two front-ends in the X-ray ring. These area-type detectors are located before the safety shutters and are, therefore, able to monitor the beam position even during injection. The features of this type of monitor which contribute to its long-term stability, position sensitivity, and immunity to horizontal beam motion have been examined and will be discussed. 6 refs., 4 figs

  13. A new beamstop for microfocus X-ray capillary beams

    Energy Technology Data Exchange (ETDEWEB)

    Englich, Ulrich, E-mail: ue22@cornell.edu [Cornell University, Macromolecular Diffraction at CHESS (MacCHESS), Cornell High Energy Synchrotron Source, 200L Wilson Laboratory, Ithaca, NY 14853 (United States); Revesz, Peter [Cornell University, Cornell High Energy Synchrotron Source, Ithaca, NY 14853 (United States); Miller, William [Cornell University, Macromolecular Diffraction at CHESS (MacCHESS), Cornell High Energy Synchrotron Source, 200L Wilson Laboratory, Ithaca, NY 14853 (United States)

    2011-09-01

    In order to accurately measure the photon flux and to assist in aligning the beam, we have designed a modified beamstop device based on a photo diode integrated with the beamstop. The beamstop contains a small CdWO{sub 4} crystal that completely stops the X-rays and at the same time produces photoluminescence proportional to the X-ray flux. The light is then guided to a photosensitive diode using a flexible light pipe to monitor the flux. With this device we achieve the goal of stopping the primary X-ray beam and simultaneously monitoring the X-ray intensity, thus eliminating the need for integrating ion-chambers into the capillary or collimator mount.

  14. Bonded Multilayer Laue Lens for focusing hard X-rays

    International Nuclear Information System (INIS)

    Liu Chian; Conley, R.; Qian, J.; Kewish, C.M.; Macrander, A.T.; Maser, J.; Kang, H.C.; Yan, H.; Stephenson, G.B.

    2007-01-01

    We have fabricated partial Multilayer Laue Lens (MLL) linear zone plate structures with thousands of alternating WSi 2 and Si layers and various outermost zone widths according to the Fresnel zone plate formula. Using partial MLL structures, we were able to focus hard X-rays to line foci with a width of 30 nm and below. Here, we describe challenges and approaches used to bond these multilayers to achieve line and point focusing. Bonding was done by coating two multilayers with AuSn and heating in a vacuum oven at 280-300 o C. X-ray reflectivity measurements confirmed that there was no change in the multilayers after heating to 350 o C. A bonded MLL was polished to a 5-25 μm wedge without cracking. SEM image analyses found well-positioned multilayers after bonding. These results demonstrate the feasibility of a bonded full MLL for focusing hard X-rays

  15. Time correlation between plasma behaviour and soft x-ray emission in a plasma focus

    International Nuclear Information System (INIS)

    Hirano, Katsumi; Tagaya, Yutaka; Shimoda, Katsuji; Okabe, Yushiro; Yamamoto, Toshikazu

    1986-01-01

    Soft X-rays emitted from a plasma focus are investigated experimentally. In contrast to single-pulsive burst of neutron, hard X-rays, ion- and electron beams, the soft X-rays are observed from the collapse phase to the decay phase of the plasma column, and have typically three successive peaks in its signal. Each peak corresponds to the maximum compression, the disruption and the decay phase of plasma column. It is revealed that the first and the second peaks are radiated by plasma itself, whereas the third peak is caused by emission from the inner electrode face. (author)

  16. Advances in kilovoltage x-ray beam dosimetry

    Science.gov (United States)

    Hill, Robin; Healy, Brendan; Holloway, Lois; Kuncic, Zdenka; Thwaites, David; Baldock, Clive

    2014-03-01

    This topical review provides an up-to-date overview of the theoretical and practical aspects of therapeutic kilovoltage x-ray beam dosimetry. Kilovoltage x-ray beams have the property that the maximum dose occurs very close to the surface and thus, they are predominantly used in the treatment of skin cancers but also have applications for the treatment of other cancers. In addition, kilovoltage x-ray beams are used in intra operative units, within animal irradiators and in on-board imagers on linear accelerators and kilovoltage dosimetry is important in these applications as well. This review covers both reference and relative dosimetry of kilovoltage x-ray beams and provides recommendations for clinical measurements based on the literature to date. In particular, practical aspects for the selection of dosimeter and phantom material are reviewed to provide suitable advice for medical physicists. An overview is also presented of dosimeters other than ionization chambers which can be used for both relative and in vivo dosimetry. Finally, issues related to the treatment planning and the use of Monte Carlo codes for solving radiation transport problems in kilovoltage x-ray beams are presented.

  17. X-ray trace element analysis with positive ion beams

    International Nuclear Information System (INIS)

    Davis, R.H.

    1973-01-01

    A new trace element analysis having the advantage that many elements may be detected in a single measurement, based on positive charged particle induced X-ray florescence and on the production of X-rays by heavy ions, is described. Because of the large cross-sections for the production of discrete X-ray and the low yield of continuum radiation, positive charged particle X-ray florescence is a competitive, fast, analytic tool. In the experiment a beam of positive charged particles from an accelerator was directed toward a target. X-rays induced by the bombardment were detected by a Si(Li) detector the ouput from which was amplified and sorted in a multichannel analyzer. For rapid data handling and analysis, the multichannel analyzer or ADC unit was connected to an on-line computer. A large variety of targets prepared in collaboration with the oceanographers have been studied and spectra obtained for different particles having the same velocity are presented to show that the yield of discrete X-rays increases at least as rapidly as Z 2 . While protons of several MeV appear to be already competitive further advantage may be gained by heavy ions at lower energies since the continuum is reduced while the peak ''signals'' retain strength due to the Z 2 dependence. (S.B.)

  18. Anomalous x-ray radiation of beam plasma

    International Nuclear Information System (INIS)

    Dimitrov, S.K.; Zavyalov, M.A.; Mikhin, S.G.; Tarasenkov, V.A.; Telkovskij, V.G.; Khrabrov, V.A.

    1985-01-01

    The properties of non-equilibrium stationary plasma under the conditions of the planned plasma-chemical reactors based on beam-plasma discharge were investigated. The x-ray spectrum of the beam-plasma was measured and anomalous spectral properties were analyzed. Starting with some critical pressure the anomalous radiation was added to the classical bremsstrahlung spectrum. The occurrence of anomalous radiation can be used to diagnose the condition of beam transportation in such systems. (D.Gy.)

  19. Development of X-ray photoelectron microscope with a compact X-ray source generated by line-focused laser irradiation

    International Nuclear Information System (INIS)

    Yamaguchi, N.; Takahashi, Z.; Nishimura, Y.; Watanabe, K.; Okamoto, Y.; Sakata, A.; Azuma, H.; Hara, T.

    2005-01-01

    A laboratory-sized X-ray photoelectron microscope was constructed using a compact X-ray source produced by line-focused laser irradiation. The system is a scanning type photoelectron microscope where X-ray beam is micro-focused via Schwarzschild optics. A compact laser-plasma X-ray source has been developed with a YAG laser, a line-focus lens assembly, an Al tape-target driver and a debris prevention system. The 13.1 nm X-ray was delivered along line plasma whose length was 0.6 or 11 mm with higher intensity than that from a point-focused source. The Schwarzschild optics having the designed demagnification of 224, which was coated with Mo/Si multilayers for 13.1 nm X-ray, was set on the beamline 1 m distant from the source. The electron energy analyser was a spherical capacitor analyser with the photoelectron image detection system that was suited for detection of vast photoelectrons excited by an X-ray pulse of ns-order duration. The spatial resolution less than 5 μm has been confirmed from the variation of As 3d electron intensity along the position of the GaAs sample coated with a photo-resist test pattern

  20. Highly porous nanoberyllium for X-ray beam speckle suppression

    Energy Technology Data Exchange (ETDEWEB)

    Goikhman, Alexander, E-mail: agoikhman@ymail.com; Lyatun, Ivan; Ershov, Petr [Immanuel Kant Baltic Federal University, Nevskogo str. 14, Kaliningrad 236041 (Russian Federation); Snigireva, Irina [European Synchrotron Radiation Facility, BP 220, 38043 Grenoble (France); Wojda, Pawel [Immanuel Kant Baltic Federal University, Nevskogo str. 14, Kaliningrad 236041 (Russian Federation); Gdańsk University of Technology, 11/12 G. Narutowicza, Gdańsk 80-233 (Poland); Gorlevsky, Vladimir; Semenov, Alexander; Sheverdyaev, Maksim; Koletskiy, Viktor [A. A. Bochvar High-Technology Scientific Research Institute for Inorganic Materials, Rogova str. 5a, Moscow 123098 (Russian Federation); Snigirev, Anatoly [Immanuel Kant Baltic Federal University, Nevskogo str. 14, Kaliningrad 236041 (Russian Federation); European Synchrotron Radiation Facility, BP 220, 38043 Grenoble (France)

    2015-04-09

    A speckle suppression device containing highly porous nanoberyllium is proposed for manipulating the spatial coherence length and removing undesirable speckle structure during imaging experiments. This paper reports a special device called a ‘speckle suppressor’, which contains a highly porous nanoberyllium plate squeezed between two beryllium windows. The insertion of the speckle suppressor in an X-ray beam allows manipulation of the spatial coherence length, thus changing the effective source size and removing the undesirable speckle structure in X-ray imaging experiments almost without beam attenuation. The absorption of the nanoberyllium plate is below 1% for 1 mm thickness at 12 keV. The speckle suppressor was tested on the ID06 ESRF beamline with X-rays in the energy range from 9 to 15 keV. It was applied for the transformation of the phase–amplitude contrast to the pure amplitude contrast in full-field microscopy.

  1. Highly porous nanoberyllium for X-ray beam speckle suppression

    International Nuclear Information System (INIS)

    Goikhman, Alexander; Lyatun, Ivan; Ershov, Petr; Snigireva, Irina; Wojda, Pawel; Gorlevsky, Vladimir; Semenov, Alexander; Sheverdyaev, Maksim; Koletskiy, Viktor; Snigirev, Anatoly

    2015-01-01

    A speckle suppression device containing highly porous nanoberyllium is proposed for manipulating the spatial coherence length and removing undesirable speckle structure during imaging experiments. This paper reports a special device called a ‘speckle suppressor’, which contains a highly porous nanoberyllium plate squeezed between two beryllium windows. The insertion of the speckle suppressor in an X-ray beam allows manipulation of the spatial coherence length, thus changing the effective source size and removing the undesirable speckle structure in X-ray imaging experiments almost without beam attenuation. The absorption of the nanoberyllium plate is below 1% for 1 mm thickness at 12 keV. The speckle suppressor was tested on the ID06 ESRF beamline with X-rays in the energy range from 9 to 15 keV. It was applied for the transformation of the phase–amplitude contrast to the pure amplitude contrast in full-field microscopy

  2. X-Ray Powder Diffraction with Guinier - Haegg Focusing Cameras

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Allan

    1970-12-15

    The Guinier - Haegg focusing camera is discussed with reference to its use as an instrument for rapid phase analysis. An actual camera and the alignment procedure employed in its setting up are described. The results obtained with the instrument are compared with those obtained with Debye - Scherrer cameras and powder diffractometers. Exposure times of 15 - 30 minutes with compounds of simple structure are roughly one-sixth of those required for Debye - Scherrer patterns. Coupled with the lower background resulting from the use of a monochromatic X-ray beam, the shorter exposure time gives a ten-fold increase in sensitivity for the detection of minor phases as compared with the Debye - Scherrer camera. Attention is paid to the precautions taken to obtain reliable Bragg angles from Guinier - Haegg film measurements, with particular reference to calibration procedures. The evaluation of unit cell parameters from Guinier - Haegg data is discussed together with the application of tests for the presence of angle-dependent systematic errors. It is concluded that with proper calibration procedures and least squares treatment of the data, accuracies of the order of 0.005% are attainable. A compilation of diffraction data for a number of compounds examined in the Active Central Laboratory at Studsvik is presented to exemplify the scope of this type of powder camera.

  3. X-Ray Powder Diffraction with Guinier - Haegg Focusing Cameras

    International Nuclear Information System (INIS)

    Brown, Allan

    1970-12-01

    The Guinier - Haegg focusing camera is discussed with reference to its use as an instrument for rapid phase analysis. An actual camera and the alignment procedure employed in its setting up are described. The results obtained with the instrument are compared with those obtained with Debye - Scherrer cameras and powder diffractometers. Exposure times of 15 - 30 minutes with compounds of simple structure are roughly one-sixth of those required for Debye - Scherrer patterns. Coupled with the lower background resulting from the use of a monochromatic X-ray beam, the shorter exposure time gives a ten-fold increase in sensitivity for the detection of minor phases as compared with the Debye - Scherrer camera. Attention is paid to the precautions taken to obtain reliable Bragg angles from Guinier - Haegg film measurements, with particular reference to calibration procedures. The evaluation of unit cell parameters from Guinier - Haegg data is discussed together with the application of tests for the presence of angle-dependent systematic errors. It is concluded that with proper calibration procedures and least squares treatment of the data, accuracies of the order of 0.005% are attainable. A compilation of diffraction data for a number of compounds examined in the Active Central Laboratory at Studsvik is presented to exemplify the scope of this type of powder camera

  4. Hard X-ray nano-focusing with Montel mirror optics

    Energy Technology Data Exchange (ETDEWEB)

    Liu Wenjun, E-mail: wjliu@anl.gov [Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439 (United States); Ice, Gene E. [Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Assoufid, Lahsen; Liu Chian; Shi Bing; Zschack, Paul [Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439 (United States); Tischler, Jon [Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Qian Jun; Khachartryan, Ruben; Shu Deming [Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439 (United States)

    2011-09-01

    Kirkpatrick-Baez mirrors in the Montel (or nested) configuration were tested for hard X-ray nanoscale focusing at a third generation synchrotron beamline. In this scheme, two mirrors, mounted side-by-side and perpendicular to each other, provide for a more compact focusing system and a much higher demagnification and flux than the traditional sequential K-B mirror arrangement. They can accept up to a 120 {mu}mx120 {mu}m incident X-ray beam with a long working distance of 40 mm and broad-bandpass of energies up to {approx}30 keV. Initial test demonstrated a focal spot of about 150 nm in both horizontal and vertical directions with either polychromatic or monochromatic beam. Montel mirror optics is important and very appealing for achromatic X-ray nanoscale focusing in conventional non-extra-long synchrotron beamlines.

  5. Soft X-ray beam induced current technique

    Energy Technology Data Exchange (ETDEWEB)

    Watts, B; Ade, H [Department of Physics, North Carolina State University, Raleigh, NC 27695 (United States); Queen, D; Hellman, F [Department of Physics, University of California, Berkeley, CA 94720 (United States); Kilcoyne, A L D; Tyliszczak, T, E-mail: benjamin.watts@gmail.co [Advanced Light Source, Lawrence Berkeley Nat. Lab., Berkeley, CA 94720 (United States)

    2009-09-01

    Direct mapping of the charge transport efficiency of polymer solar cell devices using a soft X-ray beam induced current (SoXBIC) method is described. By fabricating a polymer solar cell on an x-ray transparent substrate, we demonstrate the ability to map polymer composition and nanoscale structure within an operating solar cell device and to simultaneously measure the local charge transport efficiency via the short-circuit current. A simple model is calculated and compared to experimental SoXBIC data of a PFB:F8BT bulk-heterojunction device in order to gain greater insight into the device operation and physics.

  6. Accelerators for E-beam and X-ray processing

    Energy Technology Data Exchange (ETDEWEB)

    Auslender, V.L. E-mail: auslen@inp.nsk.su; Bryazgin, A.A.; Faktorovich, B.L.; Gorbunov, V.A.; Kokin, E.N.; Korobeinikov, M.V.; Krainov, G.S.; Lukin, A.N.; Maximov, S.A.; Nekhaev, V.E.; Panfilov, A.D.; Radchenko, V.N.; Tkachenko, V.O.; Tuvik, A.A.; Voronin, L.A

    2002-03-01

    During last years the demand for pasteurization and desinsection of various food products (meat, chicken, sea products, vegetables, fruits, etc.) had increased. The treatment of these products in industrial scale requires the usage of powerful electron accelerators with energy 5-10 MeV and beam power at least 50 kW or more. The report describes the ILU accelerators with energy range up to 10 MeV and beam power up to 150 kW.The different irradiation schemes in electron beam and X-ray modes for various products are described. The design of the X-ray converter and 90 deg. beam bending system are also given.

  7. Hard X-ray emission spectroscopy with pink beam

    Energy Technology Data Exchange (ETDEWEB)

    Kvashnina, Kristina O.; Rossberg, Andre; Exner, Joerg; Scheinost, Andreas C. [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Molecular Structures

    2017-06-01

    Valence-band X-ray emission spectroscopy (XES) with a ''pink beam'', i.e. a beam with large energy bandwidth produced by a double-multilayer monochromator, is introduced here to overcome the weak count rate of monochromatic beams produced by conventional double-crystal monochromators. Our results demonstrate that - in spite of the large bandwidth in the order of 100 eV - the high spectral resolution of the Johann-type spectrometer is maintained, while the two orders of magnitude higher flux greatly reduces the required counting time. The short working distance Johann-type X-ray emission spectrometer and multilayer monochromator is available at ROBL.

  8. Advanced X-Ray Telescope Mirrors Provide Sharpest Focus Ever

    Science.gov (United States)

    1997-03-01

    Performing beyond expectations, the high- resolution mirrors for NASA's most powerful orbiting X-ray telescope have successfully completed initial testing at Marshall Space Flight Center's X-ray Calibration Facility, Huntsville, AL. "We have the first ground test images ever generated by the telescope's mirror assembly, and they are as good as -- or better than -- expected," said Dr. Martin Weisskopf, Marshall's chief scientist for NASA's Advanced X-ray Astrophysics Facility (AXAF). The mirror assembly, four pairs of precisely shaped and aligned cylindrical mirrors, will form the heart of NASA's third great observatory. The X-ray telescope produces an image by directing incoming X-rays to detectors at a focal point some 30 feet beyond the telescope's mirrors. The greater the percentage of X-rays brought to focus and the smaller the size of the focal spot, the sharper the image. Tests show that on orbit, the mirror assembly of the Advanced X-ray Astrophysics Facility will be able to focus approximately 70 percent of X-rays from a source to a spot less than one-half arc second in radius. The telescope's resolution is equivalent to being able to read the text of a newspaper from half a mile away. "The telescope's focus is very clear, very sharp," said Weisskopf. "It will be able to show us details of very distant sources that we know are out there, but haven't been able to see clearly." In comparison, previous X-ray telescopes -- Einstein and Rosat -- were only capable of focusing X- rays to five arc seconds. The Advanced X-ray Telescope's resolving power is ten times greater. "Images from the new telescope will allow us to make major advances toward understanding how exploding stars create and disperse many of the elements necessary for new solar systems and for life itself," said Dr. Harvey Tananbaum, director of the Advanced X- ray Astrophysics Facility Science Center at the Smithsonian Astrophysical Observatory, in Cambridge, MA -- responsible for the telescope

  9. Fabrication of nested elliptical KB mirrors using profile coating for synchrotron radiation X-ray focusing

    International Nuclear Information System (INIS)

    Liu Chian; Ice, G.E.; Liu, W.; Assoufid, L.; Qian, J.; Shi, B.; Khachatryan, R.; Wieczorek, M.; Zschack, P.; Tischler, J.Z.

    2012-01-01

    This paper describes fabrication methods used to demonstrate the advantages of nested or Montel optics for micro/nanofocusing of synchrotron X-ray beams. A standard Kirkpatrick-Baez (KB) mirror system uses two separated elliptical mirrors at glancing angles to the X-ray beam and sequentially arranged at 90° to each other to focus X-rays successively in the vertical and horizontal directions. A nested KB mirror system has the two mirrors positioned perpendicular and side-by-side to each other. Compared to a standard KB mirror system, Montel optics can focus a larger divergence and the mirrors can have a shorter focal length. As a result, nested mirrors can be fabricated with improved demagnification factor and ultimately smaller focal spot, than with a standard KB arrangement. The nested system is also more compact with an increased working distance, and is more stable, with reduced complexity of mirror stages. However, although Montel optics is commercially available for laboratory X-ray sources, due to technical difficulties they have not been used to microfocus synchrotron radiation X-rays, where ultra-precise mirror surfaces are essential. The main challenge in adapting nested optics for synchrotron microfocusing is to fabricate mirrors with a precise elliptical surface profile at the very edge where the two mirrors meet and where X-rays scatter. For example, in our application to achieve a sub-micron focus with high efficiency, a surface figure root-mean-square (rms) error on the order of 1 nm is required in the useable area along the X-ray footprint with a ∼0.1 mm-diameter cross section. In this paper we describe promising ways to fabricate precise nested KB mirrors using our profile coating technique and inexpensive flat Si substrates.

  10. A study of x-ray emission from the anode region in a plasma focus device

    International Nuclear Information System (INIS)

    Jia Wang; Tsinchi Yang

    1988-01-01

    The physical process of x-ray emission from the anode region in a plasma focus device due to the interaction of a powerful electron beam with the metal anode and with ionised metallic vapour from the anode is investigated. The influence of the magnetic field of the beam is taken into consideration. A MC-PIC model (Monte Carlo-particle in cell) is proposed for the process, in which an electron-photon collision cascade is simulated by the MC approach and the time-dependent state of metallic vapour is determined by PIC computation. The time-resolved energy spectra and angular distributions of x-ray emission from the extending anode region are calculated. The time-integrated characteristics of the x-ray emission can be compared with the results of experiments as far as they are available. (author)

  11. X-ray beam splitting design for concurrent imaging at hard X-ray FELs and synchrotron facilities

    Energy Technology Data Exchange (ETDEWEB)

    Oberta, P., E-mail: peter.oberta@rigaku.com [Institute of Physics, Academy of Sciences of the Czech Republic, v.v.i., Na Slovance 2, Praha 8, CZ-18221 (Czech Republic); Rigaku, Novodvorská 994, Praha 4, CZ-14221 (Czech Republic); Mokso, R. [Swiss Light Source, Paul Scherrer Institut, Villigen, CH-5232 Villigen (Switzerland)

    2013-11-21

    A new configuration of diffractive–refractive optics for beam splitting is investigated. The set-up can be applied to perform imaging with two beams simultaneously. It brings advantages toward dynamic studies using image guided diffraction or fluorescence spectroscopy. The optimal energy range of operation for the beam-splitter is between 7 keV and 24 keV, reaching best efficiency at an energy of 10 keV. Due to the long focusing distances (several tens of meters) created by the diffractive–refractive optics and the higher refraction efficiency in the softer energy range, the presented set-ups are ideal for hard X-ray FEL sources.

  12. Method for reducing x-ray background signals from insertion device x-ray beam position monitors

    Directory of Open Access Journals (Sweden)

    Glenn Decker

    1999-11-01

    Full Text Available A method is described that provides a solution to the long-standing problem of stray radiation-induced signals on photoemission-based x-ray beam position monitors (BPMs located on insertion device x-ray beam lines. The method involves the introduction of a chicane into the accelerator lattice that directs unwanted x radiation away from the photosensitive x-ray BPM blades. This technique has been implemented at the Advanced Photon Source, and experimental confirmation of the technique is provided.

  13. Beam dynamics simulation in the X-ray Compton source

    Energy Technology Data Exchange (ETDEWEB)

    Gladkikh, P.; Karnaukhov, I.; Telegin, Yu.; Shcherbakov, A. E-mail: shcherbakov@kipt.kharkov.ua; Zelinsky, A

    2002-05-01

    At the National Science Center 'Kharkov Institute of Physics and Technology' the X-ray source based on Compton scattering has been developed. The computer code for simulation of electron beam dynamics with taking into account the Compton scattering effect based on Monte Carlo method is described in this report. The first results of computer simulation of beam dynamics with electron-photon interaction, parameters of electron and photon beams are presented. Calculations were carried out with the lattice of synchrotron light source SRS-800 Ukrainian Synchrotron Center.

  14. Beam dynamics simulation in the X-ray Compton source

    International Nuclear Information System (INIS)

    Gladkikh, P.; Karnaukhov, I.; Telegin, Yu.; Shcherbakov, A.; Zelinsky, A.

    2002-01-01

    At the National Science Center 'Kharkov Institute of Physics and Technology' the X-ray source based on Compton scattering has been developed. The computer code for simulation of electron beam dynamics with taking into account the Compton scattering effect based on Monte Carlo method is described in this report. The first results of computer simulation of beam dynamics with electron-photon interaction, parameters of electron and photon beams are presented. Calculations were carried out with the lattice of synchrotron light source SRS-800 Ukrainian Synchrotron Center

  15. Beam dynamics simulation in the X-ray Compton source

    CERN Document Server

    Gladkikh, P; Telegin, Yu P; Shcherbakov, A; Zelinsky, A

    2002-01-01

    At the National Science Center 'Kharkov Institute of Physics and Technology' the X-ray source based on Compton scattering has been developed. The computer code for simulation of electron beam dynamics with taking into account the Compton scattering effect based on Monte Carlo method is described in this report. The first results of computer simulation of beam dynamics with electron-photon interaction, parameters of electron and photon beams are presented. Calculations were carried out with the lattice of synchrotron light source SRS-800 Ukrainian Synchrotron Center.

  16. Scintillator materials for x-ray detectors and beam monitors

    Czech Academy of Sciences Publication Activity Database

    Martin, T.; Koch, A.; Nikl, Martin

    2017-01-01

    Roč. 42, č. 6 (2017), s. 451-456 ISSN 0883-7694 R&D Projects: GA ČR GA16-15569S Institutional support: RVO:68378271 Keywords : scintillator * X-ray detector * beam monitor * synchrotron * thin film Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 5.199, year: 2016

  17. Broad beam X-rays attenuation in silicum glass

    International Nuclear Information System (INIS)

    Risticj, Dj.; Vukovicj, S.; Markovicj, P.

    1987-01-01

    Using broad beam geometry the attenuation for domestic silicum glass have been studied for constant X-ray potentials from 50 to 150 kV. The density of the silicium glass was 2,5x10 3 kg/m 3 . From the attenuation curves the half value layers were obtained. The use of this glass as the biological shield is pointed out. (author). 2 refs.; 2 tabs.; 2 figs

  18. Beam synchronous detection techniques for X-Ray spectroscopy

    International Nuclear Information System (INIS)

    Goujon, Gérard; Rogalev, Andreï; Goulon, José; Feite, Serge; Wilhelm, Fabrice

    2013-01-01

    The Photo diode detectors combine a set of properties that make them most appropriate, in particular, for X-ray Magnetic Circular Dichroism (XMCD) experiments. Under standard operating conditions, the detection bandwidth is primarily limited by the transimpedance preamplifier that converts the very low ac photocurrent into a voltage. On the other hand, when the photodiode is reverse biased, its finite shunt resistance will cause an undesirable, temperature dependent DC dark current. The best strategy to get rid of it is to use synchronous detection techniques. A classical implementation is based on the use of a chopper modulating the X-ray beam intensity at rather low frequencies (typically below 1 kHz). Here we report on the recent development of a fast Xray detection which has the capability to fully exploit the frequency structure of the ESRF X-ray beam (355 KHz and its harmonics). The availability of new wide band preamplifiers allowed us to extend the working frequency range up to a few MHz. A beam synchronous data processing was implemented in large FPGAs. Performances of the new detection system implemented at the ESRF beamline ID12 are illustrated with detection of the Fe K-edge XMCD spectra in garnets, using 4 bunches operation mode with modulation frequency of 1.4 MHz.

  19. Characterisation of microfocused beam for synchrotron powder diffraction using a new X-ray camera

    International Nuclear Information System (INIS)

    Thomas, C; Potter, J; Tang, C C; Lennie, A R

    2012-01-01

    The powder diffraction beamline I11, Diamond Light Source, is being continually upgraded as requirements of the user community evolve. Intensities of X-rays from the I11 in-vacuum electron undulator in the 3 GeV synchrotron fall off at higher energies. By focusing higher energy X-rays, we can overcome flux limitations, and open up new diffraction experiments. Here, we describe characterisation of microfocusing using compound refractive lenses (CRL). For a relatively modest outlay, we have developed an experimental setup and a novel X-ray camera with good sensitivity and a resolution specification suitable for characterising these focusing optics. We show that vertical oscillations in the focused beam compromise resolution of the source imaged by the CRL. Nevertheless, we have measured CRL focusing properties, and demonstrate the use of energy scanning to determine lens alignment. Real benefits of the intensity gain are illustrated.

  20. A new high-speed X-ray beam chopper

    International Nuclear Information System (INIS)

    McPherson, A.; Wang, J.; Lee, P. L.; Mills, D. M.

    1999-01-01

    A new high-speed x-ray beam chopper using laser scanner technology has been developed and tested on the SRI-CAT sector 1 beamline at the Advanced Photon Source (APS) storage ring (1). As illustrated in figure 1, it is compact in size and has two sets of transmission windows: BK-7 glass for visible light transmission and 0.23-mm-thick Be for the transmission of x-rays. The rotor is made of aluminum and has a diameter of 50.8 mm. A 0.5-mm-wide and 2.29-mm-tall slit is cut through the center of the rotor. The circumference of the rotor has a coating of 1-mm-thick Ni, which gives an attenuation of 10 8 at 30 keV. Turning at nearly 80000 RPM, this beam chopper has an opening time window of 2450 ns, corresponding to 67% of the revolution time of the APS storage ring. The primary feature in selecting laser scanner technology to develop into an x-ray beam chopper was the high level of rotational speed control of the rotor that makes up the beam chopper element (2). By using an optical feedback circuit to sample the rotational speed four times each revolution, the jitter in the position of the transmission open time window is only 3 ns at the 3 standard deviation level. The APS storage ring orbital frequency, supplied by the control room, is divided down to provide the appropriate drive frequency for the beam chopper motor controller. By this means, both the storage ring and the beam chopper are operating off the same master clock. After a turn-on time of about 15 to 20 seconds, the rotational precision of the motor results in immediate phase locking to the temporal structure of the APS storage ring. By inserting a Stanford delay generator between the frequency divider and the beam chopper motor controller, the phase between the storage ring temporal structure and the beam chopper rotation can be adjusted to position the transmission time window of the beam chopper on any desired part of the storage ring fill pattern. If an asymmetric fill pattern is used in the APS storage

  1. X-ray pencil beam facility for optics characterization

    Science.gov (United States)

    Krumrey, Michael; Cibik, Levent; Müller, Peter; Bavdaz, Marcos; Wille, Eric; Ackermann, Marcelo; Collon, Maximilien J.

    2010-07-01

    The Physikalisch-Technische Bundesanstalt (PTB) has used synchrotron radiation for the characterization of optics and detectors for astrophysical X-ray telescopes for more than 20 years. At a dedicated beamline at BESSY II, a monochromatic pencil beam is used by ESA and cosine Research since the end of 2005 for the characterization of novel silicon pore optics, currently under development for the International X-ray Observatory (IXO). At this beamline, a photon energy of 2.8 keV is selected by a Si channel-cut monochromator. Two apertures at distances of 12.2 m and 30.5 m from the dipole source form a pencil beam with a typical diameter of 100 μm and a divergence below 1". The optics to be investigated is placed in a vacuum chamber on a hexapod, the angular positioning is controlled by means of autocollimators to below 1". The reflected beam is registered at 5 m distance from the optics with a CCD-based camera system. This contribution presents design and performance of the upgrade of this beamline to cope with the updated design for IXO. The distance between optics and detector can now be 20 m. For double reflection from an X-ray Optical Unit (XOU) and incidence angles up to 1.4°, this corresponds to a vertical translation of the camera by 2 m. To achieve high reflectance at this angle even with uncoated silicon, a lower photon energy of 1 keV is available from a pair of W/B4C multilayers. For coated optics, a high energy option can provide a pencil beam of 7.6 keV radiation.

  2. White beam synchrotron x-ray topography of gallium arsenide

    International Nuclear Information System (INIS)

    Winter, J.M. Jr.; Green, R.E. Jr.; Corak, W.S.

    1988-01-01

    The defect structure of gallium arsenide was investigated using white beam transmission topography. The samples were cut and polished monocrystal substrates from different suppliers. The goal of the work was to determine the viability of the method for documenting various crystallographic defect structures and establishing their effect on the performance of integrated microwave circuits fabricated on the wafers. The principles of the technique, essentially identical to classical Laue x-ray diffraction, are outlined. Two distinct defect structures were determined in the topographs. Reasons for the defect structures were postulated and the application of the method for quality control assessments of manufacturer-supplied gallium arsenide substrates was assessed

  3. Target focusing configuration for X-ray laser experiments

    International Nuclear Information System (INIS)

    Seppala, L.G.

    1985-01-01

    X-ray laser experiments imposed a new demand on the Novette focusing optics. These optics had to provide highly uniform, double-sided illumination on a target region 1.0 cm long by 100 to 200 μm wide. This line focus requirement had to be achieved without degrading the diagnostic reflection from the last surface of the focus lens and without potential ghost focus problems. The only optical configuration that preserves the diagnostic reflection is shown. A negative focal length cylinder lens is placed between the focus lens and the debris shield, with the concave surface facing toward the focus lens. Any ghost reflections from the cylinder lens or debris shield are degraded by astigmatism, making them less hazardous. In practice, the uniformity of illumination is probably about the same for a positive or a negative cylinder lens. The minimum Novette focused spot was approximately 50 to 75 μm in diameter, and the fabrication errors in the 80-cm-diam precision cylinder lens produced a line focus 25 μm wide. a negative cylinder lens design was chosen, however, to optimize the illumination uniformity in the case of line widths of several hundred microns

  4. X-ray emission as a diagnostic from pseudospark-sourced electron beams

    Energy Technology Data Exchange (ETDEWEB)

    Bowes, D., E-mail: david.bowes@strath.ac.uk [Department of Physics, SUPA, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Yin, H.; He, W.; Zhang, L.; Cross, A.W.; Ronald, K.; Phelps, A.D.R. [Department of Physics, SUPA, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Chen, D.; Zhang, P. [Computed Tomography Lab, School of Mathematical Sciences, Capital Normal University, Beijing 100048 (China); Chen, X.; Li, D. [Department of Electronic Engineering, Queen Mary University of London, London E1 4NS (United Kingdom)

    2014-09-15

    X-ray emission has been achieved using an electron beam generated by a pseudospark low-pressure discharge and utilised as a diagnostic for beam detection. A 300 A, 34 kV PS-sourced electron beam pulse of 3 mm diameter impacting on a 0.1 mm-thick molybdenum target generated X-rays which were detected via the use of a small, portable X-ray detector. Clear X-ray images of a micro-sized object were captured using an X-ray photodetector. This demonstrates the inducement of proton induced X-ray emission (PIXE) not only as an indicator of beam presence but also as a future X-ray source for small-spot X-ray imaging of materials.

  5. Homogenious focusing with a transient soft X-ray laser for irradiation experiments

    Czech Academy of Sciences Publication Activity Database

    Kazamias, S.; Cassou, K.; Guilbaud, O.; Klisnick, A.; Ros, D.; Plé, F.; Jamelot, G.; Rus, Bedřich; Kozlová, Michaela; Stupka, Michal; Mocek, Tomáš; Douillet, D.; Zeitoun, P.; Joyeux, D.; Phalippou, D.

    2006-01-01

    Roč. 263, - (2006), s. 98-104 ISSN 0030-4018 R&D Projects: GA MŠk(CZ) LC528; GA ČR GA202/05/2316 Institutional research plan: CEZ:AV0Z10100523 Keywords : soft X-Ray laser * focusing * laser plasma * UV radiation * beam profile Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.480, year: 2006

  6. Development of X-ray and ion diagnostic methods for plasma focus research

    International Nuclear Information System (INIS)

    Sadowski, M.

    1986-12-01

    A review of experimental methods used for investigation of X-rays and ion-beams emmited from plasma focus facilities is presented. The research program has been realized at the Institute for Nuclear Studies in Swierk and at the Institut fuer Plasmaforschung in Stuttgart, within the frames of an international co-operation. The studies on ion emission from different PF facilities are reviewed. The application of CN-films with Al-filters and of different ion-pinhole cameras is described. The use of a Thomson mass-spectrometer adopted for plasma studies is presented. The time-resolved measurements combined with a simultaneous mass- and energy-analysis of the ion beams are also described. The most important results of these studies are summarized. Particular attention is also paid to the studies of the X-ray emission. The use of stereoscopic sets of vacuum pinhole cameras with thin Be-filters is described. The application of X-ray pinhole cameras equipped with miniature scintillators for time-resolved measurements is also presented. The most important results of the X-ray emission studies are summarized. 35 refs., 12 figs. (author)

  7. Upgrading multilayer zone plate technology for hard x-ray focusing

    Energy Technology Data Exchange (ETDEWEB)

    Hirotomo, Toshiki; Konishi, Shigeki [Graduate School of Material Science, University of Hyogo, Kamigori, Hyogo 678-1297 (Japan); SPring-8 Service Co., Ltd (Japan); Takano, Hidekazu, E-mail: htakano@sci.u-hyogo.ac.jp; Sumida, Kazuhiro; Tsusaka, Yoshiyuki; Kagoshima, Yasushi [Graduate School of Material Science, University of Hyogo, Kamigori, Hyogo 678-1297 (Japan); Koyama, Takahisa [Graduate School of Material Science, University of Hyogo, Kamigori, Hyogo 678-1297 (Japan); Japan Synchrotron Radiation Research Institute (JASRI/SPring-8) (Japan); Ichimaru, Satoshi; Ohchi, Tadayuki [NTT Advanced Technology Corporation (Japan); Takenaka, Hisataka [NTT Advanced Technology Corporation (Japan); TOYAMA Corporation (Japan)

    2016-01-28

    Multilayer zone plate (MZP) technology for hard X-ray focusing was upgraded and its focusing performance was evaluated using 20-keV X-rays at the synchrotron beamline (BL24XU) of SPring-8. The MZP consists of MoSi{sub 2} and Si layers alternately deposited on a glass fiber by magnetron sputtering so that all zone boundaries satisfy the Fresnel zone configuration. The focused beam was evaluated using knife-edge scanning in which the measured intensity distribution is identical to the line spread function (LSF) in the focal plane. The focused beamsize of about 30 nm was estimated by oscillation peaks observed in the measured LSF according to Rayleigh’s criterion.

  8. Spectral structure of a polycapillary lens shaped X-ray beam

    Science.gov (United States)

    Gogolev, A. S.; Filatov, N. A.; Uglov, S. R.; Hampai, D.; Dabagov, S. B.

    2018-04-01

    Polycapillary X-ray optics is widely used in X-ray analysis techniques to create a small secondary source, for instance, or to deliver X-rays to the point of interest with minimum intensity losses [1]. The main characteristics of the analytical devices on its base are the size and divergence of the focused or translated beam. In this work, we used the photon-counting pixel detector ModuPIX to study the parameters for polycapillary focused X-ray tube radiation as well as the energy and spatial dependences of radiation at the focus. We have characterized the high-speed spectral camera ModuPIX, which is a single Timepix device with a fast parallel readout allowing up to 850 frames per second with 256 × 256 pixels and a 55 μm pitch defined by the frame frequency. By means of the silicon monochromator the energy response function is measured in clustering mode by the energy scan over total X-ray tube spectrum.

  9. Measurement of X-ray beam emittance using crystal optics at an X-ray undulator beamline

    International Nuclear Information System (INIS)

    Kohmura, Yoshiki; Suzuki, Yoshio; Awaji, Mitsuhiro; Tanaka, Takashi; Hara, Toru; Goto, Shunji; Ishikawa, Tetsuya

    2000-01-01

    We present a method of using crystal optics to measure the emittance of the X-ray source. Two perfect crystals set in (++) configuration work as a high-resolution collimator. The phase-space diagram (i.e. beam cross-section and angular distribution) could be determined without any assumptions on the light source. When the measurement is done at short wavelength radiation from undulator, the electron beam emittance is larger than the diffraction limit of the X-rays. Therefore, the electron beam emittance could be estimated. The measurement was done with the hard X-rays of 18.5 and 55 keV from an undulator beamline, BL 47XU, of SPring-8. The horizontal emittance of the X-ray beam was estimated to be about 7.6 nmrad, close to the designed electron beam emittance of the storage ring (7 nmrad). Some portions of the instrumental functions, such as the scattering by filters and windows along the beamline and the slight bent of the crystal planes of the monochromator, could not be precisely evaluated, but an upper limit for the vertical emittance of the electron beam could be obtained as 0.14 nmrad

  10. Nuclear Malaysia Plasma Focus Device as a X-ray Source For Radiography Applications

    International Nuclear Information System (INIS)

    Rokiah Mohd Sabri; Abdul Halim Baijan; Siti Aiasah Hashim; Mohd Rizal Mohd Chulan; Wah, L.K.; Mukhlis Mokhtar; Azaman Ahmad; Rosli Che Ros

    2013-01-01

    A 3.375 kJ plasma focus is designed to operate at 13.5 kV for the purpose of studying x-ray source for radiography in Argon discharge. X-rays is detected by using x-ray film from the mammography radiographic plate. The feasibility of the plasma focus as a high intensity flash x-ray source for good contrast in radiography image is presented. (author)

  11. Errors in dual x-ray beam differential absorptiometry

    International Nuclear Information System (INIS)

    Bolin, F.; Preuss, L.; Gilbert, K.; Bugenis, C.

    1977-01-01

    Errors pertinent to the dual beam absorptiometry system have been studied and five areas are given in detail: (1) scattering, in which a computer analysis of multiple scattering shows little error due to this effect; (2) geometrical configuration effects, in which the slope of the sample is shown to influence the accuracy of the measurement; (3) Poisson variations, wherein it is shown that a simultaneous reduction can be obtained in both dosage and statistical error; (4) absorption coefficients, in which the effect of variation in absorption coefficient compilations is shown to have a critical effect on the interpretations of experimental data; and (5) filtering, wherein is shown the need for filters on dual beam systems using a characteristic x-ray output. A zero filter system is outlined

  12. Measurement of X-ray beam emittance using crystal optics at an X-ray undulator beamline

    CERN Document Server

    Kohmura, Y; Awaji, M; Tanaka, T; Hara, T; Goto, S; Ishikawa, T

    2000-01-01

    We present a method of using crystal optics to measure the emittance of the X-ray source. Two perfect crystals set in (++) configuration work as a high-resolution collimator. The phase-space diagram (i.e. beam cross-section and angular distribution) could be determined without any assumptions on the light source. When the measurement is done at short wavelength radiation from undulator, the electron beam emittance is larger than the diffraction limit of the X-rays. Therefore, the electron beam emittance could be estimated. The measurement was done with the hard X-rays of 18.5 and 55 keV from an undulator beamline, BL 47XU, of SPring-8. The horizontal emittance of the X-ray beam was estimated to be about 7.6 nmrad, close to the designed electron beam emittance of the storage ring (7 nmrad). Some portions of the instrumental functions, such as the scattering by filters and windows along the beamline and the slight bent of the crystal planes of the monochromator, could not be precisely evaluated, but an upper li...

  13. Focusing polycapillary to reduce parasitic scattering for inelastic x-ray measurements at high pressure

    International Nuclear Information System (INIS)

    Chow, P.; Xiao, Y. M.; Rod, E.; Bai, L. G.; Shen, G. Y.; Sinogeikin, S.; Gao, N.; Ding, Y.; Mao, H.-K.

    2015-01-01

    The double-differential scattering cross-section for the inelastic scattering of x-ray photons from electrons is typically orders of magnitude smaller than that of elastic scattering. With samples 10-100 μm size in a diamond anvil cell at high pressure, the inelastic x-ray scattering signals from samples are obscured by scattering from the cell gasket and diamonds. One major experimental challenge is to measure a clean inelastic signal from the sample in a diamond anvil cell. Among the many strategies for doing this, we have used a focusing polycapillary as a post-sample optic, which allows essentially only scattered photons within its input field of view to be refocused and transmitted to the backscattering energy analyzer of the spectrometer. We describe the modified inelastic x-ray spectrometer and its alignment. With a focused incident beam which matches the sample size and the field of view of polycapillary, at relatively large scattering angles, the polycapillary effectively reduces parasitic scattering from the diamond anvil cell gasket and diamonds. Raw data collected from the helium exciton measured by x-ray inelastic scattering at high pressure using the polycapillary method are compared with those using conventional post-sample slit collimation

  14. Short-wavelength soft-x-ray laser pumped in double-pulse single-beam non-normal incidence

    International Nuclear Information System (INIS)

    Zimmer, D.; Ros, D.; Guilbaud, O.; Habib, J.; Kazamias, S.; Zielbauer, B.; Bagnoud, V.; Ecker, B.; Aurand, B.; Kuehl, T.; Hochhaus, D. C.; Neumayer, P.

    2010-01-01

    We demonstrated a 7.36 nm Ni-like samarium soft-x-ray laser, pumped by 36 J of a neodymium:glass chirped-pulse amplification laser. Double-pulse single-beam non-normal-incidence pumping was applied for efficient soft-x-ray laser generation. In this case, the applied technique included a single-optic focusing geometry for large beam diameters, a single-pass grating compressor, traveling-wave tuning capability, and an optimized high-energy laser double pulse. This scheme has the potential for even shorter-wavelength soft-x-ray laser pumping.

  15. Experimental characterization of X-ray transverse coherence in the presence of beam transport optics

    DEFF Research Database (Denmark)

    Chubar, O.; Fluerasu, A.; Chu, Y.S.

    2013-01-01

    A simple Boron fiber based interference scheme [1] and other similar schemes are currently routinely used for X-ray coherence estimation at 3rd generation synchrotron radiation sources. If such a scheme is applied after a perfect monochromator and without any focusing / transport optics...... in the optical path, the interpretation of the measured interference pattern is relatively straightforward and can be done in terms of the basic parameters of the source [2]. However, if the interference scheme is used after some focusing optics, e.g. close to the X-ray beam waist, the visibility of fringes can...... be significantly affected by the new shape of the focused beam phase-space. At the same time, optical element imperfections still have a negative impact on the transverse coherence. In such situations, which are frequently encountered in experiments at beamlines, the quantitative interpretation of a measured...

  16. Hard X-ray dosimetry of a plasma focus suitable for industrial radiography

    Science.gov (United States)

    Knoblauch, P.; Raspa, V.; Di Lorenzo, F.; Clausse, A.; Moreno, C.

    2018-04-01

    Dosimetric measurements of the hard X-ray emission by a small-chamber 4.7 kJ Mather-type plasma focus device capable of producing neat radiographs of metallic objects, were carried out with a set of thermoluminescent detectors TLD 700 (LiF:Mg,Ti). Measurements of the hard X-ray dose dependence with the angular position relative to the electrodes axis, are presented. The source-detector distance was changed in the range from 50 to 100 cm, and the angular positions were explored between ± 70°, relative to the symmetry axis of the electrodes. On-axis measurements show that the X-ray intensity is uniform within a half aperture angle of 6°, in which the source delivers an average dose of (1.5 ± 0.1) mGy/sr per shot. Monte Carlo calculations suggest that the energy of the electron beam responsible for the X-ray emission ranges 100-600 keV.

  17. X-ray focusing with Wolter microchannel plate optics

    CERN Document Server

    Price, G J; Beijersbergen, M W; Fraser, G W; Bavdaz, M; Boutot, J P; Fairbend, R; Flyckt, S O; Peacock, A; Tomaselli, E

    2002-01-01

    Square-pore microchannel plate (MCP) X-ray optics of the 'lobster-eye' geometry have frequently been described in the literature. We have now investigated the use of a radial channel packing geometry which, in the context of an MCP pair slumped to the correct radii of curvature, can form a conic approximation to the Wolter Type I grazing incidence X-ray optic. Such an optic can provide a large effective area with very low mass and may be ideally suited for use in applications such as planetary imaging X-ray fluorescence. We present here the results of X-ray illumination of the first such optic, fabricated by Photonis SAS, France.

  18. Constancy check of beam quality in conventional diagnostic X-ray equipment

    International Nuclear Information System (INIS)

    Costa, Alessandro M.; Badin, Romulo S.; Leite, Marina S.; Caldas, Linda V.E.

    2008-01-01

    A tandem ionization chamber was developed for quality control programs of X-ray equipment used in conventional radiography and mammography. A methodology for the use of the tandem chamber in the constancy check of diagnostic X-ray beam qualities was established. The application at a medical X-ray imaging facility of this established methodology is presented. The use of the tandem chamber in the constancy check of diagnostic X-ray beam qualities is a useful method to control the performance of the X-ray equipment

  19. X-ray beam monitor made by thin-film CVD single-crystal diamond.

    Science.gov (United States)

    Marinelli, Marco; Milani, E; Prestopino, G; Verona, C; Verona-Rinati, G; Angelone, M; Pillon, M; Kachkanov, V; Tartoni, N; Benetti, M; Cannatà, D; Di Pietrantonio, F

    2012-11-01

    A novel beam position monitor, operated at zero bias voltage, based on high-quality chemical-vapor-deposition single-crystal Schottky diamond for use under intense synchrotron X-ray beams was fabricated and tested. The total thickness of the diamond thin-film beam monitor is about 60 µm. The diamond beam monitor was inserted in the B16 beamline of the Diamond Light Source synchrotron in Harwell (UK). The device was characterized under monochromatic high-flux X-ray beams from 6 to 20 keV and a micro-focused 10 keV beam with a spot size of approximately 2 µm × 3 µm square. Time response, linearity and position sensitivity were investigated. Device response uniformity was measured by a raster scan of the diamond surface with the micro-focused beam. Transmissivity and spectral responsivity versus beam energy were also measured, showing excellent performance of the new thin-film single-crystal diamond beam monitor.

  20. X-ray-ultraviolet beam splitters for the Michelson interferometer

    International Nuclear Information System (INIS)

    Delmotte, Franck; Ravet, Marie-Francoise; Bridou, Francoise; Varniere, Francoise; Zeitoun, Philippe; Hubert, Sebastien; Vanbostal, Laurent; Soullie, Gerard

    2002-01-01

    With the aim of realizing a Michelson interferometer working at 13.9 nm, we have developed a symmetrical beam splitter with multilayers deposited on the front and back sides of a silicon nitride membrane. On the basis of the experimental optical properties of the membrane, simulations have been performed to define the multilayer structure that provides the highest reflectivity-transmission product. Optimized Mo-Si multilayers have been successfully deposited on both sides of the membrane by use of the ion-beam sputtering technique, with a thickness-period reproducibility of 0.1 nm. Measurements by means of synchrotron radiation at 13.9 nm and at an angle of 45 deg. provide a reflectivity of 14.2% and a transmission of 15.2% for a 60% s-polarized light, close to the simulated values. Such a beam splitter has been used for x-ray laser Michelson interferometry at 13.9 nm. The first interferogram is discussed

  1. X-ray-ultraviolet beam splitters for the Michelson interferometer.

    Science.gov (United States)

    Delmotte, Franck; Ravet, Marie-Françoise; Bridou, Françoise; Varnière, Françoise; Zeitoun, Philippe; Hubert, Sébastien; Vanbostal, Laurent; Soullie, Gérard

    2002-10-01

    With the aim of realizing a Michelson interferometer working at 13.9 nm, we have developed a symmetrical beam splitter with multilayers deposited on the front and back sides of a silicon nitride membrane. On the basis of the experimental optical properties of the membrane, simulations have been performed to define the multilayer structure that provides the highest reflectivity-transmission product. Optimized Mo-Si multilayers have been successfully deposited on both sides of t he membrane by use of the ion-beam sputtering technique, with a thickness-period reproducibility of 0.1 nm. Measurements by means of synchrotron radiation at 13.9 nm and at an angle of 45 degrees provide a reflectivity of 14.2% and a transmission of 15.2% for a 60% s-polarized light, close to the simulated values. Such a beam splitter has been used for x-ray laser Michelson interferometry at 13.9 nm. The first interferogram is discussed.

  2. PBFA II lithium beam characterization from inner-shell x-ray images

    International Nuclear Information System (INIS)

    Moats, A.R.; Derzon, M.S.; Chandler, G.A.; Dukart, R.J.; Haill, T.A.

    1994-01-01

    The Particle Beam Fusion Accelerator (PBFA II) is not driving targets with ICF-relevant lithium ion beams. During the most recent lithium beam target series, time-integrated x-ray pinhole cameras viewed the ion-induced inner-shell x-ray fluorescence from the central gold cone target and a titanium-coated strip. Ion beam profiles at a nominal 10 mm radius and fixed azimuthal direction were obtained from images of the Ti K α , fluorescence of a Ti-coated Al diagnostic wire. The gold cone gave us beam profiles at a nominal 3 mm radius and at all azimuthal angles from the Au L α fluorescence. From these profiles, we obtained the ion beam vertical focus position, full-width-at-half-maximum, and the degree of azimuthal uniformity for the lithium target shots. For these initial results, beam steering problems were evident. Azimuthal uniformity was measured from the ion beam footprint on the outer Au case (predominantly Au L α ) of the hohlraum target and were found to be in the same range (up to 30%) as for previous proton beam target series. We then present plans for Li beam diagnostics for an upcoming target experimental series

  3. Functional characterization of planar sensors with active edges using laser and X-ray beam scans

    International Nuclear Information System (INIS)

    Povoli, M.; Bagolini, A.; Boscardin, M.; Dalla Betta, G.-F.; Giacomini, G.; Hasi, J.; Oh, A.; Zorzi, N.

    2013-01-01

    We report on the functional characterization of planar sensors with active edges fabricated at Fondazione Bruno Kessler (FBK), Trento, Italy. The measurements here reported were performed by means of laser and X-ray beam scans mainly focusing on the signal efficiency of the edge region of the devices. Results are very encouraging and show very good sensitivity up to few microns away from the device physical edge

  4. Functional characterization of planar sensors with active edges using laser and X-ray beam scans

    Energy Technology Data Exchange (ETDEWEB)

    Povoli, M., E-mail: povoli@disi.unitn.it [Dipartimento di Ingegneria e Scienza dell' Informazione, Università di Trento, Via Sommarive, 14, I-38123 Povo di Trento (Italy); INFN, Sezione di Padova (Gruppo Collegato di Trento),Via Sommarive, 14, I-38123 Povo di Trento (Italy); Bagolini, A.; Boscardin, M. [Fondazione Bruno Kessler, Centro per i Materiali e i Microsistemi (FBK-CMM), Via Sommarive, 18, I-38123 Povo di Trento (Italy); Dalla Betta, G.-F. [Dipartimento di Ingegneria e Scienza dell' Informazione, Università di Trento, Via Sommarive, 14, I-38123 Povo di Trento (Italy); INFN, Sezione di Padova (Gruppo Collegato di Trento),Via Sommarive, 14, I-38123 Povo di Trento (Italy); Giacomini, G. [Fondazione Bruno Kessler, Centro per i Materiali e i Microsistemi (FBK-CMM), Via Sommarive, 18, I-38123 Povo di Trento (Italy); Hasi, J. [SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025-7015 (United States); Oh, A. [The University of Manchester, Oxford Road, Manchester M13 9PL (United Kingdom); Zorzi, N. [Fondazione Bruno Kessler, Centro per i Materiali e i Microsistemi (FBK-CMM), Via Sommarive, 18, I-38123 Povo di Trento (Italy)

    2013-08-01

    We report on the functional characterization of planar sensors with active edges fabricated at Fondazione Bruno Kessler (FBK), Trento, Italy. The measurements here reported were performed by means of laser and X-ray beam scans mainly focusing on the signal efficiency of the edge region of the devices. Results are very encouraging and show very good sensitivity up to few microns away from the device physical edge.

  5. CRL X-ray tube

    International Nuclear Information System (INIS)

    Kolchevsky, N.N.; Petrov, P.V.

    2015-01-01

    A novel types of X-ray tubes with refractive lenses are proposed. CRL-R X-ray tube consists of Compound Refractive Lens- CRL and Reflection X-ray tube. CRL acts as X-ray window. CRL-T X-ray consists of CRL and Transmission X-ray tube. CRL acts as target for electron beam. CRL refractive lens acts as filter, collimator, waveguide and focusing lens. Properties and construction of the CRL X-ray tube are discussed. (authors)

  6. New X-ray beam position monitors with submicron resolution utilizing imaging of scattered X-rays at CHESS

    International Nuclear Information System (INIS)

    Revesz, Peter; Temnykh, Alexander B.; Pauling, Alan K.

    2011-01-01

    At CHESS' A, F and G wiggler beam lines three new video beam position monitors (VBPMs) have been commissioned. These new VBPMs utilize X-rays scattered from the graphite filter (A and F line) or from a beryllium window (G-line) as the white wiggler beam passes through them. As the X-rays scatter in all directions from the scattering medium, a slit camera creates an image of the beam's footprint on a fluorescent screen. This image is then viewed by a CCD camera and analyzed using a computer program to calculate the intensity centroid, the beam profile and integrated intensity. These data are delivered to the CHESS signal archiving system for storage and display. The new systems employ digital cameras. These cameras are free of the noise inherent to the analog systems with long video signal connections. As a result, the beam position data delivered by the new systems are more reliable and accurate as shown by beam position traces using different beam position monitors on the same beam line.

  7. New X-ray beam position monitors with submicron resolution utilizing imaging of scattered X-rays at CHESS

    Energy Technology Data Exchange (ETDEWEB)

    Revesz, Peter, E-mail: pr20@cornell.edu [Cornell University, Cornell High Energy Synchrotron Source, Ithaca 14850, NY (United States); Temnykh, Alexander B. [Cornell University, Laboratory for Elem-Particle Physics, Ithaca 14850, NY (United States); Pauling, Alan K. [Cornell University, Cornell High Energy Synchrotron Source, Ithaca 14850, NY (United States)

    2011-09-01

    At CHESS' A, F and G wiggler beam lines three new video beam position monitors (VBPMs) have been commissioned. These new VBPMs utilize X-rays scattered from the graphite filter (A and F line) or from a beryllium window (G-line) as the white wiggler beam passes through them. As the X-rays scatter in all directions from the scattering medium, a slit camera creates an image of the beam's footprint on a fluorescent screen. This image is then viewed by a CCD camera and analyzed using a computer program to calculate the intensity centroid, the beam profile and integrated intensity. These data are delivered to the CHESS signal archiving system for storage and display. The new systems employ digital cameras. These cameras are free of the noise inherent to the analog systems with long video signal connections. As a result, the beam position data delivered by the new systems are more reliable and accurate as shown by beam position traces using different beam position monitors on the same beam line.

  8. Focusing properties of x-ray polymer refractive lenses from SU-8 resist layer

    Science.gov (United States)

    Snigirev, Anatoly A.; Snigireva, Irina; Drakopoulos, Michael; Nazmov, Vladimir; Reznikova, Elena; Kuznetsov, Sergey; Grigoriev, Maxim; Mohr, Jurgen; Saile, Volker

    2003-12-01

    Compound refractive lenses printed in Al and Be are becoming the key X-ray focusing and imaging components of beamline optical layouts at the 3rd generation synchrotron radiation sources. Recently proposed planar optical elements based on Si, diamond etc. may substantially broaden the spectrum of the refractive optics applicability. Planar optics has focal distances ranging from millimeters to tens of meters offering nano- and micro-focusing lenses, as well as beam condensers and collimators. Here we promote deep X-ray lithography and LIGA-type techniques to create high aspect-ratio lens structures for different optical geometries. Planar X-ray refractive lenses were manufactured in 1 mm thick SU-8 negative resist layer by means of deep synchrotron radiation lithography. The focusing properties of lenses were studied at ID18F and BM5 beamlines at the ESRF using monochromatic radiation in the energy range of 10 - 25 keV. By optimizing lens layout, mask making and resist processing, lenses of good quality were fabricated. The resolution of about 270 nm (FWHM) with gain in the order of 300 was measured at 14 keV. In-line holography of B-fiber was realized in imaging and projection mode with a magnification of 3 and 20, respectively. Submicron features of the fiber were clearly resolved. A radiation stability test proved that the fabricated lenses don't change focusing characteristics after dose of absorbed X-ray radiation of about 2 MJ/cm3. The unique radiation stability along with the high effficiency of SU8 lenses opens wide range of their synchrotron radiation applications such as microfocusing elements, condensers and collimators.

  9. The quality of high-energy X-ray beams

    International Nuclear Information System (INIS)

    LaRiviere, P.D.

    1989-01-01

    Supplement 17 of the British Journal of Radiology is a survey of central-axis depth doses for radiotherapy machines, patterned largely on BJR Supplement 11 (1972). Inspection of high-energy X-ray depth doses for a 10 x 10 cm field at an SSD of 100 cm disclosed large differences between the two sets of data, especially for qualities above 8 MV, e.g. a depth dose of 80% at 10 cm is rated at about 19 MV according to BJR Supplement 11, and 23 MV according to BJR Supplement 17. It was found that Supplement 17 depth-dose data above 8 MV were erratic, but Supplement 11 data could be represented by an analytical expression, providing a unique means of assigning MV quality. It was also found that dose-weighted average energy of the filtered beam plotted smoothly against depth dose. For dosimetric purposes, it is suggested that this parameter be used as a true measure of beam quality, removing discrepancies introduced by the use of nominal MV for this purpose. (author)

  10. Working gas effects on the X-ray emission of a plasma focus device

    Energy Technology Data Exchange (ETDEWEB)

    Cengher, M; Presura, R; Zoita, V [Inst. of Physics and Technology of Radiation Devices, Bucharest (Romania)

    1997-12-31

    Experiments on the plasma focus device IPF-2/20 operating with argon, neon and mixtures of argon with deuterium were performed and some X-ray emission parameters measured. The time evolution of the X-ray emission and dependence of the X-ray yield on the working gas composition was analyzed. The softer X radiation was measured with time resolution in the energy bands from 4 to 40 keV, and the hard X-rays for energies above 200 keV. In deuterium-argon mixtures the soft X-ray yield increases both with pressure (for the same ratio of argon) and with the quantity of argon added to deuterium at the same total pressure. For argon or neon the hard X-ray yield is lower than for deuterium-heavy gas mixtures. The softer X-ray yield decreases with pressure both for neon and for argon. (author). 4 figs., 5 refs.

  11. Computed tomography for light materials using a monochromatic X-ray beam produced by parametric X-ray radiation

    Energy Technology Data Exchange (ETDEWEB)

    Hayakawa, Y., E-mail: yahayak@lebra.nihon-u.ac.jp [Laboratory for Electron Beam Research and Application, Nihon University, Narashinodai 7-24-1, Funabashi 274-8501 (Japan); Hayakawa, K.; Inagaki, M. [Laboratory for Electron Beam Research and Application, Nihon University, Narashinodai 7-24-1, Funabashi 274-8501 (Japan); Kaneda, T. [Nihon University School of Dentistry at Matsudo, Sakaecho-Nishi 2-870-1, Matsudo 271-8587 (Japan); Nakao, K.; Nogami, K. [Laboratory for Electron Beam Research and Application, Nihon University, Narashinodai 7-24-1, Funabashi 274-8501 (Japan); Sakae, T. [Nihon University School of Dentistry at Matsudo, Sakaecho-Nishi 2-870-1, Matsudo 271-8587 (Japan); Sakai, T.; Sato, I. [Laboratory for Electron Beam Research and Application, Nihon University, Narashinodai 7-24-1, Funabashi 274-8501 (Japan); Takahashi, Y. [Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), Oho, Tsukuba 305-8501 (Japan); Tanaka, T. [Laboratory for Electron Beam Research and Application, Nihon University, Narashinodai 7-24-1, Funabashi 274-8501 (Japan)

    2013-08-15

    Computed tomography (CT) for light materials such as soft biological tissues was performed using a monochromatic X-ray beam provided by a parametric X-ray radiation (PXR) source at the Laboratory for Electron Beam Research and Application (LEBRA) of Nihon University. Using a high-efficiency flat panel detector (FPD), each projection image for CT was taken with exposure times of 5 or 10 s, and 60–360 projection images in each run were obtained with total measurement time of 5 min to 1 h. CT images were obtained from the projection images using the conventional calculation method. The typical tomograms obtained had sharp outlines, which are likely attributable to the propagation-based phase contrast.

  12. On the response of electronic personal dosimeters in constant potential and pulsed X-ray beams

    Energy Technology Data Exchange (ETDEWEB)

    Guimaraes, Margarete C.; Silva, Teogenes; Silva, Claudete R.E., E-mail: margaretecristinag@gmail.com [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Oliveira, Paulo Marcio C. de [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Anatomia e Imagem

    2015-07-01

    Electronic personal dosimeters (EPDs) based on solid state detectors have widely been used but some deficiencies in their response in pulsed radiation beams have been reported. Nowadays, there is not an international standard for pulsed X-ray beams for calibration or type testing of dosimeters. Irradiation conditions for testing the response of EPDs in both the constant potential and pulsed X-ray beams were established in CDTN. Three different types of EPDs were tested in different conditions in similar ISO and IEC X-ray qualities. Results stressed the need of performing additional checks before using EPDs in constant potential or pulsed X-rays. (author)

  13. Structure in defocused beams of x-ray mirrors: causes and possible solutions

    Science.gov (United States)

    Sutter, John P.; Alcock, Simon G.; Rust, Fiona; Wang, Hongchang; Sawhney, Kawal

    2014-09-01

    Grazing incidence mirrors are now a standard optic for focusing X-ray beams. Both bimorph and mechanically bendable mirrors are widely used at Diamond Light Source because they permit a wide choice of focal lengths. They can also be deliberately set out of focus to enlarge the X-ray beam, and indeed many beamline teams now wish to generate uniform beam spots of variable size. However, progress has been slowed by the appearance of fine structure in these defocused beams. Measurements showing the relationship between the medium-frequency polishing error and this structure over a variety of beam sizes will be presented. A theoretical model for the simulations of defocused beams from general mirrors will then be developed. Not only the figure error and its first derivative the slope error, but also the second derivative, the curvature error, must be considered. In conclusion, possible ways to reduce the defocused beam structure by varying the actuators' configuration and settings will be discussed.

  14. Nanoscale radiation transport and clinical beam modeling for gold nanoparticle dose enhanced radiotherapy (GNPT) using X-rays.

    Science.gov (United States)

    Zygmanski, Piotr; Sajo, Erno

    2016-01-01

    We review radiation transport and clinical beam modelling for gold nanoparticle dose-enhanced radiotherapy using X-rays. We focus on the nanoscale radiation transport and its relation to macroscopic dosimetry for monoenergetic and clinical beams. Among other aspects, we discuss Monte Carlo and deterministic methods and their applications to predicting dose enhancement using various metrics.

  15. Neutron and X-ray emission studies in a low energy plasma focus

    Energy Technology Data Exchange (ETDEWEB)

    Zakaullah, M. [Quaid-i-Azam Univ., Islamabad (Pakistan). Dept. of Physics; Murtaza, G. [Quaid-i-Azam Univ., Islamabad (Pakistan). Dept. of Physics; Qamar, S. [Quaid-i-Azam Univ., Islamabad (Pakistan). Dept. of Physics; Ahmad, I. [Quaid-i-Azam Univ., Islamabad (Pakistan). Dept. of Physics; Beg, M.M. [Quaid-i-Azam Univ., Islamabad (Pakistan). Dept. of Physics

    1996-03-01

    In a low energy Mather-type plasma focus energized by a single 32 {mu}F capacitor, the X-ray and neutron emission is investigated using time-integrated and time-resolved detectors. The X-ray emission profile has a width (FWHM) of 40-50 ns. The neutron emission profile is broader compared to the X-ray emission profile and also delayed by 30-40 ns. To identify different regimes of X-ray emission, an X-ray pin-hole camera along with different absorption filters is employed. While the X-ray emission is high within a narrow pressure range of 2.0-2.5 mbar, the neutron emission is intense for a wider range of 1.0-4.5 mbar. The intense X-ray emission seems to originate from the axially moving shock wave. These results also indicate rather different production mechanisms for X-ray and neutron emission. Also on comparing the X-ray images with Al(2 {mu}m), Al(5 {mu}m), Al(9 {mu}m) filters, we find that the bulk of X-rays from the focus filament have energies less than 2 keV. (orig.).

  16. Partially coherent X-ray wavefront propagation simulations including grazing-incidence focusing optics.

    Science.gov (United States)

    Canestrari, Niccolo; Chubar, Oleg; Reininger, Ruben

    2014-09-01

    X-ray beamlines in modern synchrotron radiation sources make extensive use of grazing-incidence reflective optics, in particular Kirkpatrick-Baez elliptical mirror systems. These systems can focus the incoming X-rays down to nanometer-scale spot sizes while maintaining relatively large acceptance apertures and high flux in the focused radiation spots. In low-emittance storage rings and in free-electron lasers such systems are used with partially or even nearly fully coherent X-ray beams and often target diffraction-limited resolution. Therefore, their accurate simulation and modeling has to be performed within the framework of wave optics. Here the implementation and benchmarking of a wave-optics method for the simulation of grazing-incidence mirrors based on the local stationary-phase approximation or, in other words, the local propagation of the radiation electric field along geometrical rays, is described. The proposed method is CPU-efficient and fully compatible with the numerical methods of Fourier optics. It has been implemented in the Synchrotron Radiation Workshop (SRW) computer code and extensively tested against the geometrical ray-tracing code SHADOW. The test simulations have been performed for cases without and with diffraction at mirror apertures, including cases where the grazing-incidence mirrors can be hardly approximated by ideal lenses. Good agreement between the SRW and SHADOW simulation results is observed in the cases without diffraction. The differences between the simulation results obtained by the two codes in diffraction-dominated cases for illumination with fully or partially coherent radiation are analyzed and interpreted. The application of the new method for the simulation of wavefront propagation through a high-resolution X-ray microspectroscopy beamline at the National Synchrotron Light Source II (Brookhaven National Laboratory, USA) is demonstrated.

  17. Energy dispersive detector for white beam synchrotron x-ray fluorescence imaging

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Matthew D., E-mail: Matt.Wilson@stfc.ac.uk; Seller, Paul; Veale, Matthew C. [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Campus,UK (United Kingdom); Connolley, Thomas [Diamond Light Source, I12 Beamline, Harwell Campus, Didcot, Oxfordshire (United Kingdom); Dolbnya, Igor P.; Malandain, Andrew; Sawhney, Kawal [Diamond Light Source, B16 Beamline, Harwell Campus, Didcot, Oxfordshire (United Kingdom); Grant, Patrick S.; Liotti, Enzo; Lui, Andrew [Department of Materials, University of Oxford Parks Road, Oxford (United Kingdom)

    2016-07-27

    A novel, “single-shot” fluorescence imaging technique has been demonstrated on the B16 beamline at the Diamond Light Source synchrotron using the HEXITEC energy dispersive imaging detector. A custom made furnace with 200µm thick metal alloy samples was positioned in a white X-ray beam with a hole made in the furnace walls to allow the transmitted beam to be imaged with a conventional X-ray imaging camera consisting of a 500 µm thick single crystal LYSO scintillator, mirror and lens coupled to an AVT Manta G125B CCD sensor. The samples were positioned 45° to the incident beam to enable simultaneous transmission and fluorescence imaging. The HEXITEC detector was positioned at 90° to the sample with a 50 µm pinhole 13 cm from the sample and the detector positioned 2.3m from pinhole. The geometric magnification provided a field of view of 1.1×1.1mm{sup 2} with one of the 80×80 pixels imaging an area equivalent to 13µm{sup 2}. Al-Cu alloys doped with Zr, Ag and Mo were imaged in transmission and fluorescence mode. The fluorescence images showed that the dopant metals could be simultaneously imaged with sufficient counts on all 80x80 pixels within 60 s, with the X-ray flux limiting the fluorescence imaging rate. This technique demonstrated that it is possible to simultaneously image and identify multiple elements on a spatial resolution scale ~10µm or higher without the time consuming need to scan monochromatic energies or raster scan a focused beam of X-rays. Moving to high flux beamlines and using an array of detectors could improve the imaging speed of the technique with element specific imaging estimated to be on a 1 s timescale.

  18. Energy dispersive detector for white beam synchrotron x-ray fluorescence imaging

    International Nuclear Information System (INIS)

    Wilson, Matthew D.; Seller, Paul; Veale, Matthew C.; Connolley, Thomas; Dolbnya, Igor P.; Malandain, Andrew; Sawhney, Kawal; Grant, Patrick S.; Liotti, Enzo; Lui, Andrew

    2016-01-01

    A novel, “single-shot” fluorescence imaging technique has been demonstrated on the B16 beamline at the Diamond Light Source synchrotron using the HEXITEC energy dispersive imaging detector. A custom made furnace with 200µm thick metal alloy samples was positioned in a white X-ray beam with a hole made in the furnace walls to allow the transmitted beam to be imaged with a conventional X-ray imaging camera consisting of a 500 µm thick single crystal LYSO scintillator, mirror and lens coupled to an AVT Manta G125B CCD sensor. The samples were positioned 45° to the incident beam to enable simultaneous transmission and fluorescence imaging. The HEXITEC detector was positioned at 90° to the sample with a 50 µm pinhole 13 cm from the sample and the detector positioned 2.3m from pinhole. The geometric magnification provided a field of view of 1.1×1.1mm"2 with one of the 80×80 pixels imaging an area equivalent to 13µm"2. Al-Cu alloys doped with Zr, Ag and Mo were imaged in transmission and fluorescence mode. The fluorescence images showed that the dopant metals could be simultaneously imaged with sufficient counts on all 80x80 pixels within 60 s, with the X-ray flux limiting the fluorescence imaging rate. This technique demonstrated that it is possible to simultaneously image and identify multiple elements on a spatial resolution scale ~10µm or higher without the time consuming need to scan monochromatic energies or raster scan a focused beam of X-rays. Moving to high flux beamlines and using an array of detectors could improve the imaging speed of the technique with element specific imaging estimated to be on a 1 s timescale.

  19. Large-aperture focusing of x rays with micropore optics using dry etching of silicon wafers.

    Science.gov (United States)

    Ezoe, Yuichiro; Moriyama, Teppei; Ogawa, Tomohiro; Kakiuchi, Takuya; Mitsuishi, Ikuyuki; Mitsuda, Kazuhisa; Aoki, Tatsuhiko; Morishita, Kohei; Nakajima, Kazuo

    2012-03-01

    Large-aperture focusing of Al K(α) 1.49 keV x-ray photons using micropore optics made from a dry-etched 4 in. (100 mm) silicon wafer is demonstrated. Sidewalls of the micropores are smoothed with high-temperature annealing to work as x-ray mirrors. The wafer is bent to a spherical shape to collect parallel x rays into a focus. Our result supports that this new type of optics allows for the manufacturing of ultralight-weight and high-performance x-ray imaging optics with large apertures at low cost. © 2012 Optical Society of America

  20. Hard X-ray sources from miniature plasma focus devices

    International Nuclear Information System (INIS)

    Raspa, V.; Silva, P.; Moreno, J.; Zambra, M.; Soto, L.

    2004-01-01

    As first stage of a program to design a repetitive pulsed radiation generator for industrial applications, two miniature plasma foci have been designed and constructed at the Chilean commission of nuclear energy. The devices operate at an energy level of the order of tens of joules (PF-50 J, 160 nF capacitor bank, 20-35 kV, 32-100 J, ∼ 150 ns time to peak current) and hundred of joules (PF-400 J, 880 nF, 20-35 kV, 176-539 J, ∼ 300 ns time to peak current). Hard X-rays are being studied in these devices operating with hydrogen. Images of metallic plates with different thickness were obtained on commercial radiographic film, Agfa Curix ST-G2, in order to characterize the energy of the hard X-ray outside of the discharge chamber of PF-400 J. An effective energy of the order of 90 keV was measured under those conditions. X ray images of different metallic objects also have been obtained. (authors)

  1. Hard X-ray sources from miniature plasma focus devices

    Energy Technology Data Exchange (ETDEWEB)

    Raspa, V. [Buenos Aires Univ., PLADEMA, CONICET and INFIP (Argentina); Silva, P.; Moreno, J.; Zambra, M.; Soto, L. [Comision Chilena de Energia Nuclear, Santiago (Chile)

    2004-07-01

    As first stage of a program to design a repetitive pulsed radiation generator for industrial applications, two miniature plasma foci have been designed and constructed at the Chilean commission of nuclear energy. The devices operate at an energy level of the order of tens of joules (PF-50 J, 160 nF capacitor bank, 20-35 kV, 32-100 J, {approx} 150 ns time to peak current) and hundred of joules (PF-400 J, 880 nF, 20-35 kV, 176-539 J, {approx} 300 ns time to peak current). Hard X-rays are being studied in these devices operating with hydrogen. Images of metallic plates with different thickness were obtained on commercial radiographic film, Agfa Curix ST-G2, in order to characterize the energy of the hard X-ray outside of the discharge chamber of PF-400 J. An effective energy of the order of 90 keV was measured under those conditions. X ray images of different metallic objects also have been obtained. (authors)

  2. SU-F-I-76: Fluoroscopic X-Ray Beam Profiles for Spectra Incorporating Copper Filtration

    Energy Technology Data Exchange (ETDEWEB)

    Wunderle, K [Cleveland Clinic Foundation, Cleveland, OH (United States); Wayne State University School of Medicine, Detroit, MI (United States); Godley, A; Shen, Z; Dong, F [Cleveland Clinic Foundation, Cleveland, OH (United States); Rakowski, J [Wayne State University School of Medicine, Detroit, MI (United States)

    2016-06-15

    Purpose: The purpose of this investigation is to characterize and quantify X-ray beam profiles for fluoroscopic x-ray beam spectra incorporating spectral (copper) filtration. Methods: A PTW (Freiburg, Germany) type 60016 silicon diode detector and PTW MP3 water tank were used to measure X-ray beam profiles for 60, 80, 100 and 120 kVp x-ray beams at five different copper filtration thicknesses ranging from 0–0.9 mm at 22 and 42 cm fields of view and depths of 1, 5, and 10 cm in both the anode-cathode axis (inplane) and cross-plane directions. All measurements were acquired on a Siemens (Erlangen, Germany) Artis ZeeGo fluoroscope inverted from the typical orientation providing an x-ray beam originating from above the water surface with the water level set at 60 cm from the focal spot. Results: X-ray beam profiles for beam spectra without copper filtration compared well to previously published data by Fetterly et al. [Med Phys, 28, 205 (2001)]. Our data collection benefited from the geometric orientation of the fluoroscope, providing a beam perpendicular to the tank water surface, rather than through a thin side wall as did the previously mentioned study. Profiles for beams with copper filtration were obtained which have not been previously investigated and published. Beam profiles in the anode-cathode axis near the surface and at lower x-ray energy exhibited substantial heel effect, which became less pronounced at greater depth. At higher energy with copper filtration in the beam, the dose falloff out-of-field became less pronounced, as would be anticipated given higher scatter photon energy. Conclusion: The x-ray beam profile data for the fluoroscopic x-ray beams incorporating copper filtration are intended for use as reference data for estimating doses to organs or soft tissue, including fetal dose, involving similar beam qualities or for comparison with mathematical models.

  3. Ion beam induced surface graphitization of CVD diamond for x-ray beam position monitor applications

    International Nuclear Information System (INIS)

    Liu, Chian; Shu, D.; Kuzay, T.M.; Wen, L.; Melendres, C.A.; Argonne National Lab., IL

    1996-01-01

    The Advanced Photon Source at ANL is a third-generation synchrotron facility that generates powerful x-ray beams on its undulator beamlines. It is important to know the position and angle of the x- ray beam during experiments. Due to very high heat flux levels, several patented x-ray beam position monitors (XBPM) exploiting chemical vapor deposition (CVD) diamond have been developed. These XBPMs have a thin layer of low-atomic-mass metallic coating so that photoemission from the x rays generate a minute but measurable current for position determination. Graphitization of the CVD diamond surface creates a very thin, intrinsic and conducting layer that can stand much higher temperatures and minimal x-ray transmission losses compared to the coated metallic layers. In this paper, a laboratory sputter ion source was used to transform selected surfaces of a CVD diamond substrate into graphite. The effect of 1-5 keV argon ion bombardment on CVD diamond surfaces at various target temperatures from 200 to 500 C was studied using Auger electron spectroscopy and in-situ electrical resistivity measurements. Graphitization after the ion bombardment has been confirmed and optimum conditions for graphitization studied. Raman spectroscopy was used to identify the overall diamond structure in the bulk of CVD diamond substrate after the ion bombardments. It was found that target temperature plays an important role in stability and electrical conductivity of the irradiated CVD diamonds

  4. Soft X-ray Focusing Telescope Aboard AstroSat: Design, Characteristics and Performance

    DEFF Research Database (Denmark)

    Singh, K; Stewart, G.; Westergaard, Niels Jørgen Stenfeldt

    2017-01-01

    The Soft X-ray focusing Telescope (SXT), India’s first X-ray telescope based on the principle of grazing incidence, was launched aboard the AstroSat and made operational on October 26, 2015. X-rays in the energy band of 0.3–8.0 keV are focussed on to a cooled charge coupled device thus providing ...

  5. Exposure reduction in general dental practice using digital x-ray imaging system for intraoral radiography with additional x-ray beam filter

    International Nuclear Information System (INIS)

    Shibuya, Hitoshi; Mori, Toshimichi; Hayakawa, Yoshihiko; Kuroyanagi, Kinya; Ota, Yoshiko

    1997-01-01

    To measure exposure reduction in general dental practice using digital x-ray imaging systems for intraoral radiography with additional x-ray beam filter. Two digital x-ray imaging systems, Pana Digital (Pana-Heraus Dental) and CDR (Schick Technologies), were applied for intraoral radiography in general dental practice. Due to the high sensitivity to x-rays, additional x-ray beam filters for output reduction were used for examination. An Orex W II (Osada Electric Industry) x-ray generator was operated at 60 kVp, 7 mA. X-ray output (air-kerma; Gy) necessary for obtaining clinically acceptable images was measured at 0 to 20 cm in 5 cm steps from the cone tip using an ionizing chamber type 660 (Nuclear Associates) and compared with those for Ektaspeed Plus film (Eastman Kodak). The Pana Digital system was used with the optional filter supplied by Pana-Heraus Dental which reduced the output to 38%. The exposure necessary to obtain clinically acceptable images was only 40% of that for the film. The CDR system was used with the Dental X-ray Beam Filter Kit (Eastman Kodak) which reduced the x-ray output to 30%. The exposure necessary to obtain clinically acceptable images was only 20% of that for the film. The two digital x-ray imaging systems, Pana Digital and CDR, provided large dose savings (60-80%) compared with Ektaspeed Plus film when applied for intraoral radiography in general dental practice. (author)

  6. X-ray luminescence computed tomography imaging via multiple intensity weighted narrow beam irradiation

    Science.gov (United States)

    Feng, Bo; Gao, Feng; Zhao, Huijuan; Zhang, Limin; Li, Jiao; Zhou, Zhongxing

    2018-02-01

    The purpose of this work is to introduce and study a novel x-ray beam irradiation pattern for X-ray Luminescence Computed Tomography (XLCT), termed multiple intensity-weighted narrow-beam irradiation. The proposed XLCT imaging method is studied through simulations of x-ray and diffuse lights propagation. The emitted optical photons from X-ray excitable nanophosphors were collected by optical fiber bundles from the right-side surface of the phantom. The implementation of image reconstruction is based on the simulated measurements from 6 or 12 angular projections in terms of 3 or 5 x-ray beams scanning mode. The proposed XLCT imaging method is compared against the constant intensity weighted narrow-beam XLCT. From the reconstructed XLCT images, we found that the Dice similarity and quantitative ratio of targets have a certain degree of improvement. The results demonstrated that the proposed method can offer simultaneously high image quality and fast image acquisition.

  7. Multilayer X-ray mirrors for formation of sub-nanometer wavelength range beams

    International Nuclear Information System (INIS)

    Akhsakhalyan, A.A.; Akhsakhalyan, A.D.; Klyuenkov, E.B.; Murav'ev, V.A.; Salashchenko, N.N.; Kharitonov, A.I.

    2005-01-01

    Paper reviews the efforts undertaken in the RF Academy of Sciences IPM within recent 5 years to design multilayer mirror systems to produce X-ray wavelength subnanometer range beams. Paper describes a process to fabricate the mentioned systems covering the procedures to obtain supersmooth surfaces of the specified shape, to deposit gradient multilayer structures on the mentioned surfaces and describes the rules to calculate the optimal parameters of mirrors. Paper presents characteristics of mirror system two types: a mirror in the shape of a parabolic cylinder to collimate radiation in the DRON-4, DRON-6 production-type X-ray diffractometers and in the shape of a quadraelliptic reflector - a new wide-aperture four-corner focusing system [ru

  8. Electron beam production and characterization for the PLEIADES Thomson X-ray source

    International Nuclear Information System (INIS)

    Brown, W.J.; Hartemann, F.V.; Tremaine, A.M.; Springer, P.T.; Le Sage, G.P.; Barty, C.P.J.; Crane, J.K.; Cross, R.R.; Fittinghoff, D.N.; Slaughter, D.R.; Rosenzweig, J.B.; Anderson, S.; Gibson, D.J.

    2002-01-01

    We report on the performance of an S-band RF photocathode electron gun and accelerator for operation with the PLEIADES Thomson x-ray source at LLNL. Simulations of beam production, transport, and focus are presented. It is shown that a 1 ps, 500 pC electron bunch with a normalized emittance of less than 5 πmm-mrad can be delivered to the interaction point. Initial electron measurements are presented. Calculations of expected x-ray flux are also performed, demonstrating an expected peak spectral brightness of 1020 photons/s/mm2/mrad2/0.1% bandwidth. Effects of RF phase jitter are also presented, and planned phase measurements and control methods are discussed

  9. X-ray topography using the forward transmitted beam under multiple-beam diffraction conditions

    Energy Technology Data Exchange (ETDEWEB)

    Tsusaka, Y., E-mail: tsusaka@sci.u-hyogo.ac.jp; Takano, H. [Graduate School of Material Science, University of Hyogo, 3-2-1, Kouto, Kamigori, Hyogo 678-1297 (Japan); Takeda, S. [SPring-8 Service Co., Ltd., 1-20-5, Kouto, Shingu, Tatsuno, Hyogo 679-5165 (Japan); Yokoyama, K.; Matsui, J. [Synchrotron Radiation Nanotechnology Center, University of Hyogo, 1-490-2, Kouto, Shingu, Tatsuno, Hyogo 679-5165 (Japan); Kagoshima, Y. [Graduate School of Material Science, University of Hyogo, 3-2-1, Kouto, Kamigori, Hyogo 678-1297 (Japan); Synchrotron Radiation Nanotechnology Center, University of Hyogo, 1-490-2, Kouto, Shingu, Tatsuno, Hyogo 679-5165 (Japan)

    2016-02-15

    X-ray topographs are taken for a sapphire wafer with the [0001] surface normal, as an example, by forward transmitted synchrotron x-ray beams combined with two-dimensional electronic arrays in the x-ray detector having a spatial resolution of 1 μm. They exhibit no shape deformation and no position shift of the dislocation lines on the topographs. Since the topography is performed under multiple-beam diffraction conditions, the topographic images of a single diffraction (two-wave approximation condition) or plural diffractions (six-wave approximation condition) can be recorded without large specimen position changes. As usual Lang topographs, it is possible to determine the Burgers vector of each dislocation line. Because of high parallelism of the incoming x-rays and linear sensitivity of the electronic arrays to the incident x-rays, the present technique can be used to visualize individual dislocations in single crystals of the dislocation density as high as 1 × 10{sup 5} cm{sup −2}.

  10. Design of parallel dual-energy X-ray beam and its performance for security radiography

    International Nuclear Information System (INIS)

    Kim, Kwang Hyun; Myoung, Sung Min; Chung, Yong Hyun

    2011-01-01

    A new concept of dual-energy X-ray beam generation and acquisition of dual-energy security radiography is proposed. Erbium (Er) and rhodium (Rh) with a copper filter were positioned in front of X-ray tube to generate low- and high-energy X-ray spectra. Low- and high-energy X-rays were guided to separately enter into two parallel detectors. Monte Carlo code of MCNPX was used to derive an optimum thickness of each filter for improved dual X-ray image quality. It was desired to provide separation ability between organic and inorganic matters for the condition of 140 kVp/0.8 mA as used in the security application. Acquired dual-energy X-ray beams were evaluated by the dual-energy Z-map yielding enhanced performance compared with a commercial dual-energy detector. A collimator for the parallel dual-energy X-ray beam was designed to minimize X-ray beam interference between low- and high-energy parallel beams for 500 mm source-to-detector distance.

  11. Manipulating Electronic States at Oxide Interfaces Using Focused Micro X-Rays from Standard Lab Sources

    NARCIS (Netherlands)

    Poccia, Nicola; Ricci, Alessandro; Coneri, F.; Stehno, Martin; Campi, Gaetano; Demitri, Nicola; Bais, Giorgio; Wang, X. Renshaw; Hilgenkamp, H.

    2015-01-01

    Recently, X-ray illumination, using synchrotron radiation, has been used to manipulate defects, stimulate self-organization, and to probe their structure. Here, we explore a method of defect-engineering low-dimensional systems using focused laboratory-scale X-ray sources. We demonstrate an

  12. Generation of linearly polarized resonant transition radiation X-ray beam

    International Nuclear Information System (INIS)

    Yajima, Kazuaki; Awata, Takaaki; Ikeda, Mitsuharu; Ikeda, Kenichi; Yogo, Akifumi; Itoh, Akio; Imanishi, Nobutsugu

    2000-01-01

    We have proposed a method to generate almost linearly polarized resonant transition radiation X rays by using a rectangular slit placed on an electron beam axis. Our calculation predicted that the linearity is 93.5% for the resonant transition radiation X-ray beam extracted through a slit of 0.5 mrad long and 0.2 mrad wide in case of 1-GeV electron beam irradiating a 7.5-μm thick Kapton foil stack. (author)

  13. Generation of linearly polarized resonant transition radiation X-ray beam

    Energy Technology Data Exchange (ETDEWEB)

    Yajima, Kazuaki; Awata, Takaaki; Ikeda, Mitsuharu; Ikeda, Kenichi; Yogo, Akifumi; Itoh, Akio; Imanishi, Nobutsugu [Kyoto Univ. (Japan). Dept. of Nuclear Engineering

    2000-03-01

    We have proposed a method to generate almost linearly polarized resonant transition radiation X rays by using a rectangular slit placed on an electron beam axis. Our calculation predicted that the linearity is 93.5% for the resonant transition radiation X-ray beam extracted through a slit of 0.5 mrad long and 0.2 mrad wide in case of 1-GeV electron beam irradiating a 7.5-{mu}m thick Kapton foil stack. (author)

  14. A split-beam probe-pump-probe scheme for femtosecond time resolved protein X-ray crystallography

    Directory of Open Access Journals (Sweden)

    Jasper J. van Thor

    2015-01-01

    Full Text Available In order to exploit the femtosecond pulse duration of X-ray Free-Electron Lasers (XFEL operating in the hard X-ray regime for ultrafast time-resolved protein crystallography experiments, critical parameters that determine the crystallographic signal-to-noise (I/σI must be addressed. For single-crystal studies under low absorbed dose conditions, it has been shown that the intrinsic pulse intensity stability as well as mode structure and jitter of this structure, significantly affect the crystallographic signal-to-noise. Here, geometrical parameters are theoretically explored for a three-beam scheme: X-ray probe, optical pump, X-ray probe (or “probe-pump-probe” which will allow experimental determination of the photo-induced structure factor amplitude differences, ΔF, in a ratiometric manner, thereby internally referencing the intensity noise of the XFEL source. In addition to a non-collinear split-beam geometry which separates un-pumped and pumped diffraction patterns on an area detector, applying an additional convergence angle to both beams by focusing leads to integration over mosaic blocks in the case of well-ordered stationary protein crystals. Ray-tracing X-ray diffraction simulations are performed for an example using photoactive yellow protein crystals in order to explore the geometrical design parameters which would be needed. The specifications for an X-ray split and delay instrument that implements both an offset angle and focused beams are discussed, for implementation of a probe-pump-probe scheme at the European XFEL. We discuss possible extension of single crystal studies to serial femtosecond crystallography, particularly in view of the expected X-ray damage and ablation due to the first probe pulse.

  15. Evaluation device of diagnostic X-ray beam

    International Nuclear Information System (INIS)

    Pela, Carlos Alberto; Paula, Eldereis de; Bruco, Jose Luiz; Ghilardi Netto, Thomaz

    1996-01-01

    A device developed to determine the physical parameters useful to the evaluation of both dental and medical X-ray equipment is presented. Nine detectors connected each one to a signal amplifier are used. The amplifiers output has being connected to an analog to digital interface plugged in a PC-AT microcomputer. The X-ray pass through filters before reaching the detectors. The data collected by microcomputer are used to calculate the kVp and other factors as total tube filtration, waveform, half-value layer, exposure rate and exposure time

  16. Time resolved x-ray photography of a dense plasma focus

    International Nuclear Information System (INIS)

    Burnett, J.C.; Meyer, J.; Rankin, G.

    1977-01-01

    The temporal development of the hot plasma in a dense plasma focus is studied by x-ray streak photography of approximately 2 ns resolution time. It is shown that initially a uniform x-ray emitting pinch plasma is formed which subsequently cools down until x-ray emission stops after approximately 50 ns. At a time of around 100 ns after initial x-ray emission coinciding with the break-up time of the pinch a second burst of x-rays is observed coming from small localized regions. The observations are compared with results obtained from time-resolved shadow and schlieren photography of a similar dense focus discharge. (author)

  17. Evaluation of the Beam Quality of Intraoral X-ray Equipment using Intraoral Standard Films

    International Nuclear Information System (INIS)

    Lee, Sang Sub; Kwon, Hyok Rak; Sim, Woo Hyoun; Oh, Seung Hyoun; Lee, Ji Youn; Jeon, Kug Jin; Kim, Kee Deog; Park, Chang Seo

    2000-01-01

    This study was to evaluate the beam quality of intraoral X-ray equipment used at Yonsei University Dental Hospital (YUDH) using the half value layer (HVL) and the characteristic curve of intraoral standard X-ray film. The study was done using the intraoral X-ray equipment used at each clinical department at YUDH. Aluminum filter was used to determine the HVL. Intraoral standard film was used to get the characteristic curve of each intraoral X-ray equipment. Most of the HVLs of intraoral X-ray equipment were higher than the least recommended thickness, but the REX 601 model used at the operative dentistry department and the X-707 model used at the pediatric dentistry department had HVLs lower than the recommended thickness. The slopes of the characteristic curves of films taken using the PANPAS 601 model and REX 601 model at operative dentistry department, the X-70S model of prosthodontic dentistry department, and the REX 601 model at the student clinic were relatively low. HVL and the characteristic curve of X-ray film can be used to evaluate the beam quality of intraoral X-ray equipment. In order to get the best X-ray films with the least radiation exposure to patients and best diagnostic information in clinical dentistry, X-ray equipment should be managed in the planned and organized fashion.

  18. An MCNP-based model of a medical linear accelerator x-ray photon beam.

    Science.gov (United States)

    Ajaj, F A; Ghassal, N M

    2003-09-01

    The major components in the x-ray photon beam path of the treatment head of the VARIAN Clinac 2300 EX medical linear accelerator were modeled and simulated using the Monte Carlo N-Particle radiation transport computer code (MCNP). Simulated components include x-ray target, primary conical collimator, x-ray beam flattening filter and secondary collimators. X-ray photon energy spectra and angular distributions were calculated using the model. The x-ray beam emerging from the secondary collimators were scored by considering the total x-ray spectra from the target as the source of x-rays at the target position. The depth dose distribution and dose profiles at different depths and field sizes have been calculated at a nominal operating potential of 6 MV and found to be within acceptable limits. It is concluded that accurate specification of the component dimensions, composition and nominal accelerating potential gives a good assessment of the x-ray energy spectra.

  19. Micro-beam X-ray fluorescence and absorption imaging techniques at the IAEA Laboratories

    International Nuclear Information System (INIS)

    Wegrzynek, Dariusz; Markowicz, A.; Bamford, S.; Chinea-Cano, E.; Bogovac, M.

    2005-01-01

    X-ray tube based, micro-beam X-ray fluorescence scanning spectrometer has been equipped with two energy dispersive X-ray detectors. The two-detector configuration allows for simultaneous collection of X-ray fluorescence (XRF) and transmitted X-ray beam signals with a spatial resolution in the range of 10-50 μm, depending on the X-ray focussing element in use. The XRF signal is collected with a standard, liquid nitrogen cooled Si(Li) detector. The X-ray beam transmitted through the sample is acquired with a thermoelectrically cooled, silicon drift (SD) detector. The data acquisition is carried out in a fully automatic way under control of the SPECTOR-LOCATOR software. The software controls the scanning procedure and X-ray spectra acquisition during the scan. The energy dispersive X-ray spectra collected at every 'pixel' are stored for off-line processing. For selected regions of interest (ROI's), the element maps are constructed and displayed on-line. The spectrometer has been used for mapping elemental distributions and for performing 2D- and 3D-tomograpic imaging of minute objects in X-ray absorption and in X-ray fluorescence mode. A unique feature of the described system is simultaneous utilization of the two detectors, Si(Li) and SD, which adds new options for quantitative analysis and data interpretation. Examples of elemental mapping and 3D tomographic imaging as well as the advanced features of the SPECTOR-LOCATOR measurement control and data acquisition software are presented in this work

  20. Installation And Test Of Electron Beam Generation System To Produce Far-Infrared Radiation And X-Ray Pulses

    International Nuclear Information System (INIS)

    Wichaisirimongkol, Pathom; Jinamoon, Witoon; Khangrang, Nopadon; Kusoljariyakul, Keerati; Rhodes, Michael W.; Rimjaem, Sakhorn; Saisut, Jatuporn; Chitrlada, Thongbai; Vilaithong, Thiraphat; Wiedemann, Helmut

    2005-10-01

    SURIYA project at the Fast Neutron Research Facility, Chiang Mai University, aims to establish a facility to generate femtosecond electron beams. This electron beam can be used to generate high intensity far-infrared radiation and ultra-short X-ray pulses. The main components of the system are a 3 MeV RF electron gun with a thermionic cathode, an a-magnet as a bunch compressor, and post acceleration 15-20 MeV by a linear accelerator (linac). Between the main components, there are focusing quadrupole magnets and steering magnets to maintain the electron beam within a high vacuum tube. At the end of the beam transport line, a dipole magnet has been installed to function as a beam dump and an energy spectrometer. After the installation and testing of individual major components were completed, we have been investigating the generation of the electron beam, intense far- infrared radiation and ultra short X-ray pulses

  1. Single-shot beam-position monitor for x-ray free electron laser

    Science.gov (United States)

    Tono, Kensuke; Kudo, Togo; Yabashi, Makina; Tachibana, Takeshi; Feng, Yiping; Fritz, David; Hastings, Jerome; Ishikawa, Tetsuya

    2011-02-01

    We have developed an x-ray beam-position monitor for detecting the radiation properties of an x-ray free electron laser (FEL). It is composed of four PIN photodiodes that detect backscattered x-rays from a semitransparent diamond film placed in the beam path. The signal intensities from the photodiodes are used to compute the beam intensity and position. A proof-of-principle experiment at a synchrotron light source revealed that the error in the beam position is reduced to below 7 μm by using a nanocrystal diamond film prepared by plasma-enhanced chemical vapor deposition. Owing to high dose tolerance and transparency of the diamond film, the monitor is suitable for routine diagnostics of extremely intense x-ray pulses from the FEL.

  2. Development and commissioning of an x-ray beam alignment flag for NSLS-II

    Energy Technology Data Exchange (ETDEWEB)

    Kosciuk, B., E-mail: bkosciuk@bnl.gov; Hu, Y.; Keister, J.; Seletskiy, S. [National Synchrotron Light Source-II, Brookhaven National Laboratory, Upton, New York 11973 (United States)

    2016-07-27

    The NSLS-II Synchrotron Light Source is a 3 GeV electron storage ring recently commissioned and is now entering operations at Brookhaven National Laboratory. One of the major tasks was to commission the six project beamline front ends which required a diagnostic to resolve x-ray beam position for the purpose of beam alignment at low current. Since none of the front ends were outfitted with any x-ray diagnostics in the baseline design, an x-ray beam profile monitor or “flag” that could be easily installed into existing front end vacuum chambers was proposed to satisfy this requirement. Here we present the development of this novel device which utilizes a polycrystalline CVD diamond luminescent screen to produce a visible image of the x-ray beam cross-section and is then captured with a CCD camera.

  3. Effect of X-ray suppression system upon parameters of electrostatic accelerator ion beam

    Directory of Open Access Journals (Sweden)

    I. G. Ignat'ev

    2014-12-01

    Full Text Available Experimental study results are presented for a beam profile and emittance of an electrostatic accelerator “Sokol” before and after being equipped with magnet X-ray suppression system.

  4. Using a tandem ionization chamber for quality control of X-ray beams

    International Nuclear Information System (INIS)

    Yoshizumi, Maira T.; Caldas, Linda V.E.

    2011-01-01

    X-ray beam qualities are defined by both the mean energies and by the half-value layers (HVL). Many international protocols use the half-value layer and the beam voltage to characterize the X-ray beam quality. A quality control program for X-ray equipment includes the constancy check of beam qualities, i.e., the periodical verification of the half-value layer, which can be a time consumable procedure. A tandem ionization chamber, developed at Instituto de Pesquisas Energeticas e Nucleares, was used to determine the HVL and its constancy for five radiotherapy standard beam qualities. This ionization chamber is composed by two sensitive volumes with inner electrodes made of different materials: aluminum and graphite. The beam quality constancy check test was performed during two months and the maximum variation obtained was 1.24% for the radiation beam quality T-10. This result is very satisfactory according to national recommendations. (author)

  5. Sub-500  nm hard x ray focusing by compound long kinoform lenses.

    Science.gov (United States)

    Liao, Keliang; Liu, Jing; Liang, Hao; Wu, Xuehui; Zhang, Kai; Yuan, Qingxi; Yi, Futing; Sheng, Weifan

    2016-01-01

    The focusing performance of polymethyl methacrylate compound long kinoform lenses with 70 μm aperture and 19.5 mm focal length was characterized with 8 keV x rays using the knife-edge scan method at the 4W1A transmission x-ray microscope beamline of Beijing Synchrotron Radiation Facility. The experiment result shows a best FWHM focus size of 440 nm with 31% diffraction efficiency.

  6. X-ray beam size measurements on the Advanced Test Accelerator

    International Nuclear Information System (INIS)

    Struve, K.W.; Chambers, F.W.; Lauer, E.J.; Slaughter, D.R.

    1986-01-01

    The electron beam size has been determined on the Advanced Test Accelerator (ATA) by intercepting the beam with a target and measuring the resulting x-ray intensity as a function of time as the target is moved through the beam. Several types of targets have been used. One is a tantalum rod which extends completely across the drift chamber. Another is a tungsten powder filled carbon crucible. Both of these probes are moved from shot to shot so that the x-ray signal intensity varies with probe position. A third is a larger tantalum disk which is inserted on beam axis to allow determining beam size on a one shot basis. The x-ray signals are detected with an MCP photomultiplier tube located at 90 0 to the beamline. It is sufficiently shielded to reject background x-rays and neutrons. The signals were digitized, recorded and later unfolded to produce plots of x-ray intensity versus probe position for several times during the pulse. The presumption that the x-ray intensity is proportional to beam current density is checked computationally. Details of the probe construction and PMT shielding, as well as sample measurements are given

  7. Determination of the effective energy in X-rays standard beams, mammography level

    Energy Technology Data Exchange (ETDEWEB)

    Correa, Eduardo de Lima; Vivolo, Vitor; Potiens, Maria da Penha A., E-mail: Vivolo@ipen.b, E-mail: mppalbu@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    The X-rays beams used in diagnostic radiology are heterogeneous. This means that, in a radiological beam, it can be found photons with different energies. Because of that is common to work with the concept of effective energy. In this study the effective energy of an X-rays system used in instruments calibration was determined, as part of the mammography radiation qualities establishment. The procedure presented here was developed based on information found in the literature. The X-ray mass attenuation coefficients for aluminum, given by NIST web site, were used and the mathematical adjusts were done using the Origin 8.0 program. The results are part of the mammographic X-rays beams characteristics determination and it is important to keep the quality of this reference system. (author)

  8. 13.1 micrometers hard X-ray focusing by a new type monocapillary X-ray optic designed for common laboratory X-ray source

    Science.gov (United States)

    Sun, Xuepeng; zhang, Xiaoyun; Zhu, Yu; Wang, Yabing; Shang, Hongzhong; Zhang, Fengshou; Liu, Zhiguo; Sun, Tianxi

    2018-04-01

    A new type of monocapillary X-ray optic, called 'two bounces monocapillary X-ray optics' (TBMXO), is proposed for generating a small focal spot with high power-density gain for micro X-ray analysis, using a common laboratory X-ray source. TBMXO is consists of two parts: an ellipsoidal part and a tapered part. Before experimental testing, the TBMXO was simulated by the ray tracing method in MATLAB. The simulated results predicted that the proposed TBMXO would produce a smaller focal spot with higher power-density gain than the ellipsoidal monocapillary X-ray optic (EMXO). In the experiment, the TBMXO performance was tested by both an optical device and a Cu target X-ray tube with focal spot of 100 μm. The results indicated that the TBMXO had a slope error of 57.6 μrad and a 13.1 μm focal spot and a 1360 gain in power density were obtained.

  9. High resolution beam profiling of X-ray free electron laser radiation by polymer imprint development.

    Science.gov (United States)

    Rösner, Benedikt; Döring, Florian; Ribič, Primož R; Gauthier, David; Principi, Emiliano; Masciovecchio, Claudio; Zangrando, Marco; Vila-Comamala, Joan; De Ninno, Giovanni; David, Christian

    2017-11-27

    High resolution metrology of beam profiles is presently a major challenge at X-ray free electron lasers. We demonstrate a characterization method based on beam imprints in poly (methyl methacrylate). By immersing the imprints formed at 47.8 eV into organic solvents, the regions exposed to the beam are removed similar to resist development in grayscale lithography. This allows for extending the sensitivity of the method by more than an order of magnitude compared to the established analysis of imprints created solely by ablation. Applying the Beer-Lambert law for absorption, the intensity distribution in a micron-sized focus can be reconstructed from one single shot with a high dynamic range, exceeding 10 3 . The procedure described here allows for beam characterization at free electron lasers revealing even faint beam tails, which are not accessible when using ablation imprint methods. We demonstrate the greatly extended dynamic range on developed imprints taken in focus of conventional Fresnel zone plates and spiral zone plates producing beams with a topological charge.

  10. Focusing Optics for High-Energy X-ray Diffraction

    DEFF Research Database (Denmark)

    Leinert, U.; Schulze, C.; Honkimäki, V.

    1998-01-01

    Novel focusing optical devices have been developed for synchrotron radiation in the energy range 40-100 keV. Firstly, a narrow-band-pass focusing energy-tuneable fixed-exit monochromator was constructed by combining meridionally bent Laue and Bragg crystals. Dispersion compensation was applied...

  11. Residual stress measurement with focused acoustic waves and direct comparison with X-ray diffraction stress measurements

    International Nuclear Information System (INIS)

    Sathish, Shamachary; Moran, Thomas J.; Martin, Richard W.; Reibel, Richard

    2005-01-01

    The technique of measuring small changes in acoustic wave velocity due to external or internal stress has been used for quantitative determination of residual stress in materials during the last decade. Application of similar methodology with focused acoustic waves leads to residual stress measurement with spatial resolution of a few millimeters to a few microns. The high spatial resolution residual stress measurement required development of new methodologies in both the design of acoustic lenses and the instrumentation for acoustic wave velocity determination. This paper presents two new methodologies developed for the measurement of residual stress with spatial resolution of a few millimeters. The design of new type of acoustic lens for achieving higher spatial resolution in residual stress measurement is introduced. Development of instrumentation for high precision local surface wave velocity measurement will be presented. Residual stresses measured around a crack tip in a sample of Ti-6A1-4V using a focused beam will be compared with X-ray diffraction measurements performed on the same region of the sample. Results of residual stress measurements along a direction perpendicular to the electron beam weld in a sample of Ti-6A1-4V, determined using focused acoustic waves and X-ray diffraction technique, are also presented. The spatial resolution and penetration depth of X-rays and focused acoustic beams with reference to residual stress measurements are discussed

  12. A reconstruction method for cone-beam differential x-ray phase-contrast computed tomography.

    Science.gov (United States)

    Fu, Jian; Velroyen, Astrid; Tan, Renbo; Zhang, Junwei; Chen, Liyuan; Tapfer, Arne; Bech, Martin; Pfeiffer, Franz

    2012-09-10

    Most existing differential phase-contrast computed tomography (DPC-CT) approaches are based on three kinds of scanning geometries, described by parallel-beam, fan-beam and cone-beam. Due to the potential of compact imaging systems with magnified spatial resolution, cone-beam DPC-CT has attracted significant interest. In this paper, we report a reconstruction method based on a back-projection filtration (BPF) algorithm for cone-beam DPC-CT. Due to the differential nature of phase contrast projections, the algorithm restrains from differentiation of the projection data prior to back-projection, unlike BPF algorithms commonly used for absorption-based CT data. This work comprises a numerical study of the algorithm and its experimental verification using a dataset measured with a three-grating interferometer and a micro-focus x-ray tube source. Moreover, the numerical simulation and experimental results demonstrate that the proposed method can deal with several classes of truncated cone-beam datasets. We believe that this feature is of particular interest for future medical cone-beam phase-contrast CT imaging applications.

  13. X-ray beam-position feedback system with easy-to-use beam-position monitor.

    Science.gov (United States)

    Park, Jae Yeon; Kim, Yesul; Lee, Sangsul; Lim, Jun

    2018-05-01

    X-ray beam-position stability is indispensable in cutting-edge experiments using synchrotron radiation. Here, for the first time, a beam-position feedback system is presented that utilizes an easy-to-use X-ray beam-position monitor incorporating a diamond-fluorescence screen. The acceptable range of the monitor is above 500 µm and the feedback system maintains the beam position within 3 µm. In addition to being inexpensive, the system has two key advantages: it works without a scale factor for position calibration, and it has no dependence on X-ray energy, X-ray intensity, beam size or beam shape.

  14. The Ferrara hard X-ray facility for testing/calibrating hard X-ray focusing telescopes

    Science.gov (United States)

    Loffredo, Gianluca; Frontera, Filippo; Pellicciotta, Damiano; Pisa, Alessandro; Carassiti, Vito; Chiozzi, Stefano; Evangelisti, Federico; Landi, Luca; Melchiorri, Michele; Squerzanti, Stefano

    2005-12-01

    We will report on the current configuration of the X-ray facility of the University of Ferrara recently used to perform reflectivity tests of mosaic crystals and to calibrate the experiment JEM X aboard Integral. The facility is now located in the technological campus of the University of Ferrara in a new building (named LARIX laboratory= LARge Italian X-ray facility) that includes a tunnel 100 m long with, on the sides, two large experimental rooms. The facility is being improved for determining the optical axis of mosaic crystals in Laue configuration, for calibrating Laue lenses and hard X-ray mirror prototypes.

  15. A water-cooled x-ray monochromator for using off-axis undulator beam

    International Nuclear Information System (INIS)

    Khounsary, A.; Maser, J.

    2000-01-01

    Undulator beamlines at third-generation synchrotrons x-ray sources are designed to use the high-brilliance radiation that is contained in the central cone of the generated x-ray beams. The rest of the x-ray beam is often unused. Moreover, in some cases, such as in the zone-plate-based microfocusing beamlines, only a small part of the central radiation cone around the optical axis is used. In this paper, a side-station branch line at the Advanced Photon Source that takes advantage of some of the unused off-axis photons in a microfocusing x-ray beamline is described. Detailed information on the design and analysis of a high-heat-load water-cooled monochromator developed for this beamline is provided

  16. Source apportionment of aerosol particles using polycapillary slightly focusing X-ray lens

    Energy Technology Data Exchange (ETDEWEB)

    Sun Tianxi [Key Laboratory of Beam Technology and Materials Modification of Ministry of Education, Beijing Normal University, Beijing 100875 (China) and Institute of Low Energy Nuclear Physics, Beijing Normal University, Beijing 100875 (China) and Beijing Radiation Center, Beijing 100875 (China)], E-mail: stxbeijing@163.com; Liu Zhiguo [Key Laboratory of Beam Technology and Materials Modification of Ministry of Education, Beijing Normal University, Beijing 100875 (China) and Institute of Low Energy Nuclear Physics, Beijing Normal University, Beijing 100875 (China) and Beijing Radiation Center, Beijing 100875 (China)], E-mail: liuzgbeijing@163.com; Zhu Guanghua; Liu Hui [Key Laboratory of Beam Technology and Materials Modification of Ministry of Education, Beijing Normal University, Beijing 100875 (China); Institute of Low Energy Nuclear Physics, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Ma Yongzhong [Center for Disease Control and Prevention of Beijing, Beijing 100013 (China); Xu Qing [Institute of High Energy Physics, Chinese Academy of Science, Beijing 100039 (China); Li Yude; Wang Guangpu; Luo Ping; Pan Qiuli; Ding Xunliang [Key Laboratory of Beam Technology and Materials Modification of Ministry of Education, Beijing Normal University, Beijing 100875 (China); Institute of Low Energy Nuclear Physics, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China)

    2009-06-11

    A micro-X-ray fluorescence (Micro-XRF) spectrometer based on a polycapillary slightly focusing X-ray lens (PSFXRL) and laboratory X-ray source was designed to carry out the source apportionment of aerosol particles. In the distribution curve of the X-ray intensity in the focal spot of PSFXRL, there was a plateau with a diameter of about 65 {mu}m. The uniformity of this plateau was about 3%. This was helpful in measuring the XRF spectrum of a single aerosol particle in which the element distributions are not uniform. The minimum detection limit (MDL) of this Micro-XRF spectrometer was 15 ppm for the Fe-K{sub {alpha}}. The origins of the aerosol particles at the exit of a subway station and a construction site were apportioned. This Micro-XRF spectrometer has potential applications in analysis of single aerosol particles.

  17. Characterization and control of femtosecond electron and X-ray beams at free-electron lasers

    International Nuclear Information System (INIS)

    Behrens, Christopher

    2012-11-01

    X-ray free-electron lasers (FELs) open up new frontiers in photon science, and in order to take full advantage of these unique accelerator-based light sources, the characterization and control of the femtosecond electron and X-ray beams is essential. Within this cumulative thesis, recent results achieved within the active research field of femtosecond electron and X-ray beams at FELs are reported.The basic principles of X-ray FELs are described, and concepts of longitudinal electron beam diagnostics with femtosecond accuracy are covered. Experimental results obtained with a transverse deflecting structure (TDS) and spectroscopy of coherent terahertz radiation are presented, and the suppression of coherent optical radiation effects, required for diagnostics utilizing a TDS, is demonstrated. Control of the longitudinal phase space by using multiple radio frequencies for longitudinal electron beam tailoring is presented, and a new technique of reversible electron beam heating with two TDSs is described. For the characterization of femtosecond X-ray pulses, a novel method based on dedicated longitudinal phase space diagnostics for electron beams is introduced, and recent measurements with a streaking technique using external terahertz fields are presented.

  18. Characterization and control of femtosecond electron and X-ray beams at free-electron lasers

    Energy Technology Data Exchange (ETDEWEB)

    Behrens, Christopher

    2012-11-15

    X-ray free-electron lasers (FELs) open up new frontiers in photon science, and in order to take full advantage of these unique accelerator-based light sources, the characterization and control of the femtosecond electron and X-ray beams is essential. Within this cumulative thesis, recent results achieved within the active research field of femtosecond electron and X-ray beams at FELs are reported.The basic principles of X-ray FELs are described, and concepts of longitudinal electron beam diagnostics with femtosecond accuracy are covered. Experimental results obtained with a transverse deflecting structure (TDS) and spectroscopy of coherent terahertz radiation are presented, and the suppression of coherent optical radiation effects, required for diagnostics utilizing a TDS, is demonstrated. Control of the longitudinal phase space by using multiple radio frequencies for longitudinal electron beam tailoring is presented, and a new technique of reversible electron beam heating with two TDSs is described. For the characterization of femtosecond X-ray pulses, a novel method based on dedicated longitudinal phase space diagnostics for electron beams is introduced, and recent measurements with a streaking technique using external terahertz fields are presented.

  19. Long-term stability of beam quality and output of conventional X-ray units

    OpenAIRE

    Fukuda, Atsushi; Matsubara, Kosuke; Miyati, Toshiaki

    2015-01-01

    Conventional diagnostic X-ray units are used for radiographic imaging in many countries. For obtaining entrance surface doses, a numerical dose determination method has been applied in Japan. Although this technique is effective, it has to account for errors, particularly fluctuations, due to the beam quality and output of X-ray tubes. As a part of our quality control procedures, we recorded the entrance surface air kerma, tube voltage, and half-value layer measurements made for four diagnost...

  20. Dynamical x-ray diffraction studies of interfacial strain in superlattices grown by molecular beam epitaxy

    International Nuclear Information System (INIS)

    Vandenberg, J.M.; Chu, S.N.G.; Hamm, R.A.; Panish, M.B.; Ritter, D.; Mancrander, A.T.

    1992-01-01

    This paper reports on dynamical X-ray diffraction studies that have been carried out for lattice-matched InGaAs/InP superlattices grown by modified molecular beam epitaxy (MBE) techniques. The (400) X-ray satellite pattern, which is predominantly affected by the strain modulation, was analyzed. The strain and thickness of the actual layers including the presence of strained interfacial regions were determined

  1. A multiple CCD X-ray detector and its first operation with synchrotron radiation X-ray beam

    CERN Document Server

    Suzuki, M; Kumasaka, T; Sato, K; Toyokawa, H; Aries, I F; Jerram, P A; Ueki, T

    1999-01-01

    A 4x4 array structure of 16 identical CCD X-ray detector modules, called the multiple CCD X-ray detector system (MCCDX), was submitted to its first synchrotron radiation experiment at the protein crystallography station of the RIKEN beamline (BL45XU) at the SPring-8 facility. An X-ray diffraction pattern of cholesterol powder was specifically taken in order to investigate the overall system performance.

  2. An experimental evaluation of monochromatic x-ray beam position monitors at diamond light source

    Energy Technology Data Exchange (ETDEWEB)

    Bloomer, Chris, E-mail: chris.bloomer@diamond.ac.uk; Rehm, Guenther; Dolbnya, Igor P. [Diamond Light Source Ltd, Oxfordshire (United Kingdom)

    2016-07-27

    Maintaining the stability of the X-ray beam relative to the sample point is of paramount importance for beamlines and users wanting to perform cutting-edge experiments. The ability to detect, and subsequently compensate for, variations in X-ray beam position with effective diagnostics has multiple benefits: a reduction in commissioning and start-up time, less ‘down-time’, and an improvement in the quality of acquired data. At Diamond Light Source a methodical evaluation of a selection of monochromatic X-ray Beam Position Monitors (XBPMs), using a range of position detection techniques, and from a range of suppliers, was carried out. The results of these experiments are presented, showing the measured RMS noise on the position measurement of each device for a given flux, energy, beam size, and bandwidth. A discussion of the benefits and drawbacks of each of the various devices and techniques is also included.

  3. An experimental evaluation of monochromatic x-ray beam position monitors at diamond light source

    International Nuclear Information System (INIS)

    Bloomer, Chris; Rehm, Guenther; Dolbnya, Igor P.

    2016-01-01

    Maintaining the stability of the X-ray beam relative to the sample point is of paramount importance for beamlines and users wanting to perform cutting-edge experiments. The ability to detect, and subsequently compensate for, variations in X-ray beam position with effective diagnostics has multiple benefits: a reduction in commissioning and start-up time, less ‘down-time’, and an improvement in the quality of acquired data. At Diamond Light Source a methodical evaluation of a selection of monochromatic X-ray Beam Position Monitors (XBPMs), using a range of position detection techniques, and from a range of suppliers, was carried out. The results of these experiments are presented, showing the measured RMS noise on the position measurement of each device for a given flux, energy, beam size, and bandwidth. A discussion of the benefits and drawbacks of each of the various devices and techniques is also included.

  4. Controlling X-ray beam trajectory with a flexible hollow glass fibre

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Yoshihito, E-mail: yotanaka@riken.jp [RIKEN, 1-1-1 Kouto, Sayo-cho, Hyogo 679-5148 (Japan); Kwansei Gakuin University, Gakuen, Sanda, Hyogo 669-1337 (Japan); Nakatani, Takashi; Onitsuka, Rena [Kwansei Gakuin University, Gakuen, Sanda, Hyogo 669-1337 (Japan); Sawada, Kei [RIKEN, 1-1-1 Kouto, Sayo-cho, Hyogo 679-5148 (Japan); Takahashi, Isao [Kwansei Gakuin University, Gakuen, Sanda, Hyogo 669-1337 (Japan)

    2014-01-01

    X-ray beam trajectory control has been performed by using a 1.5 m-long flexible hollow glass fibre. A two-dimensional scan of a synchrotron radiation beam was demonstrated for X-ray absorption mapping. A metre-length flexible hollow glass fibre with 20 µm-bore and 1.5 mm-cladding diameters for transporting a synchrotron X-ray beam and controlling the trajectory has been examined. The large cladding diameter maintains a moderate curvature to satisfy the shallow glancing angle of total reflection. The observed transmission efficiency was more than 20% at 12.4 keV. As a demonstration, a wide-area scan of a synchrotron radiation beam was performed to identify the elements for a fixed metal film through its absorption spectra.

  5. Current sheath curvature correlation with the neon soft x-ray emission from plasma focus device

    International Nuclear Information System (INIS)

    Zhang, T; Lin, X; Chandra, K A; Tan, T L; Springham, S V; Patran, A; Lee, P; Lee, S; Rawat, R S

    2005-01-01

    The insulator sleeve length is one of the major parameters that can severely affect the neon soft x-ray yield from a plasma focus. The effect of the insulation sleeve length on various characteristic timings of plasma focus discharges and hence the soft x-ray emission characteristics has been investigated using a resistive divider. The pinhole images and laser shadowgraphy are used to explain the observed variation in the average soft x-ray yield (measured using a diode x-ray spectrometer) with variation of the insulator sleeve length. We have found that for a neon filled plasma focus device the change in insulator sleeve length changes the current sheath curvature angle and thus the length of the focused plasma column. The optimized current sheath curvature angle is found to be between 39 0 and 41 0 , at the specific axial position of 6.2-9.3 cm from the cathode support plate, for our 3.3 kJ plasma focus device. A strong dependence of the neon soft x-ray yield on the current sheath curvature angle has thus been reported

  6. Finite thickness effect of a zone plate on focusing hard x-rays

    International Nuclear Information System (INIS)

    Yun, W.B.; Chrzas, J.; Viccaro, P.J.

    1992-01-01

    Spatial resolution and focusing efficiency are two important properties of a zone plate in x-ray focusing applications. A general expression of the zone plate equation describing its zone registration is derived from the interference of spherical waves emited from two mutually coherent point sources. An analytical expression of the focusing efficiency in terms of the zone plate thickness and x-ray refractive indices of the zones is also derived. Validity condition for using this expression is considered. Thickness required for obtaining adequate focusing efficiency is calculated as a function of x-ray energy for several representative materials. The spatial resolution of a finite thickness zone plate is worse than that of an infinetly thin zone plate. which is approximately equal to the smallest zone width of the zone plate. The effect of the finite thickness on the spatial resolution is considered

  7. X-ray beam-shaping via deformable mirrors: Analytical computation of the required mirror profile

    International Nuclear Information System (INIS)

    Spiga, Daniele; Raimondi, Lorenzo; Svetina, Cristian; Zangrando, Marco

    2013-01-01

    X-ray mirrors with high focusing performances are in use in both mirror modules for X-ray telescopes and in synchrotron and FEL (Free Electron Laser) beamlines. A degradation of the focus sharpness arises in general from geometrical deformations and surface roughness, the former usually described by geometrical optics and the latter by physical optics. In general, technological developments are aimed at a very tight focusing, which requires the mirror profile to comply with the nominal shape as much as possible and to keep the roughness at a negligible level. However, a deliberate deformation of the mirror can be made to endow the focus with a desired size and distribution, via piezo actuators as done at the EIS-TIMEX beamline of FERMI@Elettra. The resulting profile can be characterized with a Long Trace Profilometer and correlated with the expected optical quality via a wavefront propagation code. However, if the roughness contribution can be neglected, the computation can be performed via a ray-tracing routine, and, under opportune assumptions, the focal spot profile (the Point Spread Function, PSF) can even be predicted analytically. The advantage of this approach is that the analytical relation can be reversed; i.e., from the desired PSF the required mirror profile can be computed easily, thereby avoiding the use of complex and time-consuming numerical codes. The method can also be suited in the case of spatially inhomogeneous beam intensities, as commonly experienced at synchrotrons and FELs. In this work we expose the analytical method and the application to the beam shaping problem

  8. An investigation of dose changes for therapeutic kilovoltage x-ray beams with underlying lead shielding

    International Nuclear Information System (INIS)

    Hill, Robin; Healy, Brendan; Holloway, Lois; Baldock, Clive

    2007-01-01

    Kilovoltage x-ray beams are used to treat cancer on or close to the skin surface. Many clinical cases use high atomic number materials as shielding to reduce dose to underlying healthy tissues. In this work, we have investigated the effect on both the surface dose and depth doses in a water phantom with lead shielding at depth in the phantom. The EGSnrc Monte Carlo code was used to simulate the water phantom and to calculate the surface doses and depth doses using primary x-ray beam spectra derived from an analytical model. The x-ray beams were in the energy range of 75-135 kVp with field sizes of 2, 5 and 8 cm diameter. The lead sheet was located beneath the water surface at depths ranging from 0.5-7.5 cm. The surface dose decreased as the lead was positioned closer to the water surface and as the field size was increased. The variation in surface dose as a function of x-ray beam energy was only small but the maximum reduction occurred for the 100 kVp x-ray beam. For the 8 cm diameter field with the lead at 1 cm depth and using the 100 kVp x-ray beam, the surface dose was reduced to 0.898 of the surface dose in the water phantom only. Measured surface dose changes, using a Farmer-type ionization chamber, agreed with the Monte Carlo calculated doses. Calculated depth doses in water with a lead sheet positioned below the surface showed that the dose fall-off increased as the lead was positioned closer to the water surface as compared to the depth dose in the water phantom only. Monte Carlo calculations of the total x-ray beam spectrum at the water surface showed that the total fluence decreased due to a reduction in backscatter from within the water and very little backscatter from the lead. The mean energy of the x-ray spectrum varied less than 1 keV, with the lead at 1 cm beneath the water phantom surface. As the Monte Carlo calculations showed good agreement with the measured results, this method can be used to verify surface dose changes in clinical situations

  9. A Monte Carlo approach for simulating the propagation of partially coherent x-ray beams

    DEFF Research Database (Denmark)

    Prodi, A.; Bergbäck Knudsen, Erik; Willendrup, Peter Kjær

    2011-01-01

    Advances at SR sources in the generation of nanofocused beams with a high degree of transverse coherence call for effective techniques to simulate the propagation of partially coherent X-ray beams through complex optical systems in order to characterize how coherence properties such as the mutual...

  10. Phase contrast imaging using a micro focus x-ray source

    Science.gov (United States)

    Zhou, Wei; Majidi, Keivan; Brankov, Jovan G.

    2014-09-01

    Phase contrast x-ray imaging, a new technique to increase the imaging contrast for the tissues with close attenuation coefficients, has been studied since mid 1990s. This technique reveals the possibility to show the clear details of the soft tissues and tumors in small scale resolution. A compact and low cost phase contrast imaging system using a conventional x-ray source is described in this paper. Using the conventional x-ray source is of great importance, because it provides the possibility to use the method in hospitals and clinical offices. Simple materials and components are used in the setup to keep the cost in a reasonable and affordable range.Tungsten Kα1 line with the photon energy 59.3 keV was used for imaging. Some of the system design details are discussed. The method that was used to stabilize the system is introduced. A chicken thigh bone tissue sample was used for imaging followed by the image quality, image acquisition time and the potential clinical application discussion. High energy x-ray beam can be used in phase contrast imaging. Therefore the radiation dose to the patients can be greatly decreased compared to the traditional x-ray radiography.

  11. X-ray Beam Spectral Reconstruction Using Laplace Transform and Attenuation Curves

    International Nuclear Information System (INIS)

    Maeng, Seongjin; Lee, Sang Hoo; Kwon, Dahye; Seo, Jihye; Seo, Kyung Won

    2015-01-01

    As the use of X-ray tubes is widely spread mainly for medical diagnostic purposes or industrial applications, there is increasing demand for accurate and convenient way getting of X-ray beam spectral information. While measurement methods may provide quite accurate spectral information, these methods still require expensive detectors (example: HPGe, High Purity Germanium detector) and some conversion of measurement information into real spectrum. It is concluded that Laplace transform-based spectral reconstruction technique given in equations (1) and (2) works well for a 50-kV X-ray source. In this paper we obtained the attenuation curve by the use of MCNPX simulations. We were able to rebuild the X-ray spectrum of 50 kV through this research by Monte Carlo simulation (fitting parameters, a: 1.2921, b: 0.2342, ν: 0.6190, R-squared: 0.9930)

  12. Synchrotron X-ray micro-beam studies of ancient Egyptian make-up

    International Nuclear Information System (INIS)

    Martinetto, P.; Anne, M.; Dooryhee, E.; Drakopoulos, M.; Dubus, M.; Salomon, J.; Simionovici, A.; Walter, Ph.

    2001-01-01

    Vases full of make-up are most often present in the burial furniture of Egyptian tombs dated from the pharaonic period. The powdered cosmetics made of isolated grains are analysed to identify their trace element signature. From this signature we identify the provenance of the mineral ingredients in the make-up and we observe different impurities in products, which have been demonstrated as synthetic substances by previous works. Focused X-ray micro-beam (2x5 μm 2 ) is successively tuned at 11 keV, below the L III absorption edge of Pb, and 31.8 keV for global characterisation of the metal impurities. The fluorescence signal integrated over each single grain is detected against the X-ray micro-diffraction pattern collected in transmission with a bi-dimensional detector. Furthermore, for galena grains rich in Zn, the XANES signal at the K-absorption edge of Zn shows its immediate nearest-neighbour environment

  13. Synchrotron X-ray micro-beam studies of ancient Egyptian make-up

    Science.gov (United States)

    Martinetto, P.; Anne, M.; Dooryhée, E.; Drakopoulos, M.; Dubus, M.; Salomon, J.; Simionovici, A.; Walter, Ph.

    2001-07-01

    Vases full of make-up are most often present in the burial furniture of Egyptian tombs dated from the pharaonic period. The powdered cosmetics made of isolated grains are analysed to identify their trace element signature. From this signature we identify the provenance of the mineral ingredients in the make-up and we observe different impurities in products, which have been demonstrated as synthetic substances by previous works. Focused X-ray micro-beam ( 2×5 μm2) is successively tuned at 11 keV, below the L III absorption edge of Pb, and 31.8 keV for global characterisation of the metal impurities. The fluorescence signal integrated over each single grain is detected against the X-ray micro-diffraction pattern collected in transmission with a bi-dimensional detector. Furthermore, for galena grains rich in Zn, the XANES signal at the K-absorption edge of Zn shows its immediate nearest-neighbour environment.

  14. Synchrotron X-ray micro-beam studies of ancient Egyptian make-up

    Energy Technology Data Exchange (ETDEWEB)

    Martinetto, P; Anne, M; Dooryhee, E; Drakopoulos, M; Dubus, M; Salomon, J; Simionovici, A; Walter, Ph

    2001-07-01

    Vases full of make-up are most often present in the burial furniture of Egyptian tombs dated from the pharaonic period. The powdered cosmetics made of isolated grains are analysed to identify their trace element signature. From this signature we identify the provenance of the mineral ingredients in the make-up and we observe different impurities in products, which have been demonstrated as synthetic substances by previous works. Focused X-ray micro-beam (2x5 {mu}m{sup 2}) is successively tuned at 11 keV, below the L{sub III} absorption edge of Pb, and 31.8 keV for global characterisation of the metal impurities. The fluorescence signal integrated over each single grain is detected against the X-ray micro-diffraction pattern collected in transmission with a bi-dimensional detector. Furthermore, for galena grains rich in Zn, the XANES signal at the K-absorption edge of Zn shows its immediate nearest-neighbour environment.

  15. A new cone-beam X-ray CT system with a reduced size planar detector

    International Nuclear Information System (INIS)

    Li Liang; Chen Zhiqiang; Zhang Li; Xing Yuxiang; Kang Kejun

    2006-01-01

    In a traditional cone-beam CT system, the cost of product and computation is very high. The authors propose a transversely truncated cone-beam X-ray CT system with a reduced size detector positioned off-center, in which X-ray beams only cover half of the object. The reduced detector size cuts the cost and the X-ray dose of the CT system. The existing CT reconstruction algorithms are not directly applicable in this new CT system. Hence, the authors develop a BPF-type direct backprojection algorithm. Different from the traditional rebinding methods, our algorithm directly backprojects the pretreated projection data without rebinding. This makes the algorithm compact and computationally more efficient. Finally, some numerical simulations and practical experiments are done to validate the proposed algorithm. (authors)

  16. Deep reactive ion etching of silicon moulds for the fabrication of diamond x-ray focusing lenses

    Science.gov (United States)

    Malik, A. M.; Fox, O. J. L.; Alianelli, L.; Korsunsky, A. M.; Stevens, R.; Loader, I. M.; Wilson, M. C.; Pape, I.; Sawhney, K. J. S.; May, P. W.

    2013-12-01

    Diamond is a highly desirable material for use in x-ray optics and instrumentation. However, due to its extreme hardness and resistance to chemical attack, diamond is difficult to form into a structure suitable for x-ray lenses. Refractive lenses are capable of delivering x-ray beams with nanoscale resolution. A moulding technique for the fabrication of diamond lenses is reported. High-quality silicon moulds were made using photolithography and deep reactive ion etching. The study of the etch process conducted to achieve silicon moulds with vertical sidewalls and minimal surface roughness is discussed. Issues experienced when attempting to deposit diamond into a high-aspect-ratio mould by chemical vapour deposition are highlighted. Two generations of lenses have been successfully fabricated using this transfer-moulding approach with significant improvement in the quality and performance of the optics observed in the second iteration. Testing of the diamond x-ray optics on the Diamond Light Source Ltd synchrotron B16 beamline has yielded a line focus of sub-micrometre width.

  17. Neon dense plasma focus point x-ray source for ≤ 0.25 μm lithography

    International Nuclear Information System (INIS)

    Prasad, R.R.; Krishnan, M.; Berg, K.; Conlon, D.; Mangano, J.

    1994-01-01

    A discharge driven, dense plasma focus (DPF) in neon has been developed at SRL as a point x-ray source for sub-micron lithography. This source is presently capable of delivering ∼25 J/pulse of neon K-shell x-rays (8--14 angstrom) into 4 π steradians with a ∼1.4% wall plug efficiency at a 20 Hz repetition rate. The discharge is produced by a capacitor bank circuit (8 kV, 1.8 kJ) which has a fixed inductance of 11 nH and drives ∼ 320 kA currents into the DPF load, with ∼1 μs rise-times. X-rays are produced when a dense pinch of neon is formed along the axis of the DPF electrodes. The dense neon pinch has been found to be a cigar shaped object, ∼0.3 mm in diameter at the waist and ∼8 mm long on a singe shot. This source wanders slightly from shot to shot in an overall envelope which is ∼0.5--0.75 mm in diameter and ∼8 mm long. The spectrum of x-rays emitted by the pinch has been extensively studied. It has been found that 60% of the total x-ray output is radiated in the H-like and He-like lines centered at 12.9 angstrom and 40% of the output is radiated in the H-like and He-like continuum, centered at 9.8 angstrom. More than 4 x 10 5 discharges using a cooled DPF head have been fired producing x-rays. The variation in the measured x-ray output, over several hundreds of thousands of shots, corresponds to a variation in the dose delivered to a resist 40 cm from the source, of less than 1%. Data showing the measurement of the x-ray output, dose delivered to a resist, spectra of the source output, novel beam line concepts and potential lithographic applications will be presented

  18. Automated three-dimensional X-ray analysis using a dual-beam FIB

    International Nuclear Information System (INIS)

    Schaffer, Miroslava; Wagner, Julian; Schaffer, Bernhard; Schmied, Mario; Mulders, Hans

    2007-01-01

    We present a fully automated method for three-dimensional (3D) elemental analysis demonstrated using a ceramic sample of chemistry (Ca)MgTiO x . The specimen is serially sectioned by a focused ion beam (FIB) microscope, and energy-dispersive X-ray spectrometry (EDXS) is used for elemental analysis of each cross-section created. A 3D elemental model is reconstructed from the stack of two-dimensional (2D) data. This work concentrates on issues arising from process automation, the large sample volume of approximately 17x17x10 μm 3 , and the insulating nature of the specimen. A new routine for post-acquisition data correction of different drift effects is demonstrated. Furthermore, it is shown that EDXS data may be erroneous for specimens containing voids, and that back-scattered electron images have to be used to correct for these errors

  19. An X-ray beam position monitor based on the photoluminescence of helium gas

    Science.gov (United States)

    Revesz, Peter; White, Jeffrey A.

    2005-03-01

    A new method for white beam position monitoring for both bend magnet and wiggler synchrotron X-ray radiation has been developed. This method utilizes visible light luminescence generated as a result of ionization by the intense X-ray flux. In video beam position monitors (VBPMs), the luminescence of helium gas at atmospheric pressure is observed through a view port using a CCD camera next to the beam line. The beam position, profile, integrated intensity and FWHM are calculated from the distribution of luminescence intensity in each captured image by custom software. Misalignment of upstream apertures changes the image profile making VBPMs helpful for initial alignment of upstream beam line components. VBPMs can thus provide more information about the X-ray beam than most beam position monitors (BPMs). A beam position calibration procedure, employing a tilted plane-parallel glass plate placed in front of the camera lens, has also been developed. The accuracy of the VBPM system was measured during a bench-top experiment to be better than 1 μm. The He-luminescence-based VBPM system has been operative on three CHESS beam lines (F hard-bend and wiggler, A-line wiggler and G-line wiggler) for about a year. The beam positions are converted to analog voltages and used as feedback signals for beam stabilization. In our paper we discuss details of VBPM construction and describe further results of its performance.

  20. Investigation of chemical vapour deposition diamond detectors by X-ray micro-beam induced current and X-ray micro-beam induced luminescence techniques

    International Nuclear Information System (INIS)

    Olivero, P.; Manfredotti, C.; Vittone, E.; Fizzotti, F.; Paolini, C.; Lo Giudice, A.; Barrett, R.; Tucoulou, R.

    2004-01-01

    Tracking detectors have become an important ingredient in high-energy physics experiments. In order to survive the harsh detection environment of the large hadron collider (LHC), trackers need to have special properties. They must be radiation hard, provide fast collection of charge, be as thin as possible and remove heat from readout electronics. The unique properties of diamond allow it to fulfill these requirements. In this work we present an investigation of the charge transport and luminescence properties of 'detector grade' artificial chemical vapour deposition (CVD) diamond devices developed within the CERN RD42 collaboration, performed by means of X-ray micro-beam induced current collection (XBICC) and X-ray micro-beam induced luminescence (XBIL) techniques. XBICC technique allows quantitative estimates of the transport parameters of the material to be evaluated and mapped with micrometric spatial resolution. In particular, the high resolution and sensitivity of the technique has allowed a quantitative study of the inhomogeneity of the charge transport parameter defined as the product of mobility and lifetime for both electron and holes. XBIL represents a technique complementary to ion beam induced luminescence (IBIL), which has already been used by our group, since X-ray energy loss profile in the material is different from that of MeV ions. X-ray induced luminescence maps have been performed simultaneously with induced photocurrent maps, to correlate charge transport and induced luminescence properties of diamond. Simultaneous XBICC and XBIL maps exhibit features of partial complementarity that have been interpreted on the basis of considerations on radiative and non-radiative recombination processes which compete with charge transport efficiency

  1. X-ray diffraction and imaging with a coherent beam: application to X-ray optical elements and to crystals exhibiting phase inhomogeneities

    International Nuclear Information System (INIS)

    Masiello, F.

    2011-05-01

    The exceptional properties of synchrotron light sources have been exploited in very different disciplines, from archaeology to chemistry, from material science to biology, from medicine to physics. Among these properties it is important to mention the high brilliance, continuum spectrum, high degree of polarization, time structure, small source size and divergence of the beam, the last resulting in a high transversal coherence of the produced radiation. This high transversal coherence of the synchrotron sources has permitted the development of new techniques, e.g. phase contrast imaging, X-ray photon correlation spectroscopy and coherent X-ray diffraction imaging (CXDI). This thesis work will consist essentially of three parts. In the first part it will be presented the work done as a member of the X-ray Optics Group of ESRF in the characterization of high quality diamond crystals foreseen as X-ray optical elements. The characterization has been done using different complementary X-ray techniques, such as high resolution diffraction, topography, grazing incidence diffraction, reflectivity and measurements of the coherence preservation using the Talbot effect. In the second part, I will show the result obtained in the study of the temperature behaviours of the domain in periodically poled ferroelectrics crystals. This type of measurements, based on Bragg-Fresnel diffraction, are possible only thanks to the high degree of coherence of the beam. In the third part, I will present the results obtained in the characterization of diamonds foreseen for applications other than X-ray optical elements. (author)

  2. Cone beam x-ray luminescence computed tomography: a feasibility study.

    Science.gov (United States)

    Chen, Dongmei; Zhu, Shouping; Yi, Huangjian; Zhang, Xianghan; Chen, Duofang; Liang, Jimin; Tian, Jie

    2013-03-01

    The appearance of x-ray luminescence computed tomography (XLCT) opens new possibilities to perform molecular imaging by x ray. In the previous XLCT system, the sample was irradiated by a sequence of narrow x-ray beams and the x-ray luminescence was measured by a highly sensitive charge coupled device (CCD) camera. This resulted in a relatively long sampling time and relatively low utilization of the x-ray beam. In this paper, a novel cone beam x-ray luminescence computed tomography strategy is proposed, which can fully utilize the x-ray dose and shorten the scanning time. The imaging model and reconstruction method are described. The validity of the imaging strategy has been studied in this paper. In the cone beam XLCT system, the cone beam x ray was adopted to illuminate the sample and a highly sensitive CCD camera was utilized to acquire luminescent photons emitted from the sample. Photons scattering in biological tissues makes it an ill-posed problem to reconstruct the 3D distribution of the x-ray luminescent sample in the cone beam XLCT. In order to overcome this issue, the authors used the diffusion approximation model to describe the photon propagation in tissues, and employed the sparse regularization method for reconstruction. An incomplete variables truncated conjugate gradient method and permissible region strategy were used for reconstruction. Meanwhile, traditional x-ray CT imaging could also be performed in this system. The x-ray attenuation effect has been considered in their imaging model, which is helpful in improving the reconstruction accuracy. First, simulation experiments with cylinder phantoms were carried out to illustrate the validity of the proposed compensated method. The experimental results showed that the location error of the compensated algorithm was smaller than that of the uncompensated method. The permissible region strategy was applied and reduced the reconstruction error to less than 2 mm. The robustness and stability were then

  3. Providing Bright-Hard X-ray Beams from a Lower Energy Light Source

    Science.gov (United States)

    Robin, David

    2002-04-01

    At the Advanced Light Source (ALS) there had been an increasing demand for more high brightness harder X-ray sources in the 7 to 40 KeV range. In response to that demand, the ALS storage ring was modified in August 2001. Three 1.3 Tesla normal conducting bending magnets were removed and replaced with three 5 Tesla superconducting magnets (Superbends). The radiation produced by these Superbends is an order of magnitude higher in photon brightness and flux at 12 keV than the 1.3 Tesla bends, making them excellent sources of harder x-rays for protein crystallography and other harder x-ray applications. At the same time the Superbends do not compromise the performance of the facility in the UV and Soft X-ray regions of the spectrum. The Superbends will eventually feed 12 new x-ray beam lines greatly enhancing the facility's capacity in the hard x-ray region. The Superbend project is the biggest upgrade to the ALS storage ring since the ring was commissioned in 1993. In this paper we present, a history of the project, details of the magnet, installation, commissioning, and resulting performance of the ALS with Superbends.

  4. Assessment of image quality in x-ray radiography imaging using a small plasma focus device

    International Nuclear Information System (INIS)

    Kanani, A.; Shirani, B.; Jabbari, I.; Mokhtari, J.

    2014-01-01

    This paper offers a comprehensive investigation of image quality parameters for a small plasma focus as a pulsed hard x-ray source for radiography applications. A set of images were captured from some metal objects and electronic circuits using a low energy plasma focus at different voltages of capacitor bank and different pressures of argon gas. The x-ray source focal spot of this device was obtained to be about 0.6 mm using the penumbra imaging method. The image quality was studied by several parameters such as image contrast, line spread function (LSF) and modulation transfer function (MTF). Results showed that the contrast changes by variations in gas pressure. The best contrast was obtained at a pressure of 0.5 mbar and 3.75 kJ stored energy. The results of x-ray dose from the device showed that about 0.6 mGy is sufficient to obtain acceptable images on the film. The measurements of LSF and MTF parameters were carried out by means of a thin stainless steel wire 0.8 mm in diameter and the cut-off frequency was obtained to be about 1.5 cycles/mm. - Highlights: • We investigated a small plasma focus as pulsed x-ray source for radiography applications. • The image quality was studied by several parameters such as image contrast, LSF and MTF. • The x-ray source focal spot was obtained to be ∼0.6 mm using the penumbra imaging method. • The x-ray dose measurement showed that about 0.6 mGy is sufficient to obtain acceptable images on the film. • The profiles of LSF and MTF showed that the cut-off frequency is about 1.5 cycles/mm

  5. A Study on Mono-energetic Beam Source Using Characteristic X-ray for Substance Identification System

    International Nuclear Information System (INIS)

    Lee, Hwan Soo

    2009-02-01

    A new mono-energetic beam source was developed by using characteristic X-ray for improving performance of the substance identification system. Most of inspection systems use X-ray tubes for their source modules. However, the broad energy spectrum of X-ray tube causes an increase of uncertainty. In this study, it was found that mono-energetic beam sources can be generated by using X-ray tube and the designed target filter assembly. In order to investigate the monoenergetic beam source, the sensitivity study was conducted with a series of different X-ray tube potentials, radiator and filter materials using Monte Carlo simulation. The developed beam sources have a mono-energy peak at 69 keV, 78 keV and 99 keV, and they are named as characteristic X-ray beam BEAM69, BEAM78 and BEAM99, respectively. The characteristic X-ray beam intensity was over thirty three times more than that of hardening beam used previous work at Hanyang University. And BEAM69 and BEAM99 were applied to the substance identification system as a source. The relative error between results of characteristic X-ray beams and 69 keV and 99 keV photons was about 2% on the average for five unknown materials. In comparison with experiment results by using hardening beam, characteristic X-ray beam achieves better accuracy which is about 6.46 % on the average. Hence, it is expected that the developed characteristic X-ray beam source helps lower uncertainty of the inspection system, and the inspection time will be reduced considerably due to its high beam intensity

  6. Characteristics of x-rays from a plasma focus operated with neon gas

    Energy Technology Data Exchange (ETDEWEB)

    Zakaullah, M [Department of Physics, Quaid-i-Azam University, 45320 Islamabad (Pakistan); Alamgir, K [Department of Physics, Quaid-i-Azam University, 45320 Islamabad (Pakistan); Shafiq, M [Department of Physics, Quaid-i-Azam University, 45320 Islamabad (Pakistan); Hassan, S M [Department of Physics, Quaid-i-Azam University, 45320 Islamabad (Pakistan); Sharif, M [Department of Physics, Quaid-i-Azam University, 45320 Islamabad (Pakistan); Hussain, S [Department of Physics, Quaid-i-Azam University, 45320 Islamabad (Pakistan); Waheed, A [PINSTECH, PO Box 2151, 44000 Islamabad (Pakistan)

    2002-11-01

    The x-ray emission from a low-energy (2.3 kJ) plasma focus is investigated with neon as the filling gas. Two anode configurations are used in the experiment: the conventional cylindrical anode, and tapered anode slightly toward the open end. The latter geometry enhances soft x-ray emission by an order of magnitude. The emission is pressure dependent and, in both cases, the highest emission is observed at 3-3.5 mbar. For the cylindrical anode, the soft x-ray emission is up to 7 J per shot, which is from a pinched plasma column, 5-6 mm long. For the tapered anode, up to 80 J per shot soft x-ray yield in 4{pi} geometry is recorded, which corresponds to 4% wall plug efficiency. The diameter of the x-ray emission filament is much larger compared with the cylindrical anode. The bulk of emitted radiation is of energy 1.2-1.3 keV, which is thought to arise from recombination of hydrogen-like (Ne x) ions with the low-energy electrons.

  7. Characteristics of x-rays from a plasma focus operated with neon gas

    International Nuclear Information System (INIS)

    Zakaullah, M; Alamgir, K; Shafiq, M; Hassan, S M; Sharif, M; Hussain, S; Waheed, A

    2002-01-01

    The x-ray emission from a low-energy (2.3 kJ) plasma focus is investigated with neon as the filling gas. Two anode configurations are used in the experiment: the conventional cylindrical anode, and tapered anode slightly toward the open end. The latter geometry enhances soft x-ray emission by an order of magnitude. The emission is pressure dependent and, in both cases, the highest emission is observed at 3-3.5 mbar. For the cylindrical anode, the soft x-ray emission is up to 7 J per shot, which is from a pinched plasma column, 5-6 mm long. For the tapered anode, up to 80 J per shot soft x-ray yield in 4π geometry is recorded, which corresponds to 4% wall plug efficiency. The diameter of the x-ray emission filament is much larger compared with the cylindrical anode. The bulk of emitted radiation is of energy 1.2-1.3 keV, which is thought to arise from recombination of hydrogen-like (Ne x) ions with the low-energy electrons

  8. Spectroscopic analysis and dosimetry of diagnostic x-ray beams filtered by rare earth materials

    International Nuclear Information System (INIS)

    Tyndall, D.A.

    1986-01-01

    A laboratory investigation was carried out to assess the effect of various types of rare earth filter materials on the energy spectrum and concomitant reduced exposure values of diagnostic x-ray beams at 70, 80, and 90 kVp. An x-ray spectroscope was constructed and used to generate the energy spectra of beams passing through the various rare earth filter materials. Photographs were made of each spectrum, and live-time gross photon counts were recorded. Following spectral determinations, ionization chamber readings were generated for each filter material. Substantial effects on x-ray spectra and reduction of exposure values were noted. The degree of these effects were dependent on the atomic number, k-edge, and thickness of each filter. Metallic forms of rare earth materials proved to be more effective than the salt forms with erbium offering the greatest potential for reduction in exposures over the range of experimental kilovolt (peak) values

  9. Simulations of X-ray synchrotron beams using the EGS4 code system in medical applications

    International Nuclear Information System (INIS)

    Orion, I.; Henn, A.; Sagi, I.; Dilmanian, F.A.; Pena, L.; Rosenfeld, A.B.

    2001-01-01

    X-ray synchrotron beams are commonly used in biological and medical research. The availability of intense, polarized low-energy photons from the synchrotron beams provides a high dose transfer to biological materials. The EGS4 code system, which includes the photoelectron angular distribution, electron motion inside a magnetic field, and the LSCAT package, found to be the appropriate Monte Carlo code for synchrotron-produced X-ray simulations. The LSCAT package was developed in 1995 for the EGS4 code to contain the routines to simulate the linear polarization, the bound Compton, and the incoherent scattering functions. Three medical applications were demonstrated using the EGS4 Monte Carlo code as a proficient simulation code system for the synchrotron low-energy X-ray source. (orig.)

  10. Diamond monochromator for high heat flux synchrotron x-ray beams

    International Nuclear Information System (INIS)

    Khounsary, A.M.; Smither, R.K.; Davey, S.; Purohit, A.

    1992-12-01

    Single crystal silicon has been the material of choice for x-ray monochromators for the past several decades. However, the need for suitable monochromators to handle the high heat load of the next generation synchrotron x-ray beams on the one hand and the rapid and on-going advances in synthetic diamond technology on the other make a compelling case for the consideration of a diamond mollochromator system. In this Paper, we consider various aspects, advantage and disadvantages, and promises and pitfalls of such a system and evaluate the comparative an monochromator subjected to the high heat load of the most powerful x-ray beam that will become available in the next few years. The results of experiments performed to evaluate the diffraction properties of a currently available synthetic single crystal diamond are also presented. Fabrication of diamond-based monochromator is within present technical means

  11. Improvements in Off-Center Focusing in an X-ray Streak Camera

    International Nuclear Information System (INIS)

    McDonald, J W; Weber, F; Holder, J P; Bell, P M

    2003-01-01

    Due to the planar construction of present x-ray streak tubes significant off-center defocusing is observed in both static and dynamic images taken with one-dimensional resolution slits. Based on the streak tube geometry curved photocathodes with radii of curvature ranging from 3.5 to 18 inches have been fabricated. We report initial off-center focusing performance data on the evaluation of these ''improved'' photocathodes in an X-ray streak camera and an update on the theoretical simulations to predict the optimum cathode curvature

  12. X-ray beam splitting design for concurrent imaging at hard X-ray FELs and synchrotron facilities

    Czech Academy of Sciences Publication Activity Database

    Oberta, Peter; Mokso, R.

    2013-01-01

    Roč. 729, NOV (2013), s. 85-89 ISSN 0168-9002 R&D Projects: GA MPO FR-TI1/412 Institutional research plan: CEZ:AV0Z10100522 Keywords : diffractive-refractive optics * hard X-ray FEL * X-ray imaging Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.316, year: 2013 http://www.sciencedirect.com/science/article/pii/S0168900213009613

  13. Energy dependence evaluation of a ZnO detector for diagnostic X-ray beam

    International Nuclear Information System (INIS)

    Valença, C.P.V.; Silveira, M.A.L.; Macedo, M.A.; Santos, M.A.

    2015-01-01

    In the last decades the international organizations of human health and radiation protection have recommended certain care for using X-ray as a diagnosis tool. The current concern is to avoid any type of radiological accident or overdose to the patient. This can be done assessing the parameters of the X-ray equipment and there are various types of detectors available for that: ionizing chamber, semiconductor devices, etc. These detectors must be calibrated so that they can be used for any energy range and such a procedure is correlated with what is called the energy dependence of the detector. In accordance with the stated requirements of IEC 61267, the standard radiation quality beams and irradiation conditions (RQRs) are the tools and techniques for calibrating diagnostic X-Ray instruments and detectors. The purpose of this work is to evaluate the behavior of the energy dependence of a detector fabricated from a zinc oxide (ZnO) nanofilm. A Pantak industrial X-ray equipment was used to generate the RQR radiation quality beams and test three ZnO detector samples. A 6430 sub-femto-ammeter, Keithley, was used to bias the ZnO detector and simultaneously perform the output readings. The results showed that the ZnO device has some increase in its sensitivity to the ionizing radiation as the X-ray effective energy decreases unlike other types of semiconductor electronic devices typically used as an X-ray detector. We can be concluded that, after calibration, the ZnO device can be used as a diagnostic X-ray detector. (author)

  14. The Focusing Optics X-ray Solar Imager (FOXSI) SMEX Mission

    Science.gov (United States)

    Christe, S.; Shih, A. Y.; Krucker, S.; Glesener, L.; Saint-Hilaire, P.; Caspi, A.; Allred, J. C.; Battaglia, M.; Chen, B.; Drake, J. F.; Gary, D. E.; Goetz, K.; Gburek, S.; Grefenstette, B.; Hannah, I. G.; Holman, G.; Hudson, H. S.; Inglis, A. R.; Ireland, J.; Ishikawa, S. N.; Klimchuk, J. A.; Kontar, E.; Kowalski, A. F.; Massone, A. M.; Piana, M.; Ramsey, B.; Schwartz, R.; Steslicki, M.; Turin, P.; Ryan, D.; Warmuth, A.; Veronig, A.; Vilmer, N.; White, S. M.; Woods, T. N.

    2017-12-01

    We present FOXSI (Focusing Optics X-ray Solar Imager), a Small Explorer (SMEX) Heliophysics mission that is currently undergoing a Phase A concept study. FOXSI will provide a revolutionary new perspective on energy release and particle acceleration on the Sun. FOXSI is a direct imaging X-ray spectrometer with higher dynamic range and better than 10x the sensitivity of previous instruments. Flown on a 3-axis-stabilized spacecraft in low-Earth orbit, FOXSI uses high-angular-resolution grazing-incidence focusing optics combined with state-of-the-art pixelated solid-state detectors to provide direct imaging of solar hard X-rays for the first time. FOXSI is composed of a pair of x-ray telescopes with a 14-meter focal length enabled by a deployable boom. Making use of a filter-wheel and high-rate-capable solid-state detectors, FOXSI will be able to observe the largest flares without saturation while still maintaining the sensitivity to detect x-ray emission from weak flares, escaping electrons, and hot active regions. This mission concept is made possible by past experience with similar instruments on two FOXSI sounding rocket flights, in 2012 and 2014, and on the HEROES balloon flight in 2013. FOXSI's hard X-ray imager has a field of view of 9 arcminutes and an angular resolution of better than 8 arcsec; it will cover the energy range from 3 up to 50-70 keV with a spectral resolution of better than 1 keV; and it will have sub-second temporal resolution.

  15. Dynamics of hot spots in the DPF-78 plasma focus from x-ray spectra and REB emission

    International Nuclear Information System (INIS)

    Schmidt, H.; Wang, X.X.

    1995-01-01

    The X-ray emission from hot spots in the plasma focus DPF-78 was investigated with the help of two X-ray quartz crystal spectrometers of the Johann type and a 4 fold magnifying X-ray pinhole camera. In the experiments the working gas was chosen to be 300 Pa deuterium with 20 Pa argon admixture. X-ray spectra in the wavelength range from 3.55 angstrom to 4.0 angstrom, including H-like and He-like Argon lines, were recorded on Kodak DEF-2 film. From the spatially resolved spectra recorded side-on, a relative spectral shift between different hot spots of the same shot was often observed. The shift could be attributed to the Doppler shift. From spectral characteristics such as intensities and FWHM of Ar resonant and intercombination lines electron densities of up to 3 x 10 27 m -3 were determined. Radial dimensions of the hot spots ranging from about 140 microm to 300 microm were found from pinhole pictures applying the penumbra method. Usually two pulses of relativistic electron beams were observed using Cherenkov detectors in a magnetic spectrometer. The energy of the first pulse, which was emitted at the time of maximum compression, was higher than that of the second pulse. The measured FWHM of the REB pulses ranges from 3 ns to about 10 ns. The characteristics of the time-integrated X-ray spectra and the time resolved REB spectra and their dependence on the composition of the filling gas are discussed

  16. The importance of the right focusing technique. At-a-glance information on focusing techniques in X-ray procedures

    International Nuclear Information System (INIS)

    Lichte-Wichmann, M.

    1993-01-01

    Sharp pictures providing all the information relevant to a particular case obviate repeat exposures, help to keep the radiation dose to a minimum and prevent false diagnoses. In her book, the author gives practical guidance on focusing techniques that is equally valuable to beginners and experienced investigators or medical X-ray assistants and physicians. A substantial part of the book is devoted to detailed instructions on how an object is brought into focus as well as on the criteria of proper focusing and the possibilities of identifying and avoiding false focusing techniques. The problems arising when uncommon X-ray pictures have to be taken are explained by diagrammatic representations. (orig.) [de

  17. Space-time structure of neutron and X-ray sources in a plasma focus

    International Nuclear Information System (INIS)

    Bostick, W.H.; Nardi, V.; Prior, W.

    1977-01-01

    Systematic measurements with paraffin collimators of the neutron emission intensity have been completed on a plasma focus with a 15-20 kV capacitor bank (hollow centre electrode; discharge period T approximately 8 μs; D 2 filling at 4-8 torr). The space resolution was 1 cm or better. These data indicate that at least 70% of the total neutron yield originates within hot-plasma regions where electron beams and high-energy D beams (approximately > 0.1-1 MeV) are produced. The neutron source is composed of several (approximately > 1-10) space-localized sources of different intensity, each with a duration approximately less than 5 ns (FWHM). Localized neutron sources and hard (approximately > 100 keV) X-ray sources have the same time multiplicity and are usually distributed in two groups over a time interval 40-400 ns long. By the mode of operation used by the authors one group of localized sources (Burst II) is observed 200-400 ns after the other group (Burst I) and its space distribution is broader than for Burst I. The maximum intensity of a localized source of neutrons in Burst I is much higher than the maximum intensity in Burst II. Secondary reactions T(D,n) 4 He (from the tritium produced only by primary reactions in the same discharge; no tritium was used in filling the discharge chamber) are observed in a time coincidence with the strongest D-D neutron pulse of Burst I. The neutron signal from a localized source with high intensity has a relatively long tail of small amplitude (area tail approximately less than 0.2 X area peak). This tail can be generated by the D-D reactions of the unconfined part of an ion beam in the cold plasma. Complete elimination of scattered neutrons on the detector was achieved in these measurements. (author)

  18. Dosimetry and narrow X-ray beams, produced by particle linear accelerator for use in radiosurgery

    International Nuclear Information System (INIS)

    Campos, J.C.F.; Vizeu, D.M.

    1987-01-01

    The principal characteristics of dosimetry and narrow X-ray beams(4Mv) monitoring are investigated for use in estereotatic radiosurgery. An additional collimator system and a estereotatic system (Leksell type) are presented. Dosimetric parameters like tissue-air ratio, peak scatter factor, isodose curves are studied. (M.A.C.) [pt

  19. X-ray spectroscopy of highly-ionized atoms in an electron beam ion trap (EBIT)

    International Nuclear Information System (INIS)

    Marrs, R.E.; Bennett, C.; Chen, M.H.

    1988-01-01

    An Electron Beam Ion Trap at Lawrence Livermore National Laboratory is being used to produce and trap very-highly-charged-ions (q /le/ 70+) for x-ray spectroscopy measurements. Recent measurements of dielectronic recombination, electron impact excitation and transition energies are presented. 15 refs., 12 figs., 1 tab

  20. X-ray spectra from the Cornell Electron-Beam Ion Source (CEBIS I)

    International Nuclear Information System (INIS)

    Johnson, B.M.; Jones, K.W.; Kostroun, V.O.; Ghanbari, E.; Janson, S.W.

    1985-01-01

    Radiation emitted from the Cornell electron beam ion source (CEBIS I) has been surveyed with a Si(Li) x-ray detector. These spectra can be used to estimate backgrounds from electron bremsstrahlung and to evaluate the feasibility of atomic physics experiments using the CEBIS I source in this configuration. 1 ref., 2 figs

  1. Electron beam requirements for soft x-ray/XUV free-electron lasers

    International Nuclear Information System (INIS)

    Goldstein, J.C.

    1987-01-01

    A discussion of the electron beam quality (peak current, energy spread, and transverse emittance) required to drive short wavelength free-electron lasers in the XUV (10-100 nm) and soft x-ray (<10 nm) optical wavelength ranges is presented

  2. X-ray Radiation Mechanisms and the Beaming Effect of Hot Spots ...

    Indian Academy of Sciences (India)

    Astr. (2011) 32, 193–196 c Indian Academy of Sciences. X-ray Radiation Mechanisms and the Beaming Effect of Hot Spots and Knots in AGN Jets. Jin Zhang1,∗. , Jin-Ming Bai2, Liang Chen2 & Enwei Liang3. 1College of Physics and Electronic Engineering, Guangxi Teachers Education University,. Nanning 530001, China.

  3. Cone Beam X-ray Luminescence Computed Tomography Based on Bayesian Method.

    Science.gov (United States)

    Zhang, Guanglei; Liu, Fei; Liu, Jie; Luo, Jianwen; Xie, Yaoqin; Bai, Jing; Xing, Lei

    2017-01-01

    X-ray luminescence computed tomography (XLCT), which aims to achieve molecular and functional imaging by X-rays, has recently been proposed as a new imaging modality. Combining the principles of X-ray excitation of luminescence-based probes and optical signal detection, XLCT naturally fuses functional and anatomical images and provides complementary information for a wide range of applications in biomedical research. In order to improve the data acquisition efficiency of previously developed narrow-beam XLCT, a cone beam XLCT (CB-XLCT) mode is adopted here to take advantage of the useful geometric features of cone beam excitation. Practically, a major hurdle in using cone beam X-ray for XLCT is that the inverse problem here is seriously ill-conditioned, hindering us to achieve good image quality. In this paper, we propose a novel Bayesian method to tackle the bottleneck in CB-XLCT reconstruction. The method utilizes a local regularization strategy based on Gaussian Markov random field to mitigate the ill-conditioness of CB-XLCT. An alternating optimization scheme is then used to automatically calculate all the unknown hyperparameters while an iterative coordinate descent algorithm is adopted to reconstruct the image with a voxel-based closed-form solution. Results of numerical simulations and mouse experiments show that the self-adaptive Bayesian method significantly improves the CB-XLCT image quality as compared with conventional methods.

  4. Half value layer determination of Al and Cu for different x-ray beams and establishing a relationship between them

    International Nuclear Information System (INIS)

    Kharita, M. H.; Takeyeddin, M.; Wali, K.; Zahili, M.

    2005-03-01

    The Half Value Layer (HVL) of copper and aluminium for special standard x-rays beams (emitted from x-ray machine type Philips MGC30 used in Secondary Standard Dosimetry Laboratory (SSDL) have been determined. The relationship between HVL values of aluminium and copper was established. This relationship can be represented by a non-linear fit. These results are valuable for x-ray workers especially those working in the field of radiation calibration for beam energy determination. Using the results of this study, unavailable thickness of one metal can be replaced by the corresponding thickness of the other metal, for filtration and measurement of x-ray beam. (Authors)

  5. Study of hard braking x-ray radiation on the radiation-beam complex ''TEMP''

    International Nuclear Information System (INIS)

    Batrakov, A.B.; Glushko, E.G.; Egorov, A.M.; Zinchenko, A.A.; Litvinenko, V.V.; Lonin, Yu.F.; Ponomarev, A.G.; Rybka, A.V.; Fedotov, S.I.; Uvarov, V.T.

    2015-01-01

    A calculation over of basic parameters of the hard brake x-rayed radiation for the microsecond accelerating of relativistic electronic beam T EMP . Optimization of converters is conducted for these aims. Maximal doses are experimentally got brake x-rayed radiation on beam-radiation complex T EMP . The diagrams of orientation of the brake x-rayed radiation are taken off depending on energies of bunches and forms of electrodes.

  6. X-ray section topographs under various coherence properties of the primary beam

    International Nuclear Information System (INIS)

    Borowski, J.; Gronkowski, J.

    2001-01-01

    The aim of this work is to study to what extent a typical section-topography setup can supply information about the degree of coherence of the incident x-ray beam. In real experiments, the incident beam is partially coherent, with the degree of coherence described by the shape of the correlation function. In this paper the correlation functions for the outgoing beam are calculated by solving the Takagi-Taupin equations, assuming a truncated Gauss correlation function for the incident beam with the correlation length determined by the van Cittert-Zernike theorem. Its influence on the measured intensity of the diffracted beam in section topography is investigated. (author)

  7. 3D algebraic iterative reconstruction for cone-beam x-ray differential phase-contrast computed tomography.

    Science.gov (United States)

    Fu, Jian; Hu, Xinhua; Velroyen, Astrid; Bech, Martin; Jiang, Ming; Pfeiffer, Franz

    2015-01-01

    Due to the potential of compact imaging systems with magnified spatial resolution and contrast, cone-beam x-ray differential phase-contrast computed tomography (DPC-CT) has attracted significant interest. The current proposed FDK reconstruction algorithm with the Hilbert imaginary filter will induce severe cone-beam artifacts when the cone-beam angle becomes large. In this paper, we propose an algebraic iterative reconstruction (AIR) method for cone-beam DPC-CT and report its experiment results. This approach considers the reconstruction process as the optimization of a discrete representation of the object function to satisfy a system of equations that describes the cone-beam DPC-CT imaging modality. Unlike the conventional iterative algorithms for absorption-based CT, it involves the derivative operation to the forward projections of the reconstructed intermediate image to take into account the differential nature of the DPC projections. This method is based on the algebraic reconstruction technique, reconstructs the image ray by ray, and is expected to provide better derivative estimates in iterations. This work comprises a numerical study of the algorithm and its experimental verification using a dataset measured with a three-grating interferometer and a mini-focus x-ray tube source. It is shown that the proposed method can reduce the cone-beam artifacts and performs better than FDK under large cone-beam angles. This algorithm is of interest for future cone-beam DPC-CT applications.

  8. Development of high-resolution x-ray CT system using parallel beam geometry

    Energy Technology Data Exchange (ETDEWEB)

    Yoneyama, Akio, E-mail: akio.yoneyama.bu@hitachi.com; Baba, Rika [Central Research Laboratory, Hitachi Ltd., Hatoyama, Saitama (Japan); Hyodo, Kazuyuki [Institute of Materials Science, High Energy Accelerator Research Organization, Tsukuba, Ibaraki (Japan); Takeda, Tohoru [School of Allied Health Sciences, Kitasato University, Sagamihara, Kanagawa (Japan); Nakano, Haruhisa; Maki, Koutaro [Department of Orthodontics, School of Dentistry Showa University, Ota-ku, Tokyo (Japan); Sumitani, Kazushi; Hirai, Yasuharu [Kyushu Synchrotron Light Research Center, Tosu, Saga (Japan)

    2016-01-28

    For fine three-dimensional observations of large biomedical and organic material samples, we developed a high-resolution X-ray CT system. The system consists of a sample positioner, a 5-μm scintillator, microscopy lenses, and a water-cooled sCMOS detector. Parallel beam geometry was adopted to attain a field of view of a few mm square. A fine three-dimensional image of birch branch was obtained using a 9-keV X-ray at BL16XU of SPring-8 in Japan. The spatial resolution estimated from the line profile of a sectional image was about 3 μm.

  9. Development of isodose curves for A 6 mv x-ray beam

    International Nuclear Information System (INIS)

    Hidaytalla, Lamya Abbas

    1994-08-01

    In this thesis radiation distribution of 6 Mv x-ray beam in a water phantom is developed. The method is based on a simple empirical equation and the assumption that the x-ray source is a point source. This leads to a simple equation for the calculation and plotting of the isodose curves. the charts obtained for two fields, 6*6 and 12*12 cm 2 show good agreement with the previous data used in the isotope and radiation centre, Khartoum hospital. It is suggested that further development should be carried out by writing a computer program for all the fields. (Author)

  10. Development, Beam characterization and chromosomal effectiveness of X-rays of RBC characteristic X-ray generator

    International Nuclear Information System (INIS)

    Endo, Satoru; Hoshi, Masaharu; Takada, Jun; Takatsuji, Toshihiro; Ejima, Yosuke; Saigusa, Shin; Tachibana, Akira; Sasaki, Masao S.

    2006-01-01

    A characteristic hot-filament type X-ray generator was constructed for irradiation of cultured cells. The source provides copper K, iron K, chromium K, molybdenum L, aluminium K and carbon K shell characteristic X-rays. When cultured mouse m5S cells were irradiated and frequencies of dicentrics were fitted to a linear-quadratic model, Y=αD+βD 2 , the chromosomal effectiveness was not a simple function of photon energy. The α-terms increased with the decrease of the photon energy and then decreased with further decrease of the energy with an inflection point at around 10 keV. The β-terms stayed constant for the photon energy down to 10 keV and then increased with further decrease of energy. Below 10 keV, the relative biological effectiveness (RBE) at low doses was proportional to the photon energy, which contrasted to that for high energy X- or γ-rays where the RBE was inversely related with the photon energy. The reversion of the energy dependency occurred at around 1-2 Gy, where the RBE of soft X-rays was insensitive to X-ray energy. The reversion of energy-RBE relation at a moderate dose may shed light on the controversy on energy dependency of RBE of ultrasoft X-rays in cell survival experiments. (author)

  11. A beam intensity monitor for the evaluation beamline for soft x-ray optical elements

    International Nuclear Information System (INIS)

    Imazono, Takashi; Moriya, Naoji; Harada, Yoshihisa; Sano, Kazuo; Koike, Masato

    2012-01-01

    Evaluation Beamline for Soft X-Ray Optical Elements (BL-11) at the SR Center of Ritsumeikan University has been operated to measure the wavelength and angular characteristics of soft x-ray optical components in a wavelength range of 0.65-25 nm using a reflecto-diffractometer (RD). The beam intensity monitor that has been equipped in BL-11 has observed the signal of the zero-th order light. For the purpose of more accurate evaluation of the performance of optical components, a new beam intensity monitor to measure the intensity of the first order light from the monochromator in BL-11 has been developed and installed in just front of RD. The strong positive correlation between the signal of the beam monitor and a detector equipped in the RD is shown. It is successful that the beam intensity of the first order light can be monitored in real time.

  12. Fabrication of the multilayer beam splitters with large area for soft X-ray laser interferometer

    International Nuclear Information System (INIS)

    Wang Zhanshan; Zhang Zhong; Wang Fengli; Wu Wenjuan; Wang Hongchang; Qin Shuji; Chen Lingyan

    2004-01-01

    The soft X-ray laser Mach-Zehnder interferometer is an important tool to measure the electron densities of a laser-produced plasma near the critical surface. The design of a multilayer beam splitter at 13.9 nm for soft X-ray laser Mach-Zehnder interferometer is completed based on the standard of maximizing product of reflectivity and transmission of the beam splitter. The beam splitters which is Mo/Si multilayers on 10 mm x 10 mm area Si 3 N 4 membrane are fabricated using the magnetron sputtering. The figure error of the beam splitter has reached the deep nanometer magnitude by using optical profiler and the product of reflectivity and transmission measured by synchrotron radiation is up to to 4%. (authors)

  13. Dense plasma focus x-ray source for sub-micron lithography

    International Nuclear Information System (INIS)

    Prasad, R.R.; Krishnan, M.; Mangano, J.; Greene, P.; Qi, Niansheng

    1993-01-01

    A discharge driven, dense plasma focus in neon is under development at SRL for use as a point x-ray source for sub-micron lithography. This source is presently capable of delivering ∼ 13j/pulse of neon K-shell x-rays (8--14 angstrom) into 4π steradians with 2 kj of electrical energy stored in the capacitor bank charged to 9 kV at a pulse repetition rate of 2 Hz. The discharge is produced by a ≤4 kj, ≤12 kV, capacitor bank circuit, which has a fixed inductance of 12 nH and drives ≤450 kA currents into the DPF load, with ∼1.1 μs rise-times. X-rays are produced when a dense pinch of neon is formed along the axis of the DPF electrodes. A new rail-gap switched capacitor bank and DPF have been built, designed for continuous operation at 2 Hz and burst mode operation at 20 Hz. This paper will present measurements of the x-ray output at a repetition rate of 2 Hz using the new capacitor bank. It will also describe measurements of the spot size (0.3--0.8 mm) and the spectrum (8--14 angstrom) of the DPF source. The dependence of these parameters on the DPF head geometry, bank energy and operating pressure will be discussed. The x-ray output has been measured using filtered pin diodes, x-ray diodes, and absolutely calibrated x-ray crystal spectra. Results from the source operating at 2 Hz will be presented. A novel concept of a windowless beamline has also been developed. The results of preliminary experiments to test the concept will be discussed. At a pulse repetition rate of 20 Hz, this source should produce 200--400 W of x-ray power in the 8-14 angstrom wavelength band, with an input power of 40--60 kW

  14. Dose properties of x-ray beams produced by laser-wakefield-accelerated electrons

    International Nuclear Information System (INIS)

    Kainz, K K; Hogstrom, K R; Antolak, J A; Almond, P R; Bloch, C D

    2005-01-01

    Given that laser wakefield acceleration (LWFA) has been demonstrated experimentally to accelerate electron beams to energies beyond 25 MeV, it is reasonable to assess the ability of existing LWFA technology to compete with conventional radiofrequency linear accelerators in producing electron and x-ray beams for external-beam radiotherapy. We present calculations of the dose distributions (off-axis dose profiles and central-axis depth dose) and dose rates of x-ray beams that can be produced from electron beams that are generated using state-of-the-art LWFA. Subsets of an LWFA electron energy distribution were propagated through the treatment head elements (presuming an existing design for an x-ray production target and flattening filter) implemented within the EGSnrc Monte Carlo code. Three x-ray energy configurations (6 MV, 10 MV and 18 MV) were studied, and the energy width ΔE of the electron-beam subsets varied from 0.5 MeV to 12.5 MeV. As ΔE increased from 0.5 MeV to 4.5 MeV, we found that the off-axis and central-axis dose profiles for x-rays were minimally affected (to within about 3%), a result slightly different from prior calculations of electron beams broadened by scattering foils. For ΔE of the order of 12 MeV, the effect on the off-axis profile was of the order of 10%, but the central-axis depth dose was affected by less than 2% for depths in excess of about 5 cm beyond d max . Although increasing ΔE beyond 6.5 MeV increased the dose rate at d max by more than 10 times, the absolute dose rates were about 3 orders of magnitude below those observed for LWFA-based electron beams at comparable energies. For a practical LWFA-based x-ray device, the beam current must be increased by about 4-5 orders of magnitude. (note)

  15. FIRST IMAGES FROM THE FOCUSING OPTICS X-RAY SOLAR IMAGER

    Energy Technology Data Exchange (ETDEWEB)

    Krucker, Säm; Glesener, Lindsay; Turin, Paul; McBride, Stephen; Glaser, David; Fermin, Jose; Lin, Robert [Space Sciences Laboratory, University of California at Berkeley, Berkeley, CA (United States); Christe, Steven [NASA Goddard Space Flight Center, Greenbelt, MD (United States); Ishikawa, Shin-nosuke [National Astronomical Observatory, Mitaka (Japan); Ramsey, Brian; Gubarev, Mikhail; Kilaru, Kiranmayee [NASA Marshall Space Flight Center, Huntsville, AL (United States); Takahashi, Tadayuki; Watanabe, Shin; Saito, Shinya [Institute of Space and Astronautical Science (ISAS)/JAXA, Sagamihara (Japan); Tajima, Hiroyasu [Solar-Terrestial Environment Laboratory, Nagoya University, Nagoya (Japan); Tanaka, Takaaki [Department of Physics, Kyoto University, Kyoto (Japan); White, Stephen [Air Force Research Laboratory, Albuquerque, NM (United States)

    2014-10-01

    The Focusing Optics X-ray Solar Imager (FOXSI) sounding rocket payload flew for the first time on 2012 November 2, producing the first focused images of the Sun above 5 keV. To enable hard X-ray (HXR) imaging spectroscopy via direct focusing, FOXSI makes use of grazing-incidence replicated optics combined with fine-pitch solid-state detectors. On its first flight, FOXSI observed several targets that included active regions, the quiet Sun, and a GOES-class B2.7 microflare. This Letter provides an introduction to the FOXSI instrument and presents its first solar image. These data demonstrate the superiority in sensitivity and dynamic range that is achievable with a direct HXR imager with respect to previous, indirect imaging methods, and illustrate the technological readiness for a spaceborne mission to observe HXRs from solar flares via direct focusing optics.

  16. Generalized algorithm for X-ray projections generation in cone-beam tomography

    International Nuclear Information System (INIS)

    Qin Zhongyuan; Mu Xuanqin; Wang Ping; Cai Yuanlong; Hou Chuanjian

    2002-01-01

    In order to get rid of random factors in the measurement so as to support proceeding 3D reconstruction, a general approach is presented to obtain the X-ray projections in cone-beam tomography. The phantom is firstly discretized into cubic volume through inverse transformation then a generalized projection procedure is proposed to the digitized result without concerning what the phantom exactly is. In the second step, line integrals are calculated to obtain the projection of each X-ray through accumulation of tri-linear interpolation. Considering projection angles, a rotation matrix is proposed to the X-ray source and the detector plane so projections in arbitrary angles can be got. In this approach the algorithm is easy to be extended and irregular objects can also be processed. The algorithm is implemented in Visual C++ and experiments are done using different models. Satisfactory results are obtained. It makes good preparation for the proceeding reconstruction

  17. Long-term stability of beam quality and output of conventional X-ray units.

    Science.gov (United States)

    Fukuda, Atsushi; Matsubara, Kosuke; Miyati, Tosiaki

    2015-01-01

    Conventional diagnostic X-ray units are used for radiographic imaging in many countries. For obtaining entrance surface doses, a numerical dose determination method has been applied in Japan. Although this technique is effective, it has to account for errors, particularly fluctuations, due to the beam quality and output of X-ray tubes. As a part of our quality control procedures, we recorded the entrance surface air kerma, tube voltage, and half-value layer measurements made for four diagnostic X-ray tubes over a 103-week period. The entrance surface air kerma for one of the four X-ray tubes had increased significantly by 11.4 % over 1 year from its initial setting, whereas the tube voltages and half-value layers did not deviate significantly from their initial values. Medical physicists and radiological technologists should be aware of this fluctuation for diagnostic X-ray tubes and take it into consideration when calculating the entrance surface air kerma.

  18. Spectrometry of X-ray beams using Cadmium and Zinc Teluride detector

    International Nuclear Information System (INIS)

    Becker, Paulo Henriques Bastos

    1997-06-01

    Determination of X-ray spectra to be utilized for medical diagnostics is a complementary process to the development of procedures to be applied to the quality control of radiodiagnostics X-ray equipment. Until some years ago, that was only possible using Germanium or Silicon detectors. Both have an excellent resolution in this energy range, but present also some restrictions as there are high costs and the necessity of operating them at temperature of liquid Nitrogen, which is not always available at the measurement's place. Room temperature detectors like Cadmium Telluride and Mercury Iodine don't have these restrictions. They, however, have a lower resolution and incomplete collection of the charges produced by their interaction with radiation. With technological advance of crystal growth in general and new techniques like cooling the crystal with a Peltier cell and rise time discrimination circuits, today Cadmium Telluride detectors show a resolution very close to that from Germanium detectors. This work relates to the routine use of Cadmium and Zinc Telluride detectors for measuring X-ray spectra in loco of diagnostic X-ray units. It characterizes the properties of a commercially available detector and offers a model for stripping the measured pulse height distribution. It was also developed a collimator to allow the direct measurement of the beam. The model developed and the constructed set-up were applied to two X-ray tubes and the achieved spectra compared with some spectra available from the literature. (author)

  19. Focusing of hard x-rays to 16 nanometers with a multilayer Laue lens

    International Nuclear Information System (INIS)

    Kang, Hyon Chol; Yan Hanfei; Winarski, Robert P.; Holt, Martin V.; Maser, Joerg; Liu Chian; Conley, Ray; Vogt, Stefan; Macrander, Albert T.; Stephenson, G. Brian

    2008-01-01

    We report improved results for hard x-ray focusing using a multilayer Laue lens (MLL). We have measured a line focus of 16 nm width with an efficiency of 31% at a wavelength λ=0.064 nm (19.5 keV) using a partial MLL structure with an outermost zone width of 5 nm. The results are in good agreement with the theoretically predicted performance

  20. Scanning-beam digital x-ray (SBDX) technology for interventional and diagnostic cardiac angiography

    International Nuclear Information System (INIS)

    Speidel, Michael A.; Wilfley, Brian P.; Star-Lack, Josh M.; Heanue, Joseph A.; Van Lysel, Michael S.

    2006-01-01

    The scanning-beam digital x-ray (SBDX) system is designed for x-ray dose reduction in cardiac angiographic applications. Scatter reduction, efficient detection of primary x-rays, and an inverse beam geometry are the main components of the entrance dose reduction strategy. This paper reports the construction of an SBDX prototype, image reconstruction techniques, and measurements of spatial resolution and x-ray output. The x-ray source has a focal spot that is electronically scanned across a large-area transmission target. A multihole collimator beyond the target defines a series of x-ray beams directed at a distant small-area detector array. The prototype has a 23 cmx23 cm target, 100x100 focal spot positions, and a 5 cmx5 cm CdTe detector positioned 150 cm from the target. With this nonmechanical method of beam scanning, patient images with low detected scatter are generated at up to 30 frame/s. SBDX data acquisition is tomosynthetic. The prototype simultaneously reconstructs 16 planes spaced throughout the cardiac volume using shift-and-add backprojection. Image frames analogous to conventional projection images are generated with a multiplane compositing algorithm. Single-plane versus multiplane reconstruction of contrast-filled coronary arteries is demonstrated with images of the porcine heart. Phantom and porcine imaging studies show multiplane reconstruction is practicable under clinically realistic levels of patient attenuation and cardiac motion. The modulation transfer function for an in-plane slit at mechanical isocenter measured 0.41-0.56 at 1 cycle/mm, depending on the detector element to image pixel interpolation technique. Modeling indicates that desired gains in spatial resolution are achievable by halving the detector element width. The x-ray exposure rate 15 cm below isocenter, without table or patient in the beam, measured 11.5 R/min at 120 kVp, 24.3 kWp and 3.42 R/min at 70 kVp, 14.2 kWp

  1. Exploring vacuum birefringence based on a 100 PW laser and an x-ray free electron laser beam

    Science.gov (United States)

    Shen, Baifei; Bu, Zhigang; Xu, Jiancai; Xu, Tongjun; Ji, Liangliang; Li, Ruxin; Xu, Zhizhan

    2018-04-01

    Exploring vacuum birefringence with the station of extreme light at Shanghai Coherent Light Facility is considered. Laser pulses of intensity beyond 1023 W cm-2 are capable of polarizing the vacuum due to the ultra-strong electro-magnetic fields. The subtle difference of the vacuum refractive indexes along electric and magnetic fields leads to a birefringence effect for lights propagating through. The vacuum birefringence effect can now be captured by colliding a hard x-ray free electron laser (XFEL) beam with a high-power laser. The initial XFEL beam of pure linear polarization is predicated to gain a very small ellipticity after passing through the laser stimulated vacuum. Various interaction geometries are considered, showing that the estimated ellipticity lies between 1.8 × 10-10 and 10-9 for a 100 PW laser interacting with a 12.9 keV XFEL beam, approaching the threshold for todays’ polarity detection technique. The detailed experimental set-up is designed, including the polarimeter, the focusing compound refractive lens and the optical path. When taking into account the efficiencies of the x-ray instruments, it is found that about 10 polarization-flipped x-ray photons can be detected for a single shot for our design. Considering the background noise level, accumulating runs are necessary to obtain high confident measurement.

  2. Device for the collimation of a high-energy beam, in particular a X-ray beam

    International Nuclear Information System (INIS)

    Peyser, L.F.

    1976-01-01

    The design of apertures made of radiation-absorbing material intended for limiting an aperture for a radiation beam of high energy, in particular an X-ray beam is claimed. The apertures are shaped as trapezoids, are held movably, and are adjustable by means of a control device. (UWI) [de

  3. Plasma focus as an x-ray source for tailoring of radiation in different energy windows

    International Nuclear Information System (INIS)

    Zakaullah, M.; Alamgir, K.; Shafiq, M.; Sharif, M.

    2001-01-01

    A low energy (2.3 kj) plasma focus energized by a single 32 micro f capacitor charged at 12 kv with filling gases hydrogen, neon and argon is investigated as an X-ray source. Experiments are conducted with a copper and an aluminum anode. Specifically, attention in given to tailoring the radiation in different windows, e. g. 1.2-1.3 keV, 1.3-1.5 keV, 2.5-5 keV and Cu-Ka line radiation. The highest X-ray emission is observed with neon filling and the copper anode in the 1.2-1.3 keV window, which speculated to be generated due to recombination of hydrogen like neon ions with a few eV to a few 10s of eV electrons. The wall-plug efficiency of the device is found to be 4%. The other significant emission occurs with Hydrogen filling, which exhibits wall plug efficiency of 1.7% for over all x-ray emission and 0.35% for Cu- Ka line radiation. The emission is dominated by the interaction of electrons in the current sheath with the anode tip. The emission with the aluminum anode and hydrogen filling is up to 10 j, which corresponds to wall-plug efficiency of 0.4%. The X-ray emission with argon filling is less significant. (author)

  4. Performance and beam characteristics of the PANTAK THERAPAX HF225 X-ray therapy machine

    Energy Technology Data Exchange (ETDEWEB)

    Yiannakkaras, C; Papadopoulos, N; Christodoulides, G [Department of Medical Physics, Nicosia General Hospital, 1450 Nicosia (Cyprus)

    1999-12-31

    The performance and beam characteristics of the new PANTAK THERAPAX HF225 X-ray therapy machine have been measured, evaluated and discussed. Eight beam qualities within the working range of generating potentials between 50 and 225 kVp are used in our department. These beam qualities have been investigated in order to provide a data base specific to our machine. Beam Quality, Central Axis Depth Dose, Output, Relative Field Uniformity and Timer Error were investigated. (authors) 11 refs., 4 figs., 9 tabs.

  5. Polychromatic X-ray Micro- and Nano-Beam Science and Instrumentation

    Science.gov (United States)

    Ice, G. E.; Larson, B. C.; Liu, W.; Barabash, R. I.; Specht, E. D.; Pang, J. W. L.; Budai, J. D.; Tischler, J. Z.; Khounsary, A.; Liu, C.; Macrander, A. T.; Assoufid, L.

    2007-01-01

    Polychromatic x-ray micro- and nano-beam diffraction is an emerging nondestructive tool for the study of local crystalline structure and defect distributions. Both long-standing fundamental materials science issues, and technologically important questions about specific materials systems can be uniquely addressed. Spatial resolution is determined by the beam size at the sample and by a knife-edge technique called differential aperture microscopy that decodes the origin of scattering from along the penetrating x-ray beam. First-generation instrumentation on station 34-ID-E at the Advanced Photon Source (APS) allows for nondestructive automated recovery of the three-dimensional (3D) local crystal phase and orientation. Also recovered are the local elastic-strain and the dislocation tensor distributions. New instrumentation now under development will further extend the applications of polychromatic microdiffraction and will revolutionize materials characterization.

  6. Polychromatic X-ray Micro- and Nano-Beam Science and Instrumentation

    International Nuclear Information System (INIS)

    Ice, G.E.; Larson, Ben C.; Liu, Wenjun; Barabash, Rozaliya; Specht, Eliot D; Pang, Judy; Budai, John D.; Tischler, Jonathan Zachary; Khounsary, Ali; Liu, Chian; Macrander, Albert T.; Assoufid, Lahsen

    2007-01-01

    Polychromatic x-ray micro- and nano-beam diffraction is an emerging nondestructive tool for the study of local crystalline structure and defect distributions. Both long-standing fundamental materials science issues, and technologically important questions about specific materials systems can be uniquely addressed. Spatial resolution is determined by the beam size at the sample and by a knife-edge technique called differential aperture microscopy that decodes the origin of scattering from along the penetrating x-ray beam. First-generation instrumentation on station 34-ID-E at the Advanced Photon Source (APS) allows for nondestructive automated recovery of the three-dimensional (3D) local crystal phase and orientation. Also recovered are the local elastic-strain and the dislocation tensor distributions. New instrumentation now under development will further extend the applications of polychromatic microdiffraction and will revolutionize materials characterization

  7. BEAM OPTIMIZATION STUDY FOR AN X-RAY FEL OSCILLATOR AT THE LCLS-II

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Weilun; Huang, S.; Liu, K.X.; Huang, Z; Ding, Y.; Maxwell, T.J.; Kim, K.-J.

    2016-06-01

    The 4 GeV LCLS-II superconducting linac with high repetition beam rate enables the possibility to drive an X-Ray FEL oscillator at harmonic frequencies *. Compared to the regular LCLS-II machine setup, the oscillator mode requires a much longer bunch length with a relatively lower current. Also a flat longitudinal phase space distribution is critical to maintain the FEL gain since the X-ray cavity has extremely narrow bandwidth. In this paper, we study the longitudinal phase space optimization including shaping the initial beam from the injector and optimizing the bunch compressor and dechirper parameters. We obtain a bunch with a flat energy chirp over 400 fs in the core part with current above 100 A. The optimization was based on LiTrack and Elegant simulations using LCLS-II beam parameters.

  8. Generation of low KV x-ray portal images with mega-voltage electron beams

    International Nuclear Information System (INIS)

    Kenny, J.; Ebert, M.

    2004-01-01

    Full text: The increasing complexity of radiation therapy plans and reduced target margins, have made accurate localization of patients at treatment a crucial quality assurance issue. Mega-voltage portal images, the standard for treatment localization, are inherently low in contrast because x-ray attenuation at these energies is similar for most body tissues. Thus anatomical features are difficult to distinguish and match to features on a reference diagnostic image. This project investigates the possibly of using x-rays created by an external target placed in the path of a clinical mega-voltage electron beam. This target is optimised to produce a higher proportion of useful imaging x-rays in the range of 50-200kV. It is thought that a high efficiency Varian aSi500 amorphous silicon EPID will be sufficient to compensate for the very low efficiency of x-ray production. The project was undertaken with concurrent theoretical and experimental components. The former involved Monte Carlo models of low Z target design while in the later, experimental data was gathered to validate the model and explore the practical issues associated with electron mode image acquisition. A 6 MeV electron beam model for a Varian Clinac 21EX was developed with EGS4/BEAMnrc User Code and compared to measured beam data. Phase space data scored at the secondary collimator then became the input for simulations of a target placed in the accessory tray. Target materials were predominately low atomic number (Z) because a) production of high energy x-rays is minimized and, b) fewer low energy x-rays produced will be absorbed within the target. Photon and electron energy spectrums of the modified beam were evaluated for a range of target geometries. Ultimately, several materials were used in combination to optimise an x-ray yield for energies <200kV while removing electrons and very low energy x-rays, that contribute to patient dose but not to image formation. Low energy images of a PIPs EPID QA

  9. Hard X-ray bremsstrahlung production in solar flares by high-energy proton beams

    Science.gov (United States)

    Emslie, A. G.; Brown, J. C.

    1985-01-01

    The possibility that solar hard X-ray bremsstrahlung is produced by acceleration of stationary electrons by fast-moving protons, rather than vice versa, as commonly assumed, was investigated. It was found that a beam of protons which involves 1836 times fewer particles, each having an energy 1836 times greater than that of the electrons in the equivalent electron beam model, has exactly the same bremsstrahlung yield for a given target, i.e., the mechanism has an energetic efficiency equal to that of conventional bremsstrahlung models. Allowance for the different degrees of target ionization appropriate to the two models (for conventional flare geometries) makes the proton beam model more efficient than the electron beam model, by a factor of order three. The model places less stringent constraints than a conventional electron beam model on the flare energy release mechanism. It is also consistent with observed X-ray burst spectra, intensities, and directivities. The altitude distribution of hard X-rays predicted by the model agrees with observations only if nonvertical injection of the protons is assumed. The model is inconsistent with gamma-ray data in terms of conventional modeling.

  10. Thermoluminescence of zirconium oxide nanostructured to mammography X-ray beams

    Energy Technology Data Exchange (ETDEWEB)

    Palacios, L.L. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada-Legaria, IPN. Av. Legaria 694, 11500 Mexico D.F. (Mexico); Rivera, T., E-mail: trivera@ipn.mx [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada-Legaria, IPN. Av. Legaria 694, 11500 Mexico D.F. (Mexico); Roman, J. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada-Legaria, IPN. Av. Legaria 694, 11500 Mexico D.F. (Mexico); Azorin, J. [Universidad Autonoma Metropolitana-Iztapalapa. Av. San Rafael Atlixco 187, 09340 Mexico D.F. (Mexico); Gaona, E. [Universidad Autonoma Metropolitana-Xochimilco. Calz. Del Hueso 1100, 04960 Mexico D.F. (Mexico)

    2012-07-15

    In the present work thermoluminescent (TL) response of zirconium oxide (ZrO{sub 2}) nanostructured induced by mammography X-ray radiation was investigated. Measurements were made of the response per unit air kerma of ZrO{sub 2} with mammography equipment parameters (semiautomatic exposure control, 24 kVp and 108 mAs). The calibration curves were obtained by simultaneously irradiating ZrO{sub 2} samples and ion chamber. Samples of ZrO{sub 2} showed a linear response as a function of entrance skin air kerma. The observed results in TL properties suggest that ZrO{sub 2} nanostructured could be considered as an effective material for X-ray beams dosimetry if appropriate calibration procedures are performed. - Highlights: Black-Right-Pointing-Pointer X-ray low energy thermoluminescent of ZrO{sub 2} dosimeter is developed. Black-Right-Pointing-Pointer Air kerma measurements were made by thermoluminescent dosimeter ZrO{sub 2} using mammography equipment parameters. Black-Right-Pointing-Pointer Entrance surface skin doses were made using thermoluminescent dosimeter of ZrO{sub 2} to X-ray beam quality control.

  11. In situ surface/interface x-ray diffractometer for oxide molecular beam epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J. H.; Freeland, J. W.; Hong, Hawoong, E-mail: hhong@aps.anl.gov [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Tung, I. C. [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208 (United States); Chang, S.-H.; Bhattacharya, A.; Fong, D. D. [Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

    2016-01-15

    In situ studies of oxide molecular beam epitaxy by synchrotron x-ray scattering has been made possible by upgrading an existing UHV/molecular beam epitaxy (MBE) six-circle diffractometer system. For oxide MBE growth, pure ozone delivery to the chamber has been made available, and several new deposition sources have been made available on a new 12 in. CF (ConFlat, a registered trademark of Varian, Inc.) flange. X-ray diffraction has been used as a major probe for film growth and structures for the system. In the original design, electron diffraction was intended for the secondary diagnostics available without the necessity of the x-ray and located at separate positions. Deposition of films was made possible at the two diagnostic positions. And, the aiming of the evaporation sources is fixed to the point between two locations. Ozone can be supplied through two separate nozzles for each location. Also two separate thickness monitors are installed. Additional features of the equipment are also presented together with the data taken during typical oxide film growth to illustrate the depth of information available via in situ x-ray techniques.

  12. LabVIEW control software for scanning micro-beam X-ray fluorescence spectrometer.

    Science.gov (United States)

    Wrobel, Pawel; Czyzycki, Mateusz; Furman, Leszek; Kolasinski, Krzysztof; Lankosz, Marek; Mrenca, Alina; Samek, Lucyna; Wegrzynek, Dariusz

    2012-05-15

    Confocal micro-beam X-ray fluorescence microscope was constructed. The system was assembled from commercially available components - a low power X-ray tube source, polycapillary X-ray optics and silicon drift detector - controlled by an in-house developed LabVIEW software. A video camera coupled to optical microscope was utilized to display the area excited by X-ray beam. The camera image calibration and scan area definition software were also based entirely on LabVIEW code. Presently, the main area of application of the newly constructed spectrometer is 2-dimensional mapping of element distribution in environmental, biological and geological samples with micrometer spatial resolution. The hardware and the developed software can already handle volumetric 3-D confocal scans. In this work, a front panel graphical user interface as well as communication protocols between hardware components were described. Two applications of the spectrometer, to homogeneity testing of titanium layers and to imaging of various types of grains in air particulate matter collected on membrane filters, were presented. Copyright © 2012 Elsevier B.V. All rights reserved.

  13. In situ surface/interface x-ray diffractometer for oxide molecular beam epitaxy

    International Nuclear Information System (INIS)

    Lee, J. H.; Freeland, J. W.; Hong, Hawoong; Tung, I. C.; Chang, S.-H.; Bhattacharya, A.; Fong, D. D.

    2016-01-01

    In situ studies of oxide molecular beam epitaxy by synchrotron x-ray scattering has been made possible by upgrading an existing UHV/molecular beam epitaxy (MBE) six-circle diffractometer system. For oxide MBE growth, pure ozone delivery to the chamber has been made available, and several new deposition sources have been made available on a new 12 in. CF (ConFlat, a registered trademark of Varian, Inc.) flange. X-ray diffraction has been used as a major probe for film growth and structures for the system. In the original design, electron diffraction was intended for the secondary diagnostics available without the necessity of the x-ray and located at separate positions. Deposition of films was made possible at the two diagnostic positions. And, the aiming of the evaporation sources is fixed to the point between two locations. Ozone can be supplied through two separate nozzles for each location. Also two separate thickness monitors are installed. Additional features of the equipment are also presented together with the data taken during typical oxide film growth to illustrate the depth of information available via in situ x-ray techniques

  14. Thermoluminescence of zirconium oxide nanostructured to mammography X-ray beams

    International Nuclear Information System (INIS)

    Palacios, L.L.; Rivera, T.; Roman, J.; Azorín, J.; Gaona, E.

    2012-01-01

    In the present work thermoluminescent (TL) response of zirconium oxide (ZrO 2 ) nanostructured induced by mammography X-ray radiation was investigated. Measurements were made of the response per unit air kerma of ZrO 2 with mammography equipment parameters (semiautomatic exposure control, 24 kVp and 108 mAs). The calibration curves were obtained by simultaneously irradiating ZrO 2 samples and ion chamber. Samples of ZrO 2 showed a linear response as a function of entrance skin air kerma. The observed results in TL properties suggest that ZrO 2 nanostructured could be considered as an effective material for X-ray beams dosimetry if appropriate calibration procedures are performed. - Highlights: ► X-ray low energy thermoluminescent of ZrO 2 dosimeter is developed. ► Air kerma measurements were made by thermoluminescent dosimeter ZrO 2 using mammography equipment parameters. ► Entrance surface skin doses were made using thermoluminescent dosimeter of ZrO 2 to X-ray beam quality control.

  15. First dedicated in-beam X-ray measurement in heavy-ion fusion reactions

    Energy Technology Data Exchange (ETDEWEB)

    Berner, C. [Technische Universitaet Muenchen, Lehrstuhl E12 (Germany); RIKEN, Research Group for Superheavy Elements (Japan); Henning, W. [Argonne National Laboratory, Physics Division (United States); RIKEN, Research Group for Superheavy Elements (Japan); Muecher, D.; Gernhaeuser, R.; Hellgartner, S.; Maier, L. [Technische Universitaet Muenchen, Lehrstuhl E12 (Germany); Morita, K.; Morimoto, K.; Kaji, D.; Wakabayashi, Y.; Baba, H. [RIKEN, Research Group for Superheavy Elements (Japan); Lutter, R. [Ludwig-Maximilians-Universitaet, Muenchen (Germany)

    2016-07-01

    We report on an experiment aiming at in-beam X-ray spectroscopy of heavy and superheavy elements (SHE). The goal is to establish K-X-ray spectroscopy as a sensitive tool to identify SHE produced in fusion reactions. SHE, formed after cold or hot fusion, are usually identified via the alpha-decay products, which have to be connected to well-known elements. However, various theories predict spontaneous fission as the dominant decay mode for the daughter nuclides. Additionally, half-lives of these elements are expected to increase to values impeding the identification of SHE solely by their decay. The in-beam identification of the characteristic X-rays would precisely allow to identify the charge number of the produced SHE. Experiments were performed at the RIKEN Nishina Centre for Accelerator based Science by using the gas-filled magnet separator GARIS for superheavy element detection. A high-purity, low-energy planar germanium LEGe-detector was adapted to the GARIS system at the target place for the first time in order to measure the element-characteristic, prompt X-ray emission.

  16. Fluctuations on the X-ray intensity beam using a portable X-ray probe based on {sup 6}LiI(Eu) crystal

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Geraldo P.; Oliveira, Arno H. [Universidade Federal de Minas Gerais (PCTN/UFMG), Belo Horizonte, MG (Brazil). Programa de Pos-Graduacao em Ciencias e Tecnicas Nucleares; Carneiro, Andre C.; Carneiro, Clemente J.G.; Milian, Felix M.; Velasco, Fermin G., E-mail: fermin@uesc.b [Universidade Estadual de Santa Cruz (CPqCTR/UESC), Ilheus, BA (Brazil). Centro de Pesquisa em Ciencias e Tecnologias das Radiacoes

    2011-07-01

    X-rays are produced by accelerating electrons with a high voltage and allowing them to collide with a metal target. This high voltage presents fluctuations that define peak, minimum, and average voltages. Different voltages are applied to the X-ray tube depending on the radiographic applications. A rectifier circuit converts the alternating high voltage to unidirectional high voltage to accelerate electrons in this tube. The fluctuations on the energy in the electron beam depend on the mode of rectification. Both energy of the electrons and X rays intensity fluctuates. A portable probe built with a {sup 6}LiI(Eu) detector coupled to a 10 m light guide and a Hamamatsu photon counting head H9319 was used to measuring X ray intensities. This system is designed to collect up to 10000 counts in intervals of 10 ms to 1 s. Counts were accumulated in time intervals of 10 ms during 10 s. The system starts the count before activating the X-ray apparatus, which is on during a time interval of 100ms. During this period, counts may overflow in consequence high voltage was adjusted to be 40kV, in order to avoid such a problem. For each of these points dose was measured using an ionization chamber. The objectives of this work are to study fluctuations on the X-ray beam and to calibrate the portable probe for measuring radiation doses. Counting rates measured for each 10 ms presented strong variations due to high voltages fluctuations. Both dose and counting rate when correlated with distances between source and detector followed the inverse square law and presented values of R2 near of unit. A calibration curve of the portable system for dose measurements showed also R2 value near of unity. (author)

  17. Multilayer Laue Lens: A Path Toward One Nanometer X-Ray Focusing

    International Nuclear Information System (INIS)

    Yan, H.; Stephenson, G.B.; Maser, J.; Yan, H.; Conley, R.; Kang, H.C.; Stephenson, G.B.; Kang, H.C.; Maser, J.; Conley, R.; Liu, Ch.; Macrander, A.T.

    2010-01-01

    The multilayer Laue lens (MLL) is a novel diffractive optic for hard X-ray nano focusing, which is fabricated by thin film deposition techniques and takes advantage of the dynamical diffraction effect to achieve a high numerical aperture and efficiency. It overcomes two difficulties encountered in diffractive optics fabrication for focusing hard X-rays: (1) small outmost zone width and (2) high aspect ratio. Here, we will give a review on types, modeling approaches, properties, fabrication, and characterization methods of MLL optics. We show that a full-wave dynamical diffraction theory has been developed to describe the dynamical diffraction property of the MLL and has been employed to design the optimal shapes for nano focusing. We also show a 16 nm line focus obtained by a partial MLL and several characterization methods. Experimental results show a good agreement with the theoretical calculations. With the continuing development of MLL optics, we believe that an MLL-based hard x-ray microscope with true nanometer resolution is on the horizon

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

    International Nuclear Information System (INIS)

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

    1993-06-01

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

  19. Self-standing quasi-mosaic crystals for focusing hard X-rays

    International Nuclear Information System (INIS)

    Camattari, Riccardo; Guidi, Vincenzo; Bellucci, Valerio; Neri, Ilaria; Frontera, Filippo; Jentschel, Michael

    2013-01-01

    A quasi mosaic bent crystal for high-resolution diffraction of X and γ rays has been realized. A net curvature was imprinted to the crystal thanks to a series of superficial grooves to keep the curvature without external devices. The crystal highlights very high diffraction efficiency due to quasi mosaic curvature. Quasi mosaic crystals of this kind are proposed for the realization of a high-resolution focusing Laue lens for hard X-rays.

  20. Cone Beam X-Ray Luminescence Tomography Imaging Based on KA-FEM Method for Small Animals.

    Science.gov (United States)

    Chen, Dongmei; Meng, Fanzhen; Zhao, Fengjun; Xu, Cao

    2016-01-01

    Cone beam X-ray luminescence tomography can realize fast X-ray luminescence tomography imaging with relatively low scanning time compared with narrow beam X-ray luminescence tomography. However, cone beam X-ray luminescence tomography suffers from an ill-posed reconstruction problem. First, the feasibility of experiments with different penetration and multispectra in small animal has been tested using nanophosphor material. Then, the hybrid reconstruction algorithm with KA-FEM method has been applied in cone beam X-ray luminescence tomography for small animals to overcome the ill-posed reconstruction problem, whose advantage and property have been demonstrated in fluorescence tomography imaging. The in vivo mouse experiment proved the feasibility of the proposed method.

  1. Characterization of continuous and pulsed emission modes of a hybrid micro focus x-ray source for medical imaging applications

    Energy Technology Data Exchange (ETDEWEB)

    Ghani, Muhammad U.; Wong, Molly D.; Ren, Liqiang; Wu, Di; Zheng, Bin [Center for Biomedical Engineering and School of Electrical and Computer Engineering, University of Oklahoma, Norman, OK 73019 (United States); Rong, John X. [Department of Imaging Physics, University of Texas MD Anderson Cancer Center, Houston, TX 77030 (United States); Wu, Xizeng [Department of Radiology, University of Alabama at Birmingham, Birmingham, AL 35249 (United States); Liu, Hong, E-mail: liu@ou.edu [Center for Biomedical Engineering and School of Electrical and Computer Engineering, University of Oklahoma, Norman, OK 73019 (United States)

    2017-05-01

    The aim of this study was to quantitatively characterize a micro focus x-ray tube that can operate in both continuous and pulsed emission modes. The micro focus x-ray source (Model L9181-06, Hamamatsu Photonics, Japan) has a varying focal spot size ranging from 16 µm to 50 µm as the source output power changes from 10 to 39 W. We measured the source output, beam quality, focal spot sizes, kV accuracy, spectra shapes and spatial resolution. Source output was measured using an ionization chamber for various tube voltages (kVs) with varying current (µA) and distances. The beam quality was measured in terms of half value layer (HVL), kV accuracy was measured with a non-invasive kV meter, and the spectra was measured using a compact integrated spectrometer system. The focal spot sizes were measured using a slit method with a CCD detector with a pixel pitch of 22 µm. The spatial resolution was quantitatively measured using the slit method with a CMOS flat panel detector with a 50 µm pixel pitch, and compared to the qualitative results obtained by imaging a contrast bar pattern. The focal spot sizes in the vertical direction were smaller than that of the horizontal direction, the impact of which was visible when comparing the spatial resolution values. Our analyses revealed that both emission modes yield comparable imaging performances in terms of beam quality, spectra shape and spatial resolution effects. There were no significantly large differences, thus providing the motivation for future studies to design and develop stable and robust cone beam imaging systems for various diagnostic applications. - Highlights: • A micro focus x-ray source that operates in both continuous and pulse emission modes was quantitatively characterized. • The source output, beam quality, focal spot measurements, kV accuracy, spectra analyses and spatial resolution were measured. • Our analyses revealed that both emission modes yield comparable imaging performances in terms of beam

  2. Characterization of continuous and pulsed emission modes of a hybrid micro focus x-ray source for medical imaging applications

    International Nuclear Information System (INIS)

    Ghani, Muhammad U.; Wong, Molly D.; Ren, Liqiang; Wu, Di; Zheng, Bin; Rong, John X.; Wu, Xizeng; Liu, Hong

    2017-01-01

    The aim of this study was to quantitatively characterize a micro focus x-ray tube that can operate in both continuous and pulsed emission modes. The micro focus x-ray source (Model L9181-06, Hamamatsu Photonics, Japan) has a varying focal spot size ranging from 16 µm to 50 µm as the source output power changes from 10 to 39 W. We measured the source output, beam quality, focal spot sizes, kV accuracy, spectra shapes and spatial resolution. Source output was measured using an ionization chamber for various tube voltages (kVs) with varying current (µA) and distances. The beam quality was measured in terms of half value layer (HVL), kV accuracy was measured with a non-invasive kV meter, and the spectra was measured using a compact integrated spectrometer system. The focal spot sizes were measured using a slit method with a CCD detector with a pixel pitch of 22 µm. The spatial resolution was quantitatively measured using the slit method with a CMOS flat panel detector with a 50 µm pixel pitch, and compared to the qualitative results obtained by imaging a contrast bar pattern. The focal spot sizes in the vertical direction were smaller than that of the horizontal direction, the impact of which was visible when comparing the spatial resolution values. Our analyses revealed that both emission modes yield comparable imaging performances in terms of beam quality, spectra shape and spatial resolution effects. There were no significantly large differences, thus providing the motivation for future studies to design and develop stable and robust cone beam imaging systems for various diagnostic applications. - Highlights: • A micro focus x-ray source that operates in both continuous and pulse emission modes was quantitatively characterized. • The source output, beam quality, focal spot measurements, kV accuracy, spectra analyses and spatial resolution were measured. • Our analyses revealed that both emission modes yield comparable imaging performances in terms of beam

  3. Application of the entropy concept to describe the quality of a X-ray beam

    International Nuclear Information System (INIS)

    Oliveira, A.D.

    2002-01-01

    In a previous work (Oliveira and Pedroso de Lima, 2000), we introduced the concept of entropy to describe the degradation of the energy of a photon beam incident in a material. We pointed out the relation between both, the entropy of the distribution of the energy deposited in matter and the traditional quality factor of the radiation protection. From the point of view of the entropy, we showed that, in what concerns to the monoenergetic approximation to a polyenergetic beam, we can hardly speak in an approximation (Oliveira 2001). In fact, the behaviour of the entropy is very different for both, an X-ray and a monoenergetic beam. In this work we developed further the study of the degradation of the energy of X-ray photons, from the point of view of the entropy, introducing the concepts of surface entropy, S surf , equilibrium entropy, S eq , and concepts of entropy variation, namely, primary to surface variation, S ps , and total entropy variation, S T . These are characteristic parameters of the X-ray beams describing the degradation of the primary photons while they interact with matter

  4. Modeling the focusing efficiency of lobster-eye optics for image shifting depending on the soft x-ray wavelength.

    Science.gov (United States)

    Su, Luning; Li, Wei; Wu, Mingxuan; Su, Yun; Guo, Chongling; Ruan, Ningjuan; Yang, Bingxin; Yan, Feng

    2017-08-01

    Lobster-eye optics is widely applied to space x-ray detection missions and x-ray security checks for its wide field of view and low weight. This paper presents a theoretical model to obtain spatial distribution of focusing efficiency based on lobster-eye optics in a soft x-ray wavelength. The calculations reveal the competition mechanism of contributions to the focusing efficiency between the geometrical parameters of lobster-eye optics and the reflectivity of the iridium film. In addition, the focusing efficiency image depending on x-ray wavelengths further explains the influence of different geometrical parameters of lobster-eye optics and different soft x-ray wavelengths on focusing efficiency. These results could be beneficial to optimize parameters of lobster-eye optics in order to realize maximum focusing efficiency.

  5. Influence of beam divergence on form-factor in X-ray diffraction radiation

    International Nuclear Information System (INIS)

    Sergeeva, D.Yu.; Tishchenko, A.A.; Strikhanov, M.N.

    2015-01-01

    Diffraction radiation from divergent beam is considered in terms of radiation in UV and X-ray range. Scedastic form of Gaussian distribution of the particle in the bunch, i.e. Gaussian distribution with changing dispersion has been used, which is more adequate for description of divergent beams than often used Gaussian distribution with constant dispersion. Both coherent and incoherent form-factors are taken into account. The conical diffraction effect in diffraction radiation is proved to make essential contribution in spectral-angular characteristics of radiation from a divergent beam

  6. Comparison of neutron and high-energy X-ray dual-beam radiography for air cargo inspection

    International Nuclear Information System (INIS)

    Liu, Y.; Sowerby, B.D.; Tickner, J.R.

    2008-01-01

    Dual-beam radiography techniques utilising various combinations of high-energy X-rays and neutrons are attractive for screening bulk cargo for contraband such as narcotics and explosives. Dual-beam radiography is an important enhancement to conventional single-beam X-ray radiography systems in that it provides additional information on the composition of the object being imaged. By comparing the attenuations of transmitted dual high-energy beams, it is possible to build a 2D image, colour coded to indicate material. Only high-energy X-rays, gamma-rays and neutrons have the required penetration to screen cargo containers. This paper reviews recent developments and applications of dual-beam radiography for air cargo inspection. These developments include dual high-energy X-ray techniques as well as fast neutron and gamma-ray (or X-ray) radiography systems. High-energy X-ray systems have the advantage of generally better penetration than neutron systems, depending on the material being interrogated. However, neutron systems have the advantage of much better sensitivity to material composition compared to dual high-energy X-ray techniques. In particular, fast neutron radiography offers the potential to discriminate between various classes of organic material, unlike dual energy X-ray techniques that realistically only offer the ability to discriminate between organic and metal objects

  7. National Synchrotron Light Source users manual: Guide to the VUV and x-ray beam lines

    International Nuclear Information System (INIS)

    Gmuer, N.F.; White-DePace, S.M.

    1987-08-01

    The success of the National Synchrotron Light Source in the years to come will be based, in large part, on the size of the users community and the diversity of the scientific disciplines represented by these users. In order to promote this philosophy, this National Synchrotron Light Source (NSLS) Users Manual: Guide to the VUV and X-Ray Beam Lines, has been published. This manual serves a number of purposes. In an effort to attract new research, it will present to the scientific community-at-large the current and projected architecture and capabilities of the various VUV and x-ray beam lines and storage rings. We anticipate that this publication will be updated periodically in order to keep pace with the constant changes at the NSLS

  8. Soft X-ray spectroscopic investigation of a plasma focus operated in pure neon

    International Nuclear Information System (INIS)

    Presura, R.; Zoita, V.; Paraschiv, I.

    1996-01-01

    The soft X-ray emission of the medium-energy plasma focus device IPF-2/20 operated in pure neon was studied with spectral resolution. The spectra of H- and He-like Ne ions were recorded by means of a de Broglie spectrograph for initial filling pressures in the range 1.3 to 7 torr. Both the soft X-ray emission characteristics and the plasma parameters are strongly dependent on the working gas pressure. The intensity of the He-like neon ions lines increases when the working gas pressure is raised, while for the H-like ions it has a maximum for about 5 torr filling. The electron density has values of the order of 10 20 cm -3 . The electron temperature ranges between 300 and 350 eV. Both the plasma density and the plasma temperature decrease when the initial gas pressure is increased. (author). 2 figs., 9 refs

  9. Soft X-ray spectroscopic investigation of a plasma focus operated in pure neon

    Energy Technology Data Exchange (ETDEWEB)

    Presura, R; Zoita, V; Paraschiv, I [Inst. of Physics and Technology of Radiation Devices, Bucharest (Romania)

    1997-12-31

    The soft X-ray emission of the medium-energy plasma focus device IPF-2/20 operated in pure neon was studied with spectral resolution. The spectra of H- and He-like Ne ions were recorded by means of a de Broglie spectrograph for initial filling pressures in the range 1.3 to 7 torr. Both the soft X-ray emission characteristics and the plasma parameters are strongly dependent on the working gas pressure. The intensity of the He-like neon ions lines increases when the working gas pressure is raised, while for the H-like ions it has a maximum for about 5 torr filling. The electron density has values of the order of 10{sup 20} cm{sup -3}. The electron temperature ranges between 300 and 350 eV. Both the plasma density and the plasma temperature decrease when the initial gas pressure is increased. (author). 2 figs., 9 refs.

  10. Highly ionized copper contribution to the soft X-ray emission in a plasma focus device

    Energy Technology Data Exchange (ETDEWEB)

    Zoita, V; Patran, A [Inst. of Physics and Technology of Radiation Devices, Bucharest (Romania); Larour, J [Ecole Polytechnique, Palaiseau (France). Lab. de Physique des Milieux Ionises

    1997-12-31

    In order to discriminate between the contributions of the gas plasma and of the anode (solid or plasma) to the soft X-ray emission in a plasma focus device, a series of experiments was carried out using the following combinations of experimental conditions: various gases, different absorption filters and viewing different regions in front of the centre electrode. The experiments were performed on the IPF-2/20 plasma focus device using the following working gases: helium, neon and helium-argon mixtures. The diagnostics used: magnetic probe for current derivative, PIN diode for the minimum pinch radius detection, PIN diodes for the soft X-ray emission, scintillator-photomultiplier detector for the hard X-ray emission. From the analysis of the various diagnostics data recorded with very good time correlation, it followed that the soft K-ray signals had a strong contribution from optical transitions of the highly ionised Cu (Cu XX to XXII) emitting in the range 0.8-1.3 nm. (author). 7 figs., 9 refs.

  11. Assessment of image quality in x-ray radiography imaging using a small plasma focus device

    Science.gov (United States)

    Kanani, A.; Shirani, B.; Jabbari, I.; Mokhtari, J.

    2014-08-01

    This paper offers a comprehensive investigation of image quality parameters for a small plasma focus as a pulsed hard x-ray source for radiography applications. A set of images were captured from some metal objects and electronic circuits using a low energy plasma focus at different voltages of capacitor bank and different pressures of argon gas. The x-ray source focal spot of this device was obtained to be about 0.6 mm using the penumbra imaging method. The image quality was studied by several parameters such as image contrast, line spread function (LSF) and modulation transfer function (MTF). Results showed that the contrast changes by variations in gas pressure. The best contrast was obtained at a pressure of 0.5 mbar and 3.75 kJ stored energy. The results of x-ray dose from the device showed that about 0.6 mGy is sufficient to obtain acceptable images on the film. The measurements of LSF and MTF parameters were carried out by means of a thin stainless steel wire 0.8 mm in diameter and the cut-off frequency was obtained to be about 1.5 cycles/mm.

  12. Time and space domain separation of pulsed X-ray beams diffracted from vibrating crystals

    Energy Technology Data Exchange (ETDEWEB)

    Nosik, V. L., E-mail: v-nosik@yandex.ru, E-mail: nosik@ns.crys.ras.ru [Russian Academy of Sciences, Shubnikov Institute of Crystallography, Federal Scientific Research Centre “Crystallography and Photonics,” (Russian Federation)

    2016-11-15

    It is known that a set of additional reflections (satellites) may arise on rocking curves in the case of X-ray diffraction in the Bragg geometry from crystals where high-frequency ultrasonic vibrations are excited. It is shown that, under certain conditions, the pulse wave fields of the satellites and main reflection may be intersected in space (playing the role of pump and probe beams) and in time (forming interference superlattices).

  13. Parallel beam microradiography of dental hard tissue using synchrotron radiation and X-ray image magnification

    International Nuclear Information System (INIS)

    Takagi, S.; Chow, L.C.; Brown, W.E.; Dobbyn, R.C.; Kuriyama, M.

    1984-01-01

    A novel technique utilizing a highly parallel beam of monochromatic synchrotron radiation combined with X-ray image magnification has been used to obtain microradiographs of caries lesions in relatively thick tooth sections. Preliminary results reveal structural features not previously reported. This technique holds the promise of allowing one to follow the structural changes accompanying the formation, destruction and chemical repair of mineralized tissue in real time. (orig.)

  14. Absorbed dose determination in water in medium energy x-ray beam

    International Nuclear Information System (INIS)

    Nisevic, G.; Spasic-Jokic, V.

    1998-01-01

    Absorbed dose determination in water phantom in medium energy X-ray beam, according to IAEA recommendations is given. This method is applied on Radiotherapy department of Military Academy Hospital in Belgrade. Reference points of measurements are on depth of 5 cm and 2 cm as it recommended in ref. Experimental results are shown in aim to introduce new dosimetric concept based on air kerma calibration factor recommended for application in our radiotherapy centers (author)

  15. Dose reduction by x-ray beam filtration in screen-film radiography

    International Nuclear Information System (INIS)

    Koedooder, C.

    1986-01-01

    This thesis describes experimental and theoretical aspects of dose reduction by x-ray beam filtration in screen-film radiography. The thesis deals mainly with dose reduction under the constraint of constant image quality; an analytical approach is chosen. Therefore, part of the thesis deals with the development of an algorithm to calculate patient dose and exposure for different filter materials and different tube load conditions, under the constraint of constant contrast and constant optical density. (Auth.)

  16. Impact of large x-ray beam collimation on image quality

    Science.gov (United States)

    Racine, Damien; Ba, Alexandre; Ott, Julien G.; Bochud, François O.; Verdun, Francis R.

    2016-03-01

    Large X-ray beam collimation in computed tomography (CT) opens the way to new image acquisition techniques and improves patient management for several clinical indications. The systems that offer large X-ray beam collimation enable, in particular, a whole region of interest to be investigated with an excellent temporal resolution. However, one of the potential drawbacks of this option might be a noticeable difference in image quality along the z-axis when compared with the standard helical acquisition mode using more restricted X-ray beam collimations. The aim of this project is to investigate the impact of the use of large X-ray beam collimation and new iterative reconstruction on noise properties, spatial resolution and low contrast detectability (LCD). An anthropomorphic phantom and a custom made phantom were scanned on a GE Revolution CT. The images were reconstructed respectively with ASIR-V at 0% and 50%. Noise power spectra, to evaluate the noise properties, and Target Transfer Functions, to evaluate the spatial resolution, were computed. Then, a Channelized Hotelling Observer with Gabor and Dense Difference of Gaussian channels was used to evaluate the LCD using the Percentage correct as a figure of merit. Noticeable differences of 3D noise power spectra and MTF have been recorded; however no significant difference appeared when dealing with the LCD criteria. As expected the use of iterative reconstruction, for a given CTDIvol level, allowed a significant gain in LCD in comparison to ASIR-V 0%. In addition, the outcomes of the NPS and TTF metrics led to results that would contradict the outcomes of CHO model observers if used for a NPWE model observer (Non- Prewhitening With Eye filter). The unit investigated provides major advantages for cardiac diagnosis without impairing the image quality level of standard chest or abdominal acquisitions.

  17. New x-ray parallel beam facility XPBF 2.0 for the characterization of silicon pore optics

    Science.gov (United States)

    Krumrey, Michael; Müller, Peter; Cibik, Levent; Collon, Max; Barrière, Nicolas; Vacanti, Giuseppe; Bavdaz, Marcos; Wille, Eric

    2016-07-01

    A new X-ray parallel beam facility (XPBF 2.0) has been installed in the laboratory of the Physikalisch-Technische Bundesanstalt at the synchrotron radiation facility BESSY II in Berlin to characterize silicon pore optics (SPOs) for the future X-ray observatory ATHENA. As the existing XPBF which is operated since 2005, the new beamline provides a pencil beam of very low divergence, a vacuum chamber with a hexapod system for accurate positioning of the SPO to be investigated, and a vertically movable CCD-based camera system to register the direct and the reflected beam. In contrast to the existing beamline, a multilayer-coated toroidal mirror is used for beam monochromatization at 1.6 keV and collimation, enabling the use of beam sizes between about 100 μm and at least 5 mm. Thus the quality of individual pores as well as the focusing properties of large groups of pores can be investigated. The new beamline also features increased travel ranges for the hexapod to cope with larger SPOs and a sample to detector distance of 12 m corresponding to the envisaged focal length of ATHENA.

  18. Dental X-ray apparatus

    International Nuclear Information System (INIS)

    Weiss, M.E.

    1980-01-01

    Intra-oral dental X-ray apparatus for panoramic dental radiography is described in detail. It comprises an electron gun having an elongated tubular target carrier extending into the patient's mouth. The carrier supports an inclined target for direction of an X-ray pattern towards a film positioned externally of the patient's mouth. Image definition is improved by a focusing anode which focuses the electron beam into a sharp spot (0.05 to 0.10 mm diameter) on the target. The potential on the focusing anode is adjustable to vary the size of the spot. An X-ray transmitting ceramic (oxides of Be, Al and Si) window is positioned adjacent to the front face of the target. The electron beam can be magnetically deflected to change the X-ray beam direction. (author)

  19. Optical and x-ray imaging of electron beams using synchrotron emission

    International Nuclear Information System (INIS)

    Wilke, M.

    1995-01-01

    In the case of very low emittance electron and positron storage ring beams, it is impossible to make intrusive measurements of beam properties without increasing the emittance and possibly disrupting the beam. In cases where electron or positron beams have high average power densities (such as free electron laser linacs), intrusive probes such as wires and optical transition radiation screens or Cherenkov emitting screens can be easily damaged or destroyed. The optical and x-ray emissions from the bends in the storage rings and often from linac bending magnets can be used to image the beam profile to obtain emittance information about the beam. The techniques, advantages and limitations of using both optical and x-ray synchrotron emission to measure beam properties are discussed and the possibility of single bunch imaging is considered. The properties of suitable imagers and converters such as phosphors are described. Examples of previous, existing and planned applications are given where available, including a pinhole imaging system currently being designed for the Advanced Photon Source at Argonne National Laboratory

  20. Optical and x-ray imaging of electron beams using synchrotron emission

    International Nuclear Information System (INIS)

    Wilke, M.D.

    1994-01-01

    In the case of very low eniittance electron and positron storage ring beams, it is impossible to make intrusive measurements of beam properties without increasing the emittance and possibly disrupting the beam. In cases where electron or positron beams have high average power densities (such as free electron laser linacs), intrusive probes such as wires and optical transition radiation screens or Cherenkov emitting screens can be easily damaged or destroyed. The optical and x-ray emissions from the bends in the storage rings and often from linac bending magnets can be used to image the beam profile to obtain emittance information about the beam. The techniques, advantages and limitations of using both optical and x-ray synchrotron emission to measure beam properties are discussed and the possibility of single bunch imaging is considered. The properties of suitable imagers and converters such as phosphors are described. Examples of previous, existing and planned applications are given where available, including a pinhole imaging system currently being designed for the Advanced Photon Source at Argonne National Laboratory

  1. Polarization of X-ray lines emitted from plasma-focus discharges; Problems of interpretation

    International Nuclear Information System (INIS)

    Jakubowski, L.

    2002-01-01

    In high current pulse discharges of the Plasma Focus (PF) type, inside the collapsing pinch column, there are formed local micro-regions of high-density and high-temperature plasma, so-called hot spots. Individual hot spots are separated in space and time. Each hot spot is characterized by its specific electron concentration and temperature, as well as by the emission of X-ray lines with different polarization. When numerous hot spots are produced it is impossible to determine local plasma parameters and to interpret the polarization effects. To eliminate this problem this study was devoted to the realization of PF-type discharges with single hot spot only. It has been achieved by a choice of the electrode configuration, which facilitated the formation of a single hot spot emitting intense X-ray lines. At the chosen experimental conditions it was possible to determine local plasma parameters and to demonstrate evident differences in the polarization of the observed X-ray lines. (author)

  2. X-ray polarization studies of plasma focus experiments with a single hot spots

    International Nuclear Information System (INIS)

    Jakubowski, L.; Sadowski, M.J.; Baronova, E.O.

    2004-01-01

    In high current pulse discharges of the plasma focus (PF) type, inside the collapsing pinch column, there are formed local micro-regions of high-density and high-temperature plasma, so-called hot spots. Individual hot spots are separated in space and time. Each hot spot is characterized by its specific electron concentration and temperature, as well as by the emission of x-ray lines with different polarization. When numerous hot spots are produced it is impossible to determine local plasma parameters and to interpret the polarization effects. To eliminate this problem this study was devoted to the realization of PF-type discharges with single hot spot only. It has been achieved by a choice of the electrode configuration, which facilitated the formation of a single hot spot emitting intense x-ray lines. At the chosen experimental conditions it was possible to determine local plasma parameters and to demonstrate evident differences in the polarization of the observed x-ray lines. (author)

  3. Polarization of x-ray lines emitted from plasma-focus discharges; Problems of interpretation

    International Nuclear Information System (INIS)

    Jakubowski, L.; Sadowski, M.J.; Baronova, E.O.

    2003-01-01

    In high current pulse discharges of the Plasma Focus (PF) type, inside the collapsing pinch column, there are formed local micro-regions of high-density and high-temperature plasma, so-called hot spots. Individual hot spots are separated in space and time. Each hot spot is characterized by its specific electron concentration and temperature, as well as by the emission of X-ray lines with different polarization. When numerous hot spots are produced it is impossible to determine local plasma parameters and to interpretate the polarization effects. To eliminate this problem this study was devoted to the realization of PF-type discharges with single hot spot only. It has been achieved by a choice of the electrode configuration, which facilitated the formation of a single hot spot emitting intense X-ray lines. At the chosen experimental conditions it was possible to determine local plasma parameters and to demonstrate evident differences in the polarization of the observed X-ray lines. (author)

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

    International Nuclear Information System (INIS)

    Hall, C

    2013-01-01

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

  5. X-ray study of a test quadrant of the SODART telescopes using the expanded beam x-ray optics facility at the Daresbury synchrotron

    DEFF Research Database (Denmark)

    Christensen, Finn Erland; Hornstrup, Allan; Frederiksen, P.

    1994-01-01

    The imaging properties of a test model of the SODART telescopes have been studied using an expanded beam X-ray facility at the Daresbury synchrotron. The encircled power and the point spread function at three energies 6.627 keV, 8.837 keV and 11.046 keV have been measured using 1D and 2D position...

  6. Characterization of ion-beam mixed multilayers via grazing x-ray reflectometry

    International Nuclear Information System (INIS)

    Le Boite, M.G.; Traverse, A.; Nevot, L.; Pardo, B.; Corno, J.

    1988-01-01

    The grazing x-ray reflectrometry technique was used as a way to study modifications in metallic multilayers induced by ion-beam irradiation. Due to the high sensitivity of the technique, short-range atomic displacements of an atom A in a layer B can be detected so that the first stages of ion-beam mixing can be investigated. The rate of mixing is measured and the compound A/sub 1-//sub x/B/sub x/ formed at the layers' interfaces is characterized

  7. X-ray spectroscopy of hydrogen-like ions in an electron beam ion trap

    Energy Technology Data Exchange (ETDEWEB)

    Tarbutt, M.R.; Crosby, D.; Silver, J.D. [Univ. of Oxford, Clarendon Lab. (United Kingdom); Myers, E.G. [Dept. of Physics, Florida State Univ., Tallahassee, FL (United States); Nakamura, N.; Ohtani, S. [ICORP, JST, Chofu, Tokyo (Japan)

    2001-07-01

    The X-ray emission from highly charged hydrogen-like ions in an electron beam ion trap is free from the problems of satellite contamination and Doppler shifts inherent in fast-beam sources. This is a favourable situation for the measurement of ground-state Lamb shifts in these ions. We present recent progress toward this goal, and discuss a method whereby wavelength comparison between transitions in hydrogenlike ions of different nuclear charge Z, enable the measurement of QED effects without requiring an absolute calibration.

  8. X-ray beam penetration in TXRF measurement of polycrystalline and amorphous surfaces

    International Nuclear Information System (INIS)

    Ghatak-Roy, A.R.; Hossain, T.Z.

    2000-01-01

    For TXRF measurement on single crystal silicon surface, it is generally agreed that the x-ray beam penetration is of the order of a few hundred Angstroms from the surface. However, for polycrystalline and amorphous surfaces - frequently used in semiconductor manufacturing there are evidences that x-rays penetrate much deeper revealing underlying layers. The evidences come from various measurements done with films such as silicon dioxide, silicon nitride and metal films such as aluminum, titanium and cobalt. A systematic study was carried out to help understand the issue further. Four sets of samples (on 8 inch wafers) were prepared to create layers buried under various deposited metal and non-metal layers. The metal layers created were aluminum, titanium and cobalt and the non-metal layers were silicon dioxide and silicon nitride. These samples were analyzed by TXRF under various angles and energies and the data were analyzed for signals from various buried layers along with their angular dependence. The results indicated deep penetration of x-ray beams. The samples were further analyzed by SIMS (Secondary Ion Mass Spectrometry) and some of them by ICP-MS (Inductively Coupled Plasma - Mass Spectrometry) to obtain information about their depth profiles. This was done in order to rule out the possibility of intermixing of layers during deposition. (author)

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

    International Nuclear Information System (INIS)

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

    1994-09-01

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

  10. Optimization of neon soft X-ray emission from 200 J plasma focus device for application in soft X-ray lithography

    International Nuclear Information System (INIS)

    Kalaiselvi, S.M. P.; Tan, T.L.; Talebitaher, A.; Lee, Paul; Rawat, R.S.

    2014-01-01

    The Fast Miniature Plasma Focus (FMPF) device is basically made up of coaxial electrodes with centrally placed anode and six cathode rods surrounding them concentrically. They are enclosed in a vacuum chamber, filled with low pressure operating gas. However, in our experiments, these cathode rods were removed to investigate the influence of them on neon soft X-ray (SXR) and hard X-ray (HXR) emission from the device. On removal of cathode rods, the cathode base plate serves as cathode and the plasma sheath is formed between the anode and the base plate of cathode. Neon was used as the operating gas for our experiments and the FMPF device used is of 235 J energy capacities. The experimental results showed that the FMPF device was able to focus better and the SXR emission efficiency was five times higher without cathode rods than with cathode rods. On the contrary, HXR emission did not vary with and without cathode rods. This observed phenomenon was further cross-checked through imaging of plasma dynamics, with and without cathode rods. FMPF device consists of 4 Pseudo Spark Gap (PSG) switches, which need to operate synchronously to deliver high voltage from capacitors to the anode. It was also seen that, the presence or absence of cathode rods also influence the synchronous operation of PSG switches. It also implies that this is one definite way to optimize the SXR emission from the FMPF device. This study reveals an important finding that, cathode rods play a vital role in the formation of plasma sheath with consequential influence on the radiation emission from plasma focus devices. Enhancement of the X-ray emission from this device is definitely a stepping stone in the realization of this device for industrial applications such as X-ray lithography for semiconductor industries. (author)

  11. A method for measuring the time structure of synchrotron x-ray beams

    International Nuclear Information System (INIS)

    Moses, W.W.; Derenzo, S.E.

    1989-08-01

    We describe a method employing a plastic scintillator coupled to a fast photomultiplier tube to generate a timing pulse from the x-ray bursts emitted from a synchrotron radiation source. This technique is useful for performing synchrotron experiments where detailed knowledge of the timing distribution is necessary, such as time resolved spectroscopy or fluorescence lifetime experiments. By digitizing the time difference between the timing signal generated on one beam crossing with the timing signal generated on the next beam crossing, the time structure of a synchrotron beam can be analyzed. Using this technique, we have investigated the single bunch time structure at the National Synchrotron Light Source (NSLS) during pilot runs in January, 1989, and found that the majority of the beam (96%) is contained in one rf bucket, while the remainder of the beam (4%) is contained in satellite rf buckets preceeding and following the main rf bucket by 19 ns. 1 ref., 4 figs

  12. X-ray micro-beam characterization of a small pixel spectroscopic CdTe detector

    Science.gov (United States)

    Veale, M. C.; Bell, S. J.; Seller, P.; Wilson, M. D.; Kachkanov, V.

    2012-07-01

    A small pixel, spectroscopic, CdTe detector has been developed at the Rutherford Appleton Laboratory (RAL) for X-ray imaging applications. The detector consists of 80 × 80 pixels on a 250 μm pitch with 50 μm inter-pixel spacing. Measurements with an 241Am γ-source demonstrated that 96% of all pixels have a FWHM of better than 1 keV while the majority of the remaining pixels have FWHM of less than 4 keV. Using the Diamond Light Source synchrotron, a 10 μm collimated beam of monochromatic 20 keV X-rays has been used to map the spatial variation in the detector response and the effects of charge sharing corrections on detector efficiency and resolution. The mapping measurements revealed the presence of inclusions in the detector and quantified their effect on the spectroscopic resolution of pixels.

  13. Development of isodose curves for A 6 mv x-ray beam

    Energy Technology Data Exchange (ETDEWEB)

    Hidaytalla, Lamya Abbas [Department of Physics, Faculty of Science, University of Khartoum, Khartoum (Sudan)

    1994-08-01

    In this thesis radiation distribution of 6 Mv x-ray beam in a water phantom is developed. The method is based on a simple empirical equation and the assumption that the x-ray source is a point source. This leads to a simple equation for the calculation and plotting of the isodose curves. the charts obtained for two fields, 6*6 and 12*12 cm{sup 2} show good agreement with the previous data used in the isotope and radiation centre, Khartoum hospital. It is suggested that further development should be carried out by writing a computer program for all the fields. (Author) 14 refs. , 9 tabs. , 34 figs. Also available from the Department of Physics, Faculty of Science, University of Khartoum, Khartoum (SD)

  14. Reduction of variable-truncation artifacts from beam occlusion during in situ x-ray tomography

    DEFF Research Database (Denmark)

    Borg, Leise; Jørgensen, Jakob Sauer; Frikel, Jürgen

    2017-01-01

    Many in situ x-ray tomography studies require experimental rigs which may partially occlude the beam and cause parts of the projection data to be missing. In a study of fluid flow in porous chalk using a percolation cell with four metal bars drastic streak artifacts arise in the filtered...... and artifact-reduction methods are designed in context of FBP reconstruction motivated by computational efficiency practical for large, real synchrotron data. While a specific variable-truncation case is considered, the proposed methods can be applied to general data cut-offs arising in different in situ x-ray...... backprojection (FBP) reconstruction at certain orientations. Projections with non-trivial variable truncation caused by the metal bars are the source of these variable-truncation artifacts. To understand the artifacts a mathematical model of variable-truncation data as a function of metal bar radius and distance...

  15. Building a graphite calorimetry system for the dosimetry of therapeutic x-ray beams

    Energy Technology Data Exchange (ETDEWEB)

    Kim, In Jung; Kim, Byoung Chul; Kim, Joong Hyun; Chung, Jae Pil; Kim, Hyun Moon; Yi, Chul Young [Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of)

    2017-06-15

    A graphite calorimetry system was built and tested under irradiation. The noise level of the temperature measurement system was approximately 0.08 mK (peak to peak). The temperature of the core part rose by approximately 8.6 mK at 800 MU (monitor unit) for 6-MV X-ray beams, and it increased as X-ray energy increased. The temperature rise showed less spread when it was normalized to the accumulated charge, as measured by an external monitoring chamber. The radiation energy absorbed by the core part was determined to have values of 0.798 J/μC, 0.389 J/μC, and 0.352 J/μC at 6 MV, 10 MV, and 18 MV, respectively. These values were so consistent among repeated runs that their coefficient of variance was less than 0.15%.

  16. Calibration of screen-type X-ray films for electron beams

    International Nuclear Information System (INIS)

    Kobayashi, T.; Sato, Y.; Yoshida, K.; Tateyama, N.; Komori, Y.; Nakabayashi, T.; Oyamada, M.; Nishimura, J.

    2002-01-01

    In order to extract the maximum performance of the screen-type X-ray film for the detection of cascade showers in emulsion chambers, we examined the effect of the thickness of the phosphor screen by irradiation with 200 MeV electron beams. The observed data is in agreement with our analytical prediction of the radiative transfer of photons in a phosphor screen. If we use a combination of the specially prepared screen, HR16B, with a phosphor layer of 400 μm and a green-sensitive X-ray film, HA30, the detection threshold energy of cascade showers can be considerably lowered down to 140 GeV. (author)

  17. Calibration of screen-type X-ray films for electron beams

    CERN Document Server

    Kobayashi, T; Yoshida, K; Tateyama, N; Komori, Y; Nakabayashi, T; Oyamada, M; Nishimura, J

    2002-01-01

    In order to extract the maximum performance of the screen-type X-ray film for the detection of cascade showers in emulsion chambers, we examined the effect of the thickness of the phosphor screen by irradiation with 200 MeV electron beams. The observed data is in agreement with our analytical prediction of the radiative transfer of photons in a phosphor screen. If we use a combination of the specially prepared screen, HR16B, with a phosphor layer of 400 mu m and a green-sensitive X-ray film, HA30, the detection threshold energy of cascade showers can be considerably lowered down to 140 GeV. (author)

  18. Design of x-ray diagnostic beam line for a synchrotron radiation source and measurement results

    Energy Technology Data Exchange (ETDEWEB)

    Garg, Akash Deep, E-mail: akash-deep@rrcat.gov.in; Karnewar, A.K.; Ojha, A.; Shrivastava, B.B.; Holikatti, A.C.; Puntambekar, T.A.; Navathe, C.P.

    2014-08-01

    Indus-2 is a 2.5 GeV synchrotron radiation source (SRS) operational at the Raja Ramanna Centre for Advanced Technology (RRCAT) in India. We have designed, developed and commissioned x-ray diagnostic beam line (X-DBL) at the Indus-2. It is based on pinhole array imaging (8–18 keV). We have derived new equations for online measurements of source position and emission angle with pinhole array optics. Measured values are compared with the measurements at an independent x-ray beam position monitor (staggered pair blade monitor) installed in the X-DBL. The measured values are close to the theoretical expected values within ±12 µm (or ±1.5 μrad) for sufficiently wide range of the beam movements. So, beside the beam size and the beam emittance, online information for the vertical position and angle is also used in the orbit steering. In this paper, the various design considerations of the X-DBL and online measurement results are presented.

  19. X-ray beam transfer between hollow fibers for long-distance transport

    International Nuclear Information System (INIS)

    Tanaka, Yoshihito; Matsushita, Ryuki; Shiraishi, Ryutaro; Hasegawa, Takayuki; Ishikawa, Kiyoshi; Sawada, Kei; Kohmura, Yoshiki; Takahashi, Isao

    2016-01-01

    Fiber optics for controlling the x-ray beam trajectory has been examined at the synchrotron facility of SPring-8. Up to now, we have achieved beam deflection by several tens of milli-radian and axis shift of around 75 mm with a 1.5 m-long flexible hollow glass capillary. The achievable beam deflecting angle, axis shift, and timing delay are, in principle, proportional to the length, the square of length and the cube of length, respectively. Thus, for further applications, requiring larger beam shift and pulse delay, longer fibers are indispensable. In order to achieve long-distance transport using the fiber, we thus examined the connection transferring x-rays between fibers in an experimental hutch. The acceptance angle at the input end and the throughput efficiency of the second fiber is consistent with the consideration of the output beam divergence of the first fiber. The enhancement of the transfer efficiency is also discussed for the cases of a closer joint and the use of a refractive lens as a coupler.

  20. X-ray beam transfer between hollow fibers for long-distance transport

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Yoshihito, E-mail: tanaka@sci.u-hyogo.ac.jp; Matsushita, Ryuki; Shiraishi, Ryutaro; Hasegawa, Takayuki; Ishikawa, Kiyoshi [Graduate School of Material Science, University of Hyogo, 3-2-1 Kouto, Kamigori-cho, Sayo-gun, Hyogo 678-1297 (Japan); Sawada, Kei; Kohmura, Yoshiki [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Takahashi, Isao [Department of Physics, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337 Japan (Japan)

    2016-07-27

    Fiber optics for controlling the x-ray beam trajectory has been examined at the synchrotron facility of SPring-8. Up to now, we have achieved beam deflection by several tens of milli-radian and axis shift of around 75 mm with a 1.5 m-long flexible hollow glass capillary. The achievable beam deflecting angle, axis shift, and timing delay are, in principle, proportional to the length, the square of length and the cube of length, respectively. Thus, for further applications, requiring larger beam shift and pulse delay, longer fibers are indispensable. In order to achieve long-distance transport using the fiber, we thus examined the connection transferring x-rays between fibers in an experimental hutch. The acceptance angle at the input end and the throughput efficiency of the second fiber is consistent with the consideration of the output beam divergence of the first fiber. The enhancement of the transfer efficiency is also discussed for the cases of a closer joint and the use of a refractive lens as a coupler.

  1. DOE/DMS workshop on future synchrotron VUV and x-ray beam Lines

    International Nuclear Information System (INIS)

    Green, P.H.

    1992-03-01

    This document contains an overview of the participating DOE Laboratory beam line interests and the projected science to be addressed on these beam lines, both at new and existing synchrotron facilities. The scientific programs associated with present and planned synchrotron research by DOE Laboratories are discussed in chapters titled ''VUV and Soft X-Ray Research'' and ''Hard X-Ray Research.'' This research encompasses a broad range of the nation's scientific and technical research needs from fundamental to applied, in areas including environmental, biological, and physical sciences; new materials; and energy-related technologies. The projected cost of this proposed construction has been provided in tabular form using a uniform format so that anticipated DOE and outside funding agency contributions for construction and for research and development can be determined. The cost figures are, of course, subject to uncertainties of detailed design requirements and the availability of facility-designed generic components and outside vendors. The report also contains a compendium (as submitted by the beam line proposers) of the design capabilities, the anticipated costs, and the scientific programs of projected beam line construction at the four synchrotron facilities. A summary of the projected cost of these beam lines to be requested of DOE is compiled

  2. X-ray and neutron emission studies in a new Filippov type plasma focus

    Energy Technology Data Exchange (ETDEWEB)

    Babazadeh, A.R.; Banoushi, A. [Technical University of Amirkabir, Tehran (Iran, Islamic Republic of). Dept. of Physics; Roshan, M.V.; Habibi, H.; Nasiry, A.; Memarzadeh, M.; Lamehi, M.; Kiai, S.M. Sadat [Atomic Energy Organization of Iran (AEOI), Tehran (Iran, Islamic Republic of). Nuclear Fusion Research Center

    2002-03-01

    We have performed experimental comparative studies of the X-ray and neutron emission generated by the new Filippov-type plasma focus 'Dena', (90 kJ, 25 kV, 288{mu}F) in the pressure range of 0.6-1 torr. Time-integrated and time-resolved detectors, together with an X-ray pin-hole camera, along with a Be filter of 10{mu}m thickness have been used. For a working gas of neon and a at insert anode, the maximum soft and hard X-rays (SXR-HXR) yield obtained was 16 V and 1.5 V/shot over a 4{pi} solid angle, respectively, for a charging voltage range of 16-20 kV. As for the argon gas, the similar results such as 3.5 and 2 V/shot have been found, leading to a total conversion efficiency of X-ray emission of 0.09 % (for neon) and 0.03 % (for argon) of the stored energy. These efficiencies have been improved by the employment of a conic insert anode up to 0.4% and 0.1%. With deuterium puffing gas and a at insert anode, the maximum emission yield has been found to be 2.5 V for SXR and 1 V for HXR/shot which produce an ultimate emission profile width (FWHM) of 70-90 ns for X-rays and neutrons, giving rise to a maximum neutron yield of 1.2 x 10{sup 9}. Nevertheless, the maximum yield has been increased up to 5.5 times with the conic insert anode. In order to increase the neutron yield, we have introduced a krypton admixture to the deuterium filling gas and found that, for a krypton pressure of about 0.1 torr, the neutron yield increases by a factor of 3.5 for the flat insert and 1.5 for the conic insert anodes. (author)

  3. The development of a postal method to assess X-ray beam parameters and image quality in dental radiology

    International Nuclear Information System (INIS)

    Fenton, D.M.

    1994-10-01

    Intraoral radiographs are an extremely valuable diagnostic tool in dentistry. Radiography permits the early detection and diagnosis of dental disease and consequently is used extensively. However, public concern about radiation exposure has increased in recent times. This concern is reflected in national and international law, to the extent that, the basic principles of radiological protection, that is, justification, optimisation and dose limitation are written into law. Furthermore, in Ireland, the regulations, as outlined in the Code of Practice for Radiological Protection in Dentistry, require intraoral dental X-ray machines to perform to certain standards. A report of a direct survey of 164 intraoral dental X-ray machines is given in this study. The survey covered mechanical, electrical as well as radiation safety. Inadequacies with respect to focus to skin distance and timer accuracy were found in 45% and 42% of the machines surveyed. Ninety eight machines were assessed for electrical safety in which 48% were found to be unsafe. The results indicate that a complete assessment of the performance of dental X-ray units in Ireland is required. However, as there are in excess of 800 dental X-ray machines located throughout the country, such an assessment would be very costly for the regulatory authority. The development of a postal method for the assessment of the performance of dental X-ray machines is described in this study. This postal method provides information on the kV, total filtration, beam width and timer linearity and is undertaken by means of a penetrameter and film envelopes for exposure to the X-ray set under examination, together with a questionnaire that requests information on environment in which the machine is located. Using this method an accuracy of +-5% of the actual value was achieved in the measurement of kVp. The penetrameter was also used to assess whether or not the filtration of a particular machine complies with the regulations. This

  4. Inspection of single CdSe nanowires by use of micro-focused X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Kurtulus, Oezguel [Dogus University, Istanbul (Turkey); Li, Zhen [University of Queensland, Brisbane (Australia); Arezki, Bahia; Biermanns, Andreas; Pietsch, Ullrich [University of Siegen (Germany)

    2010-07-01

    The morphology of CdSe nanowires (NW) can easily be controlled by various growth methods. In this study, CdSe NWs are prepared by solution-liquid-solid (SLS) approach providing needle-shaped wires of about 60nm in diameter and several microns in length. To make X-ray single NW inspection possible, the NWs were dispersed in toluene and hexadecylamine, homogenized by centrifugation and finally spin-coated on silicon substrate. SEM images revealed that the NWs are randomly oriented with length axis parallel to the substrate. However, at selected areas, the distance between neighboured NWs is in the order of one micron. These samples were investigated by X-ray diffraction using a 300 nm x 600 nm micro-focus at beamline ID1 of ESRF. Diffraction from 110W/2-20ZB basal plane was selected for single nanowire inspection. In order to measure various single objects subsequently, the sample was laterally scanned through the beam keeping the diffraction angle fixed. It was observed that the individual NWs differ slightly in peak position and peak width. From powder diffraction, it is known that NWs consist of an admixture of a wurtzite (W) and zinc-blende (ZB) structure units and the coherent illumination of sample by the micro-focus enables to visualize these zinc-blende and wurzite units separated by stacking faults.

  5. The APS x-ray undulator photon beam position monitor and tests at CHESS and NSLS

    International Nuclear Information System (INIS)

    Shu, D.; Rodricks, B.; Barraza, J.; Sanchez, T.; Kuzay, T.M.

    1992-01-01

    The advent of third generation synchrotron radiation sources, like the Advanced Photon Source (APS), will provide significant increases in brilliance over existing synchrotron sources. The APS x-ray undulators will increase the brilliance in the 3-40 KeV range by several orders of magnitude. Thus, the design of the photon beam position monitor is a challenging engineering task. The beam position monitors must withstand the high thermal load, be able to achieve sub-micron spatial resolution while maintaining their stability, and be compatible with both undulators and wigglers. A preliminary APS prototype photon beam position monitor consisting of a CVD-diamond-based, tungsten-coated blade was tested on the APS/CHESS undulator at the Cornell High Energy Synchrotron Radiation Source (CHESS) and on the NSLS X-13 undulator beamline. Results from these tests, as well as the design of this prototype APS photon beam position monitor, will be discussed in this paper

  6. The APS X-ray undulator photon beam position monitor and tests at CHESS and NSLS

    International Nuclear Information System (INIS)

    Shu, D.; Rodricks, B.; Barraza, J.; Sanchez, T.; Kuzay, T.M.

    1992-01-01

    The advent of thirs generation synchrotron sources, like the Advanced Photon Source (APS), will provide significant increases in brilliance over existing synchrotron sources. The APS X-ray undulators will increase the brilliance in the 3-40 keV range by several orders of magnitude. Thus, the design of the photon beam position monitor is a challenging engineering task. The beam position monitors must withstand the high thermal load, be able to achieve submicron spatial resolution while maintaining their stability, and be compatible with both undulators and wigglers. A preliminary APS prototype photon beam position monitor consisting of a CVD-diamond-based, tungsten-coated blade was tested on the APS/CHESS undulator at the Cornell High Energy Synchrotron Radiation Source (CHESS) and on the NSLS X-13 undulator beamline. Results from these tests, as well as the design of this prototype APS photon beam position monitor, will be discussed in this paper. (orig.)

  7. On beam quality and stopping power ratios for high-energy x-rays

    International Nuclear Information System (INIS)

    Johnsson, S.A.; Ceberg, C.P.; Knoeoes, T.; Nilsson, P.

    2000-01-01

    The aim of this work is to quantitatively compare two commonly used beam quality indices, TPR(20/10) and %dd(10) x , with respect to their ability to predict stopping power ratios (water to air), s w,air , for high-energy x-rays. In particular, effects due to a varied amount of filtration of the photon beam will be studied. A new method for characterizing beam quality is also presented, where the information we strive to obtain is the moments of the spectral distribution. We will show how the moments enter into a general description of the transmission curve and that it is possible to correlate the moments to s w,air with a unique and simple relationship. Comparisons with TPR(20/10) and %dd(10) x show that the moments are well suited for beam quality specification in terms of choosing the correct s w,air . (author)

  8. Investigations of the phase transition in V3O5 using energy dispersive X-ray diffraction and synchrotron radiation white beam X-ray topography

    International Nuclear Information System (INIS)

    Asbrink, S.; Gerward, L.; Staun Olsen, J.

    1985-01-01

    The reversible first order phase transition in V 3 O 5 at T t =155 0 C has been studied using a specially constructed oven, where the temperature can be kept constant within a few hundredths of a degree for several hours. Energy dispersive diffraction measurements have beem made in a temperature region around the phase transition with the fixed crystal method and the θ/2θ scanning method. White beam X-ray topographs have been obtained from the same crystal in the same temperature region using synchrotron radiation. The integrated intensities of the strong h 0 0 reflections show anomalies that are correlated with the corresponding X-ray topographs. Thus, an unexpected increase of crystal perfection is observed a few hundredths of a degree below T t . The energy dependence of the intensity maximum at T t for strong reflections has been determined and semi-quantitatively explained on the basis of extinction theory. (orig.)

  9. Smart x-ray beam position monitor system for the Advanced Photon Source

    International Nuclear Information System (INIS)

    Shu, D.; Kuzay, T.

    1996-01-01

    In third-generation synchrotron radiation sources, such as the Advanced Photon Source (APS), the sensitivity and reliability requirements for the x-ray beam position monitors (XBPMs) are much higher than for earlier systems. Noise and contamination signals caused by radiation emitted from the bending magnet become a major problem. The regular XBPM calibration process can only provide signal correction for one set of conditions for the insertion devices (ID). During normal operation, parameters affecting the ID-emitted beam, such as the gap of the ID magnets and the beam current, are the variables. A new smart x-ray beam position monitor system (SBPM) has been conceived and designed for the APS. It has a built in self-learning structure with EEPROM memory that is large enough to open-quote open-quote remember close-quote close-quote a complete set of calibration data covering all the possible operating conditions. During the self-learning mode, the monitor system initializes a series of automatic scan motions with information for different ID setups and records them into the database array. During normal operation, the SBPM corrects the normalized output according to the ID setup information and the calibration database. So that, with this novel system, the SBPM is always calibrating itself with the changing ID set up conditions. copyright 1996 American Institute of Physics

  10. Evaluation of the spectral distribution of X-ray beams from measurements on the scattered radiation

    International Nuclear Information System (INIS)

    Casnati, E.; Baraldi, C.

    1980-01-01

    Most of the phenomena activated by photons with energies below 100 keV show an apparent or real dependence on the quantum energy. Therefore, knowledge of the beam energy characteristics is of primary importance for interpretation of the irradiation results. The greatest difficulty arises from the high flux density of the beams usually employed which does not allow direct measurements of the beam. A method was developed which permits evaluation of the spectral distribution of the X-ray beam from a spectrometric measurement of the radiation scattered by a thin foil of a suitable metal. This makes possible a new and more rational approach to the measurement of X-rays in the energy range where the interaction parameters show a large photon energy dependence. The corrections required by the presence of some collateral effects, among which the most important is the coexistence of the coherent and incoherent scattering, must be evaluated. The knowledge of the spectral distribution is of immediate usefulness for studies of radiation damage in biological and other materials, for the calibration of radiation measuring instruments and for the improvement of the radiological instrumentation response which contributes to reducing the patient's dose. (H.K.)

  11. Scattered hard X-ray and γ-ray generation from a chromatic electron beam

    Energy Technology Data Exchange (ETDEWEB)

    Coleman, J. E. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Welch, D. R.; Miller, C. L. [Voss Scientific, Albuquerque, New Mexico 87108 (United States)

    2015-11-14

    An array of photon diagnostics has been deployed on a high power relativistic electron beam diode. Electrons are extracted through a 17.8 cm diode from the surface discharge of a carbon fiber velvet cathode with a nominal diode voltage of 3.8 MV. <10% of the 100 ns electron pulse is composed of off energy electrons (1–3 MeV) accelerated during the rise and fall of the pulse that impact the stainless steel beam pipe and generate a Bremsstrahlung spectrum of 0.1–3 MeV photons with a total count of 10{sup 11}. The principal objective of these experiments is to quantify the electron beam dynamics and spatial dynamics of the hard X-ray and γ-ray flux generated in the diode region. A qualitative comparison of experimental and calculated results are presented, including time and energy resolved electron beam propagation and scattered photon measurements with X-ray PIN diodes and a photomultiplier tube indicating a dose dependence on the diode voltage >V{sup 4} and detected photon counts of nearly 10{sup 6} at a radial distance of 1 m which corresponds to dose ∼40 μrad at 1 m.

  12. Detection of coherent X-ray transition radiation and its application to beam diagnostics

    International Nuclear Information System (INIS)

    Piestrup, M.A.; Boyers, D.G.; Pincus, C.I.; Li Qiang; Moran, M.J.; Bergstrom, J.C.; Caplan, H.S.; Silzer, R.M.; Skopik, D.M.; Rothbart, G.B.

    1989-01-01

    We investigate the use of coherent X-ray transition radiation to measure the energy of ultra-relativistic charged particles. This can be used for beam diagnostics for both high-repetition-rate and single-pulse, high-current accelerators. The research also has possible applications for the detection and identification of these particles. By selecting foil thickness and spacing, it is possible to design radiators whose angle of emission varies radically over a range of charged particle energies. We have constructed three coherent radiators and tested them at two accelerators using electron beam energies ranging from 50 to 228 MeV. Soft X-ray emission (1-3 keV) was emitted in a circularly symmetrical annulus with half-angle divergence of 2.5-9.0 mrad. The angle of peak emission was found to increase with electron-beam energy, in contrast to the incoherent case for which the angle of emission varies inversely with electron-beam energy. (orig.)

  13. Beam hardening: Analytical considerations of the effective attenuation coefficient of x-ray tomography

    International Nuclear Information System (INIS)

    Alles, J.; Mudde, R. F.

    2007-01-01

    Polychromatic x-ray beams traveling though material are prone to beam hardening, i.e., the high energy part of the incident spectrum gets over represented when traveling farther into the material. This study discusses the concept of a mean attenuation coefficient in a formal way. The total energy fluence is one-to-one related to the traveled distance in case of a polychromatic beam moving through a given, inhomogeneous material. On the basis of this one-to-one relation, it is useful to define a mean attenuation coefficient and study its decrease with depth. Our results are based on a novel parametrization of the energy dependence of the attenuation coefficient that allows for closed form evaluation of certain spectral integrals. This approach underpins the ad hoc semianalytical expressions given in the literature. An analytical model for the average attenuation coefficient is proposed that uses a simple fit of the attenuation coefficient as a function of the photon energy as input. It is shown that a simple extension of this model gives a rather good description of beam hardening for x-rays traveling through water

  14. Correlation of photon beam motion with vacuum chamber cooling on the NSLS x-ray ring

    International Nuclear Information System (INIS)

    Johnson, E.D.; Fauchet, A.M.; Zhang, Xiaohao.

    1991-01-01

    The NSLS X-ray ring exhibits a direct correlation between photon beam motion, and distortion of the ring vacuum chamber induced by fluctuations in the cooling system. We have made long term measurements of photon beam vertical position, accelerator vacuum chamber motion, process water temperatures, and angular motions of the magnets around one superperiod of the NSLS x-ray ring. Short term transients in water temperature cause deflection of the ring vacuum chamber which have in turn been shown to induce very small angular rotations of the magnets, on the order of 10 micro-radians. A larger and more difficult to correct effect is the drift in beam position over the course of a fill. This problem has been shown to be related to the thermal gradients that develop across the vacuum chamber which, as a consequence of the configuration of the chamber cooling, depend upon stored current. Orbit simulations based upon the measured rotations are in agreement with the observed beam motions, and reveal that certain patterns of correlated motions of the magnets can produce much larger errors than random motion or concerted motion of all the magnets. During the course of these measurements global orbit feedback was installed, and found to significantly reduce the orbit errors which could not be corrected at their source

  15. Thermometric- and Acoustic-Based Beam Power Monitor for Ultra-Bright X-Rays

    International Nuclear Information System (INIS)

    2010-01-01

    A design for an average beam power monitor for ultra-bright X-ray sources is proposed that makes simultaneous use of calorimetry and radiation acoustics. Radiation incident on a solid target will induce heating and ultrasonic vibrations, both of which may be measured to give a fairly precise value of the beam power. The monitor is intended for measuring ultra-bright Free-Electron Laser (FEL) X-ray beams, for which traditional monitoring technologies such as photo-diodes or scintillators are unsuitable. The monitor consists of a Boron Carbide (B 4 C) target designed to absorb most of the incident beam's energy. Resistance temperature detectors (RTD) and piezoelectric actuators are mounted on the outward faces of the target to measure the temperature changes and ultrasonic vibrations induced by the incident beam. The design was tested using an optical pulsed beam (780 nm, 120 and 360 Hz) from a Ti:sapphire oscillator at several energies between 0.8 and 2.6 mJ. The RTDs measured an increase in temperature of about 10 K over a period of several minutes. The piezoelectric sensors recorded ringing acoustic oscillations at 580 ± 40 kHz. Most importantly, the amplitude of the acoustic signals was observed to scale linearly with beam power up to 2 mJ of pulse energy. Above this pulse energy, the vibrational signals became nonlinear. Several causes for this nonlinearity are discussed, including amplifier saturation and piezoelectric saturation. Despite this nonlinearity, these measurements demonstrate the feasibility of such a beam power measurement device. The advantage of two distinct measurements (acoustic and thermometric) provides a useful method of calibration that is unavailable to current LCLS diagnostics tools.

  16. MeV single-ion beam irradiation of mammalian cells using the Surrey vertical nanobeam, compared with broad proton beam and X-ray irradiations

    Energy Technology Data Exchange (ETDEWEB)

    Prakrajang, K. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Faculty of Science, Maejo University, Chiang Mai 50290 (Thailand); Jeynes, J.C.G.; Merchant, M.J.; Kirkby, K.; Kirkby, N. [Surrey Ion Beam Center, Faculty of Engineering and Physical Science, University of Surrey, Guildford Surrey, GU2 7XH (United Kingdom); Thopan, P. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Yu, L.D., E-mail: yuld@fnrf.science.cmu.ac.th [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand)

    2013-07-15

    Highlights: •Recently completed nanobeam at the Surrey Ion Beam Centre was used. •3.8-MeV single and broad proton beams irradiated Chinese hamster cells. •Cell survival curves were measured and compared with 300-kV X-ray irradiation. •Single ion irradiation had a lower survival part at ultra-low dose. •It implies hypersensitivity, bystander effect and cell cycle phase of cell death. -- Abstract: As a part of a systematic study on mechanisms involved in physical cancer therapies, this work investigated response of mammalian cells to ultra-low-dose ion beam irradiation. The ion beam irradiation was performed using the recently completed nanobeam facility at the Surrey Ion Beam Centre. A scanning focused vertical ion nano-beam was applied to irradiate Chinese hamster V79 cells. The V79 cells were irradiated in two different beam modes, namely, focused single ion beam and defocused scanning broad ion beam of 3.8-MeV protons. The single ion beam was capable of irradiating a single cell with a precisely controlled number of the ions to extremely low doses. After irradiation and cell incubation, the number of surviving colonies as a function of the number of the irradiating ions was measured for the cell survival fraction curve. A lower survival for the single ion beam irradiation than that of the broad beam case implied the hypersensitivity and bystander effect. The ion-beam-induced cell survival curves were compared with that from 300-kV X-ray irradiation. Theoretical studies indicated that the cell death in single ion irradiation mainly occurred in the cell cycle phases of cell division and intervals between the cell division and the DNA replication. The success in the experiment demonstrated the Surrey vertical nanobeam successfully completed.

  17. Improving x-ray fluorescence signal for benchtop polychromatic cone-beam x-ray fluorescence computed tomography by incident x-ray spectrum optimization: a Monte Carlo study.

    Science.gov (United States)

    Manohar, Nivedh; Jones, Bernard L; Cho, Sang Hyun

    2014-10-01

    To develop an accurate and comprehensive Monte Carlo (MC) model of an experimental benchtop polychromatic cone-beam x-ray fluorescence computed tomography (XFCT) setup and apply this MC model to optimize incident x-ray spectrum for improving production/detection of x-ray fluorescence photons from gold nanoparticles (GNPs). A detailed MC model, based on an experimental XFCT system, was created using the Monte Carlo N-Particle (MCNP) transport code. The model was validated by comparing MC results including x-ray fluorescence (XRF) and scatter photon spectra with measured data obtained under identical conditions using 105 kVp cone-beam x-rays filtered by either 1 mm of lead (Pb) or 0.9 mm of tin (Sn). After validation, the model was used to investigate the effects of additional filtration of the incident beam with Pb and Sn. Supplementary incident x-ray spectra, representing heavier filtration (Pb: 2 and 3 mm; Sn: 1, 2, and 3 mm) were computationally generated and used with the model to obtain XRF/scatter spectra. Quasimonochromatic incident x-ray spectra (81, 85, 90, 95, and 100 keV with 10 keV full width at half maximum) were also investigated to determine the ideal energy for distinguishing gold XRF signal from the scatter background. Fluorescence signal-to-dose ratio (FSDR) and fluorescence-normalized scan time (FNST) were used as metrics to assess results. Calculated XRF/scatter spectra for 1-mm Pb and 0.9-mm Sn filters matched (r ≥ 0.996) experimental measurements. Calculated spectra representing additional filtration for both filter materials showed that the spectral hardening improved the FSDR at the expense of requiring a much longer FNST. In general, using Sn instead of Pb, at a given filter thickness, allowed an increase of up to 20% in FSDR, more prominent gold XRF peaks, and up to an order of magnitude decrease in FNST. Simulations using quasimonochromatic spectra suggested that increasing source x-ray energy, in the investigated range of 81-100 ke

  18. The Focusing Optics X-ray Solar Imager Small Explorer Concept Mission

    Science.gov (United States)

    Christe, Steven; Shih, Albert Y.; Dennis, Brian R.; Glesener, Lindsay; Krucker, Sam; Saint-Hilaire, Pascal; Gubarev, Mikhail; Ramsey, Brian

    2016-05-01

    We present the FOXSI (Focusing Optics X-ray Solar Imager) small explorer (SMEX) concept, a mission dedicated to studying particle acceleration and energy release on the Sun. FOXSI is designed as a 3-axis stabilized spacecraft in low-Earth orbit making use of state-of-the-art grazing incidence focusing optics combined withpixelated solid-state detectors, allowing for direct imaging of solar X-rays. The current design being studied features multiple telescopes with a 14 meter focal length enabled by a deployable boom.FOXSI will observe the Sun in the 3-100 keV energy range. The FOXSI imaging concept has already been tested on two sounding rocket flights, in 2012 and 2014 and on the HEROES balloon payload flight in 2013. FOXSI will image the Sun with an angular resolution of 5'', a spectral resolution of 0.5 keV, and sub-second temporal resolution. FOXSI is a direct imaging spectrometer with high dynamic range and sensitivity and will provide a brand-new perspective on energy release on the Sun. We describe the mission and its science objectives.

  19. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... current x-ray images for diagnosis and disease management. top of page How is the procedure performed? ... standards used by radiology professionals. Modern x-ray systems have very controlled x-ray beams and dose ...

  20. Central X-ray beam correction of radiographic acetabular cup measurement after THA: an experimental study.

    Science.gov (United States)

    Schwarz, T; Weber, M; Wörner, M; Renkawitz, T; Grifka, J; Craiovan, B

    2017-05-01

    Accurate assessment of cup orientation on postoperative radiographs is essential for evaluating outcome after THA. However, accuracy is impeded by the deviation of the central X-ray beam in relation to the cup and the impossibility of measuring retroversion on standard pelvic radiographs. In an experimental trial, we built an artificial cup holder enabling the setting of different angles of anatomical anteversion and inclination. Twelve different cup orientations were investigated by three examiners. After comparing the two methods for radiographic measurement of the cup position developed by Lewinnek and Widmer, we showed how to differentiate between anteversion and retroversion in each cup position by using a second plane. To show the effect of the central beam offset on the cup, we X-rayed a defined cup position using a multidirectional central beam offset. According to Murray's definition of anteversion and inclination, we created a novel corrective procedure to balance measurement errors caused by deviation of the central beam. Measurement of the 12 different cup positions with the Lewinnek's method yielded a mean deviation of [Formula: see text] (95 % CI 1.3-2.3) from the original cup anteversion. The respective deviation with the Widmer/Liaw's method was [Formula: see text] (95 % CI 2.4-4.0). In each case, retroversion could be differentiated from anteversion with a second radiograph. Because of the multidirectional central beam offset ([Formula: see text] cm) from the acetabular cup in the cup holder ([Formula: see text] anteversion and [Formula: see text] inclination), the mean absolute difference for anteversion was [Formula: see text] (range [Formula: see text] to [Formula: see text] and [Formula: see text] (range [Formula: see text] to [Formula: see text] for inclination. The application of our novel mathematical correction of the central beam offset reduced deviation to a mean difference of [Formula: see text] for anteversion and [Formula: see text

  1. Philips high tension generator (x-ray machine) testing for baby ebm (electron beam machine) project

    International Nuclear Information System (INIS)

    Norman Awalludin; Leo Kwee Wah; Abu Bakar Mhd Ghazali

    2005-01-01

    This paper describes the test of the HT system (from X-ray machine) for usage of the mini EBM (Electron Beam Machine). It consists the procedures of the installation, the safety procedures when deals with HT, modification of the system for testing purpose and the technique/method for testing the HT system. As a result, the voltage for the HT system and the electron gun (filament) current can be measured. Based on the results, suitability of the machine for baby EBM could be confirmed. (Author)

  2. Computer simulations of X-ray six-beam diffraction in a perfect silicon crystal. I

    Czech Academy of Sciences Publication Activity Database

    Kohn, V.G.; Khikhlukha, Danila

    2016-01-01

    Roč. 72, May (2016), s. 349-356 ISSN 2053-2733 R&D Projects: GA MŠk EF15_008/0000162; GA MŠk ED1.1.00/02.0061 Grant - others:ELI Beamlines(XE) CZ.02.1.01/0.0/0.0/15_008/0000162; ELI Beamlines(XE) CZ.1.05/1.1.00/02.0061 Institutional support: RVO:68378271 Keywords : X-ray diffraction * silicon crystal * six-beam diffraction * section topography * computer simulations Subject RIV: BL - Plasma and Gas Discharge Physics OBOR OECD: Fluids and plasma physics (including surface physics) Impact factor: 5.725, year: 2016

  3. Image covariance and lesion detectability in direct fan-beam x-ray computed tomography.

    Science.gov (United States)

    Wunderlich, Adam; Noo, Frédéric

    2008-05-21

    We consider noise in computed tomography images that are reconstructed using the classical direct fan-beam filtered backprojection algorithm, from both full- and short-scan data. A new, accurate method for computing image covariance is presented. The utility of the new covariance method is demonstrated by its application to the implementation of a channelized Hotelling observer for a lesion detection task. Results from the new covariance method and its application to the channelized Hotelling observer are compared with results from Monte Carlo simulations. In addition, the impact of a bowtie filter and x-ray tube current modulation on reconstruction noise and lesion detectability are explored for full-scan reconstruction.

  4. Sampling conditions of the three dimensional (3D) fan beam X ray transform

    International Nuclear Information System (INIS)

    Desbat, L.; Roux, S.; Grangeat, P.; Koenig, A.

    2003-01-01

    We give the sampling conditions of the 3 D fan beam X ray transform (3.D.F.B.X.R.T.). The motivation of this work lie in the fact that helical tomography with a single detector line is simply a sampling of this transform under the helical constraint. we give a precise description of the geometry of the essential support of Fourier transform of the 3.D.F.B.X.R.T. and we show how to derive efficient sampling. (N.C.)

  5. A novel process control method for a TT-300 E-Beam/X-Ray system

    Science.gov (United States)

    Mittendorfer, Josef; Gallnböck-Wagner, Bernhard

    2018-02-01

    This paper presents some aspects of the process control method for a TT-300 E-Beam/X-Ray system at Mediscan, Austria. The novelty of the approach is the seamless integration of routine monitoring dosimetry with process data. This allows to calculate a parametric dose for each production unit and consequently a fine grain and holistic process performance monitoring. Process performance is documented in process control charts for the analysis of individual runs as well as historic trending of runs of specific process categories over a specified time range.

  6. Image covariance and lesion detectability in direct fan-beam x-ray computed tomography

    International Nuclear Information System (INIS)

    Wunderlich, Adam; Noo, Frederic

    2008-01-01

    We consider noise in computed tomography images that are reconstructed using the classical direct fan-beam filtered backprojection algorithm, from both full- and short-scan data. A new, accurate method for computing image covariance is presented. The utility of the new covariance method is demonstrated by its application to the implementation of a channelized Hotelling observer for a lesion detection task. Results from the new covariance method and its application to the channelized Hotelling observer are compared with results from Monte Carlo simulations. In addition, the impact of a bowtie filter and x-ray tube current modulation on reconstruction noise and lesion detectability are explored for full-scan reconstruction

  7. Standard X ray beams for calibration of dosemeters used in radiation protection practice

    International Nuclear Information System (INIS)

    Pernicka, F.; Michalik, V.

    1992-01-01

    Kerma in air is a widely used reference quantity specified by different calibration laboratories. Calibration of dosemeters used for individual and environmental monitoring requires a knowledge of conversion coefficients between the air kerma and an appropriate protection quantity. These were determined for sets of standard X ray beams using measured spectral distributions, calculated mean energies and effective energies obtained from HVLs measured by an ionisation chamber. There is a good agreement among these three approaches for energies down to 60-70 keV. For lower energies one can expect differences up to 10% if the coefficients are determined from the mean or effective energy instead from the spectral distribution. (author)

  8. Effect of area x-ray beam equalization on image quality and dose in digital mammography

    Energy Technology Data Exchange (ETDEWEB)

    Wong, Jerry; Xu Tong; Husain, Adeel; Le, Huy; Molloi, Sabee [Department of Radiological Sciences, University of California, Irvine, CA 92697 (United States)

    2004-08-21

    In mammography, thick or dense breast regions persistently suffer from reduced contrast-to-noise ratio (CNR) because of degraded contrast from large scatter intensities and relatively high noise. Area x-ray beam equalization can improve image quality by increasing the x-ray exposure to under-penetrated regions without increasing the exposure to other breast regions. Optimal equalization parameters with respect to image quality and patient dose were determined through computer simulations and validated with experimental observations on a step phantom and an anthropomorphic breast phantom. Three parameters important in equalization digital mammography were considered: attenuator material (Z = 13-92), beam energy (22-34 kVp) and equalization level. A Mo/Mo digital mammography system was used for image acquisition. A prototype 16 x 16 piston driven equalization system was used for preparing patient-specific equalization masks. Simulation studies showed that a molybdenum attenuator and an equalization level of 20 were optimal for improving contrast, CNR and figure of merit (FOM = CNR{sup 2}/dose). Experimental measurements using these parameters showed significant improvements in contrast, CNR and FOM. Moreover, equalized images of a breast phantom showed improved image quality. These results indicate that area beam equalization can improve image quality in digital mammography.

  9. Pulse-periodic generation of supershort avalanche electron beams and X-ray emission

    Science.gov (United States)

    Baksht, E. Kh.; Burachenko, A. G.; Erofeev, M. V.; Tarasenko, V. F.

    2014-05-01

    Pulse-periodic generation of supershort avalanche electron beams (SAEBs) and X-ray emission in nitrogen, as well as the transition from a single-pulse mode to a pulse-periodic mode with a high repetition frequency, was studied experimentally. It is shown that, in the pulse-periodic mode, the full width at halfmaximum of the SAEB is larger and the decrease rate of the gap voltage is lower than those in the single-pulse mode. It is found that, when the front duration of the voltage pulse at a nitrogen pressure of 90 Torr decreases from 2.5 to 0.3 ns, the X-ray exposure dose in the pulse-periodic mode increases by more than one order of magnitude and the number of SAEB electrons also increases. It is shown that, in the pulse-periodic mode of a diffuse discharge, gas heating in the discharge gap results in a severalfold increase in the SAEB amplitude (the number of electrons in the beam). At a generator voltage of 25 kV, nitrogen pressure of 90 Torr, and pulse repetition frequency of 3.5 kHz, a runaway electron beam was detected behind the anode foil.

  10. X-ray examination apparatus

    NARCIS (Netherlands)

    2000-01-01

    The invention relates to an X-ray apparatus which includes an adjustable X-ray filter. In order to adjust an intensity profile of the X-ray beam, an X-ray absorbing liquid is transported to filter elements of the X-ray filter. Such transport is susceptible to gravitational forces which lead to an

  11. X-ray convergent beam pattern simulation using the Moodie-Wagenfeld equations: 3-beam Laue case

    International Nuclear Information System (INIS)

    Liu, L.; Goodman, P.

    1998-01-01

    Pattern simulations for 3-beam X-ray diffraction are presented, by multi-slice calculations based on Moodie and Wagenfeld's formulation of the X-ray equations, which factorise Maxwell's equations into Dirac format, using circular-polarisation bases. The results are presented in the form of convergent-beam patterns for each diffraction order, using experience gained from CBED (convergent beam electron diffraction) and LACBED (large-angle CBED), since this displays the results in the most compact form. The acronym CBXRAD (convergent-beam X-ray-diffraction) is used for these patterns. Although optics required for the complete patterns is not currently available, capillary focussing is undergoing rapid development, and our simulations define critical angular ranges within reach of current designs. Simulations for light and heavy-atoms structures belonging to the enantiomorphic space-group pair P3 1 21 and P3 2 21, provide clear evidence of chiral interaction between radiation and structure, highlighting divergences from the well studied CBED pattern symmetries. MoKα 1 and TaKα 1 wavelengths were used to minimise absorption for the two structures respectively, although 'anomalous absorption' is always important due to the large thicknesses required (up to 20 mm)

  12. Investigation on the properties of a laminar grating as a soft x-ray beam splitter

    International Nuclear Information System (INIS)

    Liu Ying; Fuchs, Hans-Joerg; Liu Zhengkun; Chen Huoyao; He Shengnan; Fu Shaojun; Kley, Ernst-Bernhard; Tuennermann, Andreas

    2010-01-01

    Laminar-type gratings as soft x-ray beam splitters for interferometry are presented. Gold-coated grating beam splitters with 1000 lines/mm are designed for grazing incidence operation at 13.9nm. They are routinely fabricated using electron beam lithography and ion etching techniques. The laminar grating is measured to have almost equal absolute efficiencies of about 20% in the zeroth and -1st orders, which enables a fringe visibility up to 0.99 in the interferometer. The discrepancy of the grating profiles between the optimized theoretical and the experimental results is analyzed according to the comparison of the optimized simulation results and the measurement realization of the grating efficiencies. By a precise control of the grating profile, the grating efficiency in the -1st order and the fringe visibility could be improved to 25% and 1, respectively.

  13. A one-dimensional ion beam figuring system for x-ray mirror fabrication

    International Nuclear Information System (INIS)

    Idir, Mourad; Huang, Lei; Bouet, Nathalie; Kaznatcheev, Konstantine; Vescovi, Matthew; Lauer, Ken; Conley, Ray; Rennie, Kent; Kahn, Jim; Nethery, Richard; Zhou, Lin

    2015-01-01

    We report on the development of a one-dimensional Ion Beam Figuring (IBF) system for x-ray mirror polishing. Ion beam figuring provides a highly deterministic method for the final precision figuring of optical components with advantages over conventional methods. The system is based on a state of the art sputtering deposition system outfitted with a gridded radio frequency inductive coupled plasma ion beam source equipped with ion optics and dedicated slit developed specifically for this application. The production of an IBF system able to produce an elongated removal function rather than circular is presented in this paper, where we describe in detail the technical aspect and present the first obtained results

  14. A one-dimensional ion beam figuring system for x-ray mirror fabrication

    Energy Technology Data Exchange (ETDEWEB)

    Idir, Mourad, E-mail: midir@bnl.gov; Huang, Lei; Bouet, Nathalie; Kaznatcheev, Konstantine; Vescovi, Matthew; Lauer, Ken [NSLS-II, Brookhaven National Laboratory, P.O. Box 5000, Upton, New York 11973 (United States); Conley, Ray [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Rennie, Kent; Kahn, Jim; Nethery, Richard [Kaufman & Robinson, Inc., 1330 Blue Spruce Drive, Fort Collins, Colorado 80524 (United States); Zhou, Lin [College of Mechatronics and Automation, National University of Defense Technology, 109 Deya Road, Changsha, Hunan 410073 (China); Hu’nan Key Laboratory of Ultra-precision Machining Technology, Changsha, Hunan 410073 (China)

    2015-10-15

    We report on the development of a one-dimensional Ion Beam Figuring (IBF) system for x-ray mirror polishing. Ion beam figuring provides a highly deterministic method for the final precision figuring of optical components with advantages over conventional methods. The system is based on a state of the art sputtering deposition system outfitted with a gridded radio frequency inductive coupled plasma ion beam source equipped with ion optics and dedicated slit developed specifically for this application. The production of an IBF system able to produce an elongated removal function rather than circular is presented in this paper, where we describe in detail the technical aspect and present the first obtained results.

  15. Supershort avalanche electron beams and x-ray in high-pressure nanosecond discharges

    International Nuclear Information System (INIS)

    Tarasenko, V F; Baksht, E H; Kostyrya, I D; Lomaev, M I; Rybka, D V

    2008-01-01

    The properties of a supershort avalanche electron beam (S AEB) and X-ray radiation produced using a nanosecond volume discharge are examined. An electron beam of the runaway electrons with amplitude of ∼ 50 A has been obtained in air atmospheric pressure. It is reported that S AEB is formed in the angle above 2π sr. Three groups of the runaway electrons are formed in a gas diode under atmospheric air pressure, when nanosecond voltage pulses with amplitude of hundreds of kilovolts are applied. The electron beam has been generated behind a 45 μm thick AlBe foil in SF 6 and Xe under the pressure of 2 arm, and in He under the pressure of about 12 atm. The paper gives the analysis of a generation mechanism of SAEB.

  16. Detection of x-rays emitted from a plasma focus device with energy of 2.8 KJ, and its applications in plasma diagnostic and radiography

    International Nuclear Information System (INIS)

    AL-Hawat, Sh.; Akel, M.

    2011-06-01

    The local plasma focus device was modified by replacing the old capacitors (25μF,20 kV ,1.43μH ) and the open spark gap by new capacitors with (25μF,20 kV ,200 nH ) and a new closed spark gap, so instead of a current of 50 kA as a maximum value we obtained a maximum current about 120 kA. The modified device is capable now to generate x-rays, which was confirmed by taking some radiographies for metallic pieces, electronic elements and others . In addition to that some diagnostics were carried out on the device using Ohm voltage divider to record voltage curves, Rogovskii coil for measuring the current, and five channel diodes to evaluate the temporal evolution of x-rays generated in the device working on argon vs. pressure and voltage. The generation of the soft x-ray emission in a low energy 2.8 kJ plasma focus device operated with argon using a detector of five PIN-Si BPX-65 diodes filtered with different foils of Mylar, Al and Cu. Spectral analysis using the recorded x-ray signals ratio method shows that there are two components in the x-ray emissions: one arising from the focused argon plasma with temperature of 2.5 keV and the other arising from the electron beam activity on copper anode, where the second component is predominant in most of investigated experiments due to the used of solid anode. Numerical experiments were carried out using five phases radiative Lee model RADPF5.15d-dd with N 2 , O 2 , Ar, Ne gases on plasma focus device AECS PF1-2 (or PF SY1-2) for its characterization and soft x-ray optimization. (author)

  17. Soft x-ray measurements in the FN-II dense plasma focus device for different anode configurations

    International Nuclear Information System (INIS)

    Rojo-Blanco, C; Castillo-Mejía, F; Rangel-Gutiérrez, J; Herrera-Velázquez, J J E

    2012-01-01

    A study of the soft x-ray emission is presented, for a low energy (4.8 kJ) dense plasma focus device. Three Quantrad Si PIN-diodes with differential filter combinations of Be, Al, Ti, Ni, and Mo are employed as time-resolved x-ray detectors. The x-ray flux in different energy windows is measured as function of the deuterium filling pressure. A comparison is made for three anode configurations: (a) hollow, (b) flat, and (c) 2mm diameter W needle.

  18. An empirical model of diagnostic x-ray attenuation under narrow-beam geometry

    International Nuclear Information System (INIS)

    Mathieu, Kelsey B.; Kappadath, S. Cheenu; White, R. Allen; Atkinson, E. Neely; Cody, Dianna D.

    2011-01-01

    Purpose: The purpose of this study was to develop and validate a mathematical model to describe narrow-beam attenuation of kilovoltage x-ray beams for the intended applications of half-value layer (HVL) and quarter-value layer (QVL) estimations, patient organ shielding, and computer modeling. Methods: An empirical model, which uses the Lambert W function and represents a generalized Lambert-Beer law, was developed. To validate this model, transmission of diagnostic energy x-ray beams was measured over a wide range of attenuator thicknesses [0.49-33.03 mm Al on a computed tomography (CT) scanner, 0.09-1.93 mm Al on two mammography systems, and 0.1-0.45 mm Cu and 0.49-14.87 mm Al using general radiography]. Exposure measurements were acquired under narrow-beam geometry using standard methods, including the appropriate ionization chamber, for each radiographic system. Nonlinear regression was used to find the best-fit curve of the proposed Lambert W model to each measured transmission versus attenuator thickness data set. In addition to validating the Lambert W model, we also assessed the performance of two-point Lambert W interpolation compared to traditional methods for estimating the HVL and QVL [i.e., semilogarithmic (exponential) and linear interpolation]. Results: The Lambert W model was validated for modeling attenuation versus attenuator thickness with respect to the data collected in this study (R 2 > 0.99). Furthermore, Lambert W interpolation was more accurate and less sensitive to the choice of interpolation points used to estimate the HVL and/or QVL than the traditional methods of semilogarithmic and linear interpolation. Conclusions: The proposed Lambert W model accurately describes attenuation of both monoenergetic radiation and (kilovoltage) polyenergetic beams (under narrow-beam geometry).

  19. An empirical model of diagnostic x-ray attenuation under narrow-beam geometry.

    Science.gov (United States)

    Mathieu, Kelsey B; Kappadath, S Cheenu; White, R Allen; Atkinson, E Neely; Cody, Dianna D

    2011-08-01

    The purpose of this study was to develop and validate a mathematical model to describe narrow-beam attenuation of kilovoltage x-ray beams for the intended applications of half-value layer (HVL) and quarter-value layer (QVL) estimations, patient organ shielding, and computer modeling. An empirical model, which uses the Lambert W function and represents a generalized Lambert-Beer law, was developed. To validate this model, transmission of diagnostic energy x-ray beams was measured over a wide range of attenuator thicknesses [0.49-33.03 mm Al on a computed tomography (CT) scanner, 0.09-1.93 mm Al on two mammography systems, and 0.1-0.45 mm Cu and 0.49-14.87 mm Al using general radiography]. Exposure measurements were acquired under narrow-beam geometry using standard methods, including the appropriate ionization chamber, for each radiographic system. Nonlinear regression was used to find the best-fit curve of the proposed Lambert W model to each measured transmission versus attenuator thickness data set. In addition to validating the Lambert W model, we also assessed the performance of two-point Lambert W interpolation compared to traditional methods for estimating the HVL and QVL [i.e., semi-logarithmic (exponential) and linear interpolation]. The Lambert W model was validated for modeling attenuation versus attenuator thickness with respect to the data collected in this study (R2 > 0.99). Furthermore, Lambert W interpolation was more accurate and less sensitive to the choice of interpolation points used to estimate the HVL and/or QVL than the traditional methods of semilogarithmic and linear interpolation. The proposed Lambert W model accurately describes attenuation of both monoenergetic radiation and (kilovoltage) polyenergetic beams (under narrow-beam geometry).

  20. High-field strong-focusing undulator designs for X-ray Linac Coherent Light Source (LCLS) applications

    International Nuclear Information System (INIS)

    Caspi, S.; Schlueter, R.; Tatchyn, R.

    1995-01-01

    Linac-driven X-Ray Free Electron Lasers (e.g., Linac Coherent Light Sources (LCLSs)), operating on the principle of single-pass saturation in the Self-Amplified Spontaneous Emission (SASE) regime typically require multi-GeV beam energies and undulator lengths in excess of tens of meters to attain sufficient gain in the 1 angstrom--0.1 angstrom range. In this parameter regime, the undulator structure must provide: (1) field amplitudes B 0 in excess of 1T within periods of 4cm or less, (2) peak on-axis focusing gradients on the order of 30T/m, and (3) field quality in the 0.1%--0.3% range. In this paper the authors report on designs under consideration for a 4.5--1.5 angstrom LCLS based on superconducting (SC), hybrid/PM, and pulsed-Cu technologies

  1. Investigation of plasma dynamics and x-ray emission in'ATON'plasma focus

    International Nuclear Information System (INIS)

    Soliman, H.M.; Masoud, M.M.

    1995-01-01

    The experimental studies on 20 kJ 'Aton' plasma focus device are presented in this paper. The plasma sheath structure has been investigated by means of the measurements of the axial and azimuthal magnetic fields along the coaxial electrodes. The operating gas was hydrogen with pressures in the range of 0.62 torr to 6 torr. The intensity of visible radiation emitted by the plasma sheath was measured as a function of axial distances along the coaxial electrodes. The results showed that the visible radiation intensity is increased with axial distances until a position near the muzzle, then it decreased and has a minimum value at the coaxial electrode muzzle. The main parameters contributing to the behavior of the distribution are the plasma sheath density and the impurities from the eroded materials of the discharge electrodes. An x-ray pulse has been detected along the coaxial electrodes and extended up to the expansion chamber. At a distance near the muzzle two x-ray pulses have been detected, the second one has intensity relative to the first one with time lag of 11μs. 8 fig

  2. Accelerator x-ray sources

    CERN Document Server

    Talman, Richard

    2007-01-01

    This first book to cover in-depth the generation of x-rays in particle accelerators focuses on electron beams produced by means of the novel Energy Recovery Linac (ERL) technology. The resulting highly brilliant x-rays are at the centre of this monograph, which continues where other books on the market stop. Written primarily for general, high energy and radiation physicists, the systematic treatment adopted by the work makes it equally suitable as an advanced textbook for young researchers.

  3. Nanometer Linear Focusing of Hard X Rays by a Multilayer Laue Lens

    International Nuclear Information System (INIS)

    Kang, H.C.; Stephenson, G.B.; Maser, J.; Liu, C.; Conley, R.; Macrander, A.T.; Vogt, S.

    2006-01-01

    We report on a type of linear zone plate for nanometer-scale focusing of hard x rays, a multilayer Laue lens (MLL), produced by sectioning a multilayer and illuminating it in Laue diffraction geometry. Because of its large optical depth, a MLL spans the diffraction regimes applicable to a thin Fresnel zone plate and a crystal. Coupled wave theory calculations indicate that focusing to 5 nm or smaller with high efficiency should be possible. Partial MLL structures with outermost zone widths as small as 10 nm have been fabricated and tested with 19.5 keV synchrotron radiation. Focal sizes as small as 30 nm with efficiencies up to 44% are measured

  4. Laser-powered dielectric-structures for the production of high-brightness electron and x-ray beams

    Science.gov (United States)

    Travish, Gil; Yoder, Rodney B.

    2011-05-01

    Laser powered accelerators have been under intensive study for the past decade due to their promise of high gradients and leveraging of rapid technological progress in photonics. Of the various acceleration schemes under examination, those based on dielectric structures may enable the production of relativistic electron beams in breadbox sized systems. When combined with undulators having optical-wavelength periods, these systems could produce high brilliance x-rays which find application in, for instance, medical and industrial imaging. These beams also may open the way for table-top atto-second sciences. Development and testing of these dielectric structures faces a number of challenges including complex beam dynamics, new demands on lasers and optical coupling, beam injection schemes, and fabrication. We describe one approach being pursued at UCLA-the Micro Accelerator Platform (MAP). A structure similar to the MAP has also been designed which produces periodic deflections and acts as an undulator for radiation production, and the prospects for this device will be considered. The lessons learned from the multi-year effort to realize these devices will be presented. Challenges remain with acceleration of sub-relativistic beams, focusing, beam phase stability and extension of these devices to higher beam energies. Our progress in addressing these hurdles will be summarized. Finally, the demands on laser technology and optical coupling will be detailed.

  5. Integral window/photon beam position monitor and beam flux detectors for x-ray beams

    Science.gov (United States)

    Shu, Deming; Kuzay, Tuncer M.

    1995-01-01

    A monitor/detector assembly in a synchrotron for either monitoring the position of a photon beam or detecting beam flux may additionally function as a vacuum barrier between the front end and downstream segment of the beamline in the synchrotron. A base flange of the monitor/detector assembly is formed of oxygen free copper with a central opening covered by a window foil that is fused thereon. The window foil is made of man-made materials, such as chemical vapor deposition diamond or cubic boron nitrate and in certain configurations includes a central opening through which the beams are transmitted. Sensors of low atomic number materials, such as aluminum or beryllium, are laid on the window foil. The configuration of the sensors on the window foil may be varied depending on the function to be performed. A contact plate of insulating material, such as aluminum oxide, is secured to the base flange and is thereby clamped against the sensor on the window foil. The sensor is coupled to external electronic signal processing devices via a gold or silver lead printed onto the contact plate and a copper post screw or alternatively via a copper screw and a copper spring that can be inserted through the contact plate and coupled to the sensors. In an alternate embodiment of the monitor/detector assembly, the sensors are sandwiched between the window foil of chemical vapor deposition diamond or cubic boron nitrate and a front foil made of similar material.

  6. Radiation dose response of N channel MOSFET submitted to filtered X-ray photon beam

    Science.gov (United States)

    Gonçalves Filho, Luiz C.; Monte, David S.; Barros, Fabio R.; Santos, Luiz A. P.

    2018-01-01

    MOSFET can operate as a radiation detector mainly in high-energy photon beams, which are normally used in cancer treatments. In general, such an electronic device can work as a dosimeter from threshold voltage shift measurements. The purpose of this article is to show a new way for measuring the dose-response of MOSFETs when they are under X-ray beams generated from 100kV potential range, which is normally used in diagnostic radiology. Basically, the method consists of measuring the MOSFET drain current as a function of the radiation dose. For this the type of device, it has to be biased with a high value resistor aiming to see a substantial change in the drain current after it has been irradiated with an amount of radiation dose. Two types of N channel device were used in the experiment: a signal transistor and a power transistor. The delivered dose to the device was varied and the electrical curves were plotted. Also, a sensitivity analysis of the power MOSFET response was made, by varying the tube potential of about 20%. The results show that both types of devices have responses very similar, the shift in the electrical curve is proportional to the radiation dose. Unlike the power MOSFET, the signal transistor does not provide a linear function between the dose rate and its drain current. We also have observed that the variation in the tube potential of the X-ray equipment produces a very similar dose-response.

  7. First steps of ion beam mixing: study by X-ray reflectometry and neutron diffraction

    International Nuclear Information System (INIS)

    Le Boite, M.G.

    1987-12-01

    There are several processes involved in ion beam mixing: ballistic processes, chemical driving forces and radiation enhanced diffusion. Experiments usually performed on bilayers irradiated with heavy elements and characterized by Rutherford backscattering (R.B.S.), have shown that the measured mixing rate is always higher than the calculated one, taking into account ballistic effects only. Besides classical R.B.S. experiments on NiAu and NiPt bilayers irradiated with Xe, we have used another technique of characterization: X-ray reflectometry and neutron diffraction, performed on multilayers irradiated with He. The systems are NiAu, NiPt, NiPd and NiAg, which behave similarly from the ballistic point of view, but have very different heats of mixing. In these experiments, the range of deposited energy density is very low, in contrast to heavy ions irradiation: this has allowed us to reach very low diffusion coefficient, never observed before. The dependence of the diffusion coefficient on the heat of mixing is in agreement with the one theoretically calculated. For the NiAg system, which has a positive heat of mixing, the measured diffusion coefficient is smaller than the ballistic one: a decrease of the ballistic mixing rate is seen for the first time. In this work, we have shown the interest of the reflectometry techniques (X-ray and neutrons); we have used a simple model to analyze the ion beam mixing, when elementary processes are involved

  8. Characterization of low energy X-rays beams with an extrapolation chamber

    International Nuclear Information System (INIS)

    Bastos, Fernanda Martins

    2015-01-01

    In laboratories involving Radiological Protection practices, it is usual to use reference radiations for calibrating dosimeters and to study their response in terms of energy dependence. The International Organization for Standardization (ISO) established four series of reference X-rays beams in the ISO- 4037 standard: the L and H series, as low and high air Kerma rates, respectively, the N series of narrow spectrum and W series of wide spectrum. The X-rays beams with tube potential below 30 kV, called 'low energy beams' are, in most cases, critical as far as the determination of their parameters for characterization purpose, such as half-value layer. Extrapolation chambers are parallel plate ionization chambers that have one mobile electrode that allows variation of the air volume in its interior. These detectors are commonly used to measure the quantity Absorbed Dose, mostly in the medium surface, based on the extrapolation of the linear ionization current as a function of the distance between the electrodes. In this work, a characterization of a model 23392 PTW extrapolation chamber was done in low energy X-rays beams of the ISO- 4037 standard, by determining the polarization voltage range through the saturation curves and the value of the true null electrode spacing. In addition, the metrological reliability of the extrapolation chamber was studied with measurements of the value of leakage current and repeatability tests; limit values were established for the proper use of the chamber. The PTW23392 extrapolation chamber was calibrated in terms of air Kerma in some of the ISO radiation series of low energy; the traceability of the chamber to the National Standard Dosimeter was established. The study of energy dependency of the extrapolation chamber and the assessment of the uncertainties related to the calibration coefficient were also done; it was shown that the energy dependence was reduced to 4% when the extrapolation technique was used. Finally, the first

  9. Numerical experiments on plasma focus for soft x-ray yield scaling laws derivation using Lee model

    International Nuclear Information System (INIS)

    Akel, M.

    2015-01-01

    The required plasma parameters of krypton and xenon at different temperatures were calculated, the x-ray emission properties of plasmas were studied, and based on the corona model the suitable temperature range for generating H-like and He-like ions (therefore soft x-ray emissions) of different gases plasma were found. The code is applied to characterize the plasma focus in different plasma focus devices, and for optimizing the nitrogen, oxygen, neon, argon, krypton and xenon soft x-ray yields based on bank, tubes and operating parameters. It is found that t he soft x-ray yield increases with changing pressure until it reaches the maximum value for each plasma focus device. Keeping the bank parameters, operational voltage unchanged but systematically changing other parameters, numerical experiments were performed finding the optimum combination of Po, z0 and 'a' for the maximum soft x-ray yield. Thus we expect to increase the soft x-ray yield of plasma focus device several-fold from its present typical operation; without changing the capacitor bank, merely by changing the electrode configuration and the operating pressure. The Lee model code was also used to run numerical experiments on plasma focus devices for optimizing soft x-ray yield with reducing Lo, varying z0 and 'a' to get engineering designs with maximum soft x-ray yield for these devices at different experimental conditions and gases. Numerical experiments showed the influence of the gas used in plasma focus and its propor ties on soft x-ray emission and its propor ties and then on its applications. Scaling laws for soft x-ray of nitrogen, oxygen, neon, argon, krypton and xenon plasma focus in terms of energy, peak discharge current and focus pinch current were found. Radiative cooling effects are studied indicating that radiative collapse may be observed for heavy noble gases (Ar, Kr, Xe) for pinch currents even below 100 k A. The results show that the line radiation emission and

  10. Numerical experiments on plasma focus for soft x-ray yield scaling laws derivation using Lee model

    International Nuclear Information System (INIS)

    Akel, M.

    2012-09-01

    The required plasma parameters of krypton and xenon at different temperatures were calculated, the x-ray emission properties of plasmas were studied, and based on the corona model the suitable temperature range for generating H-like and He-like ions (therefore soft x-ray emissions) of different gases plasma were found. The code is applied to characterize the plasma focus in different plasma focus devices, and for optimizing the nitrogen, oxygen, neon, argon, krypton and xenon soft x-ray yields based on bank, tubes and operating parameters. It is found that the soft x-ray yield increases with changing pressure until it reaches the maximum value for each plasma focus device. Keeping the bank parameters, operational voltage unchanged but systematically changing other parameters, numerical experiments were performed finding the optimum combination of P o , Z o and 'a' for the maximum soft x-ray yield. Thus we expect to increase the soft x-ray yield of plasma focus device several-fold from its present typical operation; without changing the capacitor bank, merely by changing the electrode configuration and the operating pressure. The Lee model code was also used to run numerical experiments on plasma focus devices for optimizing soft x-ray yield with reducing L o , varying L o and 'a' to get engineering designs with maximum soft x-ray yield for these devices at different experimental conditions and gases. Numerical experiments showed the influence of the gas used in plasma focus and its properties on soft x-ray emission and its properties and then on its applications. Scaling laws for soft x-ray of nitrogen, oxygen, neon, argon, krypton and xenon plasma focus, in terms of energy, peak discharge current and focus pinch current were found. Radiative cooling effects are studied indicating that radiative collapse may be observed for heavy noble gases (Ar, Kr, Xe) for pinch currents even below 100 kA. The results show that the line radiation emission and tube voltages have

  11. Heat load studies of a water-cooled minichannel monochromator for synchrotron x-ray beams

    Science.gov (United States)

    Freund, Andreas K.; Arthur, John R.; Zhang, Lin

    1997-12-01

    We fabricated a water-cooled silicon monochromator crystal with small channels for the special case of a double-crystal fixed-exit monochromator design where the beam walks across the crystal when the x-ray energy is changed. The two parts of the cooled device were assembled using a new technique based on low melting point solder. The bending of the system produced by this technique could be perfectly compensated by mechanical counter-bending. Heat load tests of the monochromator in a synchrotron beam of 75 W total power, 3 mm high and 15 mm wide, generated by a multipole wiggler at SSRL, showed that the thermal slope error of the crystal is 1 arcsec/40 W power, in full agreement with finite element analysis. The cooling scheme is adequate for bending magnet beamlines at the ESRF and present wiggler beamlines at the SSRL.

  12. X-ray streak camera for observation of tightly pinched relativistic electron beams

    International Nuclear Information System (INIS)

    Johnson, D.J.

    1977-01-01

    A pinhole camera is coupled with a Pilot-B scintillator and image-intensified TRW streak camera to study pinched electron beam profiles via observation of anode target bremsstrahlung. Streak intensification is achieved with an EMI image intensifier operated at a gain of up to 10 6 which allows optimizing the pinhole configuration so that resolution is simultaneously limited by photon-counting statistics and pinhole geometry. The pinhole used is one-dimensional and is fabricated by inserting uranium shims with hyperbolic curved edges between two 5-cm-thick lead blocks. The loss of spatial resolution due to the x-ray transmission through the perimeter of the pinhole is calculated and a streak photograph of a Gamble I pinched beam interacting with a brass anode is presented

  13. Simulating systematic errors in X-ray absorption spectroscopy experiments: Sample and beam effects

    Energy Technology Data Exchange (ETDEWEB)

    Curis, Emmanuel [Laboratoire de Biomathematiques, Faculte de Pharmacie, Universite Rene, Descartes (Paris V)-4, Avenue de l' Observatoire, 75006 Paris (France)]. E-mail: emmanuel.curis@univ-paris5.fr; Osan, Janos [KFKI Atomic Energy Research Institute (AEKI)-P.O. Box 49, H-1525 Budapest (Hungary); Falkenberg, Gerald [Hamburger Synchrotronstrahlungslabor (HASYLAB), Deutsches Elektronen-Synchrotron (DESY)-Notkestrasse 85, 22607 Hamburg (Germany); Benazeth, Simone [Laboratoire de Biomathematiques, Faculte de Pharmacie, Universite Rene, Descartes (Paris V)-4, Avenue de l' Observatoire, 75006 Paris (France); Laboratoire d' Utilisation du Rayonnement Electromagnetique (LURE)-Ba-hat timent 209D, Campus d' Orsay, 91406 Orsay (France); Toeroek, Szabina [KFKI Atomic Energy Research Institute (AEKI)-P.O. Box 49, H-1525 Budapest (Hungary)

    2005-07-15

    The article presents an analytical model to simulate experimental imperfections in the realization of an X-ray absorption spectroscopy experiment, performed in transmission or fluorescence mode. Distinction is made between sources of systematic errors on a time-scale basis, to select the more appropriate model for their handling. For short time-scale, statistical models are the most suited. For large time-scale, the model is developed for sample and beam imperfections: mainly sample inhomogeneity, sample self-absorption, beam achromaticity. The ability of this model to reproduce the effects of these imperfections is exemplified, and the model is validated on real samples. Various potential application fields of the model are then presented.

  14. Simulating systematic errors in X-ray absorption spectroscopy experiments: Sample and beam effects

    International Nuclear Information System (INIS)

    Curis, Emmanuel; Osan, Janos; Falkenberg, Gerald; Benazeth, Simone; Toeroek, Szabina

    2005-01-01

    The article presents an analytical model to simulate experimental imperfections in the realization of an X-ray absorption spectroscopy experiment, performed in transmission or fluorescence mode. Distinction is made between sources of systematic errors on a time-scale basis, to select the more appropriate model for their handling. For short time-scale, statistical models are the most suited. For large time-scale, the model is developed for sample and beam imperfections: mainly sample inhomogeneity, sample self-absorption, beam achromaticity. The ability of this model to reproduce the effects of these imperfections is exemplified, and the model is validated on real samples. Various potential application fields of the model are then presented

  15. Automatic local beam steering systems for NSLS x-ray storage ring: Design and implementation

    International Nuclear Information System (INIS)

    Singh, O.V.; Nawrocky, R.; Flannigan, J.

    1991-01-01

    Recently, two local automatic steering systems, controlled by microprocessors, have been installed and commissioned in the NSLS X- Ray storage ring. In each system, the position of the electron beam is stabilized at two locations by four independent servo systems. This paper describes three aspects of the local feedback program: design; commissioning; and limitation. The system design is explained by identifying major elements such as beam position detectors, signal processors, compensation amplifiers, ratio amplifiers, trim equalizers and microprocessor feedback controllers. System commissioning involves steps such as matching trim compensation, determination of local orbit bumps, measurement of open loop responses and design of servo circuits. Several limitations of performance are also discussed. 7 refs., 2 figs

  16. Output Beam Polarisation of X-ray Lasers with Transient Inversion

    Science.gov (United States)

    Janulewicz, K. A.; Kim, C. M.; Matouš, B.; Stiel, H.; Nishikino, M.; Hasegawa, N.; Kawachi, T.

    It is commonly accepted that X-ray lasers, as the devices based on amplified spontaneous emission (ASE), did not show any specific polarization in the output beam. The theoretical analysis within the uniform (single-mode) approximation suggested that the output radiation should show some defined polarization feature, but randomly changing from shot-to-shot. This hypothesis has been verified by experiment using traditional double-pulse scheme of transient inversion. Membrane beam-splitter was used as a polarization selector. It was found that the output radiation has a significant component of p-polarisation in each shot. To explain the effect and place it in the line with available, but scarce data, propagation and kinetic effects in the non-uniform plasma have been analysed.

  17. Measurement of conversion coefficients between air Kerma and personal dose equivalent and backscatter factors for diagnostic X-ray beams

    International Nuclear Information System (INIS)

    Rosado, Paulo Henrique Goncalves

    2008-01-01

    Two sets of quantities are import in radiological protection: the protection and operational quantities. Both sets can be related to basic physical quantities such as kerma through conversion coefficients. For diagnostic x-ray beams the conversion coefficients and backscatter factors have not been determined yet, those parameters are need for calibrating dosimeters that will be used to determine the personal dose equivalent or the entrance skin dose. Conversion coefficients between air kerma and personal dose equivalent and backscatter factors were experimentally determined for the diagnostic x-ray qualities RQR and RQA recommended by the International Electrotechnical Commission (IEC). The air kerma in the phantom and the mean energy of the spectrum were measured for such purpose. Harshaw LiF-100H thermoluminescent dosemeters (TLD) were used for measurements after being calibrated against an 180 cm 3 Radcal Corporation ionization chamber traceable to a reference laboratory. A 300 mm x 300 mm x 150 mm polymethylmethacrylate (PMMA) slab phantom was used for deep-dose measurements. Tl dosemeters were placed in the central axis of the x-ray beam at 5, 10, 15, 25 and 35 mm depth in the phantom upstream the beam direction Another required parameter for determining the conversion coefficients from was the mean energy of the x-ray spectrum. The spectroscopy of x-ray beams was done with a CdTe semiconductor detector that was calibrated with 133 Ba, 241 Am and 57 Co radiation sources. Measurements of the x-ray spectra were carried out for all RQR and RQA IEC qualities. Corrections due to the detector intrinsic efficiency, total energy absorption, escape fraction of the characteristic x-rays, Compton effect and attenuation in the detector were done aiming an the accurate determination of the mean energy. Measured x-ray spectra were corrected with the stripping method by using these response functions. The typical combined standard uncertainties of conversion coefficients and

  18. Studies of the Hard X-ray Emission from the Filippov Type Plasma Focus Device, Dena

    Science.gov (United States)

    Tafreshi, M. A.; Saeedzadeh, E.

    2006-12-01

    This article is about the characteristics of the hard X-ray (HXR) emission from the Filippov type plasma focus (PF) device, Dena. The article begins with a brief presentation of Dena, and the mechanism of the HXR production in PF devices. Then using the differential absorption spectrometry, the energy resolved spectrum of the HXR emission from a 37 kJ discharge in Dena, is estimated. The energy flux density and the energy fluence of this emission have also been calculated to be 1.9 kJ cm-2 s-1 and 9.4 × 10-5 J cm-2. In the end, after presentation of radiography of sheep bones and calf ribs, the medical application of the PF devices has been discussed.

  19. The First Focused Hard X-Ray Images of the Sun With NuSTAR

    DEFF Research Database (Denmark)

    Grefenstette, Brian W.; Glesener, Lindsay; Krucker, Sam

    2016-01-01

    We present results from the the first campaign of dedicated solar observations undertaken by the Nuclear Spectroscopic Telescope ARray (NuSTAR) hard X-ray (HXR) telescope. Designed as an astrophysics mission, NuSTAR nonetheless has the capability of directly imaging the Sun at HXR energies (>3 ke......V) with an increase in sensitivity of at least two magnitude compared to current non-focusing telescopes. In this paper we describe the scientific areas where NuSTAR will make major improvements on existing solar measurements. We report on the techniques used to observe the Sun with NuSTAR, their limitations......, and full-disk HXR images of the Sun....

  20. Micro-focus x-ray inspection of the bearing pad welded by laser for CANDU fuel element

    International Nuclear Information System (INIS)

    Kim, W. K.; Kim, S. S.; Lee, J. W.; Yang, M. S.

    2001-01-01

    To attach the bearing pads on the surface of CANDU fuel element, laser welding technique has been reviewed to replace brazing technology which is complicate process and makes use of the toxic beryllium. In this study, to evaluate the soundness of the weld of the bearing pad of CANDU fuel element, a precise X-ray inspection system was developed using a micro-focus X-ray generator with an image intensifier and a real time camera system. The weld of the bearing pad welded by Nd:YAG laser has been inspected by the developed inspection system. Image processing technique has been applied to reduce random noise and to enhance the contrast of the X-ray image. A few defects on the weld of the bearing pads have been detected by the X-ray inspection process

  1. Skin dose from radiotherapy X-ray beams: the influence of energy

    International Nuclear Information System (INIS)

    Butson, M.J.; Metcalfe, P.E.; University of Wollongong, Wollongong, NSW; Mathur, J.N.

    1997-01-01

    Skin-sparing properties of megavoltage photon beams are compromised by electron contamination. Higher energy beams do not necessarily produce lower surface and basal cell layer doses due to this electron contamination. For a 5x5 cm field size the surface doses for 6 MVp and 18 M)p X-ray beams are 10% and 7% of their respective maxima. However, at a field size of 40 x 40cm the percentage surface dose is 42% for both 6 MVp and 18 MVp beams. The introduction of beam modifying devices such as block trays can further reduce the skin-sparing advantages of high energy photon beams. Using a 10 mm perspex block tray, the surface doses for 6 MVp and 18 MVp beams with a 5 x 5 cm field size are 10% and 8%, respectively. At 40 x 40cm, surface doses are 61% and 63% for 6 MVp and 18 MVp beams, respectively. This trend is followed at the basal cell layer depth. At a depth of 1 mm, 18 MVp beam doses are always at least 5% smaller than 6 MVp doses for the same depth at all field sizes when normalized to their respective Dmax values. Results have shown that higher energy photon beams produce a negligible reduction of the delivered dose to the basal cell layer (0.1 mm). Only a small increase in skin sparing is seen at the dermal layer (1 mm), which can be negated by the increased exit dose from an opposing field. (authors)

  2. Development of a Hard X-ray Beam Position Monitor for Insertion Device Beams at the APS

    Science.gov (United States)

    Decker, Glenn; Rosenbaum, Gerd; Singh, Om

    2006-11-01

    Long-term pointing stability requirements at the Advanced Photon Source (APS) are very stringent, at the level of 500 nanoradians peak-to-peak or better over a one-week time frame. Conventional rf beam position monitors (BPMs) close to the insertion device source points are incapable of assuring this level of stability, owing to mechanical, thermal, and electronic stability limitations. Insertion device gap-dependent systematic errors associated with the present ultraviolet photon beam position monitors similarly limit their ability to control long-term pointing stability. We report on the development of a new BPM design sensitive only to hard x-rays. Early experimental results will be presented.

  3. A portable Compton spectrometer for clinical X-ray beams in the energy range 20-150 keV

    International Nuclear Information System (INIS)

    Vieira, A.A.; Linke, A.; Yoshimura, E.M.; Terini, R.A.; Herdade, S.B.

    2011-01-01

    Primary beam spectra were obtained for an X-ray industrial equipment (40-150 kV), and for a clinical mammography apparatus (25-35 kV) from beams scattered at angles close to 90 o , measured with a CdTe Compton spectrometer. Actual scattering angles were determined from the Compton energy shift of characteristic X-rays or spectra end-point energy. Evaluated contribution of coherent scattering amounts to more than 15% of fluence in mammographic beams. This technique can be used in clinical environments.

  4. Absolute x-ray dosimetry on a synchrotron medical beam line with a graphite calorimeter.

    Science.gov (United States)

    Harty, P D; Lye, J E; Ramanathan, G; Butler, D J; Hall, C J; Stevenson, A W; Johnston, P N

    2014-05-01

    The absolute dose rate of the Imaging and Medical Beamline (IMBL) on the Australian Synchrotron was measured with a graphite calorimeter. The calorimetry results were compared to measurements from the existing free-air chamber, to provide a robust determination of the absolute dose in the synchrotron beam and provide confidence in the first implementation of a graphite calorimeter on a synchrotron medical beam line. The graphite calorimeter has a core which rises in temperature when irradiated by the beam. A collimated x-ray beam from the synchrotron with well-defined edges was used to partially irradiate the core. Two filtration sets were used, one corresponding to an average beam energy of about 80 keV, with dose rate about 50 Gy/s, and the second filtration set corresponding to average beam energy of 90 keV, with dose rate about 20 Gy/s. The temperature rise from this beam was measured by a calibrated thermistor embedded in the core which was then converted to absorbed dose to graphite by multiplying the rise in temperature by the specific heat capacity for graphite and the ratio of cross-sectional areas of the core and beam. Conversion of the measured absorbed dose to graphite to absorbed dose to water was achieved using Monte Carlo calculations with the EGSnrc code. The air kerma measurements from the free-air chamber were converted to absorbed dose to water using the AAPM TG-61 protocol. Absolute measurements of the IMBL dose rate were made using the graphite calorimeter and compared to measurements with the free-air chamber. The measurements were at three different depths in graphite and two different filtrations. The calorimetry measurements at depths in graphite show agreement within 1% with free-air chamber measurements, when converted to absorbed dose to water. The calorimetry at the surface and free-air chamber results show agreement of order 3% when converted to absorbed dose to water. The combined standard uncertainty is 3.9%. The good agreement of

  5. Blade-type X-ray beam position monitors for SPring-8 undulator beamlines

    CERN Document Server

    Aoyagi, H; Kitamura, H

    2001-01-01

    The X-ray beam position monitors had been designed and installed for SPring-8 insertion device beamlines. These monitors are being utilized for photon beam diagnostics. The beam from the standard undulator in SPring-8 has the total power of 11 kW and the power density of 470 kW/mrad sup 2 , typically. Each monitor has four CVD diamond blades coated with metal for detector heads. We have already introduced three styles of monitors to match various insertion devices in SPring-8. A standard style, or a fixed-blade style, is used mainly for a standard in-vacuum undulator beamlines. A horizontal-blade-drive style and a four-blade-drive style are used for beamlines of a wiggler and a twin helical undulator that have wide power distributions, and for figure-8 undulators that have asymmetric power distributions, respectively. This report describes the design and the structure of these monitors and the beam-tests for the photon beam diagnostics in detail.

  6. Automated marker tracking using noisy X-ray images degraded by the treatment beam

    International Nuclear Information System (INIS)

    Wisotzky, E.; Fast, M.F.; Nill, S.

    2015-01-01

    This study demonstrates the feasibility of automated marker tracking for the real-time detection of intrafractional target motion using noisy kilovoltage (kV) X-ray images degraded by the megavoltage (MV) treatment beam. The authors previously introduced the in-line imaging geometry, in which the flat-panel detector (FPD) is mounted directly underneath the treatment head of the linear accelerator. They found that the 121 kVp image quality was severely compromised by the 6 MV beam passing through the FPD at the same time. Specific MV-induced artefacts present a considerable challenge for automated marker detection algorithms. For this study, the authors developed a new imaging geometry by re-positioning the FPD and the X-ray tube. This improved the contrast-to-noise-ratio between 40% and 72% at the 1.2 mAs/image exposure setting. The increase in image quality clearly facilitates the quick and stable detection of motion with the aid of a template matching algorithm. The setup was tested with an anthropomorphic lung phantom (including an artificial lung tumour). In the tumour one or three Calypso registered beacons were embedded to achieve better contrast during MV radiation. For a single beacon, image acquisition and automated marker detection typically took around 76±6 ms. The success rate was found to be highly dependent on imaging dose and gantry angle. To eliminate possible false detections, the authors implemented a training phase prior to treatment beam irradiation and also introduced speed limits for motion between subsequent images.

  7. Automated marker tracking using noisy X-ray images degraded by the treatment beam

    Energy Technology Data Exchange (ETDEWEB)

    Wisotzky, E. [Fraunhofer Institute for Production Systems and Design Technology (IPK), Berlin (Germany); German Cancer Research Center (DKFZ), Heidelberg (Germany); Fast, M.F.; Nill, S. [The Royal Marsden NHS Foundation Trust, London (United Kingdom). Joint Dept. of Physics; Oelfke, U. [The Royal Marsden NHS Foundation Trust, London (United Kingdom). Joint Dept. of Physics; German Cancer Research Center (DKFZ), Heidelberg (Germany)

    2015-09-01

    This study demonstrates the feasibility of automated marker tracking for the real-time detection of intrafractional target motion using noisy kilovoltage (kV) X-ray images degraded by the megavoltage (MV) treatment beam. The authors previously introduced the in-line imaging geometry, in which the flat-panel detector (FPD) is mounted directly underneath the treatment head of the linear accelerator. They found that the 121 kVp image quality was severely compromised by the 6 MV beam passing through the FPD at the same time. Specific MV-induced artefacts present a considerable challenge for automated marker detection algorithms. For this study, the authors developed a new imaging geometry by re-positioning the FPD and the X-ray tube. This improved the contrast-to-noise-ratio between 40% and 72% at the 1.2 mAs/image exposure setting. The increase in image quality clearly facilitates the quick and stable detection of motion with the aid of a template matching algorithm. The setup was tested with an anthropomorphic lung phantom (including an artificial lung tumour). In the tumour one or three Calypso {sup registered} beacons were embedded to achieve better contrast during MV radiation. For a single beacon, image acquisition and automated marker detection typically took around 76±6 ms. The success rate was found to be highly dependent on imaging dose and gantry angle. To eliminate possible false detections, the authors implemented a training phase prior to treatment beam irradiation and also introduced speed limits for motion between subsequent images.

  8. Commercial CMOS image sensors as X-ray imagers and particle beam monitors

    International Nuclear Information System (INIS)

    Castoldi, A.; Guazzoni, C.; Maffessanti, S.; Montemurro, G.V.; Carraresi, L.

    2015-01-01

    CMOS image sensors are widely used in several applications such as mobile handsets webcams and digital cameras among others. Furthermore they are available across a wide range of resolutions with excellent spectral and chromatic responses. In order to fulfill the need of cheap systems as beam monitors and high resolution image sensors for scientific applications we exploited the possibility of using commercial CMOS image sensors as X-rays and proton detectors. Two different sensors have been mounted and tested. An Aptina MT9v034, featuring 752 × 480 pixels, 6μm × 6μm pixel size has been mounted and successfully tested as bi-dimensional beam profile monitor, able to take pictures of the incoming proton bunches at the DeFEL beamline (1–6 MeV pulsed proton beam) of the LaBeC of INFN in Florence. The naked sensor is able to successfully detect the interactions of the single protons. The sensor point-spread-function (PSF) has been qualified with 1MeV protons and is equal to one pixel (6 mm) r.m.s. in both directions. A second sensor MT9M032, featuring 1472 × 1096 pixels, 2.2 × 2.2 μm pixel size has been mounted on a dedicated board as high-resolution imager to be used in X-ray imaging experiments with table-top generators. In order to ease and simplify the data transfer and the image acquisition the system is controlled by a dedicated micro-processor board (DM3730 1GHz SoC ARM Cortex-A8) on which a modified LINUX kernel has been implemented. The paper presents the architecture of the sensor systems and the results of the experimental measurements

  9. Building a Graphite Calorimetry System for the Dosimetry of Therapeutic X-ray Beams

    Directory of Open Access Journals (Sweden)

    In Jung Kim

    2017-06-01

    Full Text Available A graphite calorimetry system was built and tested under irradiation. The noise level of the temperature measurement system was approximately 0.08 mK (peak to peak. The temperature of the core part rose by approximately 8.6 mK at 800 MU (monitor unit for 6-MV X-ray beams, and it increased as X-ray energy increased. The temperature rise showed less spread when it was normalized to the accumulated charge, as measured by an external monitoring chamber. The radiation energy absorbed by the core part was determined to have values of 0.798 J/μC, 0.389 J/μC, and 0.352 J/μC at 6 MV, 10 MV, and 18 MV, respectively. These values were so consistent among repeated runs that their coefficient of variance was less than 0.15%.

  10. Wolter type I x-ray focusing mirror using multilayer coatings

    International Nuclear Information System (INIS)

    Chon, Kwon Su; Namba, Yoshiharu; Yoon, Kwon-Ha

    2006-01-01

    A multilayer coating is a useful addition to a mirror in the x-ray region and has been applied to normal incidence mirrors used with soft x rays. When a multilayer coating is used on grazing incidence optics, higher performance can be achieved than without it.Cr/Sc multilayers coated on a Wolter type I mirror substrate for a soft x-ray microscope are considered. The reflectivity and effective solid angle are calculated for Wolter type I mirrors with uniform and laterally graded multilayer coatings. The laterally graded multilayer mirror showed superior x-ray performance, and the multilayer tolerances were relaxed. This multilayer mirror could be especially useful in the soft x-ray microscope intended for biological applications

  11. Advanced simulations of x-ray beam propagation through CRL transfocators using ray-tracing and wavefront propagation methods

    DEFF Research Database (Denmark)

    Baltser, Jana; Bergbäck Knudsen, Erik; Vickery, Anette

    2011-01-01

    Compound refractive lenses (CRL) are widely used to manipulate synchrotron radiation beams. Accurate modelling of X-ray beam propagation through individual lenses and through "transfocators" composed of a large number of CRLs is of high importance, since it allows for comprehensive optimization...

  12. Manufacturing method for hard x-ray focusing mirrors with ellipsoidal surface

    International Nuclear Information System (INIS)

    Yumoto, Hirokatsu; Koyama, Takahisa; Ohashi, Haruhiko; Matsuyama, Satoshi; Yamauchi, Kazuto

    2014-01-01

    The aim of this study is to establishing the manufacturing method for hard x-ray nano-focusing mirrors with ellipsoidal surface. Ellipsoidal mirror optics, which can produce point focus with a mirror, has a noticeable feature of a high focusing efficiency, although an ultra-precise surface figure with an accuracy of a few nanometers is required for nano-focusing mirrors. Here, we examined the effectiveness of the manufacturing process for ellipsoidal mirrors, which is consisted of a precision grinding process, a removal process of surface roughness, and a computer-controlled shape correction. The precision processing machine for both a removal of surface roughness and a shape correction was developed. This validated the utility of removing surface roughness with a spatial wavelength of 40 μm, which is the tool mark of the grinding process. The developed process achieved the improvement of surface roughness from 1.6 nm to 0.1 nm (RMS), and the figure correction with a high accuracy of < 10 nm and a spatial resolution of < 2 mm. (author)

  13. Influence of the crystal-surface unevenness on the angular spread of an x-ray diffracted beam

    International Nuclear Information System (INIS)

    Hrda, JaromIra; Potlovskiy, Kirill; Hrdy, JaromIr; Slechtova, Venceslava

    2005-01-01

    One of the factors influencing the focus size in diffractive-refractive optics is the quality of diffracting surface. If the surface is uneven, as it is when the silicon crystal surface is only etched, then the diffraction at each point of the surface is a combination of an asymmetric and inclined diffraction (general asymmetric diffraction). This somewhat deviates and spreads the diffracted beam. The integration over the surface hit by an incident beam gives the angular spread of the diffracted beam. It is shown theoretically that in some cases (highly asymmetric, highly inclined cut) the etched surface may create the spread of the diffracted beam such that it causes a significant broadening of the focus. In this case a mechanical-chemical polishing is necessary. This has been verified by us earlier in a preliminary experiment with synchrotron radiation. In this work the new experiment with the same crystals is performed using double crystal (+, -) arrangement and a laboratory x-ray source (CuKα radiation). We compared two samples; one of them is mechanically-chemically (MC) polished and thus the diffracting surface is almost perfect; the other is only etched. This experiment allows a better comparison of the result with the theory. The difference between the measured rocking curve widths for the etched and MC polished crystals (10'') roughly agrees with theory (7''), which supports the correctness of the theoretical approach

  14. Scaling Laws of Nitrogen Soft X-Ray Yields from 1 to 200 kJ Plasma Focus

    International Nuclear Information System (INIS)

    Akel, M.; Lee, S.

    2013-01-01

    Numerical experiments are carried out systematically to determine the nitrogen soft x-ray yield for optimized nitrogen plasma focus with storage energy E 0 from 1 kJ to 200 kJ. Scaling laws on nitrogen soft x-ray yield, in terms of storage energies E 0 , peak discharge current I p eak and focus pinch current I p inch were found. It was found that the nitrogen x-ray yields scales on average with y s xr, N= 1.93xE o 1 .21 J (E 0 in kJ) with the scaling showing gradual deterioration as E 0 rises over the range. A more robust scaling is y s xr = 8x10 - 8I 0 3.38 p inch . The optimum nitrogen soft x-ray yield emitted from plasma focus is found to be about 1 kJ for storage energy of 200 kJ. This indicates that nitrogen plasma focus is a good water-window soft x-ray source when properly designed. (author)

  15. A comparison of chemical and ionization dosimetry for high-energy x-ray and electron beams

    International Nuclear Information System (INIS)

    Durocher, J.J.; Boese, H.; Cormack, D.V.; Holloway, A.F.

    1981-01-01

    A comparison was made of ferrous sulfate (Fricke) and ionometric methods for determining the absorbed dose in a phantom irradiated with 4-MV x-rays, 25-MV x-rays, or electron beams having various incident energies between 10 and 32 MeV. Both chemical and ionization instruments were calibrated in a 60 Co beam at a point in water where the absorbed dose had been previously determined. The chemical yield measurements were corrected for spatial variations in dose within the volume of the solution and used to obtain a value of the absorbed dose for each of the x-ray and electron beams. The ratios of G-values required for these determinations were taken from ICRU reports 14 and 21. Ionization instrument readings from three types of commercial ionization chambers were used to obtain alternate values of the absorbed dose for each radiation. C lambda and CE values used in determining these ionization values of dose were also taken from the above ICRU reports. For 4-MV x-rays the values of absorbed dose obtained from chemical measurements agreed to within 0.5% with values obtained from ionization measurements; for 25-MV x-rays the chemical values were about 1% higher than the ionization values; for the electron beams the chemical values were 1%-4% below the ionization values. These discrepancies suggest an inconsistency among the recommended G, C lambda, and CE values similar to that which has been noted by other workers

  16. Simulations of x-ray speckle-based dark-field and phase-contrast imaging with a polychromatic beam

    Energy Technology Data Exchange (ETDEWEB)

    Zdora, Marie-Christine, E-mail: marie-christine.zdora@diamond.ac.uk [Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, 85748 Garching (Germany); Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE (United Kingdom); Department of Physics & Astronomy, University College London, London WC1E 6BT (United Kingdom); Thibault, Pierre [Department of Physics & Astronomy, University College London, London WC1E 6BT (United Kingdom); Pfeiffer, Franz [Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, 85748 Garching (Germany); Zanette, Irene [Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, 85748 Garching (Germany); Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE (United Kingdom)

    2015-09-21

    Following the first experimental demonstration of x-ray speckle-based multimodal imaging using a polychromatic beam [I. Zanette et al., Phys. Rev. Lett. 112(25), 253903 (2014)], we present a simulation study on the effects of a polychromatic x-ray spectrum on the performance of this technique. We observe that the contrast of the near-field speckles is only mildly influenced by the bandwidth of the energy spectrum. Moreover, using a homogeneous object with simple geometry, we characterize the beam hardening artifacts in the reconstructed transmission and refraction angle images, and we describe how the beam hardening also affects the dark-field signal provided by speckle tracking. This study is particularly important for further implementations and developments of coherent speckle-based techniques at laboratory x-ray sources.

  17. X-ray beam hardening correction for measuring density in linear accelerator industrial computed tomography

    International Nuclear Information System (INIS)

    Zhou Rifeng; Wang Jue; Chen Weimin

    2009-01-01

    Due to X-ray attenuation being approximately proportional to material density, it is possible to measure the inner density through Industrial Computed Tomography (ICT) images accurately. In practice, however, a number of factors including the non-linear effects of beam hardening and diffuse scattered radiation complicate the quantitative measurement of density variations in materials. This paper is based on the linearization method of beam hardening correction, and uses polynomial fitting coefficient which is obtained by the curvature of iron polychromatic beam data to fit other materials. Through theoretical deduction, the paper proves that the density measure error is less than 2% if using pre-filters to make the spectrum of linear accelerator range mainly 0.3 MeV to 3 MeV. Experiment had been set up at an ICT system with a 9 MeV electron linear accelerator. The result is satisfactory. This technique makes the beam hardening correction easy and simple, and it is valuable for measuring the ICT density and making use of the CT images to recognize materials. (authors)

  18. X-ray Tomography Characterisation of Lattice Structures Processed by Selective Electron Beam Melting

    Directory of Open Access Journals (Sweden)

    Everth Hernández-Nava

    2017-08-01

    Full Text Available Metallic lattice structures intentionally contain open porosity; however, they can also contain unwanted closed porosity within the structural members. The entrained porosity and defects within three different geometries of Ti-6Al-4V lattices, fabricated by Selective Electron Beam Melting (SEBM, is assessed from X-ray computed tomography (CT scans. The results suggest that horizontal struts that are built upon loose powder show particularly high (~20 × 10−3 vol % levels of pores, as do nodes at which many (in our case 24 struts meet. On the other hand, for struts more closely aligned (0° to 54° to the build direction, the fraction of porosity appears to be much lower (~0.17 × 10−3% arising mainly from pores contained within the original atomised powder particles.

  19. Evaluation of a tissue equivalent ionization chamber in X-ray beams

    Energy Technology Data Exchange (ETDEWEB)

    Perini, Ana Paula; Neves, Lucio Pereira; Santos, William de Souza; Caldas, Linda V.E., E-mail: aperini@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Frimaio, Audrew [Seal Technology Ind. Com. Ltda, Sao Paulo, SP (Brazil); Costa, Paulo R. [Universidade de Sao Paulo (USP/IF), Sao Paulo, SP (Brazil). Inst. de Fisica

    2014-07-01

    Tissue equivalent materials present a variety of uses, including routine quality assurance and quality control programs in both diagnostic and therapeutic physics. They are frequently used in research facilities to measure doses delivered to patients undergoing various clinical procedures. This work presents the development and evaluation of a tissue equivalent ionization chamber, with a sensitive volume of 2.3 cm{sup 3}, for routine use in X-rays beams. This ionization chamber was developed at the Calibration Laboratory/IPEN. The new tissue equivalent material was developed at the Physics Institute of the University of Sao Paulo. In order to evaluate the dosimetric performance of the new ionization chamber, several tests described by international standards were undertaken, and all results were within the recommended limits. (author)

  20. Using DCM pitch modulation and feedback to improve long term X-ray beam stability

    International Nuclear Information System (INIS)

    Bloomer, C; Dent, A; Diaz-Moreno, S; Dolbnya, I; Pedersen, U; Rehm, G; Tang, C; Thomas, C

    2013-01-01

    In this paper we demonstrate significant improvements to the stability of the monochromatic X-ray beam intensity on several beamlines at Diamond, using a modulation of the pitch axis of the DCM with a piezoelectric actuator. The modulation is detected on an intensity diagnostic (e.g. an ion chamber) using a software lock-in technique. The detected amplitude and phase are used in a feedback to keep the DCM at the peak of the rocking curve, or any arbitrary position 'off-peak' which might be desired to detune the DCM and reject unwanted harmonics. A major advantage of this software based system is the great flexibility offered, using standard, readily available instrumentation. Measurements of the short and long-term performance of the feedback on several beamlines are presented, and the limitations of such a feedback are discussed.

  1. Effect of dental metal in 10 MV X-ray beam therapy

    International Nuclear Information System (INIS)

    Mimura, Seiichi; Mikami, Yasutaka; Inamura, Keiji; Tahara, Seiji; Nagaya, Isao; Egusa, Tomomi; Nakagiri, Yoshitada; Sugita, Katsuhiko.

    1991-01-01

    We have often encountered patients with dental metal when employing the 10 MV X-ray beam therapy for head and neck tumors, and felt it important to investigate the effect of dental metal in relation to dose distribution. The absorbed dose rose abruptly in the vicinity of the metal reaching an interface value equal to 150% of the dose within the acrylic phantom. These results showed that an overdose occurred about 5 mm from the metal. We also learned that the overdose can be avoided by using a 5-mm thick tissue equivalent material. Six patients with dental metal were treated after first covering their metal with a 5-mm thick mouthpiece. No radiation stomatitis caused by the metal was observed in any of these cases. (author)

  2. The influence of an extrapolation chamber over the low energy X-ray beam radiation field

    Energy Technology Data Exchange (ETDEWEB)

    Tanuri de F, M. T.; Da Silva, T. A., E-mail: mttf@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear / CNEN, Av. Pte. Antonio Carlos 6627, 31270-901 Pampulha, Belo Horizonte, Minas Gerais (Brazil)

    2016-10-15

    The extrapolation chambers are detectors whose sensitive volume can be modified by changing the distance between the electrodes and has been widely used for beta particles primary measurement system. In this work, was performed a PTW 23392 extrapolation chamber Monte Carlo simulation, by mean the MCNPX code. Although the sensitive volume of an extrapolation chamber can be reduced to very small size, their packaging is large enough to modify the radiation field and change the absorbed dose measurements values. Experiments were performed to calculate correction factors for this purpose. The validation of the Monte Carlo model was done by comparing the spectra obtained with a CdTe detector according to the ISO 4037 criteria. Agreements smaller than 5% for half value layers, 10% for spectral resolution and 1% for mean energy, were found. It was verified that the correction factors are dependent of the X-ray beam quality. (Author)

  3. Excitation-resolved cone-beam x-ray luminescence tomography.

    Science.gov (United States)

    Liu, Xin; Liao, Qimei; Wang, Hongkai; Yan, Zhuangzhi

    2015-07-01

    Cone-beam x-ray luminescence computed tomography (CB-XLCT), as an emerging imaging technique, plays an important role in in vivo small animal imaging studies. However, CB-XLCT suffers from low-spatial resolution due to the ill-posed nature of reconstruction. We improve the imaging performance of CB-XLCT by using a multiband excitation-resolved imaging scheme combined with principal component analysis. To evaluate the performance of the proposed method, the physical phantom experiment is performed with a custom-made XLCT/XCT imaging system. The experimental results validate the feasibility of the method, where two adjacent nanophosphors (with an edge-to-edge distance of 2.4 mm) can be located.

  4. The influence of an extrapolation chamber over the low energy X-ray beam radiation field

    International Nuclear Information System (INIS)

    Tanuri de F, M. T.; Da Silva, T. A.

    2016-10-01

    The extrapolation chambers are detectors whose sensitive volume can be modified by changing the distance between the electrodes and has been widely used for beta particles primary measurement system. In this work, was performed a PTW 23392 extrapolation chamber Monte Carlo simulation, by mean the MCNPX code. Although the sensitive volume of an extrapolation chamber can be reduced to very small size, their packaging is large enough to modify the radiation field and change the absorbed dose measurements values. Experiments were performed to calculate correction factors for this purpose. The validation of the Monte Carlo model was done by comparing the spectra obtained with a CdTe detector according to the ISO 4037 criteria. Agreements smaller than 5% for half value layers, 10% for spectral resolution and 1% for mean energy, were found. It was verified that the correction factors are dependent of the X-ray beam quality. (Author)

  5. Evaluation of a tissue equivalent ionization chamber in X-ray beams

    International Nuclear Information System (INIS)

    Perini, Ana Paula; Neves, Lucio Pereira; Santos, William de Souza; Caldas, Linda V.E.; Frimaio, Audrew; Costa, Paulo R.

    2014-01-01

    Tissue equivalent materials present a variety of uses, including routine quality assurance and quality control programs in both diagnostic and therapeutic physics. They are frequently used in research facilities to measure doses delivered to patients undergoing various clinical procedures. This work presents the development and evaluation of a tissue equivalent ionization chamber, with a sensitive volume of 2.3 cm 3 , for routine use in X-rays beams. This ionization chamber was developed at the Calibration Laboratory/IPEN. The new tissue equivalent material was developed at the Physics Institute of the University of Sao Paulo. In order to evaluate the dosimetric performance of the new ionization chamber, several tests described by international standards were undertaken, and all results were within the recommended limits. (author)

  6. Dosimetry of x-ray beams: The measure of the problem

    International Nuclear Information System (INIS)

    de Castro, T.M.

    1986-08-01

    This document contains the text of an oral presentation on dosimetry of analytical x-ray equipment presented at the Denver X-Ray Conference. Included are discussions of sources of background radiation, exposure limits from occupational sources, and the relationship of these sources to the high dose source of x-rays found in analytical machines. The mathematical basis of x-ray dosimetry is reviewed in preparation for more detailed notes on personnel dosimetry and the selection of the most appropriate dosimeter for a specific application. The presentation concludes with a discussion common to previous x-ray equipment accidents. 2 refs

  7. Beam monitor system for an x-ray free electron laser and compact laser

    Directory of Open Access Journals (Sweden)

    Y. Otake

    2013-04-01

    Full Text Available A beam-monitor system for XFEL/SPring 8, “SACLA,” has been constructed. In order to maintain a stable self-amplified spontaneous emission (SASE interaction, the straightness and overlap of the axes to within 3  μm between the electron beams and the radiated x rays for an undulator section of about 100 m length is necessary. This straightness means relative alignment to an experimental target sample. Furthermore, a temporal stability of 30 fs in order to maintain a constant peak beam current is also necessary to conduct stable SASE lasing. The monitor system was developed to satisfy these spatial and temporal stability and resolution criteria. The system comprises spatial monitors, such as cavity-type beam-position monitors and screen monitors, as well as temporal measurement instruments, such as current monitors, waveguide spectrometers, coherent synchrotron-radiation detectors, a streak camera, and an rf deflector. Commissioning of SACLA started from March 2011, and the monitors performed sufficient roles to tune the beams for lasing. The achieved overall performances of the system, including data acquisition, are: the beam position monitor has a spatial resolution of 600 nm in rms; the bunch-length monitors show ability to observe bunch lengths from 1 ns in an injector with velocity bunching to less than 30 fs after three-stage bunch compressors. The less than 3  μm spatial resolution of the screen monitor was also confirmed during practical beam operation. Owing to these fulfilled performances, such as the high spatial and temporal resolutions, stable lasing of SACLA has been achieved.

  8. Characteristic parameters analysis on diagnostic X-ray beams for dosemeter calibration

    International Nuclear Information System (INIS)

    Oliveira, Paulo Marcio Campos de

    2008-01-01

    Ionizing radiation metrology is the base to achieve reliable dose measurements in ali areas; it is also part of the framework that is established to assure radiation protection procedures in order to avoid or minimize the harmful biological effect that may be caused by ionizing radiation. A well done metrology means the use of reliable instruments that comply with standard performance requirements worldwide accepted. Those instruments are expected to be calibrated by Metrology Laboratories under well defined conditions. The International Electrotechnical Commission (IEC) in Standard 61267 established the reference radiations for medical diagnostic x-ray equipment that are recommended to be used for calibrating dosimetric systems for diagnostic dosimetry. In this work, X-ray beam qualities were established in a Calibration Laboratory and their characteristics were analyzed through the measurement of beam parameters like inherent tube filtration, beam uniformity and field size, energy spectra and peak voltage for additional filtration with 94.425 por cent and 99.999 por cent purity filters. Also, the first half-value layer and the homogeneity coefficient were measured for the three RQR 2, RQR 6 and RQR 10 IEC beam qualities and they were analyzed according to the IEC standard. Air-kerma measurements were carried out with an ionization chamber that had its reliability confirmed through repetition and reproducibility reading tests. In 50 sets of measurements the maximum standard deviation found of 10 successive readings was 0.19 %; the maximum shift of the reading mean value at a fixed geometry condition was 0.80 % with an overall standard deviation of 0.23 %. Results showed that the use of different purity filters did not cause a relevant influence on the beam energy spectra. An ionization chamber was also calibrated against a standard dosimeter in ali implemented reference radiations and the relevant sources of uncertainties were estimated. Calibration could be done

  9. Time-resolved x-ray line emission studies of thermal transport in multiple beam uv-irradiated targets

    International Nuclear Information System (INIS)

    Jaanimagi, P.A.; Henke, B.L.; Delettrez, J.; Richardson, M.C.

    1984-01-01

    Thermal transport in spherical targets irradiated with multiple, nanosecond duration laser beams, has been a topic of much discussion recently. Different inferences on the level of thermal flux inhibition have been drawn from plasma velocity and x-ray spectroscopic diagnostics. We present new measurements of thermal transport on spherical targets made through time-resolved x-ray spectroscopic measurements of the progress of the ablation surface through thin layers of material on the surface of the target. These measurements, made with 6 and 12 uv (351 nm) nanosecond beams from OMEGA, will be compared to previous thermal transport measurements. Transparencies of the conference presentation are given

  10. Soft X-ray measurements for investigating the plasma focus dynamics

    International Nuclear Information System (INIS)

    Nahrath, B.

    In a Mather-type plasma focus short time soft x-ray pictures are taken by means of a double pinhole camera equipped with a pulsed channel plate and two different filters to study the local development of electron temperatures Tsub(e) with time resolution of 3 ns. Up to the maximum compression the measured Tsub(e) are roughly in accordance with the results of MHD-calculations. During a later phase, characterized by the occurence of m=O-instabilities, localized plasma regions with high densities and high electron temperatures Tsub(e) of about 600 eV (up to 1000 eV) are observed. Using the channel plate technique with increased sensivity a slowly decaying plasma with local Tsub(e)-values of about 300 eV and large diffuse structures is identified for several hundred nanoseconds. During this 'late phase' of the focus most of the neutron emission takes place. There is no correlation between the value of Tsub(e) and the rate of neutron emission. (orig.) [de

  11. Estimation of effective dose from limited cone beam X-ray CT examination

    Energy Technology Data Exchange (ETDEWEB)

    Iwai, Kazuo; Arai, Yoshinori; Hashimoto, Koji [Nihon Univ., Tokyo (Japan). School of Dentistry; Nishizawa, Kanae

    2000-12-01

    The limited cone beam X-ray CT (Ortho-CT) was developed on the basis of multi-functional panoramic apparatus, SCANORA (Soredex Co. Helsinki Finland). The imaging intensifier (I.I.) was built in this apparatus as a X-ray detection device instead of X-ray film. The signal provided from I.I. was converted from analog into digital by an analog-digital converter and image reconstitution was done as a three-directional image of the dimensions 3.8 cm of width, 3.0 cm height and 3.8 cm depth with the personal computer. The 3DX Multi image micro CT'' (3DX) was developed along similar lines by MORITA Co., Ltd. (Kyoto, JAPAN). In this study, the stochastic effect on organ and tissue caused by examinations using Ortho-CT and 3DX was measured. The effective dose was estimated according to the recommendation of ICRP60 and was compared with those of panoramic radiography and computed tomography. The irradiation conditions were as follows: 85 kV, 10 mA with the filtration of 3 mmAl and added 1 mmCu for Ortho-CT, and 80 kV, 2 mA and the filtration of 3.1 mmAL for 3DX. The measurement of organ and tissue dose was performed using an anthropomorphic Rando woman phantom (Alderson Research Laboratories Co., Stanfora, CN), as well as by using two different type of thermoluminescent dosimeter (TLD); Panasonic UD-170A (BeO) and UD-110S (CaSO{sub 4}: Tm). The UD-170A was for dose measurement of the inner useful X-ray beams, while the UD-110S was for outer beams. The measured organ and tissue were those recommended with ICRP60 (gonad, breast, bone marrow, lung, thyroid gland, esophagus, stomach, colon, liver, bladder, skin, brain, thymus, adrenal, kidney, spleen, pancrease, upper large intestine, uterus, eyes and major salivary gland). The imaging by Orhto-CT was made in the left maxillary 1st molar, left mandibular 1st molar and temporomandibular joint. 3DX measurement was made in the maxillary incisor region and middle ear regions other than the regions mentioned above. The skin

  12. Design and performance of coded aperture optical elements for the CESR-TA x-ray beam size monitor

    Energy Technology Data Exchange (ETDEWEB)

    Alexander, J.P.; Chatterjee, A.; Conolly, C.; Edwards, E.; Ehrlichman, M.P. [Cornell University, Ithaca, NY 14853 (United States); Flanagan, J.W. [High Energy Accelerator Research Organization (KEK), Tsukuba (Japan); Department of Accelerator Science, Graduate University for Advanced Studies (SOKENDAI), Tsukuba (Japan); Fontes, E. [Cornell University, Ithaca, NY 14853 (United States); Heltsley, B.K., E-mail: bkh2@cornell.edu [Cornell University, Ithaca, NY 14853 (United States); Lyndaker, A.; Peterson, D.P.; Rider, N.T.; Rubin, D.L.; Seeley, R.; Shanks, J. [Cornell University, Ithaca, NY 14853 (United States)

    2014-12-11

    We describe the design and performance of optical elements for an x-ray beam size monitor (xBSM), a device measuring e{sup +} and e{sup −} beam sizes in the CESR-TA storage ring. The device can measure vertical beam sizes of 10–100μm on a turn-by-turn, bunch-by-bunch basis at e{sup ±} beam energies of ∼2–5GeV. x-rays produced by a hard-bend magnet pass through a single- or multiple-slit (coded aperture) optical element onto a detector. The coded aperture slit pattern and thickness of masking material forming that pattern can both be tuned for optimal resolving power. We describe several such optical elements and show how well predictions of simple models track measured performances. - Highlights: • We characterize optical element performance of an e{sup ±} x-ray beam size monitor. • We standardize beam size resolving power measurements to reference conditions. • Standardized resolving power measurements compare favorably to model predictions. • Key model features include simulation of photon-counting statistics and image fitting. • Results validate a coded aperture design optimized for the x-ray spectrum encountered.

  13. Hard X-ray dose intensity and spatial distribution in a plasma focus ...

    Indian Academy of Sciences (India)

    Roomi et al [17] studied the effect of applied voltage and nitrogen gas pressure ... optimum conditions for X-ray production; their results showed that at each discharge ..... [23] G Foldiak, Industrial application of radioisotopes (Elsevier Science, ...

  14. Using of a microcapillary refractive X-ray lens for focusing and imaging

    Energy Technology Data Exchange (ETDEWEB)

    Dudchik, Yu.I. [Institute of Applied Physics Problems, Kurchatova 7, 220064, Minsk (Belarus)], E-mail: dudchik@bsu.by; Komarov, F.F. [Institute of Applied Physics Problems, Kurchatova 7, 220064, Minsk (Belarus); Piestrup, M.A. [Adelphi Technology, 981-B Industrial Rd, San Carlos, 94070, California (United States)], E-mail: melpie@adelphitech.com; Gary, C.K.; Park, H.; Cremer, J.T. [Adelphi Technology, 981-B Industrial Rd, San Carlos, 94070, California (United States)

    2007-07-15

    The microcapillary lens, formed by air bubbles in a hollow core glass capillary filled with epoxy, is a novel design of a compound refractive lens for X-rays. The epoxy enclosed between two air bubbles has the form of a biconcave lens and acts as a positive lens for X-rays. Each individual lens is spherical with radius of curvature equal to the inner radius of the capillary. Up to 500 individual biconcave lenses can be formed in a single capillary with diameters from 50 to 500 {mu}m. Due to the small radius of curvatures that can be achieved, microcapillary lenses typically have shorter focal lengths than those made by compression or injection molding. For example, microcapillary lenses with a focal length about 5 cm for 8 keV X-rays and 50-micron aperture are readily available. We have produced a set of lenses in a 200-micron inner-diameter glass capillary with 100-350 individual microlenses and measured their parameters at the Stanford Synchrotron Radiation Laboratory and at the Advanced Photon Source. Our investigations have also shown that the lenses are suitable for imaging applications with an X-ray tube as a source of X-rays. A simple X-ray microscope is discussed. The microscope consists of a copper anode X-ray tube, X-ray lens and CCD-camera. The object, lens and CCD-camera were placed in-line at distances to satisfy the lens formula. It is shown that the field of view of the microscope is about 1 mm and resolution is equal to 3-5 {mu}m.

  15. Multi-mounted X-ray cone-beam computed tomography

    Science.gov (United States)

    Fu, Jian; Wang, Jingzheng; Guo, Wei; Peng, Peng

    2018-04-01

    As a powerful nondestructive inspection technique, X-ray computed tomography (X-CT) has been widely applied to clinical diagnosis, industrial production and cutting-edge research. Imaging efficiency is currently one of the major obstacles for the applications of X-CT. In this paper, a multi-mounted three dimensional cone-beam X-CT (MM-CBCT) method is reported. It consists of a novel multi-mounted cone-beam scanning geometry and the corresponding three dimensional statistical iterative reconstruction algorithm. The scanning geometry is the most iconic design and significantly different from the current CBCT systems. Permitting the cone-beam scanning of multiple objects simultaneously, the proposed approach has the potential to achieve an imaging efficiency orders of magnitude greater than the conventional methods. Although multiple objects can be also bundled together and scanned simultaneously by the conventional CBCT methods, it will lead to the increased penetration thickness and signal crosstalk. In contrast, MM-CBCT avoids substantially these problems. This work comprises a numerical study of the method and its experimental verification using a dataset measured with a developed MM-CBCT prototype system. This technique will provide a possible solution for the CT inspection in a large scale.

  16. Optical and mechanical design of the extended x-ray absorption fine structure (EXAFS) beam-line at Indus-II synchrotron source

    International Nuclear Information System (INIS)

    Das, N.C.; Jha, S.N.; Bhattacharyya, D.; Sinha, A.K.; Mishra, V.K.; Verma, Vishnu; Ghosh, A.K.

    2002-11-01

    An extended x-ray absorption fine structure (EXAFS) beam line for x-ray absorption studies using energy dispersive geometry and position sensitive detector is being designed for the INDUS-II Synchrotron source. The beam line would be used for doing x-ray absorption experiments involving measurements of fme structures above the absorption edge of different species of atoms in a material The results of the above experiments would lead to the determination of different important structural parameters of materials viz.. inter-atomic distance. co-ordination number, degree of disorder and radial distribution function etc. The optical design of the beam line has been completed based on the working principle that a single crystal bent in the shape of an ellipse by a crystal bender would act as a dispersing as well as focusing element. The mechanical design of the beam line including the crystal bender has also been completed and discussed here. Calculations have been done to detennine the temperature profile on the different components of the beam line under exposure to synchrotron radiation and proper cooling channels have been designed to bring down the heat load on the components. (author)

  17. Simulation of enhanced characteristic x rays from a 40-MeV electron beam laser accelerated in plasma

    Directory of Open Access Journals (Sweden)

    L. Nikzad

    2012-02-01

    Full Text Available Simulation of x-ray generation from bombardment of various solid targets by quasimonoenergetic electrons is considered. The electron bunches are accelerated in a plasma produced by interaction of 500 mJ, 30 femtosecond laser pulses with a helium gas jet. These relativistic electrons propagate in the ion channel generated in the wake of the laser pulse. A beam of MeV electrons can interact with targets to generate x-ray radiation with keV energy. The MCNP-4C code based on Monte Carlo simulation is employed to compare the production of bremsstrahlung and characteristic x rays between 10 and 100 keV by using two quasi-Maxwellian and quasimonoenergetic energy distributions of electrons. For a specific electron spectrum and a definite sample, the maximum x-ray flux varies with the target thickness. Besides, by increasing the target atomic number, the maximum x-ray flux is increased and shifted towards a higher energy level. It is shown that by using the quasimonoenergetic electron profile, a more intense x ray can be produced relative to the quasi-Maxwellian profile (with the same total energy, representing up to 77% flux enhancement at K_{α} energy.

  18. Characteristics of kilovoltage x-ray beams used for cone-beam computed tomography in radiation therapy

    International Nuclear Information System (INIS)

    Ding, George X; Duggan, Dennis M; Coffey, Charles W

    2007-01-01

    The purpose of this investigation is to characterize the beams produced by a kilovoltage (kV) imager integrated into a linear accelerator (Varian on-board imager integrated into the Trilogy accelerator) for acquiring high resolution volumetric cone-beam computed tomography (CBCT) images of the patient on the treatment table. The x-ray tube is capable of generating photon spectra with kVp values between 40 and 125 kV. The Monte Carlo simulations were used to study the characteristics of kV beams and the properties of imaged target scatters. The Monte Carlo results were benchmarked against measurements, and excellent agreements were obtained. We also studied the effect of including the electron impact ionization (EII), and the simulation showed that the characteristic radiation is increased significantly in the energy spectra when EII is included. Although only slight beam hardening is observed in the spectra of all photons after passing through the phantom target, there is a significant difference in the spectra and angular distributions between scattered and primary photons. The results also show that the photon fluence distributions are significantly altered by adding bow tie filters. The results indicate that a combination of large cone-beam field size and large imaged target significantly increases scatter-to-primary ratios for photons that reach the detector panel. For phantoms 10 cm, 20 cm and 30 cm thick of water placed at the isocentre, the scatter-to-primary ratios are 0.94, 3.0 and 7.6 respectively for an open 125 kVp CBCT beam. The Monte Carlo simulations show that the increase of the scatter is proportional to the increase of the imaged volume, and this also applies to scatter-to-primary ratios. This study shows both the magnitude and the characteristics of scattered x-rays. The knowledge obtained from this investigation may be useful in the future design of the image detector to improve the image quality

  19. Modelling properties of hard x-rays generated by the interaction between relativistic electrons and very intense laser beams

    International Nuclear Information System (INIS)

    Popa, Alexandru

    2009-01-01

    In a previous paper we presented a calculation model for high harmonic generation by relativistic Thomson scattering of the electromagnetic radiation by free electrons. In this paper we present a similar model for the calculation of the energies of hard x-rays (20- 200 keV) resulted from the interaction between relativistic electrons (20-100 MeV) and very intense laser beams. Starting from the relativistic equations of motion of an electron in the electromagnetic field we show that the Lienard-Wiechert equation leads to electromagnetic waves whose frequencies are in the domain of hard x-rays. When the relativistic parameter of the laser beam is greater than unity, the model predicts the existence of harmonics of the above frequencies. Our theoretical values are in good agreement with experimental values of the x-ray energies from the literature and predict accurately their angular distribution.

  20. Glass capillary optics for making x-ray beams of 0.1 to 50 microns diameter

    International Nuclear Information System (INIS)

    Bilderback, Donald H.; Fontes, Ernest

    1997-01-01

    We have fabricated a unique computerized glass puller that can make parabolic or elliptically tapered glass capillaries for microbeam x-ray experiments from hollow glass tubing. We have produced optics that work in a single-bounce imaging mode or in a multi-bounce condensing mode. The imaging-mode capillaries have been used to create 20 to 50 micron diameter x-ray beams at 12 keV that are quite useful for imaging diffraction patterns from tiny bundles of carbon and Kevlar fibers. The condensing-mode capillaries are useful for creating submicron diameter beams and show great promise in x-ray fluorescence applications with femtogram sensitivity for patterned Er and Ti dopants diffused into an optically-active lithium niobate wafer

  1. Shielding requirements for constant-potential diagnostic x-ray beams determined by a Monte Carlo calculation

    International Nuclear Information System (INIS)

    Simpkin, D.J.

    1989-01-01

    A Monte Carlo calculation has been performed to determine the transmission of broad constant-potential x-ray beams through Pb, concrete, gypsum wallboard, steel and plate glass. The EGS4 code system was used with a simple broad-beam geometric model to generate exposure transmission curves for published 70, 100, 120 and 140-kVcp x-ray spectra. These curves are compared to measured three-phase generated x-ray transmission data in the literature and found to be reasonable. For calculation ease the data are fit to an equation previously shown to describe such curves quite well. These calculated transmission data are then used to create three-phase shielding tables for Pb and concrete, as well as other materials not available in Report No. 49 of the NCRP

  2. Shielding requirements for constant-potential diagnostic x-ray beams determined by a Monte Carlo calculation.

    Science.gov (United States)

    Simpkin, D J

    1989-02-01

    A Monte Carlo calculation has been performed to determine the transmission of broad constant-potential x-ray beams through Pb, concrete, gypsum wallboard, steel and plate glass. The EGS4 code system was used with a simple broad-beam geometric model to generate exposure transmission curves for published 70, 100, 120 and 140-kVcp x-ray spectra. These curves are compared to measured three-phase generated x-ray transmission data in the literature and found to be reasonable. For calculation ease the data are fit to an equation previously shown to describe such curves quite well. These calculated transmission data are then used to create three-phase shielding tables for Pb and concrete, as well as other materials not available in Report No. 49 of the NCRP.

  3. Development of a PIXE (Particle Induced X-ray Emission) analysis device using an extracted proton beam

    International Nuclear Information System (INIS)

    Saidi, A.

    1989-01-01

    The experimental device described allows the extention of the PIXE (Particle Induced X-ray Emission) method to the analysis, by means of proton beams, of solid or liquid samples, which can not be analyzed under vacuum conditions. The homogeneity of the surfaces to be analysed and elements (in the atmosphere) which absorb X-rays must be taken into account. Liquid samples do not need special care. The results show that: at high energies, the extracted beam sensibility is of the same order of magnitude as those obtained under vacuum; at low energies, the performance under vacuum conditions is better. The particles energy losses, at the exit membrane and in the outer atmosphere, decrease the X-rays production efficiency [fr

  4. THE FIRST FOCUSED HARD X-RAY IMAGES OF THE SUN WITH NuSTAR

    Energy Technology Data Exchange (ETDEWEB)

    Grefenstette, Brian W.; Madsen, Kristin K.; Forster, Karl; Harrison, Fiona A. [Cahill Center for Astrophysics, 1216 E. California Blvd, California Institute of Technology, Pasadena, CA 91125 (United States); Glesener, Lindsay [School of Physics and Astronomy, University of Minnesota—Twin Cities, Minneapolis, MN 55455 (United States); Krucker, Säm; Hudson, Hugh; Boggs, Steven E.; Craig, William W. [Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States); Hannah, Iain G. [SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Smith, David M.; Marsh, Andrew J. [Physics Department and Santa Cruz Institute for Particle Physics, University of California, Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States); Vogel, Julia K. [Physics Division, Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); White, Stephen M. [Air Force Research Laboratory, Albuquerque, NM (United States); Caspi, Amir [Southwest Research Institute, Boulder, CO 80302 (United States); Chen, Bin [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Shih, Albert [Solar Physics Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Kuhar, Matej [University of Applied Sciences and Arts Northwestern Switzerland, CH-5210 Windisch (Switzerland); Christensen, Finn E. [DTU Space, National Space Institute, Technical University of Denmark, Elektrovej 327, DK-2800 Lyngby (Denmark); Hailey, Charles J., E-mail: bwgref@srl.caltech.edu [Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); and others

    2016-07-20

    We present results from the the first campaign of dedicated solar observations undertaken by the Nuclear Spectroscopic Telescope ARray ( NuSTAR ) hard X-ray (HXR) telescope. Designed as an astrophysics mission, NuSTAR nonetheless has the capability of directly imaging the Sun at HXR energies (>3 keV) with an increase in sensitivity of at least two magnitude compared to current non-focusing telescopes. In this paper we describe the scientific areas where NuSTAR will make major improvements on existing solar measurements. We report on the techniques used to observe the Sun with NuSTAR , their limitations and complications, and the procedures developed to optimize solar data quality derived from our experience with the initial solar observations. These first observations are briefly described, including the measurement of the Fe K-shell lines in a decaying X-class flare, HXR emission from high in the solar corona, and full-disk HXR images of the Sun.

  5. The First Focused Hard X-Ray Images of the Sun with NuSTAR

    Science.gov (United States)

    Grefenstette, Brian W.; Glesener, Lindsay; Kruckner, Sam; Hudson, Hugh; Hannah, Iain G.; Smith, David M.; Vogel, Julia K.; White, Stephen M.; Madsen, Kristin K.; Marsh, Andrew J.; hide

    2016-01-01

    We present results from the first campaign of dedicated solar observations undertaken by the Nuclear Spectroscopic Telescope ARray (NuSTAR) hard X-ray (HXR) telescope. Designed as an astrophysics mission, NuSTAR nonetheless has the capability of directly imaging the Sun at HXR energies (3 keV) with an increase in sensitivity of at least two magnitude compared to current non-focusing telescopes. In this paper we describe the scientific areas where NuSTAR will make major improvements on existing solar measurements. We report on the techniques used to observe the Sun with NuSTAR, their limitations and complications, and the procedures developed to optimize solar data quality derived from our experience with the initial solar observations. These first observations are briefly described, including the measurement of the Fe K-shell lines in a decaying X-class flare, HXR emission from high in the solar corona, and full-disk HXR images of the Sun.

  6. Reduction of variable-truncation artifacts from beam occlusion during in situ x-ray tomography

    Science.gov (United States)

    Borg, Leise; Jørgensen, Jakob S.; Frikel, Jürgen; Sporring, Jon

    2017-12-01

    Many in situ x-ray tomography studies require experimental rigs which may partially occlude the beam and cause parts of the projection data to be missing. In a study of fluid flow in porous chalk using a percolation cell with four metal bars drastic streak artifacts arise in the filtered backprojection (FBP) reconstruction at certain orientations. Projections with non-trivial variable truncation caused by the metal bars are the source of these variable-truncation artifacts. To understand the artifacts a mathematical model of variable-truncation data as a function of metal bar radius and distance to sample is derived and verified numerically and with experimental data. The model accurately describes the arising variable-truncation artifacts across simulated variations of the experimental setup. Three variable-truncation artifact-reduction methods are proposed, all aimed at addressing sinogram discontinuities that are shown to be the source of the streaks. The ‘reduction to limited angle’ (RLA) method simply keeps only non-truncated projections; the ‘detector-directed smoothing’ (DDS) method smooths the discontinuities; while the ‘reflexive boundary condition’ (RBC) method enforces a zero derivative at the discontinuities. Experimental results using both simulated and real data show that the proposed methods effectively reduce variable-truncation artifacts. The RBC method is found to provide the best artifact reduction and preservation of image features using both visual and quantitative assessment. The analysis and artifact-reduction methods are designed in context of FBP reconstruction motivated by computational efficiency practical for large, real synchrotron data. While a specific variable-truncation case is considered, the proposed methods can be applied to general data cut-offs arising in different in situ x-ray tomography experiments.

  7. Detector, collimator and real-time reconstructor for a new scanning-beam digital x-ray (SBDX) prototype.

    Science.gov (United States)

    Speidel, Michael A; Tomkowiak, Michael T; Raval, Amish N; Dunkerley, David A P; Slagowski, Jordan M; Kahn, Paul; Ku, Jamie; Funk, Tobias

    Scanning-beam digital x-ray (SBDX) is an inverse geometry fluoroscopy system for low dose cardiac imaging. The use of a narrow scanned x-ray beam in SBDX reduces detected x-ray scatter and improves dose efficiency, however the tight beam collimation also limits the maximum achievable x-ray fluence. To increase the fluence available for imaging, we have constructed a new SBDX prototype with a wider x-ray beam, larger-area detector, and new real-time image reconstructor. Imaging is performed with a scanning source that generates 40,328 narrow overlapping projections from 71 × 71 focal spot positions for every 1/15 s scan period. A high speed 2-mm thick CdTe photon counting detector was constructed with 320×160 elements and 10.6 cm × 5.3 cm area (full readout every 1.28 μs), providing an 86% increase in area over the previous SBDX prototype. A matching multihole collimator was fabricated from layers of tungsten, brass, and lead, and a multi-GPU reconstructor was assembled to reconstruct the stream of captured detector images into full field-of-view images in real time. Thirty-two tomosynthetic planes spaced by 5 mm plus a multiplane composite image are produced for each scan frame. Noise equivalent quanta on the new SBDX prototype measured 63%-71% higher than the previous prototype. X-ray scatter fraction was 3.9-7.8% when imaging 23.3-32.6 cm acrylic phantoms, versus 2.3-4.2% with the previous prototype. Coronary angiographic imaging at 15 frame/s was successfully performed on the new SBDX prototype, with live display of either a multiplane composite or single plane image.

  8. X-ray tubes

    International Nuclear Information System (INIS)

    Young, R.W.

    1979-01-01

    A form of x-ray tube is described which provides satisfactory focussing of the electron beam when the beam extends for several feet from gun to target. Such a tube can be used for computerised tomographic scanning. (UK)

  9. Dense plasma focus PACO as a hard X-ray emitter: a study on the radiation source

    OpenAIRE

    Supán, L.; Guichón, S.; Milanese, Maria Magdalena; Niedbalski, Jorge Julio; Moroso, Roberto Luis; Acuña, H.; Malamud, Florencia

    2016-01-01

    The radiation in the X-ray range detected outside the vacuum chamber of the dense plasma focus (DPF) PACO, are produced on the anode zone. The zone of emission is studied in a shot-to-shot analysis, using pure deuterium as filling gas. We present a diagnostic method to determine the place and size of the hard X-ray source by image analysis of high density radiography plates. Fil: Supán, L.. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Insti...

  10. Performance test for implantation of a primary standard of low energy X-ray beams

    International Nuclear Information System (INIS)

    Cardoso, Ricardo de Souza; Bossio, Francisco; Peixoto, Jose Guilherme P.

    2005-01-01

    The implementation of a standard laboratory of calibration chambers that will serve to radiotherapy activities, radiodiagnosis and radioprotection, depends on the knowledge of physical and dosimetric parameters that characterize the quality of the radiation beam. With the aim of verifying the reliability of the ionizing free-air chamber with variable volume manufactured by Victoreen Instruments, model 481, as a primary standard, a study of the performance of the chamber to x-rays qualities of low energy was developed in this work. These qualities are the ones recommended by 'Bureau International des Poids et Mesures' - BIPM, for daily routine of the calibration service performed by the 'Laboratorio Nacional de Metrologia das Radiacoes Ionizantes - LNMRI/IRD, for calibration of this secondary standard chambers that serve to the control in hospitals, clinics and industries. The results obtained at the present work show that the Victoreen chamber model 481 behaves as a primary standard, being easy to handle and having simple mechanical construction, and showing an expanded uncertainty equal to 0,26%, regarding the quality of the radiation beam of 30 kV. However, some of the equipment used at the present study need to be submitted to a strict routine calibration, in order for the laboratory to be in accordance with the recommendations of the standard ABNT -NBR ISO/IEC 17025 (2003). (author)

  11. Correlation of electron beams and hard x-ray emissions in ISTTOK Tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Jakubowski, L.; Malinowski, K.; Sadowski, M.J.; Zebrowski, J.; Rabinski, M.; Jakubowski, M.J. [National Centre for Nuclear Research (NCBJ), Otwock (Poland); Plyusnin, V.V.; Fernandes, H.; Silva, C.; Duarte, P. [Association Euratom/IST, Instituto de Plasmas e Fusao Nuclear, Instituto Superior Tecnico, Lisboa (Portugal)

    2013-11-15

    The paper reports on experimental studies of electron beams in the ISTTOK tokamak, those were performed by means of an improved four-channel detector. The Cherenkov-type detector measuring head was equipped with four radiators made of two types of alumina-nitrate (AlN) poly-crystals: machinable and translucent ones, both of 10 mm in diameter and 2.5 mm in thickness. The movable support that enabled the whole detectors to be placed inside the tokamak vacuum chamber, at chosen positions along the ISTTOK minor radius. Since the electron energy distribution is one of the most important characteristics of tokamak plasmas, the main aim of the study was to perform estimations of an energy spectrum of the recorded electrons. For this purpose the radiators were coated with molybdenum (Mo) layers of different thickness. The technique based on the use of Cherenkov-type detectors enabled the detection of fast electrons (of energy above 66 keV) and determination of their spatial and temporal characteristics in the ISTTOK experiment. Measurements of hard X-rays (HXR), which were emitted during ISTTOK discharges, have also been performed. Particular attention was paid to the correlation measurements of HXR pulses with run-away electron beams. (copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  12. Measurements and simulations of focused beam for orthovoltage therapy

    International Nuclear Information System (INIS)

    Abbas, Hassan; Mahato, Dip N.; Satti, Jahangir; MacDonald, C. A.

    2014-01-01

    Purpose: Megavoltage photon beams are typically used for therapy because of their skin-sparing effect. However, a focused low-energy x-ray beam would also be skin sparing, and would have a higher dose concentration at the focal spot. Such a beam can be produced with polycapillary optics. MCNP5 was used to model dose profiles for a scanned focused beam, using measured beam parameters. The potential of low energy focused x-ray beams for radiation therapy was assessed. Methods: A polycapillary optic was used to focus the x-ray beam from a tungsten source. The optic was characterized and measurements were performed at 50 kV. PMMA blocks of varying thicknesses were placed between optic and the focal spot to observe any variation in the focusing of the beam after passing through the tissue-equivalent material. The measured energy spectrum was used to model the focused beam in MCNP5. A source card (SDEF) in MCNP5 was used to simulate the converging x-ray beam. Dose calculations were performed inside a breast tissue phantom. Results: The measured focal spot size for the polycapillary optic was 0.2 mm with a depth of field of 5 mm. The measured focal spot remained unchanged through 40 mm of phantom thickness. The calculated depth dose curve inside the breast tissue showed a dose peak several centimeters below the skin with a sharp dose fall off around the focus. The percent dose falls below 10% within 5 mm of the focus. It was shown that rotating the optic during scanning would preserve the skin-sparing effect of the focused beam. Conclusions: Low energy focused x-ray beams could be used to irradiate tumors inside soft tissue within 5 cm of the surface

  13. Carbon-ion beam irradiation kills X-ray-resistant p53-null cancer cells by inducing mitotic catastrophe.

    Directory of Open Access Journals (Sweden)

    Napapat Amornwichet

    Full Text Available BACKGROUND AND PURPOSE: To understand the mechanisms involved in the strong killing effect of carbon-ion beam irradiation on cancer cells with TP53 tumor suppressor gene deficiencies. MATERIALS AND METHODS: DNA damage responses after carbon-ion beam or X-ray irradiation in isogenic HCT116 colorectal cancer cell lines with and without TP53 (p53+/+ and p53-/-, respectively were analyzed as follows: cell survival by clonogenic assay, cell death modes by morphologic observation of DAPI-stained nuclei, DNA double-strand breaks (DSBs by immunostaining of phosphorylated H2AX (γH2AX, and cell cycle by flow cytometry and immunostaining of Ser10-phosphorylated histone H3. RESULTS: The p53-/- cells were more resistant than the p53+/+ cells to X-ray irradiation, while the sensitivities of the p53+/+ and p53-/- cells to carbon-ion beam irradiation were comparable. X-ray and carbon-ion beam irradiations predominantly induced apoptosis of the p53+/+ cells but not the p53-/- cells. In the p53-/- cells, carbon-ion beam irradiation, but not X-ray irradiation, markedly induced mitotic catastrophe that was associated with premature mitotic entry with harboring long-retained DSBs at 24 h post-irradiation. CONCLUSIONS: Efficient induction of mitotic catastrophe in apoptosis-resistant p53-deficient cells implies a strong cancer cell-killing effect of carbon-ion beam irradiation that is independent of the p53 status, suggesting its biological advantage over X-ray treatment.

  14. Fluorescence detection of white-beam X-ray absorption anisotropy: towards element-sensitive projections of local atomic structure

    International Nuclear Information System (INIS)

    Korecki, P.; Tolkiehn, M.; Dąbrowski, K. M.; Novikov, D. V.

    2011-01-01

    A method for a direct measurement of X-ray projections of the atomic structure is described. Projections of the atomic structure around Nb atoms in a LiNbO 3 single crystal were obtained from a white-beam X-ray absorption anisotropy pattern detected using Nb K fluorescence. Projections of the atomic structure around Nb atoms in a LiNbO 3 single crystal were obtained from a white-beam X-ray absorption anisotropy (XAA) pattern detected using Nb K fluorescence. This kind of anisotropy results from the interference of X-rays inside a sample and, owing to the short coherence length of a white beam, is visible only at small angles around interatomic directions. Consequently, the main features of the recorded XAA corresponded to distorted real-space projections of dense-packed atomic planes and atomic rows. A quantitative analysis of XAA was carried out using a wavelet transform and allowed well resolved projections of Nb atoms to be obtained up to distances of 10 Å. The signal of nearest O atoms was detected indirectly by a comparison with model calculations. The measurement of white-beam XAA using characteristic radiation indicates the possibility of obtaining element-sensitive projections of the local atomic structure in more complex samples

  15. Development of a Reference System for the determination of the personal dose equivalent and the constancy of X- Ray beams

    International Nuclear Information System (INIS)

    Vivolo, Vitor

    2006-01-01

    A reference system for the determination of the personal dose equivalent, Hp (10), and a quality control program of X-ray equipment used In radioprotection require the periodic verification of the X-ray beams constancy. In this work, two parallel-plate ionization chambers were developed with inner electrodes of different materials, and inserted into PMMA slab phantoms. One ionization chamber was developed with inner carbon electrodes and the other with inner aluminium electrodes. The two ionization chambers can be used as a Tandem system. The different energy response of the two ionization chambers allowed the development of the Tandem system that is very useful for the checking of the constancy of beam qualities. Standard intermediary energy X-ray beams (from 48 keV to 118 keV), radioprotection level, were established through the development of a dosimetric methodology and the analysis of their physical parameters. The ionization chambers were studied in relation to their operational characteristics, and they were calibrated in X-ray beams (radioprotection, diagnostic radiology, mammography and radiotherapy levels) in accordance to international recommendations. They presented good performance. The determination procedure of personal dose equivalent, Hp (10), was established. (author)

  16. 77 FR 12226 - Sadex Corp.; Filing of Food Additive Petition (Animal Use); Electron Beam and X-Ray Sources for...

    Science.gov (United States)

    2012-02-29

    ... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration 21 CFR Part 579 [Docket No. FDA-2012-F-0178] Sadex Corp.; Filing of Food Additive Petition (Animal Use); Electron Beam and X-Ray... Sadex Corp. has filed a petition proposing that the food additive regulations be amended to provide for...

  17. Dosimetry and monitoring of X-rays narrow beams produced by linear particle accelerator, for using in radiosurgery

    International Nuclear Information System (INIS)

    Campos, J.C.F.; Vizeu, D.M.

    1987-01-01

    The main characteristics of X-rays narrow beams dosimetry and monitoring are examined, aiming the introduction of this system in brain radiosurgery. The non-protocolize detectors are used, once that the detectors used in therapy by megavoltage were projected for dosimetry with an irradiation field above 40 mm diameter. (C.G.C.) [pt

  18. Micronuclei in human peripheral blood lymphocytes exposed to mixed beams of X-rays and alpha particles

    Czech Academy of Sciences Publication Activity Database

    Staaf, E.; Brehwens, K.; Haghdoost, S.; Nievaart, S.; Pachnerová Brabcová, Kateřina; Czub, J.; Braziewicz, J.; Wojcik, A.

    2012-01-01

    Roč. 51, č. 3 (2012), s. 283-293 ISSN 0301-634X Institutional research plan: CEZ:AV0Z10480505 Keywords : Micronuclei * LET * Combined exposure * Mixed beams * Alpha particles * X-rays Subject RIV: BO - Biophysics Impact factor: 1.754, year: 2012

  19. Proton- and x-ray beams generated by ultra-fast CO2 lasers for medical applications

    Science.gov (United States)

    Pogorelsky, Igor; Polyanskiy, Mikhail; Yakimenko, Vitaly; Ben-Zvi, Ilan; Shkolnikov, Peter; Najmudin, Zulfikar; Palmer, Charlotte A. J.; Dover, Nicholas P.; Oliva, Piernicola; Carpinelli, Massimo

    2011-05-01

    Recent progress in using picosecond CO2 lasers for Thomson scattering and ion-acceleration experiments underlines their potentials for enabling secondary radiation- and particle- sources. These experiments capitalize on certain advantages of long-wavelength CO2 lasers, such as higher number of photons per energy unit, and favorable scaling of the electrons' ponderomotive energy and critical plasma density. The high-flux x-ray bursts produced by Thomson scattering of the CO2 laser off a counter-propagating electron beam enabled high-contrast, time-resolved imaging of biological objects in the picosecond time frame. In different experiments, the laser, focused on a hydrogen jet, generated monoenergetic proton beams via the radiation-pressure mechanism. The strong power-scaling of this regime promises realization of proton beams suitable for laser-driven proton cancer therapy after upgrading the CO2 laser to sub-PW peak power. This planned improvement includes optimizing the 10-μm ultra-short pulse generation, assuring higher amplification in the CO2 gas under combined isotopic- and power-broadening effects, and shortening the postamplification pulse to a few laser cycles (150-200 fs) via chirping and compression. These developments will move us closer to practical applications of ultra-fast CO2 lasers in medicine and other areas.

  20. X-ray computed tomography imaging method which is immune to beam hardening effect

    International Nuclear Information System (INIS)

    Kanno, Ikuo; Uesaka, Akio; Nomiya, Seiichiro; Onabe, Hideaki

    2009-01-01

    For the easy treatment of cancers, early finding of them is an important theme of study. X-ray transmission measurement and computed tomography (CT) are powerful tools for finding cancers. The x-ray CT shows cross sectional view of human body and is able to detect small cancers such as 1 cm in diameter. The CT, however, gives very high dose exposure to human body: some 10 to 1000 times higher dose exposure than the chest radiography. It is not possible to have medical health check using CT frequently, in view of both individual and public accumulated dose exposures. The authors have been working on the reduction of dose exposure in x-ray transmission measurements in case of detecting iodine contrast media, which concentrates in cancers. In our method, energy information of x-rays is employed: in conventional x-ray transmission measurements, x-rays are measured as current and the energy of each x-ray is ignored. The numbers of x-ray events, φ 1 and φ 2 , of which energies are lower and higher than the one of iodine K-edge, respectively, are used for the estimation of iodine thickness in cancers. Moreover, high energy x-rays, which are not sensitive to the absorption by iodine, are cut by a filter made of higher atomic number material than iodine. We call this method filtered x-ray energy subtraction (FIX-ES) method. This FIX-ES method was shown twice as sensitive to iodine than current measurement method. With the choice of filter thickness, minimum dose exposure in FIX-ES is 30% of that when white x-rays are employed. In the study described above, we concentrated on the observation of cancer part. In this study, a cancer phantom in normal tissue is observed by FIX-ES method. The results are compared with the ones obtained by current measurement method. (author)

  1. X-ray diffraction imaging with the Multiple Inverse Fan Beam topology: Principles, performance and potential for security screening

    Energy Technology Data Exchange (ETDEWEB)

    Harding, G., E-mail: Geoffrey.Harding@Morphodetection.com [Morpho Detection Germany GmbH, Heselstuecken 3, 22453 Hamburg (Germany); Fleckenstein, H.; Kosciesza, D.; Olesinski, S.; Strecker, H.; Theedt, T.; Zienert, G. [Morpho Detection Germany GmbH, Heselstuecken 3, 22453 Hamburg (Germany)

    2012-07-15

    The steadily increasing number of explosive threat classes, including home-made explosives (HMEs), liquids, amorphous and gels (LAGs), is forcing up the false-alarm rates of security screening equipment. This development can best be countered by increasing the number of features available for classification. X-ray diffraction intrinsically offers multiple features for both solid and LAGs explosive detection, and is thus becoming increasingly important for false-alarm and cost reduction in both carry-on and checked baggage security screening. Following a brief introduction to X-ray diffraction imaging (XDI), which synthesizes in a single modality the image-forming and material-analysis capabilities of X-rays, the Multiple Inverse Fan Beam (MIFB) XDI topology is described. Physical relationships obtaining in such MIFB XDI components as the radiation source, collimators and room-temperature detectors are presented with experimental performances that have been achieved. Representative X-ray diffraction profiles of threat substances measured with a laboratory MIFB XDI system are displayed. The performance of Next-Generation (MIFB) XDI relative to that of the 2nd Generation XRD 3500{sup TM} screener (Morpho Detection Germany GmbH) is assessed. The potential of MIFB XDI, both for reducing the exorbitant cost of false alarms in hold baggage screening (HBS), as well as for combining 'in situ' liquid and solid explosive detection in carry-on luggage screening is outlined. - Highlights: Black-Right-Pointing-Pointer X-ray diffraction imaging (XDI) synthesizes analysis and imaging in one x-ray modality. Black-Right-Pointing-Pointer A novel XDI beam topology comprising multiple inverse fan-beams (MIFB) is described. Black-Right-Pointing-Pointer The MIFB topology is technically easy to realize and has high photon collection efficiency. Black-Right-Pointing-Pointer Applications are envisaged in checkpoint, hold baggage and cargo screening.

  2. A FOCUSED, HARD X-RAY LOOK AT ARP 299 WITH NuSTAR

    Energy Technology Data Exchange (ETDEWEB)

    Ptak, A.; Hornschemeier, A.; Lehmer, B.; Yukita, M.; Wik, D.; Tatum, M. [NASA Goddard Space Flight Center, Code 662, Greenbelt, MD 20771 (United States); Zezas, A. [Department of Physics, University of Crete, Herakleion (Greece); Antoniou, V. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Argo, M. K. [Jodrell Bank Centre for Astrophysics, The University of Manchester, Oxford Road, Manchester M13 9PL (United Kingdom); Ballo, L.; Della Ceca, R. [Osservatorio Astronomico di Brera (INAF), via Brera 28, I-20121 Milano (Italy); Bechtol, K. [Kavli Institute for Cosmological Physics, Chicago, IL 60637 (United States); Boggs, S.; Craig, W. W.; Krivonos, R. [U.C. Berkeley Space Sciences Laboratory, Berkeley, CA (United States); Christensen, F. E. [National Space Institute, Technical University of Denmark, DK-2100 Copenhagen (Denmark); Hailey, C. J. [Columbia University, New York, NY (United States); Harrison, F. A. [Caltech Division of Physics, Mathematics and Astronomy, Pasadena, CA (United States); Maccarone, T. J. [Department of Physics, Texas Tech University, Lubbock, TX 79409 (United States); Stern, D. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); and others

    2015-02-20

    We report on simultaneous observations of the local starburst system Arp 299 with NuSTAR and Chandra, which provides the first resolved images of this galaxy up to energies of ∼45 keV. Fitting the 3-40 keV spectrum reveals a column density of N {sub H} ∼ 4 × 10{sup 24} cm{sup –2}, characteristic of a Compton-thick active galactic nucleus (AGN), and a 10-30 keV luminosity of 1.2 × 10{sup 43} erg s{sup –1}. The hard X-rays detected by NuSTAR above 10 keV are centered on the western nucleus, Arp 299-B, which previous X-ray observations have shown to be the primary source of neutral Fe-K emission. Other X-ray sources, including Arp 299-A, the eastern nucleus also thought to harbor an AGN, as well as X-ray binaries, contribute ≲ 10% to the 10-20 keV emission from the Arp 299 system. The lack of significant emission above 10 keV other than that attributed to Arp 299-B suggests that: (1) any AGN in Arp 299-A must be heavily obscured (N {sub H} > 10{sup 24} cm{sup –2}) or have a much lower luminosity than Arp 299-B and (2) the extranuclear X-ray binaries have spectra that cut-off above ∼10 keV. Such soft spectra are characteristic of ultraluminous X-ray sources observed to date by NuSTAR.

  3. Performance Test of the Next Generation X-Ray Beam Position Monitor System for The APS Upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Yang, B.; Lee, S.; Westferro, F.; Jaski, Y.; Lenkszus, F.; Sereno, N.; Ramanathan, M.

    2017-03-25

    The Advanced Photon Source is developing its next major upgrade (APS-U) based on the multi-bend achromat lattice. Improved beam stability is critical for the upgrade and will require keeping short-time beam angle change below 0.25 µrad and long-term angle drift below 0.6 µrad. A reliable white x-ray beam diagnostic system in the front end will be a key part of the planned beam stabilization system. This system includes an x-ray beam position monitor (XBPM) based on x-ray fluorescence (XRF) from two specially designed GlidCop A-15 absorbers, a second XBPM using XRF photons from the Exit Mask, and two white beam intensity monitors using XRF from the photon shutter and Compton-scattered photons from the front end beryllium window or a retractable diamond film in windowless front ends. We present orbit stability data for the first XBPM used in the feedback control during user operations, as well as test data from the second XBPM and the intensity monitors. They demonstrate that the XBPM system meets APS-U beam stability requirements.

  4. Effect of inserted metal at anode tip on formation of pulsed X-ray emitting zone of plasma focus device

    Science.gov (United States)

    Miremad, Seyed Milad; Shirani Bidabadi, Babak

    2018-04-01

    The effect of the anode's insert material of a plasma focus device on the properties of X-ray emission zone was studied. Inserts were fabricated out of six different materials including aluminum, copper, zinc, tin, tungsten, and lead to cover a wide range of atomic numbers. For each anode's insert material at different gas pressures and different voltages, the shape of X-ray emission zone was recorded by three pinhole cameras, which were installed on sidewall and roof of the chamber of plasma focus device. The results indicated that by changing the gas pressure and the charge voltage of capacitor, the X-ray source of plasma focus emerges with different forms as a concentrated column or conical shape with sharp or cloudy edges. These structures are in the form of a combination of plasma emission and anode-tip emission with different intensities. These observations indicate that the material of the anode-tip especially affects the structure of X-ray emission zone.

  5. Proposal for electron beam induced remote sensing x-ray fluorescence investigation of minor bodies in the solar system

    International Nuclear Information System (INIS)

    Hrehuss, G.; Gombosi, T.I.; Naday, I.; Pogany, L.; Szegoe, K.

    1983-11-01

    The composition of the surface material of minor bodies in the solar system can be measured using a semiconductor soft x-ray spectrometer mounted on the space probe. The characteristic x-rays are excited by a 20 kV low current electron beam of a space-born electron gun. After the description of the main features of the technique, estimations on its sensitivity, supported by a model experiment, are given. The minimum fly-by distance to apply this method can be estimated as a few kilometers. (author)

  6. Reproducibility of temporomandibular joint tomography. Influence of shifted X-ray beam and tomographic focal plane on reproducibility

    International Nuclear Information System (INIS)

    Saito, Masashi

    1999-01-01

    Proper tomographic focal plane and x-ray beam direction are the most important factors to obtain accurate images of the temporomandibular joint (TMJ). In this study, to clarify the magnitude of effect of these two factors on the image quality. We evaluated the reproducibility of tomograms by measuring the distortion when the x-ray beam was shifted from the correct center of the object. The effects of the deviation of the tomographic focal plane on image quality were evaluated by the MTF (Modulation Transfer Function). Two types of tomograms, one the plane type, the other the rotational type were used in this study. A TMJ model was made from Teflon for the purpose of evaluation by shifting the x-ray beam. The x-ray images were obtained by tilting the model from 0 to 10 degrees 2-degree increments. These x-ray images were processed for computer image analysis, and then the distance between condyle and the joint space was measured. To evaluate the influence of the shifted tomographic focal plane on image sharpness, the x-ray images from each setting were analyzed by MTF. To obtain the MTF, ''knife-edge'' made from Pb was used. The images were scanned with a microdensitometer at the central focal plane, and 0, 0.5, 1 mm away respectively. The density curves were analyzed by Fourier analysis and the MTF was calculated. The reproducibility of images became worse by shifting the x-ray beam. This tendency was similar for both tomograms. Object characteristics such as anterior and posterior portion of the joint space affected the deterioration of reproducibility of the tomography. The deviation of the tomographic focal plane also decreased the reproducibility of the x-ray images. The rotational type showed a better MTF, but it became seriously unfavorable with slight changes of the tomographic focal plane. Contrarily, the plane type showed a lower MTF, but the image was stable with shifting of the tomographic focal plane. (author)

  7. Measurement of spectra for intra-oral X-ray beams using biological materials as attenuator

    International Nuclear Information System (INIS)

    Zenóbio, Madelon A.F.; Nogueira-Tavares, Maria S.; Zenóbio, Elton G.; Squair, Peterson Lima; Santos, Marcus A.P.; Silva, Teógenes A. da

    2011-01-01

    In diagnostic radiology, the radiation interaction probability in matter is a strong function of the X-ray energy. The knowledge of the X-ray energy spectral distribution allows optimizing the radiographic imaging system in order to obtain high quality images with as low as reasonably achievable patient doses. In this study, transmitted X-ray spectra through dentin and enamel that are existing materials in intra-oral radiology were experimentally determined in an X-ray equipment with 40–70 kV variable range. Dentin and enamel samples with 0.4–3.8 and 0.6–2.6 mm thick were used as attenuators. X-ray transmitted spectra were measured with XR-100T model CdTe detector and half-value layers (HVL) were determined. Characteristics of both dentin and enamel transmitted spectra showed that they have differences in the penetration power in matter and in the spectrum distribution. The results will be useful for phantom developments based on dentin and enamel for image quality control in dental radiology. - Highlights: ► The X-ray energy spectral distribution, optimize the radiographic imaging system. Transmitted X-ray spectra through dentin and enamel were experimentally determined. X-ray transmitted spectra were measured (XR-100T model CdTe detector). The transmitted spectra showed differences in the penetration power and spectrum distribution. Dentin and enamel transmitted spectra will be useful for phantom developments.

  8. A simulation-based study on the influence of beam hardening in X-ray computed tomography for dimensional metrology.

    Science.gov (United States)

    Lifton, Joseph J; Malcolm, Andrew A; McBride, John W

    2015-01-01

    X-ray computed tomography (CT) is a radiographic scanning technique for visualising cross-sectional images of an object non-destructively. From these cross-sectional images it is possible to evaluate internal dimensional features of a workpiece which may otherwise be inaccessible to tactile and optical instruments. Beam hardening is a physical process that degrades the quality of CT images and has previously been suggested to influence dimensional measurements. Using a validated simulation tool, the influence of spectrum pre-filtration and beam hardening correction are evaluated for internal and external dimensional measurements. Beam hardening is shown to influence internal and external dimensions in opposition, and to have a greater influence on outer dimensions compared to inner dimensions. The results suggest the combination of spectrum pre-filtration and a local gradient-based surface determination method are able to greatly reduce the influence of beam hardening in X-ray CT for dimensional metrology.

  9. Differential X-ray phase-contrast imaging with a grating interferometer using a laboratory X-ray micro-focus tube

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Kwon-Ha; Ryu, Jong-Hyun; Jung, Chang-Won [Wonkwang University School of Medicine, Iksan (Korea, Republic of); Ryu, Cheol-Woo; Kim, Young-Jo; Kwon, Young-Man [Jeonbuk Technopark, Iksan (Korea, Republic of); Park, Mi-Ran; Cho, Seung-Ryong [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Chon, Kwon-Su [Catholic University of Daegu, Gyeongsan (Korea, Republic of)

    2014-12-15

    X-ray phase-contrast imaging can provide images with much greater soft-tissue contrast than conventional absorption-based images. In this paper, we describe differential X-ray phase-contrast images of insect specimens that were obtained using a grating-based Talbot interferometer and a laboratory X-ray source with a spot size of a few tens of micrometers. We developed the interferometer on the basis of the wavelength, periods, and height of the gratings; the field of view depends on the size of the grating, considering the refractive index of the specimen. The phase-contrast images were acquired using phase-stepping methods. The phase contrast imaging provided a significantly enhanced soft-tissue contrast compared with the attenuation data. The contour of the sample was clearly visible because the refraction from the edges of the object was strong in the differential phase-contrast image. Our results demonstrate that a grating-based Talbot interferometer with a conventional X-ray tube may be attractive as an X-ray imaging system for generating phase images. X-ray phase imaging obviously has sufficient potential and is expected to soon be a great tool for medical diagnostics.

  10. Differential X-ray phase-contrast imaging with a grating interferometer using a laboratory X-ray micro-focus tube

    International Nuclear Information System (INIS)

    Yoon, Kwon-Ha; Ryu, Jong-Hyun; Jung, Chang-Won; Ryu, Cheol-Woo; Kim, Young-Jo; Kwon, Young-Man; Park, Mi-Ran; Cho, Seung-Ryong; Chon, Kwon-Su

    2014-01-01

    X-ray phase-contrast imaging can provide images with much greater soft-tissue contrast than conventional absorption-based images. In this paper, we describe differential X-ray phase-contrast images of insect specimens that were obtained using a grating-based Talbot interferometer and a laboratory X-ray source with a spot size of a few tens of micrometers. We developed the interferometer on the basis of the wavelength, periods, and height of the gratings; the field of view depends on the size of the grating, considering the refractive index of the specimen. The phase-contrast images were acquired using phase-stepping methods. The phase contrast imaging provided a significantly enhanced soft-tissue contrast compared with the attenuation data. The contour of the sample was clearly visible because the refraction from the edges of the object was strong in the differential phase-contrast image. Our results demonstrate that a grating-based Talbot interferometer with a conventional X-ray tube may be attractive as an X-ray imaging system for generating phase images. X-ray phase imaging obviously has sufficient potential and is expected to soon be a great tool for medical diagnostics

  11. X-ray beam-shaping via deformable mirrors: surface profile and point spread function computation for Gaussian beams using physical optics.

    Science.gov (United States)

    Spiga, D

    2018-01-01

    X-ray mirrors with high focusing performances are commonly used in different sectors of science, such as X-ray astronomy, medical imaging and synchrotron/free-electron laser beamlines. While deformations of the mirror profile may cause degradation of the focus sharpness, a deliberate deformation of the mirror can be made to endow the focus with a desired size and distribution, via piezo actuators. The resulting profile can be characterized with suitable metrology tools and correlated with the expected optical quality via a wavefront propagation code or, sometimes, predicted using geometric optics. In the latter case and for the special class of profile deformations with monotonically increasing derivative, i.e. concave upwards, the point spread function (PSF) can even be predicted analytically. Moreover, under these assumptions, the relation can also be reversed: from the desired PSF the required profile deformation can be computed analytically, avoiding the use of trial-and-error search codes. However, the computation has been so far limited to geometric optics, which entailed some limitations: for example, mirror diffraction effects and the size of the coherent X-ray source were not considered. In this paper, the beam-shaping formalism in the framework of physical optics is reviewed, in the limit of small light wavelengths and in the case of Gaussian intensity wavefronts. Some examples of shaped profiles are also shown, aiming at turning a Gaussian intensity distribution into a top-hat one, and checks of the shaping performances computing the at-wavelength PSF by means of the WISE code are made.

  12. Evaluation of secondary electron filter for removing contaminant electrons from high-energy 6 MV x-ray beam

    International Nuclear Information System (INIS)

    Kumagai, Kozo

    1988-01-01

    When using high energy X-rays, the dose increases at the skin surface and build-up region of beam contamination of secondary electrons coming out from the inner surface of the lineac head. At our radiotherapy department, many cases of external otitis from severe skin reactions, particularly resulting from whole brain irradiation of primary and metastatic brain tumors with a 6 MV X-ray lineac, have been encountered. An investigation was made of the physical aspects of a 6 MV X-ray beam using three electron filters, lead lucite, lead glass and lucite to remove secondary electrons. Transparent materials for filters should be preferable for locating the light field. The following results were obtained: 1) For removing secondary electrons, a lead lucite filter was found best. 2) The lead lucite filter proved most effective for removing secondary electrons from the area of treatment. It reduced the dose of irradiation to the skin surface and build-up region, and furthermore improved the depth dose relative to that without filters. 3) From a clinical standpoint, skin reactions such as external otitis remarkably decreased using a lead lucite filter. 4) It thus appears necessary to use a high energy X-ray with newly designed filters to reduce beam contamination of secondary electrons. (author)

  13. Measurement of high energy x-ray beam penumbra with Gafchromic trade mark sign EBT radiochromic film

    International Nuclear Information System (INIS)

    Cheung Tsang; Butson, Martin J.; Yu, Peter K. N.

    2006-01-01

    High energy x-ray beam penumbra are measured using Gafchromic trade mark sign EBT film. Gafchromic trade mark sign EBT, due to its limited energy dependence and high spatial resolution provide a high level of accuracy for dose assessment in penumbral regions. The spatial resolution of film detector systems is normally limited by the scanning resolution of the densitometer. Penumbral widths (80%/20%) measured at D max were found to be 2.8, 3.0, 3.2, and 3.4 mm (±0.2 mm) using 5, 10, 20, and 30 cm square field sizes, respectively, for a 6 MV linear accelerator produced x-ray beam. This is compared to 3.2 mm±0.2 mm (Kodak EDR2) and 3.6 mm±0.2 mm (Kodak X-Omat V) at 10 cmx10 cm measured using radiographic film. Using a zero volume extrapolation technique for ionization chamber measurements, the 10 cmx10 cm field penumbra at D max was measured to be 3.1 mm, a close match to Gafchromic trade mark sign EBT results. Penumbral measurements can also be made at other depths, including the surface, as the film does not suffer significantly from dosimetric variations caused by changing x-ray energy spectra. Gafchromic trade mark sign EBT film provides an adequate measure of penumbral dose for high energy x-ray beams

  14. Transport Measurements and Synchrotron-Based X-Ray Absorption Spectroscopy of Iron Silicon Germanide Grown by Molecular Beam Epitaxy

    Science.gov (United States)

    Elmarhoumi, Nader; Cottier, Ryan; Merchan, Greg; Roy, Amitava; Lohn, Chris; Geisler, Heike; Ventrice, Carl, Jr.; Golding, Terry

    2009-03-01

    Some of the iron-based metal silicide and germanide phases have been predicted to be direct band gap semiconductors. Therefore, they show promise for use as optoelectronic materials. We have used synchrotron-based x-ray absorption spectroscopy to study the structure of iron silicon germanide films grown by molecular beam epitaxy. A series of Fe(Si1-xGex)2 thin films (2000 -- 8000å) with a nominal Ge concentration of up to x = 0.04 have been grown. X-ray absorption near edge structure (XANES) and extended x-ray absorption fine structure (EXAFS) measurements have been performed on the films. The nearest neighbor co-ordination corresponding to the β-FeSi2 phase of iron silicide provides the best fit with the EXAFS data. Temperature dependent (20 coefficient was calculated. Results suggest semiconducting behavior of the films which is consistent with the EXAFS results.

  15. Soft X-ray generation in gases by means of a pulsed electron beam produced in a high-voltage barier discharge

    NARCIS (Netherlands)

    Azarov, A.V.; Peters, P.J.M.; Boller, Klaus J.

    2007-01-01

    A large area pulsed electron beam is produced by a high-voltage barrier discharge. We compare the properties of the x-rays generated by stopping this beam of electrons in a thin metal foil with those generated by stopping the electrons directly in various gases. The generation of x-rays was

  16. Study of salinity in aqueous medium using X-Ray beam with MCNP-X code

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa, Caroline M.; Braz, Delson [Coordenacao de Pos-Graduacao e Pesquisa de Engenharia (PEN/COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear; Salgado, César M., E-mail: cbarbosa@nuclear.ufrj.br, E-mail: delson@nuclear.ufrj.br, E-mail: otero@ien.gov.br [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2017-07-01

    In offshore production, it is possible that the produced water presents geochemical characteristics that correspond to the mixture of formation water (connate water) and the sea water (injection water), and the physical-chemical behavior of the injected water allows a considerable variation in the index of salinity altering the water/oil ratio during transportation and/or extraction. Injection water is generally used to raise the reservoir pressure, increasing the percentage of extracted oil. This water has a significant amount of salts that generate some difficulties, such as measuring fractions of volume in multiphase systems. One way to check the effects of salinity would be to regularly measure the amount of salt present in the water. In this way, this work presents a methodology to measure the concentration and the types of salts using nuclear techniques through the MCNP-X computational code. The measurement geometry uses an X-ray beam (40-100 keV) and NaI(Tl) scintillation detector positioned diametrically opposed to the source. The studied samples were the NaCl, KCl and MgCl{sub 2} salts in aqueous solution. The results present the possibility of differentiating the formation and injection waters due to differences in the salt concentrations. (author)

  17. Applications of pixellated GaAs X-ray detectors in a synchrotron radiation beam

    CERN Document Server

    Watt, J; Campbell, M; Mathieson, K; Mikulec, B; O'Shea, V; Passmore, M S; Schwarz, C; Smith, K M; Whitehill, C

    2001-01-01

    Hybrid semiconductor pixel detectors are being investigated as imaging devices for radiography and synchrotron radiation beam applications. Based on previous work in the CERN RD19 and the UK IMPACT collaborations, a photon counting GaAs pixel detector (PCD) has been used in an X-ray powder diffraction experiment. The device consists of a 200 mu m thick SI-LEC GaAs detector patterned in a 64*64 array of 170 mu m pitch square pixels, bump-bonded to readout electronics operating in single photon counting mode. Intensity peaks in the powder diffraction pattern of KNbO/sub 3/ have been resolved and compared with results using the standard scintillator, and a PCD predecessor (the Omega 3). The PCD shows improved speed, dynamic range, 2-D information and comparable spatial resolution to the standard scintillator based systems. It also overcomes the severe dead time limitations of the Omega 3 by using a shutter based acquisition mode. A brief demonstration of the possibilities of the system for dental radiography and...

  18. Study of energy dependence of a extrapolation chamber in low energy X-rays beams

    International Nuclear Information System (INIS)

    Bastos, Fernanda M.; Silva, Teogenes A. da

    2014-01-01

    This work was with the main objective to study the energy dependence of extrapolation chamber in low energy X-rays to determine the value of the uncertainty associated with the variation of the incident radiation energy in the measures in which it is used. For studying the dependence of energy, were conducted comparative ionization current measurements between the extrapolation chamber and two ionization chambers: a chamber mammography, RC6M model, Radcal with energy dependence less than 5% and a 2575 model radioprotection chamber NE Technology; both chambers have very thin windows, allowing its application in low power beams. Measurements were made at four different depths of 1.0 to 4.0 mm extrapolation chamber, 1.0 mm interval, for each reference radiation. The study showed that there is a variable energy dependence on the volume of the extrapolation chamber. In other analysis, it is concluded that the energy dependence of extrapolation chamber becomes smaller when using the slope of the ionization current versus depth for the different radiation reference; this shows that the extrapolation technique, used for the absorbed dose calculation, reduces the uncertainty associated with the influence of the response variation with energy radiation

  19. Specific features of two diffraction schemes for a widely divergent X-ray beam

    Energy Technology Data Exchange (ETDEWEB)

    Avetyan, K. T.; Levonyan, L. V.; Semerjian, H. S.; Arakelyan, M. M., E-mail: marakelyan@ysu.am; Badalyan, O. M. [Yerevan State University (Armenia)

    2015-03-15

    We investigated the specific features of two diffraction schemes for a widely divergent X-ray beam that use a circular diaphragm 30–50 μm in diameter as a point source of characteristic radiation. In one of the schemes, the diaphragm was set in front of the crystal (the diaphragm-crystal (d-c) scheme); in the other, it was installed behind the crystal (the crystal-diaphragm (c-d) scheme). It was established that the diffraction image in the c-d scheme is a topographic map of the investigated crystal area. In the d-c scheme at L = 2l (l and L are the distances between the crystal and the diaphragm and between the photographic plate and the diaphragm, respectively), the branches of hyperbolas formed in this family of planes (hkl) by the characteristic K{sub α} and K{sub β} radiations, including higher order reflections, converge into one straight line. It is experimentally demonstrated that this convergence is very sensitive to structural inhomogeneities in the crystal under study.

  20. Radiation shielding analysis of a special linear accelerator for electron beam and X-ray.

    Science.gov (United States)

    Kang, W G; Pyo, S H; Alkhuraiji, T S; Han, B S; Kang, C M

    2017-01-01

    The King AbdulAziz City for Science & Technology in the Kingdom of Saudi Arabia plans to build a 10 MeV, 15 kW linear accelerator (LINAC) for electron beam and X-ray. The accelerator will be supplied by EB Tech, Republic of Korea, and the design and construction of the accelerator building will be conducted in the cooperation with EB Tech. This report presents the shielding analysis of the accelerator building using the Monte Carlo N-Particle Transport Code (MCNP). In order to improve the accuracy in estimating deep radiation penetration and to reduce computation time, various variance reduction techniques, including the weight window (WW) method, the deterministic transport (DXTRAN) spheres were considered. Radiation levels were estimated at selected locations in the shielding facility running MCNP6 for particle histories up to 1.0×10+8. The final results indicated that the calculated doses at all selected detector locations met the dose requirement of 50 mSv/yr, which is the United State Nuclear Regulatory Commission (U.S. NRC) requirement.

  1. Photoneutron intensity variation with field size around radiotherapy linear accelerator 18-MeV X-ray beam

    Energy Technology Data Exchange (ETDEWEB)

    Al-Ghamdi, H.; Fazal-ur-Rehman [Physics Department, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Al-Jarallah, M.I. [Physics Department, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia)], E-mail: mibrahim@kfupm.edu.sa; Maalej, N. [Physics Department, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia)

    2008-08-15

    In X-ray radiotherapy accelerators, neutrons are produced mainly by ({gamma},n) reaction when high energy X-rays interact with high Z materials of the linear accelerator head. These materials include the lead (Pb) used as shielding in the collimator, tungsten (W) target used for the production of X-rays and iron (Fe) in the accelerator head. These unwanted neutrons contaminate the therapeutic beam and contribute to the patient dose during the treatment of a cancer patient. Knowing the neutron distribution around the radiotherapy accelerator is therefore desired. CR-39 nuclear track detectors (NTDs) were used to study the variation of fast and thermal neutron relative intensities around an 18 MeV linear accelerator X-ray beam with the field sizes of 0, 10x10, 20x20, 30x30 and 40x40cm{sup 2}. For fast neutron detection, bare NTDs were used. For thermal neutron detection, NTDs were covered with lithium tetra borate (Li{sub 2}B{sub 4}O{sub 7}) converters. The NTDs were placed at different locations in the direction perpendicular to the treatment couch (transversal) and in the direction parallel to the treatment couch (longitudinal) with respect to the isocenter of the accelerator. The fast neutron relative intensity is symmetrical about the beam axis and exhibits an exponential-like drop with distance from the isocenter of the accelerator for all the field sizes. At the primary beam (isocenter), the relative fast neutron intensity is highest for 40x40cm{sup 2} field size and decreases linearly with the decrease in the field size. However, fast neutron intensities do not change significantly with beam size for the measurements outside the primary beam. The fast neutron intensity in the longitudinal direction outside the primary beam decreases linearly with the field size. The thermal neutron intensity, at any location, was found to be almost independent of the field size.

  2. Impact of polychromatic x-ray sources on helical, cone-beam computed tomography and dual-energy methods

    International Nuclear Information System (INIS)

    Sidky, Emil Y; Zou Yu; Pan Xiaochuan

    2004-01-01

    Recently, there has been much work devoted to developing accurate and efficient algorithms for image reconstruction in helical, cone-beam computed tomography (CT). Little attention, however, has been directed to the effect of physical factors on helical, cone-beam CT image reconstruction. This work investigates the effect of polychromatic x-rays on image reconstruction in helical, cone-beam computed tomography. A pre-reconstruction dual-energy technique is developed to reduce beam-hardening artefacts and enhance contrast in soft tissue

  3. X-Ray Absorption with Transmission X-Ray Microscopes

    NARCIS (Netherlands)

    de Groot, F.M.F.

    2016-01-01

    In this section we focus on the use of transmission X-ray microscopy (TXM) to measure the XAS spectra. In the last decade a range of soft X-ray and hard X-ray TXM microscopes have been developed, allowing the measurement of XAS spectra with 10–100 nm resolution. In the hard X-ray range the TXM

  4. Time resolved, 2-D hard X-ray imaging of relativistic electron-beam target interactions on ETA-II

    International Nuclear Information System (INIS)

    Crist, C.E.; Sampayan, S.; Westenskow, G.; Caporaso, G.; Houck, T.; Weir, J.; Trimble, D.; Krogh, M.

    1998-01-01

    Advanced radiographic applications require a constant source size less than 1 mm. To study the time history of a relativistic electron beam as it interacts with a bremsstrahlung converter, one of the diagnostics they use is a multi-frame time-resolved hard x-ray camera. They are performing experiments on the ETA-II accelerator at Lawrence Livermore National Laboratory to investigate details of the electron beam/converter interactions. The camera they are using contains 6 time-resolved images, each image is a 5 ns frame. By starting each successive frame 10 ns after the previous frame, they create a 6-frame movie from the hard x-rays produced from the interaction of the 50-ns electron beam pulse

  5. SU-D-209-02: Percent Depth Dose Curves for Fluoroscopic X-Ray Beam Qualities Incorporating Copper Filtration

    Energy Technology Data Exchange (ETDEWEB)

    Wunderle, K [Cleveland Clinic Foundation, Cleveland, OH (United States); Wayne State University School of Medicine, Detroit, MI (United States); Godley, A; Shen, Z; Dong, F [Cleveland Clinic Foundation, Cleveland, OH (United States); Rakowski, J [Wayne State University School of Medicine, Detroit, MI (United States)

    2016-06-15

    Purpose: The purpose of this investigation was to quantify percent depth dose (PDD) curves for fluoroscopic x-ray beam qualities incorporating added copper filtration. Methods: A PTW (Freiburg, Germany) MP3 water tank was used with a Standard Imaging (Middleton, WI) Exradin Model 11 Spokas Chamber to measure PDD curves for 60, 80, 100 and 120 kVp x-ray beams with copper filtration ranging from 0.0–0.9 mm at 22cm and 42cm fields of view from 0 to 150 mm of water. A free-in-air monitor chamber was used to normalize the water tank data to fluctuations in output from the fluoroscope. The measurements were acquired on a Siemens (Erlangen, Germany) Artis ZeeGo fluoroscope. The fluoroscope was inverted from the typical orientation providing an x-ray beam originating from above the water tank. The water tank was positioned so that the water level was located at 60cm from the focal spot; which also represents the focal spot to interventional reference plane distance for that fluoroscope. Results: PDDs for 60, 80, 100, and 120 kVp with 0 mm of copper filtration compared well to previously published data by Fetterly et al. [Med Phys, 28, 205 (2001)] for those beam qualities given differences in fluoroscopes, geometric orientation, type of ionization chamber, and the water tank used for data collection. PDDs for 60, 80, 100, and 120 kVp with copper filtration were obtained and are presented, which have not been previously investigated and published. Conclusion: The equipment and processes used to acquire the reported data were sound and compared well with previously published data for PDDs without copper filtration. PDD data for the fluoroscopic x-ray beams incorporating copper filtration can be used as reference data for estimating organ or soft tissue dose at depth involving similar beam qualities or for comparison with mathematical models.

  6. X-Ray Beam Studies of Charge Sharing in Small Pixel, Spectroscopic, CdZnTe Detectors

    Science.gov (United States)

    Allwork, Christopher; Kitou, Dimitris; Chaudhuri, Sandeep; Sellin, Paul J.; Seller, Paul; Veale, Matthew C.; Tartoni, Nicola; Veeramani, Perumal

    2012-08-01

    Recent advances in the growth of CdZnTe material have allowed the development of small pixel, spectroscopic, X-ray imaging detectors. These detectors have applications in a diverse range of fields such as medical, security and industrial sectors. As the size of the pixels decreases relative to the detector thickness, the probability that charge is shared between multiple pixels increases due to the non zero width of the charge clouds drifting through the detector. These charge sharing events will result in a degradation of the spectroscopic performance of detectors and must be considered when analyzing the detector response. In this paper charge sharing and charge loss in a 250 μm pitch CdZnTe pixel detector has been investigated using a mono-chromatic X-ray beam at the Diamond Light Source, U.K. Using a 20 μm beam diameter the detector response has been mapped for X-ray energies both above (40 keV) and below (26 keV) the material K-shell absorption energies to study charge sharing and the role of fluorescence X-rays in these events.

  7. Measure of the attenuation curve of a beam of X-rays with TLD-100 dosimeters of LiF

    International Nuclear Information System (INIS)

    Bonzi, E. V.; Mainardi, R. T.; Germanier, A.; Delgado, V.

    2011-10-01

    The attenuation curve of a beam of X-rays represents the beam intensity in function of the attenuator thickness interposed between the source and the detector. To know with the major possible precision the attenuation curve is indispensable in procedures of spectral reconstruction. Their periodic measuring also offers valuable information on the correct operation of a tube of X-rays, diagnostic or therapy, when not have a specific detector for that activity. In this work was measured the attenuation curve of a tube of X-rays operated to 50 kV and 0.5 ma, using existent elements in any diagnostic or therapy laboratory with radiations. In the measures commercial aluminum foil was used, bent until 24 times and thermoluminescent dosimeters TLD 100 - LiF. Also, for comparison, was measured this attenuation curve with an ionization chamber brand Capintec model 192. Was determined by X-rays fluorescence the composition of the aluminium foil, since the present elements in the alloy can to affect the form of the attenuation curve. It is interesting to observe that these elements are in very low proportion (ppm) that they do not alter the attenuation capacity of the pure aluminium. Finally in a precision balance we weigh a big piece (30 cm x 100 cm) of aluminium foil and we obtained the thickness in g/c m2. It is possible to obtain attenuation curves of a beam of X-rays, with a high precision procedure and reproducibility. The use of TLD-100 dosimeters of LiF or similar makes that this activity was also quick and simple. (Author)

  8. Development of an x-ray beam line at the NSLS for studies in materials science using x-ray absorption spectroscopy

    International Nuclear Information System (INIS)

    Sayers, D.E.

    1989-01-01

    At the time of the submission of the original proposal more than 7 years ago, the X-11 PRT had set as a goal to develop one of the leading and most comprehensive x-ray absorption beam lines in the world. By any measure we have been successful. As is well documented in previous annual progress report and in the NSLS annual reports, our PRT has been extremely productive in a wide range of topics in materials science, solid state physics, chemistry and biology. Well over 100 papers have been published acknowledging the support of this contract and this continues at a rate of about 30 papers per year and about 20 invited presentations per year. Significant in this report are major studies in high T c compounds, advances in interface studies, new results in premelting phenomena, several pioneering studies in application of XAS to electrochemistry and significant progress in our understanding of the structure of amorphous chalcogenide systems and their photostructural changes

  9. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... evaluation. National and international radiology protection organizations continually review and update the technique standards used by radiology professionals. Modern x-ray systems have very controlled x-ray beams and dose ...

  10. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... changes seen in metabolic conditions. assist in the detection and diagnosis of bone cancer . locate foreign objects ... standards used by radiology professionals. Modern x-ray systems have very controlled x-ray beams and dose ...

  11. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... standards used by radiology professionals. Modern x-ray systems have very controlled x-ray beams and dose control methods to minimize stray (scatter) radiation. This ensures that ...

  12. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... current x-ray images for diagnosis and disease management. top of page How is the procedure performed? ... have very controlled x-ray beams and dose control methods to minimize stray (scatter) radiation. This ensures ...

  13. Two-dimensional x-ray magnification based on a monolithic beam conditioner

    Czech Academy of Sciences Publication Activity Database

    Korytár, D.; Mikulík, P.; Ferrari, C.; Hrdý, Jaromír; Baumbach, T.; Freund, A.; Kuběna, A.

    2003-01-01

    Roč. 36, - (2003), s. 1-4 ISSN 0022-3727 R&D Projects: GA AV ČR IAA1010104; GA MŠk OC P7.001 Institutional research plan: CEZ:AV0Z1010914 Keywords : x-ray crystal diffraction * x-ray magnifier Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.265, year: 2003

  14. Analyzer-based phase-contrast imaging system using a micro focus x-ray source

    International Nuclear Information System (INIS)

    Zhou, Wei; Majidi, Keivan; Brankov, Jovan G.

    2014-01-01

    Here we describe a new in-laboratory analyzer based phase contrast-imaging (ABI) instrument using a conventional X-ray tube source (CXS) aimed at bio-medical imaging applications. Phase contrast-imaging allows visualization of soft tissue details usually obscured in conventional X-ray imaging. The ABI system design and major features are described in detail. The key advantage of the presented system, over the few existing CXS ABI systems, is that it does not require high precision components, i.e., CXS, X-ray detector, and electro-mechanical components. To overcome a main problem introduced by these components, identified as temperature stability, the system components are kept at a constant temperature inside of three enclosures, thus minimizing the electrical and mechanical thermal drifts. This is achieved by using thermoelectric (Peltier) cooling/heating modules that are easy to control precisely. For CXS we utilized a microfocus X-ray source with tungsten (W) anode material. In addition the proposed system eliminates tungsten's multiple spectral lines by selecting monochromator crystal size appropriately therefore eliminating need for the costly mismatched, two-crystal monochromator. The system imaging was fine-tuned for tungsten Kα 1 line with the energy of 59.3 keV since it has been shown to be of great clinical significance by a number of researchers at synchrotron facilities. In this way a laboratory system that can be used for evaluating and quantifying tissue properties, initially explored at synchrotron facilities, would be of great interest to a larger research community. To demonstrate the imaging capability of our instrument we use a chicken thigh tissue sample

  15. Analyzer-based phase-contrast imaging system using a micro focus x-ray source

    Science.gov (United States)

    Zhou, Wei; Majidi, Keivan; Brankov, Jovan G.

    2014-08-01

    Here we describe a new in-laboratory analyzer based phase contrast-imaging (ABI) instrument using a conventional X-ray tube source (CXS) aimed at bio-medical imaging applications. Phase contrast-imaging allows visualization of soft tissue details usually obscured in conventional X-ray imaging. The ABI system design and major features are described in detail. The key advantage of the presented system, over the few existing CXS ABI systems, is that it does not require high precision components, i.e., CXS, X-ray detector, and electro-mechanical components. To overcome a main problem introduced by these components, identified as temperature stability, the system components are kept at a constant temperature inside of three enclosures, thus minimizing the electrical and mechanical thermal drifts. This is achieved by using thermoelectric (Peltier) cooling/heating modules that are easy to control precisely. For CXS we utilized a microfocus X-ray source with tungsten (W) anode material. In addition the proposed system eliminates tungsten's multiple spectral lines by selecting monochromator crystal size appropriately therefore eliminating need for the costly mismatched, two-crystal monochromator. The system imaging was fine-tuned for tungsten Kα1 line with the energy of 59.3 keV since it has been shown to be of great clinical significance by a number of researchers at synchrotron facilities. In this way a laboratory system that can be used for evaluating and quantifying tissue properties, initially explored at synchrotron facilities, would be of great interest to a larger research community. To demonstrate the imaging capability of our instrument we use a chicken thigh tissue sample.

  16. Analyzer-based phase-contrast imaging system using a micro focus x-ray source

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Wei [BME Department, Illinois Institute of Technology, Chicago, Illinois 60616 (United States); Majidi, Keivan; Brankov, Jovan G., E-mail: brankov@iit.edu [ECE Department, Illinois Institute of Technology, Chicago, Illinois 60616 (United States)

    2014-08-15

    Here we describe a new in-laboratory analyzer based phase contrast-imaging (ABI) instrument using a conventional X-ray tube source (CXS) aimed at bio-medical imaging applications. Phase contrast-imaging allows visualization of soft tissue details usually obscured in conventional X-ray imaging. The ABI system design and major features are described in detail. The key advantage of the presented system, over the few existing CXS ABI systems, is that it does not require high precision components, i.e., CXS, X-ray detector, and electro-mechanical components. To overcome a main problem introduced by these components, identified as temperature stability, the system components are kept at a constant temperature inside of three enclosures, thus minimizing the electrical and mechanical thermal drifts. This is achieved by using thermoelectric (Peltier) cooling/heating modules that are easy to control precisely. For CXS we utilized a microfocus X-ray source with tungsten (W) anode material. In addition the proposed system eliminates tungsten's multiple spectral lines by selecting monochromator crystal size appropriately therefore eliminating need for the costly mismatched, two-crystal monochromator. The system imaging was fine-tuned for tungsten Kα{sub 1} line with the energy of 59.3 keV since it has been shown to be of great clinical significance by a number of researchers at synchrotron facilities. In this way a laboratory system that can be used for evaluating and quantifying tissue properties, initially explored at synchrotron facilities, would be of great interest to a larger research community. To demonstrate the imaging capability of our instrument we use a chicken thigh tissue sample.

  17. Physics Of, and Science With, the X-Ray Free-Electron Laser: 19th Advanced ICFA Beam Dynamics Workshop

    International Nuclear Information System (INIS)

    Sutton, M.

    2003-01-01

    The workshop brought together scientists working on the development of x-ray free-electron lasers, and its applications. X-ray free-electron lasers produce high intensity, subpicosecond long, coherent, X-ray pulses, and will open a new frontier to study the structure of matter at the molecular and atomic levels. Some fields of interest are structural changes in chemical reactions, single biological molecule, warm plasmas, nanosystems. Summary of discussions and conclusions of Group 1: Physics and Technology of the XFEL - The main issues that were discussed by the 50 participants in this group were the photo-injector, the production of ultra-short pulses, the effects of wake-fields induced by the electron bunch, the operation at lower charge and emittance, the possibility of harmonic generation and the diagnostics in the undulator. The following is a short summary of the discussions and their conclusions. Summary of discussions and conclusions of Group 2: Science with the XFEL - About 25 people attended sessions to discuss the possible scientific applications of a x-ray FEL. Because of the recent focus on the first experiments with the proposed Linac Coherent Light Source at Stanford, the discussions were mainly focussed on these proposals. The extension of the characteristics beyond the initial stage and the further developments of the source were also part of the program. Six scientific areas were discussed: Atomic Physics, Warm Dense Matter, Femtosecond Chemistry, Imaging/Holography, Bio-molecular Structures and X-Ray Fluctuations Spectroscopy.

  18. Research on pinches driven by Speed-2 generator: Hard X-ray and neutron emission in plasma focus configuration

    Energy Technology Data Exchange (ETDEWEB)

    Soto, L.; Moreno, J.; Silva, P.; Sylvester, G.; Zambra, M.; Pavez, C. [Comision Chilena de Energia Nuclear, Santiago (Chile); Pavez, C. [Universidad de Concepcion (Chile); Raspa, V. [Buenos Aires Univ., PLADEMA, CONICET and INFIP (Argentina); Castillo, F. [Insitituto de Ciencias Nucleares, UNAM (Mexico); Kies, W. [Heinrich-Heine-Univ., Dusseldorf (Germany)

    2004-07-01

    Speed-2 is a generator based on Marx technology and was designed in the University of Dusseldorf. Speed-2 consists on 40 +/- Marx modules connected in parallel (4.1 {mu}F equivalent Marx generator capacity, 300 kV, 4 MA in short circuit, 187 kJ, 400 ns rise time, dI/dt {approx} 10{sup 13} A/s). Currently Speed-2 is operating at CCHEN (Chilean nuclear energy commission), being the most powerful and energetic device for dense transient plasma in the Southern Hemisphere. Most of the previous works developed in Speed-2 at Dusseldorf were done in a plasma focus configuration for soft X-ray emission and the neutron emission from Speed-2 was not completely studied. The research program at CCHEN considers experiments in different pinch configurations (plasma focus, gas puffed plasma focus, gas embedded Z-pinch, wire arrays) at current of hundred of kilo- to mega-amperes, using the Speed-2 generator. The Chilean operation has begun implementing and developing diagnostics in a conventional plasma focus configuration operating in deuterium in order to characterize the neutron emission and the hard X-ray production. Silver activation counters, plastics CR39 and scintillator-photomultiplier detectors are used to characterize the neutron emission. Images of metallic plates with different thickness are obtained on commercial radiographic film, Agfa Curix ST-G2, in order to characterize an effective energy of the hard X-ray outside of the discharge. (authors)

  19. Mechanical design of multiple zone plates precision alignment apparatus for hard X-ray focusing in twenty-nanometer scale

    Energy Technology Data Exchange (ETDEWEB)

    Shu, Deming; Liu, Jie; Gleber, Sophie C.; Vila-Comamala, Joan; Lai, Barry; Maser, Jorg M.; Roehrig, Christian; Wojcik, Michael J.; Vogt, Franz Stefan

    2017-04-04

    An enhanced mechanical design of multiple zone plates precision alignment apparatus for hard x-ray focusing in a twenty-nanometer scale is provided. The precision alignment apparatus includes a zone plate alignment base frame; a plurality of zone plates; and a plurality of zone plate holders, each said zone plate holder for mounting and aligning a respective zone plate for hard x-ray focusing. At least one respective positioning stage drives and positions each respective zone plate holder. Each respective positioning stage is mounted on the zone plate alignment base frame. A respective linkage component connects each respective positioning stage and the respective zone plate holder. The zone plate alignment base frame, each zone plate holder and each linkage component is formed of a selected material for providing thermal expansion stability and positioning stability for the precision alignment apparatus.

  20. Evaluation of mammographic X-ray beams using a phosphor plate

    Energy Technology Data Exchange (ETDEWEB)

    Bustos F, M.; Prata M, A., E-mail: mbustos@ufmg.br [Universidade Federal de Minas Gerais, Departamento de Engenharia Nuclear, Av. Pte. Antonio Carlos 6627, 31270-901 Pampulha, Belo Horizonte, Minas Gerais (Brazil)

    2016-10-15

    Currently, breast cancer is the second type of cancer more with higher overall incidence recorded in 2015, more than 57,000 new cases according to the National Cancer Institute of Brazil Mammography is now one of the imaging technique most widely used worldwide for the early diagnosis of breast cancer. The computed radiography (Cr) plates are used to obtain digital radiographs, and are widely used for digital mammogram production. This study aims to evaluate the variation response in the exposure of a Cr plate in mammography unit. For this study a mammography device model Graph A F Mammo, made by Vmi and a Cr plate, model Regius, were used for mammography. Experiments were made with two X-ray beams of 20 and 25 kV. Successive exposures of the Cr plate were made in a time range time from 0.5 to 2.5 s., to obtain unprocessed images .raw and subsequently make the measurement of time, air kerma and air kerma rate using a Ray Safe Xi meter. Five measurements for each exposure time were performed and the images were analyzed using the Image J software. A matrix of 21 x 21 pixels was selected in the central region of each image to obtain the intensity value, in grey scale, for each exposure time. From these data, a correlation of the degree of darkening was made with time and the air kerma. The behavior of the curves corresponding to the intensity average values of central pixels in relation to the exposure time and air kerma are similar for both voltages,showing an initially linear behavior and then a plate saturation region, whichever occurs first at the greatest value of the applied voltage. (Author)

  1. Evaluation of mammographic X-ray beams using a phosphor plate

    International Nuclear Information System (INIS)

    Bustos F, M.; Prata M, A.

    2016-10-01

    Currently, breast cancer is the second type of cancer more with higher overall incidence recorded in 2015, more than 57,000 new cases according to the National Cancer Institute of Brazil Mammography is now one of the imaging technique most widely used worldwide for the early diagnosis of breast cancer. The computed radiography (Cr) plates are used to obtain digital radiographs, and are widely used for digital mammogram production. This study aims to evaluate the variation response in the exposure of a Cr plate in mammography unit. For this study a mammography device model Graph A F Mammo, made by Vmi and a Cr plate, model Regius, were used for mammography. Experiments were made with two X-ray beams of 20 and 25 kV. Successive exposures of the Cr plate were made in a time range time from 0.5 to 2.5 s., to obtain unprocessed images .raw and subsequently make the measurement of time, air kerma and air kerma rate using a Ray Safe Xi meter. Five measurements for each exposure time were performed and the images were analyzed using the Image J software. A matrix of 21 x 21 pixels was selected in the central region of each image to obtain the intensity value, in grey scale, for each exposure time. From these data, a correlation of the degree of darkening was made with time and the air kerma. The behavior of the curves corresponding to the intensity average values of central pixels in relation to the exposure time and air kerma are similar for both voltages,showing an initially linear behavior and then a plate saturation region, whichever occurs first at the greatest value of the applied voltage. (Author)

  2. Dosimetry and monitoring of thin X-ray beam produced by linear particle accelerator, for application in radiography

    International Nuclear Information System (INIS)

    Campos, J.C.F. de.

    1986-01-01

    The dosimetry and monitoring characteristics of thin X-ray beams, and the application of 4MeV linear particle accelerator to radiosurgery are studied. An addition collimation system, consisted of 3 lead collimators, which allows to obtain thin beams of 6,10 and 15 mm of diameter, was fabricated. The stereo taxic system, together with modifications in dispositives, provide the accuracy required in volum-targed location. The dosimetric informations were determined with silicon detector inserted into water simulator. The isodose curves for each beam, and total isodoses simulating the treatment were established using radiographic emulsions in conditions which reproduce real circunstances of pacient irradiation. (M.C.K.) [pt

  3. Characterizing transverse coherence of an ultra-intense focused X-ray free-electron laser by an extended Young's experiment

    Directory of Open Access Journals (Sweden)

    Ichiro Inoue

    2015-11-01

    Full Text Available Characterization of transverse coherence is one of the most critical themes for advanced X-ray sources and their applications in many fields of science. However, for hard X-ray free-electron laser (XFEL sources there is very little knowledge available on their transverse coherence characteristics, despite their extreme importance. This is because the unique characteristics of the sources, such as the ultra-intense nature of XFEL radiation and the shot-by-shot fluctuations in the intensity distribution, make it difficult to apply conventional techniques. Here, an extended Young's interference experiment using a stream of bimodal gold particles is shown to achieve a direct measurement of the modulus of the complex degree of coherence of XFEL pulses. The use of interference patterns from two differently sized particles enables analysis of the transverse coherence on a single-shot basis without a priori knowledge of the instantaneous intensity ratio at the particles. For a focused X-ray spot as small as 1.8 µm (horizontal × 1.3 µm (vertical with an ultrahigh intensity that exceeds 1018 W cm−2 from the SPring-8 Ångstrom Compact free-electron LAser (SACLA, the coherence lengths were estimated to be 1.7 ± 0.2 µm (horizontal and 1.3 ± 0.1 µm (vertical. The ratios between the coherence lengths and the focused beam sizes are almost the same in the horizontal and vertical directions, indicating that the transverse coherence properties of unfocused XFEL pulses are isotropic. The experiment presented here enables measurements free from radiation damage and will be readily applicable to the analysis of the transverse coherence of ultra-intense nanometre-sized focused XFEL beams.

  4. Providing x-rays

    International Nuclear Information System (INIS)

    Mallozzi, P.J.; Epstein, H.M.

    1985-01-01

    This invention provides an apparatus for providing x-rays to an object that may be in an ordinary environment such as air at approximately atmospheric pressure. The apparatus comprises: means (typically a laser beam) for directing energy onto a target to produce x-rays of a selected spectrum and intensity at the target; a fluid-tight enclosure around the target; means for maintaining the pressure in the first enclosure substantially below atmospheric pressure; a fluid-tight second enclosure adjoining the first enclosure, the common wall portion having an opening large enough to permit x-rays to pass through but small enough to allow the pressure reducing means to evacuate gas from the first enclosure at least as fast as it enters through the opening; the second enclosure filled with a gas that is highly transparent to x-rays; the wall of the second enclosure to which the x-rays travel having a portion that is highly transparent to x-rays (usually a beryllium or plastic foil), so that the object to which the x-rays are to be provided may be located outside the second enclosure and adjacent thereto and thus receive the x-rays substantially unimpeded by air or other intervening matter. The apparatus is particularly suited to obtaining EXAFS (extended x-ray fine structure spectroscopy) data on a material

  5. Alkali-developable silicone-based negative photoresist (SNP) for deep UV, electron beam, and X-ray lithographies

    International Nuclear Information System (INIS)

    Ban, Hiroshi; Tanaka, Akinobu; Kawai, Yoshio; Deguchi, Kimiyoshi

    1989-01-01

    A new silicone-based negative photoresist (SNP) developable with alkaline aqueous solutions is prepared. SNP composed of acetylated phenylsilsesquioxane oligomer and azidopyrene is applied to deep UV, electron beam (EB), and X-ray lithographies. SNP slightly swells in alkaline developers, thus exhibiting exceptionally high resolution characteristics for a negative resist. The resistance of SNP to oxygen reactive ion etching is approximately 30 times greater than that of conventional novolac resists. (author)

  6. Peculiar time dependence of unexpected lines in delayed beam-foil X-ray spectra of V, Fe and Ni

    International Nuclear Information System (INIS)

    Ahmad, Nissar; Karn, Ranjeet K.; Marketos, Pan; Nandi, T.

    2005-01-01

    Delayed beam-foil X-ray spectra of highly charged ions of V, Fe and Ni show a few lines at energies higher than the H-like Lyman α-line of the respective projectile ions. These can only be attributed to heavier ions. Further the time dependence of such unexpected lines display a peculiar behavior. This work presents the experimental observations systematically

  7. Time-dependent, x-ray spectral unfolds and brightness temperatures for intense Li+ ion beam-driven hohlraums

    International Nuclear Information System (INIS)

    Fehl, D.L.; Chandler, G.A.; Biggs, F.; Dukart, R.J.; Moats, A.R.; Leeper, R.J.

    1996-01-01

    X-ray-producing hohlraums are being studied as indirect drives for Inertial Confinement Fusion targets. In a 1994 target series on the PBFAII accelerator, cylindrical hohlraum targets were heated by an intense Li + ion beam and viewed by an array of 13 time-resolved, filtered x-ray detectors (XRDs). The UFO unfold code and its suite of auxiliary functions were used extensively in obtaining time- resolved x-ray spectra and radiation temperatures from this diagnostic. UFO was also used to obtain fitted response functions from calibration data, to simulate data from blackbody x-ray spectra of interest, to determine the suitability of various unfolding parameters (e.g., energy domain, energy partition, smoothing conditions, and basis functions), to interpolate the XRD signal traces, and to unfold experimental data. The simulation capabilities of the code were useful in understanding an anomalous feature in the unfolded spectra at low photon energies (≤ 100 eV). Uncertainties in the differential and energy-integrated unfolded spectra were estimated from uncertainties in the data. The time-history of the radiation temperature agreed well with independent calculations of the wall temperature in the hohlraum

  8. Time-dependent, x-ray spectral unfolds and brightness temperatures for intense Li+ ion beam-driven hohlraums

    International Nuclear Information System (INIS)

    Fehl, D.L.; Chandler, G.A.; Biggs, F.; Dukart, R.J.; Moats, A.R.; Leeper, R.J.

    1997-01-01

    X-ray-producing hohlraums are being studied as indirect drives for inertial confinement fusion targets. In a 1994 target series on the PBFAII accelerator, cylindrical hohlraum targets were heated by an intense Li + ion beam and viewed by an array of 13 time-resolved, filtered x-ray detectors (XRDs). The unfold operator (UFO) code and its suite of auxiliary functions were used extensively in obtaining time-resolved x-ray spectra and radiation temperatures from this diagnostic. The UFO was also used to obtain fitted response functions from calibration data, to simulate data from blackbody x-ray spectra of interest, to determine the suitability of various unfolding parameters (e.g., energy domain, energy partition, smoothing conditions, and basis functions), to interpolate the XRD signal traces, and to unfold experimental data. The simulation capabilities of the code were useful in understanding an anomalous feature in the unfolded spectra at low photon energies (≤100 eV). Uncertainties in the differential and energy-integrated unfolded spectra were estimated from uncertainties in the data. The time endash history of the radiation temperature agreed well with independent calculations of the wall temperature in the hohlraum. copyright 1997 American Institute of Physics

  9. X-ray diffraction imaging with the Multiple Inverse Fan Beam topology: principles, performance and potential for security screening.

    Science.gov (United States)

    Harding, G; Fleckenstein, H; Kosciesza, D; Olesinski, S; Strecker, H; Theedt, T; Zienert, G

    2012-07-01

    The steadily increasing number of explosive threat classes, including home-made explosives (HMEs), liquids, amorphous and gels (LAGs), is forcing up the false-alarm rates of security screening equipment. This development can best be countered by increasing the number of features available for classification. X-ray diffraction intrinsically offers multiple features for both solid and LAGs explosive detection, and is thus becoming increasingly important for false-alarm and cost reduction in both carry-on and checked baggage security screening. Following a brief introduction to X-ray diffraction imaging (XDI), which synthesizes in a single modality the image-forming and material-analysis capabilities of X-rays, the Multiple Inverse Fan Beam (MIFB) XDI topology is described. Physical relationships obtaining in such MIFB XDI components as the radiation source, collimators and room-temperature detectors are presented with experimental performances that have been achieved. Representative X-ray diffraction profiles of threat substances measured with a laboratory MIFB XDI system are displayed. The performance of Next-Generation (MIFB) XDI relative to that of the 2nd Generation XRD 3500TM screener (Morpho Detection Germany GmbH) is assessed. The potential of MIFB XDI, both for reducing the exorbitant cost of false alarms in hold baggage screening (HBS), as well as for combining "in situ" liquid and solid explosive detection in carry-on luggage screening is outlined. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Development of refractive X-ray focusing optics at Diamond Light Source

    Science.gov (United States)

    Alianelli, L.; Sawhney, K. J. S.; Loader, I. M.; Jenkins, D. W. K.; Stevens, R.; Snigirev, A.; Snigireva, I.

    2007-09-01

    The Diamond Optics & Metrology Group and the collaborators at the STFC Central Microstructure Facility have initiated a program for the design and fabrication of in-line micro- and nano-focusing optics for synchrotron radiation beamlines. The first type of optics fabricated is a kinoform lens in silicon on the same model proposed by K. Evans- Lutterodt et al [Opt. Expr. 11 (2003) 919.]. The fabrication utilised ultra high resolution electron beam lithographic patterning of an electron sensitive SU8 polymer and deep reactive ion etching of silicon. The first test of the focusing properties was performed at the ESRF BM5 optics beamline. In this paper we present details on the design and fabrication, and discuss the test results.

  11. Final focus test beam

    International Nuclear Information System (INIS)

    1991-03-01

    This report discusses the following: the Final Focus Test Beam Project; optical design; magnets; instrumentation; magnetic measurement and BPM calibration; mechanical alignment and stabilization; vacuum system; power supplies; control system; radiation shielding and personnel protection; infrastructure; and administration

  12. Development of miniaturized proximity focused streak tubes for visible light and x-ray applications. Final report and progress, April-September 1977

    International Nuclear Information System (INIS)

    Cuny, J.J.; Knight, A.J.

    1978-02-01

    Research performed to develop miniaturized proximity focused streak camera tubes (PFST) for application in the visible and the x-ray modes of operation is described. The objective of this research was to provide an engineering design and to fabricate a visible and an x-ray prototype tube to be provided to LASL for test and evaluation. Materials selection and fabrication procedures, particularly the joining of beryllium to a suitable support ring for use as the x-ray window, are described in detail. The visible and x-ray PFST's were successfully fabricated

  13. Calibration of the Nustar High-Energy Focusing X-Ray Telescope

    DEFF Research Database (Denmark)

    Madsen, Kristin K.; Harrison, Fiona A.; Markwardt, Craig B.

    2015-01-01

    We present the calibration of the Nuclear Spectroscopic Telescope Array (NuSTAR) X-ray satellite. We used the Crab as the primary effective area calibrator and constructed a piece-wise linear spline function to modify the vignetting response. The achieved residuals for all off-axis angles...... and energies, compared to the assumed spectrum, are typically better than +/- 2% up to 40 keV and 5%-10% above due to limited counting statistics. An empirical adjustment to the theoretical two-dimensional point-spread function (PSF) was found using several strong point sources, and no increase of the PSF half-power...

  14. Investigation of the applicability of a special parallel-plate ionization chamber for x-ray beam dosimetry

    International Nuclear Information System (INIS)

    Perini, Ana P.; Neves, Lucio P.; Caldas, Linda V.E.

    2014-01-01

    Diagnostic x-rays are the greatest source of exposition to ionizing radiation of the population worldwide. In order to obtain accurate and lower-cost dosimeters for quality control assurance of medical x-ray facilities, a special ionization chamber was designed at the Calibration Laboratory of the IPEN, for dosimetry in diagnostic radiology beams. For the chamber characterization some tests were undertaken. Monte Carlo simulations were proposed to evaluate the distribution of the deposited energy in the sensitive volume of the ionization chamber and the collecting electrode effect on the chamber response. According to the obtained results, this special ionization chamber presents potential use for dosimetry of conventional diagnostic radiology beams. - Highlights: • An ionization chamber with a novel design was characterized for x-ray beam dosimetry. • This ionization chamber was evaluated in diagnostic radiology qualities. • The characterization tests results were within the recommended limits. • Monte Carlo simulations were employed to evaluate the design of the dosimeter. • The developed prototype is a good alternative for calibration laboratories and clinics

  15. Optimizing contrast agents with respect to reducing beam hardening in nonmedical X-ray computed tomography experiments.

    Science.gov (United States)

    Nakashima, Yoshito; Nakano, Tsukasa

    2014-01-01

    Iodine is commonly used as a contrast agent in nonmedical science and engineering, for example, to visualize Darcy flow in porous geological media using X-ray computed tomography (CT). Undesirable beam hardening artifacts occur when a polychromatic X-ray source is used, which makes the quantitative analysis of CT images difficult. To optimize the chemistry of a contrast agent in terms of the beam hardening reduction, we performed computer simulations and generated synthetic CT images of a homogeneous cylindrical sand-pack (diameter, 28 or 56 mm; porosity, 39 vol.% saturated with aqueous suspensions of heavy elements assuming the use of a polychromatic medical CT scanner. The degree of cupping derived from the beam hardening was assessed using the reconstructed CT images to find the chemistry of the suspension that induced the least cupping. The results showed that (i) the degree of cupping depended on the position of the K absorption edge of the heavy element relative to peak of the polychromatic incident X-ray spectrum, (ii) (53)I was not an ideal contrast agent because it causes marked cupping, and (iii) a single element much heavier than (53)I ((64)Gd to (79)Au) reduced the cupping artifact significantly, and a four-heavy-element mixture of elements from (64)Gd to (79)Au reduced the artifact most significantly.

  16. Propagation of modulated electron and X-ray beams through matter and interactions with radio-frequency structures

    Science.gov (United States)

    Harris, J. R.; Miller, R. B.

    2018-02-01

    The generation and evolution of modulated particle beams and their interactions with resonant radiofrequency (RF) structures are of fundamental interest for both particle accelerator and vacuum electronic systems. When the constraint of propagation in a vacuum is removed, the evolution of such beams can be greatly affected by interactions with matter including scattering, absorption, generation of atmospheric plasma, and the production of multiple generations of secondary particles. Here, we study the propagation of 21 MeV and 25 MeV electron beams produced in S-band and L-band linear accelerators, and their interaction with resonant RF structures, under a number of combinations of geometry, including transmission through both air and metal. Both resonant and nonresonant interactions were observed, with the resonant interactions indicating that the RF modulation on the electron beam is at least partially preserved as the beam propagates through air and metal. When significant thicknesses of metal are placed upstream of a resonant structure, preventing any primary beam electrons from reaching the structure, RF signals could still be induced in the structures. This indicated that the RF modulation present on the electron beam was also impressed onto the x-rays generated when the primary electrons were stopped in the metal, and that this RF modulation was also present on the secondary electrons generated when the x-rays struck the resonant structures. The nature of these interactions and their sensitivities to changes in system configurations will be discussed.

  17. A beam optics study of a modular multi-source X-ray tube for novel computed tomography applications

    Science.gov (United States)

    Walker, Brandon J.; Radtke, Jeff; Chen, Guang-Hong; Eliceiri, Kevin W.; Mackie, Thomas R.

    2017-10-01

    A modular implementation of a scanning multi-source X-ray tube is designed for the increasing number of multi-source imaging applications in computed tomography (CT). An electron beam array coupled with an oscillating magnetic deflector is proposed as a means for producing an X-ray focal spot at any position along a line. The preliminary multi-source model includes three thermionic electron guns that are deflected in tandem by a slowly varying magnetic field and pulsed according to a scanning sequence that is dependent on the intended imaging application. Particle tracking simulations with particle dynamics analysis software demonstrate that three 100 keV electron beams are laterally swept a combined distance of 15 cm over a stationary target with an oscillating magnetic field of 102 G perpendicular to the beam axis. Beam modulation is accomplished using 25 μs pulse widths to a grid electrode with a reverse gate bias of -500 V and an extraction voltage of +1000 V. Projected focal spot diameters are approximately 1 mm for 138 mA electron beams and the stationary target stays within thermal limits for the 14 kW module. This concept could be used as a research platform for investigating high-speed stationary CT scanners, for lowering dose with virtual fan beam formation, for reducing scatter radiation in cone-beam CT, or for other industrial applications.

  18. Accuracy of cranial coplanar beam therapy using an oblique, stereoscopic x-ray image guidance system

    International Nuclear Information System (INIS)

    Vinci, Justin P.; Hogstrom, Kenneth R.; Neck, Daniel W.

    2008-01-01

    A system for measuring two-dimensional (2D) dose distributions in orthogonal anatomical planes in the cranium was developed and used to evaluate the accuracy of coplanar conformal therapy using ExacTrac image guidance. Dose distributions were measured in the axial, sagittal, and coronal planes using a CIRS (Computerized Imaging Reference Systems, Inc.) anthropomorphic head phantom with a custom internal film cassette. Sections of radiographic Kodak EDR2 film were cut, processed, and digitized using custom templates. Spatial and dosimetric accuracy and precision of the film system were assessed. BrainScan planned a coplanar-beam treatment to conformally irradiate a 2-cm-diameterx2-cm-long cylindrical planning target volume. Prior to delivery, phantom misalignments were imposed in combinations of ±8 mm offsets in each of the principal directions. ExacTrac x-ray correction was applied until the phantom was within an acceptance criteria of 1 mm/1 deg. (first two measurement sets) or 0.4 mm/0.4 deg. (last two measurement sets). Measured dose distributions from film were registered to the treatment plan dose calculations and compared. Alignment errors, displacement between midpoints of planned and measured 70% isodose contours (Δc), and positional errors of the 80% isodose line were evaluated using 49 2D film measurements (98 profiles). Comparison of common, but independent measurements of Δc showed that systematic errors in the measurement technique were 0.2 mm or less along all three anatomical axes and that random error averaged (σ±σ σ ) 0.29±0.06 mm for the acceptance criteria of 1 mm/1 deg. and 0.15±0.02 mm for the acceptance criteria of 0.4 mm/0.4 deg. . The latter was consistent with independent estimates that showed the precision of the measurement system was 0.3 mm (2σ). Values of Δc were as great as 0.9, 0.3, and 1.0 mm along the P-A, R-L, and I-S axes, respectively. Variations in Δc along the P-A axis were correlated to misalignments between laser

  19. Specific features of X-ray generation by plasma focus chambers with deuterium and deuterium–tritium fillings

    Energy Technology Data Exchange (ETDEWEB)

    Dulatov, A. K., E-mail: bogolubov@vniia.ru; Krapiva, P. S.; Lemeshko, B. D.; Mikhailov, Yu. V.; Moskalenko, I. N.; Prokuratov, I. A.; Selifanov, A. N. [All-Russia Research Institute of Automatics (Russian Federation)

    2016-01-15

    The process of hard X-ray (HXR) generation in plasma focus (PF) chambers was studied experimentally. The radiation was recorded using scintillation detectors with a high time resolution and thermoluminescent detectors in combination with the method of absorbing filters. Time-resolved analysis of the processes of neutron and X-ray generation in PFs is performed. The spectra of HXR emission from PF chambers with deuterium and deuterium–tritium fillings are determined. In experiments with PF chambers filled with a deuterium–tritium mixture, in addition to the HXR pulse with photon energies of up to 200–300 keV, a γ-ray pulse with photon energies of up to 2.5–3.0 MeV is recorded, and a mechanism of its generation is proposed.

  20. Is low-energy-ion bombardment generated X-ray emission a secondary mutational source to ion-beam-induced genetic mutation?

    Energy Technology Data Exchange (ETDEWEB)

    Thongkumkoon, P. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand); Prakrajang, K. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Faculty of Science, Maejo University, Chiang Mai 50290 (Thailand); Thopan, P.; Yaopromsiri, C. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Suwannakachorn, D. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand); Yu, L.D., E-mail: yuld@fnrf.science.cmu.ac.th [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand)

    2013-07-15

    Highlights: ► Detected X-ray emission from metal, plastic and biological samples. ► Characteristic X-ray emission was detected from metal but not from non-metals. ► Low-energy ion bombarded bacteria held in different sample holders. ► Bacteria held in metal holder had higher mutation rate than in plastic holder. ► Ion-beam-induced X-ray from biological sample is not a basic mutation source. -- Abstract: Low-energy ion beam biotechnology has achieved tremendous successes in inducing crop mutation and gene transfer. However, mechanisms involved in the related processes are not yet well understood. In ion-beam-induced mutation, ion-bombardment-produced X-ray has been proposed to be one of the secondary mutation sources, but the speculation has not yet been experimentally tested. We carried out this investigation to test whether the low-energy ion-beam-produced X-ray was a source of ion-beam-induced mutation. In the investigation, X-ray emission from 29-keV nitrogen- or argon- ion beam bombarded bacterial Escherichia coli (E. coli) cells held in a metal or plastic sample holder was in situ detected using a highly sensitive X-ray detector. The ion beam bombarded bacterial cells held in different material holders were observed for mutation induction. The results led to a conclusion that secondary X-ray emitted from ion-beam-bombarded biological living materials themselves was not a, or at least a negligible, mutational source, but the ion-beam-induced X-ray emission from the metal that made the sample holder could be a source of mutation.

  1. Is low-energy-ion bombardment generated X-ray emission a secondary mutational source to ion-beam-induced genetic mutation?

    International Nuclear Information System (INIS)

    Thongkumkoon, P.; Prakrajang, K.; Thopan, P.; Yaopromsiri, C.; Suwannakachorn, D.; Yu, L.D.

    2013-01-01

    Highlights: ► Detected X-ray emission from metal, plastic and biological samples. ► Characteristic X-ray emission was detected from metal but not from non-metals. ► Low-energy ion bombarded bacteria held in different sample holders. ► Bacteria held in metal holder had higher mutation rate than in plastic holder. ► Ion-beam-induced X-ray from biological sample is not a basic mutation source. -- Abstract: Low-energy ion beam biotechnology has achieved tremendous successes in inducing crop mutation and gene transfer. However, mechanisms involved in the related processes are not yet well understood. In ion-beam-induced mutation, ion-bombardment-produced X-ray has been proposed to be one of the secondary mutation sources, but the speculation has not yet been experimentally tested. We carried out this investigation to test whether the low-energy ion-beam-produced X-ray was a source of ion-beam-induced mutation. In the investigation, X-ray emission from 29-keV nitrogen- or argon- ion beam bombarded bacterial Escherichia coli (E. coli) cells held in a metal or plastic sample holder was in situ detected using a highly sensitive X-ray detector. The ion beam bombarded bacterial cells held in different material holders were observed for mutation induction. The results led to a conclusion that secondary X-ray emitted from ion-beam-bombarded biological living materials themselves was not a, or at least a negligible, mutational source, but the ion-beam-induced X-ray emission from the metal that made the sample holder could be a source of mutation

  2. Applications of capillary optics for focused ion beams

    International Nuclear Information System (INIS)

    Umezawa, Kenji

    2014-01-01

    This article introduces applications of focused ion beams (∼1 μm) with glass capillaries systems. A first report on the interaction between ion beams and glass capillaries was published in 1996. The guiding capabilities of glass capillaries were discovered due to ion reflection from inner wall of glass surfaces. Meanwhile, the similar optics have been already realized in focusing X-rays using glass capillaries. The basic technology of X-rays optics using glass capillaries had been developed in the 1980's and 1900's. Also, low energy atom scattering spectroscopy for insulator material analysis will be mentioned. (author)

  3. CALIBRATION OF THE NuSTAR HIGH-ENERGY FOCUSING X-RAY TELESCOPE

    Energy Technology Data Exchange (ETDEWEB)

    Madsen, Kristin K.; Harrison, Fiona A.; Grefenstette, Brian W.; Miyasaka, Hiromasa; Forster, Karl; Fuerst, Felix; Rana, Vikram; Walton, Dominic J. [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Markwardt, Craig B. [Goddard Space Flight Center, Greenbelt, MD 20771 (United States); An, Hongjun [Department of Physics, McGill University, Montreal, Quebec, H3A 2T8 (Canada); Bachetti, Matteo [Université de Toulouse, UPS-OMP, IRAP, Toulouse (France); Kitaguchi, Takao [RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198 (Japan); Bhalerao, Varun [Inter-University Center for Astronomy and Astrophysics, Post Bag 4, Ganeshkhind, Pune 411007 (India); Boggs, Steve; Craig, William W. [Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States); Christensen, Finn E. [DTU Space, National Space Institute, Technical University of Denmark, Elektronvej 327, DK-2800 Lyngby (Denmark); Hailey, Charles J. [Columbia Astrophysics Laboratory, Columbia University, NY 10027 (United States); Perri, Matteo; Puccetti, Simonetta [ASI Science Data Center, via Galileo Galilei, I-00044, Frascati (Italy); Stern, Daniel [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); and others

    2015-09-15

    We present the calibration of the Nuclear Spectroscopic Telescope Array (NuSTAR) X-ray satellite. We used the Crab as the primary effective area calibrator and constructed a piece-wise linear spline function to modify the vignetting response. The achieved residuals for all off-axis angles and energies, compared to the assumed spectrum, are typically better than ±2% up to 40 keV and 5%–10% above due to limited counting statistics. An empirical adjustment to the theoretical two-dimensional point-spread function (PSF) was found using several strong point sources, and no increase of the PSF half-power diameter has been observed since the beginning of the mission. We report on the detector gain calibration, good to 60 eV for all grades, and discuss the timing capabilities of the observatory, which has an absolute timing of ±3 ms. Finally, we present cross-calibration results from two campaigns between all the major concurrent X-ray observatories (Chandra, Swift, Suzaku, and XMM-Newton), conducted in 2012 and 2013 on the sources 3C 273 and PKS 2155-304, and show that the differences in measured flux is within ∼10% for all instruments with respect to NuSTAR.

  4. X-Band Linac Beam-Line for Medical Compton Scattering X-Ray Source

    CERN Document Server

    Dobashi, Katsuhiro; Ebina, Futaro; Fukasawa, Atsushi; Hayano, Hitoshi; Higo, Toshiyasu; Kaneyasu, Tatsuo; Ogino, Haruyuki; Sakamoto, Fumito; Uesaka, Mitsuru; Urakawa, Junji; Yamamoto, Tomohiko

    2005-01-01

    Compton scattering hard X-ray source for 10~80 keV are under construction using the X-band (11.424 GHz) electron linear accelerator and YAG laser at Nuclear Engineering Research laboratory, University of Tokyo. This work is a part of the national project on the development of advanced compact medical accelerators in Japan. National Institute for Radiological Science is the host institute and U. Tokyo and KEK are working for the X-ray source. Main advantage is to produce tunable monochromatic hard ( 10-80

  5. An extended range soft X-ray beam line for the 1 GeV storage ring Aladdin

    International Nuclear Information System (INIS)

    Hulbert, S.L.; Stott, J.P.; Brown, F.C.

    1983-01-01

    The design and implementation of a soft X-ray beam line on the new 1 GeV storage ring Aladdin in Stoughton, Wisconsin is discussed. The beam line consists of a long horizontally focussing collection mirror, an extended range (50-1500 eV) grasshopper monochromator, an ellipsoidal refocussing mirror, and a photoemission chamber. Also discussed are the factors considered in matching the monochromator to the storage ring, flux and performance expectations, and the results of a ray tracing analysis. (orig.)

  6. Study of electron beam effects on surfaces using x-ray photoelectron spectroscopy (XPS) and secondary ion mass spectroscopy (SIMS)

    International Nuclear Information System (INIS)

    Gettings, M.; Coad, J.P.

    1976-02-01

    Discrepancies in the surface analyses of oxidised or heavily contaminated materials have been observed between X-ray Photoelectron Spectroscopy (XPS) and techniques using electron beams (primarily Auger Electron Spectroscopy (AES)). These discrepancies can be ascribed to the influence of the primary electron beam and to illustrate the various types of electron effects different materials were analysed using XPS and Secondary Ion Mass Spectroscopy (SIMS) before and after large area electron bombardment. The materials used included chrome and stainless steels, nickel, platinum, glass and brass. (author)

  7. X-ray detector array

    International Nuclear Information System (INIS)

    Houston, J.M.

    1980-01-01

    The object of the invention (an ionization chamber X-ray detector array for use with high speed computerised tomographic imaging apparatus) is to reduce the time required to produce a tomographic image. The detector array described determines the distribution of X-ray intensities in one or more flat, coplanar X-ray beams. It comprises three flat anode sheets parallel to the X-ray beam, a plurality of rod-like cathodes between the anodes, a detector gas between the electrodes and a means for applying a potential between the electrodes. Each of the X-ray sources is collimated to give a narrow, planar section of X-ray photons. Sets of X-ray sources in the array are pulsed simultaneously to obtain X-ray transmission data for tomographic image reconstruction. (U.K.)

  8. Soft X-ray generation via inverse compton scattering between high quality electron beam and high power laser

    International Nuclear Information System (INIS)

    Masakazu Washio; Kazuyuki Sakaue; Yoshimasa Hama; Yoshio Kamiya; Tomoko Gowa; Akihiko Masuda; Aki Murata; Ryo Moriyama; Shigeru Kashiwagi; Junji Urakawa

    2007-01-01

    High quality beam generation project based on High-Tech Research Center Project, which has been approved by Ministry of Education, Culture, Sports, Science and Technology in 1999, has been conducted by advance research institute for science and engineering, Waseda University. In the project, laser photo-cathode RF-gun has been selected for the high quality electron beam source. RF cavities with low dark current, which were made by diamond turning technique, have been successfully manufactured. The low emittance electron beam was realized by choosing the modified laser injection technique. The obtained normalized emmitance was about 3 m.mrad at 100 pC of electron charge. The soft x-ray beam generation with the energy of 370 eV, which is in the energy region of so-called water window, by inverse Compton scattering has been performed by the collision between IR laser and the low emmitance electron beams. (Author)

  9. Characterization of a multi-keV x-ray source produced by nanosecond laser irradiation of a solid target: The influence of laser focus spot and target thickness

    International Nuclear Information System (INIS)

    Hu Guangyue; Zheng Jian; Shen Baifei; Lei Anle; Xu Zhizhan; Liu Shenye; Zhang Jiyan; Yang Jiamin; Ding Yongkun; Hu Xin; Huang Yixiang; Du Huabing; Yi Rongqing

    2008-01-01

    The influence of focus spot and target thickness on multi-keV x-ray sources generated by 2 ns duration laser heated solid targets are investigated on the Shenguang II laser facility. In the case of thick-foil targets, the experimental data and theoretical analysis show that the emission volume of the x-ray sources is sensitive to the laser focus spot and proportional to the 3 power of the focus spot size. The steady x-ray flux is proportional to the 5/3 power of the focus spot size of the given laser beam in our experimental condition. In the case of thin-foil targets, experimental data show that there is an optimal foil thickness corresponding to the given laser parameters. With the given laser beam, the optimal thin-foil thickness is proportional to the -2/3 power of the focus spot size, and the optimal x-ray energy of thin foil is independent of focus spot size

  10. Morphology of bone defects in patient with unilateral cleft lip and palate. Cone beam x-ray CT evaluation

    International Nuclear Information System (INIS)

    Kyo, Iyu; Kubota, Masato; Sato, Yuki; Nakano, Haruhisa; Maki, Koutaro

    2006-01-01

    Orthodontic treatment planning of the cleft lip and palate vary according to the morphology of the alveolar bone and palatal bone. The purpose of this study is to evaluate the three-dimensional anatomy of the alveolar and palatal bone in children with complete unilateral cleft lip and palate. Thirty-three nonsyndromic consecutive patients with complete unilateral cleft lip and palate were treated by the cleft palate team at Showa University. Each patient had lip and palate surgeries at Showa University. Cone beam CT radiographs (CB MercuRay, Hitachi) were taken prior to secondary bone grafting, and were classified according to the method of Kita et al. 1997. Cone beam CT radiographs showed multiple types of alveolar and palatal bone morphology, and focused on special types described in the method of Kita et al. It was most frequently found that bone defects in the alveolar crest showed similar patterns in both buccal and palatal aspect, and the buccal bone defect in the nasal floor was larger than the palatal bone defect in the nasal floor. In 80% of the patients, the palatal bone defect showed similar patterns in both anterior and posterior aspects, and the anterior palatal bone defect was smaller than the posterior palatal bone defect. In addition, inadequate bone bridges were frequently found at the cleft site. It is suggested that patients with unilateral cleft lip and palate have various types of alveolar and palatal bone morphology, and are required to take three-dimensional radiographic X-rays prior to any orthodontic treatment. (author)

  11. Precision white-beam slit design for high power density x-ray undulator beamlines at the Advanced Photon Source

    International Nuclear Information System (INIS)

    Shu, D.; Brite, C.; Nian, T.

    1994-01-01

    A set of precision horizontal and vertical white-beam slits has been designed for the Advanced Photon Source (APS) X-ray undulator beamlines at Argonne National Laboratory. There are several new design concepts applied in this slit set, including: grazing-incidence knife-edge configuration to minimize the scattering of X-rays downstream, enhanced heat transfer tubing to provide water cooling, and a second slit to eliminate the thermal distortion on the slit knife edge. The novel aspect of this design is the use of two L-shaped knife-edge assemblies, which are manipulated by two precision X-Z stepping linear actuators. The principal and structural details of the design for this slit set are presented in this paper

  12. Thin film beam splitter multiple short pulse generation for enhanced Ni-like Ag x-ray laser emission.

    Science.gov (United States)

    Cojocaru, Gabriel V; Ungureanu, Razvan G; Banici, Romeo A; Ursescu, Daniel; Delmas, Olivier; Pittman, Moana; Guilbaud, Olivier; Kazamias, Sophie; Cassou, Kevin; Demailly, Julien; Neveu, Olivier; Baynard, Elsa; Ros, David

    2014-04-15

    An alternative, novel multiple pulse generation scheme was implemented directly after the optical compressor output of an x-ray pump laser. The new method uses a polarization sensitive thin film beam splitter and a half-wavelength wave plate for tuning the energy ratio in the multiple short pulses. Based on this method, an extensive study was made of the running parameters for a grazing incidence pumped silver x-ray laser (XRL) pumped with a long pulse of 145 mJ in 6 ns at 532 nm and up to 1.45 J in few picoseconds at 810 nm. Fivefold enhancement in the emission of the silver XRL was demonstrated using the new pump method.

  13. Analysis of the procedures and criteria for implantation of X-ray beams for ISO 4037 reference at low energies

    International Nuclear Information System (INIS)

    Figueiredo, Marcus Tadeu Tanuri de

    2012-01-01

    According to the radiological protection principles, practices involving ionizing radiation must be planned and carried out under the guarantee that the values of individual doses, the number of people exposed to radiation and the probability of accidental exposures are as low as reasonably achievable. Therefore, radiation dosimetry is required to be done with reliable instruments designed for measuring dosimetric quantities. The reliability of the dosimetry depends on both the calibration of the dosimeter and its proper performance under certain test conditions. The International Standardization Organization (ISO), in order to promote international standardization and metrological coherency, established sets of reference X-ray beams for dosimeter calibration and typing-test; they are expected to be implemented in metrology laboratories in compliance with specific technical requirements. At low energies there are specific requirements that need to be considered in both the implementation of the reference beams and their use in calibration and testing. The present study is an analysis of the procedures and criteria for ISO 4037 reference radiation implementation, at low energies. In the Dosimeter Calibration Laboratory of the Development Center of Nuclear Technology (LCD / CDTN), experiments were performed for determining the X-ray reference radiation parameters. Alternatives to the usual methods for half-value layer determination were studied. Spectra of reference beams were simulated with software and compared with experimental measurements. Different climatic conditions were reproduced in the Laboratory for analysis of its influence on the determination of the beam parameters. Uncertainties in the measurements of studied parameters were evaluated. According to the ISO 4037 criteria, the low energy X-ray beams were considered to be implemented; they allowed the determination of the conversion coefficients from air kerma to the operational radiation protection

  14. Feasibility of X-ray analysis of multi-layer thin films at a single beam voltage

    International Nuclear Information System (INIS)

    Statham, P J

    2010-01-01

    Multi-layer analysis using electron beam excitation and X-ray spectrometry is a powerful tool for characterising layers down to 1 nm thickness and with typically 1 μm lateral resolution but does not always work. Most published applications have used WDS with many measurements at different beam voltages and considerable experience has been needed to choose lines and voltages particularly for complex multi-layer problems. A new objective mathematical approach is described which demonstrates whether X-ray analysis can obtain reliable results for an arbitrary multi-layer problem. A new algorithm embodied in 'ThinFilmID' software produces a single plot that shows feasibility of achieving results with a single EDS spectrum and suggests the optimal beam voltage. Synthesis of EDS spectra allows the precision in results to be estimated and acquisition conditions modified before wasting valuable instrument time. Thus, practicality of multi-layer thin film analysis at a single beam voltage can now be established without the extensive experimentation that was previously required by a microanalysis expert. Examples are shown where the algorithm discovers viable single-voltage conditions for applications that experts previously thought could only be addressed using measurements at more than one beam voltage.

  15. Gamma-H2AX foci in cells exposed to a mixed beam of X-rays and alpha particles

    Science.gov (United States)

    2012-01-01

    Background Little is known about the cellular effects of exposure to mixed beams of high and low linear energy transfer radiation. So far, the effects of combined exposures have mainly been assessed with clonogenic survival or cytogenetic methods, and the results are contradictory. The gamma-H2AX assay has up to now not been applied in this context, and it is a promising tool for investigating the early cellular response to mixed beam irradiation. Purpose To determine the dose response and repair kinetics of gamma-H2AX ionizing radiation-induced foci in VH10 human fibroblasts exposed to mixed beams of 241Am alpha particles and X-rays. Results VH10 human fibroblasts were irradiated with each radiation type individually or both in combination at 37°C. Foci were scored for repair kinetics 0.5, 1, 3 and 24 h after irradiation (one dose per irradiation type), and for dose response at the 1 h time point. The dose response effect of mixed beam was additive, and the relative biological effectiveness for alpha particles (as compared to X-rays) was of 0.76 ± 0.52 for the total number of foci, and 2.54 ± 1.11 for large foci. The repair kinetics for total number of foci in cells exposed to mixed beam irradiation was intermediate to that of cells exposed to alpha particles and X-rays. However, for mixed beam-irradiated cells the frequency and area of large foci were initially lower than predicted and increased during the first 3 hours of repair (while the predicted number and area did not). Conclusions The repair kinetics of large foci after mixed beam exposure was significantly different from predicted based on the effect of the single dose components. The formation of large foci was delayed and they did not reach their maximum area until 1 h after irradiation. We hypothesize that the presence of low X-ray-induced damage engages the DNA repair machinery leading to a delayed DNA damage response to the more complex DNA damage induced by alpha particles. PMID:23121736

  16. Present status of research and development on X-ray microprobe

    International Nuclear Information System (INIS)

    Koike, Masaki; Suzuki, I.H.

    1991-01-01

    X-ray beam micro-analysis has advanced rapidly in these years in conjunction with the development of powerful X-ray sources. Among a variety of methods being attempted, the method using a collimated narrow beam has been important because of high brightness, and of usability in both regions of soft and hard X-rays. In the soft X-ray region, the focused beam is formed by a fresnel zone plate or a Schwaltzschild mirror assembly, and can be used for scanning transmission microscope or scanning photoelectron microscope. In the hard X-ray region, the beam is formed by grazing incidence mirrors, and can be used for X-ray fluorescence micro-analysis for obtaining elemental mapping. In this report, the recent progress on the soft X-ray scanning microscopy and the X-ray microprobe has been surveyed, together with the improvement on the related optical elements. (author) 84 refs

  17. Electron beam produced in a transient hollow cathode discharge: beam electron distribution function, X-ray emission and solid target ablation

    International Nuclear Information System (INIS)

    Nistor, Magdalena

    2000-01-01

    This research thesis aims at a better knowledge of phenomena occurring during transient hollow cathode discharges. The author first recalls the characteristics of such a discharge which make it different from conventional pseudo-spark discharges. The objective is to characterise the electron beam produced within the discharge, and the phenomena associated with its interaction with a solid or gaseous target, leading to the production of an X ray or visible radiation. Thus, the author reports the measurement (by magnetic deflection) of the whole time-averaged electronic distribution function. Such a knowledge is essential for a better use of the electron beam in applications such as X-ray source or material ablation. As high repetition frequency pulse X ray sources are very interesting tools, he reports the development and characterisation of Bremsstrahlung X rays during a beam-target interaction. He finally addresses the implementation of a spectroscopic diagnosis for the filamentary plasma and the ablation of a solid target by the beam [fr

  18. Intercomparison of ionization chambers in standard X-ray beams, at radiotherapy, diagnostic radiology and radioprotection levels

    International Nuclear Information System (INIS)

    Bessa, Ana Carolina Moreira de

    2007-01-01

    Since the calibration of radiation measurement instruments and the knowledge of their major characteristics are very important subjects, several different types of ionization chambers were inter compared in terms of their calibration coefficients and their energy dependence, in radiotherapy, diagnostic radiology and radioprotection standard beams. An intercomparison of radionuclide calibrators for nuclear medicine was performed, using three radionuclides: 67 Ga, 201 Tl and 99m Tc; the results obtained were all within the requirements of the national standard CNEN-NE-3.05. In order to complete the range of radiation qualities of the Calibration Laboratory of IPEN, standard radiation beam qualities, radiation protection and low energy radiation therapy levels, were established, according international recommendations. Three methodologies for the calibration of unsealed ionization chambers in X-ray beams were studied and compared. A set of Victoreen ionization chambers, specially designed for use in laboratorial intercomparisons, was submitted to characterization tests. The performance of these Victoreen ionization chambers showed that they are suitable for use in radioprotection beams, because the results obtained agree with international recommendations. However, these Victoreen ionization chambers can be used in radiotherapy and diagnostic radiology beams only with some considerations, since their performance in these beams, especially in relation to the energy dependence and stabilization time tests, did not agree with the international recommendations for dosimeters used in radiotherapy and diagnostic radiology beams. This work presents data on the performance of several types of ionization chambers in different X-ray beams, that may be useful for choosing the appropriate instrument for measurements in ionizing radiation beams. (author)

  19. Intercomparison of ionization chambers in standard X-ray beams, at radiotherapy, diagnostic radiology and radioprotection levels

    International Nuclear Information System (INIS)

    Bessa, Ana Carolina Moreira de

    2006-01-01

    Since the calibration of radiation measurement instruments and the knowledge of their major characteristics are very important subjects, several different types of ionization chambers were intercompared in terms of their calibration coefficients and their energy dependence, in radiotherapy, diagnostic radiology and radioprotection standard beams. An intercomparison of radionuclide calibrators for nuclear medicine was performed, using three radionuclides: 67 Ga, 201 Tl and 99m Tc; the results obtained were all within the requirements of the national standard CNEN-NE-3.05. In order to complete the range of radiation qualities of the Calibration Laboratory of IPEN, standard radiation beam qualities, radiation protection and low energy radiation therapy levels, were established, according international recommendations. Three methodologies for the calibration of unsealed ionization chambers in X-ray beams were studied and compared. A set of Victoreen ionization chambers, specially designed for use in laboratorial intercomparisons, was submitted to characterization tests. The performance of these Victoreen ionization chambers showed that they are suitable for use in radioprotection beams, because the results obtained agree with international recommendations. However, these Victoreen ionization chambers can be used in radiotherapy and diagnostic radiology beams only with some considerations, since their performance in these beams, especially in relation to the energy dependence and stabilization time tests, did not agree with the international recommendations for dosimeters used in radiotherapy and diagnostic radiology beams. This work presents data on the performance of several types of ionization chambers in different X-ray beams, that may be useful for choosing the appropriate instrument for measurements in ionizing radiation beams. (author)

  20. Semi-empirical procedures for correcting detector size effect on clinical MV x-ray beam profiles

    International Nuclear Information System (INIS)

    Sahoo, Narayan; Kazi, Abdul M.; Hoffman, Mark

    2008-01-01

    The measured radiation beam profiles need to be corrected for the detector size effect to derive the real profiles. This paper describes two new semi-empirical procedures to determine the real profiles of high-energy x-ray beams by removing the detector size effect from the measured profiles. Measured profiles are corrected by shifting the position of each measurement point by a specific amount determined from available theoretical and experimental knowledge in the literature. The authors developed two procedures to determine the amount of shift. In the first procedure, which employs the published analytical deconvolution procedure of other investigators, the shift is determined from the comparison of the analytical fit of the measured profile and the corresponding analytical real profile derived from the deconvolution of the fitted measured profile and the Gaussian detector response function. In the second procedure, the amount of shift at any measurement point is considered to be proportional to the value of an analytical function related to the second derivative of the real profile at that point. The constant of proportionality and a parameter in the function are obtained from the values of the shifts at the 90%, 80%, 20%, and 10% dose levels, which are experimentally known from the published results of other investigators to be approximately equal to half of the radius of the detector. These procedures were tested by correcting the profiles of 6 and 18 MV x-ray beams measured by three different ionization chambers and a stereotactic field diode detector with 2.75, 2, 1, and 0.3 mm radii of their respective active cylindrical volumes. The corrected profiles measured by different detectors are found to be in close agreement. The detector size corrected penumbra widths also agree with the expected values based on the results of an earlier investigation. Thus, the authors concluded that the proposed procedures are accurate and can be used to derive the real

  1. Characterization of a free-air ionization chamber in direct X-ray beams as used in mammography

    International Nuclear Information System (INIS)

    Lima, Mateus Hilario de

    2014-01-01

    At this work stability and characterization tests were undertaken on a Victoreen free-air ionization chamber, model 481. The tests were realized using direct X-ray beams as a contribution for its establishment as a primary standard system of the quantity air kerma. The characterization tests were: saturation curve, ion collection efficiency, polarity effect, response linearity with the air kerma rate and response linearity with the chamber volume variation. The ion collection efficiency allowed the determination of the ion recombination factor. Most of the test results showed agreement with the limits established by international standards. Furthermore, the air attenuation factors for the mammography beams with aluminum and molybdenum filters were obtained. The factors for photon transmission and scattering at the diaphragm edges were also determined for mammography beams with aluminum filter and for the standard beam with molybdenum filter. (author)

  2. Femtosecond X-ray diffraction from an aerosolized beam of protein nanocrystals.

    Science.gov (United States)

    Awel, Salah; Kirian, Richard A; Wiedorn, Max O; Beyerlein, Kenneth R; Roth, Nils; Horke, Daniel A; Oberthür, Dominik; Knoska, Juraj; Mariani, Valerio; Morgan, Andrew; Adriano, Luigi; Tolstikova, Alexandra; Xavier, P Lourdu; Yefanov, Oleksandr; Aquila, Andrew; Barty, Anton; Roy-Chowdhury, Shatabdi; Hunter, Mark S; James, Daniel; Robinson, Joseph S; Weierstall, Uwe; Rode, Andrei V; Bajt, Saša; Küpper, Jochen; Chapman, Henry N

    2018-02-01

    High-resolution Bragg diffraction from aerosolized single granulovirus nanocrystals using an X-ray free-electron laser is demonstrated. The outer dimensions of the in-vacuum aerosol injector components are identical to conventional liquid-microjet nozzles used in serial diffraction experiments, which allows the injector to be utilized with standard mountings. As compared with liquid-jet injection, the X-ray scattering background is reduced by several orders of magnitude by the use of helium carrier gas rather than liquid. Such reduction is required for diffraction measurements of small macromolecular nanocrystals and single particles. High particle speeds are achieved, making the approach suitable for use at upcoming high-repetition-rate facilities.

  3. Results of a search for paraphotons with intense X-ray beams at SPring-8

    International Nuclear Information System (INIS)

    Inada, T.; Namba, T.; Asai, S.; Kobayashi, T.; Tanaka, Y.; Tamasaku, K.; Sawada, K.; Ishikawa, T.

    2013-01-01

    A search for paraphotons, or hidden U(1) gauge bosons, is performed using an intense X-ray beamline at SPring-8. “Light Shining through a Wall” technique is used in this search. No excess of events above background is observed. A stringent constraint is obtained on the photon–paraphoton mixing angle, χ −5 (95% C.L.) for 0.04 eV γ ′ <26 keV

  4. Parametric curve evaluation of a phototransistor used as detector in stereotactic radiosurgery X-ray beam

    International Nuclear Information System (INIS)

    Lima, Daniela Pontes A.; Santos, Luiz Antonio P.; Santos, Walter M.; Silva Junior, Eronides F. da

    2005-01-01

    Phototransistors have been widely used as detectors for low energy X-rays. However, when they are used in high energy X-rays fields like those generated from linear accelerators (linac), there is a certain loss of sensibility to the ionizing radiation. This damage is cumulative and irreversible. Thus, a correction factor must be applied to its response, which is proportional to the integrated dose. However, it is possible to estimate the correction factor by using the V x I parametric curve of the device. The aim of this work was to develop studies to evaluate and correlate the parametric response curve of a phototransistor with its loss of sensibility after irradiation. An Agilent 4155C semiconductor parameter analyzer was used to trace the parametric curve. X-rays were generated by a 14 MV Primus-Siemens linear accelerator. The results demonstrated that there is a correlation between the integrated dose applied to the phototransistor and the parametric response of the device. Studies are under way to determine how such behavior can provide information for the dosimetric planning in stereotactic radiosurgery. (author)

  5. Precision scans of the Pixel cell response of double sided 3D Pixel detectors to pion and X-ray beams

    CERN Document Server

    Mac Raighne, A; Crossley, M; Alianelli, L; Lozano, M; Dumps, R; Fleta, C; Collins, P; Rodrigues, E; Sawhney, K J S; Tlustos, L; Pennicard, D; Buytaert, J; Stewart, G; Parkes, C; Eklund, L; Campbell, M; Marchal, J; Akiba, K; Pellegrini, G; Llopart, X; Plackett, R; Maneuski, D; Gligorov, V V; Tartoni, N; Nicol, M; Bates, R; Gallas, A; Gimenez, E N; van Beuzekom, M; John, M

    2011-01-01

    Three-dimensional (3D) silicon sensors offer potential advantages over standard planar sensors for radiation hardness in future high energy physics experiments and reduced charge-sharing for X-ray applications, but may introduce inefficiencies due to the columnar electrodes. These inefficiencies are probed by studying variations in response across a unit pixel cell in a 55 m m pitch double-sided 3D pixel sensor bump bonded to TimePix and Medipix2 readout ASICs. Two complementary characterisation techniques are discussed: the first uses a custom built telescope and a 120GeV pion beam from the Super Proton Synchrotron (SPS) at CERN; the second employs a novel technique to illuminate the sensor with a micro-focused synchrotron X-ray beam at the Diamond Light Source, UK. For a pion beam incident perpendicular to the sensor plane an overall pixel efficiency of 93.0 +/- 0.5\\% is measured. After a 10 degrees rotation of the device the effect of the columnar region becomes negligible and the overall efficiency rises ...

  6. SU-G-201-08: Energy Response of Thermoluminescent Microcube Dosimeters in Water for Kilovoltage X-Ray Beams

    Energy Technology Data Exchange (ETDEWEB)

    Di Maso, L; Lawless, M; Culberson, W; DeWerd, L [University of Wisconsin- Madison, Madison, WI (United States)

    2016-06-15

    Purpose: To characterize the energy dependence for TLD-100 microcubes in water at kilovoltage energies. Methods: TLD-100 microcubes with dimensions of (1 × 1 × 1) mm{sup 3} were irradiated with kilovoltage x-rays in a custom-built thin-window liquid water phantom. The TLD-100 microcubes were held in Virtual Water™ probes and aligned at a 2 cm depth in water. Irradiations were performed using the M-series x-ray beams of energies ranging from 50-250 kVp and normalized to a {sup 60}Co beam located at the UWADCL. Simulations using the EGSnrc Monte Carlo Code System were performed to model the x-ray beams, the {sup 60}Co beam, the water phantom and the dosimeters in the phantom. The egs-chamber user code was used to tally the dose to the TLDs and the dose to water. The measurements and calculations were used to determine the intrinsic energy dependence, absorbed-dose energy dependence, and absorbed-dose sensitivity. These values were compared to TLD-100 chips with dimensions of (3.2 × 0.9 × 0.9) mm{sup 3}. Results: The measured TLD-100 microcube response per dose to water among all investigated x-ray energies had a maximum percent difference of 61% relative to {sup 60}Co. The simulated ratio of dose to water to the dose to TLD had a maximum percent difference of 29% relative to {sup 60}Co. The ratio of dose to TLD to the TLD output had a maximum percent difference of 13% relative to {sup 60}Co. The maximum percent difference for the absorbed-dose sensitivity was 15% more than the used value of 1.41. Conclusion: These results confirm that differences in beam quality have a significant effect on TLD response when irradiated in water. These results also indicated a difference in TLD-100 response between microcube and chip geometries. The intrinsic energy dependence and the absorbed-dose energy dependence deviated up to 10% between TLD-100 microcubes and chips.

  7. Concept development of X-ray mass thickness detection for irradiated items upon electron beam irradiation processing

    Science.gov (United States)

    Qin, Huaili; Yang, Guang; Kuang, Shan; Wang, Qiang; Liu, Jingjing; Zhang, Xiaomin; Li, Cancan; Han, Zhiwei; Li, Yuanjing

    2018-02-01

    The present project will adopt the principle and technology of X-ray imaging to quickly measure the mass thickness (wherein the mass thickness of the item =density of the item × thickness of the item) of the irradiated items and thus to determine whether the packaging size and inside location of the item will meet the requirements for treating thickness upon electron beam irradiation processing. The development of algorithm of X-ray mass thickness detector as well as the prediction of dose distribution have been completed. The development of the algorithm was based on the X-ray attenuation. 4 standard modules, Al sheet, Al ladders, PMMA sheet and PMMA ladders, were selected for the algorithm development. The algorithm was optimized until the error between tested mass thickness and standard mass thickness was less than 5%. Dose distribution of all energy (1-10 MeV) for each mass thickness was obtained using Monte-carlo method and used for the analysis of dose distribution, which provides the information of whether the item will be penetrated or not, as well as the Max. dose, Min. dose and DUR of the whole item.

  8. Cone-beam X-ray phase-contrast tomography for the observation of single cells in whole organs

    International Nuclear Information System (INIS)

    Krenkel, Martin

    2015-01-01

    X-ray imaging enables the nondestructive investigation of interior structures in otherwise opaque samples. In particular the use of computed tomography (CT) allows for arbitrary virtual slices through the object and 3D information about intricate structures can be obtained. However, when it comes to image very small structures like single cells, the classical CT approach is limited by the weak absorption of soft-tissue. The use of phase information, encoded in measureable intensity images by free-space propagation of coherent X-rays, allows a huge increase in contrast, which enables 3D reconstructions at higher resolutions. In this work the application of propagation-based phase-contrast tomography to lung tissue samples is demonstrated in close to in vivo conditions. Reconstructions of the lung structure of whole mice at down to 5 µm resolution are obtained at a selfbuilt CT setup, which is based on a liquid-metal jet X-ray source. To reach even higher resolutions, synchrotron radiation in combination with suitable holographic phase-retrieval algorithms is employed. Due to optimized cone-beam geometry, field of view and resolution can be varied over a wide range of parameters, so that information on different length scales can be achieved, covering several millimeters field of view down to a 3D resolution of 50 nm. Thus, the sub-cellular 3D imaging of single cells embedded in large pieces of tissue is enabled, which paves the way for future biomedical research.

  9. Towards tabletop production of intense quasimonochromatic X-ray beams using small 2-20 MeV accelerators

    International Nuclear Information System (INIS)

    Avakian, R.O.; Ispirian, K.A.

    2004-01-01

    Full text: The existing synchrotron radiation sources and the fourth generation x-ray sources, which are projected at SLAC, USA, and DESY, Germany, are very expensive. For this reason the search of the novel and cheaper sources using various types of radiation produced by 5-20 MeV electrons available at many hospitals, universities and firms in various countries is of great interest. In this article a review of the physics, history, new theoretical and experimental results and of some applications is given with a purpose to consider the possibilities of construction of small tabletop sources of quasimonochromatic X-ray photon beams necessary for scientific, industrial, medicine and other applications. Simple formulae for almost all types of radiation are given with the help of which one can estimate the expected useful yield and background. PACS: 41.60.-m; 43.35.Ty; 61.85+p;m 78.67.Pt; 78.70.-g. Key words: Bremsstrahlung/Cherenkov radiation/ Transition radiation / Parametric X-ray radiation / Channeling radiation/ Compton scattering

  10. Adaptive x-ray threat detection using sequential hypotheses testing with fan-beam experimental data (Conference Presentation)

    Science.gov (United States)

    Thamvichai, Ratchaneekorn; Huang, Liang-Chih; Ashok, Amit; Gong, Qian; Coccarelli, David; Greenberg, Joel A.; Gehm, Michael E.; Neifeld, Mark A.

    2017-05-01

    We employ an adaptive measurement system, based on sequential hypotheses testing (SHT) framework, for detecting material-based threats using experimental data acquired on an X-ray experimental testbed system. This testbed employs 45-degree fan-beam geometry and 15 views over a 180-degree span to generate energy sensitive X-ray projection data. Using this testbed system, we acquire multiple view projection data for 200 bags. We consider an adaptive measurement design where the X-ray projection measurements are acquired in a sequential manner and the adaptation occurs through the choice of the optimal "next" source/view system parameter. Our analysis of such an adaptive measurement design using the experimental data demonstrates a 3x-7x reduction in the probability of error relative to a static measurement design. Here the static measurement design refers to the operational system baseline that corresponds to a sequential measurement using all the available sources/views. We also show that by using adaptive measurements it is possible to reduce the number of sources/views by nearly 50% compared a system that relies on static measurements.

  11. X-RAY RADIATION MECHANISMS AND BEAMING EFFECT OF HOT SPOTS AND KNOTS IN ACTIVE GALACTIC NUCLEAR JETS

    International Nuclear Information System (INIS)

    Zhang Jin; Bai, J. M.; Chen Liang; Liang Enwei

    2010-01-01

    The observed radio-optical-X-ray spectral energy distributions (SEDs) of 22 hot spots and 45 knots in the jets of 35 active galactic nuclei are complied from the literature and modeled with single-zone lepton models. It is found that the observed luminosities at 5 GHz (L 5 G Hz ) and at 1 keV (L 1 k eV ) are tightly correlated, and the two kinds of sources can be roughly separated with a division of L 1 k eV = L 5 G Hz . Our SED fits show that the mechanisms of the X-rays are diverse. While the X-ray emission of a small fraction of the sources is a simple extrapolation of the synchrotron radiation for the radio-to-optical emission, an inverse Compton (IC) scattering component is necessary to model the X-rays for most of the sources. Considering the sources at rest (the Doppler factor δ = 1), the synchrotron-self-Compton (SSC) scattering would dominate the IC process. This model can interpret the X-rays of some hot spots with a magnetic field strength (B δ= 1 ssc ) being consistent with the equipartition magnetic field (B δ= 1 eq ) in 1 order of magnitude, but an unreasonably low B δ= 1 ssc is required to model the X-rays for all knots. Measuring the deviation between B δ= 1 ssc and B δ= 1 eq with ratio R B ≡ B δ= 1 eq /B δ= 1 ssc , we find that R B is greater than 1 and it is tightly anti-correlated with ratio R L ≡ L 1 k eV /L 5 G Hz for both the knots and the hot spots. We propose that the deviation may be due to the neglect of the relativistic bulk motion for these sources. Considering this effect, the IC/cosmic microwave background (CMB) component would dominate the IC process. We show that the IC/CMB model well explains the X-ray emission for most sources under the equipartition condition. Although the derived beaming factor (δ) and co-moving equipartition magnetic field (B' eq ) of some hot spots are comparable to the knots, the δ values of the hot spots tend to be smaller and their B' eq values tend to be larger than that of the knots, favoring

  12. Patient dose simulations for scanning-beam digital x-ray tomosynthesis of the lungs

    International Nuclear Information System (INIS)

    Nelson, Geoff; Fahrig, Rebecca; Yoon, Sungwon; Krishna, Ganesh; Wilfley, Brian

    2013-01-01

    location. When tumor SNR is held constant (i.e., x-ray fluence is scaled appropriately), SBDX gives 2–10 times less dose than fluoroscopy for the same conditions within the typical range of patient locations. The relative position of the patient (as a percent of SDD) has a much more significant impact on dose than either SDD or patient position. The patient position providing the minimum dose for a given tumor SNR and SDD is approximately the same as the position of maximum tomographic angle.Conclusions: SBDX offers a significant dose advantage over currently used C-arm fluoroscopy. The patient location with lowest dose coincides with the location of maximum tomographic angle. In order to provide adequate space for the patient and for the pulmonologists’ equipment, a SDD of 100 cm is recommended

  13. Patient dose simulations for scanning-beam digital x-ray tomosynthesis of the lungs

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, Geoff; Fahrig, Rebecca [Department of Radiology, Stanford University, Stanford, California 94305 (United States); Yoon, Sungwon [Varian Medical Systems, Palo Alto, California 94304 (United States); Krishna, Ganesh [Palo Alto Medical Foundation, Mountain View, California 94040 (United States); Wilfley, Brian [Triple Ring Technologies, Inc., Newark, California 94560 (United States)

    2013-11-15

    location. When tumor SNR is held constant (i.e., x-ray fluence is scaled appropriately), SBDX gives 2–10 times less dose than fluoroscopy for the same conditions within the typical range of patient locations. The relative position of the patient (as a percent of SDD) has a much more significant impact on dose than either SDD or patient position. The patient position providing the minimum dose for a given tumor SNR and SDD is approximately the same as the position of maximum tomographic angle.Conclusions: SBDX offers a significant dose advantage over currently used C-arm fluoroscopy. The patient location with lowest dose coincides with the location of maximum tomographic angle. In order to provide adequate space for the patient and for the pulmonologists’ equipment, a SDD of 100 cm is recommended.

  14. X-ray Microprobe for Fluorescence and Diffraction Analysis

    International Nuclear Information System (INIS)

    Ice, G.E.

    2005-01-01

    X-ray diffraction (see unit 1.1) and x-ray excited fluorescence analysis are powerful techniques for the nondestructive measurement of crystal structure and chemical composition. X-ray fluorescence analysis is inherently nondestructive with orders of magnitude lower power deposited for the same detectable limit as with fluorescence excited by charged particle probes (Sparks, 1980). X-ray diffraction analysis is sensitive to crystal structure with orders-of-magnitude greater sensitivity to crystallographic strain than electron probes (Rebonato, et al. 1989). When a small-area x-ray microbeam is used as the probe, chemical composition (Z>14), crystal structure, crystalline texture, and crystalline strain distributions can be determined. These distributions can be studied both at the surface of the sample and deep within the sample (Fig. 1). Current state-of-the-art can achieve an ∼1 mm-D x-ray microprobe and an ∼0.1 mm-D x-ray microprobe has been demonstrated (Bilderback, et al., 1994). Despite their great chemical and crystallographic sensitivities, x-ray microprobe techniques have until recently been restricted by inefficient x-ray focusing optics and weak x-ray sources; x-ray microbeam analysis was largely superseded by electron techniques in the 50's. However, interest in x-ray microprobe techniques has now been revived (Howells, et al., 1983; Ice and Sparks, 1984; Chevallier, et al., 1997; Riekel 1992; Thompson, el al., 1992; and Making and Using... 1997) by the development of efficient x-ray focusing optics and ultra-high intensity synchrotron x-ray sources (Buras and Tazzari, 1984; Shenoy, et al., 1988). These advances have increased the achievable microbeam flux by more than 11 orders of magnitude (Fig. 2) (Ice, 1997); the flux in a tunable 1 mm-D beam on a 'so called' 3rd-generation synchrotron source such as the APS can exceed the flux in a fixed-energy mm2 beam on a conventional source. These advances make x-ray microfluorescence and x-ray

  15. Dose and energy dependence of response of Gafchromic XR-QA film for kilovoltage x-ray beams.

    Science.gov (United States)

    Rampado, O; Garelli, E; Deagostini, S; Ropolo, R

    2006-06-07

    There is a growing interest in Gafchromic films for patient dosimetry in radiotherapy and in radiology. A new model (XR-QA) with high sensitivity to low dose was tested in this study. The response of the film to different x-ray beam energies (range 28-145 kVp with various filtrations, dose range 0-100 mGy) and to visible light was investigated, together with the after exposure darkening properties. Exposed films were digitized with a commercially available, optical flatbed scanner. A single functional form for dose versus net pixel value variation has been determined for all the obtained calibration curves, with a unique fit parameter different for each of the used x-ray beams. The film response was dependent on beam energy, with higher colour variations for the beams in the range 80-140 kVp. Different sources of uncertainties in dose measurements, governed by the digitalization process, the film response uniformity and the calibration curve fit procedure, have been considered. The overall one-sigma dose measurement uncertainty depended on the beam energy and decreased with increasing absorbed dose. For doses above 10 mGy and beam energies in the range 80-140 kVp the total uncertainty was less than 5%, whereas for the 28 kVp beam the total uncertainty at 10 mGy was about 10%. The post-exposure colour variation was not negligible in the first 24 h after the exposure, with a consequent increase in the calculated dose of about 10%. Results of the analysis of the sensitivity to visible light indicated that a short exposure of this film to ambient and scanner light during the measurements will not have a significant impact on the radiation dosimetry.

  16. Dose and energy dependence of response of Gafchromic (registered) XR-QA film for kilovoltage x-ray beams

    Energy Technology Data Exchange (ETDEWEB)

    Rampado, O; Garelli, E; Deagostini, S; Ropolo, R [Struttura Complessa fisica Sanitaria, Azienda Ospedaliera San Giovanni Battista, Corso Bramante 88, 10126 Turin (Italy)

    2006-06-07

    There is a growing interest in Gafchromic (registered) films for patient dosimetry in radiotherapy and in radiology. A new model (XR-QA) with high sensitivity to low dose was tested in this study. The response of the film to different x-ray beam energies (range 28-145 kVp with various filtrations, dose range 0-100 mGy) and to visible light was investigated, together with the after exposure darkening properties. Exposed films were digitized with a commercially available, optical flatbed scanner. A single functional form for dose versus net pixel value variation has been determined for all the obtained calibration curves, with a unique fit parameter different for each of the used x-ray beams. The film response was dependent on beam energy, with higher colour variations for the beams in the range 80-140 kVp. Different sources of uncertainties in dose measurements, governed by the digitalization process, the film response uniformity and the calibration curve fit procedure, have been considered. The overall one-sigma dose measurement uncertainty depended on the beam energy and decreased with increasing absorbed dose. For doses above 10 mGy and beam energies in the range 80-140 kVp the total uncertainty was less than 5%, whereas for the 28 kVp beam the total uncertainty at 10 mGy was about 10%. The post-exposure colour variation was not negligible in the first 24 h after the exposure, with a consequent increase in the calculated dose of about 10%. Results of the analysis of the sensitivity to visible light indicated that a short exposure of this film to ambient and scanner light during the measurements will not have a significant impact on the radiation dosimetry.

  17. Simbol-X Hard X-ray Focusing Mirrors: Results Obtained During the Phase A Study

    International Nuclear Information System (INIS)

    Tagliaferri, G.; Basso, S.; Civitani, M.; Conconi, P.; Cotroneo, V.; Pareschi, G.; Spiga, D.; Borghi, G.; Garoli, D.; Mattarello, V.; Orlandi, A.; Valsecchi, G.; Vernani, D.; Burkert, W.; Freyberg, M.; Hartner, G.; Citterio, O.; Gorenstein, P.; Romaine, S.

    2009-01-01

    Simbol-X will push grazing incidence imaging up to 80 keV, providing a strong improvement both in sensitivity and angular resolution compared to all instruments that have operated so far above 10 keV. The superb hard X-ray imaging capability will be guaranteed by a mirror module of 100 electroformed Nickel shells with a multilayer reflecting coating. Here we will describe the technogical development and solutions adopted for the fabrication of the mirror module, that must guarantee an Half Energy Width (HEW) better than 20 arcsec from 0.5 up to 30 keV and a goal of 40 arcsec at 60 keV. During the phase A, terminated at the end of 2008, we have developed three engineering models with two, two and three shells, respectively. The most critical aspects in the development of the Simbol-X mirrors are i) the production of the 100 mandrels with very good surface quality within the timeline of the mission, ii) the replication of shells that must be very thin (a factor of 2 thinner than those of XMM-Newton) and still have very good image quality up to 80 keV, iii) the development of an integration process that allows us to integrate these very thin mirrors maintaining their intrinsic good image quality. The Phase A study has shown that we can fabricate the mandrels with the needed quality and that we have developed a valid integration process. The shells that we have produced so far have a quite good image quality, e.g. HEW < or approx. 30 arcsec at 30 keV, and effective area. However, we still need to make some improvements to reach the requirements. We will briefly present these results and discuss the possible improvements that we will investigate during phase B.

  18. Simbol-X Hard X-ray Focusing Mirrors: Results Obtained During the Phase A Study

    Science.gov (United States)

    Tagliaferri, G.; Basso, S.; Borghi, G.; Burkert, W.; Citterio, O.; Civitani, M.; Conconi, P.; Cotroneo, V.; Freyberg, M.; Garoli, D.; Gorenstein, P.; Hartner, G.; Mattarello, V.; Orlandi, A.; Pareschi, G.; Romaine, S.; Spiga, D.; Valsecchi, G.; Vernani, D.

    2009-05-01

    Simbol-X will push grazing incidence imaging up to 80 keV, providing a strong improvement both in sensitivity and angular resolution compared to all instruments that have operated so far above 10 keV. The superb hard X-ray imaging capability will be guaranteed by a mirror module of 100 electroformed Nickel shells with a multilayer reflecting coating. Here we will describe the technogical development and solutions adopted for the fabrication of the mirror module, that must guarantee an Half Energy Width (HEW) better than 20 arcsec from 0.5 up to 30 keV and a goal of 40 arcsec at 60 keV. During the phase A, terminated at the end of 2008, we have developed three engineering models with two, two and three shells, respectively. The most critical aspects in the development of the Simbol-X mirrors are i) the production of the 100 mandrels with very good surface quality within the timeline of the mission, ii) the replication of shells that must be very thin (a factor of 2 thinner than those of XMM-Newton) and still have very good image quality up to 80 keV, iii) the development of an integration process that allows us to integrate these very thin mirrors maintaining their intrinsic good image quality. The Phase A study has shown that we can fabricate the mandrels with the needed quality and that we have developed a valid integration process. The shells that we have produced so far have a quite good image quality, e.g. HEW <~30 arcsec at 30 keV, and effective area. However, we still need to make some improvements to reach the requirements. We will briefly present these results and discuss the possible improvements that we will investigate during phase B.

  19. SU-E-I-52: Effect of Various X-Ray Beam Qualities On the Exposure Index

    International Nuclear Information System (INIS)

    Yasumatsu, S; Iwase, K; Shimizu, Y; Tanaka, N; Morishita, J

    2015-01-01

    Purpose: The exposure index (EI) proposed by the International Electrotechnical Commission (IEC) 62494-1 is expected to be utilized as a standard dose index by every manufacturer. The IEC recommended the usage of RQA5 for the EI. However, X-ray beam qualities, particularly in clinical practices, vary depending on the examination objects and exposure conditions, including usage of anti-scatter grids. We investigated the effects of the X-ray beam qualities other than RQA5 on the EI. Methods: The Xray beam qualities of RQA3, 5, 7, and 9 in IEC 61267 Ed. 1.0 were adopted in a computed radiography system. A uniform exposure without objects was performed to measure the exposure indicators (S values) and air kerma (K). The relational equations between the S values and K were derived for the determination of the EI values. The EI values for RQA3, 7, and 9 were compared to those for RQA5 at the fixed S values of 100, 200, 400, and 600. Finally, the half-value layers (HVLs) using four grids (ratio 6:1, 8:1, 10:1, and 12:1) for the RQA5 X-ray were compared to those with RQA3–9. Results: The EI values for RQA3, 7, and 9 were up to 35.3%, 11.8%, and 38.7% higher, respectively, than that for RQA5 at the S value of 600. The HVLs without grids and with various grids for RQA5 were 6.85 mm Al. and in the range of 6.94–7.29 mm Al. (ΔHVL: up to 0.44 mm Al.), respectively. This variation in the HVLs with grids was smaller than that observed for RQA3–9 (ΔHVL: 2.0–7.5 mm Al.). Conclusion: Although the usage of grids may not greatly affect the EI, the X-ray beam quality for the determination of the EI cannot be ignored in the clinical evaluation of the dose index

  20. Oxidation of nanostructured Ti films produced by low energy cluster beam deposition: An X-ray Photoelectron Spectroscopy characterization

    International Nuclear Information System (INIS)

    Simone, Monica de; Snidero, Elena; Coreno, Marcello; Bongiorno, Gero; Giorgetti, Luca; Amati, Matteo; Cepek, Cinzia

    2012-01-01

    We used in-situ X-ray Photoelectron Spectroscopy (XPS) to study the oxidation process of a cluster-assembled metallic titanium film exposed to molecular oxygen at room temperature. The nanostructured film has been grown on a Si(111) substrate, in ultra high vacuum conditions, by coupling a supersonic cluster beam deposition system with an XPS experimental chamber. Our results show that upon in-situ oxygen exposure Ti 3+ is the first oxidation state observed, followed by Ti 4+ , whereas Ti 2+ is practically absent during the whole process. Our results compare well with the existing literature on Ti films produced using other techniques.