Production of High Harmonic X-Ray Radiation from Non-linear Thomson at LLNL PLEIADES

CERN Document Server

Lim, Jae; Betts, Shawn; Crane, John; Doyuran, Adnan; Frigola, Pedro; Gibson, David J; Hartemann, Fred V; Rosenzweig, James E; Travish, Gil; Tremaine, Aaron M

2005-01-01

We describe an experiment for production of high harmonic x-ray radiation from Thomson backscattering of an ultra-short high power density laser by a relativistic electron beam at the PLEIADES facility at LLNL. In this scenario, electrons execute a “figure-8” motion under the influence of the high-intensity laser field, where the constant characterizing the field strength is expected to exceed unity: $aL=e*EL/m*c*ωL ≥ 1$. With large $aL$ this motion produces high harmonic x-ray radiation and significant broadening of the spectral peaks. This paper is intended to give a layout of the PLEIADES experiment, along with progress towards experimental goals.

X-ray Thomson Scattering from Spherically Imploded ICF Ablators

Science.gov (United States)

Kritcher, Andrea; Doeppner, Tilo; Landen, Otto; Glenzer, Siegfried

2010-11-01

Time-resolved X-ray Thomson scattering measurements from spherically imploded inertial fusion capsules-type targets have been obtained for the first time at the Omega OMEGA laser facility to characterize the in-flight properties of ICF ablators. In these experiments, the non-collective, or microscopic particle behavior, of imploding CH and Be shells, was probed using a 9 keV Zn He-alpha x-ray source at scattering angles of 113^o and 135^o. for two drive pulse shapes.As an example, the analysis of In-flight scattering measurements from one set of directly-driven compressed 8600 μm-diameter, 40-μm thick Be shells taken (4.2 ns after the start of the compression beamswhen compressed a factor of 4.83x) yielded electron densities of ˜ 1.2±0.23x10^24cm-3, temperatures of ˜13±32 eV, and an ionization state of Be(+2), with uncertainties in the temperature and density of about 40% and 20%. These conditions resulting in an inferred adiabat (ratio of plasma pressure to Fermi degenerate pressure) of 1.797 +0.3/-.5 with an error of about 30%. The high signal-to-noise and high signal-to-background ratio of data obtained in these experiments provides a platform for studying the adiabat of other indirect-drive ICF ablators such as CH and High Density Carbon (HDC) ablators and demonstrates the viability of using this diagnostic to study the in-flight properties adiabat of implosion targets at the National Ignition Facility (NIF).

Production of High Harmonic X-ray Radiation from Non-linear Thomson Scattering at LLNL PLEIADES

International Nuclear Information System (INIS)

Lim, J; Doyuran, A; Frigola, P; Travish, G; Rosenzweig, J; Anderson, S; Betts, S; Crane, J; Gibson, D; Hartemann, F; Tremaine, A

2005-01-01

We describe an experiment for production of high harmonic x-ray radiation from Thomson backscattering of an ultra-short high power density laser by a relativistic electron beam at the PLEIADES facility at LLNL. In this scenario, electrons execute a ''figure-8'' motion under the influence of the high-intensity laser field, where the constant characterizing the field strength is expected to exceed unity: a L = eE L /m e cw L (ge) 1. With large a L this motion produces high harmonic x-ray radiation and significant broadening of the spectral peaks. This paper is intended to give a layout of the PLEIADES experiment, along with progress towards experimental goals

Evaluation of the soft x-ray reflectivity of micropore optics using anisotropic wet etching of silicon wafers.

Science.gov (United States)

Mitsuishi, Ikuyuki; Ezoe, Yuichiro; Koshiishi, Masaki; Mita, Makoto; Maeda, Yoshitomo; Yamasaki, Noriko Y; Mitsuda, Kazuhisa; Shirata, Takayuki; Hayashi, Takayuki; Takano, Takayuki; Maeda, Ryutaro

2010-02-20

The x-ray reflectivity of an ultralightweight and low-cost x-ray optic using anisotropic wet etching of Si (110) wafers is evaluated at two energies, C K(alpha)0.28 keV and Al K(alpha)1.49 keV. The obtained reflectivities at both energies are not represented by a simple planar mirror model considering surface roughness. Hence, an geometrical occultation effect due to step structures upon the etched mirror surface is taken into account. Then, the reflectivities are represented by the theoretical model. The estimated surface roughness at C K(alpha) (approximately 6 nm rms) is significantly larger than approximately 1 nm at Al K(alpha). This can be explained by different coherent lengths at two energies.

Evaluation of the soft x-ray reflectivity of micropore optics using anisotropic wet etching of silicon wafers

Energy Technology Data Exchange (ETDEWEB)

Mitsuishi, Ikuyuki; Ezoe, Yuichiro; Koshiishi, Masaki; Mita, Makoto; Maeda, Yoshitomo; Yamasaki, Noriko Y.; Mitsuda, Kazuhisa; Shirata, Takayuki; Hayashi, Takayuki; Takano, Takayuki; Maeda, Ryutaro

2010-02-20

The x-ray reflectivity of an ultralightweight and low-cost x-ray optic using anisotropic wet etching of Si (110) wafers is evaluated at two energies, C K{alpha}0.28 keV and Al K{alpha}1.49 keV. The obtained reflectivities at both energies are not represented by a simple planar mirror model considering surface roughness. Hence, an geometrical occultation effect due to step structures upon the etched mirror surface is taken into account. Then, the reflectivities are represented by the theoretical model. The estimated surface roughness at C K{alpha} ({approx}6 nm rms) is significantly larger than {approx}1 nm at Al K{alpha}. This can be explained by different coherent lengths at two energies.

X-Ray Thomson Scattering Without the Chihara Decomposition

Science.gov (United States)

Magyar, Rudolph; Baczewski, Andrew; Shulenburger, Luke; Hansen, Stephanie B.; Desjarlais, Michael P.; Sandia National Laboratories Collaboration

X-Ray Thomson Scattering is an important experimental technique used in dynamic compression experiments to measure the properties of warm dense matter. The fundamental property probed in these experiments is the electronic dynamic structure factor that is typically modeled using an empirical three-term decomposition (Chihara, J. Phys. F, 1987). One of the crucial assumptions of this decomposition is that the system's electrons can be either classified as bound to ions or free. This decomposition may not be accurate for materials in the warm dense regime. We present unambiguous first principles calculations of the dynamic structure factor independent of the Chihara decomposition that can be used to benchmark these assumptions. Results are generated using a finite-temperature real-time time-dependent density functional theory applied for the first time in these conditions. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Security Administration under contract DE-AC04-94AL85000.

Design calculations for a xenon plasma x-ray shield to protect the NIF optical Thomson scattering diagnostic.

Science.gov (United States)

Swadling, G F; Ross, J S; Datte, P; Moody, J; Divol, L; Jones, O; Landen, O

2016-11-01

An Optical Thomson Scattering (OTS) diagnostic is currently being developed for the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory. This diagnostic is designed to make measurements of the hohlraum plasma parameters, such as the electron temperature and the density, during inertial confinement fusion (ICF) experiments. NIF ICF experiments present a very challenging environment for optical measurements; by their very nature, hohlraums produce intense soft x-ray emission, which can cause "blanking" (radiation induced opacity) of the radiation facing optical components. The soft x-ray fluence at the surface of the OTS blast shield, 60 cm from the hohlraum, is estimated to be ∼8 J cm -2 . This is significantly above the expected threshold for the onset of "blanking" effects. A novel xenon plasma x-ray shield is proposed to protect the blast shield from x-rays and mitigate "blanking." Estimates suggest that an areal density of 10 19 cm -2 Xe atoms will be sufficient to absorb 99.5% of the soft x-ray flux. Two potential designs for this shield are presented.

Using X-ray Thomson Scattering to Characterize Highly Compressed, Near-Degenerate Plasmas at the NIF

Science.gov (United States)

Doeppner, Tilo; Kraus, D.; Neumayer, P.; Bachmann, B.; Divol, L.; Kritcher, A. L.; Landen, O. L.; Fletcher, L.; Glenzer, S. H.; Falcone, R. W.; MacDonald, M. J.; Saunders, A.; Witte, B.; Redmer, R.; Chapman, D.; Baggott, R.; Gericke, D. O.; Yi, S. A.

2017-10-01

We are developing x-ray Thomson scattering for implosion experiments at the National Ignition Facility to characterize plasma conditions in plastic and beryllium capsules near stagnation, reaching more than 20x compression and electron densities of 1025 cm-3, corresponding to a Fermi energy of 170 eV. Using a zinc He- α x-ray source at 9 keV, experiments at a large scattering angle of 120° measure non-collective scattering spectra with high sensitivity to K-shell ionization, and find higher charge states than predicted by widely used ionization models. Reducing the scattering angle to 30° probes the collective scattering regime with sensitivity to collisions and conductivity. We will discuss recent results and future plans. This work was performed under the auspices of the US Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

Analysis and implementation of a space resolving spherical crystal spectrometer for x-ray Thomson scattering experiments.

Science.gov (United States)

Harding, E C; Ao, T; Bailey, J E; Loisel, G; Sinars, D B; Geissel, M; Rochau, G A; Smith, I C

2015-04-01

The application of a space-resolving spectrometer to X-ray Thomson Scattering (XRTS) experiments has the potential to advance the study of warm dense matter. This has motivated the design of a spherical crystal spectrometer, which is a doubly focusing geometry with an overall high sensitivity and the capability of providing high-resolution, space-resolved spectra. A detailed analysis of the image fluence and crystal throughput in this geometry is carried out and analytical estimates of these quantities are presented. This analysis informed the design of a new spectrometer intended for future XRTS experiments on the Z-machine. The new spectrometer collects 6 keV x-rays with a spherically bent Ge (422) crystal and focuses the collected x-rays onto the Rowland circle. The spectrometer was built and then tested with a foam target. The resulting high-quality spectra prove that a spherical spectrometer is a viable diagnostic for XRTS experiments.

High Brightness, Laser-Driven X-ray Source for Nanoscale Metrology and Femtosecond Dynamics

Energy Technology Data Exchange (ETDEWEB)

Siders, C W; Crane, J K; Semenov, V; Betts, S; Kozioziemski, B; Wharton, K; Wilks, S; Barbee, T; Stuart, B; Kim, D E; An, J; Barty, C

2007-02-26

This project developed and demonstrated a new, bright, ultrafast x-ray source based upon laser-driven K-alpha generation, which can produce an x-ray flux 10 to 100 times greater than current microfocus x-ray tubes. The short-pulse (sub-picosecond) duration of this x-ray source also makes it ideal for observing time-resolved dynamics of atomic motion in solids and thin films.

X rays and condensed matter

International Nuclear Information System (INIS)

Daillant, J.

1997-01-01

After a historical review of the discovery and study of X rays, the various interaction processes between X rays and matter are described: Thomson scattering, Compton scattering, X-photon absorption through photoelectric effect, and magnetic scattering. X ray sources such as the European Synchrotron Radiation Facility (ESRF) are described. The various X-ray applications are presented: imagery such as X tomography, X microscopy, phase contrast; X-ray photoelectron spectroscopy and X-ray absorption spectroscopy; X-ray scattering and diffraction techniques

Design calculations for a xenon plasma x-ray shield to protect the NIF optical Thomson scattering diagnostic

Energy Technology Data Exchange (ETDEWEB)

Swadling, G. F.; Ross, J. S.; Datte, P.; Moody, J.; Divol, L.; Jones, O.; Landen, O. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

2016-11-15

An Optical Thomson Scattering (OTS) diagnostic is currently being developed for the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory. This diagnostic is designed to make measurements of the hohlraum plasma parameters, such as the electron temperature and the density, during inertial confinement fusion (ICF) experiments. NIF ICF experiments present a very challenging environment for optical measurements; by their very nature, hohlraums produce intense soft x-ray emission, which can cause “blanking” (radiation induced opacity) of the radiation facing optical components. The soft x-ray fluence at the surface of the OTS blast shield, 60 cm from the hohlraum, is estimated to be ∼8 J cm{sup −2}. This is significantly above the expected threshold for the onset of “blanking” effects. A novel xenon plasma x-ray shield is proposed to protect the blast shield from x-rays and mitigate “blanking.” Estimates suggest that an areal density of 10{sup 19} cm{sup −2} Xe atoms will be sufficient to absorb 99.5% of the soft x-ray flux. Two potential designs for this shield are presented.

X-ray state analysis by means of electron capture decay

Energy Technology Data Exchange (ETDEWEB)

Tamaki, Yoichi [Miyagi Univ. of Education, Sendai (Japan)

1998-01-01

K{alpha} X-ray induced by EC decay of {sup 55}Fe and {sup 71}Ge-labeled compounds were measured by wavelength dispersive X-ray spectrometer equipped position sensitive proportional detector. In both nuclides, peak energies of K{alpha}{sub 2} X-rays are lower (-0.4 - -0.6 eV) than those of Mn and Ga compounds by photoionization. It is thought that the causes of these differences are intensity of high energy satellite peaks by shake up process. (author)

Improving a high-efficiency, gated spectrometer for x-ray Thomson scattering experiments at the National Ignition Facility

Energy Technology Data Exchange (ETDEWEB)

Döppner, T., E-mail: doeppner1@llnl.gov; Bachmann, B.; Emig, J.; Hardy, M.; Kalantar, D. H.; Kritcher, A. L.; Landen, O. L.; Ma, T.; Wood, R. D. [Lawrence Livermore National Laboratory, Livermore, California 94720 (United States); Kraus, D.; Saunders, A. M. [University of California, Berkeley, California 94720 (United States); Neumayer, P. [Gesellschaft für Schwerionenphysik, Darmstadt (Germany); Falcone, R. W. [University of California, Berkeley, California 94720 (United States); Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Fletcher, L. B. [SLAC National Accelerator Laboratory, Menlo Park, California 94720 (United States)

2016-11-15

We are developing x-ray Thomson scattering for applications in implosion experiments at the National Ignition Facility. In particular we have designed and fielded MACS, a high-efficiency, gated x-ray spectrometer at 7.5–10 keV [T. Döppner et al., Rev. Sci. Instrum. 85, 11D617 (2014)]. Here we report on two new Bragg crystals based on Highly Oriented Pyrolytic Graphite (HOPG), a flat crystal and a dual-section cylindrically curved crystal. We have performed in situ calibration measurements using a brass foil target, and we used the flat HOPG crystal to measure Mo K-shell emission at 18 keV in 2nd order diffraction. Such high photon energy line emission will be required to penetrate and probe ultra-high-density plasmas or plasmas of mid-Z elements.

Characteristics of a molybdenum X-pinch X-ray source as a probe source for X-ray diffraction studies

International Nuclear Information System (INIS)

Zucchini, F.; Chauvin, C.; Combes, P.; Sol, D.; Loyen, A.; Roques, B.; Grunenwald, J.; Bland, S. N.

2015-01-01

X-ray emission from a molybdenum X-pinch has been investigated as a potential probe for the high pressure states made in dynamic compression experiments. Studies were performed on a novel 300 kA, 400 ns generator which coupled the load directly to a low inductance capacitor and switch combination. The X-pinch load consisted of 4 crossed molybdenum wires of 13 μm diameter, crossed at an angle of 62°. The load height was 10 mm. An initial x-ray burst generated at the wire crossing point, radiated in the soft x-ray range (hυ < 10 keV). This was followed, 2–5 ns later, by at least one harder x-ray burst (hυ > 10 keV) whose power ranged from 1 to 7 MW. Time integrated spectral measurements showed that the harder bursts were dominated by K-alpha emission; though, a lower level, wide band continuum up to at least 30 keV was also present. Initial tests demonstrated that the source was capable of driving Laue diffraction experiments, probing uncompressed samples of LiF and aluminium

Generation of Attosecond x-ray pulse using Coherent Relativistic Nonlinear Thomson Scattering

Energy Technology Data Exchange (ETDEWEB)

Lee, Ki Tae; Park, Seong Hee; Cha, Yong Ho; Jeong, Young Uk; Lee, Byung Cheol [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2005-07-01

Relativistic plasma, a new regime in physics, has been opened due to the development in ultra-intense laser technology during the past decade. Not only the fundamental aspect of relativistic plasma are attractive but also its potential application seems to be significant especially in the area of the generation of high energy particles such as electrons, ions, positrons, and {gamma}-rays. The generation of x-ray radiation with a pulse width of sub-femtoseconds presently draws much attention because such a radiation allows one to explore ultra-fast dynamics of electrons and nucleons. Several schemes have been proposed and/or demonstrated to generate an ultra-short x-ray pulse: the relativistic Doppler shift of a backscattered laser pulse by a relativistic electron beam, the harmonic frequency upshift of a laser pulse by relativistic nonlinear motion of electrons, high order harmonic generation in the interaction of intense laser pulse with noble gases and solids The train of a few 100 attosecond pulses has been observed in the case of laser-noble gas interaction. When a low-intensity laser pulse is irradiated on an electron, the electron undergoes a harmonic oscillatory motion and generates a dipole radiation with the same frequency as the incident laser pulse, which is called Thomson scattering. As the laser intensity increases, the oscillatory motion of the electron becomes relativistically nonlinear, which leads to the generation of harmonic radiations, referred to as Relativistic Nonlinear Thomson Scattered (RNTS) radiation. The motion of the electron begins to be relativistic as the following normalized vector potential approaches to unity: a{sub 0}=8.5 x 10{sup -10} {lambda}{iota}{sup 1/2} , (1) where {lambda} is the laser wavelength in {mu}m and I the laser intensity in W/cm{sup 2} The RNTS radiation has been investigated in analytical ways. Recently, indebted to the development of the ultra-intense laser pulse, experiments on RNTS radiation have been carried

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

Energy Technology Data Exchange (ETDEWEB)

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

2014-11-15

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

Measurement of high-dynamic range x-ray Thomson scattering spectra for the characterization of nano-plasmas at LCLS

Energy Technology Data Exchange (ETDEWEB)

MacDonald, M. J., E-mail: macdonm@umich.edu [University of Michigan, Ann Arbor, Michigan 48109 (United States); SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Gorkhover, T. [SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Technische Universität, 10623 Berlin (Germany); Bachmann, B.; Hau-Riege, S. P.; Pardini, T.; Döppner, T. [Lawrence Livermore National Laboratory, Livermore, California 94551 (United States); Bucher, M. [SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Argonne National Lab, Lemont, Illinois 60439 (United States); Carron, S. [California Lutheran University, Thousand Oaks, California 91360 (United States); Coffee, R. N.; Fletcher, L. B.; Gamboa, E. J.; Glenzer, S. H.; Göde, S.; Krzywinski, J.; O’Grady, C. P.; Osipov, T.; Swiggers, M. [SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Drake, R. P. [University of Michigan, Ann Arbor, Michigan 48109 (United States); Ferguson, K. R. [SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Stanford University, Stanford, California 94305 (United States); Kraus, D. [University of California, Berkeley, California 94720 (United States); and others

2016-11-15

Atomic clusters can serve as ideal model systems for exploring ultrafast (∼100 fs) laser-driven ionization dynamics of dense matter on the nanometer scale. Resonant absorption of optical laser pulses enables heating to temperatures on the order of 1 keV at near solid density conditions. To date, direct probing of transient states of such nano-plasmas was limited to coherent x-ray imaging. Here we present the first measurement of spectrally resolved incoherent x-ray scattering from clusters, enabling measurements of transient temperature, densities, and ionization. Single shot x-ray Thomson scattering signals were recorded at 120 Hz using a crystal spectrometer in combination with a single-photon counting and energy-dispersive pnCCD. A precise pump laser collimation scheme enabled recording near background-free scattering spectra from Ar clusters with an unprecedented dynamic range of more than 3 orders of magnitude. Such measurements are important for understanding collective effects in laser-matter interactions on femtosecond time scales, opening new routes for the development of schemes for their ultrafast control.

The SPARC-LAB Thomson source

International Nuclear Information System (INIS)

Vaccarezza, C.; Alesini, D.; Anania, M.P.; Bacci, A.; Biagioni, A.; Bisesto, F.; Bellaveglia, M.; Cardarelli, P.; Cardelli, F.; Cianchi, A.; Chiadroni, E.; Croia, M.; Curcio, A.; Delogu, P.; Giovenale, D. Di; Domenico, G. Di; Pirro, G. Di; Drebot, I.; Ferrario, M.; Filippi, F.

2016-01-01

The SPARC-LAB Thomson source is a compact X-ray source based on the Thomson backscattering process presently under its second phase of commissioning at the LNF. The electron beam energy ranges between 30 and 150 MeV, the electrons collide head-on with the Ti:Sapphire FLAME laser pulse the energy of which ranges between 1 and 5 J with pulse lengths in the 25 fs–10 ps range, this provides an X-ray energy tunability in the range of 20–500 keV, with the further capability to generate strongly non-linear phenomena and to drive diffusion processes due to multiple and plural scattering effects. The experimental results of the obtained X-ray radiation are presented.

The SPARC-LAB Thomson source

Energy Technology Data Exchange (ETDEWEB)

Vaccarezza, C., E-mail: cristina.vaccarezza@lnf.infn.it [INFN-LNF, Via Enrico Fermi, 40 00044 Frascati, Rome (Italy); Alesini, D.; Anania, M.P. [INFN-LNF, Via Enrico Fermi, 40 00044 Frascati, Rome (Italy); Bacci, A. [INFN-MI, Via Celoria 16, 20133 Milan (Italy); Biagioni, A.; Bisesto, F.; Bellaveglia, M. [INFN-LNF, Via Enrico Fermi, 40 00044 Frascati, Rome (Italy); Cardarelli, P. [University of Ferrara and INFN-FE, via Saragat 1, 44122 Ferrara (Italy); Cardelli, F. [University La Sapienza and INFN-Roma1, Piazzale Aldo Moro, 2 00161 Rome (Italy); Cianchi, A. [University of Rome Tor Vergata, Via della Ricerca Scientifica 1, 00133 Rome (Italy); Chiadroni, E.; Croia, M.; Curcio, A. [INFN-LNF, Via Enrico Fermi, 40 00044 Frascati, Rome (Italy); Delogu, P. [University of Pisa and INFN-PI, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Giovenale, D. Di [INFN-LNF, Via Enrico Fermi, 40 00044 Frascati, Rome (Italy); Domenico, G. Di [University of Ferrara and INFN-FE, via Saragat 1, 44122 Ferrara (Italy); Pirro, G. Di [INFN-LNF, Via Enrico Fermi, 40 00044 Frascati, Rome (Italy); Drebot, I. [INFN-MI, Via Celoria 16, 20133 Milan (Italy); Ferrario, M. [INFN-LNF, Via Enrico Fermi, 40 00044 Frascati, Rome (Italy); Filippi, F. [University La Sapienza and INFN-Roma1, Piazzale Aldo Moro, 2 00161 Rome (Italy); and others

2016-09-01

The SPARC-LAB Thomson source is a compact X-ray source based on the Thomson backscattering process presently under its second phase of commissioning at the LNF. The electron beam energy ranges between 30 and 150 MeV, the electrons collide head-on with the Ti:Sapphire FLAME laser pulse the energy of which ranges between 1 and 5 J with pulse lengths in the 25 fs–10 ps range, this provides an X-ray energy tunability in the range of 20–500 keV, with the further capability to generate strongly non-linear phenomena and to drive diffusion processes due to multiple and plural scattering effects. The experimental results of the obtained X-ray radiation are presented.

Spectral and imaging characterization of tabletop X-ray lasers

Energy Technology Data Exchange (ETDEWEB)

Dunn, J.; Osterheld, A.L.; Moon, S.J.; Fournier, K.B.; Nilsen, J. [Lawrence Livermore National Lab., CA (United States); Faenov, A.Ya.; Pikuz, T.A.; Skobelev, I.Yu.; Magunov, A.I. [Lawrence Livermore National Lab., CA (United States); MISDC of VNIIFTRI, Mendeleevo (Russian Federation); Shlyaptsev, V.N. [Lawrence Livermore National Lab., CA (United States); California Univ., Davis, CA (United States). DAS

2001-07-01

We have performed L-shell spectroscopy and one-dimensional (1-D) imaging of a line focus plasma from a laser-heated Fe polished slab using the tabletop COMET laser system at the Lawrence Livermore National Laboratory. These plasmas are used to generate a Ne-like Fe transient gain X-ray laser that is recorded simultaneously. A spherically-curved crystal spectrometer gives high resolution X-ray spectra of the n=3-2 and n=4-2 resonance lines with 1-D spatial resolution along the line focus. Spectra are presented for different laser pulse conditions. In addition, a variety of X-ray imaging techniques are described. We discuss imaging results from a double-slit X-ray camera with a spherically-curved crystal spectrometer. We show a high resolution Fe K-{alpha} spectrum from the X-ray laser target that indicates the presence of hot electrons in the X-ray laser plasma. (orig.)

Ultrashort x-ray pulse generation by nonlinear Thomson scattering of a relativistic electron with an intense circularly polarized laser pulse

Directory of Open Access Journals (Sweden)

F. Liu

2012-07-01

Full Text Available The nonlinear Thomson scattering of a relativistic electron with an intense laser pulse is calculated numerically. The results show that an ultrashort x-ray pulse can be generated by an electron with an initial energy of 5 MeV propagating across a circularly polarized laser pulse with a duration of 8 femtosecond and an intensity of about 1.1×10^{21}  W/cm^{2}, when the detection direction is perpendicular to the propagation directions of both the electron and the laser beam. The optimal values of the carrier-envelop phase and the intensity of the laser pulse for the generation of a single ultrashort x-ray pulse are obtained and verified by our calculations of the radiation characteristics.

Modeling and design of radiative hydrodynamic experiments with X-ray Thomson Scattering measurements on NIF

Science.gov (United States)

Ma, K. H.; Lefevre, H. J.; Belancourt, P. X.; MacDonald, M. J.; Doeppner, T.; Keiter, P. A.; Kuranz, C. C.; Johnsen, E.

2017-10-01

Recent experiments at the National Ignition Facility studied the effect of radiation on shock-driven hydrodynamic instability growth. X-ray radiography images from these experiments indicate that perturbation growth is lower in highly radiative shocks compared to shocks with negligible radiation flux. The reduction in instability growth is attributed to ablation from higher temperatures in the foam for highly radiative shocks. The proposed design implements the X-ray Thomson Scattering (XRTS) technique in the radiative shock tube platform to measure electron temperatures and densities in the shocked foam. We model these experiments with CRASH, an Eulerian radiation hydrodynamics code with block-adaptive mesh refinement, multi-group radiation transport and electron heat conduction. Simulations are presented with SiO2 and carbon foams for both the high temperature, radiative shock and the low-temperature, hydrodynamic shock cases. Calculations from CRASH give estimations for shock speed, electron temperature, effective ionization, and other quantities necessary for designing the XRTS diagnostic measurement. This work is funded by the LLNL under subcontract B614207, and was performed under the auspices of the U.S. DOE by LLNL under Contract No. DE-AC52-07NA27344.

Polarization and dipole effects in hard X-ray photoelectron spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Novak, M. [Universite Libre de Bruxelles, Service de Metrologie Nucleaire (CP 165/84), 50 av. F. D. Roosevelt, B-1050 Brussels (Belgium); Pauly, N., E-mail: nipauly@ulb.ac.be [Universite Libre de Bruxelles, Service de Metrologie Nucleaire (CP 165/84), 50 av. F. D. Roosevelt, B-1050 Brussels (Belgium); Dubus, A. [Universite Libre de Bruxelles, Service de Metrologie Nucleaire (CP 165/84), 50 av. F. D. Roosevelt, B-1050 Brussels (Belgium)

2012-03-15

Highlights: Black-Right-Pointing-Pointer X-rays are unpolarized or linearly polarized. Black-Right-Pointing-Pointer A difference of polarization implies a variation in path travelled by the photoelectrons. Black-Right-Pointing-Pointer We show the influence of the polarization on the partial intensity distributions. Black-Right-Pointing-Pointer We also point out the influence of the dipole approximation. Black-Right-Pointing-Pointer We use Monte Carlo simulations. - Abstract: Hard X-ray photoelectron spectroscopy (HXPS) using X-rays in the 1.5-15 keV energy range generated by synchrotron sources becomes an increasingly important analysis technique due to its potential for bulk sensitive measurements. However, besides their high energy, another characteristic of photons generated by synchrotron sources is their linear polarization while X-rays from Al K{alpha} or Mg K{alpha} for instance are unpolarized. This difference implies a possible variation in total path travelled by the photoelectrons generated by the X-rays inside the medium and consequently a modification of the resulting spectrum shape. We show the influence of the polarization on the partial intensity distributions, namely the number of electrons escaping after n inelastic scattering events, for photoelectron with energies of 0.5, 1, 2, 3, 4 and 5 keV and originating from Si 1s{sub 1/2}, Cu 1s{sub 1/2}, Cu 2p{sub 3/2}, Au 4d{sub 3/2} and Au 4f{sub 7/2} subshells. Moreover, we point out the influence of the dipole approximation leading to an underestimation of the partial intensity distributions due to the neglect of the forward-backward asymmetry of the angular photoelectron distribution.

Stellar and solar X-ray polarimetry

Energy Technology Data Exchange (ETDEWEB)

Novick, R [Columbia Univ., New York (USA)

1975-12-01

The scientific motivation for X-ray polarimetry is discussed with particular emphasis on the information that might be obtained on the binary X-ray pulsars in addition to a number of other classes of objects including solar flares. Detailed discussions are given for Thomson-scattering and Bragg-crystal polarimeters with numerical estimates for the sensitivity of various existing and proposed instruments.

Human thyroid specimen imaging by fluorescent x-ray computed tomography with synchrotron radiation

Science.gov (United States)

Takeda, Tohoru; Yu, Quanwen; Yashiro, Toru; Yuasa, Tetsuya; Hasegawa, Yasuo; Itai, Yuji; Akatsuka, Takao

1999-09-01

Fluorescent x-ray computed tomography (FXCT) is being developed to detect non-radioactive contrast materials in living specimens. The FXCT system consists of a silicon (111) channel cut monochromator, an x-ray slit and a collimator for fluorescent x ray detection, a scanning table for the target organ and an x-ray detector for fluorescent x-ray and transmission x-ray. To reduce Compton scattering overlapped on the fluorescent K(alpha) line, incident monochromatic x-ray was set at 37 keV. The FXCT clearly imaged a human thyroid gland and iodine content was estimated quantitatively. In a case of hyperthyroidism, the two-dimensional distribution of iodine content was not uniform, and thyroid cancer had a small amount of iodine. FXCT can be used to detect iodine within thyroid gland quantitatively and to delineate its distribution.

X-ray Thomson scattering in warm dense matter at low frequencies

International Nuclear Information System (INIS)

Murillo, Michael S.

2010-01-01

The low-frequency portion of the x-ray Thomson scattering spectrum is determined by electrons that follow the slow ion motion. This ion motion is characterized by the ion-ion dynamic structure factor, which contains a wealth of information about the ions, including structure and collective modes. The frequency-integrated (diffraction) contribution is considered first. An effective dressed-particle description of warm dense matter is derived from the quantum Ornstein-Zernike equations, and this is used to identify a Yukawa model for warm dense matter. The efficacy of this approach is validated by comparing a predicted structure with data from the extreme case of a liquid metal; good agreement is found. A Thomas-Fermi model is then introduced to allow the separation of bound and free states at finite temperatures, and issues with the definition of the ionization state in warm dense matter are discussed. For applications, analytic structure factors are given on either side of the Kirkwood line. Finally, several models are constructed for describing the slow dynamics of warm dense matter. Two classes of models are introduced that both satisfy the basic sum rules. One class of models is the 'plasmon-pole'-like class, which yields the dispersion of ion-acoustic waves. Damping is then included via generalized hydrodynamics models that incorporate viscous contributions.

REACHING ULTRA HIGH PEAK CHARACTERISTICS IN RELATIVISTIC THOMSON BACKSCATTERING

International Nuclear Information System (INIS)

POGORELSKY, I.V.; BEN ZVI, I.; HIROSE, T.; KASHIWAGI, S.; YAKIMENKO, V.; KUSCHE, K.; SIDDONS, P.; ET AL

2001-01-01

The concept of x-ray laser synchrotron sources (LSS) based on Thomson scattering between laser photons and relativistic electrons leads to future femtosecond light-source facilities fit to multidisciplinary research in ultra-fast structural dynamics. Enticed by these prospects, the Brookhaven Accelerator Test Facility (ATF) embarked into development of the LSS based on a combination of a photocathode RF linac and a picosecond CO 2 laser. We observed the record 1.7 x 10 8 x-ray photons/pulse yield generated via relativistic Thomson scattering between the 14 GW CO 2 laser and 60 MeV electron beam

Warm dense matter and Thomson scattering at FLASH

International Nuclear Information System (INIS)

Faeustlin, Roland Rainer

2010-05-01

X-ray free electron lasers are powerful tools to investigate moderately to strongly correlated solid density low temperature plasmas, named warm dense matter. These plasmas are of most interest for astrophysics and laser plasma interaction, particularly inertial confinement fusion. This work utilizes the ultrashort soft x-ray pulse duration and high brilliance of the free electron laser in Hamburg, FLASH, to generate warm dense matter and to study its ultrafast processes. The techniques applied are absorption measurement, emission spectroscopy and Thomson scattering. Radiative hydrodynamics and Thomson scattering simulations are used to investigate the impact of temperature and density gradients in the sample and to fit the experimental data. The measurements result in a comprehensive picture of soft x-ray matter interaction related to warm dense matter and yield insight into ultrafast equilibration and relaxation mechanisms, in particular impact ionization and radiative recombination. (orig.)

Warm dense matter and Thomson scattering at FLASH

Energy Technology Data Exchange (ETDEWEB)

Faeustlin, Roland Rainer

2010-05-15

X-ray free electron lasers are powerful tools to investigate moderately to strongly correlated solid density low temperature plasmas, named warm dense matter. These plasmas are of most interest for astrophysics and laser plasma interaction, particularly inertial confinement fusion. This work utilizes the ultrashort soft x-ray pulse duration and high brilliance of the free electron laser in Hamburg, FLASH, to generate warm dense matter and to study its ultrafast processes. The techniques applied are absorption measurement, emission spectroscopy and Thomson scattering. Radiative hydrodynamics and Thomson scattering simulations are used to investigate the impact of temperature and density gradients in the sample and to fit the experimental data. The measurements result in a comprehensive picture of soft x-ray matter interaction related to warm dense matter and yield insight into ultrafast equilibration and relaxation mechanisms, in particular impact ionization and radiative recombination. (orig.)

Development of a Wolter Optic X-ray Imager on Z

Science.gov (United States)

Fein, Jeffrey R.; Ampleford, David J.; Vogel, Julia K.; Kozioziemski, Bernie; Walton, Christopher C.; Wu, Ming; Ayers, Jay; Ball, Chris J.; Bourdon, Chris J.; Maurer, Andrew; Pivovaroff, Mike; Ramsey, Brian; Romaine, Suzanne

2017-10-01

A Wolter optic x-ray imager is being developed for the Z Machine to study the dynamics of warm x-ray sources with energies above 10 keV. The optic is adapted from observational astronomy and uses multilayer-coated, hyperbolic and parabolic x-ray mirrors to form a 2D image with predicted 100- μm resolution over a 5x5-mm field of view. The imager is expected to have several advantages over a simple pinhole camera. In particular, it can form quasi mono-energetic images due to the inherent band-pass nature of the x-ray mirrors from Bragg diffraction. As well, its larger collection solid angle can lead to an overall increase in efficiency for the x-rays in the desirable energy band. We present the design of the imaging system, which is initially optimized to view Mo K-alpha x-rays (17.5 keV). In addition, we will present preliminary measurements of the point-spread function as well as the spectral sensitivity of the instrument. Sandia National Laboratories is a multimission laboratory managed and operated by NTESS, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. DOE's NNSA under contract DE-NA-0003525.

A Platform for X-Ray Thomson Scattering Measurements of Radiation Hydrodynamics Experiments on the NIF

Science.gov (United States)

Lefevre, Heath; Ma, Kevin; Belancourt, Patrick; MacDonald, Michael; Doeppner, Tilo; Keiter, Paul; Kuranz, Carolyn

2017-10-01

A recent experiment on the National Ignition Facility (NIF) radiographed the evolution of the Rayleigh-Taylor (RT) instability under high and low drive cases. This experiment showed that under a high drive the growth rate of the RT instability is reduced relative to the low drive case. The high drive launches a radiative shock, increases the temperature of the post-shock region, and ablates the spikes, which reduces the RT growth rate. The plasma parameters must be measured to validate this claim. We present a target design for making X-Ray Thomson Scattering (XRTS) measurements on radiation hydrodynamics experiments on NIF to measure the electron temperature of the shocked region in the above cases. Specifically, we show that a previously fielded NIF radiation hydrodynamics platform can be modified to allow sufficient signal and temperature resolution for XRTS measurements. This work is funded by the NNSA-DS and SC-OFES Joint Program in High-Energy-Density Laboratory Plasmas, Grant Number DE-NA0002956 and the National Science Foundation through the Basic Plasma Science and Engineering program.

Pleiades: A Sub-picosecond Tunable X-ray Source at the LLNL Electron Linac

International Nuclear Information System (INIS)

Slaughter, Dennis; Springer, Paul; Le Sage, Greg; Crane, John; Ditmire, Todd; Cowan, Tom; Anderson, Scott G.; Rosenzweig, James B.

2002-01-01

The use of ultra fast laser pulses to generate very high brightness, ultra short (fs to ps) pulses of x-rays is a topic of great interest to the x-ray user community. In principle, femto-second-scale pump-probe experiments can be used to temporally resolve structural dynamics of materials on the time scale of atomic motion. The development of sub-ps x-ray pulses will make possible a wide range of materials and plasma physics studies with unprecedented time resolution. A current project at LLNL will provide such a novel x-ray source based on Thomson scattering of high power, short laser pulses with a high peak brightness, relativistic electron bunch. The system is based on a 5 mm-mrad normalized emittance photo-injector, a 100 MeV electron RF linac, and a 300 mJ, 35 fs solid-state laser system. The Thomson x-ray source produces ultra fast pulses with x-ray energies capable of probing into high-Z metals, and a high flux per pulse enabling single shot experiments. The system will also operate at a high repetition rate (∼ 10 Hz). (authors)

On the theory of X-ray pulsar radiation

International Nuclear Information System (INIS)

Zheleznyakov, V.V.

1981-01-01

The origin of hard X-ray spectrum (continuum and cyclotron lines) of pulsars in binary systems is discussed. A model of the polar region of a neutron star consisting of a hot spot in a dense plasma atmosphere with a quasi-homogeneous magnetic field and an extended accreting column in an inhomogeneous dipolar field is investigated. In the hot spot bremsstrahlung and Thomson scattering form continuum radiation, while bremsstrahlung and cyclotron scattering produce the absorption cyclotron lines. By the observed continuum intensity one can estimate the maximum distances to pulsars. Cyclotron scattering in gyro-resonant layers localized in the accreting column leads to a general attenuation of the radiation of a hot spot, but is unable to ensure the formation of cyclotron lines. For strong accretion the hot spot radiation becomes insignificant, the lines disappear and the pulsating component of an X-ray pulsar is produced by the accreting column bremsstrahlung transformed by Thomson scattering. (orig.)

Long time scale hard X-ray variability in Seyfert 1 galaxies

Science.gov (United States)

Markowitz, Alex Gary

This dissertation examines the relationship between long-term X-ray variability characteristics, black hole mass, and luminosity of Seyfert 1 Active Galactic Nuclei. High dynamic range power spectral density functions (PSDs) have been constructed for six Seyfert 1 galaxies. These PSDs show "breaks" or characteristic time scales, typically on the order of a few days. There is resemblance to PSDs of lower-mass Galactic X-ray binaries (XRBs), with the ratios of putative black hole masses and variability time scales approximately the same (106--7) between the two classes of objects. The data are consistent with a linear correlation between Seyfert PSD break time scale and black hole mass estimate; the relation extrapolates reasonably well over 6--7 orders of magnitude to XRBs. All of this strengthens the case for a physical similarity between Seyfert galaxies and XRBs. The first six years of RXTE monitoring of Seyfert 1s have been systematically analyzed to probe hard X-ray variability on multiple time scales in a total of 19 Seyfert is in an expansion of the survey of Markowitz & Edelson (2001). Correlations between variability amplitude, luminosity, and black hole mass are explored, the data support the model of PSD movement with black hole mass suggested by the PSD survey. All of the continuum variability results are consistent with relatively more massive black holes hosting larger X-ray emission regions, resulting in 'slower' observed variability. Nearly all sources in the sample exhibit stronger variability towards softer energies, consistent with softening as they brighten. Direct time-resolved spectral fitting has been performed on continuous RXTE monitoring of seven Seyfert is to study long-term spectral variability and Fe Kalpha variability characteristics. The Fe Kalpha line displays a wide range of behavior but varies less strongly than the broadband continuum. Overall, however, there is no strong evidence for correlated variability between the line and

Diagnostic X-ray sources-present and future

Science.gov (United States)

Behling, Rolf; Grüner, Florian

2018-01-01

This paper compares very different physical principles of X-ray production to spur ideation. Since more than 120 years, bremsstrahlung from X-ray tubes has been the workhorse of medical diagnostics. Generated by X-ray segments comprised of X-ray tubes and high-voltage generators in the various medical systems, X-ray photons in the spectral range between about 16 keV and 150 keV deliver information about anatomy and function of human patients and in pre-clinical animal studies. Despite of strides to employ the wave nature of X-rays as phase sensitive means, commercial diagnostic X-ray systems available until the time of writing still rely exclusively on measuring the attenuation and scattering of X-rays by matter. Significant activities in research aim at building highly brilliant short pulse X-ray sources, based on e.g. synchrotron radiation, free electron lasers and/or laser wake-field acceleration of electrons followed by wiggling with magnetic structures or Thomson scattering in bunches of light. While both approaches, non-brilliant and brilliant sources, have different scope of application, we speculate that a combination may expand the efficacy in medical application. At this point, however, severe technical and commercial difficulties hinder closing this gap. This article may inspire further development and spark innovation in this important field.

Plasma instability control toward high fluence, high energy x-ray continuum source

Science.gov (United States)

Poole, Patrick; Kirkwood, Robert; Wilks, Scott; Blue, Brent

2017-10-01

X-ray source development at Omega and NIF seeks to produce powerful radiation with high conversion efficiency for material effects studies in extreme fluence environments. While current K-shell emission sources can achieve tens of kJ on NIF up to 22 keV, the conversion efficiency drops rapidly for higher Z K-alpha energies. Pulsed power devices are efficient generators of MeV bremsstrahlung x-rays but are unable to produce lower energy photons in isolation, and so a capability gap exists for high fluence x-rays in the 30 - 100 keV range. A continuum source under development utilizes instabilities like Stimulated Raman Scattering (SRS) to generate plasma waves that accelerate electrons into high-Z converter walls. Optimizing instabilities using existing knowledge on their elimination will allow sufficiently hot and high yield electron distributions to create a superior bremsstrahlung x-ray source. An Omega experiment has been performed to investigate the optimization of SRS and high energy x-rays using Au hohlraums with parylene inner lining and foam fills, producing 10× greater x-ray yield at 50 keV than conventional direct drive experiments on the facility. Experiment and simulation details on this campaign will be presented. This work was performed under the auspices of the US DoE by LLNL under Contract No. DE-AC52-07NA27344.

X-Ray Characterization of Non-Equilibrium Solid Solutions

Energy Technology Data Exchange (ETDEWEB)

Brown, A; Rosdahl, Oe

1975-07-01

The Rudman approach to composition line broadening in X-ray diffraction patterns, originally designed for the study of diffusion in alloys, is seen to provide a basis for characterizing inhomogeneous solid solutions. Limitations, imposed on this treatment when the cell dimensions of the primary components differ by less than 0.1 A, are attributable to experimental effects such as instrument broadening. These limitations can be overcome by a rigorous numerical treatment of the measured data. Thus, separate elimination of the Kalpha{sub 2} radiation component followed by iterative deconvolution are advocated for the recovery of the intrinsic broadening. This course of action is made possible chiefly through the availability of large, fast memory computers and primary data recorded in the form of a step scan on punched paper tape. The characteristics of inhomogeneous solid solutions made available by the above treatment are the identity of closely similar, solid solution phases, the frequency distribution curve for a chosen component, and the degree of homogeneity of the X-ray sample

Flash of the Cathode Rays: A History of J J Thomson's Electron

International Nuclear Information System (INIS)

Rechenberg, Helmut

1997-01-01

The author, a senior physicist from Berkeley having some experience in historical accounts, covers well the standard story of J J Thomson's discovery of the electron, one hundred years ago. Starting from the investigations of cathode rays in Germany, France and mainly England, the successful path of J J is covered in some detail using available information (letters, notebooks, diaries, publications), as well as his later work on positive rays and the atomic model. Lesser emphasis is given to the parallel developments connected with the Zeeman effect. However, a synopsis of the story of β-rays, the measurement of the elementary charge and the rise of the Rutherford - Bohr nuclear model of the atom is included. Dahl presents the physical contents from the standard literature in a clear and convincing way. He illustrates the narrative with (well-chosen and well-reproduced) portraits of the people involved and sketches of their original apparatus. Hence the book can be recommended highly to physicists, who will be reminded of one of the most important events in the earlier history of their field. A broader public, including other scientists, and perhaps attentive high school graduates, might also benefit from the book, not to mention professional science historians (who may appreciate the detailed, reliable description of subtle experiments and their tricky interpretation). The author succeeds far less well in providing the general background (in the history of physics and beyond) of the Thomson story. The electron as a fundamental concept existed and was applied long before J Pluecker's discovery of cathodes rays (for example, by A-M Ampere and his successors), and the importance of the work by W Weber, F Neumann and R Clausius (to mention just a few scientists in the 19th century) is mainly suppressed. Dahl's treatment of P Lenard's work around 1900, for which Lenard won the Nobel prize before Thomson, is quite unfair. Further, Chapter 14 on the French N-rays and

WEAK HARD X-RAY EMISSION FROM TWO BROAD ABSORPTION LINE QUASARS OBSERVED WITH NuSTAR: COMPTON-THICK ABSORPTION OR INTRINSIC X-RAY WEAKNESS?

Energy Technology Data Exchange (ETDEWEB)

Luo, B.; Brandt, W. N. [Department of Astronomy and Astrophysics, 525 Davey Lab, The Pennsylvania State University, University Park, PA 16802 (United States); Alexander, D. M.; Hickox, R. [Department of Physics, Durham University, South Road, Durham DH1 3LE (United Kingdom); Harrison, F. A.; Fuerst, F.; Grefenstette, B. W.; Madsen, K. K. [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Stern, D. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Bauer, F. E. [Departamento de Astronomia y Astrofisica, Pontificia Universidad Catolica de Chile, Casilla 306, Santiago 22 (Chile); Boggs, S. E.; Craig, W. W. [Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States); Christensen, F. E. [DTU Space-National Space Institute, Technical University of Denmark, Elektrovej 327, DK-2800 Lyngby (Denmark); Comastri, A. [INAF-Osservatorio Astronomico di Bologna, Via Ranzani 1, I-40127 Bologna (Italy); Fabian, A. C. [Institute of Astronomy, Madingley Road, Cambridge CB3 0HA (United Kingdom); Farrah, D. [Department of Physics, Virginia Tech, Blacksburg, VA 24061 (United States); Fiore, F. [Osservatorio Astronomico di Roma, via Frascati 33, I-00040 Monteporzio Catone (Italy); Hailey, C. J. [Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); Matt, G. [Dipartimento di Matematica e Fisica, Universita degli Studi Roma Tre, via della Vasca Navale 84, I-00146 Roma (Italy); Ogle, P. [IPAC, California Institute of Technology, Mail Code 220-6, Pasadena, CA 91125 (United States); and others

2013-08-01

We present Nuclear Spectroscopic Telescope Array (NuSTAR) hard X-ray observations of two X-ray weak broad absorption line (BAL) quasars, PG 1004+130 (radio loud) and PG 1700+518 (radio quiet). Many BAL quasars appear X-ray weak, probably due to absorption by the shielding gas between the nucleus and the accretion-disk wind. The two targets are among the optically brightest BAL quasars, yet they are known to be significantly X-ray weak at rest-frame 2-10 keV (16-120 times fainter than typical quasars). We would expect to obtain Almost-Equal-To 400-600 hard X-ray ({approx}> 10 keV) photons with NuSTAR, provided that these photons are not significantly absorbed (N{sub H} {approx}< 10{sup 24} cm{sup -2}). However, both BAL quasars are only detected in the softer NuSTAR bands (e.g., 4-20 keV) but not in its harder bands (e.g., 20-30 keV), suggesting that either the shielding gas is highly Compton-thick or the two targets are intrinsically X-ray weak. We constrain the column densities for both to be N{sub H} Almost-Equal-To 7 Multiplication-Sign 10{sup 24} cm{sup -2} if the weak hard X-ray emission is caused by obscuration from the shielding gas. We discuss a few possibilities for how PG 1004+130 could have Compton-thick shielding gas without strong Fe K{alpha} line emission; dilution from jet-linked X-ray emission is one likely explanation. We also discuss the intrinsic X-ray weakness scenario based on a coronal-quenching model relevant to the shielding gas and disk wind of BAL quasars. Motivated by our NuSTAR results, we perform a Chandra stacking analysis with the Large Bright Quasar Survey BAL quasar sample and place statistical constraints upon the fraction of intrinsically X-ray weak BAL quasars; this fraction is likely 17%-40%.

Soft x-ray virtual diagnostics for tokamak simulations

Science.gov (United States)

Kim, J. S.; Zhao, L.; Bogatu, I. N.; In, Y.; Turnbull, A.; Osborne, T.; Maraschek, M.; Comer, K.

2009-11-01

The numerical toolset, FAR-TECH Virtual Diagnostic Utility, for generating virtual experimental data based on theoretical models and comparing it with experimental data, has been developed for soft x-ray diagnostics on DIII-D. The virtual (or synthetic) soft x-ray signals for a sample DIII-D discharge are compared with the experimental data. The plasma density and temperature radial profiles needed in the soft x-ray signal modeling are obtained from experimental data, i.e., from Thomson scattering and electron cyclotron emission. The virtual soft x-ray diagnostics for the equilibriums have a good agreement with the experimental data. The virtual diagnostics based on an ideal linear instability also agree reasonably well with the experimental data. The agreements are good enough to justify the methodology presented here for utilizing virtual diagnostics for routine comparison of experimental data. The agreements also motivate further detailed simulations with improved physical models such as the nonideal magnetohydrodynamics contributions (resistivity, viscosity, nonaxisymmetric error fields, etc.) and other nonlinear effects, which can be tested by virtual diagnostics with various stability modeling.

Soft x-ray virtual diagnostics for tokamak simulations

International Nuclear Information System (INIS)

Kim, J. S.; Zhao, L.; Bogatu, I. N.; In, Y.; Turnbull, A.; Osborne, T.; Maraschek, M.; Comer, K.

2009-01-01

The numerical toolset, FAR-TECH Virtual Diagnostic Utility, for generating virtual experimental data based on theoretical models and comparing it with experimental data, has been developed for soft x-ray diagnostics on DIII-D. The virtual (or synthetic) soft x-ray signals for a sample DIII-D discharge are compared with the experimental data. The plasma density and temperature radial profiles needed in the soft x-ray signal modeling are obtained from experimental data, i.e., from Thomson scattering and electron cyclotron emission. The virtual soft x-ray diagnostics for the equilibriums have a good agreement with the experimental data. The virtual diagnostics based on an ideal linear instability also agree reasonably well with the experimental data. The agreements are good enough to justify the methodology presented here for utilizing virtual diagnostics for routine comparison of experimental data. The agreements also motivate further detailed simulations with improved physical models such as the nonideal magnetohydrodynamics contributions (resistivity, viscosity, nonaxisymmetric error fields, etc.) and other nonlinear effects, which can be tested by virtual diagnostics with various stability modeling.

A spherical model for the transient x-ray source A0620-00

International Nuclear Information System (INIS)

Dilworth, C.; Maraschi, L.; Perola, G.C.

1977-01-01

The continuum spectrum of the transient X-ray source A0620-00, from infrared to X-ray frequencies, is interpreted as emission from a uniform spherical cloud of hot gas in which the free-free spectrum is modified by Thomson scattering. On this basis, the radius and the density of the cloud, and the distance of the source, are derived. The change of the spectrum with the time indicates a decrease of both radius and density with decreasing luminosity. Considering the production of X-rays to be due to impulsive accretion in a low-mass binary system, these results open the question as to whether the accreting object is a white dwarf rather than a neutron star. (author)

Determination of low concentrations of thorium in geological materials by X-ray fluorescence; Determinacion de bajas concentraciones de torio en materiales geologicos mediante fluorescencia de rayos X

Energy Technology Data Exchange (ETDEWEB)

Roca, M.; Bayon, A.

1981-07-01

An X-ray fluorescence method for the determination of thorium in geological samples down to 2 ppm ThO{sub 2} has been developed. To achieve this determination limit an exposed area of the sample 42.5 mm in diameter is used, working with a molybdenum target tube operated at 90 kV and 30 m A. Corrections for background and line interference of the Rb K{alpha} radiation have been carefully considered and empirical correction coefficients calculated. (Author) 3 refs.

Soft X-ray emission studies of biomaterials

Energy Technology Data Exchange (ETDEWEB)

Kurmaev, E.Z. E-mail: kurmaev@ifmlrs.uran.ru; Werner, J.P.; Moewes, A.; Chiuzbaian, S.; Bach, M.; Ching, W.-Y.; Motozaki, W.; Otsuka, T.; Matsuya, S.; Endo, K.; Neumann, M

2004-07-01

Soft X-ray fluorescence measurements are used to characterize three groups of biomaterials: Vitamin B{sub 12} and derivatives, antioxidants (aspirin and paracetamol), and human teeth. We show that the chemical bonding in Vitamin B{sub 12} is characterized by the strong Co-C bond and the relatively weak Co-N bond. The Co-C bond in cyanocobalamin is found to be stronger than that of methylcobalamin leading to their different biological activity. The chemical bonding of paracetamol and aspirin is characterized by the formation of oxygen lone-pair {pi}-orbitals, which can neutralize free radicals and therefore be related to antioxidant activity of these compounds. Carbon K{alpha} emission spectra of a caries lesion suggest that the CaCO{sub 3} like phase exists in sound enamel and that a selective loss of carbonate occurs during the early stages of a caries attack.

High-efficiency high-energy Ka source for the critically-required maximum illumination of x-ray optics on Z using Z-petawatt-driven laser-breakout-afterburner accelerated ultrarelativistic electrons LDRD .

Energy Technology Data Exchange (ETDEWEB)

Sefkow, Adam B.; Bennett, Guy R.

2010-09-01

Under the auspices of the Science of Extreme Environments LDRD program, a <2 year theoretical- and computational-physics study was performed (LDRD Project 130805) by Guy R Bennett (formally in Center-01600) and Adam B. Sefkow (Center-01600): To investigate novel target designs by which a short-pulse, PW-class beam could create a brighter K{alpha} x-ray source than by simple, direct-laser-irradiation of a flat foil; Direct-Foil-Irradiation (DFI). The computational studies - which are still ongoing at this writing - were performed primarily on the RedStorm supercomputer at Sandia National Laboratories Albuquerque site. The motivation for a higher efficiency K{alpha} emitter was very clear: as the backlighter flux for any x-ray imaging technique on the Z accelerator increases, the signal-to-noise and signal-to-background ratios improve. This ultimately allows the imaging system to reach its full quantitative potential as a diagnostic. Depending on the particular application/experiment this would imply, for example, that the system would have reached its full design spatial resolution and thus the capability to see features that might otherwise be indiscernible with a traditional DFI-like x-ray source. This LDRD began FY09 and ended FY10.

X-ray emission spectroscopy of well-characterised non-LTE plasmas

International Nuclear Information System (INIS)

Bourgaux, A C; Bastiani-Ceccotti, S; Audebert, P; Marquès, J R; Vassura, L; Vinci, T; Jacquemot, S; Dorchies, F; Leguay, P M; Chung, H K; Bowen, C; Dervieux, V; Renaudin, P; Silvert, V

2016-01-01

This paper will present an experimental platform developed on LULI2000 to measure x-ray emission of non-LTE plasmas in well-defined hydrodynamic conditions thanks to implementation of a whole set of diagnostics, including time-resolved electronic and ionic Thomson scattering and self-optical pyrometry. K-, L- and M-shell spectra will be presented and the methodology, that has been developed to analyze them, discussed. (paper)

Laboratory-based recording of holographic fine structure in X-ray absorption anisotropy using polycapillary optics

Energy Technology Data Exchange (ETDEWEB)

Dabrowski, K.M. [Institute of Physics, Jagiellonian University, Reymonta 4, 30-059 Krakow (Poland); Korecki, P., E-mail: pawel.korecki@uj.edu.pl [Institute of Physics, Jagiellonian University, Reymonta 4, 30-059 Krakow (Poland)

2012-08-15

Highlights: Black-Right-Pointing-Pointer Holographic fine structures in X-ray absorption recorded using a tabletop setup. Black-Right-Pointing-Pointer Setup based on polycapillary collimating optics and an HOPG crystal. Black-Right-Pointing-Pointer Demonstration of element sensitivity by detection of X-ray fluorescence. Black-Right-Pointing-Pointer Potential of laboratory-based experiments for heavily doped crystals and thin films. - Abstract: A tabletop setup composed of a collimating polycapillary optics and a highly oriented pyrolytic graphite monochromator (HOPG) was characterized and used for recording two-dimensional maps of X-ray absorption anisotropy (XAA). XAA originates from interference of X-rays directly inside the sample. Depending on experimental conditions, fine structures in XAA can be interpreted in terms of X-ray holograms or X-ray standing waves and can be used for an element selective atomic-resolved structural analysis. The implementation of polycapillary optics resulted in a two-order of magnitude gain in the radiant intensity (photons/s/solid angle) as compared to a system without optics and enabled efficient recording of XAA with a resolution of 0.15 Degree-Sign for Mo K{alpha} radiation. Element sensitivity was demonstrated by acquisition of distinct XAA signals for Ga and As atoms in a GaAs (1 1 1) wafer by using X-ray fluorescence as a secondary signal. These results indicate the possibility of performing laboratory-based XAA experiments for heavily doped single crystals or thin films. So far, because of the weak holographic modulation of XAA, such experiments could be only performed using synchrotron radiation.

High-Resolution X-Ray Spectra of the Symbiotic Star SS73 17

Science.gov (United States)

Eze, R. N. C.; Luna, G. J. M.; Smith, R. K.

2010-01-01

SS73 17 was an innocuous Mira-type symbiotic star until the International Gamma-Ray Astrophysics Laboratory and Swift discovered its bright hard X-ray emission, adding it to the small class of "hard X-ray emitting symbiotics." Suzaku observations in 2006 then showed it emits three bright iron lines as well, with little to no emission in the 0.3-2.0 keV bandpass. We present here follow-up observations with the Chandra High Energy Transmission Grating and Suzaku that confirm the earlier detection of strong emission lines of Fe K(alpha) fluorescence, Fe XXV and Fe XXVI but also show significantly more soft X-ray emission. The high-resolution spectrum also shows emission lines of other highly ionized ions as Si xiv and possibly S XVI. In addition, a re-analysis of the 2006 Suzaku data using the latest calibration shows that the hard (15-50 keV) X-ray emission is brighter than previously thought and remains constant in both the 2006 and 2008 data. The G ratio calculated from the Fe xxv lines shows that these lines are thermal, not photoionized, in origin.With the exception of the hard X-ray emission, the spectra from both epochs can be fit using thermal radiation assuming a differential emission measure based on a cooling-flow model combined with a full and partial absorber. We show that acceptable fits can be obtained for all the data in the 1-10 keV band varying only the partial absorber. Based on the temperature and accretion rate, the thermal emission appears to be arising from the boundary layer between the accreting white dwarf and the accretion disk.

Time-resolved Thomson scattering on high-intensity laser-produced hot dense helium plasmas

International Nuclear Information System (INIS)

Sperling, P; Liseykina, T; Bauer, D; Redmer, R

2013-01-01

The introduction of brilliant free-electron lasers enables new pump–probe experiments to characterize warm and hot dense matter states, i.e. systems at solid-like densities and temperatures of one to several hundred eV. Such extreme conditions are relevant for high-energy density studies such as, e.g., in planetary physics and inertial confinement fusion. We consider here a liquid helium jet pumped with a high-intensity optical short-pulse laser that is subsequently probed with brilliant soft x-ray radiation. The optical short-pulse laser generates a strongly inhomogeneous helium plasma which is characterized with particle-in-cell simulations. We derive the respective Thomson scattering spectrum based on the Born–Mermin approximation for the dynamic structure factor considering the full density and temperature-dependent Thomson scattering cross section throughout the target. We observe plasmon modes that are generated in the interior of the target and study their temporal evolution. Such pump–probe experiments are promising tools to measure the important plasma parameters density and temperature. The method described here can be applied to various pump–probe scenarios by combining optical lasers, soft x-rays and hard x-ray sources. (paper)

A preliminary investigation for application of an advanced x-ray diffraction analyzer to in-process texture assessment of aluminum alloy sheet

International Nuclear Information System (INIS)

Ruud, C.O.; Snoha, D.J.

1989-01-01

The objective of this preliminary investigation was to assess the possibility of the use of rapid x-ray diffraction technology to nondestructively distinguish various texture conditions of aluminum can stock. Twelve samples of aluminum alloy can stock sheet were supplied by two manufacturers. The samples varied in thickness from 0.128 to 0.0124 inch and in texture from 2.8% to 11.0% as measured by a cup drawing earing test. The results for Cu K-alpha and Cr K-alpha radiation on suites of aluminum can stock samples from two manufacturers, in both hot rolled can stock precursor gages of 0.80 and 0.125 inch and in the final gage, show there is a good correlation between the peak intensity area function and the texture. These preliminary results provide an indication that the instrumentation and techniques applied could be optimized and refined for application to rapid, in-process nondestructive inspection of rolled aluminum can stock

Fluorescent x-ray computed tomography with synchrotron radiation using fan collimator

Science.gov (United States)

Takeda, Tohoru; Akiba, Masahiro; Yuasa, Tetsuya; Kazama, Masahiro; Hoshino, Atsunori; Watanabe, Yuuki; Hyodo, Kazuyuki; Dilmanian, F. Avraham; Akatsuka, Takao; Itai, Yuji

1996-04-01

We describe a new system of fluorescent x-ray computed tomography applied to image nonradioactive contrast materials in vivo. The system operates on the basis of computed tomography (CT) of the first generation. The experiment was also simulated using the Monte Carlo method. The research was carried out at the BLNE-5A bending-magnet beam line of the Tristan Accumulation Ring in Kek, Japan. An acrylic cylindrical phantom containing five paraxial channels of 5 and 4 mm diameters was imaged. The channels were filled with a diluted iodine-based contrast material, with iodine concentrations of 2 mg/ml and 500 (mu) g/ml. Spectra obtained with the system's high purity germanium (HPGe) detector separated clearly the K(alpha ) and K(beta 1) x-ray fluorescent lines, and the Compton scattering. CT images were reconstructed from projections generated by integrating the counts in these spectral lines. The method had adequate sensitivity and detection power, as shown by the experiment and predicted by the simulations, to show the iodine content of the phantom channels, which corresponded to 1 and 4 (mu) g iodine content per pixel in the reconstructed images.

Calculation of x-ray spectra emerging from an x-ray tube. Part I. Electron penetration characteristics in x-ray targets

International Nuclear Information System (INIS)

Poludniowski, Gavin G.; Evans, Philip M.

2007-01-01

The penetration characteristics of electron beams into x-ray targets are investigated for incident electron kinetic energies in the range 50-150 keV. The frequency densities of electrons penetrating to a depth x in a target, with a fraction of initial kinetic energy, u, are calculated using Monte Carlo methods for beam energies of 50, 80, 100, 120 and 150 keV in a tungsten target. The frequency densities for 100 keV electrons in Al, Mo and Re targets are also calculated. A mixture of simple modeling with equations and interpolation from data is used to generalize the calculations in tungsten. Where possible, parameters derived from the Monte Carlo data are compared to experimental measurements. Previous electron transport approximations in the semiempirical models of other authors are discussed and related to this work. In particular, the crudity of the use of the Thomson-Whiddington law to describe electron penetration and energy loss is highlighted. The results presented here may be used towards calculating the target self-attenuation correction for bremsstrahlung photons emitted within a tungsten target

A NuSTAR Observation of the Reflection Spectrum of the Low-Mass X-Ray Binary 4U 1728-34

Science.gov (United States)

Sleator, Clio C.; Tomsick, John A.; King, Ashley L.; Miller, Jon M.; Boggs, Steven E.; Bachetti, Matteo; Barret, Didier; Chenevez, Jerome; Christensen, Finn E.; Craig, William W.;

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)

Planetary X-ray studies: past, present and future

Science.gov (United States)

Branduardi-Raymont, Graziella

2016-07-01

Our solar system is a fascinating physics laboratory and X-ray observations are now firmly established as a powerful diagnostic tool of the multiple processes taking place in it. The science that X-rays reveal encompasses solar, space plasma and planetary physics, and the response of bodies in the solar system to the impact of the Sun's activity. This talk will review what we know from past observations and what we expect to learn in the short, medium and long term. Observations with Chandra and XMM-Newton have demonstrated that the origin of Jupiter's bright soft X-ray aurorae lies in the Charge eXchange (CX) process, likely to involve the interaction with atmospheric neutrals of local magnetospheric ions, as well as those carried in the solar wind. At higher energies electron bremsstrahlung is thought to be the X-ray emitting mechanism, while the whole planetary disk acts as a mirror for the solar X-ray flux via Thomson and fluorescent scattering. This 'X-ray mirror' phenomenon is all that is observed from Saturn's disk, which otherwise lacks X-ray auroral features. The Earth's X-ray aurora is bright and variable and mostly due to electron bremsstrahlung and line emission from atmospheric species. Un-magnetised planets, Venus and Mars, do not show X-ray aurorae but display the interesting combination of mirroring the solar X-ray flux and producing X-rays by Solar Wind Charge eXchange (SWCX) in their exospheres. These processes respond to different solar stimulation (photons and solar wind plasma respectively) hence their relative contributions are seen to vary according to the Sun's output. Present and future of planetary X-ray studies are very bright. We are preparing for the arrival of the Juno mission at Jupiter this summer and for coordinated observations with Chandra and XMM-Newton on the approach and later during Juno's orbital phase. These will allow direct correlation of the local plasma conditions with the X-ray emissions and the establishment of the

Easily exchangeable x-ray mirrors and hybrid monochromator modules a study of their performance

Energy Technology Data Exchange (ETDEWEB)

Lin, Fan. [Philips Analytical, Asia Pacific, Toa Payoh, (Singapore); Kogan, V. [Philips Analytical, EA Almelo, (Netherlands); Saito, K. [Philips Analytical, Tokyo, (Japan)

1999-12-01

Full text: PreFix prealigned optical mounts allowing rapid and easily changeover will be presented. The benefits of laterally graded multilayer X-Ray mirrors coupled with these Prefix mounts - conversion of divergent beam to parallel beam, increase of intensity by a factor of 3-7, monochromation to {alpha}1 and {alpha}2 and a dynamic range of 10 {sup 4-5} CpS will be demonstrated in areas such as Thin Film and Powder analysis. Data will be shown on a diffraction profile of thin film (Cr/SiO{sub 2}) with and without a mirror and Si powder with and without a mirror. Further enhancement will be demonstrated by combining a channel cut monochromator-collimator with an X-Ray mirror to produce a high intensity, parallel, pure Cu K{alpha}1 beam with a high intensity of up to 4.5 x 10{sup 8} cps and a divergence down to 0.01 deg. The applicability to various ranging from High Resolution to thin film/reflectivity to Rietveld structural refinement and to phase analysis will be shown. The Rocking curve of HEMT 10nm InGaAs on InP will be presented using various `standard` optics and hybrid optics, also Si powder and a Rietveld refinement of CuS0{sub 4}.5H{sub 2}0 and Aspirin. A comparison of the benefits and application of X-Ray Mirrors and Hybrid Mirror/Monochromators will be given. The data presented will show that by using X-Ray Mirrors and Hybrid modules the performance of standard `Laboratory` Diffractometers can be greatly enhanced to a level previously unachievable with great practical benefits. Copyright (1999) Australian X-ray Analytical Association Inc.

Final Summary of On-Orbit ADR Operation on Hitomis Soft X-Ray Spectrometer Instrument

Science.gov (United States)

Shirron, Peter

2016-01-01

The Soft X-ray Spectrometer (SXS) on the Astro-H observatory contains a 6x6 array of x-ray microcalorimeters that are cooled to 50 mK by an adiabatic demagnetization refrigerator (ADR). The ADR consists of three stages in order to provide stable detector cooling using either a 1.2 K superfluid helium bath or a 4.5 K Joule-Thomson (JT) cryocooler as its heat sink. Astro-H was renamed Hitomi after it was successfully launched in February 2016. The SXS carried approximately 36 liters of helium into orbit, and by day 5 the helium had cooled sufficiently (1.4 K) to allow operation of the ADR. This paper summarizes the ADRs performance during the 38 days that the satellite was operational.

Detailed hydrodynamic and X-ray spectrocsopic analysis of a laser-produced rapidly-explanding aluminium plasma

Czech Academy of Sciences Publication Activity Database

Chambers, D. M.; Glenzer, S. H.; Hawreliak, J.; Wolfrum, E.; Gouveia, A.; Lee, R. W.; Marjoribanks, R. S.; Renner, Oldřich; Sondhauss, P.; Topping, S.

2001-01-01

Roč. 71, - (2001), s. 237-247 ISSN 0022-4073 Grant - others:US DOE(US) DESG03-99D-P00297; US Department of Energy(US) W-7405 ENG 48 Institutional research plan: CEZ:AV0Z1010921 Keywords : laser produced plasma * x-ray spectroscopy * Thomson scattering * hydrocode Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.493, year: 2001

Collective Thomson scattering data analysis for Wendelstein 7-X

DEFF Research Database (Denmark)

Abramovic, I.; Pavone, A.; Svensson, J.

2017-01-01

Collective Thomson scattering (CTS) diagnostic is being installed on the Wendelstein 7-X stellarator to measure the bulk ion temperature in the upcoming experimental campaign. In order to prepare for the data analysis, a forward model of the diagnostic (eCTS) has been developed and integrated...... into the Bayesian data analysis framework Minerva. Synthetic spectra have been calculated with the forward model and inverted using Minerva in order to demonstrate the feasibility to measure the ion temperature in the presence of nuisance parameters that also influence CTS spectra. In this paper we report...... on the results of this anlysis and discuss the main sources of uncertainty in the CTS data analysis....

Monochromatic x-ray radiography of laser-driven spherical targets using high-energy, picoseconds LFEX laser

Science.gov (United States)

Sawada, Hiroshi; Fujioka, S.; Lee, S.; Arikawa, Y.; Shigemori, K.; Nagatomo, H.; Nishimura, H.; Sunahara, A.; Theobald, W.; Perez, F.; Patel, P. K.; Beg, F. N.

2015-11-01

Formation of a high density fusion fuel is essential in both conventional and advanced Inertial Confinement Fusion (ICF) schemes for the self-sustaining fusion process. In cone-guided Fast Ignition (FI), a metal cone is attached to a spherical target to maintain the path for the injection of an intense short-pulse ignition laser from blow-off plasma created when nanoseconds compression lasers drive the target. We have measured a temporal evolution of a compressed deuterated carbon (CD) sphere using 4.5 keV K-alpha radiography with the Kilo-Joule, picosecond LFEX laser at the Institute of Laser Engineering. A 200 μm CD sphere attached to the tip of a Au cone was directly driven by 9 Gekko XII beams with 300 J/beam in a 1.3 ns Gaussian pulse. The LFEX laser irradiated on a Ti foil to generate 4.51 Ti K-alpha x-ray. By varying the delay between the compression and backlighter lasers, the measured radiograph images show an increase of the areal density of the imploded target. The detail of the quantitative analyses to infer the areal density and comparisons to hydrodynamics simulations will be presented. This work was performed with the support and under the auspices of the NIFS Collaboration Research program (NIFS13KUGK072). H.S. was supported by the UNR's International Activities Grant program.

Modeling traveling-wave Thomson scattering using PIConGPU

Energy Technology Data Exchange (ETDEWEB)

Debus, Alexander; Schramm, Ulrich; Cowan, Thomas; Bussmann, Michael [Helmholtz-Zentrum Dresden-Rossendorf, Dresden (Germany); Steiniger, Klaus; Pausch, Richard; Huebl, Axel [Helmholtz-Zentrum Dresden-Rossendorf, Dresden (Germany); Technische Universitaet Dresden (Germany)

2016-07-01

Traveling-wave Thomson scattering (TWTS) laser pulses are pulse-front tilted and dispersion corrected beams that enable all-optical free-electron lasers (OFELs) up to the hard X-ray range. Electrons in such a side-scattering geometry experience the TWTS laser field as a continuous plane wave over centimeter to meter interaction lengths. After briefly discussing which OFEL scenarios are currently numerically accessible, we detail implementation and tests of TWTS beams within PIConGPU (3D-PIC code) and show how numerical dispersion and boundary effects are kept under control.

Novel diagnostics for warm dense matter: application to shock compressed target; Nouveaux diagnostics pour l'etude de la matiere dense et chaude: application aux cibles comprimees par choc laser

Energy Technology Data Exchange (ETDEWEB)

Ravasio, A

2007-03-15

In this work, we present 3 novel diagnostics for warm dense plasma (WDM) investigations: hard X-ray radiography, proton radiography and X-ray Thomson scattering. Each of these techniques is applied in shock compression experiments. The main objective consists in accessing a new parameter, in addition to shock and particle velocity, for EOS (Equation of State) measurements. In the first chapter we give a deep description of WDM states as strongly coupled and Fermi degenerate states. Then, we introduce how we have generated a WDM state in our experiment: the shock wave. We, in particular, illustrate its formation in the classical laser-matter interaction regime. In the second chapter the principles of standard probing techniques are presented. We see that energetic probe sources are necessary to investigate high Z dense plasmas. The third chapter is dedicated to X-ray radiography results. We report on a first direct density measurement of a shock compressed high Z target using K{alpha} hard X-ray radiation. These results are of great interests as they allow an in-situ characterization of high Z material, impossible with standard techniques. We show that probing a well known material as Al will allow the comparison between our data and the results from already validated simulations. In the fourth chapter, we present the results obtained from proton radiography on low density carbon foam. The data analysis will require the development of a specific Monte-Carlo code to simulate the proton propagation through the shocked target. The comparison of the simulations with the experimental data show a low dependency on density. The fifth chapter is devoted to X-ray Thomson scattering results. For the first time, we have performed collective x-ray Thomson scattering measurement from a shock compressed target, accessing to electron density and temperature. The obtained results are compared with simulated x-ray scattered spectra. The novel technique is then used in the

The Thomson scattering system at Wendelstein 7-X

Science.gov (United States)

Pasch, E.; Beurskens, M. N. A.; Bozhenkov, S. A.; Fuchert, G.; Knauer, J.; Wolf, R. C.

2016-11-01

This paper describes the design of the Thomson scattering system at the Wendelstein 7-X stellarator. For the first operation campaign we installed a 10 spatial channel system to cover a radial half profile of the plasma cross section. The start-up system is based on one Nd:YAG laser with 10 Hz repetition frequency, one observation optics, five fiber bundles with one delay line each, and five interference filter polychromators with five spectral channels and silicon avalanche diodes as detectors. High dynamic range analog to digital converters with 14 bit, 1 GS/s are used to digitize the signals. The spectral calibration of the system was done using a pulsed super continuum laser together with a monochromator. For density calibration we used Raman scattering in nitrogen gas. Peaked temperature profiles and flat density profiles are observed in helium and hydrogen discharges.

The response of the Fe K\\alpha line to changes in the X-ray illumination of accretion discs

OpenAIRE

Ballantyne, D. R.; Ross, R. R.

2002-01-01

X-ray reflection spectra from photoionized accretion discs in active galaxies are presented for a wide range of illumination conditions. The energy, equivalent width (EW) and flux of the Fe K line are shown to depend strongly on the ratio of illuminating flux to disc flux, Fx/Fdisc, the photon index of the irradiating power-law, \\Gamma, and the incidence angle of the radiation, i. When Fx/Fdisc \\leq 2 a neutral Fe K line is prominent for all but the largest values of \\Gamma. At higher illumin...

The gamma-ray emitting region of the jet in Cyg X-3

Science.gov (United States)

Zdziarski, Andrzej A.; Sikora, Marek; Dubus, Guillaume; Yuan, Feng; Cerutti, Benoit; Ogorzałek, Anna

2012-04-01

We study models of the γ-ray emission of Cyg X-3 observed by Fermi. We calculate the average X-ray spectrum during the γ-ray active periods. Then, we calculate spectra from Compton scattering of a photon beam into a given direction by isotropic relativistic electrons with a power-law distribution, both based on the Klein-Nishina cross-section and in the Thomson limit. Applying the results to scattering of stellar blackbody radiation in the inner jet of Cyg X-3, we find that a low-energy break in the electron distribution at a Lorentz factor of ˜300-103 is required by the shape of the observed X-ray/γ-ray spectrum in order to avoid overproducing the observed X-ray flux. The electrons giving rise to the observed γ-rays are efficiently cooled by Compton scattering, and the power-law index of the acceleration process is ≃2.5-3. The bulk Lorentz factor of the jet and the kinetic power before the dissipation region depend on the fraction of the dissipation power supplied to the electrons; if it is ≃1/2, the Lorentz factor is ˜2.5, and the kinetic power is ˜1038 erg s-1, which represents a firm lower limit on the jet power, and is comparable to the bolometric luminosity of Cyg X-3. Most of the power supplied to the electrons is radiated. The broad-band spectrum constrains the synchrotron and self-Compton emission from the γ-ray emitting electrons, which requires the magnetic field to be relatively weak, with the magnetic energy density ≲ a few times 10-3 of that in the electrons. The actual value of the magnetic field strength can be inferred from a future simultaneous measurement of the infrared and γ-ray fluxes.

X-ray spectroscopy from fusion plasmas

International Nuclear Information System (INIS)

Glenzer, S H.

1998-01-01

Our understanding of laser energy coupling into laser-driven inertial confinement fusion targets largely depends on our ability to accurately measure and simulate the plasma conditions in the underdense corona and in high density capsule implosions. X-ray spectroscopy is an important technique which has been applied to measure the total absorption of laser energy into the fusion target, the fraction of laser energy absorbed by hot electrons, and the conditions in the fusion capsule in terms of density and temperature. These parameters provide critical benchmarking data for performance studies of the fusion target and for radiation-hydrodynamic and laser-plasma interaction simulations. Using x-ray spectroscopic techniques for these tasks has required its application to non-standard conditions where kinetics models have not been extensively tested. In particular, for the conditions in high density implosions, where electron temperatures achieve 1 - 2 keV and electron densities reach 10 24 cm -3 evolving on time scales of 21 cm -3 and which am independently diagnosed with Thomson scattering and stimulated Raman scattering. We find that kinetics modeling is in good agreement with measured intensities of the dielectronic satellites of the He-β line (n= l-3) of Ar XVII. Applying these findings to the experimental results of capsule implosions provides additional evidence of temperature gradients at peak compression

X-ray filter for x-ray powder diffraction

Science.gov (United States)

Sinsheimer, John Jay; Conley, Raymond P.; Bouet, Nathalie C. D.; Dooryhee, Eric; Ghose, Sanjit

2018-01-23

Technologies are described for apparatus, methods and systems effective for filtering. The filters may comprise a first plate. The first plate may include an x-ray absorbing material and walls defining first slits. The first slits may include arc shaped openings through the first plate. The walls of the first plate may be configured to absorb at least some of first x-rays when the first x-rays are incident on the x-ray absorbing material, and to output second x-rays. The filters may comprise a second plate spaced from the first plate. The second plate may include the x-ray absorbing material and walls defining second slits. The second slits may include arc shaped openings through the second plate. The walls of the second plate may be configured to absorb at least some of second x-rays and to output third x-rays.

Multichord time-resolved electron temperature measurements by the x-ray absorber-foil method on TFTR

International Nuclear Information System (INIS)

Kiraly, J.; Bitter, M.; Efthimion, P.

1985-09-01

Absorber foils have been installed in the TFTR X-Ray Imaging System to permit measurement of the electron temperature along 10 to 30 chords spaced at 5-12.5 cm with a time resolution of less than 100 μs. The technique uses the ratio of x-ray fluxes transmitted through two different foils. The ratio depends mainly on electron temperature. Simulations show that strong impurity line radiation can distort this ratio. To correct for these effects, special beryllium-scandium filters are employed to select the line-free region between 2 and 4.5 keV. Other filter pairs allow corrections for Fe L and Ni L line radiation as well as Ti K and Ni K emission. Good accuracy is also obtained with simple beryllium filters, provided that impurity corrections are incorporated in the analysis, taking line intensities from the x-ray pulse-height analysis diagnostic. A description of modeling calculations and a comparison of temperature values from this diagnostic with data from the x-ray pulse height analysis, the electron cyclotron emission, and the Thomson scattering diagnostics are presented. Several applications of the absorber foil electron temperature diagnostic on TFTR are discussed

Multichord time-resolved electron temperature measurements by the x-ray absorber-foil method on TFTR

Energy Technology Data Exchange (ETDEWEB)

Kiraly, J.; Bitter, M.; Efthimion, P.; von Goeler, S.; Grek, B.; Hill, K.W.; Johnson, D.; McGuire, K.; Sauthoff, N.; Sesnic, S.

1985-09-01

Absorber foils have been installed in the TFTR X-Ray Imaging System to permit measurement of the electron temperature along 10 to 30 chords spaced at 5-12.5 cm with a time resolution of less than 100 ..mu..s. The technique uses the ratio of x-ray fluxes transmitted through two different foils. The ratio depends mainly on electron temperature. Simulations show that strong impurity line radiation can distort this ratio. To correct for these effects, special beryllium-scandium filters are employed to select the line-free region between 2 and 4.5 keV. Other filter pairs allow corrections for Fe L and Ni L line radiation as well as Ti K and Ni K emission. Good accuracy is also obtained with simple beryllium filters, provided that impurity corrections are incorporated in the analysis, taking line intensities from the x-ray pulse-height analysis diagnostic. A description of modeling calculations and a comparison of temperature values from this diagnostic with data from the x-ray pulse height analysis, the electron cyclotron emission, and the Thomson scattering diagnostics are presented. Several applications of the absorber foil electron temperature diagnostic on TFTR are discussed.

X-ray fluorescence imaging with polycapillary X-ray optics

International Nuclear Information System (INIS)

Yonehara, Tasuku; Yamaguchi, Makoto; Tsuji, Kouichi

2010-01-01

X-ray fluorescence spectrometry imaging is a powerful tool to provide information about the chemical composition and elemental distribution of a specimen. X-ray fluorescence spectrometry images were conventionally obtained by using a μ-X-ray fluorescence spectrometry spectrometer, which requires scanning a sample. Faster X-ray fluorescence spectrometry imaging would be achieved by eliminating the process of sample scanning. Thus, we developed an X-ray fluorescence spectrometry imaging instrument without sample scanning by using polycapillary X-ray optics, which had energy filter characteristics caused by the energy dependence of the total reflection phenomenon. In the present paper, we show that two independent straight polycapillary X-ray optics could be used as an energy filter of X-rays for X-ray fluorescence. Only low energy X-rays were detected when the angle between the two optical axes was increased slightly. Energy-selective X-ray fluorescence spectrometry images with projection mode were taken by using an X-ray CCD camera equipped with two polycapillary optics. It was shown that Fe Kα (6.40 keV) and Cu Kα (8.04 keV) could be discriminated for Fe and Cu foils.

Study of the ultrafast polarization dynamics in lithium borohydride by means of femtosecond X-ray diffraction

International Nuclear Information System (INIS)

Stingl, Johannes

2013-01-01

In this thesis the ultrafast electronic polarisation in the crystalline material lithium borohydride (LiBH 4 ) is examined. The material is excited by a femtosecond long optical pulse and scanned by a likewise short X-ray pulse. Using X-ray scattering the optically induced spatial rearrangement of electronic charge can be directly mapped with atomic spatial resolution. Copper K-alpha X-rays for the experiment are produced in a laboratory table-top laserplasma source with 1 kHz repetition rate. This radiation is then focused on a powdered sample. Debye-Scherrer rings produced from powder diffraction are collected on a large area detector and processed to yield intensity profiles. Using pump-probe technique the change in diffracted intensity, triggered by excitation with a femtosecond optical pulse is examined. The temporal resolution is given by the delay between pump and probe pulse. This way insight is gained into the dynamic electronic evolution of the system. Intensity changes can be correlated to changes in charge density in the relevant material to elucidate structural dynamics on the femtosecond time scale. Lithium borohydride was chosen since it displays necessary characteristics for the exploration of ultrafast electronic polarisation. Up to date there has been no spatially resolved research in the femtosecond regime elucidating this electronic phenomenon. This work presents the ultrafast resonse in Lithiumborhydrid (LiBH 4 ) to strong electronic fields with optical frequencies, which leads to charge relocation accompanied by electronic polarisation.

Accurate calculation of high harmonics generated by relativistic Thomson scattering

International Nuclear Information System (INIS)

Popa, Alexandru

2008-01-01

The recent emergence of the field of ultraintense laser pulses, corresponding to beam intensities higher than 10 18 W cm -2 , brings about the problem of the high harmonic generation (HHG) by the relativistic Thomson scattering of the electromagnetic radiation by free electrons. Starting from the equations of the relativistic motion of the electron in the electromagnetic field, we give an exact solution of this problem. Taking into account the Lienard-Wiechert equations, we obtain a periodic scattered electromagnetic field. Without loss of generality, the solution is strongly simplified by observing that the electromagnetic field is always normal to the direction electron-detector. The Fourier series expansion of this field leads to accurate expressions of the high harmonics generated by the Thomson scattering. Our calculations lead to a discrete HHG spectrum, whose shape and angular distribution are in agreement with the experimental data from the literature. Since no approximations were made, our approach is also valid in the ultrarelativistic regime, corresponding to intensities higher than 10 23 W cm -2 , where it predicts a strong increase of the HHG intensities and of the order of harmonics. In this domain, the nonlinear Thomson scattering could be an efficient source of hard x-rays

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

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.

The Weak Fe Fluorescence Line and Long-Term X-Ray Evolution of the Compton-Thick Active Galactic Nucleus in NGC7674

Science.gov (United States)

Ghandi, P.; Annuar, A.; Lansbury, G. B.; Stern, D.; Alexander, D. M.; Bauer, F. E.; Bianchi, S.; Boggs, S. E.; Boorman, P. G.; Brandt, W. N.;

Joseph John Thomson's models of matter and radiation in the early 1890s.

Science.gov (United States)

Bordoni, Stefano

In the late nineteenth century, Joseph John Thomson moved away from Maxwell's specific theoretical models of matter and energy, even though he continued to rely on the general framework of Maxwell's electromagnetic theory. In his 1893 book, he accomplished the conceptual drift towards a discrete model for matter, electricity, and fields. In Thomson's model, energy was linked to tubes of force, in particular to the aether contained in them and surrounding them: the energy was the kinetic energy of aether, of both a rotational and translational kind. Starting from Maxwell's electromagnetic fields, namely stresses propagating through a continuous solid medium, Thomson arrived at a representation of fields as a sea of discrete units carrying energy and momentum. He tried to transform Maxwell's theory into a unified picture in which atomic models of matter stood beside atomic models of fields. In 1904 his interpretation of X-rays was based on the integration between two complementary features of electromagnetic radiation, the continuity and the discreteness, and on some kind of fibrous aether. In recent secondary literature, the problematic conceptual link between J. J. Thomson's theory and contemporary theories on electromagnetic radiation has been underestimated. On the contrary, in the first half of the twentieth century, some physicists inquired into that link, and a widespread debate emerged, misunderstandings included.

X-ray astronomy

International Nuclear Information System (INIS)

Giacconi, R.; Gursky, H.

1974-01-01

This text contains ten chapters and three appendices. Following an introduction, chapters two through five deal with observational techniques, mechanisms for the production of x rays in a cosmic setting, the x-ray sky and solar x-ray emission. Chapters six through ten include compact x-ray sources, supernova remnants, the interstellar medium, extragalactic x-ray sources and the cosmic x-ray background. Interactions of x rays with matter, units and conversion factors and a catalog of x-ray sources comprise the three appendices. (U.S.)

High-Resolution X-ray Emission and X-ray Absorption Spectroscopy

NARCIS (Netherlands)

Groot, F.M.F. de

2000-01-01

In this review, high-resolution X-ray emission and X-ray absorption spectroscopy will be discussed. The focus is on the 3d transition-metal systems. To understand high-resolution X-ray emission and reso-nant X-ray emission, it is first necessary to spend some time discussing the X-ray absorption

Design of a 4.8-m ring for inverse Compton scattering x-ray source

Directory of Open Access Journals (Sweden)

H. S. Xu

2014-07-01

Full Text Available In this paper we present the design of a 50 MeV compact electron storage ring with 4.8-meter circumference for the Tsinghua Thomson scattering x-ray source. The ring consists of four dipole magnets with properly adjusted bending radii and edge angles for both horizontal and vertical focusing, and a pair of quadrupole magnets used to adjust the horizontal damping partition number. We find that the dynamic aperture of compact storage rings depends essentially on the intrinsic nonlinearity of the dipole magnets with small bending radius. Hamiltonian dynamics is found to agree well with results from numerical particle tracking. We develop a self-consistent method to estimate the equilibrium beam parameters in the presence of the intrabeam scattering, synchrotron radiation damping, quantum excitation, and residual gas scattering. We also optimize the rf parameters for achieving a maximum x-ray flux.

Flash X-ray

International Nuclear Information System (INIS)

Sato, Eiichi

2003-01-01

Generation of quasi-monochromatic X-ray by production of weakly ionized line plasma (flash X-ray), high-speed imaging by the X-ray and high-contrast imaging by the characteristic X-ray absorption are described. The equipment for the X-ray is consisted from the high-voltage power supply and condenser, turbo molecular pump, and plasma X-ray tube. The tube has a long linear anticathode to produce the line plasma and flash X-ray at 20 kA current at maximum. X-ray spectrum is measured by the imaging plate equipped in the computed radiography system after diffracted by a LiF single crystal bender. Cu anticathode generates sharp peaks of K X-ray series. The tissue images are presented for vertebra, rabbit ear and heart, and dog heart by X-ray fluoroscopy with Ce anticathode. Generation of K-orbit characteristic X-ray with extremely low bremsstrahung is to be attempted for medical use. (N.I.)

Thomson scattering from near-solid density plasmas using soft x-ray free electron lasers

Energy Technology Data Exchange (ETDEWEB)

Holl, A; Bornath, T; Cao, L; Doppner, T; Dusterer, S; Forster, E; Fortmann, C; Glenzer, S H; Gregori, G; Laarmann, T; Meiwes-Broer, K H; Przystawik, A; Radcliffe, P; Redmer, R; Reinholz, H; Ropke, G; Thiele, R; Tiggesbaumker, J; Toleikis, S; Truong, N X; Tschentscher, T; Uschmann, I; Zastrau, U

2006-11-21

We propose a collective Thomson scattering experiment at the VUV free electron laser facility at DESY (FLASH) which aims to diagnose warm dense matter at near-solid density. The plasma region of interest marks the transition from an ideal plasma to a correlated and degenerate many-particle system and is of current interest, e.g. in ICF experiments or laboratory astrophysics. Plasma diagnostic of such plasmas is a longstanding issue. The collective electron plasma mode (plasmon) is revealed in a pump-probe scattering experiment using the high-brilliant radiation to probe the plasma. The distinctive scattering features allow to infer basic plasma properties. For plasmas in thermal equilibrium the electron density and temperature is determined from scattering off the plasmon mode.

X-Ray

Science.gov (United States)

... enema. What you can expect During the X-ray X-rays are performed at doctors' offices, dentists' offices, ... as those using a contrast medium. Your child's X-ray Restraints or other techniques may be used to ...

Synchrotron x-ray microbeam characteristics for x-ray fluorescence analysis

International Nuclear Information System (INIS)

Iida, Atsuo; Noma, Takashi

1995-01-01

X-ray fluorescence analysis using a synchrotron x-ray microprobe has become an indispensable technique for non-destructive micro-analysis. One of the most important parameters that characterize the x-ray microbeam system for x-ray fluorescence analysis is the beam size. For practical analysis, however, the photon flux, the energy resolution and the available energy range are also crucial. Three types of x-ray microbeam systems, including monochromatic and continuum excitation systems, were compared with reference to the sensitivity, the minimum detection limit and the applicability to various types of x-ray spectroscopic analysis. 16 refs., 5 figs

X-ray sky

International Nuclear Information System (INIS)

Gruen, M.; Koubsky, P.

1977-01-01

The history is described of the discoveries of X-ray sources in the sky. The individual X-ray detectors are described in more detail, i.e., gas counters, scintillation detectors, semiconductor detectors, and the principles of X-ray spectrometry and of radiation collimation aimed at increased resolution are discussed. Currently, over 200 celestial X-ray sources are known. Some were identified as nebulae, in some pulsations were found or the source was identified as a binary star. X-ray bursts of novae were also observed. The X-ray radiation is briefly mentioned of spherical star clusters and of extragalactic X-ray sources. (Oy)

Isotopic imaging via nuclear resonance fluorescence with laser-based Thomson radiation

Science.gov (United States)

Barty, Christopher P. J. [Hayward, CA; Hartemann, Frederic V [San Ramon, CA; McNabb, Dennis P [Alameda, CA; Pruet, Jason A [Brentwood, CA

2009-07-21

The present invention utilizes novel laser-based, high-brightness, high-spatial-resolution, pencil-beam sources of spectrally pure hard x-ray and gamma-ray radiation to induce resonant scattering in specific nuclei, i.e., nuclear resonance fluorescence. By monitoring such fluorescence as a function of beam position, it is possible to image in either two dimensions or three dimensions, the position and concentration of individual isotopes in a specific material configuration. Such methods of the present invention material identification, spatial resolution of material location and ability to locate and identify materials shielded by other materials, such as, for example, behind a lead wall. The foundation of the present invention is the generation of quasimonochromatic high-energy x-ray (100's of keV) and gamma-ray (greater than about 1 MeV) radiation via the collision of intense laser pulses from relativistic electrons. Such a process as utilized herein, i.e., Thomson scattering or inverse-Compton scattering, produces beams having diameters from about 1 micron to about 100 microns of high-energy photons with a bandwidth of .DELTA.E/E of approximately 10E.sup.-3.

Comptonization of low-frequency radiation in accretion disks Angular distribution and polarization of hard X-ray radiation

International Nuclear Information System (INIS)

Suniaev, R.A.; Titarchuk, L.G.

1984-01-01

Analytical consideration is given to the comptonization of photons and its effects on the radiation emitted from accretion disks of compact X-ray sources, such as black holes and neutron stars. Attention is given to the photon distribution during escape from the disk, the angular distribution of hard radiation from the disk, the polarization of hard radiation and the electron temperature distribution over the optical depth. It is shown that the hard radiation spectrum is independent of the low-frequency photon source distribution. The angular distribution and polarization of the outgoing X-rays are a function of the optical depth. A Thomson approximation is used to estimate the angular distribution of the hard radiation and the polarization over the disk. The polarization results are compared with OSO-8 satellite data for Cyg X-1 and show good agreement at several energy levels. 17 references

X-ray astronomy

International Nuclear Information System (INIS)

Culhane, J.L.; Sanford, P.W.

1981-01-01

X-ray astronomy has been established as a powerful means of observing matter in its most extreme form. The energy liberated by sources discovered in our Galaxy has confirmed that collapsed stars of great density, and with intense gravitational fields, can be studied by making observations in the X-ray part of the electromagnetic spectrum. The astronomical objects which emit detectable X-rays include our own Sun and extend to quasars at the edge of the Universe. This book describes the history, techniques and results obtained in the first twenty-five years of exploration. Space rockets and satellites are essential for carrying the instruments above the Earth's atmosphere where it becomes possible to view the X-rays from stars and nebulae. The subject is covered in chapters, entitled: the birth of X-ray astronomy; the nature of X-radiation; X-rays from the Sun; solar-flare X-rays; X-rays from beyond the solar system; supernovae and their remnants; X-rays from binary stars; white dwarfs and neutron stars; black holes; X-rays from galaxies and quasars; clusters of galaxies; the observatories of the future. (author)

Skull x-ray

Science.gov (United States)

X-ray - head; X-ray - skull; Skull radiography; Head x-ray ... There is low radiation exposure. X-rays are monitored and regulated to provide the minimum amount of radiation exposure needed to produce the image. Most ...

Neck x-ray

Science.gov (United States)

X-ray - neck; Cervical spine x-ray; Lateral neck x-ray ... There is low radiation exposure. X-rays are monitored so that the lowest amount of radiation is used to produce the image. Pregnant women and ...

X-ray filter for chest X-rays

International Nuclear Information System (INIS)

Ferlic, D.J.

1984-01-01

A description is given of an X-ray filter comprised of a sheet of radiation absorbing material with an opening corresponding to the spine and central portion of the heart. The upper portion of the filter exhibits a relatively narrow opening which becomes gradually wider toward the lower portion of the filter. This filter will permit an acceptable density level of x-ray exposure for the lungs while allowing a higher level of x-ray exposure for the mediastinum areas of the body. (author)

X-ray optics and X-ray microscopes: new challenges

International Nuclear Information System (INIS)

Susini, J.

2004-01-01

Soon after the discovery of X-rays in 1895 by W. Roentgen, it became rapidly clear that the methods traditionally used in the visible light regime, namely refraction, diffraction and reflection were difficult to apply for X-ray optics. The physical origins of these difficulties are closely linked to the very nature of interaction of X-rays with matter. The small deviation δ of the refractive index of condensed matter from unity makes it difficult to extend refraction-based optics from the optical spectral region to the X-ray region because the refraction angle is proportional to δ. Similarly it is very challenging to extend diffraction-based focusing techniques to X-rays because the diffraction angle scales inversely with wavelength. Finally, the use of reflection-based optics is also limited by the very small critical angle for total reflection. All those fundamental limitations prevented for almost one century, the development of X-ray microscopy whereas electron microscopy became a standard tool. In the past twenty years, interests for X-ray microscopy revived, mainly because of several major advances in X-ray sources and X-ray optics. X-ray microscopy techniques are now emerging as powerful and complementary tools for submicron investigations. Soft X-ray microscopes offer traditionally the possibility to form direct images of thick hydrated biological material in near-native environment, at a spatial resolution well beyond that achievable with visible light microscopy. Natural contrast is available in the soft X-ray region, in the so-called ''water-window'', due to the presence of absorption edges of the major constituents (C,N,O). Recent advances in manufacturing techniques have enlarged the accessible energy range of micro-focussing optics and offer new applications in a broad range of disciplines. X-ray microscopy in the 1 - 30 keV energy range is better suited for fluorescence to map trace elements, tomography for 3D imaging and micro-diffraction. The

X-ray filter for chest x-rays

International Nuclear Information System (INIS)

Ferlic, D.J.

1984-01-01

Filter for use in medical x-ray apparatus to permit higher intensity x-ray exposure in the heart and mediastinum area while maintaining a normal level of x-ray exposure in other areas of the body, particlarly in the lung area. The filter comprises a sheet of radiation absorbing material having an opening therein, said opening corresponding to the spine and central portion of the heart. Accordingly, the upper portion of the filter exhibits a relatively narrow opening which becomes gradually wider toward the lower portion of the filter

X-ray geometrical smoothing effect in indirect x-ray-drive implosion

International Nuclear Information System (INIS)

Mochizuki, Takayasu; Sakabe, Shuji; Yamanaka, Chiyoe

1983-01-01

X-ray geometrical smoothing effect in indirect X-ray drive pellet implosion for inertial confinement fusion has been numerically analyzed. Attainable X-ray driven ablation pressure has been found to be coupled with X-ray irradiation uniformity. (author)

Towards a comprehensive X-ray approach for studying the photosynthetic manganese complex-XANES, K{alpha}/K{beta}/K{beta}-satellite emission lines, RIXS, and comparative computational approaches for selected model complexes

Energy Technology Data Exchange (ETDEWEB)

Zaharieva, I; Chernev, P; Risch, M; Gerencser, L; Haumann, M; Dau, H [Free University Berlin, FB Physik, Arnimallee 14, D-14195 Berlin (Germany); Berggren, G; Shevchenko, D; Anderlund, M [Dept. of Photochemistry and Molecular Science, Uppsala University, Box 523, S-751 20 Uppsala (Sweden); Weng, T C, E-mail: holger.dau@fu-berlin.d, E-mail: michael.haumann@fu-berlin.d [European Synchrotron Radiation Facility, BP 220, F-38043 Grenoble Cedex (France)

2009-11-15

Advanced X-ray spectroscopy experiments can contribute to elucidation of the mechanism of water oxidation in biological (tetra-manganese complex of Photosystem II) and artificial systems. Although the electronic structure of the catalytic metal site is of high interest, it is experimentally not easily accessible. Therefore, we and other researchers are working towards a comprehensive approach involving a combination of methods, namely (1) quantitative analysis of X-ray absorption near-edge structure (XANES) spectra collected at the K-edge and, in the long run, at the L-edge of manganese; (2) high-resolution X-ray emission spectroscopy (XES) of K{alpha} and K{beta} lines, (3) two-dimensional resonant inelastic X-ray scattering (RIXS) spectra. Collection of these spectroscopic data sets requires state-of-the-art synchrotron radiation facilities as well as experimental strategies to minimize the radiation-induced modifications of the samples. Data analysis requires the use and development of appropriate theoretical tools. Here, we present exemplary data collected for three multi-nuclear synthetic Mn complexes with the Mn ions in the oxidation states II, III, and IV, and for Mn{sup VII} of the permanganate ion. Emission spectra are calculated for the Mn{sup VII} ion using both multiple-scattering (MS) approach and time-dependent density functional theory (TDDFT).

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

International Nuclear Information System (INIS)

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

2014-01-01

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

Rothmund - Thomson Syndrome

Directory of Open Access Journals (Sweden)

Sharma N. L

2003-01-01

Full Text Available Rothmund-Thomson syndrome is a rare geno-photodermatosis of children. Poikilodermatous cutaneous changes, growth retardation, juvenile cataract and high incidence of malignancy are its classical features. A Thomson type of Rothmund-Thomson syndrome with characteristic poikiloderma congenitale, growth retardation, absence of juvenile cataract and parental non-consanguinity is described in an 8 year old Indian girl.

Comparison of x-ray output of inverter-type x-ray equipment

International Nuclear Information System (INIS)

Asano, Hiroshi; Miyake, Hiroyuki; Yamamoto, Keiichi

2000-01-01

The x-ray output of 54 inverter-type x-ray apparatuses used at 18 institutions was investigated. The reproducibility and linearity of x-ray output and variations among the x-ray equipment were evaluated using the same fluorescence meter. In addition, the x-ray apparatuses were re-measured using the same non-invasive instrument to check for variations in tube voltage, tube current, and irradiation time. The non-invasive instrument was calibrated by simultaneously obtaining measurements with an invasive instrument, employing the tube voltage and current used for the invasive instrument, and the difference was calculated. Reproducibility of x-ray output was satisfactory for all x-ray apparatuses. The coefficient of variation was 0.04 or less for irradiation times of 5 ms or longer. In 84.3% of all x-ray equipment, variation in the linearity of x-ray output was 15% or less for an irradiation time of 5 ms. However, for all the apparatuses, the figure was 50% when irradiation time was the shortest (1 to 3 ms). Variation in x-ray output increased as irradiation time decreased. Variation in x-ray output ranged between 1.8 and 2.5 compared with the maximum and minimum values, excluding those obtained at the shortest irradiation time. The relative standard deviation ranged from ±15.5% to ±21.0%. The largest variation in x-ray output was confirmed in regions irradiated for the shortest time, with smaller variations observed for longer irradiation times. The major factor responsible for variation in x-ray output in regions irradiated for 10 ms or longer, which is a relatively long irradiation time, was variation in tube current. Variation in tube current was slightly greater than 30% at maximum, with an average value of 7% compared with the preset tube current. Variations in x-ray output in regions irradiated for the shortest time were due to photographic effects related to the rise and fall times of the tube voltage waveform. Accordingly, in order to obtain constant x-ray

Chest X-Ray

Medline Plus

Full Text Available ... about chest radiography also known as chest x-rays. Chest x-rays are the most commonly performed x-ray exams and use a very small dose of ... of the inside of the chest. A chest x-ray is used to evaluate the lungs, heart and ...

Wide field X-ray telescopes: Detecting X-ray transients/afterglows related to gamma ray bursts

International Nuclear Information System (INIS)

Hudec, Rene; Pina, Ladislav; Inneman, Adolf; Gorenstein, Paul; Rezek, Tomas

1999-01-01

The recent discovery of X-ray afterglows of GRBs opens the possibility of analyses of GRBs by their X-ray detections. However, imaging X-ray telescopes in current use mostly have limited field of view. Alternative X-ray optics geometries achieving very large fields of view have been theoretically suggested in the 70ies but not constructed and used so far. We review the geometries and basic properties of the wide-field X-ray optical systems based on one- and two-dimensional lobster-eye geometry and suggest technologies for their development and construction. First results of the development of double replicated X-ray reflecting flats for use in one-dimensional X-ray optics of lobster eye type are presented and discussed. Optimum strategy for locating GRBs upon their X-ray counterparts is also presented and discussed

X-ray bursts observed with JEM-X

DEFF Research Database (Denmark)

Brandt, Søren Kristian; Chenevez, Jérôme; Lund, Niels

2006-01-01

We report on the search for X-ray bursts in the JEM-X X-ray monitor on INTEGRAL during the first two years of operations. More than 350 bursts from 25 different type-I X-ray burst sources were found.......We report on the search for X-ray bursts in the JEM-X X-ray monitor on INTEGRAL during the first two years of operations. More than 350 bursts from 25 different type-I X-ray burst sources were found....

X-Ray and Near-Infrared Spectroscopy of Dim X-Ray Point Sources Constituting the Galactic Ridge X-Ray Emission

Directory of Open Access Journals (Sweden)

Kumiko Morihana

2014-12-01

Full Text Available We present the results of X-ray and Near-Infrared observations of the Galactic Ridge X-ray Emission (GRXE. We extracted 2,002 X-ray point sources in the Chandra Bulge Field (l =0°.113, b = 1°.424 down to ~10-14.8 ergscm-2s-1 in 2-8 keV band with the longest observation (900 ks of the GRXE. Based on X-ray brightness and hardness, we classied the X-ray point sources into three groups: A (hard, B (soft and broad spectrum, and C (soft and peaked spectrum. In order to know populations of the X-ray point sources, we carried out NIR imaging and spectroscopy observation. We identied 11% of X-ray point sources with NIR and extracted NIR spectra for some of them. Based on X-ray and NIR properties, we concluded that non-thermal sources in the group A are mostly active galactic nuclei and the thermal sources are mostly white dwarf binaries such as cataclysmic variables (CVs and Pre-CVs. We concluded that the group B and C sources are X-ray active stars in flare and quiescence, respectively.

Bone X-Ray (Radiography)

Medline Plus

Full Text Available ... Resources Professions Site Index A-Z X-ray (Radiography) - Bone Bone x-ray uses a very small ... X-ray (Radiography)? What is Bone X-ray (Radiography)? An x-ray (radiograph) is a noninvasive medical ...

Bone X-Ray (Radiography)

Medline Plus

Full Text Available ... Professions Site Index A-Z X-ray (Radiography) - Bone Bone x-ray uses a very small dose ... limitations of Bone X-ray (Radiography)? What is Bone X-ray (Radiography)? An x-ray (radiograph) is ...

Bone X-Ray (Radiography)

Science.gov (United States)

... News Physician Resources Professions Site Index A-Z X-ray (Radiography) - Bone Bone x-ray uses a very small ... of Bone X-ray (Radiography)? What is Bone X-ray (Radiography)? An x-ray (radiograph) is a noninvasive ...

Abdomen X-Ray (Radiography)

Science.gov (United States)

... News Physician Resources Professions Site Index A-Z X-ray (Radiography) - Abdomen Abdominal x-ray uses a very small ... of an abdominal x-ray? What is abdominal x-ray? An x-ray (radiograph) is a noninvasive medical ...

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)

Bone X-Ray (Radiography)

Medline Plus

Full Text Available ... News Physician Resources Professions Site Index A-Z X-ray (Radiography) - Bone Bone x-ray uses a very ... of Bone X-ray (Radiography)? What is Bone X-ray (Radiography)? An x-ray (radiograph) is a noninvasive ...

Novel X-ray telescopes for wide-field X-ray monitoring

International Nuclear Information System (INIS)

Hudec, R.; Inneman, A.; Pina, L.; Sveda, L.

2005-01-01

We report on fully innovative very wide-field of view X-ray telescopes with high sensitivity as well as large field of view. The prototypes are very promising, allowing the proposals for space projects with very wide-field Lobster-eye X-ray optics to be considered. The novel telescopes will monitor the sky with unprecedented sensitivity and angular resolution of order of 1 arcmin. They are expected to contribute essentially to study and to understand various astrophysical objects such as AGN, SNe, Gamma-ray bursts (GRBs), X-ray flashes (XRFs), galactic binary sources, stars, CVs, X-ray novae, various transient sources, etc. The Lobster optics based X-ray All Sky Monitor is capable to detect around 20 GRBs and 8 XRFs yearly and this will surely significantly contribute to the related science

Bone X-Ray (Radiography)

Medline Plus

Full Text Available ... News Physician Resources Professions Site Index A-Z X-ray (Radiography) - Bone Bone x-ray uses a very small ... of Bone X-ray (Radiography)? What is Bone X-ray (Radiography)? An x-ray (radiograph) is a noninvasive ...

Perfect-crystal x-ray optics to treat x-ray coherence

International Nuclear Information System (INIS)

Yamazaki, Hiroshi; Ishikawa, Tetsuya

2007-01-01

X-ray diffraction of perfect crystals, which serve as x-ray monochromator and collimator, modifies coherence properties of x-ray beams. From the time-dependent Takagi-Taupin equations that x-ray wavefields obey in crystals, the reflected wavefield is formulated as an integral transform of a general incident wavefield with temporal and spatial inhomogeneity. A reformulation of rocking-curve profiles from the field solution of the Takagi-Taupin equations allows experimental evaluation of the mutual coherence function of x-ray beam. The rigorous relationship of the coherence functions between before and after reflection clarifies how the coherence is transferred by a crystal. These results will be beneficial to developers of beamline optics for the next generation synchrotron sources. (author)

X-ray scattering in X-ray fluorescence spectra with X-ray tube excitation - Modelling, experiment, and Monte-Carlo simulation

International Nuclear Information System (INIS)

Hodoroaba, V.-D.; Radtke, M.; Vincze, L.; Rackwitz, V.; Reuter, D.

2010-01-01

X-ray scattering may contribute significantly to the spectral background of X-ray fluorescence (XRF) spectra. Based on metrological measurements carried out with a scanning electron microscope (SEM) having attached a well characterised X-ray source (polychromatic X-ray tube) and a calibrated energy dispersive X-ray spectrometer (EDS) the accuracy of a physical model for X-ray scattering is systematically evaluated for representative samples. The knowledge of the X-ray spectrometer efficiency, but also of the spectrometer response functions makes it possible to define a physical spectral background of XRF spectra. Background subtraction relying on purely mathematical procedures is state-of-the-art. The results produced by the analytical model are at least as reliable as those obtained by Monte-Carlo simulations, even without considering the very challenging contribution of multiple scattering. Special attention has been paid to Compton broadening. Relevant applications of the implementation of the analytical model presented in this paper are the prediction of the limits of detection for particular cases or the determination of the transmission of X-ray polycapillary lenses.

X-Ray Scattering Applications Using Pulsed X-Ray Sources

Energy Technology Data Exchange (ETDEWEB)

Larson, B.C.

1999-05-23

Pulsed x-ray sources have been used in transient structural phenomena investigations for over fifty years; however, until the advent of synchrotrons sources and the development of table-top picosecond lasers, general access to ligh temporal resolution x-ray diffraction was relatively limited. Advances in diffraction techniques, sample excitation schemes, and detector systems, in addition to IncEased access to pulsed sources, have ld tO what is now a diverse and growing array of pulsed-source measurement applications. A survey of time-resolved investigations using pulsed x-ray sources is presented and research opportunities using both present and planned pulsed x-ray sources are discussed.

X-ray diagnostic installation for X-ray tomographic images

International Nuclear Information System (INIS)

Haendle, J.; Sklebitz, H.

1984-01-01

An exemplary embodiment includes at least one x-ray tube for the generation of an x-ray beam, a patient support, an image detector, and a control generator-connected with the x-ray tube and the image detector-for the purpose of moving the x-ray beam, and in opposition thereto, the image field of the image detector. There is connected to the control generator a layer height computer which calculates the enlargement from the geometric data for the tomogram. The image detector has a circuit-connected with the layer height computer-for the purpose of fading-in a marking for the dimensions in the layer plane

X-ray emission spectroscopy. X-ray fluorescence

International Nuclear Information System (INIS)

Despujols, J.

1992-01-01

Principles of X-ray emission spectrometry are first recalled, then wave-length dispersive and energy dispersive X-ray fluorescence spectrometer are described. They are essentially designed for qualitative and quantitative analysis of elements (Z>10). Sample preparation, calibration, corrections, interferences, accuracy are reviewed. Examples of use in different industries are given. (71 refs.)

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

The Swift Burst Alert Telescope Detected Seyfert 1 Galaxies: X-Ray Broadband Properties and Warm Absorbers

Science.gov (United States)

Winter, Lisa M.; Veilleux, Sylvain; McKernan, Barry; Kallman, T.

2012-01-01

We present results from an analysis of the broadband, 0.3-195 keV, X-ray spectra of 48 Seyfert 1-1.5 sources detected in the very hard X-rays with the Swift Burst Alert Telescope (BAT). This sample is selected in an all-sky survey conducted in the 14-195 keV band. Therefore, our sources are largely unbiased toward both obscuration and host galaxy properties. Our detailed and uniform model fits to Suzaku/BAT and XMM-Newton/BAT spectra include the neutral absorption, direct power-law, reflected emission, soft excess, warm absorption, and narrow Fe I K[alpha] emission properties for the entire sample. We significantly detect O VII and O VIII edges in 52% of our sample. The strength of these detections is strongly correlated with the neutral column density measured in the spectrum. Among the strongest detections, X-ray grating and UV observations, where available, indicate outflowing material. The ionized column densities of sources with O VII and O VIII detections are clustered in a narrow range with Nwarm [approx] 1021 cm-2, while sources without strong detections have column densities of ionized gas an order of magnitude lower. Therefore, we note that sources without strong detections likely have warm ionized outflows present but at low column densities that are not easily probed with current X-ray observations. Sources with strong complex absorption have a strong soft excess, which may or may not be due to difficulties in modeling the complex spectra of these sources. Still, the detection of a flat [Gamma] [approx] 1 and a strong soft excess may allow us to infer the presence of strong absorption in low signal-to-noise active galactic nucleus spectra. Additionally, we include a useful correction from the Swift BAT luminosity to bolometric luminosity, based on a comparison of our spectral fitting results with published spectral energy distribution fits from 33 of our sources.

X-ray detector for a panoramic X-ray unit

Energy Technology Data Exchange (ETDEWEB)

Cowell, D; Ensslin, F H

1976-01-15

The discovery deals with an X-ray detector suitable for the controlling of panoramic X-ray systems. It consists of a fluorescent image screen and a semiconductor photo cell. The output signal of the detector is proportional to the intensity of the X-radiation and the response time is large enough to follow the change of amplitude of the contours of the modulated X radiation. The detector with band-pass filter regulates, via a control system, the moving rate of the X-ray source and of the film opposite it in dependence of the intensity, so that a uniform exposure is ensured.

X-ray imaging with compound refractive lens and microfocus X-ray tube

OpenAIRE

Pina, Ladislav; Dudchik, Yury; Jelinek, Vaclav; Sveda, Libor; Marsik, Jiri; Horvath, Martin; Petr, Ondrej

2008-01-01

Compound refractive lenses (CRL), consisting of a lot number in-line concave microlenses made of low-Z material were studied. Lenses with focal length 109 mm and 41 mm for 8-keV X-rays, microfocus X-ray tube and X-ray CCD camera were used in experiments. Obtained images show intensity distribution of magnified microfocus X-ray source focal spot. Within the experiments, one lens was also used as an objective lens of the X-ray microscope, where the copper anode X-ray microfocus tube served as a...

Abdominal x-ray

Science.gov (United States)

Abdominal film; X-ray - abdomen; Flat plate; KUB x-ray ... There is low radiation exposure. X-rays are monitored and regulated to provide the minimum amount of radiation exposure needed to produce the image. Most ...

Ultra-short X-ray sources generated through laser-matter interaction and their applications

International Nuclear Information System (INIS)

Rousse, A.

2004-04-01

This work is dedicated to the sources of ultra-short X-rays. The K α source, the non-linear Thomson source, the betatron source and the X-γ source are presented. We show that a pump-probe experiment where the pump is a laser excitation and the probe is the X-K α ultra-short radiation, can be used to study the dynamics of material structure with a time resolution of 100 femtosecond. We describe 2 applications that have been achieved in the field of solid physics by using the diffraction technique with a time resolution in the range of the femtosecond. The first application has permitted the observation and characterization of the ultra-quick solid-phase transition that occurs on the surface of a semiconductor crystal. The second experiment deals with the role of optical phonons in the antecedent processes that lead to such ultra-quick solid-phase transitions. (A.C.)

X-ray spectroscopy and X-ray crystallography of metalloenzymes at XFELs

International Nuclear Information System (INIS)

Yano, Junko

2016-01-01

The ultra-bright femtosecond X-ray pulses provided by X-ray Free Electron Lasers (XFELs) open capabilities for studying the structure and dynamics of a wide variety of biological and inorganic systems beyond what is possible at synchrotron sources. Although the structure and chemistry at the catalytic sites have been studied intensively in both biological and inorganic systems, a full understanding of the atomic-scale chemistry requires new approaches beyond the steady state X-ray crystallography and X-ray spectroscopy at cryogenic temperatures. Following the dynamic changes in the geometric and electronic structure at ambient conditions, while overcoming X-ray damage to the redox active catalytic center, is key for deriving reaction mechanisms. Such studies become possible by using the intense and ultra-short femtosecond X-ray pulses from an XFEL, where sample is probed before it is damaged. We have developed methodology for simultaneously collecting crystallography data and X-ray emission spectra, using an energy dispersive spectrometer at ambient conditions. In addition, we have developed a way to collect metal L-edge data of dilute samples using soft X-rays at XFELs. The advantages and challenges of these methods will be described in this review. (author)

Chest X-Ray

Medline Plus

Full Text Available ... talk with you about chest radiography also known as chest x-rays. Chest x-rays are the ... treatment for a variety of lung conditions such as pneumonia, emphysema and cancer. A chest x-ray ...

Modern X-ray spectroscopy 3. X-ray fluorescence holography

International Nuclear Information System (INIS)

Hayashi, Kouichi

2008-01-01

X-ray fluorescence holography (XFH) provides three dimensional atomic images around specified elements. The XFH uses atoms as a wave source or monitor of interference field within a crystal sample, and therefore it can record both intensity and phase of scattered X-rays. Its current performance makes it possible to apply to ultra thin film, impurity and quasicrystal. In this article, I show the theory including solutions for twin image problem, advanced measuring system, data processing for reconstruction of the atomic images and for obtaining accurate atomic positions, applications using resonant X-ray scattering and X-ray excited optical luminescence, and an example of XFH result on the local structure around copper in silicon steal. (author)

X-ray holography: X-ray interactions and their effects

International Nuclear Information System (INIS)

London, R.A.; Trebes, J.E.; Rosen, M.D.

1988-01-01

The authors summarize a theoretical study of the interactions of x-rays with a biological sample during the creation of a hologram. The choice of an optimal wavelength for x-ray holography is discussed, based on a description of scattering by objects within an aqueous environment. The problem of the motion resulting from the absorption of x-rays during a short exposure is described. The possibility of using very short exposures in order to capture the image before motion can compromise the resolution is explored. The impact of these calculation on the question of the feasibility of using an x-ray laser for holography of biological structures is discussed. 12 refs., 2 figs

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

Modern X-ray difraction. X-ray diffractometry for material scientists, physicists, and chemicists

International Nuclear Information System (INIS)

Spiess, L.; Schwarzer, R.; Behnken, H.; Teichert, G.

2005-01-01

The book yields a comprehensive survey over the applications of X-ray diffraction in fields like material techniques, metallurgy, electrotechniques, machine engineering, as well as micro- and nanotechniques. The necessary fundamental knowledge on X-ray diffraction are mediated foundedly and illustratively. Thereby new techniques and evaluation procedures are presented as well as well known methods. The content: Production and properties of X radiation, diffraction of X radiation, hardware for X-ray diffraction, methods of X-ray diffraction, lattice-constant determination, phase analysis, X-ray profile analysis, crystal structure analysis, X-ray radiographic stress analysis, X-ray radiographic texture analysis, crystal orientation determination, pecularities at thin films, small angle scattering

X-Ray Exam: Pelvis

Science.gov (United States)

... Staying Safe Videos for Educators Search English Español X-Ray Exam: Pelvis KidsHealth / For Parents / X-Ray Exam: ... Ray Exam: Hip Broken Bones Getting an X-ray (Video) X-Ray (Video) View more Partner Message About Us ...

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

Development of x-ray laminography under an x-ray microscopic condition

International Nuclear Information System (INIS)

Hoshino, Masato; Uesugi, Kentaro; Takeuchi, Akihisa; Suzuki, Yoshio; Yagi, Naoto

2011-01-01

An x-ray laminography system under an x-ray microscopic condition was developed to obtain a three-dimensional structure of laterally-extended planar objects which were difficult to observe by x-ray tomography. An x-ray laminography technique was introduced to an x-ray transmission microscope with zone plate optics. Three prototype sample holders were evaluated for x-ray imaging laminography. Layered copper grid sheets were imaged as a laminated sample. Diatomite powder on a silicon nitride membrane was measured to confirm the applicability of this method to non-planar micro-specimens placed on the membrane. The three-dimensional information of diatom shells on the membrane was obtained at a spatial resolution of sub-micron. Images of biological cells on the membrane were also obtained by using a Zernike phase contrast technique.

Chest X-Ray

Medline Plus

Full Text Available ... by Image/Video Gallery Your Radiologist Explains Chest X-ray Transcript Welcome to Radiology Info dot org! Hello, ... you about chest radiography also known as chest x-rays. Chest x-rays are the most commonly performed ...

X-ray resonant magnetic reflectivity of stratified magnetic structures: Eigenwave formalism and application to a W/Fe/W trilayer

International Nuclear Information System (INIS)

Elzo, M.; Jal, E.; Bunau, O.; Grenier, S.; Joly, Y.; Ramos, A.Y.; Tolentino, H.C.N.; Tonnerre, J.M.; Jaouen, N.

2012-01-01

A formalism for the reflectivity of electromagnetic waves by magnetic materials is presented with an application. It is applied to retrieve the magnetic moment density along the depth of magnetic materials with arbitrary magnetic moment direction using matricial algebra, including roughness between layers. The reflectivity is derived following a classical description with Maxwell equations and a permittivity built from the quantum scattering amplitude. Approximations on the relative power of the Thomson scattering and the magnetic terms are trackable in order to evaluate the validity of the formalism case-by-case, from the optical light regime up to soft and hard X-rays. Eigenwaves are used throughout the whole formalism. In order to illustrate the methodology, we present an application to a W/Fe/W trilayer performed at the Fe L-edge, in the soft X-ray regime. - Highlights: → Magnetism at interfaces and in thin films is increasingly studied. → X-ray resonant magnetic reflectivity yields the in depth magnetization profile in thin films. → We present a formalism and methodology to study the data. → We illustrate the technique with an example.

Microfocussing of synchrotron X-rays using X-ray refractive lens

Indian Academy of Sciences (India)

X-ray lenses are fabricated in polymethyl methacrylate using deep X-ray lithography beamline of Indus-2. The focussing performance of these lenses is evaluated using Indus-2 and Diamond Light Source Ltd. The process steps for the fabrication of X-ray lenses and microfocussing at 10 keV at moderate and low emittance ...

First result from x-ray pulse height analyzer with radial scanning system for LHD

Science.gov (United States)

Muto, Sadatsugu; Morita, Shigeru

2001-01-01

Radial profiles of x-ray spectrum have been successfully obtained using an assembly of x-ray pulse height analyzer in large helical device. The observed profile is obtained from plasma heated by ICRF and neutral beam injection (NBI). As a detector, Si(Li) semiconductor is used with a histogramming memory and analog-to-digital converter (ADC) basically working at high counting rate up to 500 kcps. In routine operation a count rate of 62 kcps has been normally obtained with energy resolution better than 400 eV at iron Kα line. The assembly is equipped with four detectors and a radial scanning system which modulates sight lines of the detectors in major radius direction. The profiles of electron temperature and the intensity of metallic impurities have been obtained with a spatial resolution of a few centimeters. Measured electron temperature is in good agreement with that from Thomson scattering. The system is applicable to steady-state discharge. The design philosophy of the assembly and recent results on the performance tests are also presented.

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.)

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

Directory of Open Access Journals (Sweden)

L. Miaja-Avila

2015-03-01

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

X-ray instrumentation in astronomy

International Nuclear Information System (INIS)

Cuhlane, J.L.

1985-01-01

This book presents the proceedings of a conference devoted to x-ray instrumentation in astronomy. Special sections are: AXAF X-Ray Optical Systems; Specialized X-Ray Systems; X-Ray Optical Systems I; X-Ray Optical Systems II; Gas Filled X-Ray Detectors II; The NASA Advanced X-Ray Astrophysics Facility; X-Ray and EUV Spectrometers; Microchannel Plates; and Solid State Detectors

Panoramic Dental X-Ray

Science.gov (United States)

... Physician Resources Professions Site Index A-Z Panoramic Dental X-ray Panoramic dental x-ray uses a very small dose of ... x-ray , is a two-dimensional (2-D) dental x-ray examination that captures the entire mouth ...

Chest X-Ray

Medline Plus

Full Text Available ... I’d like to talk with you about chest radiography also known as chest x-rays. Chest x-rays are the most ... far outweighs any risk. For more information about chest x-rays, visit Radiology Info dot org. Thank you for your time! ...

Miniature x-ray point source for alignment and calibration of x-ray optics

International Nuclear Information System (INIS)

Price, R.H.; Boyle, M.J.; Glaros, S.S.

1977-01-01

A miniature x-ray point source of high brightness similar to that of Rovinsky, et al. is described. One version of the x-ray source is used to align the x-ray optics on the Argus and Shiva laser systems. A second version is used to determine the spatial and spectral transmission functions of the x-ray optics. The spatial and spectral characteristics of the x-ray emission from the x-ray point source are described. The physical constraints including size, intensity and thermal limitations, and useful lifetime are discussed. The alignment and calibration techniques for various x-ray optics and detector combinations are described

Subluminous X-ray binaries

NARCIS (Netherlands)

Armas Padilla, M.

2013-01-01

The discovery of the first X-ray binary, Scorpius X-1, by Giacconi et al. (1962), marked the birth of X-ray astronomy. Following that discovery, many additional X-ray sources where found with the first generation of X-ray rockets and observatories (e.g., UHURU and Einstein). The short-timescale

X-Ray Exam: Forearm

Science.gov (United States)

... Staying Safe Videos for Educators Search English Español X-Ray Exam: Forearm KidsHealth / For Parents / X-Ray Exam: ... Muscles, and Joints Broken Bones Getting an X-ray (Video) X-Ray (Video) View more Partner Message About Us ...

X-Ray Exam: Foot

Science.gov (United States)

... Staying Safe Videos for Educators Search English Español X-Ray Exam: Foot KidsHealth / For Parents / X-Ray Exam: ... Muscles, and Joints Broken Bones Getting an X-ray (Video) X-Ray (Video) View more Partner Message About Us ...

X-Ray Exam: Wrist

Science.gov (United States)

... Staying Safe Videos for Educators Search English Español X-Ray Exam: Wrist KidsHealth / For Parents / X-Ray Exam: ... Muscles, and Joints Broken Bones Getting an X-ray (Video) X-Ray (Video) View more Partner Message About Us ...

Thoracic spine x-ray

Science.gov (United States)

Vertebral radiography; X-ray - spine; Thoracic x-ray; Spine x-ray; Thoracic spine films; Back films ... There is low radiation exposure. X-rays are monitored and regulated to provide the minimum amount of radiation exposure needed to produce the image. Most ...

X-Ray Exam: Finger

Science.gov (United States)

... Staying Safe Videos for Educators Search English Español X-Ray Exam: Finger KidsHealth / For Parents / X-Ray Exam: ... Muscles, and Joints Broken Bones Getting an X-ray (Video) X-Ray (Video) View more Partner Message About Us ...

Soft x-ray lasers

International Nuclear Information System (INIS)

Matthews, D.L.; Rosen, M.D.

1988-01-01

One of the elusive dreams of laser physicists has been the development of an x-ray laser. After 25 years of waiting, the x-ray laser has at last entered the scientific scene, although those now in operation are still laboratory prototypes. They produce soft x rays down to about five nanometers. X-ray lasers retain the usual characteristics of their optical counterparts: a very tight beam, spatial and temporal coherence, and extreme brightness. Present x-ray lasers are nearly 100 times brighter that the next most powerful x-ray source in the world: the electron synchrotron. Although Lawrence Livermore National Laboratory (LLNL) is widely known for its hard-x-ray laser program which has potential applications in the Strategic Defense Initiative, the soft x-ray lasers have no direct military applications. These lasers, and the scientific tools that result from their development, may one day have a place in the design and diagnosis of both laser fusion and hard x-ray lasers. The soft x-ray lasers now in operation at the LLNL have shown great promise but are still in the primitive state. Once x-ray lasers become reliable, efficient, and economical, they will have several important applications. Chief among them might be the creation of holograms of microscopic biological structures too small to be investigated with visible light. 5 figs

76 FR 50272 - West, A Thomson Reuters Business, Thomson Reuters Legal Division, Including On-Site Leased...

Science.gov (United States)

2011-08-12

... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-75,099] West, A Thomson Reuters Business, Thomson Reuters Legal Division, Including On-Site Leased Workers From Adecco, Albuquerque, New... former workers of West, A Thomson Reuters Business, Thomson Reuters Legal Division, including On-Site...

Frequency filter of seed x-ray by use of x-ray laser medium. Toward the generation of the temporally coherent x-ray laser

International Nuclear Information System (INIS)

Hasegawa, Noboru; Kawachi, Tetsuya; Kishimoto, Maki; Sukegawa, Kouta; Tanaka, Momoko; Ochi, Yoshihiro; Nishikino, Masaharu; Nagashima, Keisuke; Kato, Yoshiaki; Renzhong, Tai

2009-01-01

We evaluate the characteristics of a higher-order harmonics light as a seed X-ray amplified through a laser-produced X-ray amplifier. The narrow spectral bandwidth of the X-ray amplifier works as the frequency filter of the seed X-ray, resulting in that only the temporally coherent X-ray is amplified. Experimental investigation using the 29th-order harmonic light of the Ti:sapphire laser at a wavelength of 26.9 nm together with a neon-like manganese X-ray laser medium shows evident spectral narrowing of the seed X-ray and amplification without serious diffraction effects on the propagation of the amplified X-ray beam. This implies that the present combination is potential to realize temporally coherent X-ray lasers, with an expected duration of approximately 400 fs. (author)

Joint European x-ray monitor (JEM-X): x-ray monitor for ESA's

DEFF Research Database (Denmark)

Schnopper, H.W.; Budtz-Joergensen, C.; Westergaard, Niels Jørgen Stenfeldt

1996-01-01

JEM-X will extend the energy range of the gamma ray instruments on ESA's INTEGRAL mission (SPI, IBIS) to include the x-ray band. JEM-X will provide images with arcminute angular resolution in the 2 - 60 keV band. The baseline photon detection system consists of two identical, high pressure, imagi...

Wide field x-ray telescopes: Detecting x-ray transients/afterglows related to GRBs

International Nuclear Information System (INIS)

Hudec, Rene; Pina, Ladislav; Inneman, Adolf; Gorenstein, Paul

1998-01-01

The recent discovery of X-ray afterglows of GRBs opens the possibility of analyses of GRBs by their X-ray detections. However, imaging X-ray telescopes in current use mostly have limited fields of view. Alternative X-ray optics geometries achieving very large fields of view have been theoretically suggested in the 70's but not constructed and used so far. We review the geometries and basic properties of the wide-field X-ray optical systems based on one- and two-dimensional lobster-eye geometry and suggest technologies for their development and construction. First results of the development of double replicated X-ray reflecting flats for use in one-dimensional X-ray optics of lobster-eye type are presented and discussed. The optimum strategy for locating GRBs upon their X-ray counterparts is also presented and discussed

Extending the methodology of X-ray crystallography to allow X-ray microscopy without X-ray optics

International Nuclear Information System (INIS)

Miao Jianwei; Kirz, Janos; Sayre, David; Charalambous, Pambos

2000-01-01

We demonstrate that the soft X-ray diffraction pattern from a micron-size noncrystalline specimen can be recorded and inverted to form a high-resolution image. The phase problem is overcome by oversampling the diffraction pattern. The image is obtained using an iterative algorithm. The technique provides a method for X-ray microscopy requiring no high-resolution X-ray optical elements or detectors. In the present work, a resolution of approximately 60 nm was obtained, but we believe that considerably higher resolution can be achieved

Dental X-ray apparatus

International Nuclear Information System (INIS)

Weiss, M.E.

1980-01-01

Intra-oral dental X-ray apparatus for panoramic radiography is described in detail. It comprises a tubular target carrier supporting at its distal end a target with an inclined forward face. Image definition is improved by positioning in the path of the X-rays a window of X-ray transmitting ceramic material, e.g. 90% oxide of Be, or Al, 7% Si0 2 . The target carrier forms a probe which can be positioned in the patient's mouth. X-rays are directed forwardly and laterally of the target to an X-ray film positioned externally. The probe is provided with a detachable sleeve having V-form arms of X-ray opaque material which serve to depress the tongue out of the radiation path and also shield the roof of the mouth and other regions of the head from the X-ray pattern. A cylindrical lead shield defines the X-ray beam angle. (author)

X-ray diagnostics for TFTR

International Nuclear Information System (INIS)

von Goeler, S.; Hill, K.W.; Bitter, M.

1982-12-01

A short description of the x-ray diagnostic preparation for the TFTR tokamak is given. The x-ray equipment consists of the limiter x-ray monitoring system, the soft x-ray pulse-height-analysis-system, the soft x-ray imaging system and the x-ray crystal spectrometer. Particular attention is given to the radiation protection of the x-ray systems from the neutron environment

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.)

Spatial correlation analysis of seismic noise for STAR X-ray infrastructure design

Science.gov (United States)

D'Alessandro, Antonino; Agostino, Raffaele; Festa, Lorenzo; Gervasi, Anna; Guerra, Ignazio; Palmer, Dennis T.; Serafini, Luca

2014-05-01

The Italian PON MaTeRiA project is focused on the creation of a research infrastructure open to users based on an innovative and evolutionary X-ray source. This source, named STAR (Southern Europe TBS for Applied Research), exploits the Thomson backscattering process of a laser radiation by fast-electron beams (Thomson Back Scattering - TBS). Its main performances are: X-ray photon flux 109-1010 ph/s, Angular divergence variable between 2 and 10 mrad, X-ray energy continuously variable between 8 keV and 150 keV, Bandwidth ΔE/E variable between 1 and 10%, ps time resolved structure. In order to achieve this performances, bunches of electrons produced by a photo-injector are accelerated to relativistic velocities by a linear accelerator section. The electron beam, few hundreds of micrometer wide, is driven by magnetic fields to the interaction point along a 15 m transport line where it is focused in a 10 micrometer-wide area. In the same area, the laser beam is focused after being transported along a 12 m structure. Ground vibrations could greatly affect the collision probability and thus the emittance by deviating the paths of the beams during their travel in the STAR source. Therefore, the study program to measure ground vibrations in the STAR site can be used for site characterization in relation to accelerator design. The environmental and facility noise may affect the X-ray operation especially if the predominant wavelengths in the microtremor wavefield are much smaller than the size of the linear accelerator. For wavelength much greater, all the accelerator parts move in phase, and therefore also large displacements cannot generate any significant effect. On the other hand, for wavelengths equal or less than half the accelerator size several parts could move in phase opposition and therefore small displacements could affect its proper functioning. Thereafter, it is important to characterize the microtremor wavefield in both frequencies and wavelengths domains

Bone X-Ray (Radiography)

Medline Plus

Full Text Available ... ray examination. X-rays usually have no side effects in the typical diagnostic range for this exam. ... x-rays. A Word About Minimizing Radiation Exposure Special care is taken during x-ray examinations to ...

Soft x-ray continuum radiation transmitted through metallic filters: An analytical approach to fast electron temperature measurements

International Nuclear Information System (INIS)

Delgado-Aparicio, L.; Hill, K.; Bitter, M.; Tritz, K.; Kramer, T.; Stutman, D.; Finkenthal, M.

2010-01-01

A new set of analytic formulas describes the transmission of soft x-ray continuum radiation through a metallic foil for its application to fast electron temperature measurements in fusion plasmas. This novel approach shows good agreement with numerical calculations over a wide range of plasma temperatures in contrast with the solutions obtained when using a transmission approximated by a single-Heaviside function [S. von Goeler et al., Rev. Sci. Instrum. 70, 599 (1999)]. The new analytic formulas can improve the interpretation of the experimental results and thus contribute in obtaining fast temperature measurements in between intermittent Thomson scattering data.

Semiconductor X-ray detectors

CERN Document Server

Lowe, Barrie Glyn

2014-01-01

Identifying and measuring the elemental x-rays released when materials are examined with particles (electrons, protons, alpha particles, etc.) or photons (x-rays and gamma rays) is still considered to be the primary analytical technique for routine and non-destructive materials analysis. The Lithium Drifted Silicon (Si(Li)) X-Ray Detector, with its good resolution and peak to background, pioneered this type of analysis on electron microscopes, x-ray fluorescence instruments, and radioactive source- and accelerator-based excitation systems. Although rapid progress in Silicon Drift Detectors (SDDs), Charge Coupled Devices (CCDs), and Compound Semiconductor Detectors, including renewed interest in alternative materials such as CdZnTe and diamond, has made the Si(Li) X-Ray Detector nearly obsolete, the device serves as a useful benchmark and still is used in special instances where its large, sensitive depth is essential. Semiconductor X-Ray Detectors focuses on the history and development of Si(Li) X-Ray Detect...

Thomson scattering on ELMO Bumpy Torus

International Nuclear Information System (INIS)

Cobble, J.A.

1985-04-01

Below 10 12 cm -3 density, a Thomson scattering experiment is an exacting task. Aside from the low signal level, the core plasma in this instance is bathed in high-energy x rays, surrounded by a glowing molecular surface plasma, and heated steady state by microwaves. This means that the noise level from radiation is high and the environment is extremely harsh-so harsh that much effort is required to overcome system damage. In spite of this, the ELMO Bumpy Torus (EBT) system has proven itself capable of providing reliable n/sub e/ and T/sub e/ measurements at densities as low as 2 x 10 11 cm -3 . Radial scans across 20 cm of the plasma diameter have been obtained on a routine basis, and the resulting information has been a great help in understanding confinement in the EBT plasma. The bulk electron properties are revealed as flat profiles of n/sub e/ and T/sub e/, with density ranging from 0.5 to 2.0 x 10 12 cm -3 and temperature decreasing from 100 to 20 eV as pressure in the discharge is increased at constant power. Evidence is presented for a suprathermal tail, which amounts to about 10% of the electron distribution at low pressures. The validity of this conclusion is supported by two independent sensitivity calibrations

Calibration of a two-color soft x-ray diagnostic for electron temperature measurement

Energy Technology Data Exchange (ETDEWEB)

Reusch, L. M., E-mail: lmmcguire@wisc.edu; Den Hartog, D. J.; Goetz, J.; McGarry, M. B. [University of Wisconsin - Madison, Madison, Wisconsin 53703 (United States); Franz, P. [Consorzio RFX, Padova (Italy); Stephens, H. D. [University of Wisconsin - Madison, Madison, Wisconsin 53703 (United States); Pierce College Fort Steilacoom, Lakewood, Washington 98498 (United States)

2016-11-15

The two-color soft x-ray (SXR) tomography diagnostic on the Madison Symmetric Torus is capable of making electron temperature measurements via the double-filter technique; however, there has been a 15% systematic discrepancy between the SXR double-filter (SXR{sub DF}) temperature and Thomson scattering (TS) temperature. Here we discuss calibration of the Be filters used in the SXR{sub DF} measurement using empirical measurements of the transmission function versus energy at the BESSY II electron storage ring, electron microprobe analysis of filter contaminants, and measurement of the effective density. The calibration does not account for the TS and SXR{sub DF} discrepancy, and evidence from experiments indicates that this discrepancy is due to physics missing from the SXR{sub DF} analysis rather than instrumentation effects.

X-ray apparatus

International Nuclear Information System (INIS)

Grady, J.K.

1985-01-01

X-ray apparatus is described which has a shutter between the X-ray source and the patient. The shutter controls the level of radiation to which the patient is exposed instead of merely discontinuing the electric power supplied to the source. When the shutter is opened a radiation sensor senses the level of X-radiation. When a preset quantity of X-radiation has been measured an exposure control closes the shutter. Instead of using the radiation sensor, the integrated power supplied to the anode of the X-ray source may be measured. (author)

Method for spatially modulating X-ray pulses using MEMS-based X-ray optics

Science.gov (United States)

Lopez, Daniel; Shenoy, Gopal; Wang, Jin; Walko, Donald A.; Jung, Il-Woong; Mukhopadhyay, Deepkishore

2015-03-10

A method and apparatus are provided for spatially modulating X-rays or X-ray pulses using microelectromechanical systems (MEMS) based X-ray optics. A torsionally-oscillating MEMS micromirror and a method of leveraging the grazing-angle reflection property are provided to modulate X-ray pulses with a high-degree of controllability.

Optical and X-ray studies of Compact X-ray Binaries in NGC 5904

Science.gov (United States)

Bhalotia, Vanshree; Beck-Winchatz, Bernhard

2018-06-01

Due to their high stellar densities, globular cluster systems trigger various dynamical interactions, such as the formation of compact X-ray binaries. Stellar collisional frequencies have been correlated to the number of X-ray sources detected in various clusters and we hope to measure this correlation for NGC 5904. Optical fluxes of sources from archival HST images of NGC 5904 have been measured using a DOLPHOT PSF photometry in the UV, optical and near-infrared. We developed a data analysis pipeline to process the fluxes of tens of thousands of objects using awk, python and DOLPHOT. We plot color magnitude diagrams in different photometric bands in order to identify outliers that could be X-ray binaries, since they do not evolve the same way as singular stars. Aligning previously measured astrometric data for X-ray sources in NGC 5904 from Chandra with archival astrometric data from HST will filter out the outlier objects that are not X-ray producing, and provide a sample of compact binary systems that are responsible for X-ray emission in NGC 5904. Furthermore, previously measured X-ray fluxes of NGC 5904 from Chandra have also been used to measure the X-ray to optical flux ratio and identify the types of compact X-ray binaries responsible for the X-ray emissions in NGC 5904. We gratefully acknowledge the support from the Illinois Space Grant Consortium.

CCD-based X-ray detectors for X-ray diffraction studies

International Nuclear Information System (INIS)

Ito, K.; Amemiya, Y.

1999-01-01

CCD-based X-ray detectors are getting to be used for X-ray diffraction studies especially in the studies where real time (automated) measurements and time-resolved measurements are required. Principles and designs of two typical types of CCD-based detectors are described; one is ths system in which x-ray image intensifiers are coupled to maximize the detective quantum efficiency for time-resolved measurements, and the other is the system in which tapered optical fibers are coupled for the reduction of the image into the CCD, which is optimized for automated measurements for protein crystallography. These CCD-based X-ray detectors have an image distortion and non-uniformity of response to be corrected by software. Correction schemes which we have developed are also described. (author)

Simulation of transmitted X-rays in a polycapillary X-ray lens

Energy Technology Data Exchange (ETDEWEB)

Peng, Shiqi [The Key Laboratory of Beam Technology and Material 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); Liu, Zhiguo, E-mail: liuzhiguo512@126.com [The Key Laboratory of Beam Technology and Material 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; Wang, Kai; Yi, Longtao; Yang, Kui; Chen, Man; Wang, Jinbang [The Key Laboratory of Beam Technology and Material 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)

2015-09-21

The geometrical description of capillary systems adjusted for the controlled guiding of X-rays and the basic theory of the transmission of X-rays are presented. A method of numerical calculation, based on Ray-Tracing theory, is developed to simulate the transmission efficiency of an X-ray parallel lens and the shape and size of the light spot gain from it. The simulation results for two half-lenses are in good agreement with the experimental results.

Microfocussing of synchrotron X-rays using X-ray refractive lens developed at Indus-2 deep X-ray lithography beamline

International Nuclear Information System (INIS)

Dhamgaye, V.P.; Tiwari, M.K.; Lodha, G.S.; Sawhney, K.J.S.

2014-01-01

X-ray lenses are fabricated in polymethyl methacrylate using deep X-ray lithography beamline of Indus-2. The focussing performance of these lenses is evaluated using Indus-2 and Diamond Light Source Ltd. The process steps for the fabrication of X-ray lenses and microfocussing at 10 keV at moderate and low emittance sources are compared. (author)

X pinch a point x-ray source

International Nuclear Information System (INIS)

Garg, A.B.; Rout, R.K.; Shyam, A.; Srinivasan, M.

1993-01-01

X ray emission from an X pinch, a point x-ray source has been studied using a pin-hole camera by a 30 kV, 7.2 μ F capacitor bank. The wires of different material like W, Mo, Cu, S.S.(stainless steel) and Ti were used. Molybdenum pinch gives the most intense x-rays and stainless steel gives the minimum intensity x-rays for same bank energy (∼ 3.2 kJ). Point x-ray source of size (≤ 0.5 mm) was observed using pin hole camera. The size of the source is limited by the size of the pin hole camera. The peak current in the load is approximately 150 kA. The point x-ray source could be useful in many fields like micro lithography, medicine and to study the basic physics of high Z plasmas. (author). 4 refs., 3 figs

Measuring a Truncated Disk in Aquila X-1

Science.gov (United States)

King, Ashley L.; Tomsick, John A.; Miller, Jon M.; Chenevez, Jerome; Barret, Didier; Boggs, Steven E.; Chakrabarty, Deepto; Christensen, Finn E.; Craig, William W.; Feurst, Felix;

Chest X-Ray

Medline Plus

Full Text Available ... by Image/Video Gallery Your Radiologist Explains Chest X-ray Transcript Welcome to Radiology Info dot org! Hello, ... d like to talk with you about chest radiography also known as chest x-rays. Chest x- ...

Compact X-ray sources: X-rays from self-reflection

Science.gov (United States)

Mangles, Stuart P. D.

2012-05-01

Laser-based particle acceleration offers a way to reduce the size of hard-X-ray sources. Scientists have now developed a simple scheme that produces a bright flash of hard X-rays by using a single laser pulse both to generate and to scatter an electron beam.

76 FR 45879 - West, a Thomson Reuters Business, Thomson Reuters Legal, Including On-Site Leased Workers From...

Science.gov (United States)

2011-08-01

... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-73,198] West, a Thomson Reuters Business, Thomson Reuters Legal, Including On-Site Leased Workers From Adecco, Including a Teleworker...-W-73,198 is hereby issued as follows: All workers of West, A Thomson Reuters Business, Thomson...

Phase-contrast X-ray imaging using an X-ray interferometer for biological imaging

Energy Technology Data Exchange (ETDEWEB)

Momose, Atsushi; Koyama, Ichiro [Tokyo Univ., Dept. of Applied Physics, Tokyo (Japan); Takeda, Tohoru; Itai, Yuji [Tsukuba Univ., Inst. of Clinical Medicine, Tsukuba, Ibaraki (Japan); Yoneyama, Akio [Hitachi Ltd., Advanced Research Laboratory, Saitama (Japan)

2002-04-01

The potential of phase-contrast X-ray imaging using an X-ray interferometer is discussed comparing with other phase-contrast X-ray imaging methods, and its principle of contrast generation is presented including the case of phase-contrast X-ray computed tomography. The status of current instrumentation is described and perspectives for practical applications are discussed. (author)

X-ray crystallography

Science.gov (United States)

2001-01-01

X-rays diffracted from a well-ordered protein crystal create sharp patterns of scattered light on film. A computer can use these patterns to generate a model of a protein molecule. To analyze the selected crystal, an X-ray crystallographer shines X-rays through the crystal. Unlike a single dental X-ray, which produces a shadow image of a tooth, these X-rays have to be taken many times from different angles to produce a pattern from the scattered light, a map of the intensity of the X-rays after they diffract through the crystal. The X-rays bounce off the electron clouds that form the outer structure of each atom. A flawed crystal will yield a blurry pattern; a well-ordered protein crystal yields a series of sharp diffraction patterns. From these patterns, researchers build an electron density map. With powerful computers and a lot of calculations, scientists can use the electron density patterns to determine the structure of the protein and make a computer-generated model of the structure. The models let researchers improve their understanding of how the protein functions. They also allow scientists to look for receptor sites and active areas that control a protein's function and role in the progress of diseases. From there, pharmaceutical researchers can design molecules that fit the active site, much like a key and lock, so that the protein is locked without affecting the rest of the body. This is called structure-based drug design.

Development of X-ray excitable luminescent probes for scanning X-ray microscopy

International Nuclear Information System (INIS)

Moronne, M.M.

1999-01-01

Transmission soft X-ray microscopy is now capable of achieving resolutions that are typically 5 times better than the best-visible light microscopes. With expected improvements in zone plate optics, an additional factor of two may be realized within the next few years. Despite the high resolution now available with X-ray microscopes and the high X-ray contrast provided by biological molecules in the soft X-ray region (λ=2-5 nm), molecular probes for localizing specific biological targets have been lacking. To circumvent this problem, X-ray excitable molecular probes are needed that can target unique biological features. In this paper we report our initial results on the development of lanthanide-based fluorescent probes for biological labeling. Using scanning luminescence X-ray microscopy (SLXM, Jacobsen et al., J. Microscopy 172 (1993) 121-129), we show that lanthanide organo-polychelate complexes are sufficiently bright and radiation resistant to be the basis of a new class of X-ray excitable molecular probes capable of providing at least a fivefold improvement in resolution over visible light microscopy. Lanthanide probes, able to bind 80-100 metal ions per molecule, were found to give strong luminescent signals with X-ray doses exceeding 10 8 Gy, and were used to label actin stress fibers and in vitro preparations of polymerized tubulin. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

Projection-type X-ray microscope based on a spherical compound refractive X-ray lens

OpenAIRE

Dudchik, Yu. I.; Gary, C. K.; Park, H.; Pantell, R. H.; Piestrup, M. A.

2007-01-01

New projection- type X-ray microscope with a compound refractive lens as the optical element is presented. The microscope consists of an X-ray source that is 1-2 mm in diameter, compound X-ray lens and X-ray camera that are placed in-line to satisfy the lens formula. The lens forms an image of the X-ray source at camera sensitive plate. An object is placed between the X-ray source and the lens as close as possible to the source, and the camera shows a shadow image of the object. Spatial resol...

X-Ray Lasers 2016

CERN Document Server

Bulanov, Sergei; Daido, Hiroyuki; Kato, Yoshiaki

2018-01-01

These proceedings comprise a selection of invited and contributed papers presented at the 15th International Conference on X-Ray Lasers (ICXRL 2016), held at the Nara Kasugano International Forum, Japan, from May 22 to 27, 2016. This conference was part of an ongoing series dedicated to recent developments in the science and technology of x-ray lasers and other coherent x-ray sources with additional focus on supporting technologies, instrumentation and applications.   The book showcases recent advances in the generation of intense, coherent x-rays, the development of practical devices and their applications across a wide variety of fields. It also discusses emerging topics such as plasma-based x-ray lasers, 4th generation accelerator-based sources and higher harmonic generations, as well as other x-ray generation schemes.

The Mapping X-ray Fluorescence Spectrometer (MapX)

Science.gov (United States)

Sarrazin, P.; Blake, D. F.; Marchis, F.; Bristow, T.; Thompson, K.

2017-12-01

Many planetary surface processes leave traces of their actions as features in the size range 10s to 100s of microns. The Mapping X-ray Fluorescence Spectrometer (MapX) will provide elemental imaging at 100 micron spatial resolution, yielding elemental chemistry at a scale where many relict physical, chemical, or biological features can be imaged and interpreted in ancient rocks on planetary bodies and planetesimals. MapX is an arm-based instrument positioned on a rock or regolith with touch sensors. During an analysis, an X-ray source (tube or radioisotope) bombards the sample with X-rays or alpha-particles / gamma-rays, resulting in sample X-ray Fluorescence (XRF). X-rays emitted in the direction of an X-ray sensitive CCD imager pass through a 1:1 focusing lens (X-ray micro-pore Optic (MPO)) that projects a spatially resolved image of the X-rays onto the CCD. The CCD is operated in single photon counting mode so that the energies and positions of individual X-ray photons are recorded. In a single analysis, several thousand frames are both stored and processed in real-time. Higher level data products include single-element maps with a lateral spatial resolution of 100 microns and quantitative XRF spectra from ground- or instrument- selected Regions of Interest (ROI). XRF spectra from ROI are compared with known rock and mineral compositions to extrapolate the data to rock types and putative mineralogies. When applied to airless bodies and implemented with an appropriate radioisotope source for alpha-particle excitation, MapX will be able to analyze biogenic elements C, N, O, P, S, in addition to the cations of the rock-forming elements >Na, accessible with either X-ray or gamma-ray excitation. The MapX concept has been demonstrated with a series of lab-based prototypes and is currently under refinement and TRL maturation.

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.

Wavelength dispersive X-ray absorption fine structure imaging by parametric X-ray radiation

International Nuclear Information System (INIS)

Inagaki, Manabu; Sakai, Takeshi; Sato, Isamu; Hayakawa, Yasushi; Nogami, Kyoko; Tanaka, Toshinari; Hayakawa, Ken; Nakao, Keisuke

2008-01-01

The parametric X-ray radiation (PXR) generator system at Laboratory for Electron Beam Research and Application (LEBRA) in Nihon University is a monochromatic and coherent X-ray source with horizontal wavelength dispersion. The energy definition of the X-rays, which depends on the horizontal size of the incident electron beam on the generator target crystal, has been investigated experimentally by measuring the X-ray absorption near edge structure (XANES) spectra on Cu and CuO associated with conventional X-ray absorption imaging technique. The result demonstrated the controllability of the spectrum resolution of XANES by adjusting of the horizontal electron beam size on the target crystal. The XANES spectra were obtained with energy resolution of several eV at the narrowest case, which is in qualitative agreement with the energy definition of the PXR X-rays evaluated from geometrical consideration. The result also suggested that the wavelength dispersive X-ray absorption fine structure measurement associated with imaging technique is one of the promising applications of PXR. (author)

Bone X-Ray (Radiography)

Medline Plus

Full Text Available ... are the limitations of Bone X-ray (Radiography)? What is Bone X-ray (Radiography)? An x-ray ( ... leg (shin), ankle or foot. top of page What are some common uses of the procedure? A ...

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 ...

Bone X-Ray (Radiography)

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Full Text Available ... that might interfere with the x-ray images. Women should always inform their physician and x-ray ... Safety page for more information about radiation dose. Women should always inform their physician or x-ray ...

Bone X-Ray (Radiography)

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Full Text Available ... of knee x-rays. A portable x-ray machine is a compact apparatus that can be taken ... of the body being examined, an x-ray machine produces a small burst of radiation that passes ...

Bone X-Ray (Radiography)

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Full Text Available ... drawer under the table holds the x-ray film or image recording plate . Sometimes the x-ray ... extended over the patient while an x-ray film holder or image recording plate is placed beneath ...

X-ray holography

International Nuclear Information System (INIS)

Faigel, G.; Tegze, M.; Belakhovsky, M.; Marchesini, S.; Bortel, G.

2003-01-01

In the last decade holographic methods using hard X-rays were developed. They are able to resolve atomic distances, and can give the 3D arrangement of atoms around a selected element. Therefore, hard X-ray holography has potential applications in chemistry, biology and physics. In this article we give a general description of these methods and discuss the developments in the experimental technique. The capabilities of hard X-ray holography are demonstrated by examples

Operating Modes and Cooling Capabilities of the 3-Stage ADR Developed for the Soft-X-Ray Spectrometer Instrument on Astro-H

Science.gov (United States)

Shirron, Peter J.; Kimball, Mark O.; James, Bryan L.; Muench, Theo; DiPirro, Michael J.; Letmate, Richard V.; Sampson, Michael A.; Bialas, Tom G.; Sneiderman, Gary A.; Porter, Frederick S.;

Wide-area phase-contrast X-ray imaging using large X-ray interferometers

Energy Technology Data Exchange (ETDEWEB)

Momose, Atsushi E-mail: momose@exp.t.u-tokyo.ac.jp; Takeda, Tohoru; Yoneyama, Akio; Koyama, Ichiro; Itai, Yuji

2001-07-21

Large X-ray interferometers are developed for phase-contrast X-ray imaging aiming at medical applications. A monolithic X-ray interferometer and a separate one are studied, and currently a 25 mmx20 mm view area can be generated. This paper describes the strategy of our research program and some recent developments.

Wide-area phase-contrast X-ray imaging using large X-ray interferometers

Science.gov (United States)

Momose, Atsushi; Takeda, Tohoru; Yoneyama, Akio; Koyama, Ichiro; Itai, Yuji

2001-07-01

Large X-ray interferometers are developed for phase-contrast X-ray imaging aiming at medical applications. A monolithic X-ray interferometer and a separate one are studied, and currently a 25 mm×20 mm view area can be generated. This paper describes the strategy of our research program and some recent developments.

Bone X-Ray (Radiography)

Medline Plus

Full Text Available ... x-rays. top of page What does the equipment look like? The equipment typically used for bone x-rays consists of ... and joint abnormalities, such as arthritis. X-ray equipment is relatively inexpensive and widely available in emergency ...

Material Discriminated X-Ray CT System by Using New X-Ray Imager with Energy Discriminate Function

Directory of Open Access Journals (Sweden)

Toru Aoki

2008-04-01

Full Text Available Material discriminated X-ray CT system has been constructed by using conventional X-ray tube (white X-ray source and photon-counting X-ray imager as an application with energy band detection. We have already reported material identify X-ray CT using K-shell edge method elsewhere. In this report the principle of material discrimination was adapted the separation of electron-density and atomic number from attenuation coefficient mapping in X-ray CT reconstructed image in two wavelength X-ray CT method using white X-ray source and energy discriminated X-ray imager by using two monochrome X-ray source method. The measurement phantom was prepared as four kinds material rods (Carbon(C, Iron(Fe, Copper(Cu, Titanium(Ti rods of 3mm-diameter inside an aluminum(Al rod of 20mm-diameter. We could observed material discriminated X-ray CT reconstructed image, however, the discrimination properties were not good than two monochrome X-ray CT method. This results was could be explained because X-ray scattering, beam-hardening and so on based on white X-ray source, which could not observe in two monochrome X-ray CT method. However, since our developed CdTe imager can be detect five energy-bands at the same time, we can use multi-band analysis to decrease the least square error margin. We will be able to obtain more high separation in atomic number mapping in X-ray CT reconstructed image by using this system.

X-Pinch And Its Applications In X-ray Radiograph

International Nuclear Information System (INIS)

Zou Xiaobing; Wang Xinxin; Liu Rui; Zhao Tong; Zeng Naigong; Zhao Yongchao; Du Yanqiang

2009-01-01

An X-pinch device and the related diagnostics of x-ray emission from X-pinch were briefly described. The time-resolved x-ray measurements with photoconducting diodes show that the x-ray pulse usually consists of two subnanosecond peaks with a time interval of about 0.5 ns. Being consistent with these two peaks of the x-ray pulse, two point x-ray sources of size ranging from 100 μm to 5 μm and depending on cut-off x-ray photon energy were usually observed on the pinhole pictures. The x-pinch was used as x-ray source for backlighting of the electrical explosion of single wire and the evolution of X-pinch, and for phase-contrast imaging of soft biological objects such as a small shrimp and a mosquito.

Two New Types of Detector for X- or Gamma-Ray Cameras

International Nuclear Information System (INIS)

Kellershohn, C.; Desgrez, A.; Lansiart, A.

1964-01-01

X- or γ-ray cameras consist essentially of a hole-type or grid-type lens system together with a detector. The authors propose two kinds of detector quite different from the Anger device, which so far has been the only one in practical use. The first consists of a self-triggering spark chamber. This chamber, about 20 cm in diam. and filled with a rare gas (argon or xenon), forms a cathode and two grids. The cathode and the second grid are subjected to a potential difference of several kilovolts, somewhat lower than the breakdown voltage. The first cathode-grid space serves as an electron source under the action of the low-energy X- or γ-ray photons. The cathode can also be plated with a metal of high Z, or a crystal scintillator connected to a photocathode can be used. After suitable amplification, the sudden burst of charges due to electron multiplication in the Townsend avalanche produces a well localized spark with a delay of a fraction of a microsecond. The image is obtained with the aid of a camera whose shutter is permanently open. The second type of detector consists of a Csl (Tl) crystal connected to the photocathode of a Thomson tube, 20 cm in diam. and with electrostatic focusing. The image on the secondary screen of this tube is transferred by an optical device to the photocathode of a tube with parallel electric and magnetic field (manufactured by the English Electric Valve Company) and serving as shutter. Some of the light entering the optical device is received by a photomultiplier, which controls the opening of the shutter tube through an amplitude selector. This arrangement makes it possible to distinguish between the light due to the signal and that due to the noise of the Thomson tube. The shutter tube is opened only by the former. Since the shutter tube remains open for only an extremely short time, the signal-noise ratio of this detector arrangement is high enough to give an image on the end screen of the shutter tube using a permanently open

Chest X-Ray (Chest Radiography)

Science.gov (United States)

... Resources Professions Site Index A-Z X-ray (Radiography) - Chest Chest x-ray uses a very small dose ... Radiography? What is a Chest X-ray (Chest Radiography)? The chest x-ray is the most commonly performed diagnostic ...

Thomson scattering on the PRETEXT Tokamak

International Nuclear Information System (INIS)

McCool, S.C.

1982-03-01

Ruby laser Thomson scattering was performed on the PRETEXT tokamak. A 10 Joule Q-switched laser and a 1 meter 10 channel polychromator were used to diagnose the electron temperature and density profiles in the PRETEXT plasma. These parameters were measured as a function of time and radial position on a shot to shot basis. The density measurement was calibrated by Rayleigh and Raman scattering and by comparison with data from a 4 mm microwave interferometer. Electron densities ranging from 1 x 10 12 cm -3 to 2 x 10 13 cm -3 and temperatures ranging from 3 eV to 400 eV were observed. Detailed measurements were made throughout the 40 ms discharge with particular emphasis on the current rise phase. The Thomson scattering data was used as input to a one dimensional magnetic diffusion code. This code modelled the evolution of the current density and safety factor profiles. The results of this analysis were compared with existing theories of tokamak current penetration. The growth of resitive MHD tearing modes was proposed as a likely explanation for the anomalously rapid current penetration observed in PRETEXT

X-ray luminescent glasses

International Nuclear Information System (INIS)

Takahashi, T.; Yamada, O.

1981-01-01

X-ray luminescent glasses comprising a divalent cation such as an alkaline earth metal or other divalent cations such as pb, cd, or zn, and certain rare earth metaphosphates are suitable as vitreous, x-ray phosphors or x-ray luminescent glass fibers in an x-ray intensifying screen. The glasses have the composition n(Mo X p2o5)((1-y)tb2o3 X yce2o3 X 3p2o5) wherein N is greater than zero but less than or equal to 16, M is an alkaline earth metal or other divalent cation such as pb, cd, or zn, and Y is greater than or equal to zero but less than one

X-ray electromagnetic application technology

International Nuclear Information System (INIS)

2011-01-01

The investigating committee aimed at research on electromagnetic fields in functional devices and X-ray fibers for efficient coherent X-ray generation and their material science, high-precision manufacturing, particularly for X-ray electromagnetic application technology from January 2006 to December 2008. In this report, we describe our research results, in particular, on the topics of synchrotron radiation and free-electron laser, Saga Synchrotron Project, X-ray waveguides and waveguide-based lens-less hard-X-ray imaging, X-ray nanofocusing for capillaries and zone plates, dispersion characteristics in photonics crystal consisting of periodic atoms for nanometer waveguides, electromagnetic characteristics of grid structures for scattering fields of nano-meter electromagnetic waves and X-rays, FDTD parallel computing of fundamental scattering and attenuation characteristics of X-ray for medical imaging diagnosis, orthogonal relations of electromagnetic fields including evanescent field in dispersive medium. (author)

Legal directives in the X-ray regulation for the field of X-ray diagnostics

International Nuclear Information System (INIS)

Huhn, Walter

2012-01-01

The operation of each X-ray device is subject to the requirements of the X-ray regulations (RoeV); for different operational modes or applications like curative diagnostics, X-ray serial examinations, X-ray radiotherapy and teleradiology different directives exist and have to be respected. The report discusses the issues licensing and notification procedures, radiation protection representative, requirements for the commissioning (teleradiology, serial X.ray examinations), technical qualification and radiation protection knowledge of physicians, technical qualification of the assistant personnel.

High-speed X-ray topography

International Nuclear Information System (INIS)

Eckers, W.; Oppolzer, H.

1977-01-01

The investigation of lattice defects in semiconductor crystals by conventional X-ray diffraction topography is very time-consuming. Exposure times can be reduced by using high-intensity X-rays and X-ray image intensifiers. The described system comprises a high-power rotating-anode X-ray tube, a remote-controlled X-ray topography camera, and a television system operating with an X-ray sensing VIDICON. System performance is demonstrated with reference to exploratory examples. The exposure time for photographic plates is reduced to 1/20 and for the X-ray TV system (resolution of the order of 30 μm) to 1/100 relative to that required when using a conventional topography system. (orig.) [de

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.

Effects of X-ray tube parameters on thickness measure precision in X-ray profile gauge

International Nuclear Information System (INIS)

Miao Jichen; Wu Zhifang; Xing Guilai

2011-01-01

Instantaneous profile gauge technology has been widely used in metallurgy industry because it can on-line get the profile of steel strip. It has characters of high measure precision and wide measure range, but the X-ray tube parameters only can be set few different values during measurement. The relations of thickness measure precision and X-ray tube current, X-ray tube voltage were analyzed. The results show that the X-ray tube current affects the thickness measure precision and the X-ray tube voltage determines the thickness measure range. The method of estimating the X-ray current by thickness measure precision was provided in the end. This method is the base of X-ray source selection and X-ray source parameter's setting in the instantaneous profile gauge. (authors)

Bone X-Ray (Radiography)

Medline Plus

Full Text Available ... X-rays are a form of radiation like light or radio waves. X-rays pass through most objects, including the body. Once it is carefully aimed at the part of the body being examined, an x-ray machine produces a small ...

X-Ray Exam: Hip

Science.gov (United States)

... for Educators Search English Español X-Ray Exam: Hip KidsHealth / For Parents / X-Ray Exam: Hip What's in this article? What It Is Why ... You Have Questions Print What It Is A hip X-ray is a safe and painless test ...

X-Ray Exam: Ankle

Science.gov (United States)

... for Educators Search English Español X-Ray Exam: Ankle KidsHealth / For Parents / X-Ray Exam: Ankle What's in this article? What It Is Why ... You Have Questions Print What It Is An ankle X-ray is a safe and painless test ...

Shield device for controlling the dose of x-rays applied in an x-ray machine

International Nuclear Information System (INIS)

Charrier, P.

1983-01-01

This invention provides an improved shield for use with an x-ray machine. The shield can control the dose of x-rays applied by the machine in different areas without affecting the power of the x-rays. This is achieved with a shield especially designed and positioned to intercept with x-rays for longer or shorter periods in different areas during the taking of the picture, but not for the whole period of time necessary for taking this picture. Each area of the subject being x-rayed is exposed to full power x-rays. However, owing to the shield, the areas that require smaller dose receive these full power x-rays for a shorter portion of the time required to take the picture while the other areas that require larger dose of x-rays, receive the full power x-rays for a longer portion of the full period of time required to take the picture. To ensure this differential exposure, the shield is placed through the path of the x-rays and rotated about an axis which is generally transverse to the direction of travel of the x-rays to cut out some of said x-rays for different portions of the period of time necessary for taking the picture. The shield is preferably shaped to intercept x-rays for a longer period in some areas than in others depending on the required doses. A plurality of differently shaped shields can be provided to suit different picture taking situations

X-Ray Exam: Cervical Spine

Science.gov (United States)

... Staying Safe Videos for Educators Search English Español X-Ray Exam: Cervical Spine KidsHealth / For Parents / X-Ray ... MRI): Lumbar Spine Broken Bones Getting an X-ray (Video) X-Ray (Video) View more Partner Message About Us ...

Differences of X-ray exposure between X-ray diagnostics with a conventional X-ray screen-system and with an image-intensifier-television-unit

International Nuclear Information System (INIS)

Loehr, H.; Vogel, H.; Reinhart, J.; Jantzen, R.

1977-01-01

During X-ray diagnostics of patients in the II. Medizinische Poliklinik the X-ray exposure was determined. It corresponded to the data described in literature. Two groups were compared: 518 patients examined with a conventional X-ray screen-system and 642 patients examined with an image-intensifier-television-system. The results demonstrated that with exception of thoracical X-ray examination the replacing of the old system by the television system brought a remarkable increase of the X-ray exposure. The doses depended of the patients constitution to a high degree. (orig.) [de

Applications of phase-contrast x-ray imaging to medicine using an x-ray interferometer

Science.gov (United States)

Momose, Atsushi; Yoneyama, Akio; Takeda, Tohoru; Itai, Yuji; Tu, Jinhong; Hirano, Keiichi

1999-10-01

We are investigating possible medical applications of phase- contrast X-ray imaging using an X-ray interferometer. This paper introduces the strategy of the research project and the present status. The main subject is to broaden the observation area to enable in vivo observation. For this purpose, large X-ray interferometers were developed, and 2.5 cm X 1.5 cm interference patterns were generated using synchrotron X-rays. An improvement of the spatial resolution is also included in the project, and an X-ray interferometer designed for high-resolution phase-contrast X-ray imaging was fabricated and tested. In parallel with the instrumental developments, various soft tissues are observed by phase- contrast X-ray CT to find correspondence between the generated contrast and our histological knowledge. The observation done so far suggests that cancerous tissues are differentiated from normal tissues and that blood can produce phase contrast. Furthermore, this project includes exploring materials that modulate phase contrast for selective imaging.

X-ray spectral meter of high voltages for X-ray apparatuses

International Nuclear Information System (INIS)

Zubkov, I.P.; Larchikov, Yu.V.

1993-01-01

Design of the X-ray spectral meter of high voltages (XRSMHV) for medical X-ray apparatuses permitting to conduct the voltage measurements without connection to current circuits. The XRSMHV consists of two main units: the detector unit based on semiconductor detector and the LP4900B multichannel analyzer (Afora, Finland). The XRSMYV was tested using the pilot plant based on RUM-20 X-ray diagnostic apparatus with high-voltage regulator. It was shown that the developed XRSMHV could be certify in the range of high constant voltages form 40 up to 120 kV with the basic relative error limits ±0.15%. The XRSMHV is used at present as the reference means for calibration of high-voltage medical X-ray equipment

Feasibility of using continuous X-ray to simulate cable response under X-ray environment

International Nuclear Information System (INIS)

Ma Liang; Zhou Hui; Cheng Yinhui; Wu Wei; Li Jinxi; Zhao Mo; Guo Jinghai

2014-01-01

The mechanism and simulating method of cable response induced by X-ray were researched, and the relationship of cable response irradiated by continuous and pulsed X-ray was analyzed. A one-dimension model of strip line irradiation response of X-ray was given, which includes the gap between cable shield and dielectric, and induced conductivity in cable dielectric. The calculation result using the model indicates that the cable responses of continuous and rectangular-pulsed X-ray have the similar current waveform and the same gap voltages. Therefore, continuous X-ray can be used to research some cable responses of pulsed X-ray irradiation under the mechanism described in the one-dimension model. (authors)

X-ray cardiovascular examination apparatus

International Nuclear Information System (INIS)

1977-01-01

An X-ray source is mounted in an enclosure for angulating longitudinally about a horizontal axis. An X-ray-permeable, patient-supporting table is mounted on the top of the enclosure for executing lateral and longitudinal movements. An X-ray image-receiving device such as an X-ray image intensifier is mounted above the table on a vertically movable arm which is on a longitudinally movable carriage. Electric control means are provided for angulating the X-ray source and image intensifier synchronously as the image intensifier system is shifted longitudinally or vertically such that the central ray from the X-ray source is kept intensifier

Effect of Electric Voltage and Current of X-ray Chamber on the Element inthe Zirconium Alloy Analysis X-ray by X-ray Fluorescence

International Nuclear Information System (INIS)

Yusuf-Nampira; Narko-Wibowo, L; Rosika-Krisnawati; Nudia-Barenzani

2000-01-01

The using of x-ray fluorescence in the chemical analysis depend heavilyon the parameters of x-ray chamber, for examples : electric voltage andelectric current. That parameter give effect in the result of determine ofSn, Cr, Fe and Ni in the zirconium alloy. 20 kV electric voltages are used onthe Mo x-ray chamber shall product x-ray of zirconium in the sample materialcan give effect in the stability of the analysis result (deviation more than5%). The result of analysis of elements in the zirconium alloy shall givedeviation less than 5% when using of electric voltage of the x-ray chamberless than 19 kV. The sensitivity of analysis can be reached by step upelectric current of x-ray chamber. (author)

Compound refractive X-ray lens

International Nuclear Information System (INIS)

Nygren, D.R.; Cahn, R.; Cederstrom, B.; Danielsson, M.; Vestlund, J.

2000-01-01

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

Compound refractive X-ray lens

Science.gov (United States)

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

2000-01-01

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

X-ray diffraction device comprising cooling medium connections provided on the x-ray tube

NARCIS (Netherlands)

1996-01-01

An X-ray diffraction device comprises a water-cooled X-ray tube which exhibits a line focus as well as, after rotation through 90 DEG , a point focus. Contrary to customary X-ray tubes, the cooling water is not supplied via the housing (12) in which the X-ray tube is mounted, but the cooling water

X-ray hot plasma diagnostics

International Nuclear Information System (INIS)

Cojocaru, E.

1984-11-01

X-ray plasma emission study is powerful diagnostic tool of hot plasmas. In this review article the main techniques of X-ray plasma emission measurement are shortly presented: X-ray spectrometry using absorbent filters, crystal and grating spectrometers, imaging techniques using pinhole cameras, X-ray microscopes and Fresnel zone plate cameras, X-ray plasma emission calorimetry. Advances in these techniques with examples for different hot plasma devices are also presentes. (author)

76 FR 27365 - West, A Thomson Reuters Business, Thomson Reuters Legal Division, Including On-Site Leased...

Science.gov (United States)

2011-05-11

... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-75,099] West, A Thomson Reuters Business, Thomson Reuters Legal Division, Including On-Site Leased Workers From ADECCO, Albuquerque, NM... Adjustment Assistance (TAA) applicable to workers and former workers of West, A Thomson Reuters Business...

Chest X-Ray

Medline Plus

Full Text Available ... some concerns about chest x-rays. However, it’s important to consider the likelihood of benefit to your health. While a chest x-ray use a ... posted: How to Obtain and Share ...

Soft x-ray streak cameras

International Nuclear Information System (INIS)

Stradling, G.L.

1988-01-01

This paper is a discussion of the development and of the current state of the art in picosecond soft x-ray streak camera technology. Accomplishments from a number of institutions are discussed. X-ray streak cameras vary from standard visible streak camera designs in the use of an x-ray transmitting window and an x-ray sensitive photocathode. The spectral sensitivity range of these instruments includes portions of the near UV and extends from the subkilovolt x- ray region to several tens of kilovolts. Attendant challenges encountered in the design and use of x-ray streak cameras include the accommodation of high-voltage and vacuum requirements, as well as manipulation of a photocathode structure which is often fragile. The x-ray transmitting window is generally too fragile to withstand atmospheric pressure, necessitating active vacuum pumping and a vacuum line of sight to the x-ray signal source. Because of the difficulty of manipulating x-ray beams with conventional optics, as is done with visible light, the size of the photocathode sensing area, access to the front of the tube, the ability to insert the streak tube into a vacuum chamber and the capability to trigger the sweep with very short internal delay times are issues uniquely relevant to x-ray streak camera use. The physics of electron imaging may place more stringent limitations on the temporal and spatial resolution obtainable with x-ray photocathodes than with the visible counterpart. Other issues which are common to the entire streak camera community also concern the x-ray streak camera users and manufacturers

Disappearance of the laue spots of the downward X-ray diffraction and huge recoil Thomson scattering in solid helium as some prominent peculiarities of a quantum crystal

Energy Technology Data Exchange (ETDEWEB)

Nakajima, Tetsuo

1996-02-01

In topographs of the downward X-ray diffraction, no Laue spots could be observed using a horizontally thin line-focussed beam. The disappearance of the Laue spots by the downward X-ray diffraction could be explained by two main factors besides a synergistic effect of the smallness of the atomic-scattering factors, the absorption coefficients, the densities etc. One is that the downward X-ray diffraction is completely inelastic scattering, and, as a result, diffracted X-ray beams may become entirely diffuse scattering. The other is that the great difference in the linear scatterer density between the forward and downward directions resulted from the fact that the irradiation of a line-focussed X-ray beam to take section topographs weakens the downward X-ray diffraction. The main reason is not due to the zero-point vibration. (J.P.N.).

Disappearance of the laue spots of the downward X-ray diffraction and huge recoil Thomson scattering in solid helium as some prominent peculiarities of a quantum crystal

International Nuclear Information System (INIS)

Nakajima, Tetsuo.

1996-02-01

In topographs of the downward X-ray diffraction, no Laue spots could be observed using a horizontally thin line-focussed beam. The disappearance of the Laue spots by the downward X-ray diffraction could be explained by two main factors besides a synergistic effect of the smallness of the atomic-scattering factors, the absorption coefficients, the densities etc. One is that the downward X-ray diffraction is completely inelastic scattering, and, as a result, diffracted X-ray beams may become entirely diffuse scattering. The other is that the great difference in the linear scatterer density between the forward and downward directions resulted from the fact that the irradiation of a line-focussed X-ray beam to take section topographs weakens the downward X-ray diffraction. The main reason is not due to the zero-point vibration. (J.P.N.)

Portable X-ray fluorescence analyzer of high sensitivity using X-ray tube excitation

International Nuclear Information System (INIS)

Vatai, E.; Ando, L.

1982-01-01

A review of the three main methods of X-ray fluorescence analysis and their problems is given. The attainable accuracy and effectiveness of each method are discussed. The main properties of portable X-ray analyzers required by the industry are described. The results and experiences of R and D activities in ATOMKI (Debrecen, Hungary) for developing portable X-ray analyzers are presented. The only way for increasing the accuracy and decreasing the measuring time is the application of X-ray tube excitation instead of radioactive sources. The new ATOMKI equipment presently under construction and patenting uses X-ray tube excitation; it will increase the accuracy of concentration determination by one order of magnitude. (D.Gy.)

X ray Production. Chapter 5

Energy Technology Data Exchange (ETDEWEB)

Nowotny, R. [Medical University of Vienna, Vienna (Austria)

2014-09-15

The differential absorption of X rays in tissues and organs, owing to their atomic composition, is the basis for the various imaging methods used in diagnostic radiology. The principles in the production of X rays have remained the same since their discovery. However, much refinement has gone into the design of X ray tubes to achieve the performance required for today’s radiological examinations. In this chapter, an outline of the principles of X ray production and a characterization of the radiation output of X ray tubes will be given. The basic processes producing X rays are dealt with in Section 1.4.

X-ray apparatus

International Nuclear Information System (INIS)

Sell, L.J.

1981-01-01

A diagnostic x-ray device, readily convertible between conventional radiographic and tomographic operating modes, is described. An improved drive system interconnects and drives the x-ray source and the imaging device through coordinated movements for tomography

X-ray astronomy 2000: Wide field X-ray monitoring with lobster-eye telescopes

International Nuclear Information System (INIS)

Inneman, A.; Hudec, R.; Pina, L.; Gorenstein, P.

2001-01-01

The recently available first prototypes of innovative very wide field X-ray telescopes of Lobster-Eye type confirm the feasibility to develop such flight instruments in a near future. These devices are expected to allow very wide field (more than 1000 square degrees) monitoring of the sky in X-rays (up to 10 keV and perhaps even more) with faint limits. We will discuss the recent status of the development of very wide field X-ray telescopes as well as related scientific questions including expected major contributions such as monitoring and study of X-ray afterglows of Gamma Ray Bursts

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

Energy Technology Data Exchange (ETDEWEB)

Seidler, G. T., E-mail: seidler@uw.edu; Mortensen, D. R.; Remesnik, A. J.; Pacold, J. I.; Ball, N. A.; Barry, N.; Styczinski, M.; Hoidn, O. R. [Physics Department, University of Washington, Seattle, Washington 98195-1560 (United States)

2014-11-15

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

Illumination system for X-ray lithography

International Nuclear Information System (INIS)

Buckley, W.D.

1989-01-01

An X-ray lithography system is described, comprising: a point source of X-Ray radiation; a wafer plane disposed in spaced relation to the point source of X-Ray radiation; a mask disposed between the point source of X-Ray radiation and the wafer plane whereby X-Ray radiation from the point source of X-ray radiation passes through the mask to the water plane; and X-Ray absorbent means mounted between the point source of X-Ray radiation and the wafer plane, the X-Ray absorbent means being of quadratically absorption from maximum absorption at the center to minimum absorption at the edge so as to have a radial absorption gradient profile to compensate for radial flux variation of the X-Ray radiation

An X-ray and optical study of the ultracompact X-ray binary A 1246-58

NARCIS (Netherlands)

in 't Zand, J.J.M.; Bassa, C.G.; Jonker, P.G.; Keek, L.; Verbunt, F.W.M.; Méndez, M.; Markwardt, C.B.

2008-01-01

Results are discussed of an X-ray and optical observation campaign of the low-mass X-ray binary A 1246-58 performed with instruments on Satellite per Astronomia X ("BeppoSAX"), the Rossi X-ray Timing Explorer (RXTE), the X-ray Multi-mirror Mission ("XMM-Newton"), the Swift mission, and the Very

X-ray - skeleton

Science.gov (United States)

... this page: //medlineplus.gov/ency/article/003381.htm X-ray - skeleton To use the sharing features on this ... Degenerative bone conditions Osteomyelitis Risks There is low radiation exposure. X-rays machines are set to provide the smallest ...

Extremity x-ray

Science.gov (United States)

... page: //medlineplus.gov/ency/article/003461.htm Extremity x-ray To use the sharing features on this page, ... in the body Risks There is low-level radiation exposure. X-rays are monitored and regulated to provide the ...

Chest X-Ray

Medline Plus

Full Text Available ... X-ray Transcript Welcome to Radiology Info dot org! Hello, I’m Dr. Geoffrey Rubin, a radiologist ... about chest x-rays, visit Radiology Info dot org. Thank you for your time! Spotlight Recently posted: ...

Bone X-Ray (Radiography)

Medline Plus

Full Text Available ... The x-ray tube is connected to a flexible arm that is extended over the patient while an x-ray film holder or image recording plate is placed beneath the patient. top of page How does the procedure work? X-rays are a form of radiation like ...

X-ray Absorption Spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Yano, Junko; Yachandra, Vittal K.

2009-07-09

This review gives a brief description of the theory and application of X-ray absorption spectroscopy, both X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS), especially, pertaining to photosynthesis. The advantages and limitations of the methods are discussed. Recent advances in extended EXAFS and polarized EXAFS using oriented membranes and single crystals are explained. Developments in theory in understanding the XANES spectra are described. The application of X-ray absorption spectroscopy to the study of the Mn4Ca cluster in Photosystem II is presented.

X-ray filtration apparatus

International Nuclear Information System (INIS)

Thompson, G.

1992-01-01

This invention relates to an X-ray shielding support device. In spite of considerable development in X-ray taking techniques, a need still exists for effective shielding, inter alia, to compensate for variations in the thickness, density and the absorption properties of the object being studied. By appropriate shielding, the X-ray image produced is of sufficient detail, contrast and intensity over its entire area to constitute a useful diagnostic aid. It is also desirable to subject the patient to the smallest possible X-ray dosage. 4 figs

Phase-contrast X-ray CT

Energy Technology Data Exchange (ETDEWEB)

Momose, Atsushi [Hitachi Ltd., Saitama (Japan). Advanced Research Laboratory; Takeda, Tohoru; Itai, Yuji

1995-12-01

Phase-contrast X-ray computed tomography (CT) enabling the observation of biological soft tissues without contrast enhancement has been developed. The X-ray phase shift caused by an object is measured and input to a standard CT reconstruction algorithm. A thousand times increase in the image sensitivity to soft tissues is achieved compared with the conventional CT using absorption contrast. This is because the X-ray phase shift cross section of light elements is about a thousand times larger than the absorption cross section. The phase shift is detected using an X-ray interferometer and computer analyses of interference patterns. Experiments were performed using a synchrotron X-ray source. Excellent image sensitivity is demonstrated in the observation of cancerous rabbit liver. The CT images distinguish cancer lesion from normal liver tissue and, moreover, visualize the pathological condition in the lesion. Although the X-ray energy employed and the present observation area size are not suitable for medical applications as they are, phase-contrast X-ray CT is promising for investigating the internal structure of soft tissue which is almost transparent for X-rays. The high sensitivity also provides the advantage of reducing X-ray doses. (author).

Symbiotic Stars in X-rays

Science.gov (United States)

Luna, G. J. M.; Sokoloski, J. L.; Mukai, K.; Nelson, T.

2014-01-01

Until recently, symbiotic binary systems in which a white dwarf accretes from a red giant were thought to be mainly a soft X-ray population. Here we describe the detection with the X-ray Telescope (XRT) on the Swift satellite of 9 white dwarf symbiotics that were not previously known to be X-ray sources and one that was previously detected as a supersoft X-ray source. The 9 new X-ray detections were the result of a survey of 41 symbiotic stars, and they increase the number of symbiotic stars known to be X-ray sources by approximately 30%. Swift/XRT detected all of the new X-ray sources at energies greater than 2 keV. Their X-ray spectra are consistent with thermal emission and fall naturally into three distinct groups. The first group contains those sources with a single, highly absorbed hard component, which we identify as probably coming from an accretion-disk boundary layer. The second group is composed of those sources with a single, soft X-ray spectral component, which likely arises in a region where low-velocity shocks produce X-ray emission, i.e. a colliding-wind region. The third group consists of those sources with both hard and soft X-ray spectral components. We also find that unlike in the optical, where rapid, stochastic brightness variations from the accretion disk typically are not seen, detectable UV flickering is a common property of symbiotic stars. Supporting our physical interpretation of the two X-ray spectral components, simultaneous Swift UV photometry shows that symbiotic stars with harder X-ray emission tend to have stronger UV flickering, which is usually associated with accretion through a disk. To place these new observations in the context of previous work on X-ray emission from symbiotic stars, we modified and extended the alpha/beta/gamma classification scheme for symbiotic-star X-ray spectra that was introduced by Muerset et al. based upon observations with the ROSAT satellite, to include a new sigma classification for sources with

X-ray apparatus

International Nuclear Information System (INIS)

Bernstein, S.; Stagg, L.; Lambert, T.W.; Griswa, P.J.

1976-01-01

A patient support system for X-ray equipment in arteriographic studies of the heart is described in detail. The support system has been designed to overcome many of the practical problems encountered in using previous types of arteriographic X-ray equipment. The support system is capable of horizontal movement and, by a series of shafts attached to the main support system, the X-ray source and image intensifier or detector may be rotated through the same angle. The system is highly flexible and details are given of several possible operational modes. (U.K.)

Comparative study of radiation dose between digital panoramic X-ray unit and general panoramic X-ray unit

International Nuclear Information System (INIS)

Li Qingshan; Duan Tao; Wang Xiaoyun; Zhao Li; Dong Jian; Wei Lei

2010-01-01

Objective: To compare the actual dose of patients who receive the same medical practice by either digital panoramic X-ray unit and general panoramic X-ray unit and give evidence for better selection of oral X-ray examination method. Methods: Round sheet lithium fluoride (LiF) thermoluminescent dosimeters (TLD) were used. The experiment was divided into natural background contrast group, general panoramic X-ray children group, general panoramic X-ray adults group, digital panoramic X-ray children group and digital panoramic X-ray adults group. The dosimeter of natural background radiation was placed at the office of the doctor, the dosimeters of general panoramic X-ray children group and general panoramic X-ray adults group were irradiated by different conditions according to the clinical application of panoramic X-ray to children and adults, the dosimeters of digital panoramic X-ray children group and digital panoramic X-ray adults group were irradiated by different conditions according to the clinical application of digital panoramic X-ray to children and adults. The thermoluminescent dosimeter was used to count and calculate the exposure doses in various groups. Results: The dose of children exposed in general panoramic X-ray unit was 1.28 times of that in digital panoramic X-ray unit, there was significant difference (t=6.904, P<0.01). The dose of adults exposed in general panoramic X-ray unit was 1.55 times of that in the digital panoramic X-ray unit, there also was significant difference (t=-11.514. P< 0.01). Conclusion: The digital panoramic X-ray unit can reduce the dose of patients, so the digital panoramic X-ray unit should be used as far as possible. (authors)

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

X-ray astronomy

International Nuclear Information System (INIS)

Narayanan, M.S.

1976-01-01

The deployment of detectors outside the deleterious effects of the atmosphere by sending them in space vehicles, has been explained. This has thrown open the entire spectrum of the electromagnetic and particle radiation to direct observations, thus enlarging the vistas of the field of astronomy and astrophysics. The discovery of strong emitters of X-rays such as SCO X-1, NorX-2, transient sources such as Cen X-2, Cen X-4, Cen X-1, Supernova remnants Tan X-1, etc., are reported. The background of the X-ray spectrum as measured during two rocket flights over Thumba, India is presented. (K.B.)

Application of X-ray CCD camera in X-ray spot diagnosis of rod-pinch diode

International Nuclear Information System (INIS)

Song Yan; Zhou Ming; Song Guzhou; Ma Jiming; Duan Baojun; Han Changcai; Yao Zhiming

2015-01-01

The pinhole imaging technique is widely used in the measurement of X-ray spot of rod-pinch diode. The X-ray CCD camera, which was composed of film, fiber optic taper and CCD camera, was employed to replace the imaging system based on scintillator, lens and CCD camera in the diagnosis of X-ray spot. The resolution of the X-ray CCD camera was studied. The resolution is restricted by the film and is 5 lp/mm in the test with Pb resolution chart. The frequency is 1.5 lp/mm when the MTF is 0.5 in the test with edge image. The resolution tests indicate that the X-ray CCD camera can meet the requirement of the diagnosis of X-ray spot whose scale is about 1.5 mm when the pinhole imaging magnification is 0.5. At last, the image of X-ray spot was gained and the restoration was implemented in the diagnosis of X-ray spot of rod-pinch diode. (authors)

Scintillating ribbon x-ray detector

International Nuclear Information System (INIS)

Kinchen, B.E.; Rogers, A.

1995-01-01

A patent in the early 1970's by Aerojet Corporation in Sacramento, CA put forth the idea of using an array of scintillating fibers for x-ray detection and imaging. In about 1975, Pratt and Whitney Aircraft in East Hartford, CT designed and manufactured an imaging system based on the patent. The device was 1.75 in thick in the direction of the x-ray beam and about 4 in. by 4 in. square. The device was used with a 8 MeV x-ray source to image and measure internal clearances within operating aircraft, gas turbines engines. There are significant advantages of fiber optic detectors in x-ray detection. However, the advantages are often outweighed by the disadvantages. Two of the advantages of scintillating fiber optic x-ray detectors are: (1) high limiting spatial frequency -- between 20 and 25 lp/mm; and (2) excellent x-ray stopping power -- they can be made thick and retain spatial resolution. In traditional fiber optic detectors the x-rays are oriented parallel to the long axis of the fiber. For the scintillating ribbon x-ray sensor, the x-rays are oriented normal to the fiber long axis. This ribbon sensor technique has a number of advantages over the two current radiographic techniques digital x-radiography and x-ray film: The main advantage the ribbon has is size and shape. It can be as thin as 0.05 in., virtually any width or length, and flexible. Once positioned in a given location, 20 to 100 square inches of the object being inspected can be imaged with a single x-ray beam sweep. It is clear that conventional digital cameras do not lend themselves to placement between walls of aircraft structures or similar items requiring x-ray inspections. A prototype scintillating ribbon x-ray sensor has been fabricated and tested by Synergistic Detector Designs. Images were acquired on corrosion test panels of aluminum fabricated by Iowa State University

Center for X-Ray Optics, 1992

International Nuclear Information System (INIS)

1993-08-01

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

J J Thomson and the discovery of the electron

International Nuclear Information System (INIS)

Squires, Gordon

1997-01-01

This short biography describes the life of J.J. Thomson, head of the Cavendish Laboratory in Cambridge. His early life as well as his contributions to physics, including the discovery of the electron from his research on cathode rays in 1897 are included. The work of other contributors to the understanding of electron properties is also noted briefly. (UK)

JEM-X: The X-ray monitor on INTEGRAL

DEFF Research Database (Denmark)

Budtz-Jørgensen, Carl; Lund, Niels; Westergaard, Niels Jørgen Stenfeldt

2004-01-01

The INTEGRAL X-ray monitor, JEM-X, (together with the two gamma ray instruments, SPI and IBIS) provides simultaneous imaging with arcminute angular resolution in the 3-35 keV band. The good angular resolution and low energy response of JEM-X plays an important role in the detection and identifica......The INTEGRAL X-ray monitor, JEM-X, (together with the two gamma ray instruments, SPI and IBIS) provides simultaneous imaging with arcminute angular resolution in the 3-35 keV band. The good angular resolution and low energy response of JEM-X plays an important role in the detection...

X ray spectra of X Per. [oso-8 observations

Science.gov (United States)

Becker, R. H.; Boldt, E. A.; Holt, S. S.; Pravdo, S. H.; Robinson-Saba, J.; Serlemitsos, P. J.; Swank, J. H.

1978-01-01

The cosmic X-ray spectroscopy experiment on OSO-8 observed X Per for twenty days during two observations in Feb. 1976 and Feb. 1977. The spectrum of X Per varies in phase with its 13.9 min period, hardening significantly at X-ray minimum. Unlike other X-ray binary pulsar spectra, X Per's spectra do not exhibit iron line emission or strong absorption features. The data show no evidence for a 22 hour periodicity in the X-ray intensity of X Per. These results indicate that the X-ray emission from X Per may be originating from a neutron star in a low density region far from the optically identified Be star.

JEM-X: The X-ray monitor on INTEGRAL

DEFF Research Database (Denmark)

Lund, Niels; Budtz-Jørgensen, Carl; Westergaard, Niels Jørgen Stenfeldt

1999-01-01

and identification of gamma ray sources as well as in the analysis and scientific interpretation of the combined X-ray and gamma ray data. JEM-X is a coded aperture X-ray telescope consisting of two identical detectors. Each detector has a sensitive area of 500 cm(2), and views the sky (6.6 deg FOV, FWHM) through...

Accelerator-driven X-ray Sources

Energy Technology Data Exchange (ETDEWEB)

Nguyen, Dinh Cong [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2015-11-09

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

Effects of X-Ray Dose On Rhizosphere Studies Using X-Ray Computed Tomography

Science.gov (United States)

Zappala, Susan; Helliwell, Jonathan R.; Tracy, Saoirse R.; Mairhofer, Stefan; Sturrock, Craig J.; Pridmore, Tony; Bennett, Malcolm; Mooney, Sacha J.

2013-01-01

X-ray Computed Tomography (CT) is a non-destructive imaging technique originally designed for diagnostic medicine, which was adopted for rhizosphere and soil science applications in the early 1980s. X-ray CT enables researchers to simultaneously visualise and quantify the heterogeneous soil matrix of mineral grains, organic matter, air-filled pores and water-filled pores. Additionally, X-ray CT allows visualisation of plant roots in situ without the need for traditional invasive methods such as root washing. However, one routinely unreported aspect of X-ray CT is the potential effect of X-ray dose on the soil-borne microorganisms and plants in rhizosphere investigations. Here we aimed to i) highlight the need for more consistent reporting of X-ray CT parameters for dose to sample, ii) to provide an overview of previously reported impacts of X-rays on soil microorganisms and plant roots and iii) present new data investigating the response of plant roots and microbial communities to X-ray exposure. Fewer than 5% of the 126 publications included in the literature review contained sufficient information to calculate dose and only 2.4% of the publications explicitly state an estimate of dose received by each sample. We conducted a study involving rice roots growing in soil, observing no significant difference between the numbers of root tips, root volume and total root length in scanned versus unscanned samples. In parallel, a soil microbe experiment scanning samples over a total of 24 weeks observed no significant difference between the scanned and unscanned microbial biomass values. We conclude from the literature review and our own experiments that X-ray CT does not impact plant growth or soil microbial populations when employing a low level of dose (<30 Gy). However, the call for higher throughput X-ray CT means that doses that biological samples receive are likely to increase and thus should be closely monitored. PMID:23840640

Synchrotron x-ray fluorescence and extended x-ray absorption fine structure analysis

International Nuclear Information System (INIS)

Chen, J.R.; Gordon, B.M.; Hanson, A.L.; Jones, K.W.; Kraner, H.W.; Chao, E.C.T.; Minkin, J.A.

1984-01-01

The advent of dedicated synchrotron radiation sources has led to a significant increase in activity in many areas of science dealing with the interaction of x-rays with matter. Synchrotron radiation provides intense, linearly polarized, naturally collimated, continuously tunable photon beams, which are used to determine not only the elemental composition of a complex, polyatomic, dilute material but also the chemical form of the elements with improved accuracy. Examples of the application of synchrotron radiation include experiments in synchrotron x-ray fluorescence (SXRF) analysis and extended x-ray absorption fine structure (EXAFS) analysis. New synchrotron radiation x-ray microprobes for elemental analysis in the parts per billion range are under construction at several laboratories. 76 references, 24 figures

X-Rays, Pregnancy and You

Science.gov (United States)

... Emitting Products and Procedures Medical Imaging Medical X-ray Imaging X-Rays, Pregnancy and You Share Tweet Linkedin Pin it ... the decision with your doctor. What Kind of X-Rays Can Affect the Unborn Child? During most x- ...

Stellar X-ray sources

International Nuclear Information System (INIS)

Katz, J.I.; Washington Univ., St. Louis, MO

1988-01-01

I Review some of the salient accomplishments of X-rap studies of compact objects. Progress in this field has closely followed the improvement of observational methods, particularly in angular resolution and duration of exposure. Luminous compact X-ray sources are accreting neutron stars or black holes. Accreting neutron stars may have characteristic temporal signatures, but the only way to establish that an X-ray source is a black hole is to measure its mass. A rough phenomenological theory is succesful, but the transport of angular momentum in accretion flows is not onderstood. A number of interesting complications have been observed, including precessing accretion discs, X-ray bursts, and the acceleration of jets in SS433. Many puzzles remain unsolved, including the excitation of disc precession, the nature of the enigmatic A- and gamma-ray source Cyg X-3, the mechanism by which slowly spinning accreting neutron stars lose angular momentum, and the superabundance of X-ray sources in globular clusters. 41 refs.; 5 figs

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.

Toward Adaptive X-Ray Telescopes

Science.gov (United States)

O'Dell, Stephen L.; Atkins, Carolyn; Button, Tim W.; Cotroneo, Vincenzo; Davis, William N.; Doel, Peer; Feldman, Charlotte H.; Freeman, Mark D.; Gubarev, Mikhail V.; Kolodziejczak, Jeffrey J.;

A high-energy, high-flux source of gamma-rays from all-optical non-linear Thomson scattering

Energy Technology Data Exchange (ETDEWEB)

Corvan, D.J., E-mail: dcorvan01@qub.ac.uk; Zepf, M.; Sarri, G.

2016-09-01

γ-Ray sources are among the most fundamental experimental tools currently available to modern physics. As well as the obvious benefits to fundamental research, an ultra-bright source of γ-rays could form the foundation of scanning of shipping containers for special nuclear materials and provide the bases for new types of cancer therapy. However, for these applications to prove viable, γ-ray sources must become compact and relatively cheap to manufacture. In recent years, advances in laser technology have formed the cornerstone of optical sources of high energy electrons which already have been used to generate synchrotron radiation on a compact scale. Exploiting the scattering induced by a second laser, one can further enhance the energy and number of photons produced provided the problems of synchronisation and compact γ-ray detection are solved. Here, we report on the work that has been done in developing an all-optical and hence, compact non-linear Thomson scattering source, including the new methods of synchronisation and compact γ-ray detection. We present evidence of the generation of multi-MeV (maximum 16–18 MeV) and ultra-high brilliance (exceeding 10{sup 20} photons s{sup −1}mm{sup −2}mrad{sup −2} 0.1% BW at 15 MeV) γ-ray beams. These characteristics are appealing for the paramount practical applications mentioned above. - Highlights: • How synchrotron radiation can be produced in an all optical setting using laser-plasmas. • Generating high-energy, high-flux gamma ray beams. • Presenting results from a recent NLTS experimental campaign. • Reveal insight into the experimental techniques employed.

Charge collection and absorption-limited x-ray sensitivity of pixellated x-ray detectors

International Nuclear Information System (INIS)

Kabir, M. Zahangir; Kasap, S.O.

2004-01-01

The charge collection and absorption-limited x-ray sensitivity of a direct conversion pixellated x-ray detector operating in the presence of deep trapping of charge carriers is calculated using the Shockley-Ramo theorem and the weighting potential of the individual pixel. The sensitivity of a pixellated x-ray detector is analyzed in terms of normalized parameters; (a) the normalized x-ray absorption depth (absorption depth/photoconductor thickness), (b) normalized pixel width (pixel size/thickness), and (c) normalized carrier schubwegs (schubweg/thickness). The charge collection and absorption-limited sensitivity of pixellated x-ray detectors mainly depends on the transport properties (mobility and lifetime) of the charges that move towards the pixel electrodes and the extent of dependence increases with decreasing normalized pixel width. The x-ray sensitivity of smaller pixels may be higher or lower than that of larger pixels depending on the rate of electron and hole trapping and the bias polarity. The sensitivity of pixellated detectors can be improved by ensuring that the carrier with the higher mobility-lifetime product is drifted towards the pixel electrodes

X-ray interferometers

International Nuclear Information System (INIS)

Franks, A.

1980-01-01

An improved type of amplitude-division x-ray interferometer is described. The wavelength at which the interferometer can operate is variable, allowing the instrument to be used to measure x-ray wavelength, and the angle of inclination is variable for sample investigation. (U.K.)

X-ray lasers

CERN Document Server

Elton, Raymond C

2012-01-01

The first in its field, this book is both an introduction to x-ray lasers and a how-to guide for specialists. It provides new entrants and others interested in the field with a comprehensive overview and describes useful examples of analysis and experiments as background and guidance for researchers undertaking new laser designs. In one succinct volume, X-Ray Lasers collects the knowledge and experience gained in two decades of x-ray laser development and conveys the exciting challenges and possibilities still to come._Add on for longer version of blurb_M>The reader is first introduced

Topological X-Rays Revisited

Science.gov (United States)

Lynch, Mark

2012-01-01

We continue our study of topological X-rays begun in Lynch ["Topological X-rays and MRI's," iJMEST 33(3) (2002), pp. 389-392]. We modify our definition of a topological magnetic resonance imaging and give an affirmative answer to the question posed there: Can we identify a closed set in a box by defining X-rays to probe the interior and without…

X-ray tube

International Nuclear Information System (INIS)

Webley, R.S.

1975-01-01

The object of the invention described is to provide an X-ray tube providing a scanned X-ray output which does not require a scanned electron beam. This is obtained by an X-ray tube including an anode which is rotatable about an axis, and a source of a beam of energy, for example an electron beam, arranged to impinge on a surface of the anode to generate X-radiation substantially at the region of incidence on the anode surface. The anode is rotatable about the axis to move the region of incidence over the surface. The anode is so shaped that the rotation causes the region of incidence to move in a predetermined manner relative to fixed parts of the tube so that the generated X-radiation is scanned in a predetermined manner relative to the tube. (UK)

Upsurge of X-ray astronomy 230-

International Nuclear Information System (INIS)

Hudec, D.R.

1978-01-01

Instruments are described used for X-ray astronomy, namely X-ray detectors and X-ray telescopes. Unlike telescopes, the detectors do not comprise X-ray optics. A survey is given of the results obtained in solar and stellar X-ray astronomy and hypotheses are submitted on the origin of X radiation in the interstellar space. (J.B.)

Review of X-ray Tomography and X-ray Fluorescence Spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Shear, Trevor A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2017-03-16

This literature review will focus on both laboratory and synchrotron based X-ray tomography of materials and highlight the inner workings of these instruments. X-ray fluorescence spectroscopy will also be reviewed and applications of the tandem use of these techniques will be explored. The real world application of these techniques during the internship will also be discussed.

Transmission X-ray Diffraction (XRD) Patterns Relevant to the MSL Chemin Amorphous Component: Sulfates And Silicates

Science.gov (United States)

Morris, R. V.; Rampe, E. B.; Graff, T. G.; Archer, P. D., Jr.; Le, L.; Ming, D. W.; Sutter, B.

2015-01-01

The Mars Science Laboratory (MSL) CheMin instrument on the Curiosity rover is a transmission X-ray diffractometer (Co-Kalpha radiation source and a approx.5deg to approx.52deg 2theta range) where the analyzed powder samples are constrained to have discrete particle diameters XRD amorphous component. Estimates of amorphous component abundance, based on the XRD data itself and on mass-balance calculations using APXS data crystalline component chemistry derived from XRD data, martian meteorites, and/or stoichiometry [e.g., 6-9], range from approx.20 wt.% to approx.50 wt.% of bulk sample. The APXSbased calculations show that the amorphous component is rich in volatile elements (esp. SO3) and is not simply primary basaltic glass, which was used as a surrogate to model the broad band in the RN CheMin pattern. For RN, the entire volatile inventory (except minor anhydrite) is assigned to the amorphous component because no volatile-bearing crystalline phases were reported within detection limits [2]. For JK and CB, Fesaponite, basanite, and akaganeite are volatile-bearing crystalline components. Here we report transmission XRD patterns for sulfate and silicate phases relevant to interpretation of MSL-CheMin XRD amorphous components.

Exploring the X-Ray Universe

Science.gov (United States)

Seward, Frederick D.; Charles, Philip A.

1995-11-01

Exploring the X-Ray Universe describes the view of the stars and galaxies that is obtained through X-ray telescopes. X-rays, which are invisible to human sight, are created in the cores of active galaxies, in cataclysmic stellar explosions, and in streams of gas expelled by the Sun and stars. The window on the heavens used by the X-ray astronomers shows the great drama of cosmic violence on the grandest scale. This account of X-ray astronomy incorporates the latest findings from several observatories operating in space. These include the Einstein Observatory operated by NASA, and the EXOSAT satellite of the European Space Agency. The book covers the entire field, with chapters on stars, supernova remnants, normal and active galaxies, clusters of galaxies, the diffuse X-ray background, and much more. The authors review basic principles, include the necessary historical background, and explain exactly what we know from X-ray observations of the Universe.

X-ray imaging system

International Nuclear Information System (INIS)

Houston, J.M.

1980-01-01

A novel, high-speed apparatus for use in X-ray computerised tomography is described in detail. It consists of a semi-circular array of X-ray sources, collimators and an ion chamber array for detection of the X-rays. The X-ray sources may be pulsed in salvos such that the corresponding detectors in the array are only illuminated by one source. The use of computer controlled salvos speeds up the image processing by at least a factor of two. The ion chamber array is designed to have a constant detection efficiency for varying angles of X-ray incidence. A detailed description of the detector construction and suggested gaseous fillings are given. It is claimed that the present tomographic system allows fast and accurate imaging of internal body organs and is insensitive to the blurring effects which motion of these organs tends to produce. (UK)

Ultra-short X-ray sources generated through laser-matter interaction and their applications; Sources de rayonnement X ultrabref generees par interaction laser-matiere et leurs applications

Energy Technology Data Exchange (ETDEWEB)

Rousse, A

2004-04-15

This work is dedicated to the sources of ultra-short X-rays. The K{sub {alpha}} source, the non-linear Thomson source, the betatron source and the X-{gamma} source are presented. We show that a pump-probe experiment where the pump is a laser excitation and the probe is the X-K{sub {alpha}} ultra-short radiation, can be used to study the dynamics of material structure with a time resolution of 100 femtosecond. We describe 2 applications that have been achieved in the field of solid physics by using the diffraction technique with a time resolution in the range of the femtosecond. The first application has permitted the observation and characterization of the ultra-quick solid-phase transition that occurs on the surface of a semiconductor crystal. The second experiment deals with the role of optical phonons in the antecedent processes that lead to such ultra-quick solid-phase transitions. (A.C.)

Femtosecond X-ray magnetic circular dichroism absorption spectroscopy at an X-ray free electron laser

Energy Technology Data Exchange (ETDEWEB)

Higley, Daniel J., E-mail: dhigley@stanford.edu; Yuan, Edwin [SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Department of Applied Physics, Stanford University, Stanford, California 94305 (United States); Hirsch, Konstantin; Dakovski, Georgi L.; Jal, Emmanuelle; Lutman, Alberto A.; Coslovich, Giacomo; Hart, Philip; Hoffmann, Matthias C.; Mitra, Ankush; Moeller, Stefan; Ohldag, Hendrik; Seaberg, Matthew; Stöhr, Joachim; Nuhn, Heinz-Dieter; Reid, Alex H.; Dürr, Hermann A.; Schlotter, William F. [SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Liu, Tianmin; MacArthur, James P. [SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Department of Physics, Stanford University, Stanford, California 94305 (United States); and others

2016-03-15

X-ray magnetic circular dichroism spectroscopy using an X-ray free electron laser is demonstrated with spectra over the Fe L{sub 3,2}-edges. The high brightness of the X-ray free electron laser combined with high accuracy detection of incident and transmitted X-rays enables ultrafast X-ray magnetic circular dichroism studies of unprecedented sensitivity. This new capability is applied to a study of all-optical magnetic switching dynamics of Fe and Gd magnetic sublattices in a GdFeCo thin film above its magnetization compensation temperature.

Distortion of absorption-line velocity curves due to x-ray heating in x-ray binaries

International Nuclear Information System (INIS)

Milgrom, M.

1976-01-01

The effects of X-ray heating on the measured absorption line velocities, in X-ray binaries with low X-rays to optical luminosities ratio are considered. These effects may be appreciable even for such binaries where the effect of X-ray heating on the light-curve is negligible. The effects are studied qualitatively and suggest possible ways to partially eliminate the systematic errors introduced by them. The individual systems Cyg x-1 and SMC x-1 are treated and the results of numerical calculations are presented for them. For Cyg x-1 it is found that the effect is detectable during the X-ray 'high' state in all regions of the spectrum. During the 'low' state it may be important in the red region of the spectrum. The results for the case in which soft X-ray fluxes (E < or approximately .4 keV, suggested by theoretical models) are present are also given. For SMC x-1 a strong effect for Hα, Hβ, Hγ had been found. This effect may be responsible for the observed variable velocity curve. We also find for SMC x-1 that the average X-ray intensity falling on the primary must be considerably smaller than what is derived from the detected flux, or else the effect is too large. (author)

X-ray generation by femtosecond laser pulses and its application to soft X-ray imaging microscope

International Nuclear Information System (INIS)

Ikeda, Kenichi; Kotaki, Hideyuki; Nakajima, Kazuhisa

2002-01-01

We have developed laser-produced plasma X-ray sources using femtosecond laser pulses at 10Hz repetition rate in a table-top size in order to investigate basic mechanism of X-ray emission from laser-matter interactions and its application to a X-ray microscope. In a soft X-ray region over 5 nm wavelength, laser-plasma X-ray emission from a solid target achieved an intense flux of photons of the order of 1011 photons/rad per pulse with duration of a few 100 ps, which is intense enough to make a clear imaging in a short time exposure. As an application of laser-produced plasma X-ray source, we have developed a soft X-ray imaging microscope operating in the wavelength range around 14 nm. The microscope consists of a cylindrically ellipsoidal condenser mirror and a Schwarzshird objective mirror with highly-reflective multilayers. We report preliminary results of performance tests of the soft X-ray imaging microscope with a compact laser-produced plasma X-ray source

Equipment for x- and gamma ray radiography

International Nuclear Information System (INIS)

Abd Nasir Ibrahim; Azali Muhammad; Ab Razak Hamzah; Abd Aziz Mohamed; Mohammad Pauzi Ismail

2004-01-01

The following topics related to the equipment for x - and gamma ray radiography are discussed in this chapter. The topics are x-ray source for Industrial Radiography: properties of x-ray, generation of x-ray, mechanism of x-ray production, x-ray equipment, power supply, distribution of x-ray intensity along the tube: gamma ray source for Industrial Radiography: properties of gamma rays, gamma ray sources, gamma ray projectors on cameras, source changing. Care of Radiographic Equipments: Merits and Demerits of x and Gamma Rays

Si(Li) X-ray detector

International Nuclear Information System (INIS)

Yuan Xianglin; Li Zhiyong; Hong Xiuse

1990-08-01

The fabrication technology of the 10∼80 mm 2 Si(Li) X-ray detectors are described and some problems concerning technology and measurement are discussed. The specifications of the detectors are shown as well. The Si(Li) X-ray detector is a kind of low energy X-ray detectors. Owing to very high energy resolution, fine linearity and high detection efficiency in the range of low energy X-rays, it is widely used in the fields of nuclear physics, medicine, geology and environmental protection, etc,. It is also a kernel component for the scanning electron microscope and X-ray fluorescence analysis systems

Guides for intraoral x-rays

International Nuclear Information System (INIS)

Ogunsunlade, O.A.

1988-01-01

An h-shaped exterior guide for use in combination with a SNAP-A-RAY film holder for accurately aligning a beam from an X-ray cone with an X-ray film during the process of taking intraoral periapical dental X-rays of the maxillary and mandibular teeth is described comprising: a first guide arm laterally and detachably connectable through a housing means; a traverse arm extending from the midpoint of the first guide arm and parallel to the X-ray film; and a second guide arm extending perpendicularly from an end of the traverse arm toward a plane of the X-ray film and in parallel relation up to an end point of the first guide arm

PAL-XFEL soft X-ray scientific instruments and X-ray optics: First commissioning results

Science.gov (United States)

Park, Sang Han; Kim, Minseok; Min, Changi-Ki; Eom, Intae; Nam, Inhyuk; Lee, Heung-Soo; Kang, Heung-Sik; Kim, Hyeong-Do; Jang, Ho Young; Kim, Seonghan; Hwang, Sun-min; Park, Gi-Soo; Park, Jaehun; Koo, Tae-Yeong; Kwon, Soonnam

2018-05-01

We report an overview of soft X-ray scientific instruments and X-ray optics at the free electron laser (FEL) of the Pohang Accelerator Laboratory, with selected first-commissioning results. The FEL exhibited a pulse energy of 200 μJ/pulse, a pulse width of power of 10 500 was achieved. The estimated total time resolution between optical laser and X-ray pulses was <270 fs. A resonant inelastic X-ray scattering spectrometer was set up; its commissioning results are also reported.

X-ray survey of the Pleiades: dependence of X-ray luminosity on stellar age

International Nuclear Information System (INIS)

Micela, G.; Sciortino, S.; Serio, S.; Vaiana, G.S.; Golub, L.; Harnden, F.R.; Rosner, R.

1984-01-01

The study of X-ray emission of stellar clusters, allows to decouple the influence of some individual stellar parameters, as initial conditions, composition and age, on the stellar X-ray function. The authors report preliminary results from an Einstein X-ray survey of the Pleiades. (Auth.)

X-ray detector

International Nuclear Information System (INIS)

Whetten, N.R.; Houston, J.M.

1977-01-01

An ionization chamber for use in determining the spatial distribution of x-ray photons in tomography systems comprises a plurality of substantially parallel, planar anodes separated by parallel, planar cathodes and enclosed in a gas of high atomic weight at a pressure from approximately 10 atmospheres to approximately 50 atmospheres. The cathode and anode structures comprise metals which are substantially opaque to x-ray radiation and thereby tend to reduce the resolution limiting effects of x-ray fluoresence in the gas. In another embodiment of the invention the anodes comprise parallel conductive bars disposed between two planar cathodes. Guard rings eliminate surface leakage currents between adjacent electrodes. 8 figures

Structure of the Circumnuclear Region of Seyfert 2 Galaxies Revealed by RXTE Hard X-Ray Observations of NGC 4945

Science.gov (United States)

Madejski, G.; Zycki, P.; Done, C.; Valinia, A.; Blanco, P.; Rothschild, R.; Turek, B.

2000-01-01

NGC 4945 is one of the brightest Se.yfert galaxies on the sky at 100 keV, but is completely absorbed below 10 keV, implying an optical depth of the absorber to electron scattering of a few; its absorption column is probably the largest which still allows a direct view of the nucleus at hard X-ray energies. Our observations of it with the Rossi X-ray Timing Explorer (RXTE) satellite confirm the large absorption, which for a simple phenomenological fit using an absorber with Solar abundances implies a column of 4.5(sup 0.4, sub -0.4) x 10(exp 24) /sq cm. Using a a more realistic scenario (requiring Monte Carlo modeling of the scattering), we infer the optical depth to Thomson scattering of approximately 2.4. If such a scattering medium were to subtend a large solid angle from the nucleus, it should smear out any intrinsic hard X-ray variability on time scales shorter than the light travel time through it. The rapid (with a time scale of approximately a day) hard X-ray variability of NGC 4945 we observed with the RXTE implies that the bulk of the extreme absorption in this object does not originate in a parsec-size, geometrically thick molecular torus. Limits on the amount of scattered flux require that the optically thick material on parsec scales must be rather geometrically thin, subtending a half-angle < 10 deg. This is only marginally consistent with the recent determinations of the obscuring column in hard X-rays, where only a quarter of Seyfert 2s have columns which are optically thick, and presents a problem in accounting for the Cosmic X-ray Background primarily with AGN possessing the geometry as that inferred by us. The small solid angle of the obscuring material, together with the black hole mass (of approximately 1.4 x 10(exp 6) solar mass) from megamaser measurements. allows a robust determination of the source luminosity, which in turn implies that the source radiates at approximately 10% of the Eddington limit.

Stabilized x-ray generator power supply

International Nuclear Information System (INIS)

Saha, Subimal; Purushotham, K.V.; Bose, S.K.

1986-01-01

X-ray diffraction and X-ray fluorescence analysis are very much adopted in laboratories to determine the type and structure of the constituent compounds in solid materials, chemical composition of materials, stress developed on metals etc. These experiments need X-ray beam of fixed intensity and wave length. This can only be achieved by X-ray generator having highly stabilized tube voltage and tube current. This paper describes how X-ray tube high voltage and electron beam current are stabilized. This paper also highlights generation of X-rays, diffractometry and X-ray fluorescence analysis and their wide applications. Principle of operation for stabilizing the X-ray tube voltage and current, different protection circuits adopted, special features of the mains H.V. transformer and H.T. tank are described in this report. (author)

Duodenal X-ray diagnostics

International Nuclear Information System (INIS)

Scheppach, W.

1982-01-01

The publication provides an overview of duodenal X-ray diagnostics with the aid of barium meals in 1362 patients. The introducing paragraphs deal with the topographic anatomy of the region and the methodics of X-ray investigation. The chapter entitled ''processes at the duodenum itself'' describes mainly ulcers, diverticula, congenital anomalies, tumors and inflammations. The neighbourhood processes comprise in the first place diseases having their origin at the pancreas and bile ducts. As a conclusion, endoscopic rectograde cholangio-pancreaticography and percutaneous transhepatic cholangiography are pointed out as advanced X-ray investigation methods. In the annex of X-ray images some of the described phenomena are shown in exemplary manner. (orig./MG) [de

Higher coherent x-ray laser

International Nuclear Information System (INIS)

Hasegawa, Noboru; Nagashima, Keisuke; Kawachi, Tetsuya

2001-01-01

X-ray lasers generated by an ultra short pulse laser have advantages such as monochromatic, short pulse duration, small beam divergence, high intensity, and coherence. Spatial coherence is most important for applications, we have investigated the transient collisional excitation (TCE) scheme x-ray laser lasing from Ne-like titanium (31.6 nm), Ne-like silver (13.9 nm) and tin (11.9 nm). However, the spatial coherence was not so good with this scheme. We have been studying to improve the spatial coherence of the x-ray laser and have proposed to use coherent seed light tuned to the x-ray laser wavelength generated from higher harmonics generation (HHG), which is introduced to the x-ray laser medium (Ne-like titanium, Ni-like silver plasmas). We present about the theoretical study of the coupling efficiency HHG light with x-ray laser medium. (author)

Center for X-Ray Optics, 1986

International Nuclear Information System (INIS)

1987-07-01

The Center for X-Ray Optics has made substantial progress during the past year on the development of very high resolution x-ray technologies, the generation of coherent radiation at x-ray wavelengths, and, based on these new developments, had embarked on several scientific investigations that would not otherwise have been possible. The investigations covered in this report are topics on x-ray sources, x-ray imaging and applications, soft x-ray spectroscopy, synchrotron radiation, advanced light source and magnet structures for undulators and wigglers

Rothmund-Thomson Syndrome: A 13-Year Follow-Up

Directory of Open Access Journals (Sweden)

Guillermo Antonio Guerrero-González

2014-07-01

Full Text Available Rothmund-Thomson syndrome (RTS is a rare autosomal recessive disorder presenting with poikiloderma and other clinical features, affecting the bones and eyes and, in type II RTS, presenting an increased risk for malignancy. With about 300 cases reported so far, we present a 13-year follow-up including clinical images, X-rays and genetic analysis. A 13-month-old female started with a facial rash with blisters on her cheeks and limbs at the age of 3 months along with congenital hypoplastic thumbs, frontal bossing and fine hair, eyebrows and eyelashes. The patient was lost to follow-up and returned 12 years later with palmoplantar hyperkeratotic lesions, short stature, disseminated poikiloderma and sparse scalp hair, with absence of eyelashes and eyebrows. Radiographic analysis showed radial ray defect, absence of the thumb and three wrist carpal bones, and reduced bone density. Gene sequencing for the RECQL4 helicase gene revealed a mutation on each allele. RTS is a rare disease, and in this patient we observed the evolution of her skin lesions and other clinical features, which were important for the classification of type II RTS. The next years will provide even more information on this rare disease.

Observing Solvation Dynamics with Simultaneous Femtosecond X-ray Emission Spectroscopy and X-ray Scattering

DEFF Research Database (Denmark)

Haldrup, Kristoffer; Gawelda, Wojciech; Abela, Rafael

2016-01-01

and structural changes, and local solvent structural changes are desired. We have studied the intra- and intermolecular dynamics of a model chromophore, aqueous [Fe(bpy)3]2+, with complementary X-ray tools in a single experiment exploiting intense XFEL radiation as a probe. We monitored the ultrafast structural...... rearrangement of the solute with X-ray emission spectroscopy, thus establishing time zero for the ensuing X-ray diffuse scattering analysis. The simultaneously recorded X-ray diffuse scattering atterns reveal slower subpicosecond dynamics triggered by the intramolecular structural dynamics of the photoexcited...

Equipment, components and production of x-ray

International Nuclear Information System (INIS)

Idris Besar

2004-01-01

The contents of this chapter are follows - Equipment, Components and Production of x-Ray: x-ray system, generator, control panel. x-ray tube, cathode, anode, envelope, housing, collimator, other components, x-ray production, Bremsstrahlung x-ray, characteristic x-ray, heat production

The X-ray Astronomy Recovery Mission

Science.gov (United States)

Tashiro, M.; Kelley, R.

2017-10-01

On 25 March 2016, the Japanese 6th X-ray astronomical satellite ASTRO-H (Hitomi), launched on February 17, lost communication after a series of mishap in its attitude control system. In response to the mishap the X-ray astronomy community and JAXA analyzed the direct and root cause of the mishap and investigated possibility of a recovery mission with the international collaborator NASA and ESA. Thanks to great effort of scientists, agencies, and governments, the X-ray Astronomy Recovery Mission (XARM) are proposed. The recovery mission is planned to resume high resolution X-ray spectroscopy with imaging realized by Hitomi under the international collaboration in the shortest time possible, simply by focusing one of the main science goals of Hitomi Resolving astrophysical problems by precise high-resolution X-ray spectroscopy'. XARM will carry a 6 x 6 pixelized X-ray micro-calorimeter on the focal plane of an X-ray mirror assembly, and an aligned X-ray CCD camera covering the same energy band and wider field of view, but no hard X-ray or soft gamma-ray instruments are onboard. In this paper, we introduce the science objectives, mission concept, and schedule of XARM.

Femtosecond X-ray Absorption Spectroscopy at a Hard X-ray Free Electron Laser

DEFF Research Database (Denmark)

Lemke, Henrik T.; Bressler, Christian; Chen, Lin X.

2013-01-01

X-ray free electron lasers (XFELs) deliver short (current (SASE based) XFELs, they can be used for measuring high......-quality X-ray absorption data and we report femtosecond time-resolved X-ray absorption near-edge spectroscopy (XANES) measurements of a spin-crossover system, iron(II) tris(2,2'-bipyridine) in water. The data indicate that the low-spin to high-spin transition can be modeled by single-exponential kinetics...

Small scale soft x-ray lasers

International Nuclear Information System (INIS)

Skinner, C.H.; DiCicco, D.S.; Kim, D.; Voorhees, D.; Suckewer, S.

1990-01-01

The widespread application of soft x-ray laser technology is contingent on the development of small scale soft x-ray lasers that do not require large laser facilities. Progress in the development of soft x-ray lasers pumped by a Nd laser of energy 6-12J is reported below. Application of an existing soft x-ray laser to x-ray microscopy has begun. A soft x-ray laser of output energy 1-3 mJ at 18,2 nm has been used to record high resolution images of biological specimens. The contact images were recorded on photoresist which was later viewed in a scanning electron microscope. The authors present a composite optical x-ray laser microscope design

Characterization of Metalloproteins and Biomaterials by X-ray Absorption Spectroscopy and X-ray Diffraction

DEFF Research Database (Denmark)

Frankær, Christian Grundahl

This thesis presents thework on combining complementary X-rays techniques for studying the structures of proteins and other biomaterials, and consists of three different projects: (i) Characterization of protein powders with X-ray powder diffraction (XRPD). (ii) The combination of X-ray...... crystallography and X-ray absorption spectroscopy (XAS) applied to studying different hexameric insulin conformations. (iii) The structures of polymorphs of strontium ranelate and the distribution of strontium in bone tissue. A procedure for fast identification and verification of protein powders using XRPD...... was correction for disordered bulk-solvent, but also correction for background and optimization of unit cell parameters have to be taken into account. A sample holder was designed for collecting powder diffraction data on a standard laboratory X-ray powder diffractometer. The background was reduced by use...

Cryotomography x-ray microscopy state

Science.gov (United States)

Le Gros, Mark; Larabell, Carolyn A.

2010-10-26

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

X-Ray Exam: Neck (For Parents)

Science.gov (United States)

... Staying Safe Videos for Educators Search English Español X-Ray Exam: Neck KidsHealth / For Parents / X-Ray Exam: ... Neck Enlarged Adenoids Croup Sinusitis Getting an X-ray (Video) X-Ray (Video) View more Partner Message About Us ...

X-ray astronomy

International Nuclear Information System (INIS)

Giacconi, R.; Setti, G.

1980-01-01

This book contains the lectures, and the most important seminars held at the NATO meeting on X-Ray astronomy in Erice, July 1979. The meeting was an opportune forum to discuss the results of the first 8-months of operation of the X-ray satellite, HEAO-2 (Einstein Observatory) which was launched at the end of 1978. Besides surveying these results, the meeting covered extragalactic astronomy, including the relevant observations obtained in other portions of the electromagnetic spectrum (ultra-violet, optical, infrared and radio). The discussion on galactic X-ray sources essentially covered classical binaries, globular clusters and bursters and its significance to extragalactic sources and to high energy astrophysics was borne in mind. (orig.)

Handbook of X-Ray Data

CERN Document Server

Zschornack, Günter

2007-01-01

This sourcebook is intended as an X-ray data reference for scientists and engineers working in the field of energy or wavelength dispersive X-ray spectrometry and related fields of basic and applied research, technology, or process and quality controlling. In a concise and informative manner, the most important data connected with the emission of characteristic X-ray lines are tabulated for all elements up to Z = 95 (Americium). This includes X-ray energies, emission rates and widths as well as level characteristics such as binding energies, fluorescence yields, level widths and absorption edges. The tabulated data are characterized and, in most cases, evaluated. Furthermore, all important processes and phenomena connected with the production, emission and detection of characteristic X-rays are discussed. This reference book addresses all researchers and practitioners working with X-ray radiation and fills a gap in the available literature.

THE THOMSON SURFACE. I. REALITY AND MYTH

International Nuclear Information System (INIS)

Howard, T. A.; DeForest, C. E.

2012-01-01

The solar corona and heliosphere are visible via sunlight that is Thomson-scattered off free electrons and detected by coronagraphs and heliospheric imagers. It is well known that these instruments are most responsive to material at the 'Thomson surface', the sphere with a diameter passing through both the observer and the Sun. It is less well known that in fact the Thomson scattering efficiency is minimized on the Thomson surface. Unpolarized heliospheric imagers such as STEREO/HI are thus approximately equally responsive to material over more than a 90° range of solar exit angles at each given position in the image plane. We call this range of angles the 'Thomson plateau'. We observe that heliospheric imagers are actually more sensitive to material far from the Thomson surface than close to it, at a fixed radius from the Sun. We review the theory of Thomson scattering as applied to heliospheric imaging, feature detection in the presence of background noise, geometry inference, and feature mass measurement. We show that feature detection is primarily limited by observing geometry and field of view, that the highest sensitivity for detection of density features is to objects close to the observer, that electron surface density inference is independent of geometry across the Thomson plateau, and that mass inference varies with observer distance in all geometries. We demonstrate the sensitivity results with a few examples of features detected by STEREO, far from the Thomson surface.

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 ...

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.

X-ray diagnostics - benefits and risks

International Nuclear Information System (INIS)

Bartholomaeus, Melanie

2016-01-01

The brochure on benefits and risks of X-ray diagnostics discusses the following issues: X radiation - a pioneering discovery and medical sensation, fundamentals of X radiation, frequency of X-ray examinations in Germany in relation to CT imaging, radiation doses resulting from X-ray diagnostics, benefits of X-ray diagnostics - indication and examples, risks - measures for radiation exposure reductions, avoidance of unnecessary examinations.

Flash x-ray cinematography

International Nuclear Information System (INIS)

Stein, W.E.

1976-01-01

Experiments intended to provide an overview of the potential capabilities and limitations of flash x-ray cinematography as a diagnostic technique for a Fast Reactor Safety Test Facility are described. The results provide estimates of the x-ray pulse intensity required to obtain adequate radiographs of an array of fuel pins in a typical reactor configuration. An estimate of the upper limit on the pulse duration imposed by the reactor background radiation was also determined. X-ray cinematography has been demonstrated at a repetition rate limited only by the recording equipment on hand at the time of these measurements. These preliminary results indicate that flash x-ray cinematography of the motion of fuel in a Fast Reactor Test Facility is technically feasible

Miniature x-ray source

Science.gov (United States)

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

2000-01-01

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

X-rays utilization

International Nuclear Information System (INIS)

Rebigan, F.

1979-03-01

The modality of X-ray utilization in different activities and economy is given. One presents firstly quantities and units used in radiation dosimetry and other fields. One gives the generation of X-rays, their properties as well as the elements of radiation protection. The utilization characteristics of these radiations in different fields are finally given. (author)

Flexible digital x-ray technology for far-forward remote diagnostic and conformal x-ray imaging applications

Science.gov (United States)

Smith, Joseph; Marrs, Michael; Strnad, Mark; Apte, Raj B.; Bert, Julie; Allee, David; Colaneri, Nicholas; Forsythe, Eric; Morton, David

2013-05-01

Today's flat panel digital x-ray image sensors, which have been in production since the mid-1990s, are produced exclusively on glass substrates. While acceptable for use in a hospital or doctor's office, conventional glass substrate digital x-ray sensors are too fragile for use outside these controlled environments without extensive reinforcement. Reinforcement, however, significantly increases weight, bulk, and cost, making them impractical for far-forward remote diagnostic applications, which demand rugged and lightweight x-ray detectors. Additionally, glass substrate x-ray detectors are inherently rigid. This limits their use in curved or bendable, conformal x-ray imaging applications such as the non-destructive testing (NDT) of oil pipelines. However, by extending low-temperature thin-film transistor (TFT) technology previously demonstrated on plastic substrate- based electrophoretic and organic light emitting diode (OLED) flexible displays, it is now possible to manufacture durable, lightweight, as well as flexible digital x-ray detectors. In this paper, we discuss the principal technical approaches used to apply flexible display technology to two new large-area flexible digital x-ray sensors for defense, security, and industrial applications and demonstrate their imaging capabilities. Our results include a 4.8″ diagonal, 353 x 463 resolution, flexible digital x-ray detector, fabricated on a 6″ polyethylene naphthalate (PEN) plastic substrate; and a larger, 7.9″ diagonal, 720 x 640 resolution, flexible digital x-ray detector also fabricated on PEN and manufactured on a gen 2 (370 x 470 mm) substrate.

Diffracted X-ray tracking: new system for single molecular detection with X-rays

CERN Document Server

Sasaki, Y C; Adachi, S; Suzuki, Y; Yagi, N

2001-01-01

We propose a new X-ray methodology for direct observations of the behaviors of single molecular units in real time and real space. This new system, which we call Diffracted X-ray Tracking (DXT), monitors the Brownian motions of a single molecular unit by observations of X-ray diffracted spots from a nanocrystal, tightly bound to the individual single molecular unit in bio-systems. DXT does not determine any translational movements, but only orientational movements.

Diffracted X-ray tracking: new system for single molecular detection with X-rays

International Nuclear Information System (INIS)

Sasaki, Y.C.; Okumura, Y.; Adachi, S.; Suzuki, Y.; Yagi, N.

2001-01-01

We propose a new X-ray methodology for direct observations of the behaviors of single molecular units in real time and real space. This new system, which we call Diffracted X-ray Tracking (DXT), monitors the Brownian motions of a single molecular unit by observations of X-ray diffracted spots from a nanocrystal, tightly bound to the individual single molecular unit in bio-systems. DXT does not determine any translational movements, but only orientational movements

Radionuclide X-ray fluorescence analysis

International Nuclear Information System (INIS)

Cechak, T.

1994-01-01

The author's achievements in the title field are summarized and discussed. The following topics are dealt with: (i) principles of radionuclide X-ray fluorescence analysis; (ii) mathematical methods in X-ray fluorescence analysis; (iii) Ross differential filters; (iv) application of radionuclide X-ray fluorescence analysis in the coal industry (with emphasis on the determination of the ash content, sulfur content, and arsenic content of coal); and (v) evaluation of the X-ray fluorescence analyzer from the radiological safety point of view. (P.A.)

X-ray diagnostic in gas discharge

International Nuclear Information System (INIS)

Chen Suhe; Wang Dalun; Cui Gaoxian; Wang Mei; Fu Yibei; Zhang Xinwei; Zhang Wushou

1995-01-01

X rays were observed when the anomalous phenomenon in the metal loaded with deuterium studied by the gas-discharge method. Therefore the X-ray energy spectra were measured by the absorption method, the specific X-ray approach and the NaI scintillation counter, while X-ray intensity was estimated by using 7 Li thermoluminescent foils. The X-ray average energy measured by the absorption method is 27.6 +- 2.1 keV, which is fitted within the error extent to 26.0 +-2.4 keV monoenergetic X rays measured by the NaI scintillation counter

Arrangement for X-ray shield

International Nuclear Information System (INIS)

1980-01-01

X-ray screen unit consisting of a light transmissive carrier onto which scintillation material is deposited, which is able to generate light under the influence of incident X-ray irradiation, characterised in that the X-ray screen comprises a number of sectors, wherein the surface with respect to the incident X-radiation is maintained at an acute angle. (G.C.)

Infrared, radio, and x-ray observations of Cygnus X-3

International Nuclear Information System (INIS)

Becklin, E.E.; Hawkins, F.J.; Mason, K.O.; Matthews, K.; Neugebauer, G.; Packman, D.; Sanford, P.W.; Schupler, B.; Stark, A.; Wynn-Williams, C.G.

1974-01-01

The x-ray source Cygnus X-3 has been interpreted as being a binary system on the basis of extensive x-ray observations of periodic variability. At radio wavelengths, the source displays erratic outbursts. Cyg x-3 has not been detected visually but at infrared wavelengths periodic variations in phase with the x-ray variations have been reported. Infrared, x-ray and radio observations of Cyg X-3 made during 1973 through 1973 October are presented. (U.S.)

Soft X-ray radiation damage in EM-CCDs used for Resonant Inelastic X-ray Scattering

Science.gov (United States)

Gopinath, D.; Soman, M.; Holland, A.; Keelan, J.; Hall, D.; Holland, K.; Colebrook, D.

2018-02-01

Advancement in synchrotron and free electron laser facilities means that X-ray beams with higher intensity than ever before are being created. The high brilliance of the X-ray beam, as well as the ability to use a range of X-ray energies, means that they can be used in a wide range of applications. One such application is Resonant Inelastic X-ray Scattering (RIXS). RIXS uses the intense and tuneable X-ray beams in order to investigate the electronic structure of materials. The photons are focused onto a sample material and the scattered X-ray beam is diffracted off a high resolution grating to disperse the X-ray energies onto a position sensitive detector. Whilst several factors affect the total system energy resolution, the performance of RIXS experiments can be limited by the spatial resolution of the detector used. Electron-Multiplying CCDs (EM-CCDs) at high gain in combination with centroiding of the photon charge cloud across several detector pixels can lead to sub-pixel spatial resolution of 2-3 μm. X-ray radiation can cause damage to CCDs through ionisation damage resulting in increases in dark current and/or a shift in flat band voltage. Understanding the effect of radiation damage on EM-CCDs is important in order to predict lifetime as well as the change in performance over time. Two CCD-97s were taken to PTB at BESSY II and irradiated with large doses of soft X-rays in order to probe the front and back surfaces of the device. The dark current was shown to decay over time with two different exponential components to it. This paper will discuss the use of EM-CCDs for readout of RIXS spectrometers, and limitations on spatial resolution, together with any limitations on instrument use which may arise from X-ray-induced radiation damage.

The universe in X-rays

CERN Document Server

Hasinger, Günther

2008-01-01

In the last 45 years, X-ray astronomy has become an integral part of modern astrophysics and cosmology. There is a wide range of astrophysical objects and phenomena, where X-rays provide crucial diagnostics. In particular they are well suited to study hot plasmas and matter under extreme physical conditions in compact objects. This book summarizes the present status of X-ray astronomy in terms of observational results and their astrophysical interpretation. It is written for students, astrophysicists as well a growing community of physicists interested in the field. An introduction including historical material is followed by chapters on X-ray astronomical instrumentation. The next two parts summarize in 17 chapters the present knowledge on various classes of X-ray sources in the galactic and extragalactic realm. While the X-ray astronomical highlights discussed in this book are mainly based on results from ROSAT, ASCA, RXTE, BeppoSAX, Chandra and XMM-Newton, a final chapter provides an outlook on observation...

X-ray clusters of galaxies

International Nuclear Information System (INIS)

McKee, J.D.

1980-01-01

This work is in three chapters, of which the first is an introduction to clusters of galaxies. The second chapter describes the HEAO A-2 Survey of Abell Clusters. The 225 clusters of galaxies listed in Abell's (1958) catalog which are of distance class four or less, were surveyed for 2 to 10 keV x-ray emission. Thirty-two identifications of x-ray sources with the clusters were made, fluxes and error boxes were determined for these sources; twelve of the identifications are new. The x-ray luminosity function has been derived and analytical fits have been made, the best fit is f(L) = 26.9 x 10 -8 exp( - L 44 /1.7) per Mpc per 10 44 erg s -1 per 2 to 10 keV band pass. The relationship between x-ray luminosity, Bautz-Morgan type, Rood-Sastry type, and richness has also been examined. The contribution of clusters to the x-ray background has been calculated from the luminosity function and has been found to be 3.5%, and with 90% certainty, less than 8% in the 2 to 10 keV band pass, assuming that clusters were not brighter in the past than they are at present. If they were bright enough in the past to account for the x-ray background, the evolution must have scaled more rapidly than (1 + z) 7 if clusters formed at z = 3, or (1 + z) 5 if clusters formed at z = 10. Chapter Three examines x-ray emission from poor clusters of galaxies. Burns and Owens' (1979) sample of 25 4C radio sources which coincide with Zwicky clusters of galaxies has been searched for x-ray emission in the HEAO A-2 data base. X-ray emission was detected from five sources at the 3sigma level, two exceeded 5 sigma. The search for x-ray emission was prompted by the knowledge of the existence of distorted radio sources in the clusters. The distortion implies the presence of a relatively dense intracluster medium which is expected to produce thermal bremsstrahlung x-ray emission

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 ...

X-ray speckle correlation interferometer

International Nuclear Information System (INIS)

Eisenhower, Rachel; Materlik, Gerhard

2000-01-01

Speckle Pattern Correlation Interferometry (SPCI) is a well-established technique in the visible-light regime for observing surface disturbances. Although not a direct imaging technique, SPCI gives full-field, high-resolution information about an object's motion. Since x-ray synchrotron radiation beamlines with high coherent flux have allowed the observation of x-ray speckle, x-ray SPCI could provide a means to measure strains and other quasi-static motions in disordered systems. This paper therefore examines the feasibility of an x-ray speckle correlation interferometer

RXTE detects X-ray bursts from Circinus X-1

NARCIS (Netherlands)

Linares, M.; Soleri, P.; Watts, A.; Altamirano, D.; Armas-Padilla, M.; Cavecchi, Y.; Degenaar, N.; Kalamkar, M.; Kaur, R.; van der Klis, M.; Patruno, A.; Wijnands, R.; Yang, Y.; Casella, P.; Rea, N.

After the recent report of X-ray re-brightening (ATel #2608), RXTE has observed the peculiar neutron star X-ray binary Cir X-1 eleven times during the last two weeks (May 11-25, 2010). We report the detection of nine X-ray bursts in RXTE-PCA data, 25 years after the first -and the only previous-

Handbook Of X-ray Astronomy

Science.gov (United States)

Arnaud, Keith A.; Smith, R. K.; Siemiginowska, A.; Edgar, R. J.; Grant, C. E.; Kuntz, K. D.; Schwartz, D. A.

2011-09-01

This poster advertises a book to be published in September 2011 by Cambridge University Press. Written for graduate students, professional astronomers and researchers who want to start working in this field, this book is a practical guide to x-ray astronomy. The handbook begins with x-ray optics, basic detector physics and CCDs, before focussing on data analysis. It introduces the reduction and calibration of x-ray data, scientific analysis, archives, statistical issues and the particular problems of highly extended sources. The book describes the main hardware used in x-ray astronomy, emphasizing the implications for data analysis. The concepts behind common x-ray astronomy data analysis software are explained. The appendices present reference material often required during data analysis.

Total-reflection x-ray fluorescence with a brillant undulator x-ray source

International Nuclear Information System (INIS)

Sakurai, K.; Eba, H.; Numako, C.; Suzuki, M.; Inoue, K.; Yagi, N.

2000-01-01

Total-reflection x-ray fluorescence (TXRF) is a highly sensitive technique for analyzing trace elements, because of the very low background from the sample support. Use of third-generation synchrotron x-ray source could further enhance the detection power. However, while such high sensitivity permits the detection of signals from trace elements of interest, it also means that one can observe weak parasitic x-rays as well. If the sample surface becomes even slightly contaminated, owing to air particulates near the beamline, x-ray fluorescence lines of iron, zinc, copper, nickel, chromium, and titanium can be observed even for a blank sample. Another critical problem is the low-energy-side tail of the scattering x-rays, which ultimately restricts the detection capability of the technique using a TXRF spectrometer based on a Si(Li) detector. The present paper describes our experiments with brilliant undulator x-ray beams at BL39XU and BL40XU, at the SPring-8, Harima, Japan. The emphasis is on the development of instruments to analyze a droplet of 0.1 μl containing trace elements of ppb level. Although the beamline is not a clean room, we have employed equipment for preparing a clean sample and also for avoiding contamination during transferring the sample into the spectrometer. We will report on the successful detection of the peak from 0.8 ppb selenium in a droplet (absolute amount 80 fg). We will also present the results of recent experiments obtained from a Johansson spectrometer rather than a Si(Li) detector. (author)

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)

A low power x-ray tube for use in energy dispersive x-ray fluorescence analysis

International Nuclear Information System (INIS)

Kataria, S.K.; Govil, Rekha; Lal, M.

1980-01-01

A low power X-ray tube with thin molybdenum transmission target for use in energy dispersive X-ray fluorescence (ENDXRF) element analysis has been indigenously built, along with its power supply. The X-ray tube has been in operation since August 1979, and it has been operated upto maximum target voltage of 35 KV and tube current upto 200 μA which is more than sufficient for trace element analysis. This X-ray tube has been used alongwith the indigenously built Si(Li) detector X-ray spectrometer with an energy resolution of 200 eV at 5.9 Kev MnKsub(α) X-ray peak for ENDXRF analysis. A simple procedure of calibration has been developed for thin samples based on the cellulose diluted, thin multielement standard pellets. Analytical sensitivities of the order of a few p.p.m. have been obtained with the experimental setup for elements with 20 < = Z < = 38 and 60 < = Z < = 90. A number of X-ray spectra for samples of environmental, biological, agricultural, industrial and metallurgical interest are presented to demonstrate the salient features of the experimental sep up. (auth.)

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

NARCIS (Netherlands)

Schioppa, E.J.

2014-01-01

Energy sensitive X-ray imaging detectors are produced by connecting a semiconductor sensor to a spectroscopic pixel readout chip. In this thesis, the applicability of such detectors to X-ray Computed Tomography (CT) is studied. A prototype Medipix based silicon detector is calibrated using X-ray

Synchronization of x-ray pulses to the pump laser in an ultrafast x-ray facility

International Nuclear Information System (INIS)

Corlett, J.N.; Barry, W.; Byrd, J.M.; Schoenlein, R.; Zholents, A.

2002-01-01

Accurate timing of ultrafast x-ray probe pulses emitted from a synchrotron radiation source with respect to a pump laser exciting processes in the sample under study is critical for the investigation of structural dynamics in the femtosecond regime. We describe a scheme for synchronizing femtosecond x-ray pulses relative to a pump laser. X-ray pulses of <100 fs duration are generated from a proposed source based on a recirculating superconducting linac [1,2,3]. Short x-ray pulses are obtained by a process of electron pulse compression, followed by transverse temporal correlation of the electrons, and ultimately x-ray pulse compression. Timing of the arrival of the x-ray pulse with respect to the pump laser is found to be dominated by the operation of the deflecting cavities which provide the transverse temporal correlation of the electrons. The deflecting cavities are driven from a highly stable RF signal derived from a modelocked laser oscillator which is also the origin of the pump l aser pulses

X-ray microscopy in Aarhus

International Nuclear Information System (INIS)

Uggerhoej, Erik; Abraham-Peskir, Joanna V.

2000-01-01

The Aarhus imaging soft X-ray microscope is now a busy multi-user facility. The optical set-up will be described and project highlights discussed. a) Metal-induced structural changes in whole cells in solution. The effects of aluminum, copper, nickel and zinc on protozoa investigated by using a combination of light microscopy, confocal scanning laser microscopy and X-ray microscopy. b) Botanical studies by X-ray microscopy used to compliment electron microscopy studies. c) Sludge morphology and iron precipitation in Danish freshwater plants by combining X-ray, scanning electron and transmission electron microscopy

X-ray fluorescence in geology

International Nuclear Information System (INIS)

Dutra, C.V.; Gomes, C.B.

1990-01-01

This work is about the X-ray fluorescence aplication in geology. It's showing the X-ray origin and excitation. About the instrumentation this work shows the following: X-ray tubes, colimators, analysers crystals, detectors, amplifiers, pulse height selector, and others electronic components. By X-ray fluorescente are done quantitative and qualitative geological analysis and this work shows this analysis and its detection limits. The problems determination is the example. In this work was done yet the comparative analysis of the various instrumental methods in geochemistry. (C.G.) [pt

Medical x-ray

International Nuclear Information System (INIS)

Abd Aziz Mhd Ramli; Gui Ah Auu; Husaini Salleh; Idris Besar; Mohd Ashhar Khalid; Muhammad Jamal Md Isa; Shaharuddin Mohd; Siti Najila Mohd Janib; Mohamed Ali Abdul Khader; Mahalatchimi Dave; Mohd Fazly Abdul Rahim; Ng Chee Moon; Ram Piari; Teoh Hoon Heng; Lee Peter

2004-01-01

This book describes the fundamental subject about medical radiography. It is a multidisciplinary field that requires cross professional input from scientists, engineers and medical doctors. However, it is presented in simple language to suit different levels of readers from x-ray operators and radiographers to physists, general practitioners and radiology specialists.The book is written in accordance to the requirements of the standard syllabus approved by the Ministry of Health Malaysia for the training of medical x-ray operator and general practitioners. In general, the content is not only designed to provide relevant and essential subject for related professionals in medical radiological services such as x-ray operator, radiographer and radiologists, but also to address those in associated radiological services including nurses, medical technologists and physicists.The book is organized and arranged sequentially into 3 parts for easy reference: Radiation safety; X-ray equipment and associated facilities; Radiography practices. With proper grasping of all these parts, the radiological services could be provided with confident and the highest professional standard. Thus, medical imaging with highest quality that can provide useful diagnostic information at minimum doses and at cost effective could be assured

X-ray Emission from Solar Flares

Indian Academy of Sciences (India)

2016-01-27

Jan 27, 2016 ... Solar flares; X-ray detectors; X-ray line emission and continuum; break energy; microflares. Abstract. Solar X-ray Spectrometer (SOXS), the first space-borne solar astronomy experiment of India was designed to improve our current understanding of X-ray emission from the Sun in general and solar flares in ...

Bone X-Ray (Radiography)

Medline Plus

Full Text Available ... can be taken to the patient in a hospital bed or the emergency room. The x-ray ... position possible that still ensures x-ray image quality. top of page Who interprets the results and ...

Bone X-Ray (Radiography)

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Full Text Available ... current x-ray images for diagnosis and disease management. top of page How is the procedure performed? ... position possible that still ensures x-ray image quality. top of page Who interprets the results and ...

Bone X-Ray (Radiography)

Medline Plus

Full Text Available ... the body. X-rays are the oldest and most frequently used form of medical imaging. A bone ... bones. top of page How should I prepare? Most bone x-rays require no special preparation. You ...

Bone X-Ray (Radiography)

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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 ...

Bone X-Ray (Radiography)

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Full Text Available ... tissue shows up in shades of gray and air appears black. Until recently, x-ray images were ... position possible that still ensures x-ray image quality. top of page Who interprets the results and ...

Bone X-Ray (Radiography)

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Full Text Available ... up in shades of gray and air appears black. Until recently, x-ray images were maintained on ... Safety page for more information about radiation dose. Women should always inform their physician or x-ray ...

Bone X-Ray (Radiography)

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Full Text Available ... wrist, arm, elbow, shoulder, spine, pelvis, hip, thigh, knee, leg (shin), ankle or foot. top of page ... the patient standing upright, as in cases of knee x-rays. A portable x-ray machine is ...

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 ...

Bone X-Ray (Radiography)

Medline Plus

Full Text Available ... conditions. Imaging with x-rays involves exposing a part of the body to a small dose of ... body. Once it is carefully aimed at the part of the body being examined, an x-ray ...

Low energy (soft) x rays

International Nuclear Information System (INIS)

Hoshi, Masaharu; Antoku, Shigetoshi; Russell, W.J.; Miller, R.C.; Nakamura, Nori; Mizuno, Masayoshi; Nishio, Shoji.

1987-05-01

Dosimetry of low-energy (soft) X rays produced by the SOFTEX Model CMBW-2 was performed using Nuclear Associates Type 30 - 330 PTW, Exradin Type A2, and Shonka-Wyckoff ionization chambers with a Keithley Model 602 electrometer. Thermoluminescent (BeO chip) dosimeters were used with a Harshaw Detector 2000-A and Picoammeter-B readout system. Beam quality measurements were made using aluminum absorbers; exposure rates were assessed by the current of the X-ray tube and by exposure times. Dose distributions were established, and the average factors for non-uniformity were calculated. The means of obtaining accurate absorbed and exposed doses using these methods are discussed. Survival of V79 cells was assessed by irradiating them with soft X rays, 200 kVp X rays, and 60 Co gamma rays. The relative biological effectiveness (RBE) values for soft X rays with 0, 0.2, 0.7 mm added thicknesses of aluminum were 1.6, which were compared to 60 Co. The RBE of 200 kVp X rays relative to 60 Co was 1.3. Results of this study are available for reference in future RERF studies of cell survival. (author)

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

Energy Technology Data Exchange (ETDEWEB)

Eckert, S., E-mail: sebastian.eckert@helmholtz-berlin.de, E-mail: martin.beye@helmholtz-berlin.de; Beye, M., E-mail: sebastian.eckert@helmholtz-berlin.de, E-mail: martin.beye@helmholtz-berlin.de; Pietzsch, A.; Quevedo, W.; Hantschmann, M. [Institute for Methods and Instrumentation in Synchrotron Radiation Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Str. 15, 12489 Berlin (Germany); Ochmann, M.; Huse, N. [Institute for Nanostructure and Solid State Physics, University of Hamburg, Jungiusstr. 11, 20355 Hamburg, Germany and Max Planck Institute for the Structure and Dynamics of Matter, Center for Free-Electron Laser Science, Luruper Chaussee 149, 22761 Hamburg (Germany); Ross, M.; Khalil, M. [Department of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195 (United States); Minitti, M. P.; Turner, J. J.; Moeller, S. P.; Schlotter, W. F.; Dakovski, G. L. [LCLS, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Föhlisch, A. [Institute for Methods and Instrumentation in Synchrotron Radiation Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Str. 15, 12489 Berlin (Germany); Institut für Physik und Astronomie, Universität Potsdam, Karl-Liebknecht-Str. 24/25, 14476 Potsdam (Germany)

2015-02-09

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

X-ray facility for the ground calibration of the X-ray monitor JEM-X on board INTEGRAL

DEFF Research Database (Denmark)

Loffredo, G.; Pelliciari, C.; Frontera, F.

2003-01-01

We describe the X-ray facility developed for the calibration of the X-ray monitor JEM-X on board the INTEGRAL satellite. The apparatus allowed the scanning of the detector geometric area with a pencil beam of desired energy over the major part of the passband of the instrument. The monochromatic...

X-ray screening materials

International Nuclear Information System (INIS)

Wardley, R.B.

1981-01-01

This invention relates to x-ray screening materials and especially to materials in sheet form for use in the production of, for example, protective clothing such as aprons and lower back shields, curtains, mobile screens and suspended shields. The invention is based on the observation that x-ray screening materials in sheet form having greater flexiblity than the hitherto known x-ray screening materials of the same x-ray absorber content can be produced if, instead of using a single sheet of filled sheet material of increased thickness, one uses a plurality of sheets of lesser thickness together forming a laminar material of the desired thickness and one bonds the individual sheets together at their edges and, optionally, at other spaced apart points away from the edges thereby allowing one sheet to move relative to another. (U.K.)

Magnetic x-ray microdiffraction

Energy Technology Data Exchange (ETDEWEB)

Evans, Paul G [Computer-Aided Engineering Center, University of Wisconsin, Madison, WI 53706 (United States); Isaacs, Eric D [Center for Nanoscale Materials, Argonne National Laboratory, Argonne, IL 60439 (United States)

2006-08-07

Magnetic x-ray microdiffraction uses the structural specificity of x-ray diffraction to probe complex magnetic structures at the length scales relevant to physical phenomena including domain dynamics and phase transitions. Conventional magnetic crystallography techniques such as neutron or x-ray diffraction lack this spatial resolution. The combination of both reciprocal space and real space resolution with a rich magnetic cross section allows new microscopy techniques to be developed and applied to magnetism at the scale of single domains. Potential applications include a wide range of magnetic problems in nanomagnetism, the interaction of strain, polarization and magnetization in complex oxides and spatially resolved studies of magnetic phase transitions. We present the physical basis for x-ray microdiffraction and magnetic scattering processes, review microdiffraction domain imaging techniques in antiferromagnetic and ferromagnetic materials and discuss potential directions for studies. (topical review)

Relation between X-Ray and γ-Ray Emissions for Fermi Blazars ...

Indian Academy of Sciences (India)

Abstract. Using γ-ray band data detected by Fermi Large Area Tele- scope (LAT) and X-ray band data for 78 blazars, we find a medium cor- relation between X-ray and γ-ray fluxes in the average state. A medium anticorrelation is also found between X-ray (1 KeV) mean spectral index αx and γ-ray mean spectral index αγ for ...

The Imaging X-ray Polarimetry Explorer (IXPE

Directory of Open Access Journals (Sweden)

Martin C. Weisskopf

Full Text Available The Imaging X-ray Polarimetry Explorer (IXPE expands observation space by simultaneously adding polarization to the array of X-ray source properties currently measured (energy, time, and location. IXPE will thus open new dimensions for understanding how X-ray emission is produced in astrophysical objects, especially in systems under extreme physical conditions. Keywords: X-ray astronomy, X-ray polarimetry, X-ray imaging

Radiation safety in X-ray facilities

International Nuclear Information System (INIS)

2001-09-01

The guide specifies the radiation safety requirements for structural shielding and other safety arrangements used in X-ray facilities in medical and veterinary X-ray activities and in industry, research and education. The guide is also applicable to premises in which X-ray equipment intended for radiation therapy and operating at a voltage of less than 25 kV is used. The guide applies to new X-ray facilities in which X-ray equipment that has been used elsewhere is transferred. The radiation safety requirements for radiation therapy X-ray devices operating at a voltage exceeding 25 kV, and for the premices in which such devices are used, are set out in Guide ST 2.2

Radiation safety in X-ray facilities

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-09-01

The guide specifies the radiation safety requirements for structural shielding and other safety arrangements used in X-ray facilities in medical and veterinary X-ray activities and in industry, research and education. The guide is also applicable to premises in which X-ray equipment intended for radiation therapy and operating at a voltage of less than 25 kV is used. The guide applies to new X-ray facilities in which X-ray equipment that has been used elsewhere is transferred. The radiation safety requirements for radiation therapy X-ray devices operating at a voltage exceeding 25 kV, and for the premices in which such devices are used, are set out in Guide ST 2.2.

Sensors for x-ray astronomy satellite

International Nuclear Information System (INIS)

Makino, Fumiyoshi; Kondo, Ichiro; Nishioka, Yonero; Kameda, Yoshihiko; Kubo, Masaki.

1980-01-01

For the purpose of observing the cosmic X-ray, the cosmic X-ray astronomy satellite (CORSA-b, named ''Hakucho'', Japanese for cygnus,) was launched Feb. 21, 1979 by Institute of Space and Aeronautical Science, University of Tokyo. The primary objectives of the satellite are: to perform panoramic survey of the space for X-ray bursts and to perform the spectral and temporal measurement of X-ray sources. The very soft X-ray sensor for X-ray observation and the horizon sensor for spacecraft attitude sensing were developed by Toshiba Corporation under technical support by University of Tokyo and Nagoya University for ''Hakucho''. The features of these sensors are outlined in this paper. (author)

X-ray and gamma radiography devices

International Nuclear Information System (INIS)

Abdul Nassir Ibrahim; Azali Muhammad; Ab. Razak Hamzah; Abd. Aziz Mohamed; Mohamad Pauzi Ismail

2008-01-01

When we are using this technique, we also must familiar with the device and instrument that used such as gamma projector, crawler, x-ray tubes and others. So this chapter discussed detailed on device used for radiography work. For the x-ray and gamma, their characteristics are same but the source to produce is a big different. X-ray produced from the machine meanwhile, gamma produce from the source such as Co-60 and IR-192. Both are electromagnetic waves. So, the reader can have some knowledge on what is x-ray tube, discrete x-ray and characteristic x-ray, how the machine works and how to control a machine, what is source for gamma emitter, how to handle the projector and lastly difference between x-ray and gamma. Of course this cannot be with the theory only, so detailed must be learned practically.

Transient soft X-ray sources

International Nuclear Information System (INIS)

Hayakawa, S.; Murakami, T.; Nagase, F.; Tanaka, Y.; Yamashita, K.

1976-01-01

A rocket observation of cosmic soft X-rays suggests the existence of transient, recurrent soft X-ray sources which are found variable during the flight time of the rocket. Some of the soft X-ray sources thus far reported are considered to be of this time. These sources are listed and their positions are shown. (Auth.)

Parabolic refractive X-ray lenses: a breakthrough in X-ray optics

CERN Document Server

Lengeler, B; Benner, B; Guenzler, T F; Kuhlmann, M; Tümmler, J; Simionovici, A S; Drakopoulos, M; Snigirev, A; Snigireva, I

2001-01-01

Refractive X-ray lenses, considered for a long time as unfeasible, have been realized with a rotational parabolic profile at our institute: The main features of the new lenses are: they focus in two directions and are free of spherical aberration. By varying the number of individual lenses in the stack the focal length can be chosen in a typical range from 0.5 to 2 m for photon energies between about 6 and 60 keV. The aperture of the lens is about 1 mm matching the angular divergence of undulator beams at 3d generation synchrotron radiation sources. They cope without problems with the heat load from the white beam of an undulator. Finally, they are easy to align and to operate. Refractive X-ray lenses can be used with hard X-rays in the same way as glass lenses can be used for visible light, if it is take into account that the numerical aperture is small (of the order 10 sup - sup 4). Being high-quality optical elements, the refractive X-ray lenses can be used for generating a focal spot in the mu m range wit...

Quasimonochromatic x-ray computed tomography by the balanced filter method using a conventional x-ray source

International Nuclear Information System (INIS)

Saito, Masatoshi

2004-01-01

A quasimonochromatic x-ray computed tomography (CT) system utilizing balanced filters has recently been developed for acquiring quantitative CT images. This system consisted of basic components such as a conventional x-ray generator for radiography, a stage for mounting and rotating objects, and an x-ray line sensor camera. Metallic sheets of Er and Yb were used as the balanced filters for obtaining quasimonochromatic incident x rays that include the characteristic lines of the W Kα doublet from a tungsten target. The mean energy and energy width of the quasimonochromatic x rays were determined to be 59.0 and 1.9 keV, respectively, from x-ray spectroscopic measurements using a high-purity Ge detector. The usefulness of the present x-ray CT system was demonstrated by obtaining spatial distributions of the linear attenuation coefficients of three selected samples--a 20 cm diameter cylindrical water phantom, a 3.5 cm diameter aluminum rod, and a human head phantom. The results clearly indicate that this apparatus is surprisingly effective for estimating the distribution of the linear attenuation coefficients without any correction of the beam-hardening effect. Thus, implementing the balanced filter method on an x-ray CT scanner has promise in producing highly quantitative CT images

X-Ray Exam: Femur (Upper Leg)

Science.gov (United States)

... Staying Safe Videos for Educators Search English Español X-Ray Exam: Femur (Upper Leg) KidsHealth / For Parents / X- ... Muscles, and Joints Broken Bones Getting an X-ray (Video) X-Ray (Video) View more Partner Message About Us ...

Bone X-Ray (Radiography)

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Full Text Available ... over time. top of page What are the benefits vs. risks? Benefits Bone x-rays are the fastest and easiest ... bear denotes child-specific content. Related Articles and Media Radiation Dose in X-Ray and CT Exams ...

Bone X-Ray (Radiography)

Medline Plus

Full Text Available ... clothing that might interfere with the x-ray images. Women should always inform their physician and x-ray ... lowest radiation dose possible while producing the best images for ... organizations continually review and update the technique standards used ...

Einstein pictures the x-ray sky

International Nuclear Information System (INIS)

Hartline, B.K.

1979-01-01

The second High Energy Astronomy Observatory (HEAO-2, Einstein) is revolutionizing x-ray astronomy just as its namesake revolutionized physics. Earlier x-ray observatories, including HEAO-1, were designed to scan the sky for x-ray emitters. With Einstein, the challenge has shifted from discovering x-ray sources to understanding the processes producing the x-rays. But having 500 times the sensitivity of previous detectors, Einstein makes more than its share of discoveries, too. For example, it sees distant quasars and clusters of galaxies that can barely be detected by the largest optical telescopes

NIKOLA TESLA AND THE X-RAY

OpenAIRE

Rade R. Babic

2005-01-01

After professor Wilhelm Konrad Röntgen published his study of an x-ray discovery (Academy Bulletin, Berlin, 08. 11. 1895.), Nikola Tesla published his first study of an x-ray on the 11th of March in 1896. (X-ray, Electrical Review). Until the 11th of August in 1897 he had published ten studies on this subject. All Tesla,s x-ray studies were experimental, which is specific to his work. Studying the nature of the x-ray, he established a new medical branch-radiology. He wrote:” There’s no doubt...

Polarized X-ray excitation for scatter reduction in X-ray fluorescence computed tomography.

Science.gov (United States)

Vernekohl, Don; Tzoumas, Stratis; Zhao, Wei; Xing, Lei

2018-05-25

X-ray fluorescence computer tomography (XFCT) is a new molecular imaging modality which uses X-ray excitation to stimulate the emission of fluorescent photons in high atomic number contrast agents. Scatter contamination is one of the main challenges in XFCT imaging which limits the molecular sensitivity. When polarized X-rays are used, it is possible to reduce the scatter contamination significantly by placing detectors perpendicular to the polarization direction. This study quantifies scatter contamination for polarized and unpolarized X-ray excitation and determines the advantages of scatter reduction. The amount of scatter in preclinical XFCT is quantified in Monte Carlo simulations. The fluorescent X-rays are emitted isotropically, while scattered X-rays propagate in polarization direction. The magnitude of scatter contamination is studied in XFCT simulations of a mouse phantom. In this study, the contrast agent gold is examined as an example but a scatter reduction from polarized excitation is also expected for other elements. The scatter reduction capability is examined for different polarization intensities with a monoenergetic X-ray excitation energy of 82 keV. The study evaluates two different geometrical shapes of CZT detectors which are modeled with an energy resolution of 1 keV FWHM at an X-ray energy of 80 keV. Benefits of a detector placement perpendicular to the polarization direction are shown in iterative and analytic image reconstruction including scatter correction. The contrast to noise ratio (CNR) and the normalized mean square error (NMSE) are analyzed and compared for the reconstructed images. A substantial scatter reduction for common detector sizes was achieved for 100% and 80% linear polarization while lower polarization intensities provide a decreased scatter reduction. By placing the detector perpendicular to the polarization direction, a scatter reduction by factor up to 5.5 can be achieved for common detector sizes. The image

Development of Compton X-ray spectrometer for high energy resolution single-shot high-flux hard X-ray spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Kojima, Sadaoki, E-mail: kojima-s@ile.osaka-u.ac.jp, E-mail: sfujioka@ile.osaka-u.ac.jp; Ikenouchi, Takahito; Arikawa, Yasunobu; Sakata, Shohei; Zhang, Zhe; Abe, Yuki; Nakai, Mitsuo; Nishimura, Hiroaki; Shiraga, Hiroyuki; Fujioka, Shinsuke, E-mail: kojima-s@ile.osaka-u.ac.jp, E-mail: sfujioka@ile.osaka-u.ac.jp; Azechi, Hiroshi [Institute of Laser Engineering, Osaka University, 2-6 Yamada-oka, Suita, Osaka 565-0871 (Japan); Ozaki, Tetsuo [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Miyamoto, Shuji; Yamaguchi, Masashi; Takemoto, Akinori [Laboratory of Advanced Science and Technology for Industry, University of Hyogo, 3-1-2 Kouto, Kamigori-cho, Ako-gun, Hyogo 678-1205 (Japan)

2016-04-15

Hard X-ray spectroscopy is an essential diagnostics used to understand physical processes that take place in high energy density plasmas produced by intense laser-plasma interactions. A bundle of hard X-ray detectors, of which the responses have different energy thresholds, is used as a conventional single-shot spectrometer for high-flux (>10{sup 13} photons/shot) hard X-rays. However, high energy resolution (Δhv/hv < 0.1) is not achievable with a differential energy threshold (DET) X-ray spectrometer because its energy resolution is limited by energy differences between the response thresholds. Experimental demonstration of a Compton X-ray spectrometer has already been performed for obtaining higher energy resolution than that of DET spectrometers. In this paper, we describe design details of the Compton X-ray spectrometer, especially dependence of energy resolution and absolute response on photon-electron converter design and its background reduction scheme, and also its application to the laser-plasma interaction experiment. The developed spectrometer was used for spectroscopy of bremsstrahlung X-rays generated by intense laser-plasma interactions using a 200 μm thickness SiO{sub 2} converter. The X-ray spectrum obtained with the Compton X-ray spectrometer is consistent with that obtained with a DET X-ray spectrometer, furthermore higher certainly of a spectral intensity is obtained with the Compton X-ray spectrometer than that with the DET X-ray spectrometer in the photon energy range above 5 MeV.

A library for X-ray-matter interaction cross sections for X-ray fluorescence applications

Energy Technology Data Exchange (ETDEWEB)

Brunetti, A. [Istituto di Matematica e Fisica, Universita di Sassari, via Vienna 2, 07100 Sassari (Italy) and INFN, Sezione di Cagliari (Italy)]. E-mail: brunetti@uniss.it; Sanchez del Rio, M. [European Synchrotron Radiation Facility, 6 rue Jules Horowitz, 38043 Grenoble Cedex (France); Golosio, B. [INFN, Sezione di Cagliari (Italy); European Synchrotron Radiation Facility, 6 rue Jules Horowitz, 38043 Grenoble Cedex (France); Simionovici, A. [European Synchrotron Radiation Facility, 6 rue Jules Horowitz, 38043 Grenoble Cedex (France); Laboratoire de Sciences de la Terre, Ecole Normale Superieure, Lyon, F-69364 (France); Somogyi, A. [European Synchrotron Radiation Facility, 6 rue Jules Horowitz, 38043 Grenoble Cedex (France)

2004-10-08

Quantitative estimate of elemental composition by spectroscopic and imaging techniques using X-ray fluorescence requires the availability of accurate data of X-ray interaction with matter. Although a wide number of computer codes and data sets are reported in literature, none of them is presented in the form of freely available library functions which can be easily included in software applications for X-ray fluorescence. This work presents a compilation of data sets from different published works and an xraylib interface in the form of callable functions. Although the target applications are on X-ray fluorescence, cross sections of interactions like photoionization, coherent scattering and Compton scattering, as well as form factors and anomalous scattering functions, are also available.

X-ray interferometric Fourier holography

International Nuclear Information System (INIS)

Balyan, M.K.

2016-01-01

The X-ray interferometric Fourier holography is proposed and theoretically investigated. Fourier The X-ray interferometric Young fringes and object image reconstruction are investigated. It is shown that the interference pattern of two slits formed on the exit surface of the crystal-analyzer (the third plate of the interferometer) is the X-ray interferometric Young fringes. An expression for X-ray interferometric Young fringes period is obtained. The subsequent reconstruction of the slit image as an object is performed by means of Fourier transform of the intensity distribution on the hologram. Three methods of reconstruction of the amplitude transmission complex function of the object are presented: analytical - approximate method, method of iteration and step by step method. As an example the X-ray Fourier interferometric hologram recording and the complex amplitude transmission function reconstruction for a beryllium circular wire are considered

Handbook of X-Ray Astronomy

Science.gov (United States)

Arnaud, Keith A. (Editor); Smith, Randall K.; Siemiginowska, Aneta

2011-01-01

X-ray astronomy was born in the aftermath of World War II as military rockets were repurposed to lift radiation detectors above the atmosphere for a few minutes at a time. These early flights detected and studied X-ray emission from the Solar corona. The first sources beyond the Solar System were detected during a rocket flight in 1962 by a team headed by Riccardo Giaccom at American Science and Engineering, a company founded by physicists from MIT. The rocket used Geiger counters with a system designed to reduce non-X-ray backgrounds and collimators limiting the region of sky seen by the counters. As the rocket spun, the field of view (FOV) happened to pass over what was later found to be the brightest non-Solar X-ray source; later designated See X-1. It also detected a uniform background glow which could not be resolved into individual sources. A follow-up campaign using X-ray detectors with better spatial resolution and optical telescopes identified See X-1 as an interacting binary with a compact (neutron star) primary. This success led to further suborbital rocket flights by a number of groups. More X-ray binaries were discovered, as well as X-ray emission from supernova remnants, the radio galaxies M87 and Cygnus-A, and the Coma cluster. Detectors were improved and Geiger counters were replaced by proportional counters, which provided information about energy spectra of the sources. A constant challenge was determining precise positions of sources as only collimators were available.

Adjustable Grazing-Incidence X-Ray Optics

Science.gov (United States)

O'Dell, Stephen L.; Reid, Paul B.

2015-01-01

With its unique subarcsecond imaging performance, NASA's Chandra X-ray Observatory illustrates the importance of fine angular resolution for x-ray astronomy. Indeed, the future of x-ray astronomy relies upon x-ray telescopes with comparable angular resolution but larger aperture areas. Combined with the special requirements of nested grazing-incidence optics, mass, and envelope constraints of space-borne telescopes render such advances technologically and programmatically challenging. The goal of this technology research is to enable the cost-effective fabrication of large-area, lightweight grazing-incidence x-ray optics with subarcsecond resolution. Toward this end, the project is developing active x-ray optics using slumped-glass mirrors with thin-film piezoelectric arrays for correction of intrinsic or mount-induced distortions.

Bone X-Ray (Radiography)

Medline Plus

Full Text Available ... have special pediatric considerations. The teddy bear denotes child-specific content. Related Articles and Media Radiation Dose in X-Ray and CT Exams Arthritis X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety How to Read Your Radiology Report ...

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 those parts of a patient's body not being imaged receive minimal radiation exposure. ...

Spectral and temporal properties of the X-ray pulsar SMC X-1 at hard X-rays

Science.gov (United States)

Kunz, M.; Gruber, D. E.; Kendziorra, E .; Kretschmar, P.; Maisack, M.; Mony, B.; Staubert, R.; Doebereiner, S.; Englhauser, J.; Pietsch, W.

1993-01-01

The binary X-ray pulsar SMC X- 1 has been observed at hard X-rays with the High Energy X-Ray Experiment (HEXE) on nine occasions between Nov. 1987 and March 1989. A thin thermal bremsstrahlung fit to the phase averaged spectrum yields a plasma temperature (14.4 +/- 1.3) keV and a luminosity above (1.1 +/- 0.1) x 10 exp 38 erg/s in the 20-80 keV band. Pulse period values have been established for three observations, confirming the remarkably stable spin-up trend of SMC X-1. In one of the three observations the pulse profile was seen to deviate from a dominant double pulsation, while at the same time the pulsed fraction was unusually large. For one observation we determined for the first time the pulsed fraction in narrow energy bands. It increases with photon energy from about 20 percent up to over 60 percent in the energy range from 20 to 80 keV.

Benchtop phase-contrast X-ray imaging

Energy Technology Data Exchange (ETDEWEB)

Gundogdu, O. [Department of Physics, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom)], E-mail: o.gundogdu@surrey.ac.uk; Nirgianaki, E.; Che Ismail, E.; Jenneson, P.M.; Bradley, D.A. [Department of Physics, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom)

2007-12-15

Clinical radiography has traditionally been based on contrast obtained from absorption when X-rays pass through the body. The contrast obtained from traditional radiography can be rather poor, particularly when it comes to soft tissue. A wide range of media of interest in materials science, biology and medicine exhibit very weak absorption contrast, but they nevertheless produce significant phase shifts with X-rays. The use of phase information for imaging purposes is therefore an attractive prospect. Some of the X-ray phase-contrast imaging methods require highly monochromatic plane wave radiation and sophisticated X-ray optics. However, the propagation-based phase-contrast imaging method adapted in this paper is a relatively simple method to implement, essentially requiring only a microfocal X-ray tube and electronic detection. In this paper, we present imaging results obtained from two different benchtop X-ray sources employing the free space propagation method. X-ray phase-contrast imaging provides higher contrast in many samples, including biological tissues that have negligible absorption contrast.

The STAR-X X-Ray Telescope Assembly (XTA)

Science.gov (United States)

McClelland, Ryan S.; Bautz, Mark W.; Bonafede, Joseph A.; Miller, Eric D.; Saha, Timo T.; Solly, Peter M.; Zhang, William W.

2017-01-01

The Survey and Time-domain Astrophysical Research eXplorer (STAR-X) science goals are to discover what powers the most violent explosions in the Universe, understand how black holes grow across cosmic time and mass scale, and measure how structure formation heats the majority of baryons in the Universe. To achieve these goals, STAR-X requires a powerful X-ray telescope with a large field of view, large collecting area, and excellent point spread function. The STAR-X instrument, the X-Ray Telescope Assembly (XTA), meets these requirements using a powerful X-ray mirror technology based on precision-polished single crystal silicon and a mature CCD detector technology. The XTA is composed of three major subsystems: an X-ray Mirror Assembly (MA) of high resolution, lightweight mirror segments fabricated out of single crystal silicon; a Focal Plane Assembly (FPA) made of back-illuminated CCD's capable of detecting X-rays with excellent quantum efficiency; and a composite Telescope Tube that structurally links the MA and FPA. The MA consists of 5,972 silicon mirror segments mounted into five subassemblies called meta-shells. A meta-shell is constructed from an annular central structural shell covered with interlocking layers of mirror segments. This paper describes the requirements, design, and analysis of the XTA subsystems with particular focus on the MA.

Special Important Aspects of the Thomson Effect

Science.gov (United States)

Lashkevych, Igor; Velázquez, J. E.; Titov, Oleg Yu.; Gurevich, Yuri G.

2018-03-01

A comprehensive study of the mechanisms of heating and cooling originating from an electrical current in semiconductor devices is reported. The variation in temperature associated with the Peltier effect is not related to the presence of heat sources and sinks if the heat flux is correctly determined. The Thomson effect is commonly regarded as a heat source/sink proportional to the Thomson coefficient, which is added to the Joule heating. In the present work, we will show that this formulation of the Thomson effect is not sufficiently clear. When the heat flux is correctly defined, the Thomson heat source/sink is proportional to the Seebeck coefficient. In the conditions in which the Peltier effect takes place, the temperature gradient is created, and, consequently, the Thomson effect will occur naturally.

Black hole and neutron star soft X-ray transients: a hard X-ray view of their outbursts

International Nuclear Information System (INIS)

Yu, W.

2004-01-01

The RXTE public observations of the outbursts of black hole soft X-ray transients XTE J1550-564, XTE J1859+226, 4U 1630-47, XTE J1118+480, XTE J1650-500, and the neutron star soft X-ray transients 4U 1608-52, Aquila X-1, including a variable 'persistent' neutron star low mass X-ray binary 4U 1705-44, are summarized in this paper. The hard X-ray view of those outbursts, which is quite different from that of the soft X-ray band, suggests that there are several types of outbursts which result in different hard X-ray outburst profile - the outburst profiles are energy dependent. One type is the low/hard state outbursts, the other type is the outburst showing transitions from the low/hard state to the high/soft state, or to the intermediate or to the very high state. The later has an initial low/hard state, introducing the phenomena that the hard X-ray precedes the soft X-ray in the outburst rise. Such outbursts in XTE J1550-564, Aql X-1 and 4U 1705-44 support a two-accretion-flow model which involves one Keplerian disk flow and one sub-Keplerian flow for the initial outburst rise

X-ray Observations at Gaisberg Tower

Directory of Open Access Journals (Sweden)

Pasan Hettiarachchi

2018-01-01

Full Text Available We report the occurrence of X-rays at ground level due to cloud-to-ground flashes of upward-initiated lightning from Gaisberg Tower, in Austria, which is located at an altitude of 1300 m. This is the first observation of X-ray emissions from upward lightning from a tower top located at high altitude. Measurements were carried out using scintillation detectors installed close to the tower top in two phases from 2011 to 2015. X-rays were recorded in three subsequent strokes of three flashes out of the total of 108 flashes recorded in the system during both phases. In contrast to the observations from downward natural or triggered lightning, X-rays were observed only within 10 µs before the subsequent return stroke. This shows that X-rays were emitted when the dart leader was in the vicinity of the tower top, hence during the most intense phase of the dart leader. Both the detected energy and the fluence of X-rays are far lower compared to X-rays from downward natural or rocket-triggered lightning. In addition to the above 108 flashes, an interesting observation of X-rays produced by a nearby downward flash is also presented. The shorter length of dart-leader channels in Gaisberg is suggested as a possible cause of this apparently weaker X-ray production.

Relative probabilities of the uranium isotopes for thorium x-ray emission and fluorescence of uranium x-rays

International Nuclear Information System (INIS)

Parker, J.L.

1991-01-01

Both thorium x-rays from decaying uranium isotopes and self-fluoresced uranium x-rays are prominent in high-resolution gamma-ray spectra of uranium-bearing materials. Useful application of the information carried by those x-rays has been curtailed because the probabilities of the uranium isotopes for thorium x-ray emission and for uranium x-ray fluorescence have not been known. By analyzing enrichment-meter geometry spectra from uranium oxide standards whose enrichments ranged from 0.7% to 91%, relative values, primarily, have been obtained for the probabilities of both processes. Thorium x-ray emission is very heavily dominated by 235 U. In all ordinarily occurring uranium isotopic distributions, thorium x-rays may be used as a valid 235 U signature. The probability for a thorium K α1 x-ray to be emitted in the decay of a 235 U atom is 0.048 ±0.002. In infinitely thick uranium oxide materials, the relative ratios of effectiveness for self-fluorescence, on a per unit mass basis, are approximately 234 U : 235 U : 236 U : 238 U = 1.13 : 1.00 : 0.52 : 0.028. on a per decay basis, the approximate ratios are 0.00039 : 1.00 : 0.017 : 0.18. These results imply that, contrary to what has often been stated, gamma rays are far more important than alpha particles in the self-fluorescence of uranium. Because of the importance of gamma-ray self-fluorescence, the uranium x-ray yield will be somewhat influenced by the size, shape, and composition of the materials. 4 refs., 1 fig

Temporal characteristic analysis of laser-modulated pulsed X-ray source for space X-ray communication

Science.gov (United States)

Hang, Shuang; Liu, Yunpeng; Li, Huan; Tang, Xiaobin; Chen, Da

2018-04-01

X-ray communication (XCOM) is a new communication type and is expected to realize high-speed data transmission in some special communication scenarios, such as deep space communication and blackout communication. This study proposes a high-speed modulated X-ray source scheme based on the laser-to-X-ray conversion. The temporal characteristics of the essential components of the proposed laser-modulated pulsed X-ray source (LMPXS) were analyzed to evaluate its pulse emission performance. Results show that the LMPXS can provide a maximum modulation rate up to 100 Mbps which is expected to significantly improve the data rate of XCOM.

Transforming Our Understanding of the X-ray Universe: The Imaging X-ray Polarimeter Explorer (IXPE)

Science.gov (United States)

Weisskopf, Martin C.; Bellazzini, Ronaldo; Costa, Enrico; Matt, Giorgio; Marshall, Herman; ODell, Stephen L.; Pavlov, George; Ramsey, Brian; Romani, Roger

2014-01-01

Accurate X-ray polarimetry can provide unique information on high-energy-astrophysical processes and sources. As there have been no meaningful X-ray polarization measurements of cosmic sources since our pioneering work in the 1970's, the time is ripe to explore this new parameter space in X-ray astronomy. To accomplish this requires a well-calibrated and well understood system that-particularly for an Explorer mission-has technical, cost, and schedule credibility. The system that we shall present satisfies these conditions, being based upon completely calibrated imaging- and polarization-sensitive detectors and proven X-ray-telescope technology.

Experimental investigations of the dosimetric features of x-ray radiation used in x-ray diagnosis

Energy Technology Data Exchange (ETDEWEB)

Prostyakova, M A

1975-10-01

For radiation hygiene estimates of the extent of the irradiation of various organs and tissues in roentgenological investigations, the quality and quantity of the primary radiation beam and its behaviour in the irradiated medium are assessed. It is shown that the effective energy of x-rays generated at 50-100 kV and with different radiation field dimensions at different depths in a tissue-equivalent irradiated medium is more or less constant, varying within the range 25 to 32 keV. The constancy of effective x-ray energies in a tissue-equivalent medium enables one to use, for different x-ray tube regimes, constant values of the roentgen-rad conversion factor for soft tissue and bone tissue. The investigations confirm the desirability of using high voltages across the x-ray tube in practical x-ray work.

Test facility for astronomical x-ray optics

DEFF Research Database (Denmark)

Christensen, Finn Erland; Lewis, Robert A.; Bordas, J.

1990-01-01

Grazing incidence x-ray optics for x-ray astronomical applications are used outside the earth's atmosphere. These devices require a large collection aperture and the imaging of an x-ray source that is essentially placed at infinity. The ideal testing system for these optical elements has to appro......Grazing incidence x-ray optics for x-ray astronomical applications are used outside the earth's atmosphere. These devices require a large collection aperture and the imaging of an x-ray source that is essentially placed at infinity. The ideal testing system for these optical elements has...... to approximate that encountered under working conditions; however, the testing of these optical elements is notoriously difficult with conventional x-ray generators. Synchrotron radiation (SR) sources are sufficiently brilliant to produce a nearly perfect parallel beam over a large area while still retaining...... a flux considerably higher than that available from conventional x-ray generators. A facility designed for the testing of x-ray optics, particularly in connection with x-ray telescopes, is described. It is proposed that this facility will be accommodated at the Synchrotron Radiation Source...

Discovery of Hard Nonthermal Pulsed X-Ray Emission from the Anomalous X-Ray Pulsar 1E 1841-045

NARCIS (Netherlands)

Kuiper, L.; Hermsen, W.; Méndez, R.M.

2004-01-01

We report the discovery of nonthermal pulsed X-ray/soft gamma-ray emission up to ~150 keV from the anomalous 11.8 s X-ray pulsar AXP 1E 1841-045 located near the center of supernova remnant Kes 73 using Rossi X-Ray Timing Explorer (RXTE) Proportional Counter Array and High Energy X-Ray Timing

X-ray film calibration

International Nuclear Information System (INIS)

Stone, G.F.; Dittmore, C.H.; Henke, B.L.

1986-01-01

This paper discusses the use of silver halide x-ray films for imaging and spectroscopy which is limited by the range of intensities that can be recorded and densitometered. Using the manufacturers processing techniques can result in 10 2-3 range in intensity recorded over 0-5 density range. By modifying the chemistry and processing times, ranges of 10 5-6 can be recorded in the same density range. The authors report on x-ray film calibration work and dynamic range improvements. Changes to the processing chemistry and the resulting changes in dynamic range and x-ray sensitivity are discussed

Picosecond x-ray streak camera studies

International Nuclear Information System (INIS)

Kasyanov, Yu.S.; Malyutin, A.A.; Richardson, M.C.; Chevokin, V.K.

1975-01-01

Some initial results of direct measurement of picosecond x-ray emission from laser-produced plasmas are presented. A PIM-UMI 93 image converter tube, incorporating an x-ray sensitive photocathode, linear deflection, and three stages of image amplification was used to analyse the x-ray radiation emanating from plasmas produced from solid Ti targets by single high-intensity picosecond laser pulses. From such plasmas, the x-ray emission typically persisted for times of 60psec. However, it is shown that this detection system should be capable of resolving x-ray phenomena of much shorter duration. (author)

Bone age assessment by dual-energy X-ray absorptiometry in children: an alternative for X-ray?

Science.gov (United States)

Heppe, D H M; Taal, H R; Ernst, G D S; Van Den Akker, E L T; Lequin, M M H; Hokken-Koelega, A C S; Geelhoed, J J M; Jaddoe, V W V

2012-02-01

The aim of the study was to validate dual-energy X-ray absorptiometry (DXA) as a method to assess bone age in children. Paired dual-energy X-ray absorptiometry (DXA) scans and X-rays of the left hand were performed in 95 children who attended the paediatric endocrinology outpatient clinic of University Hospital Rotterdam, the Netherlands. We compared bone age assessments by DXA scan with those performed by X-ray. Bone age assessment was performed by two blinded observers according to the reference method of Greulich and Pyle. Intra-observer and interobserver reproducibility were investigated using the intraclass correlation coefficient (ICC), and agreement was tested using Bland and Altman plots. The intra-observer ICCs for both observers were 0.997 and 0.991 for X-ray and 0.993 and 0.987 for DXA assessments. The interobserver ICC was 0.993 and 0.991 for X-ray and DXA assessments, respectively. The mean difference between bone age assessed by X-ray and DXA was 0.11 years. The limits of agreement ranged from -0.82 to 1.05 years, which means that 95% of all differences between the methods were covered by this range. Results of bone age assessment by DXA scan are similar to those obtained by X-ray. The DXA method seems to be an alternative for assessing bone age in a paediatric hospital-based population.

Heldi Thomson

Index Scriptorium Estoniae

1997-01-01

Teaduspreemia autorite kollektiivile arstiteaduse alal töö "Vähktõbi Eestis 1968-1992: haigestumus, levimus, elulemus ja suremus" eest - Mati Rahu (kollektiivi juht), Tiiu Aarelaid, Kaja Gornoi, Heldi Thomson

Novel X-ray Communication Based XNAV Augmentation Method Using X-ray Detectors

Directory of Open Access Journals (Sweden)

Shibin Song

2015-09-01

Full Text Available The further development of X-ray pulsar-based NAVigation (XNAV is hindered by its lack of accuracy, so accuracy improvement has become a critical issue for XNAV. In this paper, an XNAV augmentation method which utilizes both pulsar observation and X-ray ranging observation for navigation filtering is proposed to deal with this issue. As a newly emerged concept, X-ray communication (XCOM shows great potential in space exploration. X-ray ranging, derived from XCOM, could achieve high accuracy in range measurement, which could provide accurate information for XNAV. For the proposed method, the measurement models of pulsar observation and range measurement observation are established, and a Kalman filtering algorithm based on the observations and orbit dynamics is proposed to estimate the position and velocity of a spacecraft. A performance comparison of the proposed method with the traditional pulsar observation method is conducted by numerical experiments. Besides, the parameters that influence the performance of the proposed method, such as the pulsar observation time, the SNR of the ranging signal, etc., are analyzed and evaluated by numerical experiments.

X-ray sources

International Nuclear Information System (INIS)

Masswig, I.

1986-01-01

The tkb market survey comparatively evaluates the X-ray sources and replacement tubes for stationary equipment currently available on the German market. It lists the equipment parameters of 235 commercially available X-ray sources and their replacement tubes and gives the criteria for purchase decisions. The survey has been completed with December 1985, and offers good information concerning medical and technical aspects as well as those of safety and maintenance. (orig.) [de

Dilation x-ray imager a new∕faster gated x-ray imager for the NIF.

Science.gov (United States)

Nagel, S R; Hilsabeck, T J; Bell, P M; Bradley, D K; Ayers, M J; Barrios, M A; Felker, B; Smith, R F; Collins, G W; Jones, O S; Kilkenny, J D; Chung, T; Piston, K; Raman, K S; Sammuli, B; Hares, J D; Dymoke-Bradshaw, A K L

2012-10-01

As the yield on implosion shots increases it is expected that the peak x-ray emission reduces to a duration with a FWHM as short as 20 ps for ∼7 × 10(18) neutron yield. However, the temporal resolution of currently used gated x-ray imagers on the NIF is 40-100 ps. We discuss the benefits of the higher temporal resolution for the NIF and present performance measurements for dilation x-ray imager, which utilizes pulse-dilation technology [T. J. Hilsabeck et al., Rev. Sci. Instrum. 81, 10E317 (2010)] to achieve x-ray imaging with temporal gate times below 10 ps. The measurements were conducted using the COMET laser, which is part of the Jupiter Laser Facility at the Lawrence Livermore National Laboratory.

X-ray image intensifier tube

International Nuclear Information System (INIS)

1981-01-01

An improved real-time x-ray image intensifier tube of the proximity type used for medical x-ray fluoroscopy is described. It is claimed that this intensifier is of sufficient gain and resolution whilst remaining convenient to use and that the design is such that the patient dosage is minimized whilst the x-ray image information content at the scintillator-photocathode screen is maximized. (U.K.)

JEM-X: The X-ray monitor aboard INTEGRAL

DEFF Research Database (Denmark)

Lund, Niels; Budtz-Jørgensen, Carl; Westergaard, Niels Jørgen Stenfeldt

2003-01-01

The JEM-X monitor provides X-ray spectra and imaging with arcminute angular resolution in the 3 to 35 keV band. The good angular resolution and the low energy response of JEM-X plays an important role in the identification of gamma ray sources and in the analysis and scientific interpretation...

Design of the divertor Thomson scattering system on DIII-D

International Nuclear Information System (INIS)

Carlstrom, T.N.; Foote, J.H.; Nilson, D.G.; Rice, B.W.

1994-05-01

Local measurements of n e and T e in the divertor region are necessary for a more complete understanding of divertor physics. We have designed an extension to the existing multipulse Thomson scattering system to measure n e in the range 5 x 10 18 to 5 x 10 20 m -3 and T e 5--500 eV, with 1 cm resolution from 1--21 cm above the floor of the DIII-D vessel, in the region of the X-point for lower single-null diverted plasmas. One of the existing 8, 20 Hz, ND:YAG lasers will be redirected to a separate vertical port, and viewed radially with a specially designed, f/6.8 lens. Fiber optics carry the light to additional polychromators whose interference filters have been optimized for low T e measurements. Other aspect of the system, including the beam path to the vessel, polychromator design, real time data acquisition, laser control, calibration facility, and DIII-D timing and data acquisition interface will be shared with the existing multipulse Thomson system. An in-situ laser alignment monitor will provide alignment information for each laser pulse

SphinX x-ray spectrophotometer

Science.gov (United States)

Kowaliński, Mirosław

2012-05-01

This paper presents assumptions to a PhD thesis. The thesis will be based on the construction of Solar Photometer in X-rays (SphinX). SphinX was an instrument developed to detect the soft X-rays from the Sun. It was flown on board the Russian CORONAS-Photon satellite from January 30, 2009 to the end of November, 2009. During 9 months in orbit SphinX provided an excellent and unique set of observations. It revealed about 750 flares and brightenings. The instrument observed in energy range 1.0 - 15.0 keV with resolution below ~0.5 keV. Here, the SphinX instrument objectives, design, performance and operation principle are described. Below results of mechanical and thermal - vacuum tests necessary to qualify the instrument to use in space environment are presented. Also the calibration results of the instrument are discussed. In particular detail it is described the Electrical Ground Support Equipment (EGSE) for SphinX. The EGSE was used for all tests of the instrument. At the end of the paper results obtained from the instrument during operation in orbit are discussed. These results are compared with the other similar measurements performed from the separate spacecraft instruments. It is suggested design changes in future versions of SphinX.

Bone X-Ray (Radiography)

Medline Plus

Full Text Available ... have very controlled x-ray beams and dose control methods to minimize stray (scatter) radiation. This ensures that those parts of a patient's body not being imaged receive minimal radiation exposure. top of page What are the limitations of Bone X-ray (Radiography)? ...

CubeX: The CubeSAT X-ray Telescope for Elemental Abundance Mapping of Airless Bodies and X-ray Pulsar Navigation

Science.gov (United States)

Nittler, L. R.; Hong, J.; Kenter, A.; Romaine, S.; Allen, B.; Kraft, R.; Masterson, R.; Elvis, M.; Gendreau, K.; Crawford, I.; Binzel, R.; Boynton, W. V.; Grindlay, J.; Ramsey, B.

2017-12-01

The surface elemental composition of a planetary body provides crucial information about its origin, geological evolution, and surface processing, all of which can in turn provide information about solar system evolution as a whole. Remote sensing X-ray fluorescence (XRF) spectroscopy has been used successfully to probe the major-element compositions of airless bodies in the inner solar system, including the Moon, near-Earth asteroids, and Mercury. The CubeSAT X-ray Telescope (CubeX) is a concept for a 6U planetary X-ray telescope (36U with S/C), which utilizes Miniature Wolter-I X-ray optics (MiXO), monolithic CMOS and SDD X-ray sensors for the focal plane, and a Solar X-ray Monitor (heritage from the REXIS XRF instrument on NASA's OSIRIS-REx mission). CubeX will map the surface elemental composition of diverse airless bodies by spectral measurement of XRF excited by solar X-rays. The lightweight ( 1 kg) MiXO optics provide sub-arcminute resolution with low background, while the inherently rad-hard CMOS detectors provide improved spectral resolution ( 150 eV) at 0 °C. CubeX will also demonstrate X-ray pulsar timing based deep space navigation (XNAV). Successful XNAV will enable autonomous deep navigation with little to no support from the Deep Space Network, hence lowering the operation cost for many more planetary missions. Recently selected by NASA Planetary Science Deep Space SmallSat Studies, the first CubeX concept, designed to rideshare to the Moon as a secondary spacecraft on a primary mission, is under study in collaboration with the Mission Design Center at NASA Ames Research Center. From high altitude ( 6,000 km) frozen polar circular orbits, CubeX will study > 8 regions ( 110 km) of geological interest on the Moon over one year to produce a high resolution ( 2-3 km) elemental abundance map of each region. The novel focal plane design of CubeX also allows us to evaluate the performance of absolute navigation by sequential observations of several

X-ray radiotherapy

International Nuclear Information System (INIS)

Tronc, D.

1995-01-01

Full text: The most common form of radio therapy is X-ray therapy, where a beam of photons or their parent electrons break down hydrogen bonds within the body's cells and remove certain DNA information necessary for cell multiplication. This process can eradicate malignant cells leading to complete recovery, to the remission of some cancers, or at least to a degree of pain relief. The radiotherapy instrument is usually an electron linac, and the electrons are used either directly in 'electrotherapy' for some 10% of patients, or the electrons bombard a conversion target creating a broad beam of high energy photons or 'penetration X-rays'. The simplest machine consists of several accelerating sections at around 3 GHz, accelerating electrons to 6 MeV; a cooled tungsten target is used to produce a 4 Gray/min X-ray field which can be collimated into a rectangular shape at the patient position. This tiny linac is mounted inside a rotating isocentric gantry above the patient who must remain perfectly still. Several convergent beams can also be used to increase the delivered dose. More sophisticated accelerators operate at up to 18 MeV to increase penetration depths and decrease skin exposure. Alternatively, electrotherapy can be used with different energies for lower and variable penetration depths - approximately 0.5 cm per MeV. In this way surface tissue may be treated without affecting deeper and more critical anatomical regions. This type of linac, 1 to 2 metres long, is mounted parallel to the patient with a bending magnet to direct the beam to the radiotherapy system, which includes the target, thick movable collimator jaws, a beam field equalizer, dose rate and optical field simulation and energy controls. There are over 2000 acceleratorbased X-ray treatment units worldwide. Western countries have up to two units per million population, whereas in developing countries such as Bangladesh, the density is only one per 100 million. Several

X-ray bursters and the X-ray sources of the galactic bulge

International Nuclear Information System (INIS)

Lewin, W.H.G.; Joss, P.C.; Massachusetts Inst. of Tech., Cambridge; Massachusetts Inst. of Tech., Cambridge

1981-01-01

In this article we shall discuss the observed X-ray, optical, infrared and radio properties of the galactic bulge sources, with an emphasis on those that produce type I X-ray bursts. There is persuasive evidence that these burst sources and many other galactic bulge sources are neutron stars in low-mass, close-binary stellar systems. (orig./WL)

X-ray area monitor

International Nuclear Information System (INIS)

Nintrakit, N.

1983-01-01

The X-ray area monitor is a nuclear electronic device that is essential in radiation protection in high radiation laboratories, e.g. in medical diagnosis using X-rays and in industrial X-radiography. Accidentally the level of X-radiator may arise above the safe permissible level and in such a case the alarm system of the area monitor will work and disconnect the ac power supply form the X-ray unit. Principally the device is a radiation counter using G.M.tube as radiation detector with high voltage supply variable form 200 to 2,000 volts. The maximum count rate of the scaler is 1.5 MHz and the total count is displayed on 4 digit LED's. A time base is used to control the counting time, the frequency multiplier, radiation safety limit, comparator and the radiation hazard warning signal. The reliability of the instrument is further enhanced through the addition of the random correction circuit, and it is applicable both in X- and γ -radiation

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.

Dilation x-ray imager a new/faster gated x-ray imager for the NIF [DIXI (Dilation x-ray imager) a new/faster gated x-ray imager for the NIF

Energy Technology Data Exchange (ETDEWEB)

Nagel, S. R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hilsabeck, T. J.; Bell, P. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Bradley, D. K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ayers, M. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Barrios, M. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Felker, B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Smith, R. F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Collins, G. W. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Jones, O. S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kilkenny, J. D. [General Atomics, San Diego, CA (United States); Chung, T. [General Atomics, San Diego, CA (United States); Piston, K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Raman, K. S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Sammuli, B. [General Atomics, San Diego, CA (United States); Hares, J. D. [Kentech Instruments Ltd., Wallingford, Oxfordshire (United Kingdom); Dymoke-Bradshaw, A. K. L. [Kentech Instruments Ltd., Wallingford, Oxfordshire (United Kingdom)

2012-07-19

As the yield on implosion shots increases it is expected that the peak x-ray emission reduces to a duration with a FWHM as short as 20 ps for ~7 10¹⁸ neutron yield. However, the temporal resolution of currently used gated x-ray imagers on the NIF is 40-100 ps. We discuss the benefits of the higher temporal resolution for the NIF and present performance measurements for DIXI, which utilizes pulse-dilation technology [1] to achieve x-ray imaging with temporal gate times below 10 ps. Lastly, the measurements were conducted using the COMET laser, which is part of the Jupiter Laser Facility at the Lawrence Livermore National Laboratory.

Repeated pulsed x-ray emission equipment

International Nuclear Information System (INIS)

Terauchi, Hikaru; Iida, Satoshi

1982-01-01

X-ray diffraction technique has been applied to determine the spatial positions of atoms which compose a material, and it is needless to say that the technique is a fundamental means regardless of the fields of research. However, the application of X-ray diffraction to the research on physical properties has been so far limited to know the spatial positions of atoms or molecules under thermal equilibrium condition. The addition of time element to the conventional technique, that is, the analysis of material structure including the time-varying processes under non-equilibrium conditions, is considered to approach the elucidation of the essence of materials. The authors call this dynamic structural analysis. The authors have planned to analyze X-ray diffraction intensity which has the resolution of about 10 -8 s in the real time which is conjugate with energy. However, present pulsed X-ray sources are not suitable for diffraction experiment because the pulse width is too long or X-ray wavelength is too short. Accordingly, the authors have made for trial a pulsed X-ray source for diffraction experiment. Its specifications are: diode voltage (X-ray tube voltage) from 200 to 300 kV, diode current from 2 to 5 kA, pulse width of about 30ns, maximum repetition frequency 10 pps, and X-ray focus size of 2 mm diameter. One of the features of this source is the repeated generation of pulsed X-ray. This is the first trial in the world, and is indispensable to the dynamic structural analysis described above. The quality of the emitted X-ray is also written. (Wakatsuki, Y.)

Origin of the cosmic x-ray background

International Nuclear Information System (INIS)

Margon, B.

1983-01-01

Since 1962, it has been known that every part of the sky emits a uniform glow of x-rays. After two decades of intense study the origin of this diffuse x-ray background is still a subject of controversy. The near perfect isotropy of the x-ray background is clearly a vital clue to its origin. A second clue to the origin of the x-ray background arises from the fact that it is x-radiation tha is generated, rather than some longer wavelength radiation. Two hypotheses of the origin of this x-ray background are discussed. One hypothesis is that the x-ray background can be attributed to bremsstrahlung from a hot intergalactic medium. The second hypothesis is that the x-ray background originates from a large number of quasars. Because there is no estimate independent of the intensity of the x-ray background of how much hot intergalactic medium exists (if any), there is a real possibility that both sources contribute to the observed x-rays. (SC)

Development and applications of grazing exit micro X-ray fluorescence instrument using a polycapillary X-ray lens

International Nuclear Information System (INIS)

Emoto, T.; Sato, Y.; Konishi, Y.; Ding, X.; Tsuji, K.

2004-01-01

A polycapillary X-ray lens is an effective optics to obtain a μm-size X-ray beam for micro-X-ray fluorescence spectrometry (μ-XRF). We developed a μ-XRF instrument using a polycapillary X-ray lens, which also enabled us to perform Grazing Exit μ-XRF (GE-μ-XRF). The evaluated diameter of the primary X-ray beam was 48 μm at the focal distance of the X-ray lens. Use of this instrument enabled two-dimensional mapping of the elemental distributions during growth of the plant 'Quinoa'. The results of the mapping revealed elemental transition during growth. In addition, a small region of thin film was analyzed by GE-μ-XRF. We expect that GE-μ-XRF will become an effective method of estimating the film thickness of a small region

X-ray scattering by interstellar dust

International Nuclear Information System (INIS)

Rolf, D.

1980-10-01

This thesis reports work carried out to make a first observation of x-rays scattered by interstellar dust grains. Data about the dust, obtained at wavelengths ranging from the infrared to ultra-violet spectral regions, are discussed in order to establish a useful description of the grains themselves. This is then used to estimate the magnitude and form of the expected x-ray scattering effect which is shown to manifest itself as a diffuse halo accompanying the image of a celestial x-ray source. Two x-ray imaging experiments are then discussed. The first, specifically proposed to look for this effect surrounding a point x-ray source, was the Skylark 1611 project, and comprised an imaging proportional counter coupled to an x-ray mirror. This is described up to its final calibration when the basis for a concise model of its point response function was established. The experiment was not carried out but its objective and the experience gained during its testing were transferred to the second of the x-ray imaging experiments, the Einstein Observatory. The new instrumental characteristics are described and a model for its point response function is developed. Using this, image data for the point x-ray source GX339-4 is shown to exhibit the sought after scattering phenomenon. (author)

Technological Challenges to X-Ray FELs

Energy Technology Data Exchange (ETDEWEB)

Nuhn, Heinz-Dieter

1999-09-16

There is strong interest in the development of x-ray free electron lasers (x-ray FELs). The interest is driven by the scientific opportunities provided by intense, coherent x-rays. An x-ray FEL has all the characteristics of a fourth-generation source: brightness several orders of magnitude greater than presently achieved in third-generation sources, full transverse coherence, and sub-picosecond long pulses. The SLAC and DESY laboratories have presented detailed design studies for X-Ray FEL user facilities around the 0.1 nm wavelength-regime (LCLS at SLAC, TESLA X-Ray FEL at DESY). Both laboratories are engaged in proof-of-principle experiments are longer wavelengths (TTF FEL Phase I at 71 nm, VISA at 600-800 nm) with results expected in 1999. The technologies needed to achieve the proposed performances are those of bright electron sources, of acceleration systems capable of preserving the brightness of the source, and of undulators capable of meeting the magnetic and mechanical tolerances that are required for operation in the SASE mode. This paper discusses the technological challenges presented by the X-Ray FEL projects.

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.

X-ray tube monitor apparatus

International Nuclear Information System (INIS)

Holland, W.P.; Pellergrino, A.

1981-01-01

An x-ray tube with a rotating anode target is provided with a detector of x-rays located outside a port of a housing of the tube and positioned at or near a tangent line to the radiating surface for observing variations in the radiation intensity due to rotation of the target, the variations being pronounced due to the heel effect of the radiation pattern. The x-ray detector can employ a scintillation material and be coupled by a light guide to a photodetector which is removed from the path of the radiation and detects scintillations of the x-ray detector. Alternatively, the photodetector and light pipe may be replaced by a detector of germanium, silicon or an ion chamber which converts x-ray photons directly to an electric current. An electronic unit determines the speed of rotation from the electric signal and can also, by fourier transform and signature analysis techniques, monitor the state of the radiating surface. (author)

X-ray spectroscopy an introduction

CERN Document Server

Agarwal, Bipin K

1979-01-01

Rontgen's discovery of X-rays in 1895 launched a subject which became central to the development of modern physics. The verification of many of the predic­ tions of quantum theory by X-ray spectroscopy in the early part of the twen­ tieth century stimulated great interest in thi's area, which has subsequently influenced fields as diverse as chemical physics, nuclear physics, and the study of the electronic properties of solids, and led to the development of techniques such as Auger, Raman, and X-ray photoelectron spectroscopy. The improvement of the theoretical understanding of the physics underlying X-ray spectroscopy has been accompanied by advances in experimental techniques, and the subject provides an instructive example of how progress on both these fronts can be mutually beneficial. This book strikes a balance between his­ torical description, which illustrates this symbiosis, and the discussion of new developments. The application of X-ray spectroscopic methods to the in­ vestigation of chemical b...

X-ray metrology for ULSI structures

International Nuclear Information System (INIS)

Bowen, D. K.; Matney, K. M.; Wormington, M.

1998-01-01

Non-destructive X-ray metrological methods are discussed for application to both process development and process control of ULSI structures. X-ray methods can (a) detect the unacceptable levels of internal defects generated by RTA processes in large wafers, (b) accurately measure the thickness and roughness of layers between 1 and 1000 nm thick and (c) can monitor parameters such as crystallographic texture and the roughness of buried interfaces. In this paper we review transmission X-ray topography, thin film texture measurement, grazing-incidence X-ray reflectivity and high-resolution X-ray diffraction. We discuss in particular their suitability as on-line sensors for process control

Center for X-ray Optics, 1988

International Nuclear Information System (INIS)

1989-04-01

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

X-ray data booklet. Revision

Energy Technology Data Exchange (ETDEWEB)

Vaughan, D. (ed.)

1986-04-01

A compilation of data is presented. Included are properties of the elements, electron binding energies, characteristic x-ray energies, fluorescence yields for K and L shells, Auger energies, energy levels for hydrogen-, helium-, and neonlike ions, scattering factors and mass absorption coefficients, and transmission bands of selected filters. Also included are selected reprints on scattering processes, x-ray sources, optics, x-ray detectors, and synchrotron radiation facilities. (WRF)

X-ray emission from comets

International Nuclear Information System (INIS)

Dennerl, Konrad

1999-01-01

When comet Hyakutake (C/1996 B2) encountered Earth in March 1996 at a minimum distance of only 15 million kilometers (40 times the distance of the moon), x-ray and extreme ultraviolet emission was discovered for the first time from a comet. The observations were performed with the astronomy satellites ROSAT and EUVE. A systematic search for x-rays from comets in archival data, obtained during the ROSAT all-sky survey in 1990/91, resulted in the discovery of x-ray emission from four additional comets. They were detected at seven occasions in total, when they were optically 300 to 30 000 times fainter than Hyakutake. These findings indicated that comets represent a new class of celestial x-ray sources. Subsequent detections of x-ray emission from additional comets with the satellites ROSAT, EUVE, and BeppoSAX confirmed this conclusion. The x-ray observations have obviously revealed the presence of a process in comets which had escaped attention until recently. This process is most likely charge exchange between highly charged heavy ions in the solar wind and cometary neutrals. The solar wind, a stream of particles continuously emitted from the sun with ≅ 400 km s -1 , consists predominantly of protons, electrons, and alpha particles, but contains also a small fraction (≅0.1%) of highly charged heavier ions, such as C 6+ ,O 6+ ,Ne 8+ ,Si 9+ ,Fe 11+ . When these ions capture electrons from the cometary gas, they attain highly excited states and radiate a large fraction of their excitation energy in the extreme ultraviolet and x-ray part of the spectrum. Charge exchange reproduces the intensity, the morphology and the spectrum of the observed x-ray emission from comets very well

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.

Extragalactic Hard X-ray Surveys: From INTEGRAL to Simbol-X

Science.gov (United States)

Paltani, S.; Dwelly, T.; Walter, R.; McHardy, I. M.; Courvoisier, T. J.-L.

2009-05-01

We present some results of the deepest extragalactic survey performed by the INTEGRAL satellite. The fraction of very absorbed AGN is quite large. The sharp decrease in the absorption fraction with X-ray luminosity observed at lower-energy X-rays is not observed. The current lack of truly Compton-thick objects, with an upper limit of 14% to the size of this population, is just compatible with recent modeling of the cosmic X-ray background. We also study the prospects for a future hard X-ray serendipitous survey with Simbol-X. We show that Simbol-X will easily detect a large number of serendipitous AGN, allowing us to study the evolution of AGN up to redshifts about 2, opening the door to the cosmological study of hard X-ray selected AGN, which is barely possible with existing satellites like Swift and INTEGRAL.

Correlation between X-ray and high energy gamma-ray emission form Cygnus X-3

International Nuclear Information System (INIS)

Weekes, T.C.; Danaher, S.; Fegan, D.J.; Porter, N.A.

1981-01-01

In May-June 1980, the 4.8 hour modulated X-ray flux from Cygnus X-3 underwent a significant change in the shape of the light curve; this change correlates with the peak in the high-energy (E > 2 x 10 12 eV) gamma ray emission at the same epoch. (orig.)

Swift-XRT detects X-ray burst from Circinus X-1

NARCIS (Netherlands)

Linares, M.; Soleri, P.; Altamirano, D.; Armas-Padilla, M.; Cavecchi, Y.; Degenaar, N.; Kalamkar, M.; Kaur, R.; van der Klis, M.; Patruno, A.; Watts, A.; Wijnands, R.; Yang, Y.; Casella, P.; Rea, N.; Chakrabarty, D.; Homan, J.

Following the recent re-brightening (ATel #2608) and RXTE-PCA detection of X-ray bursts from the peculiar X-ray binary Cir X-1 between May 15 and 25 (ATel #2643), we obtained a series of Swift-XRT observations of the field (see also ATel #2650). Swift-XRT detected an X-ray burst on 2010-05-28 at

Dilation x-ray imager a new/faster gated x-ray imager for the NIF

Energy Technology Data Exchange (ETDEWEB)

Nagel, S. R.; Bell, P. M.; Bradley, D. K.; Ayers, M. J.; Barrios, M. A.; Felker, B.; Smith, R. F.; Collins, G. W.; Jones, O. S.; Piston, K.; Raman, K. S. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550 (United States); Hilsabeck, T. J.; Kilkenny, J. D.; Chung, T.; Sammuli, B. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States); Hares, J. D.; Dymoke-Bradshaw, A. K. L. [Kentech Instruments Ltd., Wallingford, Oxfordshire OX10 (United Kingdom)

2012-10-15

As the yield on implosion shots increases it is expected that the peak x-ray emission reduces to a duration with a FWHM as short as 20 ps for {approx}7 Multiplication-Sign 10{sup 18} neutron yield. However, the temporal resolution of currently used gated x-ray imagers on the NIF is 40-100 ps. We discuss the benefits of the higher temporal resolution for the NIF and present performance measurements for dilation x-ray imager, which utilizes pulse-dilation technology [T. J. Hilsabeck et al., Rev. Sci. Instrum. 81, 10E317 (2010)] to achieve x-ray imaging with temporal gate times below 10 ps. The measurements were conducted using the COMET laser, which is part of the Jupiter Laser Facility at the Lawrence Livermore National Laboratory.

Time-resolved suprathermal x-rays

International Nuclear Information System (INIS)

Lee, P.H.Y.; Rosen, M.D.

1978-01-01

Temporally resolved x-ray spectra in the range of 1 to 20 keV have been obtained from gold disk targets irradiated by 1.06 μm laser pulses from the Argus facility. The x-ray streak camera used for the measurement has been calibrated for streak speed and dynamic range by using an air-gap Fabry-Perot etalon, and the instrument response has been calibrated using a multi-range monoenergetic x-ray source. The experimental results indicate that we are able to observe the ''hot'' x-ray temperature evolve in time and that the experimentally observed values can be qualitatively predicted by LASNEX code computations when the inhibited transport model is used

14th International Conference on X-Ray Lasers

CERN Document Server

Menoni, Carmen; Marconi, Mario

2016-01-01

These proceedings comprise invited and contributed papers presented at the 14th International Conference on X-Ray Lasers (ICXRL 2014). This conference is part of a continuing series dedicated to recent developments and applications of x-ray lasers and other coherent x-ray sources with attention to supporting technologies and instrumentation. New results in the generation of intense, coherent x-rays and progress toward practical devices and their applications in numerous fields are reported. Areas of research in plasma-based x-ray lasers, 4th generation accelerator-based sources and higher harmonic generation, and other x-ray generation schemes are covered.  The scope of ICXRL 2014 included, but was not limited to: Laser-pumped X-ray lasers Discharge excitation and other X-ray laser pumping methods Injection/seeding of X-ray amplifiers New lasing transitions and novel X-ray laser schemes High Harmonic sources-Free-electron laser generation in the XUV and X-ray range Novel schemes for coherent XUV and X-ray ge...

Women and x-rays

Energy Technology Data Exchange (ETDEWEB)

Dunkley, P A; Stewart, J H

1976-01-01

When a woman comes to an X-Ray Department it is usually necessary to know the present stage of her menstrual cycle. X-Rays may have an adverse effect on the embryo, especially in early pregnancy. However, exposure to X-Rays at any stage may be associated with a slightly increased incidence of malignant disease in childhood. The International Commission on Radiological Protection recommends that in women of child-bearing age (in some cases as young as 11 years), non-urgent diagnostic radiography be confined to the preovulatory phase of the menstrual cycle: that is, 14 days following the first day of the last menstrual period.

X-ray photoelectron spectroscopy

International Nuclear Information System (INIS)

Attekum, P.M.T.M. van.

1979-01-01

The methods and results of X-ray photoelectron spectroscopy in the study of plasmons, alloys and gold compounds are discussed. After a comprehensive introduction, seven papers by the author, previously published elsewhere, are reprinted and these cover a wide range of the uses of X-ray photoelectron spectroscopy. (W.D.L.)

Traditional x-ray imaging

International Nuclear Information System (INIS)

Hay, G.A.

1982-01-01

Methods of imaging x-rays, with particular reference to medicine, are reviewed. The history and nature of x-rays, their production and spectra, contrast, shapes and fine structure, image transducers, including fluorescent screens, radiography, fluoroscopy, and image intensifiers, image detection, perception and enhancement and clinical applications are considered. (U.K.)

Bone X-Ray (Radiography)

Medline Plus

Full Text Available ... are a form of radiation like light or radio waves. X-rays pass through most objects, including the body. Once it is carefully aimed at the part of the body being examined, an x-ray machine produces a small burst of radiation that passes through the body, recording ...

Human soft tissue analysis using x-ray or gamma-ray techniques

International Nuclear Information System (INIS)

Theodorakou, C; Farquharson, M J

2008-01-01

This topical review is intended to describe the x-ray techniques used for human soft tissue analysis. X-ray techniques have been applied to human soft tissue characterization and interesting results have been presented over the last few decades. The motivation behind such studies is to provide improved patient outcome by using the data obtained to better understand a disease process and improve diagnosis. An overview of theoretical background as well as a complete set of references is presented. For each study, a brief summary of the methodology and results is given. The x-ray techniques include x-ray diffraction, x-ray fluorescence, Compton scattering, Compton to coherent scattering ratio and attenuation measurements. The soft tissues that have been classified using x-rays or gamma rays include brain, breast, colon, fat, kidney, liver, lung, muscle, prostate, skin, thyroid and uterus. (topical review)

J. J. Thomson and the Discovery of the Electron

Science.gov (United States)

Squires, Gordon

1997-04-01

Joseph John Thomson (1856-1940) was appointed to the Chair of Experimental Physics in the Cavendish Laboratory at the University of Cambridge at the age of 28 and started research on the conduction of electricity through gases at low pressure. He studied the properties of the rays emanating from the cathode in a gas discharge by deflecting them with electric and magnetic fields, and in 1897 announced that they were negatively charged particles about 2000 times lighter than hydrogen atoms, the lightest particles then known. Further, the mass of the particles was the same, irrespective of the nature of the gas in the discharge tube and the material of the cathode. He concluded that he had found a new particle, a universal constituent of matter. The discovery of the particle, subsequently called the electron, was one of the most significant events in the history of science. The talk will give a brief account of Thomson's career and the experiments leading to the discovery.

X-ray lenses with large aperture

International Nuclear Information System (INIS)

Simon, Markus

2010-01-01

Up to now, most X-ray imaging setups are based on absorption contrast imaging. There is a demand for focused X-rays in many X-ray analysis applications, either to increase the resolution of an imaging system, or, to reduce the time effort of an experiment through higher photon flux. For photon energies higher than 15 keV refractive X-ray optics are more efficient in comparison to non-refractive X-ray optics. The aim of this work was to develop X-ray lenses with large apertures and high transparency. By increasing the number of refracting surfaces while removing unnecessary lens material such lenses have been developed. Utilizing this approach the overall beam deflection angle is large with respect to the lens material it propagates through and so the transparency of the lens is increased. Within this work, X-ray lenses consisting of several thousands of prisms with an edge length in the range of micrometers have been developed and fabricated by deep X-ray lithography. Deep X-ray lithography enables high precision microstrucures with smooth sidewalls and large aspect ratios. The aperture of high-transparency X-ray lenses made this way is greater than 1 mm. They are suitable for photon energies in the range of 8 keV to 24 keV and offer a focal width of smaller than 10 μm at a transparency of around 40%. Furthermore, rolled X-ray lenses have been developed, that are made out of a microstructured polyimide film, which is cut according to the requirements regarding focal length and photon energy. The microstructured film is fabricated by molding, using an anisotropically etched silicon wafer as molding tool. Its mean roughness is in the range of nanometers. The film features prismatic structures, its surface topology is similar to an asparagus field. The measured diameter of the point focus was 18 μm to 31 μm, the calculated opticla efficiency was 37%. Future work will concentrate on increasing the aspect ratio of Prism Lenses and on increasing the rolling accuracy

X-Ray analysis and methods for nondestructive control (On the 100-anniversary of X-ray foundation)

International Nuclear Information System (INIS)

Sosnin, F.R.

1995-01-01

Brief consideration is given to the history of X-ray discovery, formation of domestic X-ray industry. Principles of operation and potentialities of X-ray diffraction analysis, gammagraphy, radioscopy, radiometric analysis are described briefly. Domestic and foreign scientists, institutes and companies who contributed much to development of methods for nondestructive control are listed

Development and applications of grazing exit micro X-ray fluorescence instrument using a polycapillary X-ray lens

Energy Technology Data Exchange (ETDEWEB)

Emoto, T.; Sato, Y.; Konishi, Y.; Ding, X.; Tsuji, K. E-mail: tsuji@a-chem.eng.osaka-cu.ac.jp

2004-08-31

A polycapillary X-ray lens is an effective optics to obtain a {mu}m-size X-ray beam for micro-X-ray fluorescence spectrometry ({mu}-XRF). We developed a {mu}-XRF instrument using a polycapillary X-ray lens, which also enabled us to perform Grazing Exit {mu}-XRF (GE-{mu}-XRF). The evaluated diameter of the primary X-ray beam was 48 {mu}m at the focal distance of the X-ray lens. Use of this instrument enabled two-dimensional mapping of the elemental distributions during growth of the plant 'Quinoa'. The results of the mapping revealed elemental transition during growth. In addition, a small region of thin film was analyzed by GE-{mu}-XRF. We expect that GE-{mu}-XRF will become an effective method of estimating the film thickness of a small region.

Development of quantitative x-ray microtomography

International Nuclear Information System (INIS)

Deckman, H.W.; Dunsmuir, J.A.; D'Amico, K.L.; Ferguson, S.R.; Flannery, B.P.

1990-01-01

The authors have developed several x-ray microtomography systems which function as quantitative three dimensional x-ray microscopes. In this paper the authors describe the evolutionary path followed from making the first high resolution experimental microscopes to later generations which can be routinely used for investigating materials. Developing the instrumentation for reliable quantitative x-ray microscopy using synchrotron and laboratory based x-ray sources has led to other imaging modalities for obtaining temporal and spatial two dimensional information

X-ray spot film device

International Nuclear Information System (INIS)

1981-01-01

Improvements are described in an X-ray spot film device which is used in conjunction with an X-ray table to make a selected number of radiographic exposures on a single film and to perform fluoroscopic examinations. To date, the spot film devices consist of two X-ray field defining masks, one of which is moved manually. The present device is more convenient to use and speeds up the procedure. (U.K.)

Marriage of x-ray and optical astronomy

International Nuclear Information System (INIS)

McClintock, J.E.

1975-01-01

An historical discussion of the relation of x-ray and optical astronomy is given including distances within our galaxy, the optical identification of x-ray sources, the binary x-ray stars, neutron stars and black holes, a program in x-ray astronomy, and future missions

X-ray Ordinance

International Nuclear Information System (INIS)

Kramer, R.; Zerlett, G.

1983-01-01

This commentary, presented as volume 2 of the Deutsches Strahlenschutzrecht (German legislation on radiation protection) deals with the legal provisions of the ordinance on the protection against harmful effects of X-radiation (X-ray Ordinance - RoeV), of March 1, 1973 (announced in BGBl.I, page 173), as amended by the ordinance on the protection against harmful effects of ionizing radiation, of October 13, 1976 (announced in BGBl. I, page 2905). Thus volume 2 completes the task started with volume 1, namely to present a comprehensive view and account of the body of laws governing radiation protection, a task which was thought useful as developments in the FRG led to regulations being split up into the X-ray Ordinance, and the Radiation Protection Ordinance. In order to present a well-balanced commentary on the X-ray Ordinance, it was necessary to discuss the provisions both from the legal and the medical point of view. This edition takes into account the Fourth Public Notice of the BMA (Fed. Min. of Labour and Social Affairs) concerning the implementation of the X-ray Ordinance of January 4, 1982, as well as court decisions and literature published in this field, until September 1982. In addition, the judgment of the Federal Constitutional Court, dated October 19, 1982, concerning the voidness of the law on government liability, and two decisions by the Federal High Court, dated November 23, 1982, concerning the right to have insight into medical reports - of great significance in practice - have been considered. This commentary therefore is up to date with current developments. (orig.) [de

Bone X-Ray (Radiography)

Medline Plus

Full Text Available ... body. Once it is carefully aimed at the part of the body being examined, an x-ray machine produces a small burst of radiation that passes through the body, recording an image on photographic film or a special detector. Different parts of the body absorb the x-rays in ...

Weak hard X-ray emission from broad absorption line quasars: evidence for intrinsic X-ray weakness

International Nuclear Information System (INIS)

Luo, B.; Brandt, W. N.; Scott, A. E.; Alexander, D. M.; Gandhi, P.; Stern, D.; Teng, S. H.; Arévalo, P.; Bauer, F. E.; Boggs, S. E.; Craig, W. W.; Christensen, F. E.; Comastri, A.; Farrah, D.; Hailey, C. J.; Harrison, F. A.; Koss, M.; Ogle, P.; Puccetti, S.; Saez, C.

2014-01-01

We report NuSTAR observations of a sample of six X-ray weak broad absorption line (BAL) quasars. These targets, at z = 0.148-1.223, are among the optically brightest and most luminous BAL quasars known at z < 1.3. However, their rest-frame ≈2 keV luminosities are 14 to >330 times weaker than expected for typical quasars. Our results from a pilot NuSTAR study of two low-redshift BAL quasars, a Chandra stacking analysis of a sample of high-redshift BAL quasars, and a NuSTAR spectral analysis of the local BAL quasar Mrk 231 have already suggested the existence of intrinsically X-ray weak BAL quasars, i.e., quasars not emitting X-rays at the level expected from their optical/UV emission. The aim of the current program is to extend the search for such extraordinary objects. Three of the six new targets are weakly detected by NuSTAR with ≲ 45 counts in the 3-24 keV band, and the other three are not detected. The hard X-ray (8-24 keV) weakness observed by NuSTAR requires Compton-thick absorption if these objects have nominal underlying X-ray emission. However, a soft stacked effective photon index (Γ eff ≈ 1.8) for this sample disfavors Compton-thick absorption in general. The uniform hard X-ray weakness observed by NuSTAR for this and the pilot samples selected with <10 keV weakness also suggests that the X-ray weakness is intrinsic in at least some of the targets. We conclude that the NuSTAR observations have likely discovered a significant population (≳ 33%) of intrinsically X-ray weak objects among the BAL quasars with significantly weak <10 keV emission. We suggest that intrinsically X-ray weak quasars might be preferentially observed as BAL quasars.

Thomson parabola spectrometry for gold laser generated plasmas

Czech Academy of Sciences Publication Activity Database

Torrisi, L.; Cutroneo, M.; Andó, L.; Ullschmied, Jiří

2013-01-01

Roč. 20, č. 2 (2013), 023106-023106 ISSN 1070-664X R&D Projects: GA MŠk LM2010014 Institutional research plan: CEZ:AV0Z20430508 Keywords : acceleration * ions * Thomson parabola spectrometry * PALS laser * laser targets * gold ions Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 2.249, year: 2013 http://pop.aip.org/resource/1/phpaen/v20/i2/p023106_s1

TV thomson scattering system on JFT-2M