WorldWideScience

Sample records for hard x-ray phase-enhanced

  1. Microfabrication of hard x-ray lenses

    DEFF Research Database (Denmark)

    Stöhr, Frederik

    This thesis deals with the development of silicon compound refractive lenses (Si-CRLs) for shaping hard x-ray beams. The CRLs are to be fabricated using state of the art microfabrication techniques. The primary goal of the thesis work is to produce Si-CRLs with considerably increased structure...... developed. Inverse replica molding in PDMS of the CRLs was established as an effective way to circumvent the limitations AFM probes have when concave surfaces need to be characterized, e.g. due to the finite lengths of AFM probes. Four different x-ray optical components have been designed, manufactured...... of space for sample surroundings and ensure low-divergent and wide x-ray beams with narrow waists. Both results are substantial improvements to what was available at the start of this thesis work. The challenge of making x-ray objectives in silicon by interdigitation of lenslets alternately focusing...

  2. Hard X-ray Laue monochromator

    Science.gov (United States)

    Kocharyan, V. R.; Gogolev, A. S.; Kiziridi, A. A.; Batranin, A. V.; Muradyan, T. R.

    2016-06-01

    Experimental studies of X-ray diffraction from reflecting atomic planes (10¯11) of X-cut quartz single crystal in Laue geometry influenced by the temperature gradient were carried out. It is shown that by using the temperature gradient it is possible to reflect a hard X- ray beam with photon energy near the 100 keV with high efficiency. It has been experimentally proved that the intensity of the reflected beam can be increased by more than order depending on the value of the temperature gradient.

  3. Hard X-ray laue monochromator

    OpenAIRE

    Kocharian, Vagan Rashidovich; Gogolev, Aleksey Sergeevich; Kiziridi, A. A.; Batranin, Andrey Viktorovich; Muradyan, T. R.

    2016-01-01

    Experimental studies of X-ray diffraction from reflecting atomic planes (1011) of X-cut quartz single crystal in Laue geometry influenced by the temperature gradient were carried out. It is shown that by using the temperature gradient it is possible to reflect a hard Xray beam with photon energy near the 100 keV with high efficiency. It has been experimentally proved that the intensity of the reflected beam can be increased by more than order depending on the value of the temperature gradient.

  4. Hard X-ray Footpoint Source Sizes

    Science.gov (United States)

    Dennis, Brian R.; Kontar, E. P.; Gopie, A. A.; Tolbert, A. K.; Schwartz, R. A.

    2010-05-01

    RHESSI has detected compact hard (25 - 100 keV) X-ray sources that are ɜ arcseconds (FWHM) in extent for certain flares (Dennis and Pernak (2009). These sources are believed to be at magnetic loop footpoints that are known from observations at other wavelengths to be very small. Flare ribbons seen in the UV with TRACE, for example, are 1 arcsecond in width, and white light flares show structure at the 1 arcsecond level. However, Kontar and Jeffrey (2010) have shown that the measured extent should be >6 arcseconds, even if the X-ray emitting thick-target source is point-like. This is because of the strong albedo contribution in the measured energy range for a source located at the expected altitude of 1 Mm near the top of the chromosphere. This discrepancy between observations and model predictions may indicate that the source altitude is significantly lower than assumed or that the RHESSI image reconstruction procedures are not sensitive to the more diffuse albedo patch in the presence of a strong compact source. Results will be presented exploring the latter possibility using the Pixon image reconstruction procedure and other methods based on visibilities. Dennis, B. R. and Pernak, R. L., 2009, ApJ, 698, 2131-2143. Kontar, E. P. and Jeffrey, N. L. S., 2010, A&A, in press.

  5. Hard X-Ray Footprint Source Sized

    Science.gov (United States)

    Dennis, Brian R.; Kontar, E. P.

    2010-01-01

    RHESSI has detected compact hard (25 - 100 keV) X-ray sources that are Pernak (2009). These sources are believed to be at magnetic loop footpoints that are known from observations at other wavelengths to be very small. Flare ribbons seen in the W with TRACE, for example, are approx. 1 arcsecond in width, and white light flares show structure at the approx. 1 arcsecond level. However, Kontar and Jeffrey (2010) have shown that the measured extent should be >6 arcseconds, even if the X-ray emitting thick-target source is point-like. This is because of the strong albedo contribution in the measured energy range for a source located at the expected altitude of 1 Mm near the top of the chromosphere. This discrepancy between observations and model predictions may indicate that the source altitude is significantly lower than assumed or that the RHESSI image reconstruction procedures are not sensitive to the more diffuse albedo patch in the presence of a strong compact source. Results will be presented exploring the latter possibility using the Pixon image reconstruction procedure and other methods based on visibilities.

  6. Hard x-ray telescope mission

    DEFF Research Database (Denmark)

    Gorenstein, P.; Worrall, D.; Joensen, K.D.

    1996-01-01

    The Hard X-Ray Telescope was selected for study as a possible new intermediate size mission for the early 21st century. Its principal attributes are: (1) multiwavelength observing with a system of focussing telescopes that collectively observe from the UV to over 1 MeV, (2) much higher sensitivity...... and much better angular resolution in the 10 - 100 keV band, and (3) higher sensitivity for detecting gamma ray lines of known energy in the 100 keV to 1 MeV band. This paper emphasizes the mission aspects of the concept study such as the payload configuration and launch vehicle. An engineering team...... at the Marshall Space Center is participating in these two key aspects of the study....

  7. Dual Energy X-Ray CT by Compton Scattering Hard X-Ray Source

    CERN Document Server

    Uesaka, Mitsuru; Kaneyasu, Tatsuo; Torikoshi, Masami

    2005-01-01

    We have developed a compact Compton scattering hard X-ray source at Nuclear Engineering Research Laboratory, University of Tokyo. The compact hard X-ray source can produce tunable monochromatic hard X-rays. The monochromatic hard X-rays are required in large field of medical and biological applications. We are planning to perform dual-energy X-ray CT, which enables us to measure atomic number Z distribution and electron density re distribution in a material. The hard X-ray source has an advantage to perform dual-energy X-ray CT. The X-ray energy can be changed quickly by introducing a fundamental frequency and a second harmonic frequency lasers. This quick energy change is indispensable to medical imaging and very difficult in a large SR light source and others. The information on the atomic number and electron density will be used for treatment plan in radiotherapy as well as for identification of materials in a nondestructive test. We examined applicability of the dual-energy X-ray CT for atomic number meas...

  8. Subgroup report on hard x-ray microprobes

    Energy Technology Data Exchange (ETDEWEB)

    Ice, G.E. [Oak Ridge National Lab., TN (United States); Barbee, T.; Bionta, R. [Lawrence Livermore National Lab., CA (United States); Howells, M.; Thompson, A.C. [Lawrence Berkeley Lab., CA (United States); Yun, W. [Argonne National Lab., IL (United States)

    1994-09-01

    The increasing availability of synchrotron x-ray sources has stimulated the development of advanced hard x-ray (E{>=}5 keV) microprobes. New x-ray optics have been demonstrated which show promise for achieving intense submicron hard x-ray probes. These probes will be used for extraordinary elemental detection by x-ray fluorescence/absorption and for microdiffraction to identify phase and strain. The inherent elemental and crystallographic sensitivity of an x-ray microprobe and its inherently nondestructive and penetrating nature makes the development of an advanced hard x-ray microprobe an important national goal. In this workshop state-of-the-art hard x-ray microprobe optics were described and future directions were discussed. Gene Ice, Oak Ridge National Laboratory (ORNL), presented an overview of the current status of hard x-ray microprobe optics and described the use of crystal spectrometers to improve minimum detectable limits in fluorescent microprobe experiments. Al Thompson, Lawrence Berkeley Laboratory (LBL), described work at the Center for X-ray Optics to develop a hard x-ray microprobe based on Kirkpatrick-Baez (KB) optics. Al Thompson also showed the results of some experimental measurements with their KB optics. Malcolm Howells presented a method for bending elliptical mirrors and Troy Barbee commented on the use of graded d spacings to achieve highest efficiency in KB multilayer microfocusing. Richard Bionta, Lawrence Livermore National Laboratory (LLNL), described the development of the first hard x-ray zone plates and future promise of so called {open_quotes}jelly roll{close_quotes} or sputter slice zone plates. Wenbing Yun, Argonne National Laboratory (ANL), described characterization of jelly roll and lithographically produced zone plates and described the application of zone plates to focus extremely narrow bandwidths by nuclear resonance. This report summarizes the presentations of the workshop subgroup on hard x-ray microprobes.

  9. 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 (hard X-rays, making them excellent sources for time-resolved studies. Here we show that, despite the inherent instabilities of 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...

  10. Broad-band hard X-ray reflectors

    DEFF Research Database (Denmark)

    Joensen, K.D.; Gorenstein, P.; Hoghoj, P.

    1997-01-01

    Interest in optics for hard X-ray broad-band application is growing. In this paper, we compare the hard X-ray (20-100 keV) reflectivity obtained with an energy-dispersive reflectometer, of a standard commercial gold thin-film with that of a 600 bilayer W/Si X-ray supermirror. The reflectivity...... that of the gold, Various other design options are discussed, and we conclude that continued interest in the X-ray supermirror for broad-band hard X-ray applications is warranted....... of the multilayer is found to agree extraordinarily well with theory (assuming an interface roughness of 4.5 Angstrom), while the agreement for the gold film is less, The overall performance of the supermirror is superior to that of gold, extending the band of reflection at least a factor of 2.8 beyond...

  11. The hard X-ray perspective on the soft X-ray excess

    Energy Technology Data Exchange (ETDEWEB)

    Vasudevan, Ranjan V.; Mushotzky, Richard F.; Reynolds, Christopher S.; Lohfink, Anne M.; Zoghbi, Abderahmen [Department of Astronomy, University of Maryland, College Park, MD 20742-2421 (United States); Fabian, Andrew C. [Institute of Astronomy, Madingley Road, Cambridge CB3 0HA (United Kingdom); Gallo, Luigi C. [Department of Astronomy and Physics, Saint Mary' s University, 923 Robie Street, Halifax, Nova Scotia B3H 3C3 (Canada); Walton, Dominic, E-mail: ranjan@astro.umd.edu [Cahill Centre for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States)

    2014-04-10

    The X-ray spectra of many active galactic nuclei exhibit a 'soft excess' below 1 keV, whose physical origin remains unclear. Diverse models have been suggested to account for it, including ionized reflection of X-rays from the inner part of the accretion disk, ionized winds/absorbers, and Comptonization. The ionized reflection model suggests a natural link between the prominence of the soft excess and the Compton reflection hump strength above 10 keV, but it has not been clear what hard X-ray signatures, if any, are expected from the other soft X-ray candidate models. Additionally, it has not been possible up until recently to obtain high-quality simultaneous measurements of both soft and hard X-ray emission necessary to distinguish these models but upcoming joint XMM-NuSTAR programs provide precisely this opportunity. In this paper, we present an extensive analysis of simulations of XMM-NuSTAR observations, using two candidate soft excess models as inputs, to determine whether such campaigns can disambiguate between them by using hard and soft X-ray observations in tandem. The simulated spectra are fit with the simplest 'observer's model' of a blackbody and neutral reflection to characterize the strength of the soft and hard excesses. A plot of the strength of the hard excess against the soft excess strength provides a diagnostic plot which allows the soft excess production mechanism to be determined in individual sources and samples using current state-of-the-art and next generation hard X-ray enabled observatories. This approach can be straightforwardly extended to other candidate models for the soft excess.

  12. Hard X-ray imaging with microchannel plate optics

    CERN Document Server

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

    2002-01-01

    Square pore microchannel plates, with large channel aspect ratios, have been developed as part of an ESA technology research programme into efficient focusing at hard (>10 keV) X-ray energies. A planar MCP has been used to focus 50-65 keV X-rays for the first time.

  13. Adaptive Lobster-Eye Hard X-Ray Telescope Project

    Data.gov (United States)

    National Aeronautics and Space Administration — To address NASA needs for hard X-ray telescopes for starlight detection and wavefront analysis, Physical Optics Corporation (POC) proposes to develop an Adjustable...

  14. Scotch-Tape Mirror for Hard X-rays Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The project is to build a grazing incidence mirror for hard X-rays (E>20 keV) using a “scotch-tape” design, in which a thin plastic tape with a...

  15. A hard X-ray nanoprobe beamline for nanoscale microscopy.

    Science.gov (United States)

    Winarski, Robert P; Holt, Martin V; Rose, Volker; Fuesz, Peter; Carbaugh, Dean; Benson, Christa; Shu, Deming; Kline, David; Stephenson, G Brian; McNulty, Ian; Maser, Jörg

    2012-11-01

    The Hard X-ray Nanoprobe Beamline (or Nanoprobe Beamline) is an X-ray microscopy facility incorporating diffraction, fluorescence and full-field imaging capabilities designed and operated by the Center for Nanoscale Materials and the Advanced Photon Source at Sector 26 of the Advanced Photon Source at Argonne National Laboratory. This facility was constructed to probe the nanoscale structure of biological, environmental and material sciences samples. The beamline provides intense focused X-rays to the Hard X-ray Nanoprobe (or Nanoprobe) which incorporates Fresnel zone plate optics and a precision laser sensing and control system. The beamline operates over X-ray energies from 3 to 30 keV, enabling studies of most elements in the periodic table, with a particular emphasis on imaging transition metals.

  16. X-Ray Polarization Measurements with the EXIST Hard X-Ray Survey Telescope

    Science.gov (United States)

    Krawczynski, Henric; Garson, A., III; Hong, J.; Grindlay, J. E.

    2009-01-01

    The Energetic X-ray Imaging Survey Telescope (EXIST) is a proposed NASA mission for scanning the entire sky in intermediate and hard X-rays. The EXIST mission includes a wide field of view High Energy Telescope (HET) covering the 5-600 keV energy range, and an infrared telescope. The HET has the capability to measure the energy dependent X-ray polarization properties of moderately bright and bright X-ray sources. Here we report on a study of the polarization sensitivity of EXIST as a function of the integration time. Broadband X-ray polarization measurements with EXIST have the potential to make important contributions to our understanding of a number of astrophysical source types including binary black holes, accreting neutron stars, magnetars, pulsar wind nebulae, active galactic nuclei and gamma-ray bursts. EXIST observations of the X-rays from binary black holes can be used to constrain the spins of black holes. Last but not least, EXIST observations of active galactic nuclei and gamma-ray bursts can be used for extremely sensitive Lorentz Invariance tests.

  17. Hard X-ray Zone Plates Using Ultrananocrystalline Diamond Molds

    Science.gov (United States)

    Wojcik, M. J.; Joshi, V.; Sumant, A. V.; Divan, R.; Ocola, L. E.; Lu, M.; Mancini, D. C.

    2011-09-01

    While hard x-ray zone plates have made great advances recently towards improved resolution, their focusing efficiency requires further development. This problem becomes more important as higher-energy x-rays are used for x-ray microscopy. The current method for fabricating zone plates involves a dielectric mold, which is then electroplated into, but the materials used for this mold are not mechanically stiff enough for the zone plates desired. Ultrananocrystalline diamond (UNCD) is a form of diamond that can be grown as a thin film by chemical vapor deposition and offers many of the physical properties of bulk diamond. Its mechanical stiffness, resistance to radiation damage, dielectric properties, and ability to be etched suggests UNCD as a capable mold material. Reported is progress in the fabrication of hard x-ray zone plates with gold electroformed into a UNCD mold.

  18. Prospects for supermirrors in hard x-ray spectroscopy

    DEFF Research Database (Denmark)

    Joensen, Karsten D.; Gorenstein, Paul; Christensen, Finn Erland

    1994-01-01

    reflectivity for x rays. For hard x rays (≥ 15 keV), the absorption, however, is low enough that it is possible to design supermirrors with 10 - 70% reflectivity in a band ≈ 3 times the width of the total reflection regime. Supermirrors of W/Si and Ni/C have been successfully fabricated and characterized...... radiation, and particle filtering in plasma diagnostics....

  19. High-resolution x-ray characterization of mosaic crystals for hard x-ray astronomy

    Science.gov (United States)

    Ferrari, Claudio; Buffagni, Elisa; Marchini, Laura; Zappettini, Andrea

    2012-04-01

    GaAs, Cu, CdTe, and CdZnTe crystals have been studied as optical elements for lenses for hard x-ray astronomy. High-resolution x-ray diffraction at 8 keV in Bragg geometry and at synchrotron at energies up to 500 keV in Laue geometry has been used. A good agreement was found between the mosaicity evaluated in Bragg geometry at 8 keV with x-ray penetration of the order of few tens of micrometers and that derived at synchrotron in transmission Laue geometry at higher x-ray energies. Mosaicity values in a range between a few to 150 arcsec were found in all the samples but, due to the presence of crystal grains in the cm range, CdTe and CdZnTe crystals were found not suitable. Cu crystals exhibit a mosaicity of the order of several arcmin; they indeed were found to be severely affected by cutting damage which could only be removed with a very deep etching. The full width at half maximum of the diffraction peaks decreased at higher x-ray energies showing that the peak broadening is affected by crystallite size. GaAs crystals grown by Czochralski method showed a mosaic spread up to 30 arcsec and good diffraction efficiency up to energies of 500 keV. The use of thermal treatments as a possible method to increase the mosaic spread was also evaluated.

  20. A hard X-ray laboratory for monochromator characterisation

    Energy Technology Data Exchange (ETDEWEB)

    Hamelin, B. [Institut Max von Laue - Paul Langevin (ILL), 38 - Grenoble (France)

    1997-04-01

    Since their installation at ILL during the 1970`s the ILL {gamma}-ray diffractometers have been intensively used in the development of neutron monochromators. However, the ageing of the sources and new developments in hard X-ray diffractometry lead to a decision at the end of 1995 to replace the existing {gamma}-ray laboratory with a hard X-ray laboratory, based on a 420 keV generator, making available in the long term several beam-lines for rapid characterisation of monochromator crystals. The facility is now installed and its characteristics and advantages are outlined. (author). 2 refs.

  1. Hard X-ray imaging for landslide research.

    Science.gov (United States)

    Weon, B M; Je, J H; Gremaud, G

    2010-11-01

    Synchrotron phase-contrast hard X-ray imaging is used to provide highly efficient direct visualization of landslide dynamics and granular flows in fully wet granular piles. High penetration capability and phase-contrast enhancement of hard X-rays offer marked advantages in the precise tracking of individual granular movements through a thick water medium. It is revealed that the stress accumulation follows a power-law evolution while the relaxation follows an exponential one. The onset of landslide emerges at the trade-off of the two evolutions.

  2. AGN Science With The EXIST Hard X-ray Satellite

    Science.gov (United States)

    Coppi, Paolo S.; EXIST AGN Science Working Group

    2009-01-01

    With its large collection area, broad-band energy coverage from 10 to 600 keV, and all-sky monitoring capability, the proposed EXIST hard X-ray satellite mission will provide an unrivaled census of transient AGN activity in the nearby( zEXIST AGN hard X-ray survey coupled with a follow-up survey using the on-board optical/near-infrared telescope (IRT) will significantly advance our understanding of AGN physics and of how the AGN phenomenon fits into the overall process of galaxy formation.

  3. Observational Aspects of Hard X-ray Polarimetry

    Science.gov (United States)

    Chattopadhyay, Tanmoy

    2016-04-01

    Sensitive polarization measurements in X-ray may address a wealth of astrophysical phenomena, which so far remain beyond our understanding through available X-ray spectroscopic, imaging, and timing studies. Though scientific potential of X-ray polarimetry was realized long ago, there has not been any significant advancement in this field for the last four decades since the birth of X-ray astronomy. The only successful polarization measurement in X-rays dates back to 1976, when a Bragg polarimeter onboard OSO-8 measured polarization of Crab nebula. Primary reason behind the lack in progress is its extreme photon hungry nature, which results in poor sensitivity of the polarimeters. Recently, in the last decade or so, with the advancement in detection technology, X-ray polarimetry may see a significant progress in near future, especially in soft X-rays with the invention of photoelectron tracking polarimeters. Though photoelectric polarimeters are expected to provide sensitive polarization measurements of celestial X-ray sources, they are sensitive only in soft X-rays, where the radiation from the sources is dominated by thermal radiation and therefore expected to be less polarized. On the other hand, in hard X-rays, sources are ex-pected to be highly polarized due to the dominance of nonthermal emission over its thermal counterpart. Moreover, polarization measurements in hard X-rays promises to address few interesting scientific issues regarding geometry of corona for black hole sources, emission mechanism responsible for the higher energy peak in the blazars, accretion geometry close to the magnetic poles in accreting neutron star systems and acceleration mechanism in solar flares. Compton polarimeters provide better sensitivity than photoelectric polarimeters in hard X-rays with a broad energy band of operation. Recently, with the development of hard X-ray focusing optics e.g. NuSTAR, Astro-H, it is now possible to conceive Compton polarimeters at the focal plane

  4. Hard x-ray imaging polarimeter for PolariS

    Science.gov (United States)

    Hayashida, Kiyoshi; Kim, Juyong; Sadamoto, Masaaki; Yoshinaga, Keigo; Gunji, Shuichi; Mihara, Tatehiro; Kishimoto, Yuji; Kubo, Hidetoshi; Mizuno, Tsunefumi; Takahashi, Hiromitsu; Dotani, Tadayasu; Yonetoku, Daisuke; Nakamori, Takeshi; Yoneyama, Tomokage; Ikeyama, Yuki; Kamitsukasa, Fumiyoshi

    2016-07-01

    Hard X-ray imaging polarimeters are developed for the X-ray γ-ray polaeimtery satellite PolariS. The imaging polarimter is scattering type, in which anisotropy in the direction of Compton scattering is employed to measure the hard X-ray (10-80 keV) polarization, and is installed on the focal planes of hard X-ray telescopes. We have updated the design of the model so as to cover larger solid angles of scattering direction. We also examine the event selection algorithm to optimize the detection efficiency of recoiled electrons in plastic scintillators. We succeed in improving the efficiency by factor of about 3-4 from the previous algorithm and criteria for 18-30 keV incidence. For 23 keV X-ray incidence, the recoiled electron energy is about 1 keV. We measured the efficiency to detect recoiled electrons in this case, and found about half of the theoretical limit. The improvement in this efficiency directly leads to that in the detection efficiency. In other words, however, there is still a room for improvement. We examine various process in the detector, and estimate the major loss is primarily that of scintillation light in a plastic scintillator pillar with a very small cross section (2.68mm squared) and a long length (40mm). Nevertheless, the current model provides the MDP of 6% for 10mCrab sources, which are the targets of PolariS.

  5. Hard X-ray Microscopy with Multilayer Laue Lenses

    Science.gov (United States)

    Kang, Hyon Chol

    2011-03-01

    The possibility of imaging at near-atomic resolution using x-rays has been a dream ever since the short-wavelength nature of x-rays was demonstrated by von Laue and coworkers nearly a century ago. Even today the scientific impact of atomic-scale focusing of electromagnetic radiation would be deep and broad, because x-ray microscopy provides capabilities (ability to penetrate, sensitive and accurate elemental and structural information) that are complementary to other high-resolution microscopies. Although hard x-rays can in principle be focused to spot sizes on the order of their wavelength (0.1 nm), this limit has never been approached because of the difficulty in fabricating the optics. Multilayer Laue lens(MLL) is a novel diffractive optic for hard x-ray nano-focusing, which can be fabricated by sputter deposition of zone plate structure on flat substrate. According to the theoretical results, MLL is capable of focusing x-rays to well below 1 nm. We have demonstrated 2-dimensional focusing of hard x-rays with MLLs to a spot size of 25 nm x 27 nm with an efficiency of 2% at a photon energy of 12 keV, while 1-dimensional focus of 16 nm has been achieved. In this talk, we will present an overview of MLL microscopy and recent accomplishments for the determination of chemical composition in nanoscale systems. Lastly, we will give the capabilities of MLL microscopy that have the potential to significantly advance materials science, nanoscience, bio-medical science and environmental science.

  6. Imaging of reconnection processes in hard X-rays

    NARCIS (Netherlands)

    Svestka, Z.; Poletto, G.

    1984-01-01

    The Hard X-ray Spectrometer aboard the SMM detected several events of energy release late in the development of two-ribbon flares. One such event, at 21:12 UT on 21 May, 1980 ( 20 min after the flare onset and 15 min after the peak of the impulsive phase) is studied in detail. The site of new

  7. Crab Nebula Variations in Hard X-rays

    Science.gov (United States)

    Wilson-Hodge, Colleen A.

    2012-01-01

    The Crab Nebula was surprisingly variable from 2001-2010, with less variability before 2001 and since mid-2010. We presented evidence for spectral softening from RXTE, Swift/BAT, and Fermi GBM during the mid-2008-2010 flux decline. We see no clear connections between the hard X-ray variations and the GeV flares

  8. Hard X-ray mirrors for Nuclear Security

    Energy Technology Data Exchange (ETDEWEB)

    Descalle, M. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Brejnholt, N. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hill, R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Decker, T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Alameda, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Soufli, R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Pivovaroff, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Pardini, T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-01-07

    Research performed under this LDRD aimed to demonstrate the ability to detect and measure hard X-ray emissions using multilayer X-ray reflective optics above 400 keV, to enable the development of inexpensive and high-accuracy mirror substrates, and to investigate applications of hard X-ray mirrors of interest to the nuclear security community. Experiments conducted at the European Synchrotron Radiation Facility demonstrated hard X-ray mirror reflectivity up to 650 keV for the first time. Hard X-ray optics substrates must have surface roughness under 3 to 4 Angstrom rms, and three materials were evaluated as potential substrates: polycarbonates, thin Schott glass and a new type of flexible glass called Willow Glass®. Chemical smoothing and thermal heating of the surface of polycarbonate samples, which are inexpensive but have poor intrinsic surface characteristics, did not yield acceptable surface roughness. D263 Schott glass was used for the focusing optics of the NASA NuSTAR telescope. The required specialized hardware and process were costly and motivated experiments with a modified non-contact slumping technique. The surface roughness of the glass was preserved and the process yielded cylindrical shells with good net shape pointing to the potential advantage of this technique. Finally, measured surface roughness of 200 and 130 μm thick Willow Glass sheets was between 2 and 2.5 A rms. Additional results of flexibility tests and multilayer deposition campaigns indicated it is a promising substrate for hard X-ray optics. The detection of U and Pu characteristics X-ray lines and gamma emission lines in a high background environment was identified as an area for which X-ray mirrors could have an impact and where focusing optics could help reduce signal to noise ratio by focusing signal onto a smaller detector. Hence the first one twelvetant of a Wolter I focusing optics for the 90 to 140 keV energy range based on aperiodic multilayer coating was designed. Finally

  9. HXMT satellite for space hard X-ray observation

    Science.gov (United States)

    Wu, Y.; Ren, D.; You, Z.

    Space hard X-ray in the energy band from 10Kev to 250KeV is very important to the research of high energy astrophysical processes, especially some of the fundamental problems in astrophysics. Due to imaging difficulty in the hard X-ray band, Observations made over this band is comparatively less than other bands such as soft X-ray and gamma -ray. Up to now, there has been no hard X ray all sky- survey of high sensitivity. Based on the Direct Demodulation imaging method recently developed, the Hard X- ray Modulation Telescope(HXMT) mission is proposed under the Major State Basic Research Development Program of China. The scientific objective of HXMT mission is to realize the first hard X-ray all sky survey of high sensitivy and angular resolution in the world, and to present the first detailed sky map of hard X r a y - distribution. In this article, the physical basis, the imaging principle and the basic structure of HXMT are briefly introduced. The expected angular resolution of observation and position accuracy of radiant source are 2' and 0.2' respectively. Based on the analysis of the mission requirement of HXMT, the mission design of HXMT satellite is presented in which the concept of integrative design approach is presented and implemented. The design of spacecraft subsystems such as strcuture,C&DH and energy are also introduced. To meet the high precision demand of the attitude determination of HXMT, a new Attitude Determination &Control Subsystem(ADCS) scheme is presented in which the Microminiature Inertial Measurement Unit(MIMU) is employed as one of the key attitude sensors. Combined with star tracker, the expected attitude measurement accuracy is 0.01° in the normal mission mode. Based on all these thoughts, the ADCS is analyzed and its general design is presented in the paper. As the first chinese space hard X-ray observatory, the design approach of HXMT satellite is also helpful for other space exploration missions such as solar activity inspection

  10. Hard X-ray Sources for the Mexican Synchrotron Project

    Science.gov (United States)

    Reyes-Herrera, Juan

    2016-10-01

    One of the principal tasks for the design of the Mexican synchrotron was to define the storage ring energy. The main criteria for choosing the energy come from studying the electromagnetic spectrum that can be obtained from the synchrotron, because the energy range of the spectrum that can be obtained will determine the applications available to the users of the future light source. Since there is a public demand of hard X-rays for the experiments in the synchrotron community users from Mexico, in this work we studied the emission spectra from some hard X-ray sources which could be the best options for the parameters of the present Mexican synchrotron design. The calculations of the flux and the brightness for one Bending Magnet and four Insertion Devices are presented; specifically, for a Superconducting Bending Magnet (SBM), a Superconducting Wiggler (SCW), an In Vacuum Short Period Undulator (IV-SPU), a Superconducting Undulator (SCU) and for a Cryogenic Permanent Magnet Undulator (CPMU). Two commonly available synchrotron radiation programs were used for the computation (XOP and SRW). From the results, it can be concluded that the particle beam energy from the current design is enough to have one or more sources of hard X-rays. Furthermore, a wide range of hard X-ray region can be covered by the analyzed sources, and the choice of each type should be based on the specific characteristics of the X-ray beam to perform the experiments at the involved beamline. This work was done within the project Fomix Conacyt-Morelos ”Plan Estrategico para la construccion y operación de un Sincrotron en Morelos” (224392).

  11. Hard X-ray Imaging Polarimeter for PolariS

    Science.gov (United States)

    Hayashida, Kiyoshi

    2016-07-01

    We present the current status of development of hard X-ray imaging polarimeters for the small satellite mission PolariS. The primary aim of PolariS is hard X-ray (10-80keV) polarimetry of sources brighter than 10mCrab. Its targets include stellar black holes, neutron stars, super nova remnants, and active galactic nuclei. This aim is enabled with three sets of hard X-ray telescopes and imaging polarimeters installed on their focal planes. The imaging polarimeter consists of two kinds of (plastic and GSO) scintillator pillars and multi-anode photo multiplier tubes (MAPMTs). When an X-ray photon incident to a plastic scintillator cause a Compton scattering, a recoiled electron makes a signal on the corresponding MAPMT pixel, and a scatted X-rays absorbed in surrounding GSO makes another signal. This provide information on the incident position and the scattered direction. The latter information is employed for polarimetry. For 20keV X-ray incidence, the recoiled electron energy is as low as 1keV. Thus, the performance of this imaging polarimeter is primarily determined by the efficiency that we can detect low level signal of recoiled electrons generated in plastic scintillators. The efficiency could depend on multiple factors, e.g. quenching of light in scintillators, electric noise, pedestal error, cross talk of the lights to adjacent MAPMT pixels, MAPMT dark current etc. In this paper, we examined these process experimentally and optimize the event selection algorithm, in which single photo-electron events are selected. We then performed an X-ray (10-80keV monochromatic polarized beam) irradiation test at a synchrotron facility. The modulation contrast (M) is about 60% in 15-80keV range. We succeeded in detecting recoiled electrons for 10-80keV X-ray incidence, though detection efficiency is lower at lowest end of the energy range. Expected MDP will also be shown.

  12. The Correlation between Hard X-Ray Peak Flux and Soft X-Ray Peak Flux in the Outburst Rise of Low-Mass X-Ray Binaries

    NARCIS (Netherlands)

    Yu, W.; van der Klis, M.; Fender, R.P.

    2004-01-01

    We have analyzed Rossi X-Ray Timing Explorer pointed observations of the outbursts of black hole and neutron star soft X-ray transients in which an initial low/hard state, or ``island'' state, followed by a transition to a softer state was observed. In three sources-the black hole transient XTE

  13. A new hard X-ray transient discovered by INTEGRAL

    DEFF Research Database (Denmark)

    Gibaud, L.; Bazzano, A.; Bozzo, E.

    2011-01-01

    INTEGRAL discovered a new hard X-ray transient, IGR J17498-2921, during the observations performed from 2011-08-11 22:45 to 2011-08-12 05:54 UTC. The source is detected in the IBIS/ISGRI mosaic at a preliminary significance level of 11 and 9 sigma in the 20-40 keV and 40-80 keV energy bands, resp...

  14. Bulk sensitive hard x-ray photoemission electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Patt, M., E-mail: m.patt@fz-juelich.de; Wiemann, C. [Peter Grünberg Institute (PGI-6) and JARA-FIT, Research Center Jülich, D-52425 Jülich (Germany); Weber, N.; Escher, M.; Merkel, M. [Focus GmbH, Neukirchner Str. 2, D-65510 Hünstetten (Germany); Gloskovskii, A.; Drube, W. [DESY Photon Science, Deutsches Elektronen-Synchrotron, D-22603 Hamburg (Germany); Schneider, C. M. [Peter Grünberg Institute (PGI-6) and JARA-FIT, Research Center Jülich, D-52425 Jülich (Germany); Fakultät f. Physik and Center for Nanointegration Duisburg-Essen (CeNIDE), Universität Duisburg-Essen, D-47048 Duisburg (Germany)

    2014-11-15

    Hard x-ray photoelectron spectroscopy (HAXPES) has now matured into a well-established technique as a bulk sensitive probe of the electronic structure due to the larger escape depth of the highly energetic electrons. In order to enable HAXPES studies with high lateral resolution, we have set up a dedicated energy-filtered hard x-ray photoemission electron microscope (HAXPEEM) working with electron kinetic energies up to 10 keV. It is based on the NanoESCA design and also preserves the performance of the instrument in the low and medium energy range. In this way, spectromicroscopy can be performed from threshold to hard x-ray photoemission. The high potential of the HAXPEEM approach for the investigation of buried layers and structures has been shown already on a layered and structured SrTiO{sub 3} sample. Here, we present results of experiments with test structures to elaborate the imaging and spectroscopic performance of the instrument and show the capabilities of the method to image bulk properties. Additionally, we introduce a method to determine the effective attenuation length of photoelectrons in a direct photoemission experiment.

  15. Hard X-rays in–soft X-rays out: An operando piggyback view deep into a charging lithium ion battery with X-ray Raman spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Braun, Artur, E-mail: artur.braun@alumni.ethz.ch [Laboratory for High Performance Ceramics. Empa, Swiss Federal Laboratories for Materials Science and Technology, CH-8600 Dübendorf (Switzerland); Nordlund, Dennis [Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94720 (United States); Song, Seung-Wan [Department of Fine Chemical Engineering & Applied Chemistry, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Huang, Tzu-Wen [Laboratory for High Performance Ceramics. Empa, Swiss Federal Laboratories for Materials Science and Technology, CH-8600 Dübendorf (Switzerland); Sokaras, Dimosthenis [Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94720 (United States); Liu, Xiasong; Yang, Wanli [Advanced Light Source, Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Weng, Tsu-Chien [Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94720 (United States); Liu, Zhi [Advanced Light Source, Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

    2015-04-15

    Graphical abstract: - Abstract: For lithium intercalation battery electrodes, understanding of the electronic structure of bulk and surface is essential for their operation and functionality. Soft X-rays are excellent probes for such electronic structure information, but soft X-rays are predominantly surface sensitive and thus cannot probe the bulk. Moreover, soft X-rays hardly permit meaningful in situ and operando studies in battery assemblies. We show here how we penetrate with hard X-rays (>10 keV) in situ a lithium cell, containing a manganite-based cathode. Through X-ray Raman spectroscopy we extract the Mn 2p multiplet from the entire cathode material, thus obtaining bulk-sensitive electronic structure information during battery charging and discharging.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2004-07-01

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

  17. Hard X-rays from hybrid X pinches

    Energy Technology Data Exchange (ETDEWEB)

    Shelkovenko, T. A., E-mail: tc50@cornell.edu; Pikuz, S. A., E-mail: tc50@cornell.edu [Cornell University, Ithaca, New York, 14853, USA and P. N. Lebedev Institute, 53 Leninskii Prospect, Moscow, 119991 (Russian Federation); Hoyt, C. L.; Cahill, A. D.; Hammer, D. A. [Cornell University, Ithaca, New York, 14853 (United States); Tilikin, I. N.; Mingaleev, A. R.; Agafonov, A. V. [P. N. Lebedev Institute, 53 Leninskii Prospect, Moscow, 119991 (Russian Federation)

    2014-12-15

    X pinches are well known to produce very small, dense plasma pinches (“hot spots”) that emit short bursts of 1.5–8 keV radiation. Hard X-ray radiation in the 8–100 keV range is also emitted, only a small portion of which is associated with the X-pinch hot spot. In hybrid X-pinches, the “long” X-ray pulse is terminated by fast closure of the gap between the two conical electrodes by rapidly expanding electrode plasmas. The temporal, spectral, and spatial properties of this higher energy radiation, 10 – 60 keV, have been studied. This radiation was used for point-projection imaging with magnification between 1.5 and 3, and spatial resolution less than100 micrometers was demonstrated.

  18. Deducing Electron Properties from Hard X-Ray Observations

    Science.gov (United States)

    Kontar, E. P.; Brown, J. C.; Emslie, A. G.; Hajdas, W.; Holman, G. D.; Hurford, G. J.; Kasparova, J.; Mallik, P. C. V.; Massone, A. M.; McConnell, M. L.; hide

    2011-01-01

    X-radiation from energetic electrons is the prime diagnostic of flare-accelerated electrons. The observed X-ray flux (and polarization state) is fundamentally a convolution of the cross-section for the hard X-ray emission process(es) in question with the electron distribution function, which is in turn a function of energy, direction, spatial location and time. To address the problems of particle propagation and acceleration one needs to infer as much information as possible on this electron distribution function, through a deconvolution of this fundamental relationship. This review presents recent progress toward this goal using spectroscopic, imaging and polarization measurements, primarily from the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI). Previous conclusions regarding the energy, angular (pitch angle) and spatial distributions of energetic electrons in solar flares are critically reviewed. We discuss the role and the observational evidence of several radiation processes: free-free electron-ion, free-free electron-electron, free-bound electron-ion, photoelectric absorption and Compton backscatter (albedo), using both spectroscopic and imaging techniques. This unprecedented quality of data allows for the first time inference of the angular distributions of the X-ray-emitting electrons and improved model-independent inference of electron energy spectra and emission measures of thermal plasma. Moreover, imaging spectroscopy has revealed hitherto unknown details of solar flare morphology and detailed spectroscopy of coronal, footpoint and extended sources in flaring regions. Additional attempts to measure hard X-ray polarization were not sufficient to put constraints on the degree of anisotropy of electrons, but point to the importance of obtaining good quality polarization data in the future.

  19. Hard-X-ray Zone Plates: Recent Progress

    Directory of Open Access Journals (Sweden)

    Syue-Ren Wu

    2012-09-01

    Full Text Available The technology to focus hard-X-rays (photon energy larger than 1–2 keV has made great progress in the past three years. The progress was particularly spectacular for lenses based on the Fresnel zone plate concept. The spatial resolution notably increased by a factor of three, opening up entirely new domains of application, specifically in biomedical research. As we shall see, this evolution is the result of a painstaking optimization of many different aspects rather than of a single technical breakthrough.

  20. NuSTAR Hard X-ray Optics

    DEFF Research Database (Denmark)

    Koglin, Jason E.; Christensen, Finn Erland; Craig, William W.

    2005-01-01

    The Nuclear Spectroscopic Telescope Array (NuSTAR) is a small explorer (SMEX) mission currently under an extended Phase A study by NASA. NuSTAR will be the first satellite mission to employ focusing optics in the hard X-ray band (8- 80 keV). Its design eliminates high detector backgrounds, allows...... and production process. We also describe the progress of several components of our independent optics development program that are beginning to reach maturity and could possibly be incorporated into the NuSTAR production scheme. We then present environmental test results that are being conducted in preparation...... of full space qualification of the NuSTAR optics....

  1. NuSTAR Hard X-Ray Survey of the Galactic Center Region. II. X-Ray Point Sources

    DEFF Research Database (Denmark)

    Hong, JaeSub; Mori, Kaya; Hailey, Charles J.

    2016-01-01

    We present the first survey results of hard X-ray point sources in the Galactic Center (GC) region by NuSTAR. We have discovered 70 hard (3-79 keV) X-ray point sources in a 0.6 deg2 region around Sgr A* with a total exposure of 1.7 Ms, and 7 sources in the Sgr B2 field with 300 ks. We identify...... persistent luminous X-ray binaries (XBs) and the likely run-away pulsar called the Cannonball. New source-detection significance maps reveal a cluster of hard (>10 keV) X-ray sources near the Sgr. A diffuse complex with no clear soft X-ray counterparts. The severe extinction observed in the Chandra spectra...... indicate that the X-ray spectra of the NuSTAR sources should have kT > 20 keV on average for a single temperature thermal plasma model or an average photon index of Gamma = 1.5-2 for a power-law model. These findings suggest that the GC X-ray source population may contain a larger fraction of XBs with high...

  2. Backscatter of hard X-rays in the solar atmosphere. [Calculating the reflectance of solar x ray emission

    Science.gov (United States)

    Bai, T.; Ramaty, R.

    1977-01-01

    The solar photosphere backscatters a substantial fraction of the hard X rays from solar flares incident upon it. This reflection was studied using a Monte Carlo simulation which takes into account Compton scattering and photo-electric absorption. Both isotropic and anisotropic X ray sources are considered. The bremsstrahlung from an anisotropic distribution of electrons are evaluated. By taking the reflection into account, the inconsistency is removed between recent observational data regarding the center-to-limb variation of solar X ray emission and the predictions of models in which accelerated electrons are moving down toward the photosphere.

  3. Pulse pile-up in hard X-ray detector systems. [for solar X-rays

    Science.gov (United States)

    Datlowe, D. W.

    1975-01-01

    When pulse-height spectra are measured by a nuclear detection system at high counting rates, the probability that two or more pulses will arrive within the resolving time of the system is significant. This phenomenon, pulse pile-up, distorts the pulse-height spectrum and must be considered in the interpretation of spectra taken at high counting rates. A computational technique for the simulation of pile-up is developed. The model is examined in the three regimes where (1) the time between pulses is long compared to the detector-system resolving time, (2) the time between pulses is comparable to the resolving time, and (3) many pulses occur within the resolving time. The technique is used to model the solar hard X-ray experiment on the OSO-7 satellite; comparison of the model with data taken during three large flares shows excellent agreement. The paper also describes rule-of-thumb tests for pile-up and identifies the important detector design factors for minimizing pile-up, i.e., thick entrance windows and short resolving times in the system electronics.

  4. High spatial resolution hard X-ray microscope using X-ray refractive lens and phase contrast imaging experiments

    CERN Document Server

    Kohmura, Y; Takeuchi, A; Takano, H; Suzuki, Y; Ishikawa, T; Ohigashi, T; Yokosuka, H

    2001-01-01

    A high spatial resolution X-ray microscope was constructed using an X-ray refractive lens as an objective. The spatial resolution was tested using 18 keV X-ray. A 0.4 mu m line and 0.4 mu m space tantalum test pattern was successfully resolved. Using the similar setup with the addition of a phase plate, a Zernike type phase-contrast microscopy experiment was carried out for the phase retrieval of the samples. Two-dimensional phase-contrast images were successfully taken for the first time in the hard X-ray region. Images of a gold mesh sample were analyzed and the validity of this method was indicated. An improvement of the lens, however, is required for the precise phase retrieval of the samples.

  5. Fermi GBM detection of a rise in Hard X-rays from Cyg X-1

    Science.gov (United States)

    Wilson-Hodge, C. A.; Case, G.; Cherry, M.; Rodi, J.; Jenke, P.; Finger, M.

    2014-05-01

    Fermi GBM data show an increase in hard X-rays consistent with the transition to the hard state reported by MAXI (ATel #6115). Recently, Fermi GBM observations using the Earth occultation technique show an increase in the hard X-ray flux, beginning about February 28 (MJD 56716). ...

  6. Multilayer on-chip stacked Fresnel zone plates: Hard x-ray fabrication and soft x-ray simulations

    Energy Technology Data Exchange (ETDEWEB)

    Li, Kenan; Wojcik, Michael J.; Ocola, Leonidas E.; Divan, Ralu; Jacobsen, Chris

    2015-11-01

    Fresnel zone plates are widely used as x-ray nanofocusing optics. To achieve high spatial resolution combined with good focusing efficiency, high aspect ratio nanolithography is required, and one way to achieve that is through multiple e-beam lithography writing steps to achieve on-chip stacking. A two-step writing process producing 50 nm finest zone width at a zone thickness of 1.14 µm for possible hard x-ray applications is shown here. The authors also consider in simulations the case of soft x-ray focusing where the zone thickness might exceed the depth of focus. In this case, the authors compare on-chip stacking with, and without, adjustment of zone positions and show that the offset zones lead to improved focusing efficiency. The simulations were carried out using a multislice propagation method employing Hankel transforms.

  7. Experimental study on hard X-ray generation of relativistic electron beams in azimuthal magnetic field

    CERN Document Server

    Fan Ya Jun; Qiu Aici

    2002-01-01

    Experimental study on hard X-ray generation was carried out on Flash 2 accelerator, with the method of relativistic electron beams transported in a low pressure gas via azimuthal magnetic field and interacted with Ta target. At 47 cm transporting distance, the measured areal integral of hard X-ray dose rate was 2.1 x 10 sup 1 sup 0 Gy centre dot cm sup 2 /s, total areal integral of hard X-ray dose was 1843 Gy centre dot cm sup 2 , and X-ray convert rate was 108 Gy centre dot cm sup 2 /kJ

  8. Status report of the hard x-ray detector

    Science.gov (United States)

    Yamada, Shin'ya; HXD Team

    2012-03-01

    The current status and the improvements of in-orbit calibration in the Hard X-ray Detector (HXD) on board Suzaku are presented. We have been extensively monitoring and calibrating the in-orbit HXD performance, and succeeded in keeping all the sensors working property without any significant troubles since the launch. To reduce the increasing thermal noise events due to radiation damage in the HXD-PIN, we have raised the analog/digital threshold levels and updated the corresponding responses of the PIN. Performing the calibration of the energy scale of the GSO, we have improved the accuracy of the energy scale and modeling of gain variations, and released the reprocessed data/background and the responses since April of 2010. These revised data of the GSO is usable down to 50 keV, consequently allowing us to utilize overlapping energy ranges of 50-70 keV between the PIN and the GSO. Based on these improvements, we have reproduced the HXD spectra of the Crab Nebula over 10-500 keV with the broken power law with a cutoff at about 120 keV.

  9. Probing buried layers by photoelectron spectromicroscopy with hard x-ray excitation

    Energy Technology Data Exchange (ETDEWEB)

    Wiemann, C.; Patt, M.; Cramm, S. [Peter Gruenberg Institute (PGI-6) and JARA-FIT, Research Centre Juelich, D-52425 Juelich (Germany); Escher, M.; Merkel, M. [FOCUS GmbH, D-65510 Huenstetten (Germany); Gloskovskii, A. [Institut fuer Anorganische Chemie und Analytische Chemie, Johannes Gutenberg-Universitaet Mainz, D-55128 Mainz (Germany); Thiess, S.; Drube, W. [DESY Photon Science, Deutsches Elektronen-Synchrotron, D-22603 Hamburg (Germany); Schneider, C. M. [Peter Gruenberg Institute (PGI-6) and JARA-FIT, Research Centre Juelich, D-52425 Juelich (Germany); Fakultaet f. Physik and Center for Nanointegration Duisburg-Essen (CENIDE), Universitaet Duisburg-Essen, D-47048 Duisburg (Germany)

    2012-05-28

    We report about a proof-of-principle experiment which explores the perspectives of performing hard x-ray photoemission spectromicroscopy with high lateral resolution. Our results obtained with an energy-filtered photoemission microscope at the PETRA III storage ring facility using hard x-ray excitation up to 6.5 keV photon energy demonstrate that it is possible to obtain selected-area x-ray photoemission spectra from regions less than 500 nm in diameter.

  10. Hard X-ray Emission along the Z Track in GX 17+ 2

    Indian Academy of Sciences (India)

    -ray Timing Experiment (HEXTE) on board Rossi X-Ray Timing Explorer for Z source GX 17+2, we investigate the evolution of its PCA spectra and HEXTE spectra along a `Z' track on its hardness-intensity diagram. A hard X-ray tail is detected ...

  11. Extended hard-X-ray emission in the inner few parsecs of the Galaxy

    DEFF Research Database (Denmark)

    Perez, Kerstin; Hailey, Charles J.; Bauer, Franz E.

    2015-01-01

    of objects emitting soft X-rays (less than 10 kiloelectronvolts) within the surrounding hundreds of parsecs, as well as the population responsible for unresolved X-ray emission extending along the Galactic plane, is dominated by accreting white dwarf systems. Observations of diffuse hard-X-ray (more than 10...... range. This emission is more sharply peaked towards the Galactic Centre than is the surface brightness of the soft-X-ray population. This could indicate a significantly more massive population of accreting white dwarfs, large populations of low-mass X-ray binaries or millisecond pulsars, or particle...

  12. Generation of hard X-rays by irradiation of femtosecond terawatt laser

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Kazutaka G.; Hironaka, Yoichiro; Saito, Fumikazu; Kondo, Ken-ichi [Materials and Structures Laboratory, Tokyo Institute of Technology, Yokohama, Kanagawa (Japan)

    2000-03-01

    Ultra-short pulsed hard X-rays are generated by focusing femtosecond laser beams onto metal targets with a table-top-terawatt system. Temporal and energy profiles of the generated X-rays are measured with an X-ray streak camera and an X-ray CCD camera, respectively. X-rays with a pulse width of 6 ps and an energy of 8 keV are generated from a copper target with a power density of 10{sup 17} W/cm{sup 2}. (author)

  13. Detectability of rotation-powered pulsars in future hard X-ray surveys

    Science.gov (United States)

    Wang, Wei

    2009-11-01

    Recent INTEGRAL/IBIS hard X-ray surveys have detected about 10 young pulsars. We show hard X-ray properties of these 10 young pulsars, which have a luminosity of 1033-1037 erg s-1 and a photon index of 1.6-2.1 in the energy range of 20-100 keV. The correlation between X-ray luminosity and spin-down power of LX propto Lsd1.31suggests that the hard X-ray emission in rotation-powered pulsars is dominated by the pulsar wind nebula (PWN) component. Assuming spectral properties are similar in 20-100 keV and 2-10 keV for both the pulsar and PWN components, the hard X-ray luminosity and flux of 39 known young X-ray pulsars and 8 millisecond pulsars are obtained, and a correlation of LX propto Lsd1.5 is derived. About 20 known young X-ray pulsars and 1 millisecond pulsars could be detected with future INTEGRAL and HXMT surveys. We also carry out Monte Carlo simulations of hard X-ray pulsars in the Galaxy and the Gould Belt, assuming values for the pulsar birth rate, initial position, proper motion velocity, period, and magnetic field distribution and evolution based on observational statistics and the LX - Lsd relations: LX propto Lsd1.31 and LX propto Lsd1.5. More than 40 young pulsars (mostly in the Galactic plane) could be detected after ten years of INTEGRAL surveys and the launch of HXMT. So, the young pulsars would be a significant part of the hard X-ray source population in the sky, and will contribute to unidentified hard X-ray sources in present and future hard X-ray surveys by INTEGRAL and HXMT.

  14. Hard X-ray Optics Technology Development for Astronomy at the Marshall Space Flight Center

    Science.gov (United States)

    Gubarev, Mikhail; Ramsey, Brian; Kilaru, Kiranmayee

    2009-01-01

    Grazing-incidence telescopes based on Wolter 1 geometry have delivered impressive advances in astrophysics at soft-x-ray wavelengths, while the hard xray region remains relatively unexplored at fine angular resolution and high sensitivities. The ability to perform ground-breaking science in the hard-x-ray energy range had been the motivation for technology developments aimed at fabricating low-cost, light-weight, high-quality x-ray mirrors. Grazing-incidence x-ray optics for high-energy astrophysical applications is being developed at MSFC using the electroform-nickel replication process.

  15. Hard X-ray Vela supernova observation on rocket experiment WRX-R

    Science.gov (United States)

    Stehlikova, V.; Urban, M.; Nentvich, O.; Daniel, V.; Sieger, L.; Tutt, J.

    2017-07-01

    This paper presents a hard X-ray telescope for the Vela nebula observation during a sounding rocket flight. The Water Recovery X-ray Rocket (WRX-R) experiment is organised by the Pennsylvania State University (PSU), USA with a primary payload of a soft X-ray spectroscope. The Czech team developed a hard X-ray Lobster-eye telescope as a secondary payload. The Czech experiment’s astrophysical object of study is the Vela pulsar in the centre of the Vela nebula.

  16. Hard X-ray quantum optics in thin films nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Haber, Johann Friedrich Albert

    2017-05-15

    This thesis describes quantum optical experiments with X-rays with the aim of reaching the strong-coupling regime of light and matter. We make use of the interaction which arises between resonant matter and X-rays in specially designed thin-film nanostructures which form X-ray cavities. Here, the resonant matter are Tantalum atoms and the Iron isotope {sup 57}Fe. Both limit the number of modes available to the resonant atoms for interaction, and enhances the interaction strength. Thus we have managed to observe a number of phenomena well-known in quantum optics, which are the building blocks for sophisticated applications in e.g. metrology. Among these are the strong coupling of light and matter and the concurrent exchange of virtual photons, often called Rabi oscillations. Furthermore we have designed and tested a type of cavity hitherto unused in X-ray optics. Finally, we develop a new method for synchrotron Moessbauer spectroscopy, which not only promises to yield high-resolution spectra, but also enables the retrieval of the phase of the scattered light. The results open new avenues for quantum optical experiments with X-rays, particularly with regards to the ongoing development of high-brilliance X-ray free-electron lasers.

  17. Low-energy shelf response in thin energy-dispersive X-ray detectors from Compton scattering of hard X-rays

    Science.gov (United States)

    Michel-Hart, N.; Elam, W. T.

    2017-08-01

    Silicon drift detectors have been successfully employed in both soft and hard X-ray spectroscopy. The response function to incident radiation at soft X-ray levels has been well studied and modeled, but less research has been published on response functions for these detectors to hard X-ray input spectra above 20 keV. When used with hard X-ray sources a significant low energy, non-peak response exists which can adversely affect detection limits for lighter elements in, for example, X-ray fluorescence spectroscopy. We present a numerical model that explains the non-peak response function of silicon drift detectors to hard X-rays based on incoherent Compton scattering within the detector volume. Experimental results are presented and numerically compared to model results.

  18. NuSTAR HARD X-RAY SURVEY OF THE GALACTIC CENTER REGION. I. HARD X-RAY MORPHOLOGY AND SPECTROSCOPY OF THE DIFFUSE EMISSION

    Energy Technology Data Exchange (ETDEWEB)

    Mori, Kaya; Hailey, Charles J.; Perez, Kerstin; Nynka, Melania; Zhang, Shuo; Canipe, Alicia M. [Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); Krivonos, Roman; Tomsick, John A.; Barrière, Nicolas; Boggs, Steven E.; Craig, William W. [Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States); Hong, Jaesub [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Ponti, Gabriele [Max-Planck-Institut f. extraterrestrische Physik, HEG, Garching (Germany); Bauer, Franz [Instituto de Astrofísica, Facultad de Física, Pontificia Universidad Católica de Chile, 306, Santiago 22 (Chile); Alexander, David M. [Department of Physics, Durham University, Durham DH1 3LE (United Kingdom); Baganoff, Frederick K. [Kavli Institute for Astrophysics and Space Research, Massachusets Institute of Technology, Cambridge, MA 02139 (United States); Barret, Didier [Université de Toulouse, UPS-OMP, IRAP, Toulouse (France); Christensen, Finn E. [DTU Space—National Space Institute, Technical University of Denmark, Elektrovej 327, DK-2800 Lyngby (Denmark); Forster, Karl [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Giommi, Paolo, E-mail: kaya@astro.columbia.edu [ASI Science Data Center, Via del Politecnico snc I-00133, Roma (Italy); and others

    2015-12-01

    We present the first sub-arcminute images of the Galactic Center above 10 keV, obtained with NuSTAR. NuSTAR resolves the hard X-ray source IGR J17456–2901 into non-thermal X-ray filaments, molecular clouds, point sources, and a previously unknown central component of hard X-ray emission (CHXE). NuSTAR detects four non-thermal X-ray filaments, extending the detection of their power-law spectra with Γ ∼ 1.3–2.3 up to ∼50 keV. A morphological and spectral study of the filaments suggests that their origin may be heterogeneous, where previous studies suggested a common origin in young pulsar wind nebulae (PWNe). NuSTAR detects non-thermal X-ray continuum emission spatially correlated with the 6.4 keV Fe Kα fluorescence line emission associated with two Sgr A molecular clouds: MC1 and the Bridge. Broadband X-ray spectral analysis with a Monte-Carlo based X-ray reflection model self-consistently determined their intrinsic column density (∼10{sup 23} cm{sup −2}), primary X-ray spectra (power-laws with Γ ∼ 2) and set a lower limit of the X-ray luminosity of Sgr A* flare illuminating the Sgr A clouds to L{sub X} ≳ 10{sup 38} erg s{sup −1}. Above ∼20 keV, hard X-ray emission in the central 10 pc region around Sgr A* consists of the candidate PWN G359.95–0.04 and the CHXE, possibly resulting from an unresolved population of massive CVs with white dwarf masses M{sub WD} ∼ 0.9 M{sub ⊙}. Spectral energy distribution analysis suggests that G359.95–0.04 is likely the hard X-ray counterpart of the ultra-high gamma-ray source HESS J1745–290, strongly favoring a leptonic origin of the GC TeV emission.

  19. The Hard X-ray Imager (HXI) for the ASTRO-H Mission

    Science.gov (United States)

    Sato, Goro; Kokubun, Motohide; Nakazawa, Kazuhiro; Enoto, Teruaki; Fukazawa, Yasushi; Harayama, Atsushi; Hayashi, Katsuhiro; Kataoka, Jun; Katsuta, Junichiro; Kawaharada, Madoka; Laurent, Philippe; Lebrun, François; Limousin, Olivier; Makishima, Kazuo; Mizuno, Tsunefumi; Mori, Kunishiro; Nakamori, Takeshi; Noda, Hirofumi; Odaka, Hirokazu; Ohno, Masanori; Ohta, Masayuki; Saito, Shinya; Sato, Rie; Tajima, Hiroyasu; Takahashi, Hiromitsu; Takahashi, Tadayuki; Takeda, Shinichiro; Terada, Yukikatsu; Uchiyama, Hideki; Uchiyama, Yasunobu; Watanabe, Shin; Yamaoka, Kazutaka; Yatsu, Yoichi; Yuasa, Takayuki

    2014-07-01

    The 6th Japanese X-ray satellite, ASTRO-H, is scheduled for launch in 2015. The hard X-ray focusing imaging system will observe astronomical objects with the sensitivity for detecting point sources with a brightness of 1/100,000 times fainter than the Crab nebula at > 10 keV. The Hard X-ray Imager (HXI) is a focal plane detector 12 m below the hard X-ray telescope (HXT) covering the energy range from 5 to 80 keV. The HXI is composed of a stacked Si/CdTe semiconductor detector module and surrounding BGO scintillators. The latter work as active shields for efficient reduction of background events caused by cosmic-ray particles, cosmic X-ray background, and in-orbit radiation activation. In this paper, we describe the detector system, and present current status of flight model development, and performance of HXI using an engineering model of HXI.

  20. Calibration of a time-resolved hard-x-ray detector using radioactive sources

    Energy Technology Data Exchange (ETDEWEB)

    Stoeckl, C., E-mail: csto@lle.rochester.edu; Theobald, W.; Regan, S. P.; Romanofsky, M. H. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623-1299 (United States)

    2016-11-15

    A four-channel, time-resolved, hard x-ray detector (HXRD) has been operating at the Laboratory for Laser Energetics for more than a decade. The slope temperature of the hot-electron population in direct-drive inertial confinement fusion experiments is inferred by recording the hard x-ray radiation generated in the interaction of the electrons with the target. Measuring the energy deposited by hot electrons requires an absolute calibration of the hard x-ray detector. A novel method to obtain an absolute calibration of the HXRD using single photons from radioactive sources was developed, which uses a thermoelectrically cooled, low-noise, charge-sensitive amplifier.

  1. Hard X-ray brightening of Ginga 1843+009 seen by INTEGRAL

    DEFF Research Database (Denmark)

    Leyder, J.-C.; Chenevez, Jérôme; Fiocchi, M.T.

    2005-01-01

    The transient X-ray pulsar, Ginga 1843+009, appears to be undergoing a hard X-ray outburst brighter than the one reported in May 2003 (ATEL #159). The source has been observed during ISWT observations of the Scutum Arm region with INTEGRAL and was first detected when the source was in the field o...

  2. Hard X-ray bursts and DD microfusion neutrons from complex ...

    Indian Academy of Sciences (India)

    1Institute for High Temperatures of Russian Academy of Sciences, 13/19 Izhorskaya Str.,. 125412 Moscow, Russia ... explosive destruction of micrograins is accompanied by X-ray radiation (during hydrody- namic expansion, cooling ... makes it possible to produce lasing in hard X-rays due to the effects of multiple scattering.

  3. Hard X-ray Spectroscopy of Obscured AGN with NuSTAR

    Science.gov (United States)

    Balokovic, Mislav; Harrison, Fiona; NuSTAR Extragalactic Surveys Team

    2017-01-01

    The Nuclear Spectroscopic Telescope Array (NuSTAR) has enabled studies of the local active galactic nuclei (AGN) to extend into the hard X-ray band, up to 79 keV, with unprecedented spatial resolution and sensitivity. As a part of its extragalactic program, NuSTAR is surveying the nearby population of AGN detected at hard X-ray energies by the Swift Burst Alert Telescope (Swift/BAT), selecting even the most obscured local AGN. I will highlight some of the results based on broadband X-ray spectroscopy of individual targets and present my work on the large representative sample of more than a hundred nearby obscured AGN, which constitutes the largest available atlas of hard X-ray spectra of obscured AGN to date. The high quality of the data allows us to probe the details of AGN structures such as the X-ray-emitting corona and the toroidal obscurer in the under-explored spectral window above 10 keV. I will present both phenomenological results important for synthesis models of the cosmic X-ray background, and a novel approach for constraining the geometry of the gas surrounding the supermassive black hole (including the accretion disk, the broad-line region, and the torus) from the hard X-ray band. Finally, I will discuss how what we learned from this survey of local AGN relates to deeper high-redshift X-ray surveys and AGN structure probes at other wavelengths.

  4. Hard X-ray bursts and DD microfusion neutrons from complex ...

    Indian Academy of Sciences (India)

    Hard X-ray emission efficiency, generation of energetic ions (∼ 1 MeV) and neutrons, trapping and releasing of fast ions and/or X-rays from interelectrode aerosol ensembles are the subject of our study. The neutrons from DD microfusion, as well as the modelling of some interstellar nuclear burning due to microexplosive ...

  5. Deterministic retrieval of complex Green's functions using hard X rays.

    Science.gov (United States)

    Vine, D J; Paganin, D M; Pavlov, K M; Uesugi, K; Takeuchi, A; Suzuki, Y; Yagi, N; Kämpfe, T; Kley, E-B; Förster, E

    2009-01-30

    A massively parallel deterministic method is described for reconstructing shift-invariant complex Green's functions. As a first experimental implementation, we use a single phase contrast x-ray image to reconstruct the complex Green's function associated with Bragg reflection from a thick perfect crystal. The reconstruction is in excellent agreement with a classic prediction of dynamical diffraction theory.

  6. Hard X-ray irradiation of cosmic silicate analogs: structural evolution and astrophysical implications

    Science.gov (United States)

    Gavilan, L.; Jäger, C.; Simionovici, A.; Lemaire, J. L.; Sabri, T.; Foy, E.; Yagoubi, S.; Henning, T.; Salomon, D.; Martinez-Criado, G.

    2016-03-01

    Context. Protoplanetary disks, interstellar clouds, and active galactic nuclei contain X-ray-dominated regions. X-rays interact with the dust and gas present in such environments. While a few laboratory X-ray irradiation experiments have been performed on ices, X-ray irradiation experiments on bare cosmic dust analogs have been scarce up to now. Aims: Our goal is to study the effects of hard X-rays on cosmic dust analogs via in situ X-ray diffraction. By using a hard X-ray synchrotron nanobeam, we seek to simulate cumulative X-ray exposure on dust grains during their lifetime in these astrophysical environments and provide an upper limit on the effect of hard X-rays on dust grain structure. Methods: We prepared enstatite (MgSiO3) nanograins, which are analogs to cosmic silicates, via the melting-quenching technique. These amorphous grains were then annealed to obtain polycrystalline grains. These were characterized via scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM) before irradiation. Powder samples were prepared in X-ray transparent substrates and were irradiated with hard X-rays nanobeams (29.4 keV) provided by beamline ID16B of the European Synchrotron Radiation Facility (Grenoble). X-ray diffraction images were recorded in transmission mode, and the ensuing diffractograms were analyzed as a function of the total X-ray exposure time. Results: We detected the amorphization of polycrystalline silicates embedded in an organic matrix after an accumulated X-ray exposure of 6.4 × 1027 eV cm-2. Pure crystalline silicate grains (without resin) do not exhibit amorphization. None of the amorphous silicate samples (pure and embedded in resin) underwent crystallization. We analyze the evolution of the polycrystalline sample embedded in an organic matrix as a function of X-ray exposure. Conclusions: Loss of diffraction peak intensity, peak broadening, and the disappearance of discrete spots and arcs reveal the amorphization

  7. AN OSCILLATOR CONFIGURATION FOR FULL REALIZATION OF HARD X-RAY FREE ELECTRON LASER*

    Energy Technology Data Exchange (ETDEWEB)

    Kim, K.-J.; Kolodziej, T.; Lindberg, R. R.; Shu, D.; Shvyd' ko, Y.; Stoupin, S.; Maxwell, T.J.; Ding, Y.; Fawley, W. M.; Hastings, J.; Huang, Z; Krzywinski, J.; Marcus, G.; Qin, Weilun; Medvedev, N.; Zemella, J.; Blank, V.; Terentyev, S.

    2017-06-01

    An x-ray free electron laser oscillator (XFELO) is feasible by employing an X-ray cavity with Bragg mirrors such as diamond crystals. An XFELO at the 5th harmonic frequency may be implemented at the LCLS II using its 4 GeV superconducting linac, producing stable, fully coherent, high-spectral-purity hard x-rays. In addition, its output can be a coherent seed to the LCLS amplifier for stable, high-power, femto-second x-ray pulses. We summarize the recent progress in various R&D efforts addressing critical issues for realizing an XFELO at LCLS II.

  8. Hard disk drive based microsecond x-ray chopper for characterization of ionization chambers and photodiodes

    Energy Technology Data Exchange (ETDEWEB)

    Müller, O., E-mail: o.mueller@uni-wuppertal.de; Lützenkirchen-Hecht, D.; Frahm, R. [Bergische Universität Wuppertal, Gaußstraße 20, Wuppertal 42119 (Germany)

    2015-03-15

    A fast X-ray chopper capable of producing ms long X-ray pulses with a typical rise time of few μs was realized. It is ideally suited to investigate the temporal response of X-ray detectors with response times of the order of μs to ms, in particular, any kind of ionization chambers and large area photo diodes. The drive mechanism consists of a brushless DC motor and driver electronics from a common hard disk drive, keeping the cost at an absolute minimum. Due to its simple construction and small dimensions, this chopper operates at home lab based X-ray tubes and synchrotron radiation sources as well. The dynamics of the most important detectors used in time resolved X-ray absorption spectroscopy, namely, ionization chambers and Passivated Implanted Planar Silicon photodiodes, were investigated in detail. The results emphasize the applicability of this X-ray chopper.

  9. X-ray optical simulations supporting advanced commissioning of the coherent hard x-ray beamline at NSLS-II

    Science.gov (United States)

    Wiegart, L.; Rakitin, M.; Fluerasu, A.; Chubar, O.

    2017-08-01

    We present the application of fully- and partially-coherent synchrotron radiation wavefront propagation simulation functions, implemented in the "Synchrotron Radiation Workshop" computer code, to create a `virtual beamline' mimicking the Coherent Hard X-ray scattering beamline at NSLS-II. The beamline simulation includes all optical beamline components, such as the insertion device, mirror with metrology data, slits, double crystal monochromator and refractive focusing elements (compound refractive lenses and kinoform lenses). A feature of this beamline is the exploitation of X-ray beam coherence, boosted by the low-emittance NSLS-II storage-ring, for techniques such as X-ray Photon Correlation Spectroscopy or Coherent Diffraction Imaging. The key performance parameters are the degree of Xray beam coherence and photon flux, and the trade-off between them needs to guide the beamline settings for specific experimental requirements. Simulations of key performance parameters are compared to measurements obtained during beamline commissioning, and include the spectral flux of the undulator source, the degree of transverse coherence as well as focal spot sizes.

  10. Hard X-ray emission spectroscopy with pink beam

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-06-01

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

  11. Linking Jet Emission, X-Ray States, and Hard X-Ray Tails in the Neutron Star X-Ray Binary GX 17+2

    NARCIS (Netherlands)

    Migliari, S.; Miller-Jones, J.C.A.; Fender, R.P.; Homan, J.; di Salvo, T.; Rothschild, R.E.; Rupen, M.P.; Tomsick, J.A.; Wijnands, R.; van der Klis, M.

    2007-01-01

    We present the results of simultaneous radio (VLA) and X-ray (RXTE) observations of the Z-type neutron star X-ray binary GX 17+2. The aim is to assess the coupling between X-ray and radio properties throughout its three rapidly variable X-ray states and during the time-resolved transitions. These

  12. Design of grazing-incidence multilayer supermirrors for hard-X-ray reflectors

    DEFF Research Database (Denmark)

    Joensen, K. D.; Voutov, P.; Szentgyorgyi, A.

    1995-01-01

    Extremely broadband grazing-incidence multilayers for hard-X-ray reflection can be obtained by a gradual change of the layer thicknesses down through the structure. Existing approaches for designing similar neutron optics, called supermirrors, are shown to provide respectable performance when...... applied to X-ray multilayers. However, none of these approaches consider the effects of imperfect layer interfaces and absorption in the overlying layers. Adaptations of neutron designs that take these effects into account are presented, and a thorough analysis of two specific applications (a single hard-X-ray...... reflector and a hard-X-ray telescope) shows that an improved performance can be obtained. A multilayer whose bilayer thicknesses are given by a power law expression is found to provide the best solution; however, it is only slightly better than some of the adapted neutron designs...

  13. Zone Plates for Hard X-Ray FEL Radiation

    Science.gov (United States)

    Nilsson, D.; Holmberg, A.; Sinn, H.; Vogt, U.

    2011-09-01

    We investigated theoretically the use of zone plates for the focusing of the European X-ray Free Electron Laser (XFEL). In a finite-element simulation the heat load on zone plates placed in the high intensity x-ray beam was simulated for four different zone plate materials: gold, iridium, tungsten, and CVD diamond. The main result of the calculations is that all zone plates remain below the melting temperature throughout a full XFEL pulse train of 3000 pulses. However, if the zone plate is placed in the direct beam it will experience large and rapid temperature fluctuations on the order of 300 K. The situation is relaxed if the optic is placed behind a monochromator and the fluctuations are reduced to around 20 K. Besides heat load, the maximization of the total efficiency of the complete optical system is an important issue. We calculated the efficiency of different zone plates and monochromator systems and found that the final beam size of the XFEL in combination with its monochromaticity will be important parameters.

  14. [The Development of Luminescent Nano-probes on Hard X-ray Irradiation].

    Science.gov (United States)

    Osakada, Yasuko

    2016-01-01

      X-rays are widely used in imaging applications such as diffraction imaging of crystals and medical imaging. In particular, X-ray computed tomography (CT) is a critical tool for clinical and disease diagnostics. The principle of conventional CT is based on X-ray attenuation caused by photoelectric absorption and scattering. In addition to conventional CT, a number of novel methodologies are presently under development, including state-of-the-art instrument technologies and chemical probes to fulfill diagnosis criteria. Among these novel methodologies, we have utilized hard X-ray-excited optical luminescence (hXEOL) as a new methodology to enhance the contrast of the image. Herein, we explored the possibility of hXEOL via iridium-doped polymer nanoparticles and biomolecule-directed metal clusters and propose it as a potential platform for new X-ray imaging.

  15. Performance of ASTRO-H Hard X-Ray Telescope (HXT)

    Science.gov (United States)

    Awaki, Hisamitsu; Kunieda, Hideyo; Ishida, Manabu; Matsumoto, Hironori; Furuzawa, Akihiro; Haba, Yohsito; Hayashi, Takayuki; Iizuka, Ryo; Ishibashi, Kazunori; Itoh, Masayuki; hide

    2016-01-01

    The Japanese X-ray Astronomy Satellite, Hitomi (ASTRO-H) carries hard X-ray imaging system, covering the energy band from 5 keV to 80 keV. The hard X-ray imaging system consists of two hard X-ray telescopes (HXT) and two hard X-ray imagers (HXI). The HXT employs tightly-nested, conically-approximated thin foil Wolter-I optics. The mirror surfaces of HXT were coated with PtC depth-graded multilayers. We carried out ground calibrations of HXTs at the synchrotron radiation facility SPring-8 BL20B2 in Japan, and found that total effective area of two HXTs was about 350 sq cm at 30 keV, and the half power diameter of HXT was about 1.9. After the launch of Hitomi, Hitomi observed several targets during the initial functional verification of the onboard instruments. The Hitomi software and calibration team (SCT) provided the Hitomis data of G21.5-0.9, a pulsar wind nebula, to the hardware team for the purpose of the instrument calibration. Through the analysis of the in-flight data, we have confirmed that the X-ray performance of HXTs in orbit was consistent with that estimated by the ground calibrations.

  16. Coherent Diffraction Imaging with Hard X-Ray Waveguides

    Science.gov (United States)

    Caro, Liberato De; Giannini, Cinzia; Pelliccia, Daniele; Cedola, Alessia; Lagomarsino, Stefano

    2013-01-01

    Coherent X-ray diffraction imaging (CXDI) has been widely applied in the nanoscopic world, offering nanometric-scale imaging of noncrystallographic samples, and permitting the next-generation structural studies on living cells, single virus particles and biomolecules. The use of curved wavefronts in CXDI has caused a tidal wave in the already promising application of this emergent technique. The non-planarity of the wavefront allows to accelerate any iterative phase-retrieval process and to guarantee a reliable and unique solution. Nowadays, successful experiments have been performed with Fresnel zone plates and planar waveguides as optical elements. Here we describe the use of a single planar waveguide as well as two crossed waveguides in the experiments which first showed this optical element a promising tool for producing a line- or point-like coherent source, respectively.

  17. Impact of a Vertically Polarized Undulator on LCLS Hard X-ray Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Fritz, David [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2014-11-14

    The LCLS-II project will install two variable gap, horizontally polarized undulators into the LCLS undulator hall. One undulator is designed to produce soft x-rays spanning an energy range of 200-1250 eV (SXU) while the other is designed for the hard spectral range of 1-25 keV (HXU). The hard x-ray LCLS instruments (X-ray Pump- Probe [XPP], X-ray correlation Spectroscopy [XCS], Coherent X-ray Imaging [CXI], Matter in Extreme Conditions [MEC]) will be repurposed to operate on the HXU line while two new soft x-ray beamlines will be created for the SXU line. An alternate HXU undulator design is being considered that could provide advantages over the present design choice. In particular, the project team is collaborating with Argonne National Laboratory to develop a vertically polarized undulator (VPU). A 1-m prototype VPU device was successfully constructed this year and a full size prototype is in process. A decision to alter the project baseline, which is the construction of a horizontally polarized device, must be made in the coming weeks to not impact the present project schedule. Please note that a change to the soft x-ray undulator is not under discussion at the moment.

  18. Design and Tests of the Hard X-Ray Polarimeter X-Calibur

    Science.gov (United States)

    Beilicke, M.; Baring, M. G.; Barthelmy, S.; Binns, W. R.; Buckley, J.; Cowsik, R.; Dowkontt, P.; Garson, A.; Guo, Q.; Haba, Y.; hide

    2012-01-01

    X-ray polarimetry promises to give qualitatively new information about high-energy astrophysical sources, such as binary black hole systems, micro-quasars, active galactic nuclei, and gamma-ray bursts. We designed, built and tested a hard X-ray polarimeter X-Calibur to be used in the focal plane of the InFOC(mu)S grazing incidence hard X-ray telescope. X-Calibur combines a low-Z Compton scatterer with a CZT detector assembly to measure the polarization of 10 - 80 keY X-rays making use of the fact that polarized photons Compton scatter preferentially perpendicular to the electric field orientation. X-Calibur achieves a high detection efficiency of order unity.

  19. Beam-induced damage on diffractive hard X-ray optics.

    Science.gov (United States)

    Nygård, K; Gorelick, S; Vila-Comamala, J; Färm, E; Bergamaschi, A; Cervellino, A; Gozzo, F; Patterson, B D; Ritala, M; David, C

    2010-11-01

    The issue of beam-induced damage on diffractive hard X-ray optics is addressed. For this purpose a systematic study on the radiation damage induced by a high-power X-ray beam is carried out in both ambient and inert atmospheres. Diffraction gratings fabricated by three different techniques are considered: electroplated Au gratings both with and without the polymer mold, and Ir-coated Si gratings. The beam-induced damage is monitored by X-ray diffraction and evaluated using scanning electron microscopy.

  20. Ptychographic characterization of the wavefield in the focus of reflective hard X-ray optics.

    Science.gov (United States)

    Kewish, Cameron M; Thibault, Pierre; Dierolf, Martin; Bunk, Oliver; Menzel, Andreas; Vila-Comamala, Joan; Jefimovs, Konstantins; Pfeiffer, Franz

    2010-03-01

    A technique for quantitatively characterizing the complex-valued focal wavefield of arbitrary optics is described and applied to reconstructing the coherent focused beam produced by a reflective/diffractive hard X-ray mirror. This phase-retrieval method, based on ptychography, represents an important advance in X-ray optics characterization because the information obtained and potential resolution far exceeds that accessible to methods of directly probing the focus. Ptychography will therefore be well-suited for characterizing and aligning future nanofocusing X-ray optics. (c) 2010 Elsevier B.V. All rights reserved.

  1. Fabrication and characterization of multilayer supermirrors for hard X-ray optics.

    Science.gov (United States)

    Yamashita, K; Akiyama, K; Haga, K; Kunieda, H; Lodha, G S; Nakajo, N; Nakamura, N; Okajima, T; Tamura, K; Tawara, Y

    1998-05-01

    Multilayer supermirrors stacked with three sets of Pt/C combinations have been fabricated on a flat float-glass and conical replica foil mirror using a magnetron DC sputtering system, and applied to X-ray optical systems in the hard X-ray region. The design of the supermirror is optimized to obtain the highest integrated reflectivity in the energy band and at the grazing angle concerned. X-ray reflectivities of 30% in the 25-35 keV band at an incidence angle of 0.3 degrees were obtained.

  2. Coherent hard x rays from attosecond pulse train-assisted harmonic generation.

    Science.gov (United States)

    Klaiber, Michael; Hatsagortsyan, Karen Z; Müller, Carsten; Keitel, Christoph H

    2008-02-15

    High-order harmonic generation from atomic systems is considered in the crossed fields of a relativistically strong infrared laser and a weak attosecond pulse train of soft x rays. Due to one-photon ionization by the x-ray pulse, the ionized electron obtains a starting momentum that compensates the relativistic drift, which is induced by the laser magnetic field, and allows the electron to efficiently emit harmonic radiation upon recombination with the atomic core in the relativistic regime. This way, short pulses of coherent hard x rays of up to 40 keV energy can be generated.

  3. The influence of albedo on the size of hard X-ray flare sources

    OpenAIRE

    Battaglia, Marina; Kontar, Eduard P.; Hannah, Iain G.

    2010-01-01

    Context: Hard X-rays from solar flares are an important diagnostic of particle acceleration and transport in the solar atmosphere. Any observed X-ray flux from on-disc sources is composed of direct emission plus Compton backscattered photons (albedo). This affects both the observed spectra and images as well as the physical quantities derived from them such as the spatial and spectral distributions of accelerated electrons or characteristics of the solar atmosphere. Aims: We propose a new ind...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-11-21

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

  5. The HERO Program: High-Energy Replicated Optics for a Hard-X-Ray Balloon Payload

    Science.gov (United States)

    Ramsey, B. D.; Engelhaupt, D.; Speegle, C. O.; Austin, R. A.; Kolodziejczak, J. J.; ODell, S. L.; Weisskopf, M. C.

    1999-01-01

    We are developing high-energy replicated optics for a balloon-borne hard-x-ray telescope. When completed, the telescope will have around 150 square cm of effective collecting area up to 65 keV, and an angular resolution of around 30 arc seconds, half power diameter. When used in conjunction with an array of focal plane imaging detectors, for which Gas Scintillation Proportional Counters are under development, the payload will provide unprecedented sensitivity for pointed observations in the hard-x-ray band. We will present an overview of the High Energy Replicated Optics (HERO) program together with test data from the first mirror units. The overall sensitivity of the full payload, when flown on long- and ultra-long-duration balloon flights, will be compared with past and planned satellite-borne hard-x-ray missions.

  6. TRACING THE REVERBERATION LAG IN THE HARD STATE OF BLACK HOLE X-RAY BINARIES

    Energy Technology Data Exchange (ETDEWEB)

    De Marco, B.; Ponti, G.; Nandra, K. [Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse 1, D-85748 Garching bei München (Germany); Muñoz-Darias, T., E-mail: bdemarco@mpe.mpg.de [Instituto de Astrofísica de Canarias, E-38205 La Laguna, Tenerife (Spain)

    2015-11-20

    We report results obtained from a systematic analysis of X-ray lags in a sample of black hole X-ray binaries, with the aim of assessing the presence of reverberation lags and studying their evolution during outburst. We used XMM-Newton and simultaneous Rossi X-ray Timing Explorer (RXTE) observations to obtain broadband energy coverage of both the disk and the hard X-ray Comptonization components. In most cases the detection of reverberation lags is hampered by low levels of variability-power signal-to-noise ratio (typically when the source is in a soft state) and/or short exposure times. The most detailed study was possible for GX 339-4 in the hard state, which allowed us to characterize the evolution of X-ray lags as a function of luminosity in a single source. Over all the sampled frequencies (∼0.05–9 Hz), we observe the hard lags intrinsic to the power-law component, already well known from previous RXTE studies. The XMM-Newton soft X-ray response allows us to detail the disk variability. At low frequencies (long timescales) the disk component always leads the power-law component. On the other hand, a soft reverberation lag (ascribable to thermal reprocessing) is always detected at high frequencies (short timescales). The intrinsic amplitude of the reverberation lag decreases as the source luminosity and the disk fraction increase. This suggests that the distance between the X-ray source and the region of the optically thick disk where reprocessing occurs gradually decreases as GX 339-4 rises in luminosity through the hard state, possibly as a consequence of reduced disk truncation.

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

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Xiaojing [Brookhaven National Lab. (BNL), Upton, NY (United States); Conley, Raymond [Brookhaven National Lab. (BNL), Upton, NY (United States); Argonne National Lab. (ANL), Argonne, IL (United States); Bouet, Nathalie [Brookhaven National Lab. (BNL), Upton, NY (United States); Zhou, Juan [Brookhaven National Lab. (BNL), Upton, NY (United States); Macrander, Albert [Argonne National Lab. (ANL), Argonne, IL (United States); Maser, Jorg [Argonne National Lab. (ANL), Argonne, IL (United States); Yan, Hanfei [Brookhaven National Lab. (BNL), Upton, NY (United States); Nazaretski, Evgeny [Brookhaven National Lab. (BNL), Upton, NY (United States); Lauer, Kenneth [Brookhaven National Lab. (BNL), Upton, NY (United States); Harder, Ross [Argonne National Lab. (ANL), Argonne, IL (United States); Robinson, Ian K. [Univ. College London, Bloomsbury (United Kingdom); Research Complex at Harwell, Oxfordshire (United Kingdom); Kalbfleisch, Sebastian [Brookhaven National Lab. (BNL), Upton, NY (United States); Chu, Yong S. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-05-04

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

  8. Design and Tests of the Hard X-ray Polarimeter X-Calibur

    Directory of Open Access Journals (Sweden)

    M. Beilicke

    2014-12-01

    Full Text Available X-ray polarimetry promises to give qualitatively new information bout high-energy astrophysical sources, such as binary black hole  systems, micro-quasars, active galactic nuclei, and gamma-ray bursts. We designed, built and tested ahard X-ray polarimeter, X-Calibur, to be used in the focal plane of the InFOCuS grazing incidence hard X-ray telescope.X-Calibur combines a low-Z Compton scatterer with a CZT detector assembly to measure the polarization of 20−60 keV X-rays making use of the fact that polarized photons Compton scatter preferentially perpendicular to the electric field orientation; in principal, a similar space-borne experiment could be operated in the 5−100 keV regime. X-Calibur achieves a high detection efficiency of order unity.

  9. Cosmological evolution of supermassive black holes in galactic centers unveiled by hard X-ray observations.

    Science.gov (United States)

    Ueda, Yoshihiro

    2015-01-01

    We review the current understanding of the cosmological evolution of supermassive black holes in galactic centers elucidated by X-ray surveys of active galactic nuclei (AGNs). Hard X-ray observations at energies above 2 keV are the most efficient and complete tools to find "obscured" AGNs, which are dominant populations among all AGNs. Combinations of surveys with various flux limits and survey area have enabled us to determine the space number density and obscuration properties of AGNs as a function of luminosity and redshift. The results have essentially solved the origin of the X-ray background in the energy band below ∼10 keV. The downsizing (or anti-hierarchical) evolution that more luminous AGNs have the space-density peak at higher redshifts has been discovered, challenging theories of galaxy and black hole formation. Finally, we summarize unresolved issues on AGN evolution and prospects for future X-ray missions.

  10. Detection of hard X-ray emission from the Galactic nuclear region with INTEGRAL

    DEFF Research Database (Denmark)

    Belanger, G.; Goldwurm, A.; Goldoni, P.

    2004-01-01

    , in the energy ranges 20 - 40 and 40 - 100 keV. These give a yet unseen view of the high-energy sources of this region in hard X-rays and gamma rays with an angular resolution of 12' (FWHM). We report on the discovery of a source, IGR J1745.6 - 2901, coincident with the Galactic nucleus Sgr A* to within 0......, this is the first report of significant hard X-ray emission from within the inner 10' of the Galaxy and a contribution from the Galactic supermassive black hole itself cannot be excluded....

  11. Thick and large area PIN diodes for hard X-ray astronomy

    CERN Document Server

    Ota, N; Sugizaki, M; Kaneda, M; Tamura, T; Ozawa, H; Kamae, T; Makishima, K; Takahashi, T; Tashiro, M; Fukazawa, Y; Kataoka, J; Yamaoka, K; Kubo, S; Tanihata, C; Uchiyama, Y; Matsuzaki, K; Iyomoto, N; Kokubun, M; Nakazawa, T; Kubota, A; Mizuno, T; Matsumoto, Y; Isobe, N; Terada, Y; Sugiho, M; Onishi, T; Kubo, H; Ikeda, H; Nomachi, M; Ohsugi, T; Muramatsu, M; Akahori, H

    1999-01-01

    Thick and large area PIN diodes for the hard X-ray astronomy in the 10-60 keV range are developed. To cover this energy range in a room temperature and in a low background environment, Si PIN junction diodes of 2 mm in thickness with 2.5 cm sup 2 in effective area were developed, and will be used in the bottom of the Phoswich Hard X-ray Detector (HXD), on-board the ASTRO-E satellite. Problems related to a high purity Si and a thick depletion layer during our development and performance of the PIN diodes are presented in detail.

  12. A HARD X-RAY POWER-LAW SPECTRAL CUTOFF IN CENTAURUS X-4

    Energy Technology Data Exchange (ETDEWEB)

    Chakrabarty, Deepto; Nowak, Michael A. [MIT Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Tomsick, John A.; Boggs, Steven E.; Craig, William W. [Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States); Grefenstette, Brian W.; Fürst, Felix; Harrison, Fiona A.; Rana, Vikram [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Psaltis, Dimitrios [Department of Astronomy, University of Arizona, Tucson, AZ 85721 (United States); Bachetti, Matteo; Barret, Didier [Observatoire Midi-Pyrénées, Université de Toulouse III - Paul Sabatier, F-31400 Toulouse (France); Christensen, Finn E. [Division of Astrophysics, National Space Institute, Technical University of Denmark, DK-2800 Lyngby (Denmark); Hailey, Charles J. [Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); Kaspi, Victoria M. [Department of Physics, McGill University, Montreal, PQ H3A 2T8 (Canada); Miller, Jon M. [Department of Astronomy, University of Michigan, Ann Arbor, MI 48109 (United States); Stern, Daniel [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Wik, Daniel R.; Zhang, William W. [Astrophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Wilms, Jörn, E-mail: deepto@mit.edu [Dr. Karl-Remeis-Sternwarte and Erlangen Centre for Astroparticle Physics, Universität Erlangen-Nürnberg, D-96049 Bamberg (Germany)

    2014-12-20

    The low-mass X-ray binary (LMXB) Cen X-4 is the brightest and closest (<1.2 kpc) quiescent neutron star transient. Previous 0.5-10 keV X-ray observations of Cen X-4 in quiescence identified two spectral components: soft thermal emission from the neutron star atmosphere and a hard power-law tail of unknown origin. We report here on a simultaneous observation of Cen X-4 with NuSTAR (3-79 keV) and XMM-Newton (0.3-10 keV) in 2013 January, providing the first sensitive hard X-ray spectrum of a quiescent neutron star transient. The 0.3-79 keV luminosity was 1.1×10{sup 33} D{sub kpc}{sup 2} erg s{sup –1}, with ≅60% in the thermal component. We clearly detect a cutoff of the hard spectral tail above 10 keV, the first time such a feature has been detected in this source class. We show that thermal Comptonization and synchrotron shock origins for the hard X-ray emission are ruled out on physical grounds. However, the hard X-ray spectrum is well fit by a thermal bremsstrahlung model with kT{sub e} = 18 keV, which can be understood as arising either in a hot layer above the neutron star atmosphere or in a radiatively inefficient accretion flow. The power-law cutoff energy may be set by the degree of Compton cooling of the bremsstrahlung electrons by thermal seed photons from the neutron star surface. Lower thermal luminosities should lead to higher (possibly undetectable) cutoff energies. We compare Cen X-4's behavior with PSR J1023+0038, IGR J18245–2452, and XSS J12270–4859, which have shown transitions between LMXB and radio pulsar modes at a similar X-ray luminosity.

  13. Hard X-ray variability of V404 Cygni during the 2015 outburst

    Science.gov (United States)

    Sánchez-Fernández, C.; Kajava, J. J. E.; Motta, S. E.; Kuulkers, E.

    2017-06-01

    Aims: Hard X-ray spectra of black hole binaries (BHB) are produced by Comptonization of soft seed photons by hot electrons near the black hole. The slope of the resulting energy spectra is governed by two main parameters: the electron temperature (Te) and optical depth (τ) of the emitting plasma. Given the extreme brightness of V404 Cyg during the 2015 outburst, we aim to constrain the source spectral properties using an unprecedented time resolution in hard X-rays, and to monitor the evolution of Te and τ over the outburst. Methods: We have extracted and analysed 602 X-ray spectra of V404 Cyg obtained by the IBIS/ISGRI instrument on-board INTEGRAL during the 2015 June outburst, using effective integration times ranging between 8 and 176 000 s. We fitted the resulting spectra in the 20-200 keV energy range. Results: We find that while the light curve and soft X-ray spectra of V404 Cyg are remarkably different from those of other BHBs, the spectral evolution of V404 Cyg in hard X-rays and the relations between the spectral parameters are consistent with those observed in other BHBs. We identify a hard branch in which the Te is anti-correlated with the hard X-ray flux, and a soft flaring branch in which the relation reverses. In addition, we find that during long X-ray plateaus detected at intermediate fluxes, the thermal Comptonization models fail to describe the spectra. However, the statistics improve if we allow NH to vary freely in the fits to these spectra. Conclusions: We conclude that the hard branch in V404 Cyg is analogous to the canonical hard state of BHBs. V404 Cyg never seems to enter the canonical soft state, although the soft flaring branch bears resemblance to the BHB intermediate state and ultra-luminous state. The X-ray plateaus are likely the result of absorption by a Compton-thick outflow (NH ≳ 1024 cm-2) which reduces the observed flux by a factor of about 10. Variable covering of the central source by this Compton-thick material may be the

  14. Status of the hard X-ray microprobe beamline ID22 of the European Synchrotron Radiation Facility.

    Science.gov (United States)

    Martínez-Criado, Gema; Tucoulou, Rémi; Cloetens, Peter; Bleuet, Pierre; Bohic, Sylvain; Cauzid, Jean; Kieffer, Isabelle; Kosior, Ewelina; Labouré, Sylvain; Petitgirard, Sylvain; Rack, Alexander; Sans, Juan Angel; Segura-Ruiz, Jaime; Suhonen, Heikki; Susini, Jean; Villanova, Julie

    2012-01-01

    The ESRF synchrotron beamline ID22, dedicated to hard X-ray microanalysis and consisting of the combination of X-ray fluorescence, X-ray absorption spectroscopy, diffraction and 2D/3D X-ray imaging techniques, is one of the most versatile instruments in hard X-ray microscopy science. This paper describes the present beamline characteristics, recent technical developments, as well as a few scientific examples from recent years of the beamline operation. The upgrade plans to adapt the beamline to the growing needs of the user community are briefly discussed.

  15. A bright point source of ultrashort hard x-rays from laser bioplasmas

    CERN Document Server

    Krishnamurthy, M; Lad, Amit D; Ahmad, Saima; Narayanan, V; Rajeev, R; Kundu, M; Kumar, G Ravindra; Ray, Krishanu

    2010-01-01

    Micro and nano structures scatter light and amplify local electric fields very effectively. Energy incident as intense ultrashort laser pulses can be converted to x-rays and hot electrons more efficiently with a substrate that suitably modifies the local fields. Here we demonstrate that coating a plain glass surface with a few micron thick layer of an ubiquitous microbe, {\\it Escherichia coli}, catapults the brightness of hard x-ray bremsstrahlung emission (up to 300 keV) by more than two orders of magnitude at an incident laser intensity of 10$^{16}$ W cm$^{-2}$. This increased yield is attributed to the local enhancement of electric fields around individual {\\it E. coli} cells and is reproduced by detailed particle-in-cell (PIC) simulations. This combination of laser plasmas and biological targets can lead to turnkey, multi-kilohertz and environmentally safe sources of hard x-rays.

  16. Rapid X-ray variability properties during the unusual very hard state in neutron-star low-mass X-ray binaries

    Science.gov (United States)

    Wijnands, R.; Parikh, A. S.; Altamirano, D.; Homan, J.; Degenaar, N.

    2017-11-01

    Here, we study the rapid X-ray variability (using XMM-Newton observations) of three neutron-star low-mass X-ray binaries (1RXS J180408.9-342058, EXO 1745-248 and IGR J18245-2452) during their recently proposed very hard spectral state. All our systems exhibit a strong to very strong noise component in their power density spectra (rms amplitudes ranging from 34 per cent to 102 per cent) with very low characteristic frequencies (as low as 0.01 Hz). These properties are more extreme than what is commonly observed in the canonical hard state of neutron-star low-mass X-ray binaries observed at X-ray luminosities similar to those we observe from our sources. This suggests that indeed the very hard state is a spectral-timing state distinct from the hard state, although we argue that the variability behaviour of IGR J18245-2452 is very extreme and possibly this source was in a very unusual state. We also compare our results with the rapid X-ray variability of the accreting millisecond X-ray pulsars IGR J00291+5934 and Swift J0911.9-6452 (also using XMM-Newton data) for which previously similar variability phenomena were observed. Although their energy spectra (as observed using the Swift X-ray telescope) were not necessarily as hard (i.e. for Swift J0911.9-6452) as for our other three sources, we conclude that likely both sources were also in very similar state during their XMM-Newton observations. This suggests that different sources that are found in this new state might exhibit different spectral hardness and one has to study both the spectral and the rapid variability to identify this unusual state.

  17. The Hard X-Ray Emission of the Blazar PKS 2155-304

    Science.gov (United States)

    Gaur, Haritma; Chen, Liang; Misra, R.; Sahayanathan, S.; Gu, M. F.; Kushwaha, P.; Dewangan, G. C.

    2017-12-01

    The synchrotron peak of the X-ray bright High Energy Peaked Blazar PKS 2155-304 occurs in the UV-EUV region and hence its X-ray emission (0.6-10 keV) lies mostly in the falling part of the synchrotron hump. We aim to study the X-ray emission of PKS 2155-304 during different intensity states in 2009-2014 using the XMM-Newton satellite. We studied the spectral curvature of all of the observations to provide crucial information on the energy distribution of the nonthermal particles. Most of the observations show curvature or deviation from a single power law and can be well modeled by a log parabola model. In some of the observations, we find spectral flattening after 6 keV. In order to find the possible origin of the X-ray excess, we built the Multiband Spectral Energy distribution. We find that the X-ray excess in PKS 2155-304 is difficult to fit in the one zone model but, could be easily reconciled in the spine/layer jet structure. The hard X-ray excess can be explained by the inverse Comptonization of the synchrotron photons (from the layer) by the spine electrons.

  18. Characterisation and application of a laser-based hard x-ray source

    Energy Technology Data Exchange (ETDEWEB)

    Graetz, M

    1998-11-01

    Hard X-rays are generated by focusing 110 fs laser pulses with intensities of about 1017 W/cm{sup 2} onto solid metal targets. Characteristic properties of this X-ray source are the small source size, the short pulse duration and the high peak flux. The aim of the present work was to characterise this X-ray source and to demonstrate possible applications. A comparison with other X-ray sources and conventional imaging techniques is made. Characterising measurements were performed, including source size, emission spectrum, temporal behaviour, source stability and the influence of various laser parameters. The emission spectrum was measured using both energy-dispersive solid-state detectors and wavelength-dispersive crystal spectroscopy. The conversion efficiency from laser light to X-ray radiation was measured for different target materials. The laser ablation from different targets was studied. The feasibility of special imaging techniques, e.g. differential imaging and time-gated imaging, was investigated both theoretically and experimentally. Differential imaging allows for selective imaging of contrast agents, while time-gated imaging can reduce the influence of scattered radiation in X-ray imaging. Time-gated imaging was demonstrated in different imaging geometries, both for planar imaging and computed tomography imaging. Reasonable agreement between theoretically calculated values and experimental results was obtained 120 refs, figs, tabs

  19. Hard X-ray dose intensity and spatial distribution in a plasma focus ...

    Indian Academy of Sciences (India)

    type PF device in various pressures of argon as the operating gas were studied. The PF device was powered by a 12 F capacitor at 25 kV charging voltage. Time-integrated hard X-ray (HXR) emission was investigated using thermoluminescence ...

  20. The First Focused Hard X-Ray Images of the Sun With NuSTAR

    DEFF Research Database (Denmark)

    Grefenstette, Brian W.; Glesener, Lindsay; Krucker, Sam

    2016-01-01

    We present results from the the first campaign of dedicated solar observations undertaken by the Nuclear Spectroscopic Telescope ARray (NuSTAR) hard X-ray (HXR) telescope. Designed as an astrophysics mission, NuSTAR nonetheless has the capability of directly imaging the Sun at HXR energies (>3 ke......, and full-disk HXR images of the Sun....

  1. INTEGRAL discovered a new hard X-ray source: IGRJ17511-3057

    NARCIS (Netherlands)

    Baldovin, C.; Kuulkers, E.; Ferrigno, C.; Bozzo, E.; Chenevez, J.; Brandt, S.; Beckmann, V.; Bird, A.; Domingo, A.; Ebisawa, K.; Jonker, P.; Kretschmar, P.; Markwardt, C.; Oosterbroek, T.; Paizis, A.; Risquez, D.; Sanchez-Fernandez, C.; Shaw, S.; Wijnands, R.

    2009-01-01

    During the latest observations of the Galactic Bulge monitoring (see ATel #438), carried out between 2009-09-12 03:21:34 and 2009-09-12 05:27:22 (UTC), INTEGRAL discovered a new bright hard X-ray source, which we designate IGRJ17511-3057. The source is detected in the INTEGRAL/IBIS mosaic image with

  2. Bragg concentrators for hard (> 10keV) x-ray astronomy: Status report

    DEFF Research Database (Denmark)

    Pareschi, G.; Frontera, F.; Pasqualini, G.

    1997-01-01

    The use of focusing telescopes in hard X-ray (E > 10 keV) astronomy will provide better flux sensitivity and imaging performances with respect to the direct-viewing detectors, utilized until now. We present recent results obtained from our group regarding the possible use of Bragg-diffraction tec...

  3. Preliminary results from the 'HXR' hard X-ray sky survey

    Energy Technology Data Exchange (ETDEWEB)

    Ubertini, P.; Bazzano, A.; LaPadula, C.; Polcaro, V.F.; Zambon, G. (Consiglio Nazionale delle Ricerche, Frascati (Italy). Lab. di Astrofisica Spaziale); Manchanda, R.K. (Tata Inst. of Fundamental Research, Bombay (India))

    1984-01-01

    The authors present the preliminary results of the HXR81M experiment: a one square meter hard X-ray balloon-borne telescope. The detected excesses on 14 sources are given in catalogue form and the spectra, reduced at the top of the atmosphere, of a number of galactic and extragalactic sources are shortly discussed.

  4. In-flight PSF calibration of the NuSTAR hard X-ray optics

    DEFF Research Database (Denmark)

    An, Hongjun; Madsen, Kristin K.; Westergaard, Niels J.

    2014-01-01

    We present results of the point spread function (PSF) calibration of the hard X-ray optics of the Nuclear Spectroscopic Telescope Array (NuSTAR). Immediately post-launch, NuSTAR has observed bright point sources such as Cyg X-1, Vela X-1, and Her X-1 for the PSF calibration. We use the point source...

  5. Hard X-ray/soft gamma-ray telescope designs for future astrophysics missions

    DEFF Research Database (Denmark)

    Ferreira, Desiree Della Monica; Christensen, Finn Erland; Pivovaroff, Michael J.

    2013-01-01

    We present several concept designs of hard X-ray/soft λ-ray focusing telescopes for future astrophysics missions. The designs are based on depth graded multilayer coatings. These have been successfully employed on the NuSTAR mission for energies up to 80 keV. Recent advances in demonstrating...

  6. Study of runaway electrons with Hard X-ray spectrometry of tokamak plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Shevelev, A.; Chugunov, I.; Khilkevitch, E.; Gin, D.; Doinikov, D.; Naidenov, V. [Ioffe Physical-Technical Institute of the Russian Academy of Sciences, Polytechnicheskaya 26, St. Petersburg, 194021 (Russian Federation); Kiptily, V. [EURATOM / CCFE Fusion Association, Abingdon, OX14 3DB (United Kingdom); Plyusnin, V. [Instituto de Plasmas e Fusão Nuclear, Associação EURATOM-IST, Instituto Superior Tecnico, Universidade Tecnica de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Collaboration: EFDA-JET Contributors

    2014-08-21

    Hard-X-ray spectrometry is a tool widely used for diagnostic of runaway electrons in existing tokamaks. In future machines, ITER and DEMO, HXR spectrometry will be useful providing information on runaway electron energy, runaway beam current and its profile during disruption.

  7. Overview of segmented glass optics development for the Constellation-X hard X-ray telescope

    DEFF Research Database (Denmark)

    Hailey, C.J; Christensen, Finn Erland; Craig, W.W.

    2002-01-01

    We report recent work on segmented glass optics for the Constellation-H hard x-ray telescope. This effort seeks to both improve the figure of the free-standing glass substrates, and to refine a newly-developed mounting technology for the substrates. We discuss metrology on recently characterized...

  8. Application of an EMCCD camera for calibration of hard X-ray telescopes

    DEFF Research Database (Denmark)

    Vogel, Julia K.; Pivovaro, Michael J.; Craig, William W.

    2012-01-01

    Recent technological innovations make it feasible to construct effcient hard x-ray telescopes for space-based astronomical missions. Focusing optics are capable of improving the sensitivity in the energy range above 10 keV by orders of magnitude compared to previously used instruments. The last...

  9. Hard X-ray Spectrum of Mkn 421 during the Active Phase

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging Solutions)

    J. Astrophys. Astr. (2001) 22, 145–154. Hard X-ray Spectrum of Mkn 421 during the Active Phase. R. K. Manchanda Tata Institute of Fundamental Research, Colaba, Mumbai 400 005, India e-mail: ravi@tifr.res.in. Received 2001 July 27; accepted 2001 September 27. Abstract. Spectral measurement of Mkn 421 were made ...

  10. Development of a CZT spectroscopic 3D imager prototype for hard X ray astronomy

    DEFF Research Database (Denmark)

    Auricchio, N.; Caroli, E.; Basili, A.

    2013-01-01

    The development of focusing optics based on wide band Laue lenses operating from ∼60 keV up to several hundreds of keV is particularly challenging. This type of hard X-ray or gamma ray optics requires a high performance focal plane detector in order to exploit to the best its intrinsic capabiliti...

  11. Hard X-ray dose intensity and spatial distribution in a plasma focus ...

    Indian Academy of Sciences (India)

    Hard X-rays; plasma focus; thermoluminescence dosimeter; argon gas; scintillator detector. PACS Nos 52.58.Lq; 52.59.Hq. 1. Introduction. Plasma focus (PF) devices are coaxial guns consisting of two cylindrical electrodes placed in a chamber filled with a few mbar of gas. These devices have been built with capacitor.

  12. Detections of hard X-ray emissions from bright early-type galaxies with ASCA

    Science.gov (United States)

    Matsushita, K.; Makishima, K.; Awaki, H.; Canizares, C. R.; Fabian, A. C.; Fukazawa, Y.; Loewenstein, M.; Matsumoto, H.; Mihara, T.; Mushotzky, R. F.

    1994-01-01

    Five bright elliptical galaxies in the Virgo Cluster, NGC 4365, NGC 4374 (M84), NGC 4406 (M86), NGC 4472 (M49), and NGC 4636, were observed with ASCA. In addition to the extended thermal X-ray emission of temperature kT approximately 1 keV, harder X-rays with color temperature kT greater than or equal to 2 keV were detected from all of them. The 2-10 keV luminosities of this hard component for the five galaxies, integrated within 5 min, are distributed within a relatively narrow range of (1-4) x 10(exp 40) ergs/s. The hard X-ray component is primarily attributed to the integrated emission from discrete X-ray sources. In NGC 4406 and NGC 4374 the data indicate that the hard component is contributed additionally by foreground/background emission from the hot intracluster medium (ICM) of the Virgo Cluster. The hard component of NGC 4472 seems also contributed by the Virgo ICM emission, but in this case there is evidence that the ICM brightness is locally enhanced within approximately 10 min of NGC 4472.

  13. The NuSTAR Hard X-Ray Survey of the Norma Arm Region

    DEFF Research Database (Denmark)

    Fornasini, Francesca M.; Tomsick, John A.; Hong, JaeSub

    2017-01-01

    We present a catalog of hard X-ray sources in a square-degree region surveyed by the Nuclear Spectroscopic Telescope Array (NuSTAR) in the direction of the Norma spiral arm. This survey has a total exposure time of 1.7 Ms, and the typical and maximum exposure depths are 50 ks and 1 Ms, respectively...

  14. Development of grazing incidence multilayer mirrors for hard X-ray focusing telescopes

    DEFF Research Database (Denmark)

    Mao, Peter H.; Harrison, Fiona A.; Platonov, Yuriy Y.

    1997-01-01

    We are developing depth-graded, multilayer-coated mirrors for astrophysical hard X-ray focusing telescopes. In this paper, we discuss the primary technical challenges associated with the multilayer coatings, and report on progress to date. We have sputtered constant d-spacing and depth-graded W/S...

  15. Atomic physics with hard X-rays from high brilliance synchrotron light sources

    Energy Technology Data Exchange (ETDEWEB)

    Southworth, S.; Gemmell, D.

    1996-08-01

    A century after the discovery of x rays, the experimental capability for studying atomic structure and dynamics with hard, bright synchrotron radiation is increasing remarkably. Tempting opportunities arise for experiments on many-body effects, aspects of fundamental photon-atom interaction processes, and relativistic and quantum-electrodynamic phenomena. Some of these possibilities are surveyed in general terms.

  16. Ultrafast Time-Resolved Hard X-Ray Emission Spectroscopy on a Tabletop

    Directory of Open Access Journals (Sweden)

    Luis Miaja-Avila

    2016-09-01

    Full Text Available Experimental tools capable of monitoring both atomic and electronic structure on ultrafast (femtosecond to picosecond time scales are needed for investigating photophysical processes fundamental to light harvesting, photocatalysis, energy and data storage, and optical display technologies. Time-resolved hard x-ray (>3  keV spectroscopies have proven valuable for these measurements due to their elemental specificity and sensitivity to geometric and electronic structures. Here, we present the first tabletop apparatus capable of performing time-resolved x-ray emission spectroscopy. The time resolution of the apparatus is better than 6 ps. By combining a compact laser-driven plasma source with a highly efficient array of microcalorimeter x-ray detectors, we are able to observe photoinduced spin changes in an archetypal polypyridyl iron complex [Fe(2,2^{′}-bipyridine_{3}]^{2+} and accurately measure the lifetime of the quintet spin state. Our results demonstrate that ultrafast hard x-ray emission spectroscopy is no longer confined to large facilities and now can be performed in conventional laboratories with 10 times better time resolution than at synchrotrons. Our results are enabled, in part, by a 100- to 1000-fold increase in x-ray collection efficiency compared to current techniques.

  17. The Hard X-ray Polarimeter X-Calibur - Astrophysical Motivation and Performance

    Science.gov (United States)

    Beilicke, Matthias; Baring, M. G.; Tueller, J.; Krawczynski, H.; Barthelmy, S. D.; Binns, W.; Buckley, J. H.; Cowsik, R.; Guo, Q.; Israel, M. H.; Kislat, F.; Matsumoto, H.; Okajima, T.; Schnittman, J.

    2013-04-01

    X-ray polarimetry promises to give qualitatively new information about high-energy sources, such as binary black hole systems, rotation and accretion powered neutron stars, microquasars, active galactic nuclei and gamma-ray bursts. We designed, built and tested a hard X-ray polarimeter X-Calibur to be flown in the focal plane of the InFOCuS grazing incidence hard X-ray telescope in fall 2013. The polarimeter combines a low-Z Compton scatterer with a high-Z Cadmium Zinc Telluride (CZT) detector assembly to measure the polarization of 20-80 keV X-rays. X-Calibur makes use of the fact that polarized photons Compton scatter preferentially perpendicular to the electric field orientation. In contrast to competing designs, which use only a small fraction of the incoming X-rays, X-Calibur achieves a high detection efficiency of order unity. We report on the technical design of X-Calibur, the X-Calibur and InFOCuS sensitivity on short and long duration balloon flights, and present detailed laboratory calibration measurements characterizing the performance of the instrument.

  18. In-Orbit Performance of the Hard X-Ray Detector on Borad Suzaku

    Energy Technology Data Exchange (ETDEWEB)

    Kokubun, Motohide; Makishima, Kazuo; Takahashi, Tadayuki; Murakami, Toshio; Tashiro, Makoto; Fukazawa, Yasushi; Kamae, Tuneyoshi; M.Madejski, Greg; Nakazawa, Kazuhiro; Yamaoka, Kazutaka; Terada, Yukikatsu; Yonetoku, Daisuke; Watanabe, Shin; Tamagawa, Toru; Mizuno, Tsunefumi; Kubota, Aya; Isobe, Naoki; Takahashi, Isao; Sato, Goro; Takahashi, Hiromitsu; Hong, Soojing; /Tokyo U. /Wako, RIKEN /JAXA, Sagamihara /Kanazawa U. /Saitama U. /Hiroshima U. /Aoyama Gakuin U. /Nihon U., Narashino /SLAC

    2007-10-26

    The in-orbit performance and calibration of the Hard X-ray Detector (HXD) on board the X-ray astronomy satellite Suzaku are described. Its basic performances, including a wide energy bandpass of 10-600 keV, energy resolutions of {approx}4 keV (FWHM) at 40 keV and {approx}11% at 511 keV, and a high background rejection efficiency, have been confirmed by extensive in-orbit calibrations. The long-term gains of PIN-Si diodes have been stable within 1% for half a year, and those of scintillators have decreased by 5-20%. The residual non-X-ray background of the HXD is the lowest among past non-imaging hard X-ray instruments in energy ranges of 15-70 and 150-500 keV. We provide accurate calibrations of energy responses, angular responses, timing accuracy of the HXD, and relative normalizations to the X-ray CCD cameras using multiple observations of the Crab Nebula.

  19. Femtosecond response of polyatomic molecules to ultra-intense hard X-rays

    Science.gov (United States)

    Rudenko, A.; Inhester, L.; Hanasaki, K.; Li, X.; Robatjazi, S. J.; Erk, B.; Boll, R.; Toyota, K.; Hao, Y.; Vendrell, O.; Bomme, C.; Savelyev, E.; Rudek, B.; Foucar, L.; Southworth, S. H.; Lehmann, C. S.; Kraessig, B.; Marchenko, T.; Simon, M.; Ueda, K.; Ferguson, K. R.; Bucher, M.; Gorkhover, T.; Carron, S.; Alonso-Mori, R.; Koglin, J. E.; Correa, J.; Williams, G. J.; Boutet, S.; Young, L.; Bostedt, C.; Son, S.-K.; Santra, R.; Rolles, D.

    2017-06-01

    X-ray free-electron lasers enable the investigation of the structure and dynamics of diverse systems, including atoms, molecules, nanocrystals and single bioparticles, under extreme conditions. Many imaging applications that target biological systems and complex materials use hard X-ray pulses with extremely high peak intensities (exceeding 1020 watts per square centimetre). However, fundamental investigations have focused mainly on the individual response of atoms and small molecules using soft X-rays with much lower intensities. Studies with intense X-ray pulses have shown that irradiated atoms reach a very high degree of ionization, owing to multiphoton absorption, which in a heteronuclear molecular system occurs predominantly locally on a heavy atom (provided that the absorption cross-section of the heavy atom is considerably larger than those of its neighbours) and is followed by efficient redistribution of the induced charge. In serial femtosecond crystallography of biological objects—an application of X-ray free-electron lasers that greatly enhances our ability to determine protein structure—the ionization of heavy atoms increases the local radiation damage that is seen in the diffraction patterns of these objects and has been suggested as a way of phasing the diffraction data. On the basis of experiments using either soft or less-intense hard X-rays, it is thought that the induced charge and associated radiation damage of atoms in polyatomic molecules can be inferred from the charge that is induced in an isolated atom under otherwise comparable irradiation conditions. Here we show that the femtosecond response of small polyatomic molecules that contain one heavy atom to ultra-intense (with intensities approaching 1020 watts per square centimetre), hard (with photon energies of 8.3 kiloelectronvolts) X-ray pulses is qualitatively different: our experimental and modelling results establish that, under these conditions, the ionization of a molecule is

  20. Fabrication of high-aspect-ratio hard x-ray zone plates with HSQ plating molds

    Science.gov (United States)

    Lu, Ming; Ocola, Leonidas E.; Divan, Ralu; Mancini, Derrick C.

    2008-08-01

    Fresnel zone plates are important x-ray diffractive optics which offer a focusing resolution approaching the theoretical limit. In hard x-ray region, the refractive indices of all the materials are close to unity, which requests thick zone plate to achieve a reasonable efficiency. It makes high-resolution zone plate extremely difficult to fabricate due to its high aspect ratio. We report a LIGA-like fabrication process employing e-beam resist HSQ as the plating mold material, which is relative simply compared with traditional processes. 1-μm-thick gold zone plates with 80-nm-wide outermost zone have been fabricated with this process.

  1. Multilayer coating facility for the HEFT hard x-ray telescope

    DEFF Research Database (Denmark)

    Cooper-Jensen, Carsten P.; Christensen, Finn Erland; Chen, Hubert

    2001-01-01

    A planar magnetron sputtering facility has been established at the Danish Space Research Institute (DSRI) for the production coating of depth graded multilayers on the thermally slumped glass segments which form the basis for the hard X-ray telescope on the HEFT balloon project. The facility...... is capable of coating 20-45 mirrors segments in each run. The coatings are optimized W/Si coatings. The paper describes the facility, the results of the calibration and presents data for the X-ray testing of flight mirrors....

  2. Hard X-ray nanotomography beamline 7C XNI at PLS-II.

    Science.gov (United States)

    Lim, Jun; Kim, Hyounggyu; Park, So Yeong

    2014-07-01

    The synchrotron-based hard X-ray nanotomography beamline, named 7C X-ray Nano Imaging (XNI), was recently established at Pohang Light Source II. This beamline was constructed primarily for full-field imaging of the inner structures of biological and material samples. The beamline normally provides 46 nm resolution for still images and 100 nm resolution for tomographic images, with a 40 µm field of view. Additionally, for large-scale application, it is capable of a 110 µm field of view with an intermediate resolution.

  3. All-Sky Hard X-Ray Spectral Line Survey with EXIST

    Science.gov (United States)

    Fishman, G. J.; Grindlay, J. E.; Hong, J.; Hartmann, D. H.; Vadawale, S.; Wilson-Hodge, C. A.

    2006-01-01

    The Energetic X-ray Imaging Survey Telescope (EXIST), under study to be the Black Hole Finder Probe in NASA's Beyond Einstein Program, would image the sky every 95 min in the energy range 10-600 keV. Although the main scientific objectives of EXIST are the systematic, all-sky survey of heavily obscured AGNs and gamma-ray bursts, there is a substantial capability of EXIST for the observation of transient and persistent hard X-ray lines from several astrophysical sources.

  4. Weak hard X-ray emission from two broad absorption line quasars observed with NuSTAR: Compton-thick absorption or intrinsic X-ray weakness?

    DEFF Research Database (Denmark)

    Luo, B.; Brandt, W. N.; Alexander, D. M.

    2013-01-01

    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 ≈ 400-600 hard X-ray (≳ 10 keV) photons with NuSTAR, provided that these photons...... are not significantly absorbed (NH ≲ 1024 cm-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...

  5. Two dimensional hard x-ray nanofocusing with crossed multilayer Laue lenses

    Science.gov (United States)

    Yan, Hanfei; Rose, Volker; Shu, Deming; Lima, Enju; Chol Kang, Hyon; Conley, Ray; Liu, Chian; Jahedi, Nima; Macrander, Albert T.; Stephenson, G. Brian; Holt, Martin; Chu, Yong S.; Lu, Ming; Maser, Jörg

    2011-08-01

    Hard x-ray microscopy with nanometer resolution will open frontiers in the study of materials and devices, environmental sciences, and life sciences by utilizing the unique characterization capabilities of x-rays. Here we report two-dimensional nanofocusing by multilayer Laue lenses (MLLs), a type of diffractive optics that is in principle capable of focusing x-rays to 1 nm. We demonstrate focusing to a 25 × 27 nm2 FWHM spot with an efficiency of 2% at a photon energy of 12 keV, and to a 25 × 40 nm2 FWHM spot with an efficiency of 17% at a photon energy of 19.5 keV.

  6. The Swift BAT Hard X-ray Survey - A New Window on the Local AGN Universe

    Science.gov (United States)

    Mushotzky, Richard

    2009-01-01

    The Swift Burst and Transient telescope (BAT) has surveyed the entire sky for the last 3.5 years obtaining the first sensitive all sky survey of the 14-195 keV sky. At high galactic latitudes the vast majority of the detected sources are AGN. Since hard x-rays penetrate all but Compton thick obscuring material (Column densities of 1.6E24 atms/cm2) this survey is unbiased with respect to obscuration, host galaxy type, optical , radio or IR properties. We will present results on the broad band x-ray properties, the nature of the host galaxies, the luminosity function and will discuss a few of the optical, IR and x-ray results in detail.

  7. Hard X-ray detection with a gallium phosphide Schottky diode

    Energy Technology Data Exchange (ETDEWEB)

    Owens, Alan [Science Payload and Advanced Concepts Office, ESA/ESTEC, Postbus 299, 2200AG Noordwijk (Netherlands)], E-mail: aowens@rssd.esa.int; Andersson, S.; Hartog, R. den; Quarati, F. [Science Payload and Advanced Concepts Office, ESA/ESTEC, Postbus 299, 2200AG Noordwijk (Netherlands); Webb, A.; Welter, E. [HASYLAB at DESY, Notkestrasse 85, D-22607 Hamburg (Germany)

    2007-11-01

    We report on the detection of hard X-rays using a GaP Schottky diode at the HASYLAB synchrotron radiation research facility. Exposure to alpha particles from an {sup 214}Am source showed that the device was spectroscopic at room temperature with a FWHM energy resolution of 3.5% at 5.5 MeV. It was also found to be responsive to X-rays in the range 11-100 keV. Although individual energies are not spectrally resolved there is a proportionality of response to increasing X-ray energy. A two-dimensional scan of the sensitive area using a 30x30 {mu}m{sup 2} 30 keV pencil beam showed the spatial response of the detector to be uniform at the few percent level, consistent with statistics.

  8. Nanofocusing of hard X-ray free electron laser pulses using diamond based Fresnel zone plates

    Science.gov (United States)

    David, C.; Gorelick, S.; Rutishauser, S.; Krzywinski, J.; Vila-Comamala, J.; Guzenko, V. A.; Bunk, O.; Färm, E.; Ritala, M.; Cammarata, M.; Fritz, D. M.; Barrett, R.; Samoylova, L.; Grünert, J.; Sinn, H.

    2011-08-01

    A growing number of X-ray sources based on the free-electron laser (XFEL) principle are presently under construction or have recently started operation. The intense, ultrashort pulses of these sources will enable new insights in many different fields of science. A key problem is to provide x-ray optical elements capable of collecting the largest possible fraction of the radiation and to focus into the smallest possible focus. As a key step towards this goal, we demonstrate here the first nanofocusing of hard XFEL pulses. We developed diamond based Fresnel zone plates capable of withstanding the full beam of the world's most powerful x-ray laser. Using an imprint technique, we measured the focal spot size, which was limited to 320 nm FWHM by the spectral band width of the source. A peak power density in the focal spot of 4×1017 W/cm2 was obtained at 70 fs pulse length.

  9. The Variable Crab Nebula: Evidence for a Connection between GeV flares and Hard X-ray Variations

    Science.gov (United States)

    Wilson-Hodge, Colleen A.; Kust Harding, Alice; Hays, Elizabeth A.; Cherry, Michael L.; Case, Gary L.; Finger, Mark H.; Jenke, Peter; Zhang, Xiao-Ling

    2016-04-01

    In 2010, hard X-ray variations (Wilson-Hodge et al. 2011) and GeV flares (Tavani et al 2011, Abdo et al. 2011) from the Crab Nebula were discovered. Connections between these two phenomena were unclear, in part because the timescales were quite different, with yearly variations in hard X-rays and hourly to daily variations in the GeV flares. The hard X-ray flux from the Crab Nebula has again declined since 2014, much like it did in 2008-2010. During both hard X-ray decline periods, the Fermi LAT detected no GeV flares, suggesting that injection of particles from the GeV flares produces the much slower and weaker hard X-ray variations. The timescale for the particles emitting the GeV flares to lose enough energy to emit synchrotron photons in hard X-rays is consistent with the yearly variations observed in hard X-rays and with the expectation that the timescale for variations slowly increases with decreasing energy. This hypothesis also predicts even slower and weaker variations below 10 keV, consistent with the non-detection of counterparts to the GeV flares by Chandra (Weisskopf et al 2013). We will present a comparison of the observed hard X-ray variations and a simple model of the decay of particles from the GeV flares to test our hypothesis.

  10. The Variable Crab Nebula: Evidence for a Connection Between GeV Flares and Hard X-ray Variations

    Science.gov (United States)

    Wilson-Hodge, Colleen A.; Harding, A. K.; Hays, E. A.; Cherry, M. L.; Case, G. L.; Finger, M. H.; Jenke, P.; Zhang, X.

    2016-01-01

    In 2010, hard X-ray variations (Wilson-Hodge et al. 2011) and GeV flares (Tavani et al 2011, Abdo et al. 2011) from the Crab Nebula were discovered. Connections between these two phenomena were unclear, in part because the timescales were quite different, with yearly variations in hard X-rays and hourly to daily variations in the GeV flares. The hard X-ray flux from the Crab Nebula has again declined since 2014, much like it did in 2008-2010. During both hard X-ray decline periods, the Fermi LAT detected no GeV flares, suggesting that injection of particles from the GeV flares produces the much slower and weaker hard X-ray variations. The timescale for the particles emitting the GeV flares to lose enough energy to emit synchrotron photons in hard X-rays is consistent with the yearly variations observed in hard X-rays and with the expectation that the timescale for variations slowly increases with decreasing energy. This hypothesis also predicts even slower and weaker variations below 10 keV, consistent with the non-detection of counterparts to the GeV flares by Chandra (Weisskopf et al 2013). We will present a comparison of the observed hard X-ray variations and a simple model of the decay of particles from the GeV flares to test our hypothesis.

  11. Broad-band characteristics of seven new hard X-ray selected cataclysmic variables

    Science.gov (United States)

    Bernardini, F.; de Martino, D.; Mukai, K.; Russell, D. M.; Falanga, M.; Masetti, N.; Ferrigno, C.; Israel, G.

    2017-10-01

    We present timing and spectral analysis of a sample of seven hard X-ray selected cataclysmic variable candidates based on simultaneous X-ray and optical observations collected with XMM-Newton, complemented with Swift/BAT and INTEGRAL /IBIS hard X-ray data and ground-based optical photometry. For six sources, X-ray pulsations are detected for the first time in the range of ˜296-6098 s, identifying them as members of the magnetic class. Swift J0927.7-6945, Swift J0958.0-4208, Swift J1701.3-4304, Swift J2113.5+5422 and possibly PBC J0801.2-4625 are intermediate polars (IPs), while Swift J0706.8+0325 is a short (1.7 h) orbital period polar, the 11th hard X-ray-selected identified so far. X-ray orbital modulation is also observed in Swift J0927.7-6945 (5.2 h) and Swift J2113.5+5422 (4.1 h). Swift J1701.3-4304 is discovered as the longest orbital period (12.8 h) deep eclipsing IP. The spectra of the magnetic systems reveal optically thin multitemperature emission between 0.2 and 60 keV. Energy-dependent spin pulses and the orbital modulation in Swift J0927.7-6945 and Swift J2113.5+5422 are due to intervening local high-density absorbing material (NH ˜ 1022 - 23 cm-2). In Swift J0958.0-4208 and Swift J1701.3-4304, a soft X-ray blackbody (kT ˜ 50 and ˜80 eV) is detected, adding them to the growing group of `soft' IPs. White dwarf masses are determined in the range of ˜ 0.58-1.18 M⊙, indicating massive accreting primaries in five of them. Most sources accrete at rates lower than the expected secular value for their orbital period. Formerly proposed as a long-period (9.4 h) nova-like CV, Swift J0746.3-1608 shows peculiar spectrum and light curves suggesting either an atypical low-luminosity CV or a low-mass X-ray binary.

  12. Possibilities and Challenges of Scanning Hard X-ray Spectro-microscopy Techniques in Material Sciences

    Directory of Open Access Journals (Sweden)

    Andrea Somogyi

    2015-06-01

    Full Text Available Scanning hard X-ray spectro-microscopic imaging opens unprecedented possibilities in the study of inhomogeneous samples at different length-scales. It gives insight into the spatial variation of the major and minor components, impurities and dopants of the sample, and their chemical and electronic states at micro- and nano-meter scales. Measuring, modelling and understanding novel properties of laterally confined structures are now attainable. The large penetration depth of hard X-rays (several keV to several 10 keV beam energy makes the study of layered and buried structures possible also in in situ and in operando conditions. The combination of different X-ray analytical techniques complementary to scanning spectro-microscopy, such as X-ray diffraction, X-ray excited optical luminescence, secondary ion mass spectrometry (SIMS and nano-SIMS, provides access to optical characteristics and strain and stress distributions. Complex sample environments (temperature, pressure, controlled atmosphere/vacuum, chemical environment are also possible and were demonstrated, and allow as well the combination with other analysis techniques (Raman spectroscopy, infrared imaging, mechanical tensile devices, etc. on precisely the very same area of the sample. The use of the coherence properties of X-rays from synchrotron sources is triggering emerging experimental imaging approaches with nanometer lateral resolution. New fast analytical possibilities pave the way towards statistically significant studies at multi- length-scales and three dimensional tomographic investigations. This paper gives an overview of these techniques and their recent achievements in the field of material sciences.

  13. Sub-micron Hard X-ray Fluorescence Imaging of Synthetic Elements

    Science.gov (United States)

    Jensen, Mark P.; Aryal, Baikuntha P.; Gorman-Lewis, Drew; Paunesku, Tatjana; Lai, Barry; Vogt, Stefan; Woloschak, Gayle E.

    2013-01-01

    Synchrotron-based X-ray fluorescence microscopy (SXFM) using hard X-rays focused into sub-micron spots is a powerful technique for elemental quantification and mapping, as well as microspectroscopic measurement such as μ-XANES (X-ray absorption near edge structure). We have used SXFM to image and simultaneously quantify the transuranic element plutonium at the L3 or L2 edge as well as lighter biologically essential elements in individual rat pheochromocytoma (PC12) cells after exposure to the long-lived plutonium isotope 242Pu. Elemental maps reveal that plutonium localizes principally in the cytoplasm of the cells and avoids the cell nucleus, which is marked by the highest concentrations of phosphorus and zinc, under the conditions of our experiments. The minimum detection limit under typical acquisition conditions for an average 202 μm2 cell is 1.4 fg Pu/cell or 2.9 × 10−20 moles Pu/μm2, which is similar to the detection limit of K-edge SXFM of transition metals at 10 keV. Copper electron microscopy grids were used to avoid interference from gold X-ray emissions, but traces of strontium present in naturally occurring calcium can still interfere with plutonium detection using its Lα X-ray emission. PMID:22444530

  14. Staring/focusing lobster-eye hard x-ray imaging for non-astronomical objects

    Science.gov (United States)

    Gertsenshteyn, Michael; Jannson, Tomasz; Savant, Gajendra

    2005-08-01

    A new approach to hard X-ray imaging is proposed, based on staring optics consisting of a lobster-eye lens. This new Staring Imaging Lobster-Eye X-Ray approach is especially suited to X-ray lobster-eye imaging of non-astronomical objects at finite distances, because the staring optics replacing the standard scanning optics, result in an extremely efficient power budget, making possible not only the use of low-efficiency Compton backscattering but also operation with low-flux X-ray beams, increasing operator safety. The lobster-eye optics, consisting of square-cross-section microchannels, transmit an X-ray beam by total external reflection. This mode of operation has already been verified for viewing astronomical objects. Its major challenge is minimizing image defocusing by apodization. For this purpose, a new lens imaging equation is derived, and a new local optical axis concept is defined. Applications include medical imaging, cargo inspection, non-destructive testing, industrial and security safeguards, and surveillance.

  15. Communication: The electronic structure of matter probed with a single femtosecond hard x-ray pulse

    Directory of Open Access Journals (Sweden)

    J. Szlachetko

    2014-03-01

    Full Text Available Physical, biological, and chemical transformations are initiated by changes in the electronic configuration of the species involved. These electronic changes occur on the timescales of attoseconds (10−18 s to femtoseconds (10−15 s and drive all subsequent electronic reorganization as the system moves to a new equilibrium or quasi-equilibrium state. The ability to detect the dynamics of these electronic changes is crucial for understanding the potential energy surfaces upon which chemical and biological reactions take place. Here, we report on the determination of the electronic structure of matter using a single self-seeded femtosecond x-ray pulse from the Linac Coherent Light Source hard x-ray free electron laser. By measuring the high energy resolution off-resonant spectrum (HEROS, we were able to obtain information about the electronic density of states with a single femtosecond x-ray pulse. We show that the unoccupied electronic states of the scattering atom may be determined on a shot-to-shot basis and that the measured spectral shape is independent of the large intensity fluctuations of the incoming x-ray beam. Moreover, we demonstrate the chemical sensitivity and single-shot capability and limitations of HEROS, which enables the technique to track the electronic structural dynamics in matter on femtosecond time scales, making it an ideal probe technique for time-resolved X-ray experiments.

  16. Hybrid setup for micro- and nano-computed tomography in the hard X-ray range

    Science.gov (United States)

    Fella, Christian; Balles, Andreas; Hanke, Randolf; Last, Arndt; Zabler, Simon

    2017-12-01

    With increasing miniaturization in industry and medical technology, non-destructive testing techniques are an area of ever-increasing importance. In this framework, X-ray microscopy offers an efficient tool for the analysis, understanding, and quality assurance of microscopic samples, in particular as it allows reconstructing three-dimensional data sets of the whole sample's volume via computed tomography (CT). The following article describes a compact X-ray microscope in the hard X-ray regime around 9 keV, based on a highly brilliant liquid-metal-jet source. In comparison to commercially available instruments, it is a hybrid that works in two different modes. The first one is a micro-CT mode without optics, which uses a high-resolution detector to allow scans of samples in the millimeter range with a resolution of 1 μm. The second mode is a microscope, which contains an X-ray optical element to magnify the sample and allows resolving 150 nm features. Changing between the modes is possible without moving the sample. Thus, the instrument represents an important step towards establishing high-resolution laboratory-based multi-mode X-ray microscopy as a standard investigation method.

  17. The multi-purpose hard X-ray beamline BL10 at the DELTA storage ring.

    Science.gov (United States)

    Lützenkirchen-Hecht, D; Wagner, R; Szillat, S; Hüsecken, A K; Istomin, K; Pietsch, U; Frahm, Ronald

    2014-07-01

    The layout and the characteristics of the hard X-ray beamline BL10 at the superconducting asymmetric wiggler at the 1.5 GeV Dortmund Electron Accelerator DELTA are described. This beamline is equipped with a Si(111) channel-cut monochromator and is dedicated to X-ray studies in the spectral range from ∼4 keV to ∼16 keV photon energy. There are two different endstations available. While X-ray absorption studies in different detection modes (transmission, fluorescence, reflectivity) can be performed on a designated table, a six-axis kappa diffractometer is installed for X-ray scattering and reflectivity experiments. Different detector set-ups are integrated into the beamline control software, i.e. gas-filled ionization chambers, different photodiodes, as well as a Pilatus 2D-detector are permanently available. The performance of the beamline is illustrated by high-quality X-ray absorption spectra from several reference compounds. First applications include temperature-dependent EXAFS experiments from liquid-nitrogen temperature in a bath cryostat up to ∼660 K by using a dedicated furnace. Besides transmission measurements, fluorescence detection for dilute sample systems as well as surface-sensitive reflection-mode experiments are presented.

  18. Hard X-ray photoelectron and X-ray absorption spectroscopy characterization of oxidized surfaces of iron sulfides

    Energy Technology Data Exchange (ETDEWEB)

    Mikhlin, Yuri, E-mail: yumikh@icct.ru [Institute of Chemistry and Chemical Technology of the Siberian Branch of the Russian Academy of sciences, Akademgorodok, 50/24, Krasnoyarsk, 660036 (Russian Federation); Tomashevich, Yevgeny [Institute of Chemistry and Chemical Technology of the Siberian Branch of the Russian Academy of sciences, Akademgorodok, 50/24, Krasnoyarsk, 660036 (Russian Federation); Vorobyev, Sergey [Institute of Chemistry and Chemical Technology of the Siberian Branch of the Russian Academy of sciences, Akademgorodok, 50/24, Krasnoyarsk, 660036 (Russian Federation); Siberian Federal University, Svobodny pr. 79, Krasnoyarsk, 660041 (Russian Federation); Saikova, Svetlana [Siberian Federal University, Svobodny pr. 79, Krasnoyarsk, 660041 (Russian Federation); Romanchenko, Alexander [Institute of Chemistry and Chemical Technology of the Siberian Branch of the Russian Academy of sciences, Akademgorodok, 50/24, Krasnoyarsk, 660036 (Russian Federation); Félix, Roberto [Renewable Energy, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Lise-Meitner-Campus, Hahn-Meitner-Platz 1, 14109 Berlin (Germany)

    2016-11-30

    Highlights: • Pyrite and pyrrhotite in-air abraded and etched in aqueous Fe{sup 3+} solution were studied. • HAXPES (2 keV-6 keV) and Fe K-, S K-edge XANES (TEY and PFY mode) were measured. • Outer “polysulfide”, strongly S-excessive layers are no more than 1–4 nm thick. • “Metal-depleted” layers depend on the treatment and differ for pyrite and pyrrhotite. • Extended nearly-stoichiometric “defective” underlayers were detected using TEY XANES. - Abstract: Hard X-ray photoelectron spectroscopy (HAXPES) using an excitation energy range of 2 keV to 6 keV in combination with Fe K- and S K-edge XANES, measured simultaneously in total electron (TEY) and partial fluorescence yield (PFY) modes, have been applied to study near-surface regions of natural polycrystalline pyrite FeS{sub 2} and pyrrhotite Fe{sub 1−x}S before and after etching treatments in an acidic ferric chloride solution. It was found that the following near-surface regions are formed owing to the preferential release of iron from oxidized metal sulfide lattices: (i) a thin, no more than 1–4 nm in depth, outer layer containing polysulfide species, (ii) a layer exhibiting less pronounced stoichiometry deviations and low, if any, concentrations of polysulfide, the composition and dimensions of which vary for pyrite and pyrrhotite and depend on the chemical treatment, and (iii) an extended almost stoichiometric underlayer yielding modified TEY XANES spectra, probably, due to a higher content of defects. We suggest that the extended layered structure should heavily affect the near-surface electronic properties, and processes involving the surface and interfacial charge transfer.

  19. Resonantly excited betatron hard X-Rays from Ionization Injected Electron Beam in a Laser Plasma Accelerator

    CERN Document Server

    Huang, K; Li, Y F; Li, D Z; Tao, M Z; Mirzaie, M; Ma, Y; Zhao, J R; Li, M H; Chen, M; Hafz, N; Sokollik, T; Sheng, Z M; Zhang, J

    2015-01-01

    A new scheme for bright hard x-ray emission from laser wakefield electron accelerator is reported, where pure nitrogen gas is adopted. Intense Betatron x-ray beams are generated from ionization injected K-shell electrons of nitrogen into the accelerating wave bucket. The x-ray radiation shows synchrotron-like spectrum with total photon yield 8$\\times$10$^8$/shot and $10^8$ over 110keV. In particular, the betatron hard x-ray photon yield is 10 times higher compared to the case of helium gas under the same laser parameters. Particle-in-cell simulation suggests that the enhancement of the x-ray yield results from ionization injection, which enables the electrons to be quickly accelerated to the driving laser region for subsequent betatron resonance. Employing the present scheme,the single stage nitrogen gas target could be used to generate stable high brightness betatron hard x-ray beams.

  20. A Preliminary Research on the Development of the Hard X-ray Imaging Telescope

    Science.gov (United States)

    Zheng, Chun-Xiao; Cai, Ming-Sheng; Hu, Yi-Ming; Huang, Yong-Yi; Gong, Yi-Zhong

    2014-10-01

    The hard X-ray imaging telescope based on the Fourier transform imaging technique is introduced. The double-layer parallel gratings are used to make the modulation and coding on the light emerging from a celestial X-ray source, the modulated light is acquired, to make the optoelectronic conversion by scintillation crystal detectors, and finally read out by the electronic system. The modulation collimator X-ray telescopes can be divided into two types: the spatial modulation and temporal modulation. The temporal modulation system requires the scanning motion of the detector system, but the spatial modulation system requires no motion. The technology of grating fabrication is investigated, and the basic structure design of the collimators is given. The principal compo- nents of the prototype hard X-ray imaging telescope of spatial modulation type are successfully developed, including the 8 CsI crystal detector modules (contain- ing photomultipliers or PMTs), 8-channel shaping amplifiers (two of them are prepared for experiments), and the data acquisition system. And the preliminary test results of the electronic system are also given.

  1. Design and development of the multilayer optics for the new hard x-ray mission

    Science.gov (United States)

    Pareschi, G.; Basso, S.; Citterio, O.; Spiga, D.; Tagliaferri, G.; Civitani, M.; Raimondi, L.; Sironi, G.; Cotroneo, V.; Negri, B.; Parodi, Giancarlo; Martelli, F.; Borghi, G.; Orlandi, A.; Vernani, D.; Valsecchi, G.; Binda, R.; Romaine, S.; Gorenstein, P.; Attinà, P.

    2017-11-01

    The New Hard X-ray Mission (NHXM) project will be operated by 2017 and is currently undergoing a Phase B study, under the coordination of the Italian Space Agency (ASI). The project is being proposed by an international team in the context of the ESA Call CV M3 as a Small Mission program, with a large Italian participation. It is based on 4 hard X-ray optics modules, each formed by 60 evenly spaced multilayer coated Wolter I mirror shells. An extensible bench is used to reach the 10 m focal length. The Wolter I monolithic substrates with multilayer coating are produced in NiCo by electroforming replication. Three of the mirror modules will host in the focal plane a hybrid a detector system (a soft X-ray Si DEPFET array plus a high energy CdTe detector). The detector of the fourth telescope will be a photoelectric polarimeter with imaging capabilities, operating from 2 up to 35 keV. The total on axis effective area of the three telescopes at 1 keV and 30 kev is of 1500 cm2 and 350 cm2 respectively, with an angular resolution of 20 arcsec HEW at 30 keV. In this paper we report on the design and development of the multilayer coated X-ray mirrors based on NiCo shells.

  2. The Hitomi (ASTRO-H) hard x-ray telescope (HXT): current status of calibration

    Science.gov (United States)

    Awaki, Hisamitsu; Matsumoto, Hironori; Ishida, Manabu; Furuzawa, Akihiro; Yamauchi, Shigeo; Maeda, Yoshitomo; Kunieda, Hideyo; Haba, Yoshito; Hayashi, Takayuki; Iizuka, Ryo; Ishibashi, Kazunori; Mitsuishi, Ikuyuki; Miyazawa, Takuya; Mori, Hideyuki; Okajima, Takashi; Sugita, Satoshi; Tamura, Keisuke; Tawara, Yuzuru; Yoshida, Tessei

    2017-08-01

    The Japanese X-ray Astronomy Satellite, Hitomi (ASTRO-H) carried two hard X-ray telescopes (HXT), covering the energy band from 5 keV to 80 keV. In the initial functional verification phase of the onboard instruments, G21.5-0.9 and Crab nebula were observed with HXT. The data of G21.5-0.9 observation indicated that the hard X-ray imaging system worked well. Detail calibration of the Hitomi HXTs was performed with the observation data of Crab nebula. We extracted X-ray images of the Crab pulsar excluding the nebular emission, and confirmed that the imaging performance in orbit was satisfied with the requirement of the HXT. The 8-80 keV Crab spectrum was well fitted with a power-law model with the absorbed column of NH=3×1021 cm-2 . The estimated photon index of 2.122+/-0.003 was consistent with previous results of Crab observation, while the observed 2-10 keV flux of 2.3×10-8 erg s-1 cm-2 was slightly larger than the previous observation. We note that there was discrepancy between the simulated and the measured effective area on ground. Thus, we introduced a fudge factor to reproduce the effective area obtained in the ground calibration. The fudge factor of HXTs are included in the latest calibration database of Hitomi.

  3. Hard x-ray telescopes to be onboard ASTRO-H.

    Science.gov (United States)

    Awaki, Hisamitsu; Kunieda, Hideyo; Ishida, Manabu; Matsumoto, Hironori; Babazaki, Yasunori; Demoto, Tadatsugu; Furuzawa, Akihiro; Haba, Yoshito; Hayashi, Takayuki; Iizuka, Ryo; Ishibashi, Kazunori; Ishida, Naoki; Itoh, Masayuki; Iwase, Toshihiro; Kosaka, Tatsuro; Kurihara, Daichi; Kuroda, Yuuji; Maeda, Yoshitomo; Meshino, Yoshifumi; Mitsuishi, Ikuyuki; Miyata, Yuusuke; Miyazawa, Takuya; Mori, Hideyuki; Nagano, Housei; Namba, Yoshiharu; Ogasaka, Yasushi; Ogi, Keiji; Okajima, Takashi; Saji, Shigetaka; Shimasaki, Fumiya; Sato, Takuro; Sato, Toshiki; Sugita, Satoshi; Suzuki, Yoshio; Tachibana, Kenji; Tachibana, Sasagu; Takizawa, Shunya; Tamura, Keisuke; Tawara, Yuzuru; Torii, Tatsuharu; Uesugi, Kentato; Yamashita, Koujun; Yamauchi, Shigeo

    2014-11-10

    The new Japanese x-ray astronomy satellite, ASTRO-H, will carry two identical hard x-ray telescopes (HXTs), which cover the energy range of 5 to 80 keV. The HXT mirrors employ tightly nested, conically approximated thin-foil Wolter-I optics, and the mirror surfaces are coated with Pt/C depth-graded multilayers to enhance the hard x-ray effective area by means of Bragg reflection. The HXT comprises foils 120-450 mm in diameter and 200 mm in length, with a focal length of 12 m. To obtain a large effective area, 213 aluminum foils 0.2 mm in thickness are tightly nested confocally. The requirements for HXT are a total effective area of >300  cm2 at 30 keV and an angular resolution of ' in half-power diameter (HPD). Fabrication of two HXTs has been completed, and the x-ray performance of each HXT was measured at a synchrotron radiation facility, SPring-8 BL20B2 in Japan. Angular resolutions (HPD) of 1.9' and 1.8' at 30 keV were obtained for the full telescopes of HXT-1 and HXT-2, respectively. The total effective area of the two HXTs at 30 keV is 349  cm2.

  4. HERO: A Balloon-Borne Hard-X-Ray Focusing Telescope

    Science.gov (United States)

    Ramsey, Brian

    2008-01-01

    HERO, for High Energy Replicated Optics, is an evolutionary balloon payload featuring hard-x-ray grazing-incidence nickel optics. The HERO payload is designed to perform high-sensitivity, fine spatial resolution observations of galactic and extragalactic sources in an energy range that is as yet unexplored with grazing-incidence optics. A proof-of-concept flight with just 6 x-ray mirrors was completed in 2001 and captured the first focused hard-x-ray images galactic sources. Since that time, the payload has been greatly expanded and now features 100, in-house-fabricated mirror shells with an attendant large increase in sensitivity. In its current form, HERO was flown in 2007, from Fort Sumner, NM, and is schedules to fly again in September 2009, from Alice Springs, NT. Full details of the HERO payload will be provided in this presentation together with a discussion of the challenges of flying moderate resolution x-ray optics from a balloon platform.

  5. Theoretical modeling of Comptonized X-ray spectra of super-Eddington accretion flow: Origin of hard excess in ultraluminous X-ray sources

    Science.gov (United States)

    Kitaki, Takaaki; Mineshige, Shin; Ohsuga, Ken; Kawashima, Tomohisa

    2017-12-01

    X-ray continuum spectra of super-Eddington accretion flow are studied by means of Monte Carlo radiative transfer simulations based on the radiation hydrodynamic simulation data, in which both thermal- and bulk-Compton scatterings are taken into account. We compare the calculated spectra of accretion flow around black holes with masses of MBH = 10, 102, 103, and 104 M⊙ for a fixed mass injection rate (from the computational boundary at 103 rs) of 103 LEdd/c2 (with rs, LEdd, and c being the Schwarzschild radius, the Eddington luminosity, and the speed of light, respectively). The soft X-ray spectra exhibit mass dependence in accordance with the standard-disk relation; the maximum surface temperature is scaled as T ∝ M_{ BH}^{ -1/4}. The spectra in the hard X-ray band, by contrast with soft X-ray, look to be quite similar among different models, if we normalize the radiation luminosity by MBH. This reflects that the hard component is created by thermal- and bulk-Compton scatterings of soft photons originating from an accretion flow in the overheated and/or funnel regions, the temperatures of which have no dependence on mass. The hard X-ray spectra can be reproduced by a Wien spectrum with the temperature of T ˜ 3 keV accompanied by a hard excess at photon energy above several keV. The excess spectrum can be fitted well with a power law with a photon index of Γ ˜ 3. This feature is in good agreement with that of the recent NuSTAR observations of ULXs (ultra-luminous X-ray sources).

  6. First hard X-ray detection and broad-band X-ray study of the unidentified transient AX J1949.8+2534

    Science.gov (United States)

    Sguera, V.; Sidoli, L.; Paizis, A.; Masetti, N.; Bird, A. J.; Bazzano, A.

    2017-08-01

    We present the results from INTEGRAL and Swift/XRT observations of the hitherto poorly studied unidentified X-ray transient AX J1949.8+2534, and on archival multiwavelength observations of field objects. Bright hard X-ray outbursts have been discovered above 20 keV for the first time, the measured duty cycle and dynamic range are of the order of ˜4 per cent and ≥ 630, respectively. The source was also detected during a low soft X-ray state (˜2 × 10-12 erg cm-2 s-1) thanks to a Swift/XRT followup, which allowed for the first time to perform a soft X-ray spectral analysis as well as significantly improve the source positional uncertainty from arcminute to arcsecond size. From archival near-infrared data, we pinpointed two bright objects as most likely counterparts whose photometric properties are compatible with an early-type spectral nature. This strongly supports a high-mass X-ray binary (HMXB) scenario for AX J1949.8+2534, specifically a Supergiant Fast X-ray Transient (more likely) or alternatively a Be HMXB.

  7. Diagnostics of underwater electrical wire explosion through a time- and space-resolved hard x-ray source.

    Science.gov (United States)

    Sheftman, D; Shafer, D; Efimov, S; Gruzinsky, K; Gleizer, S; Krasik, Ya E

    2012-10-01

    A time- and space-resolved hard x-ray source was developed as a diagnostic tool for imaging underwater exploding wires. A ~4 ns width pulse of hard x-rays with energies of up to 100 keV was obtained from the discharge in a vacuum diode consisting of point-shaped tungsten electrodes. To improve contrast and image quality, an external pulsed magnetic field produced by Helmholtz coils was used. High resolution x-ray images of an underwater exploding wire were obtained using a sensitive x-ray CCD detector, and were compared to optical fast framing images. Future developments and application of this diagnostic technique are discussed.

  8. A practical method to generate brilliant hard x-rays with a tabletop electron storage ring

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, H. [Ritsumeikan Univ., Shiga (Japan); Amano, D.; Miyade, H. [Sumitomo Heavy Industries, Ltd., Tanashi-City (Japan)

    1995-12-31

    With electron storage rings not only synchrotron radiation(SR) but also bremsstrahlung(BS) from a thin target placed in the electron orbit are mechanisms to generate brilliant x-ray beams. The calculated brilliance of BS with a 50 MeV storage ring, which is nearly 10{sup 13} photons/s, mrad{sup 2}, mm{sup 2}, 0.1% band width for 100 keV x-rays, exceeds that of SR from a 1 GeV storage ring. This photon energy spectrum is almost constant and extend up to the electron energy. The reasons for this high brilliance with this new radiation scheme is that the electron beams penetrating the thin target are utilized repeatedly, the narrow angular divergence of BS is determined by the kinematics of relativistic electron as same as SR, and the x-ray source size of the order of 1 {mu}m is determined by the size of thin target instead of electron beam sizes. Continuous injection of electron beam to the storage ring at full energy is the way to keep high and constant beam current. Peak current and repetition rate determine x-ray out put power. Note that the power of x-ray beam is also provided from a RF cavity of the storage ring. In this paper we will report some experimental results and discuss further application on a coherent bremsstrahlung generated from a set of stacked foils placed in the electron orbit of the ring. Resulting from these investigations the photon storage ring which is based on a 50 MeV exact circular electron storage ring could provide wide range of coherent and incoherent radiations from far infrared to hard x-ray in a practical amount of radiation power.

  9. Pushing the limits: an instrument for hard X-ray imaging below 20 nm.

    Science.gov (United States)

    Nazaretski, E; Lauer, K; Yan, H; Bouet, N; Zhou, J; Conley, R; Huang, X; Xu, W; Lu, M; Gofron, K; Kalbfleisch, S; Wagner, U; Rau, C; Chu, Y S

    2015-03-01

    Hard X-ray microscopy is a prominent tool suitable for nanoscale-resolution non-destructive imaging of various materials used in different areas of science and technology. With an ongoing effort to push the 2D/3D imaging resolution down to 10 nm in the hard X-ray regime, both the fabrication of nano-focusing optics and the stability of the microscope using those optics become extremely challenging. In this work a microscopy system designed and constructed to accommodate multilayer Laue lenses as nanofocusing optics is presented. The developed apparatus has been thoroughly characterized in terms of resolution and stability followed by imaging experiments at a synchrotron facility. Drift rates of ∼2 nm h(-1) accompanied by 13 nm × 33 nm imaging resolution at 11.8 keV are reported.

  10. Resolving the hard X-ray emission of GX 5-1 with INTEGRAL

    DEFF Research Database (Denmark)

    Paizis, A.; Ebisawa, K.; Tikkanen, T.

    2005-01-01

    contamination from the nearby black hole candidate GRS 1758-258 above 20 keV. During our observations, GX 5-1 was mostly found in the horizontal and normal branch of its hardness intensity diagram. A clear hard X-ray emission is observed above similar to 30 keV which exceeds the exponential cut-off spectrum......We present the study of one year of INTEGRAL data on the neutron star low mass X-ray binary GX 5-1. Thanks to the excellent angular resolution and sensitivity of INTEGRAL, we are able to obtain a high quality spectrum of GX 5-1 from similar to 5keV to similar to 100 keV, for the first time without...

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

    Science.gov (United States)

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

    2013-05-01

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

  12. A new hard X-ray transient discovered by INTEGRAL: IGR J17559-2612

    DEFF Research Database (Denmark)

    Esposito, V.; Ferrigno, C.; Bozzo, E.

    2012-01-01

    INTEGRAL discovered a new hard X-ray transient, IGR J17559-2612, during the Galactic center observations performed from 2012-08-14 00:02:14 to 2012-08-14 14:45:54 UTC. The source is detected in the IBIS/ISGRI mosaic at a significance level of 8 σ (observation good time: 50 ks) both in the 20-40 k...

  13. Machine learning from hard x-ray surveys: applications to magnetic cataclysmic variable studies

    Science.gov (United States)

    Scaringi, Simone

    2009-11-01

    Within this thesis are discussed two main topics of contemporary astrophysics. The first is that of machine learning algorithms for astronomy whilst the second is that of magnetic cataclysmic variables (mCVs). To begin, an overview is given of ISINA: INTEGRAL Scouce Identifiction Network Algorithm. This machine learning algorithm, using random forests, is applied to the IBIS/ISGRI data set in order to ease the production of unbiased future soft gamma-ray source catalogues. The feature extraction process on an initial candidate list is described together with feature merging. Three trainng and testing sets are created in order to deal with the diverse time-scales encountered when dealing with the gamma-ray sky: one dealing with faint persistent source recognition, one dealing with strong persistent sources and a final one dealing with transients. For the latter, a new transient detection technique is introduced and described: the transient matrix. Finally the performance of the network is assessed and discussed using the testing set and some illustrative source examples. ISINA is also compared to the more conventional approach of visual inspection. Next mCVs are discussed, and in particular the properties arising from a hard X-ray selected sample which has proven remarkably efficient in detecting intermediate polars and asynchronous polars, two of the rarest type of cataclysmic variables (CVs). This thesis focuses particularly on the link between hard X-ray properties and spin/orbital periods. To this end, a new sample of these objects is constructed by cross-corelating candidate sources detected in INTEGRAL/IBIS observations against catalogues of known CVs. Also included in the analysis are hard X-ray Observations from Swift/BAT and SUZAKU/HXD in order to make the study more complete. It is found that most hard X-ray detected mCVs have Pspin/Porbattention is given to the very low number of detected systems in any ban between Pspin/Porb = 0.3 and Pspin/Porb = 1 and

  14. Eta Carinae's Hard X-ray Tail Measured with XMM-Newton and NuSTAR

    Science.gov (United States)

    Hamaguchi, Kenji; Corcoran, Michael F.; Sharma, Neetika; Gull, Theodore R.; Takahashi, Hiromitsu; Grefenstette, Brian; Yuasa, Takayuki; Stuhlinger, Martin; Russell, Christopher Michael Post; Moffat, Anthony F. J.; Madura, Thomas; Richardson, Noel; Groh, Jose; Pittard, Julian; Owocki, Stan

    2016-04-01

    Massive binary stellar systems drive shock plasma heating via the collision of winds from two stars (wind-wind collision: WWC). With typical (pre-shock) wind speeds of ≥1000 km s-1, temperatures can reach as high as several tens of millions of Kelvin. X-ray emission from these stable shocks provides important tests of shock physics. While the spectrum below 10 keV is complicated by discrete line emission and absorption components, the X-ray spectrum above 10 keV is relatively simple. This high-energy emission therefore provides important clues on the condition of the maximum thermalized plasma where the winds collide head-on, while also providing important information about particle acceleration through the shock.We obtained two coordinated X-ray observations of the super massive binary system η Carinae with XMM-Newton and NuSTAR, during the elevated X-ray flux state and just before the X-ray minimum flux state around the periastron passage in the summer of 2014. These NuSTAR observations clearly detected X-ray emission associated with η Car extending up to ~50 keV for the first time. The NuSTAR spectrum above 10 keV can be fit with the bremsstrahlung tail from a kT ~6 keV plasma, about 2 keV higher than those measured from the iron K emission line complex. This result may suggest that the companion star's pre-shock wind velocity is underestimated. The NuSTAR observation near the X-ray minimum state showed a gradual decline in the >5 keV emission by 40% in a day. The extreme absorption to the hardest emission component (NH~1e24 cm-2) suggests increased obscuration of the WWC X-ray emission by the thick primary stellar wind prior to superior conjunction. Neither observation detected the power-law component in the extremely hard band that INTEGRAL and Suzaku observed prior to 2011. If the non-detection by NuSTAR is caused by absorption, the power-law source must be small and located very near the WWC apex. Alternatively, it may be that the power-law source is not

  15. The first multi-wavelength campaign of AXP 4U 0142+61 from radio to hard X-rays

    NARCIS (Netherlands)

    den Hartog, P.R.; Kuiper, L.; Hermsen, W.; Rea, N.; Durant, M.; Stappers, B.; Kaspi, V.M.; Dib, R.

    2007-01-01

    For the first time a quasi-simultaneous multi-wavelength campaign has been performed on an Anomalous X-ray Pulsar from the radio to the hard X-ray band. 4U 0142+61 was an INTEGRAL target for 1 Ms in July 2005. During these observations it was also observed in the X-ray band with Swift and RXTE, in

  16. The GALAXIES beamline at the SOLEIL synchrotron: inelastic X-ray scattering and photoelectron spectroscopy in the hard X-ray range.

    Science.gov (United States)

    Rueff, J P; Ablett, J M; Céolin, D; Prieur, D; Moreno, Th; Balédent, V; Lassalle-Kaiser, B; Rault, J E; Simon, M; Shukla, A

    2015-01-01

    The GALAXIES beamline at the SOLEIL synchrotron is dedicated to inelastic X-ray scattering (IXS) and photoelectron spectroscopy (HAXPES) in the 2.3-12 keV hard X-ray range. These two techniques offer powerful complementary methods of characterization of materials with bulk sensitivity, chemical and orbital selectivity, resonant enhancement and high resolving power. After a description of the beamline components and endstations, the beamline capabilities are demonstrated through a selection of recent works both in the solid and gas phases and using either IXS or HAXPES approaches. Prospects for studies on liquids are discussed.

  17. Hard X-Ray Emission from Partially Occulted Solar Flares: RHESSI Observations in Two Solar Cycles

    Science.gov (United States)

    Effenberger, Frederic; Rubio da Costa, Fatima; Oka, Mitsuo; Saint-Hilaire, Pascal; Liu, Wei; Petrosian, Vahé; Glesener, Lindsay; Krucker, Säm

    2017-02-01

    Flares close to the solar limb, where the footpoints are occulted, can reveal the spectrum and structure of the coronal looptop source in X-rays. We aim at studying the properties of the corresponding energetic electrons near their acceleration site, without footpoint contamination. To this end, a statistical study of partially occulted flares observed with Reuven Ramaty High-Energy Solar Spectroscopic Imager is presented here, covering a large part of solar cycles 23 and 24. We perform detailed spectra, imaging, and light curve analyses for 116 flares and include contextual observations from SDO and STEREO when available, providing further insights into flare emission that were previously not accessible. We find that most spectra are fitted well with a thermal component plus a broken power-law, non-thermal component. A thin-target kappa distribution model gives satisfactory fits after the addition of a thermal component. X-ray imaging reveals small spatial separation between the thermal and non-thermal components, except for a few flares with a richer coronal source structure. A comprehensive light curve analysis shows a very good correlation between the derivative of the soft X-ray flux (from GOES) and the hard X-rays for a substantial number of flares, indicative of the Neupert effect. The results confirm that non-thermal particles are accelerated in the corona and estimated timescales support the validity of a thin-target scenario with similar magnitudes of thermal and non-thermal energy fluxes.

  18. Ultra-high aspect ratio high-resolution nanofabrication for hard X-ray diffractive optics

    Science.gov (United States)

    Chang, Chieh; Sakdinawat, Anne

    2014-06-01

    Although diffractive optics have played a major role in nanoscale soft X-ray imaging, high-resolution and high-efficiency diffractive optics have largely been unavailable for hard X-rays where many scientific, technological and biomedical applications exist. This is owing to the long-standing challenge of fabricating ultra-high aspect ratio high-resolution dense nanostructures. Here we report significant progress in ultra-high aspect ratio nanofabrication of high-resolution, dense silicon nanostructures using vertical directionality controlled metal-assisted chemical etching. The resulting structures have very smooth sidewalls and can be used to pattern arbitrary features, not limited to linear or circular. We focus on the application of X-ray zone plate fabrication for high-efficiency, high-resolution diffractive optics, and demonstrate the process with linear, circular, and spiral zone plates. X-ray measurements demonstrate high efficiency in the critical outer layers. This method has broad applications including patterning for thermoelectric materials, battery anodes and sensors among others.

  19. Resonantly Enhanced Betatron Hard X-rays from Ionization Injected Electrons in a Laser Plasma Accelerator

    Science.gov (United States)

    Huang, K.; Li, Y. F.; Li, D. Z.; Chen, L. M.; Tao, M. Z.; Ma, Y.; Zhao, J. R.; Li, M. H.; Chen, M.; Mirzaie, M.; Hafz, N.; Sokollik, T.; Sheng, Z. M.; Zhang, J.

    2016-01-01

    Ultrafast betatron x-ray emission from electron oscillations in laser wakefield acceleration (LWFA) has been widely investigated as a promising source. Betatron x-rays are usually produced via self-injected electron beams, which are not controllable and are not optimized for x-ray yields. Here, we present a new method for bright hard x-ray emission via ionization injection from the K-shell electrons of nitrogen into the accelerating bucket. A total photon yield of 8 × 108/shot and 108 photons with energy greater than 110 keV is obtained. The yield is 10 times higher than that achieved with self-injection mode in helium under similar laser parameters. The simulation suggests that ionization-injected electrons are quickly accelerated to the driving laser region and are subsequently driven into betatron resonance. The present scheme enables the single-stage betatron radiation from LWFA to be extended to bright γ-ray radiation, which is beyond the capability of 3rd generation synchrotrons. PMID:27273170

  20. Calibration of the hard x-ray detectors for the FOXSI solar sounding rocket

    Science.gov (United States)

    Athiray, P. S.; Buitrago-Casas, Juan Camilo; Bergstedt, Kendra; Vievering, Juliana; Musset, Sophie; Ishikawa, Shin-nosuke; Glesener, Lindsay; Takahashi, Tadayuki; Watanabe, Shin; Courtade, Sasha; Christe, Steven; Krucker, Säm.; Goetz, Keith; Monson, Steven

    2017-08-01

    The Focusing Optics X-ray Solar Imager (FOXSI) sounding rocket experiment conducts direct imaging and spectral observation of the Sun in hard X-rays, in the energy range 4 to 20 keV. These high-sensitivity observations are used to study particle acceleration and coronal heating. FOXSI is designed with seven grazing incidence optics modules that focus X-rays onto seven focal plane detectors kept at a 2m distance. FOXSI-1 was flown with seven Double-sided Si Strip Detectors (DSSD), and two of them were replaced with CdTe detectors for FOXSI-2. The upcoming FOXSI-3 flight will carry DSSD and CdTe detectors with upgraded optics for enhanced sensitivity. The detectors are calibrated using various radioactive sources. The detector's spectral response matrix was constructed with diagonal elements using a Gaussian approximation with a spread (sigma) that accounts for the energy resolution of the detector. Spectroscopic studies of past FOXSI flight data suggest that the inclusion of lower energy X-rays could better constrain the spectral modeling to yield a more precise temperature estimation of the hot plasma. This motivates us to carry out an improved calibration to better understand the finer-order effects on the spectral response, especially at lower energies. Here we report our improved calibration of FOXSI detectors using experiments and Monte-Carlo simulations.

  1. Small hard X-ray source using X-band linac

    CERN Document Server

    Uesaka, M; Iijima, H; Tsuchihashi, K; Urakawa, J; Higo, T; Akemoto, M; Hayano, H

    2002-01-01

    For application to dynamic angiographies and life science, small hard X-ray source by laser electron beam collision using X-band linac has been developed. The outline of X-band linac system and the X-ray intensity are discussed. The X-ray intensity of some combinations of laser and electron sources was evaluated by numerical calculations. Four kinds of combinations such as photo-cathode RF-gun + short pulse laser, thermionic-cathode RF-gun + Q-switch Nd:YAG laser, multi-bunch photo-cathode RF-gun + laser accumulator and 200 MeV electron storage ring + laser accumulator were investigated. X-band RF-gun is being used and S-band Mg photo-cathode RF-gun is studied. The X-ray intensity of the thermionic-cathode RF-gun + Q-switch Nd:YAG laser is 10 sup 7 phons/s(total) at 50 keV. This value can be used for structure analysis of protein. (S.Y.)

  2. The hard X-ray response of the XIS-CCD for Astro-E: qualification of the X-ray CCD detector

    CERN Document Server

    Nishiuchi, M; Awaki, H; Tsuru, T; Sakano, M; Hamaguchi, K; Murakami, H; Tsunemi, H; Hayashida, K; Kitamoto, S; Miyata, E; Dotani, T; Ozaki, M; Bautz, M; Doty, J; Kissel, S; Foster, R; Ricker, G

    1999-01-01

    We report on the hard X-ray response of the CCD detector for the X-ray imaging spectrometer (XIS), to be launched on the next Japanese X-ray Astronomical Satellite, ASTRO-E, in February 2000. XIS is prepared by an international team, comprised of MIT (USA), ISAS, Osaka University and Kyoto University (JAPAN). We have evaluated the X-ray response of the XIS in its high-energy band (1.5-10 keV). Data from the fluorescent line emission of Al, Cl, Ti, Ni, Fe, Zn, Se were used to construct the response function of the CCD detectors. Details of the response function - including the energy-scale, linearity, energy resolution, quantum efficiency -, are given as a function of incident X-ray energy. We find that the tail component of high-energy photopeaks are produced by events with incomplete charge collection. We also conclude that the size of the charge clouds can be estimated using the shapes of the tail components.

  3. Optical constants in the hard X-ray/Soft gamma ray range of selected materials for multilayer reflectors

    DEFF Research Database (Denmark)

    Cooper-Jensen, Carsten P.; Romaine, S.; Bruni, R.

    2007-01-01

    Future Astrophysics missions operating in the hard X-ray/Soft Gamma ray range is slated to carry novel focusing telescopes based on the use of depth graded multilayer reflectors. Current design studies show that, at the foreseen focal lengths, it should be feasible to focus X-rays at energies...

  4. THE NuSTAR Hard X-Ray Survey of the Norma Arm Region

    Science.gov (United States)

    Fornasini, Francesca M.; Tomsick, John A.; Hong, Jaesub; Gotthelf, Eric V.; Bauer, Franz; Rahoui, Farid; Stern, Daniel K.; Bodaghee, Arash; Chiu, Jeng-Lun; Clavel, Maïca; hide

    2017-01-01

    We present a catalog of hard X-ray sources in a square-degree region surveyed by the Nuclear Spectroscopic Telescope Array (NuSTAR) in the direction of the Norma spiral arm. This survey has a total exposure time of 1.7 Ms, and the typical and maximum exposure depths are 50 ks and 1 Ms, respectively. In the area of deepest coverage, sensitivity limits of 5 x 10(exp -14) and 4 x 10(exp -14) ergs/s/sq cm in the 3-10 and 10-20 keV bands, respectively, are reached. Twenty-eight sources are firmly detected, and 10 are detected with low significance; 8 of the 38 sources are expected to be active galactic nuclei. The three brightest sources were previously identified as a low-mass X-ray binary, high-mass X-ray binary, and pulsar wind nebula. Based on their X-ray properties and multiwavelength counterparts, we identify the likely nature of the other sources as two colliding wind binaries, three pulsar wind nebulae, a black hole binary, and a plurality of cataclysmic variables (CVs). The CV candidates in the Norma region have plasma temperatures of approx. 10-20 keV, consistent with the Galactic ridge X-ray emission spectrum but lower than the temperatures of CVs near the Galactic center. This temperature difference may indicate that the Norma region has a lower fraction of intermediate polars relative to other types of CVs compared to the Galactic center. The NuSTAR logN-logS distribution in the 10-20keV band is consistent with the distribution measured by Chandra at 2-10 keV if the average source spectrum is assumed to be a thermal model with kT approx. =15 keV, as observed for the CV candidates.

  5. Very hard states in neutron star low-mass X-ray binaries

    Science.gov (United States)

    Parikh, A. S.; Wijnands, R.; Degenaar, N.; Altamirano, D.; Patruno, A.; Gusinskaia, N. V.; Hessels, J. W. T.

    2017-07-01

    We report on unusually very hard spectral states in three confirmed neutron-star low-mass X-ray binaries (1RXS J180408.9-342058, EXO 1745-248 and IGR J18245-2452) at a luminosity between ˜1036 and 1037 erg s-1. When fitting the Swift X-ray spectra (0.5-10 keV) in those states with an absorbed power-law model, we found photon indices of Γ ˜ 1, significantly lower than the Γ = 1.5-2.0 typically seen when such systems are in their so called hard state. For individual sources, very hard spectra were already previously identified, but here we show for the first time that likely our sources were in a distinct spectral state (i.e. different from the hard state) when they exhibited such very hard spectra. It is unclear how such very hard spectra can be formed; if the emission mechanism is similar to that operating in their hard states (i.e. up-scattering of soft photons due to hot electrons), then the electrons should have higher temperatures or a higher optical depth in the very hard state compared to those observed in the hard state. By using our obtained Γ as a tracer for the spectral evolution with luminosity, we have compared our results with those obtained by Wijnands et al. Our sample of sources follows the same track as the other neutron star systems in Wijnands et al., confirming their general results. However, we do not find that the accreting millisecond pulsars are systematically harder than the non-pulsating systems.

  6. INTEGRAL detection of a hard X-ray transient in NGC 6440

    DEFF Research Database (Denmark)

    Kuulkers, E.; Bozzo, E.; Bazzano, A.

    2015-01-01

    position is: RA, Dec (J2000) = 267.208, -20.314 degrees, with an error radius of 2.4 arcmin (90% c.l.). Formally, there is no known X-ray source within the error circle, so we label the source as IGR J17488-2018. The hard X-ray transient is detected at a significance of 11 (6.5) sigma on the IBIS......Referred to by ATel #: 7106, 7136, 7183 Tweet During INTEGRAL Galactic bulge monitoring (e.g., ATel #438) observations performed on UT 2015 February 17 at 12.53-16:45, IBIS/ISGRI detected renewed activity at hard X-rays from a transient within the Globular Cluster NGC 6440. The best determined....../ISGRI mosaic in the 20-40 keV (40-80 keV) energy band. The IBIS/ISGRI spectrum (total exposure time of 12 ks) provides a photon index of 2.4 +/- 0.5 and a 20-100 keV flux of 4.8E-10 ergs/cm^2/s. NGC 6440 was outside the JEM-X field-of-view for the entire observation. The Globular Cluster NGC 6440 is known...

  7. SuperHERO: The Next Generation Hard X-Ray HEROES Telescope

    Science.gov (United States)

    Wilson-Hodge, Colleen A.; Gaskin, Jessica A.; Christe, Steven D.; Elsner, Ronald F.; Ramsey, Brian D.; Seller, Paul; Shih, Albert Y.; Stuchlik, David W.; Swartz, Douglas A.; Tenant, Allyn F.; hide

    2014-01-01

    SuperHERO is a new high-sensitivity Long Duration Balloon (LDB)-capable, hard-x-ray (20-75 keV) telescope for making novel astrophysics and heliophysics observations. The proposed SuperHERO payload will be developed jointly by the Astrophysics Office at NASA Marshall Space Flight Center, the Solar Physics Laboratory and Wallops Flight Facility at NASA Goddard Space Flight Center. SuperHERO is a follow-on payload to the High Energy Replicated Optics to Explore the Sun (HEROES) balloon-borne telescope that recently launched from Fort Sumner, NM in September of 2013. The HEROES core instrument is a hard x-ray telescope consisting of x-ray 109 optics configured into 8 modules. Each module is aligned to a matching gas-filled detector at a focal length of 6 m. SuperHERO will make significant improvements to the HEROES payload, including: new solid-state multi-pixel CdTe detectors, additional optics, the Wallops Arc-Second Pointer, alignment monitoring systems and lighter gondola.

  8. Measured reflectance of graded multilayer mirrors designed for astronomical hard X-ray telescopes

    DEFF Research Database (Denmark)

    Christensen, Finn Erland; Craig, W.W.; Windt, D.L.

    2000-01-01

    Future astronomical X-ray telescopes, including the balloon-borne High-Energy Focusing Telescope (HEFT) and the Constellation-X Hard X-ray Telescope (Con-X HXT) plan to incorporate depth-graded multilayer coatings in order to extend sensitivity into the hard X-ray (10 less than or similar to E less......-graded W/Si multilayers optimized for broadband performance up to 69.5 keV (WK-edge). These designs are ideal for both the HEFT and Con-X HXT applications. We compare the measurements to model calculations to demonstrate that the reflectivity can be well described by the intended power law distribution...... than or similar to 80 keV) band. In this paper, we present measurements of the reflectance in the 18-170 keV energy range of a cylindrical prototype nested optic taken at the European Synchrotron Radiation Facility (ESRF). The mirror segments, mounted in a single bounce stack, are coated with depth...

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

    Science.gov (United States)

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

    1985-01-01

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

  10. Unveiling the Structure of Active Galactic Nuclei with Hard X-ray Spectroscopy

    Science.gov (United States)

    Balokovic, Mislav

    Despite the long history of studies of active galactic nuclei (AGN), details of the structure of the accretion flow onto supermassive black holes are far from clear. Work presented in this thesis is directed at unveiling properties of AGN structure through broadband X-ray spectroscopy, with particular emphasis on the hard X-ray band (photon energies above 10 keV). With its unprecedented sensitivity in this energy band, the NuSTAR telescope provides the key observational diagnostics of the properties of the AGN X-ray source, the corona, and the surrounding gas in the accretion disk, the broad-line region, and the torus. The first study presented in this thesis focuses on measurements of the optical depth and the temperature of the plasma in the corona of an obscured AGN. Fitting theoretical spectral models for coronal emission to the NuSTAR data constrained these two basic physical parameters under the assumption of either spherical or disk-like geometry for the corona. The remainder of the thesis is dedicated to studies of the anisotropic obscuring structure broadly referred to as the torus. One of them is a case study of three heavily obscured AGN with spectra dominated by the X-ray light scattered and reprocessed in the torus, where it is possible to constrain one of the basic torus properties - its globally averaged column density. The following study presents the calculation of a new spectral model for reprocessing of the intrinsic X-ray continuum within the torus. Its added flexibility compared to previously available models allows for both the average column density of the torus and its covering factor to be constrained from broadband X-ray spectra of a wide variety of AGN. The final part of the thesis in based on a large survey of the local obscured AGN population performed with NuSTAR. Spectral modeling of more than a hundred individual AGN, including both old and new spectral models, is presented. From analyses of the X-ray data for a large and

  11. SuperAGILE: The hard X-ray imager for the AGILE space mission

    Science.gov (United States)

    Feroci, M.; Costa, E.; Soffitta, P.; Del Monte, E.; di Persio, G.; Donnarumma, I.; Evangelista, Y.; Frutti, M.; Lapshov, I.; Lazzarotto, F.; Mastropietro, M.; Morelli, E.; Pacciani, L.; Porrovecchio, G.; Rapisarda, M.; Rubini, A.; Tavani, M.; Argan, A.

    2007-11-01

    SuperAGILE is a coded mask experiment based on silicon microstrip detectors. It operates in the 15 45 keV nominal energy range, providing crossed one-dimensional images of the X-ray sky with an on-axis angular resolution of 6 arcmin, over a field of view in excess of 1 sr. It was designed as the hard X-ray monitor of the AGILE space mission, a small satellite of the Italian Space Agency devoted to image the gamma-ray sky in the 30 MeV 50 GeV energy band. The AGILE mission was launched in a low-earth orbit on 23rd April 2007. In this paper we describe the SuperAGILE experiment, its construction and test processes, and its performance before flight, based on the on-ground test and calibrations.

  12. In situ/Operando studies of electrocatalysts using hard X-ray spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Lassalle-Kaiser, Benedikt [Synchrotron SOLEIL, Gif-sur-Yvette (France); Gul, Sheraz [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Molecular Biophysics and Integrated Bioimaging Div.; Kern, Jan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Molecular Biophysics and Integrated Bioimaging Div.; SLAC National Accelerator Lab., Menlo Park, CA (United States). Linac Coherent Light Source (LCLS); Yachandra, Vittal K. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Molecular Biophysics and Integrated Bioimaging Div.; Yano, Junko [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Molecular Biophysics and Integrated Bioimaging Div.

    2017-05-02

    This review focuses on the use of X-ray absorption and emission spectroscopy techniques using hard X-rays to study electrocatalysts under in situ/operando conditions. The importance and the versatility of methods in the study of electrodes in contact with the electrolytes are described, when they are being cycled through the catalytic potentials during the progress of the oxygen-evolution, oxygen reduction and hydrogen evolution reactions. The catalytic oxygen evolution reaction is illustrated with examples using three oxides, Co, Ni and Mn, and two sulfides, Mo and Co. These are used as examples for the hydrogen evolution reaction. A bimetallic, bifunctional oxygen evolving and oxygen reducing Ni/Mn oxide is also presented. The various advantages and constraints in the use of these techniques and the future outlook are discussed.

  13. In Situ Ptychography of Heterogeneous Catalysts using Hard X-Rays

    DEFF Research Database (Denmark)

    Baier, Sina; Damsgaard, Christian Danvad; Scholz, Maria

    2016-01-01

    A new closed cell is presented for in situ X-ray ptychography which allows studies under gas flow and at elevated temperature. In order to gain complementary information by transmission and scanning electron microscopy, the cell makes use of a Protochips E-chipTM which contains a small, thin...... electron transparent window and allows heating. Two gold-based systems, 50 nm gold particles and nanoporous gold as a relevant catalyst sample, were used for studying the feasibility of the cell. Measurements showing a resolution around 40 nm have been achieved under a flow of synthetic air and during...... heating up to temperatures of 933 K. An elevated temperature exhibited little influence on image quality and resolution. With this study, the potential of in situ hard X-ray ptychography for investigating annealing processes of real catalyst samples is demonstrated. Furthermore, the possibility to use...

  14. Evidence for Intermediate Polars as the Origin of the Galactic Center Hard X-ray Emission

    DEFF Research Database (Denmark)

    Hailey, Charles J.; Mori, Kaya; Perez, Kerstin

    2016-01-01

    Recently, unresolved hard (20-40 keV) X-ray emission has been discovered within the central 10 pc of the Galaxy, possibly indicating a large population of intermediate polars (IPs). Chandra and XMM-Newton measurements in the surrounding ∼50 pc imply a much lighter population of IPs with 〈MWD〉≈0.5H...... estimated white dwarf mass. Observations of the inner 10 pc can be accounted for by IPs with 〈MWD〉≈0.9M⊙, consistent with that of the CV population in general and the X-ray observed field IPs in particular. The lower mass derived by Chandra and XMM-Newton appears to be an artifact of narrow energy...

  15. Weak Hard X-Ray Emission from Broad Absorption Line Quasars: Evidence for Intrinsic X-Ray Weakness

    DEFF Research Database (Denmark)

    Luo, B.; Brandt, W. N.; Alexander, D. M.

    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 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...

  16. ID16B: a hard X-ray nanoprobe beamline at the ESRF for nano-analysis.

    Science.gov (United States)

    Martínez-Criado, Gema; Villanova, Julie; Tucoulou, Rémi; Salomon, Damien; Suuronen, Jussi-Petteri; Labouré, Sylvain; Guilloud, Cyril; Valls, Valentin; Barrett, Raymond; Gagliardini, Eric; Dabin, Yves; Baker, Robert; Bohic, Sylvain; Cohen, Cédric; Morse, John

    2016-01-01

    Within the framework of the ESRF Phase I Upgrade Programme, a new state-of-the-art synchrotron beamline ID16B has been recently developed for hard X-ray nano-analysis. The construction of ID16B was driven by research areas with major scientific and societal impact such as nanotechnology, earth and environmental sciences, and bio-medical research. Based on a canted undulator source, this long beamline provides hard X-ray nanobeams optimized mainly for spectroscopic applications, including the combination of X-ray fluorescence, X-ray diffraction, X-ray excited optical luminescence, X-ray absorption spectroscopy and 2D/3D X-ray imaging techniques. Its end-station re-uses part of the apparatus of the earlier ID22 beamline, while improving and enlarging the spectroscopic capabilities: for example, the experimental arrangement offers improved lateral spatial resolution (∼50 nm), a larger and more flexible capability for in situ experiments, and monochromatic nanobeams tunable over a wider energy range which now includes the hard X-ray regime (5-70 keV). This paper describes the characteristics of this new facility, short-term technical developments and the first scientific results.

  17. Uncooled Radiation Hard Large Area SiC X-ray and EUV Detectors and 2D Arrays Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This project seeks to design, fabricate, characterize and commercialize large area, uncooled and radiative hard 4H-SiC EUV ? soft X-ray detectors capable of ultra...

  18. Energetic electrons, hard x-ray emission and MHD activity studies in the IR-T1 tokamak.

    Science.gov (United States)

    Agah, K Mikaili; Ghoranneviss, M; Elahi, A Salar

    2015-01-01

    Determinations of plasma parameters as well as the Magnetohydrodynamics (MHD) activity, energetic electrons energy and energy confinement time are essential for future fusion reactors experiments and optimized operation. Also some of the plasma information can be deduced from these parameters, such as plasma equilibrium, stability, and MHD instabilities. In this contribution we investigated the relation between energetic electrons, hard x-ray emission and MHD activity in the IR-T1 Tokamak. For this purpose we used the magnetic diagnostics and a hard x-ray spectroscopy in IR-T1 tokamak. A hard x-ray emission is produced by collision of the runaway electrons with the plasma particles or limiters. The mean energy was calculated from the slope of the energy spectrum of hard x-ray photons.

  19. Design and performance of an X-ray scanning microscope at the Hard X-ray Nanoprobe beamline of NSLS-II.

    Science.gov (United States)

    Nazaretski, E; Yan, H; Lauer, K; Bouet, N; Huang, X; Xu, W; Zhou, J; Shu, D; Hwu, Y; Chu, Y S

    2017-11-01

    A hard X-ray scanning microscope installed at the Hard X-ray Nanoprobe beamline of the National Synchrotron Light Source II has been designed, constructed and commissioned. The microscope relies on a compact, high stiffness, low heat dissipation approach and utilizes two types of nanofocusing optics. It is capable of imaging with ∼15 nm × 15 nm spatial resolution using multilayer Laue lenses and 25 nm × 26 nm resolution using zone plates. Fluorescence, diffraction, absorption, differential phase contrast, ptychography and tomography are available as experimental techniques. The microscope is also equipped with a temperature regulation system which allows the temperature of a sample to be varied in the range between 90 K and 1000 K. The constructed instrument is open for general users and offers its capabilities to the material science, battery research and bioscience communities.

  20. Generation of hard X-ray from solid target irradiated by UV high intensity ultrashort pulse laser

    CERN Document Server

    Tao Ye; Tang Xiu Zhang; Shan Yu Sheng; Wang Nai Yan

    2002-01-01

    Hard X-ray continuum generated from interaction of UV high intensity ultrashort pulse laser with solid target has been investigated by experiment. P-polarized light irradiating 5 mm Cu slab with 45 degree, the hard X-ray with energy of 200 keV has been detected. Fitting the experiment data by Maxwellian distribution, the temperature of hot electron is 67 keV. The experiment data are the results of combination of several absorption mechanisms

  1. The Cosmic Evolution of Hard X-Ray-selected Active Galactic Nuclei

    Science.gov (United States)

    Barger, A. J.; Cowie, L. L.; Mushotzky, R. F.; Yang, Y.; Wang, W.-H.; Steffen, A. T.; Capak, P.

    2005-02-01

    We use highly spectroscopically complete deep and wide-area Chandra surveys to determine the cosmic evolution of hard X-ray-selected active galactic nuclei (AGNs). For the deep fields, we supplement the spectroscopic redshifts with photometric redshifts to assess where the unidentified sources are likely to lie. We find that the median redshifts are fairly constant with X-ray flux at z~1. We classify the optical spectra and measure the FWHM line widths. Most of the broad-line AGNs show essentially no visible absorption in X-rays, whereas the sources without broad lines (FWHM=1042 ergs s-1 and for broad-line AGNs alone. At zevolution, with L* evolving as (1+z)3.2+/-0.8 for all spectral types and as (1+z)3.0+/-1.0 for broad-line AGNs alone. Thus, all AGNs drop in luminosity by almost an order of magnitude over this redshift range. We show that this observed drop is due to AGN downsizing rather than to an evolution in the accretion rates onto the supermassive black holes. We directly compare our broad-line AGN hard X-ray luminosity functions with the optical QSO luminosity functions and find that at the bright end they agree extremely well at all redshifts. However, the optical QSO luminosity functions do not probe faint enough to see the downturn in the broad-line AGN hard X-ray luminosity functions and even appear to be missing some sources at the lowest luminosities they probe. We find that broad-line AGNs dominate the number densities at the higher X-ray luminosities, while optically narrow AGNs dominate at the lower X-ray luminosities. We rule out galaxy dilution as a partial explanation for this effect by measuring the nuclear UV/optical properties of the Chandra sources using the Hubble Space Telescope Advanced Camera for Surveys GOODS-North data. The UV/optical nuclei of the optically narrow AGNs are much weaker than expected if the optically narrow AGNs were similar to the broad-line AGNs. We therefore postulate the need for a luminosity-dependent unified

  2. Mosaic GaAs crystals for hard x-ray astronomy

    Science.gov (United States)

    Ferrari, C.; Zanotti, L.; Zappettini, A.; Arumainathan, S.

    2008-08-01

    Recently the design of a Laue lens with field of view of 30 arcseconds and for x-rays in the energy range from 100 keV to 1 MeV has been proposed in which mosaic crystals are used as focussing elements. The proper mosaic angular spread is chosen as a compromise between intensity and energy resolution of the Laue lens. In the present work we consider the use of GaAs crystals as optical elements for hard x-ray astronomy. GaAs crystals have essentially the same electron density and lattice spacing as germanium, and are characterized by spontaneous formation of "cellular structures" with dislocations distribution at the boundaries between perfect zones of the crystal. Because of the presence of cellular structures Czochralsky grown GaAs show a natural degree of mosaicity. Several GaAs ingots grown by liquid encapsulating Czochralsky technique have been characterized by high resolution x-ray diffraction. Bragg diffraction profiles have been measured along ingot axes and diameters of doped, undoped or stoichiometry deviated GaAs crystals. Full width at half maximum values ranging from 15 to 40 arcseconds depending on the position were measured close to the proposed 30 arcsecond mosaicity required for the Laue lens. Appropriate growth conditions allow the control of the dislocation density and the modification of cellular structure responsible of the crystal mosaicity so that the possibility of obtaining crystals with a given degree of mosaicity by tuning the LEC growth conditions is proposed.

  3. First NuSTAR Limits on Quiet Sun Hard X-Ray Transient Events

    DEFF Research Database (Denmark)

    Marsh, Andrew J.; Smith, David M.; Glesener, Lindsay

    2017-01-01

    We present the first results of a search for transient hard X-ray (HXR) emission in the quiet solar corona with the Nuclear Spectroscopic Telescope Array (NuSTAR) satellite. While NuSTAR was designed as an astrophysics mission, it can observe the Sun above 2 keV with unprecedented sensitivity due...... to its pioneering use of focusing optics. NuSTAR first observed quiet-Sun regions on 2014 November 1, although out-of-view active regions contributed a notable amount of background in the form of single-bounce (unfocused) X-rays. We conducted a search for quiet-Sun transient brightenings on timescales...... as model-independent photon fluxes. The limits in both bands are well below previous HXR microflare detections, though not low enough to detect events of equivalent T and EM as quiet-Sun brightenings seen in soft X-ray observations. We expect future observations during solar minimum to increase the Nu...

  4. First NuSTAR Limits on Quiet Sun Hard X-Ray Transient Events

    Science.gov (United States)

    Marsh, Andrew J.; Smith, David M.; Glesener, Lindsay; Hannah, Iain G.; Grefenstette, Brian W.; Caspi, Amir; Krucker, Säm; Hudson, Hugh S.; Madsen, Kristin K.; White, Stephen M.; Kuhar, Matej; Wright, Paul J.; Boggs, Steven E.; Christensen, Finn E.; Craig, William W.; Hailey, Charles J.; Harrison, Fiona A.; Stern, Daniel; Zhang, William W.

    2017-11-01

    We present the first results of a search for transient hard X-ray (HXR) emission in the quiet solar corona with the Nuclear Spectroscopic Telescope Array (NuSTAR) satellite. While NuSTAR was designed as an astrophysics mission, it can observe the Sun above 2 keV with unprecedented sensitivity due to its pioneering use of focusing optics. NuSTAR first observed quiet-Sun regions on 2014 November 1, although out-of-view active regions contributed a notable amount of background in the form of single-bounce (unfocused) X-rays. We conducted a search for quiet-Sun transient brightenings on timescales of 100 s and set upper limits on emission in two energy bands. We set 2.5-4 keV limits on brightenings with timescales of 100 s, expressed as the temperature T and emission measure EM of a thermal plasma. We also set 10-20 keV limits on brightenings with timescales of 30, 60, and 100 s, expressed as model-independent photon fluxes. The limits in both bands are well below previous HXR microflare detections, though not low enough to detect events of equivalent T and EM as quiet-Sun brightenings seen in soft X-ray observations. We expect future observations during solar minimum to increase the NuSTAR sensitivity by over two orders of magnitude due to higher instrument livetime and reduced solar background.

  5. Evaluating scintillator performance in time-resolved hard X-ray studies at synchrotron light sources

    Energy Technology Data Exchange (ETDEWEB)

    Rutherford, Michael E.; Chapman, David J.; White, Thomas G. [Imperial College London, London (United Kingdom); Drakopoulos, Michael [Diamond Light Source, I12 Joint Engineering, Environmental, Processing (JEEP) Beamline, Didcot, Oxfordshire (United Kingdom); Rack, Alexander [European Synchrotron Radiation Facility, Grenoble (France); Eakins, Daniel E., E-mail: d.eakins@imperial.ac.uk [Imperial College London, London (United Kingdom)

    2016-03-24

    Scintillator performance in time-resolved, hard, indirect detection X-ray studies on the sub-microsecond timescale at synchrotron light sources is reviewed, modelled and examined experimentally. LYSO:Ce is found to be the only commercially available crystal suitable for these experiments. The short pulse duration, small effective source size and high flux of synchrotron radiation is ideally suited for probing a wide range of transient deformation processes in materials under extreme conditions. In this paper, the challenges of high-resolution time-resolved indirect X-ray detection are reviewed in the context of dynamic synchrotron experiments. In particular, the discussion is targeted at two-dimensional integrating detector methods, such as those focused on dynamic radiography and diffraction experiments. The response of a scintillator to periodic synchrotron X-ray excitation is modelled and validated against experimental data collected at the Diamond Light Source (DLS) and European Synchrotron Radiation Facility (ESRF). An upper bound on the dynamic range accessible in a time-resolved experiment for a given bunch separation is calculated for a range of scintillators. New bunch structures are suggested for DLS and ESRF using the highest-performing commercially available crystal LYSO:Ce, allowing time-resolved experiments with an interframe time of 189 ns and a maximum dynamic range of 98 (6.6 bits)

  6. Phase-matched generation of coherent soft and hard X-rays using IR lasers

    Science.gov (United States)

    Popmintchev, Tenio V.; Chen, Ming-Chang; Bahabad, Alon; Murnane, Margaret M.; Kapteyn, Henry C.

    2013-06-11

    Phase-matched high-order harmonic generation of soft and hard X-rays is accomplished using infrared driving lasers in a high-pressure non-linear medium. The pressure of the non-linear medium is increased to multi-atmospheres and a mid-IR (or higher) laser device provides the driving pulse. Based on this scaling, also a general method for global optimization of the flux of phase-matched high-order harmonic generation at a desired wavelength is designed.

  7. A Hard X-Ray Power-Law Spectral Cutoff in Centaurus X-4

    DEFF Research Database (Denmark)

    Chakrabarty, Deepto; Tomsick, John A.; Grefenstette, Brian W.

    2015-01-01

    The low-mass X-ray binary Cen X-4 is the brightest and closest (soft thermal emission from the neutron star atmosphere and a hard power-law tail of unknown...... inhibited by the magnetic propeller effect. The power-law cutoff energy is set by the degree of Compton cooling of the RIAF electrons by thermal seed photons from the neutron star atmosphere. Lower thermal luminosities should lead to higher (possibly undetectable) cutoff energies. We compare Cen~X-4's...

  8. NuSTAR hard x-ray optics design and performance

    DEFF Research Database (Denmark)

    Koglin, J. E.; An, H.; Blaedel, K. L.

    2009-01-01

    The Nuclear Spectroscopic Telescope Array (NuSTAR) is a NASA satellite mission scheduled for launch in 2011. Using focusing optics with multilayer coating for enhanced reflectivity of hard X-rays (6-79 keV), NuSTAR will provide a combination of clarity, sensitivity and spectral resolution...... surpassing the largest observatories in this band by orders of magnitude. This advance will allow NuSTAR to test theories of how heavy elements are born, discover collapsed stars and black holes on all scales and explore the most extreme physical environments. We will present an overview of the NuSTAR optics...

  9. Hard X-ray nanoimaging method using local diffraction from metal wire

    Energy Technology Data Exchange (ETDEWEB)

    Takano, Hidekazu, E-mail: htakano@sci.u-hyogo.ac.jp; Konishi, Shigeki; Shimomura, Sho; Azuma, Hiroaki; Tsusaka, Yoshiyuki; Kagoshima, Yasushi [Center for Novel Material Science under Multi-Extreme Conditions, Graduate School of Material Science, University of Hyogo, Kamigori, Hyogo 678-1297 (Japan)

    2014-01-13

    A simple hard X-ray imaging method achieving a high spatial resolution is proposed. Images are obtained by scanning a metal wire through the wave field to be measured and rotating the sample to collect data for back projection calculations; the local diffraction occurring at the edges of the metal wire operates as a narrow line probe. In-line holograms of a test sample were obtained with a spatial resolution of better than 100 nm. The potential high spatial resolution of this method is shown by calculations using diffraction theory.

  10. Hard x-ray spectrum emitted by a plasma focus optimized for flash radiography

    Science.gov (United States)

    Raspa, V.; Moreno, C.; Sigaut, L.; Clausse, A.

    2008-10-01

    The effective spectrum of the hard x-ray output of a Mather-type tabletop plasma focus device was determined from attenuation data on metallic samples using commercial radiographic film coupled to a Gd2O2S: Tb phosphor intensifier screen. It was found that the radiation has relevant spectral components in the 40-150 keV range, with a single maximum around 60-80 keV. The radiation output allows for 50 ns resolution, good contrast, introspective imaging of metallic objects even through metallic walls. A numerical estimation of the induced voltage on the focus during the compressional stage is briefly discussed.

  11. Application of an EMCCD Camera for Calibration of Hard X-Ray Telescopes

    Energy Technology Data Exchange (ETDEWEB)

    Vogel, J K; Pivovaroff, M J; Nagarkar, V V; Kudrolli, H; Madsen, K K; Koglin, J E; Christensen, F E; Brejnholt, N F

    2011-11-08

    Recent technological innovations now make it feasible to construct hard x-ray telescopes for space-based astronomical missions. Focusing optics are capable of improving the sensitivity in the energy range above 10 keV by orders of magnitude compared to previously used instruments. The last decade has seen focusing optics developed for balloon experiments and they will soon be implemented in approved space missions such as the Nuclear Spectroscopic Telescope Array (NuSTAR) and ASTRO-H. The full characterization of x-ray optics for astrophysical and solar imaging missions, including measurement of the point spread function (PSF) as well as scattering and reflectivity properties of substrate coatings, requires a very high spatial resolution, high sensitivity, photon counting and energy discriminating, large area detector. Novel back-thinned Electron Multiplying Charge-Coupled Devices (EMCCDs) are highly suitable detectors for ground-based calibrations. Their chip can be optically coupled to a microcolumnar CsI(Tl) scintillator via a fiberoptic taper. Not only does this device exhibit low noise and high spatial resolution inherent to CCDs, but the EMCCD is also able to handle high frame rates due to its controllable internal gain. Additionally, thick CsI(Tl) yields high detection efficiency for x-rays. This type of detector has already proven to be a unique device very suitable for calibrations in astrophysics: such a camera was used to support the characterization of the performance for all NuSTAR optics. Further optimization will enable similar cameras to be improved and used to calibrate x-ray telescopes for future space missions. In this paper, we discuss the advantages of using an EMCCD to calibrate hard x-ray optics. We will illustrate the promising features of this detector solution using examples of data obtained during the ground calibration of the NuSTAR telescopes performed at Columbia University during 2010/2011. Finally, we give an outlook on ongoing

  12. Nuclear absorption and emission in the AGN merger NGC 6240 : the hard X-ray view

    Science.gov (United States)

    Nardini, Emanuele

    2017-11-01

    We present the analysis of four NuSTAR observations of the luminous infrared galaxy merger NGC 6240 , hosting a close pair of highly obscured active galactic nuclei (AGNs). Over a period of about 2 yr, the source exhibits hard X-ray variability of the order of 20 per cent, peaking around 20 keV. When the two AGNs are resolved with Chandra , column densities in the range of NH ˜ 1-2 × 1024 cm-2 are estimated for both of them. The exact values are hard to determine, as they appear to depend on aspects that are sometimes overlooked in Compton-thick objects, such as the covering factor of the absorber, iron abundance and the contamination in the Fe K band from foreground hot-gas emission. Nearly spherical covering and slightly subsolar iron abundance are preferred in this case. While the southern nucleus is suggested to be intrinsically more powerful, as also implied by the mid-IR and 2-10 keV brightness ratios, solutions involving a similar X-ray luminosity of the two AGNs cannot be ruled out. The observed variability is rather limited compared to the one revealed by the Swift /BAT light curve, and it can be fully explained by changes in the continuum flux from the two AGNs, without requiring significant column density variations. NGC 6240 is hereby confirmed to represent a unique opportunity to investigate the X-ray (and broad-band) properties of massive galaxy mergers, which were much more frequent in the early Universe.

  13. HERO: A Hard-X-Ray Balloon-Borne Focusing Telescope

    Science.gov (United States)

    Ramsey, Brian; Stahl, H. Philip

    2008-01-01

    HERO, for High Energy Replicated Optics, is an evolutionary balloon payload featuring hard-X-ray grazing-incidence nickel optics. The payload provides a scientific instrument capable of high-sensitivity observations in an energy regime that is relatively unexplored at fine spatial scales, and also serves as a demonstration vehicle for in-house fabricated optics and focal plane detectors. After a proof-of-concept flight in 2001, which captured the first focused hard-X-ray images galactic sources, HERO has been significantly expanded from just 6, 3-m-focal length mirror shells to its current complement of nearly 100, 6-m-focal length mirrors. HERO was flown in 2007, from Fort Sumner, NM, and is scheduled to fly again in September 2009, from Alice Springs, NT. Full details of the payload will be provided along with preliminary data from the previous flight and science targets for the next flight, where the galactic center region will be imaged.

  14. HERO: High Energy Replicated Optics for a Hard-X-Ray Balloon Payload

    Science.gov (United States)

    Ramsey, B.; Engelhaupt, D.; Speegle, C. O.; ODell, S. L.; Austin, R. A.; Elsner, R. F.; Kolodziejczak, J. J.; Weisskopf, M. C.

    2000-01-01

    We are developing high-energy grazing-incidence replicated optics for a balloon-borne hard-x-ray telescope. When completed, the instrument will have 170 cm2 of effective collecting area at 40 keV and 130 square cm at 60 keV with <= 30 arc seconds half power diameter. This payload will offer unprecedented sensitivity in the hard-x-ray region, with around 250 microCrab sensitivity on long-duration flights and 50-100 microCrab on ultra- long-duration balloon missions The payload consists of 16 mirror modules, each with 14 nested mirrors made from a high-strength nickel alloy, and a corresponding array of 16 focal plane detectors. An engineering demonstration flight is scheduled for the Spring of 2000, using just two mirror modules each with 3 shells, above a pair of gas-scintillation-proportional counters. This flight is intended to test a newly designed gondola pointing and aspect system and the stability of the optical bench design. The first scientific flight of the full payload is scheduled for the Fall of 2002. Full details of the payload and its capabilities will be presented together with data from various mirror-module tests. If available data from the first flight will also be presented.

  15. Hard X-ray submicrometer tomography of human brain tissue at Diamond Light Source

    Science.gov (United States)

    Khimchenko, A.; Bikis, C.; Schulz, G.; Zdora, M.-C.; Zanette, I.; Vila-Comamala, J.; Schweighauser, G.; Hench, J.; Hieber, S. E.; Deyhle, H.; Thalmann, P.; Müller, B.

    2017-06-01

    There is a lack of the necessary methodology for three-dimensional (3D) investigation of soft tissues with cellular resolution without staining or tissue transformation. Synchrotron radiation based hard X-ray in-line phase contrast tomography using single-distance phase reconstruction (SDPR) provides high spatial resolution and density contrast for the visualization of individual cells using a standard specimen preparation and data reconstruction. In this study, we demonstrate the 3D characterization of a formalin-fixed paraffin-embedded (FFPE) human cerebellum specimen by SDPR at the Diamond-Manchester Imaging Branchline I13-2 (Diamond Light Source, UK) at pixel sizes down to 0.45 μm. The approach enables visualization of cerebellar layers (Stratum moleculare and Stratum granulosum), the 3D characterization of individual cells (Purkinje, stellate and granule cells) and can even resolve some subcellular structures (nucleus and nucleolus of Purkinje cells). The tomographic results are qualitatively compared to hematoxylin and eosin (H&E) stained histological sections. We demonstrate the potential benefits of hard X-ray microtomography for the investigations of biological tissues in comparison to conventional histology.

  16. The NuSTAR Hard X-Ray Survey of the Norma Arm Region

    Energy Technology Data Exchange (ETDEWEB)

    Fornasini, Francesca M. [Astronomy Department, University of California, 601 Campbell Hall, Berkeley, CA 94720 (United States); Tomsick, John A.; Chiu, Jeng-Lun; Clavel, Maïca; Krivonos, Roman A.; Boggs, Steven E.; Craig, William W. [Space Sciences Laboratory, 7 Gauss Way, University of California, Berkeley, CA 94720 (United States); Hong, JaeSub [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Gotthelf, Eric V.; Hailey, Charles J.; Mori, Kaya [Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); Bauer, Franz; Corral-Santana, Jesús [Instituto de Astrofísica and Centro de Astroingeniería, Facultad de Física, Pontificia Universidad Católica de Chile, Casilla 306, Santiago 22 (Chile); Rahoui, Farid [European Southern Observatory, K. Schwarzschild-Strasse 2, D-85748 Garching bei München (Germany); Stern, Daniel [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Bodaghee, Arash [Georgia College, 231 W. Hancock Street, Milledgeville, GA 31061 (United States); Alexander, David M. [Centre for Extragalactic Astronomy, Department of Physics, Durham University, Durham, DH1 3LE (United Kingdom); Barret, Didier [Université de Toulouse, UPS-OMP, IRAP, Toulouse (France); CNRS, Institut de Recherche en Astrophysique et Planétologie, 9 Av. colonel Roche, BP 44346, F-31028 Toulouse cedex 4 (France); Christensen, Finn E., E-mail: f.fornasini@berkeley.edu [DTU Space—National Space Institute, Technical University of Denmark, Elektrovej 327, DK-2800 Lyngby (Denmark); and others

    2017-04-01

    We present a catalog of hard X-ray sources in a square-degree region surveyed by the Nuclear Spectroscopic Telescope Array ( NuSTAR ) in the direction of the Norma spiral arm. This survey has a total exposure time of 1.7 Ms, and the typical and maximum exposure depths are 50 ks and 1 Ms, respectively. In the area of deepest coverage, sensitivity limits of 5 × 10{sup −14} and 4 × 10{sup −14} erg s{sup −1} cm{sup −2} in the 3–10 and 10–20 keV bands, respectively, are reached. Twenty-eight sources are firmly detected, and 10 are detected with low significance; 8 of the 38 sources are expected to be active galactic nuclei. The three brightest sources were previously identified as a low-mass X-ray binary, high-mass X-ray binary, and pulsar wind nebula. Based on their X-ray properties and multiwavelength counterparts, we identify the likely nature of the other sources as two colliding wind binaries, three pulsar wind nebulae, a black hole binary, and a plurality of cataclysmic variables (CVs). The CV candidates in the Norma region have plasma temperatures of ≈10–20 keV, consistent with the Galactic ridge X-ray emission spectrum but lower than the temperatures of CVs near the Galactic center. This temperature difference may indicate that the Norma region has a lower fraction of intermediate polars relative to other types of CVs compared to the Galactic center. The NuSTAR log N –log S distribution in the 10–20 keV band is consistent with the distribution measured by Chandra at 2–10 keV if the average source spectrum is assumed to be a thermal model with kT  ≈ 15 keV, as observed for the CV candidates.

  17. A Hard X-Ray Study of the Normal Star-Forming Galaxy M83 with NuSTAR

    DEFF Research Database (Denmark)

    Yukita, M.; Hornschemeier, A. E.; Lehmer, B. D.

    2016-01-01

    We present the results from sensitive, multi-epoch NuSTAR observations of the late-type star-forming galaxy M83 (d = 4.6 Mpc). This is the first investigation to spatially resolve the hard (E > 10 keV) X-ray emission of this galaxy. The nuclear region and similar to 20 off-nuclear point sources......, including a previously discovered ultraluminous X-ray source, are detected in our NuSTAR observations. The X-ray hardnesses and luminosities of the majority of the point sources are consistent with hard X-ray sources resolved in the starburst galaxy NGC 253. We infer that the hard X-ray emission is most...... XLF in NGC 253, which is consistent with previous measurements by Chandra at softer X-ray energies. The NuSTAR integrated galaxy spectrum of M83 drops quickly above 10 keV, which is also seen in the starburst galaxies NGC 253, NGC 3310, and NGC 3256. The NuSTAR observations constrain any active...

  18. Improvement of density resolution in short-pulse hard x-ray radiographic imaging using detector stacks

    Energy Technology Data Exchange (ETDEWEB)

    Borm, B.; Gärtner, F.; Khaghani, D. [GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt (Germany); Johann Wolfgang Goethe-Universität, Frankfurt am Main (Germany); Neumayer, P. [GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt (Germany)

    2016-09-15

    We demonstrate that stacking several imaging plates (IPs) constitutes an easy method to increase hard x-ray detection efficiency. Used to record x-ray radiographic images produced by an intense-laser driven hard x-ray backlighter source, the IP stacks resulted in a significant improvement of the radiograph density resolution. We attribute this to the higher quantum efficiency of the combined detectors, leading to a reduced photon noise. Electron-photon transport simulations of the interaction processes in the detector reproduce the observed contrast improvement. Increasing the detection efficiency to enhance radiographic imaging capabilities is equally effective as increasing the x-ray source yield, e.g., by a larger drive laser energy.

  19. Nonlinear delayed symmetry breaking in a solid excited by hard x-ray free electron laser pulses

    Energy Technology Data Exchange (ETDEWEB)

    Ferrer, A., E-mail: aferrer@phys.ethz.ch [Institute for Quantum Electronics, ETH Zurich, CH-8093 Zurich (Switzerland); Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland); Johnson, J. A., E-mail: jjohnson@chem.byu.edu; Mariager, S. O.; Grübel, S.; Staub, U. [Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland); Huber, T.; Trant, M.; Johnson, S. L., E-mail: johnson@phys.ethz.ch [Institute for Quantum Electronics, ETH Zurich, CH-8093 Zurich (Switzerland); Zhu, D.; Chollet, M.; Robinson, J.; Lemke, H. T. [LCLS, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Ingold, G.; Beaud, P. [Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland); SwissFEL, Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland); Milne, C. [SwissFEL, Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland)

    2015-04-13

    We have studied the ultrafast changes of electronic states in bulk ZnO upon intense hard x-ray excitation from a free electron laser. By monitoring the transient anisotropy induced in an optical probe beam, we observe a delayed breaking of the initial c-plane symmetry of the crystal that lasts for several picoseconds. Interaction with the intense x-ray pulses modifies the electronic state filling in a manner inconsistent with a simple increase in electronic temperature. These results may indicate a way to use intense ultrashort x-ray pulses to investigate high-energy carrier dynamics and to control certain properties of solid-state materials.

  20. CdTe Focal Plane Detector for Hard X-Ray Focusing Optics

    Science.gov (United States)

    Seller, Paul; Wilson, Matthew D.; Veale, Matthew C.; Schneider, Andreas; Gaskin, Jessica; Wilson-Hodge, Colleen; Christe, Steven; Shih, Albert Y.; Inglis, Andrew; Panessa, Marco

    2015-01-01

    The demand for higher resolution x-ray optics (a few arcseconds or better) in the areas of astrophysics and solar science has, in turn, driven the development of complementary detectors. These detectors should have fine pixels, necessary to appropriately oversample the optics at a given focal length, and an energy response also matched to that of the optics. Rutherford Appleton Laboratory have developed a 3-side buttable, 20 millimeter x 20 millimeter CdTe-based detector with 250 micrometer square pixels (80 x 80 pixels) which achieves 1 kiloelectronvolt FWHM (Full-Width Half-Maximum) @ 60 kiloelectronvolts and gives full spectroscopy between 5 kiloelectronvolts and 200 kiloelectronvolts. An added advantage of these detectors is that they have a full-frame readout rate of 10 kilohertz. Working with NASA Goddard Space Flight Center and Marshall Space Flight Center, 4 of these 1 millimeter-thick CdTe detectors are tiled into a 2 x 2 array for use at the focal plane of a balloon-borne hard-x-ray telescope, and a similar configuration could be suitable for astrophysics and solar space-based missions. This effort encompasses the fabrication and testing of flight-suitable front-end electronics and calibration of the assembled detector arrays. We explain the operation of the pixelated ASIC readout and measurements, front-end electronics development, preliminary X-ray imaging and spectral performance, and plans for full calibration of the detector assemblies. Work done in conjunction with the NASA Centers is funded through the NASA Science Mission Directorate Astrophysics Research and Analysis Program.

  1. Hard-X-Ray/Soft-Gamma-Ray Imaging Sensor Assembly for Astronomy

    Science.gov (United States)

    Myers, Richard A.

    2008-01-01

    An improved sensor assembly has been developed for astronomical imaging at photon energies ranging from 1 to 100 keV. The assembly includes a thallium-doped cesium iodide scintillator divided into pixels and coupled to an array of high-gain avalanche photodiodes (APDs). Optionally, the array of APDs can be operated without the scintillator to detect photons at energies below 15 keV. The array of APDs is connected to compact electronic readout circuitry that includes, among other things, 64 independent channels for detection of photons in various energy ranges, up to a maximum energy of 100 keV, at a count rate up to 3 kHz. The readout signals are digitized and processed by imaging software that performs "on-the-fly" analysis. The sensor assembly has been integrated into an imaging spectrometer, along with a pair of coded apertures (Fresnel zone plates) that are used in conjunction with the pixel layout to implement a shadow-masking technique to obtain relatively high spatial resolution without having to use extremely small pixels. Angular resolutions of about 20 arc-seconds have been measured. Thus, for example, the imaging spectrometer can be used to (1) determine both the energy spectrum of a distant x-ray source and the angular deviation of the source from the nominal line of sight of an x-ray telescope in which the spectrometer is mounted or (2) study the spatial and temporal development of solar flares, repeating - ray bursters, and other phenomena that emit transient radiation in the hard-x-ray/soft- -ray region of the electromagnetic spectrum.

  2. Automated finishing of diamond turned dies for hard x-ray and EUV optics replication

    Science.gov (United States)

    Beaucamp, Anthony T. H.; Namba, Yoshiharu; Freeman, Richard R.

    2012-10-01

    Ultra-precision diamond turning can deliver very accurate form, often less than 100nm P-V. A possible manufacturing method for thin Wolter type-1 mirrors in hard X-ray space telescopes thus involves generating electroless nickel plated mandrels by diamond turning, before coating them with a reflective film and substrate. However, the surface texture after turning falls far short from the requirements of X-ray and EUV applications. The machining marks need to be removed, with hand polishing still widely employed. There is thus a compelling need for automated finishing of turned dies. A two step finishing method is presented that combines fluid jet and precessed bonnet polishing on a common 7-axis CNC platform. This method is capable of finishing diamond turned electroless nickel plated dies down to 0.28nm rms roughness, while deterministically improving form error down to 30nm P-V. The fluid jet polishing process, which consists of pressurizing water and abrasive particles for delivery through a nozzle, has been specially optimized with a newly designed slurry delivery unit and computer simulations, to remove diamond turning marks without introducing another waviness signature. The precessed bonnet polishing method, which consists of an inflated membrane rotated at an angle from the local normal to the surface and controlled by geometrical position relative to the work-piece, is subsequently employed with a novel control algorithm to deliver scratch-free surface roughness down to 0.28 nm rms. The combination of these two deterministic processes to finish aspheric and freeform dies promises to unlock new frontiers in X-ray and EUV optics fabrication.

  3. Hard X-ray Flares from Massive Black Holes and Proposed Surveys to EXIST

    Science.gov (United States)

    Grindlay, Jonathan E.; EXIST Team

    2010-03-01

    Flaring and short timescale variability are signatures of accreting black holes, from stellar to supermassive scales. We present Swift/BAT results from our ongoing BAT Slew Survey (BATSS; Copete, Grindlay et al 2010) that point to a surprisingly bright and new signature of AGN variability (Copete and Grindlay 2010, in preparation). As exciting as this is, it also points to an even richer domain for studies of the variability and associated physics of AGN and their SMBHs and jets, all of which are needed to understand flaring that relate to mergers and tidal disruptions by SMBHs. I discuss other high energy surveys, either planned or proposed, and their efficacy at revealing the sources and mechanisms of SMBH variability. The Energetic X-ray Imaging Survey Telescope (EXIST) has been proposed to Astro2010 as a very sensitive full-sky imaging, 3hour cadence, hard X-ray (5-600 keV) survey with rapid soft X-ray (0.1 - 10 keV) and uv-optical-IR (0.3 - 2.3microns) high sensitivity imaging and spectroscopic followup. It would trigger on a vast variety of AGN flares, including a predicted rate of 10-30 Tidal Disruption Events (TDEs) per year from EXIST detection could alert a LISA detection. Of interest to this session on gravitational wave signatures of black holes is the large number of short GRBs that EXIST would detect and precisely locate as well as measure redshifts for, from the very sensitive on board cooled 1.1m IR telescope. Those within the 300 Mpc detection radius of Advanced LIGO would enable a gravitational wave detection of the merging neutron star pair, or neutron star - black hole binary, and resultant stellar mass BH formation, which are the likely cause of most short GRBs.

  4. NuSTAR Hard X-Ray Observation of a Sub-A Class Solar Flare

    Energy Technology Data Exchange (ETDEWEB)

    Glesener, Lindsay [School of Physics and Astronomy, University of Minnesota, Minneapolis (United States); Krucker, Säm; Hudson, Hugh [Space Sciences Laboratory, University of California at Berkeley, Berkeley (United States); Hannah, Iain G. [SUPA School of Physics and Astronomy, University of Glasgow, Glasgow (United Kingdom); Grefenstette, Brian W. [Cahill Center for Astrophysics, California Institute of Technology, Pasadena (United States); White, Stephen M. [Air Force Research Laboratory, Albuquerque (United States); Smith, David M.; Marsh, Andrew J. [Santa Cruz Institute of Particle Physics and Department of Physics, University of California at Santa Cruz, Santa Cruz (United States)

    2017-08-20

    We report a Nuclear Spectroscopic Telescope Array ( NuSTAR ) observation of a solar microflare, SOL2015-09-01T04. Although it was too faint to be observed by the GOES X-ray Sensor, we estimate the event to be an A0.1 class flare in brightness. This microflare, with only ∼5 counts s{sup −1} detector{sup −1} observed by the Reuven Ramaty High Energy Solar Spectroscopic Imager ( RHESSI ), is fainter than any hard X-ray (HXR) flare in the existing literature. The microflare occurred during a solar pointing by the highly sensitive NuSTAR astrophysical observatory, which used its direct focusing optics to produce detailed HXR microflare spectra and images. The microflare exhibits HXR properties commonly observed in larger flares, including a fast rise and more gradual decay, earlier peak time with higher energy, spatial dimensions similar to the RHESSI microflares, and a high-energy excess beyond an isothermal spectral component during the impulsive phase. The microflare is small in emission measure, temperature, and energy, though not in physical size; observations are consistent with an origin via the interaction of at least two magnetic loops. We estimate the increase in thermal energy at the time of the microflare to be 2.4 × 10{sup 27} erg. The observation suggests that flares do indeed scale down to extremely small energies and retain what we customarily think of as “flare-like” properties.

  5. Quantitative spectromicroscopy from inelastically scattered photoelectrons in the hard X-ray range

    Energy Technology Data Exchange (ETDEWEB)

    Renault, O., E-mail: olivier.renault@cea.fr; Zborowski, C.; Risterucci, P. [Univ. Grenoble Alpes, F-38000 Grenoble, France and CEA, LETI, MINATEC Campus, F-38054 Grenoble (France); Wiemann, C.; Schneider, C. M. [Peter Grünberg Institute (PGI-6) and JARA-FIT, Research Center Jülich, D-52425 Jülich (Germany); Grenet, G. [Institut des Nanotechnologies de Lyon, Ecole Centrale, 69134 Ecully Cedex (France); Tougaard, S. [Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, DK-5230 Odense M (Denmark)

    2016-07-04

    We demonstrate quantitative, highly bulk-sensitive x-ray photoelectron emission microscopy by analysis of inelastically scattered photoelectrons in the hard X-ray range, enabling elemental depth distribution analysis in deeply buried layers. We show results on patterned structures used in electrical testing of high electron mobility power transistor devices with an epitaxial Al{sub 0.25}Ga{sub 0.75}N channel and a Ti/Al metal contact. From the image series taken over an energy range of up to 120 eV in the Ti 1s loss feature region and over a typical 100 μm field of view, one can accurately retrieve, using background analysis together with an optimized scattering cross-section, the Ti depth distribution from 14 nm up to 25 nm below the surface. The method paves the way to multi-elemental, bulk-sensitive 3D imaging and investigation of phenomena at deeply buried interfaces and microscopic scales by photoemission.

  6. A hard X-ray telescope/concentrator design based on graded period multilayer coatings

    DEFF Research Database (Denmark)

    Christensen, Finn Erland; Joensen, K. D.; Gorenstein, P.

    1995-01-01

    that it is smaller than roughly 1 mm. The design can be realized with foils as thin (≤0.4 mm) as used for ASCA and SODART or with closed, slightly thicker (∼1.0 mm) mirror shells as used for JET-X and XMM. The effect of an increase of the inner radius is quantified on the effective area for multilayered mirrors up...... of the telescope configuration provided that mirrors can be coated to an inner radius of 3 cm. Specifically we find that a change of focal length from 5 to 12 m affects the effective area by less than 10%. In addition the result is insensitive to the thickness of the individual mirror shell provided....../cm2/s/keV which demonstrates the great potential of this hard X-ray imaging telescope in the energy range up to 100 keV....

  7. Fermi GBM observations of the hard x-ray spectrum of Mrk 421

    Science.gov (United States)

    Hsu, Ching-Cheng; Connaughton, Valerie; Cherry, Michael L.; Rodi, James; Bhat, Narayana P.; Finger, Mark H.; Jenke, Peter; Wilson-Hodge, Colleen

    2014-08-01

    The Gamma-ray Burst Monitor (GBM) on Fermi uses the Earth Occultation technique for long-term monitoring of the hard X-ray/low energy gamma-ray sky. GBM produces multi-band light curves and spectra for known sources and transient outbursts in the 8 keV to 1 MeV energy range with its NaI detectors and up to 40 MeV with its BGO detectors. Mrk 421, one of the brightest and closest (z=0.031) established TeV blazars, is listed as a marginal detection in the GBM 3 year catalog. In this work, we report on five years of monitoring results for Mrk 421. Mrk421 was active between 2009 and 2010. The spectrum from the joint MAXI and GBM data in the range of 2-60 keV show clearly a curved spectrum fitted by a Log Polynomial function.

  8. Fresnel zone plate with apodized aperture for hard X-ray Gaussian beam optics.

    Science.gov (United States)

    Takeuchi, Akihisa; Uesugi, Kentaro; Suzuki, Yoshio; Itabashi, Seiichi; Oda, Masatoshi

    2017-05-01

    Fresnel zone plates with apodized apertures [apodization FZPs (A-FZPs)] have been developed to realise Gaussian beam optics in the hard X-ray region. The designed zone depth of A-FZPs gradually decreases from the center to peripheral regions. Such a zone structure forms a Gaussian-like smooth-shouldered aperture function which optically behaves as an apodization filter and produces a Gaussian-like focusing spot profile. Optical properties of two types of A-FZP, i.e. a circular type and a one-dimensional type, have been evaluated by using a microbeam knife-edge scan test, and have been carefully compared with those of normal FZP optics. Advantages of using A-FZPs are introduced.

  9. SuperHERO: the next generation hard x-ray HEROES telescope

    Science.gov (United States)

    Gaskin, Jessica A.; Christe, Steven D.; Elsner, Ronald F.; Kilaru, Kiranmayee; Ramsey, Brian D.; Seller, Paul; Shih, Albert Y.; Stuchlik, David W.; Swartz, Douglas A.; Tennant, Allyn F.; Weddendorf, Bruce; Wilson, Matthew D.; Wilson-Hodge, Colleen A.

    2014-07-01

    SuperHERO is a new high-resolution, Long Duration Balloon-capable, hard-x-ray (20-75 keV) focusing telescope for making novel astrophysics and heliophysics observations. The SuperHERO payload, currently in its proposal phase, is being developed jointly by the Astrophysics Office at NASA Marshall Space Flight Center and the Solar Physics Laboratory and the Wallops Flight Facility at NASA Goddard Space Flight Center. SuperHERO is a follow-on payload to the High Energy Replicated Optics to Explore the Sun (HEROES) balloon-borne telescope that recently flew from Fort Sumner, NM in September of 2013, and will utilize many of the same features. Significant enhancements to the HEROES payload will be made, including the addition of optics, novel solid-state multi-pixel CdTe detectors, integration of the Wallops Arc-Second Pointer and a significantly lighter gondola suitable for Long Duration Flights.

  10. Performance optimization for hard X-ray/soft gamma-ray detectors

    Science.gov (United States)

    Harrison, Fiona A.; Kahn, Steven M.; Hailey, Charles J.; Ziock, Klaus P.

    1990-01-01

    This paper discusses the optimization of the performance of imaging scintillation detectors used in the hard X-ray/soft gamma-ray (20-300) keV region of the spectrum. In these devices, absorption of an incident gamma-ray within an alkali halide crystal induces a scintillation light distribution which is centroided by an imaging photomultiplier tube mounted to the crystal. The ultimate imaging resolution is strongly affected by the detailed propagation of the scintillation light within the crystal and at the interface between the crystal and the phototube face plate. A number of refined techniques for preparing the scintillation crystals so as to optimize the imaging resolution have been investigated. The results indicate very good agreement with relatively simple models of the light propagation. It is shown that it is possible to achieve resolution consistent with the most optimistic models.

  11. Long duration balloon flights - A probe for deep hard X-ray astronomy investigation

    Science.gov (United States)

    Ubertini, P.

    An assessment is presented of the progress to date in hard X-ray astronomy, with attention to the use of long duration balloon flights carrying the sensitive and complex payloads needed for observations in the 15-300 keV range, and the comparative performance of balloon and satellite observational platforms. Both galactic and extragalactic balloon-borne observation results are considered. It is noted that the discovery of a cyclotron line emission at about 60 keV in the emission spectrum of Her-1 is of special significance, allowing direct measurement of the strong magnetic field surrounding the collapsed objects. Balloon observations are judged to be complementary to, rather than competitive with, satellite studies.

  12. An inexpensive spectroscopic beam monitor for hard X-ray synchrotron applications

    Energy Technology Data Exchange (ETDEWEB)

    Owens, A [Science Payload and Advanced Concepts Office, ESA/ESTEC, Postbus 299, 2200AG Noordwijk (Netherlands); Andersson, S [Science Payload and Advanced Concepts Office, ESA/ESTEC, Postbus 299, 2200AG Noordwijk (Netherlands); Hartog, R den [Science Payload and Advanced Concepts Office, ESA/ESTEC, Postbus 299, 2200AG Noordwijk (Netherlands); Quarati, F [Science Payload and Advanced Concepts Office, ESA/ESTEC, Postbus 299, 2200AG Noordwijk (Netherlands); Webb, A [HASYLAB at DESY, Notkestrasse 85, D 22607 Hamburg (Germany); Welter, E [HASYLAB at DESY, Notkestrasse 85, D 22607 Hamburg (Germany)

    2007-05-15

    We describe an inexpensive beam monitor for hard X-ray synchrotron applications which has good spectroscopic abilities and can operate without cooling. The device is centred on an inexpensive, commercial off-the-shelf, large area (1.2 x 1.2 mm{sup 2}) Si photodiode operated in single counting mode. Measurements carried out at the HASYLAB synchrotron research facility have shown that it is fully spectroscopic across the energy range 8 keV to 100 keV with a measured energy resolution of {approx} 1.2 keV FWHM at room temperature. The measured resolutions were found to be the same under pencil-beam and full-area illumination, indicating uniform crystallinity and stoichiometry of the bulk. The low cost, simplicity and performance of the detector make it suitable for a wider range of applications, e.g., in undergraduate laboratory experiments.

  13. Depth-resolved X-ray residual stress analysis in PVD (Ti, Cr) N hard coatings

    CERN Document Server

    Genzel, C

    2003-01-01

    Physical vapour deposition (PVD) of thin hard coatings on TiN basis is usually performed at rather low temperatures (T sub D < 500 C) far from thermal equilibrium, which leads to high intrinsic residual stresses in the growing film. In contrast to the extrinsic thermal residual stresses which can easily be estimated from the difference of the coefficients of thermal expansion between the substrate and the coating, a theoretical prediction of the intrinsic residual stresses is difficult, because their amount as well as their distribution within the film depend in a very complex way on the deposition kinetics. By the example of strongly fibre-textured PVD (Ti, Cr)N coatings which have been prepared under defined variation of the deposition parameters in order to adjust the residual stress distribution within the coatings, the paper compares different X-ray diffraction techniques with respect to their applicability for detecting residual stresses which are non-uniform over the coating thickness. (orig.)

  14. Hard X-ray texture measurements with an on-line image plate detector

    CERN Document Server

    Wcislak, L; Tschentscher, T; Klein, H; Bunge, H J

    2001-01-01

    An instrument for diffraction texture measurements in polycrystalline bulk materials using hard X-ray photons from the wiggler beamline BW5 at HASYLAB is described. High-energy photons in the 100 keV regime enable high penetration power in medium-to-high Z materials and the use of Laue diffraction geometry in combination with a two-dimensional area detector allows fast and convenient data collection. Determination of quantitative, high-resolution pole figures with a better angular resolution of 0.1 deg. is attained by the instrument. Profile analysis of the diffraction pattern parameters for each (h k l)-reflection thus provides, in addition to texture data, information about other microstructural quantities, e.g. lattice strain.

  15. An inexpensive spectroscopic beam monitor for hard X-ray synchrotron applications

    CERN Document Server

    Owens, A; Den Hartog, R; Quarati, F; Webb, A; Welter, E; HASYLAB at DESY, Hamburg, Germany

    2007-01-01

    We describe an inexpensive beam monitor for hard X-ray synchrotron applications which has good spectroscopic abilities and can operate without cooling. The device is centred on an inexpensive, commercial off-the-shelf, large area (1.2 × 1.2 mm2) Si photodiode operated in single counting mode. Measurements carried out at the HASYLAB synchrotron research facility have shown that it is fully spectroscopic across the energy range 8 keV to 100 keV with a measured energy resolution of ~ 1.2 keV FWHM at room temperature. The measured resolutions were found to be the same under pencil-beam and full-area illumination, indicating uniform crystallinity and stoichiometry of the bulk. The low cost, simplicity and performance of the detector make it suitable for a wider range of applications, e.g., in undergraduate laboratory experiments.

  16. Resolving the Crab Nebula with Direct Hard X-Ray Imaging

    Science.gov (United States)

    Swartz, Douglas A.; Ramsey, Brian D.; Tennant, Allyn F.; Dietz, Kurtis L.; Apple, Jeff A.; Gaskin, Jessica A.; Weisskopf, Martin

    2008-01-01

    We report the first direct hard (25--60 keV) X-ray imaging observation of the Crab Nebula that resolves structure to approximately 0.25 pc. The observation was performed over a 1.4 hour period during a balloon flight from Ft. Sumner, NM, on 2007 May 27. The source was detected in the energy band above the atmospheric cutoff at approx.25 keV and below the mirror graze angle cutoff at approx.60 keV. The image shows elongation about 25 degrees E of N in the direction along the plane of the torus (and perpendicular to the jet axis) with a slight surface-brightness enhancement NE of the pulsar. The spectrum within a 1.7 arcminute radius region centered on the Crab pulsar can be fitted with a Gamma=2 power law absorbed by an atmospheric column consistent with the balloon altitude at the time of observation.

  17. Kinetic simulations of core-hole relaxation in bulk material irradiated by hard X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Ziaja, Beata [Centre for Free-Electron Laser Science, DESY, Notkestrasse 85, Hamburg 22607 (Germany); Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Krakow (Poland); Saxena, Vikrant; Son, Sang-Kil; Medvedev, Nikita [Centre for Free-Electron Laser Science, DESY, Notkestrasse 85, Hamburg 22607 (Germany); Stransky, Michal [Department of Radiation and Chemical Physics, Academy of Sciences of the Czech Republic, Na Slovance 2, 182 21 Prague (Czech Republic); Woloncewicz, Bianka [Faculty of Mathematics, Physics and Informatics, University of Gdansk, ul. Wita Stwosza 57, 80-952 Gdansk (Poland); Barbrel, Benjamin [Center for Intense Lasers and Applications, University of Bordeaux 1, 351 Cours de la Liberation, F-33405 Talence (France)

    2016-07-01

    Irradiation of bulk material by hard X-rays creates a non-equilibrium state characterized by the presence of core-hole states taking complicated relaxation paths towards ground state configurations. This relaxation process involves a large number of active configurations even in case of moderately heavy atoms (e.g., 1323 configurations for argon). It is computationally challenging to follow them, even with a kinetic approach which is otherwise an efficient approach for simulation of irradiated bulk material. Here, we propose a simplified approach which limits the number of active configurations by restricting the sample relaxation to the predominant relaxation paths. We test its reliability, by performing the full calculation for carbon, and comparing it with the simplified scheme.

  18. HERO: Program Status and Fist Images from a Balloon-Borne Focusing Hard-X-ray Telescope

    Science.gov (United States)

    Ramsey, B. D.; Alexander, C. D.; Apple, J. A.; Benson, C. M.; Dietz, K. L.; Elsner, R. F.; Engelhaupt. D. E.; Ghosh, K. K.; Kolodziejczak, J. J.; ODell, S. L.; hide

    2001-01-01

    HERO is a balloon payload featuring shallow-graze angle replicated optics for hard-x-ray imaging. When completed, the instrument will offer unprecedented sensitivity in the hard-x-ray region, giving thousands of sources to choose from for detailed study on long flights. A recent proof-of-concept flight captured the first hard-x-ray focused images of the Crab Nebula, Cygnus X-1 and GRS 1915+105. Full details of the HERO program are presented, including the design and performance of the optics, the detectors and the gondola. Results from the recent proving flight are discussed together with expected future performance when the full science payload is completed.

  19. Development of Multilayer Coatings for Hard X-Ray Optics at NASA Marshall Space Flight Center

    Science.gov (United States)

    Gurgew, Danielle N.; Broadway, David M.; Ramsey, Brian; Gregory, Don

    2017-01-01

    Broadband X-ray multilayer coatings are under development at NASA MSFC for use on future astronomical X-ray telescopes. Multilayer coatings deposited onto the reflecting surfaces of X-ray optics can provide a large bandpass enabling observations of higher energy astrophysical objects and phenomena.

  20. Hard X-ray photoelectron spectroscopy of bulk and thin films of Heusler compounds

    Energy Technology Data Exchange (ETDEWEB)

    Kozina, Xeniya

    2012-03-26

    X-ray photoemission spectroscopy (XPS) is one of the most universal and powerful tools for investigation of chemical states and electronic structures of materials. The application of hard X-rays increases the inelastic mean free path of the emitted electrons within the solid and thus makes hard X-ray photoelectron spectroscopy (HAXPES) a bulk sensitive probe for solid state research and especially a very effective nondestructive technique to study buried layers. This thesis focuses on the investigation of multilayer structures, used in magnetic tunnel junctions (MTJs), by a number of techniques applying HAXPES. MTJs are the most important components of novel nanoscale devices employed in spintronics. The investigation and deep understanding of the mechanisms responsible for the high performance of such devices and properties of employed magnetic materials that are, in turn, defined by their electronic structure becomes feasible applying HAXPES. Thus the process of B diffusion in CoFeB-based MTJs was investigated with respect to the annealing temperature and its influence on the changes in the electronic structure of CoFeB electrodes that clarify the behaviour and huge TMR ratio values obtained in such devices. These results are presented in chapter 6. The results of investigation of the changes in the valence states of buried off-stoichiometric Co{sub 2}MnSi electrodes were investigated with respect to the Mn content {alpha} and its influence on the observed TMR ratio are described in chapter 7. Magnetoelectronic properties such as exchange splitting in ferromagnetic materials as well as the macroscopic magnetic ordering can be studied by magnetic circular dichroism in photoemission (MCDAD). It is characterized by the appearance of an asymmetry in the photoemission spectra taken either from the magnetized sample with the reversal of the photon helicity or by reversal of magnetization direction of the sample when the photon helicity direction is fixed. Though

  1. Determination of electronic and atomic properties of surface, bulk and buried interfaces: Simultaneous combination of hard X-ray photoelectron spectroscopy and X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Rubio-Zuazo, J., E-mail: rubio@esrf.fr [SpLine, Spanish CRG BM25 Beamline at the ESRF, ESRF, B.P. 220, F-38043 Grenoble (France); Instituto de Ciencia de Materiales de Madrid, ICMM, CSIC, Cantoblanco, E-28049 Madrid (Spain); Castro, G.R. [SpLine, Spanish CRG BM25 Beamline at the ESRF, ESRF, B.P. 220, F-38043 Grenoble (France); Instituto de Ciencia de Materiales de Madrid, ICMM, CSIC, Cantoblanco, E-28049 Madrid (Spain)

    2013-10-15

    Highlights: •We have developed a novel and exceptional tool for non-destructive characterization of bulk and buried interfaces that combine XRD and HAXPES. •We studied the correlation between the atomic, electronic and transport properties of oxygen deficient manganite thin films. •The diffraction data showed a cooperative tilt of the MnO{sub 6} block along the out-of-plane direction. •We shown the absence of the conventional basal plane rotation for the oxygen deficient samples. -- Abstract: Hard X-ray photoelectron spectroscopy (HAXPES) is a powerful novel emerging technique for bulk compositional, chemical and electronic properties determination in a non-destructive way. It benefits from the exceptionally large escape depth of high kinetic energy photoelectrons enabling the study of bulk and buried interfaces up to several tens of nanometres depth. Its advantage over conventional XPS is based on the long mean free path of high kinetic energetic photoelectrons. Using the advantage of tuneable X-ray radiation provided by synchrotron sources the photoelectron kinetic energy, i.e. the information depth can be changed and consequently electronic and compositional depth profiles can be obtained. The combination of HAXPES with an atomic structure sensitive technique, as X-ray diffraction, opens a new research field with great potential for many systems in which their electronic properties are intimately linked to their crystallographic structure. At SpLine, the Spanish CRG Beamline at the European Synchrotron Radiation Facility (ESRF) we have developed a novel and exceptional set-up that combine grazing incidence X-ray diffraction (GIXRD) and HAXPES. Both techniques can be operated simultaneously on the same sample and using the same excitation source. The set-up includes a heavy 2S+3D diffractometer and UHV chamber equipped with an electrostatic analyzer. The UHV chamber has also MBE evaporation sources, an ion gun, a LEED optic, a sample heating and cooling

  2. Chandra and Suzaku Follow-up Observations of Hard X-ray Selected AGN in the UDIS

    Science.gov (United States)

    Virani, Shanil N.; Urry, C. M.; Treister, E.; Schawinski, K.; Maccarone, T. J.; Beckmann, V.; Coppi, P.

    2010-01-01

    We carried out a 3 Megasecond Ultra-Deep INTEGRAL Survey (UDIS) to define a faint hard X-ray-selected AGN sample, unbiased by even the heaviest obscuration. The space density of AGN that are Compton-thick (NH>1024 cm-2) remains unknown even though it has been suggested they could nearly equal the space density of less obscured supermassive black holes. In the Ultra-Deep INTEGRAL Survey, one of the deepest surveys of the hard X-ray sky ever done, we detect 15 AGN some of which are detected in the hard X-rays for the first time. In order to measure the obscuration and the high-energy reflection component for these sources, we obtained follow-up observations with Chandra and Suzaku. Here we present X-ray spectra for all 15 AGN, including the inferred distribution of absorbing column densities. Measurement and modeling of the X-ray background provides at best an integral and degenerate constraint on AGN populations, which only weakly constrains the most obscured objects as they make only a minor contribution to the background. Direct detection of heavily obscured objects by surveys like UDIS is thus the only way to obtain a true census of their population.

  3. NuSTAR detection of 4s Hard X-ray Lags from the Accreting Pulsar GS 0834-430

    DEFF Research Database (Denmark)

    Bachetti, Matteo; Miyasaka, Hiromasa; Harrison, Fiona

    2014-01-01

    The NuSTAR hard X-ray telescope observed the transient Be/X-ray binary GS 0834􀀀430 during its 2012 outburst. The source is detected between 3 – 79 keV with high statistical significance, and we were able to perform very accurate spectral and timing analysis. The phase-averaged spectrum....... The pulse profile can be modeled with a double Gaussian and shows a strong and smooth hard lag of up to 0.3 cycles in phase, or about 4s between the pulse at ∼ 3 and >∼ 30 keV. This is the first report of such a strong lag in high-mass X-ray binary (HMXB) pulsars. Previously reported lags have been...

  4. Generation of isolated single attosecond hard X-ray pulse in enhanced self-amplified spontaneous emission scheme.

    Science.gov (United States)

    Kumar, Sandeep; Kang, Heung-Sik; Kim, Dong Eon

    2011-04-11

    The generation of isolated attosecond hard x-ray pulse has been studied under the enhanced self-amplified spontaneous emission (ESASE) scheme with the density and energy modulation of an electron bunch. It is demonstrated in simulation that an isolated attosecond hard x-ray pulse of a high contrast ratio can be produced by adjusting a driver laser wavelength and the energy distribution of an electron bunch. An isolated attosecond pulse of ~146 attosecond full-width half-maximum (FWHM) at 0.1 nm wavelength is obtained with a saturation length of 34 meter for the electron beam parameters of Korean X-ray Free Electron laser. © 2011 Optical Society of America

  5. Numerical simulations of the hard X-ray pulse intensity distribution at the Linac Coherent Light Source.

    Science.gov (United States)

    Pardini, Tom; Aquila, Andrew; Boutet, Sébastien; Cocco, Daniele; Hau-Riege, Stefan P

    2017-07-01

    Numerical simulations of the current and future pulse intensity distributions at selected locations along the Far Experimental Hall, the hard X-ray section of the Linac Coherent Light Source (LCLS), are provided. Estimates are given for the pulse fluence, energy and size in and out of focus, taking into account effects due to the experimentally measured divergence of the X-ray beam, and measured figure errors of all X-ray optics in the beam path. Out-of-focus results are validated by comparison with experimental data. Previous work is expanded on, providing quantitatively correct predictions of the pulse intensity distribution. Numerical estimates in focus are particularly important given that the latter cannot be measured with direct imaging techniques due to detector damage. Finally, novel numerical estimates of improvements to the pulse intensity distribution expected as part of the on-going upgrade of the LCLS X-ray transport system are provided. We suggest how the new generation of X-ray optics to be installed would outperform the old one, satisfying the tight requirements imposed by X-ray free-electron laser facilities.

  6. Experimental study on hard X-rays emitted from metre-scale negative discharges in air

    CERN Document Server

    Kochkin, P O; Ebert, Ute

    2015-01-01

    We investigate the development of meter long negative discharges and focus on their X-ray emissions. We describe appearance, timing and spatial distribution of the X-rays. They appear in bursts of nanosecond duration mostly in the cathode area. The spectrum can be characterized by an exponential function with 200 keV characteristic photon energy. With nanosecond-fast photography we took detailed images of the pre-breakdown phenomena during the time when X-rays were registered. We found bipolar discharge structures, also called "pilot systems", in the vicinity of the cathode. As in our previous study of X-rays from positive discharges, we correlate the X-ray emission with encounters between positive and negative streamers. We suggest that a similar process is responsible for X-rays generated by lightning leaders.

  7. PheniX: A New Vision for the Hard X-ray Sky

    Science.gov (United States)

    Roques, Jean-Pierre; Jourdain, Elisabeth; Bassani, Loredana; Bazzano, Angela; Belmont, Renaud; Bird, A. J.; Caroli, E.; Chauvin, M.; Clark, D.; Gehrels, N.; hide

    2012-01-01

    We are proposing a mission devoted to high energy X-ray astronomy that is based on a focusing telescope operating in the 1-200 keV energy range but optimized for the hard X-ray range. The main scientific topics concern: Physics of compact objects: The proximity of compact objects provides a unique laboratory to study matter and radiation in extreme conditions of temperature and density in strong gravitational environment. The emission of high energy photons from these objects is far from being understood. The unprecedented sensitivity in the high energy domain will allow a precise determination of the non-thermal processes at work in the vicinity of compact objects. The full 1-200 keV energy coverage will be ideal to disentangle the emission processes produced in the spacetime regions most affected by strong-gravity, as well as the physical links: disk-thermal emission-iron line-comptonisation-reflection-non-thermal emission-jets. Neutron stars-magnetic field-cyclotron lines: Time resolved spectroscopy (and polarimetry) at ultra-high sensitivity of AXP, milliseconds pulsars and magnetars will give new tools to study the role of the synchrotron processes at work in these objects. Cyclotron lines-direct measurement of magnetic filed-equation of state constraints-short bursts-giant flares could all be studied with great details. AGN: The large sensitivity improvement will provide detailed spectral properties of the high energy emission of AGN's. This will give a fresh look to the connection between accretion and jet emission and will provide a new understanding of the physical processes at work. Detection of high-redshift active nuclei in this energy range will allow to introduce an evolutionary aspect to high-energy studies of AGN, probing directly the origin of the Cosmic X-ray Background also in the non-thermal range (> 20 keV). Element formation-Supernovae: The energy resolution achievable for this mission (<0.5 keV) and a large high energy effective area are

  8. NuSTAR Hard X-Ray Observation of the Gamma-Ray Binary Candidate HESS J1832-093

    Science.gov (United States)

    Mori, Kaya; Gotthelf, E. V.; Hailey, Charles J.; Hord, Ben J.; de Oña Wilhelmi, Emma; Rahoui, Farid; Tomsick, John A.; Zhang, Shuo; Hong, Jaesub; Garvin, Amani M.; Boggs, Steven E.; Christensen, Finn E.; Craig, William W.; Harrison, Fiona A.; Stern, Daniel; Zhang, William W.

    2017-10-01

    We present a hard X-ray observation of the TeV gamma-ray binary candidate HESS J1832-093, which is coincident with the supernova remnant G22.7-0.2, using the Nuclear Spectroscopic Telescope Array. Non-thermal X-ray emission from XMMU J183245-0921539, the X-ray source associated with HESS J1832-093, is detected up to ˜30 keV and is well-described by an absorbed power-law model with a best-fit photon index {{Γ }}=1.5+/- 0.1. A re-analysis of archival Chandra and XMM-Newton data finds that the long-term X-ray flux increase of XMMU J183245-0921539 is {50}-20+40 % (90% C.L.), much less than previously reported. A search for a pulsar spin period or binary orbit modulation yields no significant signal to a pulse fraction limit of {f}ppower spectrum to suggest active accretion from a binary system. While further evidence is required, we argue that the X-ray and gamma-ray properties of XMMU J183245-0921539 are most consistent with a non-accreting binary generating synchrotron X-rays from particle acceleration in the shock formed as a result of the pulsar and stellar wind collision. We also report on three nearby hard X-ray sources, one of which may be associated with diffuse emission from a fast-moving supernova fragment interacting with a dense molecular cloud.

  9. 6 MeV storage ring dedicated to hard X-ray imaging and far-infrared ...

    Indian Academy of Sciences (India)

    ray imaging as well as far-infrared (FIR) spectroscopy. In spite of low electron energy, the 6 MeV MIRRORCLE generates hard X-rays ranging from 10 keV up to its electron energy and milliwatt order sub- millimetre range FIR rays.

  10. Hard X-ray emission clumps in the gamma-Cygni supernova remnant: An INTEGRAL-ISGRI view

    NARCIS (Netherlands)

    Bykov, A.M.; Krassilchtchikov, A.M.; Uvarov, Y.A.; Bloemen, H.; Chevalier, R.A.; Gustov, M.Y.; Hermsen, W.; Lebrun, F.; Lozinskaya, T.A.; Rauw, G.; Smirnova, T.V.; Sturner, S.J.; Swings, J.-P.; Terrier, R.; Toptygin, I.N.

    2004-01-01

    Spatially resolved images of the galactic supernova remnant G78.2+2.1 (gamma-Cygni) in hard X-ray energy bands from 25 keV to 120 keV are obtained with the IBIS-ISGRI imager aboard the International Gamma-Ray Astrophysics Laboratory INTEGRAL. The images are dominated by localized clumps of about ten

  11. Investigation on the Hard X-ray Radiations of the IR-T1 Tokamak Plasma: Electric and Magnetic Perspectives

    Science.gov (United States)

    Alipour, R.; Ghoranneviss, M.; Salar Elahi, A.

    2017-12-01

    In this experiment, the effect of magnetohydrodynamic (MHD) fluctuations in the hard X-ray radiation from the IR-T1 tokamak plasma is investigated. To reach this goal, the main parameters of plasma such as plasma current and loop voltage are measured. Also, the rake and poloidal Langmuir probes are used to calculate the radial and poloidal electric fields. To detect the hard X-ray radiation, a NaI-scintillator detector is used. To study on the MHD fluctuations, an array of 12 Mirnov coils is used. The obtained data are analyzed by using the singular value decomposition (SVD) algorithm. The wavelet spectrum of the dominant principal components of Mirnov coils is drawn. The results of wavelet and SVD analysis show that the hard X-ray radiation is increased with increasing the fluctuations of the dominant principal components (at the same time). It is also shown that the rate of hard X-ray radiation emitted from the tokamak plasma increased with increasing the MHD fluctuations. The energy of the system is wasted and reduced by these radiations. This an increase in the particle pressure of the plasma.

  12. SuperHERO: The Next Generation Hard X-Ray Focusing Telescope

    Science.gov (United States)

    Gaskin, Jessica; Wilson-Hodge, Colleen; Ramsey, Brian; Elsner, Ronald; Tennant, Allyn F.; Kilaru, Kiranmayee; Swartz, Douglas A.; Christe, Steven; Shih, Albert Y.; Baganoff, Frederick K.; Seller, Paul; Wilson, Matthew; Stuchlik, David

    2015-01-01

    SuperHERO is a balloon-borne hard x-ray (20-75 keV) telescope that couples high-angular resolution (~20 arcsecs) electroformed-nickel grazing incidence optics to state-of-the-art fine pixel-pitch (250 µm) Cadmium-Telluride detectors with a 6 m focal length. This telescope, currently in the proposal phase, will have the highest angular resolution of any hard x-ray telescope to date, and comparable energy resolution to that of the Nuclear Spectroscopic Telescope Array. The high angular resolution afforded by focusing optics is essential for mitigating source confusion in crowded fields, for direct imaging of extended sources on fine spatial scales, and for efficient observing through greatly-increased sensitivity. As such, the primary astronomical targets are the Galactic Center, pulsar-powered synchrotron nebulae and diffusive shock accelerated sites in supernova remnants. To facilitate solar observations, the SuperHERO detectors have a high processing rate of ~10 kHz over the entire 80x80 pixel array, or over 5M photons per second over the detector area. The current SuperHERO configuration has a total on-axis effective area of 145 cm2 at 30 keV and a field of view of ~7 arcmin FWHM at 30 keV (simulated). The optics, developed at NASA Marshall Space Flight Center, have significant flight heritage as similar mirrors have flown on balloon payloads, sounding rockets and a satellite mission. The detectors, developed at Rutherford Appleton Laboratory (RAL), utilize the novel HEXITEC Application Specific Integrated Circuit. RAL has been working on these and similar detectors for over a decade for applications ranging from medical to defense. NASA Goddard Space Flight Center, working with RAL and MSFC has been adapting these detectors for flight, with good progress. The telescope will reside on a carbon-composite frame that will integrate the Wallops Arc Second Pointer. This design will allow for Long Duration Balloon flights from Antarctica that can last up to 4 weeks

  13. LAMBDA 2M GaAs—A multi-megapixel hard X-ray detector for synchrotrons

    Science.gov (United States)

    Pennicard, D.; Smoljanin, S.; Pithan, F.; Sarajlic, M.; Rothkirch, A.; Yu, Y.; Liermann, H. P.; Morgenroth, W.; Winkler, B.; Jenei, Z.; Stawitz, H.; Becker, J.; Graafsma, H.

    2018-01-01

    Synchrotrons can provide very intense and focused X-ray beams, which can be used to study the structure of matter down to the atomic scale. In many experiments, the quality of the results depends strongly on detector performance; in particular, experiments studying dynamics of samples require fast, sensitive X-ray detectors. "LAMBDA" is a photon-counting hybrid pixel detector system for experiments at synchrotrons, based on the Medipix3 readout chip. Its main features are a combination of comparatively small pixel size (55 μm), high readout speed at up to 2000 frames per second with no time gap between images, a large tileable module design, and compatibility with high-Z sensors for efficient detection of higher X-ray energies. A large LAMBDA system for hard X-ray detection has been built using Cr-compensated GaAs as a sensor material. The system is composed of 6 GaAs tiles, each of 768 by 512 pixels, giving a system with approximately 2 megapixels and an area of 8.5 by 8.5 cm2. While the sensor uniformity of GaAs is not as high as that of silicon, its behaviour is stable over time, and it is possible to correct nonuniformities effectively by postprocessing of images. By using multiple 10 Gigabit Ethernet data links, the system can be read out at the full speed of 2000 frames per second. The system has been used in hard X-ray diffraction experiments studying the structure of samples under extreme pressure in diamond anvil cells. These experiments can provide insight into geological processes. Thanks to the combination of high speed readout, large area and high sensitivity to hard X-rays, it is possible to obtain previously unattainable information in these experiments about atomic-scale structure on a millisecond timescale during rapid changes of pressure or temperature.

  14. 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

  15. Progress toward a hard x-ray insertion device beam position monitor at the Advanced Photon Source.

    Energy Technology Data Exchange (ETDEWEB)

    Decker, G.; Den Hartog, P.; Singh, O.; Rosenbaum, G.; Univ. of Georgia

    2008-01-01

    Long-term pointing stability at synchrotron light sources using conventional rf-based particle beam position monitoring is limited by the mechanical stability of the pickup electrode assembly. Photoemission-based photon beam position monitors for insertion device beams suffer from stray radiation backgrounds and other gap- dependent systematic errors. To achieve the goal of 500-nanoradian peak-to-peak pointing stability over a one-week period, the development of a photon beam position detector sensitive only to hard X-rays (> several keV) using copper X-ray fluorescence has been initiated. Initial results and future plans are presented.

  16. Dense plasma focus PACO as a hard X-ray emitter: a study on the radiation source

    OpenAIRE

    Supán, L.; Guichón, S.; Milanese, Maria Magdalena; Niedbalski, Jorge Julio; Moroso, Roberto Luis; Acuña, H.; Malamud, Florencia

    2016-01-01

    The radiation in the X-ray range detected outside the vacuum chamber of the dense plasma focus (DPF) PACO, are produced on the anode zone. The zone of emission is studied in a shot-to-shot analysis, using pure deuterium as filling gas. We present a diagnostic method to determine the place and size of the hard X-ray source by image analysis of high density radiography plates. Fil: Supán, L.. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Insti...

  17. Experimental study on hard X-rays emitted from metre-scale negative discharges in air

    NARCIS (Netherlands)

    P.O. Kochkin (Pavlo); A. van Deursen (Arie); U. Ebert (Ute)

    2015-01-01

    htmlabstractWe investigate the development of metre long negative discharges and focus on their x-ray emissions. We describe appearance, timing and spatial distribution of the x-rays. They appear in bursts of nanosecond duration mostly in the cathode area. The spectrum can be characterized by an

  18. Reflectivity studies on a synchrotron radiation mirror in the hard X-ray regime

    CERN Document Server

    Keil, P; Novikov, D V; Hahn, U; Frahm, R

    2001-01-01

    The optical performance and roughness parameters of an X-ray mirror that was used for several years in a synchrotron radiation beamline are determined by studying its X-ray reflectivity and diffuse scattering behavior. These values are compared to the data derived from topographic measurements with an atomic force microscope (AFM).

  19. INTEGRAL discovered a new hard X-ray source: IGRJ17511-3057

    DEFF Research Database (Denmark)

    Baldovin, C.; Kuulkers, E.; Ferrigno, C.

    2009-01-01

    V, and 11-20 keV. The source flux is ~20 mCrab and the detection significance is 3 sigma in all bands. The best determined source position is RA: 267.811 DEC: -30.954 (J2000), with a 90% error radius of 2.0 arcmin. The combined IBIS/ISGRI and JEM-X spectrum in the 3-100 keV energy range is well described......During the latest observations of the Galactic Bulge monitoring (see ATel #438), carried out between 2009-09-12 03:21:34 and 2009-09-12 05:27:22 (UTC), INTEGRAL discovered a new bright hard X-ray source, which we designate IGRJ17511-3057. The source is detected in the INTEGRAL/IBIS mosaic image...... with a significance of 14 sigma in the 20-40 keV energy band, and 7 sigma in the 40-80 keV energy band. The corresponding count rates in these bands are 4.2+/0.3 cts/s (28 mCrab) and 1.8+/-0.3 cts/s (25 mCrab), respectively. The source is also detected in the JEM-X mosaic in the three energy bands 3-7 keV, 7-11 ke...

  20. Distributed seeding for narrow-line width hard x-ray free-electron lasers

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Dinh Cong [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Anisimov, Petr Mikhaylovich [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Buechler, Cynthia Eileen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lewellen, IV, John W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Marksteiner, Quinn R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-09-09

    We describe a new FEL line-narrowing technique called distributed seeding (DS), using Si(111) Bragg crystal monochromators to enhance the spectral brightness of the MaRIE hard X-ray freeelectron laser. DS differs from self-seeding in three important aspects. First, DS relies on spectral filtering of the radiation at multiple locations along the undulator, with a monochromator located every few power gain lengths. Second, DS performs filtering early in the exponential gain region before SASE spikes start to appear in the radiation longitudinal profile. Third, DS provides the option to select a wavelength longer than the peak of the SASE gain curve, which leads to improved spectral contrast of the seeded FEL over the SASE background. Timedependent Genesis simulations show the power-vs-z growth curves for DS exhibit behaviors of a seeded FEL amplifier, such as exponential growth region immediately after the filters. Of the seeding approaches considered, the two-stage DS spectra produce the highest contrast of seeded FEL over the SASE background and that the three-stage DS provides the narrowest linewidth with a relative spectral FWHM of 8 X 10-5 .

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-01-28

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

  2. The hard X-ray response of epitaxial GaAs detectors

    CERN Document Server

    Owens, A; Kraft, S; Peacock, A; Nenonen, S; Andersson, H

    2000-01-01

    We report on hard X-ray measurements with two epitaxial GaAs detectors of active areas 2.22 mm sup 2 and thicknesses 40 and 400 mu m at the ESRF and HASYLAB synchrotron research facilities. The detectors were fabricated using high-purity material and in spite of an order of magnitude difference in depletion depths, they were found to have comparable performances with energy resolutions at -45 deg. C of approx 1 keV fwhm at 7 keV rising to approx 2 keV fwhm at 200 keV and noise floors in the range 1-1.5 keV. At energies <30 keV, the energy resolution was dominated by leakage current and electromagnetic pick-up, while at the highest energies measured, the resolutions approach the expected Fano limit (e.g., approx 1 keV near 200 keV). Both detectors are remarkably linear, with average rms non-linearities of 0.2% over the energy range 10-60 keV, which, taken in conjunction with Monte-Carlo results indicate that charge collection efficiencies must be in excess of 98%. This is consistent with material science me...

  3. Strong magneto-chiral dichroism in a paramagnetic molecular helix observed by hard X-ray

    Science.gov (United States)

    Sessoli, Roberta; Boulon, Marie-Emmanuelle; Caneschi, Andrea; Mannini, Matteo; Poggini, Lorenzo; Wilhelm, Fabrice; Rogalev, Andrei

    2014-01-01

    Magneto-chiral dichroism (MχD) is a non-reciprocal, i. e. directional, effect observed in magnetised chiral systems featuring an unbalanced absorption of unpolarised light depending on the direction of the magnetisation. Despite the fundamental interest in a phenomenon breaking both parity and time reversal symmetries, MχD is one of the least investigated aspects of light-matter interaction because of the weakness of the effect in most reported experiments. Here we have exploited the element selectivity of hard X-ray radiation to investigate the magneto-chiral properties of enentiopure crsytals of two isostructural molecular helicoidal chains comprising Cobalt(II) and Manganese (II) ions, respectively. A strong magneto-chiral dichroism, with Kuhn asymmetry of the order of a few percent, has been observed in the Cobalt chain system, while it is practically absent for the Manganese derivative. The spectral features of the XMχD signal differ significantly from the natural and magnetic dichroic contributions and have been here rationalized using the simple multipolar expansion of matter-radiation interaction. PMID:25729401

  4. SuperHERO: Design of a New Hard X-Ray Focusing Telescope

    Science.gov (United States)

    Gaskin, Jessica; Elsner, Ronald; Ramsey, Brian; Wilson-Hodge, Colleen; Tennant, Allyn; Christe, Steven; Shih, Albert; Kiranmayee, Kilaru; Swartz, Douglas; Seller, Paul; hide

    2015-01-01

    SuperHERO is a hard x-ray (20-75 keV) balloon-borne telescope, currently in its proposal phase, that will utilize high angular-resolution grazing-incidence optics, coupled to novel CdTe multi-pixel, fine-pitch (250 micrometers) detectors. The high-resolution electroformed-nickel, grazing-incidence optics were developed at MSFC, and the detectors were developed at the Rutherford Appleton Laboratory in the UK, and are being readied for flight at GSFC. SuperHERO will use two active pointing systems; one for carrying out astronomical observations and another for solar observations during the same flight. The telescope will reside on a light-weight, carbon-composite structure that will integrate the Wallops Arc Second Pointer into its frame, for arcsecond or better pointing. This configuration will allow for Long Duration Balloon flights that can last up to 4 weeks. This next generation design, which is based on the High Energy Replicated Optics (HERO) and HERO to Explore the Sun (HEROES) payloads, will be discussed, with emphasis on the core telescope components.

  5. INTEGRAL discovery of a new hard X-ray transient: IGR J17177-3656

    DEFF Research Database (Denmark)

    Frankowski, A.; Ferrigo, C.; Bozzo, E.

    2011-01-01

    We report on the discovery of a new transient source, IGR J17177-3656, detected during the INTEGRAL observation performed from 2011-03-15 09:23 to 2011-03-15 22:42 UT. The source was detected by IBIS/ISGRI at a significance level of 13 and 9 standard deviations, in the 20-40 keV and 40-80 keV ene...... = 1.2e22 cm-2). We encourage multiwavelength observations to investigate the nature of the system, which has the typical characteristics of either an X-ray transient in an initial hard state or a transient highly absorbed source.......We report on the discovery of a new transient source, IGR J17177-3656, detected during the INTEGRAL observation performed from 2011-03-15 09:23 to 2011-03-15 22:42 UT. The source was detected by IBIS/ISGRI at a significance level of 13 and 9 standard deviations, in the 20-40 keV and 40-80 ke...

  6. Preparation of bent crystals as high-efficiency optical elements for hard x-ray astronomy

    Science.gov (United States)

    Buffagni, Elisa; Ferrari, Claudio; Rossi, Francesca; Marchini, Laura; Zappettini, Andrea

    2012-05-01

    Curved crystals, instead of flat mosaic crystals, can be used as optical elements of a Laue lens for hard x- and gamma-ray astronomy to increase the diffraction efficiency. We propose to achieve the bending of the crystals by a controlled surface damaging, which introduces defects in a layer of few tens nanometers in thickness undergoing a highly compressive strain. Several oriented silicon and gallium arsenide wafer crystals have been treated. The local and mean curvature radii of each sample have been determined by means of high resolution x-ray diffraction measurements in Bragg condition at low energy (8 keV). Silicon samples showed spherical curvatures, whereas GaAs-treated samples evidenced elliptical curvatures with major axes corresponding to the crystallographic directions. Curvature radii between 3 and 70 m were easily obtained in wafers of different thicknesses. The characterization of GaAs samples performed in Laue geometry at gamma-ray energy of 120 keV confirmed the increase of the diffraction efficiency in the bent crystals.

  7. Correlation of electron beams and hard x-ray emissions in ISTTOK Tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Jakubowski, L.; Malinowski, K.; Sadowski, M.J.; Zebrowski, J.; Rabinski, M.; Jakubowski, M.J. [National Centre for Nuclear Research (NCBJ), Otwock (Poland); Plyusnin, V.V.; Fernandes, H.; Silva, C.; Duarte, P. [Association Euratom/IST, Instituto de Plasmas e Fusao Nuclear, Instituto Superior Tecnico, Lisboa (Portugal)

    2013-11-15

    The paper reports on experimental studies of electron beams in the ISTTOK tokamak, those were performed by means of an improved four-channel detector. The Cherenkov-type detector measuring head was equipped with four radiators made of two types of alumina-nitrate (AlN) poly-crystals: machinable and translucent ones, both of 10 mm in diameter and 2.5 mm in thickness. The movable support that enabled the whole detectors to be placed inside the tokamak vacuum chamber, at chosen positions along the ISTTOK minor radius. Since the electron energy distribution is one of the most important characteristics of tokamak plasmas, the main aim of the study was to perform estimations of an energy spectrum of the recorded electrons. For this purpose the radiators were coated with molybdenum (Mo) layers of different thickness. The technique based on the use of Cherenkov-type detectors enabled the detection of fast electrons (of energy above 66 keV) and determination of their spatial and temporal characteristics in the ISTTOK experiment. Measurements of hard X-rays (HXR), which were emitted during ISTTOK discharges, have also been performed. Particular attention was paid to the correlation measurements of HXR pulses with run-away electron beams. (copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  8. The host galaxies of ultra hard X-ray selected AGN

    Science.gov (United States)

    Koss, Michael J.

    One of the great mysteries surrounding active galactic nuclei (AGN) is their triggering mechanism. Since the discovery that almost all massive galaxies host nuclear supermassive black holes, it has become clear that a trigger mechanism is required to 'turn on' and continue to fuel the central black hole. While it is established that accretion processes are responsible for the energy emitted, the source of the accreting material is still controversial. Furthermore, the energy input from phases of black hole growth is thought to be a key regulator in the formation of galaxies and the establishment of various scaling relations. Theorists often invoke galaxy mergers as the violent mechanism to drive gas into the central regions and ignite luminous quasars, but among more common moderate luminosity AGN, there has been great controversy whether secular processes or mergers dominate AGN fueling. A survey in the ultra hard X-ray band (14--195 keV) is an important new way to answer the fundamental question of AGN fueling. This method is independent of selection effects such as dust extinction and obscuration that plague surveys at other wavelengths because of the ability of the primary continuum to easily pass through large columns of obscuring gas and dust (2 keV) imaging.

  9. The First Focused Hard X-Ray Images of the Sun with NuSTAR

    Science.gov (United States)

    Grefenstette, Brian W.; Glesener, Lindsay; Kruckner, Sam; Hudson, Hugh; Hannah, Iain G.; Smith, David M.; Vogel, Julia K.; White, Stephen M.; Madsen, Kristin K.; Marsh, Andrew J.; hide

    2016-01-01

    We present results from the first campaign of dedicated solar observations undertaken by the Nuclear Spectroscopic Telescope ARray (NuSTAR) hard X-ray (HXR) telescope. Designed as an astrophysics mission, NuSTAR nonetheless has the capability of directly imaging the Sun at HXR energies (3 keV) with an increase in sensitivity of at least two magnitude compared to current non-focusing telescopes. In this paper we describe the scientific areas where NuSTAR will make major improvements on existing solar measurements. We report on the techniques used to observe the Sun with NuSTAR, their limitations and complications, and the procedures developed to optimize solar data quality derived from our experience with the initial solar observations. These first observations are briefly described, including the measurement of the Fe K-shell lines in a decaying X-class flare, HXR emission from high in the solar corona, and full-disk HXR images of the Sun.

  10. The hard X-ray continuum of Cen a observed with INTEGRAL SPI

    Energy Technology Data Exchange (ETDEWEB)

    Burke, Mark J.; Jourdain, Elisabeth; Roques, Jean-Pierre [CNRS, IRAP, 9 Avenue Colonel Roche, BP 44346, F-31028 Toulouse cedex 4 (France); Evans, Daniel A., E-mail: mburke@irap.omp.eu [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2014-05-20

    We revisit the average hard X-ray spectrum from the active galactic nucleus (AGN) of Centaurus A (Cen A) using 10 yr worth of observations with INTEGRAL SPI. This source has the highest flux observed from any AGNs in the SPI bandpass (23 keV-8 MeV). The 10 year light curve of Cen A is presented, and hardness ratios confirm that the spectral shape changes very little despite the luminosity varying by a factor of a few. Primarily, we establish the presence of a reflection component in the average spectrum by demonstrating an excess between 20 and 60 keV, from extending the spectral shape observed at low energy to the SPI regime. The excess in Chandra HETGS and INTEGRAL SPI data is well described by reflection of the dominant power-law spectrum from a neutral, optically thick atmosphere. We find that the reprocessed emission contributes 20%-25% of the 23-100 keV flux. The existence of a cutoff at tens to hundreds of kiloelectron volts remains controversial. Using simulated spectra, we demonstrate that a high energy cutoff reproduces the observed spectral properties of Cen A more readily than a simple power law. However, we also show that such a cutoff is probably underestimated when neglecting (even modest) reflection, and for Cen A would be at energies >700 keV, with a confidence of >95%. This is atypically high for thermal Comptonizing plasmas observed in AGNs, and we propose that we are in fact modeling the more gradual change in spectral shape expected of synchrotron self-Compton spectra.

  11. Forcing Cesium into Higher Oxidation States Using Useful hard x-ray Induced Chemistry under High Pressure

    Energy Technology Data Exchange (ETDEWEB)

    Sneed, D.; Pravica, M.; Kim, E.; Chen, N.; Park, C.; White, M.

    2017-10-01

    This paper discusses our attempt to synthesize higher oxidation forms of cesium fluoride by pressurizing cesium fluoride in a fluorine-rich environment created via the x-ray decomposition of potassium tetrafluoroborate. This was done in order to confirm recent theoretical predictions of higher oxidation forms of CsFn. We discuss the development of a technique to produce molecular fluorine in situ via useful hard x-ray photochemistry, and the attempt to utilize this technique to form higher oxidation states of cesium fluoride. In order to verify the formation of the novel stoichiometric species of CsFn. X-ray Absorption Near Edge Spectroscopy (XANES) centered on the cesium K-edge was performed to probe the oxidation state of cesium as well as the local molecular coordination around Cs.

  12. Three-dimensional visualization of magnetic domain structure with strong uniaxial anisotropy via scanning hard X-ray microtomography

    Science.gov (United States)

    Suzuki, Motohiro; Kim, Kab-Jin; Kim, Sanghoon; Yoshikawa, Hiroki; Tono, Takayuki; Yamada, Kihiro T.; Taniguchi, Takuya; Mizuno, Hayato; Oda, Kent; Ishibashi, Mio; Hirata, Yuushou; Li, Tian; Tsukamoto, Arata; Chiba, Daichi; Ono, Teruo

    2018-03-01

    An X-ray tomographic technique was developed to investigate the internal magnetic domain structure in a micrometer-sized ferromagnetic sample. The technique is based on a scanning hard X-ray nanoprobe using X-ray magnetic circular dichroism (XMCD). From transmission XMCD images at the Gd L3 edge as a function of the sample rotation angle, the three-dimensional (3D) distribution of a single component of the magnetic vector in a GdFeCo microdisc was reconstructed with a spatial resolution of 360 nm, using a modified algebraic reconstruction algorithm. The method is applicable to practical magnetic materials and can be extended to 3D visualization of the magnetic domain formation process under external magnetic fields.

  13. Characterization of temporal coherence of hard X-ray free-electron laser pulses with single-shot interferograms

    Directory of Open Access Journals (Sweden)

    Taito Osaka

    2017-11-01

    Full Text Available Temporal coherence is one of the most fundamental characteristics of light, connecting to spectral information through the Fourier transform relationship between time and frequency. Interferometers with a variable path-length difference (PLD between the two branches have widely been employed to characterize temporal coherence properties for broad spectral regimes. Hard X-ray interferometers reported previously, however, have strict limitations in their operational photon energies, due to the specific optical layouts utilized to satisfy the stringent requirement for extreme stability of the PLD at sub-ångström scales. The work presented here characterizes the temporal coherence of hard X-ray free-electron laser (XFEL pulses by capturing single-shot interferograms. Since the stability requirement is drastically relieved with this approach, it was possible to build a versatile hard X-ray interferometer composed of six separate optical elements to cover a wide photon energy range from 6.5 to 11.5 keV while providing a large variable delay time of up to 47 ps at 10 keV. A high visibility of up to 0.55 was observed at a photon energy of 10 keV. The visibility measurement as a function of time delay reveals a mean coherence time of 5.9 ± 0.7 fs, which agrees with that expected from the single-shot spectral information. This is the first result of characterizing the temporal coherence of XFEL pulses in the hard X-ray regime and is an important milestone towards ultra-high energy resolutions at micro-electronvolt levels in time-domain X-ray spectroscopy, which will open up new opportunities for revealing dynamic properties in diverse systems on timescales from femtoseconds to nanoseconds, associated with fluctuations from ångström to nanometre spatial scales.

  14. High-resolution x-ray characterization of mosaic crystals for hard x-and gamma-ray astronomy

    Science.gov (United States)

    Ferrari, Claudio; Buffagni, Elisa; Marchini, Laura; Zappettini, Andrea

    2011-09-01

    We have analyzed GaAs, Cu, CdTe, and CdZnTe crystals as possible optical elements for hard x-ray lenses for x-ray astronomy. We used high resolution x-ray diffraction at 8keV in Bragg geometry and Laue transmission diffraction at synchrotron at energies up to 500 keV. A good agreement was found between the mosaicity evaluated in Bragg diffraction geometry with x-ray penetration of the order of few tens micrometers and in Laue transmission geometry at synchrotron. All the analyzed crystals showed mosaicity values in a range between a few to 150 arcseconds and suitable for the application. Nevertheless -CdTe and CdZnTe crystals exhibit non-uniformity due to the presence of low angle grain boundaries; -Cu crystals exhibit mosaicity of the order of several arcminutes; they indeed suffer by a severe cutting damage that had to be removed with a very deep etching. The FWHM was also rapidly decreasing with the x-ray energy showing that the mosaic spread is not the only origin of peak broadening; -GaAs crystals grown by Czochralski method show mosaicity up to 30 arcseconds and good diffraction efficiency up to energies of 500 keV. The use of thermal treatments as a possible method to increase the mosaic spread is also evaluated.

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

    Science.gov (United States)

    Camattari, Riccardo

    2017-09-01

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

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

    Science.gov (United States)

    Camattari, Riccardo

    2017-08-21

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

  17. Hard X-ray activity of IGR J17473-2721

    NARCIS (Netherlands)

    Kuulkers, E.; Shaw, S.; Beckmann, V.; Brandt, S.; Chenevez, J.; Courvoisier, T.J.L.; Domingo, A.; Ebisawa, K.; Jonker, P.; Kretschmar, P.; Markwardt, C.; Oosterbroek, T.; Paizis, A.; Risquez, D.; Sanchez-Fernandez, C.; Wijnands, R.

    2008-01-01

    Persistent X-ray activity has been reported by Swift/XRT (ATel #1459) and RXTE/PCA (ATel #1460) from the transient IGR J17473-2721 (= XTE J1747-274; ATels #467, #498) after the detection of an X-ray burst by SuperAGILE (ATel #1445). We report the detection of persistent activity at 18-100 keV with

  18. Hard X-ray activity of IGR J17473-2721

    DEFF Research Database (Denmark)

    Kuulkers, E.; Shaw, S.; Beckmann, V.

    2008-01-01

    Persistent X-ray activity has been reported by Swift/XRT (ATel #1459) and RXTE/PCA (ATel #1460) from the transient IGR J17473-2721 (= XTE J1747-274; ATels #467, #498) after the detection of an X-ray burst by SuperAGILE (ATel #1445). We report the detection of persistent activity at 18-100 keV wit...

  19. Hard X-Ray Flare Source Sizes Measured with the Ramaty High Energy Solar Spectroscopic Imager

    Science.gov (United States)

    Dennis, Brian R.; Pernak, Rick L.

    2009-01-01

    Ramaty High Energy Solar Spectroscopic Imager (RHESSI) observations of 18 double hard X-ray sources seen at energies above 25 keV are analyzed to determine the spatial extent of the most compact structures evident in each case. The following four image reconstruction algorithms were used: Clean, Pixon, and two routines using visibilities maximum entropy and forward fit (VFF). All have been adapted for this study to optimize their ability to provide reliable estimates of the sizes of the more compact sources. The source fluxes, sizes, and morphologies obtained with each method are cross-correlated and the similarities and disagreements are discussed. The full width at half-maximum (FWHM) of the major axes of the sources with assumed elliptical Gaussian shapes are generally well correlated between the four image reconstruction routines and vary between the RHESSI resolution limit of approximately 2" up to approximately 20" with most below 10". The FWHM of the minor axes are generally at or just above the RHESSI limit and hence should be considered as unresolved in most cases. The orientation angles of the elliptical sources are also well correlated. These results suggest that the elongated sources are generally aligned along a flare ribbon with the minor axis perpendicular to the ribbon. This is verified for the one flare in our list with coincident Transition Region and Coronal Explorer (TRACE) images. There is evidence for significant extra flux in many of the flares in addition to the two identified compact sources, thus rendering the VFF assumption of just two Gaussians inadequate. A more realistic approximation in many cases would be of two line sources with unresolved widths. Recommendations are given for optimizing the RHESSI imaging reconstruction process to ensure that the finest possible details of the source morphology become evident and that reliable estimates can be made of the source dimensions.

  20. X-Ray Absorption with Transmission X-Ray Microscopes

    NARCIS (Netherlands)

    de Groot, F.M.F.|info:eu-repo/dai/nl/08747610X

    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

  1. NuSTAR and XMM-Newton Observations of the Hard X- Ray Spectrum of Centaurus A

    Science.gov (United States)

    Furst, F.; Muller, C.; Madsen, K. K.; Lanz, L.; Rivers, E.; Brightman, M.; Arevalo, P.; Balokovic, M.; Beuchert, T.; Zhang, W.

    2016-01-01

    We present simultaneous XMM-Newton and Nuclear Spectroscopic Telescope Array (NuSTAR) observations spanning 3-78 keV of the nearest radio galaxy, Centaurus A (Cen A). The accretion geometry around the central engine in Cen A is still debated, and we investigate possible configurations using detailed X-ray spectral modeling. NuSTAR imaged the central region of Cen A with subarcminute resolution at X-ray energies above 10 keV for the first time, but found no evidence for an extended source or other off-nuclear point sources. The XMM-Newton and NuSTAR spectra agree well and can be described with an absorbed power law with a photon index Gamma = 1.8150 +/- 0.005 and a fluorescent Fe Kaline in good agreement with literature values. The spectrum is greater than 1 MeV. A thermal Comptonization continuum describes the data well, with parameters that agree with values measured by INTEGRAL, in particular an electron temperature kTe between approximately 100-300 keV and seed photon input temperatures between 5 and 50 eV. We do not find evidence for reflection or a broad iron line and put stringent upper limits of R is less than 0.01 on the reflection fraction and accretion disk illumination. We use archival Chandra data to estimate the contribution from diffuse emission, extra-nuclear point sources, and the outer X-ray jet to the observed NuSTAR and XMM-Newton X-ray spectra and find the contribution to be negligible. We discuss different scenarios for the physical origin of the observed hard X-ray spectrum and conclude that the inner disk is replaced by an advection-dominated accretion flow or that the X-rays are dominated by synchrotron self-Compton emission from the inner regions of the radio jet or a combination thereof.

  2. Characterizations of MCP performance in the hard x-ray range (6-25 keV).

    Science.gov (United States)

    Wu, Ming; Moy, Ken; Kruschwitz, Craig; Rochau, Greg

    2014-11-01

    MCP detector performance at hard x-ray energies from 6 to 25 keV was recently investigated using NSLS beamline X15A at BNL. Measurements were made with an NSTec Gen-II (H-CA-65) framing camera, based on a Photonis MCP with ∼10 μm in diameter pores, ∼12 μm center-center spacing, an L/D ratio of 46, and a bias angle of 8°. The MCP characterizations were focused on (1) energy and angle dependent sensitivity, (2) energy and angle dependent spatial resolution, (3) energy dependent gain performance, and (4) energy dependent dynamic range. These measurement corroborated simulation results using a Monte Carlo model that included hard x-ray interactions and the subsequent electron cascade in the MCP.

  3. Design and development of position sensitive detector for hard x-ray using SiPM and new generation scintillators

    Science.gov (United States)

    Goyal, S. K.; Naik, Amisha P.; N. P. S., Mithun; Vadawale, S. V.; Tiwari, Neeraj K.; Chattopadhyay, T.; Nagrani, N.; Madhavi, S.; Ladiya, T.; Patel, A. R.; Shanmugam, M.; Adalja, H. L.; Patel, V. R.; Ubale, G. P.

    2017-08-01

    There is growing interest in high-energy astrophysics community for the development of sensitive instruments in the hard X-ray energy extending to few hundred keV. This requires position sensitive detector modules with high efficiency in the hard X-ray energy range. Here, we present development of a detector module, which consists of 25 mm x 25 mm CeBr3 scintillation detector, read out by a custom designed two dimensional array of Silicon Photo-Multipliers (SiPM). Readout of common cathode of SiPMs provides the spectral measurement whereas the readout of individual SiPM anodes provides measurement of interaction position in the crystal. Preliminary results for spectral and position measurements with the detector module are presented here.

  4. Penetrating view of nano-structures in Aleochara verna spermatheca and flagellum by hard X-ray microscopy

    Science.gov (United States)

    Zhang, Kai; Li, De-E.; Hong, You-Li; Zhu, Pei-Ping; Yuan, Qing-Xi; Huang, Wan-Xia; Gao, Kun; Zhou, Hong-Zhang; Wu, Zi-Yu

    2013-07-01

    A penetrating view of the three-dimensional nanostructure of female spermatheca and male flagellum in the species Aleochara verna is obtained with 100-nm resolution using a hard X-ray microscope, which provides a fast noninvasive imaging technology for insect morphology. Through introducing Zernike phase contrast and heavy metal staining, images taken at 8 keV displayed sufficient contrast for observing nanoscale fine structures, such as the spermatheca cochleate duct and the subapex of the flagellum, which have some implications for the study of the sperm transfer process and genital evolution in insects. This work shows that both the spatial resolution and the contrast characteristic of hard X-ray microscopy are quite promising for insect morphology studies and, particularly, provide an attractive alternative to the destructive techniques used for investigating internal soft tissues.

  5. Mechanical design of multiple zone plates precision alignment apparatus for hard X-ray focusing in twenty-nanometer scale

    Science.gov (United States)

    Shu, Deming; Liu, Jie; Gleber, Sophie C.; Vila-Comamala, Joan; Lai, Barry; Maser, Jorg M.; Roehrig, Christian; Wojcik, Michael J.; Vogt, Franz Stefan

    2017-04-04

    An enhanced mechanical design of multiple zone plates precision alignment apparatus for hard x-ray focusing in a twenty-nanometer scale is provided. The precision alignment apparatus includes a zone plate alignment base frame; a plurality of zone plates; and a plurality of zone plate holders, each said zone plate holder for mounting and aligning a respective zone plate for hard x-ray focusing. At least one respective positioning stage drives and positions each respective zone plate holder. Each respective positioning stage is mounted on the zone plate alignment base frame. A respective linkage component connects each respective positioning stage and the respective zone plate holder. The zone plate alignment base frame, each zone plate holder and each linkage component is formed of a selected material for providing thermal expansion stability and positioning stability for the precision alignment apparatus.

  6. New hard X-ray sources discovered in the ongoing INTEGRAL Galactic plane survey after 14 yr of observations

    Science.gov (United States)

    Krivonos, Roman A.; Tsygankov, Sergey S.; Mereminskiy, Ilya A.; Lutovinov, Alexander A.; Sazonov, Sergey Yu.; Sunyaev, Rashid A.

    2017-09-01

    The International Gamma-Ray Astrophysics Laboratory (INTEGRAL) continues to successfully work in orbit after its launch in 2002. The mission provides the deepest ever survey of hard X-ray sources throughout the Galaxy at energies above 20 keV. We report on a catalogue of new hard X-ray source candidates based on the latest sky maps comprising 14 yr of data acquired with the IBIS telescope onboard INTEGRAL in the Galactic Plane (|b| 4.7σ and not known to previous INTEGRAL surveys. Among them, 31 objects have also been detected in the on-going all-sky survey by the BAT telescope of the Swift observatory. For 26 sources on the list, we suggest possible identifications: 21 active galactic nuclei, two cataclysmic variables, two isolated pulsars or pulsar wind nebulae and one supernova remnant; 46 sources from the catalogue remain unclassified.

  7. Small d-spacing WC/SiC multilayers for future hard X-ray telescope designs

    DEFF Research Database (Denmark)

    Jensen, C.P.; Madsen, K.K.; Christensen, Finn Erland

    2005-01-01

    Multilayer coatings for reflecting hard X-rays up to 80keV, like W/Si and Pt/C, have been studied for several years. To go to higher energies, in the range of 100 keV to 250 keV, one needs coatings with smaller d-spacings than can currently be made with these material combinations, and a lower...... with reasonable focal lengths and throughput up to 250 keV....

  8. From Storage Rings to Free Electron Lasers for Hard X-Rays

    Energy Technology Data Exchange (ETDEWEB)

    Nuhn, H

    2004-01-09

    The intensity of X-ray sources has increased at a rapid rate since the late 1960s by 10 orders of magnitude and more through the use of synchrotron radiation produced by bending magnets, wigglers and undulators. Three generations of radiation sources have been identified depending on amplitude and quality of the radiation provided. While user facilities of the third generation were being constructed a new concept of radiation generating devices was being developed that offers an even larger increase in peak and average brightness than had been achieved till then. The new concept of the X-ray Free Electron Laser based on the principle of Self-Amplified Spontaneous Emission will be the basis of fourth generation X-ray source user facilities of this century. The paper will start with a brief history of the development of x-ray sources, discuss some of the differences between storage ring and free electron laser based approaches, and close with an update of the present development of x-ray free electron laser user facilities.

  9. A hard X-ray study of the ultraluminous X-ray source NGC 5204 X-1 with NuSTAR and XMM-Newton

    DEFF Research Database (Denmark)

    Mukherjee, E. S.; Walton, D. J.; Bachetti, M.

    2015-01-01

    We present the results from coordinated X-ray observations of the ultraluminous X-ray source NGC 5204 X-1 performed by the Nuclear Spectroscopic Telescope Array and XMM-Newton in early 2013. These observations provide the first detection of NGC 5204 X-1 above 10 keV, extending the broadband...

  10. The Hard X-Ray Spectrum as a Probe for Black Hole Growth in Radio-Quiet Active Galactic Nuclei

    Science.gov (United States)

    Shemmer, Ohad; Brandt, W. N.; Netzer, Hagai; Maiolino, Roberto; Kaspi, Shai

    2008-07-01

    We study the hard X-ray spectral properties of 10 highly luminous radio-quiet (RQ) active galactic nuclei (AGNs) at z = 1.3-3.2, including new XMM-Newton observations of four of these sources. We find a significant correlation between the normalized accretion rate (L/LEdd) and the hard X-ray photon index (Γ) for 35 moderate- to high-luminosity RQ AGNs, including our 10 highly luminous sources. Within the limits of our sample, we show that a measurement of Γ and LX can provide an estimate of L/LEdd and black hole mass (MBH) with a mean uncertainty of a factor of lesssim3 on the predicted values of these properties. This may provide a useful probe for tracing the history of BH growth in the universe, utilizing samples of X-ray-selected AGNs for which L/LEdd and MBH have not yet been determined systematically. It may prove to be a useful way to probe BH growth in distant Compton-thin type 2 AGNs. We also find that the optical-X-ray spectral slope (αox) depends primarily on optical-UV luminosity rather than on L/LEdd in a sample of RQ AGNs spanning 5 orders of magnitude in luminosity and over 2 orders of magnitude in L/LEdd. We detect a significant Compton-reflection continuum in two of our highly luminous sources, and in the stacked X-ray spectrum of seven other sources with similar luminosities, we obtain a mean relative Compton reflection of R = 0.9+ 0.6-0.5 and an upper limit on the rest-frame equivalent width of a neutral Fe Kα line of 105 eV. We do not detect a significant steepening of the X-ray power-law spectrum below rest-frame 2 keV in any of our highly luminous sources, suggesting that a soft-excess feature, commonly observed in local AGNs, either does not depend strongly on L/LEdd, or is not accessible at high redshifts using current X-ray detectors.

  11. Experimental Evaluation And Simulation Of Multi-pixel Cadmium-zinc-telluride Hard-x-ray Detectors

    CERN Document Server

    Gaskin, J A

    2004-01-01

    This dissertation describes the evaluation of many-pixel Cadmium-Zinc-Telluride (CdZnTe) hard-X-ray detectors for future use with the High Energy Replicated Optics (HERO) telescope being developed at Marshall Space Flight Center. The detector requirements for the HERO application are good energy resolution (sufficient to resolve cyclotron features and nuclear lines), spatial resolution of ∼200 μm, minimal charge loss of absorbed X rays, and minimal sensitivity to the background environment. This research concentrates on assessing the suitability of these detectors for the focus of HERO, and includes the development of a simulation of the physics involved in an X-ray-detector interaction, a study of the intrinsic material properties, measurements with prototype detectors such as the energy and spatial resolution, charge loss, and X-ray background reduction through 3-dimensional depth sensing. Two types of detectors were available for evaluation. The first type includes 1-mm and 2-mm thick 4 x 4 ...

  12. A hard x-ray split-and-delay unit for the HED instrument at the European XFEL

    Science.gov (United States)

    Roling, Sebastian; Kärcher, Victor; Samoylova, Liubov; Appel, Karen; Braun, Stefan; Gawlitza, Peter; Siewert, Frank; Zastrau, Ulf; Rollnik, Matthias; Wahlert, Frank; Zacharias, Helmut

    2017-06-01

    For the High Energy Density Instrument (HED) at the European XFEL a hard x-ray split-and-delay unit (SDU) is built covering photon energies in the range between 5 keV and 24 keV. This SDU enables time-resolved x-ray pump / x-ray probe experiments as well as sequential diffractive imaging on a femtosecond to picosecond time scale. The set-up is based on wavefront splitting that has successfully been implemented at an autocorrelator at FLASH. The x-ray FEL pulses will be split by a sharp edge of a silicon mirror coated with Mo/B4C and W/B4C multilayers. Both partial beams then pass variable delay lines. For different photon energies the angle of incidence onto the multilayer mirrors is adjusted in order to match the Bragg condition. Hence, maximum delays between +/- 1 ps at 24 keV and up to +/- 23 ps at 5 keV will be possible. Time-dependent wave-optics simulations are performed with Synchrotron Radiation Workshop (SRW) software. The XFEL radiation is simulated using the output of the time-dependent SASE code FAST. For the simulations diffraction on the edge of the beam-splitter as well as height and slope errors of all eight mirror surfaces are taken into account. The impact of these effects on the ability to focus the beam by means of compound refractive lenses (CRL) is analyzed.

  13. 11 nm hard X-ray focus from a large-aperture multilayer Laue lens.

    Science.gov (United States)

    Huang, Xiaojing; Yan, Hanfei; Nazaretski, Evgeny; Conley, Raymond; Bouet, Nathalie; Zhou, Juan; Lauer, Kenneth; Li, Li; Eom, Daejin; Legnini, Daniel; Harder, Ross; Robinson, Ian K; Chu, Yong S

    2013-12-20

    The focusing performance of a multilayer Laue lens (MLL) with 43.4 μm aperture, 4 nm finest zone width and 4.2 mm focal length at 12 keV was characterized with X-rays using ptychography method. The reconstructed probe shows a full-width-at-half-maximum (FWHM) peak size of 11.2 nm. The obtained X-ray wavefront shows excellent agreement with the dynamical calculations, exhibiting aberrations less than 0.3 wave period, which ensures the MLL capable of producing a diffraction-limited focus while offering a sufficient working distance. This achievement opens up opportunities of incorporating a variety of in-situ experiments into ultra high-resolution X-ray microscopy studies.

  14. High-resolution interference-monochromator for hard X-rays.

    Science.gov (United States)

    Tsai, Yi-Wei; Chang, Ying-Yi; Wu, Yu-Hsin; Lee, Kun-Yuan; Liu, Shih-Lun; Chang, Shih-Lin

    2016-12-26

    An X-ray interference-monochromator combining a Fabry-Perot resonator (FPR) and a double-crystal monochromator (DCM) is proposed and realized for obtaining single-mode X-rays with 3.45 meV energy resolution. The monochromator is based on the generation of cavity interference fringes from a FPR and single-mode selection of the transmission spectrum by a DCM of a nearly backward symmetric reflection geometry. The energy of the monochromator can be tuned within 2500 meV(= ΔE) by temperature control of the FPR and the DCM crystals in the range of ΔT = 70 K at room temperature. The diffraction geometry and small size of the optical components used make the interference-monochromator very easy to be adapted in modern synchrotron beamlines and X-ray optics applications.

  15. Generation of stable subfemtosecond hard x-ray pulses with optimized nonlinear bunch compression

    Directory of Open Access Journals (Sweden)

    Senlin Huang

    2014-12-01

    Full Text Available In this paper, we propose a simple scheme that leverages existing x-ray free-electron laser hardware to produce stable single-spike, subfemtosecond x-ray pulses. By optimizing a high-harmonic radio-frequency linearizer to achieve nonlinear compression of a low-charge (20 pC electron beam, we obtain a sharp current profile possessing a few-femtosecond full width at half maximum temporal duration. A reverse undulator taper is applied to enable lasing only within the current spike, where longitudinal space charge forces induce an electron beam time-energy chirp. Simulations based on the Linac Coherent Light Source parameters show that stable single-spike x-ray pulses with a duration less than 200 attoseconds can be obtained.

  16. Multiwavelength observations of Active Galactic Nuclei from the radio to the hard X-rays

    Science.gov (United States)

    Beuchert, Tobias

    2017-07-01

    Active Galaxies form a peculiar type of galaxies. Their cores, the so-called "Active Galactic Nuclei" (AGN), are the most persistent luminous objects in the universe. Accretion of several solar masses per year onto black holes of Millions to Billions of solar masses drive the immense energy output of these systems, which can exceed that of the entire galaxy. The compact energy source, however, only measures about one over a Billion times that of the entire galaxy. Subject of my thesis are observations of the two main channels of energy release of selected AGN systems, both of which are encompassed by profound and yet unanswered questions. These channels are on the one hand the pronounced X-ray emission of the hot and compact accreting environment in close vicinity of the black hole, and on the other hand the radio synchrotron emission of magnetically collimated jets that are fed by portions of the accreted matter. These jets also function as effective accelerators and drive the injected matter deep into the intergalactic medium. As the circumnuclear environment of AGN is too compact to be spatially resolved in the X-rays, I show how X-ray spectroscopy can be used to: (1) understand the effects of strong gravity to trace the geometry and physics of the X-ray source and (2) more consistently quantify matter that surrounds and dynamically absorbs our direct line of sight towards the X-ray source. Second, I unveil the valuable information contained in the polarized radio light being emitted from magnetized jet outflows. In contrast to the X-ray emitting region, I am able to spatially resolve the inner parts of the jet of a prominent galaxy with help of the Very Long Baseline Array, a large network of radio telescopes. The resulting polarization maps turn out to be exceptionally promising in answering fundamental questions related to jet physics.

  17. Coherent storage and phase modulation of single hard-x-ray photons using nuclear excitons.

    Science.gov (United States)

    Liao, Wen-Te; Pálffy, Adriana; Keitel, Christoph H

    2012-11-09

    The coherent storage and phase modulation of x-ray single-photon wave packets in the resonant scattering of light off nuclei is theoretically investigated. We show that by switching off and on again the magnetic field in the nuclear sample, phase-sensitive storage of photons in the keV regime can be achieved. Corresponding π phase modulation of the stored photon can be accomplished if the retrieving magnetic field is rotated by 180°. The development of such x-ray single-photon control techniques is a first step towards forwarding quantum optics and quantum information to shorter wavelengths and more compact photonic devices.

  18. Generation of hard x rays by femtosecond laser pulse interaction with solid targets in atmosphere.

    Science.gov (United States)

    Zhidkov, Alexey G; Pikuz, Sergey A; Faenov, Anatoly Ya; Chefonov, Oleg V; Ovchinnikov, Andrey V; Agranat, Mikhail B; Zigler, Arie

    2012-03-01

    X ray radiation as high as 50 keV, including K(α) of Ba and Mo, have been observed from a solid target during the interaction of low energy ~0.65 mJ, 1 kHz 40 femtosecond laser pulses focused in air at atmospheric pressure. Energetic electrons generating such x rays are possibly produced when the field strength in laser pulse wake exceeds the runaway threshold in air. Two dimensional particle-in-cell simulations that include optical field ionization of air and elastic collisions support this mechanism. © 2012 Optical Society of America

  19. Extended Hard-X-Ray Emission in the Inner Few Parsecs of the Galaxy

    Science.gov (United States)

    Perez, Kerstin; Hailey, Charles J.; Bauer, Franz E.; Krivonos, Roman A.; Mori, Kaya; Baganoff, Frederick K.; Barriere, Nicholas M.; Boggs, Steven E.; Christensen, Finn E.; Craig, William W.; hide

    2015-01-01

    The Galactic Centre hosts a puzzling stellar population in its inner few parsecs, with a high abundance of surprisingly young, relatively massive stars bound within the deep potential well of the central supermassive black hole, Sagittarius A* (ref. 1). Previous studies suggest that the population of objects emitting soft X-rays (less than 10 kiloelectronvolts) within the surrounding hundreds of parsecs, as well as the population responsible for unresolved X-ray emission extending along the Galactic plane, is dominated by accreting white dwarf systems2, 3, 4, 5.

  20. Coherent hard x-rays from attosecond pulse train-assisted harmonic generation

    OpenAIRE

    Klaiber, Michael; Hatsagortsyan, Karen Z.; Müller, Carsten; Keitel, Christoph H.

    2007-01-01

    High-order harmonic generation from atomic systems is considered in the crossed fields of a relativistically strong infrared laser and a weak attosecond-pulse train of soft x-rays. Due to one-photon ionization by the x-ray pulse, the ionized electron obtains a starting momentum that compensates the relativistic drift which is induced by the laser magnetic field, and allows the electron to efficiently emit harmonic radiation upon recombination with the atomic core in the relativistic regime. I...

  1. CdZnTe Image Detectors for Hard-X-Ray Telescopes

    Science.gov (United States)

    Chen, C. M. Hubert; Cook, Walter R.; Harrison, Fiona A.; Lin, Jiao Y. Y.; Mao, Peter H.; Schindler, Stephen M.

    2005-01-01

    Arrays of CdZnTe photodetectors and associated electronic circuitry have been built and tested in a continuing effort to develop focal-plane image sensor systems for hard-x-ray telescopes. Each array contains 24 by 44 pixels at a pitch of 498 m. The detector designs are optimized to obtain low power demand with high spectral resolution in the photon- energy range of 5 to 100 keV. More precisely, each detector array is a hybrid of a CdZnTe photodetector array and an application-specific integrated circuit (ASIC) containing an array of amplifiers in the same pixel pattern as that of the detectors. The array is fabricated on a single crystal of CdZnTe having dimensions of 23.6 by 12.9 by 2 mm. The detector-array cathode is a monolithic platinum contact. On the anode plane, the contact metal is patterned into the aforementioned pixel array, surrounded by a guard ring that is 1 mm wide on three sides and is 0.1 mm wide on the fourth side so that two such detector arrays can be placed side-by-side to form a roughly square sensor area with minimal dead area between them. Figure 1 shows two anode patterns. One pattern features larger pixel anode contacts, with a 30-m gap between them. The other pattern features smaller pixel anode contacts plus a contact for a shaping electrode in the form of a grid that separates all the pixels. In operation, the grid is held at a potential intermediate between the cathode and anode potentials to steer electric charges toward the anode in order to reduce the loss of charges in the inter-anode gaps. The CdZnTe photodetector array is mechanically and electrically connected to the ASIC (see Figure 2), either by use of indium bump bonds or by use of conductive epoxy bumps on the CdZnTe array joined to gold bumps on the ASIC. Hence, the output of each pixel detector is fed to its own amplifier chain.

  2. Hard X-ray polarimetry with Caliste, a high performance CdTe based imaging spectrometer

    Science.gov (United States)

    Antier, S.; Ferrando, P.; Limousin, O.; Caroli, E.; Curado da Silva, R. M.; Blondel, C.; Chipaux, R.; Honkimaki, V.; Horeau, B.; Laurent, P.; Maia, J. M.; Meuris, A.; Del Sordo, S.; Stephen, J. B.

    2015-06-01

    Since the initial exploration of the X- and soft γ-ray sky in the 60's, high-energy celestial sources have been mainly characterized through imaging, spectroscopy and timing analysis. Despite tremendous progress in the field, the radiation mechanisms at work in sources such as neutrons stars, black holes, and Active Galactic Nuclei are still unclear. The polarization state of the radiation is an observational parameter which brings key additional information about the physical processes in these high energy sources, allowing the discrimination between competing models which may otherwise all be consistent with other types of measurement. This is why most of the projects for the next generation of space missions covering the few tens of keV to the MeV region require a polarization measurement capability. A key element enabling this capability, in this energy range, is a detector system allowing the identification and characterization of Compton interactions as they are the main process at play. The compact hard X-ray imaging spectrometer module, developed in CEA with the generic name of "Caliste" module, is such a detector. In this paper, we present experimental results for two types of Caliste-256 modules, one based on a CdTe crystal, the other one on a CdZnTe crystal, which have been exposed to linearly polarized beams at the European Synchrotron Radiation Facility (ESRF). These results, obtained at 200 and 300 keV, demonstrate the capability of these modules to detect Compton events and to give an accurate determination of the polarization parameters (polarization angle and fraction) of the incoming beam. For example, applying an optimized selection to our data set, equivalent to select 90° Compton scattered interactions in the detector plane, we find a modulation factor Q of 0.78 ± 0.06 in the 200-300 keV range. The polarization angle and fraction are derived with accuracies of approximately 1° and 5 % respectively for both CdZnTe and CdTe crystals. The

  3. Design of MiSolFA Hard X-Ray Imager

    Science.gov (United States)

    Lastufka, Erica; Casadei, Diego

    2017-08-01

    Advances in the study of coronal electron-accelerating regions have so far been limited by the dynamic range of X-ray instruments. A quick and economical alternative to desirable focusing optics technology is stereo observation. The micro-satellite MiSolFA (Micro Solar-Flare Apparatus) is designed both as a stand-alone X-ray imaging spectrometer and a complement to the Spectrometer/Telescope for Imaging X-rays (STIX) mission. These instruments will be the first pair of cross-calibrated X-ray imaging spectrometers to look at solar flares from very different points of view. MiSolFA will achieve indirect imaging between 10 and 60 keV and provide spectroscopy up to 100 keV, equipped with grids producing moiré patterns in a similar way to STIX. New manufacturing techniques produce gold gratings on a graphite or silicon substrate, with periods ranging from 15 to 225 micrometers, separated by a distance of 15.47 cm, to achieve a spatial resolutions from 10" to 60" (as compared to RHESSI's separation of 150 cm and 1" resolution). We present the progress of the imager design, the performance of the first prototypes, and reach out to the community for further scientific objectives to consider in optimizing the final design.

  4. Trends in hard X-ray fluorescence mapping: environmental applications in the age of fast detectors

    Energy Technology Data Exchange (ETDEWEB)

    Lombi, E.; Donner, E. [University of South Australia, Centre for Environmental Risk Assessment and Remediation, Mawson Lakes, South Australia (Australia); CRC CARE, PO Box 486, Salisbury, South Australia (Australia); Jonge, M.D. de; Paterson, D. [Australian Synchrotron, X-ray Fluorescence Microscopy, 800 Blackburn Road, Clayton, Victoria (Australia); Ryan, C.G. [CSIRO Earth Science and Resource Engineering, Normanby Road, Clayton, Victoria (Australia)

    2011-06-15

    Environmental samples are extremely diverse but share a tendency for heterogeneity and complexity. This heterogeneity poses methodological challenges when investigating biogeochemical processes. In recent years, the development of analytical tools capable of probing element distribution and speciation at the microscale have allowed this challenge to be addressed. Of these available tools, laterally resolved synchrotron techniques such as X-ray fluorescence mapping are key methods for the in situ investigation of micronutrients and inorganic contaminants in environmental samples. This article demonstrates how recent advances in X-ray fluorescence detector technology are bringing new possibilities to environmental research. Fast detectors are helping to circumvent major issues such as X-ray beam damage of hydrated samples, as dwell times during scanning are reduced. They are also helping to reduce temporal beamtime requirements, making particularly time-consuming techniques such as micro X-ray fluorescence ({mu}XRF) tomography increasingly feasible. This article focuses on {mu}XRF mapping of nutrients and metalloids in environmental samples, and suggests that the current divide between mapping and speciation techniques will be increasingly blurred by the development of combined approaches. (orig.)

  5. Surface roughness-aided hard X-ray emission from carbon nanotubes

    Indian Academy of Sciences (India)

    MWNT) irradiated by intense, femtosecond laser over an intensity range of 1015 –1017 W cm−2 2 is reported. The MWNT targets yield two orders of magnitude higher X-rays (indicating significant enhancement of laser coupling) and three ...

  6. Research on pinches driven by Speed-2 generator: Hard X-ray and neutron emission in plasma focus configuration

    Energy Technology Data Exchange (ETDEWEB)

    Soto, L.; Moreno, J.; Silva, P.; Sylvester, G.; Zambra, M.; Pavez, C. [Comision Chilena de Energia Nuclear, Santiago (Chile); Pavez, C. [Universidad de Concepcion (Chile); Raspa, V. [Buenos Aires Univ., PLADEMA, CONICET and INFIP (Argentina); Castillo, F. [Insitituto de Ciencias Nucleares, UNAM (Mexico); Kies, W. [Heinrich-Heine-Univ., Dusseldorf (Germany)

    2004-07-01

    Speed-2 is a generator based on Marx technology and was designed in the University of Dusseldorf. Speed-2 consists on 40 +/- Marx modules connected in parallel (4.1 {mu}F equivalent Marx generator capacity, 300 kV, 4 MA in short circuit, 187 kJ, 400 ns rise time, dI/dt {approx} 10{sup 13} A/s). Currently Speed-2 is operating at CCHEN (Chilean nuclear energy commission), being the most powerful and energetic device for dense transient plasma in the Southern Hemisphere. Most of the previous works developed in Speed-2 at Dusseldorf were done in a plasma focus configuration for soft X-ray emission and the neutron emission from Speed-2 was not completely studied. The research program at CCHEN considers experiments in different pinch configurations (plasma focus, gas puffed plasma focus, gas embedded Z-pinch, wire arrays) at current of hundred of kilo- to mega-amperes, using the Speed-2 generator. The Chilean operation has begun implementing and developing diagnostics in a conventional plasma focus configuration operating in deuterium in order to characterize the neutron emission and the hard X-ray production. Silver activation counters, plastics CR39 and scintillator-photomultiplier detectors are used to characterize the neutron emission. Images of metallic plates with different thickness are obtained on commercial radiographic film, Agfa Curix ST-G2, in order to characterize an effective energy of the hard X-ray outside of the discharge. (authors)

  7. Su Lyncis, a Hard X-Ray Bright M Giant: Clues Point to a Large Hidden Population of Symbiotic Stars

    Science.gov (United States)

    Mukai, K.; Luna, G. J. M.; Cusumano, G.; Segreto, A.; Munari, U.; Sokoloski, J. L.; Lucy, A. B.; Nelson, T.; Nunez, N. E.

    2016-01-01

    Symbiotic star surveys have traditionally relied almost exclusively on low resolution optical spectroscopy. However, we can obtain a more reliable estimate of their total Galactic population by using all available signatures of the symbiotic phenomenon. Here we report the discovery of a hard X-ray source, 4PBC J0642.9+5528, in the Swift hard X-ray all-sky survey, and identify it with a poorly studied red giant, SU Lyn, using pointed Swift observations and ground-based optical spectroscopy. The X-ray spectrum, the optical to UV spectrum, and the rapid UV variability of SU Lyn are all consistent with our interpretation that it is a symbiotic star containing an accreting white dwarf. The symbiotic nature of SU Lyn went unnoticed until now, because it does not exhibit emission lines strong enough to be obvious in low resolution spectra. We argue that symbiotic stars without shell-burning have weak emission lines, and that the current lists of symbiotic stars are biased in favor of shell-burning systems. We conclude that the true population of symbiotic stars has been underestimated, potentially by a large factor.

  8. Observing the Sun in hard X-rays using grazing incidence optics: the FOXSI and HEROES projects

    Science.gov (United States)

    Christe, Steven; Glesener, Lindsay; Krucker, Sam; Shih, Albert Y.; Gaskin, Jessica; Wilson, Colleen

    2014-06-01

    Solar flares accelerate particles up to high energies through various acceleration mechanisms which are not currently understood. Hard X-rays are the most direct diagnostic of flare-accelerated electrons. However past and current hard x-ray observation lack the sensitivity and dynamic range necessary to observe the faint signature of accelerated electrons in the acceleration region, the solar corona. These limitations can be easily overcome through the use of HXR focusing optics coupled with solid state pixelated detectors. We present results from the recent flights of two sub-orbital payloads that have applied grazing incidence HXR optics to solar observations. FOXSI, short for Focusing Optics X-Ray Solar Imager, was launched on a sounding rocket in November 2012 from White Sanda and observed a solar flare. HEROES, short for High Energy Replicated Optics to Explore the Sun, observed the sun for 7 hours from a high altitude balloon on September 21, 2013. We present recent results as well as the capabilities of a possible future satellite mission

  9. Lifting the Veil on Supermassive Black Holes: AGN Science With The EXIST Hard X-ray Satellite

    Science.gov (United States)

    Coppi, Paolo S.; Della Ceca, R.; Grindlay, J.; Ghisellini, G.; Tagliaferri, G.; Treister, E.; Papadakis, I.; EXIST Science Team

    2010-01-01

    Once considered exotic objects, accreting supermassive blackholes (AGN) and their "feedback" may in fact play a key role in the formation of the structure we see around us today. With its large collection area, simultaneous broad-band energy coverage from 0.5 to 600 keV, and all-sky monitoring capability, the proposed EXIST hard X-ray satellite mission provides an unrivaled census of transient AGN activity in the nearby( zEXIST will also find the most powerful and rare accretors out to high redshifts, z 8 in the case of blazar AGN, stressing structure formation theories and finding useful lines of sight to probe the intervening universe. We review how an EXIST hard X-ray survey, coupled with a follow-up survey using its on-board soft X-ray (SXT) and optical/near-infrared (IRT) telescopes, significantly advances our understanding of AGN physics and its role in the overall process of galaxy formation.

  10. Nanofabrication and characterization of a grating-based condenser for uniform illumination with hard X-rays.

    Science.gov (United States)

    Liu, Jianpeng; Li, Xin; Chen, Shuo; Zhang, Sichao; Xie, Shanshan; Xu, Chen; Chen, Yifang; Deng, Biao; Mao, Chenwen

    2017-05-01

    In the development of full-field transmission X-ray microscopy for basic study in science and technology, a condenser capable of providing intense illumination with high uniformity and stability on tested specimens in order to achieve high-quality images is essential. The latest design of a square-shaped condenser based on diffractive gratings has demonstrated promising uniformity in illumination. This paper describes in more detail the development of such a beam shaper for hard X-rays at 10 keV with regard to its design, manufacture and optical characterization. The effect of the grating profile on the diffracted intensity has been theoretically predicted by numerical simulation using the finite-difference time-domain method. Based on this, the limitations of the grating-based condenser are discussed.

  11. High-resolution hard x-ray spectroscopy of high-temperature plasmas using an array of quantum microcalorimeters.

    Science.gov (United States)

    Thorn, Daniel B; Gu, Ming F; Brown, Greg V; Beiersdorfer, Peter; Porter, F Scott; Kilbourne, Caroline A; Kelley, Richard L

    2008-10-01

    Quantum microcalorimeters show promise in being able to fully resolve x-ray spectra from heavy highly charged ions, such as would be found in hot plasmas with temperatures in excess of 50 keV. Quantum microcalorimeter arrays are able to achieve this as they have a high-resolving power and good effective quantum efficiency for hard x-ray photons up to 60 keV. To demonstrate this, we present a measurement using an array of thin HgTe quantum microcalorimeters to measure the K-shell spectrum of hydrogenlike through carbonlike praseodymium (Z=57). With this device we are able to attain a resolving power, E/DeltaE, of 1000 at a photon energy of 37 keV.

  12. High Resolution X-ray Characterization Of Mosaic Crystals For Hard X- And Gamma-ray Astronomy

    Science.gov (United States)

    Marchini, L.; Ferrari, C.; Buffagni, E.; Zappettini, A.

    2011-09-01

    For hard X-ray astronomy in the 70-1000 keV energy range Laue lenses have been proposed where the focusing elements are made of single mosaic crystals, in order to increase the diffraction efficiency with respect to perfect crystals. Suitable crystals to be used for such application should have a sufficient density to increase the diffraction efficiency and a mosaicity ranging between 30 arcsec and 1-2 arcmin, depending on the lens focusing distance and resolution. In the past germanium and copper crystals, often employed as monochromators for neutrons, have been considered. In this work we propose several crystalline materials of different degree of crystal perfection such as GaAs, Cu, CdTe, and CdZnTe as possible mosaic crystals for hard X-ray astronomy. They were analyzed by high resolution X-ray diffraction at 8 keV and by diffraction at energies up to 700 keV at synchrotron. It was found that: CdTe and CdZnTe crystals exhibit low angle grain boundaries preventing the formation of a single diffracted X-ray beam; Cu crystals exhibit mosaicity of the order of several arcmin, however a deep etching is needed to remove the cutting damage; GaAs crystals grown by LEC method show mosaicity between 15 and 30 arcsec and good diffraction efficiency up to energies of 700 keV. Annealing and surface damage were considered as possible methods to increase the GaAs crystal mosaicity.

  13. Experimental results on hard x-ray energy emitted by a low-energy plasma focus device: a radiographic image analysis

    Energy Technology Data Exchange (ETDEWEB)

    Zambra, Marcelo; Pavez, Cristian; Pasten, Denisse; Moreno, Jose; Soto, Leopoldo [Comision Chilena de EnergIa Nuclear, Amunategui 95, PO Box 188-D, Santiago (Chile); Silva, Patricio, E-mail: mzambra@cchen.c

    2009-12-15

    The PF-400J plasma focus device (400 J of energy) was studied in a similar way to a pulsed source of high-energy x-ray radiation. High-sensitivity fast-response commercial radiographic film and different metal filter array combinations were used to study the energy of the proper emitted x-ray. The effective energy of the hard x-ray radiation is studied and discussed in terms of its effective mean attenuation with the penetration distance on different metallic samples when the x-ray pulsed beam is supposed monoenergetic. These results were then used to assess the energetic properties of the pulsed radiation when different x-ray film-filter array combinations were irradiated between tens to almost 160 effective pulses of x-ray coming from the PF-400J device.

  14. Experimental results on hard x-ray energy emitted by a low-energy plasma focus device: a radiographic image analysis

    Science.gov (United States)

    Zambra, Marcelo; Silva, Patricio; Pavez, Cristian; Pasten, Denisse; Moreno, José; Soto, Leopoldo

    2009-12-01

    The PF-400J plasma focus device (400 J of energy) was studied in a similar way to a pulsed source of high-energy x-ray radiation. High-sensitivity fast-response commercial radiographic film and different metal filter array combinations were used to study the energy of the proper emitted x-ray. The effective energy of the hard x-ray radiation is studied and discussed in terms of its effective mean attenuation with the penetration distance on different metallic samples when the x-ray pulsed beam is supposed monoenergetic. These results were then used to assess the energetic properties of the pulsed radiation when different x-ray film-filter array combinations were irradiated between tens to almost 160 effective pulses of x-ray coming from the PF-400J device.

  15. Synchrotron hard X-ray imaging of shock-compressed metal powders

    Science.gov (United States)

    Rutherford, Michael E.; Chapman, David J.; Collinson, Mark A.; Jones, David R.; Music, Jasmina; Stafford, Samuel J. P.; Tear, Gareth R.; White, Thomas G.; Winters, John B. R.; Drakopoulos, Michael; Eakins, Daniel E.

    2015-06-01

    This poster will present the application of a new, high-energy (50 to 250 keV) synchrotron X-ray radiography technique to the study of shock-compressed granular materials. Following plate-impact loading, transmission radiography was used to quantitatively observe the compaction and release processes in a range of high-Z metal powders (e.g. Fe, Ni, Cu). By comparing the predictions of 3D numerical models initialized from X-ray tomograms-captured prior to loading-with experimental results, this research represents a new approach to refining mesoscopic compaction models. The authors gratefully acknowledge the ongoing support of Imperial College London, EPSRC, STFC and the Diamond Light Source, and AWE Plc.

  16. INTEGRAL detection of continued hard X-ray emission from MAXI J0911-655

    Science.gov (United States)

    Victor, J.-G.; Kuulkers, E.; Sidoli, L.; Sanchez-Fernandez, C.; Watanabe, K.; Pavan, L.; Bozzo, E.

    2017-05-01

    During the observations performed in the direction of the Carina Region and IGR J11014-6103 between 2017 May 8 at 04:50 and May 24 at 17:39, INTEGRAL detected activity from the accreting millisecond X-ray pulsar (AMXP) MAXI J0911-655 (Sanna et al., 2017, A & A, 598, 34; Atel #8872, #8884, #8914, #8971, #8986, #9738, #9740).

  17. Experimental strategies for imaging bioparticles with femtosecond hard X-ray pulses

    Directory of Open Access Journals (Sweden)

    Benedikt J. Daurer

    2017-05-01

    Full Text Available This study explores the capabilities of the Coherent X-ray Imaging Instrument at the Linac Coherent Light Source to image small biological samples. The weak signal from small samples puts a significant demand on the experiment. Aerosolized Omono River virus particles of ∼40 nm in diameter were injected into the submicrometre X-ray focus at a reduced pressure. Diffraction patterns were recorded on two area detectors. The statistical nature of the measurements from many individual particles provided information about the intensity profile of the X-ray beam, phase variations in the wavefront and the size distribution of the injected particles. The results point to a wider than expected size distribution (from ∼35 to ∼300 nm in diameter. This is likely to be owing to nonvolatile contaminants from larger droplets during aerosolization and droplet evaporation. The results suggest that the concentration of nonvolatile contaminants and the ratio between the volumes of the initial droplet and the sample particles is critical in such studies. The maximum beam intensity in the focus was found to be 1.9 × 1012 photons per µm2 per pulse. The full-width of the focus at half-maximum was estimated to be 500 nm (assuming 20% beamline transmission, and this width is larger than expected. Under these conditions, the diffraction signal from a sample-sized particle remained above the average background to a resolution of 4.25 nm. The results suggest that reducing the size of the initial droplets during aerosolization is necessary to bring small particles into the scope of detailed structural studies with X-ray lasers.

  18. Spectral Variability in Hard X-rays and the Evidence for a 13.5 Years ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Astrophysics and Astronomy; Volume 23; Issue 3-4 ... This is in complete contrast to the reported data from OSSE and BeppoSAX which suggest the value of 1.3 to 1.6 for the power law index in the X-ray energy band, but is quite consistent with the value derived for the high energy gamma ray ...

  19. Optical control of hard X-ray polarization by electron injection in a laser wakefield accelerator

    Science.gov (United States)

    Schnell, Michael; Sävert, Alexander; Uschmann, Ingo; Reuter, Maria; Nicolai, Maria; Kämpfer, Tino; Landgraf, Björn; Jäckel, Oliver; Jansen, Oliver; Pukhov, Alexander; Kaluza, Malte Christoph; Spielmann, Christian

    2013-01-01

    Laser-plasma particle accelerators could provide more compact sources of high-energy radiation than conventional accelerators. Moreover, because they deliver radiation in femtosecond pulses, they could improve the time resolution of X-ray absorption techniques. Here we show that we can measure and control the polarization of ultra-short, broad-band keV photon pulses emitted from a laser-plasma-based betatron source. The electron trajectories and hence the polarization of the emitted X-rays are experimentally controlled by the pulse-front tilt of the driving laser pulses. Particle-in-cell simulations show that an asymmetric plasma wave can be driven by a tilted pulse front and a non-symmetric intensity distribution of the focal spot. Both lead to a notable off-axis electron injection followed by collective electron–betatron oscillations. We expect that our method for an all-optical steering is not only useful for plasma-based X-ray sources but also has significance for future laser-based particle accelerators. PMID:24026068

  20. Hard x-ray phase contrast imaging using single absorption grating and hybrid semiconductor pixel detector

    Science.gov (United States)

    Krejci, Frantisek; Jakubek, Jan; Kroupa, Martin

    2010-11-01

    A method for x-ray phase contrast imaging is introduced in which only one absorption grating and a microfocus x-ray source in a tabletop setup are used. The method is based on precise subpixel position determination of the x-ray pattern projected by the grating directly from the pattern image. For retrieval of the phase gradient and absorption image (both images obtained from one exposure), it is necessary to measure only one projection of the investigated object. Thus, our method is greatly simplified compared with the phase-stepping method and our method can significantly reduce the time-consuming scanning and possibly the unnecessary dose. Furthermore, the technique works with a fully polychromatic spectrum and gives ample variability in object magnification. Consequently, the approach can open the way to further widespread application of phase contrast imaging, e.g., into clinical practice. The experimental results on a simple testing object as well as on complex biological samples are presented.

  1. The Causal Connection Between Disc and Power-Law Variability in Hard State Black Hole X-Ray Binaries

    Science.gov (United States)

    Uttley, P.; Wilkinson, T.; Cassatella, P.; Wilms, J.; Pottschimdt, K.; Hanke, M.; Boeck, M.

    2010-01-01

    We use the XMM-Newton EPIC-pn instrument in timing mode to extend spectral time-lag studies of hard state black hole X-ray binaries into the soft X-ray band. \\Ve show that variations of the disc blackbody emission substantially lead variations in the power-law emission, by tenths of a second on variability time-scales of seconds or longer. The large lags cannot be explained by Compton scattering but are consistent with time-delays due to viscous propagation of mass accretion fluctuations in the disc. However, on time-scales less than a second the disc lags the power-law variations by a few ms, consistent with the disc variations being dominated by X-ray heating by the power-law, with the short lag corresponding to the light-travel time between the power-law emitting region and the disc. Our results indicate that instabilities in the accretion disc are responsible for continuum variability on time-scales of seconds or longer and probably also on shorter time-scales.

  2. Observation of electric potential in organic thin-film transistor by bias-applied hard X-ray photoemission spectroscopy

    Science.gov (United States)

    Watanabe, Takeshi; Tada, Keisuke; Yasuno, Satoshi; Oji, Hiroshi; Yoshimoto, Noriyuki; Hirosawa, Ichiro

    2016-03-01

    The effect of gate voltage on electric potential in a pentacene (PEN) layer was studied by hard X-ray photoelectron spectroscopy under a bias voltage. It was observed that applying a negative gate voltage substantially increases the width of a C 1s peak. This suggested that injected and accumulated carriers in an organic thin film transistor channel modified the potential depth profile in PEN. It was also observed that the C 1s kinetic energy tends to increase monotonically with threshold voltage.

  3. CdZnTe and CdTe detector arrays for hard X-ray and gamma-ray astronomy

    CERN Document Server

    Stahle, C M; Parsons, A M; Barbier, L M; Barthelmy, S D; Gehrels, N A; Palmer, D M; Snodgrass, S J; Tüller, J

    1999-01-01

    A variety of CdZnTe and CdTe detector arrays were fabricated at NASA/GSFC for use in hard X-ray and gamma-ray astronomy. Mosaic, pixel, and 3-D position-sensitive detector arrays were built to demonstrate the capabilities for high-resolution imaging and spectroscopy for 10 to 2 MeV. This paper will summarize the different arrays and their applications for instruments being developed at NASA/GSFC. Specific topics to be addressed include materials characterization, fabrication of detectors, ASIC readout electronics, and imaging and spectroscopy tests.

  4. Inverse Compton Origin of the Hard X-ray and Soft gamma-ray Emission from the Galactic Ridge

    Energy Technology Data Exchange (ETDEWEB)

    Porter, Troy A.; Moskalenko, Igor V.; Strong, Andrew W.; Orlando, Elena; Bouchet, Laurent

    2008-09-30

    A recent re-determination of the non-thermal component of the hard X-ray to soft {gamma}-ray emission from the Galactic ridge, using the SPI instrument on the INTErnational Gamma-Ray Astrophysics Laboratory (INTEGRAL) Observatory, is shown to be well reproduced as inverse-Compton emission from the interstellar medium. Both cosmic-ray primary electrons and secondary electrons and positrons contribute to the emission. The prediction uses the GALPROP model and includes a new calculation of the interstellar radiation field. This may solve a long-standing mystery of the origin of this emission, and potentially opens a new window on Galactic cosmic rays.

  5. Development and application of cryogenic radiometry with hard X-rays; Entwicklung und Anwendung der Kryoradiometrie mit harter Roentgenstrahlung

    Energy Technology Data Exchange (ETDEWEB)

    Gerlach, Martin

    2008-06-06

    To establish cryogenic radiometry with hard X-ray radiation for photon energies of up to 60 keV, a novel type of cavity absorber had to be developed for the cryogenic radiometer SYRES I, which is deployed by the Physikalisch-Technische Bundesanstalt (PTB) as primary standard detector at the electron storage ring BESSY II. This new type of cavity absorber allows for the complete absorption of hard X-ray radiation in combination with an appropriate sensitivity and an adequate time constant for the measurement of synchrotron radiation at BESSY II. As the process of fabrication of different types of absorbers is very time-consuming, the interaction of hard X-ray radiation with different absorber materials and geometries was studied intensively by using the Monte Carlo simulation code Geant4. The accuracy of the simulations was verified comparing them to scattering experiments performed at a wavelength shifter beamline at BESSY II with a calibrated energy dispersive detector. It was shown that Geant4 describes the photo-effect, including fluorescence as well as Compton- and Rayleigh scattering, with high accuracy. The simulations and experiments resulted in a cavity absorber with a gold base 550 {mu}m in thickness and a cylindrical shell made of copper 90 {mu}m in thickness to reduce losses caused by fluorescence and scattered radiation. Monochromatized synchrotron radiation of high spectral purity was then used to calibrate semiconductor photodiodes, which can be used as compact and inexpensive secondary standard detectors, against a cryogenic radiometer, covering the entire photon energy range of three beamlines from 50 eV to 60 keV with relative uncertainties of less than 0.5 %. Furthermore the spatial homogeneity of the spectral responsivity, the transmittance and the linearity of the photodiodes was investigated. Through a direct comparison of the free-air ionization chamber PK100, a primary detector standard of PTB used in dosimetry, and the cryogenic radiometer

  6. A disk-corona model for low/hard state of black hole X-ray binaries

    OpenAIRE

    Wang, Jiu-Zhou; Wang, Ding-Xiong; Huang, Chang-Yin

    2013-01-01

    A disk-corona model for fitting low/hard (LH) state of associated steady jet of black hole X-ray binaries (BHXBs) is proposed based on the large-scale magnetic field configuration of the coexistence of the Blandford-Znajek (BZ) and Blandford-Payne (BP) processes,where the magnetic field configuration for the BP process is determined by the requirement of energy conversion from Poynting energy flux into kinetic energy flux in the jet. It is found that corona current is crucial to guarantee the...

  7. Broadband X-ray spectra of GX 339-4 and the geometry of accreting black holes in the hard state

    NARCIS (Netherlands)

    Tomsick, J.A.; Kalemci, E.; Kaaret, P.; Markoff, S.; Corbel, S.; Migliari, S.; Fender, R.; Bailyn, C.D.; Buxton, M.M.

    2008-01-01

    A major question in the study of black hole binaries involves our understanding of the accretion geometry when the sources are in the "hard'' state, with an X-ray energy spectrum dominated by a hard power-law component and radio emission coming from a steady "compact'' jet. Although the common hard

  8. First Hard X-Ray Detection of the Non-Thermal Emission Around the Arches Cluster: Morphology and Spectral Studies With NuSTAR

    Science.gov (United States)

    Krivonos, Roman A.; Tomsick, John A.; Bauer, Franz E.; Baganoff, Frederick K.; Barriere, Nicolas M.; Bodaghee, Arash; Boggs, Steven E.; Christensen, Finn E.; Craig, William W.; Grefenstette, Brian W.; hide

    2014-01-01

    The Arches cluster is a young, densely packed massive star cluster in our Galaxy that shows a high level of star formation activity. The nature of the extended non-thermal X-ray emission around the cluster remains unclear. The observed bright Fe K(alpha) line emission at 6.4 keV from material that is neutral or in a low ionization state can be produced either by X-ray photoionization or by cosmic-ray particle bombardment or both. In this paper, we report on the first detection of the extended emission around the Arches cluster above 10 keV with the NuSTAR mission, and present results on its morphology and spectrum. The spatial distribution of the hard X-ray emission is found to be consistent with the broad region around the cluster where the 6.4 keV line is observed. The interpretation of the hard X-ray emission within the context of the X-ray reflection model puts a strong constraint on the luminosity of the possible illuminating hard X-ray source. The properties of the observed emission are also in broad agreement with the low-energy cosmic-ray proton excitation scenario. Key words: cosmic rays - Galaxy: center - ISM: general - X-rays: individual (Arches cluster)

  9. Evaluating scintillator performance in time-resolved hard X-ray studies at synchrotron light sources.

    Science.gov (United States)

    Rutherford, Michael E; Chapman, David J; White, Thomas G; Drakopoulos, Michael; Rack, Alexander; Eakins, Daniel E

    2016-05-01

    The short pulse duration, small effective source size and high flux of synchrotron radiation is ideally suited for probing a wide range of transient deformation processes in materials under extreme conditions. In this paper, the challenges of high-resolution time-resolved indirect X-ray detection are reviewed in the context of dynamic synchrotron experiments. In particular, the discussion is targeted at two-dimensional integrating detector methods, such as those focused on dynamic radiography and diffraction experiments. The response of a scintillator to periodic synchrotron X-ray excitation is modelled and validated against experimental data collected at the Diamond Light Source (DLS) and European Synchrotron Radiation Facility (ESRF). An upper bound on the dynamic range accessible in a time-resolved experiment for a given bunch separation is calculated for a range of scintillators. New bunch structures are suggested for DLS and ESRF using the highest-performing commercially available crystal LYSO:Ce, allowing time-resolved experiments with an interframe time of 189 ns and a maximum dynamic range of 98 (6.6 bits).

  10. Long term hard X-ray variability of the anomalous X-ray pulsar 1RXS J170849.0-400910 discovered with INTEGRAL

    NARCIS (Netherlands)

    Götz, D.; Rea, N.; Israel, G.L.; Zane, S.; Esposito, P.; Gotthelf, E.V.; Mereghetti, S.; Tiengo, A.; Turolla, R.

    2007-01-01

    Aims.We report on a multi-band high-energy observing campaign aimed at studying the long term spectral variability of the Anomalous X-ray Pulsar (AXP) 1RXS J170849.0-400910, one of the magnetar candidates. Methods: We observed 1RXS J170849.0-400910 in Fall 2006 and Spring 2007 simultaneously with

  11. Pronounced Surface Band Bending of Thin-Film Silicon Revealed by Modeling Core Levels Probed with Hard X-rays.

    Science.gov (United States)

    Wippler, David; Wilks, Regan G; Pieters, Bart E; van Albada, Sacha J; Gerlach, Dominic; Hüpkes, Jürgen; Bär, Marcus; Rau, Uwe

    2016-07-13

    Enhancing the probing depth of photoemission studies by using hard X-rays allows the investigation of buried interfaces of real-world device structures. However, it also requires the consideration of photoelectron-signal attenuation when evaluating surface effects. Here, we employ a computational model incorporating surface band bending and exponential photoelectron-signal attenuation to model depth-dependent spectral changes of Si 1s and Si 2s core level lines. The data were acquired from hydrogenated boron-doped microcrystalline thin-film silicon, which is applied in silicon-based solar cells. The core level spectra, measured by hard X-ray photoelectron spectroscopy using different excitation energies, reveal the presence of a 0.29 nm thick surface oxide layer. In the silicon film a downward surface band bending of eVbb = -0.65 eV over ∼6 nm obtained via inverse modeling explains the observed core level shifts and line broadening. Moreover, the computational model allows the extraction of the "real" Si 1s and Si 2s bulk core level binding energies as 1839.13 and 150.39 eV, and their natural Lorentzian line widths as 496 and 859 meV, respectively. These values significantly differ from those directly extracted from the measured spectra. Because band bending usually occurs at material surfaces we highly recommend the detailed consideration of signal integration over depth for quantitative statements from depth-dependent measurements.

  12. IGR J18284-0345: a new hard X-ray transient detected by INTEGRAL

    DEFF Research Database (Denmark)

    Blanchard, T.; Beckmann, V.; Chenevez, Jérôme

    2009-01-01

    The IBIS/ISGRI and the JEM-X1 instrument aboard INTEGRAL discovered a new X-ray source during an observation of the inner Galactic disk conducted from 2009 March 18 at 18:37 UT to March 19, 6:22 UT. The new source, IGR J18284-0345 was detected at RA=277.114, DEC=-3.764 (J2000) in the 20-40 ke...... at 2009 March 20 at 15:58 UT for an effective on source time of 1.9 ksec. Swift/XRT detected one source within the INTEGRAL error circle at RA=277.125, DEC=-3.762 with an uncertainty of 4 arcsec. The spectrum can be fit together with the INTEGRAL data by a black body model with kT = 4.0±0.2 ke...

  13. Deformations and stress in PMMA during hard x-ray exposure for deep lithography.

    Energy Technology Data Exchange (ETDEWEB)

    Moldovan, N.

    1999-08-17

    The availability of high-energy, high-flux, collimated synchrotrons radiation has extended the application of deep X-ray lithography (DXRL) to thickness values of the PMMA resist of several millimeters. Some of the most severe limitations come from plastic deformation, stress, and cracks induced in PMMA during exposure and development. We have observed and characterized these phenomena quantitatively. Profilometry measurements revealed that the PMMA is subjected either to local shrinkage or to expansion, while compression and expansion evolve over time. Due to material loss and crosslinking, the material undergoes a shrinkage, while the radiation-induced decomposition generates gases expanding the polymer matrix. The overall dynamics of the material microrelief and stress during and after the exposure depend on the balance between compaction and outgassing. These depend in turn on the exposure conditions (spectrum; dose, dose rate, seaming, temperature), post-exposure storage conditions, PMMA material properties and thickness, and also on the size and geometry of the exposed patterns.

  14. Single-element elliptical hard x-ray micro-optics.

    Science.gov (United States)

    Evans-Lutterodt, Kenneth; Ablett, James; Stein, Aaron; Kao, Chi-Chang; Tennant, Don; Klemens, Fred; Taylor, Ashley; Jacobsen, Chris; Gammel, Peter; Huggins, Harold; Bogart, Greg; Ustin, Scott; Ocola, Leo

    2003-04-21

    Using micro-fabrication techniques, we have manufactured a single element kinoform lens in single-crystal silicon with an elliptical profile for 12.398 keV (1A) x-rays. By fabricating a lens that is optimized at fixed wavelengths, absorption in the lens material can be significantly reduced by removing 2_ phase-shifting regions. This permits short focal length devices to be fabricated with small radii of curvatures at the lens apex. This feature allows one to obtain a high demagnification of a finite synchrotron electron source size. The reduced absorption loss also enables optics with a larger aperture, and hence improved resolution for focusing and imaging applications. Our first trial of these lenses has resulted in a one micron line focus (fwhm) at the National Synchrotron Light Source X13B beamline.

  15. Hard X-Ray Emission from SH 2-104: A NuSTAR Search for Gamma-Ray Counterparts

    Science.gov (United States)

    Gotthelf, E. V.; Mori, K.; Aliu, E.; Paredes, J. M.; Tomsick, J. A.; Boggs, S. E.; Christensen, F. E.; Craig, W. W.; Hailey, C. J.; Harrison, F. A.; hide

    2016-01-01

    We present NuSTAR hard X-ray observations of Sh 2-104, a compact H II region containing several young massive stellar clusters (YMSCs). We have detected distinct hard X-ray sources coincident with localized VERITAS TeV emission recently resolved from the giant gamma-ray complex MGRO J2019+37 in the Cygnus region. Fainter, diffuse X-rays coincident with the eastern YMSC in Sh2-104 likely result from the colliding winds of a component star. Just outside the radio shell of Sh 2-104 lies 3XMM J201744.7+365045 and a nearby nebula, NuSTAR J201744.3+364812, whose properties are most consistent with extragalactic objects. The combined XMM-Newton and NuSTAR spectrum of 3XMM J201744.7+365045 is well-fit to an absorbed power-law model with N(sub H) = (3.1 +/- 1.0) x 10(exp 22) cm(exp -2) and a photon index gamma = 2.1 +/- 0.1. Based on possible long-term flux variation and the lack of detected pulsations (less than or equal to 43% modulation), this object is likely a background active galactic nucleus rather than a Galactic pulsar. The spectrum of the NuSTAR nebula shows evidence of an emission line at E = 5.6 keV, suggesting an optically obscured galaxy cluster at z = 0.19 +/- 0.02 (d = 800 Mpc) and L(sub X) = 1.2 x 10(exp 44) erg s(exp -1). Follow-up Chandra observations of Sh 2-104 will help identify the nature of the X-ray sources and their relation to MGRO J2019+37. We also show that the putative VERITAS excess south of Sh 2-104, is most likely associated with the newly discovered Fermi pulsar PSR J2017+3625 and not the H II region.

  16. Monitoring the 2010-2015 Hard X-ray/Low-Energy Gamma-Ray Activity of Cygnus X-1 with GBM

    Science.gov (United States)

    Case, Gary L.; Jenke, Peter; Wilson-Hodge, Colleen A.

    2017-08-01

    Cygnus X-1 is a high-mass X-ray binary with a black hole companion that typically resides in a hard spectral state, where it is extremely bright in hard X-rays and low energy gamma rays and much fainter in the soft X-rays. Since 2008 August, we have used the Gamma-Ray Burst Monitor (GBM) on Fermi to monitor Cyg X-1 in the 10-1000 keV energy range using the Earth occultation technique. Starting in the middle of 2010, Cyg X-1 was observed by GBM to enter a period of increased activity, making several transitions to the soft state, characterized by the typical rise in the soft X-ray flux and decrease in the hard x-ray and low energy gamma-ray flux. From the soft state, Cyg X-1 made several transitions to intermediate states as well as several short transitions back to the hard state. At the end of 2015, Cyg X-1 transitioned back to the canonical hard state, where it has remained ever since. We have generated long-term, broad-band light curves based on daily monitoring of Cyg X-1 over a 9 year period showing the hard-to-soft state transitions, the intermediate states, and the soft-to-hard and failed soft-to-hard state transitions. Spectra are presented of Cyg X-1 in the various states and comparisons made between spectra in the same state. The time evolution of the x-ray hardness ratios is also presented.

  17. A Next-Generation Hard X-Ray Nanoprobe Beamline for In Situ Studies of Energy Materials and Devices

    Energy Technology Data Exchange (ETDEWEB)

    Maser, Jong [Argonne National Lab. (ANL), Argonne, IL (United States); Lai, Barry [Argonne National Lab. (ANL), Argonne, IL (United States); Buonassisi, Toni [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Cai, Zhonghou [Argonne National Lab. (ANL), Argonne, IL (United States); Chen, Si [Argonne National Lab. (ANL), Argonne, IL (United States); Finney, Lydia [Argonne National Lab. (ANL), Argonne, IL (United States); Gleber, Sophie-Charlotte [Argonne National Lab. (ANL), Argonne, IL (United States); Jacobsen, Chris [Argonne National Lab. (ANL), Argonne, IL (United States); Preissner, Curt [Argonne National Lab. (ANL), Argonne, IL (United States); Roehrig, Chris [Argonne National Lab. (ANL), Argonne, IL (United States); Rose, Volker [Argonne National Lab. (ANL), Argonne, IL (United States); Shu, Deming [Argonne National Lab. (ANL), Argonne, IL (United States); Vine, David [Argonne National Lab. (ANL), Argonne, IL (United States); Vogt, Stefan [Argonne National Lab. (ANL), Argonne, IL (United States)

    2013-08-20

    The Advanced Photon Source is developing a suite of new X-ray beamlines to study materials and devices across many length scales and under real conditions. One of the flagship beamlines of the APS upgrade is the In Situ Nanoprobe (ISN) beamline, which will provide in situ and operando characterization of advanced energy materials and devices under varying temperatures, gas ambients, and applied fields, at previously unavailable spatial resolution and throughput. Examples of materials systems include inorganic and organic photovoltaic systems, advanced battery systems, fuel cell components, nanoelectronic devices, advanced building materials and other scientifically and technologically relevant systems. To characterize these systems at very high spatial resolution and trace sensitivity, the ISN will use both nanofocusing mirrors and diffractive optics to achieve spots sizes as small as 20 nm. Nanofocusing mirrors in Kirkpatrick–Baez geometry will provide several orders of magnitude increase in photon flux at a spatial resolution of 50 nm. Diffractive optics such as zone plates and/or multilayer Laue lenses will provide a highest spatial resolution of 20 nm. Coherent diffraction methods will be used to study even small specimen features with sub-10 nm relevant length scale. A high-throughput data acquisition system will be employed to significantly increase operations efficiency and usability of the instrument. The ISN will provide full spectroscopy capabilities to study the chemical state of most materials in the periodic table, and enable X-ray fluorescence tomography. In situ electrical characterization will enable operando studies of energy and electronic devices such as photovoltaic systems and batteries. We also describe the optical concept for the ISN beamline, the technical design, and the approach for enabling a broad variety of in situ studies. Furthermore, we discuss the application of hard X-ray microscopy to study defects in multi-crystalline solar

  18. Spherical analyzers and monochromators for resonant inelastic hard X-ray scattering: a compilation of crystals and reflections

    Energy Technology Data Exchange (ETDEWEB)

    Gog, Thomas, E-mail: gog@aps.anl.gov; Casa, Diego M.; Said, Ayman H.; Upton, Mary H.; Kim, Jungho; Kuzmenko, Ivan; Huang, XianRong; Khachatryan, Ruben [Advanced Photon Source, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States)

    2013-01-01

    Resonant inelastic X-ray scattering (RIXS) experiments require special sets of near-backscattering spherical diced analyzers and high-resolution monochromators for every distinct absorption-edge energy or emission line. For the purpose of aiding the design and planning of efficient RIXS experiments, a compilation of suitable crystal materials and viable reflections for hard X-rays, together with energy resolution and throughput information, is presented. Resonant inelastic X-ray scattering (RIXS) experiments require special sets of near-backscattering spherical diced analyzers and high-resolution monochromators for every distinct absorption-edge energy and emission line. For the purpose of aiding the design and planning of efficient RIXS experiments, comprehensive lists of suitable analyzer reflections for silicon, germanium, α-quartz, sapphire and lithium niobate crystals were compiled for a multitude of absorption edges and emission lines. Analyzers made from lithium niobate, sapphire or α-quartz offer many choices of reflections with intrinsic resolutions currently unattainable from silicon or germanium. In some cases these materials offer higher intensities at comparable resolutions. While lithium niobate, sapphire or α-quartz analyzers are still in an early stage of development, the present compilation can serve as a computational basis for assessing expected and actual performance. With regard to high-resolution monochromators, bandpass and throughput calculations for combinations of double-crystal, high-heat-load and near-backscattering high-resolution channel-cuts were assembled. The compilation of these analyzer and monochromator data is publicly available on a website.

  19. Spatially resolving a starburst galaxy at hard X-ray energies: NuSTAR, CHANDRA, AND VLBA observations of NGC 253

    DEFF Research Database (Denmark)

    Wik, D. R.; Lehmer, B. D.; Hornschemeier, A. E.

    2014-01-01

    Prior to the launch of NuSTAR, it was not feasible to spatially resolve the hard (E > 10 keV) emission from galaxies beyond the Local Group. The combined NuSTAR data set, comprised of three ~165 ks observations, allows spatial characterization of the hard X-ray emission in the galaxy NGC 253 for ...

  20. Analysis of hard X-ray emission from selected very high energy {gamma}-ray sources observed with INTEGRAL

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, Agnes Irene Dorothee

    2009-11-13

    A few years ago, the era of very high energy {gamma}-ray astronomy started, when the latest generation of Imaging Atmospheric Cherenkov Telescopes (IACT) like H.E.S.S. began to operate and to resolve the sources of TeV emission. Identifications via multi-wavelength studies reveal that the detected sources are supernova remnants and active galactic nuclei, but also pulsar wind nebulae and a few binaries. One widely discussed open question is, how these sources are able to accelerate particles to such high energies. The understanding of the underlying particle distribution, the acceleration processes taking place, and the knowledge of the radiation processes which produce the observed emission, is, therefore, of crucial interest. Observations in the hard X-ray domain can be a key to get information on these particle distributions and processes. Important for this thesis are the TeV and the hard X-ray range. The two instruments, H.E.S.S. and INTEGRAL, whose data were used, are, therefore, described in detail. The main part of this thesis is focused on the X-ray binary system LS 5039/RX J1826.2-1450. It was observed in several energy ranges. The nature of the compact object is still not known, and it was proposed either to be a microquasar system or a non-accreting pulsar system. The observed TeV emission is modulated with the orbital cycle. Several explanations for this variability have been discussed in recent years. The observations with INTEGRAL presented in this thesis have provided new information to solve this question. Therefore, a search for a detection in the hard X-ray range and for its orbital dependence was worthwhile. Since LS 5039 is a faint source and the sky region where it is located is crowded, a very careful, non-standard handling of the INTEGRAL data was necessary, and a cross-checking with other analysis methods was essential to provide reliable results. We found that LS 5039 is emitting in the hard X-ray energy range. A flux rate and an upper

  1. Ultra-long Duration Balloon Mission Concept Study: EXIST-LITE Hard X-ray Imaging Survey

    Science.gov (United States)

    2003-01-01

    We carried out a mission concept Study for an ultra-long duration balloon (ULDB) mission to conduct a high-sensitivity hard x-ray (approx. 20-600 keV) imaging sky survey. The EXIST-LITE concept has been developed, and critical detector technologies for realistic fabrication of very large area Cd-Zn-Te imaging detector arrays are now much better understood. A ULDB mission such as EXIST-LITE is now even more attractive as a testbed for the full Energetic X-ray Imaging Survey Telescope (EXIST) mission, recommended by the Decadal Survey, and now included in the NASA Roadmap and Strategic Plan as one of the 'Einstein Probes'. In this (overdue!) Final Report we provide a brief update for the science opportunities possible with a ULDB mission such as EXIST-LITE and relate these to upcoming missions (INTErnational Gamma-Ray Astrophysics Laboratory (INTEGRAL) and Swift) as well as the ultimate very high sensitivity sky survey mission EXIST. We then review the progress made over this investigation in Detector/Telescope design concept, Gondola and Mission design concept, and Data Handling/Analysis.

  2. Bent Crystals By Superficial Grooves For High-efficiency Concentration Of Hard X-ray Photons By A Laue Lens

    Science.gov (United States)

    Guidi, V.; Bellucci, V.; Camattari, R.; Neri, I.

    2011-09-01

    We propose a technique to fabricate self-standing curved crystals for high-efficiency concentration of hard X-ray photons by a Laue lens. This technique relies on superficial grooves on a mono- crystal by a diamond saw. Extension of the method to materials with higher atomic number, e.g., Ge, has been undertaken to provide high-efficiency diffraction up to 800 keV. With respect to other proposed techniques, the method of indentations is cheap, simple and reproducible, being based on mass production tools. It is possible to use curved crystal in two different geometries. Employing the ``geometry one'', it is possible to exploit the curvature directly imparted to the crystal to achieve high-efficiency diffraction. Grooved Si crystals were characterized in this geometry at ESRF and efficiently diffracted up to 500 keV, peaking 95% at 150 keV. The ``geometry two'' consists in exploiting the so-called quasi-mosaicity to obtain high-resolution focusing of X-rays. As a result of primary curvature imparted to the crystal, a secondary curvature (Quasi-Mosaic curvature) occurs. We demonstrated that a combination of primary and quasi-mosaic curvatures allows high-efficiency diffraction and high-resolution focusing of diffracted photons. Quasi-Mosaic crystals would increases the signal-to-noise ratio of about one orders of magnitude with respect to mosaic crystals and no mosaic defocusing would occur.

  3. Multimodal hard x-ray nanoprobe facility by nested Montel mirrors aimed for 40nm resolution at Taiwan Photon Source

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Gung-Chian, E-mail: gcyin@nsrrc.org.tw; Chang, Shi-Hung; Chen, Bo-Yi; Chen, Huang-Yeh; Lin, Bi-Hsuan; Tseng, Shao-Chin; Lee, Chian-Yao; Tang, Mau-Tsu [National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan (China); Wu, Shao-Yun [National Tsing-Hua University, Hsinchu 30076, Taiwan (China)

    2016-01-28

    The hard X-ray nanoprobe facility at Taiwan Photon Source (TPS) provides multimodal X-ray detections, including XRF, XAS, XEOL, projection microscope, CDI, etc. Resulting from the large numerical aperture obtained by utilizing nested Montel mirrors, the beamline with a moderate length 75 meters can conduct similar performance with those beamlines longer than 100 meters. The mirrors are symmetrically placed with a 45 degrees cut. The beamline optics is thus designed to take the advantage of the symmetry of mirrors such that a round focal spot is accomplished. The size and the divergence of the focus spot are simulated around 40 nm and 6.29 mrad, respectively. The whole facility including the beamline and the stations will be operated under vacuum to preserve the photon coherence as well as to prevent the system from unnecessary environmental interference. A SEM in close cooperation with laser interferometers is equipped to precisely locate the position of the sample. This endstation is scheduled to be commissioned in the fall of 2016.

  4. A low cost method for hard x-ray grating interferometry

    Science.gov (United States)

    Du, Yang; Lei, Yaohu; Liu, Xin; Huang, Jianheng; Zhao, Zhigang; Guo, Jinchuan; Li, Ji; Niu, Hanben

    2016-12-01

    Grating interferometry is advantageous over conventional x-ray absorption imaging because it enables the detection of samples constituted by low atomic number elements (low-Z materials). Therefore, it has a potential application in biological science and medical diagnostics. The grating interferometry has some critical optics components such as absorption gratings which are conventionally manufactured by the lithography, electroplating, and molding (LIGA) technique and employing gold as the absorbent material in it. However, great challenge lies in its implementations for practical applications because of the cost and difficulty to achieve high aspect ratio absorbing grating devices. In this paper, we present a low-cost approach that involves using the micro-casting technique with bismuth (Bi) as the absorber in source grating and as well as filling cesium iodide thallium(CsI:Tl) in a periodically structured scintillator. No costly facilities as synchrotron radiation are required and cheap material is used in our approach. Our experiment using these components shows high quality complementary images can be obtained with contrast of absorption, phase and visibility. This alternative method conquers the limitation of costly grating devices for a long time and stands an important step towards the further practical application of grating interferometry.

  5. A new hard X-ray source discovered by INTEGRAL: IGR J16442-554

    DEFF Research Database (Denmark)

    Bozzo, E.; Ferrigno, C.; Chenevez, Jérôme

    2009-01-01

    During a key program observation of the inner Galactic disc performed between 2009-08-30 14:04 and 2009-09-01 12:03 (UTC), a new source was discovered in the INTEGRAL/IBIS mosaic image. The best localization is RA: 251.088 DEC: -55.808, with a 90% error radius of 3.6 arcmin. The source, IGR J16442......-5548, is detected with a significance of 7 sigma in the 20-40 keV energy band and of 5 sigma in the 40-100 keV energy band. The corresponding flux is about 7 mCrab. The source is not detected in the JEM-X monitor: upper limits at 3 sigma c.l. are respectively 2 and 5 mCrab in the 3-10 keV and 10-25 keV energy bands....... The IBIS/ISGRI spectrum in the 20-100 keV energy range is well described by a power-law with photon index 2.2+/-0.5. The 20-100 keV flux is 1.2e-10 erg/cm^2/s. The light curve exhibits pronounced variability on a few hours time scale. We did not find any previously known X-ray source in the Simbad database...

  6. A comparison of classical histology to anatomy revealed by hard x-rays

    Science.gov (United States)

    Richter, Claus-Peter; Tan, Xiaodong; Young, Hunter; Stock, Stuart; Robinson, Alan; Byskosh, Orest; Zheng, Jing; Soriano, Carmen; Xiao, Xianghui; Whitlon, Donna

    2016-10-01

    Many diseases trigger morphological changes in affected tissue. Today, classical histology is still the "gold standard" used to study and describe those changes. Classical histology, however, is time consuming and requires chemical tissue manipulations that can result in significant tissue distortions. It is sometimes difficult to separate tissue-processing artifacts from changes caused by the disease process. We show that synchrotron X-ray phase-contrast micro-computed tomography (micro-CT) can be used to examine non-embedded, hydrated tissue at a resolution comparable to that obtained with classical histology. The data analysis from stacks of reconstructed micro-CT images is more flexible and faster than when using the classical, physically embedded sections that are by necessity fixed in a particular orientation. We show that in a three-dimensional (3D) structure with meticulous structural details such as the cochlea and the kidney, micro-CT is more flexible, faster and more convenient for morphological studies and disease diagnoses.

  7. Quasi-mosaic Crystals For High-resolution Focusing Of Hard X-rays Through A Laue Lens

    Science.gov (United States)

    Camattari, R.; Guidi, V.; Bellucci, V.; Neri, I.

    2011-09-01

    We propose the usage of bent crystals exploiting the Quasi-Mosaicity for high-resolution focusing of hard X-rays. Quasi-Mosaicity is an effect of anisotropy in crystals that manifests itself along selected crystallographic directions. As a result of primary curvature imparted to the crystal, a secondary curvature (Quasi-Mosaic curvature) occurs. We demonstrated that a combination of primary and Quasi-Mosaic curvatures allows high-efficiency diffraction and high-resolution focusing of diffracted photons. As compared to traditional mosaic crystals with same size and energy passband, Quasi-Mosaic crystals would increases the signal-to-noise ratio by about an order of magnitude and no mosaic defocusing would occur.

  8. Structure determination of a multilayer with an island-like overlayer using hard x-ray photoelectron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Isomura, N., E-mail: isomura@mosk.tytlabs.co.jp; Kataoka, K.; Horibuchi, K.; Dohmae, K.; Kitazumi, K.; Takahashi, N.; Kimoto, Y. [Toyota Central R& D Laboratories, Inc., 41-1 Yokomichi, Nagakute, Aichi 480-1192 (Japan); Oji, H.; Cui, Y.-T.; Son, J.-Y. [Japan Synchrotron Radiation Research Institute (JASRI), 1-1-1 Kouto, Sayo, Hyogo 679-5198 (Japan)

    2016-07-27

    We use hard X-ray photoelectron spectroscopy (HAXPES) to obtain the surface structure of a multilayer Au/SiO{sub 2}/Si substrate sample with an island-like overlayer. Photoelectron intensities are measured as a function of incident photon energy (PE) and take-off angle (TOA, measured from the sample surface). The Au layer coverage and Au and SiO{sub 2} layer thicknesses are obtained by the PE dependence, and are used for the following TOA analysis. The Au island lateral width in the cross section is obtained by the TOA dependence, including information about surface roughness, in consideration of the island shadowing at small TOAs. In both cases, curve-fitting analysis is conducted. The surface structure, which consists of layer thicknesses, overlayer coverage and island width, is determined nondestructively by a combination of PE and TOA dependent HAXPES measurements.

  9. A disk-corona model for the low/hard state of black hole X-ray binaries

    Science.gov (United States)

    Wang, Jiu-Zhou; Wang, Ding-Xiong; Huang, Chang-Yin

    2013-10-01

    A disk-corona model for fitting the low/hard (LH) state of the associated steady jet in black hole X-ray binaries (BHXBs) is proposed based on the large-scale magnetic field configuration that arises from the coexistence of the Blandford-Znajek (BZ) and Blandford-Payne (BP) processes, where the magnetic field configuration for the BP process is determined by the requirement of energy conversion from Poynting energy flux into kinetic energy flux in the jet. It is found that corona current is crucial to guarantee the consistency of the jet launching from the accretion disk. The relative importance of the BZ and BP processes in powering jets from black hole accretion disks is discussed, and the LH state of several BHXBs is fitted based on our model. In addition, we suggest that magnetic field configuration can be regarded as the second parameter for governing the state transition of BHXBs.

  10. X-RAY VARIABILITY AND HARDNESS OF ESO 243-49 HLX-1: CLEAR EVIDENCE FOR SPECTRAL STATE TRANSITIONS

    Energy Technology Data Exchange (ETDEWEB)

    Servillat, Mathieu [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-67, Cambridge, MA 02138 (United States); Farrell, Sean A. [Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom); Lin Dacheng; Godet, Olivier; Barret, Didier; Webb, Natalie A., E-mail: mservillat@cfa.harvard.edu [Universite de Toulouse, Universite Paul Sabatier-Observatoire Midi-Pyrenees, Institut de Recherche en Astrophysique et Planetologie (IRAP), Toulouse (France)

    2011-12-10

    The ultraluminous X-ray (ULX) source ESO 243-49 HLX-1, which reaches a maximum luminosity of 10{sup 42} erg s{sup -1} (0.2-10 keV), currently provides the strongest evidence for the existence of intermediate-mass black holes (IMBHs). To study the spectral variability of the source, we conduct an ongoing monitoring campaign with the Swift X-ray Telescope (XRT), which now spans more than two years. We found that HLX-1 showed two fast rise and exponential decay type outbursts in the Swift XRT light curve with increases in the count rate of a factor {approx}40 separated by 375 {+-} 13 days. We obtained new XMM-Newton and Chandra dedicated pointings that were triggered at the lowest and highest luminosities, respectively. From spectral fitting, the unabsorbed luminosities ranged from 1.9 Multiplication-Sign 10{sup 40} to 1.25 Multiplication-Sign 10{sup 42} erg s{sup -1}. We confirm here the detection of spectral state transitions from HLX-1 reminiscent of Galactic black hole binaries (GBHBs): at high luminosities, the X-ray spectrum showed a thermal state dominated by a disk component with temperatures of 0.26 keV at most, and at low luminosities the spectrum is dominated by a hard power law with a photon index in the range 1.4-2.1, consistent with a hard state. The source was also observed in a state consistent with the steep power-law state, with a photon index of {approx}3.5. In the thermal state, the luminosity of the disk component appears to scale with the fourth power of the inner disk temperature, which supports the presence of an optically thick, geometrically thin accretion disk. The low fractional variability (rms of 9% {+-} 9%) in this state also suggests the presence of a dominant disk. The spectral changes and long-term variability of the source cannot be explained by variations of the beaming angle and are not consistent with the source being in a super-Eddington accretion state as is proposed for most ULX sources with lower luminosities. All this

  11. First hard X-ray detection of the non-thermal emission around the Arches cluster: morphology and spectral studies with NuSTAR

    DEFF Research Database (Denmark)

    Krivonos, Roman A.; Tomsick, John A.; Bauer, Franz E.

    2014-01-01

    The Arches cluster is a young, densely packed massive star cluster in our Galaxy that shows a high level of star formation activity. The nature of the extended non-thermal X-ray emission around the cluster remains unclear. The observed bright Fe Ku line emission at 6.4 keV from material that is n......The Arches cluster is a young, densely packed massive star cluster in our Galaxy that shows a high level of star formation activity. The nature of the extended non-thermal X-ray emission around the cluster remains unclear. The observed bright Fe Ku line emission at 6.4 keV from material...... that is neutral or in a low ionization state can be produced either by X-ray photoionization or by cosmic-ray particle bombardment or both. In this paper, we report on the first detection of the extended emission around the Arches cluster above 10 keV with the NuSTAR mission, and present results on its morphology...... and spectrum. The spatial distribution of the hard X-ray emission is found to be consistent with the broad region around the cluster where the 6.4 keV line is observed. The interpretation of the hard X-ray emission within the context of the X-ray reflection model puts a strong constraint on the luminosity...

  12. Scanning hard X-ray microscope with tantalum phase zone plate at the Hyogo-BL (BL24XU) of SPring-8

    CERN Document Server

    Kagoshima, Y; Ibuki, T; Yokoyama, Y; Hashida, T; Yokoyama, K; Takeda, S; Urakawa, M; Miyamoto, N; Tsusaka, Y; Matsui, J; Aino, M

    2001-01-01

    A scanning hard X-ray microscope using a phase zone plate made of tantalum as its X-ray focusing device is in operation at the Hyogo-BL (BL24XU) of SPring-8. The X-ray microbeam has a size of 0.8 mu mx0.7 mu m at the photon energy of 10 keV, which can make visible structures as fine as 250-nm line-and-space pattern. The photon flux density at the sample position is approx 2x10 sup 9 phs/s/mu m sup 2 and the gain of the phase zone plate is approx 3000. The minimum detection limits irradiated by the microbeam are evaluated to be around 10 ppm for some trace elements contained in standard reference materials of glass matrices. X-ray images obtained so far demonstrate a high feasibility of the microscope.

  13. X-Ray Timing Analysis of Cyg X-3 Using AstroSat/LAXPC: Detection of Milli-hertz Quasi-periodic Oscillations during the Flaring Hard X-Ray State

    Science.gov (United States)

    Pahari, Mayukh; Antia, H. M.; Yadav, J. S.; Verdhan Chauhan, Jai; Agrawal, P. C.; Misra, Ranjeev; Chitnis, V. R.; Dedhia, Dhiraj; Katoch, Tilak; Madhwani, P.; Manchanda, R. K.; Paul, B.; Shah, Parag

    2017-11-01

    We present here results from the X-ray timing and spectral analysis of the X-ray binary Cyg X-3 using observations from the Large Area X-ray proportional Counter on board AstroSat. Consecutive light curves observed over a period of one year show the binary orbital period of 17253.56 ± 0.19 s. Another low-amplitude, slow periodicity of the order of 35.8 ± 1.4 days is observed, which may be due to the orbital precession as suggested earlier by Molteni et al. During the rising binary phase, power density spectra from different observations during the flaring hard X-ray state show quasi-periodic oscillations (QPOs) at ˜5-8 mHz, ˜12-14 mHz, and ˜18-24 mHz frequencies at the minimum confidence of 99%. However, during the consecutive binary decay phase, no QPO is detected up to 2σ significance. Energy-dependent time-lag spectra show soft lag (soft photons lag hard photons) at the mHz QPO frequency and the fractional rms of the QPO increases with the photon energy. During the binary motion, the observation of mHz QPOs during the rising phase of the flaring hard state may be linked to the increase in the supply of the accreting material in the disk and corona via stellar wind from the companion star. During the decay phase, the compact source moves in the outer wind region causing the decrease in supply of material for accretion. This may cause weakening of the mHz QPOs below the detection limit. This is also consistent with the preliminary analysis of the orbital phase-resolved energy spectra presented in this paper.

  14. Identification of the Hard X-Ray Source Dominating the E > 25 keV Emission of the Nearby Galaxy M31

    Science.gov (United States)

    Yukita, M.; Ptak, A.; Hornschemeier, A. E.; Wik, D.; Maccarone, T. J.; Pottschmidt, K.; Zezas, A.; Antoniou, V.; Ballhausen, R.; Lehmer, B. D.; hide

    2017-01-01

    We report the identification of a bright hard X-ray source dominating the M31 bulge above 25 keV from a simultaneous NuSTAR-Swift observation. We find that this source is the counterpart to Swift J0042.6+4112, which was previously detected in the Swift BAT All-Sky Hard X-Ray Survey. This Swift BAT source had been suggested to be the combined emission from a number of point sources; our new observations have identified a single X-ray source from 0.5 to 50 keV as the counterpart for the first time. In the 0.5-10 keV band, the source had been classified as an X-ray Binary candidate in various Chandra and XMM-Newton studies; however, since it was not clearly associated with Swift J0042.6+4112, the previous E is less than 10keVobservations did not generate much attention. This source has a spectrum with a soft X-ray excess (kT approximately equal to 0.2 keV) plus a hard spectrum with a power law of gamma approximately equal to 1 and a cutoff around 15-20 keV, typical of the spectral characteristics of accreting pulsars. Unfortunately, any potential pulsation was undetected in the NuSTAR data, possibly due to insufficient photon statistics. The existing deep HST (Hubble Space Telescope) images exclude high-mass (greater than 3 times the radius of the moon) donors at the location of this source. The best interpretation for the nature of this source is an X-ray pulsar with an intermediate-mass (less than 3 times the radius of the moon M) companion or a symbiotic X-ray binary. We discuss other possibilities in more detail.

  15. Hard X-ray polarimetry with position sensitve germanium detectors. Studies of the recombination transitions into highly charged ions

    Energy Technology Data Exchange (ETDEWEB)

    Tashenov, Stanislav

    2005-07-01

    In this work a first study of the photon polarization for the process of radiative recombination has been performed. This was done at the ESR storage ring at GSI for uranium ions colliding with N2 at various collision energies. For this measurement a high purity Ge Pixel Detector with a 4 x 4 segmentation matrix was applied. The investigation was performed at the Gas-jet target of the ESR. The detector was placed at 60 and 90 observation angles. The sensitivity of the Compton scattering effect to the linear polarization of the X-Ray radiation was employed for the polarization measurement. Detailed investigations of the scattering and geometrical effects inside the detector were performed in order to develop a method to interpret the experimental data and extract the degree of the linear polarization in the hard X-Ray regime with a high precision. A special emphasis was given to the geometry of the detector and it's influence on the measured pixel-to-pixel Compton scattering intensities. The developed method enabled to achieve a precision of the order of 10% with the Pixel Detector which is dominated by the statistical uncertainties. The obtained results show a good agreement with the theoretical values derived from the exact relativistic calculations. For the case of the linear polarization of the K-REC photons, the measured data con rm the theoretical prediction that strong depolarization effects occur for high projectile charges in the forward hemisphere. The latter is in disagreement with the nonrelativistic theory which predicts a 100 % polarization regardless of the emission angle. (orig.)

  16. Angle-dependent hard X-ray photoemission study of Nb hydride formation in high-pressure supercritical water

    Energy Technology Data Exchange (ETDEWEB)

    Soda, Kazuo, E-mail: j45880a@cc.nagoya-u.ac.jp [Department of Quantum Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Kondo, Hiroki; Yamaguchi, Kanta; Kato, Masahiko [Department of Quantum Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Shiraki, Tatsuhito; Niwa, Ken; Kusaba, Keiji; Hasegawa, Masashi [Department of Crystalline Materials Science, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Xeniya, Kozina; Ikenaga, Eiji [Japan Synchrotron Radiation Research Institute, 1-1-1, Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan)

    2015-09-15

    Highlights: • Nb hydrides in 10-GPa supercritical water are studied by photoelectron spectroscopy. • The hydride components of the Nb 3d core-level spectra are increased with the depth. • The bulk valence-band spectrum shows a split band due to the Nb–H bond formation. • The hydrides are formed in the bulk and their surfaces are covered with Nb oxides. - Abstract: Nb hydrides formation in 10-GPa supercritical water has been investigated by angle-dependent micro-beam hard X-ray photoemission spectroscopy. In the Nb 3d core-level spectra, Nb hydride components are found in the slightly high binding energy side of the metallic components, and the oxide ones are observed even though little oxides are recognized in X-ray diffraction patterns. Obtained emission-angle dependence of the Nb 3d core-level spectra of Nb hydride specimens shows that the Nb hydride components increase with the emission angle decreased i.e. the sampling depth increased, while the oxide ones decrease. The bulk valence-band spectrum is obtained by decomposing the measured valence-band spectra into a bulk and surface components with use of the emission-angle dependence of the core-level and valence-band spectra; it consists of two bands. This implies the Nb–H chemical bond formation and Nb in an oxidation state, consistent with reported band structure calculations and the observed core-level chemical shifts. Thus it is confirmed by valence-band and core-level photoelectron spectroscopy that the Nb hydrides are formed inside the specimen, irrespective to the well-known high oxidation ability of supercritical water.

  17. Soft x-ray reflectometry, hard x-ray photoelectron spectroscopy and transmission electron microscopy investigations of the internal structure of TiO2(Ti/SiO2/Si stacks

    Directory of Open Access Journals (Sweden)

    Elena O Filatova, Igor V Kozhevnikov, Andrey A Sokolov, Evgeniy V Ubyivovk, Sergey Yulin, Mihaela Gorgoi and Franz Schäfers

    2012-01-01

    Full Text Available We developed a mathematical analysis method of reflectometry data and used it to characterize the internal structure of TiO2/SiO2/Si and Ti/SiO2/Si stacks. Atomic concentration profiles of all the chemical elements composing the samples were reconstructed from the analysis of the reflectivity curves measured versus the incidence angle at different soft x-ray reflection (SXR photon energies. The results were confirmed by the conventional techniques of hard x-ray photoelectron spectroscopy (HXPES and high-resolution transmission electron microscopy (HRTEM. The depth variation of the chemical composition, thicknesses and densities of individual layers extracted from SXR and HXPES measurements are in close agreement and correlate well with the HRTEM images.

  18. INTEGRAL detects Swift J1910.2-0546 (= MAXI J1910-057) in the hard X-rays

    DEFF Research Database (Denmark)

    Bodaghee, A.; Bozzo, E.; Tomsick, J. A.

    2012-01-01

    The black hole candidate Swift J1910.2-0546 (= MAXI J1910-057), which was reported to be transitioning to the hard state (ATels #4273, #4295), was in the field of view of INTEGRAL's hard X-ray imager ISGRI during observations of the Scutum/Sagittarius region performed from 2012 August 20 at 23......:28:03 to August 21 at 03:09:59 UTC (INTEGRAL revolution 1203). A mosaic image combining 12.6 ks of data reveals that Swift J1910.2-0546 is detected by ISGRI at a significance level of 13.7 sigma in the 18--40 keV energy band and at 9.4 sigma in the 40--100 keV energy band. Source count rates in these bands are 15...... curves and images of this source (and others in the field) can be found at the ISA project home page: http://sprg.ssl.berkeley.edu/~bodaghee/isa We thank the ISDC shift team for alerting us to the presence of Swift J1910.2-0546 in our observations and for their help in analyzing the data....

  19. Simultaneous optical/X-ray study of GS 1354-64 (=BW Cir) during hard outburst: evidence for optical cyclo-synchrotron emission from the hot accretion flow

    Science.gov (United States)

    Pahari, Mayukh; Gandhi, Poshak; Charles, Philip A.; Kotze, Marissa M.; Altamirano, Diego; Misra, Ranjeev

    2017-07-01

    We present results from simultaneous optical [South African Large Telescope (SALT)] and X-ray (Swift and INTEGRAL) observations of GS 1354-64/BW Cir during the 2015 hard state outburst. During the rising phase, optical/X-ray time series shows a strong anti-correlation with X-ray photons lagging optical. Optical and X-ray power spectra show quasi-periodic oscillations (QPOs) at a frequency of ˜18 mHz with a confidence level of at least 99 per cent. Simultaneous fitting of Swift/XRT and INTEGRAL spectra in the range 0.5-1000.0 keV shows non-thermal, power-law-dominated (>90 per cent) spectra with a hard power-law index of 1.48 ± 0.03, inner disc temperature of 0.12 ± 0.01 keV and an inner disc radius of ˜3000 km. All evidence is consistent with cyclo-synchrotron radiation in a non-thermal, hot electron cloud extending to ˜100 Schwarzschild radii being a major physical process for the origin of optical photons. At outburst peak about one month later, when the X-ray flux rises and the optical drops, the apparent features in the optical/X-ray correlation vanish and the optical auto correlation widens. Although ˜0.19 Hz QPO is observed from the X-ray power spectra, the optical variability is dominated by the broad-band noise, and the inner disc temperature increases. These results support a change in the dominant optical emission source between outburst rise and peak, consistent with a weakening of hot flow as the disc moves in.

  20. Study of electron beams within ISTTOK tokamak by means of a multi-channel Cherenkov detector; their correlation with hard X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Jakubowski, L., E-mail: Lech.Jakubowski@ipj.gov.p [Andrzej Soltan Institute for Nuclear Studies, 05-400 Otwock-Swierk (Poland); Malinowski, K.; Sadowski, M.J.; Zebrowski, J. [Andrzej Soltan Institute for Nuclear Studies, 05-400 Otwock-Swierk (Poland); Plyusnin, V.V. [Association Euratom/IST, Instituto de Plasmas e Fusao Nuclear, Instituto Superior Tecnico, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Rabinski, M. [Andrzej Soltan Institute for Nuclear Studies, 05-400 Otwock-Swierk (Poland); Fernandes, H.; Silva, C.; Duarte, P. [Association Euratom/IST, Instituto de Plasmas e Fusao Nuclear, Instituto Superior Tecnico, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Jakubowski, M.J. [Andrzej Soltan Institute for Nuclear Studies, 05-400 Otwock-Swierk (Poland)

    2010-11-11

    The paper describes experimental studies of electron beams emitted from a plasma torus within the ISTTOK tokamak, which were performed by means of a new four-channel detector of the Cherenkov type. A range of electron energy was estimated. There were also measured hard X-rays, and their correlation with the fast run-away electron beams was investigated experimentally.

  1. Low-charge, hard x-ray free electron laser driven with an X-band injector and accelerator

    Directory of Open Access Journals (Sweden)

    Yipeng Sun (孙一鹏

    2012-03-01

    Full Text Available After the successful operation of the Free Electron Laser in Hamburg (FLASH and the Linac Coherent Light Source (LCLS, soft and hard x-ray free electron lasers (FELs are being built, designed, or proposed at many accelerator laboratories. Acceleration employing lower frequency rf cavities, ranging from L-band to C-band, is usually adopted in these designs. In the first stage bunch compression, higher-frequency harmonic rf system is employed to linearize the beam’s longitudinal phase space, which is nonlinearly chirped during the lower frequency rf acceleration process. In this paper, a hard x-ray FEL design using an all X-band accelerator at 11.424 GHz (from photocathode rf gun to linac end is presented, without the assistance of any harmonic rf linearization. It achieves LCLS-like performance at low charge using X-band linac drivers, which is more versatile, efficient, and compact than ones using S-band or C-band rf technology. It employs initially 42 microns long (rms, low-charge (10 pC electron bunches from an X-band photoinjector. An overall bunch compression ratio of roughly 100 times is proposed in a two stage bunch compressor system. The start-to-end macroparticle 3D simulation employing several computer codes is presented in this paper, where space charge, wakefields, and incoherent and coherent synchrotron radiation effects are included. Employing an undulator with a short period of 1.5 cm, a Genesis FEL simulation shows successful lasing at a wavelength of 0.15 nm with a pulse length of 2 fs and a power saturation length as short as 20 meters, which is equivalent to LCLS low-charge mode. Its overall length of both accelerators and undulators is 180 meters (much shorter than the effective LCLS overall length of 1230 meters, including an accelerator length of 1100 meters and an undulator length of 130 meters, which makes it possible to be built in places where only limited space is available.

  2. Development of an XSPEC-Based Spectral Analysis System for the Coded-Aperture Hard X-ray Balloon Payload EXITE2

    OpenAIRE

    Bloser, P.F.; Chou, Y.; Grindlay, J.E.; Narita, T.; Monnelly, G.

    2001-01-01

    We present the spectral analysis system for the second-generation Energetic X-ray Imaging Telescope Experiment (EXITE2) balloon payload. EXITE2 is an imaging hard X-ray telescope using a coded-aperture mask and a NaI/CsI phoswich detector operating in the energy range 20--600 keV. The instrument was flown on a high-altitude scientific balloon from Ft. Sumner, NM on 1997 May 7-8. We describe the details of the EXITE2 spectral analysis system, with emphasis on those aspects peculiar to coded-ap...

  3. Comparison of three types of XPAD3.2/CdTe single chip hybrids for hard X-ray applications in material science and biomedical imaging

    Science.gov (United States)

    Buton, C.; Dawiec, A.; Graber-Bolis, J.; Arnaud, K.; Bérar, J. F.; Blanc, N.; Boudet, N.; Clémens, J. C.; Debarbieux, F.; Delpierre, P.; Dinkespiler, B.; Gastaldi, T.; Hustache, S.; Morel, C.; Pangaud, P.; Perez-Ponce, H.; Vigeolas, E.

    2014-09-01

    The CHIPSPECT consortium aims at building a large multi-modules CdTe based photon counting detector for hard X-ray applications. For this purpose, we tested nine XPAD3.2 single chip hybrids in various configurations (i.e. Ohmic vs. Schottky contacts or electrons vs. holes collection mode) in order to select the most performing and best suited configuration for our experimental requirements. Measurements have been done using both X-ray synchrotron beams and 241Am source. Preliminary results on the image quality, calibration, stability, homogeneity and linearity of the different types of detectors are presented.

  4. Comparison of three types of XPAD3.2/CdTe single chip hybrids for hard X-ray applications in material science and biomedical imaging

    Energy Technology Data Exchange (ETDEWEB)

    Buton, C., E-mail: clement.buton@synchrotron-soleil.fr [Synchrotron SOLEIL, L´Orme des Merisiers, Saint-Aubin — BP 48 91192, Gif-sur-Yvette Cedex (France); Dawiec, A. [Synchrotron SOLEIL, L´Orme des Merisiers, Saint-Aubin — BP 48 91192, Gif-sur-Yvette Cedex (France); Graber-Bolis, J.; Arnaud, K. [CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille (France); Bérar, J.F.; Blanc, N.; Boudet, N. [Université Grenoble Alpes, Institut NÉEL, F-38042 Grenoble (France); CNRS, Institut NÉEL, F-38042 Grenoble (France); Clémens, J.C.; Debarbieux, F. [CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille (France); Delpierre, P.; Dinkespiler, B. [imXPAD SAS — Espace Mistral, Athélia IV, 297 avenue du Mistral, 13600 La Ciotat (France); Gastaldi, T. [CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille (France); Hustache, S. [Synchrotron SOLEIL, L´Orme des Merisiers, Saint-Aubin — BP 48 91192, Gif-sur-Yvette Cedex (France); Morel, C.; Pangaud, P. [CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille (France); Perez-Ponce, H. [imXPAD SAS — Espace Mistral, Athélia IV, 297 avenue du Mistral, 13600 La Ciotat (France); Vigeolas, E. [CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille (France)

    2014-09-11

    The CHIPSPECT consortium aims at building a large multi-modules CdTe based photon counting detector for hard X-ray applications. For this purpose, we tested nine XPAD3.2 single chip hybrids in various configurations (i.e. Ohmic vs. Schottky contacts or electrons vs. holes collection mode) in order to select the most performing and best suited configuration for our experimental requirements. Measurements have been done using both X-ray synchrotron beams and {sup 241}Am source. Preliminary results on the image quality, calibration, stability, homogeneity and linearity of the different types of detectors are presented.

  5. Runaway electron studies with hard x-ray and microwave diagnostics in the FT-2 lower hybrid current drive discharges

    Science.gov (United States)

    Shevelev, A. E.; Khilkevitch, E. M.; Lashkul, S. I.; Rozhdestvensky, V. V.; Pandya, S. P.; Plyusnin, V. V.; Altukhov, A. B.; Kouprienko, D. V.; Chugunov, I. N.; Doinikov, D. N.; Esipov, L. A.; Gin, D. B.; Iliasova, M. V.; Naidenov, V. O.; Polunovsky, I. A.; Sidorov, A. V.; Kiptily, V. G.

    2018-01-01

    Studies of the super-thermal and runaway electron behavior in ohmic and lower hybrid current drive FT-2 tokamak plasmas have been carried out using information obtained from measurements of hard x-ray spectra and non-thermal microwave radiation intensity at the frequency of 10 GHz and in the range of (53 ÷ 78) GHz. A gamma-ray spectrometer based on a scintillation detector with a LaBr3(Ce) crystal was used, which provides measurements at counting rates up to 107 s‑1. Reconstruction of the energy distribution of RE interacting with the poloidal limiter of the tokamak chamber was made with application of the DeGaSum code. Super-thermal electrons accelerated up to 2 MeV by the LH waves at the high-frequency pumping of the plasma with low density ≤ft ~ 2  ×  1013 cm‑3 and then up to 7 MeV by vortex electric field have been found. Experimental analysis of the runaway electron beam generation and evolution of their energy distribution in the FT-2 plasmas is presented in the article and compared with the numerical calculation of the maximum energy gained by runaway electrons for given plasma parameters. In addition, possible mechanisms for limiting the maximum energy gained by the runaway electrons are also calculated and described for a FT-2 plasma discharge.

  6. Development of Tiled Imaging CZT Detectors for Sensitive Wide-Field Hard X-Ray Surveys to EXIST

    Science.gov (United States)

    Grindlay, J.; Hong, J.; Allen, B.; Barthelmy, S.; Baker, R.

    2011-01-01

    Motivated by the proposed EXIST mission, a "medium-class" space observatory to survey black holes and the Early Universe proposed to the 2010 NAS/NRC Astronomy and Astrophysics Decadal Survey, we have developed the first "large" area 256 sq cm close-tiled (0.6 mm gaps) hard X-ray (20-600 keV) imaging detector employing pixelated (2.5 mm) CdZnTe (CZT) detectors, each 2 x 2 x 0.5 cubic cm. We summarize the design, development and operation of this detector array (8 x 8 CZTs) and its performance as the imager for a coded aperture telescope on a high altitude (40 km) balloon flight in October. 2009, as the ProtoEX1STl payload. We then outline our current development of a second-generation imager, ProtcEXIST2. with 0.6 mm pixels on a 32 x 32 array on each CZT, and how it will lead to the ultimate imaging system needed for EXIST. Other applications of this technology will also be mentioned.

  7. Simulation and experimental study of aspect ratio limitation in Fresnel zone plates for hard-x-ray optics.

    Science.gov (United States)

    Liu, Jianpeng; Shao, Jinhai; Zhang, Sichao; Ma, Yaqi; Taksatorn, Nit; Mao, Chengwen; Chen, Yifang; Deng, Biao; Xiao, Tiqiao

    2015-11-10

    For acquiring high-contrast and high-brightness images in hard-x-ray optics, Fresnel zone plates with high aspect ratios (zone height/zone width) have been constantly pursued. However, knowledge of aspect ratio limits remains limited. This work explores the achievable aspect ratio limit in polymethyl methacrylate (PMMA) by electron-beam lithography (EBL) under 100 keV, and investigates the lithographic factors for this limitation. Both Monte Carlo simulation and EBL on thick PMMA are applied to investigate the profile evolution with exposure doses over 100 nm wide dense zones. A high-resolution scanning electron microscope at low acceleration mode for charging free is applied to characterize the resultant zone profiles. It was discovered for what we believe is the first time that the primary electron-beam spreading in PMMA and the proximity effect due to extra exposure from neighboring areas could be the major causes of limiting the aspect ratio. Using the optimized lithography condition, a 100 nm zone plate with aspect ratio of 15/1 was fabricated and its focusing property was characterized at the Shanghai Synchrotron Radiation Facility. The aspect ratio limit found in this work should be extremely useful for guiding further technical development in nanofabrication of high-quality Fresnel zone plates.

  8. An accelerator scenario for a hard X-ray free electron laser combined with high energy electron radiography

    Science.gov (United States)

    Wei, Tao; Li, Yiding; Yang, Guojun; Pang, Jian; Li, Yuhui; Li, Peng; Pflueger, Joachim; He, Xiaozhong; Lu, Yaxin; Wang, Ke; Long, Jidong; Zhang, Linwen; Wu, Qiang

    2016-08-01

    In order to study the dynamic response of the material and the physical mechanism of fluid dynamics, an accelerator scenario which can be applied to both hard X-ray free electron laser and high energy electron radiography is proposed. This accelerator is mainly composed of a 12 GeV linac, an undulator branch and an eRad beamline. In order to characterize a sample’s dynamic behavior in situ and real-time with XFEL and eRad simultaneously, the linac should be capable of accelerating the two kinds of beam within the same operation mode. Combining in-vacuum and tapering techniques, the undulator branch can produce more than 1011 photons per pulse in 0.1% bandwidth at 42 keV. Finally, an eRad amplifying beamline with 1:10 ratio is proposed as an important complementary tool for the wider view field and density identification ability. Supported by China Academy of Engineering Physics (2014A0402016) and Institute of Fluid Physics (SFZ20140201)

  9. Evaluation of band offset at amorphous-Si/BaSi{sub 2} interfaces by hard x-ray photoelectron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Takabe, Ryota; Takeuchi, Hiroki; Du, Weijie; Toko, Kaoru; Suemasu, Takashi [Institute of Applied Physics, University of Tsukuba, Tsukuba, Ibaraki 305-8573 (Japan); Ito, Keita [Institute of Applied Physics, University of Tsukuba, Tsukuba, Ibaraki 305-8573 (Japan); Japan Society for the Promotion of Science (JSPS), Chiyoda, Tokyo 102-0083 (Japan); Department of Electronic Engineering, Graduate School of Engineering, Tohoku University, Sendai 980-8579 (Japan); Ueda, Shigenori [Synchrotron X-Ray Station at SPring-8, National Institute for Materials Science (NIMS), Sayo, Hyogo 679-5148 (Japan); Quantum Beam Unit, NIMS, Tsukuba, Ibaraki 305-0047 (Japan); Kimura, Akio [Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526 (Japan)

    2016-04-28

    The 730 nm-thick undoped BaSi{sub 2} films capped with 5 nm-thick amorphous Si (a-Si) intended for solar cell applications were grown on Si(111) by molecular beam epitaxy. The valence band (VB) offset at the interface between the BaSi{sub 2} and the a-Si was measured by hard x-ray photoelectron spectroscopy to understand the carrier transport properties by the determination of the band offset at this heterointerface. We performed the depth-analysis by varying the take-off angle of photoelectrons as 15°, 30°, and 90° with respect to the sample surface to obtain the VB spectra of the BaSi{sub 2} and the a-Si separately. It was found that the barrier height of the a-Si for holes in the BaSi{sub 2} is approximately −0.2 eV, whereas the barrier height for electrons is approximately 0.6 eV. This result means that the holes generated in the BaSi{sub 2} layer under solar radiation could be selectively extracted through the a-Si/BaSi{sub 2} interface, promoting the carrier separation in the BaSi{sub 2} layer. We therefore conclude that the a-Si/BaSi{sub 2} interface is beneficial for BaSi{sub 2} solar cells.

  10. Evaluation of the Fast-Electron Source Function for Two-Plasmon Decay from Temporal Hard X-Ray Emission

    Science.gov (United States)

    Delettrez, J. A.; Follett, R. K.; Myatt, J. F.; Stoeckl, C.

    2016-10-01

    The modeling of the fast-electron transport in the 1-D hydrodynamic code LILAC requires the description of the source electrons as a function of time. The particle-in-cell code OSIRIS and the interaction code FPSE provide some guidance but have not provided an algorithm for the energy fraction from the laser pulse as the coronal parameters change with time. The original algorithm, based on the measured hard x-ray (HXR) emission as a function of laser intensity, depended exponentially on the two-plasmon-decay threshold parameter up to about 0.9 and saturates above it. This algorithm along with FPSE simulations produced HXR emissions much earlier than observed. Analysis of the measured HXR emissions from implosions with near-constant threshold parameter values show that the rise time of the emission can be described with an exponential curve with roughly a rise time of 200 ps. Trial and error set the start of the rise at the threshold value of 0.75. Causes for this rise time will be discussed. Comparison between measured and computed HXR emissions for different implosion scenarios will be presented, including those for cryogenic targets. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

  11. A hard X-ray study of a manganese-terpyridine catalyst in a chromium-based Metal Organic Framework

    Energy Technology Data Exchange (ETDEWEB)

    Ramsey, Alexandra V. [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2015-08-28

    Hydrogen produced from water splitting is a promising source of clean energy. However, a robust catalyst is necessary to carry out the water oxidation step of water splitting. In this study, the catalyst studied was [(terpy)Mn(μ-O)2Mn(terpy)]3+ (MnTD) synthesized in the Metal Organic Framework (MOF) MIL-101(Cr), and the method used for analysis was hard X-ray powder diffraction. The diffraction data was used to detect the presence of MOF in different catalytic stages, and lattice parameters were assigned to the samples containing MOF. Fourier maps were constructed with GSAS II to determine the contents of the MOF as preliminary studies suggested that MnTD may not be present. Results showed that MOF is present before catalysis occurs but disappears by the time 45 minutes of catalysis has ensued. Changes in the MOF’s lattice parameters and location of electron density in the Fourier maps suggest attractions between the MOF and catalyst that may lead to MOF degradation. Fourier maps also revealed limited, if any, amounts of MnTD, even before catalysis occurred. Molecular manganese oxide may be the source of the high rate of water oxidation catalysis in the studied system.

  12. Development of tiled imaging CZT detectors for sensitive wide-field hard X-ray surveys to EXIST

    Science.gov (United States)

    Grindlay, J.; Hong, J.; Allen, B.; Barthelmy, S.; Baker, R.

    2011-10-01

    Motivated by the proposed EXIST mission, a "medium-class" space observatory to survey black holes and the Early Universe proposed to the 2010 NAS/NRC Astronomy and Astrophysics Decadal Survey, we have developed the first "large" area 256 cm 2 close-tiled (0.6 mm gaps) hard X-ray (20-600 keV) imaging detector employing pixelated (2.5 mm) CdZnTe (CZT) detectors, each 2×2×0.5 cm 3. We summarize the design, development and operation of this detector array (8×8 CZTs) and its performance as the imager for a coded aperture telescope on a high altitude (40 km) balloon flight in October, 2009, as the ProtoEXIST1 payload. We then outline our current development of a second-generation imager, ProtoEXIST2, with 0.6 mm pixels on a 32×32 array on each CZT, and how it will lead to the ultimate imaging system needed for EXIST. Other applications of this technology will also be mentioned.

  13. Center for X-Ray Optics, 1992

    Energy Technology Data Exchange (ETDEWEB)

    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.

  14. Design and throughput simulations of a hard x-ray split and delay line for the MID station at the European XFEL

    Energy Technology Data Exchange (ETDEWEB)

    Lu, W., E-mail: wei.lu@xfel.eu [Insitut für Optik und Atomare Physik, Technische Universität Berlin, 10623 Berlin (Germany); European X-Ray Free-Electron Laser Facility, 22607 Hamburg (Germany); Noll, T.; Eisebitt, S., E-mail: eisebitt@physik.tu-berlin.de [Insitut für Optik und Atomare Physik, Technische Universität Berlin, 10623 Berlin (Germany); Roth, T.; Agapov, I.; Geloni, G.; Hallmann, J.; Ansaldi, G.; Madsen, A., E-mail: anders.madsen@xfel.eu [European X-Ray Free-Electron Laser Facility, 22607 Hamburg (Germany); Holler, M. [Paul Scherrer Institut, 5232 Villigen – PSI (Switzerland)

    2016-07-27

    A hard X-ray Split and Delay Line (SDL) under development for the Materials Imaging and Dynamics (MID) station at the European X-Ray Free-Electron Laser (XFEL.EU) is presented. This device will provide pairs of X-ray pulses with a variable time delay ranging from −10 ps to 800 ps in a photon energy range from 5 to 10 keV. Throughput simulations in the SASE case indicate a total transmission of 1.1% or 3.5% depending on the operation mode. In the self-seeded case of XFEL.EU operation simulations indicate that the transmission can be improved to more than 11%.

  15. Element Specific Versus Integral Structural and Magnetic Properties of Co:ZnO and Gd:GaN Probed with Hard X-ray Absorption Spectroscopy

    Directory of Open Access Journals (Sweden)

    Andreas Ney

    2010-06-01

    Full Text Available Dilute magnetic semiconductors (DMS are envisioned as sources of spin-polarized carriers for future semiconductor devices which simultaneously utilize spin and charge of the carriers. The hope of discovering a DMS with ferromagnetic order up to room temperature still motivates research on suitable DMS materials. Two candidate wide-band gap DMS are Gd:GaN and Co:ZnO. We have used hard X-ray absorption spectroscopy (XAS and in particular X-ray linear dichroism (XLD and X-ray magnetic circular dichroism (XMCD to study both DMS materials with element specificity and compare these findings with results from integral SQUID magnetometry as well as electron paramagnetic resonance (EPR.

  16. On the Nature of the Hard X-Ray Sources SWIFT J1907.3-2050, IGR J12123-5802 and IGR J19552+0044

    Science.gov (United States)

    Bernardini, F.; deMartino, D; Mukai, K.; Falanga, M.; Andruchow, I.; Bonnet-Bidaud, J.-M.; Masetti, N.; GonzalezBuitrago, D. H.; Mouchet, M.; Tovmassian, G.

    2014-01-01

    The INTEGRAL and Swift hard X-ray surveys have identified a large number of new sources, among which many are proposed as Cataclysmic Variables (CVs). Here we present the first detailed study of three X-ray selected CVs, Swift J1907.3-2050, IGRJ12123-5802, and IGRJ19552+0044 based on XMM-Newton, Suzaku, Swift observations and ground based optical and archival nIR/IR data. Swift J1907.3-2050 is highly variable from hours to monthsyears at all wavelengths. No coherent X-ray pulses are detected but rather transient features. The X-ray spectrum reveals a multi-temperature optically thin plasma absorbed by complex neutral material and a soft black body component arising from a small area. These characteristics are remarkably similar to those observed in magnetic CVs. A supra-solar abundance of nitrogen could arise from nuclear processed material from the donor star. Swift J1907.3-2050 could be a peculiar magnetic CV with the second longest (20.82 h) binary period. IGRJ12123-5802 is variable in the X-rays on a timescale of approximately or greater than 7.6 h. No coherent pulsations are detected, but its spectral characteristics suggest that it could be a magnetic CV of the Intermediate Polar (IP) type. IGRJ19552+0044 shows two X-ray periods, approximately 1.38 h and approximately 1.69 h and a X-ray spectrum characterized by a multi-temperature plasma with little absorption.We derive a low accretion rate, consistent with a CV below the orbital period gap. Its peculiar nIR/IR spectrum suggests a contribution from cyclotron emission. It could either be a pre-polar or an IP with the lowest degree of asynchronism.

  17. Conceptual design of the tomographic system for simultaneous studying of soft and hard X-ray emission from dense magnetized plasma

    Energy Technology Data Exchange (ETDEWEB)

    Bielecki, J., E-mail: jakub.bielecki@ifj.edu.edu; Wójcik-Gargula, A.; Scholz, M.

    2016-11-15

    The article presents a new approach for investigation of spatial distributions of soft and hard X-rays emitted from dense magnetized plasma. The approach is based on the application of tomographic methods to the X-ray emission reconstruction in a plasma focus (PF) device. Quantitative investigation of the anisotropy of the reconstructed X–ray plasma emissivity may help to explain the nature of fusion reaction mechanisms in a PF device. The aim of this work is to present a conceptual design of a novel dual-energy X-ray emission tomographic system dedicated to the PF-24 plasma focus device. The system, which enables the simultaneous registration of soft and hard X-rays, is composed of three X‐ray pinhole cameras. Each camera is equipped with a pair of 16-element Si photodiode arrays arranged in two layers separated by an aluminum attenuator. The Geant4 code was used to optimize the layout and parameters of the applied detectors. In addition, a method of tomographic reconstruction from a sparse data set provided by the experimental setup has been presented.

  18. Space Vehicle Prompt X-Ray Hardness Design and Test Protocol. Volume 2. Appendices D Through K

    National Research Council Canada - National Science Library

    Keyser, Robert

    2004-01-01

    .... The prompt x-ray hardening and validation processes are described in flow charts in the protocols, which show the key decision points in the processes, and verification matrices to assure completion of the process...

  19. Caliste 64: detection unit of a spectro imager array for a hard x-ray space telescope

    Science.gov (United States)

    Limousin, O.; Meuris, A.; Lugiez, F.; Gevin, Olivier; Pinsard, F.; Blondel, C.; Le Mer, I.; Delagnes, E.; Vassal, M. C.; Soufflet, F.; Bocage, R.; Penquer, A.; Billot, M.

    2017-11-01

    In the frame of the hard X-ray Simbol-X observatory, a joint CNES-ASI space mission to be flown in 2014, a prototype of miniature Cd(Zn)Te camera equipped with 64 pixels has been designed. The device, called Caliste 64, is a spectro-imager with high resolution event timetagging capability. Caliste 64 integrates a Cd(Zn)Te semiconductor detector with segmented electrode and its front-end electronics made of 64 independent analog readout channels. This 1 × 1 × 2 cm3 camera, able to detect photons in the range from 2 keV up to 250 keV, is an elementary detection unit juxtaposable on its four sides. Consequently, large detector array can be made assembling a mosaic of Caliste 64 units. Electronics readout module is achieved by stacking four IDeF-X V1.1 ASICs, perpendicular to the detection plane. We achieved good noise performances, with a mean Equivalent Noise Charge of 65 electrons rms over the 64 channels. For the first prototypes, we chose Pt//CdTe//Al/Ti/Au Schottky detectors because of their very low dark current and excellent spectroscopic performances. Recently a Caliste 64 prototype has been also equipped with a 2 mm thick Au//CdZnTe//Au detector. This paper presents the performances of these four prototypes and demonstrates spectral performances better than 1 keV fwhm at 59.54 keV when the samples are moderately cooled down to -10°C.

  20. A comparison of the thick-target model with stereo data on the height structure of solar hard X-ray bursts

    Science.gov (United States)

    Brown, J. C.; Carlaw, V. A.; Cromwell, D.; Kane, S. R.

    1983-01-01

    The thick target, hard solar X-ray source height structure is predicted for the case of a beam that is injected vertically downward, having a power law spectrum, being dominated by Coulomb collisional energy losses, and being structurally characterized by the ratio of hard X-ray flux from an upper part of the source to that from the entire source. These predictions are compared with the flux ratios at 150 and 350 keV which were observed by two spacecraft for five events in which the solar limb occults part of the source for one spacecraft. The energy dependence of the occultation ratio is found to be inconsistent with that predicted by the model, and it is concluded that noncollisional losses must be significant in beam dynamics.

  1. Monte-Carlo simulation of noise in hard X-ray Transmission Crystal Spectrometers: Identification of contributors to the background noise and shielding optimizationa)

    Science.gov (United States)

    Thfoin, I.; Reverdin, C.; Hulin, S.; Szabo, C. I.; Bastiani-Ceccotti, S.; Batani, D.; Brambrink, E.; Koenig, M.; Duval, A.; Leboeuf, X.; Lecherbourg, L.; Rossé, B.; Morace, A.; Santos, J. J.; Vaisseau, X.; Fourment, C.; Giuffrida, L.; Nakatsutsumi, M.

    2014-11-01

    Transmission crystal spectrometers (TCS) are used on many laser facilities to record hard X-ray spectra. During experiments, signal recorded on imaging plates is often degraded by a background noise. Monte-Carlo simulations made with the code GEANT4 show that this background noise is mainly generated by diffusion of MeV electrons and very hard X-rays. An experiment, carried out at LULI2000, confirmed that the use of magnets in front of the diagnostic, that bent the electron trajectories, reduces significantly this background. The new spectrometer SPECTIX (Spectromètre PETAL à Cristal en TransmIssion X), built for the LMJ/PETAL facility, will include this optimized shielding.

  2. Monte-Carlo simulation of noise in hard X-ray Transmission Crystal Spectrometers: identification of contributors to the background noise and shielding optimization.

    Science.gov (United States)

    Thfoin, I; Reverdin, C; Hulin, S; Szabo, C I; Bastiani-Ceccotti, S; Batani, D; Brambrink, E; Koenig, M; Duval, A; Leboeuf, X; Lecherbourg, L; Rossé, B; Morace, A; Santos, J J; Vaisseau, X; Fourment, C; Giuffrida, L; Nakatsutsumi, M

    2014-11-01

    Transmission crystal spectrometers (TCS) are used on many laser facilities to record hard X-ray spectra. During experiments, signal recorded on imaging plates is often degraded by a background noise. Monte-Carlo simulations made with the code GEANT4 show that this background noise is mainly generated by diffusion of MeV electrons and very hard X-rays. An experiment, carried out at LULI2000, confirmed that the use of magnets in front of the diagnostic, that bent the electron trajectories, reduces significantly this background. The new spectrometer SPECTIX (Spectromètre PETAL à Cristal en TransmIssion X), built for the LMJ/PETAL facility, will include this optimized shielding.

  3. Monte-Carlo simulation of noise in hard X-ray Transmission Crystal Spectrometers: Identification of contributors to the background noise and shielding optimization

    Energy Technology Data Exchange (ETDEWEB)

    Thfoin, I., E-mail: isabelle.lantuejoul@cea.fr; Reverdin, C.; Duval, A.; Leboeuf, X.; Lecherbourg, L.; Rossé, B. [CEA, Centre de Saclay, IRFU, F-91191 Gif-sur-Yvette (France); Hulin, S.; Batani, D.; Santos, J. J.; Vaisseau, X.; Fourment, C.; Giuffrida, L. [CELIA, Université de Bordeaux-CNRS-CEA, F-33405 Talence (France); Szabo, C. I. [Laboratoire Kastler Brossel, ENS, CNRS, UPMC, 75005 Paris Cedex (France); Bastiani-Ceccotti, S.; Brambrink, E.; Koenig, M.; Nakatsutsumi, M. [LULI Ecole Polytechnique, CNRS, CEA, UPMC, 91128 Palaiseau (France); Morace, A. [University of Milano, via Celoria 16, 20133 Milano (Italy)

    2014-11-15

    Transmission crystal spectrometers (TCS) are used on many laser facilities to record hard X-ray spectra. During experiments, signal recorded on imaging plates is often degraded by a background noise. Monte-Carlo simulations made with the code GEANT4 show that this background noise is mainly generated by diffusion of MeV electrons and very hard X-rays. An experiment, carried out at LULI2000, confirmed that the use of magnets in front of the diagnostic, that bent the electron trajectories, reduces significantly this background. The new spectrometer SPECTIX (Spectromètre PETAL à Cristal en TransmIssion X), built for the LMJ/PETAL facility, will include this optimized shielding.

  4. Hard x-ray (>100 keV) imager to measure hot electron preheat for indirectly driven capsule implosions on the NIF.

    Science.gov (United States)

    Döppner, T; Dewald, E L; Divol, L; Thomas, C A; Burns, S; Celliers, P M; Izumi, N; Kline, J L; LaCaille, G; McNaney, J M; Prasad, R R; Robey, H F; Glenzer, S H; Landen, O L

    2012-10-01

    We have fielded a hard x-ray (>100 keV) imager with high aspect ratio pinholes to measure the spatially resolved bremsstrahlung emission from energetic electrons slowing in a plastic ablator shell during indirectly driven implosions at the National Ignition Facility. These electrons are generated in laser plasma interactions and are a source of preheat to the deuterium-tritium fuel. First measurements show that hot electron preheat does not limit obtaining the fuel areal densities required for ignition and burn.

  5. Bright end of the luminosity function of high-mass X-ray binaries: contributions of hard, soft and supersoft sources

    Science.gov (United States)

    Sazonov, S.; Khabibullin, I.

    2017-04-01

    Using a spectral analysis of bright Chandra X-ray sources located in 27 nearby galaxies and maps of star-formation rate (SFR) and interstellar medium surface densities for these galaxies, we constructed the intrinsic X-ray luminosity function (XLF) of luminous high-mass X-ray binaries (HMXBs), taking into account absorption effects and the diversity of HMXB spectra. The XLF per unit SFR can be described by a power-law dN/dlog LX,unabs ≈ 2.0(LX,unabs/1039 erg s-1)-0.6 (M⊙ yr-1)-1 from LX,unabs = 1038 to 1040.5 erg s-1, where LX,unabs is the unabsorbed luminosity at 0.25-8 keV. The intrinsic number of luminous HMXBs per unit SFR is a factor of ˜2.3 larger than the observed number reported before. The intrinsic XLF is composed of hard, soft and supersoft sources (defined here as those with the 0.25-2 keV to 0.25-8 keV flux ratio of 0.95, respectively) in ˜ 2:1:1 proportion. We also constructed the intrinsic HMXB XLF in the soft X-ray band (0.25-2 keV). Here, the numbers of hard, soft and supersoft sources prove to be nearly equal. The cumulative present-day 0.25-2 keV emissivity of HMXBs with luminosities between 1038 and 1040.5 erg s-1 is ˜5 × 1039 erg s-1(M⊙ yr-1)-1, which may be relevant for studying the X-ray preheating of the early Universe.

  6. Room temperature redox reaction by oxide ion migration at carbon/Gd-doped CeO2 heterointerface probed by an in situ hard x-ray photoemission and soft x-ray absorption spectroscopies

    Directory of Open Access Journals (Sweden)

    Takashi Tsuchiya, Shogo Miyoshi, Yoshiyuki Yamashita, Hideki Yoshikawa, Kazuya Terabe, Keisuke Kobayashi and Shu Yamaguchi

    2013-01-01

    Full Text Available In situ hard x-ray photoemission spectroscopy (HX-PES and soft x-ray absorption spectroscopy (SX-XAS have been employed to investigate a local redox reaction at the carbon/Gd-doped CeO2 (GDC thin film heterointerface under applied dc bias. In HX-PES, Ce3d and O1s core levels show a parallel chemical shift as large as 3.2 eV, corresponding to the redox window where ionic conductivity is predominant. The window width is equal to the energy gap between donor and acceptor levels of the GDC electrolyte. The Ce M-edge SX-XAS spectra also show a considerable increase of Ce3+ satellite peak intensity, corresponding to electrochemical reduction by oxide ion migration. In addition to the reversible redox reaction, two distinct phenomena by the electrochemical transport of oxide ions are observed as an irreversible reduction of the entire oxide film by O2 evolution from the GDC film to the gas phase, as well as a vigorous precipitation of oxygen gas at the bottom electrode to lift off the GDC film. These in situ spectroscopic observations describe well the electrochemical polarization behavior of a metal/GDC/metal capacitor-like two-electrode cell at room temperature.

  7. Hard x-ray Morphological and Spectral Studies of the Galactic Center Molecular Cloud SGR B2: Constraining Past SGR A* Flaring Activity

    DEFF Research Database (Denmark)

    Zhang, Shuo; Hailey, Charles J.; Mori, Kaya

    2015-01-01

    In 2013, NuSTAR observed the Sgr B2 region and for the first time resolved its hard X-ray emission on subarcminute scales. Two prominent features are detected above 10 keV:. a newly emerging cloud, G0.66-0.13, and the central 90 '' radius region containing two compact cores, Sgr B2(M) and Sgr B2(N......), surrounded by diffuse emission. It is inconclusive whether the remaining level of Sgr. B2 emission is still decreasing or has reached a constant background level. A decreasing X-ray emission can be best explained by the X-ray reflection nebula scenario, where the cloud reprocesses a past giant outburst from...... Sgr A*. In the X-ray reflection nebula (XRN) scenario, the 3-79 keV Sgr. B2 spectrum allows us to self-consistently test the XRN model using both the Fe K alpha line and the continuum emission. The peak luminosity of the past Sgr A* outburst is constrained to L3-79keV∼5 x 1038 ergs s-1. A newly...

  8. Growth, structure, and performance of depth-graded W/Si multilayers for hard x-ray optics

    DEFF Research Database (Denmark)

    Windt, D.L.; Christensen, Finn Erland; Craig, W.W.

    2000-01-01

    -graded W/Si multilayer structures, and high-resolution transmission electron microscopy (TEM) and selected area electron diffraction (SAED) to characterize the interface structure and layer morphology as a function of depth in an optimized depth-graded multilayer. From x-ray analysis we find interface......), and somewhat larger interface widths (i.e., sigma=0.35-0.4 nm) for structures grown at higher Ar pressures, higher background pressures, or with larger target-to-substrate distances. We find no variation in interface widths with magnetron power. Nonspecular x-ray reflectance analysis and TEM suggest......, or with a depth-graded distribution of interface widths in the range sigma=0.275-0.35 nm (as suggested by 8 keV x-ray and TEM analyses) for a structure containing 150 bilayers, and designed for high reflectance over the range 20 keV structure good agreement between reflectance...

  9. NuSTAR study of hard X-ray morphology and spectroscopy of PWN G21.5-0.9

    DEFF Research Database (Denmark)

    Nynka, Melania; Hailey, Charles J.; Reynolds, Stephen P.

    2014-01-01

    STAR agrees well with that seen by XMM-Newton and Chandra below 10 keV. At high energies, NuSTAR clearly detects non-thermal emission up to similar to 20 keV that extends along the eastern and northern rim of the supernova shell. The broadband images clearly demonstrate that X-ray emission from the North Spur...... & Coroniti. This value, along with the observed steepening in power-law index between radio and X-ray, can be quantitatively explained as an energy-loss spectral break in the simple scaling model of Reynolds, assuming particle advection dominates over diffusion. This interpretation requires a substantial...

  10. The Bionanoprobe: Synchrotron-Based Hard X-ray Fluorescence Microscopy for 2D/3D Trace Element Mapping

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Si; Paunesku, Tatjana; Yuan, Ye; Jin, Qiaoling; Finney, Lydia; Hornberger, Benjamin; Flachenecker, Claus; Lai, Barry; Brister, Keith; Jacobsen, Chris; Woloschak, Gayle; Vogt, Stefan

    2015-04-29

    Trace elements, particularly metals, play an important role in a large variety of cellular processes in a biological system. In the context of biological organisms and tissues, the term trace element means that over the entire organisms an element is present at only trace levels, 100ppm or lower. Trace element distribution and content can be analyzed using several techniques, for example, visible light optical fluorescence imaging, energy-dispersive X-ray spectroscopy on an election microscope, synchrotron-based X-ray fluorescence (XRF) imagine,

  11. Extreme-ultraviolet and hard X-ray signatures of electron acceleration during the failed eruption of a filament

    Science.gov (United States)

    Netzel, A.; Mrozek, T.; Kołomański, S.; Gburek, S.

    2012-12-01

    Aims: We search for extreme-ultraviolet (EUV) brightenings in TRACE 171 Å images and hard X-ray (HXR) bursts observed during failed eruptions. We expect that if an eruption is confined by interaction with overlaying magnetic structures, we should observe effects caused by reconnection between magnetic structures and acceleration of particles. Methods: We used TRACE observations of three well-observed failed eruptions. A semi-automated method was used to search for abrupt brightness changes in the TRACE field of view. The EUV images were compared to the HXR spatial distribution reconstructed from YOHKOH/HXT and RHESSI data. The EUV light curves of a selected area were compared to height profiles of eruption, HXR emission, and the HXR photon spectral index of a power-law fit to the HXR data. Results: We have found that EUV brightenings are closely relatedto the eruption velocity decrease, to HXR bursts, and to episodes of hardening of the HXR spectra. The EUV-brightened areas are observed far from the flaring structure, in footpoints of large systems of loops observed 30-60 min after the maximum of a flare. These are not "post-flare" loops, which are also observed, but at significantly lower heights. The high-lying systems of loops are observed at heights equal to the height at which the eruption was observed to stop. We observed only one HXR source that was spatially correlated with EUV brightening. For other EUV-brightened areas we estimated the expected brightness of HXR sources. Conclusions: We find that EUV brightenings are produced by interaction between the erupting structure with overlaying loops. The interaction is strong enough to heat the system of high loops. These loops cool and are visible in the EUV range about 30-60 min later. The estimated brightness of HXR sources associated with EUV brightenings shows that they are too weak to be detected with present instruments. However, next-generation instruments will have sufficient dynamic range and

  12. On the features of bursts of neutrons, hard x-rays and alpha-particles in the pulse vacuum discharge with a virtual cathode and self-organization

    Science.gov (United States)

    Kurilenkov, Yu K.; Tarakanov, V. P.; Gus'kov, S. Yu; Samoylov, I. S.; Ostashev, V. E.

    2015-11-01

    In this paper, we continue the discussion of the experimental results on the yield of DD neutrons and hard x-rays in the nanosecond vacuum discharge (NVD) with a virtual cathode, which was started in the previous article of this issue, and previously (Kurilenkov Y K et al 2006 J. Phys. A: Math. Gen. 39 4375). We have considered here the regimes of very dense interelectrode aerosol ensembles, in which diffusion of even hard x-rays is found. The yield of DD neutrons in these regimes is conditioned not only by the head-on deuteron-deuteron collisions in the potential well of virtual cathode, but also by the channel of “deuteron-deuterium cluster” reaction, which exceeds overall yield of neutrons per a shot by more than an order of magnitude, bringing it up to ∼ 107/(4π). Very bright bursts of hard x-rays are also represented and discussed here. Presumably, their nature may be associated with the appearance in the NVD of some properties of random laser in the x-ray spectrum. Good preceding agreeing of the experiment on the DD fusion in the NVD with its particle-in-cell (PIC) simulations provides a basis to begin consideration of nuclear burning “proton-boron” in the NVD, which will be accompanied by the release of alpha particles only. With this objective in view, there has been started the PIC-simulation of aneutronic burning of p-B11, and its preliminary results are presented.

  13. NuSTAR Study of Hard X-ray Morphology and Spectroscopy G21.5-0.9

    Science.gov (United States)

    Nynka, Melania; Hailey, Charles J.; Reynolds, Stephen P.; An, Hongjun; Baganoff, Frederick K.; Boggs, Steven E.; Christensen, Finn E.; Craig, William W.; Gotthelf, Eric V.; Grefenstette, Brian W.; hide

    2014-01-01

    We present NuSTAR high-energy X-ray observations of the pulsar wind nebula (PWN)/supernova remnant G21.5-0.9. We detect integrated emission from the nebula up to approx. 40 keV, and resolve individual spatial features over a broad X-ray band for the first time. The morphology seen by NuSTAR agrees well with that seen by XMM-Newton and Chandra below 10 keV. At high energies, NuSTAR clearly detects non-thermal emission up to approx. 20 keV that extends along the eastern and northern rim of the supernova shell. The broadband images clearly demonstrate that X-ray emission from the North Spur and Eastern Limb results predominantly from non-thermal processes. We detect a break in the spatially integrated X-ray spectrum at approx. 9 keV that cannot be reproduced by current spectral energy distribution models, implying either a more complex electron injection spectrum or an additional process such as diffusion compared to what has been considered in previous work. We use spatially resolved maps to derive an energy-dependent cooling length scale, E(sup m) is directly proportional to L(E) with m = -0.21 plus or minus 0.01. We find this to be inconsistent with the model for the morphological evolution with energy described by Kennel & Coroniti. This value, along with the observed steepening in power-law index between radio and X-ray, can be quantitatively explained as an energy-loss spectral break in the simple scaling model of Reynolds, assuming particle advection dominates over diffusion. This interpretation requires a substantial departure from spherical magnetohydrodynamic, magnetic-flux-conserving outflow, most plausibly in the form of turbulent magnetic-field amplification.

  14. Revealing a hard X-ray spectral component that reverberates within one light hour of the central supermassive black hole in Ark 564

    Science.gov (United States)

    Giustini, M.; Turner, T. J.; Reeves, J. N.; Miller, L.; Legg, E.; Kraemer, S. B.; George, I. M.

    2015-05-01

    Context. Arakelian 564 (Ark 564, z = 0.0247) is an X-ray-bright narrow-line Seyfert 1 galaxy. By using advanced X-ray timing techniques, an excess of "delayed" emission in the hard X-ray band (4-7.5 keV) following about 1000 s after "flaring" light in the soft X-ray band (0.4 - 1 keV) was recently detected. Aims: We report on the X-ray spectral analysis of eight XMM-Newton and one Suzaku observation of Ark 564. Our aim is to characterise the X-ray spectral properties of the source in the light of these recently reported results. Methods: High-resolution spectroscopy was performed with the RGS in the soft X-ray band, while broad-band spectroscopy was performed with the EPIC-pn and XIS/PIN instruments. We analysed time-averaged, flux-selected, and time-resolved spectra. Results: Despite the strong variability in flux during our observational campaign, the broad-band spectral shape of Ark 564 does not vary dramatically and can be reproduced either by a superposition of a power law and a blackbody emission or by a Comptonized power-law emission model. High-resolution spectroscopy revealed ionised gas along the line of sight at the systemic redshift of the source, with a low column density (NH ~ 1021 cm-2) and a range of ionisation states (-0.8 3.5. A reflection-dominated or an absorption-dominated model are similarly able to well reproduce the time-averaged data from a statistical point of view, in both cases requiring contrived geometries and/or unlikely physical parameters. Finally, through time-resolved analysis we spectroscopically identified the "delayed" emission as a spectral hardening above ~4 keV; the most likely interpretation for this component is a reprocessing of the "flaring" light by gas located at 10-100 rg from the central supermassive black hole that is so hot that it can Compton-upscatter the flaring intrinsic continuum emission.

  15. The condensation of the corona for the correlation between the hard X-ray photon index Γ and the reflection scaling factor ℜ in active galactic nuclei

    Science.gov (United States)

    Qiao, Erlin; Liu, B. F.

    2017-05-01

    Observationally, it is found that there is a strong correlation between the hard X-ray photon index Γ and the Compton reflection scaling factor ℜ in active galactic nuclei. In this paper, we propose that the Γ - ℜ correlation can be explained within the framework of the condensation of the hot corona on to the cold accretion disc around a supermassive black hole. In the model, it is presumed that, initially, a vertically extended hot gas (corona) is supplied to the central supermassive black hole by capturing the interstellar medium and stellar wind. In this scenario, when the initial mass accretion rate \\dot{M}/ \\dot{M}_Edd ≳ 0.01, at a critical radius rd, part of the hot gas begins to condense on to the equatorial disc plane of the black hole, forming an inner cold accretion disc. Then, the matter is accreted in the form of a disc-corona structure extending down to the innermost stable circular orbits of the black hole. The size of the inner disc is determined by the initial mass accretion rate. With the increase of the initial mass accretion rate, the size of the inner disc increases, which results in both the increase of the Compton reflection scaling factor ℜ and the increase of the hard X-ray photon index Γ. By comparing with a sample of Seyfert galaxies with well-fitted X-ray spectra, it is found that our model can roughly explain the observations. Finally, we discuss the possibility of applying our model to high-mass X-ray binaries, which are believed to be fuelled by hot winds from the companion stars.

  16. The very faint hard state of the persistent neutron star X-ray binary SLX 1737-282 near the Galactic Centre

    Science.gov (United States)

    Armas Padilla, M.; Ponti, G.; De Marco, B.; Muñoz-Darias, T.; Haberl, F.

    2018-01-01

    We report on a detailed study of the spectral and temporal properties of the neutron star low-mass X-ray binary SLX 1737-282, which is located only ∼1° away from Sgr A*. The system is expected to have a short orbital period, even within the ultracompact regime, given its persistent nature at low X-ray luminosities and the long duration thermonuclear burst that it has displayed. We have analysed a Suzaku (18 ks) observation and an XMM-Newton (39 ks) observation taken 7 yr apart. We infer (0.5-10 keV) X-ray luminosities in the range of 3-6 × 1035ergs-1, in agreement with previous findings. The spectra are well described by a relatively cool (kTbb = 0.5 keV) blackbody component plus a Comptonized emission component with Γ ∼ 1.5-1.7. These values are consistent with the source being in a faint hard state, as confirmed by the ∼20 per cent fractional root-mean-square amplitude of the fast variability (0.1-7 Hz) inferred from the XMM-Newton data. The electron temperature of the corona is ≳7 keV for the Suzaku observation, but it is measured to be as low as ∼2 keV in the XMM-Newton data at higher flux. The latter is significantly lower than expected for systems in the hard state. We searched for X-ray pulsations and imposed an upper limit to their semi-amplitude of 2 per cent (0.001-7 Hz). Finally, we investigated the origin of the low-frequency variability emission present in the XMM-Newton data and ruled out an absorption dip origin. This constraint the orbital inclination of the system to ≲65° unless the orbital period is longer than 11 h (i.e. the length of the XMM-Newton observation).

  17. INTEGRAL/IBIS detection of hard X-ray activity from the HMXB 4U 1036-56

    DEFF Research Database (Denmark)

    Sguera, V.; Bazzano, A.; Fiocchi, M.

    2015-01-01

    The Be high mass X-ray binary (HMXB) 4U 1036-56 has been recently detected by INTEGRAL/JEM-X during enhanced activity in the soft X-ray band 3-10 KeV (ATel #8425). On the contrary no emission was detected by INTEGRAL/IBIS in the band 22-60 keV, leading to a 3sigma upper limit of 6 mCrab. INTEGRAL...... was never in the field of view of JEM-X monitor during this observation. The IBIS/ISGRI spectrum is reasonably fitted by a power law with photon index 2.3+/-0.8. The average flux is 1.8 x 10-10 erg cm-2 s-1 (18-60 keV) which, at the 5 kpc source distance, translates into a luminosity of 5.4 x 1035 erg s-1....

  18. Experimental study for the feasibility of using hard x-rays for micro-XRF analysis of multilayered metals

    Directory of Open Access Journals (Sweden)

    C. Polese

    2014-07-01

    Full Text Available Application of polycapillary optical systems to improve a spatial resolution for the μ-XRF analysis by focusing a primary x-ray beam and/or by collecting fluorescence emission is well known. The challenge is to optimize them in combination with x-ray source for exciting K-lines above 20 keV that could allow characterization of many materials composed by heavy elements. To pursue this goal, preliminary studies on possible polycapillary lens employment in thickness determination for multilayer metal materials will be presented in this work. In this paper, the results of first attempts of integrating PyMCA with Monte Carlo simulation code (XMI-MSIM that takes into account the secondary fluorescence effects on quantitative analysis of homogeneous matrices, in particular, metal alloys, are presented.

  19. NuSTAR Hard X-Ray Observation of the Gamma-Ray Binary Candidate HESS J1832–093

    DEFF Research Database (Denmark)

    Mori, Kaya; Gotthelf, E. V.; Hailey, Charles J.

    2017-01-01

    −093, is detected up to ~30 keV and is well-described by an absorbed power-law model with a best-fit photon index . A re-analysis of archival Chandra and XMM-Newton data finds that the long-term X-ray flux increase of XMMU J183245−0921539 is (90% C.L.), much less than previously reported. A search for a pulsar spin...

  20. INTEGRAL hard X-ray detection of HMXB GX 304-1 and H1417-624

    DEFF Research Database (Denmark)

    Manousakis, A.; Beckmann, V.; Bianchin, V.

    2008-01-01

    We report on the first detection of the Be star HMXBs GX 304-1 and H1417-624 above 20 keV with the IBIS/ISGRI X-ray imager on board INTEGRAL. From 2008-06-24 to 2008-07-09, INTEGRAL performed monitoring observations of the Galactic plane around l=305 degrees for a total exposure time of 352 ksec....

  1. A beam branching method for timing and spectral characterization of hard X-ray free-electron lasers

    Directory of Open Access Journals (Sweden)

    Tetsuo Katayama

    2016-05-01

    Full Text Available We report a method for achieving advanced photon diagnostics of x-ray free-electron lasers (XFELs under a quasi-noninvasive condition by using a beam-splitting scheme. Here, we used a transmission grating to generate multiple branches of x-ray beams. One of the two primary diffracted branches (+1st-order is utilized for spectral measurement in a dispersive scheme, while the other (−1st-order is dedicated for arrival timing diagnostics between the XFEL and the optical laser pulses. The transmitted x-ray beam (0th-order is guided to an experimental station. To confirm the validity of this timing-monitoring scheme, we measured the correlation between the arrival timings of the −1st and 0th branches. The observed error was as small as 7.0 fs in root-mean-square. Our result showed the applicability of the beam branching scheme to advanced photon diagnostics, which will further enhance experimental capabilities of XFEL.

  2. Detection of Hard X-Rays in Air for Precise Monitoring of Vertical Position & Emittance in the ESRF Dipoles

    CERN Document Server

    Scheidt, B K

    2005-01-01

    The un-used X-rays produced in each of the 64 ESRF dipoles are absorbed in so-called crotch absorbers at the end of the dipole. With 40mm of Copper + 5mm of Steel only 250uW/mrad (out of the total emitted power fan of 154W/mrad) traverse the absorber. About 20% of these >170 keV energy X-rays are converted by a 0.5mm thick high-Z CadmiumTungstenate (CdWO4) scintilator into visible light that is collected and focussed by simple optics on to a commercial CCD camera. This compact monitor operates in air and is situated just behind the crotch chamber. The knowledge of the small vertical opening angle of 170 keV X-rays and the distance of the source-point to the scintillator makes it possible to calculate precisely the vertical electron beamsize at this sourcepoint. The light yield is enough to measure at 1 kHz frequency, with a sub-micron meter precision of the beam position, thereby also constituting a powerful tool for beam stability measurement in the vertical plane. The principle, the practical realisation an...

  3. Transition of an X-ray binary to the hard ultraluminous state in the blue compact dwarf galaxy VII Zw 403

    Science.gov (United States)

    Brorby, M.; Kaaret, P.; Feng, H.

    2015-04-01

    We examine the X-ray spectra of VII Zw 403, a nearby low-metallicity blue compact dwarf (BCD) galaxy. The galaxy has been observed to contain an X-ray source, likely a high-mass X-ray binary (HMXB), with a luminosity of 1.3-23 × 1038 erg s-1 in the 0.3-8 keV energy range. A new Suzaku observation shows a transition to a luminosity of 1.7 × 1040 erg s-1 [0.3-8 keV], higher by a factor of 7-130. The spectra from the high-flux state are hard, best described by a disc plus Comptonization model, and exhibit curvature at energies above 5 keV. This is consistent with many high-quality ultraluminous X-ray source spectra which have been interpreted as stellar mass black holes accreting at super-Eddington rates. However, this lies in contrast to another HMXB in a low-metallicity BCD, I Zw 18, that exhibits a soft spectrum at high flux, similar to Galactic black hole binaries and has been interpreted as a possible intermediate-mass black hole. Determining the spectral properties of HMXBs in BCDs has important implications for models of the Epoch of Reionization. It is thought that the main component of X-ray heating in the early Universe was dominated by HMXBs within the first galaxies. Early galaxies were small, metal-deficient, star-forming galaxies with large H I mass fractions - properties shared by local BCDs we see today. Understanding the spectral evolution of HMXBs in early Universe analogue galaxies, such as BCDs, is an important step in estimating their contribution to the heating of the intergalactic medium during the Epoch of Reionization. The strong contrast between the properties of the only two spectroscopically studied HMXBs within BCDs motivates further study on larger samples of HMXBs in low-metallicity environments in order to properly estimate the X-ray heating in the early Universe.

  4. A novel hohlraum with ultrathin depleted-uranium-nitride coating layer for low hard x-ray emission and high radiation temperature

    CERN Document Server

    Guo, Liang; Xing, Peifeng; Li, Sanwei; Yi, Taimin; Kuang, Longyu; Li, Zhichao; Li, Renguo; Wu, Zheqing; Jing, Longfei; Zhang, Wenhai; Zhan, Xiayu; Yang, Dong; Jiang, Bobi; Yang, Jiamin; Liu, Shenye; Jiang, Shaoen; Li, Yongsheng; Liu, Jie; Huo, Wenyi; Lan, Ke

    2014-01-01

    An ultra-thin layer of uranium nitrides (UN) has been coated on the inner surface of the depleted uranium hohlraum (DUH), which has been proved by our experiment can prevent the oxidization of Uranium (U) effectively. Comparative experiments between the novel depleted uranium hohlraum and pure golden (Au) hohlraum are implemented on Shenguang III prototype laser facility. Under the laser intensity of 6*10^14 W/cm2, we observe that, the hard x-ray (> 1.8 keV) fraction of this uranium hohlraum decreases by 61% and the peak intensity of total x-ray flux (0.1 keV ~ 5 keV) increases by 5%. Two dimensional radiation hydrodynamic code LARED are exploited to interpret the above observations. Our result for the first time indicates the advantage of the UN-coated DUH in generating the uniform x-ray field with a quasi Planckian spectrum and thus has important implications in optimizing the ignition hohlraum design.

  5. Coordinated NuSTAR and Swift observations of SU Lyncis: a hard X-ray bright symbiotic star with weak optical signatures

    Science.gov (United States)

    Lopes de Oliveira, Raimundo; Mukai, Koji; Luna, Gerardo Juan Manuel; Sokoloski, Jennifer; Nelson, Thomas; Lucy, Adrian B.

    2018-01-01

    The variable M giant SU Lyncis was recently identified as the optical counterpart of a hard, thermal X-ray source. Also considering the fact that the star displays weak high-excitation emission, it was classified as a symbiotic system purely powered by accretion without accompanying nuclear fusion. This discovery revealed the existence of a subclass of symbiotics which is "invisible" to optical surveys and thus underestimated since these surveys favour the identification of systems with more intense emission lines that arise when shell-burning is present. At the same time, this discovery opens up a new window to investigate accretion and evolution of symbiotic systems. Here we report on the X-ray and UV properties of SU Lyncis derived from simultaneous NuSTAR and Swift observations. The investigation is focused on the strong photometric variability in UV and on the X-ray spectral characterization, which is associated with a hot thermal plasma with sub-solar abundance and suffering the effects of a relatively dense local absorber. The results are discussed in the context of the accretion geometry and mass of the white dwarf, and the imposed limits to the reflection fraction.

  6. A simple method to prevent hard X-ray-induced preheating effects inside the cone tip in indirect-drive fast ignition implosions

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Dongxiao; Shan, Lianqiang; Zhou, Weimin; Wu, Yuchi; Zhu, Bin; Zhang, Feng; Bi, Bi; Zhang, Bo; Zhang, Zhimeng; Shui, Min; He, Yingling; Gu, Yuqiu, E-mail: yqgu@caep.cn; Zhang, Baohan [Science and Technology on Plasma Physics Laboratory, China Academy of Engineering Physics, Mianyang 621900 (China); Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900 (China); Peng, Xiaoshi; Xu, Tao; Wang, Feng; Yang, Zhiwen; Chen, Tao; Chen, Li; Chen, Ming [Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900 (China); and others

    2016-06-15

    During fast-ignition implosions, preheating of inside the cone tip caused by hard X-rays can strongly affect the generation and transport of hot electrons in the cone. Although indirect-drive implosions have a higher implosion symmetry, they cause stronger preheating effects than direct-drive implosions. To control the preheating of the cone tip, we propose the use of indirect-drive fast-ignition targets with thicker tips. Experiments carried out at the ShenGuang-III prototype laser facility confirmed that thicker tips are effective for controlling preheating. Moreover, these results were consistent with those of 1D radiation hydrodynamic simulations.

  7. Coronal Properties of the Seyfert 1.9 Galaxy MCG-05-23-016 Determined from Hard X-Ray Spectroscopy with NuSTAR

    DEFF Research Database (Denmark)

    Balokovic, M.; Matt, G.; Harrison, F. A.

    2015-01-01

    -23-016 with unprecedented precision. The high sensitivity of NuSTAR up to 79 keV allows us to clearly disentangle the spectral curvature of the primary continuum from that of its reflection component. Using a simple phenomenological model for the hard X-ray spectrum, we constrain the cut-off energy to keV with 90......% confidence. Testing for more complex models and nuisance parameters that could potentially influence the measurement, we find that the cut-off is detected robustly. We further use simple Comptonized plasma models to provide independent constraints for both the kinetic temperature of the electrons...

  8. Dual-array valence emission spectrometer (DAVES): A new approach for hard x-ray photon-in photon-out spectroscopies

    Energy Technology Data Exchange (ETDEWEB)

    Finkelstein, K. D., E-mail: kdf1@cornell.edu; Lyndaker, A.; Krawcyk, T.; Conrad, J. [CHESS Wilson Lab, Cornell University, Ithaca, NY 14853 (United States); Pollock, C. J. [Dept. of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States)

    2016-07-27

    CHESS has developed and successfully deployed a novel Dual Array Valence Emission Spectrometer (DAVES) for high energy resolution, hard x-ray spectroscopy. DAVES employs the simplest method for scanning multiple spherical crystals along a Rowland Circle. The new design achieves unique 2-color collection capability and is built to take special advantage of pixel array detectors. Our initial results show why these detectors greatly improve data quality. The presentation emphasizes flexibility of experimental design offered by DAVES. Prospects and benefits of 2-color spectroscopy are illustrated and discussed.

  9. Measurement of Hard Lags and Coherences in the X-Ray Flux of Accreting Neutron Stars and Comparison with Accreting Black Holes

    OpenAIRE

    Ford, Eric C.; Van Der Klis, Michiel; Mendez, Mariano; van Paradijs, Jan; Kaaret, Philip

    1998-01-01

    Using the Rossi X-ray Timing Explorer we have measured lags of the 9 to 33 keV photons relative to the 2 to 9 keV photons in the timing noise between 0.01 and 100 Hz in the accreting neutron stars 4U 0614+091 and 4U 1705-44. We performed similar measurements on the accreting black hole candidates Cyg X-1 and GX 339-4 as a comparison. During the observations these sources were all in low (hard) states. We find phase lags of between 0.03 and 0.2 radians in all these sources, with a variation in...

  10. Effective hard x-ray spectrum of a tabletop Mather-type plasma focus optimized for flash radiography of metallic objects

    Science.gov (United States)

    Raspa, V.; Moreno, C.; Sigaut, L.; Clausse, A.

    2007-12-01

    The effective spectrum of the hard x-ray output of a Mather-type tabletop plasma focus device was determined from attenuation data on metallic samples using commercial radiographic film coupled to a Gd2O2S:Tb phosphor intensifier screen. It was found that the radiation has relevant spectral components in the 40-150 keV range, with a single maximum around 60-80 keV. The radiation output allows for 50 ns resolution, good contrast, and introspective imaging of metallic objects even through metallic walls. A numerical estimation of the induced voltage on the focus during the compressional stage is briefly discussed.

  11. Combined Application of QEM-SEM and Hard X-ray Microscopy to Determine Mineralogical Associations and Chemcial Speciation of Trace Metals

    Energy Technology Data Exchange (ETDEWEB)

    M Grafe; M Landers; R Tappero; P Austin; B Gan; A Grabsch; C Klauber

    2011-12-31

    We describe the application of quantitative evaluation of mineralogy by scanning electron microscopy in combination with techniques commonly available at hard X-ray microprobes to define the mineralogical environment of a bauxite residue core segment with the more specific aim of determining the speciation of trace metals (e.g., Ti, V, Cr, and Mn) within the mineral matrix. Successful trace metal speciation in heterogeneous matrices, such as those encountered in soils or mineral residues, relies on a combination of techniques including spectroscopy, microscopy, diffraction, and wet chemical and physical experiments. Of substantial interest is the ability to define the mineralogy of a sample to infer redox behavior, pH buffering, and mineral-water interfaces that are likely to interact with trace metals through adsorption, coprecipitation, dissolution, or electron transfer reactions. Quantitative evaluation of mineralogy by scanning electron microscopy coupled with micro-focused X-ray diffraction, micro-X-ray fluorescence, and micro-X-ray absorption near edge structure (mXANES) spectroscopy provided detailed insights into the composition of mineral assemblages and their effect on trace metal speciation during this investigation. In the sample investigated, titanium occurs as poorly ordered ilmenite, as rutile, and is substituted in iron oxides. Manganese's spatial correlation to Ti is closely linked to ilmenite, where it appears to substitute for Fe and Ti in the ilmenite structure based on its mXANES signature. Vanadium is associated with ilmenite and goethite but always assumes the +4 oxidation state, whereas chromium is predominantly in the +3 oxidation state and solely associated with iron oxides (goethite and hematite) and appears to substitute for Fe in the goethite structure.

  12. Hard X-ray index of refraction tomography of a whole rabbit knee joint: A feasibility study.

    Science.gov (United States)

    Gasilov, S; Mittone, A; Horng, A; Geith, T; Bravin, A; Baumbach, T; Coan, P

    2016-12-01

    We report results of the computed tomography reconstruction of the index of refraction in a whole rabbit knee joint examined at the photon energy of 51keV. Refraction based images make it possible to delineate the bone, cartilage, and soft tissues without adjusting the contrast window width and level. Density variations, which are related to tissue composition and are not visible in absorption X-ray images, are detected in the obtained refraction based images. We discuss why refraction-based images provide better detectability of low contrast features than absorption images. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  13. NuSTAR and XMM-Newton Observations of the Hard X-Ray Spectrum of Centaurus A

    DEFF Research Database (Denmark)

    Fürst, F.; Müller, C.; Madsen, K. K.

    2016-01-01

    We present simultaneous XMM-Newton and NuSTAR observations spanning 3–78 keV of the nearest radiogalaxy, Centaurus A (Cen A), performed during a very high flux state. The accretion geometry around thecentral engine in Cen A is still debated, and we investigate possible configurations using detailed...... X-ray spectralmodeling. NuSTAR imaged the central region of Cen A with subarcminute resolution at X-ray energies above10 keV for the first time, but finds no evidence for an extended source or other off-nuclear point-sources.The XMM-Newton and NuSTAR spectra agree well and can be described...... with an absorbed power-law witha photon index Γ = 1.815 ± 0.005 and a fluorescent Fe Kα line in good agreement with literature values.The spectrum does not require a high-energy exponential rollover, with a constraint of Efold > 1 MeV. Athermal Comptonization continuum describes the data well, with parameters...

  14. THREE YEARS OF FERMI GBM EARTH OCCULTATION MONITORING: OBSERVATIONS OF HARD X-RAY/SOFT GAMMA-RAY SOURCES

    Energy Technology Data Exchange (ETDEWEB)

    Wilson-Hodge, Colleen A.; Jenke, Peter [ZP 12 Astrophysics Office, NASA Marshall Space Flight Center, Huntsville, AL 35812 (United States); Case, Gary L.; Cherry, Michael L.; Rodi, James [Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803 (United States); Camero-Arranz, Ascension [Instituto de Ciencias del Espacio (IEEC-CSIC), Campus UAB, Torre C5, 2a planta, 08193 Barcelona (Spain); Chaplin, Vandiver; Bhat, Narayan; Briggs, Michael S.; Connaughton, Valerie; Preece, Robert [Physics Department, University of Alabama in Huntsville, Huntsville, AL 35899 (United States); Beklen, Elif [Physics Department, Suleyman Demirel University, 32260 Isparta (Turkey); Finger, Mark; Paciesas, William S. [Universities Space Research Association, Huntsville, AL 35805 (United States); Greiner, Jochen; Meegan, Charles A.; Von Kienlin, Andreas [Max-Planck Institut fuer Extraterrestische Physik, D-85748 Garching (Germany); Kippen, R. Marc [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2012-08-01

    The Gamma-ray Burst Monitor (GBM) on board Fermi has been providing continuous data to the astronomical community since 2008 August 12. In this paper, we present the results of the analysis of the first three years of these continuous data using the Earth occultation technique to monitor a catalog of 209 sources. From this catalog, we detect 99 sources, including 40 low-mass X-ray binary/neutron star systems, 31 high-mass X-ray binary/neutron star systems, 12 black hole binaries, 12 active galaxies, and 2 other sources, plus the Crab Nebula, and the Sun. Nine of these sources are detected in the 100-300 keV band, including seven black hole binaries, the active galaxy Cen A, and the Crab. The Crab and Cyg X-1 are also detected in the 300-500 keV band. GBM provides complementary data to other sky-monitors below 100 keV and is the only all-sky monitor above 100 keV. Up-to-date light curves for all of the catalog sources can be found online.

  15. Catalog of hard X-ray solar flares detected with Mars Odyssey/HEND from the Mars orbit in 2001-2016

    Science.gov (United States)

    Livshits, M. A.; Zimovets, I. V.; Golovin, D. V.; Nizamov, B. A.; Vybornov, V. I.; Mitrofanov, I. G.; Kozyrev, A. S.; Litvak, M. L.; Sanin, A. B.; Tretyakov, V. I.

    2017-09-01

    The study of nonstationary processes in the Sun is of great interest, and multi-wavelength observations and the registration of magnetic fields have been carried out using both ground-based telescopes and several specialized spacecraft in near-Earth orbits in recent years. However, the acquisition of new, reliable information on their hard X-ray radiation remains necessary, in particular, if the corresponding spacecraft provide additional information, e.g., in regard to flare observations from directions other than the Sun-Earth direction. This paper presents a catalog of powerful solar flares registered by the High Energy Neutron Detector (HEND) designed at the Space Research Institute of the Russian Academy of Sciences. HEND is mounted onboard the 2001Mars Odyssey spacecraft. It operated successfully during the flight to Mars and is currently operating in near-Mars orbit. Apart from neutrons, HEND is sensitive to hard X-ray (up to 300 keV) and gamma-ray radiation (above 300 keV). This radiation is registered by two scintillators: an outer one that is sensitive to photons above 40 keV and an inner one sensitive to photons above 200 keV. The catalog was created using a new procedure for calibration of the data. For the most powerful 60 solar flares in the visible and far sides of the Sun (for a terrestrial observer), time profiles of the flare radiation summed over all channels of the X-ray, and in some cases the gamma-ray, bands are provided, as well as spectra and characteristics of power-law fits. The results of previous studies of the Sun using HEND and the potential for further use of these data are discussed.

  16. Characterization of Nb hydrides synthesized in high-pressure supercritical water by micro-beam hard X-ray photoelectron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Soda, Kazuo, E-mail: j45880a@nucc.cc.nagoya-u.ac.jp [Department of Quantum Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Kondo, Hiroki; Kato, Masahiko [Department of Quantum Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Shiraki, Tatsuhito [Department of Materials, Physics and Energy Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Niwa, Ken; Kusaba, Keiji; Hasegawa, Masashi [Department of Crystalline Materials Science, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Ikenaga, Eiji [Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan)

    2013-02-15

    Highlights: •Nb hydride specimens were synthesized in high-pressure supercritical water. •Synthesized specimens were characterized by hard X-ray photoelectron spectroscopy. •The synthesized Nb hydrides are covered with several 10 nm thick Nb oxides. •Nb hydrides are formed deep inside the specimens. -- Abstract: We have characterized Nb hydrides synthesized in high-pressure supercritical water by hard X-ray photoelectron spectroscopy. Comparison is made, in particular, of the Nb 2p core level spectra and valence band ones for the Nb hydride specimens in different stages of hydrogenation with those for Nb oxide and metallic references. The Nb 2p core level spectra of the Nb hydride specimens synthesized at relatively low temperature show an intense Nb{sub 2}O{sub 5} component and a shoulder structure, which is attributed to Nb hydrides, at the high binding energy side of a metallic component of the Nb metal. The valence band spectra of the Nb hydride specimens also show a broad band at the binding energy E{sub B} between 5 and 9 eV, which is ascribed mainly to Nb oxides. The present results indicate that the surface of the synthesized Nb hydrides is covered with several 10 nm thick Nb oxides and suggest that the Nb hydrides are formed deep inside the specimens. The Nb 2p chemical shift implies the Nb valence of +1.4 for the synthesized hydride NbH{sub x}.

  17. Advancing the Swift BAT All Sky Hard X-ray Survey to the NuSTAR and Astro-H Era

    Science.gov (United States)

    Koss, Michael

    We propose to re-start the processing of the Swift BAT hard X-ray survey which halted in 2010 due to a lack of funds. The additional five years of Swift will roughly double the exposure and include recent NuSTAR observations that provide a unique scientific opportunity to study: 1). the most Compton-thick AGN in the nearby universe, 2). longterm AGN variability above 10 keV, and 3). targeted searches for spectral features of supernova remnants and signatures of warm dark matter annihilation using stacking. Reprocessing the Swift Survey was recommended as an important task in the 2014 NASA Senior Review of missions where Swift was given the highest rating. We will also develop new software tools that should allow guest observers to access the BAT survey data in new and powerful ways to increase the scientific usefulness of the data. We will apply new techniques to increase the number of channels of the BAT spectra from 8 to finer resolutions for targeted spectroscopic searches (full resolution is 80 channels). We will also develop new software tools that allow time dependent spectral analysis of any catalog source, time and energy slices to produce an all sky source catalog, fluxes and upper limits for candidate hard X-ray sources chosen in another waveband, and the finally the ability to stack the BAT data for a pre-selected list of objects and energy bands.

  18. Center for X-ray Optics, 1988

    Energy Technology Data Exchange (ETDEWEB)

    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.

  19. Computer-Controlled Cylindrical Polishing Process for Development of Grazing Incidence Optics for Hard X-Ray Region

    Science.gov (United States)

    Khan, Gufran Sayeed; Gubarev, Mikhail; Speegle, Chet; Ramsey, Brian

    2010-01-01

    The presentation includes grazing incidence X-ray optics, motivation and challenges, mid spatial frequency generation in cylindrical polishing, design considerations for polishing lap, simulation studies and experimental results, future scope, and summary. Topics include current status of replication optics technology, cylindrical polishing process using large size polishing lap, non-conformance of polishin lap to the optics, development of software and polishing machine, deterministic prediction of polishing, polishing experiment under optimum conditions, and polishing experiment based on known error profile. Future plans include determination of non-uniformity in the polishing lap compliance, development of a polishing sequence based on a known error profile of the specimen, software for generating a mandrel polishing sequence, design an development of a flexible polishing lap, and computer controlled localized polishing process.

  20. New room temperature high resolution solid-state detector (CdZnTe) for hard x rays and gamma rays

    Science.gov (United States)

    Stewart, Amyelizabeth C.; Desai, Upendra D.

    1993-01-01

    The new CdZnTe high 'Z' material represents a significant improvement in detectors for high energy photons. With the thicknesses available, photons up to 100 keV can be efficiently detected. This material has a wide band gap of 1.5 - 2.2 eV which allows it to operate at room temperature while providing high spectral resolution. Results of resolution evaluations are presented. This detector can be used for high resolution spectral measurements of photons in x-ray and gamma-ray astronomy, offering a significant reduction in the weight, power, and volume of the detector system compared to more conventional detector types such as scintillation counters. In addition, the detector will have the simplicity and reliability of solid-state construction. The CdZnTe detector, as a new development, has not yet been evaluated in space. The Get Away Special program can provide this opportunity.

  1. Multiwavelength Study of Quiescent States of Mrk 421 with Unprecedented Hard X-Ray Coverage Provided by NuSTAR in 2013

    Science.gov (United States)

    Baloković, M.; Paneque, D.; Madejski, G.; Furniss, A.; Chiang, J.; Ajello, M.; Alexander, D. M.; Barret, D.; Blandford, R. D.; Boggs, S. E.; Christensen, F. E.; Craig, W. W.; Forster, K.; Giommi, P.; Grefenstette, B.; Hailey, C.; Harrison, F. A.; Hornstrup, A.; Kitaguchi, T.; Koglin, J. E.; Madsen, K. K.; Mao, P. H.; Miyasaka, H.; Mori, K.; Perri, M.; Pivovaroff, M. J.; Puccetti, S.; Rana, V.; Stern, D.; Tagliaferri, G.; Urry, C. M.; Westergaard, N. J.; Zhang, W. W.; Zoglauer, A.; NuSTAR Team; Archambault, S.; Archer, A.; Barnacka, A.; Benbow, W.; Bird, R.; Buckley, J. H.; Bugaev, V.; Cerruti, M.; Chen, X.; Ciupik, L.; Connolly, M. P.; Cui, W.; Dickinson, H. J.; Dumm, J.; Eisch, J. D.; Falcone, A.; Feng, Q.; Finley, J. P.; Fleischhack, H.; Fortson, L.; Griffin, S.; Griffiths, S. T.; Grube, J.; Gyuk, G.; Huetten, M.; Håkansson, N.; Holder, J.; Humensky, T. B.; Johnson, C. A.; Kaaret, P.; Kertzman, M.; Khassen, Y.; Kieda, D.; Krause, M.; Krennrich, F.; Lang, M. J.; Maier, G.; McArthur, S.; Meagher, K.; Moriarty, P.; Nelson, T.; Nieto, D.; Ong, R. A.; Park, N.; Pohl, M.; Popkow, A.; Pueschel, E.; Reynolds, P. T.; Richards, G. T.; Roache, E.; Santander, M.; Sembroski, G. H.; Shahinyan, K.; Smith, A. W.; Staszak, D.; Telezhinsky, I.; Todd, N. W.; Tucci, J. V.; Tyler, J.; Vincent, S.; Weinstein, A.; Wilhelm, A.; Williams, D. A.; Zitzer, B.; VERITAS Collaboration; Ahnen, M. L.; Ansoldi, S.; Antonelli, L. A.; Antoranz, P.; Babic, A.; Banerjee, B.; Bangale, P.; Barres de Almeida, U.; Barrio, J. A.; Becerra González, J.; Bednarek, W.; Bernardini, E.; Biasuzzi, B.; Biland, A.; Blanch, O.; Bonnefoy, S.; Bonnoli, G.; Borracci, F.; Bretz, T.; Carmona, E.; Carosi, A.; Chatterjee, A.; Clavero, R.; Colin, P.; Colombo, E.; Contreras, J. L.; Cortina, J.; Covino, S.; Da Vela, P.; Dazzi, F.; De Angelis, A.; De Lotto, B.; de Oña Wilhelmi, E.; Delgado Mendez, C.; Di Pierro, F.; Dominis Prester, D.; Dorner, D.; Doro, M.; Einecke, S.; Elsaesser, D.; Fernández-Barral, A.; Fidalgo, D.; Fonseca, M. V.; Font, L.; Frantzen, K.; Fruck, C.; Galindo, D.; García López, R. J.; Garczarczyk, M.; Garrido Terrats, D.; Gaug, M.; Giammaria, P.; Glawion (Eisenacher, D.; Godinović, N.; González Muñoz, A.; Guberman, D.; Hahn, A.; Hanabata, Y.; Hayashida, M.; Herrera, J.; Hose, J.; Hrupec, D.; Hughes, G.; Idec, W.; Kodani, K.; Konno, Y.; Kubo, H.; Kushida, J.; La Barbera, A.; Lelas, D.; Lindfors, E.; Lombardi, S.; Longo, F.; López, M.; López-Coto, R.; López-Oramas, A.; Lorenz, E.; Majumdar, P.; Makariev, M.; Mallot, K.; Maneva, G.; Manganaro, M.; Mannheim, K.; Maraschi, L.; Marcote, B.; Mariotti, M.; Martínez, M.; Mazin, D.; Menzel, U.; Miranda, J. M.; Mirzoyan, R.; Moralejo, A.; Moretti, E.; Nakajima, D.; Neustroev, V.; Niedzwiecki, A.; Nievas Rosillo, M.; Nilsson, K.; Nishijima, K.; Noda, K.; Orito, R.; Overkemping, A.; Paiano, S.; Palacio, J.; Palatiello, M.; Paoletti, R.; Paredes, J. M.; Paredes-Fortuny, X.; Persic, M.; Poutanen, J.; Prada Moroni, P. G.; Prandini, E.; Puljak, I.; Rhode, W.; Ribó, M.; Rico, J.; Rodriguez Garcia, J.; Saito, T.; Satalecka, K.; Scapin, V.; Schultz, C.; Schweizer, T.; Shore, S. N.; Sillanpää, A.; Sitarek, J.; Snidaric, I.; Sobczynska, D.; Stamerra, A.; Steinbring, T.; Strzys, M.; Takalo, L.; Takami, H.; Tavecchio, F.; Temnikov, P.; Terzić, T.; Tescaro, D.; Teshima, M.; Thaele, J.; Torres, D. F.; Toyama, T.; Treves, A.; Verguilov, V.; Vovk, I.; Ward, J. E.; Will, M.; Wu, M. H.; Zanin, R.; MAGIC Collaboration; Perkins, J.; Verrecchia, F.; Leto, C.; Böttcher, M.; Villata, M.; Raiteri, C. M.; Acosta-Pulido, J. A.; Bachev, R.; Berdyugin, A.; Blinov, D. A.; Carnerero, M. I.; Chen, W. P.; Chinchilla, P.; Damljanovic, G.; Eswaraiah, C.; Grishina, T. S.; Ibryamov, S.; Jordan, B.; Jorstad, S. G.; Joshi, M.; Kopatskaya, E. N.; Kurtanidze, O. M.; Kurtanidze, S. O.; Larionova, E. G.; Larionova, L. V.; Larionov, V. M.; Latev, G.; Lin, H. C.; Marscher, A. P.; Mokrushina, A. A.; Morozova, D. A.; Nikolashvili, M. G.; Semkov, E.; Smith, P. S.; Strigachev, A.; Troitskaya, Yu. V.; Troitsky, I. S.; Vince, O.; Barnes, J.; Güver, T.; Moody, J. W.; Sadun, A. C.; Sun, S.; Hovatta, T.; Richards, J. L.; Max-Moerbeck, W.; Readhead, A. C. R.; Lähteenmäki, A.; Tornikoski, M.; Tammi, J.; Ramakrishnan, V.; Reinthal, R.; Angelakis, E.; Fuhrmann, L.; Myserlis, I.; Karamanavis, V.; Sievers, A.; Ungerechts, H.; Zensus, J. A.

    2016-03-01

    We present coordinated multiwavelength observations of the bright, nearby BL Lacertae object Mrk 421 taken in 2013 January-March, involving GASP-WEBT, Swift, NuSTAR, Fermi-LAT, MAGIC, VERITAS, and other collaborations and instruments, providing data from radio to very high energy (VHE) γ-ray bands. NuSTAR yielded previously unattainable sensitivity in the 3-79 keV range, revealing that the spectrum softens when the source is dimmer until the X-ray spectral shape saturates into a steep {{Γ }}≈ 3 power law, with no evidence for an exponential cutoff or additional hard components up to ˜80 keV. For the first time, we observed both the synchrotron and the inverse-Compton peaks of the spectral energy distribution (SED) simultaneously shifted to frequencies below the typical quiescent state by an order of magnitude. The fractional variability as a function of photon energy shows a double-bump structure that relates to the two bumps of the broadband SED. In each bump, the variability increases with energy, which, in the framework of the synchrotron self-Compton model, implies that the electrons with higher energies are more variable. The measured multi band variability, the significant X-ray-to-VHE correlation down to some of the lowest fluxes ever observed in both bands, the lack of correlation between optical/UV and X-ray flux, the low degree of polarization and its significant (random) variations, the short estimated electron cooling time, and the significantly longer variability timescale observed in the NuSTAR light curves point toward in situ electron acceleration and suggest that there are multiple compact regions contributing to the broadband emission of Mrk 421 during low-activity states.

  2. The NuSTAR  Extragalactic Surveys: X-Ray Spectroscopic Analysis of the Bright Hard-band Selected Sample

    Science.gov (United States)

    Zappacosta, L.; Comastri, A.; Civano, F.; Puccetti, S.; Fiore, F.; Aird, J.; Del Moro, A.; Lansbury, G. B.; Lanzuisi, G.; Goulding, A.; Mullaney, J. R.; Stern, D.; Ajello, M.; Alexander, D. M.; Ballantyne, D. R.; Bauer, F. E.; Brandt, W. N.; Chen, C.-T. J.; Farrah, D.; Harrison, F. A.; Gandhi, P.; Lanz, L.; Masini, A.; Marchesi, S.; Ricci, C.; Treister, E.

    2018-02-01

    We discuss the spectral analysis of a sample of 63 active galactic nuclei (AGN) detected above a limiting flux of S(8{--}24 {keV})=7× {10}-14 {erg} {{{s}}}-1 {{cm}}-2 in the multi-tiered NuSTAR extragalactic survey program. The sources span a redshift range z=0{--}2.1 (median =0.58). The spectral analysis is performed over the broad 0.5–24 keV energy range, combining NuSTAR with Chandra and/or XMM-Newton data and employing empirical and physically motivated models. This constitutes the largest sample of AGN selected at > 10 {keV} to be homogeneously spectrally analyzed at these flux levels. We study the distribution of spectral parameters such as photon index, column density ({N}{{H}}), reflection parameter ({\\boldsymbol{R}}), and 10–40 keV luminosity ({L}{{X}}). Heavily obscured ({log}[{N}{{H}}/{{cm}}-2]≥slant 23) and Compton-thick (CT; {log}[{N}{{H}}/{{cm}}-2]≥slant 24) AGN constitute ∼25% (15–17 sources) and ∼2–3% (1–2 sources) of the sample, respectively. The observed {N}{{H}} distribution agrees fairly well with predictions of cosmic X-ray background population-synthesis models (CXBPSM). We estimate the intrinsic fraction of AGN as a function of {N}{{H}}, accounting for the bias against obscured AGN in a flux-selected sample. The fraction of CT AGN relative to {log}[{N}{{H}}/{{cm}}-2]=20{--}24 AGN is poorly constrained, formally in the range 2–56% (90% upper limit of 66%). We derived a fraction (f abs) of obscured AGN ({log}[{N}{{H}}/{{cm}}-2]=22{--}24) as a function of {L}{{X}} in agreement with CXBPSM and previous z< 1 X-ray determinations. Furthermore, f abs at z=0.1{--}0.5 and {log}({L}{{x}}/{erg} {{{s}}}-1)≈ 43.6{--}44.3 agrees with observational measurements/trends obtained over larger redshift intervals. We report a significant anti-correlation of R with {L}{{X}} (confirmed by our companion paper on stacked spectra) with considerable scatter around the median R values.

  3. CdTe Timepix detectors for single-photon spectroscopy and linear polarimetry of high-flux hard x-ray radiation

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, C., E-mail: christoph.hahn@uni-jena.de; Höfer, S.; Kämpfer, T. [Helmholtz Institute Jena, 07743 Jena (Germany); Institute of Optics and Quantum Electronics, University of Jena, 07743 Jena (Germany); Weber, G.; Märtin, R. [Helmholtz Institute Jena, 07743 Jena (Germany); GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt (Germany); Stöhlker, Th. [Helmholtz Institute Jena, 07743 Jena (Germany); Institute of Optics and Quantum Electronics, University of Jena, 07743 Jena (Germany); GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt (Germany)

    2016-04-15

    Single-photon spectroscopy of pulsed, high-intensity sources of hard X-rays — such as laser-generated plasmas — is often hampered by the pileup of several photons absorbed by the unsegmented, large-volume sensors routinely used for the detection of high-energy radiation. Detectors based on the Timepix chip, with a segmentation pitch of 55 μm and the possibility to be equipped with high-Z sensor chips, constitute an attractive alternative to commonly used passive solutions such as image plates. In this report, we present energy calibration and characterization measurements of such devices. The achievable energy resolution is comparable to that of scintillators for γ spectroscopy. Moreover, we also introduce a simple two-detector Compton polarimeter setup with a polarimeter quality of (98 ± 1)%. Finally, a proof-of-principle polarimetry experiment is discussed, where we studied the linear polarization of bremsstrahlung emitted by a laser-driven plasma and found an indication of the X-ray polarization direction depending on the polarization state of the incident laser pulse.

  4. Flares from a new Integral hard X-ray source, IGR J17407-2808, likely associated with the ROSAT source SBM 10

    DEFF Research Database (Denmark)

    Kretschmar, P.; Mereghetti, S.; Hermsen, W.

    2004-01-01

    This new hard X-ray source, IGR J17407-2808, is positionally coincident with a faint ROSAT source listed as no. 10 in the catalogue of sources in the Galactic Center region by Sidoli, Belloni & Mereghetti 2001, A&A 368, 835 and as 2RXP J174040.9-280852 in the ROSAT Source Browser. No other......). The source was outside the FOV of the JEM-X and OMC monitor instruments during this flare. Note that the position of J17407-2808 is inconsistent with that of the X-ray burster SLX 1737-282 [AX J1740.7-2818] (in't Zand et al. 2002, A&A 389, L43), which is just ~11 arcmin away. The correct Integral attitude...... was not detected. The last flare, with peak fluxes of 0.8±0.1 Crab and 0.6±0.1 Crab in the energy ranges 20-40 keV and 40-60 keV respectively, triggered an automatic alert message of the Integral Burst Alert System (IBAS Alert #2010) which led to the discovery of the source (Gotz et al., GCN Circ. #2793...

  5. Bent crystals by surface grooving method for high-efficiency concentration of hard x-ray photons by a Laue lens

    Science.gov (United States)

    Guidi, V.; Barrière, N.; Bellucci, V.; Camattari, R.; Neri, I.

    2011-09-01

    We present an experimental study on the method of surface grooving for bending crystals for the realization of a hard x-ray Laue lens. Bent Si and Ge crystalline plates were analyzed by x-ray diffraction of their (111) planes at the European Synchrotron Radiation Facility. Crystals diffracted photons from 150 to 700 keV with efficiency peaking 95% at 150 keV for Si. Measured rocking curves of the samples showed flat-topped profiles with their FWHM equal to the crystal bending, i.e., the method of surface grooving proved to evenly bend the crystals, their energy passband being very well controlled. Surface grooving technique has been found to offer both high reproducibility and easy control of diffraction properties of the crystals. Besides, this method is cheap, simple and compatible with mass production, making it a reliable technique for fabrication of a Laue lens, where serial production of crystals should be envisaged. A Laue lens made of crystals bent by surface grooves can lead to significant detection improvement in astrophysical applications.

  6. Development of a compact radiation-hardened low-noise front-end readout ASIC for CZT-based hard X-ray imager

    Science.gov (United States)

    Gao, W.; Gan, B.; Li, X.; Wei, T.; Gao, D.; Hu, Y.

    2015-04-01

    In this paper, we present the development and performances of a radiation-hardened front-end readout application-specific integrated circuit (ASIC) dedicated to CZT detectors for a hard X-ray imager in space applications. The readout channel consists of a charge sensitive amplifier (CSA), a CR-RC shaper, a fast shaper, a discriminator and a driving buffer. With the additional digital filtering, the readout channel can achieve very low noise performances and low power dissipation. An eight-channel prototype ASIC is designed and fabricated in 0.35 μm CMOS process. The energy range of the detected X-rays is evaluated as 1.45 keV to 281 keV. The gain is larger than 100 mV/fC. The equivalent noise charge (ENC) of the ASIC is 53 e- at zero farad plus 10 e- per picofarad. The power dissipation is less than 4.4 mW/channel. Through the measurement with a CZT detector, the energy resolution is less than 3.45 keV (FWHM) under the irradiation of the radioactive source 241Am. The radiation effect experiments indicate that the proposed ASIC can resist the total ionization dose (TID) irradiation of higher than 200 krad (Si).

  7. The hard X-ray view of the young supernova remnant G1.9+0.3

    DEFF Research Database (Denmark)

    Zoglauer, Andreas; Reynolds, Stephen P.; An, Hongjun

    2015-01-01

    NuSTAR observed G1.9+0.3, the youngest known supernova remnant in the Milky Way, for 350 ks and detected emission up to ~30 keV. The remnant's X-ray morphology does not change significantly across the energy range from 3 to 20 keV. A combined fit between NuSTAR and Chandra shows that the spectrum....... This can be explained by particle acceleration, to a maximum energy set by the finite remnant age, in a magnetic field of about 10 μG, for which our roll-off implies a maximum energy of about 100 TeV for both electrons and ions. Much higher magnetic-field strengths would produce an electron spectrum...... that was cut off by radiative losses, giving a much higher roll-off frequency that is independent of magnetic-field strength. In this case, ions could be accelerated to much higher energies. A search for 44Ti emission in the 67.9 keV line results in an upper limit of 1.5 × 10-5 photons cm-2 s-1 assuming a line...

  8. Optical Studies of 13 Hard X-Ray Selected Cataclysmic Binaries from the Swift-BAT Survey

    Science.gov (United States)

    Halpern, Jules P.; Thorstensen, John R.

    2015-12-01

    From a set of 13 cataclysmic binaries that were discovered in the Swift Burst Alert Telescope (BAT) survey, we conducted time-resolved optical spectroscopy and/or time-series photometry of 11, with the goal of measuring their orbital periods and searching for spin periods. Seven of the objects in this study are new optical identifications. Orbital periods are found for seven targets, ranging from 81 minutes to 20.4 hr. PBC J0706.7+0327 is an AM Herculis star (polar) based on its emission-line variations and large amplitude photometric modulation on the same period. Swift J2341.0+7645 may be a polar, although the evidence here is less secure. Coherent pulsations are detected from two objects, Swift J0503.7-2819 (975 s) and Swift J0614.0+1709 (1412 s and 1530 s, spin and beat periods, respectively), indicating that they are probable intermediate polars (DQ Herculis stars). For two other stars, longer spin periods are tentatively suggested. We also present the discovery of a 2.00 hr X-ray modulation from RX J2015.6+3711, possibly a contributor to Swift J2015.9+3715, and likely a polar. Based on observations obtained at the MDM Observatory, operated by Dartmouth College, Columbia University, Ohio State University, Ohio University, and the University of Michigan.

  9. Spherical analyzers and monochromators for resonant inelastic hard X-ray scattering: a compilation of crystals and reflections.

    Science.gov (United States)

    Gog, Thomas; Casa, Diego M; Said, Ayman H; Upton, Mary H; Kim, Jungho; Kuzmenko, Ivan; Huang, XianRong; Khachatryan, Ruben

    2013-01-01

    Resonant inelastic X-ray scattering (RIXS) experiments require special sets of near-backscattering spherical diced analyzers and high-resolution monochromators for every distinct absorption-edge energy and emission line. For the purpose of aiding the design and planning of efficient RIXS experiments, comprehensive lists of suitable analyzer reflections for silicon, germanium, α-quartz, sapphire and lithium niobate crystals were compiled for a multitude of absorption edges and emission lines. Analyzers made from lithium niobate, sapphire or α-quartz offer many choices of reflections with intrinsic resolutions currently unattainable from silicon or germanium. In some cases these materials offer higher intensities at comparable resolutions. While lithium niobate, sapphire or α-quartz analyzers are still in an early stage of development, the present compilation can serve as a computational basis for assessing expected and actual performance. With regard to high-resolution monochromators, bandpass and throughput calculations for combinations of double-crystal, high-heat-load and near-backscattering high-resolution channel-cuts were assembled. The compilation of these analyzer and monochromator data is publicly available on a website.

  10. Combining Coherent Hard X-Ray Tomographies with Phase Retrieval to Generate Three-Dimensional Models of Forming Bone

    Directory of Open Access Journals (Sweden)

    Emely L. Bortel

    2017-11-01

    Full Text Available Holotomography, a phase-sensitive synchrotron-based (µCT modality, is a quantitative 3D imaging method. By exploiting partial spatial X-ray coherence, bones can be imaged volumetrically with high resolution coupled with impressive density sensitivity. This tomographic method reveals the main characteristics of the important tissue compartments in forming bones, including the rapidly changing soft tissue and the partially or fully mineralized bone regions, while revealing subtle density differences in 3D. Here, we show typical results observed within the growing femur bone midshafts of healthy mice that are 1, 3, 7, 10, and 14 days old (postpartum. Our results make use of partially coherent synchrotron radiation employing inline Fresnel propagation in multiple tomographic datasets obtained in the imaging beamline ID19 of the European Synchrotron Radiation Facility. The exquisite detail creates maps of the juxtaposed soft, partially mineralized and highly mineralized bone revealing the environment in which bone cells create and shape the matrix. This high-resolution 3D data can be used to create detailed computational models to study the dynamic processes involved in bone tissue formation and adaptation. Such data can enhance our understanding of the important biomechanical interactions directing maturation and shaping of the bone micro- and macro-geometries.

  11. In situ synchrotron high-energy X-ray diffraction study of microscopic deformation behavior of a hard-soft dual phase composite containing phase transforming matrix

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Junsong; Hao, Shijie; Jiang, Daqiang; Huan, Yong; Cui, Lishan; Liu, Yinong; Yang, Hong; Ren, Yang

    2017-05-01

    This study explored a novel intermetallic composite design concept based on the principle of lattice strain matching enabled by the collective atomic load transfer. It investigated the hard-soft microscopic deformation behavior of a Ti3Sn/TiNi eutectic hard-soft dual phase composite by means of in situ synchrotron high-energy X-ray diffraction (HE-XRD) during compression. The composite provides a unique micromechanical system with distinctive deformation behaviors and mechanisms from the two components, with the soft TiNi matrix deforming in full compliance via martensite variant reorientation and the hard Ti3Sn lamellae deforming predominantly by rigid body rotation, producing a crystallographic texture for the TiNi matrix and a preferred alignment for the Ti3Sn lamellae. HE-XRD reveals continued martensite variant reorientation during plastic deformation well beyond the stress plateau of TiNi. The hard and brittle Ti3Sn is also found to produce an exceptionally large elastic strain of 1.95% in the composite. This is attributed to the effect of lattice strain matching between the transformation lattice distortion of the TiNi matrix and the elastic strain of Ti3Sn lamellae. With such unique micromechanic characteristics, the composite exhibits high strength and large ductility.

  12. Near edge X-ray absorption fine structure study for optimization of hard diamond-like carbon film formation with Ar cluster ion beam

    CERN Document Server

    Kitagawa, T; Kanda, K; Shimizugawa, Y; Toyoda, N; Matsui, S; Yamada, I; Tsubakino, H; Matsuo, J

    2003-01-01

    Diamond-like carbon (DLC) film deposited using C sub 6 sub 0 vapor with simultaneous irradiation of an Ar cluster ion beam was characterized by a near edge X-ray absorption fine structure (NEXAFS), in order to optimize the hard DLC film deposition conditions. Contents of sp sup 2 orbitals in the films, which were estimated from NEXAFS spectra, are 30% lower than that of a conventional DLC film deposited by a RF plasma method. Those contents were obtained under the flux ratio of the C sub 6 sub 0 molecules to the Ar cluster ions to range from 1 to 20, at 5keV of Ar cluster ion acceleration energy. Average hardness of the films was 50 GPa under these flux ratios. This hardness was three times higher than that of a conventional DLC film. Furthermore, the lowest sp sup 2 content and above-mentioned high hardness were obtained at room temperature of the substrate when the depositions were performed in the range of the substrate temperature from room temperature to 250degC. (author)

  13. Strong valence fluctuation in the quantum critical heavy fermion superconductor β-YbAlB4: a hard x-ray photoemission study.

    Science.gov (United States)

    Okawa, M; Matsunami, M; Ishizaka, K; Eguchi, R; Taguchi, M; Chainani, A; Takata, Y; Yabashi, M; Tamasaku, K; Nishino, Y; Ishikawa, T; Kuga, K; Horie, N; Nakatsuji, S; Shin, S

    2010-06-18

    Electronic structures of the quantum critical superconductor β-YbAlB4 and its polymorph α-YbAlB4 are investigated by using bulk-sensitive hard x-ray photoemission spectroscopy. From the Yb 3d core level spectra, the values of the Yb valence are estimated to be ∼2.73 and ∼2.75 for α- and β-YbAlB4, respectively, thus providing clear evidence for valence fluctuations. The valence band spectra of these compounds also show Yb2+ peaks at the Fermi level. These observations establish an unambiguous case of a strong mixed valence at quantum criticality for the first time among heavy fermion systems, calling for a novel scheme for a quantum critical model beyond the conventional Doniach picture in β-YbAlB4.

  14. Electronic structure of delta-doped La:SrTiO{sub 3} layers by hard x-ray photoelectron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, A. M. [Department of Physics, University of California, Davis, California 95616 (United States); Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Peter-Gruenberg-Institut PGI-6, Forschungszentrum Juelich, 52425 Juelich (Germany); Gray, A. X. [Department of Physics, University of California, Davis, California 95616 (United States); Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Conti, G.; Fadley, C. S. [Department of Physics, University of California, Davis, California 95616 (United States); Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Jalan, B. [Materials Department, University of California, Santa Barbara, California 93106-5050 (United States); Department of Chemical Engineering and Materials Science, University of Minnesota, Twin Cities, Minnesota 55455 (United States); Kajdos, A. P.; Stemmer, S. [Materials Department, University of California, Santa Barbara, California 93106-5050 (United States); Gloskovskii, A. [Institut fuer Anorganische Chemie und Analytische Chemie, Johannes Gutenberg-Universitaet, 55099 Mainz (Germany); Ueda, S.; Yamashita, Y.; Kobayashi, K. [NIMS Beamline Station at SPring-8, National Institute for Materials Science, Hyogo 679-5148 (Japan); Drube, W. [Deutsches Elektronen-Synchrotron (DESY), Notkestrasse 85, 22607 Hamburg (Germany)

    2012-06-25

    We have employed hard x-ray photoemission (HAXPES) to study a delta-doped SrTiO{sub 3} layer that consisted of a 3-nm thickness of La-doped SrTiO{sub 3} with 6% La embedded in a SrTiO{sub 3} film. Results are compared to a thick, uniformily doped La:SrTiO{sub 3} layer. We find no indication of a band offset for the delta-doped layer, but evidence of the presence of Ti{sup 3+} in both the thick sample and the delta-layer, and indications of a density of states increase near the Fermi energy in the delta-doped layer. These results further demonstrate that HAXPES is a powerful tool for the non-destructive investigation of deeply buried doped layers.

  15. Flight performance of an advanced CZT imaging detector in a balloon-borne wide-field hard X-ray telescope—ProtoEXIST1

    Science.gov (United States)

    Hong, J.; Allen, B.; Grindlay, J.; Barthelemy, S.; Baker, R.; Garson, A.; Krawczynski, H.; Apple, J.; Cleveland, W. H.

    2011-10-01

    We successfully carried out the first high-altitude balloon flight of a wide-field hard X-ray coded-aperture telescope ProtoEXIST1, which was launched from the Columbia Scientific Balloon Facility at Ft. Sumner, New Mexico on October 9, 2009. ProtoEXIST1 is the first implementation of an advanced CdZnTe (CZT) imaging detector in our ongoing program to establish the technology required for next generation wide-field hard X-ray telescopes such as the High Energy Telescope (HET) in the Energetic X-ray Imaging Survey Telescope (EXIST). The CZT detector plane in ProtoEXIST1 consists of an 8×8 array of closely tiled 2 cm×2 cm×0.5 cm thick pixellated CZT crystals, each with 8×8 pixels, mounted on a set of readout electronics boards and covering a 256 cm2 active area with 2.5 mm pixels. A tungsten mask, mounted at 90 cm above the detector provides shadowgrams of X-ray sources in the 30-600 keV band for imaging, allowing a fully coded field of view of 9°×9° (and 19°×19° for 50% coding fraction) with an angular resolution of 20‧. In order to reduce the background radiation, the detector is surrounded by semi-graded (Pb/Sn/Cu) passive shields on the four sides all the way to the mask. On the back side, a 26 cm×26 cm×2 cm CsI(Na) active shield provides signals to tag charged particle induced events as well as ≳100keV background photons from below. The flight duration was only about 7.5 h due to strong winds (60 knots) at float altitude (38-39 km). Throughout the flight, the CZT detector performed excellently. The telescope observed Cyg X-1, a bright black hole binary system, for ˜1h at the end of the flight. Despite a few problems with the pointing and aspect systems that caused the telescope to track about 6.4° off the target, the analysis of the Cyg X-1 data revealed an X-ray source at 7.2σ in the 30-100 keV energy band at the expected location from the optical images taken by the onboard daytime star camera. The success of this first flight is very

  16. Spectroscopic Imaging Using Ge and CdTe Based Detector Systems for Hard X-ray Applications

    Science.gov (United States)

    Astromskas, Vytautas

    Third generation synchrotron facilities such as the Diamond Light Source (DLS) have a wide range of experiments performed for a wide range of science fields. The DLS operates at energies up to 150 keV which introduces great challenges to radiation detector technology. This work focuses on the requirements that the detector technology faces for X-ray Absorption Fine Structure (XAFS) and powder diffraction experiments in I12 and I15 beam lines, respectively. A segmented HPGe demonstrator detector with in-built charge sensitive CUBE preamplifiers and a Schottky e- collection CdTe Medipix3RX detector systems were investigated to understand the underlying mechanisms that limit spectroscopic, imaging performances and stability and to find ways to overcome or minimise those limitations. The energy resolution and stability of the Ge demonstrator detector was found to have the required characteristics for XAFS measurements. Charge sharing was identified as a limiting factor to the resolution which is going to be addressed in the future development of a full detector system as well as reductions in electronic noise and cross-talk effects. The stability study of the Schottky CdTe Medipix3RX detector showed that polarization is highly dependent on temperature, irradiation duration and incoming flux. A new pixel behaviour called tri-phase (3-P) pixel was identified and a novel method for determining optimum operational conditions was developed. The use of the 3-P pixels as a criterion for depolarization resulted in a stable performance of the detector. Furthermore, the detector was applied in powder diffraction measurement at the I15 beam line and resulted in the detector diffraction pattern matching the simulated data. CdTe Medipix3RX and HEXITEC spectroscopic imaging detectors were applied in identification and discrimination of transitional metals for security application and K-edge subtraction for medical applications. The results showed that both detectors have potential

  17. Joint x-ray

    Science.gov (United States)

    X-ray - joint; Arthrography; Arthrogram ... x-ray technologist will help you position the joint to be x-rayed on the table. Once in place, pictures are taken. The joint may be moved into other positions for more ...

  18. GAMMA-RAY AND HARD X-RAY EMISSION FROM PULSAR-AIDED SUPERNOVAE AS A PROBE OF PARTICLE ACCELERATION IN EMBRYONIC PULSAR WIND NEBULAE

    Energy Technology Data Exchange (ETDEWEB)

    Murase, Kohta [Institute for Advanced Study, Princeton, NJ 08540 (United States); Kashiyama, Kazumi [Center for Particle and Gravitational Astrophysics, Department of Physics, Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States); Kiuchi, Kenta [Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto, Kyoto 606-8502 (Japan); Bartos, Imre [Department of Physics, Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States)

    2015-05-20

    It has been suggested that some classes of luminous supernovae (SNe) and gamma-ray bursts (GRBs) are driven by newborn magnetars. Fast-rotating proto-neutron stars have also been of interest as potential sources of gravitational waves (GWs). We show that for a range of rotation periods and magnetic fields, hard X-rays and GeV gamma rays provide us with a promising probe of pulsar-aided SNe. It is observationally known that young pulsar wind nebulae (PWNe) in the Milky Way are very efficient lepton accelerators. We argue that, if embryonic PWNe satisfy similar conditions at early stages of SNe (in ∼1–10 months after the explosion), external inverse-Compton emission via upscatterings of SN photons is naturally expected in the GeV range as well as broadband synchrotron emission. To fully take into account the Klein–Nishina effect and two-photon annihilation process that are important at early times, we perform detailed calculations including electromagnetic cascades. Our results suggest that hard X-ray telescopes such as NuSTAR can observe such early PWN emission by follow-up observations in months to years. GeV gamma-rays may also be detected by Fermi for nearby SNe, which serve as counterparts of these GW sources. Detecting the signals will give us an interesting probe of particle acceleration at early times of PWNe, as well as clues to driving mechanisms of luminous SNe and GRBs. Since the Bethe–Heitler cross section is lower than the Thomson cross section, gamma rays would allow us to study subphotospheric dissipation. We encourage searches for high-energy emission from nearby SNe, especially SNe Ibc including super-luminous objects.

  19. Hard X-ray Emission along the Z Track in GX 17+2 GQ Ding∗ & CP ...

    Indian Academy of Sciences (India)

    the hard tail is detected on the horizontal branch (HB) and it gradually fades away as they moves along the Z ... along the Z track on their HIDs, and, finally, become lowest on the flaring branch. (FB) (Penninx et al. .... use the data from cluster A, because detector 2 of cluster B loses its spectral capabil- ity and automatic gain ...

  20. Preliminary design of a zone plate based hard X-ray monochromatic diffraction nanoprobe for materials studies at APS

    Science.gov (United States)

    Cai, Zhonghou; Liu, Wenjun; Tischler, Jonathan Z.; Shu, Deming; Xu, Ruqing; Schmidt, Oliver

    2013-09-01

    Aiming at studies of the micro/nano-structures of a broad range materials and electronic devices, Advance Photon Source (APS) is developing a dedicated diffraction nanoprobe (DNP) beamline for the needs arising from a multidiscipline research community. As a part of the APS Upgrade Project, the planed facility, named Sub-micron 3-D Diffraction (S3DD) beamline1, integrates the K-B mirror based polychromatic Laue diffraction and the Fresnel zone-plate based monochromatic diffraction techniques that currently support 3D/2D microdiffraction programs at the 34-ID-E and 2-ID-D of the APS, respectively. Both diffraction nanoprobes are designed to have a 50-nm or better special resolution. The zone-plate based monochromatic DNP has been preliminarily designed and will be constructed at the sector 34-ID. It uses an APS-3.0-cm period or APS-3.3-cm period undulator, a liquid-nitrogen cooled mirror as its first optics, and a water cooled small gap silicon double-crystal monochromator with an energy range of 5-30 keV. A set of zone plates have been designed to optimize for focusing efficiency and the working distance based on the attainable beamline length and the beam coherence. To ensure the nanoprobe performance, high stiffness and high precision flexure stage systems have been designed or demonstrated for optics mounting and sample scanning, and high precision temperature control of the experimental station will be implemented to reduce thermal instability. Designed nanoprobe beamline has a good management on thermal power loading on optical components and allows high degree of the preservation of beam brilliance for high focal flux and coherence. Integrated with variety of X-ray techniques, planed facility provides nano-XRD capability with the maximum reciprocal space accessibility and allows micro/nano-spectroscopy studies with K-edge electron binding energies of most elements down to Vanadium in the periodic table. We will discuss the preliminary design of the zone

  1. Hard X-ray/IR spectral-imaging of GRBs from the high-z Universe to EXIST

    Science.gov (United States)

    Grindlay, Jonathan

    The re-configured Energetic X-ray Imaging Survey Telescope (EXIST ) mission is optimized for study of GRBs as probes of the high-z Universe. The primary High Energy Telescope (HET) on EXIST maintains its high sensitivity (> 4 - 10X that of Swift) and bandwidth (5-600 keV) but has improved its angular resolution ( 5σ survey threshold) while fitting into a lower cost launch vehicle with greatly reduced mission mass and cost by reducing (by 2X) its instantaneous FoV (to ˜1.5sr, fully coded). This allows full-sky coverage every 2 orbits of survey and, most importantly, the addition of a co-aligned 1.1m IR telescope (IRT) with objective prism (R ˜10) and slit spectroscopy (R ˜1500) simultaneously (with dichroic) in the optical (0.3-1µ) and IR (0.9-2.5µ) bands. Rapid (˜100sec) slews onto GRBs allow determination onboard of GRB optical/IR counterparts and immediate spectra and redshifts. With radiative cooling (-30C) of the primary and secondary mirrors of the IRT, the low backgrounds permit IRT discovery objective prism spectra (R ˜10) on all objects in a 5 x 5arcmin field down to magnitude AB(H) ˜24 within ˜600sec. This will enable rapid measurements of redshifts and followup R ˜1500 longer exposure narrow slit spectra for studies of cosmic re-ionization. EXIST will detect ˜700 GRBs per year, with >70 per year likely to be at z > 6. This will enable comprehensive measures of cosmic structure, along many lines of sight, and constrain the growth of galaxies as well as possibly Pop III stars at redshifts as high as z ˜20. EXIST was selected under the Advanced Mission Concept Study (AMCS) program and is under a 1y study for science and mission optimization for presentation to the upcoming Decadal Survey. Its technical readiness would allow a launch as a Medium Class mission as early as ˜2015, particularly if international partnership(s) could enable an equatorial non- NASA launch. The overall mission science and concept will be presented.

  2. X-ray Measurements of Black Hole X-ray Binary Source GRS 1915+ ...

    Indian Academy of Sciences (India)

    tribpo

    X-ray Measurements of Black Hole X-ray Binary Source GRS. 1915+105 and the Evolution of Hard X-ray Spectrum. R. K. Manchanda, Tata Institute of Fundamental Research, Mumbai 400 005, India,. Received 1999 December 28; accepted 2000 February 9. Abstract. We report the spectral measurement of GRS 1915+105 ...

  3. INTEGRAL observations of the GeV blazar PKS 1502+106 and the hard X-ray bright Seyfert galaxy Mkn 841

    Science.gov (United States)

    Pian, E.; Ubertini, P.; Bazzano, A.; Beckmann, V.; Eckert, D.; Ghisellini, G.; Pursimo, T.; Tagliaferri, G.; Tavecchio, F.; Türler, M.; Bianchi, S.; Bianchin, V.; Hudec, R.; Maraschi, L.; Raiteri, C. M.; Soldi, S.; Treves, A.; Villata, M.

    2011-02-01

    Context. Extragalactic nuclear activity is most effectively explored with observations at high energies, where the most extreme flux and spectral variations are expected to occur, because of changes in either the accretion flow or the kinematics of the plasma. In active galactic nuclei of blazar type, these variations are the most dramatic. Aims: By following blazar outbursts from their onset and correlating the observed variations at many different wavelengths, we can reconstruct the behavior of the plasma and map out the development of the flare within the jet. Methods: The advent of the Fermi satellite has allowed the start of a systematic and intensive monitoring program of blazars. Blazar outbursts are very effectively detected by the LAT instrument in the MeV-GeV domain, and these can be promptly followed up with other facilities. Based on a Fermi LAT detection of a high MeV-GeV state, we observed the blazar PKS 1502+106 with the INTEGRAL satellite between 9 and 11 August 2008. Simultaneous Swift observations were also accomplished, as well as optical follow-up at the Nordic Optical Telescope. Results: The IBIS instrument onboard INTEGRAL detected a source at a position inconsistent with the optical coordinates of PKS 1502+106, but consistent with those of the Seyfert 1 galaxy Mkn 841, located at 6.8 arcmin south-west of the blazar, which is therefore responsible for all the hard X-ray flux detected by IBIS. At the location of the blazar, IBIS sets an upper limit of ~ 10-11 erg s-1 cm-2 on the 15-60 keV flux, which is consistent with a model of inverse Compton scattering accounting for the soft X-ray and gamma-ray spectra measured by Swift XRT and Fermi LAT, respectively. The gamma-ray spectrum during the outburst indicates substantial variability in the characteristic energy of the inverse Compton component in this blazar. The hard X-ray state of the Seyfert appears to be nearly unchanged with respect to the past. On the other hand, its soft X-ray flux (0

  4. Fine-Pitch CdTe Detector for Hard X-Ray Imaging and Spectroscopy of the Sun with the FOXSI Rocket Experiment

    Science.gov (United States)

    Ishikawa, Shin-nosuke; Katsuragawa, Miho; Watanabe, Shin; Uchida, Yuusuke; Takeda, Shin'lchiro; Takahashi, Tadayuki; Saito, Shinya; Glesener, Lindsay; Bultrago-Casas, Juan Camilo; Krucker, Sam; hide

    2016-01-01

    We have developed a fine-pitch hard X-ray (HXR) detector using a cadmium telluride (CdTe) semiconductor for imaging and spectroscopy for the second launch of the Focusing Optics Solar X-ray Imager (FOXSI). FOXSI is a rocket experiment to perform high sensitivity HXR observations from 4 to 15 keV using the new technique of HXR focusing optics. The focal plane detector requires less than 100 micrometers position resolution (to take advantage of the angular resolution of the optics) and approximately equals 1 keV energy resolution (full width at half maximum (FWHM)) for spectroscopy down to 4 keV, with moderate cooling (greater than -30 C). Double-sided silicon strip detectors were used for the first FOXSI flight in 2012 to meet these criteria. To improve the detectors' efficiency (66% at 15 keV for the silicon detectors) and position resolution of 75 micrometers for the second launch, we fabricated double-sided CdTe strip detectors with a position resolution of 60 micrometers and almost 100% efficiency for the FOXSI energy range. The sensitive area is 7.67 mm x 7.67 mm, corresponding to the field of view of 791'' x 791''. An energy resolution of 1 keV (FWHM) and low-energy threshold of approximately equals 4 keV were achieved in laboratory calibrations. The second launch of FOXSI was performed on 11 December 2014, and images from the Sun were successfully obtained with the CdTe detector. Therefore, we successfully demonstrated the detector concept and the usefulness of this technique for future HXR observations of the Sun.

  5. BAT AGN Spectroscopic Survey - IV: Near-Infrared Coronal Lines, Hidden Broad Lines, and Correlation with Hard X-ray Emission

    Science.gov (United States)

    Lamperti, Isabella; Koss, Michael; Trakhtenbrot, Benny; Schawinski, Kevin; Ricci, Claudio; Oh, Kyuseok; Landt, Hermine; Riffel, Rogério; Rodríguez-Ardila, Alberto; Gehrels, Neil; Harrison, Fiona; Masetti, Nicola; Mushotzky, Richard; Treister, Ezequiel; Ueda, Yoshihiro; Veilleux, Sylvain

    2017-05-01

    We provide a comprehensive census of the near-infrared (NIR, 0.8-2.4 μm) spectroscopic properties of 102 nearby (z X-ray band (14-195 keV) from the Swift-Burst Alert Telescope survey. With the launch of the James Webb Space Telescope, this regime is of increasing importance for dusty and obscured AGN surveys. We measure black hole masses in 68 per cent (69/102) of the sample using broad emission lines (34/102) and/or the velocity dispersion of the Ca II triplet or the CO band-heads (46/102). We find that emission-line diagnostics in the NIR are ineffective at identifying bright, nearby AGN galaxies because [Fe II] 1.257 μm/Paβ and H2 2.12 μm/Brγ identify only 25 per cent (25/102) as AGN with significant overlap with star-forming galaxies and only 20 per cent of Seyfert 2 have detected coronal lines (6/30). We measure the coronal line emission in Seyfert 2 to be weaker than in Seyfert 1 of the same bolometric luminosity suggesting obscuration by the nuclear torus. We find that the correlation between the hard X-ray and the [Si VI] coronal line luminosity is significantly better than with the [O III] λ5007 luminosity. Finally, we find 3/29 galaxies (10 per cent) that are optically classified as Seyfert 2 show broad emission lines in the NIR. These AGN have the lowest levels of obscuration among the Seyfert 2s in our sample (log NH < 22.43 cm-2), and all show signs of galaxy-scale interactions or mergers suggesting that the optical broad emission lines are obscured by host galaxy dust.

  6. Soft X-ray focusing Telescope aboard AstroSat

    DEFF Research Database (Denmark)

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

    2017-01-01

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

  7. Hard X-ray detection of the black hole candidates 4U 1630-47 and IGR J17091-3624 up to 200 keV with INTEGRAL

    DEFF Research Database (Denmark)

    Bodaghee, A.; Kuulkers, E.; Tomsick, J. A.

    2012-01-01

    During monitoring observations of the Norma and Inner Perseus Arms (rev. 1209: 2012 Sept. 6 from 18:18:23 to 22:00:21 UTC), INTEGRAL-ISGRI revealed that the accreting black hole candidates 4U 1630-47 and IGR J17091-3624 have brightened in the hard X-rays. Mosaic images consisting of 12.6 ks worth...

  8. Hard X-ray spectral and timing properties of IGR J17454-2919 consistent with a black hole in the hard state

    DEFF Research Database (Denmark)

    Tendulkar, Shriharsh P.; Bachetti, Matteo; Tomsick, J.

    2014-01-01

    frequencies. The Lorentzian has a width of 2 Hz and a fractional rms of 25+/-3%. The hard power-law index, the high energy of the cutoff, and the level of variability all are consistent with properties expected for an accreting black hole in the hard state. While we cannot completely rule out the possibility...... of a low magnetic field neutron star, a black hole is more likely....

  9. Hard and soft X-ray spectroscopy of Sm-based heavy-fermion compounds SmFe{sub 4} P{sub 12} and SmOs{sub 4} Sb{sub 12}

    Energy Technology Data Exchange (ETDEWEB)

    Yamasaki, A. [Department of Physics, Faculty of Science and Engineering, Konan University, Kobe 658-8501 (Japan)], E-mail: yamasaki@konan-u.ac.jp; Imada, S.; Higashimichi, H.; Fujiwara, H.; Saita, T.; Miyamachi, T.; Sekiyama, A. [Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531 (Japan); Sugawara, H. [Graduate School of Human and Natural Environment Science, University of Tokushima, Tokushima 770-8502 (Japan); Kikuchi, D.; Sato, H. [Graduate School of Science, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397 (Japan); Higashiya, A. [RIKEN, Mikazuki, Sayo, Hyogo 679-5148 (Japan); Yabashi, M. [Japan Synchrotron Research Institute, Mikazuki, Sayo, Hyogo 679-5198 (Japan); Tamasaku, K.; Miwa, D.; Ishikawa, T. [RIKEN, Mikazuki, Sayo, Hyogo 679-5148 (Japan); Suga, S. [Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531 (Japan)

    2007-05-15

    We have carried out soft and hard X-ray spectroscopy of Sm-based filled skutterudites SmFe{sub 4} P{sub 12} and SmOs{sub 4} Sb{sub 12}. Sm 3d-4f resonant photoemission and Sm 3d-4f X-ray absorption spectra suggest that SmOs{sub 4} Sb{sub 12} has much more strongly mixed Sm valence state than SmFe{sub 4} P{sub 12} in the bulk. On the other hand, the Sm trivalent state is dominant on the surface of SmOs{sub 4} Sb{sub 12}.

  10. Direct observation of bias-dependence potential distribution in metal/HfO{sub 2} gate stack structures by hard x-ray photoelectron spectroscopy under device operation

    Energy Technology Data Exchange (ETDEWEB)

    Yamashita, Y. [National Institute for Materials Science, Advanced Electric Materials Center, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); National Institute for Materials Science, NIMS Beamline Station at SPring-8, 1-1-1 Kôto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Yoshikawa, H.; Kobayashi, K. [National Institute for Materials Science, NIMS Beamline Station at SPring-8, 1-1-1 Kôto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Chikyo, T. [National Institute for Materials Science, Advanced Electric Materials Center, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)

    2014-01-28

    Although gate stack structures with high-k materials have been extensively investigated, there are some issues to be solved for the formation of high quality gate stack structures. In the present study, we employed hard x-ray photoelectron spectroscopy in operating devices. This method allows us to investigate bias dependent electronic states, while keeping device structures intact. Using this method, we have investigated electronic states and potential distribution in gate metal/HfO{sub 2} gate stack structures under device operation. Analysis of the core levels shifts as a function of the bias voltage indicated that a potential drop occurred at the Pt/HfO{sub 2} interface for a Pt/HfO{sub 2} gate structure, while a potential gradient was not observed at the Ru/HfO{sub 2} interface for a Ru/HfO{sub 2} gate structure. Angle resolved photoelectron spectroscopy revealed that a thicker SiO{sub 2} layer was formed at the Pt/HfO{sub 2} interface, indicating that the origin of potential drop at Pt/HfO{sub 2} interface is formation of the thick SiO{sub 2} layer at the interface. The formation of the thick SiO{sub 2} layer at the metal/high-k interface might concern the Fermi level pinning, which is observed in metal/high-k gate stack structures.

  11. Determination of the surface band bending in InxGa1−xN films by hard x-ray photoemission spectroscopy

    Directory of Open Access Journals (Sweden)

    Mickael Lozac'h, Shigenori Ueda, Shitao Liu, Hideki Yoshikawa, Sang Liwen, Xinqiang Wang, Bo Shen, Kazuaki Sakoda, Keisuke Kobayashi and Masatomo Sumiya

    2013-01-01

    Full Text Available Core-level and valence band spectra of InxGa1−xN films were measured using hard x-ray photoemission spectroscopy (HX-PES. Fine structure, caused by the coupling of the localized Ga 3d and In 4d with N 2s states, was experimentally observed in the films. Because of the large detection depth of HX-PES (~20 nm, the spectra contain both surface and bulk information due to the surface band bending. The InxGa1−xN films (x = 0–0.21 exhibited upward surface band bending, and the valence band maximum was shifted to lower binding energy when the mole fraction of InN was increased. On the other hand, downward surface band bending was confirmed for an InN film with low carrier density despite its n-type conduction. Although the Fermi level (EF near the surface of the InN film was detected inside the conduction band as reported previously, it can be concluded that EF in the bulk of the film must be located in the band gap below the conduction band minimum.

  12. Quantitative study of the f-occupation in CeMIn{sub 5} and other cerium compounds with hard X-ray core level photo emission

    Energy Technology Data Exchange (ETDEWEB)

    Sundermann, Martin; Strigari, Fabio; Willers, Thomas; Severing, Andrea [University of Cologne, Cologne (Germany); Weinen, Jonas; Tjeng, Liu Hao [Max Planck Institute for Chemical Physics of Solids, Dresden (Germany); Liao, Yen-Fa; Tsuei, Ku-Ding [National Synchrotron Radiation Research Center, Hsinchu (China); Bauer, Eric D.; Sarrao, John L.; Thompson, Joe D. [Los Alamos National Laboratory, Los Alamos (United States); Lejay, Pascal [Institut NEEL, CNRS, Grenoble (France); Tanaka, Arata [Hiroshima University, Higashi-Hiroshima (Japan)

    2016-07-01

    Bulk-sensitive hard X-ray photoelectron spectroscopy (HAXPES) data of the Ce3d core levels of the CeMIn{sub 5} family with M = Co, Rh, and Ir will be presented. The data analysis combines a full multiplet and configuration interaction model so that the strong plasmons intensities can be corrected for. This way spectral f{sup n} weights can be extracted and the configuration interaction model yields quantitative values for the initial state f-occupation of the CeMIn{sub 5}. The results are compared with HAXPES data of other heavy Ce compounds of very different hybridization strength. A systematic decrease of the hybridization strength V{sub eff} from CePd{sub 3} to CeRh{sub 3}B{sub 2} to CeRu{sub 2}Si{sub 2} is observed, and it is smallest for the three CeMIn{sub 5} compounds. The f-occupation increases in the same sequence and is close to one for the CeMIn{sub 5} family.

  13. Hard x-ray photoemission study of Yb1-x Zr x B12: the effects of electron doping on the Kondo insulator YbB12

    Science.gov (United States)

    Rousuli, A.; Sato, H.; Iga, F.; Hayashi, K.; Ishii, K.; Wada, T.; Nagasaki, T.; Mimura, K.; Anzai, H.; Ichiki, K.; Ueda, S.; Kondo, A.; Kindo, K.; Takabatake, T.; Shimada, K.; Namatame, H.; Taniguchi, M.

    2017-07-01

    We have carried out hard x-ray photoemission spectroscopy (HAXPES) of Yb1-x Zr x B12 (0≤slant x≤slant 0.875 ) to study the effects of electron doping on the Kondo insulator YbB12. The Yb valences of Yb1-x Zr x B12 at 300 K estimated from the Yb 3d HAXPES spectra decreased after substituting Yb with Zr from 2.93 for YbB12 to 2.83 for Yb0.125Zr0.875B12. A temperature dependent valence decrease was found upon cooling for all doping concentrations. We found peak shifts of the B 1s and Zr 3d5/2, and Yb3+ 4f spectra toward the deeper binding-energy with increasing Zr concentration, which indicates a shift of the Fermi level to the higher energy and that of the Yb 4f hole level close to the Fermi level, respectively, due to electron doping. These results qualitatively show the enhanced hybridization between the Yb 4f and conduction-band states with Zr substitution, consistent with magnetic susceptibility measurements.

  14. A low-noise 64-channel front-end readout ASIC for CdZnTe detectors aimed to hard X-ray imaging systems

    Energy Technology Data Exchange (ETDEWEB)

    Gan, B.; Wei, T.; Gao, W., E-mail: gaowu@nwpu.edu.cn; Liu, H.; Hu, Y.

    2016-04-21

    In this paper, we report on the recent development of a 64-channel low-noise front-end readout ASIC for CdZnTe detectors aimed to hard X-ray imaging systems. The readout channel is comprised of a charge sensitive amplifier, a leakage current compensation circuit, a CR-RC shaper, two S–K filters, an inverse proportional amplifier, a peak-detect-and-hold circuit, a discriminator and trigger logic, a time sequence control circuit and a driving buffer. The readout ASIC is implemented in TSMC 0.35 μm mixed-signal CMOS technology, the die size of the prototype chip is 2.7 mm×8.0 mm. The overall gain of the readout channel is 200 mV/fC, the power consumption is less than 8 mW/channel, the linearity error is less than 1%, the inconsistency among the channels is less than 2.86%, and the equivalent noise charge of a typical channel is 66 e{sup −} at zero farad plus 14 e{sup −} per picofarad. By connecting this readout ASIC to an 8×8 pixel CdZnTe detector, we obtained an energy spectrum, the energy resolution of which is 4.5% at the 59.5 keV line of {sup 241}Am source.

  15. Multiwavelength Study of Quiescent States of Mrk 421 with Unprecedented Hard X-Ray Coverage Provided by NuSTAR in 2013

    CERN Document Server

    Baloković, M.; Madejski, G.; Furniss, A.; Chiang, J.; Ajello, M.; Alexander, D.M.; Barret, D.; Blandford, R.; Boggs, S.E.; Christensen, F.E.; Craig, W.W.; Forster, K.; Giommi, P.; Grefenstette, B.W.; Hailey, C.J.; Harrison, F.A.; Hornstrup, A.; Kitaguchi, T.; Koglin, J.E.; Madsen, K.K.; Mao, P.H.; Miyasaka, H.; Mori, K.; Perri, M.; Pivovaroff, M.J.; Puccetti, S.; Rana, V.; Stern, D.; Tagliaferri, G.; Urry, C.M.; Westergaard, N.J.; Zhang, W.W.; Zoglauer, A.; Archambault, S.; Archer, A.A.; Barnacka, A.; Benbow, W.; Bird, R.; Buckley, J.; Bugaev, V.; Cerruti, M.; Chen, X.; Ciupik, L.; Connolly, M.P.; Cui, W.; Dickinson, H.J.; Dumm, J.; Eisch, J.D.; Falcone, A.; Feng, Q.; Finley, J.P.; Fleischhack, H.; Fortson, L.; Griffin, S.; Griffiths, S.T.; Grube, J.; Gyuk, G.; Huetten, M.; Haakansson, N.; Holder, J.; Humensky, T.B.; Johnson, C.A.; Kaaret, P.; Kertzman, M.; Khassen, Y.; Kieda, D.; Krause, M.; Krennrich, F.; Lang, M.J.; Maier, G.; McArthur, S.; Meagher, K.; Moriarty, P.; Nelson, T.; Nieto, D.; Ong, R.A.; Park, N.; Pohl, M.; Popkow, A.; Pueschel, E.; Reynolds, P.T.; Richards, G.T.; Roache, E.; Santander, M.; Sembroski, G.H.; Shahinyan, K.; Smith, A.W.; Staszak, D.; Telezhinsky, I.; Todd, N.W.; Tucci, J.V.; Tyler, J.; Vincent, S.; Weinstein, A.; Wilhelm, A.; Williams, D.A.; Zitzer, B.; Ahnen, M.L.; Ansoldi, S.; Antonelli, L.A.; Antoranz, P.; Babic, A.; Banerjee, B.; Bangale, P.; Barres de Almeida, U.; Barrio, J.; Becerra González, J.; Bednarek, W.; Bernardini, E.; Biasuzzi, B.; Biland, A.; Blanch, O.; Bonnefoy, S.; Bonnoli, G.; Borracci, F.; Bretz, T.; Carmona, E.; Carosi, A.; Chatterjee, A.; Clavero, R.; Colin, P.; Colombo, E.; Contreras, J.L.; Cortina, J.; Covino, S.; Da Vela, P.; Dazzi, F.; de Angelis, A.; De Lotto, B.; Wilhelmi, E. D. de Oña; Delgado Mendez, C.; Di Pierro, F.; Dominis Prester, D.; Dorner, D.; Doro, M.; Einecke, S.; Elsaesser, D.; Fernández-Barral, A.; Fidalgo, D.; Fonseca, M.V.; Font, L.; Frantzen, K.; Fruck, C.; Galindo, D.; López, R. J. García; Garczarczyk, M.; Garrido Terrats, D.; Gaug, M.; Giammaria, P.; Eisenacher, D.; Godinović, N.; González Muñoz, A.; Guberman, D.; Hahn, A.; Hanabata, Y.; Hayashida, M.; Herrera, J.; Hose, J.; Hrupec, D.; Hughes, G.; Idec, W.; Kodani, K.; Konno, Y.; Kubo, H.; Kushida, J.; La Barbera, A.; Lelas, D.; Lindfors, E.; Lombardi, S.; Longo, F.; López, M.; López-Coto, R.; López-Oramas, A.; Lorenz, E.; Majumdar, P.; Makariev, M.; Mallot, K.; Maneva, G.; Manganaro, M.; Mannheim, K.; Maraschi, L.; Marcote, B.; Mariotti, M.; Martínez, M.; Mazin, D.; Menzel, U.; Miranda, J.M.; Mirzoyan, R.; Moralejo, A.; Moretti, E.; Nakajima, D.; Neustroev, V.; Niedzwiecki, A.; Nievas-Rosillo, M.; Nilsson, K.; Nishijima, K.; Noda, K.; Orito, R.; Overkemping, A.; Paiano, S.; Palacio, S.; Palatiello, M.; Paoletti, R.; Paredes, J.M.; Paredes-Fortuny, X.; Persic, M.; Poutanen, J.; Prada Moroni, P. G.; Prandini, E.; Puljak, I.; Rhode, W.; Ribó, M.; Rico, J.; Garcia, J. Rodriguez; Saito, T.; Satalecka, K.; Scapin, V.; Schultz, C.; Schweizer, T.; Shore, S.N.; Sillanpää, A.; Sitarek, J.; Snidaric, I.; Sobczynska, D.; Stamerra, A.; Steinbring, T.; Strzys, M.; Takalo, L.O.; Takami, H.; Tavecchio, F.; Temnikov, P.; Terzić, T.; Tescaro, D.; Teshima, M.; Thaele, J.; Torres, D.F.; Toyama, T.; Treves, A.; Verguilov, V.; Vovk, I.; Ward, J.E.; Will, M.; Wu, M.H.; Zanin, R.; Perkins, J.; Verrecchia, F.; Leto, C.; Böttcher, M.; Villata, M.; Raiteri, C.M.; Acosta-Pulido, J.A.; Bachev, R.; Berdyugin, A.; Blinov, D.A.; Carnerero, M.I.; Chen, W.P.; Chinchilla, P.; Damljanovic, G.; Eswaraiah, C.; Grishina, T.S.; Ibryamov, S.; Jordan, B.; Jorstad, S.G.; Joshi, M.; Kopatskaya, E.N.; Kurtanidze, O.M.; Kurtanidze, S.O.; Larionova, E.G.; Larionova, L.V.; Larionov, V.M.; Latev, G.; Lin, H.C.; Marscher, A.P.; Mokrushina, A.A.; Morozova, D.A.; Nikolashvili, M.G.; Semkov, E.; Strigachev, A.; Troitskaya, Yu. V.; Troitsky, I.S.; Vince, O.; Barnes, J.; Güver, T.; Moody, J.W.; Sadun, A.C.; Sun, S.; Hovatta, T.; Richards, J.L.; Max-Moerbeck, W.; Readhead, A.C.; Lähteenmäki, A.; Tornikoski, M.; Tammi, J.; Ramakrishnan, V.; Reinthal, R.; Angelakis, E.; Fuhrmann, L.; Myserlis, I.; Karamanavis, V.; Sievers, A.; Ungerechts, H.; Zensus, J.A.

    2016-01-01

    We present coordinated multiwavelength observations of the bright, nearby BL Lac object Mrk 421 taken in 2013 January-March, involving GASP-WEBT, Swift, NuSTAR, Fermi-LAT, MAGIC, VERITAS, and other collaborations and instruments, providing data from radio to very-high-energy (VHE) gamma-ray bands. NuSTAR yielded previously unattainable sensitivity in the 3-79 keV range, revealing that the spectrum softens when the source is dimmer until the X-ray spectral shape saturates into a steep power law with a photon index of approximately 3, with no evidence for an exponential cutoff or additional hard components up to about 80 keV. For the first time, we observed both the synchrotron and the inverse-Compton peaks of the spectral energy distribution (SED) simultaneously shifted to frequencies below the typical quiescent state by an order of magnitude. The fractional variability as a function of photon energy shows a double-bump structure which relates to the two bumps of the broadband SED. In each bump, the variabilit...

  16. SN 2010j1: Optical to Hard X-Ray Observations Reveal an Explosion Embedded in a Ten Solar Mass Cocoon

    Science.gov (United States)

    Ofek, Eran; Zoglauer, Andreas; Boggs, Steven E.; Barriere, Nicolas M.; Reynolds, Stephen P.; Fryer, Chris L.; Harrison, Fiona A.; Cenko, S. Bradley; Kulkarni, Shrinivas R.; Zhang, William W.; hide

    2014-01-01

    Some supernovae (SNe) may be powered by the interaction of the SN ejecta with a large amount of circumstellar matter (CSM). However, quantitative estimates of the CSM mass around such SNe are missing when the CSM material is optically thick. Specifically, current estimators are sensitive to uncertainties regarding the CSM density profile and the ejecta velocity. Here we outline a method to measure the mass of the optically thick CSM around such SNe. We present new visible-light and X-ray observations of SN 2010jl (PTF 10aaxf), including the first detection of an SN in the hard X-ray band using NuSTAR. The total radiated luminosity of SN 2010jl is extreme atleast 9 1050 erg. By modeling the visible-light data, we robustly show that the mass of the circumstellar material within 1016 cm of the progenitor of SN 2010jl was in excess of 10M_. This mass was likely ejected tens of years prior to the SN explosion. Our modeling suggests that the shock velocity during shock breakout was 6000 km s1, decelerating to 2600 km s1 about 2 yr after maximum light. Furthermore, our late-time NuSTAR and XMM spectra of the SN presumably provide the first direct measurement of SN shock velocity 2 yr after the SN maximum light measured to be in the range of 2000-4500 km s1 if the ions and electrons are in equilibrium, and_2000 km s1 if they are not in equilibrium. This measurement is in agreement with the shock velocity predicted by our modeling of the visible-light data. Our observations also show that the average radial density distribution of the CSM roughly follows an r2 law. A possible explanation for the _10M_ of CSM and the wind-like profile is that they are the result of multiple pulsational pair instability events prior to the SN explosion, separated from each other by years.

  17. Chest X-Ray

    Medline Plus

    Full Text Available ... the most commonly performed x-ray exams and use a very small dose of ionizing radiation to ... to your health. While a chest x-ray use a tiny dose of ionizing radiation, the benefit ...

  18. Developing fine-pixel CdTe detectors for the next generation of high-resolution hard x-ray telescopes

    Science.gov (United States)

    Christe, Steven

    Over the past decade, the NASA Marshall Space Flight Center (MSFC) has been improving the angular resolution of hard X-ray (HXR; 20 "70 keV) optics to the point that we now routinely manufacture optics modules with an angular resolution of 20 arcsec Half Power Diameter (HDP), almost three times the performance of NuSTAR optics (Ramsey et al. 2013; Gubarev et al. 2013a; Atkins et al. 2013). New techniques are currently being developed to provide even higher angular resolution. High angular resolution HXR optics require detectors with a large number of fine pixels in order to adequately sample the telescope point spread function (PSF) over the entire field of view. Excessively over-sampling the PSF will increase readout noise and require more processing with no appreciable increase in image quality. An appropriate level of over-sampling is to have 3 pixels within the HPD. For the HERO mirrors, where the HPD is 26 arcsec over a 6-m focal length converts to 750 μm, the optimum pixel size is around 250 μm. At a 10-m focal length these detectors can support a 16 arcsec HPD. Of course, the detectors must also have high efficiency in the HXR region, good energy resolution, low background, low power requirements, and low sensitivity to radiation damage (Ramsey 2001). The ability to handle high counting rates is also desirable for efficient calibration. A collaboration between Goddard Space Flight Center (GSFC), MSFC, and Rutherford Appleton Laboratory (RAL) in the UK is developing precisely such detectors under an ongoing, funded APRA program (FY2015 to FY2017). The detectors use the RALdeveloped Application Specific Integrated Circuit (ASIC) dubbed HEXITEC, for High Energy X-Ray Imaging Technology. These HEXITEC ASICs can be bonded to 1- or 2- mm-thick Cadmium Telluride (CdTe) or Cadmium-Zinc-Telluride (CZT) to create a fine (250 μm pitch) HXR detector (Jones et al. 2009; Seller et al. 2011). The objectives of this funded effort are to develop and test a HEXITEC

  19. Hand x-ray

    Science.gov (United States)

    X-ray - hand ... A hand x-ray is taken in a hospital radiology department or your health care provider's office by an ... technician. You will be asked to place your hand on the x-ray table, and keep it ...

  20. X-Ray

    Science.gov (United States)

    ... show up on chest X-rays. Breast cancer. Mammography is a special type of X-ray test used to examine breast tissue. Enlarged heart. This sign of congestive heart failure shows up clearly on X-rays. Blocked blood vessels. Injecting a contrast material that contains iodine can help highlight sections ...

  1. X-ray microdiffraction of biominerals.

    Science.gov (United States)

    Tamura, Nobumichi; Gilbert, Pupa U P A

    2013-01-01

    Biominerals have complex and heterogeneous architectures, hence diffraction experiments with spatial resolutions between 500 nm and 10 μm are extremely useful to characterize them. X-ray beams in this size range are now routinely produced at many synchrotrons. This chapter provides a review of the different hard X-ray diffraction and scattering techniques, used in conjunction with efficient, state-of-the-art X-ray focusing optics. These include monochromatic X-ray microdiffraction, polychromatic (Laue) X-ray microdiffraction, and microbeam small-angle X-ray scattering. We present some of the most relevant discoveries made in the field of biomineralization using these approaches. © 2013 Elsevier Inc. All rights reserved.

  2. Comparing natural and artificial carious lesions in human crowns by means of conventional hard x-ray micro-tomography and two-dimensional x-ray scattering with synchrotron radiation

    Science.gov (United States)

    Botta, Lea Maria; White, Shane N.; Deyhle, Hans; Dziadowiec, Iwona; Schulz, Georg; Thalmann, Peter; Müller, Bert

    2016-10-01

    Dental caries, one of the most prevalent infectious bacterial diseases in the world, is caused by specific types of acid-producing bacteria. Caries is a disease continuum resulting from the earliest loss of ions from apatite crystals through gross cavitation. Enamel dissolution starts when the pH-value drops below 5.5. Neutralizing the pH-value in the oral cavity opposes the process of demineralization, and so caries lesions occur in a dynamic cyclic de-mineralizing/remineralizing environment. Unfortunately, biomimetic regeneration of cavitated enamel is not yet possible, although remineralization of small carious lesions occurs under optimal conditions. Therefore, the development of methods that can regenerate carious lesions, and subsequently recover and retain teeth, is highly desirable. For the present proceedings we analyzed one naturally occurring sub-surface and one artificially produced lesion. For the characterization of artificial and natural lesions micro computed tomography is the method of choice when looking to determine three-dimensional mineral distribution and to quantify the degree of mineralization. In this pilot study we elucidate that the de-mineralized enamel in natural and artificially induced lesions shows comparable X-ray attenuation behavior, thereby implying that the study protocol employed herein seems to be appropriate. Once we know that the lesions are comparable, a series of well-reproducible in vitro experiments on enamel regeneration could be performed. In order to quantify further lesion morphology, the anisotropy of the enamel's nanostructure can be characterized by using spatially resolved, small-angle X-ray scattering. We wanted to demonstrate that the artificially induced defect fittingly resembles the natural carious lesion.

  3. 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

  4. Three-dimensional Forward-fit Modeling of the Hard X-Ray and Microwave Emissions of the 2015 June 22 M6.5 Flare

    Science.gov (United States)

    Kuroda, Natsuha; Gary, Dale E.; Wang, Haimin; Fleishman, Gregory D.; Nita, Gelu M.; Jing, Ju

    2018-01-01

    The well-established notion of a “common population” of the accelerated electrons simultaneously producing the hard X-ray (HXR) and microwave (MW) emission during the flare impulsive phase has been challenged by some studies reporting the discrepancies between the HXR-inferred and MW-inferred electron energy spectra. The traditional methods of spectral inversion have some problems that can be mainly attributed to the unrealistic and oversimplified treatment of the flare emission. To properly address this problem, we use a nonlinear force-free field (NLFFF) model extrapolated from an observed photospheric magnetogram as input to the three-dimensional, multiwavelength modeling platform GX Simulator and create a unified electron population model that can simultaneously reproduce the observed HXR and MW observations. We model the end of the impulsive phase of the 2015 June 22 M6.5 flare and constrain the modeled electron spatial and energy parameters using observations made by the highest-resolving instruments currently available in two wavelengths, the Reuven Ramaty High Energy Solar Spectroscopic Imager for HXR and the Expanded Owens Valley Solar Array for MW. Our results suggest that the HXR-emitting electron population model fits the standard flare model with a broken power-law spectrum ({E}{break}∼ 200 keV) that simultaneously produces the HXR footpoint emission and the MW high-frequency emission. The model also includes an “HXR-invisible” population of nonthermal electrons that are trapped in a large volume of magnetic field above the HXR-emitting loops, which is observable by its gyrosynchrotron radiation emitting mainly in the MW low-frequency range.

  5. Measurement of valence-band offset at native oxide/BaSi{sub 2} interfaces by hard x-ray photoelectron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Takabe, Ryota; Du, Weijie; Takeuchi, Hiroki; Toko, Kaoru [Institute of Applied Physics, University of Tsukuba, Tsukuba, Ibaraki 305-8573 (Japan); Ito, Keita [Institute of Applied Physics, University of Tsukuba, Tsukuba, Ibaraki 305-8573 (Japan); Japan Society for the Promotion of Science (JSPS), Chiyoda, Tokyo 102-0083 (Japan); Department of Electronic Engineering, Graduate School of Engineering, Tohoku University, Sendai 980-8579 (Japan); Ueda, Shigenori [Synchrotron X-ray Station at SPring-8, National Institute for Materials Science (NIMS), Hyogo 679-5148 (Japan); Quantum Beam Unit, NIMS, Tsukuba, Ibaraki 305-0047 (Japan); Kimura, Akio [Graduate School of Science, Hiroshima University, Higashi-hiroshima 739-8526 (Japan); Suemasu, Takashi [Institute of Applied Physics, University of Tsukuba, Tsukuba, Ibaraki 305-8573 (Japan); Japan Science and Technology Agency, CREST, Tokyo 102-0075 (Japan)

    2016-01-14

    Undoped n-type BaSi{sub 2} films were grown on Si(111) by molecular beam epitaxy, and the valence band (VB) offset at the interface between the BaSi{sub 2} and its native oxide was measured by hard x-ray photoelectron spectroscopy (HAXPES) at room temperature. HAXPES enabled us to investigate the electronic states of the buried BaSi{sub 2} layer non-destructively thanks to its large analysis depth. We performed the depth-analysis by varying the take-off angle (TOA) of photoelectrons as 15°, 30°, and 90° with respect to the sample surface and succeeded to obtain the VB spectra of the BaSi{sub 2} and the native oxide separately. The VB maximum was located at −1.0 eV from the Fermi energy for the BaSi{sub 2} and −4.9 eV for the native oxide. We found that the band bending did not occur near the native oxide/BaSi{sub 2} interface. This result was clarified by the fact that the core-level emission peaks did not shift regardless of TOA (i.e., analysis depth). Thus, the barrier height of the native oxide for the minority-carriers in the undoped n-BaSi{sub 2} (holes) was determined to be 3.9 eV. No band bending in the BaSi{sub 2} close to the interface also suggests that the large minority-carrier lifetime in undoped n-BaSi{sub 2} films capped with native oxide is attributed not to the band bending in the BaSi{sub 2}, which pushes away photogenerated minority carriers from the defective surface region, but to the decrease of defective states by the native oxide.

  6. A Hard X-ray Study of a Manganese-Terpyridine Dimer Catalyst in a Chromium-based Metal Organic Framework - Oral Presentation

    Energy Technology Data Exchange (ETDEWEB)

    Ramsey, Alexandra [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2015-08-25

    Cleaner forms of energy are needed, and H2 produced from water spliFng is a possible source. However, a robust catalyst is necessary to carry out the water oxidaKon reacKon. Plants uKlize Photosystem II to catalyze water oxidaKon as a part of photosynthesis, and many syntheKc water oxidaKon catalysts use Photosystem II as a model. In this study, the catalyst of interest was [(terpy)Mn(μ-O)2Mn(terpy)]3+ (MnTD), which was synthesized in a chromium-based Metal Organic Framework (MOF) to avoid degradaKon of MnTD molecules. Hard X-ray powder diffracKon was the primary method of analysis. The diffracKon data was used to detect the presence of MOF in samples at different catalyKc stages, and laFce parameters were assigned to the samples containing MOF. Fourier maps were constructed to determine the contents of the MOF as preliminary studies suggested that MnTD may not be present. Results showed that MOF is present before catalysis occurs, but disappears in the iniKal stages of catalysis. Changes in the MOF’s laFce parameters suggest aWracKve interacKons between the MOF and catalyst; these interacKons may lead to the observed MOF degradaKon. Fourier maps also reveal limited, if any, amounts of MnTD in the system. Molecular manganese oxide may be the source of the high rate of water oxidaKon catalysis in the studied system.

  7. Microscopic study of dental hard tissues in primary teeth with Dentinogenesis Imperfecta Type II: Correlation of 3D imaging using X-ray microtomography and polarising microscopy.

    Science.gov (United States)

    Davis, Graham R; Fearne, Janice M; Sabel, Nina; Norén, Jörgen G

    2015-07-01

    The aim of this study was to examine the histological appearance of dental hard tissues in primary teeth from children with DI using conventional polarised light microscopy and correlate that with 3D imaging using X-ray microtomograpy (XMT) to gain a further understanding of the dentine structure of teeth diagnosed with dentinogenesis imperfecta. Undecalcified sections of primary teeth from patients diagnosed with Dentinogenesis Imperfecta Type II were examined using polarised light microscopy. XMT was employed for 3D-imaging and analysis of the dentine. The polarised light microscopy and XMT revealed tubular structures in the dentine seen as vacuoles coinciding with the path of normal dentinal tubules but not continuous tubules. The size of the tubules was close to that of capillaries. The largest tubular structures had a direction corresponding to where the pulp tissue would have been located during primary dentine formation. The dysfunctional mineralisation of the dentine and obliteration of the pulp evidently leaves blood vessels in the dentine which have in the main been tied off and, in the undecalcified sections, appear as vacuoles. Although from radiographs, the pulp in teeth affected by Dentinogenesis Imperfect type II appears to be completely obliterated, a network of interconnected vessels may remain. The presence of large dentinal tubules and blood vessels, or the remnants of blood vessels, could provide a pathway for bacteria from the oral cavity. This might account for why some of these teeth develop periapical abscesses in spite of apparently having no pulp. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Hard X-ray Standing-Wave Photoelectron Spectroscopy Study of Cobalt-Iron-Boron/Magnesium Oxide Magnetic Tunnel Junction Multilayers

    Science.gov (United States)

    Greer, Albert Anthony

    As one key aspect of the area of spin-based electronics or spintronics, the magnetic tunnel junction (MTJ) holds special promise for magnetic memory, and possibly also logic devices. In an MTJ, two ferromagnetic layers are separated by a very thin nonmagnetic insulating layer and the key effect is based on the spin-dependent tunneling of electrons through the insulating layer and is called tunnel magnetoresistance (TMR). Resistance is lower when the two ferromagnetic layers are oriented parallel to one another, and higher when they are anti-parallel. Recent work reveals that MTJs with a Ta/CoFeB/MgO/CoFeB/Ta structure show three optimal characteristics: 1) high thermal stability on the nanoscale, 2) a high TMR ratio, and 3) low switching current for current-induced switching of magnetization across the interface. Studies suggest that B diffusion from the initially amorphous CoFeB layer into the MgO causes CoFeB crystallization such that TMR-increasing perpendicular anisotropy (PMA) arises at the MgO/CoFeB interface. Furthermore, the TMR ratio is likewise regulated by B diffusion into the Ta layer. Scientists are currently exploring the structure/properties relationships of these buried interfaces in magnetic nanostructures. One effective method for probing the composition, structure, and properties of buried layers is the newly-developed technique of standing-wave, hard x-ray photoelectron spectroscopy or SW-HAXPES. In this method, a standing wave is generated by Bragg reflection from a synthetic multilayer mirror upon which the sample is deposited. This standing wave can be scanned vertically through the sample by varying the incidence angle around the Bragg angle, giving a rocking curve (RC) scan. Using SW-HAXPES, we studied the B distribution in a Ta/Co0.2Fe0.6B0.2/MgO sample. We obtained hard x-ray standing-wave data, as well as conventional variable takeoff angle XPS (angle-resolved XPS or ARXPS) data at SPring-8 in Japan, as well as complimentary soft x-ray

  9. X-Ray Polarimetry

    OpenAIRE

    Kaaret, Philip

    2014-01-01

    We review the basic principles of X-ray polarimetry and current detector technologies based on the photoelectric effect, Bragg reflection, and Compton scattering. Recent technological advances in high-spatial-resolution gas-filled X-ray detectors have enabled efficient polarimeters exploiting the photoelectric effect that hold great scientific promise for X-ray polarimetry in the 2-10 keV band. Advances in the fabrication of multilayer optics have made feasible the construction of broad-band ...

  10. Multiwavelength study of quiescent states of MRK 421 with unprecedented hard x-ray coverage provided by NuSTAR in 2013

    DEFF Research Database (Denmark)

    Baloković, M.; Paneque, D.; Madejski, G.

    2016-01-01

    that relates to the two bumps of the broadband SED. In each bump, the variability increases with energy, which, in the framework of the synchrotron self-Compton model, implies that the electrons with higher energies are more variable. The measured multi band variability, the significant X......-ray-to-VHE correlation down to some of the lowest fluxes ever observed in both bands, the lack of correlation between optical/UV and X-ray flux, the low degree of polarization and its significant (random) variations, the short estimated electron cooling time, and the significantly longer variability timescale observed...

  11. Time-dependent wave front propagation simulation of a hard x-ray split-and-delay unit: Towards a measurement of the temporal coherence properties of x-ray free electron lasers

    Directory of Open Access Journals (Sweden)

    S. Roling

    2014-11-01

    Full Text Available For the European x-ray free electron laser (XFEL a split-and-delay unit based on geometrical wavefront beam splitting and multilayer mirrors is built which covers the range of photon energies from 5 keV up to 20 keV. Maximum delays between Δτ=±2.5  ps at hν=20  keV and up to Δτ=±23  ps at hν=5  keV will be possible. Time-dependent wave-optics simulations have been performed by means of Synchrotron Radiation Workshop software for XFEL pulses at hν=5  keV. The XFEL radiation was simulated using results of time-dependent simulations applying the self-amplified spontaneous emission code FAST. Main features of the optical layout, including diffraction on the beam splitter edge and optics imperfections measured with a nanometer optic component measuring machine slope measuring profiler, were taken into account. The impact of these effects on the characterization of the temporal properties of XFEL pulses is analyzed. An approach based on fast Fourier transformation allows for the evaluation of the temporal coherence despite large wavefront distortions caused by the optics imperfections. In this way, the fringes resulting from time-dependent two-beam interference can be filtered and evaluated yielding a coherence time of τ_{c}=0.187  fs (HWHM for real, nonperfect mirrors, while for ideal mirrors a coherence time of τ_{c}=0.191  fs (HWHM is expected.

  12. ``Soft X-ray transient'' outbursts which are not soft

    NARCIS (Netherlands)

    Brocksopp, C.; Bandyopadhyay, R.M.; Fender, R.P.

    2004-01-01

    We have accumulated multiwavelength (X-ray, optical, radio) lightcurves for the eight black hole X-ray binaries which have been observed to enter a supposed `soft X-ray transient' outburst, but remained in the low/hard state throughout the outburst. Comparison of the lightcurve morphologies,

  13. Chest X-Ray

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    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- ...

  14. Chest X-Ray

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    Full Text Available ... to consider the likelihood of benefit to your health. While a chest x-ray use a tiny dose of ionizing radiation, the benefit of an accurate diagnosis far outweighs any risk. For more information about chest x-rays, visit Radiology Info dot ...

  15. NuSTAR Hard X-ray Observations of the Energetic Millisecond Pulsars PSR B1821-24, PSR B1937+21, and PSR J0218+4232

    Science.gov (United States)

    Gotthelf, Eric V.; Bogdanov, Slavko

    2017-08-01

    We present NuSTAR hard X-ray timing and spectroscopy of the three exceptionally energetic rotation-powered millisecond pulsars PSRs B1821-24, B1937+21, and J0218+4232. By correcting for frequency and phase drifts of the NuSTAR on-board clock we are able to recover the intrinsic hard X-ray pulse profiles of all three pulsars with a resolution down to pulsars, respectively. We conduct phase-resolved spectroscopy in the 0.5 - 79 keV range for all three objects, obtaining the best yet measurements of the broad-band spectral shape and high-energy pulsed emission to date. We find extensions of the same power-law continua seen at lower energies, with no conclusive evidence for a spectral turnover or break. Extrapolation of the X-ray power-law spectrum to higher energies reveals that a turnover in the 100 keV to 100 MeV range is required to accommodate the high energy gamma-ray emission observed with Fermi LAT, similar to the broad-band spectral energy distribution observed for the Crab pulsar.

  16. NuSTAR study of hard X-ray morphology and spectroscopy of PWN G21.5–0.9

    Energy Technology Data Exchange (ETDEWEB)

    Nynka, Melania; Hailey, Charles J.; Gotthelf, Eric V.; Mori, Kaya; Perez, Kerstin [Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); Reynolds, Stephen P. [Physics Department, NC State University, Raleigh, NC 27695 (United States); An, Hongjun [Department of Physics, McGill University, Rutherford Physics Building, 3600 University Street, Montreal, Quebec H3A 2T8 (Canada); Baganoff, Frederick K. [Center for Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139-4307 (United States); Boggs, Steven E.; Krivonos, Roman; Zoglauer, Andreas [Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States); Christensen, Finn E. [DTU Space, National Space Institute, Technical University of Denmark, Elektrovej 327, DK-2800 Lyngby (Denmark); Craig, William W. [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Grefenstette, Brian W.; Harrison, Fiona A.; Madsen, Kristin K. [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Stern, Daniel [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Wik, Daniel R.; Zhang, William W. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

    2014-07-01

    We present NuSTAR high-energy X-ray observations of the pulsar wind nebula (PWN)/supernova remnant G21.5–0.9. We detect integrated emission from the nebula up to ∼40 keV, and resolve individual spatial features over a broad X-ray band for the first time. The morphology seen by NuSTAR agrees well with that seen by XMM-Newton and Chandra below 10 keV. At high energies, NuSTAR clearly detects non-thermal emission up to ∼20 keV that extends along the eastern and northern rim of the supernova shell. The broadband images clearly demonstrate that X-ray emission from the North Spur and Eastern Limb results predominantly from non-thermal processes. We detect a break in the spatially integrated X-ray spectrum at ∼9 keV that cannot be reproduced by current spectral energy distribution models, implying either a more complex electron injection spectrum or an additional process such as diffusion compared to what has been considered in previous work. We use spatially resolved maps to derive an energy-dependent cooling length scale, L(E)∝E{sup m} with m = –0.21 ± 0.01. We find this to be inconsistent with the model for the morphological evolution with energy described by Kennel and Coroniti. This value, along with the observed steepening in power-law index between radio and X-ray, can be quantitatively explained as an energy-loss spectral break in the simple scaling model of Reynolds, assuming particle advection dominates over diffusion. This interpretation requires a substantial departure from spherical magnetohydrodynamic, magnetic-flux-conserving outflow, most plausibly in the form of turbulent magnetic-field amplification.

  17. Experimental X-Ray Ghost Imaging.

    Science.gov (United States)

    Pelliccia, Daniele; Rack, Alexander; Scheel, Mario; Cantelli, Valentina; Paganin, David M

    2016-09-09

    We report an experimental proof of principle for ghost imaging in the hard-x-ray energy range. We use a synchrotron x-ray beam that is split using a thin crystal in Laue diffraction geometry. With an ultrafast imaging camera, we are able to image x rays generated by isolated electron bunches. At this time scale, the shot noise of the synchrotron emission process is measurable as speckles, leading to speckle correlation between the two beams. The integrated transmitted intensity from a sample located in the first beam is correlated with the spatially resolved intensity measured in the second, empty, beam to retrieve the shadow of the sample. The demonstration of ghost imaging with hard x rays may open the way to protocols to reduce radiation damage in medical imaging and in nondestructive structural characterization using free electron lasers.

  18. X-Ray Point-source Populations Constituting the Galactic Ridge X-Ray Emission

    Science.gov (United States)

    Morihana, Kumiko; Tsujimoto, Masahiro; Yoshida, Tessei; Ebisawa, Ken

    2013-03-01

    Apparently diffuse X-ray emission has been known to exist along the central quarter of the Galactic Plane since the beginning of X-ray astronomy; this is referred to as the Galactic Ridge X-ray emission (GRXE). Recent deep X-ray observations have shown that numerous X-ray point sources account for a large fraction of the GRXE in the hard band (2-8 keV). However, the nature of these sources is poorly understood. Using the deepest X-ray observations made in the Chandra bulge field, we present the result of a coherent photometric and spectroscopic analysis of individual X-ray point sources for the purpose of constraining their nature and deriving their fractional contributions to the hard-band continuum and Fe K line emission of the GRXE. Based on the X-ray color-color diagram, we divided the point sources into three groups: A (hard), B (soft and broad spectrum), and C (soft and peaked spectrum). The group A sources are further decomposed spectrally into thermal and non-thermal sources with different fractions in different flux ranges. From their X-ray properties, we speculate that the group A non-thermal sources are mostly active galactic nuclei and the thermal sources are mostly white dwarf (WD) binaries such as magnetic and non-magnetic cataclysmic variables (CVs), pre-CVs, and symbiotic stars, whereas the group B and C sources are X-ray active stars in flares and quiescence, respectively. In the log N-log S curve of the 2-8 keV band, the group A non-thermal sources are dominant above ≈10-14 erg cm-2 s-1, which is gradually taken over by Galactic sources in the fainter flux ranges. The Fe Kα emission is mostly from the group A thermal (WD binaries) and the group B (X-ray active stars) sources.

  19. The Seyfert 2 galaxy NGC 2110: hard X-ray emission observed by NuSTAR and variability of the iron Kα line

    DEFF Research Database (Denmark)

    Marinucci, A.; Matt, G.; Bianchi, S.

    2015-01-01

    We present NuSTAR observations of the bright Seyfert 2 galaxy NGC 2110 obtained in 2012, when the source was at the highest flux level ever observed, and in 2013, when the source was at a more typical flux level. We include archival observations from other X-ray satellites, namely XMM-Newton, Suz......We present NuSTAR observations of the bright Seyfert 2 galaxy NGC 2110 obtained in 2012, when the source was at the highest flux level ever observed, and in 2013, when the source was at a more typical flux level. We include archival observations from other X-ray satellites, namely XMM...... is found and, by using temporal information collected over more than a decade, we investigate variations of the iron Kα line on time-scales of years. The Fe K alpha line is likely the sum of two components: one constant (originating from distant Compton-thick material) and the other one variable...

  20. X-ray imaging

    Energy Technology Data Exchange (ETDEWEB)

    Fenster, A. [Univ. of Western Ontario, J.P. Robarts Institute, London, Ontario (Canada); Yaffe, M.J. [Univ. of Toronto, Depts. of Medical Biophysics and Medical Imaging, North York, Ontario (Canada)

    1995-09-01

    In this article, we briefly review the principles of x-ray imaging, consider some of its applications in medicine and describe some of the developments in this area which have taken place in Canada. X rays were first used for diagnosis and therapy in medicine almost immediately after the report of their discovery by Roentgen in 1895. X-ray imaging has remained the primary tool for the investigation of structures within the body up to the present time (Johns and Cunningham 1983). Medical x rays are produced in a vacuum tube by the electron bombardment of a metallic target. Electrons emitted from a heated cathode are accelerated through an electric field to energies of 20-150 keV (wavelength 6.2-0.83 nm) and strike a target anode. X rays appear in a spectrum of bremsstrahlung radiation with energies ranging from 0 to a value that is numerically equal to the peak voltage applied between the cathode and anode of the x-ray tube (Figure 1). In addition, where the energy of the impinging electrons exceeds the binding energy of inner atomic orbitals of the target material, electrons may be ejected from those shells. Filling of these shells by more loosely-bound electrons gives rise to x rays whose energies are equal to the difference of the binding energies of the donor and acceptor shells. The energies of these characteristic x rays are unique to the target material. Less than 1% of the energy of the incident electrons is converted to that of x rays, while the remainder is dissipated as heat in the target. For this reason, a tremendous amount of engineering has gone into the design of x-ray tubes that can yield a large fluence rate of quanta from a small effective source size, while withstanding the enormous applied heat loading (e.g. 10 kJ per exposure). Tungsten is by far the most common material used for targets in tubes for diagnostic radiology, because of its high melting point and its high atomic number; the efficiency of x-ray production is proportional to Z of the

  1. 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

  2. Bone X-Ray (Radiography)

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    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 ...

  4. Abdomen X-Ray (Radiography)

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    ... 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 ...

  5. Chest X-Ray

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    Full Text Available ... Imaging Costs Video: Abdominal Ultrasound Video: Pelvic Ultrasound Radiology and You Sponsored by Image/Video Gallery Your Radiologist Explains Chest X-ray Transcript Welcome to Radiology Info dot org! Hello, I’m Dr. Geoffrey ...

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    Full Text Available ... Index A-Z Spotlight March is National Colorectal Cancer Awareness Month Recently posted: Carotid Intima-Media Thickness ... of lung conditions such as pneumonia, emphysema and cancer. A chest x-ray requires no special preparation. ...

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    Full Text Available ... Site Index A-Z Spotlight February is American Heart Month Recently posted: Carotid Intima-Media Thickness Test ... x-ray is used to evaluate the lungs, heart and chest wall and may be used to ...

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    Full Text Available ... chest x-ray is used to evaluate the lungs, heart and chest wall and may be used ... diagnose and monitor treatment for a variety of lung conditions such as pneumonia, emphysema and cancer. A ...

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    Full Text Available ... breath, persistent cough, fever, chest pain or injury. It may also be useful to help diagnose and ... have some concerns about chest x-rays. However, it’s important to consider the likelihood of benefit to ...

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    Full Text Available ... accurate diagnosis far outweighs any risk. For more information about chest x-rays, visit Radiology Info dot ... Inc. (RSNA). To help ensure current and accurate information, we do not permit copying but encourage linking ...

  11. Sinus x-ray

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    ... an infection and inflammation of the sinuses called sinusitis . A sinus x-ray is ordered when you have any of the following: Symptoms of sinusitis Other sinus disorders, such as a deviated septum ( ...

  12. Chest X-Ray

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    Full Text Available ... Index A-Z Spotlight November is National Lung Cancer Awareness Month Recently posted: Carotid Intima-Media Thickness ... of lung conditions such as pneumonia, emphysema and cancer. A chest x-ray requires no special preparation. ...

  13. Chest X-Ray

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    Full Text Available ... exams and use a very small dose of ionizing radiation to produce pictures of the inside of the ... chest x-ray use a tiny dose of ionizing radiation, the benefit of an accurate diagnosis far outweighs ...

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    Full Text Available ... and You Take our survey Sponsored by Image/Video Gallery Your Radiologist Explains Chest X-ray Transcript ... Carotid Intima-Media Thickness Test Medical Imaging Costs Video: Abdominal Ultrasound Video: Pelvic Ultrasound Radiology and You ...

  15. X-ray

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    ... X-ray References Geleijns J, Tack D. Medical physics: radiation risks. In: Adam A, Dixon AK, Gillard ... Updated by: C. Benjamin Ma, MD, Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic ...

  16. Chest X-Ray

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    Full Text Available ... and use a very small dose of ionizing radiation to produce pictures of the inside of the ... x-ray use a tiny dose of ionizing radiation, the benefit of an accurate diagnosis far outweighs ...

  17. Chest X-Ray

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    Full Text Available ... Your Radiologist Explains Chest X-ray Transcript Welcome to Radiology Info dot org! Hello, I’m Dr. ... University in Durham, North Carolina. I’d like to talk with you about chest radiography also known ...

  18. Chest X-Ray

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    Full Text Available ... Index A-Z Spotlight October is National Breast Cancer Awareness Month Recently posted: Carotid Intima-Media Thickness ... of lung conditions such as pneumonia, emphysema and cancer. A chest x-ray requires no special preparation. ...

  19. Bone X-Ray (Radiography)

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  20. Bone X-Ray (Radiography)

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    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 ...

  1. Bone X-Ray (Radiography)

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    Full Text Available ... position possible that still ensures x-ray image quality. top of page Who interprets the results and ... standards used by radiology professionals. Modern x-ray systems have very controlled x-ray beams and dose ...

  2. 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? ... standards used by radiology professionals. Modern x-ray systems have very controlled x-ray beams and dose ...

  3. Bone X-Ray (Radiography)

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    Full Text Available ... ray examination. X-rays usually have no side effects in the typical diagnostic range for this exam. ... Media Arthritis X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety Images related to X-ray (Radiography) - ...

  4. 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 ...

  5. Bone X-Ray (Radiography)

    Medline Plus

    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 ...

  6. Demonstration of X-ray talbot interferometry

    CERN Document Server

    Momose, A; Kawamoto, S; Hamaishi, Y; Takai, K; Suzuki, Y

    2003-01-01

    First Talbot interferometry in the hard X-ray region was demonstrated using a pair of transmission gratings made by forming gold stripes on glass plates. By aligning the gratings on the optical axis of X-rays with a separation that caused the Talbot effect by the first grating, moire fringes were produced inclining one grating slightly against the other around the optical axis. A phase object placed in front of the first grating was detected by moire-fringe bending. Using the technique of phase-shifting interferometry, the differential phase corresponding to the phase object could also be measured. This result suggests that X-ray Talbot interferometry is a novel and simple method for phase-sensitive X-ray radiography. (author)

  7. Suzaku  Observations of Heavily Obscured (Compton-thick) Active Galactic Nuclei Selected by the Swift/BAT Hard X-Ray Survey

    Science.gov (United States)

    Tanimoto, Atsushi; Ueda, Yoshihiro; Kawamuro, Taiki; Ricci, Claudio; Awaki, Hisamitsu; Terashima, Yuichi

    2018-02-01

    We present a uniform broadband X-ray (0.5–100.0 keV) spectral analysis of 12 Swift/Burst Alert Telescope selected Compton-thick ({log}{N}{{H}}/{{cm}}-2≥slant 24) active galactic nuclei (CTAGNs) observed with Suzaku. The Suzaku data of three objects are published here for the first time. We fit the Suzaku and Swift spectra with models utilizing an analytic reflection code and those utilizing the Monte-Carlo-based model from an AGN torus by Ikeda et al. The main results are as follows: (1) The estimated intrinsic luminosity of a CTAGN strongly depends on the model; applying Compton scattering to the transmitted component in an analytic model may largely overestimate the intrinsic luminosity at large column densities. (2) Unabsorbed reflection components are commonly observed, suggesting that the tori are clumpy. (3) Most of CTAGNs show small scattering fractions (X-ray-selected CTAGNs are different from less obscured objects.

  8. The Cryogenic AntiCoincidence detector for ATHENA X-IFU: a scientific assessment of the observational capabilities in the hard X-ray band

    Science.gov (United States)

    D'Andrea, M.; Lotti, S.; Macculi, C.; Piro, L.; Argan, A.; Gatti, F.

    2017-12-01

    ATHENA is a large X-ray observatory, planned to be launched by ESA in 2028 towards an L2 orbit. One of the two instruments of the payload is the X-IFU: a cryogenic spectrometer based on a large array of TES microcalorimeters, able to perform integral field spectrography in the 0.2-12 keV band (2.5 eV FWHM at 6 keV). The X-IFU sensitivity is highly degraded by the particle background expected in the L2 orbit, which is induced by primary protons of both galactic and solar origin, and mostly by secondary electrons. To reduce the particle background level and enable the mission science goals, the instrument incorporates a Cryogenic AntiCoincidence detector (CryoAC). It is a 4 pixel TES based detector, placed 10 keV). The aim of the study has been to understand if the present detector design can be improved in order to enlarge the X-IFU scientific capability on an energy band wider than the TES array. This is beyond the CryoAC baseline, being this instrument aimed to operate as anticoincidence particle detector and not conceived to perform X-ray observations.

  9. 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

  10. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... the limitations of Bone X-ray (Radiography)? What is Bone X-ray (Radiography)? An x-ray (radiograph) ... top of page What are some common uses of the procedure? A bone x-ray is used ...

  11. Lumbosacral spine x-ray

    Science.gov (United States)

    X-ray - lumbosacral spine; X-ray - lower spine ... be placed over the lower part of your spine. You will be asked to hold your breath ... x-ray. The most common reason for lumbosacral spine x-ray is to look for the cause ...

  12. Reconstruction of surface morphology from coherent scattering of ''white'' synchrotron radiation in hard X-ray regime

    Energy Technology Data Exchange (ETDEWEB)

    Sant, Tushar

    2009-07-01

    Energy Dispersive Reflectometry (EDR) beamline at BESSY II provides ''white'' X-rays in the useful energy range of 5

  13. Technology development for soft X-ray spectroscopy

    Science.gov (United States)

    Törmä, P. T.; Sipilä, H. J.; Koskinen, T.; Mattila, M.

    2016-05-01

    X-ray spectroscopy instruments lose part of their performance due to the lack of suitable components for soft X-ray region below 1 keV. Therefore, in the analysis of low atomic number elements including lithium, beryllium, boron and carbon instrument sensitivity is often limited. In this work we describe how the performance of the spectroscopy of soft X-rays is significantly improved when all devices integrated in the spectroscopic instrument are suitable for both soft and hard X-rays. This concept is based on utilizing ultra-thin SiN X-ray windows with proven performance not only as a detector window but also as an X-ray source window. By including a soft-X-ray-sensitive silicon drift detector with efficient surface charge collection in this concept the sensitivity and performance of the instrument is significantly increased.

  14. Chest X-Ray

    Medline Plus

    Full Text Available ... of ionizing radiation, the benefit of an accurate diagnosis far outweighs any risk. For more information about chest x-rays, visit Radiology Info dot org. Thank you for your time! Spotlight November is National Lung Cancer Awareness Month Recently posted: Carotid Intima-Media Thickness ...

  15. Chest X-Ray

    Medline Plus

    Full Text Available ... Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions ... Explains Chest X-ray Transcript Welcome to Radiology Info dot org! Hello, I’m Dr. Geoffrey Rubin, ...

  16. Pelvis x-ray

    Science.gov (United States)

    The x-ray is used to look for: Fractures Tumors Degenerative conditions of bones in the hips, pelvis, and upper legs ... Abnormal results may suggest: Pelvic fractures Arthritis of the hip joint ... spondylitis (abnormal stiffness of the spine and joint) ...

  17. Chest X-Ray

    Medline Plus

    Full Text Available ... Radiology (IDoR) Radiology and You Sponsored by Image/Video Gallery Your Radiologist Explains Chest X-ray Transcript ... Carotid Intima-Media Thickness Test Medical Imaging Costs Video: Abdominal Ultrasound Video: Pelvic Ultrasound November 8 is ...

  18. 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.

  19. Dark field X-ray microscopy for studies of recrystallization

    DEFF Research Database (Denmark)

    Ahl, Sonja Rosenlund; Simons, Hugh; Jakobsen, Anders Clemen

    2015-01-01

    We present the recently developed technique of Dark Field X-Ray Microscopy that utilizes the diffraction of hard X-rays from individual grains or subgrains at the (sub)micrometre- scale embedded within mm-sized samples. By magnifying the diffracted signal, 3D mapping of orientations and strains...... external influences. The capabilities of Dark Field X- Ray Microscopy are illustrated by examples from an ongoing study of recrystallization of 50% cold-rolled Al1050 specimens....

  20. High-resolution fluorescence mapping of impurities in historical zinc oxide pigments: hard X-ray nanoprobe applications to the paints of Pablo Picasso

    Energy Technology Data Exchange (ETDEWEB)

    Casadio, Francesca [The Art Institute of Chicago, Chicago, IL (United States); Rose, Volker [Argonne National Laboratory, Advanced Photon Source and Center for Nanoscale Materials, Argonne, IL (United States)

    2013-04-15

    Here for the first time we describe the use of high resolution nanoprobe X-ray fluorescence (XRF) mapping for the analysis of artists' paints, hierarchically complex materials typically composed of binder, pigments, fillers, and other additives. The work undertaken at the nanoprobe sought to obtain highly spatially resolved, highly sensitive mapping of metal impurities (Pb, Cd, Fe, and other metals) in submicron particles of zinc oxide pigments used in early 20th century artists' tube paints and enamel paints, with particular emphasis on Ripolin, a popular brand of French house paint used extensively by Pablo Picasso and some of his contemporaries. Analysis revealed that the Zn oxide particles only contain a little Fe, proving that the highest quality Zn oxide pigment, free of Pb and Cd, was used for Ripolin house paints as well as artists' paints. Nanoprobe XRF mapping also demonstrated that artists' tube paints generally have more abundant fillers and additional whites (based on Pb, Ti, Ca) than Ripolin paints, which contain mostly pure zinc oxide. The chemical characterization of paints at the nanoscale opens the path to a better understanding of their fabrication and chemical reactivity. (orig.)