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Sample records for hard x-rays fabricated

  1. Fabrication of 200 nanometer period centimeter area hard x-ray absorption gratings by multilayer deposition

    PubMed Central

    Lynch, S K; Liu, C; Morgan, N Y; Xiao, X; Gomella, A A; Mazilu, D; Bennett, E E; Assoufid, L; de Carlo, F; Wen, H

    2012-01-01

    We describe the design and fabrication trials of x-ray absorption gratings of 200 nm period and up to 100:1 depth-to-period ratios for full-field hard x-ray imaging applications. Hard x-ray phase-contrast imaging relies on gratings of ultra-small periods and sufficient depth to achieve high sensitivity. Current grating designs utilize lithographic processes to produce periodic vertical structures, where grating periods below 2.0 μm are difficult due to the extreme aspect ratios of the structures. In our design, multiple bilayers of x-ray transparent and opaque materials are deposited on a staircase substrate, and mostly on the floor surfaces of the steps only. When illuminated by an x-ray beam horizontally, the multilayer stack on each step functions as a micro-grating whose grating period is the thickness of a bilayer. The array of micro-gratings over the length of the staircase works as a single grating over a large area when continuity conditions are met. Since the layers can be nanometers thick and many microns wide, this design allows sub-micron grating periods and sufficient grating depth to modulate hard x-rays. We present the details of the fabrication process and diffraction profiles and contact radiography images showing successful intensity modulation of a 25 keV x-ray beam. PMID:23066175

  2. Fabrication of 200 nanometer period centimeter area hard x-ray absorption gratings by multilayer deposition.

    PubMed

    Lynch, S K; Liu, C; Morgan, N Y; Xiao, X; Gomella, A A; Mazilu, D; Bennett, E E; Assoufid, L; de Carlo, F; Wen, H

    2012-10-01

    We describe the design and fabrication trials of x-ray absorption gratings of 200 nm period and up to 100:1 depth-to-period ratios for full-field hard x-ray imaging applications. Hard x-ray phase-contrast imaging relies on gratings of ultra-small periods and sufficient depth to achieve high sensitivity. Current grating designs utilize lithographic processes to produce periodic vertical structures, where grating periods below 2.0 μm are difficult due to the extreme aspect ratios of the structures. In our design, multiple bilayers of x-ray transparent and opaque materials are deposited on a staircase substrate, and mostly on the floor surfaces of the steps only. When illuminated by an x-ray beam horizontally, the multilayer stack on each step functions as a micro-grating whose grating period is the thickness of a bilayer. The array of micro-gratings over the length of the staircase works as a single grating over a large area when continuity conditions are met. Since the layers can be nanometers thick and many microns wide, this design allows sub-micron grating periods and sufficient grating depth to modulate hard x-rays. We present the details of the fabrication process and diffraction profiles and contact radiography images showing successful intensity modulation of a 25 keV x-ray beam. PMID:23066175

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

    SciTech Connect

    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.

  4. MZP design and fabrication for efficient hard x-ray nano-focusing and imaging

    NASA Astrophysics Data System (ADS)

    Eberl, Christian; Osterhoff, Markus; Döring, Florian; Krebs, Hans-Ulrich

    2015-08-01

    Efficient focusing optics are a key ingredient for high-resolution (few nanometer) hard x-ray imaging. In recent years, a combined optical scheme using prefocusing to match the coherent fraction of the synchrotron's x-ray beam to a high-resolution multilayer zone plate (MZP) has been presented. This scheme allows sub-5 nm focusing of hard x-rays in two dimensions. Nevertheless, the first lenses prepared by pulsed laser deposition of alternating WW and Si layers were limited by a low deposition rate of W and the formation of lots of Si-droplets during film growth. Thus, the material combination has been changed to Ta2O5 and ZrO2, allowing a much faster and more accurate layer growth. Here we present latest developments achieved in both design and fabrication of high-resolution MMZPs: A MZP with a lens diameters of about 15 micrometers, sharp layer interfaces, 5 nm outermost zone widths and a focal length of 0.5 mm. Too increase the focusing efficiency even more, a tilted geometry using a pulled glass fibre was successfully implemented.

  5. Optics fabrication and metrology for nanofocusing of hard x-rays

    SciTech Connect

    Macrander, A. T.; Liu, C.; Conley, R.; Assoufid, L.; Khounsary, A.; Qian, J.; Kewish, C. M.; X-Ray Science Division

    2006-01-01

    Progress in the fabrication and metrology of both Multilayer Laue Lenses (MLLs) and Kirkpatrick-Baez (K-B) mirrors at the Advanced Photon Source (APS) is on-going as part of the world-wide race to achieve ever smaller focusing. Successful MLLs require multilayer depositions consisting of many layers. Focusing to 30 nm for 19.5 keV has been demonstrated at APS beamlines with a WSi2/Si MLL having 728 layers made at the APS. These same techniques were used to achieve a partial linear zone plate structure having a 5-nm outer most zone width and consisting of 1588 total layers as discussed below. Achromatic focusing to 80 nm of x-rays in the range {approx}7 to 22 keV by an elliptically figured K-B mirror has been demonstrated at the APS with a mirror coated at the APS. The mirror was made by profile coating a substrate with Au to achieve the elliptical surface shape. The elliptical mirror was made starting from a flat substrate. To make further progress, non-x-ray-based metrology data for real mirrors will need to be incorporated into simulations. This is being done using Fourier Optics methods as detailed below. Multilayer Laue Lens with 5-nm outermost zone - A scanning electron micrograph of a cross section of a 5-nm MLL structure is shown in Fig.1, below. The bilayer structure was WSi{sub 2}/Si and a total of 1588 layers were sputter deposited at the APS. The micrograph was read to obtain the data plotted in Fig. 2. Here the d-spacing as a function of position in the lens is shown, where the d-spacing is twice the individual layer spacing A linear behavior in 1/d vs. position is needed to satisfy the zone plate law. (Owing to limited SEM resolution, the thinnest layers were subject to greater uncertainty.) This lens was used to obtain a linear focus of 19.3 nm at 19.5 keV at beamline 12-BM at the APS. Kirkpatrick-Baez mirrors and Fourier Optics Simulations - Elliptically shaped mirrors have been made by profile coating at the APS. A program to simulate the

  6. Hard X-Ray Emission of X-Ray Bursters

    NASA Technical Reports Server (NTRS)

    Kaaret, P.

    1999-01-01

    The primary goal of this proposal was to perform an accurate measurement of the broadband x-ray spectrum of a neutron-star low-mass x-ray binary found in a hard x-ray state. This goal was accomplished using data obtained under another proposal, which has provided exciting new information on the hard x-ray emission of neutron-star low-mass x-ray binaries. In "BeppoSAX Observations of the Atoll X-Ray Binary 4U0614+091", we present our analysis of the spectrum of 4U0614+091 over the energy band from 0.3-150 keV. Our data confirm the presence of a hard x-ray tail that can be modeled as thermal Comptonization of low-energy photons on electrons having a very high temperature, greater than 220 keV, or as a non-thermal powerlaw. Such a very hard x-ray spectrum has not been previously seen from neutron-star low-mass x-ray binaries. We also detected a spectral feature that can be interpreted as reprocessing, via Compton reflection, of the direct emission by an optically-thick disk and found a correlation between the photon index of the power-law tail and the fraction of radiation reflected which is similar to the correlation found for black hole candidate x-ray binaries and Seyfert galaxies. A secondary goal was to measure the timing properties of the x-ray emission from neutronstar low-mass x-ray binaries in their low/hard states.

  7. Hard X-ray emission from X-ray bursters.

    NASA Astrophysics Data System (ADS)

    Tavani, M.; Liang, E.

    1996-11-01

    Hard X-ray emission from compact objects has been considered a spectral signature of black hole candidates. However, SIGMA and BATSE recently detected transient emission in the energy range 30-200keV from several X-ray bursters (XRBs) believed to contain weakly magnetized neutron stars. At least seven XRBs (including Aquila X-1 and 4U 1608-52) are currently known to produce erratic hard X-ray outbursts with typical durations of several weeks. These results lead us to reconsider theoretical models of high-energy emission from compact objects, and in particular thermal Comptonization models vs. non-thermal models of particle energization and X-ray emission from weakly magnetized neutron stars. We summarize here recent results for magnetic field reconnection models of non-thermal particle acceleration and high-energy emission of accretion disks. For intermediate soft X-ray luminosities below the Eddington limit, non-thermal hard X-ray emission is predicted to have a (broken) power-law spectrum with intensity anticorrelated with the soft X-ray luminosity. Recent GINGA/BATSE data for the XRB 4U 1608-52 are in agreement with the mechanism of emission proposed here: transient hard X-ray emission consistent with a broken power-law spectrum was detected for a sub-Eddington soft X-ray luminosity.

  8. Hard X-ray astrophysics

    NASA Technical Reports Server (NTRS)

    Rothschild, R. E.

    1981-01-01

    Past hard X-ray and lower energy satellite instruments are reviewed and it is shown that observation above 20 keV and up to hundreds of keV can provide much valuable information on the astrophysics of cosmic sources. To calculate possible sensitivities of future arrays, the efficiencies of a one-atmosphere inch gas counter (the HEAO-1 A-2 xenon filled HED3) and a 3 mm phoswich scintillator (the HEAO-1 A-4 Na1 LED1) were compared. Above 15 keV, the scintillator was more efficient. In a similar comparison, the sensitivity of germanium detectors did not differ much from that of the scintillators, except at high energies where the sensitivity would remain flat and not rise with loss of efficiency. Questions to be addressed concerning the physics of active galaxies and the diffuse radiation background, black holes, radio pulsars, X-ray pulsars, and galactic clusters are examined.

  9. Hard X-ray Fourier Transform Holography Using a Reference Scatterer Fabricated by Electron-Beam-Assisted Chemical-Vapor Deposition

    SciTech Connect

    Suzuki, M.; Isogami, S.; Tsunoda, M.; Takahashi, S.; Ishio, S.

    2011-09-09

    We present a fabrication method for a reference source that is efficient when used for lensless Fourier transform holography. This method produces a reference source that yields high spatial resolution and enhanced signal-to-noise ratio in a Fourier-transformed real-space image, and is particularly useful for Fourier transform holography experiments in the hard x-ray region.

  10. Hard X-ray imaging from Explorer

    NASA Technical Reports Server (NTRS)

    Grindlay, J. E.; Murray, S. S.

    1981-01-01

    Coded aperture X-ray detectors were applied to obtain large increases in sensitivity as well as angular resolution. A hard X-ray coded aperture detector concept is described which enables very high sensitivity studies persistent hard X-ray sources and gamma ray bursts. Coded aperture imaging is employed so that approx. 2 min source locations can be derived within a 3 deg field of view. Gamma bursts were located initially to within approx. 2 deg and X-ray/hard X-ray spectra and timing, as well as precise locations, derived for possible burst afterglow emission. It is suggested that hard X-ray imaging should be conducted from an Explorer mission where long exposure times are possible.

  11. Fabrication, performance, and figure metrology of epoxy-replicated aluminum foils for hard x-ray focusing multilayer-coated segmented conical optics

    NASA Astrophysics Data System (ADS)

    Jimenez-Garate, Mario A.; Craig, William W.; Hailey, Charles J.; Christensen, Finn E.; Hussain, Ahsen M.

    2000-11-01

    We fabricated x-ray mirrors for hard x-ray (>= 10 keV) telescopes using multilayer coatings and an improved epoxy- replicated aluminum foil (ERAF) nonvacuum technology. The ERAF optics have approximately 1 arcmin axial figure half- power diameter (HPD) and passed environmental testing. Reflectivity measurements at 8 keV on ERAFs with and without multilayer coatings show a 4.4 to 4.8 angstroms room mean square microroughness for correlation lengths hard x-ray conical optics. These developments lower cost and improve the optics performance of the HEFT (high-energy focusing telescope) and Constellation-X missions.

  12. The Development of Hard X-ray Microscopy with MIRRORCLE-6X

    NASA Astrophysics Data System (ADS)

    Hirai, T.; Tokunaga, T.; Yamada, H.; Sasaki, M.; Hasegawa, D.; Ogasaka, Y.; Yamashita, H.

    2004-08-01

    A laboratory-scale hard X-ray microscope utilizing the portable synchrotron named MIRRORCLE-6X is developed in our laboratory. MIRRORCLE-6X is a X-ray source suitable for hard X-ray microscopy as a result of the X-ray source size of the order of micron, and highly brilliant hard X-rays. Furthermore, when effective focusing elements of hard X-rays are used for MIRRORCLE-6X, this machine could be used for non destructive inspection with high resolution of biological and engineering. We designed hard X-ray optical elements for MIRRORCLE6X and started fabricating X-ray mirrors.

  13. Enhanced adhesion buffer layer for deep x-ray lithography using hard x-rays.

    SciTech Connect

    De Carlo, F.

    1998-08-28

    The first step in the fabrication of microstructure using deep x-ray lithography (DXRL) is the irradiation of a x-ray sensitive resist like polymethylmethacrylate (PMMA) by hard x-rays. At the Advanced Photon Source, a dedicated beamline allows the proper exposure of very thick (several mm) resists. To fabricate electroformed metal microstructure with heights of several mm, a PMMA sheet is glued onto a metallic plating base. An important requirement is that the PMMA layer must adhere well to the plating base. The adhesion is greatly reduced by the penetration of even a small fraction of hard x-rays through the mask absorber into the substrate. In this work we will show a novel technique to improve the adhesion of PMMA onto high-Z substrates for DXRL. Results of the improved adhesion are shown for different exposure/substrate conditions.

  14. Solar flare hard X-ray observations

    NASA Technical Reports Server (NTRS)

    Dennis, Brian R.

    1988-01-01

    Recent hard X-ray observations of solar flares are reviewed with emphasis on results obtained with instruments on the solar maximum satellite. Flares with three sets of characteristics, designated as Type A, Type B, and Type C, are discussed and hard X-ray temporal, spatial spectral, and polarization measurements are reviewed in this framework. Coincident observations are reviewed at other wavelengths including the UV, microwaves, and soft X-rays, with discussions of their interpretations. In conclusion, a brief outline is presented of the potential of future hard X-ray observations with sub-second time resolution, arcsecond spatial resolution, and keV energy resolution, and polarization measurements at the few percent level up to 100 keV.

  15. Refractive Optics for Hard X-ray Transmission Microscopy

    SciTech Connect

    Simon, M.; Last, A.; Mohr, J.; Nazmov, V.; Reznikova, E.; Ahrens, G.; Voigt, A.

    2011-09-09

    For hard x-ray transmission microscopy at photon energies higher than 15 keV we design refractive condenser and imaging elements to be used with synchrotron light sources as well as with x-ray tube sources. The condenser lenses are optimized for low x-ray attenuation--resulting in apertures greater than 1 mm--and homogeneous intensity distribution on the detector plane, whereas the imaging enables high-resolution (<100 nm) full-field imaging. To obtain high image quality at reasonable exposure times, custom-tailored matched pairs of condenser and imaging lenses are being developed. The imaging lenses (compound refractive lenses, CRLs) are made of SU-8 negative resist by deep x-ray lithography. SU-8 shows high radiation stability. The fabrication technique enables high-quality lens structures regarding surface roughness and arrangement precision with arbitrary 2D geometry. To provide point foci, crossed pairs of lenses are used. Condenser lenses have been made utilizing deep x-ray lithographic patterning of thick SU-8 layers, too, whereas in this case, the aperture is limited due to process restrictions. Thus, in terms of large apertures, condenser lenses made of structured and rolled polyimide film are more attractive. Both condenser types, x-ray mosaic lenses and rolled x-ray prism lenses (RXPLs), are considered to be implemented into a microscope setup. The x-ray optical elements mentioned above are characterized with synchrotron radiation and x-ray laboratory sources, respectively.

  16. Kirkpatrick-Baez mirrors to focus hard X-rays in two dimensions as fabricated, tested and installed at the Advanced Photon Source.

    PubMed

    Kujala, Naresh; Marathe, Shashidhara; Shu, Deming; Shi, Bing; Qian, Jun; Maxey, Evan; Finney, Lydia; Macrander, Albert; Assoufid, Lahsen

    2014-07-01

    The micro-focusing performance for hard X-rays of a fixed-geometry elliptical Kirkpatrick-Baez (K-B) mirrors assembly fabricated, tested and finally implemented at the micro-probe beamline 8-BM of the Advanced Photon Source is reported. Testing of the K-B mirror system was performed at the optics and detector test beamline 1-BM. K-B mirrors of length 80 mm and 60 mm were fabricated by profile coating with Pt metal to produce focal lengths of 250 mm and 155 mm for 3 mrad incident angle. For the critical angle of Pt, a broad bandwidth of energies up to 20 keV applies. The classical K-B sequential mirror geometry was used, and mirrors were mounted on micro-translation stages. The beam intensity profiles were measured by differentiating the curves of intensity data measured using a wire-scanning method. A beam size of 1.3 µm (V) and 1.2 µm (H) was measured with monochromatic X-rays of 18 keV at 1-BM. After installation at 8-BM the measured focus met the design requirements. In this paper the fabrication and metrology of the K-B mirrors are reported, as well as the focusing performances of the full mirrors-plus-mount set-up at both beamlines. PMID:24971959

  17. Replicated Nickel Optics for the Hard-X-Ray Region

    NASA Technical Reports Server (NTRS)

    Ramsey, Brian

    2005-01-01

    Replicated nickel optics has been used extensively in x-ray astronomy, most notable for the XMM/Newton mission. Thc combination of relative ease of fabrication and the inherent stability of full shell optics, make them FIJI attractive approach for medium-resolution, high-throughput applications. MSFC has been developing these optics for use in the hard-x-ray region. Efforts at improving the resolution of these, particularly the very-thin shells required to meet thc weight budget of future missions, will be described together with the prospects for significant improvements down to the 5-arcsec level.

  18. Multilayer Monochromator For Hard X Rays And Gamma Rays

    NASA Technical Reports Server (NTRS)

    Hoover, Richard B.

    1992-01-01

    Compact monochromator for hard x rays and gamma rays provides high spectral resolution with high throughput. Resembles instruments in "Compact X-Ray and Extreme-Ultraviolet Monochromator" (MFS-28499), "Scanning X-Ray or Extreme-Ultraviolet Monochromator" (MFS-28492), "Ultra-High-Spectral-Resolution X-Ray/EUV Monochromator" (MFS-28500), and "Four-Mirror X-Ray and Extreme-Ultraviolet Monochromator" (MFS-28498). Operates on principle of multilayer Bragg reflector. Used in nuclear, astronomical, and biomedical research, x-ray crystallography, research on processing materials, research in x-ray lasers, and x-ray lithography.

  19. Soft X-Ray Spectra of AGN Discovered Via Their Hard X-Ray

    NASA Technical Reports Server (NTRS)

    Schwartz, Daniel

    1998-01-01

    This final report is a study of the Active Galactic Nuclei (AGN). Investigation of the soft x-ray spectra of AGN were performed by using their hard x-ray emission. ROSAT observations of AGN was also performed, which allowed for the study of these x-ray spectra and the structures of 7 clusters of galaxies.

  20. Hard x ray/microwave spectroscopy of solar flares

    NASA Technical Reports Server (NTRS)

    Gary, Dale E.

    1992-01-01

    The joint study of hard x ray and microwave observations of solar flares is extremely important because the two complementary ways of viewing the accelerated electrons yield information that cannot be obtained using hard x rays or microwaves alone. The microwaves can provide spatial information lacking in the hard x rays, and the x ray data can give information on the energy distribution of electrons that remove ambiguities in the radio data. A prerequisite for combining the two data-sets, however, is to first understand which range of microwave frequencies correlate best with the hard x rays. This SMM Guest Investigator grant enabled us to combine multi-frequency OVRO data with calibrated hard x ray data to shed light on the relationship between the two emissions. In particular, the questions of which microwave frequencies correspond to which hard x ray energies, and what is the corresponding energy of the electrons that produce both types of emission are investigated.

  1. Hard X-ray Nano Patterning using a Sectioned Multilayer

    SciTech Connect

    S Lee; I Cho; J Kim; H Yan; R Conley; C Liu; A Macrander; J Maser; G Stephenson; et al.

    2011-12-31

    We report a hard x-ray patterning capable of drawing lines with a width below 100 nm using x-rays at 0.165 nm. A specially prepared mask based on multilayer growth technology was used as an x-ray mask effectively. The x-ray Talbot effect in near field was investigated and utilized in the patterning. Since multilayers with a few nanometer layer spacing are readily available, the proposed hard x-ray nano patterning, free of the limit imposed by the Rayleigh criterion in optical range, can potentially be an ultimate optical lithography technique.

  2. X-ray magnetic circular dichroism imaging with hard X-rays.

    PubMed

    Sato, K; Ueji, Y; Okitsu, K; Matsushita, T; Amemiya, Y

    2001-05-01

    X-ray polarization-contrast images resulting from X-ray magnetic circular dichroism (XMCD) in the hard X-ray region have been successfully recorded for the first time. The apparatus used consisted of an X-ray polarizer, double X-ray phase retarders, and a high-spatial-resolution X-ray charge-coupled-device detector. The sample used was a hexagonal-close-packed cobalt polycrystal foil having a thickness of about 4 microns. The X-ray polarization-contrast image resulting from XMCD was observed at a photon energy of 10 eV above the cobalt K-absorption edge (7709 eV). The observed contrast in the image was reversed by inversion of the magnetic field. Furthermore, the contrast was reversed again at a photon energy of 32 eV above the cobalt K-absorption edge. PMID:11486407

  3. Diamond refractive lens for hard x-ray focusing

    NASA Astrophysics Data System (ADS)

    Snigirev, Anatoly A.; Yunkin, Vecheslav; Snigireva, Irina; Di Michiel, Marco; Drakopoulos, Michael; Kouznetsov, Sergey; Shabel'nikov, Leonid; Grigoriev, Michail; Ralchenko, Victor; Sychov, I.; Hoffmann, Martin; Voges, Edgar I.

    2002-11-01

    We report the manufacture and experimental tests of first diamond refractive lenses for hard X-ray focusing. A transfer molding technique based on diamond growth on a pre-patterned silicon mould was employed to fabricate diamond refractive lenses. Diamond films were produced by microwave plasma enhanced chemical vapor deposition. The lenses were designed for 50 cm focal length at energy 9 keV. Experimental tests were performed at the ESRF ID15 (wiggler) and ID22 (undulator) beamlines using monochromatic, "pink" and white X-ray radiation in the energy range from 6 to 40 keV. Focusing in the order of 1-2 microns was achieved. To evaluate the lens microstructure properties phase contrast imaging and diffraction techniques (SAXS and WAXS) were applied.

  4. The smallest hard X-ray flare?

    NASA Astrophysics Data System (ADS)

    Glesener, Lindsay; Krucker, Sam; Hannah, Iain; Smith, David M.; Grefenstette, Brian; Marsh, Andrew; Hudson, Hugh S.; White, Stephen M.; Chen, Bin

    2016-05-01

    We report a NuSTAR observation of a small solar flare on 2015 September 1, estimated to be on the order of a GOES class A.05 flare in brightness. This flare is fainter than any hard X-ray (HXR) flares in the existing literature, and with a peak rate of only ∼5 counts s‑1 detector‑1 observed by RHESSI, is effectively the smallest that can just barely be detected by the current standard (indirectly imaging) solar HXR instrumentation, though we expect that smaller flares will continue to be discovered as instrumental and observational techniques progress. The flare occurred during a solar observation by the highly sensitive NuSTAR astrophysical HXR spacecraft, which used its direct focusing optics to produce detailed flare spectra and images. The flare exhibits properties commonly observed in larger flares, including a fast rise and more gradual decay, and similar spatial dimensions to the RHESSI microflares. We will discuss the presence of non-thermal (flare-accelerated) electrons during the impulsive phase. The flare is small in emission measure, temperature, and energy, though not in physical dimensions. Its presence is an indication that flares do indeed scale down to smaller energies and retain what we customarily think of as “flarelike” properties.

  5. Backscatter, anisotropy, and polarization of solar hard X-rays

    NASA Technical Reports Server (NTRS)

    Bai, T.; Ramaty, R.

    1978-01-01

    The problems of anisotropy, polarization, center-to-limb variation of the X-ray spectrum, and Compton backscatter are investigated in a study of solar hard X-rays. Effect of backscatter are found particularly important for anisotropic sources which emit hard X-rays predominantly toward the photosphere; for such anisotropic primary X-ray sources, the observed X-ray flux near 30 keV does not depend significantly on the position of the flare. In addition, the degree of polarization of the sum of the primary and reflected X-rays with energies in the 15 to 30 keV range may be as high as 30%. Determination of the height and anisotropy of the primary X-ray sources from study of the albedo patch is also discussed.

  6. FY06 LDRD Final Report Next-generation x-ray optics: focusing hard x-rays

    SciTech Connect

    Pivovaroff, M; Soufli, R

    2007-03-01

    The original goal of our research was to open up a new class of scientific experiments by increasing the power of newly available x-ray sources by orders of magnitude. This was accomplished by developing a new generation of x-ray optics, based on hard x-ray (10-200 keV) reflective and diffractive focusing elements. The optical systems we envision begin with a core reflective optic, which has the ability to capture and concentrate x-rays across a wide range of energies and angles band, combined with diffractive optics, based on large-scale multilayer structures, that will further enhance the spatial, spectral and temporal resolving power of the system. Enabling technologies developed at LLNL such as precise mounting of thermally formed substrates, smoothing techniques and multilayer films of ultra-high reflectance and precision were crucial in the development and demonstration of our research objectives. Highlights of this phase of the project include: the design and fabrication of a concentrator optic for the Pleiades Thomson X-ray source located at LLNL, smoothing of glass substrates through application of polyimide films, and the design, fabrication and testing of novel volume multilayers structures. Part of our research into substrate smooth led to the development of a new technique (patent pending) to construct high-quality, inexpensive x-ray optics. This innovation resulted in LLNL constructing a x-ray optic for the CERN Axion Solar Telescope (CAST) and allowed LLNL to join the international experiment.

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

    NASA Technical Reports Server (NTRS)

    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.

  8. The development of hard x-ray optics at MSFC

    NASA Astrophysics Data System (ADS)

    Ramsey, Brian D.; Elsner, Ron F.; Engelhaupt, Darell; Gubarev, Mikhail V.; Kolodziejczak, Jeffery J.; O'Dell, Stephen L.; Speegle, Chet O.; Weisskopf, Martin C.

    2004-02-01

    We have developed the electroformed-nickel replication process to enable us to fabricate light-weight, high-quality mirrors for the hard-x-ray region. Two projects currently utilizing this technology are the production of 240 mirror shells, of diameters ranging from 50 to 94 mm, for our HERO balloon payload, and 150- and 230-mm-diameter shells for a prototype Constellation-X hard-x-ray telescope module. The challenge for the former is to fabricate, mount, align and fly a large number of high-resolution mirrors within the constraints of a modest budget. For the latter, the challenge is to maintain high angular resolution despite weight-budget-driven mirror shell thicknesses (100 μm) which make the shells extremely sensitive to fabrication and handling stresses, and to ensure that the replication process does not degrade the ultra-smooth surface finish (~3 Å) required for eventual multilayer coatings. We present a progress report on these two programs.

  9. "X-Ray Transients in Star-Forming Regions" and "Hard X-Ray Emission from X-Ray Bursters"

    NASA Technical Reports Server (NTRS)

    Halpern, Jules P.; Kaaret, Philip

    1999-01-01

    This grant funded work on the analysis of data obtained with the Burst and Transient Experiment (BATSE) on the Compton Gamma-Ray Observatory. The goal of the work was to search for hard x-ray transients in star forming regions using the all-sky hard x-ray monitoring capability of BATSE. Our initial work lead to the discovery of a hard x-ray transient, GRO J1849-03. Follow-up observations of this source made with the Wide Field Camera on BeppoSAX showed that the source should be identified with the previously known x-ray pulsar GS 1843-02 which itself is identified with the x-ray source X1845-024 originally discovered with the SAS-3 satellite. Our identification of the source and measurement of the outburst recurrence time, lead to the identification of the source as a Be/X-ray binary with a spin period of 94.8 s and an orbital period of 241 days. The funding was used primarily for partial salary and travel support for John Tomsick, then a graduate student at Columbia University. John Tomsick, now Dr. Tomsick, received his Ph.D. from Columbia University in July 1999, based partially on results obtained under this investigation. He is now a postdoctoral research scientist at the University of California, San Diego.

  10. X-ray properties of hard X-ray Cataclysmic Variables

    NASA Astrophysics Data System (ADS)

    de Martino, D.; Bernardini, F.; Mukai, K.; Falanga, M.

    2014-07-01

    Among hard X-ray galactic sources detected by the INTEGRAL and SWIFT surveys, those identified as accreting white dwarf binaries recently boosted in number, representing ~20% of the galactic sample. The majority are identified as magnetic Cataclysmic Variables (CVs) suggesting that this subclass is an important costituent of galactic population of X-ray sources. We will present the results of an on-going follow-up programme with XMM-Newton aiming at identifying the true nature of newly discovered hard X-ray CV candidates.

  11. Hard x-ray imaging system for XEUS

    NASA Astrophysics Data System (ADS)

    Kunieda, Hideyo; Takahashi, Tadayuki; Kokubun, Motohide; Nakazawa, Kazuhiro; Ogasaka, Yasushi

    2008-07-01

    One of the major sciences of XEUS is the evolution of massive black holes from early to current Universe. As is well known, considerable fraction of massive black holes harbored in active galactic nuclei are embedded in thick absorbing material. In order to observe black holes without any bias of absorption, we propose a hard X-ray imaging system to XEUS. The hard X-ray imaging system is consisted of super mirror X-ray telescopes with multilayer coating and of the position sensitive hard X-ray imaging CdTe detector. Under the current boundary conditions, the design parameters will be optimized for the telescope and the multilayers. Current achievements of hard X-ray imaging detectors are also presented.

  12. Demonstration of X-ray linear dichroism imaging with hard X-rays.

    PubMed

    Sato, K; Okitsu, K; Ueji, Y; Matsushita, T; Amemiya, Y

    2000-11-01

    X-ray polarization-contrast images resulting from X-ray linear dichroism (XLD) in the hard X-ray region have been successfully recorded for the first time. The apparatus used consisted of an X-ray polarizer, double X-ray phase retarders and a high-spatial-resolution X-ray charge-coupled device (CCD) detector. The sample used was a hexagonal close packed (h.c.p.) cobalt single-crystal foil of thickness about 12 microm. The experiment was performed at X-ray energies of 23 and 29 eV above the cobalt K edge (7709 eV), at which the maximum linear dichroisms (approximately 3%) were observed, with their signs reversed, in the XLD spectrum measured with quadruple X-ray phase retarders. The contrasts in the images at the two X-ray energies were reversed as a result of the XLD in the sample. Furthermore, the values of the contrast in the images arising from the linear dichroism (approximately 3%) were in good agreement with those yielded by the XLD spectrum. PMID:16609223

  13. Hard X-ray polarimetry with Astrosat-CZTI

    NASA Astrophysics Data System (ADS)

    Vadawale, S. V.; Chattopadhyay, T.; Rao, A. R.; Bhattacharya, D.; Bhalerao, V. B.; Vagshette, N.; Pawar, P.; Sreekumar, S.

    2015-06-01

    X-ray polarimetry is largely an unexplored area of an otherwise mature field of X-ray astronomy. Except for a few early attempts during the 1970s, no dedicated X-ray polarimeter has been flown during the past four decades. On the other hand, the scientific value of X-ray polarization measurement has been well known for a long time, and there has been significant technical progress in developing sensitive X-ray polarimeters in recent years. But there are no approved dedicated X-ray polarimetric experiments to be flown in the near future, so it is important to explore the polarimetric capabilities of other existing or planned instruments and examine whether they can provide significant astrophysical polarization measurements. In this paper, we present experimental results to show that the CZTI instrument onboard the forthcoming Indian astronomy mission, Astrosat, will be able to provide sensitive measurements of X-ray polarization in the energy range of 100-300 keV. CZTI will be able to constrain any intrinsic polarization greater than ~40% for bright X-ray sources (>500 mCrab) within a short exposure of ~100 ks with a 3-sigma confidence level. We show that this seemingly "modest" sensitivity can play a very significant role in addressing long pending questions, such as the contribution of relativistic jets to hard X-rays in black hole binaries and X-ray emission mechanism and geometry in X-ray pulsars.

  14. Hard X-Ray, Soft X-Ray, and EUV Studies of Solar Eruptions

    NASA Technical Reports Server (NTRS)

    Sterling, Alphonse C.; Wagner, William (Technical Monitor)

    2003-01-01

    Document study the hard X-ray (HXR), soft X-ray (SXR) ,EUV, and magnetic nature of solar eruptions, with the objective of elucidating the physics of the eruption process. In particular, it was examine the viability of two specific eruption mechanisms, detailed in our proposal. These mechanisms are the "breakout model", and the "tether cutting model". During the second year, it was a significant progress in the goals to Data Sets Utilized. In the publications during this second year of the grant period, the data was used from the E W Imaging Telescope (EIT) and the Michelson Doppler Imager (MDI) instruments on SOHO, and from the Soft X-ray Telescope (SXT), Hard X-ray Telescope (HXT), and the Bragg Crystal Spectrometer (BCS) on Yooh.

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

    SciTech Connect

    Vasudevan, Ranjan V.; Mushotzky, Richard F.; Reynolds, Christopher S.; Lohfink, Anne M.; Zoghbi, Abderahmen; Fabian, Andrew C.; Gallo, Luigi C.; Walton, Dominic

    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.

  16. Using compound kinoform hard-x-ray lenses to exceed the critical angle limit.

    PubMed

    Evans-Lutterodt, K; Stein, A; Ablett, J M; Bozovic, N; Taylor, A; Tennant, D M

    2007-09-28

    We have fabricated and tested a compound lens consisting of an array of four kinoform lenses for hard x-ray photons of 11.3 keV. Our data demonstrate that it is possible to exceed the critical angle limit by using multiple lenses, while retaining lens function, and this suggests a route to practical focusing optics for hard x-ray photons with nanometer scale resolution and below. PMID:17930597

  17. Using Compound Kinoform Hard-X-Ray Lenses to Exceed the Critical Angle Limit

    SciTech Connect

    Evans-Lutterodt, K.; Stein, A.; Ablett, J. M.; Bozovic, N.; Taylor, A.; Tennant, D. M.

    2007-09-28

    We have fabricated and tested a compound lens consisting of an array of four kinoform lenses for hard x-ray photons of 11.3 keV. Our data demonstrate that it is possible to exceed the critical angle limit by using multiple lenses, while retaining lens function, and this suggests a route to practical focusing optics for hard x-ray photons with nanometer scale resolution and below.

  18. Aperiodic Mo/Si multilayers for hard x-rays.

    PubMed

    Pardini, Tom; Alameda, Jennifer; Platonov, Yuriy; Robinson, Jeff; Soufli, Regina; Spiller, Eberhard; Walton, Chris; Hau-Riege, Stefan P

    2016-08-01

    In this work we have developed aperiodic Molybdenum/Silicon (Mo/Si) multilayers (MLs) to reflect 16.25 keV photons at a grazing angle of incidence of 0.6° ± 0.05°. To the best of our knowledge this is the first time this material system has been used to fabricate aperiodic MLs for hard x-rays. At these energies new hurdles arise. First of all a large number of bilayers is required to reach saturation. This poses a challenge from the manufacturing point of view, as thickness control of each ML period becomes paramount. The latter is not well defined a priori, due to the thickness of the interfacial silicide layers which has been observed to vary as a function of Mo and Si thickness. Additionally an amorphous-to-crystalline transition for Mo must be avoided in order maintain reasonably low roughness at the interfaces. This transition is well within the range of thicknesses pertinent to this study. Despite these difficulties our data demonstrates that we achieved reasonably flat ML response across the angular acceptance of ± 0.05°, with an experimentally confirmed average reflectivity of 28%. Such a ML prescription is well suited for applications in the field of hard x-ray imaging of highly diverging sources. PMID:27505826

  19. Prepulse dependence in hard x-ray generation from microdroplets

    SciTech Connect

    Anand, M.; Kahaly, S.; Kumar, G. Ravindra; Sandhu, A. S.; Gibbon, P.; Krishnamurthy, M.

    2006-04-07

    We report on experiments which show that liquid microdroplets are very efficient in hard x-ray generation. We make a comparative study of hard x-ray emission from 15 {mu}m methanol microdroplets and a plain slab target of similar atomic composition at similar laser intensities. The hard X-ray yield from droplet plasmas is about 35 times more than that obtained from solid plasmas. A prepulse that is about 10ns and at least 2% in intensity of the main pulse is essential for hard x-ray generation from the droplets at about 1015 W cm-2. A hot electron temperature of 36 keV is measured from the droplets at 8 x 1014 W cm-2; three times higher intensity is needed to obtain similar hot electron temperature from solid plasmas that have similar atomic composition. We use 1D-PIC simulation to obtain qualitative correlation to the experimental observations.

  20. Direct-write X-ray lithography using a hard X-ray Fresnel zone plate.

    PubMed

    Lee, Su Yong; Noh, Do Young; Lee, Hae Cheol; Yu, Chung-Jong; Hwu, Yeukuang; Kang, Hyon Chol

    2015-05-01

    Results are reported of direct-write X-ray lithography using a hard X-ray beam focused by a Fresnel zone plate with an outermost zone width of 40 nm. An X-ray beam at 7.5 keV focused to a nano-spot was employed to write arbitrary patterns on a photoresist thin film with a resolution better than 25 nm. The resulting pattern dimension depended significantly on the kind of underlying substrate, which was attributed to the lateral spread of electrons generated during X-ray irradiation. The proximity effect originated from the diffuse scattering near the focus and electron blur was also observed, which led to an increase in pattern dimension. Since focusing hard X-rays to below a 10 nm spot is currently available, the direct-write hard X-ray lithography developed in this work has the potential to be a promising future lithographic method. PMID:25931097

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

    PubMed Central

    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

    2012-01-01

    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. PMID:23093770

  2. The Hard X-Ray Sky: Recent Observational Progress

    NASA Technical Reports Server (NTRS)

    Gehrels, Neil; Cannizzo, John K.

    2010-01-01

    The last fifty years have witnessed the birth, development, and maturation to full potential of hard X-ray astrophysics. The primary force driving the history of the field has been the development of space-based instrumentation optimized for getting the maximum science out of observations of high-energy photons from astrophysical sources. Hard X-ray telescopes are leading research in areas such as galactic diffuse emission, galactic transients, and active galactic nuclei.

  3. Advancements in hard x-ray multilayers for x-ray astronomy

    NASA Astrophysics Data System (ADS)

    Windt, David L.

    2015-09-01

    This paper is focused on recent progress in the development of broad-band multilayer coatings designed for hard X-ray energies, for use in future astronomical telescopes. We describe a new laboratory-based hard X-ray reflectometer for atwavelength characterization of multilayer films, we present the results of an experimental comparison of the hard X-ray performance of several W-based periodic multilayer coatings, and we describe the optimization and experimental performance of new non-periodic Co-based multilayer coatings (both depth-graded and aperiodic), designed for continuous response through the W and Pt K-edges near 70 and 80 keV, respectively. We discuss future research directions in light of these new results.

  4. A transmissive x-ray polarimeter design for hard x-ray focusing telescopes

    NASA Astrophysics Data System (ADS)

    Li, Hong; Feng, Hua; Ji, Jianfeng; Deng, Zhi; He, Li; Zeng, Ming; Li, Tenglin; Liu, Yinong; Heng, Peiying; Wu, Qiong; Han, Dong; Dong, Yongwei; Lu, Fangjun; Zhang, Shuangnan

    2015-08-01

    The X-ray Timing and Polarization (XTP) is a mission concept for a future space borne X-ray observatory and is currently selected for early phase study. We present a new design of X-ray polarimeter based on the time projection gas chamber. The polarimeter, placed above the focal plane, has an additional rear window that allows hard X-rays to penetrate (a transmission of nearly 80% at 6 keV) through it and reach the detector on the focal plane. Such a design is to compensate the low detection efficiency of gas detectors, at a low cost of sensitivity, and can maximize the science return of multilayer hard X-ray telescopes without the risk of moving focal plane instruments. The sensitivity in terms of minimum detectable polarization, based on current instrument configuration, is expected to be 3% for a 1mCrab source given an observing time of 105 s. We present preliminary test results, including photoelectron tracks and modulation curves, using a test chamber and polarized X-ray sources in the lab.

  5. Unbeamed tidal disruption events at hard X-rays

    NASA Astrophysics Data System (ADS)

    Hryniewicz, K.; Walter, R.

    2016-02-01

    Context. Owing to their thermal emission, tidal disruption events (TDEs) were regularly detected in the soft X-rays and sometimes in the optical. Only a few TDEs have been detected at hard X-rays: two are high redshift beamed events, one of which occurred at the core of a nearby galaxy, and the most recent one is of a different nature, involving a compact object in the Milky Way. Aims: The aims of this work are to obtain a first sample of hard X-ray-selected unbeamed TDEs, to determine their frequency and to probe whether TDEs usually or exceptionally emit at hard X-ray energies. Methods: We performed extensive searches for hard X-ray flares at positions in over 53 000 galaxies, up to a distance of 100 Mpc in the Swift/BAT archive. Light curves were extracted and parametrized. The quiescent hard X-ray emission was used to exclude persistently active galactic nuclei. Significant flares from non-active galaxies were derived and checked for possible contamination. Results: We found a sample of nine TDE candidates, which translates into a rate of 2 × 10-5 galaxy-1 yr-1 above the BAT detection limit. This rate is consistent with those observed by XMM-Newton at soft X-rays and in the optical from SDSS observations, and is as expected from simulations. We conclude that hard X-ray emission should be ubiquitous in un-beamed TDEs and that electrons should be accelerated in their accretion flow.

  6. Hard X-ray Pump, X-ray Probe Spectroscopy of Single Crystals

    NASA Astrophysics Data System (ADS)

    Loether, Aaron; Decamp, Matt; Walko, Donald

    Recent advancements in intense x-ray pulses have made it possible to perform hard x-ray pump probe spectroscopy. Inspired by optical pump probe, we've built a retroreflector for use with synchrotron based x-rays, using Germanium crystals at Bragg condition in place of mirrors, to control relative timing of x-ray pulses and perform time resolved measurements. Testing of multiple versions of the retroreflector was done both experimentally and via simulation; the comparison allows us to show efficiencies achievable theoretically and realistically. A proof of concept time resolved diffraction experiment on a Germanium 111 crystal was performed utilizing high intensity broadband x-ray pulses and the resulting heating and propagated strains were measured by low intensity monochromatic x-ray pulses. This work was supported from the DOE-EPSCoR Grant No. DE-FG02-11ER46816. Use of the 178 Advanced Photon Source was supported by the U. S. Department of Energy, Office of Science, 179 Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.

  7. Hard x-ray Zernike microscopy reaches 30 nm resolution.

    SciTech Connect

    Chen, Y.; Chen, T.; Yi, J.; Chu, Y.; Lee, W.-K.; Wang, C.; Kempson, I.; Hwu, Y.; Gajdosik, V.; Margaritondo, G.

    2011-03-30

    Since its invention in 1930, Zernike phase contrast has been a pillar in optical microscopy and more recently in x-ray microscopy, in particular for low-absorption-contrast biological specimens. We experimentally demonstrate that hard-x-ray Zernike microscopy now reaches a lateral resolution below 30?nm while strongly enhancing the contrast, thus opening many new research opportunities in biomedicine and materials science.

  8. Hard x-ray Zernike Microscopy Reaches 30 nm Resolution

    SciTech Connect

    Chen, Y.T.; Chu, Y.; Chen, T-Y.; Yi, J.; Lee, W-K.; Wang, C-L.; Kempson, I. M.; Hwu, Y.; Gajdosik, V.; Margaritondo, G.

    2011-03-30

    Since its invention in 1930, Zernike phase contrast has been a pillar in optical microscopy and more recently in x-ray microscopy, in particular for low-absorption-contrast biological specimens. We experimentally demonstrate that hard-x-ray Zernike microscopy now reaches a lateral resolution below 30 nm while strongly enhancing the contrast, thus opening many new research opportunities in biomedicine and materials science.

  9. Generation of first hard X-ray pulse at Tsinghua Thomson Scattering X-ray Source.

    PubMed

    Du, Yingchao; Yan, Lixin; Hua, Jianfei; Du, Qiang; Zhang, Zhen; Li, Renkai; Qian, Houjun; Huang, Wenhui; Chen, Huaibi; Tang, Chuanxiang

    2013-05-01

    Tsinghua Thomson Scattering X-ray Source (TTX) is the first-of-its-kind dedicated hard X-ray source in China based on the Thomson scattering between a terawatt ultrashort laser and relativistic electron beams. In this paper, we report the experimental generation and characterization of the first hard X-ray pulses (51.7 keV) via head-on collision of an 800 nm laser and 46.7 MeV electron beams. The measured yield is 1.0 × 10(6) per pulse with an electron bunch charge of 200 pC and laser pulse energy of 300 mJ. The angular intensity distribution and energy spectra of the X-ray pulse are measured with an electron-multiplying charge-coupled device using a CsI scintillator and silicon attenuators. These measurements agree well with theoretical and simulation predictions. An imaging test using the X-ray pulse at the TTX is also presented. PMID:23742539

  10. Generation of first hard X-ray pulse at Tsinghua Thomson Scattering X-ray Source

    SciTech Connect

    Du Yingchao; Yan Lixin; Hua Jianfei; Du Qiang; Zhang Zhen; Li Renkai; Qian Houjun; Huang Wenhui; Chen Huaibi; Tang Chuanxiang

    2013-05-15

    Tsinghua Thomson Scattering X-ray Source (TTX) is the first-of-its-kind dedicated hard X-ray source in China based on the Thomson scattering between a terawatt ultrashort laser and relativistic electron beams. In this paper, we report the experimental generation and characterization of the first hard X-ray pulses (51.7 keV) via head-on collision of an 800 nm laser and 46.7 MeV electron beams. The measured yield is 1.0 Multiplication-Sign 10{sup 6} per pulse with an electron bunch charge of 200 pC and laser pulse energy of 300 mJ. The angular intensity distribution and energy spectra of the X-ray pulse are measured with an electron-multiplying charge-coupled device using a CsI scintillator and silicon attenuators. These measurements agree well with theoretical and simulation predictions. An imaging test using the X-ray pulse at the TTX is also presented.

  11. Beyond hard x-ray photoelectron spectroscopy: Simultaneous combination with x-ray diffraction

    SciTech Connect

    Rubio-Zuazo, Juan; Castro, German R.

    2013-05-15

    Hard x-ray photoelectron spectroscopy (HAXPES) is a powerful and novel emerging technique for the nondestructive determination of electronic properties and chemical composition of bulk, buried interfaces and surfaces. It benefits from the exceptionally large escape depth of high kinetic energy photoelectrons, increasing the information depth up to several tens of nanometers. Complementing HAXPES with an atomic structure sensitive technique (such as x-ray diffraction) opens a new research field with major applications for materials science. At SpLine, the Spanish CRG beamline at the European Synchrotron Radiation Facility, we have developed a novel experimental set-up that combines HAXPES and x-ray diffraction (x-ray reflectivity, surface x-ray diffraction, grazing incidence x-ray diffraction, and reciprocal space maps). Both techniques can be operated simultaneously on the same sample and using the same excitation source. The set-up includes a robust 2S + 3D diffractometer hosting a ultrahigh vacuum chamber equipped with a unique photoelectron spectrometer (few eV < electron kinetic energy < 15 keV), x-ray tube (Mg/Ti), 15 keV electron gun, and auxiliary standard surface facilities (molecular beam epitaxy evaporator, ion gun, low energy electron diffraction, sample heating/cooling system, leak valves, load-lock sample transfer, etc.). This end-station offers the unique possibility of performing simultaneous HAXPES + x-ray diffraction studies. In the present work, we describe the experimental set-up together with two experimental examples that emphasize its outstanding capabilities: (i) nondestructive characterization of the Si/Ge and HfO{sub 2}/SiO{sub 2} interfaces on Ge-based CMOS devices, and (ii) strain study on La{sub 0.7}Ca{sub 0.3}MnO{sub 3} ultrathin films grown on SrTiO{sub 3}(001) substrate.

  12. Magnetic circular dichroism in the hard X-ray range

    NASA Astrophysics Data System (ADS)

    Rogalev, A.; Wilhelm, F.

    2015-12-01

    An overview of X-ray magnetic circular dichroism (XMCD) spectroscopy in the hard X-ray range is presented. A short historical overview shows how this technique has evolved from the early days of X-ray physics to become a workhorse technique in the modern magnetism research As with all X-ray spectroscopies, XMCD has the advantage of being element specific. Interpretation of the spectra based on magneto-optical sum rules can provide unique information about spin and orbital moment carried by absorbing atom in both amplitude and direction, can infer magnetic interactions from element selective magnetization curves, can allow separation of magnetic and non-magnetic components in heterogeneous systems. The review details the technology currently available for XMCD measurements in the hard X-ray range referring to the ESRF beamline ID12 as an example. The strengths of hard X-ray magnetic circular dichroism technique are illustrated with a wide variety of representative examples, such as actinide based ferromagnets, paramagnetism in metals, pure metallic nanoparticles, exchange spring magnets, half metallic ferromagnets, magnetism at interfaces, and dilute magnetic semiconductors. In this way, we aim to encourage researchers from various scientific communities to consider XMCD as a tool to understanding the electronic and magnetic properties of their samples.

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

    DOEpatents

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

    1995-01-17

    A process is disclosed for fabricating high efficiency x-ray lenses that operate in the 0.5-4.0 keV region suitable for use in biological imaging, surface science, and x-ray lithography of integrated circuits. The gradient index x-ray optics fabrication process broadly involves co-sputtering multi-layers of film on a wire, followed by slicing and mounting on block, and then ion beam thinning to a thickness determined by periodic testing for efficiency. The process enables the fabrication of transmissive gradient index x-ray optics for the 0.5-4.0 keV energy range. This process allows the fabrication of optical elements for the next generation of imaging and x-ray lithography instruments in the soft x-ray region. 13 figures.

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

    DOEpatents

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

    1995-01-01

    A process for fabricating high efficiency x-ray lenses that operate in the 0.5-4.0 keV region suitable for use in biological imaging, surface science, and x-ray lithography of integrated circuits. The gradient index x-ray optics fabrication process broadly involves co-sputtering multi-layers of film on a wire, followed by slicing and mounting on block, and then ion beam thinning to a thickness determined by periodic testing for efficiency. The process enables the fabrication of transmissive gradient index x-ray optics for the 0.5-4.0 keV energy range. This process allows the fabrication of optical elements for the next generation of imaging and x-ray lithography instruments m the soft x-ray region.

  15. Enhanced hard x-ray emission from microdroplet preplasma

    SciTech Connect

    Anand, M.; Kahaly, S.; Ravindra Kumar, G.; Krishnamurthy, M.; Sandhu, A.S.; Gibbon, P.

    2006-05-01

    We perform a comparative study of hard x-ray emission from femtosecond laser plasmas in 15 {mu}m methanol microdroplets and Perspex target. The hard x-ray yield from droplet plasmas is {approx_equal}68 times more than that obtained from solid plasmas at 2x10{sup 15} W cm{sup -2}. A 10 ns prepulse at about 5% of the main pulse appears to be essential for hard x-ray generation from droplets. Hot electron temperature of 36 keV is measured from the droplets at 8x10{sup 14} W cm{sup -2}, whereas a three times higher intensity is needed to obtain similar hot electron temperatures from Perspex plasmas. Particle-in-cell simulations with very long scale-length density profiles support experimental observations.

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

    SciTech Connect

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

    2015-05-04

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

  17. Hard x-ray spectrometers for NIF (abstract)

    NASA Astrophysics Data System (ADS)

    Seely, John; Holland, Glenn; Brown, Charles; Deslattes, Richard; Hudson, Lawrence; Bell, Perry; Miller, Michael; Back, Christina

    2001-01-01

    A National Ignition Facility (NIF) core diagnostic instrument has been designed and will be fabricated to record x-ray spectra in the 1.2-20 keV energy range. The high-energy electronic x-ray instrument has four reflection crystals with overlapping coverage of 1.2-10.9 keV and one transmission crystal covering 8.6-20 keV. The spectral resolving power varies from approximately 1000 at low energies to 315 at 20 keV. The spectrum produced by each crystal is recorded by a modified commercial dental x-ray charge coupled device (CCD) detector. The scintillators on the CCD detectors are optimized for the energy ranges. A one-channel x-ray spectrometer, using one transmission crystal covering 12-60 keV, will be fabricated for the OMEGA laser facility. The transmission crystal spectrometers are based on instruments originally designed at National Institute for Standards and Technology for the purpose of characterizing the x-ray flux from medical radiography sources. Utilizing one of those instruments and a commercial dental x-ray CCD detector, x-ray images were recorded using a single pulse from a laboratory x-ray source with a peak charging voltage of 200 kV. A resolving power of 300 was demonstrated by recording on film the Kα1 and Kα2 characteristic x-ray lines near 17 keV from a molybdenum anode. The continuum radiation from a tungsten anode was recorded in the 20-50 keV energy range. The transmission crystal spectrometer has sufficient spectral resolution and sensitivity to record the line and continuum radiation from high-Z targets irradiated by the NIF laser and the OMEGA laser.

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

    NASA Astrophysics Data System (ADS)

    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.

  19. Hard X-Ray And Wide Focusing Telescopes

    NASA Technical Reports Server (NTRS)

    Gorenstein, Paul; Johnson, William B. (Technical Monitor)

    2001-01-01

    The development of a hard X-ray telescope requires new technology for both substrates and coatings. Our activities in these two areas were carried out virtually in parallel during most of the past few years. They are converging on the production of our first integral conical, substrate electroformed mirror that will be coated with a graded d-spacing multilayer. Its imaging properties and effective area will be measured in hard X-ray beams. We discuss each of these activities separately in the following two sections.

  20. Towards hard X-ray imaging at GHz frame rate

    SciTech Connect

    Wang, Zhehui; Morris, Christopher; Luo, Shengnian; Kwiatkowski, Kris K.; Kapustinsky, Jon S.

    2012-05-02

    Gigahertz (GHz) imaging using hard X-rays ({approx}> 10 keV) can be useful to high-temperature plasma experiments, as well as research using coherent photons from synchrotron radiation and X-ray free electron lasers. GHz framing rate can be achieved by using multiple cameras through multiplexing. The advantages and trade-offs of single-photon detection mode, when no more than one X-ray photon is detected per pixel, are given. Two possible paths towards X-ray imaging at GHz frame rates using a single camera are (a) Avalanche photodiode arrays of high-Z materials and (b) Microchannel plate photomultipliers in conjunction with materials with large indices of refraction.

  1. Towards hard x-ray imaging at GHz frame rate

    SciTech Connect

    Wang Zhehui; Morris, C. L.; Kapustinsky, J. S.; Kwiatkowski, K.; Luo, S.-N.

    2012-10-15

    Gigahertz (GHz) imaging using hard x-rays ( Greater-Than-Or-Equivalent-To 10 keV) can be useful to high-temperature plasma experiments, as well as research and applications using coherent photons from synchrotron radiation and x-ray free electron lasers. GHz framing rate can be achieved by using multiple cameras through multiplexing. The advantages and trade-offs of single-photon detection mode, when no more than one x-ray photon is detected per pixel, are given. Two possible paths towards x-ray imaging at GHz frame rates using a single camera are: (a) avalanche photodiode arrays of high-Z materials and (b) microchannel plate photomultipliers in conjunction with materials with large indices of refraction.

  2. Thermal models for solar hard X-ray bursts

    NASA Technical Reports Server (NTRS)

    Smith, D. F.; Auer, L. H.

    1980-01-01

    Thermal models for hard X-ray bursts consisting of a one-dimensional flux tube whose central electrons are heated to about 400 million K are examined. It is found that the evolution of a thermal X-ray source is a sensitive function of the electron-ion thermal coupling and the state of the plasma into which the source expands. When this coupling is weak, the heated electrons separate into a region of high temperature of about 400 million K and a region of lower temperature of about 100 million K, a process which leads to a power-law X-ray spectrum. In the case of strong coupling there is only one dominant temperature, about 200 million K, and the X-ray spectrum resembles a true thermal spectrum.

  3. Observational Aspects of Hard X-ray Polarimetry

    NASA Astrophysics Data System (ADS)

    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. The EXOSS mission for hard X-ray astronomy

    NASA Technical Reports Server (NTRS)

    Grindlay, Jonathan E.; Prince, Thomas A.; Weisskopf, M.; Skinner, G.

    1990-01-01

    The basis for the Energetic X-ray Observatory on Space Station is described. Attention is given to the principal scientific objectives of EXOSS, namely, to study in detail AGN and quasars (some 10,000 should be detectable) as well as compact Galactic sources (accreting white dwarfs, neutron stars, and black holes), and to probe both nonthermal and high-temperature thermal phenomena and the fundamental nature of these objects. The principal technical characteristics of the EXOSS baseline instrument, which overlap in sensitivity in the approximately 40-to-60-keV band, are presented. EXOSS should facilitate efforts to determine: the central power source and the dominant emission mechanisms in AGN, the ways in which the various AGN classes differ as hard X-ray and soft gamma-ray emitters, and the contribution of AGN to the diffuse hard X-ray and soft gamma-ray background.

  5. A Hard X-Ray Telescope Science Enhancement Package for the Constellation X-Ray Mission

    NASA Technical Reports Server (NTRS)

    Ramsey, Brian; Gorenstein, Paul

    2007-01-01

    Details of a hard-x-ray science enhancement package for the Constellation-X mission are presented. A scientific case is made for the inclusion of such an instrument on the planned mission and a detailed design is presented that will satisfy science requirements yet fall within the ground rules for enhancement packages: a cost of less than $100M and a mass of no more than 100 kg.

  6. Crab Nebula Variations in Hard X-rays

    NASA Technical Reports Server (NTRS)

    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

  7. Nanoplasma Formation by High Intensity Hard X-rays

    PubMed Central

    Tachibana, T.; Jurek, Z.; Fukuzawa, H.; Motomura, K.; Nagaya, K.; Wada, S.; Johnsson, P.; Siano, M.; Mondal, S.; Ito, Y.; Kimura, M.; Sakai, T.; Matsunami, K.; Hayashita, H.; Kajikawa, J.; Liu, X.-J.; Robert, E.; Miron, C.; Feifel, R.; Marangos, J. P.; Tono, K.; Inubushi, Y.; Yabashi, M.; Son, S.-K.; Ziaja, B.; Yao, M.; Santra, R.; Ueda, K.

    2015-01-01

    Using electron spectroscopy, we have investigated nanoplasma formation from noble gas clusters exposed to high-intensity hard-x-ray pulses at ~5 keV. Our experiment was carried out at the SPring-8 Angstrom Compact free electron LAser (SACLA) facility in Japan. Dedicated theoretical simulations were performed with the molecular dynamics tool XMDYN. We found that in this unprecedented wavelength regime nanoplasma formation is a highly indirect process. In the argon clusters investigated, nanoplasma is mainly formed through secondary electron cascading initiated by slow Auger electrons. Energy is distributed within the sample entirely through Auger processes and secondary electron cascading following photoabsorption, as in the hard x-ray regime there is no direct energy transfer from the field to the plasma. This plasma formation mechanism is specific to the hard-x-ray regime and may, thus, also be important for XFEL-based molecular imaging studies. In xenon clusters, photo- and Auger electrons contribute more significantly to the nanoplasma formation. Good agreement between experiment and simulations validates our modelling approach. This has wide-ranging implications for our ability to quantitatively predict the behavior of complex molecular systems irradiated by high-intensity hard x-rays. PMID:26077863

  8. Characterization of New Hard X-ray Cataclysmic Variables

    NASA Technical Reports Server (NTRS)

    Bernardini, F.; deMartino, D.; Falanga, M.; Mukai, K.; Matt, G.; Bonnet-Bidaud, J.-M.; Masetti, N.; Mouchet, M.

    2012-01-01

    Aims. We aim at characterizing a sample of nine new hard X-ray selected Cataclysmic Variable (CVs), to unambiguously identify them as magnetic systems of the Intermediate Polar (IP) type. Methods. We performed detailed timing and spectral analysis by using X-ray, and simultaneous UV and optical data collected by XMM-Newton, complemented with hard X-ray data provided by INTEGRAL and Swift. The pulse arrival time were used to estimate the orbital periods. The broad band X-ray spectra were fitted using composite models consisting of different absorbing columns and emission components. Results. Strong X-ray pulses at the White Dwarf (WD) spin period are detected and found to decrease with energy. Most sources are spin-dominated systems in the X-rays, though four are beat dominated at optical wavelengths. We estimated the orbital period in all system (except for IGR J16500-3307), providing the first estimate for IGRJ08390-4833, IGRJ18308-1232, and IGR J18173-2509. All X-ray spectra are multi-temperature. V2069 Cyg and RX J0636+3535 poses a soft X-ray optically thick component at kT approx. 80 eV. An intense K (sub alpha) Fe line at 6.4 keV is detected in all sources. An absorption edge at 0.76 keV from OVII is detected in IGR J08390-4833. The WD masses and lower limits to the accretion rates are also estimated. Conclusions. We found all sources to be IPs. IGR J08390-4833, V2069 Cyg, and IGR J16500-3307 are pure disc accretors, while IGR J18308-1232, IGR J1509-6649, IGR J17195-4100, and RX J0636+3535 display a disc-overflow accretion mode. All sources show a temperature gradient in the post-shock regions and a highly absorbed emission from material located in the pre-shock flow which is also responsible for the X-ray pulsations. Reflection at the WD surface is likely the origin of the fluorescent iron line. There is an increasing evidence for the presence of a warm absorber in IPs, a feature that needs future exploration. The addition of two systems to the subgroup of

  9. Thin scintillators for ultrafast hard X-ray imaging

    NASA Astrophysics Data System (ADS)

    Wang, Zhehui; Barnes, Cris W.; Kapustinsky, Jon S.; Morris, Chris L.; Nelson, Ron O.; Yang, Fan; Zhang, Liyuan; Zhu, Ren-Yuan

    2015-05-01

    A multilayer thin-scintillator concept is described for ultrafast imaging. The individual layer thickness is determined by the spatial resolution and light attenuation length, the number of layers is determined by the overall efficiency. By coating the scintillators with a high quantum-efficiency photocathode, single X-ray photon detection can be achieved using fast scintillators with low light yield. The fast, efficient sensors, when combined with MCP and novel nanostructed electron amplification schemes, is a possible way towards GHz hard X-ray cameras for a few frames of images.

  10. Measurements of the hard-x-ray reflectivity of iridium

    SciTech Connect

    Romaine, S.; Bruni, R.; Gorenstein, P.; Zhong, Z

    2007-01-10

    In connection with the design of a hard-x-ray telescope for the Constellation X-Ray Observatory we measured the reflectivity of an iridium-coated zerodur substrate as a function of angle at 55, 60, 70, and 80 keV at the National Synchrotron Light Source of Brookhaven National Laboratory. The optical constants were derived from the reflectivity data. The real component of the index of refraction is in excellent agreement with theoretical values at all four energies. However, the imaginary component, which is related to the mass attenuation coefficient, is 50% to 70% larger at 55, 60, and 70 keV than theoretical values.

  11. Complete Hard X-Ray Surveys, AGN Luminosity Functions and the X-Ray Background

    NASA Technical Reports Server (NTRS)

    Tueller, Jack

    2011-01-01

    AGN are believed to make up most of the Cosmic X-Ray Background (CXB) above a few keV, but this background cannot be fully resolved at energies less than 10 keV due to absorption. The Swift/BAT and INTEGRAL missions are performing the first complete hard x-ray surveys with minimal bias due to absorption. The most recent results for both missions will be presented. Although the fraction of the CXB resolved by these surveys is small, it is possible to derive unbiased number counts and luminosity functions for AGN in the local universe. The survey energy range from 15-150 keV contains the important reflection and cutoff spectral features dominate the shape of the AGN contribution to the CXB. Average spectral characteristics of survey detected AGN will be presented and compared with model distributions. The numbers of hard x-ray blazars detected in these surveys are finally sufficient to estimate this important component's contribution the cosmic background. Constraints on CXB models and their significance will be discussed.

  12. Observational Aspects of Hard X-ray Polarimetry

    NASA Astrophysics Data System (ADS)

    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

  13. Discovery of Diffuse Hard X-ray Emission Around Jupiter

    NASA Astrophysics Data System (ADS)

    Ezoe, Yuichiro; Ishikawa, K.; Ohashi, T.; Terada, N.; Miyoshi, Y.; Uchiyama, Y.

    2009-09-01

    Our discovery of diffuse hard (1-5 keV) X-ray emission around Jupiter is reported. Recent Chandra and XMM-Newton observations revealed several types of X-rays in the vicinity of Jupiter such as auroral and disk emission from Jupiter and faint diffuse X-rays from the Io Plasma Torus (see Bhardwaj et al. 2007 for review). To investigate possible diffuse hard X-ray emission around Jupiter with the highest sensitivity, we conducted data analysis of Suzaku XIS observations of Jupiter on Feb 2006. After removing satellite and planetary orbital motions, we detected a significant diffuse X-ray emission extending to 6 x 3 arcmin with the 1-5 keV X-ray luminosity of 3e15 erg/s. The emitting region very well coincided with the Jupiter's radiation belts and the bright spot seemed to move according to the Io's motion. The 1-5 keV X-ray spectrum was represented by a simple power law model with a photon index of 1.4. Such a flat continuum strongly suggests non-thermal origin. We hence examined three mechanisms: bremsstrahlung by keV electrons, synchrotron emission by TeV electrons, and inverse Compton scattering of solar photons by MeV electrons. The former two can be rejected because of the X-ray spectral shape and implausible existence of TeV electrons around Jupiter, respectively. The last possibility was found to be possible because tens MeV electrons, which have been confirmed in inner radiation belts (Bolton et al. 2002), can kick solar photons to the keV energy range and provide a simple power-law continuum. We estimated an average electron density from the X-ray luminosity assuming the oblate spheroid shaped emitting region with 8 x 8 x 4 Jovian radii. The necessary density was 0.02 1/cm3 for 50 MeV electrons. Hence, our results may suggest a new particle acceleration phenomenon related to Io.

  14. Applications of Hard X-ray Full-Field Transmission X-ray Microscopy at SSRL

    SciTech Connect

    Liu, Y.; Andrews, J. C.; Mehta, A.; Pianetta, P.; Meirer, F.; Gil, S. Carrasco; Sciau, P.; Mester, Z.

    2011-09-09

    State-of-the-art hard x-ray full-field transmission x-ray microscopy (TXM) at beamline 6-2C of Stanford Synchrotron Radiation Lightsource has been applied to various research fields including biological, environmental, and material studies. With the capability of imaging a 32-micron field-of-view at 30-nm resolution using both absorption mode and Zernike phase contrast, the 3D morphology of yeast cells grown in gold-rich media was investigated. Quantitative evaluation of the absorption coefficient was performed for mercury nanoparticles in alfalfa roots exposed to mercury. Combining XANES and TXM, we also performed XANES-imaging on an ancient pottery sample from the Roman pottery workshop at LaGraufesenque (Aveyron).

  15. Applications of Hard X-ray Full-Field Transmission X-ray Microscopy at SSRL

    NASA Astrophysics Data System (ADS)

    Liu, Y.; Andrews, J. C.; Meirer, F.; Mehta, A.; Gil, S. Carrasco; Sciau, P.; Mester, Z.; Pianetta, P.

    2011-09-01

    State-of-the-art hard x-ray full-field transmission x-ray microscopy (TXM) at beamline 6-2C of Stanford Synchrotron Radiation Lightsource has been applied to various research fields including biological, environmental, and material studies. With the capability of imaging a 32-micron field-of-view at 30-nm resolution using both absorption mode and Zernike phase contrast, the 3D morphology of yeast cells grown in gold-rich media was investigated. Quantitative evaluation of the absorption coefficient was performed for mercury nanoparticles in alfalfa roots exposed to mercury. Combining XANES and TXM, we also performed XANES-imaging on an ancient pottery sample from the Roman pottery workshop at LaGraufesenque (Aveyron).

  16. ANS hard X-ray experiment development program. [emission from X-ray sources

    NASA Technical Reports Server (NTRS)

    Parsignault, D.; Gursky, H.; Frank, R.; Kubierschky, K.; Austin, G.; Paganetti, R.; Bawdekar, V.

    1974-01-01

    The hard X-ray (HXX) experiment is one of three experiments included in the Dutch Astronomical Netherlands Satellite, which was launched into orbit on 30 August 1974. The overall objective of the HXX experiment is the detailed study of the emission from known X-ray sources over the energy range 1.5-30keV. The instrument is capable of the following measurements: (1) spectral content over the full energy range with an energy resolution of approximately 20% and time resolution down to 4 seconds; (2) source time variability down to 4 milliseconds; (3) silicon emission lines at 1.86 and 2.00keV; (4) source location to a limit of one arc minute in ecliptic latitude; and (5) spatial structure with angular resolution of the arc minutes. Scientific aspects of experiment, engineering design and implementation of the experiment, and program history are included.

  17. Characterization of a 20-nm hard x-ray focus by ptychographic coherent diffractive imaging

    NASA Astrophysics Data System (ADS)

    Vila-Comamala, Joan; Diaz, Ana; Guizar-Sicairos, Manuel; Gorelick, Sergey; Guzenko, Vitaliy A.; Karvinen, Petri; Kewish, Cameron M.; Färm, Elina; Ritala, Mikko; Mantion, Alexandre; Bunk, Oliver; Menzel, Andreas; David, Christian

    2011-09-01

    Recent advances in the fabrication of diffractive X-ray optics have boosted hard X-ray microscopy into spatial resolutions of 30 nm and below. Here, we demonstrate the fabrication of zone-doubled Fresnel zone plates for multi-keV photon energies (4-12 keV) with outermost zone widths down to 20 nm. However, the characterization of such elements is not straightforward using conventional methods such as knife edge scans on well-characterized test objects. To overcome this limitation, we have used ptychographic coherent diffractive imaging to characterize a 20 nm-wide X-ray focus produced by a zone-doubled Fresnel zone plate at a photon energy of 6.2 keV. An ordinary scanning transmission X-ray microscope was modified to acquire the ptychographic data from a strongly scattering test object. The ptychographic algorithms allowed for the reconstruction of the image of the test object as well as for the reconstruction of the focused hard X-ray beam waist, with high spatial resolution and dynamic range. This method yields a full description of the focusing performance of the Fresnel zone plate and we demonstrate the usefulness ptychographic coherent diffractive imaging for metrology and alignment of nanofocusing diffractive X-ray lenses.

  18. Hard X-ray Imaging Polarimeter for PolariS

    NASA Astrophysics Data System (ADS)

    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.

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

    DOEpatents

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

    1997-10-21

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

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

    DOEpatents

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

    1997-10-21

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

  1. Spatial resolution of a hard x-ray CCD detector

    SciTech Connect

    Seely, John F.; Pereira, Nino R.; Weber, Bruce V.; Schumer, Joseph W.; Apruzese, John P.; Hudson, Lawrence T.; Szabo, Csilla I.; Boyer, Craig N.; Skirlo, Scott

    2010-08-10

    The spatial resolution of an x-ray CCD detector was determined from the widths of the tungsten x-ray lines in the spectrum formed by a crystal spectrometer in the 58 to 70 keV energy range. The detector had 20{mu}m pixel, 1700 by 1200 pixel format, and a CsI x-ray conversion scintillator. The spectral lines from a megavolt x-ray generator were focused on the spectrometer's Rowland circle by a curved transmission crystal. The line shapes were Lorentzian with an average width after removal of the natural and instrumental line widths of 95{mu}m (4.75 pixels). A high spatial frequency background, primarily resulting from scattered gamma rays, was removed from the spectral image by Fourier analysis. The spectral lines, having low spatial frequency in the direction perpendicular to the dispersion, were enhanced by partially removing the Lorentzian line shape and by fitting Lorentzian curves to broad unresolved spectral features. This demonstrates the ability to improve the spectral resolution of hard x-ray spectra that are recorded by a CCD detector with well-characterized intrinsic spatial resolution.

  2. High resolution double-sided diffractive optics for hard X-ray microscopy.

    PubMed

    Mohacsi, Istvan; Vartiainen, Ismo; Guizar-Sicairos, Manuel; Karvinen, Petri; Guzenko, Vitaliy A; Müller, Elisabeth; Färm, Elina; Ritala, Mikko; Kewish, Cameron M; Somogyi, Andrea; David, Christian

    2015-01-26

    The fabrication of high aspect ratio metallic nanostructures is crucial for the production of efficient diffractive X-ray optics in the hard X-ray range. We present a novel method to increase their structure height via the double-sided patterning of the support membrane. In transmission, the two Fresnel zone plates on the two sides of the substrate will act as a single zone plate with added structure height. The presented double-sided zone plates with 30 nm smallest zone width offer up to 9.9% focusing efficiency at 9 keV, that results in a factor of two improvement over their previously demonstrated single-sided counterparts. The increase in efficiency paves the way to speed up X-ray microscopy measurements and allows the more efficient utilization of the flux in full-field X-ray microscopy. PMID:25835837

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

    SciTech Connect

    Katayama, Tetsuo; Togashi, Tadashi; Tono, Kensuke; Kameshima, Takashi; Inubushi, Yuichi; Sato, Takahiro; Hatsui, Takaki; Yabashi, Makina; Obara, Yuki; Misawa, Kazuhiko; Bhattacharya, Atanu; Kurahashi, Naoya; Ogi, Yoshihiro; Suzuki, Toshinori

    2013-09-23

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

  4. The Interrelation of Soft and Hard X-Ray Emission During Solar Flares

    NASA Technical Reports Server (NTRS)

    Fisher, George H.

    1998-01-01

    The objective of this project is to determine the characteristics of flare energy transport processes through the study of soft X-rays, hard X-rays, and their interrelationships through analysis of Yohkoh SXT (Soft X-ray Telescope), HXT (Hard X- Ray Telescope) , and BCS (Bragg Crystal Spectrometer) data, and comparison with theoretical models.

  5. Hard x ray imaging graphics development and literature search

    NASA Technical Reports Server (NTRS)

    Emslie, A. Gordon

    1991-01-01

    This report presents work performed between June 1990 and June 1991 and has the following objectives: (1) a comprehensive literature search of imaging technology and coded aperture imaging as well as relevant topics relating to solar flares; (2) an analysis of random number generators; and (3) programming simulation models of hard x ray telescopes. All programs are compatible with NASA/MSFC Space Science LAboratory VAX Cluster and are written in VAX FORTRAN and VAX IDL (Interactive Data Language).

  6. Bulk sensitive hard x-ray photoemission electron microscopy

    SciTech Connect

    Patt, M. Wiemann, C.; Weber, N.; Escher, M.; Merkel, M.; Gloskovskii, A.; Drube, W.; Schneider, C. M.

    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.

  7. X-ray ablation of hyaluronan hydrogels: Fabrication of three-dimensional microchannel networks

    NASA Astrophysics Data System (ADS)

    Weon, B. M.; Chang, S.; Yeom, J.; Hahn, S. K.; Je, J. H.; Hwu, Y.; Margaritondo, G.

    2009-09-01

    We present a simple and highly versatile protocol for polymer ablation: hard x-ray irradiation makes it possible to rapidly depolymerize hyaluronan hydrogels and fabricate three-dimensional network of microchannels. Photodynamic and photochemical analyses show that x-ray irradiation directly cleaves the polymer backbone and the total dose controls the degradation kinetics. This nonthermal ablation protocol may offer opportunities for processing organic polymers and biological materials.

  8. THE SWIFT/BAT HARD X-RAY TRANSIENT MONITOR

    SciTech Connect

    Krimm, H. A.; Holland, S. T.; Corbet, R. H. D.; Pearlman, A. B.; Baumgartner, W. H.; Cummings, J. R.; Romano, P.; Kennea, J. A.; Bloom, J. S.; Barthelmy, S. D.; Gehrels, N.; Lien, A. Y.; Markwardt, C. B.; Ukwatta, T. N.; Palmer, D. M.; Sakamoto, T.; Stamatikos, M.

    2013-11-01

    The Swift/Burst Alert Telescope (BAT) hard X-ray transient monitor provides near real-time coverage of the X-ray sky in the energy range 15-50 keV. The BAT observes 88% of the sky each day with a detection sensitivity of 5.3 mCrab for a full-day observation and a time resolution as fine as 64 s. The three main purposes of the monitor are (1) the discovery of new transient X-ray sources, (2) the detection of outbursts or other changes in the flux of known X-ray sources, and (3) the generation of light curves of more than 900 sources spanning over eight years. The primary interface for the BAT transient monitor is a public Web site. Between 2005 February 12 and 2013 April 30, 245 sources have been detected in the monitor, 146 of them persistent and 99 detected only in outburst. Among these sources, 17 were previously unknown and were discovered in the transient monitor. In this paper, we discuss the methodology and the data processing and filtering for the BAT transient monitor and review its sensitivity and exposure. We provide a summary of the source detections and classify them according to the variability of their light curves. Finally, we review all new BAT monitor discoveries. For the new sources that are previously unpublished, we present basic data analysis and interpretations.

  9. The hard x-ray imager onboard IXO

    NASA Astrophysics Data System (ADS)

    Nakazawa, Kazuhiro; Takahashi, Tadayuki; Limousin, Olivier; Kokubun, Motohide; Watanabe, Shin; Laurent, Philippe; Arnaud, Monique; Tajima, Hiroyasu

    2010-07-01

    The Hard X-ray Imager (HXI) is one of the instruments onboard International X-ray Observatory (IXO), to be launched into orbit in 2020s. It covers the energy band of 10-40 keV, providing imaging-spectroscopy with a field of view of 8 x 8 arcmin2. The HXI is attached beneath the Wide Field Imager (WFI) covering 0.1-15 keV. Combined with the super-mirror coating on the mirror assembly, this configuration provides observation of X-ray source in wide energy band (0.1-40.0 keV) simultaneously, which is especially important for varying sources. The HXI sensor part consists of the semiconductor imaging spectrometer, using Si in the medium energy detector and CdTe in the high energy detector as its material, and an active shield covering its back to reduce background in orbit. The HXI technology is based on those of the Japanese-lead new generation X-ray observatory ASTRO-H, and partly from those developed for Simbol-X. Therefore, the technological development is in good progress. In the IXO mission, HXI will provide a major assets to identify the nature of the object by penetrating into thick absorbing materials and determined the inherent spectral shape in the energy band well above the structure around Fe-K lines and edges.

  10. The Swift/BAT Hard X-ray Transient Monitor

    NASA Technical Reports Server (NTRS)

    Krimm, H. A.; Holland, S. T.; Corbet, R.H.D.; Pearlman, A. B.; Romano, P.; Kennea, J. A.; Bloom, J. S.; Barthelmy, S. D.; Baumgartner, W. H.; Cummings, J. R.; Gehrels, N.; Lien, A. Y.; Markwardt, C. B.; Palmer, D. M.; Sakamoto, T.; Stamatikos, M.; Ukwatta, N.

    2013-01-01

    The Swift/Burst Alert Telescope (BAT) hard X-ray transient monitor provides near real-time coverage of the X-ray sky in the energy range 15-50 keV. The BAT observes 88% of the sky each day with a detection sensitivity of 5.3 mCrab for a full-day observation and a time resolution as ne as 64 seconds. The three main purposes of the monitor are (1) the discovery of new transient X-ray sources, (2) the detection of outbursts or other changes in the ux of known X-ray sources, and (3) the generation of light curves of more than 900 sources spanning over eight years. The primary interface for the BAT transient monitor is a public web page. Since 2005 February, 242 sources have been detected in the monitor, 149 of them persistent and 93 detected only in outburst. Among these sources, 16 were previously unknown and discovered in the transient monitor. In this paper, we discuss the methodology and the data processing and ltering for the BAT transient monitor and review its sensitivity and exposure. We provide a summary of the source detections and classify them according to the variability of their light curves. Finally, we review all new BAT monitor discoveries and present basic data analysis and interpretations for those sources with previously unpublished results.

  11. The Swift-BAT Hard X-Ray Transient Monitor

    NASA Technical Reports Server (NTRS)

    Krimm, H. A.; Holland, S. T.; Corbet, R. H. D.; Pearlman, A. B.; Romano, P.; Kennea, J. A.; Bloom, J. S.; Barthelmy, S. D.; Baumgartner, W. H.; Cummings, J. R.; Gehrels, N.; Lien, A. Y.; Markwardt, C. B.; Palmer, D. M.; Sakamoto, T.; Stamatikos, M.; Ukwatta, T. N.

    2013-01-01

    The Swift/Burst Alert Telescope (BAT) hard X-ray transient monitor provides near real-time coverage of the X-ray sky in the energy range 15-50 keV. The BAT observes 88% of the sky each day with a detection sensitivity of 5.3 mCrab for a full-day observation and a time resolution as fine as 64 s. The three main purposes of the monitor are (1) the discovery of new transient X-ray sources, (2) the detection of outbursts or other changes in the flux of known X-ray sources, and (3) the generation of light curves of more than 900 sources spanning over eight years. The primary interface for the BAT transient monitor is a public Web site. Between 2005 February 12 and 2013 April 30, 245 sources have been detected in the monitor, 146 of them persistent and 99 detected only in outburst. Among these sources, 17 were previously unknown and were discovered in the transient monitor. In this paper, we discuss the methodology and the data processing and filtering for the BAT transient monitor and review its sensitivity and exposure.We provide a summary of the source detections and classify them according to the variability of their light curves. Finally, we review all new BAT monitor discoveries. For the new sources that are previously unpublished, we present basic data analysis and interpretations.

  12. X-ray microscopy of soft and hard human tissues

    NASA Astrophysics Data System (ADS)

    Müller, Bert; Schulz, Georg; Deyhle, Hans; Stalder, Anja K.; Ilgenstein, Bernd; Holme, Margaret N.; Weitkamp, Timm; Beckmann, Felix; Hieber, Simone E.

    2016-01-01

    The simultaneous post mortem visualization of soft and hard tissues using absorption-based CT remains a challenge. If the photon energy is optimized for the visualization of hard tissue, the surrounding soft tissue components are almost X-ray transparent. Therefore, the combination with other modalities such as phase-contrast CT, magnetic resonance microscopy, and histology is essential to detect the anatomical features. The combination of the 2D and 3D data sets using sophisticated segmentation and registration tools allows for conclusions about otherwise inaccessible anatomical features essential for improved patient treatments.

  13. The need for hard X-ray imaging observations at the next solar maximum

    NASA Technical Reports Server (NTRS)

    Emslie, A. Gordon

    1988-01-01

    Canonical models of solar hard X-ray bursts; associated length and time scales; the adequacies and inadequacies of previous observations; theoretical modeling predictions; arcsecond imaging of solar hard X-rays are outlined.

  14. X-ray Properties of an Unbiased Hard X-ray Detected Sample of AGN

    NASA Technical Reports Server (NTRS)

    Winter, Lisa M.; Mushotzky, Richard F.; Tueller, Jack; Markwardt, Craig

    2007-01-01

    The SWIFT gamma ray observatory's Burst Alert Telescope (BAT) has detected a sample of active galactic nuclei (AGN) based solely on their hard X-ray flux (14-195keV). In this paper, we present for the first time XMM-Newton X-ray spectra for 22 BAT AGXs with no previously analyzed X-ray spectra. If our sources are a representative sample of the BAT AGN, as we claim, our results present for the first time global X-ray properties of an unbiased towards absorption (n(sub H) < 3 x 10(exp 25)/sq cm), local (< z >= 0.03), AGN sample. We find 9/22 low absorption (n(sub H) < 10(exp 23)/sq cm), simple power law model sources, where 4 of these sources have a statistically significant soft component. Among these sources, we find the presence of a warm absorber statistically significant for only one Seyfert 1 source, contrasting with the ASCA results of Reynolds (1997) and George et al. (1998), who find signatures of warm absorption in half or more of their Seyfert 1 samples at similar redshifts. Additionally, the remaining sources (13122) have more complex spectra, well-fit by an absorbed power law at E > 2.0 keV. Five of the complex sources (NGC 612, ESO 362-G018, MRK 417, ESO 506-G027, and NGC 6860) are classified as Compton-thick candidates. Further, we find four more sources (SWIFT J0641.3+3257, SWIFT J0911.2+4533, SWIFT J1200.8+0650, and NGC 4992) with properties consistent with the hidden/buried AGN reported by Ueda et al. (2007). Finally, we include a comparison of the XMM EPIC spectra with available SWIFT X-ray Telescope (XRT) observations. From these comparisons, we find 6/16 sources with varying column densities, 6/16 sources with varying power law indices, and 13/16 sources with varying fluxes, over periods of hours to months. Flux and power law index are correlated for objects where both parameters vary.

  15. Short focal length Kirkpatrick-Baez mirrors for a hard x-ray nanoprobe

    SciTech Connect

    Liu Wenjun; Ice, Gene E.; Tischler, Jonathan Z.; Khounsary, Ali; Liu, Chian; Assoufid, Lahsen; Macrander, Albert T.

    2005-11-15

    We describe progress in the fabrication of short-focal-length total-external-reflection Kirkpatrick-Baez x-ray mirrors with ultralow figure errors. The short focal length optics produce nanoscale beams (<100 nm) on conventional ({approx}64 m long) beamlines at third generation synchrotron sources. The total-external reflection optics are inherently achromatic and efficiently focus a white (polychromatic) or a tunable monochromatic spectrum of x rays. The ability to focus independent of wavelength allows novel new experimental capabilities. Mirrors have been fabricated both by computer assisted profiling (differential polishing) and by profile coating (coating through a mask onto ultra-smooth surfaces). A doubly focused 85x95 nm{sup 2} hard x-ray nanobeam has been obtained on the UNICAT beamline 34-ID at the Advanced Photon Source. The performance of the mirrors, techniques for characterizing the spot size, and factors limiting focusing performance are discussed.

  16. Short Focal Length Kirkpatrick-Baez Mirrors for a Hard X-Ray Nanoprobe

    SciTech Connect

    Liu, Wenjun; Ice, Gene E; Tischler, Jonathan Zachary; Khounsary, Ali; Liu, Chian; Assoufid, Lahsen; Macrander, Albert T.

    2005-01-01

    We describe progress in the fabrication of short-focal-length total-external-reflection Kirkpatrick-Baez x-ray mirrors with ultralow figure errors. The short focal length optics produce nanoscale beams (<100 nm) on conventional ({approx} 64 m long) beamlines at third generation synchrotron sources. The total-external reflection optics are inherently achromatic and efficiently focus a white (polychromatic) or a tunable monochromatic spectrum of x rays. The ability to focus independent of wavelength allows novel new experimental capabilities. Mirrors have been fabricated both by computer assisted profiling (differential polishing) and by profile coating (coating through a mask onto ultra-smooth surfaces). A doubly focused 85 x 95 nm{sup 2} hard x-ray nanobeam has been obtained on the UNICAT beamline 34-ID at the Advanced Photon Source. The performance of the mirrors, techniques for characterizing the spot size, and factors limiting focusing performance are discussed.

  17. Discovery of hard X-ray outbursts from the soft X-ray transient Aquila X-1.

    NASA Astrophysics Data System (ADS)

    Harmon, B. A.; Wilson, C. A.; Tavani, M.; Zhang, S. N.; Rubin, B. C.; Paciesas, W. S.; Ford, E. C.; Kaaret, P.

    1996-11-01

    We report the BATSE discovery of hard X-ray outbursts from the soft X-ray transient Aquila X-1 (Aql X-1). Aql X-1 is the most prolific of the soft X-ray transient sources and it has been known to produce large outbursts near the Eddington limit in the 1-10keV energy band. The typical recurrence time of outbursts is about 1-year. Aql X-1 shows type I X-ray bursts during the decay phase of the X-ray outbursts and is believed to contain a neutron star. These characteristics of Aql X-1 make it an ideal system to study time variable hard X-ray emission from accreting neutron stars. BATSE has monitored Aql X-1 continuously since the Compton Observatory mission began in April 1991. Several episodes of hard X-ray emission with durations of weeks to months have been detected in 1991-1994. These episodes are coincident with substantial brightening of the optical counterpart and to a lesser degree with observations of soft X-ray emission by ROSAT, EURECA/WATCH and ASCA. We find fluxes in the 20-100mCrab range with hard spectra extending to above 100keV and power law spectral fits yielding photon indices between -2 and -3.

  18. The Swift/BAT Hard X-ray Survey

    NASA Technical Reports Server (NTRS)

    Tueller, Jack; Markwardt, C. B.; Mushotzky, R. F.; Barthelmy, S. D.; Gehrels, N.; Krimm, A.; Skinner, G. K.; Falcone, A.; Kennea, J. A.

    2006-01-01

    The BAT instrument on Swift is a wide field (70 deg. '100 deg.) coded aperture instrument with a CdZnTe detector array sensitive to energies of 14-200 keV. Each day, the BAT survey typically covers 60% of the sky to a detection limit of 30 millicrab. BAT makes hard X-ray light curves of similar sensitivity and coverage to the X-ray light curves from XTE/ASM, but in an energy range where sources show remarkably different behavior. Integrating the BAT data produces an all sky map with a source detection limit at 15 months of a few 10(exp -11) ergs per square centimeter per second, depending on the exposure. This is the first uniform all-sky survey at energies high enough to be unaffected by absorption since HEAO 1 in 1977-8. BAT has detected greater than 200 AGN and greater than 180 galactic sources. At high galactic latitudes, the BAT sources are usually easy to identify, but many are heavily absorbed and there are a few quite surprising identifications. The BAT selected galaxies can be used to calculate LogN/LogS and the luminosity function for AGN which are complete and free from common systematics. Several crucial parameters for understanding the cosmic hard x-ray background are now determined.

  19. Hard X-ray spectrum of Cygnus X-1

    NASA Technical Reports Server (NTRS)

    Nolan, P. L.; Gruber, D. E.; Knight, F. K.; Matteson, J. L.; Rothschild, R. E.; Marshall, F. E.; Levine, A. M.; Primini, F. A.

    1981-01-01

    Long-term measurements of the hard X-ray spectrum from 3 keV to 8 MeV of the black-hole candidate Cygnus X-1 in its low state are reported. Observations were made from October 26 to November 18, 1977 with the A2 (Cosmic X-ray) and A4 (Hard X-ray and Low-Energy Gamma-Ray) experiments on board HEAO 1 in the spacecraft's scanning mode. The measured spectrum below 200 keV is found to agree well with previous spectra which have been fit by a model of the Compton scattering of optical or UV photons in a very hot plasma of electron temperature 32.4 keV and optical depth 3.9 or 1.6 for spherical or disk geometry, respectively. At energies above 300 keV, however, flux excess is observed which may be accounted for by a distribution of electron temperatures from 15 to about 100 keV.

  20. Hard X-rays from hybrid X pinches

    SciTech Connect

    Shelkovenko, T. A. Pikuz, S. A.; Hoyt, C. L.; Cahill, A. D.; Hammer, D. A.; Tilikin, I. N.; Mingaleev, A. R.; Agafonov, A. V.

    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.

  1. Beyond sunshine: Hard x-rays for precision microfabrication

    SciTech Connect

    Johnson, Erik D.; Siddons, D. Peter; Milne, J. Christopher; Gueckel, Henry; Klein, Jonathan L.

    1997-07-01

    For several years we have explored the use of hard x-rays for a broad range of lithographic applications. The high energy available from the NSLS x-ray ring (E>15 keV) allows the exposure of resist up to several cm thick, while maintaining micron level precision. The high flux and close proximity to the source at this machine make it possible to achieve workable exposures on realistic time scales, enabling production work. In addition to the conventional two-dimensional exposure schemes, we have demonstrated methods for achieving fully figured three dimensional objects with internal re-entrant geometry. Users from outside BNL have been sufficiently successful with their work at our prototype beamline (X-27B) that we have initiated the construction of a dedicated exposure station (X-14B) for High Aspect Ratio Precision Manufacture. An overview of our previous work as well as the current status of the new beamline will be described.

  2. Hard x-ray scanning microscopy with coherent radiation: Beyond the resolution of conventional x-ray microscopes

    SciTech Connect

    Schropp, A.; Hoppe, R.; Patommel, J.; Samberg, D.; Seiboth, F.; Stephan, S.; Schroer, C. G.; Wellenreuther, G.; Falkenberg, G.

    2012-06-18

    We demonstrate x-ray scanning coherent diffraction microscopy (ptychography) with 10 nm spatial resolution, clearly exceeding the resolution limits of conventional hard x-ray microscopy. The spatial resolution in a ptychogram is shown to depend on the shape (structure factor) of a feature and can vary for different features in the object. In addition, the resolution and contrast are shown to increase with increasing coherent fluence. For an optimal ptychographic x-ray microscope, this implies a source with highest possible brilliance and an x-ray optic with a large numerical aperture to generate the optimal probe beam.

  3. Deducing Electron Properties from Hard X-Ray Observations

    NASA Technical Reports Server (NTRS)

    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.; Piana, M.; Prato, M.; Schmahl, E. J.; Suarez-Garcia, E.

    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.

  4. Deducing Electron Properties from Hard X-ray Observations

    NASA Astrophysics Data System (ADS)

    Kontar, E. P.; Brown, J. C.; Emslie, A. G.; Hajdas, W.; Holman, G. D.; Hurford, G. J.; Kašparová, J.; Mallik, P. C. V.; Massone, A. M.; McConnell, M. L.; Piana, M.; Prato, M.; Schmahl, E. J.; Suarez-Garcia, E.

    2011-09-01

    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.

  5. Virtual Young's Double Slit Experiment for Hard X-ray Photons

    NASA Astrophysics Data System (ADS)

    Isakovic, Abdel; Evans-Lutterodt, K.; Siddons, D. P.; Stein, A.; Warren, J. B.; Sandy, A.; Narayanan, S.; Metzler, M.

    2010-03-01

    Coherent hard X-ray beams underlie many of the recent advances in X-ray imaging and characterization, and it is crucial to quantify the coherence properties of X-ray beams for further advances. The classic Young's double slit experiment is an accepted method from which one can deduce the transverse coherence length, but unfortunately the double slit experiment is difficult to implement at these wavelengths. Micro-fabricated prisms are used to implement a virtual Young's double slit experiment, and interference fringes are quantified by X-ray fluorescence from a 30 nm Cr film in addition to being recorded with YAG crystal and CCD. The maximum number of fringes in the classical overlap region is comparable to δ/4πβ, the ratio of real to imaginary parts of the X-ray refractive index of the prism material. We have measured the horizontal and vertical transverse coherence lengths at beamline APS 8-ID. We suggest this to be a flexible, easily applied method that can be implemented at X-ray laboratories for both, coherence measurements and interferometric imaging. http://arxiv.org/abs/0910.5524

  6. The impulsive hard X-rays from solar flares

    NASA Technical Reports Server (NTRS)

    Leach, J.

    1984-01-01

    A technique for determining the physical arrangement of a solar flare during the impulsive phase was developed based upon a nonthermal model interpretation of the emitted hard X-rays. Accurate values are obtained for the flare parameters, including those which describe the magnetic field structure and the beaming of the energetic electrons, parameters which have hitherto been mostly inaccessible. The X-ray intensity height structure can be described readily with a single expression based upon a semi-empirical fit to the results from many models. Results show that the degree of linear polarization of the X-rays from a flaring loop does not exceed 25 percent and can easily and naturally be as low as the polarization expected from a thermal model. This is a highly significant result in that it supersedes those based upon less thorough calculations of the electron beam dynamics and requires that a reevaluation of hopes of using polarization measurements to discriminate between categories of flare models.

  7. Hard-X-Ray-Induced Multistep Ultrafast Dissociation

    NASA Astrophysics Data System (ADS)

    Travnikova, Oksana; Marchenko, Tatiana; Goldsztejn, Gildas; Jänkälä, Kari; Sisourat, Nicolas; Carniato, Stéphane; Guillemin, Renaud; Journel, Loïc; Céolin, Denis; Püttner, Ralph; Iwayama, Hiroshi; Shigemasa, Eiji; Piancastelli, Maria Novella; Simon, Marc

    2016-05-01

    Creation of deep core holes with very short (τ ≤1 fs ) lifetimes triggers a chain of relaxation events leading to extensive nuclear dynamics on a few-femtosecond time scale. Here we demonstrate a general multistep ultrafast dissociation on an example of HCl following Cl 1 s →σ* excitation. Intermediate states with one or multiple holes in the shallower core electron shells are generated in the course of the decay cascades. The repulsive character and large gradients of the potential energy surfaces of these intermediates enable ultrafast fragmentation after the absorption of a hard x-ray photon.

  8. Hard-X-Ray-Induced Multistep Ultrafast Dissociation.

    PubMed

    Travnikova, Oksana; Marchenko, Tatiana; Goldsztejn, Gildas; Jänkälä, Kari; Sisourat, Nicolas; Carniato, Stéphane; Guillemin, Renaud; Journel, Loïc; Céolin, Denis; Püttner, Ralph; Iwayama, Hiroshi; Shigemasa, Eiji; Piancastelli, Maria Novella; Simon, Marc

    2016-05-27

    Creation of deep core holes with very short (τ≤1  fs) lifetimes triggers a chain of relaxation events leading to extensive nuclear dynamics on a few-femtosecond time scale. Here we demonstrate a general multistep ultrafast dissociation on an example of HCl following Cl 1s→σ^{*} excitation. Intermediate states with one or multiple holes in the shallower core electron shells are generated in the course of the decay cascades. The repulsive character and large gradients of the potential energy surfaces of these intermediates enable ultrafast fragmentation after the absorption of a hard x-ray photon. PMID:27284654

  9. Probing deeper by hard x-ray photoelectron spectroscopy

    SciTech Connect

    Risterucci, P.; Renault, O. Martinez, E.; Delaye, V.; Detlefs, B.; Zegenhagen, J.; Gaumer, C.; Grenet, G.; Tougaard, S.

    2014-02-03

    We report an hard x-ray photoelectron spectroscopy method combining high excitation energy (15 keV) and improved modelling of the core-level energy loss features. It provides depth distribution of deeply buried layers with very high sensitivity. We show that a conventional approach relying on intensities of the core-level peaks is unreliable due to intense plasmon losses. We reliably determine the depth distribution of 1 ML La in a high-κ/metal gate stack capped with 50 nm a-Si. The method extends the sensitivity of photoelectron spectroscopy to depths beyond 50 nm.

  10. Interferometric hard x-ray phase contrast imaging at 204 nm grating period

    SciTech Connect

    Wen Han; Gomella, Andrew A.; Miao, Houxun; Lynch, Susanna K.; Wolfe, Douglas E.; Xiao Xianghui; Liu Chian; Morgan, Nicole

    2013-01-15

    We report on hard x-ray phase contrast imaging experiments using a grating interferometer of approximately 1/10th the grating period achieved in previous studies. We designed the gratings as a staircase array of multilayer stacks which are fabricated in a single thin film deposition process. We performed the experiments at 19 keV x-ray energy and 0.8 {mu}m pixel resolution. The small grating period resulted in clear separation of different diffraction orders and multiple images on the detector. A slitted beam was used to remove overlap of the images from the different diffraction orders. The phase contrast images showed detailed features as small as 10 {mu}m, and demonstrated the feasibility of high resolution x-ray phase contrast imaging with nanometer scale gratings.

  11. HARD X-RAY EMISSION FROM THE NGC 5044 GROUP

    SciTech Connect

    Henriksen, Mark J.

    2011-01-01

    Observations made with the Rossi X-ray Timing Explorer Proportional Counter Array (PCA) to constrain the hard X-ray emission in the NGC 5044 group are reported here. Modeling a combined PCA and ROSAT position sensitive proportional counter spectrum with a 0.5-15 keV energy range shows excess hard emission above 4 keV. Addition of a power-law component with a spectral index of 2.6-2.8 and a luminosity of 2.6 x 10{sup 42} erg s{sup -1} within 700 kpc in the observed energy band removes these residuals. Thus, there is a detection of a significant non-thermal component that is 32% of the total X-ray emission. Point-source emission makes up at most 14% of the non-thermal emission from the NGC 5044 group. Therefore, the diffuse, point-source-subtracted, non-thermal component is (2.2-3.0) x 10{sup 42} erg s{sup -1}. The cosmic-ray electron energy density is 3.6 x 10{sup -12} erg cm{sup -3} and the average magnetic field is 0.034 {mu}G in the largest radio emitting region. The ratio of cosmic-ray electron energy density to magnetic field energy density, {approx}2.5 x 10{sup 4}, is significantly out of equipartition and is therefore atypical of radio lobes. In addition, the group's small size and low non-thermal energy density strongly contradicts the size-energy relationship found for radio lobes. Thus, it is unlikely related to the active galaxy and is most likely a relic of the merger. The energy in cosmic rays and magnetic field is consistent with simulations of cosmic-ray acceleration by merger shocks.

  12. White-light flares, Hard X-Rays, and Heights

    NASA Astrophysics Data System (ADS)

    Martinez Oliveros, Juan Carlos; Hudson, Hugh S.; Krucker, Sam

    2016-05-01

    The white-light continuum of a solar flare was the first manifestation of a solar flare ever detected. Nevertheless, its mechanisms remain unknown, even today. Improved observations confirm the identification of white-light continuum emission and hard X-rays during the impulsive phase of a solar flare, both in space and in time, to within the observational limits. Two events observed near the limb, but not occulted by it (SOL2011-02-24 and SOL2012-02-18), show that these emissions appear to have physical heights lower than predicted by models by hundreds of kms, referring height to the location of optical-depth unity at disk center in the 500 nm continuum. We describe these results and place them in the context of the three extreme-limb events (within about 1o) reported by Krucker et al. (2015). The electrons responsible for hard X-ray bremsstrahlung coincide with the most intense flare energy release, but we do not presently understand the physics of energy transport nor the nature of particle acceleration apparently taking place at heights below the preflare temperature minimum.

  13. Discovery in Cygnus X-3 of correlated behavior between the hard X-ray and radio

    NASA Technical Reports Server (NTRS)

    McCollough, M. L.; Harmon, B. A.; Robinson, C. R.; Zhang, S. N.; Hjellming, R. M.; Waltman, E. B.; Ghigo, F. D.; Foster, R. S.; Johnston, K. J.

    1997-01-01

    Using the Compton Gamma Ray Observatory (CGRO)/burst and transient search experiment (BATSE) hard X-ray data together with GHz radio monitoring data, a long term study was performed on the unusual X-ray binary Cyg X-3. This study resulted in the discovery of a relationship between the two wavebands. The combined data show that the radio emission is linked to the hard X-ray production. Radio flares, preflare low radio states and quiescence radio emission can be associated with changes in the hard X-ray intensity. Jet production is directly related to changes in the hard X-ray emission.

  14. Disentangling the Hard X-ray Background ROSAT HRI

    NASA Technical Reports Server (NTRS)

    Murray, Stephen S.

    1999-01-01

    The goal of our investigation was to improve our understanding of the properties of the discrete X-ray sources that produce the X-ray background (XRB). Many surveys have shown that the XRB at energies of 0.5-3.0 keV is dominated by emission from extragalactic point sources and that a significant fraction of the XRB at higher energies also is produced by discrete sources. In spite of the fact that the bulk of the 0.5-10 keV XRB was demonstrated to arise from extragalactic point sources, the spectral shape of the background presented a difficulty, referred to as the "spectral paradox". Spectra for classes of individual sources generally have been found to be incompatible with the observed energy index, alpha = 0.4 of the XRB over the 2-10 keV energy range. For the 0.3-3.0 keV Einstein band, Macca'caro et al. (1988) derived a mean energy spectral index of a approx. 0.95 for 599 extragalactic sources and for a subset of X-ray selected AGN, found alpha = 1.03(sup +0-05, sub -0.06) . Wilkes and Elvis showed that radio "loudness" was strongly correlated with the source spectrum, such that radio-load quasars exhibited flatter spectra (alpha approx. 0.5), while radio-quiet quasars had steeper spectra (alpha approx. 1). Studies of moderately faint sources in the 0.1-2.0 keV ROSAT band also found rather steep spectra (alpha = 0.96 +/- 0.11 for sources with an average flux of 1.5 x 10(exp -14) ergs/sq cm sec). At higher energies and much higher fluxes, energy spectra of individual AGN suggested a "canonical" alpha = 0.7 energy spectrum. Thus, the best evidence suggested that known classes of AGN could not readily explain the observed X-ray background spectrum. In our ROSAT PSPC analysis, we studied not only the traditional log N - log S, but also the spectral properties of the sources. We computed hardness ratios for individual sources and performed spectral fits to the summed source spectra, averaged in flux bins from 10(exp -15) to 10(exp -12) ergs/sq cm sec. We found that

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

    PubMed

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

    2014-11-01

    We report the development of a laboratory-based Rowland-circle monochromator that incorporates a low power x-ray (bremsstrahlung) tube source, a spherically bent crystal analyzer, and an energy-resolving solid-state detector. This relatively inexpensive, introductory level instrument achieves 1-eV energy resolution for photon energies of ∼5 keV to ∼10 keV while also demonstrating a net efficiency previously seen only in laboratory monochromators having much coarser energy resolution. Despite the use of only a compact, air-cooled 10 W x-ray tube, we find count rates for nonresonant x-ray emission spectroscopy comparable to those achieved at monochromatized spectroscopy beamlines at synchrotron light sources. For x-ray absorption near edge structure, the monochromatized flux is small (due to the use of a low-powered x-ray generator) but still useful for routine transmission-mode studies of concentrated samples. These results indicate that upgrading to a standard commercial high-power line-focused x-ray tube or rotating anode x-ray generator would result in monochromatized fluxes of order 10(6)-10(7) photons/s with no loss in energy resolution. This work establishes core technical capabilities for a rejuvenation of laboratory-based hard x-ray spectroscopies that could have special relevance for contemporary research on catalytic or electrical energy storage systems using transition-metal, lanthanide, or noble-metal active species. PMID:25430123

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

    SciTech Connect

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

    2014-11-15

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

  17. Fabrication of composite x-ray masks by micromilling

    NASA Astrophysics Data System (ADS)

    Coane, Philip J.; Friedrich, Craig R.

    1996-09-01

    An important aspect for the development of micromanufactured components and systems is to reduce the time and cost required to reach the prototype stage. At present, this development typically spans several years. Any fabrication approach which would reduce the cost and time-to-prototype would allow for the more rapid development of design concepts and the more rapid evolution of the design cycle. Direct fabrication of masks for X-ray lithography, by mechanical micromilling, is one potential avenue for rapid, lower cost development. The key process requirements for the fabrication of a typical X-ray mask involves the selection of both substrate and absorber materials. The substrate must provide a mechanically stable support for the patterned absorber without introducing excessive attenuation of the X- ray flux that ultimately reaches the resist surface. Frame supported, thin membranes (such as SiC, C, Si3N4, Si) are most often used as well as low atomic number bulk materials (Be). The choice of elemental composition and thickness for the absorber will be largely determined by the resist sensitivity and the X-ray wavelength used. Many process steps are required in order to define the final absorber pattern geometry and will generally involve either additive or subtractive processes. Mechanical micromilling techniques may be used with either a single bulk material which serves the dual role of both substrate and absorber or with a composite structure consisting of a thin gold layer deposited on a thick, low atomic number bulk substrate. Single material masks of aluminum and graphite have been investigated. A composite mask of graphite with a thin layer of sputtered gold has also been investigated. The paper will report on the developmental work for both types of masks and will give results for synchrotron X-ray exposure using these masks. Problems associated with using micromilling as an X- ray mask fabrication method will also be presented.

  18. High-Energy X-Ray Timing Experiment Detections of Hard X-Ray Tails in Scorpius X-1

    NASA Astrophysics Data System (ADS)

    D'Amico, Flavio; Heindl, William A.; Rothschild, Richard E.; Gruber, Duane E.

    2001-02-01

    We report the detection of a nonthermal hard X-ray component from Sco X-1 based on the analysis of 20-220 keV spectra obtained with the High-Energy X-Ray Timing Experiment on board the Rossi X-Ray Timing Explorer satellite. We find that the addition of a power-law component to a thermal bremsstrahlung model is required to achieve a good fit in five of 16 observations analyzed. Using Proportional Counter Array data, we were able to track the movement of the source along the Z diagram, and we found that the presence of the hard X-ray tail is not confined to a specific Z position. However, we do observe an indication that the power-law index hardens with increasing M, as indicated from the position on the Z diagram. We find that the derived nonthermal luminosities are ~10% of that derived for the brightest of the atoll sources.

  19. Evidence for beamed electrons in a limb X-ray flare observed by Hard X-Ray Imaging Spectrometer (HXIS)

    NASA Technical Reports Server (NTRS)

    Haug, Eberhard; Elwert, Gerhard

    1986-01-01

    The limb flare of November 18, 1980, 14:51 UT, was investigated on the basis of X-ray images taken by the Hard X-ray Imaging Spectrometer (HXIS) and of X-ray spectra from the Hard X-Ray Burst Spectrometer (HXRBS) aboard the Solar Maximum Mission (SMM). The impulsive burst was also recorded at microwave frequencies between 2 and 20 GHz whereas no optical flare and no radio event at frequencies below 1 GHz were reported. The flare occurred directly at the SW limb of the solar disk. Taking advantage of the spatial resolution of HXIS images, the time evolution of the X-radiation originating from relatively small source regions can be studied. Using Monte Carlo computations of the energy distribution of energetic electrons traversing the solar plasma, the bremsstrahlung spectra produced by the electrons were derived.

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

    NASA Technical Reports Server (NTRS)

    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.

  1. Small pixel CZT detector for hard X-ray spectroscopy

    NASA Astrophysics Data System (ADS)

    Wilson, Matthew David; Cernik, Robert; Chen, Henry; Hansson, Conny; Iniewski, Kris; Jones, Lawrence L.; Seller, Paul; Veale, Matthew C.

    2011-10-01

    A new small pixel cadmium zinc telluride (CZT) detector has been developed for hard X-ray spectroscopy. The X-ray performance of four detectors is presented and the detectors are analysed in terms of the energy resolution of each pixel. The detectors were made from CZT crystals grown by the travelling heater method (THM) bonded to a 20×20 application specific integrated circuit (ASIC) and data acquisition (DAQ) system. The detectors had an array of 20×20 pixels on a 250 μm pitch, with each pixel gold-stud bonded to an energy resolving circuit in the ASIC. The DAQ system digitised the ASIC output with 14 bit resolution, performing offset corrections and data storage to disc in real time at up to 40,000 frames per second. The detector geometry and ASIC design was optimised for X-ray spectroscopy up to 150 keV and made use of the small pixel effect to preferentially measure the electron signal. A 241Am source was used to measure the spectroscopic performance and uniformity of the detectors. The average energy resolution (FWHM at 59.54 keV) of each pixel ranged from 1.09±0.46 to 1.50±0.57 keV across the four detectors. The detectors showed good spectral performance and uniform response over almost all pixels in the 20×20 array. A large area 80×80 pixel detector will be built that will utilise the scalable design of the ASIC and the large areas of monolithic spectroscopic grade THM grown CZT that are now available. The large area detector will have the same performance as that demonstrated here.

  2. Fabrication of X-ray telescopes for sounding rocket flights

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Two X-ray telescopes and two detector systems were fabricated, and one of the telescopes (15 in. diameter, Wolter type I telescope) was flown on two sounding rocket flights. The telescopes were fabricated using the diamond point technique which provided the accurate figure of the mirrors to about a focal plane blur of 0.5 arc minutes. The 15 in. telescope mirrors were polished using standard polishing techniques to remove tooling marks from the diamond turning, then chemically polished to bring the X-ray reflectivity up to nearly the theoretical values. The optical image formed by the 15 in. telescope was found to produce a blur of about 40 arc seconds for a parallel beam of incoming laser light. The first flight of the telescope produced an X-ray image of Capella which indicated that the X-ray image was blurred to the extent of about 2 arc minutes. This additional image degradation was due to a slight error in focusing the X-ray image onto the detector.

  3. Exploring hard X-ray polarimetry with Astrosat-CZTI

    NASA Astrophysics Data System (ADS)

    Vadawale, Santosh

    2016-07-01

    The CZT Imager instrument onboard recently launched Astrosat is a hard X-ray telescope capable of spectroscopy and imaging in the energy range of 20 - 150 keV using the technique of coded mask imaging. It consists of a large array of pixilated CZT detector modules as the detector plane having total geometric area of 976 cm^{2} and thickness of 5 mm. Since the detectors have significant detection efficiency beyond the primary energy range of CZTI, it can also be used for spectroscopy as well as polarization measurement in the extended energy range of 150 - 300 keV by identifying the Compton scattering events in the adjacent pixels. The polarimetric capability of Astrosat-CZTI using the Compton events has been investigated in detail by means of Geant4 simulations and has been experimentally demonstrated during the ground testing of CZTI. The pertinence of Compton events in the CZTI detector plane for astrophysical observation has demonstrated during the early observation with the detection of multiple GRBs in the Compton events. One GRB detected by CZTI show presence of azimuthal modulation suggesting highly polarized nature of the X-ray emission. The initial Crab observations also indicate presence of azimuthal modulation. Here we present preliminary analysis of the Compton events in the multiple observations carried out during the initial performance verification phase of Astrosat CZTI.

  4. Fabrication of an X-Ray Imaging Detector

    NASA Technical Reports Server (NTRS)

    Alcorn, G. E.; Burgess, A. S.

    1986-01-01

    X-ray detector array yields mosaic image of object emitting 1- to 30-keV range fabricated from n-doped silicon wafer. In proposed fabrication technique, thin walls of diffused n+ dopant divide wafer into pixels of rectangular cross section, each containing central electrode of thermally migrated p-type metal. This pnn+ arrangement reduces leakage current by preventing transistor action caused by pnp structure of earlier version.

  5. Hard X-Ray and Wide Focusing Telescopes

    NASA Technical Reports Server (NTRS)

    Gorenstein, Paul

    1998-01-01

    Studies are being carried out to compare the performance of several different separation materials used in the replication process. This report presents the results obtained during the second year of a program which consists of replicating smooth, thin substrates, depositing multilayer coatings upon them, and evaluating their performance. Replication and multilayer coatings are both critically important to the development of focussing hard X-ray telescopes that function up to 100 keV. The activities of the current year include extending the comparison between sputtered amorphous carbon and evaporated gold to include sputtered as well as evaporated gold. The figure of merit being the smoothness of the replica which has a direct effect on the specular reflectivity. These results were obtained with epoxy replication, but they should be applicable to electroformed nickel, the process we expect to use for the ultimate replicated optics.

  6. New HMI hard X-ray Diffraction Beamlines at BESSY

    SciTech Connect

    Denks, I. A.; Genzel, C.; Dudzik, E.; Feyerherm, R.; Klaus, M.; Wagener, G.

    2007-01-19

    Since April 2005 the Hahn-Meitner-Institute is operating two new beamlines for energy dispersive diffraction experiments (EDDI) and for (resonant) magnetic scattering (MAGS) at BESSY. The source for both beamlines is a superconducting 7 T multipole wiggler which provides hard X-ray photons with energies between 4 and 150 keV. The EDDI beamline uses the white beam and is intended for residual stress measurements on small samples as well as heavy engineering parts. The MAGS beamline delivers a focussed monochromatic beam with photon fluxes in the 1012 (s 100 mA 0.1 % bandwidth)-1 range at energies from 4 to 30 keV. It is equipped for single crystal diffraction and resonant (magnetic) scattering experiments as well as for the study of thin films, micro-, and nanostructures in materials science.

  7. New HMI hard X-ray Diffraction Beamlines at BESSY

    NASA Astrophysics Data System (ADS)

    Denks, I. A.; Genzel, C.; Dudzik, E.; Feyerherm, R.; Klaus, M.; Wagener, G.

    2007-01-01

    Since April 2005 the Hahn-Meitner-Institute is operating two new beamlines for energy dispersive diffraction experiments (EDDI) and for (resonant) magnetic scattering (MAGS) at BESSY. The source for both beamlines is a superconducting 7 T multipole wiggler which provides hard X-ray photons with energies between 4 and 150 keV. The EDDI beamline uses the white beam and is intended for residual stress measurements on small samples as well as heavy engineering parts. The MAGS beamline delivers a focussed monochromatic beam with photon fluxes in the 1012 (s 100 mA 0.1 % bandwidth)-1 range at energies from 4 to 30 keV. It is equipped for single crystal diffraction and resonant (magnetic) scattering experiments as well as for the study of thin films, micro-, and nanostructures in materials science.

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

    SciTech Connect

    Goo, Jawoong; Jeon, Soo Young; Oh, Tak Heon; Hong, Seung Phil; Lee, Won-Soo; Yon, Hwa Shik

    2007-01-19

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

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

    NASA Astrophysics Data System (ADS)

    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.

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

    NASA Technical Reports Server (NTRS)

    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.

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

    NASA Astrophysics Data System (ADS)

    Hong, JaeSub; Mori, Kaya; Hailey, Charles J.; Nynka, Melania; Zhang, Shuo; Gotthelf, Eric; Fornasini, Francesca M.; Krivonos, Roman; Bauer, Franz; Perez, Kerstin; Tomsick, John A.; Bodaghee, Arash; Chiu, Jeng-Lun; Clavel, Maïca; Stern, Daniel; Grindlay, Jonathan E.; Alexander, David M.; Aramaki, Tsuguo; Baganoff, Frederick K.; Barret, Didier; Barrière, Nicolas; Boggs, Steven E.; Canipe, Alicia M.; Christensen, Finn E.; Craig, William W.; Desai, Meera A.; Forster, Karl; Giommi, Paolo; Grefenstette, Brian W.; Harrison, Fiona A.; Hong, Dooran; Hornstrup, Allan; Kitaguchi, Takao; Koglin, Jason E.; Madsen, Kristen K.; Mao, Peter H.; Miyasaka, Hiromasa; Perri, Matteo; Pivovaroff, Michael J.; Puccetti, Simonetta; Rana, Vikram; Westergaard, Niels J.; Zhang, William W.; Zoglauer, Andreas

    2016-07-01

    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 deg{}2 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 clear Chandra counterparts for 58 NuSTAR sources and assign candidate counterparts for the remaining 19. The NuSTAR survey reaches X-ray luminosities of ˜4× and ˜8 × 10{}32 erg s{}-1 at the GC (8 kpc) in the 3–10 and 10–40 keV bands, respectively. The source list includes three 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 indicates that all the NuSTAR sources are in the central bulge or are of extragalactic origin. Spectral analysis of relatively bright NuSTAR sources suggests that magnetic cataclysmic variables constitute a large fraction (>40%–60%). Both spectral analysis and logN–logS distributions of the NuSTAR sources 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 Γ = 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 plasma temperatures than the field population.

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

    NASA Astrophysics Data System (ADS)

    Hong, JaeSub; Mori, Kaya; Hailey, Charles J.; Nynka, Melania; Zhang, Shuo; Gotthelf, Eric; Fornasini, Francesca M.; Krivonos, Roman; Bauer, Franz; Perez, Kerstin; Tomsick, John A.; Bodaghee, Arash; Chiu, Jeng-Lun; Clavel, Maïca; Stern, Daniel; Grindlay, Jonathan E.; Alexander, David M.; Aramaki, Tsuguo; Baganoff, Frederick K.; Barret, Didier; Barrière, Nicolas; Boggs, Steven E.; Canipe, Alicia M.; Christensen, Finn E.; Craig, William W.; Desai, Meera A.; Forster, Karl; Giommi, Paolo; Grefenstette, Brian W.; Harrison, Fiona A.; Hong, Dooran; Hornstrup, Allan; Kitaguchi, Takao; Koglin, Jason E.; Madsen, Kristen K.; Mao, Peter H.; Miyasaka, Hiromasa; Perri, Matteo; Pivovaroff, Michael J.; Puccetti, Simonetta; Rana, Vikram; Westergaard, Niels J.; Zhang, William W.; Zoglauer, Andreas

    2016-07-01

    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 deg{}2 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 clear Chandra counterparts for 58 NuSTAR sources and assign candidate counterparts for the remaining 19. The NuSTAR survey reaches X-ray luminosities of ∼4× and ∼8 × 10{}32 erg s{}-1 at the GC (8 kpc) in the 3–10 and 10–40 keV bands, respectively. The source list includes three 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 indicates that all the NuSTAR sources are in the central bulge or are of extragalactic origin. Spectral analysis of relatively bright NuSTAR sources suggests that magnetic cataclysmic variables constitute a large fraction (>40%–60%). Both spectral analysis and logN–logS distributions of the NuSTAR sources 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 Γ = 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 plasma temperatures than the field population.

  13. Direct fabrication of full-shell x-ray optics

    NASA Astrophysics Data System (ADS)

    Gubarev, M.; Ramsey, B.; Kolodziejczak, J. K.; Smith, W. S.; Roche, J.; Jones, W.; Griffith, C.; Kester, T.; Atkins, C.; Arnold, W.

    2015-09-01

    The next generation of astrophysical missions will require fabrication technology capable of producing high angular resolution x-ray mirrors. A full-shell direct fabrication approach using modern robotic polishing machines has the potential for producing stiff and light-weight shells that can be heavily nested, to produce large collecting areas, and are easier to mount, align and assemble, giving improved angular resolution. This approach to mirror fabrication, is being pursued at MSFC. The current status of this direct fabrication technology is presented.

  14. Fabrication of Compound Refractive X-ray Lenses Using LIGA Process and Performance Tests

    SciTech Connect

    Lee, Jin Pyoung; Kim, Guk Bae; Kim, Jong Hyun; Chang, Suk Sang; Lee, Sang Joon

    2007-01-19

    Recent advances of X-ray microscopy technology enable the visualization of some micro/nano-scale objects which optical microscopy and electron microscopy cannot be used to observe. The X-ray microscopy can be applied to observe the internal structure of a thicker sample than the electron microscopy can, and its spatial resolution is higher than that of the optical microscopy. Moreover, it has a powerful element specific imaging ability. For further improving the X-ray microscope, it is indispensable to make X-ray optics for focusing X-rays more effectively. Recently, various X-ray lenses such as diffraction lenses of FZP(Fresnel zone plate) and spatter-sliced FZT, total reflection lenses of K-B(Kirkpatrick-Baez) mirror and Wolter mirror, and refractive lens of CRL(compound refractive lens) were introduced. Compared with the other types of lenses, CRL is easy to fabricate and handle. In this study, we designed and fabricated various types of CRLs using LIGA(LIthographie, Galvanoformung, Abformtechnik) process, and used PMMA(Poly(methyl methacrylate)) material as the material of CRL. Their performances are tested with varying parameters such as parabolic/kinoform shape, radius of curvature, wall thickness between adjacent lenses, and width of lenses. The performance tests were carried out by using a simple synchrotron X-ray imaging method. The tests results revealed that hard x-rays could be condensed well by the CRL of PMMA material at the focal point we expect We captured sample images one-dimensionally magnified by CRLs. Furthermore, we found which parameter is more effective for enhancing focus efficiency and which parameter should be considered more carefully in the fabrication process of LIGA.

  15. Low dose hard x-ray contact microscopy assisted by a photoelectric conversion layer

    SciTech Connect

    Gomella, Andrew; Martin, Eric W.; Lynch, Susanna K.; Wen, Han; Morgan, Nicole Y.

    2013-04-15

    Hard x-ray contact microscopy provides images of dense samples at resolutions of tens of nanometers. However, the required beam intensity can only be delivered by synchrotron sources. We report on the use of a gold photoelectric conversion layer to lower the exposure dose by a factor of 40 to 50, allowing hard x-ray contact microscopy to be performed with a compact x-ray tube. We demonstrate the method in imaging the transmission pattern of a type of hard x-ray grating that cannot be fitted into conventional x-ray microscopes due to its size and shape. Generally the method is easy to implement and can record images of samples in the hard x-ray region over a large area in a single exposure, without some of the geometric constraints associated with x-ray microscopes based on zone-plate or other magnifying optics.

  16. Picosecond-resolved X-ray absorption spectroscopy at low signal contrast using a hard X-ray streak camera

    SciTech Connect

    Adams, Bernhard W.; Rose-Petruck, Christoph; Jiao, Yishuo

    2015-06-24

    A picosecond-resolving hard-X-ray streak camera has been in operation for several years at Sector 7 of the Advanced Photon Source (APS). Several upgrades have been implemented over the past few years to optimize integration into the beamline, reduce the timing jitter, and improve the signal-to-noise ratio. These include the development of X-ray optics for focusing the X-rays into the sample and the entrance slit of the streak camera, and measures to minimize the amount of laser light needed to generate the deflection-voltage ramp. For the latter, the photoconductive switch generating the deflection ramp was replaced with microwave power electronics. With these, the streak camera operates routinely at 88 MHz repetition rate, thus making it compatible with all of the APS fill patterns including use of all the X-rays in the 324-bunch mode. Sample data are shown to demonstrate the performance.

  17. Balloon observations of hard X-rays from some galactic X-ray sources

    NASA Technical Reports Server (NTRS)

    Damle, S. V.; Kunte, P. K.; Naranan, S.; Sreekantan, B. V.; Leahy, D. A.; Venkatesan, D.

    1985-01-01

    An X-ray telescope consisting of 400 cm phoswich detectors (NaI(T1)/CsI(Na)) was flown from Hyderabad (India) on 18 December 1984. The field of view was 5 deg x 5 deg FWHM. In a 10 hour float at 4 MB several galactic X-ray sources were tracked by the telescope using an on-board microprocessor. Fluxes and spectra in 18-120 keV X-rays for SCO X-1, GX 1+4, Gx 5-1, GX 17+2, SCT X-1, CYC X-1 an CYG X-3 will be presented.

  18. THE DEEP LOOK AT THE HARD X-RAY SKY: THE SWIFT-INTEGRAL X-RAY (SIX) SURVEY

    SciTech Connect

    Bottacini, Eugenio; Ajello, Marco

    2012-08-01

    The supermassive black holes at the center of active galactic nuclei (AGNs) are surrounded by obscuring matter that can block nuclear radiation. Depending on the amount of blocked radiation, the flux from the AGN can be too faint to be detected by currently flying hard X-ray (above 15 keV) missions. At these energies only {approx}1% of the intensity of the cosmic X-ray background (CXB) can be resolved into point-like sources that are AGNs. In this work, we address the question of undetected sources contributing to the CXB with a very sensitive and new hard X-ray survey: the Swift-INTEGRAL X-ray survey, which is obtained with the new approach of combining the Swift/BAT and INTEGRAL/IBIS X-ray observations. We merge the observations of both missions, which enhances the exposure time and reduces systematic uncertainties. As a result, we obtain a new survey over a wide sky area of 6200 deg{sup 2} that is more sensitive than the surveys of Swift/BAT or INTEGRAL/IBIS alone. Our sample comprises 113 sources: 86 AGNs (Seyfert-like and blazars), 5 galaxies, 2 clusters of galaxies, 3 Galactic sources, 3 previously detected unidentified X-ray sources, and 14 unidentified sources. The scientific outcome from the study of the sample has been properly addressed to study the evolution of AGNs at redshift below 0.4. We do not find any evolution using the 1/V{sub max} method. Our sample of faint sources is a suitable target for the new generation hard X-ray telescopes with focusing techniques.

  19. The Deep Look at the Hard X-Ray Sky: The Swift-INTEGRAL X-Ray (SIX) Survey

    NASA Astrophysics Data System (ADS)

    Bottacini, Eugenio; Ajello, Marco; Greiner, Jochen

    2012-08-01

    The supermassive black holes at the center of active galactic nuclei (AGNs) are surrounded by obscuring matter that can block nuclear radiation. Depending on the amount of blocked radiation, the flux from the AGN can be too faint to be detected by currently flying hard X-ray (above 15 keV) missions. At these energies only ~1% of the intensity of the cosmic X-ray background (CXB) can be resolved into point-like sources that are AGNs. In this work, we address the question of undetected sources contributing to the CXB with a very sensitive and new hard X-ray survey: the Swift-INTEGRAL X-ray survey, which is obtained with the new approach of combining the Swift/BAT and INTEGRAL/IBIS X-ray observations. We merge the observations of both missions, which enhances the exposure time and reduces systematic uncertainties. As a result, we obtain a new survey over a wide sky area of 6200 deg2 that is more sensitive than the surveys of Swift/BAT or INTEGRAL/IBIS alone. Our sample comprises 113 sources: 86 AGNs (Seyfert-like and blazars), 5 galaxies, 2 clusters of galaxies, 3 Galactic sources, 3 previously detected unidentified X-ray sources, and 14 unidentified sources. The scientific outcome from the study of the sample has been properly addressed to study the evolution of AGNs at redshift below 0.4. We do not find any evolution using the 1/V max method. Our sample of faint sources is a suitable target for the new generation hard X-ray telescopes with focusing techniques.

  20. NuSTAR Hard X-Ray Survey of the Galactic Center Region I: Hard X-Ray Morphology and Spectroscopy of the Diffuse Emission

    NASA Astrophysics Data System (ADS)

    Mori, Kaya; Hailey, Charles J.; Krivonos, Roman; Hong, Jaesub; Ponti, Gabriele; Bauer, Franz; Perez, Kerstin; Nynka, Melania; Zhang, Shuo; Tomsick, John A.; Alexander, David M.; Baganoff, Frederick K.; Barret, Didier; Barrière, Nicolas; Boggs, Steven E.; Canipe, Alicia M.; Christensen, Finn E.; Craig, William W.; Forster, Karl; Giommi, Paolo; Grefenstette, Brian W.; Grindlay, Jonathan E.; Harrison, Fiona A.; Hornstrup, Allan; Kitaguchi, Takao; Koglin, Jason E.; Luu, Vy; Madsen, Kristen K.; Mao, Peter H.; Miyasaka, Hiromasa; Perri, Matteo; Pivovaroff, Michael J.; Puccetti, Simonetta; Rana, Vikram; Stern, Daniel; Westergaard, Niels J.; Zhang, William W.; Zoglauer, Andreas

    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 (˜1023 cm-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 LX ≳ 1038 erg s-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 MWD ˜ 0.9 M⊙. 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.

  1. Fabricating Blazed Diffraction Gratings by X-Ray Lithography

    NASA Technical Reports Server (NTRS)

    Mouroulis, Pantazis; Hartley, Frank; Wilson, Daniel

    2004-01-01

    Gray-scale x-ray lithography is undergoing development as a technique for fabricating blazed diffraction gratings. As such, gray-scale x-ray lithography now complements such other grating-fabrication techniques as mechanical ruling, holography, ion etching, laser ablation, laser writing, and electron-beam lithography. Each of these techniques offers advantages and disadvantages for implementing specific grating designs; no single one of these techniques can satisfy the design requirements for all applications. Gray-scale x-ray lithography is expected to be advantageous for making gratings on steeper substrates than those that can be made by electron-beam lithography. This technique is not limited to sawtooth groove profiles and flat substrates: various groove profiles can be generated on arbitrarily shaped (including highly curved) substrates with the same ease as sawtooth profiles can be generated on flat substrates. Moreover, the gratings fabricated by this technique can be made free of ghosts (spurious diffraction components attributable to small spurious periodicities in the locations of grooves). The first step in gray-scale x-ray lithography is to conformally coat a substrate with a suitable photoresist. An x-ray mask (see Figure 1) is generated, placed between the substrate and a source of collimated x-rays, and scanned over the substrate so as to create a spatial modulation in the exposure of the photoresist. Development of the exposed photoresist results in a surface corrugation that corresponds to the spatial modulation and that defines the grating surface. The grating pattern is generated by scanning an appropriately shaped x-ray area mask along the substrate. The mask example of Figure 1 would generate a blazed grating profile when scanned in the perpendicular direction at constant speed, assuming the photoresist responds linearly to incident radiation. If the resist response is nonlinear, then the mask shape can be modified to account for the

  2. Investigation of the hard x-ray background in backlit pinhole imagersa)

    NASA Astrophysics Data System (ADS)

    Fein, J. R.; Peebles, J. L.; Keiter, P. A.; Holloway, J. P.; Klein, S. R.; Kuranz, C. C.; Manuel, M. J.-E.; Drake, R. P.

    2014-11-01

    Hard x-rays from laser-produced hot electrons (>10 keV) in backlit pinhole imagers can give rise to a background signal that decreases signal dynamic range in radiographs. Consequently, significant uncertainties are introduced to the measured optical depth of imaged plasmas. Past experiments have demonstrated that hard x-rays are produced when hot electrons interact with the high-Z pinhole substrate used to collimate the softer He-α x-ray source. Results are presented from recent experiments performed on the OMEGA-60 laser to further study the production of hard x-rays in the pinhole substrate and how these x-rays contribute to the background signal in radiographs. Radiographic image plates measured hard x-rays from pinhole imagers with Mo, Sn, and Ta pinhole substrates. The variation in background signal between pinhole substrates provides evidence that much of this background comes from x-rays produced in the pinhole substrate itself. A Monte Carlo electron transport code was used to model x-ray production from hot electrons interacting in the pinhole substrate, as well as to model measurements of x-rays from the irradiated side of the targets, recorded by a bremsstrahlung x-ray spectrometer. Inconsistencies in inferred hot electron distributions between the different pinhole substrate materials demonstrate that additional sources of hot electrons beyond those modeled may produce hard x-rays in the pinhole substrate.

  3. Investigation of the hard x-ray background in backlit pinhole imagers

    SciTech Connect

    Fein, J. R. Holloway, J. P.; Peebles, J. L.; Keiter, P. A.; Klein, S. R.; Kuranz, C. C.; Manuel, M. J.-E.; Drake, R. P.

    2014-11-15

    Hard x-rays from laser-produced hot electrons (>10 keV) in backlit pinhole imagers can give rise to a background signal that decreases signal dynamic range in radiographs. Consequently, significant uncertainties are introduced to the measured optical depth of imaged plasmas. Past experiments have demonstrated that hard x-rays are produced when hot electrons interact with the high-Z pinhole substrate used to collimate the softer He-α x-ray source. Results are presented from recent experiments performed on the OMEGA-60 laser to further study the production of hard x-rays in the pinhole substrate and how these x-rays contribute to the background signal in radiographs. Radiographic image plates measured hard x-rays from pinhole imagers with Mo, Sn, and Ta pinhole substrates. The variation in background signal between pinhole substrates provides evidence that much of this background comes from x-rays produced in the pinhole substrate itself. A Monte Carlo electron transport code was used to model x-ray production from hot electrons interacting in the pinhole substrate, as well as to model measurements of x-rays from the irradiated side of the targets, recorded by a bremsstrahlung x-ray spectrometer. Inconsistencies in inferred hot electron distributions between the different pinhole substrate materials demonstrate that additional sources of hot electrons beyond those modeled may produce hard x-rays in the pinhole substrate.

  4. The origin of the hard X-ray tail in neutron-star X-ray binaries

    NASA Astrophysics Data System (ADS)

    Reig, P.; Kylafis, N.

    2016-06-01

    Context. Neutron star X-ray binaries emit a compact, optically thick, relativistic radio jet during low-luminosity, usually hard states, as Galactic black-hole X-ray binaries do. When radio emission is bright, a hard power-law tail without evidence for an exponential cutoff is observed in most systems. Aims: We have developed a jet model that explains many spectral and timing properties of black-hole binaries in the states where a jet is present. Our goal is to investigate whether our jet model can reproduce the hard tail, with the correct range of photon index and the absence of a high-energy cutoff, in neutron-star X-ray binaries. Methods: We performed Monte Carlo simulations of the Compton upscattering of soft, accretion-disk or boundary layer photons in the jet and computed the emergent energy spectra, as well as the time lag of hard photons with respect to softer ones as a function of Fourier frequency. We fit the energy spectra with a power law modified by an exponential cutoff at high energy. Results: We demonstrate that our jet model naturally explains the observed power-law distribution with photon index in the range 1.8-3. With an appropriate choice of the parameters, the cutoff expected from Comptonization is shifted to energies above ~300 keV, producing a pure power law without any evidence for a rollover, in agreement with the observations. Conclusions: Our results reinforce the idea that the link between the outflow (jet) and inflow (disk) in X-ray binaries does not depend on the nature of the compact object, but on the process of accretion. Furthermore, we address the differences between jets in black-hole and neutron-star X-ray binaries and predict that the break frequency in the spectral energy distribution of neutron-star X-ray binaries, as a class, will be lower than that of black-hole binaries.

  5. X-ray emission from cataclysmic variables with accretion disks. I - Hard X-rays. II - EUV/soft X-ray radiation

    NASA Technical Reports Server (NTRS)

    Patterson, J.; Raymond, J. C.

    1985-01-01

    Theoretical models explaining the hard-X-ray, soft-X-ray, and EUV emission of accretion-disk cataclysmic variables in terms of the disk boundary layer (DBL) are developed on the basis of a survey of the published observational data. The data are compared with model predictions in graphs for systems with high or low (greater than or less than 10-Pg/s) accretion rates. Good agreement is obtained both at low accretion rates, where an optically thin rarefied hot (Te = 10 to the 8th K) DBL radiates most of its energy as hard X-rays, and at high accretion rates, where an optically thick 100,000-K DBL radiates most of its energy in the EUV and as soft X-rays. Detailed analysis of the old nova V603 Aql suggests that previous models predicting more detections of soft-X-ray/EUV emissions from thick-DBL objects (Ferland et al., 1982) used inappropriate dwarf masses, interstellar column densities, or classical-nova space densities.

  6. Curved focusing crystals for hard X-ray astronomy

    SciTech Connect

    Ferrari, C. Buffagni, E.; Bonnini, E.; Korytar, D.

    2013-12-15

    A lens made by a properly arranged array of crystals can be used to focus x-rays of energy ranging from 30 to 500 keV for x-ray astronomy. Mosaic or curved crystals can be employed as x-ray optical elements. In this work self standing curved focusing Si and GaAs crystals in which the lattice bending is induced by a controlled damaging process on one side of planar crystals are characterized. Diffraction profiles in Laue geometry have been measured in crystals at x-ray energies E = 17, 59 and 120 keV. An enhancement of diffraction efficiency is found in asymmetric geometries.

  7. Young Supernova explosions in the X-rays and hard X-rays

    NASA Astrophysics Data System (ADS)

    Margutti, Raffaella

    2016-04-01

    X-ray observations are providing critical insights into Supernova explosions and the nature of their progenitors. In this talk I will highlight some recent results from our dedicated programs at high-energies that allowed us to (1) uncover the weakest engine-driven SNe and understand their link to Gamma-Ray Bursts; (2) monitor the high-energy emission from shock energy deposition into the stellar envelope as early as a few days after the onset of core-collapse; (3) put the most stringent constraints to the progenitors of Type Ia SNe by using the deepest X-ray observations ever obtained. (4) Reveal the ejection of a massive stellar envelope timed with the collapse of a stripped star. These observations represent the first solid detection of a young extragalactic stripped-envelope SN out to high-energy X-rays of ˜40 keV

  8. Optimization of the hard X-ray self-seeding layout of the PAL-XFEL

    NASA Astrophysics Data System (ADS)

    Lee, Jaeyu; Hyun Shim, Chi; Yoon, Moohyun; Hwang, Ilmoon; Woon Parc, Yong; Wu, Juhao

    2015-10-01

    The Pohang Accelerator Laboratory X-ray free electron laser (PAL-XFEL) will operate a soft X-ray undulator line and a hard X-ray one during the initial operation period. For the hard X-ray line, self-seeding using a diamond crystal is the most promising approach to supply narrow bandwidth radiation to users. This paper presents simulation results for the optimization of the self-seeding layout in the hard X-ray undulator line for PAL-XFEL. The electron energy used in this study for the hard X-ray self-seeding scheme is 8.126 GeV and the central wavelength is 0.15 nm. The photon beam spectral bandwidth will be 0.78 eV by using the self-seeding option.

  9. First Images from HERO: A Hard-X-Ray Focusing Telescope

    NASA Technical Reports Server (NTRS)

    Ramsey, Brian D.; Alexander, Cheryl D.; Apple, Jeff A.; Benson, Carl M.; Dietz, Kurtis L.; Elsner, Ronald F.; Engelhaupt, Darell E.; Ghosh, Kajal K.; Kolodziejczak, Jeffery J.; ODell, Stephen L.; Whitaker, Ann F. (Technical Monitor)

    2001-01-01

    We are developing a balloon-borne hard-x-ray telescope that utilizes grazing incidence optics. Termed HERO, for High-Energy Replicated Optics, the instrument will provide unprecented sensitivity in the hard-x-ray region and will achieve milliCrab-level sensitivity in a typical 3-hour balloon-flight observation and 50 microCrab sensitivity on ultra-long-duration flights. A recent proof-of-concept flight, featuring a small number of mirror shells captured the first focused hard-x-ray images of galactic x-ray sources. Full details of the payload, its expected future performance and its recent measurements are provided.

  10. Hard X-ray Wiggler Front End Filter Design

    SciTech Connect

    Schulte-Schrepping, Horst; Hahn, Ulrich

    2007-01-19

    The front end filter design and implementation for the new HARWI-II hard X-ray wiggler at DORIS-III at HASYLAB/DESY is presented. The device emits a total power of 30 kW at 150mA storage ring current. The beam has a horizontal width of 3.8mrad and a central power density of 54 W/mm2 at 26m distance to the source. The filter section located in the ring tunnel has been introduced to tailor the thermal loads at the downstream optical components. The high power density and the high total power at the filter section are handled with a layered design. Glassy carbon filters convert the absorbed power into thermal radiation to lower the heat load to an acceptable level for water cooled copper filters. The requirements in beam size and filtering are addressed by separating the filter functions in three units which are switched individually into the beam.

  11. The hard X-ray burst spectrometer event listing, 1980 - 1985

    NASA Technical Reports Server (NTRS)

    Dennis, B. R.; Orwig, L. E.; Kiplinger, A. L.; Gibson, B. R.; Kennard, G. S.; Tolbert, A. K.

    1985-01-01

    This event listing is a comprehensive reference for the hard X-ray bursts detected with the Hard X-Ray Burst Spectrometer on the Solar Maximum Mission from the time of launch on February 14, 1980 to September 1985. Over 8000 X-ray events were detected in the energy range from 30 to approx. 500 keV with the vast majority being solar flares. The listing includes the start time, peak time, duration and peak rate of each event.

  12. The hard X-ray burst spectrometer event listing 1980-1987

    NASA Technical Reports Server (NTRS)

    Dennis, B. R.; Orwig, L. E.; Kiplinger, A. L.; Schwartz, R. A.; Gibson, B. R.; Kennard, G. S.; Tolbert, A. K.; Biesecker, D. A.; Labow, G. J.; Shaver, A.

    1988-01-01

    This event listing is a comprehensive reference for the Hard X-ray bursts detected with the Hard X-ray Burst Spectrometer on the Solar Maximum Mission from the time of launch 14 February 1980 to December 1987. Over 8600 X-ray events were detected in the energy range from 30 to approx. 600 keV with the vast majority being solar flares. The listing includes the start time, peak time, duration and peak rate of each event.

  13. The hard X-ray burst spectrometer event listing 1980, 1981 and 1982

    NASA Technical Reports Server (NTRS)

    Dennis, B. R.; Frost, K. J.; Orwig, L. E.; Kiplinger, A.; Dennis, H. E.; Gibson, B. R.; Kennard, G. S.; Tolbert, A. K.

    1983-01-01

    A comprehensive reference for the hard X-ray bursts detected with the Hard X-Ray Burst Spectrometer on the Solar Maximum Mission for the time of launch on February 14, 1980 to March 1983 is provided. Over 6300 X-ray events were detected in the energy range from 30 to approx 500 keV with the vast majority being solar flares. The listing includes the start time, peak time, duration and peak rate of each event.

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

    NASA Astrophysics Data System (ADS)

    Ramsey, Brian

    HERO, for High Energy Replicated Optics, is an evolutionary balloon payload featuring hard-xray 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 yer 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.

  15. Imaging the sun in hard x rays using Fourier telescopes

    NASA Technical Reports Server (NTRS)

    Campbell, J. W.

    1993-01-01

    For several years, solar flares have been observed with a variety of instruments confirming that tremendous amounts of energy are locally stored in the solar magnetic field and then rapidly released during the life of the flare. In concert with observations, theorists have attempted to describe the means by which these energetic events occur and evolve. Two competing theories have emerged and have stood the test of time. One theory describes the flare in terms of nonthermal, electron beam injection into a thick target while the other uses a thermal approach. Both theories provide results which are reasonably consistent with current observations; but to date, none have been able to provide conclusive evidence as to the validity of either model. Imaging on short time scales (1 s) and/or small size scales (1 arc s) should give definitive answers to these questions. In order to test whether a realistic telescope can indeed discriminate between models, we construct model sources based upon the thermal and the nonthermal models and calculate the emission as a function of time and energy in the range from 10 to 100 keV. In addition, we construct model telescopes representing both the spatial modulation collimator (SMC) and the rotating modulation collimator (RMC) techniques of observation using random photon counting statistics. With these two types of telescopes we numerically simulate the instrument response to the above two model flares to see if there are distinct x-ray signatures which may be discernable. We find that theoretical descriptions of the primary models of solar flares do indeed predict different hard x-ray signatures for 1 sec time scales and at 1-5 arc sec spatial resolution. However, these distinguishing signatures can best be observed early in the impulsive phase and from a position perpendicular to the plane of the loop. Furthermore, we find that Fourier telescopes with reasonable and currently attainable design characteristics can image these

  16. A bi-prism interferometer for hard x-ray photons

    SciTech Connect

    Isakovic, A.F.; Siddons, D.; Stein, A.; Warren, J.B.; Sandy, A.R.; Narayanan, M.S.; Ablett, J.M.; Metzler, M. and Evans-Lutterodt, K.

    2010-04-06

    Micro-fabricated bi-prisms have been used to create an interference pattern from an incident hard X-ray beam, and the intensity of the pattern probed with fluorescence from a 30 nm-thick metal film. Maximum fringe visibility exceeded 0.9 owing to the nano-sized probe and the choice of single-crystal prism material. A full near-field analysis is necessary to describe the fringe field intensities, and the transverse coherence lengths were extracted at APS beamline 8-ID-I. It is also shown that the maximum number of fringes is dependent only on the complex refractive index of the prism material.

  17. Off-plane x-ray reflection grating fabrication

    NASA Astrophysics Data System (ADS)

    Peterson, Thomas J.; DeRoo, Casey T.; Marlowe, Hannah; McEntaffer, Randall L.; Miles, Drew M.; Tutt, James H.; Schultz, Ted B.

    2015-09-01

    Off-plane X-ray diffraction gratings with precision groove profiles at the submicron scale will be used in next generation X-ray spectrometers. Such gratings will be used on a current NASA suborbital rocket mission, the Off-plane Grating Rocket Experiment (OGRE), and have application for future grating missions. The fabrication of these gratings does not come without challenges. High performance off-plane gratings must be fabricated with precise radial grating patterns, optically at surfaces, and specific facet angles. Such gratings can be made using a series of common micro-fabrication techniques. The resulting process is highly customizable, making it useful for a variety of different mission architectures. In this paper, we detail the fabrication method used to produce high performance off-plane gratings and report the results of a preliminary qualification test of a grating fabricated in this manner. The grating was tested in the off-plane `Littrow' configuration, for which the grating is most efficient for a given diffraction order, and found to achieve 42% relative efficiency in the blaze order with respect to all diffracted light.

  18. Kirkpatrick-Baez type x-ray focusing mirror fabricated by the bent-polishing method

    NASA Astrophysics Data System (ADS)

    Takeuchi, Akihisa; Suzuki, Yoshio; Takano, Hidekazu; Terada, Yasuko

    2005-09-01

    Microfocusing optics with total reflection mirrors has been constructed, and a performance test in the hard x-ray region has been carried out. The material of the mirror is fused quartz, and parabolic surface figures are fabricated by the bent-polishing method. The reflective surface is coated with platinum. By configuring two parabolic mirrors in the Kirkpatrick-Baez optics, a focused beam size of 150nm in the vertical direction ×110nm in the horizontal direction has been achieved at an x-ray energy of 12keV. A focused beam size of smaller than 300nm is obtained within an x-ray energy range of 8-28keV. In a performance test of the scanning microscope, fine periodic structures with a line pitch of 140nm are clearly resolved. Diffraction limit and modulation transfer function of these focusing optics are discussed.

  19. Kirkpatrick-Baez type x-ray focusing mirror fabricated by the bent-polishing method

    SciTech Connect

    Takeuchi, Akihisa; Suzuki, Yoshio; Takano, Hidekazu; Terada, Yasuko

    2005-09-15

    Microfocusing optics with total reflection mirrors has been constructed, and a performance test in the hard x-ray region has been carried out. The material of the mirror is fused quartz, and parabolic surface figures are fabricated by the bent-polishing method. The reflective surface is coated with platinum. By configuring two parabolic mirrors in the Kirkpatrick-Baez optics, a focused beam size of 150 nm in the vertical direction x110 nm in the horizontal direction has been achieved at an x-ray energy of 12 keV. A focused beam size of smaller than 300 nm is obtained within an x-ray energy range of 8-28 keV. In a performance test of the scanning microscope, fine periodic structures with a line pitch of 140 nm are clearly resolved. Diffraction limit and modulation transfer function of these focusing optics are discussed.

  20. Fabrication and evaluation of variable focus X-ray lenses.

    SciTech Connect

    Khounsary, A.; Dufresne, E. M.; Kewish, C. M.; Qian, J.; Assoufid, L.; Conley, R.; X-Ray Science Division; Illinois Inst. of Tech.

    2007-11-11

    We report on the fabrication, preliminary metrology, and X-ray transmission results of variable-focus cylindrical beryllium lenses. Each lens consists of a number of 1-mm-diameter lenslets made by precision computer numerical control (CNC) drilling into a beryllium substrate. The substrate is then cut into five parts, each having a different number of lenslets, ranging from 10 to 50. Each lens is then cut diagonally, using an electron discharge machine, to provide it with focusing ability. Unlike the traditional lenses having a fixed focal distance for a given energy, the present lenses provide for a wide range of photon energies and focal distances. Additionally, X-ray transmission through the lens is enhanced by reducing lenslet wall thickness to about 50 {micro}m, the thinnest reported to date.

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

    NASA Astrophysics Data System (ADS)

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

    2014-10-01

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

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

    SciTech Connect

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

    2014-10-10

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

  3. Hard X-ray Spectroscopic, Microwave and H-alpha Linear Polarization Studies with Hard X-Ray Observations from HESSI

    NASA Technical Reports Server (NTRS)

    Kiplinger, Alan L.

    2005-01-01

    The Principal Investigator (P.I.) has been pursuing a three year grant under NASA's Sun-Earth Connection Guest Investigator Program in support of the Ramaty High Energy Solar Spectroscopic Imager (RHESSI). An objective of these efforts is to combine X-ray and other data on solar flares, coronal mass ejections and interplanetary particle events in order to obtain a more comprehensive recognition of signatures, and understanding of interplanetary proton events. Thus, part of these efforts are to investigate if signatures seen in hard X-rays and microwaves can lead to better predictions of interplanetary proton events that can be dangerous to astronauts and spacecraft. The original proposal was written in May, 2000 and it discusses a three-pronged approach for data comparisons with three new types of instrumentation observing at X-ray, microwave and optical wavelengths. The major impetus behind this work and the proposal is that the P.I. discovered a strong correlation between a particular type of hard X-ray signature seen in spectral evolutions and interplanetary proton events (Kiplinger, 1995). The basic signature is that hard X-ray flux peaks either exhibit spectra that soften on their decays (Le. show fewer and fewer high energy X-rays with time) or they harden during decays (i.e. high energy X-rays decay significantly slower that lower energy X-rays). This signature is called progressive hardening. Studies were conducted over an eight-year period of data from the Hard X-Ray Burst Spectrometer (HXRBS) of the Solar maximum mission. Out of the 750 well observed flares studied, 41 flares had major associated proton events. Of these, 29 events were predicted on the basis of progressive hardening for a hit rate of 71%. The 152 largest flares had a hit rate of 82%.

  4. Compton polarimeter as a focal plane detector for hard X-ray telescope

    NASA Astrophysics Data System (ADS)

    Chattopadhyay, T.; Vadawale, S. V.

    X-ray polarimetry is expected to provide unique opportunity to study the behavior of matter and radiation under extreme magnetic fields and extreme gravitational fields. However sensitivity of the X-ray polarimeters has always been an issue for the last three decades; there is almost no progress in this field whereas there is a significant advance in the fields of X-ray spectroscopy, imaging and timing. Recently significant improvement in the sensitivity is expected in polarimetric measurements using GEM-based photoelectron tracking polarimeters coupled to soft X-ray telescopes. However they are sensitive in the soft X-ray regime. On the other hand mostly for the X-ray sources higher degree of polarisation at hard X-rays is expected because of the dominance of nonthermal X-ray emission mechanisms over the thermal counterpart. So polarisation measurement in hard X-ray can yield significant insights into such processes. Of late with the advent of high energy focussing telescopes (e.g. Nu STAR, ASTRO-H), sensitivity of X-ray detectors in hard X-ray range is expected to improve significantly. In this context we explore feasibility of a focal plane hard X-ray polarimeter based on Compton scattering having a thin plastic scatterer surrounded by cylindrical array of scintillator detectors. We have carried out detailed Geant4 simulations to estimate the modulation factor for 100% polarized beam as well as polarimetric efficiency of this configuration. Polarimetric sensitivity of the instrument critically depends on low energy threshold in central plastic scatterer. We estimated the sensitivity for a range of plastic threshold energy. We also discuss the methodology to measure the threshold energy in plastic scatterer. Here we present the initial results of polarisation sensitivities of such focal plane Compton polarimeter coupled with the reflection efficiency of present era hard X-ray optics and the experimental results for threshold measurements in plastic.

  5. The Swift-BAT Hard X-ray Transient Monitor

    NASA Technical Reports Server (NTRS)

    Krimm, Hans; Markwardt, C. B.; Sanwal, D.; Tueller, J.

    2006-01-01

    The Burst Alert Telescope (BAT) on the Swift satellite is a large field of view instrument that continually monitors the sky to provide the gamma-ray burst trigger for Swift. An average of more than 70% of the sky is observed on a daily basis. The survey mode data is processed on two sets on time scales: from one minute to one day as part of the transient monitor program, and from one spacecraft pointing (approx.20 minutes) to the full mission duration for the hard X-ray survey program. The transient monitor has recently become public through the web site http:// swift.gsfc.nasa.gov/docs/swift/results/transients/. Sky images are processed to detect astrophysical sources in the 15-50 keV energy band and the detected flux or upper limit is calculated for >100 sources on time scales up to one day. Light curves are updated each time that new BAT data becomes available (approx.10 times daily). In addition, the monitor is sensitive to an outburst from a new or unknown source. Sensitivity as a function of time scale for catalog and unknown sources will be presented. The daily exposure for a typical source is approx.1500-3000 seconds, with a 1-sigma sensitivity of approx.4 mCrab. 90% of the sources are sampled at least every 16 days, but many sources are sampled daily. It is expected that the Swift-BAT transient monitor will become an important resource for the high energy astrophysics community.

  6. Hard X-Ray bursts in collapse of supermassive stars

    NASA Astrophysics Data System (ADS)

    Barkov, M. V.

    2010-07-01

    The first stars in the Universe were verymassive, with masses as large as 106 M ⊙. They evolved into massive black holes (BH), which could have become the grains of the formation of supermassive BH in active galactic nuclei. If a supermassive star (SMS) rapidly rotates, it ends up as a supermassive collapsar and produces a magnetically accelerated jet. In this paper we discuss the possibility of the detection of hard X-ray bursts similar to gamma-ray bursts, which are associated with normal collapsars [1]. We demonstrate that in the process of the formation of a supecollapsar a jet may form via the Blandford-Znajek mechanism. The power of the jet may be as high as several 1051 erg/s and the total energy of the outburst may amount to 1056 erg. Due to the long time scales and large redshifts, the initial bright phase of the burstmay last for about 105 s, whereas the activity time of the central engine may be as long as 10 days. The large redshifts should make the spectrum softer compared to those of common gamma-ray bursts. The maximum of the spectral distribution should lie near 60 keV. The maximum flux is relatively small-on the order of several 10-7 erg/(cm-2 s)-but quite detectable. Such events for SMS should be rather rare: their occurence frequency must be of about 0.03/yr. Observations are to be carried out as long-term programs and will possibly be made in the future.

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

    PubMed

    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 <1.7' 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. PMID:25402988

  8. Hard x-ray response of pixellated CdZnTe detectors

    SciTech Connect

    Abbene, L.; Caccia, S.; Bertuccio, G.

    2009-06-15

    In recent years, the development of cadmium zinc telluride (CdZnTe) detectors for x-ray and gamma ray spectrometry has grown rapidly. The good room temperature performance and the high spatial resolution of pixellated CdZnTe detectors make them very attractive in space-borne x-ray astronomy, mainly as focal plane detectors for the new generation of hard x-ray focusing telescopes. In this work, we investigated on the spectroscopic performance of two pixellated CdZnTe detectors coupled with a custom low noise and low power readout application specific integrated circuit (ASIC). The detectors (10x10x1 and 10x10x2 mm{sup 3} single crystals) have an anode layout based on an array of 256 pixels with a geometric pitch of 0.5 mm. The ASIC, fabricated in 0.8 mum BiCMOS technology, is equipped with eight independent channels (preamplifier and shaper) and characterized by low power consumption (0.5 mW/channel) and low noise (150-500 electrons rms). The spectroscopic results point out the good energy resolution of both detectors at room temperature [5.8% full width at half maximum (FWHM) at 59.5 keV for the 1 mm thick detector; 5.5% FWHM at 59.5 keV for the 2 mm thick detector) and low tailing in the measured spectra, confirming the single charge carrier sensing properties of the CdZnTe detectors equipped with a pixellated anode layout. Temperature measurements show optimum performance of the system (detector and electronics) at T=10 deg.C and performance degradation at lower temperatures. The detectors and the ASIC were developed by our collaboration as two small focal plane detector prototypes for hard x-ray multilayer telescopes operating in the 20-70 keV energy range.

  9. Correlative Analysis of Hard and Soft X-ray Emissions in Solar Flares

    NASA Technical Reports Server (NTRS)

    Zarro, Dominic M.

    1997-01-01

    This report describes research performed under the Phase 3 Compton Gamma-Ray Observatory (CGRO) Guest Investigator Program. The objective of this work is to study different mechanisms of solar flare heating by comparing their predictions with simultaneous hard and soft X-ray observations. The datasets used in this work consist of hard X-ray observations from the CGRO Burst and Transient Source Experiment (BATSE) and soft X-ray observations from the Bragg Crystal Spectrometer (BCS) and Soft X-ray telescope (SXT) on the Japanese Yohkoh spacecraft.

  10. Coherent diffraction imaging using focused hard X-rays

    NASA Astrophysics Data System (ADS)

    Kim, Sunam; Kim, Sangsoo; Lee, Su Yong; Kim, Chan; Kim, Yoonhee; Noh, Do Young; Marathe, Shashidhara; Song, Changyong; Gallagher-Jones, Marcus; Kang, Hyon Chol

    2016-05-01

    A quantitative height profile image of a silicon nano-trench structure was obtained via coherent diffraction imaging (CDI) utilizing focused X-rays at a photon energy of 5.5 keV. The ability to optimize the spatial coherence and the photon flux density of a focused X-ray beam was the key technique for achieving such technical progress at a given X-ray photon flux. This was achieved by investigating the tunability of the focused beam's optical properties and performing a CDI experiment with the focused X-rays. The relationship between the focused X-rays' optical properties ( e.g., photon flux density and spatial coherence length) and the incident beam's size, which can be tuned by adjusting the slits in front of the Fresnel zone plate (FZP) was elucidated. We also obtained a quantitative image of a nano-trench sample produced via the reconstruction process of CDI, which utilizes carefully tuned, focused X-rays.

  11. Implications of stimulated resonant X-ray scattering for spectroscopy, imaging, and diffraction in the regime from soft to hard X-rays

    NASA Astrophysics Data System (ADS)

    Schreck, Simon; Beye, Martin; Föhlisch, Alexander

    2015-12-01

    The ultrahigh peak brilliance available at X-ray free-electron lasers opens the possibility to transfer nonlinear spectroscopic techniques from the optical and infrared into the X-ray regime. Here, we present a conceptual treatment of nonlinear X-ray processes with an emphasis on stimulated resonant X-ray scattering as well as a quantitative estimate for the scaling of stimulated X-ray scattering cross sections. These considerations provide the order of magnitude for the required X-ray intensities to experimentally observe stimulated resonant X-ray scattering for photon energies ranging from the extreme ultraviolet to the soft and hard X-ray regimes. At the same time, the regime where stimulated processes can safely be ignored is identified. With this basis, we discuss prospects and implications for spectroscopy, scattering, and imaging experiments at X-ray free-electron lasers.

  12. Fabrication of Metallic Magnetic Calorimeter X-ray Detector Arrays

    NASA Astrophysics Data System (ADS)

    Hsieh, W.-T.; Adams, J. A.; Bandler, S. R.; Beyer, J.; Denis, K. L.; Eguchi, H.; Figueroa-Feliciano, E.; Rotzinger, H.; Schneider, G. H.; Seidel, G. M.; Stevenson, T. R.; Travers, D. E.

    2008-04-01

    Microcalorimeters with metallic magnetic sensors show great promise for use in astronomical X-ray spectroscopy. We describe the design and fabrication of a lithographically patterned magnetic microcalorimeter. A paramagnetic AuEr film is sputter-deposited as the sensor, which is coupled to a low noise SQUID via a meander superconducting pickup loop used as an inductor. This inductor also provides the magnetic field bias to the sensor. The AuEr film is deposited over this meander such that the field created by a large current flowing in the loop magnetizes the sensor material. The use of thin film techniques in the fabrication of these magnetic sensors not only allows strong magnetic coupling between the sensor and the inductor, it also is scalable for array fabrication.

  13. THE HARD X-RAY BEHAVIOR OF AQL X-1 DURING TYPE-I BURSTS

    SciTech Connect

    Chen, Yu-Peng; Zhang, Shu; Zhang, Shuang-Nan; Ji, Long; Li, Jian; Wang, Jian-Min; Torres, Diego F.; Kretschmar, Peter E-mail: szhang@ihep.ac.cn

    2013-11-01

    We report the discovery of an anti-correlation between the soft and hard X-ray light curves of the X-ray binary Aql X-1 when bursting. This behavior may indicate that the corona is cooled by the soft X-ray shower fed by the type-I X-ray bursts, and that this process happens within a few seconds. Stacking the Aql X-1 light curves of type-I bursts, we find a shortage in the 40-50 keV band, delayed by 4.5 ± 1.4 s with respect to the soft X-rays. The photospheric radius expansion bursts are different in that neither a shortage nor an excess shows up in the hard X-ray light curve.

  14. Development of a prototype nickel optic for the Constellation-X hard x-ray telescope

    NASA Astrophysics Data System (ADS)

    Romaine, S.; Basso, S.; Bruni, R. J.; Burkert, W.; Citterio, O.; Cotroneo, V.; Engelhaupt, D.; Freyberg, M. J.; Gorenstein, P.; Gubarev, M.; Hartner, G.; Mazzoleni, F.; O'Dell, S.; Pareschi, G.; Ramsey, B. D.; Speegle, C.; Spiga, D.

    2007-09-01

    The Constellation-X mission concept has been streamlined to a single Atlas V 551 configuration. This decision was reached by the project team after considering the increases in launch costs announced in 2006 coupled with the constrained budget environment apparent with the release of the NASA 2007 budget. Along with the Spectroscopy X-ray Telescopes, this new configuration continues to carry a Hard X-ray Telescope (HXT) component, with some modifications to the original requirements to adjust to the new configuration. The total effective area requirement in the 7 - 40 keV band has been reduced, but at the same time the angular resolution requirement has been increased from 1 arcmin to 30 arcsec. The Smithsonian Astrophysical Observatory, Marshall Space Flight Center and Brera Observatory, Italy) have been collaborating to develop and HXT which meets the requirements of Constellation-X. The development work we have been engaged in to produce multilayer coated Electroformed-Nickel-Replicate (ENR) shells is well suited for this new configuration. We report here on results of fabrication and testing of a prototyped optic for the HXT. Full beam illumination X-ray tests, taken at MPE-Panter Test Facility, show that these optics meet the new requirement of 30 arcsec for the streamlined Constellation-X configuration. This report also presents preliminary results from studies using titanium nitride as a release agent to simplify and improve the nickel electroforming replication process.

  15. Fluence thresholds for grazing incidence hard x-ray mirrors

    SciTech Connect

    Aquila, A.; Ozkan, C.; Sinn, H.; Tschentscher, T.; Mancuso, A. P.; Gaudin, J.; Sobierajski, R.; Klepka, M. T.; Dłużewski, P.; Morawiec, K.; Störmer, M.; Bajt, S.; Ohashi, H.; Koyama, T.; Tono, K.; Inubushi, Y. [RIKEN and others

    2015-06-15

    X-ray Free Electron Lasers (XFELs) have the potential to contribute to many fields of science and to enable many new avenues of research, in large part due to their orders of magnitude higher peak brilliance than existing and future synchrotrons. To best exploit this peak brilliance, these XFEL beams need to be focused to appropriate spot sizes. However, the survivability of X-ray optical components in these intense, femtosecond radiation conditions is not guaranteed. As mirror optics are routinely used at XFEL facilities, a physical understanding of the interaction between intense X-ray pulses and grazing incidence X-ray optics is desirable. We conducted single shot damage threshold fluence measurements on grazing incidence X-ray optics, with coatings of ruthenium and boron carbide, at the SPring-8 Angstrom compact free electron laser facility using 7 and 12 keV photon energies. The damage threshold dose limits were found to be orders of magnitude higher than would naively be expected. The incorporation of energy transport and dissipation via keV level energetic photoelectrons accounts for the observed damage threshold.

  16. X-ray characterization of curved crystals for hard x-ray astronomy

    NASA Astrophysics Data System (ADS)

    Buffagni, Elisa; Bonnini, Elisa; Ferrari, Claudio; Virgilli, Enrico; Frontera, Filippo

    2015-05-01

    Among the methods to focus photons the diffraction in crystals results as one of the most effective for high energy photons. An assembling of properly oriented crystals can form a lens able to focus x-rays at high energy via Laue diffraction in transmission geometry; this is a Laue lens. The x-ray diffraction theory provides that the maximum diffraction efficiency is achieved in ideal mosaic crystals, but real mosaic crystals show diffraction efficiencies several times lower than the ideal case due to technological problems. An alternative and convenient approach is the use of curved crystals. We have recently optimized an efficient method based on the surface damage of crystals to produce self-standing uniformly curved Si, GaAs and Ge tiles of thickness up to 2-3 mm and curvature radii R down to a few meters. We show that, for curved diffracting planes, such crystals have a diffraction efficiency nearly forty times higher than the diffraction efficiency of perfect similar flat crystals, thus very close to that of ideal mosaic crystals. Moreover, in an alternative configuration where the diffracting planes are perpendicular to the curved ones, a focusing effect occurs and will be shown. These results were obtained for several energies between 17 and 120 keV with lab sources or at high energy facilities such as LARIX at Ferrara (Italy), ESRF at Grenoble (France), and ANKA at Karlsruhe (Germany).

  17. The High Energy X-ray Imager Technology (HEXITEC) for Solar Hard X-ray Observations

    NASA Astrophysics Data System (ADS)

    Christe, Steven; Shih, Albert Y.; Gaskin, Jessica; Wilson-Hodge, Colleen; Seller, Paul; Wilson, Matthew

    2015-04-01

    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 current high resolution X-ray mirrors, the HPD is about 25 arcsec. Over a 6-m focal length this converts to 750 µm, the optimum pixel size is around 250 µm. Annother requirement are that 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. For solar observations, the ability to handle high counting rates is also extremely desirable. The Rutherford Appleton Laboratory (RAL) in the UK has been developing the electronics for such a detector. Dubbed HEXITEC, for High Energy X-Ray Imaging Technology, this Application Specific Integrated Circuit (ASIC), 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. The NASA Marshall Space Flight CenterMSFC and the Goddard Space Flight Center (GSFC) has been working with RAL over the past few years to develop these detectors to be used with HXR focusing telescopes. We present on recent results and capabilities as applied to solar observations.

  18. Progress in the fabrication of high aspect ratio zone plates by soft x-ray lithography.

    SciTech Connect

    Divan, R.; Mancini, D. C.; Moldovan, N. A.; Lai, B.; Assoufid, L.; Leondard, Q.; Cerrina, F.

    2002-08-13

    Soft x-ray lithography technology has been applied to fabrication of phase shifting Fresnel Zone Plate (FZP's) for hard x-rays. Effects of the exposure conditions, developing system, and electroplating process parameters on line width and aspect ratio have been analyzed. The process has been optimized and an aspect ratio of 11 has been achieved for 110 nm outermost zone width. SEM and AFM have been used for preliminary metrology of the FZPs. The FZP optical performance was characterized at 8 keV photon energy at the 2-ID-D beam line at the Advanced Photon Source. Focusing efficiencies of 23% for FZPs apertures to 100 microns and 18% for 150-micron-diameter apertures have been obtained. The parameters of the fabricated FZP are in good agreement with the predicted values.

  19. Design of a hard X-ray beamline and end-station for pump and probe experiments at Pohang Accelerator Laboratory X-ray Free Electron Laser facility

    NASA Astrophysics Data System (ADS)

    Park, Jaeku; Eom, Intae; Kang, Tai-Hee; Rah, Seungyu; Nam, Ki Hyun; Park, Jaehyun; Kim, Sangsoo; Kwon, Soonam; Park, Sang Han; Kim, Kyung Sook; Hyun, Hyojung; Kim, Seung Nam; Lee, Eun Hee; Shin, Hocheol; Kim, Seonghan; Kim, Myong-jin; Shin, Hyun-Joon; Ahn, Docheon; Lim, Jun; Yu, Chung-Jong; Song, Changyong; Kim, Hyunjung; Noh, Do Young; Kang, Heung Sik; Kim, Bongsoo; Kim, Kwang-Woo; Ko, In Soo; Cho, Moo-Hyun; Kim, Sunam

    2016-02-01

    The Pohang Accelerator Laboratory X-ray Free Electron Laser project, a new worldwide-user facility to deliver ultrashort, laser-like x-ray photon pulses, will begin user operation in 2017 after one year of commissioning. Initially, it will provide two beamlines for hard and soft x-rays, respectively, and two experimental end-stations for the hard x-ray beamline will be constructed by the end of 2015. This article introduces one of the two hard x-ray end-stations, which is for hard x-ray pump-probe experiments, and primarily outlines the overall design of this end-station and its critical components. The content of this article will provide useful guidelines for the planning of experiments conducted at the new facility.

  20. Infrared identification of hard X-ray sources in the Galaxy

    NASA Astrophysics Data System (ADS)

    Nebot Gómez-Morán, A.; Motch, C.; Pineau, F.-X.; Carrera, F. J.; Pakull, M. W.; Riddick, F.

    2015-09-01

    The nature of the low- to intermediate-luminosity (LX ˜ 1032-34 erg s-1) source population revealed in hard band (2-10 keV) X-ray surveys of the Galactic plane is poorly understood. To overcome such problem, we cross-correlated the XMM-Newton 3XMM-DR4 survey with the infrared Two Micron All Sky Survey and Galactic Legacy Infrared Mid-Plane Survey Extraordinaire catalogues. We identified reliable X-ray-infrared associations for 690 sources. We selected 173 sources having hard X-ray spectra, typical of hard X-ray high-mass stars (kT > 5 keV), and 517 sources having soft X-ray spectra, typical of active coronae. About 18 per cent of the soft sources are classified in the literature: ˜91 per cent as stars, with a minor fraction of Wolf-Rayet (WR) stars. Roughly 15 per cent of the hard sources are classified in the literature: ˜68 per cent as high-mass X-ray stars single or in binary systems (WR, Be and high-mass X-ray binaries - HMXBs), with a small fraction of G and B stars. We carried out infrared spectroscopic pilot observations at the William Herschel Telescope for five hard X-ray sources. Three of them are high-mass stars with spectral types WN7-8h, Ofpe/WN9 and Be, and LX ˜ 1032-1033erg s-1. One source is a colliding-wind binary, while another source is a colliding-wind binary or a supergiant fast X-ray transient in quiescence. The Be star is a likely γ-Cas system. The nature of the other two X-ray sources is uncertain. The distribution of hard X-ray sources in the parameter space made of X-ray hardness ratio, infrared colours and X-ray-to-infrared flux ratio suggests that many of the unidentified sources are new γ-Cas analogues, WRs and low LX HMXBs. However, the nature of the X-ray population with Ks ≥ 11 and average X-ray-to-infrared flux ratio remains unconstrained.

  1. Fabricating High-Resolution X-Ray Collimators

    NASA Technical Reports Server (NTRS)

    Appleby, Michael; Atkinson, James E.; Fraser, Iain; Klinger, Jill

    2008-01-01

    A process and method for fabricating multi-grid, high-resolution rotating modulation collimators for arcsecond and sub-arcsecond x-ray and gamma-ray imaging involves photochemical machining and precision stack lamination. The special fixturing and etching techniques that have been developed are used for the fabrication of multiple high-resolution grids on a single array substrate. This technology has application in solar and astrophysics and in a number of medical imaging applications including mammography, computed tomography (CT), single photon emission computed tomography (SPECT), and gamma cameras used in nuclear medicine. This collimator improvement can also be used in non-destructive testing, hydrodynamic weapons testing, and microbeam radiation therapy.

  2. Suzaku Detection of Diffuse Hard X-Ray Emission Outside Vela X

    NASA Technical Reports Server (NTRS)

    Katsuda, Satoru; Mori, Koji; Petre, Robert; Yamaguchi, Hiroya; Tsunemi, Hiroshi; Bocchino, Fabrizio; Bamba, Aya; Miceli, Marco; Hewitt, John W.; Temim, Tea; Uchida, Hiroyuki; Yoshii, Rie

    2011-01-01

    Vela X is a large, 3 deg x 2 deg, radio-emitting pulsar wind nebula (PWN) powered by the Vela pulsar in the Vela supernova remnant. Using four Suzaku/XIS observations pointed just outside Vela X, we find hard X-ray emission extending throughout the fields of view. The hard X-ray spectra are well represented by a power-law. The photon index is measured to be constant at Gamma approximates 2.4, similar to that of the southern outer part of Vela X. The power-law flux decreases with increasing distance from the pulsar. These properties lead us to propose that the hard X-ray emission is associated with the Vela PWN. The larger X-ray extension found in this work strongly suggests that distinct populations relativistic electrons form the X-ray PWN and Vela X, as was recently inferred from multiwavelength spectral modeling of Vela X.

  3. The hard X-ray shortages prompted by the clock bursts in GS 1826-238

    SciTech Connect

    Ji, Long; Zhang, Shu; Chen, YuPeng; Zhang, Shuang-Nan; Li, Jian; Torres, Diego F.; Kretschmar, Peter

    2014-02-10

    We report on a study of GS 1826-238 using all available Rossi X-Ray Timing Explorer observations, concentrating on the behavior of the hard X-rays during type-I bursts. We find a hard X-ray shortage at 30-50 keV prompted by the shower of soft X-rays coming from type-I bursts. This shortage happens with a time delay after the peak of the soft flux of 3.6 ± 1.2 s. The behavior of hard X-rays during bursts indicates cooling and reheating of the corona, during which a large amount of energy is required. We speculate that this energy originates from the feedback of the type-I bursts to the accretion process, resulting in a rapid temporary increase of the accretion rate.

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

    NASA Astrophysics Data System (ADS)

    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.

  5. Introduction to a calibration facility for hard X-ray detectors

    NASA Astrophysics Data System (ADS)

    Zhou, Xu; Li, XinQiao; Xie, YaNing; Liu, CongZhan; Zhang, Shu; Wu, JinJie; Zhang, Jian; Li, XuFang; Zhang, YiFei; Li, Bing; Hu, HongLiang; Chen, YuPeng; Jiang, Wei; Li, ZeShu

    2014-12-01

    This paper introduces the current configuration of the Hard X-ray Calibration Facility (HXCF) in 2014, which is used to calibrate the high energy X-ray detectors that will be onboard the Hard X-ray Modulation Telescope (HXMT) satellite, China's first astronomy satellite. The HXCF consists of an X-ray tube, a skid platform system, a double crystal monochromator, a "T" structure mechanism, a collimator, an adjustable beam, a background shielding box, as well as the box of the control system. The HXCF covers 15-100 keV energy band and has a high fraction of monochromatic light (exceeding 92 % at 15-100 keV) and good monochromaticity (1‰ level). The flux of the monochromatic light is around 104 photons cm-2 s-1. This HXCF could be used to calibrate the energy linearities, the energy resolutions and detection efficiencies of hard X-ray detectors.

  6. Long-term variability in bright hard X-ray sources: 5+ years of BATSE data

    NASA Technical Reports Server (NTRS)

    Robinson, C. R.; Harmon, B. A.; McCollough, M. L.; Paciesas, W. S.; Sahi, M.; Scott, D. M.; Wilson, C. A.; Zhang, S. N.; Deal, K. J.

    1997-01-01

    The operation of the Compton Gamma Ray Observatory (CGRO)/burst and transient source experiment (BATSE) continues to provide data for inclusion into a data base for the analysis of long term variability in bright, hard X-ray sources. The all-sky capability of BATSE provides up to 30 flux measurements/day for each source. The long baseline and the various rising and setting occultation flux measurements allow searches for periodic and quasi-periodic signals with periods of between several hours to hundreds of days to be conducted. The preliminary results from an analysis of the hard X-ray variability in 24 of the brightest BATSE sources are presented. Power density spectra are computed for each source and profiles are presented of the hard X-ray orbital modulations in some X-ray binaries, together with amplitude modulations and variations in outburst durations and intensities in recurrent X-ray transients.

  7. Possible evidence for beaming in flares from microwave and hard X-ray imaging and spectra

    NASA Technical Reports Server (NTRS)

    Schmahl, E. J.; Kundu, M. R.; Dennis, B. R.

    1986-01-01

    The magnetic field strength and number of burst-producing energetic electrons are presently deduced for the impulsive phase of a solar flare at microwave wavelengths, with the VLA, and hard X-rays, with the SMM Hard X-ray Burst Spectrometer. The combined data indicate that the number of microwave-emitting electrons is at least three orders of magnitude smaller than the number of thick target electrons producing the hard X-rays; this is suggested to be due to the high beaming and inefficient radiation of gyrosynchrotron emission by comparison with isotropically distributed electrons.

  8. Observational techniques for solar flare gamma-rays, hard X-rays, and neutrons

    NASA Technical Reports Server (NTRS)

    Lin, Robert P.

    1989-01-01

    The development of new instrumentation and techniques for solar hard X-ray, gamma ray and neutron observations from spacecraft and/or balloon-borne platforms is examined. The principal accomplishments are: (1) the development of a two segment germanium detector which is near ideal for solar hard X-ray and gamma ray spectroscopy; (2) the development of long duration balloon flight techniques and associated instrumentation; and (3) the development of innovative new position sensitive detectors for hard X-ray and gamma rays.

  9. Development and Trial Measurements of Hard X-ray Photoelectron Emission Microscope

    SciTech Connect

    Taniuchi, T.; Oshima, M.; Wakita, T.; Takagaki, M.; Kawamura, N.; Suzuki, M.; Nakamura, T.; Kobayashi, K.; Akinaga, H.; Muraoka, H.; Ono, K.

    2007-01-19

    Photoelectron emission microscope (PEEM) study is performed using hard x-ray illumination. We have successfully obtained images with high spatial resolution of 40 nm with hard x-rays. Spectro-microscopy of Co micro-patterns on Si substrates, which can be applied to XAFS measurements on a minute scale by PEEM. Magnetic imaging has been demonstrated at the Pt L-edges on perpendicular magnetic recording pattern of CoCrPt alloy. These results are the first step toward a new spectroscopic microscopy and magnetic imaging in a hard x-ray region.

  10. Design, Fabrication and Testing of Multilayer Coated X-Ray Optics for the Water Window Imaging X-Ray Microscope

    NASA Technical Reports Server (NTRS)

    Spencer, Dwight C.

    1996-01-01

    Hoover et. al. built and tested two imaging Schwarzschild multilayer microscopes. These instruments were constructed as prototypes for the "Water Window Imaging X-Ray Microscope," which is a doubly reflecting, multilayer x-ray microscope configured to operate within the "water window." The "water window" is the narrow region of the x-ray spectrum between the K absorption edges of oxygen (lamda = 23.3 Angstroms) and of carbon (lamda = 43.62 Angstroms), where water is relatively highly transmissive and carbon is highly absorptive. This property of these materials, thus permits the use of high resolution multilayer x-ray microscopes for producing high contrast images of carbon-based structures within the aqueous physiological environments of living cells. We report the design, fabrication and testing of multilayer optics that operate in this regime.

  11. Using a 10-keV x-ray source for hardness assurance

    SciTech Connect

    Fleetwood, D.M.; Beegle, R.W.; Sexton, F.W.; Winokur, P.S.; Miller, S.L.; Schwank, J.R.; Jones, R.V.; McWhorter, P.J.

    1986-01-01

    It is shown that a 10 keV x-ray source can be used to predict the responses of microelectronic circuits to Co-60 irradiation. Guidelines for using an x-ray tester in a hardness assurance program for VLSI CMOS circuits are suggested. 5 refs., 2 figs., 1 tbl.

  12. Observations of hard X-rays along the ecliptic by the Sneg-2MP instrument

    NASA Astrophysics Data System (ADS)

    Rakhamimov, Sh. Iu.; Estulin, I. V.

    The paper develops a method for taking into account the contribution of activation to the hard X-rays observed along the ecliptic by the Sneg-2MP instrument aboard Prognoz-6. The possibility of observing X-ray sources in the 25-280 keV range is shown.

  13. The Interrelation of Soft and Hard X-ray Emission During Solar Flares

    NASA Technical Reports Server (NTRS)

    Fisher, George H.

    1997-01-01

    The objective of this project is to determine the characteristics of flare energy transport processes through the study of soft X-rays, hard X-rays, and their interrelationships through analysis of Yohkoh SXT, HXT, and BCS data, and comparison with theoretical models. The personnel involved in the research include SSL Assistant Research Physicists Dr. Peng Li and Dr. James McTiernan.

  14. Development of Prototype Nickel Optic for the Constellation-X Hard X-Ray Telescope

    NASA Astrophysics Data System (ADS)

    Romaine, S.; Gorenstein, P.; Bruni, R.; Pareschi, G.; Citterio, O.; Ghigo, M.; Mazzoleni, F.; Spiga, D.; Basso, S.; Conti, G.; Ramsey, B.; Gubarev, M.; O'Dell, S.; Speegle, C.; Engelhaupt, D.; Freyberg, M.; Burkert, W.; Hartner, G.

    2005-12-01

    The Constellation-X mission planned for launch in 2015, will feature an array of Hard X-ray telescopes (HXT) whose bandwidth extends to \\ 70 keV. Several technologies are being investigated for fabrication of these optics, including multilayer Coated Electroformed-Nickel-Replicated (ENR) shells. We are building a prototype HXT mirror module using an ENR process to fabricate the in dividual shells.This prototype consists of 5 shells with diameters ranging from 150 mm to 280 mm with a length of 426 mm. This paper presents a progress update and focuses on accomplishments during this past year. In particular, we will present results from high energy full illumination tests, taken at the MPE Panter Test Facility. This work was supported in part by NASA Grant NNG05WC27G and CONX/NASA grant 44A-1046805.

  15. Time-resolved hard x-ray spectrometer

    NASA Astrophysics Data System (ADS)

    Moy, Kenneth; Cuneo, Michael; McKenna, Ian; Keenan, Thomas; Sanford, Thomas; Mock, Ray

    2006-08-01

    Wired array studies are being conducted at the SNL Z accelerator to maximize the x-ray generation for inertial confinement fusion targets and high energy density physics experiments. An integral component of these studies is the characterization of the time-resolved spectral content of the x-rays. Due to potential spatial anisotropy in the emitted radiation, it is also critical to diagnose the time-evolved spectral content in a space-resolved manner. To accomplish these two measurement goals, we developed an x-ray spectrometer using a set of high-speed detectors (silicon PIN diodes) with a collimated field-of-view that converged on a 1-cm-diameter spot at the pinch axis. Spectral discrimination is achieved by placing high Z absorbers in front of these detectors. We built two spectrometers to permit simultaneous different angular views of the emitted radiation. Spectral data have been acquired from recent Z shots for the radial and axial (polar) views. UNSPEC 1 has been adapted to analyze and unfold the measured data to reconstruct the x-ray spectrum. The unfold operator code, UFO2, is being adapted for a more comprehensive spectral unfolding treatment.

  16. Time-Resolved Hard X-Ray Spectrometer

    SciTech Connect

    Kenneth Moya; Ian McKennaa; Thomas Keenana; Michael Cuneob

    2007-03-01

    Wired array studies are being conducted at the SNL Z accelerator to maximize the x-ray generation for inertial confinement fusion targets and high energy density physics experiments. An integral component of these studies is the characterization of the time-resolved spectral content of the x-rays. Due to potential spatial anisotropy in the emitted radiation, it is also critical to diagnose the time-evolved spectral content in a space-resolved manner. To accomplish these two measurement goals, we developed an x-ray spectrometer using a set of high-speed detectors (silicon PIN diodes) with a collimated field-of-view that converged on a 1-cm-diameter spot at the pinch axis. Spectral discrimination is achieved by placing high Z absorbers in front of these detectors. We built two spectrometers to permit simultaneous different angular views of the emitted radiation. Spectral data have been acquired from recent Z shots for the radial and polar views. UNSPEC1 has been adapted to analyze and unfold the measured data to reconstruct the x-ray spectrum. The unfold operator code, UFO2, is being adapted for a more comprehensive spectral unfolding treatment.

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

    PubMed

    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. PMID:19257417

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

    NASA Astrophysics Data System (ADS)

    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

  19. Radio observations of a hard X-ray selected sample of active galaxies

    NASA Technical Reports Server (NTRS)

    Unger, S. W.; Lawrence, A.; Wilson, A. S.; Elvis, M.; Wright, A. E.

    1987-01-01

    Radio observations of a hard X-ray selected sample of active galaxies obtained with the VLA and Parkes radio telescopes are discussed, and the ratio of the radio to X-ray flux density is used to determine the degree of radio-loudness of the galaxies. A continuous distribution of the degree of radio loudness is found amongst the sample galaxies, and no evidence for distinct radio-quiet and radio-loud populations is noted. The X-ray and radio luminosity is shown to be nonlinearly correlated, with the radio-loud objects all having high X-ray luminosity.

  20. Directional properties of hard x-ray sources generated by tightly focused ultrafast laser pulses

    SciTech Connect

    Hou Bixue; Mordovanakis, Aghapi; Easter, James; Krushelnick, Karl; Nees, John A.

    2008-11-17

    Directional properties of ultrafast laser-based hard x-ray sources are experimentally studied using tightly focused approximately millijoule laser pulses incident on a bulk Mo target. Energy distributions of K{alpha} and total x rays, as well as source-size distributions are directionally resolved in vacuum and in flowing helium, respectively. Directional distributions of x-ray emission is more isotropic for p-polarized pump than for s-polarized. Based on source-size measurements, a simple two-location model, with expanded plasma and bulk material, is employed to represent the x-ray source profile.

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

    NASA Technical Reports Server (NTRS)

    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.

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

    PubMed

    Müller, O; Lützenkirchen-Hecht, D; Frahm, R

    2015-03-01

    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. PMID:25832273

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

    SciTech Connect

    Müller, O. Lützenkirchen-Hecht, D.; Frahm, R.

    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.

  4. Non-thermal Hard X-Ray Emission from Coma and Several Abell Clusters

    SciTech Connect

    Correa, C

    2004-02-05

    We report results of hard X-Ray observations of the clusters Coma, Abell 496, Abell754, Abell 1060, Abell 1367, Abell2256 and Abell3558 using RXTE data from the NASA HEASARC public archive. Specifically we searched for clusters with hard x-ray emission that can be fitted by a power law because this would indicate that the cluster is a source of non-thermal emission. We are assuming the emission mechanism proposed by Vahk Petrosian where the inter cluster space contains clouds of relativistic electrons that by themselves create a magnetic field and emit radio synchrotron radiation. These relativistic electrons Inverse-Compton scatter Microwave Background photons up to hard x-ray energies. The clusters that were found to be sources of non-thermal hard x-rays are Coma, Abell496, Abell754 and Abell 1060.

  5. Hard X-rays for processing hybrid organic-inorganic thick films.

    PubMed

    Jiang, Yu; Carboni, Davide; Pinna, Alessandra; Marmiroli, Benedetta; Malfatti, Luca; Innocenzi, Plinio

    2016-01-01

    Hard X-rays, deriving from a synchrotron light source, have been used as an effective tool for processing hybrid organic-inorganic films and thick coatings up to several micrometres. These coatings could be directly modified, in terms of composition and properties, by controlled exposure to X-rays. The physico-chemical properties of the coatings, such as hardness, refractive index and fluorescence, can be properly tuned using the interaction of hard X-rays with the sol-gel hybrid films. The changes in the microstructure have been correlated especially with the modification of the optical and the mechanical properties. A relationship between the degradation rate of the organic groups and the rise of fluorescence from the hybrid material has been observed; nanoindentation analysis of the coatings as a function of the X-ray doses has shown a not linear dependence between thickness and film hardness. PMID:26698073

  6. The coevolution of decimetric millisecond spikes and hard X-ray emission during solar flares

    NASA Technical Reports Server (NTRS)

    Aschwanden, Markus J.; Guedel, Manuel

    1992-01-01

    Results are presented of an analysis of a comprehensive data set of 27 solar flares with decimetric millisecond spikes between 1980 and 1989, simultaneously observed with the Zuerich radio spectrometers and the Hard X-ray Burst Spectrometer on the SMM spacecraft. Two contradictory relationships of the coevolution of hard X-ray and spiky radio emissions during flares are found: the temporal evolution of both emissions reveals a close functional dependence, but there is a substantial time delay between the two emissions. Five possible scenarios for the hard-X-ray-associated radio spike emission which may account for both their detailed coevolution and their substantial intervening time delay are discussed. All five scenarios are able to explain both the close coevolution of hard X-ray and radio emission as well as their mutual delay to some degree, but none of them can explain all observational aspects in a simple way.

  7. Hard X-ray identification of η Carinae and steadiness close to periastron

    NASA Astrophysics Data System (ADS)

    Leyder, J.-C.; Walter, R.; Rauw, G.

    2010-12-01

    Context. The colliding-wind binary η Carinae exhibits soft X-ray thermal emission that varies strongly around the periastron passage. It has been found to have non-thermal emission, thanks to its detection in hard X-rays using INTEGRAL and Suzaku, and also in γ-rays with AGILE and Fermi. Aims: This paper attempts to definitively identify η Carinae as the source of the hard X-ray emission, to examine how changes in the 2-10 keV band influence changes in the hard X-ray band, and to understand more clearly the mechanisms producing the non-thermal emission using new INTEGRAL observations obtained close to periastron passage. Methods: To strengthen the identification of η Carinae with the hard X-ray source, a long Chandra observation encompassing the INTEGRAL/ISGRI error circle was analysed, and all other soft X-ray sources (including the outer shell of η Carinae itself) were discarded as likely counter-parts. To expand the knowledge of the physical processes governing the X-ray lightcurve, new hard X-ray images of η Carinae were studied close to periastron, and compared to previous observations far from periastron. Results: The INTEGRAL component, when represented by a power law (with a photon index Γ of 1.8), would produce more emission in the Chandra band than observed from any point source in the ISGRI error circle apart from η Carinae, as long as the hydrogen column density to the ISGRI source is lower than NH ≲ 1024 cm-2. Sources with such a high absorption are very rare, thus the hard X-ray emission is very likely to be associated with η Carinae. The eventual contribution of the outer shell to the non-thermal component also remains fairly limited. Close to periastron passage, a 3-σ detection is achieved for the hard X-ray emission of η Carinae, with a flux similar to the average value far from periastron. Conclusions: Assuming a single absorption component for both the thermal and non-thermal sources, this 3-σ detection can be explained with a

  8. Fabrication and Performance of a Lithium X-Ray Lens

    SciTech Connect

    Young, Kristina; Khounsary, Ali; Jansen, Andrew N.; Dufresne, Eric M.; Nash, Philip

    2007-01-19

    Compound refractive lenses (CRLs) are arrays of concave lenses whose simple design and ease in implementation and alignment make them an attractive optic to focus x-rays. Factors considered in designing CRLs include lens material, fabrication, and assembly. Lithium is a desirable material because it provides the largest index of refraction decrement per unit absorption length of any solid elements. Lithium is a difficult material to handle and fabricate because it is rather malleable and more importantly, it reacts with moisture, and to a lesser extent, with oxygen and nitrogen in air. It also tends to adhere to molds and dies.We report on the fabrication and performance of a parabolic lithium lens consisting of 32 lenslets. Lenslets are fabricated in a precision press using an indenter with a parabolic profile and a 100 {mu}m tip radius. The indenter is made of stainless steel and is figured using a computer numerically controlled (CNC) machine. The lens is designed to have a 1.7 m focal length at 10 keV energy. In an experiment conducted at the Advanced Photon Source (APS), a 0.5 mm x 0.5 mm monochromatic undulator beam strikes the lens. A focal length of 1.71, a focal spot size of 24 {mu}m x 34 {mu}m, and a peak intensity gain of over 18 are obtained.

  9. Solar flare hard X-ray spikes observed by RHESSI: a case study

    NASA Astrophysics Data System (ADS)

    Qiu, J.; Cheng, J. X.; Hurford, G. J.; Xu, Y.; Wang, H.

    2012-11-01

    Context. Fast-varying hard X-ray spikes of subsecond time scales were discovered by space telescopes in the 70s and 80s, and are also observed by the Ramaty High Energy Solar Spectroscopic Imager (RHESSI). These events indicate that the flare energy release is fragmented. Aims: In this paper, we analyze hard X-ray spikes observed by RHESSI to understand their temporal, spectral, and spatial properties. Methods: A recently developed demodulation code was applied to hard X-ray light curves in several energy bands observed by RHESSI. Hard X-ray spikes were selected from the demodulated flare light curves. We measured the spike duration, the energy-dependent time delay, and count spectral index of these spikes. We also located the hard X-ray source emitting these spikes from RHESSI mapping that was coordinated with imaging observations in visible and UV wavelengths. Results: We identify quickly varying structures of ≤ 1 s during the rise of hard X-rays in five flares. These hard X-ray spikes can be observed at photon energies over 100 keV. They exhibit sharp rise and decay with a duration (FWHM) of less than 1 s. Energy-dependent time lags are present in some spikes. It is seen that the spikes exhibit harder spectra than underlying components, typically by 0.5 in the spectral index when they are fitted to power-law distributions. RHESSI clean maps at 25-100 keV with an integration of 2 s centered on the peak of the spikes suggest that hard X-ray spikes are primarily emitted by double foot-point sources in magnetic fields of opposite polarities. With the RHESSI mapping resolution of ~4'', the hard X-ray spike maps do not exhibit detectable difference in the spatial structure from sources emitting underlying components. Coordinated high-resolution imaging UV and infrared observations confirm that hard X-ray spikes are produced in magnetic structures embedded in the same magnetic environment of the underlying components. The coordinated high-cadence TRACE UV

  10. Hard X-ray imaging of bacterial cells: nano-diffraction and ptychographic reconstruction.

    PubMed

    Wilke, R N; Priebe, M; Bartels, M; Giewekemeyer, K; Diaz, A; Karvinen, P; Salditt, T

    2012-08-13

    Ptychographic coherent X-ray diffractive imaging (PCDI) has been combined with nano-focus X-ray diffraction to study the structure and density distribution of unstained and unsliced bacterial cells, using a hard X-ray beam of 6.2keV photon energy, focused to about 90nm by a Fresnel zone plate lens. While PCDI provides images of the bacteria with quantitative contrast in real space with a resolution well below the beam size at the sample, spatially resolved small angle X-ray scattering using the same Fresnel zone plate (cellular nano-diffraction) provides structural information at highest resolution in reciprocal space up to 2nm(-1). We show how the real and reciprocal space approach can be used synergistically on the same sample and with the same setup. In addition, we present 3D hard X-ray imaging of unstained bacterial cells by a combination of ptychography and tomography. PMID:23038565

  11. Energetics and timing of the hard and soft X-ray emissions in white light flares

    NASA Technical Reports Server (NTRS)

    Neidig, Donald F.; Kane, Sharad R.

    1993-01-01

    By comparing the light curves in optical, hard X-ray, and soft X-ray wavelengths for eight well-observed flares, we confirm previous results indicating that the white light flare (WLF) is associated with the flare impulsive phase. The WLF emission peaks within seconds after the associated hard X-ray peak, and nearly two minutes before the 1-8 A soft X-ray peak. It is further shown that the peak power in nonthermal electrons above 50 keV is typically an order of magnitude larger, and the power in 1-8 A soft X-rays radiated over 2pi sr, at the time of the WLF peak, is an order of magnitude smaller than the peak WLF power.

  12. Work Towards Experimental Evidence Of Hard X-Ray Photoionization In Highly Charged Krypton

    SciTech Connect

    Silver, E.; Brickhouse, N. S.; Kirby, K.; Lin, T.; Gillaspy, J. D.; Gokhale, P.; Kanter, E. P.; Dunford, R. W.; Seifert, S.; Young, L.; McDonald, J.; Schneider, D.

    2011-06-01

    Ions of almost any charge state can be produced through electron-impact ionization. Here we describe our first experiments designed to photoionize these highly charged ions with hard x-rays by pairing an electron and photon beam. A spectral line at 12.7(1) keV with an intensity corroborated by theory may be the first evidence of hard x-ray photoionization of a highly charged ion.

  13. Work toward experimental evidence of hard x-ray photoionization in highly charged krypton.

    SciTech Connect

    Silver, E.; Gillaspy, J.D.; Gokhale, P.; Kanter, E.P.; Brickhouse, N.S.; Dunford, R.W.; Kirby, K.; Lin, T.; McDonald, J.; Schneider, D.; Seifert, S.; Young, L.

    2011-06-01

    Ions of almost any charge state can be produced through electron-impact ionization. Here we describe our first experiments designed to photoionize these highly charged ions with hard x-rays by pairing an electron and photon beam. A spectral line at 12.7(1) keV with an intensity corroborated by theory may be the first evidence of hard x-ray photoionization of a highly charged ion.

  14. The complete Hard X Ray Burst Spectrometer event list, 1980-1989

    NASA Technical Reports Server (NTRS)

    Dennis, B. R.; Orwig, L. E.; Kennard, G. S.; Labow, G. J.; Schwartz, R. A.; Shaver, A. R.; Tolbert, A. K.

    1991-01-01

    This event list is a comprehensive reference for all Hard X ray bursts detected with the Hard X Ray Burst Spectrometer on the Solar Maximum Mission from the time of launch on Feb. 14, 1980 to the end of the mission in Dec. 1989. Some 12,776 events were detected in the energy range 30 to 600 keV with the vast majority being solar flares. This list includes the start time, peak time, duration, and peak rate of each event.

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

    DOEpatents

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

    2001-01-01

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

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

    NASA Astrophysics Data System (ADS)

    Ding, G. Q.; Huang, C. P.

    2015-09-01

    Using the data from the Proportional Counter Array (PCA) and the High-Energy X-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 in the HEXTE spectra. The detected hard X-ray tails are discontinuously scattered throughout the Z track. The found hard X-ray tail hardens from the horizontal branch, through the normal branch, to the flaring branch in principle and it contributes ˜(20-50)% of the total flux in 20-200 keV. Our joint fitting results of the PCA + HEXTE spectra in 3-200 keV show that the portion of Comptonization in the Bulk-Motion Comptonization (BMC) model accounts for the hard X-ray tail, which indicates that the BMC process could be responsible for the detected hard tail. The temperature of the seed photons for BMC is ˜2.7 keV, implying that these seed photons might be emitted from the surface of the neutron star (NS) or the boundary layer between the NS and the disk and, therefore, this process could take place around the NS or in the boundary layer.

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

    NASA Technical Reports Server (NTRS)

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

    1993-01-01

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

  18. Sub-Picosecond Tunable Hard X-Ray Undulator Source for Laser/X-Ray Pump-Probe Experiments

    SciTech Connect

    Ingold, G.; Beaud, P.; Johnson, S.; Streun, A.; Schmidt, T.; Abela, R.; Al-Adwan, A.; Abramsohn, D.; Boege, M.; Grolimund, D.; Keller, A.; Krasniqi, F.; Rivkin, L.; Rohrer, M.; Schilcher, T.; Schmidt, T.; Schlott, V.; Schulz, L.; Veen, F. van der; Zimoch, D.

    2007-01-19

    The FEMTO source under construction at the {mu}XAS beamline is designed to enable tunable time-resolved laser/x-ray absorption and diffraction experiments in photochemistry and condensed matter with ps- and sub-ps resolution. The design takes advantage of (1) the highly stable operation of the SLS storage ring, (2) the reliable high harmonic operation of small gap, short period undulators to generate hard x-rays with energy 3-18 keV at 2.4 GeV beam energy, and (3) the progress in high power, high repetition rate fs solid-state laser technology to employ laser/e-beam 'slicing' to reach a time resolution of ultimately 100 fs. The source will profit from the inherently synchronized pump (laser I: 100 fs, 2 mJ, 1 kHz) and probe (sliced X-rays, laser II: 50 fs, 5 mJ, 1 kHz) pulses, and from the excellent stability of the SLS storage ring which is operated in top-up mode and controlled by a fast orbit feedback (FOFB). Coherent radiation emitted at THz frequencies by the sliced 100 fs electron bunches will be monitored as on-line cross-correlation signal to keep the laser-electron beam interaction at optimum. The source is designed to provide at 8 keV (100 fs) a monochromized flux of 104 ph/s/0.01% bw (Si crystal monochromator) and 106 ph/s/1.5% bw (multilayer monochromator) at the sample. It is operated in parasitic mode using a hybrid bunch filling pattern. Because of the low intensity measurements are carried out repetitively over many shots using refreshing samples and gated detectors. 'Diffraction gating' experiments will be used to characterize the sub-ps X-ray pulses.

  19. Hard X-ray imaging from the solar probe. [X ray telescope and mission planning

    NASA Technical Reports Server (NTRS)

    Hudson, H. S.

    1978-01-01

    The solar probe offers a platform with particular advantages for studying solar nonthermal plasma processes via the observations of hard X-radiation from energetic electrons in the chromosphere and corona, these include (1) high sensitivity, (2) a second line of sign (in addition to the earth's) that can aid in three dimensional reconstruction of the source distribution, and, (3) the possibility of correlation with direct measurements of the nonthermal particles from the probe itself.

  20. Hard X-ray AGN Clustering & SMBH Growth

    NASA Astrophysics Data System (ADS)

    Cappelluti, Nico

    2012-09-01

    In this review talk I present the status of the art of the studies on AGN clustering in the X-ray band and its applications in understanding the coeval growth of SMBH and Dark Matter Halos. A well defined picture has been taken up to z~2 while, at high-z, where important physical phenomena connected with SMBH formation, the knowledge is still relegated to the study of anisotropies of the unresolved CXB. I will finally present recent applications of clustering analysis to the study of clustering pattern in the unresolved CXB, and pointing out the possibility of the detection of the first BH in the University through fluctuation analysis.

  1. Performance of a hard x-ray undulator at CHESS

    SciTech Connect

    Bilderback, D. H.; Batterman, B. W.; Bedzyk, M. J.; Finkelstein, K.; Henderson, C.; Merlini, A.; Schildkamp, W.; Shen, Q.; White, J.; Blum, E. B.; and others

    1989-07-01

    A 3.3-cm period Nd-Fe-B hybrid undulator has been designed and successfully operated in the Cornell Electron Storage Ring (CESR). This 2-m-long, 123-pole insertion device is a prototype of one of the undulators planned for the Advanced Photon Source. In dedicated operation, the undulator produced the expected brightness at 5.437 GeV with the fundamental x-ray energy ranging from 4.3 to 7.9 keV corresponding to a change in gap from 1.5 to 2.8 cm.

  2. Temporal and spectral characteristics of solar flare hard X-ray emission

    NASA Technical Reports Server (NTRS)

    Dennis, B. R.; Kiplinger, A. L.; Orwig, L. E.; Frost, K. J.

    1985-01-01

    Solar Maximum Mission observations of three flares that impose stringent constraints on physical models of the hard X-ray production during the impulsive phase are presented. Hard X-ray imaging observations of the flares on 1980 November 5 at 22:33 UT show two patches in the 16 to 30 keV images that are separated by 70,000 km and that brighten simultaneously to within 5 s. Observations to O V from one of the footprints show simultaneity of the brightening in this transition zone line and in the total hard X-ray flux to within a second or two. These results suggest but do not require the existence of electron beams in this flare. The rapid fluctuations of the hard X-ray flux within some flares on the time scales of 1 s also provide evidence for electron beams and limits on the time scale of the energy release mechanism. Observations of a flare on 1980 June 6 at 22:34 UT show variations in the 28 keV X-ray counting rate from one 20 ms interval to the next over a period of 10 s. The hard X-ray spectral variations measured with 128 ms time resolution for one 0.5 s spike during this flare are consistent with the predictions of thick-target non-thermal beam model.

  3. High Precision Grids for Neutron, Hard X-Ray, and Gamma-Ray Imaging Systems

    NASA Technical Reports Server (NTRS)

    Campbell, Jonathan W. (Inventor)

    2002-01-01

    Fourier telescopes permit observations over a very broad band of energy. They generally include synthetic spatial filtering structures, known as multilayer grids or grid pairs consisting of alternate layers of absorbing and transparent materials depending on whether neutrons or photons are being imaged. For hard x-rays and gamma rays high (absorbing) and low (transparent) atomic number elements, termed high-Z and low-Z materials may be used. Fabrication of these multilayer grid structures is not without its difficulties. Herein the alternate layers of the higher material and the lower material are inserted in a polyhedron, transparent to photons of interest, through an open face of the polyhedron. The inserted layers are then uniformly compressed to form a multilayer grid.

  4. High-resolution projection image reconstruction of thick objects by hard x-ray diffraction microscopy

    SciTech Connect

    Takahashi, Yukio; Nishino, Yoshinori; Tsutsumi, Ryosuke; Zettsu, Nobuyuki; Matsubara, Eiichiro; Yamauchi, Kazuto; Ishikawa, Tetsuya

    2010-12-01

    Hard x-ray diffraction microscopy enables us to observe thick objects at high spatial resolution. The resolution of this method is limited, in principle, by only the x-ray wavelength and the largest scattering angle recorded. As the resolution approaches the wavelength, the thickness effect of objects plays a significant role in x-ray diffraction microscopy. In this paper, we report high-resolution hard x-ray diffraction microscopy for thick objects. We used highly focused coherent x rays with a wavelength of {approx}0.1 nm as an incident beam and measured the diffraction patterns of a {approx}150-nm-thick silver nanocube at the scattering angle of {approx}3 deg. We observed a characteristic contrast of the coherent diffraction pattern due to only the thickness effect and collected the diffraction patterns at nine incident angles so as to obtain information on a cross section of Fourier space. We reconstructed a pure projection image by the iterative phasing method from the patched diffraction pattern. The edge resolution of the reconstructed image was {approx}2 nm, which was the highest resolution so far achieved by x-ray microscopy. The present study provides us with a method for quantitatively observing thick samples at high resolution by hard x-ray diffraction microscopy.

  5. Fabrication of Microcoils Using X-ray Lithography and Metallizaiton

    NASA Astrophysics Data System (ADS)

    Noda, Daiji; Matsumoto, Yoshifumi; Setomoto, Masaru; Hattori, Tadashi

    Coils and actuators are finding an increasing number of uses in various fields. The demand for microcoils and microactuators is increasing due to the recent progress in downsizing and the increasing sophistication of various industrial products. Actuators account for a large percentage of the total volume and weight of many product compared with other parts and devices that are typically included. However, coils are unsuitable for miniaturization because of their structure. Therefore, we have proposed the use of high aspect ratio microcoils in order to reduce their size and to increase their performance. To realize microcoils such as these, we have developed a fabrication process based on three-dimensional deep X-ray lithography and metallization techniques. We have also used a dipping method in order to obtain thick layers of photoresist on metal bar with diameters of 1 mm. In this paper, we have fabricated microcoils with 10 μm line widths, 20 μm pitch, and aspect ratio of over 5. There is every expectation that high performance microcoils with high aspect ratio coil lines could be manufactured by this process, despite their miniature size.

  6. Angular resolution measurements at SPring-8 of a hard x-ray optic for the New Hard X-ray Mission

    NASA Astrophysics Data System (ADS)

    Spiga, D.; Raimondi, L.; Furuzawa, A.; Basso, S.; Binda, R.; Borghi, G.; Cotroneo, V.; Grisoni, G.; Kunieda, H.; Marioni, F.; Matsumoto, H.; Mori, H.; Miyazawa, T.; Negri, B.; Orlandi, A.; Pareschi, G.; Salmaso, B.; Tagliaferri, G.; Uesugi, K.; Valsecchi, G.; Vernani, D.

    2011-09-01

    The realization of X-ray telescopes with imaging capabilities in the hard (> 10 keV) X-ray band requires the adoption of optics with shallow (< 0.25 deg) grazing angles to enhance the reflectivity of reflective coatings. On the other hand, to obtain large collecting area, large mirror diameters (< 350 mm) are necessary. This implies that mirrors with focal lengths >=10 m shall be produced and tested. Full-illumination tests of such mirrors are usually performed with onground X-ray facilities, aimed at measuring their effective area and the angular resolution; however, they in general suffer from effects of the finite distance of the X-ray source, e.g. a loss of effective area for double reflection. These effects increase with the focal length of the mirror under test; hence a "partial" full-illumination measurement might not be fully representative of the in-flight performances. Indeed, a pencil beam test can be adopted to overcome this shortcoming, because a sector at a time is exposed to the X-ray flux, and the compensation of the beam divergence is achieved by tilting the optic. In this work we present the result of a hard X-ray test campaign performed at the BL20B2 beamline of the SPring-8 synchrotron radiation facility, aimed at characterizing the Point Spread Function (PSF) of a multilayer-coated Wolter-I mirror shell manufactured by Nickel electroforming. The mirror shell is a demonstrator for the NHXM hard X-ray imaging telescope (0.3 - 80 keV), with a predicted HEW (Half Energy Width) close to 20 arcsec. We show some reconstructed PSFs at monochromatic X-ray energies of 15 to 63 keV, and compare them with the PSFs computed from post-campaign metrology data, self-consistently treating profile and roughness data by means of a method based on the Fresnel diffraction theory. The modeling matches the measured PSFs accurately.

  7. Achromatic nested Kirkpatrick–Baez mirror optics for hard X-ray nanofocusing

    PubMed Central

    Liu, Wenjun; Ice, Gene E.; Assoufid, Lahsen; Liu, Chian; Shi, Bing; Khachatryan, Ruben; Qian, Jun; Zschack, Paul; Tischler, Jonathan Z.; Choi, J.-Y.

    2011-01-01

    The first test of nanoscale-focusing Kirkpatrick–Baez (KB) mirrors in the nested (or Montel) configuration used at a hard X-ray synchrotron beamline is reported. The two mirrors are both 40 mm long and coated with Pt to produce a focal length of 60 mm at 3 mrad incident angle, and collect up to a 120 µm by 120 µm incident X-ray beam with maximum angular acceptance of 2 mrad and a broad bandwidth of energies up to 30 keV. In an initial test a focal spot of about 150 nm in both horizontal and vertical directions was achieved with either polychromatic or monochromatic beam. The nested mirror geometry, with two mirrors mounted side-by-side and perpendicular to each other, is significantly more compact and provides higher demagnification than the traditional sequential KB mirror arrangement. Ultimately, nested mirrors can focus larger divergence to improve the diffraction limit of achromatic optics. A major challenge with the fabrication of the required mirrors is the need for near-perfect mirror surfaces near the edge of at least one of the mirrors. Special polishing procedures and surface profile coating were used to preserve the mirror surface quality at the reflecting edge. Further developments aimed at achieving diffraction-limited focusing below 50 nm are underway. PMID:21685674

  8. Achromatic nested Kirkpatrick-Baez mirror optics for hard x-ray nanofocusing.

    SciTech Connect

    Liu, W.; Ice, G. E.; Assoufid, L.; Liu, C.; Shi, B.; Khachatryan, R.; Qian, J.; Zschack, P.; Tischler, J. Z.; Choi, J.-Y.

    2011-07-01

    The first test of nanoscale-focusing Kirkpatrick-Baez (KB) mirrors in the nested (or Montel) configuration used at a hard X-ray synchrotron beamline is reported. The two mirrors are both 40 mm long and coated with Pt to produce a focal length of 60 mm at 3 mrad incident angle, and collect up to a 120 {micro}m by 120 {micro}m incident X-ray beam with maximum angular acceptance of 2 mrad and a broad bandwidth of energies up to 30 keV. In an initial test a focal spot of about 150 nm in both horizontal and vertical directions was achieved with either polychromatic or monochromatic beam. The nested mirror geometry, with two mirrors mounted side-by-side and perpendicular to each other, is significantly more compact and provides higher demagnification than the traditional sequential KB mirror arrangement. Ultimately, nested mirrors can focus larger divergence to improve the diffraction limit of achromatic optics. A major challenge with the fabrication of the required mirrors is the need for near-perfect mirror surfaces near the edge of at least one of the mirrors. Special polishing procedures and surface profile coating were used to preserve the mirror surface quality at the reflecting edge. Further developments aimed at achieving diffraction-limited focusing below 50 nm are underway.

  9. Achromatic nested Kirkpatrick-Baez mirror optics for hard X-ray nanofocusing.

    PubMed

    Liu, Wenjun; Ice, Gene E; Assoufid, Lahsen; Liu, Chian; Shi, Bing; Khachatryan, Ruben; Qian, Jun; Zschack, Paul; Tischler, Jonathan Z; Choi, J Y

    2011-07-01

    The first test of nanoscale-focusing Kirkpatrick-Baez (KB) mirrors in the nested (or Montel) configuration used at a hard X-ray synchrotron beamline is reported. The two mirrors are both 40 mm long and coated with Pt to produce a focal length of 60 mm at 3 mrad incident angle, and collect up to a 120 µm by 120 µm incident X-ray beam with maximum angular acceptance of 2 mrad and a broad bandwidth of energies up to 30 keV. In an initial test a focal spot of about 150 nm in both horizontal and vertical directions was achieved with either polychromatic or monochromatic beam. The nested mirror geometry, with two mirrors mounted side-by-side and perpendicular to each other, is significantly more compact and provides higher demagnification than the traditional sequential KB mirror arrangement. Ultimately, nested mirrors can focus larger divergence to improve the diffraction limit of achromatic optics. A major challenge with the fabrication of the required mirrors is the need for near-perfect mirror surfaces near the edge of at least one of the mirrors. Special polishing procedures and surface profile coating were used to preserve the mirror surface quality at the reflecting edge. Further developments aimed at achieving diffraction-limited focusing below 50 nm are underway. PMID:21685674

  10. Achromatic Nested Kirkpatrick-Baez Mirror Optics for Hard X-ray Nanofocusing

    SciTech Connect

    Liu, Wenjun; Ice, Gene E; Assoufid, Lahsen; Liu, Chian; Shi, B.; Khachatryan, Ruben; Qian, J; Zshack, Dr Paul; Tischler, Jonathan Zachary; Choi, Jae-Young

    2011-01-01

    The first test of nanoscale-focusing Kirkpatrick-Baez (KB) mirrors in the nested (or Montel) configuration used at a hard X-ray synchrotron beamline is reported. The two mirrors are both 40 mm long and coated with Pt to produce a focal length of 60 mm at 3 mrad incident angle, and collect up to a 120 {micro}m by 120 {micro}m incident X-ray beam with maximum angular acceptance of 2 mrad and a broad bandwidth of energies up to 30 keV. In an initial test a focal spot of about 150 nm in both horizontal and vertical directions was achieved with either polychromatic or monochromatic beam. The nested mirror geometry, with two mirrors mounted side-by-side and perpendicular to each other, is significantly more compact and provides higher demagnification than the traditional sequential KB mirror arrangement. Ultimately, nested mirrors can focus larger divergence to improve the diffraction limit of achromatic optics. A major challenge with the fabrication of the required mirrors is the need for near-perfect mirror surfaces near the edge of at least one of the mirrors. Special polishing procedures and surface profile coating were used to preserve the mirror surface quality at the reflecting edge. Further developments aimed at achieving diffraction-limited focusing below 50 nm are underway.

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

    NASA Technical Reports Server (NTRS)

    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.

  12. CdTe focal plane detector for hard x-ray focusing optics

    NASA Astrophysics Data System (ADS)

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

    2015-08-01

    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 mm x 20 mm CdTe-based detector with 250 μm square pixels (80x80 pixels) which achieves 1 keV FWHM @ 60 keV and gives full spectroscopy between 5 keV and 200 keV. An added advantage of these detectors is that they have a full-frame readout rate of 10 kHz. Working with NASA Goddard Space Flight Center and Marshall Space Flight Center, 4 of these 1mm-thick CdTe detectors are tiled into a 2x2 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 flightsuitable 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.

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

    NASA Astrophysics Data System (ADS)

    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.

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

    SciTech Connect

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

    2011-03-28

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

  15. Observation of a Soft Tissue by a Zernike Phase Contrast Hard X-ray Microscope

    SciTech Connect

    Aoki, Sadao; Namikawa, Tadahiro; Hoshino, Masato; Watanabe, Norio

    2007-01-19

    A Zernike-type phase contrast hard X-ray microscope was constructed at the Photon Factory BL3C2 (KEK). A white beam from a bending magnet was monochromatized by a silicon double crystal monochromator. Monochromatic parallel X-ray beam illuminated a sample, and transmitted and diffracted X-ray beams were imaged by a Fresnel zone plate (FZP) which had the outer zone width of 100 nm. A phase plate made of a thin aluminum foil with a pinhole was set at the back focal plane of the FZP. The phase plate modulated the diffraction beam from the FZP, whereas a direct beam passed through the pinhole. The resolution of the microscope was measured by observing a tantalum test pattern at an X-ray energy of 9 keV. A 100nm line-and-space pattern could be resolved. X-ray montage pictures of growing eggs of artemia (plankton) were obtained.

  16. Guidelines for using a 10-keV x-ray source for hardness assurance

    SciTech Connect

    Fleetwood, D.M.

    1986-01-01

    In this paper, work done at Sandia is summarized that demonstrates that it is possible to use a 10-keV x-ray source for hardness assurance. Transistor data is presented that shows that a 10-keV x-ray source can be used as a reliable process monitor, in the sense that Co-60 part response can be predicted easily and reliably from x-ray part response. Further, test structure and functional part data is presented that illustrates how an x-ray source may be employed for wafer lot acceptance for silicon-gate CMOS devices that either employ quardbands or hardened field oxides for device isolation. Finally, a few words are said about the use of high-Z gate metallizations. These results should provide guidelines for implementation of lot acceptance testing with a 10-keV x-ray source.

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

    PubMed

    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. PMID:26725662

  18. Development of microperiodic mirrors for hard x-ray phase-contrast imaging

    SciTech Connect

    Stutman, Dan; Finkenthal, Michael; Moldovan, Nicolae

    2010-09-01

    Differential phase-contrast imaging with hard x rays can have important applications in medicine, material sciences, and energy research. Phase-contrast methods based on microperiodic optics, such as shearing interferometry, are particularly attractive because they allow the use of conventional x-ray tubes. To enable shearing interferometry with x rays up to 100 keV, we propose using grazing-incidence microperiodic mirrors. In addition, a simple lithographic method is proposed for the production of the microperiodic x-ray mirrors, based on the difference in grazing-incidence reflectivity between a low-Z substrate and a high-Z film. Using this method, we produced prototype mirrors with 5-100 {mu}m periods and 90 mm active length. Experimental tests with x rays up to 60 keV indicate good microperiodic mirror reflectivity and high-contrast fringe patterns, encouraging further development of the proposed imaging concept.

  19. Observation of a Soft Tissue by a Zernike Phase Contrast Hard X-ray Microscope

    NASA Astrophysics Data System (ADS)

    Aoki, Sadao; Namikawa, Tadahiro; Hoshino, Masato; Watanabe, Norio

    2007-01-01

    A Zernike-type phase contrast hard X-ray microscope was constructed at the Photon Factory BL3C2 (KEK). A white beam from a bending magnet was monochromatized by a silicon double crystal monochromator. Monochromatic parallel X-ray beam illuminated a sample, and transmitted and diffracted X-ray beams were imaged by a Fresnel zone plate (FZP) which had the outer zone width of 100 nm. A phase plate made of a thin aluminum foil with a pinhole was set at the back focal plane of the FZP. The phase plate modulated the diffraction beam from the FZP, whereas a direct beam passed through the pinhole. The resolution of the microscope was measured by observing a tantalum test pattern at an X-ray energy of 9 keV. A 100nm line-and-space pattern could be resolved. X-ray montage pictures of growing eggs of artemia (plankton) were obtained.

  20. Solar flares with similar soft but different hard X-ray emissions: case and statistical studies

    NASA Astrophysics Data System (ADS)

    Sharykin, Ivan N.; Struminsky, Alexei B.; Zimovets, Ivan V.; Gan, Wei-Qun

    2016-01-01

    From the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) catalog we select events which have approximately the same GOES class (high C - low M or 500-1200 counts s-1 within the RHESSI 6-12 keV energy band), but with different maximal energies of detected hard X-rays. The selected events are subdivided into two groups: (1) flares with X-ray emissions observed by RHESSI up to only 50 keV and (2) flares with hard X-ray emission observed also above 50 keV. The main task is to understand observational peculiarities of these two flare groups. We use RHESSI X-ray data to obtain spectral and spatial information in order to find differences between selected groups. Spectra and images are analyzed in detail for six events (case study). For a larger number of samples (85 and 28 flares in the low-energy and high-energy groups respectively) we only make some generalizations. In spectral analysis we use the thick-target model for hard X-ray emission and one temperature assumption for thermal soft X-ray emission. RHESSI X-ray images are used for determination of flare region sizes. Although thermal and spatial properties of these two groups of flares are not easily distinguishable, power law indices of hard X-rays show significant differences. Events from the high-energy group generally have a harder spectrum. Therefore, the efficiency of chromospheric evaporation is not sensitive to the hardness of nonthermal electron spectra but rather depends on the total energy flux of nonthermal electrons.

  1. RF photoinjector development for a short-pulse, hard x-ray Thomson scattering source

    SciTech Connect

    Le Sage, G P; Anderson, S G; Cowan, T E; Crane, J K; Ditmire, T; Rosenzweig, J B

    2000-08-15

    An important motivation in the development of the next generation x-ray light sources is to achieve picosecond and sub-ps pulses of hard x-rays for dynamic studies of a variety of physical, chemical and biological processes. Present hard x-ray sources are either pulse-width or intensity limited, which allows ps-scale temporal resolution only for signal averaging of highly repetitive processes. A much faster and brighter hard x-ray source is being developed at LLNL, based on Thomson scattering of fs-laser pulses by a relativistic electron beam, which will enable x-ray characterization of the transient structure of a sample in a single shot. Experimental and diagnostic techniques relevant to the development of next generation sources including the Linac Coherent Light Source can be tested with the Thomson scattering hard x-ray source. This source will combine an RF photoinjector with a 100 MeV S-band linac. The photoinjector and linac also provide an ideal test-bed for examining space-charge induced emittance growth effects. A program of beam dynamics and diagnostic experiments are planned in parallel with Thomson source development. Our experimental progress and future plans will be discussed.

  2. Fabricating sub-collimating grids for an x-ray solar imaging spectrometer using LIGA techniques

    SciTech Connect

    Brennen, R.A.; Hecht, M.H.; Wiberg, D.V.

    1997-04-01

    The HESSI mission proposes to perform high resolution imaging and spectroscopy observations in the soft X-ray, hard X-ray, and gamma-ray regimes, with finer angular resolution (nearly 2 arcseconds) and finer energy resolution (approximately 1 keV) than has been previously possible. This combination of imaging and spectroscopy is achieved with a set of Rotating Modulation Collimators placed in front of an array of cooled germanium and silicon detectors. A set of 12 bi-grid collimators, each of which consists of a pair of identically pitched, widely-separated grids, is used to provide the imaging. Each grid consists of a planar array of equally-spaced, parallel, X-ray opaque slats separated by X-ray transparent slits. If the slits of each grid are parallel to each other and the pitch is identical for the two grids, then the transmission through the grid pair depends on the direction of incidence of the incoming X-rays. For slits and slats of equal width, the transmission varies between zero and 50% depending on whether the shadows of the slats in the top grid fall on the slits or slats of the lower grid. A complete transmission cycle from zero to 50% and back to zero corresponds to a change in source direction that is given by p/L, where L is the separation between the grids. The authors describe a deep etch lithography technique developed to fabricate the grids which have pitches below 100 {micro}m. They use a free standing sheet of PMMA as a base for the process, and use the ALS facility to perform the exposures of the PMMA.

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

    PubMed

    Kojima, Sadaoki; Ikenouchi, Takahito; Arikawa, Yasunobu; Sakata, Shohei; Zhang, Zhe; Abe, Yuki; Nakai, Mitsuo; Nishimura, Hiroaki; Shiraga, Hiroyuki; Ozaki, Tetsuo; Miyamoto, Shuji; Yamaguchi, Masashi; Takemoto, Akinori; Fujioka, Shinsuke; Azechi, Hiroshi

    2016-04-01

    Hard X-ray spectroscopy is an essential diagnostics used to understand physical processes that take place in high energy density plasmas produced by intense laser-plasma interactions. A bundle of hard X-ray detectors, of which the responses have different energy thresholds, is used as a conventional single-shot spectrometer for high-flux (>10(13) photons/shot) hard X-rays. However, high energy resolution (Δhv/hv < 0.1) is not achievable with a differential energy threshold (DET) X-ray spectrometer because its energy resolution is limited by energy differences between the response thresholds. Experimental demonstration of a Compton X-ray spectrometer has already been performed for obtaining higher energy resolution than that of DET spectrometers. In this paper, we describe design details of the Compton X-ray spectrometer, especially dependence of energy resolution and absolute response on photon-electron converter design and its background reduction scheme, and also its application to the laser-plasma interaction experiment. The developed spectrometer was used for spectroscopy of bremsstrahlung X-rays generated by intense laser-plasma interactions using a 200 μm thickness SiO2 converter. The X-ray spectrum obtained with the Compton X-ray spectrometer is consistent with that obtained with a DET X-ray spectrometer, furthermore higher certainly of a spectral intensity is obtained with the Compton X-ray spectrometer than that with the DET X-ray spectrometer in the photon energy range above 5 MeV. PMID:27131669

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

    NASA Astrophysics Data System (ADS)

    Kojima, Sadaoki; Ikenouchi, Takahito; Arikawa, Yasunobu; Sakata, Shohei; Zhang, Zhe; Abe, Yuki; Nakai, Mitsuo; Nishimura, Hiroaki; Shiraga, Hiroyuki; Ozaki, Tetsuo; Miyamoto, Shuji; Yamaguchi, Masashi; Takemoto, Akinori; Fujioka, Shinsuke; Azechi, Hiroshi

    2016-04-01

    Hard X-ray spectroscopy is an essential diagnostics used to understand physical processes that take place in high energy density plasmas produced by intense laser-plasma interactions. A bundle of hard X-ray detectors, of which the responses have different energy thresholds, is used as a conventional single-shot spectrometer for high-flux (>1013 photons/shot) hard X-rays. However, high energy resolution (Δhv/hv < 0.1) is not achievable with a differential energy threshold (DET) X-ray spectrometer because its energy resolution is limited by energy differences between the response thresholds. Experimental demonstration of a Compton X-ray spectrometer has already been performed for obtaining higher energy resolution than that of DET spectrometers. In this paper, we describe design details of the Compton X-ray spectrometer, especially dependence of energy resolution and absolute response on photon-electron converter design and its background reduction scheme, and also its application to the laser-plasma interaction experiment. The developed spectrometer was used for spectroscopy of bremsstrahlung X-rays generated by intense laser-plasma interactions using a 200 μm thickness SiO2 converter. The X-ray spectrum obtained with the Compton X-ray spectrometer is consistent with that obtained with a DET X-ray spectrometer, furthermore higher certainly of a spectral intensity is obtained with the Compton X-ray spectrometer than that with the DET X-ray spectrometer in the photon energy range above 5 MeV.

  5. Laser Pulse Circulation System for Compact Monochromatic Tunable Hard X-Ray Source

    NASA Astrophysics Data System (ADS)

    Ogino, Haruyuki; de, Meng; Yamamoto, Tomohiko; Sakamoto, Fumito; Dobashi, Katsuhiro; Uesaka, Mitsuru

    2007-09-01

    We are construcing a laser electron Compton scattering monochromatic tunable hard X-ray source. It consists of the X-band (11.424 GHz) electron linear accelerator and Q-switch Nd:YAG laser. This work is a part of the JST(Japan Science and Technology Agency) project. The whole system is a part of the national project on the advanced compact medical accelerator development, hosted by NIRS(National Institute for Radiological Science). The University of Tokyo and KEK are working for the X-ray source. Main advantage of this X-ray source is monochromatic tunable hard X-rays(10-50keV) with the intensities of 108-109 photons/s. The table-top size X-ray source can generate dual energy monochromatic hard X-ray by turns and it takes about 40ms to chage the X-ray energy. It is calculated that the X-ray intensity is 107 photons/RF-pulse (108 photons/s in 10 pps) by the 35MeV electron and YAG laser(2J/pulse). The X-band beam line for the demonstration is under construction. We designed a laser pulse circulation system to increase the X-ray yield 10 times higer (up to 108 photons/RF-pulse, 109 photons/s). It can be proved that the laser total energy increases 10 times higher by the principle experiment with the lower energy laser (25mJ/pulse).

  6. Laser Pulse Circulation System for Compact Monochromatic Tunable Hard X-Ray Source

    NASA Astrophysics Data System (ADS)

    Ogino, Haruyuki; de, Meng; Yamamoto, Tomohiko; Sakamoto, Fumito; Dobashi, Katsuhiro; Uesaka, Mitsuru

    We are construcing a laser electron Compton scattering monochromatic tunable hard X-ray source. It consists of the X-band (11.424 GHz) electron linear accelerator and Q-switch Nd:YAG laser. This work is a part of the JST (Japan Science and Technology Agency) project. The whole system is a part of the national project on the advanced compact medical accelerator development, hosted by NIRS (National Institute for Radiological Science). The University of Tokyo and KEK are working for the X-ray source. Main advantage of this X-ray source is monochromatic tunable hard X-rays (10-50keV) with the intensities of 108-109 photons/s. The table-top size X-ray source can generate dual energy monochromatic hard X-ray by turns and it takes about 40ms to chage the X-ray energy. It is calculated that the X-ray intensity is 107 photons/RF-pulse (108 photons/s in 10 pps) by the 35MeV electron and YAG laser (2J/pulse). The X-band beam line for the demonstration is under construction. We designed a laser pulse circulation system to increase the X-ray yield 10 times higer (up to 108 photons/RF-pulse, 109 photons/s). It can be proved that the laser total energy increases 10 times higher by the principle experiment with the lower energy laser (25mJ/pulse).

  7. Development of a prototype nickel optic for the Constellation-X hard x-ray telescope

    NASA Astrophysics Data System (ADS)

    Romaine, Suzanne E.; Basso, Stefano; Bruni, Ricardo J.; Citterio, Oberto; Engelhaupt, Darell; Ghigo, Mauro; Gorenstein, Paul; Gubarev, Mikhail V.; Mazzoleni, Francesco; O'Dell, Stephen L.; Pareschi, Giovanni; Parodi, Giancarlo; Ramsey, Brian D.; Speegle, Chet O.

    2004-02-01

    The Constellation-X mission, planned for launch in 2013, will feature an array of hard-x-ray telescopes (HXT) with a total collecting area of greater than 1500 cm2 at 40 keV. Two technologies are currently being investigated for the optics of these telescopes including multilayer-coated Eletroformed-Nickel-Replicated (ENR) shells. The attraction of the ENR process is that the resulting full-shell optics are inherently stable and offer the prospect of better angular resolution which results in lower background and higher instrument sensitivity. The challenge for this process is to meet a relatively tight weight budget with a relatively dense material (ρnickel = 9 g/cm3.) To demonstrate the viability of the ENR process we are fabricating a prototype HXT mirror module to be tested against a competing segmented-glass-shell optic. The ENR prototype will consist of 5 shells of diameters from 150 mm to 280 mm with a length of 426 mm. To meet the stringent weight budget for Con-X, the shells will range in thickness from 100 microns to 150 microns. The innermost of these will be coated with Iridium, while the remainder will be coated with graded-dspaced W/Si multilayers. Mandrels for these shells are in the fabrication stage, the first test shells have been produced and are currently undergoing tests for figure and microroughness. A tentative date of June '04 has been set for the prototype X-ray testing at MSFC. Issues currently being addressed are the control of stresses in the multiplayer coating and ways of mitigating their effects on the figure of the necessarily thin shells. The fabrication, handling and mounting of these shells must be accomplished without inducing permanent figure distortions. A full status report on the prototype optic will be presented along with test results as available.

  8. eHXI: A permanently installed, hard x-ray imager for the National Ignition Facility

    DOE PAGESBeta

    Doppner, T.; Bachmann, B.; Albert, F.; Bell, P.; Burns, S.; Celeste, J.; Chow, R.; Divol, L.; Dewald, E. L.; Hohenberger, M.; et al

    2016-06-14

    We have designed and built a multi-pinhole imaging system for high energy x-rays (≥ 50 keV) that is permanently installed in the equatorial plane outside of the target chamber at the National Ignition Facility (NIF). It records absolutely-calibrated, time-integrated x-ray images with the same line-of-sight as the multi-channel, spatially integrating hard x-ray detector FFLEX [McDonald et al., Rev. Sci. Instrum. 75 (2004) 3753], having a side view of indirect-drive inertial confinement fusion (ICF) implosion targets. The equatorial hard x-ray imager (eHXI) has recorded images on the majority of ICF implosion experiments since May 2011. Lastly, eHXI provides valuable information onmore » hot electron distribution in hohlraum experiments, target alignment, potential hohlraum drive asymmetries and serves as a long term reference for the FFLEX diagnostics.« less

  9. Hard X-Rays from a Complete Sample of the Brightest Ultraluminous Infrared Galaxies

    NASA Technical Reports Server (NTRS)

    Sanders, David B.

    2003-01-01

    We were awarded 70kS of XMM-Newton spacecraft time using the Epic pn camera to observe three ultraluminous infrared galaxies (ULIGs) in order to measure the spectral shape of their hard X-Ray emission, and to use this information to search for the presence of an highly obscured active galactic nucleus (AGN), and to separate out the contributions from a putative starburst. By observing three objects we hope to be able to better assess the role of AGN in the complete class of ULIGs and therefore to better constrain their contribution to the X-ray background. XMM-Newton was deemed to be better suited to our proposed measurements of ULIGs than the Chandra X-ray observatory due to its larger aperture and better sensitivity to hard (2-10 keV) X-rays.

  10. Interrelation of soft and hard X-ray emissions during solar flares. I - Observations

    NASA Technical Reports Server (NTRS)

    Winglee, R. M.; Kiplinger, A. L.; Zarro, D. M.; Dulk, G. A.; Lemen, J. R.

    1991-01-01

    The interrelation between the acceleration and heating of electrons and ions during impulsive solar flares is determined on the basis of simulataneous observations of hard and soft X-ray emission from the Solar Maximum Mission at high time resolution (6 s). For all the flares, the hard X-rays are found to have a power-law spectrum which breaks down during the rise phase and beginning of the decay phase. After that, the spectrum changes to either a single power law or a power law that breaks up at high energies. The characteristics of the soft X-ray are found to depend on the flare position. It is suggested that small-scale quasi-static electric fields are important for determining the acceleration of the X-ray-producing electrons and the outflowing chromospheric ions.

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

    NASA Technical Reports Server (NTRS)

    Beilicke, M.; Binns, W. R.; Buckley, J.; Cowsik, R.; Dowkontt, P.; Garson, A.; Guo, Q.; Israel, M. H.; Lee, K.; Krawczynski, H.; Baring, M. G.; Barthelmy, S.; Okajima, T.; Schnittman, J.; Tueller, J.; Haba, Y.; Kunieda, H.; Matsumoto, H.; Miyazawa, T.; Tamura, K.

    2011-01-01

    X-ray polarimetry promises to give 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 keV 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.

  12. Thick-target bremsstrahlung interpretation of short time-scale solar hard X-ray features

    NASA Technical Reports Server (NTRS)

    Emslie, A. G.

    1983-01-01

    Steady-state analyses of bremsstrahlung hard X-ray production in solar flares are appropriate only if the lifetime of the high energy electrons in the X-ray source is much shorter than the duration of the observed X-ray burst. For a thick-target nonthermal model, this implies that a full time-dependent analysis is required when the duration of the burst is comparable to the collisional lifetime of the injected electrons, in turn set by the lengths and densities of the flaring region. In this paper we present the results of such a time-dependent analysis, and we point out that the intrinsic temporal signature of the thick-target production mechanism, caused by the finite travel time of the electrons through the target, may indeed rule out such a mechanism for extremely short duration hard X-ray events.

  13. eHXI: a permanently installed, hard x-ray imager for the National Ignition Facility

    NASA Astrophysics Data System (ADS)

    Döppner, T.; Bachmann, B.; Albert, F.; Bell, P.; Burns, S.; Celeste, J.; Chow, R.; Divol, L.; Dewald, E. L.; Hohenberger, M.; Huntington, C. M.; Izumi, N.; LaCaille, G.; Landen, O. L.; Palmer, N.; Park, H.-S.; Thomas, C. A.

    2016-06-01

    We have designed and built a multi-pinhole imaging system for high energy x-rays (>= 50 keV) that is permanently installed in the equatorial plane outside of the target chamber at the National Ignition Facility (NIF). It records absolutely-calibrated, time-integrated x-ray images with the same line-of-sight as the multi-channel, spatially integrating hard x-ray detector FFLEX [McDonald et al., Rev. Sci. Instrum. 75 (2004) 3753], having a side view of indirect-drive inertial confinement fusion (ICF) implosion targets. The equatorial hard x-ray imager (eHXI) has recorded images on the majority of ICF implosion experiments since May 2011. eHXI provides valuable information on hot electron distribution in hohlraum experiments, target alignment, potential hohlraum drive asymmetries and serves as a long term reference for the FFLEX diagnostics.

  14. Sapphire hard X-ray Fabry-Perot resonators for synchrotron experiments.

    PubMed

    Tsai, Yi Wei; Wu, Yu Hsin; Chang, Ying Yi; Liu, Wen Chung; Liu, Hong Lin; Chu, Chia Hong; Chen, Pei Chi; Lin, Pao Te; Fu, Chien Chung; Chang, Shih Lin

    2016-05-01

    Hard X-ray Fabry-Perot resonators (FPRs) made from sapphire crystals were constructed and characterized. The FPRs consisted of two crystal plates, part of a monolithic crystal structure of Al2O3, acting as a pair of mirrors, for the backward reflection (0 0 0 30) of hard X-rays at 14.3147 keV. The dimensional accuracy during manufacturing and the defect density in the crystal in relation to the resonance efficiency of sapphire FPRs were analyzed from a theoretical standpoint based on X-ray cavity resonance and measurements using scanning electron microscopic and X-ray topographic techniques for crystal defects. Well defined resonance spectra of sapphire FPRs were successfully obtained, and were comparable with the theoretical predictions. PMID:27140144

  15. Development of High Resolution Hard X-Ray Telescope with Multilayer Coatings

    NASA Technical Reports Server (NTRS)

    Brinton, John C. (Technical Monitor); Gorenstein, Paul

    2004-01-01

    The major objective of this program is the development of a focusing hard X-ray telescope with moderately high angular resolution, i .e. comparable to the telescopes of XMM-Newton. The key ingredients of the telescope are a depth graded multilayer coatings and electroformed nickel substrates that are considerably lighter weight than those of previous missions such as XMM-Newton, which have had conventional single metal layer reflective coatings and have operated at much lower energy X-rays. The ultimate target mission for this technology is the Hard X-Ray Telescope (HXT) of the Constellation X-Ray Mission. However, it is applicable to potential SMEX and MIDEX programs as well.

  16. Spectral and Timing Investigations of Dwarf Novae Selected in Hard X-Rays

    NASA Technical Reports Server (NTRS)

    Thorstensen, John; Remillard, Ronald A.

    2000-01-01

    There are 9 dwarf novae (DN) among the 43 cataclysmic variables (accreting white dwarfs in close binary systems) that were detected during the HEAO-1 all-sky X-ray survey (1977-1979). On the other hand, there are roughly one hundred dwarf novae that are closer and/or optically brighter and yet they were not detected as hard X-ray sources. Two of the HEAO-1 DN show evidence for X-ray pulsations that imply strong magnetic fields on the white dwarf surface, and magnetic CVs are known to be strong X-ray sources. However, substantial flux in hard X-rays may be caused by non-magnetic effects, such as an optically thin boundary layer near a massive white dwarf. We proposed RXTE observations to measure plasma temperatures and to search for X-ray pulsations. The observations would distinguish whether these DN belong to one of (rare) magnetic subclasses. For those that do not show pulsations, the observations support efforts to define empirical relations between X-ray temperature, the accretion rate, and the mass of the white dwarf. The latter is determined via optical studies of the dynamics of the binary constituents.

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

    PubMed

    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. PMID:18278127

  18. Target optimisation for the yield of X-rays of desired hardness under femtosecond pulse irradiation

    NASA Astrophysics Data System (ADS)

    Brantov, A. V.; Lobok, M. G.; Bychenkov, V. Yu

    2016-04-01

    Different regimes of electron acceleration from solid foils and low-density targets are investigated using three-dimensional numerical simulations. The size of the plasma corona is shown to be the main parameter characterising the temperature and number of hot electrons, which determine the yield of X-ray radiation and its hardness. Also studied is the generation of X-ray radiation by laseraccelerated electrons, which bombard the converter target located behind the laser target.

  19. Upper limits from hard X-ray observations of five BL Lacertae objects

    NASA Technical Reports Server (NTRS)

    Bezler, M.; Gruber, D. E.; Rothschild, R. E.

    1988-01-01

    Results are presented from hard X-ray observations of the five brightest X-ray BL Lacertae objects: PKS 0548-322, Mrk 421 (=1101+384), 2A 1219+305, Mrk 501 (=1652+398), and PKS 2155-304. The observations covered the energy range 15-165 keV from August 1977 to December 1978. The results are compared with previous studies.

  20. High-performance multilevel blazed x-ray microscopy Fresnel zone plates: Fabricated using x-ray lithography

    SciTech Connect

    Di Fabrizio, E.; Gentili, M.; Grella, L.; Baciocchi, M. , I-00156 Rome ); Krasnoperova, A.; Cerrina, F. ); Yun, W.; Lai, B.; Gluskin, E. )

    1994-11-01

    Diffractive lenses are becoming the optical elements of choice for many applications. One type of diffractive lens, the binary zone plate, has already demonstrated high-resolution performance experimentally. However, in order to increase the diffraction efficiency of these zone plates, a blazed grating profile must be used. This can best be approximated by a staircase grating profile, created by multilevel exposures. Using x-ray lithograph, we fabricated for the first time circular, linear bi- and trilevel zone plates, with gold structures 0.75 [mu]m thick (per level), on silicon nitride substrates. The zone plates were designed for use at a wavelength of 1.54 A, and had a theoretical efficiency of 68.5% for bilevel and 81.5% for trilevel zone plates. Due to the large depth of focus and high resolution inherent to x-ray lithography, the finished zone plate exhibits very steep sidewall profiles, with linewidth resolution down to 0.25 [mu]m. Such vertical sidewalls are essential for achieving high lens efficiency. Fabrication errors, such as thickness variation in the electroplated gold and misalignment, were considered, and their effect on the optical efficiency of the zone plate was estimated. Alignment errors between levels were minimized, achieving a best result of 25 nm (3[sigma]). In fabricating the zone plates, we employed standard integrated device tools, such as a Leica Cambridge Electron Beam microfabricator (EBMF) 10cs/120 electron-beam writer for the x-ray mask fabrication, and a Suss 200 x-ray stepper for the multilevel exposures. Thus, we have shown that it will be possible to fabricate many lenses, with a variety of optical characteristics, in one wafer.

  1. An Ultra-High Pressure Proportional Counter for Hard X-Ray Astronomy.

    NASA Astrophysics Data System (ADS)

    Ye, Zongnan

    1992-01-01

    This thesis describes the successful development of ultra-high pressure proportional counters for balloon -borne hard X-ray astronomy. The proportional counters were filled with argon/xenon at pressures up to {~}30atm. The properties of proportional counters filled at such pressures have been studied by the author in the laboratory. The spatial response of these counters to X-rays and charged particles, and the energy response to X-rays up to 1MeV have been analysed. Gas gain measurements using the charge collection technique and analysis of the subsequent data show that simple extrapolation from low pressures cannot explain the observed behaviour (e.g. the mobility of positive ions and quenching efficiency) of these counters at high pressures. A hard X-ray telescope consisting of 32 such proportional counters filled at ultra-high pressures is being constructed, details of which are described. The sensitivity of this telescope for both continuum and narrow-line spectra is superb compared to contemporary balloon-and satellite-borne hard X-ray detectors. Together with an imaging phoswich Anger camera, it is scheduled for launch from Alice Springs in November 1992. An anticoincidence system for an X-ray detector, consisting of a combined passive and active shield, has been designed and constructed by the author, and flown on a balloon. The active shield, made of a plastic scintillator, has resulted in an additional reduction of 25% in the background registered at balloon altitudes.

  2. Fabrication of a focusing soft X-ray collector payload

    NASA Technical Reports Server (NTRS)

    Davis, J. M.; Decaprio, A. R.; Manko, H.; Ting, J. W. S.

    1976-01-01

    A large area X-ray focusing collector with arc minute resolution and a position sensitive detector capable of operating in the soft X-ray region was developed for use on sounding rockets in studying stellar X-ray sources. The focusing payload consists of the following components, which are described: (1) a crossed paraboloid mirror assembly; (2) an aspect camera and star tracker; (3) a focal plane assembly containing an imaging proportional counter and its preamplifiers, high voltage power supplies and gas system; (4) a fiducial system; and (5) housekeeping, data handling, instrumentation and telemetry electronics. The design, tests, and operation are described.

  3. A microstitching interferometer for evaluating the surface profile of precisely figured hard x-ray K-B mirrors.

    SciTech Connect

    Assoufid, L.; Qian, J.; Kewish, C. M.; Liu, C.; Conley, R.; Macrander, A. T.; Lindley, D.; Saxer, C.; X-Ray Science Division; KLA-Tencor

    2007-01-01

    Fabrication and evaluation of elliptical X-ray mirrors, such as Kirkpatrick-Baez (K-B) mirrors produced by the profile-coating technique, requires accurate surface figure measurements over a wide range of spatial frequencies. Microstitching interferometry has proven to fulfill this requirement for length scales from a few {micro}m up to the full mirror length. At the Advanced Photon Source, a state-of-the-art microroughness microscope interferometer that incorporates advanced microstitching capability has been used to obtain measurements of profile-coated elliptical K-B mirrors. The stitched surface height data provide previously unattainable resolution and reproducibility, which has facilitated the fabrication of ultrasmooth (< 1 nm rms residual height) profile-coated mirrors, whose hard X-ray focusing performance is expected to approach the diffraction limit. This paper describes the system capabilities and limitations. Results of measurements obtained with it will be discussed and compared with those obtained with the Long Trace Profiler.

  4. Multi-temperature analysis of hard X-ray spectra measured aboard the Prognoz 5 satellite

    NASA Astrophysics Data System (ADS)

    Sylwester, B.; Sylwester, J.; Jakimiec, J.; Valnicek, B.; Farnik, F.

    1983-01-01

    Following the method of multi-temperature analysis of hard X-ray spectra presented by B. Sylwester et al. (1981), in the present paper the authors analyse the hard X-ray radiation measured aboard the Prognoz 5 satellite by means of a Czechoslovak photometer. The analysis concerns the Feb. 11, 1977 flare event. Using the fluxes measured in 4 energy bands they have calculated the differential emission measure distributions for selected moments during the rise, maximum and decay phases of the flare development. The results of the analysis show that, in the case of the flare in question, the hard X-ray radiation from 6 to 60 keV could have been produced by purely thermal, multi-temperature plasma.

  5. Hard X-ray Imaging for Measuring Laser Absorption Spatial Profiles on the National Ignition Facility

    SciTech Connect

    Dewald, E L; Jones, O S; Landen, O L; Suter, L; Amendt, P; Turner, R E; Regan, S

    2006-04-25

    Hard x-ray (''Thin wall'') imaging will be employed on the National Ignition Facility (NIF) to spatially locate laser beam energy deposition regions on the hohlraum walls in indirect drive Inertial Confinement Fusion (ICF) experiments, relevant for ICF symmetry tuning. Based on time resolved imaging of the hard x-ray emission of the laser spots, this method will be used to infer hohlraum wall motion due to x-ray and laser ablation and any beam refraction caused by plasma density gradients. In optimizing this measurement, issues that have to be addressed are hard x-ray visibility during the entire ignition laser pulse with intensities ranging from 10{sup 13} to 10{sup 15} W/cm{sup 2}, as well as simultaneous visibility of the inner and the outer laser drive cones. In this work we will compare the hard x-ray emission calculated by LASNEX and analytical modeling with thin wall imaging data recorded previously on Omega and during the first hohlraum experiments on NIF. Based on these calculations and comparisons the thin wall imaging will be optimized for ICF/NIF experiments.

  6. Correlative analysis of hard and soft x ray observations of solar flares

    NASA Technical Reports Server (NTRS)

    Zarro, Dominic M.

    1994-01-01

    We have developed a promising new technique for jointly analyzing BATSE hard X-ray observations of solar flares with simultaneous soft X-ray observations. The technique is based upon a model in which electric currents and associated electric fields are responsible for the respective heating and particle acceleration that occur in solar flares. A useful by-product of this technique is the strength and evolution of the coronal electric field. The latter permits one to derive important flare parameters such as the current density, the number of current filaments composing the loop, and ultimately the hard X-ray spectrum produced by the runaway electrons. We are continuing to explore the technique by applying it to additional flares for which we have joint BATSE/Yohkoh observations. A central assumption of our analysis is the constant of proportionality alpha relating the hard X-ray flux above 50 keV and the rate of electron acceleration. For a thick-target model of hard X-ray production, it can be shown that cv is in fact related to the spectral index and low-energy cutoff of precipitating electrons. The next step in our analysis is to place observational constraints on the latter parameters using the joint BATSE/Yohkoh data.

  7. Great microwave bursts and hard X-rays from solar flares

    NASA Technical Reports Server (NTRS)

    Wiehl, H. J.; Batchelor, D. A.; Crannell, C. J.; Dennis, B. R.; Price, P. N.

    1983-01-01

    The microwave and hard X-ray charateristics of 13 solar flares that produced microwave fluxes greater than 500 Solar Flux Units were analyzed. These Great Microwave Bursts were observed in the frequency range from 3 to 35 GHz at Berne, and simultaneous hard X-ray observations were made in the energy range from 30 to 500 keV with the Hard X-Ray Burst Spectrometer on the Solar Maximum Mission spacecraft. The principal aim of this analysis is to determine whether or not the same distribution of energetic electrons can explain both emissions. Correlations were found between respective temporal characteristics and, for the first time, between microwave and hard X-ray spectral characteristics. A single-temperature and a multi-temperature model from the literature were tested for consistency with the coincident X-ray and microwave spectra at microwave burst maximum. Four events are inconsistent with both of the models tested, and neither of the models attempts to explain the high-frequency part of the microwave spectrum. A model in which the emissions above and below the peak frequency originate in two different parts of a diverging magnetic loop is proposed. With this model the entire microwave spectrum of all but one of the events is explained.

  8. An investigation of small goes flares with intense hard x-ray bursts

    NASA Astrophysics Data System (ADS)

    McDonald, L.; Harra-Murnion, L. K.; Culhane, J. L.; Schwartz, A.

    1997-01-01

    Most solar flare observations show that intense hard X-ray bursts come from large flares that have a large GOES classification (large peak 1 - 8 A˚ flux). This correlation, known as the ``Big Flare Syndrome'', suggests that more intense flares tend to have harder spectra. We have observed 7 flares that are exceptions to this. These flares have small GOES classifications ranging from B1.4 to C5.5 and peak hard X-ray count rates similar to those often observed from M class flares. This paper examines the cause of this anomoly using the Yohkoh Soft X-Ray Telescope, Hard X-Ray Telescope, and Bragg Crystal Spectrometer. Two hypotheses are proposed for the exceptions: (1) flares with multiple magnetic loops and common footpoints, producing multiple hard X-ray emission regions and low density thermal plasma distributed over a large volume, and (2) high densities in the magnetic loops restricting the propagation of the non-thermal electrons in the loop after magnetic reconnection has occurred and suppressing chromospheric evaporation. Two of the flares support the first hypothesis. The other flares either have data missing or are too small to be properly analysed by the Yohkoh instruments.

  9. Preface: The 5th International Workshop on X-ray Mirror Design, Fabrication, and Metrology.

    PubMed

    Assoufid, Lahsen; Goldberg, Kenneth; Yashchuk, Valeriy V

    2016-05-01

    Recent developments in synchrotron storage rings and free-electron laser-based x-ray sources with ever-increasing brightness and coherent flux have pushed x-ray optics requirements to new frontiers. This Special Topic gathers a set of articles derived from a subset of the key presentations of the International Workshop on X-ray Mirrors Fabrication (IWXM-2015) and Metrology held at Lawrence Berkley National Laboratory, Berkeley, California, USA, July 14-16, 2015. The workshop objective was to report on recent progress in x-ray synchrotron radiation mirrors fabrication as well as on new developments in related metrology tools and methods. PMID:27250367

  10. A hard X-ray view of the soft excess in AGN

    NASA Astrophysics Data System (ADS)

    Boissay, Rozenn; Ricci, Claudio; Paltani, Stéphane

    2016-04-01

    An excess of X-ray emission below 1 keV, called soft excess, is detected in a large fraction of Seyfert 1-1.5s. The origin of this feature remains debated, as several models have been suggested to explain it, including warm Comptonization and blurred ionized reflection. In order to constrain the origin of this component, we exploit the different behaviors of these models above 10 keV. Ionized reflection covers a broad energy range, from the soft X-rays to the hard X-rays, while Comptonization drops very quickly in the soft X-rays. We present here the results of a study done on 102 Seyfert 1s (Sy 1.0, 1.2, 1.5 and NLSy1) from the Swift BAT 70-Month Hard X-ray Survey catalog. The joint spectral analysis of Swift/BAT and XMM-Newton data allows a hard X-ray view of the soft excess that is present in about 80% of the objects of our sample. We discuss how the soft-excess strength is linked to the reflection at high energy, to the photon index of the primary continuum and to the Eddington ratio. In particular, we find a positive dependence of the soft excess intensity on the Eddington ratio. We compare our results to simulations of blurred ionized-reflection models and show that they are in contradiction. By stacking both XMM-Newton and Swift/BAT spectra per soft-excess strength, we see that the shape of reflection at hard X-rays stays constant when the soft excess varies, showing an absence of link between reflection and soft excess. We conclude that the ionized-reflection model as the origin of the soft excess is disadvantaged in favor of the warm Comptonization model in our sample of Seyfert 1s.

  11. The Hard X-Ray Spectrum of NGC 1365: Scattered Light, Not Black Hole Spin

    NASA Astrophysics Data System (ADS)

    Miller, L.; Turner, T. J.

    2013-08-01

    Active galactic nuclei (AGNs) show excess X-ray emission above 10 keV compared with extrapolation of spectra from lower energies. Risaliti et al. have recently attempted to model the hard X-ray excess in the type 1.8 AGN NGC 1365, concluding that the hard excess most likely arises from Compton-scattered reflection of X-rays from an inner accretion disk close to the black hole. Their analysis disfavored a model in which the hard excess arises from a high column density of circumnuclear gas partially covering a primary X-ray source, despite such components being required in the NGC 1365 data below 10 keV. Using a Monte Carlo radiative transfer approach, we demonstrate that this conclusion is invalidated by (1) use of slab absorption models, which have unrealistic transmission spectra for partial covering gas, (2) neglect of the effect of Compton scattering on transmitted spectra, and (3) inadequate modeling of the spectrum of scattered X-rays. The scattered spectrum is geometry-dependent and, for high global covering factors, may dominate above 10 keV. We further show that, in models of circumnuclear gas, the suppression of the observed hard X-ray flux by reprocessing may be no larger than required by the "light bending" model invoked for inner disk reflection, and the expected emission line strengths lie within the observed range. We conclude that the time-invariant "red wing" in AGN X-ray spectra is probably caused by continuum transmitted through and scattered from circumnuclear gas, not by highly redshifted line emission, and that measurement of black hole spin is not possible.

  12. THE HARD X-RAY SPECTRUM OF NGC 1365: SCATTERED LIGHT, NOT BLACK HOLE SPIN

    SciTech Connect

    Miller, L.; Turner, T. J.

    2013-08-10

    Active galactic nuclei (AGNs) show excess X-ray emission above 10 keV compared with extrapolation of spectra from lower energies. Risaliti et al. have recently attempted to model the hard X-ray excess in the type 1.8 AGN NGC 1365, concluding that the hard excess most likely arises from Compton-scattered reflection of X-rays from an inner accretion disk close to the black hole. Their analysis disfavored a model in which the hard excess arises from a high column density of circumnuclear gas partially covering a primary X-ray source, despite such components being required in the NGC 1365 data below 10 keV. Using a Monte Carlo radiative transfer approach, we demonstrate that this conclusion is invalidated by (1) use of slab absorption models, which have unrealistic transmission spectra for partial covering gas, (2) neglect of the effect of Compton scattering on transmitted spectra, and (3) inadequate modeling of the spectrum of scattered X-rays. The scattered spectrum is geometry-dependent and, for high global covering factors, may dominate above 10 keV. We further show that, in models of circumnuclear gas, the suppression of the observed hard X-ray flux by reprocessing may be no larger than required by the ''light bending'' model invoked for inner disk reflection, and the expected emission line strengths lie within the observed range. We conclude that the time-invariant ''red wing'' in AGN X-ray spectra is probably caused by continuum transmitted through and scattered from circumnuclear gas, not by highly redshifted line emission, and that measurement of black hole spin is not possible.

  13. Tracing the Reverberation Lag in the Hard State of Black Hole X-Ray Binaries

    NASA Astrophysics Data System (ADS)

    De Marco, B.; Ponti, G.; Muñoz-Darias, T.; Nandra, K.

    2015-11-01

    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.

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

    PubMed

    Perez, Kerstin; Hailey, Charles J; Bauer, Franz E; Krivonos, Roman A; Mori, Kaya; Baganoff, Frederick K; Barrière, Nicolas M; Boggs, Steven E; Christensen, Finn E; Craig, William W; Grefenstette, Brian W; Grindlay, Jonathan E; Harrison, Fiona A; Hong, Jaesub; Madsen, Kristin K; Nynka, Melania; Stern, Daniel; Tomsick, John A; Wik, Daniel R; Zhang, Shuo; Zhang, William W; Zoglauer, Andreas

    2015-04-30

    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 systems. Observations of diffuse hard-X-ray (more than 10 kiloelectronvolts) emission in the inner 10 parsecs, however, have been hampered by the limited spatial resolution of previous instruments. Here we report the presence of a distinct hard-X-ray component within the central 4 × 8 parsecs, as revealed by subarcminute-resolution images in the 20-40 kiloelectronvolt 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 outflows interacting with the surrounding radiation field, dense molecular material or magnetic fields. However, all these interpretations pose significant challenges to our understanding of stellar evolution, binary formation, and cosmic-ray production in the Galactic Centre. PMID:25925477

  15. Hard X-Ray Emission and the Ionizing Source in LINERs

    NASA Technical Reports Server (NTRS)

    Terashima, Y.; Ho, L. C.; Ptak, A. F.

    2004-01-01

    We report X-ray luminosities of 21 LINERs (low-ionization nuclear emission-line regions) and 17 low-luminosity Seyferts obtained with ASCA and discuss the ionizing source in LINERs. Most LINERs with broad H-alpha emission in their optical spectra (LINER 1s) have a compact hard X-ray source and their 2-10 keV X-ray luminosities (LX) are proportional to their H alpha luminosities (L-H-alpha). This correlation strongly supports the hypothesis that the dominant ionizing source in LINER 1s is photoionization by hard photons from low-luminosity AGNs. Although some LINERs without broad H-alpha emission (LINER 2s) have X-ray properties similar to LINER 1s, the X-ray luminosities of many LINER 2s in our sample are lower than LINER 1s at a given H-alpha luminosity. The observed X-ray luminosities in these objects are insufficient to power their H-alpha luminosities, suggesting that their primary ionizing source is something other than an AGN, or that an AGN, if present, is obscured even at energies above 2 keV. LINER 2s having small LX/LH-alpha occupy a localized region with small [OI]/H-alpha on the excitation diagram. Such LINER spectra can be reproduced by photoionization by very hot stars.

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

    NASA Astrophysics Data System (ADS)

    Perez, Kerstin; Hailey, Charles J.; Bauer, Franz E.; Krivonos, Roman A.; Mori, Kaya; Baganoff, Frederick K.; Barrière, Nicolas M.; Boggs, Steven E.; Christensen, Finn E.; Craig, William W.; Grefenstette, Brian W.; Grindlay, Jonathan E.; Harrison, Fiona A.; Hong, Jaesub; Madsen, Kristin K.; Nynka, Melania; Stern, Daniel; Tomsick, John A.; Wik, Daniel R.; Zhang, Shuo; Zhang, William W.; Zoglauer, Andreas

    2015-04-01

    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 systems. Observations of diffuse hard-X-ray (more than 10 kiloelectronvolts) emission in the inner 10 parsecs, however, have been hampered by the limited spatial resolution of previous instruments. Here we report the presence of a distinct hard-X-ray component within the central 4 × 8 parsecs, as revealed by subarcminute-resolution images in the 20-40 kiloelectronvolt 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 outflows interacting with the surrounding radiation field, dense molecular material or magnetic fields. However, all these interpretations pose significant challenges to our understanding of stellar evolution, binary formation, and cosmic-ray production in the Galactic Centre.

  17. HX-POL-A Balloon-Borne Hard X-Ray Polarimeter

    NASA Technical Reports Server (NTRS)

    Krawczynski, H.; Garson, A., III; Martin, J.; Li, Q.; Beilicke, M.; Dowkontt, P.; Lee, K.; Wulf, E.; Kurfess, J.; Novikova, E. I.; De Geronimo, G.; Baring, M. G.; Harding, A. K.; Grindlay, J.; Hong, J. S.

    2009-01-01

    We report on the design and estimated performance of a balloon-borne hard X-ray polarimeter called HX-POL. The experiment uses a combination of Si and Cadmium Zinc Telluride detectors to measure the polarization of 50 keV-400 keV X-rays from cosmic sources through the dependence of the angular distribution of Compton scattered photons on the polarization direction. On a one-day balloon flight, HX-POL would allow us to measure the polarization of bright Crab-like sources for polarization degrees well below 10%. On a longer (15-30 day) flight from Australia or Antarctica, HX-POL would be be able to measure the polarization of bright galactic X-ray sources down to polarization degrees of a few percent. Hard X-ray polarization measurements provide unique venues for the study of particle acceleration processes by compact objects and relativistic outflows. In this paper, we discuss the overall instrument design and performance. Furthermore, we present results from laboratory tests of the Si and CZT detectors. Index Terms Gamma-ray astronomy, gamma-ray astronomy detectors, polarization, semiconductor radiation detectors, X-ray astronomy, X-ray astronomy detectors.

  18. Systematic and Performance Tests of the Hard X-ray Polarimeter X-Calibur

    NASA Astrophysics Data System (ADS)

    Endsley, Ryan; Beilicke, Matthias; Kislat, Fabian; Krawczynski, Henric; X-Calibur/InFOCuS

    2015-01-01

    X-ray polarimetry has great potential to reveal new astrophysical information about the emission processes of high energy sources such as black hole environments, X-ray binary systems, and active galactic nuclei. Here we present the results and conclusions of systematic and performance measurements of the hard X-ray polarimeter, X-Calibur. Designed to be flown on a balloon-borne X-ray telescope, X-Calibur will achieve unprecedented sensitivity and makes use of the fact that polarized X-rays preferentially Compton-scatter perpendicular to their E-field vector. Extensive laboratory measurements taken at Washington University and the Cornell High-Energy Synchrotron Source (CHESS) indicate that X-Calibur combines a detection efficiency on the order of unity with a high modulation factor of µ ≈ 0.5 averaged over the whole detector assembly, and with values up to µ ≈ 0.7 for select subsections of the polarimeter. Additionally, we are able to suppress background flux by more than two orders of magnitude by utilizing an active shield and scintillator coincidence. Comparing laboratory data with Monte Carlo simulations of both polarized and unpolarized hard X-ray beams illustrate that we have an exceptional understanding of the detector response.

  19. Hard X-ray spatial array diagnostics on Joint Texas Experimental Tokamak

    SciTech Connect

    Huang, D. W.; Chen, Z. Y. Luo, Y. H.; Tong, R. H.; Yan, W.; Jin, W.; Zhuang, G.

    2014-11-15

    A spatially distributed hard X-ray detection array has been developed to diagnose the loss of runaway electron with toroidal and poloidal resolution. The hard X-ray radiation in the energy ranges of 0.3–1 MeV resulted from runaway electrons can be measured. The detection array consists of 12 CdTe detectors which are arranged surrounding the tokamak. It is found that most runaway electrons which transport to plasma boundary tend to loss on limiters. The application of electrode biasing probe resulted in enhancement of local runaway loss. Resonant magnetic perturbations enhanced the runaway electrons diffusion and showed an asymmetric poloidal loss rate.

  20. Pulse energy measurement at the hard x-ray laser in Japan

    SciTech Connect

    Kato, M.; Tanaka, T.; Saito, N.; Kurosawa, T.; Richter, M.; Sorokin, A. A.; Tiedtke, K.; Kudo, T.; Yabashi, M.; Tono, K.; Ishikawa, T.

    2012-07-09

    The pulse energies of a free electron laser have accurately been measured in the hard x-ray spectral range. In the photon energy regime from 4.4 keV to 16.8 keV, pulse energies up to 100 {mu}J were obtained at the hard x-ray laser facility SACLA (SPring-8 Angstrom Compact free-electron LAser). Two independent methods, using a cryogenic radiometer and a gas monitor detector, were applied and agreement within 3.3% was achieved. Based on our validated pulse energy measurement, a SACLA online monitor detector could be calibrated for all future experiments.

  1. Full-field hard x-ray microscopy with interdigitated silicon lenses

    NASA Astrophysics Data System (ADS)

    Simons, Hugh; Stöhr, Frederik; Michael-Lindhard, Jonas; Jensen, Flemming; Hansen, Ole; Detlefs, Carsten; Poulsen, Henning Friis

    2016-01-01

    Full-field x-ray microscopy using x-ray objectives has become a mainstay of the biological and materials sciences. However, the inefficiency of existing objectives at x-ray energies above 15 keV has limited the technique to weakly absorbing or two-dimensional (2D) samples. Here, we show that significant gains in numerical aperture and spatial resolution may be possible at hard x-ray energies by using silicon-based optics comprising 'interdigitated' refractive silicon lenslets that alternate their focus between the horizontal and vertical directions. By capitalizing on the nano-manufacturing processes available to silicon, we show that it is possible to overcome the inherent inefficiencies of silicon-based optics and interdigitated geometries. As a proof-of-concept of Si-based interdigitated objectives, we demonstrate a prototype interdigitated lens with a resolution of ≈255 nm at 17 keV.

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

    PubMed

    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. PMID:25971656

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

    PubMed Central

    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. PMID:25971656

  4. X-ray phase imaging using a Gd-based absorption grating fabricated by imprinting technique

    NASA Astrophysics Data System (ADS)

    Yashiro, Wataru; Kato, Kosuke; Sadeghilaridjani, Maryam; Momose, Atsushi; Shinohara, Takenao; Kato, Hidemi

    2016-04-01

    A high-aspect-ratio absorption grating with a pitch of several µm is a key component of X-ray grating interferometery, which is an X-ray phase imaging technique that allows for highly sensitive X-ray imaging with a compact laboratory X-ray source. Here, we report that X-ray phase imaging was successfully performed at 15 keV by using a 23 ± 1-µm-height, 9-µm-pitch absorption grating (10 × 10 mm2) based on Gd (Gd60Cu25Al15) fabricated by a metallic glass imprinting technique. The imprinting technique is cost-efficient and has a high-production rate, and will be widely used for fabricating gratings not only for X-rays but also neutrons in the near future.

  5. A comparison of the height distributions of solar flare hard X-rays in thick target and thermal models

    NASA Technical Reports Server (NTRS)

    Emslie, A. G.

    1980-01-01

    The height structure of hard X-ray bremsstrahlung emission in solar flares is computed for two different models of bremsstrahlung production: emission from a descending beam of nonthermal electrons, and thermal emission from a coronally confined hot plasma. It is shown how these models give rise to hard X-ray spatial distributions which are distinguishable by current instrumentation, and that, therefore, the models may be distinguished by such spatially resolved hard X-ray measurements.

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

    SciTech Connect

    Chakrabarty, Deepto; Nowak, Michael A.; Tomsick, John A.; Boggs, Steven E.; Craig, William W.; Grefenstette, Brian W.; Fürst, Felix; Harrison, Fiona A.; Rana, Vikram; Psaltis, Dimitrios; Bachetti, Matteo; Barret, Didier; Christensen, Finn E.; Hailey, Charles J.; Kaspi, Victoria M.; Miller, Jon M.; Stern, Daniel; Wik, Daniel R.; Zhang, William W.; Wilms, Jörn

    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.

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

    NASA Astrophysics Data System (ADS)

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

    2014-05-01

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

  8. Mitigation of hard x-ray background in backlit pinhole radiography

    NASA Astrophysics Data System (ADS)

    Fein, Jeffrey; Keiter, Paul; Holloway, James P.; Davis, Joshua; Klein, Sallee; Kuranz, Carolyn; Drake, R. Paul; CLEAR Team

    2014-10-01

    Backlit pinhole imaging is a technique commonly used to image plasmas in high-energy-density physics experiments with sub-10 micron spatial resolution and sub-nanosecond time resolution. Lasers heat a mid-Z foil, which emits He α x-rays that attenuate through the object and produce a radiograph on an x-ray detector. Radiographic data has consistently shown an underlying background signal, decreasing the signal dynamic range and increasing noise. Past experiments demonstrated that a hard x-ray background results from hot electrons generated at the laser spot interacting with the high-Z pinhole substrate. We propose that the majority of the hot electrons are produced in the plastic scaffold holding the foil, via the two-plasmon decay instability. It is expected that increasing the material Z of the scaffold will mitigate production of hot electrons, and hence, the hard x-ray background produced in the pinhole substrate. We will present experimental results from the OMEGA laser, testing this hypothesis, where Al and V scaffolds are compared to traditional plastic. Hard x-ray background and resolution characteristics from radiographs will be compared between the different materials. This work was funded by the NNSA-DS and SC-OFES Joint Program in HED Laboratory Plasmas, Grant Number DE-NA0001840, the NLUF Program, Grant Number DE-NA0000850, by the DTRA, Grant Number DTRA-1-10-0077 and by the NSF GRFP.

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

    SciTech Connect

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

    2014-05-15

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

  10. Hard X-ray Detectability of Small Impulsive Heating Events in the Solar Corona

    NASA Astrophysics Data System (ADS)

    Glesener, L.; Klimchuk, J. A.; Bradshaw, S. J.; Marsh, A.; Krucker, S.; Christe, S.

    2015-12-01

    Impulsive heating events ("nanoflares") are a candidate to supply the solar corona with its ~2 MK temperature. These transient events can be studied using extreme ultraviolet and soft X-ray observations, among others. However, the impulsive events may occur in tenuous loops on small enough timescales that the heating is essentially not observed due to ionization timescales, and only the cooling phase is observed. Bremsstrahlung hard X-rays could serve as a more direct and prompt indicator of transient heating events. A hard X-ray spacecraft based on the direct-focusing technology pioneered by the Focusing Optics X-ray Solar Imager (FOXSI) sounding rocket could search for these direct signatures. In this work, we use the hydrodynamical EBTEL code to simulate differential emission measures produced by individual heating events and by ensembles of such events. We then directly predict hard X-ray spectra and consider their observability by a future spaceborne FOXSI, and also by the RHESSI and NuSTAR spacecraft.

  11. High spectral resolution measurements of a solar flare hard X-ray burst

    NASA Technical Reports Server (NTRS)

    Lin, R. P.; Schwartz, R. A.

    1987-01-01

    Observations are reported of an intense solar flare hard X-ray burst on June 27, 1980, made with a balloon-borne array of liquid nitrogen-cooled Ge detector which provided unprecedented spectral resolution (no more than 1 keV FWHM). The hard X-ray spectra throughout the impulsive phase burst fitted well to a double power-law form, and emission from an isothermal 0.1-1 billion K plasma can be specifically excluded. The temporal variations of the spectrum indicate that the hard X-ray burst is made up of two superposed components: individual spikes lasting about 3-15 sec, which have a hard spectrum and a break energy of 30-65 keV; and a slowly varying component characterized by a soft spectrum with a constant low-energy slope and a break energy which increases from 25 kev to at least 100 keV through the event. The double power-law shape indicates that DC electric field acceleration, similar to that occurring in the earth's auroral zone, may be the source of the energetic electrons which produce the hard X-ray emission.

  12. Hard X-Ray Flares Preceding Soft X-Ray Outbursts in Aquila X-1: A Link between Neutron Star and Black Hole State Transitions

    NASA Astrophysics Data System (ADS)

    Yu, Wenfei; Klein-Wolt, Marc; Fender, Rob; van der Klis, Michiel

    2003-05-01

    We have analyzed Rossi X-Ray Timing Explorer data of the neutron star transient Aquila X-1 obtained during its outbursts in 1999 May/June and 2000 September/October. We find that in the early rise of these outbursts, a hard flare in the energy range above 15 keV preceded the soft X-ray peak. The hard X-ray flux of the hard flares at maximum was more than a factor of 3 stronger than at any other point in the outbursts. The rise of the hard X-ray flare to this maximum was consistent with a monotonically brightening low-/hard-state spectrum. After the peak of the hard flare, a sharp spectral transition occurred with spectral pivoting in the range 8-12 keV. Our timing analysis shows that during the hard flare, the power spectra were composed mainly of band-limited noise and a ~1-20 Hz quasi-periodic oscillation (QPO), which correlate in frequency. Immediately after the hard flare, the power spectra turned into power-law noise. The spectral and timing properties during and after the hard flares are very similar to those in black hole transients during the early rise of an outburst. We suggest that these hard flares and spectral transitions in Aql X-1 are of the same origin as those observed in black hole transients. This leads to the association of the 1-20 Hz QPOs and band-limited noise in Aql X-1 with those in black hole transients. We discuss the impact of this discovery on our understanding of soft X-ray transient outbursts, state transitions, and variability in X-ray binaries.

  13. Multimodality hard-x-ray imaging of a chromosome with nanoscale spatial resolution

    DOE PAGESBeta

    Yan, Hanfei; Nazaretski, Evgeny; Lauer, Kenneth R.; Huang, Xiaojing; Wagner, Ulrich; Rau, Christoph; Yusuf, Mohammed; Robinson, Ian K.; Kalbfleisch, Sebastian; Li, Li; et al

    2016-02-05

    Here, we developed a scanning hard x-ray microscope using a new class of x-ray nano-focusing optic called a multilayer Laue lens and imaged a chromosome with nanoscale spatial resolution. The combination of the hard x-ray's superior penetration power, high sensitivity to elemental composition, high spatial-resolution and quantitative analysis creates a unique tool with capabilities that other microscopy techniques cannot provide. Using this microscope, we simultaneously obtained absorption-, phase-, and fluorescence-contrast images of Pt-stained human chromosome samples. The high spatial-resolution of the microscope and its multi-modality imaging capabilities enabled us to observe the internal ultra-structures of a thick chromosome without sectioningmore » it.« less

  14. Hard X-ray Detectability of Small-Scale Coronal Heating Events

    NASA Astrophysics Data System (ADS)

    Marsh, Andrew; Glesener, Lindsay; Klimchuk, James A.; Bradshaw, Stephen; Smith, David; Hannah, Iain

    2016-05-01

    The nanoflare heating theory predicts the ubiquitous presence of hot (~>5 MK) plasma in the solar corona, but evidence for this high-temperature component has been scarce. Current hard x-ray instruments such as RHESSI lack the sensitivity to see the trace amounts of this plasma that are predicted by theoretical models. New hard X-ray instruments that use focusing optics, such as FOXSI (the Focusing Optics X-ray Solar Imager) and NuSTAR (the Nuclear Spectroscopic Telescope Array) can extend the visible parameter space of nanoflare “storms” that create hot plasma. We compare active-region data from FOXSI and NuSTAR with a series of EBTEL hydrodynamic simulations, and constrain nanoflare properties to give good agreement with observations.

  15. Hard-X-ray magnetic microscopy and local magnetization analysis using synchrotron radiation.

    PubMed

    Suzuki, Motohiro

    2014-11-01

    X-ray measurement offers several useful features that are unavailable from other microscopic means including electron-based techniques. By using X-rays, one can observe the internal parts of a thick sample. This technique basically requires no high vacuum environment such that measurements are feasible for wet specimens as well as under strong electric and magnetic fields and even at a high pressure. X-ray spectroscopy using core excitation provides element-selectivity with significant sensitivities to the chemical states and atomic magnetic moments in the matter. Synchrotron radiation sources produce a small and low-divergent X-ray beam, which can be converged to a spot with the size of a micrometer or less using X-ray focusing optics. The recent development in the focusing optics has been driving X-ray microscopy, which has already gone into the era of X-ray nanoscopy. With the use of the most sophisticated focusing devices, an X-ray beam of 7-nm size has successfully been achieved [1]. X-ray microscopy maintains above-mentioned unique features of X-ray technique, being a perfect complement to electron microscopy.In this paper, we present recent studies on magnetic microscopy and local magnetic analysis using hard X-rays. The relevant instrumentation developments are also described. The X-ray nanospectroscopy station of BL39XU at SPring-8 is equipped with a focusing optics consisting of two elliptic mirrors, and a focused X-ray beam with the size of 100 × 100 nm(2) is available [2]. Researchers can perform X-ray absorption spectroscopy: nano-XAFS (X-ray absorption fine structure) using the X-ray beam as small as 100 nm. The available X-ray energy is from 5 to 16 keV, which allows nano-XAFS study at the K edges of 3d transition metals, L edges of rare-earth elements and 5d noble metals. Another useful capability of the nanoprobe is X-ray polarization tunability, enabling magnetic circular dichroism (XMCD) spectroscopy with a sub-micrometer resolution. Scanning

  16. Enhancing Tabletop X-Ray Phase Contrast Imaging with Nano-Fabrication

    NASA Astrophysics Data System (ADS)

    Miao, Houxun; Gomella, Andrew A.; Harmon, Katherine J.; Bennett, Eric E.; Chedid, Nicholas; Znati, Sami; Panna, Alireza; Foster, Barbara A.; Bhandarkar, Priya; Wen, Han

    2015-08-01

    X-ray phase-contrast imaging is a promising approach for improving soft-tissue contrast and lowering radiation dose in biomedical applications. While current tabletop imaging systems adapt to common x-ray tubes and large-area detectors by employing absorptive elements such as absorption gratings or monolithic crystals to filter the beam, we developed nanometric phase gratings which enable tabletop x-ray far-field interferometry with only phase-shifting elements, leading to a substantial enhancement in the performance of phase contrast imaging. In a general sense the method transfers the demands on the spatial coherence of the x-ray source and the detector resolution to the feature size of x-ray phase masks. We demonstrate its capabilities in hard x-ray imaging experiments at a fraction of clinical dose levels and present comparisons with the existing Talbot-Lau interferometer and with conventional digital radiography.

  17. Enhancing Tabletop X-Ray Phase Contrast Imaging with Nano-Fabrication.

    PubMed

    Miao, Houxun; Gomella, Andrew A; Harmon, Katherine J; Bennett, Eric E; Chedid, Nicholas; Znati, Sami; Panna, Alireza; Foster, Barbara A; Bhandarkar, Priya; Wen, Han

    2015-01-01

    X-ray phase-contrast imaging is a promising approach for improving soft-tissue contrast and lowering radiation dose in biomedical applications. While current tabletop imaging systems adapt to common x-ray tubes and large-area detectors by employing absorptive elements such as absorption gratings or monolithic crystals to filter the beam, we developed nanometric phase gratings which enable tabletop x-ray far-field interferometry with only phase-shifting elements, leading to a substantial enhancement in the performance of phase contrast imaging. In a general sense the method transfers the demands on the spatial coherence of the x-ray source and the detector resolution to the feature size of x-ray phase masks. We demonstrate its capabilities in hard x-ray imaging experiments at a fraction of clinical dose levels and present comparisons with the existing Talbot-Lau interferometer and with conventional digital radiography. PMID:26315891

  18. Enhancing Tabletop X-Ray Phase Contrast Imaging with Nano-Fabrication

    PubMed Central

    Miao, Houxun; Gomella, Andrew A.; Harmon, Katherine J.; Bennett, Eric E.; Chedid, Nicholas; Znati, Sami; Panna, Alireza; Foster, Barbara A.; Bhandarkar, Priya; Wen, Han

    2015-01-01

    X-ray phase-contrast imaging is a promising approach for improving soft-tissue contrast and lowering radiation dose in biomedical applications. While current tabletop imaging systems adapt to common x-ray tubes and large-area detectors by employing absorptive elements such as absorption gratings or monolithic crystals to filter the beam, we developed nanometric phase gratings which enable tabletop x-ray far-field interferometry with only phase-shifting elements, leading to a substantial enhancement in the performance of phase contrast imaging. In a general sense the method transfers the demands on the spatial coherence of the x-ray source and the detector resolution to the feature size of x-ray phase masks. We demonstrate its capabilities in hard x-ray imaging experiments at a fraction of clinical dose levels and present comparisons with the existing Talbot-Lau interferometer and with conventional digital radiography. PMID:26315891

  19. Peculiar nature of hard X-ray eclipse in SS433 from INTEGRAL observations

    NASA Astrophysics Data System (ADS)

    Cherepashchuk, A. M.; Sunyaev, R. A.; Postnov, K. A.; Antokhina, E. A.; Molkov, S. V.

    2009-07-01

    The analysis of hard X-ray INTEGRAL observations (2003-2008) of superaccreting Galactic microquasar SS433 at precessional phases of the source with the maximum disc opening angle is carried out. It is found that the shape and width of the primary X-ray eclipse are strongly variable, suggesting additional absorption in dense stellar wind and gas outflows from the optical A7I component and the wind-wind collision region. The independence of the observed hard X-ray spectrum on the accretion disc precessional phase suggests that hard X-ray emission (20-100 keV) is formed in an extended, hot, quasi-isothermal corona, probably heated by interaction of relativistic jet with inhomogeneous wind outflow from the precessing supercritical accretion disc. A joint modelling of X-ray eclipsing and precessional hard X-ray variability of SS433 revealed by INTEGRAL by a geometrical model suggests the binary mass ratio q = mx/mv ~= 0.25-0.5. The absolute minimum of joint orbital and precessional χ2 residuals is reached at q ~= 0.3. The found binary mass ratio range allows us to explain the substantial precessional variability of the minimum brightness at the middle of the primary optical eclipse. For the mass function of the optical star fv = 0.268Msolar as derived from Hillwig & Gies data, the obtained value of q ~= 0.3 yields the masses of the components mx ~= 5.3Msolar, mv ~= 17.7Msolar, confirming the black hole nature of the compact object in SS433.

  20. The Relationship Between Solar Radio and Hard X-Ray Emission

    NASA Technical Reports Server (NTRS)

    White, S. M.; Benz, A. O.; Christe, S.; Farnik, F.; Kundu, M. R.; Mann, G.; Ning, Z.; Raulin, J.-P.; Silva-Valio, A. V. R.; Saint-Hilaire, P.; Vilmer, N.; Warmuth, A.

    2011-01-01

    This review discusses the complementary relationship between radio and hard Xray observations of the Sun using primarily results from the era of the Reuven Ramaty High Energy Solar Spectroscopic Imager satellite. A primary focus of joint radio and hard X-ray studies of solar flares uses observations of nonthermal gyrosynchrotron emission at radio wavelengths and bremsstrahlung hard X-rays to study the properties of electrons accelerated in the main flare site, since it is well established that these two emissions show very similar temporal behavior. A quantitative prescription is given for comparing the electron energy distributions derived separately from the two wavelength ranges: this is an important application with the potential for measuring the magnetic field strength in the flaring region, and reveals significant differences between the electrons in different energy ranges. Examples of the use of simultaneous data from the two wavelength ranges to derive physical conditions are then discussed, including the case of microflares, and the comparison of images at radio and hard X-ray wavelengths is presented. There have been puzzling results obtained from observations of solar flares at millimeter and submillimeter wavelengths, and the comparison of these results with corresponding hard X-ray data is presented. Finally, the review discusses the association of hard X-ray releases with radio emission at decimeter and meter wavelengths, which is dominated by plasma emission (at lower frequencies) and electron cyclotron maser emission (at higher frequencies), both coherent emission mechanisms that require small numbers of energetic electrons. These comparisons show broad general associations but detailed correspondence remains more elusive.

  1. Efficient high-resolution hard x-ray imaging with transparent Lu2O3:Eu scintillator thin films

    NASA Astrophysics Data System (ADS)

    Marton, Zsolt; Miller, Stuart R.; Brecher, Charles; Kenesei, Peter; Moore, Matthew D.; Woods, Russell; Almer, Jonathan D.; Miceli, Antonino; Nagarkar, Vivek V.

    2015-09-01

    We have developed microstructured Lu2O3:Eu scintillator films that provide spatial resolution on the order of micrometers for hard X-ray imaging. In addition to their outstanding resolution, Lu2O3:Eu films also exhibits both high absorption efficiency for 20 to 100 keV X-rays, and bright 610 nm emission whose intensity rivals that of the brightest known scintillators. At present, high spatial resolution of such a magnitude is achieved using ultra-thin scintillators measuring only about 1 to 5 μm in thickness, which limits absorption efficiency to ~3% for 12 keV X-rays and less than 0.1% for 20 to 100 keV X-rays; this results in excessive measurement time and exposure to the specimen. But the absorption efficiency of Lu2O3:Eu (99.9% @12 keV and 30% @ 70 keV) is much greater, significantly decreasing measurement time and radiation exposure. Our Lu2O3:Eu scintillator material, fabricated by our electron-beam physical vapor deposition (EB-PVD) process, combines superior density of 9.5 g/cm3, a microcolumnar structure for higher spatial resolution, and a bright emission (48000 photons/MeV) whose wavelength is an ideal match for the underlying CCD detector array. We grew thin films of this material on a variety of matching substrates, measuring some 5-10μm in thickness and covering areas up to 1 x 1 cm2, which can be a suitable basis for microtomography, digital radiography as well as CT and hard X-ray Micro-Tomography (XMT). The microstructure and optical transparency of such screens was optimized, and their imaging performance was evaluated in the Argonne National Laboratory's Advanced Photon Source. Spatial resolution and efficiency were also characterized.

  2. High efficiency microcolumnar Lu2O3:Eu scintillator thin film for hard X-ray microtomography

    NASA Astrophysics Data System (ADS)

    Marton, Z.; Bhandari, H. B.; Brecher, C.; Miller, S. R.; Singh, B.; Nagarkar, V. V.

    2013-03-01

    We have developed microstructured Lu2O3:Eu scintillator films capable of providing spatial resolution on the order of micrometers for hard X-ray imaging. In addition to their extraordinary resolution, Lu2O3:Eu films simultaneously provide high absorption efficiency for 20 to 100 keV X-rays, and bright 610 nm emission, with intensity rivalling that of the brightest known scintillators. At present, high spatial resolution of such a magnitude is achieved using ultra-thin scintillators measuring only about 1 to 5 μm in thickness, which limits absorption efficiency to ~3% for 12 keV X-rays and less than 0.1% for 20 to 100 keV X-rays, resulting in excessive measurement time and exposure to the specimen. Lu2O3:Eu would significantly improve that (99.9% @12 keV and 30% @ 70 keV). Important properties and features of our Lu2O3:Eu scintillator material, fabricated by our electron-beam physical vapour deposition (EB-PVD) process, combines superior density of 9.5 g/cm3, microcolumnar structure emitting 48000 photons/MeV whose wavelength is an ideal match for the underlying CCD detector array. We grew thin films measuring 5-50μm in thickness as well as covering areas up to 5 × 5 cm2 which can be a suitable basis for microtomography, digital radiography as well as CT and hard X-ray Micro-Tomography (XMT).

  3. Femtosecond optical/hard X-ray timing diagnostics at an FEL: implementation and performance

    NASA Astrophysics Data System (ADS)

    Lemke, Henrik T.; Weaver, Matt; Chollet, Matthieu; Robinson, Joseph; Glownia, James M.; Zhu, Diling; Bionta, Mina R.; Cammarata, Marco; Harmand, Marion; Coffee, Ryan N.; Fritz, David M.

    2013-05-01

    The development of Free Electron Lasers has opened the possibility to investigate ultrafast processes using femtosecond hard x-ray pulses. In optical/x-ray light pump/probe experiments, however, the time resolution is mainly limited by the ability to synchronize both light sources over a long distance (<100 fs FWHM) rather than their pulse length (<10 fs FWHM). We have implemented a spectrally encoding x-ray to optical laser timing diagnostic into the XPP beamline at LCLS with a timing uncertainty down to 10 fs. An x-ray induced change of refractive index in a solid target is temporally probed for single pulses by a chirped white light pulse [4]. By resorting single shot data to the timestamps obtained by the diagnostics, the temporal data quality can be improved to basically pulse length limited time resolution. By interchangable targets and adjustable x-ray and laser foci, the method was successfully applied for very different x-ray parameters. These are different photon energies in the range of 6-20 keV, which at LCLS also includes application of 3rd Harmonic radiation, pulse energy, and bandwidth, when using a Si(111) monochromator.

  4. A Focused, Hard X-Ray Look at Arp 299 with NuSTAR

    NASA Astrophysics Data System (ADS)

    Ptak, A.; Hornschemeier, A.; Zezas, A.; Lehmer, B.; Yukita, M.; Wik, D.; Antoniou, V.; Argo, M. K.; Ballo, L.; Bechtol, K.; Boggs, S.; Della Ceca, R.; Christensen, F. E.; Craig, W. W.; Hailey, C. J.; Harrison, F. A.; Krivonos, R.; Maccarone, T. J.; Stern, D.; Tatum, M.; Venters, T.; Zhang, W. W.

    2015-02-01

    We report on simultaneous observations of the local starburst system Arp 299 with NuSTAR and Chandra, which provides the first resolved images of this galaxy up to energies of ~45 keV. Fitting the 3-40 keV spectrum reveals a column density of N H ~ 4 × 1024 cm-2, characteristic of a Compton-thick active galactic nucleus (AGN), and a 10-30 keV luminosity of 1.2 × 1043 erg s-1. The hard X-rays detected by NuSTAR above 10 keV are centered on the western nucleus, Arp 299-B, which previous X-ray observations have shown to be the primary source of neutral Fe-K emission. Other X-ray sources, including Arp 299-A, the eastern nucleus also thought to harbor an AGN, as well as X-ray binaries, contribute <~ 10% to the 10-20 keV emission from the Arp 299 system. The lack of significant emission above 10 keV other than that attributed to Arp 299-B suggests that: (1) any AGN in Arp 299-A must be heavily obscured (N H > 1024 cm-2) or have a much lower luminosity than Arp 299-B and (2) the extranuclear X-ray binaries have spectra that cut-off above ~10 keV. Such soft spectra are characteristic of ultraluminous X-ray sources observed to date by NuSTAR.

  5. Hard X-ray imaging facility for space shuttle: A scientific and conceptual engineering study

    NASA Technical Reports Server (NTRS)

    Peterson, L. E.; Hudson, H. S.; Hurford, G.; Schneible, D.

    1976-01-01

    A shuttle-accommodated instrument for imaging hard X-rays in the study of nonthermal particles and high temperature particles in various solar and cosmic phenomena was defined and its feasibility demonstrated. The imaging system configuration is described as well as the electronics, aspect systems, mechanical and thermal properties and the ground support equipment.

  6. Theoretical motivation for high spatial resolution, hard X-ray observations during solar flares

    NASA Technical Reports Server (NTRS)

    Emslie, A. G.

    1986-01-01

    The important role played by hard X-ray radiation as a diagnostic of impulsive phase energy transport mechanism is reviewed. It is argued that the sub-arc second resolution offered by an instrument such as the Pinhole/Occulter Facility (P/OF) can greatly increase our understanding of such mechanisms.

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

    NASA Astrophysics Data System (ADS)

    Shevelev, A.; Kiptily, V.; Chugunov, I.; Khilkevitch, E.; Gin, D.; Doinikov, D.; Naidenov, V.; Plyusnin, V.; EFDA-JET contributors

    2014-08-01

    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.

  8. The Hard X-ray Emission from Scorpius X-1 as Seen by INTEGRAL

    NASA Technical Reports Server (NTRS)

    Sturner, S. J.; Shrader, C. R.; Weidenspointner, G.

    2008-01-01

    We present the results of our hard X-ray and gamma-ray study of the LMXB Sco X-1 utilizing INTEGRAL data as well as contemporaneous RXTE PCA data. We have concentrated on investigating the hard X-ray spectral properties of Sco X-1 including the nature of the high-energy, nonthermal component of the spectrum and its possible correlations with the location of the source on the X-ray color-color diagram. We find that Sco X-1 has two distinct spectral when the 20-40 keV count rate is greater than 140 counts/second. One state is a hard state which exhibits a significant high-energy, powerlaw tail to the lower energy thermal spectrum. The other state shows no evidence for a powerlaw tail whatsoever. We found suggestive evidence for a correlation of these hard and soft high-energy states with the position of Sco X-1 on the low-energy X-ray color-color diagram.

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

    SciTech Connect

    Shevelev, A.; Chugunov, I.; Khilkevitch, E.; Gin, D.; Doinikov, D.; Naidenov, V.; Kiptily, V.; 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.

  10. Hard X-ray imaging of Cyg X-1 using balloon borne Fresnel Zone plates imager

    NASA Astrophysics Data System (ADS)

    Manchanda, R. K.

    Imaging in hard X-rays above 20 keV is a well known technological challenge. Coded aperture mask have been used in the past, but these require position sensitive detectors. However, the scintillation counters which form the bulk of hard X-ray detectors as these offer high detection efficiency, do not have intrinsic position sensitivity. Pixilated solid state detectors CZT and CdTe are being developed as the detectors for imaging telescope with coded mask. Alternatively, a combination of Fresnel Zone Plates (FZP) can also be used for imaging in the hard X-ray band. We have developed a new imaging telescope using a pair of tungsten FZP and tiny hard X-ray imager, made with thin NaI(Tl) viewed by a position sensitive photomultiplier. The instrument was launched as a piggyback on the Large Area Scintillation counter Experiment (LASE) in a balloon flight conducted on April 25, 2008 and reached a ceiling altitude 2.8 mb. Cyg X-1, was observed during the flight to study the imaging efficacy of FZP imager. This paper describes the details of the experiment, digital reconstruction of the imaged data.

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

    NASA Astrophysics Data System (ADS)

    Kuulkers, E.; Bozzo, E.; Bazzano, A.; Beckmann, V.; Bird, T.; Bodaghee, A.; Chenevez, J.; Del Santo, M.; Domingo, A.; Jonker, P.; Kretschmar, P.; Paizis, A.; Pottschmidt, K.; Markwardt, C.; Sanchez-Fernandez, C.; Wijnands, R.

    2015-02-01

    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.

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

    SciTech Connect

    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.

  13. The Hard X-Ray Emission from Scorpius X-1 Seen by INTEGRAL

    NASA Technical Reports Server (NTRS)

    Sturner, Steve; Shrader, C. R.

    2008-01-01

    We present the results of our hard X-ray and gamma-ray study of the LMXB Sco X-1 utilizing INTEGRAL data as well as contemporaneous RXTE PCA data. We have investigated the hard X-ray spectral properties of Sco X-1 including the nature of the high-energy, nonthermal component and its possible correlations with the location of the source on the soft X-ray color-color diagram. We find that Sco X-1 follows two distinct spectral tracks when the 20-40 keV count rate is greater than 130 counts/second. One state is a hard state which exhibits a significant high-energy, powerlaw tail to the lower energy thermal spectrum. The other state shows a much less significant high-energy component. We found suggestive evidence for a correlation of these hard and soft high-energy states with the position of Sco X-1 on the low-energy X-ray color-color diagram. We have searched for similar behavior in 2 other Z sources: GX 17+2 and GX 5-1 with negative results.

  14. A robot-based detector manipulator system for a hard x-ray nanoprobe instrument.

    SciTech Connect

    Shu, D., Maser, J., Holt, M. , Winarski, R., Preissner, C.,Lai, B., Vogt, S., Stephenson, G.B.

    2007-11-11

    This paper presents the design of a robot-based detector manipulator for microdiffraction applications with a hard X-ray nanoprobe instrument system being constructed at the Advanced Photon Source (APS) for the Center for Nanoscale Materials (CNM) being constructed at Argonne National Laboratory (ANL). Applications for detectors weighing from 1.5 to 100 kg were discussed in three configurations.

  15. High aspect ratio x-ray waveguide channels fabricated by e-beam lithography and wafer bonding

    SciTech Connect

    Neubauer, H.; Hoffmann, S.; Kanbach, M.; Haber, J.; Kalbfleisch, S.; Krüger, S. P.; Salditt, T.

    2014-06-07

    We report on the fabrication and characterization of hard x-ray waveguide channels manufactured by e-beam lithography, reactive ion etching and wafer bonding. The guiding layer consists of air or vacuum and the cladding material of silicon, which is favorable in view of minimizing absorption losses. The specifications for waveguide channels which have to be met in the hard x-ray range to achieve a suitable beam confinement in two orthogonal directions are extremely demanding. First, high aspect ratios up to 10{sup 6} have to be achieved between lateral structure size and length of the guides. Second, the channels have to be deeply embedded in material to warrant the guiding of the desired modes while absorbing all other (radiative) modes in the cladding material. We give a detailed report on device fabrication with the respective protocols and parameter optimization, the inspection and the optical characterization.

  16. Energetics of impulsive solar flares: Correlating BATSE hard x-ray bursts and the solar atmosphere's soft x-ray response

    NASA Technical Reports Server (NTRS)

    Newton, Elizabeth

    1996-01-01

    This investigation has involved the correlation of BATSE-observed solar hard X-ray emission with the characteristics of soft X-ray emitting plasma observed by the Yohkoh Bragg Crystal Spectrometers. The goal was to test the hypothesis that localized electron beam heating is the dominant energy transport mechanism in impulsive flares, as formulated in the thick-target electron-heated model of Brown.

  17. HEXITEC: A Next Generation Hard X-ray Detector for Solar Observations

    NASA Astrophysics Data System (ADS)

    Ryan, Daniel; Christe, Steven; Shih, Albert; Inglis, Andrew R.; Gregory, Kyle; Baumgartner, Wayne H.; Gaskin, Jessica; Wilson-Hodge, Colleen; Seller, Paul; Wilson, Matthew; Veale, Matthew C.; Panessa, Marco

    2016-05-01

    There is an increasing demand in solar physics for high resolution X-ray spectroscopic imaging. Such observations would present ground-breaking opportunities to study the poorly understood high energy processes in the solar corona such as solar flares, coronal heating, etc. However, such observations require a new breed of solid-state detectors sensititve to high energy X-rays with fine independent pixels to subsample the point spread function (PSF) of the X-ray optics. They must also be capable of handling very high count rates as photon fluxes from solar flares often cause pileup in current detectors. The Rutherford Appleton Laboratory (RAL) has recently developed a new Cadmium Telluride (CdTe) detector system, dubbed HEXITEC (High Energy X-ray Imaging Technology). It is an 80x80 array of 250 micron independent pixels sensitive in the 4--80 keV band and capable of a high full frame readout rate of 10 kHz. HEXITEC provides the smallest independently read out pixels currently available, and are well matched to the few arcsecond PSF produced by the current and next generation hard X-ray focusing optics. NASA's Goddard and Marshall Space Flight Centers are collaborating with RAL to develop these detectors for use on future space-borne hard X-ray focusing telescopes. In this poster we show the latest results on HEXITEC's imaging capability, high read out rate, and energy sensitivity and reveal it to be ideal for such future instruments. The potential observations obtained by combining HEXITEC with the next generation of X-ray focusing optics could to revolutionize our understanding of high energy processes in the solar corona.

  18. Probing bismuth ferrite nanoparticles by hard x-ray photoemission: Anomalous occurrence of metallic bismuth

    SciTech Connect

    Chaturvedi, Smita; Rajendra, Ranguwar; Ballav, Nirmalya; Kulkarni, Sulabha; Sarkar, Indranil; Shirolkar, Mandar M.; Jeng, U-Ser; Yeh, Yi-Qi

    2014-09-08

    We have investigated bismuth ferrite nanoparticles (∼75 nm and ∼155 nm) synthesized by a chemical method, using soft X-ray (1253.6 eV) and hard X-ray (3500, 5500, and 7500 eV) photoelectron spectroscopy. This provided an evidence for the variation of chemical state of bismuth in crystalline, phase pure nanoparticles. X-ray photoelectron spectroscopy analysis using Mg Kα (1253.6 eV) source showed that iron and bismuth were present in both Fe{sup 3+} and Bi{sup 3+} valence states as expected for bismuth ferrite. However, hard X-ray photoelectron spectroscopy analysis of the bismuth ferrite nanoparticles using variable photon energies unexpectedly showed the presence of Bi{sup 0} valence state below the surface region, indicating that bismuth ferrite nanoparticles are chemically inhomogeneous in the radial direction. Consistently, small-angle X-ray scattering reveals a core-shell structure for these radial inhomogeneous nanoparticles.

  19. Simulation and Laboratory results of the Hard X-ray Polarimeter: X-Calibur

    NASA Astrophysics Data System (ADS)

    Guo, Qingzhen; Beilicke, M.; Kislat, F.; Krawczynski, H.

    2014-01-01

    X-ray polarimetry promises to give qualitatively new information about high-energy sources, such as binary black hole (BH) systems, Microquasars, active galactic nuclei (AGN), GRBs, etc. 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 2014. X-Calibur combines a low-Z Compton scatterer with a CZT detector assembly to measure the polarization of 20- 80 keV X-rays making use of the fact that polarized photons Compton scatter preferentially perpendicular to the E field orientation. X-Calibur achieves a high detection efficiency of order unity. We optimized of the design of the instrument based on Monte Carlo simulations of polarized and unpolarized X-ray beams and of the most important background components. We have calibrated and tested X-Calibur extensively in the laboratory at Washington University and at the Cornell High-Energy Synchrotron Source (CHESS). Measurements using the highly polarized synchrotron beam at CHESS confirm the polarization sensitivity of the instrument. In this talk we report on the optimization of the design of the instrument based on Monte Carlo simulations, as well as results of laboratory calibration measurements characterizing the performance of the instrument.

  20. A hard X-ray study of the Jovian magnetosphere with NuSTAR

    NASA Astrophysics Data System (ADS)

    Mori, Kaya; Hailey, Charles James; Nynka, Melania; Grefenstette, Brian

    2016-01-01

    We report the first high-resolution hard X-ray observation of Jupiter with Nuclear Spectroscopic Telescope Array (NuSTAR) in February 2015. This observation was targeted to probing a high energy extension of the X-ray continuum component detected from the Jovian aurorae by XMM-Newton, while the previous in-situ observation by the Ulysses failed to detect hard X-ray emission in the 27-48 keV band. NuSTAR has the unique capabilities of spatially resolving the two polar regions above 10 keV and detecting a spectral break which is expected between the XMM-Newton and Ulysses energy band. With 100 ksec exposure, our detection of X-ray emission from the south pole was only marginal possibly due to time variation of the auroral X-ray emission, while the north pole was hidden during our observation. In this poster, we present our imaging and spectral analysis, then discuss follow-up deeper NuSTAR observations.

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

    SciTech Connect

    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.

  2. High-resolution high-efficiency multilayer Fresnel zone plates for soft and hard x-rays

    NASA Astrophysics Data System (ADS)

    Sanli, Umut T.; Keskinbora, Kahraman; Gregorczyk, Keith; Leister, Jonas; Teeny, Nicolas; Grévent, Corinne; Knez, Mato; Schütz, Gisela

    2015-09-01

    X-ray microscopy enables high spatial resolutions, high penetration depths and characterization of a broad range of materials. Calculations show that nanometer range resolution is achievable in the hard X-ray regime by using Fresnel zone plates (FZPs) if certain conditions are satisfied. However, this requires, among other things, aspect ratios of several thousands. The multilayer (ML) type FZPs, having virtually unlimited aspect ratios, are strong candidates to achieve single nanometer resolutions. Our research is focused on the fabrication of ML-FZPs which encompasses deposition of multilayers over a glass fiber via the atomic layer deposition (ALD), which is subsequently sliced in the optimum thickness for the X-ray energy by a focused ion beam (FIB). We recently achieved aberration free imaging by resolving 21 nm features with an efficiency of up to 12.5 %, the highest imaging resolution achieved by an ML-FZP. We also showed efficient focusing of 7.9 keV X-rays down to 30 nm focal spot size (FWHM). For resolutions below ~10 nm, efficiencies would decrease significantly due to wave coupling effects. To compensate this effect high efficiency, low stress materials have to be researched, as lower intrinsic stresses will allow fabrication of larger FZPs with higher number of zones, leading to high light intensity at the focus. As a first step we fabricated an ML-FZP with a diameter of 62 μm, an outermost zone width of 12 nm and 452 active zones. Further strategies for fabrication of high resolution high efficiency multilayer FZPs will also be discussed.

  3. HARD X-RAY AND MICROWAVE EMISSIONS FROM SOLAR FLARES WITH HARD SPECTRAL INDICES

    SciTech Connect

    Kawate, T.; Nishizuka, N.; Oi, A.; Ohyama, M.; Nakajima, H.

    2012-03-10

    We analyze 10 flare events that radiate intense hard X-ray (HXR) emission with significant photons over 300 keV to verify that the electrons that have a common origin of acceleration mechanism and energy power-law distribution with solar flares emit HXRs and microwaves. Most of these events have the following characteristics. HXRs emanate from the footpoints of flare loops, while microwaves emanate from the tops of flare loops. The time profiles of the microwave emission show delays of peak with respect to those of the corresponding HXR emission. The spectral indices of microwave emissions show gradual hardening in all events, while the spectral indices of the corresponding HXR emissions are roughly constant in most of the events, though rather rapid hardening is simultaneously observed in some for both indices during the onset time and the peak time. These characteristics suggest that the microwave emission emanates from the trapped electrons. Then, taking into account the role of the trapping of electrons for the microwave emission, we compare the observed microwave spectra with the model spectra calculated by a gyrosynchrotron code. As a result, we successfully reproduce the eight microwave spectra. From this result, we conclude that the electrons that have a common acceleration and a common energy distribution with solar flares emit both HXR and microwave emissions in the eight events, though microwave emission is contributed to by electrons with much higher energy than HXR emission.

  4. HARD X-RAY AND ULTRAVIOLET EMISSION DURING THE 2011 JUNE 7 SOLAR FLARE

    SciTech Connect

    Inglis, A. R.; Gilbert, H. R.

    2013-11-01

    The relationship between X-ray and UV emission during flares, particularly in the context of quasi-periodic pulsations, remains unclear. To address this, we study the impulsive X-ray and UV emission during an eruptive flare on 2011 June 7 utilizing X-ray imaging from RHESSI and UV 1700 Å imaging from SDO/AIA. This event is associated with quasi-periodic pulsations in X-ray and possibly UV emission, as well as substantial parallel and perpendicular motion in the hard X-ray footpoints. The motion of the footpoints parallel to the flare ribbons is unusual; it reverses direction on at least two occasions. However, there is no associated short timescale motion of the UV bright regions. Over the same time interval, the footpoints also gradually move apart at v ≈ 12 km s{sup –1}, consistent with the gradual outward expansion of the UV ribbons and the standard flare model. Additionally, we find that the locations of the brightest X-ray and UV regions are different, particularly during the early portion of the flare impulsive phase, despite their integrated emission being strongly correlated in time. Correlation analysis of measured flare properties, such as the footpoint separation, flare shear, photospheric magnetic field, and coronal reconnection rate, reveals that—in the impulsive phase—the 25-50 keV hard X-ray flux is only weakly correlated with these properties, in contrast with previous studies. We characterize this event in terms of long-term behavior, where the X-ray non-thermal, thermal, and UV emission sources appear temporally and spatially consistent, and short-term behavior, where the emission sources are inconsistent and quasi-periodic pulsations are a dominant feature requiring explanation. We suggest that the short timescale behavior of hard X-ray footpoints and the nature of the observed quasi-periodic pulsations are determined by fundamental, as yet unobserved properties of the reconnection region and particle acceleration sites. This presents a

  5. Weak Hard X-ray Emission from Broad Absorption Line Quasars Observed with NuSTAR: Evidence for Intrinsic X-ray Weakness

    NASA Astrophysics Data System (ADS)

    Luo, Bin; Brandt, W. Niel; Alexander, David M; Stern, Daniel; Teng, Stacy H.; Arevalo, Patricia; Bauer, Franz E.; Boggs, Steven E.; Christensen, Finn; Comastri, Andrea; Craig, William W.; Farrah, Duncan; Gandhi, Poshak; Hailey, Charles James; Harrison, Fiona; Koss, Michael; Ogle, Patrick M.; Puccetti, Simonetta; Saez, Cristian; Scott, Amy; Walton, Dom; Zhang, William

    2014-08-01

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

  6. A study of starting time in great hard X-ray flares

    NASA Technical Reports Server (NTRS)

    Klein, K. L.; Pick, M.; Magun, A.

    1986-01-01

    An analysis of the starting time in ten great hard X-ray bursts observed with the X-Ray Burst Spectrometer (HXRBS) is presented. It is shown that the impulsive phase of nine of them is composed of a preflash phase, during which the burst is observed up to an energy limit ranging from some tens of keV to 200 keV, followed ten to some tens of seconds afterwards by a flash phase, where the count rate rises simultaneously in all detector channels. For two events strong gamma-ray line emission is observed and is shown to start close to the onset of the flash phase.

  7. A simple hard x-ray ''nanoslit'' for measuring wavefront intensity

    SciTech Connect

    Takano, Hidekazu; Hashimoto, Takuto; Tsuji, Takuya; Koyama, Takahisa; Tsusaka, Yoshiyuki; Kagoshima, Yasushi

    2010-07-15

    A new method is proposed for nanoscale hard x-ray measurements. This method uses a reflection on a heavy-metal wire that functions as a single slit with a nanoscale aperture for a parallel x-ray beam. This ''nanoslit'' can be used to perform high-spatial-resolution measurements of the intensity distribution of a wavefront that diverges from an aperture. In experiments, Fresnel fringes generated by a rectangular aperture were measured using a 300-{mu}m-diameter platinum wire as the nanoslit. In these experiments, the finest fringes with a period of 26 nm could be successfully resolved.

  8. Optical optimization for anti-coincidence detectors of a Hard X-ray Modulation Telescope

    NASA Astrophysics Data System (ADS)

    Li, Yun-Long; Zhang, Chen; Zhang, Zhao; Fu, Min-Xue; Chen, Yi-Bao; Zhao, Dong-Hua; Deng, Jing-Kang; Shang, Ren-Cheng

    2016-01-01

    The anti-coincidence detectors of Hard X-ray Modulation Telescope (HXMT) are designed to suppress the X-ray background induced by incident charged cosmic-ray particles. The main components of anti-coincidence detectors are thin flat plastic scintillators. In this work we apply the TracePro program to study the light transfer features in the scintillators, and we propose several optimized reflector configurations to significantly improve the light transfer efficiency. The simulation results are verified by measurements of the detector prototypes. We chose a particular optimized reflector configuration.

  9. A simple cross-correlation technique between infrared and hard x-ray pulses.

    SciTech Connect

    Kraessig, B.; Dunford, R. W.; Kanter, E. P.; Landahl, E. C.; Southworth, S. H.; Young, L.; Chemical Sciences and Engineering Division

    2009-04-27

    We report a gas phase technique to establish the temporal overlap of ultrafast infrared laser and hard x-ray pulses. We use tunnel ionization of a closed shell atom in the strong field at the focus of an infrared laser beam to open a distinct x-ray absorption resonance channel with a clear fluorescence signature. The technique has an intrinsic response of a few femtoseconds and is nondestructive to the two beams. It provides a step-functionlike cross-correlation result. The details of the transient provide a diagnostic of the temporal overlap of the two pulses.

  10. Hard x-ray phase contrast imaging of black lipid membranes

    SciTech Connect

    Beerlink, A.; Mell, M.; Tolkiehn, M.; Salditt, T.

    2009-11-16

    We report hard x-ray phase contrast imaging of black lipid membranes, freely suspended over a micromachined aperture in an aqueous solution. Biomolecular and organic substances can thus be probed in hydrated environments by parallel beam propagation imaging, using coherent multi-kilo-electronvolt x-ray radiation. The width of the thinning film can be resolved from analysis of the intensity fringes in the Fresnel diffraction regime down to about 200 nm. The thinning process, in which solvent is expelled from the space in between two opposing monolayers, is monitored, and the domain walls between coexisting domains of swollen and thinned membrane patches are characterized.

  11. Towards multi-order hard X-ray imaging with multilayer zone plates

    PubMed Central

    Osterhoff, Markus; Eberl, Christian; Döring, Florian; Wilke, Robin N.; Wallentin, Jesper; Krebs, Hans-Ulrich; Sprung, Michael; Salditt, Tim

    2015-01-01

    This article describes holographic imaging experiments using a hard X-ray multilayer zone plate (MZP) with an outermost zone width of 10 nm at a photon energy of 18 keV. An order-sorting aperture (OSA) is omitted and emulated during data analysis by a ‘software OSA’. Scanning transmission X-ray microscopy usually carried out in the focal plane is generalized to the holographic regime. The MZP focus is characterized by a three-plane phase-retrieval algorithm to an FWHM of 10 nm. PMID:26089748

  12. The hard X-ray emission spectra from accretion columns in intermediate polars

    NASA Technical Reports Server (NTRS)

    Yi, Insu; Vishniac, Ethan T.

    1994-01-01

    We consider the hard (greater than 2 keV) X-ray emission from accretion columns in an intermediate polar system, GK Per, using a simple settling solution. The rate of photon emission per logarithmic energy interval can be fitted with a power law, E(exp -gamma), with gamma approximately 2.0, in agreement with observations. This index is only weakly dependent on the mass accretion rate, dot-M, for dot-M in the range of a few times 10(exp 16-18) g/s. The peak energy of the photon spectra (after photoelectric absorption) is expected to be E(sub p) approximately (5 keV) gamma(exp -1/3) (N(sub H)/10(exp 23)/sq cm)(exp 1/3) where N(sub H) is the hydrogen column density along the line of sight. The observed spectra of GK Per and possibly of V1223 Sgr suggest N(sub H) approximately 10(exp 23)/sq cm. This large N(sub H) may be due to partially ionized preshock column material. Alternatively, we also consider absorption by the cool outer parts of an accretion disk. In this case the photoelectric absorption depth in the disk is a sensitive function of inclination. For GK Per the required inclination is approximately 83 deg. For mass accretion rates larger than a critical rate of approximately 10(exp 18) g/s, X-ray emission from the column accretion is significantly affected by radiation drag. Although the mass accretion rate increases dramatically during outbursts, the observed hard (greater than 2 keV) X-ray luminosity will not rise proportionately. The slope and peak energy of the outburst spectra are only weakly affected. We conclude that the observed X-ray spectra can be explained by this simple analytic solution and that the production of hard X-rays from the accretion shock at the magnetic poles in the intermediate polars is in general agreement with the observations. However, since the X-ray emission and absorption depend on the mass accretion rate in a complicated manner, observed hard X-ray luminosities (greater than 2 keV) are not a good indicator of the mass

  13. One-dimensional hard x-ray field retrieval using a moveable structure

    SciTech Connect

    Guizar-Sicairos, M.; Evans-Lutterodt, K.; Isakovic, A.F.; Stein, A.; Warren, J.B.; Sandy, A.R.; Narayanan, S.; Fienup, J.R.

    2010-08-16

    We present a technique that allows measuring the field of an x-ray line focus using far-field intensity measurements only. One-dimensional phase retrieval with transverse translation diversity is used to recover a hard x-ray beam focused by a compound kinoform lens. The reconstruction is found to be in good agreement with independent knife-edge scan measurements taken at separated planes. The approach avoids the need for measuring the beam profile at focus and allows narrower beams to be measured than the traditional knife-edge scan.

  14. Observation of the Talbot effect using broadband hard x-ray beam

    SciTech Connect

    Kim, J.M.; Conley, R.; Cho, I. H.; Lee, S. Y.; Kang, H. C.; Liu, C.; Macrander, A. T.; Noh, D. Y.

    2010-11-15

    We demonstrated the Talbot effect using a broadband hard x-ray beam ({Delta}{lambda}/{lambda} {approx}1). The exit wave-field of the x-ray beam passing through a grating with a sub micro-meter scale period was successfully replicated and recorded at effective Talbot distance, Z{sub T}. The period was reduced to half at Z{sub T}/4 and 3/4Z{sub T}, and the phase reversal was observed at Z{sub T}/2. The propagating wave-field recorded on photoresists was consistent with a simulated result.

  15. Host Galaxy Properties of BAT Hard X-ray Selected AGN

    NASA Astrophysics Data System (ADS)

    Koss, Michael; Mushotzky, Richard; Veilleux, Sylvain; Winter, Lisa

    2010-07-01

    Surveys of AGN taken in the optical, UV, and soft X-rays miss an important population of obscured AGN only visible in the hard X-rays and mid-IR wavelengths. The SWIFT BAT survey in the hard X-ray range (14-195 keV) has provided a uniquely unbiased sample of 246 AGN unaffected by galactic or circumnuclear absorption [1]. Most of the sources in the survey are bright, Seyfert like AGN's with median redshift of 0.03. Of the AGN, 43% are obscured, type II AGN. We obtained 17 nights of imaging of 90 host galaxies of these AGN in 2008 at the Kitt Peak 2.1 m telescope in the SDSS ugriz filters. For the broad line sources we subtracted the AGN contribution using GALFIT. By comparing our sample of AGN to inactive galaxies in the SDSS, we find that AGN are found in the most massive galaxies and are bluer in color than inactive galaxies of comparable stellar mass. We also find a correlation between the point source optical light and hard X-ray luminosity.

  16. Host Galaxy Properties of BAT Hard X-ray Selected AGN

    SciTech Connect

    Koss, Michael; Mushotzky, Richard; Veilleux, Sylvain; Winter, Lisa

    2010-07-15

    Surveys of AGN taken in the optical, UV, and soft X-rays miss an important population of obscured AGN only visible in the hard X-rays and mid-IR wavelengths. The SWIFT BAT survey in the hard X-ray range (14-195 keV) has provided a uniquely unbiased sample of 246 AGN unaffected by galactic or circumnuclear absorption [1]. Most of the sources in the survey are bright, Seyfert like AGN's with median redshift of 0.03. Of the AGN, 43% are obscured, type II AGN. We obtained 17 nights of imaging of 90 host galaxies of these AGN in 2008 at the Kitt Peak 2.1 m telescope in the SDSS ugriz filters. For the broad line sources we subtracted the AGN contribution using GALFIT. By comparing our sample of AGN to inactive galaxies in the SDSS, we find that AGN are found in the most massive galaxies and are bluer in color than inactive galaxies of comparable stellar mass. We also find a correlation between the point source optical light and hard X-ray luminosity.

  17. Quasi-periodic pulsations in solar hard X-ray and microwave flares

    NASA Technical Reports Server (NTRS)

    Kosugi, Takeo; Kiplinger, Alan L.

    1986-01-01

    For more than a decade, various studies have pointed out that hard X-ray and microwave time profiles of some solar flares show quasi-periodic fluctuations or pulsations. Nevertheless, it was not until recently that a flare displaying large amplitude quasi-periodic pulsations in X-rays and microwaves was observed with good spectral coverage and with a sufficient time resolution. The event occurred on June 7, 1980, at approximately 0312 UT, and exhibits seven intense pulses with a quasi-periodicity of approximately 8 seconds in microwaves, hard X-rays, and gamma-ray lines. On May 12, 1983, at approximately 0253 UT, another good example of this type of flare was observed both in hard X-rays and in microwaves. Temporal and spectral characteristics of this flare are compared with the event of June 7, 1980. In order to further explore these observational results and theoretical scenarios, a study of nine additional quasi-periodic events were incorporated with the results from the two flares described. Analysis of these events are briefly summarized.

  18. A conceptual design of hard X-ray focal plane detector for simultaneous x-ray polarimetric, spectroscopic, and timing measurements

    NASA Astrophysics Data System (ADS)

    Vadawale, S. V.; Chattopadhyay, T.; Pendharkar, J.

    2012-09-01

    Importance of polarisation measurement of X-rays from celestial sources has been realized for long time. Such measurements can provide unique opportunity to study the behaviour of matter and radiation under extreme magnetic and gravitational fields. However sensitivity of the X-ray polarimeters has always been an issue and as a result no X-ray polarization measurement has been flown in last three decades. The situation is expected to change in near future with launch of GEMS, but these polarisation measurements will be limited to energies below 10KeV. On the other hand most of the X-ray sources are expected to have higher degree of polarisation at higher energies. With the advent of high energy focussing telescopes (e.g. NuSTAR, ASTRO-H), it is now possible to design a focal plane Compton polarimeter which can be sensitive upto 80KeV. However, X-ray polarisation measurement is extremely photon hungry. Therefore, a dedicated X-ray polarimeter always has lower sensitivity when compared to any other type of X-ray detector for equal collecting area and time. In this context, we explore a new design of hard X-ray focal plane detector which can provide simultaneous measurements of X-ray polarisation measurements along with high resolution X-ray spectroscopy as well as timing. This design employs a sandwich of a 0.5mm thick Si detector and 10mm thick plastic detector which is surrounded by a cylindrical array of scintillator detectors. Here we present results of detailed Geant4 simulations for estimating sensitivity of this configuration.

  19. Development of a Prototype Nickel Optic for the Constellation-X Hard-X-Ray Telescope

    NASA Technical Reports Server (NTRS)

    Basso, S.; Bruni, R. J.; Citerio, O.; Engelhaupt, D.; Ghigo, M.; Gorenstien, P.; Mazzoleni, F.; ODell, S. L.; Pareschi, G.; Ramsey, B. D.

    2003-01-01

    The Constellation-X mission, planned for launch in 2011, will feature an array of hard-x ray telescopes with a total collecting area goal of 1500 square centimeters at 40 keV. Various technologies are currently being investigated for the optics of these telescopes including multilayer-coated Eletroformed-Nickel-Replicated (ENR) shells. The attraction of the ENR process is that the resulting full-shell optics are inherently stable and offer the promise of good angular resolution and enhanced instrument sensitivity. The challenge for this process is to meet a relatively tight weight budget with a relatively dense material (rho nickel = 9 grams per cubic centimeters.) To demonstrate the viability of the ENR process we are fabricating a prototype HXT mirror module to be tested against a competing segmented-glass-shell optic. The ENR prototype will consist of 5 shells of diameters from 150 mm to 280 mm and of 426 mm total length. To meet the stringent weight budget for Con-X, the shells will be only 150 micron thick. The innermost of these will be coated with Iridium, while the remainder will be coated with graded-density multilayers. Mandrels for these shells are currently under fabrication (Jan 03), with the first shells scheduled for production in February 03. A tentative date of late Summer has been set for prototype testing. Issues currently being addressed are the control of stresses in the multiplayer coating and ways of mitigating their effects on the figure of the necessarily thin shells. Also, the fabrication, handling and mounting of these shells without inducing permanent figure distortions. A full status report on the prototype optic will be presented along with test results as available.

  20. The column density distribution of hard X-ray radio galaxies

    NASA Astrophysics Data System (ADS)

    Panessa, F.; Bassani, L.; Landi, R.; Bazzano, A.; Dallacasa, D.; La Franca, F.; Malizia, A.; Venturi, T.; Ubertini, P.

    2016-09-01

    In order to investigate the role of absorption in active galactic nuclei (AGN) with jets, we have studied the column density distribution of a hard X-ray selected sample of radio galaxies, derived from the INTEGRAL/Imager on Board the Integral Satellite (IBIS) and Swift/The Burst Alert Telescope (BAT) AGN catalogues (˜7-10 per cent of the total AGN population). The 64 radio galaxies have a typical FR II radio morphology and are characterized by high 20-100 keV luminosities (from 1042 to 1046 erg s-1) and high Eddington ratios (log LBol/LEdd typically larger than ˜0.01). The observed fraction of absorbed AGN (NH > 1022 cm-2) is around 40 per cent among the total sample, and ˜75 per cent among type 2 AGN. The majority of obscured AGN are narrow-line objects, while unobscured AGN are broad-line objects, obeying to the zeroth-order predictions of unified models. A significant anti-correlation between the radio core dominance parameter and the X-ray column density is found. The observed fraction of Compton thick AGN is ˜2-3 per cent, in comparison with the 5-7 per cent found in radio-quiet hard X-ray selected AGN. We have estimated the absorption and Compton thick fractions in a hard X-ray sample containing both radio galaxies and non-radio galaxies and therefore affected by the same selection biases. No statistical significant difference was found in the absorption properties of radio galaxies and non-radio galaxies sample. In particular, the Compton thick objects are likely missing in both samples and the fraction of obscured radio galaxies appears to decrease with luminosity as observed in hard X-ray non-radio galaxies.

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

    NASA Technical Reports Server (NTRS)

    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.

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

    NASA Astrophysics Data System (ADS)

    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.

  3. Discovery of Diffuse Hard X-ray Emission associated with Jupiter

    NASA Astrophysics Data System (ADS)

    Ezoe, Y.; Miyoshi, Y.; Ishikawa, K.; Ohashi, T.; Terada, N.; Uchiyama, Y.; Negoro, H.

    2009-12-01

    Our discovery of diffuse hard (1-5 keV) X-ray emission around Jupiter is reported. Recent Chandra and XMM-Newton observations revealed several types of X-rays in the vicinity of Jupiter such as auroral and disk emission from Jupiter and faint diffuse X-rays from the Io Plasma Torus (see Bhardwaj et al. 2007 for review). To investigate possible diffuse hard X-ray emission around Jupiter with the highest sensitivity, we conducted data analysis of Suzaku XIS observations of Jupiter on Feb 2006. After removing satellite and planetary orbital motions, we detected a significant diffuse X-ray emission extending to ~6 x 3 arcmin with the 1-5 keV X-ray luminosity of ~3e15 erg/s. The emitting region very well coincided with the Jupiter's radiation belts. The 1-5 keV X-ray spectrum was represented by a simple power law model with a photon index of 1.4. Such a flat continuum strongly suggests non-thermal origin. Although such an emission can be originated from multiple background point sources, its possibility is quite low. We hence examined three mechanisms, assuming that the emission is truly diffuse: bremsstrahlung by keV electrons, synchrotron emission by TeV electrons, and inverse Compton scattering of solar photons by MeV electrons. The former two can be rejected because of the X-ray spectral shape and implausible existence of TeV electrons around Jupiter, respectively. The last possibility was found to be possible because tens MeV electrons, which have been confirmed in inner radiation belts (Bolton et al. 2002), can kick solar photons to the keV energy range and provide a simple power-law continuum. We estimated an average electron density from the X-ray luminosity assuming the oblate spheroid shaped emitting region with 8 x 8 x 4 Jovian radii. The necessary density was 0.02 1/cm3 for 50 MeV electrons. Hence, our results may suggest a new particle acceleration phenomenon around Jupiter.

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

    NASA Technical Reports Server (NTRS)

    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.

  5. Multiphoton ionization and fragmentation of iodine-containing molecules by femtosecond ultraintense hard X-rays

    NASA Astrophysics Data System (ADS)

    Robatjazi, S. J.; Li, X.; Rolles, D.; Rudenko, A.; Erk, B.; Boll, R.; Bomme, C.; Savelyev, E.; Rudek, B.; Foucar, L.; Bostedt, Ch.; Southworth, S.; Lehmann, C. S.; Kraessig, B.; Young, L.; Marchenko, T.; Simon, M.; Ueda, K.; Ferguson, K. R.; Bucher, M.; Gorkhover, T.; Carron, S.; Alonso-Mori, R.; Williams, G.; Boutet, S.

    2016-05-01

    We present ion charge state distributions and kinetic energy spectra resulting from the breakup of CH3 I and C6 H5 I molecules induced by femtosecond X-ray pulses from the Linac Coherent Light Source (LCLS) at 8.3 keV photon energy. Using a few-hundred nm focus of the LCLS CXI beamline, we reach peak intensities of up to 1020 W/ cm2, resulting in stripping of more than 50 electrons per molecule within few tens of fs. We find that in this regime the interplay between multiphoton absorption and subsequent charge rearrangement considerably differs from earlier observations for soft X-rays or for weaker hard X-rays. We discuss the pulse duration dependence of the data, and compare the results for seeded and unseeded LCLS pulses. Supported by the Chemical Sciences, Geosciences, and Biosciences Division, Office of Basic Energy Sciences, Office of Science, U. S. DOE.

  6. Laue diffraction hard x-ray spectrometer for laser fusion diagnostics

    SciTech Connect

    Priedhorsky, W.C.; Lier, D.W.; Day, R.H.

    1983-12-01

    We show that a crystal spectrometer used in the Laue mode is a useful diagnostic of high-energy x-ray emission from laser fusion plasmas. It has good collection efficiency and adequate energy resolution for continuum measurements. The instrument measures time integrated x-ray spectra with a resolving power E/..delta..Eroughly-equal10 for photon energies between 60 and 300 keV. A strong signal and no detectable background are obtained in laser fusion experiments where approx.15 J of x rays are released in a pulsed (1 ns), hard (kTroughly-equal200 keV) spectrum. A Lanex/Tri-X phosphor/film combination is used as a focal plane detector; we report its relative energy calibration. Because of the imperfection of available crystals, detailed measurements of reflectivity along the crystal are required to achieve absolute calibration.

  7. Laué diffraction hard x-ray spectrometer for laser fusion diagnostics

    NASA Astrophysics Data System (ADS)

    Priedhorsky, W. C.; Lier, D. W.; Day, R. H.

    1983-12-01

    We show that a crystal spectrometer used in the Laué mode is a useful diagnostic of high-energy x-ray emission from laser fusion plasmas. It has good collection efficiency and adequate energy resolution for continuum measurements. The instrument measures time integrated x-ray spectra with a resolving power E/ΔE≊10 for photon energies between 60 and 300 keV. A strong signal and no detectable background are obtained in laser fusion experiments where ˜15 J of x rays are released in a pulsed (1 ns), hard (kT≊200 keV) spectrum. A Lanex/Tri-X phosphor/film combination is used as a focal plane detector; we report its relative energy calibration. Because of the imperfection of available crystals, detailed measurements of reflectivity along the crystal are required to achieve absolute calibration.

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

    NASA Astrophysics Data System (ADS)

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

    PubMed

    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

    2011-01-01

    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 4×10(17)W/cm(2) was obtained at 70 fs pulse length. PMID:22355576

  10. CLESSIDRA: Focusing Hard X-Rays Efficiently with Arrays Composed of Small Prisms

    SciTech Connect

    Jark, Werner; Perennes, Frederic; Matteucci, Marco; Mancini, Lucia; Menk, Ralf H.; Rigon, Luigi

    2007-01-19

    Small prisms arranged such that the number of prisms to traverse by an x-ray beam is linearly increasing with distance from the symmetry axis of the device will direct an incident wave to a common cross over point. This structure can be understood as a special form of the Fresnel version of a concave refractive x-ray lens. Indeed it is obtained by removing blocks of optically passive material of equal height from the concave lens shape. It will be shown that the structure has a high refraction efficiency and that the losses are produced by problems in the fabrication of sufficiently sharp tips for the prisms.

  11. ON THE NATURE OF HARD X-RAY EXTRAGALACTIC SOURCES OBSERVED WITH XMM-NEWTON

    SciTech Connect

    Jimenez-Bailon, E.; Huerta, E. M.; Krongold, Y.; Chavushyan, V.; Schartel, N.; Santos-Lleo, M.

    2012-03-15

    Over the last decade, X-ray surveys have provided outstanding new results due to the lack of the common selection effects present at other wavelengths. Here, we have selected a sample of unidentified sources from the XMM-Newton Slew Survey Catalog, likely to be extragalactic. Five of them were observed with the XMM-Newton observatory. In this work, we present the results of the spectral analysis of these objects in the X-ray and optical bands. Only three of them had useful spectroscopic X-ray data, and follow up observations were carried out in the optical range to determine their coordinates, classification, and redshift. The sources are different types of active galactic nuclei (AGNs) with redshifts ranging from 0.059 to 0.386. The properties at both spectral ranges (X-rays and optical) are compatible with the common properties of their types of AGNs. Although the sources were selected by their hard X-ray properties, none of the three detected objects turned out to be an obscured AGN.

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

    PubMed

    Szlachetko, J; Milne, C J; Hoszowska, J; Dousse, J-Cl; Błachucki, W; Sà, J; Kayser, Y; Messerschmidt, M; Abela, R; Boutet, S; David, C; Williams, G; Pajek, M; Patterson, B D; Smolentsev, G; van Bokhoven, J A; Nachtegaal, M

    2014-03-01

    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. PMID:26798772

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

    NASA Astrophysics Data System (ADS)

    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.

  14. Hard X-Ray Emission and the Ionizing Source in LINERs

    NASA Technical Reports Server (NTRS)

    Terashima, Yuichi; Ho, Luis C.; Ptak, Andrew F.

    2000-01-01

    We report X-ray fluxes in the 2-10 keV band from LINERs (low-ionization nuclear emission-line regions) and low-luminosity Seyfert galaxies obtained with the ASCA satellite. Observed X-ray luminosities are in the range between 4 x 10(exp 39) and 5 x 10(exp 41) ergs/s, which are significantly smaller than that of the "classical" low-luminosity Seyfert 1 galaxy NGC 4051. We found that X-ray luminosities in 2-10 keV of LINERs with broad H.alpha emission in their optical spectra (LINER 1s) are proportional to their Ha luminosities. This correlation strongly supports the hypothesis that the dominant ionizing source in LINER 1s is photoionization by hard photons from low-luminosity AGNs. On the other hand, the X-ray luminosities of most LINERs without broad H.alpha emission (LINER 2s) in our sample are lower than LINER 1s at a given H.alpha luminosity. The observed X-ray luminosities in these objects are insufficient to power their H.alpha luminosities, suggesting that their primary ionizing source is other than an AGN, or that an AGN, if present, is obscured even at energies above 2 keV.

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

    PubMed Central

    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

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

    PubMed Central

    Szlachetko, J.; Milne, C. J.; Hoszowska, J.; Dousse, J.-Cl.; Błachucki, W.; Sà, J.; Kayser, Y.; Messerschmidt, M.; Abela, R.; Boutet, S.; David, C.; Williams, G.; Pajek, M.; Patterson, B. D.; Smolentsev, G.; van Bokhoven, J. A.; Nachtegaal, M.

    2014-01-01

    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. PMID:26798772

  17. DISCOVERY OF DIFFUSE HARD X-RAY EMISSION AROUND JUPITER WITH SUZAKU

    SciTech Connect

    Ezoe, Y.; Ishikawa, K.; Ohashi, T.; Miyoshi, Y.; Terada, N.; Uchiyama, Y.; Negoro, H.

    2010-02-01

    We report the discovery of diffuse hard (1-5 keV) X-ray emission around Jupiter in a deep 160 ks Suzaku X-ray Imaging Spectrometer data. The emission is distributed over {approx}16 x 8 Jovian radius and spatially associated with the radiation belts and the Io Plasma Torus (IPT). It shows a flat power-law spectrum with a photon index of 1.4 {+-} 0.2 with the 1-5 keV X-ray luminosity of (3.3 {+-} 0.5)x10{sup 15} erg s{sup -1}. We discussed its origin and concluded that it seems to be truly diffuse, although a possibility of multiple background point sources cannot be completely rejected with a limited angular resolution. If it is diffuse, the flat continuum indicates that X-rays arise by the nonthermal electrons in the radiation belts and/or the IPT. The synchrotron and bremsstrahlung models can be rejected from the necessary electron energy and X-ray spectral shape, respectively. The inverse-Compton scattering off solar photons by ultra-relativistic (several tens MeV) electrons can explain the energy and the spectrum but the necessary electron density is {approx}>10 times larger than the value estimated from the empirical model of Jovian charge particles.

  18. Comparison of hard and soft x-ray photoelectron spectra of silicon

    NASA Astrophysics Data System (ADS)

    Offi, F.; Werner, W. S. M.; Sacchi, M.; Torelli, P.; Cautero, M.; Cautero, G.; Fondacaro, A.; Huotari, S.; Monaco, G.; Paolicelli, G.; Smekal, W.; Stefani, G.; Panaccione, G.

    2007-08-01

    A detailed comparison of the surface sensitivity of x-ray photoemission spectroscopy for hard and soft x rays is presented and discussed. Electron scattering parameters and their energy dependence are given for Si and two Si spectra are analyzed: a MgKα (hν=1253.6eV) excited spectrum of the Si2p and 2s lines and a hard x-ray excited spectrum (hν=5925eV) of the Si1s line. The differential inelastic scattering characteristics for Si are extracted from reflection electron energy loss spectra taken at energies of 1500 and 4000eV . Using these scattering characteristics and electron mean free paths from the literature, simulated spectra are compared with experiment. The experimental spectra are deconvoluted to give the true intrinsic line shape corresponding to the theoretical collision statistics when interference effects between intrinsic and extrinsic scattering are neglected. The magnitude of interference effects cannot be assessed by our analysis. Within the (unknown) uncertainty introduced by neglecting interference effects, it is possible to determine the relative intensity of intrinsic and extrinsic excitations. In this way, it is found that in the case of the soft x-ray excited photoelectron spectrum of the shallower electronic shells ( 2p and 2s ), intrinsic plasmon creation is rather weak, and the apparent asymmetric line shape of the spectrum might be interpreted as the fact that electron-hole pair creation dominates the intrinsic loss spectrum, while an alternative explanation in terms of surface core level shifted components is also proposed. For the deeper core electronic shell, probed with hard x rays, the opposite situation is observed: while intrinsic electron-hole pair creation was not observed, a strong contribution of intrinsic plasmon losses of about 30% was seen.

  19. Development of High Resolution Hard X-Ray Telescope with Multi-Layer Coatings

    NASA Technical Reports Server (NTRS)

    Gorenstein, Paul; Brinton, John C. (Technical Monitor)

    2005-01-01

    This is the annual report for the third year of a three-year program. Previous annual reports have described progress achieved in the first and second years. The major objective of this program is the development of a focusing hard X-ray telescope with moderately high angular resolution, i.e. comparable to the telescopes of XMM-Newton. The key ingredients of the telescope are a depth graded multilayer coatings and electroformed nickel substrates that are considerably lighter weight than those of previous missions such as XMM-Newton, which have had conventional single metal layer reflective coatings and have operated at much lower energy X-rays. The ultimate target mission for this technology is the Hard X-Ray Telescope (HXT) of the Constellation X-Ray Mission. However, it is applicable to potential SMEX and MIDEX programs as well. We are building upon technology that has proven to be successful in the XMM-Newton and SWIFT missions. The improvements that we are adding are a significant reduction in mass without much loss of angular resolution and an order of magnitude extension of the bandwidth through the use of multilayer coatings. The distinctive feature of this approach compared to those of other hard X-ray telescope programs is that we expect the angular resolution to be superior than telescopes made by other methods thanks to the structural integrity of the substrates. They are thin walled complete cylinders of revolution with a Wolter Type 1 figure; the front half is a parabola, the rear half a hyperbola.

  20. Optimization of the reflecting coatings for the new hard x-ray mission

    NASA Astrophysics Data System (ADS)

    Cotroneo, V.; Pareschi, G.; Spiga, D.; Tagliaferri, G.

    2009-08-01

    The design of the next generation of hard-X-ray focusing telescopes requires highly optimized reflecting coatings, with the maximum efficiency over a broad energy band and a relatively large field of view. Multilayer coatings based on layer thicknesses with power-law distribution are often considered as a convenient solution to achieve angular and energetic broad band reflection of X-ray at grazing incidence, being also particularly suitable for numerical optimization. In this work we consider the optimization of the telescope for the New Hard X-ray Mission, an Italian project based on four optical modules with multilayer-coated Nickel-replicated Wolter optics, able to focus high-energy X-ray radiation (up to 80 keV) with good imaging resolution (20 arcsec HEW). The optimization of the telescope was studied from the point of view of shell sizes, coating materials and multilayer structures. In particular, the best structure of the coating is determined by means of numerical optimization methods introducing also the number of layers as optimization parameters. Very effective solutions are found even with a low number of bilayers (~100).

  1. Advanced experimental applications for x-ray transmission gratings spectroscopy using a novel grating fabrication method.

    PubMed

    Hurvitz, G; Ehrlich, Y; Strum, G; Shpilman, Z; Levy, I; Fraenkel, M

    2012-08-01

    A novel fabrication method for soft x-ray transmission grating and other optical elements is presented. The method uses focused-ion-beam technology to fabricate high-quality free standing grating bars on transmission electron microscopy grids. High quality transmission gratings are obtained with superb accuracy and versatility. Using these gratings and back-illuminated CCD camera, absolutely calibrated x-ray spectra can be acquired for soft x-ray source diagnostics in the 100-3000 eV spectral range. Double grating combinations of identical or different parameters are easily fabricated, allowing advanced one-shot application of transmission grating spectroscopy. These applications include spectroscopy with different spectral resolutions, bandwidths, dynamic ranges, and may serve for identification of high-order contribution, and spectral calibrations of various x-ray optical elements. PMID:22938276

  2. Advanced experimental applications for x-ray transmission gratings spectroscopy using a novel grating fabrication method

    NASA Astrophysics Data System (ADS)

    Hurvitz, G.; Ehrlich, Y.; Strum, G.; Shpilman, Z.; Levy, I.; Fraenkel, M.

    2012-08-01

    A novel fabrication method for soft x-ray transmission grating and other optical elements is presented. The method uses focused-ion-beam technology to fabricate high-quality free standing grating bars on transmission electron microscopy grids. High quality transmission gratings are obtained with superb accuracy and versatility. Using these gratings and back-illuminated CCD camera, absolutely calibrated x-ray spectra can be acquired for soft x-ray source diagnostics in the 100-3000 eV spectral range. Double grating combinations of identical or different parameters are easily fabricated, allowing advanced one-shot application of transmission grating spectroscopy. These applications include spectroscopy with different spectral resolutions, bandwidths, dynamic ranges, and may serve for identification of high-order contribution, and spectral calibrations of various x-ray optical elements.

  3. Possibility of gated silicon drift detector detecting hard x-ray

    NASA Astrophysics Data System (ADS)

    Matsuura, Hideharu; Fukushima, Shinya; Sakurai, Shungo; Ishikawa, Shohei; Takeshita, Akinobu; Hidaka, Atsuki

    2015-08-01

    One of the authors has proposed a simple-structure silicon X-ray detector (gated silicon drift detector: GSDD), whose structure is much simpler than commercial silicon drift detectors (SDDs). SDDs contain multiple built-in metal-oxide-semiconductor field-effect transistors (MOSFETs) or implanted resistors, whose fabrication processes lower the yield rate of detectors, and also require at least two high-voltage sources. On the other hand, GSDDs do not contain built-in MOSFETs or implanted resistors. Moreover, GSDDs require only one high-voltage source. Therefore, GSDDs greatly reduce the cost of the X-ray detection system. We fabricated prototype GSDDs that contained 0.625-mm-thick Si substrates with an active area of 18 mm2, operated by Peltier cooling and a single voltage source. Its energy resolution at 5.9 keV from an 55Fe source was 145 eV at -38°C and -90°V. Thicker Si substrates are required to enhance its absorption of X-rays. To detect X-ray photons with energies up to 77 keV for X-ray absorbance higher than 15%, we simulate the electric potential distribution in GSDDs with Si thicknesses from 0.625 to 3.0 mm. We obtain an adequate electric potential distribution in the thicknesses of up to 3.0 mm, and the capacitance of the GSDD remains small and its X-ray count rate remain high. The high reverse bias required in the 3-mm-thick GSDD was a third of that in a 3-mm-thick pin diode.

  4. Simbol-X Hard X-ray Focusing Mirrors: Results Obtained During the Phase A Study

    NASA Astrophysics Data System (ADS)

    Tagliaferri, G.; Basso, S.; Borghi, G.; Burkert, W.; Citterio, O.; Civitani, M.; Conconi, P.; Cotroneo, V.; Freyberg, M.; Garoli, D.; Gorenstein, P.; Hartner, G.; Mattarello, V.; Orlandi, A.; Pareschi, G.; Romaine, S.; Spiga, D.; Valsecchi, G.; Vernani, D.

    2009-05-01

    Simbol-X will push grazing incidence imaging up to 80 keV, providing a strong improvement both in sensitivity and angular resolution compared to all instruments that have operated so far above 10 keV. The superb hard X-ray imaging capability will be guaranteed by a mirror module of 100 electroformed Nickel shells with a multilayer reflecting coating. Here we will describe the technogical development and solutions adopted for the fabrication of the mirror module, that must guarantee an Half Energy Width (HEW) better than 20 arcsec from 0.5 up to 30 keV and a goal of 40 arcsec at 60 keV. During the phase A, terminated at the end of 2008, we have developed three engineering models with two, two and three shells, respectively. The most critical aspects in the development of the Simbol-X mirrors are i) the production of the 100 mandrels with very good surface quality within the timeline of the mission, ii) the replication of shells that must be very thin (a factor of 2 thinner than those of XMM-Newton) and still have very good image quality up to 80 keV, iii) the development of an integration process that allows us to integrate these very thin mirrors maintaining their intrinsic good image quality. The Phase A study has shown that we can fabricate the mandrels with the needed quality and that we have developed a valid integration process. The shells that we have produced so far have a quite good image quality, e.g. HEW <~30 arcsec at 30 keV, and effective area. However, we still need to make some improvements to reach the requirements. We will briefly present these results and discuss the possible improvements that we will investigate during phase B.

  5. Weak Hard X-Ray Emission from Two Broad Absorption Line Quasars Observed with NuStar: Compton-Thick Absorption or Intrinsic X-Ray Weakness?

    NASA Technical Reports Server (NTRS)

    Luo, B.; Brandt, W. N.; Alexander, D. M.; Harrison, F. A.; Stern, D.; Bauer, F. E.; Boggs, S. E.; Christensen, F. E.; Comastri, A.; Craig, W. W..; Fabian, A. C.; Farrah, D.; Fiore, F.; Fuerst, F.; Grefenstette, B. W.; Hailey, C. J.; Hickox, R.; Madsen, K. K.; Matt, G.; Ogle, P.; Risaliti, G.; Saez, C.; Teng, S. H.; Walton, D. J.; Zhang, W. W.

    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 approx. or equal to 400-600 hard X-ray (is greater than or equal to 10 keV) photons with NuSTAR, provided that these photons are not significantly absorbed N(sub H) is less than or equal to 10(exp24) cm(exp-2). However, both BAL quasars are only detected in the softer NuSTAR bands (e.g., 4-20 keV) but not in its harder bands (e.g., 20-30 keV), suggesting that either the shielding gas is highly Compton-thick or the two targets are intrinsically X-ray weak. We constrain the column densities for both to be N(sub H) 7 × 10(exp 24) cm(exp-2) if the weak hard X-ray emission is caused by obscuration from the shielding gas. We discuss a few possibilities for how PG 1004+130 could have Compton-thick shielding gas without strong Fe Ka line emission; dilution from jet-linked X-ray emission is one likely explanation. We also discuss the intrinsic X-ray weakness scenario based on a coronal-quenching model relevant to the shielding gas and disk wind of BAL quasars. Motivated by our NuSTAR results, we perform a Chandra stacking analysis with the Large Bright Quasar Survey BAL quasar sample and place statistical constraints upon the fraction of intrinsically X-ray weak BAL quasars; this fraction is likely 17%-40%.

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

    SciTech Connect

    Luo, B.; Brandt, W. N.; Alexander, D. M.; Hickox, R.; Harrison, F. A.; Fuerst, F.; Grefenstette, B. W.; Madsen, K. K.; Stern, D.; Bauer, F. E.; Boggs, S. E.; Craig, W. W.; Christensen, F. E.; Comastri, A.; Fabian, A. C.; Farrah, D.; Fiore, F.; Hailey, C. J.; Matt, G.; Ogle, P.; and others

    2013-08-01

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

  7. Development of a Direct Fabrication Technique for Full-Shell X-Ray Optics

    NASA Technical Reports Server (NTRS)

    Gubarev, M.; Kolodziejczak, J. K.; Griffith, C.; Roche, J.; Smith, W. S.; Kester, T.; Atkins, C.; Arnold, W.; Ramsey, B.

    2016-01-01

    Future astrophysical missions will require fabrication technology capable of producing high angular resolution x-ray optics. A full-shell direct fabrication approach using modern robotic polishing machines has the potential for producing high resolution, light-weight and affordable x-ray mirrors that can be nested to produce large collecting area. This approach to mirror fabrication, based on the use of the metal substrates coated with nickel phosphorous alloy, is being pursued at MSFC. The design of the polishing fixtures for the direct fabrication, the surface figure metrology techniques used and the results of the polishing experiments are presented.

  8. Compton polarimeter as a focal plane detector for hard X-ray telescope: sensitivity estimation with Geant4 simulations

    NASA Astrophysics Data System (ADS)

    Chattopadhyay, T.; Vadawale, S. V.; Pendharkar, J.

    2013-04-01

    X-ray polarimetry can be an important tool for investigating various physical processes as well as their geometries at the celestial X-ray sources. However, X-ray polarimetry has not progressed much compared to the spectroscopy, timing and imaging mainly due to the extremely photon-hungry nature of X-ray polarimetry leading to severely limited sensitivity of X-ray polarimeters. The great improvement in sensitivity in spectroscopy and imaging was possible due to focusing X-ray optics which is effective only at the soft X-ray energy range. Similar improvement in sensitivity of polarisation measurement at soft X-ray range is expected in near future with the advent of GEM based photoelectric polarimeters. However, at energies >10 keV, even spectroscopic and imaging sensitivities of X-ray detector are limited due to lack of focusing optics. Thus hard X-ray polarimetry so far has been largely unexplored area. On the other hand, typically the polarisation degree is expected to increase at higher energies as the radiation from non-thermal processes is dominant fraction. So polarisation measurement in hard X-ray can yield significant insights into such processes. With the recent availability of hard X-ray optics (e.g. with upcoming NuSTAR, Astro-H missions) which can focus X-rays from 5 KeV to 80 KeV, sensitivity of X-ray detectors in hard X-ray range is expected to improve significantly. In this context we explore feasibility of a focal plane hard X-ray polarimeter based on Compton scattering having a thin plastic scatterer surrounded by cylindrical array scintillator detectors. We have carried out detailed Geant4 simulation to estimate the modulation factor for 100 % polarized beam as well as polarimetric efficiency of this configuration. We have also validated these results with a semi-analytical approach. Here we present the initial results of polarisation sensitivities of such focal plane Compton polarimeter coupled with the reflection efficiency of present era hard X-ray

  9. Multimodality hard-x-ray imaging of a chromosome with nanoscale spatial resolution

    PubMed Central

    Yan, Hanfei; Nazaretski, Evgeny; Lauer, Kenneth; Huang, Xiaojing; Wagner, Ulrich; Rau, Christoph; Yusuf, Mohammed; Robinson, Ian; Kalbfleisch, Sebastian; Li, Li; Bouet, Nathalie; Zhou, Juan; Conley, Ray; Chu, Yong S.

    2016-01-01

    We developed a scanning hard x-ray microscope using a new class of x-ray nano-focusing optic called a multilayer Laue lens and imaged a chromosome with nanoscale spatial resolution. The combination of the hard x-ray’s superior penetration power, high sensitivity to elemental composition, high spatial-resolution and quantitative analysis creates a unique tool with capabilities that other microscopy techniques cannot provide. Using this microscope, we simultaneously obtained absorption-, phase-, and fluorescence-contrast images of Pt-stained human chromosome samples. The high spatial-resolution of the microscope and its multi-modality imaging capabilities enabled us to observe the internal ultra-structures of a thick chromosome without sectioning it. PMID:26846188

  10. Development of thermally formed glass optics for astronomical hard X-ray telescopes.

    PubMed

    Craig, W; Hailey, C; Jimenez-Garate, M; Windt, D; Harrison, F; Mao, P; Christensen, F; Hussain, A

    2000-08-14

    The next major observational advance in hard X-ray/soft gamma-ray astrophysics will come with the implementation of telescopes capable of focusing 10-200 keV radiation. Focusing allows high signal-to-noise imaging and spectroscopic observations of many sources in this band for the first time. The recent development of depth-graded multilayer coatings has made the design of telescopes for this bandpass practical, however the ability to manufacture inexpensive substrates with appropriate surface quality and figure to achieve sub-arcminute performance has remained an elusive goal. In this paper, we report on new, thermally-formed glass micro-sheet optics capable of meeting the requirements of the next-generation of astronomical hard X-ray telescopes. PMID:19407863

  11. Multimodality hard-x-ray imaging of a chromosome with nanoscale spatial resolution

    NASA Astrophysics Data System (ADS)

    Yan, Hanfei; Nazaretski, Evgeny; Lauer, Kenneth; Huang, Xiaojing; Wagner, Ulrich; Rau, Christoph; Yusuf, Mohammed; Robinson, Ian; Kalbfleisch, Sebastian; Li, Li; Bouet, Nathalie; Zhou, Juan; Conley, Ray; Chu, Yong S.

    2016-02-01

    We developed a scanning hard x-ray microscope using a new class of x-ray nano-focusing optic called a multilayer Laue lens and imaged a chromosome with nanoscale spatial resolution. The combination of the hard x-ray’s superior penetration power, high sensitivity to elemental composition, high spatial-resolution and quantitative analysis creates a unique tool with capabilities that other microscopy techniques cannot provide. Using this microscope, we simultaneously obtained absorption-, phase-, and fluorescence-contrast images of Pt-stained human chromosome samples. The high spatial-resolution of the microscope and its multi-modality imaging capabilities enabled us to observe the internal ultra-structures of a thick chromosome without sectioning it.

  12. Chandra observations of the faintest hard X-ray sources in the SIX survey

    NASA Astrophysics Data System (ADS)

    Bottacini, Eugenio

    2010-09-01

    We propose 5 ks Chandra observations of each of the 4 AGN missing the NH measurement and detected in the joined Swift-INTEGRAL hard X-ray (SIX) survey, obtained merging the Swift/BAT and the INTEGRAL-IBIS surveys. The SIX survey is the deepest hard X-ray survey to date. It samples fluxes of the order ~10^-12 erg cm^-2 s^-1 above 15 keV and detects ~100 sources within 7000 deg2 sky area. Chandra observations are required to unveil the nature of this unique sample of sources. The sources are likely highly absorbed. Chandra will allow to pin-point the optical counterpart of the high energy source with a very good precision together with accurate luminosity and NH determination.

  13. Chandra observations of the faintest hard X-ray sources in the SIX survey

    NASA Astrophysics Data System (ADS)

    Bottacini, Eugenio

    2011-09-01

    We propose 5 ksec Chandra observations of each of the 20 AGN missing the NH-measurement and detected in the joined Swift-INTEGRAL hard X-ray (SIX) survey, obtained merging the Swift/BAT and the INTEGRAL-ISGRI surveys. The SIX survey is the deepest hard X-ray survey to date. It samples fluxes of the order ~10^-12 erg cm^-2 s^-1 above 15 keV and it detects 130 sources within 6200 deg^2 sky area. Chandra observations are required to unveil the nature of this unique sample of sources. The sources are likely highly absorbed. Chandra will allow to pin-point the optical counterpart of the high energy source with a very good precision together with accurate luminosity and NH determination.

  14. Balloon-Borne Hard X-Ray Spectrometer Using CdTe Detectors

    NASA Astrophysics Data System (ADS)

    Kobayashi, K.; Tsuneta, S.; Tamura, T.; Kumagai, K.; Katsukawa, Y.; Kubo, M.; Sakamoto, Y.; Kohara, N.; Yamagami, T.; Saito, Y.; Mori, K.

    2008-08-01

    Spectroscopic observation of solar flares in the hard X-ray energy range, particularly the 20 ˜ 100 keV region, is an invaluable tool for investigating the flare mechanism. This paper describes the design and performance of a balloon-borne hard X-ray spectrometer using CdTe detectors developed for solar flare observation. The instrument is a small balloon payload (gondola weight 70 kg) with sixteen 10×10×0.5 mm CdTe detectors, designed for a 1-day flight at 41 km altitude. It observes in an energy range of 20-120 keV and has an energy resolution of 3 keV at 60 keV. The second flight on 24 May 2002 succeeded in observing a class M1.1 flare.

  15. A hard x-ray prototype production exposure station at NSLS

    SciTech Connect

    Johnson, E.D.; Milne, J.C.

    1997-07-01

    Exposures conducted at the NSLS R and D beamline (X-27B) for High Aspect Ratio Precision Manufacture have proven sufficiently successful that the authors are constructing a dedicated hard x-ray exposure beamline. The new beamline (X-14B) provides an exposure field {approximately} 120 mm wide, three times larger than that of X-27B. The scanner is based on the hydraulic system from the X-27B program. It is optimized for planar exposures and takes advantage of the full 525 mm stroke available. Exposures of multiple substrates and masks will be possible, with the fixturing supporting mounting of substrate holders from other groups (ALS, APS, CAMD, and UW). The function of this beamline is to establish a hard x-ray exposure station where manufacturing scale protocols can be developed and ultimately exploited for production runs.

  16. The effect of beam-driven return current instability on solar hard X-ray bursts

    NASA Technical Reports Server (NTRS)

    Cromwell, D.; Mcquillan, P.; Brown, J. C.

    1986-01-01

    The problem of electrostatic wave generation by a return current driven by a small area electron beam during solar hard X-ray bursts is discussed. The marginal stability method is used to solve numerically the electron and ion heating equations for a prescribed beam current evolution. When ion-acoustic waves are considered, the method appears satisfactory and, following an initial phase of Coulomb resistivity in which T sub e/T sub i rise, predicts a rapid heating of substantial plasma volumes by anomalous ohmic dissipation. This hot plasma emits so much thermal bremsstrahlung that, contrary to previous expectations, the unstable beam-plasma system actually emits more hard X-rays than does the beam in the purely collisional thick target regime relevant to larger injection areas. Inclusion of ion-cyclotron waves results in ion-acoustic wave onset at lower T sub e/T sub i and a marginal stability treatment yields unphysical results.

  17. Imaging the sun in hard X-rays - Spatial and rotating modulation collimators

    NASA Technical Reports Server (NTRS)

    Campbell, Jonathan W.; Davis, John M.; Emslie, A. G.

    1991-01-01

    Several approaches to imaging hard X-rays emitted from solar flares have been proposed or are planned for the nineties including the spatial modulation collimator (SMC) and the rotating modulation collimator (RMC). A survey of current solar flare theoretical literature indicates the desirability of spatial resolutions down to 1 arcsecond, field of views greater than the full solar disk (i.e., 32 arcminutes), and temporal resolutions down to 1 second. Although the sun typically provides relatively high flux levels, the requirement for 1 second temporal resolution raises the question as to the viability of Fourier telescopes subject to the aforementioned constraints. A basic photon counting, Monte Carlo 'end-to-end' model telescope was employed using the Astronomical Image Processing System (AIPS) for image reconstruction. The resulting solar flare hard X-ray images compared against typical observations indicated that both telescopes show promise for the future.

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

    SciTech Connect

    Yamada, H.; Amano, D.; Miyade, H.

    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.

  19. Improved Contact X-Ray Microradiographic Method to Measure Mineral Density of Hard Dental Tissues.

    PubMed

    Schmuck, B D; Carey, C M

    2010-03-01

    Contact X-ray microradiography is the current gold standard for measuring mineral densities of partially demineralized tooth specimens. The X-ray sensitive film specified in the last J Res NIST publication on the subject is no longer commercially available. OBJECTIVES: Develop a new microradiographic method by identifying a commercially available film with greater than 3000 lines per millimeter resolution, which is sensitive to X rays, and develop correct film processing for X-ray microradiographic application. METHODS: A holographic film was identified as a potential replacement film. Proper exposure was determined utilizing a thick nickel plate to create test-strips. Film development was bracketed around manufacturer suggestions. Film linearity was determined with aluminum step-wedges. Microradiographs of 100 µm thick tooth sections, before and after acidic challenges, were a final test for film. Magnified images were captured with a digital microscope camera with 0.305 micrometers per pixel resolution. RESULTS: The appropriate film exposure was 30 minutes at 80 kV(p) and 3 mA with a development time of 2 minutes. Step-wedge experiments show the system to be linear in terms of pixel intensities with respect to x-ray attenuation for normalized pixel intensity values that are 10% to 90% of full scale (r(2) = 0.997) which encompasses the full exposure region of tooth tissue. Enamel sections were analyzed and show distinctive differences between erosion and demineralization. The image capture device resolution of 0.305 micrometers per pixel limits the system resolution. CONCLUSION: Use of the identified holographic film when combined with the described processing modifications has resulted in an improved X-ray microradiographic method for the measurement of mineral density of dental hard tissues. The method described can be further improved by using a higher resolution digitization system. The method is appropriate for quantitatively measuring changes in mineral

  20. The protoMIRAX hard X-ray imaging balloon experiment

    NASA Astrophysics Data System (ADS)

    Braga, João; D'Amico, Flavio; Avila, Manuel A. C.; Penacchioni, Ana V.; Rodrigo Sacahui, J.; de Santiago, Valdivino A.; Mattiello-Francisco, Fátima; Strauss, Cesar; Fialho, Márcio A. A.

    2015-08-01

    Context. The protoMIRAX hard X-ray imaging telescope is a balloon-borne experiment developed as a pathfinder for the MIRAX satellite mission. The experiment consists essentially in a coded-aperture hard X-ray (30-200 keV) imager with a square array (13 × 13) of 2 mm-thick planar CZT detectors with a total area of 169 cm2. The total, fully-coded field-of-view is 21° × 21° and the angular resolution is 1°43'. Aims: The main objective of protoMIRAX is to carry out imaging spectroscopy of selected bright sources to demonstrate the performance of a prototype of the MIRAX hard X-ray imager. In this paper we describe the protoMIRAX instrument and all the subsystems of its balloon gondola, and we show simulated results of the instrument performance. Methods: Detailed background and imaging simulations were performed for protoMIRAX balloon flights. The 3σ sensitivity for the 30-200 keV range is ~1.9 × 10-5 photons cm-2 s-1 for an integration time of 8 h at an atmospheric depth of 2.7 g cm-2 and an average zenith angle of 30°. We developed an attitude-control system for the balloon gondola and new data handling and ground systems that also include prototypes for the MIRAX satellite. Results: We present the results of Monte Carlo simulations of the camera response at balloon altitudes, showing the expected background level and the detailed sensitivity of protoMIRAX. We also present the results of imaging simulations of the Crab region. Conclusions: The results show that protoMIRAX is capable of making spectral and imaging observations of bright hard X-ray source fields. Furthermore, the balloon observations will carry out very important tests and demonstrations of MIRAX hardware and software in a near space environment.

  1. Focusing of hard x-rays to 16 manometers with a multilayer Laue lens.

    SciTech Connect

    Kang, H. C.; Yan, H.; Maser, J.; Liu, C.; Conley, R.; Macrander , A. T.; Vogt, S.; Winarski, R.; Holt, M.; Stephenson, G. B.

    2008-06-01

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

  2. InFOCuS: A Balloon-borne Hard X-ray Imaging Telescope

    NASA Technical Reports Server (NTRS)

    Krimm, Hans A.; Tueller, J.; Furuzawa, A.; Koss, M.; Kunieda, H.; Ogasaka, Y.; Okajima, T.

    2009-01-01

    InFOCuS is a new generation balloon-borne hard X-ray telescope with focusing optics and spectroscopy. After several successful flights in recent years it is being refurbished for a 2010 flight from Australia to map the hard X-ray emission from the galactic center region. in this poster, we present the status of the mirror, detectors and attitude control system. The grazing incidence optics consists of a depth-graded platinum-carbon multilayer mirror with an 8-meter focal length. It has an effective area of 78 cm(sup 2) at 30 keV. an angular resolution of 2.0 arcmin (HPD), and a field of view of 10 arcmin. The detector is a CdZnTe solid-state device capable of imaging spectroscopy. The detector is surrounded by a 3-cm thick CsI anti-coincidence shield to reduce background from particles and photons not incident along the mirror focal direction. The gondola is being reconfigured in a floating ball configuration to improve pointing control and allow the telescope to be pointed vertically. Tracking will be accomplished with a suite of on-axis and off-axis star cameras. The payload will be ready to fly from Alice Springs, Australia in Spring 2010. In this flight, InFOCuS will have the angular resolution and sensitivity to determine whether Sgr A* is the source of the hard X-rays detected by Swift/BAT and INTEGRAL and determine if there are other nearby hard X-ray sources.

  3. HEAO 1 hard X-ray observation of clusters of galaxies and intracluster magnetic fields

    NASA Technical Reports Server (NTRS)

    Rephaeli, Yoel; Gruber, D. E.

    1988-01-01

    The results of HEAO 1 hard X-ray measurements of three clusters of galaxies, Abell 401, Abell 2255, and Abell 2256 are reported. Nonthermal components were not detected above the level of 10 to the -5th photons/sq cm/s/keV. Comparison of the flux upper limits with theoretical predictions yields lower limits of about 10 to the -7th gauss on the mean value of the intracluster magnetic fields in the central regions of these clusters.

  4. A tunable wedge-shaped absorber for hard X-ray synchrotron applications.

    PubMed

    Krywka, C; Brix, M; Müller, M

    2014-07-01

    The concept of a concave aluminium wedge-shaped absorber for hard X-ray synchrotron beamlines is presented. Unlike the commonly used absorber types (fixed-thickness absorber sheets or binary exchangers of individual fixed absorbers), this concept allows a compact system, controlled with a single linear positioner, and provides a wide attenuation range as well as a precise tunability over a large energy range. Data were recorded at the Nanofocus Endstation of the MINAXS beamline, PETRA III, Hamburg, Germany. PMID:24971979

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

    PubMed

    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. PMID:23742535

  6. AGN in the Swift/BAT and INTEGRAL Hard X-ray Surveys

    NASA Technical Reports Server (NTRS)

    Beckmann, Volker; Tueller, Jack; Baumgartner, Wayne; Markwardt, Craig; Mushotzky, Richard; Skinner, Gerry

    2008-01-01

    Two hard X-ray surveys are in progress at this time. They provide a unique new window on compact objects and black holes. I will discuss how these two surveys complement each other and the potential for improved coordination that could yield significant near term results in both sensitivity and time coverage. I will pay particular attention to the discovery of faint sources including new results from the 36 month survey from Swift/Burst Alert Telescope (BAT).

  7. Fast temporal correlation between hard X-ray and ultraviolet continuum brightenings

    NASA Technical Reports Server (NTRS)

    Machado, Marcos E.; Mauas, Pablo J.

    1986-01-01

    Recent Solar Maximum Mission (SMM) observations have shown fast and simultaneous increases in hard X-rays (HXR, E25 keV) and ultraviolet continuum (UVC, lambda lambda approx. equals 1600 and 1388 A) radiation. A simple and natural explanation is given for this phenomenon to happen, which does not involve extreme conditions for energy transport processes, and confirms earlier results on the effect of XUV photoionization in the solar atmosphere.

  8. Fabrication of compound refractive lens using soft and deep X-ray lithography beamline on Indus-2

    SciTech Connect

    Dhamgaye, V. P.; Lodha, G. S.

    2012-06-05

    X-ray compound refractive lenses (CRL) have been fabricated using Soft and Deep X-ray lithography (SDXRL) beamline on Indus-2. Upto 50 parabolic lenses are fabricated in PMMA using 1X X-ray mask. The mask contains of 20 micron thick gold absorbing pattern on polyimide membrane. The lens fabrication is done by exposing 500 {mu}m thick PMMA sheets to 5-12keV X-rays from Indus-2. The fabricated CRL will be suitable for generating focused X-ray beam of Indus-2 bending magnet source.

  9. Prospects of hard X-ray polarimetry with Astrosat-CZTI

    NASA Astrophysics Data System (ADS)

    Vadawale, Santosh V.; Chattopadhyay, Tanmoy; Rao, A. R.

    2014-06-01

    Astrosat is the first Indian satellite mission dedicated for astronomical studies. It is planned for launch during 2014 and will have five instruments for multi-wavelength observations from optical to hard X-rays. Cadmium Zing Telluride Imager (CZTI) is one of the five instruments aiming for simultaneous X-ray spectroscopy and imaging in the energy range of 10 to 100 keV (along with all sky photometric capability unto 250 keV). It is based on pixilated CZT detector array with total geometric area of 10^24 cm2. It will have two-dimensional coded mask for medium resolution X-ray imaging. The CZT detector plane will be realized using CZT detector modules having integrated readout electronics. Each CZT detector module consists of 4 cm × 4 cm CZT with thickness of 5 mm which is further pixilated into 16 × 16 array of pixels. Thus each pixel has size of 2.5 mm × 2.5 mm and thickness of 5 mm. Such pixilated detector plane can in principle be used for hard X-ray polarization measurements based on the principle of Compton scattering by measuring azimuthal distribution of simultaneous events in two adjacent pixels. We have carried out detailed Geant4 simulations for estimating polarimetric capabilities of CZTI detector plane. The results indicate that events in the energy range of 100 to 250 keV, where the 5 mm thick CZT detector has significant detection efficiency, can be used for polarimetric studies. Our simulation results indicate the minimum detectable polarization (MDP) at the level of 5 % can be achieved for bright Crab like X-ray sources with exposure time of 500 ks. We also carried out preliminary experiments to verify the results from our simulations. Here we present detailed method and results of our simulations as well as preliminary results from the experimental verification of polarimetric capabilities of CZT detector modules used in Astrosat CZTI.

  10. Simbol-X: A New Generation Soft/Hard X-ray Telescope

    NASA Astrophysics Data System (ADS)

    Slane, Patrick O.; Romaine, S.; Murray, S. S.; Brissenden, R.; Elvis, M.; Gorenstein, P.; Steel, S.; O'Dell, S.; Kolodziejczak, J.; Ramsey, B.; Angelini, L.; Citterio, O.; Pareschi, G.

    2008-03-01

    Simbol-X is arguably the most powerful broad-band focusing hard (0.5-80 keV) X-ray telescope operating in the 2013 timeframe. The combination of good angular resolution, broad energy response, and efficient observing provided by a good field of view and high orbit will provide a very large increase in sensitivity in a hitherto relatively unexplored spectral region. This will enable key scientific investigations including a census of supermassive black holes in the crucial energy range in which the cosmic X-ray background peaks, measurements of the geometry and dynamics of accretion in black hole binaries, characterization of hard X-ray sources in the Galactic center, and the nature and origin of energetic particles in galaxy clusters and supernova remnants. Its single optics module contains a set of nested nickel shells coated with multilayers to boost the high-energy response and the field of view. Its focal plane detectors are a novel hybrid configuration, with thick-depletion silicon providing the low energy response, and Cadmium Telluride the high energy response. To achieve the long focal length necessary for large collecting areas at high energies, the optics and detectors are on separate high-earth-orbit formation-flying spacecrafts, 20 m apart. We describe a proposed US participation in the Simbol-X program to provide technical expertise in the area of multilayer coatings for the X-ray optics; expertise in science and the X-ray testing and calibration of the flight optics; and support as a data analysis, Guest Investigator, and archiving center. The use of the NASA DSN Goldstone station, as a complement to the Malindi tracking station,will also be provided.

  11. Exploring the spectral properties of faint hard X-ray sources with XMM-Newton

    NASA Astrophysics Data System (ADS)

    Piconcelli, E.; Cappi, M.; Bassani, L.; Fiore, F.; Di Cocco, G.; Stephen, J. B.

    2002-11-01

    We present a spectroscopic study of 41 hard X-ray sources detected serendipitously with high significance (>5sigma in the 2-10 keV band) in seven EPIC performance/verification phase observations. The large collecting area of EPIC allows us to explore the spectral properties of these faint hard X-ray sources with 2 < F2-10 < 80 x 10-14 erg cm-2 s-1 even though the length of the exposures are modest ( ~ 20 ks). Optical identifications are available for 21 sources of our sample. Using a simple power law plus Galactic absorption model we find an average value of the photon index Gamma ~ 1.6-1.7, broadly consistent with recent measurements made at similar fluxes with ASCA and with Chandra stacked spectral analyses. We find that 31 out of 41 sources are well fitted by this simple model and only eight sources require absorption in excess of the Galactic value. Interestingly enough, one third of these absorbed sources are broad line objects, though with moderate column densities. Two sources in the sample are X-ray bright optically quiet galaxies and show flat X-ray spectra. Comparing our observational results with those expected from standard synthesis models of the cosmic X-ray background (CXB) we find a fraction of unabsorbed to absorbed sources larger than predicted by theoretical models at our completeness limit of F2-10 ~ 5 x 10-14 erg cm-2 s-1. The results presented here illustrate well how wide-angle surveys performed with EPIC on board XMM-Newton allow population studies of interesting and unusual sources to be made as well as enabling constraints to be placed on some input parameters for synthesis models of the CXB.

  12. MAXI/GSC detection of a recent low-level X-ray activity and a bright hard X-ray flare from V404 Cyg

    NASA Astrophysics Data System (ADS)

    Sugimoto, J.; Negoro, H.; Kawai, N.; Tomida, H.; Nakahira, S.; Ishikawa, M.; Nakagawa, Y. E.; Mihara, T.; Sugizaki, M.; Serino, M.; Shidatsu, M.; Takagi, T.; Matsuoka, M.; Arimoto, M.; Yoshii, T.; Tachibana, Y.; Ono, Y.; Fujiwara, T.; Yoshida, A.; Sakamoto, T.; Kawakubo, Y.; Ohtsuki, H.; Tsunemi, H.; Imatani, R.; Nakajima, M.; Tanaka, K.; Masumitsu, T.; Ueda, Y.; Kawamuro, T.; Hori, T.; Tanimoto, A.; Tsuboi, Y.; Kanetou, S.; Nakamura, Y.; Sasaki, R.; Yamauchi, M.; Itoh, D.; Furuya, K.; Yamaoka, K.; Morii, M.

    2016-01-01

    Since 2015 December 23, a series of hard X-rays detections of the Galactic black hole candidate V404 Cyg (GS 2023+338) were reported with Swift-BAT (Barthelmy et al 2015 GCN #18716; ATel #8455), Fermi-GBM (Jenke at al 2015, GCN #18719; ATel #8457), and INTEGRAL-IBIS/ISGRI (Malyshev et al. ATel #8458).

  13. A Hard X-Ray View of Scorpius X-1 with INTEGRAL: Nonthermal Emission?

    NASA Astrophysics Data System (ADS)

    Di Salvo, T.; Goldoni, P.; Stella, L.; van der Klis, M.; Bazzano, A.; Burderi, L.; Farinelli, R.; Frontera, F.; Israel, G. L.; Méndez, M.; Mirabel, I. F.; Robba, N. R.; Sizun, P.; Ubertini, P.; Lewin, W. H. G.

    2006-10-01

    We present here simultaneous INTEGRAL/RXTE observations of Sco X-1 and in particular a study of the hard X-ray emission of the source and its correlation with the position in the Z track of the X-ray color-color diagram. We find that the hard X-ray (above about 30 keV) emission of Sco X-1 is dominated by a power-law component with a photon index of ~3. The flux in the power-law component slightly decreases when the source moves in the color-color diagram in the sense of increasing inferred mass accretion rate from the horizontal branch to the normal branch/flaring branch vertex. It becomes not significantly detectable in the flaring branch, where its flux has decreased by about an order of magnitude. These results present close analogies to the behavior of GX 17+2, one of the so-called Sco-like Z sources. Finally, the hard power law in the spectrum of Sco X-1 does not show any evidence of a high-energy cutoff up to 100-200 keV, strongly suggesting a nonthermal origin of this component.

  14. SENSITIVITY OF STACKED IMAGING DETECTORS TO HARD X-RAY POLARIZATION

    SciTech Connect

    Muleri, Fabio; Campana, Riccardo

    2012-06-01

    The development of multi-layer optics which allow to focus photons up to 100 keV and more promises an enormous jump in sensitivity in the hard X-ray energy band. This technology is already planned to be exploited by future missions dedicated to spectroscopy and imaging at energies >10 keV, e.g., Astro-H and NuSTAR. Nevertheless, our understanding of the hard X-ray sky would greatly benefit from carrying out contemporaneous polarimetric measurements, because the study of hard spectral tails and of polarized emission are often two complementary diagnostics of the same non-thermal and acceleration processes. At energies above a few tens of keV, the preferred technique to detect polarization involves the determination of photon directions after a Compton scattering. Many authors have asserted that stacked detectors with imaging capabilities can be exploited for this purpose. If it is possible to discriminate those events which initially interact in the first detector by Compton scattering and are subsequently absorbed by the second layer, then the direction of scattering is singled out from the hit pixels in the two detectors. In this paper, we give the first detailed discussion of the sensitivity of such a generic design to the X-ray polarization. The efficiency and the modulation factor are calculated analytically from the geometry of the instruments and then compared with the performance as derived by means of Geant4 Monte Carlo simulations.

  15. The energy relation between hard X-ray and O V emission in solar flares

    NASA Technical Reports Server (NTRS)

    Poland, A. I.; Orwig, L. E.; Mariska, J. T.; Auer, L. H.; Nakatsuka, R.

    1984-01-01

    The relationship between energy emitted in hard X-rays and the ultraviolet during the impulsive phase of solar flares provides an important diagnostic for understanding the energy flow from nonthermal to thermal. Many flares were observed from the Solar Maximum Mission satellite simultaneously in hard X-rays and the O V line at 1371 A formed at 250,000 K, providing information relevant to this problem. Previous work has shown that short time scale peaks in emission of these two types of radiation coincide in time to within 1 s. In this work the energy relation between the two types of emission is investigated and it is found that for any given flare there is a definite relation between hard X-ray and O V emissions throughout the flare, but from one flare to the next this relation varies markedly. These differences are attributed to the initial conditions in the flaring loops and some exploratory model calculations are presented to support this hypothesis.

  16. Characteristics of hard X-ray spectra of impulsive solar flares

    NASA Technical Reports Server (NTRS)

    Dulk, G. A.; Kiplinger, A. L.; Winglee, R. M.

    1992-01-01

    The typical characteristics of the hard X-ray emission of impulsive solar flares are examined. At times of hard X-ray peaks, spectra that break downward are the rule rather than the exception. The break energy is typically at about 100 keV and rarely exceed 150 keV. There is little or no dependence of spectral slopes or of the break energy on the hard X-ray fluxes. During the burst decay phases, there is a strong tendency for the spectra to evolve to either a single power law or to cross over to one that breaks upward. The break energy is usually lower after the crossover, but in about 30 percent of the cases it is higher. During the rise phase of many fast bursts, the rise in flux at high energies occurs later than that at lower energies. In most cases the high-energy flux catches up by the time of the burst peak and the lag is rarely or never observed in bursts whose rise time is more than about 10 s.

  17. The generation of rapid solar flare hard X-ray and microwave fluctuations in current sheets

    NASA Technical Reports Server (NTRS)

    Holman, Gordon D.

    1986-01-01

    The generation of rapid fluctuations, or spikes, in hard X-ray and microwave bursts via the disruption of electron heating and acceleration in current sheets is studied. It is found that 20 msec hard X-ray fluctuations can be thermally generated in a current sheet if the resistivity in the sheet is highly anomalous, the plasma density in the emitting region is relatively high, and the volume of the emitting region is greater than that of the current sheet. A specific mechanism for producing the fluctuations, involving heating in the presence of ion acoustic turbulence and a constant driving electric field, and interruption of the heating by a strong two-stream instability, is discussed. Variations upon this mechanism are also discussed. This mechanism also modulates electron acceleration, as required for the microwave spike emission. If the hard X-ray emission at energies less than approx. 1000 keV is nonthermal bremsstrahlung, the coherent modulation of electron acceleration in a large number of current sheets is required.

  18. Hard X-ray Polarimetry With Wide Band Laue Lens Telescopes

    NASA Astrophysics Data System (ADS)

    Caroli, E.

    2011-09-01

    Polarimetry is today considered a key observational parameter which can be used to help solve important scientific issues that are still open in the hard X-ray domain (above 10 keV). Therefore the ability to perform high sensitivity polarisation measurements has become a mandatory requirement for the next generation of space telescopes operating in this energy range. In particular the development of new high energy focusing optics, such as wide band Laue lenses operating from ~60 keV up to several hundred keV, with their 50-100 times better sensitivity with respect to current instrumentation, opens a real possibility to make hard X-ray polarimetry an almost standard measurement. Hard X-ray polarimetry can be performed using highly segmented focal plane detectors operated as scattering polarimeters. In this work we summarize results obtained by our group in a series of experiments with CZT/CdTe pixel detector prototypes operating as scattering polarimeters in the range between ~100-700 keV as well as Montecarlo evaluations of the achievable performance in polarisation measurements for Laue lens telescopes using focal planes based on CdTe/CZT pixel detectors.

  19. THE 70 MONTH SWIFT-BAT ALL-SKY HARD X-RAY SURVEY

    SciTech Connect

    Baumgartner, W. H.; Tueller, J.; Markwardt, C. B.; Skinner, G. K.; Barthelmy, S.; Gehrels, N.; Evans, P. A.

    2013-08-15

    We present the catalog of sources detected in 70 months of observations with the Burst Alert Telescope (BAT) hard X-ray detector on the Swift gamma-ray burst observatory. The Swift-BAT 70 month survey has detected 1171 hard X-ray sources (more than twice as many sources as the previous 22 month survey) in the 14-195 keV band down to a significance level of 4.8{sigma}, associated with 1210 counterparts. The 70 month Swift-BAT survey is the most sensitive and uniform hard X-ray all-sky survey and reaches a flux level of 1.03 Multiplication-Sign 10{sup -11} erg s{sup -1} cm{sup -2} over 50% of the sky and 1.34 Multiplication-Sign 10{sup -11} erg s{sup -1} cm{sup -2} over 90% of the sky. The majority of new sources in the 70 month survey continue to be active galactic nuclei, with over 700 in the catalog. As part of this new edition of the Swift-BAT catalog, we also make available eight-channel spectra and monthly sampled light curves for each object detected in the survey in the online journal and at the Swift-BAT 70 month Web site.

  20. Positional characteristics of meter-decameter wavelength bursts associated with hard X-ray bursts

    NASA Technical Reports Server (NTRS)

    Kundu, M. R.; Gergely, T. E.; Kane, S. R.

    1982-01-01

    Isolated and grouped type III bursts have been observed in temporal association with impulsive hard X-ray bursts in the 26-154 keV range, down to frequencies as low as 30 MHz and out to a distance of 3.1 solar radii from the disk center. The bursts occurred in regions whose electron density may have been as much as 20 times higher than that of the Newkirk-Saito model. The present observations indicate that electron acceleration/injection occurs over a region covering a wide range of magnetic field lines. It is noted that, of the two gradual hard X-ray bursts observed in association with type IV bursts, one was accompanied by a type II event, while the other was not, although both exhibited the same characteristics. It is suggested that the gradual burst associated with a type IV only involved electrons which are trapped in the plasmoid which produces the meter-decameter emission, while another fraction of the population is trapped in the low-lying loops which produce the hard X-ray and centimeter radiation.

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

    NASA Astrophysics Data System (ADS)

    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/Porb<0.1 above the period gap. In this respect, attention is given to the very low number of detected systems in any ban

  2. [O iii] λ5007 and X-Ray Properties of a Complete Sample of Hard X-Ray Selected AGNs in the Local Universe

    NASA Astrophysics Data System (ADS)

    Ueda, Y.; Hashimoto, Y.; Ichikawa, K.; Ishino, Y.; Kniazev, A. Y.; Väisänen, P.; Ricci, C.; Berney, S.; Gandhi, P.; Koss, M.; Mushotzky, R.; Terashima, Y.; Trakhtenbrot, B.; Crenshaw, M.

    2015-12-01

    We study the correlation between the [O iii] λ5007 and X-ray luminosities of local active galactic nuclei (AGNs), using a complete, hard X-ray (>10 keV) selected sample in the Swift/BAT 9-month catalog. From our optical spectroscopic observations at the South African Astronomical Observatory and the literature, a catalog of [O iii] λ5007 line flux for all 103 AGNs at Galactic latitudes of | b| \\gt 15^\\circ is compiled. Significant correlations with intrinsic X-ray luminosity ({L}{{X}}) are found for both observed ({L}[{{O} {{III}}] }) and extinction-corrected ({L}[{{O} {{III}}]}{{cor}}) luminosities, separately for X-ray unabsorbed and absorbed AGNs. We obtain the regression form of {L}[{{O} {{III}}] } \\propto \\{L}2-10\\{keV}1.18+/- 0.07 and {L}[{{O} {{III}}]}{{cor}} \\propto \\{L}2-10\\{keV}1.16+/- 0.09 from the whole sample. The absorbed AGNs with low (<0.5%) scattering fractions in soft X-rays show on average smaller {L}[{{O} {{III}}]}/{L}{{X}} and {L}[{{O} {{III}}]}{{cor}}/{L}{{X}} ratios than the other absorbed AGNs, while those in edge-on host galaxies do not. These results suggest that a significant fraction of this population is buried in tori with small opening angles. By using these {L}[{{O} {{III}}] } versus {L}{{X}} correlations, the X-ray luminosity function (LF) of local AGNs (including Compton-thick AGNs) in a standard population synthesis model gives much better agreement with the [O iii] λ5007 LF derived from the Sloan Digital Sky Survey than previously reported. This confirms that hard X-ray observations are a very powerful tool to find AGNs with high completeness.

  3. Development of a prototype nickel optic for the Constellation-X hard x-ray telescope: III

    NASA Astrophysics Data System (ADS)

    Romaine, S.; Basso, S.; Bruni, R. J.; Burkert, W.; Citterio, O.; Conti, G.; Engelhaupt, D.; Freyberg, M. J.; Ghigo, M.; Gorenstein, P.; Gubarev, M.; Hartner, G.; Mazzoleni, F.; O'Dell, S.; Pareschi, G.; Ramsey, B. D.; Speegle, C.; Spiga, D.

    2005-08-01

    The Constellation-X (Con-X) mission planned for launch in 2015, will feature an array of Hard X-ray telescopes (HXT) with a total collecting area greater than 1500 cm2 at 40 keV. Two technologies are being investigated for the optics of these telescopes, including multilayer coated Electroformed-Nickel-Replicated (ENR) shells. The attraction of the ENR process is that the resulting full-shell optics are inherently stable and offer the prospect of better angular resolution which results in lower background and higher instrument sensitivity. We are building a prototype HXT mirror module using an ENR process to fabricate the individual shells. This prototype consists of 5 shells with diameters ranging from 150 mm to 280 mm with a length of 426 mm. The innermost of these will be coated with iridium, while the remainder will be coated with graded d-spaced W/Si multilayers. Parts I and II of this work were presented at the SPIE meetings in 2003 and 2004. This paper presents a progress update and focuses on accomplishments during this past year. In particular, we will present results from full illumination X-ray tests of multilayer coated shells, taken at the MPE-Panter X-ray facility.

  4. Wavelength-tunable split-and-delay optical system for hard X-ray free-electron lasers.

    PubMed

    Osaka, Taito; Hirano, Takashi; Sano, Yasuhisa; Inubushi, Yuichi; Matsuyama, Satoshi; Tono, Kensuke; Ishikawa, Tetsuya; Yamauchi, Kazuto; Yabashi, Makina

    2016-05-01

    We developed a hard X-ray split-and-delay optical (SDO) system based on Bragg diffraction in crystal optics for generating two split pulses with a variable temporal separation. To achieve both high stability and operational flexibility, the SDO system was designed to include variable-delay and fixed-delay branches. As key optical elements, we fabricated high quality thin crystals and channel-cut crystals by applying the plasma chemical vaporization machining technique. The SDO system using Si(220) crystals covered a photon energy range of 6.5-11.5keV and a delay time range from a negative value to > 45 ps over the photon energy range (up to 220 ps at 6.5 keV). A simple alignment method for realizing a spatial overlap between the split pulses was developed. The SDO system was tested at a SPring-8 beamline in combination with a focusing system. We achieved an excellent overlap with an accuracy of 30 nm for ∼ 200 nm focused beams in both the horizontal and vertical directions. This achievement is an important progress towards the realization of time-resolved studies using multiple X-ray pulses with a time range from femtosecond to subnanosecond scales at X-ray free-electron laser facilities. PMID:27137535

  5. A Hard X-Ray Study of the Normal Star-forming Galaxy M83 with NuSTAR

    NASA Astrophysics Data System (ADS)

    Yukita, M.; Hornschemeier, A. E.; Lehmer, B. D.; Ptak, A.; Wik, D. R.; Zezas, A.; Antoniou, V.; Maccarone, T. J.; Replicon, V.; Tyler, J. B.; Venters, T.; Argo, M. K.; Bechtol, K.; Boggs, S.; Christensen, F. E.; Craig, W. W.; Hailey, C.; Harrison, F.; Krivonos, R.; Kuntz, K.; Stern, D.; Zhang, W. W.

    2016-06-01

    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\\gt 10 keV) X-ray emission of this galaxy. The nuclear region and ˜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 likely dominated by intermediate accretion state black hole binaries and neutron star low-mass X-ray binaries (Z-sources). We construct the X-ray binary luminosity function (XLF) in the NuSTAR band for an extragalactic environment for the first time. The M83 XLF has a steeper XLF than the X-ray binary 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 galactic nucleus (AGN) to be either highly obscured or to have an extremely low luminosity of ≲1038 erg s‑1 (10–30 keV), implying that it is emitting at a very low Eddington ratio. An X-ray point source that is consistent with the location of the nuclear star cluster with an X-ray luminosity of a few times 1038 erg s‑1 may be a low-luminosity AGN but is more consistent with being an X-ray binary.

  6. A Hard X-Ray Study of the Normal Star-forming Galaxy M83 with NuSTAR

    NASA Astrophysics Data System (ADS)

    Yukita, M.; Hornschemeier, A. E.; Lehmer, B. D.; Ptak, A.; Wik, D. R.; Zezas, A.; Antoniou, V.; Maccarone, T. J.; Replicon, V.; Tyler, J. B.; Venters, T.; Argo, M. K.; Bechtol, K.; Boggs, S.; Christensen, F. E.; Craig, W. W.; Hailey, C.; Harrison, F.; Krivonos, R.; Kuntz, K.; Stern, D.; Zhang, W. W.

    2016-06-01

    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\\gt 10 keV) X-ray emission of this galaxy. The nuclear region and ∼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 likely dominated by intermediate accretion state black hole binaries and neutron star low-mass X-ray binaries (Z-sources). We construct the X-ray binary luminosity function (XLF) in the NuSTAR band for an extragalactic environment for the first time. The M83 XLF has a steeper XLF than the X-ray binary 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 galactic nucleus (AGN) to be either highly obscured or to have an extremely low luminosity of ≲1038 erg s‑1 (10–30 keV), implying that it is emitting at a very low Eddington ratio. An X-ray point source that is consistent with the location of the nuclear star cluster with an X-ray luminosity of a few times 1038 erg s‑1 may be a low-luminosity AGN but is more consistent with being an X-ray binary.

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

    NASA Astrophysics Data System (ADS)

    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

  8. Starburst Galaxies: Hard X-ray spectra and contribution to the diffuse background

    NASA Technical Reports Server (NTRS)

    Gruber, Duane E.

    1993-01-01

    During the period of this grant two main tasks were performed: a determination of a selection criterion for starburst galaxies most likely to emit X-rays, and performance of a pilot study of the X-ray emission from nine such systems. Starburst galaxies may be expected to emit flat-spectrum X-ray at energies above 10 keV resulting from the various remnants of the short-lived massive stars which characterize the starburst. The investigation to determine the optimum sample resulted in a change from an X-ray selected (HEAO-2) sample to infrared selection based on the IRAS catalogue. A much broader sample thereby available for study, and selection could be limited to only the nearest objects and still obtain a reasonably large sample. A sample of 99 of the brightest infrared starburst galaxies was settled on for the X-ray survey. For a set of practical size, this was then reduced to a subset of 53, based on luminosity and nearness. X-ray emission from these objects was individually measured from the UCSD HEAO-1 all-sky survey in four energy bands between 13 keV to 160 keV. This data base consists of about 20 optical disk volumes. Net significance for the result was roughly two sigma, and a very hard spectral shape is indicated for the net spectrum of the surveyed galaxies. With the possibility of detection of the class, it was then felt worthwhile to examine fluxes from these sources in other archival data. This was performed with the HEAO-1 A2 data and the HEAO-2 (EINSTEIN) main archive and slew survey. Positive results were also obtained for the sample, but again at weak significance. With three independent measures of weak X-ray fluxes from nearby starburst galaxies, we wrote a letter to the Astrophysical Journal (enclosed) discussing these results and their likely significance, in particular, for the contribution to the cosmic diffuse x-ray background, perhaps as much as 25 percent.

  9. Experimental study of hard-X ray emission from laboratory sparks

    NASA Astrophysics Data System (ADS)

    Marisaldi, Martino; Rizzi, Rolando; Levi, Giuseppe; Malgesini, Roberto; Villa, Andrea; Mazza, Paolo; Labanti, Claudio; Fuschino, Fabio; Campana, Riccardo; Bianchini, David; Brancaccio, Rossella; Montanari, Alessandro; Patrizii, Laura

    2014-05-01

    We present the characterization of hard-X rays produced by meter-long laboratory sparks carried out at the high-voltage laboratory of RSE, Milano, Italy. Sparks are known to emit X-rays when positive and negative streamers connect, before breakdown. Numerical simulations suggest that X-rays are produced by Bremsstrahlung in air by electrons accelerated to the runaway regime in the high electric field at the streamers tip. Positive meter-long discharges are produced by a Marx generator loaded by a meter-long air gap formed by a spherical anode and a conical-shaped cathode. Maximum voltage at breakdown is about 1 MV. We investigate the production of X-rays by means of an array of scintillation detectors deployed around the cathode. Each detector is a 2'' NaI(Tl) scintillating crystal coupled to a photomultiplier tube (PMT). Each detector is battery-powered and enclosed in a metallic housing for EM shielding. Analog signal output is trasmitted to a shielded control room by means of optical fibre tranceivers, and then collected by a fast digitizer. We present the experimental setup and first results concerning detection efficiency, energy spectra, and geometrical distribution of the emission.

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

    PubMed Central

    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

  11. Hard x-ray tomographic studies of the destruction of an energetic electron ring

    NASA Astrophysics Data System (ADS)

    Wang, Y.; Gekelman, W.; Pribyl, P.

    2013-05-01

    A tomography system was designed and built at the Large Plasma Device to measure the spatial distribution of hard x-ray (100 KeV-3 MeV) emissivity. The x-rays were generated when a hot electron ring was significantly disrupted by a shear Alfvén wave. The plasma is pulsed at 1 Hz (1 shot/s). A lead shielded scintillator detector with an acceptance angle defined by a lead pinhole is mounted on a rotary gimbal and used to detect the x-rays. The system measures one chord per plasma shot using only one detector. A data plane usually consists of several hundred chords. A novel Dot by Dot Reconstruction (DDR) method is introduced to calculate the emissivity profile from the line integrated data. In the experiments, there are often physical obstructions, which make measurements at certain angles impossible. The DDR method works well even in this situation. The method was tested with simulated data, and was found to be more effective than previously published methods for the specific geometry of this experiment. The reconstructed x-ray emissivity from experimental data by this method is shown.

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

    PubMed

    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 × 10(8)/shot and 10(8 )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 3(rd) generation synchrotrons. PMID:27273170

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

    NASA Astrophysics Data System (ADS)

    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.

    2016-06-01

    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.

  14. Hard X-ray multilayer coated astronomical mirrors by e-beam deposition

    NASA Astrophysics Data System (ADS)

    Spiga, Daniele; Pareschi, Giovanni; Grisoni, Gabriele; Valsecchi, Giuseppe

    2004-10-01

    A number of X-ray astronomical missions of near future (Constellation-X, XEUS, Simbol-X) will make use of hard X-rays (10-100 keV) optics with broad-band multilayer coatings. A possible technique under development is based on an extension of the already tested replication of a coated mandrel by e-beam deposition and nickel electroforming already successfully used for the soft (0.1 - 10 keV) X-ray mirrors of the Beppo-SAX, XMM, JET-X/Swift missions. In this case graded multilayers are deposited and replicated from the mandrel replicated instead of a single layer. The roughness reduction in order to improve the coating reflectivity could be achieved by an ion assistance during the e-beam deposition. The e-beam deposition with ion assistance is a technique that allows to reach comparable (if not better) smoothness levels with respect to other methods (e.g. ion sputtering), taking the advantage of a stress mitigation between the layers and of a further improvement in reflectivity due to the low density of the e-beam evaporated Carbon, which is used as bilayer spacer. In this paper we discuss the adopted deposition technique and its implementation: we present topographic (AFM) tests and X-ray reflectivity tests performed on preliminary samples.

  15. Hard x-ray tomographic studies of the destruction of an energetic electron ring.

    PubMed

    Wang, Y; Gekelman, W; Pribyl, P

    2013-05-01

    A tomography system was designed and built at the Large Plasma Device to measure the spatial distribution of hard x-ray (100 KeV-3 MeV) emissivity. The x-rays were generated when a hot electron ring was significantly disrupted by a shear Alfvén wave. The plasma is pulsed at 1 Hz (1 shot/s). A lead shielded scintillator detector with an acceptance angle defined by a lead pinhole is mounted on a rotary gimbal and used to detect the x-rays. The system measures one chord per plasma shot using only one detector. A data plane usually consists of several hundred chords. A novel Dot by Dot Reconstruction (DDR) method is introduced to calculate the emissivity profile from the line integrated data. In the experiments, there are often physical obstructions, which make measurements at certain angles impossible. The DDR method works well even in this situation. The method was tested with simulated data, and was found to be more effective than previously published methods for the specific geometry of this experiment. The reconstructed x-ray emissivity from experimental data by this method is shown. PMID:23742547

  16. The Swift/BAT Hard X-ray Transient Monitor: A Status Report

    NASA Astrophysics Data System (ADS)

    Krimm, Hans A.; Bloom, J. S.; Markwardt, C.; Miler-Jones, J.; Gehrels, N.; Kennea, J. A.; Holland, S.; Sivakoff, G. R.; Swift/BAT Team

    2013-04-01

    The Swift/Burst Alert Telescope (BAT) hard X-ray transient monitor provides near real-time coverage of the X-ray sky in the energy range 15-50 keV. This monitor was first announced at the 2006 HEAD meeting. Seven years later, it continues to operate and provides near real-time light curves of more than 900 astrophysical sources. The BAT observes ~75% of the sky each day with a 3-sigma detection sensitivity of 7 mCrab for a full-day observation and a time resolution as fine as 64 seconds. The three main purposes of the monitor are (1) the discovery of new transient X-ray sources, (2) the detection of outbursts or other changes in the flux of known X-ray sources, and (3) the generation of archival light curves spanning nearly seven years. The primary interface for the BAT transient monitor is a public web page. Since February 2005, 223 sources have been detected in the monitor, 142 of them persistent and 81 detected only in outburst. From 2006-2013, fourteen new sources have been discovered by the BAT transient monitor. We will describe the methodology of the transient monitor, present a summary of its statistics, and discuss the detection of known and newly discovered sources.

  17. The Swift/BAT Hard X-ray Transient Monitor: A Status Report

    NASA Astrophysics Data System (ADS)

    Krimm, Hans A.; Swift/BAT Team

    2011-09-01

    The Swift/Burst Alert Telescope (BAT) hard X-ray transient monitor provides near real-time coverage of the X-ray sky in the energy range 15-50 keV. This monitor was first announced at the 2006 HEAD meeting. Five years later, it continues to operate and provides near real-time light curves of more than 900 astrophysical sources. The BAT observes 75% of the sky each day with a 3-sigma detection sensitivity of 7 mCrab for a full-day observation and a time resolution as fine as 64 seconds. The three main purposes of the monitor are (1) the discovery of new transient X-ray sources, (2) the detection of outbursts or other changes in the flux of known X-ray sources, and (3) the generation of archival light curves spanning nearly seven years. The primary interface for the BAT transient monitor is a public web page. Since February 2005, 172 sources have been detected in the monitor, 89 of them persistent and 83 detected only in outburst. From 2006-2011, nine new sources have been discovered by the BAT transient monitor. We will describe the methodology of the transient monitor, present a summary of its statistics, and discuss the detection of known and newly discovered sources.

  18. Hard x-ray tomographic studies of the destruction of an energetic electron ring

    SciTech Connect

    Wang, Y.; Gekelman, W.; Pribyl, P.

    2013-05-15

    A tomography system was designed and built at the Large Plasma Device to measure the spatial distribution of hard x-ray (100 KeV-3 MeV) emissivity. The x-rays were generated when a hot electron ring was significantly disrupted by a shear Alfven wave. The plasma is pulsed at 1 Hz (1 shot/s). A lead shielded scintillator detector with an acceptance angle defined by a lead pinhole is mounted on a rotary gimbal and used to detect the x-rays. The system measures one chord per plasma shot using only one detector. A data plane usually consists of several hundred chords. A novel Dot by Dot Reconstruction (DDR) method is introduced to calculate the emissivity profile from the line integrated data. In the experiments, there are often physical obstructions, which make measurements at certain angles impossible. The DDR method works well even in this situation. The method was tested with simulated data, and was found to be more effective than previously published methods for the specific geometry of this experiment. The reconstructed x-ray emissivity from experimental data by this method is shown.

  19. PLEIADES: High Peak Brightness, Subpicosecond Thomson Hard-X-ray source

    SciTech Connect

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

    2003-12-15

    The Picosecond Laser-Electron Inter-Action for the Dynamic Evaluation of Structures (PLEIADES) facility, is a unique, novel, tunable (10-200 keV), ultrafast (ps-fs), hard x-ray source that greatly extends the parameter range reached by existing 3rd generation sources, both in terms of x-ray energy range, pulse duration, and peak brightness at high energies. First light was observed at 70 keV early in 2003, and the experimental data agrees with 3D codes developed at LLNL. The x-rays are generated by the interaction of a 50 fs Fourier-transform-limited laser pulse produced by the TW-class FALCON CPA laser and a highly focused, relativistic (20-100 MeV), high brightness (1 nC, 0.3-5 ps, 5 mm.mrad, 0.2% energy spread) photo-electron bunch. The resulting x-ray brightness is expected to exceed 10{sup 20} ph/mm{sup 2}/s/mrad{sup 2}/0.1% BW. The beam is well-collimated (10 mrad divergence over the full spectrum, 1 mrad for a single color), and the source is a unique tool for time-resolved dynamic measurements in matter, including high-Z materials.

  20. X-Ray Ccds for Space Applications: Calibration, Radiation Hardness, and Use for Measuring the Spectrum of the Cosmic X-Ray Background

    NASA Astrophysics Data System (ADS)

    Gendreau, Keith Charles

    1995-01-01

    This thesis has two distinct components. One concerns the physics of the high energy resolution X-ray charge coupled devices (CCD) detectors used to measure the cosmic X-ray background (XRB) spectrum. The other involves the measurements and analysis of the XRB spectrum and instrumental background with these detectors on board the advanced satellite for cosmology and astrophysics (ASCA). The XRB has a soft component and a hard component divided at ~2 keV. The hard component is extremely isotropic, suggesting a cosmological origin. The soft component is extremely anisotropic. A galactic component most likely dominates the soft band with X-ray line emission due to a hot plasma surrounding the solar system. ASCA is one of the first of a class of missions designed to overlap the hard and soft X-ray bands. The X-ray CCD's energy resolution allows us to spectrally separate the galactic and cosmological components. Also, the resolution offers the ability to test several specific cosmological models which would make up the XRB. I have concentrated on models for the XRB origin which include active galactic nuclei (AGN) as principal components. I use ASCA data to put spectral constraints on the AGN synthesis model for the XRB. The instrumental portion of this thesis concerns the development and calibration of the X-ray CCDs. I designed, built and operated an X-ray calibration facility for these detectors. It makes use of a reflection grating spectrometer to measure absolute detection efficiency, characteristic absorption edge strengths, and spectral redistribution in the CCD response function. Part of my thesis research includes a study of radiation damage mechanisms in CCDs. This work revealed radiation damage-induced degradation in the spectral response to X-rays. It also uncovered systematic effects which affect both data analysis and CCD design. I have developed a model involving trap energy levels in the CCD band gap structure. These traps reduce the efficiency in which

  1. Hard X-ray Imaging Microscopy using X-ray Guide Tube as Beam Condenser for Field Illumination

    NASA Astrophysics Data System (ADS)

    Suzuki, Yoshio; Takeuchi, Akihisa; Uesugi, Kentaro; Terada, Yasuko; Nakazawa, Hiromoto; Ohzawa, Sumito; Aoyama, Tomoki; Nii, Hajime; Handa, Katsumi

    2013-10-01

    An optical system for illumination of object in x-ray imaging microscopy is developed. The optical system is a beam condenser consisting of a single-bounce conical-shape mono-capillary (x-ray guide tube: XGT) made of Pyrex glass. The XGT condenser was tested at the beam line 47XU of SPring-8 using a Fresnel zone plate as an objective lens. Comparing with the microscope without beam condenser, the flux density is improved by a factor of 12-20 in the x-ray energy range of 6-8 keV. Test patterns with a 50 nm-structure are clearly resolved at 8 keV with an exposure time less than 1 s.

  2. Diffractive imaging at large Fresnel number: Challenge of dynamic mesoscale imaging with hard x rays

    NASA Astrophysics Data System (ADS)

    Barber, John L.; Barnes, Cris W.; Sandberg, Richard L.; Sheffield, Richard L.

    2014-05-01

    Real materials have structure at both the atomic or crystalline scale as well as at interfaces and defects at the larger scale of grains. There is a need for the study of materials at the "mesoscale," the scale at which subgranular physical processes and intergranular organization couple to determine microstructure, crucially impacting constitutive response at the engineering macroscale. Diffractive imaging using photons that can penetrate multiple grains of material would be a transformative technique for the study of the performance of materials in dynamic extremes. Thicker samples imply higher energy photons of shorter wavelength, and imaging of multiple grains implies bigger spot sizes. Such imaging requires the use of future planned and proposed hard x-ray free electron lasers (such as the European XFEL) to provide both the spatial coherence transverse to the large spots and the peak brilliance to provide the short illumination times. The result is that the Fresnel number of the system becomes large and is no longer in the Fraunhofer far-field limit. The interrelated issues of diffractive imaging at large Fresnel number are analyzed, including proof that diffractive imaging is possible in this limit and estimates of the signal-to-noise possible. In addition, derivation of the heating rates for brilliant pulses of x rays are presented. The potential and limitations on multiple dynamic images are derived. This paper will present a study of x-ray interactions with materials in this new regime of spatially coherent but relatively large mesoscale spots at very hard energies. It should provide the theory and design background for the experiments and facilities required to control materials in extreme environments, in particular for the next generation of very-hard-x-ray free electron lasers.

  3. Modelling a C-type flare observed in microwaves and hard X-rays

    NASA Technical Reports Server (NTRS)

    Schmahl, E. J.; Kundu, M. R.; Dennis, Brian R.

    1988-01-01

    Using the very large array (VLA) at 6 and 20 cm wavelength and the hard X-ray burst spectrometer on the Solar Maximum Mission, a two-ribbon flare was observed from the onset phase through the maximum and decline on November 14, 1981. Because of the extensive size of the microwave source and the gradual variations in hard X-rays whose spectrum becomes progressively flatter with time, the flare is classified as a C-type flare. Considering the hardening of the X-ray spectrum and its non-impulsive nature, a coronal trap model was invoked for the energetic electrons. The microwave emission is easily accounted for by gyrosynchronous radiation from mildly relativistic electrons. It was found that the source must be optically thick at 20 cm during the maximum phase, but as the source evolved toward an optically thin regime, the intensity decreased while the degree of circular polarization increased. In an initial homogeneous model, we found that the computed microwave spectrum was too narrow to match the patrol spectrum from 606 to 15400 MHz. In the model, the magnetic field consists of a dipolar arcade bridging the H alpha ribbons, and extending to heights of order 40,000 to 50,000 km. The variation of the magnetic field strength from footpoints to apex causes the gyrosynchrotron spectrum to be broader. Preliminary conclusions regarding the electron distributions producing the hard X-rays and the microwaves, and the suitability of this model for C-type flares is presented.

  4. The HEXIT-SAT and SIMBOL-X Hard X-ray missions

    NASA Astrophysics Data System (ADS)

    Pareschi, G.; HEXIT-SAT and SIMBOL-X Collaborations

    HEXIT-SAT and SIMBOL-X are two astronomy mission concepts based on hard X-ray (E ge 10 keV) focusing optics, with several Italian researchers involved in the design and definition of both satellites. HEXIT-SAT is based on 4 optics modules with 8 m focal lenghth, each formed by a number of confocal multilayer-coated Wolter I shells, the maximum diameter being 35 cm. Due to their broad-band reflection response, multilayer mirrors allow us to focus X-ray photons with energies beyond 10 keV up to about 100 keV, a region where just direct-view detectors have been operated so far. The SIMBOL-X project instead relies on a single-module optics with 60 cm diameter, and it is characterized by a very large focal length (30 m), achieved by means of two separate spacecrafts (one for the mirror module, the other for the detector unit) in a formation-flight configuration. At the moment the reflecting coating assumed for the mirrors is a Pt single layer film that, due to the very small reflection angles involved, is able to guarantee a high effective area for hard X-rays up to 50 keV. The use of multilayer mirrors to further extend the reflection band is currently being considered. HEXIT-SAT and SIMBOL-X are both characterized by an unprecedented flux sensitivity (with a gain of several hundreds compared to the hard X-ray missions already flown) and a much better angular resolution. In this paper a short review of the main features of both missions is reported.

  5. The populations of hard X-ray sources in our Galaxy

    NASA Astrophysics Data System (ADS)

    Tomsick, John

    In this program, we will analyze follow-up observations that were awarded to us for seven hard X-ray emitting sources located in the Galactic Plane, five of which have yet to be classified. This data set represents over 300 ks worth of exposure time with Suzaku and XMM-Newton. Our Suzaku (cycle 6) observation will cover a complete orbital cycle of the supergiant fast X-ray transient (SFXT) IGR J16479-4514. This will help us discriminate between the different models that have been proposed to explain the sporadic and highly-variable emission from this newly-recognized class of objects. The five unclassified sources are located towards the Scutum Arm and are likely to be high- mass X-ray binaries. Our recently-performed XMM-Newton (cycle 9) observations will allow us to identify and analyze the likely optical/infrared counterpart, while the X-ray spectral and timing analyses will clarify the nature of the compact object. Our XMM- Newton (cycle 10) observation of a young supernova remnant named IGR J17448-3232 will provide a clearer image of this diffuse object permitting a better description of its morphology as well as allowing us to assess for the first time the spectral variability across the structure: both of which are necessary to constrain high-energy particle acceleration mechanisms. In addition to publications on these specific observations, we will complete a catalog of hard X-ray sources that we can use to perform statistical analyses. Hence, following the study of individual objects, we widen our scope to view the global characteristics of the different hard X-ray emitting source populations in our Galaxy. The analysis and interpretation of these carefully-selected data sets will be of value to a wide community: from high-energy astronomers to theorists in stellar and Galactic evolution. The end result of this program will be a better understanding of the accretion physics, radiation processes, and evolution of compact stellar objects.

  6. Comparison of solar hard X-ray and UV line and continuum bursts with high time resolution

    NASA Technical Reports Server (NTRS)

    Orwig, L. E.; Woodgate, B. E.

    1986-01-01

    A comparison of data sets from the UV Spectrometer and Polarimeter and Hard X-ray Burst Spectrometer instruments on SMM has established the close relationship of the impulsive phase hard X-ray and UV continuum and OV line emissions, lending support to the notion that they have a similar origin low in the solar atmosphere. These results severely constrain models that attempt to explain impulsive phase hard X-rays and UV emission; alternative processes of impulsive-phase UV continuum production should accordingly be considered. Attention is given to an electron beam 'hole boring' mechanism and a photoionization radiation transport mechanism.

  7. Development of position sensitive scintillation counter for balloon-borne hard x-ray telescope

    NASA Astrophysics Data System (ADS)

    Tamura, Keisuke; Kunieda, Hideyo; Ogasaka, Yasushi; Furuzawa, Akihiro; Shibata, Ryo; Nakamura, Tomokazu; Ohnishi, Katsuhiko; Kanou, Yasufumi; Miyata, Emi; Tsunemi, Hiroshi

    2006-06-01

    We have been developing position sensitive scintillation counter as focal plane detector of hard X-ray telescope onboard a balloon borne experiment. This detector consists NaI(TI) scintillator and position sensitive photo-multiplier tube. Focal plane detector has to have high efficiency in hard X-ray region, enough position resolution and detection area. 3mm thickness of NaI(TI) scintillator can achieve almost 100% efficiency below 80 keV. We measured position resolved energy and position resolution in synchrotron radiation facility SPring-8 BL20B2. Position resolution of 2.4mm at 60keV is about half of plate scale of half power diameter of X-ray telescope. The detector has 6 cm diameter window and it corresponds to 25 arcmin field of view, and it is enough lager than the that of telescope, which is 12 arcmin in FWHM. Balloon borne experiment for observation of the background was performed on May 24, 2005 from Sanriku balloon center. We could obtain background data for 3 hours at altitude of 40 km.

  8. Evaluation of a `CMOS' Imager for a Shadow Mask Hard X-Ray Telescope

    NASA Astrophysics Data System (ADS)

    Desai, U. D.; Orwig, L. E.

    2002-05-01

    We have developed a hard x-ray coder that provides high angular resolution imaging capability using a coarse position-sensitive image plane detector. The coder consists of two Fresnel zone plates (FZP). Two such FZP's generate Moiré fringe patterns whose frequency and orientation define the arrival direction of a beam with respect to the telescope axis. The image plane detector needs to resolve the Moiré fringe pattern. Pixellated detectors can be used as an image plane detector. The recently available `CMOS' imager could provide a very low power large area image plane detector for hard x-rays. We have looked into a unit made by Rad-Icon Imaging Corp. The Shad-o-Box 1024 x-ray camera is a high resolution 1024x1024 pixel detector of 50x50 mm area. It is a very low power, stand-alone camera. We present some preliminary results of our evaluation of such a camera.

  9. HARD X-RAY FLUX UPPER LIMITS OF CENTRAL COMPACT OBJECTS IN SUPERNOVA REMNANTS

    SciTech Connect

    Erdeve, I.; Kalemci, E.; Alpar, M. A.

    2009-05-10

    We searched for hard X-ray (20-300 keV) emission from nine central compact objects (CCOs) 1E 1207.4-5209, 1WGA J1713-3949, J082157.5-430017, J085201.4-461753, J160103.1-513353, J1613483-5055, J181852.0-150213, J185238.6+004020, and J232327.9+584843 with the International Gamma-Ray Astrophysics Laboratory observatory. We applied spectral imaging analysis and did not detect any of the sources with luminosity upper limits in the range of 10{sup 33}-10{sup 34} erg s{sup -1} in the 20-75 keV band. For nearby CCOs (less than 4 kpc), the upper-limit luminosities are an order of magnitude lower than the measured persistent hard X-ray luminosities of anomalous X-ray pulsars. This may indicate that the CCOs are low magnetic field systems with fallback disks around them.

  10. Hard x-ray transmission crystal spectrometer at the OMEGA-EP laser facility

    SciTech Connect

    Seely, J. F.; Szabo, C. I.; Feldman, U.; Hudson, L. T.; Henins, A.; Audebert, P.; Brambrink, E.

    2010-10-15

    The transmission crystal spectrometer (TCS) is approved for taking data at the OMEGA-EP laser facility since 2009 and will be available for the OMEGA target chamber in 2010. TCS utilizes a Cauchois type cylindrically bent transmission crystal geometry with a source to crystal distance of 600 mm. Spectral images are recorded by image plates in four positions, one IP on the Rowland circle and three others at 200, 400, and 600 mm beyond the Rowland circle. An earlier version of TCS was used at LULI on experiments that determined the x-ray source size from spectral line broadening on one IP positioned behind the Rowland circle. TCS has recorded numerous backlighter spectra at EP for point projection radiography and for source size measurements. Hard x-ray source size can be determined from the source broadening of both K shell emission lines and from K absorption edges in the bremsstrahlung continuum, the latter being a new way to measure the spatial extent of the hard x-ray bremsstrahlung continuum.

  11. The optics system of the New Hard X-ray Mission: design and development

    NASA Astrophysics Data System (ADS)

    Basso, Stefano; Pareschi, Giovanni; Citterio, Oberto; Spiga, Daniele; Tagliaferri, Gianpiero; Civitani, Marta; Raimondi, Lorenzo; Sironi, Giorgia; Cotroneo, Vincenzo; Negri, Barbara; Parodi, Giancarlo; Martelli, Francesco; Borghi, Giuseppe; Orlandi, Alessandro; Vernani, Dervis; Valsecchi, Giuseppe; Binda, Riccardo; Romaine, Suzanne; Gorenstein, Paul; Attinà, Primo

    2010-07-01

    The New Hard X-ray Mission (NHXM) project will be operated by 2016 and is currently undergoing the Phase B study. 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 optics of the mission, based on thin replicated Ni mirror shells.

  12. SCO X-1: Origin of the radio and hard X-ray emissions

    NASA Technical Reports Server (NTRS)

    Ramaty, R.; Cheng, C. C.; Tsuruta, S.

    1973-01-01

    The consequences of models for the central radio source and the hard X-ray ( 30 keV) emitting region in Sco X-1 are examined. It was found that the radio emission could result from noncoherent synchrotron radiation and that the X-rays may be produced by bremsstrahlung. It is shown that both mechanisms require a mass outflow from Sco X-1. The radio source is located at r approximately 3x10 to the 12th power cm from the center of the star, and its linear dimensions do not exceed 3x10 to the 13th power cm. The magnetic field in the radio source is on the order of 1 gauss. If the hard X-rays are produced by thermal bremsstrahlung, their source is located at 10 to the 9th power approximately r approximately 5x10 to the 9th power cm, the temperature is 2x10 to the 9th power K, and the emission measure is 2x10 to the 56th power/cu cm. This hot plasma loses energy inward by conduction and outward by supersonic expansion. The rates of energy loss for both processes are about 10 to the 36th power erg/s, comparable to the total luminosity of Sco X-1.

  13. Unification of Low Luminosity AGN and Hard State X-ray Binaries

    NASA Astrophysics Data System (ADS)

    Connolly, S.

    2015-09-01

    We present X-ray spectral variability of four low accretion rate and low luminosity AGN (LLAGN)- M81, NGC 1097, NGC 1052 and NGC 3998 - as observed by Swift and RXTE. All four objects were selected due to having spectra which hardened with increasing count rate, converse to the 'softer when brighter' behaviour normally observed in AGN with higher accretion rates. The spectra were summed in flux bins and fitted with a variety of models. A simple absorbed power law model was found to fit the spectra of M81, NGC 1097 and NGC 3998 well, whilst NGC 1052 required a partially covered power law model. In all four cases, the most likely cause of spectral variability is found to be hardening of the photon index of the power law component with increasing luminosity. Such a correlation has been seen previously within samples of low accretion rate AGN but in only one case has it been seen within observations of a single AGN. Here we show that such behaviour may be very common in LLAGN. A similar anticorrelation is found in X-ray binary systems in the 'hard state', at low accretion rates similar to those of the LLAGN discussed here. Our observations thus imply that LLAGN are the active galaxy equivalent of hard state X-ray binaries.

  14. Hard x-ray transmission crystal spectrometer at the OMEGA-EP laser facilitya)

    NASA Astrophysics Data System (ADS)

    Seely, J. F.; Szabo, C. I.; Feldman, U.; Hudson, L. T.; Henins, A.; Audebert, P.; Brambrink, E.

    2010-10-01

    The transmission crystal spectrometer (TCS) is approved for taking data at the OMEGA-EP laser facility since 2009 and will be available for the OMEGA target chamber in 2010. TCS utilizes a Cauchois type cylindrically bent transmission crystal geometry with a source to crystal distance of 600 mm. Spectral images are recorded by image plates in four positions, one IP on the Rowland circle and three others at 200, 400, and 600 mm beyond the Rowland circle. An earlier version of TCS was used at LULI on experiments that determined the x-ray source size from spectral line broadening on one IP positioned behind the Rowland circle. TCS has recorded numerous backlighter spectra at EP for point projection radiography and for source size measurements. Hard x-ray source size can be determined from the source broadening of both K shell emission lines and from K absorption edges in the bremsstrahlung continuum, the latter being a new way to measure the spatial extent of the hard x-ray bremsstrahlung continuum.

  15. Hard x-ray transmission crystal spectrometer at the OMEGA-EP laser facility.

    PubMed

    Seely, J F; Szabo, C I; Feldman, U; Hudson, L T; Henins, A; Audebert, P; Brambrink, E

    2010-10-01

    The transmission crystal spectrometer (TCS) is approved for taking data at the OMEGA-EP laser facility since 2009 and will be available for the OMEGA target chamber in 2010. TCS utilizes a Cauchois type cylindrically bent transmission crystal geometry with a source to crystal distance of 600 mm. Spectral images are recorded by image plates in four positions, one IP on the Rowland circle and three others at 200, 400, and 600 mm beyond the Rowland circle. An earlier version of TCS was used at LULI on experiments that determined the x-ray source size from spectral line broadening on one IP positioned behind the Rowland circle. TCS has recorded numerous backlighter spectra at EP for point projection radiography and for source size measurements. Hard x-ray source size can be determined from the source broadening of both K shell emission lines and from K absorption edges in the bremsstrahlung continuum, the latter being a new way to measure the spatial extent of the hard x-ray bremsstrahlung continuum. PMID:21034000

  16. FIVE NEW INTEGRAL UNIDENTIFIED HARD X-RAY SOURCES UNCOVERED BY CHANDRA

    SciTech Connect

    Fiocchi, M.; Bazzano, A.; Ubertini, P.; Capitanio, F.

    2010-09-10

    The IBIS imager on board INTEGRAL, with a sensitivity better than a milliCrab in deep observations and a point-source location accuracy on the order of few arcminutes, has thus far localized 723 hard X-ray sources in the 17-100 keV energy band, of which about 1/3 are still unclassified. The aim of this paper is to provide subarcsecond localizations of the unidentified sources, necessary to pinpoint the optical and/or infrared (IR) counterpart of those objects whose nature is so far unknown. Cross-correlation between the new IBIS sources published in the fourth INTEGRAL/IBIS Survey catalog and the Chandra/ACIS data archive resulted in a sample of five previously unidentified objects. We present here the results of Chandra X-ray Observatory observations of these five hard X-ray sources discovered by the INTEGRAL satellite. We associated IGR J10447-6027 with IR source 2MASS J10445192-6025115, IGR J16377-6423 with the cluster CIZA J1638.2-6420, IGR J14193-6048 with the pulsar with nebula PSR J1420-6048, and IGR J12562+2554 with the quasar SDSS J125610.42+260103.5. We suggest that the counterpart of IGR J12288+0052 may be an active galactic nucleus/quasi-stellar object type 2 at a confidence level of 90%.

  17. Imaging of cochlear tissue with a grating interferometer and hard X-rays

    SciTech Connect

    Richter, Claus-Peter; Shintani-Smith, Stephanie; Fishman, Andrew; David, Christian; Robinson, Ian; Rau, Christoph

    2010-01-28

    This article addresses an important current development in medical and biological imaging: the possibility of imaging soft tissue at resolutions in the micron range using hard X-rays. Challenging environments, including the cochlea, require the imaging of soft tissue structure surrounded by bone. We demonstrate that cochlear soft tissue structures can be imaged with hard X-ray phase contrast. Furthermore, we show that only a thin slice of the tissue is required to introduce a large phase shift. It is likely that the phase contrast image of the soft tissue structures is sufficient to image the structures even if surrounded by bone. For the present set of experiments, structures with low-absorption contrast have been visualized using in-line phase contrast imaging and a grating interferometer. The experiments have been performed at the Advanced Photon Source at Argonne National Laboratories, a third generation source of synchrotron radiation. The source provides highly coherent X-ray radiation with high-photon flux (>10{sup 12} photons/s) at high-photon energies (5-70 keV). Radiographic and light microscopy images of the gerbil cochlear slice samples were compared. It has been determined that a 20-{micro}m thick tissue slice induces a phase shift between 1/3{pi} and 2/3{pi}.

  18. Hard X-ray spectra of neutron stars and black hole candidates

    NASA Technical Reports Server (NTRS)

    Durouchoux, P.; Mahoney, W.; Clenet, Y.; Ling, J.; Wallyn, P.; Wheaton, W.; Corbet, S.; Chapuis, C.

    1997-01-01

    The hard X-ray behavior of several X-ray binary systems containing a neutron star or a black hole candidate is analyzed in an attempt to determine the specific signature of these categories of compact objects. Limiting the consideration to two subclasses of neutron stars, Atoll sources and non-pulsating Z sources, it appears that only the Atoll sources have a spectral behavior similar to black holes. It is proposed that Atoll sources are weakly magnetized neutron stars, whereas Z sources are small radius moderate magnetized neutron stars. Large magnetic fields funnel the accreting matter, thus preventing spherical accretion and free fall if the neutron star radius is smaller than the last stable accreting orbit. Weak magnetic fields do not have this effect, and blackbody soft photons from the stellar surface are upscattered on the relativistic infalling matter, leading to excess hard X-rays. This excess is visible in two of the observed Atoll sources and in the spectrum of a black hole candidate. In the case of a Z source, a lack of photons was remarked, providing a possible signature to distinguish between these classes of objects.

  19. SuperHERO: The Next Generation Hard X-ray HEROES Telescope

    NASA Technical Reports Server (NTRS)

    Gaskin, Jessica A.; Christe, Steven D.; Wilson-Hodge, Colleen; Shih, Albert Y. M.; Ramsey, Brian D.; Tennant, Allyn F.; Swartz, Douglas A.

    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.

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

    NASA Technical Reports Server (NTRS)

    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.; Wilson, Matthew D.

    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.

  1. PoGOLite - a circumpolar balloon-borne mission for hard X-ray polarimetry

    NASA Astrophysics Data System (ADS)

    Pearce, Mark

    Mark Pearce For the PoGOLite Collaboration. KTH Royal Institute of Technology, Dept. of Physics, Stockholm, Sweden. pearce@kth.se Abstract Emission processes in astrophysical systems can yield polarised hard X-rays. The orientation of the polarisation plane is a powerful probe of the physical environment around compact astrophysical sources. Despite the wealth of sources accessible to polarisation measurements, and the importance of these measurements, it is 40 years since the last dedicated mission for X-ray polarimetry of point sources. PoGOLite is a balloon-borne hard X-ray polarimeter operating in the 25-100 keV energy band. Polarisation is determined using coincident Compton scattering and photo-absorption in a segmented array of plastic scintillators surrounded by a BGO anticoincidence system and a polyethylene neutron shield. PoGOLite was launched from the Esrange Space Center on July 12th 2013 with the Crab nebula and pulsar as primary observation targets. The mission was terminated on July 25th after an almost complete circumpolar flight. The PoGOLite mission was conducted as a collaboration between Swedish, Japanese, Russian and US scientific teams. The PoGOLite circumpolar mission will be reviewed and the outcome of the 2013 flight discussed.

  2. Long-Term Variability of AGN at Hard X-Rays

    NASA Technical Reports Server (NTRS)

    Soldi, S.; Beckmann, V.; Baumgartner W. H.; Ponti, G.; Shrader, C. R.; Lubinski, P.; Krimm, H. A.; Mattana, F.; Tueller, J.

    2013-01-01

    Variability at all observed wavelengths is a distinctive property of active galactic nuclei (AGN). Hard X-rays provide us with a view of the innermost regions of AGN, mostly unbiased by absorption along the line of sight. Characterizing the intrinsic hard X-ray variability of a large AGN sample and comparing it to the results obtained at lower X-ray energies can significantly contribute to our understanding of the mechanisms underlying the high-energy radiation. Methods. Swift/BAT provides us with the unique opportunity to follow, on time scales of days to years and with a regular sampling, the 14-195 keV emission of the largest AGN sample available up to date for this kind of investigation. As a continuation of an early work on the first 9 months of BAT data, we study the amplitude of the variations, and their dependence on sub-class and on energy, for a sample of 110 radio quiet and radio loud AGN selected from the BAT 58-month survey. About 80 of the AGN in the sample are found to exhibit significant variability on months to years time scales, radio loud sources being the most variable. The amplitude of the variations and their energy dependence are incompatible with variability being driven at hard X-rays by changes of the absorption column density. In general, the variations in the 14-24 and 35-100 keV bands are well correlated, suggesting a common origin of the variability across the BAT energy band. However, radio quiet AGN display on average 10 larger variations at 14-24 keV than at 35-100 keV and a softer-when-brighter behavior for most of the Seyfert galaxies with detectable spectral variability on month time scale. In addition, sources with harder spectra are found to be more variable than softer ones. These properties are generally consistent with a variable power law continuum, in flux and shape, pivoting at energies 50 keV, to which a constant reflection component is superposed. When the same time scales are considered, the timing properties of AGN at

  3. Long-term variability of AGN at hard X-rays

    NASA Astrophysics Data System (ADS)

    Soldi, S.; Beckmann, V.; Baumgartner, W. H.; Ponti, G.; Shrader, C. R.; Lubiński, P.; Krimm, H. A.; Mattana, F.; Tueller, J.

    2014-03-01

    Aims: Variability at all observed wavelengths is a distinctive property of active galactic nuclei (AGN). Hard X-rays provide us with a view of the innermost regions of AGN, mostly unbiased by absorption along the line of sight. Characterizing the intrinsic hard X-ray variability of a large AGN sample and comparing it to the results obtained at lower X-ray energies can significantly contribute to our understanding of the mechanisms underlying the high-energy radiation. Methods: Swift/BAT provides us with the unique opportunity to follow, on time scales of days to years and with regular sampling, the 14-195 keV emission of the largest AGN sample available up to date for this kind of investigation. As a continuation of an early work using the first 9 months of BAT data, we study the amplitude of the variations and their dependence on subclass and on energy, for a sample of 110 radio quiet and radio loud AGN selected from the BAT 58-month survey. Results: About 80% of the AGN in the sample are found to exhibit significant variability on month-to-year time scales. In particular, radio loud sources are the most variable, and Seyfert 1.5-2 galaxies are slightly more variable than Seyfert 1, while absorbed and unabsorbed objects show similar timing properties. The amplitude of the variations and their energy dependence are incompatible with variability being driven at hard X-rays by changes in the absorption column density. In general, the variations in the 14-24 and 35-100 keV bands are correlated well, suggesting a common origin to the variability across the BAT energy band. However, radio quiet AGN display on average 10% larger variations at 14-24 keV than at 35-100 keV, and a softer-when-brighter behavior for most of the Seyfert galaxies with detectable spectral variability on a time scale of a month. In addition, sources with harder spectra are found to be more variable than softer ones, unlike what it is observed below 10 keV. These properties are generally

  4. Combined use of hard X-ray phase contrast imaging and X-ray fluorescence microscopy for sub-cellular metal quantification.

    PubMed

    Kosior, Ewelina; Bohic, Sylvain; Suhonen, Heikki; Ortega, Richard; Devès, Guillaume; Carmona, Asuncion; Marchi, Florence; Guillet, Jean Francois; Cloetens, Peter

    2012-02-01

    Hard X-ray fluorescence microscopy and magnified phase contrast imaging are combined to obtain quantitative maps of the projected metal concentration in whole cells. The experiments were performed on freeze dried cells at the nano-imaging station ID22NI of the European Synchrotron Radiation Facility (ESRF). X-ray fluorescence analysis gives the areal mass of most major, minor and trace elements; it is validated using a biological standard of known composition. Quantitative phase contrast imaging provides maps of the projected mass and is validated using calibration samples and through comparison with Atomic Force Microscopy and Scanning Transmission Ion Microscopy. Up to now, absolute quantification at the sub-cellular level was impossible using X-ray fluorescence microscopy but can be reached with the use of the proposed approach. PMID:22182730

  5. Magnetic structure of a flaring region producing impulsive microwave and hard X-ray bursts

    NASA Technical Reports Server (NTRS)

    Kundu, M. R.; Schmahl, E. J.; Velusamy, T.

    1982-01-01

    Using VLA observations of the 1B/M1 flare of June 25, 1980, 6-cm 'snapshot' maps are synthesized. The spatial and temporal resolutions during the 9 minutes of the impulsive phase were, respectively, 1 arcsec x 2 arcsec and 10 s. Some displacement is noted between the locations of the burst source and the preflare loop structures seen in the preflare map. The burst peak occurred on the neutral line of the preflare polarization map, between the two oppositely polarized microwave 'loop' structures approximately 40 arcsec long. Concurrent hard X-ray observations were made of the burst, although these had no spatial resolution. The 6-cm maps show the locations of a number of the X-ray burst spikes. The 6-cm burst was fully resolved into at least eight components, many of which were bipolar.

  6. Hard X-ray Microscopy with sub 30 nm Spatial Resolution

    NASA Astrophysics Data System (ADS)

    Tang, Mau-Tsu; Song, Yen-Fang; Yin, Gung-Chian; Chen, Fu-Rong; Chen, Jian-Hua; Chen, Yi-Ming; Liang, Keng S.; Duewer, F.; Yun, Wenbing

    2007-01-01

    A transmission X-ray microscope (TXM) has been installed at the BL01B beamline at National Synchrotron Radiation Research Center in Taiwan. This state-of-the-art TXM operational in a range 8-11 keV provides 2D images and 3D tomography with spatial resolution 60 nm, and with the Zernike-phase contrast mode for imaging light materials such as biological specimens. A spatial resolution of the TXM better than 30 nm, apparently the best result in hard X-ray microscopy, has been achieved by employing the third diffraction order of the objective zone plate. The TXM has been applied in diverse research fields, including analysis of failure mechanisms in microelectronic devices, tomographic structures of naturally grown photonic specimens, and the internal structure of fault zone gouges from an earthquake core. Here we discuss the scope and prospects of the project, and the progress of the TXM in NSRRC.

  7. Hard X-ray Microscopy with sub 30 nm Spatial Resolution

    SciTech Connect

    Tang, M.-T.; Song, Y.-F.; Yin, G.-C.; Chen, J.-H.; Chen, Y.-M.; Liang, Keng S.; Chen, F.-R.; Duewer, F.; Yun Wenbing

    2007-01-19

    A transmission X-ray microscope (TXM) has been installed at the BL01B beamline at National Synchrotron Radiation Research Center in Taiwan. This state-of-the-art TXM operational in a range 8-11 keV provides 2D images and 3D tomography with spatial resolution 60 nm, and with the Zernike-phase contrast mode for imaging light materials such as biological specimens. A spatial resolution of the TXM better than 30 nm, apparently the best result in hard X-ray microscopy, has been achieved by employing the third diffraction order of the objective zone plate. The TXM has been applied in diverse research fields, including analysis of failure mechanisms in microelectronic devices, tomographic structures of naturally grown photonic specimens, and the internal structure of fault zone gouges from an earthquake core. Here we discuss the scope and prospects of the project, and the progress of the TXM in NSRRC.

  8. On the nature of the sources of hard pulse X-ray radiation

    NASA Technical Reports Server (NTRS)

    Shklovskiy, I. S.

    1978-01-01

    Besides the identified sources of cosmic pulse X-ray radiation with globular clusters NGC 6624, NGC 1851 and MXB 1730-335 several new identifications were made. The source in Norma was probably identified with globular cluster NGC 5927, the source in Aquila with globular cluster NGC 6838 (M71), and the source in Puppis with globular cluster NGC 2298. Gamma pulses discovered by the Vela satellites and X-ray pulses thoroughly measured by the SAS-3, Ariel-5, and ANS satellites are thought to be the same phenomenon. The sources of such a radiation must be some kind of peculiarity at the central part of globular clusters; it is most probably a massive black hole. The sources of hard pulse radiation which cannot be identified with globular clusters are considered to be a new kind of galactic object, invisible globular clusters, which are naked nuclei of globular clusters.

  9. SMM hard X-ray observations of the soft gamma-ray repeater 1806-20

    NASA Technical Reports Server (NTRS)

    Kouveliotou, C.; Norris, J. P.; Cline, T. L.; Dennis, B. R.; Desai, U. D.; Orwig, L. E.

    1987-01-01

    Six bursts from the soft gamma-ray repeater (SGR) 1806-20 have been recorded with the SMM Hard X-ray Burst Spectrometer during a highly active phase in 1983. Rise and decay times of less than 5 ns have been detected. Time profiles of these events indicate low-level emission prior to and after the main peaks. The results suggest that SGRs are distinguished from classical gamma-ray bursts by repetition, softer nonvarying spectra, short durations, simple temporal profiles, and a tendency for source locations to correlate with Population I objects. SGR characteristics differ from those of type I X-ray bursts, but they appear to have similarities with the type II bursts from the Rapid Burster.

  10. A high sensitivity determination of the hard X-ray spectrum of Sco X-1

    NASA Technical Reports Server (NTRS)

    Rothschild, R. E.; Gruber, D. E.; Knight, F. K.; Nolan, P. L.; Soong, Y.; Levine, A. M.; Primini, F. A.; Lewin, W. H. G.; Wheaton, W. A.

    1980-01-01

    The results of hard X-ray observations of Sco X-1 by HEAO 1 and OSO 7 are reported. The X-ray spectrum between 20 and 70 keV was found consistent with thermal bremsstrahlung from a hot plasma at a temperature of 5.15 plus or minus 0.05 keV. Observations with the instruments of HEAO 1 on Sept. 6-7, 1978, and with those of OSO 7 during 1972, have not confirmed reports that the bremsstrahlung spectrum is accompanied by an extra component at energies greater than 40 keV - the reported observations yield a two-standard deviation upper limit to the flux in this region of 6.4 x 10 to the -6th photons/sq cm/s/keV.

  11. Temporal behaviour of the thermal model of hard X-ray bursts

    NASA Technical Reports Server (NTRS)

    Mackinnon, A. L.

    1985-01-01

    A simple, analytic model is presented of a hot, thermal hard X-ray source, continuously heated, bounded by ion-acoustic conduction fronts, and expanding in a loop. The model is used to investigate the assumption that the 'rise time' of the X-ray emission is approximately given by the loop length divided by the ion-sound speed appropriate to the peak temperature. It is found that a freely-expanding source does not behave in this way; instead, the rise time is symptomatic of the timescale for primary energy release. If the energy release rate does not fall significantly before the source fills the loop, however, then this assumption may be approximately satisfied, if a condition on the temporal behavior of the energy release is satisfied. Finally, some remarks on the relative timing of temperature and emission measure peaks are made, and possible further applications mentioned of the results presented herein.

  12. The high-energy detector of the New Hard X-ray Mission (NHXM): design concept

    NASA Astrophysics Data System (ADS)

    Bellazzini, R.; Brez, A.; Minuti, M.; Pinchera, M.; Spandre, G.; Argan, A.; Catalano, O.; Costa, E.; Fiorini, C.; Malaguti, G.; Pareschi, G.; Tagliaferri, G.; Uslenghi, M.

    2010-07-01

    The New Hard X-ray Mission (NHXM) is conceived to extend the grazing-angle reflection imaging capability up to 80 keV energy. The payload of the mission consists of four telescopes: three of the them having at their focal plane an identical spectral-imaging camera operating between 0.2 and 80 keV, while the fourth one is equipped with a X-ray imaging polarimeter. The three cameras consist of two detection layers: a Low Energy Detector (LED) and a High Energy Detector (HED) surrounded by an Anti Coincidence (AC) system. Here we present the preliminary design and the solutions that we are currently studying to meet the requirements for the high energy detectors. These detectors will be based on Cadmium Telluride (CdTe) pixel sensors coupled to pixel read-out electronics using custom CMOS ASICs.

  13. Background information and technological tests of hard X-ray detectors .

    NASA Astrophysics Data System (ADS)

    Natalucci, L.; Caroli, E.; Quadrini, E.; Del Sordo, S.; Ubertini, P.

    Hard X-ray detectors for astronomical observations are currently being designed with advanced background rejection capabilities, based on high level of pixelisation and on fast signal processing. The development of such devices, based on room temperature semiconductor such as CdTe or CdZnTe comes through extensive testing programs normally based on ground campaigns, using radioactive sources, X-ray tubes and particle beam accelerators. These methods show their limits, however, especially for the measurements of the response to the different types of hadrons. Firtsly, we briefly review the knowledge of the primary sources of background and of the different radiation environments both for space and balloon altitudes, for which typical fluxes/rates are given. Then, we discuss how flying prototypes on high altitude balloons can greatly help to test the detector performance in an environment almost as severe as the conditions found in orbit, with detectors responding at very similar rates.

  14. All dielectric hard x-ray mirror by atomic layer deposition

    SciTech Connect

    Szeghalmi, Adriana; Senz, Stephan; Goesele, Ulrich; Knez, Mato; Bretschneider, Mario

    2009-03-30

    Mirrors consisting of Al{sub 2}O{sub 3} and Ta{sub 2}O{sub 5} ({approx}2 nm film thickness) nanolaminates for hard x-ray wavelengths were produced by atomic layer deposition and characterized. Atomic force microscopy and transmission electron microscopy (TEM) proved extremely smooth surfaces of the mirrors, which are critical for highest reflectance. TEM images showed sharp interfaces between the oxides. The experimental x-ray reflectivity data were theoretically modeled and indicated minimal random thickness variations in the individual layers. Additionally, a depth graded sample with a total thickness of {approx}4 {mu}m for focusing applications in transmission (Laue) geometry and capillaries was coated.

  15. A single-shot transmissive spectrometer for hard x-ray free electron lasers

    SciTech Connect

    Zhu Diling; Cammarata, Marco; Feldkamp, Jan M.; Fritz, David M.; Hastings, Jerome B.; Lee, Sooheyong; Lemke, Henrik T.; Robert, Aymeric; Turner, James L.; Feng Yiping

    2012-07-16

    We report hard x-ray single-shot spectral measurements of the Linac Coherent Light Source. The spectrometer is based on a 10 {mu}m thick cylindrically bent Si single crystal operating in the symmetric Bragg geometry to provide dispersion and high transmission simultaneously. It covers a spectral range >1% using the Si(111) reflection. Using the Si(333) reflection, it reaches a resolving power of better than 42 000 and transmits >83% of the incident flux at 8.3 keV. The high resolution enabled the observation of individual spectral spikes characteristic of a self-amplified spontaneous emission x-ray free electron laser source. Potential applications of the device are discussed.

  16. DIFFUSE HARD X-RAY EMISSION IN STARBURST GALAXIES AS SYNCHROTRON FROM VERY HIGH ENERGY ELECTRONS

    SciTech Connect

    Lacki, Brian C.; Thompson, Todd A.

    2013-01-01

    The origin of the diffuse hard X-ray (2-10 keV) emission from starburst galaxies is a long-standing problem. We suggest that synchrotron emission of 10-100 TeV electrons and positrons (e {sup {+-}}) can contribute to this emission, because starbursts have strong magnetic fields. We consider three sources of e {sup {+-}} at these energies: (1) primary electrons directly accelerated by supernova remnants, (2) pionic secondary e {sup {+-}} created by inelastic collisions between cosmic ray (CR) protons and gas nuclei in the dense interstellar medium of starbursts, and (3) pair e {sup {+-}} produced between the interactions between 10 and 100 TeV {gamma}-rays and the intense far-infrared (FIR) radiation fields of starbursts. We create one-zone steady-state models of the CR population in the Galactic center (R {<=} 112 pc), NGC 253, M82, and Arp 220's nuclei, assuming a power-law injection spectrum for electrons and protons. We consider different injection spectral slopes, magnetic field strengths, CR acceleration efficiencies, and diffusive escape times, and include advective escape, radiative cooling processes, and secondary and pair e {sup {+-}}. We compare these models to extant radio and GeV and TeV {gamma}-ray data for these starbursts, and calculate the diffuse synchrotron X-ray and inverse Compton (IC) luminosities of these starbursts in the models which satisfy multiwavelength constraints. If the primary electron spectrum extends to {approx}PeV energies and has a proton/electron injection ratio similar to the Galactic value, we find that synchrotron emission contributes 2%-20% of their unresolved, diffuse hard X-ray emission. However, there is great uncertainty in this conclusion because of the limited information on the CR electron spectrum at these high energies. IC emission is likewise a minority of the unresolved X-ray emission in these starbursts, from 0.1% in the Galactic center to 10% in Arp 220's nuclei, with the main uncertainty being the starbursts

  17. Diffuse Hard X-Ray Emission in Starburst Galaxies as Synchrotron from Very High Energy Electrons

    NASA Astrophysics Data System (ADS)

    Lacki, Brian C.; Thompson, Todd A.

    2013-01-01

    The origin of the diffuse hard X-ray (2-10 keV) emission from starburst galaxies is a long-standing problem. We suggest that synchrotron emission of 10-100 TeV electrons and positrons (e ±) can contribute to this emission, because starbursts have strong magnetic fields. We consider three sources of e ± at these energies: (1) primary electrons directly accelerated by supernova remnants, (2) pionic secondary e ± created by inelastic collisions between cosmic ray (CR) protons and gas nuclei in the dense interstellar medium of starbursts, and (3) pair e ± produced between the interactions between 10 and 100 TeV γ-rays and the intense far-infrared (FIR) radiation fields of starbursts. We create one-zone steady-state models of the CR population in the Galactic center (R <= 112 pc), NGC 253, M82, and Arp 220's nuclei, assuming a power-law injection spectrum for electrons and protons. We consider different injection spectral slopes, magnetic field strengths, CR acceleration efficiencies, and diffusive escape times, and include advective escape, radiative cooling processes, and secondary and pair e ±. We compare these models to extant radio and GeV and TeV γ-ray data for these starbursts, and calculate the diffuse synchrotron X-ray and inverse Compton (IC) luminosities of these starbursts in the models which satisfy multiwavelength constraints. If the primary electron spectrum extends to ~PeV energies and has a proton/electron injection ratio similar to the Galactic value, we find that synchrotron emission contributes 2%-20% of their unresolved, diffuse hard X-ray emission. However, there is great uncertainty in this conclusion because of the limited information on the CR electron spectrum at these high energies. IC emission is likewise a minority of the unresolved X-ray emission in these starbursts, from 0.1% in the Galactic center to 10% in Arp 220's nuclei, with the main uncertainty being the starbursts' magnetic field. We also model generic starbursts, including

  18. Hard x-ray photoelectron spectroscopy using an environmental cell with silicon nitride membrane windows

    SciTech Connect

    Tsunemi, Eika; Watanabe, Yoshio; Oji, Hiroshi; Cui, Yi-Tao; Son, Jin-Young

    2015-06-21

    We applied hard x-ray photoelectron spectroscopy (HAXPES) to a sample under ambient pressure conditions using an environmental cell with an approximately 24 nm-thick SiN{sub x} membrane window. As a model chemical substance, europium (II) iodide (EuI{sub 2}) sealed in the cell with argon gas was investigated with HAXPES to identify the chemical species present inside the cell. The optical and morphological properties of the sample within the cell were measured with optical and fluorescent microscopy, scanning electron microscopy, cathodoluminescence, and energy dispersive x-ray spectrometry. We confirmed the effectiveness of the gas barrier properties of the cell with the SiN{sub x} window and demonstrated its applicability to various other optical and electron measurements as well as HAXPES.

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

    NASA Astrophysics Data System (ADS)

    Hirotomo, Toshiki; Takano, Hidekazu; Sumida, Kazuhiro; Koyama, Takahisa; Konishi, Shigeki; Ichimaru, Satoshi; Ohchi, Tadayuki; Takenaka, Hisataka; Tsusaka, Yoshiyuki; Kagoshima, Yasushi

    2016-01-01

    Multilayer zone plate (MZP) technology for hard X-ray focusing was upgraded and its focusing performance was evaluated using 20-keV X-rays at the synchrotron beamline (BL24XU) of SPring-8. The MZP consists of MoSi2 and Si layers alternately deposited on a glass fiber by magnetron sputtering so that all zone boundaries satisfy the Fresnel zone configuration. The focused beam was evaluated using knife-edge scanning in which the measured intensity distribution is identical to the line spread function (LSF) in the focal plane. The focused beamsize of about 30 nm was estimated by oscillation peaks observed in the measured LSF according to Rayleigh's criterion.

  20. Claudio Pellegrini and the World’s First Hard X-ray Free-Electron Laser

    SciTech Connect

    Pellegrini, Claudio

    2015-10-20

    President Obama welcomed SLAC's Claudio Pellegrini inside the Oval Office on Tuesday morning as a recipient of the Enrico Fermi Award, one of the highest honors the U.S. government can give to a scientist. Pellegrini, a visiting scientist and consulting professor at SLAC and distinguished professor emeritus at the University of California, Los Angeles, received the award for research that aided in the development of X-ray free-electron lasers (XFELs) including SLAC's Linac Coherent Light Source (LCLS), a DOE Office of Science User Facility that started up in 2009. Here, Pellegrini describes his efforts that contributed to the realization of SLAC’s Linac Coherent Light Source, the world’s first hard X-ray free-electron laser.

  1. Iron Line and Diffuse Hard X-Ray Emission from the Starburst Galaxy M82

    NASA Astrophysics Data System (ADS)

    Strickland, David K.; Heckman, Timothy M.

    2007-03-01

    We examine the properties of the diffuse hard X-ray emission in the classic starburst galaxy M82. We use new Chandra ACIS-S observations in combination with reprocessed archival Chandra ACIS-I and XMM-Newton observations. We find that E~6.7 keV Fe Heα emission is present in the central |r|<200 pc, |z|<100 pc of M82 in all data sets, in addition to a possibly nonthermal X-ray continuum and marginally significant E=6.4 keV Fe Kα line emission. No statistically significant Fe emission is found in the summed X-ray spectra of the pointlike X-ray sources or the ULXs in the two epochs of Chandra observation. The total nuclear region iron line fluxes in the 2004 April 21 XMM-Newton observation are consistent with those of the Chandra-derived diffuse component, but in the 2001 May 6 XMM-Newton observation they are significantly higher and also both E=6.4 and 6.9 keV iron lines are detected. We attribute the excess iron line emission to the ULX in its high state. In general, the iron K-shell luminosity of M82 is dominated by the diffuse component. The total X-ray luminosity of the diffuse hard X-ray emission is LX,2-8keV~4.4×1039 ergs s-1 in the E=2-8 keV energy band, and the 6.7 keV iron line luminosity is LX,6.7keV~(1.1-1.7)×1038 ergs s-1. The 6.7 keV iron line luminosity is consistent with that expected from the previously unobserved metal-enriched merged SN ejecta that is thought to drive the larger scale galactic superwind. The iron line luminosity implies a thermal pressure within the starburst region of P/k~2×107 K cm-3, consistent with independent observational estimates of the starburst region pressure.

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

    NASA Astrophysics Data System (ADS)

    Hailey, Charles J.; Mori, Kaya; Perez, Kerstin; Canipe, Alicia M.; Hong, Jaesub; Tomsick, John A.; Boggs, Steven E.; Christensen, Finn E.; Craig, William W.; Fornasini, Francesca; Grindlay, Jonathan E.; Harrison, Fiona A.; Nynka, Melania; Rahoui, Farid; Stern, Daniel; Zhang, Shuo; Zhang, William W.

    2016-08-01

    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 < {M}{{WD}}> ≈ 0.5{M}ȯ . Here we use broadband NuSTAR observations of two IPs: TV Columbae, which has a fairly typical but widely varying reported mass of {M}{{WD}}≈ 0.5–1.0{M}ȯ , and IGR J17303–0601, with a heavy reported mass of {M}{{WD}}≈ 1.0–1.2{M}ȯ . We investigate how varying spectral models and observed energy ranges influences estimated white dwarf mass. Observations of the inner 10 pc can be accounted for by IPs with < {M}{{WD}}> ≈ 0.9{M}ȯ , 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-band fitting. To explain the (unresolved) central hard X-ray emission (CHXE) by IPs requires an X-ray (2–8 keV) luminosity function (XLF) extending down to at least 5 × 1031 erg s‑1. The CHXE XLF, if extended to the surrounding ˜50 pc observed by Chandra and XMM-Newton, requires that at least ˜20%–40% of the ˜9000 point sources are IPs. If the XLF extends just a factor of a few lower in luminosity, then the vast majority of these sources are IPs. This is in contrast to recent observations of the Galactic ridge, where the bulk of the 2–8 keV emission is ascribed to non-magnetic CVs.

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

    NASA Astrophysics Data System (ADS)

    Hailey, Charles J.; Mori, Kaya; Perez, Kerstin; Canipe, Alicia M.; Hong, Jaesub; Tomsick, John A.; Boggs, Steven E.; Christensen, Finn E.; Craig, William W.; Fornasini, Francesca; Grindlay, Jonathan E.; Harrison, Fiona A.; Nynka, Melania; Rahoui, Farid; Stern, Daniel; Zhang, Shuo; Zhang, William W.

    2016-08-01

    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 < {M}{{WD}}> ≈ 0.5{M}ȯ . Here we use broadband NuSTAR observations of two IPs: TV Columbae, which has a fairly typical but widely varying reported mass of {M}{{WD}}≈ 0.5–1.0{M}ȯ , and IGR J17303–0601, with a heavy reported mass of {M}{{WD}}≈ 1.0–1.2{M}ȯ . We investigate how varying spectral models and observed energy ranges influences estimated white dwarf mass. Observations of the inner 10 pc can be accounted for by IPs with < {M}{{WD}}> ≈ 0.9{M}ȯ , 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-band fitting. To explain the (unresolved) central hard X-ray emission (CHXE) by IPs requires an X-ray (2–8 keV) luminosity function (XLF) extending down to at least 5 × 1031 erg s‑1. The CHXE XLF, if extended to the surrounding ∼50 pc observed by Chandra and XMM-Newton, requires that at least ∼20%–40% of the ∼9000 point sources are IPs. If the XLF extends just a factor of a few lower in luminosity, then the vast majority of these sources are IPs. This is in contrast to recent observations of the Galactic ridge, where the bulk of the 2–8 keV emission is ascribed to non-magnetic CVs.

  4. Host Galaxy Properties of the Swift BAT Ultra Hard X-Ray Selected AGN

    NASA Technical Reports Server (NTRS)

    Koss, Michael; Mushotzky, Richard; Veilleux, Sylvain; Winter, Lisa M.; Baumgartner, Wayne; Tueller, Jack; Gehrels, Neil; Valencic, Lynne

    2011-01-01

    We have assembled the largest sample of ultra hard X-ray selected (14-195 keV) AGN with host galaxy optical data to date, with 185 nearby (z<0.05), moderate luminosity AGN from the Swift Burst Alert Telescope (BAT) sample. The BAT AGN host galaxies have intermediate optical colors (u -- r and g -- r) that are bluer than a comparison sample of inactive galaxies and optically selected AGN from the Sloan Digital Sky Survey (SDSS) which are chosen to have the same stellar mass. Based on morphological classifications from the RC3 and the Galaxy Zoo, the bluer colors of BAT AGN are mainly due to a higher fraction of mergers and massive spirals than in the comparison samples. BAT AGN in massive galaxies (log Stellar Mass >10.5) have a 5 to 10 times higher rate of spiral morphologies than in SDSS AGN or inactive galaxies. We also see enhanced far-IR emission in BAT AGN suggestive of higher levels of star formation compared to the comparison samples. BAT AGN are preferentially found in the most massive host galaxies with high concentration indexes indicative of large bulge-to-disk ratios and large supermassive black holes. The narrow-line (NL) BAT AGN have similar intrinsic luminosities as the SDSS NL Seyferts based on measurements of [O III] Lambda 5007. There is also a correlation between the stellar mass and X-ray emission. The BAT AGN in mergers have bluer colors and greater ultra hard X-ray emission compared to the BAT sample as whole. In agreement with the Unified Model of AGN, and the relatively unbiased nature of the BAT sources, the host galaxy colors and morphologies are independent of measures of obscuration such as X-ray column density or Seyfert type. The high fraction of massive spiral galaxies and galaxy mergers in BAT AGN suggest that host galaxy morphology is related to the activation and fueling of local AGN.

  5. HOST GALAXY PROPERTIES OF THE SWIFT BAT ULTRA HARD X-RAY SELECTED ACTIVE GALACTIC NUCLEUS

    SciTech Connect

    Koss, Michael; Mushotzky, Richard; Veilleux, Sylvain; Winter, Lisa M.; Baumgartner, Wayne; Tueller, Jack; Gehrels, Neil; Valencic, Lynne

    2011-10-01

    We have assembled the largest sample of ultra hard X-ray selected (14-195 keV) active galactic nucleus (AGN) with host galaxy optical data to date, with 185 nearby (z < 0.05), moderate luminosity AGNs from the Swift BAT sample. The BAT AGN host galaxies have intermediate optical colors (u - r and g - r) that are bluer than a comparison sample of inactive galaxies and optically selected AGNs from the Sloan Digital Sky Survey (SDSS) which are chosen to have the same stellar mass. Based on morphological classifications from the RC3 and the Galaxy Zoo, the bluer colors of BAT AGNs are mainly due to a higher fraction of mergers and massive spirals than in the comparison samples. BAT AGNs in massive galaxies (log M{sub *} >10.5) have a 5-10 times higher rate of spiral morphologies than in SDSS AGNs or inactive galaxies. We also see enhanced far-infrared emission in BAT AGN suggestive of higher levels of star formation compared to the comparison samples. BAT AGNs are preferentially found in the most massive host galaxies with high concentration indexes indicative of large bulge-to-disk ratios and large supermassive black holes. The narrow-line (NL) BAT AGNs have similar intrinsic luminosities as the SDSS NL Seyferts based on measurements of [O III] {lambda}5007. There is also a correlation between the stellar mass and X-ray emission. The BAT AGNs in mergers have bluer colors and greater ultra hard X-ray emission compared to the BAT sample as a whole. In agreement with the unified model of AGNs, and the relatively unbiased nature of the BAT sources, the host galaxy colors and morphologies are independent of measures of obscuration such as X-ray column density or Seyfert type. The high fraction of massive spiral galaxies and galaxy mergers in BAT AGNs suggest that host galaxy morphology is related to the activation and fueling of local AGN.

  6. Statistical study of the correlation of hard X-ray and type III radio bursts in solar flares

    NASA Technical Reports Server (NTRS)

    Hamilton, Russell J.; Petrosian, Vahe; Benz, A. O.

    1990-01-01

    A large number of hard X-ray events which occurred during the maximum of solar cycle 21 have been analyzed in order to study their correlation with type III bursts. It is found that the distribution of occurrences of hard X-ray bursts correlated with type III radio bursts is significantly different from the distribution of all hard X-ray bursts. This result is consistent with the assumption that the hard X-ray and type III intensities are somewhat correlated. A bivariate distribution function of the burst intensities is fitted to the data and is used to determine that the typical ratio of X-ray intensity to type II intensity is about 10 and that the ratio of the number of X-ray producing-electrons to type III-producing electrons is about 1000. Three models which have been proposed to explain the relation between the accelerated hard X-ray and type III-producing electrons are examined in the context of these observations.

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

    SciTech Connect

    Liu, Chian; Ice, Gene E; Liu, Wenjun; Assoufid, Lahsen; Qian, J; Shi, B.; Khachatryan, Ruben; Wieczorek, M.; Zschack, P.; Tischler, Jonathan Zachary

    2012-01-01

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

  8. Hiresmon: A Fast High Resolution Beam Position Monitor for Medium Hard and Hard X-Rays

    SciTech Connect

    Menk, Ralf Hendrik; Giuressi, Dario; Arfelli, Fulvia; Rigon, Luigi

    2007-01-19

    The high-resolution x-ray beam position monitor (XBPM) is based on the principle of a segmented longitudinal ionization chamber with integrated readout and USB2 link. In contrast to traditional transversal ionization chambers here the incident x-rays are parallel to the collecting field which allows absolute intensity measurements with a precision better than 0.3 %. Simultaneously the beam position in vertical and horizontal direction can be measured with a frame rate of one kHz. The precision of position encoding depends only on the SNR of the synchrotron radiation and is in the order of micro meters at one kHz frame rate and 108 photon /sec at 9 KeV.

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

    PubMed

    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. PMID:25882736

  10. Suzaku observations of the hard X-ray spectrum of Vela Jr. (SNR RX J0852.0-4622)

    NASA Astrophysics Data System (ADS)

    Takeda, Sawako; Bamba, Aya; Terada, Yukikatsu; Tashiro, Makoto S.; Katsuda, Satoru; Yamazaki, Ryo; Ohira, Yutaka; Iwakiri, Wataru

    2016-06-01

    We report the results of Suzaku observations of the young supernova remnant, Vela Jr. (RX J0852.0-4622), which is known to emit synchrotron X-rays, as well as TeV gamma-rays. Utilizing 39 Suzaku mapping observation data from Vela Jr., a significant hard X-ray emission is detected with the hard X-ray detector (HXD) from the northwest TeV-emitting region. The X-ray spectrum is reproduced well by a single power-law model with a photon index of 3.15^{+1.18}_{-1.14} in the 12-22 keV band. Compiling this hard X-ray spectrum with the soft X-ray spectrum simultaneously observed with the X-ray imaging spectrometer (XIS) onboard Suzaku, we find that the wide-band X-ray spectrum in the 2-22 keV band is reproduced with a single power-law or concave broken power-law model, which are statistically consistent with each other. Whichever of the two models, single or broken power-law, is appropriate, clearly the spectrum has no roll-off structure. Applying this result to the method introduced in Yamazaki et al. (2014, Res. Astron. Astrophys., 14, 165), we find that a one-zone synchrotron model with electron spectrum having a power-law plus exponential cut-off may not be applicable to Vela Jr.

  11. Fabrication, characterization and integration of carbon nanotube cathodes for field emission X-ray source

    NASA Astrophysics Data System (ADS)

    Calderon-Colon, Xiomara

    Carbon nanotube (CNT) field emitters are now being evaluated for a wide range of vacuum electronic applications. Our laboratory pioneer in the development of CNT based field emission X-ray source technology, which has the potential to fundamentally change how X-ray radiation is generated and utilized. Applications of the CNT field emission X-ray source technology in a wide range of applications including biomedical imaging, radiation therapy, and homeland security are being actively pursued. However, problems with the performance of the CNT cathodes for X-ray generation including short lifetime at high current density, instability under high voltage, poor emission uniformity, and cathode-to-cathode inconsistency are still major obstacles for device applications. The goal of this thesis work is the development and optimization of an electrophoretic process to fabricate composite CNT films with controlled nanotube orientation and surface density, and enhanced adhesion. The CNT cathode fabrication process consist in a combination of photolithography and electrophoretic deposition (EPD) method where parameters such as SU-8 photoresist thickness, deposition time, and deposition voltage were varied to fabricate CNT cathodes with the required properties for X-ray generation. Also the development of CNT alcohol-based suspensions in context of the EPD method requirements with excellent long term stability has been accomplished. The CNT cathodes fabricated by EPD have significantly enhanced macroscopic field emission current density and long-term stability under high operating voltages. Also these CNT cathodes compared to others reported previously show significant improved field emission properties with small cathode-to-cathode variation. The integration, characterization, and evaluation of these CNT cathodes into a micro focus field emission X-ray source has been achieved with excellent X-ray source characteristics and performance including X-ray flux and stability at the

  12. Spectral evolution of microwaves and hard X-rays in the 1989 March 18 flare and its interpretation

    NASA Technical Reports Server (NTRS)

    Lee, Jeongwoo W.; Gary, Dale E.

    1994-01-01

    We analyze the time variation of microwave spectra and hard X-ray spectra of 1989 March 18, which are obtained from the Solar Array at the Owens Valley Radio Observatory (OVRO) and the Hard X-Ray Burst Spectrometer (HXRBS) on the Solar Maximum Mission (SMM), respectively. From this observation, it is noted that the hard X-ray spectra gradually soften over 50 - 200 keV on-and-after the maximum phase while the microwaves at 1 - 15 GHz show neither a change in spectral shape nor as rapid a decay as hard X-rays. This leads to decoupling of hard X-rays from the microwaves in the decay phase away from their good correlation seen in the initial rise phase. To interpret this observation, we adopt a view that microwave-emitting particles and hard X-ray particles are physically separated in an inhomogeneous magnetic loop, but linked via interactions with the Whistler waves generated during flares. From this viewpoint, it is argued that the observed decoupling of microwaves from hard X-rays may be due to the different ability of each source region to maintain high energy electrons in response to the Whistler waves passing through the entire loop. To demonstrate this possibility, we solve a Fokker-Planck equation that describes evolution of electrons interacting with the Whistler waves, taking into account the variation of Fokker-Planck coefficients with physical quantities of the background medium. The numerical Fokker-Planck solutions are then used to calculate microwave spectra and hard X-ray spectra for agreement with observations. Our model results are as follows: in a sronger field region, the energy loss by electron escape due to scattering by the waves is greatly enhanced resulting in steep particle distributions that reproduce the observed hard X-ray spectra. In a region with weaker fields and lower density, this loss term is reduced allowing high energy electrons to survive longer so that microwaves can be emitted there in excess of hard X-rays during the decay phase

  13. Development of a prototype nickel optic for the Constellation-X hard x-ray telescope: IV

    NASA Astrophysics Data System (ADS)

    Romaine, S.; Basso, S.; Bruni, R. J.; Burkert, W.; Citterio, O.; Conti, G.; Engelhaupt, D.; Freyberg, M. J.; Ghigo, M.; Gorenstein, P.; Gubarev, M.; Hartner, G.; Mazzoleni, F.; O'Dell, S.; Pareschi, G.; Ramsey, B. D.; Speegle, C.; Spiga, D.

    2006-06-01

    The Constellation-X mission planned for launch in 2015-2020 timeframe, will feature an array of Hard X-ray telescopes (HXT) with a total collecting area greater than 1500 cm2 at 40 keV. Two technologies are being investigated for the optics of these telescopes, one of which is multilayer-coated Electroformed-Nickel-Replicated (ENR) shells. The attraction of the ENR process is that the resulting full-shell optics are inherently stable and offer the prospect of better angular resolution which results in lower background and higher instrument sensitivity. We are building a prototype HXT mirror module using an ENR process to fabricate the individual shells. This prototype consists of 5 shells with diameters ranging from 15 cm to 28 cm with a length of 42.6 cm. The innermost of these will be coated with iridium, while the remainder will be coated with graded d-spaced W/Si multilayers. The assembly structure has been completed and last year we reported on full beam illumination results from the first test shell mounted in this structure. We have now fabricated and coated two (15 cm and 23 cm diameter) 100 micron thick shells which have been aligned and mounted. This paper presents the results of full beam illumination X-ray tests, taken at MPE-Panter. The HEW of the individual shells will be discussed, in addition to results from the full two shell optic test.

  14. INTEGRAL measures the hard X-ray spectrum of the Be/X-ray binary XTE J1859+083

    NASA Astrophysics Data System (ADS)

    Malyshev, D.; Gotz, C. Ferrigno D.

    2015-04-01

    During the INTEGRAL observations performed from 2015 April 17, 19:47 to April 19, 20:01 UTC, the IBIS/ISGRI instrument detected a highly significant signal from a transient source, positionally coincident with the Be/X-ray pulsar XTE J1859+083 (ra, dec) = (284.78 ; 8.25) , which is reported to be in outburst since 2015-02-08 (ATeL #7034).

  15. Development of High Resolution Mirrors and Cd-Zn-Te Detectors for Hard X-ray Astronomy

    NASA Technical Reports Server (NTRS)

    Ramsey, Brian D.; Speegle, Chet O.; Gaskin, Jessica; Sharma, Dharma; Engelhaupt, Darell; Six, N. Frank (Technical Monitor)

    2002-01-01

    We describe the fabrication and implementation of a high-resolution conical, grazing- incidence, hard X-ray (20-70 keV) telescope. When flown aboard stratospheric balloons, these mirrors are used to image cosmic sources such as supernovae, neutron stars, and quasars. The fabrication process involves generating super-polished mandrels, mirror shell electroforming, and mirror testing. The cylindrical mandrels consist of two conical segments; each segment is approximately 305 mm long. These mandrels are first, precision ground to within approx. 1.0 micron straightness along each conical segment and then lapped and polished to less than 0.5 micron straightness. Each mandrel segment is the super-polished to an average surface roughness of approx. 3.25 angstrom rms. By mirror shell replication, this combination of good figure and low surface roughness has enabled us to achieve 15 arcsec, confirmed by X-ray measurements in the Marshall Space Flight Center 102 meter test facility. To image the focused X-rays requires a focal plane detector with appropriate spatial resolution. For 15 arcsec optics of 6 meter focal length, this resolution must be around 200 microns. In addition, the detector must have a high efficiency, relatively high energy resolution, and low background. We are currently developing Cadmium-Zinc-Telluride fine-pixel detectors for this purpose. The detectors under study consist of a 16x16 pixel array with a pixel pitch of 300 microns and are 1 mm and 2 mm thick. At 60 keV, the measured energy resolution is around 2%.

  16. Modeling Flare Hard X-ray Emission from Electrons in Contracting Magnetic Islands

    NASA Astrophysics Data System (ADS)

    Guidoni, Silvina E.; Allred, Joel C.; Alaoui, Meriem; Holman, Gordon D.; DeVore, C. Richard; Karpen, Judith T.

    2016-05-01

    The mechanism that accelerates particles to the energies required to produce the observed impulsive hard X-ray emission in solar flares is not well understood. It is generally accepted that this emission is produced by a non-thermal beam of electrons that collides with the ambient ions as the beam propagates from the top of a flare loop to its footpoints. Most current models that investigate this transport assume an injected beam with an initial energy spectrum inferred from observed hard X-ray spectra, usually a power law with a low-energy cutoff. In our previous work (Guidoni et al. 2016), we proposed an analytical method to estimate particle energy gain in contracting, large-scale, 2.5-dimensional magnetic islands, based on a kinetic model by Drake et al. (2010). We applied this method to sunward-moving islands formed high in the corona during fast reconnection in a simulated eruptive flare. The overarching purpose of the present work is to test this proposed acceleration model by estimating the hard X-ray flux resulting from its predicted accelerated-particle distribution functions. To do so, we have coupled our model to a unified computational framework that simulates the propagation of an injected beam as it deposits energy and momentum along its way (Allred et al. 2015). This framework includes the effects of radiative transfer and return currents, necessary to estimate flare emission that can be compared directly to observations. We will present preliminary results of the coupling between these models.

  17. The Effects of Low- and High-Energy Cutoffs on Solar Flare Microwave and Hard X-Ray Spectra

    NASA Technical Reports Server (NTRS)

    Holman, G. D.; Oegerle, William (Technical Monitor)

    2002-01-01

    Microwave and hard x-ray spectra provide crucial information about energetic electrons and their environment in solar flares. These spectra are becoming better determined with the Owens Valley Solar Array (OVSA) and the recent launch of the Ramaty High Energy Solar Spectroscopic Imager (RHESSI). The proposed Frequency Agile Solar Radiotelescope (FASR) promises even greater advances in radio observations of solar flares. Both microwave and hard x-ray spectra are sensitive to cutoffs in the electron distribution function. The determination of the high-energy cutoff from these spectra establishes the highest electron energies produced by the acceleration mechanism, while determination of the low-energy cutoff is crucial to establishing the total energy in accelerated electrons. This paper will show computations of the effects of both high- and low-energy cutoffs on microwave and hard x-ray spectra. The optically thick portion of a microwave spectrum is enhanced and smoothed by a low-energy cutoff, while a hard x-ray spectrum is flattened below the cutoff energy. A high-energy cutoff steepens the microwave spectrum and increases the wavelength at which the spectrum peaks, while the hard x-ray spectrum begins to steepen at photon energies roughly an order of magnitude below the electron cutoff energy. This work discusses how flare microwave and hard x-ray spectra can be analyzed together to determine these electron cutoff energies. This work is supported in part by the NASA Sun-Earth Connection Program.

  18. The radio/X-ray correlation in Cyg X-3 and the nature of its hard spectral state

    NASA Astrophysics Data System (ADS)

    Zdziarski, Andrzej A.; Segreto, Alberto; Pooley, Guy G.

    2016-02-01

    We study the radio/X-ray correlation in Cyg X-3. It has been known that the soft and hard X-ray fluxes in the hard spectral state are correlated positively and negatively, respectively, with the radio flux. We show that this implies that the observed ˜1-100 keV flux (which is a fair approximation to the bolometric flux) is completely uncorrelated with the radio flux. We can recover a positive correlation (seen in other sources and expected theoretically) if the soft X-rays are strongly absorbed by a local medium. Then, however, the intrinsic X-ray spectrum of Cyg X-3 in its hard state becomes relatively soft, similar to that of an intermediate spectral state of black hole binaries, but not to their true hard state. We also find the radio spectra in the hard state of Cyg X-3 are hard on average, and the flux distributions of the radio emission and soft X-rays can be described by sums of two lognormal functions. We compare Cyg X-3 with other X-ray binaries using colour-colour, colour-Eddington ratio and Eddington ratio-radio flux diagrams. We find Cyg X-3 to be spectrally most similar to GRS 1915+105, except that Cyg X-3 is substantially more radio loud, which appears to be due to its jet emission enhanced by interaction with the powerful stellar wind from the Wolf-Rayet donor.

  19. X-ray spectromicroscopy investigation of soft and hard breakdown in RRAM devices

    NASA Astrophysics Data System (ADS)

    Carta, D.; Guttmann, P.; Regoutz, A.; Khiat, A.; Serb, A.; Gupta, I.; Mehonic, A.; Buckwell, M.; Hudziak, S.; Kenyon, A. J.; Prodromakis, T.

    2016-08-01

    Resistive random access memory (RRAM) is considered an attractive candidate for next generation memory devices due to its competitive scalability, low-power operation and high switching speed. The technology however, still faces several challenges that overall prohibit its industrial translation, such as low yields, large switching variability and ultimately hard breakdown due to long-term operation or high-voltage biasing. The latter issue is of particular interest, because it ultimately leads to device failure. In this work, we have investigated the physicochemical changes that occur within RRAM devices as a consequence of soft and hard breakdown by combining full-field transmission x-ray microscopy with soft x-ray spectroscopic analysis performed on lamella samples. The high lateral resolution of this technique (down to 25 nm) allows the investigation of localized nanometric areas underneath permanent damage of the metal top electrode. Results show that devices after hard breakdown present discontinuity in the active layer, Pt inclusions and the formation of crystalline phases such as rutile, which indicates that the temperature increased locally up to 1000 K.

  20. X-ray spectromicroscopy investigation of soft and hard breakdown in RRAM devices.

    PubMed

    Carta, D; Guttmann, P; Regoutz, A; Khiat, A; Serb, A; Gupta, I; Mehonic, A; Buckwell, M; Hudziak, S; Kenyon, A J; Prodromakis, T

    2016-08-26

    Resistive random access memory (RRAM) is considered an attractive candidate for next generation memory devices due to its competitive scalability, low-power operation and high switching speed. The technology however, still faces several challenges that overall prohibit its industrial translation, such as low yields, large switching variability and ultimately hard breakdown due to long-term operation or high-voltage biasing. The latter issue is of particular interest, because it ultimately leads to device failure. In this work, we have investigated the physicochemical changes that occur within RRAM devices as a consequence of soft and hard breakdown by combining full-field transmission x-ray microscopy with soft x-ray spectroscopic analysis performed on lamella samples. The high lateral resolution of this technique (down to 25 nm) allows the investigation of localized nanometric areas underneath permanent damage of the metal top electrode. Results show that devices after hard breakdown present discontinuity in the active layer, Pt inclusions and the formation of crystalline phases such as rutile, which indicates that the temperature increased locally up to 1000 K. PMID:27420908

  1. GRAPE: A Balloon-Borne Hard X-ray Polarimeter for Solar Flares

    NASA Astrophysics Data System (ADS)

    Bloser, Peter F.; McConnell, M. L.; Legere, J. S.; Macri, J. R.; Ryan, J. M.; Narita, T.

    2006-06-01

    We present the current status of the gamma-ray polarimetry experiment (GRAPE) project to measure linear polarization in solar flares in the hard X-ray range (50-300 keV). Polarimetry measurements offer a new way to measure the extent to which energetic electrons in flares are beamed, which has important implications for particle acceleration models. Each GRAPE detector consists of an array of plastic scintillators and high-Z calorimeter crystals read out by a single multi-anode photomultiplier tube (MAPMT). X-ray photons Compton scatter in the plastic elements and are subsequently absorbed in the calorimeter elements, and the azimuthal scattering angle and total energy are recorded. The degree of asymmetry in the distribution of scatter angles reveals the degree of linear polarization in the incident X-rays. We present our latest laboratory test results and describe plans for a balloon flight of a prototype and for a full balloon-borne science payload. Monte Carlo simulations indicate that an array of 25 GRAPE detectors carried on a scientific balloon would be sensitive to polarization levels of 5% or less for a M5 flare in a 5 minute exposure.

  2. Examining the hard X-ray emission of the redback PSR J2129-0429

    NASA Astrophysics Data System (ADS)

    Noori, Hind Al; Roberts, Mallory; McLaughlin, Maura; Hessels, Jason; Breton, Rene; 17077031498

    2016-06-01

    We present new NuStar data of the redback millisecond pulsar (MSP) system PSR J2129-0429. Redback systems are important when it comes to understanding the evolution of MSPs, in terms of pulsar recycling, as they have been observed to transition between a state of accretion, where emission is in the optical and X-ray regimes, and a state of eclipsed radio pulsation. This system is particularly interesting due to some peculiarities: it has a more massive companion as well as a stronger magnetic field than other redbacks, indicating that the system is in a fairly early stage of recycling. It’s X-ray lightcurve (as obtained from XMM-Newton data) has a very hard power-law component and exhibits an efficiency of a few percent in X-ray. With the NuStar data, the spectrum can be seen to extend to ~30 keV. Additionally, it shows strong orbital variation, about 5 times greater than is typical for other systems, and is also very clearly double peaked. Hints of similar peaks have been observed in the lightcurves of other redback systems; hence, this system can help in understanding the intrabinary shock of eclipsing MSPs.

  3. Evidence for Intermediate Polars as the origin of the Galactic Center hard X-ray emission

    NASA Astrophysics Data System (ADS)

    Hailey, Charles James; NuSTAR Galactic Plane Survey Working Group

    2016-01-01

    Recently, NuSTAR has discovered an unresolved hard (20-40 keV) X-ray emission within the central 10 pc of the Galaxy, possibly indicating a large population of intermediate polars (IPs). Chandra and XMM-Newton measurements of both point sources and diffuse emission in the surrounding ~50 pc imply a population of magnetic CVs with white dwarf mass ~ 0.5 M⊙. We present NuSTAR broad-band (3-79 keV) spectroscopy of two nearby IPs (TV Columbae and IGR J17303-0601) as well as our investigation of various spectral models and previous X-ray observations. We argue that the observations of both the inner 10 pc and the surrounding 50 pc can be accounted for by IPs with mean white dwarf mass ~ 0.9 M⊙. We find that the lower mass derived by Chandra and XMM-Newton is an artifact of narrow energy band fitting, and the spectral features associated with these measurements naturally arise in a heavier IP population. We also discuss implications for the X-ray emission and source population in the Galactic ridge and bulge.

  4. Accelerated electrons and hard X-ray emission from X-pinches

    SciTech Connect

    Shelkovenko, T. A.; Pikuz, S. A.; Mingaleev, A. R.; Agafonov, A. V.; Romanova, V. M.; Ter-Oganes'yan, A. E.; Tkachenko, S. I.; Blesener, I. C.; Mitchell, M. D.; Chandler, K. M.; Kusse, B. R.; Hammer, D. A.

    2008-09-15

    The generation of accelerated electrons in the X-pinch minidiode is studied experimentally. It is well known that the explosion of an X-pinch consisting of two or more wires is accompanied by the formation of a minidiode, in which electrons are accelerated. The subsequent slowing down of electrons in the products of wire explosion causes the generation of hard X-ray (HXR) emission with photon energies higher than 10 keV. In this work, the spatial and temporal characteristics of X-pinch HXR emission are studied, the specific features of HXR generation are discussed, and the capability of applying this radiation to point-projection X-ray imaging of various plasma and biological objects is considered. The parameters of the electron beam produced in the X-pinch are measured using a Faraday cup and X-ray diagnostics. The experiments were performed with the XP generator (550 kA, 100 ns) at Cornell University (United States) and the BIN generator (270 kA, 150 ns) at the Lebedev Physical Institute (Russia).

  5. Solution Phase Molecular Dynamics Probed with Synchrotron Hard X-rays

    NASA Astrophysics Data System (ADS)

    March, Anne; Doumy, Gilles; Kanter, Elliot; Southworth, Stephen; Young, Linda; Nemeth, Zoltan; Vankó, Gyorgy; Assefa, Tadesse; Gawelda, Wojciech

    2013-05-01

    The ability to measure short-lived transient states during a chemical reaction is key to understanding many important processes such as oxygen binding in hemeproteins and electron transport in photosynthesis. Time resolved hard x-ray spectroscopies, which are based on laser-pump/x-ray-probe methods, are a unique tool because unlike UV-VIS techniques they are element specific and can provide electronic and structural information with atomic resolution in the vicinity of a particular atom or ion. These characteristics make them particularly powerful for studying molecules in complex environments such as solutions. Using a MHz, picosecond, high average power laser system implemented at Sector 7ID-D of the Advanced Photon Source we have been developing time resolved x-ray emission techniques to track the evolution of photoexcited molecules in solution. We will present recent studies which include the ligand substitution reaction and hydrated electron formation in the coordination complex ferrocyanide Fe(CN)64-. This work was supported by the Chemical Sciences, Geosciences, and Biosciences Division and the Advanced Photon Source by the Office of Basic Energy Sciences, Office of Science, US Dept of Energy, Contract DE-AC02-06CH11357.

  6. MULTIPLE PLASMOID EJECTIONS AND ASSOCIATED HARD X-RAY BURSTS IN THE 2000 NOVEMBER 24 FLARE

    SciTech Connect

    Nishizuka, N.; Takasaki, H.; Shibata, K.; Asai, A.

    2010-03-10

    The Soft X-ray Telescope (SXT) on board Yohkoh revealed that the ejection of X-ray emitting plasmoid is sometimes observed in a solar flare. It was found that the ejected plasmoid is strongly accelerated during a peak in the hard X-ray (HXR) emission of the flare. In this paper, we present an examination of the GOES X 2.3 class flare that occurred at 14:51 UT on 2000 November 24. In the SXT images, we found 'multiple' plasmoid ejections with velocities in the range of 250-1500 km s{sup -1}, which showed blob-like or loop-like structures. Furthermore, we also found that each plasmoid ejection is associated with an impulsive burst of HXR emission. Although some correlation between plasmoid ejection and HXR emission has been discussed previously, our observation shows similar behavior for multiple plasmoid ejection such that each plasmoid ejection occurs during the strong energy release of the solar flare. As a result of temperature-emission measure analysis of such plasmoids, it was revealed that the apparent velocities and kinetic energies of the plasmoid ejections show a correlation with the peak intensities in the HXR emissions.

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

    PubMed Central

    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.

    2011-01-01

    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. PMID:22355576

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

    SciTech Connect

    Takano, Hidekazu Konishi, Shigeki; Shimomura, Sho; Azuma, Hiroaki; Tsusaka, Yoshiyuki; Kagoshima, Yasushi

    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.

  9. The Hard X-ray experiment on the Astronomical Netherlands Satellite

    NASA Technical Reports Server (NTRS)

    Gursky, H.; Schnopper, H.; Parsignault, D.

    1975-01-01

    The Hard X-ray Experiment flown on the Astronomical Netherlands Satellite is described. The instrument consists of two parts. One is a large-area detector of about 60 sq cm in total area, sensitive in the energy range between 1.5 and 30 keV. Two counters comprise this detector, each collimated 10 min by 3 deg and offset in the narrow direction by 4 min. The other part is a Bragg-crystal assembly consisting of two PET crystals and counters aligned to search for the silicon emission lines near 2 keV. Instrument characteristics and orbital operations are described.

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

    DOEpatents

    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.

  11. Hard-x-ray microscopy with Fresnel zone plates reaches 40 nm Rayleigh resolution

    SciTech Connect

    Chu, Y. S.; Yi, J. M.; De Carlo, F.; Shen, Q.; Lee, Wah-Keat; Wu, H. J.; Wang, C. L.; Wang, J. Y.; Liu, C. J.; Wang, C. H.; Wu, S. R.; Chien, C. C.; Hwu, Y.; Tkachuk, A.; Yun, W.; Feser, M.; Liang, K. S.; Yang, C. S.; Je, J. H.; Margaritondo, G.

    2008-03-10

    Substantial improvements in the nanofabrication and characteristics of gold Fresnel zone plates yielded unprecedented resolution levels in hard-x-ray microscopy. Tests performed on a variety of specimens with 8-10 keV photons demonstrated a first-order lateral resolution below 40 nm based on the Rayleigh criterion. Combined with the use of a phase contrast technique, this makes it possible to view features in the 30 nm range; good-quality images can be obtained at video rate, down to 50 ms/frame. The important repercussions on materials science, nanotechnology, and the life sciences are discussed.

  12. Nanoscale zoom tomography with hard x rays using Kirkpatrick-Baez optics

    SciTech Connect

    Mokso, R.; Cloetens, P.; Maire, E.; Ludwig, W.; Buffiere, J.-Y.

    2007-04-02

    To overcome the limitations in terms of spatial resolution and field of view of existing tomography techniques, a hard x-ray projection microscope is realized based on the sub-100-nm focus produced by Kirkpatrick-Baez optics. The sample is set at a small distance downstream of the focus and Fresnel diffraction patterns with variable magnification are recorded on a medium-resolution detector. While the approach requires a specific phase retrieval procedure and correction for mirror imperfections, it allows zooming nondestructively into bulky samples. Quantitative three-dimensional nanoscale microscopy is demonstrated on an aluminum alloy in local tomography mode.

  13. Single-Grid-Pair Fourier Telescope for Imaging in Hard-X Rays and gamma Rays

    NASA Technical Reports Server (NTRS)

    Campbell, Jonathan

    2008-01-01

    This instrument, a proposed Fourier telescope for imaging in hard-x rays and gamma rays, would contain only one pair of grids made of an appropriate radiation-absorpting/ scattering material, in contradistinction to multiple pairs of such as grids in prior Fourier x- and gamma-ray telescopes. This instrument would also include a relatively coarse gridlike image detector appropriate to the radiant flux to be imaged. Notwithstanding the smaller number of grids and the relative coarseness of the imaging detector, the images produced by the proposed instrument would be of higher quality.

  14. HEAO 1 hard X-ray observations of three Abell clusters of galaxies

    NASA Technical Reports Server (NTRS)

    Rephaeli, Y.; Gruber, D. E.; Rothschild, R. E.

    1987-01-01

    The results of an analysis of the HEAO 1 hard X-ray measurements of the Coma, A1367, and A2319 galactic clusters are presented. All three clusters have been observed to have diffuse, extended radio emission in their central regions. The results are analyzed together with radio measurements to determine the energetic electron density and the strength of the mean intracluster magnetic field in these clusters. The results show that there is no clear evidence for nonthermal flux in the spectra of the three clusters at the sensitivity limit of the low energy detectors used.

  15. Long term temporal variations of the hard X-ray flux from the Centaurus region

    NASA Technical Reports Server (NTRS)

    Schwartz, D. A.; Peterson, L. E.; Hudson, H. S.

    1971-01-01

    The X-ray telescope aboard the third Orbiting Solar Observatory (OSO-3) observed the Centaurus region daily from 1967 October to 1968 February, and also for five days in 1968 June. A stable minimum flux of 0.33 + or - 0.03 photons (sq cm sec)/1 between 7.7 and 38 keV from a source around l = 305 deg is derived. Several single days show enhanced fluxes, and two extensive flaring episodes, one with a soft and the other a very hard spectrum, lasting at least ten days.

  16. Projection phase contrast microscopy with a hard x-ray nanofocused beam: Defocus and contrast transfer

    SciTech Connect

    Salditt, T.; Giewekemeyer, K.; Fuhse, C.; Krueger, S. P.; Tucoulou, R.; Cloetens, P.

    2009-05-01

    We report a projection phase contrast microscopy experiment using hard x-ray pink beam undulator radiation focused by an adaptive mirror system to 100-200 nm spot size. This source is used to illuminate a lithographic test pattern with a well-controlled range of spatial frequencies. The oscillatory nature of the contrast transfer function with source-to-sample distance in this holographic imaging scheme is quantified and the validity of the weak phase object approximation is confirmed for the experimental conditions.

  17. High resolution hard X-ray spectra of solar and cosmic sources. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Schwartz, R. A.

    1984-01-01

    High resolution hard X-ray observations of a large solar flare and the Crab Nebula were obtained during balloon flights using an array of cooled germanium planar detectors. In addition, high time resolution high sensitivity measurements were obtained with a 300 square cm NaI/CsI phoswich scintillator. The Crab spectrum from both flights was searched without finding evidence of line emission below 200 keV. In particular, for the 73 keV line previously reported a 3 sigma upper limit for a narrow (1 keV FWHM) line .0019 and .0014 ph square cm/sec for the 1979 and 1980 flights, respectively was obtained.

  18. Metal nanoplasmas as bright sources of hard X-ray pulses.

    PubMed

    Rajeev, P P; Taneja, P; Ayyub, P; Sandhu, A S; Kumar, G Ravindra

    2003-03-21

    We report significant enhancements in light coupling to intense-laser-created solid plasmas via surface plasmon and "lightning rod" effects. We demonstrate this in metal nanoparticle-coated solid targets irradiated with 100 fs, 806 nm laser pulses, focused to intensities approximately 10(14)-10(15) W cm(-2). Our experiments show a 13-fold enhancement in hard x-ray yield (10-200 keV) emitted by copper nanoparticle plasmas formed at the focal volume. A simple model explains the observed enhancement quantitatively and provides pointers to the design of structured surfaces for maximizing such emissions. PMID:12688936

  19. Calculation of Ar photoelectron satellites in the hard-x-ray region

    NASA Astrophysics Data System (ADS)

    Yarzhemsky, V. G.; Amusia, M. Ya.

    2016-06-01

    The intensities of photoelectron satellite lines, corresponding to the double core hole (DCH) states of Ar 1 s ionization by hard x rays, are calculated using the many-body perturbation theory. Calculations support the interpretation of the most intense lines as the shake-up excitations 2 p →4 p . It is demonstrated that the intensities of the spectrum lines corresponding to 4 s (and 3 d ) excited states in the DCH field can be explained only taking into account the knock-up process 2 p →3 d along with the shake-up process 1 s →4 s that accompanies 2 p photoionization.

  20. Prospects of hard X-ray polarimetry with Astrosat-CZTI

    NASA Astrophysics Data System (ADS)

    Chattopadhyay, T.; Vadawale, S. V.; Rao, A. R.; Sreekumar, S.; Bhattacharya, D.

    2014-11-01

    Astrosat is the first Indian satellite mission dedicated for astronomical studies. It is planned for launch during 2014 and will have five instruments for multi-wavelength observations from optical to hard X-rays. Cadmium Zing Telluride Imager (CZTI) is one of the five instruments aiming for simultaneous X-ray spectroscopy and imaging in the energy range of 10 keV to 100 keV (along with all sky photometric capability unto 250 keV). It is based on pixilated CZT detector array with total geometric area of 1024 cm2. It will have two-dimensional coded mask for medium resolution X-ray imaging. The CZT detector plane will be realized using CZT detector modules having integrated readout electronics. Each CZT detector module consists of 4 cm × 4 cm CZT with thickness of 5 mm which is further pixilated into 16 × 16 array of pixels. Thus each pixel has size of 2.5 mm × 2.5 mm and thickness of 5 mm. Such pixilated detector plane can in principle be used for hard X-ray polarization measurements based on the principle of Compton scattering by measuring azimuthal distribution of simultaneous events in two adjacent pixels. We have carried out detailed Geant4 simulations for estimating polarimetric capabilities of CZTI detector plane. The results indicate that events in the energy range of 100 keV to 250 keV, where the 5 mm thick CZT detector has significant detection efficiency, can be used for polarimetric studies. Our simulation results indicate the minimum detectable polarization (MDP) at the level of ˜ 10% can be achieved for bright Crab like X-ray sources with exposure time of ˜500 ks. We also carried out preliminary experiments to verify the results from our simulations. Here we present detailed method and results of our simulations as well as preliminary results from the experimental verification of polarimetric capabilities of CZT detector modules used in Astrosat CZTI.