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Sample records for hard x-ray timing

  1. Achieving few-femtosecond time-sorting at hard X-ray free-electron lasers

    Science.gov (United States)

    Harmand, M.; Coffee, R.; Bionta, M. R.; Chollet, M.; French, D.; Zhu, D.; Fritz, D. M.; Lemke, H. T.; Medvedev, N.; Ziaja, B.; Toleikis, S.; Cammarata, M.

    2013-03-01

    Recently, few-femtosecond pulses have become available at hard X-ray free-electron lasers. Coupled with the available sub-10 fs optical pulses, investigations into few-femtosecond dynamics are not far off. However, achieving sufficient synchronization between optical lasers and X-ray pulses continues to be challenging. We report a `measure-and-sort' approach, which achieves sub-10 fs root-mean-squared (r.m.s.) error measurement at hard X-ray FELs, far beyond the 100-200 fs r.m.s. jitter limitations. This timing diagnostic, now routinely available at the Linac Coherent Light Source (LCLS), is based on ultrafast free-carrier generation in optically transparent materials. Correlation between two independent measurements enables unambiguous demonstration of ~6 fs r.m.s. error in reporting the optical/X-ray delay, with single shot error suggesting the possibility of reaching few-femtosecond resolution.

  2. Subgroup report on hard x-ray microprobes

    International Nuclear Information System (INIS)

    Ice, G.E.; Barbee, T.; Bionta, R.; Howells, M.; Thompson, A.C.; Yun, W.

    1994-01-01

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

  3. Time Delays Between Decimetric Type-Iii Bursts and Associated Hard X-Rays

    Science.gov (United States)

    Sawant, H. S.; Lattari, C. J. B.; Benz, A. O.; Dennis, B. R.

    1990-11-01

    RESUMEN. En julio de 1987, se efectuaron radio observaciones en 1.6 CHz usando la antena de 13.7-m de Itapetinga con un tiempo de resoluci5n de 3 ms. Las observaciones en rayos-X fueron obtenidas del HXRBS en SMM. Comparaciones de observaciones de 1.6 CHz con espectro dinamico en el intervalo de (1000 - 100) MHz y rayos-X duros muestran los siguientes resultados: I) en 12 casos, identificamos la continuaci6n de brotes de tipo Ill-RD hasta 1.6 GHz. ii) Por primera vez, hemos identificadopicos de rayos-X demorados en comparaci6n con el brote decimetrico tipolll-RD. Estos retardos son mas largos - 1 5 - que lo esperado ( " 100 ms) y han sido interpretados suponiendo que la emisi6n decimetrica es la 2a. ar- m6nica y esta causada por el borde delantero del excitador, mientras que los picos de los rayos-X han sido atribuidos a la entrada completa del excitador dentro de la regi6n que produce los rayos-X. ABSTRACT. In July, 1985 radio observations were made at 1.6 GHz using 13.7 m Itapetinga antenna with time resolution of 3 ms. The hard X-ray observations were obtained from HXRBS on SMM. Comparison of 1.6 GHz observations with dynamic spectra in the frequency range of (1000 - 100) MHz and hard X-rays shows the following results: i) In 12 cases, we identify continuation of type Ill-RD bursts up to 1.6 GHz suggesting presence of type Ill-RD bursts at 1.6 GHz. ii) For the first time, we have idetified hard X-ray peaks delayed in comparison to decimetric type Ill-RD bursts. These dalays are longer - 1 5 - than expected ( 100 ms) and have been interpreted assuming that the decimetric emission is at 2 nd harmonic and caused by the leading edge of the exciter, whereas peaks of X-rays have been attributed to entire entry of the exciter into the X-ray producing region. Keq : SUN BURSTS - SUN-

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

    International Nuclear Information System (INIS)

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

    2006-01-01

    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 μm 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

  5. Broad-band hard X-ray reflectors

    DEFF Research Database (Denmark)

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

    1997-01-01

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

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

    Science.gov (United States)

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

    2012-10-01

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

  7. Effective high voltage at X-ray tube in hard X-ray chest imaging

    International Nuclear Information System (INIS)

    Klein, J.

    1987-01-01

    The FRG standard TGL 36 661 (March 1980) for synoptical chest pictures of large size in adults specifies the 120 kV voltage at the X-ray tube together with maximal, 100% use of the capacity of the tube (hard picture, short exposure time). By means of circular recording and by measuring the high voltage at the X-ray tube it was quantitatively shown that the effective voltage during exposure is (according to the exposure time and the attenuation phase of the generator) always lower than the set-up voltage of 120 kV. This phenomenon is the more marked the shorter the actual exposure time in comparison with the attenuation phase of the generator. The typical characteristic of a hard X-ray chest picture is thus not given only by the setting-up of voltage. The impact of the reduction in voltage is thus quantitatively shown also from the aspect of the radiation burden for the patient. (author). 7 figs., 8 refs

  8. Time-resolved hard x-ray studies using third-generation synchrotron radiation sources (abstract)

    International Nuclear Information System (INIS)

    Mills, D.M.

    1992-01-01

    The third-generation, high-brilliance, synchrotron radiation sources currently under construction will usher in a new era of x-ray research in the physical, chemical, and biological sciences. One of the most exciting areas of experimentation will be the extension of static x-ray scattering and diffraction techniques to the study of transient or time-evolving systems. The high repetition rate, short-pulse duration, high-brilliance, variable spectral bandwidth, and large particle beam energies of these sources make them ideal for hard x-ray, time-resolved studies. The primary focus of this presentation will be on the novel instrumentation required for time-resolved studies such as optics which can increase the flux on the sample or disperse the x-ray beam, detectors and electronics for parallel data collection, and methods for altering the natural time structure of the radiation. This work is supported by the U.S. Department of Energy, BES-Materials Science, under Contract No. W-31-109-ENG-38

  9. Hard X-ray mirrors for Nuclear Security

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-01-07

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

  10. Time-Resolved Hard X-Ray Spectrometer

    International Nuclear Information System (INIS)

    Kenneth Moya; Ian McKennaa; Thomas Keenana; Michael Cuneob

    2007-01-01

    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

  11. The Emerging Population of Pulsar Wind Nebulae in Hard X-rays

    Science.gov (United States)

    Mattana, F.; Götz, D.; Terrier, R.; Renaud, M.; Falanga, M.

    2009-05-01

    The hard X-ray synchrotron emission from Pulsar Wind Nebulae probes energetic particles, closely related to the pulsar injection power at the present time. INTEGRAL has disclosed the yet poorly known population of hard X-ray pulsar/PWN systems. We summarize the properties of the class, with emphasys on the first hard X-ray bow-shock (CTB 80 powered by PSR B1951+32), and highlight some prospects for the study of Pulsar Wind Nebulae with the Simbol-X mission.

  12. Hard X-ray imaging with a slat collimated telescope

    International Nuclear Information System (INIS)

    Lu Zhuguo; Kotov, Yu.D.; Suslov, A.Yu.

    1995-01-01

    Imaging experiments with a slat collimated hard X-ray telescope are described in this paper demonstrating the feasibility of the direct demodulation imaging method used in hard X-ray scanning modulation experiments. On 25 September 1993 an X-ray raster scan observation of Cyg X-1 was performed in a balloon flight with the hard X-ray telescope HAPI-4. An experiment to image radioactive X-ray sources was performed in the laboratory before. In both experiments the expected X-ray images were obtained, confirming the imaging capability of this method. (orig.)

  13. Hard X-ray Microscopic Imaging Of Human Breast Tissues

    Science.gov (United States)

    Park, Sung H.; Kim, Hong T.; Kim, Jong K.; Jheon, Sang H.; Youn, Hwa S.

    2007-01-01

    X-ray microscopy with synchrotron radiation will be a useful tool for innovation of x-ray imaging in clinical and laboratory settings. It helps us observe detailed internal structure of material samples non-invasively in air. And, it also has the potential to solve some tough problems of conventional breast imaging if it could evaluate various conditions of breast tissue effectively. A new hard x-ray microscope with a spatial resolution better than 100 nm was installed at Pohang Light Source, a third generation synchrotron radiation facility in Pohang, Korea. The x-ray energy was set at 6.95 keV, and the x-ray beam was monochromatized by W/B4C monochromator. Condenser and objective zone plates were used as x-ray lenses. Zernike phase plate next to condenser zone plate was introduced for improved contrast imaging. The image of a sample was magnified 30 times by objective zone plate and 20 times by microscope objective, respectively. After additional 10 times digital magnification, the total magnifying power was up to 6000 times in the end. Phase contrast synchrotron images of 10-μm-thick female breast tissue of the normal, fibroadenoma, fibrocystic change and carcinoma cases were obtained. By phase contrast imaging, hard x-rays enable us to observe many structures of breast tissue without sample preparations such as staining or fixation.

  14. Hard X-ray Microscopic Imaging Of Human Breast Tissues

    International Nuclear Information System (INIS)

    Park, Sung H.; Kim, Hong T.; Kim, Jong K.; Jheon, Sang H.; Youn, Hwa S.

    2007-01-01

    X-ray microscopy with synchrotron radiation will be a useful tool for innovation of x-ray imaging in clinical and laboratory settings. It helps us observe detailed internal structure of material samples non-invasively in air. And, it also has the potential to solve some tough problems of conventional breast imaging if it could evaluate various conditions of breast tissue effectively. A new hard x-ray microscope with a spatial resolution better than 100 nm was installed at Pohang Light Source, a third generation synchrotron radiation facility in Pohang, Korea. The x-ray energy was set at 6.95 keV, and the x-ray beam was monochromatized by W/B4C monochromator. Condenser and objective zone plates were used as x-ray lenses. Zernike phase plate next to condenser zone plate was introduced for improved contrast imaging. The image of a sample was magnified 30 times by objective zone plate and 20 times by microscope objective, respectively. After additional 10 times digital magnification, the total magnifying power was up to 6000 times in the end. Phase contrast synchrotron images of 10-μm-thick female breast tissue of the normal, fibroadenoma, fibrocystic change and carcinoma cases were obtained. By phase contrast imaging, hard x-rays enable us to observe many structures of breast tissue without sample preparations such as staining or fixation

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

    Science.gov (United States)

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

    2005-12-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-12-20

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

  17. Hard X-ray studies on the Castor tokamak

    International Nuclear Information System (INIS)

    Mlynar, J.

    1990-04-01

    The electron runaway processes in tokamaks are discussed with regard to hard X radiation measurements. The origin and confinement of runaway electrons, their bremsstrahlung spectra and the influence of lower hybrid current drive on the distribution of high-energy electrons are analyzed for the case of the Castor tokamak. The hard X-ray spectrometer designed for the Castor tokamak is also described and preliminary qualitative results of hard X-ray measurements are presented. The first series of integral measurements made it possible to map the azimuthal dependence of the hard X radiation

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

    International Nuclear Information System (INIS)

    Yu, W.

    2004-01-01

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

  19. NuSTAR Hard X-ray Survey of the Galactic Center Region. I. Hard X-ray Morphology and Spectroscopy of the Diffuse Emission

    DEFF Research Database (Denmark)

    Mori, Kaya; Hailey, Charles J.; Krivonos, Roman

    2015-01-01

    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). Nu...

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

    Science.gov (United States)

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

    2009-05-01

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

  1. Multi-spacecraft observations of solar hard X-ray bursts

    International Nuclear Information System (INIS)

    Kane, S.R.

    1981-01-01

    The role of multi-spacecraft observations in solar flare research is examined from the point of view of solar hard X-ray bursts and their implications with respect to models of the impulsive phase. Multi-spacecraft measurements provide a stereoscopic view of the flare region, and hence represent the only direct method of measuring directivity of X-rays. In absence of hard X-ray imaging instruments with high spatial and temporal resolution, multi-spacecraft measurements provide the only means of determining the radial (vertical) structure of the hard X-ray source. This potential of the multi-spacecraft observations is illustrated with an analysis of the presently available observations of solar hard X-ray bursts made simultaneously by two or more of the following spacecraft: International Sun Earth Explorer-3 (ISEE-3), Pioneer Venus Orbiter (PVO), Helios-B and High Energy Astrophysical Observatory-A (HEAO-A). In particular, some conclusions have been drawn about the spatial structure and directivity of 50-100 keV X-rays from impulsive flares. Desirable features of future multi-spacecraft missions are briefly discussed followed by a short description of the hard X-ray experiment on the International Solar Polar Mission which has been planned specifically for multi-spacecraft observations of the Sun. (orig.)

  2. Coherent hard x-ray focusing optics and applications

    Energy Technology Data Exchange (ETDEWEB)

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

    1991-01-01

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

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

    International Nuclear Information System (INIS)

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

    1983-06-01

    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

  4. Characteristics of hard X-ray double sources in impulsive solar flares

    Science.gov (United States)

    Sakao, T.; Kosugi, T.; Masuda, S.; Yaji, K.; Inda-Koide, M.; Makishima, K.

    1996-01-01

    Imaging observations of solar flare hard X-ray sources with the Hard X-ray Telescope (HXT) aboard the Yohkoh satellite have revealed that hard X-ray emissions (greater than 30 ke V) originate most frequently from double sources. The double sources are located on both sides of the magnetic neutral line, suggesting that the bulk of hard X-rays is emitted from footpoints of flaring magnetic loops. We also found that hard X-rays from the double sources are emitted simultaneously within a fraction of second and that the weaker source tends to be located in the stronger magnetic field region, showing a softer spectrum. Physcial implications on the observed characteristics of the hard X-ray double sources are discussed.

  5. Solar flare hard and soft x ray relationship determined from SMM HXRBS and BCS data

    Science.gov (United States)

    Toot, G. David

    1989-01-01

    The exact nature of the solar flare process is still somewhat a mystery. A key element to understanding flares if the relationship between the hard x rays emitted by the most energetic portions of the flare and the soft x rays from other areas and times. This relationship was studied by comparing hard x ray light curved from the Hard X-Ray Burst Spectrometer (HXRBS) with the soft x ray light curve and its derivation from the Bent Crystal Spectrometer (BCS) which is part of the X-Ray Polychrometer (XRP), these instruments being on the Solar Maximum Mission spacecraft (SMM). Data sample was taken from flares observed with the above instruments during 1980, the peak of the previous maximum of solar activity. Flares were chosen based on complete coverage of the event by several instruments. The HXRBS data covers the x ray spectrum from about 25 keV to about 440 keV in 15 spectral channels, while the BCS data used covers a region of the Spectrum around 3 angstroms including emission from the Ca XIX ion. Both sets of data were summed over their spectral ranges and plotted against time at a maximum time resolution of around 3 seconds. The most popular theory of flares holds that a beam of electrons produces the hard x rays by bremsstrahlung while the soft x rays are the thermal response to this energy deposition. The question is whether the rate of change of soft x ray emission might reflect the variability of the electron beam and hence the variability of the hard x rays. To address this, we took the time derivative of the soft x ray light curve and compared it to the hard flares, 12 of them showed very closed agreement between the soft x ray derivative and the hard x ray light curve. The other five did not show this behavior but were similar to each other in general soft x ray behavior. Efforts to determine basic differences between the two kinds of flares continue. In addition the behavior of soft x ray temperature of flares was examined.

  6. Time resolved, 2-D hard X-ray imaging of relativistic electron-beam target interactions on ETA-II

    International Nuclear Information System (INIS)

    Crist, C.E.; Sampayan, S.; Westenskow, G.; Caporaso, G.; Houck, T.; Weir, J.; Trimble, D.; Krogh, M.

    1998-01-01

    Advanced radiographic applications require a constant source size less than 1 mm. To study the time history of a relativistic electron beam as it interacts with a bremsstrahlung converter, one of the diagnostics they use is a multi-frame time-resolved hard x-ray camera. They are performing experiments on the ETA-II accelerator at Lawrence Livermore National Laboratory to investigate details of the electron beam/converter interactions. The camera they are using contains 6 time-resolved images, each image is a 5 ns frame. By starting each successive frame 10 ns after the previous frame, they create a 6-frame movie from the hard x-rays produced from the interaction of the 50-ns electron beam pulse

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

    Energy Technology Data Exchange (ETDEWEB)

    Winarski, Robert P., E-mail: winarski@anl.gov; Holt, Martin V. [Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60441 (United States); Rose, Volker [Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60441 (United States); Fuesz, Peter; Carbaugh, Dean; Benson, Christa; Shu, Deming; Kline, David; Stephenson, G. Brian; McNulty, Ian [Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60441 (United States); Maser, Jörg [Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60441 (United States)

    2012-11-01

    The Hard X-ray Nanoprobe Beamline is a precision platform for scanning probe and full-field microscopy with 3–30 keV X-rays. A combination of high-stability X-ray optics and precision motion sensing and control enables detailed studies of the internal features of samples with resolutions approaching 30 nm. 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.

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

    International Nuclear Information System (INIS)

    Wang Wei

    2009-01-01

    Recent INTEGRAL/IBIS hard X-ray surveys have detected about 10 young pulsars. We show hard X-ray properties of these 10 young pulsars, which have a luminosity of 10 33 -10 37 erg s -1 and a photon index of 1.6-2.1 in the energy range of 20-100 keV. The correlation between X-ray luminosity and spin-down power of L X ∝ L sd 1.31 suggests that the hard X-ray emission in rotation-powered pulsars is dominated by the pulsar wind nebula (PWN) component. Assuming spectral properties are similar in 20-100 keV and 2-10 keV for both the pulsar and PWN components, the hard X-ray luminosity and flux of 39 known young X-ray pulsars and 8 millisecond pulsars are obtained, and a correlation of L X ∝ L sd 1.5 is derived. About 20 known young X-ray pulsars and 1 millisecond pulsars could be detected with future INTEGRAL and HXMT surveys. We also carry out Monte Carlo simulations of hard X-ray pulsars in the Galaxy and the Gould Belt, assuming values for the pulsar birth rate, initial position, proper motion velocity, period, and magnetic field distribution and evolution based on observational statistics and the L X - L sd relations: L X ∝ L sd 1.31 and L X ∝ L sd 1.5 . More than 40 young pulsars (mostly in the Galactic plane) could be detected after ten years of INTEGRAL surveys and the launch of HXMT. So, the young pulsars would be a significant part of the hard X-ray source population in the sky, and will contribute to unidentified hard X-ray sources in present and future hard X-ray surveys by INTEGRAL and HXMT.

  9. CORRELATION OF HARD X-RAY AND WHITE LIGHT EMISSION IN SOLAR FLARES

    Energy Technology Data Exchange (ETDEWEB)

    Kuhar, Matej; Krucker, Säm; Battaglia, Marina; Kleint, Lucia; Casadei, Diego [University of Applied Sciences and Arts Northwestern Switzerland, Bahnhofstrasse 6, 5210 Windisch (Switzerland); Oliveros, Juan Carlos Martinez; Hudson, Hugh S. [Space Sciences Laboratory, University of California, Berkeley, CA 94720-7450 (United States)

    2016-01-01

    A statistical study of the correlation between hard X-ray and white light emission in solar flares is performed in order to search for a link between flare-accelerated electrons and white light formation. We analyze 43 flares spanning GOES classes M and X using observations from the Reuven Ramaty High Energy Solar Spectroscopic Imager and Helioseismic and Magnetic Imager. We calculate X-ray fluxes at 30 keV and white light fluxes at 6173 Å summed over the hard X-ray flare ribbons with an integration time of 45 s around the peak hard-X ray time. We find a good correlation between hard X-ray fluxes and excess white light fluxes, with a highest correlation coefficient of 0.68 for photons with energy of 30 keV. Assuming the thick target model, a similar correlation is found between the deposited power by flare-accelerated electrons and the white light fluxes. The correlation coefficient is found to be largest for energy deposition by electrons above ∼50 keV. At higher electron energies the correlation decreases gradually while a rapid decrease is seen if the energy provided by low-energy electrons is added. This suggests that flare-accelerated electrons of energy ∼50 keV are the main source for white light production.

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

    Science.gov (United States)

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

    1993-01-01

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

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

    Science.gov (United States)

    Markowitz, Alex Gary

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

  12. Prospects for supermirrors in hard x-ray spectroscopy

    DEFF Research Database (Denmark)

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

    1994-01-01

    . The measured x-ray reflectivities are well accounted for by the standard dynamical theories of multilayer reflection. Hard x ray applications that could benefit from x-ray supermirror coatings include focusing and imaging instrumentation for astrophysics, collimating and focusing devices for synchrotron...

  13. Hard X-ray Photoelectric Polarimeter

    Data.gov (United States)

    National Aeronautics and Space Administration — Our objective is to determine the gas mixtures and pressures that would enable a sensitive, hard X-ray polarimeter using existing flight components with the goal of...

  14. X-Ray Timing Analysis of Cyg X-3 Using AstroSat/LAXPC: Detection of Milli-hertz Quasi-periodic Oscillations during the Flaring Hard X-Ray State

    Energy Technology Data Exchange (ETDEWEB)

    Pahari, Mayukh; Misra, Ranjeev [Inter-University Center for Astronomy and Astrophysics, Ganeshkhind, Pune 411007 (India); Antia, H M; Yadav, J S; Chauhan, Jai Verdhan; Chitnis, V R; Dedhia, Dhiraj; Katoch, Tilak; Madhwani, P; Shah, Parag [Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005 (India); Agrawal, P C [UM-DAE Center of Excellence for Basic Sciences, University of Mumbai, Kalina, Mumbai 400098 (India); Manchanda, R K [University of Mumbai, Kalina, Mumbai 400098 (India); Paul, B, E-mail: mayukh@iucaa.in [Department of Astronomy and Astrophysics, Raman Research Institute, Bengaluru 560080 (India)

    2017-11-01

    We present here results from the X-ray timing and spectral analysis of the X-ray binary Cyg X-3 using observations from the Large Area X-ray proportional Counter on board AstroSat . Consecutive light curves observed over a period of one year show the binary orbital period of 17253.56 ± 0.19 s. Another low-amplitude, slow periodicity of the order of 35.8 ± 1.4 days is observed, which may be due to the orbital precession as suggested earlier by Molteni et al. During the rising binary phase, power density spectra from different observations during the flaring hard X-ray state show quasi-periodic oscillations (QPOs) at ∼5–8 mHz, ∼12–14 mHz, and ∼18–24 mHz frequencies at the minimum confidence of 99%. However, during the consecutive binary decay phase, no QPO is detected up to 2 σ significance. Energy-dependent time-lag spectra show soft lag (soft photons lag hard photons) at the mHz QPO frequency and the fractional rms of the QPO increases with the photon energy. During the binary motion, the observation of mHz QPOs during the rising phase of the flaring hard state may be linked to the increase in the supply of the accreting material in the disk and corona via stellar wind from the companion star. During the decay phase, the compact source moves in the outer wind region causing the decrease in supply of material for accretion. This may cause weakening of the mHz QPOs below the detection limit. This is also consistent with the preliminary analysis of the orbital phase-resolved energy spectra presented in this paper.

  15. The over-the-limb hard X-ray events

    Science.gov (United States)

    Hudson, H. S.

    Over-the-limb hard X-ray events offer a uniquely direct view of the hard X-ray emission from the solar corona during a major flare. Limb occultation at angles greater than about 10 deg (an arbitrary definition of this class of events) excludes any confusion with brighter chromospheric sources. Published observations of seven over-the-limb events, beginning with the prototype flare of March 30, 1969, are reviewed. The hard X-ray spectra appear to fall into two classes: hard events, with power-law index of about 2.0; and soft events, with power-law index about 5.4. This tendency towards bimodality is only significant at the 90-percent confidence level due to the smallness of the number of events observed to date. If borne out by future data, the bimodality would suggest the existence of two different acceleration mechanisms.

  16. Hard X-Ray PHA System on the HT-7 Tokamak

    International Nuclear Information System (INIS)

    Lin Shiyao; Shi Yuejiang; Wan Baonian; Chen Zhongyong; Hu Liqun

    2006-01-01

    A new hard X-ray pulse-height analysis (PHA) system has been established on HT-7 tokamak for long pulse steady-state operation. This PHA system consists of hard X-ray diagnostics and multi-channel analysers (MCA). The hard X-ray diagnostics consists of a vertical X-ray detector array (CdTe) and a horizontal X-ray detector array (NaI). The hard X-ray diagnostics can provide the profile of power deposition and the distribution function of fast electron during radio frequency (RF) current drive. The MCA system is the electronic part of the PHA system, which has been modularized and linked to PC through LAN. Each module of MCA can connect with 8 X-ray detectors. The embedded Ethernet adapter in the MCA module makes the data communication between PC and MCA very convenient. A computer can control several modules of MCA through certain software and a hub. The RAM in MCA can store 1024 or more spectra for each detector and therefore the PHA system can be applied in the long pulse discharge of several minutes

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-12-01

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

  18. Microfabrication of hard x-ray lenses

    DEFF Research Database (Denmark)

    Stöhr, Frederik

    This thesis deals with the development of silicon compound refractive lenses (Si-CRLs) for shaping hard x-ray beams. The CRLs are to be fabricated using state of the art microfabrication techniques. The primary goal of the thesis work is to produce Si-CRLs with considerably increased structure...... and characterized with respect to their shape. Their optical performances were tested at the European Synchrotron Radiation Facility (ESRF). Two 1D-focusing Si-CRLs suitable as condensers in hard-XRM were developed utilizing the aforementioned two different strategies. The first Si-condenser showed focusing of a 56...... of space for sample surroundings and ensure low-divergent and wide x-ray beams with narrow waists. Both results are substantial improvements to what was available at the start of this thesis work. The challenge of making x-ray objectives in silicon by interdigitation of lenslets alternately focusing...

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

    NARCIS (Netherlands)

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

    2004-01-01

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

  20. The hard X-ray spectrum of Cyg X-1 during the transition in November 1975

    International Nuclear Information System (INIS)

    Sommer, M.; Maurus, H.; Urbach, R.

    1976-01-01

    Some observations are reported of the hard X-ray spectrum of Cyg X-1 during a transition to the high state in November 1975, made with a balloon-borne X-ray detector. The range covered was 25 to 150 keV. The data obtained appeared to confirm the characteristic spectral time variation, and suggested a single power law spectrum from 3 to 80 keV, with an increasing spectral index during the upward transition to the high state. A power spectrum is expected if it is assumed that the universe Compton effect is the basic mechanism that produces the hard X-ray tail of Cyg X-1. Spectral time variation may be caused by a varying intensity of an inner soft photon source within a stable hot cloud. (U.K.)

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

    Energy Technology Data Exchange (ETDEWEB)

    Fein, J. R., E-mail: jrfein@umich.edu; Holloway, J. P. [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, Michigan 48109-2143 (United States); Peebles, J. L. [Center for Energy Research, University of California, San Diego, La Jolla, California 92093 (United States); Keiter, P. A.; Klein, S. R.; Kuranz, C. C.; Manuel, M. J.-E.; Drake, R. P. [Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, Ann Arbor, Michigan 48109-2143 (United States)

    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.

  2. Hard X-ray observation of HER X-1

    Energy Technology Data Exchange (ETDEWEB)

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

    1981-01-01

    A hard X-rays (15-170 KeV) measurement of the spectrum of Her X-1, during a mid turn-on is presented. The presence of an emission line at about 53 KeV during the mid-on state is confirmed by the present measure.

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

    International Nuclear Information System (INIS)

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

    2004-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2004-07-01

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

  5. Hard X-ray photoemission spectroscopy

    International Nuclear Information System (INIS)

    Kobayashi, Keisuke

    2009-01-01

    Except in the very early stage of the development of X-ray photoemission spectroscopy (XPS) by Kai Siegbahn and his coworkers, the excitation sources for XPS studies have predominantly been the Al Kα and Mg Kα emission lines. The advent of synchrotron radiation sources opened up the possibility of tuning the excitation photon energy with much higher throughputs for photoemission spectroscopy, however the excitation energy range was limited to the vacuum ultra violet and soft X-ray regions. Over the past 5-6 years, bulk-sensitive hard X-ray photoemission spectroscopy using high-brilliance high-flux X-rays from third generation synchrotron radiation facilities has been developed. This article reviews the history of HXPES covering the period from Kai Siegbahn and his coworkers' pioneering works to the present, and describes the fundamental aspects, instrumentation, applications to solid state physics, applied physics, materials science, and industrial applications of HXPES. Finally, several challenging new developments which have been conducted at SPring-8 by collaborations among several groups are introduced.

  6. Hard X-ray observation of HER X-1

    International Nuclear Information System (INIS)

    Ubertini, P.; Bazzano, A.; La Padula, C.; Polcaro, V.F.; Vialetto, G.

    1981-01-01

    A hard X-rays (15-170 KeV) measurement of the spectrum of Her X-1, during a mid turn-on is presented. The presence of an emission line at about 53 KeV during the mid-on state is confirmed by the present measure. (orig.)

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

    International Nuclear Information System (INIS)

    Bai, T.; Ramaty, R.

    1978-01-01

    Hard X-rays incident upon the photosphere with energies > or approx. =15 keV have high probabilities of backscatter due to Compton collisions with electrons. This effect has a strong influence on the spectrum, intensity, and polarization of solar hard X-rays - especially for anisotropic models in which the primary X-rays are emitted predominantly toward the photosphere. We have carried out a detailed study of X-ray backscatter, and we have investigated the interrelated problems of anisotropy, polarization, center-to-limb variation of the X-ray spectrum, and Compton backscatter in a coherent fashion. The results of this study are compared with observational data. Because of the large contribution from backscatter, for an anisotropic primary X-ray source which is due to bremsstrahlung of accelerated electrons moving predominantly down toward the photosphere, the observed X-ray flux around 30 keV does not depend significantly on the position of flare on the Sun. For such an anisotropic source, the X-ray spectrum observed in the 15-50 keV range becomes steeper with the increasing heliocentric angle of the flare. These results are compatible with the data. The degree of polarization of the sum of the primary and reflected X-rays with energies between about 15 and 30 keV can be very large for anisotropic primary X-ray sources, but it is less than about 4% for isotropic sources. We also discuss the characteristics of the brightness distribution of the X-ray albedo patch created by the Compton backscatter. The height and anisotropy of the primary hard X-ray source might be inferred from the study of the albedo patch

  8. Deducing Electron Properties from Hard X-Ray Observations

    Science.gov (United States)

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

    2011-01-01

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

  9. A hard X-ray laboratory for monochromator characterisation

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-04-01

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

  10. Short term variation of Cyg X-1 in the hard x-ray region

    International Nuclear Information System (INIS)

    Doi, Kosei

    1978-01-01

    Cyg X-1 is a peculiar celestial body considered to be a close binary system of a black hole and a blue super-giant star. It is presently known that the time fluctuation of Cyg X-1 is considerably complex, ranging from seconds to days or months. Of these variation, attention has been paid to the short time variation in relation to the black hole theory. Observations of fluctuations in the order of second have been limited to soft X-ray (20 keV or more) so far, because great technical difficulties are involved due to the low intensity of hard X-ray. The present investigation is based on the fluctuations in the order of second in hard X-ray, and was conducted by employing an unprecedented large area X-ray telescope. The text describes on the brief history of the short time fluctuation, explains the experimental plan, X-ray detecting system, flight of a balloon and the analyses and discussions of fluctuation factor by variation function method, and gives the analysis data and conclusion. The observations resulted in the fact that the fluctuations in the order of second were small at 20 to 30 keV, but become large when energy is higher or lower than this value. The most natural explanation available for this result may be that it is essentially spectrum fluctuation, being inverse correlation in higher and lower energies. Physical meaning of such spectrum fluctuation is considered in connection with precipitating disk model around a black hole. (Wakatsuki, Y.)

  11. Short term variation of Cyg X-1 in the hard x-ray region

    Energy Technology Data Exchange (ETDEWEB)

    Doi, Kosei [Tokyo Univ. (Japan). Inst. of Space and Aeronautical Science

    1978-08-01

    Cyg X-1 is a peculiar celestial body considered to be a close binary system of a black hole and a blue super-giant star. It is presently known that the time fluctuation of Cyg X-1 is considerably complex, ranging from seconds to days or months. Of these variation, attention has been paid to the short time variation in relation to the black hole theory. Observations of fluctuations in the order of second have been limited to soft X-ray (20 keV or more) so far, because great technical difficulties are involved due to the low intensity of hard X-ray. The present investigation is based on the fluctuations in the order of second in hard X-ray, and was conducted by employing an unprecedented large area X-ray telescope. The text describes on the brief history of the short time fluctuation, explains the experimental plan, X-ray detecting system, flight of a balloon and the analyses and discussions of fluctuation factor by variation function method, and gives the analysis data and conclusion. The observations resulted in the fact that the fluctuations in the order of second were small at 20 to 30 keV, but become large when energy is higher or lower than this value. The most natural explanation available for this result may be that it is essentially spectrum fluctuation, being inverse correlation in higher and lower energies. Physical meaning of such spectrum fluctuation is considered in connection with precipitating disk model around a black hole.

  12. Solar Coronal Events with Extended Hard X-ray and Gamma-ray Emission

    Science.gov (United States)

    Hudson, H. S.

    2017-12-01

    A characteristic pattern of solar hard X-ray emission, first identified in SOL1969-03-31 by Frost & Dennis (1971) now has been linked to prolonged high-energy gamma-ray emission detected by the Fermi/LAT experiment, for example in SOL2014-09-01. The distinctive features of these events include flat hard X-ray spectra extending well above 100 keV, a characteristic pattern of time development, low-frequency gyrosynchrotron peaks, CME association, and gamma-rays identifiable with pion decay originating in GeV ions. The identification of these events with otherwise known solar structures nevertheless remains elusive, in spite of the wealth of imagery available from AIA. The quandary is that these events have a clear association with CMEs in the high corona, and yet the gamma-ray production implicates the photosphere itself. The vanishingly small loss cone in the nominal acceleration region makes this extremely difficult. I propose direct inward advection of a part of the SEP particle population, as created on closed field structures, as a possible resolution of this puzzle, and note that this requires retracting magnetic structures on long time scales following the flare itself.

  13. The Hard X-ray Sky: Recent Observational Progress

    International Nuclear Information System (INIS)

    Gehrels, Neil; Cannizzo, John K.

    2009-01-01

    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.

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

    Science.gov (United States)

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

    2017-06-01

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

  15. Hard X-ray Emission and Efficient Particle Acceleration by Supernova Remnants

    International Nuclear Information System (INIS)

    Vink, Jacco

    2009-01-01

    I discuss the non-thermal X-ray emission from young supernova remnants. Over the last decade it has become clear from both X-ray and γ-ray observations that young supernovae accelerate particles up to 100 TeV. In soft X-rays the accelerated >10 TeV electrons produce synchrotron radiation, coming from narrow filaments located at the shock fronts. The width of these filaments shows that the magnetic fields are relatively high, thus providing evidence for magnetic field amplification.The synchrotron radiation of several remnants is known to extend into the hard X-ray regime. In particular Cas A, has a spectrum that appears as a power law up to almost 100 TeV. This is very surprising, as a steepening is expected going from the soft to the hard X-ray band. The spectrum is likely a result of many superimposed individual spectra, each steepening at different energies. This implies considerable spatial variation in hard X-rays, an obvious target for Simbol-X. The variations will be important to infer local shock acceleration properties, but also magnetic field fluctuations may cause spatial and temporal variations.Finally, I draw the attention to super bubbles and supernovae as sources of cosmic rays. As such they may be sources of hard X-ray emission. In particular, supernovae exploding inside the dense red supergiants winds of their progenitors ares promising candidates for hard X-ray emission.

  16. Hard X-ray Emission and Efficient Particle Acceleration by Supernova Remnants

    Science.gov (United States)

    Vink, Jacco

    2009-05-01

    I discuss the non-thermal X-ray emission from young supernova remnants. Over the last decade it has become clear from both X-ray and γ-ray observations that young supernovae accelerate particles up to 100 TeV. In soft X-rays the accelerated >10 TeV electrons produce synchrotron radiation, coming from narrow filaments located at the shock fronts. The width of these filaments shows that the magnetic fields are relatively high, thus providing evidence for magnetic field amplification. The synchrotron radiation of several remnants is known to extend into the hard X-ray regime. In particular Cas A, has a spectrum that appears as a power law up to almost 100 TeV. This is very surprising, as a steepening is expected going from the soft to the hard X-ray band. The spectrum is likely a result of many superimposed individual spectra, each steepening at different energies. This implies considerable spatial variation in hard X-rays, an obvious target for Simbol-X. The variations will be important to infer local shock acceleration properties, but also magnetic field fluctuations may cause spatial and temporal variations. Finally, I draw the attention to super bubbles and supernovae as sources of cosmic rays. As such they may be sources of hard X-ray emission. In particular, supernovae exploding inside the dense red supergiants winds of their progenitors ares promising candidates for hard X-ray emission.

  17. Rapid spectral and flux time variations in a solar burst observed at various dm-mm wavelengths and at hard x rays

    International Nuclear Information System (INIS)

    Zodivaz, A.M.; Kaufmann, P.; Correia, E.; Costa, J.E.R.; Takakura, T.; Cliver, E.W.; Tapping, K.F.; Air Force Geophysics Lab., Hanscom AFB, MA; National Research Council of Canada, Ottawa, Ontario)

    1986-01-01

    A solar burst was observed with high sensitivity and time resolution at cm-mm wavelengths by two different radio observatories (Itapetinga and Algonquin), with high spectral time resolution at dm-mm wavelengths by patrol instruments (Sagamore Hill), and at hard x rays (HXM Hinotori). At the onset of the major burst time structure there was a rapid rise in the spectral turnover frequency (from 5 to 15 GHz), in about 10s, coincident to a reduction of the spectral index in the optically thin part of the spectrum. The burst maxima were not time coincident at the optically thin radio frequencies and at the different hard x ray energy ranges. The profiles at higher radio frequencies exhibited better time coincidence to the high energy x rays. The hardest x ray spectrum (-3) coincided with peak radio emission at the higher frequency (44 GHz). The event appeared to be built up by a first major injection of softer particles followed by other injections of harder particles. Ultrafast time structures were identified as superimposed on the burst emission at the cm-mm high sensitivity data at x rays, with predominant repetition rates ranging from 2.0 to 3.5 Hz

  18. Decimetric type III radio bursts and associated hard X-ray spikes

    Science.gov (United States)

    Dennis, B. R.; Benz, A. O.; Ranieri, M.; Simnett, G. M.

    1984-01-01

    For a relatively weak solar flare on August 6, 1981, at 10:32 UT, a detailed comparison is made between hard X-ray spikes and decimetric type III radio bursts. The hard X-ray observations are made at energies above 30 keV, and the radio data are obtained in the frequency range from 100 to 1000 MHz. The time resolution for all the data sets is approximately 0.1 s or better. The dynamic radio spectrum exhibits many fast drift type III radio bursts with both normal and reverse slope, whereas the X-ray time profile contains many well resolved short spikes with durations less than or equal to 1 s. Some of the X-ray spikes are seen to be associated in time with reverse-slope bursts, indicating either that the electron beams producing the radio burst contain two or three orders of magnitude more fast electrons than has previously been assumed or that the electron beams can induce the acceleration of additional electrons or occur in coincidence with this acceleration. A case is presented in which a normal slope radio burst at approximately 600 MHz occurs in coincidence with the peak of an X-ray spike to within 0.1 s.

  19. Searches for hard X-ray gamma-ray burst afterglows with the BAT on Swift

    International Nuclear Information System (INIS)

    Krimm, Hans A.; Ozawa, Hideki; Weidenspointner, Georg; Barbier, Louis M.; Barthelmy, Scott D.; Gehrels, Neil; Parsons, Ann M.; Tueller, Jack; Eftekharzadeh, Ardeshir; Hullinger, Derek D.; Markwardt, Craig; Fenimore, Edward E.; Palmer, David M.

    2003-01-01

    The Burst Alert Telescope (BAT) on the Swift gamma ray burst mission will continue to observe the fields of all detected gamma-ray bursts for several days after the prompt emission has faded. Utilizing first event-by-event data, then one minute and later five minute survey accumulations, the BAT will be extremely sensitive to the hard X-ray afterglow known to be associated with many bursts. This data will cover the crucial transition of the afterglow from rapid variability to the smoothly decaying power law in time and will extend observations of the tails of individual bursts to longer time scales than have been achievable so far. Since Swift is sensitive to short duration GRBs, we will also be able to determine whether hard X-ray afterglows are associated with short GRBs. The BAT will provide high resolution spectra of burst afterglows, allowing us to study in detail the time evolution of GRB spectra

  20. A hard x-ray prototype production exposure station at NSLS

    International Nuclear Information System (INIS)

    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 ∼ 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

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

    International Nuclear Information System (INIS)

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

    2014-01-01

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

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

    International Nuclear Information System (INIS)

    Rutherford, Michael E.; Chapman, David J.; White, Thomas G.; Drakopoulos, Michael; Rack, Alexander; Eakins, Daniel E.

    2016-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-03-24

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

  4. Exploring the Hard and Soft X-ray Emission of Magnetic Cataclysmic Variables

    Science.gov (United States)

    de Martino, D.; Anzolin, G.; Bonnet-Bidaud, J.-M.; Falanga, M.; Matt, G.; Mouchet, M.; Mukai, K.; Masetti, N.

    2009-05-01

    A non-negligible fraction of galactic hard (>20 keV) X-ray sources were identified as CVs of the magnetic Intermediate Polar type in INTEGRAL, SWIFT and RXTE surveys, that suggests a still hidden but potentially important population of faint hard X-ray sources. Simbol-X has the unique potential to simultaneously characterize their variable and complex soft and hard X-ray emission thus allowing to understand their putative role in galactic populations of X-ray sources.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-04-15

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

  6. Hard x-ray telescope mission

    DEFF Research Database (Denmark)

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

    1996-01-01

    The Hard X-Ray Telescope was selected for study as a possible new intermediate size mission for the early 21st century. Its principal attributes are: (1) multiwavelength observing with a system of focussing telescopes that collectively observe from the UV to over 1 MeV, (2) much higher sensitivity...

  7. SMM hard X-ray observations of the soft gamma-ray repeater 1806-20

    Science.gov (United States)

    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.

  8. SMM hard X-ray observations of the soft gamma-ray repeater 1806-20

    International Nuclear Information System (INIS)

    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. 19 references

  9. Recent applications of hard x-ray photoelectron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Weiland, Conan; Woicik, Joseph C., E-mail: Joseph.Woicik@NIST.gov [National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States); Rumaiz, Abdul K. [National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973 (United States); Pianetta, Piero [SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States)

    2016-05-15

    Recent applications of hard x-ray photoelectron spectroscopy (HAXPES) demonstrate its many capabilities in addition to several of its limitations. Examples are given, including measurement of buried interfaces and materials under in situ or in operando conditions, as well as measurements under x-ray standing-wave and resonant excitation. Physical considerations that differentiate HAXPES from photoemission measurements utilizing soft x-ray and ultraviolet photon sources are also presented.

  10. NuSTAR hard X-ray observations of the Jovian magnetosphere during Juno perijove and apojove intervals

    Science.gov (United States)

    Dunn, W.; Mori, K.; Hailey, C. J.; Branduardi-Raymont, G.; Grefenstette, B.; Jackman, C. M.; Hord, B. J.; Ray, L. C.

    2017-12-01

    The Nuclear Spectroscopic Telescope Array (NuSTAR) is the first focusing hard X-ray telescope operating in the 3-79 keV band with sub-arcminute angular resolution (18" FWHM). For the first time, NuSTAR provides sufficient sensitivity to detect/resolve hard X-ray emission from Jupiter above 10 keV, since the in-situ Ulysses observation failed to detect X-ray emission in the 27-48 keV band [Hurley et al. 1993]. The initial, exploratory NuSTAR observation of Jupiter was performed in February 2015 with 100 ksec exposure. NuSTAR detected hard X-ray emission (E > 10 keV) from the south polar region at a marginally significance of 3 sigma level [Mori et al. 2016, AAS meeting poster]. This hard X-ray emission is likely an extension of the non-thermal bremsstrahlung component detected up to 7 keV by XMM-Newton [Branduardi-Raymont et al. 2007]. The Ulysses non-detection suggests there should be a spectral cutoff between 7 and 27 keV. Most intriguingly, the NuSTAR detection of hard X-ray emission from the south aurora is in contrast to the 2003 XMM-Newton observations where soft X-ray emission below 8 keV was seen from both the north and south poles [Gladstone et al. 2002]. Given the marginal, but tantalizing, hard X-ray detection of the southern Jovian aurora, a series of NuSTAR observations with total exposure of nearly half a million seconds were approved in the NuSTAR GO and DDT program. These NuSTAR observations coincided with one Juno apojove (in June 2017) and three perijoves (in May, July and September 2017), also joining the multi-wavelength campaigns of observing Jupiter coordinating with Chandra and XMM-Newton X-ray telescope (below 10 keV) and HST. We will present NuSTAR imaging, spectral and timing analysis of Jupiter. NuSTAR imaging analysis will map hard X-ray emission in comparison with soft X-ray and UV images. In addition to investigating any distinctions between the soft and hard X-ray morphology of the Jovian aurorae, we will probe whether hard X-ray

  11. Hard X-ray techniques suitable for polymer experiments

    Energy Technology Data Exchange (ETDEWEB)

    Bras, W; Goossens, H; Goderis, B, E-mail: Wim.Bras@esrf.fr [Netherlands Organisation for Scientific Research (NWO) (Netherlands); DUBBLE-ESRF, BP 220, F38043 Grenoble Cedex (France); Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven (Netherlands); Molecular and Nanomaterials, Chemistry Department, Catholic University of Leuven, Celestijnenlaan 200F (Belgium)

    2010-11-15

    Polymers have been studied since 1979 with 8-12 keV synchrotron radiation X-ray scattering methods and the number and sophistication of the experiments have rapidly grown ever since. More recently, new experimental techniques have been developed that use softer or harder X-rays in less conventional ways. This article provides a brief overview of the possibilities of hard X-ray techniques and indicates some areas that might gain from further developments.

  12. Hard X-ray techniques suitable for polymer experiments

    International Nuclear Information System (INIS)

    Bras, W; Goossens, H; Goderis, B

    2010-01-01

    Polymers have been studied since 1979 with 8-12 keV synchrotron radiation X-ray scattering methods and the number and sophistication of the experiments have rapidly grown ever since. More recently, new experimental techniques have been developed that use softer or harder X-rays in less conventional ways. This article provides a brief overview of the possibilities of hard X-ray techniques and indicates some areas that might gain from further developments.

  13. Blazars in Hard X-rays

    Science.gov (United States)

    Ghisellini, Gabriele

    2009-05-01

    Although blazars are thought to emit most of their luminosity in the γ-ray band, there are subclasses of them very prominent in hard X-rays. These are the best candidates to be studied by Simbol-X. They are at the extremes of the blazar sequence, having very small or very high jet powers. The former are the class of TeV emitting BL Lacs, whose synchrotron emission often peaks at tens of keV or more. The latter are the blazars with the most powerful jets, have high black hole masses accreting at high (i.e. close to Eddington) rates. These sources are predicted to have their high energy peak even below the MeV band, and therefore are very promising candidates to be studied with Simbol-X.

  14. Sub-second pulsations simultaneously observed at microwaves and hard X-rays in a solar burst

    International Nuclear Information System (INIS)

    Takakura, T.; Degaonkar, S.S.; Nitta, N.; Ohki, N.

    1982-11-01

    Sub-second time structures have been found in the emissions during solar bursts in mm-waves and, independently, in hard X-rays. However, simultaneous observations of such fast time structure in mm radio and X-ray ranges has not been available so far. Accordingly, coordinated observations of solar bursts in November 1981 with a high time resolution of a few milliseconds were planned. The hard X-rays (30-40 KeV were observed with hard X-ray monitor (HXM) aboard the Hinotori Satellite with a time resolution of 7.81 ms and the radio emissions were observed on the ground with 45ft dish at Itapetinga Radio Observatory with a high time resolution (1 ms) and high sensitivities at 22 GHz and 44 GHz, supplemented by a patrol observation at 7 GHz with time resolution of 100 ms. The pulsations repeated with a period of about 300 ms. The physical implication of the good correlation is not clear at this stage, but it may give a clue to the understanding of the high energy phenomena occuring during the solar flares. (Author) [pt

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

    Science.gov (United States)

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

    2017-07-01

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

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

    Science.gov (United States)

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

    2016-03-01

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

  17. Model independent method to deconvolve hard X-ray spectra

    Energy Technology Data Exchange (ETDEWEB)

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

    1984-07-01

    A general purpose method to deconvolve the energy spectra detected by means of the use of a hard X-ray telescope is described. The procedure does not assume any form of input spectrum and the observed energy loss spectrum is directly deconvolved into the incident photon spectrum, the form of which can be determined independently of physical interpretation of the data. Deconvolution of the hard X-ray spectrum of Her X-1, detected during the HXR 81M experiment, by the method independent method is presented.

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

    Science.gov (United States)

    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.; hide

    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.

  19. Hard X ray lines from neutron stars

    Energy Technology Data Exchange (ETDEWEB)

    Polcaro, V.F.; Bazzano, A.; La Padula, C.; Ubertini, P.

    1982-01-01

    Experimental evidence is presented and evaluated concerning the features of the hard X-ray spectra detected in a number of cosmic X-ray sources which contain a neutron star. The strong emission line at cyclotron resonance detected in the spectrum of Her XI at an energy of 58 keV is evaluated and the implications of this finding are discussed. Also examined is the presence of spectral features in the energy range 20-80 keV found in the spectra of gamma-ray bursts, which have been interpreted as cyclotron resonance from interstellar-gas-accreting neutron stars. The less understood finding of a variable emission line at approximately 70 keV in the spectrum of the Crab Pulsar is considered. It is determined that several features varying with time are present in the spectra of cosmic X-ray sources associated with neutron stars. If these features are due to cyclotron resonance, it is suggested that they provide a direct measurement of neutron star magnetic fields on the order of 10 to the 11th-10 to the 13th Gauss. However, the physical condition of the emitting region and its geometry are still quite obscure.

  20. Analysis of the 1980 November 18 limb flare observed by the hard X-ray imaging spectrometer (HXIS)

    NARCIS (Netherlands)

    Hoyng, P.; Haug, E.; Elwert, G.

    1984-01-01

    X-ray images of the 18 November 1980 limb flare taken by the HXIS instrument aboard SMM were analysed. The hard X-rays originated from three spots on the SW limb of the solar disk with different altitudes and time evolution. The locations of the brightest spots in hard and soft X-rays are compared

  1. Hard x- and gamma-rays from supernova 1987A

    International Nuclear Information System (INIS)

    Kumagai, S.; Shigeyama, T.; Nomoto, K.; Nishmura, J.; Itoh, M.

    1988-01-01

    The x-ray light curve and spectrum from SN 1987A due to Compton degradation of γ-rays from the 56 Co decay are calculated and compared with the Ginga and Kvant observations. If mixing of 56 Co into outer layers has taken place, the x-rays emerge much earlier than in the case without mixing and the resulting hard x-rays are in reasonable agreement with observations

  2. Hard X-ray spectrum of Her X-1

    International Nuclear Information System (INIS)

    Ubertini, P.; Bazzano, A.; La Padula, C.D.; Polcaro, V.F.

    1981-01-01

    The results of a balloon borne hard X-ray observation of Her X-1 is presented. The experiment, released from the base of Hyderabad (India) the 19th April 1980, was a collaboration between the Istituto di Astrofisica Spaziale (Italy) and the TIFR (India). The data obtained are compatible with a thermal emission at low energy with a strong emission line overimposed on the continuum around 50-60 keV

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

    International Nuclear Information System (INIS)

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

    2015-01-01

    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

  4. Studies in useful hard x-ray induced chemistry

    Science.gov (United States)

    Pravica, Michael; Bai, Ligang; Sneed, Daniel; Park, Changyong

    2013-06-01

    The observed rapid decomposition of potassium chlorate (via 2KClO3 + h ν --> 2KCl +3O2) via synchrotron hard x-ray irradiation (>10 keV) has enabled experiments that are developing novel and useful hard x-ray chemistry. We have observed a number of radiation-induced in situ decomposition reactions in various substances which release O2, H2, N2, NH3, and H2O in a diamond anvil cell (DAC) at ambient and high pressures. These novel acatalytic and isothermal reactions represent a highly controllable, penetrating, and focused method to initiate chemistry (including x-ray induced combustion) in sealed and/or isolated chambers which maintain matter under extreme conditions. During our studies, we have typically observed a slowing of decomposition with pressure including phase dependent decomposition of KClO3. Energy dependent studies have observed an apparent resonance near 15 keV at which the decomposition rate is maximized. This may enable use of much lower flux and portable x-ray sources (e.g. x-ray tubes) in larger scale experiments. These developments support novel means to load DACs and control chemical reactions providing novel routes of synthesis of novel materials under extreme conditions.

  5. The 105-Month Swift-BAT All-Sky Hard X-Ray Survey

    Science.gov (United States)

    Oh, Kyuseok; Koss, Michael; Markwardt, Craig B.; Schawinski, Kevin; Baumgartner, Wayne H.; Barthelmy, Scott D.; Cenko, S. Bradley; Gehrels, Neil; Mushotzky, Richard; Petulante, Abigail; hide

    2018-01-01

    We present a catalog of hard X-ray sources detected in the first 105 months of observations with the Burst Alert Telescope (BAT) coded-mask imager on board the Swift observatory. The 105-month Swift-BAT survey is a uniform hard X-ray all-sky survey with a sensitivity of 8.40 x 10(exp -12) erg s(exp -1) cm(exp -2) over 90% of the sky and 7.24 x 10(exp -12) erg s(exp -1) cm(exp -2) over 50% of the sky in the 14-195 keV band. The Swift-BAT 105-month catalog provides 1632 (422 new detections) hard X-ray sources in the 14-195 keV band above the 4.8 sigma significance level. Adding to the previously known hard X-ray sources, 34% (144/422) of the new detections are identified as Seyfert active galactic nuclei (AGNs) in nearby galaxies (z < 0.2). The majority of the remaining identified sources are X-ray binaries (7%, 31) and blazars/BL Lac objects (10%, 43). As part of this new edition of the Swift-BAT catalog, we release eight-channel spectra and monthly sampled light curves for each object in the online journal and at the Swift-BAT 105-month website.

  6. Hard X-ray balloon observations of compact galactic and extragalactic X-ray sources

    International Nuclear Information System (INIS)

    Staubert, R.; Kendziorra, E.; Pietsch, W.; Proctor, R.J.; Reppin, C.; Steinle, H.; Truemper, J.; Voges, W.

    1981-01-01

    A balloon program in hard X-ray astronomy (20-200 keV) is jointly pursued by the Astronomisches Institut der Universitaet Tuebingen (AIT) and the Max Planck-Institut fuer Extraterrestrische Physik in Garching (MPE). Since 1973 nine succussful balloon flights have been performed from Texas and Australia. Here results on Centaurus A and on several galactic binary X-ray sources are summarized. In particular the high energy photon spectrum of Hercules X-1 and the evidence for the cyclotron line feature which was discovered by us in 1976 is reviewed. (orig.)

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

    Directory of Open Access Journals (Sweden)

    M. Beilicke

    2014-12-01

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

  8. Hard X-ray intensity reduction during lower hybrid current drive experiments

    International Nuclear Information System (INIS)

    Mlynar, J.; Stoeckel, J.; Magula, P.

    1993-01-01

    A strong hard X-ray intensity reduction during a standard LHCD at the CASTOR tokamak was studied. From discussion it followed that the magnetic fluctuations level decrease is likely to be responsible for this effect beside the loop voltage decrease. To verify this idea, the connection between the magnetic fluctuation level and the hard X-ray intensity was studied in a nonstandard LHCD regime with a zero loop voltage reduction. These measurements strongly supported the concept that magnetic fluctuations level substantially influences the runaway electrons cross-field transport. Though, more data and a good code for modelling the anomalous transport and hard X-rays production would be of high value. Similar measurements especially for higher RF power should be carried out soon. Besides, the reduction of hard X-rays was observed in the experiments with edge plasma polarization lately; therefore, the magnetic fluctuations level in these experiments should be studied soon. (author) 6 figs., 6 refs

  9. Real-time algorithms for JET hard X-ray and gamma-ray profile monitor

    International Nuclear Information System (INIS)

    Fernandes, A.; Pereira, R.C.; Valcárcel, D.F.; Alves, D.; Carvalho, B.B.; Sousa, J.; Kiptily, V.; Correia, C.M.B.A.; Gonçalves, B.

    2014-01-01

    Highlights: • Real-time tools and mechanisms are required for data handling and machine control. • A new DAQ system, ATCA based, with embedded FPGAs, was installed at JET. • Different real-time algorithms were developed for FPGAs and MARTe application. • MARTe provides the interface to CODAS and to the JET real-time network. • The new DAQ system is capable to process and deliver data in real-time. - Abstract: The steady state operation with high energy content foreseen for future generation of fusion devices will necessarily demand dedicated real-time tools and mechanisms for data handling and machine control. Consequently, the real-time systems for those devices should be carefully selected and their capabilities previously established. The Joint European Torus (JET) is undertaking an enhancement program, which includes tests of relevant real-time tools for the International Thermonuclear Experimental Reactor (ITER), a key experiment for future fusion devices. In these enhancements a new Data AcQuisition (DAQ) system is included, with real-time processing capabilities, for the JET hard X-ray and gamma-ray profile monitor. The DAQ system is composed of dedicated digitizer modules with embedded Field Programmable Gate Array (FPGA) devices. The interface between the DAQ system, the JET control and data acquisition system and the JET real-time data network is provided by the Multithreaded Application Real-Time executor (MARTe). This paper describes the real-time algorithms, developed for both digitizers’ FPGAs and MARTe application, capable of meeting the DAQ real-time requirements. The new DAQ system, including the embedded real-time features, was commissioned during the 2012 experiments. Results achieved with these real-time algorithms during experiments are presented

  10. Real-time algorithms for JET hard X-ray and gamma-ray profile monitor

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, A., E-mail: anaf@ipfn.ist.utl.pt [Associação EURATOM/IST, Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade Técnica de Lisboa, 1049-001 Lisboa (Portugal); Pereira, R.C.; Valcárcel, D.F.; Alves, D.; Carvalho, B.B.; Sousa, J. [Associação EURATOM/IST, Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade Técnica de Lisboa, 1049-001 Lisboa (Portugal); Kiptily, V. [EURATOM/CCFE Fusion Association, Culham Centre for Fusion Energy, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Correia, C.M.B.A. [Centro de Instrumentação, Dept. de Física, Universidade de Coimbra, 3004-516 Coimbra (Portugal); Gonçalves, B. [Associação EURATOM/IST, Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade Técnica de Lisboa, 1049-001 Lisboa (Portugal)

    2014-03-15

    Highlights: • Real-time tools and mechanisms are required for data handling and machine control. • A new DAQ system, ATCA based, with embedded FPGAs, was installed at JET. • Different real-time algorithms were developed for FPGAs and MARTe application. • MARTe provides the interface to CODAS and to the JET real-time network. • The new DAQ system is capable to process and deliver data in real-time. - Abstract: The steady state operation with high energy content foreseen for future generation of fusion devices will necessarily demand dedicated real-time tools and mechanisms for data handling and machine control. Consequently, the real-time systems for those devices should be carefully selected and their capabilities previously established. The Joint European Torus (JET) is undertaking an enhancement program, which includes tests of relevant real-time tools for the International Thermonuclear Experimental Reactor (ITER), a key experiment for future fusion devices. In these enhancements a new Data AcQuisition (DAQ) system is included, with real-time processing capabilities, for the JET hard X-ray and gamma-ray profile monitor. The DAQ system is composed of dedicated digitizer modules with embedded Field Programmable Gate Array (FPGA) devices. The interface between the DAQ system, the JET control and data acquisition system and the JET real-time data network is provided by the Multithreaded Application Real-Time executor (MARTe). This paper describes the real-time algorithms, developed for both digitizers’ FPGAs and MARTe application, capable of meeting the DAQ real-time requirements. The new DAQ system, including the embedded real-time features, was commissioned during the 2012 experiments. Results achieved with these real-time algorithms during experiments are presented.

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

    Indian Academy of Sciences (India)

    explosive destruction of micrograins is accompanied by X-ray radiation (during hydrody- ... makes it possible to produce lasing in hard X-rays due to the effects of multiple scattering ... portant, information on the X-ray random media, including some indirect diagnostics. In ... stages of ionization in the total flux of particles.

  12. Bulk sensitive hard x-ray photoemission electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-11-15

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

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

    International Nuclear Information System (INIS)

    Reyes-Herrera, Juan

    2016-01-01

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

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

    Science.gov (United States)

    Reyes-Herrera, Juan

    2016-10-01

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

  15. Recurrent pulse trains in the solar hard X-ray flare of 1980 June 7

    International Nuclear Information System (INIS)

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

    1983-01-01

    This study presents a detailed examination of the solar hard X-ray and γ-ray flare of 1980 June 7 as seen by the Hard X-Ray Burst Spectrometer on SMM. The hard X-ray profile is most unusual in that it is characterized by an initial pulse train of seven intense hard X-ray spikes. However, the event is unique among the 6300 events observed by HXRBS in that the temporal signature of this pulse train recurs twice during the flare. Such signatures of temporal stability in impulsive solar flares have not been observed before. Examinations of the hard X-ray data in conjunction with radio and γ-ray observations show that the 28--480 keV X-ray emission is simultaneous with the 17 GHz microwave fluxes within 128 ms and that the 3.5--6.5 MeV prompt γ-ray line emission is coincident with secondary maxima of the microwave and X-ray fluxes. Studies of the temporal and spectral properties of the pulses indicate that the pulses are not produced by purely reversible processes, and that if the source is oscillatory, it is not a high quality oscillator. Although the absence of spatially resolved hard X-ray observations leaves other possibilities open, a parameterization of the event as a set of seven sequentially firing loops is presented that offers many satisfying explanations of the observations

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

    DEFF Research Database (Denmark)

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

    1995-01-01

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

  17. Development and application of cryogenic radiometry with hard X-rays

    International Nuclear Information System (INIS)

    Gerlach, Martin

    2008-01-01

    To establish cryogenic radiometry with hard X-ray radiation for photon energies of up to 60 keV, a novel type of cavity absorber had to be developed for the cryogenic radiometer SYRES I, which is deployed by the Physikalisch-Technische Bundesanstalt (PTB) as primary standard detector at the electron storage ring BESSY II. This new type of cavity absorber allows for the complete absorption of hard X-ray radiation in combination with an appropriate sensitivity and an adequate time constant for the measurement of synchrotron radiation at BESSY II. As the process of fabrication of different types of absorbers is very time-consuming, the interaction of hard X-ray radiation with different absorber materials and geometries was studied intensively by using the Monte Carlo simulation code Geant4. The accuracy of the simulations was verified comparing them to scattering experiments performed at a wavelength shifter beamline at BESSY II with a calibrated energy dispersive detector. It was shown that Geant4 describes the photo-effect, including fluorescence as well as Compton- and Rayleigh scattering, with high accuracy. The simulations and experiments resulted in a cavity absorber with a gold base 550 μm in thickness and a cylindrical shell made of copper 90 μm in thickness to reduce losses caused by fluorescence and scattered radiation. Monochromatized synchrotron radiation of high spectral purity was then used to calibrate semiconductor photodiodes, which can be used as compact and inexpensive secondary standard detectors, against a cryogenic radiometer, covering the entire photon energy range of three beamlines from 50 eV to 60 keV with relative uncertainties of less than 0.5 %. Furthermore the spatial homogeneity of the spectral responsivity, the transmittance and the linearity of the photodiodes was investigated. Through a direct comparison of the free-air ionization chamber PK100, a primary detector standard of PTB used in dosimetry, and the cryogenic radiometer SYRES

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

    Energy Technology Data Exchange (ETDEWEB)

    Krimm, H. A.; Holland, S. T.; Corbet, R. H. D.; Pearlman, A. B.; Baumgartner, W. H.; Cummings, J. R. [Center for Research and Exploration in Space Science and Technology (CRESST) and NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Romano, P. [INAF, Istituto di Astrofisica Spaziale e Fisica Cosmica, Via U. La Malfa 153, I-90146 Palermo (Italy); Kennea, J. A. [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States); Bloom, J. S. [Department of Astronomy, University of California, Berkeley, Berkeley, CA 94720-3411 (United States); Barthelmy, S. D.; Gehrels, N.; Lien, A. Y.; Markwardt, C. B.; Ukwatta, T. N. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Palmer, D. M. [Los Alamos National Laboratory, B244, Los Alamos, NM 87545 (United States); Sakamoto, T. [Department of Physics and Mathematics, College of Science and Engineering, Aoyama Gakuin University, 5-10-1 Fuchinobe, Chuo-ku, Sagamihara-shi, Kanagawa 252-5258 (Japan); Stamatikos, M. [Department of Physics and Center for Cosmology and Astro-Particle Physics, Ohio State University, Columbus, OH 43210 (United States)

    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.

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

    Science.gov (United States)

    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.; hide

    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.

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

    Science.gov (United States)

    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.; hide

    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.

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

    International Nuclear Information System (INIS)

    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.

    2013-01-01

    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

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

    DEFF Research Database (Denmark)

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

    2015-01-01

    The low-mass X-ray binary Cen X-4 is the brightest and closest (<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 unkno...... 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....

  3. Hard X-ray Microscopy with Elemental, Chemical and Structural Contrast

    International Nuclear Information System (INIS)

    Schroer, C.G.; Boye, P.; Feldkamp, J.P.

    2010-01-01

    We review hard X-ray microscopy techniques with a focus on scanning microscopy with synchrotron radiation. Its strength compared to other microscopies is the large penetration depth of hard x rays in matter that allows one to investigate the interior of an object without destructive sample preparation. In combination with tomography, local information from inside of a specimen can be obtained, even from inside special non-ambient sample environments. Different X-ray analytical techniques can be used to produce contrast, such as X-ray absorption, fluorescence, and diffraction, to yield chemical, elemental, and structural information about the sample, respectively. This makes X-ray microscopy attractive to many fields of science, ranging from physics and chemistry to materials, geo-, and environmental science, biomedicine, and nanotechnology. Our scanning microscope based on nanofocusing refractive X-ray lenses has a routine spatial resolution of about 100 nm and supports the contrast mechanisms mentioned above. In combination with coherent X-ray diffraction imaging, the spatial resolution can be improved to the 10 nm range. The current state-of-the-art of this technique is illustrated by several examples, and future prospects of the technique are given. (author)

  4. Monitoring the Galactic - Search for Hard X-Ray Transients

    Science.gov (United States)

    Marshall, Francis

    Hard X-ray transients with fluxs from ~1 to ~30 mCrab are a common feature of the galactic plane with apparent concentrations in specific regions of the plane. Concentrations in the Scutum and Carina fields probably indicate an enhancement of Be X-ray binaries along the tangent direction of two spiral arms. The frequency of outbursts suggest that at any one time 1 or 2 transients are active in the Scutum field alone. We propose weekly scans of the galactic plane to understand this population of sources. The scans will also monitor about 50 already known sources with better spectral information than available with the ASM.

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

    International Nuclear Information System (INIS)

    Correa, C

    2004-01-01

    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

  6. Fast solar hard X-ray bursts and large scale coronal structures

    International Nuclear Information System (INIS)

    Simnett, G.M.

    1982-01-01

    The conditions at the Sun at the times corresponding to a selected set 22 fast impulsive hard X-ray bursts reported by Crannell et al. are examined. It is suggested that one of the bursts must arise from a precipitating beam of subrelativistic electrons; the source of the electrons is postulated to be in a region very remote from the X-ray site on the basis of type III and other radio data. The connection is via a coronal magnetic loop extending to approx.3 R/sub sun/ above the photosphere. The energy in the electron beam is estimated at 3 x 10 27 ergs. Intense soft X-ray and/or microwave radio storms at times corresponding to many of the impulsive X-ray bursts lead the conclusion that 14, and possibly 18, of the 22 bursts could have the same interpretation. The energy in such an electron beam could be important when considering the trigger phase of some flares

  7. A model independent method to deconvolve hard X-ray spectra

    International Nuclear Information System (INIS)

    Polcaro, V.F.; Bazzano, A.; Ubertini, P.; La Padula, C.

    1984-01-01

    A general purpose method to deconvolve the energy spectra detected by means of the use of a hard X-ray telescope is described. The procedure does not assume any form of input spectrum and the observed energy loss spectrum is directly deconvolved into the incident photon spectrum, the form of which can be determined independently of physical interpretation of the data. Deconvolution of the hard X-ray spectrum of Her X-1, detected during the HXR 81M experiment, by the method independent method is presented. (orig.)

  8. Spatial and temporal structures of impulsive bursts from solar flares observed in UV and hard X-rays

    Science.gov (United States)

    Cheng, C.-C.; Tandberg-Hanssen, E.; Bruner, E. C.; Orwig, L.; Frost, K. J.; Kenny, P. J.; Woodgate, B. E.; Shine, R. A.

    1981-01-01

    New observations are presented of impulsive UV and hard X-rays bursts in two solar flares obtained with instruments on Solar Maximum Mission. The UV bursts were observed in the Si IV and O IV emission lines, whose intensity ratio is density-sensitive. By comparing the spatially resolved Si IV/O IV observations with the corresponding hard X-ray observations, it is possible to study their spatial and temporal relationships. For one flare, the individual component spikes in the multiply peaked hard X-ray burst can be identified with different discrete Si IV/O IV flaring kernels of size 4 arcsec x 4 arcsec or smaller, which brighten up sequentially in time. For the other, many Si IV/O kernels, widely distributed over a large area, show impulsive bursts at the same time, which correlate with the main peak of the impulsive hard X-ray burst. The density of the flaring Si IV/O IV kernels is in the range from 5 x 10 to the 12th-13th/cu cm.

  9. The 105-Month Swift-BAT All-sky Hard X-Ray Survey

    Science.gov (United States)

    Oh, Kyuseok; Koss, Michael; Markwardt, Craig B.; Schawinski, Kevin; Baumgartner, Wayne H.; Barthelmy, Scott D.; Cenko, S. Bradley; Gehrels, Neil; Mushotzky, Richard; Petulante, Abigail; Ricci, Claudio; Lien, Amy; Trakhtenbrot, Benny

    2018-03-01

    We present a catalog of hard X-ray sources detected in the first 105 months of observations with the Burst Alert Telescope (BAT) coded-mask imager on board the Swift observatory. The 105-month Swift-BAT survey is a uniform hard X-ray all-sky survey with a sensitivity of 8.40× {10}-12 {erg} {{{s}}}-1 {cm}}-2 over 90% of the sky and 7.24× {10}-12 {erg} {{{s}}}-1 {cm}}-2 over 50% of the sky in the 14–195 keV band. The Swift-BAT 105-month catalog provides 1632 (422 new detections) hard X-ray sources in the 14–195 keV band above the 4.8σ significance level. Adding to the previously known hard X-ray sources, 34% (144/422) of the new detections are identified as Seyfert active galactic nuclei (AGNs) in nearby galaxies (zBAT catalog, we release eight-channel spectra and monthly sampled light curves for each object in the online journal and at the Swift-BAT 105-month website.

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

    DEFF Research Database (Denmark)

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

    2016-01-01

    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...

  11. Hard X-ray Flux from Low-Mass Stars in the Cygnus OB2 Association

    Science.gov (United States)

    Caramazza, M.; Drake, J. J.; Micela, G.; Flaccomio, E.

    2009-05-01

    We investigate the X-ray emission in the 20-40 keV band expected from the flaring low-mass stellar population in Cygnus OB2 assuming that the observed soft X-ray emission is due to a superposition of flares and that the ratio of hard X-ray to soft X-ray emission is described by a scaling found for solar flares by Isola and co-workers. We estimate a low-mass stellar hard X-ray flux in the 20-40 keV band in the range ~7×1031-7×1033 erg/s and speculate the limit of this values. Hard X-ray emission could lie at a level not much below the current observed flux upper limits for Cygnus OB2. Simbol-X, with its broad energy band (10-100 keV) and its sensitivity should be able to detect this emission and would provide insights into the hard X-ray production of flares on pre-main sequence stars.

  12. Nustar Detection of Hard X-Ray Phase Lags from the Accreting Pulsar GS 0834-430

    DEFF Research Database (Denmark)

    Miyasaka, Hiromasa; Bachetti, Matteo; Harrison, Fiona A.

    2013-01-01

    The Nuclear Spectroscopic Telescope Array hard X-ray telescope observed the transient Be/X-ray binary GS 0834-430 during its 2012 outburst-the first active state of this system observed in the past 19 yr. We performed timing and spectral analysis and measured the X-ray spectrum between 3-79 keV w...

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

    International Nuclear Information System (INIS)

    Graetz, M.

    1998-11-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Graetz, M

    1998-11-01

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

  15. Hard-x-ray phase-difference microscopy with a low-brilliance laboratory x-ray source

    International Nuclear Information System (INIS)

    Kuwabara, Hiroaki; Yashiro, Wataru; Harasse, Sebastien; Momose, Atsushi; Mizutani, Haruo

    2011-01-01

    We have developed a hard-X-ray phase-imaging microscopy method using a low-brilliance X-ray source. The microscope consists of a sample, a Fresnel zone plate, a transmission grating, and a source grating creating an array of mutually incoherent X-ray sources. The microscope generates an image exhibiting twin features of the sample with opposite signs separated by a distance, which is processed to generate a phase image. The method is quantitative even for non-weak-phase objects that are difficult to be quantitatively examined by the widely used Zernike phase-contrast microscopy, and it has potentially broad applications in the material and biological science fields. (author)

  16. Development of thermally formed glass optics for astronomical hard X-ray telescopes

    DEFF Research Database (Denmark)

    Craig, W.W.; Hailey, C.J.; Jimenez-Garate, M.

    2000-01-01

    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...

  17. Accretion flow diagnostics with X-ray spectral timing: the hard state of SWIFT J1753.5-0127

    NARCIS (Netherlands)

    Cassatella, P.; Uttley, P.; Maccarone, T.

    2012-01-01

    Recent XMM-Newton studies of X-ray variability in the hard states of black hole X-ray binaries (BHXRBs) indicate that the variability is generated in the ‘standard’ optically thick accretion disc that is responsible for the multi-colour blackbody emission. The variability originates in the disc as

  18. Imaging escape gated MPWC for hard X-ray astronomy

    Energy Technology Data Exchange (ETDEWEB)

    Ubertini, P.; Bazzano, A.; Boccaccini, L.; La Padula, C.; Mastropietro, M.; Patriarca, R.; Polcaro, V.F.; Barbareschi, L.; Perotti, F.; Villa, G.

    1983-11-15

    A scientific forward step in the hard X-ray and soft gamma-ray astronomy will only be possible with the use of a new generation of space borne instruments. Their main characteristics have to be the two-dimensional imaging capability over a large collecting area and the fine spectral resolution in order to discriminate between the weak signal coming from cosmic sources to be detected and the strong background induced by cosmic rays, in the space environment, on the detector. To reach this goal we have developed a new hard X-ray position sensitive proportional counter operating with the escape gate technique in the range 15-150 keV, to be used together with a pseudo-random coded mask in order to obtain sky images. The detector is a high pressure (5 bar) xenon-argon-isobutane filled chamber with a spatial resolution of 30x2 mm and a spectral resolution of 5% at 60 keV on the sensitive area of 3000 cm/sup 2/.

  19. Observation of hard X-rays line emission from Her X-1

    Energy Technology Data Exchange (ETDEWEB)

    Polcaro, V.F.; Bazzano, A.; la Padula, C.; Ubertini, P.; Vialetto, G.; Manchanda, R.K.; Damle, S.V.

    1982-04-01

    We present the results of a hard X-ray measurement of the binary source Her X-1, carried out with a balloon borne X-ray telescope consisting of two Multiwire Proportional Counters, having 900 cm/sup 2/ sensitive area each and spectral resolution of 15% and 24% FWHM respectively at 60 keV. The source was observed during the 'Mid-on' state. Our data confirm the previously reported high energy emission line overimposed on the low energy thermal spectrum.

  20. Design of the data management system for hard X-ray modulation telescope based on real-time Linux

    International Nuclear Information System (INIS)

    Jia Tao; Zhang Zhi

    2004-01-01

    Hard X-ray Modulation Telescope is an electronic subsystem, the data management system for capturing the data of the telescope, then managing and transferring them. The data management system also deals with the communication with the satellite. Because of these functions, it needs highly steady quality and good real-time performance. This paper describes the design of the system. (authors)

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

    International Nuclear Information System (INIS)

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

    2016-01-01

    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.

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

    DEFF Research Database (Denmark)

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

    2005-01-01

    We present the study of one year of INTEGRAL data on the neutron star low mass X-ray binary GX 5-1. Thanks to the excellent angular resolution and sensitivity of INTEGRAL, we are able to obtain a high quality spectrum of GX 5-1 from similar to 5keV to similar to 100 keV, for the first time without...... contamination from the nearby black hole candidate GRS 1758-258 above 20 keV. During our observations, GX 5-1 was mostly found in the horizontal and normal branch of its hardness intensity diagram. A clear hard X-ray emission is observed above similar to 30 keV which exceeds the exponential cut-off spectrum...... expected from lower energies. This spectral flattening may have the same origin of the hard components observed in other Z sources as it shares the property of being characteristic to the horizontal branch. The hard excess is explained by introducing Compton up-scattering of soft photons from the neutron...

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

    International Nuclear Information System (INIS)

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

    2007-01-01

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

  4. Comparison of hard X-ray spectra obtained by spectrometers on Hinotori and SMM and detection of 'superhot' component

    Science.gov (United States)

    Nitta, Nariaki

    1988-01-01

    Hard X-ray spectra in solar flares obtained by the broadband spectrometers aboard Hinotori and SMM are compared. Within the uncertainty brought about by assuming the typical energy of the background X-rays, spectra by the Hinotori spectrometer are usually consistent with those by the SMM spectrometer for flares in 1981. On the contrary, flares in 1982 persistently show 20-50-percent higher flux by Hinotori than by SMM. If this discrepancy is entirely attributable to errors in the calibration of energy ranges, the errors would be about 10 percent. Despite such a discrepancy in absolute flux, in the the decay phase of one flare, spectra revealed a hard X-ray component (probably a 'superhot' component) that could be explained neither by emission from a plasma at about 2 x 10 to the 7th K nor by a nonthermal power-law component. Imaging observations during this period show hard X-ray emission nearly cospatial with soft X-ray emission, in contrast with earlier times at which hard and soft X-rays come from different places.

  5. The Elusive Soft Emission from Hard X-ray Symbiotic System RT Cru

    Science.gov (United States)

    Karovska, Margarita

    2014-09-01

    RT Cru is a fascinating member of a new class of hard X-ray emitting symbiotic binaries showing X-ray emission extending to over 50keV. While its hard X-ray emission has been studied in detail, the soft component of the spectrum, including flares, remains elusive, since previous observations have focused on the high-energy regime. We propose Chandra HRC-S/LETG observations to determine the spatial, spectral, and temporal characteristics of the source of the soft X-ray emission with a goal to establish the origin of the soft component, and determine whether and how it is tied to the hard component. Determining the origin of the soft emission is a crucial piece of the puzzle to understanding the geometry, energetics, and the environment of WD accretion in this class of symbiotic systems.

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

    Czech Academy of Sciences Publication Activity Database

    Oberta, Peter; Mokso, R.

    2013-01-01

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

  7. X-ray magnetic circular dichroism and hard X-ray photoelectron spectroscopy of tetragonal Mn72Ge28 epitaxial thin film

    Science.gov (United States)

    Kim, Jinhyeok; Mizuguchi, Masaki; Inami, Nobuhito; Ueno, Tetsuro; Ueda, Shigenori; Takanashi, Koki

    2018-04-01

    An epitaxially grown Mn72Ge28 film with a tetragonal crystal structure was fabricated. It was clarified that the film had a perpendicular magnetization and a high perpendicular magnetic anisotropy energy of 14.3 Merg/cm3. The electronic structure was investigated by X-ray magnetic circular dichroism and hard X-ray photoelectron spectroscopy. The obtained X-ray magnetic circular dichroism spectrum revealed that the Mn orbital magnetic moment governed the magnetocrystalline anisotropy of the Mn72Ge28 film. A doublet structure was observed for the Mn 2p3/2 peak of hard X-ray photoelectron spectrum, indicating the spin exchange interaction between the 2p core-hole and 3d valence electrons.

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

    International Nuclear Information System (INIS)

    Lin, R.P.; Schwartz, R.A.; NASA, Goddard Space Flight Center, Greenbelt, MD)

    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. 39 references

  9. Optimising hard X-ray generation from laser-produced plasmas

    International Nuclear Information System (INIS)

    Lindheimer, C.

    1995-04-01

    The aim of this work is to increase the X-ray yield for a laser produced plasma by optimising the focusing conditions and temporal shape of the laser pulses. The focusing conditions are improved by introducing a control system that secures the laser target surface to exact focus within a range of a few micrometers, allowing continuously high laser intensity for plasma generation. The temporal shape of the laser pulses is changed by introducing a saturable absorber in the laser beam. The laser produces a substantial pre-pulse that heats and expands the target material prior to main pulse arrival. The saturable absorber can increase the main pulse/pre-pulse ratio of the laser pulse up to four orders of magnitude and consequently reduce expansion of the target material before the main pulse. The belief is that an increase in target density at the time of main pulse arrival will change the energy distribution of the X-rays, towards a more efficient X-ray production in the hard X-ray region. This report and the work connected to it, includes the preliminary measurements and results for these improvements. 17 refs

  10. Development and characterization of a laser-based hard x-ray source

    International Nuclear Information System (INIS)

    Tillman, C.

    1996-11-01

    A laser-produced plasma was generated by focusing 100 fs laser pulses, with an energy of 150 mJ, onto metal targets. The laser intensity was expected to reach 10 17 W/cm -2 . Radiation was emitted from the created plasma, with photon energies up to the MeV region. The laser-based X-ray source was optimized, with the purpose of making it a realistic source of hard X-rays (>10 keV). Dedicated equipment was developed for efficient generation and utilization of the hard X-rays. The X-ray source was characterized with respect to its spatial extent and the X-ray yield. Measurements were made of the spectral distribution, by the use of single-photon-counting detectors in different geometries, crystal spectrometers and dose measurements in combination with absorption filters. Ablation of the target material in the laser produced plasma was investigated. Imaging applications have been demonstrated, including ultrafast (picosecond) X-ray imaging, magnification imaging of up to x80, differential imaging in the spectral domain, and imaging of various biological and technical objects. The biological response of ultra-intense X-ray pulses was assessed in cell-culture exposures. The results indicate that the biological response from ultra-intense X-ray exposures is similar to the response with conventional X-ray tubes. 82 refs., 14 figs

  11. Development and characterization of a laser-based hard x-ray source

    Energy Technology Data Exchange (ETDEWEB)

    Tillman, C.

    1996-11-01

    A laser-produced plasma was generated by focusing 100 fs laser pulses, with an energy of 150 mJ, onto metal targets. The laser intensity was expected to reach 10{sup 17} W/cm{sup -2}. Radiation was emitted from the created plasma, with photon energies up to the MeV region. The laser-based X-ray source was optimized, with the purpose of making it a realistic source of hard X-rays (>10 keV). Dedicated equipment was developed for efficient generation and utilization of the hard X-rays. The X-ray source was characterized with respect to its spatial extent and the X-ray yield. Measurements were made of the spectral distribution, by the use of single-photon-counting detectors in different geometries, crystal spectrometers and dose measurements in combination with absorption filters. Ablation of the target material in the laser produced plasma was investigated. Imaging applications have been demonstrated, including ultrafast (picosecond) X-ray imaging, magnification imaging of up to x80, differential imaging in the spectral domain, and imaging of various biological and technical objects. The biological response of ultra-intense X-ray pulses was assessed in cell-culture exposures. The results indicate that the biological response from ultra-intense X-ray exposures is similar to the response with conventional X-ray tubes. 82 refs., 14 figs.

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

    Energy Technology Data Exchange (ETDEWEB)

    Pareschi, G.; Pasqualini, G. [Ferrara, Univ. (Italy). Dipt. di Fisica; Frontera, F. [CNR, Bologna (Italy). Istituto di TESRE]|[Ferrara, Univ. (Italy). Dipt. di Fisica

    1997-09-01

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

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

    International Nuclear Information System (INIS)

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

    1997-01-01

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

  14. Hard X-ray-induced optical luminescence via biomolecule-directed metal clusters†

    Science.gov (United States)

    Pratx, Guillem; Sun, Conroy; Sakamoto, Masanori; Ahmad, Moiz; Volotskova, Olga; Ong, Qunxiang; Teranishi, Toshiharu; Harada, Yoshie

    2014-01-01

    Here, we demonstrate that biomolecule-directed metal clusters are applicable in the study of hard X-ray excited optical luminescence, promising a new direction in the development of novel X-ray-activated imaging probes. PMID:24463467

  15. Application of thermoluminescence dosimeter on the measurement of hard X-ray pulse energy spectrum

    International Nuclear Information System (INIS)

    Song Zhaohui; Wang Baohui; Wang Kuilu; Hei Dongwei; Sun Fengrong; Li Gang

    2003-01-01

    This paper introduces the application of thermoluminescence dosimeter (TLD) which composed by TLD-3500 reader and GR-100 M chips on the measurement of hard X-ray pulse energy spectrum. The idea using Filter Fluorescence Method (FFM) and TLD to measure hard X-ray pulse energy spectrum (from 10 keV to 100 keV) is discussed in details. Considering all the factors of the measuring surrounding, the measurement system of hard X-ray pulse has been devised. The calibration technique of absolute energy response of TLD is established. This method has been applied successfully on the radiation parameters measurement of the huge pulse radiation device-high-power pulser I. Hard X-ray pulse energy spectrum data of the pulser are acquired

  16. Weak Hard X-Ray Emission from Two Broad Absorption Line Quasars Observed with NuStar: Compton-Thick Absorption or Intrinsic X-Ray Weakness?

    Science.gov (United States)

    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..; hide

    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%.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-08-01

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

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

    DEFF Research Database (Denmark)

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

    2013-01-01

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

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

    DEFF Research Database (Denmark)

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

    2016-01-01

    We present the results from sensitive, multi-epoch NuSTAR observations of the late-type star-forming galaxy M83 (d = 4.6 Mpc). This is the first investigation to spatially resolve the hard (E > 10 keV) X-ray emission of this galaxy. The nuclear region and similar to 20 off-nuclear point sources......, including a previously discovered ultraluminous X-ray source, are detected in our NuSTAR observations. The X-ray hardnesses and luminosities of the majority of the point sources are consistent with hard X-ray sources resolved in the starburst galaxy NGC 253. We infer that the hard X-ray emission is most...

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

    Science.gov (United States)

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

    1985-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Taito Osaka

    2017-11-01

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

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

    DEFF Research Database (Denmark)

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

    2000-01-01

    Future astronomical X-ray telescopes, including the balloon-borne High-Energy Focusing Telescope (HEFT) and the Constellation-X Hard X-ray Telescope (Con-X HXT) plan to incorporate depth-graded multilayer coatings in order to extend sensitivity into the hard X-ray (10 less than or similar to E less......-graded W/Si multilayers optimized for broadband performance up to 69.5 keV (WK-edge). These designs are ideal for both the HEFT and Con-X HXT applications. We compare the measurements to model calculations to demonstrate that the reflectivity can be well described by the intended power law distribution...

  3. An imaging escape gated MPWC for hard X-ray astronomy

    International Nuclear Information System (INIS)

    Ubertini, P.; Bazzano, A.; Boccaccini, L.; La Padula, C.; Mastropietro, M.; Patriarca, R.; Polcaro, V.F.; Barbareschi, L.; Perotti, F.; Villa, G.; Butler, R.C.; Di Cocco, G.; Spada, G.; Charalambous, P.; Dean, A.J.; Stephen, J.B.

    1983-01-01

    A scientific forward step in the hard X-ray and soft gamma-ray astronomy will only be possible with the use of a new generation of space borne instruments. Their main characteristics have to be the two-dimensional imaging capability over a large collecting area and the fine spectral resolution in order to discriminate between the weak signal coming from cosmic sources to be detected and the strong background induced by cosmic rays, in the space environment, on the detector. To reach this goal we have developed a new hard X-ray position sensitive proportional counter operating with the escape gate technique in the range 15-150 keV, to be used together with a pseudo-random coded mask in order to obtain sky images. The detector is a high pressure (5 bar) xenon-argon-isobutane filled chamber with a spatial resolution of 30x2 mm and a spectral resolution of 5% at 60 keV on the sensitive area of 3000 cm 2 . (orig.)

  4. Crab Nebula Variations in Hard X-rays

    Science.gov (United States)

    Wilson-Hodge, Colleen A.

    2012-01-01

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

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

    Science.gov (United States)

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

    2018-01-01

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

  6. THE 22 MONTH SWIFT-BAT ALL-SKY HARD X-RAY SURVEY

    International Nuclear Information System (INIS)

    Tueller, J.; Baumgartner, W. H.; Markwardt, C. B.; Skinner, G. K.; Mushotzky, R. F.; Barthelmy, S.; Cummings, J.; Gehrels, N.; Holland, S.; Ajello, M.; Beardmore, A.; Evans, P.; Godet, O.; Brandt, W. N.; Burrows, D.; Grupe, D.; Chincarini, G.; Campana, S.; Cusumano, G.; Fenimore, E.

    2010-01-01

    We present the catalog of sources detected in the first 22 months of data from the hard X-ray survey (14-195 keV) conducted with the Burst Alert Telescope (BAT) coded mask imager on the Swift satellite. The catalog contains 461 sources detected above the 4.8σ level with BAT. High angular resolution X-ray data for every source from Swift-XRT or archival data have allowed associations to be made with known counterparts in other wavelength bands for over 97% of the detections, including the discovery of ∼30 galaxies previously unknown as active galactic nuclei and several new Galactic sources. A total of 266 of the sources are associated with Seyfert galaxies (median redshift z ∼ 0.03) or blazars, with the majority of the remaining sources associated with X-ray binaries in our Galaxy. This ongoing survey is the first uniform all-sky hard X-ray survey since HEAO-1 in 1977. Since the publication of the nine-month BAT survey we have increased the number of energy channels from four to eight and have substantially increased the number of sources with accurate average spectra. The BAT 22 month catalog is the product of the most sensitive all-sky survey in the hard X-ray band, with a detection sensitivity (4.8σ) of 2.2 x 10 -11 erg cm -2 s -1 (1 mCrab) over most of the sky in the 14-195 keV band.

  7. Adaptive Lobster-Eye Hard X-Ray Telescope, Phase I

    Data.gov (United States)

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

  8. kHz femtosecond laser-plasma hard X-ray and fast ion source

    International Nuclear Information System (INIS)

    Thoss, A.; Korn, G.; Stiel, H.; Voigt, U.; Elsaesser, T.; Richardson, M.C.; Siders, C.W.; Faubel, M.

    2002-01-01

    We describe the first demonstration of a new stable, kHz femtosecond laser-plasma source of hard x-ray continuum and K α emission using a thin liquid metallic jet target. kHz femtosecond x-ray sources will find many applications in time-resolved x-ray diffraction and microscopy studies. As high intensity lasers become more compact and operate at increasingly high repetition-rates, they require a target configuration that is both repeatable from shot-to-shot and is debris-free. We have solved this requirement with the use of a fine (10-30 μm diameter) liquid metal jet target that provides a pristine, unperturbed filament surface at rates >100 kHz. A number of liquid metal targets are considered. We will show hard x-ray spectra recorded from liquid Ga targets that show the generation of the 9.3 keV and 10.3 keV, K α and K β lines superimposed on a multi-keV Bremsstrahlung continuum. This source was generated by a 50fs duration, 1 kHz, 2W, high intensity Ti:Sapphire laser. We will discuss the extension of this source to higher powers and higher repetition rates, providing harder x-ray emission, with the incorporation of pulse-shaping and other techniques to enhance the x-ray conversion efficiency. Using the same liquid target technology, we have also demonstrated the generation of forward-going sub-MeV protons from a 10 μm liquid water target at 1 kHz repetition rates. kHz sources of high energy ions will find many applications in time-resolved particle interaction studies, as well as lead to the efficient generation of short-lived isotopes for use in nuclear medicine and other applications. The protons were detected with CR-39 track detectors both in the forward and backward directions up to energies of ∼500 keV. As the intensity of compact high repetition-rate lasers sources increase, we can expect improvements in the energy, conversion efficiency and directionality to occur. The impact of these developments on a number of fields will be discussed. As compact

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

    International Nuclear Information System (INIS)

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

    2011-01-01

    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).

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

    Science.gov (United States)

    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).

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

    Science.gov (United States)

    Scaringi, Simone

    2009-11-01

    Within this thesis are discussed two main topics of contemporary astrophysics. The first is that of machine learning algorithms for astronomy whilst the second is that of magnetic cataclysmic variables (mCVs). To begin, an overview is given of ISINA: INTEGRAL Scouce Identifiction Network Algorithm. This machine learning algorithm, using random forests, is applied to the IBIS/ISGRI data set in order to ease the production of unbiased future soft gamma-ray source catalogues. The feature extraction process on an initial candidate list is described together with feature merging. Three trainng and testing sets are created in order to deal with the diverse time-scales encountered when dealing with the gamma-ray sky: one dealing with faint persistent source recognition, one dealing with strong persistent sources and a final one dealing with transients. For the latter, a new transient detection technique is introduced and described: the transient matrix. Finally the performance of the network is assessed and discussed using the testing set and some illustrative source examples. ISINA is also compared to the more conventional approach of visual inspection. Next mCVs are discussed, and in particular the properties arising from a hard X-ray selected sample which has proven remarkably efficient in detecting intermediate polars and asynchronous polars, two of the rarest type of cataclysmic variables (CVs). This thesis focuses particularly on the link between hard X-ray properties and spin/orbital periods. To this end, a new sample of these objects is constructed by cross-corelating candidate sources detected in INTEGRAL/IBIS observations against catalogues of known CVs. Also included in the analysis are hard X-ray Observations from Swift/BAT and SUZAKU/HXD in order to make the study more complete. It is found that most hard X-ray detected mCVs have Pspin/Porb<0.1 above the period gap. In this respect, attention is given to the very low number of detected systems in any ban

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

    NARCIS (Netherlands)

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

    2007-01-01

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

  13. The hard x-ray imager onboard IXO

    Science.gov (United States)

    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.

  14. Hard x-ray nanoprobe of beamline P06 at PETRA III

    Energy Technology Data Exchange (ETDEWEB)

    Schroer, C. G., E-mail: christian.schroer@desy.de [Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, D-22607 Hamburg (Germany); Department Physik, Universität Hamburg, Luruper Chaussee 149, D-22761 Hamburg (Germany); Baumbach, C. [Institute of Optics and Photonics of Condensed Matter, Technische Universität Chemnitz, D-09126 Chemnitz (Germany); Döhrmann, R.; Kahnt, M.; Reinhardt, J.; Scholz, M.; Schropp, A.; Seyrich, M.; Wittwer, F.; Falkenberg, G. [Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, D-22607 Hamburg (Germany); Klare, S.; Hoppe, R.; Patommel, J.; Ritter, S.; Samberg, D.; Seiboth, F. [Institut für Strukturphysik, Technische Universität Dresden, D-01062 Dresden (Germany)

    2016-07-27

    The hard x-ray scanning microscope at beamline P06 of PETRA III at DESY in Hamburg serves a large user community, from physics, chemistry, and nanotechnology to the bio-medical, materials, environmental, and geosciences. It has been in user operation since 2012, and is mainly based on nanofocusing refractive x-ray lenses. Using refractive optics, nearly gaussian-limited nanobeams in the range from 50 to 100 nm can be generated in the hard x-ray energy range from 8 to 30 keV. The degree of coherence can be traded off against the flux in the nanobeam by a two-stage focusing scheme. We give a brief overview on published results from this instrument and describe its most important components and parameters.

  15. Discovery of Diffuse Hard X-ray Emission associated with Jupiter

    Science.gov (United States)

    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.

  16. New hard X-ray sources at 380 declination

    International Nuclear Information System (INIS)

    Ubertini, P.; Bazzano, A.; La Padula, C.; Polcaro, V.F.

    1981-01-01

    We report the detection of three new hard X-rays sources emitting in the range 15-150 KeV. Their observation was carried out by means of a balloon borne payload, consisting of two large area high spectral resolution Multiwire Spectroscopic Proportional Counters. (orig.)

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

    Science.gov (United States)

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

    2016-01-01

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

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

    Science.gov (United States)

    Gubarev, Mikhail; Ramsey, Brian; Kilaru, Kiranmayee

    2009-01-01

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

  19. The application of thermoluminescence dosimeter on the measurement of hard X-ray pulse energy spectrum

    International Nuclear Information System (INIS)

    Song Zhaohui; Wang Baohui; Wang Kuilu; Hei Dongwei; Sun Fengrong; Li Gang

    2001-01-01

    This paper introduce the application of thermoluminescence dosimeter (TLD) which composed by TLD-3500 Reader and TLD-100M chips on the measurement of hard X-ray pulse energy spectrum. The idea, using Filter Fluorescence Method (FFM) and TLD to measure hard X-ray pulse energy spectrum (from 10 keV to 100 keV), is discussed in details. Considering all the factors of the measuring surroundings, the measurement system of hard X-ray pulse has been devised. The calibration technique of absolute energy response of TLD is established. This method has been applied successfully on the radiation parameters measurement of the huge pulse radiation device -high-power pulser I. Hard X-ray pulse energy spectrum data of the pulser are acquired

  20. Mechanical design of thin-film diamond crystal mounting apparatus for coherence preservation hard x-ray optics

    International Nuclear Information System (INIS)

    Shu, Deming; Shvyd’ko, Yuri V.; Stoupin, Stanislav; Kim, Kwang-Je

    2016-01-01

    A new thin-film diamond crystal mounting apparatus has been designed at the Advanced Photon Source (APS) for coherence preservation hard x-ray optics with optimized thermal contact and minimized crystal strain. This novel mechanical design can be applied to new development in the field of: x-ray optics cavities for hard x-ray free-electron laser oscillators (XFELOs), self-seeding monochromators for hard x-ray free-electron laser (XFEL) with high average thermal loading, high heat load diamond crystal monochromators and beam-sharing/beam-split-and-delay devices for XFEL facilities and future upgraded high-brightness coherent x-ray source in the MBA lattice configuration at the APS.

  1. Mechanical design of thin-film diamond crystal mounting apparatus for coherence preservation hard x-ray optics

    Energy Technology Data Exchange (ETDEWEB)

    Shu, Deming, E-mail: shu@aps.anl.gov; Shvyd’ko, Yuri V.; Stoupin, Stanislav; Kim, Kwang-Je [Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439, U.S.A (United States)

    2016-07-27

    A new thin-film diamond crystal mounting apparatus has been designed at the Advanced Photon Source (APS) for coherence preservation hard x-ray optics with optimized thermal contact and minimized crystal strain. This novel mechanical design can be applied to new development in the field of: x-ray optics cavities for hard x-ray free-electron laser oscillators (XFELOs), self-seeding monochromators for hard x-ray free-electron laser (XFEL) with high average thermal loading, high heat load diamond crystal monochromators and beam-sharing/beam-split-and-delay devices for XFEL facilities and future upgraded high-brightness coherent x-ray source in the MBA lattice configuration at the APS.

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

    Science.gov (United States)

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

    2017-12-01

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

  3. Hard x ray imaging and the relative contribution of thermal and nonthermal emission in flares

    International Nuclear Information System (INIS)

    Holman, G.D.

    1986-01-01

    The question of whether the impulsive 25 to 100 keV x ray emission from solar flares is thermal or nonthermal has been a long-standing controversy. Both thermal and nonthermal (beam) models have been developed and applied to the hard x ray data. It now seems likely that both thermal and nonthermal emission have been observed at hard x ray energies. The Hinotori classification scheme, for example, is an attempt to associate the thermal-nonthermal characteristics of flare hard x ray emission with other flare properties. From a theoretical point of view, it is difficult to generate energetic, nonthermal electrons without dumping an equal or greater amount of energy into plasma heating. On the other hand, any impulsive heating process will invariably generate at least some nonthermal particles. Hence, strictly speaking, although thermal or nonthermal emission may dominate the hard x ray emission in a given energy range for a given flare, there is no such thing as a purely thermal or nonthermal flare mechanism

  4. Relationship between type III-V radio and hard X-ray bursts

    International Nuclear Information System (INIS)

    Stewart, R.T.

    1978-01-01

    Type III-V radio bursts are found to be closely associated with impulsive hard X-ray bursts. Probably 0.1% to 1% of the fast electrons in the X-ray source region escape to heights >0.1 solar radii in the corona and excite the type III-V burst. (Auth.)

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

    Science.gov (United States)

    Robin, David

    2002-04-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-11-14

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

  7. Hard x-ray measurements of the hot-electron rings in EBT-S

    International Nuclear Information System (INIS)

    Hillis, D.L.

    1982-06-01

    A thorough understanding of the hot electron rings in ELMO Bumpy Torus-Scale (EBT-S) is essential to the bumpy torus concept of plasma production, since the rings provide bulk plasma stability. The hot electrons are produced via electron cyclotron resonant heating using a 28-GHz cw gyrotron, which has operated up to power levels of 200 kW. The parameters of the energetic electron rings are studied via hard x-ray measurement techniques and with diamagnetic pickup coils. The hard x-ray measurements have used collimated NaI(Tl) detectors to determine the electron temperature T/sub e/ and electron density n/sub e/ for the hot electron annulus. Typical values of T/sub e/ are 400 to 500 keV and of n/sub e/ 2 to 5 x 10 11 cm -3 . The total stored energy of a single energetic electron ring as measured by diamagnetic pickup loops approaches approx. 40 J and is in good agreement with that deduced from hard x-ray measurements. By combining the experimental measurements from hard x-rays and the diamagnetic loops, an estimate can be obtained for the volume of a single hot electron ring. The ring volume is determined to be approx. 2.2 litres, and this volume remains approximately constant over the T-mode operating regime. Finally, the power in the electrons scattered out of the ring is measured indirectly by measuring the x-ray radiation produced when those electrons strike the chamber walls. The variation of this radiation with increasing microwave power levels is found to be consistent with classical scattering estimates

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

    DEFF Research Database (Denmark)

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

    2015-01-01

    of objects emitting soft X-rays (less than 10 kiloelectronvolts) within the surrounding hundreds of parsecs, as well as the population responsible for unresolved X-ray emission extending along the Galactic plane, is dominated by accreting white dwarf systems. Observations of diffuse hard-X-ray (more than 10...... 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...... 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....

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

    International Nuclear Information System (INIS)

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

    2010-01-01

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

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

    NARCIS (Netherlands)

    de Groot, F.M.F.

    2016-01-01

    In this section we focus on the use of transmission X-ray microscopy (TXM) to measure the XAS spectra. In the last decade a range of soft X-ray and hard X-ray TXM microscopes have been developed, allowing the measurement of XAS spectra with 10–100 nm resolution. In the hard X-ray range the TXM

  11. MODELING THE THERMAL DIFFUSE SOFT AND HARD X-RAY EMISSION IN M17

    International Nuclear Information System (INIS)

    Velázquez, P. F.; Rodríguez-González, A.; Esquivel, A.; Rosado, M.; Reyes-Iturbide, J.

    2013-01-01

    We present numerical models of very young wind driven superbubbles. The parameters chosen for the simulations correspond to the particular case of the M17 nebula, but are appropriate for any young superbubble in which the wind sources have not completely dispersed their parental cloud. From the simulations, we computed the diffuse emission in the soft ([0.5-1.5] keV) and hard ([1.5-5] keV) X-ray bands. The total luminosity in our simulations agrees with the observations of Hyodo et al., about two orders of magnitude below the prediction of the standard model of Weaver et al.. The difference with respect to the standard (adiabatic) model is the inclusion of radiative cooling, which is still important in such young bubbles. We show that for this type of object the diffuse hard X-ray luminosity is significant compared to that of soft X-rays, contributing as much as 10% of the total luminosity, in contrast with more evolved bubbles where the hard X-ray emission is indeed negligible, being at least four orders of magnitude lower than the soft X-ray emission.

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

    DEFF Research Database (Denmark)

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

    2005-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-11-15

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

  14. Modeling of finite systems irradiated by intense ultrashort hard X-ray pulses

    Energy Technology Data Exchange (ETDEWEB)

    Jurek, Zoltan [Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22607 Hamburg (Germany); Ziaja, Beata [Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22607 Hamburg (Germany); Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Krakow (Poland); Santra, Robin [Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22607 Hamburg (Germany); Department of Physics, University of Hamburg, Jungiusstrasse 9, 20355 Hamburg (Germany)

    2013-07-01

    Large number of experiments have already been carried out at the existing hard X-Ray Free-Electron Laser facilities (LCLS, SACLA) during the recent years. Their great success generates even higher anticipation for the forthcoming X-ray sources (European XFEL). Single molecule imaging and nanoplasma formation are the challenging projects with XFELs that investigate the interaction of finite, small objects, e.g. single molecules, atomic clusters with intense X-ray radiation. Accurate modelling of the time evolution of such irradiated systems is required in order to understand the current experiments and to inspire new directions of experimental investigation. In this presentation we report on our theoretical molecular-dynamics tool able to follow non-equilibrium dynamics within finite systems irradiated by intense X-ray pulses. We introduce the relevant physical processes, present computational methods used, discuss their limitations and also the specific constraints on calculations imposed by experimental conditions. Finally, we conclude with a few simulation examples.

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

    CERN Document Server

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

    1999-01-01

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

  16. THE 70 MONTH SWIFT-BAT ALL-SKY HARD X-RAY SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Baumgartner, W. H.; Tueller, J.; Markwardt, C. B.; Skinner, G. K.; Barthelmy, S.; Gehrels, N. [NASA/Goddard Space Flight Center, Astrophysics Science Division, Greenbelt, MD 20771 (United States); Mushotzky, R. F. [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); Evans, P. A., E-mail: whbaumga@alum.mit.edu [X-Ray and Observational Astronomy Group/Department of Physics and Astronomy, University of Leicester, Leicester, LE1 7RH (United Kingdom)

    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.

  17. THE 70 MONTH SWIFT-BAT ALL-SKY HARD X-RAY SURVEY

    International Nuclear Information System (INIS)

    Baumgartner, W. H.; Tueller, J.; Markwardt, C. B.; Skinner, G. K.; Barthelmy, S.; Gehrels, N.; Mushotzky, R. F.; Evans, P. A.

    2013-01-01

    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 4.8σ, 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 × 10 –11 erg s –1 cm –2 over 50% of the sky and 1.34 × 10 –11 erg s –1 cm –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

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

    International Nuclear Information System (INIS)

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

    2013-01-01

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

  19. Time-resolved X-ray studies using third generation synchrotron radiation sources

    International Nuclear Information System (INIS)

    Mills, D.M.

    1991-10-01

    The third generation, high-brilliance, hard x-ray, synchrotron radiation (SR) sources currently under construction (ESRF at Grenoble, France; APS at Argonne, Illinois; and SPring-8 at Harima, Japan) will usher in a new era of x-ray experimentation for both physical and biological sciences. One of the most exciting areas of experimentation will be the extension of x-ray scattering and diffraction techniques to the study of transient or time-evolving systems. The high repetition rate, short-pulse duration, high brilliance, and variable spectral bandwidth of these sources make them ideal for x-ray time-resolved studies. The temporal properties (bunch length, interpulse period, etc.) of these new sources will be summarized. Finally, the scientific potential and the technological challenges of time-resolved x-ray scattering from these new sources will be described. 13 refs., 4 figs

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

    Science.gov (United States)

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

    2017-06-01

    X-ray free-electron lasers enable the investigation of the structure and dynamics of diverse systems, including atoms, molecules, nanocrystals and single bioparticles, under extreme conditions. Many imaging applications that target biological systems and complex materials use hard X-ray pulses with extremely high peak intensities (exceeding 10 20 watts per square centimetre). However, fundamental investigations have focused mainly on the individual response of atoms and small molecules using soft X-rays with much lower intensities. Studies with intense X-ray pulses have shown that irradiated atoms reach a very high degree of ionization, owing to multiphoton absorption, which in a heteronuclear molecular system occurs predominantly locally on a heavy atom (provided that the absorption cross-section of the heavy atom is considerably larger than those of its neighbours) and is followed by efficient redistribution of the induced charge. In serial femtosecond crystallography of biological objects-an application of X-ray free-electron lasers that greatly enhances our ability to determine protein structure-the ionization of heavy atoms increases the local radiation damage that is seen in the diffraction patterns of these objects and has been suggested as a way of phasing the diffraction data. On the basis of experiments using either soft or less-intense hard X-rays, it is thought that the induced charge and associated radiation damage of atoms in polyatomic molecules can be inferred from the charge that is induced in an isolated atom under otherwise comparable irradiation conditions. Here we show that the femtosecond response of small polyatomic molecules that contain one heavy atom to ultra-intense (with intensities approaching 10 20 watts per square centimetre), hard (with photon energies of 8.3 kiloelectronvolts) X-ray pulses is qualitatively different: our experimental and modelling results establish that, under these conditions, the ionization of a molecule is

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

    Science.gov (United States)

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

    2018-04-01

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

  2. Recent advances in synchrotron-based hard x-ray phase contrast imaging

    International Nuclear Information System (INIS)

    Liu, Y; Nelson, J; Andrews, J C; Pianetta, P; Holzner, C

    2013-01-01

    Ever since the first demonstration of phase contrast imaging (PCI) in the 1930s by Frits Zernike, people have realized the significant advantage of phase contrast over conventional absorption-based imaging in terms of sensitivity to ‘transparent’ features within specimens. Thus, x-ray phase contrast imaging (XPCI) holds great potential in studies of soft biological tissues, typically containing low Z elements such as C, H, O and N. Particularly when synchrotron hard x-rays are employed, the favourable brightness, energy tunability, monochromatic characteristics and penetration depth have dramatically enhanced the quality and variety of XPCI methods, which permit detection of the phase shift associated with 3D geometry of relatively large samples in a non-destructive manner. In this paper, we review recent advances in several synchrotron-based hard x-ray XPCI methods. Challenges and key factors in methodological development are discussed, and biological and medical applications are presented. (paper)

  3. Recent advances in synchrotron-based hard x-ray phase contrast imaging

    Science.gov (United States)

    Liu, Y.; Nelson, J.; Holzner, C.; Andrews, J. C.; Pianetta, P.

    2013-12-01

    Ever since the first demonstration of phase contrast imaging (PCI) in the 1930s by Frits Zernike, people have realized the significant advantage of phase contrast over conventional absorption-based imaging in terms of sensitivity to ‘transparent’ features within specimens. Thus, x-ray phase contrast imaging (XPCI) holds great potential in studies of soft biological tissues, typically containing low Z elements such as C, H, O and N. Particularly when synchrotron hard x-rays are employed, the favourable brightness, energy tunability, monochromatic characteristics and penetration depth have dramatically enhanced the quality and variety of XPCI methods, which permit detection of the phase shift associated with 3D geometry of relatively large samples in a non-destructive manner. In this paper, we review recent advances in several synchrotron-based hard x-ray XPCI methods. Challenges and key factors in methodological development are discussed, and biological and medical applications are presented.

  4. Hard X-ray Emission from Galaxy Clusters Observed with INTEGRAL and Prospects for Simbol-X

    Science.gov (United States)

    Eckert, D.; Paltani, S.; Courvoisier, T. J.-L.

    2009-05-01

    Some galaxy clusters are known to contain a large population of relativistic electrons, which produce radio emission through synchrotron radiation. Therefore, it is expected that inverse-Compton scattering of the relativistic electrons with the CMB produce non-thermal emission which should be observable in the hard X-ray domain. Here we focus on the recent results by INTEGRAL, which shed a new light on the non-thermal emission thanks to its angular resolution and sensitivity in the hard X-ray range. We also present the exciting prospects in this field for Simbol-X, which will allow us to detect the non-thermal emission in a number of clusters and map the magnetic field throughout the intra-cluster medium.

  5. SWIFT OBSERVATIONS OF HARD X-RAY EMITTING WHITE DWARFS IN SYMBIOTIC STARS

    International Nuclear Information System (INIS)

    Kennea, J. A.; Burrows, D. N.; Mukai, K.; Markwardt, C. B.; Sokoloski, J. L.; Luna, G. J. M.; Tueller, J.

    2009-01-01

    The X-ray emission from most accreting white dwarfs (WDs) in symbiotic binary stars is quite soft. Several symbiotic WDs, however, produce strong X-ray emission at energies greater than ∼20 keV. The Swift Burst Alert Telescope (BAT) instrument has detected hard X-ray emission from four such accreting WDs in symbiotic stars: RT Cru, T CrB, CD -57 3057, and CH Cyg. In one case (RT Cru), Swift detected X-rays out to greater than 50 keV at >5σ confidence level. Combining data from the X-Ray Telescope (XRT) and BAT detectors, we find that the 0.3-150 keV spectra of RT Cru, T CrB, and CD -57 3057 are well described by emission from a single-temperature, optically thin thermal plasma, plus an unresolved 6.4-6.9 keV Fe line complex. The X-ray spectrum of CH Cyg contains an additional bright soft component. For all four systems, the spectra suffer high levels of absorption from material that both fully and partially covers the source of hard X-rays. The XRT data did not show any of the rapid, periodic variations that one would expect if the X-ray emission were due to accretion onto a rotating, highly magnetized WD. The X-rays were thus more likely from the accretion-disk boundary layer around a massive, non-magnetic WD in each binary. The X-ray emission from RT Cru varied on timescales of a few days. This variability is consistent with being due to changes in the absorber that partially covers the source, suggesting localized absorption from a clumpy medium moving into the line of sight. The X-ray emission from CD -57 3057 and T CrB also varied during the nine months of Swift observations, in a manner that was also consistent with variable absorption.

  6. Signatures of Synchrotron: Low-cutoff X-ray emission and the hard X-ray spectrum of Cas A

    Science.gov (United States)

    Stage, Michael D.; Fedor, Emily Elizabeth; Martina-Hood, Hyourin

    2018-06-01

    In soft X-rays, bright, young Galactic remnants (Cas A, Kepler, Tycho, etc.) present thermal line emission and bremsstrahlung from ejecta, and synchrotron radiation from the shocks. Their hard X-ray spectra tend to be dominated by power-law sources. However, it can be non-trivial to discriminate between contributions from processes such as synchrotron and bremsstrahlung from nonthermally accelerated electrons, even though the energies of the electrons producing this radiation may be very different. Spatially-resolved spectroscopic analysis of 0.5-10 keV observations with, e.g., Chandracan provide leverage in identifying the processes and their locations. Previously, Stage & Allen (2006), Allen & Stage (2007) and Stage & Allen (2011) identified regions characterized by high-cutoff synchrotron radiation. Extrapolating synchrotron model fits to the emission in the Chandra band, they estimated the synchrotron contribution to the hard X-ray spectrum at about one-third the observed flux, fitting the balance with nonthermal bremsstrahlung emission produced by nonthermal electrons in the ejecta. Although it is unlikely this analysis missed regions of the highest-cutoff synchrotron emission, which supplies the bulk of the synchrotron above 15 keV, it may have missed regions of lower-cutoff emission, especially if they are near bright ejecta and the reverse shock. These regions cannot explain the emission at the highest energies (~50 keV), but may make significant contributions to the hard spectrum at lower energies (~10 keV). Using the technique described in Fedor, Martina-Hood & Stage (this meeting), we revisit the analysis to include regions that may be dominated by low-cutoff synchrotron, located in the interior of the remnant, and/or correlated with the reverse shock. Identifying X-ray emission from accelerated electrons associated with the reverse-shock would have important implications for synchrotron and non-thermal bremsstrahlung radiation above the 10 keV.

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

    DEFF Research Database (Denmark)

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

    1997-01-01

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

  8. Scheme for generation of fully-coherent, TW power level hard X-ray pulses from baseline undulators at the European X-ray FEL

    International Nuclear Information System (INIS)

    Geloni, Gianluca; Kocharyan, Vitali; Saldin, Evgeni

    2010-07-01

    The most promising way to increase the output power of an X-ray FEL (XFEL) is by tapering the magnetic field of the undulator. Also, significant increase in power is achievable by starting the FEL process from a monochromatic seed rather than from noise. This report proposes to make use of a cascade self-seeding scheme with wake monochromators in a tunable-gap baseline undulator at the European XFEL to create a source capable of delivering coherent radiation of unprecedented characteristics at hard X-ray wavelengths. Compared with SASE X-ray FEL parameters, the radiation from the new source has three truly unique aspects: complete longitudinal and transverse coherence, and a peak brightness three orders of magnitude higher than what is presently available at LCLS. Additionally, the new source will generate hard X-ray beam at extraordinary peak (TW) and average (kW) power level. The proposed source can thus revolutionize fields like single biomolecule imaging, inelastic scattering and nuclear resonant scattering. The self-seeding scheme with the wake monochromator is extremely compact, and takes almost no cost and time to be implemented. The upgrade proposed in this paper could take place during the commissioning stage of the European XFEL, opening a vast new range of applications from the very beginning of operations.We present feasibility study and examplifications for the SASE2 line of the European XFEL. (orig.)

  9. Magnified hard x-ray microtomography: toward tomography with submicron resolution

    Science.gov (United States)

    Schroer, Christian G.; Benner, Boris; Guenzler, Til F.; Kuhlmann, Marion; Lengeler, Bruno; Rau, Christoph; Weitkamp, Timm; Snigirev, Anatoly A.; Snigireva, Irina

    2002-01-01

    Parabolic compound refractive lenses (PCRLs) are high quality imaging optics for hard x-rays that can be used as an objective lens in a new type of hard x-ray full field microscope. Using an aluminium PCRL, this new type of microscope has been shown to have a resolution of 350 nm. Further improvement of the resolution down to 50 nm can be expected using beryllium as a lens material. The large depth of field (several mm) of the microscope results in sharp projection images for samples that fit into the field of view of about 300 micrometers. This allows to combine magnified imaging with tomographic techniques. First results of magnified microtomography are shown. Contrast formation in the microscope and the consequences for tomographic reconstruction are discussed. An outlook on further developments is given.

  10. Identification of Hard X-ray Sources in Galactic Globular Clusters: Simbol-X Simulations

    Science.gov (United States)

    Servillat, M.

    2009-05-01

    Globular clusters harbour an excess of X-ray sources compared to the number of X-ray sources in the Galactic plane. It has been proposed that many of these X-ray sources are cataclysmic variables that have an intermediate magnetic field, i.e. intermediate polars, which remains to be confirmed and understood. We present here several methods to identify intermediate polars in globular clusters from multiwavelength analysis. First, we report on XMM-Newton, Chandra and HST observations of the very dense Galactic globular cluster NGC 2808. By comparing UV and X-ray properties of the cataclysmic variable candidates, the fraction of intermediate polars in this cluster can be estimated. We also present the optical spectra of two cataclysmic variables in the globular cluster M 22. The HeII (4868 Å) emission line in these spectra could be related to the presence of a magnetic field in these objects. Simulations of Simbol-X observations indicate that the angular resolution is sufficient to study X-ray sources in the core of close, less dense globular clusters, such as M 22. The sensitivity of Simbol-X in an extended energy band up to 80 keV will allow us to discriminate between hard X-ray sources (such as magnetic cataclysmic variables) and soft X-ray sources (such as chromospherically active binaries).

  11. Submicron hard X-ray fluorescence imaging of synthetic elements.

    Science.gov (United States)

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

    2012-04-13

    Synchrotron-based X-ray fluorescence microscopy (XFM) using hard X-rays focused into sub-micron spots is a powerful technique for elemental quantification and mapping, as well as microspectroscopic measurements such as μ-XANES (X-ray absorption near edge structure). We have used XFM to image and simultaneously quantify the transuranic element plutonium at the L(3) or L(2)-edge as well as Th and lighter biologically essential elements in individual rat pheochromocytoma (PC12) cells after exposure to the long-lived plutonium isotope (242)Pu. Elemental maps demonstrate 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 with an incident X-ray energy of 18 keV for an average 202 μm(2) cell is 1.4 fg Pu or 2.9×10(-20) moles Pu μm(-2), which is similar to the detection limit of K-edge XFM 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 L(α) X-ray emission. Copyright © 2012 Elsevier B.V. All rights reserved.

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

    Science.gov (United States)

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

    2000-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-09-01

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

  14. Investigation of pulse shape analyzers for phoswich detectors in space-borne hard X-ray experiments

    Energy Technology Data Exchange (ETDEWEB)

    Bleeker, J A.M.; Overtoom, J M [Huygens Lab., Leiden (Netherlands). Cosmic Ray Working Group

    1979-12-01

    A low-background telescope for hard X-ray astronomy (15-250 keV), comprising arrays of NaI(Tl)/CsI(Na) phoswiches as photon collectors, was recently developed. The background rejection efficiency of such a telescope, and hence the minimum source in a given time, critically depends on the performance of the phoswich pulse shape analyzer (PSA) in a space radiation environment. Results from theoretical and experimental work on analyzer configurations based on zero-crossing detection are presented. This led to the selection of an optimum configuration for space application. The in-situ performance of this analyzer was evaluated in a balloon-borne hard X-ray experiment, showing excellent discrimination efficiency throughout the entire energy regime.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-11-01

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

  16. Simbol-X: Imaging The Hard X-ray Sky with Unprecedented Spatial Resolution and Sensitivity

    Science.gov (United States)

    Tagliaferri, Gianpiero; Simbol-X Joint Scientific Mission Group

    2009-01-01

    Simbol-X is a hard X-ray mission, with imaging capability in the 0.5-80 keV range. It is based on a collaboration between the French and Italian space agencies with participation of German laboratories. The launch is foreseen in late 2014. It relies on a formation flight concept, with two satellites carrying one the mirror module and the other one the focal plane detectors. The mirrors will have a 20 m focal length, while the two focal plane detectors will be put one on top of the other one. This combination will provide over two orders of magnitude improvement in angular resolution and sensitivity in the hard X-ray range with respect to non-focusing techniques. The Simbol-X revolutionary instrumental capabilities will allow us to elucidate outstanding questions in high energy astrophysics such as those related to black-holes accretion physics and census, and to particle acceleration mechanisms. We will give an overall description of the mission characteristics, performances and scientific objectives.

  17. SuperAGILE: The Hard X-ray Imager of AGILE

    International Nuclear Information System (INIS)

    Feroci, M.; Costa, E.; Barbanera, L.; Del Monte, E.; Di Persio, G.; Frutti, M.; Lapshov, I.; Lazzarotto, F.; Pacciani, L.; Porrovecchio, G.; Preger, B.; Rapisarda, M.; Rubini, A.; Soffitta, P.; Tavani, M.; Mastropietro, M.; Morelli, E.; Argan, A.; Ghirlanda, G.; Mereghetti, S.

    2004-01-01

    SuperAGILE is the hard X-ray (10-40 keV) imager for the gamma-ray mission AGILE, currently scheduled for launch in mid-2005. It is based on 4 Si-microstrip detectors, with a total geometric area of 1444 cm 2 (max effective about 300 cm 2 ), equipped with one-dimensional coded masks. The 4 detectors are perpendicularly oriented, in order to provide pairs of orthogonal one-dimensional images of the X-ray sky. The field of view of each 1-D detector is 107 deg. x 68 deg., at zero response, with an overlap in the central 68 deg. x 68 deg. area. The angular resolution on axis is 6 arcmin (pixel size). We present here the current status of the hardware development and the scientific potential for GRBs, for which an onboard trigger and imaging system will allow distributing locations through a fast communication telemetry link from AGILE to the ground

  18. LIFTING THE VEIL ON OBSCURED ACCRETION: ACTIVE GALACTIC NUCLEI NUMBER COUNTS AND SURVEY STRATEGIES FOR IMAGING HARD X-RAY MISSIONS

    International Nuclear Information System (INIS)

    Ballantyne, D. R.; Draper, A. R.; Madsen, K. K.; Rigby, J. R.; Treister, E.

    2011-01-01

    Finding and characterizing the population of active galactic nuclei (AGNs) that produces the X-ray background (XRB) is necessary to connect the history of accretion to observations of galaxy evolution at longer wavelengths. The year 2012 will see the deployment of the first hard X-ray imaging telescope which, through deep extragalactic surveys, will be able to measure the AGN population at the energies where the XRB peaks (∼20-30 keV). Here, we present predictions of AGN number counts in three hard X-ray bandpasses: 6-10 keV, 10-30 keV, and 30-60 keV. Separate predictions are presented for the number counts of Compton thick AGNs, the most heavily obscured active galaxies. The number counts are calculated for five different models of the XRB that differ in the assumed hard X-ray luminosity function, the evolution of the Compton thick AGNs, and the underlying AGN spectral model. The majority of the hard X-ray number counts will be Compton thin AGNs, but there is a greater than tenfold increase in the Compton thick number counts from the 6-10 keV to the 10-30 keV band. The Compton thick population shows enough variation that a hard X-ray number counts measurement will constrain the models. The computed number counts are used to consider various survey strategies for the NuSTAR mission, assuming a total exposure time of 6.2 Ms. We find that multiple surveys will allow a measurement of Compton thick evolution. The predictions presented here should be useful for all future imaging hard X-ray missions.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-09-15

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

  20. Design of a scattering polarimeter for hard X-ray astronomy

    International Nuclear Information System (INIS)

    Costa, E.; Cinti, M.N.; Feroci, M.; Matt, G.; Rapisarda, M.

    1995-01-01

    The design of a new hard X-ray Compton scattering polarimeter based on scintillating fibre technology is presented and studied in detail by means of Monte Carlo calculations. Several different configurations and materials have been tested in order to optimise the sensitivity in the medium/high energy X-ray band. A high sensitivity over the energy band 20-200 keV is obtained for a two material configuration. The advantages deriving from employing a new scintillating material, the YAP (YAlO 3 ), are also discussed. (orig.)

  1. The inner-relationship of hard X-ray and EUV bursts during solar flares

    International Nuclear Information System (INIS)

    Emslie, A.G.; Brown, J.C.; Donnelly, R.F.

    1978-01-01

    A comparison is made between the flux-versus-time profile in the EUV band and the thick target electron flux profile as inferred from hard X-rays for a number of moderately large solar flares. This complements Kane and Donnelly's (1971) study of small flares. The hard X-ray data are from ESRO TD-1A and the EUV inferred from SFD observations. Use of a chi 2 minimising method shows that the best overall fit between the profile fine structures obtains for synchronism to < approximately 5 s which is within the timing accuracy. This suggests that neither conduction nor convection is fast enough as the primary mechanism of energy transport into the EUV flare and rather favours heating by the electrons themselves or by some MHD wave process much faster than acoustic waves. The electron power deposited, for a thick target model, is however far greater than the EUV luminosity for any reasonable assumptions about the area and depth over which EUV is emitted. This means that either most of the power deposited is conducted away to the optical flare or that only a fraction < approximately 1-10% of the X-ray emitting electrons are injected downwards. Recent work on Hα flare heating strongly favours the latter alternative - i.e. that electrons are mostly confined in the corona. (Auth.)

  2. SENSITIVITY OF STACKED IMAGING DETECTORS TO HARD X-RAY POLARIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Muleri, Fabio; Campana, Riccardo, E-mail: fabio.muleri@iaps.inaf.it [INAF-IAPS, Via del Fosso del Cavaliere 100, I-00133 Roma (Italy)

    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.

  3. Hard X-ray full field microscopy and magnifying microtomography using compound refractive lenses

    CERN Document Server

    Schrör, C; Benner, B; Kuhlmann, M; Tümmler, J; Lengeler, B; Rau, C; Weitkamp, T; Snigirev, A; Snigireva, I

    2001-01-01

    For hard X-rays, parabolic compound refractive lenses (PCRLs) are genuine imaging devices like glass lenses for visible light. Based on these new lenses, a hard X-ray full field microscope has been constructed that is ideally suited to image the interior of opaque samples with a minimum of sample preparation. As a result of a large depth of field, CRL micrographs are sharp projection images of most samples. To obtain 3D information about a sample, tomographic techniques are combined with magnified imaging.

  4. Hard X-ray full field microscopy and magnifying microtomography using compound refractive lenses

    Science.gov (United States)

    Schroer, Christian G.; Günzler, Til Florian; Benner, Boris; Kuhlmann, Marion; Tümmler, Johannes; Lengeler, Bruno; Rau, Christoph; Weitkamp, Timm; Snigirev, Anatoly; Snigireva, Irina

    2001-07-01

    For hard X-rays, parabolic compound refractive lenses (PCRLs) are genuine imaging devices like glass lenses for visible light. Based on these new lenses, a hard X-ray full field microscope has been constructed that is ideally suited to image the interior of opaque samples with a minimum of sample preparation. As a result of a large depth of field, CRL micrographs are sharp projection images of most samples. To obtain 3D information about a sample, tomographic techniques are combined with magnified imaging.

  5. Hard X-ray full field microscopy and magnifying microtomography using compound refractive lenses

    International Nuclear Information System (INIS)

    Schroer, Christian G.; Guenzler, Til Florian; Benner, Boris; Kuhlmann, Marion; Tuemmler, Johannes; Lengeler, Bruno; Rau, Christoph; Weitkamp, Timm; Snigirev, Anatoly; Snigireva, Irina

    2001-01-01

    For hard X-rays, parabolic compound refractive lenses (PCRLs) are genuine imaging devices like glass lenses for visible light. Based on these new lenses, a hard X-ray full field microscope has been constructed that is ideally suited to image the interior of opaque samples with a minimum of sample preparation. As a result of a large depth of field, CRL micrographs are sharp projection images of most samples. To obtain 3D information about a sample, tomographic techniques are combined with magnified imaging

  6. Development of Small-Pixel CZT Detectors for Future High-Resolution Hard X-ray Missions

    Science.gov (United States)

    Beilicke, Matthias

    Owing to recent breakthroughs in grazing incidence mirror technology, next-generation hard X-ray telescopes will achieve angular resolutions of between 5 and 10 arc seconds - about an order of magnitude better than that of the NuSTAR hard X-ray telescope. As a consequence, the next generation of hard X-ray telescopes will require pixelated hard X- ray detectors with pixels on a grid with a lattice constant of between 120 and 240 um. Additional detector requirements include a low energy threshold of less than 5 keV and an energy resolution of less than 1 keV. The science drivers for a high angular-resolution hard X-ray mission include studies and measurements of black hole spins, the cosmic evolution of super-massive black holes, AGN feedback, and the behavior of matter at very high densities. We propose a R&D research program to develop, optimize and study the performance of 100-200 um pixel pitch CdTe and Cadmium Zinc Telluride (CZT) detectors of 1-2 mm thickness. Our program aims at a comparison of the performance achieved with CdTe and CZT detectors, and the optimization of the pixel, steering grid, and guard ring anode patterns. Although these studies will use existing ASICs (Application Specific Integrated Circuits), our program also includes modest funds for the development of an ultra-low noise ASIC with a 2-D grid of readout pads that can be directly bonded to the 100-200 um pixel pitch CdTe and CZT detectors. The team includes the Washington University group (Prof. M. Beilicke and Co-I Prof. H.S.W. Krawczynski et al.), and co-investigator G. De Geronimo at Brookhaven National Laboratory (BNL). The Washington University group has a 10 year track record of innovative CZT detector R&D sponsored by the NASA Astronomy and Physics Research and Analysis (APRA) program. The accomplishments to date include the development of CZT detectors with pixel pitches between 350 um and 2.5 mm for the ProtoExist, EXIST, and X-Calibur hard X-ray missions with some of the best

  7. Hard alpha-keratin degradation inside a tissue under high flux X-ray synchrotron micro-beam: a multi-scale time-resolved study.

    Science.gov (United States)

    Leccia, Emilie; Gourrier, Aurélien; Doucet, Jean; Briki, Fatma

    2010-04-01

    X-rays interact strongly with biological organisms. Synchrotron radiation sources deliver very intense X-ray photon fluxes within micro- or submicro cross-section beams, resulting in doses larger than the MGy. The relevance of synchrotron radiation analyses of biological materials is therefore questionable since such doses, million times higher than the ones used in radiotherapy, can cause huge damages in tissues, with regard to not only DNA, but also proteic and lipid organizations. Very few data concerning the effect of very high X-ray doses in tissues are available in the literature. We present here an analysis of the structural phenomena which occur when the model tissue of human hair is irradiated by a synchrotron X-ray micro-beam. The choice of hair is supported by its hierarchical and partially ordered keratin structure which can be analysed inside the tissue by X-ray diffraction. To assess the damages caused by hard X-ray micro-beams (1 microm(2) cross-section), short exposure time scattering SAXS/WAXS patterns have been recorded at beamline ID13 (ESRF) after various irradiation times. Various modifications of the scattering patterns are observed, they provide fine insight of the radiation damages at various hierarchical levels and also unexpectedly provide information about the stability of the various hierarchical structural levels. It appears that the molecular level, i.e. the alpha helices which are stabilized by hydrogen bonds and the alpha-helical coiled coils which are stabilized by hydrophobic interactions, is more sensitive to radiation than the supramolecular architecture of the keratin filament and the filament packing within the keratin associated proteins matrix, which is stabilized by disulphide bonds. (c) 2009 Elsevier Inc. All rights reserved.

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

    DEFF Research Database (Denmark)

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

    2013-01-01

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

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

    Science.gov (United States)

    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

  10. Registration of intensive hard X-rays and soft gamma-rays from the thunderstorm clouds at Tien-Shan installation Adron

    International Nuclear Information System (INIS)

    Antonova, V.P.; Kryukov, S.V.; Vil'danova, L.I.; Gurevich, A.V.; Zybin, K.P.; Kokobaev, M.M.; Nesterova, N.M.; Piskal', V.V.; Ptitsyn, M.O.; Chubenko, A.P.; Shchepetov, A.L.

    2001-01-01

    The Adron installation mounted at the Tien-Shan station is intended for studying the extensive air showers. The Adron installation consists of a neutron supermonitor charged particles detector, muon detector and detector for registering the hard X-ray and soft gamma-radiation from the thunderstorm clouds accomplished on the basis of the Geiger-Mueller counters with sensitivity area of 16-17 m 2 . The intensive fluxes of the hard X-ray and soft gamma-radiation from the thunderstorm clouds passing over the Adron installation at the height below 1 km are registered using this installation. The short-time radiation flares of 1-5 min duration are separated at the background of the intensity slow change. This testifies to the benefit of existence of the runaway electron effect in the thunderstorm clouds [ru

  11. HARD X-RAY TAIL DISCOVERED IN THE CLOCKED BURSTER GS 1826–238

    Energy Technology Data Exchange (ETDEWEB)

    Rodi, J.; Jourdain, E.; Roques, J. P., E-mail: jrodi@irap.omp.eu [Université de Toulouse, UPS-OMP, IRAP, Toulouse (France)

    2016-02-01

    The low-mass X-ray binary (LMXB) neutron star (NS) GS 1826–238 was discovered by Ginga in 1988 September. Due to the presence of quasi-periodicity in the type I X-ray burst rate, the source has been a frequent target of X-ray observations for almost 30 years. Though the bursts were too soft to be detected by INTEGRAL/SPI, the persistent emission from GS 1826–238 was detected over 150 keV during the ∼10 years of observations. Spectral analysis found a significant high-energy excess above a Comptonization model that is well fit by a power law, indicating an additional spectral component. Most previously reported spectra with hard tails in LMXB NS have had an electron temperature of a few keV and a hard tail dominating above ∼50 keV with an index of Γ ∼ 2–3. GS 1826–238 was found to have a markedly different spectrum with kT{sub e} ∼ 20 keV and a hard tail dominating above ∼150 keV with an index of Γ ∼ 1.8, more similar to black hole X-ray binaries. We report on our search for long-term spectral variability over the 25–370 keV energy range and on a comparison of the GS 1826–238 average spectrum to the spectra of other LMXB NSs with hard tails.

  12. NuSTAR Hard X-ray Optics

    DEFF Research Database (Denmark)

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

    2005-01-01

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

  13. New hard X-ray sources at 38/sup 0/ declination

    Energy Technology Data Exchange (ETDEWEB)

    Ubertini, P.; Bazzano, A.; La Padula, C.; Polcaro, V.F. (Consiglio Nazionale delle Ricerche, Frascati (Italy). Lab. di Astrofisica Spaziale)

    1981-01-01

    We report the detection of three new hard X-rays sources emitting in the range 15-150 KeV. Their observation was carried out by means of a balloon borne payload, consisting of two large area high spectral resolution Multiwire Spectroscopic Proportional Counters.

  14. Calibration of hard x-ray (15 - 50 keV) optics at the MPE test facility PANTER

    Science.gov (United States)

    Bräuninger, Heinrich; Burkert, Wolfgang; Hartner, Gisela D.; Citterio, Oberto; Ghigo, Mauro; Mazzoleni, Francesco; Pareschi, Giovanni; Spiga, Daniele

    2004-02-01

    The Max-Planck-Institut für extraterrestrische Physik (MPE) in Garching, Germany, operates the large X-ray beam line facility PANTER for testing astronomical systems. At PANTER a number of telescopes like EXOSAT, ROSAT, SAX, JET-X, ABRIXAS, XMM and SWIFT operating in the soft energy range (0.02 - 15 keV) have been successfully calibrated. In the present paper we report on an important upgrade recently implemented that enables the calibration of hard X-ray optics (from 15 up to 50 keV). Currently hard X-ray optics based on single and multilayer coating are being developed for several future X-ray missions. The hard X-ray calibrations at PANTER are carried out by a high energy source based on an electron gun and several anodes, able to cover the energy range from 4.5 up to 50 keV. It provides fluxes up to 104 counts/sec/cm2 at the instrument chamber with a stability better than 1%. As detector a pn-CCD camera operating between 0.2 and 50 keV and a collecting area of 36 cm2 is used. Taking into account the high energy resolution of the CCD (145 eV at 6 keV), a very easy way to operate the facility in hard X-ray is in energy-dispersive mode (i.e. with a broad-band beam). A double crystal monochromator is also available providing energies up to 20 keV. In this paper we present the first results obtained by using PANTER for hard X-ray characterizations, performed on prototype multilayer optics developed by the Osservatorio Astronomico di Brera (OAB), Milano, Italy, and the Harvard-Smithsonian Center for Astrophysics (CfA), Cambridge, MA, USA.

  15. Hard state neutron star and black hole X-ray binaries in the radio:X-ray luminosity plane

    Science.gov (United States)

    Gallo, Elena; Degenaar, Nathalie; van den Eijnden, Jakob

    2018-05-01

    Motivated by the large body of literature around the phenomenological properties of accreting black hole (BH) and neutron star (NS) X-ray binaries in the radio:X-ray luminosity plane, we carry out a comparative regression analysis on 36 BHs and 41 NSs in hard X-ray states, with data over 7 dex in X-ray luminosity for both. The BHs follow a radio to X-ray (logarithmic) luminosity relation with slope β = 0.59 ± 0.02, consistent with the NSs' slope (β =0.44^{+0.05}_{-0.04}) within 2.5σ. The best-fitting intercept for the BHs significantly exceeds that for the NSs, cementing BHs as more radio loud, by a factor ˜22. This discrepancy can not be fully accounted for by the mass or bolometric correction gap, nor by the NS boundary layer contribution to the X-rays, and is likely to reflect physical differences in the accretion flow efficiency, or the jet powering mechanism. Once importance sampling is implemented to account for the different luminosity distributions, the slopes of the non-pulsating and pulsating NS subsamples are formally inconsistent (>3σ), unless the transitional millisecond pulsars (whose incoherent radio emission mechanism is not firmly established) are excluded from the analysis. We confirm the lack of a robust partitioning of the BH data set into separate luminosity tracks.

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

    DEFF Research Database (Denmark)

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

    2017-01-01

    We present a catalog of hard X-ray sources in a square-degree region surveyed by the Nuclear Spectroscopic Telescope Array (NuSTAR) in the direction of the Norma spiral arm. This survey has a total exposure time of 1.7 Ms, and the typical and maximum exposure depths are 50 ks and 1 Ms, respectively...... model with kT ≈ 15 keV, as observed for the CV candidates....

  17. Pollen structure visualization using high-resolution laboratory-based hard X-ray tomography.

    Science.gov (United States)

    Li, Qiong; Gluch, Jürgen; Krüger, Peter; Gall, Martin; Neinhuis, Christoph; Zschech, Ehrenfried

    2016-10-14

    A laboratory-based X-ray microscope is used to investigate the 3D structure of unstained whole pollen grains. For the first time, high-resolution laboratory-based hard X-ray microscopy is applied to study pollen grains. Based on the efficient acquisition of statistically relevant information-rich images using Zernike phase contrast, both surface- and internal structures of pine pollen - including exine, intine and cellular structures - are clearly visualized. The specific volumes of these structures are calculated from the tomographic data. The systematic three-dimensional study of pollen grains provides morphological and structural information about taxonomic characters that are essential in palynology. Such studies have a direct impact on disciplines such as forestry, agriculture, horticulture, plant breeding and biodiversity. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. CO-ANALYSIS OF SOLAR MICROWAVE AND HARD X-RAY SPECTRAL EVOLUTIONS. I. IN TWO FREQUENCY OR ENERGY RANGES

    International Nuclear Information System (INIS)

    Song Qiwu; Huang Guangli; Nakajima, Hiroshi

    2011-01-01

    Solar microwave and hard X-ray spectral evolutions are co-analyzed in the 2000 June 10 and 2002 April 10 flares, and are simultaneously observed by the Owens-Valley Solar Array in the microwave band and by Yohkoh/Hard X-ray Telescope or RHESSI in the hard X-ray band, with multiple subpeaks in their light curves. The microwave and hard X-ray spectra are fitted by a power law in two frequency ranges of the optical thin part and two photon energy ranges, respectively. Similar to an earlier event in Shao and Huang, the well-known soft-hard-soft pattern of the lower energy range changed to the hard-soft-hard (HSH) pattern of the higher energy range during the spectral evolution of each subpeak in both hard X-ray flares. This energy dependence is actually supported by a positive correlation between the overall light curves and spectral evolution in the lower energy range, while it becomes an anti-correlation in the higher energy range. Regarding microwave data, the HSH pattern appears in the spectral evolution of each subpeak in the lower frequency range, which is somewhat similar to Huang and Nakajima. However, it returns back to the well-known pattern of soft-hard-harder for the overall spectral evolution in the higher frequency range of both events. This frequency dependence is confirmed by an anti-correlation between the overall light curves and spectral evolution in the lower frequency range, but it becomes a positive correlation in the higher frequency range. The possible mechanisms are discussed, respectively, for reasons why hard X-ray and microwave spectral evolutions have different patterns in different energy and frequency intervals.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-06-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Rasouli, C.; Pourshahab, B.; Rasouli, H. [Plasma Physics and Nuclear Fusion Research School, Nuclear Science and Technology Research Institute, AEOI, PO Box 14155-1339, Tehran (Iran, Islamic Republic of); Hosseini Pooya, S. M.; Orouji, T. [Radiation Application Research School, Nuclear Science and Technology Research Institute, AEOI, PO Box 14155-1339, Tehran (Iran, Islamic Republic of)

    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.

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

    DEFF Research Database (Denmark)

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

    2001-01-01

    A planar magnetron sputtering facility has been established at the Danish Space Research Institute (DSRI) for the production coating of depth graded multilayers on the thermally slumped glass segments which form the basis for the hard X-ray telescope on the HEFT balloon project. The facility...

  2. Electronic properties of Nd2−xCexCuO4+δ: A hard X-ray photoemission investigation

    International Nuclear Information System (INIS)

    Guarino, A.; Panaccione, G.; Offi, F.; Monaco, G.; Fondacaro, A.; Torelli, P.; Fittipaldi, R.; Vecchione, A.; Pace, S.; Nigro, A.

    2016-01-01

    Highlights: • We grow and characterize Nd 2−x Ce x CuO 4+δ samples as thin film and single crystal. • We study the Cu 2p levels of our samples by hard X-ray photoemission spectroscopy. • We investigate bulk features of the Nd 2−x Ce x CuO 4+δ samples. • Signature of the bulk response is correlated with the crystallinity of the samples. - Abstract: Cu 2p core levels spectra measured by X-ray photoemission spectroscopy of selected as-grown Nd 2−x Ce x CuO 4+δ samples are presented and discussed. The presence of a satellite peak in the 2p core level of Nd 2−x Ce x CuO 4+δ single crystal by hard X-ray photoemission is confirmed in all non-superconducting samples, films and single crystals investigated in this work. The comparison of the spectral features of the different samples suggests that the presence and the intensity of this satellite peak is not related to the electric transport properties, but to the texture characteristics.

  3. 3D visualization of subcellular structures of Schizosaccharomyces pombe by hard X-ray tomography.

    Science.gov (United States)

    Yang, Y; Li, W; Liu, G; Zhang, X; Chen, J; Wu, W; Guan, Y; Xiong, Y; Tian, Y; Wu, Z

    2010-10-01

    Cellular structures of the fission yeast, Schizosaccharomyces pombe, were examined by using hard X-ray tomography. Since cells are nearly transparent to hard X-rays, Zernike phase contrast and heavy metal staining were introduced to improve image contrast. Through using such methods, images taken at 8 keV displayed sufficient contrast for observing cellular structures. The cell wall, the intracellular organelles and the entire structural organization of the whole cells were visualized in three-dimensional at a resolution better than 100 nm. Comparison between phase contrast and absorption contrast was also made, indicating the obvious advantage of phase contrast for cellular imaging at this energy. Our results demonstrate that hard X-ray tomography with Zernike phase contrast is suitable for cellular imaging. Its unique abilities make it have potential to become a useful tool for revealing structural information from cells, especially thick eukaryotic cells. © 2010 The Authors Journal compilation © 2010 The Royal Microscopical Society.

  4. Sigma observation of the pulsar OAO 1657 - 415: Precise localization at hard X-ray energy and discovery of spin-down

    International Nuclear Information System (INIS)

    Mereghetti, S.; Mandrou, P.; Natalucci, L.; Ballet, J.; Lambert, A.

    1991-01-01

    The region of sky containing the 38 s X-ray pulsar OAO 1657 - 415 has been observed on March 1990 with Sigma, an imaging gamma-ray telescope exploiting the coded mask technique. This observation has yielded an accurate (about arcminute-scale) localization for OAO 1657 - 415 at hard X-ray energy, confirming its association with a previously suggested soft X-ray candidate. A timing analysis of the 40-120 keV data has revealed for the first time a spin-down episode in OAO 1657 - 415, implying that an important change in the accretion torque experienced by this X-ray pulsar must have recently occurred. 18 refs

  5. Radio and X-Ray Observations of the 1998 Outburst of the Recurrent X-Ray Transient 4U 1630-47

    Science.gov (United States)

    Hjellming, R. M.; Rupen, M. P.; Mioduszewski, A. J.; Kuulkers, E.; McCollough, M.; Harmon, B. A.; Buxton, M.; Sood, R.; Tzioumis, A.; Rayner, D.; Dieters, S.; Durouchoux, P.

    1999-03-01

    We report radio (NRAO VLA and Australia Telescope Compact Array), soft X-ray (Rossi X-Ray Timing Explorer ASM), and hard X-ray (Compton Gamma Ray Observatory BATSE) observations of a 1998 outburst in the recurring X-ray transient 4U 1630-47, where radio emission was detected for the first time. The radio observations identify the position of 4U 1630-47 to within 1". Because the radio emission is optically thin with a spectral index of ~-0.8 during the rise, peak, and decay of the initial radio event, the emission is probably coming from an optically thin radio jet ejected over a period of time. The 20-100 keV emission first appeared 1998 January 28 (MJD 50841), the 2-12 keV emission first appeared 1998 February 3 (MJD 50847), and the first radio emission was detected 1998 February 12.6 (MJD 50856.6). The rise of the radio emission probably began about 1998 February 7 (MJD 50851) when the X-rays were in a very hard fluctuating-hardness state, just before changing to a softer, more stable hardness state.

  6. On hard X-ray spectra of accreting neutron stars

    International Nuclear Information System (INIS)

    Zheleznyakov, V.V.

    1982-01-01

    Formation of the spectra of X-ray pulsars and gamma bursters is investigated. Interpretation of a hard X-ray spectrum of pulsars containing cyclotron lines is feasible on the basis of an isothermal model of a polar spot heated due to acccretion to a neutron star. It has been ascertained that in the regions responsible for the formation of continuum radiation and lines the mode polarization is determined by a magnetized vacuum rather than by a plasma. Bearing this in mind, the influence of the magnetic field of a star on the wide wings of the cyclotron line and on its depth is discussed. The part played by the accreting column in the case of strong accretion (approx. equal to 10 19 el cm -3 ) needed for long sustaining of the high level of X-rays from a neutron star-pulsar is studied. There occur the gaps in spectrum at frequencies close to the electron gyro-frequency and its harmonics due to the screening of the hot spot by the opaque gyro-resonant layer located within the accreting column. These gaps ensure the formation of cyclotron lines in absorption irrespective of the presence of such lines in the X-ray spectrum of a polar hot spot. (orig./WL)

  7. Carbon-based Fresnel optics for hard x-ray astronomy.

    Science.gov (United States)

    Braig, Christoph; Zizak, Ivo

    2018-03-10

    We investigate the potential of large-scale diffractive-refractive normal-incidence transmission lenses for the development of space-based hard x-ray telescopes with an angular resolution in the range of (10 -6 -10 -3 )  arcsec over a field of view that is restricted by the available detector size. Coherently stepped achromatic lenses with diameters up to 5 m for compact apertures and 13 m in the case of segmentation provide an access to spectrally resolved imaging within keV-wide bands around the design energy between 10 and 30 keV. Within an integration time of 10 6   s, a photon-limited 5σ sensitivity down to (10 -9 -10 -7 )  s -1  cm -2  keV -1 can be achieved depending on the specific design. An appropriate fabrication strategy, feasible nowadays with micro-optical technologies, is considered and relies on the availability of high-purity carbon or polymer membranes. X-ray fluorescence measurements of various commercially available carbon-based materials prove for most of them the existence of a virtually negligible contamination by critical trace elements such as transition metals on the ppm level.

  8. NuSTAR DETECTION OF HARD X-RAY PHASE LAGS FROM THE ACCRETING PULSAR GS 0834–430

    Energy Technology Data Exchange (ETDEWEB)

    Miyasaka, Hiromasa; Harrison, Fiona A.; Fürst, Felix; Bellm, Eric C.; Grefenstette, Brian W.; Madsen, Kristin K.; Walton, Dominic J. [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Bachetti, Matteo; Barret, Didier [Université de Toulouse, UPS-OMP, IRAP, F-31400 Toulouse (France); Boggs, Steven E.; Craig, William W.; Tomsick, John A. [Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States); Chakrabarty, Deepto [Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Chenevez, Jerome; Christensen, Finn E. [DTU Space, National Space Institute, Technical University of Denmark, Elektrovej 327, DK-2800 Lyngby (Denmark); Hailey, Charles J. [Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); Natalucci, Lorenzo [Istituto di Astrofisica e Planetologia Spaziali, INAF, Via Fosso del Cavaliere 100, Roma I-00133 (Italy); Pottschmidt, Katja [CRESST, UMBC, and NASA GSFC, Code 661, Greenbelt, MD 20771 (United States); Stern, Daniel [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Wilms, Jörn, E-mail: miyasaka@srl.caltech.edu [Dr. Karl-Remeis-Sternwarte and ECAP, Sternwartstr. 7, D-96049 Bamberg (Germany); and others

    2013-09-20

    The Nuclear Spectroscopic Telescope Array hard X-ray telescope observed the transient Be/X-ray binary GS 0834–430 during its 2012 outburst—the first active state of this system observed in the past 19 yr. We performed timing and spectral analysis and measured the X-ray spectrum between 3-79 keV with high statistical significance. We find the phase-averaged spectrum to be consistent with that observed in many other magnetized, accreting pulsars. We fail to detect cyclotron resonance scattering features that would allow us to constrain the pulsar's magnetic field in either phase-averaged or phase-resolved spectra. Timing analysis shows a clearly detected pulse period of ∼12.29 s in all energy bands. The pulse profiles show a strong, energy-dependent hard phase lag of up to 0.3 cycles in phase, or about 4 s. Such dramatic energy-dependent lags in the pulse profile have never before been reported in high-mass X-ray binary pulsars. Previously reported lags have been significantly smaller in phase and restricted to low energies (E < 10 keV). We investigate the possible mechanisms that might produce this energy-dependent pulse phase shift. We find the most likely explanation for this effect is a complex beam geometry.

  9. X-ray holography

    International Nuclear Information System (INIS)

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

    2003-01-01

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

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

    Science.gov (United States)

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

    2013-01-01

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

  11. Measurements of hard cosmic X-rays with special reference to burst phenomena

    International Nuclear Information System (INIS)

    Mills, J.S.

    1978-06-01

    The bulk of this work is concerned with the development and subsequent flights of two balloon-borne gamma-burst detectors. The first was a 1 m 2 device which accumulated a total of 13 1/2 hours flying time at a latitude of 40 0 . The second was a large 7 m 2 detector which was flown from Alice Springs, N. Australia. Both detectors were sensitive to 50 keV to 2 MeV X-rays. The results of these flights are discussed with particular reference to the origin of gamma-bursts. The nature of X-ray bursts is also discussed, together with the results of observations by Experiment F on Ariel V, of the region of the sky centred on the rapid burster MXB1730-335. The last chapter is concerned with the development of a large area hard X-ray detector. This device is designed to be built in modular form and have a total collecting area up to 1 m 2 . It is sensitive to X-rays in the range 20 to 200 keV and is collimated by a tantalum honeycomb which has a field of view of 2 0 FWHM. A small version of this detector was flown on the same platform as the large burst detector. (author)

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

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging Solutions)

    Spectral measurement of Mkn 421 were made in the hard X-ray energy band of ... In the canonical models for blazars, the observed radiation in radio, UV and low ... defined by a slat collimator specially designed with a sandwiched material of.

  13. Study of current oscillations and hard x-ray emissions in pre-cursor phase of major disruptions in Damavand tokamak

    International Nuclear Information System (INIS)

    Amrollahi, R.

    2002-01-01

    We notice that the hard x-ray activity before disruption consists of a series of spikes, uniformly distributed in time domain forming an orderly periodic series of oscillations at a frequency of 6.0 kHz. Disruption starts with an initial fast rise followed by decay. Current decay occurs in two regimes: the first corresponds to slow decay, in which the current is oscillating and reducing down to ∼70% its max value, and the second corresponds to fast decay, in which it totally vanishes abruptly in about 0.2 ms. In the first regime, the loop voltage also oscillates with considerable amplitude. The frequency of oscillations in the first regime is measured to be also about 6.0 kHz. As well, they follow the oscillation phase of hard x-rays. Thus the micro-instabilities driven by runaway electrons, being responsible for the production of hard x-rays bursts and small current oscillations, play a significant role in the disruption. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-11-14

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

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

    NARCIS (Netherlands)

    Kuiper, L.; Hermsen, W.; Méndez, R.M.

    2004-01-01

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

  16. Observation of cosmic hard x-ray by L-3H-9 rocket

    International Nuclear Information System (INIS)

    Hayakawa, Sachio; Makino, Fumiyoshi; Matsui, Yutaka; Fukada, Yutaka.

    1978-01-01

    It has been considered that the isotropic constituents of cosmic hard X-ray have their origins outside the galactic system. As the spectra are uncertain, the generation mechanism of X-ray has not been clearly known yet. It was attempted to make more reliable observation by shutter method and the technique removing charged particles, using the L-3H-8 rocket. The equipment consists of NaI scintillation counter, a front counter, a Xenon counter, a UV sensor, a collimator, a shutter and a shutter-driving device. The L-3H-9 rocket was launched on August 16, 1977, and reached height of 310 km in about 300 seconds. Then the observation was started, but it was not able to observe the isotropic constituents of hard X-ray which were aimed at, as the shutter didn't work normally. It is expected to make another observation with the K-9M-64 rocket in August, 1978, after investigating the action of the shutter and employing and improved driving device. (Kobatake, H.)

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

    Science.gov (United States)

    Mangles, Stuart P. D.

    2012-05-01

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

  18. HOST GALAXY PROPERTIES OF THE SWIFT BAT ULTRA HARD X-RAY SELECTED ACTIVE GALACTIC NUCLEUS

    International Nuclear Information System (INIS)

    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) active galactic nucleus (AGN) with host galaxy optical data to date, with 185 nearby (z * >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] λ5007. 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.

  19. A high time resolution x-ray diagnostic on the Madison Symmetric Torus

    Science.gov (United States)

    DuBois, Ami M.; Lee, John David; Almagri, Abdulgadar F.

    2015-07-01

    A new high time resolution x-ray detector has been installed on the Madison Symmetric Torus (MST) to make measurements around sawtooth events. The detector system is comprised of a silicon avalanche photodiode, a 20 ns Gaussian shaping amplifier, and a 500 MHz digitizer with 14-bit sampling resolution. The fast shaping time diminishes the need to restrict the amount of x-ray flux reaching the detector, limiting the system dead-time. With a much higher time resolution than systems currently in use in high temperature plasma physics experiments, this new detector has the versatility to be used in a variety of discharges with varying flux and the ability to study dynamics on both slow and fast time scales. This paper discusses the new fast x-ray detector recently installed on MST and the improved time resolution capabilities compared to the existing soft and hard x-ray diagnostics. In addition to the detector hardware, improvements to the detector calibration and x-ray pulse identification software, such as additional fitting parameters and a more sophisticated fitting routine are discussed. Finally, initial data taken in both high confinement and standard reversed-field pinch plasma discharges are compared.

  20. Optomechanical Design of a Hard X-ray Nanoprobe Instrument with Nanometer-Scale Active Vibration Control

    International Nuclear Information System (INIS)

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

    2007-01-01

    We are developing a new hard x-ray nanoprobe instrument that is one of the centerpieces of the characterization facilities of the Center for Nanoscale Materials being constructed at Argonne National Laboratory. This new probe will cover an energy range of 3-30 keV with 30-nm spacial resolution. The system is designed to accommodate x-ray optics with a resolution limit of 10 nm, therefore, it requires staging of x-ray optics and specimens with a mechanical repeatability of better than 5 nm. Fast feedback for differential vibration control between the zone-plate x-ray optics and the sample holder has been implemented in the design using a digital-signal-processor-based real-time closed-loop feedback technique. A specially designed, custom-built laser Doppler displacement meter system provides two-dimensional differential displacement measurements with subnanometer resolution between the zone-plate x-ray optics and the sample holder. The optomechanical design of the instrument positioning stage system with nanometer-scale active vibration control is presented in this paper

  1. Scintillation properties and X-ray irradiation hardness of Ce3+-doped Gd2O3-based scintillation glass

    International Nuclear Information System (INIS)

    Liu, Liwan; Shao, Chongyun; Zhang, Yu; Liao, Xili; Yang, Qiuhong; Hu, Lili; Chen, Danping

    2016-01-01

    Ce 3+ -doped Gd 2 O 3 -based scintillation glasses are prepared within an air or CO atmosphere. The effects of fluorine, lutetium, barium, and the melting atmosphere on the optical properties, scintillation properties and irradiation hardness are studied. Absorption spectra, luminescence spectra under UV and X-ray excitation, and the X-ray radiation-induced spectra are presented. The results show that the density can be increased by doping with fluorine, lutetium and barium. The luminescence intensity decreases after X-ray irradiation. Because of charge transfer quenching, fluorine and lutetium enhance the UV-excited and X-ray excited luminescence intensity, but barium decreases. Moreover, fluorine and lutetium are advantageous to irradiation hardness while barium is not. In addition, a non-reducing atmosphere provides a higher irradiation hardness than a reducing atmosphere. Fluorine-doped glass is promising to enhance luminescence intensity, promote irradiation hardness, and increase the density.

  2. Soft x-ray lasers

    International Nuclear Information System (INIS)

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

    1988-01-01

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

  3. CdTe Based Hard X-ray Imager Technology For Space Borne Missions

    Science.gov (United States)

    Limousin, Olivier; Delagnes, E.; Laurent, P.; Lugiez, F.; Gevin, O.; Meuris, A.

    2009-01-01

    CEA Saclay has recently developed an innovative technology for CdTe based Pixelated Hard X-Ray Imagers with high spectral performance and high timing resolution for efficient background rejection when the camera is coupled to an active veto shield. This development has been done in a R&D program supported by CNES (French National Space Agency) and has been optimized towards the Simbol-X mission requirements. In the latter telescope, the hard X-Ray imager is 64 cm² and is equipped with 625µm pitch pixels (16384 independent channels) operating at -40°C in the range of 4 to 80 keV. The camera we demonstrate in this paper consists of a mosaic of 64 independent cameras, divided in 8 independent sectors. Each elementary detection unit, called Caliste, is the hybridization of a 256-pixel Cadmium Telluride (CdTe) detector with full custom front-end electronics into a unique 1 cm² component, juxtaposable on its four sides. Recently, promising results have been obtained from the first micro-camera prototypes called Caliste 64 and will be presented to illustrate the capabilities of the device as well as the expected performance of an instrument based on it. The modular design of Caliste enables to consider extended developments toward IXO type mission, according to its specific scientific requirements.

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

    DEFF Research Database (Denmark)

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

    2011-01-01

    INTEGRAL discovered a new hard X-ray transient, IGR J17498-2921, during the observations performed from 2011-08-11 22:45 to 2011-08-12 05:54 UTC. The source is detected in the IBIS/ISGRI mosaic at a preliminary significance level of 11 and 9 sigma in the 20-40 keV and 40-80 keV energy bands......, respectively. The corresponding fluxes are 19+/-2 and 23+/-3 mCrab (68% c.l., only statistical). The best determined source position is at RA=17:49:49; DEC=-29:21:14 (J2000) with a 90% confinement radius of 2.3 arcmin. The IBIS/ISGRI spectrum (exposure time 15.9 ks) can be well described by a a power...

  5. A novel synthesis of polymeric CO via useful hard X-ray photochemistry

    Directory of Open Access Journals (Sweden)

    Michael Pravica

    2016-12-01

    Full Text Available We report on the synchrotron hard X-ray-induced decomposition of strontium oxalate (SrC2O4 pressurized to 7 GPa inside a diamond anvil cell (DAC. After some 4 h of irradiation in a white X-ray synchrotron beam, a dark reddish/brown region formed in the area of irradiation which was surrounded by a yellowish brown remainder in the rest of the sample. Upon depressurization of the sample to ambient conditions, the reacted/decomposed sample was recoverable as a dark brown/red and yellow waxy solid. Synchrotron infrared spectroscopy confirmed the strong presence of CO2 even under ambient conditions with the sample exposed to air and other strongly absorbing regions, suggesting that the sample may likely be polymerized CO (in part with dispersed CO2 and SrO trapped within the polymer. These results will have significant implications in the ability to readily produce and trap CO2 in situ via irradiation of a simple powder for useful hard X-ray photochemistry and in the ability to easily manufacture polymeric CO (via loading of powders in a DAC or high volume press without the need for the dangerous and complex loading of toxic CO. A novel means of X-ray-induced polymerization under extreme conditions has also been demonstrated.

  6. Design parameters of transmission curved crystal spectrometer for hard X-ray diagnoses

    International Nuclear Information System (INIS)

    Qian Feng; Cao Leifeng; Zhou Weimin; Zhao Zongqing; Gu Yuqiu; Yan Yonghong; Wei Lai; Xiao Shali

    2013-01-01

    The high resolving measurement of hard X-ray spectra generated in laser-produced plasma is usually performed using a cylindrically curved crystal spectrometer. In this paper, theoretical analysis and numerical simulation are performed to investigate the dependence of the energy range and resolving power on various design parameters, including crystal bending radius, source to crystal standoff distance, source size, location of the detector, etc. The investigation provides a means to design and develop cylindrically transmission curved crystal spectrometer which is used in hard X-ray diagnostics. The results show that crystal bending radius has a great influence on energy range of spectra and resolving power, and the separation between the spectral lines increases with the distance behind the focal circle faster than the line width, resulting in increased resolving power with distance. (authors)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-01-28

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

  8. A SUZAKU SEARCH FOR NONTHERMAL EMISSION AT HARD X-RAY ENERGIES IN THE COMA CLUSTER

    International Nuclear Information System (INIS)

    Wik, Daniel R.; Sarazin, Craig L.; Finoguenov, Alexis; Matsushita, Kyoko; Nakazawa, Kazuhiro; Clarke, Tracy E.

    2009-01-01

    The brightest cluster radio halo known resides in the Coma cluster of galaxies. The relativistic electrons producing this diffuse synchrotron emission should also produce inverse Compton emission that becomes competitive with thermal emission from the intracluster medium (ICM) at hard X-ray energies. Thus far, claimed detections of this emission in Coma are controversial. We present a Suzaku HXD-PIN observation of the Coma cluster in order to nail down its nonthermal hard X-ray content. The contribution of thermal emission to the HXD-PIN spectrum is constrained by simultaneously fitting thermal and nonthermal models to it and a spatially equivalent spectrum derived from an XMM-Newton mosaic of the Coma field. We fail to find statistically significant evidence for nonthermal emission in the spectra which are better described by only a single- or multitemperature model for the ICM. Including systematic uncertainties, we derive a 90% upper limit on the flux of nonthermal emission of 6.0 x 10 -12 erg s -1 cm -2 (20-80 keV, for Γ = 2.0), which implies a lower limit on the cluster-averaged magnetic field of B>0.15 μG. Our flux upper limit is 2.5 times lower than the detected nonthermal flux from RXTE and BeppoSAX. However, if the nonthermal hard X-ray emission in Coma is more spatially extended than the observed radio halo, the Suzaku HXD-PIN may miss some fraction of the emission. A detailed investigation indicates that ∼50%-67% of the emission might go undetected, which could make our limit consistent with that of Rephaeli and Gruber and Fusco-Femiano et al. The thermal interpretation of the hard Coma spectrum is consistent with recent analyses of INTEGRAL and Swift data.

  9. Young Stellar Objects from Soft to Hard X-rays

    Science.gov (United States)

    Güdel, Manuel

    2009-05-01

    Magnetically active stars are the sites of efficient particle acceleration and plasma heating, processes that have been studied in detail in the solar corona. Investigation of such processes in young stellar objects is much more challenging due to various absorption processes. There is, however, evidence for violent magnetic energy release in very young stellar objects. The impact on young stellar environments (e.g., circumstellar disk heating and ionization, operation of chemical networks, photoevaporation) may be substantial. Hard X-ray devices like those carried on Simbol-X will establish a basis for detailed studies of these processes.

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

    DEFF Research Database (Denmark)

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

    2014-01-01

    We present results of the point spread function (PSF) calibration of the hard X-ray optics of the Nuclear Spectroscopic Telescope Array (NuSTAR). Immediately post-launch, NuSTAR has observed bright point sources such as Cyg X-1, Vela X-1, and Her X-1 for the PSF calibration. We use the point source...... observations taken at several off-axis angles together with a ray-trace model to characterize the in-orbit angular response, and find that the ray-trace model alone does not fit the observed event distributions and applying empirical corrections to the ray-trace model improves the fit significantly. We...... describe the corrections applied to the ray-trace model and show that the uncertainties in the enclosed energy fraction (EEF) of the new PSF model is less than or similar to 3 for extraction apertures of R greater than or similar to 60" with no significant energy dependence. We also show that the PSF...

  11. The detection of hard x-rays (10-140 KeV) by channel plate electron multipliers

    International Nuclear Information System (INIS)

    Bateman, J.E.

    1976-12-01

    Results are presented indicating that hard X-rays in the energy range 10 to 50 keV can be detected with good efficiency (5 to 10%) in channel plate electron multipliers (CPEM). From 50 keV to 140 keV the detection efficiency lies in the range 1 to 2%. A simple physical model is developed which indicates that not only can good detection efficiency be obtained but that very good X-ray imaging is possible. The model predicts that with further development, a wideband, hard X-ray detector can be realised with a detection efficiency in the range 5 to 20% and spatial response better than 10 lp/mm in the energy range 10 to 140 keV. (author)

  12. Quantitative 3D imaging of yeast by hard X-ray tomography.

    Science.gov (United States)

    Zheng, Ting; Li, Wenjie; Guan, Yong; Song, Xiangxia; Xiong, Ying; Liu, Gang; Tian, Yangchao

    2012-05-01

    Full-field hard X-ray tomography could be used to obtain three-dimensional (3D) nanoscale structures of biological samples. The image of the fission yeast, Schizosaccharomyces pombe, was clearly visualized based on Zernike phase contrast imaging technique and heavy metal staining method at a spatial resolution better than 50 nm at the energy of 8 keV. The distributions and shapes of the organelles during the cell cycle were clearly visualized and two types of organelle were distinguished. The results for cells during various phases were compared and the ratios of organelle volume to cell volume can be analyzed quantitatively. It showed that the ratios remained constant between growth and division phase and increased strongly in stationary phase, following the shape and size of two types of organelles changes. Our results demonstrated that hard X-ray microscopy was a complementary method for imaging and revealing structural information for biological samples. Copyright © 2011 Wiley Periodicals, Inc.

  13. Hard x-ray to low energy gamma ray spectrum of the Crab Nebula

    International Nuclear Information System (INIS)

    Jung, G.V.

    1986-01-01

    The spectrum of the Crab Nebula has been determined in the energy range 10 keV to 5 MeV from the data of the UCSD/MIT Hard-X-ray and Low Energy Gamma Ray Experiment on the first High Energy Astronomy Observatory, HEAO-1. The x-ray to γ-ray portion of the continuous emission from the Crab is indicative of the electron spectrum, its transport through the nebula, and the physical conditions near the shocked interface between the nebular region and the wind which is the physical link between the nebula and the pulsar, NP0532. The power-law dependence of the spectrum found in the lower-energy decade of this observation (10 to 100 keV) is not continued without modification to higher energies. Evidence for this has been accumulating from previous observations in the γ-ray ranges of 1-10 MeV and above 35 MeV. The observations on which this dissertation is based further characterize the spectral change in the 100 keV to 1 MeV region. These observations provide a crucial connection between the x-ray and γ-ray spectrum of the non-pulsed emission of the Crab Nebula. The continuity of this spectrum suggests that the emission mechanism responsible for the non-pulsed γ-rays observed above 35 MeV is of the same origin as the emission at lower energies, i.e. that of synchrotron radiation in the magnetic field of the nebula

  14. An X-ray CCD signal generator with true random arrival time

    International Nuclear Information System (INIS)

    Huo Jia; Xu Yuming; Chen Yong; Cui Weiwei; Li Wei; Zhang Ziliang; Han Dawei; Wang Yusan; Wang Juan

    2011-01-01

    An FPGA-based true random signal generator with adjustable amplitude and exponential distribution of time interval is presented. Since traditional true random number generators (TRNG) are resource costly and difficult to transplant, we employed a method of random number generation based on jitter and phase noise in ring oscillators formed by gates in an FPGA. In order to improve the random characteristics, a combination of two different pseudo-random processing circuits is used for post processing. The effects of the design parameters, such as sample frequency are discussed. Statistical tests indicate that the generator can well simulate the timing behavior of random signals with Poisson distribution. The X-ray CCD signal generator will be used in debugging the CCD readout system of the Low Energy X-ray Instrument onboard the Hard X-ray Modulation Telescope (HXMT). (authors)

  15. Host Galaxy Properties of the Swift BAT Ultra Hard X-Ray Selected AGN

    Science.gov (United States)

    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 (zBAT) 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.

  16. Electronic properties of Nd{sub 2−x}Ce{sub x}CuO{sub 4+δ}: A hard X-ray photoemission investigation

    Energy Technology Data Exchange (ETDEWEB)

    Guarino, A., E-mail: guarino@sa.infn.it [CNR-SPIN-Salerno, Fisciano, SA (Italy); Dipartimento di Fisica “E. R. Caianiello” Università di Salerno, Fisciano, SA (Italy); Panaccione, G. [CNR-IOM Laboratorio TASC, AREA Science Park, 34012 Basovizza, TS (Italy); Offi, F. [CNISM and Dipartimento di Scienze, Università Roma Tre, Roma (Italy); Monaco, G. [Dipartimento di Fisica, Università di Trento, Trento (Italy); Fondacaro, A. [European Synchrotron Radiation Facility, BP 220, F-38042 Grenoble (France); Torelli, P. [CNR-IOM Laboratorio TASC, AREA Science Park, 34012 Basovizza, TS (Italy); Fittipaldi, R.; Vecchione, A. [CNR-SPIN-Salerno, Fisciano, SA (Italy); Pace, S.; Nigro, A. [CNR-SPIN-Salerno, Fisciano, SA (Italy); Dipartimento di Fisica “E. R. Caianiello” Università di Salerno, Fisciano, SA (Italy)

    2016-10-15

    Highlights: • We grow and characterize Nd{sub 2−x}Ce{sub x}CuO{sub 4+δ} samples as thin film and single crystal. • We study the Cu 2p levels of our samples by hard X-ray photoemission spectroscopy. • We investigate bulk features of the Nd{sub 2−x}Ce{sub x}CuO{sub 4+δ} samples. • Signature of the bulk response is correlated with the crystallinity of the samples. - Abstract: Cu 2p core levels spectra measured by X-ray photoemission spectroscopy of selected as-grown Nd{sub 2−x}Ce{sub x}CuO{sub 4+δ} samples are presented and discussed. The presence of a satellite peak in the 2p core level of Nd{sub 2−x}Ce{sub x}CuO{sub 4+δ} single crystal by hard X-ray photoemission is confirmed in all non-superconducting samples, films and single crystals investigated in this work. The comparison of the spectral features of the different samples suggests that the presence and the intensity of this satellite peak is not related to the electric transport properties, but to the texture characteristics.

  17. Advances in indirect detector systems for ultra high-speed hard X-ray imaging with synchrotron light

    Science.gov (United States)

    Olbinado, M. P.; Grenzer, J.; Pradel, P.; De Resseguier, T.; Vagovic, P.; Zdora, M.-C.; Guzenko, V. A.; David, C.; Rack, A.

    2018-04-01

    We report on indirect X-ray detector systems for various full-field, ultra high-speed X-ray imaging methodologies, such as X-ray phase-contrast radiography, diffraction topography, grating interferometry and speckle-based imaging performed at the hard X-ray imaging beamline ID19 of the European Synchrotron—ESRF. Our work highlights the versatility of indirect X-ray detectors to multiple goals such as single synchrotron pulse isolation, multiple-frame recording up to millions frames per second, high efficiency, and high spatial resolution. Besides the technical advancements, potential applications are briefly introduced and discussed.

  18. Extending synchrotron-based atomic physics experiments into the hard X-ray region

    International Nuclear Information System (INIS)

    LeBrun, T.

    1996-01-01

    The high-brightness, hard x-ray beams available from third-generation synchrotron sources are opening new opportunities to study the deepest inner shells of atoms, an area where little work has been done and phenomena not observed in less tightly bound inner-shells are manifested. In addition scattering processes which are weak at lower energies become important, providing another tool to investigate atomic structure as well as an opportunity to study photon/atom interactions beyond photoabsorption. In this contribution the authors discuss some of the issues related to extending synchrotron-based atomic physics experiments into the hard x-ray region from the physical and the experimental point of view. They close with a discussion of a technique, resonant Raman scattering, that may prove invaluable in determining the spectra of the very highly-excited states resulting from the excitation of deep inner shells

  19. High resolution hard X-ray photoemission using synchrotron radiation as an essential tool for characterization of thin solid films

    International Nuclear Information System (INIS)

    Kim, J.J.; Ikenaga, E.; Kobata, M.; Takeuchi, A.; Awaji, M.; Makino, H.; Chen, P.P.; Yamamoto, A.; Matsuoka, T.; Miwa, D.; Nishino, Y.; Yamamoto, T.; Yao, T.; Kobayashi, K.

    2006-01-01

    Recently, we have shown that hard X-ray photoemission spectroscopy using undulator X-rays at SPring-8 is quite feasible with both high resolution and high throughput. Here we report an application of hard X-ray photoemission spectroscopy to the characterization of electronic and chemical states of thin solid films, for which conventional PES is not applicable. As a typical example, we focus on the problem of the scatter in the reported band-gap values for InN. We show that oxygen incorporation into the InN film strongly modifies the valence and plays a crucial role in the band gap problem. The present results demonstrate the powerful applicability of high resolution photoemission spectroscopy with hard X-rays from a synchrotron source

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

    Directory of Open Access Journals (Sweden)

    Andrea Somogyi

    2015-06-01

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

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

    Directory of Open Access Journals (Sweden)

    J. Szlachetko

    2014-03-01

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

  2. Hard-x-ray phase-imaging microscopy using the self-imaging phenomenon of a transmission grating

    International Nuclear Information System (INIS)

    Yashiro, Wataru; Harasse, Sebastien; Momose, Atsushi; Takeuchi, Akihisa; Suzuki, Yoshio

    2010-01-01

    We report on a hard-x-ray imaging microscope consisting of a lens, a sample, and a transmission grating. After the theoretical framework of self-imaging phenomenon by the grating in the system is presented, equations for the electric field on the image plane are derived for ideal and real lenses and an equation for the intensity on the image plane for partially coherent illumination is derived. The equations are simple and similar to those applying to a projection microscope consisting of a transmission grating except that there is no defocusing effect, regardless of whether the grating is in front of or behind the lens. This means that x-ray phase-imaging microscopy can be done without the defocusing effect. It is also shown that, by resolving the self-image on the image plane, high-sensitive x-ray phase-imaging microscopy can be attained without degradation in the spatial resolution due to diffraction by the grating. Experimental results obtained using partially coherent illumination from a synchrotron x-ray source confirm that hard-x-ray phase-imaging microscopy can be quantitatively performed with high sensitivity and without the spatial resolution degradation.

  3. Optomechanical design of a hard x-ray nanoprobe instrument with active vibration control in nanometer scale

    International Nuclear Information System (INIS)

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

    2007-01-01

    We are developing a new hard x-ray nanoprobe instrument that is one of the centerpieces of the characterization facilities of the Center for Nanoscale Materials being constructed at Argonne National Laboratory. This new probe will cover an energy range of 3-30 keV with 30-nm spatial resolution. The system is designed to accommodate x-ray optics with a resolution limit of 10 nm, therefore, it requires staging of x-ray optics and specimens with a mechanical repeatability of better than 5 nm. Fast feedback for differential vibration control between the zone-plate x-ray optics and the sample holder has been implemented in the design using a digital-signal-processor-based real-time closed-loop feedback technique. A specially designed, custom-built laser Doppler displacement meter system provides two-dimensional differential displacement measurements with subnanometer resolution between the zone-plate x-ray optics and the sample holder. The optomechanical design of the instrument positioning stage system with nanometer-scale active vibration control is presented in this paper.

  4. Sub-100 nm hard X-ray microbeam generation with Fresnel zone plate optics

    CERN Document Server

    Takano, H; Takeuchi, A

    2003-01-01

    A hard X-ray focusing test of a Fresnel zone plate has been performed with a synchrotron radiation source at the undulator beamline 20XU of SPring-8. Fresnel zone plate with a radius of 150 mu m, and an outermost zone width of 100 nm was used for the X-ray focusing device. The 248-m-long beamline provides fully coherent illumination for the focusing device. The focused beam evaluated by the knife-edge-scan method and scanning microscope test using test charts. Nearly diffraction- limited focusing with a size of 120 nm was achieved for the first-order diffraction at 10 keV X-ray. Evaluation for the third order diffraction was also performed at 8 keV X-ray, and a focal size of 50 m has been obtained. (author)

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

    DEFF Research Database (Denmark)

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

    2015-01-01

    Referred to by ATel #: 7106, 7136, 7183 Tweet During INTEGRAL Galactic bulge monitoring (e.g., ATel #438) observations performed on UT 2015 February 17 at 12.53-16:45, IBIS/ISGRI detected renewed activity at hard X-rays from a transient within the Globular Cluster NGC 6440. The best determined...

  6. Boron Doped diamond films as electron donors in photovoltaics: An X-ray absorption and hard X-ray photoemission study

    Energy Technology Data Exchange (ETDEWEB)

    Kapilashrami, M.; Zegkinoglou, I. [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Department of Physics, University of Wisconsin Madison, Madison, Wisconsin 53706 (United States); Conti, G.; Nemšák, S.; Conlon, C. S.; Fadley, C. S. [Department of Physics, University of California, Davis, California 95616 (United States); Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Törndahl, T.; Fjällström, V. [Ångström Solar Center, Uppsala University, Box 534, SE-751 21 Uppsala (Sweden); Lischner, J. [Department of Physics, University of California, Berkeley, California 94720 (United States); Louie, Steven G. [Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Department of Physics, University of California, Berkeley, California 94720 (United States); Hamers, R. J.; Zhang, L. [Department of Chemistry, University of Wisconsin Madison, Madison, Wisconsin 53706 (United States); Guo, J.-H. [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Himpsel, F. J., E-mail: fhimpsel@wisc.edu [Department of Physics, University of Wisconsin Madison, Madison, Wisconsin 53706 (United States)

    2014-10-14

    Highly boron-doped diamond films are investigated for their potential as transparent electron donors in solar cells. Specifically, the valence band offset between a diamond film (as electron donor) and Cu(In,Ga)Se₂ (CIGS) as light absorber is determined by a combination of soft X-ray absorption spectroscopy and hard X-ray photoelectron spectroscopy, which is more depth-penetrating than standard soft X-ray photoelectron spectroscopy. In addition, a theoretical analysis of the valence band is performed, based on GW quasiparticle band calculations. The valence band offset is found to be small: VBO=VBM{sub CIGS} – VBM{sub diamond}=0.3 eV±0.1 eV at the CIGS/Diamond interface and 0.0 eV±0.1 eV from CIGS to bulk diamond. These results provide a promising starting point for optimizing the band offset by choosing absorber materials with a slightly lower valence band maximum.

  7. Long duration hard X-ray transatlantic payload

    International Nuclear Information System (INIS)

    La Padula, C.D.; Bazzano, A.; Boccaccini, L.; Mastropietro, M.; Patriarca, R.; Polcaro, V.F.; Ubertini, P.

    1981-01-01

    The HXR80M large-area hard X-ray experiment, to be flown aboard a transatlantic balloon, is described. The detectors are two multiwire spectroscopic proportional counters (MWSPC) with a 2700-sq-cm sensitive area each. The two detectors are filled with an extremely pure xenon-isobutane mixture at high pressure (3-6 atm) in order to obtain good spectral resolution and high efficiency. The onboard data handling is performed by microprocessor-controlled electronics. The scientific aim of the experiment is the survey of the sky belt around the 38th parallel and in particular the observation of faint galactic objects and galactic binary systems in the 15-200 keV range

  8. A novel probe of intrinsic electronic structure: hard X-ray photoemission spectroscopy

    International Nuclear Information System (INIS)

    Takata, Y.; Tamasaku, K.; Nishino, Y.; Miwa, D.; Yabashi, M.; Ikenaga, E.; Horiba, K.; Arita, M.; Shimada, K.; Namatame, H.; Nohira, H.; Hattori, T.; Soedergren, S.; Wannberg, B.; Taniguchi, M.; Shin, S.; Ishikawa, T.; Kobayashi, K.

    2005-01-01

    We have realized hard X-ray (HX) photoemission spectroscopy (PES) with high throughput and high-energy resolution for core level and valence band studies using high-energy and high-brilliance synchrotron radiation at SPring-8. This is a brand new method because large escape depth of high-energy photoelectrons enables us to probe intrinsic bulk states free from surface condition. By use of a newly developed electron energy analyzer and well-focused X-rays, high-energy resolution of 75 meV (E/ΔE 79,000) was realized for 5.95 keV photoelectrons

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

    Science.gov (United States)

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

    2010-01-01

    We use the XMM-Newton EPIC-pn instrument in timing mode to extend spectral time-lag studies of hard state black hole X-ray binaries into the soft X-ray band. \\Ve show that variations of the disc blackbody emission substantially lead variations in the power-law emission, by tenths of a second on variability time-scales of seconds or longer. The large lags cannot be explained by Compton scattering but are consistent with time-delays due to viscous propagation of mass accretion fluctuations in the disc. However, on time-scales less than a second the disc lags the power-law variations by a few ms, consistent with the disc variations being dominated by X-ray heating by the power-law, with the short lag corresponding to the light-travel time between the power-law emitting region and the disc. Our results indicate that instabilities in the accretion disc are responsible for continuum variability on time-scales of seconds or longer and probably also on shorter time-scales.

  10. VLBI OBSERVATION OF MICROQUASAR CYG X-3 DURING AN X-RAY STATE TRANSITION FROM SOFT TO HARD IN THE 2007 MAY-JUNE FLARE

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jeong-Sook; Kim, Sang Joon [School of Space Science, Kyunghee University, Seocheon-dong, Giheung-si, Gyeonggi-do 446-701 (Korea, Republic of); Kim, Soon-Wook [Korea Astronomy and Space Science Institute, 776 Daedeokdaero, Yuseong, Daejeon 305-348 (Korea, Republic of); Kurayama, Tomoharu [Graduate School of Science and Engineering, Kagoshima University, 1-21-35 Korimoto, Kagoshima, Kagoshima 890-0065 (Japan); Honma, Mareki [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Sasao, Tetsuo, E-mail: evony@kasi.re.kr, E-mail: skim@kasi.re.kr [Yaeyama Star Club, Ookawa, Ishigaki, Okinawa 904-0022 (Japan)

    2013-07-20

    We present a radio observation of microquasar Cyg X-3 during an X-ray state transition from ultrasoft to hard state in the 2007 May-June flare using the VLBI Exploration of Radio Astrometry at 22 GHz. During the transition, a short-lived mini-flare of {approx}< 3 hr was detected prior to the major flare. In such a transition, a jet ejection is believed to occur, but there have been no direct observations to support it. An analysis of Gaussian fits to the observed visibility amplitudes shows a time variation of the source axis, or a structural change, during the mini-flare. Our model fits, together with other multiwavelength observations in the radio, soft, and hard X-rays, and the shock-in-jet models for other flaring activities at GHz wavebands, suggest a high possibility of synchrotron flares during the mini-flare, indicative of a predominant contribution from jet activity. Therefore, the mini-flare with an associated structural change is indicative of a jet ejection event in the state transition from ultrasoft to hard state.

  11. Development of hard X-ray spectrometer with high time resolution on the J-TEXT tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Ma, T.K.; Chen, Z.Y., E-mail: zychen@hust.edu.cn; Huang, D.W.; Tong, R.H.; Yan, W.; Wang, S.Y.; Dai, A.J.; Wang, X.L.

    2017-06-01

    A hard X-ray (HXR) spectrometer has been developed to study the runaway electrons during the sawtooth activities and during the runaway current plateau phase on the J-TEXT tokamak. The spectrometer system contains four NaI scintillator detectors and a multi-channel analyzer (MCA) with 0.5 ms time resolution. The dedicated peak detection circuit embedded in the MCA provides a pulse height analysis at count rate up to 1.2 million counts per second (Mcps), which is the key to reach the high time resolution. The accuracy and reliability of the system have been verified by comparing with the hardware integrator of HXR flux. The temporal evolution of HXR flux in different energy ranges can be obtained with high time resolution by this dedicated HXR spectrometer. The response of runaway electron transport with different energy during the sawtooth activities can be studied. The energy evolution of runaway electrons during the plateau phase of runaway current can be obtained. - Highlights: • A HXR spectrometer with high time resolution has been developed on J-TEXT tokamak. • The response of REs transport during the sawtooth activities can be investigated. • The energy evolution of REs following the disruptions can be monitored.

  12. X-ray time lags in PG 1211+143

    Science.gov (United States)

    Lobban, A. P.; Vaughan, S.; Pounds, K.; Reeves, J. N.

    2018-05-01

    We investigate the X-ray time lags of a recent ˜630 ks XMM-Newton observation of PG 1211+143. We find well-correlated variations across the XMM-Newton EPIC bandpass, with the first detection of a hard lag in this source with a mean time delay of up to ˜3 ks at the lowest frequencies. We find that the energy-dependence of the low-frequency hard lag scales approximately linearly with log(E) when averaged over all orbits, consistent with the propagating fluctuations model. However, we find that the low-frequency lag behaviour becomes more complex on time-scales longer than a single orbit, suggestive of additional modes of variability. We also detect a high-frequency soft lag at ˜10-4 Hz with the magnitude of the delay peaking at ≲ 0.8 ks, consistent with previous observations, which we discuss in terms of small-scale reverberation.

  13. Probing deeper by hard x-ray photoelectron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Risterucci, P.; Renault, O., E-mail: olivier.renault@cea.fr; Martinez, E.; Delaye, V. [CEA, LETI, MINATEC Campus, 38054 Grenoble Cedex 09 (France); Detlefs, B. [CEA, LETI, MINATEC Campus, 38054 Grenoble Cedex 09 (France); European Synchrotron Radiation Facility, 6 rue Jules Horowitz, F-38043 Grenoble (France); Zegenhagen, J. [European Synchrotron Radiation Facility, 6 rue Jules Horowitz, F-38043 Grenoble (France); Gaumer, C. [STMicroelectronics, 850 rue Jean Monnet, 38926 Crolles (France); Grenet, G. [Institut des Nanotechnologies de Lyon (INL), UMR CNRS 5270, Ecole Centrale de Lyon, 36, avenue Guy de Collongue 69 134 Ecully Cedex (France); Tougaard, S. [Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, DK-5230 Odense M (Denmark)

    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.

  14. A diamond detector for inertial confinement fusion X-ray bang-time measurements at the National Ignition Facility

    Energy Technology Data Exchange (ETDEWEB)

    MacPhee, A G; Brown, C; Burns, S; Celeste, J; Glenzer, S H; Hey, D; Jones, O S; Landen, O; Mackinnon, A J; Meezan, N; Parker, J; Edgell, D; Glebov, V Y; Kilkenny, J; Kimbrough, J

    2010-11-09

    An instrument has been developed to measure X-ray bang-time for inertial confinement fusion capsules; the time interval between the start of the laser pulse and peak X-ray emission from the fuel core. The instrument comprises chemical vapor deposited polycrystalline diamond photoconductive X-ray detectors with highly ordered pyrolytic graphite X-ray monochromator crystals at the input. Capsule bang-time can be measured in the presence of relatively high thermal and hard X-ray background components due to the selective band pass of the crystals combined with direct and indirect X-ray shielding of the detector elements. A five channel system is being commissioned at the National Ignition Facility at Lawrence Livermore National Laboratory for implosion optimization measurements as part of the National Ignition Campaign. Characteristics of the instrument have been measured demonstrating that X-ray bang-time can be measured with {+-} 30ps precision, characterizing the soft X-ray drive to +/- 1eV or 1.5%.

  15. Modeling Flare Hard X-ray Emission from Electrons in Contracting Magnetic Islands

    Science.gov (United States)

    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.

  16. Development of a hard x-ray wavefront sensor for the EuXFEL

    Science.gov (United States)

    Berujon, Sebastien; Ziegler, Eric; Cojocaru, Ruxandra; Martin, Thierry

    2017-05-01

    We present developments on a hard X-ray wavefront sensing instrument for characterizing and monitoring the beam of the European X-ray Free Electron Lasers (EuXFEL). The pulsed nature of the intense X-ray beam delivered by this new class of facility gives rise to strong challenges for the optics and their diagnostic. In the frame of the EUCALL project Work Package 7, we are developing a sensor able to observe the beam in the X-ray energy range [8-40] keV without altering it. The sensor is based on the speckle tracking principle and employs two semi-transparent optics optimized such that their X-ray absorption is reduced. Furthermore, this instrument requires a scattering object with small random features placed in the beam and two cameras to record images of the beam at two different propagation distances. The analysis of the speckle pattern and its distortion from one image to the other allows absolute or differential wavefront recovery from pulse to pulse. Herein, we introduce the stakes and challenges of wavefront sensing at an XFEL source and explain the strategies adopted to fulfil the high requirements set by such a source.

  17. A FOURIER-TRANSFORMED BREMSSTRAHLUNG FLASH MODEL FOR THE PRODUCTION OF X-RAY TIME LAGS IN ACCRETING BLACK HOLE SOURCES

    International Nuclear Information System (INIS)

    Kroon, John J.; Becker, Peter A.

    2014-01-01

    Accreting black hole sources show a wide variety of rapid time variability, including the manifestation of time lags during X-ray transients, in which a delay (phase shift) is observed between the Fourier components of the hard and soft spectra. Despite a large body of observational evidence for time lags, no fundamental physical explanation for the origin of this phenomenon has been presented. We develop a new theoretical model for the production of X-ray time lags based on an exact analytical solution for the Fourier transform describing the diffusion and Comptonization of seed photons propagating through a spherical corona. The resulting Green's function can be convolved with any source distribution to compute the associated Fourier transform and time lags, hence allowing us to explore a wide variety of injection scenarios. We show that thermal Comptonization is able to self-consistently explain both the X-ray time lags and the steady-state (quiescent) X-ray spectrum observed in the low-hard state of Cyg X-1. The reprocessing of bremsstrahlung seed photons produces X-ray time lags that diminish with increasing Fourier frequency, in agreement with the observations for a wide range of sources

  18. Boron Doped diamond films as electron donors in photovoltaics: An X-ray absorption and hard X-ray photoemission study

    International Nuclear Information System (INIS)

    Kapilashrami, M.; Zegkinoglou, I.; Conti, G.; Nemšák, S.; Conlon, C. S.; Fadley, C. S.; Törndahl, T.; Fjällström, V.; Lischner, J.; Louie, Steven G.; Hamers, R. J.; Zhang, L.; Guo, J.-H.; Himpsel, F. J.

    2014-01-01

    Highly boron-doped diamond films are investigated for their potential as transparent electron donors in solar cells. Specifically, the valence band offset between a diamond film (as electron donor) and Cu(In,Ga)Se 2 (CIGS) as light absorber is determined by a combination of soft X-ray absorption spectroscopy and hard X-ray photoelectron spectroscopy, which is more depth-penetrating than standard soft X-ray photoelectron spectroscopy. In addition, a theoretical analysis of the valence band is performed, based on GW quasiparticle band calculations. The valence band offset is found to be small: VBO = VBM CIGS – VBM diamond  = 0.3 eV ± 0.1 eV at the CIGS/Diamond interface and 0.0 eV ± 0.1 eV from CIGS to bulk diamond. These results provide a promising starting point for optimizing the band offset by choosing absorber materials with a slightly lower valence band maximum.

  19. Cryogenic radiometry in the hard X-ray range

    International Nuclear Information System (INIS)

    Gerlach, M.; Krumrey, M.; Cibik, L.; Muller, P.; Rabus, H.; Ulm, G.

    2008-01-01

    For many applications in radiometry, spectroscopy or astrophysics, absolute measurement of radiant power with low uncertainty is essential. Cryogenic electrical substitution radiometers (ESRs) are regarded as the highest-accuracy primary standard detector in radiometry, from the infrared to the ultraviolet region; in combination with tuneable monochromatized synchrotron radiation from electron storage rings, their range of operation has been extended to the soft x-ray region. ESRs are absolute thermal detectors, based on the equivalence of electrical power and radiant power that can be traced back to electrical SI units and be measured with low uncertainties. Their core piece is a cavity absorber, which is typically made of copper to achieve a short response time suitable for use with synchrotron radiation. At higher photon energies, the use of copper prevents the operation of ESRs due to increasing transmittance. A new absorber design for hard x-rays has been developed at the laboratory of the Physikalisch-Technische Bundesanstalt (PTB) at the electron storage ring BESSY II. The Monte Carlo simulation code Geant4 was applied to optimize its absorptance for photon energies of up to 60 keV, resulting in a cavity absorber with a gold base and a cylindrical shell made of copper, in combination with a thermal sensitivity of around 150 mK μW -1 and a time constant of less than 3 min, which is short compared with the lifetime of many hours for the storage ring current. The measurement of the radiant power of monochromatized synchrotron radiation was achieved with relative standard uncertainties of less than 0.2%, covering the entire photon energy range of three beamlines from 50 eV to 60 keV. Monochromatized synchrotron radiation of high spectral purity was used to calibrate silicon photodiodes against the ESR for photon energies up to 60 keV with relative standard uncertainties below 0.3%. (authors)

  20. Cryogenic radiometry in the hard X-ray range

    Energy Technology Data Exchange (ETDEWEB)

    Gerlach, M.; Krumrey, M.; Cibik, L.; Muller, P.; Rabus, H.; Ulm, G. [Physikalisch-Technische Bundesanstalt, Braunschweig and Berlin, Berlin (Germany)

    2008-10-15

    For many applications in radiometry, spectroscopy or astrophysics, absolute measurement of radiant power with low uncertainty is essential. Cryogenic electrical substitution radiometers (ESRs) are regarded as the highest-accuracy primary standard detector in radiometry, from the infrared to the ultraviolet region; in combination with tuneable monochromatized synchrotron radiation from electron storage rings, their range of operation has been extended to the soft x-ray region. ESRs are absolute thermal detectors, based on the equivalence of electrical power and radiant power that can be traced back to electrical SI units and be measured with low uncertainties. Their core piece is a cavity absorber, which is typically made of copper to achieve a short response time suitable for use with synchrotron radiation. At higher photon energies, the use of copper prevents the operation of ESRs due to increasing transmittance. A new absorber design for hard x-rays has been developed at the laboratory of the Physikalisch-Technische Bundesanstalt (PTB) at the electron storage ring BESSY II. The Monte Carlo simulation code Geant4 was applied to optimize its absorptance for photon energies of up to 60 keV, resulting in a cavity absorber with a gold base and a cylindrical shell made of copper, in combination with a thermal sensitivity of around 150 mK {mu}W{sup -1} and a time constant of less than 3 min, which is short compared with the lifetime of many hours for the storage ring current. The measurement of the radiant power of monochromatized synchrotron radiation was achieved with relative standard uncertainties of less than 0.2%, covering the entire photon energy range of three beamlines from 50 eV to 60 keV. Monochromatized synchrotron radiation of high spectral purity was used to calibrate silicon photodiodes against the ESR for photon energies up to 60 keV with relative standard uncertainties below 0.3%. (authors)

  1. Cryogenic radiometry in the hard x-ray range

    Science.gov (United States)

    Gerlach, M.; Krumrey, M.; Cibik, L.; Müller, P.; Rabus, H.; Ulm, G.

    2008-10-01

    For many applications in radiometry, spectroscopy or astrophysics, absolute measurement of radiant power with low uncertainty is essential. Cryogenic electrical substitution radiometers (ESRs) are regarded as the highest-accuracy primary standard detector in radiometry, from the infrared to the ultraviolet region; in combination with tuneable monochromatized synchrotron radiation from electron storage rings, their range of operation has been extended to the soft x-ray region. ESRs are absolute thermal detectors, based on the equivalence of electrical power and radiant power that can be traced back to electrical SI units and be measured with low uncertainties. Their core piece is a cavity absorber, which is typically made of copper to achieve a short response time suitable for use with synchrotron radiation. At higher photon energies, the use of copper prevents the operation of ESRs due to increasing transmittance. A new absorber design for hard x-rays has been developed at the laboratory of the Physikalisch-Technische Bundesanstalt (PTB) at the electron storage ring BESSY II. The Monte Carlo simulation code Geant4 was applied to optimize its absorptance for photon energies of up to 60 keV, resulting in a cavity absorber with a gold base and a cylindrical shell made of copper, in combination with a thermal sensitivity of around 150 mK µW-1 and a time constant of less than 3 min, which is short compared with the lifetime of many hours for the storage ring current. The measurement of the radiant power of monochromatized synchrotron radiation was achieved with relative standard uncertainties of less than 0.2%, covering the entire photon energy range of three beamlines from 50 eV to 60 keV. Monochromatized synchrotron radiation of high spectral purity was used to calibrate silicon photodiodes against the ESR for photon energies up to 60 keV with relative standard uncertainties below 0.3%.

  2. Watching proteins function with time-resolved x-ray crystallography

    Science.gov (United States)

    Šrajer, Vukica; Schmidt, Marius

    2017-09-01

    Macromolecular crystallography was immensely successful in the last two decades. To a large degree this success resulted from use of powerful third generation synchrotron x-ray sources. An expansive database of more than 100 000 protein structures, of which many were determined at resolution better than 2 Å, is available today. With this achievement, the spotlight in structural biology is shifting from determination of static structures to elucidating dynamic aspects of protein function. A powerful tool for addressing these aspects is time-resolved crystallography, where a genuine biological function is triggered in the crystal with a goal of capturing molecules in action and determining protein kinetics and structures of intermediates (Schmidt et al 2005a Methods Mol. Biol. 305 115-54, Schmidt 2008 Ultrashort Laser Pulses in Biology and Medicine (Berlin: Springer) pp 201-41, Neutze and Moffat 2012 Curr. Opin. Struct. Biol. 22 651-9, Šrajer 2014 The Future of Dynamic Structural Science (Berlin: Springer) pp 237-51). In this approach, short and intense x-ray pulses are used to probe intermediates in real time and at room temperature, in an ongoing reaction that is initiated synchronously and rapidly in the crystal. Time-resolved macromolecular crystallography with 100 ps time resolution at synchrotron x-ray sources is in its mature phase today, particularly for studies of reversible, light-initiated reactions. The advent of the new free electron lasers for hard x-rays (XFELs; 5-20 keV), which provide exceptionally intense, femtosecond x-ray pulses, marks a new frontier for time-resolved crystallography. The exploration of ultra-fast events becomes possible in high-resolution structural detail, on sub-picosecond time scales (Tenboer et al 2014 Science 346 1242-6, Barends et al 2015 Science 350 445-50, Pande et al 2016 Science 352 725-9). We review here state-of-the-art time-resolved crystallographic experiments both at synchrotrons and XFELs. We also outline

  3. Hard X-ray emission of the luminous infrared galaxy NGC 6240 as observed by NuSTAR

    Science.gov (United States)

    Puccetti, S.; Comastri, A.; Bauer, F. E.; Brandt, W. N.; Fiore, F.; Harrison, F. A.; Luo, B.; Stern, D.; Urry, C. M.; Alexander, D. M.; Annuar, A.; Arévalo, P.; Baloković, M.; Boggs, S. E.; Brightman, M.; Christensen, F. E.; Craig, W. W.; Gandhi, P.; Hailey, C. J.; Koss, M. J.; La Massa, S.; Marinucci, A.; Ricci, C.; Walton, D. J.; Zappacosta, L.; Zhang, W.

    2016-01-01

    We present a broadband (~0.3-70 keV) spectral and temporal analysis of NuSTAR observations of the luminous infrared galaxy NGC 6240 combined with archival Chandra, XMM-Newton, and BeppoSAX data. NGC 6240 is a galaxy in a relatively early merger state with two distinct nuclei separated by ~1.̋5. Previous Chandra observations resolved the two nuclei and showed that they are both active and obscured by Compton-thick material. Although they cannot be resolved by NuSTAR, we were able to clearly detect, for the first time, both the primary and the reflection continuum components thanks to the unprecedented quality of the NuSTAR data at energies >10 keV. The NuSTAR hard X-ray spectrum is dominated by the primary continuum piercing through an absorbing column density which is mildly optically thick to Compton scattering (τ ≃ 1.2, NH ~ 1.5 × 1024 cm-2). We detect moderately hard X-ray (>10 keV) flux variability up to 20% on short (15-20 ks) timescales. The amplitude of the variability is largest at ~30 keV and is likely to originate from the primary continuum of the southern nucleus. Nevertheless, the mean hard X-ray flux on longer timescales (years) is relatively constant. Moreover, the two nuclei remain Compton-thick, although we find evidence of variability in the material along the line of sight with column densities NH ≤ 2 × 1023 cm-2 over long (~3-15 yr) timescales. The observed X-ray emission in the NuSTAR energy range is fully consistent with the sum of the best-fit models of the spatially resolved Chandra spectra of the two nuclei.

  4. X-Ray pictures of the developmental anomalis of the hard dental tissue

    International Nuclear Information System (INIS)

    Cecetkova, A.; Ondrasovicova, J.

    2008-01-01

    Dental anomalies are rare lessions of the hard dental tissue. They are as symptoms varies of the syndromes. They are as follow: hyperdoncia, hypodoncia, oligodoncia, anodoncia, mesiodens, macrodoncia and microdoncia. All of the above anomalis are detected by X-ray diagnostics ( intraoral and extra-oral radiography ). (authors)

  5. Reconnection, Particle Acceleration, and Hard X-ray Emission in Eruptive Solar Flares

    Science.gov (United States)

    Martens, Petrus C.

    1998-11-01

    The frequent occurrence of Hard X-ray emission from the top of flaring loops was one of the discoveries by the Hard X-ray telescope on board the Japanese Yohkoh satellite. I will show how the combined effect of magnetic field convergence and pitch- angle scattering of non-thermal electrons injected at the top of the loop results in the generation of looptop sources with properties akin to those observed by Yohkoh. In addition it is shown that the injection of proton beams in the loop legs, expected from theory, reproduces the observed high temperature ``ridges" in the loop legs by mirroring and energy loss through collisions. I will interpret these numerical results as supporting the now widely accepted model of an erupting magnetic flux tube generating a reconnecting current sheet in its wake, where most of the energy release takes place. The strong similarity with the reconnection observed in the MRX experiment in Princeton will be analyzed in detail.

  6. Thin-film-based scintillators for hard x-ray microimaging detectors: the ScinTAX Project

    Science.gov (United States)

    Rack, A.; Cecilia, A.; Douissard, P.-A.; Dupré, K.; Wesemann, V.; Baumbach, T.; Couchaud, M.; Rochet, X.; Riesemeier, H.; Radtke, M.; Martin, T.

    2014-09-01

    The project ScinTAX developed novel thin scintillating films for the application in high performance X-ray imaging and subsequent introduced new X-ray detectors to the market. To achieve this aim lutetium orthosilicate (LSO) scintillators doped with different activators were grown successfully by liquid phase epitaxy. The high density of LSO (7.4 g/cm3), the effective atomic number (65.2) and the high light yield make this scintillator highly applicable for indirect X-ray detection in which the ionizing radiation is converted into visible light and then registered by a digital detector. A modular indirect detection system has been developed to fully exploit the potential of this thin film scintillator for radiographic and tomographic imaging. The system is compatible for high-resolution imaging with moderate dose as well as adaptable to intense high-dose applications where radiation hard microimaging detectors are required. This proceedings article shall review the achieved performances and technical details on this high-resolution detector system which is now available. A selected example application demonstrates the great potential of the optimized detector system for hard X-ray microimaging, i.e. either to improve image contrast due to the availability of efficient thin crystal films or to reduce the dose to the sample.

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

    DEFF Research Database (Denmark)

    Mori, Kaya; Gotthelf, E. V.; Hailey, Charles J.

    2017-01-01

    −093, is detected up to ~30 keV and is well-described by an absorbed power-law model with a best-fit photon index . A re-analysis of archival Chandra and XMM-Newton data finds that the long-term X-ray flux increase of XMMU J183245−0921539 is (90% C.L.), much less than previously reported. A search for a pulsar spin...... of XMMU J183245−0921539 are most consistent with a non-accreting binary generating synchrotron X-rays from particle acceleration in the shock formed as a result of the pulsar and stellar wind collision. We also report on three nearby hard X-ray sources, one of which may be associated with diffuse emission...

  8. On the Nature of the mHz X-ray Quasi-Periodic Oscillations from Ultraluminous X-ray source M82 X-1: Search for Timing-Spectral Correlations

    Science.gov (United States)

    Pasham, Dheeraj R.; Strohmayer, Tod E.

    2013-01-01

    Using all the archival XMM-Newton X-ray (3-10 keV) observations of the ultraluminous X-ray source (ULX) M82 X-1, we searched for a correlation between its variable mHz quasi-periodic oscillation (QPO) frequency and its hardness ratio (5-10 keV/3-5 keV), an indicator of the energy spectral power-law index. When stellar-mass black holes (StMBHs) exhibit type-C low-frequency QPOs (0.2-15 Hz), the centroid frequency of the QPO is known to correlate with the energy spectral index. The detection of such a correlation would strengthen the identification of M82 X-1's mHz QPOs as type-C and enable a more reliable mass estimate by scaling its QPO frequencies to those of type-C QPOs in StMBHs of known mass.We resolved the count rates and the hardness ratios of M82 X-1 and a nearby bright ULX (source 5/X42.3+59) through surface brightness modeling.We detected QPOs in the frequency range of 36-210 mHz during which M82 X-1's hardness ratio varied from 0.42 to 0.47. Our primary results are (1) that we do not detect any correlation between the mHz QPO frequency and the hardness ratio (a substitute for the energy spectral power-law index) and (2) similar to some accreting X-ray binaries, we find that M82 X-1's mHz QPO frequency increases with its X-ray count rate (Pearson's correlation coefficient = +0.97). The apparent lack of a correlation between the QPO centroid frequency and the hardness ratio poses a challenge to the earlier claims that the mHz QPOs of M82 X-1 are the analogs of the type-C low-frequency QPOs of StMBHs. On the other hand, it is possible that the observed relation between the hardness ratio and the QPO frequency represents the saturated portion of the correlation seen in type-C QPOs of StMBHs-in which case M82 X-1's mHz QPOs can still be analogous to type-C QPOs.

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

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Ming, E-mail: minwu@sandia.gov; Rochau, Greg [Sandia National Laboratory, Albuquerque, New Mexico 87185 (United States); Moy, Ken [Special Technology Laboratories, NSTec, Santa Barbara, California 93111-2335 (United States); Kruschwitz, Craig [National Security Technologies, LLC, Los Alamos Operations, Los Alamos, New Mexico 87544 (United States)

    2014-11-15

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

  10. Hard X-ray emission from accretion shocks around galaxy clusters

    Science.gov (United States)

    Kushnir, Doron; Waxman, Eli

    2010-02-01

    We show that the hard X-ray (HXR) emission observed from several galaxy clusters is consistent with a simple model, in which the nonthermal emission is produced by inverse Compton scattering of cosmic microwave background photons by electrons accelerated in cluster accretion shocks: The dependence of HXR surface brightness on cluster temperature is consistent with that predicted by the model, and the observed HXR luminosity is consistent with the fraction of shock thermal energy deposited in relativistic electrons being lesssim0.1. Alternative models, where the HXR emission is predicted to be correlated with the cluster thermal emission, are disfavored by the data. The implications of our predictions to future HXR observations (e.g. by NuStar, Simbol-X) and to (space/ground based) γ-ray observations (e.g. by Fermi, HESS, MAGIC, VERITAS) are discussed.

  11. Hard X-ray emission from accretion shocks around galaxy clusters

    Energy Technology Data Exchange (ETDEWEB)

    Kushnir, Doron; Waxman, Eli, E-mail: doron.kushnir@weizmann.ac.il, E-mail: eli.waxman@weizmann.ac.il [Physics Faculty, Weizmann Institute of Science, PO Box 26, Rehovot (Israel)

    2010-02-01

    We show that the hard X-ray (HXR) emission observed from several galaxy clusters is consistent with a simple model, in which the nonthermal emission is produced by inverse Compton scattering of cosmic microwave background photons by electrons accelerated in cluster accretion shocks: The dependence of HXR surface brightness on cluster temperature is consistent with that predicted by the model, and the observed HXR luminosity is consistent with the fraction of shock thermal energy deposited in relativistic electrons being ∼<0.1. Alternative models, where the HXR emission is predicted to be correlated with the cluster thermal emission, are disfavored by the data. The implications of our predictions to future HXR observations (e.g. by NuStar, Simbol-X) and to (space/ground based) γ-ray observations (e.g. by Fermi, HESS, MAGIC, VERITAS) are discussed.

  12. Hard X-ray emission from accretion shocks around galaxy clusters

    International Nuclear Information System (INIS)

    Kushnir, Doron; Waxman, Eli

    2010-01-01

    We show that the hard X-ray (HXR) emission observed from several galaxy clusters is consistent with a simple model, in which the nonthermal emission is produced by inverse Compton scattering of cosmic microwave background photons by electrons accelerated in cluster accretion shocks: The dependence of HXR surface brightness on cluster temperature is consistent with that predicted by the model, and the observed HXR luminosity is consistent with the fraction of shock thermal energy deposited in relativistic electrons being ∼<0.1. Alternative models, where the HXR emission is predicted to be correlated with the cluster thermal emission, are disfavored by the data. The implications of our predictions to future HXR observations (e.g. by NuStar, Simbol-X) and to (space/ground based) γ-ray observations (e.g. by Fermi, HESS, MAGIC, VERITAS) are discussed

  13. Hard X-ray photoemission spectroscopy of transition-metal oxide thin films and interfaces

    International Nuclear Information System (INIS)

    Wadati, H.; Fujimori, A.

    2013-01-01

    Highlights: •Photoemission spectroscopy is a powerful technique to study the electronic structures of transition-metal oxides. •Hard X-ray photoemission spectroscopy (HXPES) is a new type of photoemission spectroscopy which can probe bulk states. •HXPES is very suitable for studying oxide thin films such as the composition dependence and the film thickness dependence. -- Abstract: Photoemission spectroscopy is a powerful experimental technique to study the electronic structures of solids, especially of transition-metal oxides. Recently, hard X-ray photoemission spectroscopy (HXPES) has emerged as a more relevant experimental technique to obtain clear information about bulk states. Here, we describe how HXPES can be conveniently applied to study the interesting subjects on oxide thin films such as the composition dependence and the film thickness dependence of the electronic structures and the interfacial electronic structure of multilayers

  14. Polarization and dipole effects in hard X-ray photoelectron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-03-15

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

  15. Searching for Dual AGNs in Galaxy Mergers: Understanding Double-Peaked [O III] and Ultra Hard X-rays as Selection Method

    Science.gov (United States)

    McGurk, Rosalie C.; Max, Claire E.; Medling, Anne; Shields, Gregory A.

    2015-01-01

    When galaxies merge, gas accretes onto both central supermassive black holes. Thus, one expects to see close pairs of active galactic nuclei (AGNs), or dual AGNs, in a fraction of galaxy mergers. However, finding them remains a challenge. The presence of double-peaked [O III] or of ultra hard X-rays have been proposed as techniques to select dual AGNs efficiently. We studied a sample of double-peaked narrow [O III] emitting AGNs from SDSS DR7. By obtaining new and archival high spatial resolution images taken with the Keck 2 Laser Guide Star Adaptive Optics system and the near-infrared (IR) camera NIRC2, we showed that 30% of double-peaked [O III] emission line SDSS AGNs have two spatial components within a 3' radius. However, spatially resolved spectroscopy or X-ray observations are needed to confirm these galaxy pairs as systems containing two AGNs. We followed up these spatially-double candidate dual AGNs with integral field spectroscopy from Keck OSIRIS and Gemini GMOS and with long-slit spectroscopy from Keck NIRSPEC and Shane Kast Double Spectrograph. We find double-peaked emitters are caused sometimes by dual AGN and sometimes by outflows or narrow line kinematics. We also performed Chandra X-ray ACIS-S observations on 12 double-peaked candidate dual AGNs. Using our observations and 8 archival observations, we compare the distribution of X-ray photons to our spatially double near-IR images, measure X-ray luminosities and hardness ratios, and estimate column densities. By assessing what fraction of double-peaked emission line SDSS AGNs are true dual AGNs, we can better determine whether double-peaked [O III] is an efficient dual AGN indicator and constrain the statistics of dual AGNs. A second technique to find dual AGN is the detection of ultra hard X-rays by the Swift Burst Alert Telescope. We use CARMA observations to measure and map the CO(1-0) present in nearby ultra-hard X-ray Active Galactic Nuclei (AGNs) merging with either a quiescent companion

  16. CO-ANALYSIS OF SOLAR MICROWAVE AND HARD X-RAY SPECTRAL EVOLUTIONS. II. IN THREE SOURCES OF A FLARING LOOP

    International Nuclear Information System (INIS)

    Huang Guangli; Li Jianping

    2011-01-01

    Based on the spatially resolvable data of the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) and Nobeyama Radio Heliograph (NoRH), co-analysis of solar hard X-ray and microwave spectral evolution is performed in three separate sources located in one looptop (LT) and two footpoints (FPs) of a huge flaring loop in the 2003 October 24 flare. The RHESSI image spectral evolution in 10-100 keV is always fitted by the well-known soft-hard-soft (SHS) pattern in the three sources. When the total energy is divided into four intervals similar to the Yohkoh/Hard X-ray Telescope, i.e., 12.5-32.5 keV, 32.5-52.5 keV, 52.5-72.5 keV, and 72.5-97.5 keV, the SHS pattern in lower energies is converted gradually to the hard-soft-hard (HSH) pattern in higher energies in all three sources. However, the break energy in the LT and the northeast FP (∼32.5 keV) is evidently smaller than that in the southwest FP (∼72.5 keV). Regarding microwave spectral evolution of the NoRH data, the well-known soft-hard-harder pattern appeared in the southwest FP, while the HSH pattern coexisted in the LT and the northeast FP. The different features of the hard X-ray and microwave spectral evolutions in the three sources may be explained by the loop-loop interaction with another huge loop in the LT and with a compact loop in the northeast FP, where the trapping effect is much stronger than that in the southwest FP. The comparison between the LT and FP spectral indices suggests that the radiation mechanism of X-rays may be quite different in different energy intervals and sources. The calculated electron spectral indices from the predicted mechanisms of X-rays gradually become closer to those from the microwave data with increasing X-ray energies.

  17. Development and application of cryogenic radiometry with hard X-rays; Entwicklung und Anwendung der Kryoradiometrie mit harter Roentgenstrahlung

    Energy Technology Data Exchange (ETDEWEB)

    Gerlach, Martin

    2008-06-06

    To establish cryogenic radiometry with hard X-ray radiation for photon energies of up to 60 keV, a novel type of cavity absorber had to be developed for the cryogenic radiometer SYRES I, which is deployed by the Physikalisch-Technische Bundesanstalt (PTB) as primary standard detector at the electron storage ring BESSY II. This new type of cavity absorber allows for the complete absorption of hard X-ray radiation in combination with an appropriate sensitivity and an adequate time constant for the measurement of synchrotron radiation at BESSY II. As the process of fabrication of different types of absorbers is very time-consuming, the interaction of hard X-ray radiation with different absorber materials and geometries was studied intensively by using the Monte Carlo simulation code Geant4. The accuracy of the simulations was verified comparing them to scattering experiments performed at a wavelength shifter beamline at BESSY II with a calibrated energy dispersive detector. It was shown that Geant4 describes the photo-effect, including fluorescence as well as Compton- and Rayleigh scattering, with high accuracy. The simulations and experiments resulted in a cavity absorber with a gold base 550 {mu}m in thickness and a cylindrical shell made of copper 90 {mu}m in thickness to reduce losses caused by fluorescence and scattered radiation. Monochromatized synchrotron radiation of high spectral purity was then used to calibrate semiconductor photodiodes, which can be used as compact and inexpensive secondary standard detectors, against a cryogenic radiometer, covering the entire photon energy range of three beamlines from 50 eV to 60 keV with relative uncertainties of less than 0.5 %. Furthermore the spatial homogeneity of the spectral responsivity, the transmittance and the linearity of the photodiodes was investigated. Through a direct comparison of the free-air ionization chamber PK100, a primary detector standard of PTB used in dosimetry, and the cryogenic radiometer

  18. Ultrashort hard x-ray pulses generated by 90 degrees Thomson scattering

    International Nuclear Information System (INIS)

    Chin, A.H.; Schoenlein, R.W.; Glover, T.E.

    1997-01-01

    Ultrashort x-ray pulses permit observation of fast structural dynamics in a variety of condensed matter systems. The authors have generated 300 femtosecond, 30 keV x-ray pulses by 90 degrees Thomson scattering between femtosecond laser pulses and relativistic electrons. The x-ray and laser pulses are synchronized on a femtosecond time scale, an important prerequisite for ultrafast pump-probe spectroscopy. Analysis of the x-ray beam properties also allows for electron bunch characterization on a femtosecond time scale

  19. Radio and X-ray observations of a multiple impulsive solar burst with high time resolution

    International Nuclear Information System (INIS)

    Kosugi, T.

    1981-01-01

    A well-developed multiple impulsive microwave burst occurred on February 17, 1979 simultaneously with a hard X-ray burst and a large group of type III bursts at metric wavelengths. The whole event is composed of serveral subgroups of elementary spike bursts. Detailed comparisons between these three classes of emissions with high time resolution of approx. equal to0.5 s reveal that individual type III bursts coincide in time with corresponding elementary X-ray and microwave spike bursts. It suggests that a non-thermal electron pulse generating a type III spike burst is produced simultaneously with those responsible for the corresponding hard X-ray and microwave spike bursts. The rise and decay characteristic time scales of the elementary spike burst are << 1 s, and approx. equal to1 s and approx. equal to3 s for type III, hard X-ray and microwave emissions respectively. Radio interferometric observations made at 17 GHz reveal that the spatial structure varies from one subgroup to others while it remains unchanged in a subgroup. Spectral evolution of the microwave burst seems to be closely related to the spatial evolution. The spatial evolution together with the spectral evolution suggests that the electron-accelerating region shifts to a different location after it stays at one location for several tens of seconds, duration of a subgroup of elementary spike bursts. We discuss several requirements for a model of the impulsive burst which come out from these observational results, and propose a migrating double-source model. (orig.)

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

    International Nuclear Information System (INIS)

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

    1984-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Kumiko Morihana

    2014-12-01

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

  2. STUDYING FAINT ULTRA-HARD X-RAY EMISSION FROM AGN IN GOALS LIRGS WITH SWIFT/BAT

    International Nuclear Information System (INIS)

    Koss, Michael; Casey, Caitlin M.; Mushotzky, Richard; Veilleux, Sylvain; Baumgartner, Wayne; Tueller, Jack; Markwardt, Craig

    2013-01-01

    We present the first analysis of the all-sky Swift Burst Alert Telescope (BAT) ultra-hard X-ray (14-195 keV) data for a targeted list of objects. We find that the BAT data can be studied at three-times-fainter limits than in previous blind detection catalogs based on prior knowledge of source positions and using smaller energy ranges for source detection. We determine the active galactic nucleus (AGN) fraction in 134 nearby (z IR /L ☉ > 11.8) detected. The BAT AGN classification shows 97% (37/38) agreement with Chandra and XMM-Newton AGN classification using hardness ratios or detection of an iron Kα line. This confirms our statistical analysis and supports the use of the Swift/BAT all-sky survey to study fainter populations of any category of sources in the ultra-hard X-ray band. BAT AGNs in LIRGs tend to show higher column densities with 40% ± 9% showing 14-195 keV/2-10 keV hardness flux ratios suggestive of high or Compton-thick column densities (log N H > 24 cm –2 ), compared to only 12% ± 5% of non-LIRG BAT AGNs. We also find that using specific energy ranges of the BAT detector can yield additional sources over total band detections with 24% (5/21) of detections in LIRGs at 24-35 keV not detected at 14-195 keV.

  3. A cryogenic electrical substitution radiometer for hard X-rays

    International Nuclear Information System (INIS)

    Gerlach, M.; Krumrey, M.; Cibik, L.; Mueller, P.; Ulm, G.

    2007-01-01

    Cryogenic electrical substitution radiometers (ESR) are well established in radiometry to determine radiant power with low uncertainties from the infrared to the soft X-ray region. The absorbers are made of copper to achieve a small time constant. At higher photon energies, the use of copper prevents the operation of ESR due to increasing transmittance. A new absorber design for hard X-rays has been developed at the laboratory of the Physikalisch-Technische Bundesanstalt (PTB) at BESSY II. In the first place, extensive simulations were performed for a variety of materials and absorber geometries using the Monte Carlo simulation code Geant4. The accuracy of the simulations was verified comparing them to scattering experiments performed at a 7 T wavelength shifter beamline at BESSY II. It was shown that Geant4 describes the photo-effect, including fluorescence as well as Compton- and Rayleigh scattering, with high accuracy. The simulations and experiments resulted in an absorber with a gold base 500 μm in thickness, inclined by 30 deg., and a cylindrical shell made of copper 80 μm in thickness to reduce losses caused mainly by fluorescence. The absorber was manufactured at PTB by means of electroforming and was implemented into an existing ESR. Monochromatized synchrotron radiation of high spectral purity was used to calibrate silicon photodiodes against the ESR for photon energies up to 60 keV with relative uncertainties below 1%

  4. A cryogenic electrical substitution radiometer for hard X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Gerlach, M. [Physikalisch-Technische Bundesanstalt, Abbestr. 2-12, 10587 Berlin (Germany)], E-mail: Martin.Gerlach@ptb.de; Krumrey, M.; Cibik, L.; Mueller, P.; Ulm, G. [Physikalisch-Technische Bundesanstalt, Abbestr. 2-12, 10587 Berlin (Germany)

    2007-09-21

    Cryogenic electrical substitution radiometers (ESR) are well established in radiometry to determine radiant power with low uncertainties from the infrared to the soft X-ray region. The absorbers are made of copper to achieve a small time constant. At higher photon energies, the use of copper prevents the operation of ESR due to increasing transmittance. A new absorber design for hard X-rays has been developed at the laboratory of the Physikalisch-Technische Bundesanstalt (PTB) at BESSY II. In the first place, extensive simulations were performed for a variety of materials and absorber geometries using the Monte Carlo simulation code Geant4. The accuracy of the simulations was verified comparing them to scattering experiments performed at a 7 T wavelength shifter beamline at BESSY II. It was shown that Geant4 describes the photo-effect, including fluorescence as well as Compton- and Rayleigh scattering, with high accuracy. The simulations and experiments resulted in an absorber with a gold base 500 {mu}m in thickness, inclined by 30 deg., and a cylindrical shell made of copper 80 {mu}m in thickness to reduce losses caused mainly by fluorescence. The absorber was manufactured at PTB by means of electroforming and was implemented into an existing ESR. Monochromatized synchrotron radiation of high spectral purity was used to calibrate silicon photodiodes against the ESR for photon energies up to 60 keV with relative uncertainties below 1%.

  5. A cryogenic electrical substitution radiometer for hard X-rays

    Science.gov (United States)

    Gerlach, M.; Krumrey, M.; Cibik, L.; Müller, P.; Ulm, G.

    2007-09-01

    Cryogenic electrical substitution radiometers (ESR) are well established in radiometry to determine radiant power with low uncertainties from the infrared to the soft X-ray region. The absorbers are made of copper to achieve a small time constant. At higher photon energies, the use of copper prevents the operation of ESR due to increasing transmittance. A new absorber design for hard X-rays has been developed at the laboratory of the Physikalisch-Technische Bundesanstalt (PTB) at BESSY II. In the first place, extensive simulations were performed for a variety of materials and absorber geometries using the Monte Carlo simulation code Geant4. The accuracy of the simulations was verified comparing them to scattering experiments performed at a 7 T wavelength shifter beamline at BESSY II. It was shown that Geant4 describes the photo-effect, including fluorescence as well as Compton- and Rayleigh scattering, with high accuracy. The simulations and experiments resulted in an absorber with a gold base 500 μm in thickness, inclined by 30°, and a cylindrical shell made of copper 80 μm in thickness to reduce losses caused mainly by fluorescence. The absorber was manufactured at PTB by means of electroforming and was implemented into an existing ESR. Monochromatized synchrotron radiation of high spectral purity was used to calibrate silicon photodiodes against the ESR for photon energies up to 60 keV with relative uncertainties below 1%.

  6. Time variability of X-ray binaries: observations with INTEGRAL. Modeling

    International Nuclear Information System (INIS)

    Cabanac, Clement

    2007-01-01

    The exact origin of the observed X and Gamma ray variability in X-ray binaries is still an open debate in high energy astrophysics. Among others, these objects are showing aperiodic and quasi-periodic luminosity variations on timescales as small as the millisecond. This erratic behavior must put constraints on the proposed emission processes occurring in the vicinity of the neutrons star or the stellar mass black-hole held by these objects. We propose here to study their behavior following 3 different ways: first we examine the evolution of a particular X-ray source discovered by INTEGRAL, IGR J19140+0951. Using timing and spectral data given by different instruments, we show that the source type is plausibly consistent with a High Mass X-ray Binary hosting a neutrons star. Subsequently, we propose a new method dedicated to the study of timing data coming from coded mask aperture instruments. Using it on INTEGRAL/ISGRI real data, we detect the presence of periodic and quasi-periodic features in some pulsars and micro-quasars at energies as high as a hundred keV. Finally, we suggest a model designed to describe the low frequency variability of X-ray binaries in their hardest state. This model is based on thermal comptonization of soft photons by a warm corona in which a pressure wave is propagating in cylindrical geometry. By computing both numerical simulations and analytical solution, we show that this model should be suitable to describe some of the typical features observed in X-ray binaries power spectra in their hard state and their evolution such as aperiodic noise and low frequency quasi-periodic oscillations. (author) [fr

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

    International Nuclear Information System (INIS)

    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

    A nested Kirkpatrick–Baez mirror pair has been designed, fabricated and tested for achromatic nanofocusing synchrotron hard X-rays. The prototype system achieved a FWHM focal spot of about 150 nm in both horizontal and vertical directions. 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

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

    DEFF Research Database (Denmark)

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

    2017-01-01

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

  9. Behavior of hard X-ray emission in discharges with current disruptions in the DAMAVAND and TVD tokamaks

    International Nuclear Information System (INIS)

    Farshi, E.; Amrollahy, R.; Bortnikov, A.V.; Brevnov, N.N.; Gott, Yu.V.; Shurygin, V.A.

    2001-01-01

    Results are presented from studies of the behavior of hard X-ray emission in discharges with current disruptions in the DAMAVAND and TVD tokamaks. The current disruptions are caused by either an MHD instability or the instability related to the vertical displacement of the plasma column. Experiments were conducted at a fixed value of the safety factor at the plasma boundary (q a ≅ 2.3). Experimental data show that, during a disruption caused by an MHD instability, hard X-ray emission is suppressed by this instability if the amplitude of the magnetic field fluctuations exceeds a certain level. If the disruption is caused by the instability related to the vertical displacement of the plasma column, then hard X-ray emission is observed at the instant of disruption. The experimental results show that the physical processes resulting in the generation and suppression of runaway electron beams are almost identical in large and small tokamaks

  10. Calibration of the Gamma-RAy Polarimeter Experiment (GRAPE) at a polarized hard X-ray beam

    International Nuclear Information System (INIS)

    Bloser, P.F.; Legere, J.S.; McConnell, M.L.; Macri, J.R.; Bancroft, C.M.; Connor, T.P.; Ryan, J.M.

    2009-01-01

    The Gamma-RAy Polarimeter Experiment (GRAPE) is a concept for an astronomical hard X-ray Compton polarimeter operating in the 50-500 keV energy band. The instrument has been optimized for wide-field polarization measurements of transient outbursts from energetic astrophysical objects such as gamma-ray bursts and solar flares. The GRAPE instrument is composed of identical modules, each of which consists of an array of scintillator elements read out by a multi-anode photomultiplier tube (MAPMT). Incident photons Compton scatter in plastic scintillator elements and are subsequently absorbed in inorganic scintillator elements; a net polarization signal is revealed by a characteristic asymmetry in the azimuthal scattering angles. We have constructed a prototype GRAPE module containing a single CsI(Na) calorimeter element, at the center of the MAPMT, surrounded by 60 plastic elements. The prototype has been combined with custom readout electronics and software to create a complete 'engineering model' of the GRAPE instrument. This engineering model has been calibrated using a nearly 100% polarized hard X-ray beam at the Advanced Photon Source at Argonne National Laboratory. We find modulation factors of 0.46±0.06 and 0.48±0.03 at 69.5 and 129.5 keV, respectively, in good agreement with Monte Carlo simulations. In this paper we present details of the beam test, data analysis, and simulations, and discuss the implications of our results for the further development of the GRAPE concept.

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

    International Nuclear Information System (INIS)

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

    2015-01-01

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

  12. A FOCUSED, HARD X-RAY LOOK AT ARP 299 WITH NuSTAR

    Energy Technology Data Exchange (ETDEWEB)

    Ptak, A.; Hornschemeier, A.; Lehmer, B.; Yukita, M.; Wik, D.; Tatum, M. [NASA Goddard Space Flight Center, Code 662, Greenbelt, MD 20771 (United States); Zezas, A. [Department of Physics, University of Crete, Herakleion (Greece); Antoniou, V. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Argo, M. K. [Jodrell Bank Centre for Astrophysics, The University of Manchester, Oxford Road, Manchester M13 9PL (United Kingdom); Ballo, L.; Della Ceca, R. [Osservatorio Astronomico di Brera (INAF), via Brera 28, I-20121 Milano (Italy); Bechtol, K. [Kavli Institute for Cosmological Physics, Chicago, IL 60637 (United States); Boggs, S.; Craig, W. W.; Krivonos, R. [U.C. Berkeley Space Sciences Laboratory, Berkeley, CA (United States); Christensen, F. E. [National Space Institute, Technical University of Denmark, DK-2100 Copenhagen (Denmark); Hailey, C. J. [Columbia University, New York, NY (United States); Harrison, F. A. [Caltech Division of Physics, Mathematics and Astronomy, Pasadena, CA (United States); Maccarone, T. J. [Department of Physics, Texas Tech University, Lubbock, TX 79409 (United States); Stern, D. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); and others

    2015-02-20

    We report on simultaneous observations of the local starburst system Arp 299 with NuSTAR and Chandra, which provides the first resolved images of this galaxy up to energies of ∼45 keV. Fitting the 3-40 keV spectrum reveals a column density of N {sub H} ∼ 4 × 10{sup 24} cm{sup –2}, characteristic of a Compton-thick active galactic nucleus (AGN), and a 10-30 keV luminosity of 1.2 × 10{sup 43} erg s{sup –1}. The hard X-rays detected by NuSTAR above 10 keV are centered on the western nucleus, Arp 299-B, which previous X-ray observations have shown to be the primary source of neutral Fe-K emission. Other X-ray sources, including Arp 299-A, the eastern nucleus also thought to harbor an AGN, as well as X-ray binaries, contribute ≲ 10% to the 10-20 keV emission from the Arp 299 system. The lack of significant emission above 10 keV other than that attributed to Arp 299-B suggests that: (1) any AGN in Arp 299-A must be heavily obscured (N {sub H} > 10{sup 24} cm{sup –2}) or have a much lower luminosity than Arp 299-B and (2) the extranuclear X-ray binaries have spectra that cut-off above ∼10 keV. Such soft spectra are characteristic of ultraluminous X-ray sources observed to date by NuSTAR.

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

    DEFF Research Database (Denmark)

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

    2013-01-01

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

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

    Science.gov (United States)

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

    2017-11-01

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

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

    International Nuclear Information System (INIS)

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

    2007-01-01

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

  16. A MODEL FOR THE CORRELATION OF HARD X-RAY INDEX WITH EDDINGTON RATIO IN BLACK HOLE X-RAY BINARIES

    International Nuclear Information System (INIS)

    Qiao, Erlin; Liu, B. F.

    2013-01-01

    Observations show that there is a positive correlation between the Eddington ratio λ and hard X-ray index Γ for λ ∼> 0.01, and there is an anti-correlation between λ and Γ for λ ∼ bol /L Edd ). In this work, we theoretically investigate the correlation between Γ and λ within the framework of a disk-corona model. We improve the model by taking into account all cooling processes, including synchrotron and self-Compton radiations in the corona, Comptonization of the soft photons from the underlying accretion disk, and the bremsstrahlung radiations. Presuming that the coronal flow above the disk can reach up to the 0.1 Eddington rate at the outer region, we calculate the structure of the two-phase accretion flows and the emergent spectra for accretion rates from 0.003 to 0.1. We find that at accretion rates larger than bsim0.01 Eddington rate, a fraction of coronal gas condenses into the disk and an inner disk can be sustained by condensation. In this case, the X-ray emission is dominated by the scattering of the soft photon from the underlying disk in the corona. The emission from the inner disk and corona can produce the positive correlation between λ and Γ. While at accretion rates lower than bsim0.01 Eddington accretion rate, the inner disk vanishes completely by evaporation, and the accretion is dominated by advection-dominated accretion flows (ADAFs), in which the X-ray emission is produced by the Comptonization of the synchrotron and bremsstrahlung photons of ADAF itself. The emission from ADAFs can produce the anti-correlation between λ and Γ. We show that our model can roughly explain the observed evolution of Γ 3-25keV with L 0.5-25keV /L Edd for the black hole X-ray transient H1743–322 in the decay of 2003 from the thermal-dominated state to low/hard state.

  17. INTEGRAL hard X-ray spectra of the cosmic X-ray background and Galactic ridge emission

    Science.gov (United States)

    Türler, M.; Chernyakova, M.; Courvoisier, T. J.-L.; Lubiński, P.; Neronov, A.; Produit, N.; Walter, R.

    2010-03-01

    Aims: We derive the spectra of the cosmic X-ray background (CXB) and of the Galactic ridge X-ray emission (GRXE) in the ~20-200 keV range from the data of the IBIS instrument aboard the INTEGRAL satellite obtained during the four dedicated Earth-occultation observations in early 2006. Methods: We analyze the modulation of the IBIS/ISGRI detector counts induced by the passage of the Earth through the field of view of the instrument. Unlike previous studies, we do not fix the spectral shape of the various contributions, but model instead their spatial distribution and derive for each of them the expected modulation of the detector counts. The spectra of the diffuse emission components are obtained by fitting the normalizations of the model lightcurves to the observed modulation in different energy bins. Because of degeneracy, we guide the fits with a realistic choice of the input parameters and a constraint for spectral smoothness. Results: The obtained CXB spectrum is consistent with the historic HEAO-1 results and falls slightly below the spectrum derived with Swift/BAT. A 10% higher normalization of the CXB cannot be completely excluded, but it would imply an unrealistically high albedo of the Earth. The derived spectrum of the GRXE confirms the presence of a minimum around 80 keV with improved statistics and yields an estimate of ~0.6 M⊙ for the average mass of white dwarfs in the Galaxy. The analysis also provides updated normalizations for the spectra of the Earth's albedo and the cosmic-ray induced atmospheric emission. Conclusions: This study demonstrates the potential of INTEGRAL Earth-occultation observations to derive the hard X-ray spectra of three fundamental components: the CXB, the GRXE and the Earth emission. Further observations would be extremely valuable to confirm our results with improved statistics.

  18. Watching proteins function with time-resolved x-ray crystallography

    Energy Technology Data Exchange (ETDEWEB)

    Šrajer, Vukica; Schmidt, Marius

    2017-08-22

    Macromolecular crystallography was immensely successful in the last two decades. To a large degree this success resulted from use of powerful third generation synchrotron x-ray sources. An expansive database of more than 100 000 protein structures, of which many were determined at resolution better than 2 Å, is available today. With this achievement, the spotlight in structural biology is shifting from determination of static structures to elucidating dynamic aspects of protein function. A powerful tool for addressing these aspects is time-resolved crystallography, where a genuine biological function is triggered in the crystal with a goal of capturing molecules in action and determining protein kinetics and structures of intermediates (Schmidt et al 2005a Methods Mol. Biol. 305 115–54, Schmidt 2008 Ultrashort Laser Pulses in Biology and Medicine (Berlin: Springer) pp 201–41, Neutze and Moffat 2012 Curr. Opin. Struct. Biol. 22 651–9, Šrajer 2014 The Future of Dynamic Structural Science (Berlin: Springer) pp 237–51). In this approach, short and intense x-ray pulses are used to probe intermediates in real time and at room temperature, in an ongoing reaction that is initiated synchronously and rapidly in the crystal. Time-resolved macromolecular crystallography with 100 ps time resolution at synchrotron x-ray sources is in its mature phase today, particularly for studies of reversible, light-initiated reactions. The advent of the new free electron lasers for hard x-rays (XFELs; 5–20 keV), which provide exceptionally intense, femtosecond x-ray pulses, marks a new frontier for time-resolved crystallography. The exploration of ultra-fast events becomes possible in high-resolution structural detail, on sub-picosecond time scales (Tenboer et al 2014 Science 346 1242–6, Barends et al 2015 Science 350 445–50, Pande et al 2016 Science 352 725–9). We review here state-of-the-art time-resolved crystallographic experiments both at synchrotrons and XFELs. We

  19. Watching proteins function with time-resolved x-ray crystallography

    International Nuclear Information System (INIS)

    Šrajer, Vukica; Schmidt, Marius

    2017-01-01

    Macromolecular crystallography was immensely successful in the last two decades. To a large degree this success resulted from use of powerful third generation synchrotron x-ray sources. An expansive database of more than 100 000 protein structures, of which many were determined at resolution better than 2 Å, is available today. With this achievement, the spotlight in structural biology is shifting from determination of static structures to elucidating dynamic aspects of protein function. A powerful tool for addressing these aspects is time-resolved crystallography, where a genuine biological function is triggered in the crystal with a goal of capturing molecules in action and determining protein kinetics and structures of intermediates (Schmidt et al 2005a Methods Mol. Biol . 305 115–54, Schmidt 2008 Ultrashort Laser Pulses in Biology and Medicine (Berlin: Springer) pp 201–41, Neutze and Moffat 2012 Curr. Opin. Struct. Biol . 22 651–9, Šrajer 2014 The Future of Dynamic Structural Science (Berlin: Springer) pp 237–51). In this approach, short and intense x-ray pulses are used to probe intermediates in real time and at room temperature, in an ongoing reaction that is initiated synchronously and rapidly in the crystal. Time-resolved macromolecular crystallography with 100 ps time resolution at synchrotron x-ray sources is in its mature phase today, particularly for studies of reversible, light-initiated reactions. The advent of the new free electron lasers for hard x-rays (XFELs; 5–20 keV), which provide exceptionally intense, femtosecond x-ray pulses, marks a new frontier for time-resolved crystallography. The exploration of ultra-fast events becomes possible in high-resolution structural detail, on sub-picosecond time scales (Tenboer et al 2014 Science 346 1242–6, Barends et al 2015 Science 350 445–50, Pande et al 2016 Science 352 725–9). We review here state-of-the-art time-resolved crystallographic experiments both at synchrotrons and XFELs

  20. 44Ti Nucleosynthesis Lines and Hard X-ray Continuum in Young SNRs: from INTEGRAL to Simbol-X

    Science.gov (United States)

    Renaud, M.; Terrier, R.; Trap, G.; Lebrun, F.; Decourchelle, A.; Vink, J.

    2009-05-01

    Supemovae and their remnants are the main Galactic nucleosynthesis sites and the privileged sources of Galactic cosmic rays. The youngest of such remnants can be studied through two distinct observational features: 44Ti γ-ray lines and the hard X-ray nonthermal continuum emission. The former gives unique information on the nucleosynthesis conditions occuring during the first stages of the explosion, while the latter provides clues on acceleration processes at supernova remnant shocks. In this contribution, we present new INTEGRAL results on Tycho, the remnant of a historical supernova, and on G1.9+0.3, which has been recently unveiled as the youngest Galactic supernova remnant. Expectations with Simbol-X are also addressed.

  1. 44Ti Nucleosynthesis Lines and Hard X-ray Continuum in Young SNRs: from INTEGRAL to Simbol-X

    International Nuclear Information System (INIS)

    Renaud, M.; Terrier, R.; Lebrun, F.; Trap, G.; Decourchelle, A.; Vink, J.

    2009-01-01

    Supemovae and their remnants are the main Galactic nucleosynthesis sites and the privileged sources of Galactic cosmic rays. The youngest of such remnants can be studied through two distinct observational features: 44 Tiγ-ray lines and the hard X-ray nonthermal continuum emission. The former gives unique information on the nucleosynthesis conditions occuring during the first stages of the explosion, while the latter provides clues on acceleration processes at supernova remnant shocks. In this contribution, we present new INTEGRAL results on Tycho, the remnant of a historical supernova, and on G1.9+0.3, which has been recently unveiled as the youngest Galactic supernova remnant. Expectations with Simbol-X are also addressed.

  2. Time-resolved suprathermal x-rays

    International Nuclear Information System (INIS)

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

    1978-01-01

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

  3. Micro Hard-X Ray Camera: From Caliste 64 to Caliste 256

    International Nuclear Information System (INIS)

    Meuris, A.; Limousin, O.; Le Mer, I.; Pinsard, F.; Blondel, C.; Daly, F.; Lugiez, F.; Gevin, O.; Delagnes, E.; Chavassieux, M.; Vassal, M.C.; Bocage, R.; Soufflet, F.

    2009-01-01

    Caliste project aims at hybridizing 1 cm 2 Cd(Zn)Te detectors with low noise front-end electronics, in a single component standing in a 1 * 1 * 2 cm 3 volume. The micro-camera is a spectroscopic imager for X and gamma rays detection, with time-tagging capability. Hybridization consists in stacking full custom ASICs perpendicular to the detection surface. The first prototype Caliste 64 integrates a detector of 8 * 8 pixels of 1 mm pitch. Fabrication and characterizations of nine cameras units validate the design and the hybridization concept. Spectroscopic tests result in a mean energy resolution of ∼0.7 keV FWHM at 14 keV and ∼0.85 keV FWHM at 60 keV using 1 mm-thick Al Schottky CdTe detectors biased at -400 V and cooled down to 15 degrees C. The new prototype called Caliste 256 integrates 16 * 16 pixels of 580 m pitch in the same volume as Caliste 64. Electrical tests with the first sample fabricated without detector result in a mean equivalent noise charge of 64e - rms (9.6 μs, no leakage current). Caliste devices are 4-side buttable and can be used as elementary detection units of a large hard X-ray focal plane, as for the 64 cm 2 high energy detector of the Simbol-X astronomical space mission. (authors)

  4. HARD X-RAY ASYMMETRY LIMITS IN SOLAR FLARE CONJUGATE FOOTPOINTS

    Energy Technology Data Exchange (ETDEWEB)

    Daou, Antoun G.; Alexander, David, E-mail: agdaou@rice.edu, E-mail: dalex@rice.edu [Department of Physics and Astronomy, Rice University, 6100 Main Street, MS 108, Houston, TX, 77005 (United States)

    2016-11-20

    The transport of energetic electrons in a solar flare is modeled using a time-dependent one-dimensional Fokker–Planck code that incorporates asymmetric magnetic convergence. We derive the temporal and spectral evolution of the resulting hard X-ray (HXR) emission in the conjugate chromospheric footpoints, assuming thick target photon production, and characterize the time evolution of the numerically simulated footpoint asymmetry and its relationship to the photospheric magnetic configuration. The thick target HXR asymmetry in the conjugate footpoints is found to increase with magnetic field ratio as expected. However, we find that the footpoint HXR asymmetry saturates for conjugate footpoint magnetic field ratios ≥4. This result is borne out in a direct comparison with observations of 44 double-footpoint flares. The presence of such a limit has not been reported before, and may serve as both a theoretical and observational benchmark for testing a range of particle transport and flare morphology constraints, particularly as a means to differentiate between isotropic and anisotropic particle injection.

  5. Hard X-ray synchrotron light source for industrial and materials research applications

    International Nuclear Information System (INIS)

    Lehr, H.; Ehrfeld, W.; Moser, H.O.; Schmidt, M.; Herminghaus, H.

    1992-01-01

    The requirements for industrial production or for an industry-related analytical environment is demonstrated for the case of the proposed hard X-ray synchrotron light source. The source is intended to provide radiation mainly for deep X-ray lithography as part of the LIGA-process in microfabrication, and for analytical and diagnostic purposes in materials research and microtechnology. It offers up to 48 bending magnet beamlines with a characteristic wavelength of 2 A. An electron energy of 2.5 GeV and normal conducting magnets will be used. A FODO lattice with a beam emittance of 3x10 -7 m rad and four dispersion-free straight sections to accommodate insertion devices, injection elements and RF structures has been designed. (R.P.) 5 refs.; 4 figs.; 1 tab

  6. Accretion Properties of a Sample of Hard X-Ray (<60 keV) Selected Seyfert 1 Galaxies

    Science.gov (United States)

    Wang, J.; Mao, Y. F.; Wei, J. Y.

    2009-02-01

    We examine the accretion properties in a sample of 42 hard (3-60 keV) X-ray selected nearby broad-line active galactic nuclei (AGNs). The energy range in the sample is harder than that usually used in similar previous studies. These AGNs are mainly complied from the RXTE All Sky Survey, and complemented by the released INTEGRAL AGN catalog. The black hole masses, bolometric luminosities of AGN, and Eddington ratios are derived from their optical spectra in terms of the broad Hβ emission line. The tight correlation between the hard X-ray (3-20 keV) and bolometric/line luminosity is well identified in our sample. Also identified is a strong inverse Baldwin relationship of the Hβ emission line. In addition, all of these hard X-ray AGNs are biased toward luminous objects with a high Eddington ratio (mostly between 0.01 and 0.1) and a low column density (Simbol-X, and NeXT. Finally, the correlation between RFe (= optical Fe II/Hβ) and disk temperature as assessed by T vprop (L/L Edd)M -1 BH leads us to suggest that the strength of the Fe II emission is mainly determined by the shape of the ionizing spectrum.

  7. High-spatial resolution and high-spectral resolution detector for use in the measurement of solar flare hard x rays

    International Nuclear Information System (INIS)

    Desai, U.D.; Orwig, L.E.

    1988-01-01

    In the areas of high spatial resolution, the evaluation of a hard X-ray detector with 65 micron spatial resolution for operation in the energy range from 30 to 400 keV is proposed. The basic detector is a thick large-area scintillator faceplate, composed of a matrix of high-density scintillating glass fibers, attached to a proximity type image intensifier tube with a resistive-anode digital readout system. Such a detector, combined with a coded-aperture mask, would be ideal for use as a modest-sized hard X-ray imaging instrument up to X-ray energies as high as several hundred keV. As an integral part of this study it was also proposed that several techniques be critically evaluated for X-ray image coding which could be used with this detector. In the area of high spectral resolution, it is proposed to evaluate two different types of detectors for use as X-ray spectrometers for solar flares: planar silicon detectors and high-purity germanium detectors (HPGe). Instruments utilizing these high-spatial-resolution detectors for hard X-ray imaging measurements from 30 to 400 keV and high-spectral-resolution detectors for measurements over a similar energy range would be ideally suited for making crucial solar flare observations during the upcoming maximum in the solar cycle

  8. Status of the Nanoscopium Scanning Hard X-ray Nanoprobe Beamline of Synchrotron Soleil

    Science.gov (United States)

    Somogyi, A.; Kewish, C. M.; Ribbens, M.; Moreno, T.; Polack, F.; Baranton, G.; Desjardins, K.; Samama, J. P.

    2013-10-01

    The Nanoscopium 155 m-long scanning hard X-ray nanoprobe beamline of Synchrotron Soleil (St Aubin, France) is dedicated to quantitative multi-modal 2D/3D imaging. The beamline aims to reach down to 30 nm spatial resolution in the 5-20 keV energy range. Two experimental stations working in consecutive operation mode will be dedicated to coherent diffractive imaging and scanning X-ray nanoprobe techniques. The beamline is in the construction phase, the first user experiments are expected in 2014. The main characteristics of the beamline and an overview of its status are given in this paper.

  9. Status of the Nanoscopium Scanning Hard X-ray Nanoprobe Beamline of Synchrotron Soleil

    International Nuclear Information System (INIS)

    Somogyi, A; Kewish, C M; Ribbens, M; Moreno, T; Polack, F; Baranton, G; Desjardins, K; Samama, J P

    2013-01-01

    The Nanoscopium 155 m-long scanning hard X-ray nanoprobe beamline of Synchrotron Soleil (St Aubin, France) is dedicated to quantitative multi-modal 2D/3D imaging. The beamline aims to reach down to 30 nm spatial resolution in the 5–20 keV energy range. Two experimental stations working in consecutive operation mode will be dedicated to coherent diffractive imaging and scanning X-ray nanoprobe techniques. The beamline is in the construction phase, the first user experiments are expected in 2014. The main characteristics of the beamline and an overview of its status are given in this paper

  10. First hard X-ray detection of the non-thermal emission around the Arches cluster: morphology and spectral studies with NuSTAR

    DEFF Research Database (Denmark)

    Krivonos, Roman A.; Tomsick, John A.; Bauer, Franz E.

    2014-01-01

    The Arches cluster is a young, densely packed massive star cluster in our Galaxy that shows a high level of star formation activity. The nature of the extended non-thermal X-ray emission around the cluster remains unclear. The observed bright Fe Ku line emission at 6.4 keV from material that is n......The Arches cluster is a young, densely packed massive star cluster in our Galaxy that shows a high level of star formation activity. The nature of the extended non-thermal X-ray emission around the cluster remains unclear. The observed bright Fe Ku line emission at 6.4 keV from material...... and spectrum. The spatial distribution of the hard X-ray emission is found to be consistent with the broad region around the cluster where the 6.4 keV line is observed. The interpretation of the hard X-ray emission within the context of the X-ray reflection model puts a strong constraint on the luminosity...... of the possible illuminating hard X-ray source. The properties of the observed emission are also in broad agreement with the low-energy cosmic-ray proton excitation scenario....

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

    Directory of Open Access Journals (Sweden)

    Bachetti Matteo

    2014-01-01

    Full Text Available The NuSTAR hard X-ray telescope observed the transient Be/X-ray binary GS 0834–430 during its 2012 outburst. The source is detected between 3 – 79 keV with high statistical significance, and we were able to perform very accurate spectral and timing analysis. The phase-averaged spectrum is consistent with that observed in many other magnetized accreting pulsars. We fail to detect cyclotron resonance scattering features in either phase-averaged nor phase-resolved spectra that would allow us to constrain the pulsar’s magnetic field. We detect a pulse period of ~ 12:29 s in all energy bands. The pulse profile can be modeled with a double Gaussian and shows a strong and smooth hard lag of up to 0.3 cycles in phase, or about 4s between the pulse at ~ 3 and ≳ 30 keV. This is the first report of such a strong lag in high-mass X-ray binary (HMXB pulsars. Previously reported lags have been significantly smaller in phase and restricted to low-energies (E<10 keV. We investigate the possible mechanisms that might produce such lags. We find the most likely explanation for this effect to be a complex beam geometry.

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

    Science.gov (United States)

    Rutherford, Michael E; Chapman, David J; White, Thomas G; Drakopoulos, Michael; Rack, Alexander; Eakins, Daniel E

    2016-05-01

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

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

    International Nuclear Information System (INIS)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    Southworth, S.; Gemmell, D.

    1996-08-01

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

  15. Cell survival studies using ultrasoft x rays

    International Nuclear Information System (INIS)

    Schillaci, M.E.; Raju, M.R.; Carpenter, S.; Cornforth, M.; Wilder, M.

    1987-01-01

    Cell survival was studied for V79 hamster, 10T1/2 mouse, and human skin fibroblast cell lines, using carbon K (0.28 keV), copper K (8.0 keV), and 250 kVp x rays. Because of the rapid attenuation of the carbon x rays, cellular dimensions at the time of exposure were measured using optical and electron microscopy, and frequency distributions of mean dose absorbed by the cell nucleus were obtained. The results indicate that the differences in cell killing between ultra-soft and hard x rays may depend on the nuclear thickness of the cells. Studies of the effects of hypoxia on V79 and 10T1/2 cells using carbon K, aluminum K (1.5 keV), and copper K x rays show decreasing OER values with decreasing x-ray energy and no difference between the two cell lines. Age response studies with V79 cells show similar cell-cycle variation of survival for carbon K and aluminum K x rays as for hard x rays

  16. Hard X-ray Microscopy with sub 30 nm Spatial Resolution

    International Nuclear Information System (INIS)

    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

    2007-01-01

    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

  17. X-ray Time Lags in TeV Blazars X. Chen1,∗ , G. Fossati1, E. Liang1 ...

    Indian Academy of Sciences (India)

    Abstract. We use Monte Carlo/Fokker–Planck simulations to study the. X-ray time lags. Our results show that soft lags will be observed as long as the decay of the flare is dominated by radiative cooling, even when acceleration and cooling time scales are similar. Hard lags can be pro- duced in the presence of a competitive ...

  18. A hard x-ray spectrometer for high angular resolution observations of cosmic sources

    International Nuclear Information System (INIS)

    Hailey, C.J.; Ziock, K.P.; Harrison, F.; Kahn, S.M.; Liedahl, D.; Lubin, P.M.; Seiffert, M.

    1988-01-01

    LAXRIS (large area x-ray imaging spectrometer) is an experimental, balloon-borne, hard x-ray telescope that consists of a coaligned array of x-ray imaging spectrometer modules capable of obtaining high angular resolution (1--3 arcminutes) with moderate energy resolution in the 20- to 300-keV region. Each spectrometer module consists of a CsI(Na) crystal coupled to a position-sensitive phototube with a crossed-wire, resistive readout. Imaging is provided by a coded aperture mask with a 4-m focal length. The high angular resolution is coupled with rather large area (/approximately/800 cm 2 ) to provide good sensitivity. Results are presented on performance and overall design. Sensitivity estimates are derived from a Monte-Carlo code developed to model the LAXRIS response to background encountered at balloon altitudes. We discuss a variety of observations made feasible by high angular resolution. For instance, spatially resolving the nonthermal x-ray emission from clusters of galaxies is suggested as an ideal program for LAXRIS. 15 refs., 5 figs

  19. Annealing induced atomic rearrangements on (Ga,In) (N,As) probed by hard X-ray photoelectron spectroscopy and X-ray absorption fine structure.

    Science.gov (United States)

    Ishikawa, Fumitaro; Higashi, Kotaro; Fuyuno, Satoshi; Morifuji, Masato; Kondow, Masahiko; Trampert, Achim

    2018-04-13

    We study the effects of annealing on (Ga 0.64 ,In 0.36 ) (N 0.045 ,As 0.955 ) using hard X-ray photoelectron spectroscopy and X-ray absorption fine structure measurements. We observed surface oxidation and termination of the N-As bond defects caused by the annealing process. Specifically, we observed a characteristic chemical shift towards lower binding energies in the photoelectron spectra related to In. This phenomenon appears to be caused by the atomic arrangement, which produces increased In-N bond configurations within the matrix, as indicated by the X-ray absorption fine structure measurements. The reduction in the binding energies of group-III In, which occurs concomitantly with the atomic rearrangements of the matrix, causes the differences in the electronic properties of the system before and after annealing.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-04-01

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

  1. Transition radiation in metal-metal multilayer nanostructures as a medical source of hard x-ray radiation

    International Nuclear Information System (INIS)

    Pokrovsky, A. L.; Kaplan, A. E.; Shkolnikov, P. L.

    2006-01-01

    We show that a periodic metal-metal multilayer nanostructure can serve as an efficient source of hard x-ray transition radiation. Our research effort is aimed at developing an x-ray source for medical applications, which is based on using low-energy relativistic electrons. The approach toward choosing radiator-spacer couples for the generation of hard x-ray resonant transition radiation by few-MeV electrons traversing solid multilayer structures for the energies of interest to medicine (30-50 keV) changes dramatically compared with that for soft x-ray radiation. We show that one of the main factors in achieving the required resonant line is the absence of the contrast of the refractive indices between the spacer and the radiator at the far wings of the radiation line; for that purpose, the optimal spacer, as a rule, should have a higher atomic number than the radiator. Having experimental goals in mind, we have considered also the unwanted effects due to bremsstrahlung radiation, absorption and scattering of radiated photons, detector-related issues, and inhibited coherence of transition radiation due to random deviation of spacing between the layers. Choosing as a model example a Mo-Ag radiator-spacer pair of materials, we demonstrate that the x-ray transition radiation line can be well resolved with the use of spatial and frequency filtering

  2. XMM-Newton Detection of Hard X-Ray Emission in the Nitrogen-Type Wolf-Rayet Star WR 110

    Science.gov (United States)

    Skinner, Stephen L.; Zhekov, Svetozar A.; Güdel, Manuel; Schmutz, Werner

    2002-06-01

    We have used the excellent sensitivity of XMM-Newton to obtain the first high-quality X-ray spectrum of a Wolf-Rayet (W-R) star that is not known to be a member of a binary system. Our target, the nitrogen-type star WR 110 (HD 165688), was also observed and detected with the Very Large Array at four different frequencies. The radio flux density increases with frequency according to a power law Sν~ν+0.64+/-0.10, in very good agreement with the behavior expected for free-free wind emission. The radio data give an ionized mass-loss rate M=4.9×10-5 Msolar yr-1 for an assumed spherical constant-velocity wind. The undispersed CCD X-ray spectra reveal strong emission lines from He-like ions of Mg, Si, and S. The emission measure distribution shows a dominant contribution from cool plasma with a characteristic temperature kTcool~0.5 keV (~6 MK). Little or no excess absorption of this cool component above the value expected from the visual extinction is present. We conclude that the bulk of the cool plasma detected by XMM-Newton lies at hundreds of stellar radii or more if the wind is approximately spherical and homogeneous, but it could lie closer to the star if the wind is clumped. If the cool plasma is due to instability-driven wind shocks, then typical shock velocities are vs~340-550 km s-1 and the average filling factor of X-ray-emitting gas in the wind is no larger than f~10-6. A surprising result is the unambiguous detection of a hard X-ray component that is clearly seen in the hard-band images and the spectra. This hard component accounts for about half of the observed flux and can be acceptably fitted by a hot, optically thin thermal plasma or a power-law model. If the emission is thermal, then a temperature kThot>=3 keV is derived. Such high temperatures are not predicted by current instability-driven wind shock models, and a different mechanism is thus required to explain the hard X-rays. We examine several possible mechanisms and show that the hard emission

  3. NuSTAR Search for Hard X-ray Emission from the Star Formation Regions in Sh2-104

    Science.gov (United States)

    Gotthelf, Eric V.

    2016-04-01

    We present NuSTAR hard X-ray observations of Sh2-104, a compact Hii region containing several young massive stellar clusters (YMSCs). We have detected distinct hard X-ray sources coincident with localized VERITAS TeV emission recently resolved from the giant gamma-ray complex MGRO J2019+37 in the Cygnus region. Faint, diffuse X-ray emission coincident with the eastern YMSC in Sh2-104 is likely the result of colliding winds of component stars. Just outside the radio shell of Sh2-104 lies 3XMM J201744.7+365045 and nearby nebula NuSTAR J201744.3+364812, whose properties are most consistent with extragalactic objects. The combined XMM-Newton and NuSTAR spectrum of 3XMM J201744.7+365045 is well-fit to an absorbed power-law model with NH = (3.1+/-1.0)E22 1/cm^2 and photon index Gamma = 2.1+/-0.1. Based on possible long-term flux variation and lack of detected pulsations (Sh2-104 will help identify the nature of the X-ray sources and their relation to MGRO J2019+37.

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

    Directory of Open Access Journals (Sweden)

    L. Miaja-Avila

    2015-03-01

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

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

    International Nuclear Information System (INIS)

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

    2014-01-01

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

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

    DEFF Research Database (Denmark)

    Jimenez-Garate, M.A.; Craig, W.W.; Hailey, C.J.

    2000-01-01

    We fabricated x-ray mirrors for hard x-ray (greater than or equal to 10 keV) telescopes using multilayer coatings and an improved epoxy-replicated aluminum foil (ERAF) nonvacuum technology. The ERAF optics have similar to1 arcmin axial figure half-power diameter (HPD) and passed environmental...... telescope HPD, we designed a figure metrology system and a new mounting technique. We describe a cylindrical metrology system built for fast axial and roundness figure measurement of hard x-ray conical optics. These developments lower cost and improve the optics performance of the HEFT (high-energy focusing...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-11-21

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

  8. Current status of the hard x-ray nanoprobe beamline at the SSRF

    Science.gov (United States)

    Li, Aiguo; Jiang, Hui; Wang, Hua; Zhang, Zhaohong; He, Yan; Zhao, Gaofeng; Shu, Deming

    2017-09-01

    The hard X-ray nanoprobe beamline (HXN) designed at the Shanghai Synchrotron Radiation facility (SSRF) will be of capability to realize a focal spot size of 10 nm for hard X-rays to satisfy requirements in biology, environmental, material sciences and etc.. The beamline includes two modes of operation, high energy resolution mode and high flux mode respectively. High flux mode utilizes the multilayer KB system to obtain high-flux diffraction-limited focusing of 10nm. An ultra-high-precision figure fabrication for diffraction-limited focusing is required to meet the Rayleigh Criterion. An idea to overcome this problem is to introduce a phase compensator upstream of the KB system to compensate the wavefront errors in the beamline. At wavelength speckle-based method will be used to measure the wavefront error in the beamline and feedback to the phase compensator. Vibration measurements have been carried out at the secondary source and endstation hutch. The flexure hinge mechanisms and high-precision actuators ensure the KB system and sample manipulator working with high stability. The building of HXN has been designed and is under construction at present.

  9. Polarization and spectral features of the hard x-ray continuum from non-thermal plasmas

    International Nuclear Information System (INIS)

    Hesse, M.; Platz, P.

    1989-12-01

    Starting from the cross-sections for the free-free radiation obtained within the relativistic Born-Elwert theory, we calculate the spectral and polarization properties of the hard X-ray continuum (hν > 50 KeV) for plasmas containing fast electrons with an anisotropic velocity distribution. The physical and geometrical quantities of our model are oriented towards the future lower-hybrid current drive (LHCD) experiments on Tore-Supra. Our parameter space covers parallel and perpendicular temperatures, the nuclear charge of the ions (mainly Z = 14 and 28), the cut-off energy of the electrons, the radial current profile and the viewing angle. Extensive calculations open on the optimum conditions for polarization measurements and also give guide-lines for the quantitative interpretation of data under real plasma conditions. A second part of this report will treat with the operational principles and expected performances of hard X-ray polarimeters

  10. Development of a hard x-ray focal plane compton polarimeter: a compact polarimetric configuration with scintillators and Si photomultipliers

    Science.gov (United States)

    Chattopadhyay, T.; Vadawale, S. V.; Goyal, S. K.; Mithun, N. P. S.; Patel, A. R.; Shukla, R.; Ladiya, T.; Shanmugam, M.; Patel, V. R.; Ubale, G. P.

    2016-02-01

    X-ray polarization measurement of cosmic sources provides two unique parameters namely degree and angle of polarization which can probe the emission mechanism and geometry at close vicinity of the compact objects. Specifically, the hard X-ray polarimetry is more rewarding because the sources are expected to be intrinsically highly polarized at higher energies. With the successful implementation of Hard X-ray optics in NuSTAR, it is now feasible to conceive Compton polarimeters as focal plane detectors. Such a configuration is likely to provide sensitive polarization measurements in hard X-rays with a broad energy band. We are developing a focal plane hard X-ray Compton polarimeter consisting of a plastic scintillator as active scatterer surrounded by a cylindrical array of CsI(Tl) scintillators. The scatterer is 5 mm diameter and 100 mm long plastic scintillator (BC404) viewed by normal PMT. The photons scattered by the plastic scatterer are collected by a cylindrical array of 16 CsI(Tl) scintillators (5 mm × 5 mm × 150 mm) which are read by Si Photomultiplier (SiPM). Use of the new generation SiPMs ensures the compactness of the instrument which is essential for the design of focal plane detectors. The expected sensitivity of such polarimetric configuration and complete characterization of the plastic scatterer, specially at lower energies have been discussed in [11, 13]. In this paper, we characterize the CsI(Tl) absorbers coupled to SiPM. We also present the experimental results from the fully assembled configuration of the Compton polarimeter.

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

    Science.gov (United States)

    Mushotzky, Richard

    2009-01-01

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

  12. Time-resolved x-ray absorption spectroscopy: Watching atoms dance

    Science.gov (United States)

    Milne, Chris J.; Pham, Van-Thai; Gawelda, Wojciech; van der Veen, Renske M.; El Nahhas, Amal; Johnson, Steven L.; Beaud, Paul; Ingold, Gerhard; Lima, Frederico; Vithanage, Dimali A.; Benfatto, Maurizio; Grolimund, Daniel; Borca, Camelia; Kaiser, Maik; Hauser, Andreas; Abela, Rafael; Bressler, Christian; Chergui, Majed

    2009-11-01

    The introduction of pump-probe techniques to the field of x-ray absorption spectroscopy (XAS) has allowed the monitoring of both structural and electronic dynamics of disordered systems in the condensed phase with unprecedented accuracy, both in time and in space. We present results on the electronically excited high-spin state structure of an Fe(II) molecular species, [FeII(bpy)3]2+, in aqueous solution, resolving the Fe-N bond distance elongation as 0.2 Å. In addition an analysis technique using the reduced χ2 goodness of fit between FEFF EXAFS simulations and the experimental transient absorption signal in energy space has been successfully tested as a function of excited state population and chemical shift, demonstrating its applicability in situations where the fractional excited state population cannot be determined through other measurements. Finally by using a novel ultrafast hard x-ray 'slicing' source the question of how the molecule relaxes after optical excitation has been successfully resolved using femtosecond XANES.

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

    Science.gov (United States)

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

    2017-12-01

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

  14. Multi-time-scale X-ray reverberation mapping of accreting black holes

    Science.gov (United States)

    Mastroserio, Guglielmo; Ingram, Adam; van der Klis, Michiel

    2018-04-01

    Accreting black holes show characteristic reflection features in their X-ray spectrum, including an iron Kα line, resulting from hard X-ray continuum photons illuminating the accretion disc. The reverberation lag resulting from the path-length difference between direct and reflected emission provides a powerful tool to probe the innermost regions around both stellar-mass and supermassive black holes. Here, we present for the first time a reverberation mapping formalism that enables modelling of energy-dependent time lags and variability amplitude for a wide range of variability time-scales, taking the complete information of the cross-spectrum into account. We use a pivoting power-law model to account for the spectral variability of the continuum that dominates over the reverberation lags for longer time-scale variability. We use an analytic approximation to self-consistently account for the non-linear effects caused by this continuum spectral variability, which have been ignored by all previous reverberation studies. We find that ignoring these non-linear effects can bias measurements of the reverberation lags, particularly at low frequencies. Since our model is analytic, we are able to fit simultaneously for a wide range of Fourier frequencies without prohibitive computational expense. We also introduce a formalism of fitting to real and imaginary parts of our cross-spectrum statistic, which naturally avoids some mistakes/inaccuracies previously common in the literature. We perform proof-of-principle fits to Rossi X-ray Timing Explorer data of Cygnus X-1.

  15. Rossi X-Ray Timing Explorer Observation of PSR B0656+14

    International Nuclear Information System (INIS)

    Chang, H.; Ho, C.

    1999-01-01

    PSR B0656+14 was observed by the Rossi X-Ray Timing Explorer (RXTE) with the proportional counter array (PCA) and the high-energy X-ray timing experiment (HEXTE) for 160 ks during 1997 August 22 - September 3. No pulsation was firmly found in the timing analysis, during which the contemporaneous radio ephemeris and various statistical tests were applied in searching for evidence of pulsation. A marginal detection of pulsation at a confidence level of 95.5% based on the H test was found with data in the whole HEXTE energy band. In the energy band of 2-10 keV the RXTE PCA upper limits are about 1 order of magnitude lower than that from ASCA GIS data. If the Compton Gamma Ray Observatory EGRET detection of this pulsar is real, considering the common trait that most EGRET-detected pulsars have a cooling spectrum in hard X-ray and gamma-ray energy bands, the estimated RXTE upper limits indicate a deviation (low-energy turnover) from a cooling spectrum starting from 20 keV or higher. This in turn suggests an outer magnetospheric synchrotron radiation origin for high-energy emissions from PSR B0656+14. The RXTE PCA upper limits also suggest that a reported power-law component based on ASCA SIS data in 1-10 keV fitted jointly with ROSAT data, if real, should be mainly unpulsed. copyright copyright 1999. The American Astronomical Society

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

    Science.gov (United States)

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

    2017-06-01

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

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

    International Nuclear Information System (INIS)

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

    2017-01-01

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

  18. An XMM-Newton study of the hard X-ray sky

    Science.gov (United States)

    Piconcelli, E.; Cappi, M.; Bassani, L.; Di Cocco, G.; Dadina, M.

    2003-12-01

    We report on the spectral properties of a sample of 90 hard X-ray selected serendipitous sources detected in 12 XMM-Newton observations with 1 law modified by Galactic absorption offers an acceptable fit to ~ 65% of the source spectra. This fit yields an average photon index of ≈ 1.55 over the whole sample. We also find that the mean slope of the QSOs in our sample turns out to remain nearly constant ( (≈ 1.8-1.9) between 0 1022 cm-2) is ~ 30%, with little evolution in the range 2 <≈ F2-10˜< 80 x 10-14 erg cm-2 s-1. Interestingly, this value is a factor ~ 2 lower than predicted by the synthesis models of the CXB. This finding, detected for the first time in this survey, therefore suggests that most of the heavily obscured objects which make up the bulk of the CXB will be found at lower fluxes (F2-10< 10-14 erg cm-2 s-1). This mismatch together with other recent observational evidences which contrast with CXB model predictions suggest that one (or more) of the assumptions usually included in these models need to be revised.

  19. HARD X-RAY EMISSION DURING FLARES AND PHOTOSPHERIC FIELD CHANGES

    International Nuclear Information System (INIS)

    Burtseva, O.; Petrie, G. J. D.; Pevtsov, A. A.; Martínez-Oliveros, J. C.

    2015-01-01

    We study the correlation between abrupt permanent changes of magnetic field during X-class flares observed by the Global Oscillation Network Group and Helioseismic and Magnetic Imager instruments, and the hard X-ray (HXR) emission observed by RHESSI, to relate the photospheric field changes to the coronal restructuring and investigate the origin of the field changes. We find that spatially the early RHESSI emission corresponds well to locations of the strong field changes. The field changes occur predominantly in the regions of strong magnetic field near the polarity inversion line (PIL). The later RHESSI emission does not correspond to significant field changes as the flare footpoints are moving away from the PIL. Most of the field changes start before or around the start time of the detectable HXR signal, and they end at about the same time or later than the detectable HXR flare emission. Some of the field changes propagate with speed close to that of the HXR footpoint at a later phase of the flare. The propagation of the field changes often takes place after the strongest peak in the HXR signal when the footpoints start moving away from the PIL, i.e., the field changes follow the same trajectory as the HXR footpoint, but at an earlier time. Thus, the field changes and HXR emission are spatio-temporally related but not co-spatial nor simultaneous. We also find that in the strongest X-class flares the amplitudes of the field changes peak a few minutes earlier than the peak of the HXR signal. We briefly discuss this observed time delay in terms of the formation of current sheets during eruptions

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

    Science.gov (United States)

    Ueda, Yoshihiro

    2015-01-01

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

  1. An x-ray detector for time-resolved studies

    International Nuclear Information System (INIS)

    Rodricks, B.; Brizard, C.; Clarke, R.; Lowe, W.

    1992-01-01

    The development of ultrahigh-brightness x-ray sources makes time-resolved x-ray studies more and more feasible. Improvements in x-ray optics components are also critical for obtaining the appropriate beam for a particular type of experiment. Moreover, fast parallel detectors will be essential in order to exploit the combination of high intensity x-ray sources and novel optics for time-resolved experiments. A CCD detector with a time resolution of microseconds has been developed at the Advanced Photon Source (APS). This detector is fully programmable using CAMAC electronics and a Micro Vax computer. The techniques of time-resolved x-ray studies, which include scattering, microradiography, microtomography, stroboscopy, etc., can be applied to a range of phenomena (including rapid thermal annealing, surface ordering, crystallization, and the kinetics of phase transition) in order to understand these time-dependent microscopic processes. Some of these applications will be illustrated by recent results performed at synchrotrons. New powerful x-ray sources now under construction offer the opportunity to apply innovative approaches in time-resolved work

  2. Development of real-time x-ray microtomography system

    International Nuclear Information System (INIS)

    Takano, H; Morikawa, M; Konishi, S; Azuma, H; Shimomura, S; Tsusaka, Y; Kagoshima, Y; Nakano, S; Kosaka, N; Yamamoto, K

    2013-01-01

    We have developed a four-dimensional (4D) x-ray microcomputed tomography (CT) system that can obtain time-lapse CT volumes in real time. The system consists of a high-speed sample rotation system and a high-frame-rate x-ray imager, which are installed at a synchrotron radiation x-ray beamline. As a result of system optimization and introduction of a 'zoom resolution' procedure, a real-time 4D CT movie with a frame rate of 30 was obtained with a voxel size of 2.5 μm using 10 keV x-rays

  3. Hard X-ray emission spectroscopy with pink beam

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-06-01

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

  4. A study of the cross-correlation and time lag in black hole X-ray binary XTE J1859+226

    Science.gov (United States)

    Pei, Songpeng; Ding, Guoqiang; Li, Zhibing; Lei, Yajuan; Yuen, Rai; Qu, Jinlu

    2017-07-01

    With Rossi X-ray Timing Explorer (RXTE) data, we systematically study the cross-correlation and time lag in all spectral states of black hole X-ray binary (BHXB) XTE J1859+226 in detail during its entire 1999-2000 outburst that lasted for 166 days. Anti-correlations and positive correlations and their respective soft and hard X-ray lags are only detected in the first 100 days of the outburst when the luminosity is high. This suggests that the cross-correlations may be related to high luminosity. Positive correlations are detected in every state of XTE J1859+226, viz., hard state, hard-intermediate state (HIMS), soft-intermediate state (SIMS) and soft state. However, anti-correlations are only detected in HIMS and SIMS, anti-correlated hard lags are only detected in SIMS, while anti-correlated soft lags are detected in both HIMS and SIMS. Moreover, the ratio of the observations with anti-correlated soft lags to hard lags detected in XTE J1859+226 is significantly different from that in neutron star low-mass X-ray binaries (NS LMXBs). So far, anti-correlations are never detected in the soft state of BHXBs but detected in every branch or state of NS LMXBs. This may be due to the origin of soft seed photons in BHXBs is confined to the accretion disk and, for NS LMXBs, from both accretion disk and the surface of the NS. We notice that the timescale of anti-correlated time lags detected in XTE J1859+226 is similar with that of other BHXBs and NS LMXBs. We suggest that anti-correlated soft lag detected in BHXB may result from fluctuation in the accretion disk as well as NS LMXB.

  5. Design and performance of a one square meter proportional counter system for hard X-ray astronomy

    International Nuclear Information System (INIS)

    Bazzano, A.; Boccaccini, L.; La Padula, C.D.; Mastropietro, M.; Patriarca, R.; Polcaro, F.; Ubertini, P.

    1983-01-01

    A versatile balloon borne hard X-ray experiment with a very large area (approx.= 1.1 m 2 ) and high spectral resolution has been developed for the study of the hard X-ray sources in the energy range 20-180 keV. The telescope consists of four multiwire proportional chambers (MWPC) that have a geometrical sensitive area of 2700 cm 2 each. The detector system has a sensitivity of approx.= 10 -5 photons cm -2 s -1 keV -1 during a typical balloon observation. A background rate of approx.= 3 x 10 -4 counts cm -2 s -1 keV -1 was observed in the operative energy range at 2.4 gm/cm 2 ceiling altitude and geographic latitude of 38 0 N. The design details, fabrication and flight performance of the instrument are briefly discussed with reference to the effectiveness of background reduction and other test parameters. (orig.)

  6. Center for X-Ray Optics, 1992

    International Nuclear Information System (INIS)

    1993-08-01

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

  7. Analysis of hard X-ray emission from selected very high energy γ-ray sources observed with INTEGRAL

    International Nuclear Information System (INIS)

    Hoffmann, Agnes Irene Dorothee

    2009-01-01

    A few years ago, the era of very high energy γ-ray astronomy started, when the latest generation of Imaging Atmospheric Cherenkov Telescopes (IACT) like H.E.S.S. began to operate and to resolve the sources of TeV emission. Identifications via multi-wavelength studies reveal that the detected sources are supernova remnants and active galactic nuclei, but also pulsar wind nebulae and a few binaries. One widely discussed open question is, how these sources are able to accelerate particles to such high energies. The understanding of the underlying particle distribution, the acceleration processes taking place, and the knowledge of the radiation processes which produce the observed emission, is, therefore, of crucial interest. Observations in the hard X-ray domain can be a key to get information on these particle distributions and processes. Important for this thesis are the TeV and the hard X-ray range. The two instruments, H.E.S.S. and INTEGRAL, whose data were used, are, therefore, described in detail. The main part of this thesis is focused on the X-ray binary system LS 5039/RX J1826.2-1450. It was observed in several energy ranges. The nature of the compact object is still not known, and it was proposed either to be a microquasar system or a non-accreting pulsar system. The observed TeV emission is modulated with the orbital cycle. Several explanations for this variability have been discussed in recent years. The observations with INTEGRAL presented in this thesis have provided new information to solve this question. Therefore, a search for a detection in the hard X-ray range and for its orbital dependence was worthwhile. Since LS 5039 is a faint source and the sky region where it is located is crowded, a very careful, non-standard handling of the INTEGRAL data was necessary, and a cross-checking with other analysis methods was essential to provide reliable results. We found that LS 5039 is emitting in the hard X-ray energy range. A flux rate and an upper flux

  8. Analysis of hard X-ray emission from selected very high energy {gamma}-ray sources observed with INTEGRAL

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, Agnes Irene Dorothee

    2009-11-13

    A few years ago, the era of very high energy {gamma}-ray astronomy started, when the latest generation of Imaging Atmospheric Cherenkov Telescopes (IACT) like H.E.S.S. began to operate and to resolve the sources of TeV emission. Identifications via multi-wavelength studies reveal that the detected sources are supernova remnants and active galactic nuclei, but also pulsar wind nebulae and a few binaries. One widely discussed open question is, how these sources are able to accelerate particles to such high energies. The understanding of the underlying particle distribution, the acceleration processes taking place, and the knowledge of the radiation processes which produce the observed emission, is, therefore, of crucial interest. Observations in the hard X-ray domain can be a key to get information on these particle distributions and processes. Important for this thesis are the TeV and the hard X-ray range. The two instruments, H.E.S.S. and INTEGRAL, whose data were used, are, therefore, described in detail. The main part of this thesis is focused on the X-ray binary system LS 5039/RX J1826.2-1450. It was observed in several energy ranges. The nature of the compact object is still not known, and it was proposed either to be a microquasar system or a non-accreting pulsar system. The observed TeV emission is modulated with the orbital cycle. Several explanations for this variability have been discussed in recent years. The observations with INTEGRAL presented in this thesis have provided new information to solve this question. Therefore, a search for a detection in the hard X-ray range and for its orbital dependence was worthwhile. Since LS 5039 is a faint source and the sky region where it is located is crowded, a very careful, non-standard handling of the INTEGRAL data was necessary, and a cross-checking with other analysis methods was essential to provide reliable results. We found that LS 5039 is emitting in the hard X-ray energy range. A flux rate and an upper

  9. X-ray refractometer

    International Nuclear Information System (INIS)

    Tur'yanskij, A.G.; Pirshin, I.V.

    2001-01-01

    Paper introduces a new circuit of X-ray refractometer to study angular and spectral features of refracted radiation within hard X-ray range. Refractometer incorporates two goniometers, two crystal-analyzers and three radiation detectors. The maximum distance between radiation source focal point and a receiving slit of the second goniometer is equal to 1.4 m. For the first time one obtained refraction patterns of fine-film specimens including C/Si stressed structure. Paper describes a new technique of refractometry via specimen oscillation at fixed position of a detecting device. Paper presents the measurement results of oscillation refraction patterns for specimens of melted quartz and ZnSe single crystal [ru

  10. FAST TIMING ANALYSIS OF CYGNUS X-1 USING THE SPECTROMETER ON THE INTERNATIONAL GAMMA-RAY ASTROPHYSICS LABORATORY

    International Nuclear Information System (INIS)

    Cabanac, Clement; Roques, Jean-Pierre; Jourdain, Elisabeth

    2011-01-01

    We report for the first time the high-frequency analysis of Cyg X-1 up to hard X-ray using the spectrometer on International Gamma-Ray Astrophysics Laboratory (INTEGRAL). After analyzing the possible contribution from the background, and using the INTEGRAL archive from 2005 March to 2008 May, power density spectra were obtained up to 130 keV. First, we show that their overall shape is very similar to that observed at lower energies as they are well described by sets of Lorentzians. The strength of this fast variability (up to 40 Hz) does not drop at high energy since we show that it remains at ∼25% rms, even in the highest energy bands. Second, the hard X-ray variability patterns of Cyg X-1 are state dependent: the softer the spectrum (or the lower the hardness ratio), the lower the total fractional variability and the higher the typical frequencies observed. The strength of the total variability as a function of energy and state is then investigated. By comparison with simultaneous and published RXTE/Proportional Counter Array data, we show that in the hard state it remains quite constant in the 2-130 keV energy range. In the softer state it is also flat up to 50 keV and may increase at higher energy. The implications of this behavior on the models are then discussed.

  11. Experimental study of hard X-rays emitted from meter-scale positive discharges in air

    NARCIS (Netherlands)

    P.O. Kochkin (Pavlo); C.V. Nguyen; A. van Deursen (Arie); U. M. Ebert (Ute)

    2012-01-01

    textabstractWe investigate structure and evolution of long positive spark breakdown; and we study at which stage pulses of hard x-rays are emitted. Positive high-voltage pulses of standardized lightning impulse wave form of about 1 MV were applied to about 1 m of ambient air. The discharge evolution

  12. Recent progress of hard x-ray imaging microscopy and microtomography at BL37XU of SPring-8

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Yoshio, E-mail: yoshio@spring8.or.jp; Takeuchi, Akihisa; Terada, Yasuko; Uesugi, Kentaro [Japan Synchrotron Radiation Research Institute (JASRI/SPring-8), Sayo, Hyogo 679-5198 (Japan); Mizutani, Ryuta [Department of Applied Biochemistry, Tokai University, Hiratsuka, Kanagawa 259-1292 (Japan)

    2016-01-28

    A hard x-ray imaging microscopy and microtomography system is now being developed at the beamline 37XU of SPring-8. In the latest improvement, a spatial resolution of about 50 nm is achieved in two-dimensional imaging at 6 keV x-ray energy using a Fresnel zone plate objective with an outermost zone width of 35 nm. In the tomographic measurement, a spatial resolution of about 100 nm is achieved at 8 keV using an x-ray guide tube condenser optic and a Fresnel zone plate objective with an outermost zone width of 50 nm.

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

    Science.gov (United States)

    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).

  14. Investigation of biomedical inner microstructures with hard X-ray phase-contrast imaging

    Energy Technology Data Exchange (ETDEWEB)

    Shu Hang [Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, CAS, 100049 Beijing (China); Graduate University of the Chinese Academy of Sciences, 100864 Beijing (China); Zhu Peiping [Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, CAS, 100049 Beijing (China); Chen Bo [Department of Physics, University of Science and Technology of China, Hefei 230026 (China); Liu Bo; Yin Hongxia [Capital University of Medical Sciences, 100054 Beijing (China); Li Enrong [Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, CAS, 100049 Beijing (China); Graduate University of the Chinese Academy of Sciences, 100864 Beijing (China); Liu Yijin [Department of Physics, University of Science and Technology of China, Hefei 230026 (China); Wang Junyue [Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, CAS, 100049 Beijing (China); Graduate University of the Chinese Academy of Sciences, 100864 Beijing (China); Yuan Qingxi; Huang Wanxia; Fang Shouxian [Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, CAS, 100049 Beijing (China); Wu Ziyu [Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, CAS, 100049 Beijing (China); National Center for NanoScience and Technology, 100080 Beijing (China)], E-mail: wuzy@ihep.ac.cn

    2007-09-21

    Hard X-ray Phase-Contrast Imaging (HX-PCI) is a new and valuable method that may provide information of the inner parts of an opaque object. Previous reports demonstrated its applicability in soft and hard tissue imaging. Here we provide further evidence for improved image quality and the effective capability to distinguish inner microstructures in real biomedical systems such as cochlea. Experiments performed both at the 4W1A beamline of the Beijing Synchrotron Radiation Facility (BSRF) and at the Taiwan National Synchrotron Radiation Research Center (NSRRC) clearly show details of samples' inner microstructure with a resolution of a few microns. The improved spatial resolution is a relevant achievement for future improved understanding and clinical trials.

  15. Neutron and hard x-ray measurements during pellet deposition in TFTR

    Energy Technology Data Exchange (ETDEWEB)

    Heidbrink, W.W.; Milora, S.L.; Schmidt, G.L.; Schneider, W.; Ramsey, A.

    1986-06-01

    Measurements of neutrons and hard x rays are made with a pair of plastic scintillators during injection of deuterium pellets into deuterium TFTR plasmas. Three cases are investigated. During ohmic heating in plasmas with few runaway electrons, the neutron emission does not increase when a pellet is injected, indicating that strong acceleration of the pellet ions does not occur. In ohmic plasmas with low but detectable levels of runaway electrons, an x-ray burst is observed on a detector near the pellet injector as the pellet ablates, while a detector displaced 126/sup 0/ toroidally from the injector does not measure a synchronous burst. Reduced pellet penetration correlates with the presence of x-ray emission, suggesting that the origin of the burst is bremsstrahlung from runaway electrons that strike the solid pellet. In deuterium beam-heated discharges, an increase in the d-d neutron emission is observed when the pellet ablates. In this case, the increase is due to fusion reactions between beam ions and the high density neutral and plasma cloud produced by ablation of the pellet; this localized density perturbation equilibrates in about 700 ..mu..sec. Analysis of the data indicates that the density propagates without forming a sharp shock front with a rapid initial propagation velocity (greater than or equal to 2 x 10/sup 7/ cm/sec) that subsequently decreases to around 3 x 10/sup 6/ cm/sec. Modelling suggests that the electron heat flux into the pellet cloud is much less than the classical Spitzer value.

  16. Reflections on hard X-ray photon-in/photon-out spectroscopy for electronic structure studies

    Energy Technology Data Exchange (ETDEWEB)

    Glatzel, Pieter, E-mail: glatzel@esrf.fr [European Synchrotron Radiation Facility, 6 Rue Jules Horowitz, 38043 Grenoble (France); Weng, Tsu-Chien; Kvashnina, Kristina; Swarbrick, Janine; Sikora, Marcin [European Synchrotron Radiation Facility, 6 Rue Jules Horowitz, 38043 Grenoble (France); Gallo, Erik [European Synchrotron Radiation Facility, 6 Rue Jules Horowitz, 38043 Grenoble (France); Department of Inorganic, Physical and Materials Chemistry, INSTM Reference Center and NIS Centre of Excellence, Università di Torino, Via P. Giuria 7, I-10125 Torino (Italy); Smolentsev, Nikolay [European Synchrotron Radiation Facility, 6 Rue Jules Horowitz, 38043 Grenoble (France); Research Center for Nanoscale Structure of Matter, Southern Federal University, str. Zorge 5, 344090 Rostov-on-Don (Russian Federation); Mori, Roberto Alonso [European Synchrotron Radiation Facility, 6 Rue Jules Horowitz, 38043 Grenoble (France)

    2013-06-15

    Highlights: ► Overview of some recent developments in hard X-ray RXES/RIXS. ► Evaluation of spectral line broadening in RXES/RIXS. ► Modelling of RXES/RIXS by ground state DFT calculations. ► Discussion on when HERFD provides a good approximation to XAS. -- Abstract: An increasing community of researchers in various fields of natural sciences is combining X-ray absorption with X-ray emission spectroscopy (XAS–XES) to study electronic structure. With the applications becoming more diverse, the objectives and the requirements in photon-in/photon-out spectroscopy are becoming broader. It is desirable to find simple experimental protocols, robust data reduction and theoretical tools that help the experimentalist to understand their data and learn about the electronic structure. This article presents a collection of considerations on non-resonant and resonant XES with the aim to guide the experimentalist to make good use of this technique.

  17. SPATIALLY RESOLVED [Fe II] 1.64 μm EMISSION IN NGC 5135: CLUES FOR UNDERSTANDING THE ORIGIN OF THE HARD X-RAYS IN LUMINOUS INFRARED GALAXIES

    International Nuclear Information System (INIS)

    Colina, L.; Pereira-Santaella, M.; Alonso-Herrero, A.; Arribas, S.; Bedregal, A. G.

    2012-01-01

    Spatially resolved near-IR and X-ray imaging of the central region of the luminous infrared galaxy (LIRG) NGC 5135 is presented. The kinematical signatures of strong outflows are detected in the [Fe II] 1.64 μm emission line in a compact region at 0.9 kpc from the nucleus. The derived mechanical energy release is consistent with a supernova rate of 0.05-0.1 yr –1 . The apex of the outflowing gas spatially coincides with the strongest [Fe II] emission peak and with the dominant component of the extranuclear hard X-ray emission. All these features provide evidence for a plausible direct physical link between supernova-driven outflows and the hard X-ray emitting gas in an LIRG. This result is consistent with model predictions of starbursts concentrated in small volumes and with high thermalization efficiencies. A single high-mass X-ray binary (HMXB) as the major source of the hard X-ray emission, although not favored, cannot be ruled out. Outside the active galactic nucleus, the hard X-ray emission in NGC 5135 appears to be dominated by the hot interstellar medium produced by supernova explosions in a compact star-forming region, and not by the emission due to HMXBs. If this scenario is common to (ultra)luminous infrared galaxies, the hard X-rays would only trace the most compact (≤100 pc) regions with high supernova and star formation densities, therefore a lower limit to their integrated star formation. The star formation rate derived in NGC 5135 based on its hard X-ray luminosity is a factor of two and four lower than the values obtained from the 24 μm and soft X-ray luminosities, respectively.

  18. Modelling properties of hard x-rays generated by the interaction between relativistic electrons and very intense laser beams

    International Nuclear Information System (INIS)

    Popa, Alexandru

    2009-01-01

    In a previous paper we presented a calculation model for high harmonic generation by relativistic Thomson scattering of the electromagnetic radiation by free electrons. In this paper we present a similar model for the calculation of the energies of hard x-rays (20- 200 keV) resulted from the interaction between relativistic electrons (20-100 MeV) and very intense laser beams. Starting from the relativistic equations of motion of an electron in the electromagnetic field we show that the Lienard-Wiechert equation leads to electromagnetic waves whose frequencies are in the domain of hard x-rays. When the relativistic parameter of the laser beam is greater than unity, the model predicts the existence of harmonics of the above frequencies. Our theoretical values are in good agreement with experimental values of the x-ray energies from the literature and predict accurately their angular distribution.

  19. Design and development of the SIMBOL-X hard x-ray optics

    Science.gov (United States)

    Pareschi, G.; Attinà, P.; Basso, S.; Borghi, G.; Burkert, W.; Buzzi, R.; Citterio, O.; Civitani, M.; Conconi, P.; Cotroneo, V.; Cusumano, G.; Dell'Orto, E.; Freyberg, M.; Hartner, G. D.; Gorenstein, P.; Mattaini, E.; Mazzoleni, F.; Parodi, G.; Romaine, S.; Spiga, D.; Tagliaferri, G.; Valtolina, R.; Valsecchi, G.; Vernani, D.

    2008-07-01

    The SIMBOL-X formation-flight X-ray mission will be operated by ASI and CNES in 2014, with a large participation of the French and Italian high energy astrophysics scientific community. Also German and US Institutions are contributing in the implementation of the scientific payload. Thanks to the formation-flight architecture, it will be possible to operate a long (20 m) focal length grazing incidence mirror module, formed by 100 confocal multilayer-coated Wolter I shells. This system will allow us to focus X-rays over a very broad energy band, from 0.5 keV up to 80 keV and beyond, with more than two orders of magnitude improvement in angular resolution (20 arcsec HEW) and sensitivity (0.5 µCrab on axis @30 keV) compared to non focusing detectors used so far. The X-ray mirrors will be realized by Ni electroforming replication, already successfully used for BeppoSAX, XMM-Newton, and JET-X/SWIFT; the thickness trend will be about two times less than for XMM, in order to save mass. Multilayer reflecting coatings will be implemented, in order to improve the reflectivity beyond 10 keV and to increase the field of view 812 arcmin at 30 keV). In this paper, the SIMBOL-X optics design, technology and implementation challenges will be discussed; it will be also reported on recent results obtained in the context of the SIMBOL-X optics development activities.

  20. Conceptual design of the tomographic system for simultaneous studying of soft and hard X-ray emission from dense magnetized plasma

    Energy Technology Data Exchange (ETDEWEB)

    Bielecki, J., E-mail: jakub.bielecki@ifj.edu.edu; Wójcik-Gargula, A.; Scholz, M.

    2016-11-15

    The article presents a new approach for investigation of spatial distributions of soft and hard X-rays emitted from dense magnetized plasma. The approach is based on the application of tomographic methods to the X-ray emission reconstruction in a plasma focus (PF) device. Quantitative investigation of the anisotropy of the reconstructed X–ray plasma emissivity may help to explain the nature of fusion reaction mechanisms in a PF device. The aim of this work is to present a conceptual design of a novel dual-energy X-ray emission tomographic system dedicated to the PF-24 plasma focus device. The system, which enables the simultaneous registration of soft and hard X-rays, is composed of three X‐ray pinhole cameras. Each camera is equipped with a pair of 16-element Si photodiode arrays arranged in two layers separated by an aluminum attenuator. The Geant4 code was used to optimize the layout and parameters of the applied detectors. In addition, a method of tomographic reconstruction from a sparse data set provided by the experimental setup has been presented.

  1. Design and performance of a one square meter proportional counter system for hard X-ray astronomy

    Energy Technology Data Exchange (ETDEWEB)

    Bazzano, A.; Boccaccini, L.; La Padula, C.D.; Mastropietro, M.; Patriarca, R.; Polcaro, F.; Ubertini, P. (Consiglio Nazionale delle Ricerche, Frascati (Italy). Lab. di Astrofisica Spaziale); Manchanda, R.K. (Consiglio Nazionale delle Ricerche, Frascati (Italy). Lab. di Astrofisica Spaziale; Tata Inst. of Fundamental Research, Bombay (India))

    1983-09-01

    A versatile balloon borne hard X-ray experiment with a very large area (approx.= 1.1 m/sup 2/) and high spectral resolution has been developed for the study of the hard X-ray sources in the energy range 20-180 keV. The telescope consists of four multiwire proportional chambers (MWPC) that have a geometrical sensitive area of 2700 cm/sup 2/ each. The detector system has a sensitivity of approx.= 10/sup -5/ photons cm/sup -2/ s/sup -1/ keV/sup -1/ during a typical balloon observation. A background rate of approx.= 3 x 10/sup -4/ counts cm/sup -2/ s/sup -1/ keV/sup -1/ was observed in the operative energy range at 2.4 gm/cm/sup 2/ ceiling altitude and geographic latitude of 38/sup 0/N. The design details, fabrication and flight performance of the instrument are briefly discussed with reference to the effectiveness of background reduction and other test parameters.

  2. Spatially Resolved Hard X-ray Emission in the Central 5 kpc of the Galaxy Merger NGC 6240

    Science.gov (United States)

    Wang, Junfeng; Nardini, E.; Fabbiano, G.; Karovska, M.; Elvis, M.; Pellegrini, S.; Max, C. E.; Risaliti, G.; U, V.; Zezas, A.

    2013-04-01

    We have obtained a deep, sub-arcsecond resolution X-ray image of the nuclear region of the luminous galaxy merger NGC 6240 with Chandra, which resolves the X-ray emission from the pair of active nuclei and the diffuse hot gas in great detail. We detect extended hard X-ray emission from 70 million K hot gas over a spatial scale of 5 kpc, indicating the presence of fast shocks with velocity of 2200 km/s. For the first time we obtain spatial distribution of this highly ionized gas emitting FeXXV and find that it shows a remarkable correspondence to the large scale morphology of H_2(1-0) S(1) line emission and Hα filaments. Propagation of fast shocks originated in the starburst driven wind into the ambient dense gas can account for this morphological correspondence. Both the energetics and the iron mass in the hot gas are consistent with the expected injection from the supernovae explosion during the starburst that is commensurate with its high star formation rate.

  3. Hard X-ray phase-contrast microscope for observing transparent specimens

    Energy Technology Data Exchange (ETDEWEB)

    Kagoshima, Y.; Yokoyama, Y.; Niimi, T.; Koyama, T.; Tsusaka, Y.; Matsui, J. [Himeji Institute of Technology, Graduate School of Science, Hyogo (Japan); Takai, K. [Japan synchrotron Radiation Research Institute, Mikazuki, Hyogo (Japan)

    2002-08-01

    A hard X-ray transmission imaging microscope has been in use at the beamline BL24XU of Spring-8. It makes use of a phase zone plate made of tantalum as its X-ray lens, and is capable of imaging the structure as fine as 125-nm line-and-space pattern. The Zernike's phase-contrast method has been implemented to the microscope with phase plates made of gold. The photon energy was tuned to 12 keV just above the L{sub 3} absorption edge of gold (11.9 keV) in order to increase the image contrast. Polystyrene micro particles as transparent specimens were imaged clearly in the opposite image contrast with phase plates to shift the phase of the central order spectra in the back focal plane of the objective by one-quarter and three-quarters of a period, while the absorption contrast image showed little image contrast. Performance of the newly developed phase zone plate has been tested and it was confirmed that the structure as fine as 60-mm line-and-space pattern was able to be imaged. (authors)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-01-13

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

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

    International Nuclear Information System (INIS)

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

    2008-01-01

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

  6. THERMAL EMISSION IN THE EARLY X-RAY AFTERGLOWS OF GAMMA-RAY BURSTS: FOLLOWING THE PROMPT PHASE TO LATE TIMES

    Energy Technology Data Exchange (ETDEWEB)

    Friis, Mette [Centre for Astrophysics and Cosmology, Science Institute, University of Iceland, Dunhagi 5, 107 Reykjavik (Iceland); Watson, Darach, E-mail: mef4@hi.is, E-mail: darach@dark-cosmology.dk [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen O (Denmark)

    2013-07-01

    Thermal radiation, peaking in soft X-rays, has now been detected in a handful of gamma-ray burst (GRB) afterglows and has to date been interpreted as shock break-out of the GRB's progenitor star. We present a search for thermal emission in the early X-ray afterglows of a sample of Swift bursts selected by their brightness in X-rays at early times. We identify a clear thermal component in eight GRBs and track the evolution. We show that at least some of the emission must come from highly relativistic material since two show an apparent super-luminal expansion of the thermal component. Furthermore, we determine very large luminosities and high temperatures for many of the components-too high to originate in a supernova shock break-out. Instead, we suggest that the component may be modeled as late photospheric emission from the jet, linking it to the apparently thermal component observed in the prompt emission of some GRBs at gamma-ray and hard X-ray energies. By comparing the parameters from the prompt emission and the early afterglow emission, we find that the results are compatible with the interpretation that we are observing the prompt quasi-thermal emission component in soft X-rays at a later point in its evolution.

  7. Polymer Compund Refractive Lenses for Hard X-ray Nanofocusing

    OpenAIRE

    Krywka, Christina; Last, Arndt; Marschall, Felix; Markus, Otto; Georgi, Sebastian; Mueller, Martin; Mohr, Jürgen

    2016-01-01

    Compound refractive lenses fabricated out of SU-8 negative photoresist have been used to generate a nanofocused, i.e. sub-μm sized X-ray focal spot at an X-ray nanodiffraction setup. X-ray microscopy and X-ray diffraction techniques have conceptually different demands on nanofocusing optical elements and so with the application of X-ray nanodiffraction in mind, this paper presents the results of an initial characterization of polymer lenses used as primary focusin...

  8. Microjet formation and hard x-ray production from a liquid metal target irradiated by intense femtosecond laser pulses

    Energy Technology Data Exchange (ETDEWEB)

    Lar' kin, A., E-mail: alexeylarkin@yandex.ru; Uryupina, D.; Ivanov, K.; Savel' ev, A., E-mail: abst@physics.msu.ru [International Laser Center and Faculty of Physics, Lomonosov Moscow State University, Moscow 119991 (Russian Federation); Bonnet, T.; Gobet, F.; Hannachi, F.; Tarisien, M.; Versteegen, M. [Centre d' Études Nucléaires de Bordeaux-Gradignan, University of Bordeaux-CNRS-IN2P3, 33170 Gradignan (France); Spohr, K. [School of Engineering, University of the West of Scotland, Paisley, Scotland PA1 2BE (United Kingdom); Breil, J.; Chimier, B.; Dorchies, F.; Fourment, C.; Leguay, P.-M.; Tikhonchuk, V. T. [Centre Lasers Intenses et Applications, University of Bordeaux-CNRS-CEA, Talence 33405 (France)

    2014-09-15

    By using a liquid metal as a target one may significantly enhance the yield of hard x-rays with a sequence of two intense femtosecond laser pulses. The influence of the time delay between the two pulses is studied experimentally and interpreted with numerical simulations. It was suggested that the first arbitrary weak pulse produces microjets from the target surface, while the second intense pulse provides an efficient electron heating and acceleration along the jet surface. These energetic electrons are the source of x-ray emission while striking the target surface. The microjet formation is explained based on the results given by both optical diagnostics and hydrodynamic modeling by a collision of shocks originated from two distinct zones of laser energy deposition.

  9. Microjet formation and hard x-ray production from a liquid metal target irradiated by intense femtosecond laser pulses

    International Nuclear Information System (INIS)

    Lar'kin, A.; Uryupina, D.; Ivanov, K.; Savel'ev, A.; Bonnet, T.; Gobet, F.; Hannachi, F.; Tarisien, M.; Versteegen, M.; Spohr, K.; Breil, J.; Chimier, B.; Dorchies, F.; Fourment, C.; Leguay, P.-M.; Tikhonchuk, V. T.

    2014-01-01

    By using a liquid metal as a target one may significantly enhance the yield of hard x-rays with a sequence of two intense femtosecond laser pulses. The influence of the time delay between the two pulses is studied experimentally and interpreted with numerical simulations. It was suggested that the first arbitrary weak pulse produces microjets from the target surface, while the second intense pulse provides an efficient electron heating and acceleration along the jet surface. These energetic electrons are the source of x-ray emission while striking the target surface. The microjet formation is explained based on the results given by both optical diagnostics and hydrodynamic modeling by a collision of shocks originated from two distinct zones of laser energy deposition

  10. Microjet formation and hard x-ray production from a liquid metal target irradiated by intense femtosecond laser pulses

    Science.gov (United States)

    Lar'kin, A.; Uryupina, D.; Ivanov, K.; Savel'ev, A.; Bonnet, T.; Gobet, F.; Hannachi, F.; Tarisien, M.; Versteegen, M.; Spohr, K.; Breil, J.; Chimier, B.; Dorchies, F.; Fourment, C.; Leguay, P.-M.; Tikhonchuk, V. T.

    2014-09-01

    By using a liquid metal as a target one may significantly enhance the yield of hard x-rays with a sequence of two intense femtosecond laser pulses. The influence of the time delay between the two pulses is studied experimentally and interpreted with numerical simulations. It was suggested that the first arbitrary weak pulse produces microjets from the target surface, while the second intense pulse provides an efficient electron heating and acceleration along the jet surface. These energetic electrons are the source of x-ray emission while striking the target surface. The microjet formation is explained based on the results given by both optical diagnostics and hydrodynamic modeling by a collision of shocks originated from two distinct zones of laser energy deposition.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-12-31

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

  12. Hard X-ray observation of cygnus X-3

    International Nuclear Information System (INIS)

    Kendziorra, E.; Staubert, R.; Reppin, C.; Pietsch, W.; Truemper, J.; Voges, W.

    1979-05-01

    During a balloon observation on October 18, 1977 the high energy X-ray spectrum (20 - 90 keV) of Cyg X-3 has been measured with high statistical accuracy. It is found to be consistent with a thermal bremsstrahlung spectrum with kT = 17.5 +3.1/-2.6 keV or a power law Esup(γ) of the differential photon flux spectrum with γ=3.6 +-0.3. The extrapolation of the observed spectrum to approximately 100 MeV yields a gamma ray intensity which is at least three orders of magnitude below the intensity found by SAS-2 (Lamb et al. 1977). This indicates that the overall spectral behaviour of Cygnus X-3 is much different from that of the Crab- and Vela-pulsar. (orig.) [de

  13. Practical chemical analysis of Pt and Pd based heterogeneous catalysts with hard X-ray photoelectron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Yoshikawa, H., E-mail: YOSHIKAWA.Hideki@nims.go.jp [National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Matolínová, I.; Matolín, V. [Charles University in Prague, Faculty of Mathematics and Physics, V Holešovičkách 2, 18000 Prague 8 (Czech Republic)

    2013-10-15

    Highlights: •Hard X-ray photoelectron spectroscopy (HAXPES) enables interface analysis of catalyst. •HAXPES enables overall analysis of porous film of Pt-doped CeO{sub 2} and related catalyst. •HAXPES enables analysis of trace elements for Pd and Pt{sub 3}Ni nanoparticle catalysts. -- Abstract: Interfacial properties including configuration, porosity, chemical states, and atomic diffusion greatly affect the performance of supported heterogeneous catalysts. Hard X-ray photoelectron spectroscopy (HAXPES) can be used to analyze the interfaces of heterogeneous catalysts because of its large information depth of more than 20 nm. We use HAXPES to examine Pt-doped CeO{sub 2} and related thin film catalysts evaporated on Si, carbon, and carbon nanotube substrates, because Pt-doped CeO{sub 2} has great potential as a noble metal-based heterogeneous catalyst for fuel cells. The HAXPES measurements clarify that the dopant material, substrate material, and surface pretreatment of substrate are important parameters that affect the interfacial properties of Pt-doped CeO{sub 2} and related thin film catalysts. Another advantage of HAXPES measurement of heterogeneous catalysts is that it can be used for chemical analysis of trace elements by detecting photoelectrons from deep core levels, which have large photoionization cross-sections in the hard X-ray region. We use HAXPES for chemical analysis of trace elements in Pd nanoparticle catalysts immobilized on sulfur-terminated substrates and Pt{sub 3}Ni nanoparticle catalysts enveloped by dendrimer molecules.

  14. Time-resolved X-ray PIV technique for diagnosing opaque biofluid flow with insufficient X-ray fluxes.

    Science.gov (United States)

    Jung, Sung Yong; Park, Han Wook; Kim, Bo Heum; Lee, Sang Joon

    2013-05-01

    X-ray imaging is used to visualize the biofluid flow phenomena in a nondestructive manner. A technique currently used for quantitative visualization is X-ray particle image velocimetry (PIV). Although this technique provides a high spatial resolution (less than 10 µm), significant hemodynamic parameters are difficult to obtain under actual physiological conditions because of the limited temporal resolution of the technique, which in turn is due to the relatively long exposure time (~10 ms) involved in X-ray imaging. This study combines an image intensifier with a high-speed camera to reduce exposure time, thereby improving temporal resolution. The image intensifier amplifies light flux by emitting secondary electrons in the micro-channel plate. The increased incident light flux greatly reduces the exposure time (below 200 µs). The proposed X-ray PIV system was applied to high-speed blood flows in a tube, and the velocity field information was successfully obtained. The time-resolved X-ray PIV system can be employed to investigate blood flows at beamlines with insufficient X-ray fluxes under specific physiological conditions. This method facilitates understanding of the basic hemodynamic characteristics and pathological mechanism of cardiovascular diseases.

  15. Caliste 64, a new CdTe micro-camera for hard X-ray spectro-imaging

    Science.gov (United States)

    Meuris, A.; Limousin, O.; Lugiez, F.; Gevin, O.; Blondel, C.; Pinsard, F.; Vassal, M. C.; Soufflet, F.; Le Mer, I.

    2009-10-01

    In the frame of the Simbol-X mission of hard X-ray astrophysics, a prototype of micro-camera with 64 pixels called Caliste 64 has been designed and several samples have been tested. The device integrates ultra-low-noise IDeF-X V1.1 ASICs from CEA and a 1 cm 2 Al Schottky CdTe detector from Acrorad because of its high uniformity and spectroscopic performance. The process of hybridization, mastered by the 3D Plus company, respects space applications standards. The camera is a spectro-imager with time-tagging capability. Each photon interacting in the semiconductor is tagged with a time, a position and an energy. Time resolution is better than 100 ns rms for energy deposits greater than 20 keV, taking into account electronic noise and technological dispersal of the front-end electronics. The spectrum summed across the 64 pixels results in an energy resolution of 664 eV fwhm at 13.94 keV and 842 eV fwhm at 59.54 keV, when the detector is cooled down to -10 °C and biased at -500 V.

  16. Caliste 64, a new CdTe micro-camera for hard X-ray spectro-imaging

    International Nuclear Information System (INIS)

    Meuris, A.; Limousin, O.; Lugiez, F.; Gevin, O.; Blondel, C.; Pinsard, F.; Vassal, M.C.; Soufflet, F.; Le Mer, I.

    2009-01-01

    In the frame of the Simbol-X mission of hard X-ray astrophysics, a prototype of micro-camera with 64 pixels called Caliste 64 has been designed and several samples have been tested. The device integrates ultra-low-noise IDeF-X V1.1 ASICs from CEA and a 1 cm 2 Al Schottky CdTe detector from Acrorad because of its high uniformity and spectroscopic performance. The process of hybridization, mastered by the 3D Plus company, respects space applications standards. The camera is a spectro-imager with time-tagging capability. Each photon interacting in the semiconductor is tagged with a time, a position and an energy. Time resolution is better than 100 ns rms for energy deposits greater than 20 keV, taking into account electronic noise and technological dispersal of the front-end electronics. The spectrum summed across the 64 pixels results in an energy resolution of 664 eV fwhm at 13.94 keV and 842 eV fwhm at 59.54 keV, when the detector is cooled down to -10 deg. C and biased at -500 V.

  17. Caliste 64, a new CdTe micro-camera for hard X-ray spectro-imaging

    Energy Technology Data Exchange (ETDEWEB)

    Meuris, A. [CEA, Irfu, Service d' Astrophysique, Bat. 709, Orme des Merisiers, F-91191 Gif-sur-Yvette (France)], E-mail: aline.meuris@cea.fr; Limousin, O. [CEA, Irfu, Service d' Astrophysique, Bat. 709, Orme des Merisiers, F-91191 Gif-sur-Yvette (France); Lugiez, F.; Gevin, O. [CEA, Irfu, Service d' Electronique, de Detecteurs et d' Informatique, F-91191 Gif-sur-Yvette (France); Blondel, C.; Pinsard, F. [CEA, Irfu, Service d' Astrophysique, Bat. 709, Orme des Merisiers, F-91191 Gif-sur-Yvette (France); Vassal, M.C.; Soufflet, F. [3D Plus, 641 rue Helene Boucher, F-78532 Buc (France); Le Mer, I. [CEA, Irfu, Service d' Astrophysique, Bat. 709, Orme des Merisiers, F-91191 Gif-sur-Yvette (France)

    2009-10-21

    In the frame of the Simbol-X mission of hard X-ray astrophysics, a prototype of micro-camera with 64 pixels called Caliste 64 has been designed and several samples have been tested. The device integrates ultra-low-noise IDeF-X V1.1 ASICs from CEA and a 1 cm{sup 2} Al Schottky CdTe detector from Acrorad because of its high uniformity and spectroscopic performance. The process of hybridization, mastered by the 3D Plus company, respects space applications standards. The camera is a spectro-imager with time-tagging capability. Each photon interacting in the semiconductor is tagged with a time, a position and an energy. Time resolution is better than 100 ns rms for energy deposits greater than 20 keV, taking into account electronic noise and technological dispersal of the front-end electronics. The spectrum summed across the 64 pixels results in an energy resolution of 664 eV fwhm at 13.94 keV and 842 eV fwhm at 59.54 keV, when the detector is cooled down to -10 deg. C and biased at -500 V.

  18. Frontiers in X-Ray Science

    International Nuclear Information System (INIS)

    Young, Linda

    2011-01-01

    The year 2010 marked the fiftieth anniversary of the optical laser and the first anniversary of the world's first hard x-ray free-electron laser, the Linac Coherent Light Source (LCLS) at SLAC. This exciting, new accelerator-based source of x-rays provides peak brilliances roughly a billion times greater than currently available from synchrotron sources such as the Advanced Photon Source at Argonne, and thus explores a qualitatively different parameter space. This talk will describe the first experiments at the LCLS aimed at understanding the nature of high intensity x-ray interactions, related applications in ultrafast imaging on the atomic scale and sketch nascent plans for the extension of both linac and storage-ring based photon sources.

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

    Energy Technology Data Exchange (ETDEWEB)

    Kawate, T. [Kwasan and Hida Observatory, Kitashirakawa-oiwakecho, Sakyo, Kyoto 606-8502 (Japan); Nishizuka, N. [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Chuo-ku, Sagamihara, Kanagawa 229-8510 (Japan); Oi, A. [College of Science, Ibaraki University, Mito, Ibaraki 310-8512 (Japan); Ohyama, M. [Faculty of Education, Shiga University, 2-5-1 Hiratsu, Otsu, Shiga 1-1, Baba Hikone city, Siga 522-8522 (Japan); Nakajima, H., E-mail: kawate@kusastro.kyoto-u.ac.jp [Nobeyama Solar Radio Observatory, NAOJ, Nobeyama, Minamisaku, Nagano 384-1305 (Japan)

    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.

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

    DEFF Research Database (Denmark)

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

    2005-01-01

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

  1. The X-ray Astronomy Recovery Mission

    Science.gov (United States)

    Tashiro, M.; Kelley, R.

    2017-10-01

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

  2. Calibration of the High Energy Replicated Optics to Explore the Sun (HEROES) Hard X-ray Telescope

    Science.gov (United States)

    Wilson-Hodge, Colleen A.; Gaskin, Jessica; Christe, Steven; Shih, Albert; Tennant, Allyn; Swartz, Doug; Kilaru, Kiranmayee; Elsner, Ron; Kolodziejczak, Jeff; Ramsey, Brian

    2014-01-01

    On September 21-22, 2013, the High Energy Replicated Optics to Explore the Sun (HEROES) hard X-ray telescope, flew as a balloon payload from Ft. Sumner, N.M. HEROES observed the Sun, the black hole binary GRS 1915+105, and the Crab Nebula during its 27 hour flight. In this paper we describe laboratory calibration measurements of the HEROES detectors using line and continuum sources, applications of these measurements to define channel to energy (gain) corrections for observed events and to define detector response matrices. We characterize the HEROES X-ray grazing incidence optics using measurements taken in the Stray-Light (SLF) Facility in Huntsville, AL, and using ray traces.

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

    Science.gov (United States)

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

    2017-08-01

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

  4. Hard x-ray phase contrastmicroscopy - techniques and applications

    Science.gov (United States)

    Holzner, Christian

    In 1918, Einstein provided the first description of the nature of the refractive index for X-rays, showing that phase contrast effects are significant. A century later, most x-ray microscopy and nearly all medical imaging remains based on absorption contrast, even though phase contrast offers orders of magnitude improvements in contrast and reduced radiation exposure at multi-keV x-ray energies. The work presented is concerned with developing practical and quantitative methods of phase contrast for x-ray microscopy. A theoretical framework for imaging in phase contrast is put forward; this is used to obtain quantitative images in a scanning microscope using a segmented detector, and to correct for artifacts in a commercial phase contrast x-ray nano-tomography system. The principle of reciprocity between scanning and full-field microscopes is then used to arrive at a novel solution: Zernike contrast in a scanning microscope. These approaches are compared on a theoretical and experimental basis in direct connection with applications using multi-keV x-ray microscopes at the Advanced Photon Source at Argonne National Laboratory. Phase contrast provides the best means to image mass and ultrastructure of light elements that mainly constitute biological matter, while stimulated x-ray fluorescence provides high sensitivity for studies of the distribution of heavier trace elements, such as metals. These approaches are combined in a complementary way to yield quantitative maps of elemental concentration from 2D images, with elements placed in their ultrastructural context. The combination of x-ray fluorescence and phase contrast poses an ideal match for routine, high resolution tomographic imaging of biological samples in the future. The presented techniques and demonstration experiments will help pave the way for this development.

  5. Center for X-ray Optics, 1988

    International Nuclear Information System (INIS)

    1989-04-01

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

  6. Flash X-Ray (FXR) Accelerator Optimization Electronic Time-Resolved Measurement of X-Ray Source Size

    International Nuclear Information System (INIS)

    Jacob, J; Ong, M; Wargo, P

    2005-01-01

    Lawrence Livermore National Laboratory (LLNL) is currently investigating various approaches to minimize the x-ray source size on the Flash X-Ray (FXR) linear induction accelerator in order to improve x-ray flux and increase resolution for hydrodynamic radiography experiments. In order to effectively gauge improvements to final x-ray source size, a fast, robust, and accurate system for measuring the spot size is required. Timely feedback on x-ray source size allows new and improved accelerator tunes to be deployed and optimized within the limited run-time constraints of a production facility with a busy experimental schedule; in addition, time-resolved measurement capability allows the investigation of not only the time-averaged source size, but also the evolution of the source size, centroid position, and x-ray dose throughout the 70 ns beam pulse. Combined with time-resolved measurements of electron beam parameters such as emittance, energy, and current, key limiting factors can be identified, modeled, and optimized for the best possible spot size. Roll-bar techniques are a widely used method for x-ray source size measurement, and have been the method of choice at FXR for many years. A thick bar of tungsten or other dense metal with a sharp edge is inserted into the path of the x-ray beam so as to heavily attenuate the lower half of the beam, resulting in a half-light, half-dark image as seen downstream of the roll-bar; by measuring the width of the transition from light to dark across the edge of the roll-bar, the source size can be deduced. For many years, film has been the imaging medium of choice for roll-bar measurements thanks to its high resolution, linear response, and excellent contrast ratio. Film measurements, however, are fairly cumbersome and require considerable setup and analysis time; moreover, with the continuing trend towards all-electronic measurement systems, film is becoming increasingly difficult and expensive to procure. Here, we shall

  7. Toward a fourth-generation X-ray source

    International Nuclear Information System (INIS)

    Monction, D. E.

    1999-01-01

    The field of synchrotron radiation research has grown rapidly over the last 25 years due to both the push of the accelerator and magnet technology that produces the x-ray beams and the pull of the extraordinary scientific research that is possible with them. Three successive generations of synchrotrons radiation facilities have resulted in beam brilliances 11 to 12 orders of magnitude greater than the standard laboratory x-ray tube. However, greater advances can be easily imagined given the fact that x-ray beams from present-day facilities do not exhibit the coherence or time structure so familiar with the optical laser. Theoretical work over the last ten years or so has pointed to the possibility of generating hard x-ray beams with laser-like characteristics. The concept is based on self-amplified spontaneous emission (SASE) in flee-electron lasers. A major facility of this type based upon a superconducting linac could produce a cost-effective facility that spans wave-lengths from the ultraviolet to the hard x-ray regime, simultaneously servicing large numbers experimenters from a wide range of disciplines. As with each past generation of synchrotrons facilities, immense new scientific opportunities would result from fourth-generation sources.

  8. Time switch for X-ray diagnosis apparatus

    Energy Technology Data Exchange (ETDEWEB)

    Distler, G; Goetzl, H

    1977-04-07

    A time switch for dental X-rays consists of a knob to select exposure time. Two scales are concentrically mounted, one for time, and one with the various tooth symbols, in such a way that the various teeth are in correspondence with the usually recommended times. However, should the X-ray tube characteristics vary at some stage, by pressing the knob, then turning, the 'tooth scale' can be rotated for setting the exposure times at higher or lower levels.

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

    OpenAIRE

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

    2016-01-01

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

  10. The background counting rates in a balloon borne hard X-ray telescope

    International Nuclear Information System (INIS)

    Dean, A.J.; Dipper, N.A.; Lewis, R.A.

    1986-01-01

    A detailed Monte Carlo model of a hard (20-300 keV) X-ray astronomical telescope has been developed in order to calculate the energy loss distribution of the unwanted background noise events in the prime detection elements. The spectral distributions of the background rates measured at balloon altitudes over Palestine, Texas are compared to the predictions of the theoretical model. Good agreement has been found in terms of both the overall intensity level as well as the spectral distribution. (orig.)

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

    DEFF Research Database (Denmark)

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

    2014-01-01

    We report NuSTAR observations of a sample of six X-ray weak broad absorption line (BAL) quasars. These targets, at z = 0.148-1.223, are among the optically brightest and most luminous BAL quasars known at z 330 times weaker than...... expected for typical quasars. Our results from a pilot NuSTAR study of two low-redshift BAL quasars, a Chandra stacking analysis of a sample of high-redshift BAL quasars, and a NuSTAR spectral analysis of the local BAL quasar Mrk 231 have already suggested the existence of intrinsically X-ray weak BAL...... quasars, i.e., quasars not emitting X-rays at the level expected from their optical/UV emission. The aim of the current program is to extend the search for such extraordinary objects. Three of the six new targets are weakly detected by NuSTAR with ≲ 45 counts in the 3-24 keV band, and the other three...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2004-07-01

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

  13. The advantages of soft X-rays and cryogenic spectrometers for measuring chemical speciation by X-ray spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Drury, Owen B. [Lawrence Livermore National Laboratory, Advanced Detector Group, 7000 East Ave., L-270, Livermore, CA 94550 (United States); UC Davis, Biophysics Graduate Group, 1 Shields Ave, CA 95616 (United States); LBNL, Advanced Biological and Environmental X-ray Facility, 1 Cyclotron Road, MS 6-2100, Berkeley, CA 92720 (United States); Friedrich, Stephan [Lawrence Livermore National Laboratory, Advanced Detector Group, 7000 East Ave., L-270, Livermore, CA 94550 (United States) and LBNL, Advanced Biological and Environmental X-ray Facility, 1 Cyclotron Road, MS 6-2100, Berkeley, CA 92720 (United States)]. E-mail: friedrich1@llnl.gov; George, Simon J. [LBNL, Advanced Biological and Environmental X-ray Facility, 1 Cyclotron Road, MS 6-2100, Berkeley, CA 92720 (United States); Cramer, Stephen P. [UC Davis, Biophysics Graduate Group, 1 Shields Ave, CA 95616 (United States); LBNL, Advanced Biological and Environmental X-ray Facility, 1 Cyclotron Road, MS 6-2100, Berkeley, CA 92720 (United States)

    2006-04-15

    We have built a 36-pixel high-resolution superconducting tunnel junction (STJ) soft X-ray spectrometer for chemical analysis of dilute metals by fluorescence-detected X-ray absorption spectroscopy (XAS) at the Advanced Light Source synchrotron. Soft X-ray absorption edges are preferred over traditional hard X-ray spectroscopy at the K-edges, since they have narrower natural linewidths and exhibit stronger chemical shifts. STJ detectors are preferred in the soft X-ray band over traditional Ge or grating spectrometers, since they have sufficient energy resolution to resolve transition metal L and M lines from light element K emission, and sufficient detection efficiency to measure the weak lines of dilute specimens within an acceptable time. We demonstrate the capabilities of our STJ spectrometer for chemical analysis with soft XAS measurements of molybdenum speciation on the Mo M{sub 4,5}-edges.

  14. Short irradiation time characteristics of the inverter type X-ray generator

    International Nuclear Information System (INIS)

    Miyazaki, Shigeru; Hara, Takamitu; Matutani, Kazuo; Saito, Kazuhiko.

    1994-01-01

    The linearity of the X-ray output is an important factor in radiography. It is a composite of the linearities of the X-ray tube voltage, the X-ray tube current, and the exposure time. This paper focuses on the linearity of exposure time. Non-linearity of the X-ray output for short-time exposure became a problem when the three-phase X-ray generator was introduced. This paper describes the inverter-type X-ray generator, which is expected to become predominant in the future. Previously, we investigated X-ray output linearity during short-time exposure using the technique of dynamic study. In this paper, we describe the application of a digital memory and a personal computer to further investigation. The non-linearity of the X-ray output was caused by irregular waveforms of the X-ray tube voltage found at the rise time and the fall time. When the rise time was about 0.6 ms, the non-linearity was about 2%, which is negligibly small. The non-linearity due to the fall time of the X-ray tube varied greatly according to the X-ray tube current. For the minimum irradiation time of 1 ms, 4% to 27% of the non-linearity was attributable to the fall time. The main cause was the stray capacitance of the X-ray high-voltage cables. When the X-ray tube current exceeded 400 mA, the rise time was almost equal to the fall time, and the problem did not occur. Consequently, the ideal generator should have a fall time which is equal to the rise time of the X-ray tube voltage. Strictly speaking, such a generator should have rectangular waveforms. (author)

  15. On the theory of time-resolved x-ray diffraction

    DEFF Research Database (Denmark)

    Henriksen, Niels Engholm; Møller, Klaus Braagaard

    2008-01-01

    We derive the basic theoretical formulation for X-ray diffraction with pulsed fields, using a fully quantized description of light and matter. Relevant time scales are discussed for coherent as well as incoherent X-ray pulses, and we provide expressions to be used for calculation...... of the experimental diffraction signal for both types of X-ray sources. We present a simple analysis of time-resolved X-ray scattering for direct bond breaking in diatomic molecules. This essentially analytical approach highlights the relation between the signal and the time-dependent quantum distribution...

  16. Symbiotic Stars in X-rays

    Science.gov (United States)

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

    2014-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-07-04

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

  18. Hard x-ray microimaging techniques based on phase zone plates

    International Nuclear Information System (INIS)

    Lai, B.; Yun, W.B.; Legnini, D.; Xiao, Y.H.; Chrzas, J.

    1992-01-01

    Phase zone plates of high focusing efficiency and submicron resolution have been demonstrated in the hard x-ray region. A scanning microscope based on these focusing optics will create many new applications. Preliminary results in the applications of the microscope are reported here. In the area of imaging, we have utilized absorption contrast to clearly identify the locations of Au and Ni constituents in a sample of two interleaved grids. Micro-EXAFS spectra has also been obtained on a Ni foil. Fluorescence from a nuclear fuel sample, as an example of microanalysis, has revealed the elemental distribution at the interfaces. Lastly, microdiffraction from AgBr crystallites has been studied. 5 figs, 7 refs

  19. Hard X-ray diffraction enhanced imaging only using two crystals

    Institute of Scientific and Technical Information of China (English)

    LI Gang; WANG Nan; WU Ziyu

    2004-01-01

    Different configurations for the monochromator crystals and the analyzer crystals have been used in hard X-ray diffraction enhanced imaging (DEI) methods to overcome the complex task to adjust each of them to the ideal position. Here we present a very compact DEI configuration, and preliminary results of experiments performed at the Beijing Synchrotron Radiation Facility (BSRF) using only two crystals: the first one acting as monochromator and the second one as analyzer in the Bragg geometry. Refraction contrast images characterized by high contrast and spatial resolution are obtained and compared with absorption images. Differences among these images will be outlined and discussed emphasizing the potential capabilities of this very simple layout that guarantees a high transmission efficiency.

  20. The 2014 X-Ray Minimum of η Carinae as Seen by Swift

    Energy Technology Data Exchange (ETDEWEB)

    Corcoran, M. F.; Hamaguchi, K. [CRESST and X-Ray Astrophysics Laboratory, NASA/Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Liburd, J.; Morris, D. [University of the Virgin Islands, College of Science and Mathematics, John Brewers Bay, St. Thomas, USVI 00802-9990 (United States); Russell, C. M. P. [NASA Goddard Space Flight Center, Code 662, Greenbelt, MD 20771 (United States); Gull, T. R. [NASA Goddard Space Flight Center, Code 667, Greenbelt, MD 20771 (United States); Madura, T. I. [Department of Physics and Astronomy, San Jose State University, One Washington Square, San Jose, CA 95192 (United States); Teodoro, M. [Universities Space Research Association, 7178 Columbia Gateway Drive, Columbia, MD 21044 (United States); Moffat, A. F. J. [Département de physique and Centre de Recherche en Astrophysique du Québec (CRAQ), Université de Montréal, C.P. 6128, Succ. Centre-Ville, Montréal, Québec, H3C 3J7 (Canada); Richardson, N. D. [Ritter Observatory, Department of Physics and Astronomy, The University of Toledo, Toledo, OH 43606 (United States); Hillier, D. J. [Department of Physics and Astronomy and Pittsburgh Particle Physics, Astrophysics, and Cosmology Center (PITT PACC), University of Pittsburgh, 3941 O’Hara Street, Pittsburgh, PA 15260 (United States); Damineli, A. [Instituto de Astronomia, Geofísica e Ciências Atmosféricas, Universidade de São Paulo, Rua do Matão 1226, Cidade Universitária, São Paulo, 05508-900 (Brazil); Groh, J. H. [School of Physics, Trinity College Dublin, Dublin 2 (Ireland)

    2017-03-20

    We report on Swift X-ray Telescope observations of Eta Carinae ( η Car), an extremely massive, long-period, highly eccentric binary obtained during the 2014.6 X-ray minimum/periastron passage. These observations show that η Car may have been particularly bright in X-rays going into the X-ray minimum state, while the duration of the 2014 X-ray minimum was intermediate between the extended minima seen in 1998.0 and 2003.5 by Rossi X-Ray Timing Explorer ( RXTE ), and the shorter minimum in 2009.0. The hardness ratios derived from the Swift observations showed a relatively smooth increase to a peak value occurring 40.5 days after the start of the X-ray minimum, though these observations cannot reliably measure the X-ray hardness during the deepest part of the X-ray minimum when contamination by the “central constant emission” component is significant. By comparing the timings of the RXTE and Swift observations near the X-ray minima, we derive an updated X-ray period of P {sub X} = 2023.7 ± 0.7 days, in good agreement with periods derived from observations at other wavelengths, and we compare the X-ray changes with variations in the He ii 4686 emission. The middle of the “Deep Minimum” interval, as defined by the Swift column density variations, is in good agreement with the time of periastron passage derived from the He ii λ 4686 line variations.

  1. DUAL-STAGE RECONNECTION DURING SOLAR FLARES OBSERVED IN HARD X-RAY

    International Nuclear Information System (INIS)

    Xu Yan; Jing Ju; Wang Haimin; Cao Wenda

    2010-01-01

    In this Letter, we present hard X-ray (HXR) observation by the Reuven Ramaty High Energy Solar Spectroscopic Imager of the 2003 October 29 X10 flare. Two pairs of HXR conjugate footpoints have been identified during the early impulsive phase. This geometric configuration is very much in the manner predicted by the 'tether-cutting' scenario first proposed by Moore and Roumeliotis. The HXR light curves show that the outer pair of footpoints disappeared much faster than the other pair. This temporal behavior further confirms that this event is a good example of the 'tether-cutting' model. In addition, we reconstructed a three-dimensional magnetic field based on the nonlinear force-free extrapolation and found that each pair of HXR footpoints were indeed linked by corresponding magnetic field lines.

  2. A Fabry-Perot interferometer for hard X-rays

    International Nuclear Information System (INIS)

    Caticha, A.; Caticha-Ellis, S.

    1990-01-01

    Reflection and transmission coefficients are calculated of a sequence of N thin parallel crystals diffracting close to normal incidence and separated by thin non-diffracting gaps. From the study of the particular case N=2 a new Fabry-Perot interferometer (FPI) is proposed for hard X-rays (wavelengths of the order of Angstroms). It is found that the FPI plates do not need to be carved from a single perfect crystal block but may be grown or cleaved by other methods. This interesting possibility is suggested by two facts. First, it is known that for incidence close to normal various features of dynamical diffraction are much less sensitive to crystal defects and crystal orientation. Second, the existence of a mismatch between the lattices of the two FPI plates may affect but does not qualitatively alter the performance of the FPI. It is shown that the optimal thickness of the plates is of the order of a few microns or less. The plates may be built from a wide variety of materials. The transmission of X-rays is studied as a function of the energy and direction of the incident photons for various values of the plate thickness, of the gap, of the lattice mismatch, and also for different materials in the gap. The transmission profile exhibits a peak which is spectrally very sharp (about 10 -3 eV for low order reflections and even less for higher ones) and which can be easily tuned by changing either the lattice mismatch or the temperature. FPI plates built of materials with low absorption such as graphite seem to be particularly convenient. Several possible applications are suggested. (author)

  3. Design of a radiation hard silicon pixel sensor for X-ray science

    Energy Technology Data Exchange (ETDEWEB)

    Schwandt, Joern

    2014-06-15

    At DESY Hamburg the European X-ray Free-Electron Laser (EuXFEL) is presently under construction. The EuXFEL has unique properties with respect to X-ray energy, instantaneous intensity, pulse length, coherence and number of pulses/sec. These properties of the EuXFEL pose very demanding requirements for imaging detectors. One of the detector systems which is currently under development to meet these challenges is the Adaptive Gain Integrating Pixel Detector, AGIPD. It is a hybrid pixel-detector system with 1024 x 1024 p{sup +} pixels of dimensions 200 μm x 200 μm, made of 16 p{sup +}nn{sup +}- silicon sensors, each with 10.52 cm x 2.56 cm sensitive area and 500 μm thickness. The particular requirements for the AGIPD are a separation between noise and single photons down to energies of 5 keV, more than 10{sup 4} photons per pixel for a pulse duration of less than 100 fs, negligible pile-up at the EuXFEL repetition rate of 4.5 MHz, operation for X-ray doses up to 1 GGy, good efficiency for X-rays with energies between 5 and 20 keV, and minimal inactive regions at the edges. The main challenge in the sensor design is the required radiation tolerance and high operational voltage, which is required to reduce the so-called plasma effect. This requires a specially optimized sensor. The X-ray radiation damage results in a build-up of oxide charges and interface traps which lead to a reduction of the breakdown voltage, increased leakage current, increased interpixel capacitances and charge losses. Extensive TCAD simulations have been performed to understand the impact of X-ray radiation damage on the detector performance and optimize the sensor design. To take radiation damage into account in the simulation, radiation damage parameters have been determined on MOS capacitors and gate-controlled diodes as function of dose. The optimized sensor design was fabricated by SINTEF. Irradiation tests on test structures and sensors show that the sensor design is radiation hard and

  4. Caliste 64, an innovative CdTe hard X-ray micro-camera

    International Nuclear Information System (INIS)

    Meuris, A.; Limousin, O.; Pinsard, F.; Le Mer, I.; Lugiez, F.; Gevin, O.; Delagnes, E.; Vassal, M.C.; Soufflet, F.; Bocage, R.

    2008-01-01

    A prototype 64 pixel miniature camera has been designed and tested for the Simbol-X hard X-ray observatory to be flown on the joint CNES-ASI space mission in 2014. This device is called Caliste 64. It is a high performance spectro-imager with event time-tagging capability, able to detect photons between 2 keV and 250 keV. Caliste 64 is the assembly of a 1 or 2 min thick CdTe detector mounted on top of a readout module. CdTe detectors equipped with Aluminum Schottky barrier contacts are used because of their very low dark current and excellent spectroscopic performance. Front-end electronics is a stack of four IDeF-X V1.1 ASICs, arranged perpendicular to the detection plane, to read out each pixel independently. The whole camera fits in a 10 * 10 * 20 mm 3 volume and is juxtaposable on its four sides. This allows the device to be used as an elementary unit in a larger array of Caliste 64 cameras. Noise performance resulted in an ENC better than 60 electrons rms in average. The first prototype camera is tested at -10 degrees C with a bias of -400 V. The spectrum summed across the 64 pixels results in a resolution of 697 eV FWHM at 13.9 keV and 808 eV FWFM at 59.54 keV. (authors)

  5. Real-time soft x-ray imaging on composite materials

    International Nuclear Information System (INIS)

    Polichar, R.

    1985-01-01

    The increased use of composite materials in aircraft structures has emphasized many of the unique and difficult aspects of the inspection of such components. Ultrasound has been extensively applied to certain configurations since it is relatively sensitive to laminar discontinuities in structure. Conversely, the use of conventional x-ray examination has been severely hampered by the fact that these composite materials are virtually transparent to the x-ray energies commonly encountered in industrial radiography (25 kv and above). To produce images with contrast approaching conventional radiography, one must use x-ray beams with average energies below 10 KEV where the absorption coefficients begin to rise rapidly for these low atomic number materials. This new regime of soft x-rays presents a major challenge to real-time imaging components. Special screen and window technology is required if these lower energy x-rays are to be effectively detected. Moreover, conventional x-ray tubes become very inefficient for generating the required x-ray flux at potentials much below 29 kv and the increased operating currents put significant limitations on conventional power sources. The purpose of this paper is to explore these special problems related to soft x-ray real-time imaging and to define the optimal technologies. Practical results obtained with the latest commerical and developmental instruments for real-time imaging will be shown. These instruments include recently developed imaging systems, new x-ray tubes and various approaches to generator design. The measured results convincingly demonstrate the effectiveness practicality of real-time soft x-ray imaging. They also indicate the major changes in technology and approach that must be taken for practical systems to be truly effective

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

    Science.gov (United States)

    Camattari, Riccardo

    2017-09-01

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

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

    CERN Document Server

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

    2001-01-01

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

  8. X-ray mosaic nanotomography of large microorganisms.

    Science.gov (United States)

    Mokso, R; Quaroni, L; Marone, F; Irvine, S; Vila-Comamala, J; Blanke, A; Stampanoni, M

    2012-02-01

    Full-field X-ray microscopy is a valuable tool for 3D observation of biological systems. In the soft X-ray domain organelles can be visualized in individual cells while hard X-ray microscopes excel in imaging of larger complex biological tissue. The field of view of these instruments is typically 10(3) times the spatial resolution. We exploit the assets of the hard X-ray sub-micrometer imaging and extend the standard approach by widening the effective field of view to match the size of the sample. We show that global tomography of biological systems exceeding several times the field of view is feasible also at the nanoscale with moderate radiation dose. We address the performance issues and limitations of the TOMCAT full-field microscope and more generally for Zernike phase contrast imaging. Two biologically relevant systems were investigated. The first being the largest known bacteria (Thiomargarita namibiensis), the second is a small myriapod species (Pauropoda sp.). Both examples illustrate the capacity of the unique, structured condenser based broad-band full-field microscope to access the 3D structural details of biological systems at the nanoscale while avoiding complicated sample preparation, or even keeping the sample environment close to the natural state. Copyright © 2012 Elsevier Inc. All rights reserved.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-08-20

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

  10. An Expanded Rossi X-Ray Timing Explorer Survey of X-Ray Variability in Seyfert 1 Galaxies

    Science.gov (United States)

    Markowitz, A.; Edelson, R.

    2004-12-01

    The first seven years of RXTE monitoring of Seyfert 1 active galactic nuclei have been systematically analyzed to yield five homogeneous samples of 2-12 keV light curves, probing hard X-ray variability on successively longer durations from ~1 day to ~3.5 yr. The 2-10 keV variability on timescales of ~1 day, as probed by ASCA, is included. All sources exhibit stronger X-ray variability toward longer timescales, but the increase is greater for relatively higher luminosity sources. Variability amplitudes are anticorrelated with X-ray luminosity and black hole mass, but amplitudes saturate and become independent of luminosity or black hole mass toward the longest timescales. The data are consistent with the models of power spectral density (PSD) movement described by Markowitz and coworkers and McHardy and coworkers, whereby Seyfert 1 galaxies' variability can be described by a single, universal PSD shape whose break frequency scales with black hole mass. The best-fitting scaling relations between variability timescale, black hole mass, and X-ray luminosity imply an average accretion rate of ~5% of the Eddington limit for the sample. Nearly all sources exhibit stronger variability in the relatively soft 2-4 keV band compared to the 7-12 keV band on all timescales. There are indications that relatively less luminous or less massive sources exhibit a greater degree of spectral variability for a given increase in overall flux.

  11. 13.1 micrometers hard X-ray focusing by a new type monocapillary X-ray optic designed for common laboratory X-ray source

    Science.gov (United States)

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

    2018-04-01

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

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

    International Nuclear Information System (INIS)

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

    1977-01-01

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

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

    Science.gov (United States)

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

    2013-06-11

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

  14. Optimization of a multilayer Laue lens system for a hard x-ray nanoprobe

    International Nuclear Information System (INIS)

    Jiang, Hui; Wang, Hua; Mao, Chengwen; Li, Aiguo; He, Yan; Dong, Zhaohui; Zheng, Yi

    2014-01-01

    Detailed designs of a multilayer Laue lens system for a hard x-ray nanoprobe, including flat and wedged types, are presented, to realize nanoscale point focus and high diffraction efficiency simultaneously. The difficulty of movement and alignment for lens, aperture and sample are considered in the optimization process. Considering the practical requirements of future experiments, the features of the beamline and the structural imperfections, the working energy range, the beam vibration and structural errors are estimated and discussed. (paper)

  15. Sixa-silicon x-ray array

    International Nuclear Information System (INIS)

    Taylor, I.

    1995-01-01

    Full text: The Spectrum-X-Gamma (SRG) satellite is scheduled for launch in 1995-96. Mission objectives include broad and narrow band imaging spectroscopy over a wide range of energies from the EUV through hard X-rays with an emphasis on studying galactic and extragalactic X-ray sources. Timing and moderate resolution spectroscopy can be performed with the solid state spectrometer SIXA (Silicon X-Ray Array), placed on the focal plane of the SODART telescope with total effective area of 1150 cm 2 at 6 keV (for f = 8 in telescope). The detector consists of 19 circular Si(Li) pixels, each with an active diameter of 9.2 min and thickness of 3 min. A radiative cooler will be used to bring the detector to the proper operating temperature (120-130 K). The energy range 0.5-20 keV is divided into 1024 channels of 20 eV size. Photons can be recorded with 30 μs time resolution and 160-200 eV (1-7 keV) energy resolution. Potential observing programmes (for e.g. time-resolved Iron Kα line spectroscopy) include stellar coronae, cataclysmic variables and X-ray binaries; accretion discs and coronae of neutron stars and black hole candidates; supernova remnants, active galactic nuclei and clusters of galaxies. (author)

  16. Real-time digital x-ray subtraction imaging

    International Nuclear Information System (INIS)

    Mistretta, C.A.; Kruger, R.A.; Houk, T.L.

    1982-01-01

    A method of producing visible difference images derived from an x-ray image of an anatomical subject is described. X-rays are directed through the subject, and the image is converted into television fields comprising trains of analog video signals. The analog signals are converted into digital signals, which are then integrated over a predetermined time corresponding to several television fields. Difference video signals are produced by performing a subtraction between the ongoing video signals and the corresponding integrated signals, and are converted into visible television difference images representing changes in the x-ray image

  17. Scientific Challenges for a New X-ray Timing Mission

    International Nuclear Information System (INIS)

    Lamb, Frederick K.

    2004-01-01

    The Rossi X-ray Timing Explorer (RXTE) is an immensely successful mission of exploration and discovery. It has discovered a wealth of rapid X-ray variability phenomena that can be used to address fundamental questions concerning the properties of dense matter and strong gravitational fields as well as important astrophysical questions. It has answered many questions and is likely to answer many more, but to follow up fully on the major discoveries RXTE has made will require a new X-ray timing mission with greater capabilities. This introduction to the present volume describes briefly the advantages of X-ray timing measurements for determining the properties of dense matter and strong gravitational fields, indicates some of the key scientific questions that can be addressed using X-ray timing, and summarizes selected achievements of the RXTE mission. It concludes by citing some of the scientific capabilities a proposed follow-on mission will need in order to be successful

  18. Evolution of Cygnus X-3 through its Radio and X-ray States

    International Nuclear Information System (INIS)

    Szostek, A.; Zdziarski, A. A.; McCollough, M. L.

    2009-01-01

    Based on X-ray spectra and studies of the long-term correlated behavior between radio and soft X-ray, we present a detailed evolution of Cyg X-3 through its radio and X-ray states. We comment on the nature of the hard X-ray tail and possible Simbol X contribution in constraining the models.

  19. Evolution of Cygnus X-3 through its Radio and X-ray States

    Science.gov (United States)

    Szostek, A.; Zdziarski, A. A.; McCollough, M. L.

    2009-05-01

    Based on X-ray spectra and studies of the long-term correlated behavior between radio and soft X-ray, we present a detailed evolution of Cyg X-3 through its radio and X-ray states. We comment on the nature of the hard X-ray tail and possible Simbol X contribution in constraining the models.

  20. Uncooled Radiation Hard Large Area SiC X-ray and EUV Detectors and 2D Arrays, Phase II

    Data.gov (United States)

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

  1. Electronic structure of YbNiX{sub 3} (X =Si, Ge) studied by hard X-ray photoemission spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Hitoshi; Shimada, Kenya; Namatame, Hirofumi [Hiroshima Synchrotron Radiation Center, Hiroshima University, Kagamiyama 2-313, Higashi-Hiroshima 739-0046 (Japan); Utsumi, Yuki [Max-Planck Institute for Chemical Physics of Solids, 01187 Dresden (Germany); Kodama, Junichi; Nagata, Heisuke [Graduate School of Science, Hiroshima University, Kagamiyama 1-3-1, Higashi-Hiroshima 739-8526 (Japan); Avila, Marcos A.; Ribeiro, Raquel A. [Centro de Ciencias Naturais e Humanas, Universidade Federal do ABC, Santo Andre - SP, 09210-580 (Brazil); Umeo, Kazunori [Cryogenics and Instrumental Analysis Division, N-BARD, Hiroshima University, Higashi-Hiroshima 739-8526 (Japan); Takabatake, Toshiro [Department of Quantum Matter, AdSM, Hiroshima University, Higashi-Hiroshima 739-8530 (Japan); Institute for Advanced Materials Research, Hiroshima University, Higashi-Hiroshima 739-8530 (Japan); Mimura, Kojiro; Motonami, Satoru; Anzai, Hiroaki [Graduate School of Engineering, Osaka Prefecture University, Sakai 599-8531 (Japan); Ueda, Shigenori [Synchrotron X-ray Station at SPring-8, National Institute for Materials Science, Hyogo 679-5148 (Japan); Taniguchi, Masaki [Hiroshima Synchrotron Radiation Center, Hiroshima University, Kagamiyama 2-313, Higashi-Hiroshima 739-0046 (Japan); Graduate School of Science, Hiroshima University, Kagamiyama 1-3-1, Higashi-Hiroshima 739-8526 (Japan)

    2015-06-15

    lectronic structure of the Kondo lattices YbNiX{sub 3} (X =Si, Ge) has been investigated by means of hard x-ray photoemission spectroscopy (HAXPES) with hν = 5.95 keV. From the Yb 3d HAXPES spectra, the Yb valence in YbNiSi{sub 3} is estimated to be ∝ 2.92, which is almost temperature-independent. On the other hand, the valence in YbNiGe{sub 3} is estimated to be 2.48 at 300 K, showing significant valence fluctuation, and gradually decreases to 2.41 at 20 K on cooling. The Ni 2p{sub 3/2} and Yb{sup 3+} 4f peaks exhibit opposite energy shifts amounting to ∝ 0.6 eV between YbNiSi{sub 3} and YbNiGe{sub 3}. We propose a simple model for the electronic structure of YbNiX{sub 3} based on the HAXPES results. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  2. Time-resolved x-ray diagnostics

    International Nuclear Information System (INIS)

    Lyons, P.B.

    1981-01-01

    Techniques for time-resolved x-ray diagnostics will be reviewed with emphasis on systems utilizing x-ray diodes or scintillators. System design concerns for high-bandwidth (> 1 GHz) diagnostics will be emphasized. The limitations of a coaxial cable system and a technique for equalizing to improve bandwidth of such a system will be reviewed. Characteristics of new multi-GHz amplifiers will be presented. An example of a complete operational system on the Los Alamos Helios laser will be presented which has a bandwidth near 3 GHz over 38 m of coax. The system includes the cable, an amplifier, an oscilloscope, and a digital camera readout

  3. Hard synchrotron radiation scattering from a nonideal surface grating from multilayer X-ray mirrors

    International Nuclear Information System (INIS)

    Punegov, V.I.; Nesterets, Ya.I.; Mytnichenko, S.V.; Kovalenko, N.V.; Chernov, V.A.

    2003-01-01

    The hard synchrotron radiation scattering from a multilayer surface grating is theoretically and experimentally investigated. The numerical calculations of angular distribution of scattering intensity from X-ray mirror Ni/C are executed with use of recurrence formulae and statistical dynamical theory of diffraction. It is shown, that the essential role in formation of a diffraction pattern plays a diffuse scattering caused by structure imperfection of a multilayer grating [ru

  4. Hard x-ray Morphological and Spectral Studies of the Galactic Center Molecular Cloud SGR B2: Constraining Past SGR A* Flaring Activity

    DEFF Research Database (Denmark)

    Zhang, Shuo; Hailey, Charles J.; Mori, Kaya

    2015-01-01

    In 2013, NuSTAR observed the Sgr B2 region and for the first time resolved its hard X-ray emission on subarcminute scales. Two prominent features are detected above 10 keV:. a newly emerging cloud, G0.66-0.13, and the central 90 '' radius region containing two compact cores, Sgr B2(M) and Sgr B2(N......), surrounded by diffuse emission. It is inconclusive whether the remaining level of Sgr. B2 emission is still decreasing or has reached a constant background level. A decreasing X-ray emission can be best explained by the X-ray reflection nebula scenario, where the cloud reprocesses a past giant outburst from...... Sgr A*. In the X-ray reflection nebula (XRN) scenario, the 3-79 keV Sgr. B2 spectrum allows us to self-consistently test the XRN model using both the Fe K alpha line and the continuum emission. The peak luminosity of the past Sgr A* outburst is constrained to L3-79keV∼5 x 1038 ergs s-1. A newly...

  5. Caliste 64, an innovative CdTe hard X-ray micro-camera

    Energy Technology Data Exchange (ETDEWEB)

    Meuris, A.; Limousin, O.; Pinsard, F.; Le Mer, I. [CEA Saclay, DSM, DAPNIA, Serv. Astrophys., F-91191 Gif sur Yvette (France); Lugiez, F.; Gevin, O.; Delagnes, E. [CEA Saclay, DSM, DAPNIA, Serv. Electron., F-91191 Gif sur Yvette (France); Vassal, M.C.; Soufflet, F.; Bocage, R. [3D-plus Company, F-78532 Buc (France)

    2008-07-01

    A prototype 64 pixel miniature camera has been designed and tested for the Simbol-X hard X-ray observatory to be flown on the joint CNES-ASI space mission in 2014. This device is called Caliste 64. It is a high performance spectro-imager with event time-tagging capability, able to detect photons between 2 keV and 250 keV. Caliste 64 is the assembly of a 1 or 2 min thick CdTe detector mounted on top of a readout module. CdTe detectors equipped with Aluminum Schottky barrier contacts are used because of their very low dark current and excellent spectroscopic performance. Front-end electronics is a stack of four IDeF-X V1.1 ASICs, arranged perpendicular to the detection plane, to read out each pixel independently. The whole camera fits in a 10 * 10 * 20 mm{sup 3} volume and is juxtaposable on its four sides. This allows the device to be used as an elementary unit in a larger array of Caliste 64 cameras. Noise performance resulted in an ENC better than 60 electrons rms in average. The first prototype camera is tested at -10 degrees C with a bias of -400 V. The spectrum summed across the 64 pixels results in a resolution of 697 eV FWHM at 13.9 keV and 808 eV FWFM at 59.54 keV. (authors)

  6. Real-time digital x-ray subtraction imaging

    International Nuclear Information System (INIS)

    Mistretta, C.A.

    1982-01-01

    The invention provides a method of producing visible difference images derived from an X-ray image of an anatomical subject, comprising the steps of directing X-rays through the anatomical subject for producing an image, converting the image into television fields comprising trains of on-going video signals, digitally storing and integrating the on-going video signals over a time interval corresponding to several successive television fields and thereby producing stored and integrated video signals, recovering the video signals from storage and producing integrated video signals, producing video difference signals by performing a subtraction between the integrated video signals and the on-going video signals outside the time interval, and converting the difference signals into visible television difference images representing on-going changes in the X-ray image

  7. Extension of self-seeding to hard X-rays >10 keV as a way to increase user access at the European XFEL

    International Nuclear Information System (INIS)

    Geloni, Gianluca; Kocharyan, Vitali; Saldin, Evgeni

    2011-11-01

    We propose to use the self-seeding scheme with single crystal monochromator at the European X-ray FEL to produce monochromatic, high-power radiation at 16 keV. Based on start to end simulations we show that the FEL power of the transform-limited pulses can reach about 100 GW by exploiting tapering in the tunable-gap baseline undulator. The combination of high photon energy, high peak power, and very narrow bandwidth opens a vast new range of applications, and includes the possibility to considerably increase the user capacity and fully exploit the high repetition rate of the European XFEL. In fact, dealing with monochromatic hard X-ray radiation one may use crystals as deflectors with minimum beam loss. To this end, a photon beam distribution system based on the use of crystals in the Bragg reflection geometry is proposed for future study and possible extension of the baseline facility. They can be repeated a number of times to forman almost complete (one meter scale) ring with an angle of 20 degrees between two neighboring lines. The reflectivity of crystal deflectors can be switched fast enough by flipping the crystals with piezo-electric devices similar to those for X-ray phase retarders at synchrotron radiation facilities. It is then possible to distribute monochromatic hard X-rays among 10 independent instruments, thereby enabling 10 users to work in parallel. The unmatched repetition rate of the European XFEL would be therefore fully exploited. (orig.)

  8. Extension of self-seeding to hard X-rays >10 keV as a way to increase user access at the European XFEL

    Energy Technology Data Exchange (ETDEWEB)

    Geloni, Gianluca [European XFEL GmbH, Hamburg (Germany); Kocharyan, Vitali; Saldin, Evgeni [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2011-11-15

    We propose to use the self-seeding scheme with single crystal monochromator at the European X-ray FEL to produce monochromatic, high-power radiation at 16 keV. Based on start to end simulations we show that the FEL power of the transform-limited pulses can reach about 100 GW by exploiting tapering in the tunable-gap baseline undulator. The combination of high photon energy, high peak power, and very narrow bandwidth opens a vast new range of applications, and includes the possibility to considerably increase the user capacity and fully exploit the high repetition rate of the European XFEL. In fact, dealing with monochromatic hard X-ray radiation one may use crystals as deflectors with minimum beam loss. To this end, a photon beam distribution system based on the use of crystals in the Bragg reflection geometry is proposed for future study and possible extension of the baseline facility. They can be repeated a number of times to forman almost complete (one meter scale) ring with an angle of 20 degrees between two neighboring lines. The reflectivity of crystal deflectors can be switched fast enough by flipping the crystals with piezo-electric devices similar to those for X-ray phase retarders at synchrotron radiation facilities. It is then possible to distribute monochromatic hard X-rays among 10 independent instruments, thereby enabling 10 users to work in parallel. The unmatched repetition rate of the European XFEL would be therefore fully exploited. (orig.)

  9. What Can Simbol-X Do for Gamma-ray Binaries?

    Science.gov (United States)

    Cerutti, B.; Dubus, G.; Henri, G.; Hill, A. B.; Szostek, A.

    2009-05-01

    Gamma-ray binaries have been uncovered as a new class of Galactic objects in the very high energy sky (>100 GeV). The three systems known today have hard X-ray spectra (photon index ~1.5), extended radio emission and a high luminosity in gamma-rays. Recent monitoring campaigns of LSI +61°303 in X-rays have confirmed variability in these systems and revealed a spectral hardening with increasing flux. In a generic one-zone leptonic model, the cooling of relativistic electrons accounts for the main spectral and temporal features observed at high energy. Persistent hard X-ray emission is expected to extend well beyond 10 keV. We explain how Simbol-X will constrain the existing models in connection with Fermi Space Telescope measurements. Because of its unprecedented sensitivity in hard X-rays, Simbol-X will also play a role in the discovery of new gamma-ray binaries, giving new insights into the evolution of compact binaries.

  10. What Can Simbol-X Do for Gamma-ray Binaries?

    International Nuclear Information System (INIS)

    Cerutti, B.; Dubus, G.; Henri, G.; Hill, A. B.; Szostek, A.

    2009-01-01

    Gamma-ray binaries have been uncovered as a new class of Galactic objects in the very high energy sky (>100 GeV). The three systems known today have hard X-ray spectra (photon index ∼1.5), extended radio emission and a high luminosity in gamma-rays. Recent monitoring campaigns of LSI +61 deg. 303 in X-rays have confirmed variability in these systems and revealed a spectral hardening with increasing flux. In a generic one-zone leptonic model, the cooling of relativistic electrons accounts for the main spectral and temporal features observed at high energy. Persistent hard X-ray emission is expected to extend well beyond 10 keV. We explain how Simbol-X will constrain the existing models in connection with Fermi Space Telescope measurements. Because of its unprecedented sensitivity in hard X-rays, Simbol-X will also play a role in the discovery of new gamma-ray binaries, giving new insights into the evolution of compact binaries.

  11. Discovery of Periodic Dips in the Brightest Hard X-Ray Source of M31 with EXTraS

    Science.gov (United States)

    Marelli, Martino; Tiengo, Andrea; De Luca, Andrea; Salvetti, David; Saronni, Luca; Sidoli, Lara; Paizis, Adamantia; Salvaterra, Ruben; Belfiore, Andrea; Israel, Gianluca; Haberl, Frank; D’Agostino, Daniele

    2017-12-01

    We performed a search for eclipsing and dipping sources in the archive of the EXTraS project—a systematic characterization of the temporal behavior of XMM-Newton point sources. We discovered dips in the X-ray light curve of 3XMM J004232.1+411314, which has been recently associated with the hard X-ray source dominating the emission of M31. A systematic analysis of XMM-Newton observations revealed 13 dips in 40 observations (total exposure time of ∼0.8 Ms). Among them, four observations show two dips, separated by ∼4.01 hr. Dip depths and durations are variable. The dips occur only during low-luminosity states ({L}0.2{--12}< 1× {10}38 erg s‑1), while the source reaches {L}0.2{--12}∼ 2.8× {10}38 erg s‑1. We propose that this system is a new dipping low-mass X-ray binary in M31 seen at high inclination (60°–80°) the observed dipping periodicity is the orbital period of the system. A blue HST source within the Chandra error circle is the most likely optical counterpart of the accretion disk. The high luminosity of the system makes it the most luminous (not ULX) dipper known to date.

  12. Real-time x-ray response of biocompatible solution gate AlGaN/GaN high electron mobility transistor devices

    International Nuclear Information System (INIS)

    Hofstetter, Markus; Funk, Maren; Paretzke, Herwig G.; Thalhammer, Stefan; Howgate, John; Sharp, Ian D.; Stutzmann, Martin

    2010-01-01

    We present the real-time x-ray irradiation response of charge and pH sensitive solution gate AlGaN/GaN high electron mobility transistors. The devices show stable and reproducible behavior under and following x-ray radiation, including a linear integrated response with dose into the μGy range. Titration measurements of devices in solution reveal that the linear pH response and sensitivity are not only retained under x-ray irradiation, but an irradiation response could also be measured. Since the devices are biocompatible, and can be simultaneously operated in aggressive fluids and under hard radiation, they are well-suited for both medical radiation dosimetry and biosensing applications.

  13. Steep Hard-X-ray Spectra Indicate Extremely High Accretion Rates in Weak Emission-Line Quasars

    Science.gov (United States)

    Marlar, Andrea; Shemmer, Ohad; Anderson, Scott F.; Brandt, W. Niel; Diamond-Stanic, Aleksandar M.; Fan, Xiaohui; Luo, Bin; Plotkin, Richard; Richards, Gordon T.; Schneider, Donald P.; Wu, Jianfeng

    2018-06-01

    We present XMM-Newton imaging spectroscopy of ten weak emission-line quasars (WLQs) at 0.928 ≤ z ≤ 3.767, six of which are radio quiet and four which are radio intermediate. The new X-ray data enabled us to measure the hard-X-ray power-law photon index (Γ) in each source with relatively high accuracy. These measurements allowed us to confirm previous reports that WLQs have steeper X-ray spectra, therefore indicating higher accretion rates with respect to "typical" quasars. A comparison between the Γ values of our radio-quiet WLQs and those of a carefully-selected, uniform sample of 84 quasars shows that the first are significantly higher, at the ≥ 3σ level. Collectively, the four radio-intermediate WLQs have lower Γ values with respect to the six radio-quiet WLQs, as may be expected if the spectra of the first group are contaminated by X-ray emission from a jet. These results suggest that, in the absence of significant jet emission along our line of sight, WLQs constitute the extreme high end of the accretion rate distribution in quasars. We detect soft excess emission in our lowest-redshift radio-quiet WLQ, in agreement with previous findings suggesting that the prominence of this feature is associated with a high accretion rate. We have not detected signatures of Compton reflection, Fe Kα lines, or strong variability between two X-ray epochs in any of our WLQs.

  14. Hard X-ray Full Field Nano-imaging of Bone and Nanowires at SSRL

    International Nuclear Information System (INIS)

    Andrews, Joy C.; Pianetta, Piero; Meirer, Florian; Chen Jie; Almeida, Eduardo; Meulen, Marjolein C. H. van der; Alwood, Joshua S.; Lee, Cathy; Zhu Jia; Cui Yi

    2010-01-01

    A hard X-ray full field microscope from Xradia Inc. has been installed at SSRL on a 54-pole wiggler end station at beam line 6-2. It has been optimized to operate from 5-14 keV with resolution as high as 30 nm. High quality images are achieved using a vertical beam stabilizer and condenser scanner with high efficiency zone plates with 30 nm outermost zone width. The microscope has been used in Zernike phase contrast, available at 5.4 keV and 8 keV, as well as absorption contrast to image a variety of biological, environmental and materials samples. Calibration of the X-ray attenuation with crystalline apatite enabled quantification of bone density of plate-like and rod-like regions of mouse bone trabecula. 3D tomography of individual lacuna revealed the surrounding cell canaliculi and processes. 3D tomography of chiral branched PbSe nanowires showed orthogonal branches around a central nanowire.

  15. Hard X-ray Full Field Nano-imaging of Bone and Nanowires at SSRL.

    Science.gov (United States)

    Andrews, Joy C; Pianetta, Piero; Meirer, Florian; Chen, Jie; Almeida, Eduardo; van der Meulen, Marjolein C H; Alwood, Joshua S; Lee, Cathy; Zhu, Jia; Cui, Yi

    2010-06-23

    A hard X-ray full field microscope from Xradia Inc. has been installed at SSRL on a 54-pole wiggler end station at beam line 6-2. It has been optimized to operate from 5-14 keV with resolution as high as 30 nm. High quality images are achieved using a vertical beam stabilizer and condenser scanner with high efficiency zone plates with 30 nm outermost zone width. The microscope has been used in Zernike phase contrast, available at 5.4 keV and 8 keV, as well as absorption contrast to image a variety of biological, environmental and materials samples. Calibration of the X-ray attenuation with crystalline apatite enabled quantification of bone density of plate-like and rod-like regions of mouse bone trabecula. 3D tomography of individual lacuna revealed the surrounding cell canaliculi and processes. 3D tomography of chiral branched PbSe nanowires showed orthogonal branches around a central nanowire.

  16. Hard X-ray Full Field Nano-imaging of Bone and Nanowires at SSRL

    Science.gov (United States)

    Andrews, Joy C.; Pianetta, Piero; Meirer, Florian; Chen, Jie; Almeida, Eduardo; van der Meulen, Marjolein C. H.; Alwood, Joshua S.; Lee, Cathy; Zhu, Jia; Cui, Yi

    2010-06-01

    A hard X-ray full field microscope from Xradia Inc. has been installed at SSRL on a 54-pole wiggler end station at beam line 6-2. It has been optimized to operate from 5-14 keV with resolution as high as 30 nm. High quality images are achieved using a vertical beam stabilizer and condenser scanner with high efficiency zone plates with 30 nm outermost zone width. The microscope has been used in Zernike phase contrast, available at 5.4 keV and 8 keV, as well as absorption contrast to image a variety of biological, environmental and materials samples. Calibration of the X-ray attenuation with crystalline apatite enabled quantification of bone density of plate-like and rod-like regions of mouse bone trabecula. 3D tomography of individual lacuna revealed the surrounding cell canaliculi and processes. 3D tomography of chiral branched PbSe nanowires showed orthogonal branches around a central nanowire.

  17. Statistical analysis of fast hard X-ray bursts by SMM observations and microwave bursts by ground-based observations

    Science.gov (United States)

    Li, Chun-Sheng; Jiang, Shu-Ying

    1986-01-01

    In order to understand the relationship between fast hard X-ray bursts (HXRB) and microwave bursts (MWB), data were used from the following publications: NASA Technical Memorandum 84998; Solar Geological Data (1980 to 1983); monthly report of Solar Radio Emission; and NASA and NSF: Solar Geophysical Data (1980 to 1983). For analyzing individual events, the criterion of the same event for HXRB and MWB is determined by peak time difference. There is a good linear correlation between the physical parameter of HXRB and MWB.

  18. X-ray electromagnetic application technology

    International Nuclear Information System (INIS)

    2011-01-01

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

  19. Settling time of dental x-ray tube head after positioning

    International Nuclear Information System (INIS)

    Yun, Suk Ja; Kang, Byung Cheol; Wang, Se Myung; Koh, Chang Sung

    2002-01-01

    The aim of this study was to introduce a method of obtaining the oscillation graphs of the dental x-ray tube heads relative to time using an accelerometer. An Accelerometer, Piezotron type 8704B25 (Kistler Instrument Co., Amherst, NY, USA) was utilized to measure the horizontal oscillation of the x-ray tube head immediately after positioning the tube head for an intraoral radiograph. The signal from the sensor was transferred to a dynamic signal analyzer, which displayed the magnitude of the acceleration on the Y-axis and time lapse on the X-axis. The horizontal oscillation of the tube head was measured relative to time, and the settling time was also determined on the basis of the acceleration graphs for 6 wall type, 5 floor-fixed type, and 4 mobile type dental x-ray machines. The oscillation graphs showed that tube head movement decreased rapidly over time. The settling time varied with x-ray machine types. Wall-type x-ray machines had a settling time of up to 6 seconds, 5 seconds for fixed floor-types, and 11 seconds for the mobile-types. Using an accelerometer, we obtained the oscillation graphs of the dental x-ray tube head relative to time. The oscillation graph with time can guide the operator to decide upon the optimum exposure moment after xray tube head positioning for better radiographic resolution.

  20. Settling time of dental x-ray tube head after positioning

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Suk Ja; Kang, Byung Cheol [Department of Oral and Maxillofacial Radiology, Chonnam National University, Gwangju (Korea, Republic of); Wang, Se Myung; Koh, Chang Sung [Department of Mechatronics, Kwangju Institute of Science and Technology, Gwangju (Korea, Republic of)

    2002-09-15

    The aim of this study was to introduce a method of obtaining the oscillation graphs of the dental x-ray tube heads relative to time using an accelerometer. An Accelerometer, Piezotron type 8704B25 (Kistler Instrument Co., Amherst, NY, USA) was utilized to measure the horizontal oscillation of the x-ray tube head immediately after positioning the tube head for an intraoral radiograph. The signal from the sensor was transferred to a dynamic signal analyzer, which displayed the magnitude of the acceleration on the Y-axis and time lapse on the X-axis. The horizontal oscillation of the tube head was measured relative to time, and the settling time was also determined on the basis of the acceleration graphs for 6 wall type, 5 floor-fixed type, and 4 mobile type dental x-ray machines. The oscillation graphs showed that tube head movement decreased rapidly over time. The settling time varied with x-ray machine types. Wall-type x-ray machines had a settling time of up to 6 seconds, 5 seconds for fixed floor-types, and 11 seconds for the mobile-types. Using an accelerometer, we obtained the oscillation graphs of the dental x-ray tube head relative to time. The oscillation graph with time can guide the operator to decide upon the optimum exposure moment after xray tube head positioning for better radiographic resolution.

  1. Soft X-ray focusing Telescope aboard AstroSat

    DEFF Research Database (Denmark)

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

    2017-01-01

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

  2. Spatially resolving a starburst galaxy at hard X-ray energies: NuSTAR, CHANDRA, AND VLBA observations of NGC 253

    DEFF Research Database (Denmark)

    Wik, D. R.; Lehmer, B. D.; Hornschemeier, A. E.

    2014-01-01

    for the first time. As a follow up to our initial study of its nuclear region, we present the first results concerning the full galaxy from simultaneous NuSTAR, Chandra, and Very Long Baseline Array monitoring of the local starburst galaxy NGC 253. Above ~10 keV, nearly all the emission is concentrated within...... is detected at E > 40 keV. We report upper limits on diffuse inverse Compton emission for a range of spatial models. For the most extended morphologies considered, these hard X-ray constraints disfavor a dominant inverse Compton component to explain the γ-ray emission detected with Fermi and H.E.S.S. If NGC...

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

    Energy Technology Data Exchange (ETDEWEB)

    Haber, Johann Friedrich Albert

    2017-05-15

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

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

    International Nuclear Information System (INIS)

    Haber, Johann Friedrich Albert

    2017-05-01

    This thesis describes quantum optical experiments with X-rays with the aim of reaching the strong-coupling regime of light and matter. We make use of the interaction which arises between resonant matter and X-rays in specially designed thin-film nanostructures which form X-ray cavities. Here, the resonant matter are Tantalum atoms and the Iron isotope "5"7Fe. Both limit the number of modes available to the resonant atoms for interaction, and enhances the interaction strength. Thus we have managed to observe a number of phenomena well-known in quantum optics, which are the building blocks for sophisticated applications in e.g. metrology. Among these are the strong coupling of light and matter and the concurrent exchange of virtual photons, often called Rabi oscillations. Furthermore we have designed and tested a type of cavity hitherto unused in X-ray optics. Finally, we develop a new method for synchrotron Moessbauer spectroscopy, which not only promises to yield high-resolution spectra, but also enables the retrieval of the phase of the scattered light. The results open new avenues for quantum optical experiments with X-rays, particularly with regards to the ongoing development of high-brilliance X-ray free-electron lasers.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-04-04

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

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

    International Nuclear Information System (INIS)

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

    1986-01-01

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

  7. Development of a Hard X-ray Beam Position Monitor for Insertion Device Beams at the APS

    Science.gov (United States)

    Decker, Glenn; Rosenbaum, Gerd; Singh, Om

    2006-11-01

    Long-term pointing stability requirements at the Advanced Photon Source (APS) are very stringent, at the level of 500 nanoradians peak-to-peak or better over a one-week time frame. Conventional rf beam position monitors (BPMs) close to the insertion device source points are incapable of assuring this level of stability, owing to mechanical, thermal, and electronic stability limitations. Insertion device gap-dependent systematic errors associated with the present ultraviolet photon beam position monitors similarly limit their ability to control long-term pointing stability. We report on the development of a new BPM design sensitive only to hard x-rays. Early experimental results will be presented.

  8. Using acoustic levitation in synchrotron based laser pump hard x-ray probe experiments

    Science.gov (United States)

    Hu, Bin; Lerch, Jason; Suthar, Kamlesh; Dichiara, Anthony

    Acoustic levitation provides a platform to trap and hold a small amount of material by using standing pressure waves without a container. The technique has a potential to be used for laser pump x-ray probe experiments; x-ray scattering and laser distortion from the container can be avoided, sample consumption can be minimized, and unwanted chemistry that may occur at the container interface can be avoided. The method has been used at synchrotron sources for studying protein and pharmaceutical solutions using x-ray diffraction (XRD) and small angle x-ray scattering (SAXS). However, pump-probe experiments require homogeneously excited samples, smaller than the absorption depth of the material that must be held stably at the intersection of both the laser and x-ray beams. We discuss 1) the role of oscillations in acoustic levitation and the optimal acoustic trapping conditions for x-ray/laser experiments, 2) opportunities to automate acoustic levitation for fast sample loading and manipulation, and 3) our experimental results using SAXS to monitor laser induced thermal expansion in gold nanoparticles solution. We also performed Finite Element Analysis to optimize the trapping performance and stability of droplets ranging from 0.4 mm to 2 mm. Our early x-ray/laser demonstrated the potential of the technique for time-resolved X-ray science.

  9. On self-consistent ray-tracing and Fokker-Planck modeling of the hard X-ray emission during lower-hybrid current driven in Tokamaks

    International Nuclear Information System (INIS)

    Bizarro, J.P.; Peysson, Y.; Bonoli, P.T.; Carrasco, J.; Dudok de Wit, T.; Fuchs, V.; Hoang, G.T.; Litaudon, X.; Moreau, D.; Pocheau, C.; Shkarofsky, I.P.

    1993-04-01

    A detailed investigation is presented on the ability of combined ray-tracing and Fokker-Planck calculations to predict the hard x-ray (HXR) emission during lower-hybrid (LH) current drive in tokamaks when toroidally induced-ray-stochasticity is important. A large number of rays is used and the electron distribution function is obtained by self-consistently iterating the appropriate LH power deposition and Fokker-Planck calculations. Most of the experimentally observed features of the HXR emission are correctly predicted. It is found that corrections due to radial diffusion of suprathermal electrons and to radiation scattering by the inner wall can be significant

  10. Time-dependent nonequilibrium soft x-ray response during a spin crossover

    Energy Technology Data Exchange (ETDEWEB)

    van Veenendaal, Michel

    2018-03-01

    The rapid development of high-brilliance pulsed X-ray sources with femtosecond time resolution has created a need for a better theoretical understanding of the time-dependent soft-X-ray response of dissipative many-body quantum systems. It is demonstrated how soft-X-ray spectroscopies, such as X-ray absorption and resonant inelastic X-ray scattering at transition-metal L-edges, can provide insight into intersystem crossings, such as a spin crossover. The photoinduced doublet-to-quartet spin crossover on cobalt in Fe-Co Prussian blue analogues is used as an example to demonstrate how the X-ray response is affected by the dissipative nonequilibrium dynamics. The time-dependent soft-X-ray spectra provide a wealth of information that reflect the changes in the nonequilibrium initial state via continuously changing spectral lineshapes that cannot be decomposed into initial photoexcited and final metastable spectra, strong broadenings, a collapse of clear selection rules during the intersystem crossing, strong fluctuations in the isotropic branching ratio in X-ray absorption, and crystal-field collapse/oscillations and strongly time-dependent anti-Stokes processes in RIXS.

  11. Real-time digital X-ray subtraction imaging

    International Nuclear Information System (INIS)

    Mistretta, C.A.; Kruger, R.A.; Houk, T.L.

    1979-01-01

    A diagnostic anatomical X-ray apparatus comprising a converter and a television camera for converting an X-ray image of a subject into a series of television fields of video signals is described in detail. A digital memory system stores and integrates the video signals over a time interval corresponding to a plurality of successive television fields. The integrated video signals are recovered from storage and fed to a digital or analogue subtractor, the resulting output being displayed on a television monitor. Thus the display represents on-going changes in the anatomical X-ray image. In a modification, successive groups of fields are stored and integrated in three memories, cyclically, and subtractions are performed between successive pieces of integrated signals to provide a display of successive alterations in the X-ray image. For investigations of the heart, the integrating interval should be of the order of one cardiac cycle. (author)

  12. Combined use of infrared and hard X-ray microprobes for spectroscopy-based neuroanatomy

    Science.gov (United States)

    Surowka, A. D.; Ziomber, A.; Czyzycki, M.; Migliori, A.; Pieklo, L.; Kasper, K.; Szczerbowska-Boruchowska, M.

    2018-05-01

    Understanding the pathological triggers that affect the structural and physiological integrity of biochemical milieu of neurons is crucial to extend our knowledge on brain disorders, that are in many circumstances hardly treatable. Over recently, by using sophisticated hyperspectral micro-imaging modalities, it has been placed within our reach to get an insight into high fidelity histological details along with corresponding biochemical information in a label-free fashion, without using any additional chemical fixatives. However, in order to push forwards extensive application of these methods in the clinical arena, it is viable to make further iterations in novel data analysis protocols in order to boost their sensitivity. Therefore, in our study we proposed a new combined approach utilizing both benchtop Fourier transform infrared (FTIR) and synchrotron X-ray fluorescence (SR-XRF) micro-spectroscopies coupled with multivariate data clustering using the K-means algorithm for combined molecular and elemental micro-imaging, so that these complimentary analytical tools could be used for delineating between various brain structures based on their biochemical composition. By utilizing mid-IR transmission FTIR experiments, the biochemical composition in terms of lipids, proteins and phosphodiesters became accessible. In turn, the SR-XRF experiment was carried out at the advanced IAEA X-ray spectrometry station at Elettra Sincrotrone Trieste. By measuring in vacuum and by using the primary exciting X-ray beam, monochromatized to 10.5 keV, we took advantage of accessing the characteristic X-ray lines of a variety of elements ranging from carbon to zinc. Herein, we can report that the developed methodology has high specificity for label-free discriminating between lipid- and protein-rich brain tissue areas.

  13. A free-electron laser fourth-generation X-ray source

    International Nuclear Information System (INIS)

    Moncton, D. E.

    1999-01-01

    The field of synchrotrons radiation research has grown rapidly over the last 25 years due to both the push of the accelerator and magnet technology that produces the x-ray beams and the pull of the extraordinary scientific research those beams make possible. Three successive generations of synchrotrons radiation facilities have resulted in beam brilliances 11 to 12 orders of magnitude greater than the standard laboratory x-ray tube. However, greater advances can be easily imagined given the fact that x-ray beams from present-day facilities do not exhibit the coherence or time structure so familiar with the.optical laser. Theoretical work over the last ten years or so has pointed to the possibility of generating hard x-ray beams with laser-like characteristics. The concept is based on self-amplified spontaneous emission in free electron lasers. The use of a superconducting linac could produce a major, cost-effective facility that spans wavelengths from the ultraviolet to the hard x-ray regime, simultaneously servicing large numbers experimenters from a wide range of disciplines. As with each past generation of synchrotron facilities, immense new scientific opportunities from fourth-generation sources

  14. Guiding hard x rays with glass polycapillary fiber

    International Nuclear Information System (INIS)

    Xiao, Q.F.; Ponomarev, I.Y.; Kolomitsev, A.I.; Gibson, D.M.; Dilmanian, F.A.; Nachaliel, E.

    1993-01-01

    X rays can be guided through a polycapillary fiber by multiple total reflections from the smooth channel walls of the fiber. Using monochromatic Synchrotron Radiation at energies of 22 and 44 keV, we measured the efficiency of transmission of x rays through polycapillary fibers with channel diameters of about 13 μm. Efficiencies of 57.3% and 54.5% for 22 keV and 44 keV x rays, respectively, were obtained with a 120-mm-long straight polycapillary fiber aligned with the incident beam. These values are close to the open fraction of the fiber, which is about 60%. In addition, transmission efficiency was measured as a function of the tilt angle between the incident beam and the axis of the fiber. We also measured the transmission efficiency as a function of the deflection angle for a 114-mm-long curved polycapillary fiber. The measurements are compared with a ray-tracing simulation

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

    Science.gov (United States)

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

    2008-10-01

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

  16. A NICER Look at the Aql X-1 Hard State

    Science.gov (United States)

    Bult, Peter; Arzoumanian, Zaven; Cackett, Edward M.; Chakrabarty, Deepto; Gendreau, Keith C.; Guillot, Sebastien; Homan, Jeroen; Jaisawal, Gaurava K.; Keek, Laurens; Kenyon, Steve; Lamb, Frederick K.; Ludlam, Renee; Mahmoodifar, Simin; Markwardt, Craig; Miller, Jon M.; Prigozhin, Gregory; Soong, Yang; Strohmayer, Tod E.; Uttley, Phil

    2018-05-01

    We report on a spectral-timing analysis of the neutron star low-mass X-ray binary (LMXB) Aql X-1 with the Neutron Star Interior Composition Explorer (NICER) on the International Space Station (ISS). Aql X-1 was observed with NICER during a dim outburst in 2017 July, collecting approximately 50 ks of good exposure. The spectral and timing properties of the source correspond to that of a (hard) extreme island state in the atoll classification. We find that the fractional amplitude of the low-frequency (soft thermal emission and the power-law emission. Additionally, we measure hard time lags, indicating the thermal emission at 0.5 keV leads the power-law emission at 10 keV on a timescale of ∼100 ms at 0.3 Hz to ∼10 ms at 3 Hz. Our results demonstrate that the thermal emission in the hard state is intrinsically variable, and is driving the modulation of the higher energy power-law. Interpreting the thermal spectrum as disk emission, we find that our results are consistent with the disk propagation model proposed for accretion onto black holes.

  17. Time response characteristics of X-ray detector system on Silex-Ⅰ laser facility

    International Nuclear Information System (INIS)

    Yi Rongqing; He Xiao'an; Li Hang; Du Huabing; Zhang Haiying; Cao Zhurong

    2013-01-01

    On the Silex-Ⅰ laser facility, the time response characteristics of XRD detector were studied. A laser with a pulse of 32 fs and a wavelength of 800 nm was used to irradiate a plane Au target. X-ray calibrated method of time of exposure X-ray framing camera and time resolution of X-ray streak camera was explored. The time response characteristics of XRD detector and time process of X-ray emission were obtained from experiment. We obtained X-ray calibration method of time of exposure X-ray framing camera and time resolution of X-ray streak camera. (authors)

  18. The one square meter hard X-ray (15-200 KeV) sky survey

    International Nuclear Information System (INIS)

    Ubertini, P.; Bazzano, A.; La Padula, C.D.; Polcaro, V.F.

    1981-01-01

    A long term program was started at I.A.S. since 1979 to perform a survey of the hard X-ray sky using multiwire high pressure Xenon filled Spectroscopic Proportional Counters (SPC). The first payload consisting of two very large area SPC (2,700 cm 2 each) was flown during summer 1980 from the Milo Base (Sicily, Italy). The instrument duplicated to reach 10,800 cm 2 geometric area is expected to fly from northern (1981), southern (1982) and equatorial (1983) bases to perform a deep sky survey

  19. The variable hard x-ray emission of NGC 4945 as observed by NUSTAR

    DEFF Research Database (Denmark)

    Puccetti, Simonetta; Comastri, Andrea; Fiore, Fabrizio

    2014-01-01

    We present a broadband (~0.5-79 keV) spectral and temporal analysis of multiple NuSTAR observations combined with archival Suzaku and Chandra data of NGC 4945, the brightest extragalactic source at 100 keV. We observe hard X-ray (>10 keV) flux and spectral variability, with flux variations of a f...... of a factor of two on timescales of 20 ks. A variable primary continuum dominates the high-energy spectrum (>10 keV) in all states, while the reflected/scattered flux that dominates at E...

  20. X-Ray Timing and Spectral Observations of Galactic Black Hole Candidate XTE J1550--564 During Outburst

    Energy Technology Data Exchange (ETDEWEB)

    Reilly, Kaice T

    2002-12-11

    Soft X-ray transients (SXTs), a sub-class of low-mass X-ray binaries (LMXBs), provide a unique opportunity to test General Relativity and to probe fundamental physics under conditions terrestrially unattainable. SXT outbursts are of great interest because they allow the study of LMXBs under a wide range of accretion rates. The majority of known SXTs contain black holes, therefore SXT outbursts are key to understanding accretion physics around black holes and in active galactic nuclei, which are thought to contain supermassive, M {approx} 10{sup 6} - 10{sup 10} M{circle_dot}, where M{circle_dot} is one solar mass, central compact objects. These compact objects are most likely black holes, which exhibit, on a much larger scale, accretion physics similar to that around black holes in SXTs. In this work, the timing and spectral properties of the SXT and microquasar XTE J1550-564 during outburst are studied. Observations made by the Unconventional Stellar Aspect (USA) Experiment on board the Advanced Research and Global Observation Satellite (ARGOS) are emphasized. USA data show a low-frequency quasi-periodic oscillation (LFQPO) with a centroid frequency that tends to increase with increasing USA flux and a fractional rms amplitude which is correlated with the USA hardness ratio (4-16 keV/1-4 keV). Several high-frequency quasi-periodic oscillations (HFQPOs) were detected by the Rossi X-ray Timing Explorer (RXTE), during periods where the LFQPO is seen to be weakening or not detectable at all. The evolution of the USA hardness ratio with time and source flux is examined. The hardness-intensity diagram shows counterclockwise cyclical evolution and possibly indicates the presence of two independent accretion flows: a geometrically thin, optically thick accretion disk and a hot sub-Keplerian flow.

  1. The size of coronal hard X-ray sources in solar flares: How big are they?

    Science.gov (United States)

    Effenberger, F.; Krucker, S.; Rubio da Costa, F.

    2017-12-01

    Coronal hard X-ray sources are considered to be one of the key signatures of non-thermal particle acceleration and heating during the energy release in solar flares. In some cases, X-ray observations reveal multiple components spatially located near and above the loop top and even further up in the corona. Here, we combine a detailed RHESSI imaging analysis of near-limb solar flares with occulted footpoints and a multi-wavelength study of the flare loop evolution in SDO/AIA. We connect our findings to different current sheet formation and magnetic break-out scenarios and relate it to particle acceleration theory. We find that the upper and usually fainter emission regions can be underestimated in their size due to the majority of flux originating from the lower loops.

  2. NICER observations of MAXI J1820+070 suggest a rapidly-brightening black hole X-ray binary in the hard state

    Science.gov (United States)

    Uttley, P.; Gendreau, K.; Markwardt, C.; Strohmayer, T. E.; Bult, P.; Arzoumanian, Z.; Pottschmidt, K.; Ray, P. S.; Remillard, R.; Pasham, D.; Steiner, J.; Neilsen, J.; Homan, J.; Miller, J. M.; Iwakiri, W.; Fabian, A. C.

    2018-03-01

    NICER observed the new X-ray transient MAXI J1820+070 (ATel #11399, #11400, #11403, #11404, #11406, #11418, #11420, #11421) on multiple occasions from 2018 March 12 to 14. & nbsp;During this time the source brightened rapidly, from a total NICER mean count rate of 880 count/s on March 12 to 2800 count/s by March 14 17:00 & nbsp;UTC, corresponding to a change in 2-10 keV modelled flux (see below) from 1.9E-9 to 5E-9 erg cm-2 s-1. & nbsp; The broadband X-ray spectrum is absorbed by a low column density (fitting the model given below, we obtain 1.5E21 cm-2), in keeping with the low Galactic column in the direction of the source (ATel #11418; Dickey & Lockman, 1990, ARAA, 28, 215; Kalberla et al. 2005, A &A, 440, 775) and consists of a hard power-law component with weak reflection features (broad iron line and narrow 6.4 keV line core) and an additional soft X-ray component.

  3. Hard-X-ray photoelectron spectroscopy of NaxCoO2.yH2O

    International Nuclear Information System (INIS)

    Chainani, A.; Yokoya, T.; Takata, Y.; Tamasaku, K.; Taguchi, M.; Shimojima, T.; Kamakura, N.; Horiba, K.; Tsuda, S.; Shin, S.; Miwa, D.; Nishino, Y.; Ishikawa, T.; Yabashi, M.; Kobayashi, K.; Namatame, H.; Taniguchi, M.; Takada, K.; Sasaki, T.; Sakurai, H.; Takayama-Muromachi, E.

    2005-01-01

    We study the bulk electronic structure of Na x CoO 2 .yH 2 O using Hard X-ray (HX, hν = 5.95KeV) synchrotron photoelectron spectroscopy (PES). The Co 2p core level spectra show well-separated Co 3+ and Co 4+ ions. Cluster calculations suggest low spin Co 3+ and Co 4+ character, and a moderate on-site Coulomb correlation energy U dd ∼3-5.5eV. Photon-dependent valence band PES identifies Co 3d and O 2p derived states, in near agreement with band structure calculations. We discuss the importance of HX-PES for studying correlated transition metal oxides

  4. High Resolution Energetic X-ray Imager (HREXI)

    Science.gov (United States)

    Grindlay, Jonathan

    We propose to design and build the first imaging hard X-ray detector system that incorporates 3D stacking of closely packed detector readouts in finely-spaced imaging arrays with their required data processing and control electronics. In virtually all imaging astronomical detectors, detector readout is done with flex connectors or connections that are not vertical but rather horizontal , requiring loss of focal plane area. For high resolution pixel detectors needed for high speed event-based X-ray imaging, from low energy applications (CMOS) with focusing X-ray telescopes, to hard X-ray applications with pixelated CZT for large area coded aperture telescopes, this new detector development offers great promise. We propose to extend our previous and current APRA supported ProtoEXIST program that has developed the first large area imaging CZT detectors and demonstrated their astrophysical capabilities on two successful balloon flight to a next generation High Resolution Energetic X-ray Imager (HREXI), which would incorporate microvia technology for the first time to connect the readout ASIC on each CZT crystal directly to its control and data processing system. This 3-dimensional stacking of detector and readout/control system means that large area (>2m2) imaging detector planes for a High Resolution Wide-field hard X-ray telescope can be built with initially greatly reduced detector gaps and ultimately with no gaps. This increases detector area, efficiency, and simplicity of detector integration. Thus higher sensitivity wide-field imagers will be possible at lower cost. HREXI will enable a post-Swift NASA mission such as the EREXS concept proposed to PCOS to be conducted as a future MIDEX mission. This mission would conduct a high resolution (<2 arcmin) , broad band (5 200 keV) hard X-ray survey of black holes on all scales with ~10X higher sensitivity than Swift. In the current era of Time Domain Astrophysics, such a survey capability, in conjunction with a n

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

    Indian Academy of Sciences (India)

    2014-07-02

    Jul 2, 2014 ... together. The first refractive lenses for hard X-rays were fabricated and tested by Snigirev et al [3]. ... using silicon and diamond refractive lens materials [4]. Many groups ... PMMA has lower radiation resistance com- pared to ...

  6. X-ray observations of the 5 March 1979. gamma. -burst field

    Energy Technology Data Exchange (ETDEWEB)

    Helfand, D J; Long, K S [Columbia Univ., New York (USA). Columbia Astrophysics Lab.

    1979-12-06

    On 5 March 1979 an extremely intense burst of hard X-rays and ..gamma..-rays was recorded by the nine interplanetary spacecraft of the burst sensor network and localised by time-of-flight determinations to a position coincident with the supernova remnant N49 in the Large Magellanic Cloud. Several times, both before and after the ..gamma..-ray event, this region of the sky was observed with the soft X-ray imaging instruments aboard the Einstein Observatory. Coupled with optical plate material, the soft x-ray data are used here to place severe constraints on models for the origin of this remarkable transient phenomenon.

  7. RAPID SPECTRAL CHANGES OF CYGNUS X-1 IN THE LOW/HARD STATE WITH SUZAKU

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, S.; Makishima, K. [Cosmic Radiation Laboratory, Institute of Physical and Chemical Research (RIKEN), Wako, Saitama 351-0198 (Japan); Negoro, H. [Department of Physics, College of Science and Technology, Nihon University, 1-8 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8308 (Japan); Torii, S.; Noda, H. [Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Mineshige, S. [Department of Astronomy, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan)

    2013-04-20

    Rapid spectral changes in the hard X-ray on a timescale down to {approx}0.1 s are studied by applying a ''shot analysis'' technique to the Suzaku observations of the black hole binary Cygnus X-1, performed on 2008 April 18 during the low/hard state. We successfully obtained the shot profiles, covering 10-200 keV with the Suzaku HXD-PIN and HXD-GSO detector. It is notable that the 100-200 keV shot profile is acquired for the first time owing to the HXD-GSO detector. The intensity changes in a time-symmetric way, though the hardness changes in a time-asymmetric way. When the shot-phase-resolved spectra are quantified with the Compton model, the Compton y-parameter and the electron temperature are found to decrease gradually through the rising phase of the shot, while the optical depth appears to increase. All the parameters return to their time-averaged values immediately within 0.1 s past the shot peak. We have not only confirmed this feature previously found in energies below {approx}60 keV, but also found that the spectral change is more prominent in energies above {approx}100 keV, implying the existence of some instant mechanism for direct entropy production. We discuss possible interpretations of the rapid spectral changes in the hard X-ray band.

  8. Time-resolved materials science opportunities using synchrotron x-ray sources

    International Nuclear Information System (INIS)

    Larson, B.C.; Tischler, J.Z.

    1995-06-01

    The high brightness, high intensity, and pulsed time-structure of synchrotron sources provide new opportunities for time-resolved x-ray diffraction investigations. With third generation synchrotron sources coming on line, high brilliance and high brightness are now available in x-ray beams with the highest flux. In addition to the high average flux, the instantaneous flux available in synchrotron beams is greatly enhanced by the pulsed time structure, which consists of short bursts of x-rays that are separated by ∼tens to hundreds of nanoseconds. Time-resolved one- and two-dimensional position sensitive detection techniques that take advantage of synchrotron radiation for materials science x-ray diffraction investigations are presented, and time resolved materials science applications are discussed in terms of recent diffraction and spectroscopy results and materials research opportunities

  9. Study with the sigma data base of the galactic bulge hard x-ray and gamma-ray sources

    International Nuclear Information System (INIS)

    Vargas, Marielle

    1997-01-01

    The Sigma coded-mask telescope on board the Granat spacecraft produces sky images in the hard X-ray and soft gamma-ray energy domain (30-1300 keV) with an angular resolution of 15 arc minutes. The observations of the 18 Angstroms x 17 Angstroms region around the Galactic Center, performed with Sigma regularly during seven years, allowed the detection of a cluster of 17 sources showing activity beyond 40 ke V. This cluster is identified with the Galactic Bulge and its core coincides with the Galactic Center. Each of these sources reveals matter accretion by a collapse star in binary system. Its nature is determined by the luminosity and the spectral behavior recorded beyond 40 keV. Three accreting black holes show peculiar transient activities and comparable flare luminosities providing a criterion to evaluate distance of other specimens located elsewhere in the Galaxy. No sign of activity has been detected from the very center of the Galaxy where a supermassive black hole would be placed and would accrete the surrounding matter. (author) [fr

  10. Time-of-flight position-sensitive x-ray detection

    International Nuclear Information System (INIS)

    Mowat, J.W.

    1981-01-01

    A new method for recording beam-foil time-of-flight data is described. A stationary, side-window, position-senstive proportional counter, oriented with anode wire parallel to the ion beam, views the decay in flight of excited ions through a Soller slit x-ray collimator. In contrast to the standard method, the exciter foil, placed within or upstream from the field of view, is not moved during the acquisition of a decay curve. Each point on the anode acts like an independent detector seeing a unique segment of the ion beam. The correspondence between the downstream distance at which an ion decays and the position along the anode at which the x-ray is detected makes a pulse-height spectrum of position pulses equivalent to a time-of-flight decay curve. Thus an entire decay curve can now be acquired without moving the foil. Increased efficiency is the most significant improvement over the standard method in which the radiation detector views only a small segment of the flight path at any one time. Experiments using translating foils are subject to a spurious dependence of x-ray intensity on foil position if the foil is non-uniform (or non-uniformly aged) and wobbles as it moves. This effect is eliminated here. Foil aging effects which influence excitation rates and introduce a slowly varying time dependence of the x-ray intensity are automatically normalized by this multichannel technique. The application of this method to metastable x-ray emitting states of low-Z ions are discussed

  11. Hard x-ray contact microscopy with 250 nm spatial resolution using a LiF film detector and a tabletop microsource

    International Nuclear Information System (INIS)

    Almaviva, S.; Bonfigli, F.; Franzini, I.; Lai, A.; Montereali, R. M.; Pelliccia, D.; Cedola, A.; Lagomarsino, S.

    2006-01-01

    An innovative route for deep-submicrometer spatial resolution hard x-ray microscopy with tabletop x-ray source is proposed. A film of lithium fluoride (LiF) was used as imaging detector in contact mode. We present here the x-ray images recorded on LiF films of a Fresnel zone plate with submicrometer gold structures and of an onion cataphyll. The images were read with an optical confocal microscope in fluorescence mode. The measured spatial resolution was about 250 nm, i.e., close to the resolution limit of the confocal microscope. The advantages and drawbacks, and the possible improvements, of this route are discussed

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

    Science.gov (United States)

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

    2016-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Jasper J. van Thor

    2015-01-01

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

  14. Modeling of proton-induced radioactivation background in hard X-ray telescopes: Geant4-based simulation and its demonstration by Hitomi's measurement in a low Earth orbit

    Science.gov (United States)

    Odaka, Hirokazu; Asai, Makoto; Hagino, Kouichi; Koi, Tatsumi; Madejski, Greg; Mizuno, Tsunefumi; Ohno, Masanori; Saito, Shinya; Sato, Tamotsu; Wright, Dennis H.; Enoto, Teruaki; Fukazawa, Yasushi; Hayashi, Katsuhiro; Kataoka, Jun; Katsuta, Junichiro; Kawaharada, Madoka; Kobayashi, Shogo B.; Kokubun, Motohide; Laurent, Philippe; Lebrun, Francois; Limousin, Olivier; Maier, Daniel; Makishima, Kazuo; Mimura, Taketo; Miyake, Katsuma; Mori, Kunishiro; Murakami, Hiroaki; Nakamori, Takeshi; Nakano, Toshio; Nakazawa, Kazuhiro; Noda, Hirofumi; Ohta, Masayuki; Ozaki, Masanobu; Sato, Goro; Sato, Rie; Tajima, Hiroyasu; Takahashi, Hiromitsu; Takahashi, Tadayuki; Takeda, Shin'ichiro; Tanaka, Takaaki; Tanaka, Yasuyuki; Terada, Yukikatsu; Uchiyama, Hideki; Uchiyama, Yasunobu; Watanabe, Shin; Yamaoka, Kazutaka; Yasuda, Tetsuya; Yatsu, Yoichi; Yuasa, Takayuki; Zoglauer, Andreas

    2018-05-01

    Hard X-ray astronomical observatories in orbit suffer from a significant amount of background due to radioactivation induced by cosmic-ray protons and/or geomagnetically trapped protons. Within the framework of a full Monte Carlo simulation, we present modeling of in-orbit instrumental background which is dominated by radioactivation. To reduce the computation time required by straightforward simulations of delayed emissions from activated isotopes, we insert a semi-analytical calculation that converts production probabilities of radioactive isotopes by interaction of the primary protons into decay rates at measurement time of all secondary isotopes. Therefore, our simulation method is separated into three steps: (1) simulation of isotope production, (2) semi-analytical conversion to decay rates, and (3) simulation of decays of the isotopes at measurement time. This method is verified by a simple setup that has a CdTe semiconductor detector, and shows a 100-fold improvement in efficiency over the straightforward simulation. To demonstrate its experimental performance, the simulation framework was tested against data measured with a CdTe sensor in the Hard X-ray Imager onboard the Hitomi X-ray Astronomy Satellite, which was put into a low Earth orbit with an altitude of 570 km and an inclination of 31°, and thus experienced a large amount of irradiation from geomagnetically trapped protons during its passages through the South Atlantic Anomaly. The simulation is able to treat full histories of the proton irradiation and multiple measurement windows. The simulation results agree very well with the measured data, showing that the measured background is well described by the combination of proton-induced radioactivation of the CdTe detector itself and thick Bi4Ge3O12 scintillator shields, leakage of cosmic X-ray background and albedo gamma-ray radiation, and emissions from naturally contaminated isotopes in the detector system.

  15. High resolution hard x-ray microscope on a second generation synchrotron source

    International Nuclear Information System (INIS)

    Tian Yangchao; Li Wenjie; Chen Jie; Liu Longhua; Liu Gang; Tian Jinping; Xiong Ying; Tkachuk, Andrei; Gelb, Jeff; Hsu, George; Yun Wenbing

    2008-01-01

    A full-field, transmission x-ray microscope (TXM) operating in the energy range of 7-11 keV has been installed at the U7A beamline at the National Synchrotron Radiation Laboratory, a second generation synchrotron source operating at 0.8 GeV. Although the photon flux at sample position in the operating energy range is significantly low due to its relatively large emittance, the TXM can get high quality x-ray images with a spatial resolution down to 50 nm with acceptable exposure time. This TXM operates in either absorption or Zernike phase contrast mode with similar resolution. This TXM is a powerful analytical tool for a wide range of scientific areas, especially studies on nanoscale phenomena and structural imaging in biology, materials science, and environmental science. We present here the property of the x-ray source, beamline design, and the operation and key optical components of the x-ray TXM. Plans to improve the throughput of the TXM will be discussed.

  16. Nanofocusing parabolic refractive x-ray lenses

    International Nuclear Information System (INIS)

    Schroer, C.G.; Kuhlmann, M.; Hunger, U.T.; Guenzler, T.F.; Kurapova, O.; Feste, S.; Frehse, F.; Lengeler, B.; Drakopoulos, M.; Somogyi, A.; Simionovici, A.S.; Snigirev, A.; Snigireva, I.; Schug, C.; Schroeder, W.H.

    2003-01-01

    Parabolic refractive x-ray lenses with short focal distance can generate intensive hard x-ray microbeams with lateral extensions in the 100 nm range even at a short distance from a synchrotron radiation source. We have fabricated planar parabolic lenses made of silicon that have a focal distance in the range of a few millimeters at hard x-ray energies. In a crossed geometry, two lenses were used to generate a microbeam with a lateral size of 380 nm by 210 nm at 25 keV in a distance of 42 m from the synchrotron radiation source. Using diamond as the lens material, microbeams with a lateral size down to 20 nm and below are conceivable in the energy range from 10 to 100 keV

  17. A hard X-ray scanning microprobe for fluorescence imaging and microdiffraction at the Advanced Photon Source

    International Nuclear Information System (INIS)

    Cai, L.; Lai, B.; Yun, W.; Ilinski, P.; Legnini, D.; Maser, J.; Rodrigues, W.

    1999-01-01

    A hard x-ray scanning microprobe based on zone plate optics and undulator radiation, in the energy region from 6 to 20 keV, has reached a focal spot size (FWHM) of 0.15 microm (v) x 0.6 microm (h), and a photon flux of 4 x 10 9 photons/sec/0.01%BW. Using a slit 44 meters upstream to create a virtual source, a circular beam spot of 0.15 microm in diameter can be obtained with a photon flux of one order of magnitude less. During fluorescence mapping of trace elements in a single human ovarian cell, the microprobe exhibited an imaging sensitivity for Pt (L a line) of 80 attograms/microm 2 for a count rate of 10 counts per second. The x-ray microprobe has been used to map crystallographic strain and multiquantum well thickness in micro-optoelectronic devices produced with the selective area growth technique

  18. A Shack-Hartmann Sensor for Single-Shot Multi-Contrast Imaging with Hard X-rays

    Directory of Open Access Journals (Sweden)

    Tomy dos Santos Rolo

    2018-05-01

    Full Text Available An array of compound refractive X-ray lenses (CRL with 20 × 20 lenslets, a focal distance of 20cm and a visibility of 0.93 is presented. It can be used as a Shack-Hartmann sensor for hard X-rays (SHARX for wavefront sensing and permits for true single-shot multi-contrast imaging the dynamics of materials with a spatial resolution in the micrometer range, sensitivity on nanosized structures and temporal resolution on the microsecond scale. The object’s absorption and its induced wavefront shift can be assessed simultaneously together with information from diffraction channels. In contrast to the established Hartmann sensors the SHARX has an increased flux efficiency through focusing of the beam rather than blocking parts of it. We investigated the spatiotemporal behavior of a cavitation bubble induced by laser pulses. Furthermore, we validated the SHARX by measuring refraction angles of a single diamond CRL, where we obtained an angular resolution better than 4 μ rad.

  19. Soft excess and orbital evolution studies of X-ray pulsars with BeppoSAX

    International Nuclear Information System (INIS)

    Paul, B.; Naik, S.; Bhatt, N.

    2004-01-01

    We present here a spectral study of two accreting binary X-ray pulsars LMC X-4 and SMC X-1 made with the BeppoSAX observatory. The energy spectrum of both the pulsars in 0.1-10.0 keV band can be described by a model consisting of a hard power-law component, a soft excess and an iron emission line at 6.4 keV. In addition, the power-law component of SMC X-1 also has an exponential cutoff at ∼ 6 keV. Pulse-phase resolved spectroscopy confirms a pulsating nature of the soft spectral component in both the pulsars, with a certain phase offset compared to the hard power-law component. A dissimilar pulse profile of the two spectral components and a phase difference between the pulsating soft and hard spectral components are evidence for their different origins. In another study of an accreting binary X-ray pulsar Her X-1, we have made accurate measurements of new mid-eclipse times from pulse arrival time delays using observations made with the BeppoSAX and RXTE observatories. The new measurements, combined with the earlier reported mid-eclipse times are used to investigate orbital evolution of the binary. The most recent observation indicates deviation from a quadratic trend coincident with an anomalous low X-ray state, observed for the second time in this pulsar

  20. X-Rays from NGC 3256: High-Energy Emission in Starburst Galaxies and Their Contribution to the Cosmic X-Ray Background

    International Nuclear Information System (INIS)

    Moran, Edward C.; Lehnert, Matthew D.; Helfand, David J.

    1999-01-01

    The infrared-luminous galaxy NGC 3256 is a classic example of a merger-induced nuclear starburst system. We find here that it is the most X-ray-luminous star-forming galaxy yet detected (L 0.5-10keV =1.6x10 42 ergs s-1). Long-slit optical spectroscopy and a deep, high-resolution ROSAT X-ray image show that the starburst is driving a ''superwind'' which accounts for ∼20% of the observed soft X-ray emission. Analysis of X-ray spectral data from ASCA indicates this gas has a characteristic temperature of kT≅0.3 keV. Our model for the broadband X-ray emission of NGC 3256 contains two additional components: a warm thermal plasma (kT≅0.8 keV) associated with the central starburst, and a hard power-law component with an energy index of α X ≅0.7. We discuss the energy budget for the two thermal plasmas and find that the input of mechanical energy from the starburst is more than sufficient to sustain the observed level of emission. We also examine possible origins for the power-law component, concluding that neither a buried AGN nor the expected population of high-mass X-ray binaries can account for this emission. Inverse Compton scattering, involving the galaxy's copious flux of infrared photons and the relativistic electrons produced by supernovae, is likely to make a substantial contribution to the hard X-ray flux. Such a model is consistent with the observed radio and IR fluxes and the radio and X-ray spectral indices. We explore the role of X-ray-luminous starbursts in the production of the cosmic X-ray background radiation. The number counts and spectral index distribution of the faint radio source population, thought to be dominated by star-forming galaxies, suggest that a significant fraction of the hard X-ray background could arise from starbursts at moderate redshift. (c) (c) 1999. The American Astronomical Society