WorldWideScience

Sample records for high-brightness x-ray sources

  1. Short Pulse High Brightness X-ray Production with the PLEIADES Thomson Scattering Source

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-07-01

    We describe PLEIADES, a compact, tunable, high-brightness, ultra-short pulse, Thomson x-ray source. The peak brightness of the source is expected to exceed 10{sup 20} photons/s/0.1% bandwidth/mm{sup 2}/mrad{sup 2}. Initial results are reported and compared to theoretical calculations.

  2. Plasmon-enhanced photocathode for high brightness and high repetition rate x-ray sources

    Energy Technology Data Exchange (ETDEWEB)

    Polyakov, Aleksandr; Senft, Christoph; Thompson, K. F.; Feng, J.; Cabrini, S.; Schuck, P. J.; Padmore, Howard; Peppernick, Samuel J.; Hess, Wayne P.

    2013-02-11

    High brightness electron sources are at the heart of anew generation of x-ray sources based on the Free ElectronLaser (FEL) as well as in Energy Recovery Linac (ERL) and Inverse Compton Scattering (ICS) sources.The source of electrons consists of a photoinjector, comprised of a laser-driven photocathode in a high gradient electric field produced by an rf cavity. The function of the rf cavity is to provide a field sufficient for acceleration of electrons to relativistic velocity over a small distance, thus minimizing effects of the space-charge. Even so, the dense electron beam required for high brightness suffers from a space charge field that chirps and reshapes the electron pulse increasing beam emittance and thus reducing the overall brightness. This emittance growth can be avoided if the initial distribution of electrons is pancake shaped, with a semicircular transverse intensity profile. In this case, the electron distribution develops under its space charge field from a pancake into a uniformly filled ellipsoidal beam. This condition, referred to as the blowout regime, requires ultrashort pulses less than 100 fs long and has been successfully demonstrated recently in a high gradient photoinjector.

  3. High-brightness laser plasma soft X-ray source using a double-stream gas puff target irradiated with the Prague Asterix Laser System (PALS)

    Energy Technology Data Exchange (ETDEWEB)

    Fiedorowicz, H.; Bartnik, A.; Juha, L.; Jungwirth, K.; Kralikova, B.; Krasa, J.; Kubat, P.; Pfeifer, M.; Pina, L.; Prchal, P.; Rohlena, K.; Skala, J.; Ullschmied, J.; Horvath, M.; Wawer, J

    2004-01-14

    High brightness laser plasma soft X-ray source based on a recently developed double-stream gas puff target irradiated with 0.5 ns laser pulses with energies up to 700 J from the Prague Asterix Laser System (PALS) is presented. The gas puff target was created by pulsed injection of xenon into a hollow stream of helium using an electromagnetic valve system with the double-nozzle setup. Soft X-ray emission was measured using the transmission grating spectrograph coupled to a CCD camera and the calibrated silicon photodiodes. The absolute soft X-ray production was determined to be 160 J for 540 J of laser energy, giving the soft X-ray conversion efficiency of about 30%. The source has been used in initial experiments on soft X-ray ablation of organic polymers and elemental solids.

  4. Conceptual design of a high-brightness linac for soft X-ray SASE-FEL source

    Energy Technology Data Exchange (ETDEWEB)

    Alesini, D.; Bertolucci, S.; Biagini, M.E.; Biscari, C.; Boni, R.; Boscolo, M.; Castellano, M.; Clozza, A.; Pirro, G.D.G. Di; Drago, A.; Esposito, A.; Ferrario, M. E-mail: massimo.ferrario@lnf.infn.it; Fusco, V.; Gallo, A.; Ghigo, A.; Guiducci, S.; Incurvati, M.; Laurelli, P.; Ligi, C.; Marcellini, F.; Migliorati, M.; Milardi, C.; Palumbo, L.; Pellegrino, L.; Preger, M.; Raimondi, P.; Ricci, R.; Sanelli, C.; Sgamma, F.; Spataro, B.; Serio, M.; Stecchi, A.; Stella, A.; Tazzioli, F.; Vaccarezza, C.; Vescovi, M.; Vicario, C.; Zobov, M.; Acerbi, E.; Alessandria, F.; Barni, D.; Bellomo, G.; Birattari, C.; Bonardi, M.; Boscolo, I.; Bosotti, A.; Broggi, F.; Cialdi, S.; DeMartinis, C.; Giove, D.; Maroli, C.; Michelato, P.; Monaco, L.; Pagani, C.; Petrillo, V.; Pierini, P.; Serafini, L.; Sertore, D.; Volpini, G.; Chiadroni, E.; Felici, G.; Levi, D.; Mastrucci, M.; Mattioli, M.; Medici, G.; Petrarca, G.S.; Catani, L.; Cianchi, A.; D' Angelo, A.; Salvo, R.D.R. Di; Fantini, A.; Moricciani, D.; Schaerf, C.; Bartolini, R.; Ciocci, F.; Dattoli, G.; Doria, A.; Flora, F.; Gallerano, G.P.; Giannessi, L.; Giovenale, E.; Messina, G.; Mezi, L.; Ottaviani, P.L.; Picardi, L.; Quattromini, M.; Renieri, A.; Ronsivalle, C.; Avaldi, L.; Carbone, C.; Cricenti, A.; Pifferi, A.; Perfetti, P.; Prosperi, T.; Albertini, V.R.V. Rossi; Quaresima, C.; Zema, N

    2003-07-11

    FELs based on SASE are believed to be powerful tools to explore the frontiers of basic sciences, from physics to chemistry to biology. Intense R and D programs have started in the USA and Europe in order to understand the SASE physics and to prove the feasibility of these sources. The allocation of considerable resources in the Italian National Research Plan (PNR) brought about the formation of a CNR-ENEA-INFN-University of Roma 'Tor Vergata' study group. A conceptual design study has been developed and possible schemes for linac sources have been investigated, leading to the SPARX proposal. We report in this paper the results of a preliminary start to end simulation concerning one option we are considering based on an S-band normal conducting linac with high-brightness photoinjector integrated in an RF compressor.

  5. First results from the high-brightness x-ray spectroscopy beamline at ALS

    Energy Technology Data Exchange (ETDEWEB)

    Perera, R.C.C.; Ng, W.; Jones, G. [Lawrence Berkeley National Lab., CA (United States)] [and others

    1997-04-01

    Beamline 9.3.1 at the Advanced Light Source (ALS) is a windowless beamline, covering the 1-6 keV photon-energy range, designed to achieve the goal of high brightness at the sample for use in the X-ray Atomic and Molecular Spectroscopy (XAMS) science, surface and interface science, biology and x-ray optical development programs at ALS. X-ray absorption and time of flight photo emission measurements in 2 - 5 keV photon energy in argon along with the flux, resolution, spot size and stability of the beamline will be discussed. Prospects for future XAMS measurements will also be presented.

  6. Optically Levitated Targets as a Source for High Brightness X-rays and a Platform for Mass-Limited Laser-interaction Experiments

    Science.gov (United States)

    Giltrap, Samuel; Stuart, Nick; Robinson, Tim; Armstrong, Chris; Hicks, George; Eardley, Sam; Gumbrell, Ed; Smith, Roland

    2016-10-01

    Here we report on the development of an optical levitation based x-ray and proton source, motivated by the requirement for a debris free, high spatial resolution, and low EMP source for x-ray radiography and proton production. Research at Imperial College has led to the development of a feedback controlled optical levitation trap which is capable of holding both solid (Glass beads) and liquid (silicon based oil) micro-targets ( 3-10um). The optical levitation trap has been successfully fielded in a high-intensity laser interaction experiment at Imperial College London and at the Vulcan Petawatt Laser system at the Rutherford Appleton Laboratory (RAL). Here we report on the results from that RAL run including; an x-ray source size of 10-15um with very good spherical symmetry when compared to wire targets, secondly very low EMP signal from isolated levitated targets (9 times less RF signal than a comparable wire target). At Imperial College we were also able to record an x-ray energy spectrum which produced an electron temperature of 0.48KeV, and performed interferometry of a shock evolving into a blast wave off an optically levitated droplet which allowed us to infer the electron density within the shock front.

  7. High-brightness beamline for x-ray spectroscopy at the ALS

    Energy Technology Data Exchange (ETDEWEB)

    Perera, R.C.C.; Jones, G. [Ernest Orlando Lawrence Berkeley National Lab., CA (United States); Lindle, D.W. [Univ. of Nevada, Las Vegas, NV (United States)

    1997-04-01

    Beamline 9.3.1 at the Advanced Light Source (ALS) is a windowless beamline, covering the 1-6 keV photon-energy range, designed to achieve the goals of high energy resolution, high flux, and high brightness at the sample. When completed later this year, it will be the first ALS monochromatic hard x-ray beamline, and its brightness will be an order of magnitude higher than presently available in this energy range. In addition, it will provide flux and resolution comparable to any other beamline now in operation. To achieve these goals, two technical improvements, relative to existing x-ray beamlines, were incorporated. First, a somewhat novel optical design for x-rays, in which matched toroidal mirrors are positioned before and after the double-crystal monochromator, was adopted. This configuration allows for high resolution by passing a collimated beam through the monochromator, and for high brightness by focusing the ALS source on the sample with unit magnification. Second, a new {open_quotes}Cowan type{close_quotes} double-crystal monochromator based on the design used at NSLS beamline X-24A was developed. The measured mechanical precision of this new monochromator shows significant improvement over existing designs, without using positional feedback available with piezoelectric devices. Such precision is essential because of the high brightness of the radiation and the long distance (12 m) from the source (sample) to the collimating (focusing) mirror. This combination of features will provide a bright, high resolution, and stable x-ray beam for use in the x-ray spectroscopy program at the ALS.

  8. A study on materials of steels by high brightness X-ray

    CERN Document Server

    Tsuzaki, K; Umezawa, O; Hara, T; Takahashi, T; Omura, T; Hayakawa, M; Yamauchi, Y

    2001-01-01

    As the survey study on materials analysis of steels using high brightness X-ray, under aiming to clarify direct experimental facts on deformations, failure phenomena, and metal textures forming at interior portions of bulk materials, feasibility on materials research and development using SPring-8 was surveyed. Its concrete items were summarized to fields shown as follows: 1) acquirement of foundation on synchrotron X-ray, 2) visualization of cracks and artificial cracks in metal bulk samples by using refraction imaging (point light source topography), 3) visualization of the second phase in the metal bulk samples by using refraction imaging, and 4) speciation of carbon elements in steel cords by Moessbauer spectroscopy. Together with clarifying problems more and more by the survey and some experiments, subjects and understandings vacantly considered at standpoints of materials researchers could be arranged and defined. (G.K.)

  9. X-ray lithography source

    Science.gov (United States)

    Piestrup, Melvin A.; Boyers, David G.; Pincus, Cary

    1991-01-01

    A high-intensity, inexpensive X-ray source for X-ray lithography for the production of integrated circuits. Foil stacks are bombarded with a high-energy electron beam of 25 to 250 MeV to produce a flux of soft X-rays of 500 eV to 3 keV. Methods of increasing the total X-ray power and making the cross section of the X-ray beam uniform are described. Methods of obtaining the desired X-ray-beam field size, optimum frequency spectrum and elminating the neutron flux are all described. A method of obtaining a plurality of station operation is also described which makes the process more efficient and economical. The satisfying of these issues makes transition radiation an exellent moderate-priced X-ray source for lithography.

  10. High Brightness Neutron Source for Radiography

    Energy Technology Data Exchange (ETDEWEB)

    Cremer, J. T.; Piestrup, Melvin, A.; Gary, Charles, K.; Harris, Jack, L. Williams, David, J.; Jones, Glenn, E.; Vainionpaa, J. , H.; Fuller, Michael, J.; Rothbart, George, H.; Kwan, J., W.; Ludewigt, B., A.; Gough, R.., A..; Reijonen, Jani; Leung, Ka-Ngo

    2008-12-08

    This research and development program was designed to improve nondestructive evaluation of large mechanical objects by providing both fast and thermal neutron sources for radiography. Neutron radiography permits inspection inside objects that x-rays cannot penetrate and permits imaging of corrosion and cracks in low-density materials. Discovering of fatigue cracks and corrosion in piping without the necessity of insulation removal is possible. Neutron radiography sources can provide for the nondestructive testing interests of commercial and military aircraft, public utilities and petrochemical organizations. Three neutron prototype neutron generators were designed and fabricated based on original research done at the Lawrence Berkeley National Laboratory (LBNL). The research and development of these generators was successfully continued by LBNL and Adelphi Technology Inc. under this STTR. The original design goals of high neutron yield and generator robustness have been achieved, using new technology developed under this grant. In one prototype generator, the fast neutron yield and brightness was roughly 10 times larger than previously marketed neutron generators using the same deuterium-deuterium reaction. In another generator, we integrate a moderator with a fast neutron source, resulting in a high brightness thermal neutron generator. The moderator acts as both conventional moderator and mechanical and electrical support structure for the generator and effectively mimics a nuclear reactor. In addition to the new prototype generators, an entirely new plasma ion source for neutron production was developed. First developed by LBNL, this source uses a spiral antenna to more efficiently couple the RF radiation into the plasma, reducing the required gas pressure so that the generator head can be completely sealed, permitting the possible use of tritium gas. This also permits the generator to use the deuterium-tritium reaction to produce 14-MeV neutrons with increases

  11. CELESTIAL X-RAY SOURCES.

    Science.gov (United States)

    sources, (4) the physical conditions in the pulsating x-ray source in the Crab Nebula , and (5) miscellaneous related topics. A bibliography of all work performed under the contract is given. (Author)

  12. High-brightness X-ray free-electron laser with an optical undulator by pulse shaping.

    Science.gov (United States)

    Chang, Chao; Liang, Jinyang; Hei, Dongwei; Becker, Michael F; Tang, Kelei; Feng, Yiping; Yakimenko, Vitaly; Pellegrini, Claudio; Wu, Juhao

    2013-12-30

    A normal-incident flattop laser with a tapered end is proposed as an optical undulator to achieve a high-gain and high-brightness X-ray free electron laser (FEL). The synchronic interaction of an electron bunch with the normal incident laser is realized by tilting the laser pulse front. The intensity of the flattop laser is kept constant during the interaction time of the electron bunch and the laser along the focal plane of a cylindrical lens. Optical shaping to generate the desired flattop pulse with a tapered end from an original Gaussian pulse distribution is designed and simulated. The flattop laser with a tapered end can enhance the X-ray FEL beyond the exponential growth saturation power by one order to reach 1 Gigawatt as compared to that without a tapered end. The peak brightness can reach 1030 photons/mm2/mrad2/s/0.1% bandwidth, more than 10 orders brighter than the conventional incoherent Thompson Scattering X-ray source.

  13. Real-Time Observation of Laser Heated Metals with High Brightness Monochromatic X-Ray Techniques at Present and Their Future Prospects

    Science.gov (United States)

    Daido, H.; Shobu, T.; Yamada, T.; Yamashita, S.; Sugihara, K.; Nishimura, A.; Muramatsu, T.

    We present the x-ray techniques for characterizing laser heated metals for welding and cutting techniques. At present, with an undulator (70 keV) as well as bending magnet (30 keV) sources at SPring-8 as a probe source, CW 300 W Ytterbium fiber laser irradiates an Aluminum slab as a sample. Simultaneously the x-ray beam probes the sample for real time observation of a molten pool. We observe the convection indicated by the motion of tungsten based particles as a tracer in the molten pool. During the cooling phase, the molten metal is solidified with residual stresses which are affected by the heating and convection processes. In this experiment the time and space resolution are ˜milli-second and several tens of μm, respectively. On the other hand, microscopic short transient phenomena also play a significant role for the quality of a solidified material. For this purpose, we need high energy short pulse x-ray sources. We try to discuss on the capability and limitation of present x-ray sources and the prospect of an ultra high brightness x-ray source as a complementary source for full characterization of the laser heated and cooling processes of metals.

  14. Accelerator x-ray sources

    CERN Document Server

    Talman, Richard

    2007-01-01

    This first book to cover in-depth the generation of x-rays in particle accelerators focuses on electron beams produced by means of the novel Energy Recovery Linac (ERL) technology. The resulting highly brilliant x-rays are at the centre of this monograph, which continues where other books on the market stop. Written primarily for general, high energy and radiation physicists, the systematic treatment adopted by the work makes it equally suitable as an advanced textbook for young researchers.

  15. Soft-X-Ray Projection Lithography Using a High-Repetition-Rate Laser-Induced X-Ray Source for Sub-100 Nanometer Lithography Processes

    NARCIS (Netherlands)

    E. Louis,; F. Bijkerk,; Shmaenok, L.; Voorma, H. J.; van der Wiel, M. J.; Schlatmann, R.; Verhoeven, J.; van der Drift, E. W. J. M.; Romijn, J.; Rousseeuw, B. A. C.; Voss, F.; Desor, R.; Nikolaus, B.

    1993-01-01

    In this paper we present the status of a joint development programme on soft x-ray projection lithography (SXPL) integrating work on high brightness laser plasma sources. fabrication of multilayer x-ray mirrors. and patterning of reflection masks. We are in the process of optimization of a laser-pla

  16. Globular Cluster X-ray Sources

    CERN Document Server

    Verbunt, F

    2004-01-01

    After a brief historical overview we discuss the luminous X-ray sources in globular clusters of our Galaxy. This is followed by an overview of the very luminous X-ray sources studied in globular clusters of 14 other galaxies, and a discussion of their formation and the relation to X-ray sources outside globular clusters. We describe the discovery and classification of low-luminosity X-ray sources, and end the review with some remarks on the formation and evolution of X-ray sources in globular clusters. Observational results are summarized in three tables. Comments are very welcome. Please send them to F.W.M.Verbunt@astro.uu.nl and lewin@mit.edu.

  17. Accelerator-driven X-ray Sources

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-11-09

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

  18. Short X-ray pulses from third-generation light sources.

    Science.gov (United States)

    Stepanov, A G; Hauri, C P

    2016-01-01

    High-brightness X-ray radiation produced by third-generation synchrotron light sources (TGLS) has been used for numerous time-resolved investigations in many different scientific fields. The typical time duration of X-ray pulses delivered by these large-scale machines is about 50-100 ps. A growing number of time-resolved studies would benefit from X-ray pulses with two or three orders of magnitude shorter duration. Here, techniques explored in the past for shorter X-ray pulse emission at TGLS are reviewed and the perspective towards the realisation of picosecond and sub-picosecond X-ray pulses are discussed.

  19. RF Phase Stability and Electron Beam Characterization for the PLEIADES Thomson X-Ray Source

    Energy Technology Data Exchange (ETDEWEB)

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

    2002-10-16

    We report on the performance of an S-band RF photocathode electron gun and accelerator for operation with the PLEIADES Thomson x-ray source at LLNL. To produce picosecond, high brightness x-ray pulses, picosecond timing, terahertz bandwidth diagnostics, and RF phase control are required. Planned optical, RF, x-ray and electron beam measurements to characterize the dependence of electron beam parameters and synchronization on RF phase stability are presented.

  20. Globular cluster x-ray sources.

    Science.gov (United States)

    Pooley, David

    2010-04-20

    Globular clusters and x-ray astronomy have a long and fruitful history. Uhuru and OSO-7 revealed highly luminous (> 10(36) ergs(-1)) x-ray sources in globular clusters, and Einstein and ROSAT revealed a larger population of low-luminosity (luminosity sources were low-mass x-ray binaries in outburst and that they were orders of magnitude more abundant per unit mass in globular clusters than in the rest of the galaxy. However, the low-luminosity sources proved difficult to classify. Many ideas were put forth--low-mass x-ray binaries in quiescence (qLMXBs), cataclysmic variables (CVs), active main-sequence binaries (ABs), and millisecond pulsars (MSPs)--but secure identifications were scarce. In ROSAT observations of 55 clusters, about 25 low-luminosity sources were found. Chandra has now observed over 80 Galactic globular clusters, and these observations have revealed over 1,500 x-ray sources. The superb angular resolution has allowed for many counterpart identifications, providing clues to the nature of this population. It is a heterogeneous mix of qLMXBs, CVs, ABs, and MSPs, and it has been shown that the qLMXBs and CVs are both, in part, overabundant like the luminous LMXBs. The number of x-ray sources in a cluster correlates very well with its encounter frequency. This points to dynamical formation scenarios for the x-ray sources and shows them to be excellent tracers of the complicated internal dynamics. The relation between the encounter frequency and the number of x-ray sources has been used to suggest that we have misunderstood the dynamical states of globular clusters.

  1. Globular cluster x-ray sources

    Science.gov (United States)

    Pooley, David

    2010-01-01

    Globular clusters and x-ray astronomy have a long and fruitful history. Uhuru and OSO-7 revealed highly luminous (> 1036 ergs-1) x-ray sources in globular clusters, and Einstein and ROSAT revealed a larger population of low-luminosity (luminosity sources were low-mass x-ray binaries in outburst and that they were orders of magnitude more abundant per unit mass in globular clusters than in the rest of the galaxy. However, the low-luminosity sources proved difficult to classify. Many ideas were put forth—low-mass x-ray binaries in quiescence (qLMXBs), cataclysmic variables (CVs), active main-sequence binaries (ABs), and millisecond pulsars (MSPs)—but secure identifications were scarce. In ROSAT observations of 55 clusters, about 25 low-luminosity sources were found. Chandra has now observed over 80 Galactic globular clusters, and these observations have revealed over 1,500 x-ray sources. The superb angular resolution has allowed for many counterpart identifications, providing clues to the nature of this population. It is a heterogeneous mix of qLMXBs, CVs, ABs, and MSPs, and it has been shown that the qLMXBs and CVs are both, in part, overabundant like the luminous LMXBs. The number of x-ray sources in a cluster correlates very well with its encounter frequency. This points to dynamical formation scenarios for the x-ray sources and shows them to be excellent tracers of the complicated internal dynamics. The relation between the encounter frequency and the number of x-ray sources has been used to suggest that we have misunderstood the dynamical states of globular clusters. PMID:20404204

  2. Laser ion source for high brightness heavy ion beam

    Science.gov (United States)

    Okamura, M.

    2016-09-01

    A laser ion source is known as a high current high charge state heavy ion source. However we place great emphasis on the capability to realize a high brightness ion source. A laser ion source has a pinpoint small volume where materials are ionized and can achieve quite uniform low temperature ion beam. Those features may enable us to realize very small emittance beams. In 2014, a low charge state high brightness laser ion source was successfully commissioned in Brookhaven National Laboratory. Now most of all the solid based heavy ions are being provided from the laser ion source for regular operation.

  3. LIGHT SOURCE: A simulation study of Tsinghua Thomson scattering X-ray source

    Science.gov (United States)

    Tang, Chuan-Xiang; Li, Ren-Kai; Huang, Wen-Hui; Chen, Huai-Bi; Du, Ying-Chao; Du, Qiang; Du, Tai-Bin; He, Xiao-Zhong; Hua, Jian-Fei; Lin, Yu-Zhen; Qian, Hou-Jun; Shi, Jia-Ru; Xiang, Dao; Yan, Li-Xin; Yu, Pei-Cheng

    2009-06-01

    Thomson scattering X-ray sources are compact and affordable facilities that produce short duration, high brightness X-ray pulses enabling new experimental capacities in ultra-fast science studies, and also medical and industrial applications. Such a facility has been built at the Accelerator Laboratory of Tsinghua University, and upgrade is in progress. In this paper, we present a proposed layout of the upgrade with design parameters by simulation, aiming at high X-ray pulses flux and brightness, and also enabling advanced dynamics studies and applications of the electron beam. Design and construction status of main subsystems are also presented.

  4. X-Ray Emission from Compact Sources

    Energy Technology Data Exchange (ETDEWEB)

    Cominsky, L

    2004-03-23

    This paper presents a review of the physical parameters of neutron stars and black holes that have been derived from X-ray observations. I then explain how these physical parameters can be used to learn about the extreme conditions occurring in regions of strong gravity, and present some recent evidence for relativistic effects seen in these systems. A glossary of commonly used terms and a short tutorial on the names of X-ray sources are also included.

  5. X-ray source for mammography

    Science.gov (United States)

    Logan, Clinton M.

    1994-01-01

    An x-ray source utilizing anode material which shifts the output spectrum to higher energy and thereby obtains higher penetrating ability for screening mammography application, than the currently utilized anode material. The currently used anode material (molybdenum) produces an energy x-ray spectrum of 17.5/19.6 keV, which using the anode material of this invention (e.g. silver, rhodium, and tungsten) the x-ray spectrum would be in the 20-35 keV region. Thus, the anode material of this invention provides for imaging of breasts with higher than average x-ray opacity without increase of the radiation dose, and thus reduces the risk of induced breast cancer due to the radiation dose administered for mammograms.

  6. ECR Ion Source for a High-Brightness Cyclotron

    Science.gov (United States)

    Comeaux, Justin; McIntyre, Peter; Assadi, Saeed

    2011-10-01

    New technology is being developed for high-brightness, high-current cyclotrons with performance benefits for accelerator-driven subcritical fission power, medical isotope production, and proton beam cancer therapy. This paper describes the design for a 65 kV electron cyclotron resonance (ECR) ion source that will provide high-brightness beam for injection into the cyclotron. The ion source is modeled closely upon the one that is used at the Paul Scherrer Institute. Modifications are being made to provide enhanced brightness and compatibility for higher-current operation.

  7. Properties and Applications of Laser Generated X-Ray Sources

    Energy Technology Data Exchange (ETDEWEB)

    Smith, R F; Key, M H

    2002-02-25

    The rapid development of laser technology and related progress in research using lasers is shifting the boundaries where laser based sources are preferred over other light sources particularly in the XUV and x-ray spectral region. Laser based sources have exceptional capability for short pulse and high brightness and with improvements in high repetition rate pulsed operation, such sources are also becoming more interesting for their average power capability. This study presents an evaluation of the current capabilities and near term future potential of laser based light sources and summarizes, for the purpose of comparison, the characteristics and near term prospects of sources based on synchrotron radiation and free electron lasers. Conclusions are drawn on areas where the development of laser based sources is most promising and competitive in terms of applications potential.

  8. X-ray Optics for BES Light Source Facilities

    Energy Technology Data Exchange (ETDEWEB)

    Mills, Dennis [Argonne National Lab. (ANL), Argonne, IL (United States); Padmore, Howard [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lessner, Eliane [Dept. of Energy (DOE), Washington DC (United States). Office of Science

    2013-03-27

    nanolithographic techniques for improved spatial resolution and efficiency of zone plates. Development of large, perfect single crystals of materials other than silicon for use as beam splitters, seeding monochromators, and high-resolution analyzers. Development of improved thin-film deposition methods for fabrication of multilayer Laue lenses and high-spectral-resolution multilayer gratings. Development of supports, actuator technologies, algorithms, and controls to provide fully integrated and robust adaptive X-ray optic systems. Development of fabrication processes for refractive lenses in materials other than silicon. The workshop participants also addressed two important nontechnical areas: our relationship with industry and organization of optics within the light source facilities. Optimization of activities within these two areas could have an important effect on the effectiveness and efficiency of our overall endeavor. These are crosscutting managerial issues that we identified as areas that needed further in-depth study, but they need to be coordinated above the individual facilities. Finally, an issue that cuts across many of the optics improvements listed above is routine access to beamlines that ideally are fully dedicated to optics research and/or development. The success of the BES X-ray user facilities in serving a rapidly increasing user community has led to a squeezing of beam time for vital instrumentation activities. Dedicated development beamlines could be shared with other R&D activities, such as detector programs and novel instrument development. In summary, to meet the challenges of providing the highest-quality X-ray beams for users and to fully utilize the high-brightness sources of today and those that are on the horizon, it will be critical to make strategic investments in X-ray optics R&D. This report can provide guidance and direction for effective use of investments in the field of X-ray optics and potential approaches to develop a better

  9. X-ray Optics for BES Light Source Facilities

    Energy Technology Data Exchange (ETDEWEB)

    Mills, Dennis [Argonne National Lab. (ANL), Argonne, IL (United States); Padmore, Howard [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lessner, Eliane [Dept. of Energy (DOE), Washington DC (United States). Office of Science

    2013-03-27

    nanolithographic techniques for improved spatial resolution and efficiency of zone plates. Development of large, perfect single crystals of materials other than silicon for use as beam splitters, seeding monochromators, and high-resolution analyzers. Development of improved thin-film deposition methods for fabrication of multilayer Laue lenses and high-spectral-resolution multilayer gratings. Development of supports, actuator technologies, algorithms, and controls to provide fully integrated and robust adaptive X-ray optic systems. Development of fabrication processes for refractive lenses in materials other than silicon. The workshop participants also addressed two important nontechnical areas: our relationship with industry and organization of optics within the light source facilities. Optimization of activities within these two areas could have an important effect on the effectiveness and efficiency of our overall endeavor. These are crosscutting managerial issues that we identified as areas that needed further in-depth study, but they need to be coordinated above the individual facilities. Finally, an issue that cuts across many of the optics improvements listed above is routine access to beamlines that ideally are fully dedicated to optics research and/or development. The success of the BES X-ray user facilities in serving a rapidly increasing user community has led to a squeezing of beam time for vital instrumentation activities. Dedicated development beamlines could be shared with other R&D activities, such as detector programs and novel instrument development. In summary, to meet the challenges of providing the highest-quality X-ray beams for users and to fully utilize the high-brightness sources of today and those that are on the horizon, it will be critical to make strategic investments in X-ray optics R&D. This report can provide guidance and direction for effective use of investments in the field of X-ray optics and potential approaches to develop a better

  10. LUX - A recirculating linac-based ultrafast X-ray source

    Energy Technology Data Exchange (ETDEWEB)

    Corlett, J.N.; Barletta, W.A.; DeSantis, S.; Doolittle, L.; Fawley, W.M.; Green, M.A.; Heimann, P.; Leone, S.R.; Lidia, S.; Li, D.; Parmigiani, F.; Ratti, A.; Robinson, K.; Schoenlein, R.; Staples, J.; Wan, W.; Wells, R.; Wilcox, R.; Wolski, A.; Zholents, A.

    2003-08-01

    We describe the design of a proposed source of ultra-fast synchrotron radiation x-ray pulses based on a recirculating superconducting linac, with an integrated array of ultrafast laser systems. The source produces x-ray pulses with duration of 10-50 fs at a 10 kHz repetition rate, with tunability from EUV to hard x-ray regimes, and optimized for the study of ultra-fast dynamics. A high-brightness rf photocathode provides electron bunches. An injector linac accelerates the beam to the 100 MeV range, and is followed by four passes through a 700 MeV recirculating linac. Ultrafast hard x-ray pulses are obtained by a combination of electron bunch manipulation, transverse temporal correlation of the electrons, and x-ray pulse compression. EUV and soft x-ray pulses as short as 10 fs are generated in a harmonic-cascade free electron laser scheme.

  11. Small-animal tomography with a liquid-metal-jet x-ray source

    Science.gov (United States)

    Larsson, D. H.; Lundström, U.; Westermark, U.; Takman, P. A. C.; Burvall, A.; Arsenian Henriksson, M.; Hertz, H. M.

    2012-03-01

    X-ray tomography of small animals is an important tool for medical research. For high-resolution x-ray imaging of few-cm-thick samples such as, e.g., mice, high-brightness x-ray sources with energies in the few-10-keV range are required. In this paper we perform the first small-animal imaging and tomography experiments using liquid-metal-jet-anode x-ray sources. This type of source shows promise to increase the brightness of microfocus x-ray systems, but present sources are typically optimized for an energy of 9 keV. Here we describe the details of a high-brightness 24-keV electron-impact laboratory microfocus x-ray source based on continuous operation of a heated liquid-In/Ga-jet anode. The source normally operates with 40 W of electron-beam power focused onto the metal jet, producing a 7×7 μm2 FWHM x-ray spot. The peak spectral brightness is 4 × 109 photons / ( s × mm2 × mrad2 × 0.1%BW) at the 24.2 keV In Kα line. We use the new In/Ga source and an existing Ga/In/Sn source for high-resolution imaging and tomography of mice.

  12. Modulated method for efficient, narrow-bandwidth, laser Compton X-ray and gamma-ray sources

    Energy Technology Data Exchange (ETDEWEB)

    Barty, Christopher P. J.

    2017-07-11

    A method of x-ray and gamma-ray generation via laser Compton scattering uses the interaction of a specially-formatted, highly modulated, long duration, laser pulse with a high-frequency train of high-brightness electron bunches to both create narrow bandwidth x-ray and gamma-ray sources and significantly increase the laser to Compton photon conversion efficiency.

  13. A simulation study of Tsinghua Thomson scattering X-ray source

    Institute of Scientific and Technical Information of China (English)

    TANG Chuan-Xiang; LI Ren-Kai; HUANG Wen-Hui; CHEN Huai-Bi; DU Ying-Chao; DU Qiang; DU Tai-Bin; HE Xiao-Zhong; HUA Jian-Fei; LIN Yu-Zhen; QIAN Hou-Jun; SHI Jia-Ru; XIANG Dao; YAN Li-Xin; Yu Pei-Cheng

    2009-01-01

    Thomson scattering X-ray sources are compact and afrordable facifities that produce short duration,high brightness X-ray pulses enabling new experimental capacities in ultra-fast science studies,and also medical and industrial applications.Such a facility has been built at the Accelerator Laboratory of Tsinghua University,and upgrade is in progress.In this paper,we present a proposed layout of the upgrade with design parameters by simulation,aiming at high X-ray pulses flux and brightness,and also enabling advanced dynamics studies and applications of the electron beam.Design and construction status of main subsystems are also presented.

  14. Jets from ultraluminous X-ray sources

    Science.gov (United States)

    Urquhart, Ryan

    2017-08-01

    An important set of unsolved problems in accretion physics is whether super-Eddington accretion flows produce jets, what the jet power is (compared with the accretion power), and what the large-scale effect of the jet is on the surrounding gas. Most ultraluminous X-ray sources (ULXs) are super-Eddington stellar-mass compact objects: they provide the best local-Universe test of MHD accretion flow simulations. Observational evidence of collimated jets and fast outflows in ULXs may come in different forms: steady synchrotron radio emission from an unresolved, persistent core; radio flaring associated with discrete ejecta; internal shocks along the jet; hotspots from the jet/ISM interaction; hundred-parsec scale wind/jet-inflated nebulae. We discuss examples of the various cases, use them as proxies to measure the jet power, and compare them with (sub-Eddington) AGN and X-ray binary jets.

  15. Laser-based X-ray and electron source for X-ray fluorescence studies

    Science.gov (United States)

    Valle Brozas, F.; Crego, A.; Roso, L.; Peralta Conde, A.

    2016-08-01

    In this work, we present a modification to conventional X-rays fluorescence using electrons as excitation source and compare it with the traditional X-ray excitation for the study of pigments. For this purpose, we have constructed a laser-based source capable to produce X-rays as well as electrons. Because of the large penetration depth of X-rays, the collected fluorescence signal is a combination of several material layers of the artwork under study. However, electrons are stopped in the first layers, allowing a more superficial analysis. We show that the combination of both excitation sources can provide extremely valuable information about the structure of the artwork.

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

    Science.gov (United States)

    Miaja-Avila, L; O'Neil, G C; Uhlig, J; Cromer, C L; Dowell, M L; Jimenez, R; Hoover, A S; Silverman, K L; Ullom, J N

    2015-03-01

    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 ∼10(6) 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 >10(7) 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.

  17. 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.

  18. Transform-Limited X-Ray Pulse Generation from a High Brightness Self-Amplified Spontaneous Emission Free-Electron Laser

    CERN Document Server

    McNeil, B W J; Dunning, D J

    2012-01-01

    A method to achieve High-Brightness Self-Amplified Spontaneous Emission (HB-SASE) in the Free Electron Laser (FEL) is described. The method uses repeated non-equal electron beam delays to de-localise the collective FEL interaction and break the radiation coherence length dependence on the FEL cooperation length. The method requires no external seeding or photon optics and so is applicable at any wavelength or repetition rate. It is demonstrated using linear theory and numerical simulations that the radiation coherence length can be increased by approximately two orders of magnitude over SASE with a corresponding increase in spectral brightness. Examples are shown of HB-SASE generating transform-limited FEL pulses in the soft X-ray and near transform-limited pulses in the hard X-ray. Such pulses may greatly benefit existing applications and may also open up new areas of scientific research.

  19. Compact X-ray Sources in Nearby Galaxy Nuclei

    CERN Document Server

    Colbert, E J M

    1998-01-01

    We have found compact, near-nuclear X-ray sources in 21 (54\\%) of a complete sample of 39 nearby face-on spiral and elliptical galaxies with available ROSAT HRI data. ROSAT X-ray luminosities (0.2 $-$ 2.4 keV) of these compact X-ray sources are $\\sim$10$^{37}

  20. Obscuring Supersoft X-ray Sources in Stellar Winds

    DEFF Research Database (Denmark)

    Nielsen, Mikkel Thomas Bøje; Dominik, Carsten; Nelemans, Gijs

    2011-01-01

    We investigate the possibility of obscuring supersoft X-ray sources in the winds of companion stars. We derive limits on the amount of circumstellar material needed to fully obscure a 'canonical' supersoft X-ray source in the Large Magellanic Cloud, as observed with the Chandra X-ray Observatory....

  1. Nanomaterial-based x-ray sources

    Science.gov (United States)

    Cole, Matthew T.; Parmee, R. J.; Milne, William I.

    2016-02-01

    Following the recent global excitement and investment in the emerging, and rapidly growing, classes of one and two-dimensional nanomaterials, we here present a perspective on one of the viable applications of such materials: field electron emission based x-ray sources. These devices, which have a notable history in medicine, security, industry and research, to date have almost exclusively incorporated thermionic electron sources. Since the middle of the last century, field emission based cathodes were demonstrated, but it is only recently that they have become practicable. We outline some of the technological achievements of the past two decades, and describe a number of the seminal contributions. We explore the foremost market hurdles hindering their roll-out and broader industrial adoption and summarise the recent progress in miniaturised, pulsed and multi-source devices.

  2. X-Ray Scattering Applications Using Pulsed X-Ray Sources

    Energy Technology Data Exchange (ETDEWEB)

    Larson, B.C.

    1999-05-23

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

  3. Laser-based X-ray and electron source for X-ray fluorescence studies

    CERN Document Server

    Brozas, F Valle; Roso, L; Conde, A Peralta

    2016-01-01

    In this work we present a modification to conventional X-rays fluorescence using electrons as excitation source, and compare it with the traditional X-ray excitation for the study of pigments. For this purpose we have constructed a laser-based source capable to produce X-rays as well as electrons. Because of the large penetration depth of X-rays, the collected fluorescence signal is a combination of several material layers of the artwork under study. However electrons are stopped in the first layers allowing therefore a more superficial analysis. We show that the combination of both excitation sources can provide extremely valuable information about the structure of the artwork.

  4. Focused ion beams using a high-brightness plasma source

    Science.gov (United States)

    Guharay, Samar

    2002-10-01

    High-brightness ion beams, with low energy spread, have merits for many new applications in microelectronics, materials science, and biology. Negative ions are especially attractive for the applications that involve beam-solid interactions. When negative ions strike a surface, especially an electrically isolated surface, the surface charging voltage is limited to few volts [1]. This property can be effectively utilized to circumvent problems due to surface charging, such as device damage and beam defocusing. A compact plasma source, with the capability to deliver either positive or negative ion beams, has been developed. H- beams from this pulsed source showed brightness within an order of magnitude of the value for beams from liquid-metal ion sources. The beam angular intensity is > 40 mAsr-1 and the corresponding energy spread is 1 Acm-2 and a spot size of 100 nm. Such characteristics of focused beam parameters, using a dc source, will immediately open up a large area of new applications. [1] P. N. Guzdar, A. S. Sharma, S. K. Guharay, "Charging of substrates irradiated by particle beams" Appl. Phys. Lett. 71, 3302 (1997). [2] S. K. Guharay, E. Sokolovsky, J. Orloff, "Characteristics of ion beams from a Penning source for focused ion beam applications" J. Vac. Sci Technol. B17, 2779 (1999).

  5. Luminous Binary Supersoft X-Ray Sources

    Science.gov (United States)

    Oliversen, Ronald J. (Technical Monitor); DiStefano, Roseanne

    2005-01-01

    One of the key accomplishments of the two preceding years was our development of an algorithm to select SSSs in external galaxies which have been observed by Chandra or XMM-Newton. By applying this algorithm to data from a number of galaxies, we discovered an extension of the class of SSSs to sources that are somewhat harder (100 - 300 eV, instead of tens of eV), but which are nevertheless much softer than canonical X-ray sources. We call these new sources quasisoft sources (QSSs). During this past year, we have built on and extended this work. We have (1) continued to identify SSSs and QSSs in external galaxies, (2) worked on models for the sources and find that black hole models seem promising for a subset of them, and (3) have studied individual systems, especially M101-ULX1. This special system has been observed as an SSS in its high &ate, with a luminosity in excess of 10(exp 41) erg/s. It has also been observed as a QSS when it is less luminous, and as a hard source in its low state. It is one of the best candidates to be an accreting intermediate-mass black hole. We have several papers in preparation. Below we list papers which are complete, including only new work and papers whose status has changed (e.g., been accepted for publication) since our last report. In addition, our work on QSSs has received some publicity. It was the subject of a Chandra press release and was picked up by several media outlets.

  6. Line-Source Based X-Ray Tomography

    Directory of Open Access Journals (Sweden)

    Deepak Bharkhada

    2009-01-01

    Full Text Available Current computed tomography (CT scanners, including micro-CT scanners, utilize a point x-ray source. As we target higher and higher spatial resolutions, the reduced x-ray focal spot size limits the temporal and contrast resolutions achievable. To overcome this limitation, in this paper we propose to use a line-shaped x-ray source so that many more photons can be generated, given a data acquisition interval. In reference to the simultaneous algebraic reconstruction technique (SART algorithm for image reconstruction from projection data generated by an x-ray point source, here we develop a generalized SART algorithm for image reconstruction from projection data generated by an x-ray line source. Our numerical simulation results demonstrate the feasibility of our novel line-source based x-ray CT approach and the proposed generalized SART algorithm.

  7. Low-luminosity X-ray sources and the Galactic ridge X-ray emission

    CERN Document Server

    Warwick, R S

    2014-01-01

    Using the XMM-Newton Slew Survey, we construct a hard-band selected sample of low-luminosity Galactic X-ray sources. Two source populations are represented, namely coronally-active stars and binaries (ASBs) and cataclysmic variables (CVs), with X-ray luminosities collectively spanning the range 10^(28-34) erg/s (2-10 keV). We derive the 2-10 keV X-ray luminosity function (XLF) and volume emissivity of each population. Scaled to the local stellar mass density, the latter is found to be 1.08 +/- 0.16 x 10^28 erg/s/M and 2.5 +/- 0.6 x 10^27 erg/s/M, for the ASBs and CVs respectively, which in total is a factor 2 higher than previous estimates. We employ the new XLFs to predict the X-ray source counts on the Galactic plane at l = 28.5 deg and show that the result is consistent with current observational constraints. The X-ray emission of faint, unresolved ASBs and CVs can account for a substantial fraction of the Galactic ridge X-ray emission (GRXE). We discuss a model in which roughly 80 per cent of the 6-10 keV...

  8. LIGHT SOURCE: TW Laser system for Thomson scattering X-ray light source at Tsinghua University

    Science.gov (United States)

    Yan, Li-Xm; Du, Ying-Chao; Du, Qiang; Li, Ren-Kai; Hua, Jian-Fei; Huang, Wen-Hui; Tang, Chuan-Xiang

    2009-06-01

    A TW (Tera Watt) laser system based on Ti:sapphire mainly for the Tsinghua Thomson scattering X-ray light source (TTX) is being built. Both UV (ultraviolet) laser pulse for driving the photocathode radio-frequency (RF) gun and the IR (infrared) laser pulse as the electron-beam-scattered-light are provided by the system. Efforts have also been made in laser pulse shaping and laser beam transport to optimize the high-brightness electron beam production by the photocathode RF gun.

  9. Generating coherent soft x-ray pulses in the water window with a high-brightness seeded free-electron laser

    CERN Document Server

    Zhou, Kaishang; Deng, Haixiao; Wang, Dong

    2016-01-01

    We propose a new scheme to generate high-brightness and temporal coherent soft x-ray radiation in a seeded free-electron laser. The proposed scheme is based the coherent harmonic generation (CHG) and superradiant principles. A CHG scheme is first used to generate coherent signal at ultra-high harmonics of the seed. This coherent signal is then amplified by a series of chicane-undulator modules via the fresh bunch and superradiant processes in the following radiator. Using a representative of realistic set of parameters, three-dimensional simulations have been carried out and the simulations results demonstrated that 10 GW-level ultra-short coherent radiation pulses in the water window can be achieved by using the proposed technique.

  10. Generating high-brightness and coherent soft x-ray pulses in the water window with a seeded free-electron laser

    Directory of Open Access Journals (Sweden)

    Kaishang Zhou

    2017-01-01

    Full Text Available We propose a new scheme to generate high-brightness and temporal coherent soft x-ray radiation in a seeded free-electron laser. The proposed scheme is based on the coherent harmonic generation (CHG and superradiant principles. A CHG scheme is first used to generate a coherent signal at ultrahigh harmonics of the seed. This coherent signal is then amplified by a series of chicane-undulator modules via the fresh bunch and superradiant processes in the following radiator. Using a representative of a realistic set of parameters, three-dimensional simulations have been carried out and the simulations results demonstrated that 10 GW-level ultrashort (∼20  fs coherent radiation pulses in the water window can be achieved by using a 1.6 GeV electron beam based on the proposed technique.

  11. Soft x-ray spectromicroscopy development for materials science at the Advanced Light Source

    Energy Technology Data Exchange (ETDEWEB)

    Warwick, T.; Padmore, H. [Lawrence Berkeley National Lab., CA (United States); Ade, H. [North Carolina State Univ., Raleigh, NC (United States); Hitchcock, A.P. [McMaster Univ., Hamilton, Ontario (Canada); Rightor, E.G. [Dow Texas Polymer Center, Freeport, TX (United States); Tonner, B.P. [Univ. of Wisconsin, Milwaukee, WI (United States)

    1996-08-01

    Several third generation synchrotron radiation facilities are now operational and the high brightness of these photon sources offers new opportunities for x-ray microscopy. Well developed synchrotron radiation spectroscopy techniques are being applied in new instruments capable of imaging the surface of a material with a spatial resolution smaller than one micron. There are two aspects to this. One is to further the field of surface science by exploring the effects of spatial variations across a surface on a scale not previously accessible to x-ray measurements. The other is to open up new analytical techniques in materials science using x-rays, on a spatial scale comparable to that of the processes or devices to be studied. The development of the spectromicroscopy program at the Advanced Light Source will employ a variety of instruments, some are already operational. Their development and use will be discussed, and recent results will be presented to illustrate their capabilities.

  12. Compact Optical Counterparts of Ultraluminous X-ray Sources

    CERN Document Server

    Tao, Lian; Grise, Fabien; Kaaret, Philip

    2011-01-01

    Using archival Hubble Space Telescope (HST) imaging data, we report the multiband photometric properties of 13 ultraluminous X-ray sources (ULXs) that have a unique compact optical counterpart. Both magnitude and color variation are detected at time scales of days to years. The optical color, variability, and X-ray to optical flux ratio indicate that the optical emission of most ULXs is dominated by X-ray reprocessing on the disk, similar to that of low mass X-ray binaries. For most sources, the optical spectrum is a power-law, $F_{\

  13. LUX — A Recirculating Linac-based Ultrafast X-ray Source

    Science.gov (United States)

    Corlett, J. N.; Barletta, W. A.; DeSantis, S.; Doolittle, L.; Fawley, W. M.; Green, M. A.; Heimann, P.; Leone, S. R.; Lidia, S.; Li, D.; Parmigiani, F.; Ratti, A.; Robinson, K.; Schoenlein, R.; Staples, J.; Wan, W.; Wells, R.; Wilcox, R.; Wolski, A.; Zholents, A.

    2004-05-01

    We describe the design of a proposed source of ultra-fast synchrotron radiation x-ray pulses based on a recirculating superconducting linac, with an integrated array of ultrafast laser systems. The source produces x-ray pulses with duration of 10-50 fs at a 10 kHz repetition rate, with tunability from EUV to hard x-ray regimes, and optimized for the study of ultra-fast dynamics. A high-brightness rf photocathode provides electron bunches. An injector linac accelerates the beam to the 100 MeV range, and is followed by four passes through a 700 MeV recirculating linac. Ultrafast hard x-ray pulses are obtained by a combination of electron bunch manipulation, transverse temporal correlation of the electrons, and x-ray pulse compression. EUV and soft x-ray pulses as short as 10 fs are generated in a harmonic-cascade free electron laser scheme. We describe the facility major systems and peformance.

  14. Development of a Sub-Picosecond Tunable X-Ray Source at the LLNL Electron Linac

    Energy Technology Data Exchange (ETDEWEB)

    Slaughter, D; Springer, P; Le Sage, G; Crane, J; Ditmire, T; Cowan, T; Anderson, S G; Rosenzweig, J B

    2001-08-31

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

  15. Chandra X-Ray Sources in the LALA Cetus Field

    Science.gov (United States)

    Wang, J. X.; Zheng, Z. Y.; Malhotra, S.; Finkelstein, S. L.; Rhoads, J. E.; Norman, C. A.; Heckman, T. M.

    2007-11-01

    The 174 ks Chandra Advanced CCD Imaging Spectrometer exposure of the Large Area Lyman Alpha Survey (LALA) Cetus field is the second of the two deep Chandra images on LALA fields. In this paper we present the Chandra X-ray sources detected in the Cetus field, along with an analysis of X-ray source counts, stacked X-ray spectrum, and optical identifications. A total of 188 X-ray sources were detected: 174 in the 0.5-7.0 keV band, 154 in the 0.5-2.0 keV band, and 113 in the 2.0-7.0 keV band. The X-ray source counts were derived and compared with LALA field (172 ks exposure). Interestingly, we find consistent hard-band X-ray source density, but (36+/-12)% higher soft-band X-ray source density in Cetus field. The weighted stacked spectrum of the detected X-ray sources can be fitted by a power law with photon index Γ=1.55. Based on the weighted stacked spectrum, we find that the resolved fraction of the X-ray background drops from (72+/-1)% at 0.5-1.0 keV to (63+/-4)% at 6.0-8.0 keV. The unresolved spectrum can be fitted by a power law over the range 0.5-7 keV, with a photon index Γ=1.22. We also present optical counterparts for 154 of the X-ray sources, down to a limiting magnitude of r'=25.9 (Vega), using a deep r'-band image obtained with the MMT. Optical Observations reported here were obtained at the MMT Observatory, a joint facility of the University of Arizona and the Smithsonian Institution.

  16. A Bright Spatially-Coherent Compact X-ray Synchrotron Source

    CERN Document Server

    Kneip, S; Martins, J L; Martins, S F; Bellei, C; Chvykov, V; Dollar, F; Fonseca, R; Huntington, C; Kalintchenko, G; Maksimchuk, A; Mangles, S P D; Matsuoka, T; Nagel, S R; Palmer, C; Schreiber, J; Phuoc, K Ta; Thomas, A G R; Yanovsky, V; Silva, L O; Krushelnick, K; Najmudin, Z

    2009-01-01

    Each successive generation of x-ray machines has opened up new frontiers in science, such as the first radiographs and the determination of the structure of DNA. State-of-the-art x-ray sources can now produce coherent high brightness keV x-rays and promise a new revolution in imaging complex systems on nanometre and femtosecond scales. Despite the demand, only a few dedicated synchrotron facilities exist worldwide, partially due the size and cost of conventional (accelerator) technology. Here we demonstrate the use of a recently developed compact laser-plasma accelerator to produce a well-collimated, spatially-coherent, intrinsically ultrafast source of hard x-rays. This method reduces the size of the synchrotron source from the tens of metres to centimetre scale, accelerating and wiggling a high electron charge simultaneously. This leads to a narrow-energy spread electron beam and x-ray source that is >1000 times brighter than previously reported plasma wiggler and thus has the potential to facilitate a myri...

  17. X-Ray Imaging Crystal Spectrometer for Extended X-Ray Sources

    Energy Technology Data Exchange (ETDEWEB)

    Bitter, Manfred L.; Fraekel, Benjamin; Gorman, James L.; Hill, Kenneth W.; Roquemore, Lane A.; Stodiek, Wolfgang; Goeler, Schweickhard von

    1999-05-01

    Spherically or toroidally curved, double focusing crystals are used in a spectrometer for X-ray diagnostics of an extended X-ray source such as a hot plasma produced in a tokamak fusion experiment to provide spatially and temporally resolved data on plasma parameters such as ion temperature, toroidal and poloidal rotation, electron temperature, impurity ion charge-state distributions, and impurity transport. The imaging properties of these spherically or toroidally curved crystals provide both spectrally and spatially resolved X-ray data from the plasma using only one small spherically or toroidally curved crystal, thus eliminating the requirement for a large array of crystal spectrometers and the need to cross-calibrate the various crystals.

  18. X-ray Radio Correlation In Black Hole Sources

    CERN Document Server

    Rao, A R

    2006-01-01

    We examine the X-ray - radio correlation in Galactic black hole sources. We highlight some of the results which extend the flux-flux relations to sources with very high accretion rates. Some of the recent results indicate that the synchrotron process is unlikely to be the mechanism responsible for the X-ray emission, particularly at high accretion rates. We present a truncated accretion disk scenario and argue that accretion rate and accretion disk geometry ultimately act as a driver of the X-ray - radio correlation. We stress the importance of wide-band X-ray spectral measurements to understand the disk-jet connection and briefly outline some attempts made in the Indian context to build instruments for wide-band X-ray spectroscopy.

  19. 600 eV falcon-linac thomson x-ray source

    Energy Technology Data Exchange (ETDEWEB)

    Crane, J K; LeSage, G P; Ditmire, T; Cross, R; Wharton, K; Moffitt, K; Cowan, T E; Hays, G; Tsai, V; Anderson, G; Shuttlesworth, R; Springer, P

    2000-12-15

    The advent of 3rd generation light sources such as the Advanced Light Source (ALS) at LBL, and the Advanced Photon Source at Argonne, have produced a revolution in x-ray probing of dense matter during the past decade. These machines use electron-synchrotrons in conjunction with undulator stages to produce 100 psec x-ray pulses with photon energies of several kiloelectronvolts (keV). The applications for x-ray probing of matter are numerous and diverse with experiments in medicine and biology, semiconductors and materials science, and plasma and solid state physics. In spite of the success of the 3rd generation light sources there is strong motivation to push the capabilities of x-ray probing into new realms, requiring shorter pulses, higher brightness and harder x-rays. A 4th generation light source, the Linac Coherent Light Source (LCLS), is being considered at the Stanford Linear Accelerator [1]. The LCLS will produce multi-kilovolt x-rays of subpicosecond duration that are 10 orders of magnitude brighter than today's 3rd generation light sources.[1] Although the LCLS will provide unprecedented capability for performing time-resolved x-ray probing of ultrafast phenomena at solid densities, this machine will not be completed for many years. In the meantime there is a serious need for an ultrashort-pulse, high-brightness, hard x-ray source that is capable of probing deep into high-Z solid materials to measure dynamic effects that occur on picosecond time scales. Such an instrument would be ideal for probing the effects of shock propagation in solids using Bragg and Laue diffraction. These techniques can be used to look at phase transitions, melting and recrystallization, and the propagation of defects and dislocations well below the surface in solid materials. [2] These types of dynamic phenomena undermine the mechanical properties of metals and are of general interest in solid state physics, materials science, metallurgy, and have specific relevance to

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

    Science.gov (United States)

    Lewin, W. H. G.; Joss, P. C.

    1981-01-01

    An attempt is made to distill from observational and theoretical information on the galactic bulge X-ray sources in general, and on the X-ray burst sources in particular, those aspects which seem to have the greatest relevance to the understanding of these sources. Galactic bulge sources appear to be collapsed objects of roughly solar mass, in most cases neutron stars, which are accreting matter from low-mass stellar companions. Type I bursts seem to result from thermonuclear flashes in the surface layers of some of these neutron stars, while the type II bursts from the Rapid Burster are almost certainly due to an instability in the accretion flow onto a neutron star. It is concluded that the studies cited offer a new and powerful observational handle on the fundamental properties of neutron stars and of the interacting binary systems in which they are often contained.

  1. Ultrafast X-ray Science at the Sub-Picosecond Pulse Source

    Energy Technology Data Exchange (ETDEWEB)

    Gaffney, Kelly J.; /SLAC, SSRL

    2005-09-30

    The ultrafast, high brightness x-ray free electron laser (XFEL) sources of the future have the potential to revolutionize the study of time dependent phenomena in the natural sciences. These linear accelerator (linac) sources will generate femtosecond (fs) x-ray pulses with peak flux comparable to conventional lasers, and far exceeding all other x-ray sources. The Stanford Linear Accelerator Center (SLAC) has pioneered the development of linac science and technology for decades, and since 2000 SLAC and the Stanford Synchrotron Radiation Laboratory (SSRL) have focused on the development of linac based ultrafast electron and x-ray sources. This development effort has led to the creation of a new x-ray source, called the Sub-Picosecond Pulse Source (SPPS), which became operational in 2003 [1]. The SPPS represents the first step toward the world's first hard x-ray free electron laser (XFEL), the Linac Coherent Light Source (LCLS), due to begin operation at SLAC in 2009. The SPPS relies on the same linac-based acceleration and electron bunch compression schemes that will be used at the LCLS to generate ultrashort, ultrahigh peak brightness electron bunches [2]. This involves creating an energy chirp on the electron bunch during acceleration and subsequent compression of the bunch in a series of energy-dispersive magnetic chicanes to create 80 fs electron pulses. The SPPS has provided an excellent opportunity to demonstrate the viability of these electron bunch compression schemes and to pursue goals relevant to the utilization and validation of XFEL light sources.

  2. Automated classification of Chandra X-ray sources

    Science.gov (United States)

    Brehm, Derek; Kargaltsev, O.; Rangelov, B.; Volkov, I.; Pavlov, G. G.

    2014-01-01

    With the advent of the latest generation X-ray telescopes there has been a major influx of data associated with the detection of hundreds of thousands X-ray sources. As one can rarely tell a source type from its X-ray properties alone, the full potential of the X-ray catalogs can only be unlocked by correlating multiwavelength (MW) properties via cross-identification with other surveys. However, one would spend an enormous amount of time classifying these objects by their physical nature if the classification was to be done on a source-by-source basis by humans. Therefore, we are using a supervised learning algorithm to classify sources detected by the Chandra X-ray Observatory. The classifications are based on a training dataset which currently includes about 7,000 X-ray sources of known nature (main sequence stars, Wolf-Rayet stars, young stars, active galactic nuclei, low mass X-ray binaries, high mass x-ray binaries, and neutron stars). For each source, the training dataset includes up to 24 multiwavelength properties. The efficiency and accuracy of the classification is verified by dividing the training dataset in two and performing cross-validation. The results are also inspected by plotting source properties in 2D slices of the parameter space. As an application of our automated procedure we classified unidentified sources in the supernova remnant (SNR) G352.7-0.1, in the field of HESS J1809-193, and in part of the Chandra Source Catalog 1.0. We present the results of the verification tests and the classification results. This research was partially supported by NASA/SAO grant AR3-14017X.

  3. Miniature X-ray Source for Planetary Exploration Instruments Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of the proposed work is to develop a rugged, low power, passively cooled X-Ray source that is compatible with miniaturized XRD systems. The XRD...

  4. X-ray Measurements of Black Hole X-ray Binary Source GRS 1915+105 and the Evolution of Hard X-ray Spectrum

    Indian Academy of Sciences (India)

    R. K. Manchanda

    2000-06-01

    We report the spectral measurement of GRS 1915+105 in the hard X-ray energy band of 20-140keV. The observations were made on March 30th, 1997 during a quiescent phase of the source. We discuss the mechanism of emission of hard X-ray photons and the evolution of the spectrum by comparing the data with earlier measurements and an axiomatic model for the X-ray source.

  5. Development and characterization of a tunable ultrafast X-ray source via inverse-Compton-scattering

    Energy Technology Data Exchange (ETDEWEB)

    Jochmann, Axel

    2014-07-01

    Ultrashort, nearly monochromatic hard X-ray pulses enrich the understanding of the dynamics and function of matter, e.g., the motion of atomic structures associated with ultrafast phase transitions, structural dynamics and (bio)chemical reactions. Inverse Compton backscattering of intense laser pulses from relativistic electrons not only allows for the generation of bright X-ray pulses which can be used in a pump-probe experiment, but also for the investigation of the electron beam dynamics at the interaction point. The focus of this PhD work lies on the detailed understanding of the kinematics during the interaction of the relativistic electron bunch and the laser pulse in order to quantify the influence of various experiment parameters on the emitted X-ray radiation. The experiment was conducted at the ELBE center for high power radiation sources using the ELBE superconducting linear accelerator and the DRACO Ti:sapphire laser system. The combination of both these state-of-the-art apparatuses guaranteed the control and stability of the interacting beam parameters throughout the measurement. The emitted X-ray spectra were detected with a pixelated detector of 1024 by 256 elements (each 26μm by 26μm) to achieve an unprecedented spatial and energy resolution for a full characterization of the emitted spectrum to reveal parameter influences and correlations of both interacting beams. In this work the influence of the electron beam energy, electron beam emittance, the laser bandwidth and the energy-anglecorrelation on the spectra of the backscattered X-rays is quantified. A rigorous statistical analysis comparing experimental data to ab-initio 3D simulations enabled, e.g., the extraction of the angular distribution of electrons with 1.5% accuracy and, in total, provides predictive capability for the future high brightness hard X-ray source PHOENIX (Photon electron collider for Narrow bandwidth Intense X-rays) and potential all optical gamma-ray sources. The results

  6. A 24 keV liquid-metal-jet x-ray source for biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Larsson, D. H.; Takman, P. A. C.; Lundstroem, U.; Burvall, A.; Hertz, H. M. [Biomedical and X-Ray Physics, Department of Applied Physics, Royal Institute of Technology/Albanova, SE-10691 Stockholm (Sweden)

    2011-12-15

    We present a high-brightness 24-keV electron-impact microfocus x-ray source based on continuous operation of a heated liquid-indium/gallium-jet anode. The 30-70 W electron beam is magnetically focused onto the jet, producing a circular 7-13 {mu}m full width half maximum x-ray spot. The measured spectral brightness at the 24.2 keV In K{sub {alpha}} line is 3 x 10{sup 9} photons/(s x mm{sup 2}x mrad{sup 2}x 0.1% BW) at 30 W electron-beam power. The high photon energy compared to existing liquid-metal-jet sources increases the penetration depth and allows imaging of thicker samples. The applicability of the source in the biomedical field is demonstrated by high-resolution imaging of a mammography phantom and a phase-contrast angiography phantom.

  7. Full spatially coherent multiturn ERL x-ray source (MARS) based on two linacs

    Science.gov (United States)

    Getmanov, Ya V.; Kulipanov, G. N.; Shevchenko, O. A.; Skrinsky, A. N.; Tribendis, A. G.; Volkov, V. N.; Vinokurov, N. A.

    2013-03-01

    Multiturn energy recovery linacs (ERL) looks very promising for making ERLs less expensive and more flexible, but have serious intrinsic problems. Today, only one multiturn ERL exists. This Novosibirsk ERL operates with four orbit recuperation scheme. The conception of Multiturn Accelerator-recuperator Radiation Source (MARS) was proposed in 1997 by G.N. Kulipanov, A.N. Skrinsky and N.A. Vinokurov. The use of the two-linac ERL (D. Douglas, 2001) makes multiturn operation much easier. The feasibility study for such ERL-based high brightness x-ray source is presented.

  8. ROLE OF DIAMOND SECONDARY EMITTERS IN HIGH BRIGHTNESS ELECTRON SOURCES.

    Energy Technology Data Exchange (ETDEWEB)

    RAO, T.; BEN-ZVI, I.; BURRILL, A.; CHANG, X.; GRIMES, J.; RANK, J.; SEGALOV, Z.; SMEDLEY, J.

    2005-09-20

    In this paper we explore the possibility of using diamond secondary emitter in a high average current electron injector to amplify the current from the photocathode and to isolate the cathode and the injector from each other to increase the life time of the cathode and preserve the performance of the injector. Secondary electron yield of 225 and current density of 0.8 a/cm{sup 2} have been measured in the transmission mode from type 2 a natural diamond. Although the diamond will be heated during normal operation in the injector, calculations indicate that by cryogenically cooling the diamond, the temperature gradient along the diamond can be maintained within the acceptable range. The electron energy and temporal distributions are expected to be narrow from this device resulting in high brightness beams. Plans are underway to measure the SEY in emission mode, fabricate photocathode-diamond capsule and test diamond and capsule in superconducting RF injector.

  9. Chandra Multiwavelength Project X-ray Point Source Catalog

    CERN Document Server

    Kim, M; Wilkes, B J; Green, P J; Kim, E; Anderson, C S; Barkhouse, W A; Evans, N R; Ivezic, Z; Karovska, M; Kashyap, V L; Lee, M G; Maksym, P; Mossman, A E; Silverman, J D; Tananbaum, H D; Kim, Minsun; Kim, Dong-Woo; Wilkes, Belinda J.; Green, Paul J.; Kim, Eunhyeuk; Anderson, Craig S.; Barkhouse, Wayne A.; Evans, Nancy R.; Ivezic, Zeljko; Karovska, Margarita; Kashyap, Vinay L.; Lee, Myung Gyoon; Maksym, Peter; Mossman, Amy E.; Silverman, John D.; Tananbaum, Harvey D.

    2006-01-01

    We present the Chandra Multiwavelength Project (ChaMP) X-ray point source catalog with ~6,800 X-ray sources detected in 149 Chandra observations covering \\~10 deg^2. The full ChaMP catalog sample is seven times larger than the initial published ChaMP catalog. The exposure time of the fields in our sample ranges from 0.9 to 124 ksec, corresponding to a deepest X-ray flux limit of f_{0.5-8.0} = 9 x 10^{-16} erg/cm2/sec. The ChaMP X-ray data have been uniformly reduced and analyzed with ChaMP-specific pipelines, and then carefully validated by visual inspection. The ChaMP catalog includes X-ray photometric data in 8 different energy bands as well as X-ray spectral hardness ratios and colors. To best utilize the ChaMP catalog, we also present the source reliability, detection probability and positional uncertainty. To quantitatively assess those parameters, we performed extensive simulations. In particular, we present a set of empirical equations: the flux limit as a function of effective exposure time, and the p...

  10. TW Laser system for Thomson scattering X-ray light source at Tsinghua University

    Institute of Scientific and Technical Information of China (English)

    YAN Li-Xin; DU Ying-Chao; DU Qiang; LI Ren-Kai; HUA Jian-Fei; HUANG Wen-Hui; TANG Chuan-Xiang

    2009-01-01

    A TW(Tera Watt)laser system based on Ti:sapphire mainly for the Tsinghua Thomson scattering X-ray light source(TTX)is being built.Both UV(ultraviolet)laser pulse for driving the photocathode radiofrequency(RF)gun and the IR(infrared)laser pulse as the electron-beam-scattered-light are provided by the system.Efforts have also been made in laser pulse shaping and laser beam transport to optimize the high-brightness electron beam production by the photocathode RF gun.

  11. Results from the Daresbury Compton backscattering X-ray source

    Energy Technology Data Exchange (ETDEWEB)

    Laundy, D. [STFC Daresbury Laboratory, Daresbury, Warrington, Cheshire, WA4 4AD (United Kingdom); Priebe, G. [Max Born Institute, Max-Born-Strasse 2A, 12489 Berlin, DE (Germany); Jamison, S.P. [STFC Daresbury Laboratory, Daresbury, Warrington, Cheshire, WA4 4AD (United Kingdom); Graham, D.M. [The Photon Science Institute, The University of Manchester, Manchester M13 9PL (United Kingdom); Phillips, P.J. [STFC Rutherford Appleton Laboratory, Chilton, Didcot, OX11 0QX (United Kingdom); Smith, S.L.; Saveliev, Y. [STFC Daresbury Laboratory, Daresbury, Warrington, Cheshire, WA4 4AD (United Kingdom); Vassilev, S. [The University of Nottingham, Nottingham, NG7 2RD (United Kingdom); Seddon, E.A., E-mail: elaine.seddon@stfc.ac.uk [The Photon Science Institute, The University of Manchester, Manchester M13 9PL (United Kingdom)

    2012-10-11

    The Daresbury Compton Backscattering X-ray Source uses a high power Ti Sapphire laser interacting in head on geometry with electron bunches in the ALICE energy recovery linear accelerator. X-ray photons with peak energy of 21 keV were generated with the accelerator operating at an energy of 29.6 MeV. The spatial profile of the X-rays emitted near the electron beam axis was measured. The characteristics of the X-ray yield measured as a function of relative timing between the laser pulse and the interacting electron bunch was found to be consistent with the modelled intensity behaviour using measured electron and laser beam parameters.

  12. Development of a new X-ray source using backscattered X-ray with the use of a cold cathode

    Science.gov (United States)

    Tanizawa, Keisuke; Sekiya, Tetsuo; Ohshio, Shigeo; Akasaka, Hiroki; Saitoh, Hidetoshi

    2011-02-01

    The development of an intense X-ray source using backscattered X-ray produced using an advanced electrode configuration is described. The electrodes were composed of field emitters deposited on a wire mounted on a perforated plate as the cathode and a copper plate as the anode. Electrons from these emitters collided with the copper plate and X-ray was generated at collision points. The backscattered X-ray in the direction normal to the electron trajectory through a hole in the anode escaped from the vacuum chamber through a beryllium window. Continuous and characteristic X-rays were detected at an applied voltage lower than that of a conventional X-ray source from 3.0 to 9.4 kV, respectively. Moreover, the X-ray dosage measured with a survey meter reached 0.95 mSv/h at 5.0 kV of applied voltage. The transmission images of three types of material used as an X-ray source for the X-ray imaging system indicate three advantages; low power consumption, focal point controllable by adjusting applied voltage, and photographable motion picture of X-ray transmission.

  13. Optical Counterparts of Ultra Luminous X-ray Sources

    CERN Document Server

    Gutíerrez, C M

    2006-01-01

    We present optical identification and characterization of counterparts of four objects previously catalogued as ultra-luminous X-ray sources. The objects were selected from the Colbert & Ptak (2002) catalogue. The optical counterparts are identified as point-like objects with magnitudes in the range \\~17-19. The optical spectra of three of the sources (IXO 32, 37 and 40) show the presence of emission lines typical of quasars. The position of these lines allows a precise estimation of their redshifts (2.769, 0.567 and 0.789 for IXO 32, 37 and 40 respectively). The fourth X-ray source, IXO35, is associated with a red object that has a spectrum typical of an M star in our Galaxy. These identifications are useful for building clean samples of ULX sources, selecting suitable targets for future observations and performing statistical studies on the different populations of X-ray sources.

  14. Optimized Volumetric Scanning for X-Ray Array Sources

    Energy Technology Data Exchange (ETDEWEB)

    Lehman, S K; Foudray, A M; Wang, A; Kallman, J S; Martz, H

    2009-09-29

    Non-destructive evaluation (NDE) is the science and technology of determining non-invasively the internal structure of manufactured parts, objects, and materials. NDE application areas include medicine, industrial manufacturing, military, homeland security, and airport luggage screening. X-ray measurement systems are most widely used because of their ability to image through a wide range of material densities (from human tissue in medical applications to the dense materials of weapon components). Traditional x-ray systems involve a single source and detector system that rotate and/or translate about the object under evaluation. At each angular location, the source projects x-rays through the object. The rays undergo attenuation proportional to the density of the object's constitutive material. The detector records a measure of the attenuation. Mathematical algorithms are used to invert the forward attenuated ray projection process to form images of the object. This is known as computed tomography (CT). In recent years, the single-source x-ray NDE systems have been generalized to arrays of x-ray sources. Array sources permit multiple views of the object with fewer rotations and translations of the source/detector system. The spatially diverse nature of x-ray array sources has the potential of reducing data collection time, reducing imaging artifacts, and increasing the resolution of the resultant images. Most of the existing CT algorithms were not derived from array source models with a spatially diverse set of viewing perspectives. Single-source x-ray CT data collection, processing, and imaging methods and algorithms are not applicable when the source location is expanded from one dimension (a rotating and/or translating point source) to two (a rotating and/or translating array). They must be reformulated. The goal of this project is to determine the applicability of x-ray array sources to problems of interest to LLNL and its customers. It is believed array

  15. X-ray sources in globular clusters of other galaxies

    CERN Document Server

    Lewin, W H G; Lewin, Walter H.G.; Verbunt, Frank

    2005-01-01

    A large number of X-ray sources in globular clusters of galaxies other than the Milky Way has been found with Chandra. We discuss three issues relating to these sources. The X-ray luminosity function (XLF) of the sources in globular clusters of M31 is marginally compatible with the XLF of globular clusters of the Milky Way. The individual XLFs of a dozen elliptical galaxies, after correction for incompleteness, are compatible with one another and show no break; however, the XLF found by adding the individual XLFs of elliptical galaxies has a break at L_x about 5x10(38) ergs/s. For the moment there is no evidence for a difference between the XLFs of sources inside and outside globular clusters of elliptical galaxies. It is not (yet?) possible to decide which fraction of low-mass X-ray binaries in elliptical galaxies outside globular clusters have formed inside globular clusters.

  16. Compact X-ray Source using a High Repetition Rate Laser and Copper Linac

    CERN Document Server

    Graves, W S; Brown, P; Carbajo, S; Dolgashev, V; Hong, K -H; Ihloff, E; Khaykovich, B; Lin, H; Murari, K; Nanni, E A; Resta, G; Tantawi, S; Zapata, L E; Kärtner, F X; Moncton, D E

    2014-01-01

    A design for a compact x-ray light source (CXLS) with flux and brilliance orders of magnitude beyond existing laboratory scale sources is presented. The source is based on inverse Compton scattering of a high brightness electron bunch on a picosecond laser pulse. The accelerator is a novel high-efficiency standing-wave linac and RF photoinjector powered by a single ultrastable RF transmitter at x-band RF frequency. The high efficiency permits operation at repetition rates up to 1 kHz, which is further boosted to 100 kHz by operating with trains of 100 bunches of 100 pC charge, each separated by 5 ns. The 100 kHz repetition rate is orders of magnitude beyond existing high brightness copper linacs. The entire accelerator is approximately 1 meter long and produces hard x-rays tunable over a wide range of photon energies. The colliding laser is a Yb:YAG solid-state amplifier producing 1030 nm, 100 mJ pulses at the same 1 kHz repetition rate as the accelerator. The laser pulse is frequency-doubled and stored for m...

  17. Development of a flat-panel X-ray source

    Science.gov (United States)

    Grant, Edwin Joseph

    A novel flat-panel transmission type X-ray source was developed for both medical and industrial use. Depending on the geometry of the given situation, the flat-panel X-ray source could be used in tomography, radiography or tomosynthesis. Furthermore, the unit could be used as a portable X-ray scanner or an integral part of an existing detection system. The design incorporates a field emission cathode made of ultra-nanocrystalline diamonds (UNCD) doped with nitrogen. These field emitters show good electron output at low power and can be deposited over large areas as is the case with carbon nanotube "forest" (CNT) cathodes. This work presents the first generation of the UNCD based FEA prototype which was manufactured at the Center of Nanoscale Material, within Argonne National Laboratory, with standard microfabrication techniques. The prototype is a 3 x 3 pixel field emission array (FEA), with a pixel size of 225 mum by 225 mum and a pitch of 500 mum. The fabricated cathode was developed using a microfabrication process which allows for individual electrically addressable UNCD gated arrays on-chip which demonstrated monolithic integration of the electron extraction grid. The transmission target consists of tungsten for X-ray generation, which is sputtered directly upon a thin aluminum sheet as an X-ray filter. A low voltage power supply allows for electron extraction between the cathode and the grid; while a high voltage power supply accelerates the electrons towards the anode. A low energy X-ray high purity germanium detector (HPGe) is mounted outside of the vacuum chamber for X-ray detection and measurement.

  18. Stellar X-ray Sources in the Rosette Nebula

    Institute of Scientific and Technical Information of China (English)

    W. P. Chen; P. S. Chiang; J. Z. Li

    2004-01-01

    We present optical photometric and spectroscopic studies of ROSAT X-ray stellar sources in the Rosette Nebula star-forming region. The brightest Xray sources are either massive stars or active T Tauri stars associated with the open cluster NGC 2244, or are foreground stars. Some of the spectra of the young stars newly identified in the region are presented.

  19. A JEM-X catalog of X-ray sources

    DEFF Research Database (Denmark)

    Westergaard, Niels Jørgen Stenfeldt; Chenevez, Jerome; Lund, Niels;

    2007-01-01

    The JEM-X catalog of X-ray sources presented here is based on detections in individual science windows with a sensitivity limit of about 10 mCrab (5-15 keV). It contains 127 sources and only those that can be identified from the existing reference catalog. The input data are taken from the, up...

  20. X-ray Counterparts of Infrared Faint Radio Sources

    Science.gov (United States)

    Schartel, Norbert

    2011-10-01

    Infrared Faint Radio Sources (IFRS) are radio sources with extremely faint or even absent infrared emission in deep Spitzer Surveys. Models of their spectral energy distributions, the ratios of radio to infrared flux densities and their steep radio spectra strongly suggest that IFRS are AGN at high redshifts (2IFRS, but if confirmed, the increased AGN numbers at these redshifts will account for the unresolved part of the X-ray background. The identification of X-ray counterparts of IFRS is considered to be the smoking gun for this hypothesis. We propose to observe 8 IFRS using 30ks pointed observations. X-ray detections of IFRS with different ratios of radio-to-infrared fluxes, will constrain the class-specific SED.

  1. Movable anode x-ray source with enhanced anode cooling

    Science.gov (United States)

    Bird, C.R.; Rockett, P.D.

    1987-08-04

    An x-ray source is disclosed having a cathode and a disc-shaped anode with a peripheral surface at constant radius from the anode axis opposed to the cathode. The anode has stub axle sections rotatably carried in heat conducting bearing plates which are mounted by thermoelectric coolers to bellows which normally bias the bearing plates to a retracted position spaced from opposing anode side faces. The bellows cooperate with the x-ray source mounting structure for forming closed passages for heat transport fluid. Flow of such fluid under pressure expands the bellows and brings the bearing plates into heat conducting contact with the anode side faces. A worm gear is mounted on a shaft and engages serrations in the anode periphery for rotating the anode when flow of coolant is terminated between x-ray emission events. 5 figs.

  2. Understanding X-ray reflection emissivity profiles in AGN: Locating the X-ray source

    CERN Document Server

    Wilkins, D R

    2012-01-01

    The illumination pattern (or emissivity profile) of the accretion disc due to the reflection of X-rays in AGN can be understood in terms of relativistic effects on the rays propagating from a source in a corona surrounding the central black hole, both on their trajectories and on the accretion disc itself. Theoretical emissivity profiles due to isotropic point sources as well as simple extended geometries are computed in general relativistic ray tracing simulations performed on graphics processing units (GPUs). Such simulations assuming only general relativity naturally explain the accretion disc emissivity profiles determined from relativistically broadened emission lines which fall off steeply (with power law indices of between 6 and 8) over the inner regions of the disc, then flattening off to almost a constant before tending to a constant power law of index 3 over the outer disc. Simulations for a variety of source locations, extents and geometries show how the emissivity profiles depend on these properti...

  3. A review of laser and synchrotron based X-ray sources

    Energy Technology Data Exchange (ETDEWEB)

    Smith, R. [Paris-Sud Univ., Orsay (France). LSAI; Key, M.H. [Paris-Sud Univ., Orsay (France). LSAI; Lawrence Livermore National Lab., CA (United States)

    2001-07-01

    The rapid development of laser technology and related progress in research using lasers is shifting the boundaries where laser based sources are preferred over other light sources particularly in the XUV and X-ray spectral region. Laser based sources have exceptional capability for short pulse and high brightness and with improvements in high repetition rate pulsed operation, such sources are also becoming more interesting for their average power capability. This study presents an evaluation of the current capabilities and near term future potential of laser based light sources and summarises, for the purpose of comparison, the characteristics and near term prospects of sources based on synchrotron radiation and free electron lasers. Relative comparisons are given within charts of peak brightness. (orig.)

  4. A multipurpose tunable source of monochromatic X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Chesta, M.A.; Plivelic, T.S.; Mainardi, R.T. E-mail: mainardi@mail.famaf.unc.edu.ar

    2002-02-01

    The emission of characteristic X-rays from any chemical element induced by beta particles of high energy (10{sup 5}-10{sup 6} eV) is much higher than photon excitation, with the possible exception of selective excitation. This work describes the properties of a variable energy X-ray generator that uses {sup 90}Sr as a source of beta particles and a multitarget array in a transparent source geometry. This compact device provides, through suitable selection of the target material, over 30 monoenergetic lines spread uniformly in the energy range of between 6 and 100 keV. The X-ray photon flux thus generated has an intensity of between 10{sup 2}-10{sup 3} s{sup -1} sr{sup -1} per MBq of the beta source activity. With this single beta source, the X-ray yield is higher as compared with generators using {sup 241}Am or other X- or gamma-ray sources with the same activity, and the line's intensity changes by less than a factor of three over the whole energy range.

  5. X-RAY SOURCES IN THE DWARF SPHEROIDAL GALAXY DRACO

    Energy Technology Data Exchange (ETDEWEB)

    Sonbas, E. [University of Adiyaman, Department of Physics, 02040 Adiyaman (Turkey); Rangelov, B.; Kargaltsev, O.; Dhuga, K. S.; Hare, J.; Volkov, I., E-mail: edasonbas@yahoo.com [Department of Physics, The George Washington University, Washington, DC 20052 (United States)

    2016-04-10

    We present the spectral analysis of an 87 ks XMM-Newton observation of Draco, a nearby dwarf spheroidal galaxy. Of the approximately 35 robust X-ray source detections, we focus our attention on the brightest of these sources, for which we report X-ray and multiwavelength parameters. While most of the sources exhibit properties consistent with active galactic nuclei, few of them possess the characteristics of low-mass X-ray binaries (LMXBs) and cataclysmic variable (CVs). Our analysis places constraints on the population of X-ray sources with L{sub X} > 3 × 10{sup 33} erg s{sup −1} in Draco, suggesting that there are no actively accreting black hole and neutron star binaries. However, we find four sources that could be quiescent state LMXBs/CVs associated with Draco. We also place constraints on the central black hole luminosity and on a dark matter decay signal around 3.5 keV.

  6. Characterization of X-Ray Diffraction System with a Microfocus X-Ray Source and a Polycapillary Optic

    Science.gov (United States)

    Gubarev, Mikhail; Marshall, Joy K.; Ciszak, Ewa; Ponomarev, Igor

    2000-01-01

    We present here an optimized microfocus x-ray source and polycapillary optic system designed for diffraction of small protein crystals. The x-ray beam is formed by a 5.5mm focal length capillary collimator coupled with a 40 micron x-ray source operating at 46Watts. Measurements of the x-ray flux, the divergence and the spectral characteristics of the beam are presented, This optimized system provides a seven fold greater flux than our recently reported configuration [M. Gubarev, et al., J. of Applied Crystallography (2000) 33, in press]. We now make a comparison with a 5kWatts rotating anode generator (Rigaku) coupled with confocal multilayer focusing mirrors (Osmic, CMF12- 38Cu6). The microfocus x-ray source and polycapillary collimator system delivers 60% of the x-ray flux from the rotating anode system. Additional ways to improve our microfocus x-ray system, and thus increase the x-ray flux will be discussed.

  7. Flares in the X-ray source EXO 2030 + 375

    Science.gov (United States)

    Apparao, Krishna M. V.

    1991-01-01

    Six X-ray flares were observed in the source EXO 2030 + 375 with an average time interval of about 4 hr between the flares. It is shown here that the flares can be due to Rayleigh-Taylor instabilities near the magnetospheric boundary of the neutron star when it reaches the equilibrium period.

  8. Stellar X-ray sources in the Chandra COSMOS survey

    CERN Document Server

    Wright, Nicholas J; Civano, Francesca

    2010-01-01

    We present an analysis of the X-ray properties of a sample of solar- and late-type field stars identified in the Chandra Cosmic Evolution Survey (COSMOS), a deep (160ks) and wide (0.9 deg2) extragalactic survey. The sample of 60 sources was identified using both morphological and photometric star/galaxy separation methods. We determine X-ray count rates, extract spectra and light curves and perform spectral fits to determine fluxes and plasma temperatures. Complementary optical and near-IR photometry is also presented and combined with spectroscopy for 48 of the sources to determine spectral types and distances for the sample. We find distances ranging from 30pc to ~12kpc, including a number of the most distant and highly active stellar X-ray sources ever detected. This stellar sample extends the known coverage of the L_X-distance plane to greater distances and higher luminosities, but we do not detect as many intrinsically faint X-ray sources compared to previous surveys. Overall the sample is typically more...

  9. Compact X-ray Light Source Workshop Report

    Energy Technology Data Exchange (ETDEWEB)

    Thevuthasan, Suntharampillai; Evans, James E.; Terminello, Louis J.; Koppenaal, David W.; Manke, Kristin L.; Plata, Charity

    2012-12-01

    This report, produced jointly by EMSL and FCSD, is the result of a workshop held in September 2011 that examined the utility of a compact x-ray light source (CXLS) in addressing many scientific challenges critical to advancing energy science and technology.

  10. High brightness single photon sources based on photonic wires

    DEFF Research Database (Denmark)

    Claudon, J.; Bleuse, J.; Bazin, M.

    2009-01-01

    We present a novel single-photon-source based on the emission of a semiconductor quantum dot embedded in a single-mode photonic wire. This geometry ensures a very large coupling (> 95%) of the spontaneous emission to the guided mode. Numerical simulations show that a photon collection efficiency...

  11. Chandra ACIS Survey of X-ray Point Sources in Nearby Galaxies. II. X-ray Luminosity Functions and Ultraluminous X-ray Sources

    CERN Document Server

    Wang, Song; Liu, Jifeng; Bregman, Joel N

    2016-01-01

    Based on the recently completed {\\it Chandra}/ACIS survey of X-ray point sources in nearby galaxies, we study the X-ray luminosity functions (XLFs) for X-ray point sources in different types of galaxies and the statistical properties of ultraluminous X-ray sources (ULXs). Uniform procedures are developed to compute the detection threshold, to estimate the foreground/background contamination, and to calculate the XLFs for individual galaxies and groups of galaxies, resulting in an XLF library for 343 galaxies of different types. With the large number of surveyed galaxies, we have studied the XLFs and ULX properties across different host galaxy types, and confirm with good statistics that the XLF slope flattens from lenticular ($\\alpha\\sim1.50\\pm0.07$) to elliptical ($\\sim1.21\\pm0.02$), to spirals ($\\sim0.80\\pm0.02$), to peculiars ($\\sim0.55\\pm0.30$), and to irregulars ($\\sim0.26\\pm0.10$). The XLF break dividing the neutron star and black hole binaries is also confirmed, albeit at quite different break luminosi...

  12. Ultrafast outflows in ultraluminous X-ray sources

    CERN Document Server

    Pinto, Ciro; Middleton, Matthew; Walton, Dom

    2016-01-01

    Ultraluminous X-ray sources (ULXs) are bright extragalactic sources with X-ray luminosities above 10^39 erg/s powered by accretion onto compact objects. According to the first studies performed with XMM-Newton ULXs seemed to be excellent candidates to host intermediate-mass black holes (10^2-4 solar masses). However, in the last years the interpretation of super-Eddington accretion onto stellar-mass black holes or neutron stars for most ULXs has gained a strong consensus. One critical missing piece to confirm the super-Eddington scenario was the direct detection of the massive, radiatively-driven winds expected as atomic emission/absorption lines in ULX spectra. The first evidence for winds was found as residuals in the soft X-ray spectra of ULXs. Most recently we have been able to resolve these residuals into rest-frame emission and blueshifted (~0.2c) absorption lines arising from highly ionized gas in the deep high-resolution XMM-Newton spectra of two ultraluminous X-ray sources. The compact object is ther...

  13. 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).

  14. Automatic classification of time-variable X-ray sources

    Energy Technology Data Exchange (ETDEWEB)

    Lo, Kitty K.; Farrell, Sean; Murphy, Tara; Gaensler, B. M. [Sydney Institute for Astronomy, School of Physics, The University of Sydney, Sydney, NSW 2006 (Australia)

    2014-05-01

    To maximize the discovery potential of future synoptic surveys, especially in the field of transient science, it will be necessary to use automatic classification to identify some of the astronomical sources. The data mining technique of supervised classification is suitable for this problem. Here, we present a supervised learning method to automatically classify variable X-ray sources in the Second XMM-Newton Serendipitous Source Catalog (2XMMi-DR2). Random Forest is our classifier of choice since it is one of the most accurate learning algorithms available. Our training set consists of 873 variable sources and their features are derived from time series, spectra, and other multi-wavelength contextual information. The 10 fold cross validation accuracy of the training data is ∼97% on a 7 class data set. We applied the trained classification model to 411 unknown variable 2XMM sources to produce a probabilistically classified catalog. Using the classification margin and the Random Forest derived outlier measure, we identified 12 anomalous sources, of which 2XMM J180658.7–500250 appears to be the most unusual source in the sample. Its X-ray spectra is suggestive of a ultraluminous X-ray source but its variability makes it highly unusual. Machine-learned classification and anomaly detection will facilitate scientific discoveries in the era of all-sky surveys.

  15. AGN content of X-ray, IR and radio sources

    Science.gov (United States)

    Mickaelian, A. M.; Paronyan, G. M.; Abrahamyan, H. V.; Gyulzadyan, M. V.; Mikayelyan, G. A.

    2016-09-01

    We have carried out a number of surveys and identification works related to X-ray, IR and radio sources and searched for extragalactic ones. Among them, most interesting are Active Galactic Nuclei (AGN) and Starburst (SB) Galaxies. Some 4500 AGN have been revealed from ROSAT BSC and FSC sources, and many more are hidden ones; those showing evidence of activity but with no emission lines in optical wavelengths. We estimated AGN content of X-ray sources as 52.9%. IR sources contain thousands of SBs, and most important are those having signs of interaction and/or merging. We have carried out optical identifications of IRAS point sources, and 1278 IR galaxies have been revealed, including LIRGs and ULIRGs. We have also combined IRAS PSC and FSC catalogs and compiled its extragalactic sample, which allowed to estimate AGN content among IR sources as 23.7%. Extragalactic radio sources contain bright galaxies, AGN and SBs. We have studied the border between AGN and normal galaxies by radio/optical flux ratios to establish which objects may be attributed to AGN based on radio properties. Interestingly, absolute majority of objects associated with both X-ray and radio sources are AGN.

  16. High power bremsstrahlung X-ray source for radiation processing

    Science.gov (United States)

    Yotsumoto, K.; Sunaga, H.; Tanaka, S.; Kanazawa, T.; Agematsu, T.; Tanaka, R.; Yoshida, K.; Taniguchi, S.; Sakamoto, I.; Tamura, N.

    The high power X-ray irradiation facility designed for the sterilization of medical appliances is described. The X-ray source consists of the 5 MeV, 300 kW Cockcroft Walton type of electron accelerator and the water cooled tantalum target. Conditions necessary for designing the X-ray target are conversion efficiency from electron beam to X-ray, thermal conductivity, readiness for machining and cost of the material. The conversion efficiency was determined through the Monte Carlo type calculation and obtained as 10.8 % for 3.667 g/cm 2 thickness (1 csda range) of tantalum target. In order to obtain the data on the source design, experiments have been carried out at the JAERI TAKASAKI 2 MeV, 60 kW Cockcroft-Walton type of electron accelerator equipped with a tantalum target. The size of package and the speed of conveyor was determined through the calculation of the absorbed dose distribution in the irradiated medium and the utilization efficiency.

  17. Near-Infrared Spectroscopy of Faint Discrete X-ray Point Sources Constituting the Galactic Ridge X-ray Emission

    CERN Document Server

    Morihana, Kumiko; Dubath, Pierre; Yoshida, Tessei; Suzuki, Kensuke; Ebisawa, Ken

    2016-01-01

    The Galactic Ridge X-ray Emission (GRXE) is apparently extended X-ray emission along the Galactic Plane. The X-ray spectrum is characterized by hard continuum with a strong Fe K emission feature in the 6-7 keV band. A substantial fraction (~80%) of the GRXE in the Fe band was resolved into point sources by deep Chandra imaging observations, thus GRXE is mostly composed of dim Galactic X-ray point sources at least in this energy band. To investigate the populations of these dim X-ray point sources, we carried out Near-Infrared (NIR) follow-up spectroscopic observations in two deep Chandra fields located in the Galactic plane at (l,b)=(0.1{\\arcdeg}, -1.4{\\arcdeg}) and (28.5{\\arcdeg}, 0.0{\\arcdeg}) using NTT/SofI and Subaru/MOIRCS. We obtained well-exposed NIR spectra from 65 objects and found that there are three main classes of Galactic sources based on the X-ray color and NIR spectral features: those having (A) hard X-ray spectra and NIR emission features such as HI(Br{\\gamma}), HeI, and HeII (2 objects), (B)...

  18. NuSTAR Hard X-ray Survey of the Galactic Center Region II: X-ray Point Sources

    CERN Document Server

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

    2016-01-01

    We present the first survey results of hard X-ray point sources in the Galactic Center (GC) region by NuSTAR. We have discovered 70 hard (3-79 keV) X-ray point sources in a 0.6 deg^2 region around Sgr A* with a total exposure of 1.7 Ms, and 7 sources in the Sgr B2 field with 300 ks. We identify clear Chandra counterparts for 58 NuSTAR sources and assign candidate counterparts for the remaining 19. The NuSTAR survey reaches X-ray luminosities of ~4 x and ~8 x 10^32 erg s^-1 at the GC (8 kpc) in the 3-10 and 10-40 keV bands, respectively. The source list includes three persistent luminous X-ray binaries and the likely run-away pulsar called the Cannonball. New source-detection significance maps reveal a cluster of hard (>10 keV) X-ray sources near the Sgr A diffuse complex with no clear soft X-ray counterparts. The severe extinction observed in the Chandra spectra indicates that all the NuSTAR sources are in the central bulge or are of extragalactic origin. Spectral analysis of relatively bright NuSTAR sources ...

  19. Distributed source x-ray tube technology for tomosynthesis imaging

    Science.gov (United States)

    Sprenger, F.; Calderon-Colon, X.; Cheng, Y.; Englestad, K.; Lu, J.; Maltz, J.; Paidi, A.; Qian, X.; Spronk, D.; Sultana, S.; Yang, G.; Zhou, O.

    2010-04-01

    Tomosynthesis imaging requires projection images from different viewing angles. Conventional systems use a moving xray source to acquire the individual projections. Using a stationary distributed x-ray source with a number of sources that equals the number of required projections, this can be achieved without any mechanical motion. Advantages are a potentially faster image acquisition speed, higher spatial and temporal resolution and simple system design. We present distributed x-ray sources based on carbon nanotube (CNT) field emission cathodes. The field emission cathodes deliver the electrons required for x-ray production. CNT emitters feature a stable emission at high current density, a cold emission, excellent temporal control of the emitted electrons and good configurability. We discuss the use of stationary sources for two applications: (i) a linear tube for stationary digital breast tomosynthesis (sDBT), and (ii) a square tube for on-board tomosynthesis image-guided radiation therapy (IGRT). Results from high energy distributed sources up to 160kVp are also presented.

  20. ISO investigates the nature of extremely-red hard X-ray sources responsible for the X-ray background

    CERN Document Server

    Franceschini, A; Césarsky, C J; Elbaz, D; Flores, H; Granato, G L; Franceschini, Alberto; Fadda, Dario; Cesarsky, Catherine; Elbaz, David; Flores, Hector; Granato, Gian Luigi

    2001-01-01

    We analyse very deep X-ray and mid-IR surveys in common areas of the Lockman Hole and the HDF North to study the sources of the X-ray background (XRB) and to test the standard obscured accretion paradigm. We detect with ISO a rich population of X-ray luminous sources with red optical colours, including a fraction identified with Extremely Red Objects (R-K > 5) and galaxies with SEDs typical of normal massive ellipticals or spirals at z ~ 1. The high 0.5-10 keV X-ray luminosities of these objects (1E43-1E45 erg/s) indicate that the ultimate energy source is gravitational accretion, while the X-ray to IR flux ratios and the X-ray spectral hardness show evidence of photoelectric absorption at low X-ray energies. An important hint on the physics comes from the mid-IR data at 6.7 and 15 um, well reproduced by model spectra of completely obscured quasars under standard assumptions and l.o.s. optical depths tau ~ 30-40. Other predictions of the standard XRB picture, like the distributions of intrinsic bolometric lum...

  1. Measuring x-ray spectra of flash radiographic sources

    Science.gov (United States)

    Gehring, Amanda E.; Espy, Michelle A.; Haines, Todd J.; Mendez, Jacob; Moir, David C.; Sedillo, Robert; Shurter, Roger P.; Volegov, Petr; Webb, Timothy J.

    2015-08-01

    A Compton spectrometer has been re-commissioned for measurements of flash radiographic sources. The determination of the energy spectrum of these sources is difficult due to the high count rates and short nature of the pulses (~50 ns). The spectrometer is a 300 kg neodymium-iron magnet which measures spectra in the <1 MeV to 20 MeV energy range. Incoming x-rays are collimated into a narrow beam incident on a converter foil. The ejected Compton electrons are collimated so that the forward-directed electrons enter the magnetic field region of the spectrometer. The position of the electrons at the magnet's focal plane is a function of their momentum, allowing the x-ray spectrum to be reconstructed. Recent measurements of flash sources are presented.

  2. Gravitational waves from remnants of ultraluminous X-ray sources

    CERN Document Server

    Hopman, C; Hopman, Clovis; Zwart, Simon Portegies

    2005-01-01

    Ultraluminous X-ray sources (ULXs) with X-ray luminosities larger than the Eddington luminosity of stellar mass objects may be powered by intermediate mass black holes (IBHs) of masses Mbh~10^3Msun. If IBHs form in young dense stellar clusters, they can be fed by Roche lobe overflow from a tidally captured massive (Ms>10Msun) stellar companion. After the donor leaves the main sequence it forms a compact remnant, which spirals in due to gravitational wave (GW) emission. We show that space based detectors such as the Light Interferometer Space Antenna are likely to detect several of these sources. GW sources stemming from this scenario have small eccentricities which give distinct GW signals. Detection of such a GW signal will unambiguously prove the existence of IBHs, and support the hypothesis that some ULXs are powered by IBHs with captured companions.

  3. High duty cycle inverse Compton scattering X-ray source

    Science.gov (United States)

    Ovodenko, A.; Agustsson, R.; Babzien, M.; Campese, T.; Fedurin, M.; Murokh, A.; Pogorelsky, I.; Polyanskiy, M.; Rosenzweig, J.; Sakai, Y.; Shaftan, T.; Swinson, C.

    2016-12-01

    Inverse Compton Scattering (ICS) is an emerging compact X-ray source technology, where the small source size and high spectral brightness are of interest for multitude of applications. However, to satisfy the practical flux requirements, a high-repetition-rate ICS system needs to be developed. To this end, this paper reports the experimental demonstration of a high peak brightness ICS source operating in a burst mode at 40 MHz. A pulse train interaction has been achieved by recirculating a picosecond CO2 laser pulse inside an active optical cavity synchronized to the electron beam. The pulse train ICS performance has been characterized at 5- and 15- pulses per train and compared to a single pulse operation under the same operating conditions. With the observed near-linear X-ray photon yield gain due to recirculation, as well as noticeably higher operational reliability, the burst-mode ICS offers a great potential for practical scalability towards high duty cycles.

  4. Laser-driven soft-X-ray undulator source

    Energy Technology Data Exchange (ETDEWEB)

    Fuchs, Matthias

    2010-08-04

    The experimental results described in this thesis demonstrate the successful synergy between the research fields described above: the development of an undulator source driven by laser-plasma accelerated electron beams. First efforts in this new field have led to the production of radiation in the visible to infrared part of the electromagnetic spectrum [Schlenvoigt et al., 2008]. In contrast to these early achievements, the experiment described here shows the successful production of laser-driven undulator radiation in the soft-X-ray range with a remarkable reproducibility. The source produced tunable, collimated beams with a wavelength of {proportional_to}17 nm from a compact setup. Undulator spectra were detected in {proportional_to}70% of consecutive driver-laser shots, which is a remarkable reproducibility for a first proof-of-concept demonstration using ultra-high intensity laser systems. This can be attributed to a stable electron acceleration scheme as well as to the first application of miniature magnetic quadrupole lenses with laseraccelerated beams. The lenses significantly reduce the electron beam divergence and its angular shot-to-shot fluctuations The setup of this experiment is the foundation of potential university-laboratory-sized, highly-brilliant hard X-ray sources. By increasing the electron energy to about 1 GeV, X-ray pulses with an expected duration of {proportional_to}10 fs and a photon energy of 1 keV could be produced in an almost identical arrangement. It can also be used as a testbed for the development of a free-electron laser of significantly smaller dimension than facilities based on conventional accelerators [Gruener et al., 2007]. Such compact sources have the potential for application in many fields of science. In addition, these developments could lead to ideal sources for ultrafast pump-probe experiments due to the perfect synchronization of the X-ray beam to the driver laser. (orig.)

  5. The Polarimeter for Relativistic Astrophysical X-ray Sources

    Science.gov (United States)

    Jahoda, Keith; Kallman, Timothy R.; Kouveliotou, Chryssa; Angelini, Lorella; Black, J. Kevin; Hill, Joanne E.; Jaeger, Theodore; Kaaret, Philip E.; Markwardt, Craig B.; Okajima, Takashi; Petre, Robert; Schnittman, Jeremy; Soong, Yang; Strohmayer, Tod E.; Tamagawa, Toru; Tawara, Yuzuru

    2016-07-01

    The Polarimeter for Relativistic Astrophysical X-ray Sources (PRAXyS) is one of three Small Explorer (SMEX) missions selected by NASA for Phase A study, with a launch date in 2020. The PRAXyS Observatory exploits grazing incidence X-ray mirrors and Time Projection Chamber Polarimeters capable of measuring the linear polarization of cosmic X-ray sources in the 2-10 keV band. PRAXyS combines well-characterized instruments with spacecraft rotation to ensure low systematic errors. The PRAXyS payload is developed at the Goddard Space Flight Center with the Johns Hopkins University Applied Physics Laboratory, University of Iowa, and RIKEN (JAXA) collaborating on the Polarimeter Assembly. The LEOStar-2 spacecraft bus is developed by Orbital ATK, which also supplies the extendable optical bench that enables the Observatory to be compatible with a Pegasus class launch vehicle. A nine month primary mission will provide sensitive observations of multiple black hole and neutron star sources, where theory predicts polarization is a strong diagnostic, as well as exploratory observations of other high energy sources. The primary mission data will be released to the community rapidly and a Guest Observer extended mission will be vigorously proposed.

  6. Kinematics of Compton backscattering x-ray source for angiography

    Energy Technology Data Exchange (ETDEWEB)

    Blumberg, L.N.

    1992-05-01

    Calculations of X-Ray production rates, energy spread, and spectrum of Compton-backscattered photons from a Free Electron Laser on an electron beam in a low energy (136-MeV) compact (8.5-m circumference) storage ring indicate that an X-Ray intensity of 34.6 10{sup 7} X-Ray photons per 0.5-mm {times} 0.5-mm pixel for Coronary Angiography near the 33.169-keV iodine K-absorption edge can be achieved in a 4-msec pulse within a scattering cone of 1-mrad half angle. This intensity, at 10-m from the photon-electron interaction point to the patient is about a factor of 10 larger than presently achieved from a 4.5-T superconducting wiggler source in the NSLS 2.5-GeV storage ring and over an area about 5 times larger. The 2.2-keV energy spread of the Compton-backscattered beam is, however, much larger than the 70-eV spread presently attained form the wiggler source and use of a monochromator. The beam spot at the 10-m interaction point-to-patient distance is 20-mm diameter; larger spots are attainable at larger distances but with a corresponding reduction in X-Ray flux. Such a facility could be an inexpensive clinical alternative to present methods of non-invasive Digital Subtraction Angiography (DSA), small enough to be deployed in an urban medical center, and could have other medical, industrial and aerospace applications. Problems with the Compton backscattering source include laser beam heating of the mirror in the FEL oscillator optical cavity, achieving a large enough X-Ray beam spot at the patient, and obtaining radiation damping of the transverse oscillations and longitudinal emittance dilution of the storage ring electron beam resulting from photon-electron collisions without going to higher electron energy where the X-Ray energy spread becomes excessive for DSA. 38 refs.

  7. First Search for an X-ray -- Optical Reverberation Signal in an Ultraluminous X-ray Source

    CERN Document Server

    Pasham, Dheeraj R; Cenko, S Bradley; Trippe, Margaret L; Mushotzky, Richard F; Gandhi, Poshak

    2016-01-01

    Using simultaneous optical (VLT/FORS2) and X-ray (XMM-Newton) data of NGC 5408, we present the first ever attempt to search for a reverberation signal in an ultraluminous X-ray source (NGC 5408 X-1). The idea is similar to AGN broad line reverberation mapping where a lag measurement between the X-ray and the optical flux combined with a Keplerian velocity estimate should enable us to weigh the central compact object. We find that although NGC 5408 X-1's X-rays are variable on a timescale of a few hundred seconds (RMS of 9.0$\\pm$0.5%), the optical emission does not show any statistically significant variations. We set a 3$\\sigma$ upper limit on the RMS optical variability of 3.3%. The ratio of the X-ray to the optical variability is an indicator of X-ray reprocessing efficiency. In X-ray binaries, this ratio is roughly 5. Assuming a similar ratio for NGC 5408 X-1, the expected RMS optical variability is $\\approx$2% which is still a factor of roughly two lower than what was possible with the VLT observations in...

  8. Geometry calibration between X-ray source and detector for tomosynthesis with a portable X-ray system.

    Science.gov (United States)

    Sato, Kohei; Ohnishi, Takashi; Sekine, Masashi; Haneishi, Hideaki

    2017-05-01

    Tomosynthesis is attracting attention as a low-dose tomography technology compared with X-ray CT. However, conventional tomosynthesis imaging devices are large and stationary. Furthermore, there is a limitation in the working range of the X-ray source during image acquisition. We have previously proposed the use of a portable X-ray device for tomosynthesis that can be used for ward rounds and emergency medicine. The weight of this device can be reduced by using a flat panel detector (FPD), and flexibility is realized by the free placement of the X-ray source and FPD. Tomosynthesis using a portable X-ray device requires calibration of the geometry between the X-ray source and detector at each image acquisition. We propose a method for geometry calibration and demonstrate tomosynthesis image reconstruction by this method. An image processing-based calibration method using an asymmetric and multilayered calibration object (AMCO) is presented. Since the AMCO is always attached to the X-ray source housing for geometry calibration, the additional setting of a calibration object or marker around or on the patients is not required. The AMCO's multilayer structure improves the calibration accuracy, especially in the out-of-plane direction. Two experiments were conducted. The first was performed to evaluate the calibration accuracy using an XY positioning stage and a gonio stage. As a result, an accuracy of approximately 1 mm was achieved both in the in-plane and out-of-plane directions. An angular accuracy of approximately [Formula: see text] was confirmed. The second experiment was conducted to evaluate the reconstructed image using a foot model phantom. Only the sagittal plane could be clearly observed with the proposed method. We proposed a tomosynthesis imaging system using a portable X-ray device. From the experimental results, the proposed method could provide sufficient calibration accuracy and a clear sagittal plane of the reconstructed tomosynthesis image.

  9. Towards brilliant, compact x-ray sources: a new x-ray photonic device

    Science.gov (United States)

    Scherer, Brian; Mandal, Sudeep; Salisbury, Joshua; Edic, Peter; Hopkins, Forrest; Lee, Susanne M.

    2017-05-01

    General Electric has designed an innovative x-ray photonic device that concentrates a polychromatic beam of diverging x-rays into a less divergent, parallel, or focused x-ray beam. The device consists of multiple, thin film multilayer stacks. X-rays incident on a given multilayer stack propagate within a high refractive index transmission layer while undergoing multiple total internal reflections from a novel, engineered multilayer containing materials of lower refractive index. Development of this device could lead to order-of-magnitude flux density increases, over a large broadband energy range from below 20 keV to above 300 keV. In this paper, we give an overview of the device and present GE's progress towards fabricating prototype devices.

  10. Ultraluminous X-ray Sources in Interacting Galaxies

    CERN Document Server

    Swartz, Douglas A

    2009-01-01

    I give a brief review of how X-rays from nearby galaxies are used as direct tracers of recent star formation. This leads to the conclusion that it is the most luminous point-like sources that are associated with star formation and that the majority of these are high-mass X-ray binaries.I then discuss a recent study that shows that ULXs are preferentially found in regions as young as or younger than typical HII regions in their host galaxies. Finally, I describe a new study that attempts to determine the maximum luminosity of ULXs in the local universe by searching for them in interacting galaxies where the star formation rate is high.

  11. Reionization by UV or X-ray sources

    CERN Document Server

    Baek, S; Di Matteo, P; Revaz, Y; Combes, F

    2010-01-01

    We present simulations of the 21-cm signal during the Epoch of reionization. We focus on modeling properly the absorption regime in the presence of inhomogeneous Wouthuysen-Field effect and X-ray heating. We have run radiative transfer simulations for three bands in the source spectrum (Lyman, UV and X-ray) in order to fully account for these processes. We find that the brightness temperature fluctuation of the 21 cm signal has an amplitude larger than 100 mK during the early reionization, up to 10 times higher than the typical amplitude of a few 10 mK obtained during the later emission phase. More importantly, we find that even a rather high contribution from QSO-like sources only damps the absorption regime without erasing it. Heating the IGM with X-ray takes time. Our results show that observations of the early reionization will probably benefit from a higher signal-to-noise value than during later stages. Analyzing the statistical properties of the signal (power spectrum and PDF) we found three diagnostic...

  12. Two eclipsing ultraluminous X-ray sources in M 51

    CERN Document Server

    Urquhart, Ryan

    2016-01-01

    We present the discovery, from archival Chandra and XMM-Newton data, of X-ray eclipses in two ultraluminous X-ray sources (ULXs), located in the same region of the galaxy M 51: CXOM51 J132940.0$+$471237 (ULX-1, for simplicity) and CXOM51 J132939.5$+$471244 (ULX-2). Three eclipses were detected for ULX-1, two for ULX-2. The presence of eclipses puts strong constraints on the viewing angle, suggesting that both ULXs are seen almost edge-on and are certainly not beamed towards us. Despite the similar viewing angles and luminosities ($L_{\\rm X} \\approx 2 \\times 10^{39}$ erg s$^{-1}$ in the $0.3$-$8$ keV band for both sources), their X-ray properties are different. ULX-1 has a soft spectrum, well fitted by Comptonization emission from a medium with electron temperature $kT_e \\approx 1$ keV. ULX-2 is harder, well fitted by a slim disk with $kT_{\\rm in} \\approx 1.5$-$1.8$ keV and normalization consistent with a $\\sim 10 M_{\\odot}$ black hole. ULX-1 has a significant contribution from multi-temperature thermal plasma...

  13. Matching microlensing events with X-ray sources

    CERN Document Server

    Sartore, N

    2011-01-01

    The detection of old neutron stars and black holes in isolation is one of the cornerstones of compact object astrophysics. Microlensing surveys may help on this purpose since the lensing mechanism is independent of the emission properties of the lens. Indeed, several black hole candidates deriving through microlensing observations have been reported in the literature. The identification of counterparts, especially in the X-rays, would be a strong argument in favor of the compact nature of these lenses. We perform a cross-correlation between the catalogs of microlensing events by the OGLE, MACHO and MOA teams, and those of X-rays sources from XMM-Newton and Chandra satellites. Based on our previous work, we select only microlensing events longer than 100 days, which should contain a large fraction of lenses as compact objects. Our matching criterion takes into account the positional coincidence in the sky. We find a single match between a microlensing event OGLE 2004-BLG-81 and the X-ray source 2XMM J180540.5-...

  14. Deterministic Chaos in the X-ray Sources

    Science.gov (United States)

    Grzedzielski, M.; Sukova, P.; Janiuk, A.

    2015-12-01

    Hardly any of the observed black hole accretion disks in X-ray binaries and active galaxies shows constant flux. When the local stochastic variations of the disk occur at specific regions where a resonant behaviour takes place, there appear the quasi-periodic oscillations (QPOs). If the global structure of the flow and its non-linear hydrodynamics affects the fluctuations, the variability is chaotic in the sense of deterministic chaos. Our aim is to solve a problem of the stochastic versus deterministic nature of the black hole binary variabilities. We use both observational and analytic methods. We use the recurrence analysis and we study the occurence of long diagonal lines in the recurrence plot of observed data series and compare it to the surrogate series. We analyze here the data of two X-ray binaries - XTE J1550-564 and GX 339-4 observed by Rossi X-ray Timing Explorer. In these sources, the non-linear variability is expected because of the global conditions (such as the mean accretion rate) leading to the possible instability of an accretion disk. The thermal-viscous instability and fluctuations around the fixed-point solution occurs at high accretion rate, when the radiation pressure gives dominant contribution to the stress tensor.

  15. Deterministic chaos in the X-Ray sources

    CERN Document Server

    Grzedzielski, M; Janiuk, A

    2015-01-01

    Hardly any of the observed black hole accretion disks in X-Ray binaries and active galaxies shows constant flux. When the local stochastic variations of the disk occur at specific regions where a resonant behaviour takes place, there appear the Quasi-Periodic Oscillations (QPOs). If the global structure of the flow and its non-linear hydrodynamics affects the fluctuations, the variability is chaotic in the sense of deterministic chaos. Our aim is to solve a problem of the stochastic versus deterministic nature of the black hole binaries vari- ability. We use both observational and analytic methods. We use the recurrence analysis and we study the occurence of long diagonal lines in the recurrence plot of observed data series and compare it to the sur- rogate series. We analyze here the data of two X-Ray binaries - XTE J1550-564, and GX 339-4 observed by Rossi X-ray Timing Explorer. In these sources, the non-linear variability is expected because of the global conditions (such as the mean accretion rate) leadin...

  16. Deterministic Chaos in the X-ray Sources

    Indian Academy of Sciences (India)

    M. Grzedzielski; P. Sukova; A. Janiuk

    2015-12-01

    Hardly any of the observed black hole accretion disks in X-ray binaries and active galaxies shows constant flux. When the local stochastic variations of the disk occur at specific regions where a resonant behaviour takes place, there appear the quasi-periodic oscillations (QPOs). If the global structure of the flow and its non-linear hydrodynamics affects the fluctuations, the variability is chaotic in the sense of deterministic chaos. Our aim is to solve a problem of the stochastic versus deterministic nature of the black hole binary variabilities. We use both observational and analytic methods. We use the recurrence analysis and we study the occurence of long diagonal lines in the recurrence plot of observed data series and compare it to the surrogate series. We analyze here the data of two X-ray binaries – XTE J1550-564 and GX 339-4 observed by Rossi X-ray Timing Explorer. In these sources, the non-linear variability is expected because of the global conditions (such as the mean accretion rate) leading to the possible instability of an accretion disk. The thermal-viscous instability and fluctuations around the fixedpoint solution occurs at high accretion rate, when the radiation pressure gives dominant contribution to the stress tensor.

  17. An Observational Diagnostic for Ultraluminous X-Ray Sources

    CERN Document Server

    Kalogera, V; Ivanova, N; King, A R

    2004-01-01

    We consider observational tests for the nature of Ultraluminous X-ray sources (ULXs). These must distinguish between thermal-timescale mass transfer on to stellar-mass black holes leading to anisotropic X-ray emission, and accretion on to intermediate-mass black holes. We suggest that long-term transient behavior via the thermal-viscous disk instability could discriminate between these two possibilities for ULXs in regions of young stellar populations. Thermal-timescale mass transfer generally produces stable disks and persistent X-ray emission. In contrast, mass transfer from massive stars to black holes produces unstable disks and thus transient behavior, provided that the black hole mass exceeds some minimum value. This minimum mass depends primarily on the donor mass and evolutionary state. We show that it exceeds 50 solar masses for a large fraction (greater than 90%) of the mass-transfer lifetime for the most likely donors in young clusters. Thus if long-term monitoring reveals a large transient fractio...

  18. Compact X-ray source based on Compton backscattering

    CERN Document Server

    Bulyak, E V; Zelinsky, A; Karnaukhov, I; Kononenko, S; Lapshin, V G; Mytsykov, A; Telegin, Yu P; Khodyachikh, A; Shcherbakov, A; Molodkin, V; Nemoshkalenko, V; Shpak, A

    2002-01-01

    The feasibility study of an intense X-ray source based on the interaction between the electron beam in a compact storage ring and the laser pulse accumulated in an optical resonator is carried out. We propose to reconstruct the 160 MeV electron storage ring N-100, which was shutdown several years ago. A new magnetic lattice will provide a transverse of electron beam size of approx 35 mu m at the point of electron beam-laser beam interaction. The proposed facility is to generate X-ray beams of intensity approx 2.6x10 sup 1 sup 4 s sup - sup 1 and spectral brightness approx 10 sup 1 sup 2 phot/0.1%bw/s/mm sup 2 /mrad sup 2 in the energy range from 10 keV up to 0.5 MeV. These X-ray beam parameters meet the requirements for most of technological and scientific applications. Besides, we plan to use the new facility for studying the laser cooling effect.

  19. Compton Scattering and Its Applications: The PLEIADES Femtosecond X-ray Source at LLNL

    Energy Technology Data Exchange (ETDEWEB)

    Hartemann, F V; Brown, W J; Anderson, S G; Barty, C P J; Betts, S M; Booth, R; Crane, J K; Cross, R R; Fittinghoff, D N; Gibson, D J; Kuba, J; Rupp, B; Tremaine, A M; Springer, P T

    2003-05-01

    Remarkable developments in critical technologies including terawatt-class lasers using chirped-pulse amplification, high brightness photoinjectors, high-gradient accelerators, and superconducting linacs make it possible to design and operate compact, tunable, subpicosecond Compton scattering x-ray sources with a wide variety of applications. In such novel radiation sources, the collision between a femtosecond laser pulse and a low emittance relativistic electron bunch in a small ({micro}m{sup 3}) interaction volume produces Doppler-upshifted scattered photons with unique characteristics: the energy is tunable in the 5-500 keV range, the angular divergence of the beam is small (mrad), and the pulses are ultrashort (10 fs - 10 ps). Two main paths are currently being followed in laboratories worldwide: high peak brightness, using ultrahigh intensity femtosecond lasers at modest repetition rates, and high average brightness, using superconducting linac and high average power laser technology at MHz repetition rates. Targeted applications range from x-ray protein crystallography and high contrast medical imaging to femtosecond pump-probe and diffraction experiments. More exotic uses of such sources include the {gamma}-{gamma} collider, NIF backlighting, nonlinear Compton scattering, and high-field QED. Theoretical considerations and experimental results will be discussed within this context.

  20. The SPARX Project R&D Activity towards X-rays FEL Sources

    CERN Document Server

    Alesini, David; Bertolucci, Sergio; Biagini, M E; Boni, R; Boscolo, Manuela; Castellano, Michele; Clozza, A; Di Pirro, G; Drago, A; Esposito, A; Ferrario, Massimo; Filippetto, D; Fusco, V; Gallo, A; Ghigo, A; Guiducci, Susanna; Incurvati, M; Ligi, C; Marcellini, F; Migliorati, Mauro; Mostacci, Andrea; Palumbo, Luigi; Pellegrino, L; Preger, Miro; Raimondi, Pantaleo; Ricci, R; Sanelli, C; Serio, Mario; Sgamma, F; Spataro, Bruno; Stecchi, A; Stella, A; Tazzioli, Franco; Vaccarezza, Cristina; Vescovi, Mario; Vicario, C

    2004-01-01

    SPARX is an evolutionary project proposed by a collaboration among ENEA-INFN-CNR-Università di Roma Tor Vergata aiming at the construction of a FEL-SASE X-ray source in the Tor Vergata Campus. The first phase of the SPARX project, funded by Government Agencies, will be focused on the R&D activity on critical components and techniques for future X-ray facilities. The R&D plans for the FEL source will be developped along two lines: (a) use of the SPARC high brightness photo-injector to develop experimental test on RF compression techniques and other beam physics issues, like emittance degradation in magnetic compressors due to CSR; (b) development of new undulator design concepts and up-grading of the FEL SPARC source to enhance the non linear harmonic generation mechanism, design and test of e-beam conditioning, prebunching and seeding. A parallel program will be aimed at the development of high repetition rate S-band gun, high Quantum Efficiency cathodes, high gradient X-band RF acceleratin...

  1. Compton Scattering and its Applications:. the Pleiades Femtosecond X-Ray Source at LLNL

    Science.gov (United States)

    Hartemann, F. V.; Brown, W. J.; Anderson, S. G.; Barty, C. P. J.; Betts, S. M.; Booth, R.; Crane, J. K.; Cross, R. R.; Fittinghoff, D. N.; Gibson, D. J.; Kuba, J.; Rupp, B.; Tremaine, A. M.; Springer, P. T.

    2004-10-01

    Remarkable developments in critical technologies including terawatt-class lasers using chirped-pulse amplification, high brightness photoinjectors, high-gradient accelerators, and superconducting linacs make it possible to design and operate compact, tunable, subpicosecond Compton scattering x-ray sources with a wide variety of applications. In such novel radiation sources, the collision between a femtosecond laser pulse and a low emittance relativistic electron bunch in a small (μm3) interaction volume produces Doppler-upshifted scattered photons with unique characteristics: the energy is tunable in the 5-500 keV range, the angular divergence of the beam is small (mrad), and the pulses are ultrashort (10 fs - 10 ps). Two main paths are currently being followed in laboratories worldwide: high peak brightness, using ultrahigh intensity femtosecond lasers at modest repetition rates, and high average brightness, using superconducting linac and high average power laser technology at MHz repetition rates. Targeted applications range from x-ray protein crystallography and high contrast medical imaging to femtosecond pump-probe and diffraction experiments. More exotic uses of such sources include the γ-γ collider, NIF backlighting, nonlinear Compton scattering, and high-field QED. Theoretical considerations and experimental results will be discussed within this context.

  2. Uhuru observations of 4U 1608-52 - The 'steady' X-ray source associated with the X-ray burst source in Norma

    Science.gov (United States)

    Tananbaum, H.; Chaisson, L. J.; Forman, W.; Jones, C.; Matilsky, T. A.

    1976-01-01

    Data are presented for the X-ray source 4U 1608-52, summarizing its light curve, location, and spectral parameters. Evidence is presented showing that this source is the 'steady' X-ray counterpart of the X-ray burst source in Norma. The spectrum of the 'steady' source is compared with the spectrum observed during two bursts, and it is noted that there is substantially more low-energy absorption during the bursts. The 'steady' source spectral data are used to examine the optical data, and it is concluded that if the X-ray spectrum is thermal, then a globular-cluster counterpart probably would have been detected (whereas none has been). Further X-ray and optical observations are suggested for this source, since an optical identification may be central in determining whether all X-ray bursts have a common origin and if this origin requires a globular-cluster environment.

  3. Uhuru observations of 4U 1608-52 - The 'steady' X-ray source associated with the X-ray burst source in Norma

    Science.gov (United States)

    Tananbaum, H.; Chaisson, L. J.; Forman, W.; Jones, C.; Matilsky, T. A.

    1976-01-01

    Data are presented for the X-ray source 4U 1608-52, summarizing its light curve, location, and spectral parameters. Evidence is presented showing that this source is the 'steady' X-ray counterpart of the X-ray burst source in Norma. The spectrum of the 'steady' source is compared with the spectrum observed during two bursts, and it is noted that there is substantially more low-energy absorption during the bursts. The 'steady' source spectral data are used to examine the optical data, and it is concluded that if the X-ray spectrum is thermal, then a globular-cluster counterpart probably would have been detected (whereas none has been). Further X-ray and optical observations are suggested for this source, since an optical identification may be central in determining whether all X-ray bursts have a common origin and if this origin requires a globular-cluster environment.

  4. Mechanical design and fabrication of the VHF-gun, the Berkeley normal-conducting continuous-wave high-brightness electron source

    Science.gov (United States)

    Wells, R. P.; Ghiorso, W.; Staples, J.; Huang, T. M.; Sannibale, F.; Kramasz, T. D.

    2016-02-01

    A high repetition rate, MHz-class, high-brightness electron source is a key element in future high-repetition-rate x-ray free electron laser-based light sources. The VHF-gun, a novel low frequency radio-frequency gun, is the Lawrence Berkeley National Laboratory (LBNL) response to that need. The gun design is based on a normal conducting, single cell cavity resonating at 186 MHz in the VHF band and capable of continuous wave operation while still delivering the high accelerating fields at the cathode required for the high brightness performance. The VHF-gun was fabricated and successfully commissioned in the framework of the Advanced Photo-injector EXperiment, an injector built at LBNL to demonstrate the capability of the gun to deliver the required beam quality. The basis for the selection of the VHF-gun technology, novel design features, and fabrication techniques are described.

  5. Mechanical design and fabrication of the VHF-gun, the Berkeley normal-conducting continuous-wave high-brightness electron source.

    Science.gov (United States)

    Wells, R P; Ghiorso, W; Staples, J; Huang, T M; Sannibale, F; Kramasz, T D

    2016-02-01

    A high repetition rate, MHz-class, high-brightness electron source is a key element in future high-repetition-rate x-ray free electron laser-based light sources. The VHF-gun, a novel low frequency radio-frequency gun, is the Lawrence Berkeley National Laboratory (LBNL) response to that need. The gun design is based on a normal conducting, single cell cavity resonating at 186 MHz in the VHF band and capable of continuous wave operation while still delivering the high accelerating fields at the cathode required for the high brightness performance. The VHF-gun was fabricated and successfully commissioned in the framework of the Advanced Photo-injector EXperiment, an injector built at LBNL to demonstrate the capability of the gun to deliver the required beam quality. The basis for the selection of the VHF-gun technology, novel design features, and fabrication techniques are described.

  6. Automatic classification of time-variable X-ray sources

    CERN Document Server

    Lo, Kitty K; Murphy, Tara; Gaensler, B M

    2014-01-01

    To maximize the discovery potential of future synoptic surveys, especially in the field of transient science, it will be necessary to use automatic classification to identify some of the astronomical sources. The data mining technique of supervised classification is suitable for this problem. Here, we present a supervised learning method to automatically classify variable X-ray sources in the second \\textit{XMM-Newton} serendipitous source catalog (2XMMi-DR2). Random Forest is our classifier of choice since it is one of the most accurate learning algorithms available. Our training set consists of 873 variable sources and their features are derived from time series, spectra, and other multi-wavelength contextual information. The 10-fold cross validation accuracy of the training data is ${\\sim}$97% on a seven-class data set. We applied the trained classification model to 411 unknown variable 2XMM sources to produce a probabilistically classified catalog. Using the classification margin and the Random Forest der...

  7. Flat Field Anomalies in an X-ray CCD Camera Measured Using a Manson X-ray Source

    Energy Technology Data Exchange (ETDEWEB)

    M. J. Haugh and M. B. Schneider

    2008-10-31

    The Static X-ray Imager (SXI) is a diagnostic used at the National Ignition Facility (NIF) to measure the position of the X-rays produced by lasers hitting a gold foil target. The intensity distribution taken by the SXI camera during a NIF shot is used to determine how accurately NIF can aim laser beams. This is critical to proper NIF operation. Imagers are located at the top and the bottom of the NIF target chamber. The CCD chip is an X-ray sensitive silicon sensor, with a large format array (2k x 2k), 24 μm square pixels, and 15 μm thick. A multi-anode Manson X-ray source, operating up to 10kV and 10W, was used to characterize and calibrate the imagers. The output beam is heavily filtered to narrow the spectral beam width, giving a typical resolution E/ΔE≈10. The X-ray beam intensity was measured using an absolute photodiode that has accuracy better than 1% up to the Si K edge and better than 5% at higher energies. The X-ray beam provides full CCD illumination and is flat, within ±1% maximum to minimum. The spectral efficiency was measured at 10 energy bands ranging from 930 eV to 8470 eV. We observed an energy dependent pixel sensitivity variation that showed continuous change over a large portion of the CCD. The maximum sensitivity variation occurred at 8470 eV. The geometric pattern did not change at lower energies, but the maximum contrast decreased and was not observable below 4 keV. We were also able to observe debris, damage, and surface defects on the CCD chip. The Manson source is a powerful tool for characterizing the imaging errors of an X-ray CCD imager. These errors are quite different from those found in a visible CCD imager.

  8. Patchy Accretion Disks in Ultraluminous X-ray Sources

    CERN Document Server

    Miller, J M; Barret, D; Harrison, F A; Fabian, A C; Webb, N A; Walton, D J; Rana, V

    2014-01-01

    The X-ray spectra of the most extreme ultra-luminous X-ray sources -- those with L > 1 E+40 erg/s -- remain something of a mystery. Spectral roll-over in the 5-10 keV band was originally detected in in the deepest XMM-Newton observations of the brightest sources; this is confirmed in subsequent NuSTAR spectra. This emission can be modeled via Comptonization, but with low electron temperatures (kT_e ~ 2 keV) and high optical depths (tau ~ 10) that pose numerous difficulties. Moreover, evidence of cooler thermal emission that can be fit with thin disk models persists, even in fits to joint XMM-Newton and NuSTAR observations. Using NGC 1313 X-1 as a test case, we show that a patchy disk with a multiple temperature profile may provide an excellent description of such spectra. In principle, a number of patches within a cool disk might emit over a range of temperatures, but the data only require a two-temperature profile plus standard Comptonization, or three distinct blackbody components. A mechanism such as the p...

  9. Two-dimensional X-ray focusing by off-axis grazing incidence phase Fresnel zone plate on the laboratory X-ray source

    Science.gov (United States)

    Grigoriev, Maxim; Fakhrtdinov, Rashid; Irzhak, Dmitry; Firsov, Alexander; Firsov, Anatoly; Svintsov, Alexander; Erko, Alexey; Roshchupkin, Dmitry

    2017-02-01

    The results of studying a two-dimensional X-ray focusing by an off-axis grazing incidence phase Fresnel zone plate on the laboratory X-ray source are presented. This optics enables obtaining a focal spot of 2 μm on the laboratory X-ray source with a focusing efficiency of 30% at a high signal/noise ratio.

  10. Modification of the TASMIP x-ray spectral model for the simulation of microfocus x-ray sources

    Energy Technology Data Exchange (ETDEWEB)

    Sisniega, A.; Vaquero, J. J., E-mail: juanjose.vaquero@uc3m.es [Departamento de Bioingeniería e Ingeniería Aeroespacial, Universidad Carlos III de Madrid, Madrid ES28911 (Spain); Instituto de Investigación Sanitaria Gregorio Marañón, Madrid ES28007 (Spain); Desco, M. [Departamento de Bioingeniería e Ingeniería Aeroespacial, Universidad Carlos III de Madrid, Madrid ES28911 (Spain); Instituto de Investigación Sanitaria Gregorio Marañón, Madrid ES28007 (Spain); Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid ES28029 (Spain)

    2014-01-15

    Purpose: The availability of accurate and simple models for the estimation of x-ray spectra is of great importance for system simulation, optimization, or inclusion of photon energy information into data processing. There is a variety of publicly available tools for estimation of x-ray spectra in radiology and mammography. However, most of these models cannot be used directly for modeling microfocus x-ray sources due to differences in inherent filtration, energy range and/or anode material. For this reason the authors propose in this work a new model for the simulation of microfocus spectra based on existing models for mammography and radiology, modified to compensate for the effects of inherent filtration and energy range. Methods: The authors used the radiology and mammography versions of an existing empirical model [tungsten anode spectral model interpolating polynomials (TASMIP)] as the basis of the microfocus model. First, the authors estimated the inherent filtration included in the radiology model by comparing the shape of the spectra with spectra from the mammography model. Afterwards, the authors built a unified spectra dataset by combining both models and, finally, they estimated the parameters of the new version of TASMIP for microfocus sources by calibrating against experimental exposure data from a microfocus x-ray source. The model was validated by comparing estimated and experimental exposure and attenuation data for different attenuating materials and x-ray beam peak energy values, using two different x-ray tubes. Results: Inherent filtration for the radiology spectra from TASMIP was found to be equivalent to 1.68 mm Al, as compared to spectra obtained from the mammography model. To match the experimentally measured exposure data the combined dataset required to apply a negative filtration of about 0.21 mm Al and an anode roughness of 0.003 mm W. The validation of the model against real acquired data showed errors in exposure and attenuation in

  11. Volume-scalable high-brightness three-dimensional visible light source

    Science.gov (United States)

    Subramania, Ganapathi; Fischer, Arthur J; Wang, George T; Li, Qiming

    2014-02-18

    A volume-scalable, high-brightness, electrically driven visible light source comprises a three-dimensional photonic crystal (3DPC) comprising one or more direct bandgap semiconductors. The improved light emission performance of the invention is achieved based on the enhancement of radiative emission of light emitters placed inside a 3DPC due to the strong modification of the photonic density-of-states engendered by the 3DPC.

  12. LIGHT SOURCE: Spot size diagnostics for flash radiographic X-ray sources at LAPA

    Science.gov (United States)

    Li, Cheng-Gang; Li, Qin; Shi, Jin-Shui; Deng, Jian-Jun

    2009-06-01

    Spot size is one of the parameters to characterize the performance of a radiographic X-ray source. It determines the degree of blurring due to magnification directly. In recent years, a variety of measurement methods have been used to diagnose X-ray spot size at Laboratory of Accelerator Physics and Application (LAPA). Computer simulations and experiments showed that using a rolled-edge to measure the spot size are more accurate, and the intensity distribution of X-ray source was obtained by a device with a square aperture. Experimental and simulation results on a flash X-ray source at our laboratory are presented and discussed in this paper. In addition, a new method for time resolved diagnostics of X-ray spot size is introduced too.

  13. Carbon nanotube based X-ray sources: Applications in pre-clinical and medical imaging

    Science.gov (United States)

    Lee, Yueh Z.; Burk, Laurel; Wang, Ko-Han; Cao, Guohua; Lu, Jianping; Zhou, Otto

    2011-08-01

    Field emission offers an alternate method of electron production for Bremsstrahlung based X-ray tubes. Carbon nanotubes (CNTs) serve as very effective field emitters, allowing them to serve as electron sources for X-ray sources, with specific advantages over traditional thermionic tubes. CNT derived X-ray sources can create X-ray pulses of any duration and frequency, gate the X-ray pulse to any source and allow the placement of many sources in close proximity.We have constructed a number of micro-CT systems based on CNT X-ray sources for applications in small animal imaging, specifically focused on the imaging of the heart and lungs. This paper offers a review of the pre-clinical applications of the CNT based micro-CT that we have developed. We also discuss some of the current and potential clinical applications of the CNT X-ray sources.

  14. Chilled disks in ultraluminous X-ray sources

    Science.gov (United States)

    Soria, Roberto; Kuncic, Zdenka; Gonçalves, Anabela C.

    2007-04-01

    The "soft-excess" component fitted to the X-ray spectra of many ultraluminous X-ray sources (ULXs) remains a controversial finding, which may reveal fundamental information either on the black hole (BH) mass or on the state of the accretion flow. In the simplest model, it was explained as thermal emission from a cool accretion disk around an intermediate-mass BH (about 1000 solar masses). We argue that this scenario is highly implausible, and discuss and compare the two most likely alternatives. 1) The soft-excess does come from a cool disk; however, the temperature is low not because of a high BH mass but because most of the accretion power is drained from the inner disk via magnetic torques, and channelled into jets and outflows ("chilled disk" scenario). Using a phenomenological model, we infer that ULXs contain BHs of about 50 solar masses accreting gas at about 10 times their Eddington rate. 2) The soft excess is in fact a soft deficit, if the power-law continuum is properly fitted. Such broad absorption features are caused by smeared absorption lines in fast, highly ionized outflows. This scenario has already been successfully applied to the soft excess in AGN. If so, this spectral feature reveals details of disk outflows,but is unrelated to the BH mass.

  15. X-ray detectors at the Linac Coherent Light Source.

    Science.gov (United States)

    Blaj, Gabriel; Caragiulo, Pietro; Carini, Gabriella; Carron, Sebastian; Dragone, Angelo; Freytag, Dietrich; Haller, Gunther; Hart, Philip; Hasi, Jasmine; Herbst, Ryan; Herrmann, Sven; Kenney, Chris; Markovic, Bojan; Nishimura, Kurtis; Osier, Shawn; Pines, Jack; Reese, Benjamin; Segal, Julie; Tomada, Astrid; Weaver, Matt

    2015-05-01

    Free-electron lasers (FELs) present new challenges for camera development compared with conventional light sources. At SLAC a variety of technologies are being used to match the demands of the Linac Coherent Light Source (LCLS) and to support a wide range of scientific applications. In this paper an overview of X-ray detector design requirements at FELs is presented and the various cameras in use at SLAC are described for the benefit of users planning experiments or analysts looking at data. Features and operation of the CSPAD camera, which is currently deployed at LCLS, are discussed, and the ePix family, a new generation of cameras under development at SLAC, is introduced.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-09-15

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

  17. Synchrotron x-ray sources and new opportunities in the soil and environmental sciences

    Energy Technology Data Exchange (ETDEWEB)

    Schulze, D. (Purdue Univ., Lafayette, IN (USA)); Anderson, S. (Michigan State Univ., East Lansing, MI (USA)); Mattigod, S. (Pacific Northwest Lab., Richland, WA (USA))

    1990-07-01

    This report contains the following papers: characteristics of the advanced photon source and comparison with existing synchrotron facilities; x-ray absorption spectroscopy: EXAFS and XANES -- A versatile tool to study the atomic and electronic structure of materials; applications of x-ray spectroscopy and anomalous scattering experiments in the soil and environmental sciences; X-ray fluorescence microprobe and microtomography.

  18. Electron cyclotron resonance ion source plasma characterization by X-ray spectroscopy and X-ray imaging

    Energy Technology Data Exchange (ETDEWEB)

    Mascali, David, E-mail: davidmascali@lns.infn.it; Castro, Giuseppe; Celona, Luigi; Neri, Lorenzo; Gammino, Santo [INFN–Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); Biri, Sándor; Rácz, Richárd; Pálinkás, József [Institute for Nuclear Research (Atomki), Hungarian Academy of Sciences, Bem tér 18/c, H-4026 Debrecen (Hungary); Caliri, Claudia [INFN–Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); Università degli Studi di Catania, Dip.to di Fisica e Astronomia, via Santa Sofia 64, 95123 Catania (Italy); Romano, Francesco Paolo [INFN–Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); CNR, Istituto per i Beni Archeologici e Monumentali, Via Biblioteca 4, 95124 Catania (Italy); Torrisi, Giuseppe [INFN–Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); Università Mediterranea di Reggio Calabria, DIIES, Via Graziella, I-89100 Reggio Calabria (Italy)

    2016-02-15

    An experimental campaign aiming to investigate electron cyclotron resonance (ECR) plasma X-ray emission has been recently carried out at the ECRISs—Electron Cyclotron Resonance Ion Sources laboratory of Atomki based on a collaboration between the Debrecen and Catania ECR teams. In a first series, the X-ray spectroscopy was performed through silicon drift detectors and high purity germanium detectors, characterizing the volumetric plasma emission. The on-purpose developed collimation system was suitable for direct plasma density evaluation, performed “on-line” during beam extraction and charge state distribution characterization. A campaign for correlating the plasma density and temperature with the output charge states and the beam intensity for different pumping wave frequencies, different magnetic field profiles, and single-gas/gas-mixing configurations was carried out. The results reveal a surprisingly very good agreement between warm-electron density fluctuations, output beam currents, and the calculated electromagnetic modal density of the plasma chamber. A charge-coupled device camera coupled to a small pin-hole allowing X-ray imaging was installed and numerous X-ray photos were taken in order to study the peculiarities of the ECRIS plasma structure.

  19. Multiple station beamline at an undulator x-ray source

    DEFF Research Database (Denmark)

    Als-Nielsen, J.; Freund, A.K.; Grübel, G.

    1994-01-01

    -ray transparent monochromator crystals. Diamond in particular is an attractive monochromator as it is rather X-ray transparent and can be fabricated to a high degree of crystal perfection. Moreover, it has a very high heat conductivity and a rather small thermal expansion so the beam X-ray heat load problem...

  20. Time series analysis of bright galactic X-ray sources

    DEFF Research Database (Denmark)

    Priedhorsky, W. C.; Brandt, Søren; Lund, Niels

    1995-01-01

    We analyze 70 to 110 day data sets from eight bright galactic X-ray binaries observed by WATCH/Eureca, in search of periodic variations. We obtain new epochs for the orbital variation of Cyg X-3 and 4U 1700-37, and confirmation of a dip in Cyg X-1 at superior conjunction of the X-ray star. No evi...

  1. Time-resolved X-ray diffraction with accelerator- and laser-plasma-based X-ray sources

    Energy Technology Data Exchange (ETDEWEB)

    Nicoul, Matthieu

    2010-09-01

    Femtosecond X-ray pulses are a powerful tool to investigate atomic motions triggered by femtosecond pump pulses. This thesis is dedicated to the production of such pulses and their use in optical pump - X-ray probe measurement. This thesis describes the laser-plasma-based sources available at the University of Duisburg-Essen. Part of it consists of the description of the design, built-up and characterization of a new ''modular'' X-ray source dedicated to optimize the X-ray flux onto the sample under investigation. The acoustic wave generation in femtosecond optically excited semiconductor (gallium arsenide) and metal (gold) was performed using the sources of the University of Duisburg-Essen. The physical answer of the material was modeled by a simple strain model for the semiconductor, pressure model for the metal, in order to gain information on the interplay of the electronic and thermal pressures rising after excitation. Whereas no reliable information could be obtain in gallium arsenide (principally due to the use of a bulk), the model for gold achieved very good agreement, providing useful information. The relaxation time of the electron to lattice energy was found to be (5.0{+-}0.3) ps, and the ratio of the Grueneisen parameters was found to be {gamma}{sub e} / {gamma}{sub i} = (0.5{+-}0.1). This thesis also describes the Sub-Picosecond Pulse Source (SPPS) which existed at the (formally) Stanford Linear Accelerator Center, an accelerator-based X-ray source, and two measurements performed with it. The first one is the detailed investigation of the phonon softening of the A{sub 1g} mode launch in bismuth upon fluence excitation. Detailed information concerning the new equilibrium position and phonon frequency were obtained over extended laser pump fluences. The second measurement concerned the study of the liquid phase dynamics in a newly formed liquid phase following ultrafast melting in indium antimonide. The formation of the liquid phase

  2. A proposal for a collecting mirror assembly for large divergence x-ray sources.

    Science.gov (United States)

    Ichimaru, Satoshi; Hatayama, Masatoshi; Ohchi, Tadayuki; Oku, Satoshi

    2014-11-01

    We propose a new type of collecting mirror assembly (CMA) for x rays, which will enable us to build a powerful optical system for collecting x rays from large divergence sources. The CMA consists of several mirror sections connected in series. The angle of each section is designed so that the x rays reflected from it are parallel to the x rays directly incident on the following sections. A simplified CMA structure is designed and applied to the Al-Kα emission line. It is estimated that by using the CMA the number of x rays detected could be increased by a factor of about 2.5.

  3. A carbon nanotube field emission multipixel x-ray array source for microradiotherapy application

    OpenAIRE

    Wang, Sigen; Calderon, Xiomara; Peng, Rui; Schreiber, Eric C.; Zhou, Otto; Chang, Sha

    2011-01-01

    The authors report a carbon nanotube (CNT) field emission multipixel x-ray array source for microradiotherapy for cancer research. The developed multipixel x-ray array source has 50 individually controllable pixels and it has several distinct advantages over other irradiation source including high-temporal resolution (millisecond level), the ability to electronically shape the form, and intensity distribution of the radiation fields. The x-ray array was generated by a CNT cathode array (5×10)...

  4. Performance of the Cygnus X-ray Source

    Science.gov (United States)

    Smith, John R.; Carlson, Randolph; Fulton, Robert D.; Altes, R.; Carboni, V.; Chavez, Jacob R.; Corcoran, P.; Coulter, William L.; Douglas, J.; Droemer, D.; Gibson, William A.; Helvin, Thomas B.; Henderson, David J.; Johnson, David L.; Maenchen, John E.; Mitton, Charlas V.; Molina, Isidro; Nishimoto, H.; Ormond, Eugene C.; Ortega, Paul A.; Quicksilver, Robert J.; Ridlon, Rae N.; Rose, Evan A.; Scholfield, David W.; Smith, I.; Valerio, Antonio R.; White, R.

    2002-12-01

    Cygnus is a radiographic x-ray source developed for support of the Sub-Critical Experiments Program at the Nevada Test Site. Major requirements for this application are: a dramatically reduced spot size as compared to both Government Laboratory and existing commercial alternatives, layout flexibility, and reliability. Cygnus incorporates proven pulsed power technology (Marx Generator, Pulse Forming Line, Water Transmission Line, and Inductive Voltage Adder sub-components) to drive a high voltage vacuum diode. In the case of Cygnus, a relatively new approach (the rod pinch diode [1]) is employed to achieve a small source diameter. Design specifications are: 2.25 MeV endpoint energy, 3 rads dose at 1 meter. The pulsed power and system architecture design plan has been previously presented [2]. The first set of Cygnus shots were geared to verification of electrical parameters and, therefore, used a large area diode configuration offering increased shot rate as compared to that of the rod pinch diode. In this paper we present results of initial rod pinch operation in terms of electrical and radiation parameters.

  5. Nature of the Extreme Ultraluminous X-ray Sources

    CERN Document Server

    Wiktorowicz, Grzegorz; Sadowski, Aleksander; Belczynski, Krzysztof

    2015-01-01

    In this proof-of-concept study we demonstrate how a binary system can easily form an extreme ULX source with the X-ray luminosity of L_x > 10^42 erg/s. Formation efficiencies and lifetimes of such objects are high enough to potentially explain all observed extreme ULXs. These systems are not only limited to binaries with stellar-origin black hole accretors. Noteworthy, we have also identified such objects with neutron stars. Typically, a 10 Msun black hole is fed by a massive (~10 Msun) Hertzsprung gap donor with Roche lobe overflow rate of ~10^-3 Msun/yr (~2600 Mdot_Edd). For neutron star systems the typical donors are evolved low-mass (~2 Msun) helium stars with Roche lobe overflow rate of ~10^-2 Msun/yr. We base our study purely on the available Roche lobe overflow rate in a binary system and show that if only even a small fraction (>10^-3) of the overflow reaches the BH, the source will be super-Eddington. Our study does not prove that any particular extreme ULX (e.g., HLX-1) is a regular binary system wi...

  6. Spectral variability of ultraluminous X-ray sources

    CERN Document Server

    Kajava, Jari J E

    2008-01-01

    We study spectral variability of 11 ultraluminous X-ray sources (ULX) using archived XMM-Newton and Chandra observations. We use three models to describe the observed spectra; a power-law, a multi-colour disk (MCD) and a combination of these two models. We find that out of the 11 ULXs in our sample, 7 ULXs show a correlation between the luminosity and the photon index Gamma (hereafter L-Gamma correlation). Furthermore, out of the 7 ULXs that have the L-Gamma correlation, 4 ULXs also show spectral pivoting in the observed energy band. We also find that two ULXs show an L-Gamma anti-correlation. The spectra of 4 ULXs in the sample can be adequately fitted with a MCD model. We compare these sources to known black hole binaries (BHB) and find that they follow similar paths in their luminosity-temperature (hereafter L-T) diagrams. Finally we show that the 'soft excess' reported for many of these ULXs at 0.2 keV seem to follow a trend L \\propto T^{-4} when modeled with a power-law plus a 'cool' MCD model. This is c...

  7. Spectral variability of ultraluminous X-ray sources

    CERN Document Server

    Kajava, Jari J E

    2009-01-01

    We study spectral variability of 11 ultraluminous X-ray sources (ULX) using archived XMM-Newton and Chandra observations. We use three models to describe the observed spectra: a power-law, a multi-colour disc (MCD) and a combination of these two models. We find that 7 ULXs show a correlation between the luminosity Lx and the photon index Gamma. Furthermore, 4 out of these 7 ULXs also show spectral pivoting in the observed energy band. We also find that two ULXs show an Lx-Gamma anti-correlation. The spectra of 4 ULXs in the sample can be adequately fitted with a MCD model. We compare these sources to known black hole binaries (BHB) and find that they follow similar paths in their luminosity-temperature diagrams. Finally we show that the `soft excess' reported for many of these ULXs at about 0.2 keV seems to roughly follow a trend Lsoft \\propto T^{-3.5} when modelled with a power-law plus a `cool' MCD model. This is contrary to the L \\propto T^4 relation that is expected from theory and what is seen for many a...

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

    Science.gov (United States)

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

    2007-01-01

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

  9. Tabletop Ultrabright Kiloelectronvolt X-Ray Sources from Xe and Kr Hollow Atom States

    Science.gov (United States)

    Sankar, Poopalasingam

    Albert Einstein, the father of relativity, once said, "Look deep into nature, and then you will understand everything better". Today available higher resolution tabletop tool to look deep into matters and living thing is an x-ray source. Although the available tabletop x-rays sources of the 20th century, such as the ones used for medical or dental x-rays are tremendously useful for medical diagnostics and industry, a major disadvantage is that they have low quality skillful brightness, which limits its resolution and accuracy. In the other hand, x-ray free-electrons laser (XFEL) and synchrotron radiation sources provided extreme bright x-rays. However, number of applications of XFEL and synchrotron such as medical and industrials, has been hampered by their size, complexity, and cost. This has set a goal of demonstrating x-ray source with enough brightness for potential applications in an often-called tabletop compact x-ray source that could be operated in university laboratory or hospitals. We have developed two tabletop ultrabright keV x-ray sources, one from a Xe hollow-atom states and the other one from Kr hollow-atom stares with a unique characteristic that makes them complementary to currently-available extreme-light sources; XFEL, and synchrotron x-ray source. Upgraded tabletop ultra-fast KrF* pump-laser interacts with target rare-gas clusters and produces hollow-atom states, which later coherently collapse to the empty inner-shell and thereby generate keV x-ray radiation. The KrF* pump-laser beam is self-focused and forms a self-channel to guide the generated x-ray radiation in the direction of the pump-laser beam to produce directed x-ray beam. Xe (M) x-ray source operates at 1.2-1.6 nm wavelength while the Kr(L) x-ray source operates in 600-800 pm wavelength. System is mounted upon 3 optical-tables (5´x12´) with two KrF amplifiers at a repetition rate of 0.1 Hz. A lower bound for brightness value for both Xe and Kr x-ray sources is 1026 photons s-1mm-2

  10. X-ray imaging detectors for synchrotron and XFEL sources

    Directory of Open Access Journals (Sweden)

    Takaki Hatsui

    2015-05-01

    Full Text Available Current trends for X-ray imaging detectors based on hybrid and monolithic detector technologies are reviewed. Hybrid detectors with photon-counting pixels have proven to be very powerful tools at synchrotrons. Recent developments continue to improve their performance, especially for higher spatial resolution at higher count rates with higher frame rates. Recent developments for X-ray free-electron laser (XFEL experiments provide high-frame-rate integrating detectors with both high sensitivity and high peak signal. Similar performance improvements are sought in monolithic detectors. The monolithic approach also offers a lower noise floor, which is required for the detection of soft X-ray photons. The link between technology development and detector performance is described briefly in the context of potential future capabilities for X-ray imaging detectors.

  11. X-ray imaging detectors for synchrotron and XFEL sources.

    Science.gov (United States)

    Hatsui, Takaki; Graafsma, Heinz

    2015-05-01

    Current trends for X-ray imaging detectors based on hybrid and monolithic detector technologies are reviewed. Hybrid detectors with photon-counting pixels have proven to be very powerful tools at synchrotrons. Recent developments continue to improve their performance, especially for higher spatial resolution at higher count rates with higher frame rates. Recent developments for X-ray free-electron laser (XFEL) experiments provide high-frame-rate integrating detectors with both high sensitivity and high peak signal. Similar performance improvements are sought in monolithic detectors. The monolithic approach also offers a lower noise floor, which is required for the detection of soft X-ray photons. The link between technology development and detector performance is described briefly in the context of potential future capabilities for X-ray imaging detectors.

  12. Miniature X-ray Source for Planetary Exploration Instruments Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of the proposed work is to develop a design model for a CNT cold cathode, low power, passively cooled, and grounded-anode X-ray tube that is compatible...

  13. X-ray imaging detectors for synchrotron and XFEL sources

    OpenAIRE

    Takaki Hatsui; Heinz Graafsma

    2015-01-01

    Current trends for X-ray imaging detectors based on hybrid and monolithic detector technologies are reviewed. Hybrid detectors with photon-counting pixels have proven to be very powerful tools at synchrotrons. Recent developments continue to improve their performance, especially for higher spatial resolution at higher count rates with higher frame rates. Recent developments for X-ray free-electron laser (XFEL) experiments provide high-frame-rate integrating detectors with both high sensitivit...

  14. The BeppoSAX High Energy Large Area Survey. IV. On the soft X-ray properties of the hard X-ray-selected HELLAS sources

    CERN Document Server

    Vignali, C; Fiore, F; La Franca, F

    2001-01-01

    We present a comprehensive study of the soft X-ray properties of the BeppoSAX High-Energy Large Area Survey (HELLAS) sources. A large fraction (about 2/3) of the hard X-ray selected sources is detected by ROSAT. The soft X-ray colors for many of these objects, along with the 0.5-2 keV flux upper limits for those undetected in the ROSAT band, do imply the presence of absorption. The comparison with the ROSAT Deep Survey sources indicates that a larger fraction of absorbed objects among the HELLAS sources is present, in agreement with their hard X-ray selection and the predictions of the X-ray background synthesis models. Another striking result is the presence of a soft (additional) X-ray component in a significant fraction of absorbed objects.

  15. Infrared Counterparts to Chandra X-Ray Sources in the Antennae

    CERN Document Server

    Clark, D M; Brandl, B R; Wilson, J C; Carson, J C; Henderson, C P; Hayward, T L; Barry, D J; Ptak, A F; Colbert, E J M

    2006-01-01

    We use deep J and Ks images of the Antennae (NGC 4038/9) obtained with WIRC on the Palomar 200-inch telescope, together with the Chandra X-ray source list of Zezas et al. (2002a), to search for IR counterparts to X-ray point sources. We establish an X-ray/IR astrometric frame tie with 0.5" rms residuals over a \\~4.3' field. We find 13 ``strong'' IR counterparts brighter than Ks = 17.8 mag and < 1.0" from X-ray sources, and an additional 6 ``possible'' IR counterparts between 1.0" and 1.5" from X-ray sources. The surface density of IR sources near the X-ray sources suggests only ~2 of the ``strong'' counterparts and ~3 of the ``possible'' counterparts are chance superpositions of unrelated objects. Comparing both strong and possible IR counterparts to our photometric study of ~220 Antennae, IR clusters, we find the IR counterparts to X-ray sources are \\~1.2 mag more luminous in Ks than average non-X-ray clusters. We also note that the X-ray/IR matches are concentrated in the spiral arms and ``overlap'' regi...

  16. A radio monitoring survey of ultra-luminous X-ray sources

    NARCIS (Netherlands)

    Körding, E.; Colbert, E.; Falcke, H.D.E.

    2005-01-01

    We present the results of a radio monitoring campaign to search for radio emission from nearby ultra-luminous X-ray sources (ULXs). These sources are bright off-nuclear X-ray point sources with luminosities exceeding LX > 1039 erg s-1. A well-defined sample of the 9

  17. The X-ray eclipse geometry of the super-soft X-ray source CAL 87

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, T.; Lopes de Oliveira, R. [Departamento de Física, Universidade Federal de Sergipe, Av. Marechal Rondon s/n, 49100-000 São Cristóvão, SE (Brazil); Borges, B. W., E-mail: tribeiro@ufs.br, E-mail: rlopes@ufs.br, E-mail: bernardo@astro.ufsc.br [Universidade Federal de Santa Catarina, Campus Araranguá, 88905-120 Araranguá, SC (Brazil)

    2014-09-01

    We explore XMM-Newton observations of the eclipsing super-soft X-ray source CAL 87 in order to map the accretion structures of the system. Indirect imaging techniques were applied in X-ray light curves to provide eclipse maps. The surface brightness distribution exhibits an extended and symmetric emission, and a feature is revealed from the hardest X-rays that is likely due to a bright spot. A rate of P-dot =(+6±2)×10{sup −10} for changes in the orbital period of the system was derived from the eclipses. There is no significant variation of the emission lines even during eclipses, arguing that the lines are formed in an extended region. The continuum emission dominates the decrease in flux that is observed during eclipses. The O VIII Lyα line reveals a broadening velocity that is estimated to be 365{sub −69}{sup +65} km s{sup –1} (at 1σ), marginal evidence for asymmetry in its profile, and sometimes shows evidence of double-peaked emission. Together, the results support that the wind-driven mass transfer scenario is running in CAL 87.

  18. The scaling of X-ray variability with luminosity in Ultra-luminous X-ray sources

    CERN Document Server

    Gonzalez-Martin, O; Reig, P; Zezas, A

    2010-01-01

    We investigated the relationship between the X-ray variability amplitude and X-ray luminosity for a sample of 14 bright Ultra-luminous X-ray sources (ULXs) with XMM-Newton/EPIC data, and compare it with the well established similar relationship for Active Galactic Nuclei (AGN). We computed the normalised excess variance in the 2-10 keV light curves of these objects and their 2-10 keV band intrinsic luminosity. We also determined model "variability-luminosity" relationships for AGN, under several assumptions regarding their power-spectral shape. We compared these model predictions at low luminosities with the ULX data. The variability amplitude of the ULXs is significantly smaller than that expected from a simple extrapolation of the AGN "variability-luminosity" relationship at low luminosities. We also find evidence for an anti-correlation between the variability amplitude and L(2-10 keV) for ULXs. The shape of this relationship is consistent with the AGN data but only if the ULXs data are shifted by four ord...

  19. The spatial, spectral and polarization properties of solar flare X-ray sources

    CERN Document Server

    Jeffrey, Natasha L S

    2014-01-01

    X-rays are a valuable diagnostic tool for the study of high energy accelerated electrons. Bremsstrahlung X-rays produced by, and directly related to, high energy electrons accelerated during a flare, provide a powerful diagnostic tool for determining both the properties of the accelerated electron distribution, and of the flaring coronal and chromospheric plasmas. This thesis is specifically concerned with the study of spatial, spectral and polarization properties of solar flare X-ray sources via both modelling and X-ray observations using the Ramaty High Energy Solar Spectroscopic Imager (RHESSI). Firstly, a new model is presented, accounting for finite temperature, pitch angle scattering and initial pitch angle injection. This is developed to accurately infer the properties of the acceleration region from the observations of dense coronal X-ray sources. Moreover, examining how the spatial properties of dense coronal X-ray sources change in time, interesting trends in length, width, position, number density ...

  20. A novel high-brightness broadband light-source technology from the VUV to the IR

    Science.gov (United States)

    Horne, Stephen; Smith, Don; Besen, Matthew; Partlow, Matthew; Stolyarov, Daniil; Zhu, Huiling; Holber, William

    2010-04-01

    A novel technology has been developed which enables high-brightness, broadband light output from the VUV to the IR spectral regions. A focused laser is used to sustain a high-pressure xenon discharge inside a bulb, creating a smaller, hotter discharge than can be obtained by using an electrically-driven discharge. This allows for continuous output down to 120 nm wavelength and into the infrared. Application areas include hyperspectral imaging, standoff detection, surveillance, bioanalytical instrumentation, microscopy, and materials studies. Laser-driven optical discharges were first investigated over 30 years ago, providing the initial technical understanding of such discharges. However it took the convergence of two separate elements - the availability of low-cost, high-efficiency CW diode lasers; and a market need for high-brightness, broadband light source - to provide the impetus for further development in this area. Using near-IR CW diode lasers at power levels from 15 W to over 2000 W, we have generated high-pressure xenon discharges having temperatures as high as 10,000 C. The optical brightness of these discharges can be over an order of magnitude higher than those obtainable from the brightest xenon arc lamps, and can be several orders of magnitude brighter than deuterium lamps. Results from modeling of these discharges as well as experimental measurements will be presented.

  1. A SEARCH FOR HYPERLUMINOUS X-RAY SOURCES IN THE XMM-NEWTON SOURCE CATALOG

    Energy Technology Data Exchange (ETDEWEB)

    Zolotukhin, I.; Webb, N. A.; Godet, O.; Barret, D. [CNRS, IRAP, 9 av. Colonel Roche, BP 44346, F-31028 Toulouse cedex 4 (France); Bachetti, M., E-mail: ivan.zolotukhin@irap.omp.eu [INAF/Osservatorio Astronomico di Cagliari, via della Scienza 5, I-09047 Selargius (Italy)

    2016-02-01

    We present a new method to identify luminous off-nuclear X-ray sources in the outskirts of galaxies from large public redshift surveys, distinguishing them from foreground and background interlopers. Using the 3XMM-DR5 catalog of X-ray sources and the SDSS DR12 spectroscopic sample of galaxies, with the help of this off-nuclear cross-matching technique, we selected 98 sources with inferred X-ray luminosities in the range 10{sup 41} < L{sub X} < 10{sup 44} erg s{sup −1}, compatible with hyperluminous X-ray objects (HLX). To validate the method, we verify that it allowed us to recover known HLX candidates such as ESO 243–49 HLX–1 and M82 X–1. From a statistical study, we conservatively estimate that up to 71 ± 11 of these sources may be foreground- or background sources, statistically leaving at least 16 that are likely to be HLXs, thus providing support for the existence of the HLX population. We identify two good HLX candidates and using other publicly available data sets, in particular the VLA FIRST in radio, UKIRT Infrared Deep Sky Survey in the near-infrared, GALEX in the ultraviolet and Canada–France–Hawaii Telescope Megacam archive in the optical, we present evidence that these objects are unlikely to be foreground or background X-ray objects of conventional types, e.g., active galactic nuclei, BL Lac objects, Galactic X-ray binaries, or nearby stars. However, additional dedicated X-ray and optical observations are needed to confirm their association with the assumed host galaxies and thus secure their HLX classification.

  2. The Radiation Dose Determination of the Pulsed X-ray Source

    Science.gov (United States)

    Miloichikova, I.; Stuchebrov, S.; Zhaksybayeva, G.; Wagner, A.

    2014-10-01

    In this paper the radiation dose measurement technique of the pulsed X-ray source RAP-160-5 is described. The dose rate measurement results from the pulsed X-ray beams at the different distance between the pulsed X-ray source focus and the detector obtained with the help of the thermoluminescent detectors DTL-02, the universal dosimeter UNIDOS E equipped with the plane-parallel ionization chamber type 23342, the dosimeter-radiometer DKS-96 and the radiation dosimeter AT 1123 are demonstrated. The recommendations for the dosimetry measurements of the pulsed X-ray generator RAP-160-5 under different radiation conditions are proposed.

  3. A deeper look at the X-ray point source population of NGC 4472

    Science.gov (United States)

    Joseph, T. D.; Maccarone, T. J.; Kraft, R. P.; Sivakoff, G. R.

    2017-10-01

    In this paper we discuss the X-ray point source population of NGC 4472, an elliptical galaxy in the Virgo cluster. We used recent deep Chandra data combined with archival Chandra data to obtain a 380 ks exposure time. We find 238 X-ray point sources within 3.7 arcmin of the galaxy centre, with a completeness flux, FX, 0.5-2 keV = 6.3 × 10-16 erg s-1 cm-2. Most of these sources are expected to be low-mass X-ray binaries. We finding that, using data from a single galaxy which is both complete and has a large number of objects (˜100) below 1038 erg s-1, the X-ray luminosity function is well fitted with a single power-law model. By cross matching our X-ray data with both space based and ground based optical data for NGC 4472, we find that 80 of the 238 sources are in globular clusters. We compare the red and blue globular cluster subpopulations and find red clusters are nearly six times more likely to host an X-ray source than blue clusters. We show that there is evidence that these two subpopulations have significantly different X-ray luminosity distributions. Source catalogues for all X-ray point sources, as well as any corresponding optical data for globular cluster sources, are also presented here.

  4. X-ray Sources and their Optical Counterparts in the Globular Cluster M4

    CERN Document Server

    Bassa, C; Homer, L; Verbunt, F; Gaensler, B M; Lewin, W H G; Anderson, S F; Margon, B; Kaspi, V M; Van der Klis, M; Bassa, Cees; Pooley, David; Homer, Lee; Verbunt, Frank; Gaensler, Bryan M.; Lewin, Walter H. G.; Anderson, Scott F.; Margon, Bruce; Kaspi, Victoria M.; Klis, Michiel van der

    2004-01-01

    We report on the Chandra X-ray Observatory ACIS-S3 imaging observation of the Galactic globular cluster M4 (NGC 6121). We detect 12 X-ray sources inside the core and 19 more within the cluster half-mass radius. The limiting luminosity of this observation is Lx~10e29 erg/sec for sources associated with the cluster, the deepest X-ray observation of a globular cluster to date. We identify 6 X-ray sources with known objects and use ROSAT observations to show that the brightest X-ray source is variable. Archival data from the Hubble Space Telescope allow us to identify optical counterparts to 16 X-ray sources. Based on the X-ray and optical properties of the identifications and the information from the literature, we classify two (possibly three) sources as cataclysmic variables, one X-ray source as a millisecond pulsar and 12 sources as chromospherically active binaries. Comparison of M4 with 47 Tuc and NGC 6397 suggests a scaling of the number of active binaries in these clusters with the cluster (core) mass.

  5. A dedicated synchrotron light source for ultrafast x-ray science

    Energy Technology Data Exchange (ETDEWEB)

    Corlett, J.; DeSantis, S.; Hartman, N.; Heimann, P.; Lafever, R.; Li, D.; Padmore, H.; Rimmer, R.; Robinson, K.E.; Schoenlein, R.; Tanabe, J.; Wang, S.; Zholents, A.; Kairan, D.

    2001-06-16

    We describe a proposed femtosecond synchrotron radiation x-ray source based on a flat-beam RF gun and a recirculating superconducting linac that provides beam to an array of undulators and bend magnets. X-ray pulse durations of <100 fs at a 10 kHz repetition rate are obtained by a combination of electron pulse compression, transverse temporal correlation of the electrons, and x-ray pulse compression.

  6. Multiwavelength Study of Chandra X-Ray Sources in the Antennae

    CERN Document Server

    Clark, D M; Brandl, B R; Wilson, J C; Carson, J C; Henderson, C P; Hayward, T L; Barry, D J; Ptak, A F; Colbert, E J M

    2010-01-01

    We use WIRC, IR images of the Antennae (NGC 4038/4039) together with the extensive catalogue of 120 X-ray point sources (Zezas et al. 2006) to search for counterpart candidates. Using our proven frame-tie technique, we find 38 X-ray sources with IR counterparts, almost doubling the number of IR counterparts to X-ray sources first identified in Clark et al. (2007). In our photometric analysis, we consider the 35 IR counterparts that are confirmed star clusters. We show that the clusters with X-ray sources tend to be brighter, K_s ~16 mag, with (J-K_s) = 1.1 mag. We then use archival HST images of the Antennae to search for optical counterparts to the X-ray point sources. We employ our previous IR-to-X-ray frame-tie as an intermediary to establish a precise optical-to-X-ray frame-tie with <0.6 arcsec rms positional uncertainty. Due to the high optical source density near the X-ray sources, we determine that we cannot reliably identify counterparts. Comparing the HST positions to the 35 identified IR star clu...

  7. 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.

  8. Transmission type flat-panel X-ray source using ZnO nanowire field emitters

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Daokun; Song, Xiaomeng; Zhang, Zhipeng; Chen, Jun, E-mail: stscjun@mail.sysu.edu.cn [State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Province Key Laboratory of Display Material and Technology, Sun Yat-sen University, Guangzhou 510275 (China); School of Physics and Engineering, Sun Yat-sen University, Guangzhou 510275 (China); Li, Ziping [The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510275 (China); She, Juncong; Deng, Shaozhi; Xu, Ningsheng [State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Province Key Laboratory of Display Material and Technology, Sun Yat-sen University, Guangzhou 510275 (China); School of Microelectronics, Sun Yat-sen University, Guangzhou 510275 (China)

    2015-12-14

    A transmission type flat-panel X-ray source in diode structure was fabricated. Large-scale patterned ZnO nanowires grown on a glass substrate by thermal oxidation were utilized as field emitters, and tungsten thin film coated on silica glass was used as the transmission anode. Uniform distribution of X-ray generation was achieved, which benefited from the uniform electron emission from ZnO nanowires. Self-ballasting effect induced by the intrinsic resistance of ZnO nanowire and decreasing of screening effect caused by patterned emitters account for the uniform emission. Characteristic X-ray peaks of W-L lines and bremsstrahlung X-rays have been observed under anode voltages at a range of 18–20 kV, the latter of which were the dominant X-ray signals. High-resolution X-ray images with spatial resolution less than 25 μm were obtained by the flat-panel X-ray source. The high resolution was attributed to the small divergence angle of the emitted X-rays from the transmission X-ray source.

  9. Stereoscopic observations of a solar flare hard X-ray source in the high corona

    Science.gov (United States)

    Kane, S. R.; Mctiernan, J.; Loran, J.; Fenimore, E. E.; Klebesadel, R. W.; Laros, J. G.

    1992-01-01

    The vertical structure of the impulsive and gradual hard X-ray sources in high coronae and the characteristics of the impulsive soft X-ray emission are investigated on the basis of PVE, ICE, and GOES observations of the energetic flare on February 16, 1984. The average photon spectra observed by these instruments during the impulsive and gradual hard X-ray bursts are summarized. A comparison of these unocculted and partially occulted spectra shows that the sources of the impulsive hard X-ray (greater than about 25 keV) and impulsive soft X-ray (2-5 keV) emissions in this flare extended to coronal altitudes greater than about 200,000 km above the photosphere. At about 100 keV, the ratio of the coronal source brightness to the total source brightness was 0.001 during the impulsive phase and less than about 0.01 during the gradual hard X-ray burst. The sources of the gradual hard X-ray burst and gradual soft X-ray burst were almost completely occulted, indicating that these sources were located at heights less than 200,000 km above the photosphere.

  10. THREE NEW GALACTIC CENTER X-RAY SOURCES IDENTIFIED WITH NEAR-INFRARED SPECTROSCOPY

    Energy Technology Data Exchange (ETDEWEB)

    DeWitt, Curtis [Department of Physics, University of California, Davis, CA 95616 (United States); Bandyopadhyay, Reba M.; Eikenberry, Stephen S.; Sarajedini, Ata [Department of Astronomy, University of Florida, 211 Bryant Space Center, P.O. Box 112055, Gainesville, FL 32611 (United States); Sellgren, Kris [Department of Astronomy, The Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Blum, Robert; Olsen, Knut [National Optical Astronomy Observatories, Tucson, AZ 85719 (United States); Bauer, Franz E., E-mail: curtis.n.dewitt@nasa.gov [Departamento de Astronomía y Astrofísica, Pontificia Universidad Católica de Chile, Casilla 306, Santiago 22 (Chile)

    2013-11-01

    We have conducted a near-infrared spectroscopic survey of 47 candidate counterparts to X-ray sources discovered by the Chandra X-Ray Observatory near the Galactic center (GC). Though a significant number of these astrometric matches are likely to be spurious, we sought out spectral characteristics of active stars and interacting binaries, such as hot, massive spectral types or emission lines, in order to corroborate the X-ray activity and certify the authenticity of the match. We present three new spectroscopic identifications, including a Be high-mass X-ray binary (HMXB) or a γ Cassiopeiae (Cas) system, a symbiotic X-ray binary, and an O-type star of unknown luminosity class. The Be HMXB/γ Cas system and the symbiotic X-ray binary are the first of their classes to be spectroscopically identified in the GC region.

  11. DEVELOPMENT OF NEW MID-INFRARED ULTRAFAST LASER SOURCES FOR COMPACT COHERENT X-RAY SOURCES

    Energy Technology Data Exchange (ETDEWEB)

    Sterling Backus

    2012-05-14

    In this project, we proposed to develop laser based mid-infrared lasers as a potentially robust and reliable source of ultrafast pulses in the mid-infrared region of the spectrum, and to apply this light source to generating bright, coherent, femtosecond-to-attosecond x-ray beams.

  12. Droplet-based, high-brightness extreme ultraviolet laser plasma source for metrology

    Science.gov (United States)

    Vinokhodov, A. Yu.; Krivokorytov, M. S.; Sidelnikov, Yu. V.; Krivtsun, V. M.; Medvedev, V. V.; Koshelev, K. N.

    2016-10-01

    We report on the development of a high brightness source of extreme ultraviolet radiation (EUV) with a working wavelength of 13.5 nm. The source is based on a laser-produced plasma driven by pulsed radiation of a Nd:YAG laser system. Liquid droplets of Sn-In eutectic alloy were used as the source fuel. The droplets were created by a droplet generator operating in the jet break-up regime. The EUV emission properties of the plasma, including the emission spectrum, time profile, and conversion efficiency of laser radiation into useful 13.5 nm photons, have been characterized. Using the shadowgraphy technique, we demonstrated the production of corpuscular debris by the plasma source and the influence of the plasma on the neighboring droplet targets. The high-frequency laser operation was simulated by usage of the dual pulse regime. Based on the experimental results, we discuss the physical phenomena that could affect the source operation at high repetition rates. Finally, we estimate that an average source brightness of 1.2 kW/mm2 sr is feasible at a high repetition rate.

  13. Development of a multilayer mirror for high-intensity monochromatic x-ray using lab-based x-ray source.

    Science.gov (United States)

    Nguyen, Thanh-hai; Song, Seonggeun; Jung, Jin-Ho; Jeon, Insu

    2012-09-15

    A parabolic, multilayer x-ray mirror, which can be used with a general lab-based x-ray source, was designed and fabricated. A glass substrate for the mirror was fabricated. Its surface was determined by following the rotation of a parabolic curve and was polished precisely. On the substrate surface, six W/Al bilayers were deposited to form the multilayer mirror. The effects of the mirror on x-ray images were investigated based on the calculated modulation transfer function (MTF) and image intensity values. Higher MTF and intensity values of an x-ray image were obtained using the mirror.

  14. Time-resolved Rocking Curve Measurement Method using Laboratory X-ray Source

    OpenAIRE

    林, 雄二郎; 佐藤, 真伸; 古賀, 三井; 佃, 昇; 蔵元, 英一

    2005-01-01

    Fast x-ray detectors and fast signal processing devices have enabled to measure time dependence of x-ray diffraction intensity. Using a fast x-ray detection system, we have developed a time-resolved measurement method of rocking curves with a laboratory x-ray source. The method has been demonstrated for time-resolved rocking curves from an ultrasound-vibrated silicon crystal in MHz range. The measured rocking curves have been consistent with simulated curves based on the dynamical diffraction...

  15. Source effects in analyzer-based X-ray phase contrast imaging with conventional sources

    Energy Technology Data Exchange (ETDEWEB)

    Hoennicke, M. G. [Universidade Federal da Integracao Latino-Americana, 85867-970 Foz do Iguacu, PR (Brazil); Manica, J. [Universidade Estadual do Oeste do Parana, 85867-970 Foz do Iguacu, PR (Brazil); Mazzaro, I.; Cusatis, C. [LORXI, Departamento de Fisica, Universidade Federal do Parana, Caixa Postal 19091, 81531-990 Curitiba, PR (Brazil); Huang, X.-R. [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

    2012-11-15

    Several recent papers have shown the implementation of analyzer based X-ray phase contrast imaging (ABI) with conventional X-ray sources. The high flux is always a requirement to make the technique useful for bio-medical applications. Here, we present and discuss three important parameters, which need to be taken into account, when searching for the high flux ABI: anisotropic magnification, double image, and source size spread due to intrinsic dispersive diffraction by asymmetrically cut crystals. These parameters, if not well optimized, may cause important features in the acquired images which can mislead the interpretation. A few ways to minimize these effects are implemented and discussed, including some experimental results.

  16. S-band linac-based X-ray source with {pi}/2-mode electron linac

    Energy Technology Data Exchange (ETDEWEB)

    Deshpande, Abhay, E-mail: abhay@post.kek.jp [Department of Accelerator Science, School of High Energy Accelerator Science, Graduate University for Advanced Studies, Shonan International Village, Hayama, Miura, Kanagawa 240-0193 (Japan); Society for Applied Microwave Electronic Engineering and Research (SAMEER), R and D Laboratory of the Government of India, IIT Campus, Powai, Mumbai 400 076 (India); Araki, Sakae [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Dixit, Tanuja [Society for Applied Microwave Electronic Engineering and Research (SAMEER), R and D Laboratory of the Government of India, IIT Campus, Powai, Mumbai 400 076 (India); Fukuda, Masafumi [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Krishnan, R; Pethe, Sanjay [Society for Applied Microwave Electronic Engineering and Research (SAMEER), R and D Laboratory of the Government of India, IIT Campus, Powai, Mumbai 400 076 (India); Sakaue, Kazuyuki [Waseda University, Shinjuku-ku, Tokyo 169-8555 (Japan); Terunuma, Nobuhiro; Urakawa, Junji [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Washio, Masakazu [Waseda University, Shinjuku-ku, Tokyo 169-8555 (Japan)

    2011-05-01

    The activities with the compact X-ray source are attracting more attention, particularly for the applications of the source in medical fields. We propose the fabrication of a compact X-ray source using the SAMEER electron linear accelerator and the KEK laser undulator X-ray source (LUCX) technologies. The linac developed at SAMEER is a standing wave side-coupled S-band linac operating in the {pi}/2 mode. In the proposed system, a photocathode RF gun will inject bunches of electrons in the linac to accelerate and achieve a high-energy, low-emittance beam. This beam will then interact with the laser in the laser cavity to produce X-rays of a type well suited for various applications. The side-coupled structure will make the system more compact, and the {pi}/2 mode of operation will enable a high repetition rate operation, which will help to increase the X-ray yield.

  17. On the black hole masses in ultra-luminous X-ray sources

    Science.gov (United States)

    Zhou, Xin-Lin

    2015-05-01

    Ultra-luminous X-ray sources (ULXs) are off-nuclear X-ray sources in nearby galaxies with X-ray luminosities ⩾ 1039 erg s-1. The measurement of the black hole (BH) masses of ULXs is a long-standing problem. Here we estimate BH masses in a sample of ULXs with XMM-Newton observations using two different mass indicators, the X-ray photon index and X-ray variability amplitude based on the correlations established for active galactic nuclei (AGNs). The BH masses estimated from the two methods are compared and discussed. We find that some extreme high-luminosity (LX > 5 ×1040 erg s-1) ULXs contain the BH of 104-105 M⊙ . The results from X-ray variability amplitude are in conflict with those from X-ray photon indices for ULXs with lower luminosities. This suggests that these ULXs generally accrete at rates different from those of X-ray luminous AGNs, or they have different power spectral densities of X-ray variability. We conclude that most of ULXs accrete at super-Eddington rate, thus harbor stellar-mass BH.

  18. CHANDRA ACIS Survey of X-Ray Point Sources: The Source Catalog

    Science.gov (United States)

    Wang, Song; Liu, Jifeng; Qiu, Yanli; Bai, Yu; Yang, Huiqin; Guo, Jincheng; Zhang, Peng

    2016-06-01

    The Chandra archival data is a valuable resource for various studies on different X-ray astronomy topics. In this paper, we utilize this wealth of information and present a uniformly processed data set, which can be used to address a wide range of scientific questions. The data analysis procedures are applied to 10,029 Advanced CCD Imaging Spectrometer observations, which produces 363,530 source detections belonging to 217,828 distinct X-ray sources. This number is twice the size of the Chandra Source Catalog (Version 1.1). The catalogs in this paper provide abundant estimates of the detected X-ray source properties, including source positions, counts, colors, fluxes, luminosities, variability statistics, etc. Cross-correlation of these objects with galaxies shows that 17,828 sources are located within the D 25 isophotes of 1110 galaxies, and 7504 sources are located between the D 25 and 2D 25 isophotes of 910 galaxies. Contamination analysis with the log N-log S relation indicates that 51.3% of objects within 2D 25 isophotes are truly relevant to galaxies, and the “net” source fraction increases to 58.9%, 67.3%, and 69.1% for sources with luminosities above 1037, 1038, and 1039 erg s-1, respectively. Among the possible scientific uses of this catalog, we discuss the possibility of studying intra-observation variability, inter-observation variability, and supersoft sources (SSSs). About 17,092 detected sources above 10 counts are classified as variable in individual observation with the Kolmogorov-Smirnov (K-S) criterion (P K-S < 0.01). There are 99,647 sources observed more than once and 11,843 sources observed 10 times or more, offering us a wealth of data with which to explore the long-term variability. There are 1638 individual objects (˜2350 detections) classified as SSSs. As a quite interesting subclass, detailed studies on X-ray spectra and optical spectroscopic follow-up are needed to categorize these SSSs and pinpoint their properties. In addition

  19. The X-ray spectral evolution of the ultraluminous X-ray source Holmberg IX X-1

    CERN Document Server

    Luangtip, W; Done, C

    2016-01-01

    We present a new analysis of X-ray spectra of the archetypal ultraluminous X-ray source (ULX) Holmberg IX X-1 obtained by the Swift, XMM-Newton and NuSTAR observatories. This ULX is a persistent source, with a typical luminosity of ~10^40 erg s^-1, that varied by a factor of 4 - 5 over eight years. We find that its spectra tend to evolve from relatively flat or two-component spectra in the medium energy band (1-6 keV), at lower luminosities, to a spectrum that is distinctly curved and disc-like at the highest luminosities, with the peak energy in the curved spectrum tending to decrease with increased luminosity. We argue that the spectral evolution of the ULX can be explained by super-Eddington accretion models, where in this case we view the ULX down the evacuated funnel along its rotation axis, bounded by its massive radiatively driven wind. The spectral changes then originate in enhanced geometric beaming as the accretion rate increases and wind funnel narrows, causing the scattered flux from the central r...

  20. Studies of Supersoft X-ray Sources (SSS) and Quasisoft X-ray Sources (QSS) in the Milky Way and Magellanic Clouds

    Science.gov (United States)

    Pun, Chun-Shing J.; Li, K.; Kong, A. K. H.; DiStefano, R.

    2010-03-01

    Quasisoft X-ray sources (QSSs) are luminous (L > 1036 erg s-1, kT between 120eV and 350eV) X-ray sources emitting few or no photons at energy above 2 keV yet clearly emitting at above 1.1 keV. While their spectra are harder than luminous supersoft X-ray sources (SSSs), which have characteristic temperatures of tens of eV, QSSs are significantly softer than most canonical X-ray sources. They have been identified in elliptical galaxies, spiral galaxies (in both spiral arms and halos), and globular clusters. We report here on the progress of a comprehensive and systematic search of SSSs and QSSs in the Milky Way and in the Magellanic Clouds using archival X-ray data. Our focus is to conduct an optimized search to identify all candidates in order to differentiate between the different natures of SSSs and QSSs. The candidates collected would be checked for counterparts in other wavelengths, which could possibly help us to determine the fundamental nature of these sources, including the properties, if present, of the accretors and the accretion disks. This work is supported by a Hong Kong SAR Research Grants Council General Research Fund and by a NASA ADP grant.

  1. Near-infrared counterparts of Chandra X-ray sources toward the Galactic Center

    CERN Document Server

    DeWitt, Curtis; Eikenberry, Stephen S; Blum, Robert; Olsen, Knut; Sellgren, Kris; Sarajedini, Ata

    2010-01-01

    The Chandra X-ray Observatory has now discovered nearly 10,000 X-ray point sources in the 2 x 0.8 degree region around the Galactic Center (Muno 2009). The sources are likely to be a population of accreting binaries in the Galactic Center, but little else is known of their nature. We obtained JHKs imaging of the 17'x 17' region around Sgr A*, an area containing 4339 of these X-ray sources, with the ISPI camera on the CTIO 4-m telescope. We cross-correlate the Chandra and ISPI catalogs to find potential IR counterparts to the X-ray sources. The extreme IR source crowding in the field means that it is not possible to establish the authenticity of the matches with astrometry and photometry alone. We find 2137 IR/X-ray astrometrically matched sources: statistically we estimate that our catalog contains 289 +/- 13 true matches to soft X-ray sources and 154 +/- 39 matches to hard X-ray sources. However, the fraction of true counterparts to candidate counterparts for hard sources is just 11 %, compared to 60 % for s...

  2. Broadband X-ray spectra of the ultraluminous x-ray source Holmberg IX X-1 observed with NuSTAR, XMM-Newton, and Suzaku

    DEFF Research Database (Denmark)

    Walton, D. J.; Harrison, F. A.; Grefenstette, B. W.;

    2014-01-01

    We present results from the coordinated broadband X-ray observations of the extreme ultraluminous X-ray source Holmberg IX X-1 performed by NuSTAR, XMM-Newton, and Suzaku in late 2012. These observations provide the first high-quality spectra of Holmberg IX X-1 above 10 keV to date, extending the X...

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

    DEFF Research Database (Denmark)

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

    2015-01-01

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

  4. Development of low-energy x-ray fluorescence micro-distribution analysis using a laser plasma x-ray source and multilayer optics?

    NARCIS (Netherlands)

    Stuik, R.; Shmaenok, L. A.; Fledderus, H.; Andreev, S. S.; Shamov, E. A.; Zuev, S. Y.; Salashchenko, N. N.; F. Bijkerk,

    1999-01-01

    A new technique is presented for low-energy X-ray fluorescence micro-distribution analysis of low-Z elements at micrometer spatial resolutions. The technique is based on the use of a laser plasma X-ray source and spherically curved multilayer optics. A large collimator is used to focus the light fro

  5. Monitoring the activity variations of galactic X-ray sources with WATCH on EURECA

    DEFF Research Database (Denmark)

    Brandt, Søren; Lund, N.

    1995-01-01

    sources the observation periods extended over more than 100 days. A number of X-ray transients with durations between one and five days were discovered, and, additionally two long duration X-ray transients (GRS 1915+10 and GRO J0422+32) were active and could be monitored. Towards the end of the mission...

  6. Shielded radiography with a laser-driven MeV-energy X-ray source

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Shouyuan; Golovin, Grigory [Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, NE 68588 (United States); Miller, Cameron [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI 48109 (United States); Haden, Daniel; Banerjee, Sudeep; Zhang, Ping; Liu, Cheng; Zhang, Jun; Zhao, Baozhen [Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, NE 68588 (United States); Clarke, Shaun; Pozzi, Sara [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI 48109 (United States); Umstadter, Donald, E-mail: donald.umstadter@unl.edu [Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, NE 68588 (United States)

    2016-01-01

    We report the results of experimental and numerical-simulation studies of shielded radiography using narrowband MeV-energy X-rays from a compact all-laser-driven inverse-Compton-scattering X-ray light source. This recently developed X-ray light source is based on a laser-wakefield accelerator with ultra-high-field gradient (GeV/cm). We demonstrate experimentally high-quality radiographic imaging (image contrast of 0.4 and signal-to-noise ratio of 2:1) of a target composed of 8-mm thick depleted uranium shielded by 80-mm thick steel, using a 6-MeV X-ray beam with a spread of 45% (FWHM) and 10{sup 7} photons in a single shot. The corresponding dose of the X-ray pulse measured in front of the target is ∼100 nGy/pulse. Simulations performed using the Monte-Carlo code MCNPX accurately reproduce the experimental results. These simulations also demonstrate that the narrow bandwidth of the Compton X-ray source operating at 6 and 9 MeV leads to a reduction of deposited dose as compared to broadband bremsstrahlung sources with the same end-point energy. The X-ray beam’s inherently low-divergence angle (∼mrad) is advantageous and effective for interrogation at standoff distance. These results demonstrate significant benefits of all-laser driven Compton X-rays for shielded radiography.

  7. Pile-up corrections in laser-driven pulsed x-ray sources

    CERN Document Server

    Hernández, Guillermo

    2016-01-01

    A formalism for treating the pile-up produced in laser-driven pulsed x-ray sources has been developed. It allows the direct use of x-ray spectroscopy without artificially decreasing the number of counts in the detector. The influence of the pile-up on the overestimation of temperature parameters is shown up.

  8. The X-ray source content of the XGPS Galactic Plane Survey

    CERN Document Server

    Motch, C; Cropper, M S; Carrera, F; Guillout, P; Pineau, F X; Pakull, M W; Rosen, S; Schwope, A; Tedds, J; Webb, N; Negueruela, I; Watson, M G

    2009-01-01

    We report the results of an optical campaign carried out by the XMM-Newton Survey Science Centre with the specific goal of identifying the brightest X-ray sources in the XMM-Newton Galactic Plane Survey of Hands et al. (2004). In addition to photometric and spectroscopic observations obtained at the ESO-VLT and ESO-3.6m, we used cross-correlations with the 2XMMi, USNO-B1.0, 2MASS and GLIMPSE catalogues to progress the identification process. Active coronae account for 16 of the 30 identified X-ray sources. Many of the identified hard X-ray sources are associated with massive stars emitting at intermediate X-ray luminosities of 10^32-34 erg/s. Among these are a very absorbed likely hyper-luminous star with X-ray/optical spectra and luminosities comparable with those of eta Carina, a new X-ray selected WN8 Wolf-Rayet star, a new Be/X-ray star belonging to the growing class of Gamma-Cas analogs and a possible supergiant X-ray binary of the kind discovered recently by INTEGRAL. One of the sources, XGPS-25 has a c...

  9. Laser-Plasma Sources for Soft-X-Ray Projection Lithography

    NARCIS (Netherlands)

    F. Bijkerk,; Shmaenok, L.; Vanhonk, A.; Bastiaensen, R.; Platonov, Y. Y.; Shevelko, A. P.; Mitrofanov, A. V.; Voss, F.; Desor, R.; Frowein, H.; Nikolaus, B.

    1994-01-01

    Results are reported concerning high-repetition-rate excimer lasers with average powers up to 415 W and their usage for generating laser-plasma soft X-ray sources. A conversion efficiency of laser light into monochromatized soft X-ray radiation of 0.7% at 13.5 nm (2% bandwidth) was achieved using an

  10. Laser-Plasma Sources for Soft-X-Ray Projection Lithography

    NARCIS (Netherlands)

    F. Bijkerk,; Shmaenok, L.; Vanhonk, A.; Bastiaensen, R.; Platonov, Y. Y.; Shevelko, A. P.; Mitrofanov, A. V.; Voss, F.; Desor, R.; Frowein, H.; Nikolaus, B.

    1994-01-01

    Results are reported concerning high-repetition-rate excimer lasers with average powers up to 415 W and their usage for generating laser-plasma soft X-ray sources. A conversion efficiency of laser light into monochromatized soft X-ray radiation of 0.7% at 13.5 nm (2% bandwidth) was achieved using an

  11. Spot size diagnostics for flash radiographic X-ray sources at LAPA

    Institute of Scientific and Technical Information of China (English)

    LI Cheng-Gang; LI Qin; SHI Jin-Shui; DENG Jian-Jun

    2009-01-01

    Spot size is one of the parameters to characterize the performance of a radiographic X-ray source.It determines the degree of blurring due to magnification directly.In recent years,a variety of measurement methods have been used to diagnose X-ray spot size at Laboratory of Accelerator Physics and Application (LAPA).Computer simulations and experiments showed that using a rolled-edge to measure the spot size are more accurate,and the intensity distribution of X-ray source was obtained by a device with a square aperture.Experimental and simulation results on a flash X-ray source at our laboratory are presented and discussed in this paper.In addition,a new method for time resolved diagnostics of X-ray spot size is introduced too.

  12. 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)

  13. A search for hyperluminous X-ray sources in the XMM-Newton source catalog

    CERN Document Server

    Zolotukhin, Ivan; Godet, Olivier; Bachetti, Matteo; Barret, Didier

    2015-01-01

    We present a new method to identify luminous off-nuclear X-ray sources in the outskirts of galaxies from large public redshift surveys, distinguishing them from foreground and background interlopers. Using the 3XMM-DR5 catalog of X-ray sources and the SDSS DR12 spectroscopic sample of galaxies, with the help of this off-nuclear cross-matching technique, we selected 98 sources with inferred X-ray luminosities in the range $10^{41} < L_{\\rm X} < 10^{44}\\,{\\rm erg\\,s}^{-1}$, compatible with hyperluminous X-ray objects (HLX). To validate the method, we verify that it allowed us to recover known HLX candidates such as ESO 243$-$49 HLX$-$1 and M82 X$-$1. From a statistical study, we conservatively estimate that up to $71 \\pm 11$ of these sources may be fore- or background sources, statistically leaving at least 16 that are likely to be HLXs, thus providing support for the existence of the HLX population. We identify two good HLX candidates and using other publicly available datasets, in particular the VLA FIR...

  14. X-ray sources and their optical counterparts in the globular cluster M 22

    CERN Document Server

    Webb, N A; Gendre, B; Barret, D; Lasota, J P; Rizzi, L

    2004-01-01

    Using XMM-Newton EPIC imaging data, we have detected 50 low-luminosity X-ray sources in the field of view of M 22, where 5 +/- 3 of these sources are likely to be related to the cluster. Using differential optical photometry, we have identified probable counterparts to those sources belonging to the cluster. Using X-ray spectroscopic and timing studies, supported by the optical colours, we propose that the most central X-ray sources in the cluster are cataclysmic variables, millisecond pulsars, active binaries and a blue straggler. We also identify a cluster of galaxies behind this globular cluster.

  15. X-ray Sources in the Hubble Deep Field Detected by Chandra

    CERN Document Server

    Hornschemeier, A E; Garmire, G P; Schneider, D P; Broos, P S; Townsley, L K; Bautz, M W; Burrows, D N; Chartas, G; Feigelson, E D; Griffiths, R; Lumb, D H; Nousek, J A; Sargent, W L W

    2000-01-01

    We present first results from an X-ray study of the Hubble Deep Field North (HDF-N) and its environs obtained using 166 ks of data collected by the Advanced CCD Imaging Spectrometer (ACIS) on board the Chandra X-ray Observatory. This is the deepest X-ray observation ever reported, and in the HDF-N itself we detect six X-ray sources down to a 0.5--8 keV flux limit of 4E-16 erg cm^-2 s^-1. Comparing these sources with objects seen in multiwavelength HDF-N studies shows positional coincidences with the extremely red object NICMOS J123651.74 +621221.4, an active galactic nucleus (AGN), three elliptical galaxies, and one nearby spiral galaxy. The X-ray emission from the ellipticals is consistent with that expected from a hot interstellar medium, and the spiral galaxy emission may arise from a `super-Eddington' X-ray binary or ultraluminous supernova remnant. Four of the X-ray sources have been detected at radio wavelengths. We also place X-ray upper limits on AGN candidates found in the HDF-N, and we present the t...

  16. THE CHANDRA LOCAL VOLUME SURVEY: THE X-RAY POINT-SOURCE CATALOG OF NGC 300

    Energy Technology Data Exchange (ETDEWEB)

    Binder, B.; Williams, B. F.; Dalcanton, J. J.; Anderson, S. F.; Weisz, D. R. [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Eracleous, M. [Department of Astronomy and Astrophysics, Pennsylvania State University, 525 Davey Laboratory, University Park, PA 16802 (United States); Gaetz, T. J.; Plucinsky, P. P. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street Cambridge, MA 02138 (United States); Skillman, E. D. [Astronomy Department, University of Minnesota, 116 Church St. SE, Minneapolis, MN 55455 (United States); Kong, A. K. H. [Institute of Astronomy and Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China)

    2012-10-10

    We present the source catalog of a new Chandra ACIS-I observation of NGC 300 obtained as part of the Chandra Local Volume Survey. Our 63 ks exposure covers {approx}88% of the D{sub 25} isophote (R Almost-Equal-To 6.3 kpc) and yields a catalog of 95 X-ray point sources detected at high significance to a limiting unabsorbed 0.35-8 keV luminosity of {approx}10{sup 36} erg s{sup -1}. Sources were cross-correlated with a previous XMM-Newton catalog, and we find 75 'X-ray transient candidate' sources that were detected by one observatory, but not the other. We derive an X-ray scale length of 1.7 {+-} 0.2 kpc and a recent star formation rate of 0.12 M{sub Sun} yr{sup -1} in excellent agreement with optical observations. Deep, multi-color imaging from the Hubble Space Telescope, covering {approx}32% of our Chandra field, was used to search for optical counterparts to the X-ray sources, and we have developed a new source classification scheme to determine which sources are likely X-ray binaries, supernova remnants, and background active galactic nucleus candidates. Finally, we present the X-ray luminosity functions (XLFs) at different X-ray energies, and we find the total NGC 300 X-ray point-source population to be consistent with other late-type galaxies hosting young stellar populations ({approx}< 50 Myr). We find that XLF of sources associated with older stellar populations has a steeper slope than the XLF of X-ray sources coinciding with young stellar populations, consistent with theoretical predictions.

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

    CERN Document Server

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

    2015-01-01

    The nature of the low- to intermediate-luminosity (Lx$\\,\\sim 10^{32-34}$ erg s$^{-1}$) source population revealed in hard band (2-10 keV) X-ray surveys of the Galactic Plane is poorly understood. To overcome such problem we cross-correlated the XMM-Newton 3XMM-DR4 survey with the infrared 2MASS and GLIMPSE catalogues. We identified reliable X-ray-infrared associations for 690 sources. We selected 173 sources having hard X-ray spectra, typical of hard X-ray high-mass stars (kT$\\,>\\,5\\,$keV), and 517 sources having soft X-ray spectra, typical of active coronae. About $18\\,\\%$ of the soft sources are classified in the literature: $\\sim\\,91\\%$ as stars, with a minor fraction of WR stars. Roughly $15\\,\\%$ of the hard sources are classified in the literature: $\\sim\\,68\\%$ as high-mass X-ray stars single or in binary systems (WR, Be and HMXBs), with a small fraction of G and B stars. We carried out infrared spectroscopic pilot observations at the William Herschel Telescope for five hard X-ray sources. Three of them ...

  18. Quantum emitters coupled to circular nanoantennas for high-brightness quantum light sources

    Science.gov (United States)

    Abudayyeh, Hamza A.; Rapaport, Ronen

    2017-09-01

    Engineering the directionality and emission rate of quantum light sources is essential in the development of modern quantum applications. In this work we use numerical calculations to optimise the brightness of a broadband quantum emitter positioned in a hybrid metal-dielectric circular periodic nanoantenna. The optimised structure features a photon collection efficiency of 74 % (82 % ) and a photon flux enhancement of over 10 (6) into a numerical aperture of 0.22 (0.50), respectively, corresponding to a direct coupling into two types of multi-mode fibres. To enhance the emission rate, we present a new circular nanoantenna design where a quantum emitter is attached to a silver nanocone at the centre of the antenna. After optimisation, we find a collection efficiency of 61 % (78 % ) into a numerical aperture of 0.22 (0.50), giving a brightness enhancement of 1000 (600) for an unpolarised emitter. The enhancements in both structures are broadband due to the low-quality factor of the device and are therefore ideal for room-temperature sources. This type of a scalable design can be utilised towards on-chip, high-brightness quantum light sources operating at room temperature.

  19. THE CHANDRA LOCAL VOLUME SURVEY: THE X-RAY POINT-SOURCE POPULATION OF NGC 404

    Energy Technology Data Exchange (ETDEWEB)

    Binder, B.; Williams, B. F.; Weisz, D. R. [University of Washington, Department of Astronomy, Box 351580, Seattle, WA 98195 (United States); Eracleous, M. [Department of Astronomy and Astrophysics and Center for Gravitational Wave Physics, The Pennsylvania State University, 525 Davey Lab, University Park, PA 16802 (United States); Gaetz, T. J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street Cambridge, MA 02138 (United States); Kong, A. K. H. [Institute of Astronomy and Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Skillman, E. D. [University of Minnesota, Astronomy Department, 116 Church St. SE, Minneapolis, MN 55455 (United States)

    2013-02-15

    We present a comprehensive X-ray point-source catalog of NGC 404 obtained as part of the Chandra Local Volume Survey. A new 97 ks Chandra ACIS-S observation of NGC 404 was combined with archival observations for a total exposure of {approx}123 ks. Our survey yields 74 highly significant X-ray point sources and is sensitive to a limiting unabsorbed luminosity of {approx}6 Multiplication-Sign 10{sup 35} erg s{sup -1} in the 0.35-8 keV band. To constrain the nature of each X-ray source, cross-correlations with multi-wavelength data were generated. We searched overlapping Hubble Space Telescope observations for optical counterparts to our X-ray detections, but find only two X-ray sources with candidate optical counterparts. We find 21 likely low-mass X-ray binaries (LMXBs), although this number is a lower limit due to the difficulties in separating LMXBs from background active galactic nuclei. The X-ray luminosity functions (XLFs) in both the soft and hard energy bands are presented. The XLFs in the soft band (0.5-2 keV) and the hard band (2-8 keV) have a limiting luminosity at the 90% completeness limit of 10{sup 35} erg s{sup -1} and 10{sup 36} erg s{sup -1}, respectively, significantly lower than previous X-ray studies of NGC 404. We find the XLFs to be consistent with those of other X-ray populations dominated by LMXBs. However, the number of luminous (>10{sup 37} erg s{sup -1}) X-ray sources per unit stellar mass in NGC 404 is lower than is observed for other galaxies. The relative lack of luminous XRBs may be due to a population of LMXBs with main-sequence companions formed during an epoch of elevated star formation {approx}0.5 Gyr ago.

  20. X-ray source development for EXAFS measurements on the National Ignition Facility

    Science.gov (United States)

    Coppari, F.; Thorn, D. B.; Kemp, G. E.; Craxton, R. S.; Garcia, E. M.; Ping, Y.; Eggert, J. H.; Schneider, M. B.

    2017-08-01

    Extended X-ray absorption Fine Structure (EXAFS) measurements require a bright, spectrally smooth, and broad-band x-ray source. In a laser facility, such an x-ray source can be generated by a laser-driven capsule implosion. In order to optimize the x-ray emission, different capsule types and laser irradiations have been tested at the National Ignition Facility (NIF). A crystal spectrometer is used to disperse the x-rays and high efficiency image plate detectors are used to measure the absorption spectra in transmission geometry. EXAFS measurements at the K-edge of iron at ambient conditions have been obtained for the first time on the NIF laser, and the requirements for optimization have been established.

  1. X-ray Sources Generated from Gas-Filled Laser-Heated Targets

    Energy Technology Data Exchange (ETDEWEB)

    Back, C A; Grun, J; Decker, C D; Davis, J; Laming, J M; Feldman, U; Suter, L J; Landen, O L; Miller, M; Serduke, F; Wuest, C

    2000-06-06

    The X-ray sources in the 4-7 keV energy regime can be produced by laser-irradiating high-Z gas-filled targets with high-powered lasers. A series of experiments have been performed using underdense targets that are supersonically heated with {approx} 35 W of 0.35 {micro}m laser light. These targets were cylindrical Be enclosures that were filled with 1-2 atms of Xe gas. L-shell x-ray emission is emitted from the plasma and detected by Bragg crystal spectrometers and x-ray diodes. Absolute flux measurements show conversion efficiencies of {approx} 10% in the multi-kilovolt x-ray emission. These sources can be used as bright x-ray backlighters or for material testing.

  2. X-ray source development for EXAFS measurements on the National Ignition Facility.

    Science.gov (United States)

    Coppari, F; Thorn, D B; Kemp, G E; Craxton, R S; Garcia, E M; Ping, Y; Eggert, J H; Schneider, M B

    2017-08-01

    Extended X-ray absorption Fine Structure (EXAFS) measurements require a bright, spectrally smooth, and broad-band x-ray source. In a laser facility, such an x-ray source can be generated by a laser-driven capsule implosion. In order to optimize the x-ray emission, different capsule types and laser irradiations have been tested at the National Ignition Facility (NIF). A crystal spectrometer is used to disperse the x-rays and high efficiency image plate detectors are used to measure the absorption spectra in transmission geometry. EXAFS measurements at the K-edge of iron at ambient conditions have been obtained for the first time on the NIF laser, and the requirements for optimization have been established.

  3. Burst-only sources: probing type I X-ray bursters at low persistent luminosities

    Energy Technology Data Exchange (ETDEWEB)

    Cornelisse, R.; Zand, J.J.M. in ' t; Kuulkers, E.; Heise, J.; Verbunt, F.; Cocchi, M.; Bazzano, A.; Natalucci, L.; Ubertini, P

    2004-06-01

    The Wide Field Cameras onboard BeppoSAX observed 9 type I X-ray bursters without detectable persistent emission around the burst. According to the standard theory of X-ray bursts these sources should be in the lowest mass-accretion regime, opening the possibility to study this regime for the first time. We compare the sources with the burst theory, and show that the evidence of a new sub-class of low mass X-ray binaries, the burst-only source, is still meagre.

  4. Anti-correlated hard X-ray time lags in Galactic black hole sources

    CERN Document Server

    Sriram, K; Pendharkar, J K; Rao, A R; Pendharkar, Jayant K.

    2007-01-01

    We investigate the accretion disk geometry in Galactic black hole sources by measuring the time delay between soft and hard X-ray emissions. Similar to the recent discoveries of anti-correlated hard X-ray time lags in Cyg X-3 and GRS 1915+105, we find that the hard X-rays are anti-correlated with soft X-rays with a significant lag in another source: XTE J1550-564. We also find the existence of pivoting in the model independent X-ray spectrum during these observations. We investigate time-resolved X-ray spectral parameters and find that the variation in these parameters is consistent with the idea of a truncated accretion disk. The QPO frequency, which is a measure of the size of truncated accretion disk, too changes indicating that the geometric size of the hard X-ray emitting region changes along with the spectral pivoting and soft X-ray flux. Similar kind of delay is also noticed in 4U 1630-47.

  5. X-ray phase-contrast tomography with a compact laser-driven synchrotron source.

    Science.gov (United States)

    Eggl, Elena; Schleede, Simone; Bech, Martin; Achterhold, Klaus; Loewen, Roderick; Ruth, Ronald D; Pfeiffer, Franz

    2015-05-05

    Between X-ray tubes and large-scale synchrotron sources, a large gap in performance exists with respect to the monochromaticity and brilliance of the X-ray beam. However, due to their size and cost, large-scale synchrotrons are not available for more routine applications in small and medium-sized academic or industrial laboratories. This gap could be closed by laser-driven compact synchrotron light sources (CLS), which use an infrared (IR) laser cavity in combination with a small electron storage ring. Hard X-rays are produced through the process of inverse Compton scattering upon the intersection of the electron bunch with the focused laser beam. The produced X-ray beam is intrinsically monochromatic and highly collimated. This makes a CLS well-suited for applications of more advanced--and more challenging--X-ray imaging approaches, such as X-ray multimodal tomography. Here we present, to our knowledge, the first results of a first successful demonstration experiment in which a monochromatic X-ray beam from a CLS was used for multimodal, i.e., phase-, dark-field, and attenuation-contrast, X-ray tomography. We show results from a fluid phantom with different liquids and a biomedical application example in the form of a multimodal CT scan of a small animal (mouse, ex vivo). The results highlight particularly that quantitative multimodal CT has become feasible with laser-driven CLS, and that the results outperform more conventional approaches.

  6. First X-ray observations of Low-Power Compact Steep Spectrum Sources

    CERN Document Server

    Kunert-Bajraszewska, M; Siemiginowska, A; Guainazzi, M

    2013-01-01

    We report first X-ray Chandra observations of a sample of seven low luminosity compact (LLC) sources. They belong to a class of young compact steep spectrum (CSS) radio sources. Four of them have been detected, the other three have upper limit estimations for X-ray flux, one CSS galaxy is associated with an X-ray cluster. We have used the new observations together with the observational data for known strong CSS and gigahertz-peaked spectrum (GPS) objects and large scale FRIs and FRIIs to study the relation between morphology, X-ray properties and excitation modes in radio-loud AGNs. We found that: (1) The low power objects fit well to the already established X-ray - radio luminosity correlation for AGNs and occupy the space among, weaker in the X-rays, FRI objects. (2) The high excitation galaxies (HEG) and low excitation galaxies (LEG) occupy distinct locus in the radio/X-ray luminosity plane, notwithstanding their evolutionary stage. This is in agreement with the postulated different origin of the X-ray em...

  7. Stable droplet generator for a high brightness laser produced plasma extreme ultraviolet source

    Science.gov (United States)

    Vinokhodov, A.; Krivokorytov, M.; Sidelnikov, Yu.; Krivtsun, V.; Medvedev, V.; Bushuev, V.; Koshelev, K.; Glushkov, D.; Ellwi, S.

    2016-10-01

    We present the results of the low-melting liquid metal droplets generation based on excited Rayleigh jet breakup. We discuss on the operation of the industrial and in-house designed and manufactured dispensing devices for the droplets generation. Droplet diameter can be varied in the range of 30-90 μm. The working frequency of the droplets, velocity, and the operating temperature were in the ranges of 20-150 kHz, 4-15 m/s, and up to 250 °C, respectively. The standard deviations for the droplet center of mass position both their diameter σ < 1 μm at the distance of 45 mm from the nozzle. Stable operation in the long-term (over 1.5 h) was demonstrated for a wide range of the droplet parameters: diameters, frequencies, and velocities. Physical factors affecting the stability of the generator operation have been identified. The technique for droplet synchronization, allowing using the droplet as a target for laser produced plasma, has been created; in particular, the generator has been successfully used in a high brightness extreme ultraviolet (EUV) light source. The operation with frequency up to 8 kHz was demonstrated as a result of the experimental simulation, which can provide an average brightness of the EUV source up to ˜1.2 kW/mm2 sr.

  8. Characterization techniques for the high-brightness particle beams of the Advanced Photon Source (APS)

    Energy Technology Data Exchange (ETDEWEB)

    Lumpkin, A.H.

    1993-08-01

    The Advanced Photon Source (APS) will be a third-generation synchrotron radiation (SR) user facility in the hard x-ray regime (10--100 keV). The design objectives for the 7-GeV storage ring include a positron beam natural emittance of 8 {times} 10{sup {minus}9} m-rad at an average current of 100 mA. Proposed methods for measuring the transverse and longitudinal profiles will be described. Additionally, a research and development effort using an rf gun as a low-emittance source of electrons for injection into the 200- to 650-MeV linac subsystem is underway. This latter system is projected to produce electron beams with a normalized, rms emittance of {approximately}2 {pi} mm-mrad at peak currents of near one hundred amps. This interesting characterization problem will also be briefly discussed. The combination of both source types within one laboratory facility will stimulate the development of diagnostic techniques in these parameter spaces.

  9. Development of a High- Brightness, Quasi- Monoenergetic Neutron Source at LLNL for Nuclear Physics Applications

    Science.gov (United States)

    Johnson, M. S.; Anderson, S. G.; Bleuel, D.; Fitsos, P. J.; Gibson, D.; Hall, J. M.; Marsh, R.; Rusnak, B.

    2016-09-01

    Lawrence Livermore National Laboratory is developing a high-brightness, quasi-monoenergetic neutron source. The intensity of the neutron source is expected to be 1011 n/s/sr with energies between 7 MeV and 10 MeV at 5% bandwidth at 0-degrees. This energy region is important for the study of neutron-induced reactions, nuclear astrophysics, and nuclear structure. For example, for neutrons between 1 and 10 MeV, the capturing states are below the GDR in many nuclei and the dominant reactions are compound and direct capture. The intensity and energy selection of the source makes it appealing for measurements of sparse targets at specific energies. We will present an array of nuclear physics measurements that will benefit from this source. The source is also of interest to generating activated targets for decay-out studies or for target production for other reaction-based measurements, e.g. fusion-evaporation reactions. Other usage examples include practical applications for imaging of very dense objects such as machine parts. For this presentation, we will discuss our method to use (d,n) production reaction on deuterium in a windowless gas target system. This approach is required because of the large power of the 7 MeV, 300 μA deuteron beams. We will discuss our facility and its capabilities. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  10. From ultraluminous X-ray sources to ultraluminous supersoft sources: NGC 55 ULX, the missing link

    Science.gov (United States)

    Pinto, C.; Alston, W.; Soria, R.; Middleton, M. J.; Walton, D. J.; Sutton, A. D.; Fabian, A. C.; Earnshaw, H.; Urquhart, R.; Kara, E.; Roberts, T. P.

    2017-07-01

    In recent work with high-resolution reflection grating spectrometers (RGS) aboard XMM-Newton, Pinto et al. have discovered that two bright and archetypal ultraluminous X-ray sources (ULXs) have strong relativistic winds in agreement with theoretical predictions of high accretion rates. It has been proposed that such winds can become optically thick enough to block and reprocess the disc X-ray photons almost entirely, making the source appear as a soft thermal emitter or ultraluminous supersoft X-ray source (ULS). To test this hypothesis, we have studied a ULX where the wind is strong enough to cause significant absorption of the hard X-ray continuum: NGC 55 ULX. The RGS spectrum of NGC 55 ULX shows a wealth of emission and absorption lines blueshifted by significant fractions of the light speed (0.01-0.20)c indicating the presence of a powerful wind. The wind has a complex dynamical structure with the ionization state increasing with the outflow velocity, which may indicate launching from different regions of the accretion disc. The comparison with other ULXs such as NGC 1313 X-1 and NGC 5408 X-1 suggests that NGC 55 ULX is being observed at higher inclination. The wind partly absorbs the source flux above 1 keV, generating a spectral drop similar to that observed in ULSs. The softening of the spectrum at lower (˜ Eddington) luminosities and the detection of a soft lag agree with the scenario of wind clumps crossing the line of sight, partly absorbing and reprocessing the hard X-rays from the innermost region.

  11. The X-ray spectral evolution of the ultraluminous X-ray source Holmberg IX X-1

    Science.gov (United States)

    Luangtip, Wasutep; Roberts, Timothy P.; Done, Chris

    2016-08-01

    We present a new analysis of X-ray spectra of the archetypal ultraluminous X-ray source (ULX) Holmberg IX X-1 obtained by the Swift, XMM-Newton and NuSTAR observatories. This ULX is a persistent source, with a typical luminosity of ˜1040 erg s-1, that varied by a factor of 4-5 over eight years. We find that its spectra tend to evolve from relatively flat or two-component spectra in the medium energy band (1-6 keV), at lower luminosities, to a spectrum that is distinctly curved and disc-like at the highest luminosities, with the peak energy in the curved spectrum tending to decrease with increased luminosity. We argue that the spectral evolution of the ULX can be explained by super-Eddington accretion models, where in this case we view the ULX down the evacuated funnel along its rotation axis, bounded by its massive radiatively driven wind. The spectral changes then originate in enhanced geometric beaming as the accretion rate increases and wind funnel narrows, causing the scattered flux from the central regions of the supercritical flow to brighten faster than the isotropic thermal emission from the wind, and so the curved hard spectral component to dominate at the highest luminosities. The wind also Compton down-scatters photons at the edge of the funnel, resulting in the peak energy of the spectrum decreasing. We also confirm that Holmberg IX X-1 displays spectral degeneracy with luminosity, and suggest that the observed differences are naturally explained by precession of the black hole rotation axis for the suggested wind geometry.

  12. Low Energy Plasma Focus as an Intense X-ray Source for Radiography

    Institute of Scientific and Technical Information of China (English)

    S. Hussain; M. Zakaullah; Shujaat Ali; A. Waheed

    2004-01-01

    Study on X-ray emission from a low energy (1.8 k J) plasma focus device powered by a 9 μF capacitor bank, charged at 20 kV and giving peak discharge current of about 175 kA by using a lead-inserted copper-tapered anode is reported. The X-ray yield in different energy windows is measured as a function of hydrogen filling pressure. The maximum yield in 4π-geometry is found to be (27.3±1.1) J and corresponding wall plug efficiency for X-ray generation is 1.52 ±0.06%. X-ray emission, presumably due to bombarding activity of electrons in current sheath at the anode tip was dominant, which is confirmed by the pinhole images. The feasibility of the device as an intense X-ray source for radiography is demonstrated.

  13. The Chandra Local Volume Survey: The X-ray Point Source Population of NGC 404

    CERN Document Server

    Binder, B; Eracleous, M; Gaetz, T J; Kong, A K H; Skillman, E D; Weisz, D R

    2012-01-01

    We present a comprehensive X-ray point source catalog of NGC 404 obtained as part of the Chandra Local Volume Survey. A new, 97 ks Chandra ACIS-S observation of NGC 404 was combined with archival observations for a total exposure of ~123 ks. Our survey yields 74 highly significant X-ray point sources and is sensitive to a limiting unabsorbed luminosity of ~6x10^35 erg s^-1 in the 0.35-8 keV band. To constrain the nature of each X-ray source, cross-correlations with multi-wavelength data were generated. We searched overlapping HST observations for optical counterparts to our X-ray detections, but find only two X-ray sources with candidate optical counterparts. We find 21 likely low mass X-ray binaries (LMXBs), although this number is a lower limit due to the difficulties in separating LMXBs from background AGN. The X-ray luminosity functions (XLFs) in both the soft and hard energy bands are presented. The XLFs in the soft band (0.5-2 keV) and the hard band (2-8 keV) have a limiting luminosity at the 90% comple...

  14. Catalytic action of β source on x-ray emission from plasma focus

    Science.gov (United States)

    Ahmad, S.; Sadiq, Mehboob; Hussain, S.; Shafiq, M.; Zakaullah, M.; Waheed, A.

    2006-01-01

    The influence of preionization around the insulator sleeve by a mesh-type β source (Ni6328) for the x-ray emission from a (2.3-3.9 kJ) plasma focus device is investigated. Quantrad Si p-i-n diodes along with suitable filters are employed as time-resolved x-ray detectors and a multipinhole camera with absorption filters is used for time-integrated analysis. X-ray emission in 4π geometry is measured as a function of argon and hydrogen gas filling pressures with and without β source at different charging voltages. It is found that the pressure range for the x-ray emission is broadened, x-ray emission is enhanced, and shot to shot reproducibility is improved with the β source. With argon, the CuKα emission is estimated to be 27.14 J with an efficiency of 0.7% for β source and 21.5 J with an efficiency of 0.55% without β source. The maximum x-ray yield in 4π geometry is found to be about 68.90 J with an efficiency of 1.8% for β source and 54.58 J with an efficiency of 1.4% without β source. With hydrogen, CuKα emission is 11.82 J with an efficiency of 0.32% for β source and 10.07 J with an efficiency of 0.27% without β source. The maximum x-ray yield in 4π geometry is found to be 30.20 J with an efficiency of 0.77% for β source and 25.58 J with an efficiency of 0.6% without β source. The x-ray emission with Pb insert at the anode tip without β source is also investigated and found to be reproducible and significantly high. The maximum x-ray yield is estimated to be 46.6 J in 4π geometry with an efficiency of 1.4% at 23 kV charging voltage. However, degradation of x-ray yield is observed when charging voltage exceeds 23 kV for Pb insert. From pinhole images it is observed that the x-ray emission due to the bombardment of electrons at the anode tip is dominant in both with and without β source.

  15. Omega Dante Soft X-Ray Power Diagnostic Component Calibration at the National Synchrotron Light Source

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, K; Weber, F; Dewald, E; Glenzer, S; Landen, O; Turner, R; Waide, P

    2004-04-15

    The Dante soft x-ray spectrometer installed on the Omega laser facility at the Laboratory for Laser Energetics, University of Rochester is a twelve-channel filter-edge defined x-ray power diagnostic. It is used to measure the absolute flux from direct drive, indirect drive (hohlraums) and other plasma sources. Calibration efforts using two beam lines, U3C (50eV-1keV) and X8A (1keV-6keV) at the National Synchrotron Light Source (NSLS) have been implemented to insure the accuracy of these measurements. We have calibrated vacuum x-ray diodes, mirrors and filters.

  16. Omega Dante soft x-ray power diagnostic component calibration at the National Synchrotron Light Source

    Science.gov (United States)

    Campbell, K. M.; Weber, F. A.; Dewald, E. L.; Glenzer, S. H.; Landen, O. L.; Turner, R. E.; Waide, P. A.

    2004-10-01

    The Dante soft x-ray spectrometer, installed on the Omega laser facility at the Laboratory for Laser Energetics, University of Rochester, is a 12-channel filter-edge defined soft x-ray power diagnostic. It is used to measure the spectrally resolved, absolute flux from direct drive, indirect drive (hohlraums) and other plasma sources. Dante component calibration efforts using two beam lines, U3C (50 eV-1 keV) and X8A (1-6 keV) at the National Synchrotron Light Source have been implemented to improve the accuracy of these measurements. We have calibrated metallic vacuum x-ray diodes, mirrors and filters.

  17. Phase-contrast imaging of a soft biological object using X-pinch as X-ray source

    Science.gov (United States)

    Liu, R.; Wang, X. X.; Zou, X. B.; Zeng, N. G.; He, L. Y.

    2008-07-01

    The X-ray emission from an X-pinch was measured with diamond photoconducting detectors and a pinhole camera, and the results show that the X-ray source of the X-pinch is extremely small in size and high in brightness. As such, the X-pinch could be considered as an X-ray point source having a high spatial coherence that is required by a simplified scheme of X-ray phase-contrast imaging. The X-pinch was used as X-ray source for the phase-contrast imaging of a weakly X-ray-absorbing mosquito and an image with high contrast was obtained.

  18. Chandra ACIS Survey of X-ray Point Sources: The Source Catalog

    CERN Document Server

    Wang, Song; Qiu, Yanli; Bai, Yu; Yang, Huiqin; Guo, Jincheng; Zhang, Peng

    2016-01-01

    The $Chandra$ archival data is a valuable resource for various studies on different topics of X-ray astronomy. In this paper, we utilize this wealth and present a uniformly processed data set, which can be used to address a wide range of scientific questions. The data analysis procedures are applied to 10,029 ACIS observations, which produces 363,530 source detections, belonging to 217,828 distinct X-ray sources. This number is twice the size of the $Chandra$ Source Catalog (Version 1.1). The catalogs in this paper provide abundant estimates of the detected X-ray source properties, including source positions, counts, colors, fluxes, luminosities, variability statistics, etc. Cross-correlation of these objects with galaxies shows 17,828 sources are located within the $D_{25}$ isophotes of 1110 galaxies, and 7504 sources are located between the $D_{25}$ and 2$D_{25}$ isophotes of 910 galaxies. Contamination analysis with the log$N$--log$S$ relation indicates that 51.3\\% of objects within 2$D_{25}$ isophotes are...

  19. X-rays beware: the deepest Chandra catalogue of point sources in M31

    Science.gov (United States)

    Vulic, N.; Gallagher, S. C.; Barmby, P.

    2016-10-01

    This study represents the most sensitive Chandra X-ray point source catalogue of M31. Using 133 publicly available Chandra ACIS-I/S observations totalling ˜1 Ms, we detected 795 X-ray sources in the bulge, north-east, and south-west fields of M31, covering an area of ≈0.6 deg2, to a limiting unabsorbed 0.5-8.0 keV luminosity of ˜1034 erg s-1. In the inner bulge, where exposure is approximately constant, X-ray fluxes represent average values because they were determined from many observations over a long period of time. Similarly, our catalogue is more complete in the bulge fields since monitoring allowed more transient sources to be detected. The catalogue was cross-correlated with a previous XMM-Newton catalogue of M31's D25 isophote consisting of 1948 X-ray sources, with only 979 within the field of view of our survey. We found 387 (49 per cent) of our Chandra sources (352 or 44 per cent unique sources) matched to within 5 arcsec of 352 XMM-Newton sources. Combining this result with matching done to previous Chandra X-ray sources we detected 259. new sources in our catalogue. We created X-ray luminosity functions (XLFs) in the soft (0.5-2.0 keV) and hard (2.0-8.0 keV) bands that are the most sensitive for any large galaxy based on our detection limits. Completeness-corrected XLFs show a break around ≈1.3 × 1037 erg s-1, consistent with previous work. As in past surveys, we find that the bulge XLFs are flatter than the disc, indicating a lack of bright high-mass X-ray binaries in the disc and an aging population of low-mass X-ray binaries in the bulge.

  20. Compensating the Electron Beam Energy Spread by the Natural Transverse Gradient of Laser Undulator in All-Optical X-ray Sources

    CERN Document Server

    Zhang, Tong; Deng, Haixiao; Wang, Dong; Dai, Zhimin; Zhao, Zhentang

    2013-01-01

    All-optical schemes provide a potential to dramatically cut off the size and cost of x-ray light sources to the university-laboratory scale, with the combination of the laser-plasma accelerator and the laser undulator. However, the large longitudinal energy spread of the electron beam from laser-plasma accelerator may hinder the way to high brightness of these all-optical light sources. In this letter, the beam energy spread effect is proposed to be significantly compensated by the natural transverse gradient of a laser undulator when properly dispersing the electron beam transversely. Theoretical analysis and numerical simulations on conventional laser-Compton scattering sources and high-gain all-optical x-ray free-electron lasers with the electron beams from laser-plasma accelerators are presented.

  1. Compensating the electron beam energy spread by the natural transverse gradient of laser undulator in all-optical x-ray light sources.

    Science.gov (United States)

    Zhang, Tong; Feng, Chao; Deng, Haixiao; Wang, Dong; Dai, Zhimin; Zhao, Zhentang

    2014-06-02

    All-optical ideas provide a potential to dramatically cut off the size and cost of x-ray light sources to the university-laboratory scale, with the combination of the laser-plasma accelerator and the laser undulator. However, the large longitudinal energy spread of the electron beam from laser-plasma accelerator may hinder the way to high brightness of these all-optical light sources. In this paper, the beam energy spread effect is proposed to be significantly compensated by the natural transverse gradient of a laser undulator when properly transverse-dispersing the electron beam. Theoretical analysis and numerical simulations on conventional laser-Compton scattering sources and high-gain all-optical x-ray free-electron lasers with the electron beams from laser-plasma accelerators are presented.

  2. Long Duration Multi-hohlraum X-ray Sources for Eagle Nebula Laboratory Experiments

    Science.gov (United States)

    Kane, Jave; Heeter, Robert; Martinez, David; Casner, Alexis; Villette, Bruno; Mancini, Roberto; Pound, Marc

    2013-10-01

    A novel foam-filled multi-hohlraum long-duration x-ray source has been demonstrated at the Omega EP laser and used to obtain L-band spectra of photoionized Ti. A larger scale version of the source will be used in the Science on NIF Eagle Nebula experiments studying dynamic evolution of distinctive pillar and cometary structures in star-forming clouds, where the long duration and directionality of photoionizing radiation from nearby stars generates new classes of flows and instabilities. At NIF, a target representing an astrophysical molecular cloud will be placed several mm from an x-ray source lasting 40-100 ns. At EP, three hohlraums were illuminated in sequence with 3.3 kJ pulses lasting 6 ns, or 4.3 kJ pulses lasting 10 ns, generating 18 or 30 ns of x-ray output at 90-100 eV color temperature. Performance of the source was validated using the μ DMX and VSG spectrometers, ASBO VISAR, and x-ray pinhole imagery. The HYDRA code suggests the EP-scale source can also be shot at NIF with at least 10 kJ per hohlraum. The multi-hohlraum source concept has potential further application to hard x-ray sources, soft x-ray backlighters, and nonlinear ablative hydrodynamics. Prepared by LLNL under Contract DE-AC52-07NA27344. J. Kane supported by DOE OFES grant HEDLP LAB 11-583.

  3. The ROSAT deep survey; 5, X-rays Sources and Optical Identifications in the Marano Field

    CERN Document Server

    Zamorani, G; Hasinger, G; Burg, R; Giacconi, R; Schmidt, M; Trümper, J E; Ciliegi, P; Gruppioni, C; Marano, B

    1999-01-01

    We present the X-ray data and the optical identifications for a deep ROSAT PSPC observation in the "Marano field". In the inner region of the ROSAT field (15' radius) we detected 50 X-ray sources with Sx >= 3.7x10^(-15) erg/cm^2/s. When corrected for the different sensitivity over the field, the estimated observed surface density at Sx >= 4x10^(-15) erg/cm^2/s is 272+/-40 sources/sq.deg. Four X-ray sources, corresponding to 8% of the total sample, have been detected in radio images with a flux limit of about 0.2 mJy. Careful statistical analysis of multicolour CCD data in the error boxes of the 50 X-ray sources has led to the identification of 42 sources, corresponding to 84% of the X-ray sample. These 42 reliable identifications are 33 AGNs (including two radio galaxies and one BL Lac candidate; 79% of the identified sources), 2 galaxies, 3 groups or clusters of galaxies and 4 stars. We also show that it is likely that a few of the 8 unidentified sources are such because the derived X-ray positions may be of...

  4. Optical technologies for extreme-ultraviolet and soft X-ray coherent sources

    Energy Technology Data Exchange (ETDEWEB)

    Canova, Federico [Amplitude Technologies, Evry (France); Poletto, Luca (ed.) [National Research Council, Padova (Italy). Inst. of Photonics and Nanotechnology

    2015-07-01

    The book reviews the most recent achievements in optical technologies for XUV and X-ray coherent sources. Particular attention is given to free-electron-laser facilities, but also to other sources available at present, such as synchrotrons, high-order laser harmonics and X-ray lasers. The optical technologies relevant to each type of source are discussed. In addition, the main technologies used for photon handling and conditioning, namely multilayer mirrors, adaptive optics, crystals and gratings are explained. Experiments using coherent light received during the last decades a lot of attention for the X-ray regime. Strong efforts were taken for the realization of almost fully coherent sources, e.g. the free-electron lasers, both as independent sources in the femtosecond and attosecond regimes and as seeding sources for free-electron-lasers and X-ray gas lasers. In parallel to the development of sources, optical technologies for photon handling and conditioning of such coherent and intense X-ray beams advanced. New problems were faced for the realization of optical components of beamlines demanding to manage coherent X-ray photons, e.g. the preservation of coherence and time structure of ultra short pulses.

  5. The Chandra Local Volume Survey: The X-ray Point Source Catalog of NGC 300

    CERN Document Server

    Binder, Breanna; Eracleous, Michael; Gaetz, Terrance J; Plucinsky, Paul P; Skillman, Evan D; Dalcanton, Julianne J; Anderson, Scott F; Weisz, Daniel R; Kong, Albert K H

    2012-01-01

    We present the source catalog of a new Chandra ACIS-I observation of NGC 300 obtained as part of the Chandra Local Volume Survey. Our 63 ks exposure covers ~88% of the D25 isophote (R~6.3 kpc) and yields a catalog of 95 X-ray point sources detected at high significance to a limiting unabsorbed 0.35-8 keV luminosity of ~10^36 erg s^-1. Sources were cross-correlated with a previous XMM-Newton catalog, and we find 75 "X-ray transient candidate" sources that were detected by one observatory, but not the other. We derive an X-ray scale length of 1.7+/-0.2 kpc and a recent star formation rate of 0.12 Msun yr^-1, in excellent agreement with optical observations. Deep, multi-color imaging from the Hubble Space Telescope, covering ~32% of our Chandra field, was used to search for optical counterparts to the X-ray sources, and we have developed a new source classification scheme to determine which sources are likely X-ray binaries, supernova remnants, and background AGN candidates. Finally, we present the X-ray luminos...

  6. Convertible source system of thermal neutron and X-ray at Hokkaido University electron linac facility

    Science.gov (United States)

    Kamiyama, T.; Hara, K. Y.; Taira, H.; Sato, H.

    2016-11-01

    The convertible source system for the neutron and the X-ray imagings was installed in the 45MeV electron linear accelerator facility at Hokkaido University. The source system is very useful for a complementary imaging. The imaging measurements for a sample were performed with both beams by using a vacuum tube type image intensifier. The enhanced contrast was obtained from the dataset of the radiograms measured with the neutron and X-ray beams.

  7. TRANSIENT X-RAY SOURCE POPULATION IN THE MAGELLANIC-TYPE GALAXY NGC 55

    Energy Technology Data Exchange (ETDEWEB)

    Jithesh, V.; Wang, Zhongxiang, E-mail: jithesh@shao.ac.cn [Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Road, Shanghai 200030 (China)

    2016-04-10

    We present the spectral and temporal properties of 15 candidate transient X-ray sources detected in archival XMM-Newton and Chandra observations of the nearby Magellanic-type, SB(s)m galaxy NGC 55. Based on an X-ray color classification scheme, the majority of the sources may be identified as X-ray binaries (XRBs), and six sources are soft, including a likely supernova remnant. We perform a detailed spectral and variability analysis of the data for two bright candidate XRBs. Both sources displayed strong short-term X-ray variability, and their X-ray spectra and hardness ratios are consistent with those of XRBs. These results, combined with their high X-ray luminosities (∼10{sup 38} erg s{sup −1}), strongly suggest that they are black hole (BH) binaries. Seven less luminous sources have spectral properties consistent with those of neutron star or BH XRBs in both normal and high-rate accretion modes, but one of them is the likely counterpart to a background galaxy (because of positional coincidence). From our spectral analysis, we find that the six soft sources are candidate super soft sources (SSSs) with dominant emission in the soft (0.3–2 keV) X-ray band. Archival Hubble Space Telescope optical images for seven sources are available, and the data suggest that most of them are likely to be high-mass XRBs. Our analysis has revealed the heterogeneous nature of the transient population in NGC 55 (six high-mass XRBs, one low-mass XRBs, six SSSs, one active galactic nucleus), helping establish the similarity of the X-ray properties of this galaxy to those of other Magellanic-type galaxies.

  8. [Experimental investigation of laser plasma soft X-ray source with gas target].

    Science.gov (United States)

    Ni, Qi-liang; Gong, Yan; Lin, Jing-quan; Chen, Bo; Cao, Jian-lin

    2003-02-01

    This paper describes a debris-free laser plasma soft X-ray source with a gas target, which has high operating frequency and can produce strong soft X-ray radiation. The valve of this light source is drived by a piezoelectrical ceramic whose operating frequency is up to 400 Hz. In comparison with laser plasma soft X-ray sources using metal target, the light source is debris-free. And it has higher operating frequency than gas target soft X-ray sources whose nozzle is controlled by a solenoid valve. A channel electron multiplier (CEM) operating in analog mode is used to detect the soft X-ray generated by the laser plasma source, and the CEM's output is fed to to a charge-sensitive preamplifier for further amplification purpose. Output charges from the CEM are proportional to the amplitude of the preamplifier's output voltage. Spectra of CO2, Xe and Kr at 8-14 nm wavelength which can be used for soft X-ray projection lithography are measured. The spectrum for CO2 consists of separate spectral lines originate mainly from the transitions in Li-like and Be-like ions. The Xe spectrum originating mainly from 4d-5f, 4d-4f, 4d-6p and 4d-5p transitions in multiply charged xenon ions. The spectrum for Kr consists of separate spectral lines and continuous broad spectra originating mainly from the transitions in Cu-, Ni-, Co- and Fe-like ions.

  9. 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

  10. Miniature, low-power X-ray tube using a microchannel electron generator electron source

    Science.gov (United States)

    Elam, Wm. Timothy (Inventor); Kelliher, Warren C. (Inventor); Hershyn, William (Inventor); DeLong, David P. (Inventor)

    2011-01-01

    Embodiments of the invention provide a novel, low-power X-ray tube and X-ray generating system. Embodiments of the invention use a multichannel electron generator as the electron source, thereby increasing reliability and decreasing power consumption of the X-ray tube. Unlike tubes using a conventional filament that must be heated by a current power source, embodiments of the invention require only a voltage power source, use very little current, and have no cooling requirements. The microchannel electron generator comprises one or more microchannel plates (MCPs), Each MCP comprises a honeycomb assembly of a plurality of annular components, which may be stacked to increase electron intensity. The multichannel electron generator used enables directional control of electron flow. In addition, the multichannel electron generator used is more robust than conventional filaments, making the resulting X-ray tube very shock and vibration resistant.

  11. A carbon nanotube field emission multipixel x-ray array source for microradiotherapy application

    Science.gov (United States)

    Wang, Sigen; Calderon, Xiomara; Peng, Rui; Schreiber, Eric C.; Zhou, Otto; Chang, Sha

    2011-05-01

    The authors report a carbon nanotube (CNT) field emission multipixel x-ray array source for microradiotherapy for cancer research. The developed multipixel x-ray array source has 50 individually controllable pixels and it has several distinct advantages over other irradiation source including high-temporal resolution (millisecond level), the ability to electronically shape the form, and intensity distribution of the radiation fields. The x-ray array was generated by a CNT cathode array (5×10) chip with electron field emission. A dose rate on the order of >1.2 Gy/min per x-ray pixel beam is achieved at the center of the irradiated volume. The measured dose rate is in good agreement with the Monte Carlo simulation result.

  12. Electron optics simulation for designing carbon nanotube based field emission x-ray source

    Science.gov (United States)

    Sultana, Shabana

    In this dissertation, electron optics simulation for designing carbon nanotube (CNT) based field emission x-ray source for medical imaging applications will be presented. However, for design optimization of x-ray tubes accurate electron beam optics simulation is essential. To facilitate design of CNT x-ray sources a commercial 3D finite element software has been chosen for extensive simulation. The results show that a simplified model of uniform electron field emission from the cathode surface is not sufficient when compared to experimental measurements. This necessitated the development of a refined model to describe a macroscopic field emission CNT cathode for electron beam optics simulations. The model emulates the random distribution of CNTs and the associated variation of local field enhancement factor. The main parameter of the model has been derived empirically from the experimentally measured I-V characteristics of the CNT cathode. Simulation results based on this model agree well with experiments which include measurements of the transmission rate and focus spot size. The model provides a consistent simulation platform for optimization of electron beam optics in CNT x-ray source design. A systematic study of electron beam optics in CNT x-ray tubes led to the development of a new generation of compact x-ray source with multiple pixels. A micro focus field emission x-ray source with a variable focal spot size has been fully characterized and evaluated. It has been built and successfully integrated into micro-CT scanners which are capable of dynamic cardiac imaging of free-breathing small animals with high spatial and temporal resolutions. In addition a spatially distributed high power multi-beam x-ray source has also been designed and integrated into a stationary digital breast tomosynthesis (s-DBT) configuration. This system has the potential to reduce the total scan time to 4 seconds and yield superior image quality in breast imaging.

  13. Symbiotic Stars in X-rays. II. Faint Sources Detected with XMM-Newton and Chandra

    Science.gov (United States)

    Nunez, N. E.; Luna, G. J. M.; Pillitteri, I.; Mukai, K.

    2014-01-01

    We report the detection from four symbiotic stars that were not known to be X-ray sources. These four object show a ß-type X-ray spectrum, that is, their spectra can be modeled with an absorbed optically thin thermal emission with temperatures of a few million degrees. Photometric series obtained with the Optical Monitor on board XMM-Newton from V2416 Sgr and NSV 25735 support the proposed scenario where the X-ray emission is produced in a shock-heated region inside the symbiotic nebulae.

  14. The Coherent X-ray Imaging instrument at the Linac Coherent Light Source

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Mengning; Williams, Garth J.; Messerschmidt, Marc; Seibert, M. Marvin; Montanez, Paul A.; Hayes, Matt; Milathianaki, Despina; Aquila, Andrew; Hunter, Mark S.; Koglin, Jason E.; Schafer, Donald W.; Guillet, Serge; Busse, Armin; Bergan, Robert; Olson, William; Fox, Kay; Stewart, Nathaniel; Curtis, Robin; Miahnahri, Alireza Alan; Boutet, Sébastien, E-mail: sboutet@slac.stanford.edu [Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States)

    2015-04-15

    Description of the Coherent X-ray Imaging (CXI) instrument at the Linac Coherent Light Source. Recent scientific highlights illustrate the femtosecond crystallography, high power density and extreme matter capabilities of the CXI instrument. The Coherent X-ray Imaging (CXI) instrument specializes in hard X-ray, in-vacuum, high power density experiments in all areas of science. Two main sample chambers, one containing a 100 nm focus and one a 1 µm focus, are available, each with multiple diagnostics, sample injection, pump–probe and detector capabilities. The flexibility of CXI has enabled it to host a diverse range of experiments, from biological to extreme matter.

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

    Science.gov (United States)

    Stoeckl, C.; Theobald, W.; Regan, S. P.; Romanofsky, M. H.

    2016-11-01

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

  16. X-Ray Sources and High-Throughput Data Collection Methods

    Energy Technology Data Exchange (ETDEWEB)

    Snell, Gyorgy

    2012-03-15

    X-ray diffraction experiments on protein crystals are at the core of the structure determination process. An overview of X-ray sources and data collection methods to support structure-based drug design (SBDD) efforts is presented in this chapter. First, methods of generating and manipulating X-rays for the purpose of protein crystallography, as well as the components of the diffraction experiment setup are discussed. SBDD requires the determination of numerous protein-ligand complex structures in a timely manner, and the second part of this chapter describes how to perform diffraction experiments efficiently on a large number of crystals, including crystal screening and data collection.

  17. The Soft X-ray Research instrument at the Linac Coherent Light Source

    Energy Technology Data Exchange (ETDEWEB)

    Dakovski, Georgi L., E-mail: dakovski@slac.stanford.edu; Heimann, Philip; Holmes, Michael [Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States); Krupin, Oleg [Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States); European XFEL, Notkestrasse 85, 22607 Hamburg (Germany); Minitti, Michael P.; Mitra, Ankush; Moeller, Stefan; Rowen, Michael; Schlotter, William F.; Turner, Joshua J. [Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States)

    2015-04-02

    A description of the Soft X-ray Research instrument (SXR) at the Linac Coherent Light Source is given. Recent scientific highlights illustrate the wide variety of experiments and detectors that can be accommodated at SXR. The Soft X-ray Research instrument provides intense ultrashort X-ray pulses in the energy range 280–2000 eV. A diverse set of experimental stations may be installed to investigate a broad range of scientific topics such as ultrafast chemistry, highly correlated materials, magnetism, surface science, and matter under extreme conditions. A brief description of the main instrument components will be given, followed by some selected scientific highlights.

  18. Development of a Novel Tunable X-Ray Source for the RPI-LINAC

    Energy Technology Data Exchange (ETDEWEB)

    Y. Danon; R.C. Block

    2004-11-30

    This document summarizes the results of a three year effort to develop a parametric x-ray (PXR) source. The emphasis of this research was to demonstrate production of high yield monoenergetic x-rays. Production of PXR is accomplished by placing a crystal in a relativistic electron beam. The process was first demonstrated in 1985 in Russia. Numerous papers were written about the characteristics of PXR from both experimental and theoretical perspectives. The advantage of PXR over other monoenergetic x-ray sources is that it is produced at large angle relative to the electron beam and at high intensity. None of the previous work described in the literature capitalized on this effect to study what is required in order to generate an effective monoenergetic x-ray source that can be used for practical applications. The work summarized here describes the process done in order to optimize the PXR production process by selecting an appropriate crystal and the optimal conditions. The research focused on production of 18 keV x-rays which are suitable for mammography however the results are not limited to this application or energy range. We are the first group to demonstrate x-ray imaging using PXR. Such sources can improve current medical imaging modalities. More research is required in order to design a prototype of a compact source.

  19. Faint X-ray Sources in the Globular Cluster Terzan 5

    CERN Document Server

    Heinke, C O; Cohn, H N; Lugger, P M; Grindlay, J E; Pooley, D; Lewin, W H G

    2006-01-01

    We report our analysis of a Chandra X-ray observation of the rich globular cluster Terzan 5, in which we detect 50 sources to a limiting 1.0-6 keV X-ray luminosity of 3*10^{31} ergs/s within the half-mass radius of the cluster. Thirty-three of these have L_X>10^{32} ergs/s, the largest number yet seen in any globular cluster. In addition to the quiescent low-mass X-ray binary (LMXB, identified by Wijnands et al.), another 12 relatively soft sources may be quiescent LMXBs. We compare the X-ray colors of the harder sources in Terzan 5 to the Galactic Center sources studied by Muno and collaborators, and find the Galactic Center sources to have harder X-ray colors, indicating a possible difference in the populations. We cannot clearly identify a metallicity dependence in the production of low-luminosity X-ray binaries in Galactic globular clusters, but a metallicity dependence of the form suggested by Jordan et al. for extragalactic LMXBs is consistent with our data.

  20. Transient X-ray source population in the Magellanic-type galaxy NGC 55

    CERN Document Server

    Jithesh, V

    2016-01-01

    We present the spectral and temporal properties of 15 candidate transient X-ray sources detected in archival {\\it XMM-Newton} and {\\it Chandra} observations of the nearby Magellanic-type, SB(s)m galaxy NGC 55. On the basis of an X-ray color classification scheme, the majority of the sources may be identified as X-ray binaries (XRBs), and six sources are soft, including a likely supernova remnant. We perform a detailed spectral and variability analysis of the data for two bright candidate XRBs. Both sources displayed strong short-term X-ray variability, and their X-ray spectra and hardness ratios are consistent with those of XRBs. These results, combined with their high X-ray luminosities ($\\sim 10^{38}~\\rm erg~s^{-1}$), strongly suggest that they are black hole (BH) binaries. Seven less luminous sources have spectral properties consistent with those of neutron star or BH XRBs in both normal and high-rate accretion modes, but one of them is the likely counterpart to a background galaxy (because of positional c...

  1. Characteristics of a high brightness gaseous field ion source employing tungsten-carbon doped NiAl needles

    Energy Technology Data Exchange (ETDEWEB)

    Mousa, Marwan S., E-mail: mmousa@mutah.edu.jo [Department of Physics, Mu' tah University, P.O. Box 7, Al-Karak (Jordan)

    2011-05-15

    We report on the characterization of a high brightness gaseous field ion source using an emitter made of a NiAl needle containing tiny spherical tungsten-carbon precipitates. By field evaporation of such a multiphase alloy, a surface protrusion is formed out of a precipitate, which can act as a small source size field ion emitter. The emission current-voltage characteristics of this emitter were recorded for a variety of parameters. The results obtained suggest that its application as a stable ion source is possible even on long term operation. -- Research highlights: {yields} High brightness gaseous field ion source of precipitation hardened NiAl+W+C emitter. {yields} Emission current-voltage characteristics are recorded for a variety of parameters. {yields} Very small virtual source sizes and energy spreads can be attained. {yields} Results suggest that application as long term stable ion source is possible.

  2. Chandra Resolves Cosmic X-ray Glow and Finds Mysterious New Sources

    Science.gov (United States)

    2000-01-01

    While taking a giant leap towards solving one of the greatest mysteries of X-ray astronomy, NASA's Chandra X-ray Observatory also may have revealed the most distant objects ever seen in the universe and discovered two puzzling new types of cosmic objects. Not bad for being on the job only five months. Chandra has resolved most of the X-ray background, a pervasive glow of X-rays throughout the universe, first discovered in the early days of space exploration. Before now, scientists have not been able to discern the background's origin, because no X-ray telescope until Chandra has had both the angular resolution and sensitivity to resolve it. "This is a major discovery," said Dr. Alan Bunner, Director of NASA's Structure andEvolution of the universe science theme. "Since it was first observed thirty-seven years ago, understanding the source of the X-ray background has been aHoly Grail of X-ray astronomy. Now, it is within reach." The results of the observation will be discussed today at the 195th national meeting of the American Astronomical Society in Atlanta, Georgia. An article describing this work has been submitted to the journal Nature by Dr. Richard Mushotzky, of NASA Goddard Space Flight Center, Greenbelt, Md., Drs. Lennox Cowie and Amy Barger at the University of Hawaii, Honolulu, and Dr. Keith Arnaud of the University of Maryland, College Park. "We are all very excited by this finding," said Mushotzky. "The resolution of most of the hard X-ray background during the first few months of the Chandra mission is a tribute to the power of this observatory and bodes extremely well for its scientific future," Scientists have known about the X-ray glow, called the X-ray background, since the dawn of X-ray astronomy in the early 1960s. They have been unable to discern its origin, however, for no X-ray telescope until Chandra has had both the angular resolution and sensitivity to resolve it. The German-led ROSAT mission, now completed, resolved much of the lower

  3. Derivation of total filtration thickness for diagnostic x-ray source assembly

    Science.gov (United States)

    Sekimoto, Michiharu; Katoh, Yoh

    2016-08-01

    The method defined by the IEC 60522 for determining the inherent filtration of an x-ray source device is applicable only for a limited range of tube voltage. Because the users cannot legally remove the x-ray movable diaphragm of the x-ray source device, total filtration, which is the sum of the additional filtration diaphragm movable for specific filtration and x-ray, cannot be measured. We develop a method for simply obtaining the total filtration for different tube voltage values. Total filtration can be estimated from a ratio R‧ of the air kerma Kx+T\\prime , which is measured with an Al plate with thickness T, and Kx\\prime measured without an Al plate. The conditions of the target material of the x-ray source device are then entered into the Report 78 Spectrum Processor to calculate the air kerma K x and K x+T for Al thicknesses x and (x  +  T), respectively, to obtain R. The minimum value of x, which is the difference between the R and R‧, is the total filtration of the x-ray source device. The total filtration calculated using the industrial x-ray source device was within  ±1% in the 40-120 kV range. This method can calculate the total filtration using air kerma measurements with and without the Al plate. Therefore, the load on the x-ray tube can be reduced, and preparation of multiple Al plates is not necessary. Furthermore, for the 40-120 kV tube voltage range, the user can easily measure the total filtration.

  4. Optical Identifications of Companion Soft X-ray Sources of Mrk 231

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    We present optical identification results for four ROSAT PSPC soft X-ray companions of Mrk 231 based on the deep BATC 6660 A-band image and the optical spectra obtained by the 60/90cm Schmidt telescope and the 2.16mtelescope at the Xinglong Station, NAOC. Three optical counterparts are quasarswith redshifts z > 1 and the remaining X-ray source is probably a background galaxycluster. Therefore, none of these soft X-ray companions are physically connectedwith the central X-ray source Mrk 231. Incorporating the previous results of Arp 220and Mrk 273 (Xia et al. 1998, 1999), we suggest that the apparent soft X-rayassociations with ULIRGs are chance coincidence in most cases.

  5. Laboratory source based full-field x-ray microscopy at 9 keV

    Energy Technology Data Exchange (ETDEWEB)

    Fella, C.; Balles, A.; Wiest, W. [Lehrstuhl für Röntgenmikroskopie, Julius-Maximilians-Universität, 97074 Würzburg (Germany); Zabler, S.; Hanke, R. [Lehrstuhl für Röntgenmikroskopie, Julius-Maximilians-Universität, 97074 Würzburg (Germany); Fraunhofer Development Center X-Ray Technology (EZRT), Flugplatzstrasse 75, 90768 Fürth (Germany)

    2016-01-28

    In the past decade, hard x-ray transmission microscopy experienced tremendous developments. With the avail-ability of efficient Fresnel zone plates, even set-ups utilizing laboratory sources were developed [1]. In order to improve the performance of these x-ray microscopes, novel approaches to fabricate optical elements [2] and brighter x-ray tubes [3] are promising candidates. We are currently building a laboratory transmission x-ray microscope for 9.25 keV, using an electron impact liquid-metal-jet anode source. Up to now, the further elements of our setup are: a polycapillary condenser, a tungsten zone plate, and a scintillator which is optically coupled to a CMOS camera. However, further variations in terms of optical elements are intended. Here we present the current status of our work, as well as first experimental results.

  6. Fourth-generation X-ray sources: some possible applications to biology.

    Science.gov (United States)

    Doniach, S

    2000-05-01

    The term 'fourth generation X-ray sources' has come to mean X-ray free-electron lasers which use multi-GeV electron beams from linear accelerators to generate X-rays by self-amplified stimulated emission when fired into long undulators. Properties of the radiation expected from such sources are reviewed briefly and two possible applications of the resulting pulsed highly collimated X-radiation to problems in biology are discussed: use of X-ray photon correlation spectroscopy to measure time correlations of atoms in protein crystals, and use of Mössbauer radiation extracted from the photon beams by resonant Bragg diffraction from (57)Fe-containing crystals, for MAD phasing of very large unit-cell biomolecular crystals and possibly for photon echo measurements.

  7. Evidence for Quasi-periodic X-Ray Dips from an Ultraluminous X-Ray Source: Implications for the Binary Motion

    CERN Document Server

    Pasham, Dheeraj R

    2013-01-01

    We report results from long-term (approximately 1240 days) X-ray (0.3-8.0 keV) monitoring of the ultraluminous X-ray source NGC 5408 X-1 with the Swift/X-Ray Telescope. Here we expand on earlier work by Strohmayer (2009) who used only a part of the present data set. Our primary results are: (1) the discovery of sharp, quasi-periodic, energy-independent dips in the X-ray intensity that recur on average every 243 days, (2) the detection of an energy-dependent (variability amplitude decreases with increasing energy), quasi-sinusoidal X-ray modulation with a period of 112.6+-4 days the amplitude of which weakens during the second half of the light curve and (3) spectral evidence for an increase in photoelectric absorption during the last continuous segment of the data. We interpret the X-ray modulations within the context of binary motion in analogy to that seen in high-inclination accreting X-ray binaries. If correct, this implies that NGC 5408 X-1 is in a binary with an orbital period of 243+-23 days, in contra...

  8. The X-ray Binary Population of the Nearby Dwarf Starburst Galaxy IC 10: Variable and Transient X-ray Sources

    CERN Document Server

    Laycock, Silas G T; Williams, Benjamin F; Prestwich, Andrea; Binder, Breanna; Christodoulou, Dimitris M

    2016-01-01

    We have monitored the Cassiopeia dwarf galaxy (IC 10) in a series of 10 Chandra ACIS-S observations to capture its variable and transient X-ray source population, which is expected to be dominated by High Mass X-ray Binaries (HMXBs). We present a sample of 21 X-ray sources that are variable between observations at the 3 sigma level, from a catalog of 110 unique point sources. We find 4 transients (flux variability ratio greater than 10) and a further 8 objects with ratio > 5. The observations span years 2003 - 2010 and reach a limiting luminosity of >10$^{35}$ erg/s, providing sensitivity to X-ray binaries in IC 10 as well as flare stars in the foreground Milky Way. The nature of the variable sources is investigated from light-curves, X-ray spectra, energy quantiles, and optical counterparts. The purpose of this study is to discover the composition of the X-ray binary population in a young starburst environment. IC 10 provides a sharp contrast in stellar population age (<10 My) when compared to the Magella...

  9. Ultraviolet spectroscopy of the supersoft X-ray source RX J0439.8-6809

    Science.gov (United States)

    Van Teeseling, Andre

    1997-07-01

    Observationally, supersoft X-ray sources are classified as near-Eddington stellar objects with almost all emission at energies blue star in the LMC. A 3sigma upper limit to the peak-to-peak optical variability is 0.07 mag. Of all optically identified supersoft X-ray sources, RX J0439.8-6809 has the lowest optical-to-X-ray flux ratio. The nature of RX J0439.8-6809 is still unknown. It might be the hottest known pre-white dwarf, suffering a late helium shell flash. Alternatively, RX J0439.8-6809 could be an accreting binary, in which case it might be the first known double-degenerate supersoft X-ray source with a predicted orbital period of only a few minutes. An ultraviolet spectrum is essential to distinguish between these two spectacular possibilities, and to bridge the gap between the X-ray and optical observations. Such a spectrum can only be obtained with the HST STIS. Therefore, we propose to obtain two ultraviolet spectra, which will test the assumption that the optical spectrum is the Rayleigh-Jeans tail of the soft X-ray component, which will determine the spectral energy distribution, and which may provide the first direct evidence for accretion in this source by detecting an excess in the ultraviolet or ultraviolet emission lines like N V Lambda 1240.

  10. Optical Synchronization Systems for Femtosecond X-raySources

    Energy Technology Data Exchange (ETDEWEB)

    Wilcox, Russell; Staples, John W.; Holzwarth, Ronald

    2004-05-09

    In femtosecond pump/probe experiments using short X-Ray and optical pulses, precise synchronization must be maintained between widely separated lasers in a synchrotron or FEL facility. We are developing synchronization systems using optical signals for applications requiring different ranges of timing error over 100 meter of glass fiber. For stabilization in the hundred femtosecond range a CW laser is amplitude modulated at 1 10 GHz, the signal retroreflected from the far end, and the relative phase used to correct the transit time with a piezoelectric phase modulator. For the sub-10 fsec range the laser frequency itself is upshifted 55 MHz with an acousto-optical modulator, retroreflected, upshifted again and phase compared at the sending end to a 110 MHz reference. Initial experiments indicate less than 1 fsec timing jitter. To lock lasers in the sub-10 fs range we will lock two single-frequency lasers separated by several tera Hertz to a master modelocked fiber laser, transmit the two frequencies over fiber, and lock two comb lines of a slave laser to these frequencies, thus synchronizing the two modelocked laser envelopes.

  11. Optical Synchronization Systems for Femtosecond X-Ray Sources

    CERN Document Server

    Wilcox, Russell; Staples, John W

    2005-01-01

    In femtosecond pump/probe experiments using short x-ray and optical pulses, precise synchronization must be maintained between widely separated lasers in a synchrotron or FEL facility. We are developing synchronization systems using optical signals for applications requiring different ranges of timing error. For the sub-100fs range we use an amplitude modulated CW laser at 1GHz to transmit RF phase information, and control the delay through a 100m fiber by observing the retroreflected signal. Initial results show 40fs peak-to-peak error above 10Hz, and 200fs long term drift, mainly due to amplitude sensitivity in the analog mixers. For the sub-10fs range we will lock two single-frequency lasers separated by several teraHertz to a master modelocked fiber laser, transmit the two frequencies over fiber, and lock two comb lines of a slave laser to these frequencies, thus synchronizing the two modelocked laser envelopes. For attosecond synchronization we propose a stabilized, free space link using bulk lens wavegu...

  12. X-ray phase imaging with a laboratory source using selective reflection from a mirror.

    Science.gov (United States)

    Pelliccia, Daniele; Paganin, David M

    2013-04-22

    A novel approach for hard x-ray phase contrast imaging with a laboratory source is reported. The technique is based on total external reflection from the edge of a mirror, aligned to intercept only half of the incident beam. The mirror edge thus produces two beams. The refraction x-rays undergo when interacting with a sample placed before the mirror, causes relative intensity variations between direct and reflected beams. Quantitative phase contrast and pure absorption imaging are demonstrated using this method.

  13. The SPARX Project: R & D Activity Towards X-Rays FEL Sources

    Energy Technology Data Exchange (ETDEWEB)

    Alesini, D.; Bellaveglia, M.; Bertolucci, S.; Biagini, M.E.; Boni, R.; Boscolo, M.; Castellano, M.; Clozza, A.; Di Pirro, G.; Drago, A.; Esposito, A.; Ferrario, M.; Filippetto, D.; Fusco, V.; Gallo, A.; Ghigo, A.; Guiducci, S.; Incurvati, M.; Ligi, C.; Marcellini, F.; Migliorati, M.; /Frascati /ENEA, Frascati /INFN, Milan /INFN, Rome /INFN,

    2005-08-05

    SPARX is an evolutionary project proposed by a collaboration among ENEA-INFN-CNR-Universita di Roma Tor Vergata aiming at the construction of a FELSASE X-ray source in the Tor Vergata Campus. The first phase of the SPARX project, funded by Government Agencies, will be focused on R&D activity on critical components and techniques for future X-ray facilities as described in this paper.

  14. AM CVn systems as optical, X-ray and GWR sources

    NARCIS (Netherlands)

    Yungelson, L.; Nelemans, G.; Portegies Zwart, S.F.; Tovmassian, G.; Sion, E.

    2004-01-01

    We discuss the model for the Galactic sample of the AM CVn systems with P[orb] ≤ 1500 s that can be detected in the optical and/or X-ray bands and may be resolved by the gravitational waves detector LISA. At 3 ≲P ≲ 10 min all detectable systems are X-ray sources. At P ≳ 10 min most systems are only

  15. Populations of Bright X-ray Sources in the Starburst Galaxies NGC 4038/4039

    Institute of Scientific and Technical Information of China (English)

    Xi-Wei Liu; Xiang-Dong Li

    2007-01-01

    Assuming a naive star formation history,we construct synthetic X-ray source populations.using a population synthesis code,for comparison with the observed X-ray luminosity function (XLF) of the interacting galaxies NGC 4038/4039.We have included highand intermediate-mass X-ray binaries.young rotation-powered pulsars and fallback disk-fed black holes in modeling the bright X-ray sources detected.We find that the majority of the X-ray sources are likely to be intermediate-mass X-ray binaries.but for typical binary evolution parameters.the predicted XLF seems to be steeper than observed.We note that the shape of the XLFs depends critically on the existence of XLF break for young populations.and suggest super-Eddington accretion luminosities or the existence of intermediate-mass black holes to account for the high luminosity end and the slope of the XLF in NGC 4038/4039.

  16. Interactions between radio sources and X-ray gas at the centers of cooling core clusters

    Science.gov (United States)

    Sarazin, C. L.; Blanton, E. L.; Clarke, T. E.

    Recent Chandra and XMM observations of the interaction of central radio sources and cooling cores in clusters of galaxies will be presented. The clusters studied include A262, A2052, A2626, A113, A2029, A2597, and A4059. The radio sources blow "bubbles" in the X-ray gas, displacing the gas and compressing it into shells around the radio lobes. At the same time, the radio sources are confined by the X-ray gas. At larger radii, "ghost bubbles" are seen which are weak in radio emission except at low frequencies. These may be evidence of previous eruptions of the radio sources. In some cases, buoyantly rising bubbles may entrain cooler X-ray gas from the centers of the cooling cores. Some radio sources previously classified as cluster merger radio relics may actually be displaced radio bubbles from the central radio sources. The relation between the radio bubbles, and cooler gas (10 keV).

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

    Energy Technology Data Exchange (ETDEWEB)

    Zucchini, F.; Chauvin, C.; Combes, P.; Sol, D.; Loyen, A.; Roques, B.; Grunenwald, J. [CEA, DAM, GRAMAT, F-46500 Gramat (France); Bland, S. N. [Blackett Laboratory, Imperial College, London SW7 2BW (United Kingdom)

    2015-03-15

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

  18. Optical technologies for extreme-ultraviolet and soft X-ray coherent sources

    CERN Document Server

    Poletto, Luca

    2015-01-01

    The book reviews the most recent achievements in optical technologies for XUV and X-ray coherent sources. Particular attention is given to free-electron-laser facilities, but also to other sources available at present, such as synchrotrons, high-order laser harmonics and X-ray lasers. The optical technologies relevant to each type of source are discussed. In addition, the main technologies used for photon handling and conditioning, namely multilayer mirrors, adaptive optics, crystals and gratings are explained. Experiments using coherent light received during the last decades a lot of attention for the X-ray regime. Strong efforts were taken for the realization of almost fully coherent sources, e.g. the free-electron lasers, both as independent sources in the femtosecond and attosecond regimes and as seeding sources for free-electron-lasers and X-ray gas lasers. In parallel to the development of sources, optical technologies for photon handling and conditioning of such coherent and intense X-ray beams advance...

  19. Laboratory-size three-dimensional x-ray microscope with Wolter type I mirror optics and an electron-impact water window x-ray source.

    Science.gov (United States)

    Ohsuka, Shinji; Ohba, Akira; Onoda, Shinobu; Nakamoto, Katsuhiro; Nakano, Tomoyasu; Miyoshi, Motosuke; Soda, Keita; Hamakubo, Takao

    2014-09-01

    We constructed a laboratory-size three-dimensional water window x-ray microscope that combines wide-field transmission x-ray microscopy with tomographic reconstruction techniques, and observed bio-medical samples to evaluate its applicability to life science research fields. It consists of a condenser and an objective grazing incidence Wolter type I mirror, an electron-impact type oxygen Kα x-ray source, and a back-illuminated CCD for x-ray imaging. A spatial resolution limit of around 1.0 line pairs per micrometer was obtained for two-dimensional transmission images, and 1-μm scale three-dimensional fine structures were resolved.

  20. Chandra Studies of Unidentified X-ray Sources in the Galactic Bulge

    Science.gov (United States)

    Mori, Hideyuki

    2013-09-01

    We propose to study a complete X-ray sample in the luminosity range of > 10^34 erg s^-1 in the Galactic bulge, including 5 unidentified sources detected in the ROSAT All Sky Survey. Our goal is to obtain a clear picture about X-ray populations in the bulge, by utilizing the excellent Chandra position accuracy leading to unique optical identification together with the X-ray spectral properties. This is a new step toward understanding the formation history of the bulge. Furthermore, because the luminosity range we observe corresponds to a ``missing link'' region ever studied for a neutron star or blackhole X-ray binary, our results are also unique to test accretion disk theories at intermediate mass accretion rates.

  1. A CCD area detector for X-ray diffraction under high pressure for rotating anode source

    Indian Academy of Sciences (India)

    Amar Sinha; Alka B Garg; V Vijayakumar; B K Godwal; S K Sikka

    2000-04-01

    Details of a two-dimensional X-ray area detector developed using a charge coupled device, a image intensifier and a fibre optic taper are given. The detector system is especially optimized for angle dispersive X-ray diffraction set up using rotating anode generator as X-ray source. The performance of this detector was tested by successfully carrying out powder X-ray diffraction measurements on various materials such as intermetallics AuIn2, AuGa2, high material Pd and low scatterer adamantane (C10H16) at ambient conditions. Its utility for quick detection of phase transitions at high pressures with diamond anvil cell is demonstrated by reproducing the known pressure induced structural transitions in RbI, KI and a new structural phase transition in AuGa2 above 10 GPa. Various softwares have also been developed to analyze data from this detector.

  2. Progress Towards A Dedicated Synchrotron Radiation Source For Ultrafast X-Ray Science

    Science.gov (United States)

    Lidia, Steve

    2002-03-01

    We present progress towards the design of a femtosecond synchrotron radiation x-ray source based on a flat-beam rf gun and a recirculating superconducting linac that provides beam to an array of undulators and bend magnets. Optical pulse durations of <100 fs are obtained by a combination of electron pulse compression, transverse temporal correlation of the electrons, and x-ray pulse compression. After an introduction and initial scientific motivation, we cover the following aspects of the design: layout and lattice, ultra-fast x-ray pulse production, flat electron-beam production, the rf gun, rf systems, cryogenic systems, collective effects, photon production, and synchronization of x-ray and laser pulses. We conclude with a summary of issues and areas of development that remain to be addressed.

  3. LUX: a design study for a linac-/laser-based ultrafast x-ray source

    Science.gov (United States)

    Corlett, John N.; Barletta, William A.; DeSantis, Stefano; Doolittle, Larry; Fawley, William M.; Heimann, Philip; Leone, Stephen; Lidia, Steven; Li, Derun; Penn, Gregory; Ratti, Alex; Reinsch, Matheus; Schoenlein, Robert; Staples, John; Stover, Gregory; Virostek, Steve; Wan, Weishi; Wells, Russell; Wilcox, Russell; Wolski, Andy; Wurtele, Jonathan; Zholents, Alexander A.

    2004-11-01

    We describe the design concepts for a potential future source of femtosecond x-ray pulses based on synchrotron radiation production in a recirculating electron linac. Using harmonic cascade free-electron lasers (FEL's) and spontaneous emission in short-period, narrow-gap insertion devices, a broad range of photon energies are available with tunability from EUV to hard x-ray regimes. Photon pulse durations are controllable and range from 10 fs to 200 fs, with fluxes 107-1012 photons per pulse. Full spatial and temporal coherence is obtained for EUV and soft X-rays. A fiber laser master oscillator and stabilized timing distribution scheme are proposed to synchronize accelerator rf systems and multiple lasers throughout the facility, allowing timing synchronization between sample excitation and X-ray probe of approximately 20-50 fs.

  4. Soft x-ray source for nanostructure imaging using femtosecond-laser-irradiated clusters

    Science.gov (United States)

    Fukuda, Y.; Faenov, A. Ya.; Pikuz, T.; Kando, M.; Kotaki, H.; Daito, I.; Ma, J.; Chen, L. M.; Homma, T.; Kawase, K.; Kameshima, T.; Kawachi, T.; Daido, H.; Kimura, T.; Tajima, T.; Kato, Y.; Bulanov, S. V.

    2008-03-01

    The intense soft x-ray light source using the supersonic expansion of the mixed gas of He and CO2, when irradiated by a femtosecond Ti:sapphire laser pulse, is observed to enhance the radiation of soft x-rays from the CO2 clusters. Using this soft x-ray emissions, nanostructure images of 100-nm-thick Mo foils in a wide field of view (mm2 scale) with high spatial resolution (800nm ) are obtained with high dynamic range LiF crystal detectors. The local inhomogeneities of soft x-ray absorption by the nanometer-thick foils is measured with an accuracy of less than ±3%.

  5. Initial feasibility study of a dedicated synchrotron radiation light source for ultrafast X-ray science

    Energy Technology Data Exchange (ETDEWEB)

    Corlett, John N.; DeSantis, S.; Hartman, N.; Heimann, P.; LaFever, R.; Li, D.; Padmore, H.; Rimmer, R.; Robinson, K.; Schoenlein, R.; Tanabe, J.; Wang, S.; Zholents, A.; Kairan, D.

    2001-10-26

    We present an initial feasibility summary of a femtosecond synchrotron radiation x-ray source based on a flat-beam rf gun and a recirculating superconducting linac that provides beam to an array of undulators and bend magnets. Optical pulse durations of < 100 fs are obtained by a combination of electron pulse compression, transverse temporal correlation of the electrons, and x-ray pulse compression. After an introduction and initial scientific motivation, we cover the following aspects of the design: layout and lattice, ultra-fast x-ray pulse production, flat electron-beam production, the rf gun, rf systems, cryogenic systems, collective effects, photon production, and synchronization of x-ray and laser pulses. We conclude with a summary of issues and areas of development that remain to be addressed.

  6. Calibration Of A KrF Laser-Plasma Source For X-Ray Microscopy Applications

    Science.gov (United States)

    Turcu, I. C. E.; O'Neill, F.; Zammit, U.; Al-Hadithi, Y.; Eason, R. W.; Rogayski, A. M.; Hills, C. P. B.; Michette, A. G.

    1988-02-01

    Plasma X-ray sources for biological microscopy in the water-window have been produced by focusing tige 200 3, 50 ns Sprit q KrF laser onto carbon targets at irradiance between 2.2 x 10" W/cm4 and 3.7 x 10i3W/cm. Absolute measurements of X-ray production have been made using a calibrated, vacuum X-ray diode detector. A peak conversion efficiency . 10% is measured from KrF laseri)Tight tcto wate-window X-rays at 280 eV < hv < 530 eV for a target irradiance . 1 x x 10 W/cm'. Some measurements with gold and tungsten targets give conversion efficiencies 2$25% at a similar laser irradiance.

  7. Upgrade of X-band thermionic cathode RF gun for Compton scattering X-ray source

    Science.gov (United States)

    Taniguchi, Yoshihiro; Sakamoto, Fumito; Natsui, Takuya; Yamamoto, Tomohiko; Hashimoto, Eiko; Lee, KiWoo; Uesaka, Mitsuru; Yoshida, Mitsuhiro; Higo, Toshiyasu; Fukuda, Shigeki; Akemoto, Mitsuo

    2009-09-01

    A Compton scattering X-ray source consisting of an X-band (11.424 GHz) electron linear accelerator (linac) and Q-switched Nd: YAG laser is currently under development at the University of Tokyo. Monochromatic X-rays are required for a variety of medical and biological applications. The X-ray source produces monochromatic X-rays via collision between a 35-MeV multi-bunch (104 bunches in a 1 μs RF pulse) electron beam and 1.4 J/10 ns (532 nm) Nd: YAG laser pulse. The linac uses an X-band 3.5-cell thermionic cathode RF gun and an alpha magnet as an injector. Until now, electron beam generation (2 MeV, 1 pC/bunch at the exit of the injector), beam acceleration, and X-ray generation have been verified. In order to increase X-ray energy and intensity, we have completed the design and construction of a new RF gun with relevant modifications in some structures. In this paper, we describe the details of the concepts of designing a new RF gun and discuss future works.

  8. Old and Young X-ray Point Source Populations in Nearby Galaxies

    CERN Document Server

    Colbert, E; Ptak, A; Strickland, D K

    2004-01-01

    We analyzed 1441 Chandra X-ray point sources in 32 nearby galaxies. The total point-source X-ray luminosity L_XP is well correlated with B, K, and FIR+UV luminosities of spiral host galaxies, and with the B and K luminosities for ellipticals. This suggests an intimate connection between L_XP and both the old and young stellar populations, for which K and FIR+UV luminosities are proxies for the galaxy mass M and star-formation rate SFR. We derive proportionality constants 1.3E29 erg/s/Msol and 0.7E39 erg/s/(Msol/yr), which can be used to estimate the old and young components from M and SFR, respectively. The cumulative X-ray luminosity functions for the point sources have quite different slopes for the spirals (gamma ~= 0.5-0.8) and ellipticals (gamma ~= 1.4), implying *the most luminous point sources dominate L_XP* for the spirals. Most of the point sources have X-ray colors that are consistent with either LMXBs or Ultraluminous X-ray sources (ULXs a.k.a. IXOs) and we rule out classical HMXBs (e.g. neutron-st...

  9. Chandra Observation of the X-Ray Source Population of NGC 6946

    CERN Document Server

    Holt, S S; Hwang, U; Petre, R

    2003-01-01

    We present the results of a study of discrete X-ray sources in NGC 6946 using a deep Chandra ACIS observation. Based on the slope of the log N-log S distribution and the general correlation of sources with the spiral arms, we infer that the overall discrete source sample in NGC 6946 is dominated by high mass X-ray binaries, in contrast to the source distributions in M31 and the Milky Way. This is consistent with the higher star formation rate in NGC 6946 than in those galaxies. We find that the strong X-ray sources in the region of the galactic center do not correlate in detail with images of the region in the near-IR, although one of them may be coincident with the galactic center. The non-central ultra-luminous X-ray source in NGC 6946, previously identified with a supernova remnant, has an X-ray spectrum and luminosity that is inconsistent with either a traditional pulsar wind nebula or a blast wave remnant.

  10. A radio survey of supersoft, persistent and transient X-ray sources in the Magellanic Clouds

    CERN Document Server

    Fender, R P; Tzioumis, A K

    1998-01-01

    We present a radio survey of X-ray sources in the Large and Small Magellanic clouds with the Australia Telescope Compact Array at 6.3 and 3.5 cm. Specifically, we have observed the fields of five LMC and two SMC supersoft X-ray sources, the X-ray binaries LMC X-1, X-2, X-3 & X-4, the X-ray transient Nova SMC 1992, and the soft gamma-ray repeater SGR 0525-66. None of the targets are detected as point sources at their catalogued positions. In particular, the proposed supersoft jet source RXJ 0513-69 is not detected, placing constraints on its radio luminosity compared to Galactic jet sources. Limits on emission from the black hole candidate systems LMC X-1 and X-3 are consistent with the radio behaviour of persistent Galactic black hole X-ray binaries, and a previous possible radio detection of LMC X-1 is found to almost certainly be due to nearby field sources. The SNR N49 in the field of SGR 0525-66 is mapped at higher resolution than previously, but there is still no evidence for any enhanced emission or...

  11. Compact source of narrowband and tunable X-rays for radiography

    Energy Technology Data Exchange (ETDEWEB)

    Banerjee, Sudeep, E-mail: sbanejee2@unl.edu [Department of Physics and Astronomy, University of Nebraska, Lincoln, NE 68516 (United States); Chen, Shouyuan; Powers, Nathan; Haden, Daniel; Liu, Cheng; Golovin, G.; Zhang, Jun; Zhao, Baozhen [Department of Physics and Astronomy, University of Nebraska, Lincoln, NE 68516 (United States); Clarke, S.; Pozzi, S. [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI 48109 (United States); Silano, J.; Karwowski, H. [Department of Physics and Astronomy, University of North Carolina, Chapel Hill, NC 27599 (United States); Umstadter, Donald [Department of Physics and Astronomy, University of Nebraska, Lincoln, NE 68516 (United States)

    2015-05-01

    We discuss the development of a compact X-ray source based on inverse-Compton scattering with a laser-driven electron beam. This source produces a beam of high-energy X-rays in a narrow cone angle (5–10 mrad), at a rate of 10{sup 8} photons-s{sup −1}. Tunable operation of the source over a large energy range, with energy spread of ∼50%, has also been demonstrated. Photon energies >10 MeV have been obtained. The narrowband nature of the source is advantageous for radiography with low dose, low noise, and minimal shielding.

  12. The X-Ray Binary Population of the Nearby Dwarf Starburst Galaxy IC 10: Variable and Transient X-Ray Sources

    Science.gov (United States)

    Laycock, Silas; Cappallo, Rigel; Williams, Benjamin F.; Prestwich, Andrea; Binder, Breanna; Christodoulou, Dimitris M.

    2017-02-01

    We have monitored the Cassiopeia dwarf galaxy (IC 10) in a series of 10 Chandra ACIS-S observations to capture its variable and transient X-ray source population, which is expected to be dominated by High Mass X-ray Binaries (HMXBs). We present a sample of 21 X-ray sources that are variable between observations at the 3σ level, from a catalog of 110 unique point sources. We find four transients (flux variability ratio greater than 10) and a further eight objects with ratios >5. The observations span the years 2003–2010 and reach a limiting luminosity of >1035 erg s‑1, providing sensitivity to X-ray binaries in IC 10 as well as flare stars in the foreground Milky Way. The nature of the variable sources is investigated from light curves, X-ray spectra, energy quantiles, and optical counterparts. The purpose of this study is to discover the composition of the X-ray binary population in a young starburst environment. IC 10 provides a sharp contrast in stellar population age (<10 My) when compared to the Magellanic Clouds (40–200 My) where most of the known HMXBs reside. We find 10 strong HMXB candidates, 2 probable background Active Galactic Nuclei, 4 foreground flare-stars or active binaries, and 5 not yet classifiable sources. Complete classification of the sample requires optical spectroscopy for radial velocity analysis and deeper X-ray observations to obtain higher S/N spectra and search for pulsations. A catalog and supporting data set are provided.

  13. A JEM-X Catalog of X-ray Sources

    DEFF Research Database (Denmark)

    Westergaard, Niels Jørgen Stenfeldt

    2009-01-01

    . A search for weaker, persistent, sources has been done in deep mosaic images that have been produced with all available observations for a large number of sky regions. The two resulting catalogs hold 158 and 179 sources respectively, but the combined catalog consists of 209 sources. This catalog can...... be downloaded as a FITS binary table file with source information such as names, positions, and fluxes at the PoS web page for the conference....

  14. Common-source TLD and RADFET characterization of Co-60, Cs-137, and x-ray irradiation sources

    Energy Technology Data Exchange (ETDEWEB)

    Simons, M. [Research Triangle Inst., Research Triangle Park, NC (United States); Pease, R.L. [RLP Research, Albuquerque, NM (United States); Fleetwood, D.M. [Sandia National Labs., Albuquerque, NM (United States)] [and others

    1997-06-01

    Dose enhancement and dose rate were measured in more than a dozen gamma sources using pMOS RADFETs and TLDs from two independent sources. ARACOR X-ray dose rates were calibrated using single- and dual-dielectric RADFETs.

  15. Analysis of coronal and chromospheric hard X-ray sources in an eruptive solar flare

    Science.gov (United States)

    Zimovets, Ivan; Golovin, Dmitry; Livshits, Moisey; Vybornov, Vadim; Sadykov, Viacheslav; Mitrofanov, Igor

    We have analyzed hard X-ray emission of an eruptive solar flare on 3 November 2010. The entire flare region was observed by the STEREO-B spacecraft. This gave us an information that chromospheric footpoints of flare magnetic loops were behind the east solar limb for an earth observer. Hard X-ray emission from the entire flare region was detected by the High Energy Neutron Detector (HEND) onboard the 2001 Mars Odyssey spacecraft while hard X-rays from the coronal part of the flare region were detected by the RHESSI. This rare situation has allowed us to investigate both coronal and chromospheric sources of hard X-ray emission separately. Flare impulsive phase was accompanied by eruption of a magnetic flux rope and formation of a plasmoid detected by the AIA/SDO in the EUV range. Two coronal hard X-ray sources (S_{1} and S_{2}) were detected by the RHESSI. The upper source S_{1} coincided with the plasmoid and the lower source S_{2} was near the tops of the underlying flare loops that is in accordance with the standard model of eruptive flares. Imaging spectroscopy with the RHESSI has allowed to measure energetic spectra of hard X-ray emission from the S_{1} and S_{2} sources. At the impulsive phase peak they have power-law shape above ≈ 15 keV with spectral slopes gamma_{S_{1}}=3.46 ± 1.58 and gamma_{S_{2}}=4.64 ± 0.12. Subtracting spatially integrated spectrum of coronal hard X-ray emission measured by the RHESSI from the spectrum measured by the HEND we found spectrum of hard X-rays emitted from the footpoints of the flare loops (source S_{0}). This spectrum has a power-law shape with gamma_{S_{0}}=2.21 ± 0.57. It is shown that it is not possible to explain the measured spectra of the S_{2} and S_{0} sources in frames of the thin and thick target models respectively if we assume that electrons were accelerated in the energy release site situated below the plasmoid and above the flare loops as suggested by the standard flare model. To resolve the contradiction

  16. SIGMA discovery of a transient hard X-ray source in the galactic center region.

    Science.gov (United States)

    Vargas, M.; Goldwurm, A.; Paul, J.; Denis, M.; Borrel, V.; Bouchet, L.; Roques, J. P.; Jourdain, E.; Trudolyubov, S.; Gilfanov, M.; Churazov, E.; Sunyaev, R.; Khavenson, N.; Dyachkov, A.; Novikov, B.; Chulkov, I.

    1996-09-01

    A new X-ray transient source, GRS 1730-312 (=KS 1730-312), was discovered by the hard X-ray/soft γ-ray coded mask telescope SIGMA/GRANAT in the Galactic Center region during observations performed in September 1994. The flare started on September 22 and lasted approximately 3days, during which the source became the brightest object of the region at energies above 35keV. The average 35-200keV spectrum can be described by a power law with photon index of -2.5 or by a thermal bremsstrahlung model with kT_e_=~70keV. SIGMA data have been found consistent with the spectral shape and with the spectral evolution observed by the TTM/Mir-Kvant telescope at lower energies. This new source belongs to the population of hard X-ray sources already detected by SIGMA in the direction of the Galactic Bulge region.

  17. Luminous X-ray sources in spiral and star-forming galaxies.

    Science.gov (United States)

    Ward, Martin

    2002-09-15

    For studies of discrete X-ray source populations in nearby galaxies, high spatial resolution is a key to making progress. Now, for the first time, using the Chandra X-ray observatory, we are able to study these source populations in detail for galaxies beyond M31 and our local group galaxies. Analysis of accretion-driven and supernova-related discrete sources provides a new perspective on the evolution of galactic stellar populations, as well as giving insights into the physical mechanisms operating in individual cases. A particularly intriguing area, which we are only just beginning to address, is the nature of the most X-ray-luminous sources that are being discovered in many spiral and star-forming galaxies.

  18. Developing small vacuum spark as an x-ray source for calibration of an x-ray focusing crystal spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Ghomeishi, Mostafa; Adikan, Faisal Rafiq Mahamd [Photonic Research Group, Department of Electrical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia); Karami, Mohammad [Department of Mechanical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia)

    2012-10-15

    A new technique of x-ray focusing crystal spectrometers' calibration is the desired result. For this purpose the spectrometer is designed to register radiated copper K{alpha} and K{beta} lines by using a flat {alpha}-quartz crystal. This experiment uses pre-breakdown x-ray emissions in low vacuum of about 2.5-3 mbar. At this pressure the pinch will not form so the plasma will not radiate. The anode material is copper and the capacity of the capacitor bank is 22.6 nF. This experiment designed and mounted a repetitive triggering system to save the operator time making hundreds of shots. This emission amount is good for calibration and geometrical adjustment of an optical crystal x-ray focusing spectrometer.

  19. Developing small vacuum spark as an x-ray source for calibration of an x-ray focusing crystal spectrometer.

    Science.gov (United States)

    Ghomeishi, Mostafa; Karami, Mohammad; Adikan, Faisal Rafiq Mahamd

    2012-10-01

    A new technique of x-ray focusing crystal spectrometers' calibration is the desired result. For this purpose the spectrometer is designed to register radiated copper Kα and Kβ lines by using a flat α-quartz crystal. This experiment uses pre-breakdown x-ray emissions in low vacuum of about 2.5-3 mbar. At this pressure the pinch will not form so the plasma will not radiate. The anode material is copper and the capacity of the capacitor bank is 22.6 nF. This experiment designed and mounted a repetitive triggering system to save the operator time making hundreds of shots. This emission amount is good for calibration and geometrical adjustment of an optical crystal x-ray focusing spectrometer.

  20. Development of a microfocus x-ray tube with multiple excitation sources

    Science.gov (United States)

    Maeo, Shuji; Krämer, Markus; Taniguchi, Kazuo

    2009-03-01

    A microfocus x-ray tube with multiple targets and an electron gun with a focal spot size of 10 μm in diameter has been developed. The electron gun contains a LaB6 cathode and an Einzel lens. The x-ray tube can be operated at 50 W (50 kV, 1 mA) and has three targets, namely, Cr, W, and Rh on the anode that can be selected completely by moving the anode position. A focal spot size of 10 μm in diameter can be achieved at 0.5 mA current. As demonstration of the usability of a multiexcitation x-ray tube, the fluorescence x-rays have been measured using a powder specimen mixed of TiO2, Co, and Zr of the same quantity. The differences of excitation efficiency have clearly appeared according to the change in excitation source. From the results discussed here, it can be expected that the presented x-ray tube will be a powerful tool in microx-ray fluorescence spectrometers and various x-ray instruments.

  1. Quantitative X-Ray Phase-Contrast Microtomography from a Compact Laser Driven Betatron Source

    CERN Document Server

    Wenz, J; Khrennikov, K; Bech, M; Thibault, P; Heigoldt, M; Pfeiffer, F; Karsch, S

    2014-01-01

    X-ray phase-contrast imaging has recently led to a revolution in resolving power and tissue contrast in biomedical imaging, microscopy and materials science. The necessary high spatial coherence is currently provided by either large-scale synchrotron facilities with limited beamtime access or by microfocus X-ray tubes with rather limited flux. X-rays radiated by relativistic electrons driven by well-controlled high-power lasers offer a promising route to a proliferation of this powerful imaging technology. A laser-driven plasma wave accelerates and wiggles electrons, giving rise to brilliant keV X-ray emission. This so-called Betatron radiation is emitted in a collimated beam with excellent spatial coherence and remarkable spectral stability. Here we present the first phase-contrast micro-tomogram revealing quantitative electron density values of a biological sample using betatron X-rays, and a comprehensive source characterization. Our results suggest that laser-based X-ray technology offers the potential fo...

  2. A POPULATION OF ULTRALUMINOUS X-RAY SOURCES WITH AN ACCRETING NEUTRON STAR

    Energy Technology Data Exchange (ETDEWEB)

    Shao, Yong; Li, Xiang-Dong, E-mail: lixd@nju.edu.cn [Department of Astronomy, Nanjing University, Nanjing 210046 (China)

    2015-04-01

    Most ultraluminous X-ray sources (ULXs) are believed to be X-ray binary systems, but previous observational and theoretical studies tend to prefer a black hole rather than a neutron star (NS) accretor. The recent discovery of 1.37 s pulsations from the ULX M82 X-2 has established its nature as a magnetized NS. In this work we model the formation history of NS ULXs in an M82- or Milky Way (MW)-like Galaxy, by use of both binary population synthesis and detailed binary evolution calculations. We find that the birth rate is around 10{sup −4} yr{sup −1} for the incipient X-ray binaries in both cases. We demonstrate the distribution of the ULX population in the donor mass–orbital period plane. Our results suggest that, compared with black hole X-ray binaries, NS X-ray binaries may significantly contribute to the ULX population, and high-mass and intermediate-mass X-ray binaries dominate the NS ULX population in M82- and MW-like Galaxies, respectively.

  3. Groups of Galaxies in AEGIS: The 200 ksec Chandra Extended X-ray Source catalogue

    CERN Document Server

    Jeltema, Tesla E; Laird, Elise S; Willmer, Christopher N A; Coil, Alison L; Cooper, Michael C; Davis, Marc; Nandra, Kirpal; Newman, Jeffrey A

    2009-01-01

    We present the discovery of seven X-ray emitting groups of galaxies selected as extended X-ray sources in the 200 ksec Chandra coverage of the All-wavelength Extended Groth Strip International Survey (AEGIS). In addition, we report on AGN activity associated to these systems. Using the DEEP2 Galaxy Redshift Survey coverage, we identify optical counterparts and determine velocity dispersions. In particular, we find three massive high-redshift groups at z>0.7, one of which is at z=1.13, the first X-ray detections of spectroscopically selected DEEP2 groups. We also present a first look at the the L_X-T, L_X-sigma, and sigma-T scaling relations for high-redshift massive groups. We find that the properties of these X-ray selected systems agree well with the scaling relations of similar systems at low redshift, although there are X-ray undetected groups in the DEEP2 catalogue with similar velocity dispersions. The other three X-ray groups with identified redshifts are associated with lower mass groups at z~0.07 and...

  4. Solving X-ray protein structures without a crystal: using X-ray Free Electron Laser, the fourth generation synchrotron light sources

    Institute of Scientific and Technical Information of China (English)

    Bo Huang

    2010-01-01

    @@ A synchrotron light source is a source of electromagnetic radiation artificially produced by specialized electron accelerators. Compared to the commonly used in-house X-ray sources, it is wavelength adjustable, much stronger and more focused. In the last two decades, synchrotron usage has become the mainstream for X-ray protein structure determination. Taking the advantage of micro-focus light beams of the third generation synchrotron, the size of a usable protein crystal for data collection decreases to micron level, which increases the rate of macromolecular structure determination to about 10 new protein data bank entries per day.

  5. Microfocus x-ray imaging of traceable pointlike {sup 22}Na sources for quality control

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, T.; Oda, K.; Sato, Y.; Ito, H.; Masuda, S.; Yamada, T.; Matsumoto, M.; Murayama, H.; Takei, H. [Allied Health Sciences, Kitasato University Kitasato 1-15-1, Minami-ku, Sagamihara-shi, Kanagawa 252-0373 (Japan); Positron Medical Center, Tokyo Metropolitan Institute of Gerontology Sakaecho 35-2, Itabashi-ku, Tokyo 173-0015 (Japan); Advanced Industrial Science and Technology (AIST) Central 2, Umezono 1-1-1, Tsukuba-shi, Ibaraki 305-8568 (Japan); Kanagawa Industrial Technology Center (KITC) Shimoimazumi 705-1, Ebina-shi, Kanagawa 243-0435 (Japan); Japan Radioisotope Association (JRIA) Komagome 2-28-45, Bunkyo-ku, Tokyo 113-8941 (Japan); Molecular Imaging Center, National Institute of Radiological Sciences Anagawa 4-9-1, Inage, Chiba 263-8555 (Japan); Graduate School of Medical Sciences, Kitasato University Kitasato 1-15-1, Minami-ku, Sagamihara-shi, Kanagawa 252-0373 (Japan)

    2012-07-15

    Purpose: The purpose of this study is to propose a microfocus x-ray imaging technique for observing the internal structure of small radioactive sources and evaluating geometrical errors quantitatively, and to apply this technique to traceable pointlike {sup 22}Na sources, which were designed for positron emission tomography calibration, for the purpose of quality control of the pointlike sources. Methods: A microfocus x-ray imaging system with a focus size of 0.001 mm was used to obtain projection x-ray images and x-ray CT images of five pointlike source samples, which were manufactured during 2009-2012. The obtained projection and tomographic images were used to observe the internal structure and evaluate geometrical errors quantitatively. Monte Carlo simulation was used to evaluate the effect of possible geometrical errors on the intensity and uniformity of 0.511 MeV annihilation photon pairs emitted from the sources. Results: Geometrical errors were evaluated with sufficient precision using projection x-ray images. CT images were used for observing the internal structure intuitively. As a result, four of the five examined samples were within the tolerance to maintain the total uncertainty below {+-}0.5%, given the source radioactivity; however, one sample was found to be defective. Conclusions: This quality control procedure is crucial and offers an important basis for using the pointlike {sup 22}Na source as a basic calibration tool. The microfocus x-ray imaging approach is a promising technique for visual and quantitative evaluation of the internal geometry of small radioactive sources.

  6. Tunable, all-optical quasi-monochromatic Thomson X-ray source

    CERN Document Server

    Khrennikov, K; Buck, A; Xu, J; Heigoldt, M; Veisz, L; Karsch, S

    2014-01-01

    Brilliant X-ray sources are of great interest for many research fields from biology via medicine to material research. The quest for a cost-effective, brilliant source with unprecedented temporal resolution has led to the recent realization of various high-intensity-laser-driven X-ray beam sources. Here we demonstrate the first all-laser-driven, energy-tunable and quasi-monochromatic X-ray source based on Thomson backscattering. This is a decisive step beyond previous results, where the emitted radiation exhibited an uncontrolled broad energy distribution. In the experiment, one part of the laser beam was used to drive a few-fs bunch of quasi-monoenergetic electrons from a Laser-Wakefield Accelerator (LWFA), while the remainder was scattered off the bunch in a near-counter-propagating geometry. When the electron energy was tuned from 10-50 MeV, narrow-bandwidth X-ray spectra peaking at 5-35keV were directly measured, limited in photon energy by the sensitivity curve of our X-ray detector. Due to the ultrashor...

  7. Discovery of Extremely Embedded X-ray Sources in the R Coronae Australis Star Forming Core

    CERN Document Server

    Hamaguchi, K; Petre, R; White, N E; Stelzer, B; Nedachi, K; Kobayashi, N; Tokunaga, A T; Hamaguchi, Kenji; Corcoran, Michael F.; Petre, Rob; White, Nicholas E.; Stelzer, Beate; Nedachi, Ko; Kobayashi, Naoto; Tokunaga, Alan T.

    2005-01-01

    With the XMM-Newton and Chandra observatories, we detected two extremely embedded X-ray sources in the R Corona Australis (R CrA) star forming core, near IRS 7. These sources, designated as XB and XA, have X-ray absorption columns of ~3e23 cm-2 equivalent to AV ~180 mag. They are associated with the VLA centimeter radio sources 10E and 10W, respectively. XA is the counterpart of the near-infrared source IRS 7, whereas XB has no K-band counterpart above 19.4 mag. This indicates that XB is younger than typical Class I protostars, probably a Class 0 protostar or in an intermediate phase between Class 0 and Class I. The X-ray luminosity of XB varied between 29X-ray brightness by a factor of two in 30 ksec during an XMM-Newton observation. The XMM-Newton spectra indicate emission from a hot plasma with kT ~3-4 keV and also show fluorescent emission from cold iron. Though the X-ray spectrum from XB is similar to flare ...

  8. On the origin of two unidentified radio/X-ray sources discovered with XMM-Newton

    Science.gov (United States)

    García, Federico; Combi, Jorge A.; Medina, María C.; Romero, Gustavo E.

    2015-12-01

    Aims: We aim at clarifying the nature of the emission of two spatially related unidentified X-ray sources detected with XMM-Newton telescope at intermediate-low Galactic latitude Methods: We use the imaging and spectral capabilities of XMM-Newton to study the X-ray properties of these two sources. In addition, we complement our study with radio data obtained at different frequencies to analyze a possible physical association between the sources. Results: Observations reveal a point-like source aligned with elongated diffuse emission. The X-ray spectra of these sources is best-fitted by an absorbed power law with photon index Γ ~ 1.7 for the point-like source and ~2.0 for the extended source. Both sources show nonthermal radio-continuum counterparts that might indicate a physical association. In addition, from the available data, we did not detect variability on the point-like source in several timescales. Two possible scenarios are analyzed: one Galactic and one extra-Galactic. First, based on HI line absorption, assuming a Galactic origin, we infer a distance upper bound of ≲2 kpc, which poses a constraint on the height over the Galactic plane of ≲200 pc and on the linear size of the system of ≲2.3 pc. In this case, the X-ray luminosities are ≳1032 erg s-1 and ≳7.5 × 1032 erg s-1, for the point-like and extended sources, respectively. Second, an extra-Galactic nature is discussed, where the point-like source might be the core of a radio galaxy and the extended source its lobe. In this case, we compare derived fluxes, spectral indices, and spatial correlation with those typical from the radio galaxy population, showing the feasibility of this alternative astrophysical scenario. Conclusions: From the available observational evidence, we suggest that the most promising scenario to explain the nature of these sources is a system consisting of a one-sided radio galaxy, where the point-like source is an active galactic nucleus and the extended source

  9. The Antennae Ultraluminous X-Ray Source, X-37, Is A Background Quasar

    CERN Document Server

    Clark, D M; Eikenberry, S S; Brandl, B R; Wilson, J C; Carson, J C; Henderson, C P; Hayward, T L; Barry, J; Ptak, A F; Colbert, E J M

    2005-01-01

    In this paper we report that a bright, X-ray source in the Antennae galaxies (NGC 4038/9), previously identified as an ultra-luminous X-ray source, is in fact a background quasar. We identify an isolated infrared and optical counterpart within 0.3+/-0.5 arcseconds the X-ray source X-37. After acquiring an optical spectrum of its counterpart, we use the narrow [OIII] and broad H_alpha emission lines to identify X-37 as a quasar at a redshift of z=0.26. Through a U, V, and K_s photometric analysis, we demonstrate that most of the observable light along this line of sight is from the quasar. We discuss the implications of this discovery and the importance of acquiring spectra for optical and IR counterparts to ULXs.

  10. The X-ray Correlation Spectroscopy instrument at the Linac Coherent Light Source

    Energy Technology Data Exchange (ETDEWEB)

    Alonso-Mori, Roberto; Caronna, Chiara; Chollet, Matthieu; Curtis, Robin; Damiani, Daniel S.; Defever, Jim; Feng, Yiping; Flath, Daniel L.; Glownia, James M. [Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States); Lee, Sooheyong [Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States); Hasylab at DESY, Notkestrasse 85, D-22607 Hamburg (Germany); Lemke, Henrik T.; Nelson, Silke; Bong, Eric; Sikorski, Marcin; Song, Sanghoon; Srinivasan, Venkat; Stefanescu, Daniel; Zhu, Diling; Robert, Aymeric, E-mail: aymeric@slac.stanford.edu [Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States)

    2015-04-14

    A description of the X-ray Correlation Spectroscopy instrument at the Linac Coherent Light Source is presented. Recent highlights illustrate the coherence properties of the source as well as some recent dynamics measurements and future directions. The X-ray Correlation Spectroscopy instrument is dedicated to the study of dynamics in condensed matter systems using the unique coherence properties of free-electron lasers. It covers a photon energy range of 4–25 keV. The intrinsic temporal characteristics of the Linac Coherent Light Source, in particular the 120 Hz repetition rate, allow for the investigation of slow dynamics (milliseconds) by means of X-ray photon correlation spectroscopy. Double-pulse schemes could probe dynamics on the picosecond timescale. A description of the instrument capabilities and recent achievements is presented.

  11. Non-Nuclear Hyper/Ultraluminous X-Ray Sources in the Starbursting Cartwheel Ring Galaxy

    CERN Document Server

    Gao, Y; Appleton, P N; Lucas, R A; Gao, Yu; Lucas, Ray A.

    2003-01-01

    We report the Chandra/ACIS-S detection of more than 20 ultraluminous X-ray sources (ULXs, L_{0.5-10 keV} >~ 3 x 10^{39} ergs/sec) in the Cartwheel collisional ring galaxy system, of which over a dozen are located in the outer active star-forming ring. A remarkable hyperluminous X-ray source (HLX, L_{0.5-10 keV} >~ 10^{41} ergs/sec assuming isotropic radiation), which dominates the X-ray emission from the Cartwheel ring, is located in the same segment of the ring as most ULXs. These powerful H/ULXs appear to be coincident with giant HII region complexes, young star clusters, and radio and mid-infrared hot-spots: all strong indicators of recent massive star formation. The X-ray spectra show that H/ULXs have similar properties as those of the {\\it most luminous} ULXs found in the nearest starbursts and galaxy mergers such as the Antennae galaxies and M82. The close association between the X-ray sources and the starbursting ring strongly suggests that the H/ULXs are intimately associated with the production and r...

  12. Generating Picosecond X-Ray Pulses with Beam Manipulation in Synchrotron Light Sources

    CERN Document Server

    Guo, Weiming; Harkay, Katherine C; Sajaev, Vadim; Yang Bing Xin

    2005-01-01

    The length of x-ray pulses generated by storage ring light sources is usually tens of picoseconds. For example, the value is 40 ps rms at the Advanced Photon Source (APS). Methods of x-ray pulse compression are of great interest at the APS. One possible method, per Zholents et al., is to tilt the electron bunch with deflecting rf cavities.* Alternately, we found that the electron bunch can develop a tilt after application of a vertical kick in the presence of nonzero chromaticity. After slicing, the x-ray pulse length is determined by the tilt angle and the vertical beam size. In principal, sub-picosecond pulses can be obtained at APS. To date we have observed 6 ps rms visible light pulses with a streak camera. Efforts are underway to attempt further compression of the x-ray pulse and to increase the brilliance. This method can be easily applied to any storage ring light sources to generate x-ray pulses up to two orders of magnitude shorter than the electron bunch length. In this paper, we will present the th...

  13. Flat Field Anomalies in an X-ray CCD Camera Measured Using a Manson X-ray Source (HTPD 08 paper)

    Energy Technology Data Exchange (ETDEWEB)

    Haugh, M; Schneider, M B

    2008-04-28

    The Static X-ray Imager (SXI) is a diagnostic used at the National Ignition Facility (NIF) to measure the position of the X-rays produced by lasers hitting a gold foil target. The intensity distribution taken by the SXI camera during a NIF shot is used to determine how accurately NIF can aim laser beams. This is critical to proper NIF operation. Imagers are located at the top and the bottom of the NIF target chamber. The CCD chip is an X-ray sensitive silicon sensor, with a large format array (2k x 2k), 24 {micro}m square pixels, and 15 {micro}m thick. A multi-anode Manson X-ray source, operating up to 10kV and 10W, was used to characterize and calibrate the imagers. The output beam is heavily filtered to narrow the spectral beam width, giving a typical resolution E/{Delta}E {approx} 10. The X-ray beam intensity was measured using an absolute photodiode that has accuracy better than 1% up to the Si K edge and better than 5% at higher energies. The X-ray beam provides full CCD illumination and is flat, within {+-}1% maximum to minimum. The spectral efficiency was measured at 10 energy bands ranging from 930 eV to 8470 eV. We observed an energy dependent pixel sensitivity variation that showed continuous change over a large portion of the CCD. The maximum sensitivity variation occurred at 8470 eV. The geometric pattern did not change at lower energies, but the maximum contrast decreased and was not observable below 4 keV. We were also able to observe debris, damage, and surface defects on the CCD chip. The Manson source is a powerful tool for characterizing the imaging errors of an X-ray CCD imager. These errors are quite different from those found in a visible CCD imager.

  14. Chandra Observations of the X-ray Point Source Population in NGC 4636

    CERN Document Server

    Posson-Brown, J; Forman, W; Donnelly, R H; Jones, C; Posson-Brown, Jennifer; Raychaudhury, Somak; Forman, William; Jones, Christine

    2006-01-01

    We present an analysis of the X-ray point source population in the nearby Virgo elliptical galaxy NGC 4636 from four Chandra X-ray observations. These ACIS observations, totaling ~210 ks, were taken over a three year period. Using a wavelet decomposition detection algorithm, we detect 336 individual point sources. For our analysis, we use a subset of the 245 detections with >10 cts (a limiting luminosity of approximately 1E37 erg/s in the 0.5-2 keV band, outside the 1.5' bright galaxy core). Of these sources, ~120 are likely members of the galaxy. We examine, for the first time, variability over a period of years for X-ray point sources in an elliptical galaxy. We present a luminosity function for the point sources in NGC 4636, fit by a power-law with gamma= -1.24 +/- 0.04, as well as a radial source density profile, hardness ratios for the sources, and lightcurves for bright sources which display short-term variability. We find an upper limit to the current X-ray luminosity of the historical supernova SN1939...

  15. What is the nature of the high energy X-ray sources in the galaxy?

    Science.gov (United States)

    Cuturilo, Sophie; Tomsick, John; Clavel, Maica; Lansbury, George B.

    2017-01-01

    Finding sources of high energy “hard” X-rays allow us to probe the most extreme conditions in the Universe. Such sources include accreting black holes and neutron stars, where we find the strongest gravitational and magnetic fields, as well as pulsars and supernova remnants, where particles are accelerated to produce the hard X-rays. Over the past decade, the INTEGRAL satellite ahs been discovering new high energy sources, and this has allowed us to understand the population of bright hard X-ray sources. Over the past few years, the NuSTAR satellite, with much better sensitivity than INTEGRAL, has been allowing us to find even more hard X-ray sources, and we will present results from studies of sources discovered in the NuSTAR serendipitous source survey. We analyzed seven different potential sources looking for counterparts using NuSTAR, Chandra and ground based optical/NIR observations. Of the seven, two have confirmed counterparts and five need either an optical/NIR detection or further spectroscopy.

  16. Electron-based EUV and ultrashort hard-x-ray sources

    Science.gov (United States)

    Egbert, A.; Mader, B.; Tkachenko, B.; Chichkov, B. N.

    2002-11-01

    A brief review of our progress in the realization of femtosecond laser-driven ultrashort hard-x-ray sources is given. New results on the development of electron-based compact EUV sources for "at-wavelength" metrology and next generation lithography are presented. AIP Conference Proceedings.

  17. Attenuation of super-soft X-ray sources by circumstellar material

    DEFF Research Database (Denmark)

    Nielsen, Mikkel; Gilfanov, Marat

    2015-01-01

    of the circumbinary material photo-ionised by the radiation of the central source. Our results show that the circumstellar mass-loss rates required for obcuration of super-soft X-ray sources is about an order of magnitude larger than those reported in earlier studies, for comparable model parameters. While this does...

  18. Measuring x-ray spectra of flash radiographic sources [PowerPoint

    Energy Technology Data Exchange (ETDEWEB)

    Gehring, Amanda Elizabeth [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Espy, Michelle A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Haines, Todd Joseph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mendez, Jacob [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Moir, David C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Sedillo, Robert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Shurter, Roger P. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Volegov, Petr Lvovich [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Webb, Timothy J [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-11-02

    The x-ray spectra of flash radiographic sources are difficult to measure. The sources measured were Radiographic Integrated Test Stand-6 (370 rad at 1 m; 50 ns pulse) and Dual Axis Radiographic Hydrodynamic Test Facility (DARHT) (550 rad at 1 m; 50 ns pulse). Features of the Compton spectrometer are described, and spectra are shown. Additional slides present data on instrumental calibration.

  19. Compact stacking of diode lasers for pulsed light sources of high brightness.

    Science.gov (United States)

    Alahautala, Taito; Lassila, Erkki; Hernberg, Rolf

    2004-07-20

    A compact stacking architecture for high-power diode-laser arrays is proposed and compared with traditional stacks. The objective of compact stacking is to achieve high brightness values without the use of microlenses. The calculated brightness for a compact stack is over 300 W mm(-2) sr(-1), which is approximately 40 times higher than that of a traditional stack made of similar laser emitters. Even higher brightness values of over 600 W mm(-2) sr(-1) were reached in practice. A laser head was manufactured in which the light from several compact laser stacks could be fiber coupled or the light could be transformed to a highly uniform beam.

  20. X-Rays Beware: The Deepest Chandra Catalogue of Point Sources in M31

    CERN Document Server

    Vulic, N; Barmby, P

    2016-01-01

    This study represents the most sensitive Chandra X-ray point source catalogue of M31. Using 133 publicly available Chandra ACIS-I/S observations totalling ~1 Ms, we detected 795 X-ray sources in the bulge, northeast, and southwest fields of M31, covering an area of approximately 0.6 deg$^{2}$, to a limiting unabsorbed 0.5-8.0 keV luminosity of $10^{34}$ erg/s. In the inner bulge, where exposure is approximately constant, X-ray fluxes represent average values because they were determined from many observations over a long period of time. Similarly, our catalogue is more complete in the bulge fields since monitoring allowed more transient sources to be detected. The catalogue was cross-correlated with a previous XMM-Newton catalogue of M31's $D_{25}$ isophote consisting of 1948 X-ray sources, with only 979 within the field of view of our survey. We found 387 (49%) of our Chandra sources (352 or 44% unique sources) matched to within 5 arcsec of 352 XMM-Newton sources. Combining this result with matching done to ...

  1. Integral field spectroscopy of the ultraluminous X-ray source Holmberg II X-1

    CERN Document Server

    Lehmann, I; Fabrika, S; Roth, M; Miyaji, T; Afanasiev, V; Sholukhova, O; Sánchez, S F; Greiner, J; Hasinger, G; Costantini, E; Surkov, A; Burenkov, A

    2004-01-01

    We present optical integral field observations of the H II region containing the ultraluminous X-ray source Holmberg II X-1. We confirm the existence of an X-ray ionized nebula as the counterpart of the source due to the detection of an extended He II (4686A) region (21 x 47 pc) at the Chandra ACIS-S position. An extended blue objects with a size of 11 x 14 pc is coincident with the X-ray/He II region, which could indicate either a young stellar complex or a cluster. We have derived an X-ray to optical luminosity ratio of Lx/Lb>170, and presumable it is Lx/Lb~300-400 using the recent HST ACS data. We find a complex velocity dispersion at the position of the ULX. In addition, there is a radial velocity variation in the X-ray ionized region found in the He II emission of +-50 km/s on spatial scales of 2-3 arcsec. We believe that the putative black hole not only ionizes the surrounding HII gas, but also perturbs it dynamically (via jets or the accretion disk wind). The spatial analysis of the public Chandra ACIS...

  2. Development of Compact Soft X-ray Source Based on Laser Undulator

    CERN Document Server

    Kuroda, Ryunosuke; Minamiguchi, S; Saitô, T; Ueyama, D; Washio, Masakazu

    2004-01-01

    A compact soft X-ray source is required in various research fields such as material and biological science. The laser undulator based on backward Compton scattering has been developed as a compact soft X-ray source for the biological observation at Waseda University. It is performed in a water window region (250eV - 500 eV) using the interaction between 1047 nm Nd:YLF laser and 4 MeV high quality electron beam generated from rf gun system. The range of energy in the water window region has K-shell absorption edges of Oxygen, Carbon and Nitrogen, which mainly constitute of living body. Since the absorption coefficient of water is much smaller than the protein’s coefficient in this range, a dehydration of the specimens is not necessary. As a preliminary experiment, about 300 eV X-ray generation was carried out. As next step, soft X-ray optics with zone plate was proposed for Soft X-ray microscopy. In this conference, we will report details and results of the experiment.

  3. At-wavelength metrology of x-ray optics at Diamond Light Source

    Science.gov (United States)

    Wang, Hongchang; Berujon, Sebastien; Sutter, John; Alcock, Simon G.; Sawhney, Kawal

    2014-09-01

    Modern, third-generation synchrotron radiation sources provide coherent and extremely bright beams of X-ray radiation. The successful exploitation of such beams depends to a significant extent on imperfections and misalignment of the optics employed on the beamlines. This issue becomes even more critical with the increasing use of active optics, and the desire to achieve diffraction-limited and coherence-preserving X-ray beams. In recent years, significant progress has been made to improve optic testing and optimization techniques, especially those using X-rays for so-called atwavelength metrology. These in-situ and at-wavelength metrology methods can be used not only to optimize the performance of X-ray optics, but also to correct and minimize the collective distortions of upstream beamline optics, including monochromators, and transmission windows. An overview of at-wavelength metrology techniques implemented at Diamond Light Source is presented, including grating interferometry and X-ray near-field speckle based techniques. Representative examples of the application of these techniques are also given, including in-situ and atwavelength calibration and optimization of: active, piezo bimorph mirrors; Kirkpatrick-Baez (KB) mirrors; and refractive optics such as compound refractive lenses.

  4. X-ray beam source from a Self-modulated laser wakefield accelerator

    Science.gov (United States)

    Lemos, Nuno; Albert, Felicie; Marsh, K. A.; Shaw, J. L.; King, P.; Patankar, S.; Ralph, J.; Pollock, B. B.; Martins, J. L.; Amorim, L. D.; Tsung, F. S.; Goyon, C.; Pak, A.; Moody, J. D.; Schumaker, W.; Fiuza, F.; Glenzer, S. H.; Hegelichand, B. M.; Saunders, A.; Flacone, R. W.; Joshi, C.

    2016-10-01

    To diagnose material properties under extreme conditions of temperature and pressure the development of a directional, small-divergence, small source size and short pulse duration x-ray source has become essential. In this work we explore through experiments and PIC simulations the betatron radiation generated in self-modulated laser-wakefield accelerators. The experiment was preformed at the Jupiter Laser Facility, LLNL where electrons with energies up to 200 MeV and Betatron x-rays with critical energies >10 keV were observed. OSIRIS 2D PIC simulations indicate that the x-ray critical energy directly scales with the a0 of the laser and can easily be increased to critical energies exceeding 50 keV using a laser with a0 of 3.

  5. Single particle imaging with soft x-rays at the Linac Coherent Light Source

    Science.gov (United States)

    Martin, Andrew V.; Andreasson, Jakob; Aquila, Andrew; Bajt, Saša; Barends, Thomas R. M.; Barthelmess, Miriam; Barty, Anton; Benner, W. Henry; Bostedt, Christoph; Bozek, John D.; Bucksbaum, Phillip; Caleman, Carl; Coppola, Nicola; DePonte, Daniel P.; Ekeberg, Tomas; Epp, Sascha W.; Erk, Benjamin; Farquar, George R.; Fleckenstein, Holger; Foucar, Lutz; Frank, Matthias; Gumprecht, Lars; Hampton, Christina Y.; Hantke, Max; Hartmann, Andreas; Hartmann, Elisabeth; Hartmann, Robert; Hau-Riege, Stephan P.; Hauser, Günther; Holl, Peter; Hoemke, André; Jönsson, Olof; Kassemeyer, Stephan; Kimmel, Nils; Kiskinova, Maya; Krasniqi, Faton; Krzywinski, Jacek; Liang, Mengning; Loh, Ne-Te Duane; Lomb, Lukas; Maia, Filipe R. N. C.; Marchesini, Stefano; Messerschmidt, Marc; Nass, Karol; Odic, Duško; Pedersoli, Emanuele; Reich, Christian; Rolles, Daniel; Rudek, Benedikt; Rudenko, Artem; Schmidt, Carlo; Schultz, Joachim; Seibert, M. Marvin; Shoeman, Robert L.; Sierra, Raymond G.; Soltau, Heike; Starodub, Dmitri; Steinbrener, Jan; Stellato, Francesco; Strüder, Lothar; Svenda, Martin; Tobias, Herbert; Ullrich, Joachim; Weidenspointner, Georg; Westphal, Daniel; White, Thomas A.; Williams, Garth; Hajdu, Janos; Schlichting, Ilme; Bogan, Michael J.; Chapman, Henry N.

    2011-06-01

    Results of coherent diffractive imaging experiments performed with soft X-rays (1-2 keV) at the Linac Coherent Light Source are presented. Both organic and inorganic nano-sized objects were injected into the XFEL beam as an aerosol focused with an aerodynamic lens. The high intensity and femtosecond duration of X-ray pulses produced by the Linac Coherent Light Source allow structural information to be recorded by X-ray diffraction before the particle is destroyed. Images were formed by using iterative methods to phase single shot diffraction patterns. Strategies for improving the reconstruction methods have been developed. This technique opens up exciting opportunities for biological imaging, allowing structure determination without freezing, staining or crystallization.

  6. A long-period, violently variable X-ray source in a young supernova remnant.

    Science.gov (United States)

    De Luca, A; Caraveo, P A; Mereghetti, S; Tiengo, A; Bignami, G F

    2006-08-11

    Observations with the Newton X-ray Multimirror Mission satellite show a strong periodic modulation at 6.67 +/- 0.03 hours of the x-ray source at the center of the 2000-year-old supernova remnant RCW 103. No fast pulsations are visible. If genetically tied to the supernova remnant, the source could either be an x-ray binary, composed of a compact object and a low-mass star in an eccentric orbit, or an isolated neutron star. In the latter case, the combination of its age and period would indicate that it is a peculiar magnetar, dramatically slowed down, possibly by a supernova debris disc. Both scenarios require nonstandard assumptions about the formation and evolution of compact objects in supernova explosions.

  7. Dual color x-rays from Thomson or Compton sources

    Science.gov (United States)

    Petrillo, V.; Bacci, A.; Curatolo, C.; Ferrario, M.; Maroli, C.; Rau, J. V.; Ronsivalle, C.; Serafini, L.; Vaccarezza, C.; Venturelli, M.

    2015-05-01

    We analyze the possibility of producing two color X or γ radiation by Thomson/Compton back-scattering between a high intensity laser pulse and a two-energy level electron beam, constituted by a couple of beamlets separated in time and/or energy obtained by a photoinjector with comb laser techniques and linac velocity bunching. The parameters of the Thomson source at SPARC_LAB have been simulated, proposing a set of values for a realistic experiments.

  8. Dual color x rays from Thomson or Compton sources

    Science.gov (United States)

    Petrillo, V.; Bacci, A.; Curatolo, C.; Ferrario, M.; Gatti, G.; Maroli, C.; Rau, J. V.; Ronsivalle, C.; Serafini, L.; Vaccarezza, C.; Venturelli, M.

    2014-02-01

    We analyze the possibility of producing two-color x or γ radiation by Thomson/Compton backscattering between a high intensity laser pulse and a two-energy level electron beam, constituted by a couple of beamlets separated in time and/or energy obtained by a photoinjector with comb laser techniques and linac velocity bunching. The parameters of the Thomson source at SPARC_LAB have been simulated, proposing a set of realistic experiments.

  9. Beam extraction dynamics at the space-charge-limit of the high brightness E-XFEL electron source at DESY-PITZ

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Ye; Gjonaj, Erion; Weiland, Thomas [TEMF, Technische Universitaet Darmstadt, Schlossgartenstrasse 8, 64289 Darmstadt (Germany)

    2015-07-01

    The physics of the photoemission, as one of the key issues for successful operation of linac based free-electron lasers like the European X-ray Free Electron Laser (E-XFEL) and the Free-electron Laser in Hamburg (FLASH), is playing an increasingly important role in the high brightness DESY-PITZ electron source. We study photoemission physics and discuss full three-dimensional numerical modeling of the electron bunch emission. The beam extraction dynamics at the photocathode has been investigated through the 3D fully electromagnetic (EM) Particle-in-Cell (PIC) solver of CST Particle Studio under the assumption of the photoemission source operating at or close to its space charge limit. PIC simulation results have shown good agreements with measurements on total emitted bunch charge for distinct experimental parameters. Further comparisons showed a general failure for the conventional Poisson solver based tracking algorithm to correctly predict the beam dynamics at the space charge limit. It is furthermore found, that fully EM PIC simulations are also consistent with a simple emission model based on the multidimensional Child-Langmuir law.

  10. A Compact Light Source: Design and Technical Feasibility Study of a Laser-Electron Storage Ring X-Ray Source

    Energy Technology Data Exchange (ETDEWEB)

    Loewen, R

    2004-02-02

    Thomson scattering infrared photons off energetic electrons provides a mechanism to produce hard X-rays desirable for applied sciences research. Using a small, modest energy (25MeV) electron storage ring together with a resonantly-driven optical storage cavity, a narrow spectrum of hard X-rays could be produced with the quality and monochromatic intensity approaching that of beamline sources at large synchrotron radiation laboratories. The general design of this X-ray source as well as its technical feasibility are presented. In particular, the requirements of optical pulse gain enhancement in an external cavity are described and experimentally demonstrated using a CW mode-locked laser.

  11. A Machine-learning approach to classification of X-ray sources

    Science.gov (United States)

    Hare, Jeremy; Kargaltsev, Oleg; Rangelov, Blagoy; Pavlov, George; Posselt, Bettina; Volkov, Igor

    2017-08-01

    Chandra and XMM-Newton X-ray observatories have serendipitously detected a large number of Galactic sources. Although their properties are automatically extracted and stored in catalogs, most of these sources remain unexplored. Classifying these sources can enable population studies on much larger scales and may also reveal new types of X-ray sources. For most of these sources the X-ray data alone are not enough to identify their nature, and multiwavelength data must be used. We developed a multiwavelength classification pipeline (MUWCLASS), which relies on supervised machine learning and a rich training dataset. We describe the training dataset, the pipeline and its testing, and will show/discuss how the code performs in different example environments, such as unidentified gamma-ray sources, supernova remnants, dwarf galaxies, stellar clusters, and the inner Galactic plane. We also discuss the application of this approach to the data from upcoming new X-ray observatories (e.g., eROSITA, Athena).

  12. The Chandra COSMOS Survey: III. Optical and Infrared Identification of X-ray Point Sources

    CERN Document Server

    Civano, F; Brusa, M; Comastri, A; Salvato, M; Zamorani, G; Aldcroft, T; Bongiorno, A; Capak, P; Cappelluti, N; Cisternas, M; Fiore, F; Fruscione, A; Hao, H; Kartaltepe, J; Koekemoer, A; Gilli, R; Impey, C D; Lanzuisi, G; Lusso, E; Mainieri, V; Miyaji, T; Lilly, S; Masters, D; Puccetti, S; Schawinski, K; Scoville, N Z; Silverman, J; Trump, J; Urry, M; Vignali, C; Wright, N J

    2012-01-01

    The Chandra COSMOS Survey (C-COSMOS) is a large, 1.8 Ms, Chandra program that has imaged the central 0.9 deg^2 of the COSMOS field down to limiting depths of 1.9 10^-16 erg cm^-2 s-1 in the 0.5-2 keV band, 7.3 10^-16 erg cm^-2 s^-1 in the 2-10 keV band, and 5.7 10^-16 erg cm^-2 s-1 in the 0.5-10 keV band. In this paper we report the i, K and 3.6micron identifications of the 1761 X-ray point sources. We use the likelihood ratio technique to derive the association of optical/infrared counterparts for 97% of the X-ray sources. For most of the remaining 3%, the presence of multiple counterparts or the faintness of the possible counterpart prevented a unique association. For only 10 X-ray sources we were not able to associate a counterpart, mostly due to the presence of a very bright field source close by. Only 2 sources are truly empty fields. Making use of the large number of X-ray sources, we update the "classic locus" of AGN and define a new locus containing 90% of the AGN in the survey with full band luminosi...

  13. High resolution stationary digital breast tomosynthesis using distributed carbon nanotube x-ray source array.

    Science.gov (United States)

    Qian, Xin; Tucker, Andrew; Gidcumb, Emily; Shan, Jing; Yang, Guang; Calderon-Colon, Xiomara; Sultana, Shabana; Lu, Jianping; Zhou, Otto; Spronk, Derrek; Sprenger, Frank; Zhang, Yiheng; Kennedy, Don; Farbizio, Tom; Jing, Zhenxue

    2012-04-01

    The purpose of this study is to investigate the feasibility of increasing the system spatial resolution and scanning speed of Hologic Selenia Dimensions digital breast tomosynthesis (DBT) scanner by replacing the rotating mammography x-ray tube with a specially designed carbon nanotube (CNT) x-ray source array, which generates all the projection images needed for tomosynthesis reconstruction by electronically activating individual x-ray sources without any mechanical motion. The stationary digital breast tomosynthesis (s-DBT) design aims to (i) increase the system spatial resolution by eliminating image blurring due to x-ray tube motion and (ii) reduce the scanning time. Low spatial resolution and long scanning time are the two main technical limitations of current DBT technology. A CNT x-ray source array was designed and evaluated against a set of targeted system performance parameters. Simulations were performed to determine the maximum anode heat load at the desired focal spot size and to design the electron focusing optics. Field emission current from CNT cathode was measured for an extended period of time to determine the stable life time of CNT cathode for an expected clinical operation scenario. The source array was manufactured, tested, and integrated with a Selenia scanner. An electronic control unit was developed to interface the source array with the detection system and to scan and regulate x-ray beams. The performance of the s-DBT system was evaluated using physical phantoms. The spatially distributed CNT x-ray source array comprised 31 individually addressable x-ray sources covering a 30 angular span with 1 pitch and an isotropic focal spot size of 0.6 mm at full width at half-maximum. Stable operation at 28 kV(peak) anode voltage and 38 mA tube current was demonstrated with extended lifetime and good source-to-source consistency. For the standard imaging protocol of 15 views over 14, 100 mAs dose, and 2 × 2 detector binning, the projection

  14. The 172 ks Chandra Exposure of the LALA Bootes Field: X-Ray Source Catalog

    Science.gov (United States)

    Wang, J. X.; Malhotra, S.; Rhoads, J. E.; Brown, M. J. I.; Dey, A.; Heckman, T. M.; Jannuzi, B. T.; Norman, C. A.; Tiede, G. P.; Tozzi, P.

    2004-01-01

    We present an analysis of a deep, 172 ks Chandra observation of the Large Area Lyman Alpha survey (LALA) Bootes field, obtained with the Advanced CCD Imaging Spectrometer (ACIS-I) on board the Chandra X-Ray Observatory. This is one of the deepest Chandra images of the extragalactic sky; only the 2 Ms Chandra Deep Field North (CDF-N) and 1 Ms Chandra Deep Field South (CDF-S) are substantially deeper. In this paper we present the X-ray source catalog obtained from this image, along with an analysis of source counts and optical identifications. The X-ray image is composed of two individual observations obtained in 2002 and reaches 0.5-2.0 and 2.0-10.0 keV flux limits of 1.5×10-16 and 1.0×10-15 ergs cm-2 s-1, respectively, for point sources near the aim point. A total of 168 X-ray sources were detected: 160 in the 0.5-7.0 keV band, 132 in the 0.5-2.0 keV band, and 111 in the 2.0-7.0 keV band. The X-ray source counts were derived and compared with those from other Chandra deep surveys; the hard X-ray source density of the LALA Bootes field is 33% higher than that of CDF-S at the flux level of 2.0×10-15 ergs cm-2 s-1, confirming the field-to-field variances of the hard-band source counts reported by previous studies. The deep exposure resolves >~72% of the 2.0-10.0 keV X-ray background. Our primary optical data are R-band imaging from the NOAO Deep Wide-Field Survey (NDWFS), with a limiting magnitude of R=25.7 (Vega, 3 σ, and 4" diameter aperture). We have found optical counterparts for 152 of the 168 Chandra sources (90%); 144 of these are detected in the R-band image, and eight have optical counterparts in other bands (either BW, V, I, or z'). Among the R-band nondetected sources, not more than 11 of them can possibly be at z>5, based on the hardness ratios of their X-ray emission and nondetections in bluer bands (BW, V). The majority (~76%) of the X-ray sources are found to have log(fX/fR) within 0.0+/-1 these are believed to be AGNs. Most of the X-ray

  15. Soft x-ray imaging with incoherent sources

    Science.gov (United States)

    Wachulak, P.; Torrisi, A.; Ayele, M.; Bartnik, A.; Czwartos, J.; Wegrzyński, Ł.; Fok, T.; Parkman, T.; Vondrová, Š.; Turnová, J.; Odstrcil, M.; Fiedorowicz, H.

    2017-05-01

    In this work we present experimental, compact desk-top SXR microscope, the EUV microscope which is at this stage a technology demonstrator, and finally, the SXR contact microscope. The systems are based on laser-plasma EUV and SXR sources, employing a double stream gas puff target. The EUV and SXR full field microscopes, operating at 13.8 nm and 2.88 nm wavelengths, respectively, are capable of imaging nanostructures with a sub-50 nm spatial resolution with relatively short (seconds) exposure times. The SXR contact microscope operates in the "water-window" spectral range, to produce an imprint of the internal structure of the sample in a thin layer of SXR light sensitive photoresist. Applications of such desk-top EUV and SXR microscopes for studies of variety of different samples - test objects for resolution assessment and other objects such as carbon membranes, DNA plasmid samples, organic and inorganic thin layers, diatoms, algae and carcinoma cells, are also presented. Details about the sources, the microscopes as well as the imaging results for various objects will be presented and discussed. The development of such compact imaging systems may be important to the new research related to biological, material science and nanotechnology applications.

  16. Location of the Norma transient with the HEAO 1 scanning modulation collimator. [X ray source in Norma Constellation

    Science.gov (United States)

    Fabbiano, G.; Gursky, H.; Schwartz, D. A.; Schwarz, J.; Bradt, H. V.; Doxsey, R. E.

    1978-01-01

    A precise position has been obtained for an X-ray transient source in Norma. The location uncertainty includes a variable star previously suggested to be the optical counterpart. This transient is associated with the steady X-ray source MX 1608-52 and probably with an X-ray burst source. A binary system containing a low-mass primary and a neutron-star or black-hole secondary of a few solar masses is consistent with the observations.

  17. Location of the Norma transient with the HEAO 1 scanning modulation collimator. [X ray source in Norma Constellation

    Science.gov (United States)

    Fabbiano, G.; Gursky, H.; Schwartz, D. A.; Schwarz, J.; Bradt, H. V.; Doxsey, R. E.

    1978-01-01

    A precise position has been obtained for an X-ray transient source in Norma. The location uncertainty includes a variable star previously suggested to be the optical counterpart. This transient is associated with the steady X-ray source MX 1608-52 and probably with an X-ray burst source. A binary system containing a low-mass primary and a neutron-star or black-hole secondary of a few solar masses is consistent with the observations.

  18. Next Generation High Brightness Electron Beams From Ultra-High Field Cryogenic Radiofrequency Photocathode Sources

    CERN Document Server

    Rosenzweig, J B; Dolgashev, V; Emma, C; Fukusawa, A; Li, R; Limborg, C; Maxson, J; Musumeci, P; Nause, A; Pakter, R; Pompili, R; Roussel, R; Spataro, B; Tantawi, S

    2016-01-01

    Recent studies of the performance of radio-frequency (RF) copper structures operated at cryogenic temperatures have shown a dramatic increase in the maximum surface electric field that may be reached. We propose to utilize this development to enable a new generation of photoinjectors operated at cryogenic temperatures that may attain, through enhancement of the launch field at the photocathode by a factor of four, well over an order of magnitude increase in peak electron beam brightness. We present detailed studies of the beam dynamics associated with such a system, concentrating on an emittance-compensated S-band photoinjector that may directly substitute that of the LCLS X-ray free-electron laser. We show in this case that the increase in brightness leads directly to a factor of two reduction in gain length, with attendant increase in X-ray radiative efficiency. Extreme low emittance scenarios obtained at low operating charge, appropriate for dramatically pushing performance limits of ultrafast electron dif...

  19. UV-Visible Absorption Spectroscopy Enhanced X-ray Crystallography at Synchrotron and X-ray Free Electron Laser Sources.

    Science.gov (United States)

    Cohen, Aina E; Doukov, Tzanko; Soltis, Michael S

    2016-01-01

    This review describes the use of single crystal UV-Visible Absorption micro-Spectrophotometry (UV-Vis AS) to enhance the design and execution of X-ray crystallography experiments for structural investigations of reaction intermediates of redox active and photosensitive proteins. Considerations for UV-Vis AS measurements at the synchrotron and associated instrumentation are described. UV-Vis AS is useful to verify the intermediate state of an enzyme and to monitor the progression of reactions within crystals. Radiation induced redox changes within protein crystals may be monitored to devise effective diffraction data collection strategies. An overview of the specific effects of radiation damage on macromolecular crystals is presented along with data collection strategies that minimize these effects by combining data from multiple crystals used at the synchrotron and with the X-ray free electron laser.

  20. X-ray emission from the giant molecular clouds in the Galactic Center region and the discovery of new X-ray sources

    CERN Document Server

    Sidoli, L; Treves, A; Parmar, A N; Turolla, R; Favata, F

    2001-01-01

    We report the results of X-ray (2-10 keV) observations of the giant molecular clouds SgrB, SgrC and SgrD in the Galactic Center region, together with the discovery of the point-like source SAXJ1748.2-2808. The data have been obtained with the MECS instrument on the BeppoSAX satellite. The core of SgrB2 has an X-ray luminosity of 6x10^34 erg/s and its spectrum is characterized by a strong Fe emission line at 6.5 keV with an equivalent width of 2 keV. Faint diffuse X-ray emission is detected from SgrC and from the SNR G1.05-0.15 (SgrD). A new, unresolved source with a strong Fe line has been discovered in the SgrD region. This source, SAXJ1748.2-2808, is probably associated with a SiO and OH maser source at the Galactic Center distance. If so, its luminosity is 10^34 erg/s. We propose that the X-ray emission from SAX J1748.2-2808 is produced either by protostars or by a giant molecular cloud core. Emission from sources similar to SAX J1748.2-2808 could have an impact on the expected contribution on the observed...

  1. Resolved atomic lines reveal outflows in two ultraluminous X-ray sources

    CERN Document Server

    Pinto, Ciro; Fabian, Andrew C

    2016-01-01

    Ultraluminous X-ray sources are extragalactic, off-nucleus, point sources in galaxies with an X-ray luminosity above 3x10^39 erg/s, thought to be powered by accretion onto a compact object. Possible explanations include accretion onto neutron stars with strong magnetic fields, stellar-mass black holes ( 5 sigma, and blueshifted (~0.2c) absorption lines (5 sigma) in the high-resolution X-ray spectrum of the ultraluminous X-ray source NGC 1313 X-1. In a similar source, NGC 5408 X-1, we also detect emission lines at rest and blueshifted absorption. The blueshifted absorption lines must occur in a fast outflowing gas, whereas the emission lines originate in slow-moving gas around the source. We conclude that the compact object is surrounded by powerful winds with an outflow velocity of about 0.2c as predicted by models of accreting supermassive black holes and hyper-accreting stellar mass black holes.

  2. Discrete X-Ray Source Populations and Star-Formation History in Nearby Galaxies

    Science.gov (United States)

    Zezas, Andreas

    2004-01-01

    This program aims in understanding the connection between the discrete X-ray source populations observed in nearby galaxies and the history of star-formation in these galaxies. The ultimate goal is to use this knowledge in order to constrain X-ray binary evolution channels. For this reason although the program is primarily observational it has a significant modeling component. During the first year of this study we focused on the definition of a pilot sample of galaxies with well know star-formation histories. A small part of this sample has already been observed and we performed initial analysis of the data. However, the majority of the objects in our sample either have not been observed at all, or the detection limit of the existing observations is not low enough to probe the bulk of their young X-ray binary populations. For this reason we successfully proposed for additional Chandra observations of three targets in Cycle-5. These observations are currently being performed. The analysis of the (limited) archival data for this sample indicated that the X-ray luminosity functions (XLF) of the discrete sources in these galaxies may not have the same shape as is widely suggested. However, any solid conclusions are hampered by the small number of detected sources. For this reason during the second year of this study, we will try to extend the sample in order to include more objects in each evolutionary stage. In addition we are completing the analysis of the Chandra monitoring observations of the Antennae galaxies. The results from this work, apart from important clues on the nature of the most luminous sources (Ultra-luminous X-ray sources; ULXs) provide evidence that source spectral and/or temporal variability does not significantly affect the shape of their X-ray luminosity functions. This is particularly important for comparisons between the XLFs of different galaxies and comparisons with predictions from theoretical models. Results from this work have been

  3. The missing link between ultraluminous X-ray sources and metallicity

    CERN Document Server

    Mapelli, M

    2013-01-01

    The nature of ultraluminous X-ray sources (ULXs) is still debated. Recent studies show that metal-poor massive stars can collapse into massive stellar black holes (MSBHs), that is black holes with mass > 25 Msun. Such MSBHs are sufficiently massive to explain most ULXs without requiring substantial violations of the Eddington limit. The recent finding of an anti-correlation between metallicity of the environment and number of ULXs per galaxy supports this hypothesis. We present the results of recent N-body simulations, including metallicity dependent stellar evolution, and we discuss the main pathways to produce X-ray binaries powered by MSBHs.

  4. Scanning soft X-ray spectromicroscopy at the Pohang Light Source: commissioning results

    CERN Document Server

    Shin, H J

    2001-01-01

    A scanning spectromicroscopy facility has been installed at the undulator radiation beamline at the Pohang Light Source. The spectromicroscopy is operational in both the scanning transmission X-ray microscopy (STXM) and the scanning photoelectron microscopy (SPEM) modes. Currently, the measured X-ray spot size on the sample is about 0.4 mu m. The effective photon energy range of the STXM is 250-1000 eV and that of the SPEM is 400-1000 eV. The performance of the facility is presented in this report.

  5. Carbon nanotubes as electron source in an x-ray tube

    OpenAIRE

    H., Sugie; Masaki, Tanemura; V., Filip; K., Iwata; K., Takahashi; F., Okuyama

    2001-01-01

    Field emitters comprised of aligned carbon nanotubes are shown to be promising as a primary electron source in an x-ray tube working in a nonultrahigh vacuum ambience. At a pressure of 2×10-7Torr, the nanotube emitters continue to emit electrons for more than 1 h, and yield better resolved x-ray images than do thermionic emitters, independently of whether the sample is biological or nonbiological. The near-uniformity in energy distribution of electrons emitted from carbon nanotubes might be r...

  6. Filtered x-ray diode diagnostics fielded on the Z-accelerator for source power measurements

    Energy Technology Data Exchange (ETDEWEB)

    Chandler, G.A.; Deeney, C.; Cuneo, M. [and others

    1998-06-02

    Filtered x-ray diode, (XRD), detectors are used as primary radiation flux diagnostics on Sandia`s Z-accelerator, which generates nominally a 200 TW, 2 MJ, x-ray pulse. Given such flux levels and XRD sensitivities the detectors are being fielded 23 meters from the source. The standard diagnostic setup and sensitivities are discussed. Vitreous carbon photocathodes are being used to reduce the effect of hydrocarbon contamination present in the Z-machine vacuum system. Nevertheless pre- and post-calibration data taken indicate spectrally dependent changes in the sensitivity of these detectors by up to factors up to 2 or 3.

  7. Condenser for Koehler-like illumination in transmission x-ray microscopes at undulator sources

    Science.gov (United States)

    Vogt, Ulrich; Lindblom, Magnus; Charalambous, Pambos; Kaulich, Burkhard; Wilhein, Thomas

    2006-05-01

    We report on a novel condenser for full-field transmission x-ray microscopes that use synchrotron radiation from an undulator source. The condenser produces a Koehler-like homogeneous intensity distribution in the sample plane and eliminates object illumination problems connected with the high degree of spatial coherence in an undulator beam. The optic consists of a large number of small linear diffraction gratings and is therefore relatively easy to manufacture. First imaging experiments with a prototype condenser were successfully performed with the Twinmic x-ray microscope at the Elettra synchrotron facility in Italy.

  8. Condenser for Koehler-like illumination in transmission x-ray microscopes at undulator sources.

    Science.gov (United States)

    Vogt, Ulrich; Lindblom, Magnus; Charalambous, Pambos; Kaulich, Burkhard; Wilhein, Thomas

    2006-05-15

    We report on a novel condenser for full-field transmission x-ray microscopes that use synchrotron radiation from an undulator source. The condenser produces a Koehler-like homogeneous intensity distribution in the sample plane and eliminates object illumination problems connected with the high degree of spatial coherence in an undulator beam. The optic consists of a large number of small linear diffraction gratings and is therefore relatively easy to manufacture. First imaging experiments with a prototype condenser were successfully performed with the Twinmic x-ray microscope at the Elettra synchrotron facility in Italy.

  9. Diamond planar refractive lenses for third- and fourth-generation X-ray sources.

    Science.gov (United States)

    Nöhammer, Bernd; Hoszowska, Joanna; Freund, Andreas K; David, Christian

    2003-03-01

    The fabrication and testing of planar refractive hard X-ray lenses made from bulk CVD diamond substrates is reported. The lens structures were generated by electron-beam lithography and transferred by reactive-ion etching into the diamond. Various lens designs were fabricated and tested at 12.4 and 17.5 keV photon energy. Efficiencies of up to 71% and gains of up to 26 were achieved. A line focus of 3.2 micro m (FWHM) was measured. These lenses should be able to withstand the extreme flux densities expected at the planned fourth-generation X-ray sources.

  10. Discrete X-Ray Source Populations and Star Formation History in Nearby Galaxies

    Science.gov (United States)

    Zezas, Andreas; Hasan, Hashima (Technical Monitor)

    2005-01-01

    This program aims in understanding the connection between the discrete X-ray source populations observed in nearby galaxies and the history of star-formation in these galaxies. The ultimate goal is to use this knowledge in order to constrain X-ray binary evolution channels. For this reason although the program is primarily observational it has a significant modeling component. During the second year of this study we focused on detailed studies of the Antennae galaxies and the Small Magellanic Cloud (SMC). We also performed the initial analysis of the 5 galaxies forming a starburst-age sequence.

  11. Linear parabolic single-crystal diamond refractive lenses for synchrotron X-ray sources.

    Science.gov (United States)

    Terentyev, Sergey; Polikarpov, Maxim; Snigireva, Irina; Di Michiel, Marco; Zholudev, Sergey; Yunkin, Vyacheslav; Kuznetsov, Sergey; Blank, Vladimir; Snigirev, Anatoly

    2017-01-01

    Linear parabolic diamond refractive lenses are presented, designed to withstand high thermal and radiation loads coming from upgraded accelerator X-ray sources. Lenses were manufactured by picosecond laser treatment of a high-quality single-crystal synthetic diamond. Twelve lenses with radius of curvature at parabola apex R = 200 µm, geometrical aperture A = 900 µm and length L = 1.5 mm were stacked as a compound refractive lens and tested at the ESRF ID06 beamline. A focal spot of size 2.2 µm and a gain of 20 were measured at 8 keV. The lens profile and surface quality were estimated by grating interferometry and X-ray radiography. In addition, the influence of X-ray glitches on the focusing properties of the compound refractive lens were studied.

  12. Compact tunable Compton x-ray source from laser-plasma accelerator and plasma mirror

    CERN Document Server

    Tsai, Hai-En; Shaw, Joseph; Li, Zhengyan; Arefiev, Alexey V; Zhang, Xi; Zgadzaj, Rafal; Henderson, Watson; Khudik, V; Shvets, G; Downer, M C

    2014-01-01

    We present results of the first tunable Compton backscattering (CBS) x-ray source that is based on the easily aligned combination of a laser-plasma accelerator (LPA) and a plasma mirror (PM). The LPA is driven in the blowout regime by 30 TW, 30 fs laser pulses, and produces high-quality, tunable, quasi-monoenergetic electron beams. A thin plastic film near the gas jet exit efficiently retro-reflects the LPA driving pulse with relativistic intensity into oncoming electrons to produce $2\\times10^{7}$ CBS x-ray photons per shot with 10-20 mrad angular divergence and 50 % (FWHM) energy spread without detectable bremsstrahlung background. The x-ray central energy is tuned from 75 KeV to 200 KeV by tuning the LPA e-beam central energy. Particle-in-cell simulations of the LPA, the drive pulse/PM interaction and CBS agree well with measurements.

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

    CERN Document Server

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

    2010-01-01

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

  14. Free-fall accretion and emitting caustics in wind-fed X-ray sources

    Science.gov (United States)

    Illarionov, Andrei F.; Beloborodov, Andrei M.

    2001-05-01

    In wind-fed X-ray binaries the accreting matter is Compton-cooled and falls freely on to the compact object. The matter has a modest angular momentum l and accretion is quasi-spherical at large distances from the compact object. Initially small non-radial velocities grow in the converging supersonic flow and become substantial in the vicinity of the accretor. The streamlines with l>(GMR*)1/2 (where M and R* are the mass and radius of the compact object) intersect outside R* and form a two-dimensional caustic which emits X-rays. The streamlines with low angular momentum, lorbital phase of the binary. The accretor then appears as a `Moon-like' X-ray source.

  15. Ultraluminous X-ray sources as super-Eddington accretion disks

    CERN Document Server

    Fabrika, Sergei; Atapin, Kirill

    2016-01-01

    The origin of Ultraluminous X-ray sources (ULXs) in external galaxies whose X-ray luminosities exceed those of the brightest black holes in our Galaxy by hundreds and thousands of times is mysterious. The most popular models for the ULXs involve either intermediate mass black holes (IMBHs) or stellar-mass black holes accreting at super-Eddington rates. Here we review the ULX properties, their X-ray spectra indicate a presence of hot winds in their accretion disks supposing the supercritical accretion. However, the strongest evidences come from optical spectroscopy. The spectra of the ULX counterparts are very similar to that of SS 433, the only known supercritical accretor in our Galaxy.

  16. ESO 103-G35 - A new Seyfert galaxy and possible X-ray source

    Science.gov (United States)

    Phillips, M. M.; Feldman, F. R.; Marshall, F. E.; Wamsteker, W.

    1979-01-01

    By means of an objective prism plate, two emission-line galaxies have been identified within the 0.7-sq deg HEAO-A2 error box for the X-ray source H1834-653. Optical spectrophotometric observations are reported for both objects as well as the galaxy NGC 6684, which also lies near the position of H1834-653. These data show that one of the emission-line galaxies, ESO 103-G35, is a Seyfert galaxy with a high-excitation forbidden-line spectrum and weak broad emission wings at H-alpha. Further measurements of this galaxy reveal an infrared excess at wavelengths longer than 2.2 microns. The H-alpha luminosity of ESO 103-G35 is consistent with the X-ray luminosity estimated from the HEAO-A2 data, thus strengthening the likelihood of association of this galaxy with the X-ray emission.

  17. ESO 103-G35 - A new Seyfert galaxy and possible X-ray source

    Science.gov (United States)

    Phillips, M. M.; Feldman, F. R.; Marshall, F. E.; Wamsteker, W.

    1979-01-01

    By means of an objective prism plate, two emission-line galaxies have been identified within the 0.7-sq deg HEAO-A2 error box for the X-ray source H1834-653. Optical spectrophotometric observations are reported for both objects as well as the galaxy NGC 6684, which also lies near the position of H1834-653. These data show that one of the emission-line galaxies, ESO 103-G35, is a Seyfert galaxy with a high-excitation forbidden-line spectrum and weak broad emission wings at H-alpha. Further measurements of this galaxy reveal an infrared excess at wavelengths longer than 2.2 microns. The H-alpha luminosity of ESO 103-G35 is consistent with the X-ray luminosity estimated from the HEAO-A2 data, thus strengthening the likelihood of association of this galaxy with the X-ray emission.

  18. An injector for the proposed Berkeley Ultrafast X-Ray Light Source

    Energy Technology Data Exchange (ETDEWEB)

    Lidia, Steven; Corlett, John; Pusina, Jan; Staples, John; Zholents, Alexander

    2003-05-19

    Berkeley Lab has proposed to build a recirculating linac based X-ray source for ultra-fast dynamic studies [1]. This machine requires a flat electron beam with a small vertical emittance and large x/y emittance ratio to allow for compression of spontaneous undulator emission of soft and hard x-ray pulses, and a low-emittance, round electron beam for coherent emission of soft x-rays via the FEL process based on cascaded harmonic generation [2]. We propose an injector system consisting of two high gradient high repetition rate photo cathode guns [3] (one for each application), an {approx}120 MeV super conducting linear accelerator, a 3rd harmonic cavity for linearization of the longitudinal phase space, and a bunch compressor. We present details of the design and the results of particle tracking studies using several computer codes.

  19. The Lack of Very Ultraluminous X-ray Sources in Early-type Galaxies

    CERN Document Server

    Irwin, J A; Athey, A E; Irwin, Jimmy A.; Bregman, Joel N.; Athey, Alex E.

    2004-01-01

    We have searched for ultraluminous X-ray sources (ULXs) in a sample of 28 elliptical and S0 galaxies observed with Chandra. We find that the number of X-ray sources detected at a flux level that would correspond to a 0.3-10 keV X-ray luminosity of ~2 x 10^39 ergs/s or greater (for which we have used the designation very ultraluminous X-ray sources; VULXs) at the distance of each galaxy is equal to the number of expected foreground/background objects. In addition, the VULXs are uniformly distributed over the Chandra field of view rather than distributed like the optical light of the galaxies, strengthening the argument that the high flux sources are unassociated with the galaxies. We have also taken the VULX candidate list of Colbert and Ptak and determined the spatial distribution of VULXs in early-type galaxies and late-type galaxies separately. While the spiral galaxy VULXs are clearly concentrated toward the centers of the galaxies, the early-type galaxy VULXs are distributed randomly over the ROSAT HRI fi...

  20. Chandra observation of an ultraluminous X-ray source from the Galaxy NGC 12911

    CERN Document Server

    Luna, Juan C

    2009-01-01

    I report the analysis of an ultraluminous X-ray source (ULX) located in the galaxy NGC 1291. This X-ray point source is denominated IXO6 in the Catalog of Candidate IXO (Colbert & Ptak). An Intermediate-luminosity X-ray Object (IXO) is defined as an off-nuclear, compact object with luminosity Lx [2-10keV] >= 1039 erg s-1. The cutoff Lx is defined as a value greater than the Eddington luminosity of a 1.4 Mo black hole (10 38.3 erg s-1). IXO is an early denomination of what is call now a ULX point source. The Catalog was derived from a ROSAT survey and represents 87 IXOS in 54 galaxies. IXO6 was selected because of being positioned in the outer disk of the galaxy, with no near X-ray source neighbors. The study of this ULX pretends to confirm certain assumptions related to this class of objects (Roberts et al.)

  1. Observational Evidence for Intermediate-Mass Black Holes in Ultra-luminous X-ray Sources

    CERN Document Server

    Colbert, E J M

    2004-01-01

    Evidence is mounting that some Ultra-luminous X-ray sources (ULXs) may contain accreting intermediate-mass black holes (IMBHs). We review the current observational evidence for IMBH-ULXs. While low-luminosity ULXs with L_X ~ 10^40 ergs, we suggest that this class of ULXs is generally powered by accreting IMBHs.

  2. The Chandra COSMOS-Legacy survey: Source X-ray spectral properties

    CERN Document Server

    Marchesi, S; Civano, F; Iwasawa, K; Suh, H; Comastri, A; Zamorani, G; Allevato, V; Griffiths, R; Miyaji, T; Ranalli, P; Salvato, M; Schawinski, K; Silverman, J; Treister, E; Urry, C M; Vignali, C

    2016-01-01

    We present the X-ray spectral analysis of the 1855 extragalactic sources in the Chandra COSMOS-Legacy survey catalog having more than 30 net counts in the 0.5-7 keV band. 38% of the sources are optically classified Type 1 active galactic nuclei (AGN), 60% are Type 2 AGN and 2% are passive, low-redshift galaxies. We study the distribution of AGN photon index and of the intrinsic absorption N(H,z) based on the sources optical classification: Type 1 have a slightly steeper mean photon index than Type 2 AGN, which on the other hand have average intrinsic absorption ~3 times higher than Type 1 AGN. We find that ~15% of Type 1 AGN have N(H,z)>1E22 cm^(-2), i.e., are obscured according to the X-ray spectral fitting; the vast majority of these sources have L(2-10keV)>$1E44 erg/s. The existence of these objects suggests that optical and X-ray obscuration can be caused by different phenomena, the X-ray obscuration being for example caused by dust-free material surrounding the inner part of the nuclei. ~18% of Type 2 AG...

  3. Simulating the sensitivity to stellar point sources of Chandra X-ray observations

    CERN Document Server

    Wright, Nicholas J; Guarcello, Mario G; Kashyap, Vinay L; Zezas, Andreas

    2015-01-01

    The Chandra Cygnus OB2 Legacy Survey is a wide and deep X-ray survey of the nearby and massive Cygnus OB2 association. The survey has detected ~8,000 X-ray sources, the majority of which are pre-main sequence X-ray emitting young stars in the association itself. To facilitate quantitative scientific studies of these sources as well as the underlying OB association it is important to understand the sensitivity of the observations and the level of completeness the observations have obtained. Here we describe the use of a hierarchical Monte Carlo simulation to achieve this goal by combining the empirical properties of the observations, analytic estimates of the source verification process, and an extensive set of source detection simulations. We find that our survey reaches a 90% completeness level for a pre-main-sequence population at the distance of Cyg OB2 at an X-ray luminosity of 4 x 10^30 ergs/s and a stellar mass of 1.3 Msun for a randomly distributed population. For a spatially clustered population such ...

  4. Three transient X-ray sources during the INTEGRAL revolution 1710

    Science.gov (United States)

    Fiocchi, M.; Bazzano, A.; Bird, A. J.; Charles, Phil; Chenevez, J.; Ubertini, P.

    2016-08-01

    During recent INTEGRAL observations of the Musca and Norma regions (revolutions 1710) performed between 2016-08-05 16:00:36 UTC and 2016-08-07 21:02:14 UTC a renewed activity from the following transient X-ray sources has been detected.

  5. Monte Carlo Study on Focus Properties of Portable Ultrabright Microfocus X-Ray Sources

    Institute of Scientific and Technical Information of China (English)

    WANG Kai-Ge; WANG Lei; LIU Wen-Qing; NIU Han-Ben

    2006-01-01

    @@ The construct and electrode potential of emitting systems are very important for the portable ultrahigh brightness microfocus x-ray sources. The ratio of Dw/H (Dw is the diameter of Wehnelt grid aperture and H is the setting height of the cathode) and the grid bias are determinative parameters for the emission current and focus properties of an electron beam.

  6. Initial lattice studies for the Berkeley Femtosecond X-ray Light Source

    Science.gov (United States)

    Zholents, A.; Reichel, I.; Robin, D.; Tanabe, J.; Wan, W.

    2002-05-01

    We present lattice studies for a proposed femtosecond synchrotron radiation X-ray source based on a recirculating accelerator. After a general description, we cover specific aspects of the lattice that are relevant to this type of machine and show preliminary results of particle tracking and briefly describe a new code developed for a comprehensive particle tracking in recirculating accelerators.

  7. Hard X-ray and microwave sources located around the apex of a solar flare loop

    Science.gov (United States)

    Masuda, S.; Shimojo, M.; Watanabe, K.; Minoshima, T.; Yaji, K.

    2010-12-01

    The apex of a flare loop is one of important regions to understand particle acceleration in solar flares, under the framework of the flare model based on magnetic reconnection. At that portion, nonthermal emissions are observed in hard X-rays and microwave. These two emissions are originated from electrons accelerated/energized in different energy ranges. Hard X-rays (~ 50 - 100 keV ) are emitted by relatively lower-energy (~ 100 keV) accelerated electrons. On the other hand, microwaves (17 GHz) are emitted by relatively higher-energy (~ 1 MeV) electrons. The locations (heights) of these two emitting regions impose considerable constraints on the acceleration/transport/loss processes of electrons in solar flares. To compare hard X-ray and microwave sources, we chose twenty-three events among all events detected by Nobeyama Radio Heliograph (NoRH) during the almost whole period of its operation (1992 - 2008). The criteria are (1) limb event, (2) simultaneous observation with Yohkoh/HXT or RHESSI, (3) enough number of photons in the energy range of 33 - 53 keV, and (4) microwave source large enough to resolve the flare loop into footpoint and looptop sources. However, only seven events among them can be used for this study. The remaining sixteen events are displaced from the list due to no hard X-ray looptop source, too complex structure of multiple loops, and so force. Among the seven events, six events show that the looptop hard X-ray source is located at a higher altitude than the looptop microwave source. This result suggests that lower-energy accelerated electrons (~ 100 keV) are located at a higher altitude than higher-energy (~ 1 MeV) electrons. What makes this height difference? We discuss the cause of it from various kinds of viewpoints, e.g. emission mechanism, trapping effect, transport process, loss process.

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

    Science.gov (United States)

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

    2002-04-01

    We describe the first demonstration of a new stable, kHz femtosecond laser-plasma source of hard x-ray continuum and Kα 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, Kα and Kβ 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. K X-ray fluorescent source for energy-channel calibration of the spectrometer

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A new K X-ray fluorescent source for calibrating the X or γ-ray multichannel analyzer spectrometer is introduced. A detailed description of the K fluorescent source device is given. The calibration method used and experimental results obtained are presented. The purity and efficiency of K fluorescence photons from this device are discussed. This new fluorescent source may be used as a substitute for radioactive nuclides for the energy-channel calibration of some MCA spectrometers.

  10. Characterisation of flash X-ray source generated by Kali-1000 Pulse Power System

    Science.gov (United States)

    Satyanarayana, N.; Durga Prasada Rao, A.; Mittal, K. C.

    2016-02-01

    The electron beam-driven Rod Pinch Diode (RPD) is presently fielded on KALI-1000 Pulse Power System at Bhabha Atomic Research Centre, Visakhapatnam and is a leading candidate for future flash X-ray radiographic sources. The diode is capable of producing less than 2-mm radiation spot sizes and greater than 350 milli rads of dose measured at 1 m from the X-ray source. KALI-1000 Pulse Power Source is capable of delivering up to 600 kV using a Tesla Transformer with Demineralized Insulated Transmission Line (DITL), the diode typically operates between 250-330 kV . Since the radiation dose has a power-law dependence on diode voltage, this limits the dose production on KALI-1000 system. Radiation dose with angular variation is measured using thermoluminescent detectors (TLD's) and the X-ray spot size is measured using pin hole arrangement with image plate (IP) to obtain the time-integrated source profile as well as a time-resolved spot diagnostic. An X-ray pinhole camera was used to pick out where the energetic e-beam connects to the anode. Ideally the diode should function such that the radiation is emitted from the tip. The camera was mounted perpendicular to the machine's axis to view the radiation from the tip. Comparison of the spot sizes of the X-ray sources obtained by the pin hole and rolled edge arrangements was carried and results obtained by both the techniques are with in ± 10% of the average values.

  11. Numerical simulations of chromospheric hard X-ray source sizes in solar flares

    CERN Document Server

    Battaglia, Marina; Fletcher, Lyndsay; MacKinnon, Alec L

    2012-01-01

    X-ray observations are a powerful diagnostic tool for transport, acceleration, and heating of electrons in solar flares. Height and size measurements of X-ray footpoints sources can be used to determine the chromospheric density and constrain the parameters of magnetic field convergence and electron pitch-angle evolution. We investigate the influence of the chromospheric density, magnetic mirroring and collisional pitch-angle scattering on the size of X-ray sources. The time-independent Fokker-Planck equation for electron transport is solved numerically and analytically to find the electron distribution as a function of height above the photosphere. From this distribution, the expected X-ray flux as a function of height, its peak height and full width at half maximum are calculated and compared with RHESSI observations. A purely instrumental explanation for the observed source size was ruled out by using simulated RHESSI images. We find that magnetic mirroring and collisional pitch-angle scattering tend to ch...

  12. An Ultraluminous X-ray Source Powered by An Accreting Neutron Star

    CERN Document Server

    Bachetti, M; Walton, D J; Grefenstette, B W; Chakrabarty, D; Fürst, F; Barret, D; Beloborodov, A; Boggs, S E; Christensen, F E; Craig, W W; Fabian, A C; Hailey, C J; Hornschemeier, A; Kaspi, V; Kulkarni, S R; Maccarone, T; Miller, J M; Rana, V; Stern, D; Tendulkar, S P; Tomsick, J; Webb, N A; Zhang, W W

    2014-01-01

    Ultraluminous X-ray sources (ULX) are off-nuclear point sources in nearby galaxies whose X-ray luminosity exceeds the theoretical maximum for spherical infall (the Eddington limit) onto stellar-mass black holes. Their luminosity ranges from $10^{40}$ erg s$^{-1} $10^{40}$ erg s$^{-1}$), which require black hole masses MBH >50 solar masses and/or significant departures from the standard thin disk accretion that powers bright Galactic X-ray binaries. Here we report broadband X-ray observations of the nuclear region of the galaxy M82, which contains two bright ULXs. The observations reveal pulsations of average period 1.37 s with a 2.5-day sinusoidal modulation. The pulsations result from the rotation of a magnetized neutron star, and the modulation arises from its binary orbit. The pulsed flux alone corresponds to $L_X$(3 - 30 keV) = $4.9 \\times 10^{39}$ erg s$^{-1}$. The pulsating source is spatially coincident with a variable ULX which can reach $L_X$ (0.3 - 10 keV) = $1.8 \\times 10^{40}$ erg s$^{-1}$. This ...

  13. Development of an ultrashort table-top electron and x-ray source pumped by laser

    Science.gov (United States)

    Girardeau-Montaut, Jean-Pierre; Kiraly, Bela; Girardeau-Montaut, Claire; Leboutet, Hubert

    1999-09-01

    We report on the design of the CIBER-X source which is a new laser driven table-top ultrashort electron and x-ray source. X-ray pulses are produced by a three-step process which consists of the electron pulse production from a thin metallic photocathode illuminated by picosecond 213 nm laser pulses with 16 ps duration. The electrons are accelerated in the diode by a cw electric field of 11 MV/m, and the photoinjector produces a single 70 - 100 keV electron pulse of approximately 0,5 nC and approximately 20 A peak current at a repetition rate of 10 Hz. The gun is a standard Pierce diode electrode type, the electrons leaving the diode through a hole made in the anode. The electrons are then transported along a path approximately 20 cm long, and are focused by two magnetic fields produced by electromagnetic coils. Finally, the x-rays are produced by the impact of electrons on a massive target of Tm. Simulations of geometrical and energetic characteristics of the complete source were done previously with assistance of the code PIXEL1. Finally, experimental performances of electron and x-ray bursts are discussed.

  14. New flaring of an ultraluminous X-ray source in NGC 1365

    CERN Document Server

    Soria, R; Risaliti, G; Fabbiano, G; King, A R; La Parola, V; Zezas, A

    2007-01-01

    We have studied a highly variable ultraluminous X-ray source (ULX) in the Fornax galaxy NGC 1365, with a series of 12 Chandra and XMM-Newton observations between 2002 and 2006. In 2006 April, the source peaked at a luminosity ~ 3 x 10^{40} erg/s in the 0.3-10 keV band (similar to the maximum luminosity found by ASCA in 1995), and declined on an e-folding timescale ~ 3 days. The X-ray spectrum is always dominated by a broad power-law-like component. When the source is seen at X-ray luminosities ~ 10^{40} erg/s, an additional soft thermal component (which we interpret as emission from the accretion disk) contributes ~ 1/4 of the X-ray flux; when the luminosity is higher, ~ 3 x 10^{40} erg/s, the thermal component is not detected and must contribute < 10% of the flux. At the beginning of the decline, ionized absorption is detected around 0.5-2 keV; it is a possible signature of a massive outflow. The power-law is always hard, with a photon index Gamma ~ 1.7 (and even flatter at times), as is generally the cas...

  15. 2XMM Ultraluminous X-Ray Source Candidates in Nearby Galaxies

    CERN Document Server

    Walton, D J; Mateos, S; Heard, V

    2011-01-01

    Ultraluminous X-ray sources (ULXs) are some of the most enigmatic X-ray bright sources known to date. It is generally accepted that they cannot host black holes as large as those associated with active galaxies, but they appear to be significantly more luminous than their better understood Galactic X-ray binary (XRB) cousins, while displaying an intriguing combination of differences and similarities with them. Through studying large, representative samples of these sources we may hope to enhance our understanding of them. To this end, we derive a large catalogue of 650 X-ray detections of 470 ULX candidates, located in 238 nearby galaxies, by cross correlating the 2XMM Serendipitous Survey with the Third Reference Catalogue of Bright Galaxies. The presented dedicated catalogue offers a significant improvement over those previously published both in terms of number and the contribution of background contaminants, e.g. distant quasars, which we estimate to be at most 24 per cent, but more likely ~17 per cent. T...

  16. On the physical nature of the source of ultraluminous X-ray pulsations

    Science.gov (United States)

    Ter-Kazarian, G.

    2016-01-01

    To reconcile the observed unusual high luminosity of NuSTAR X-ray pulsations from M82X-2 with the most extreme violation of the Eddington limit, and in view that the persistent X-ray radiation from M82X-2 almost precludes the possibility of common pulsars, we tackle the problem by the implications of microscopic theory of black hole (MTBH). The preceding developments of MTBH are proved to be quite fruitful for the physics of ultra-high energy (UHE) cosmic-rays. Namely, replacing a central singularity by the infrastructures inside event horizon, subject to certain rules, MTBH explains the origin of ZeV-neutrinos which are of vital interest for the source of UHE-particles. The M82X-2 is assumed to be a spinning intermediate mass black hole resided in final stage of growth. Then, the thermal blackbody X-ray emission, arisen due to the rotational kinetic energy of black hole, escapes from event horizon through the vista to outside world, which is detected as ultraluminous X-ray pulsations. The M82X-2 indeed releases ˜99.6 % of its pulsed radiative energy predominantly in the X-ray bandpass 0.3-30 keV. We derive a pulse profile and give a quantitative account of energetics and orbital parameters of the semi-detached X-ray binary containing a primary accretor M82X-2 of inferred mass M≃138.5-226 M_{⊙} and secondary massive, M2> 48.3-64.9 M_{⊙}, O/B-type donor star with radius of R> 22.1-25.7 R_{⊙}, respectively. We compute the torque added to M82X-2 per unit mass of accreted matter which yields the measured spin-up rate.

  17. Toward Femtosecond X-ray Spectroscopy at the Advanced Light Source

    Energy Technology Data Exchange (ETDEWEB)

    Chong, Henry Herng Wei

    2004-04-16

    The realization of tunable, ultrashort pulse x-ray sources promises to open new venues of science and to shed new light on long-standing problems in condensed matter physics and chemistry. Fundamentally new information can now be accessed. Used in a pump-probe spectroscopy, ultrashort x-ray pulses provide a means to monitor atomic rearrangement and changes in electronic structure in condensed-matter and chemical systems on the physically-limiting time-scales of atomic motion. This opens the way for the study of fast structural dynamics and the role they play in phase transitions, chemical reactions and the emergence of exotic properties in materials with strongly interacting degrees of freedom. The ultrashort pulse x-ray source developed at the Advanced Light Source at the Lawrence Berkeley Laboratory is based on electron slicing in storage rings, and generates {approx}100 femtosecond pulses of synchrotron radiation spanning wavelengths from the far-infrared to the hard x-ray region of the electromagnetic spectrum. The tunability of the source allows for the adaptation of a broad range of static x-ray spectroscopies to useful pump-probe measurements. Initial experiments are attempted on transition metal complexes that exhibit relatively large structural changes upon photo-excitation and which have excited-state evolution determined by strongly interacting structural, electronic and magnetic degrees of freedom. Specifically, iron(II) complexes undergo a spin-crossover transition upon optical irradiation. The dynamics of the transition involve a metal-to-ligand charge transfer, a {Delta}S=2 change in magnetic moment and 10% bond dilation in the first coordination shell of the iron. Studies of the electronic dynamics are studied with time-resolved optical absorption measurements. The current progress of time-resolved structural studies to complete the picture of the spin-crossover transition is presented.

  18. Toward Femtosecond X-ray Spectroscopy at the Advanced Light Source

    Energy Technology Data Exchange (ETDEWEB)

    Chong, Henry Herng Wei [Univ. of California, Berkeley, CA (United States)

    2004-01-01

    The realization of tunable, ultrashort pulse x-ray sources promises to open new venues of science and to shed new light on long-standing problems in condensed matter physics and chemistry. Fundamentally new information can now be accessed. Used in a pump-probe spectroscopy, ultrashort x-ray pulses provide a means to monitor atomic rearrangement and changes in electronic structure in condensed-matter and chemical systems on the physically-limiting time-scales of atomic motion. This opens the way for the study of fast structural dynamics and the role they play in phase transitions, chemical reactions and the emergence of exotic properties in materials with strongly interacting degrees of freedom. The ultrashort pulse x-ray source developed at the Advanced Light Source at the Lawrence Berkeley Laboratory is based on electron slicing in storage rings, and generates ~100 femtosecond pulses of synchrotron radiation spanning wavelengths from the far-infrared to the hard x-ray region of the electromagnetic spectrum. The tunability of the source allows for the adaptation of a broad range of static x-ray spectroscopies to useful pump-probe measurements. Initial experiments are attempted on transition metal complexes that exhibit relatively large structural changes upon photo-excitation and which have excited-state evolution determined by strongly interacting structural, electronic and magnetic degrees of freedom. Specifically, iron(II) complexes undergo a spin-crossover transition upon optical irradiation. The dynamics of the transition involve a metal-to-ligand charge transfer, a ΔS=2 change in magnetic moment and 10% bond dilation in the first coordination shell of the iron. Studies of the electronic dynamics are studied with time-resolved optical absorption measurements. The current progress of time-resolved structural studies to complete the picture of the spin-crossover transition is presented.

  19. Phase contrast micro-CT with an ultrafast laser-based x-ray source

    Science.gov (United States)

    Toth, R.; Kieffer, J. C.; Krol, A.; Fourmaux, S.; Ozaki, T.; Ye, H.; Kincaid, R. E., Jr.; Rakhman, A.

    2005-08-01

    We investigated performance of ultrafast laser-based x-ray source for phase contrast imaging in 2D projection imaging and in enhanced micro-CT imaging. Good quality images were obtained, including images of small animals, in the single energy and multiple energy, in line phase-contrast enhancing geometry using x-ray line energy matching object thickness and density. Phase information has been inferred from images obtained at the same x-ray energy but at different object-to-detector distances and also from images obtained at the same object-to-detector distance but with different K-alpha line energies. Ultrafast laser-based, compact, x-ray source is a promising technique for micro-CT systems. Its utilization might result in faster scans with lower radiation dose, better spatial and contrast resolution and also femtosecond temporal resolution. In addition, it might allow practical implementation of dual-energy and phase-contrast imaging micro-CT that is not possible with conventional micro-CT.

  20. The Project PLASMONX for Plasma Acceleration Experiments and a Thomson X-Ray Source at SPARC

    CERN Document Server

    Serafini, Luca; Alessandria, Franco; Bacci, Alberto; Baldeschi, Walter; Barbini, Alessandro; Bellaveglia, Marco; Bertolucci, Sergio; Biagini, Maria; Boni, Roberto; Bonifacio, Rodolfo; Boscolo, Ilario; Boscolo, Manuela; Bottigli, Ubaldo; Broggi, Francesco; Castellano, Michele; Cecchetti, Carlo A; Cialdi, Simone; Clozza, Alberto; De Martinis, Carlo; Di Pirro, Giampiero; Drago, Alessandro; Esposito, Adolfo; Ferrario, Massimo; Ficcadenti, L; Filippetto, Daniele; Fusco, Valeria; Galimberti, Marco; Gallo, Alessandro; Gatti, Giancarlo; Ghigo, Andrea; Giove, Dario; Giulietti, Antonio; Giulietti, Danilo; Gizzi, Leonida A; Golosio, Bruno; Guiducci, Susanna; Incurvati, Maurizio; Köster, Petra; Labate, Luca; Ligi, Carlo; Marcellini, Fabio; Maroli, Cesare; Mauri, Marco; Migliorati, Mauro; Mostacci, Andrea; Oliva, Pier N; Palumbo, Luigi; Pellegrino, Luigi; Petrillo, Vittoria; Piovella, Nicola; Poggiu, Angela; Pozzoli, Roberto; Preger, Miro; Ricci, Ruggero; Rome, Massimiliano; Rossi, Antonella; Sanelli, Claudio; Serio, Mario; Sgamma, Francesco; Spataro, Bruno; Stecchi, Alessandro; Stella, Angelo; Stumbo, Simone; Tazzioli, Franco; Tommasini, Paolo; Vaccarezza, Cristina; Vescovi, Mario; Vicario, Carlo

    2005-01-01

    We present the status of the activity on the project PLASMONX, which foresees the installation of a multi-TW Ti:Sa laser system at the CNR-ILIL laboratory to conduct plasma acceleration experiments and the construction of an additional beam line at SPARC to develop a Thomson X-ray source at INFN-LNF. After pursuing self-injection experiments at ILIL, when the electron beam at SPARC will be available the SPARC laser system will be upgraded to TW power level in order to conduct either external injection plasma acceleration experiments and ultra-bright X-ray pulse generation with the Thomson source. Results of numerical simulations modeling the interaction of the SPARC electron beam and the counter-propagating laser beam are presented with detailed discussion of the monochromatic X-ray beam spectra generated by Compton backscattering: X-ray energies are tunable in the range 20 to 1000 keV, with pulse duration from 30 fs to 20 ps. Preliminary simulations of plasma acceleration with self-injection are illustrated,...

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

    CERN Document Server

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

    2002-01-01

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

  2. Study of correlation between ultraluminous X-ray sources and their host galaxies

    Science.gov (United States)

    Priajana, I. G. P. M.; Wulandari, H. R. T.

    2016-11-01

    Ultraluminous X-ray sources (ULXs) are defined as non-nuclear point-source objects with apparent X-ray luminosities, Lx > 2×1039 erg s-1, in the 0.3-8 keV band. ULXs are often explained using two different scenarios, (1) ULXs as intermediate mass black hole (IMBH) with sub-Eddington accretion and (2) ULXs as stellar mass black hole with super-Eddington accretion. There are two methods that commonly used to study the characteristics of ULXs. One method is to study the X-ray spectra of ULXs, to determine the characteristics of their accretion flows from fitting their spectra using available spectral models. The other method is to investigate how population of ULXs correlate with their environment, in this case their host galaxies. Our goal is to find correlation between ULXs and the properties of its host galaxies, for example with Star Formation Rate (SFR), mass and morphology. From this study we found a positive correlation between ULXs number and SFR. From X-ray luminosity function, we found upper limit of black holes mass that power ULXs is about 100 M⊙.

  3. Workshops on Science Enabled by a Coherent, CW, Synchrotron X-ray Source, June 2011

    Energy Technology Data Exchange (ETDEWEB)

    Brock, Joel

    2012-01-03

    In June of 2011 we held six two-day workshops called "XDL-2011: Science at the Hard X-ray Diffraction Limit". The six workshops covered (1) Diffraction-based imaging techniques, (2) Biomolecular structure from non-crystalline materials, (3) Ultra-fast science, (4) High-pressure science, (5) Materials research with nano-beams and (6) X-ray photon correlation spectroscopy (XPCS), In each workshop, invited speaker from around the world presented examples of novel experiments that require a CW, diffraction-limited source. During the workshop, each invited speaker provided a one-page description of the experiment and an illustrative graphic. The experiments identified by the workshops demonstrate the broad and deep scientific case for a CW coherent synchrotron x-ray source. The next step is to perform detailed simulations of the best of these ideas to test them quantitatively and to guide detailed x-ray beam-line designs. These designs are the first step toward developing detailed facility designs and cost estimates.

  4. Monochromatic computed tomography with a compact laser-driven X-ray source.

    Science.gov (United States)

    Achterhold, K; Bech, M; Schleede, S; Potdevin, G; Ruth, R; Loewen, R; Pfeiffer, F

    2013-01-01

    A laser-driven electron-storage ring can produce nearly monochromatic, tunable X-rays in the keV energy regime by inverse Compton scattering. The small footprint, relative low cost and excellent beam quality provide the prospect for valuable preclinical use in radiography and tomography. The monochromaticity of the beam prevents beam hardening effects that are a serious problem in quantitative determination of absorption coefficients. These values are important e.g. for osteoporosis risk assessment. Here, we report quantitative computed tomography (CT) measurements using a laser-driven compact electron-storage ring X-ray source. The experimental results obtained for quantitative CT measurements on mass absorption coefficients in a phantom sample are compared to results from a rotating anode X-ray tube generator at various peak voltages. The findings confirm that a laser-driven electron-storage ring X-ray source can indeed yield much higher CT image quality, particularly if quantitative aspects of computed tomographic imaging are considered.

  5. On Physical Nature of the Source of Ultraluminous X-ray Pulsations

    CERN Document Server

    Ter-Kazarian, G

    2015-01-01

    To reconcile the observed unusual high luminosity of periodic source M82X-2 of the first NuSTAR ultraluminous X-ray pulsations with the most extreme violation of the Eddington limit, and in view that a persistent X-ray radiation from M82X-2 ultimately precludes the possibility of typical pulsars, we tackle the problem by the implications of "microscopic theory of black hole", the preceding developments of which are of vital interest for the physics of ultra-high energy (UHE) cosmic-rays. Replacing a central singularity by the infrastructures inside event horizon, subject to certain rules, MTBH explains the origin of ZeV-neutrinos which are of vital interest for the source of UHE- particles. Withal, M82X-2 is assumed to be a spinning intermediate mass black hole resided in final stage of growth. Then the thermal blackbody X-ray emission, arisen due to the rotational kinetic energy of black hole, escapes from event horizon through the vista to outside world that detected as ultraluminous X-ray pulsations. The M...

  6. 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

    clear Chandra counterparts for 58 NuSTAR sources and assign candidate counterparts for the remaining 19. The NuSTAR survey reaches X-ray luminosities of similar to 4x and similar to 8 x 1032 erg s-1 at the GC (8 kpc) in the 3-10 and 10-40 keV bands, respectively. The source list includes three...

  7. Proposal to DOE Basic Energy Sciences: Ultrafast X-ray science facility at the Advanced Light Source

    Energy Technology Data Exchange (ETDEWEB)

    Schoenlein, Robert W.; Falcone, Roger W.; Abela, R.; Alivisatos, A.P.; Belkacem, A.; Berrah, N.; Bozek, J.; Bressler, C.; Cavalleri, A.; Chergui, M.; Glover, T.E.; Heimann, P.A.; Hepburn, J.; Larsson, J.; Lee, R.W.; McCusker, J.; Padmore, H.A.; Pattison, P.; Pratt, S.T.; Shank, C.V.; Wark, J.; Chang, Z.; Robin, D.W.; Schlueter, R.D.; Zholents, A.A.; Zolotorev, M.S.

    2001-12-12

    We propose to develop a true user facility for ultrafast x-ray science at the Advanced Light Source. This facility will be unique in the world, and will fill a critical need for the growing ultrafast x-ray research community. The development of this facility builds upon the expertise from long-standing research efforts in ultrafast x-ray spectroscopy and the development of femtosecond x-ray sources and techniques at both the Lawrence Berkeley National Laboratory and at U.C. Berkeley. In particular, the technical feasibility of a femtosecond x-ray beamline at the ALS has already been demonstrated, and existing ultrafast laser technology will enable such a beamline to operate near the practical limit for femtosecond x-ray flux and brightness from a 3rd generation synchrotron.

  8. UNVEILING THE NATURE OF THE UNIDENTIFIED GAMMA-RAY SOURCES. IV. THE SWIFT CATALOG OF POTENTIAL X-RAY COUNTERPARTS

    Energy Technology Data Exchange (ETDEWEB)

    Paggi, A.; D' Abrusco, R.; Smith, H. A. [Harvard-Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 (United States); Massaro, F.; Funk, S. [SLAC National Laboratory and Kavli Institute for Particle Astrophysics and Cosmology, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States); Masetti, N. [INAF-Istituto di Astrofisica Spaziale e Fisica Cosmica di Bologna, via Gobetti 101, I-40129 Bologna (Italy); Giroletti, M. [INAF Istituto di Radioastronomia, via Gobetti 101, I-40129 Bologna (Italy); Tosti, G., E-mail: apaggi@cfa.harvard.edu [Dipartimento di Fisica, Università degli Studi di Perugia, I-06123 Perugia (Italy)

    2013-11-01

    A significant fraction (∼30%) of the high-energy γ-ray sources listed in the second Fermi Large Area Telescope (LAT) catalog are still of unknown origin, having not yet been associated with counterparts at lower energies. To investigate the nature of these enigmatic sources, we present an extensive search of X-ray sources lying in the positional uncertainty region of a selected sample of these unidentified gamma-ray sources (UGSs) that makes use of all available observations performed by the Swift X-ray Telescope before 2013 March 31, available for 205 UGSs. To detect the fainter sources, we merged all the observations covering the Fermi LAT positional uncertainty region at a 95% level of confidence of each UGS. This yields a catalog of 357 X-ray sources, finding candidate X-ray counterparts for ∼70% of the selected sample. In particular, 25% of the UGSs feature a single X-ray source within their positional uncertainty region, while 45% have multiple X-ray sources. For each X-ray source, we also looked in the corresponding Swift UVOT merged images for optical and ultraviolet counterparts, also performing source photometry. We found ultraviolet-optical correspondences for ∼70% of the X-ray sources. We searched several major radio, infrared, optical, and ultraviolet surveys for possible counterparts within the positional error of the sources in the X-ray catalog to obtain additional information on their nature. Applying the kernel density estimation technique to infrared colors of Wide-Field Infrared Survey Explorer counterparts of our X-ray sources we select six γ-ray blazar candidates. In addition, comparing our results with previous analyses, we select 11 additional γ-ray blazar candidates.

  9. Development of a compact laser-produced plasma soft X-ray source for radiobiology experiments

    Energy Technology Data Exchange (ETDEWEB)

    Adjei, Daniel, E-mail: nana.adjeidan@gmail.com [Institute of Optoelectronics, Military University of Technology, 2, Kaliskiego Str., 00-908 Warsaw (Poland); Radiation Protection Institute, Ghana Atomic Energy Commission, P.O. Box LG 80, Legon, Accra (Ghana); Ayele, Mesfin Getachew; Wachulak, Przemyslaw; Bartnik, Andrzej; Wegrzynski, Łukasz; Fiedorowicz, Henryk [Institute of Optoelectronics, Military University of Technology, 2, Kaliskiego Str., 00-908 Warsaw (Poland); Vyšín, Luděk [Institute of Physics, Czech Academy of Sciences, Na Slovance 2, 182 21 Prague 8 (Czech Republic); Faculty of Nuclear Sciences and Engineering Physics, Czech Technical University in Prague, Břehová 7, 115 19 Prague 1 (Czech Republic); Wiechec, Anna; Lekki, Janusz; Kwiatek, Wojciech M. [Institute of Nuclear Physics, Polish Academy of Sciences, 152, Radzikowskiego Str., 31-342 Cracow (Poland); Pina, Ladislav [Faculty of Nuclear Sciences and Engineering Physics, Czech Technical University in Prague, Břehová 7, 115 19 Prague 1 (Czech Republic); Davídková, Marie [Institute of Nuclear Physics, Czech Academy of Sciences, Řež (Czech Republic); Juha, Libor [Institute of Physics, Czech Academy of Sciences, Na Slovance 2, 182 21 Prague 8 (Czech Republic)

    2015-12-01

    A desk-top laser-produced plasma (LPP) source of soft X-rays (SXR) has been developed for radiobiology research. The source is based on a double-stream gas puff target, irradiated with the focused beam of a commercial Nd:YAG laser. The source has been optimized to get a maximum photon emission from LPP in the X-ray “water window” spectral wavelength range from 2.3 nm (i.e., an absorption edge of oxygen) to 4.4 nm (i.e., an absorption edge of carbon) (280–540 eV in photon energy units) by using argon gas-puff target and spectral filtering by free-standing thin foils. The present source delivers nanosecond pulses of soft X-rays at a fluence of about 4.2 × 10{sup 3} photons/μm{sup 2}/pulse on a sample placed inside the vacuum chamber. In this paper, the source design, radiation output characterization measurements and initial irradiation experiments are described. The source can be useful in addressing observations related to biomolecular, cellular and organisms’ sensitivity to pulsed radiation in the “water window”, where carbon atoms absorb X-rays more strongly than the oxygen, mostly present in water. The combination of the SXR source and the radiobiology irradiation layout, reported in this article, make possible a systematic investigation of relationships between direct and indirect action of ionizing radiation, an increase of a local dose in carbon-rich compartments of the cell (e.g., lipid membranes), an experimental estimation of a particular role of the Auger effect (in particular in carbon atoms) in the damage to biological systems, and the study of ionization/excitation-density (LET – Linear Energy Transfer) and dose-rate effects in radiobiology.

  10. Development of a compact laser-produced plasma soft X-ray source for radiobiology experiments

    Science.gov (United States)

    Adjei, Daniel; Ayele, Mesfin Getachew; Wachulak, Przemyslaw; Bartnik, Andrzej; Wegrzynski, Łukasz; Fiedorowicz, Henryk; Vyšín, Luděk; Wiechec, Anna; Lekki, Janusz; Kwiatek, Wojciech M.; Pina, Ladislav; Davídková, Marie; Juha, Libor

    2015-12-01

    A desk-top laser-produced plasma (LPP) source of soft X-rays (SXR) has been developed for radiobiology research. The source is based on a double-stream gas puff target, irradiated with the focused beam of a commercial Nd:YAG laser. The source has been optimized to get a maximum photon emission from LPP in the X-ray "water window" spectral wavelength range from 2.3 nm (i.e., an absorption edge of oxygen) to 4.4 nm (i.e., an absorption edge of carbon) (280-540 eV in photon energy units) by using argon gas-puff target and spectral filtering by free-standing thin foils. The present source delivers nanosecond pulses of soft X-rays at a fluence of about 4.2 × 103 photons/μm2/pulse on a sample placed inside the vacuum chamber. In this paper, the source design, radiation output characterization measurements and initial irradiation experiments are described. The source can be useful in addressing observations related to biomolecular, cellular and organisms' sensitivity to pulsed radiation in the "water window", where carbon atoms absorb X-rays more strongly than the oxygen, mostly present in water. The combination of the SXR source and the radiobiology irradiation layout, reported in this article, make possible a systematic investigation of relationships between direct and indirect action of ionizing radiation, an increase of a local dose in carbon-rich compartments of the cell (e.g., lipid membranes), an experimental estimation of a particular role of the Auger effect (in particular in carbon atoms) in the damage to biological systems, and the study of ionization/excitation-density (LET - Linear Energy Transfer) and dose-rate effects in radiobiology.

  11. Laser-driven x-ray and neutron source development for industrial applications of plasma accelerators

    Science.gov (United States)

    Brenner, C. M.; Mirfayzi, S. R.; Rusby, D. R.; Armstrong, C.; Alejo, A.; Wilson, L. A.; Clarke, R.; Ahmed, H.; Butler, N. M. H.; Haddock, D.; Higginson, A.; McClymont, A.; Murphy, C.; Notley, M.; Oliver, P.; Allott, R.; Hernandez-Gomez, C.; Kar, S.; McKenna, P.; Neely, D.

    2016-01-01

    Pulsed beams of energetic x-rays and neutrons from intense laser interactions with solid foils are promising for applications where bright, small emission area sources, capable of multi-modal delivery are ideal. Possible end users of laser-driven multi-modal sources are those requiring advanced non-destructive inspection techniques in industry sectors of high value commerce such as aerospace, nuclear and advanced manufacturing. We report on experimental work that demonstrates multi-modal operation of high power laser-solid interactions for neutron and x-ray beam generation. Measurements and Monte Carlo radiation transport simulations show that neutron yield is increased by a factor ~2 when a 1 mm copper foil is placed behind a 2 mm lithium foil, compared to using a 2 cm block of lithium only. We explore x-ray generation with a 10 picosecond drive pulse in order to tailor the spectral content for radiography with medium density alloy metals. The impact of using  >1 ps pulse duration on laser-accelerated electron beam generation and transport is discussed alongside the optimisation of subsequent bremsstrahlung emission in thin, high atomic number target foils. X-ray spectra are deconvolved from spectrometer measurements and simulation data generated using the GEANT4 Monte Carlo code. We also demonstrate the unique capability of laser-driven x-rays in being able to deliver single pulse high spatial resolution projection imaging of thick metallic objects. Active detector radiographic imaging of industrially relevant sample objects with a 10 ps drive pulse is presented for the first time, demonstrating that features of 200 μm size are resolved when projected at high magnification.

  12. 3D nanoscale imaging of biological samples with laboratory-based soft X-ray sources

    Science.gov (United States)

    Dehlinger, Aurélie; Blechschmidt, Anne; Grötzsch, Daniel; Jung, Robert; Kanngießer, Birgit; Seim, Christian; Stiel, Holger

    2015-09-01

    In microscopy, where the theoretical resolution limit depends on the wavelength of the probing light, radiation in the soft X-ray regime can be used to analyze samples that cannot be resolved with visible light microscopes. In the case of soft X-ray microscopy in the water-window, the energy range of the radiation lies between the absorption edges of carbon (at 284 eV, 4.36 nm) and oxygen (543 eV, 2.34 nm). As a result, carbon-based structures, such as biological samples, posses a strong absorption, whereas e.g. water is more transparent to this radiation. Microscopy in the water-window, therefore, allows the structural investigation of aqueous samples with resolutions of a few tens of nanometers and a penetration depth of up to 10μm. The development of highly brilliant laser-produced plasma-sources has enabled the transfer of Xray microscopy, that was formerly bound to synchrotron sources, to the laboratory, which opens the access of this method to a broader scientific community. The Laboratory Transmission X-ray Microscope at the Berlin Laboratory for innovative X-ray technologies (BLiX) runs with a laser produced nitrogen plasma that emits radiation in the soft X-ray regime. The mentioned high penetration depth can be exploited to analyze biological samples in their natural state and with several projection angles. The obtained tomogram is the key to a more precise and global analysis of samples originating from various fields of life science.

  13. The x-ray polarimeter instrument on board the Polarimeter for Relativistic Astrophysical X-ray Sources (PRAXyS) mission

    Science.gov (United States)

    Hill, J. E.; Black, J. K.; Jahoda, K.; Tamagawa, T.; Iwakiri, W.; Kitaguchi, T.; Kubota, M.; Kaaret, P.; McCurdy, R.; Miles, D. M.; Okajima, T.; Soong, Y.; Olsen, L.; Sparr, L.; Mosely, S. J.; Nolan, D.

    2016-07-01

    The Polarimeter for Relativistic Astrophysical X-ray Sources (PRAXyS) is one of three Small Explorer (SMEX) missions selected by NASA for Phase A study. The PRAXyS observatory carries an X-ray Polarimeter Instrument (XPI) capable of measuring the linear polarization from a variety of high energy sources, including black holes, neutron stars, and supernova remnants. The XPI is comprised of two identical mirror-Time Projection Chamber (TPC) polarimeter telescopes with a system effective area of 124 cm2 at 3 keV, capable of photon limited observations for sources as faint as 1 mCrab. The XPI is built with well-established technologies. This paper will describe the performance of the XPI flight mirror with the engineering test unit polarimeter.

  14. Ultra-Luminous X-Ray Sources in the Most Metal Poor Galaxies

    CERN Document Server

    Prestwich, A H; Zezas, A; Jackson, F E; Roberts, T P; Foltz, R; Linden, T; Kalogera, V

    2013-01-01

    Ultra-Luminous X-ray sources (ULX) are X-ray binaries with Lx>1E^39 ergs/s. The most spectacular examples of ULX occur in starburst galaxies and are now understood to be young, luminous High Mass X-ray Binaries. The conditions under which ULX form are poorly understood, but recent evidence suggests they may be more common in low metallicity systems. Here we investigate the hypothesis that ULX form preferentially in low metallicity galaxies by searching for ULX in a sample of Extremely Metal Poor Galaxies (XMPG) observed with the Chandra X-ray Observatory. XMPG are defined as galaxies with log(O/H)+12<7.65, or less than 5% solar. These are the most metal-deficient galaxies known, and a logical place to find ULX if they favor metal poor systems. We compare the number of ULX (corrected for background contamination) per unit of star formation (Nulx) in the XMPG sample with Nulx in a comparison sample of galaxies with higher metallicities taken from the Spitzer Infrared Galaxy Sample (SINGS). We find that ULX o...

  15. High-resolution x-ray photoemission electron microscopy at the Advanced Light Source

    Energy Technology Data Exchange (ETDEWEB)

    Stammler, T.; Anders, S.; Padmore, H.A. [Lawrence Berkeley National Lab., CA (United States); Stoehr, J. [IBM Almaden Research Center, San Jose, CA (United States); Scheinfein, M. [Arizona State Univ., Tempe, AZ (United States). Dept. of Physics and Astronomy; Ade, H. [North Carolina State Univ., Raleigh, NC (United States). Dept. of Physics

    1998-12-31

    X-ray Photoemission Electron Microscopy (X-PEEM) is a full-field imaging technique where the sample is illuminated by an x-ray beam and the photoemitted electrons are imaged on a screen by means of an electron optics. It therefore combines two well-established materials analysis techniques--photoemission electron microscopy (PEEM) and x-ray spectroscopy such as near edge x-ray absorption fine structure (NEXAFS) spectroscopy. This combination opens a wide field of new applications in materials research and has proven to be a powerful tool to investigate simultaneously topological, elemental, chemical state, and magnetic properties of surfaces, thin films, and multilayers at high spatial resolution. A new X-PEEM installed at the bend magnet beamline 7.3.1.1 at the Advanced Light Source (ALS) is designed for a spatial resolution of 20 nm and is currently under commissioning. An overview of the ongoing experimental program using X-PEEM in the field of materials research at the ALS is given by elemental and chemical bonding contrast imaging of hard disk coatings and sliders, field emission studies on diamond films as possible candidates for field-emission flat-panel displays, and the study of dewetting and decomposition phenomena of thin polymer blends and bilayers.

  16. Multiwavelength modelling the SED of supersoft X-ray sources. I. The method and examples

    CERN Document Server

    Skopal, Augustin

    2014-01-01

    Radiation of supersoft X-ray sources (SSS) dominates both the supersof X-ray and the far-UV domain. A fraction of their radiation can be reprocessed into the thermal nebular emission, seen in the spectrum from the near-UV to longer wavelengths. In the case of symbiotic X-ray binaries (SyXBs) a strong contribution from their cool giants is indicated in the optical/near-IR. In this paper I introduce a method of multiwavelength modelling the spectral energy distribution (SED) of SSSs from the supersoft X-rays to the near-IR with the aim to determine the physical parameters of their composite spectra. The method is demonstrated on two extragalactic SSSs, the SyXB RX J0059.1-7505 (LIN 358) in the Small Magellanic Cloud (SMC), RX J0439.8-6809 in the Large Magellanic Cloud (LMC) and two Galactic SSSs, the classical nova RX J2030.5+5237 (V1974 Cyg) during its supersoft phase and the classical symbiotic star RX J1601.6+6648 (AG Dra) during its quiescent phase. The multiwavelength approach overcomes the problem of the ...

  17. Radiography using a dense plasma focus device as a source of pulsed X-rays

    Science.gov (United States)

    Herrera, Julio; Castillo, Fermín; Gamboa, Isabel; Rangel, José

    2007-11-01

    Soft and hard X-ray emissions have been studied in the FN-II, which is a small dense plasma focus machine (5 kJ), operating at the Instituto de Ciencias Nucleares, UNAM, using aluminum filtered pin-hole cameras. Their angular distribution has been measured using TLD-200 dosimeters [1]. Their temporal evolution has been observed by means of a PIN diode, and scinltillators coupled to photomultipliers outside the discharge chamber. The X rays source can be concentrated by placing a needle on the end of the electrode. X-rays crossing across a 300 micron aluminum window, through the axis of the machine, can be used to obtain high contrast radiographs, with an average dose of 0.4 mGy per shot. In contrast, the average dose with a hollow cathode is 0.2 mGy per shot. This work is partially supported by grant IN105705 de la DGAPA-UNAM. [1] F. Castillo, J.J.E. Herrera, J. Rangel, I. Gamboa, G. Espinosa y J.I. Golzarri ``Angular Distribution of fusion products and X-rays emitted by a small dense plasma focus machine'' Journal of Applied Physics 101 013303-1-7 (2007).

  18. Development of synchrotron radiation as a high-intensity source for X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Huxley, H.E. [Brandeis Univ., Rosenstiel Center, Waltham, Massachusetts (United States); Holmes, K.C. [Max-Planck-Inst. fuer Medizinische Forschung, Heidelberg (Germany)

    1997-11-01

    Interest in the molecular mechanism of muscle contraction led to the search for an intense source of X-rays of 1-2 Aa wavelength so as to be able to examine the rich X-ray diffraction patterns given by muscles during contraction. This led to the first X-ray diffraction experiments using synchrotron radiation, carried out by Holmes, Rosenbaum and Witz at DESY, Hamburg, in September 1970. In the following years, the EMBL Outstation, to utilize synchrotron radiation for biological structure determination, was established at DESY and preliminary experiments on muscle were also carried out at NINA (Daresbury). The development of time-resolved techniques for muscle diffraction was first started in the MRC Molecular Biology Laboratory in Cambridge, using rotating-anode X-ray tubes, and was then greatly extended at the EMBL Outstation, Hamburg, using the storage ring DORIS. This was a very successful venture, and helped to drive the whole technology development and to interest other potential users in the technique. (au).

  19. Low-Energy Plasma Focus as a Tailored X-Ray Source

    Science.gov (United States)

    Zakaullah, M.; Alamgir, K.; Shafiq, M.; Sharif, M.; Waheed, A.; Murtaza, G.

    2000-06-01

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

  20. Optical Studies of Ultra Luminous X-ray Sources in NGC4490

    Science.gov (United States)

    Akyuz, Aysun; Avdan, Hasan; Avdan, Senay; Aksaker, Nazim

    2016-07-01

    We present optical studies of Ultraluminous X-ray sources (ULXs) in the spiral galaxy NGC4490 which is interacting with the irregular galaxy NGC 4485. ULXs are extra-nuclear, point-like X-ray sources with isotropic luminosities (Lx > 10 ^{39} erg s ^{-1}) above the Eddington limit for a 10 Msun black hole. HST/ACS/WFC and WFPC3 archival data have been analyzed to investigate the optical counterparts of five ULXs in NGC4490. Using relative astrometry the corrected ULX positions were derived only for three sources within the 1σ error radius of 0.5 arcsec on the HST images. We discuss the properties of three optical counterparts and constraints on their physical nature from multiband optical observations.

  1. Start-to-end simulation of x-ray radiation of a next generation light source using the real number of electrons

    Directory of Open Access Journals (Sweden)

    J. Qiang

    2014-03-01

    Full Text Available In this paper we report on start-to-end simulation of a next generation light source based on a high repetition rate free electron laser (FEL driven by a CW superconducting linac. The simulation integrated the entire system in a seamless start-to-end model, including birth of photoelectrons, transport of electron beam through 600 m of the accelerator beam delivery system, and generation of coherent x-ray radiation in a two-stage self-seeding undulator beam line. The entire simulation used the real number of electrons (∼2 billion electrons/bunch to capture the details of the physical shot noise without resorting to artificial filtering to suppress numerical noise. The simulation results shed light on several issues including the importance of space-charge effects near the laser heater and the reliability of x-ray radiation power predictions when using a smaller number of simulation particles. The results show that the microbunching instability in the linac can be controlled with 15 keV uncorrelated energy spread induced by a laser heater and demonstrate that high brightness and flux 1 nm x-ray radiation (∼10^{12}  photons/pulse with fully spatial and temporal coherence is achievable.

  2. Start-to-end simulation of x-ray radiation of a next generation light source using the real number of electrons

    Science.gov (United States)

    Qiang, J.; Corlett, J.; Mitchell, C. E.; Papadopoulos, C. F.; Penn, G.; Placidi, M.; Reinsch, M.; Ryne, R. D.; Sannibale, F.; Sun, C.; Venturini, M.; Emma, P.; Reiche, S.

    2014-03-01

    In this paper we report on start-to-end simulation of a next generation light source based on a high repetition rate free electron laser (FEL) driven by a CW superconducting linac. The simulation integrated the entire system in a seamless start-to-end model, including birth of photoelectrons, transport of electron beam through 600 m of the accelerator beam delivery system, and generation of coherent x-ray radiation in a two-stage self-seeding undulator beam line. The entire simulation used the real number of electrons (˜2 billion electrons/bunch) to capture the details of the physical shot noise without resorting to artificial filtering to suppress numerical noise. The simulation results shed light on several issues including the importance of space-charge effects near the laser heater and the reliability of x-ray radiation power predictions when using a smaller number of simulation particles. The results show that the microbunching instability in the linac can be controlled with 15 keV uncorrelated energy spread induced by a laser heater and demonstrate that high brightness and flux 1 nm x-ray radiation (˜1012 photons/pulse) with fully spatial and temporal coherence is achievable.

  3. Finding Rare AGN: X-ray Number Counts of Chandra Sources in Stripe 82

    CERN Document Server

    LaMassa, Stephanie M; Glikman, Eilat; Cappelluti, Nico; Civano, Francesca; Comastri, Andrea; Treister, Ezequiel; Arifin,; Boehringer, Hans; Cardamone, Carie; Chon, Gayoung; Kephart, Miranda; Murray, Stephen S; Richards, Gordon; Ross, Nic; Rozner, Joshua S; Schawinski, Kevin

    2012-01-01

    We present the first results of a wide area X-ray survey within the Sloan Digital Sky Survey (SDSS) Stripe 82, a 300 deg$^2$ region of the sky with a substantial investment in multi-wavelength coverage. We analyzed archival {\\it Chandra} observations that cover 7.5 deg$^2$ within Stripe 82 ("Stripe 82 ACX"), reaching 4.5$\\sigma$ flux limits of 7.9$\\times10^{-16}$, 3.4$\\times10^{-15}$ and 1.8$\\times10^{-15}$ erg s$^{-1}$ cm$^{-2}$ in the soft (0.5-2 keV), hard (2-7 keV) and full (0.5-7 keV) bands, to find 774, 239 and 1118 X-ray sources, respectively. Three hundred twenty-one sources are detected only in the full band and 9 sources are detected solely in the soft band. Utilizing data products from the {\\it Chandra} Source Catalog, we construct independent Log$N$-Log$S$ relationships, detailing the number density of X-ray sources as a function of flux, which show general agreement with previous {\\it Chandra} surveys. We compare the luminosity distribution of Stripe 82 ACX with the smaller, deeper CDF-S + E-CDFS...

  4. Measurement of the energy and power radiated by a pulsed blackbody x-ray source

    Directory of Open Access Journals (Sweden)

    H. C. Ives

    2006-11-01

    Full Text Available We have developed a diagnostic system that measures the spectrally integrated (i.e. the total energy and power radiated by a pulsed blackbody x-ray source. The total-energy-and-power (TEP diagnostic system is optimized for blackbody temperatures between 50 and 350 eV. The system can view apertured sources that radiate energies and powers as high as 2 MJ and 200 TW, respectively, and has been successfully tested at 0.84 MJ and 73 TW on the Z pulsed-power accelerator. The TEP system consists of two pinhole arrays, two silicon-diode detectors, and two thin-film nickel bolometers. Each of the two pinhole arrays is paired with a single silicon diode. Each array consists of a 38×38 square array of 10-μm-diameter pinholes in a 50-μm-thick tantalum plate. The arrays achromatically attenuate the x-ray flux by a factor of ∼1800. The use of such arrays for the attenuation of soft x rays was first proposed by Turner and co-workers [Rev. Sci. Instrum. 70, 656 (1999RSINAK0034-674810.1063/1.1149385]. The attenuated flux from each array illuminates its associated diode; the diode’s output current is recorded by a data-acquisition system with 0.6-ns time resolution. The arrays and diodes are located 19 and 24 m from the source, respectively. Because the diodes are designed to have an approximately flat spectral sensitivity, the output current from each diode is proportional to the x-ray power. The nickel bolometers are fielded at a slightly different angle from the array-diode combinations, and view (without pinhole attenuation the same x-ray source. The bolometers measure the total x-ray energy radiated by the source and—on every shot—provide an in situ calibration of the array-diode combinations. Two array-diode pairs and two bolometers are fielded to reduce random uncertainties. An analytic model (which accounts for pinhole-diffraction effects of the sensitivity of an array-diode combination is presented.

  5. Biostructural Science Inspired by Next-Generation X-Ray Sources.

    Science.gov (United States)

    Gruner, Sol M; Lattman, Eaton E

    2015-01-01

    Next-generation synchrotron radiation sources, such as X-ray free-electron lasers, energy recovery linacs, and ultra-low-emittance storage rings, are catalyzing novel methods of biomolecular microcrystallography and solution scattering. These methods are described and future trends are predicted. Importantly, there is a growing realization that serial microcrystallography and certain cutting-edge solution scattering experiments can be performed at existing storage ring sources by utilizing new technology. In this sense, next-generation sources are serving two distinct functions, namely, provision of new capabilities that require the newer sources and inspiration of new methods that can be performed at existing sources.

  6. The SPARC project: a high-brightness electron beam source at LNF to drive a SASE-FEL experiment

    Energy Technology Data Exchange (ETDEWEB)

    Alesini, D.; Bertolucci, S.; Biagini, M.E.; Biscari, C.; Boni, R.; Boscolo, M.; Castellano, M.; Clozza, A.; Di Pirro, G.; Drago, A.; Esposito, A.; Ferrario, M. E-mail: massimo.ferrario@lnf.infn.it; Fusco, V.; Gallo, A.; Ghigo, A.; Guiducci, S.; Incurvati, M.; Laurelli, P.; Ligi, C.; Marcellini, F.; Migliorati, M.; Milardi, C.; Palumbo, L.; Pellegrino, L.; Preger, M.; Raimondi, P.; Ricci, R.; Sanelli, C.; Sgamma, F.; Spataro, B.; Serio, M.; Stecchi, A.; Stella, A.; Tazzioli, F.; Vaccarezza, C.; Vescovi, M.; Vicario, C.; Zobov, M.; Acerbi, E.; Alessandria, F.; Barni, D.; Bellomo, G.; Boscolo, I.; Broggi, F.; Cialdi, S.; DeMartinis, C.; Giove, D.; Maroli, C.; Petrillo, V.; Rome' , M.; Serafini, L.; Chiadroni, E.; Felici, G.; Levi, D.; Mastrucci, M.; Mattioli, M.; Medici, G.; Petrarca, G.S.; Catani, L.; Cianchi, A.; D' Angelo, A.; Di Salvo, R.; Fantini, A.; Moricciani, D.; Schaerf, C.; Bartolini, R.; Ciocci, F.; Dattoli, G.; Doria, A.; Flora, F.; Gallerano, G.P.; Giannessi, L.; Giovenale, E.; Messina, G.; Mezi, L.; Ottaviani, P.L.; Picardi, L.; Quattromini, M.; Renieri, A.; Ronsivalle, C.; Avaldi, L.; Carbone, C.; Cricenti, A.; Pifferi, A.; Perfetti, P.; Prosperi, T.; Albertini, V. Rossi; Quaresima, C.; Zema, N

    2003-07-11

    The Project Sorgente Pulsata e Amplificata di Radiazione Coerente (SPARC), proposed by a collaboration among ENEA-INFN-CNR-Universita' di Tor Vergata-INFM-ST, was recently approved by the Italian Government and will be built at LNF. The aim of the project is to promote an R and D activity oriented to the development of a coherent ultra-brilliant X-ray source in Italy. This collaboration has identified a program founded on two main issues: the generation of ultra-high peak brightness electron beams and of resonant higher harmonics in the SASE-FEL process, as presented in this paper.

  7. Coherence properties of third and fourth generation X-ray sources. Theory and experiment

    Energy Technology Data Exchange (ETDEWEB)

    Singer, Andrej

    2013-06-15

    Interference effects are among the most fascinating optical phenomena. For instance, the butterflies and soap bubbles owe their beautiful colors to interference effects. They appear as a result of the superposition principle, valid in electrodynamics due to the linearity of the wave equation. If two waves interfere, the total radiation field is a sum of these two fields and depends strongly on the relative phases between these fields. While the oscillation frequency of individual fields is typically too large to be observed by a human eye or other detection systems, the phase differences between these fields manifest themselves as relatively slowly varying field strength modulations. These modulations can be detected, provided the oscillating frequencies of the superposed fields are similar. As such, the interference provides a superb measure of the phase differences of optical light, which may carry detailed information about a source or a scattering object. The ability of waves to interfere depends strongly on the degree of correlation between these waves, i.e. their mutual coherence. Until the middle of the 20th century, the coherence of light available to experimentalists was poor. A significant effort had to be made to extend the degree of coherence, which made the electromagnetic field determination using of the interference principle very challenging. Coherence is the defining feature of a laser, whose invention initiated a revolutionary development of experimental techniques based on interference, such as holography. Important contributions to this development were also provided by astronomists, as due to enormous intergalactic distances the radiation from stars has a high transverse coherence length at earth. With the construction of third generation synchrotron sources, partially coherent X-ray sources have become feasible. New areas of research utilizing highly coherent X-ray beams have emerged, including X-ray photon correlation spectroscopy (XPCS), X-ray

  8. Focused beam total reflection X-ray fluorescence with low power sources coupled to doubly curved crystal optics

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Z.W. [X-ray Optical Systems, Inc. East Greenbush, NY 12061 (United States)]. E-mail: zchen@xos.com; Mail, N. [Center For X-ray Optics, State University of New York, University at Albany (United States); Wei, F.Z. [X-ray Optical Systems, Inc. East Greenbush, NY 12061 (United States); MacDonald, C.A. [Center For X-ray Optics, State University of New York, University at Albany (United States); Gibson, W.M. [X-ray Optical Systems, Inc. East Greenbush, NY 12061 (United States)

    2005-04-30

    A focused beam total X-ray fluorescence technique was developed based on doubly curved crystal optics. This technique provides good detection sensitivity and spatial resolution for localized detection of surface deposits. Compact low power X-ray sources were used to demonstrate the benefit of the X-ray optics for focusing Cr K{alpha}, Cu K{alpha} and Mo K{alpha} radiation. The detection capability of the focused beam Total reflection X-ray fluorescence system was investigated with dried droplets of calibrated low concentration solutions. Detection limits at the femtogram level were demonstrated.

  9. A Radio Monitoring Survey of Ultra-Luminous X-Ray Sources

    CERN Document Server

    Koerding, E; Falcke, H

    2005-01-01

    We present the results of a radio monitoring campaign to search for radio emission from nearby ultra-luminous X-ray sources (ULXs). These sources are bright off-nuclear X-ray point sources with luminosities exceeding L_X > 10^39 erg/sec. A well-defined sample of the 9 nearest ULXs has been monitored eight times during 5 months with the Very Large Array in A and B configuration. Our limiting sensitivity is approximately 0.15 mJy (4 sigma) for radio flares and around 60 uJy for continuous emission. In M82 two ULXs seem to have coincident compact radio sources, which are probably supernova remnants. No continuous or flaring radio emission has been detected from any other ULX. Thus, ULXs do not generally emit steady-state radio emission above radio powers of 1.5 10^17 W/Hz. The non-detections of the continuous emission are consistent with beamed or unbeamed radio emission from accreting black holes of <= 10^3 Msol based on the radio/X-ray correlation. Other published radio detections (M82, NGC 5408) are also d...

  10. Toward a Clean Sample of Ultra-Luminous X-ray Sources

    CERN Document Server

    López-Corredoira, M

    2006-01-01

    CONTEXT. Observational follow-up programmes for the characterization of ultra-luminous X-ray sources (ULXs) require the construction of clean samples of such sources in which the contamination by foreground/background sources is minimum. AIMS. In this article we calculate the degree of foreground/background contaminants among the ULX sample candidates in the Colbert & Ptak (2002) catalogue and compare these computations with available spectroscopical identifications. METHODS. We use statistics based on known densities of X-ray sources and AGN/QSOs selected in the optical. The analysis is done individually for each parent galaxy. The existing identifications of the optical counterparts are compiled from the literature. RESULTS. More than a half of the ULXs, within twice the distance of the major axis of the 25 mag/arcsec$^2$ isophote from RC3 nearby galaxies and with X-ray luminosities $L_X$[2-10 keV] $\\ge 10^{39}$ erg/s, are expected to be high redshift background QSOs. A list of 25 objects (clean sample)...

  11. Bright X-ray source from a laser-driven micro-plasma-waveguide

    CERN Document Server

    Yi, Longqing

    2016-01-01

    Bright tunable x-ray sources have a number of applications in basic science, medicine and industry. The most powerful sources are synchrotrons, where relativistic electrons are circling in giant storage rings. In parallel, compact laser-plasma x-ray sources are being developed. Owing to the rapid progress in laser technology, very high-contrast femtosecond laser pulses of relativistic intensities become available. These pulses allow for interaction with micro-structured solid-density plasma without destroying the structure by parasitic pre-pulses. The high-contrast laser pulses as well as the manufacturing of materials at micro- and nano-scales open a new realm of possibilities for laser interaction with photonic materials at the relativistic intensities. Here we demonstrate, via numerical simulations, that when coupling with a readily available 1.8 Joule laser, a micro-plasma-waveguide (MPW) may serve as a novel compact x-ray source. Electrons are extracted from the walls by the laser field and form a dense ...

  12. Requirements for dynamical differential phase contrast x-ray imaging with a laboratory source

    Science.gov (United States)

    Macindoe, David; Kitchen, Marcus J.; Irvine, Sarah C.; Fouras, Andreas; Morgan, Kaye S.

    2016-12-01

    X-ray phase contrast enables weakly-attenuating structures to be imaged, with bright synchrotron sources adding the ability to capture time sequences and analyse sample dynamics. Here, we describe the translation of dynamical differential phase contrast imaging from the synchrotron to a compact x-ray source, in order to achieve this kind of time sequence imaging in the laboratory. We formulate broadly-applicable set-up guidelines for the single-grid, single-exposure imaging technique using a divergent source, exploring the experimental factors that restrict set-up size, imaging sensitivity and sample size. Experimental images are presented using the single-grid phase contrast technique with a steel attenuation grid and a liquid-metal-jet x-ray source, enabling exposure times as short as 0.5 s for dynamic imaging. Differential phase contrast images were retrieved from phantoms, incorporating noise filtering to improve the low-count images encountered when imaging dynamics using short exposures.

  13. Information about accretion flows from X-ray timing of pulsating sources

    Science.gov (United States)

    Lamb, F. K.; Pines, D.; Shaham, J.

    1976-01-01

    The response was studied of a rotating neutron star to fluctuating torques and it was found that the observed variations in the pulsation periods of the compact X-ray sources Cen X-3 and Her X-1 could be caused by short time scale fluctuations in the accretion torques acting on the neutron stars. The sizes and rates of the required fluctuations are consistent with current accretion models. Such fluctuations can cause period variations either (a) directly, by causing a random walk of the star's angular velocity or (b) indirectly, by exciting a long-period mode of the neutron star, such as the Tkachenko mode of the rotating neutron superfluid. Phenomena in compact X-ray sources and cataclysmic variables which may be caused by fluctuating mass flow rates are also discussed.

  14. Optical studies of the ultraluminous X-ray source NGC1313 X-2

    CERN Document Server

    Liu, J; Miller, J; Kaaret, Philip; Liu, Jifeng; Bregman, Joel; Miller, Jon; Kaaret, Philip

    2007-01-01

    NGC1313 X-2 was among the first ultraluminous X-ray sources discovered, and has been a frequent target of X-ray and optical observations. Using the HST/ACS multi-band observations, this source is identified with a unique counterpart within an error circle of $0\\farcs2$. The counterpart is a blue star on the edge of a young cluster of $\\le10^7$ years amid a dominant old stellar population. Its spectral energy distribution is consistent with that for a Z=0.004 star with 8.5 $M_\\odot$ about $5\\times10^6$ years old, or for an O7 V star at solar metallicity. The counterpart exhibited significant variability of $\\Delta m = 0.153\\pm0.033$ mag between two F555W observations separated by three months, reminiscent of the ellipsoidal variability due to the orbital motion of this ULX binary.

  15. Fast electron slowing-down and diffusion in a high temperature coronal X-ray source

    CERN Document Server

    Galloway, R K; Kontar, E P; Helander, P; Galloway, Ross K.; Kinnon, Alexander L. Mac; Kontar, Eduard P.; Helander, Per

    2005-01-01

    Finite thermal velocity modifications to electron slowing-down rates may be important for the deduction of solar flare total electron energy. Here we treat both slowing-down and velocity diffusion of electrons in the corona at flare temperatures, for the case of a simple, spatially homogeneous source. Including velocity diffusion yields a consistent treatment of both `accelerated' and `thermal' electrons. It also emphasises that one may not invoke finite thermal velocity target effects on electron lifetimes without simultaneously treating the contribution to the observed X-ray spectrum from thermal electrons. We present model calculations of the X-ray spectra resulting from injection of a power-law energy distribution of electrons into a source with finite temperature. Reducing the power-law distribution low-energy cutoff to lower and lower energies only increases the relative magnitude of the thermal component of the spectrum, because the lowest energy electrons simply join the background thermal distributio...

  16. Increasing X-Ray Brightness of HBL Source 1ES 1727+650

    Science.gov (United States)

    Kapanadze, Bidzina

    2017-02-01

    The nearby TeV-detected HBL object 1ES 1727+502 (1Zw 187, z=0.055) has been targeted 111 times by X-ray Telescope (XRT) onboard Swift since 2010 April 2. During this monitoring, the 0.3-10 keV count rate varied by a factor of 17.4 (see http://www.swift.psu.edu/monitoring/source.php?source=QSOB1727+502) and showed a prolonged X-ray flaring activity during 2015 March - 2016 February, revealed mainly via the Target of Opportunity observations performed in the framework of our request of different urgencies (Request Number 6571, 6606, 6717, 6809, 6927, 7322, 7355, 7379, 7390, 7404, 7430, 7441, 7516, 7565; see Kapanadze et al. 2015, Atel #8224, #7342).

  17. A Superbend X-Ray Microdiffraction Beamline at the Advanced Light Source

    Energy Technology Data Exchange (ETDEWEB)

    Tamura, N.; Kunz, M.; Chen, K.; Celestre, R.S.; MacDowell, A.A.; Warwick, T.

    2009-03-10

    Beamline 12.3.2 at the Advanced Light Source is a newly commissioned beamline dedicated to x-ray microdiffraction. It operates in both monochromatic and polychromatic radiation mode. The facility uses a superconducting bending magnet source to deliver an X-ray spectrum ranging from 5 to 22 keV. The beam is focused down to {approx} 1 um size at the sample position using a pair of elliptically bent Kirkpatrick-Baez mirrors enclosed in a vacuum box. The sample placed on high precision stages can be raster-scanned under the microbeam while a diffraction pattern is taken at each step. The arrays of diffraction patterns are then analyzed to derive distribution maps of phases, strain/stress and/or plastic deformation inside the sample.

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

    Energy Technology Data Exchange (ETDEWEB)

    Gmuer, N.F.; White-DePace, S.M. (eds.)

    1987-08-01

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

  19. Source assemblage types for cratonic diamonds from X-ray synchrotron diffraction

    Science.gov (United States)

    Nestola, F.; Alvaro, M.; Casati, M. N.; Wilhelm, H.; Kleppe, A. K.; Jephcoat, A. P.; Domeneghetti, M. C.; Harris, J. W.

    2016-11-01

    Three single crystals of clinopyroxene trapped within three different gem-quality diamonds from the Udachnaya kimberlite (Siberia, Russia) were analysed in situ by single-crystal synchrotron X-ray diffraction in order to obtain information on their chemical composition and infer source assemblage type. A non-destructive approach was used with high-energy (≈ 60 keV; λ ≈ 0.206 Å) at I15, the extreme-conditions beamline at Diamond Light Source. A dedicated protocol was used to center the mineral inclusions located deep inside the diamonds in the X-ray beam. Our results reveal that two of the inclusions can be associated with peridotitic paragenesis whereas the third is eclogitic. This study also demonstrates that this non-destructive experimental approach is extremely efficient in evaluating the origin of minerals trapped in their diamond hosts.

  20. MIT modular x-ray source systems for the study of plasma diagnostics

    Science.gov (United States)

    Coleman, J. W.; Wenzel, K. W.; Petrasso, R. D.; Lo, D. H.; Li, C. K.; Lierzer, J. R.; Wei, T.

    1992-10-01

    Two new x-ray source systems are now on line at our facility. Each provides an e-beam to 25 kV. Targets are interchangeable between machines, and four x-ray detectors may be used simultaneously with a target. The gridded e-gun of the RACEHORSE system gives a 0.5-1.0-cm pulsable spot on target. The nongridded e-gun of the SCORPION system provides a 0.3-mm or smaller dc microspot on target. RACEHORSE is being used to study and characterize type-II diamond photoconductors for use in diagnosing plasmas, while SCORPION is being used to develop a slitless spectrograph using photographic film. Source design details and some RACEHORSE results are presented.

  1. Constraining High Redshift X-ray Sources with Next Generation 21 cm Power Spectrum Measurements

    CERN Document Server

    Ewall-Wice, Aaron; Mesinger, Andrei; Dillon, Joshua S; Liu, Adrian; Pober, Jonathan

    2015-01-01

    We use the Fisher matrix formalism and semi-numerical simulations to derive quantitative predictions of the constraints that power spectrum measurements on next-generation interferometers, such as the Hydrogen Epoch of Reionization Array (HERA) and the Square Kilometre Array (SKA), will place on the characteristics of the X-ray sources that heated the high redshift intergalactic medium. Incorporating observations between $z=5$ and $z=25$, we find that the proposed 331 element HERA and SKA phase 1 will be capable of placing $\\lesssim 10\\%$ constraints on the spectral properties of these first X-ray sources, even if one is unable to perform measurements within the foreground contaminated "wedge" or the FM band. When accounting for the enhancement in power spectrum amplitude from spin temperature fluctuations, we find that the observable signatures of reionization extend well beyond the peak in the power spectrum usually associated with it. We also find that lower redshift degeneracies between the signatures of ...

  2. The Broadband XMM-Newton and NuSTAR X-Ray Spectra of Two Ultraluminous X-Ray Sources in the Galaxy IC 342

    Science.gov (United States)

    Rana, Vikram; Harrison, Fiona A.; Bachetti, Matteo; Walton, Dominic J.; Furst, Felix; Barret, Didier; Miller, Jon M.; Fabian, Andrew C.; Boggs, Steven E.; Christensen, Finn C.; Craig, William W.; Grefenstette, Brian W.; Hailey, Charles J.; Madsen, Kristin K.; Ptak, Andrew F.; Stern, Daniel; Webb, Natalie A.; Zhang, William W.

    2015-02-01

    We present results for two ultraluminous X-ray sources (ULXs), IC 342 X-1 and IC 342 X-2, using two epochs of XMM-Newton and NuSTAR observations separated by ~7 days. We observe little spectral or flux variability above 1 keV between epochs, with unabsorbed 0.3-30 keV luminosities being 1.04+0.08-0.06 × 1040 erg s-1 for IC 342 X-1 and 7.40 ± 0.20 × 1039 erg s-1 for IC 342 X-2, so that both were observed in a similar, luminous state. Both sources have a high absorbing column in excess of the Galactic value. Neither source has a spectrum consistent with a black hole binary in low/hard state, and both ULXs exhibit strong curvature in their broadband X-ray spectra. This curvature rules out models that invoke a simple reflection-dominated spectrum with a broadened iron line and no cutoff in the illuminating power-law continuum. X-ray spectrum of IC 342 X-1 can be characterized by a soft disk-like blackbody component at low energies and a cool, optically thick Comptonization continuum at high energies, but unique physical interpretation of the spectral components remains challenging. The broadband spectrum of IC 342 X-2 can be fit by either a hot (3.8 keV) accretion disk or a Comptonized continuum with no indication of a seed photon population. Although the seed photon component may be masked by soft excess emission unlikely to be associated with the binary system, combined with the high absorption column, it is more plausible that the broadband X-ray emission arises from a simple thin blackbody disk component. Secure identification of the origin of the spectral components in these sources will likely require broadband spectral variability studies.

  3. Stellar-mass black holes and ultraluminous x-ray sources.

    Science.gov (United States)

    Fender, Rob; Belloni, Tomaso

    2012-08-03

    We review the likely population, observational properties, and broad implications of stellar-mass black holes and ultraluminous x-ray sources. We focus on the clear empirical rules connecting accretion and outflow that have been established for stellar-mass black holes in binary systems in the past decade and a half. These patterns of behavior are probably the keys that will allow us to understand black hole feedback on the largest scales over cosmological time scales.

  4. Energy-dispersive X-ray diffraction beamline at Indus-2 synchrotron source

    Indian Academy of Sciences (India)

    K K Pandey; H K Poswal; A K Mishra; Abhilash Dwivedi; R Vasanthi; Nandini Garg; Surinder M Sharma

    2013-04-01

    An energy-dispersive X-ray diffraction beamline has been designed, developed and commissioned at BL-11 bending magnet port of the Indian synchrotron source, Indus-2. The performance of this beamline has been benchmarked by measuring diffraction patterns from various elemental metals and standard inorganic powdered samples. A few recent high-pressure investigations are presented to demonstrate the capabilities of the beamline.

  5. Swift follow-up of unidentified X-ray sources in the XMM-Newton Slew Survey

    OpenAIRE

    Starling, R. L. C.; Evans, P. A.; Read, A. M.; Saxton, R. D.; Esquej, P.; Krimm, H.; O'Brien, P.T.; Osborne, J. P.; Mateos, S.; Warwick, R.; Wiersema, K.

    2010-01-01

    We present deep Swift follow-up observations of a sample of 94 unidentified X-ray sources from the XMM-Newton Slew Survey. The X-ray Telescope on-board Swift detected 29% of the sample sources; the flux limits for undetected sources suggests the bulk of the Slew Survey sources are drawn from one or more transient populations. We report revised X-ray positions for the XRT-detected sources, with typical uncertainties of 2.9", reducing the number of catalogued optical matches to just a single so...

  6. The Broadband XMM-Newton and NuSTAR X-ray Spectra of Two Ultraluminous X-ray Sources in the Galaxy IC 342

    DEFF Research Database (Denmark)

    Rana, Vikram; Harrison, Fiona A.; Bachetti, Matteo

    2015-01-01

    We present results for two Ultraluminous X-ray Sources (ULXs), IC 342 X-1 and IC 342 X-2, using two epochs of XMM-Newton and NuSTAR observations separated by ∼7 days. We observe little spectral or flux variability above 1 keV between epochs, with unabsorbed 0.3-30 keV luminosities being $1.......04+0.08/-0.06 x 1040 erg s-1 for IC 342 X-1 and 7.40±0.20 x 1039 erg s-1for IC 342 X-2, so that both were observed in a similar, luminous state. Both sources have a high absorbing column in excess of the Galactic value. Neither source has a spectrum consistent with a black hole binary in low/hard state, and both...... ULXs exhibit strong curvature in their broadband X-ray spectra. This curvature rules out models that invoke a simple reflection-dominated spectrum with a broadened iron line and no cutoff in the illuminating power-law continuum. X-ray spectrum of IC 342 X-1 can be characterized by a soft disk...

  7. The XXL Survey: VI. The 1000 brightest X-ray point sources

    CERN Document Server

    Fotopoulou, S; Paltani, S; Ranalli, P; Ramos-Ceja, M E; Faccioli, L; Plionis, M; Adami, C; Bongiorno, A; Brusa, M; Chiappetti, L; Desai, S; Elyiv, A; Lidman, C; Melnyk, O; Pierre, M; Piconcelli, E; Vignali, C; Alis, S; Ardila, F; Arnouts, S; Baldry, I; Bremer, M; Eckert, D; Guennou, L; Horellou, C; Iovino, A; Koulouridis, E; Liske, J; Maurogordato, S; Menanteau, F; Mohr, J J; Owers, M; Poggianti, B; Pompei, E; Sadibekova, T; Stanford, A; Tuffs, R; Willis, J

    2016-01-01

    X-ray extragalactic surveys are ideal laboratories for the study of the evolution and clustering of active galactic nuclei (AGN). The XXL Survey spans two fields of a combined 50 $deg^2$ observed for more than 6Ms with XMM-Newton, occupying the parameter space between deep surveys and very wide area surveys; at the same time it benefits from a wealth of ancillary data. This paper marks the first release of the XXL point source catalogue selected in the 2-10 keV energy band with limiting flux $F_{2-10keV}=4.8\\cdot10^{-14}\\rm{erg\\,s^{-1}\\,cm^{-2}}$. We use both public and proprietary data sets to identify the counterparts of the X-ray point-like sources and improved upon the photometric redshift determination for AGN by applying a Random Forest classification trained to identify for each object the optimal photometric redshift model library. We also assign a probability to each source to be a star or an outlier. We model with Bayesian analysis the X-ray spectra assuming a power-law model with the presence of an...

  8. The Ultraluminous X-ray Sources near the Center of M82

    CERN Document Server

    Kong, A K H; Hsieh, P -Y; Mak, D S Y; Pun, C S J

    2007-01-01

    We report the discovery of a recurrent ultraluminous X-ray source(ULX), a background AGN, and a young supernova remnant near the center of the starburst galaxy M82. From a series of Chandra observations taken from 1999 to 2005, we found that the ULX first appeared in 1999 October. The source turned off in 2000 January, but later reappeared and has been active since then. The X-ray luminosity of this source varies from below the detection level (~ 2.5e38 erg/s) to its active state in between ~8e39 erg/s and 1.3e40 erg/s (in the 0.5-10 keV energy band) and shows unusual spectral changes. The X-ray spectra are best fitted with an absorbed power-law model with photon index ranging from 1.3 to 1.7. The spectra are similar to those Galactic black hole binary candidates seen in the low/hard state except that a very hard spectrum was seen in one of the observations. By comparing with near infrared images taken with the Hubble Space Telescope, the ULX is found to be located within a young star cluster. Radio imaging i...

  9. Narrow Line X-Ray Calibration Source for High Resolution Microcalorimeters

    Science.gov (United States)

    Hokin, M.S.; McCammon, D.; Morgan, K.M.; Bandler, Simon Richard; Lee, S.J.; Moseley, S.H.; Smith, S.J.

    2013-01-01

    We are developing a narrow line calibration source for use with X-ray microcalorimeters. At energies below 300 electronvolts fluorescent lines are intrinsically broad, making calibration of high resolution detectors difficult. This source consists of a 405 nanometers (3 electronvolts) laser diode coupled to an optical fiber. The diode is pulsed to create approximately one hundred photons in a few microseconds. If the pulses are short compared to the rise time of the detector, they will be detected as single events with a total energy in the soft X-ray range. Poisson fluctuations in photon number per pulse create a comb of X-ray lines with 3 electronvolts spacing, so detectors with energy resolution better than 2 electronvolts are required to resolve the individual lines. Our currently unstabilized diode has a multimode width less than 1 nanometer, giving a 300 electronvolt event a Full width at half maximum (FWHM) less than 0.1 electronvolts. By varying the driving voltage, or pulse width, the source can produce a comb centered on a wide range of energies. The calibration events are produced at precisely known times. This allows continuous calibration of a flight mission without contaminating the observed spectrum and with minimal deadtime.

  10. 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)

  11. Kilohertz sources of hard x rays and fast ions with femtosecond laser plasmas

    Science.gov (United States)

    Thoss, A.; Richardson, M.; Korn, G.; Faubel, M.; Stiel, H.; Vogt, U.; Elsaesser, T.

    2003-01-01

    We demonstrate a new, stable, kilohertz femtosecond laser plasma source of hard-x-ray continuum and Kα emission that uses a microscopic liquid jet target that is continuous and debris free. Plasmas produced by ultrashort (50-fs) intense laser pulses from a fine (10-30-μm diameter) liquid Ga jet emit bright 9.3- and 10.3-keV Kα and Kβ lines superimposed on a multikilovolt bremmstrahlung continuum. Kilohertz 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 debris free. Our target provides a pristine, unperturbed filament surface at rates >100 kHz. A number of liquid metal targets are considered. We show the hard-x-ray spectrum described above. The source was generated by a 50-fs-duration, 1-kHz, 2-W, high-intensity Ti:sapphire laser. Using the same technology, we also generate forward-going sub-mega-electron-volt (sub-MeV) protons from a 10-μm liquid water target at 1-kHz repetition rates. Kilohertz sources of high-energy ions will find many applications in time-resolved particle interaction studies and will lead to efficient generation of short-lived isotopes for use in nuclear medicine and other applications. The protons were detected with CR-39 track detectors in both the forward and the backward directions up to energies of ~500 keV. As the intensity of compact high-repetition-rate lasers sources increases, we can expect improvements in the energy, conversion efficiency, and directionality to occur. The effect of these developments is discussed. As compact, high-repetition-rate femtosecond laser technology reaches focused intensities of ~1019 W/cm2, many new applications of high-repetition-rate hard-x-ray and MeV ion sources will become practical.

  12. Broadband X-ray Spectra of the Ultraluminoux X-ray Source Holmberg IX X-1 observed with NuSTAR, XMM-Newton and Suzaku

    CERN Document Server

    Walton, D J; Grefenstette, B W; Miller, J M; Bachetti, M; Barret, D; Boggs, S E; Christensen, F E; Craig, W W; Fabian, A C; Fuerst, F; Hailey, C J; Madsen, K K; Parker, M L; Ptak, A; Rana, V; Stern, D; Webb, N A; Zhang, W W

    2014-01-01

    We present results from the coordinated broadband X-ray observations of the extreme ultraluminous X-ray source Holmberg IX X-1 performed by NuSTAR, XMM-Newton and Suzaku in late 2012. These observations provide the first high-quality spectra of Holmberg IX X-1 above 10 keV to date, extending the X-ray coverage of this remarkable source up to ~30 keV. Broadband observations were undertaken at two epochs, between which Holmberg IX X-1 exhibited both flux and strong spectral variability, increasing in luminosity from Lx = (1.94+/-0.03)e40 erg/s to Lx = (3.38+/-0.03)e40 erg/s. Neither epoch exhibits a spectrum consistent with emission from the standard low/hard accretion state seen in Galactic black hole binaries, that would have been expected if Holmberg IX X-1 harbors a truly massive black hole accreting at substantially sub-Eddington accretion rates. The NuSTAR data confirm that the curvature observed previously in the 3-10 keV bandpass does represent a true spectral cutoff. During each epoch, the spectrum app...

  13. Is the Variable X-ray Source in M82 due to Gravitational Lensing?

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    We explore the possibility of attributing the recent discovery of the variable hard X-ray source CXO M82 J095550.2+694047 in M82 to the gravitational magnification by an intervening stellar object along the line of sight acting as a mi-crolens. The duration of the event (> 84 days) allows us to set robust constraints on the mass and location of the microlensing object when combined with the dynam-ical properties of the Galactic halo, M82 and typical globular clusters. Except for the extremely low probability, the microlensing magnification by MACHO in either the Galactic halo or M82 halo is able to explain the X-ray variability of CXO M82 J095550.2+694047. It is hoped that the lensing hypothesis can be tested soon by measurement of the light curve.

  14. XMM-Newton EPIC observations of the ultraluminous X-ray source NGC 5204 X-1

    CERN Document Server

    Roberts, T P; Ward, M J; Goad, M R; Jenkins, L P

    2004-01-01

    We present the results of two XMM-Newton observations of the ultraluminous X-ray source (ULX) NGC 5204 X-1. The EPIC spectra are well-fit by the standard spectral model of a black-hole X-ray binary, comprising a soft multi-colour disc blackbody component plus a harder power-law continuum. The cool (kT_in ~ 0.2 keV) inner-disc temperature required by this model favours the presence of an intermediate-mass black hole (IMBH) in this system, though we highlight a possible anomaly in the slope of the power-law continuum in such fits. We discuss the interpretation of this and other, non-standard spectral modelling of the data.

  15. Electron Beam Production and Characterization for the PLEIADES Thomson X-ray Source

    Energy Technology Data Exchange (ETDEWEB)

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

    2002-10-14

    We report on the performance of an S-band RF photocathode electron gun and accelerator for operation with the PLEIADES Thomson x-ray source at LLNL. Simulations of beam production, transport, and focus are presented. It is shown that a 1 ps, 500 pC electron bunch with a normalized emittance of less than 5 {pi}mm-mrad can be delivered to the interaction point. Initial electron measurements are presented. Calculations of expected x-ray flux are also performed, demonstrating an expected peak spectral brightness of 10{sup 20} photons/s/mm{sup 2}/mrad{sup 2}/0.1% bandwidth. Effects of RF phase jitter are also presented, and planned phase measurements and control methods are discussed.

  16. Estimates of Imaging Times for Conventional and Synchrotron X-Ray Sources

    CERN Document Server

    Kinney, J

    2003-01-01

    The following notes are to be taken as estimates of the time requirements for imaging NIF targets in three-dimensions with absorption contrast. The estimates ignore target geometry and detector inefficiency, and focus only on the statistical question of detecting compositional (structural) differences between adjacent volume elements in the presence of noise. The basic equations, from the classic reference by Grodzins, consider imaging times in terms of the required number of photons necessary to provide an image with given resolution and noise. The time estimates, therefore, have been based on the calculated x-ray fluxes from the proposed Advanced Light Source (ALS) imaging beamline, and from the calculated flux for a tungsten anode x-ray generator operated in a point focus mode.

  17. Femtosecond powder diffraction with a laser-driven hard X-ray source.

    Science.gov (United States)

    Zamponi, F; Ansari, Z; Woerner, M; Elsaesser, T

    2010-01-18

    X-ray powder diffraction with a femtosecond time resolution is introduced to map ultrafast structural dynamics of polycrystalline condensed matter. Our pump-probe approach is based on photoexcitation of a powder sample with a femtosecond optical pulse and probing changes of its structure by diffracting a hard X-ray pulse generated in a laser-driven plasma source. We discuss the key aspects of this scheme including an analysis of detection sensitivity and angular resolution. Applying this technique to the prototype molecular material ammonium sulfate, up to 20 powder diffraction rings are recorded simultaneously with a time resolution of 100 fs. We describe how to derive transient charge density maps of the material from the extensive set of diffraction data in a quantitative way.

  18. Intense X-ray sources based on compton scattering in laser electron storage rings

    CERN Document Server

    Gladkikh, P I; Karnaukhov, I M

    2002-01-01

    The main problem of the designing of intense X-ray sources based on Compton scattering in laser-electron storage ring is associated with large steady-state electron beam energy spread. In paper the principles of the development of compact storage ring lattice with large RF-acceptance and negligible chromatic effects at interaction point are considered. The storage ring with electron beam energy over the range 100-400 MeV that allows generating intense VUV from bending magnets, X-ray up to 280 keV with rate up to 10 sup 1 sup 4 photons/s and gamma-beam up to 2.8 MeV for neutron generation on beryllium target is proposed.

  19. A jet model for Galactic black-hole X-ray sources: Some constraining correlations

    CERN Document Server

    Kylafis, N D; Reig, P; Giannios, D; Pooley, G G

    2008-01-01

    Some recent observational results impose significant constraints on all the models that have been proposed to explain the Galactic black-hole X-ray sources in the hard state. In particular, it has been found that during the hard state of Cyg X-1 the power-law photon number spectral index is correlated with the average time lag between hard and soft X-rays. Furthermore, the peak frequencies of the four Lorentzians that fit the observed power spectra are correlated with both the photon index and the time lag. We performed Monte Carlo simulations of Compton upscattering of soft, accretion-disk photons in the jet and computed the time lag between hard and soft photons and the power-law index of the resulting photon number spectra. We demonstrate that our jet model naturally explains the above correlations, with no additional requirements and no additional parameters.

  20. Recent Measurements And Plans for the SLAC Compton X-Ray Source

    Energy Technology Data Exchange (ETDEWEB)

    Vlieks, A.E.; Akre, R.; Caryotakis, G.; DeStefano, C.; Frederick, W.J.; Heritage, J.P.; Luhmann, N.C.; Martin, D.; Pellegrini, C.; /SLAC /UC, Davis /UCLA

    2006-02-14

    A compact source of monoenergetic X-rays, generated via Compton backscattering, has been developed in a collaboration between U.C Davis and SLAC. The source consists of a 5.5 cell X-band photoinjector, a 1.05 m long high gradient accelerator structure and an interaction chamber where a high power (TW), short pulse (sub-ps) infrared laser beam is brought into a nearly head-on collision with a high quality focused electron beam. Successful completion of this project will result in the capability of generating a monoenergetic X-ray beam, continuously tunable from 20 - 85 keV. We have completed a series of measurements leading up to the generation of monoenergetic X-rays. Measurements of essential electron beam parameters and the techniques used in establishing electron/photon collisions will be presented. We discuss the design of an improved interaction chamber, future electro-optic experiments using this chamber and plans for expanding the overall program to the generation of Terahertz radiation.

  1. Demonstration of a non-contact x-ray source using an inductively heated pyroelectric accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Klopfer, Michael; Satchouk, Vladimir; Cao, Anh; Wolowiec, Thomas; Alivov, Yahya; Molloi, Sabee, E-mail: symolloi@uci.edu

    2015-04-11

    X-ray emission from pyroelectric sources can be produced through non-contact thermal cycling using induction heating. In this study, we demonstrated a proof of concept non-contact x-ray source powered via induction heating. An induction heater operating at 62.5 kHz provided a total of 6.5 W of delivered peak thermal power with 140 V DC of driving voltage. The heat was applied to a ferrous substrate mechanically coupled to a cubic 1 cm{sup 3} Lithium Niobate (LiNbO{sub 3}) pyroelectric crystal maintained in a 3–12 mTorr vacuum. The maximum temperature reached was 175 °C in 86 s of heating. The cooling cycle began immediately after heating and was provided by passive radiative cooling. The total combined cycle time was 250 s. x-ray photons were produced and analyzed in both heating and cooling phases. Maximum photon energies of 59 keV and 55 keV were observed during heating and cooling, respectively. Non-contact devices such as this, may find applications in cancer therapy (brachytherapy), non-destructive testing, medical imaging, and physics education fields.

  2. Discovery of coherent pulsations from the Ultraluminous X-ray Source NGC 7793 P13

    CERN Document Server

    Fuerst, F; Harrison, F A; Stern, D; Barret, D; Brightman, M; Fabian, A C; Madsen, K K; Middleton, M J; Miller, J M; Pottschmidt, K; Ptak, A; Rana, V

    2016-01-01

    We report the detection of coherent pulsations from the ultraluminous X-ray source NGC 7793 P13. The ~0.42s nearly sinusoidal pulsations were initially discovered in broadband X-ray observations using XMM-Newton and NuSTAR taken in 2016. We subsequently also found pulsations in archival XMM-Newton data taken in 2013 and 2014. The significant (>>5 sigma) detection of coherent pulsations demonstrates that the compact object in P13 is a neutron star with an observed peak luminosity of ~1e40 erg/s, well above the Eddington limit for a 1.4 M_sun accretor. This makes P13 the second ultraluminous X-ray source known to be powered by an accreting neutron star. The pulse period varies between epochs, with a slow but persistent spin up over the 2013-2016 period. This spin-up indicates a magnetic field of B ~ 1.5e12 G, typical of many accreting pulsars. The most likely explanation for the extreme luminosity is a high degree of beaming, however this is difficult to reconcile with the sinusoidal pulse profile.

  3. Focusing performance and thermal property of carbon-nanotube emitter-based X-ray sources

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Ho; Kim, Wan Sun; Ryu, Je Hwang; Kim, Kyung Sook; Park, Hun Kuk [Kyung Hee University, Seoul (Korea, Republic of)

    2014-12-15

    Carbon-nanotube (CNT) emitter-based X-ray sources have been extensively investigated as new imaging devices. The electron-beam trajectory in the CNT emitter-based X-ray sources were simulated to determine the optimized conditions for high focusing performance and limited thermal damage to the anode. The beam trajectory from the cathode to the anode was simulated, and the focal spot size (FSS) of the beam was determined by varying the structure of the electrode in the X-ray system. The temperature change of the anode caused by the electron-beam was calculated. The effects of electrode voltage and of the distance between the electrode and the anode on the FSS were significant while the effect of electrode thickness was small in all structures. When the electron-beam was emitted with an FSS of 170 μm and a power of 130 W, the thermal damage to the anode was reduced by using a 2-ms pulsed-voltage operation for a duration of 8 ms.

  4. The Chandra Cygnus OB2 Legacy Survey: Design and X-ray Point Source Catalog

    CERN Document Server

    Wright, Nicholas J; Guarcello, Mario G; Aldcroft, Tom L; Kashyap, Vinay L; Damiani, Francesco; DePasquale, Joe; Fruscione, Antonella

    2014-01-01

    The Cygnus OB2 association is the largest concentration of young and massive stars within 2 kpc of the Sun, including an estimated 65 O-type stars and hundreds of OB stars. The Chandra Cygnus OB2 Legacy Survey is a large imaging program undertaken with the Advanced CCD Imaging Spectrometer onboard the Chandra X-ray Observatory. The survey has imaged the central 0.5 deg^2 of the Cyg OB2 association with an effective exposure of 120ks and an outer 0.35 deg^2 area with an exposure of 60ks. Here we describe the survey design and observations, the data reduction and source detection, and present a catalog of 8,000 X-ray point sources. The survey design employs a grid of 36 heavily (~50%) overlapping pointings, a method that overcomes Chandra's low off-axis sensitivity and produces a highly uniform exposure over the inner 0.5 deg^2. The full X-ray catalog is described here and is made available online.

  5. A Flaring X-ray Source with an Halpha-bright Counterpart toward the SMC

    CERN Document Server

    Laycock, Silas

    2008-01-01

    We report the discovery of a flaring X-ray source with an optical counterpart with Halpha emission and red-excess, in the direction of the SMC. A 100 ksec X-ray observation with Chandra detected a flare lasting 6 ksec in the source CXO J005428.9-723107. The X-ray spectrum during the flare was consistent with a thermal plasma of temperature kT=2.5 keV. In quiescence following the flare the spectrum was softer (kT= 0.4 keV). Timing analysis did not reveal any significant periodicities or QPOs. Optical images taken with the Magellan-Baade 6.5m telescope show a single star in the (0.9") error circle. This star has apparent magnitude V=19.17, exhibits enhanced Halpha emission (Halpha - r = -0.88), and has a large proper motion. Alternative explanations are explored, leading to identification as a relatively nearby (Galactic) coronally active star of the BY Draconis class.

  6. Operation of a picosecond narrow-bandwidth Laser–Thomson-backscattering X-ray source

    Energy Technology Data Exchange (ETDEWEB)

    Jochmann, A., E-mail: a.jochmann@hzdr.de [Helmholtz-Zentrum Dresden-Rossendorf e.V., D-01328 Dresden (Germany); Irman, A.; Lehnert, U.; Couperus, J.P.; Kuntzsch, M. [Helmholtz-Zentrum Dresden-Rossendorf e.V., D-01328 Dresden (Germany); Trotsenko, S. [Helmholtz-Institut Jena, Friedrich Schiller Universität Jena, D-07743 Jena (Germany); Wagner, A.; Debus, A.D.; Schlenvoigt, H.-P.; Helbig, U.; Bock, S. [Helmholtz-Zentrum Dresden-Rossendorf e.V., D-01328 Dresden (Germany); Ledingham, K.W.D. [SUPA, Strathclyde University Glasgow, UK-07743 Glasgow (United Kingdom); Cowan, T.E.; Sauerbrey, R.; Schramm, U. [Helmholtz-Zentrum Dresden-Rossendorf e.V., D-01328 Dresden (Germany)

    2013-08-15

    A tunable source of intense ultra-short hard X-ray pulses represents a novel tool for the structural analysis of complex systems with unprecedented temporal and spatial resolution. With the simultaneous availability of a high power short-pulse laser system this provides unique opportunities at the forefront of relativistic light–matter interactions. At Helmholtz-Zentrum Dresden-Rossendorf (HZDR) we demonstrated the principle of such a light source (PHOENIX – Photon Electron collider for Narrow bandwidth Intense X-Rays) by colliding picosecond electron bunches from the ELBE linear accelerator with counter-propagating femtosecond laser pulses from the 150 TW Draco Ti:Sapphire laser system. The generated narrowband X-rays are highly collimated and can be reliably adjusted from 12 keV to 20 keV by tuning the electron energy (24–30 MeV). Ensuring the spatial–temporal overlap at the interaction point and suppressing the Bremsstrahlung background a signal to noise ratio of greater than 300 was reached.

  7. High intensity compact Compton X-ray sources: Challenges and potential of applications

    Energy Technology Data Exchange (ETDEWEB)

    Jacquet, M., E-mail: mjacquet@lal.in2p3.fr

    2014-07-15

    Thanks to the exceptional development of high power femtosecond lasers in the last 15 years, Compton based X-ray sources are in full development over the world in the recent years. Compact Compton sources are able to combine the compactness of the instrument with a beam of high intensity, high quality, tunable in energy. In various fields of applications such as biomedical science, cultural heritage preservation and material science researches, these sources should provide an easy working environment and the methods currently used at synchrotrons could be largely developed in a lab-size environment as hospitals, labs, or museums.

  8. A laser-driven undulator x-ray source: simulation of image formation and dose deposition in mammography

    Science.gov (United States)

    Müller, Bernhard; Schlattl, Helmut; Grüner, Florian; Hoeschen, Christoph

    2011-03-01

    Since overcoming some of the inherent limitations of x-ray tubes becomes increasingly harder, it is important to consider new ways of x-ray generation and to study their applications in the field of medical imaging. In the present work we investigate a novel table-top-sized x-ray source, developed in a joint project within the Cluster of Excellence "Munich Center for Advanced Photonics". It uses laser-accelerated electrons emitting x-ray radiation in a short period undulator. This source has the potential to deliver tunable x-rays with a very narrow spectral bandwidth. The main purpose of this contribution is to investigate the performance of this source in the field of mammography and to compare it to that of conventional x-ray tubes. We simulated the whole imaging process from the electron beam dynamics through the generation of the synchrotron radiation in the undulator up to the x-ray-matter interaction and detection in the mammographic setting. A Monte Carlo simulation of the absorption and scattering processes based on the Geant4 software toolkit has been developed that uses a high-resolution voxel phantom of the female breast for the accurate simulation of mammography. We present simulated mammograms generated by using quasi-monochromatic undulator radiation and by using the polychromatic spectrum of a conventional x-ray tube.

  9. CXO J004318.8+412016, a steady supersoft X-ray source in M 31

    Science.gov (United States)

    Orio, Marina; Luna, G. J. M.; Kotulla, R.; Gallager, J. S.; Zampieri, L.; Mikolajewska, J.; Harbeck, D.; Bianchini, A.; Chiosi, E.; Della Valle, M.; de Martino, D.; Kaur, A.; Mapelli, M.; Munari, U.; Odendaal, A.; Trinchieri, G.; Wade, J.; Zemko, P.

    2017-09-01

    We obtained an optical spectrum of a star we identify as the optical counterpart of the M31 Chandra source CXO J004318.8+412016, because of prominent emission lines of the Balmer series, of neutral helium, and a He II line at 4686 Å. The continuum energy distribution and the spectral characteristics demonstrate the presence of a red giant of K or earlier spectral type, so we concluded that the binary is likely to be a symbiotic system. CXO J004318.8+412016 has been observed in X-rays as a luminous supersoft source (SSS) since 1979, with effective temperature exceeding 40 eV and variable X-ray luminosity, oscillating between a few times 1035 erg s-1 and a few times 1037 erg s-1 in the space of a few weeks. The optical, infrared and ultraviolet colours of the optical object are consistent with an an accretion disc around a compact object companion, which may be either a white dwarf or a black hole, depending on the system parameters. If the origin of the luminous supersoft X-rays is the atmosphere of a white dwarf that is burning hydrogen in shell, it is as hot and luminous as post-thermonuclear flash novae, yet no major optical outburst has ever been observed, suggesting that the white dwarf is very massive (m ≥ 1.2 M⊙) and it is accreting and burning at the high rate \\dot{m} > 10^{-8} M⊙ yr-1 expected for Type Ia supernovae progenitors. In this case, the X-ray variability may be due to a very short recurrence time of only mildly degenerate thermonuclear flashes.

  10. Analyzer-based phase-contrast imaging system using a micro focus x-ray source

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Wei [BME Department, Illinois Institute of Technology, Chicago, Illinois 60616 (United States); Majidi, Keivan; Brankov, Jovan G., E-mail: brankov@iit.edu [ECE Department, Illinois Institute of Technology, Chicago, Illinois 60616 (United States)

    2014-08-15

    Here we describe a new in-laboratory analyzer based phase contrast-imaging (ABI) instrument using a conventional X-ray tube source (CXS) aimed at bio-medical imaging applications. Phase contrast-imaging allows visualization of soft tissue details usually obscured in conventional X-ray imaging. The ABI system design and major features are described in detail. The key advantage of the presented system, over the few existing CXS ABI systems, is that it does not require high precision components, i.e., CXS, X-ray detector, and electro-mechanical components. To overcome a main problem introduced by these components, identified as temperature stability, the system components are kept at a constant temperature inside of three enclosures, thus minimizing the electrical and mechanical thermal drifts. This is achieved by using thermoelectric (Peltier) cooling/heating modules that are easy to control precisely. For CXS we utilized a microfocus X-ray source with tungsten (W) anode material. In addition the proposed system eliminates tungsten's multiple spectral lines by selecting monochromator crystal size appropriately therefore eliminating need for the costly mismatched, two-crystal monochromator. The system imaging was fine-tuned for tungsten Kα{sub 1} line with the energy of 59.3 keV since it has been shown to be of great clinical significance by a number of researchers at synchrotron facilities. In this way a laboratory system that can be used for evaluating and quantifying tissue properties, initially explored at synchrotron facilities, would be of great interest to a larger research community. To demonstrate the imaging capability of our instrument we use a chicken thigh tissue sample.

  11. A Compact X-ray Source in the Radio PWN G141.2+5.0

    Science.gov (United States)

    Reynolds, Stephen P.; Borkowski, Kazimierz J.

    2015-08-01

    We report the results of a 50 ks Chandra observation of the recently discovered radio object G141.2+5.0, presumed to be a pulsar-wind nebula (PWN) (Kothes et al. 2014). We find a faint unresolved X-ray source coincident with the central peak of radio emission. Spectral fits to the 241 counts show that an absorbed power-law describes the data well, with absorbing column NH = 4.8 (2.6, 7.3) x 1021 cm-2 and photon index Γ = 1.6 (1.2, 2.1). (A black-body fit is slightly less favored statistically, and has an implausibly high temperature, kT = 0.9 keV.) For a distance of 4 kpc, the unabsorbed luminosity between 0.5 and 8 keV is 1.8 (1.1, 3.0) x 1032 erg s-1. No extended emission is seen; a very conservative upper limit to Lx (nebula) is about the same luminosity as that observed from the point source. The radio luminosity is about 3 x 1030 erg s-1 the X-ray upper limit then gives Lx/Lr < 700, satisfied by almost all pulsar-wind nebulae. Both Lx and Γ are quite typical of pulsars in PWNe. The steep radio spectrum (α ~ -0.7), if continued to the X-ray without a break, predicts Lx (nebula) ~ 1 x 1033 erg s-1, so additional spectral steepening between radio and X-rays is required, as is true of all known PWNe. The high Galactic latitude gives a z-distance of 350 pc above the Galactic plane, quite unusual for a Population I object.

  12. Effect of Viewing Angle on Super-Soft-Source X-Ray Spectra

    Science.gov (United States)

    Ness, Jan-Uwe

    2012-09-01

    The advent of the X-ray grating spectrometers has given new momentum to the studies of Super-Soft-Source (SSS) X-ray spectra in high resolution. Earlier CCD-type spectra only allow determinations of effective temperatures while in the grating spectra, lines and continuum can be resolved. I have studied the X-ray grating spectra of eight classical novae during their SSS phase, two of them candidates for recurrent novae, two established recurrent novae, and four permanent SSSs including the prototypes Cal 83 and Cal 87. I discovered two categories of SSSs: those dominated by emission lines (SSSe) and by absorption line (SSSa). All spectra contain photospheric continuum emission, indicated by the shape of a blackbody. For the majority of SSSe, the inclination angle is known, which are all greater than 75 degrees. I argue that the SSSe are high-inclination systems in which photospheric X-ray emission from the central source is partially blocked and scattered via Thompson scattering, which preserves the spectral shape of the continuum. Since the electrons in the scattering medium move at high velocities, photospheric absorption lines are smeared out and are therefore not seen. Additional emission lines are produced by resonant line scattering. The fact that only high inclination systems show these effects of scattering, the scattering material must be concentrated to the ecliptic plane. While in permanent SSSs, the accretion disk can explain this behavior, this result implies that in novae, the reformation of the accretion disk has already progressed to an advanced stage during their SSS phase. I argue that also the novae in low-inclination angle systems possess a reformed accretion disk. The viewing angle dependence requires non-symmetrical modeling approaches. Early disk reformation can also explain high-amplitude variations that have frequently been observed during the early SSS phase.

  13. Theoretical considerations for X-ray phase contrast mammography by Thomson source

    Energy Technology Data Exchange (ETDEWEB)

    Cedola, A. [Istituto di Fotonica e Nanotecnologie-Consiglio Nazionale delle Ricerche (IFN-CNR), via Cineto Romano 42, I-00156 Roma (Italy); INFN, Sezione di Roma1, Piazzale Aldo Moro2, 00185 Rome (Italy)], E-mail: cedola@ifn.cnr.it; Bukreeva, I.; Lagomarsino, S. [Istituto di Fotonica e Nanotecnologie-Consiglio Nazionale delle Ricerche (IFN-CNR), via Cineto Romano 42, I-00156 Roma (Italy); INFN, Sezione di Roma1, Piazzale Aldo Moro2, 00185 Rome (Italy); Petrillo, V.; Maroli, C. [Universita di Milano, Physics Department and INFN Sezione di Milano Via Celoria 16, 20133 Milano (Italy)

    2009-09-01

    The advent, in the near future, of compact X-ray sources like Thomson Back-Scattering (TBS) will allow the clinical application of advanced X-ray imaging techniques, such as phase contrast, with higher sensitivity and lower impact in terms of dose delivery. In this work, we theoretically investigated the possibility of using such sources for phase contrast imaging of micro-calcifications included in a breast tissue. In our study we analyzed the phase and amplitude distribution of the TBS source and we showed that this source can be used for phase contrast imaging since the source coherence at the sample position is sufficiently high for achieving good contrast and micrometer spatial resolution. Indeed the spatial coherence of a TBS source is closer to that of a synchrotron radiation source, and much better than that of a laboratory source. Moreover, we showed the advantages of phase imaging with respect to standard absorption imaging, in the specific case of micro-calcifications detection.

  14. ASCA and BeppoSAX observations of the peculiar X-ray source 4U1700+24/HD154791

    CERN Document Server

    Dal Fiume, D; Bartolini, C; Del Sordo, S; Frontera, F; Guarnieri, A; Orlandini, M; Palazzi, E; Parmar, A N; Piccioni, A; Santangelo, A; Segreto, A

    2000-01-01

    The X-ray source 4U1700+24/HD154791 is one of the few galactic sources whosecounterpart is an evolved M star. In X-rays the source shows extreme erraticvariability and a complex and variable spectrum. While this strongly suggestsaccretion onto a compact object, no clear diagnosis of binarity was done up tonow. We report on ASCA and BeppoSAX X-ray broad band observations of thissource and on ground optical observations from the Loiano 1.5 m telescope.

  15. Medical imaging using a laser-wakefield driven x-ray source

    Science.gov (United States)

    Cole, Jason; Wood, Jonathan; Lopes, Nelson; Poder, Kristjan; Kamperidis, Christos; Alatabi, Saleh; Bryant, Jonathan; Kneip, Stefan; Mecseki, Katalin; Norris, Dominic; Teboul, Lydia; Westerburg, Henrik; Abel, Richard; Jin, Andi; Symes, Dan; Mangles, Stuart; Najmudin, Zulfikar

    2016-10-01

    Laser-wakefield accelerators driven by high-intensity laser pulses are a proven centimetre-scale source of GeV electron beams. One of the proposed uses for these accelerators is the driving of compact hard x-ray synchrotron light sources. Such sources have been shown to be bright, have small source size and high photon energy, and are therefore interesting for imaging applications. By doubling the focal length at the Astra-Gemini laser facility of the Rutherford Appleton Laboratory, UK, we have significantly improved the average betatron x-ray flux compared to previous experiments. This fact, coupled to the stability of the radiation source, facilitated the acquisition of full 3D tomograms of hard bone tissue and soft mouse neonates, the latter requiring the recording of over 500 successive radiographs. Such multimodal performance is unprecedented in the betatron field and indicates the usefulness of these sources in clinical imaging applications, scalable to very high photon flux without compromising source size or photon energy.

  16. On the origin of two unidentified radio/X-ray sources discovered with XMM-Newton

    CERN Document Server

    García, Federico; Medina, María C; Romero, Gustavo E

    2015-01-01

    We aim at clarifying the nature of the emission of two spatially related unidentified X-ray sources detected with XMM-Newton telescope at intermediate-low Galactic latitude. Observations reveal a point-like source aligned with elongated diffuse emission. The X-ray spectra are best-fitted by absorbed power laws with photon indices ~1.7 for the point-like and ~2.0 for the extended one. Both sources show nonthermal radio-continuum counterparts that might indicate a physical association. From the available data, we did not detect variability on the point-like source in several timescales. Two possible scenarios are analyzed: first, based on HI line absorption, assuming a Galactic origin, we infer a distance upper bound of 10^32 erg/s and >7.5 x 10^32 erg/s, for the point-like and extended sources, respectively; second, an extra-Galactic nature is discussed, where the point-like source might be the core of a radio galaxy and the extended source its lobe. In this case, we compare derived fluxes, spectral indices, a...

  17. A Simple X-ray Spectrometer and PC-based Data Acquisition System for Newly Developed X-ray Source Based on Laser Compton Scattering

    Institute of Scientific and Technical Information of China (English)

    LUO Wen; XU Wang; PAN Qiang-yan; XU Yi; FAN Gong-tao; FAN Guang-wei; YANG Li-feng; LI Yong-jiang; YAN Zhe; XU Ben-ji

    2009-01-01

    A simple X-ray spectrometer and a PC-Based Data Acquisition System(DAS) have been developed newly in Shanghai Institute of Applied Physics(SINAP),Chinese Academy of Sciences (CAS) for the measurement of the X-ray source generated using laser Compton scattering.The system consists of liquid nitrogen cooled high resolution Si(Li) detector,electronics and a DAQ.The Si(Li) detector was designed and made by Center of Advanced Instruments in SINAP,CAS,it allows us to measure X-rays with the energy up to 60 keV and the energy resolution(FWHM) of 184 eV at 5.9 keV.We measured the system uncertainty was 0.2 eV and time drifting of detector was 0.05% both at 5.9 keV.The DAQ was based on Object-Oriented software LabVIEW 7.1,it has data on-line analysis and original data saved functions.

  18. X-ray Energy Spectra of the Super-soft X-ray Sources CAL87 and RXJ0925.7-4758 Observed with ASCA

    CERN Document Server

    Ebisawa, K; Kotani, T; Asai, K; Dotani, T; Nagase, F; Hartmann, H W; Heise, J; Kahabka, P; Van Teeseling, A

    2000-01-01

    We report observation results of the super-soft X-ray sources (SSS) CAL87 and RXJ0925.7-4758 with the X-ray CCD cameras (Solid-state Imaging Spectrometer; SIS) on-board the ASCA satellite. We have applied theoretical spectral models to CAL87, and constrained the white dwarf mass and intrinsic luminosity as 0.8 - 1.2 M_solar and 4 x 10^{37}- 1.2 x 10^{38} erg s^{-1}, respectively. However, we have found the observed luminosity is an order of magnitude smaller than the theoretical estimate, which indicates the white dwarf is permanently blocked by the accretion disk, and we are observing a scattering emission by a fully ionized accretion disk corona (ADC) whose column density is ~ 1.5 x 10^{23} cm^{-2}. Through simulation, we have shown that the orbital eclipse can be explained by the ADC model, such that a part of the extended X-ray emission from the ADC is blocked by the companion star filling its Roche lobe. We have found that very high surface gravity and temperature, ~ 10^{10} cm s^{-2} and ~ 100 eV respec...

  19. Fast plasma discharge capillary design as a high power throughput soft x-ray emission source.

    Science.gov (United States)

    Wyndham, E S; Favre, M; Valdivia, M P; Valenzuela, J C; Chuaqui, H; Bhuyan, H

    2010-09-01

    We present the experimental details and results from a low energy but high repetition rate compact plasma capillary source for extreme ultraviolet and soft x-ray research and applications. Two lengths of capillary are mounted in two versions of a closely related design. The discharge operates in 1.6 and 3.2 mm inner diameter alumina capillaries of lengths 21 and 36 mm. The use of water both as dielectric and as coolant simplifies the compact low inductance design with nanosecond discharge periods. The stored electrical energy of the discharge is approximately 0.5 J and is provided by directly charging the capacitor plates from an inexpensive insulated-gate bipolar transistor in 1 μs or less. We present characteristic argon spectra from plasma between 30 and 300 Å as well as temporally resolved x-ray energy fluence in discrete bands on axis. The spectra also allow the level of ablated wall material to be gauged and associated with useful capillary lifetime according to the chosen configuration and energy storage. The connection between the electron beams associated with the transient hollow cathode mechanism, soft x-ray output, capillary geometry, and capillary lifetime is reported. The role of these e-beams and the plasma as measured on-axis is discussed. The relation of the electron temperature and the ionization stages observed is discussed in the context of some model results of ionization in a non-Maxwellian plasma.

  20. Beamline and exposure station for deep x-ray lithography at the Advanced Photon Source

    Energy Technology Data Exchange (ETDEWEB)

    Lai, B.; Mancini, D.C.; Yun, W.; Gluskin, E.

    1996-12-31

    APS is a third-generation synchrotron radiation source. With an x-ray energy of 19.5 keV and highly collimated beam (<0.1 mrad), APS is well suited for producing high-aspect-ratio microstructures in thick resist films (> 1 mm) using deep x-ray lithography (DXRL). The 2-BM beamline was constructed and will be used for DXRL at APS. Selection of appropriate x-ray energy range is done through a variable-angle mirror and various filters in the beamline. At the exposure station, the beam size will be 100(H) x 5(V) mm{sup 2}. Uniform exposure will be achieved by a high-speed (100 mm/sec) vertical scanner, which allows precise angular ({approximately}0.1 mrad) and positional (< 1 {mu}m) control of the sample, allowing full use of the highly collimated beam for lateral accuracy and control of sidewall slopes during exposure of thick resists, as well as generation of conicals and other profiles. For 1-mm-thick PMMA, a 100 x 25 mm{sup 2} area can be fully exposed in about 1/2 hr, while even 10-mm-thick PMMA will require only 2-3 hours.

  1. The XMM-LSS catalogue: X-ray sources and associated multiwavelength data. Version II

    CERN Document Server

    Chiappetti, L; Pacaud, F; Pierre, M; Gueguen, A; Paioro, L; Polletta, M; Melnyk, O; Elyiv, A; Surdej, J; Faccioli, L

    2012-01-01

    We present the final release of the multi-wavelength XMM-LSS data set,covering the full survey area of 11.1 square degrees, with X-ray data processed with the latest XMM-LSS pipeline version. The present publication supersedes the Pierre et al.(2007) catalogue pertaining to the initial 5 square degrees. We provide X-ray source lists in the customary energy bands (0.5-2 and 2-10 keV) for a total of 6721 objects in the deep full-exposure catalogue and 5572 in the 10ks-limited one, above a detection likelihood of 15 in at least one band. We also provide a multiwavelength catalogue, cross-correlating our list with IR, NIR, optical and UV catalogues. Customary data products (X-ray FITS images, CFHTLS and SWIRE thumbnail images) are made available together with our interactively queriable database in Milan, while a static snapshot of the catalogues will be supplied to CDS, as soon as final acceptance is completed.

  2. Aerogel Cherenkov detector for characterizing the intense flash x-ray source, Cygnus, spectrum

    Science.gov (United States)

    Kim, Y.; Herrmann, H. W.; McEvoy, A. M.; Young, C. S.; Hamilton, C.; Schwellenbach, D. D.; Malone, R. M.; Kaufman, M. I.; Smith, A. S.

    2016-11-01

    An aerogel Cherenkov detector is proposed to measure the X-ray energy spectrum from the Cygnus—intense flash X-ray source operated at the Nevada National Security Site. An array of aerogels set at a variety of thresholds between 1 and 3 MeV will be adequate to map out the bremsstrahlung X-ray production of the Cygnus, where the maximum energy of the spectrum is normally around 2.5 MeV. In addition to the Cherenkov radiation from aerogels, one possible competing light-production mechanism is optical transition radiation (OTR), which may be significant in aerogels due to the large number of transitions from SiO2 clusters to vacuum voids. To examine whether OTR is a problem, four aerogel samples were tested using a mono-energetic electron beam (varied in the range of 1-3 MeV) at NSTec Los Alamos Operations. It was demonstrated that aerogels can be used as a Cherenkov medium, where the rate of the light production is about two orders magnitude higher when the electron beam energy is above threshold.

  3. Supercritical Accretion Discs in Ultraluminous X-ray Sources and SS 433

    CERN Document Server

    Fabrika, Sergei; Vinokurov, Alexander; Sholukhova, Olga; Shidatsu, Megumi

    2015-01-01

    The black hole mass and accretion rate in Ultraluminous X-ray sources (ULXs) in external galaxies, whose X-ray luminosities exceed those of the brightest black holes in our Galaxy by hundreds and thousands of times$^{1,2}$, is an unsolved problem. Here we report that all ULXs ever spectroscopically observed have about the same optical spectra apparently of WNL type (late nitrogen Wolf-Rayet stars) or LBV (luminous blue variables) in their hot state, which are very scarce stellar objects. We show that the spectra do not originate from WNL/LBV type donors but from very hot winds from the accretion discs with nearly normal hydrogen content, which have similar physical conditions as the stellar winds from these stars. The optical spectra are similar to that of SS 433, the only known supercritical accretor in our Galaxy$^{3}$, although the ULX spectra indicate a higher wind temperature. Our results suggest that ULXs with X-ray luminosities of $\\sim 10^{40}$ erg s$^{-1}$ must constitute a homogeneous class of objec...

  4. The Coherent X-ray Imaging (CXI) Instrument at the Linac Coherent Light Source (LCLS)

    Energy Technology Data Exchange (ETDEWEB)

    Boutet, Sebastien; Williams, Garth J.; /SLAC

    2011-08-16

    The Linac Coherent Light Source (LCLS) has become the first ever operational hard X-ray Free Electron Laser in 2009. It will operate as a user facility capable of delivering unique research opportunities in multiple fields of science. The LCLS and the LCLS Ultrafast Science Instruments (LUSI) construction projects are developing instruments designed to make full use of the capabilities afforded by the LCLS beam. One such instrument is being designed to utilize the LCLS coherent beam to image with high resolution any sub-micron object. This instrument is called the Coherent X-ray Imaging (CXI) instrument. This instrument will provide a flexible optical system capable of tailoring key beam parameters for the users. A suite of shot-to-shot diagnostics will also be provided to characterize the beam on every pulse. The provided instrumentation will include multi-purpose sample environments, sample delivery and a custom detector capable of collecting 2D data at 120 Hz. In this article, the LCLS will be briefly introduced along with the technique of Coherent X-ray Diffractive Imaging (CXDI). A few examples of scientific opportunities using the CXI instrument will be described. Finally, the conceptual layout of the instrument will be presented along with a description of the key requirements for the overall system and specific devices required.

  5. RF deflecting cavity design for Berkeley ultrafast X-ray source

    Science.gov (United States)

    Li, D.; Corlett, J.

    2002-05-01

    Our proposed source for production of ultra-short (less than 100 fs FWHM) x-ray pulses utilizes a scheme for manipulation of the relatively long (2 ps) electron bunch in transverse phase-space, followed by compression of the emitted x-ray pulse in crystal optics. In order to compress the x-ray pulses, RF cavities operating in a dipole mode (TM110-like) are required to deflect the head and tail of a 2.5 GeV bunch in opposite directions. For a 2 ps duration electron bunch, an 8.5 MV deflecting voltage is required at a RF frequency of 3.9 GHz. In this paper, we will present a preliminary cavity design based on numerical simulations performed by MAFIA and URMEL codes. Seven-cell superconducting p mode dipole RF cavities are proposed to provide the necessary deflecting voltage. Due to the presence of beam iris, the mavities operate in a hybrid mode where TM and TE like modes co-exist. Even on mhe beam axis, both magnetic and electric fields contribute to the transverse mick. Lower order monopole modes (LOMs) in the cavities may cause energy spread of the electron beam and need to be damped. The effects of the LOMs on beam dynamics are estimated. Possible damping schemes will be discussed.

  6. RF deflecting cavity design for Berkeley ultrafast X-ray source

    Energy Technology Data Exchange (ETDEWEB)

    Li, Derun; Corlett, J.

    2002-05-30

    Our proposed source for production of ultra-short (less than 100 fs FWHM) x-ray pulses utilizes a scheme for manipulation of the relatively long ({approx}2 ps) electron bunch in transverse phase-space, followed by compression of the emitted x-ray pulse in crystal optics [1]. In order to compress the x-ray pulses, RF cavities operating in a dipole mode (TM{sub 110}-like) are required to deflect the head and tail of a 2.5 GeV bunch in opposite directions. For a 2 ps duration electron bunch, an 8.5 MV deflecting voltage is required at a RF frequency of 3.9 GHz. In this paper, we will present a preliminary cavity design based on numerical simulations performed by MAFIA and URMEL codes. Seven-cell superconducting {pi} mode dipole RF cavities are proposed to provide the necessary deflecting voltage. Due to the presence of beam iris, the cavities operate in a hybrid mode where TM and TE like modes co-exist. Even on the beam axis, both magnetic and electric fields contribute to the transverse kick. Lower order monopole modes (LOMs) in the cavities may cause energy spread of the electron beam and need to be damped. The effects of the LOMs on beam dynamics are estimated. Possible damping schemes will be discussed.

  7. Asymmetric Dual Axis Energy Recovery Linac for Ultra-High Flux sources of coherent X-ray/THz radiation: Investigations Towards its Ultimate Performance

    CERN Document Server

    Ainsworth, R; Konoplev, I V; Seryi, A

    2015-01-01

    Truly compact and high current, efficient particle accelerators are required for sources of coherent high brightness and intensity THz and X-Ray radiation to be accepted by university or industrial R&D laboratories. The demand for compactness and efficiency can be satisfied by superconducting RF energy recovery linear accelerators (SRF ERL) allowing effectively minimising the footprint and maximising the efficiency of the system. However such set-ups are affected by regenerative beam-break up (BBU) instabilities which limit the beam current and may terminate the beam transport as well as energy recuperation. In this paper we suggest and discuss a SRF ERL with asymmetric configuration of accelerating and decelerating cavities resonantly coupled. In this model of SRF ERL we propose an electron bunch passing through accelerating and decelerating cavities each once and we show that in this case the regenerative BBU instability can be minimised allowing high currents to be achieved. We study the BBU start curr...

  8. Table-top laser-driven ultrashort electron and X-ray source: the CIBER-X source project

    Science.gov (United States)

    Girardeau-Montaut, Jean-Pierre; Kiraly, Bélà; Girardeau-Montaut, Claire; Leboutet, Hubert

    2000-09-01

    We report on the development of a new laser-driven table-top ultrashort electron and X-ray source, also called the CIBER-X source . X-ray pulses are produced by a three-step process which consists of the photoelectron emission from a thin metallic photocathode illuminated by 16 ps duration laser pulses at 213 nm. The e-gun is a standard Pierce diode electrode type, in which electrons are accelerated by a cw electric field of ˜11 MV/m up to a hole made in the anode. The photoinjector produces a train of 70-80 keV electron pulses of ˜0.5 nC and 20 A peak current at a repetition rate of 10 Hz. The electrons are then transported outside the diode along a path of 20 cm length, and are focused onto a target of thullium by magnetic fields produced by two electromagnetic coils. X-rays are then produced by the impact of electrons on the target. Simulations of geometrical, electromagnetic fields and energetic characteristics of the complete source were performed previously with the assistance of the code PIXEL1 also developed at the laboratory. Finally, experimental electron and X-ray performances of the CIBER-X source as well as its application to very low dose imagery are presented and discussed. source Compacte d' Impulsions Brèves d' Electrons et de Rayons X

  9. Highly charged ion X-rays from Electron-Cyclotron Resonance Ion Sources

    OpenAIRE

    Indelicato, Paul; Boucard, S.; Covita, D. S.; Gotta, D.; Gruber, A; Hirtl, A.; Fuhrmann, H.; Le Bigot, E.-O.; Schlesser, S.; dos Santos, J. M. F.; Simons, L.M.; Stingelin, L.; Trassinelli, Martino; Veloso, J.; Wasser, A.

    2006-01-01

    Radiation from the highly-charged ions contained in the plasma of Electron-Cyclotron Resonance Ion Sources constitutes a very bright source of X-rays. Because the ions have a relatively low kinetic energy ($\\approx 1$~eV) transitions can be very narrow, containing only small Doppler broadening. We describe preliminary accurate measurements of two and three-electron ions with $Z=16$--18. We show how these measurement can test sensitively many-body relativistic calculations or can be used as X-...

  10. Polycapillary X-ray lens for the secondary focusing Beijing synchrotron radiation source

    Institute of Scientific and Technical Information of China (English)

    Li Yu-De; Lin Xiao-Yan; Liu Shi-Gang; He Jin-Long; Guo Fei; Sun Tian-Xi; Liu Peng

    2013-01-01

    According to intensity distribution of the synchrotron radiation source focused by a toroidal mirror at the Beijing synchrotron radiation biological macromolecule station,theoretical modeling of the Beijing synchrotron radiation source is developed for capillary optics.Using this theoretical modeling,the influences of the configuration curve of the polycapillary X-ray lens on transmission efficiency and working distance are analyzed.The experimental results of the transmission efficiency and working distance at the biological macromolecule station are in good agreement with the theoretical results.

  11. Spectral Classification of Optical Counterparts to ROSAT All-Sky Survey X-ray Sources

    CERN Document Server

    Dragomir, D; Rutledge, R E; Dragomir, Diana; Roy, Philippe; Rutledge, Robert E.

    2007-01-01

    Previous work statistically identified 5492 optical counterparts, with approximately 90% confidence, from among the approximately 18,000 X-ray sources appearing in the ROSAT All-Sky Survey Bright Source Catalog (RASS/BSC). Using low resolution spectra in the wavelength range 3700-7900 angstroms, we present spectroscopic classifications for 195 of these counterparts which have not previously been classified. Of these 195, we find 168 individual stars of F, G, K or M type, 6 individual stars of unknown type, 6 double stars, 6 AGN or galaxies and 7 unclassifiable objects; the spectra of the 2 remaining objects were saturated.

  12. Research and Development for X-Ray Optics and Diagnostics on the Linac Coherent Source (LCLS)

    Energy Technology Data Exchange (ETDEWEB)

    Bionta, R M; Arthur, J; Chapman, H; Craig, B; Klingmann, J; Kuba, J; London, R A; Ott, L; Ryutov, D; Shepherd, R; Shlyaptsev, V; Wootton, A

    2002-09-24

    The Linac Coherent Light Source (LCLS) is a 1.5 to 15 {angstrom} wavelength Free-Electron Laser (PEL), under development at the Stanford Linear Accelerator Center (SLAC). The photon output consists of high brightness, transversely coherent pulses with duration < 300 fs, together with a broad spontaneous spectrum. The output energy density per unit area, pulse duration, repetition rate, and small FEL spot size pose special challenges for optical components and diagnostics downstream of the undulator. Planning for the photon beam transport, manipulation and diagnostics downstream of the undulator has begun.

  13. The Chandra Galactic Bulge Survey: optical catalogue and point-source counterparts to X-ray sources

    Science.gov (United States)

    Wevers, T.; Hodgkin, S. T.; Jonker, P. G.; Bassa, C.; Nelemans, G.; van Grunsven, T.; Gonzalez-Solares, E. A.; Torres, M. A. P.; Heinke, C.; Steeghs, D.; Maccarone, T. J.; Britt, C.; Hynes, R. I.; Johnson, C.; Wu, Jianfeng

    2016-06-01

    As part of the Chandra Galactic Bulge Survey (GBS), we present a catalogue of optical sources in the GBS footprint. This consists of two regions centred at Galactic latitude b = 1.5° above and below the Galactic Centre, spanning (l × b) = (6° × 1°). The catalogue consists of two or more epochs of observations for each line of sight in r', i' and H α filters. The catalogue is complete down to r' = 20.2 and i' = 19.2 mag; the mean 5σ depth is r' = 22.5 and i' = 21.1 mag. The mean root-mean-square residuals of the astrometric solutions is 0.04 arcsec. We cross-correlate this optical catalogue with the 1640 unique X-ray sources detected in Chandra observations of the GBS area, and find candidate optical counterparts to 1480 X-ray sources. We use a false alarm probability analysis to estimate the contamination by interlopers, and expect ˜10 per cent of optical counterparts to be chance alignments. To determine the most likely counterpart for each X-ray source, we compute the likelihood ratio for all optical sources within the 4σ X-ray error circle. This analysis yields 1480 potential counterparts (˜90 per cent of the sample). 584 counterparts have saturated photometry (r' ≤ 17, i' ≤ 16), indicating these objects are likely foreground sources and the real counterparts. 171 candidate counterparts are detected only in the i' band. These sources are good qLMXB and CV candidates as they are X-ray bright and likely located in the Bulge.

  14. X-ray Sources by Energy Recovered Linacs and Their Needed R&D

    Energy Technology Data Exchange (ETDEWEB)

    Geoffrey Krafft, Stephen Benson, Michael Borland, David Douglas, David Dowell, Carlos Hernandez-Garcia, Dmitry Kayran, Robert Legg, Elizabeth Moog, Takashi Obina, Robert Rimmer, Vitaly Yakimenko

    2011-05-01

    In this paper we review the current state of research on energy recovered linacs as drivers for future X-ray sources. For many types of user experiments, such sources may have substantial advantages compared to the workhorse sources of the present: high energy storage rings. Energy recovered linacs need to be improved beyond present experience in both energy and average current to support this application. To build an energy recovered linac based X-ray user facility presents many interesting challenges. We present summaries on the Research and Development (R&D) topics needed for full development of such a source, including the discussion at the Future Light Sources Workshop held in Gaithersberg, Maryland on September 15-17, 2009. A first iteration of an R&D plan is presented that is founded on the notion of building a set of succeedingly larger test accelerators exploring cathode physics, high average current injector physics, and beam recirculation and beam energy recovery at high average current. Our basic conclusion is that a reviewable design of such a source can be developed after an R&D period of reasonably short duration.

  15. The BMW (Brera-Multiscale-Wavelet) Catalogue of Serendipitous X-ray Sources

    CERN Document Server

    Lazzati, D; Covino, S; Israel, G L; Guzzo, L; Mignani, R P; Moretti, A; Panzera, M R; Tagliaferri, G

    2000-01-01

    In collaboration with the Observatories of Palermo and Rome and the SAX-SDC we are constructing a multi-site interactive archive system featuring specific analysis tools. In this context we developed a detection algorithm based on the Wavelet Transform (WT) and performed a systematic analysis of all ROSAT-HRI public data (~3100 observations +1000 to come). The WT is specifically suitable to detect and characterize extended sources while properly detecting point sources in very crowded fields. Moreover, the good angular resolution of HRI images allows the source extension and position to be accurately determined. This effort has produced the BMW (Brera Multiscale Wavelet) catalogue, with more than 19,000 sources detected at the 4.2 sigma level. For each source detection we have information on the X-ray flux and extension, allowing for instance to select complete samples of extended X-ray sources such as candidate clusters of galaxies or SNR's. Here we present an overview of first results from several undergoin...

  16. The BMW (Brera-Multiscale-Wavelet) Catalogue of Serendipitous X-Ray Sources

    Science.gov (United States)

    Lazzati, Davide; Campana, Sergio; Covino, Stefano; Israel, Gian L.; Guzzo, Luigi; Mignani, Roberto; Moretti, Alberto; Panzera, Maria R.; Tagliaferri, Gianpiero

    In collaboration with the Observatories of Palermo and Rome and the SAX-SDC we are constructing a multi-site interactive archive system featuring specific analysis tools. In this context we developed a detection algorithm based on the Wavelet Transform (WT) and performed a systematic analysis of all ROSATHRI public data (˜3100 observations +1000 to come). The WT is specifically suitable to detect and characterize extended sources while properly detecting point sources in very crowded fields. Moreover, the good angular resolution of HRI images allows the source extension and position to be accurately determined. This effort has produced the BMW (Brera Multiscale Wavelet) catalogue, with more than 19,000 sources detected at the ˜4.2σ level. For each source detection we have information on the X-ray flux and extension, allowing for instance to select complete samples of extended X-ray sources such as candidate clusters of galaxies or SNR's. Details about the detection algorithm and the catalogue can be found in Lazzati et al. 1999 and Campana et al. 1999. Here we shall present an overview of first results from several undergoing projects which make use of the BMW catalogue.

  17. A high-brightness source of polarization-entangled photons optimized for applications in free space

    CERN Document Server

    Steinlechner, Fabian; Jofre, Marc; Weier, Henning; Perez, Daniel; Jennewein, Thomas; Ursin, Rupert; Rarity, John; Mitchell, Morgan W; Torres, Juan P; Weinfurter, Harald; Pruneri, Valerio; 10.1364/OE.20.009640

    2012-01-01

    We present a simple but highly efficient source of polarization-entangled photons based on spontaneous parametric down-conversion (SPDC) in bulk periodically poled potassium titanyl phosphate crystals (PPKTP) pumped by a 405 nm laser diode. Utilizing one of the highest available nonlinear coefficients in a non-degenerate, collinear type-0 phase-matching configuration, we generate polarization entanglement via the crossed-crystal scheme and detect 0.64 million photon pair events/s/mW, while maintaining an overlap fidelity with the ideal Bell state of 0.98 at a pump power of 0.025 mW.

  18. Time-resolved and in-situ X-ray scattering methods beyond photoactivation: Utilizing high-flux X-ray sources for the study of ubiquitous non-photoactive proteins.

    Science.gov (United States)

    Jain, Rohit; Techert, Simone

    2016-01-01

    X-ray scattering technique, comprising of small-angle/wide-angle X-ray scattering (SAXS/WAXS) techniques is increasingly used to characterize the structure and interactions of biological macromolecules and their complexes in solution. It is a method of choice to characterize the flexible, partially folded and unfolded protein systems. X-ray scattering is the last resort for proteins that cannot be investigated by crystallography or NMR and acts as a complementary technique with different biophysical techniques to answer challenging scientific questions. The marriage of the X-ray scattering technique with the fourth dimension "time" yields structural dynamics and kinetics information for protein motions in hierarchical timescales from picoseconds to days. The arrival of the high-flux X-ray beam at third generation synchrotron sources, exceptional X-ray optics, state-of-the-art detectors, upgradation of X-ray scattering beamlines with microfluidics devices and advanced X-ray scattering data analysis procedures are the important reasons behind the shining years of X-ray scattering technique. The best days of the X-ray scattering technique are on the horizon with the advent of the nanofocus X-ray scattering beamlines and fourth generation X-ray lightsources, i.e., free electron lasers (XFELs). Complementary to the photon-triggered time-resolved X-ray scattering techniques, we will present an overview of the time-resolved and in-situ X-ray scattering techniques for structural dynamics of ubiquitous non-photoactive proteins.

  19. The XXL Survey. VI. The 1000 brightest X-ray point sources

    Science.gov (United States)

    Fotopoulou, S.; Pacaud, F.; Paltani, S.; Ranalli, P.; Ramos-Ceja, M. E.; Faccioli, L.; Plionis, M.; Adami, C.; Bongiorno, A.; Brusa, M.; Chiappetti, L.; Desai, S.; Elyiv, A.; Lidman, C.; Melnyk, O.; Pierre, M.; Piconcelli, E.; Vignali, C.; Alis, S.; Ardila, F.; Arnouts, S.; Baldry, I.; Bremer, M.; Eckert, D.; Guennou, L.; Horellou, C.; Iovino, A.; Koulouridis, E.; Liske, J.; Maurogordato, S.; Menanteau, F.; Mohr, J. J.; Owers, M.; Poggianti, B.; Pompei, E.; Sadibekova, T.; Stanford, A.; Tuffs, R.; Willis, J.

    2016-06-01

    Context. X-ray extragalactic surveys are ideal laboratories for the study of the evolution and clustering of active galactic nuclei (AGN). Usually, a combination of deep and wide surveys is necessary to create a complete picture of the population. Deep X-ray surveys provide the faint population at high redshift, while wide surveys provide the rare bright sources. Nevertheless, very wide area surveys often lack the ancillary information available for modern deep surveys. The XXL survey spans two fields of a combined 50 deg2 observed for more than 6Ms with XMM-Newton, occupying the parameter space that lies between deep surveys and very wide area surveys; at the same time it benefits from a wealth of ancillary data. Aims: This paper marks the first release of the XXL point source catalogue including four optical photometry bands and redshift estimates. Our sample is selected in the 2 - 10 keV energy band with the goal of providing a sizable sample useful for AGN studies. The limiting flux is F2 - 10 keV = 4.8 × 10-14 erg s-1 cm-2. Methods: We use both public and proprietary data sets to identify the counterparts of the X-ray point-like sources by means of a likelihood ratio test. We improve upon the photometric redshift determination for AGN by applying a Random Forest classification trained to identify for each object the optimal photometric redshift category (passive, star forming, starburst, AGN, quasi-stellar objects (QSO)). Additionally, we assign a probability to each source that indicates whether it might be a star or an outlier. We apply Bayesian analysis to model the X-ray spectra assuming a power-law model with the presence of an absorbing medium. Results: We find that the average unabsorbed photon index is ⟨Γ⟩ = 1.85 ± 0.40 while the average hydrogen column density is log ⟨NH⟩ = 21.07 ± 1.2 cm-2. We find no trend of Γ or NH with redshift and a fraction of 26% absorbed sources (log NH> 22) consistent with the literature on bright sources (log

  20. High brightness laser source based on polarization coupling of two diode lasers with asymmetric feedback

    DEFF Research Database (Denmark)

    Thestrup, B.; Chi, M.; Sass, B.

    2003-01-01

    In this letter, we show that polarization coupling and asymmetric diode-laser feedback can be used to combine two diode-laser beams with low spatial coherence into a single beam with high spatial coherence. The coupled laser source is based on two similar laser systems each consisting of a 1 mumx......200 mum broad area laser diode applied with a specially designed feedback circuit. When operating at two times threshold, 50% of the freely running system output power is obtained in a single beam with an M-2 beam quality factor of 1.6+/-0.1, whereas the M-2 values of the two freely running diode...... lasers are 29+/-1 and 34+/-1, respectively. (C) 2003 American Institute of Physics....

  1. Prospective gated chest tomosynthesis using CNT X-ray source array

    Science.gov (United States)

    Shan, Jing; Burk, Laurel; Wu, Gongting; Lee, Yueh Z.; Heath, Michael D.; Wang, Xiaohui; Foos, David; Lu, Jianping; Zhou, Otto

    2015-03-01

    Chest tomosynthesis is a low-dose 3-D imaging modality that has been shown to have comparable sensitivity as CT in detecting lung nodules and other lung pathologies. We have recently demonstrated the feasibility of stationary chest tomosynthesis (s-DCT) using a distributed CNT X-ray source array. The technology allows acquisition of tomographic projections without moving the X-ray source. The electronically controlled CNT x-ray source also enables physiologically gated imaging, which will minimize image blur due to the patient's respiration motion. In this paper, we investigate the feasibility of prospective gated chest tomosynthesis using a bench-top s-DCT system with a CNT source array, a high- speed at panel detector and realistic patient respiratory signals captured using a pressure sensor. Tomosynthesis images of inflated pig lungs placed inside an anthropomorphic chest phantom were acquired at different respiration rate, with and without gating for image quality comparison. Metal beads of 2 mm diameter were placed on the pig lung for quantitative measure of the image quality. Without gating, the beads were blurred to 3:75 mm during a 3 s tomosynthesis acquisition. When gated to the end of the inhalation and exhalation phase the detected bead size reduced to 2:25 mm, much closer to the actual bead size. With gating the observed airway edges are sharper and there are more visible structural details in the lung. Our results demonstrated the feasibility of prospective gating in the s-DCT, which substantially reduces image blur associated with lung motion.

  2. 3D polymer gel dosimetry and Geant4 Monte Carlo characterization of novel needle based X-ray source

    Science.gov (United States)

    Liu, Y.; Sozontov, E.; Safronov, V.; Gutman, G.; Strumban, E.; Jiang, Q.; Li, S.

    2010-11-01

    In the recent years, there have been a few attempts to develop a low energy x-ray radiation sources alternative to conventional radioisotopes used in brachytherapy. So far, all efforts have been centered around the intent to design an interstitial miniaturized x-ray tube. Though direct irradiation of tumors looks very promising, the known insertable miniature x-ray tubes have many limitations: (a) difficulties with focusing and steering the electron beam to the target; (b)necessity to cool the target to increase x-ray production efficiency; (c)impracticability to reduce the diameter of the miniaturized x-ray tube below 4mm (the requirement to decrease the diameter of the x-ray tube and the need to have a cooling system for the target have are mutually exclusive); (c) significant limitations in changing shape and energy of the emitted radiation. The specific aim of this study is to demonstrate the feasibility of a new concept for an insertable low-energy needle x-ray device based on simulation with Geant4 Monte Carlo code and to measure the dose rate distribution for low energy (17.5 keV) x-ray radiation with the 3D polymer gel dosimetry.

  3. A Chandra Archival Survey of the X-ray Source Populations of Nearby Galaxies

    Science.gov (United States)

    Kilgard, Roy E.; Wright, Simon; Fonseca, Gloria; Santini, Anthony; Fritze, Hannah

    2017-08-01

    We present results of a volume-limited Chandra archival survey of the X-ray point sources populations of nearby galaxies. We define our sample to include all observations of at least 5 ks of any galaxy within 15 Mpc. The complete sample is in excess of 15000 individual point sources, approximately half of which are contained with the D25 ellipses of galaxies. We present spectral and temporal analyses of this sample, from which we can cleanly define the parameter spaces in color, variability, and luminosity occupied by different classes of sources (e.g., LMXBs vs. HMXBs). For all sources, we perform detailed spatial modeling, spectral fitting, multiband X-ray photometry, and multimodal timing analyses. We further discuss source classes as a function of host galaxy morphology, star formation rate, stellar mass distribution, optical extent, interaction history, and metallicity. Finally, we discuss incompleteness in the sample, and what observations can be conducted in the following years to fill the gap.

  4. X-ray Sources with Periodic Variability in a Deep Chandra Image of the Galactic Center

    CERN Document Server

    Muno, M P; Bautz, M W; Brandt, W N; Garmire, G P; Ricker, G R

    2003-01-01

    We report the discovery of eight X-ray sources with periodic variability in 487 ks of observations of the Galactic center with Chandra. The sources are identified from a sample of 285 objects detected with 100-4200 net counts. Their periods range from 300 s to 4.5 h with amplitudes between 40% and 70% rms. They have luminosities of (1 - 5) \\times 10^{32} erg/sec (2--8 keV at 8 kpc). The spectra of seven of the eight sources are consistent with Gamma = 0 power laws absorbed by gas and dust with a column density equal to or higher than that toward the Galactic Center (6 times 10^{22} cm^{-2}). Four of these sources also exhibit emission lines near 6.7 keV from He-like Fe, with equivalent widths of 600-1000 eV. These properties are consistent with both magnetically accreting cataclysmic variables and wind-accreting neutron stars in high-mass X-ray binaries. The eighth source has an absorbing column of 5 \\times 10^{21} cm^{-2} that places it in the foreground. Its spectrum is consistent with either a Gamma = 1.4 ...

  5. X-ray time variability across the atoll source states of 4U 1636--53

    CERN Document Server

    Altamirano, D; Méndez, M; Jonker, P G; Klein-Wolt, M; Lewin, W H G

    2008-01-01

    We have studied the rapid X-ray time variability in 149 pointed observations with the \\textit{Rossi X-ray Timing Explorer} (RXTE)'s Proportional Counter Array of the atoll source 4U~1636--53 in the banana state and, for the first time with RXTE, in the island state. We compare the frequencies of the variability components of 4U~1636--53 with those in other atoll and Z-sources and find that 4U~1636--53 follows the universal scheme of correlations previously found for other atoll sources at (sometimes much) lower luminosities. Our results on the hectohertz QPO suggest that the mechanism that sets its frequency differs from that for the other components, while the amplitude setting mechanism is common. A previously proposed interpretation of the narrow low-frequency QPO frequencies in different sources in terms of harmonic mode switching is not supported by our data, nor by some previous data on other sources and the frequency range that this QPO covers is found not to be related to spin, angular momentum or lum...

  6. A variable ultra-luminous X-ray source in the colliding galaxy NGC 7714

    CERN Document Server

    Soria, R; Soria, Roberto; Motch, Christian

    2004-01-01

    We studied the colliding galaxy NGC 7714 with two XMM-Newton observations, six months apart. The galaxy contains two bright X-ray sources: we show that they have different physical nature. The off-nuclear source is an accreting compact object, one of the brightest ultraluminous X-ray sources (ULXs) found to date. It showed spectral and luminosity changes between the two observations, from a low/soft to a high/hard state; in the high state, it reached L_x ~ 6 x 10^{40} erg/s. Its lightcurve in the high state suggests variability on a ~ 2-hr timescale. Its peculiar location, where the tidal bridge between NGC 7714 and NGC 7715 joins the outer stellar ring of NGC 7714, makes it an interesting example of the connection between gas flows in colliding galaxies and ULX formation. The nuclear source (L_x ~ 10^{41} erg/s) coincides with a starburst region, and is the combination of thin thermal plasma emission and a point-source contribution (with a power-law spectrum). Variability in the power-law component between t...

  7. PULSED CAPILLARY DISCHARGE CHARACTERIZATION FOR SOFT X-RAY MICROSCOPY APPLICATIONS

    OpenAIRE

    VALDIVIA LEIVA; MARIA PIA

    2011-01-01

    The hollow cathode capillary discharge is of great interest as a high brightness, short pulse soft x-ray source. This thesis presents work done in the development, modifications, and subsequent characterization of a compact plasma source comprised of a pulsed capillary discharge exploiting hollow cathode dynamics. The low inductance, low stored energy, source is optimized using optical, electrical, x-ray, and e-beam diagnostics. The effect of parameters on the capillary phys...

  8. Development of high-brightness high-power fiber laser pump sources

    Science.gov (United States)

    Priest, J. A.; Faircloth, Brian O.; Swint, Reuel B.; Coleman, James J.; Forbes, David V.; Zediker, Mark S.

    2004-06-01

    High power fiber lasers have strong potential for use in both commercial and military applications. Improved wall plug efficiency over Nd:YAG and CO2 lasers combined with up to a 10-fold improvement in beam quality, make fiber lasers extremely attractive for industrial applications such as welding and cutting. In military applications, fiber lasers offer a simplified logistic train, a deep magazine limited only by electric power, and a compact footprint, allowing theater defense and self-protection of combat platforms with speed of light engagement and flexible response. Commercial viability of these systems, however, is limited by the availability of compact, cost effective, and reliable diode laser pump sources in the multi-kilowatt regime. The relatively low brightness of diode laser sources has complicated the task of building high power pumps at a reasonable cost. In response to this need, Nuvonyx, Inc. in conjunction with the University of Illinois at Urbana-Champaign, has been developing a new technology for producing high power, single lateral mode devices which do not suffer form the instabilities mentioned above. The waveguide consists of a narrow section, approximately 2 μm wide, which flares to approximately 12 μm wide at the output facet. The flaring of the waveguide increases the gain volume and reduces the optical power density at the facet allowing for higher output power capability. The index guide is defined using an epitaxial process which allows the confinement of the mode to be reduced as the width of the guide expands. Thus, the mode is confined in a single mode waveguide throughout the cavity maintaining stability of the mode to the emitting facet. In November 2002, Nuvonyx, Inc. was awarded a contract with the Air Force Research Lab, Kirtland AFB, Albuquerque, NM, to transition these devices to production quality for use in high-power fiber laser pumps. Partnered with Alfalight, Inc. and the University of Illinois, we have begun initial

  9. 2XMM ultraluminous X-ray source candidates in nearby galaxies

    Science.gov (United States)

    Walton, D. J.; Roberts, T. P.; Mateos, S.; Heard, V.

    2011-09-01

    Ultraluminous X-ray sources (ULXs) are some of the most enigmatic X-ray bright sources known to date. It is generally accepted that they cannot host black holes as large as those associated with active galaxies, but they appear to be significantly more luminous than their better understood Galactic X-ray binary (XRB) cousins, while displaying an intriguing combination of differences and similarities with them. Through studying large, representative samples of these sources we may hope to enhance our understanding of them. To this end, we derive a large catalogue of 650 X-ray detections of 470 ULX candidates, located in 238 nearby galaxies, by cross-correlating the 2XMM Serendipitous Survey with the Third Reference Catalogue of Bright Galaxies. The presented dedicated catalogue offers a significant improvement over those previously published in terms of both the number and the contribution of background contaminants, e.g. distant quasars, which we estimate to be at most 24 per cent, but more likely ˜17 per cent. To undertake population studies, we define a 'complete' sub-sample of sources compiled from observations of galaxies with sensitivity limits below 1039 erg s-1. The luminosity function of this sample is consistent with a simple power law of form N(>LX) ∝ L-0.96 ± 0.11X. Although we do not find any statistical requirement for a cut-off luminosity of Lc˜ 1040 erg s-1, as has been reported previously, we are not able to rule out its presence. Also, we find that the number of ULXs per unit galaxy mass, Su, decreases with increasing galaxy mass for ULXs associated with spiral galaxies, and is well modelled with a power law of form Su ∝ M-0.64 ± 0.07. This is in broad agreement with previous results, and is likely to be a consequence of the decrease in specific star formation and increase in metallicity with increasing spiral galaxy mass. Su is consistent with being constant with galaxy mass for sources associated with elliptical galaxies, implying this

  10. X-ray dose reduction by adaptive source equalization and electronic region-of-interest control

    Science.gov (United States)

    Burion, Steve; Sandman, Anne; Bechtel, Kate; Solomon, Edward; Funk, Tobias

    2011-03-01

    Radiation dose is particularly a concern in pediatric cardiac fluoroscopy procedures, which account for 7% of all cardiac procedures performed. The Scanning-Beam Digital X-ray (SBDX) fluoroscopy system has already demonstrated reduced dose in adult patients owing to its high-DQE photon-counting detector, reduced detected scatter, and the elimination of the anti-scatter grid. Here we show that the unique flexible illumination platform of the SBDX system will enable further dose area product reduction, which we are currently developing for pediatric patients, but which will ultimately benefit all patients. The SBDX system has a small-area detector array and a large-area X-ray source with up to 9,000 individually-controlled X-ray focal spots. Each focal spot illuminates a small fraction of the full field of view. To acquire a frame, each focal spot is activated for a fixed number of 1-microsecond periods. Dose reduction is made possible by reducing the number of activations of some of the X-ray focal spots during each frame time. This can be done dynamically to reduce the exposure in areas of low patient attenuation, such as the lung field. This spatially-adaptive illumination also reduces the dynamic range in the full image, which is visually pleasing. Dose can also be reduced by the user selecting a region of interest (ROI) where full image quality is to be maintained. Outside the ROI, the number of activations of each X-ray focal spot is reduced and the image gain is correspondingly increased to maintain consistent image brightness. Dose reduction is dependent on the size of the ROI and the desired image quality outside the ROI. We have developed simulation software that is based on real data and can simulate the performance of the equalization and ROI filtration. This software represents a first step toward real-time implementation of these dose-reduction methods. Our simulations have shown that dose area product reductions of 40% are possible using equalization

  11. K-edge digital subtraction imaging with dichromatic x-ray sources: SNR and dose studies

    Science.gov (United States)

    Sarnelli, A.; Elleaume, H.; Taibi, A.; Gambaccini, M.; Bravin, A.

    2006-09-01

    The aim of the present work is to analytically evaluate the signal to noise ratio (SNR) and the delivered dose in K-edge digital subtraction imaging (KES) using two types of x-ray sources: a monochromatic x-ray source (available at synchrotron radiation facilities and considered as gold standard) and a quasi-monochromatic compact source. The energy separation ΔE between the two monochromatic beams is 1 keV and 4 keV for the two sources, respectively. The evaluation has been performed for both radiography and computed tomography. Different geometries have been studied to mimic clinical situations. In mammography, a pathology perfused by a contrast agent has been modelled; in angiography, a vessel superimposed to a ventricle or a stand-alone artery stenosis has been studied. The SNR and the skin dose have been calculated as a function of the detail diameter, the contrast agent (iodine and gadolinium), and its concentration in the tissues. Results show that for ΔE = 4 keV a slightly higher delivered dose is required to obtain the same SNR with respect to ΔE < 1 keV. A similar study has been performed for KES-CT. Computer simulations of CT images performed with Snark software are shown to validate the analytical calculations.

  12. Solar Flare X-ray Source Motion as a Response to Electron Spectral Hardening

    CERN Document Server

    O'Flannagain, A; Brown, J; Milligan, R; Holman, G

    2013-01-01

    Context: Solar flare hard X-rays (HXRs) are thought to be produced by nonthermal coronal electrons stopping in the chromosphere, or remaining trapped in the corona. The collisional thick target model (CTTM) predicts that sources produced by harder power-law injection spectra should appear further down the legs or footpoints of a flare loop. Therefore, hardening of the injected power-law electron spectrum during flare onset should be concurrent with a descending hard X-ray source. Aims: To test this implication of the CTTM by comparing its predicted HXR source locations with those derived from observations of a solar flare which exhibits a nonthermally-dominated spectrum before the peak in HXRs, known as an early impulsive event. Methods: HXR images and spectra of an early impulsive C-class flare were obtained using the Ramaty High-Energy Solar Spectroscopic Imager (RHESSI). Images were reconstructed to produce HXR source height evolutions for three energy bands. Spatially-integrated spectral analysis was perf...

  13. Deep hard X-ray source counts from a fluctuation analysis of ASCA SIS images

    CERN Document Server

    Gendreau, K C; Fabian, A C

    1997-01-01

    An analysis of the spatial fluctuations in 15 deep ASCA SIS0 images has been conducted in order to probe the 2-10 keV X-ray source counts down to a flux limit 2E-14 erg/cm2/s. Special care has been taken in modelling the fluctuations in terms of the sensitivity maps of every one of the 16 regions (5.6 x 5.6 arcmin2 each) in which the SIS0 has been divided, by means of raytracing simulations with improved optical constants in the X-ray telescope. The very extended `side lobes' (extending up to a couple of degrees) exhibited by these sensitivity maps make our analysis sensitive to both faint on-axis sources and brighter off-axis ones, the former being dominant. The source counts in the range (2-12)E-14 erg/cm2/s are found to be close to a euclidean form which extrapolates well to previous results from higher fluxes and in reasonable agreement with some recent ASCA surveys. However, our results disagree with the deep survey counts by Georgantopoulos et al. (1997). The possibility that the source counts flatten t...

  14. THE BROADBAND XMM-NEWTON AND NuSTAR X-RAY SPECTRA OF TWO ULTRALUMINOUS X-RAY SOURCES IN THE GALAXY IC 342

    Energy Technology Data Exchange (ETDEWEB)

    Rana, Vikram; Harrison, Fiona A.; Walton, Dominic J.; Furst, Felix; Grefenstette, Brian W.; Madsen, Kristin K. [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Bachetti, Matteo; Barret, Didier; Webb, Natalie A. [Université de Toulouse, UPS-OMP, IRAP, Toulouse (France); Miller, Jon M. [Department of Astronomy, University of Michigan, 500 Church Street, Ann Arbor, MI 48109-1042 (United States); Fabian, Andrew C. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom); Boggs, Steven E.; Craig, William W. [Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States); Christensen, Finn C. [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); Ptak, Andrew F.; Zhang, William W. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Stern, Daniel [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States)

    2015-02-01

    We present results for two ultraluminous X-ray sources (ULXs), IC 342 X-1 and IC 342 X-2, using two epochs of XMM-Newton and NuSTAR observations separated by ∼7 days. We observe little spectral or flux variability above 1 keV between epochs, with unabsorbed 0.3-30 keV luminosities being 1.04{sub −0.06}{sup +0.08}×10{sup 40} erg s{sup –1} for IC 342 X-1 and 7.40 ± 0.20 × 10{sup 39} erg s{sup –1} for IC 342 X-2, so that both were observed in a similar, luminous state. Both sources have a high absorbing column in excess of the Galactic value. Neither source has a spectrum consistent with a black hole binary in low/hard state, and both ULXs exhibit strong curvature in their broadband X-ray spectra. This curvature rules out models that invoke a simple reflection-dominated spectrum with a broadened iron line and no cutoff in the illuminating power-law continuum. X-ray spectrum of IC 342 X-1 can be characterized by a soft disk-like blackbody component at low energies and a cool, optically thick Comptonization continuum at high energies, but unique physical interpretation of the spectral components remains challenging. The broadband spectrum of IC 342 X-2 can be fit by either a hot (3.8 keV) accretion disk or a Comptonized continuum with no indication of a seed photon population. Although the seed photon component may be masked by soft excess emission unlikely to be associated with the binary system, combined with the high absorption column, it is more plausible that the broadband X-ray emission arises from a simple thin blackbody disk component. Secure identification of the origin of the spectral components in these sources will likely require broadband spectral variability studies.

  15. State-of-the-art X-ray photoelectron spectroscopy (XPS): Conventional and synchrotron x-ray sources for micro-XPS

    Energy Technology Data Exchange (ETDEWEB)

    Principe, E.L.; Odom, R.W. [Charles Evans and Associates, Redwood City, CA (United States); Johnson, A.L.; Ackermann, G.D.; Hussain, Z.; Padmore, H. [Lawrence Berkeley National Lab., CA (United States). Advanced Light Source

    1998-12-31

    This paper presents preliminary data on analyses of selected materials using two state-of-the-art XPS systems: the Physical Electronics Inc. (PHI, Eden Prairie, MN) Quantum 2000 instrument and the microXPS beamline (7.3.2.1) at the Advanced Light Source (ALS). This research compares and contrasts relevant performance characteristics of the two systems including elemental and chemical state detection sensitivity, imaging capabilities including lateral resolution and useful image fields, role of X-ray dose damage to surface, analysis speed as well as analytical throughput.

  16. XMM-Newton observation of the X-ray point source population of the starburst galaxy IC342

    CERN Document Server

    Kong, A

    2003-01-01

    We present the results of an XMM-Newton observation of the starburst galaxy IC342. Thirty-seven X-ray point sources were detected down to a luminosity limit of $\\sim 10^{37}$ \\lum. Most of the sources are located near the spiral arms. The X-ray point source luminosity function is consistent with a power-law shape with a slope of 0.55, typical of starburst galaxies. We also present the energy spectra of several ultraluminous X-ray sources (ULXs), including the luminous X-ray source in the galactic nucleus. Except for the nucleus and a luminous supersoft X-ray source, other ULXs can generally be fit with a simple power-law spectral model. The nucleus is very luminous ($\\sim 10^{40}$\\lum in 0.2-12 keV) and requires disc blackbody and power-law components to describe the X-ray emission. The spectral fit reveals a cool accretion disc (kT=0.11 keV) and suggests that the source harbours either an intermediate-mass black hole or a stellar-mass black hole with outflow.

  17. Measurement of x-ray energy spectrum by using HPGe detection in 14.5 GHz ECR ion source

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Cheol Ho; Chang, Dae Sik; Oh, Byung Hoon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Seo, Chang Seog; Kim, Yong Kyun [Institute for Basic Science, Daejeon (Korea, Republic of)

    2013-04-15

    The Electron Cyclotron Resonance (ECR) ion source is used to produce intense, high charge state ion beams of intermediate and heavy mass elements. It is widely used to produce ion beams for accelerator, atomic physics research and industrial application. The basic principle of the ECR ion source is the resonance absorption of energy by electron from microwave that has the same frequency as the electron's frequency in the resonance zone. The ECR ion source produces soft and hard x-rays because of efficient heating of electrons. The x-rays are created by electron-ion collisions in the ECR plasma or, when free electrons collide with ECR plasma chamber wall. The generated x-rays are influenced by various input parameters of the ECR ion source. In this study, The x-ray spectrum was measured by using a 14.5 GHz ECR ion source at Korea Atomic Energy Research Institute (KAERI). ECR ion source is used to generate ion beams of heavy mass elements. KAERI has a 14.5 GHz ECR ion source to produce high current ion beam. In this study, experimental condition is provided to generate stable plasma through x-ray spectrum measurement. In the future, x-rays spectra will be measured at various operation conditions such as gas-pressure, trim coil and solenoid current.

  18. Stereoscopic observations of hard x ray sources in solar flares made with GRO and other spacecraft

    Science.gov (United States)

    Kane, S. R.; Hurley, K.; Mctiernan, J. M.; Laros, J. G.

    1992-01-01

    Since the launch of the Gamma Ray Observatory (GRO) in Apr. 1991, the Burst and Transient Source Experiment (BATSE) instrument on GRO has recorded a large number of solar flares. Some of these flares have also been observed by the Gamma-Ray Burst Detector on the Pioneer Venus Orbiter (PVO) and/or by the Solar X-Ray/Cosmic Gamma-Ray Burst Experiment on the Ulysses spacecraft. A preliminary list of common flares observed during the period May-Jun. 1991 is presented and the possible joint studies are indicated.

  19. Effect of an x-ray source on the ion abundance of the upper atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Avakyan, S.V.

    1984-05-01

    The author considers the effect of a pulsed x-ray source on the production of doubly charged ions from atomic and molecular oxygen and molecular nitrogen, incorporating the Auger effect, at heights of 90-450 km in the earth's ionosphere. Calculations indicate that these ions make up approximately 5% at heights below 200-250km and several tens of percent at heights of 300-450km, with lifetimes between 0.1 and 1000 sec at heights of 190-450km.

  20. HST/ACS IMAGING OF OMEGA CENTAURI: OPTICAL COUNTERPARTS OF CHANDRA X-RAY SOURCES

    Energy Technology Data Exchange (ETDEWEB)

    Cool, Adrienne M.; Arias, Tersi; Brochmann, Michelle; Dorfman, Jason; Gafford, April; White, Vivian [Department of Physics and Astronomy, San Francisco State University, 1600 Holloway Avenue, San Francisco, CA 94132 (United States); Haggard, Daryl [Center for Interdisciplinary Exploration and Research in Astrophysics, Physics and Astronomy Department, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 (United States); Anderson, Jay, E-mail: cool@sfsu.edu, E-mail: dhaggard@northwestern.edu [Space Telescope Science Institute, Baltimore, MD 21218 (United States)

    2013-02-15

    We present results of a search for optical counterparts of X-ray sources in and toward the globular cluster Omega Centauri (NGC 5139) using the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope. The ACS data consist of a mosaic of Wide Field Channel images obtained using F625W, F435W, and F658N filters; with nine pointings we cover the central {approx}10' Multiplication-Sign 10' of the cluster and encompass 109 known Chandra sources. We find promising optical counterparts for 59 of the sources, {approx}40 of which are likely to be associated with the cluster. These include 27 candidate cataclysmic variables (CVs), 24 of which are reported here for the first time. Fourteen of the CV candidates are very faint, with absolute magnitudes in the range M {sub 625} =10.4-12.6, making them comparable in brightness to field CVs near the period minimum discovered in the Sloan Digital Sky Survey. Additional optical counterparts include three BY Dra candidates, a possible blue straggler, and a previously reported quiescent low-mass X-ray binary. We also identify 3 foreground stars and 11 probable active galactic nuclei. Finally, we report the discovery of a group of seven stars whose X-ray properties are suggestive of magnetically active binaries, and whose optical counterparts lie on or very near the metal-rich anomalous giant and subgiant branches in {omega} Cen. If the apparent association between these seven stars and the RGB/SGB-a stars is real, then the frequency of X-ray sources in this metal-rich population is enhanced by a factor of at least five relative to the other giant and subgiant populations in the cluster. If these stars are not members of the metal-rich population, then they bring the total number of red stragglers (also known as sub-subgiants) that have been identified in {omega} to Cen 20, the largest number yet known in any globular cluster.

  1. The flying mirror: future brightest x-ray and γ-ray source

    Science.gov (United States)

    Esirkepov, T. Z.; Bulanov, S. V.; Kando, M.; Pirozhkov, A. S.; Zhidkov, A. G.

    2009-05-01

    An ultra-bright high-power X-ray and γ-ray source is proposed. A relativistic flying mirror reflects a counterpropagating electromagnetic radiation causing its frequency multiplication and intensification, while the role of the mirror is played by a solid-density thin plasma slab accelerating in the radiation pressure dominant regime. Frequencies of high harmonics generated at the flying mirror by a relativistically strong counter-propagating radiation undergo multiplication with the same factor as the fundamental frequency of the reflected radiation, approximately equal to the quadruple of the square of the mirror Lorentz factor. The theory of the reflectivity of a moving thin plasma slab is presented.

  2. Optics for the lattice of the compact storage ring for a Compton X-ray source

    Institute of Scientific and Technical Information of China (English)

    YU Pei-Cheng; WANG Yu; SHEN Xiao-zhe; HUANG Wen-Hui; YAN Li-xin; DU Ying-Chao; LI Ren-Kai; TANG Chuan-Xiang

    2009-01-01

    We present two types of optics for the lattice of a compact storage ring for a Compton X-ray source.The optics design for different operation modes of the storage ring are discussed in detail.For the pulse mode optics,an IBS-suppression scheme is applied to optimize the optics for lower IBS emittance growth rate;as for the steady mode,the method to control momentum compact factor is adopted[Gladkikh P,Phys.Rev.ST Accel.Beams 8,050702]to obtain stability of the electron beam.

  3. Physiologically gated microbeam radiation using a field emission x-ray source array

    Energy Technology Data Exchange (ETDEWEB)

    Chtcheprov, Pavel, E-mail: PavelC@unc.edu, E-mail: zhou@email.unc.edu [Department of Biomedical Engineering, University of North Carolina, 152 MacNider Hall, Campus Box 7575, Chapel Hill, North Carolina 27599 (United States); Burk, Laurel; Inscoe, Christina; Ger, Rachel; Hadsell, Michael; Lu, Jianping [Department of Physics and Astronomy, University of North Carolina, Phillips Hall, CB #3255, 120 East Cameron Avenue, Chapel Hill, North Carolina 27599 (United States); Yuan, Hong [Department of Radiology, University of North Carolina, 2006 Old Clinic, CB #7510, Chapel Hill, North Carolina 27599 (United States); Zhang, Lei [Department of Applied Physical Sciences, University of North Carolina, Chapman Hall, CB#3216, Chapel Hill, North Carolina 27599 (United States); Chang, Sha [Department of Radiation Oncology, University of North Carolina, 101 Manning Drive, Chapel Hill, North Carolina 27514 and UNC Lineberger Comprehensive Cancer Center, University of North Carolina, 101 Manning Drive, Chapel Hill, North Carolina 27514 (United States); Zhou, Otto, E-mail: PavelC@unc.edu, E-mail: zhou@email.unc.edu [Department of Physics and Astronomy, University of North Carolina, Phillips Hall, CB #3255, 120 East Cameron Avenue, Chapel Hill, North Carolina 27599 and UNC Lineberger Comprehensive Cancer Center, University of North Carolina, 101 Manning Drive, Chapel Hill, North Carolina 27514 (United States)

    2014-08-15

    Purpose: Microbeam radiation therapy (MRT) uses narrow planes of high dose radiation beams to treat cancerous tumors. This experimental therapy method based on synchrotron radiation has been shown to spare normal tissue at up to 1000 Gy of peak entrance dose while still being effective in tumor eradication and extending the lifetime of tumor-bearing small animal models. Motion during treatment can lead to significant movement of microbeam positions resulting in broader beam width and lower peak to valley dose ratio (PVDR), which reduces the effectiveness of MRT. Recently, the authors have demonstrated the feasibility of generating microbeam radiation for small animal treatment using a carbon nanotube (CNT) x-ray source array. The purpose of this study is to incorporate physiological gating to the CNT microbeam irradiator to minimize motion-induced microbeam blurring. Methods: The CNT field emission x-ray source array with a narrow line focal track was operated at 160 kVp. The x-ray radiation was collimated to a single 280 μm wide microbeam at entrance. The microbeam beam pattern was recorded using EBT2 Gafchromic{sup ©} films. For the feasibility study, a strip of EBT2 film was attached to an oscillating mechanical phantom mimicking mouse chest respiratory motion. The servo arm was put against a pressure sensor to monitor the motion. The film was irradiated with three microbeams under gated and nongated conditions and the full width at half maximums and PVDRs were compared. An in vivo study was also performed with adult male athymic mice. The liver was chosen as the target organ for proof of concept due to its large motion during respiration compared to other organs. The mouse was immobilized in a specialized mouse bed and anesthetized using isoflurane. A pressure sensor was attached to a mouse's chest to monitor its respiration. The output signal triggered the electron extraction voltage of the field emission source such that x-ray was generated only

  4. Physiologically gated microbeam radiation using a field emission x-ray source array.

    Science.gov (United States)

    Chtcheprov, Pavel; Burk, Laurel; Yuan, Hong; Inscoe, Christina; Ger, Rachel; Hadsell, Michael; Lu, Jianping; Zhang, Lei; Chang, Sha; Zhou, Otto

    2014-08-01

    Microbeam radiation therapy (MRT) uses narrow planes of high dose radiation beams to treat cancerous tumors. This experimental therapy method based on synchrotron radiation has been shown to spare normal tissue at up to 1000 Gy of peak entrance dose while still being effective in tumor eradication and extending the lifetime of tumor-bearing small animal models. Motion during treatment can lead to significant movement of microbeam positions resulting in broader beam width and lower peak to valley dose ratio (PVDR), which reduces the effectiveness of MRT. Recently, the authors have demonstrated the feasibility of generating microbeam radiation for small animal treatment using a carbon nanotube (CNT) x-ray source array. The purpose of this study is to incorporate physiological gating to the CNT microbeam irradiator to minimize motion-induced microbeam blurring. The CNT field emission x-ray source array with a narrow line focal track was operated at 160 kVp. The x-ray radiation was collimated to a single 280 μm wide microbeam at entrance. The microbeam beam pattern was recorded using EBT2 Gafchromic(©) films. For the feasibility study, a strip of EBT2 film was attached to an oscillating mechanical phantom mimicking mouse chest respiratory motion. The servo arm was put against a pressure sensor to monitor the motion. The film was irradiated with three microbeams under gated and nongated conditions and the full width at half maximums and PVDRs were compared. An in vivo study was also performed with adult male athymic mice. The liver was chosen as the target organ for proof of concept due to its large motion during respiration compared to other organs. The mouse was immobilized in a specialized mouse bed and anesthetized using isoflurane. A pressure sensor was attached to a mouse's chest to monitor its respiration. The output signal triggered the electron extraction voltage of the field emission source such that x-ray was generated only during a portion of the mouse

  5. High-resolution soft X-ray beamline ADRESS at the Swiss Light Source for resonant inelastic X-ray scattering and angle-resolved photoelectron spectroscopies

    Energy Technology Data Exchange (ETDEWEB)

    Strocov, V. N., E-mail: vladimir.strocov@psi.ch; Schmitt, T.; Flechsig, U.; Schmidt, T.; Imhof, A.; Chen, Q.; Raabe, J. [Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen-PSI (Switzerland); Betemps, R.; Zimoch, D.; Krempasky, J. [Paul Scherrer Institut, CH-5232 Villigen-PSI (Switzerland); Wang, X. [Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen-PSI (Switzerland); Institut de Physique de la Matiére Condensé, Ecole Polytechnique Fédéderale de Lausanne (Switzerland); Grioni, M. [Institut de Physique de la Matiére Condensé, Ecole Polytechnique Fédéderale de Lausanne (Switzerland); Piazzalunga, A. [Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen-PSI (Switzerland); Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano (Italy); Patthey, L. [Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen-PSI (Switzerland)

    2010-09-01

    Concepts and technical realization of the high-resolution soft X-ray beamline ADRESS at the Swiss Light Source are described. Optimization of the optical scheme for high resolution and photon flux as well as diagnostics tools and alignment strategies are discussed. The concepts and technical realisation of the high-resolution soft X-ray beamline ADRESS operating in the energy range from 300 to 1600 eV and intended for resonant inelastic X-ray scattering (RIXS) and angle-resolved photoelectron spectroscopy (ARPES) are described. The photon source is an undulator of novel fixed-gap design where longitudinal movement of permanent magnetic arrays controls not only the light polarization (including circular and 0–180° rotatable linear polarizations) but also the energy without changing the gap. The beamline optics is based on the well established scheme of plane-grating monochromator operating in collimated light. The ultimate resolving power E/ΔE is above 33000 at 1 keV photon energy. The choice of blazed versus lamellar gratings and optimization of their profile parameters is described. Owing to glancing angles on the mirrors as well as optimized groove densities and profiles of the gratings, the beamline is capable of delivering high photon flux up to 1 × 10{sup 13} photons s{sup −1} (0.01% BW){sup −1} at 1 keV. Ellipsoidal refocusing optics used for the RIXS endstation demagnifies the vertical spot size down to 4 µm, which allows slitless operation and thus maximal transmission of the high-resolution RIXS spectrometer delivering E/ΔE > 11000 at 1 keV photon energy. Apart from the beamline optics, an overview of the control system is given, the diagnostics and software tools are described, and strategies used for the optical alignment are discussed. An introduction to the concepts and instrumental realisation of the ARPES and RIXS endstations is given.

  6. X-ray Sources and Their Optical Counterparts in the Galactic Globular Cluster M12 (NGC 6218)

    CERN Document Server

    Lu, Ting-Ni; Bassa, Cees; Verbunt, Frank; Lewin, Walter H G; Anderson, Scott F; Pooley, David

    2009-01-01

    We study a Chandra X-ray Observatory ACIS-S observation of the Galactic globular cluster M12. With a 26 ks exposure time, we detect 6 X-ray sources inside the half-mass radius (2'.16) and two of them are inside the core radius (0'.72) of the cluster. If we assume these sources are all within the globular cluster M12, the luminosity Lx among these sources between 0.3-7.0 keV varies roughly from 10^30 to 10^32 ergs s^-1. For identification, we also analyzed the Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) data and identified the optical counterparts to five X-ray sources inside the HST field of view. According to the X-ray and optical features, we found 2-5 candidate active binaries (ABs) or cataclysmic variables (CVs) and 0-3 background galaxies within the HST ACS field of view. Based on the assumption that the number of X-ray sources scales with the encounter rate and the mass of the globular cluster, we expect 2 X-ray source inside M12, and the expectation is consistent with our observation...

  7. Beamline X29: a novel undulator source for X-ray crystallography.

    Science.gov (United States)

    Shi, Wuxian; Robinson, Howard; Sullivan, Michael; Abel, Don; Toomey, John; Berman, Lonny E; Lynch, Don; Rosenbaum, Gerd; Rakowsky, George; Rock, Larry; Nolan, Bill; Shea-McCarthy, Grace; Schneider, Dieter; Johnson, Erik; Sweet, Robert M; Chance, Mark R

    2006-09-01

    A high-flux insertion device and beamline for macromolecular crystallography has been built at the National Synchrotron Light Source (NSLS) that employs a mini-gap undulator source developed by the NSLS. The mini-gap undulator at beamline X29 is a hybrid-magnet device of period 12.5 mm operating at proven gaps of 3.3-10 mm. The beamline provides hard X-rays for macromolecular crystallography experiments from the second and third harmonics over an energy range of 5-15 keV. The X-ray optics is designed to deliver intense and highly collimated X-rays. Horizontal focusing is achieved by a cryogenically cooled sagittally focusing double-crystal monochromator with approximately 4.1:1 demagnification. A vertical focusing mirror downstream of the monochromator is used for harmonic rejection and vertical focusing. The experimental station hosts an Area Detector Systems Quantum 315 CCD detector with 2.2 s readout time between exposures and Crystal Logic goniostat for crystal rotation and detector positioning. An auto-mounter crystal changer has been installed to facilitate the high-throughput data collection required by the major users, which includes structural genomics projects and the Macromolecular Crystallography Research Resource mail-in program. X29 is 10(3) times brighter than any existing bending-magnet beamline at NSLS with an actual flux of 2.5 x 10(11) photons s(-1) through a 0.12 mm square aperture at 11.271 keV.

  8. Alignment and Testing of a Telecentric Zoom Lens Used for the Cygnus X-ray Source

    Energy Technology Data Exchange (ETDEWEB)

    Malone, R. M. [NSTec; Baker, S. A. [NSTec; Brown, K. K. [NSTec; Castaneda, J. J. [NSTec; Curtis, A. H. [NSTec; Danielson, J. [NSTec; Droemer, D. W. [NSTec; Esquibel, D. L. [NSTec; Haines, T. J. [LANL; Hollabaugh, J. S. [NSTec; Howe, R. A. [NSTec; Huerta, J. A. [NSTec; King, N. S. P. [LANL; Lutz, S. S. [NSTec; Kaufman, M. I. [NSTec; McGillivray, K. D. [NSTec; Smith, A. D. [NSTec; Stokes, B. M. [NSTec; Tibbitts, A. [NSTec

    2013-09-01

    Cygnus is a high-energy radiographic x-ray source. Three large zoom lenses have been assembled to collect images from large scintillators. A large elliptical pellicle (394 × 280 mm) deflects the scintillator light out of the x-ray path into an eleven-element zoom lens coupled to a CCD camera. The zoom lens and CCD must be as close as possible to the scintillator to maximize light collection. A telecentric lens design minimizes image blur from a volume source. To maximize the resolution of objects of different sizes, the scintillator and zoom lens are translated along the x-ray axis, and the zoom lens magnification changes. Zoom magnification is also changed when different-sized recording cameras are used (50 or 62 mm square format). The LYSO scintillator measures 200 × 200 mm and is 5 mm thick. The scintillator produces blue light peaking at 435 nm, so special lens materials are required. By swapping out one doublet and allowing all other lenses to be repositioned, the zoom lens can also use a CsI(Tl) scintillator that produces green light centered at 540 nm (for future operations). All lenses have an anti-reflective coating for both wavelength bands. Two sets of doublets, the stop, the scintillator, and the CCD camera move during zoom operations. One doublet has x-y compensation. Alignment of the optical elements was accomplished using counter propagating laser beams and monitoring the retro-reflections and steering collections of laser spots. Each zoom lens uses 60 lb of glass inside the 425 lb mechanical structure, and can be used in either vertical or horizontal orientation.

  9. ALS-II, a Potential Soft X-ray, Diffraction Limited Upgrade of the Advanced Light Source

    Science.gov (United States)

    Tarawneh, H.; Steier, C.; Falcone, R.; Robin, D.; Nishimura, H.; Sun, C.; Wan, W.

    2014-03-01

    The Advanced Light Source (ALS) at Berkeley Lab has seen many upgrades over the years, keeping it one of the brightest sources for soft x-rays worldwide. Recent developments in magnet technology and lattice design appear to open the door for very large further increases in brightness [1], particularly by reducing the horizontal emittance, even within the space constraints of the existing tunnel. Initial studies for possible lattices will be presented that could approach the soft x-ray diffraction limit around 2 keV in both planes within the ALS footprint. Emerging scientific applications and experimental methods that would greatly benefit from ring based sources having much higher brightness and transverse coherence than present or near future storage ring facilities include nanometer imaging applications, X-ray correlation spectroscopy, diffraction microscopy, holography, ptychography, and resonant inelastic soft X-ray scattering at high resolution.

  10. HST/ACS Imaging of Omega Centauri: Optical Counterparts of Chandra X-Ray Sources

    CERN Document Server

    Cool, Adrienne M; Arias, Tersi; Brochmann, Michelle; Dorfman, Jason; Gafford, April; White, Vivian; Anderson, Jay

    2012-01-01

    We present results of a search for optical counterparts of X-ray sources in and toward the globular cluster Omega Centauri (NGC 5139) using the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope. The ACS data consist of a mosaic of Wide Field Channel (WFC) images obtained using F625W, F435W, and F658N filters; with 9 pointings we cover the central ~10'x10' of the cluster and encompass 109 known Chandra sources. We find promising optical counterparts for 59 of the sources, ~40 of which are likely to be associated with the cluster. These include 27 candidate cataclysmic variables (CVs), 24 of which are reported here for the first time. Fourteen of the CV candidates are very faint, with absolute magnitudes in the range M_625 = 10.4 - 12.6, making them comparable in brightness to field CVs near the period minimum discovered in the SDSS (Gansicke et al. 2009). Additional optical counterparts include three BY Dra candidates, a possible blue straggler, and a previously-reported quiescent low-mass X-ray ...

  11. Synchrotron soft X-ray and field-emission electron sources: a comparison.

    Science.gov (United States)

    Spence, J C H; Howells, M R

    2002-12-01

    The soft X-ray spectral region and the useful range of electron energy-loss spectroscopy are very similar, both including the energy range 100-1000 eV. Moreover, well-developed monochromators and parallel detection devices with comparable resolution exist for both. Despite the differing interactions of electrons and photons, many complementary experiments in imaging, spectroscopy and diffraction have been performed using both techniques. We therefore compare the brightness, degeneracy, monochromaticity, beam size, source size, spatial and temporal coherence of field-emission electron beams and soft X-ray synchrotron radiation from typical undulators. Recent brightness values for nanotip field emitters and undulators, both measured and calculated, are provided with examples from the Advanced Light Source synchrotron-radiation facility at Berkeley USA. The quantum mechanical upper limit on source brightness, as well as relationships among beam brightness, coherence parameters, and degeneracy, are discussed. Factors which limit these parameters and methods of measurement are reviewed, and the implications for diffraction, imaging and spectroscopic experiments as well as radiation damage are briefly commented on.

  12. The Einstein Observatory catalog of IPC x ray sources. Volume 1E: Documentation

    Science.gov (United States)

    Harris, D. E.; Forman, W.; Gioia, I. M.; Hale, J. A.; Harnden, F. R., Jr.; Jones, C.; Karakashian, T.; Maccacaro, T.; Mcsweeney, J. D.; Primini, F. A.

    1993-01-01

    The Einstein Observatory (HEAO-2, launched November 13, 1978) achieved radically improved sensitivity over previous x-ray missions through the use of focusing optics, which simultaneously afforded greatly reduced background and produced true images. During its 2.5-yr mission, the Einstein X-Ray Telescope was pointed toward some 5,000 celestial targets, most of which were detected, and discovered several thousand additional 'serendipitous' sources in the observed fields. This catalog contains contour diagrams and source data, obtained with the imaging proportional counter in the 0.16 to 3.5 keV energy band, and describes methods for recovering upper limits for any sky position within the observed images. The main catalog consists of six volumes (numbered 2 through 7) of right ascension ordered pages, each containing data for one observation. Along with the primary documentation describing how the catalog was constructed, volume 1 contains a complete source list, results for merged fields, a reference system to published papers, and data useful for calculating upper limits and fluxes.

  13. Spectral and timing characterization of the X-ray source 1RXS J194211.9+255552

    CERN Document Server

    D'Aì, A; La Parola, V; Segreto, A

    2016-01-01

    We report on the first spectral and timing characterization of the transient X-ray source 1RXS J194211.9+255552 using all available data from the Swift X-ray satellite. We used 10 years of hard X-ray data from the Burst Alert Telescope (BAT) to characterize its long-term behaviour and to search for long periodicities, finding evidence for a periodic modulation at 166.5 $\\pm$ 0.5 d, that we interpret as the orbital period of the source. The folded light curve reveals that the X-ray emission is mostly concentrated in a restricted phase-interval and we propose to associate 1RXS J194211.9+255552 to the class of the Be X-ray binaries. This is also supported by the results of the spectral analysis, where we used the BAT data and three pointed Swift/XRT observations to characterize the X-ray broad-band spectral shape. We found mild spectral variability in soft X-rays that can be accounted for by a varying local neutral absorber, while the intrinsic emission is consistent with a hard power law multiplied by a high-en...

  14. Neutron star population in the Galactic center region as a potential source of polarized X-ray emission

    Science.gov (United States)

    Zajacek, Michal; Karas, Vladimir; Eckart, Andreas

    2016-06-01

    We analyse the emission properties of neutron stars that are predicted to exist in large numbers of the order of 10000 in the innermost parts of the Galactic center. A part of the population of isolated neutron stars propagates supersonically through denser ionized streams of the Minispiral (Sgr A West), forming bow shocks where particles are accelerated and are expected to produce polarized X-ray synchrotron signal. Another source of the synchrotron emission is an elongated magnetosphere and tail. We investigate whether the polarized X-ray emission from Galactic center neutron stars will be potentially detectable in the framework of future X-ray polarimeters. A special case is a detected young neutron star - magnetar SGRJ1745-2900 - that has undergone a series of outbursts with a peak X-ray luminosity of the order of 10^{35} erg s^{-1} (1-10 keV). Apart from an intrinsic X-ray emission, the X-ray emission from neutron star outbursts may be scattered by molecular clouds in the Central Molecular Zone by Thomson scattering, which is another potential source of polarized X-ray emission.

  15. Performance Optimization of a High-Repetition-Rate KrF Laser Plasma X-Ray Source for Microlithography.

    Science.gov (United States)

    Bukerk, F; Louis, E; Turcu, E C; Tallents, G J; Batani, D

    1992-01-01

    In order to develop a high-intensity laser plasma x-ray source appropriate for industrial application of x-ray lithography, experiments have been carried out using a high-repetition-rate (up to 40 Hz) excimer laser (249 nm, 300 mJ) with a power density of 2 × 1013 W/ cm2 in the laser focus. In this study emphasis is given to remedying specific problems inherent in operating the laser plasma x-ray source at high repetition rates and in its prolonged operation. Two different methods of minimizing the production of target debris are investigated. First, the use of helium as a quenching gas results in a reduction of the amount of atomic debris particles by more than two orders of magnitude with negligible x-ray absorption. Second, a tape target as opposed to a solid target reduces the production of larger debris particles by a further factor of 100. Remaining debris is stopped by an aluminized plastic or beryllium filter used to avoid exposure of the resist by plasma ultraviolet radiation. The x-ray source has been used to image x-ray transmission mask structures down to 0.3 μm onto general purpose x-ray photo-resist. Results have been analyzed with SEM. The x-ray emission spectrum of the repetitive laser plasmas created from an iron target has been recorded and the conversion efficiency of the laser light into x-rays that contribute to exposure of the resist was measured to be 0.3% over 2π sr.

  16. New Hubble Space Telescope imaging of the counterparts to six ultraluminous X-ray sources

    CERN Document Server

    Roberts, T P; Goad, M R

    2008-01-01

    We report the results of new Hubble Space Telescope imaging of the positions of six ultraluminous X-ray sources (ULXs). Using images in three ACS filters we detect good candidate counterparts to four out of six ULXs, with one more possible detection, and observed magnitudes in the range m ~ 22 - 26 in the F606W filter. The extinction-corrected colours and absolute magnitudes vary from source to source, even after correcting for additional extinction in the host galaxy, and only one counterpart is readily explained as an OB star. Nevertheless, these counterparts are decent candidates for future follow-up in pursuit of dynamical mass constraints on the likely black holes powering these sources.

  17. Ways of development of compact coherent femtosecond X-ray sources for applications in nano- and biophotonics

    Science.gov (United States)

    Mikheev, L.

    2017-01-01

    Ways of the development of compact coherent sources of soft X-ray femtosecond pulses are discussed, which meet the requirements for the implementation of the “diffraction-before-destruction” approach in the lensless X-ray Coherent Diffractive Imaging (CDI) technique enabling quantitative 3D mapping of material structure with the nanoscale spatial resolution. An innovative hybrid (solid/gas) approach to produce ultra-intense femtosecond laser pulses in the visible is described in the context of its applications for laser driven high harmonic generation (HHG) and soft X-ray generation in laser plasmas due to recombination mechanism of excitation.

  18. Spatiotemporal stability of a femtosecond hard-x-ray undulator source studied by control of coherent optical phonons.

    Science.gov (United States)

    Beaud, P; Johnson, S L; Streun, A; Abela, R; Abramsohn, D; Grolimund, D; Krasniqi, F; Schmidt, T; Schlott, V; Ingold, G

    2007-10-26

    We report on the temporal and spatial stability of the first tunable femtosecond undulator hard-x-ray source for ultrafast diffraction and absorption experiments. The 2.5-1 Angstrom output radiation is driven by an initial 50 fs laser pulse employing the laser-electron slicing technique. By using x-ray diffraction to probe laser-induced coherent optical phonons in bulk bismuth, we estimate an x-ray pulse duration of 140+/-30 fs FWHM with timing drifts below 30 fs rms measured over 5 days. Optical control of coherent lattice motion is demonstrated.

  19. Investigating ChaMPlane X-ray sources in the Galactic Bulge with Magellan LDSS2 spectra

    OpenAIRE

    Koenig, Xavier; Grindlay, Jonathan E.; Berg, Maureen van den; Laycock, Silas; Zhao, Ping; Hong, Jaesub; Schlegel, Eric M.

    2008-01-01

    We have carried out optical and X-ray spectral analyses on a sample of 136 candidate optical counterparts of X-ray sources found in five Galactic-bulge fields included in our Chandra Multi-wavelength Plane Survey. We use a combination of optical spectral fitting and quantile X-ray analysis to obtain the hydrogen column density towards each object, and a three-dimensional dust model of the Galaxy to estimate the most probable distance in each case. We present the discovery of a population of s...

  20. V723 Cassiopeia still on in X-rays: A bright Super Soft Source 12 years after outburst

    CERN Document Server

    Ness, J U-; Starrfield, S; Osborne, J P; Page, K L; Beardmore, A P; Wagner, R M; Woodward, C E

    2008-01-01

    We find that the classical nova V723 Cas (1995) is still an active X-ray source more than 12 years after outburst and analyze seven X-ray observations carried out with Swift between 2006 January 31 and 2007 December 3. The average count rate is 0.022+/-0.01 cts s^{-1} but the source is variable within a factor of two of the mean and does not show any signs of turning off. We present supporting optical observations which show that between 2001 and 2006 an underlying hot source was present with steadily increasing temperature. In order to confirm that the X-ray emission is from V723 Cas, we extract a ROSAT observation taken in 1990 and find that there was no X-ray source at the position of the nova. The Swift XRT spectra resemble those of the Super Soft X-ray binary Sources (SSS) which is confirmed by RXTE survey data which show no X-ray emission above 2 keV between 1996 and 2007. Using blackbody fits we constrain the effective temperature to between T_eff=(2.6-4.6)x10^5 K and a bolometric luminosity >5x10^35 e...