Science.gov

Sample records for 4th generation x-ray

  1. X-ray generator

    DOEpatents

    Dawson, John M.

    1976-01-01

    Apparatus and method for producing coherent secondary x-rays that are controlled as to direction by illuminating a mixture of high z and low z gases with an intense burst of primary x-rays. The primary x-rays are produced with a laser activated plasma, and these x-rays strip off the electrons of the high z atoms in the lasing medium, while the low z atoms retain their electrons. The neutral atoms transfer electrons to highly excited states of the highly striped high z ions giving an inverted population which produces the desired coherent x-rays. In one embodiment, a laser, light beam provides a laser spark that produces the intense burst of coherent x-rays that illuminates the mixture of high z and low z gases, whereby the high z atoms are stripped while the low z ones are not, giving the desired mixture of highly ionized and neutral atoms. To this end, the laser spark is produced by injecting a laser light beam, or a plurality of beams, into a first gas in a cylindrical container having an adjacent second gas layer co-axial therewith, the laser producing a plasma and the intense primary x-rays in the first gas, and the second gas containing the high and low atomic number elements for receiving the primary x-rays, whereupon the secondary x-rays are produced therein by stripping desired ions in a neutral gas and transfer of electrons to highly excited states of the stripped ions from the unionized atoms. Means for magnetically confining and stabilizing the plasma are disclosed for controlling the direction of the x-rays.

  2. Electromechanical x-ray generator

    DOEpatents

    Watson, Scott A; Platts, David; Sorensen, Eric B

    2016-05-03

    An electro-mechanical x-ray generator configured to obtain high-energy operation with favorable energy-weight scaling. The electro-mechanical x-ray generator may include a pair of capacitor plates. The capacitor plates may be charged to a predefined voltage and may be separated to generate higher voltages on the order of hundreds of kV in the AK gap. The high voltage may be generated in a vacuum tube.

  3. Electron beam parallel X-ray generator

    NASA Technical Reports Server (NTRS)

    Payne, P.

    1967-01-01

    Broad X ray source produces a highly collimated beam of low energy X rays - a beam with 2 to 5 arc minutes of divergence at energies between 1 and 6 keV in less than 5 feet. The X ray beam is generated by electron bombardment of a target from a large area electron gun.

  4. Flywheel-powered X-ray generator

    NASA Technical Reports Server (NTRS)

    Siedband, M. P.

    1984-01-01

    The use of a small flywheel appears to be a practical alternative to other power sources for mobile X-ray system applications. A 5 kg flywheel has been constructed which runs at 10 krpm and stores 30 KJ while requiring less than 500 W to bring the system up to speed. The wheel is coupled to an aircraft alternator and can yield pulsed power levels over 50 KWp. The aircraft alternator has the advantage of high frequency output which has also permitted the design of smaller high voltage transformers. A series of optical sensors detecting shaft position function as an electronic commutator so that the alternator may operate as a motor to bring the wheel up to operating speed. The system permits the generation of extremely powerful X-rays from a variety of low power sources such as household power outlets, automobile batteries or sources of poorly regulated electrical power such as those found in third world countries.

  5. Next Generation X-ray Polarimeter

    NASA Astrophysics Data System (ADS)

    Hill-Kittle, Joe

    The emission regions of many types of X-ray sources are small and cannot be spatially resolved without interferometry techniques that haven't yet been developed. In order to understand the emission mechanisms and emission geometry, alternate measurement techniques are required. Most microphysical processes that affect X-rays, including scattering and magnetic emission processes are imprinted as polarization signatures. X-ray polarization also reveals exotic physical processes occurring in regions of very strong gravitational and magnetic fields. Observations of X-ray polarization will provide a measurement of the geometrical distribution of gas and magnetic fields without foreground depolarization that affects longer wavelengths (e.g. Faraday rotation in the radio). Emission from accretion disks has an inclination-dependent polarization. The polarization signature is modified by extreme gravitational forces, which bend light, essentially changing the contribution of each part of the disk to the integrated total intensity seen by distant observers. Because gravity has the largest effect on the innermost parts of the disk (which are the hottest, and thus contributes to more high energy photons), the energy dependent polarization is diagnostic of disk inclination, black hole mass and spin. Increasing the sensitive energy band will make these measurements possible. X-ray polarimetry will also enable the study of the origin of cosmic rays in the universe, the nature of black holes, the role of black holes in the evolution of galaxies, and the interaction of matter with the highest physically possible magnetic fields. These objectives address NASA's strategic interest in the origin, structure, and evolution of the universe. We propose a two-year effort to develop the Next Generation X-ray Polarimeter (NGXP) that will have more than ten times the sensitivity of the current state of the art. NGXP will make possible game changing measurements of classes of astrophysical

  6. Mobile X-ray generators: a review.

    PubMed

    Evans, S A; Harris, L; Lawinski, C P; Hendra, I R

    1985-01-01

    Mobile X-ray generators vary widely in design, cost and radiographic performance and the new designs of recent years have led to the introduction of jargon. Such terms as 'capacitator discharge' and 'modicum frequency' can give rise to confusion regarding operating technique. This review classifies the mobiles into three distinct categories. Simple rules are presented to enable an operator to transfer exposure factors from one category to another, and an analysis of the relative merits of each category is provided. Part 1 provides a description of the categories available, a broad explanation of the principles involved and discusses the radiographic use. Throughout the text certain terms are given in italics when first used in that particular description and Part 2 gives full explanations of these terms in the context of Part 1.

  7. Characteristic X-ray Generator Utilizing Angle Dependence of Bremsstrahlung X-ray Distribution

    NASA Astrophysics Data System (ADS)

    Sato, Eiichi; Tanaka, Etsuro; Mori, Hidezo; Kawai, Toshiaki; Inoue, Takashi; Ogawa, Akira; Sato, Shigehiro; Takayama, Kazuyoshi; Onagawa, Jun

    2006-04-01

    This generator consists of the following components: a constant high-voltage power supply, a filament power supply, a turbomolecular pump, and an X-ray tube. The X-ray tube is a demountable diode which is connected to the turbomolecular pump and consists of the following major devices: a molybdenum rod target, a tungsten hairpin cathode (filament), a focusing (Wehnelt) electrode, a polyethylene terephthalate X-ray window 0.25 mm in thickness, and a stainless-steel tube body. In the X-ray tube, the positive high voltage is applied to the anode (target) electrode, and the cathode is connected to the tube body (ground potential). In this experiment, the tube voltage applied was from 22 to 36 kV, and the tube current was regulated to within 100 μA by the filament temperature. The exposure time is controlled in order to obtain optimum X-ray intensity. The electron beams from the cathode are converged to the target by the focusing electrode, and clean K-series characteristic X-rays are produced through the focusing electrode without using a filter. The X-ray intensity was 26.6 μGy/s at 1.0 m from the X-ray source with a tube voltage of 30 kV and a tube current of 100 μA, and quasi-monochromatic radiography was performed using a computed radiography system.

  8. Monochromatic x-ray generator utilizing angle dependence of bremsstrahlung x-ray distribution

    NASA Astrophysics Data System (ADS)

    Sato, Eiichi; Tanaka, Etsuro; Mori, Hidezo; Kawai, Toshiaki; Inoue, Takashi; Ogawa, Akira; Ichimaru, Toshio; Takayama, Kazuyoshi; Ido, Hideaki

    2005-08-01

    This generator consists of the following components: a constant high-voltage power supply, a filament power supply, a turbomolecular pump, and an x-ray tube. The x-ray tube is a demountable diode which is connected to the turbomolecular pump and consists of the following major devices: a molybdenum rod target, a tungsten hairpin cathode (filament), a focusing (Wehnelt) electrode, a polyethylene terephthalate x-ray window 0.25 mm in thickness, and a stainless-steel tube body. In the x-ray tube, the positive high voltage is applied to the anode (target) electrode, and the cathode is connected to the tube body (ground potential). In this experiment, the tube voltage applied was from 22 to 36 kV, and the tube current was regulated to within 100 μA by the filament temperature. The exposure time is controlled in order to obtain optimum x-ray intensity. The electron beams from the cathode are converged to the target by the focusing electrode, and clean Kα rays are produced through the focusing electrode using a 20-μm-thick zirconium filter. The x-ray intensity was 12.1 μGy/s at 1.0 m from the x-ray source with a tube voltage of 30 kV and a tube current of 100 μA, and monochromatic radiography was performed using a computed radiography system.

  9. Apparatus for generating x-ray holograms

    DOEpatents

    Rhodes, Charles K.; Boyer, Keith; Solem, Johndale C.; Haddad, Waleed S.

    1990-01-01

    Apparatus for x-ray microholography of living biological materials. A Fourier transform holographic configuration is described as being most suitable for the 3-dimensional recording of the physical characteristics of biological specimens. The use of a spherical scatterer as a reference and a charge-coupled device two-dimensional detector array placed in the forward direction relative to the incident x-radiation for viewing electromagnetic radiation simultaneously scattered from both the specimen and the reference scatterer permits the ready reconstruction of the details of the specimen from the fringe pattern detected by the charge-coupled device. For example, by using a nickel reference scatter at 4.5 nm, sufficient reference illumination is provided over a wide enough angle to allow similar resolution in both transverse and longitudinal directions. Both laser and synchrotron radiation sources are feasible for generating microholographs. Operation in the water window (2.4 to 4.5 nm) should provide maximum contrast for features of the specimen and spatial resolution on the order of the wavelength of x-radiation should be possible in all three dimensions, which is sufficient for the visualization of many biological features. It is anticipated that the present apparatus will find utility in other areas as well where microscopic physical details of a specimen are important. A computational procedure which enables the holographic data collected by the detector to be used to correct for misalignments introduced by inexact knowledge of the relative positions of the spherical reference scatterer and the sample under investigation has been developed. If the correction is performed prior to reconstruction, full compensation can be achieved and a faithfully reconstructed image produced.

  10. Apparatus for generating x-ray holograms

    DOEpatents

    Rhodes, C.K.; Boyer, K.; Solem, J.C.; Haddad, W.S.

    1990-09-11

    Apparatus for x-ray microholography of living biological materials. A Fourier transform holographic configuration is described as being most suitable for the 3-dimensional recording of the physical characteristics of biological specimens. The use of a spherical scatterer as a reference and a charge-coupled device two-dimensional detector array placed in the forward direction relative to the incident x-radiation for viewing electromagnetic radiation simultaneously scattered from both the specimen and the reference scatterer permits the ready reconstruction of the details of the specimen from the fringe pattern detected by the charge-coupled device. For example, by using a nickel reference scatter at 4.5 nm, sufficient reference illumination is provided over a wide enough angle to allow similar resolution in both transverse and longitudinal directions. Both laser and synchrotron radiation sources are feasible for generating microholographs. Operation in the water window (2.4 to 4.5 nm) should provide maximum contrast for features of the specimen and spatial resolution on the order of the wavelength of x-radiation should be possible in all three dimensions, which is sufficient for the visualization of many biological features. It is anticipated that the present apparatus will find utility in other areas as well where microscopic physical details of a specimen are important. A computational procedure which enables the holographic data collected by the detector to be used to correct for misalignments introduced by inexact knowledge of the relative positions of the spherical reference scatterer and the sample under investigation has been developed. If the correction is performed prior to reconstruction, full compensation can be achieved and a faithfully reconstructed image produced. 7 figs.

  11. X-ray generation using carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Parmee, Richard J.; Collins, Clare M.; Milne, William I.; Cole, Matthew T.

    2015-01-01

    Since the discovery of X-rays over a century ago the techniques applied to the engineering of X-ray sources have remained relatively unchanged. From the inception of thermionic electron sources, which, due to simplicity of fabrication, remain central to almost all X-ray applications, there have been few fundamental technological advances. However, with the emergence of ever more demanding medical and inspection techniques, including computed tomography and tomosynthesis, security inspection, high throughput manufacturing and radiotherapy, has resulted in a considerable level of interest in the development of new fabrication methods. The use of conventional thermionic sources is limited by their slow temporal response and large physical size. In response, field electron emission has emerged as a promising alternative means of deriving a highly controllable electron beam of a well-defined distribution. When coupled to the burgeoning field of nanomaterials, and in particular, carbon nanotubes, such systems present a unique technological opportunity. This review provides a summary of the current state-of-the-art in carbon nanotube-based field emission X-ray sources. We detail the various fabrication techniques and functional advantages associated with their use, including the ability to produce ever smaller electron beam assembles, shaped cathodes, enhanced temporal stability and emergent fast-switching pulsed sources. We conclude with an overview of some of the commercial progress made towards the realisation of an innovative and disruptive technology.

  12. Multilayers for next generation x-ray sources

    SciTech Connect

    Bajt, S; Chapman, H N; Spiller, E; Hau-Riege, S; Alameda, J; Nelson, A J; Walton, C C; Kjornrattanawanich, B; Aquila, A; Dollar, F; Gullikson, E; Tarrio, C

    2007-05-04

    Multilayers are artificially layered structures that can be used to create optics and optical elements for a broad range of x-ray wavelengths, or can be optimized for other applications. The development of next generation x-ray sources (synchrotrons and x-ray free electron lasers) requires advances in x-ray optics. Newly developed multilayer-based mirrors and optical elements enabled efficient band-pass filtering, focusing and time resolved measurements in recent FLASH (Free Electron LASer in Hamburg) experiments. These experiments are providing invaluable feedback on the response of the multilayer structures to high intensity, short pulsed x-ray sources. This information is crucial to design optics for future x-ray free electron lasers and to benchmark computer codes that simulate damage processes.

  13. Atomic tungsten for ultrafast hard X-ray generation.

    PubMed

    Shan, Fang; Couch, Vernon A; Guo, Ting

    2005-05-19

    High-resolution X-ray absorption measurements (with an accuracy of +/-0.3 eV) of ZnSO(4) (aq) were performed with ultrafast selected energy X-ray absorption spectroscopy (USEXAS) using a laser-driven tungsten target X-ray source. The results were used to determine the absolute spectral positions of characteristic emission lines. By comparing these positions to those predicted for the line emission from tungsten of different oxidation states using the Dirac-Fock formula, the tungsten species responsible for ultrafast hard X-ray generation were found to be tungsten atoms. This finding provides the first direct evidence to support the mechanism of X-ray generation via high-energy electrons interacting with tungsten atoms in the solid target.

  14. Plasma-Based Studies on 4th Generation Light Sources

    SciTech Connect

    Lee, R W; Baldis, H A; Cauble, R C; Landen, O L; Wark, J S; Ng, A; Rose, S J; Lewis, C; Riley, D; Gauthier, J-C; Audebert, P

    2000-11-28

    The construction of a short pulse tunable x-ray laser source will be a watershed for plasma-based and warm dense matter research. The areas we will discuss below can be separated broadly into warn dense matter (WDM) research, laser probing of near solid density plasmas, and laser-plasma spectroscopy of ions in plasmas. The area of WDM refers to that part of the density-temperature phase space where the standard theories of condensed matter physics and/or plasma statistical physics are invalid. Warm dense matter, therefore, defines a region between solids and plasmas, a regime that is found in planetary interiors, cool dense stars, and in every plasma device where one starts from a solid, e.g., laser-solid matter produced plasma as well as all inertial fusion schemes. The study of dense plasmas has been severely hampered by the fact that laser-based methods have been unavailable. The single most useful diagnostic of local plasma conditions, e.g., the temperature (T{sub e}), the density (n{sub e}), and the ionization (Z), has been Thomson scattering. However, due to the fact that visible light will not propagate at electron densities, n{sub e}, {ge} 10{sup 22} cm{sup -3} implies dense plasmas can not be probed. The 4th generation sources, LCLS and Tesla will remove these restrictions. Laser-based plasma spectroscopic techniques have been used with great success to determine the line shapes of atomic transitions in plasmas, study the population kinetics of atomic systems embedded in plasmas, and look at redistribution of radiation. However. the possibilities end for plasmas with n{sub e} {ge} 10{sup 22} since light propagation through the medium is severely altered by the plasma. The entire field of high Z plasma kinetics from laser produced plasma will then be available to study with the tunable source.

  15. Next-Generation X-Ray Astronomy

    NASA Technical Reports Server (NTRS)

    White, Nicholas E.

    2011-01-01

    The future timing capabilities in X-ray astronomy will be reviewed. This will include reviewing the missions in implementation: Astro-H, GEMS, SRG, and ASTROSAT; those under study: currently ATHENA and LOFT; and new technologies that may enable future missions e.g. Lobster eye optics. These missions and technologies will bring exciting new capabilities across the entire time spectrum from micro-seconds to years that e.g. will allow us to probe close to the event horizon of black holes and constrain the equation of state of neutron stars.

  16. Laser Electron Generator of the X-Ray Radiation

    NASA Astrophysics Data System (ADS)

    Artyukov, I. A.; Bessonov, E. G.; Vinogradov, A. V.; Gorbunkov, M. V.; Maslova, Yu. Ya.; Popov, N. L.; Postnov, A. A.; Uspenski, Yu. A.; Feshchenko, R. M.; Shabalin, Yu. V.; Slovokhotov, Yu. L.; Zubavichus, Ya. V.; Ishanov, B. S.; Poseryaev, A. V.; Shvedunov, V. I.; Kostrukov, P. V.; Tunkin, V. G.

    The possibility of the creation and the application prospects of the laser-electron X-ray generator based on the Thompson scattering of the laser radiation on a bunch of relativistic electrons are considered. Such a generator fills the existing gap between X-ray tubes and synchrotron sources, which is several orders of magnitude in terms of the brightness, average intensity, size and also in the construction and exploitation costs. The layout of beam-lines and experimental stations intended for the applications of the X-ray laser-electron generator to the investigation of the elemental composition and material structure and biological objects is discussed.

  17. Methods of Attosecond X-Ray Pulse Generation

    SciTech Connect

    Zholents, Alexander

    2005-05-08

    We review several proposals for generation of solitary attosecond pulses using two types of free electron lasers which are envisioned as future light sources for studies of ultra-fast dynamics using soft and hard x-rays.

  18. Pulsed x-ray generator for commercial gas lasers

    NASA Astrophysics Data System (ADS)

    Bollanti, S.; Bonfigli, F.; Di Lazzaro, P.; Flora, F.; Giordano, G.; Letardi, T.; Murra, D.; Schina, G.; Zheng, C. E.

    2001-10-01

    We have designed and tested a 1-m-long x-ray diode based on innovative plasma cathodes, which exploit commercial spark plugs as electron emitters. Based on the results of a numerical study, we optimized both diode geometry (e.g., the angle between anode and cathode surfaces, the thickness of the Al window) and electrical circuitry (e.g., the capacitance in series to each spark plug, the peak voltage of the anode) of our x-ray generator. The overall result is a simple and efficient circuitry, giving a total diode current in excess of 2.1 kA with a breakdown voltage of 70 kV, which generates a 50 ns rise-time x-ray pulse with a spatially averaged dosage of up to 6×10-4 Gy when using a Pb-wrapped anode. The double-diode x-ray generator was operated for 1.5×106 shots at a repetition rate of up to 30 Hz, and the lifetime test was interrupted without any fault. During the lifetime test, it was not necessary to adjust any working parameter. At the end of the lifetime test, the x-ray emission uniformity was better than 80% along the longitudinal axis. This x-ray generator has a lifetime, reliability, and cost fitting the requirements of industrial users. Among the broad range of potential applications, this x-ray generator is particularly suitable to ionize discharge pumped gas lasers, like TEA CO2 and excimer lasers, including those operated by x-ray triggered discharges.

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

    SciTech Connect

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

    2006-04-07

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

  20. A virtual experiment on pyroelectric X-ray generator

    NASA Astrophysics Data System (ADS)

    Nasseri, Mohammad Mehdi

    2015-09-01

    The production of pyroelectric type X-ray generators has a long term background. In case of using X-ray generators containing two pyroelectric crystals, some parameters have not been practically measured yet. This article aims to calculate such parameters by means of Geant4 Mont Carlo codes. The obtained edge energy of initial electrons was 3 keV at a constant pressure of 1mTorr and electric field of 250 kV/cm. The amplification coefficient production of electrons was increased reaching to a constant value of 2.7. The observed mean energy of produced gas ions was approximately 39 eV, equivalent to 5.7% of the emitted electrons. The efficiency of the generated X-ray was about 63% and did not show a considerable change as the energy of initial electrons increased.

  1. Lightweight Target Generates Bright, Energetic X-Rays

    SciTech Connect

    Hazi, A

    2006-01-25

    Radiography with x rays is a long-established method to see inside objects, from human limbs to weapon parts. Livermore scientists have a continuing need for powerful x rays for such applications as backlighting, or illuminating, inertial confinement fusion (ICF) experiments and imaging still or exploding materials for the nation's Stockpile Stewardship Program. X-radiography is one of the prime diagnostics for ICF experiments because it captures the fine detail needed to determine what happens to nearly microscopic targets when they are compressed by laser light. For example, Livermore scientists participating in the National Ignition Facility's (NIF's) 18-month-long Early Light experimental campaign, which ended in 2004, used x rays to examine hydrodynamic instabilities in jets of plasma. In these experiments, one laser beam irradiated a solid target of titanium, causing it to form a high-temperature plasma that generated x rays of about 4.65 kiloelectronvolts (keV). These x rays backlit a jet of plasma formed when two other laser beams hit a plastic ablator and sent a shock to an aluminum washer. Livermore physicist Kevin Fournier of the Physics and Advanced Technologies Directorate leads a team that is working to increase the efficiency of converting laser energy into x rays so the resulting images provide more information about the object being illuminated. The main characteristics of x-ray sources are energy and brightness. ''As experimental targets get larger and as compression of the targets increases, the backlighter sources must be brighter and more energetic'', says Fournier. The more energetic the x rays, the further they penetrate an object. The brighter the source--that is, the more photons it has--the clearer the image. historically, researchers have used solid targets such as thin metal foils to generate x rays. however, when photon energies are greater than a few kiloelectronvolts, the conversion efficiency of solid targets is only a fraction of 1

  2. Ignitron-driven soft flash x-ray generator

    NASA Astrophysics Data System (ADS)

    Sagae, Michiaki; Sato, Eiichi; Ichimaru, Toshio; Obara, Haruo; Sakamaki, Kimio; Takayama, Kazuyoshi; Tamakawa, Yoshiharu

    1997-12-01

    The fundamental study on a soft flash x-ray generator utilizing an ignitron is described. This generator consists of the following essential components: a high-voltage power supply, a high-voltage pulser having an ignitron, an oil diffusion pump, and a flash x-ray tube. The x-ray tube employs a molybdenum anode rod, a pipe-shaped carbon cathode, a polymethylmeth acrylate tube body, and a polyethylene terephthalate x-ray window. The space between the anode and the cathode electrodes (ac space) can be controlled by rotating the anode rod. The high-voltage condenser in the pulser is charged from 40 to 60 kV by the power supply, and the electric charges in the condenser are discharged to the tube by the ignitron through a 2.0 m coaxial cable. Because the maximum anode voltage of the ignitron is 50 kV, a free-air gap switch is employed in order to increase the high-voltage durability. In the present work, the anode electrode is connected to the ground, and the negative high-voltage output is applied to the cathode electrode. The flash x-rays are then produced. The peak cathode voltage and tube current had values of minus 56 kV and 11.5 kA, respectively, with a charging voltage of 60 kV and an ac space of 6.0 mm, and the pulse widths were less than 300 ns.

  3. pyXSIM: Synthetic X-ray observations generator

    NASA Astrophysics Data System (ADS)

    ZuHone, John A.; Hallman, Eric. J.

    2016-08-01

    pyXSIM simulates X-ray observations from astrophysical sources. X-rays probe the high-energy universe, from hot galaxy clusters to compact objects such as neutron stars and black holes and many interesting sources in between. pyXSIM generates synthetic X-ray observations of these sources from a wide variety of models, whether from grid-based simulation codes such as FLASH (ascl:1010.082), Enzo (ascl:1010.072), and Athena (ascl:1010.014), to particle-based codes such as Gadget (ascl:0003.001) and AREPO, and even from datasets that have been created “by hand”, such as from NumPy arrays. pyXSIM can also manipulate the synthetic observations it produces in various ways and export the simulated X-ray events to other software packages to simulate the end products of specific X-ray observatories. pyXSIM is an implementation of the PHOX (ascl:1112.004) algorithm and was initially the photon_simulator analysis module in yt (ascl:1011.022); it is dependent on yt.

  4. Numerical simulations of x-ray generation in miltisectional FELs

    SciTech Connect

    Pitatelev, M.M.

    1995-12-31

    The process of x-ray generation in milticomponent FELs with alternate undulator and dispersion sections is investigate. The coptuter simulation was fulfilled for the ultrarelativistic electron beams. It was shown that the use of much number of dispersion sections allows to increase the gain considerably and to use more short magnetic systems.

  5. Design, analysis and testing of x-ray tube for next generation x-ray machines

    NASA Astrophysics Data System (ADS)

    Sanganal, Santoshakumar; Rao Ratnala, Srinivas; Shivakumar Gouda, P. S.

    2016-09-01

    A conceptual design of x-ray metal tube frame assembly is done to establish the technical feasibility and characterize the performance of a base design of x-ray metal tube frame assembly to meet the experimental critical to qualities (CTQ's) of x-ray tube at 72 kW for 20 seconds. Experimental test configuration with linear variable differential transformers (LVDT's) & thermo-couples is set to study the thermal prediction of x-ray tube with model results. Graphs of temperature versus time and deflection versus time shows curve shape magnitudes within 5% and 1%. A thermal - structural analysis is considered in analyzing the thermal - structural behavior in x-ray metal tube by considering worst protocol as 3.2 kW in steady state condition and 14.4 kW in transient state condition for 30 seconds. This analysis is done by doing a conceptual design of x-ray metal tube frame assembly with major modifications in frame and electron collector based on thermal - structural results. 3D modelling of x-ray metal tube frame assembly is done in Creo parametric 2.0 CAD software and analysis is done in ANSYS 16.1 simulation software. FEA results of conceptual design are in good agreement with CTQ's results of x-ray tube at 72 kW for 20 seconds.

  6. A laboratory model of post-Newtonian gravity with high power lasers and 4th generation light sources

    NASA Astrophysics Data System (ADS)

    Gregori, G.; Levy, M. C.; Wadud, M. A.; Crowley, B. J. B.; Bingham, R.

    2016-04-01

    Using the post-Newtonian formalism of gravity, we attempt to calculate the x-ray Thomson scattering cross section of electrons that are accelerated in the field of a high intensity optical laser. We show that our results are consistent with previous calculations, suggesting that the combination of high power laser and 4th generation light sources may become a powerful platform to test models exploring high order corrections to the Newtonian gravity.

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

    SciTech Connect

    Pivovaroff, M; Soufli, R

    2007-03-01

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

  8. ELECTRON INJECTORS FOR NEXT GENERATION X-RAY SOURCES.

    SciTech Connect

    BLUEM,H.; BEN-ZVI,I.; SRINIVASAN-RAO,T.; ET AL.

    2004-08-02

    Next generation x-ray sources require very high-brightness electron beams that are typically at or beyond the present state-of-the-art, and thus place stringent and demanding requirements upon the electron injector parameters. No one electron source concept is suitable for all the diverse applications envisaged, which have operating characteristics ranging from high-average-current, quasi-CW, to high-peak-current, single-pulse electron beams. Advanced Energy Systems, in collaboration with various partners, is developing several electron injector concepts for these x-ray source applications. The performance and design characteristics of five specific RF injectors, spanning ''L'' to ''X''-band, normal-conducting to superconducting, and low repetition rate to CW, which are presently in various stages of design, construction or testing, is described. We also discuss the status and schedule of each with respect to testing.

  9. X-ray Generation in Strongly Nonlinear Plasma Waves

    NASA Astrophysics Data System (ADS)

    Kiselev, S.; Pukhov, A.; Kostyukov, I.

    2004-09-01

    We show that a laser wake field in the “bubble” regime [

    A. Pukhov and J. Meyer-ter-Vehn Appl. Phys. BAPBOEM0946-2171 74, 355 (2002)10.1007/s003400200795
    ], works as a compact high-brightness source of x-rays. The self-trapped relativistic electrons make betatron oscillations in the transverse fields of the bubble and emit a bright broadband x-ray radiation with a maximum about 50 keV. The emission is confined to a small angle of about 0.1 rad. In addition, we make simulations of x-ray generation by an external 28.5 GeV electron bunch injected into the bubble. γ quanta with up to GeV energies are observed in the simulation in good agreement with analytical results. The energy conversion is efficient, leading to a significant stopping of the electron bunch over 5 mm interaction distance.

  10. Generation of Coherent X-Ray Radiation Through Modulation Compression

    SciTech Connect

    Qiang, Ji; Wu, Juhao

    2010-12-14

    In this letter, we propose a scheme to generate tunable coherent X-ray radiation for future light source applications. This scheme uses an energy chirped electron beam, a laser modulators, a laser chirper and two bunch compressors to generate a prebunched kilo-Ampere current electron beam from a few tens Ampere electron beam out of a linac. The initial modulation energy wavelength can be compressed by a factor of 1 + h{sub b}R{sub 56}{sup a} phase space, where h{sub b} is the energy bunch length chirp introduced by the laser chirper, R{sub 56}{sup a} is the momentum compaction factor of the first bunch compressor. As an illustration, we present an example to generate more than 400 MW, 170 atto-seconds pulse, 1 nm coherent X-ray radiation using a 60 Ampere electron beam out. of the linac and 200 nm laser seed. Both the final wavelength and the radiation pulse length in the proposed scheme are tunable by adjusting the compression factor and the laser parameters.

  11. Generation of Coherent X-Ray Radiation through Modulation Compression

    SciTech Connect

    Qiang, Ji; Wu, Juhao; /SLAC

    2012-06-12

    In this paper, we propose a scheme to generate tunable coherent X-ray radiation for future light source applications. This scheme uses an energy chirped electron beam, a laser modulator, a laser chirper and two bunch compressors to generate a prebunched kilo-Ampere current electron beam from a few tens Ampere electron beam out of a linac. The initial modulation energy wavelength can be compressed by a factor of 1 + h{sub b}R{sub 56}{sup a} in phase space, where h{sub b} is the energy bunch length chirp introduced by the laser chirper, R{sub 56}{sup a} is the momentum compaction factor of the first bunch compressor. As an illustration, we present an example to generate more than 400 MW, 170 attoseconds pulse, 1 nm coherent X-ray radiation using a 60 A electron beam out of the linac and 200 nm laser seed. Both the final wavelength and the radiation pulse length in the proposed scheme are tunable by adjusting the compression factor and the laser parameters.

  12. GENERATION OF SUBPICOSECOND X-RAY PULSES IN STORAGE RINGS

    SciTech Connect

    Zholents, Alexander A.

    2007-06-19

    Supicosecond x-ray pulses are routinely produced at ALS,BESSY and SLS with slicing technique and used in pump-probe experimentswith controlled delay between laser pump pulses and x-ray probe pulses.New development aiming for a production of a subpicosecond x-ray pulsesusing rf orbit deflection technique is under way at APS. Both techniqueswill be reviewed here.

  13. Tuning the Performance of Organic Spintronic Devices Using X-Ray Generated Traps

    DTIC Science & Technology

    2012-08-16

    REPORT Tuning the Performance of Organic Spintronic Devices Using X-Ray Generated Traps 14. ABSTRACT 16. SECURITY CLASSIFICATION OF: X rays produced...during electron-beam deposition of metallic electrodes drastically change the performance of organic spintronic devices. The x rays generate traps with...Form 298 (Rev 8/98) Prescribed by ANSI Std. Z39.18 - Tuning the Performance of Organic Spintronic Devices Using X-Ray Generated Traps Report Title

  14. Picosecond x-ray diagnostics for third and fourth generation synchrotron sources

    SciTech Connect

    DeCamp, Matthew

    2016-03-30

    In the DOE-EPSCoR State/National Laboratory partnership grant ``Picosecond x-ray diagnostics for third and fourth generation synchrotron sources'' Dr. DeCamp set forth a partnership between the University of Delaware and Argonne National Laboratory. This proposal aimed to design and implement a series of experiments utilizing, or improving upon, existing time-domain hard x-ray spectroscopies at a third generation synchrotron source. Specifically, the PI put forth three experimental projects to be explored in the grant cycle: 1) implementing a picosecond ``x-ray Bragg switch'' using a laser excited nano-structured metallic film, 2) designing a robust x-ray optical delay stage for x-ray pump-probe studies at a hard x-ray synchrotron source, and 3) building/installing a laser based x-ray source at the Advanced Photon Source for two-color x-ray pump-probe studies.

  15. Compact high current generator for x-ray radiography

    NASA Astrophysics Data System (ADS)

    Kharlov, A. V.; Kovalchuk, B. M.; Zorin, V. B.

    2006-12-01

    We report here a design of the portable high current generator, which can be used for a row of experiments and applications, including, but not limited to, X pinch, plasma focus, vacuum spark, etc. The X generator consists of the capacitor bank, multigap spark switch, load chamber, and built-in high voltage triggering generator. The capacitor bank consists of 12 General Atomics 35404 type capacitors (20nF, 25nH, 0.2Ω, 100kV). It stores ˜0.8kJ at 80kV charging voltage. Each three capacitors are commuted to a load by the multigap spark switch, which is able to commute by eight parallel channels. Switches operate in ambient air at atmospheric pressure. At 76kV charging voltage the generator provides ˜260kA with 120ns rise time and 5nH inductive load and ˜220kA with 145ns rise time and 10nH. Delay of output pulse relative to high voltage triggering pulse is ˜65ns with 5ns jitter. The dimensions of the generator are 1240×1240×225mm3 and the weight is ˜250kg, and only one high voltage power supply is required as additional equipment for the generator. The generator with a pumping system is placed on area about 0.5m2. Operation and handling are very simple, because no oil nor purified gases are required for the generator. The X generator has been successfully employed for experiments on the Ni X pinch load. X-ray pulse duration (full width at half maximum above 1keV) was about 5ns. Radiation yield Wr⩾500mJ was observed in the 1.2-1.5KeV range and Wr⩾20mJ in the 3-5keV energy range, which is comparable to results, obtained on the nanosecond accelerators. Clearly resolved images of 6μm wire indicate micron level size of hot spot. These results demonstrate possibility of this generator for application for x-ray backlighting.

  16. X rays generated in the interaction of subpicosecond laser pulses with solid targets

    SciTech Connect

    Kyrala, G.A.; Wahlin, E.K.; Fulton, R.D.; Schappert, G.T.; Jones, L.A.; Taylor, A.J.; Casperson, D.E.; Cobble, J.A.

    1991-01-01

    We are investigating the generation of short pulse short wavelength x-rays for pumping inner-shell x-ray lasers by photo-ionization. In contrast with previous proposals, we are looking at the use of a single line as an efficient means of pumping these lasers. As a first step we are optimizing the flashlamp x-ray conversion efficiency and characterizing the x-ray pulse length. 18 refs., 5 figs., 2 tabs.

  17. Active x-ray optics for Generation-X, the next high resolution x-ray observatory

    NASA Astrophysics Data System (ADS)

    Elvis, Martin; Brissenden, R. J.; Fabbiano, G.; Schwartz, D. A.; Reid, P.; Podgorski, W.; Eisenhower, M.; Juda, M.; Phillips, J.; Cohen, L.; Wolk, S.

    2006-06-01

    X-rays provide one of the few bands through which we can study the epoch of reionization, when the first galaxies, black holes and stars were born. To reach the sensitivity required to image these first discrete objects in the universe needs a major advance in X-ray optics. Generation-X (Gen-X) is currently the only X-ray astronomy mission concept that addresses this goal. Gen-X aims to improve substantially on the Chandra angular resolution and to do so with substantially larger effective area. These two goals can only be met if a mirror technology can be developed that yields high angular resolution at much lower mass/unit area than the Chandra optics, matching that of Constellation-X (Con-X). We describe an approach to this goal based on active X-ray optics that correct the mid-frequency departures from an ideal Wolter optic on-orbit. We concentrate on the problems of sensing figure errors, calculating the corrections required, and applying those corrections. The time needed to make this in-flight calibration is reasonable. A laboratory version of these optics has already been developed by others and is successfully operating at synchrotron light sources. With only a moderate investment in these optics the goals of Gen-X resolution can be realized.

  18. Characterization of X-ray generator beam profiles.

    SciTech Connect

    Mitchell, Dean J; Harding, Lee T.; Thoreson, Gregory G.; Theisen, Lisa Anne; Parmeter, John Ethan; Thompson, Kyle Richard

    2013-07-01

    T to compute the radiography properties of various materials, the flux profiles of X-ray sources must be characterized. This report describes the characterization of X-ray beam profiles from a Kimtron industrial 450 kVp radiography system with a Comet MXC-45 HP/11 bipolar oil-cooled X-ray tube. The empirical method described here uses a detector response function to derive photon flux profiles based on data collected with a small cadmium telluride detector. The flux profiles are then reduced to a simple parametric form that enables computation of beam profiles for arbitrary accelerator energies.

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

    PubMed

    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.

  20. 21 CFR 892.1700 - Diagnostic x-ray high voltage generator.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Diagnostic x-ray high voltage generator. 892.1700 Section 892.1700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... generator. (a) Identification. A diagnostic x-ray high voltage generator is a device that is intended...

  1. 21 CFR 892.1700 - Diagnostic x-ray high voltage generator.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Diagnostic x-ray high voltage generator. 892.1700 Section 892.1700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... generator. (a) Identification. A diagnostic x-ray high voltage generator is a device that is intended...

  2. 21 CFR 892.1700 - Diagnostic x-ray high voltage generator.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Diagnostic x-ray high voltage generator. 892.1700 Section 892.1700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... generator. (a) Identification. A diagnostic x-ray high voltage generator is a device that is intended...

  3. 21 CFR 892.1700 - Diagnostic x-ray high voltage generator.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Diagnostic x-ray high voltage generator. 892.1700 Section 892.1700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... generator. (a) Identification. A diagnostic x-ray high voltage generator is a device that is intended...

  4. 21 CFR 892.1700 - Diagnostic x-ray high voltage generator.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Diagnostic x-ray high voltage generator. 892.1700 Section 892.1700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... generator. (a) Identification. A diagnostic x-ray high voltage generator is a device that is intended...

  5. Next generation x-ray all-sky monitor

    SciTech Connect

    Priedhorsky, W. C.; Peele, A. G.; Nugent, K. A.

    1997-01-10

    We set forth a conceptual design for x-ray all-sky monitor based on lobster-eye wide-field telescopes. This instrument, suitable for a small satellite, would monitor the flux of objects as faint as 2x10{sup -15} W/m{sup 2} (0.5-2.4 keV) on a daily basis with a signal-to-noise of 5. Sources would be located to 1-2 arc-minutes. Detailed simulations show that crosstalk from the cruciform lobster images would not significantly compromise performance. At this sensitivity limit, we could monitor not just x-ray binaries but fainter classes of x-ray sources. Hundreds of active galactic nuclei, coronal sources, and cataclysmic variables could be tracked on a daily basis. Large numbers of fast transients should be visible, including gamma-ray bursts and the soft x-ray breakout of nearby type II supernovae. Long-term x-ray measurements will advance our understanding of the geometries and perhaps masses of AGN, and coronal energy sources in stars.

  6. Comparison of Single Event Transients Generated by Short Pulsed X-Rays, Lasers and Heavy Ions

    SciTech Connect

    Cardoza, David; LaLumondiere, Stephen D.; Tockstein, Michael A.; Brewe, Dale L.; Wells, Nathan P.; Koga, Rokutaro; Gaab, K. M.; Lotshaw, William T.; Moss, Steven C.

    2014-12-01

    We report an experimental study of the transients generated by pulsed x-rays, heavy ions, and different laser wavelengths in a Si p-i-n photodiode. We compare the charge collected by all of the excitation methods to determine the equivalent LET for pulsed x-rays relative to heavy ions. Our comparisons show that pulsed x-rays from synchrotron sources can generate a large range of equivalent LET and generate transients similar to those excited by laser pulses and heavy ion strikes. We also look at how the pulse width of the transients changes for the different excitation methods. We show that the charge collected with pulsed x-rays is greater than expected as the x-ray photon energy increases. Combined with their capability of focusing to small spot sizes and of penetrating metallization, pulsed x-rays are a promising new tool for high resolution screening of SEE susceptibility

  7. Long life electrodes for large-area x-ray generators

    NASA Technical Reports Server (NTRS)

    Rothe, Dietmar E. (Inventor)

    1991-01-01

    This invention is directed to rugged, reliable, and long-life electrodes for use in large-area, high-current-density electron gun and x-ray generators which are employed as contamination-free preionizers for high-energy pulsed gas lasers. The electron source at the cathode is a corona plasma formed at the interface between a conductor, or semiconductor, and a high-permittivity dielectric. Detailed descriptions are provided of a reliable cold plasma cathode, as well as an efficient liquid-cooled electron beam target (anode) and x-ray generator which concentrates the x-ray flux in the direction of an x-ray window.

  8. Generation of apodized X-ray illumination and its application to scanning and diffraction microscopy.

    PubMed

    Khakurel, Krishna P; Kimura, Takashi; Nakamori, Hiroki; Goto, Takumi; Matsuyama, Satoshi; Sasaki, Tomoya; Takei, Masashi; Kohmura, Yoshiki; Ishikawa, Tetsuya; Yamauchi, Kazuto; Nishino, Yoshinori

    2017-01-01

    X-ray science has greatly benefited from the progress in X-ray optics. Advances in the design and the manufacturing techniques of X-ray optics are key to the success of various microscopic and spectroscopic techniques practiced today. Here the generation of apodized X-ray illumination using a two-stage deformable Kirkpatrick-Baez mirror system is presented. Such apodized illumination is marked by the suppression of the side-lobe intensities of the focused beam. Thus generated apodized illumination was employed to improve the image quality in scanning X-ray fluorescence microscopy. Imaging of a non-isolated object by coherent X-ray diffractive imaging with apodized illumination in a non-scanning mode is also presented.

  9. The AAPM/RSNA physics tutorial for residents. X-ray generators.

    PubMed

    Seibert, J A

    1997-01-01

    The x-ray generator delivers the electrical power to energize the x-ray tube and permits the selection of x-ray energy, x-ray quantity, and exposure time. Major internal components of the generator include transformers, diodes and rectifier circuits, filament and stator circuits, timer switches, and kilovolt and milliampere meters. Single-phase, three-phase, high-frequency, and constant potential generators produce different voltage waveforms (ripple) and x-ray beam spectra. Phototimer and automatic brightness control subsystems measure radiation exposure incident on the image receptor to give instantaneous feedback for optimal radiographic film densities and fluoroscopic image brightness, respectively. At the generator control console, the operator sets the tube voltage, tube current, exposure time, phototimer film density, spot film acquisition, and fluoroscopic parameters. Selection of generator power and options depends on the intended clinical use. X-ray tube focal spot size and power loading capability should be matched to the x-ray generator and clinical imaging requirements. Single and multiple exposure rating charts as well as anode and housing thermal characteristic charts indicate power input and dissipation rates specific to a generator and x-ray tube target and housing.

  10. X-ray generation by inverse Compton scattering at the superconducting RF test facility

    NASA Astrophysics Data System (ADS)

    Shimizu, Hirotaka; Akemoto, Mitsuo; Arai, Yasuo; Araki, Sakae; Aryshev, Alexander; Fukuda, Masafumi; Fukuda, Shigeki; Haba, Junji; Hara, Kazufumi; Hayano, Hitoshi; Higashi, Yasuo; Honda, Yosuke; Honma, Teruya; Kako, Eiji; Kojima, Yuji; Kondo, Yoshinari; Lekomtsev, Konstantin; Matsumoto, Toshihiro; Michizono, Shinichiro; Miyoshi, Toshinobu; Nakai, Hirotaka; Nakajima, Hiromitsu; Nakanishi, Kota; Noguchi, Shuichi; Okugi, Toshiyuki; Sato, Masato; Shevelev, Mikhail; Shishido, Toshio; Takenaka, Tateru; Tsuchiya, Kiyosumi; Urakawa, Junji; Watanabe, Ken; Yamaguchi, Seiya; Yamamoto, Akira; Yamamoto, Yasuchika; Sakaue, Kazuyuki; Hosoda, Seiichi; Iijima, Hokuto; Kuriki, Masao; Tanaka, Ryuta; Kuramoto, Ayaka; Omet, Mathieu; Takeda, Ayaki

    2015-02-01

    Quasi-monochromatic X-rays with high brightness have a broad range of applications in fields such as life sciences, bio-, medical applications, and microlithography. One method for generating such X-rays is via inverse Compton scattering (ICS). X-ray generation experiments using ICS were carried out at the superconducting RF test facility (STF) accelerator at KEK. A new beam line, newly developed four-mirror optical cavity system, and new X-ray detector system were prepared for experiments downstream section of the STF electron accelerator. Amplified pulsed photons were accumulated into a four-mirror optical cavity and collided with an incoming 40 MeV electron beam. The generated X-rays were detected using a microchannel plate (MCP) detector for X-ray yield measurements and a new silicon-on-insulator (SOI) detector system for energy measurements. The detected X-ray yield by the MCP detector was 1756.8±272.2 photons/(244 electron bunches). To extrapolate this result to 1 ms train length under 5 Hz operations, 4.60×105 photons/1%-bandwidth were obtained. The peak X-ray energy, which was confirmed by the SOI detector, was 29 keV, and this is consistent with ICS X-rays.

  11. Development of partially-coherent wavefront propagation simulation methods for 3rd and 4th generation synchrotron radiation sources

    NASA Astrophysics Data System (ADS)

    Chubar, Oleg; Berman, Lonny; Chu, Yong S.; Fluerasu, Andrei; Hulbert, Steve; Idir, Mourad; Kaznatcheev, Konstantine; Shapiro, David; Shen, Qun; Baltser, Jana

    2011-09-01

    Partially-coherent wavefront propagation calculations have proven to be feasible and very beneficial in the design of beamlines for 3rd and 4th generation Synchrotron Radiation (SR) sources. These types of calculations use the framework of classical electrodynamics for the description, on the same accuracy level, of the emission by relativistic electrons moving in magnetic fields of accelerators, and the propagation of the emitted radiation wavefronts through beamline optical elements. This enables accurate prediction of performance characteristics for beamlines exploiting high SR brightness and/or high spectral flux. Detailed analysis of radiation degree of coherence, offered by the partially-coherent wavefront propagation method, is of paramount importance for modern storage-ring based SR sources, which, thanks to extremely small sub-nanometer-level electron beam emittances, produce substantial portions of coherent flux in X-ray spectral range. We describe the general approach to partially-coherent SR wavefront propagation simulations and present examples of such simulations performed using "Synchrotron Radiation Workshop" (SRW) code for the parameters of hard X-ray undulator based beamlines at the National Synchrotron Light Source II (NSLS-II), Brookhaven National Laboratory. These examples illustrate general characteristics of partially-coherent undulator radiation beams in low-emittance SR sources, and demonstrate advantages of applying high-accuracy physical-optics simulations to the optimization and performance prediction of X-ray optical beamlines in these new sources.

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

    SciTech Connect

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

    1997-04-01

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

  13. X-Ray Measurements Of A Thermo Scientific P385 DD Neutron Generator

    NASA Astrophysics Data System (ADS)

    Wharton, C. J.; Seabury, E. H.; Chichester, D. L.; Caffrey, A. J.; Simpson, J.; Lemchak, M.

    2011-06-01

    Idaho National Laboratory is experimenting with electrical neutron generators, as potential replacements for californium-252 radioisotopic neutron sources in its PINS prompt gamma-ray neutron activation analysis (PGNAA) system for the identification of military chemical warfare agents and explosives. In addition to neutron output, we have recently measured the x-ray output of the Thermo Scientific P385 deuterium-deuterium neutron generator. X rays are a normal byproduct from neutron generators, but depending on their intensity and energy, x rays can interfere with gamma rays from the object under test, increase gamma-spectrometer dead time, and reduce PGNAA system throughput. The P385 x-ray energy spectrum was measured with a high-purity germanium (HPGe) detector, and a broad peak is evident at about 70 keV. To identify the source of the x rays within the neutron generator assembly, it was scanned by collimated scintillation detectors along its long axis. At the strongest x-ray emission points, the generator also was rotated 60° between measurements. The scans show the primary source of x-ray emission from the P385 neutron generator is an area 60 mm from the neutron production target, in the vicinity of the ion source. Rotation of the neutron generator did not significantly alter the x-ray count rate, and its x-ray emission appears to be axially symmetric. A thin lead shield, 3.2 mm (1/8 inch) thick, reduced the 70-keV generator x rays to negligible levels.

  14. X-Ray Measurements Of A Thermo Scientific P385 DD Neutron Generator

    SciTech Connect

    Wharton, C. J.; Seabury, E. H.; Chichester, D. L.; Caffrey, A. J.; Simpson, J.; Lemchak, M.

    2011-06-01

    Idaho National Laboratory is experimenting with electrical neutron generators, as potential replacements for californium-252 radioisotopic neutron sources in its PINS prompt gamma-ray neutron activation analysis (PGNAA) system for the identification of military chemical warfare agents and explosives. In addition to neutron output, we have recently measured the x-ray output of the Thermo Scientific P385 deuterium-deuterium neutron generator. X rays are a normal byproduct from neutron generators, but depending on their intensity and energy, x rays can interfere with gamma rays from the object under test, increase gamma-spectrometer dead time, and reduce PGNAA system throughput. The P385 x-ray energy spectrum was measured with a high-purity germanium (HPGe) detector, and a broad peak is evident at about 70 keV. To identify the source of the x rays within the neutron generator assembly, it was scanned by collimated scintillation detectors along its long axis. At the strongest x-ray emission points, the generator also was rotated 60 deg. between measurements. The scans show the primary source of x-ray emission from the P385 neutron generator is an area 60 mm from the neutron production target, in the vicinity of the ion source. Rotation of the neutron generator did not significantly alter the x-ray count rate, and its x-ray emission appears to be axially symmetric. A thin lead shield, 3.2 mm (1/8 inch) thick, reduced the 70-keV generator x rays to negligible levels.

  15. Characterization of γ and γ' phases in 2nd and 4th generation single crystal nickel-base superalloys

    NASA Astrophysics Data System (ADS)

    Zietara, Maciej; Neumeier, Steffen; Göken, Mathias; Czyrska-Filemonowicz, Aleksandra

    2017-01-01

    A Ni based single crystal superalloy from the 2nd generation, PWA 1484, and one from the 4th generation, PWA 1497, were comparatively studied by scanning electron microscopy, energy dispersive X-ray spectroscopy and nanoindentation technique in an atomic force microscope (NI-AFM) after high temperature creep deformation. During primary creep of both generations of superalloys, γ' precipitates start to coalesce and grow directionally. Further creep deformation leads to the topological inversion and coarsening of the rafted microstructure. The NI-AFM technique was used for measurements of the hardness of the γ and γ' phases in as-received and creep deformed samples in various conditions. The g matrix of the PWA 1497 superalloy is on average 0.8 GPa harder than that of PWA 1484 that can be explained by higher content of Re and Ru, since they partition predominantly to the matrix phase.

  16. Thermal management of next-generation contact-cooled synchrotron x-ray mirrors

    SciTech Connect

    Khounsary, A.

    1999-10-29

    In the past decade, several third-generation synchrotrons x-ray sources have been constructed and commissioned around the world. Many of the major problems in the development and design of the optical components capable of handling the extremely high heat loads of the generated x-ray beams have been resolved. It is expected, however, that in the next few years even more powerful x-ray beams will be produced at these facilities, for example, by increasing the particle beam current. In this paper, the design of a next generation of synchrotron x-ray mirrors is discussed. The author shows that the design of contact-cooled mirrors capable of handing x-ray beam heat fluxes in excess of 500 W/mm{sup 2} - or more than three times the present level - is well within reach, and the limiting factor is the thermal stress rather then thermally induced slope error.

  17. A small, battery-operated fluoroscopic system - Lixiscope with X-ray generator

    NASA Technical Reports Server (NTRS)

    Yin, L. I.; Trombka, J. I.; Ruitberg, A. P.; Seltzer, S. M.

    1983-01-01

    A small, battery-operated X-ray generator has been developed to be used as part of a small-format fluoroscopic system, the Lixiscope (Low Intensity X-ray Imaging Scope). The X-ray generator consists of a grounded rod-anode X-ray tube with a 0.2 mm focal spot and a specially designed, battery-operated, 0 to -80 kV high-voltge supply. Total power consumption is about 10 W. The fine focal spot, in conjunction with the continuously variable X-ray intensity and spectral distribution, helps to extend both the versatility and the performance of the Lixiscope toward a much wider range of terrestrial and spacecraft applications. The complete fluoroscopic system is described, and some examples of possible applications are shown.

  18. A hybrid X-ray imaging spectrometer for NeXT and the next generation X-ray satellite

    NASA Astrophysics Data System (ADS)

    Tsuru, T. G.; Tanimori, T.; Bamba, A.; Imanishi, K.; Koyama, K.; Kubo, H.; Matsumoto, H.; Miuchi, K.; Nagayoshi, M.; Orito, R.; Takada, A.; Takagi, S.; Tsujimoto, M.; Ueno, M.; Tsunemi, H.; Hayashida, K.; Miyata, E.

    2004-01-01

    We propose a new type of wide band X-ray imaging spectrometer as a focal plane detector of the super mirror onboard on future X-ray missions including post Astro-E2. This camera is realized by the hybrid of back illumination CCDs and a back supportless CCD for 0.05-10 keV band, and a Micro Pixel Gas Chamber detecting X-rays at 10-80 keV.

  19. Optics Requirements For The Generation-X X-Ray Telescope

    NASA Technical Reports Server (NTRS)

    O'Dell, S. .; Elsner, R. F.; Kolodziejczak, J. J.; Ramsey, B. D.; Weisskopf, M. C.; Zhang, W. W.; Content, D. A.; Petre, R.; Saha, T. T.; Reid, P. B.; Schwartz, D. A.; Brissenden, R. J.; Elvis, M.; Freeman, M.; Gaetz, T.; Gorenstein, P.; Jerius, D.; Juda, M.; Murray, S. S.; Podgorski, W. A.; Wolk, S. J.; Trolier-McKinstry, S.

    2008-01-01

    US, European, and Japanese space agencies each now operate successful X-ray missions -- NASA s Chandra, ESA s XMM-Newton, and JAXA s Suzaku observatories. Recently these agencies began a collaboration to develop the next major X-ray astrophysics facility -- the International X-ray Observatory (IXO) -- for launch around 2020. IXO will provide an order-of-magnitude increase in effective area, while maintaining good (but not sub-arcsecond) angular resolution. X-ray astronomy beyond IXO will require optics with even larger aperture areas and much better angular resolution. We are currently conducting a NASA strategic mission concept study to identify technology issues and to formulate a technology roadmap for a mission -- Generation-X (Gen-X) -- to provide these capabilities. Achieving large X-ray collecting areas in a space observatory requires extremely lightweight mirrors.

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

    NASA Technical Reports Server (NTRS)

    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.

  1. Accuracy evaluation of a Compton X-ray spectrometer with bremsstrahlung X-rays generated by a 6 MeV electron bunch

    SciTech Connect

    Kojima, Sadaoki Arikawa, Yasunobu; Zhang, Zhe; Ikenouchi, Takahito; Morace, Alessio; Nagai, Takahiro; Abe, Yuki; Sakata, Shouhei; Inoue, Hiroaki; Utsugi, Masaru; Nakai, Mitsuo; Nishimura, Hiroaki; Shiraga, Hiroyuki; Fujioka, Shinsuke; Azechi, Hiroshi; Nishimura, Yasuhiko; Togawa, Hiromi; Ozaki, Tetsuo; Kato, Ryukou

    2014-11-15

    A Compton-scattering-based X-ray spectrometer is developed to obtain the energy distribution of fast electrons produced by intense laser and matter interactions. Bremsstrahlung X-rays generated by fast electrons in a material are used to measure fast electrons’ energy distribution in matter. In the Compton X-ray spectrometer, X-rays are converted into recoil electrons by Compton scattering in a converter made from fused silica glass, and a magnet-based electron energy analyzer is used to measure the energy distribution of the electrons that recoil in the direction of the incident X-rays. The spectrum of the incident X-rays is reconstructed from the energy distribution of the recoil electrons. The accuracy of this spectrometer is evaluated using a quasi-monoenergetic 6 MeV electron bunch that emanates from a linear accelerator. An electron bunch is injected into a 1.5 mm thick tungsten plate to produce bremsstrahlung X-rays. The spectrum of these bremsstrahlung X-rays is obtained in the range from 1 to 9 MeV. The energy of the electrons in the bunch is estimated using a Monte Carlo simulation of particle-matter interactions. The result shows that the spectrometer's energy accuracy is ±0.5 MeV for 6.0 MeV electrons.

  2. Accuracy evaluation of a Compton X-ray spectrometer with bremsstrahlung X-rays generated by a 6 MeV electron bunch.

    PubMed

    Kojima, Sadaoki; Arikawa, Yasunobu; Nishimura, Yasuhiko; Togawa, Hiromi; Zhang, Zhe; Ikenouchi, Takahito; Ozaki, Tetsuo; Morace, Alessio; Nagai, Takahiro; Abe, Yuki; Sakata, Shouhei; Inoue, Hiroaki; Utsugi, Masaru; Nakai, Mitsuo; Nishimura, Hiroaki; Shiraga, Hiroyuki; Kato, Ryukou; Fujioka, Shinsuke; Azechi, Hiroshi

    2014-11-01

    A Compton-scattering-based X-ray spectrometer is developed to obtain the energy distribution of fast electrons produced by intense laser and matter interactions. Bremsstrahlung X-rays generated by fast electrons in a material are used to measure fast electrons' energy distribution in matter. In the Compton X-ray spectrometer, X-rays are converted into recoil electrons by Compton scattering in a converter made from fused silica glass, and a magnet-based electron energy analyzer is used to measure the energy distribution of the electrons that recoil in the direction of the incident X-rays. The spectrum of the incident X-rays is reconstructed from the energy distribution of the recoil electrons. The accuracy of this spectrometer is evaluated using a quasi-monoenergetic 6 MeV electron bunch that emanates from a linear accelerator. An electron bunch is injected into a 1.5 mm thick tungsten plate to produce bremsstrahlung X-rays. The spectrum of these bremsstrahlung X-rays is obtained in the range from 1 to 9 MeV. The energy of the electrons in the bunch is estimated using a Monte Carlo simulation of particle-matter interactions. The result shows that the spectrometer's energy accuracy is ±0.5 MeV for 6.0 MeV electrons.

  3. Miniaturized X-ray Generation by Pyroelectric Effect using Short Pulse Laser

    DTIC Science & Technology

    2011-11-30

    1 Report of AOARD Program CONTRACT NO: FA23861014160 Miniaturized X-ray Generation by Pyroelectric Effect using Short Pulse Laser...induced currents by short- pulse high-power laser irradiation II-1: Experiments and results II-2: Theoretical calculations ~Analysis of currents...effect using short pulse laser aiming at miniaturized X-ray generator 5a. CONTRACT NUMBER FA23861014160 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6

  4. The 4th Generation Light Source at Jefferson Lab

    SciTech Connect

    Stephen Benson; George Biallas; James Boyce; Donald Bullard; James Coleman; David Douglas; H. Dylla; Richard Evans; Pavel Evtushenko; Albert Grippo; Christopher Gould; Joseph Gubeli; David Hardy; Carlos Hernandez-Garcia; Kevin Jordan; John Klopf; Steven Moore; George Neil; Thomas Powers; Joseph Preble; Daniel Sexton; Michelle D. Shinn; Christopher Tennant; Richard Walker; Shukui Zhang; Gwyn Williams

    2007-04-25

    A number of "Grand Challenges" in Science have recently been identified in reports from The National Academy of Sciences, and the U.S. Dept. of Energy, Basic Energy Sciences. Many of these require a new generation of linac-based light source to study dynamical and non-linear phenomena in nanoscale samples. In this paper we present a summary of the properties of such light sources, comparing them with existing sources, and then describing in more detail a specific source at Jefferson Lab. Importantly, the JLab light source has developed some novel technology which is a critical enabler for other new light sources.

  5. Generation of flash x-rays using a mercury-anode radiation tube

    NASA Astrophysics Data System (ADS)

    Oizumi, Teiji; Sato, Eiichi; Sagae, Michiaki; Hayasi, Yasuomi; Tamakawa, Yoshiharu; Yanagisawa, Toru

    1993-02-01

    The constructions and the radiographic characteristics of a flash x-ray generator having a liquid-anode radiation tube are described. This generator consisted of the following essential components: a high-voltage power supply, a combined ceramic condenser of 10.7 nF, an oil- diffusion pump, an oil circulator, a trigger device, and a flash x-ray tube. The x-ray tube was of a triode and was composed of the following major devices: a mercury anode, a rod-shaped graphite cathode, a trigger electrode made from a copper wire, an x-ray window made from a polyethyleneterephthalate film, and a glass tube body. The ceramic condenser was charged from 40 to 60 kV by a power supply, and the electric charges in the condenser were discharged to the x-ray tube after the triggering. The maximum tube voltage was equivalent to the initial charged voltage of the condenser, and the tube current was less than 0.7 kA. The pulse widths of the flash x rays had values of about 1 microsecond(s) , and the time-integrated x-ray intensity was about 2.4 (mu) C/kg at 0.26 m per pulse with a charged voltage of 60 kV.

  6. Wire array z-pinch insights for high x-ray power generation

    SciTech Connect

    Sanford, T.W.L.; Mock, R.C.; Nash, T.J.

    1998-08-01

    The discovery that the use of very large numbers of wires enables high x-ray power to be generated from wire-array z-pinches represents a breakthrough in load design for large pulsed power generators, and has permitted high temperatures to be generated in radiation cavities on Saturn. In this paper, changes in x-ray emission characteristics as a function of wire number, array mass, and load radius, for 20-mm-long aluminum arrays on Saturn that led to these breakthrough hohlraum results, are discussed and compared with a few related emission characteristics of high-wire-number aluminum and tungsten arrays on Z. X=ray measurement comparisons with analytic models and 2-D radiation-magnetohydrodynamic (RMHC) code simulations in the x-y and r-z planes provide confidence in the ability of the models and codes to predict future x-ray performance with very-large-number wire arrays.

  7. Wire array z-pinch insights for high x-ray power generation

    SciTech Connect

    Sanford, T.W.L.; Mock, R.C.; Marder, B.M.

    1997-12-31

    The discovery that the use of very large numbers of wires enables high x-ray power to be generated from wire-array z-pinches represents a breakthrough in load design for large pulsed power generators, and has permitted high temperatures to be generated in radiation cavities on Saturn and Z. In this paper, changes in x-ray emission characteristics as a function of wire number, array mass, and load radius, for 20-mm-long aluminum arrays on Saturn that led to these breakthrough hohlraum results, are discussed and compared with a few related emission characteristics of high-wire-number aluminum and tungsten arrays on Z. X-ray measurement comparisons with analytic models and 2-D radiation-magnetohydrodynamic (RMHC) code simulations in the x-y and r-z planes provide confidence in the ability of the models and codes to predict future x-ray performance with very-large-number wire arrays.

  8. Titanium dioxide nanofiber-cotton targets for efficient multi-keV x-ray generation

    SciTech Connect

    Tanabe, Minoru; Nishimura, Hiroaki; Fujioka, Shinsuke; Nagai, Keiji; Yamamoto, Norimasa; Mima, Kunioki; Gu, Zhong-Ze; Pan, Chao; Girard, Frederic; Primout, Michel; Villette, Bruno; Brebion, Didier; Fournier, Kevin B.; Fujishima, Akira

    2008-08-04

    Multi-keV x-ray generation from low-density (27{+-}7 mg/cm{sup 3}) nanofiber-cotton targets composed of titanium dioxide has been investigated. The cotton targets were heated volumetrically and supersonically to a peak electron temperature of 2.3 keV, which is optimal to yield Ti K-shell x rays. Considerable enhancement of conversion efficiency [(3.7{+-}0.5)%] from incident laser energy into Ti K-shell x rays (4-6 keV band) was attained in comparison with that [(1.4{+-}0.9)%] for a planar Ti-foil target.

  9. Ultrafast Material Science Probed Using Coherent X-ray Pulses from High-Harmonic Generation

    NASA Astrophysics Data System (ADS)

    Mathias, Stefan; Kapteyn, Henry C.; Murnane, Margaret M.

    X-rays represent one of the most powerful tools for understanding materials at the nanoscale, uncovering important information related to magnetism, photochemistry, materials, biology, nanoscience and many other areas of science and technology. The recent availability of ultrashort x-ray pulses paves the way for a completely new generation of experiments that can capture the coupled dynamics of elementary excitations in materials. Ultrashort x-ray pulses can access the fundamental interactions between charge, lattice, orbital, and spin dynamics in real time, which eventually determine the intrinsic physical limits at which, for example, a phase-transition in a correlated-electron material occurs, the magnetic state of a material can be switched, or a chemical reaction on a surface evolves. The goal of this chapter is to review recent breakthroughs in using ultrashort x-ray pulses from high-harmonic generation for the study of ultrafast material science.

  10. Coherent soft x-ray generation in the water window with quasi-phase matching.

    PubMed

    Gibson, Emily A; Paul, Ariel; Wagner, Nick; Tobey, Ra'anan; Gaudiosi, David; Backus, Sterling; Christov, Ivan P; Aquila, Andy; Gullikson, Eric M; Attwood, David T; Murnane, Margaret M; Kapteyn, Henry C

    2003-10-03

    We demonstrate enhanced generation of coherent light in the "water window" region of the soft x-ray spectrum at 4.4 nanometers, using quasi-phase-matched frequency conversion of ultrafast laser pulses. By periodically modulating the diameter of a gas-filled hollow waveguide, the phase mismatch normally present between the laser light and the generated soft x-ray light can be partially compensated. This makes it possible to use neon gas as the nonlinear medium to coherently convert light up to the water window, illustrating that techniques of nonlinear optics can be applied effectively in the soft x-ray region of the spectrum. These results advance the prospects for compact coherent soft x-ray sources for applications in biomicroscopy and in chemical spectroscopy.

  11. Generation Mechanisms UV and X-ray Emissions During SL9 Impact

    NASA Technical Reports Server (NTRS)

    Waite, J. Hunter, Jr.

    1997-01-01

    The purpose of this grant was to study the ultraviolet and X-ray emissions associated with the impact of comet Shoemaker-Levy 9 with Jupiter. The University of Michigan task was primarily focused on theoretical calculations. The NAGW-4788 subtask was to be largely devoted to determining the constraints placed by the X-ray observations on the physical mechanisms responsible for the generation of the X-rays. Author summarized below the ROSAT observations and suggest a physical mechanism that can plausibly account for the observed emissions. It is hoped that the full set of activities can be completed at a later date. Further analysis of the ROSAT data acquired at the time of the impact was necessary to define the observational constraints on the magnetospheric-ionospheric processes involved in the excitation of the X-ray emissions associated with the fragment impacts. This analysis centered around improvements in the pointing accuracy and improvements in the timing information. Additional pointing information was made possible by the identification of the optical counterparts to the X-ray sources in the ROSAT field-of-view. Due to the large number of worldwide observers of the impacts, a serendipitous visible plate image from an observer in Venezuela provided a very accurate location of the present position of the X-ray source, virtually eliminating pointing errors in the data. Once refined, the pointing indicated that the two observed X-ray brightenings that were highly correlated in time with the K and P2 events were brightenings of the X-ray aurora (as identified in images prior to the impact).Appendix A "ROSAT observations of X-ray emissions from Jupiter during the impact of comet Shoemaker-Levy 9' also included.

  12. Gas flow and generation of x ray emission in WR+OB binaries

    NASA Technical Reports Server (NTRS)

    Usov, V. V.

    1991-01-01

    The supersonic flow of the ionized gas in WR+OB binaries and X-ray generation are considered. X-ray emission is caused by gas heating up to temperatures of 10(exp 7) to 10(exp 8) K behind the front of shock waves. These are found in the collision of gas flowing out from the WR star with either the OB star's surface or the gas of the OB star's wind. The distribution of temperature and concentration behind the shock front are obtained. Using these distributions, the spectral power of bremsstrahlung X-ray emission of hot gas is calculated. Possible reasons that lead to a considerable difference between the observed parameters of X-ray emission of the WR binary of V 444 Cygni and the theoretically expected are discussed.

  13. Soft x-ray generation in gases with an ultrashort pulse laser

    SciTech Connect

    Ditmire, Todd Raymond

    1996-01-08

    An experimental investigation of soft x-ray production resulting from the interaction of intense near infra-red laser radiation with gases is presented in this thesis. Specifically, soft x-ray generation through high order harmonic generation or exploiting intense inverse bremsstrahlung heating is examined. Most of these studies are conducted with femtosecond, terawatt class Cr:LiSrAlF6 (LiSAF) laser, though results derived from studies with other laser systems are presented as well. The majority of this work is devoted to experimental investigations, however, theoretical and computational models are developed to interpret the data. These studies are motivated by the possibility of utilizing the physics of intense laser/matter interactions as a potential compact source of bright x-rays. Consequently, the thrust of many of the experiments conducted is aimed at characterizing the x-rays produced for possible use in applications. In general, the studies of this manuscript fall into three categories. First, a unique 130 fs, 8 TW laser that is based on chirped pulse amplification, is described, and its performance is evaluated. The generation of x-rays through high order harmonics is then discussed with emphasis on characterizing and optimizing harmonic generation. Finally, the generation of strong, incoherent x-ray radiation by the intense irradiation of large (>1,000 atom) clusters in gas jets, is explored. The physics of laser energy absorption by clusters illuminated with intensities of 1015 to 1017 W/cm2 is considered in detail. X-ray spectroscopy of the hot plasmas that result from the irradiation of the clusters is conducted, and energy transport and kinetics issues in these plasmas are discussed.

  14. Super-characteristic x-ray generator utilizing a pipe and rod target

    NASA Astrophysics Data System (ADS)

    Sato, Eiichi; Tanaka, Etsuro; Mori, Hidezo; Kawai, Toshiaki; Inoue, Takashi; Ogawa, Akira; Izumisawa, Mitsuru; Takahashi, Kiyomi; Sato, Shigehiro; Ichimaru, Toshio; Takayama, Kazuyoshi

    2006-08-01

    This generator consists of the following components: a constant high-voltage power supply, a filament power supply, a turbomolecular pump, and an x-ray tube. The x-ray tube is a demountable diode which is connected to the turbomolecular pump and consists of the following major devices: a tungsten hairpin cathode (filament), a focusing (Wehnelt) electrode, a polyethylene terephthalate x-ray window 0.25 mm in thickness, a stainless-steel tube body, a pipe target, and a rod target. The pipe and rod targets are useful for forming linear and cone beams, respectively. In the x-ray tube, the positive high voltage is applied to the anode (target) electrode, and the cathode is connected to the tube body (ground potential). In this experiment, the tube voltage applied was from12 to 20 kV, and the tube current was regulated to within 0.10 mA by the filament temperature. The exposure time is controlled in order to obtain optimum x-ray intensity. The electron beams from the cathode are converged to the target by the focusing electrode, and clean K-series characteristic x-rays are produced through the focusing electrode without using a filter. The x-ray intensities of the pipe and rod targets were 1.29 and 4.28 μGy/s at 1.0 m from the x-ray source with a tube voltage of 15 kV and a tube current of 0.10 mA, and quasi-monochromatic radiography was performed using a computed radiography system.

  15. Microwave Kinetic Inductance Detectors: Large Format X-ray Spectral Imagers for the Next Generation of X-ray Telescopes

    NASA Astrophysics Data System (ADS)

    Eckart, Megan E.; Mazin, B. A.; Bumble, B.; Golwala, S. R.; Zmuidzinas, J.; Day, P. K.; Harrison, F. A.

    2006-09-01

    Microwave Kinetic Inductance Detectors (MKIDs) have the potential to provide megapixel imagers with few eV spectral resolution for future X-ray missions such as Gen-X. MKIDs offer the advantage over many other cryogenic detector technologies that they can be easily multiplexed, so that arrays with many thousand pixels are readily achievable. In addition, the readout electronics can be operated at room temperature, a significant advantage for space applications. MKIDs exploit the dependence of surface impedance of a superconductorwith the quasiparticle density. Quasiparticles are created by absorption of X-rays, with number proportional to the X-ray energy. The impedance change may be sensitively measured using a thin-film resonant circuit. The practical application of MKIDs for photon detection requires a method of efficiently coupling the photon energy to the MKID. To apply the MKID scheme to X-ray detection we pattern tantalum strips with aluminum MKIDs attached at each end. An incident X-ray is absorbed in the Ta and creates millions of quasiparticle excitations, which diffuse to each end of the strip, finally entering the Al resonators where they are trapped and sensed. Simultaneous monitoring of the signal at both ends of the strip allow position and energy determination for each photon. We have demonstrated working strip detectors in the laboratory, and will present our measurements of the quasiparticle diffusion constant and the quasiparticle lifetime in tantalum, the aluminum quasiparticle lifetime, and the energy resolution of the detector. We will also discuss ideas for future detector designs and suggest ultimate performance goals for X-ray astronomy applications.

  16. Compact x-ray generator utilizing cerium-target tube for angiography

    NASA Astrophysics Data System (ADS)

    Sato, Eiichi; Tanaka, Etsuro; Mori, Hidezo; Kawai, Toshiaki; Ito, Fumihito; Ichimaru, Toshio; Sato, Shigehiro; Takayama, Kazuyoshi; Ido, Hideaki

    2004-11-01

    The cerium-target x-ray tube is useful in order to perform cone beam K-edge angiography because K-series characteristic x rays from the cerium target are absorbed effectively by iodine-based contrast mediums. The x-ray generator consists of a main controller and a unit with a high-voltage circuit and a fixed anode x-ray tube. The tube is a glass-enclosed diode with a cerium target and a 0.5 mm-thick beryllium window. The maximum tube voltage and current were 65 kV and 0.4 mA, respectively, and the focal-spot sizes were 1.3×0.9 mm. Cerium K-series characteristic x rays were left using a 3.0 mm-thick aluminum filter, and the x-ray intensity was 0.59 μC/kg at 1.0 m from the source with a tube voltage of 60 kV, a current of 0.40 mA, and an exposure time of 1.0 s. Angiography was performed with a computed radiography system using iodine-based microspheres 15 μm in diameter. In angiography of non-living animals, we observed fine blood vessels of approximately 100 μm with high contrasts.

  17. Generation of multi-color attosecond x-ray radiation through modulation compression

    SciTech Connect

    Qiang Ji; Wu Juhao

    2011-08-22

    In this paper, we propose a scheme to generate tunable multi-color attosecond coherent x-ray radiation. This scheme uses a modulation compression method to generate a multi-spike prebunched kilo-ampere peak current electron beam from a few tens ampere electron beam out of a linac. Such a beam transporting through a series of undulator radiators and bunch compressors generates multi-color coherent x-ray radiation. As an illustration, we present an example to generate two attosecond pulses with 2.2 nm and 3 nm coherent x-ray radiation wavelength and more than 200 MW peak power using a 50 A 200 nm laser seeded electron beam.

  18. Development of all-solid-state flash x-ray generator with photoconductive semiconductor switches.

    PubMed

    Xun, Ma; Jianjun, Deng; Hongwei, Liu; Jianqiang, Yuan; Jinfeng, Liu; Bing, Wei; Yanling, Qing; Wenhui, Han; Lingyun, Wang; Pin, Jiang; Hongtao, Li

    2014-09-01

    A compact, low-jitter, and high repetitive rate all-solid-state flash x-ray generator making use of photo conductive semiconductor switches was developed recently for the diagnostic purpose of some hydrokinetical experiments. The generator consisted of twelve stages of Blumlein pulse forming networks, and an industrial cold cathode diode was used to generate intense x-ray radiations with photon energy up to 220 keV. Test experiments showed that the generator could produce >1 kA electron beam currents and x-ray pulses with ~40 ns duration under 100 Hz repetitive rates at least (limited by the triggering laser on hand), also found was that the delay time of the cathode explosive emission is crucial to the energy transfer efficiency of the whole system. In addition, factors affecting the diode impedance, how the switching synchronization and diode impedance determining the allowable operation voltage were discussed.

  19. Development of all-solid-state flash x-ray generator with photoconductive semiconductor switches

    SciTech Connect

    Xun, Ma; Jianjun, Deng; Hongwei, Liu; Jianqiang, Yuan; Jinfeng, Liu; Bing, Wei; Yanling, Qing; Wenhui, Han; Lingyun, Wang; Pin, Jiang; Hongtao, Li

    2014-09-15

    A compact, low-jitter, and high repetitive rate all-solid-state flash x-ray generator making use of photo conductive semiconductor switches was developed recently for the diagnostic purpose of some hydrokinetical experiments. The generator consisted of twelve stages of Blumlein pulse forming networks, and an industrial cold cathode diode was used to generate intense x-ray radiations with photon energy up to 220 keV. Test experiments showed that the generator could produce >1 kA electron beam currents and x-ray pulses with ∼40 ns duration under 100 Hz repetitive rates at least (limited by the triggering laser on hand), also found was that the delay time of the cathode explosive emission is crucial to the energy transfer efficiency of the whole system. In addition, factors affecting the diode impedance, how the switching synchronization and diode impedance determining the allowable operation voltage were discussed.

  20. High-speed dental radiography achieved with a kilohertz-range pulsed x-ray generator

    SciTech Connect

    Takabe, Akihito; Yamamoto, Mariko; Sakamaki, Kimio

    1995-12-31

    The development of a high-intensity kilohertz-range pulsed x-ray generator and its application to dental radiography are described. The pulsed x-ray generator consisted of the following major components: a constant high-voltage power supply, a high-voltage main condenser, a hot-cathode triode, a DC power supply for the filament (hot cathode), and a grid controller. The main condenser of 0.5 {micro}F-100 kV in the pulser was charged from 50 to 70 kV by the power supply, and the electric charges in the condenser were discharged to the triode by the grid controller. To be exact, the tube voltage decreased during the discharging for generating pulsed x-rays, yet the maximum value was equivalent to the initial charging voltage of the main condenser. The maximum values of the tube current and the repetition rate were about 0.5 A and 30 kHz, respectively. The pulse width of the x-rays ranged from approximately 20 to 400 {micro}s, and the x-ray intensity with a charging voltage of 70 kV and a total resistance of 5.1 M{Omega} was about 0.83 {micro}C/kg at 1.0 m per pulse. Using this generator, high-speed dental radiography, e.g., delayed radiography and multiple-shot radiography, was performed.

  1. High-dose-rate stroboscopic x-ray generator with a hot-cathode triode

    NASA Astrophysics Data System (ADS)

    Sato, Eiichi; Ichimaru, Toshio; Sakamaki, Kimio; Takayama, Kazuyoshi; Tamakawa, Yoshiharu

    1997-12-01

    The construction and the fundamental studies of a high-dose- rate stroboscopic x-ray generator utilizing a hot-cathode radiation tube for high-speed radiography are described. This generator consists of the following essential components: a constant high-voltage power supply, an energy-storage oil condenser of about 0.1 (mu) F, a grid pulser, a dc power supply for the filament, and an x-ray tube. The x-ray tube is a glass-enclosed hot-cathode triode and is composed of the following major parts: an anode rod made of copper, a tungsten plate target, an iron focusing electrode, a tungsten hot- cathode (filament), a tungsten grid, and a glass tube body. The electron beams from the cathode are accelerated by both the grid and anode electrodes and are roughly converged to the target by the focusing electrode. In the present work, the storage condenser is charged up to 70 kV by the power supply, and the electric charges in the condenser are discharged repetitively to the x-ray tube by the grid pulser. Because the cathode current is increased by increasing the positive grid voltage, high-dose-rate repetitive x-rays are then produced. In this generator, the cathode current which is almost equivalent to the tube current is primarily regulated by the filament temperature (fulminate voltage). The pulse widths of x-rays were about 600 ns, and the maximum repetition rate was about 50 kHz. The cathode current was less than 3.1 angstrom, and the x-ray intensity had a value of 35.2 nC/kg at 0.5 m per pulse with a charging voltage of 70 kV and a filament voltage of 12 V.

  2. U-shape rotating anti-cathode compact X-ray generator: 20 times stronger than the commercially available X-ray source.

    PubMed

    Sakabe, N; Sakabe, K; Ohsawa, S; Sakai, T; Kobayakawa, H; Sugimura, T; Ikeda, M; Tawada, M; Watanabe, N; Sasaki, K; Wakatsuki, M

    2013-11-01

    A new type of U-shape anti-cathode X-ray generator in which the inner surface of a cylindrical target is irradiated by an electron beam has been made by modifying a conventional rotating anti-cathode X-ray generator whose brightness in the catalog is 12 kW mm(-2). The target material (Cu), target radius (50 mm) and rotating speed (6,000 r.p.m.) were not changed in this modification. A brightness of 52 kW mm(-2) was obtained by this U-shape-type X-ray generator. This means that the brightness of the new type is 4.3 times greater than that of the old unmodified one. Furthermore, the new-type X-ray generator yielded a brightness of 129 kW mm(-2) by adding a carbon coating on the Cu target. This means an overall increase of brightness of ten times. The original generator has the highest brightness in the generators of the same class (having a radius of 50 mm and rotation speed of 6,000 r.p.m.). Observations showed that Cu Kα counts at vertical incidence of the electron beam onto the surface of the new target, which is initially optically smooth, decrease as the surface is roughened by a severe thermal stress caused by strong electron beam exposure. Further observation reveals, however, that oblique incidence of the electron beam onto the roughened surface drastically increased the X-ray output and amounts to twice as much as that from a smooth surface at vertical incidence. Thus, at the present stage, an overall increase of brightness has been realised at a level 20 times stronger than that of the original commercially offered X-ray generator that we modified.

  3. Flash x-ray generator having a liquid-anode diode

    NASA Astrophysics Data System (ADS)

    Oizumi, Teiji; Sato, Eiichi; Shikoda, Arimitsu; Sagae, Michiaki; Takahashi, Kei; Tamakawa, Yoshiharu; Yanagisawa, Toru; Ojima, Hidenori; Takayama, Kazuyoshi; Fujiwara, Akihiro; Mitoya, Kanji

    1995-05-01

    The constructions and the fundamental studies of a flash x-ray generator having a liquid-anode diode are described. This flash x-ray generator consisted of the following essential components: a high-voltage power supply, a high-voltage pulser, a thyratron pulser as a trigger device, an oil diffusion pump, and a flash x-ray tube. The main condenser was negatively charged from 50 to 70 kV by the power supply, and the electric charges in the condenser were discharged to the x-ray tube after closing a gap switch by using the thyratron pulser. The flash x- ray tube was of a diode type having a mercury anode and a ferrite cathode. The pressure of the tube was primarily determined by the steam pressure of mercury as a function of temperature. The maximum output voltage from the pulser was about -1 times the charged voltage. The maximum tube voltage and current were approximately 60 kV and 3 kA, respectively, with a charged voltage of -60 kV and a space between the anode and cathode electrodes (AC space) of 2.0 mm. The pulse widths of flash x rays were about 50 ns, and the x-ray intensity measured by a thermoluminescence dosimeter had a value of about 2.5 (mu) C/kg at 0.3 m per pulse with a charged voltage of -70 kV and an AC space of 1.0 mm.

  4. Fast generation of virtual X-ray images for reconstruction of 3D anatomy.

    PubMed

    Ehlke, Moritz; Ramm, Heiko; Lamecker, Hans; Hege, Hans-Christian; Zachow, Stefan

    2013-12-01

    We propose a novel GPU-based approach to render virtual X-ray projections of deformable tetrahedral meshes. These meshes represent the shape and the internal density distribution of a particular anatomical structure and are derived from statistical shape and intensity models (SSIMs). We apply our method to improve the geometric reconstruction of 3D anatomy (e.g. pelvic bone) from 2D X-ray images. For that purpose, shape and density of a tetrahedral mesh are varied and virtual X-ray projections are generated within an optimization process until the similarity between the computed virtual X-ray and the respective anatomy depicted in a given clinical X-ray is maximized. The OpenGL implementation presented in this work deforms and projects tetrahedral meshes of high resolution (200.000+ tetrahedra) at interactive rates. It generates virtual X-rays that accurately depict the density distribution of an anatomy of interest. Compared to existing methods that accumulate X-ray attenuation in deformable meshes, our novel approach significantly boosts the deformation/projection performance. The proposed projection algorithm scales better with respect to mesh resolution and complexity of the density distribution, and the combined deformation and projection on the GPU scales better with respect to the number of deformation parameters. The gain in performance allows for a larger number of cycles in the optimization process. Consequently, it reduces the risk of being stuck in a local optimum. We believe that our approach will improve treatments in orthopedics, where 3D anatomical information is essential.

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

    NASA Astrophysics Data System (ADS)

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

    2016-05-01

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

  6. Explosive Device for Generation of Pulsed Fluxes of Soft X-Ray Radiation

    NASA Astrophysics Data System (ADS)

    Selemir, V. D.; Demidov, V. A.; Ivanovsky, A. V.; Yermolovich, V. F.; Kornilov, V. G.; Chelpanov, V. I.; Kazakov, S. A.; Vlasov, Y. V.; Orlov, A. P.

    2004-11-01

    The concept and realization of the explosive electrophysical device EMIR to generate soft x-ray radiation pulses are described. EMIR is based on the development of VNIIEF technologies in high-power flux compression generators, and on transforming systems based on lines with distributed parameters and current opening switches. Vacuum lines with magnetic insulation or water coaxial lines are considered for transmission of the energy pulses to the load. Transformation of magnetic energy to kinetic energy, thermalization and soft x-ray radiation are performed in a z-pinch with a double liner system.

  7. Demonstration of enhanced K-edge angiography using a cerium target x-ray generator

    SciTech Connect

    Sato, Eiichi; Tanaka, Etsuro; Mori, Hidezo; Kawai, Toshiaki; Ichimaru, Toshio; Sato, Shigehiro; Takayama, Kazuyoshi; Ido, Hideaki

    2004-11-01

    The cerium target x-ray generator is useful in order to perform enhanced K-edge angiography using a cone beam because K-series characteristic x rays from the cerium target are absorbed effectively by iodine-based contrast mediums. The x-ray generator consists of a main controller, a unit with a Cockcroft-Walton circuit and a fixed anode x-ray tube, and a personal computer. The tube is a glass-enclosed diode with a cerium target and a 0.5-mm-thick beryllium window. The maximum tube voltage and current were 65 kV and 0.4 mA, respectively, and the focal-spot sizes were 1.0x1.3 mm. Cerium K{alpha} lines were left using a barium sulfate filter, and the x-ray intensity was 0.48 {mu}C/kg at 1.0 m from the source with a tube voltage of 60 kV, a current of 0.40 mA, and an exposure time of 1.0 s. Angiography was performed with a computed radiography system using iodine-based microspheres. In coronary angiography of nonliving animals, we observed fine blood vessels of approximately 100 {mu}m with high contrasts.

  8. Short x-ray pulse generation using deflecting cavities at the Advanced Photon Source.

    SciTech Connect

    Sajaev, V.; Borland, M.; Chae, Y.-C.; Decker, G.; Dejus, R.; Emery, L.; Harkay, K.; Nassiri, A.; Shastri, S.; Waldschmidt, G.; Yang, B.; Anfinrud, P.; Dolgashev, V.; NIH; SLAC

    2007-11-11

    Storage-ring-based third-generation light sources can provide intense radiation pulses with durations as short as 100 ps. However, there is growing interest within the synchrotron radiation user community in performing experiments with much shorter X-ray pulses. Zholents et al. [Nucl. Instr. and Meth. A 425 (1999) 385] recently proposed using RF orbit deflection to generate sub-ps X-ray pulses. In this scheme, two deflecting cavities are used to deliver a longitudinally dependent vertical kick to the beam. An optical slit can then be used to slice out a short part of the radiation pulse. Implementation of this scheme is planned for one APS beamline in the near future. In this paper, we summarize our feasibility study of this method and the expected X-ray beam parameters. We find that a pulse length of less than two picoseconds can be achieved.

  9. Short X-ray pulse generation using deflecting cavities at the Advanced Photon Source

    NASA Astrophysics Data System (ADS)

    Sajaev, V.; Borland, M.; Chae, Y.-C.; Decker, G.; Dejus, R.; Emery, L.; Harkay, K.; Nassiri, A.; Shastri, S.; Waldschmidt, G.; Yang, B.; Anfinrud, P.; Dolgashev, V.

    2007-11-01

    Storage-ring-based third-generation light sources can provide intense radiation pulses with durations as short as 100 ps. However, there is growing interest within the synchrotron radiation user community in performing experiments with much shorter X-ray pulses. Zholents et al. [Nucl. Instr. and Meth. A 425 (1999) 385] recently proposed using RF orbit deflection to generate sub-ps X-ray pulses. In this scheme, two deflecting cavities are used to deliver a longitudinally dependent vertical kick to the beam. An optical slit can then be used to slice out a short part of the radiation pulse. Implementation of this scheme is planned for one APS beamline in the near future. In this paper, we summarize our feasibility study of this method and the expected X-ray beam parameters. We find that a pulse length of less than two picoseconds can be achieved.

  10. X-ray emission generated by laser-produced plasmas from dielectric nanostructured targets

    NASA Astrophysics Data System (ADS)

    Samsonova, Z.; Höfer, S.; Hoffmann, A.; Landgraf, B.; Zürch, M.; Uschmann, I.; Khaghani, D.; Rosmej, O.; Neumayer, P.; Röder, R.; Trefflich, L.; Ronning, C.; Förster, E.; Spielmann, C.; Kartashov, D.

    2017-03-01

    We present an experimental study of X-ray generation from nanostructured ZnO targets. Samples of different morphology ranging from nanowires to polished surfaces are irradiated by relativistically intense femtosecond laser pulses. X-ray emission of plasma is generated by 45 fs 130 mJ laser pulses at 400 nm with picosecond temporal contrast better than 10-9 interacting with an array of ZnO nanowires. The measured spectra indicate the existence of highly ionized states of Zn (up to He-like Zn). The obtained flux of ˜1010 photons per laser shot at the neutral Zn Kα energies around 8.65 keV and at the Zn Heα energies around 9 keV is almost 3 times higher for nanostructured targets compared to the reference polished sample and implies 10-4 conversion efficiency from the laser energy to the total energy of the emitted X-ray photons.

  11. Direct analysis of molybdenum target generated x-ray spectra with a portable device.

    PubMed

    Stumbo, S; Bottigli, U; Golosio, B; Oliva, P; Tangaro, S

    2004-10-01

    In routine applications, information about the photon flux of x-ray tubes is obtained from exposure measurements and cataloged spectra. This approach relies mainly on the assumption that the real spectrum is correctly approximated by the cataloged one, once the main characteristics of the tube such as voltage, target material, anode angle, and filters are taken account of. In practice, all this information is not always available. Moreover, x-ray tubes with the same characteristics may have different spectra. We describe an apparatus that should be useful for quality control in hospitals and for characterizing new radiographic systems. The apparatus analyzes the spectrum generated by an x-ray mammographic unit. It is based on a commercial CZT produced by AMPTEK Inc. and a set of tungsten collimator disks. The electronics of the CZT are modified so as to obtain a faster response. The signal is digitized using an analog to digital converter with a sampling frequency of up to 20 MHz. The whole signal produced by the x-ray tube is acquired and analyzed off-line in order to accurately recognize pile-up events and reconstruct the emitted spectrum. The energy resolution has been determined using a calibrated x-ray source. Spectra were validated by comparison of the HVL measured using an ionization chamber.

  12. Generation and dose distribution measurement of flash x-ray in KALI-5000 system

    NASA Astrophysics Data System (ADS)

    Menon, Rakhee; Roy, Amitava; Mitra, S.; Sharma, A.; Mondal, J.; Mittal, K. C.; Nagesh, K. V.; Chakravarthy, D. P.

    2008-10-01

    Flash x-ray generation studies have been carried out in KALI-5000 Pulse power system. The intense relativistic electron beam has been bombarded on a tantalum target at anode to produce flash x-ray via bremsstrahlung conversion. The typical electron beam parameter was 360 kV, 18 kA, and 100 ns, with a few hundreds of A/cm2 current density. The x-ray dose has been measured with calcium sulfate:dysposium (CaSO4:Dy) thermoluminescent dosimeter and the axial dose distribution has been characterized. It has been observed that the on axis dose falls of with distance ˜1/xn, where n varies from 1.8 to 1.85. A maximum on axis dose of 46 mrad has been measured at 1 m distance from the source. A plastic scintillator with optical fiber coupled to a photomultiplier tube has been developed to measure the x-ray pulse width. The typical x-ray pulse width varied from 50 to 80 ns.

  13. Generation and dose distribution measurement of flash x-ray in KALI-5000 system.

    PubMed

    Menon, Rakhee; Roy, Amitava; Mitra, S; Sharma, A; Mondal, J; Mittal, K C; Nagesh, K V; Chakravarthy, D P

    2008-10-01

    Flash x-ray generation studies have been carried out in KALI-5000 Pulse power system. The intense relativistic electron beam has been bombarded on a tantalum target at anode to produce flash x-ray via bremsstrahlung conversion. The typical electron beam parameter was 360 kV, 18 kA, and 100 ns, with a few hundreds of A/cm(2) current density. The x-ray dose has been measured with calcium sulfate:dysposium (CaSO(4):Dy) thermoluminescent dosimeter and the axial dose distribution has been characterized. It has been observed that the on axis dose falls of with distance approximately 1/x(n), where n varies from 1.8 to 1.85. A maximum on axis dose of 46 mrad has been measured at 1 m distance from the source. A plastic scintillator with optical fiber coupled to a photomultiplier tube has been developed to measure the x-ray pulse width. The typical x-ray pulse width varied from 50 to 80 ns.

  14. Generation and dose distribution measurement of flash x-ray in KALI-5000 system

    SciTech Connect

    Menon, Rakhee; Roy, Amitava; Mitra, S.; Sharma, A.; Mondal, J.; Mittal, K. C.; Nagesh, K. V.; Chakravarthy, D. P.

    2008-10-15

    Flash x-ray generation studies have been carried out in KALI-5000 Pulse power system. The intense relativistic electron beam has been bombarded on a tantalum target at anode to produce flash x-ray via bremsstrahlung conversion. The typical electron beam parameter was 360 kV, 18 kA, and 100 ns, with a few hundreds of A/cm{sup 2} current density. The x-ray dose has been measured with calcium sulfate:dysposium (CaSO{sub 4}:Dy) thermoluminescent dosimeter and the axial dose distribution has been characterized. It has been observed that the on axis dose falls of with distance {approx}1/x{sup n}, where n varies from 1.8 to 1.85. A maximum on axis dose of 46 mrad has been measured at 1 m distance from the source. A plastic scintillator with optical fiber coupled to a photomultiplier tube has been developed to measure the x-ray pulse width. The typical x-ray pulse width varied from 50 to 80 ns.

  15. Generation of bright isolated attosecond soft X-ray pulses driven by multicycle midinfrared lasers.

    PubMed

    Chen, Ming-Chang; Mancuso, Christopher; Hernández-García, Carlos; Dollar, Franklin; Galloway, Ben; Popmintchev, Dimitar; Huang, Pei-Chi; Walker, Barry; Plaja, Luis; Jaroń-Becker, Agnieszka A; Becker, Andreas; Murnane, Margaret M; Kapteyn, Henry C; Popmintchev, Tenio

    2014-06-10

    High harmonic generation driven by femtosecond lasers makes it possible to capture the fastest dynamics in molecules and materials. However, to date the shortest subfemtosecond (attosecond, 10(-18) s) pulses have been produced only in the extreme UV region of the spectrum below 100 eV, which limits the range of materials and molecular systems that can be explored. Here we experimentally demonstrate a remarkable convergence of physics: when midinfrared lasers are used to drive high harmonic generation, the conditions for optimal bright, soft X-ray generation naturally coincide with the generation of isolated attosecond pulses. The temporal window over which phase matching occurs shrinks rapidly with increasing driving laser wavelength, to the extent that bright isolated attosecond pulses are the norm for 2-µm driving lasers. Harnessing this realization, we experimentally demonstrate the generation of isolated soft X-ray attosecond pulses at photon energies up to 180 eV for the first time, to our knowledge, with a transform limit of 35 attoseconds (as), and a predicted linear chirp of 300 as. Most surprisingly, advanced theory shows that in contrast with as pulse generation in the extreme UV, long-duration, 10-cycle, driving laser pulses are required to generate isolated soft X-ray bursts efficiently, to mitigate group velocity walk-off between the laser and the X-ray fields that otherwise limit the conversion efficiency. Our work demonstrates a clear and straightforward approach for robustly generating bright isolated attosecond pulses of electromagnetic radiation throughout the soft X-ray region of the spectrum.

  16. Generation of bright isolated attosecond soft X-ray pulses driven by multicycle midinfrared lasers

    PubMed Central

    Chen, Ming-Chang; Mancuso, Christopher; Hernández-García, Carlos; Dollar, Franklin; Galloway, Ben; Popmintchev, Dimitar; Huang, Pei-Chi; Walker, Barry; Plaja, Luis; Jaroń-Becker, Agnieszka A.; Becker, Andreas; Murnane, Margaret M.; Kapteyn, Henry C.; Popmintchev, Tenio

    2014-01-01

    High harmonic generation driven by femtosecond lasers makes it possible to capture the fastest dynamics in molecules and materials. However, to date the shortest subfemtosecond (attosecond, 10−18 s) pulses have been produced only in the extreme UV region of the spectrum below 100 eV, which limits the range of materials and molecular systems that can be explored. Here we experimentally demonstrate a remarkable convergence of physics: when midinfrared lasers are used to drive high harmonic generation, the conditions for optimal bright, soft X-ray generation naturally coincide with the generation of isolated attosecond pulses. The temporal window over which phase matching occurs shrinks rapidly with increasing driving laser wavelength, to the extent that bright isolated attosecond pulses are the norm for 2-µm driving lasers. Harnessing this realization, we experimentally demonstrate the generation of isolated soft X-ray attosecond pulses at photon energies up to 180 eV for the first time, to our knowledge, with a transform limit of 35 attoseconds (as), and a predicted linear chirp of 300 as. Most surprisingly, advanced theory shows that in contrast with as pulse generation in the extreme UV, long-duration, 10-cycle, driving laser pulses are required to generate isolated soft X-ray bursts efficiently, to mitigate group velocity walk-off between the laser and the X-ray fields that otherwise limit the conversion efficiency. Our work demonstrates a clear and straightforward approach for robustly generating bright isolated attosecond pulses of electromagnetic radiation throughout the soft X-ray region of the spectrum. PMID:24850866

  17. X-ray comb generation from nuclear-resonance-stabilized x-ray free-electron laser oscillator for fundamental physics and precision metrology

    NASA Astrophysics Data System (ADS)

    Adams, B. W.; Kim, K.-J.

    2015-03-01

    An x-ray free-electron laser oscillator (XFELO) is a next-generation x-ray source, similar to free-electron laser oscillators at VUV and longer wavelengths but using crystals as high-reflectivity x-ray mirrors. Each output pulse from an XFELO is fully coherent with high spectral purity. The temporal coherence length can further be increased drastically, from picoseconds to microseconds or even longer, by phase-locking successive XFELO output pulses, using the narrow nuclear resonance lines of nuclei such as 57Fe as a reference. We show that the phase fluctuation due to the seismic activities is controllable and that due to spontaneous emission is small. The fluctuation of electron-bunch spacing contributes mainly to the envelope fluctuation but not to the phase fluctuation. By counting the number of standing-wave maxima formed by the output of the nuclear-resonance-stabilized (NRS) XFELO over an optically known length, the wavelength of the nuclear resonance can be accurately measured, possibly leading to a new length or frequency standard at x-ray wavelengths. A NRS-XFELO will be an ideal source for experimental x-ray quantum optics as well as other fundamental physics. The technique can be refined for other, narrower resonances such as 181Ta or 45Sc.

  18. X-Ray Comb Generation from Nuclear-Resonance-Stabilized X-Ray Free-Electron Laser Oscillator for Fundamental Physics and Precision Metrology

    SciTech Connect

    Adams, B. W.; Kim, K. -J.

    2015-03-31

    An x-ray free-electron laser oscillator (XFELO) is a next-generation x-ray source, similar to free-electron laser oscillators at VUV and longer wavelengths but using crystals as high-reflectivity x-ray mirrors. Each output pulse from an XFELO is fully coherent with high spectral purity. The temporal coherence length can further be increased drastically, from picoseconds to microseconds or even longer, by phase-locking successive XFELO output pulses, using the narrow nuclear resonance lines of nuclei such as Fe-57 as a reference. We show that the phase fluctuation due to the seismic activities is controllable and that due to spontaneous emission is small. The fluctuation of electron-bunch spacing contributes mainly to the envelope fluctuation but not to the phase fluctuation. By counting the number of standing-wave maxima formed by the output of the nuclear-resonance-stabilized (NRS) XFELO over an optically known length, the wavelength of the nuclear resonance can be accurately measured, possibly leading to a new length or frequency standard at x-ray wavelengths. A NRS-XFELO will be an ideal source for experimental x-ray quantum optics as well as other fundamental physics. The technique can be refined for other, narrower resonances such as Ta-181 or Sc-45.

  19. On angiography with a Thomson laser-electron X-ray generator

    NASA Astrophysics Data System (ADS)

    Vinogradov, A. V.; Vinogradov, S. L.; D’yachkov, N. V.; Polunina, A. V.; Postnov, A. A.

    2017-02-01

    We consider a possibility of application of laser-electron X-ray generators for diagnosing the vessel status of internal organs. It is shown that modern lasers and linear accelerators can be used for the development of angiographic instruments of a new type with an increased spatial and temporal resolution while maintaining or reducing the radiation load on the patient and medical staff. Such improvements in diagnostic and ambient factors cannot be achieved with the use of X-ray tubes. All particular estimates and calculations have been performed for a contrast agent based on iodine compounds.

  20. Tuning the Performance of Organic Spintronic Devices Using X-Ray Generated Traps

    NASA Astrophysics Data System (ADS)

    Rybicki, J.; Lin, R.; Wang, F.; Wohlgenannt, M.; He, C.; Sanders, T.; Suzuki, Y.

    2012-08-01

    X rays produced during electron-beam deposition of metallic electrodes drastically change the performance of organic spintronic devices. The x rays generate traps with an activation energy of ≈0.5eV in a commonly used organic. These traps lead to a dramatic decrease in spin-diffusion length in organic spin valves. In organic magnetoresistive (OMAR) devices, however, the traps strongly enhance magnetoresistance. OMAR is an intrinsic magnetotransport phenomenon and does not rely on spin injection. We discuss our observations in the framework of currently existing theories.

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

    SciTech Connect

    Yamada, H.; Amano, D.; Miyade, H.

    1995-12-31

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

  2. Ultraviolet surprise: Efficient soft x-ray high-harmonic generation in multiply ionized plasmas.

    PubMed

    Popmintchev, Dimitar; Hernández-García, Carlos; Dollar, Franklin; Mancuso, Christopher; Pérez-Hernández, Jose A; Chen, Ming-Chang; Hankla, Amelia; Gao, Xiaohui; Shim, Bonggu; Gaeta, Alexander L; Tarazkar, Maryam; Romanov, Dmitri A; Levis, Robert J; Gaffney, Jim A; Foord, Mark; Libby, Stephen B; Jaron-Becker, Agnieszka; Becker, Andreas; Plaja, Luis; Murnane, Margaret M; Kapteyn, Henry C; Popmintchev, Tenio

    2015-12-04

    High-harmonic generation is a universal response of matter to strong femtosecond laser fields, coherently upconverting light to much shorter wavelengths. Optimizing the conversion of laser light into soft x-rays typically demands a trade-off between two competing factors. Because of reduced quantum diffusion of the radiating electron wave function, the emission from each species is highest when a short-wavelength ultraviolet driving laser is used. However, phase matching--the constructive addition of x-ray waves from a large number of atoms--favors longer-wavelength mid-infrared lasers. We identified a regime of high-harmonic generation driven by 40-cycle ultraviolet lasers in waveguides that can generate bright beams in the soft x-ray region of the spectrum, up to photon energies of 280 electron volts. Surprisingly, the high ultraviolet refractive indices of both neutral atoms and ions enabled effective phase matching, even in a multiply ionized plasma. We observed harmonics with very narrow linewidths, while calculations show that the x-rays emerge as nearly time-bandwidth-limited pulse trains of ~100 attoseconds.

  3. The Ultraviolet Surprise. Efficient Soft X-Ray High Harmonic Generation in Multiply-Ionized Plasmas

    DOE PAGES

    Popmintchev, Dimitar; Hernandez-Garcia, Carlos; Dollar, Franklin; ...

    2015-12-04

    High-harmonic generation is a universal response of matter to strong femtosecond laser fields, coherently upconverting light to much shorter wavelengths. Optimizing the conversion of laser light into soft x-rays typically demands a trade-off between two competing factors. Reduced quantum diffusion of the radiating electron wave function results in emission from each species which is highest when a short-wavelength ultraviolet driving laser is used. But, phase matching—the constructive addition of x-ray waves from a large number of atoms—favors longer-wavelength mid-infrared lasers. We identified a regime of high-harmonic generation driven by 40-cycle ultraviolet lasers in waveguides that can generate bright beams inmore » the soft x-ray region of the spectrum, up to photon energies of 280 electron volts. Surprisingly, the high ultraviolet refractive indices of both neutral atoms and ions enabled effective phase matching, even in a multiply ionized plasma. We observed harmonics with very narrow linewidths, while calculations show that the x-rays emerge as nearly time-bandwidth–limited pulse trains of ~100 attoseconds.« less

  4. The Ultraviolet Surprise. Efficient Soft X-Ray High Harmonic Generation in Multiply-Ionized Plasmas

    SciTech Connect

    Popmintchev, Dimitar; Hernandez-Garcia, Carlos; Dollar, Franklin; Mancuso, Christopher; Perez-Hernandez, Jose A.; Chen, Ming-Chang; Hankla, Amelia; Gao, Xiaohui; Shim, Bonggu; Gaeta, Alexander L.; Tarazkar, Maryam; Romanov, Dmitri A.; Levis, Robert J.; Gaffney, Jim A.; Foord, Mark; Libby, Stephen B.; Jaron-Becker, Agnieskzka; Becker, Andreas; Plaja, Luis; Muranane, Margaret M.; Kapteyn, Henry C.; Popmintchev, Tenio

    2015-12-04

    High-harmonic generation is a universal response of matter to strong femtosecond laser fields, coherently upconverting light to much shorter wavelengths. Optimizing the conversion of laser light into soft x-rays typically demands a trade-off between two competing factors. Reduced quantum diffusion of the radiating electron wave function results in emission from each species which is highest when a short-wavelength ultraviolet driving laser is used. But, phase matching—the constructive addition of x-ray waves from a large number of atoms—favors longer-wavelength mid-infrared lasers. We identified a regime of high-harmonic generation driven by 40-cycle ultraviolet lasers in waveguides that can generate bright beams in the soft x-ray region of the spectrum, up to photon energies of 280 electron volts. Surprisingly, the high ultraviolet refractive indices of both neutral atoms and ions enabled effective phase matching, even in a multiply ionized plasma. We observed harmonics with very narrow linewidths, while calculations show that the x-rays emerge as nearly time-bandwidth–limited pulse trains of ~100 attoseconds.

  5. Excitation of XPS spectra from nanoscaled particles by local generation of x-rays

    SciTech Connect

    Mallinson, Christopher F.; Castle, James E.

    2015-09-15

    In preliminary work, the authors have shown that use of an aluminum substrate to support a distribution of copper particles enables their characteristic photoelectrons to be observed within the Auger electron spectrum generated by an incident electron beam. This observation raises the possibility of the use of chemical shifts and the corresponding Auger parameter to identify the chemical states present on the surface of individual submicrometer particles within a mixture. In this context, the technique has an advantage in that, unlike conventional Auger electron spectroscopy, the electron beam does not dwell on the particle but on the substrate adjacent to it. Given the importance, for both medical and toxicological reasons, of the surface composition of such particles, the authors have continued to explore the potential of this development. In this contribution, the authors show that proximal excitation of x-rays is equally successful with magnesium substrates. In some regions of the x-ray photoelectron spectrum, the much larger Auger peaks generated by the electron beam can cause inconvenient clustering of Auger and photoelectron peaks. As in conventional x-ray photoelectron spectroscopy, the ability to switch between Al and Mg sources is useful in such situations. In this context, the authors have extended the studies to iron particles where the authors show that use of Al or Mg substrates, as necessary, can make a contribution to clear identification of individual components in the Fe 2p peaks. For this development in electron spectroscopy to achieve its full potential, it is necessary to optimize the beam conditions used to generate the local x-ray to give good selectivity of a given particle. Measurements made in support of this will be given. Of greater concern is a possible problem of local heating associated with x-ray generation. The authors continue to explore this problem and report some progress in minimizing heating of the particle while maintaining

  6. X-ray-generated heralded macroscopical quantum entanglement of two nuclear ensembles

    PubMed Central

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

    2016-01-01

    Heralded entanglement between macroscopical samples is an important resource for present quantum technology protocols, allowing quantum communication over large distances. In such protocols, optical photons are typically used as information and entanglement carriers between macroscopic quantum memories placed in remote locations. Here we investigate theoretically a new implementation which employs more robust x-ray quanta to generate heralded entanglement between two crystal-hosted macroscopical nuclear ensembles. Mössbauer nuclei in the two crystals interact collectively with an x-ray spontaneous parametric down conversion photon that generates heralded macroscopical entanglement with coherence times of approximately 100 ns at room temperature. The quantum phase between the entangled crystals can be conveniently manipulated by magnetic field rotations at the samples. The inherent long nuclear coherence times allow also for mechanical manipulations of the samples, for instance to check the stability of entanglement in the x-ray setup. Our results pave the way for first quantum communication protocols that use x-ray qubits. PMID:27640348

  7. X-ray-generated heralded macroscopical quantum entanglement of two nuclear ensembles

    NASA Astrophysics Data System (ADS)

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

    2016-09-01

    Heralded entanglement between macroscopical samples is an important resource for present quantum technology protocols, allowing quantum communication over large distances. In such protocols, optical photons are typically used as information and entanglement carriers between macroscopic quantum memories placed in remote locations. Here we investigate theoretically a new implementation which employs more robust x-ray quanta to generate heralded entanglement between two crystal-hosted macroscopical nuclear ensembles. Mössbauer nuclei in the two crystals interact collectively with an x-ray spontaneous parametric down conversion photon that generates heralded macroscopical entanglement with coherence times of approximately 100 ns at room temperature. The quantum phase between the entangled crystals can be conveniently manipulated by magnetic field rotations at the samples. The inherent long nuclear coherence times allow also for mechanical manipulations of the samples, for instance to check the stability of entanglement in the x-ray setup. Our results pave the way for first quantum communication protocols that use x-ray qubits.

  8. Generation-X: An X-ray observatory designed to observe first light objects

    NASA Astrophysics Data System (ADS)

    Windhorst, Rogier A.; Cameron, R. A.; Brissenden, R. J.; Elvis, M. S.; Fabbiano, G.; Gorenstein, P.; Reid, P. B.; Schwartz, D. A.; Bautz, M. W.; Figueroa-Feliciano, E.; Petre, R.; White, N. E.; Zhang, W. W.

    2006-03-01

    The new cosmological frontier will be the study of the very first stars, galaxies and black holes in the early Universe. These objects are invisible to the current generation of X-ray telescopes, such as Chandra. In response, the Generation-X ("Gen-X") Vision Mission has been proposed as a future X-ray observatory which will be capable of detecting the earliest objects. X-ray imaging and spectroscopy of such faint objects demands a large collecting area and high angular resolution. The Gen-X mission plans 100 m 2 collecting area at 1 keV (1000× that of Chandra), and with an angular resolution of 0.1″. The Gen-X mission will operate at Sun-Earth L2, and might involve four 8 m diameter telescopes or even a single 20 m diameter telescope. To achieve the required effective area with reasonable mass, very lightweight grazing incidence X-ray optics must be developed, having an areal density 100× lower than in Chandra, with mirrors as thin as 0.1 mm requiring active on-orbit figure control. The suite of available detectors for Gen-X should include a large-area high resolution imager, a cryogenic imaging spectrometer, and a grating spectrometer. We discuss use of Gen-X to observe the birth of the first black holes, stars and galaxies, and trace their cosmic evolution.

  9. Coherent Soft X-Ray Generation in the Water Window with the EEHG Scheme

    SciTech Connect

    Xiang, D; Stupakov, G.; /SLAC

    2009-05-26

    Recently a scheme entitled echo-enabled harmonic generation (EEHG) was proposed for producing short wavelength FEL radiation that allows far higher harmonic numbers to be accessed as compared with the normal limit arising from incoherent energy spread. In this paper we study the feasibility of a single EEHG stage to generate coherent radiation in the 'water window' (2--4 nm wavelength) directly from a UV seed laser at 190-nm wavelength. We present time-dependent simulation results which demonstrate that the single-stage EEHG FEL can generate high power soft x-ray radiation in the water window with narrow bandwidth close to Fourier transform limit directly from a UV seed laser. The schemes to generate short x-ray pulse from femtosecond to attosecond using EEHG FEL are also discussed.

  10. Characterization of neutron yield and x-ray spectra of a High Flux Neutron Generator (HFNG)

    NASA Astrophysics Data System (ADS)

    Nnamani, Nnaemeka; HFNG Collaboration

    2015-04-01

    The High Flux Neutron Generator (HFNG) is a DD plasma-based source, with a self-loading target intended for fundamental science and engineering applications, including 40 Ar/39 Ar geochronology, neutron cross section measurements, and radiation hardness testing of electronics. Our first estimate of the neutron yield, based on the population of the 4.486 hour 115 In isomer gave a neutron yield of the order 108 n/sec; optimization is ongoing to achieve the design target of 1011 n/sec. Preliminary x-ray spectra showed prominent energy peaks which are likely due to atomic line-emission from back-streaming electrons accelerated up to 100 keV impinging on various components of the HFNG chamber. Our x-ray and neutron diagnostics will aid us as we continue to evolve the design to suppress back-streaming electrons, necessary to achieve higher plasma beam currents, and thus higher neutron flux. This talk will focus on the characterization of the neutron yield and x-ray spectra during our tests. A collimation system is being installed near one of the chamber ports for improved observation of the x-ray spectra. This work is supported by NSF Grant No. EAR-0960138, U.S. DOE LBNL Contract No. DE-AC02-05CH11231, U.S. DOE LLNL Contract No. DE-AC52-07NA27344, and the UC Office of the President Award 12-LR-238745.

  11. X-Ray Lasers

    ERIC Educational Resources Information Center

    Chapline, George; Wood, Lowell

    1975-01-01

    Outlines the prospects of generating coherent x rays using high-power lasers and indentifies problem areas in their development. Indicates possible applications for coherent x rays in the fields of chemistry, biology, and crystallography. (GS)

  12. The Generation-X X-ray Observatory Vision Mission and Technology Study

    NASA Technical Reports Server (NTRS)

    Figueroa-Feliciano, Enectali

    2004-01-01

    The new frontier in astrophysics is the study of the birth and evolution of the first stars, galaxies and black holes in the early Universe. X-ray astronomy opens a window into these objects by studying the emission from black holes, supernova explosions and the gamma-ray burst afterglows of massive stars. However, such objects are beyond the grasp of current or near-future observatories. X-ray imaging and spectroscopy of such distant objects will require an X-ray telescope with large collecting area and high angular resolution. Our team has conceived the Generation-X Vision Mission based on an X-ray observatory with 100 sq m collecting area at 1 keV (1000 times larger than Chandra) and 0.1 arcsecond angular resolution (several times better than Chandra and 50 times better than the Constellation-X resolution goal). Such an observatory would be capable of detecting the earliest black holes and galaxies in the Universe, and will also study extremes of density, gravity, magnetic fields, and kinetic energy which cannot be created in laboratories. NASA has selected the Generation-X mission for study under its Vision Mission Program. We describe the studies being performed to develop the mission concept and define candidate technologies and performance requirements for Generation-X. The baseline Generation-X mission involves four 8m diameter X-ray telescopes operating at Sun-Earth L2. We trade against an alternate concept of a single 26m diameter telescope with focal plane instruments on a separate spacecraft. A telescope of this size will require either robotic or human-assisted in-flight assembly. The required effective area implies that extremely lightweight grazing incidence X-ray optics must be developed. To achieve the required aerial density of at least 100 times lower than in Chandra, we will study 0.1mm thick mirrors which have active on-orbit figure control. We discuss the suite of required detectors, including a large FOV high angular resolution imager, a

  13. Adaptive grazing incidence optics for the next generation of x-ray observatories

    NASA Astrophysics Data System (ADS)

    Lillie, C.; Pearson, D.; Plinta, A.; Metro, B.; Lintz, E.; Shropshire, D.; Danner, R.

    2010-09-01

    Advances in X-ray astronomy require high spatial resolution and large collecting area. Unfortunately, X-ray telescopes with grazing incidence mirrors require hundreds of concentric mirror pairs to obtain the necessary collecting area, and these mirrors must be thin shells packed tightly together... They must also be light enough to be placed in orbit with existing launch vehicles, and able to be fabricated by the thousands for an affordable cost. The current state of the art in X-ray observatories is represented by NASA's Chandra X-ray observatory with 0.5 arc-second resolution, but only 400 cm2 of collecting area, and by ESA's XMM-Newton observatory with 4,300 cm2 of collecting area but only 15 arc-second resolution. The joint NASA/ESA/JAXA International X-ray Observatory (IXO), with {15,000 cm2 of collecting area and 5 arc-second resolution which is currently in the early study phase, is pushing the limits of passive mirror technology. The Generation-X mission is one of the Advanced Strategic Mission Concepts that NASA is considering for development in the post-2020 period. As currently conceived, Gen-X would be a follow-on to IXO with a collecting area >= 50 m2, a 60-m focal length and 0.1 arc-second spatial resolution. Gen-X would be launched in {2030 with a heavy lift Launch Vehicle to an L2 orbit. Active figure control will be necessary to meet the challenging requirements of the Gen-X optics. In this paper we present our adaptive grazing incidence mirror design and the results from laboratory tests of a prototype mirror.

  14. Intense high repetition rate Mo Kα x-ray source generated from laser solid interaction for imaging application.

    PubMed

    Huang, K; Li, M H; Yan, W C; Guo, X; Li, D Z; Chen, Y P; Ma, Y; Zhao, J R; Li, Y F; Zhang, J; Chen, L M

    2014-11-01

    We report an efficient Mo Kα x-ray source produced by interaction of femtosecond Ti: sapphire laser pulses with a solid Molybdenum target working at 1 kHz repetition rate. The generated Mo Kα x-ray intensity reaches to 4.7 × 10(10) photons sr(-1) s(-1), corresponding to an average power of 0.8 mW into 2π solid angle. The spatial resolution of this x-ray source is measured to be 26 lp/mm. With the high flux and high spatial resolution characteristics, high resolving in-line x-ray radiography was realized on test objects and large size biological samples within merely half a minute. This experiment shows the possibility of laser plasma hard x-ray source as a new low cost and high resolution system for radiography and its ability of ultrafast x-ray pump-probe study of matter.

  15. Design study of Thomson Laser-Electron X-ray Generator (LEX) for Millisecond Angiography

    NASA Astrophysics Data System (ADS)

    Artyukov, I. A.; Bessonov, E. G.; Feshchenko, R. M.; Gorbunkov, M. V.; Maslova, Yu Ya; Popov, N. L.; Dyachkov, N. V.; Postnov, A. A.; Vinogradov, S. L.; Vinogradov, A. V.

    2017-01-01

    In this concept study a laser-electron X-ray generator (LEX) is considered for the medical imaging of the inner vessel structure. It is demonstrated that the modern lasers and linear electron accelerators are suitable for the design of the new generation of angiography medical equipment combining higher spatial and time resolution with the reduced patient dose. Angiography setup based on LEXG can make use of different contrast media (iodine, gadolinium) working on absorption edge due to the narrow tuneable spectrum which is not possible with conventional X-ray tubes. In the present study all estimations are made for iodine-based contrast agents. The conclusion is that modern technologies allow practical implementation of LEX for angiography based on multibunch linear accelerator and photon storage device.

  16. The ARC-EN-CIEL French 4th Generation Light Source

    SciTech Connect

    Bruni, C.; Couprie, M. E.; Chubar, O.; Loulergue, A.; Nahon, L.; Carre, B.; Garzella, D.; Labat, M.; Lambert, G.; Monot, P.; Jablonka, M.; Meot, F.; Ortega, J. M.; Nutarelli, D.

    2007-01-19

    ARC-EN-CIEL (Accelerator-Radiation Complex for Enhanced Coherent Intense Extended Light) proposal is based on a CW 1 GeV superconducting linear accelerator delivering high charge, subpicosecond, low emittance electron bunches with a high repetition rate (1 kHz). The FEL uses High Harmonics Generation in gases in a High Gain Harmonic Generation scheme, leading to a rather compact solution. The radiation extends down to 0.8 nm with the non-linear harmonics and reproduces the good longitudinal and transverse coherence of the harmonics generated in gas. Optional beam loops, foreseen to increase the beam current or the energy, will accommodate infrared CSR source, femtosecond undulator sources in the VUV and X-ray ranges, and a FEL oscillator in the 10 nm range. An important synergy is expected between accelerator and laser communities, in particular for electron plasma acceleration tests.

  17. Attosecond x-ray source generation from two-color polarized gating plasmonic field enhancement

    SciTech Connect

    Feng, Liqiang; Yuan, Minghu; Chu, Tianshu

    2013-12-15

    The plasmonic field enhancement from the vicinity of metallic nanostructures as well as the polarization gating technique has been utilized to the generation of the high order harmonic and the single attosecond x-ray source. Through numerical solution of the time-dependent Schrödinger equation, for moderate the inhomogeneity and the polarized angle of the two fields, we find that not only the harmonic plateau has been extended and enhanced but also the single short quantum path has been selected to contribute to the harmonic. As a result, a series of 50 as pulses around the extreme ultraviolet and the x-ray regions have been obtained. Furthermore, by investigating the other parameters effects on the harmonic emission, we find that this two-color polarized gating plasmonic field enhancement scheme can also be achieved by the multi-cycle pulses, which is much better for experimental realization.

  18. Flexible Field Emitter for X-ray Generation by Implanting CNTs into Nickel Foil

    NASA Astrophysics Data System (ADS)

    Sun, Bin; Wang, Yan; Ding, Guifu

    2016-09-01

    This paper reports on a flexible Ni micro wire with CNTs embedded into its surface. By using micromachining technology, for the first time, we could implant nanoscale materials into micro-scale metal substrate at room temperature. Thanks to the effective direct contact and the strong interactions between CNTs and the substrate, field emission current of 1.11 mA (current density of 22.2 mA/cm2) could be achieved from the micro wire. Moreover, the wire shows excellent mechanical properties for large amplitude bending, which is beneficial for geometric designing. To check the practical application of the wire, a simplified X-ray imaging system was set up by modifying a conventional tube. The gray shade that appears on the sensitive film after being exposed to the radiation confirms the X-ray generation.

  19. X-ray harmonics rejection on third-generation synchrotron sources using compound refractive lenses.

    PubMed

    Polikarpov, Maxim; Snigireva, Irina; Snigirev, Anatoly

    2014-05-01

    A new method of harmonics rejection based on X-ray refractive optics has been proposed. Taking into account the fact that the focal distance of the refractive lens is energy-dependent, the use of an off-axis illumination of the lens immediately leads to spatial separation of the energy spectrum by focusing the fundamental harmonic at the focal point and suppressing the unfocused high-energy radiation with a screen absorber or slit. The experiment was performed at the ESRF ID06 beamline in the in-line geometry using an X-ray transfocator with compound refractive lenses. Using this technique the presence of the third harmonic has been reduced to 10(-3). In total, our method enabled suppression of all higher-order harmonics to five orders of magnitude using monochromator detuning. The method is well suited to third-generation synchrotron radiation sources and is very promising for the future ultimate storage rings.

  20. Characterization of a next-generation piezo bimorph X-ray mirror for synchrotron beamlines

    PubMed Central

    Alcock, Simon G.; Nistea, Ioana; Sutter, John P.; Sawhney, Kawal; Fermé, Jean-Jacques; Thellièr, Christophe; Peverini, Luca

    2015-01-01

    Piezo bimorph mirrors are versatile active optics used on many synchrotron beamlines. However, many bimorphs suffer from the ‘junction effect’: a periodic deformation of the optical surface which causes major aberrations to the reflected X-ray beam. This effect is linked to the construction of such mirrors, where piezo ceramics are glued directly below the thin optical substrate. In order to address this problem, a next-generation bimorph with piezos bonded to the side faces of a monolithic substrate was developed at Thales-SESO and optimized at Diamond Light Source. Using metrology feedback from the Diamond-NOM, the optical slope error was reduced to ∼0.5 µrad r.m.s. for a range of ellipses. To maximize usability, a novel holder was built to accommodate the substrate in any orientation. When replacing a first-generation bimorph on a synchrotron beamline, the new mirror significantly improved the size and shape of the reflected X-ray beam. Most importantly, there was no evidence of the junction effect even after eight months of continuous beamline usage. It is hoped that this new design will reinvigorate the use of active bimorph optics at synchrotron and free-electron laser facilities to manipulate and correct X-ray wavefronts. PMID:25537582

  1. Flash water-window x-ray generator with a ferrite capillary

    NASA Astrophysics Data System (ADS)

    Sato, Eiichi; Sagae, Michiaki; Ichimaru, Toshio; Takayama, Kazuyoshi; Sakamaki, Kimio; Tamakawa, Yoshiharu

    1997-12-01

    The fundamental study on a flash water-window x-ray generator is described. This generator is composed of a high-voltage power supply, a polarity-inversion high-voltage pulser, a krytron pulser as a trigger device, an oil-diffusion pump, and a vacuum chamber with a capillary. A combined ceramic condenser of about 5 nF in the pulser is charged up to 70 kV by the power supply, and the electric charges in the condenser are discharged to the capillary in the tube after closing a gap switch by the krytron pulser. In the present work, the chamber is evacuated by the pump with a pressure of about 1 by 10-3 Pa, and the titanium anode and cathode electrodes are employed to produce L-series characteristic x rays in the water-window range. The diameter and the length of the ferrite capillary are 2.0 and 30 mm, respectively. Both the cathode voltage and the discharge current displayed damped oscillations. The peak values of the voltage and current increased when the charging voltage was increased, and their maximum values were minus 24 kV and 2.8 kA, respectively. The pulse durations of the water-window x-rays were nearly equivalent to those of the damped oscillations of the voltage and current, and their values were less than 10 microseconds.

  2. Characterization of a next-generation piezo bimorph X-ray mirror for synchrotron beamlines.

    PubMed

    Alcock, Simon G; Nistea, Ioana; Sutter, John P; Sawhney, Kawal; Fermé, Jean Jacques; Thellièr, Christophe; Peverini, Luca

    2015-01-01

    Piezo bimorph mirrors are versatile active optics used on many synchrotron beamlines. However, many bimorphs suffer from the `junction effect': a periodic deformation of the optical surface which causes major aberrations to the reflected X-ray beam. This effect is linked to the construction of such mirrors, where piezo ceramics are glued directly below the thin optical substrate. In order to address this problem, a next-generation bimorph with piezos bonded to the side faces of a monolithic substrate was developed at Thales-SESO and optimized at Diamond Light Source. Using metrology feedback from the Diamond-NOM, the optical slope error was reduced to ∼ 0.5 µrad r.m.s. for a range of ellipses. To maximize usability, a novel holder was built to accommodate the substrate in any orientation. When replacing a first-generation bimorph on a synchrotron beamline, the new mirror significantly improved the size and shape of the reflected X-ray beam. Most importantly, there was no evidence of the junction effect even after eight months of continuous beamline usage. It is hoped that this new design will reinvigorate the use of active bimorph optics at synchrotron and free-electron laser facilities to manipulate and correct X-ray wavefronts.

  3. The generation of rapid solar flare hard X-ray and microwave fluctuations in current sheets

    NASA Astrophysics Data System (ADS)

    Holman, Gordon D.

    The generation of rapid fluctuations, or spikes, in hard X-ray and microwave bursts via the disruption of electron heating and acceleration in current sheets is studied. It is found that 20 msec hard X-ray fluctuations can be thermally generated in a current sheet if the resistivity in the sheet is highly anomalous, the plasma density in the emitting region is relatively high, and the volume of the emitting region is greater than that of the current sheet. A specific mechanism for producing the fluctuations, involving heating in the presence of ion acoustic turbulence and a constant driving electric field, and interruption of the heating by a strong two-stream instability, is discussed. Variations upon this mechanism are also discussed. This mechanism also modulates electron acceleration, as required for the microwave spike emission. If the hard X-ray emission at energies less than approx. 1000 keV is nonthermal bremsstrahlung, the coherent modulation of electron acceleration in a large number of current sheets is required.

  4. X-ray grating interferometer for imaging at a second-generation synchrotron radiation source

    NASA Astrophysics Data System (ADS)

    Herzen, Julia; Beckmann, Felix; Donath, Tilman; Ogurreck, Malte; David, Christian; Pfeiffer, Franz; Mohr, Jürgen; Reznikova, Elena; Riekehr, Stefan; Haibel, Astrid; Schulz, Georg; Müller, Bert; Schreyer, Andreas

    2010-09-01

    X-ray phase-contrast radiography and tomography enables to increase contrast for weakly absorbing materials. Recently, x-ray grating interferometers were developed which extend the possibility of phase-contrast imaging from highly brilliant radiation sources like third-generation synchrotron even to non-coherent sources. Here, we present a setup of an x-ray grating interferometer designed and installed at low-coherence wiggler source at the GKSS beamline W2 (HARWI II) operated at the second-generation synchrotron storage ring DORIS at the Deutsches Elektronen-Synchrotron (DESY, Hamburg, Germany). The beamline is dedicated to imaging in materials science. Equipped with the grating interferometer, it is the first synchrotron radiation beamline with a three-grating setup combining the advantages of phase-contrast imaging with monochromatic radiation with very high flux and a sufficiently large field of view for centimeter sized objects. Examples of radiography on laser-welded aluminum and magnesium joints are presented to demonstrate the high potential of the new gratingbased setup in the field of materials science. In addition, the results of an off-axis phase-contrast tomography of a human urethra with 15 mm in diameter are presented showing internal structures, which cannot be resolved by the conventional tomography in absorption mode.

  5. The generation of rapid solar flare hard X-ray and microwave fluctuations in current sheets

    NASA Technical Reports Server (NTRS)

    Holman, Gordon D.

    1986-01-01

    The generation of rapid fluctuations, or spikes, in hard X-ray and microwave bursts via the disruption of electron heating and acceleration in current sheets is studied. It is found that 20 msec hard X-ray fluctuations can be thermally generated in a current sheet if the resistivity in the sheet is highly anomalous, the plasma density in the emitting region is relatively high, and the volume of the emitting region is greater than that of the current sheet. A specific mechanism for producing the fluctuations, involving heating in the presence of ion acoustic turbulence and a constant driving electric field, and interruption of the heating by a strong two-stream instability, is discussed. Variations upon this mechanism are also discussed. This mechanism also modulates electron acceleration, as required for the microwave spike emission. If the hard X-ray emission at energies less than approx. 1000 keV is nonthermal bremsstrahlung, the coherent modulation of electron acceleration in a large number of current sheets is required.

  6. Theoretical analysis of hard x-ray generation by nonperturbative interaction of ultrashort light pulses with a metal

    PubMed Central

    Weisshaupt, Jannick; Juvé, Vincent; Holtz, Marcel; Woerner, Michael; Elsaesser, Thomas

    2015-01-01

    The interaction of intense femtosecond pulses with metals allows for generating ultrashort hard x-rays. In contrast to plasma theories, tunneling from the target into vacuum is introduced as electron generation step, followed by vacuum acceleration in the laser field and re-entrance into the target to generate characteristic x-rays and Bremsstrahlung. For negligible space charge in vacuum, the Kα flux is proportional to the incident intensity and the wavelength squared, suggesting a strong enhancement of the x-ray flux by mid-infrared driving pulses. This prediction is in quantitative agreement with experiments on femtosecond Cu Kα generation. PMID:26798790

  7. Design of a Nb3Sn Magnet for a 4th Generation ECR Ion Source

    SciTech Connect

    Prestemon, S,; Trillaud, F.; Caspi, S.; Ferracin, P.; Sabbi, G. L.; Lyneis, C. M.; Leitner, D.; Todd, D. S.; Hafalia, R.

    2008-08-17

    The next generation of Electron Cyclotron Resonant (ECR) ion sources are expected to operate at a heating radio frequency greater than 40 GHz. The existing 3rd generation systems, exemplified by the state of the art system VENUS, operate in the 10-28 GHz range, and use NbTi superconductors for the confinement coils. The magnetic field needed to confine the plasma scales with the rf frequency, resulting in peak fields on the magnets of the 4th generation system in excess of 10 T. High field superconductors such as Nb{sub 3}Sn must therefore be considered. The magnetic design of a 4th. generation ECR ion source operating at an rf frequency of 56 GHz is considered. The analysis considers both internal and external sextupole configurations, assuming commercially available Nb{sub 3}Sn material properties. Preliminary structural design issues are discussed based on the forces and margins associated with the coils in the different configurations, leading to quantitative data for the determination of a final magnet design.

  8. Long pulse Soft X-ray Emission from Laser Generated Irradiated Gold Foils

    NASA Astrophysics Data System (ADS)

    Davis, Joshua; Frank, Yechiel; Raicher, Erez; Fraenkel, Moshe; Keiter, Paul; Klein, Sallee; Drake, R. P.; Shvarts, Dov

    2016-10-01

    Long pulse soft x-ray sources (SXS) allow for flexibility in high-energy-density experimental designs by providing a means of driving matter to the high temperatures needed, for example to study radiation waves in different materials. SXSs can be made by using lasers to heat a high-Z thin foil, which then acts as a quasi-blackbody emitter. Previous studies of the x-ray emission characteristics of gold foils have focused on laser pulses of 1ns or less. We performed experiments using a 6.0ns laser pulse with energy of 2kJ on the Omega-60 system to generate and characterize multi-ns laser heated Au foils of thicknesses between 0.5-2.0 μm. We measured the 2D spatial profile of the emission with a soft x-ray camera and the time history of the emission with the Dante photodiode array . Effective temperatures for the emission were then calculated using the Dante measurements. Discussion of experimental results and a comparison with 1-D Rad-Hydro NLTE simulations will be presented.

  9. Visualization of x-ray computer tomography using computer-generated holography

    NASA Astrophysics Data System (ADS)

    Daibo, Masahiro; Tayama, Norio

    1998-09-01

    The theory converted from x-ray projection data to the hologram directly by combining the computer tomography (CT) with the computer generated hologram (CGH), is proposed. The purpose of this study is to offer the theory for realizing the all- electronic and high-speed seeing through 3D visualization system, which is for the application to medical diagnosis and non- destructive testing. First, the CT is expressed using the pseudo- inverse matrix which is obtained by the singular value decomposition. CGH is expressed in the matrix style. Next, `projection to hologram conversion' (PTHC) matrix is calculated by the multiplication of phase matrix of CGH with pseudo-inverse matrix of the CT. Finally, the projection vector is converted to the hologram vector directly, by multiplication of the PTHC matrix with the projection vector. Incorporating holographic analog computation into CT reconstruction, it becomes possible that the calculation amount is drastically reduced. We demonstrate the CT cross section which is reconstituted by He-Ne laser in the 3D space from the real x-ray projection data acquired by x-ray television equipment, using our direct conversion technique.

  10. Quantitative X-ray mapping, scatter diagrams and the generation of correction maps to obtain more information about your material

    NASA Astrophysics Data System (ADS)

    Wuhrer, R.; Moran, K.

    2014-03-01

    Quantitative X-ray mapping with silicon drift detectors and multi-EDS detector systems have become an invaluable analysis technique and one of the most useful methods of X-ray microanalysis today. The time to perform an X-ray map has reduced considerably with the ability to map minor and trace elements very accurately due to the larger detector area and higher count rate detectors. Live X-ray imaging can now be performed with a significant amount of data collected in a matter of minutes. A great deal of information can be obtained from X-ray maps. This includes; elemental relationship or scatter diagram creation, elemental ratio mapping, chemical phase mapping (CPM) and quantitative X-ray maps. In obtaining quantitative x-ray maps, we are able to easily generate atomic number (Z), absorption (A), fluorescence (F), theoretical back scatter coefficient (η), and quantitative total maps from each pixel in the image. This allows us to generate an image corresponding to each factor (for each element present). These images allow the user to predict and verify where they are likely to have problems in our images, and are especially helpful to look at possible interface artefacts. The post-processing techniques to improve the quantitation of X-ray map data and the development of post processing techniques for improved characterisation are covered in this paper.

  11. A Future Generation High Angular Resolution X-ray Telescope Based Upon Physical Optics

    NASA Astrophysics Data System (ADS)

    Gorenstein, Paul

    2013-04-01

    Although the highest priority objective for the next major X-ray mission is high resolution spectroscopy we will ultimately want the next generation high angular resolution X-ray observatory. This author believes that the 0.5 arc second angular resolution of the Chandra X-Ray Observatory is likely to be close to the best that can be obtained with grazing incidence optics, especially with larger effective area. Telescopes based upon physical optics, diffraction and refraction that transmit rather than reflect X-rays can have an angular resolution of a mili arc second or better. Combining the diffractive and refractive components into one unit can neutralize the chromatic aberration of each individually over a ~15% bandwidth at 6 keV. The aperture could be divided into several diffractive-refractive pairs to broaden the bandwidth. Furthermore these telescopes would be very low cost, very light weight, and more tolerant of figure errors and surface roughness than grazing incidence telescopes. However, focal lengths are of the order of 1000 km, which requires a new mission architecture consisting of long distance formation-flying between two spacecraft, one hosting the optics, the other, the detector. One of the spacecraft requires propulsion, provided by, for example, ion engines to maintain the optics-detector alignment by counteracting gravity gradient forces, and for changing targets. Although their effective area can be large and their angular resolution very high diffractive-refractive telescopes are not necessarily more sensitive than Chandra because their large focal plane scale (1 mili arc second ~ 1 mm) subjects them to a higher level of cosmic ray background and their opacity results in a lower energy limit of 2 keV. The intrinsic field of view is wide but the large focal length scale and practical limits on the size of the detector array results in a small field of view.

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

    DOEpatents

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

    2013-06-11

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

  13. X-ray beam/biomaterial thermal interactions in third-generation synchrotron sources.

    PubMed

    Kuzay, T M; Kazmierczak, M; Hsieh, B J

    2001-01-01

    Third-generation synchrotron sources generate strong X-ray beams. The beam's interaction with biomaterials gives rise to concerns related to thermal damage and radiation damage. Of the two issues, the thermal interaction is conducive to rigorous analysis from first principles, although this has not been performed to date in a comprehensive manner. In this study, the interaction of the X-ray beam emanating from a third-generation synchrotron with a typical frozen biocrystal is theoretically studied, focusing specifically on the resulting unsteady (time-dependent) and steady heat-transfer phenomena. A unique regime map is developed to explain and to identify, on the basis of Fourier and Biot numbers as governing parameters, the applicable mathematical models that predict the subsequent thermal behavior. Depending on the values of these parameters, some simplified but realistic 'generic' solutions are generated that are suitable for that particular domain of applicability. Classical heat-transfer theory was used to describe the third-generation X-ray beam and biomaterial thermal interaction. Besides the generalized approach presented, numerous illustrative cases were solved and the resulting temperature levels are explicitly presented. Overall, the resulting thermal behavior of the system, i.e. peak and local temperature distribution, during both early transient development and for sustained long-time steady-state conditions, depends on a number of factors including the amount of energy absorbed, convective heat-transfer film coefficient and gas temperature, the sample size and shape, and the thermophysical properties of the sample and cooling gas. Results of the analysis revealed the strong influence that convection has on the transient and final steady-state temperature of the sample and the impact of internal heat conduction. The characteristic timescales of the important and dominant thermal processes with respect to the two types of thermal models are clearly

  14. Generation of phase - matched coherent point source in plasma media by propagated X-ray laser seeded beam

    NASA Astrophysics Data System (ADS)

    Pikuz, T.; Faenov, A.; Magnitskiy, S.; Nagorskiy, N.; Tanaka, M.; Ishino, M.; Nishikino, M.; Kando, M.; Kato, Y.; Kawachi, T.

    2016-03-01

    There is a significant interest in developing the coherent table-top X-ray lasers. Advent of plasma-based transient collisional excitation x-ray laser and particular, injection of coherent seeded beam, especially high-order harmonics, has tremendously improved the spatial coherence of such lasers, what allowed them to be the same widely used as synchrotron sources. Here we report experimental founding of unknown interference structure in a spatial profile of the output beam of the two-stage plasma X-ray laser. That allowed us experimental and theoretical discovering a new phenomenon consisted in a generation of phase-matched coherent point source in a laser plasma media by propagated X-ray laser seeded beam. This phenomenon could extend the applications of such x-ray lasers. For explanation of the observed phenomenon a new method of solving the standard system of Maxwell-Bloch equations has been developed. It was found that the interference pattern in the output laser beam was formed due to an emergence of phase-matched coherent virtual point source in the XRL amplifier and could be treated as the first observation of mirage phenomenon, analogous to the optical mirage, but in X-rays. The obtained results bring new comprehension into the physical nature of amplification of X-ray radiation in laser-induced plasma amplifiers and opening new opportunities for X-ray interferometry, holography and other applications, which requiring multiple rigidly phased sources of coherent radiation.

  15. Registration of 2D x-ray images to 3D MRI by generating pseudo-CT data

    NASA Astrophysics Data System (ADS)

    van der Bom, M. J.; Pluim, J. P. W.; Gounis, M. J.; van de Kraats, E. B.; Sprinkhuizen, S. M.; Timmer, J.; Homan, R.; Bartels, L. W.

    2011-02-01

    Spatial and soft tissue information provided by magnetic resonance imaging can be very valuable during image-guided procedures, where usually only real-time two-dimensional (2D) x-ray images are available. Registration of 2D x-ray images to three-dimensional (3D) magnetic resonance imaging (MRI) data, acquired prior to the procedure, can provide optimal information to guide the procedure. However, registering x-ray images to MRI data is not a trivial task because of their fundamental difference in tissue contrast. This paper presents a technique that generates pseudo-computed tomography (CT) data from multi-spectral MRI acquisitions which is sufficiently similar to real CT data to enable registration of x-ray to MRI with comparable accuracy as registration of x-ray to CT. The method is based on a k-nearest-neighbors (kNN)-regression strategy which labels voxels of MRI data with CT Hounsfield Units. The regression method uses multi-spectral MRI intensities and intensity gradients as features to discriminate between various tissue types. The efficacy of using pseudo-CT data for registration of x-ray to MRI was tested on ex vivo animal data. 2D-3D registration experiments using CT and pseudo-CT data of multiple subjects were performed with a commonly used 2D-3D registration algorithm. On average, the median target registration error for registration of two x-ray images to MRI data was approximately 1 mm larger than for x-ray to CT registration. The authors have shown that pseudo-CT data generated from multi-spectral MRI facilitate registration of MRI to x-ray images. From the experiments it could be concluded that the accuracy achieved was comparable to that of registering x-ray images to CT data.

  16. Thermonuclear ignition by Z-pinch X-ray radiation produced by current of an explosive magnetic generator

    NASA Astrophysics Data System (ADS)

    Garanin, S. G.; Ivanovskiy, A. V.

    2015-12-01

    The scheme of a device based a superpower disk-type magnetic explosion generator to produce a pulse of X-ray radiation with the energy exceeding the target ignition threshold is described and validated.

  17. Thermonuclear ignition by Z-pinch X-ray radiation produced by current of an explosive magnetic generator

    SciTech Connect

    Garanin, S. G.; Ivanovskiy, A. V.

    2015-12-15

    The scheme of a device based a superpower disk-type magnetic explosion generator to produce a pulse of X-ray radiation with the energy exceeding the target ignition threshold is described and validated.

  18. K-edge angiography utilizing a tungsten plasma X-ray generator in conjunction with gadolinium-based contrast media

    NASA Astrophysics Data System (ADS)

    Sato, Eiichi; Hayasi, Yasuomi; Tanaka, Etsuro; Mori, Hidezo; Kawai, Toshiaki; Inoue, Takashi; Ogawa, Akira; Sato, Shigehiro; Takayama, Kazuyoshi; Onagawa, Jun; Ido, Hideaki

    2006-11-01

    The tungsten plasma flash X-ray generator is useful in order to perform high-speed enhanced K-edge angiography using cone beams because K-series characteristic X-rays from the tungsten target are absorbed effectively by gadolinium-based contrast media. In the flash X-ray generator, a 150 nF condenser is charged up to 80 kV by a power supply, and flash X-rays are produced by the discharging. The X-ray tube is a demountable diode, and the turbomolecular pump evacuates air from the tube with a pressure of approximately 1 mPa. Since the electric circuit of the high-voltage pulse generator employs a cable transmission line, the high-voltage pulse generator produces twice the potential of the condenser charging voltage. At a charging voltage of 80 kV, the estimated maximum tube voltage and current were approximately 160 kV and 40 kA, respectively. When the charging voltage was increased, the characteristic X-ray intensities of tungsten K α lines increased. The K α lines were clean, and hardly any bremsstrahlung rays were detected. The X-ray pulse widths were approximately 110 ns, and the time-integrated X-ray intensity had a value of approximately 0.35 mGy at 1.0 m from the X-ray source with a charging voltage of 80 kV. Angiography was performed using a film-less computed radiography (CR) system and gadolinium-based contrast media. In angiography of non-living animals, we observed fine blood vessels of approximately 100 μm with high contrasts.

  19. Measurement of the unstained biological sample by a novel scanning electron generation X-ray microscope based on SEM.

    PubMed

    Ogura, Toshihiko

    2009-08-07

    We introduced a novel X-ray microscope system based on scanning electron microscopy using thin film, which enables the measurement of unstained biological samples without damage. An unstained yeast sample was adsorbed under a titanium (Ti)-coated silicon nitride (Si3N4) film 90 nm thick. The X-ray signal from the film was detected by an X-ray photodiode (PD) placed below the sample. With an electron beam at 2.6 kV acceleration and 6.75 nA current, the yeast image is obtained using the X-ray PD. The image is created by soft X-rays from the Ti layer. The Ti layer is effective in generating the characteristic 2.7-nm wavelength X-rays by the irradiation of electrons. Furthermore, we investigated the electron trajectory and the generation of the characteristic X-rays within the Ti-coated Si3N4 film by Monte Carlo simulation. Our system can be easily utilized to observe various unstained biological samples of cells, bacteria, and viruses.

  20. Titanium-Dioxide Nano-Fiber-Cotton Targets for Efficient Multi-keV X-Ray Generation

    SciTech Connect

    Tanabe, M; Nishimura, H; Fujioka, S; Nagai, K; Yamamoto, N; Gu, Z; Pan, C; Girard, F; Primout, M; Villette, B; Brebion, D; Fournier, K B; Fujishima, A; Mima, K

    2008-06-12

    Multi-keV x-ray generation from low-density (27 {+-} 7 mg/cc) nano-fiber-cotton targets composed of titanium-dioxide has been investigated. The cotton targets were heated volumetrically and supersonically to a peak electron temperature of 2.3 keV, which is optimal to yield Ti K-shell x rays. Considerable enhancement of conversion efficiency (3.7 {+-} 0.5%) from incident laser energy into Ti K-shell x rays (4-6 keV band) was attained in comparison with that (1.4 {+-} 0.9%) for a planar Ti-foil target.

  1. Generation of doublet spectral lines at self-seeded X-ray FELs

    NASA Astrophysics Data System (ADS)

    Geloni, Gianluca; Kocharyan, Vitali; Saldin, Evgeni

    2011-06-01

    Self-seeding schemes, consisting of two undulators with a monochromator in between, aim to reduce the bandwidth of SASE X-ray FELs. We recently proposed to use a new method of monochromatization exploiting a single crystal in Bragg transmission geometry for self-seeding in the hard X-ray range. The obvious and technically possible extension is to use such kind of monochromator setup with two (or more) crystals arranged in a series to spectrally filter the SASE radiation at two (or more) closely-spaced wavelengths within the FEL gain band. This allows for the production of doublet (or multiplet) spectral lines. Exploitations of such mode of operation involve any situation where there is a large change in cross-section over a narrow wavelength range. In this paper we consider the simultaneous operation of the LCLS hard X-ray FEL at two closely spaced wavelengths. We present simulation results for the LCLS baseline, and we show that this method can produce fully coherent radiation shared between two longitudinal modes. Mode spacing can be easily tuned within the FEL gain band, i.e. within 10 eV. An interesting aspect of the proposed scheme is a way of modulating the electron bunch at optical frequencies without a seed quantum laser. In fact, the XFEL output intensity contains an oscillating "mode-beat" component whose frequency is related to the frequency difference between the pair of longitudinal modes considered. Thus, at saturation one obtains FEL-induced modulations of energy loss and energy spread in the electron bunch at optical frequency. These modulations can be converted into density modulation at the same optical frequency with the help of a weak chicane installed behind the baseline undulator. Powerful coherent radiation can then be generated with the help of an optical transition radiation (OTR) station, which have important applications. In this paper we briefly consider how the doublet structure of the XFEL generation spectra can be monitored by an

  2. Pulse-periodic generation of supershort avalanche electron beams and X-ray emission

    NASA Astrophysics Data System (ADS)

    Baksht, E. Kh.; Burachenko, A. G.; Erofeev, M. V.; Tarasenko, V. F.

    2014-05-01

    Pulse-periodic generation of supershort avalanche electron beams (SAEBs) and X-ray emission in nitrogen, as well as the transition from a single-pulse mode to a pulse-periodic mode with a high repetition frequency, was studied experimentally. It is shown that, in the pulse-periodic mode, the full width at halfmaximum of the SAEB is larger and the decrease rate of the gap voltage is lower than those in the single-pulse mode. It is found that, when the front duration of the voltage pulse at a nitrogen pressure of 90 Torr decreases from 2.5 to 0.3 ns, the X-ray exposure dose in the pulse-periodic mode increases by more than one order of magnitude and the number of SAEB electrons also increases. It is shown that, in the pulse-periodic mode of a diffuse discharge, gas heating in the discharge gap results in a severalfold increase in the SAEB amplitude (the number of electrons in the beam). At a generator voltage of 25 kV, nitrogen pressure of 90 Torr, and pulse repetition frequency of 3.5 kHz, a runaway electron beam was detected behind the anode foil.

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

    NASA Astrophysics Data System (ADS)

    Coleman, J. E.; Welch, D. R.; Miller, C. L.

    2015-11-01

    An array of photon diagnostics has been deployed on a high power relativistic electron beam diode. Electrons are extracted through a 17.8 cm diode from the surface discharge of a carbon fiber velvet cathode with a nominal diode voltage of 3.8 MV. <10% of the 100 ns electron pulse is composed of off energy electrons (1-3 MeV) accelerated during the rise and fall of the pulse that impact the stainless steel beam pipe and generate a Bremsstrahlung spectrum of 0.1-3 MeV photons with a total count of 1011. The principal objective of these experiments is to quantify the electron beam dynamics and spatial dynamics of the hard X-ray and γ-ray flux generated in the diode region. A qualitative comparison of experimental and calculated results are presented, including time and energy resolved electron beam propagation and scattered photon measurements with X-ray PIN diodes and a photomultiplier tube indicating a dose dependence on the diode voltage >V4 and detected photon counts of nearly 106 at a radial distance of 1 m which corresponds to dose ˜40 μrad at 1 m.

  4. Scavenging of hydroxyl radicals generated in human plasma following X-ray irradiation.

    PubMed

    Hosokawa, Yoichiro; Sano, Tomoaki

    2015-11-01

    There are various antioxidant materials that scavenge free radicals in human plasma. It is possible that the radical-scavenging function causes a radiation protective effect in humans. This study estimated the hydroxyl (OH) radical-scavenging activity induced by X-ray irradiation in human plasma. The test subjects included 111 volunteers (75 males and 36 females) ranging from 22 to 35 years old (average, 24.0). OH radicals generated in irradiated human plasma were measured by electron spin resonance (ESR). The relationships between the amount of the OH radical and chemical and biological parameters [total protein, total cholesterol, triglycerides and hepatitis B surface (HBs) antibodies] were estimated in the plasma of the 111 volunteers by a multivariate analysis. The presence of HBs antibodies had the greatest influence on OH radical-scavenging activity. One volunteer who did not have the HBs antibody was given an inoculation of the hepatitis B vaccine. There was a remarkable decrease in the amount of OH radical generated from plasma after the HBs antibody was produced. The results indicate that the HBs antibody is an important factor for the scavenging of OH radicals initiated by X-ray irradiation in the human body.

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

    SciTech Connect

    Coleman, J. E.; Welch, D. R.; Miller, C. L.

    2015-11-14

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

  6. X-ray generation mechanisms in three-dimensional simulations of wire array Z-pinches

    NASA Astrophysics Data System (ADS)

    Chittenden, J. P.; Lebedev, S. V.; Jennings, C. A.; Bland, S. N.; Ciardi, A.

    2004-12-01

    Resistive magneto-hydrodynamic (MHD) simulations are used to evaluate the influence of three-dimensional inhomogeneities on x-ray power production in wire array Z-pinches. In particular, we concentrate on simulations of wire array Z-pinch experiments on the MAGPIE generator at Imperial College. An initial temperature perturbation is used to stimulate variations in wire core ablation rates that result in a highly non-uniform final implosion. Results indicate that x-ray power production is governed by the symmetry of the implosion surface and by the rate at which current can transfer to the axis through a three-dimensional debris field that trails behind the main implosion. The peak power is ultimately limited by the growth of MHD instabilities in the stagnated pinch. The individual contributions of the implosion kinetic energy, compression of the stagnated pinch, ohmic heating and MHD instabilities to the radiation yield are quantified. The onset of m = 1 instabilities is found to provide an efficient mechanism for dissipation of the magnetic energy surrounding the stagnated pinch. The formation of a helical plasma column not only allows the magnetic field to do work in driving an expansion of the helix but also enhances the ohmic heating by elongating the path of the current through the pinch. The effect of these energy sources combined is to increase the radiation yield to typically 3½ times the kinetic energy of the implosion. Simulations of arrays with different wire numbers, wire material and with nested arrays are used to examine the mechanisms that influence the peak soft x-ray power. In the simulations, peak power can be increased by: increasing the number of wires (which improves the implosion symmetry), by increasing the atomic number of the material (which increases the compressibility of the plasma) and by using a nested inner array (which brings the mass and the current to the axis more efficiently than a single array).

  7. Investigation of gas generation in regenerative fuel cells by low-energy X-rays

    NASA Astrophysics Data System (ADS)

    Selamet, Omer Faruk; Deevanhxay, Phengxay; Tsushima, Shohji; Hirai, Shuichiro

    2015-11-01

    Gas generation and discharge behaviors in an operating regenerative fuel cell (RFC) are investigated using low-energy X-ray radiography. In situ visualization at high spatial and temporal resolution reveal dynamic and inhomogeneous behaviors of the gas generation in the membrane electrode assembly (MEA) in the RFC. Temporal and spatial variation of the gas thickness in the MEA is quantitatively discussed and shows an intermittent and periodic discharge processes of the gas generated by electrolysis, suggesting that the reaction sites in the catalyst layer and the discharging path of gas bubbles are well established in the MEA for the electrolysis. Larger gas accumulation and discharge in the gas diffusion layer (GDL) under the ribs are identified in comparison with those under the channels, which is attributed to the relatively longer path for accumulated gas under the ribs to be discharged into the flow channels.

  8. [Analysis of the 4th generation outer space bred Angelica dahurica by FTIR spectroscopy].

    PubMed

    Zhu, Yan-ying; Wu, Peng-le; Liu, Mei-yi; Wang, Zhi-zhou; Guo, Xi-hua; Guan, Ying

    2012-03-01

    The major components of the 4th generation outer space bred angelica and the ground group were determined and analyzed by Fourier transform infrared spectroscopy (FTIR) and second derivative spectrum, considering the large mutation of the plants with space mutagenesis. The results show that the content of the coumarin (1741 cm(-1)), which is the main active components of the space angelica dahurica increased, and the content of the protein (1 459, 1 419 cm(-1)) and the fat (930 cm(-1)) increased slightly, whereas the content of the starch and the dietary fiber reduced drastically. There are obvious differences between the peak values of the second derivative spectra of the plants, revealing that the outer space angelica dahurica contained amine component at 1 279 cm(-1). Space mutation breeding is favor of breeding angelica with better idiosyncrasy.

  9. 4th generation of the 1st level surface detector trigger in the Pierre Auger Observator

    NASA Astrophysics Data System (ADS)

    Szadkowski, Z.

    The proposal of a new 4th generation of the Front-End with the advanced 1st level triggers for the Infill Array of the Pierre Auger Observatory and for the Auger North is described. Newest FPGA chips offer much higher capacity of logic registers and memories, as well as DSP blocks. The calibration channel, previously supported by an external dual-port RAM, has been fully implemented into FPGA chip, through a large internal memory. In turn DSP blocks allowed on implementation of much more sophisticated spectral trigger algorithms. A single chip simplified board design, newer architecture of FPGA reduced resouces utilization and power consumption. Higher sampling in the new Front- End in comparison with previous 40 MHz designs as well as free resources for new detection algotithms can be a good platform for CR radio detection technique at Auger enhancing a duty cycle for the detection of UHECR’s.

  10. Moving-Article X-Ray Imaging System and Method for 3-D Image Generation

    NASA Technical Reports Server (NTRS)

    Fernandez, Kenneth R. (Inventor)

    2012-01-01

    An x-ray imaging system and method for a moving article are provided for an article moved along a linear direction of travel while the article is exposed to non-overlapping x-ray beams. A plurality of parallel linear sensor arrays are disposed in the x-ray beams after they pass through the article. More specifically, a first half of the plurality are disposed in a first of the x-ray beams while a second half of the plurality are disposed in a second of the x-ray beams. Each of the parallel linear sensor arrays is oriented perpendicular to the linear direction of travel. Each of the parallel linear sensor arrays in the first half is matched to a corresponding one of the parallel linear sensor arrays in the second half in terms of an angular position in the first of the x-ray beams and the second of the x-ray beams, respectively.

  11. X-ray production and second-harmonic generation during femtosecond laser microdrilling

    NASA Astrophysics Data System (ADS)

    Gordienko, V. M.; Zhvaniya, I. A.; Makarov, I. A.

    2015-08-01

    We investigated X-ray yield and second-harmonic generation during femtosecond laser drilling of solid targets placed in vacuum or air. Laser pulse intensity was about 1016 W/cm2 and repetition rate was 10 Hz. Hard X-ray yield ( E > 2.5 keV) and second-harmonic signal are non-monotone and reach a maximum during formation of microchannel in a target. That indicates that both signals can be utilized as a feedback for monitoring laser energy deposition to the target under laser microdrilling. Spectrum of second harmonic emitted from laser-drilled microchannel is blueshifted regardless of target type or environment (vacuum or air surrounding the target). The blueshift reaches the value of about 30 nm. The spectrum of fundamental radiation backreflected from the microchannel has also corresponding blueshift. This testifies that the cloud of ablated particles accumulates inside the microchannel. Incident laser radiation undergoes self-action inside the cloud, as a result occurs the spectral modification of incident radiation and its second harmonic.

  12. Flexible Field Emitter for X-ray Generation by Implanting CNTs into Nickel Foil.

    PubMed

    Sun, Bin; Wang, Yan; Ding, Guifu

    2016-12-01

    This paper reports a novel implanting micromachining technology. By using this method, for the first time, we could implant nano-scale materials into milli-scale metal substrates at room temperature. Ni-based flexible carbon nanotube (CNT) field emitters were fabricated by the novel micromachining method. By embedding CNT roots into Ni foil using polymer matrix as transfer media, effective direct contact between Ni and CNTs was achieved. As a result, our novel emitter shows relatively good field emission properties such as low turn-on field and good stability. Moreover, the emitter was highly flexible with preservation of the field emission properties. The excellent field emission characteristics attributed to the direct contact and the strong interactions between CNTs and the substrate. To check the practical application of the novel emitter, a simple X-ray imaging system was set up by modifying a traditional tube. The gray shadow that appears on the sensitive film after being exposed to the radiation confirms the successful generation of X-ray.

  13. Flexible Field Emitter for X-ray Generation by Implanting CNTs into Nickel Foil

    NASA Astrophysics Data System (ADS)

    Sun, Bin; Wang, Yan; Ding, Guifu

    2016-07-01

    This paper reports a novel implanting micromachining technology. By using this method, for the first time, we could implant nano-scale materials into milli-scale metal substrates at room temperature. Ni-based flexible carbon nanotube (CNT) field emitters were fabricated by the novel micromachining method. By embedding CNT roots into Ni foil using polymer matrix as transfer media, effective direct contact between Ni and CNTs was achieved. As a result, our novel emitter shows relatively good field emission properties such as low turn-on field and good stability. Moreover, the emitter was highly flexible with preservation of the field emission properties. The excellent field emission characteristics attributed to the direct contact and the strong interactions between CNTs and the substrate. To check the practical application of the novel emitter, a simple X-ray imaging system was set up by modifying a traditional tube. The gray shadow that appears on the sensitive film after being exposed to the radiation confirms the successful generation of X-ray.

  14. X-ray radiation from puff-on-wire implosion on the COBRA generator

    NASA Astrophysics Data System (ADS)

    Ouart, N.; Engelbrecht, J.; de Grouchy, P.; Qi, N.; Shelkovenko, T.; Pikuz, S.; Kusse, B.; Hammer, D.; Giuliani, J.; Dasgupta, A.; Velikovich, A.; Apruzese, J.; Clark, R.

    2016-10-01

    Substantial progress has been made in developing plasma radiation sources from Z-pinch implosions. University pulsed power machines provide a cost effective platform to study alternative mechanisms of producing x-rays that may provide guidance in search of further improvements on the larger machines. Radiation from puff-on-wire implosions were previously studied. We report recent observations and modeling of puff-on-wire implosions using the 1 MA COBRA generator in the long pulse mode. The gas puff used Ne, Ar, or Kr and the wire material was either Cu or manganin 290 (84% Cu, 12% Mn, 4% Ni). The diagnostics include time-integrated pinhole cameras and an axially resolved spectrometer, multiple filtered PCDs and Si-diodes, and time-gated XUV cameras. X-ray radiation from the gas puff and the K-alpha line from wire material was detected. A 1-D multi-zone non-LTE kinetics code with radiation transport will be used to model the radiation to infer the plasma conditions. Work supported by DOE/NNSA.

  15. Constraining high-redshift X-ray sources with next generation 21-cm power spectrum measurements

    NASA Astrophysics Data System (ADS)

    Ewall-Wice, Aaron; Hewitt, Jacqueline; Mesinger, Andrei; Dillon, Joshua S.; Liu, Adrian; Pober, Jonathan

    2016-05-01

    We use the Fisher matrix formalism and seminumerical 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 25, we find that the proposed 331 element HERA and SKA phase 1 will be capable of placing ≲ 10 per cent 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 heating and reionization physics lead to errors on reionization parameters that are significantly greater than previously predicted. Observations over the heating epoch are able to break these degeneracies and improve our constraints considerably. For these two reasons, 21-cm observations during the heating epoch significantly enhance our understanding of reionization as well.

  16. THE NEXT GENERATION ATLAS OF QUASAR SPECTRAL ENERGY DISTRIBUTIONS FROM RADIO TO X-RAYS

    SciTech Connect

    Shang Zhaohui; Li Jun; Xie Yanxia; Brotherton, Michael S.; Cales, Sabrina L.; Dale, Daniel A.; Runnoe, Jessie C.; Kelly, Benjamin J.; Wills, Beverley J.; Wills, D.; Green, Richard F.; Nemmen, Rodrigo S.; Ganguly, Rajib; Hines, Dean C.; Kriss, Gerard A.; Tang, Baitian

    2011-09-01

    We have produced the next generation of quasar spectral energy distributions (SEDs), essentially updating the work of Elvis et al. by using high-quality data obtained with several space- and ground-based telescopes, including NASA's Great Observatories. We present an atlas of SEDs of 85 optically bright, non-blazar quasars over the electromagnetic spectrum from radio to X-rays. The heterogeneous sample includes 27 radio-quiet and 58 radio-loud quasars. Most objects have quasi-simultaneous ultraviolet-optical spectroscopic data, supplemented with some far-ultraviolet spectra, and more than half also have Spitzer mid-infrared Infrared Spectrograph spectra. The X-ray spectral parameters are collected from the literature where available. The radio, far-infrared, and near-infrared photometric data are also obtained from either the literature or new observations. We construct composite SEDs for radio-loud and radio-quiet objects and compare these to those of Elvis et al., finding that ours have similar overall shapes, but our improved spectral resolution reveals more detailed features, especially in the mid- and near-infrared.

  17. A bright attosecond x-ray pulse train generation in a double-laser-driven cone target

    NASA Astrophysics Data System (ADS)

    Hu, Li-Xiang; Yu, Tong-Pu; Shao, Fu-Qiu; Luo, Wen; Yin, Yan

    2016-06-01

    By using full three-dimensional particle-in-cell and Monte Carlo simulations, we investigate the generation of a high-brightness attosecond x-ray pulse train in a double-laser-driven cone target. The scheme makes use of two lasers: the first high-intensity laser with a laser peak intensity 1.37 × 1020 W/cm2 irradiates the cone and produces overdense attosecond electron bunches; the second counterpropagating weakly relativistic laser with a laser peak intensity 4.932 × 1017 W/cm2 interacts with the produced electron bunches and a bright x-ray pulse train is generated by Thomson backscattering of the second laser off the attosecond electron bunches. It is shown that the photon flux rises by 5 times using the cone target as compared with a normal channel. Meanwhile, the x-ray peak brightness increases significantly from 1.4 × 1021/(s mm2 mrad2 0.1 keV) to 6.0 × 1021/(s mm2 mrad2 0.1 keV), which is much higher than that of the Thomson x-ray source generated from traditional accelerators. We also discuss the influence of the laser and target parameters on the x-ray pulse properties. This compact bright x-ray source may have diverse applications, e.g., the study of electric dynamics and harmonics emission in the atomic scale.

  18. Generation-X mirror technology development plan and the development of adjustable x-ray optics

    NASA Astrophysics Data System (ADS)

    Reid, Paul B.; Davis, William; O'Dell, Stephen; Schwartz, Daniel A.; Tolier-McKinstry, Susan; Wilke, Rudeger H. T.; Zhang, William

    2009-08-01

    Generation-X is being studied as an extremely high resolution, very large area grazing incidence x-ray telescope. Under a NASA Advanced Mission Concepts Study, we have developed a technology plan designed to lead to the 0.1 arcsec (HPD) resolution adjustable optics with 50 square meters of effective area necessary to meet Generation-X requirements. We describe our plan in detail. In addition, we report on our development activities of adjustable grazing incidence optics via the fabrication of bimorph mirrors. We have successfully deposited thin-film piezo-electric material on the back surface of thin glass mirrors. We report on the electrical and mechanical properties of the bimorph mirrors. We also report on initial finite element modeling of adjustable grazing incidence mirrors; in particular, we examine the impact of how the mirrors are supported - the boundary conditions - on the deformations which can be achieved.

  19. Evidence of High Harmonics from Echo-Enabled Harmonic Generation for Seeding X-ray Free Electron Lasers

    SciTech Connect

    Xiang, D.; Colby, E.; Dunning, M.; Gilevich, S.; Hast, C.; Jobe, K.; McCormick, D.; Nelson, J.; Raubenheimer, T.O.; Soong, K.; Stupakov, G.; Szalata, Z.; Walz, D.; Weathersby, S.; Woodle, M.; /SLAC

    2012-02-15

    Echo-enabled harmonic generation free electron lasers hold great promise for the generation of fully coherent radiation in x-ray wavelengths. Here we report the first evidence of high harmonics from the echo-enabled harmonic generation technique in the realistic scenario where the laser energy modulation is comparable to the beam slice energy spread. In this experiment, coherent radiation at the seventh harmonic of the second seed laser is generated when the energy modulation amplitude is about 2-3 times the slice energy spread. The experiment confirms the underlying physics of echo-enabled harmonic generation and may have a strong impact on emerging seeded x-ray free electron lasers that are capable of generating laserlike x rays which will advance many areas of science.

  20. Next Generation Astronomical X-ray Optics: High Angular Resolution, Light Weight, and Low Production Cost

    NASA Technical Reports Server (NTRS)

    Zhang. W. W.; Biskach, M. P.; Blake, P. N.; Chan, K. W.; Gaskin, J. A.; Hong, M. L.; Jones, W. D.; Kolos, L. D.; Mazzarella, J. R.; McClelland, R. S.; O'Dell, S. L.; Saha, T. T.; Sharpe, M. V.

    2012-01-01

    X-ray astronomy depends on the availability of telescopes with high resolution and large photon collecting areas. Since x-ray observation can only be carried out above the atmosphere, these telescopes must be necessarily lightweight. Compounding the lightweight requirement is that an x-ray telescope consists of many nested concentric shells, which further require that x-ray mirrors must also be geometrically thin to achieve high packing efficiency. This double lightweight and geometrically thin requirement poses significant technical challenges in fabricating the mirrors and in integrating them into mirror assemblies. This paper reports on the approach, strategy and status of our x-ray optics development program whose objective is to meet these technical challenges at modest cost to enable future x-ray missions, including small Explorer missions in the near term, probe class missions in the medium term, and large flagship missions in the long term.

  1. A triboelectric closed loop band system for the generation of x-rays

    NASA Astrophysics Data System (ADS)

    Van Cleve, E.; Lucas, B.; Ganlieli, Z.; Wong, E. W.; Cortes, P.; Mehta, N.; Cuadra, D.; Fong, J.; Hansen, S.; Kotowski, A.; Camara, C. G.

    2015-08-01

    X-ray have been commercially produced using the same basic design since their discovery by Wilhelm Roentgen in 1895, for which he was awarded the first Nobel prize in physics. This technology requires high voltage elements, ultra high vacuum tubes, and high voltage electronics. The vacuum and high voltage drive up the price of x-ray technology and in order to bring down the cost, a brand new way to produce x-rays is needed. In 2008 Carlos Camara, Juan Escobar, Jonathan R. Hird, and Seth Putterman1 discovered that by pealing scotch tape in a vacuum you could create enough x-rays to take an x-ray radiograph of a finger. This lead to the formation of Tribogenics and the development of the rod and band x-ray architecture.

  2. The X-ray properties of normal galaxies. What do we know and what can we learn with the next generation of X-ray telescopes?. [spaceborne telescope

    NASA Technical Reports Server (NTRS)

    Fabbiano, G.

    1985-01-01

    Einstein Observatory results are used to assess the possibilities of spaceborne X-ray astronomy projects such as XMM (ESA) and AXAF (NASA). Einstein observations show that normal galaxies of all morphological types are spatially extended sources of X-ray emission with 0.5 to 3.0 keV X-ray luminosities of 10 to the 39th to 41st power erg/sec. X-ray telescopes can study the end products of stellar evolution in galaxies of different morphological types. Phenomena linked to starburst nuclear activity can best be detected and studied in X-ray. Hot coronae or a hot phase of the interstellar medium can only be studied through their X-ray emission. It is shown that high spatial resolution is essential for studying normal galaxies and identifying different emission regions. Good spectral sensitivity and spectral imaging capability are essential for gaining a deeper understanding of the phenomena at work.

  3. Requirements for use of nonmedical x-ray generators at SLAC

    SciTech Connect

    Busick, D.D.

    1984-09-01

    The risks associated with use of x-ray equipment have long been recognized. While the relative frequency of x-ray damage is small, machine produced x-rays and large radiography sources continue to account for a large percentage of preventable radiation injuries reported worldwide. The intent of this report is to formalize SLAC's radiation safety program as it applies to radiation producing equipment (diffraction, fluorescence analysis and nondestructive testing). It does not apply to the two-mile linac, experimental areas or other x-ray producing equipment directly related to the high energy physics program. 4 refs., 3 figs., 1 tab.

  4. Generation of strongly coupled Xe cluster nanoplasmas by low intensive soft x-ray laser irradiation

    SciTech Connect

    Namba, S.; Hasegawa, N.; Kishimoto, M.; Nishikino, M.; Kawachi, T.

    2012-07-11

    A seeding gas jet including Xe clusters was irradiated with a laser-driven plasma soft x-ray laser pulse ({lambda}=13.9 nm, {approx}7 ps, {<=}5 Multiplication-Sign 10{sup 9} W/cm{sup 2}), where the laser photon energy is high enough to ionize 4d core electrons. In order to clarify how the innershell ionization followed by the Auger electron emission is affected under the intense laser irradiation, the electron energy distribution was measured. Photoelectron spectra showed that the peak position attributed to 4d hole shifted to lower energy and the spectral width was broadened with increasing cluster size. Moreover, the energy distribution exhibited that a strongly coupled cluster nanoplasma with several eV was generated.

  5. Intense high repetition rate Mo Kα x-ray source generated from laser solid interaction for imaging application

    SciTech Connect

    Huang, K.; Li, M. H.; Yan, W. C.; Ma, Y.; Zhao, J. R.; Li, Y. F.; Chen, L. M.; Guo, X.; Li, D. Z.; Chen, Y. P.; Zhang, J.

    2014-11-15

    We report an efficient Mo Kα x-ray source produced by interaction of femtosecond Ti: sapphire laser pulses with a solid Molybdenum target working at 1 kHz repetition rate. The generated Mo Kα x-ray intensity reaches to 4.7 × 10{sup 10} photons sr{sup −1} s{sup −1}, corresponding to an average power of 0.8 mW into 2π solid angle. The spatial resolution of this x-ray source is measured to be 26 lp/mm. With the high flux and high spatial resolution characteristics, high resolving in-line x-ray radiography was realized on test objects and large size biological samples within merely half a minute. This experiment shows the possibility of laser plasma hard x-ray source as a new low cost and high resolution system for radiography and its ability of ultrafast x-ray pump-probe study of matter.

  6. Real-time observation of coherent acoustic phonons generated by an acoustically mismatched optoacoustic transducer using x-ray diffraction

    SciTech Connect

    Persson, A. I. H.; Andreasson, B. P.; Enquist, H.; Jurgilaitis, A.; Larsson, J.

    2015-11-14

    The spectrum of laser-generated acoustic phonons in indium antimonide coated with a thin nickel film has been studied using time-resolved x-ray diffraction. Strain pulses that can be considered to be built up from coherent phonons were generated in the nickel film by absorption of short laser pulses. Acoustic reflections at the Ni–InSb interface leads to interference that strongly modifies the resulting phonon spectrum. The study was performed with high momentum transfer resolution together with high time resolution. This was achieved by using a third-generation synchrotron radiation source that provided a high-brightness beam and an ultrafast x-ray streak camera to obtain a temporal resolution of 10 ps. We also carried out simulations, using commercial finite element software packages and on-line dynamic diffraction tools. Using these tools, it is possible to calculate the time-resolved x-ray reflectivity from these complicated strain shapes. The acoustic pulses have a peak strain amplitude close to 1%, and we investigated the possibility to use this device as an x-ray switch. At a bright source optimized for hard x-ray generation, the low reflectivity may be an acceptable trade-off to obtain a pulse duration that is more than an order of magnitude shorter.

  7. Studies of the Origin of High-frequency Quasi-periodic Oscillations of Mass-accreting Black Holes in X-Ray Binaries with Next-generation X-Ray Telescopes

    NASA Astrophysics Data System (ADS)

    Beheshtipour, Banafsheh; Hoormann, Janie K.; Krawczynski, Henric

    2016-08-01

    Observations with RXTE (Rossi X-ray Timing Explorer) revealed the presence of high-frequency quasi-periodic oscillations (HFQPOs) of the X-ray flux from several accreting stellar-mass black holes. HFQPOs (and their counterparts at lower frequencies) may allow us to study general relativity in the regime of strong gravity. However, the observational evidence today does not yet allow us to distinguish between different HFQPO models. In this paper we use a general-relativistic ray-tracing code to investigate X-ray timing spectroscopy and polarization properties of HFQPOs in the orbiting Hotspot model. We study observational signatures for the particular case of the 166 Hz quasi-periodic oscillation (QPO) in the galactic binary GRS 1915+105. We conclude with a discussion of the observability of spectral signatures with a timing-spectroscopy experiment such as the LOFT (Large Observatory for X-ray Timing) and polarization signatures with space-borne X-ray polarimeters such as IXPE (Imaging X-ray Polarimetry Explorer), PolSTAR (Polarization Spectroscopic Telescope Array), PRAXyS(Polarimetry of Relativistic X-ray Sources), or XIPE (X-ray Imaging Polarimetry Explorer). A mission with high count rate such as LOFT would make it possible to get a QPO phase for each photon, enabling the study of the QPO-phase-resolved spectral shape and the correlation between this and the flux level. Owing to the short periods of the HFQPOs, first-generation X-ray polarimeters would not be able to assign a QPO phase to each photon. The study of QPO-phase-resolved polarization energy spectra would thus require simultaneous observations with a first-generation X-ray polarimeter and a LOFT-type mission.

  8. Detection of a Cool, Accretion-Shock-Generated X-Ray Plasma in EX Lupi During the 2008 Optical Eruption

    NASA Technical Reports Server (NTRS)

    Teets, William K.; Weintraub, David A.; Kastner, Joel H.; Grosso, Nicholas; Hamaguchi, Kenji; Richmond, Michael

    2012-01-01

    EX Lupi is the prototype for a class of young, pre-main-sequence stars which are observed to undergo irregular, presumably accretion-generated, optical outbursts that result in a several magnitude rise of the optical flux. EX Lupi was observed to optically erupt in 2008 January, triggering Chandra ACIS Target of Opportunity observations shortly thereafter. We find very strong evidence that most of the X-ray emission in the first few months after the optical outburst is generated by accretion of circumstellar material onto the stellar photosphere. Specifically, we find a strong correlation between the decreasing optical and X-ray fluxes following the peak of the outburst in the optical, which suggests that these observed declines in both the optical and X-ray fluxes are the result of declining accretion rate. In addition, in our models of the X-ray spectrum, we find strong evidence for an approx 0.4 keV plasma component, as expected for accretion shocks on low-mass, pre-main-sequence stars. From 2008 March through October, this cool plasma component appeared to fade as EX Lupi returned to its quiescent level in the optical, consistent with a decrease in the overall emission measure of accretion-shock-generated plasma. The overall small increase of the X-ray flux during the optical outburst of EX Lupi is similar to what was observed in previous X-ray observations of the 2005 optical outburst of the EX Lupi-type star V1118 Ori but contrasts with the large increase of the X-ray flux from the erupting young star V1647 Ori during its 2003 and 2008 optical outbursts.

  9. High-gain harmonic generation of soft X-rays with the `fresh bunch` technique

    SciTech Connect

    Yu, Li-Hua; Ben-Zvi, I.

    1996-10-01

    We report numerical simulations (using the TDA code) and analytic verification of the generation of 64 {Angstrom} high power soft X- rays from an exponential regime single pass seeded FEL. The seed is generated in the FEL using the High Gain Harmonic Generation (HGHG) technique combined with the `Fresh bunch` technique. A seed pulse at 2944 {Angstrom} is generated by conventional laser techniques. The seed pulse produces an intense energy modulation of the rear part of a I GeV, 1245 {Angstrom} electron beam in a `modulator` wiggler. In the `radiator` wiggler, (resonant to 64 {Angstrom}), the energy modulation creates beam density modulation followed by radiation of the 46{sup th} harmonic of the seed. We use a magnetic delay to position the 64 A{Angstrom} radiation at the undisturbed front of the bunch to serve as a seed for a single pass, exponential growth FEL. After a 9 m long exponential section followed by a 7 m long tapered section the radiation power reaches 3.3 GW.

  10. Beam characterization of a lab bench cold cathode ultra-soft X-ray generator

    NASA Astrophysics Data System (ADS)

    Ounoughi, N.; Mavon, C.; Belafrites, A.; Groetz, J.-E.; Fromm, M.

    2013-06-01

    The aim of this work is to characterize the Ultra Soft X-ray (USX, 1.5 keV, Al Kα) photon beam of a customized lab bench cold cathode generator. Within this generator, the electron beam is slowed down in a thin aluminium foil (16 μm) supported by an easily exchangeable anode. It is shown that the thickness of the foil and the anode configuration determine the spatial distribution and the fluence rate of the photon beam, whereas accelerating voltage determines both fluence rate and energy spectrum feature. It is shown also that under specific operation parameters (i.e. accelerating voltage), a Gaussian energy distribution of the beam can be generated which is centred on the energy of the Al Kα line (1.5 keV). Dosimetric films of GAFCHROMIC® HD-810 were used to estimate the photon fluence rate distribution of the beam. Its variation, when the generator acts as a monoenergetic source, was characterized with the two different configurations of the anode assembly. Finally, it is verified that the anode assembly consisting in a flat washer, on which the aluminium foil is set, acts as a simple point-source.

  11. Characteristics of a high-intensity plasma flash x-ray generator having a double-target radiation tube

    NASA Astrophysics Data System (ADS)

    Sato, Eiichi; Sagae, Michiaki; Takahashi, Kei; Oizumi, Teiji; Hayasi, Yasuomi; Tamakawa, Yoshiharu; Yanagisawa, Toru

    1995-05-01

    The radiographic characteristics of a high-intensity plasma flash x-ray generator having a solid-target (anode) radiation tube are described. This generator consisted of the following essential components; a high- voltage power supply, a low-impedance coaxial transmission line, a coaxial oil condenser of 0.2 (mu) F, a turbo-molecular pump, a thyratron pulser as a trigger device, and a flash x-ray triode having a rod-shaped long double anode; a 2.0 mm inner tungsten anode was embedded in 3.0 mm copper anode. The high-voltage condenser was charged from 40 to 60 kV by the power supply, and the electric charges in the condenser were discharged to the tube after triggering the cathode electrode. The maximum tube voltage was equivalent to the charged voltage of the main condenser, and the voltage decreased after the triggering. Both the tube voltage and the current displayed damped oscillations, and the maximum tube current was less than 20 kA. The pulse height of the flash x rays substantially increased according to increases in the charged voltage, and the x-ray durations had values of a few microseconds. The plasma x- ray source substantially grew when the charged voltage was increased. The flash x-ray spectra from the plasma x-ray source were measured by a transmission-type spectrometer having a LiF curved crystal of 0.5 mm in thickness. Compared to the intensities of copper K(alpha) 1 and K(alpha) 2 including nondiagram lines increased by using the double target.

  12. Conditions for the generation of cytotoxic CD4+ Th cells that enhance CD8+ CTL-mediated tumor regression

    PubMed Central

    Li, Kunyu; Baird, Margaret; Yang, Jianping; Jackson, Chris; Ronchese, Franca; Young, Sarah

    2016-01-01

    Adoptive cell therapies (ACTs) using tumor-reactive T cells have shown clinical benefit and potential for cancer treatment. While the majority of the current ACT are focused on using CD8+ cytotoxic T lymphocytes (CTL), others have shown that the presence of tumor-reactive CD4+ T helper (Th) cells can greatly enhance the anti-tumor activity of CD8+ CTL. However, difficulties in obtaining adequate numbers of CD4+ Th cells through in vitro expansion can limit the application of CD4 Th cells in ACT. This study aims to optimize the culture conditions for mouse CD4 T cells to provide basic information for animal studies of ACT using CD4 T cells. Taking advantage of the antigen-specificity of CD4+ Th cells from OT-II transgenic mice, we examined different methodologies for generating antigen-specific CD4+ Th1 cells in vitro. We found that cells grown in complete advanced-DMEM/F12 medium supplemented with low-dose IL-2 and IL-7 induced substantial cell expansion. These Th cells were Th1-like, as they expressed multiple Th1-cytokines and exhibited antigen-specific cytotoxicity. In addition co-transfer of these CD4+ Th1-like cells with CD8+ CTL significantly enhanced tumor regression, leading to complete cure in 80% of mice bearing established B16-OVA. These observations indicate that the CD4+ Th1-like cells generated using the method we optimized are functionally active to eliminate their target cells, and can also assist CD8+ CTL to enhance tumor regression. The findings of this study provide valuable data for further research into in vitro expansion of CD4+ Th1-like cells, with potential applications to cancer treatment involving ACT. PMID:27588200

  13. Three-dimensional time and frequency-domain theory of femtosecond x-ray pulse generation through Thomson Scattering

    SciTech Connect

    Brown, W J; Hartemann, F V

    2004-01-27

    The generation of high intensity, ultra-short x-ray pulses enables exciting new experimental capabilities, such as femtosecond pump-probe experiments used to temporally resolve material structural dynamics on atomic time scales. Thomson backscattering of a high intensity laser pulse with a bright relativistic electron bunch is a promising method for producing such high brightness x-ray pulses in the 10-100 keV range within a compact facility. While a variety of methods for producing sub-picosecond x-ray bursts by Thomson scattering exist, including compression of the electron bunch to sub-picosecond bunch lengths and/or colliding a sub-picosecond laser pulse in a side-on geometry to minimize the interaction time, a promising alternative approach to achieving this goal while maintaining ultra-high brightness is the production of a time correlated (or chirped) x-ray pulse in conjunction with pulse slicing or compression. We present the results of a complete analysis of this process using a recently developed 3-D time and frequency-domain code for analyzing the spatial, temporal, and spectral properties an x-ray beam produced by relativistic Thomson scattering. Based on the relativistic differential cross section, this code has the capability to calculate time and space dependent spectra of the x-ray photons produced from linear Thomson scattering for both bandwidth-limited and chirped incident laser pulses. Spectral broadening of the scattered x-ray pulse resulting from the incident laser bandwidth, laser focus, and the transverse and longitudinal phase space of the electron beam were examined. Simulations of chirped x-ray pulse production using both a chirped electron beam and a chirped laser pulse are presented. Required electron beam and laser parameters are summarized by investigating the effects of beam emittance, energy spread, and laser bandwidth on the scattered x-ray spectrum. It is shown that sufficient temporal correlation in the scattered x-ray spectrum

  14. Design of a carbon-nanotube yarn field emitter for micro-focus X-ray generation

    NASA Astrophysics Data System (ADS)

    Kim, Hyun Suk; Castro, Edward Joseph D.; Lee, Choong Hun

    2016-08-01

    The field-emission (F-E) characteristics of multi-walled carbon-nanotube (MWCNT) yarn and its contribution to X-ray generation have been investigated in the current work. A dry spinning method was used to fabricateMWCNT yarn from superMWCNTs that had been fabricated by using microwave plasma-enhanced chemical vapor deposition (MW-PECVD). The F-E behavior of the MWCNT yarn followed the Fowler-Nordheim model. Compared to a MWCNT, the MWCNT yarn displayed a significant F-E capability in both the diode and the triode X-ray generation structures. The low-voltage F-E of the MWCNT yarn can be attributed to the field-enhancing effect of the yarn due to its shape and to the contribution of the high-aspect-ratio nanotubes that protrude from the sides of the yarn. The effect of filters on the development of X-ray images has also been demonstrated. The amount of exposure of the samples to X-rays was also manipulated. Results of this study indicate that the MWCNT yarn may be a good candidate for use in low-voltage F-E applications for X-ray imaging.

  15. IQ Aur: A new mode of X-ray generation in magnetic stars ?

    NASA Astrophysics Data System (ADS)

    Schmitt, Jurgen

    2007-10-01

    We propose to obtain the first high-resolution X-ray spectrum of the peculiar magnetic A-type star IQ Aur. From previous X-ray observations IQ Aur is known as a strong (LX ~ 4 10**29 erg/s), but very soft (TX ~ 0.29 keV) X-ray source. An attribution of IQ~Aur's X-ray emission to a low-mass companion would imply totally unusual properties of such an hypothesized object, thus IQ Aur is a good candidate for an A-type star with intrinsic X-ray emission.The XMM-Newton RGS spectrum will constrain the location of the X-ray emission site from a measurement or upper limit to the strength of the OVII f line, the overall RGS spectrum will determine the elemental abundances, which may be far away from solar,and the phase coverage will allow a search for rotational modulation of IQ Aur's X-ray flux.

  16. Generating femtosecond X-ray pulses using an emittance-spoiling foil in free-electron lasers

    SciTech Connect

    Ding, Y. Coffee, R.; Decker, F.-J.; Emma, P.; Field, C.; Huang, Z.; Krejcik, P.; Krzywinski, J.; Loos, H.; Lutman, A.; Marinelli, A.; Maxwell, T. J.; Turner, J.; Behrens, C.; Helml, W.

    2015-11-09

    Generation of femtosecond to sub-femtosecond pulses is attracting much attention in X-ray free-electron laser user community. One method is to use a slotted, emittance-spoiling foil which was proposed before (P. Emma et al., Phys. Rev. Lett. 92, 074801 (2004)) and has been widely used at the Linac Coherent Light Source. Direct experimental characterization of the slotted-foil performance was previously unfeasible due to a lack of appropriate diagnostics. With a recently installed X-band radio-frequency transverse deflector, we are able to characterize the electron bunch spoiling effect and X-ray pulse when using the slotted foil. We show that few-femtosecond X-ray pulses are generated with flexible control of the single-pulse duration or double-pulse separation with comparison to the theoretical model.

  17. A model for the distribution of material generating the soft X-ray background

    NASA Technical Reports Server (NTRS)

    Snowden, S. L.; Cox, D. P.; Mccammon, D.; Sanders, W. T.

    1990-01-01

    The observational evidence relating to the soft X-ray diffuse background is discussed, and a simple model for its source and spatial structure is presented. In this simple model with one free parameter, the observed 1/4 keV X-ray intensity originates as thermal emission from a uniform hot plasma filling a cavity in the neutral material of the Galactic disk which contains the sun. Variations in the observed X-ray intensity are due to variations in the extent of the emission volume and therefore the emission measure of the plasma. The model reproduces the observed negative correlation between X-ray intensity and H I column density and predicts reasonable values for interstellar medium parameters.

  18. Principal component analysis of soft x-ray signals generated by the PF-1000 facility in experiments with solid targets

    NASA Astrophysics Data System (ADS)

    Kowalska-Strzęciwilk, Ewa; Skrzeczanowski, Wojciech; Czarnecka, Agata; Kubkowska, Monika; Paduch, Marian; Zielińska, Ewa

    2014-05-01

    The paper presents the analysis of soft x-ray signals generated in the PF-1000 facility equipped with a modified inner electrode with a central tungsten insert of 50 mm diameter in experiments with tungsten and carbon samples. The PF-1000 machine was operated with pure deuterium filling under the initial pressure of 1.3 hPa. The machine was powered using a condenser bank charged initially to 24 kV, corresponding to the stored energy of 380 kJ, with the maximum discharge current amounted to 1.8 MA. For investigation of plasma stream-sample interactions, we applied 16-frame laser interferometry, optical spectroscopy and soft x-ray measurements with the use of a system of four silicon pin-diodes. In this paper, we mainly focus on the principal component analysis (PCA) of the registered x-ray signals to find a corelation between the neutron yield and observed maxima in signals. X-ray signals collected by four pin-diodes covered a 9 cm range in front of the electrode ends. Each diode collected a signal from the circle of 3 cm diameter. The presented PCA analysis is based on 57 PF discharges and 16 parameters are taken into account in the analysis. The study of signals from the pin-diode system showed good correlation between the neutron yield and the maximum in the x-ray signal, which appeared about 1000-1300 ns after the maximum of plasma compression.

  19. Investigating radial wire array Z pinches as a compact x-ray source on the Saturn generator

    DOE PAGES

    Ampleford, David J.; Bland, S. N.; Jennings, Christopher A.; ...

    2015-08-27

    Radial wire array z pinches, where wires are positioned radially outward from a central cathode to a concentric anode, can act as a compact bright x-ray source that could potentially be used to drive a hohlraum. Experiments were performed on the 7-MA Saturn generator using radial wire arrays. These experiments studied a number of potential risks in scaling radial wire arrays up from the 1-MA level, where they have been shown to be a promising compact X-ray source. Data indicates that at 7 MA, radial wire arrays can radiate ~9 TW with 10-ns full-width at half-maximum from a compact pinch.

  20. Generation of attosecond x-ray pulses with a multi-cycle two-color ESASE scheme

    SciTech Connect

    Ding, Y.; Huang, Z.; Ratner, D.; Bucksbaum, P.; Merdji, H.; /SLAC, PULSE

    2008-09-30

    Generation of attosecond x-ray pulses is attracting much attention within the x-ray free-electron laser (FEL) user community. Several schemes have been proposed based on manipulations of electron bunches with extremely short laser pulses. In this paper, we extend the attosecond two-color ESASE scheme proposed by Zholents et al. to the long optical cycle regime using a detuned second laser and a tapered undulator. Both lasers can be about ten-optical-cycles long, with the second laser frequency detuned from the first one to optimize the contrast between the central and side current spikes. A tapered undulator mitigates the degradation effect of the longitudinal space charge (LSC) force in the undulator and suppresses the FEL gain of all side current spikes. Simulations using the LCLS parameters show a single attosecond x-ray spike of {approx} 110 attosecond can be produced with a good contrast ratio.

  1. BEAM DYNAMICS STUDIES OF A HIGH-REPETITION RATE LINAC-DRIVER FOR A 4TH GENERATION LIGHT SOURCE

    SciTech Connect

    Ventturini, M.; Corlett, J.; Emma, P.; Papadopoulos, C.; Penn, G.; Placidi, M.; Qiang, J.; Reinsch, M.; Sannibale, F.; Steier, C.; Sun, C.; Wells, R.

    2012-05-18

    We present recent progress toward the design of a super-conducting linac driver for a high-repetition rate FEL-based soft x-ray light source. The machine is designed to accept beams generated by the APEX photo-cathode gun operating with MHz-range repetition rate and deliver them to an array of SASE and seeded FEL beamlines. We review the current baseline design and report results of beam dynamics studies.

  2. Diagnostic copper imaging of Menkes disease by synchrotron radiation-generated X-ray fluorescence analysis

    PubMed Central

    Kinebuchi, Miyuki; Matsuura, Akihiro; Kiyono, Tohru; Nomura, Yumiko; Kimura, Sachiko

    2016-01-01

    Copper (Cu) is an indispensable metal for normal development and function of humans, especially in central nervous system (CNS). However, its redox activity requires accurate Cu transport system. ATP7A, a main Cu2+ transporting-ATPase, is necessary to efflux Cu across the plasma membrane and synthesize cuproenzymes. Menkes disease (MD) is caused by mutations in ATP7A gene. Clinically, MD is Cu deficiency syndrome and is treated with Cu-histidine injections soon after definite diagnosis. But outcome of the most remains poor. To estimate the standard therapy, Cu distribution in the treated classic MD patients is analyzed by synchrotron-generated X-ray fluorescence technique (SR-XRF), which identifies and quantifies an individual atom up to at subcellular level of resolution with wide detection area. SR-XRF analysis newly reveals that Cu exists in spinal cord parenchyma and flows out via venous and lymph systems. By systemic analysis, excess Cu is detected in the proximal tubular cells of the kidney, the mucosal epithelial cells of the intestine, and the lymph and venous systems. The current study suggests that the standard therapy supply almost enough Cu for patient tissues. But given Cu passes through the tissues to venous and lymph systems, or accumulate in the cells responsible for Cu absorption. PMID:27629586

  3. Next Generation X-ray Optics: High Angular Resolution, Light Weight, and Low Production Cost

    NASA Astrophysics Data System (ADS)

    Zhang, William

    2013-01-01

    Since its beginning 50 years ago, X-ray astronomy has advanced by leaps and bounds, culminating in its current golden age in which three major observatories—Chandra, XMM-Newton, and Suzaku—are operating simultaneously and addressing some of the most important astronomical and astrophysical problems of our time. Building upon this success, the recent Decadal Survey of Astronomy and Astrophysics has defined objectives for x-ray astronomy whose realization requires both new optics and new detector technologies. The development of these technologies has been identified as one of the highest priorities for funding to enable future x-ray missions. X-ray optics technology based on precision glass slumping is on the verge of revolutionizing x-ray telescope making. It has shown that extremely thin (< 0.4mm) and lightweight (areal density < 1 kg/m2) true Wolter-I mirror segments with angular resolutions better than 7 arc-seconds can be fabricated consistently, efficiently, and inexpensively. In comparison with those of XMM-Newton, these mirror segments represent a factor of 10 reduction in mass while achieving slightly better angular resolution. In comparison with those of Suzaku, they represent a factor of 20 improvement in angular resolution while maintaining the same mass areal density. These advances have been demonstrated with x-ray images from aligned and bonded mirror segments. In short, this technology is approaching TRL-5 for making the mirror assemblies required for a 10 arc-second observatory. In this poster we will present the latest x-ray and environment test results obtained with technology development modules which are substantially similar to flight modules in the way they constructed and tested.

  4. Generation of bright attosecond x-ray pulse trains via Thomson scattering from laser-plasma accelerators.

    PubMed

    Luo, W; Yu, T P; Chen, M; Song, Y M; Zhu, Z C; Ma, Y Y; Zhuo, H B

    2014-12-29

    Generation of attosecond x-ray pulse attracts more and more attention within the advanced light source user community due to its potentially wide applications. Here we propose an all-optical scheme to generate bright, attosecond hard x-ray pulse trains by Thomson backscattering of similarly structured electron beams produced in a vacuum channel by a tightly focused laser pulse. Design parameters for a proof-of-concept experiment are presented and demonstrated by using a particle-in-cell code and a four-dimensional laser-Compton scattering simulation code to model both the laser-based electron acceleration and Thomson scattering processes. Trains of 200 attosecond duration hard x-ray pulses holding stable longitudinal spacing with photon energies approaching 50 keV and maximum achievable peak brightness up to 1020 photons/s/mm2/mrad2/0.1%BW for each micro-bunch are observed. The suggested physical scheme for attosecond x-ray pulse trains generation may directly access the fastest time scales relevant to electron dynamics in atoms, molecules and materials.

  5. High Energy X-Ray Source Generation by Short Pulse High Intensity Lasers

    SciTech Connect

    Park, H-S; Koch, J A; Landen, O L; Phillips, T W; Goldsack, T; Clark, E; Eagleton, R; Edwards, R

    2003-09-02

    We are studying the feasibility of utilizing K{alpha} x-ray sources in the range of 20 to 100 keV as a backlighters for imaging various stages of implosions and high areal density planar samples driven by the NIF laser facility. The hard x-ray K{alpha} sources are created by relativistic electron plasma interactions in the target material after a radiation by short pulse high intensity lasers. In order to understand K{alpha} source characteristics such as production efficiency and brightness as a function of laser parameters, we have performed experiments using the 10 J, 100 fs JanUSP laser. We utilized single-photon counting spectroscopy and x-ray imaging diagnostics to characterize the K{alpha} source. We find that the K{alpha} conversion efficiency from the laser energy at 22 keV is {approx} 3 x 10{sup -4}.

  6. Femtosecond laser-generated high-energy-density states studied by x-ray FELs

    NASA Astrophysics Data System (ADS)

    Nakatsutsumi, M.; Appel, K.; Baehtz, C.; Chen, B.; Cowan, T. E.; Göde, S.; Konopkova, Z.; Pelka, A.; Priebe, G.; Schmidt, A.; Sukharnikov, K.; Thorpe, I.; Tschentscher, Th; Zastrau, U.

    2017-01-01

    The combination of powerful optical lasers and an x-ray free-electron laser (XFEL) provides unique capabilities to study the transient behaviour of matter in extreme conditions. The high energy density science instrument (HED instrument) at the European XFEL will provide the experimental platform on which an unique x-ray source can be combined with various types of high-power optical lasers. In this paper, we highlight selected scientific examples together with the associated x-ray techniques, with particular emphasis on femtosecond (fs)-timescale pump-probe experiments. Subsequently, we present the current design status of the HED instrument, outlining how the experiments could be performed. First user experiments will start at the beginning of 2018, after which various optical lasers will be commissioned and made available to the international scientific community.

  7. Enhancement of x-rays generated by a guided laser wakefield accelerator inside capillary tubes

    SciTech Connect

    Ju, J.; Doepp, A.; Cassou, K.; Neveu, O.; Cros, B.; Svensson, K.; Genoud, G.; Wojda, F.; Burza, M.; Persson, A.; Lundh, O.; Wahlstroem, C.-G.; Ferrari, H. E.

    2012-05-07

    Electrons accelerated in the nonlinear regime in a laser wakefield accelerator experience transverse oscillations inside the plasma cavity, giving rise to ultra-short pulsed x-rays, also called the betatron radiation. We show that the fluence of x-ray can be enhanced by more than one order of magnitude when the laser is guided by a 10 mm long capillary tube instead of interacting with a 2 mm gas jet. X-rays with a synchrotron-like spectrum and associated critical energy {approx}5 keV, with a peak brightness of {approx}1x10{sup 21} ph/s/mm{sup 2}/mrad{sup 2}/0.1%BW, were achieved by employing 16 TW laser pulses.

  8. X-ray crystallography

    NASA Technical Reports Server (NTRS)

    2001-01-01

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

  9. Tunable X-ray source

    DOEpatents

    Boyce, James R [Williamsburg, VA

    2011-02-08

    A method for the production of X-ray bunches tunable in both time and energy level by generating multiple photon, X-ray, beams through the use of Thomson scattering. The method of the present invention simultaneously produces two X-ray pulses that are tunable in energy and/or time.

  10. Generation of attosecond x-ray pulses with a multi-cycle two-color ESASE scheme

    SciTech Connect

    Ding, Y.; Huang, Z.; Ratner, D.; Bucksbaum, P.; Merdji, H.; /Saclay /SLAC

    2009-03-04

    Generation of attosecond x-ray pulses is attracting much attention within the x-ray free-electron laser (FEL) user community. Several schemes using extremely short laser pulses to manipulate the electron bunches have been proposed. In this paper, we extend the attosecond two-color ESASE scheme proposed by Zholents et al. to the long optical cycle regime using a second detuned laser and a tapered undulator. Both lasers can be about ten-optical-cycles long, with the second laser frequency detuned from the first to optimize the contrast between the central and side current spikes. A tapered undulator mitigates the degradation effect of the longitudinal space charge (LSC) force in the undulator and suppresses the FEL gain of all side current peaks. Simulations using the LCLS parameters show a single attosecond x-ray spike of {approx} 110 attoseconds can be produced. The second laser can also be detuned to coherently control the number of the side x-ray spikes and the length of the radiation pulse.

  11. Shock-generated X-ray emission in radiatively driven winds - A model for Tau Scorpii

    NASA Technical Reports Server (NTRS)

    Macfarlane, Joseph J.; Cassinelli, Joseph P.

    1989-01-01

    A one-dimensional radiation-hydrodynamics code is used to numerically investigate the structure and evolution of shocks in the winds of hot stars. Results are presented for the specific case of Tau Sco, a well-studied main-sequence B star for which there are X-ray data from the Einstien satellite's Solid State Spectrometer. A phenomenological radiative acceleration term and a mass-loss rate consistent with UV observations, are used to determine the time dependence of the temperatures within and X-ray emission from an isolated shock region. The driving acceleration leads to the formation of a two-component shock zone with 'forward' and 'reverse' shocks, each with their own characteristic temperature. A denser cold region forms between the two shocks, which could potentially account for the presence of narrow absorption features that are observed in the UV P Cygni profiles of many hot stars. The X-ray emission spectra from the shocks in the calculations are in good general agreement with two-temperature model fits to Einstein X-ray observations.

  12. Specific features of X-ray generation by plasma focus chambers with deuterium and deuterium-tritium fillings

    NASA Astrophysics Data System (ADS)

    Dulatov, A. K.; Krapiva, P. S.; Lemeshko, B. D.; Mikhailov, Yu. V.; Moskalenko, I. N.; Prokuratov, I. A.; Selifanov, A. N.

    2016-01-01

    The process of hard X-ray (HXR) generation in plasma focus (PF) chambers was studied experimentally. The radiation was recorded using scintillation detectors with a high time resolution and thermoluminescent detectors in combination with the method of absorbing filters. Time-resolved analysis of the processes of neutron and X-ray generation in PFs is performed. The spectra of HXR emission from PF chambers with deuterium and deuterium-tritium fillings are determined. In experiments with PF chambers filled with a deuterium-tritium mixture, in addition to the HXR pulse with photon energies of up to 200-300 keV, a γ-ray pulse with photon energies of up to 2.5-3.0 MeV is recorded, and a mechanism of its generation is proposed.

  13. Specific features of X-ray generation by plasma focus chambers with deuterium and deuterium–tritium fillings

    SciTech Connect

    Dulatov, A. K. Krapiva, P. S.; Lemeshko, B. D.; Mikhailov, Yu. V.; Moskalenko, I. N.; Prokuratov, I. A.; Selifanov, A. N.

    2016-01-15

    The process of hard X-ray (HXR) generation in plasma focus (PF) chambers was studied experimentally. The radiation was recorded using scintillation detectors with a high time resolution and thermoluminescent detectors in combination with the method of absorbing filters. Time-resolved analysis of the processes of neutron and X-ray generation in PFs is performed. The spectra of HXR emission from PF chambers with deuterium and deuterium–tritium fillings are determined. In experiments with PF chambers filled with a deuterium–tritium mixture, in addition to the HXR pulse with photon energies of up to 200–300 keV, a γ-ray pulse with photon energies of up to 2.5–3.0 MeV is recorded, and a mechanism of its generation is proposed.

  14. Reliability of a new 4th generation FloTrac algorithm to track cardiac output changes in patients receiving phenylephrine.

    PubMed

    Ji, Fuhai; Li, Jian; Fleming, Neal; Rose, David; Liu, Hong

    2015-08-01

    Phenylephrine is often used to treat intra-operative hypotension. Previous studies have shown that the FloTrac cardiac monitor may overestimate cardiac output (CO) changes following phenylephrine administration. A new algorithm (4th generation) has been developed to improve performance in this setting. We performed a prospective observational study to assess the effects of phenylephrine administration on CO values measured by the 3rd and 4th generation FloTrac algorithms. 54 patients were enrolled in this study. We used the Nexfin, a pulse contour method shown to be insensitive to vasopressor administration, as the reference method. Radial arterial pressures were recorded continuously in patients undergoing surgery. Phenylephrine administration times were documented. Arterial pressure recordings were subsequently analyzed offline using three different pulse contour analysis algorithms: FloTrac 3rd generation (G3), FloTrac 4th generation (G4), and Nexfin (nf). One minute of hemodynamic measurements was analyzed immediately before phenylephrine administration and then repeated when the mean arterial pressure peaked. A total of 157 (4.6 ± 3.2 per patient, range 1-15) paired sets of hemodynamic recordings were analyzed. Phenylephrine induced a significant increase in stroke volume (SV) and CO with the FloTrac G3, but not with FloTrac G4 or Nexfin algorithms. Agreement between FloTrac G3 and Nexfin was: 0.23 ± 1.19 l/min and concordance was 51.1%. In contrast, agreement between FloTrac G4 and Nexfin was: 0.19 ± 0.86 l/min and concordance was 87.2%. In conclusion, the pulse contour method of measuring CO, as implemented in FloTrac 4th generation algorithm, has significantly improved its ability to track the changes in CO induced by phenylephrine.

  15. Simbol-X: A New Generation Soft/Hard X-ray Telescope

    NASA Astrophysics Data System (ADS)

    Slane, Patrick O.; Romaine, S.; Murray, S. S.; Brissenden, R.; Elvis, M.; Gorenstein, P.; Steel, S.; O'Dell, S.; Kolodziejczak, J.; Ramsey, B.; Angelini, L.; Citterio, O.; Pareschi, G.

    2008-03-01

    Simbol-X is arguably the most powerful broad-band focusing hard (0.5-80 keV) X-ray telescope operating in the 2013 timeframe. The combination of good angular resolution, broad energy response, and efficient observing provided by a good field of view and high orbit will provide a very large increase in sensitivity in a hitherto relatively unexplored spectral region. This will enable key scientific investigations including a census of supermassive black holes in the crucial energy range in which the cosmic X-ray background peaks, measurements of the geometry and dynamics of accretion in black hole binaries, characterization of hard X-ray sources in the Galactic center, and the nature and origin of energetic particles in galaxy clusters and supernova remnants. Its single optics module contains a set of nested nickel shells coated with multilayers to boost the high-energy response and the field of view. Its focal plane detectors are a novel hybrid configuration, with thick-depletion silicon providing the low energy response, and Cadmium Telluride the high energy response. To achieve the long focal length necessary for large collecting areas at high energies, the optics and detectors are on separate high-earth-orbit formation-flying spacecrafts, 20 m apart. We describe a proposed US participation in the Simbol-X program to provide technical expertise in the area of multilayer coatings for the X-ray optics; expertise in science and the X-ray testing and calibration of the flight optics; and support as a data analysis, Guest Investigator, and archiving center. The use of the NASA DSN Goldstone station, as a complement to the Malindi tracking station,will also be provided.

  16. Characterisation of flash X-ray source generated by Kali-1000 Pulse Power System

    NASA Astrophysics Data System (ADS)

    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.

  17. First results of KALI-30 GW with 1 MV flash X-rays generation and characterization by Imaging plate

    NASA Astrophysics Data System (ADS)

    Sharma, A.; Shaikh, A. M.; Senthil, K.; Mitra, S.; Chandra, R.; Vishnu, S.; Sandeep, S.; Roy, A.; Rakhee, M.; Sharma, V.; Danish, M. B.; Kolge, T. S.; Ranjeet, K.; Agrawal, R.; Saroj, P. C.; Tewari, S. V.; Mittal, K. C.

    2014-07-01

    The design, development and commissioning of 1 MV pulsed electron accelerator producing Flash X-Rays is described in this paper. This pulsed power system is based on bipolar MARX generator and Blumlein followed by Explosive electron emission diode assembly. The peak pulsed power is ~ 30 GW. The electron energies in the range of 400 keV to 1030 keV are produced and delivered to experimental load of Industrial diode. Electrons are emitted from a stainless steel ring at ground potential by explosive field emission and bombard the anode tungsten pin for flash X-rays generation. The relativistic electron beam has been simulated within the diode chamber and pattern shows the beam propagation. Imaging plates are used to characterize the source size and optimization has been reported.

  18. High-Flux Femtosecond X-Ray Emission from Controlled Generation of Annular Electron Beams in a Laser Wakefield Accelerator.

    PubMed

    Zhao, T Z; Behm, K; Dong, C F; Davoine, X; Kalmykov, S Y; Petrov, V; Chvykov, V; Cummings, P; Hou, B; Maksimchuk, A; Nees, J A; Yanovsky, V; Thomas, A G R; Krushelnick, K

    2016-08-26

    Annular quasimonoenergetic electron beams with a mean energy in the range 200-400 MeV and charge on the order of several picocoulombs were generated in a laser wakefield accelerator and subsequently accelerated using a plasma afterburner in a two-stage gas cell. Generation of these beams is associated with injection occurring on the density down ramp between the stages. This well-localized injection produces a bunch of electrons performing coherent betatron oscillations in the wakefield, resulting in a significant increase in the x-ray yield. Annular electron distributions are detected in 40% of shots under optimal conditions. Simultaneous control of the pulse duration and frequency chirp enables optimization of both the energy and the energy spread of the annular beam and boosts the radiant energy per unit charge by almost an order of magnitude. These well-defined annular distributions of electrons are a promising source of high-brightness laser plasma-based x rays.

  19. Study of a possible X-ray sensor based on the Plasmon Surface Resonance for the next generation of instruments

    NASA Astrophysics Data System (ADS)

    Hervé, Anthony; Hastanin, Juriy; Habraken, Serge; Rauw, Gregor

    2011-01-01

    With the new generation of X-ray space observatories, such as IXO in preparation, we explore a new technology in order to improve the spectral resolution and the sensitivity of future instruments. We have studied the possibility to create a sensor based on the Surface Plasmon Resonance (SPR), already used in chemistry and biomedical applications, and have determined the preliminary constraints on its size, energy resolution and working temperature.

  20. Generation of ultra-large-bandwidth X-ray free-electron-laser pulses with a transverse-gradient undulator

    PubMed Central

    Prat, Eduard; Calvi, Marco; Reiche, Sven

    2016-01-01

    A new and simple method to generate X-ray free-electron-laser radiation with unprecedented spectral bandwidth above the 10% level is presented. The broad bandwidth is achieved by sending a transversely tilted beam through a transverse-gradient undulator. The extent of the bandwidth can easily be controlled by variation of the beam tilt or the undulator gradient. Numerical simulations confirm the validity and feasibility of this method. PMID:27359135

  1. Atomic Data Needs for the New Generation of X-ray Observatories

    NASA Astrophysics Data System (ADS)

    Garcia, Javier; 6174967980

    2016-06-01

    Modeling X-ray spectra produced by photoionized plasmas is crucial for the physical interpretation of many astrophysical sources. These models rely on theoretical and numerical techniques, but importantly also on the availability of reliable atomic data. The need for accurate data continues to grow with the advent of new and more sensitive instruments. I will describe atomic-data requirements for addressing three astrophysical problems: (1) atomic, molecular, and dust absorption in the ISM; (2) detection and characterization of inner-shell lines from various trace elements or Fe-peak elements (e.g., P, K, Cr, Mn, Co); and (3) modeling X-ray spectra reflected from black hole accretion disks in the high-density limit. I will discuss the importance ofthese studies, and the limitations of the theoretical models presently being used to fit data from such current missions as NuSTAR and Astro-H (Hitomi).

  2. Generation of large-bandwidth x-ray free-electron-laser pulses

    NASA Astrophysics Data System (ADS)

    Saa Hernandez, Angela; Prat, Eduard; Bettoni, Simona; Beutner, Bolko; Reiche, Sven

    2016-09-01

    X-ray free-electron lasers (XFELs) are modern research tools in disciplines such as biology, material science, chemistry, and physics. Besides the standard operation that aims at minimizing the bandwidth of the produced XFEL radiation, there is a strong scientific demand to produce large-bandwidth XFEL pulses for several applications such as nanocrystallography, stimulated Raman spectroscopy, and multiwavelength anomalous diffraction. We present a self-consistent method that maximizes the XFEL pulse bandwidth by systematically maximizing the energy chirp of the electron beam at the undulator entrance. This is achieved by optimizing the compression scheme and the electron distribution at the source in an iterative back-and-forward tracking. Start-to-end numerical simulations show that a relative bandwidth of 3.25% full-width can be achieved for the hard x-ray pulses in the SwissFEL case.

  3. Instrumentation for a next-generation x-ray all-sky monitor

    SciTech Connect

    Peele, A. G.

    1999-12-15

    We have proposed an x-ray all-sky monitor for a small satellite mission that will be ten times more sensitive than past monitors and that opens up a new band of the soft x-ray spectrum (0.1-3.0 keV) for study. We discuss three approaches to the construction of the optics. The first method, well within the reach of existing technology, is to approximate the lobster-eye geometry by building crossed arrays of planar reflectors, this gives great control over the reflecting surface but is limited in terms of resolution at the baseline 4 arc minute level. The second method is to use microchannel plates; this technology has the potential to greatly exceed the baseline resolution and sensitivity but is yet to be fully demonstrated. The third method, while still in its infancy, may yet prove to be the most powerful; this approach relies on photolithography to expose a substrate that can then be developed and replicated. The scientific case for this mission is almost too broad to state here. The instrument we describe will allow investigation of the long term light curves of thousands of AGN, it will detect thousands of transients, including GRBs and type II supernova, and the stellar coronae of hundreds of the brightest x-ray stars can be monitored. In addition the classical objectives of all-sky monitors--long-term all-sky archive and watchdog alert to new events--will be fulfilled at an unprecedented level. We also note that by opening up a little-explored band of the x-ray sky the opportunity for new discovery is presented. A satisfying example of entering new territory while still retaining the guarantee of expanding the domain of existing research.

  4. Optimizing x-ray mirror thermal performance using variable length cooling for second generation FELs

    NASA Astrophysics Data System (ADS)

    Hardin, Corey L.; Srinivasan, Venkat N.; Amores, Lope; Kelez, Nicholas M.; Morton, Daniel S.; Stefan, Peter M.; Nicolas, Josep; Zhang, Lin; Cocco, Daniele

    2016-09-01

    The success of the LCLS led to an interest across a number of disciplines in the scientific community including physics, chemistry, biology, and material science. Fueled by this success, SLAC National Accelerator Laboratory is developing a new high repetition rate free electron laser, LCLS-II, a superconducting linear accelerator capable of a repetition rate up to 1 MHz. Undulators will be optimized for 200 to 1300 eV soft X-rays, and for 1000 to 5000 eV hard X-rays. To absorb spontaneous radiation, higher harmonic energies and deflect the x-ray beam to various end stations, the transport and diagnostics system includes grazing incidence plane mirrors on both the soft and Hard X-ray beamline. To deliver the FEL beam with minimal power loss and wavefront distortion, we need mirrors of height errors below 1nm rms in operational conditions. We need to mitigate the thermal load effects due to the high repetition rate. The absorbed thermal profile is highly dependent on the beam divergence, and this is a function of the photon energy. To address this complexity, we developed a mirror cradle with variable length cooling and first order curve correction. Mirror figure error is minimized using variable length water-cooling through a gallium-indium eutectic bath. Curve correction is achieved with an off-axis bender that will be described in details. We present the design features, mechanical analysis and results from optical and mechanical tests of a prototype assembly, with particular regards to the figure sensitivity to bender corrections.

  5. Suppression of x-rays generated by runaway electrons in ATF

    SciTech Connect

    Rasmussen, D.A.; England, A.C.; Eberle, C.C.; Devan, W.R.; Harris, J.H.; Jernigan, T.C.; Kindsfather, R.R.; Morris, R.N.; Murakami, M.; Neilson, G.H.

    1987-01-01

    X-ray emission from runaway electrons on ATF is a serious issue. Runaway suppression techniques used on Heliotron-E are not adequate for ATF. Three approaches have been developed to suppress runaway production. Monitoring devices have been installed in occupied areas and personnel access and exposure will be limited. Additional shielding will be added as required. These systems will be ready for installation and testing on ATF prior to commissioning or first plasma operation.

  6. DynamiX, numerical tool for design of next-generation x-ray telescopes.

    PubMed

    Chauvin, Maxime; Roques, Jean-Pierre

    2010-07-20

    We present a new code aimed at the simulation of grazing-incidence x-ray telescopes subject to deformations and demonstrate its ability with two test cases: the Simbol-X and the International X-ray Observatory (IXO) missions. The code, based on Monte Carlo ray tracing, computes the full photon trajectories up to the detector plane, accounting for the x-ray interactions and for the telescope motion and deformation. The simulation produces images and spectra for any telescope configuration using Wolter I mirrors and semiconductor detectors. This numerical tool allows us to study the telescope performance in terms of angular resolution, effective area, and detector efficiency, accounting for the telescope behavior. We have implemented an image reconstruction method based on the measurement of the detector drifts by an optical sensor metrology. Using an accurate metrology, this method allows us to recover the loss of angular resolution induced by the telescope instability. In the framework of the Simbol-X mission, this code was used to study the impacts of the parameters on the telescope performance. In this paper we present detailed performance analysis of Simbol-X, taking into account the satellite motions and the image reconstruction. To illustrate the versatility of the code, we present an additional performance analysis with a particular configuration of IXO.

  7. DynamiX, numerical tool for design of next-generation x-ray telescopes

    SciTech Connect

    Chauvin, Maxime; Roques, Jean-Pierre

    2010-07-20

    We present a new code aimed at the simulation of grazing-incidence x-ray telescopes subject to deformations and demonstrate its ability with two test cases: the Simbol-X and the International X-ray Observatory (IXO) missions. The code, based on Monte Carlo ray tracing, computes the full photon trajectories up to the detector plane, accounting for the x-ray interactions and for the telescope motion and deformation. The simulation produces images and spectra for any telescope configuration using Wolter I mirrors and semiconductor detectors. This numerical tool allows us to study the telescope performance in terms of angular resolution, effective area, and detector efficiency, accounting for the telescope behavior. We have implemented an image reconstruction method based on the measurement of the detector drifts by an optical sensor metrology. Using an accurate metrology, this method allows us to recover the loss of angular resolution induced by the telescope instability. In the framework of the Simbol-X mission, this code was used to study the impacts of the parameters on the telescope performance. In this paper we present detailed performance analysis of Simbol-X, taking into account the satellite motions and the image reconstruction. To illustrate the versatility of the code, we present an additional performance analysis with a particular configuration of IXO.

  8. Double-confocal resonator for X-ray generation via intracavity Thomson scattering

    SciTech Connect

    Xie, M.

    1995-12-31

    There has been a growing interest in developing compact X-ray sources through Thomson scattering of a laser beam by a relativistic electron beam. For higher X-ray flux it is desirable to have the scattering to occur inside an optical resonator where the laser power is higher. In this paper I propose a double-confocal resonator design optimized for head-on Thomson scattering inside an FEL oscillator and analyze its performance taking into account the diffraction and FEL gain. A double confocal resonator is equivalent to two confocal resonators in series. Such a resonator has several advantages: it couples electron beam through and X-ray out of the cavity with holes on cavity mirrors, thus allowing the system to be compact; it supports the FEL mode with minimal diffraction loss through the holes; it provides a laser focus in the forward direction for a better mode overlap with the electron beam; and it provides a focus at the same location in the backward direction for higher Thomson scattering efficiency; in addition, the mode size at the focal point and hence the Rayleigh range can be adjusted simply through intracavity apertures; furthermore, it gives a large mode size at the mirrors to reduce power loading. Simulations as well as analytical results will be presented. Also other configurations of intracavity Thomson scattering where the double-confocal resonator could be useful will be discussed.

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

    NASA Technical Reports Server (NTRS)

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

    2014-01-01

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

  10. SuperHERO: The Next Generation Hard X-ray HEROES Telescope

    NASA Technical Reports Server (NTRS)

    Gaskin, Jessica A.; Christe, Steven D.; Wilson-Hodge, Colleen; Shih, Albert Y. M.; Ramsey, Brian D.; Tennant, Allyn F.; Swartz, Douglas A.

    2014-01-01

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

  11. Relativistically Self-Channeled Femtosecond Terawatt Lasers for High-Field Physics and X-Ray Generation

    SciTech Connect

    Borisov, A.B.; Boyer, K.; Cameron, S.M.; Luk, T.S.; McPherson, A.; Nelson, T.; Rhodes, C.K.

    1999-01-01

    Optical channeling or refractive guiding processes involving the nonlinear interaction of intense femtosecond optical pulses with matter in the self-focussing regime has created exciting opportunities for next-generation laser plasma-based x-ray sources and directed energy applications. This fundamentally new form of extended paraxial electromagnetic propagation in nonlinear dispersive media such as underdense plasma is attributed to the interplay between normal optical diffraction and intensity-dependent nonlinear focussing and refraction contributions in the dielectric response. Superposition of these mechanisms on the intrinsic index profile acts to confine the propagating energy in a dynamic self-guiding longitudinal waveguide structure which is stable for power transmission and robust compression. The laser-driven channels are hypothesized to support a degree of solitonic transport behavior, simultaneously stable in the space and time domains (group velocity dispersion balances self-phase modulation), and are believed to be self-compensating for diffraction and dispersion over many Rayleigh lengths in contrast with the defining characteristics of conventional diffractive imaging and beamforming. By combining concentrated power deposition with well-ordered spatial localization, this phenomena will also create new possibilities for production and regulation of physical interactions, including electron beams, enhanced material coupling, and self-modulated plasma wakefields, over extended gain distances with unprecedented energy densities. Harmonious combination of short-pulse x-ray production with plasma channeling resulting from a relativistic charge displacement nonlinearity mechanism in the terawatt regime (10{sup 18} W/cm{sup 2}) has been shown to generate high-field conditions conducive to efficient multi-kilovolt x-ray amplification and peak spectral brightness. Channeled optical propagation with intense short-pulse lasers is expected to impact several

  12. 53 W average power few-cycle fiber laser system generating soft x rays up to the water window.

    PubMed

    Rothhardt, Jan; Hädrich, Steffen; Klenke, Arno; Demmler, Stefan; Hoffmann, Armin; Gotschall, Thomas; Eidam, Tino; Krebs, Manuel; Limpert, Jens; Tünnermann, Andreas

    2014-09-01

    We report on a few-cycle laser system delivering sub-8-fs pulses with 353 μJ pulse energy and 25 GW of peak power at up to 150 kHz repetition rate. The corresponding average output power is as high as 53 W, which represents the highest average power obtained from any few-cycle laser architecture so far. The combination of both high average and high peak power provides unique opportunities for applications. We demonstrate high harmonic generation up to the water window and record-high photon flux in the soft x-ray spectral region. This tabletop source of high-photon flux soft x rays will, for example, enable coherent diffractive imaging with sub-10-nm resolution in the near future.

  13. Dynamics and X-ray emission of an X-pinch conducted on a small capacitive generator

    NASA Astrophysics Data System (ADS)

    Pavez, Cristian; Avaria, Gonzalo; Moreno, Jose; San Martin, Patricio; Soto, Leopoldo; Sepulveda, Adolfo; Pedreros, Jose

    2014-10-01

    The characterization of the dynamics and X-ray emission of a X-pinch configuration conducted in a compact capacitive generator are presented. The experimental measurements were carried out on a multi-purpose generator (1.2 micro F, 345 J, 47.5 nH, T/4 = 375 ns and Z = 0.2 Ohm in short circuit) which produces currents up to 122 kA with 500 ns quarter period, when wire load are used. Dark-field Schlieren and interferometry techniques were used to characterize the dynamics of the precursor plasma, plasma flares and plasma jet on the axes. The X-ray emission and the source size are evaluated with filtered PIN-diodes and aperture imaging technique respectively. In addition, X-ray plasma imaging and radiographic applications are presented. The experiments were conducted on W wires of different diameters. The experimental observations show a similar dynamic to those observed in experiments of higher current and shorter quarter period. Work supported by PIA CONICYT Grant ACT-1115, PAI CONICYT 791100020 and FONDECYT Iniciacion 11121587.

  14. Progress on the Development of the Next Generation X-ray Beam Position Monitors at the Advanced Photon Source

    SciTech Connect

    Lee, S.H.; Yang, B.X.; Decker, G.; Sereno, N.; Ramanathan, M.

    2016-07-27

    Accurate and stable x-ray beam position monitors (XBPMs) are ke y elements in obtaining the desired user beam stability in the Advanced Photon Source (APS). The next generat ion XBPMs for high heat load front ends (HHL FEs) have been designed to meet these requirements by utilizing Cu K-edge x-ray fluorescence (XRF) from a pair of copper absorbers and have been installed at the front ends (FEs) of the APS. Com missioning data showed a significant performance improvement over the existing photoemission-based XBPMs. While a similar design concept can be applied for the canted undulator front ends, where two undulator beams are separated by 1.0-mrad, the lower beam power (< 10 kW) per undulator allows us to explore lower-cost solutions based on Compton scat tering from the diamond blades placed edge-on to the x- ray beam. A prototype of the Compton scattering XBPM system was i nstalled at 24-ID-A in May 2015. In this report, the design and test results for XRF-based XBPM and Compton scattering based XBPM are presented. Ongoing research related to the development of the next generation XBPMs on thermal contac t resistance of a joint between two solid bodies is also discussed

  15. Electron acceleration and generation of high-brilliance x-ray radiation in kilojoule, subpicosecond laser-plasma interactions

    NASA Astrophysics Data System (ADS)

    Ferri, J.; Davoine, X.; Kalmykov, S. Y.; Lifschitz, A.

    2016-10-01

    Petawatt, picosecond laser pulses offer rich opportunities in generating synchrotron x-rays. This paper concentrates on the regimes accessible with the PETAL laser, which is a part of the Laser Megajoule (LMJ) facility. We explore two physically distinct scenarios through Particle-in-Cell simulations. The first one realizes in a dense plasma, such that the period of electron Langmuir oscillations is much shorter than the pulse duration. Hallmarks of this regime are longitudinal breakup ("self-modulation") of the picosecond-scale laser pulse and excitation of a rapidly evolving broken plasma wake. It is found that electron beams with a charge of several tens of nC can be obtained, with a quasi-Maxwellian energy distribution extending to a few-GeV level. In the second scenario, at lower plasma densities, the pulse is shorter than the electron plasma period. The pulse blows out plasma electrons, creating a single accelerating cavity, while injection on the density downramp creates a nC quasi-monoenergetic electron bunch within the cavity. This bunch accelerates without degradation beyond 1 GeV. The x-ray sources in the self-modulated regime offer a high number of photons (˜1 012) with the slowly decaying energy spectra extending beyond 60 keV. In turn, quasimonoenergetic character of the electron beam in the blowout regime results in the synchrotron-like spectra with the critical energy around 10 MeV and a number of photons >1 09 . Yet, much smaller source duration and transverse size increase the x-ray brilliance by more than an order of magnitude against the self-modulated case, also favoring high spatial and temporal resolution in x-ray imaging. In all explored cases, accelerated electrons emit synchrotron x-rays of high brilliance, B >1 020 photons /s /mm2/mrad2/0.1 %BW . Synchrotron sources driven by picosecond kilojoule lasers may thus find an application in x-ray diagnostics on such facilities such as the LMJ or National Ignition Facility (NIF).

  16. Tunable coherent radiation at soft X-ray wavelengths: Generation and interferometric applications

    SciTech Connect

    Rosfjord, Kristine Marie

    2004-01-01

    The availability of high power, spectrally and spatially coherent soft x-rays (SXR) would facilitate a wide variety of experiments as this energy region covers the primary resonances of many magnetic and biological materials. Specifically, there are the carbon and oxygen K-edges that are critical for biological imaging in the water window and the L-edges of iron, nickel, and cobalt for which imaging and scattering studies can be performed. A new coherent soft X-ray branchline at the Advanced Light Source has begun operation (beamline 12.0.2). Using the third harmonic from an 8 cm period undulator, this branch delivers coherent soft x-rays with photon energies ranging from 200eV to 1keV. This branchline is composed of two sub-branches one at 14X demagnification and the other 8X demagnification. The former is optimized for use at 500eV and the latter at 800eV. Here the expected power from the third harmonic of this undulator and the beamline design and characterization is presented. The characterization includes measurements on available photon flux as well as a series of double pinhole experiments to determine the coherence factor with respect to transverse distance. The first high quality Airy patterns at SXR wavelengths are created with this new beamline. The operation of this new beamline allows for interferometry to be performed in the SXR region. Here an interferometric experiment designed to directly determine the index of refraction of a material under test is performed. Measurements are first made in the EUV region using an established beamline (beamline12.0.1) to measure silicon, ruthenium and tantalum silicon nitride. This work is then extended to the SXR region using beamline 12.0.2 to test chromium and vanadium.

  17. Measurements of laser generated soft X-ray emission from irradiated gold foils

    NASA Astrophysics Data System (ADS)

    Davis, J. S.; Frank, Y.; Raicher, E.; Fraenkel, M.; Keiter, P. A.; Klein, S. R.; Drake, R. P.; Shvarts, D.

    2016-11-01

    Soft x-ray emission from laser irradiated gold foils was measured at the Omega-60 laser system using the Dante photodiode array. The foils were heated with 2 kJ, 6 ns laser pulses and foil thicknesses were varied between 0.5, 1.0, and 2.0 μm. Initial Dante analysis indicates peak emission temperatures of roughly 100 eV and 80 eV for the 0.5 μm and 1.0 μm thick foils, respectively, with little measurable emission from the 2.0 μm foils.

  18. Two-Chicane Compressed Harmonic Generation of Soft X-Rays

    SciTech Connect

    Ratner, Daniel; Huang, Z.; Chao, A.; /SLAC

    2010-07-30

    We propose a simple single-stage scheme to produce fully coherent 3nm radiation. Seeding an electron bunch prior to compression simultaneously shortens the laser wavelength and duration, and increases the modulation amplitude. The final X-ray wavelength is tunable by controlling the compression factor with the RF phase. We propose a two chicane scheme that allows for nearly arbitrary modulation amplitudes, extending the method to photocathode beams. We also show that transportation of fine compressed modulation structure is feasible due to a canceling effect of the second chicane.

  19. Measurements of laser generated soft X-ray emission from irradiated gold foils

    DOE PAGES

    Davis, J. S.; Frank, Y.; Raicher, E.; ...

    2016-08-22

    We measured soft x-ray emission from laser irradiated gold foils at the Omega-60 laser system using the Dante photodiode array. The foils were heated with 2 kJ, 6ns laser pulses and foil thicknesses were varied between 0.5, 1.0, and 2.0 μm. Initial Dante analysis indicates peak emission temperatures of roughly 100 eV and 80 eV for the 0.5 μm and 1.0 μm thick foils, respectively, with little measurable emission from the 2.0 μm foils.

  20. Densification of sol-gel silica thin films induced by hard X-rays generated by synchrotron radiation.

    PubMed

    Innocenzi, Plinio; Malfatti, Luca; Kidchob, Tongjit; Costacurta, Stefano; Falcaro, Paolo; Marmiroli, Benedetta; Cacho-Nerin, Fernando; Amenitsch, Heinz

    2011-03-01

    In this article the effects induced by exposure of sol-gel thin films to hard X-rays have been studied. Thin films of silica and hybrid organic-inorganic silica have been prepared via dip-coating and the materials were exposed immediately after preparation to an intense source of light of several keV generated by a synchrotron source. The samples were exposed to increasing doses and the effects of the radiation have been evaluated by Fourier transform infrared spectroscopy, spectroscopic ellipsometry and atomic force microscopy. The X-ray beam induces a significant densification on the silica films without producing any degradation such as cracks, flaws or delamination at the interface. The densification is accompanied by a decrease in thickness and an increase in refractive index both in the pure silica and in the hybrid films. The effect on the hybrid material is to induce densification through reaction of silanol groups but also removal of the organic groups, which are covalently bonded to silicon via Si-C bonds. At the highest exposure dose the removal of the organic groups is complete and the film becomes pure silica. Hard X-rays can be used as an efficient and direct writing tool to pattern coating layers of different types of compositions.

  1. Hard X-ray generation in the turbulent plasma of solar flares

    NASA Astrophysics Data System (ADS)

    Charikov, Yu. E.; Shabalin, A. N.

    2016-12-01

    The influence of scattering of accelerated electrons in the turbulent plasma on the transformation of their distribution function is studied. The turbulence is connected with the emergence of magnetic inhomogeneities and ion-sound mode. The level of ion-sound turbulence is specified by the ratio W s/ nk B T e = 10-3, while the value of magnetic fluctuations is δB/B = 10-3. Different initial angular distributions of the function of accelerated-electron source are regarded: from isotropic to narrow directional distributions. For the chosen energy-density values of the ion-sound turbulence and the level of magnetic fluctuations, it is shown that both types of turbulence lead to a qualitative change in the hard X-ray brightness along the loop, moreover their influence was found to be different. Models with magnetic fluctuations and the ion sound can be distinguished not only by the difference in the hard X-ray distribution along the loop but also by the photon spectrum.

  2. A new generation of detectors for scanning x-ray beam imaging systems

    NASA Astrophysics Data System (ADS)

    Rommel, J. Martin

    2016-01-01

    Scanning x-ray beam imaging systems were first developed by American Science and Engineering, Inc. (AS&E) in the early 1970s [1]. Since then, these systems have found a wide range of applications in security inspection and non-destructive testing. Large-area detectors are most frequently used to collect backscattered radiation but smaller transmission detectors are also employed for selected applications. Until recently, only two basic detector designs have been used: large scintillator blocks with attached photomultiplier tubes (PMTs) or large-volume light-sealed boxes, lined with scintillating screens and port windows for PMTs. In both cases, the detectors have required considerable depth to provide acceptable light collection efficiency. A new design recently developed by AS&E relies on wavelength shifting fibres (WSF) for light collection. For the first time, this approach enables the construction of thin large-area detectors. Stacking layers of WSF ribbons and scintillating screens in varying combinations enables optimization of the detection efficiency for different applications. Taking separate readings from different layers provides an energy-sensitive signal combination. Energy sensitivity can be improved further by adding filtration between the signal channels. Several prototype configurations have been built and characterized for both backscatter and transmission imaging. A WSF-based detector has been commercialized for a transmission x-ray imaging application.

  3. Quasimonochromatic x-ray backlighting on the COrnell Beam Research Accelerator (COBRA) pulsed power generator.

    PubMed

    Knapp, P F; Greenly, J B; Gourdain, P A; Hoyt, C L; Pikuz, S A; Shelkovenko, T A; Hammer, D A

    2010-10-01

    Monochromatic x-ray backlighting has been employed with great success for imaging of plasmas with strong self-emission such as x-pinches and wire array z-pinches. However, implementation of a monochromatic backlighting system typically requires extremely high quality spherically bent crystals which are difficult to manufacture and can be prohibitively expensive. Furthermore, the crystal must have a direct line of sight to the object, which typically emits copious amounts of radiation and debris. We present a quasimonochromatic x-ray backlighting system which employs an elliptically bent mica crystal as the dispersive element. In this scheme a narrow band of continuum radiation is selected for imaging, instead of line radiation in the case of monochromatic imaging. The flat piece of mica is bent using a simple four-point bending apparatus that allows the curvature of the crystal to be adjusted in situ for imaging in the desired wavelength band. This system has the advantage that it is very cost effective, has a large aperture, and is extremely flexible. The principles of operation of the system are discussed and its performance is analyzed.

  4. HEXITEC: A next generation hard X-ray Detector for Solar Observations

    NASA Astrophysics Data System (ADS)

    Panessa, M.; Christe, S.; Shih, A.; Gaskin, J.; Wilson, M. D.; Seller, P.; Baumgartner, W.; Inglis, A. R.

    2015-12-01

    High angular resolution HXR optics require detectors with a large number of fine pixels in order to adequately sample the telescope point spread function (PSF) over the entire field of view. Recent developments at the Rutherford Appleton Laboratory (RAL) have resulted in a new hard X-ray (HXR) detector system with the smallest independent pixels currently available, 250 microns. This matches perfectly with the best angular resolution currently achievable by HXR focusing optics which is about 5 arcsec (FWHM). For a SMEX mission with a 15 meter focal length each pixel would cover an angular size of about 3 arcsec thereby subsampling the PSF. Dubbed HEXITEC, for High Energy X-Ray Imaging Technology, this Application Specific Integrated Circuit (ASIC), can be bonded to 1- or 2- mm-thick Cadmium Telluride (CdTe) or Cadmium-Zinc-Telluride (CZT) which provide high efficiency in the HXR region, good energy resolution, low background, low power, and low sensitivity to radiation damage. For solar observations, the ability to handle high counting rates is also extremely desirable. This ASIC can read each pixel 10,000 times per second. The NASA Marshall Space Flight Center (MSFC) and the Goddard Space Flight Center (GSFC) has been working with RAL over the past few years to develop these detectors to be used with HXR focusing telescopes. We present recent progress on this development effort and its capabilities as applied to solar observations.

  5. NADPH oxidase-mediated generation of reactive oxygen species: A new mechanism for X-ray-induced HeLa cell death

    SciTech Connect

    Liu Qing; He Xiaoqing; Liu Yongsheng; Du Bingbing; Wang Xiaoyan; Zhang Weisheng; Jia Pengfei; Dong Jingmei; Ma Jianxiu; Wang Xiaohu; Li Sha; Zhang Hong

    2008-12-19

    Oxidative damage is an important mechanism in X-ray-induced cell death. Radiolysis of water molecules is a source of reactive oxygen species (ROS) that contribute to X-ray-induced cell death. In this study, we showed by ROS detection and a cell survival assay that NADPH oxidase has a very important role in X-ray-induced cell death. Under X-ray irradiation, the upregulation of the expression of NADPH oxidase membrane subunit gp91{sup phox} was dose-dependent. Meanwhile, the cytoplasmic subunit p47{sup phox} was translocated to the cell membrane and localized with p22{sup phox} and gp91{sup phox} to form reactive NADPH oxidase. Our data suggest, for the first time, that NADPH oxidase-mediated generation of ROS is an important contributor to X-ray-induced cell death. This suggests a new target for combined gene transfer and radiotherapy.

  6. (Cd,Mn)Te detectors for characterization of x-ray emissions generated during laser-driven fusion experiments

    SciTech Connect

    Cross,A.S.; Knauer, J. P.; Mycielski, A.; Kochanowska, D.; Wiktowska-Baran, M.; Jakiela, R.; Domagala, J.; Cui, Y.; James, R.; Sobolewski, R.

    2008-10-19

    We present our measurements of (Cd,Mn)Te photoconductive detectors (PCDs), fabricated for the goal of measuring both the temporal and spectral dependences of X-ray emissions generated from laser-illuminated targets during the inertial confinement fusion experiments. Our Cd{sub 1-x}Mn{sub x}Te (x = 0.05) single crystals, doped with V, were grown using a vertical Bridgman method and, subsequently, annealed in Cd for the highest resistivity ({approx}10{sup 10} {Omega}cm) and a good mobility-lifetime product ({approx}10{sup -3} cm{sup 2}/V). The 1-mm- and 2.3-mm-thick detectors were placed in the same housing as two 1-mm-thick diamond PCDs. All devices were pre-screened by a 7.6-mm-thick Be X-ray filter with a frequency cutoff of 1 keV. The incident shots from the OMEGA laser were 1-ns-long square pulses with energies ranging from 2.3 kJ to 22.6 kJ, and the PCDs were biased with 5000 V/cm. The response amplitudes and rise times of our (Cd,Mn)Te PCDs were comparable with the diamond detector performance, while the decay times were 4 to 10 times longer and in the 2-5 ns range. We observed two X-ray emission events separated by 1.24 ns. The first was identified as caused by heating of the target and creating a hot corona, while the second one was from the resulting compressed core. For comparison purposes, our testing was performed using {approx}1 keV X-ray photons, optimal for the diamond PCD. According to the presented simulations, however, at X-ray energies >10 keV diamond absorption efficiency drops to <50%, whereas for (Cd,Mn)Te the drop occurs at {approx}100 keV with near perfect, 100% absorption, up to 50 keV.

  7. Evidence for nanoparticles in microwave-generated fireballs observed by synchrotron x-ray scattering.

    PubMed

    Mitchell, J B A; LeGarrec, J L; Sztucki, M; Narayanan, T; Dikhtyar, V; Jerby, E

    2008-02-15

    The small-angle x-ray scattering method has been applied to study fireballs ejected into the air from molten hot spots in borosilicate glass by localized microwaves [V. Dikhtyar and E. Jerby, Phys. Rev. Lett. 96 045002 (2006)10.1103/PhysRevLett.96.045002]. The fireball's particle size distribution, density, and decay rate in atmospheric pressure were measured. The results show that the fireballs contain particles with a mean size of approximately 50 nm with average number densities on the order of approximately 10(9). Hence, fireballs can be considered as a dusty plasma which consists of an ensemble of charged nanoparticles in the plasma volume. This finding is likened to the ball-lightning phenomenon explained by the formation of an oxidizing particle network liberated by lightning striking the ground [J. Abrahamson and J. Dinniss, Nature (London) 403, 519 (2000)10.1038/35000525].

  8. Evidence for Nanoparticles in Microwave-Generated Fireballs Observed by Synchrotron X-Ray Scattering

    SciTech Connect

    Mitchell, J. B. A.; Le Garrec, J. L.; Sztucki, M.; Narayanan, T.; Dikhtyar, V.; Jerby, E.

    2008-02-15

    The small-angle x-ray scattering method has been applied to study fireballs ejected into the air from molten hot spots in borosilicate glass by localized microwaves [V. Dikhtyar and E. Jerby, Phys. Rev. Lett. 96 045002 (2006)]. The fireball's particle size distribution, density, and decay rate in atmospheric pressure were measured. The results show that the fireballs contain particles with a mean size of {approx}50 nm with average number densities on the order of {approx}10{sup 9}. Hence, fireballs can be considered as a dusty plasma which consists of an ensemble of charged nanoparticles in the plasma volume. This finding is likened to the ball-lightning phenomenon explained by the formation of an oxidizing particle network liberated by lightning striking the ground [J. Abrahamson and J. Dinniss, Nature (London) 403, 519 (2000)].

  9. Evidence for Nanoparticles in Microwave-Generated Fireballs Observed by Synchrotron X-Ray Scattering

    NASA Astrophysics Data System (ADS)

    Mitchell, J. B. A.; Legarrec, J. L.; Sztucki, M.; Narayanan, T.; Dikhtyar, V.; Jerby, E.

    2008-02-01

    The small-angle x-ray scattering method has been applied to study fireballs ejected into the air from molten hot spots in borosilicate glass by localized microwaves [V. Dikhtyar and E. Jerby, Phys. Rev. Lett.PRLTAO0031-9007 96 045002 (2006)10.1103/PhysRevLett.96.045002]. The fireball’s particle size distribution, density, and decay rate in atmospheric pressure were measured. The results show that the fireballs contain particles with a mean size of ˜50nm with average number densities on the order of ˜109. Hence, fireballs can be considered as a dusty plasma which consists of an ensemble of charged nanoparticles in the plasma volume. This finding is likened to the ball-lightning phenomenon explained by the formation of an oxidizing particle network liberated by lightning striking the ground [J. Abrahamson and J. Dinniss, Nature (London)NATUAS0028-0836 403, 519 (2000)10.1038/35000525].

  10. Supersonic Heat Wave Propagation in Laser-Produced Underdense Plasma for Efficient X-Ray Generation

    SciTech Connect

    Tanabe, M; Nishimura, H; Fujioka, S; Nagai, K; Iwamae, A; Ohnishi, N; Fournier, K B; Girard, F; Primout, M; Villette, B; Tobin, M; Mima, K

    2008-06-12

    We have observed supersonic heat wave propagation in a low-density aerogel target ({rho} {approx} 3.2 mg/cc) irradiated at the intensity of 4 x 10{sup 14} W/cm{sup 2}. The heat wave propagation was measured with a time-resolved x-ray imaging diagnostics, and the results were compared with simulations made with the two-dimensional radiation-hydrodynamic code, RAICHO. Propagation velocity of the ionization front gradually decreased as the wave propagates into the target. The reason of decrease is due to increase of laser absorption region as the front propagates and interplay of hydrodynamic motion and reflection of laser propagation. These features are well reported with the simulation.

  11. Generation of X-rays and neutrons with a RF-discharge

    NASA Technical Reports Server (NTRS)

    Schneider, R. T.

    1982-01-01

    An experimental study concerning disk shaped plasma structures was performed. Such disk-shaped structures can be obtained using an rf discharge in hydrogen. The applied frequency was 1-2 Mhz. In case of operation in deuterium it was found that the discharge emits neutrons and X-rays, although the applied voltage is only 2 kV. This phenomenon was explained by assuming formation of plasma cavitons which are surrounded by high electric fields. The condition for formation of these cavitons is that the applied rf frequency is equal to the plasma frequency. The ions trapped in these resonance structures acquire sufficient energy that they can undergo fusion reactions with the ions in the surrounding gas.

  12. The X-ray emission of solar flares generated by anisotropic electron beams

    NASA Astrophysics Data System (ADS)

    Bogovalov, S. V.; Kelner, S. R.; Kotov, Y. D.

    1987-12-01

    For three types of the initial angle distribution of fast electrons, energy spectra, directivity, and polarization of the bremsstrahlung have been computed with an account for multiple scattering and energy losses. The influence of Compton scattering and of photoabsorption on the observed hard X-ray emission of solar flares has been investigated. It is obtained that the photon spectrum index depends not only on the spectrum of electrons but also on the registered energy range and on the angle of view of the flare. In the 10 - 40 keV range the spectrum is softer at the limb than in the solar disc centre; in the 60 - 360 keV the situation is reverse, the spectrum being softer in the solar disc centre.

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

    NASA Astrophysics Data System (ADS)

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

    2014-07-01

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

  14. Testing quantum mechanics in non-Minkowski space-time with high power lasers and 4th generation light sources

    PubMed Central

    Crowley, B. J. B.; Bingham, R.; Evans, R. G.; Gericke, D. O.; Landen, O. L.; Murphy, C. D.; Norreys, P. A.; Rose, S. J.; Tschentscher, Th; Wang, C. H.-T; Wark, J. S.; Gregori, G.

    2012-01-01

    A common misperception of quantum gravity is that it requires accessing energies up to the Planck scale of 1019 GeV, which is unattainable from any conceivable particle collider. Thanks to the development of ultra-high intensity optical lasers, very large accelerations can be now the reached at their focal spot, thus mimicking, by virtue of the equivalence principle, a non Minkowski space-time. Here we derive a semiclassical extension of quantum mechanics that applies to different metrics, but under the assumption of weak gravity. We use our results to show that Thomson scattering of photons by uniformly accelerated electrons predicts an observable effect depending upon acceleration and local metric. In the laboratory frame, a broadening of the Thomson scattered x ray light from a fourth generation light source can be used to detect the modification of the metric associated to electrons accelerated in the field of a high power optical laser. PMID:22768381

  15. MARS-a project of the diffraction-limited fourth generation X-ray source based on supermicrotron

    NASA Astrophysics Data System (ADS)

    Kulipanov, G. N.; Skrinsky, A. N.; Vinokurov, N. A.

    2001-07-01

    The new approach for the fourth generation X-ray source-Multiturn Accelerator-Recuperator Source (MARS)-was proposed recently. The installation consists of the radiofrequency (RF) multiturn accelerator (similar to the race-track microtron) and long undulator(s). After passing through the undulator(s) the electron beam is decelerated in the same RF accelerating structure. Such energy recovery reduces dramatically the radiation hazard and decreases the required RF power. In this paper we present a more detail explanation of this scheme, and specify further the parameter limitations and requirements for the accelerator.

  16. In-pixel conversion with a 10 bit SAR ADC for next generation X-ray FELs

    NASA Astrophysics Data System (ADS)

    Lodola, L.; Batignani, G.; Benkechkache, M. A.; Bettarini, S.; Casarosa, G.; Comotti, D.; Dalla Betta, G. F.; Fabris, L.; Forti, F.; Grassi, M.; Latreche, S.; Malcovati, P.; Manghisoni, M.; Mendicino, R.; Morsani, F.; Paladino, A.; Pancheri, L.; Paoloni, E.; Ratti, L.; Re, V.; Rizzo, G.; Traversi, G.; Vacchi, C.; Verzellesi, G.; Xu, H.

    2016-07-01

    This work presents the design of an interleaved Successive Approximation Register (SAR) ADC, part of the readout channel for the PixFEL detector. The PixFEL project aims at substantially advancing the state-of-the-art in the field of 2D X-ray imaging for applications at the next generation Free Electron Laser (FEL) facilities. For this purpose, the collaboration is developing the fundamental microelectronic building blocks for the readout channel. This work focuses on the design of the ADC carried out in a 65 nm CMOS technology. To obtain a good tradeoff between power consumption, conversion speed and area occupation, an interleaved SAR ADC architecture was adopted.

  17. Research and development of an electron beam focusing system for a high-brightness X-ray generator.

    PubMed

    Sakai, Takeshi; Ohsawa, Satoshi; Sakabe, Noriyoshi; Sugimura, Takashi; Ikeda, Mitsuo

    2011-01-01

    A new type of rotating anticathode X-ray generator, where an electron beam of up to 60 keV irradiates the inner surface of a U-shaped Cu anticathode, has achieved a beam brilliance of 130 kW mm(-2) (at 2.3 kW). A higher-flux electron beam is expected from simulation by optimizing the geometry of a combined-function-type magnet instead of the fringing field of the bending magnet. In order to minimize the size of the X-ray source the electron beam has been focused over a short distance by a new combined-function bending magnet, whose geometrical shape was determined by simulation using the Opera-3D, General Particle Tracer and CST-STUDIO codes. The result of the simulation clearly shows that the role of combined functions in both the bending and the steering magnets is important for focusing the beam to a small size. FWHM sizes of the beam are predicted by simulation to be 0.45 mm (horizontal) and 0.05 mm (vertical) for a 120 keV/75 mA beam, of which the effective brilliance is about 500 kW mm(-2) on the supposition of a two-dimensional Gaussian distribution. High-power tests have begun using a high-voltage 120 kV/75 mA power supply for the X-ray generator instead of 60 kV/100 mA. The beam focus size on the target will be verified in the experiments.

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

    NASA Astrophysics Data System (ADS)

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

    2015-01-01

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

  19. EIGER: Next generation single photon counting detector for X-ray applications

    NASA Astrophysics Data System (ADS)

    Dinapoli, Roberto; Bergamaschi, Anna; Henrich, Beat; Horisberger, Roland; Johnson, Ian; Mozzanica, Aldo; Schmid, Elmar; Schmitt, Bernd; Schreiber, Akos; Shi, Xintian; Theidel, Gerd

    2011-09-01

    EIGER is an advanced family of single photon counting hybrid pixel detectors, primarily aimed at diffraction experiments at synchrotrons. Optimization of maximal functionality and minimal pixel size (using a 0.25 μm process and conserving the radiation tolerant design) has resulted in 75×75 μm2 pixels. Every pixel comprises a preamplifier, shaper, discriminator (with a 6 bit DAC for threshold trimming), a configurable 4/8/12 bit counter with double buffering, as well as readout, control and test circuitry. A novel feature of this chip is its double buffered counter, meaning a next frame can be acquired while the previous one is being readout. An array of 256×256 pixels fits on a ˜2×2 cm2 chip and a sensor of ˜8×4 cm2 will be equipped with eight readout chips to form a module containing 0.5 Mpixel. Several modules can then be tiled to form larger area detectors. Detectors up to 4×8 modules (16 Mpixel) are planned. To achieve frame rates of up to 24 kHz the readout architecture is highly parallel, and the chip readout happens in parallel on 32 readout lines with a 100 MHz Double Data Rate clock. Several chips and singles (i.e. a single chip bump-bonded to a single chip silicon sensor) were tested both with a lab X-ray source and at Swiss Light Source (SLS) beamlines. These tests demonstrate the full functionality of the chip and provide a first assessment of its performance. High resolution X-ray images and "high speed movies" were produced, even without threshold trimming, at the target system frame rates (up to ˜24 kHz in 4 bit mode). In parallel, dedicated hardware, firmware and software had to be developed to comply with the enormous data rate the chip is capable of delivering. Details of the chip design and tests will be given, as well as highlights of both test and final readout systems.

  20. Rare decays of the Z and the standard model, 4th generation, and beyond

    SciTech Connect

    Weiler, T.J.

    1989-01-01

    Several issues in rare decays of the Z are addressed. The rate for flavor-changing Z decay grows as the fourth power of the fermion masses internal to the quantum loop, and so offers a window to the existence of ultraheavy (m > M{sub W}) fermions. In the standard model, with three generations, BR(Z {yields} bs) < 10{sup -7} and BR(Z{yields}tc)<10{sup -13}. With four generations, BR(Z {yields} bb{sub 4}) may be as large as 10{sup -5} if m{sub b4} < M{sub Z}; and similarly for BR(Z {yields} N{sub 4}v), where N{sub 4} is the possibly heavy fourth generation neutrino. In supersymmetric and other two Higgs doublet models, BR(Z {yields} tc) may be as large as 5 {times} 10{sup -6} in the three generation scheme. With minimal supersymmetry, the reaction Z {yields} H{gamma} is guaranteed to go, with a parameter-dependent branching ratio of 10{sup -6 {plus minus} 3}. With mirror fermions or exotic E{sub 6} fermions, the branching ratios for Z {yields} ct (70 GeV), Z {yields} {mu}{tau}, and Z {yields} bb{sub 4} (70 GeV) are typically 10{sup -4}, 10{sup -4}, and 10{sup -3} respectively, clearly measurable at LEP. Depending on unknown quark masses, the Z may mix with vector (b{sub 4}{bar b}{sub 4}) and the W may mix with vector (t{bar b}) or (t{bar s}). CP violating asymmetries in flavor-changing Z decay are immeasurably small in the standard model, but may be large in supersymmetric and other nonstandard models. 28 refs.

  1. Battling the "Hydra": Changing Operational Factors in 4th Generation War

    DTIC Science & Technology

    2007-11-02

    challenging us to change current doctrine and attempts to reduce war to algebraic formulae. Current Operational Doctrine Operational art, as advanced...over terrain -- the image and concept of ’classic’ war. A- 2 Armies turned to ’science," relying upon mathematical probabilities and algebraic formulae...Jominian war of algebraic formula and mathematical probabilities, vice accepting the 3d generation premise to cause and thrive within chaos. Lacking

  2. Laser plasma cryogenic target on translating substrate for generation of continuously repetitive EUV and soft X-ray pulses.

    PubMed

    Amano, Sho

    2014-06-01

    To generate continuously repetitive EUV and soft X-ray pulses with various wavelengths from laser-produced plasmas, a one-dimensionally translating substrate system with a closed He gas cryostat that can continuously supply various cryogenic targets for ~10 Hz laser pulses has been developed. The system was successfully operated at a lowest temperature of 15 K and at a maximum up-down speed of 12 mm/s. Solid Ar, Kr, and Xe layers were formed, and their growth rates and the laser crater sizes on them were studied. By optimization of the operational parameters in accordance with our design rule, it was shown that stable output power was achieved continuously from the plasma emission at frequencies of 1-10 Hz. The average soft X-ray and EUV powers obtained were 19 mW at 3.2 nm, 33 mW at 10.0 nm, and 66 mW at 10.8 nm, with 10% bandwidths, from the Ar, Kr, and Xe solid targets, respectively, with a laser power of 1 W. We will be able to achieve higher frequencies using a high beam quality laser that produces smaller craters, and can expect higher powers. Although only Ar, Kr, and Xe gases were tested in this study, the target system achieved a temperature of 15 K and can thus solidify almost all target gases, apart from H and He, and can continuously supply the solid target. The use of various target materials will enable expansion of the EUV and soft X-ray emission wavelength range.

  3. Efficient multi-keV x-ray source generated by nanosecond laser pulse irradiated multi-layer thin foils target

    SciTech Connect

    Tu, Shao-yong; Hu, Guang-yue Zhao, Bin; Zheng, Jian; Miao, Wen-yong; Yuan, Yong-teng; Zhan, Xia-yu; Hou, Li-fei; Jiang, Shao-en; Ding, Yong-kun

    2014-04-15

    A new target configuration is proposed to generate efficient multi-keV x-ray source using multiple thin foils as x-ray emitters. The target was constructed with several layers of thin foils, which were placed with a specific, optimized spacing. The thin foils are burned though one by one by a nanosecond-long laser pulse, which produced a very large, hot, underdense plasma. One-dimensional radiation hydrodynamic simulations show that the emission region and the multi-keV x-ray flux generated by multi-layer thin foil target are similar to that of the low-density gas or foam target, which is currently a bright multi-keV x-ray source generated by laser heating. Detailed analysis of a range of foil thicknesses showed that a layer-thickness of 0.1 μm is thin enough to generate an efficient multi-keV x-ray source. Additionally, this type of target can be easily manufactured, compared with the complex techniques for fabrication of low-density foam targets. Our preliminary experimental results also verified that the size of multi-keV x-ray emission region could be enhanced significantly by using a multi-layer Ti thin foil target.

  4. The development and characterization of a first generation carbon nanotube x-ray based microbeam radiation therapy system

    NASA Astrophysics Data System (ADS)

    Hadsell, Michael John, Jr.

    Microbeam radiation therapy (MRT) is a new type of cancer treatment currently being studied at scattered synchrotron sites throughout the world. It has been shown to be capable of ablating aggressive brain tumors in rats while almost completely sparing the surrounding normal tissue. This promising technique has yet to find its way to the clinic, however, because the radiobiological mechanisms behind its efficacy are still largely unknown. This is partly due to the lack of a compact device that could facilitate more large scale research. The challenges inherent to creating a compact device lie within the structure of MRT, which uses parallel arrays of ultra high-dose, orthovoltage, microplanar beams on the order of 100mum thick and separated by four to ten times their width. Because of focal spot limitations, current commercial orthovoltage devices are simply not capable of creating such arrays at dose rates high enough for effective treatment while maintaining the microbeam pattern necessary to retain the high therapeutic ratio of the technique. Therefore, the development of a compact MRT device using carbon nanotube (CNT) cathode based X-ray technology is presented here. CNT cathodes have been shown to be capable of creating novel focal spot arrays on a single anode while being robust enough for long-term use in X-ray tubes. Using these cathodes, an X-ray tube with a single focal line has been created for the delivery of MRT dose distributions in radiobiological studies on small animals. In this work, the development process and final design of this specialized device will be detailed, along with the optimization and stabilization of its use for small animal studies. In addition, a detailed characterization of its final capabilities will be given; including a comprehensive measurement of its X-ray focal line dimensions, a description and evaluation of its collimator alignment and microbeam dimensions, and a full-scale phantom-based quantification of its dosimetric

  5. Generation of a coherent x ray in the water window region at 1 kHz repetition rate using a mid-infrared pump source.

    PubMed

    Xiong, Hui; Xu, Han; Fu, Yuxi; Yao, Jinping; Zeng, Bin; Chu, Wei; Cheng, Ya; Xu, Zhizhan; Takahashi, Eiji J; Midorikawa, Katsumi; Liu, X; Chen, J

    2009-06-01

    We demonstrate the generation of a coherent x ray in the water window region in a gas cell filled with neon gas using a wavelength-tunable mid-IR femtosecond laser operating at 1 kHz repetition rate. The cutoff energy and conversion efficiency of the water window x ray can be optimized by tuning gas pressure as well as the focal position.

  6. High Flux Spatially Coherent X-ray Generation from Laser Wakefield Accelerators

    NASA Astrophysics Data System (ADS)

    McGuffey, Chris

    2011-10-01

    Nonlinear plasma waves driven by existing ultra-intense short-pulse lasers can trap large numbers of electrons from the plasma (as many as 5 ×109) and accelerate them to ~ GeV energy over ~ 1 cm . The details of the trapping process and plasma wave structure dictate that the trapped electrons undergo transverse oscillatory motion on the microscopic scale of the plasma structure, resulting in short wavelength betatron radiation. These x-ray beams are presumed to retain the short-pulse characteristic of the laser, resulting in high peak flux, making the source a candidate for ultrafast temporally resolved imaging applications. Presented here are experimental studies of the scalings of fluence upon laser power, gas jet length, and electron beam parameters. The spectrum was directly measured by single hit spectroscopy to be broad and smooth with peak photon energy exceeding 10 keV . Additional measurements indicate that the beam source size can be as small as 1 μm and that the radiation exhibits spatial coherence. These two key characteristics allow advanced imaging capabilities including phase contrast imaging and tomography, as demonstrated by radiography studies of biological specimens. Collaborators: S. Kneip (Imperial College London), T. Matsuoka (Present affiliation: Japan Aerospace Exploration Agency, Institute of Space and Astronautical Science), W. Schumaker, V. Chvykov, F. Dollar, M. Vargas, G. Kalintchenko, V. Yanovsky, A. Maksimchuk, A. G. R. Thomas, and K. Krushelnick (University of Michigan). This work was supported by the NSF (award PHY-0114336), the NSF/DNDO (award F021166), and the NRC (award 38-09-953).

  7. Route to optimal generation of soft X-ray high harmonics with synthesized two-color laser pulses

    PubMed Central

    Jin, Cheng; Wang, Guoli; Le, Anh-Thu; Lin, C. D.

    2014-01-01

    High harmonics extending to X-rays have been generated from gases by intense lasers. To establish these coherent broadband radiations as an all-purpose tabletop light source for general applications in science and technology, new methods are needed to overcome the present low conversion efficiencies. Here we show that the conversion efficiency may be drastically increased with an optimized two-color pulse. By employing an optimally synthesized 2-µm mid-infrared laser and a small amount of its third harmonic, we show that harmonic yields from sub- to few-keV energy can be increased typically by ten-fold over the optimized single-color one. By combining with favorable phase-matching and together with the emerging high-repetition MHz mid-infrared lasers, we anticipate efficiency of harmonic yields can be increased by four to five orders in the near future, thus paving the way for employing high harmonics as useful broadband tabletop light sources from the extreme ultraviolet to the X-rays, as well as providing new tools for interrogating ultrafast dynamics of matter at attosecond timescales. PMID:25400015

  8. Interfacial Restructuring of Ionic Liquids Determined by Sum-Frequency Generation Spectroscopy and X-ray Reflectivity

    SciTech Connect

    Jeon, Yoonnam; Sung, Jaeho; Bu, Wei; Vaknin, David; Ouchi, Yukio; Kim, Doseok

    2009-01-16

    Surface sum-frequency generation spectroscopy and X-ray reflectivity were used to study the surface of [BMIM][X] ionic liquids (BMIM = 1-butyl-3-methylimidazolium cation, X = BF{sub 4}{sup -}, PF{sub 6}{sup -}, and I{sup -}). Sum-frequency signal strength from the terminal methyl groups of the cation at the surface indicates that the topmost surface of these ionic liquids is occupied by polar-oriented hydrophobic butyl chains having approximately 1/3 of the in-plane density of fully packed alkyl chains as observed by the same method for the hexadecanol Langmuir monolayer. X-ray reflectivity data reveal a layer with density larger than that of bulk. However, the reflectivity is not sufficiently sensitive to the exact location of this layer either at the vacuum interface or sandwiched between the bulk and the low-density alkyl chain, as observed in the sum-frequency measurements. Analysis of the reflectivity data in conjunction with the sum-frequency spectra strongly suggests the molecules forming the topmost layer are on average polar-oriented with their (loosely packed) butyl chains toward the gas/liquid interface, while the (densely packed) imidazolium cores/anions are in contact with the bulk liquid.

  9. CHARACTERIZATION OF SALT PARTICLE INDUCED CORROSION PROCESSES BY SYNCHROTRON GENERATED X-RAY FLUORESCENCE AND COMPLEMENTARY SURFACE ANALYSIS TOOLS.

    SciTech Connect

    NEUFELD, A.K.; COLE, I.S.; BOND, A.M.; ISAACS, H.S.; FURMAN, S.A.

    2001-03-25

    The benefits of using synchrotron-generated X-rays and X-ray fluorescence analysis in combination with other surface analysis techniques have been demonstrated. In studies of salt-induced corrosion, for example, the detection of Rb ions in the area of secondary spreading when salt-containing micro-droplets are placed on zinc surfaces, further supports a mechanism involving cation transport during the corrosion and spreading of corrosive salt on exposed metal surfaces. Specifically, the new analytical data shows that: (a) cations are transported radially from a primary drop formed from a salt deposit in a thin film of secondary spreading around the drop; (b) subsequently, micro-pools are formed in the area of secondary spreading, and it is likely that cations transported within the thin film accumulate in these micro-pools until the area is dehydrated; (c) the mechanism of cation transport into the area of secondary spreading does not include transport of the anions; and (d) hydroxide is the counter ion formed from oxygen reduction at the metal surface within the spreading layer. Data relevant to iron corrosion is also presented and the distinct differences relative to the zinc situation are discussed.

  10. Focusing X-Ray Telescopes

    NASA Technical Reports Server (NTRS)

    O'Dell, Stephen; Brissenden, Roger; Davis, William; Elsner, Ronald; Elvis, Martin; Freeman, Mark; Gaetz, Terrance; Gorenstein, Paul; Gubarev, Mikhall; Jerlus, Diab; Juda, Michael; Kolodziejczak, Jeffrey; Murray, Stephen; Petre, Robert; Podgorski, William; Ramsey, Brian; Reid, Paul; Saha, Timo; Wolk, Scott; Troller-McKinstry, Susan; Weisskopf, Martin; Wilke, Rudeger; Zhang, William

    2010-01-01

    During the half-century history of x-ray astronomy, focusing x-ray telescopes, through increased effective area and finer angular resolution, have improved sensitivity by 8 orders of magnitude. Here, we review previous and current x-ray-telescope missions. Next, we describe the planned next-generation x-ray-astronomy facility, the International X-ray Observatory (IXO). We conclude with an overview of a concept for the next next-generation facility, Generation X. Its scientific objectives will require very large areas (about 10,000 sq m) of highly-nested, lightweight grazing-incidence mirrors, with exceptional (about 0.1-arcsec) resolution. Achieving this angular resolution with lightweight mirrors will likely require on-orbit adjustment of alignment and figure.

  11. In operando x-ray tomography for next-generation batteries: a systematic approach to monitor reaction product distribution and transport processes

    NASA Astrophysics Data System (ADS)

    Schröder, D.; Bender, C. L.; Arlt, T.; Osenberg, M.; Hilger, A.; Risse, S.; Ballauff, M.; Manke, I.; Janek, J.

    2016-10-01

    Computed tomography with x-rays is a powerful tool to analyze the complex reaction and transport processes that occur inside electrochemical storage devices. To this day, a better insight into the occurring processes is needed and will yield improvements in energy density and cycling stability of next-generation batteries. Herein we present general considerations for the use of x-ray tomography of batteries to gain a detailed insight during operation. Furthermore, we present examples for the tomography of zinc-oxygen batteries, sodium-oxygen batteries and metal-sulfur batteries, elucidating performance limiting degradation processes such as dendrite formation and loss of liquid electrolyte. With the method applied, we aim to establish an effective link between the battery and x-ray community by offering a guideline on how to apply x-ray tomography to propel research on battery materials and entire batteries.

  12. X-ray and runaway electron generation in repetitive pulsed discharges in atmospheric pressure air with a point-to-plane gap

    SciTech Connect

    Shao Tao; Yan Ping; Tarasenko, Victor F.; Shut'ko, Yuliya V.; Zhang Cheng

    2011-05-15

    In this paper, using two repetitive nanosecond generators, x-rays were detected in atmospheric air with a highly inhomogeneous electric field by a point-to- plane gap. The rise times of the generators were about 15 and 1 ns. The x-rays were directly measured by various dosimeters and a NaI scintillator with a photomultiplier tube. X-rays were detected in the continuous mode at pulse repetition frequency up to 1 kHz and a voltage pulse rise time of {approx}15 ns. It is shown that the maximum x-ray intensity is attainable at different pulse repetition frequencies depending on the voltage pulse parameters and cathode design. In atmospheric pressure air the x-ray intensity is found to increase with increasing the pulse repetition frequency up to 1 kHz. It is confirmed that the maximum x-ray intensity is attained in a diffuse discharge in a point-to-plane gap.

  13. Inner-Shell Photon-Ionized X-Ray Laser at 45(Angstrom)

    SciTech Connect

    Weber, F; Celliers, P; Moon, S; Snavely, R; Da Silva, L

    2002-02-01

    This report summarizes the major accomplishments of this three-year Laboratory Directed Research and Development (LDRD) Lab Wide (LW) project entitled, ''An Inner-Shell Photo-Ionized X-Ray Laser at 45 {angstrom}'', tracking code 99-LW-042. The most significant accomplishments of this project include the design of a suitable x-ray laser target, the invention of a measurement technique for the determination of rise times of x-ray pulses on the order of 50 femtoseconds, and a novel setup for generating a traveling wave with an ultrashort optical laser pulse. The pump probe technique for rise time measurement will allow us to detect ultrashort x-ray pulses, whose generation by means of a variety of 4th generation light sources is currently under planning elsewhere.

  14. Compact x-ray source and panel

    SciTech Connect

    Sampayon, Stephen E.

    2008-02-12

    A compact, self-contained x-ray source, and a compact x-ray source panel having a plurality of such x-ray sources arranged in a preferably broad-area pixelized array. Each x-ray source includes an electron source for producing an electron beam, an x-ray conversion target, and a multilayer insulator separating the electron source and the x-ray conversion target from each other. The multi-layer insulator preferably has a cylindrical configuration with a plurality of alternating insulator and conductor layers surrounding an acceleration channel leading from the electron source to the x-ray conversion target. A power source is connected to each x-ray source of the array to produce an accelerating gradient between the electron source and x-ray conversion target in any one or more of the x-ray sources independent of other x-ray sources in the array, so as to accelerate an electron beam towards the x-ray conversion target. The multilayer insulator enables relatively short separation distances between the electron source and the x-ray conversion target so that a thin panel is possible for compactness. This is due to the ability of the plurality of alternating insulator and conductor layers of the multilayer insulators to resist surface flashover when sufficiently high acceleration energies necessary for x-ray generation are supplied by the power source to the x-ray sources.

  15. Cosmic x ray physics

    NASA Technical Reports Server (NTRS)

    Mccammon, Dan; Cox, D. P.; Kraushaar, W. L.; Sanders, W. T.

    1990-01-01

    The annual progress report on Cosmic X Ray Physics is presented. Topics studied include: the soft x ray background, proportional counter and filter calibrations, the new sounding rocket payload: X Ray Calorimeter, and theoretical studies.

  16. Cosmic x ray physics

    NASA Technical Reports Server (NTRS)

    Mccammon, Dan; Cox, D. P.; Kraushaar, W. L.; Sanders, W. T.

    1991-01-01

    The annual progress report on Cosmic X Ray Physics for the period 1 Jan. to 31 Dec. 1990 is presented. Topics studied include: soft x ray background, new sounding rocket payload: x ray calorimeter, and theoretical studies.

  17. Chest X-Ray

    MedlinePlus

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

  18. Joint x-ray

    MedlinePlus

    X-ray - joint; Arthrography; Arthrogram ... x-ray technologist will help you position the joint to be x-rayed on the table. Once in place, pictures are taken. The joint may be moved into other positions for more ...

  19. Generation of high-photon flux-coherent soft x-ray radiation with few-cycle pulses.

    PubMed

    Demmler, Stefan; Rothhardt, Jan; Hädrich, Steffen; Krebs, Manuel; Hage, Arvid; Limpert, Jens; Tünnermann, Andreas

    2013-12-01

    We present a tabletop source of coherent soft x-ray radiation with high-photon flux. Two-cycle pulses delivered by a fiber-laser-pumped optical parametric chirped-pulse amplifier operating at 180 kHz repetition rate are upconverted via high harmonic generation in neon to photon energies beyond 200 eV. A maximum photon flux of 1.3·10(8) photons/s is achieved within a 1% bandwidth at 125 eV photon energy. This corresponds to a conversion efficiency of ~10(-9), which can be reached due to a gas jet simultaneously providing a high target density and phase matching. Further scaling potential toward higher photon flux as well as higher photon energies are discussed.

  20. Submicrometre beams from a hard X-ray waveguide at a third-generation synchrotron radiation source.

    PubMed

    Cedola, A; Lagomarsino, S; Di Fonzo, S; Jark, W; Riekel, C; Deschamps, P

    1998-01-01

    The use of an X-ray waveguide for scattering experiments at an undulator of a third-generation synchrotron radiation source is discussed. The performance with a perfect crystal monochromator, multilayer monochromator and focusing mirror is explored. A maximum flux of 8 x 109 photons s(-1) at lambda = 0.083 nm was obtained for a 0.15 (V) x 600 (H) micron(2) beam at the exit of the waveguide with a multilayer monochromator. The combination of an Si (111) monochromator and ellipsoidal mirror resulted in a flux of approximately 10(9) photons s(-1) but with a horizontal compression of the beam to approximately 30 micron. The use of the waveguide in diffraction experiments is addressed.

  1. Generation and Propagation of a Picosecond Acoustic Pulse at a Buried Interface: Time-Resolved X-Ray Diffraction Measurements

    SciTech Connect

    Lee, S.H.; Cavalieri, A.L.; Fritz, D.M.; Swan, M.C.; Reis, D.A.; Hegde, R.S.; Reason, M.; Goldman, R.S.

    2005-12-09

    We report on the propagation of coherent acoustic wave packets in (001) surface oriented Al{sub 0.3}Ga{sub 0.7}As/GaAs heterostructure, generated through localized femtosecond photoexcitation of the GaAs. Transient structural changes in both the substrate and film are measured with picosecond time-resolved x-ray diffraction. The data indicate an elastic response consisting of unipolar compression pulses of a few hundred picosecond duration traveling along [001] and [001] directions that are produced by predominately impulsive stress. The transmission and reflection of the strain pulses are in agreement with an acoustic mismatch model of the heterostructure and free-space interfaces.

  2. Modular approach to achieving the next-generation X-ray light source

    NASA Astrophysics Data System (ADS)

    Biedron, S. G.; Milton, S. V.; Freund, H. P.

    2001-12-01

    A modular approach to the next-generation light source is described. The "modules" include photocathode, radio-frequency, electron guns and their associated drive-laser systems, linear accelerators, bunch-compression systems, seed laser systems, planar undulators, two-undulator harmonic generation schemes, high-gain harmonic generation systems, nonlinear higher harmonics, and wavelength shifting. These modules will be helpful in distributing the next-generation light source to many more laboratories than the current single-pass, high-gain free-electron laser designs permit, due to both monetary and/or physical space constraints.

  3. X-ray emission analysis of a plasma source using an yttrium and a mylar target for the generation of 2.48 nm wavelength microbeam

    NASA Astrophysics Data System (ADS)

    Palladino, Libero; Lorenzo, Ramon Gimenez De; Emilio, Maurizio Di Paolo; Limongi, Tania

    2013-05-01

    In this work, the characteristics of X-ray beam generated from a plasma produced by focusing a Nd-Yag/glass laser beam on mylar or yttrium target were presented. For each target material, the conversion efficiencies of the soft X-ray emission in two different energy ranges, (i) 300-510 eV (almost coincident with the Water Window), (ii) 450-850 eV were measured. The experimental results of the conversion efficiencies will be utilized at the PLASMA-X laboratory of L'Aquila University for the realization of an intense monochromatic X-ray microbeam to be used in radiobiological and in transmission X-ray microscopy applications. In the presented experimental set-up, at the wavelength of 2.48 nm, a monochromatic soft X-rays beam was collected by multilayer spherical mirrors reflecting at an incidence angle close to the normal of the surface. The optical system geometry, the monochromatic beam intensity and the measures of efficiency of conversion of X-ray were described in this paper [5].

  4. Organic semiconducting single crystals as next generation of low-cost, room-temperature electrical X-ray detectors.

    PubMed

    Fraboni, Beatrice; Ciavatti, Andrea; Merlo, Francesco; Pasquini, Luca; Cavallini, Anna; Quaranta, Alberto; Bonfiglio, Annalisa; Fraleoni-Morgera, Alessandro

    2012-05-02

    Direct, solid-state X-ray detectors based on organic single crystals are shown to operate at room temperature, in air, and at voltages as low as a few volts, delivering a stable and reproducible linear response to increasing X-ray dose rates, with notable radiation hardness and resistance to aging. All-organic and optically transparent devices are reported.

  5. X-Ray Diffraction Apparatus

    NASA Technical Reports Server (NTRS)

    Blake, David F. (Inventor); Bryson, Charles (Inventor); Freund, Friedmann (Inventor)

    1996-01-01

    An x-ray diffraction apparatus for use in analyzing the x-ray diffraction pattern of a sample is introduced. The apparatus includes a beam source for generating a collimated x-ray beam having one or more discrete x-ray energies, a holder for holding the sample to be analyzed in the path of the beam, and a charge-coupled device having an array of pixels for detecting, in one or more selected photon energy ranges, x-ray diffraction photons produced by irradiating such a sample with said beam. The CCD is coupled to an output unit which receives input information relating to the energies of photons striking each pixel in the CCD, and constructs the diffraction pattern of photons within a selected energy range striking the CCD.

  6. Absorbed dose-to-water protocol applied to synchrotron-generated x-rays at very high dose rates

    NASA Astrophysics Data System (ADS)

    Fournier, P.; Crosbie, J. C.; Cornelius, I.; Berkvens, P.; Donzelli, M.; Clavel, A. H.; Rosenfeld, A. B.; Petasecca, M.; Lerch, M. L. F.; Bräuer-Krisch, E.

    2016-07-01

    Microbeam radiation therapy (MRT) is a new radiation treatment modality in the pre-clinical stage of development at the ID17 Biomedical Beamline of the European synchrotron radiation facility (ESRF) in Grenoble, France. MRT exploits the dose volume effect that is made possible through the spatial fractionation of the high dose rate synchrotron-generated x-ray beam into an array of microbeams. As an important step towards the development of a dosimetry protocol for MRT, we have applied the International Atomic Energy Agency’s TRS 398 absorbed dose-to-water protocol to the synchrotron x-ray beam in the case of the broad beam irradiation geometry (i.e. prior to spatial fractionation into microbeams). The very high dose rates observed here mean the ion recombination correction factor, k s , is the most challenging to quantify of all the necessary corrections to apply for ionization chamber based absolute dosimetry. In the course of this study, we have developed a new method, the so called ‘current ramping’ method, to determine k s for the specific irradiation and filtering conditions typically utilized throughout the development of MRT. Using the new approach we deduced an ion recombination correction factor of 1.047 for the maximum ESRF storage ring current (200 mA) under typical beam spectral filtering conditions in MRT. MRT trials are currently underway with veterinary patients at the ESRF that require additional filtering, and we have estimated a correction factor of 1.025 for these filtration conditions for the same ESRF storage ring current. The protocol described herein provides reference dosimetry data for the associated Treatment Planning System utilized in the current veterinary trials and anticipated future human clinical trials.

  7. The PixFEL project: Progress towards a fine pitch X-ray imaging camera for next generation FEL facilities

    NASA Astrophysics Data System (ADS)

    Rizzo, G.; Batignani, G.; Benkechkache, M. A.; Bettarini, S.; Casarosa, G.; Comotti, D.; Dalla Betta, G.-F.; Fabris, L.; Forti, F.; Grassi, M.; Lodola, L.; Malcovati, P.; Manghisoni, M.; Mendicino, R.; Morsani, F.; Paladino, A.; Pancheri, L.; Paoloni, E.; Ratti, L.; Re, V.; Traversi, G.; Vacchi, C.; Verzellesi, G.; Xu, H.

    2016-07-01

    The INFN PixFEL project is developing the fundamental building blocks for a large area X-ray imaging camera to be deployed at next generation free electron laser (FEL) facilities with unprecedented intensity. Improvement in performance beyond the state of art in imaging instrumentation will be explored adopting advanced technologies like active edge sensors, a 65 nm node CMOS process and vertical integration. These are the key ingredients of the PixFEL project to realize a seamless large area focal plane instrument composed by a matrix of multilayer four-side buttable tiles. In order to minimize the dead area and reduce ambiguities in image reconstruction, a fine pitch active edge thick sensor is being optimized to cope with very high intensity photon flux, up to 104 photons per pixel, in the range from 1 to 10 keV. A low noise analog front-end channel with this wide dynamic range and a novel dynamic compression feature, together with a low power 10 bit analog to digital conversion up to 5 MHz, has been realized in a 110 μm pitch with a 65 nm CMOS process. Vertical interconnection of two CMOS tiers will be also explored in the future to build a four-side buttable readout chip with high density memories. In the long run the objective of the PixFEL project is to build a flexible X-ray imaging camera for operation both in burst mode, like at the European X-FEL, or in continuous mode with the high frame rates anticipated for future FEL facilities.

  8. Center for X-Ray Optics, 1986

    SciTech Connect

    Not Available

    1987-07-01

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

  9. Harmonic generation in VUV/x-ray range at the Duke storage ring FEL using electron beam outcoupling

    SciTech Connect

    Litvinenko, V.N.; Burnham, B.; Madey, J.M.J.

    1995-12-31

    We suggest using the OK-4 FEL operating in giant pulse mode to generate intracavity optical power at a level of hundreds of megawatts. These levels of power are sufficient to generate harmonics in the electron beam density. The prebunched electron beam then radiates coherently in an additional wiggler which is tuned on a harmonic of the OK-4 wavelength. The electron beam is turned by an achromatic bend into this wiggler, and harmonic radiation propagates with a small angle with respect to the OK-4 optical axis. This radiation will pass around the mirror of the OK-4 optical cavity and can then be utilized. This electron outcoupling scheme was suggested by N.A. Vinokurov as a method of optics independent outcoupling for high power FELs where electron beam bunching is provided in the master oscillator. This scheme is perfectly suited for optics independent harmonic generation. We suggest to operate the OK-4 FEL as a master oscillator in the UV range of 100 to 250 nm where conventional optics are available. This harmonic generation scheme would allow us to cover the VUV and soft X-Ray range with tunable coherent radiation. In this paper we present the possible layout of this system at the Duke storage ring and its expected operating parameters.

  10. X-ray FEL based on harmonics generation and electron beam outcoupling

    SciTech Connect

    Litvinenko, V.N.; Burnham, B.

    1995-12-31

    Electron beam outcoupling was suggested by N. A. Vinokurov as a method of optics independent outcoupling for high power FELs. The bunching of the electron beam is provided in a master oscillator. The prebunched electron beam then radiates coherently into an additional wiggler called the radiator. The electron beam is turned by an achromatic bend into this wiggler and its radiation propagates with a small angle with respect to the OK-4 optical axis. Thus, the radiation will pass around the mirror of the master oscillator optical cavity and can then be utilized. This scheme is perfectly suited for harmonic generation if the radiator wiggler is tuned on one of the master oscillator wavelength harmonics. This system is reminiscent of a klystron operating on a harmonic of the reference frequency. In this paper we present the theory of this device, its spectral and spatial characteristics of radiation, the optimization of the master oscillator, the achromatic bend and bunching for harmonic generation, and influence of beam parameters (energy spread, emittance, etc.) on generated power. Examples of possible storage ring and linac driven systems are discussed.

  11. Performance study of a soft X-ray harmonic generation FEL seededwith an EUV laser pulse

    SciTech Connect

    Gullans, M.; Wurtele, J.S.; Penn, G.; Zholents, A.A.

    2007-02-01

    The performance of a free electron laser (FEL) using alow-power extreme ultraviolet (EUV) pulse as an input seed isinvestigated. The parameters are appropriate for 30 nm seeds producedfrom high-power Ti:Sa pulses using high harmonic generation schemes. Itis found that, for reasonable beam parameters, robust FEL performance canbe obtained. Both time-independent and time-dependent simulations areperformed for varying system parameters using the GENESIS simulationcode. A comparison is made with a two-stage harmonic FEL that is seededby a high-power Ti:Sa pulse.

  12. Performance of a ruthenium beam separator used to separate soft x rays from light generated by a high-order harmonic light source.

    PubMed

    Ichimaru, Satoshi; Hatayama, Masatoshi; Ohchi, Tadayuki; Gullikson, Eric M; Oku, Satoshi

    2016-02-10

    We describe the design and fabrication of a ruthenium beam separator used to simultaneously attenuate infrared light and reflect soft x rays. Measurements in the infrared and soft x-ray regions showed the beam separator to have a reflectivity of 50%-85% in the wavelength region from 6 to 10 nm at a grazing incidence angle of 7.5 deg and 4.3% at 800 nm and the same angle of grazing incidence, indicating that the amount of attenuation is 0.05-0.09. These results show that this beam separator could provide an effective means for separating IR light from soft x rays in light generated by high-order harmonic generation sources.

  13. Generation of attosecond x-ray and gamma-ray via Compton backscattering.

    PubMed

    Chung, Sang-Young; Yoon, Moohyun; Kim, Dong Eon

    2009-05-11

    The generation of an isolated attosecond gamma-ray pulse utilizing Compton backscattering of a relativistic electron bunch has been investigated. The energy of the electron bunch is modulated while the electron bunch interacts with a co-propagating few-cycle CEP (carrier envelope phase)-locked laser in a single-period wiggler. The energy-modulated electron bunch interacts with a counter-propagating driver laser, producing Compton back-scattered radiation. The energy modulation of the electron bunch is duplicated to the temporal modulation of the photon energy of Compton back-scattered radiation. The spectral filtering using a crystal spectrometer allows one to obtain an isolated attosecond gamma-ray.

  14. X-ray optics: Diamond brilliance

    NASA Astrophysics Data System (ADS)

    Durbin, Stephen M.; Colella, Roberto

    2010-03-01

    Most materials either absorb or transmit X-rays. This is useful for imaging but makes it notoriously difficult to build mirrors for reflective X-ray optics. A demonstration of the high X-ray reflectivity of diamond could provide a timely solution to make the most of the next generation of free-electron lasers.

  15. Lorentz drift compensation in high harmonic generation in the soft and hard X-ray regions of the spectrum.

    PubMed

    Galloway, Benjamin R; Popmintchev, Dimitar; Pisanty, Emilio; Hickstein, Daniel D; Murnane, Margaret M; Kapteyn, Henry C; Popmintchev, Tenio

    2016-09-19

    We present a semi-classical study of the effects of the Lorentz force on electrons during high harmonic generation in the soft and hard X-ray regions driven by near- and mid-infrared lasers with wavelengths from 0.8 to 20 μm, and at intensities below 1015 W/cm2. The transverse extent of the longitudinal Lorentz drift is compared for both Gaussian focus and waveguide geometries. Both geometries exhibit a longitudinal electric field component that cancels the magnetic Lorentz drift in some regions of the focus, once each full optical cycle. We show that the Lorentz force contributes a super-Gaussian scaling which acts in addition to the dominant high harmonic flux scaling of λ-(5-6) due to quantum diffusion. We predict that the high harmonic yield will be reduced for driving wavelengths > 6 μm, and that the presence of dynamic spatial mode asymmetries results in the generation of both even and odd harmonic orders. Remarkably, we show that under realistic conditions, the recollision process can be controlled and does not shut off completely even for wavelengths >10 μm and recollision energies greater than 15 keV.

  16. Soft x-ray imaging of intracellular granules of filamentous cyanobacterium generating musty smell in Lake Biwa

    NASA Astrophysics Data System (ADS)

    Takemoto, K.; Mizuta, G.; Yamamoto, A.; Yoshimura, M.; Ichise, S.; Namba, H.; Kihara, H.

    2013-10-01

    A planktonic blue-green algae, which are currently identified as Phormidium tenue, was observed by a soft x-ray microscopy (XM) for comparing a musty smell generating green strain (PTG) and a non-smell brown strain (PTB). By XM, cells were clearly imaged, and several intracellular granules which could not be observed under a light microscope were visualized. The diameter of granules was about 0.5-1 μm, and one or a few granules were seen in a cell. XM analyses showed that width of cells and sizes of intracellular granules were quite different between PTG and PTB strains. To study the granules observed by XM, transmission in more detail, transmission electron microscopy (TEM) and indirect fluorescent-antibody technique (IFA) were applied. By TEM, carboxysomes, thylakoids and polyphosphate granules were observed. IFA showed the presence of carboxysomes. Results lead to the conclusion that intracellular granules observed under XM are carboxysomes or polyphosphate granules. These results demonstrate that soft XM is effective for analyzing fine structures of small organisms such as cyanobacterium, and for discriminating the strains which generates musty smells from others.

  17. Proton- and x-ray beams generated by ultra-fast CO(2) lasers for medical applications

    SciTech Connect

    Pogorelsky, I.; Polyanskiy, M.; Yakimenko, V.; Ben-Zvi, I.; Shkolnikov, P. Najmudin, Z.; Palmer, C.A.J.; Dover, N.P.; Oliva, P; Carpinelli, M.

    2011-07-01

    Recent progress in using picosecond CO{sub 2} lasers for Thomson scattering and ion-acceleration experiments underlines their potentials for enabling secondary radiation- and particle-sources. These experiments capitalize on certain advantages of long-wavelength CO{sub 2} lasers, such as higher number of photons per energy unit, and favorable scaling of the electrons ponderomotive energy and critical plasma density. The high-flux x-ray bursts produced by Thomson scattering of the CO{sub 2} laser off a counter-propagating electron beam enabled high-contrast, time-resolved imaging of biological objects in the picosecond time frame. In different experiments, the laser, focused on a hydrogen jet, generated monoenergetic proton beams via the radiation-pressure mechanism. The strong power-scaling of this regime promises realization of proton beams suitable for laser-driven proton cancer therapy after upgrading the CO{sub 2} laser to sub-PW peak power. This planned improvement includes optimizing the 10-{mu}m ultra-short pulse generation, assuring higher amplification in the CO{sub 2} gas under combined isotopic- and power-broadening effects, and shortening the postamplification pulse to a few laser cycles (150-200 fs) via chirping and compression. These developments will move us closer to practical applications of ultra-fast CO{sub 2} lasers in medicine and other areas.

  18. X-Ray Imaging System

    NASA Technical Reports Server (NTRS)

    1986-01-01

    The FluoroScan Imaging System is a high resolution, low radiation device for viewing stationary or moving objects. It resulted from NASA technology developed for x-ray astronomy and Goddard application to a low intensity x-ray imaging scope. FlouroScan Imaging Systems, Inc, (formerly HealthMate, Inc.), a NASA licensee, further refined the FluoroScan System. It is used for examining fractures, placement of catheters, and in veterinary medicine. Its major components include an x-ray generator, scintillator, visible light image intensifier and video display. It is small, light and maneuverable.

  19. Design and characterization of electron beam focusing for X-ray generation in novel medical imaging architecture

    SciTech Connect

    Bogdan Neculaes, V. Zou, Yun; Zavodszky, Peter; Inzinna, Louis; Zhang, Xi; Conway, Kenneth; Caiafa, Antonio; Frutschy, Kristopher; Waters, William; De Man, Bruno

    2014-05-15

    A novel electron beam focusing scheme for medical X-ray sources is described in this paper. Most vacuum based medical X-ray sources today employ a tungsten filament operated in temperature limited regime, with electrostatic focusing tabs for limited range beam optics. This paper presents the electron beam optics designed for the first distributed X-ray source in the world for Computed Tomography (CT) applications. This distributed source includes 32 electron beamlets in a common vacuum chamber, with 32 circular dispenser cathodes operated in space charge limited regime, where the initial circular beam is transformed into an elliptical beam before being collected at the anode. The electron beam optics designed and validated here are at the heart of the first Inverse Geometry CT system, with potential benefits in terms of improved image quality and dramatic X-ray dose reduction for the patient.

  20. Design and characterization of electron beam focusing for X-ray generation in novel medical imaging architecture.

    PubMed

    Bogdan Neculaes, V; Zou, Yun; Zavodszky, Peter; Inzinna, Louis; Zhang, Xi; Conway, Kenneth; Caiafa, Antonio; Frutschy, Kristopher; Waters, William; De Man, Bruno

    2014-05-01

    A novel electron beam focusing scheme for medical X-ray sources is described in this paper. Most vacuum based medical X-ray sources today employ a tungsten filament operated in temperature limited regime, with electrostatic focusing tabs for limited range beam optics. This paper presents the electron beam optics designed for the first distributed X-ray source in the world for Computed Tomography (CT) applications. This distributed source includes 32 electron beamlets in a common vacuum chamber, with 32 circular dispenser cathodes operated in space charge limited regime, where the initial circular beam is transformed into an elliptical beam before being collected at the anode. The electron beam optics designed and validated here are at the heart of the first Inverse Geometry CT system, with potential benefits in terms of improved image quality and dramatic X-ray dose reduction for the patient.

  1. Design and characterization of electron beam focusing for X-ray generation in novel medical imaging architecturea

    PubMed Central

    Bogdan Neculaes, V.; Zou, Yun; Zavodszky, Peter; Inzinna, Louis; Zhang, Xi; Conway, Kenneth; Caiafa, Antonio; Frutschy, Kristopher; Waters, William; De Man, Bruno

    2014-01-01

    A novel electron beam focusing scheme for medical X-ray sources is described in this paper. Most vacuum based medical X-ray sources today employ a tungsten filament operated in temperature limited regime, with electrostatic focusing tabs for limited range beam optics. This paper presents the electron beam optics designed for the first distributed X-ray source in the world for Computed Tomography (CT) applications. This distributed source includes 32 electron beamlets in a common vacuum chamber, with 32 circular dispenser cathodes operated in space charge limited regime, where the initial circular beam is transformed into an elliptical beam before being collected at the anode. The electron beam optics designed and validated here are at the heart of the first Inverse Geometry CT system, with potential benefits in terms of improved image quality and dramatic X-ray dose reduction for the patient. PMID:24826066

  2. The Maria-Goeppert-Mayer Award Lecture: The Science of Ultrashort Pulse Generation, in the Visible and X-Ray Regions of the Spectrum

    NASA Astrophysics Data System (ADS)

    Murnane, Margaret M.

    1997-04-01

    Ultrashort x-ray pulses give researchers a new window through which to view the natural world, with the ability to spatially and temporally resolve processes basic to material and chemical systems. In the 1990's, there has been a revolution in the technology of laser sources, resulting in the ability to simply and reliably produce light pulses as short as 3 optical cycles in duration, both in the visible and the x-ray region of the spectrum. Also, powerful new techniques to obtain accurate pictures of the exact shape of these ultrashort light pulses have been developed, which are revolutionizing the way we think about and use light. Finally, using harmonic techniques to up-convert visible light into the x-ray region, we can generate coherent and tunable light below 5 nm, with unprecedented short duration (3-10 fs).

  3. A High Efficiency Grazing Incidence Pumped X-ray Laser

    SciTech Connect

    Dunn, J; Keenan, R; Price, D F; Patel, P K; Smith, R F; Shlyaptsev, V N

    2006-08-31

    The main objective of the project is to demonstrate a proof-of-principle, new type of high efficiency, short wavelength x-ray laser source that will operate at unprecedented high repetition rates (10Hz) that could be scaled to 1kHz or higher. The development of a high average power, tabletop x-ray laser would serve to complement the wavelength range of 3rd and future 4th generation light sources, e.g. the LCLS, being developed by DOE-Basic Energy Sciences. The latter are large, expensive, central, synchrotron-based facilities while the tabletop x-ray laser is compact, high-power laser-driven, and relatively inexpensive. The demonstration of such a unique, ultra-fast source would allow us to attract funding from DOE-BES, NSF and other agencies to pursue probing of diverse materials undergoing ultrafast changes. Secondly, this capability would have a profound impact on the semiconductor industry since a coherent x-ray laser source would be ideal for ''at wavelength'' {approx}13 nm metrology and microscopy of optics and masks used in EUV lithography. The project has major technical challenges. We will perform grazing-incidence pumped laser-plasma experiments in flat or groove targets which are required to improve the pumping efficiency by ten times. Plasma density characterization using our existing unique picosecond x-ray laser interferometry of laser-irradiated targets is necessary. Simulations of optical laser propagation as well as x-ray laser production and propagation through freely expanding and confined plasma geometries are essential. The research would be conducted using the Physics Directorate Callisto and COMET high power lasers. At the end of the project, we expect to have a high-efficiency x-ray laser scheme operating below 20 nm at 10Hz with a pulse duration of {approx}2 ps. This will represent the state-of-the-art in x-ray lasers and would be a major step forward from our present picosecond laser-driven x-ray lasers. There is an added bonus of creating

  4. Thermal Analysis of Next-Generation Space Telescope (NGST) Mirrors During Optical Testing in the X-Ray Calibration Facility (XRCF)

    NASA Technical Reports Server (NTRS)

    Page, Tim; Sutherlin, Steven

    2002-01-01

    This paper presents Thermal Analysis of the Next Generation Space Telescope (NGST) Mirrors During Optical Testing in the X-Ray Calibration Facility (XRCF). The contents include: 1) NGST Spacecraft Concept; 2) NGST Mirror Development Testing; 3) NGST Development Mirror; 4) Knudsen Number; 5) Free-Molecular Conduction; 6) Accomodation Coefficient; and 7) Results and Recommendations. This paper is presented in viewgraph form.

  5. Peculiarities of detecting pulses of runaway electrons and X-rays generated by high-voltage nanosecond discharges in open atmosphere

    SciTech Connect

    Babich, L. P.; Loiko, T. V.

    2010-03-15

    Peculiarities of detecting pulses of high-energy runaway electrons and the accompanying X-rays generated by high-voltage nanosecond discharges at high overvoltages in dense gases are discussed. Methods for overcoming difficulties encountered in such measurements are demonstrated. Different techniques for detecting runaway electrons and X-rays generated by discharges in open atmosphere are described, and typical errors that may be done when interpreting measurement results are considered. Experiments with the use of a small-size generator of nanosecond pulses with the idle-running voltage of 250-270 kV and stored energy of {approx}0.5 J have been carried out. It is shown that, in measuring runaway electron pulses by using an experimental configuration with a grid anode, a major portion of the recorded signal is attributed to electromagnetic disturbances. It is found that X-rays are mainly generated due to the deceleration of runaway electrons in the anode, rather than in gas. The number of runaway electrons with energies {approx}300 keV does not exceed 10{sup 9} per shot, and the X-ray dose is 60-200 {mu}R/shot, depending on the anode material.

  6. Atmospheric electron x-ray spectrometer

    NASA Technical Reports Server (NTRS)

    Feldman, Jason E. (Inventor); George, Thomas (Inventor); Wilcox, Jaroslava Z. (Inventor)

    2002-01-01

    The present invention comprises an apparatus for performing in-situ elemental analyses of surfaces. The invention comprises an atmospheric electron x-ray spectrometer with an electron column which generates, accelerates, and focuses electrons in a column which is isolated from ambient pressure by a:thin, electron transparent membrane. After passing through the membrane, the electrons impinge on the sample in atmosphere to generate characteristic x-rays. An x-ray detector, shaping amplifier, and multi-channel analyzer are used for x-ray detection and signal analysis. By comparing the resultant data to known x-ray spectral signatures, the elemental composition of the surface can be determined.

  7. 4th Annual SATN Conference 2011: Curriculum Transformation at Universities of Technology: Towards Development of New Generation Universities

    ERIC Educational Resources Information Center

    Mthembu, T.

    2012-01-01

    The South African Technology Network (SATN) would like to thank the Editor of the "South African Journal of Higher Education" (SAJHE) for the opportunity to publish papers read at the 4th Annual SATN Conference that was hosted by Central University of Technology and held in Bloemfontein in November 2011. The journal makes it possible for…

  8. X-ray diagnostics of imploding plasmas from planar wire arrays composed of Cu and few tracer Al wires on the 1MA pulsed power generator at UNR.

    PubMed

    Safronova, A S; Kantsyrev, V L; Esaulov, A A; Ouart, N D; Yilmaz, M F; Williamson, K M; Shlyaptseva, V; Shrestha, I; Osborne, G C; Coverdale, C A; Jones, B; Deeney, C

    2008-10-01

    Tracer aluminum alloyed wires (Al5056) are used to provide additional information for x-ray diagnostics of implosions of Cu planar wire arrays (PWAs). Specifically, the analysis of combined PWA experiments using the extensive set of x-ray diagnostics is presented. In these experiments, which were conducted at the 1MA pulsed power generator at University of Nevada, Reno, the Z-pinch load consisted of several (eight) Cu alloyed (main material) and one to two Al alloyed (tracer) wires mounted in a single plane row or double parallel plane rows, single planar wire array (SPWA) or double planar wire array (DPWA), respectively. The analysis of x-ray spatially resolved spectra from the main material indicates the increase in the electron temperature T(e) near the cathode. In general, the axial gradients in T(e) are more pronounced for SPWA than for DPWA due to the more "columnlike" plasma formation for SPWA compared to "hot-spot-like" plasma formation for DPWA. In addition, x-ray spectra from tracer wires are studied, and estimated plasma parameters are compared with those from the main material. It is observed that the x-ray K-shell Al spectra manifest more opacity features for the case of SPWA with about 18% of Al mass (to the total load mass) compared to the case of DPWA with about 11% of Al mass. The analysis of time-gated spectra shows that the relative intensity of the most intense K-shell Al line, small before the x-ray burst, increases with time and peaks close to the maximum of the sub-keV signal.

  9. X-ray (image)

    MedlinePlus

    X-rays are a form of ionizing radiation that can penetrate the body to form an image on ... will be shades of gray depending on density. X-rays can provide information about obstructions, tumors, and other ...

  10. Bone x-ray

    MedlinePlus

    ... not being scanned. Alternative Names X-ray - bone Images Skeleton Skeletal spine Osteogenic sarcoma - x-ray References ... urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows ...

  11. X-ray

    MedlinePlus

    ... think you might be pregnant. Alternative Names Radiography Images X-ray X-ray References Geleijns J, Tack ... urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows ...

  12. Extremity x-ray

    MedlinePlus

    ... sensitive to the risks of an x-ray. Images X-ray References Kelly DM. Congenital anomalies of ... urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows ...

  13. X-Ray Toolkit

    SciTech Connect

    2015-10-20

    Radiographic Image Acquisition & Processing Software for Security Markets. Used in operation of commercial x-ray scanners and manipulation of x-ray images for emergency responders including State, Local, Federal, and US Military bomb technicians and analysts.

  14. 20-100 keV K(alpha) X-Ray Source Generation by Short Pulse High Intensity Lasers

    SciTech Connect

    Park, H-S; Koch, J A; Landen, O L; Phillips, T W; Goldsack, T

    2003-08-22

    We are studying the feasibility of utilizing K{alpha} x-ray sources in the range of 20 to 100 keV as a backlighters for imaging various stages of implosions and high areal density planar samples driven by the NIF laser facility. The hard x-ray K{alpha} sources are created by relativistic electron plasma interactions in the target material after a radiation by short pulse high intensity lasers. In order to understand K{alpha} source characteristics such as production efficiency and brightness as a function of laser parameters, we have performed experiments using the 10 J, 100 fs JanUSP laser. We utilized single-photon counting spectroscopy and x-ray imaging diagnostics to characterize the K{alpha} source. We find that the K{alpha} conversion efficiency from the laser energy is {approx} 3 x 10{sup -4}.

  15. Simulation of the generation of the characteristic X-ray emission by hot electrons in a foil

    SciTech Connect

    Kostenko, O F; Andreev, N E

    2013-03-31

    We have developed a model to calculate the yield of the characteristic X-ray radiation from a foil, taking into account the dependence of the average energy and the number of hot electrons on the intensity of the laser pulse, the self-absorption of X-rays and the effect of refluxing of hot electrons. The yield of K{sub {alpha}} radiation from a silver foil is optimised at relativistic intensities. A method is proposed for diagnosing the effect of electron refluxing, which greatly increases the yield of K{sub {alpha}} radiation. (extreme light fields and their applications)

  16. Sinus x-ray

    MedlinePlus

    Paranasal sinus radiography; X-ray - sinuses ... sinus x-ray is taken in a hospital radiology department. Or the x-ray may be taken ... Brown J, Rout J. ENT, neck, and dental radiology. In: Adam A, Dixon AK, Gillard JH Schaefer- ...

  17. Hand x-ray

    MedlinePlus

    X-ray - hand ... A hand x-ray is taken in a hospital radiology department or your health care provider's office by an ... technician. You will be asked to place your hand on the x-ray table, and keep it ...

  18. Multi-mJ mid-infrared kHz OPCPA and Yb-doped pump lasers for tabletop coherent soft x-ray generation

    NASA Astrophysics Data System (ADS)

    Lai, Chien-Jen; Hong, Kyung-Han; Siqueira, Jonathas P.; Krogen, Peter; Chang, Chun-Lin; Stein, Gregory J.; Liang, Houkun; Keathley, Phillip D.; Laurent, Guillaume; Moses, Jeffrey; Zapata, Luis E.; Kärtner, Franz X.

    2015-09-01

    We present our recent progress on the development of a mid-infrared (mid-IR), multi-mJ, kHz optical parametric chirped-pulse amplification (OPCPA) system, pumped by a homebuilt picosecond cryogenic Yb:YAG chirped-pulse amplifier, and its application to soft x-ray high-order harmonic generation. The cryogenic Yb:YAG laser operating at 1 kHz repetition rate delivers 42 mJ, 17 ps, 1.03 μm pulses to pump the OPCPA system. Efficient second and fourth harmonic generations from the Yb:YAG system are demonstrated, which provide the pumping capability for OPCPA at various wavelengths. The mid-IR OPCPA system produces 2.6 mJ, 39 fs, 2.1 μm pulses with good beam quality (M 2 = ∼1.5) at 1 kHz repetition rate. The output pulses of the OPCPA are used to generate high-order harmonics in both gas cell and hollow-core fiber targets. A photon flux of ∼2 × 108 photon/s/1% bandwidth at 160 eV in Ar is measured while the cutoff is 190 eV. The direct measurements of the photon flux from x-ray photodiodes have confirmed the generation of water-window soft x-ray photons with a flux ∼106 photon/s/1% bandwidth at 330 eV in Ne. The demonstrated OPCPA and Yb:YAG pump laser technologies provide an excellent platform of energy and power scalable few-cycle mid-IR sources that are suitable for high-flux tabletop coherent soft x-ray generation.

  19. Diffraction leveraged modulation of X-ray pulses using MEMS-based X-ray optics

    DOEpatents

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

    2016-08-09

    A method and apparatus are provided for implementing Bragg-diffraction leveraged modulation of X-ray pulses using MicroElectroMechanical systems (MEMS) based diffractive optics. An oscillating crystalline MEMS device generates a controllable time-window for diffraction of the incident X-ray radiation. The Bragg-diffraction leveraged modulation of X-ray pulses includes isolating a particular pulse, spatially separating individual pulses, and spreading a single pulse from an X-ray pulse-train.

  20. Optimal generation of spatially coherent soft X-ray isolated attosecond pulses in a gas-filled waveguide using two-color synthesized laser pulses

    PubMed Central

    Jin, Cheng; Hong, Kyung-Han; Lin, C. D.

    2016-01-01

    We numerically demonstrate the generation of intense, low-divergence soft X-ray isolated attosecond pulses in a gas-filled hollow waveguide using synthesized few-cycle two-color laser waveforms. The waveform is a superposition of a fundamental and its second harmonic optimized such that highest harmonic yields are emitted from each atom. We then optimize the gas pressure and the length and radius of the waveguide such that bright coherent high-order harmonics with angular divergence smaller than 1 mrad are generated, for photon energy from the extreme ultraviolet to soft X-rays. By selecting a proper spectral range enhanced isolated attosecond pulses are generated. We study how dynamic phase matching caused by the interplay among waveguide mode, neutral atomic dispersion, and plasma effect is achieved at the optimal macroscopic conditions, by performing time-frequency analysis and by analyzing the evolution of the driving laser’s electric field during the propagation. Our results, when combined with the on-going push of high-repetition-rate lasers (sub- to few MHz’s) may eventually lead to the generation of high-flux, low-divergence soft X-ray tabletop isolated attosecond pulses for applications. PMID:27929036

  1. Generation of Bright, Spatially Coherent Soft X-Ray High Harmonics in a Hollow Waveguide Using Two-Color Synthesized Laser Pulses

    NASA Astrophysics Data System (ADS)

    Jin, Cheng; Stein, Gregory J.; Hong, Kyung-Han; Lin, C. D.

    2015-07-01

    We investigate the efficient generation of low-divergence high-order harmonics driven by waveform-optimized laser pulses in a gas-filled hollow waveguide. The drive waveform is obtained by synthesizing two-color laser pulses, optimized such that highest harmonic yields are emitted from each atom. Optimization of the gas pressure and waveguide configuration has enabled us to produce bright and spatially coherent harmonics extending from the extreme ultraviolet to soft x rays. Our study on the interplay among waveguide mode, atomic dispersion, and plasma effect uncovers how dynamic phase matching is accomplished and how an optimized waveform is maintained when optimal waveguide parameters (radius and length) and gas pressure are identified. Our analysis should help laboratory development in the generation of high-flux bright coherent soft x rays as tabletop light sources for applications.

  2. X-ray generation by fast electrons propagating in nanofibres irradiated by a laser pulse of relativistic intensity

    SciTech Connect

    Andreev, A A; Platonov, K Yu

    2016-02-28

    Numerical simulations were made of the interaction of a relativistically intense laser pulse with a target consisting of nanometre fibres. Fast electrons were shown to execute forced betatron oscillations in the electrostatic fibre field and the laser field. The fibre diameter was determined whereby the amplitude of betatron electron oscillations is resonantly increased. The power of coherent X-ray betatron radiation of the electron bunch was calculated outside of the resonance domain and in the resonance case. We showed that the laser-to-X-ray betatron radiation conversion coefficient in the resonance case amounts to a few percent and the target made up of nanometre fibres may be regarded as an efficient laser-driven source of coherent X- and gamma-ray radiation. (interaction of laser radiation with matter. laser plasma)

  3. Method of Generating X-Ray Diffraction Data for Integral Detection of Twin Defects in Super-Hetero-Epitaxial Materials

    NASA Technical Reports Server (NTRS)

    Park, Yeonjoon (Inventor); Choi, Sang Hyouk (Inventor); King, Glen C. (Inventor); Elliott, James R. (Inventor)

    2009-01-01

    A method provides X-ray diffraction (XRD) data suitable for integral detection of a twin defect in a strained or lattice-matched epitaxial material made from components having crystal structures having symme try belonging to different space groups. The material is mounted in a n X-ray diffraction (XRD) system. In one embodiment, the XRD system's goniometer angle Omega is set equal to (Theta(sub B)-Beta) where The ta(sub B) is a Bragg angle for a designated crystal plane of the allo y that is disposed at a non-perpendicular orientation with respect to the {111) crystal plane, and Beta is the angle between the designate d crystal plane and a { 111 } crystal plane of one of the epitaxial components. The XRD system's detector angle is set equal to (Theta(su b B)+Beta). The material can be rotated through an angle of azimuthal rotation Phi about the axis aligned with the material. Using the det ector, the intensity of the X-ray diffraction is recorded at least at the angle at which the twin defect occurs.

  4. Development of Multilayer Analyzer Array Detectors for X-ray Fluorescence at the Third Generation Synchrotron Source

    NASA Astrophysics Data System (ADS)

    Zhang, K.; Rosenbaum, G.; Liu, R.; Liu, C.; Carmeli, C.; Bunker, G.; Fischer, D.

    2004-05-01

    The development of Multilayer Analyzer Array Detector (MAAD) for X-ray fluorescence eliminates the count rate limitation encountered with multi-element Ge detectors. A 24-element multilayer detector has been fabricated that is tunable in a large energy region. This detector has been operational for more than two years at the BioCAT Beamline of the Advanced Photon Source at Argonne National Laboratory. Here we report our recent progress in developing multilayer detectors working in lower energy regions, in particular, performance at Ca Kα fluorescence energy and test results at soft x-ray energies. The band width of the analyzer response is found to be 3-4% of the fluorescence energy. Namely, at the Ca Kα energy, the band width is 140 eV; it is reduced to about 60 eV at Al Kα fluorescence energy. The throughput of the detector in this energy region (1.5-3.6 KeV) is 20% to 30%. These results demonstrate the feasibility for constructing multilayer analyzer array detectors for use in the soft x-ray region.

  5. Reflection soft X-ray microscope and method

    DOEpatents

    Suckewer, S.; Skinner, C.H.; Rosser, R.

    1993-01-05

    A reflection soft X-ray microscope is provided by generating soft X-ray beams, condensing the X-ray beams to strike a surface of an object at a predetermined angle, and focusing the X-ray beams reflected from the surface onto a detector, for recording an image of the surface or near surface features of the object under observation.

  6. Reflection soft X-ray microscope and method

    DOEpatents

    Suckewer, Szymon; Skinner, Charles H.; Rosser, Roy

    1993-01-01

    A reflection soft X-ray microscope is provided by generating soft X-ray beams, condensing the X-ray beams to strike a surface of an object at a predetermined angle, and focusing the X-ray beams reflected from the surface onto a detector, for recording an image of the surface or near surface features of the object under observation.

  7. X-ray binaries

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Satellite X-ray experiments and ground-based programs aimed at observation of X-ray binaries are discussed. Experiments aboard OAO-3, OSO-8, Ariel 5, Uhuru, and Skylab are included along with rocket and ground-based observations. Major topics covered are: Her X-1, Cyg X-3, Cen X-3, Cyg X-1, the transient source A0620-00, other possible X-ray binaries, and plans and prospects for future observational programs.

  8. Using hard-X-ray images of ignition hohlraums on NIF to characterize hot electrons generated by laser-plasma interaction

    NASA Astrophysics Data System (ADS)

    Divol, Laurent; Doeppner, T.; Thomas, C.; Dewald, E.; Park, H.; Schneider, M.; Lacaille, G.; Michel, P.; Town, R.; Meezan, N.; Moody, J.; Kline, J.; Glenzer, S.; Landen, O.

    2011-10-01

    Using multi-channel hard X-ray images of an ignition hohlraum taken along two axis and the time-integrated FFLEX broadband spectrometer that measures Bremsstrahlung hard X-rays emitted in the hohlraum wall by energetic electrons, we characterize the location of hot electron generation. We distinguish two hot electron components of the spectrum: a 20 keV thermal-like component related to Stimulated Raman scattering and a ``super ho'' (>60 keV) component due to LPI at higher density. In addition, the effect of the hohlraum thermal emission (with Thot ~ 2-4 keV) on this analysis will be assessed. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  9. Dependence of optimal initial density on laser parameters for multi-keV x-ray radiators generated by nanosecond laser-produced underdense plasma

    SciTech Connect

    Tu, Shao-yong; Yuan, Yong-teng; Miao, Wen-yong; Jiang, Shao-en; Ding, Yong-kun; Hu, Guang-yue Zhao, Bin; Zheng, Jian

    2016-01-15

    Efficient multi-keV x-ray sources can be produced using nanosecond laser pulse-heated middle-Z underdense plasmas generated using gas or foam. Previous experimental results show that an optimal initial target density exists for efficient multi-keV x-ray emission at which the laser ionization wave is supersonic. Here we explore the influence of the laser intensity and the pulse duration on this optimal initial target density via a one-dimensional radiation hydrodynamic simulation. The simulation shows that the optimal initial density is sensitive to both the laser intensity and the pulse duration. However, the speed of the supersonic ionization wave at the end of the laser irradiation is always maintained at 1.5 to 1.7 times that of the ion acoustic wave under the optimal initial density conditions.

  10. X-rays surgical revolution.

    PubMed

    Toledo-Pereyra, Luis H

    2009-01-01

    Wilhelm Roentgen (1845-1923) created a surgical revolution with the discovery of the X-rays in late 1895 and the subsequent introduction of this technique for the management of surgical patients. No other physician or scientist had ever imagined such a powerful and worthwhile discovery. Other scientists paved the way for Roentgen to approach the use of these new X-rays for medical purposes. In this way, initially, and prior to Roentgen, Thompson, Hertz, and Lenard applied themselves to the early developments of this technology. They made good advances but never reached the clearly defined understanding brought about by Roentgen. The use of a Crookes tube, a barium platinocyanide screen, with fluorescent light and the generation of energy to propagate the cathode rays were the necessary elements for the conception of an X-ray picture. On November 8, 1895, Roentgen began his experiments on X-ray technology when he found that some kind of rays were being produced by the glass of the tube opposite to the cathode. The development of a photograph successfully completed this early imaging process. After six intense weeks of research, on December 22, he obtained a photograph of the hand of his wife, the first X-ray ever made. This would be a major contribution to the world of medicine and surgery.

  11. X-ray transmissive debris shield

    DOEpatents

    Spielman, Rick B.

    1994-01-01

    A composite window structure is described for transmitting x-ray radiation and for shielding radiation generated debris. In particular, separate layers of different x-ray transmissive materials are laminated together to form a high strength, x-ray transmissive debris shield which is particularly suited for use in high energy fluences. In one embodiment, the composite window comprises alternating layers of beryllium and a thermoset polymer.

  12. Topological X-Rays and MRIs

    ERIC Educational Resources Information Center

    Lynch, Mark

    2002-01-01

    Let K be a compact subset of the interior of the unit disk D in the plane and suppose one can't see through the boundary of D and identify K. However, assume that one can take "topological X-rays" of D which measure the "density" of K along the lines of the X-rays. By taking these X-rays from all directions, a "topological MRI" is generated for…

  13. Controlling X-rays With Light

    SciTech Connect

    Glover, Ernie; Hertlein, Marcus; Southworth, Steve; Allison, Tom; van Tilborg, Jeroen; Kanter, Elliot; Krassig, B.; Varma, H.; Rude, Bruce; Santra, Robin; Belkacem, Ali; Young, Linda

    2010-08-02

    Ultrafast x-ray science is an exciting frontier that promises the visualization of electronic, atomic and molecular dynamics on atomic time and length scales. A largelyunexplored area of ultrafast x-ray science is the use of light to control how x-rays interact with matter. In order to extend control concepts established for long wavelengthprobes to the x-ray regime, the optical control field must drive a coherent electronic response on a timescale comparable to femtosecond core-hole lifetimes. An intense field is required to achieve this rapid response. Here an intense optical control pulse isobserved to efficiently modulate photoelectric absorption for x-rays and to create an ultrafast transparency window. We demonstrate an application of x-ray transparencyrelevant to ultrafast x-ray sources: an all-photonic temporal cross-correlation measurement of a femtosecond x-ray pulse. The ability to control x-ray/matterinteractions with light will create new opportunities at current and next-generation x-ray light sources.

  14. Controlling x-rays with light.

    SciTech Connect

    Glover, T. E.; Hertlein, M. P.; Southworth, S. H.; Allison, T. K.; van Tilborg, J.; Kanter, E. P.; Krassig, B.; Varma, H. R.; Rude, B.; Santra, R.; Belkacem, A.; Young, L.; Chemical Sciences and Engineering Division; LBNL; Univ. of California at Berkley; Univ. of Chicago

    2010-01-01

    Ultrafast X-ray science is an exciting frontier that promises the visualization of electronic, atomic and molecular dynamics on atomic time and length scales. A largely unexplored area of ultrafast X-ray science is the use of light to control how X-rays interact with matter. To extend control concepts established for long-wavelength probes to the X-ray regime, the optical control field must drive a coherent electronic response on a timescale comparable to femtosecond core-hole lifetimes. An intense field is required to achieve this rapid response. Here, an intense optical control pulse is observed to efficiently modulate photoelectric absorption for X-rays and to create an ultrafast transparency window. We demonstrate an application of X-ray transparency relevant to ultrafast X-ray sources: an all-photonic temporal cross-correlation measurement of a femtosecond X-ray pulse. The ability to control X-ray-matter interactions with light will create new opportunities for present and next-generation X-ray light sources.

  15. Controlling X-rays with light

    NASA Astrophysics Data System (ADS)

    Glover, T. E.; Hertlein, M. P.; Southworth, S. H.; Allison, T. K.; van Tilborg, J.; Kanter, E. P.; Krässig, B.; Varma, H. R.; Rude, B.; Santra, R.; Belkacem, A.; Young, L.

    2010-01-01

    Ultrafast X-ray science is an exciting frontier that promises the visualization of electronic, atomic and molecular dynamics on atomic time and length scales. A largely unexplored area of ultrafast X-ray science is the use of light to control how X-rays interact with matter. To extend control concepts established for long-wavelength probes to the X-ray regime, the optical control field must drive a coherent electronic response on a timescale comparable to femtosecond core-hole lifetimes. An intense field is required to achieve this rapid response. Here, an intense optical control pulse is observed to efficiently modulate photoelectric absorption for X-rays and to create an ultrafast transparency window. We demonstrate an application of X-ray transparency relevant to ultrafast X-ray sources: an all-photonic temporal cross-correlation measurement of a femtosecond X-ray pulse. The ability to control X-ray-matter interactions with light will create new opportunities for present and next-generation X-ray light sources.

  16. A Next-Generation Hard X-Ray Nanoprobe Beamline for In Situ Studies of Energy Materials and Devices

    NASA Astrophysics Data System (ADS)

    Maser, Jörg; Lai, Barry; Buonassisi, Tonio; Cai, Zhonghou; Chen, Si; Finney, Lydia; Gleber, Sophie-Charlotte; Jacobsen, Chris; Preissner, Curt; Roehrig, Chris; Rose, Volker; Shu, Deming; Vine, David; Vogt, Stefan

    2014-01-01

    The Advanced Photon Source is developing a suite of new X-ray beamlines to study materials and devices across many length scales and under real conditions. One of the flagship beamlines of the APS upgrade is the In Situ Nanoprobe (ISN) beamline, which will provide in situ and operando characterization of advanced energy materials and devices under varying temperatures, gas ambients, and applied fields, at previously unavailable spatial resolution and throughput. Examples of materials systems include inorganic and organic photovoltaic systems, advanced battery systems, fuel cell components, nanoelectronic devices, advanced building materials and other scientifically and technologically relevant systems. To characterize these systems at very high spatial resolution and trace sensitivity, the ISN will use both nanofocusing mirrors and diffractive optics to achieve spots sizes as small as 20 nm. Nanofocusing mirrors in Kirkpatrick-Baez geometry will provide several orders of magnitude increase in photon flux at a spatial resolution of 50 nm. Diffractive optics such as zone plates and/or multilayer Laue lenses will provide a highest spatial resolution of 20 nm. Coherent diffraction methods will be used to study even small specimen features with sub-10 nm relevant length scale. A high-throughput data acquisition system will be employed to significantly increase operations efficiency and usability of the instrument. The ISN will provide full spectroscopy capabilities to study the chemical state of most materials in the periodic table, and enable X-ray fluorescence tomography. In situ electrical characterization will enable operando studies of energy and electronic devices such as photovoltaic systems and batteries. We describe the optical concept for the ISN beamline, the technical design, and the approach for enabling a broad variety of in situ studies. We furthermore discuss the application of hard X-ray microscopy to study defects in multi-crystalline solar cells, one

  17. A Next-Generation Hard X-Ray Nanoprobe Beamline for In Situ Studies of Energy Materials and Devices

    SciTech Connect

    Maser, Jong; Lai, Barry; Buonassisi, Toni; Cai, Zhonghou; Chen, Si; Finney, Lydia; Gleber, Sophie-Charlotte; Jacobsen, Chris; Preissner, Curt; Chris Roehrig; Rose, Volker; Shu, Deming; Vine, David; Vogt, Stefan

    2013-08-20

    The Advanced Photon Source is developing a suite of new X-ray beamlines to study materials and devices across many length scales and under real conditions. One of the flagship beamlines of the APS upgrade is the In Situ Nanoprobe (ISN) beamline, which will provide in situ and operando characterization of advanced energy materials and devices under varying temperatures, gas ambients, and applied fields, at previously unavailable spatial resolution and throughput. Examples of materials systems include inorganic and organic photovoltaic systems, advanced battery systems, fuel cell components, nanoelectronic devices, advanced building materials and other scientifically and technologically relevant systems. To characterize these systems at very high spatial resolution and trace sensitivity, the ISN will use both nanofocusing mirrors and diffractive optics to achieve spots sizes as small as 20 nm. Nanofocusing mirrors in Kirkpatrick–Baez geometry will provide several orders of magnitude increase in photon flux at a spatial resolution of 50 nm. Diffractive optics such as zone plates and/or multilayer Laue lenses will provide a highest spatial resolution of 20 nm. Coherent diffraction methods will be used to study even small specimen features with sub-10 nm relevant length scale. A high-throughput data acquisition system will be employed to significantly increase operations efficiency and usability of the instrument. The ISN will provide full spectroscopy capabilities to study the chemical state of most materials in the periodic table, and enable X-ray fluorescence tomography. In situ electrical characterization will enable operando studies of energy and electronic devices such as photovoltaic systems and batteries. We also describe the optical concept for the ISN beamline, the technical design, and the approach for enabling a broad variety of in situ studies. Furthermore, we discuss the application of hard X-ray microscopy to study defects in multi-crystalline solar

  18. HYBRID simulations of diffraction-limited focusing with Kirkpatrick-Baez mirrors for a next-generation In Situ hard X-ray nanoprobe

    DOE PAGES

    Maser, Jorg; Shi, Xianbo; Reininger, Ruben; ...

    2016-02-22

    Next-generation hard X-ray nanoprobe beamlines such as the In Situ Nanoprobe (ISN) beamline being planned at the Advanced Photon Source aim at providing very high spatial resolution while also enabling very high focused flux, to study complex materials and devices using fast, multidimensional imaging across many length scales. The ISN will use diffractive optics to focus X-rays with a bandpass of ΔE/E = 10–4 into a focal spot of 20 nm or below. Reflective optics in Kirkpatrick-Baez geometry will be used to focus X-rays with a bandpass as large as ΔE/E = 10–2 into a focal spot of 50 nm.more » Diffraction-limited focusing with reflective optics is achieved by spatial filtering and use of a very long, vertically focusing mirror. Furthermore, to quantify the performance of the ISN beamline, we have simulated the propagation of both partially and fully coherent wavefronts from the undulator source, through the ISN beamline and into the mirror-based focal spot. Simulations were carried out using the recently developed software “HYBRID.”« less

  19. Origin of a Raman scattering peak generated in single-walled carbon nanotubes by X-ray irradiation and subsequent thermal annealing

    NASA Astrophysics Data System (ADS)

    Murakami, Toshiya; Matsuda, Mitsuaki; Kisoda, Kenji; Itoh, Chihiro

    2016-08-01

    We have found that a Raman scattering (RS) peak around 1870 cm-1 was produced by the annealing of the X-ray irradiated film of single-walled carbon nanotubes (SWNTs) at 450 oC. The intensity of 1870-cm-1 peak showed a maximum at the probe energy of 2.3 eV for the RS spectroscopy with various probe lasers. Both the peak position and the probe-energy dependence were almost identical to those of the one-dimensional carbon chains previously reported in multi-walled carbon nanotubes. Consequently, we concluded that the 1870-cm-1 peak found in the present study is attributed to carbon chains. The formation of carbon chains by the annealing at temperature lower than 500 oC is firstly reported by the present study. The carbon chains would be formed by aggregation of the interstitial carbons, which are formed as a counterpart of carbon vacancies by X-ray irradiation diffused on SWNT walls. The result indicates that the combination of X-ray irradiation and subsequent thermal annealing is a feasible tool for generating new nanostructures in SWNT.

  20. HYBRID simulations of diffraction-limited focusing with Kirkpatrick-Baez mirrors for a next-generation In Situ hard X-ray nanoprobe

    SciTech Connect

    Maser, Jorg; Shi, Xianbo; Reininger, Ruben; Lai, Barry; Vogt, Stefan

    2016-02-22

    Next-generation hard X-ray nanoprobe beamlines such as the In Situ Nanoprobe (ISN) beamline being planned at the Advanced Photon Source aim at providing very high spatial resolution while also enabling very high focused flux, to study complex materials and devices using fast, multidimensional imaging across many length scales. The ISN will use diffractive optics to focus X-rays with a bandpass of ΔE/E = 10–4 into a focal spot of 20 nm or below. Reflective optics in Kirkpatrick-Baez geometry will be used to focus X-rays with a bandpass as large as ΔE/E = 10–2 into a focal spot of 50 nm. Diffraction-limited focusing with reflective optics is achieved by spatial filtering and use of a very long, vertically focusing mirror. Furthermore, to quantify the performance of the ISN beamline, we have simulated the propagation of both partially and fully coherent wavefronts from the undulator source, through the ISN beamline and into the mirror-based focal spot. Simulations were carried out using the recently developed software “HYBRID.”

  1. HYBRID Simulations of Diffraction-Limited Focusing with Kirkpatrick-Baez Mirrors for a Next-Generation In Situ Hard X-ray Nanoprobe

    NASA Astrophysics Data System (ADS)

    Maser, Jörg; Shi, Xianbo; Reininger, Ruben; Lai, Barry; Vogt, Stefan

    2016-12-01

    Next-generation hard X-ray nanoprobe beamlines such as the In Situ Nanoprobe (ISN) beamline being planned at the Advanced Photon Source aim at providing very high spatial resolution while also enabling very high focused flux, to study complex materials and devices using fast, multidimensional imaging across many length scales. The ISN will use diffractive optics to focus X-rays with a bandpass of ∆ E/ E = 10-4 into a focal spot of 20 nm or below. Reflective optics in Kirkpatrick-Baez geometry will be used to focus X-rays with a bandpass as large as ∆ E/ E = 10-2 into a focal spot of 50 nm. Diffraction-limited focusing with reflective optics is achieved by spatial filtering and use of a very long, vertically focusing mirror. To quantify the performance of the ISN beamline, we have simulated the propagation of both partially and fully coherent wavefronts from the undulator source, through the ISN beamline and into the mirror-based focal spot. Simulations were carried out using the recently developed software " HYBRID."

  2. X-Ray

    MedlinePlus

    ... of gray. For some types of X-ray tests, a contrast medium — such as iodine or barium — is introduced into your body to provide greater detail on the images. X-ray technology is used to examine many parts of the ...

  3. Chest X-Ray

    MedlinePlus Videos and Cool Tools

    ... Site Index A-Z Spotlight Recently posted: Anal Cancer Facet Joint Block Video: Lung Cancer Screening Video: Upper GI Tract X-ray Video: ... of lung conditions such as pneumonia, emphysema and cancer. A chest x-ray requires no special preparation. ...

  4. X-ray Spectrometry.

    ERIC Educational Resources Information Center

    Markowicz, Andrzej A.; Van Grieken, Rene E.

    1984-01-01

    Provided is a selective literature survey of X-ray spectrometry from late 1981 to late 1983. Literature examined focuses on: excitation (photon and electron excitation and particle-induced X-ray emission; detection (wavelength-dispersive and energy-dispersive spectrometry); instrumentation and techniques; and on such quantitative analytical…

  5. X-ray beamsplitter

    DOEpatents

    Ceglio, Natale M.; Stearns, Daniel S.; Hawryluk, Andrew M.; Barbee, Jr., Troy W.

    1989-01-01

    An x-ray beamsplitter which splits an x-ray beam into two coherent parts by reflecting and transmitting some fraction of an incident beam has applications for x-ray interferometry, x-ray holography, x-ray beam manipulation, and x-ray laser cavity output couplers. The beamsplitter is formed of a wavelength selective multilayer thin film supported by a very thin x-ray transparent membrane. The beamsplitter resonantly transmits and reflects x-rays through thin film interference effects. A thin film is formed of 5-50 pairs of alternate Mo/Si layers with a period of 20-250 A. The support membrane is 10-200 nm of silicon nitride or boron nitride. The multilayer/support membrane structure is formed across a window in a substrate by first forming the structure on a solid substrate and then forming a window in the substrate to leave a free-standing structure over the window.

  6. Dental x-rays

    MedlinePlus

    ... X-rays are a form of high energy electromagnetic radiation. The x-rays penetrate the body to form ... for detecting cavities, unless the decay is very advanced and deep. Many ... The amount of radiation given off during the procedure is less than ...

  7. X-ray beamsplitter

    DOEpatents

    Ceglio, N.M.; Stearns, D.G.; Hawryluk, A.M.; Barbee, T.W. Jr.

    1987-08-07

    An x-ray beamsplitter which splits an x-ray beam into two coherent parts by reflecting and transmitting some fraction of an incident beam has applications for x-ray interferometry, x-ray holography, x-ray beam manipulation, and x-ray laser cavity output couplers. The beamsplitter is formed of a wavelength selective multilayer thin film supported by a very thin x-ray transparent membrane. The beamsplitter resonantly transmits and reflects x-rays through thin film interference effects. A thin film is formed of 5--50 pairs of alternate Mo/Si layers with a period of 20--250 A. The support membrane is 10--200 nm of silicon nitride or boron nitride. The multilayer/support membrane structure is formed across a window in a substrate by first forming the structure on a solid substrate and then forming a window in the substrate to leave a free-standing structure over the window. 6 figs.

  8. Bent crystal X-ray topography

    NASA Technical Reports Server (NTRS)

    Parker, D. L.

    1978-01-01

    A television X-ray topographic camera system was constructed. The system differs from the previous system in that it incorporates the X-ray TV imaging system and has a semi-automatic wafer loading system. Also the X-ray diffraction is in a vertical plane. This feature makes wafer loading easier and makes the system compatible with any commercial X-ray generating system. Topographs and results obtained from a study of the diffraction contrast variation with impurity concentration for both boron implanted and boron diffused silicon are included.

  9. In vivo crystallography at X-ray free-electron lasers: the next generation of structural biology?

    PubMed

    Gallat, François-Xavier; Matsugaki, Naohiro; Coussens, Nathan P; Yagi, Koichiro J; Boudes, Marion; Higashi, Tetsuya; Tsuji, Daisuke; Tatano, Yutaka; Suzuki, Mamoru; Mizohata, Eiichi; Tono, Kensuke; Joti, Yasumasa; Kameshima, Takashi; Park, Jaehyun; Song, Changyong; Hatsui, Takaki; Yabashi, Makina; Nango, Eriko; Itoh, Kohji; Coulibaly, Fasséli; Tobe, Stephen; Ramaswamy, S; Stay, Barbara; Iwata, So; Chavas, Leonard M G

    2014-07-17

    The serendipitous discovery of the spontaneous growth of protein crystals inside cells has opened the field of crystallography to chemically unmodified samples directly available from their natural environment. On the one hand, through in vivo crystallography, protocols for protein crystal preparation can be highly simplified, although the technique suffers from difficulties in sampling, particularly in the extraction of the crystals from the cells partly due to their small sizes. On the other hand, the extremely intense X-ray pulses emerging from X-ray free-electron laser (XFEL) sources, along with the appearance of serial femtosecond crystallography (SFX) is a milestone for radiation damage-free protein structural studies but requires micrometre-size crystals. The combination of SFX with in vivo crystallography has the potential to boost the applicability of these techniques, eventually bringing the field to the point where in vitro sample manipulations will no longer be required, and direct imaging of the crystals from within the cells will be achievable. To fully appreciate the diverse aspects of sample characterization, handling and analysis, SFX experiments at the Japanese SPring-8 angstrom compact free-electron laser were scheduled on various types of in vivo grown crystals. The first experiments have demonstrated the feasibility of the approach and suggest that future in vivo crystallography applications at XFELs will be another alternative to nano-crystallography.

  10. Ultrashort X-ray pulse science

    SciTech Connect

    Chin, Alan Hap

    1998-05-01

    A variety of phenomena involves atomic motion on the femtosecond time-scale. These phenomena have been studied using ultrashort optical pulses, which indirectly probe atomic positions through changes in optical properties. Because x-rays can more directly probe atomic positions, ultrashort x-ray pulses are better suited for the study of ultrafast structural dynamics. One approach towards generating ultrashort x-ray pulses is by 90° Thomson scattering between terawatt laser pulses and relativistic electrons. Using this technique, the author generated ~ 300 fs, 30 keV (0.4 Å) x-ray pulses. These x-ray pulses are absolutely synchronized with ultrashort laser pulses, allowing femtosecond optical pump/x-ray probe experiments to be performed. Using the right-angle Thomson scattering x-ray source, the author performed time-resolved x-ray diffraction studies of laser-perturbated InSb. These experiments revealed a delayed onset of lattice expansion. This delay is due to the energy relaxation from a dense electron-hole plasma to the lattice. The dense electron-hole plasma first undergoes Auger recombination, which reduces the carrier concentration while maintaining energy content. Longitudinal-optic (LO) phonon emission then couples energy to the lattice. LO phonon decay into acoustic phonons, and acoustic phonon propagation then causes the growth of a thermally expanded layer. Source characterization is instrumental in utilizing ultrashort x-ray pulses in time-resolved x-ray spectroscopies. By measurement of the electron beam diameter at the generation point, the pulse duration of the Thomson scattered x-rays is determined. Analysis of the Thomson scattered x-ray beam properties also provides a novel means of electron bunch characterization. Although the pulse duration is inferred for the Thomson scattering x-ray source, direct measurement is required for other x-ray pulse sources. A method based on the laser-assisted photoelectric effect (LAPE) has been demonstrated as a

  11. X-ray laser

    DOEpatents

    Nilsen, Joseph

    1991-01-01

    An X-ray laser (10) that lases between the K edges of carbon and oxygen, i.e. between 44 and 23 Angstroms, is provided. The laser comprises a silicon (12) and dysprosium (14) foil combination (16) that is driven by two beams (18, 20) of intense line focused (22, 24) optical laser radiation. Ground state nickel-like dysprosium ions (34) are resonantly photo-pumped to their upper X-ray laser state by line emission from hydrogen-like silicon ions (32). The novel X-ray laser should prove especially useful for the microscopy of biological specimens.

  12. X-ray superbubbles

    NASA Technical Reports Server (NTRS)

    Cash, W.

    1983-01-01

    Four regions of the galaxy, the Cygnus Superbubble, the Eta Carina complex, the Orion/Eridanus complex, and the Gum Nebula, are discussed as examples of collective effects in the interstellar medium. All four regions share certain features, indicating a common structure. The selection effects which determine the observable X-ray properties of the superbubbles are discussed, and it is demonstrated that only a very few more in our Galaxy can be detected in X rays. X-ray observation of extragalactic superbubbles is shown to be possible but requires the capabilities of a large, high quality, AXAF class observatory.

  13. Superconducting Multi-Cell Deflecting Cavity for Short-Pulse X-Ray Generation at the Advanced Photon Source

    SciTech Connect

    G.J. Waldschmidt, L.H. Morrison, R. Nassiri, R.A. Rimmer, K. Tian, H. Wang

    2009-05-01

    A superconducting multi-cell cavity for the production of short x-ray pulses at the Advanced Photon Source (APS) has been explored as an alternative to a single-cell cavity design in order to improve the packing factor and potentially reduce the number of high-power RF systems and low-level RF controls required. The cavity will operate at 2815 MHz in the APS storage ring and will require heavy damping of parasitic modes to maintain stable beam operation. Novel on-cell dampers, attached directly to the cavity body, have been utilized by taking advantage of the magnetic field null on the equatorial plane in order to enhance damping. Design issues and simulation results will be discussed.

  14. Generation and characterization of plasma channels in gas puff targets using soft X-ray radiography technique

    SciTech Connect

    Wachulak, P. W. Bartnik, A.; Jarocki, R.; Fok, T.; Węgrzyński, Ł.; Kostecki, J.; Szczurek, M.; Jabczyński, J.; Fiedorowicz, H.

    2014-10-15

    We present our recent results of a formation and characterization of plasma channels in elongated krypton and xenon gas puff targets. The study of their formation and temporal expansion was carried out using a combination of a soft X-ray radiography (shadowgraphy) and pinhole camera imaging. Two high-energy short laser pulses were used to produce the channels. When a pumping laser pulse was shaped into a line focus, using cylindrical and spherical lenses, the channels were not produced because much smaller energy density was deposited in the gas puff target. However, when a point focus was obtained, using just a spherical lens, the plasma channels appeared. The channels were up to 9 mm in length, had a quite uniform density profile, and expanded in time with velocities of about 2 cm/μs.

  15. The Wakefield Effects of Pulsed Crab Cavities at the Advanced Photon Source for Short-X-ray Pulse Generation

    SciTech Connect

    Chae, Y.-C.; Waldschmidt, G.; Dolgashev, V.; /SLAC

    2007-11-07

    In recent years we have explored the application to the Advanced Photon Source (APS) of Zholents' crab-cavity based scheme for production of short x-ray pulses. As a near-term project, the APS has elected to pursue a pulsed system using room-temperature cavities. The cavity design has been optimized to heavily damp parasitic modes while maintaining large shunt impedance for the deflecting dipole mode. We evaluated a system consisting of three crab cavities as an impedance source and determined their effect on the single- and multi-bunch instabilities. In the single-bunch instability we used the APS impedance model as the reference system in order to predict the overall performance of the ring when the crab cavities are installed in the future. For multi-bunch instabilities we used a realistic fill pattern, including hybrid-fill, and tracked multiple bunches where each bunch was treated as soft in distribution.

  16. Lumbosacral spine x-ray

    MedlinePlus

    X-ray - lumbosacral spine; X-ray - lower spine ... The test is done in a hospital x-ray department or your health care provider's office by an x-ray technician. You will be asked to lie on the x-ray table ...

  17. Thoracic spine x-ray

    MedlinePlus

    Vertebral radiography; X-ray - spine; Thoracic x-ray; Spine x-ray; Thoracic spine films; Back films ... The test is done in a hospital radiology department or in the health care provider's office. You will lie on the x-ray table in different positions. If the x-ray ...

  18. Generation-X: A large area and high angular resolution X-ray observatory to study the dawn of the universe

    NASA Astrophysics Data System (ADS)

    Zhang, W.; Petre, R.; White, N.

    In this talk we will describe the scientific and technology requirements of an X-ray observatory, called Generation-X, that is to follow the Constellation-X mission. The Generation-X mission is designed to observe the formation and evolution of the first galaxies and black holes at high redshift. To do this r quires a factor of ~1000e increased area compared to Chandra, while maintaining an angular resolution of ~ 1. The mission will determine the role of accreting black holes in the formation of structure in the early universe, which are crucial in both providing an ionizing radiation and the dynamics of galaxies formation. The Chandra mission succeeded in its prime task of solving the mystery of the X ray background, with the deep- fields showing that most, if not all, the background is the result of active galactic nuclei (AGN). This has demonstrated that X-ray surveys are an excellent tracer of accreting black holes. The Constellation-X mission will obtain detailed high resolution spectra of these faint X-ray sources. The 5-15 and 3 m2 collecting area of Constellation-X are specified to avoid confusion of these AGN, and reach flux levels of ~10-1 6 ergs/cm2 /s. To observe galaxies and black holes (as low as 10,000 solar masses) at z~10 requires telescope parameters to avoid galaxy confusion and sufficient to separate the extended galaxy emission from the nucleus. This is 50-150 m2 with an angular resolution of 0.1 to 1--- the mission parameters for Generation- X. These parameters will in a 106 -second exposure be capable of detecting sources down to a flux level of 5×10-2 0 ergs/cm2 /s and perform spectroscopic study down to 5×10-1 8 ergs/cm2 /s. With such a capability many other new science topics can be addressed, e.g. the properties of compact objects in nearby galaxies and the nature of the intergalactic mediu m at high redshift. The enabling technology for this mission is lightweight precision optics, which is beyond our existing capabilities, but will

  19. X-rays from intermediate mass stars

    NASA Astrophysics Data System (ADS)

    Robrade, Jan

    I will review the X-ray properties of intermediate mass stars and discuss possible X-ray generating mechanisms. Main-sequence stars of spectral type mid B to mid A neither drive sufficiently strong winds to produce shock generated X-rays, nor possess an outer convection zone to generate dynamo driven magnetic activity and coronae. Consequently they should be virtually X-ray dark and occasionally detected X-ray emission was usually attributed to undetected low-mass companions. However, in magnetic intermediate mass stars, the Ap/Bp stars, a different X-ray production mechanism may operate. It is termed the magnetically channeled wind-shock model, where the stellar wind from both hemispheres is channelled towards the equatorial plane, collides and forms a rigidly rotating disk around the star. The strong shocks of the nearly head-on wind collision as well as the existence of magnetically confined plasma in a dynamic circumstellar disk can lead to diverse X-ray phenomena. In this sense Ap/Bp stars bridge the 'classical' X-ray regimes of cool and hot stars.

  20. X-ray - skeleton

    MedlinePlus

    ... medlineplus.gov/ency/article/003381.htm X-ray - skeleton To use the sharing features on this page, ... ray views may be uncomfortable. If the whole skeleton is being imaged, the test usually takes 1 ...

  1. X-rays and magnetism.

    PubMed

    Fischer, Peter; Ohldag, Hendrik

    2015-09-01

    Magnetism is among the most active and attractive areas in modern solid state physics because of intriguing phenomena interesting to fundamental research and a manifold of technological applications. State-of-the-art synthesis of advanced magnetic materials, e.g. in hybrid structures paves the way to new functionalities. To characterize modern magnetic materials and the associated magnetic phenomena, polarized x-rays have emerged as unique probes due to their specific interaction with magnetic materials. A large variety of spectroscopic and microscopic techniques have been developed to quantify in an element, valence and site-sensitive way properties of ferro-, ferri-, and antiferromagnetic systems, such as spin and orbital moments, and to image nanoscale spin textures and their dynamics with sub-ns time and almost 10 nm spatial resolution. The enormous intensity of x-rays and their degree of coherence at next generation x-ray facilities will open the fsec time window to magnetic studies addressing fundamental time scales in magnetism with nanometer spatial resolution. This review will give an introduction into contemporary topics of nanoscale magnetic materials and provide an overview of analytical spectroscopy and microscopy tools based on x-ray dichroism effects. Selected examples of current research will demonstrate the potential and future directions of these techniques.

  2. Cosmic x ray physics

    NASA Technical Reports Server (NTRS)

    Mccammon, Dan; Cox, D. P.; Kraushaar, W. L.; Sanders, W. T.

    1992-01-01

    This final report covers the period 1 January 1985 - 31 March 1992. It is divided into the following sections: the soft x-ray background; proportional counter and filter calibrations; sounding rocket flight preparations; new sounding rocket payload: x-ray calorimeter; and theoretical studies. Staff, publications, conference proceedings, invited talks, contributed talks, colloquia and seminars, public service lectures, and Ph. D. theses are listed.

  3. Observation of femtosecond X-ray interactions with matter using an X-ray-X-ray pump-probe scheme.

    PubMed

    Inoue, Ichiro; Inubushi, Yuichi; Sato, Takahiro; Tono, Kensuke; Katayama, Tetsuo; Kameshima, Takashi; Ogawa, Kanade; Togashi, Tadashi; Owada, Shigeki; Amemiya, Yoshiyuki; Tanaka, Takashi; Hara, Toru; Yabashi, Makina

    2016-02-09

    Resolution in the X-ray structure determination of noncrystalline samples has been limited to several tens of nanometers, because deep X-ray irradiation required for enhanced resolution causes radiation damage to samples. However, theoretical studies predict that the femtosecond (fs) durations of X-ray free-electron laser (XFEL) pulses make it possible to record scattering signals before the initiation of X-ray damage processes; thus, an ultraintense X-ray beam can be used beyond the conventional limit of radiation dose. Here, we verify this scenario by directly observing femtosecond X-ray damage processes in diamond irradiated with extraordinarily intense (∼10(19) W/cm(2)) XFEL pulses. An X-ray pump-probe diffraction scheme was developed in this study; tightly focused double-5-fs XFEL pulses with time separations ranging from sub-fs to 80 fs were used to excite (i.e., pump) the diamond and characterize (i.e., probe) the temporal changes of the crystalline structures through Bragg reflection. It was found that the pump and probe diffraction intensities remain almost constant for shorter time separations of the double pulse, whereas the probe diffraction intensities decreased after 20 fs following pump pulse irradiation due to the X-ray-induced atomic displacement. This result indicates that sub-10-fs XFEL pulses enable conductions of damageless structural determinations and supports the validity of the theoretical predictions of ultraintense X-ray-matter interactions. The X-ray pump-probe scheme demonstrated here would be effective for understanding ultraintense X-ray-matter interactions, which will greatly stimulate advanced XFEL applications, such as atomic structure determination of a single molecule and generation of exotic matters with high energy densities.

  4. X-ray Binaries

    NASA Astrophysics Data System (ADS)

    Lewin, Walter H. G.; van Paradijs, Jan; van den Heuvel, Edward Peter Jacobus

    1997-01-01

    Preface; 1. The properties of X-ray binaries, N. E. White, F. Nagase and A. N. Parmar; 2. Optical and ultraviolet observations of X-ray binaries J. van Paradijs and J. E. McClintock; 3. Black-hole binaries Y. Tanaka and W. H. G. Lewin; 4. X-ray bursts Walter H. G. Lewin, Jan Van Paradijs and Ronald E. Taam; 5. Millisecond pulsars D. Bhattacharya; 6. Rapid aperiodic variability in binaries M. van der Klis; 7. Radio properties of X-ray binaries R. M. Hjellming and X. Han; 8. Cataclysmic variable stars France Anne-Dominic Córdova; 9. Normal galaxies and their X-ray binary populations G. Fabbiano; 10. Accretion in close binaries Andrew King; 11. Formation and evolution of neutron stars and black holes in binaries F. Verbunt and E. P. J. van den Heuvel; 12. The magnetic fields of neutron stars and their evolution D. Bhattacharya and G. Srinivasan; 13. Cosmic gamma-ray bursts K. Hurley; 14. A catalogue of X-ray binaries Jan van Paradijs; 15. A compilation of cataclysmic binaries with known or suspected orbital periods Hans Ritter and Ulrich Kolb; References; Index.

  5. X-ray lasing - The diagnostics

    SciTech Connect

    Not Available

    1985-11-01

    High-sensitivity time-resolving x-ray spectrometers were developed for the Novette x-ray laser experiments to distinguish and characterize those x-rays produced by laser activity amidst all the other background radiation. In the microchannel-plate grazing-incidence spectrometer (MCPIGS) x-rays are dispersed according to wavelength by a concave grating into a curved microchannel plate, and the amplified image is mapped flat for photographic recording. Target radiation is detected between 12.5 and 27 nm with 250 ps temporal resolution, high spectral resolution (lambda/Delta lambda = 1800), and a line-radiation detection threshold of 6 x 10 to the -7th J/sr. The transmission-grating streak spectrometer (TGSS) produces an image of the x-ray laser output (with an ellipsoidal mirror) that is separated horizontally into its constituent wavelengths (with a transmission grating) and resolved vertically in time (with a streak caemra). The TGSS has a time resolution of about 40 ps, a spectral resolution of about 0.1 nm, and a collection solid angle of about 1.2 x 10 to the -4th sr.

  6. Thermal and resonance neutrons generated by various electron and X-ray therapeutic beams from medical linacs installed in polish oncological centers

    PubMed Central

    Konefał, Adam; Orlef, Andrzej; Łaciak, Marcin; Ciba, Aleksander; Szewczuk, Marek

    2012-01-01

    Background High-energy photon and electron therapeutic beams generated in medical linear accelerators can cause the electronuclear and photonuclear reactions in which neutrons with a broad energy spectrum are produced. A low-energy component of this neutron radiation induces simple capture reactions from which various radioisotopes originate and in which the radioactivity of a linac head and various objects in the treatment room appear. Aim The aim of this paper is to present the results of the thermal/resonance neutron fluence measurements during therapeutic beam emission and exemplary spectra of gamma radiation emitted by medical linac components activated in neutron reactions for four X-ray beams and for four electron beams generated by various manufacturers’ accelerators installed in typical concrete bunkers in Polish oncological centers. Materials and methods The measurements of neutron fluence were performed with the use of the induced activity method, whereas the spectra of gamma radiation from decays of the resulting radioisotopes were measured by means of a portable high-purity germanium detector set for field spectroscopy. Results The fluence of thermal neutrons as well as resonance neutrons connected with the emission of a 20 MV X-ray beam is ∼106 neutrons/cm2 per 1 Gy of a dose in water at a reference depth. It is about one order of magnitude greater than that for the 15 MV X-ray beams and about two orders of magnitude greater than for the 18–22 MeV electron beams regardless of the type of an accelerator. Conclusion The thermal as well as resonance neutron fluence depends strongly on the type and the nominal potential of a therapeutic beam. It is greater for X-ray beams than for electrons. The accelerator accessories and other large objects should not be stored in a treatment room during high-energy therapeutic beam emission to avoid their activation caused by thermal and resonance neutrons. Half-lives of the radioisotopes originating from

  7. Efficient 2(nd) and 4(th) harmonic generation of a single-frequency, continuous-wave fiber amplifier.

    PubMed

    Sudmeyer, Thomas; Imai, Yutaka; Masuda, Hisashi; Eguchi, Naoya; Saito, Masaki; Kubota, Shigeo

    2008-02-04

    We demonstrate efficient cavity-enhanced second and fourth harmonic generation of an air-cooled, continuous-wave (cw), single-frequency 1064 nm fiber-amplifier system. The second harmonic generator achieves up to 88% total external conversion efficiency, generating more than 20-W power at 532 nm wavelength in a diffraction-limited beam (M(2) < 1.05). The nonlinear medium is a critically phase-matched, 20-mm long, anti-reflection (AR) coated LBO crystal operated at 25 degrees C. The fourth harmonic generator is based on an AR-coated, Czochralski-grown beta-BaB(2)O(4) (BBO) crystal optimized for low loss and high damage threshold. Up to 12.2 W of 266-nm deep-UV (DUV) output is obtained using a 6-mm long critically phase-matched BBO operated at 40 degrees C. This power level is more than two times higher than previously reported for cw 266-nm generation. The total external conversion efficiency from the fundamental at 1064 nm to the fourth harmonic at 266 nm is >50%.

  8. Heterojunction of Zinc Blende/Wurtzite in Zn1-xCdxS Solid Solution for Efficient Solar Hydrogen Generation: X-ray Absorption/Diffraction Approaches.

    PubMed

    Hsu, Ying-Ya; Suen, Nian-Tzu; Chang, Chung-Chieh; Hung, Sung-Fu; Chen, Chi-Liang; Chan, Ting-Shan; Dong, Chung-Li; Chan, Chih-Chieh; Chen, San-Yuan; Chen, Hao Ming

    2015-10-14

    In the past decade, inorganic semiconductors have been successfully demonstrated as light absorbers in efficient solar water splitting to generate chemical fuels. Pseudobinary semiconductors Zn1-xCdxS (0≤x≤1) have exhibited a superior photocatalytic reactivity of H2 production from splitting of water by artificial solar irradiation without any metal catalysts. However, most studies had revealed that the extremely high efficiency with an optimal content of Zn1-xCdxS solid solution was determined as a result of elevating the conduction band minimum (CBM) and the width of bandgap. In addition to corresponding band structure and bandgap, the local crystal structure should be taken into account as well to determine its photocatalytic performance. Herein, we demonstrated the correlations between the photocatalytic activity and structural properties that were first studied through synchrotron X-ray diffraction and X-ray absorption spectroscopy. The crystal structure transformed from zinc blende to coexisted phases of major zinc blende and minor wurtzite phases at a critical point. The heterojunction formed by coexistence of zinc blende and wurtzite phases in the Zn1-xCdxS solid solution can significantly improve the separation and migration of photoinduced electron-hole pairs. Besides, X-ray absorption spectra and UV-vis spectra revealed that the bandgap of the Zn0.45Cd0.55S sample extended into the region of visible light because of the incorporation of Cd element in the sample. These results provided a significant progress toward the realization of the photoelectrochemical mechanism in heterojunction between zinc blende and wurtzite phases, which can effectively separate the charge-carriers and further suppress their recombination to enhance the photocatalytic reactivity.

  9. Z-Pinch Generated X-Rays in Static-Wall Hohlraum Geometry Demonstrate Potential for Indirect-Drive ICF Studies

    SciTech Connect

    Sandord, T.W.L.; Olson, R.E.; Chandler, G.A.; Hebron, D.E.; Mock, R.C.; Leeper, R.J.; Nash, T.J.; Ruggles, L.E.; Simpson, W.W.; Struve, K.W.; Vesey, R.A.; Bowers, R.L.; Matuska, W.; Peterson, D.L.; Peterson, R.R.

    1999-08-25

    Hohlraums of full ignition scale (6-mm diameter by 7-mm length) have been heated by x-rays from a z-pinch target on Z to a variety of temperatures and pulse shapes which can be used to simulate the early phases of the National Ignition Facility (NIF) temperature drive. The pulse shape is varied by changing the on-axis target of the z pinch in a static-wall-hohlraum geometry. A 2-{micro}m-thick walled Cu cylindrical target of 8-mm diameter filled with 10 mg/cm{sup 3} CH, for example, produces foot-pulse conditions of {minus}85 eV for a duration of {approximately} 10 ns, while a solid cylindrical target of 5-mm diameter and 14-mg/cm{sup 3} CH generates first-step-pulse conditions of {approximately} 122 eV for a duration of a few ns. Alternatively, reducing the hohlraum size (to 4-mm diameter by 4-mm length) with the latter target has increased the peak temperature to {approximately} 150 eV, which is characteristic of a second-step-pulse temperature. In general, the temperature T of these x-ray driven hohlraums is in agreement with the Planckian relation (T-(P/A){sup 1/4}). P is the measured x-ray input power and A is the surface area of the hohlraum. Fully-integrated 2-D radiation-hydrodynamic simulations of the z pinch and subsequent hohlraum heating show plasma densities within the useful volume of the hohlraums to be on the order of air or less.

  10. Analysis of the relative movement between mirrors and detectors for the next generation x-ray telescopes

    NASA Astrophysics Data System (ADS)

    Civitani, Marta

    2009-08-01

    Focusing X-ray telescopes with imaging capabilities, like SIMBOL-X, HEXISAT and IXO, are characterized by very long focal lengths, greater than 10m. The constraints posed by the launchers on the maximum dimensions of a payload, make necessary using alternatives to monolithic telescopes. One possibility is that the mirror and the detectors are carried by two separate spacecrafts that fly in formation. Another is placing the detector module on a bench that will be extended once in final orbit. In both the case the system will be subjected to deformation due the relative movement of the mirrors with respect to detectors. In one case the deformation will be due to the correction on the position and attitude of the detector spacecraft to maintain the formation with the mirror spacecraft, while in the other to oscillations of the detectors on the top of the bench. The aim of this work is to compare the behavior of the system in the two different configurations and to evaluate the performances of the on board metrology systems needed not to degrade the telescope angular resolution.

  11. Cross calibration of AGFA-D7 x-ray film against direct exposure film from 2 to 8.5 keV using laser generated x-rays

    SciTech Connect

    Kyrala, George A.

    2006-05-15

    Direct exposure film (DEF) is being discontinued. DEF film has been the workhorse in inertial confinement fusion (ICF) research and is used to record x-ray images and spectra. A previous search for a replacement [K. M. Chandler et al., Rev. Sci. Instrum. 76, 113111 (2005)] did not consider AGFA film. We present comparisons using the results of measurements using AGFA-D7 film, XAR, TMG, and Biomax-MS films in the same spectrometer recording a gold spectrum in the 2-4 keV range and the iron spectrum in the 5-8.5 keV range. AGFA film was found to have some unique properties useful in x-ray spectroscopy and imaging, especially when signal strength is not a concern.

  12. Cross calibration of AGFA-D7 x-ray film against direct exposure film from 2 to 8.5 keV using laser generated x-rays

    NASA Astrophysics Data System (ADS)

    Kyrala, George A.

    2006-05-01

    Direct exposure film (DEF) is being discontinued. DEF film has been the workhorse in inertial confinement fusion (ICF) research and is used to record x-ray images and spectra. A previous search for a replacement [K. M. Chandler et al., Rev. Sci. Instrum. 76, 113111 (2005)] did not consider AGFA film. We present comparisons using the results of measurements using AGFA-D7 film, XAR, TMG, and Biomax-MS films in the same spectrometer recording a gold spectrum in the 2-4keV range and the iron spectrum in the 5-8.5keV range. AGFA film was found to have some unique properties useful in x-ray spectroscopy and imaging, especially when signal strength is not a concern.

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

    NASA Astrophysics Data System (ADS)

    Zhou, Kaishang; Feng, Chao; Deng, Haixiao; Wang, Dong

    2017-01-01

    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 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.

  14. Note: On the generation of sub-300 keV flash-X-rays using rod-pinch diode: An experimental investigation

    NASA Astrophysics Data System (ADS)

    Satyanarayana, N.; Rajawat, R. K.; Basu, Shibaji; Rao, A. Durga Prasad; Mittal, K. C.

    2014-09-01

    Generation of flash X-rays (FXRs) at less than 500 keV is described with emphasis on experimental investigation. The pulser is a Tesla transformer-Water transmission line based pulsed power generator operating in double resonance mode to power a rod-pinch diode. The configuration of aspect ratio reported here falls much below the normally reported ratios for the rod-pinch diode operation. Experimental investigation at such low pulsed voltage has revealed "flowering" of the anode tip and "pitting" of the perspex window. A possible explanation in terms of Lorentz body force is discussed rather than the pinch mechanism generally suggested in literature. The experimental investigation for the FXR generation is corroborated by measuring the radiation dose using CaSO4 (Dy) thermo luminescent dosimeters.

  15. Note: On the generation of sub-300 keV flash-X-rays using rod-pinch diode: an experimental investigation.

    PubMed

    Satyanarayana, N; Rajawat, R K; Basu, Shibaji; Rao, A Durga Prasad; Mittal, K C

    2014-09-01

    Generation of flash X-rays (FXRs) at less than 500 keV is described with emphasis on experimental investigation. The pulser is a Tesla transformer-Water transmission line based pulsed power generator operating in double resonance mode to power a rod-pinch diode. The configuration of aspect ratio reported here falls much below the normally reported ratios for the rod-pinch diode operation. Experimental investigation at such low pulsed voltage has revealed "flowering" of the anode tip and "pitting" of the perspex window. A possible explanation in terms of Lorentz body force is discussed rather than the pinch mechanism generally suggested in literature. The experimental investigation for the FXR generation is corroborated by measuring the radiation dose using CaSO4 (Dy) thermo luminescent dosimeters.

  16. Note: On the generation of sub-300 keV flash-X-rays using rod-pinch diode: An experimental investigation

    SciTech Connect

    Satyanarayana, N.; Rajawat, R. K.; Basu, Shibaji; Rao, A. Durga Prasad; Mittal, K. C.

    2014-09-15

    Generation of flash X-rays (FXRs) at less than 500 keV is described with emphasis on experimental investigation. The pulser is a Tesla transformer-Water transmission line based pulsed power generator operating in double resonance mode to power a rod-pinch diode. The configuration of aspect ratio reported here falls much below the normally reported ratios for the rod-pinch diode operation. Experimental investigation at such low pulsed voltage has revealed “flowering” of the anode tip and “pitting” of the perspex window. A possible explanation in terms of Lorentz body force is discussed rather than the pinch mechanism generally suggested in literature. The experimental investigation for the FXR generation is corroborated by measuring the radiation dose using CaSO{sub 4} (Dy) thermo luminescent dosimeters.

  17. Accelerator-driven X-ray Sources

    SciTech Connect

    Nguyen, Dinh Cong

    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. Organization of the Topical Meeting on Short Wavelength Coherent Radiation: Generation and Applications (4th) Held in North Falmouth, Massachusetts

    DTIC Science & Technology

    1989-03-01

    spectrometer using coherent VUV generated by four -wave 8:30 AM (Invited Paper) sum mixing has been used to study autoionization in NO and MAI The A. C...tween n = 5, 4, and 3 excited levels are observed in a 100- ps TuC13 Capillary Discharge Plasmas as Extreme Ultraviolet laser-produced heliumlike Al plasma...Interference in Four -Wave TuC28 Gain Measurement on a 18.2-nm Carbon Recombin- Mixing, K. G. H. Baldwin. Australian National U. Constructive ation Laser

  19. Multicolor, time-gated, soft x-ray pinhole imaging of wire array and gas puff Z pinches on the Z and Saturn pulsed power generators.

    PubMed

    Jones, B; Coverdale, C A; Nielsen, D S; Jones, M C; Deeney, C; Serrano, J D; Nielsen-Weber, L B; Meyer, C J; Apruzese, J P; Clark, R W; Coleman, P L

    2008-10-01

    A multicolor, time-gated, soft x-ray pinhole imaging instrument is fielded as part of the core diagnostic set on the 25 MA Z machine [M. E. Savage et al., in Proceedings of the Pulsed Power Plasma Sciences Conference (IEEE, New York, 2007), p. 979] for studying intense wire array and gas puff Z-pinch soft x-ray sources. Pinhole images are reflected from a planar multilayer mirror, passing 277 eV photons with <10 eV bandwidth. An adjacent pinhole camera uses filtration alone to view 1-10 keV photons simultaneously. Overlaying these data provides composite images that contain both spectral as well as spatial information, allowing for the study of radiation production in dense Z-pinch plasmas. Cu wire arrays at 20 MA on Z show the implosion of a colder cloud of material onto a hot dense core where K-shell photons are excited. A 528 eV imaging configuration has been developed on the 8 MA Saturn generator [R. B. Spielman et al., and A. I. P. Conf, Proc. 195, 3 (1989)] for imaging a bright Li-like Ar L-shell line. Ar gas puff Z pinches show an intense K-shell emission from a zippering stagnation front with L-shell emission dominating as the plasma cools.

  20. Tracking Changes in Absorptivity, Stiffness, and Organic Chemical Composition in Laboratory Generated HULIS SOA using Atomic Force Microscopy and X-ray Microscopy

    NASA Astrophysics Data System (ADS)

    Hawkins, L. N.; Lemire, A.; Kong, W.

    2014-12-01

    Light absorbing organic compounds are among the many products of aqueous phase secondary organic aerosol formation. Once formed, these compounds can alter the optical and material properties of SOA in ways that impact their ability to scatter and absorb solar radiation, deliquesce and evaporate quickly during cloud cycling, and react with gas phase species such as oxidants. To quantify these effects, we have characterized the changes in UV-visible absorption, stiffness, and particle shape that occur when aqueous SOA is exposed to repeated wet-dry cycles and photooxidation. Material properties were measured with Atomic Force Microscopy of atomized laboratory generated SOA; this material was created by combining glyoxal, methylglyoxal, or glycolaldehyde with ammonium sulfate, glycine, or methylamine in solution and either spray drying or evaporating the bulk solution. In addition to optical and material properties, changes in organic functional groups were tracked using scanning transmission x-ray microscopy (STXM) of the near carbon edge x-ray absorption fine structure (NEXAFS). Photooxidation experiments of the same aqueous SOA revealed concomitant changes in the organic functional groups and light absorption spectra, along with measurable changes in particle stiffness.

  1. Clocking femtosecond X rays.

    PubMed

    Cavalieri, A L; Fritz, D M; Lee, S H; Bucksbaum, P H; Reis, D A; Rudati, J; Mills, D M; Fuoss, P H; Stephenson, G B; Kao, C C; Siddons, D P; Lowney, D P; Macphee, A G; Weinstein, D; Falcone, R W; Pahl, R; Als-Nielsen, J; Blome, C; Düsterer, S; Ischebeck, R; Schlarb, H; Schulte-Schrepping, H; Tschentscher, Th; Schneider, J; Hignette, O; Sette, F; Sokolowski-Tinten, K; Chapman, H N; Lee, R W; Hansen, T N; Synnergren, O; Larsson, J; Techert, S; Sheppard, J; Wark, J S; Bergh, M; Caleman, C; Huldt, G; van der Spoel, D; Timneanu, N; Hajdu, J; Akre, R A; Bong, E; Emma, P; Krejcik, P; Arthur, J; Brennan, S; Gaffney, K J; Lindenberg, A M; Luening, K; Hastings, J B

    2005-03-25

    Linear-accelerator-based sources will revolutionize ultrafast x-ray science due to their unprecedented brightness and short pulse duration. However, time-resolved studies at the resolution of the x-ray pulse duration are hampered by the inability to precisely synchronize an external laser to the accelerator. At the Sub-Picosecond Pulse Source at the Stanford Linear-Accelerator Center we solved this problem by measuring the arrival time of each high energy electron bunch with electro-optic sampling. This measurement indirectly determined the arrival time of each x-ray pulse relative to an external pump laser pulse with a time resolution of better than 60 fs rms.

  2. Simulation of ultraviolet- and soft X-ray-pulse generation as a result of cooperative recombination of excitons in diamond nanocrystals embedded in a polymer film

    SciTech Connect

    Kukushkin, V. A.

    2013-11-15

    Using numerical simulation, it is shown that the recombination of free excitons photoexcited in diamond nanocrystals embedded in a polymer film can occur in the cooperative mode. It is found that this mode can be implemented despite the fact that diamond is an 'indirect' semiconductor. It is shown that the power of the generated radiation at the pulse peak during the cooperative recombination of free excitons can exceed that of the incoherent spontaneous emission of the same initial number of free excitons by more than an order of magnitude. Finally, it is shown that the process under consideration can be used to generate picosecond pulses of ultraviolet and soft X-ray electromagnetic field at a wavelength of 235 nm.

  3. Analysis of x-ray spectrum obtained in electron cyclotron resonance x-ray source

    SciTech Connect

    Baskaran, R.; Selvakumaran, T.S.; Sunil Sunny, C.

    2006-03-15

    The analysis of the x-ray spectrum obtained in electron cyclotron resonance (ECR) x-ray source is carried out. Assuming single-particle motion, the electron acceleration and its final energy are calculated for TE{sub 111} cylindrical cavity field and uniform external dc magnetic field. In the calculation, initial coordinates of 40 000 electrons were uniformly selected over the central plane of the cavity using random number generator. The final energy of each electron when it hits the wall is stored and the electron energy distribution is obtained. Using the general purpose Monte Carlo N-particle transport code version 4A, the geometry of the ECR x-ray source is modeled. The x-ray energy spectrum is calculated for the geometry model and the numerically calculated electron energy distribution. The calculated x-ray spectrum is compared with the experimentally measured x-ray spectrum.

  4. Behavior of characteristic X-rays from a partial-transmission-type X-ray target.

    PubMed

    Raza, Hamid Saeed; Kim, Hyun Jin; Ha, Jun Mok; Cho, Sung Oh

    2013-10-01

    The angular distribution of characteristic X-rays using a partial-transmission tungsten target was analyzed. Twenty four tallies were modeled to cover a 360° envelope around the target. The Monte Carlo N-Particle (MCNP5) simulation results revealed that the characteristic X-ray flux is not always isotropic around the target. Rather, the flux mainly depends on the target thickness and the energy of the incident electron beam. A multi-energy photon generator is proposed to emit high-energy characteristic X-rays, where the target acts as a filter for the low-energy characteristic X-rays.

  5. Microgap x-ray detector

    DOEpatents

    Wuest, C.R.; Bionta, R.M.; Ables, E.

    1994-05-03

    An x-ray detector is disclosed which provides for the conversion of x-ray photons into photoelectrons and subsequent amplification of these photoelectrons through the generation of electron avalanches in a thin gas-filled region subject to a high electric potential. The detector comprises a cathode (photocathode) and an anode separated by the thin, gas-filled region. The cathode may comprise a substrate, such a beryllium, coated with a layer of high atomic number material, such as gold, while the anode can be a single conducting plane of material, such as gold, or a plane of resistive material, such as chromium/silicon monoxide, or multiple areas of conductive or resistive material, mounted on a substrate composed of glass, plastic or ceramic. The charge collected from each electron avalanche by the anode is passed through processing electronics to a point of use, such as an oscilloscope. 3 figures.

  6. Microgap x-ray detector

    DOEpatents

    Wuest, Craig R.; Bionta, Richard M.; Ables, Elden

    1994-01-01

    An x-ray detector which provides for the conversion of x-ray photons into photoelectrons and subsequent amplification of these photoelectrons through the generation of electron avalanches in a thin gas-filled region subject to a high electric potential. The detector comprises a cathode (photocathode) and an anode separated by the thin, gas-filled region. The cathode may comprise a substrate, such a beryllium, coated with a layer of high atomic number material, such as gold, while the anode can be a single conducting plane of material, such as gold, or a plane of resistive material, such as chromium/silicon monoxide, or multiple areas of conductive or resistive material, mounted on a substrate composed of glass, plastic or ceramic. The charge collected from each electron avalanche by the anode is passed through processing electronics to a point of use, such as an oscilloscope.

  7. Probing ultra-fast processes with high dynamic range at 4th-generation light sources: Arrival time and intensity binning at unprecedented repetition rates

    PubMed Central

    Kovalev, S.; Green, B.; Golz, T.; Maehrlein, S.; Stojanovic, N.; Fisher, A. S.; Kampfrath, T.; Gensch, M.

    2017-01-01

    Understanding dynamics on ultrafast timescales enables unique and new insights into important processes in the materials and life sciences. In this respect, the fundamental pump-probe approach based on ultra-short photon pulses aims at the creation of stroboscopic movies. Performing such experiments at one of the many recently established accelerator-based 4th-generation light sources such as free-electron lasers or superradiant THz sources allows an enormous widening of the accessible parameter space for the excitation and/or probing light pulses. Compared to table-top devices, critical issues of this type of experiment are fluctuations of the timing between the accelerator and external laser systems and intensity instabilities of the accelerator-based photon sources. Existing solutions have so far been only demonstrated at low repetition rates and/or achieved a limited dynamic range in comparison to table-top experiments, while the 4th generation of accelerator-based light sources is based on superconducting radio-frequency technology, which enables operation at MHz or even GHz repetition rates. In this article, we present the successful demonstration of ultra-fast accelerator-laser pump-probe experiments performed at an unprecedentedly high repetition rate in the few-hundred-kHz regime and with a currently achievable optimal time resolution of 13 fs (rms). Our scheme, based on the pulse-resolved detection of multiple beam parameters relevant for the experiment, allows us to achieve an excellent sensitivity in real-world ultra-fast experiments, as demonstrated for the example of THz-field-driven coherent spin precession. PMID:28382317

  8. Probing ultra-fast processes with high dynamic range at 4th-generation light sources: Arrival time and intensity binning at unprecedented repetition rates.

    PubMed

    Kovalev, S; Green, B; Golz, T; Maehrlein, S; Stojanovic, N; Fisher, A S; Kampfrath, T; Gensch, M

    2017-03-01

    Understanding dynamics on ultrafast timescales enables unique and new insights into important processes in the materials and life sciences. In this respect, the fundamental pump-probe approach based on ultra-short photon pulses aims at the creation of stroboscopic movies. Performing such experiments at one of the many recently established accelerator-based 4th-generation light sources such as free-electron lasers or superradiant THz sources allows an enormous widening of the accessible parameter space for the excitation and/or probing light pulses. Compared to table-top devices, critical issues of this type of experiment are fluctuations of the timing between the accelerator and external laser systems and intensity instabilities of the accelerator-based photon sources. Existing solutions have so far been only demonstrated at low repetition rates and/or achieved a limited dynamic range in comparison to table-top experiments, while the 4th generation of accelerator-based light sources is based on superconducting radio-frequency technology, which enables operation at MHz or even GHz repetition rates. In this article, we present the successful demonstration of ultra-fast accelerator-laser pump-probe experiments performed at an unprecedentedly high repetition rate in the few-hundred-kHz regime and with a currently achievable optimal time resolution of 13 fs (rms). Our scheme, based on the pulse-resolved detection of multiple beam parameters relevant for the experiment, allows us to achieve an excellent sensitivity in real-world ultra-fast experiments, as demonstrated for the example of THz-field-driven coherent spin precession.

  9. Parametric X-rays at FAST

    SciTech Connect

    Sen, Tanaji

    2016-06-01

    We discuss the generation of parametric X-rays (PXR) in the photoinjector at the new FAST facility at Fermilab. Detailed calculations of the intensity spectrum, energy and angular widths and spectral brilliance with a diamond crystal are presented. We also report on expected results with PXR generated while the beam is channeling. The low emittance electron beam makes this facility a promising source for creating brilliant X-rays.

  10. Quantitative Measurements of X-ray Intensity

    SciTech Connect

    Haugh, M. J., Schneider, M.

    2011-09-01

    This chapter describes the characterization of several X-ray sources and their use in calibrating different types of X-ray cameras at National Security Technologies, LLC (NSTec). The cameras are employed in experimental plasma studies at Lawrence Livermore National Laboratory (LLNL), including the National Ignition Facility (NIF). The sources provide X-rays in the energy range from several hundred eV to 110 keV. The key to this effort is measuring the X-ray beam intensity accurately and traceable to international standards. This is accomplished using photodiodes of several types that are calibrated using radioactive sources and a synchrotron source using methods and materials that are traceable to the U.S. National Institute of Standards and Technology (NIST). The accreditation procedures are described. The chapter begins with an introduction to the fundamental concepts of X-ray physics. The types of X-ray sources that are used for device calibration are described. The next section describes the photodiode types that are used for measuring X-ray intensity: power measuring photodiodes, energy dispersive photodiodes, and cameras comprising photodiodes as pixel elements. Following their description, the methods used to calibrate the primary detectors, the power measuring photodiodes and the energy dispersive photodiodes, as well as the method used to get traceability to international standards are described. The X-ray source beams can then be measured using the primary detectors. The final section then describes the use of the calibrated X-ray beams to calibrate X-ray cameras. Many of the references are web sites that provide databases, explanations of the data and how it was generated, and data calculations for specific cases. Several general reference books related to the major topics are included. Papers expanding some subjects are cited.

  11. X-ray fluorescence experiment

    NASA Technical Reports Server (NTRS)

    Adler, I.; Trombka, J. I.; Gerard, J.; Schmadebeck, R.; Lowman, P.; Blodgett, H.; Yin, L.; Eller, E.; Lamothe, R.; Gorenstein, P.

    1972-01-01

    The preliminary results from the Sco X-1 and Cyg X-1 obtained from the Apollo 15 X-ray detector data are presented along with preliminary results of the X-ray fluorescence spectrometric data of the lunar surface composition. The production of the characteristic X-rays following the interaction of solar X-rays with the lunar surface is described along with the X-ray spectrometer. Preliminary analyses of the astronomical X-ray observation and the X-ray fluorescence data are presented.

  12. Toward Adaptive X-Ray Telescopes

    NASA Technical Reports Server (NTRS)

    O'Dell, Stephen L.; Atkins, Carolyn; Button, Tim W.; Cotroneo, Vincenzo; Davis, William N.; Doel, Peer; Feldman, Charlotte H.; Freeman, Mark D.; Gubarev, Mikhail V.; Kolodziejczak, Jeffrey J.; Michette, Alan G.; Ramsey, Brian D.; Reid, Paul B.; Rodriguez Sanmartin, Daniel; Saha, Timo T.; Schwartz, Daniel A.; Trolier-McKinstry, Susan; Wilke, Rudeger H. T.; Willingale, Richard; Zhang, William W.

    2011-01-01

    Future x-ray observatories will require high-resolution (less than 1 inch) optics with very-large-aperture (greater than 25 square meter) areas. Even with the next generation of heavy-lift launch vehicles, launch-mass constraints and aperture-area requirements will limit the surface areal density of the grazing-incidence mirrors to about 1 kilogram per square meter or less. Achieving sub-arcsecond x-ray imaging with such lightweight mirrors will require excellent mirror surfaces, precise and stable alignment, and exceptional stiffness or deformation compensation. Attaining and maintaining alignment and figure control will likely involve adaptive (in-space adjustable) x-ray optics. In contrast with infrared and visible astronomy, adaptive optics for x-ray astronomy is in its infancy. In the middle of the past decade, two efforts began to advance technologies for adaptive x-ray telescopes: The Generation-X (Gen-X) concept studies in the United States, and the Smart X-ray Optics (SXO) Basic Technology project in the United Kingdom. This paper discusses relevant technological issues and summarizes progress toward adaptive x-ray telescopes.

  13. Toward active x-ray telescopes

    NASA Astrophysics Data System (ADS)

    O'Dell, Stephen L.; Atkins, Carolyn; Button, Timothy W.; Cotroneo, Vincenzo; Davis, William N.; Doel, Peter; Feldman, Charlotte H.; Freeman, Mark D.; Gubarev, Mikhail V.; Kolodziejczak, Jeffery J.; Michette, Alan G.; Ramsey, Brian D.; Reid, Paul B.; Rodriguez Sanmartin, Daniel; Saha, Timo T.; Schwartz, Daniel A.; Trolier-McKinstry, Susan; Wilke, Rudeger H. T.; Willingale, Richard; Zhang, William W.

    2011-09-01

    Future x-ray observatories will require high-resolution (< 1") optics with very-large-aperture (> 25 m2) areas. Even with the next generation of heavy-lift launch vehicles, launch-mass constraints and aperture-area requirements will limit the areal density of the grazing-incidence mirrors to about 1 kg/m2 or less. Achieving sub-arcsecond x-ray imaging with such lightweight mirrors will require excellent mirror surfaces, precise and stable alignment, and exceptional stiffness or deformation compensation. Attaining and maintaining alignment and figure control will likely involve active (in-space adjustable) x-ray optics. In contrast with infrared and visible astronomy, active optics for x-ray astronomy is in its infancy. In the middle of the past decade, two efforts began to advance technologies for adaptive x-ray telescopes: The Smart X-ray Optics (SXO) Basic Technology project in the United Kingdom (UK) and the Generation-X (Gen-X) concept studies in the United States (US). This paper discusses relevant technological issues and summarizes progress toward active x-ray telescopes.

  14. The X-ray binary, UW CMa

    NASA Technical Reports Server (NTRS)

    Heap, S. R.

    1982-01-01

    The UW CMa is a close, eclipsing binary composed of an O7f primary with a stron wind and a less luminous O-type companion. It was found that UW CMa a variable X-ray source, whose X-ray variations are in phase with its optical light curve. Since both components of the binary system are O stars, accretion by a compact object is ruled out as a mechanism for generating X-rays. The UW CMa represents a new class of X-ray binaries, in which X-rays result from the collision of a wind from one star with the surface or wind of the other star. It is hypothesised that the impact of a wind against a star generates a shock wave about 0.25 stellar radii above the stellar surface, and material behind the shock front, heated to bout 10 million degrees, radiates the X-ray apparent X-ray variability is due to its location between the two stars, where it undergoes eclipses. The high temperature region maintains an ionization cavity in the wind, as detected with IUE. The ionization cavity is the source of depletion of absorbing ions in the wind between the two stars.

  15. X-ray beam finder

    DOEpatents

    Gilbert, H.W.

    1983-06-16

    An X-ray beam finder for locating a focal spot of an X-ray tube includes a mass of X-ray opaque material having first and second axially-aligned, parallel-opposed faces connected by a plurality of substantially identical parallel holes perpendicular to the faces and a film holder for holding X-ray sensitive film tightly against one face while the other face is placed in contact with the window of an X-ray head.

  16. 21 CFR 1020.40 - Cabinet x-ray systems.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... electron microscope equipment or to systems for intentional exposure of humans to x-rays. (b) Definitions... electrons (negatrons and positrons) liberated by photons in a volume element of air having mass dm are... assemblage of components for the controlled generation of x-rays. (13) X-ray tube means any electron...

  17. 21 CFR 1020.40 - Cabinet x-ray systems.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... electron microscope equipment or to systems for intentional exposure of humans to x-rays. (b) Definitions... electrons (negatrons and positrons) liberated by photons in a volume element of air having mass dm are... assemblage of components for the controlled generation of x-rays. (13) X-ray tube means any electron...

  18. 21 CFR 1020.40 - Cabinet x-ray systems.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... electron microscope equipment or to systems for intentional exposure of humans to x-rays. (b) Definitions... electrons (negatrons and positrons) liberated by photons in a volume element of air having mass dm are... assemblage of components for the controlled generation of x-rays. (13) X-ray tube means any electron...

  19. 21 CFR 1020.40 - Cabinet x-ray systems.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... electron microscope equipment or to systems for intentional exposure of humans to x-rays. (b) Definitions... electrons (negatrons and positrons) liberated by photons in a volume element of air having mass dm are... assemblage of components for the controlled generation of x-rays. (13) X-ray tube means any electron...

  20. External focusing of nanosecond pulsed X-ray radiation

    NASA Astrophysics Data System (ADS)

    Begidov, A. A.; Fursey, G. N.; Polyakov, M. A.

    2016-02-01

    The feasibility of efficient focusing of high-power pulsed X-ray radiation generated by explosive electron emission from carbon nanoclusters is shown by direct experiments with the use of polycapillary X-ray optics. It is shown that the X-ray spot in the focus of the polycapillary lens can be reduced to 1/20 of its initial size.

  1. X-ray shadowgraphing in laser-produced plasma experiments.

    PubMed

    VanHulsteyn, D B; Benjamin, R F

    1977-08-01

    We discuss a design for an x-ray framing camera. Shadowgraphing experiments using a laser-generated x-ray source demonstrate that 5-microm spatial resolution can be obtained for this camera with less than 7 J of laser energy to produce the x-ray source.

  2. Neck x-ray

    MedlinePlus

    ... look at cervical vertebrae. These are the 7 bones of the spine in the neck. ... A neck x-ray can detect: Bone joint that is out of position (dislocation) Breathing in a foreign object Broken bone (fracture) Disk problems (disks ...

  3. Abdominal x-ray

    MedlinePlus

    ... a kidney stone Identify blockage in the intestine Locate an object that has been swallowed Help diagnose diseases, such as tumors or other conditions Normal Results The x-ray will show normal structures for a person your age. What Abnormal Results Mean Abnormal findings ...

  4. Large Area X-Ray Spectroscopy Mission

    NASA Technical Reports Server (NTRS)

    Tananbaum, H.

    1997-01-01

    The Large Area X-ray Spectroscopy (LAXS) mission concept study continues to evolve strongly following the merging of the LAXS mission with the Next Generation X-ray Observatory (NGXO, PI: Nick White) into the re-named High Throughput X-ray Spectroscopy (HTXS) Mission. HTXS retains key elements of the LAXS proposal, including the use of multiple satellites for risk-reduction and cost savings. A key achievement of the program has been the recommendation by the Structure and Evolution of the Universe (SEUS) (April 1997) for a new start for the HTXS mission in the 2000-2004 timeframe.

  5. TU-A-9A-07: X-Ray Acoustic Computed Tomography (XACT): 100% Sensitivity to X-Ray Absorption

    SciTech Connect

    Xiang, L; Ahmad, M; Nikoozadeh, A; Pratx, G; Khuri-Yakub, B; Xing, L

    2014-06-15

    Purpose: To assess whether X-ray acoustic computed tomography (XACT) is more sensitive to X-ray absorption than that of the conventional X-ray imaging. Methods: First, a theoretical model was built to analyze the X-ray absorption sensitivity of XACT imaging and conventional X-ray imaging. Second, an XACT imaging system was developed to evaluate the X-ray induced acoustic signal generation as well as the sensitivity improvement over transmission x-ray imaging. Ultra-short x-ray pulses (60-nanosecond) were generated from an X-ray source operated at the energy of 150 kVp with a 10-Hz repetition rate. The X-ray pulse was synchronized with the acoustic detection via a x-ray scintillation triggering to acquire the X-ray induced acoustic signal. Results: Theoretical analysis shows that X-ray induced acoustic signal is sensitive only to the X-ray absorption, while completely insensitive to out the X-ray scattering and fluorescence. XACT has reduced background and increased contrast-to-noise ratio, and therefore has increased sensitivity compared to transmission x-ray imaging. For a 50-μm size, gadolinium insertion in tissue exposed to 40 keV X-rays; the sensitivity of XACT imaging is about 28.9 times higher than that of conventional X-ray imaging. Conclusion: X-ray acoustic computer tomography (XACT) as a new imaging modality combines X-ray absorption contrast and high ultrasonic resolution in a single modality. It is feasible to improve the imaging sensitivity with XACT imaging compared with conventional X-ray imaging. Taking advantage of the high ultrasonic resolution, it is possible to perform 3-D imaging with a single x-ray pulse with arrays of transducers without any mechanical motion of the imaging system. This single-shot capability offers the potential of reducing radiation dose by a factor of 1000, and imaging 100 times faster when compared to the conventional X-ray CT, and thus revolutionizing x-ray imaging applications in medicine and biology. The authors

  6. Fabrication of large area X-ray diffraction grating for X-ray phase imaging

    SciTech Connect

    Noda, Daiji; Tokuoka, Atsushi; Katori, Megumi; Minamiyama, Yasuto; Yamashita, Kenji; Nishida, Satoshi; Hattori, Tadashi

    2012-07-31

    X-ray lithography, which uses highly directional synchrotron radiation, is one of the technologies that can be used for fabricating micrometer-sized structures. In X-ray lithography, the accuracy of the fabricated structure depends largely on the accuracy of the X-ray mask. Since X-ray radiation is highly directional, a micro-fabrication technology that produces un-tapered and high aspect ratio highly absorbent structures on a low absorbent membrane is required. Conventionally, a resin material is used as the support membrane for large area X-ray masks. However, resin membranes have the disadvantage that they can sag after several cycles of X-ray exposure due to the heat generated by the X-rays. Therefore, we proposed and used thin carbon wafers for the membrane material because carbon has an extremely small thermal expansion coefficient. We fabricated new carbon membrane X-ray masks, and these results of X-ray lithography demonstrate the superior performance.

  7. X-ray induced singlet oxygen generation by nanoparticle-photosensitizer conjugates for photodynamic therapy: determination of singlet oxygen quantum yield

    NASA Astrophysics Data System (ADS)

    Clement, Sandhya; Deng, Wei; Camilleri, Elizabeth; Wilson, Brian C.; Goldys, Ewa M.

    2016-01-01

    Singlet oxygen is a primary cytotoxic agent in photodynamic therapy. We show that CeF3 nanoparticles, pure as well as conjugated through electrostatic interaction with the photosensitizer verteporfin, are able to generate singlet oxygen as a result of UV light and 8 keV X-ray irradiation. The X-ray stimulated singlet oxygen quantum yield was determined to be 0.79 ± 0.05 for the conjugate with 31 verteporfin molecules per CeF3 nanoparticle, the highest conjugation level used. From this result we estimate the singlet oxygen dose generated from CeF3-verteporfin conjugates for a therapeutic dose of 60 Gy of ionizing radiation at energies of 6 MeV and 30 keV to be (1.2 ± 0.7) × 108 and (2.0 ± 0.1) × 109 singlet oxygen molecules per cell, respectively. These are comparable with cytotoxic doses of 5 × 107-2 × 109 singlet oxygen molecules per cell reported in the literature for photodynamic therapy using light activation. We confirmed that the CeF3-VP conjugates enhanced cell killing with 6 MeV radiation. This work confirms the feasibility of using X- or γ- ray activated nanoparticle-photosensitizer conjugates, either to supplement the radiation treatment of cancer, or as an independent treatment modality.

  8. X-ray induced singlet oxygen generation by nanoparticle-photosensitizer conjugates for photodynamic therapy: determination of singlet oxygen quantum yield

    PubMed Central

    Clement, Sandhya; Deng, Wei; Camilleri, Elizabeth; Wilson, Brian C.; Goldys, Ewa M.

    2016-01-01

    Singlet oxygen is a primary cytotoxic agent in photodynamic therapy. We show that CeF3 nanoparticles, pure as well as conjugated through electrostatic interaction with the photosensitizer verteporfin, are able to generate singlet oxygen as a result of UV light and 8 keV X-ray irradiation. The X-ray stimulated singlet oxygen quantum yield was determined to be 0.79 ± 0.05 for the conjugate with 31 verteporfin molecules per CeF3 nanoparticle, the highest conjugation level used. From this result we estimate the singlet oxygen dose generated from CeF3-verteporfin conjugates for a therapeutic dose of 60 Gy of ionizing radiation at energies of 6 MeV and 30 keV to be (1.2 ± 0.7) × 108 and (2.0 ± 0.1) × 109 singlet oxygen molecules per cell, respectively. These are comparable with cytotoxic doses of 5 × 107–2 × 109 singlet oxygen molecules per cell reported in the literature for photodynamic therapy using light activation. We confirmed that the CeF3-VP conjugates enhanced cell killing with 6 MeV radiation. This work confirms the feasibility of using X- or γ- ray activated nanoparticle-photosensitizer conjugates, either to supplement the radiation treatment of cancer, or as an independent treatment modality. PMID:26818819

  9. X-ray induced singlet oxygen generation by nanoparticle-photosensitizer conjugates for photodynamic therapy: determination of singlet oxygen quantum yield.

    PubMed

    Clement, Sandhya; Deng, Wei; Camilleri, Elizabeth; Wilson, Brian C; Goldys, Ewa M

    2016-01-28

    Singlet oxygen is a primary cytotoxic agent in photodynamic therapy. We show that CeF3 nanoparticles, pure as well as conjugated through electrostatic interaction with the photosensitizer verteporfin, are able to generate singlet oxygen as a result of UV light and 8 keV X-ray irradiation. The X-ray stimulated singlet oxygen quantum yield was determined to be 0.79 ± 0.05 for the conjugate with 31 verteporfin molecules per CeF3 nanoparticle, the highest conjugation level used. From this result we estimate the singlet oxygen dose generated from CeF3-verteporfin conjugates for a therapeutic dose of 60 Gy of ionizing radiation at energies of 6 MeV and 30 keV to be (1.2 ± 0.7) × 10(8) and (2.0 ± 0.1) × 10(9) singlet oxygen molecules per cell, respectively. These are comparable with cytotoxic doses of 5 × 10(7)-2 × 10(9) singlet oxygen molecules per cell reported in the literature for photodynamic therapy using light activation. We confirmed that the CeF3-VP conjugates enhanced cell killing with 6 MeV radiation. This work confirms the feasibility of using X- or γ- ray activated nanoparticle-photosensitizer conjugates, either to supplement the radiation treatment of cancer, or as an independent treatment modality.

  10. X-Ray Background from Early Binaries

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-11-01

    What impact did X-rays from the first binary star systems have on the universe around them? A new study suggests this radiation may have played an important role during the reionization of our universe.Ionizing the UniverseDuring the period of reionization, the universe reverted from being neutral (as it was during recombination, the previous period)to once again being ionized plasma a state it has remained in since then. This transition, which occurred between 150 million and one billion years after the Big Bang (redshift of 6 z 20), was caused by the formation of the first objects energetic enough to reionize the universes neutral hydrogen.ROSAT image of the soft X-ray background throughout the universe. The different colors represent different energy bands: 0.25 keV (red), 0.75 keV (green), 1.5 keV (blue). [NASA/ROSAT Project]Understanding this time period in particular, determining what sources caused the reionization, and what the properties were of the gas strewn throughout the universe during this time is necessary for us to be able to correctly interpret cosmological observations.Conveniently, the universe has provided us with an interesting clue: the large-scale, diffuse X-ray background we observe all around us. What produced these X-rays, and what impact did this radiation have on the intergalactic medium long ago?The First BinariesA team of scientists led by Hao Xu (UC San Diego) has suggested that the very first generation of stars might be an important contributor to these X-rays.This hypothetical first generation, Population III stars, are thought to have formed before and during reionization from large clouds of gas containing virtually no metals. Studies suggest that a large fraction of Pop III stars formed in binaries and when those stars ended their lives as black holes, ensuing accretion from their companions could produceX-ray radiation.The evolution with redshift of the mean X-ray background intensities. Each curve represents a different

  11. Galaxies in the X-ray Band

    NASA Technical Reports Server (NTRS)

    Hornschemeier, Ann

    2008-01-01

    This talk will provide a brief review of progress on X-ray emission from normal (non-AGN) galaxy populations, including important constraints on the evolution of accreting binary populations over important cosmological timescales. We will also look to the future, anticipating constraints from near-term imaging hard X-ray missions such as NuSTAR, Simbol-X and NeXT and then the longer-term prospects for studying galaxies with the Generation-X mission.

  12. Galaxies in the X-Ray Band

    NASA Technical Reports Server (NTRS)

    Hornschemeier, Ann

    2008-01-01

    This talk will provide a brief review of progress an X-ray emission from normal (non-AGN) galaxy populations, including important constraints on the evolution of accreting binary populations over important cosmological timescales. We will also look to the future, anticipating constraints from near-term imaging hard X-ray missions such as NuSTAR, Simbol-X and NeXT and then the longer-term prospects for studying galaxies with the Generation-X mission,

  13. A laser-plasma-produced soft X-ray laser at 89 eV generates DNA double-strand breaks in human cancer cells.

    PubMed

    Sato, Katsutoshi; Nishikino, Masaharu; Kawachi, Tetsuya; Shimokawa, Takashi; Imai, Takashi; Teshima, Teruki; Nishimura, Hiroaki; Kando, Masaki

    2015-07-01

    While it has been expected that X-ray laser will be widely applied to biomedical studies, this has not been achieved to date and its biological effects such as DNA damage have not been evaluated. As a first step for its biological application, we developed a culture cell irradiation system, particularly designed for a plasma-driven soft X-ray laser pulse, to investigate whether the soft X-ray laser is able to induce DNA double strand breaks (DSBs) in living cells or not. The human adenocarcimona cell line A549 was irradiated with the soft X-ray laser at a photon energy of 89 eV and the repair focus formation of the DSBs was assessed by immunofluorescence staining with antiphosphorylated DNA-PKcs (p-DNA-PKcs), ATM (p-ATM) and γ-H2AX antibody. The p-DNA-PKcs, ATM, and γ-H2AX foci were clearly identified after soft X-ray laser irradiation. Furthermore, the increase in the X-ray laser shot number, even from a single shot, results in the increase in p-DNA-PKcs foci. These results are the first evidence that the 89 eV soft X-ray laser is able to induce DSB in living cells. Our study demonstrated that this irradiation system is a useful tool for investigating the radiobiological effect of soft X-ray laser.

  14. X-ray safety at the Los Alamos National Laboratory

    SciTech Connect

    Gutierrez, J.A.

    1986-11-01

    An organized and structured safety program for x-ray generating devices was initiated in October, 1979. An X-ray Device Control Office was established to manage the program that currently oversees the activities of 201 x-ray generating devices and to provide SOP reviews, perform shielding calculations, and provide training for both the operators and health physics x-ray device surveyors. The new program also establishes controls for procurement of new equipment, requires the writing of Standard Operating Procedures, requires training for operators and provides routine and non-routine safety inspections of x-ray generating devices. Prior to this program going into effect, the Laboratory had recorded nine documented x-ray related exposure accidents. Since then, there have been none. Program elements and experiences of interest to other x-ray device users are discussed. 3 refs.

  15. X-Ray Astronomy

    NASA Technical Reports Server (NTRS)

    Wu, S. T.

    2000-01-01

    Dr. S. N. Zhang has lead a seven member group (Dr. Yuxin Feng, Mr. XuejunSun, Mr. Yongzhong Chen, Mr. Jun Lin, Mr. Yangsen Yao, and Ms. Xiaoling Zhang). This group has carried out the following activities: continued data analysis from space astrophysical missions CGRO, RXTE, ASCA and Chandra. Significant scientific results have been produced as results of their work. They discovered the three-layered accretion disk structure around black holes in X-ray binaries; their paper on this discovery is to appear in the prestigious Science magazine. They have also developed a new method for energy spectral analysis of black hole X-ray binaries; four papers on this topics were presented at the most recent Atlanta AAS meeting. They have also carried Monte-Carlo simulations of X-ray detectors, in support to the hardware development efforts at Marshall Space Flight Center (MSFC). These computation-intensive simulations have been carried out entirely on the computers at UAH. They have also carried out extensive simulations for astrophysical applications, taking advantage of the Monte-Carlo simulation codes developed previously at MSFC and further improved at UAH for detector simulations. One refereed paper and one contribution to conference proceedings have been resulted from this effort.

  16. X-Ray Vision

    NASA Technical Reports Server (NTRS)

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

    2004-01-01

    We are fabricating optics for the hard-x-ray region using electroless nickel replication. The attraction of this process, which has been widely used elsewhere, is that the resulting full shell optics are inherently stable and thus can have very good angular resolution. The challenge with this process is to develop lightweight optics (nickel has a relatively high density of 8.9 g/cu cm), and to keep down the costs of mandrel fabrication. We accomplished the former through the development of high-strength nickel alloys that permit very thin shells without fabrication- and handling-induced deformations. For the latter, we have utilized inexpensive grinding and diamond turning to figure the mandrels and then purpose-built polishing machines to finish the surface. In-house plating tanks and a simple water-bath separation system complete the process. To date we have built shells ranging in size from 5 cm diameter to 50 cm, and with thickness down to 100 micron. For our HERO balloon program, we are fabricating over 200 iridium-coated shells, 250 microns thick, for hard-x-ray imaging up to 75 keV. Early test results on these have indicated half-power-diameters of 15 arcsec. The status of these and other hard-x-ray optics will be reviewed.

  17. X-ray Spectrometer

    NASA Technical Reports Server (NTRS)

    Porter, F. Scott

    2004-01-01

    The X-ray Spectrometer (XRS) instrument is a revolutionary non-dispersive spectrometer that will form the basis for the Astro-E2 observatory to be launched in 2005. We have recently installed a flight spare X R S microcalorimeter spectrometer at the EBIT-I facility at LLNL replacing the XRS from the earlier Astro-E mission and providing twice the resolution. The X R S microcalorimeter is an x-ray detector that senses the heat deposited by the incident photon. It achieves a high energy resolution by operating at 0.06K and by carefully controlling the heat capacity and thermal conductance. The XRS/EBIT instrument has 32 pixels in a square geometry and achieves an energy resolution of 6 eV at 6 keV, with a bandpass from 0.1 to 12 keV (or more at higher operating temperature). The instrument allows detailed studies of the x-ray line emission of laboratory plasmas. The XRS/EBIT also provides an extensive calibration "library" for the Astro-E2 observatory.

  18. X-ray lithography masking

    NASA Technical Reports Server (NTRS)

    Smith, Henry I. (Inventor); Lim, Michael (Inventor); Carter, James (Inventor); Schattenburg, Mark (Inventor)

    1998-01-01

    X-ray masking apparatus includes a frame having a supporting rim surrounding an x-ray transparent region, a thin membrane of hard inorganic x-ray transparent material attached at its periphery to the supporting rim covering the x-ray transparent region and a layer of x-ray opaque material on the thin membrane inside the x-ray transparent region arranged in a pattern to selectively transmit x-ray energy entering the x-ray transparent region through the membrane to a predetermined image plane separated from the layer by the thin membrane. A method of making the masking apparatus includes depositing back and front layers of hard inorganic x-ray transparent material on front and back surfaces of a substrate, depositing back and front layers of reinforcing material on the back and front layers, respectively, of the hard inorganic x-ray transparent material, removing the material including at least a portion of the substrate and the back layers of an inside region adjacent to the front layer of hard inorganic x-ray transparent material, removing a portion of the front layer of reinforcing material opposite the inside region to expose the surface of the front layer of hard inorganic x-ray transparent material separated from the inside region by the latter front layer, and depositing a layer of x-ray opaque material on the surface of the latter front layer adjacent to the inside region.

  19. Experimental X-Ray Ghost Imaging

    NASA Astrophysics Data System (ADS)

    Pelliccia, Daniele; Rack, Alexander; Scheel, Mario; Cantelli, Valentina; Paganin, David M.

    2016-09-01

    We report an experimental proof of principle for ghost imaging in the hard-x-ray energy range. We use a synchrotron x-ray beam that is split using a thin crystal in Laue diffraction geometry. With an ultrafast imaging camera, we are able to image x rays generated by isolated electron bunches. At this time scale, the shot noise of the synchrotron emission process is measurable as speckles, leading to speckle correlation between the two beams. The integrated transmitted intensity from a sample located in the first beam is correlated with the spatially resolved intensity measured in the second, empty, beam to retrieve the shadow of the sample. The demonstration of ghost imaging with hard x rays may open the way to protocols to reduce radiation damage in medical imaging and in nondestructive structural characterization using free electron lasers.

  20. Laboratory Data for X-Ray Astronomy

    NASA Technical Reports Server (NTRS)

    Beiersdorfer, P.; Brown, G. V.; Chen, H.; Gu, M.-F.; Kahn, S. M.; Lepson, J. K.; Savin, D. W.; Utter, S. B.

    2000-01-01

    Laboratory facilities have made great strides in producing large sets of reliable data for X-ray astronomy, which include ionization and recombination cross sections needed for charge balance calculations as well as the atomic data needed for interpreting X-ray line formation. We discuss data from the new generation sources and pay special attention to the LLNL electron beam ion trap experiment, which is unique in its ability to provide direct laboratory access to spectral data under precisely controlled conditions that simulate those found in many astrophysical plasmas. Examples of spectral data obtained in the 1-160 A wavelength range are given illustrating the type of laboratory X-ray data produced in support of such missions as Chandra, X-Ray Multi-Mirror telescope (XMM), Advanced Satellite for Cosmology and Astrophysics (ASCA) and Extreme Ultraviolet Explorer Satellite (EUVE).

  1. Dental x-ray diagnostic installation

    SciTech Connect

    Grassme, U.

    1985-02-19

    An exemplary embodiment comprises an exposure unit including an X-ray tube and a cassette holder rotatable about vertical axes and between which the head of the patient is disposed. A radiation detector is disposed at the cassette holder for supplying an electrical signal corresponding to the dose rate when it is struck by X-rays and being interconnected with an X-ray tube voltage controller and a dose rate regulator in such manner that the X-ray tube voltage is influenced by the output of the radiation detector to control the dose rate to a value producing an optimum film blackening. A function generator determining the speed of the exposure unit is provided in which a speed curve is stored given which the radiation dose influencing the film is approximately constant.

  2. High Resolution X-Ray Phase Contrast Imaging with Acoustic Tissue-Selective Contrast Enhancement

    DTIC Science & Technology

    2005-06-01

    microfocus x - ray source. Rev. Sci. Instr. 68, 2774 (1997). 8. Krol, A. et al. Laser-based microfocused x - ray ...high spatial coherence, such as synchrotrons 46, microfocus x - ray tubes 7, or laser plasma x - ray sources 8,9are employed is the phase contrast component...imaging apparatus to determine the deflection of the bead as a function of acoustic pressure. The x - rays , generated by a microfocus x - ray tube

  3. Generation of circularly polarized radiation from a compact plasma-based extreme ultraviolet light source for tabletop X-ray magnetic circular dichroism studies

    SciTech Connect

    Wilson, Daniel; Rudolf, Denis Juschkin, Larissa; Weier, Christian; Adam, Roman; Schneider, Claus M.; Winkler, Gerrit; Frömter, Robert; Danylyuk, Serhiy; Bergmann, Klaus; Grützmacher, Detlev

    2014-10-15

    Generation of circularly polarized light in the extreme ultraviolet (EUV) spectral region (about 25 eV–250 eV) is highly desirable for applications in spectroscopy and microscopy but very challenging to achieve in a small-scale laboratory. We present a compact apparatus for generation of linearly and circularly polarized EUV radiation from a gas-discharge plasma light source between 50 eV and 70 eV photon energy. In this spectral range, the 3p absorption edges of Fe (54 eV), Co (60 eV), and Ni (67 eV) offer a high magnetic contrast often employed for magneto-optical and electron spectroscopy as well as for magnetic imaging. We simulated and designed an instrument for generation of linearly and circularly polarized EUV radiation and performed polarimetric measurements of the degree of linear and circular polarization. Furthermore, we demonstrate first measurements of the X-ray magnetic circular dichroism at the Co 3p absorption edge with a plasma-based EUV light source. Our approach opens the door for laboratory-based, element-selective spectroscopy of magnetic materials and spectro-microscopy of ferromagnetic domains.

  4. X-ray laser driven gold targets

    SciTech Connect

    Petrova, Tz. B. Whitney, K. G.; Davis, J.

    2014-03-15

    The femtosecond population dynamics of gold irradiated by a coherent high-intensity (>10{sup 17} W/cm{sup 2}) x-ray laser pulse is investigated theoretically. There are two aspects to the assembled model. One is the construction of a detailed model of platinum-like gold inclusive of all inner-shell states that are created by photoionization of atomic gold and decay either by radiative or Auger processes. Second is the computation of the population dynamics that ensues when an x-ray pulse is absorbed in gold. The hole state generation depends on the intensity and wavelength of the driving x-ray pulse. The excited state populations reached during a few femtosecond timescales are high enough to generate population inversions, whose gain coefficients are calculated. These amplified lines in the emitted x-ray spectrum provide important diagnostics of the radiation dynamics and also suggest a nonlinear way to increase the frequency of the coherent output x-ray pulses relative to the frequency of the driver input x-ray pulse.

  5. Panoramic Dental X-Ray

    MedlinePlus

    ... Physician Resources Professions Site Index A-Z Panoramic Dental X-ray Panoramic dental x-ray uses a ... Your e-mail address: Personal message (optional): Bees: Wax: Notice: RadiologyInfo respects your privacy. Information entered here ...

  6. Fluctuation X-Ray Scattering

    SciTech Connect

    Saldin, PI: D. K.; Co-I's: J. C. H. Spence and P. Fromme

    2013-01-25

    The work supported by the grant was aimed at developing novel methods of finding the structures of biomolecules using x-rays from novel sources such as the x-ray free electron laser and modern synchrotrons

  7. Abdomen X-Ray (Radiography)

    MedlinePlus

    ... examined, an x-ray machine produces a small burst of radiation that passes through the body, recording ... tissue shows up in shades of gray and air appears black. Until recently, x-ray images were ...

  8. Dual X-ray absorptiometry

    NASA Astrophysics Data System (ADS)

    Altman, Albert; Aaron, Ronald

    2012-07-01

    Dual X-ray absorptiometry is widely used in analyzing body composition and imaging. Both the method and its limitations are related to the Compton and photoelectric contributions to the X-ray attenuation coefficients of materials.

  9. Encapsulating X-Ray Detectors

    NASA Technical Reports Server (NTRS)

    Conley, Joseph M.; Bradley, James G.

    1987-01-01

    Vapor-deposited polymer shields crystals from environment while allowing X rays to pass. Polymer coating transparental to X rays applied to mercuric iodide detector in partial vacuum. Coating protects crystal from sublimation, chemical attack, and electrical degradation.

  10. Development of a lab-scale, high-resolution, tube-generated X-ray computed-tomography system for three-dimensional (3D) materials characterization

    SciTech Connect

    Mertens, J.C.E. Williams, J.J. Chawla, Nikhilesh

    2014-06-01

    The design and construction of a modular high resolution X-ray computed tomography (XCT) system is highlighted in this paper. The design approach is detailed for meeting a specified set of instrument performance goals tailored towards experimental versatility and high resolution imaging. The XCT tool is unique in the detector and X-ray source design configuration, enabling control in the balance between detection efficiency and spatial resolution. The system package is also unique: The sample manipulation approach implemented enables a wide gamut of in situ experimentation to analyze structure evolution under applied stimulus, by optimizing scan conditions through a high degree of controllability. The component selection and design process is detailed: Incorporated components are specified, custom designs are shared, and the approach for their integration into a fully functional XCT scanner is provided. Custom designs discussed include the dual-target X-ray source cradle which maintains position and trajectory of the beam between the two X-ray target configurations with respect to a scintillator mounting and positioning assembly and the imaging sensor, as well as a novel large-format X-ray detector with enhanced adaptability. The instrument is discussed from an operational point of view, including the details of data acquisition and processing implemented for 3D imaging via micro-CT. The performance of the instrument is demonstrated on a silica-glass particle/hydroxyl-terminated-polybutadiene (HTPB) matrix binder PBX simulant. Post-scan data processing, specifically segmentation of the sample's relevant microstructure from the 3D reconstruction, is provided to demonstrate the utility of the instrument. - Highlights: • Custom built X-ray tomography system for microstructural characterization • Detector design for maximizing polychromatic X-ray detection efficiency • X-ray design offered for maximizing X-ray flux with respect to imaging resolution • Novel lab

  11. SAS 3 survey of the soft X-ray background

    NASA Technical Reports Server (NTRS)

    Marshall, F. J.; Clark, G. W.

    1984-01-01

    The results of a survey of the soft X-ray sky in the C band (0.10-0.28keV) are reported. The observations were carried out using two independent flow proportional counters on board the SAS 3 X-ray satellite which had a total angular resolution of 2.9 deg FWHM, and a total exposure of 2.2 x 10 to the 4th per sq cm s sr. It is found that C band counting rates were generally inversely correlated with the column density of the neutral hydrogen on all angular scales down to the lowest angular resolution of the detectors. In the region 90-180 deg l and 0-10 deg b, the relation between C-band rates and the column densities of neutral hydrogen was fitted with a residual rms deviation of less than 13 percent by a two-component numerical model of the X-ray background. For the apparent attenuation column density a value of 2.7 x 10 to the 20th per sq cm was obtained. On the basis of a computer simulation of the SAS 3 data, it is shown that the observed clumping of interstellar matter was consistent with the magnitude of spatial fluctuations in the C-band map. When the background rates were subtracted from the survey map, the subsequent map showed foreground emission and absorption features with improved sensitivity and clarity. A series of computer-generated maps incorporating the SAS 3 data is given in an appendix.

  12. Apparatus for monitoring X-ray beam alignment

    DOEpatents

    Steinmeyer, P.A.

    1991-10-08

    A self-contained, hand-held apparatus is provided for monitoring alignment of an X-ray beam in an instrument employing an X-ray source. The apparatus includes a transducer assembly containing a photoresistor for providing a range of electrical signals responsive to a range of X-ray beam intensities from the X-ray beam being aligned. A circuit, powered by a 7.5 VDC power supply and containing an audio frequency pulse generator whose frequency varies with the resistance of the photoresistor, is provided for generating a range of audible sounds. A portion of the audible range corresponds to low X-ray beam intensity. Another portion of the audible range corresponds to high X-ray beam intensity. The transducer assembly may include an a photoresistor, a thin layer of X-ray fluorescent material, and a filter layer transparent to X-rays but opaque to visible light. X-rays from the beam undergoing alignment penetrate the filter layer and excite the layer of fluorescent material. The light emitted from the fluorescent material alters the resistance of the photoresistor which is in the electrical circuit including the audio pulse generator and a speaker. In employing the apparatus, the X-ray beam is aligned to a complete alignment by adjusting the X-ray beam to produce an audible sound of the maximum frequency. 2 figures.

  13. Apparatus for monitoring X-ray beam alignment

    DOEpatents

    Steinmeyer, Peter A.

    1991-10-08

    A self-contained, hand-held apparatus is provided for minitoring alignment of an X-ray beam in an instrument employing an X-ray source. The apparatus includes a transducer assembly containing a photoresistor for providing a range of electrical signals responsive to a range of X-ray beam intensities from the X-ray beam being aligned. A circuit, powered by a 7.5 VDC power supply and containing an audio frequency pulse generator whose frequency varies with the resistance of the photoresistor, is provided for generating a range of audible sounds. A portion of the audible range corresponds to low X-ray beam intensity. Another portion of the audible range corresponds to high X-ray beam intensity. The transducer assembly may include an a photoresistor, a thin layer of X-ray fluorescent material, and a filter layer transparent to X-rays but opaque to visible light. X-rays from the beam undergoing alignment penetrate the filter layer and excite the layer of fluorescent material. The light emitted from the fluorescent material alters the resistance of the photoresistor which is in the electrical circuit including the audio pulse generator and a speaker. In employing the apparatus, the X-ray beam is aligned to a complete alignment by adjusting the X-ray beam to produce an audible sound of the maximum frequency.

  14. Proceedings of the workshop on X-ray computed microtomography

    SciTech Connect

    1998-02-01

    This report consists of vugraphs from the nine presentations at the conference. Titles of the presentations are: CMT: Applications and Techniques; Computer Microtomography Using X-rays from Third Generation Synchrotron X-ray; Approaches to Soft-X-ray Nanotomography; Diffraction Enhanced Tomography; X-ray Computed Microtomography Applications at the NSLS; XCMT Applications in Forestry and Forest Products; 3DMA: Investigating Three Dimensional Pore Geometry from High Resolution Images; X-ray Computed Microtomography Studies of Volcanic Rock; and 3-D Visualization of Tomographic Volumes.

  15. X-Ray Exam: Hip

    MedlinePlus

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  16. X-Ray Exam: Wrist

    MedlinePlus

    ... Old Feeding Your 1- to 2-Year-Old X-Ray Exam: Wrist KidsHealth > For Parents > X-Ray Exam: Wrist A A A What's in this ... español Radiografía: muñeca What It Is A wrist X-ray is a safe and painless test that uses ...

  17. X-Ray Exam: Ankle

    MedlinePlus

    ... Old Feeding Your 1- to 2-Year-Old X-Ray Exam: Ankle KidsHealth > For Parents > X-Ray Exam: Ankle A A A What's in this ... español Radiografía: tobillo What It Is An ankle X-ray is a safe and painless test that uses ...

  18. X-Ray Exam: Foot

    MedlinePlus

    ... Old Feeding Your 1- to 2-Year-Old X-Ray Exam: Foot KidsHealth > For Parents > X-Ray Exam: Foot A A A What's in this ... español Radiografía: pie What It Is A foot X-ray is a safe and painless test that uses ...

  19. X-Ray Exam: Finger

    MedlinePlus

    ... Old Feeding Your 1- to 2-Year-Old X-Ray Exam: Finger KidsHealth > For Parents > X-Ray Exam: Finger Print A A A What's in ... español Radiografía: dedo What It Is A finger X-ray is a safe and painless test that uses ...

  20. X-Ray Exam: Foot

    MedlinePlus

    ... Old Feeding Your 1- to 2-Year-Old X-Ray Exam: Foot KidsHealth > For Parents > X-Ray Exam: Foot Print A A A What's in ... español Radiografía: pie What It Is A foot X-ray is a safe and painless test that uses ...

  1. X-Ray Exam: Ankle

    MedlinePlus

    ... Old Feeding Your 1- to 2-Year-Old X-Ray Exam: Ankle KidsHealth > For Parents > X-Ray Exam: Ankle Print A A A What's in ... español Radiografía: tobillo What It Is An ankle X-ray is a safe and painless test that uses ...

  2. X-Ray Exam: Pelvis

    MedlinePlus

    ... Old Feeding Your 1- to 2-Year-Old X-Ray Exam: Pelvis KidsHealth > For Parents > X-Ray Exam: Pelvis Print A A A What's in ... español Radiografía: pelvis What It Is A pelvis X-ray is a safe and painless test that uses ...

  3. Electron beam injected into ground generates subsoil x-rays that may deactivate concealed electronics used to trigger explosive devices

    NASA Astrophysics Data System (ADS)

    Retsky, Michael

    2008-04-01

    Explosively formed projectiles (EFP) are a major problem in terrorism and asymmetrical warfare. EFPs are often triggered by ordinary infrared motion detectors. A potential weak link is that such electronics are not hardened to ionizing radiation and can latch-up or enter other inoperative states after exposure to a single short event of ionizing radiation. While these can often be repaired with a power restart, they also can produce shorts and permanent damage. A problem of course is that we do not want to add radiation exposure to the long list of war related hazards. Biological systems are highly sensitive to integrated dosage but show no particular sensitivity to short pulses. There may be a way to generate short pulsed subsoil radiation to deactivate concealed electronics without introducing radiation hazards to military personnel and civilian bystanders. Electron beams of 30 MeV that can be produced by portable linear accelerators (linacs) propagate >20 m in air and 10-12 cm in soil. X-radiation is produced by bremsstrahlung and occurs subsoil beneath the point of impact and is mostly forward directed. Linacs 1.5 m long can produce 66 MWatt pulses of subsoil x-radiation 1 microsecond or less in duration. Untested as yet, such a device could be mounted on a robotic vehicle that precedes a military convoy and deactivates any concealed electronics within 10-20 meters on either side of the road.

  4. Self-consistent simulation of an electron beam for a new autoresonant x-ray generator based on TE 102 rectangular mode

    NASA Astrophysics Data System (ADS)

    Dugar-Zhabon, V. D.; Orozco, E. A.; Herrera, A. M.

    2016-02-01

    The space cyclotron autoresonance interaction of an electron beam with microwaves of TE 102 rectangular mode is simulated. It is shown that in these conditions the beam electrons can achieve energies which are sufficient to generate hard x-rays. The physical model consists of a rectangular cavity fed by a magnetron oscillator through a waveguide with a ferrite isolator, an iris window and a system of dc current coils which generates an axially symmetric magnetic field. The 3D magnetic field profile is that which maintains the electron beam in the space autoresonance regime. To simulate the beam dynamics, a full self-consistent electromagnetic particle-in-cell code is developed. It is shown that the injected 12keV electron beam of 0.5A current is accelerated to energy of 225keV at a distance of an order of 17cm by 2.45GHz standing microwave field with amplitude of 14kV/cm.

  5. POPULATION KINETICS MODELING FOR NON-LTE AND NON-MAXWELLIAN PLASMAS GENERATED IN FINITE TEMPERATURE DENSE MATTER EXPERIMENTS ARISING FROM SHORT PULSE X-RAY SOURCE

    SciTech Connect

    Chung, H; Lee, R W; Morgan, W L

    2003-12-23

    The short pulse x-ray sources will provide a major advance in dense matter studies important to understand implosion physics for ICF as a generator of warm dense matter or a probe of finite temperature dense matter. The interaction of such a high-energy photon pulse with the initially solid matter creates highly transient states of plasmas initially whose relaxation processes are of interest to the equation of states or spectral properties of these matter. For these plasmas, assumptions such as LTE population distributions or Maxwellian electron energy distributions should be tested by employing a method that does not make these assumption a priori. Our goal is to present a model that can be used to simulate the electron distributions, the ionization balance and the spectral output of transient systems generated in the future ICF experiments. We report on the progress in developing a non-LTE atomic population kinetics code integrated with Boltzmann equation solver to provide a self-consistent time-dependent solution of the level populations and the particle energy distributions.

  6. Structural factors affecting pore space transformation during hydrocarbon generation in source rock (shales): laboratory experiments and X-ray microtomography/SEM study

    NASA Astrophysics Data System (ADS)

    Giliazetdinova, Dina; Korost, Dmitry; Gerke, Kirill

    2015-04-01

    Oil and gas generation is a complex superposition of processes which take place in the interiors and are not readily observable in nature in human life time-frames. During burial of the source rocks organic matter is transformed into a mixture of high-molecular compounds - precursors of oil and gas (kerogen). Specific thermobaric conditions trigger formation of low molecular weight hydrocarbon compounds. Generation of sufficient quantities of hydrocarbons leads to the primary fluid migration. For series of our experiments we selected mainly siliceous-carbonate composition shale rocks from Domanic horizon of South-Tatar arch. Rock samples were heated in the pyrolyzer to temperatures closely corresponding to different catagenesis stages. X-ray microtomography method was used to monitor changes in the morphology of the pore space within studied shale rocks. By routine measurements we made sure that all samples (10 in total) had similar composition of organic and mineral phases. All samples in the collection were grouped according to initial structure and amount of organics and processed separately to: 1) study the influence of organic matter content on the changing morphology of the rock under thermal effects; 2) study the effect of initial structure on the primary migration processes for samples with similar organic matter content. An additional experiment was conducted to study the dynamics of changes in the structure of the pore space and prove the validity of our approach. At each stage of heating the morphology of altered rocks was characterized by formation of new pores and channels connecting primary voids. However, it was noted that the samples with a relatively low content of the organic matter had less changes in pore space morphology, in contrast to rocks with a high organic content. Second part of the study also revealed significant differences in resulting pore structures depending on initial structure of the unaltered rocks and connectivity of original

  7. X-ray satellite

    NASA Technical Reports Server (NTRS)

    1985-01-01

    An overview of the second quarter 1985 development of the X-ray satellite project is presented. It is shown that the project is proceeding according to plan and that the projected launch date of September 9, 1987 is on schedule. An overview of the work completed and underway on the systems, subsystems, payload, assembly, ground equipment and interfaces is presented. Problem areas shown include cost increases in the area of focal instrumentation, the star sensor light scattering requirements, and postponements in the data transmission subsystems.

  8. SMM x ray polychromator

    NASA Technical Reports Server (NTRS)

    Saba, J. L. R.

    1993-01-01

    The objective of the X-ray Polychromator (XRP) experiment was to study the physical properties of solar flare plasma and its relation to the parent active region to understand better the flare mechanism and related solar activity. Observations were made to determine the temperature, density, and dynamic structure of the pre-flare and flare plasma as a function of wavelength, space and time, the extent to which the flare plasma departs from thermal equilibrium, and the variation of this departure with time. The experiment also determines the temperature and density structure of active regions and flare-induced changes in the regions.

  9. X-ray absorption fine structure measurement with a 9 V electric battery x-ray emitter

    SciTech Connect

    Mitsuya, Shota; Ishii, Hideshi; Kawai, Jun; Tanaka, Keiichi

    2006-09-25

    X-ray absorption spectral analysis is a well known technique for analyzing the chemical environment of an element in a specimen. It has been believed that high intensity and monochromatized x rays such as the synchrotron radiation are required for an x-ray absorption experiment. In the present study, however, we demonstrate that the x-ray absorption spectral measurement of transition metal foils with an energy resolution of 10 eV is possible with a combination of a 9 V dry electric battery pyroelectric x-ray generator and a superconducting microcalorimeter.

  10. X-ray scattering from dense plasmas

    NASA Astrophysics Data System (ADS)

    McSherry, Declan Joseph

    Dense plasmas were studied by probing them with kilovolt x-rays and measuring those scattered at various angles. The laser produced x-ray source emitted Ti He alpha 4.75 keV x-rays. Two different plasma types were explored. The first was created by laser driven shocks on either side of a sample foil consisting of 2 micron thickness of Al, sandwiched between two 1 micron CH layers. We have observed a peak in the x-ray scattering cross section, indicating diffraction from the plasma. However, the experimentally inferred plasma density, did not always agree broadly with the hydrodynamic simulation MEDX (A modified version of MEDUSA). The second plasma type that we studied was created by soft x-ray heating on either side of a sample foil, this time consisting of 1 micron thickness of Al, sandwiched between two 0.2 micron CH layers. Two foil targets, each consisting of a 0.1 micron thick Au foil mounted on 1 micron of CH, were placed 4 mm from the sample foil. The soft x-rays were produced by laser irradiating these two foil targets. We found that, 0.5 ns after the peak of the laser heating pulses, that the measured cross sections more closely matched those simulated using the Thomas Fermi model than the Inferno model. Later in time, at 2 ns, the plasma is approaching a weakly coupled state. This is the first time x-ray scattering cross sections have been measured from dense plasmas generated by radiatively heating both sides of the sample. Moreover, these are absolute values typically within a factor of two of expectation for early x-ray probe times.

  11. Compton backscattered collimated x-ray source

    DOEpatents

    Ruth, Ronald D.; Huang, Zhirong

    1998-01-01

    A high-intensity, inexpensive and collimated x-ray source for applications such as x-ray lithography is disclosed. An intense pulse from a high power laser, stored in a high-finesse resonator, repetitively collides nearly head-on with and Compton backscatters off a bunched electron beam, having relatively low energy and circulating in a compact storage ring. Both the laser and the electron beams are tightly focused and matched at the interaction region inside the optical resonator. The laser-electron interaction not only gives rise to x-rays at the desired wavelength, but also cools and stabilizes the electrons against intrabeam scattering and Coulomb repulsion with each other in the storage ring. This cooling provides a compact, intense bunch of electrons suitable for many applications. In particular, a sufficient amount of x-rays can be generated by this device to make it an excellent and flexible Compton backscattered x-ray (CBX) source for high throughput x-ray lithography and many other applications.

  12. Compton backscattered collmated X-ray source

    DOEpatents

    Ruth, Ronald D.; Huang, Zhirong

    2000-01-01

    A high-intensity, inexpensive and collimated x-ray source for applications such as x-ray lithography is disclosed. An intense pulse from a high power laser, stored in a high-finesse resonator, repetitively collides nearly head-on with and Compton backscatters off a bunched electron beam, having relatively low energy and circulating in a compact storage ring. Both the laser and the electron beams are tightly focused and matched at the interaction region inside the optical resonator. The laser-electron interaction not only gives rise to x-rays at the desired wavelength, but also cools and stabilizes the electrons against intrabeam scattering and Coulomb repulsion with each other in the storage ring. This cooling provides a compact, intense bunch of electrons suitable for many applications. In particular, a sufficient amount of x-rays can be generated by this device to make it an excellent and flexible Compton backscattered x-ray (CBX) source for high throughput x-ray lithography and many other applications.

  13. Compton backscattered collimated x-ray source

    DOEpatents

    Ruth, R.D.; Huang, Z.

    1998-10-20

    A high-intensity, inexpensive and collimated x-ray source is disclosed for applications such as x-ray lithography is disclosed. An intense pulse from a high power laser, stored in a high-finesse resonator, repetitively collides nearly head-on with and Compton backscatters off a bunched electron beam, having relatively low energy and circulating in a compact storage ring. Both the laser and the electron beams are tightly focused and matched at the interaction region inside the optical resonator. The laser-electron interaction not only gives rise to x-rays at the desired wavelength, but also cools and stabilizes the electrons against intrabeam scattering and Coulomb repulsion with each other in the storage ring. This cooling provides a compact, intense bunch of electrons suitable for many applications. In particular, a sufficient amount of x-rays can be generated by this device to make it an excellent and flexible Compton backscattered x-ray (CBX) source for high throughput x-ray lithography and many other applications. 4 figs.

  14. The X-ray imager on AXO

    NASA Astrophysics Data System (ADS)

    Budtz-Jørgensen, C.; Kuvvetli, I.; Westergaard, N. J.; Jonasson, P.; Reglero, V.; Eyles, C.

    2001-02-01

    DSRI has initiated a development program of CZT X-ray and gamma-ray detectors employing strip readout techniques. A dramatic improvement of the energy response was found operating the detectors as the so-called drift detectors. For the electronic readout, modern ASIC chips were investigated. Modular design and the low-power electronics will make large area detectors using the drift strip method feasible. The performance of a prototype CZT system will be presented and discussed. One such detector system has been proposed for future space missions: the X-Ray Imager (XRI) on the Atmospheric X-ray Observatory (AXO), which is a mission proposed to the Danish Small Satellite Program and is dedicated to observations of X-ray generating processes in the Earth's atmosphere. Of special interest will be simultaneous optical and X-ray observations of sprites that are flashes appearing directly above an active thunderstorm system. Additional objective is a detailed mapping of the auroral X-ray and optical emission. XRI comprises a coded mask and a 20×40 cm 2 CZT detector array covering an energy range from 5 to 200 keV.

  15. Is low-energy-ion bombardment generated X-ray emission a secondary mutational source to ion-beam-induced genetic mutation?

    NASA Astrophysics Data System (ADS)

    Thongkumkoon, P.; Prakrajang, K.; Thopan, P.; Yaopromsiri, C.; Suwannakachorn, D.; Yu, L. D.

    2013-07-01

    Low-energy ion beam biotechnology has achieved tremendous successes in inducing crop mutation and gene transfer. However, mechanisms involved in the related processes are not yet well understood. In ion-beam-induced mutation, ion-bombardment-produced X-ray has been proposed to be one of the secondary mutation sources, but the speculation has not yet been experimentally tested. We carried out this investigation to test whether the low-energy ion-beam-produced X-ray was a source of ion-beam-induced mutation. In the investigation, X-ray emission from 29-keV nitrogen- or argon- ion beam bombarded bacterial Escherichia coli (E. coli) cells held in a metal or plastic sample holder was in situ detected using a highly sensitive X-ray detector. The ion beam bombarded bacterial cells held in different material holders were observed for mutation induction. The results led to a conclusion that secondary X-ray emitted from ion-beam-bombarded biological living materials themselves was not a, or at least a negligible, mutational source, but the ion-beam-induced X-ray emission from the metal that made the sample holder could be a source of mutation.

  16. X-ray lithography source

    DOEpatents

    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.

  17. X-ray lithography source

    DOEpatents

    Piestrup, M.A.; Boyers, D.G.; Pincus, C.

    1991-12-31

    A high-intensity, inexpensive X-ray source for X-ray lithography for the production of integrated circuits is disclosed. 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 eliminating 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 excellent moderate-priced X-ray source for lithography. 26 figures.

  18. High-intensity attosecond X-ray source generation by using low-intensity spatial inhomogeneous mid-infrared pulse combined with an ultraviolet pulse

    NASA Astrophysics Data System (ADS)

    Feng, Liqiang; Liu, Hang

    2017-01-01

    We theoretically investigate the high-order harmonic spectra and the attosecond pulse generation from He+ ion driven by the spatial inhomogeneous combined field, consisting of a two-color low-intensity mid-infrared pulse (1013 W/cm2) and an ultraviolet (UV) pulse (1012 W/cm2). The numerical results show that due to the spatial inhomogeneous effect, the harmonic cutoffs are remarkably extended, and a 986 eV super-continuum can be obtained. Further with the proper introduction of an UV pulse (from 60 nm to 20 nm) to the two-color field, the harmonic yields are enhanced, especially for adding the 30 nm pulse case, a 1113 eV super-continuum (corresponding to a 34.1 dB enhanced field) with less harmonic modulation and six orders of magnitude enhancement can be obtained. Similar calculations have been performed for He atom and an 896 eV super-continuum with four orders of magnitude enhancement can be produced. Time-frequency harmonic distribution and time-dependent electron populations show that the single short quantum path contribution is responsible for the less harmonic modulation and the laser-induced electron excitation is responsible for the harmonic enhancement. Finally, by properly superposing the harmonics, a series of sub-50-as pulses including the whole X-ray region with 3-6 orders of magnitude enhancement can be obtained.

  19. X-Ray Generated Ultrasound.

    DTIC Science & Technology

    1986-01-30

    1986 Navy Regional Finance Center 13. NUMBER OF PAGES CM 3, Room 206, Attn: Code 40, Wash.D.C.20371-540 62 14. MONITORING AGENCY NAME & ADDRESS(If...I Availability Codes Avail arndlor Dist Special 1.0 DESCRIPTION OF THE PROBLEM 4A-. The focus of this research program is an investigation of the...high source repetition rate, the detailed signal deconvolution procedure originally proposed could no longer be implemented. Experiments were designed

  20. Second-generation surveillance for HIV/AIDS in Pakistan: results from the 4th round of Integrated Behavior and Biological Survey 2011–2012

    PubMed Central

    Emmanuel, Faran; Salim, Momina; Akhtar, Naeem; Arshad, Salwa; Reza, Tahira Ezra

    2013-01-01

    Objectives In an effort to fully analyse and understand the HIV situation and its epidemiology in Pakistan, a bilateral collaboration between the National AIDS Control Program and the Canadian International Development Agency resulted in the establishment of an effective second-generation surveillance (SGS) system for HIV/AIDS between 2004 and 2012 in accordance with the published guidelines. This paper presents findings from the 4th round of SGS. Methods A mapping exercise was initially conducted for size estimations of the key vulnerable populations: people who inject drugs (PWIDs), male sex workers (MSWs), hijra sex workers (HSWs), and female sex workers (FSWs), followed by an Integrated Behavioral and Biological Surveillance in 20 selected cities across Pakistan. Results The estimated sizes of the four key populations mapped in the 20 cities were 89 178 FSWs, 46 351 PWIDs, 23 317 HSWs and 19 119 MSWs. The HIV sero-prevalence among PWIDs was the highest among all key populations surveyed at 37.8% (CI 37.3 to 38.3) nationally, followed by a prevalence of 7.2% (CI 6.8 to 7.5) among HSWs, 3.1% (CI 2.8 to 3.4) among MSWs and 0.8% (CI 0.4 to 1.0) for FSWs. Various key risk behaviours, that is, sharing of syringes by PWIDs and inconsistent use of condoms by sex workers, were documented. Conclusions Pakistan's HIV epidemic that once was characterised primarily by transmission among PWIDs is now increasingly characterised by significant sexual transmission, and all types of sex workers (male, hijra and female) exhibit epidemiological proportions of infection. There is a need to develop concrete strategic plans for each vulnerable subpopulation, initially focusing prevention resources on those with a higher risk or vulnerability. PMID:23912818

  1. Pore-space alteration in source rock (shales) during hydrocarbons generation: X-ray microtomography and pore-scale modelling study

    NASA Astrophysics Data System (ADS)

    Korost, Dmitry; Gerke, Kirill; Akhmanov, Grigory; Vasilyev, Roman; Čapek, Pavel; Karsanina, Marina; Nadezhkin, Dmitry

    2013-04-01

    Hydrocarbons (HC) are generated from solid organic matter (kerogen) due to thermocatalytic reactions. The rate of such reactions shows direct correlation with temperature and depends on the depth of source rock burial. Burial of sedimentary rock is also inevitably accompanied by its structural alteration owing to compaction, dehydration and re-crystallization. Processes of HC generation, primary migration and structural changes are inaccessible for direct observation in nature, but they can be studied in laboratory experiments. Modern technical facilities of laboratories make it possible to carry out experiments on HC generation from the organic-rich rocks at a completely new level (Kobchenko et al., 2011). Some new technologies, including X-ray microtomography and pore-scale modeling, allow us to carry out a step-by-step description of such processes and their development, and to study their reflection in alterations of rock structure. Experiments were carried out with a clayey-carbonate rock sample of the Domanic Formaition taken at a depth of 1939 m from borehole drilled in the central part of the Melekes depression (West Tatar arch, Russia). The rock chosen fits the very essential requirements for studying HC generation under laboratory conditions - high organic matter content and its low metamorphic grade. Our work aimed such a study in an undisturbed rock sample by heating it in nitrogen atmosphere based on a specified temperature regime in a RockEval6 analyzer and monitoring alterations in the pore space structure. Observations were carried out with a SkyScan-1172 X-ray microtomography scanner (resulting scan resolution of 1 µm). A cylinder, 4 mm in diameter, was prepared from the rock sample for the pyrolitic and microtomographic analyses. Scanning procedures were carried out in 5 runs. Temperature interval for each run had to match the most important stage of HC generation in the source rock, namely: (1) original structure; (2) 100-300

  2. Hard x-ray nanoprobe based on refractive x-ray lenses

    SciTech Connect

    Schroer, C.G.; Kurapova, O.; Patommel, J.; Boye, P.; Feldkamp, J.; Lengeler, B.; Burghammer, M.; Riekel, C.; Vincze, L.; Hart, A. van der; Kuechler, M.

    2005-09-19

    Based on nanofocusing refractive x-ray lenses a hard x-ray scanning microscope is currently being developed and is being implemented at beamline ID13 of the European Synchrotron Radiation Facility (Grenoble, France). It can be operated in transmission, fluorescence, and diffraction mode. Tomographic scanning allows one to determine the inner structure of a specimen. In this device, a monochromatic (E=21 keV) hard x-ray nanobeam with a lateral extension of 47x55 nm{sup 2} was generated. Further reduction of the beam size to below 20 nm is targeted.

  3. Characterization of low intensity X-ray imaging devices (Lixiscope)

    NASA Technical Reports Server (NTRS)

    Ferguson, G. A.

    1981-01-01

    Radioisotopic sources were used to excite the LIXISCOPE in preliminary experimental attempts to evaluate the usefulness of this instrument for industrial and medical applications. The characteristics of the LIXISCOPE when excited by x-ray produced by conventional electrically powered x-ray generators were studied. The optimum x-ray spectrum was determined and the mode of operation of the generator, which yields satisfactory LIXISCOPE images of medical and industrial specimens was investigated.

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

    NASA Technical Reports Server (NTRS)

    Kaaret, P.

    1999-01-01

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

  5. Water-window flash x-ray production from linear plasma x-ray source

    NASA Astrophysics Data System (ADS)

    Sato, Eiichi; Sagae, Michiaki; Toriyabe, Hiroyuki; Awaji, Wataru; Hayasi, Yasuomi; Takayama, Kazuyoshi; Ido, Hideaki; Tamakawa, Yoshiharu

    2000-12-01

    The fundamental study on a high-intensity flash water-window x-ray generator is describe. This flash x-ray generator was improved in order to increase the x-ray intensity and to produce high-intensity characteristic x-rays by forming the linear plasma x-ray source. The generator consists of a high-voltage power supply, a polarity-inversion ignitron pulse generator, an oil-diffusion pump, and a radiation tube with a capillary. High-voltage condenser of 0.2 (mu) F in the pulse generator is charged up to 20 kV by the power supply, and the electric charges in the condenser are discharged to the capillary in the tube after closing the ignitron. In the present work, the chamber is evacuated by the pump with a pressure of about 1 mPa, and the titanium anode and cathode electrodes are employed to produce L-series characteristic x-rays in the water-window range. The diameter and the length of the ferrite capillary are 2.0 and 30 mm, respectively, and both the cathode voltage and the discharge current displayed damped oscillations. The peak values of the voltage and current increased when the charging voltage was increased, and their maximum values were -11.2 kV and 4.4 kA, respectively. The pulse durations of the water- windows x-rays were nearly equivalent to those of the damped oscillations in the voltage and current, and their values were less than 15 microsecond(s) . In the spectrum measurement, we observed water-window x-rays.

  6. X-ray Surveyor Discussion Session Results from the X-ray Vision Workshop

    NASA Astrophysics Data System (ADS)

    Allured, Ryan; Arenberg, Jonathan; Bogdan, Akos; Canning, Rebecca; Churazov, Eugene; Civano, Francesca; Clarke, Tracy; Corrales, Lia; Di Matteo, Tiziana; Elvis, Martin; Fabbiano, Giuseppina; Falcone, Abe; Garcia, Javier; Gaskin, Jessica; Goldman, Itzhak; Kargaltsev, Oleg; Klinger, Noel; Laming, Martin; McNamara, Brian; Markevitch, Maxim; Marshall, Herman; Mosquera, Ana; Mroczkowski, Anthony; Natarajan, Priyamvada; Nielsen, Joey; Nowak, Michael; Ozel, Feryal; Poppenhaeger, Katja; Porquet, Delphine; Randall, Scott; Schwartz, Daniel; Swartz, Douglas A.; Temim, Tea; Van Weeren, Reinout; Weisskopf, Martin; Zhuravleva, Irina; ZuHone, John A.

    2015-10-01

    This paper summarizes the results of a brainstorming session held during the X-ray Vision Workshop (Oct 6-8, 2015, Washington DC). The workshop was convened to discuss the scientific potential of the X-ray Surveyor mission. The X-ray Surveyor concept, which was defined by the Astrophysics Roadmap, is to effect a 100-fold gain in survey and spectroscopic capability over the Chandra X-ray Observatory, while at least matching Chandra’s sub-arcsecond imaging capability. This paper is intended to inform interested scientists of the growing discussion in our community and to solicit their input in the area of new science that a next generation high-resolution X-ray Observatory may provide for astrophysics. This paper is not an official document and is certainly not the definitive science case for an X-ray Surveyor mission. It is, instead, an early input to this discussion, which we hope will lead to a full reference white paper on the X-Ray Surveyor concept.

  7. Vacancy Generation and Oxygen Uptake in Cu-Doped Pr-CeO2 Materials using Neutron and in Situ X-ray Diffraction.

    PubMed

    D'Angelo, Anita M; Webster, Nathan A S; Chaffee, Alan L

    2016-12-19

    The oxygen uptake ability of Pr-CeO2-based oxygen carriers, catalysts, and solid oxide fuel cells can be attributed to 3+ cation generation and the presence of vacant oxygen sites. Oxygen occupancies of CeO2, Pr-CeO2, and 5% Cu-doped Pr-CeO2 were investigated using neutron diffraction and related to the oxygen uptake as determined using thermogravimetric analysis (TGA). The presence of vacant tetrahedral oxygen sites at room temperature did not correspond to low-temperature oxygen uptake. The materials did not uptake oxygen at 420 °C, but oxygen uptake was observed at 600 °C, which indicated that a minimum temperature needs to be met to generate sufficient vacancies/3+ cations. Variations in the lattice parameter as a function of temperature were revealed using in situ X-ray diffraction (XRD). With increasing temperature the lattice parameter increased linearly due to thermal expansion and was followed by an exponential increase at ∼300-400 °C as cations were reduced. Despite segregation of Cu into CuO at high dopant concentration, at 600 °C a higher O2 uptake was obtained for Ce0.65Pr0.20Cu0.15O2-δ (120 μmol g(-1)), in comparison to Ce0.75Pr0.2Cu0.05O2-δ (92 μmol g(-1)), and was higher than that for Ce0.8Pr0.2O2-δ (55 μmol g(-1)). Both Pr and Cu introduce vacancies and promote the O2 uptake of CeO2.

  8. 21 CFR 892.5930 - Therapeutic x-ray tube housing assembly.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Therapeutic x-ray tube housing assembly. 892.5930... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5930 Therapeutic x-ray tube housing assembly. (a) Identification. A therapeutic x-ray tube housing assembly is an x-ray generating tube...

  9. 21 CFR 892.1760 - Diagnostic x-ray tube housing assembly.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Diagnostic x-ray tube housing assembly. 892.1760... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1760 Diagnostic x-ray tube housing assembly. (a) Identification. A diagnostic x-ray tube housing assembly is an x-ray generating tube...

  10. 21 CFR 892.5930 - Therapeutic x-ray tube housing assembly.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Therapeutic x-ray tube housing assembly. 892.5930... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5930 Therapeutic x-ray tube housing assembly. (a) Identification. A therapeutic x-ray tube housing assembly is an x-ray generating tube...

  11. 21 CFR 892.5930 - Therapeutic x-ray tube housing assembly.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Therapeutic x-ray tube housing assembly. 892.5930... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5930 Therapeutic x-ray tube housing assembly. (a) Identification. A therapeutic x-ray tube housing assembly is an x-ray generating tube...

  12. 21 CFR 892.1760 - Diagnostic x-ray tube housing assembly.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Diagnostic x-ray tube housing assembly. 892.1760... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1760 Diagnostic x-ray tube housing assembly. (a) Identification. A diagnostic x-ray tube housing assembly is an x-ray generating tube...

  13. 21 CFR 892.5930 - Therapeutic x-ray tube housing assembly.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Therapeutic x-ray tube housing assembly. 892.5930... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5930 Therapeutic x-ray tube housing assembly. (a) Identification. A therapeutic x-ray tube housing assembly is an x-ray generating tube...

  14. 21 CFR 892.5930 - Therapeutic x-ray tube housing assembly.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Therapeutic x-ray tube housing assembly. 892.5930... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5930 Therapeutic x-ray tube housing assembly. (a) Identification. A therapeutic x-ray tube housing assembly is an x-ray generating tube...

  15. 21 CFR 892.1760 - Diagnostic x-ray tube housing assembly.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Diagnostic x-ray tube housing assembly. 892.1760... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1760 Diagnostic x-ray tube housing assembly. (a) Identification. A diagnostic x-ray tube housing assembly is an x-ray generating tube...

  16. 21 CFR 892.1760 - Diagnostic x-ray tube housing assembly.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Diagnostic x-ray tube housing assembly. 892.1760... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1760 Diagnostic x-ray tube housing assembly. (a) Identification. A diagnostic x-ray tube housing assembly is an x-ray generating tube...

  17. 21 CFR 892.1760 - Diagnostic x-ray tube housing assembly.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Diagnostic x-ray tube housing assembly. 892.1760... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1760 Diagnostic x-ray tube housing assembly. (a) Identification. A diagnostic x-ray tube housing assembly is an x-ray generating tube...

  18. Miniature x-ray source

    DOEpatents

    Trebes, James E.; Stone, Gary F.; Bell, Perry M.; Robinson, Ronald B.; Chornenky, Victor I.

    2002-01-01

    A miniature x-ray source capable of producing broad spectrum x-ray emission over a wide range of x-ray energies. The miniature x-ray source comprises a compact vacuum tube assembly containing a cathode, an anode, a high voltage feedthru for delivering high voltage to the anode, a getter for maintaining high vacuum, a connection for an initial vacuum pump down and crimp-off, and a high voltage connection for attaching a compact high voltage cable to the high voltage feedthru. At least a portion of the vacuum tube wall is highly x-ray transparent and made, for example, from boron nitride. The compact size and potential for remote operation allows the x-ray source, for example, to be placed adjacent to a material sample undergoing analysis or in proximity to the region to be treated for medical applications.

  19. British X-ray astronomy

    NASA Astrophysics Data System (ADS)

    Pounds, K. A.

    1986-09-01

    The development of solar and cosmic X-ray studies in the UK, in particular the Skylark and Ariel programs, is discussed. The characteristics and capabilities of the X-ray emulsion detector developed to monitor the solar X-radiation in the Skylark program, and of the proportional counter spectrometer developed for solar X-ray measurements on the Ariel I satellite are described. The designs and functions of the pin-hole camera, the Bragg crystal spectrometer, and the X-ray spectroheliograph are exmained. The Skylark observations of cosmic X-ray sources and high-resolution solar spectra, and the Ariel 5 data on cosmic X-ray sources are presented. Consideration is given to the Ariel 6, the U.S. Einstein Observatory, Exosat, and ASTRO-C.

  20. Solar X-ray physics

    SciTech Connect

    Bornmann, P.L. )

    1991-01-01

    Research on solar X-ray phenomena performed by American scientists during 1987-1990 is reviewed. Major topics discussed include solar images observed during quiescent times, the processes observed during solar flares, and the coronal, interplanetary, and terrestrial phenomena associated with solar X-ray flares. Particular attention is given to the hard X-ray emission observed at the start of the flare, the energy transfer to the soft X-ray emitting plasma, the late resolution of the flare as observed in soft X-ray, and the rate of occurrence of solar flares as a function of time and latitude. Pertinent aspects of nonflaring, coronal X-ray emission and stellar flares are also discussed. 175 refs.

  1. Topological X-Rays Revisited

    ERIC Educational Resources Information Center

    Lynch, Mark

    2012-01-01

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

  2. X-Ray Polarization Imaging

    DTIC Science & Technology

    2006-07-01

    anatomic structures. Johns and Yaffe (2), building on the work of Alvarez and Macovski (3) and that of Lehmann et al (4), discuss a method for...sources of contrast related to both the wave and par- ticulate nature of x rays. References 1. Johns PC, Yaffe MJ. X-ray characterization of normal and...application to mammography. Med Phys 1985; 12:289–296. 3. Alvarez RE, Macovski A. Energy-selective reconstructions in x-ray computerized tomography. Phys

  3. Development of an x-ray Talbot-Lau moire deflectometer for fast density profile measurements of dense plasmas generated by beam-target interactions

    SciTech Connect

    Clayton, Dan; Berninger, M; Meidinger, A; Stutman, Dan; Valdivia, Maria Pia

    2015-05-01

    For the first time an x-ray Talbot-Lau moire deflectometer is being developed that will use a flash tube source and fast detector for dynamic density gradient measurements. In Talbot-Lau moire deflectometry, an x-ray grating makes an image of itself on a second grating (the Talbot effect) to produce a moire pattern on a detector. The test object is placed between these gratings, with variations in index of refraction changing the pattern. A third grating in front of an incoherent x-ray source produces an array of coherent sources. With a 150 kV x-ray flash tube as the source, the gratings are placed in a glancing angle setup for performance at ~60 keV. The detector is a gated CCD with a fast scintillator for x-ray conversion. This diagnostic, designed for the Dual-Axis Radiographic Hydrodynamic Test facility (DARHT) at Los Alamos National Laboratory, measures the density profile of dense plasma plumes ejected from beam-target interactions. DARHT has two high-current, pulsed, inductive linear electron accelerators with bremsstrahlung targets at the end of each beam line to create 2-D radiographic images of hydrodynamic tests. One multi-pulse accelerator has up to four beam pulses striking the same target within 2 μs. Computer simulations that model target evolution and ejected material between pulses are used to design these targets for optimal radiographic performance; the x-ray deflectometer will directly measure density gradients in the ejected plumes and provide the first experimental constraints to these models. During the first year, currently underway, the diagnostic systems are being designed. In year two, the flash tube and fast detector will be deployed at DARHT for radiographic imaging while the deflectometer is built and tested on the bench with a continuous source. Finally, in year three, the fast deflectometer will be installed on DARHT and density measurements will be performed.

  4. All-laser-driven Thomson X-ray sources

    NASA Astrophysics Data System (ADS)

    Umstadter, Donald P.

    2015-10-01

    We discuss the development of a new generation of accelerator-based hard X-ray sources driven exclusively by laser light. High-intensity laser pulses serve the dual roles: first, accelerating electrons by laser-driven plasma wakefields, and second, generating X-rays by inverse Compton scattering. Such all-laser-driven X-rays have recently been demonstrated to be energetic, tunable, relatively narrow in bandwidth, short pulsed and well collimated. Such characteristics, especially from a compact source, are highly advantageous for numerous advanced X-ray applications - in metrology, biomedicine, materials, ultrafast phenomena, radiology and fundamental physics.

  5. X-ray Absorption Spectroscopy

    SciTech Connect

    Yano, Junko; Yachandra, Vittal K.

    2009-07-09

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

  6. [The X-Ray Fluorescence Spectrometer Based on Pyroelectric Effect].

    PubMed

    Dong, Yi-fan; Fan, Rui-rui; Guo, Dong-ya; Zhang, Chun-lei; Gao, Min; Wang, Jin-zhou; Liu, Ya-qing; Zhou, Da-wei; Wang, Huan-yu

    2016-02-01

    Pyroelectric X-ray generator is implemented, and an X-ray fluorescence spectrometer is accomplished by combining the pyroelectric X-ray generator with a high energy resolution silicon drift detector. Firstly, the parameters of the X-ray generator are decided by analyzing and calculating the influence of the thickness of the pyroelectriccrystal and the thickness of the target on emitted X-ray. Secondly, the emitted X-ray is measured. The energy of emitted X-ray is from 1 to 27 keV, containing the characteristic X-ray of Cu and Ta, and the max counting rate is more than 3 000 per second. The measurement also proves that the detector of the spectrometer has a high energy resolution which the FWMH is 210 eV at 8. 05 keV. Lastly, samples of Fe, Ti, Cr and high-Ti basalt are analyzed using the spectrometer, and the results are agreed with the elements of the samples. It shows that the spectrometer consisting of a pyroelectric X-ray generator and a silicon drift detector is effective for element analysis. Additionally, because each part of the spectrometer has a small volume, it can be easily modified to a portable one which is suitable for non-destructive, on-site and quick element analysis.

  7. X-ray photonics: Bending X-rays with nanochannels

    NASA Astrophysics Data System (ADS)

    Pelliccia, Daniele

    2016-02-01

    X-ray counterparts of visible light optical elements are notoriously difficult to realize because the refractive index of all materials is close to unity. It has now been demonstrated that curved waveguides fabricated on a silicon chip can channel and deflect X-ray beams by consecutive grazing reflections.

  8. Optics for coherent X-ray applications.

    PubMed

    Yabashi, Makina; Tono, Kensuke; Mimura, Hidekazu; Matsuyama, Satoshi; Yamauchi, Kazuto; Tanaka, Takashi; Tanaka, Hitoshi; Tamasaku, Kenji; Ohashi, Haruhiko; Goto, Shunji; Ishikawa, Tetsuya

    2014-09-01

    Developments of X-ray optics for full utilization of diffraction-limited storage rings (DLSRs) are presented. The expected performance of DLSRs is introduced using the design parameters of SPring-8 II. To develop optical elements applicable to manipulation of coherent X-rays, advanced technologies on precise processing and metrology were invented. With propagation-based coherent X-rays at the 1 km beamline of SPring-8, a beryllium window fabricated with the physical-vapour-deposition method was found to have ideal speckle-free properties. The elastic emission machining method was utilized for developing reflective mirrors without distortion of the wavefronts. The method was further applied to production of diffraction-limited focusing mirrors generating the smallest spot size in the sub-10 nm regime. To enable production of ultra-intense nanobeams at DLSRs, a low-vibration cooling system for a high-heat-load monochromator and advanced diagnostic systems to characterize X-ray beam properties precisely were developed. Finally, new experimental schemes for combinative nano-analysis and spectroscopy realised with novel X-ray optics are discussed.

  9. Ultrafast X-Ray Coherent Control

    SciTech Connect

    Reis, David

    2009-05-01

    This main purpose of this grant was to develop the nascent eld of ultrafast x-ray science using accelerator-based sources, and originally developed from an idea that a laser could modulate the di racting properties of a x-ray di racting crystal on a fast enough time scale to switch out in time a shorter slice from the already short x-ray pulses from a synchrotron. The research was carried out primarily at the Advanced Photon Source (APS) sector 7 at Argonne National Laboratory and the Sub-Picosecond Pulse Source (SPPS) at SLAC; in anticipation of the Linac Coherent Light Source (LCLS) x-ray free electron laser that became operational in 2009 at SLAC (all National User Facilities operated by BES). The research centered on the generation, control and measurement of atomic-scale dynamics in atomic, molecular optical and condensed matter systems with temporal and spatial resolution . It helped develop the ultrafast physics, techniques and scienti c case for using the unprecedented characteristics of the LCLS. The project has been very successful with results have been disseminated widely and in top journals, have been well cited in the eld, and have laid the foundation for many experiments being performed on the LCLS, the world's rst hard x-ray free electron laser.

  10. Polarisation modulation in X-ray binaries

    NASA Astrophysics Data System (ADS)

    Ingram, Adam; Maccarone, Thomas

    2016-07-01

    X-ray polarimetry promises to provide a powerful new lever arm for studying accretion onto black holes with the next generation of X-ray telescopes. I will discuss how polarisation can be used to help constrain the physical origin of quasi-periodic oscillations (QPOs) observed in the X-ray light curves of accreting black holes. QPOs may be signatures of the frame dragging effect: in General Relativity, a spinning black hole twists up the surrounding space-time, causing vertical precession of nearby orbits. In the truncated disc / precessing inner flow model, the entire inner accretion flow precesses as a solid body causing a modulation in the X-ray flux through solid angle and Doppler effects. This model also predicts the observed polarisation of the X-ray signal to vary quasi-periodically. I will summarise our work to model the polarisation signal from a precessing accretion flow, starting with simple assumptions about the emission mechanism but taking General Relativity fully into account. We find that it should be possible to measure the predicted modulation in polarisation degree for a reasonable region of parameter space with a polarimeter capable of detecting ~60 counts per second from a bright black hole binary. I will also show that sensitivity can be greatly improved by correlating the signal with a high count rate reference band signal.

  11. Radiographic X-Ray Pulse Jitter

    SciTech Connect

    Mitton, C. V., Good, D. E., Henderson, D. J., Hogge, K. W.

    2011-01-15

    The Dual Beam Radiographic Facility consists of two identical radiographic sources. Major components of the machines are: Marx generator, water-filled pulse-forming line (PFL), water-filled coaxial transmission line, three-cell inductive voltage adder, and rod-pinch diode. The diode pulse has the following electrical specifications: 2.25-MV, 60-kA, 60-ns. Each source has the following x-ray parameters: 1-mm-diameter spot size, 4-rad at 1 m, 50-ns full width half max. The x-ray pulse is measured with PIN diode detectors. The sources were developed to produce high resolution images on single-shot, high-value experiments. For this application it is desirable to maintain a high level of reproducibility in source output. X-ray pulse jitter is a key metric for analysis of reproducibility. We will give measurements of x-ray jitter for each machine. It is expected that x-ray pulse jitter is predominantly due to PFL switch jitter, and therefore a correlation of the two will be discussed.

  12. Optics for coherent X-ray applications

    PubMed Central

    Yabashi, Makina; Tono, Kensuke; Mimura, Hidekazu; Matsuyama, Satoshi; Yamauchi, Kazuto; Tanaka, Takashi; Tanaka, Hitoshi; Tamasaku, Kenji; Ohashi, Haruhiko; Goto, Shunji; Ishikawa, Tetsuya

    2014-01-01

    Developments of X-ray optics for full utilization of diffraction-limited storage rings (DLSRs) are presented. The expected performance of DLSRs is introduced using the design parameters of SPring-8 II. To develop optical elements applicable to manipulation of coherent X-rays, advanced technologies on precise processing and metrology were invented. With propagation-based coherent X-rays at the 1 km beamline of SPring-8, a beryllium window fabricated with the physical-vapour-deposition method was found to have ideal speckle-free properties. The elastic emission machining method was utilized for developing reflective mirrors without distortion of the wavefronts. The method was further applied to production of diffraction-limited focusing mirrors generating the smallest spot size in the sub-10 nm regime. To enable production of ultra-intense nanobeams at DLSRs, a low-vibration cooling system for a high-heat-load monochromator and advanced diagnostic systems to characterize X-ray beam properties precisely were developed. Finally, new experimental schemes for combinative nano-analysis and spectroscopy realised with novel X-ray optics are discussed. PMID:25177986

  13. Ultra-short wavelength x-ray system

    DOEpatents

    Umstadter, Donald; He, Fei; Lau, Yue-Ying

    2008-01-22

    A method and apparatus to generate a beam of coherent light including x-rays or XUV by colliding a high-intensity laser pulse with an electron beam that is accelerated by a synchronized laser pulse. Applications include x-ray and EUV lithography, protein structural analysis, plasma diagnostics, x-ray diffraction, crack analysis, non-destructive testing, surface science and ultrafast science.

  14. Process and device for x-ray system quality assurance

    SciTech Connect

    Van Pelt, W.F.; Peterson, R.W.

    1982-11-10

    This invention relates to medical radiography test systems, and more particularly to a method and apparatus for providing evaluation of a medical or dental x-ray system consisting of x-ray generator, film and processor on a daily basis and to thereby assure the production of useful radiographs from the system with no need to repeat patient exposure because of problems with the x-ray system.

  15. European XFEL: Soft X-Ray instrumentation

    SciTech Connect

    Molodtsov, S. L.

    2011-12-15

    The currently constructed European X-Ray Free Electron Laser (XFEL) will generate new knowledge in almost all the technical and scientific disciplines that are shaping our daily life-including nanotechnology, medicine, pharmaceutics, chemistry, materials science, power engineering and electronics. On 8 January 2009, civil engineering work (tunnels, shafts, halls) has been started at all three construction sites. In this presentation status and parameters of the European XFEL facility and instrumentation as well as planned research applications particularly in the range of soft X-rays are reviewed.

  16. Single Particle X-ray Diffractive Imaging

    SciTech Connect

    Bogan, M J; Benner, W H; Boutet, S; Rohner, U; Frank, M; Seibert, M; Maia, F; Barty, A; Bajt, S; Riot, V; Woods, B; Marchesini, S; Hau-Riege, S P; Svenda, M; Marklund, E; Spiller, E; Hajdu, J; Chapman, H N

    2007-10-01

    In nanotechnology, strategies for the creation and manipulation of nanoparticles in the gas phase are critically important for surface modification and substrate-free characterization. Recent coherent diffractive imaging with intense femtosecond X-ray pulses has verified the capability of single-shot imaging of nanoscale objects at sub-optical resolutions beyond the radiation-induced damage threshold. By intercepting electrospray-generated particles with a single 15 femtosecond soft-X-ray pulse, we demonstrate diffractive imaging of a nanoscale specimen in free flight for the first time, an important step toward imaging uncrystallized biomolecules.

  17. Tokamak Spectroscopy for X-Ray Astronomy

    NASA Technical Reports Server (NTRS)

    Fournier, Kevin B.; Finkenthal, M.; Pacella, D.; May, M. J.; Soukhanovskii, V.; Mattioli, M.; Leigheb, M.; Rice, J. E.

    2000-01-01

    This paper presents the measured x-ray and Extreme Ultraviolet (XUV) spectra of three astrophysically abundant elements (Fe, Ca and Ne) from three different tokamak plasmas. In every case, each spectrum touches on an issue of atomic physics that is important for simulation codes to be used in the analysis of high spectral resolution data from current and future x-ray telescopes. The utility of the tokamak as a laboratory test bed for astrophysical data is demonstrated. Simple models generated with the HULLAC suite of codes demonstrate how the atomic physics issues studied can affect the interpretation of astrophysical data.

  18. X-Ray Calorimeter Arrays for Astrophysics

    NASA Technical Reports Server (NTRS)

    Kilbourne, Caroline A.

    2009-01-01

    High-resolution x-ray spectroscopy is a powerful tool for studying the evolving universe. The grating spectrometers on the XMM and Chandra satellites started a new era in x-ray astronomy, but there remains a need for instrumentation that can provide higher spectral resolution with high throughput in the Fe-K band (around 6 keV) and can enable imaging spectroscopy of extended sources, such as supernova remnants and galaxy clusters. The instrumentation needed is a broad-band imaging spectrometer - basically an x-ray camera that can distinguish tens of thousands of x-ray colors. The potential benefits to astrophysics of using a low-temperature calorimeter to determine the energy of an incident x-ray photon via measurement of a small change in temperature was first articulated by S. H. Moseley over two decades ago. In the time since, technological progress has been steady, though full realization in an orbiting x-ray telescope is still awaited. A low-temperature calorimeter can be characterized by the type of thermometer it uses, and three types presently dominate the field. The first two types are temperature-sensitive resistors - semiconductors in the metal-insulator transition and superconductors operated in the superconducting-normal transition. The third type uses a paramagnetic thermometer. These types can be considered the three generations of x-ray calorimeters; by now each has demonstrated a resolving power of 2000 at 6 keV, but only a semiconductor calorimeter system has been developed to spaceflight readiness. The Soft X-ray Spectrometer on Astro-H, expected to launch in 2013, will use an array of silicon thermistors with I-IgTe x-ray absorbers that will operate at 50 mK. Both the semiconductor and superconductor calorimeters have been implemented in small arrays, kilo-pixel arrays of the superconducting calorimeters are just now being produced, and it is anticipated that much larger arrays will require the non-dissipative advantage of magnetic thermometers.

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

    NASA Astrophysics Data System (ADS)

    Lengeler, Bruno; Schroer, Christian G.; Benner, Boris; Günzler, Til Florian; Kuhlmann, Marion; Tümmler, Johannes; Simionovici, Alexandre S.; Drakopoulos, Michael; Snigirev, Anatoly; Snigireva, Irina

    2001-07-01

    Refractive X-ray lenses, considered for a long time as unfeasible, have been realized with a rotational parabolic profile at our institute: The main features of the new lenses are: they focus in two directions and are free of spherical aberration. By varying the number of individual lenses in the stack the focal length can be chosen in a typical range from 0.5 to 2 m for photon energies between about 6 and 60 keV. The aperture of the lens is about 1 mm matching the angular divergence of undulator beams at 3d generation synchrotron radiation sources. They cope without problems with the heat load from the white beam of an undulator. Finally, they are easy to align and to operate. Refractive X-ray lenses can be used with hard X-rays in the same way as glass lenses can be used for visible light, if it is take into account that the numerical aperture is small (of the order 10 -4). Being high-quality optical elements, the refractive X-ray lenses can be used for generating a focal spot in the μm range with a gain of a factor 1000 and more, or for imaging purposes as in a hard X-ray microscope. Recent examples from microanalysis, microtomography, fluorescence tomography, X-ray microscopy will be shown to demonstrate the state of the art. Possible new developments will be discussed.

  20. EPR-Spin Trapping and Flow Cytometric Studies of Free Radicals Generated Using Cold Atmospheric Argon Plasma and X-Ray Irradiation in Aqueous Solutions and Intracellular Milieu

    PubMed Central

    Uchiyama, Hidefumi; Zhao, Qing-Li; Hassan, Mariame Ali; Andocs, Gabor; Nojima, Nobuyuki; Takeda, Keigo; Ishikawa, Kenji; Hori, Masaru; Kondo, Takashi

    2015-01-01

    Electron paramagnetic resonance (EPR)-spin trapping and flow cytometry were used to identify free radicals generated using argon-cold atmospheric plasma (Ar-CAP) in aqueous solutions and intracellularly in comparison with those generated by X-irradiation. Ar-CAP was generated using a high-voltage power supply unit with low-frequency excitation. The characteristics of Ar-CAP were estimated by vacuum UV absorption and emission spectra measurements. Hydroxyl (·OH) radicals and hydrogen (H) atoms in aqueous solutions were identified with the spin traps 5,5-dimethyl-1-pyrroline N-oxide (DMPO), 3,3,5,5-tetramethyl-1-pyrroline-N-oxide (M4PO), and phenyl N-t-butylnitrone (PBN). The occurrence of Ar-CAP-induced pyrolysis was evaluated using the spin trap 3,5-dibromo-4-nitrosobenzene sulfonate (DBNBS) in aqueous solutions of DNA constituents, sodium acetate, and L-alanine. Human lymphoma U937 cells were used to study intracellular oxidative stress using five fluorescent probes with different affinities to a number of reactive species. The analysis and quantification of EPR spectra revealed the formation of enormous amounts of ·OH radicals using Ar-CAP compared with that by X-irradiation. Very small amounts of H atoms were detected whereas nitric oxide was not found. The formation of ·OH radicals depended on the type of rare gas used and the yield correlated inversely with ionization energy in the order of krypton > argon = neon > helium. No pyrolysis radicals were detected in aqueous solutions exposed to Ar-CAP. Intracellularly, ·OH, H2O2, which is the recombination product of ·OH, and OCl- were the most likely formed reactive oxygen species after exposure to Ar-CAP. Intracellularly, there was no practical evidence for the formation of NO whereas very small amounts of superoxides were formed. Despite the superiority of Ar-CAP in forming ·OH radicals, the exposure to X-rays proved more lethal. The mechanism of free radical formation in aqueous solutions and an

  1. EPR-Spin Trapping and Flow Cytometric Studies of Free Radicals Generated Using Cold Atmospheric Argon Plasma and X-Ray Irradiation in Aqueous Solutions and Intracellular Milieu.

    PubMed

    Uchiyama, Hidefumi; Zhao, Qing-Li; Hassan, Mariame Ali; Andocs, Gabor; Nojima, Nobuyuki; Takeda, Keigo; Ishikawa, Kenji; Hori, Masaru; Kondo, Takashi

    2015-01-01

    Electron paramagnetic resonance (EPR)-spin trapping and flow cytometry were used to identify free radicals generated using argon-cold atmospheric plasma (Ar-CAP) in aqueous solutions and intracellularly in comparison with those generated by X-irradiation. Ar-CAP was generated using a high-voltage power supply unit with low-frequency excitation. The characteristics of Ar-CAP were estimated by vacuum UV absorption and emission spectra measurements. Hydroxyl (·OH) radicals and hydrogen (H) atoms in aqueous solutions were identified with the spin traps 5,5-dimethyl-1-pyrroline N-oxide (DMPO), 3,3,5,5-tetramethyl-1-pyrroline-N-oxide (M4PO), and phenyl N-t-butylnitrone (PBN). The occurrence of Ar-CAP-induced pyrolysis was evaluated using the spin trap 3,5-dibromo-4-nitrosobenzene sulfonate (DBNBS) in aqueous solutions of DNA constituents, sodium acetate, and L-alanine. Human lymphoma U937 cells were used to study intracellular oxidative stress using five fluorescent probes with different affinities to a number of reactive species. The analysis and quantification of EPR spectra revealed the formation of enormous amounts of ·OH radicals using Ar-CAP compared with that by X-irradiation. Very small amounts of H atoms were detected whereas nitric oxide was not found. The formation of ·OH radicals depended on the type of rare gas used and the yield correlated inversely with ionization energy in the order of krypton > argon = neon > helium. No pyrolysis radicals were detected in aqueous solutions exposed to Ar-CAP. Intracellularly, ·OH, H2O2, which is the recombination product of ·OH, and OCl- were the most likely formed reactive oxygen species after exposure to Ar-CAP. Intracellularly, there was no practical evidence for the formation of NO whereas very small amounts of superoxides were formed. Despite the superiority of Ar-CAP in forming ·OH radicals, the exposure to X-rays proved more lethal. The mechanism of free radical formation in aqueous solutions and an

  2. X-Ray Exam: Wrist

    MedlinePlus

    ... tissues and the ends of the forearm bones (radius and ulna) and eight small wrist bones (carpal bones). The X-ray image is black and white. Dense structures that block the passage of the X-ray beam through the body, such as the bones, appear white on the image. Softer ...

  3. X-ray based extensometry

    NASA Technical Reports Server (NTRS)

    Jordan, E. H.; Pease, D. M.

    1988-01-01

    A totally new method of extensometry using an X-ray beam was proposed. The intent of the method is to provide a non-contacting technique that is immune to problems associated with density variations in gaseous environments that plague optical methods. X-rays are virtually unrefractable even by solids. The new method utilizes X-ray induced X-ray fluorescence or X-ray induced optical fluorescence of targets that have melting temperatures of over 3000 F. Many different variations of the basic approaches are possible. In the year completed, preliminary experiments were completed which strongly suggest that the method is feasible. The X-ray induced optical fluorescence method appears to be limited to temperatures below roughly 1600 F because of the overwhelming thermal optical radiation. The X-ray induced X-ray fluorescence scheme appears feasible up to very high temperatures. In this system there will be an unknown tradeoff between frequency response, cost, and accuracy. The exact tradeoff can only be estimated. It appears that for thermomechanical tests with cycle times on the order of minutes a very reasonable system may be feasible. The intended applications involve very high temperatures in both materials testing and monitoring component testing. Gas turbine engines, rocket engines, and hypersonic vehicles (NASP) all involve measurement needs that could partially be met by the proposed technology.

  4. Dual x-ray absorptiometry

    NASA Astrophysics Data System (ADS)

    Altman, Albert; Aaron, Ronald

    2011-04-01

    Dual x-ray absorptiometry is widely used in analyzing body composition and imaging. We discuss the physics of the method and exhibit its limitations and show it is related to the Compton and photoelectric contributions to the x-ray absorption coefficients of materials.

  5. Transient and Capillary Collisional X-ray Laser

    SciTech Connect

    Shlyaptsev, V N; Dunn, J; Fournier, K B; Moon, S; Osterheld, A L; Rocca, J J; Detering, F; Rozmus, W; Matte, J P; Fiedorowicz, H; Bartnik, A; Kanouff, M

    2001-12-17

    In this work we report our numerical modeling results of laser-generated transient inversion and capillary discharge X-ray lasers. In the search for more efficient X-ray lasers we look closely at other approaches in conjunction with experiments at LLNL. In the search for improved X-ray lasers we perform modeling and experimental investigations of low density targets including gas puff targets. We have found the importance of plasma kinetics in transient X-ray lasers by expanding the physical model beyond hydrodynamics approach with Particle In Cell (PIC) and Fokker-Planck codes. The evidence of the Langdon effect was inferred from the recent experimental data obtained with the Ni-like Pd X-ray laser. We continue modeling different kinds of capillary discharge plasma configurations directed toward shorter wavelength X-ray lasers, plasma diagnostics and other applications.

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

    DOEpatents

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

    1995-01-17

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

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

    DOEpatents

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

    1995-01-01

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

  8. X-ray shearing interferometer

    DOEpatents

    Koch, Jeffrey A.

    2003-07-08

    An x-ray interferometer for analyzing high density plasmas and optically opaque materials includes a point-like x-ray source for providing a broadband x-ray source. The x-rays are directed through a target material and then are reflected by a high-quality ellipsoidally-bent imaging crystal to a diffraction grating disposed at 1.times. magnification. A spherically-bent imaging crystal is employed when the x-rays that are incident on the crystal surface are normal to that surface. The diffraction grating produces multiple beams which interfere with one another to produce an interference pattern which contains information about the target. A detector is disposed at the position of the image of the target produced by the interfering beams.

  9. X-Ray Tomographic Reconstruction

    SciTech Connect

    Bonnie Schmittberger

    2010-08-25

    Tomographic scans have revolutionized imaging techniques used in medical and biological research by resolving individual sample slices instead of several superimposed images that are obtained from regular x-ray scans. X-Ray fluorescence computed tomography, a more specific tomography technique, bombards the sample with synchrotron x-rays and detects the fluorescent photons emitted from the sample. However, since x-rays are attenuated as they pass through the sample, tomographic scans often produce images with erroneous low densities in areas where the x-rays have already passed through most of the sample. To correct for this and correctly reconstruct the data in order to obtain the most accurate images, a program employing iterative methods based on the inverse Radon transform was written. Applying this reconstruction method to a tomographic image recovered some of the lost densities, providing a more accurate image from which element concentrations and internal structure can be determined.

  10. EXACT - The Solar X-Ray Spectrometer CubeSat

    NASA Astrophysics Data System (ADS)

    Knuth, Trevor; Glesener, Lindsay; Gebre-Egziabher, Demoz; Vogt, Ryan; Denis, Charles; Weiher, Hannah; Runnels, Joel; Vievering, Juliana

    2016-05-01

    The Experiment for X-ray Characterization and Timing (EXACT) mission will be a CubeSat based hard X-ray spectrometer used for viewing solar flares with high time precision. Solar flares and the related coronal mass ejections affect space weather and the near-Earth environment. EXACT can study the hard X-rays generated by the Sun in the declining phase of Solar Cycle 24 in order to probe electron acceleration in solar eruptive events while also serving as a precursor to future hard X-ray spectrometers that could monitor the Sun continuously.

  11. X-ray monitoring optical elements

    SciTech Connect

    Stoupin, Stanislav; Shvydko, Yury; Katsoudas, John; Blank, Vladimir D.; Terentyev, Sergey A.

    2016-12-27

    An X-ray article and method for analyzing hard X-rays which have interacted with a test system. The X-ray article is operative to diffract or otherwise process X-rays from an input X-ray beam which have interacted with the test system and at the same time provide an electrical circuit adapted to collect photoelectrons emitted from an X-ray optical element of the X-ray article to analyze features of the test system.

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

    PubMed

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

    2015-05-01

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

  13. Hetero-site-specific X-ray pump-probe spectroscopy for femtosecond intramolecular dynamics

    PubMed Central

    Picón, A.; Lehmann, C. S.; Bostedt, C.; Rudenko, A.; Marinelli, A.; Osipov, T.; Rolles, D.; Berrah, N.; Bomme, C.; Bucher, M.; Doumy, G.; Erk, B.; Ferguson, K. R.; Gorkhover, T.; Ho, P. J.; Kanter, E. P.; Krässig, B.; Krzywinski, J.; Lutman, A. A.; March, A. M.; Moonshiram, D.; Ray, D.; Young, L.; Pratt, S. T.; Southworth, S. H.

    2016-01-01

    New capabilities at X-ray free-electron laser facilities allow the generation of two-colour femtosecond X-ray pulses, opening the possibility of performing ultrafast studies of X-ray-induced phenomena. Particularly, the experimental realization of hetero-site-specific X-ray-pump/X-ray-probe spectroscopy is of special interest, in which an X-ray pump pulse is absorbed at one site within a molecule and an X-ray probe pulse follows the X-ray-induced dynamics at another site within the same molecule. Here we show experimental evidence of a hetero-site pump-probe signal. By using two-colour 10-fs X-ray pulses, we are able to observe the femtosecond time dependence for the formation of F ions during the fragmentation of XeF2 molecules following X-ray absorption at the Xe site. PMID:27212390

  14. Hetero-site-specific X-ray pump-probe spectroscopy for femtosecond intramolecular dynamics

    SciTech Connect

    Picón, A.; Lehmann, C. S.; Bostedt, C.; Rudenko, A.; Marinelli, A.; Osipov, T.; Rolles, D.; Berrah, N.; Bomme, C.; Bucher, M.; Doumy, G.; Erk, B.; Ferguson, K. R.; Gorkhover, T.; Ho, P. J.; Kanter, E. P.; Krässig, B.; Krzywinski, J.; Lutman, A. A.; March, A. M.; Moonshiram, D.; Ray, D.; Young, L.; Pratt, S. T.; Southworth, S. H.

    2016-05-23

    New capabilities at X-ray free-electron laser facilities allow the generation of two-colour femtosecond X-ray pulses, opening the possibility of performing ultrafast studies of X-ray-induced phenomena. Specifically, the experimental realization of hetero-site-specific X-ray-pump/X-ray-probe spectroscopy is of special interest, in which an X-ray pump pulse is absorbed at one site within a molecule and an X-ray probe pulse follows the X-ray-induced dynamics at another site within the same molecule. In this paper, we show experimental evidence of a hetero-site pump-probe signal. By using two-colour 10-fs X-ray pulses, we are able to observe the femtosecond time dependence for the formation of F ions during the fragmentation of XeF2 molecules following X-ray absorption at the Xe site.

  15. Hetero-site-specific X-ray pump-probe spectroscopy for femtosecond intramolecular dynamics.

    PubMed

    Picón, A; Lehmann, C S; Bostedt, C; Rudenko, A; Marinelli, A; Osipov, T; Rolles, D; Berrah, N; Bomme, C; Bucher, M; Doumy, G; Erk, B; Ferguson, K R; Gorkhover, T; Ho, P J; Kanter, E P; Krässig, B; Krzywinski, J; Lutman, A A; March, A M; Moonshiram, D; Ray, D; Young, L; Pratt, S T; Southworth, S H

    2016-05-23

    New capabilities at X-ray free-electron laser facilities allow the generation of two-colour femtosecond X-ray pulses, opening the possibility of performing ultrafast studies of X-ray-induced phenomena. Particularly, the experimental realization of hetero-site-specific X-ray-pump/X-ray-probe spectroscopy is of special interest, in which an X-ray pump pulse is absorbed at one site within a molecule and an X-ray probe pulse follows the X-ray-induced dynamics at another site within the same molecule. Here we show experimental evidence of a hetero-site pump-probe signal. By using two-colour 10-fs X-ray pulses, we are able to observe the femtosecond time dependence for the formation of F ions during the fragmentation of XeF2 molecules following X-ray absorption at the Xe site.

  16. Hetero-site-specific X-ray pump-probe spectroscopy for femtosecond intramolecular dynamics

    DOE PAGES

    Picón, A.; Lehmann, C. S.; Bostedt, C.; ...

    2016-05-23

    New capabilities at X-ray free-electron laser facilities allow the generation of two-colour femtosecond X-ray pulses, opening the possibility of performing ultrafast studies of X-ray-induced phenomena. Specifically, the experimental realization of hetero-site-specific X-ray-pump/X-ray-probe spectroscopy is of special interest, in which an X-ray pump pulse is absorbed at one site within a molecule and an X-ray probe pulse follows the X-ray-induced dynamics at another site within the same molecule. In this paper, we show experimental evidence of a hetero-site pump-probe signal. By using two-colour 10-fs X-ray pulses, we are able to observe the femtosecond time dependence for the formation of F ionsmore » during the fragmentation of XeF2 molecules following X-ray absorption at the Xe site.« less

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

    SciTech Connect

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

    2012-06-18

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

  18. Generation of runaway electrons and X-ray emission during breakdown of atmospheric-pressure air by voltage pulses with an ∼0.5-μs front duration

    SciTech Connect

    Kostyrya, I. D.; Tarasenko, V. F.

    2015-03-15

    Results are presented from experiments on the generation of runaway electron beams and X-ray emission in atmospheric-pressure air by using voltage pulses with an ∼0.5-μs front duration. It is shown that the use of small-curvature-radius spherical cathodes (or other cathodes with small curvature radii) decreases the intensity of the runaway electron beam and X-ray emission. It is found that, at sufficiently high voltages at the electrode gap (U{sub m} ∼ 100 kV), the gap breakdown, the formation of a spark channel, and the generation of a runaway electron beam occur over less than 10 ns. At high values of U{sub m} behind the anode that were reached by increasing the cathode size and the electrode gap length, a supershort avalanche electron beam with a full width at half-maximum (FWHM) of up to ∼100 ps was detected. At voltages of ∼50 kV, the second breakdown regime was revealed in which a runaway electron beam with an FWHM of ∼2 ns was generated, whereas the FWHM of the X-ray pulse increased to ∼100 ns. It is established that the energy of the bulk of runaway electrons decreases with increasing voltage front duration and is ⩽30 keV in the first regime and ⩽10 keV in the second regime.

  19. Studies on the effective energy of x-rays generated by ECR and their use for the calibration of thermoluminescent dosimeter badges in low energy region

    SciTech Connect

    Baskaran, R.; Selvakumaran, T.S.

    2005-04-01

    The effective energy of electron cyclotron resonance (ECR) x-ray source has been altered by keeping a target disk at the cavity wall in the exit port. The source has been tuned for the effective energy of 40 and 70 keV. The use of the source for the calibration of thermoluminescent dosimeter badges in the low energy region (<150 keV) has been explored.

  20. High Resolution X-ray-Induced Acoustic Tomography

    PubMed Central

    Xiang, Liangzhong; Tang, Shanshan; Ahmad, Moiz; Xing, Lei

    2016-01-01

    Absorption based CT imaging has been an invaluable tool in medical diagnosis, biology, and materials science. However, CT requires a large set of projection data and high radiation dose to achieve superior image quality. In this letter, we report a new imaging modality, X-ray Induced Acoustic Tomography (XACT), which takes advantages of high sensitivity to X-ray absorption and high ultrasonic resolution in a single modality. A single projection X-ray exposure is sufficient to generate acoustic signals in 3D space because the X-ray generated acoustic waves are of a spherical nature and propagate in all directions from their point of generation. We demonstrate the successful reconstruction of gold fiducial markers with a spatial resolution of about 350 μm. XACT reveals a new imaging mechanism and provides uncharted opportunities for structural determination with X-ray. PMID:27189746