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1

Femtosecond diffractive imaging with a soft-X-ray free-electron laser  

E-Print Network [OSTI]

LETTERS Femtosecond diffractive imaging with a soft-X-ray free-electron laser HENRY N. CHAPMAN1 of this principle using the FLASH soft-X-ray free-electron laser. An intense 25 fs, 4 Ã? 1013 W cm-2 pulse by one10 . X-ray free-electron lasers (FELs) are expected to permit diffractive imaging at high

Loss, Daniel

2

Fundamental physics at an X-ray free electron laser  

E-Print Network [OSTI]

X-ray free electron lasers (FELs) have been proposed to be constructed both at SLAC in the form of the so-called Linac Coherent Light Source as well as at DESY, where the so-called XFEL laboratory is part of the design of the electron-positron linear collider TESLA. In addition to the immediate applications in condensed matter physics, chemistry, material science, and structural biology, X-ray FELs may be employed also to study some physics issues of fundamental nature. In this context, one may mention the boiling of the vacuum (Schwinger pair creation in an external field), horizon physics (Unruh effect), and axion production. We review these X-ray FEL opportunities of fundamental physics and discuss the necessary technological improvements in order to achieve these goals.

A. Ringwald

2001-12-19T23:59:59.000Z

3

The History of X-ray Free-Electron Lasers  

SciTech Connect (OSTI)

The successful lasing at the SLAC National Accelerator Laboratory of the Linear Coherent Light Source (LCLS), the first X-ray free-electron laser (X-ray FEL), in the wavelength range 1.5 to 15 {angstrom}, pulse duration of 60 to few femtoseconds, number of coherent photons per pulse from 10{sup 13} to 10{sup 11}, is a landmark event in the development of coherent electromagnetic radiation sources. Until now electrons traversing an undulator magnet in a synchrotron radiation storage ring provided the best X-ray sources. The LCLS has set a new standard, with a peak X-ray brightness higher by ten orders of magnitudes and pulse duration shorter by three orders of magnitudes. LCLS opens a new window in the exploration of matter at the atomic and molecular scales of length and time. Taking a motion picture of chemical processes in a few femtoseconds or less, unraveling the structure and dynamics of complex molecular systems, like proteins, are some of the exciting experiments made possible by LCLS and the other X-ray FELs now being built in Europe and Asia. In this paper, we describe the history of the many theoretical, experimental and technological discoveries and innovations, starting from the 1960s and 1970s, leading to the development of LCLS.

Pellegrini, C.; /UCLA /SLAC; ,

2012-06-28T23:59:59.000Z

4

A compact x-ray free electron laser  

SciTech Connect (OSTI)

We present a design concept and simulation of the performance of a compact x-ray, free electron laser driven by ultra-high gradient rf-linacs. The accelerator design is based on recent advances in high gradient technology by a LLNL/SLAC/LBL collaboration and on the development of bright, high current electron sources by BNL and LANL. The GeV electron beams generated with such accelerators can be converted to soft x-rays in the range from 2--10 nm by passage through short period, high field strength wigglers as are being designed at Rocketdyne Linear light sources of this type can produce trains of picosecond (or shorter) pulses of extremely high spectral brilliance suitablee for flash holography of biological specimens in vivo and for studies of fast chemical reactions. 12 refs., 8 figs., 4 tabs.

Barletta, W.A. (California Univ., Los Angeles, CA (USA). Center for Advanced Accelerators Physics Lawrence Livermore National Lab., CA (USA)); Atac, M.; Cline, D.B.; Kolonko, J. (California Univ., Los Angeles, CA (USA). Center for Advanced Accelerators Physics); Bhowmik, A.; Bobbs, B.; Cover, R.A.; Dixon, F.P.; Rakowsky, G. (Rockwell International Corp., Canoga Park, CA (USA). Rocketdyne Div.); Gallardo

1988-01-01T23:59:59.000Z

5

A compact x-ray free electron laser  

SciTech Connect (OSTI)

We present a design concept and simulation of the performance of a compact x-ray, free electron laser driven by ultra-high gradient rf-linacs. The accelerator design is based on recent advances in high gradient technology by a LLNL/SLAC/LBL collaboration and on the development of bright, high current electron sources by BNL and LANL. The GeV electron beams generated with such accelerators can be concerted to soft x-rays in the range from 2--10 nm by passage through short period, high fields strength wigglers as are being designed at Rocketdyne. Linear light sources of this type can produce trains of picosecond (or shorter) pulses of extremely high spectral brilliance suitable for flash holography of biological specimens in vivo and for studies of fast chemical reactions. 12 refs., 8 figs., 4 tabs.

Barletta, W.; Attac, M.; Cline, D.B.; Kolonko, J.; Wang, X.; Bhowmik, A.; Bobbs, B.; Cover, R.A.; Dixon, F.P.; Rakowsky, G.; Gallardo, J.; Pellegrini, C.; Westenskow, G.

1988-09-09T23:59:59.000Z

6

Density gradient free electron collisionally excited X-ray laser  

DOE Patents [OSTI]

An operational X-ray laser (30) is provided that amplifies 3p-3s transition X-ray radiation along an approximately linear path. The X-ray laser (30) is driven by a high power optical laser. The driving line focused optical laser beam (32) illuminates a free-standing thin foil (34) that may be associated with a substrate (36) for improved structural integrity. This illumination produces a generally cylindrically shaped plasma having an essentially uniform electron density and temperature, that exists over a long period of time, and provides the X-ray laser gain medium. The X-ray laser (30) may be driven by more than one optical laser beam (32, 44). The X-ray laser (30) has been successfully demonstrated to function in a series of experimental tests.

Campbell, Edward M. (Pleasanton, CA); Rosen, Mordecai D. (Berkeley, CA)

1989-01-01T23:59:59.000Z

7

Density gradient free electron collisionally excited x-ray laser  

DOE Patents [OSTI]

An operational x-ray laser is provided that amplifies 3p-3s transition x-ray radiation along an approximately linear path. The x-ray laser is driven by a high power optical laser. The driving line focused optical laser beam illuminates a free-standing thin foil that may be associated with a substrate for improved structural integrity. This illumination produces a generally cylindrically shaped plasma having an essentially uniform electron density and temperature, that exists over a long period of time, and provides the x-ray laser gain medium. The x-ray laser may be driven by more than one optical laser beam. The x-ray laser has been successfully demonstrated to function in a series of experimental tests.

Campbell, E.M.; Rosen, M.D.

1984-11-29T23:59:59.000Z

8

The World's First Free-Electron X-ray Laser | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

First Free-Electron X-ray Laser First Free-Electron X-ray Laser The World's First Free-Electron X-ray Laser August 17, 2010 - 6:19pm Addthis The World's First Free-Electron X-ray Laser John Schueler John Schueler Former New Media Specialist, Office of Public Affairs Yesterday, Secretary Chu participated in the dedication of the world's first free-electron and most powerful X-ray laser, the Linac Coherent Light Source (LCLS). In light of this occasion (pun intended), we posted an in-depth look at the innovative nature of this new instrument and its potential to tackle some of life's biggest mysteries. The Secretary seemed just as geeked about the possibilities of the LCLS, stating that "this is a new instrument that will enable us to see the structure of materials that we could not determine by any other means ... Knowing those

9

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

SciTech Connect (OSTI)

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

Katayama, Tetsuo; Togashi, Tadashi; Tono, Kensuke; Kameshima, Takashi [Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan)] [Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Inubushi, Yuichi; Sato, Takahiro; Hatsui, Takaki; Yabashi, Makina [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan)] [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Obara, Yuki; Misawa, Kazuhiko [Department of Applied Physics, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588 (Japan)] [Department of Applied Physics, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588 (Japan); Bhattacharya, Atanu; Kurahashi, Naoya [Department of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho, Sakyo-ku, Kyoto 606-8502 (Japan)] [Department of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho, Sakyo-ku, Kyoto 606-8502 (Japan); Ogi, Yoshihiro [Molecular Reaction Dynamics Research Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako 351-0198 (Japan)] [Molecular Reaction Dynamics Research Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako 351-0198 (Japan); Suzuki, Toshinori [Department of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho, Sakyo-ku, Kyoto 606-8502 (Japan) [Department of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho, Sakyo-ku, Kyoto 606-8502 (Japan); Molecular Reaction Dynamics Research Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako 351-0198 (Japan)

2013-09-23T23:59:59.000Z

10

The European X-ray Free-Electron Laser: A Progress Report | Stanford...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

SLAC, Redtail Conference Room (901-108) M. Altarelli, European XFEL GmbH, Hamburg, Germany The present status of the construction of the European X-ray Free-Electron Laser in...

11

Feasibility considerations of a soft-x-ray distributed feedback laser pumped by an x-ray free electron laser  

E-Print Network [OSTI]

We discuss the feasibility of a soft-x-ray distributed feedback laser (DFL) pumped by an x-ray free electron laser (X-FEL). The DFL under consideration is a Mg/SiC bi-layered Bragg reflector pumped by a single X-FEL bunch at 57.4 eV, stimulating the Mg L2,3 emission at 49 eV corresponding to the 3s-3d â??2p1/2,3/2 transition. Based on a model developed by Yariv and Yeh and an extended coupled-wave theory, we show that it would be possible to obtain a threshold gain compatible with the pumping provided by available X-FEL facilities.

André, Jean-Michel; Jonnard, Philippe

2014-01-01T23:59:59.000Z

12

Toward atomic resolution diffractive imaging of isolated molecules with x-ray free-electron lasers  

E-Print Network [OSTI]

We give a detailed account of the theoretical analysis and the experimental results of an x-ray-diffraction experiment on quantum-state selected and strongly laser-aligned gas-phase ensembles of the prototypical large asymmetric rotor molecule 2,5-diiodobenzonitrile, performed at the Linac Coherent Light Source [Phys. Rev. Lett. 112, 083002 (2014)]. This experiment is the first step toward coherent diffractive imaging of structures and structural dynamics of isolated molecules at atomic resolution, i. e., picometers and femtoseconds, using x-ray free-electron lasers.

Stern, Stephan; Filsinger, Frank; Rouzée, Arnaud; Rudenko, Artem; Johnsson, Per; Martin, Andrew V; Barty, Anton; Bostedt, Christoph; Bozek, John D; Coffee, Ryan N; Epp, Sascha; Erk, Benjamin; Foucar, Lutz; Hartmann, Robert; Kimmel, Nils; Kühnel, Kai-Uwe; Maurer, Jochen; Messerschmidt, Marc; Rudek, Benedikt; Starodub, Dmitri G; Thøgersen, Jan; Weidenspointner, Georg; White, Thomas A; Stapelfeldt, Henrik; Rolles, Daniel; Chapman, Henry N; Küpper, Jochen

2014-01-01T23:59:59.000Z

13

Dominant Secondary Nuclear Photoexcitation with the X-ray Free Electron Laser  

E-Print Network [OSTI]

The new regime of resonant nuclear photoexcitation rendered possible by x-ray free electron laser beams interacting with solid state targets is investigated theoretically. Our results unexpectedly show that secondary processes coupling nuclei to the atomic shell in the created cold high-density plasma can dominate direct photoexcitation. As an example we discuss the case of $^{93m}$Mo isomer depletion for which nuclear excitation by electron capture as secondary process is shown to be orders of magnitude more efficient than the direct laser-nucleus interaction. General arguments revisiting the role of the x-ray free electron laser in nuclear experiments involving solid-state targets are further deduced.

Jonas Gunst; Yuri A. Litvinov; Christoph H. Keitel; Adriana Pálffy

2014-02-27T23:59:59.000Z

14

Three-dimensional manipulation of electron beam phase space for seeding soft x-ray free-electron lasers  

E-Print Network [OSTI]

In this letter, a simple technique is proposed to induce strong density modulation into the electron beam with small energy modulation. By using the combination of a transversely dispersed electron beam and a wave-front tilted seed laser, three-dimensional manipulation of the electron beam phase space can be utilized to significantly enhance the micro-bunching of seeded free-electron laser schemes, which will improve the performance and extend the short-wavelength range of a single-stage seeded free-electron laser. Theoretical analysis and numerical simulations demonstrate the capability of the proposed technique in a soft x-ray free-electron laser.

Feng, Chao; Deng, Haixiao; Zhao, Zhentang

2014-01-01T23:59:59.000Z

15

Spectrometer for X-ray emission experiments at FERMI free-electron-laser  

SciTech Connect (OSTI)

A portable and compact photon spectrometer to be used for photon in-photon out experiments, in particular x-ray emission spectroscopy, is presented. The instrument operates in the 25–800 eV energy range to cover the full emissions of the FEL1 and FEL2 stages of FERMI. The optical design consists of two interchangeable spherical varied-lined-spaced gratings and a CCD detector. Different input sections can be accommodated, with/without an entrance slit and with/without an additional relay mirror, that allow to mount the spectrometer in different end-stations and at variable distances from the target area both at synchrotron and at free-electron-laser beamlines. The characterization on the Gas Phase beamline at ELETTRA Synchrotron (Italy) is presented.

Poletto, L., E-mail: poletto@dei.unipd.it; Frassetto, F.; Miotti, P. [CNR - Institute of Photonics and Nanotechnologies (CNR-IFN), via Trasea 7, I-35131 Padova (Italy); Di Cicco, A.; Iesari, F. [Physics Division, School of Science and Technology, Università di Camerino, I-62032 Camerino (Italy); Finetti, P. [ELETTRA - Sincrotrone Trieste, Basovizza Area Science Park, S. S. 14 - km 163,5, I-34149, Basovizza (TS) (Italy); Grazioli, C. [Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, I-34127 Trieste (Italy); CNR-Istituto Officina dei Materiali (CNR-IOM), Laboratorio TASC, I-34149 Trieste (Italy); Kivimäki, A. [CNR-Istituto Officina dei Materiali (CNR-IOM), Laboratorio TASC, I-34149 Trieste (Italy); Stagira, S. [Politecnico di Milano – Department of Physics, I-20133 Milano (Italy); Coreno, M. [ELETTRA - Sincrotrone Trieste, Basovizza Area Science Park, S. S. 14 - km 163,5, I-34149, Basovizza (TS) (Italy); CNR – Istituto di Struttura della Materia (CNR-ISM), UOS Basovizza, I-34149 Trieste (Italy)

2014-10-15T23:59:59.000Z

16

Single-Molecule Imaging with X-Ray Free-Electron Lasers: Dream or Reality?  

SciTech Connect (OSTI)

X-ray free-electron lasers (XFEL) are revolutionary photon sources, whose ultrashort, brilliant pulses are expected to allow single-molecule diffraction experiments providing structural information on the atomic length scale of nonperiodic objects. This ultimate goal, however, is currently hampered by several challenging questions basically concerning sample damage, Coulomb explosion, and the role of nonlinearity. By employing an original ab initio approach, we address these issues showing that XFEL-based single-molecule imaging will be only possible with a few-hundred long attosecond pulses, due to significant radiation damage and the formation of preferred multisoliton clusters which reshape the overall electronic density of the molecular system at the femtosecond scale.

Fratalocchi, A. [PRIMALIGHT, Faculty of Electrical Engineering, Applied Mathematics and Computational Science, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900 (Saudi Arabia)] [Department of Physics, Sapienza University of Rome, P.le A. Moro 2, 00185, Rome (Italy); Ruocco, G. [Department of Physics, Sapienza University of Rome, P.le A. Moro 2, 00185, Rome (Italy)] [IPCF-CNR, c/o Department of Physics, Sapienza University, P.le Aldo Moro 2, 00185, Rome (Italy)

2011-03-11T23:59:59.000Z

17

Transverse pulse shaping and optimization of a tapered hard X-ray free electron laser  

E-Print Network [OSTI]

Multidimensional optimization schemes for TW hard X-Ray free electron lasers are applied to the cases of transversely uniform and parabolic electron beam distributions and compared to examples of transversely Gaussian beams. The optimizations are performed for a $200$m undulator and a resonant wavelength of $\\lambda_r=1.5\\AA $ using the fully 3-dimensional FEL particle code GENESIS. Time dependent simulations showed that the maximum radiation power is larger for flatter transverse distributions due to enhanced optical guiding in the tapered section of the undulator. For a transversely Gaussian beam the maximum output power was found to be $\\text{P}_{max}$=$1.56$ TW compared to $2.26$ TW for the parabolic case and $2.63$ TW for the uniform case. Spectral data also showed a 30-70$\\%$ reduction in energy deposited in the sidebands for the uniform and parabolic beams compared with a Gaussian. An analysis of the maximum power as a function of detuning from resonance shows that redshifting the central wavelength by...

Emma, Claudio; Wu, Juhao

2014-01-01T23:59:59.000Z

18

Projected performance of rf-linac-driven free-electron lasers in the VUV and soft x-ray regions  

SciTech Connect (OSTI)

A multidisciplinary team of Los Alamos scientists, supported by the US Department of Energy, has been developing the requisite technologies to extend free-electron laser (FEL) operation from infrared and visible wavelengths into the extreme-ultraviolet below 100 nm using rf-linear accelerator technology. The goal is to establish an XUV Free-Electron Laser User Facility, the next-generation light source that will make available to researchers optical power more than one-million times greater than provided by synchroton light sources. Based primarily on a series of FEL oscillators driven by a single, rf-linac, the Los Alamos facility is designed to generate broadly tunable, picosecond-pulse, coherent radiation spanning the soft x-ray through the ultraviolet to the visible spectral ranges from 1 nm to 400 nm. The FEL facility design is discussed and performance predicted. 3 figs., 5 tabs.

Newnam, B.E.

1987-12-01T23:59:59.000Z

19

SciTech Connect: Compact X-ray Free Electron Laser from a Laser...  

Office of Scientific and Technical Information (OSTI)

Gradient Undulator Compact laser-plasma accelerators can produce high energy electron beams with low emittance, high peak current but a rather large energy spread. The large...

20

R&D for a Soft X-Ray Free Electron Laser Facility  

E-Print Network [OSTI]

x-ray magnetic linear dichroism spectromicroscop,y” Scienceultrafast magnetic phenomena and materials science [44].Magnet Science & Technology, National High Magnetic Field

Staples, John

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "x-ray free-electron laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Using X-ray free-electron lasers for probing of complex interaction dynamics of ultra-intense lasers with solid matter  

SciTech Connect (OSTI)

We demonstrate the potential of X-ray free-electron lasers (XFEL) to advance the understanding of complex plasma dynamics by allowing for the first time nanometer and femtosecond resolution at the same time in plasma diagnostics. Plasma phenomena on such short timescales are of high relevance for many fields of physics, in particular in the ultra-intense ultra-short laser interaction with matter. Highly relevant yet only partially understood phenomena become directly accessible in experiment. These include relativistic laser absorption at solid targets, creation of energetic electrons and electron transport in warm dense matter, including the seeding and development of surface and beam instabilities, ambipolar expansion, shock formation, and dynamics at the surfaces or at buried layers. In this paper, we focus on XFEL plasma probing for high power laser matter interactions based on quantitative calculations using synthesized data and evaluate the feasibility of various imaging and scattering techniques with special focus on the small angle X-ray scattering technique.

Kluge, T., E-mail: t.kluge@hzdr.de; Huang, L. G.; Metzkes, J.; Bussmann, M. [Helmholtz-Zentrum Dresden-Rossendorf e.V., D-01328 Dresden (Germany)] [Helmholtz-Zentrum Dresden-Rossendorf e.V., D-01328 Dresden (Germany); Gutt, C. [Universität Siegen, D-57068 Siegen (Germany)] [Universität Siegen, D-57068 Siegen (Germany); Schramm, U.; Cowan, T. E. [Helmholtz-Zentrum Dresden-Rossendorf e.V., D-01328 Dresden (Germany) [Helmholtz-Zentrum Dresden-Rossendorf e.V., D-01328 Dresden (Germany); Technische Universität Dresden, D-01062 Dresden (Germany)

2014-03-15T23:59:59.000Z

22

Study of the Feasibility of an X-Ray Free Electron Laser with a 15 GeV CLIC Beam  

E-Print Network [OSTI]

This note presents a study of the feasibility of a Free Electron Laser (FEL) using an electron beam from the Compact Linear Collider (CLIC). We first show that, with the nominal CLIC layout, the energy spread at 15 GeV would be too large to allow FEL saturation in an undulator of reasonable length. An alternative scheme was studied, with a dedicated source, with a by-pass of the damping rings and with magnetic compression between the various acceleration stages. With this scheme, the energy spread of the CLIC beam can be reduced from 1.5% to 0.1%, but the emittance is much larger and, although the power gain is better than in the nominal case, FEL saturation is still not reached. We show that the energy spread or the transverse emittance would have to be reduced by another order of magnitude in order to obtain FEL saturation.

Brandin, M; Ekelöf, T J C; Ferrari, A

2002-01-01T23:59:59.000Z

23

Methods development for diffraction and spectroscopy studies of metalloenzymes at X-ray free-electron lasers  

Science Journals Connector (OSTI)

...on electrofocusing, an energy dispersive von Hamos X-ray...spectroscopy data collected by us at the Linac Coherent...deposition of radiation energy by the X-ray pulse was...we review the current status of methods developed in...packages developed by us to process both spectroscopic...

2014-01-01T23:59:59.000Z

24

Methods development for diffraction and spectroscopy studies of metalloenzymes at X-ray free-electron lasers  

Science Journals Connector (OSTI)

...Coherent Light Source, taking...Coherent Light Source (LCLS...radiation energy by the X-ray...developed by us to process...large sample consumption is not sustainable...Coherent Light Source (LCLS...operated for the US Department of Energy Office of...

2014-01-01T23:59:59.000Z

25

Multiphoton above-threshold ionization in superintense free-electron x-ray laser fields: Beyond the dipole approximation  

E-Print Network [OSTI]

(k,k?,t)Yl?m?(? ?,??)d#12;d#12;? (17) and Blm,l?m? (k,k?,t) = kk? ? ? Y ?lm(?,?)B(k,k?,t)Yl?m?(? ?,??)d#12;d#12;?, (18) respectively. For the laser pulse given by Eq. (2), Dlm,l?m?(k,k?,t) and Blm,l?m? (k,k?,t) are calculated using Eqs. (B1) and (B2) in Appendix B...†(k?,k,t) = D(k,k?,t) and B†(k?,k,t) = B(k,k?,t). Thus the P-space Hamiltonian given by Eq. (7), H (k,k?,t), is Hermitian. APPENDIX B: P-SPACE PARTIAL-WAVE LASER-ELECTRON INTERACTIONS Substituting Eqs. (A1) and (A2) into Eqs. (17) and (18), respectively, we...

Zhou, Zhongyuan; Chu, Shih-I

2013-02-13T23:59:59.000Z

26

X-ray laser  

DOE Patents [OSTI]

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.

Nilsen, Joseph (Livermore, CA)

1991-01-01T23:59:59.000Z

27

Free electron laser  

DOE Patents [OSTI]

A high gain, single-pass free electron laser formed of a high brilliance electron injector source, a linear accelerator which imparts high energy to the electron beam, and an undulator capable of extremely high magnetic fields, yet with a very short period. The electron injector source is the first stage (gap) of the linear accelerator or a radial line transformer driven by fast circular switch. The linear accelerator is formed of a plurality of accelerating gaps arranged in series. These gaps are energized in sequence by releasing a single pulse of energy which propagates simultaneously along a plurality of transmission lines, each of which feeds the gaps. The transmission lines are graduated in length so that pulse power is present at each gap as the accelerated electrons pass therethrough. The transmission lines for each gap are open circuited at their ends. The undualtor has a structure similar to the accelerator, except that the transmission lines for each gap are substantially short circuited at their ends, thus converting the electric field into magnetic field. A small amount of resistance is retained in order to generate a small electric field for replenishing the electron bunch with the energy lost as it traverses through the undulator structure.

Villa, Francesco (Alameda, CA)

1990-01-01T23:59:59.000Z

28

Circular free-electron laser  

DOE Patents [OSTI]

A high efficiency, free electron laser utilizing a circular relativistic electron beam accelerator and a circular whispering mode optical waveguide for guiding optical energy in a circular path in the circular relativistic electron beam accelerator such that the circular relativistic electron beam and the optical energy are spatially contiguous in a resonant condition for free electron laser operation. Both a betatron and synchrotron are disclosed for use in the present invention. A free electron laser wiggler is disposed around the circular relativistic electron beam accelerator for generating a periodic magnetic field to transform energy from the circular relativistic electron beam to optical energy.

Brau, Charles A. (Los Alamos, NM); Kurnit, Norman A. (Santa Fe, NM); Cooper, Richard K. (Los Alamos, NM)

1984-01-01T23:59:59.000Z

29

Rf Feedback free electron laser  

DOE Patents [OSTI]

A free electron laser system and electron beam system for a free electron laser which use rf feedback to enhance efficiency. Rf energy is extracted from an electron beam by decelerating cavities and returned to accelerating cavities using rf returns such as rf waveguides, rf feedthroughs, etc. This rf energy is added to rf klystron energy to lower the required input energy and thereby enhance energy efficiency of the system.

Brau, Charles A. (Los Alamos, NM); Swenson, Donald A. (Los Alamos, NM); Boyd, Jr., Thomas J. (Los Alamos, NM)

1981-01-01T23:59:59.000Z

30

Progress toward the Wisconsin Free Electron Laser  

SciTech Connect (OSTI)

The University of Wisconsin-Madison/Synchrotron Radiation Center is advancing its design for a seeded VUV/soft X-ray Free Electron Laser facility called WiFEL. To support this vision of an ultimate light source, we are pursuing a program of strategic R&D addressing several crucial elements. This includes development of a high repetition rate, VHF superconducting RF electron gun, R&D on photocathode materials by ARPES studies, and evaluation of FEL facility architectures (e.g., recirculation, compressor scenarios, CSR dechirping, undulator technologies) with the specific goal of cost containment. Studies of high harmonic generation for laser seeding are also planned.

Bisognano, Joseph; Eisert, D; Fisher, M V; Green, M A; Jacobs, K; Kleman, K J; Kulpin, J; Rogers, G C; Lawler, J E; Yavuz, D

2011-03-01T23:59:59.000Z

31

Injection of harmonics generated in gas in a free-electron laser providing intense and  

E-Print Network [OSTI]

-ultraviolet to X-ray region. Recently, injection of a single-pass FEL by the third laser harmonic of a TiLETTERS Injection of harmonics generated in gas in a free-electron laser providing intense-electron lasers promise to extend this down to femtosecond timescales. The process by which free-electron lasers

Loss, Daniel

32

Optics for X-Ray Laser and Laser Plasma Soft X-Ray Radiation  

Science Journals Connector (OSTI)

Focusing X-ray grazing incidence optics for X-ray laser and laser plasma soft X-ray radiation has been studied. ... computer code. Parabolic axisymmetric mirror for focusing Princeton X-ray laser beam and ellipso...

L. Pina; A. Inneman; R. Hudec

1996-01-01T23:59:59.000Z

33

Free-Electron Laser Targets Fat | Jefferson Lab  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Free-Electron Laser Targets Fat April 10, 2006 Free-Electron Laser Scientists Rox Anderson, right, and Free-Electron Laser Scientist Steve Benson, left, discuss laser beam...

34

Combination free electron and gaseous laser  

DOE Patents [OSTI]

A multiple laser having one or more gaseous laser stages and one or more free electron stages. Each of the free electron laser stages is sequentially pumped by a microwave linear accelerator. Subsequently, the electron beam is directed through a gaseous laser, in the preferred embodiment, and in an alternative embodiment, through a microwave accelerator to lower the energy level of the electron beam to pump one or more gaseous lasers. The combination laser provides high pulse repetition frequencies, on the order of 1 kHz or greater, high power capability, high efficiency, and tunability in the synchronous production of multiple beams of coherent optical radiation.

Brau, Charles A. (Los Alamos, NM); Rockwood, Stephen D. (Los Alamos, NM); Stein, William E. (Los Alamos, NM)

1980-01-01T23:59:59.000Z

35

Free-Electron Laser | Jefferson Lab  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Research Inspecting an injector assembly at Jefferson Lab's Free-Electron Laser. A D D I T I O N A L L I N K S: FEL Users FEL Description JLAMP Proposal Applications FEL News...

36

Inverse free electron laser accelerator for advanced light sources  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

We discuss the inverse free electron laser (IFEL) scheme as a compact high gradient accelerator solution for driving advanced light sources such as a soft x-ray free electron laser amplifier or an inverse Compton scattering based gamma-ray source. In particular, we present a series of new developments aimed at improving the design of future IFEL accelerators. These include a new procedure to optimize the choice of the undulator tapering, a new concept for prebunching which greatly improves the fraction of trapped particles and the final energy spread, and a self-consistent study of beam loading effects which leads to an energy-efficient high laser-to-beam power conversion.

Duris, J. P.; Musumeci, P.; Li, R. K.

2012-06-01T23:59:59.000Z

37

Applications of soft x-ray lasers  

SciTech Connect (OSTI)

The high brightness and short pulse duration of soft x-ray lasers provide unique advantages for novel applications. Imaging of biological specimens using x-ray lasers has been demonstrated by several groups. Other applications to fields such as chemistry, material science, plasma diagnostics, and lithography are beginning to emerge. We review the current status of soft x-ray lasers from the perspective of applications, and present an overview of the applications currently being developed.

Skinner, C.H.

1993-08-01T23:59:59.000Z

38

X-Ray Laser Sources for Microscopy  

Science Journals Connector (OSTI)

Progress and prospects in soft X-ray laser development at Princeton are presented. A comparison to plasma and synchrotron sources is made with a...

C. H. Skinner; D. E. Kim; A. Wouters; D. Voorhees; S. Suckewer

1988-01-01T23:59:59.000Z

39

Optical wavelength modulation in free electron lasers  

SciTech Connect (OSTI)

An attribute of the free electron laser (FEL) is the continuous tunability of the optical wavelength by modulation of the electron beam energy. The variation of the wavelength and power of the optical beam is studied as a function of FEL operating parameters. These results will be applied to the Stanford SCA FEL and Boeing FEL.

Mabe, R.M.; Wong, R.K.; Colson, W.B. [Naval Postgraduate School, Monterey, CA (United States)

1995-12-31T23:59:59.000Z

40

Ultrafast X-ray Absorption Spectroscopy using Laser-Driven Electron X-ray Sources (LEXS)  

E-Print Network [OSTI]

: ultrafast x-rays, x-ray absorption spectroscopy, terawatt lasers, ultrafast reaction dynamics, atomic motion atomic motion by scrutinizing the changes in x- ray absorption spectra during reactions. FirstUltrafast X-ray Absorption Spectroscopy using Laser-Driven Electron X-ray Sources (LEXS) Guangjun

Guo, Ting

Note: This page contains sample records for the topic "x-ray free-electron laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

X-ray laser microscope apparatus  

DOE Patents [OSTI]

A microscope consisting of an x-ray contact microscope and an optical microscope. The optical, phase contrast, microscope is used to align a target with respect to a source of soft x-rays. The source of soft x-rays preferably comprises an x-ray laser but could comprise a synchrotron or other pulse source of x-rays. Transparent resist material is used to support the target. The optical microscope is located on the opposite side of the transparent resist material from the target and is employed to align the target with respect to the anticipated soft x-ray laser beam. After alignment with the use of the optical microscope, the target is exposed to the soft x-ray laser beam. The x-ray sensitive transparent resist material whose chemical bonds are altered by the x-ray beam passing through the target mater GOVERNMENT LICENSE RIGHTS This invention was made with government support under Contract No. De-FG02-86ER13609 awarded by the Department of Energy. The Government has certain rights in this invention.

Suckewer, Szymon (Princeton, NJ); DiCicco, Darrell S. (Plainsboro, NJ); Hirschberg, Joseph G. (Coral Gables, FL); Meixler, Lewis D. (East Windsor, NJ); Sathre, Robert (Princeton, NJ); Skinner, Charles H. (Lawrenceville, NJ)

1990-01-01T23:59:59.000Z

42

Lensless X-Ray Imaging in Reflection  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Lensless X-Ray Imaging in Reflection Lensless X-Ray Imaging in Reflection Print Wednesday, 26 October 2011 00:00 The advent of x-ray free-electron laser (XFEL) light sources has...

43

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

SciTech Connect (OSTI)

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

Kato, M.; Tanaka, T.; Saito, N. [National Institute of Advanced Industrial Science and Technology (AIST), NMIJ, Tsukuba 305-8568 (Japan); RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Kurosawa, T. [National Institute of Advanced Industrial Science and Technology (AIST), NMIJ, Tsukuba 305-8568 (Japan); Richter, M. [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Physikalisch-Technische Bundesanstalt (PTB), Abbestrasse 2-12, D-10587 Berlin (Germany); Sorokin, A. A. [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Deutsches Elektronen-Synchrotron (DESY), Notkestrasse 85, D-22603 Hamburg (Germany); Ioffe Physico-Technical Institute, RAS, Polytekhnicheskaya 26, 194021 St. Petersburg (Russian Federation); Tiedtke, K. [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Deutsches Elektronen-Synchrotron (DESY), Notkestrasse 85, D-22603 Hamburg (Germany); Kudo, T.; Yabashi, M. [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Tono, K. [Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Ishikawa, T. [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan)

2012-07-09T23:59:59.000Z

44

following an electron bunch for free electron laser  

SciTech Connect (OSTI)

A video artist's ultra-slow-motion impression of an APEX-style electron gun firing a continuous train of electron bunches into a superconducting linear accelerator (in reality this would happen a million times a second). As they approach the speed of light the bunches contract, maintaining beam quality. After acceleration, the electron bunches are diverted into one or more undulators, the key components of free electron lasers. Oscillating back and forth in the changing magnetic field, they create beams of structured x-ray pulses. Before entering the experimental areas the electron bunches are diverted to a beam dump. (Animation created by Illumina Visual, http://www.illuminavisual.com/, for Lawrence Berkeley National Laboratory. Music for this excerpt, "Feeling Dark (Behind The Mask)" is by 7OOP3D http://ccmixter.org/files/7OOP3D/29126 and is licensed under a Creative Commons license: http://creativecommons.org/licenses/by-nc/3.0/)

None

2012-01-01T23:59:59.000Z

45

Development of x-ray photoelectron microscope with an x-ray laser source  

Science Journals Connector (OSTI)

We have constructed an x-ray photoelectron microscopic system with an x-ray laser as an x-ray source. The lasing line is the Li-like Al 3d-4f transition at 15.47 nm where the recombining Al plasma is used as the x-ray laser medium. The beam from the x-ray laser cavity was then focused by using a Schwarzschild mirror coated with Mo/Si multilayers. The x-ray beam size with a diameter less than 0.5 ?m and the estimated photon number of about 2×10 6 ? photons/shot into the spot were achieved.

Tadayuki Ohchi; Naohiro Yamaguchi; Chiemi Fujikawa; Tamio Hara; Katsumi Watanabe; Ibuki Tanaka; Masami Taguchi

2000-01-01T23:59:59.000Z

46

Rippled beam free electron laser amplifier  

DOE Patents [OSTI]

A free electron laser amplifier provides a scalloping annular electron beam that interacts with the axial electric field of a TM.sub.0n mode. A waveguide defines an axial centerline and, a solenoid arranged about the waveguide produces an axial constant magnetic field within the waveguide. An electron beam source outputs a annular electron beam that interacts with the axial magnetic field to have an equilibrium radius and a ripple radius component having a variable radius with a ripple period along the axial centerline. An rf source outputs an axial electric field that propagates within the waveguide coaxial with the electron beam and has a radial mode that interacts at the electron beam at the equilibrium radius component of the electron beam.

Carlsten, Bruce E. (Los Alamos, NM)

1999-01-01T23:59:59.000Z

47

Jefferson Lab's upgraded Free-Electron Laser produces first ligh...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

upgraded Free-Electron Laser produces first light June 18, 2003 Researchers at the U.S. Department of Energy's Thomas Jefferson National Accelerator Facility have produced first...

48

Free-Electron Lasers: Present Status and Future Prospects  

E-Print Network [OSTI]

US Department of Energy under contract DE-AC03-76SF00098. LBL-29124 Free-Electron Lasers: Present Status

Kim, K.-J.

2008-01-01T23:59:59.000Z

49

X-ray laser frequency near-doubling and generation of tunable coherent x rays in plasma  

E-Print Network [OSTI]

X-ray laser frequency near-doubling and generation of tunable coherent x rays in plasma P. L plasmas in which efficient x-ray laser frequency near-doubling is expected for a number of available x-ray of coherent x rays and tunable optical radiation may result in tunable coherent x-ray radiation powerful

Kaplan, Alexander

50

Soft x-ray laser microscope  

SciTech Connect (OSTI)

The program consisted of two phases (Phase I and Phase II). The goal of the Phase I (first year program) was to design and construct the Soft X-ray Laser Contact Microscope. Such microscope was constructed and adapted to PPL's 18.2nm soft X-ray Laser (SXL), which in turn was modified and prepared for microscopy experiments. Investigation of the photoresist response to 18.2nm laser radiation and transmissivity of 0.1m thick silicion-nitride (Si[sub 3]N[sub 4]) windows were important initial works. The goal of the first year of Phase II was to construct X-ray contact microscope in combination with existing optical phase microscope, already used by biologists. In the second year of Phase II study of dehydrated Horeseshoe Crab and Hela cancer cells were performed with COXRALM. Also during Phase II, the Imaging X-Ray Laser Microscope (IXRALM) was designed and constructed. This paper describes the development of each of the microscopes and their application for research.

Suckewer, P.I.

1990-10-01T23:59:59.000Z

51

X-ray laser system, x-ray laser and method  

DOE Patents [OSTI]

Disclosed is an x-ray laser system comprising a laser containing generating means for emitting short wave length radiation, and means external to said laser for energizing said generating means, wherein when the laser is in an operative mode emitting radiation, the radiation has a transverse coherence length to width ratio of from about 0.05 to 1. Also disclosed is a method of adjusting the parameters of the laser to achieve the desired coherence length to laser width ratio.

London, Richard A. (Oakland, CA); Rosen, Mordecai D. (Berkeley, CA); Strauss, Moshe (Omer, IL)

1992-01-01T23:59:59.000Z

52

Ignition feedback regenerative free electron laser (FEL) amplifier  

DOE Patents [OSTI]

An ignition feedback regenerative amplifier consists of an injector, a linear accelerator with energy recovery, and a high-gain free electron laser amplifier. A fraction of the free electron laser output is coupled to the input to operate the free electron laser in the regenerative mode. A mode filter in this loop prevents run away instability. Another fraction of the output, after suitable frequency up conversion, is used to drive the photocathode. An external laser is provided to start up both the amplifier and the injector, thus igniting the system.

Kim, Kwang-Je (Burr Ridge, IL); Zholents, Alexander (Walnut Creek, CA); Zolotorev, Max (Oakland, CA)

2001-01-01T23:59:59.000Z

53

Simulations of the rocketdyne free-electron laser  

SciTech Connect (OSTI)

Rocketdyne is assembling a high-brightness 78 MeV free-electron laser (FEL). In this paper performance calculations using the Rocketdyne FELOPT code are presented for a 1.06 {mu}m system.

Cover, R.A.; Bennett, G.T.; Burke, R.J.; Curtin, M.S.; Lampel, M.C.; Rakowsky, G. (Rockwell International Corp., Canoga Park, CA (United States). Rocketdyne Div.)

1991-12-01T23:59:59.000Z

54

Lensless X-Ray Imaging in Reflection  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

X-Ray Imaging in Reflection Print The advent of x-ray free-electron laser (XFEL) light sources has led to an outburst of research activities in the field of lensless imaging. XFELs...

55

Lensless X-Ray Imaging in Reflection  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

X-Ray Imaging in Reflection Print Wednesday, 26 October 2011 00:00 The advent of x-ray free-electron laser (XFEL) light sources has led to an outburst of research activities...

56

Single electron beam rf feedback free electron laser  

DOE Patents [OSTI]

A free electron laser system and electron beam system for a free electron laser which uses rf feedback to enhance efficiency are described. Rf energy is extracted from a single electron beam by decelerating cavities and energy is returned to accelerating cavities using rf returns, such as rf waveguides, rf feedthroughs, resonant feedthroughs, etc. This rf energy is added to rf klystron energy to reduce the required input energy and thereby enhance energy efficiency of the system.

Brau, C.A.; Stein, W.E.; Rockwood, S.D.

1981-02-11T23:59:59.000Z

57

Two-dimensional optimization of free-electron-laser designs  

DOE Patents [OSTI]

Off-axis, two-dimensional designs for free electron lasers are described that maintain correspondence of a light beam with a synchronous electron at an optimal transverse radius r > 0 to achieve increased beam trapping efficiency and enhanced laser beam wavefront control so as to decrease optical beam diffraction and other deleterious effects.

Prosnitz, D.; Haas, R.A.

1982-05-04T23:59:59.000Z

58

Two-dimensional optimization of free electron laser designs  

DOE Patents [OSTI]

Off-axis, two-dimensional designs for free electron lasers that maintain correspondence of a light beam with a "synchronous electron" at an optimal transverse radius r>0 to achieve increased beam trapping efficiency and enhanced laser beam wavefront control so as to decrease optical beam diffraction and other deleterious effects.

Prosnitz, Donald (Walnut Creek, CA); Haas, Roger A. (Pleasanton, CA)

1985-01-01T23:59:59.000Z

59

Nonlinear optics with focused x-ray lasers  

SciTech Connect (OSTI)

We have investigated the possibility of focusing x-ray lasers with the use of multilayered mirrors or zone plates. The results indicate that x-ray intensities as high as 10{sup 14} W/cm{sup 2} can be achieved by focusing saturated Ne-like x-ray lasers. These intensities should be adequate for studying nonlinear optical phenomena. 9 refs., 2 figs.

DaSilva, L.B.; Muendel, M.H.; Falcone, R.W.; Fields, D.J.; Kortright, J.B.; MacGowan, B.J.; Matthews, D.L.; Mrowka, S.; Shimkaveg, G.M.; Trebes, J.E.

1990-12-12T23:59:59.000Z

60

Laser Copper Plasma X-ray Source Debris Characterization  

E-Print Network [OSTI]

Laser Copper Plasma X-ray Source Debris Characterization A Thesis Presented by David Hurley 3, 2007 Vice President for Research and Dean of Graduate studies #12;Abstract Laser copper plasma for x-ray lithography. Copper debris in the form of vapor, ions, dust, and high-speed particles

Huston, Dryver R.

Note: This page contains sample records for the topic "x-ray free-electron laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Free electron laser amplifier driven by an induction linac  

SciTech Connect (OSTI)

This paper discusses the use of a free-electron laser amplifier as a means of converting the kinetic energy of an electron beam into coherent radiation. In particular, the use of an induction linear accelerator is discussed. The motion of the elections in the tapered and untapered wiggler magnets is discussed as well as the beam emittance, and the radiation fields involved. (LSP)

Neil, V.K.

1986-06-03T23:59:59.000Z

62

Wiggler plane focusing in a linear free electron laser  

DOE Patents [OSTI]

This disclosure describes a free electron laser apparatus that provides a magnetic centering force to turn or focus a non-axial electron toward the longitudinal axis as desired. The focusing effect is provided by wiggler magnet pole faces that are approximately parabolically shaped.

Scharlemann, E.T.

1985-11-21T23:59:59.000Z

63

Formation of microbeam using tabletop soft X-ray laser  

Science Journals Connector (OSTI)

An X-ray microprobe with a sub-micron size beam and high intensity can provide X-ray analyses with a remarkable spatial resolution. We have performed focusing of an X-ray laser output into a sub-micron beam for the first time. In our experiment, an X-ray laser of Li-like Al 3d–4f transition at 15.47 nm was delivered from an unstable cavity consisting of a concave mirror and a flat mirror with a square orifice of 100×100 ?m in size. The beam from the orifice was then focused by using a Schwarzschild mirror coated with a Mo/Si multilayer. An X-ray beam size with a diameter of about 0.45 ?m and an estimated photon number of about 2×106 photons per shot was achieved. Such sources could be well suited for the realization of X-ray microprobes.

Tadayuki Ohchi; Naohiro Yamaguchi; Chiemi Fujikawa; Tamio Hara

1999-01-01T23:59:59.000Z

64

A Proof-of-Principle Echo-enabled Harmonic Generation Free Electron Laser Experiment at SLAC  

SciTech Connect (OSTI)

With the advent of X-ray Free Electron Lasers (FELs), new methods have been developed to extend capabilities at short wavelengths beyond Self-Amplified Spontaneous Emission (SASE). In particular, seeding of a FEL allows for temporal control of the radiation pulse and increases the peak brightness by orders of magnitude. Most recently, Gennady Stupakov and colleagues at SLAC proposed a new technique: Echo-Enabled Harmonic Generation (EEHG). Here a laser microbunches the beam in an undulator and the beam is sheared in a chicane. This process is repeated with a second laser, undulator and chicane. The interplay between these allows a seeding of the X-ray laser up to the 100th harmonic of the first laser. After introducing the physics of FELs and the EEHG seeding technique, we describe contributions to the experimental effort. We will present detailed studies of the experiment including the choice of parameters and their optimization, the emittance effect, spontaneous emission in the undulators, the second laser phase effect, and measurements of the jitter between RF stations. Finally, the status and preliminary results of the Echo-7 experiment will be outlined.

Pernet, Pierre-Louis; /Ecole Polytechnique, Lausanne /SLAC

2012-01-06T23:59:59.000Z

65

Chirped pulse inverse free-electron laser vacuum accelerator  

DOE Patents [OSTI]

A chirped pulse inverse free-electron laser (IFEL) vacuum accelerator for high gradient laser acceleration in vacuum. By the use of an ultrashort (femtosecond), ultrahigh intensity chirped laser pulse both the IFEL interaction bandwidth and accelerating gradient are increased, thus yielding large gains in a compact system. In addition, the IFEL resonance condition can be maintained throughout the interaction region by using a chirped drive laser wave. In addition, diffraction can be alleviated by taking advantage of the laser optical bandwidth with negative dispersion focusing optics to produce a chromatic line focus. The combination of these features results in a compact, efficient vacuum laser accelerator which finds many applications including high energy physics, compact table-top laser accelerator for medical imaging and therapy, material science, and basic physics.

Hartemann, Frederic V. (Dublin, CA); Baldis, Hector A. (Pleasanton, CA); Landahl, Eric C. (Walnut Creek, CA)

2002-01-01T23:59:59.000Z

66

First operation of the Rocketdyne/Stanford free electron laser  

Science Journals Connector (OSTI)

A near infrared free electron laser (FEL) has been built and installed by Rocketdyne in the Stanford Photon Research Laboratory. The Rocketdyne/Stanford FEL utilizes a very high quality, 2 m long, permanent magnet planar wiggler whose gap may be continuously tuned, and magnetic field axially tapered by varying the gap at one end relative to the other. The laser is operated with an e-beam supplied by the Stanford Mark-III accelerator. A stable resonator with a broadband, dielectric coated element permits transmissive outcoupling over the 2.7–3.7 ?m wavelength range. Results from initial operation of this laser are presented.

Anup Bhowmik; Mark S. Curtin; Wayne A. McMullin; Stephen V. Benson; John M.J. Madey; Bruce A. Richman; Louis Vintro

1988-01-01T23:59:59.000Z

67

E-Print Network 3.0 - alamos free-electron laser Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

free-electron laser Search Powered by Explorit Topic List Advanced Search Sample search results for: alamos free-electron laser Page: << < 1 2 3 4 5 > >> 1 Applications: Medical...

68

E-Print Network 3.0 - axial free-electron laser Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

free-electron laser Search Powered by Explorit Topic List Advanced Search Sample search results for: axial free-electron laser Page: << < 1 2 3 4 5 > >> 1 JOURNAL DE PHYSIQUE...

69

George Neil Named to Lead JLab's Free-Electron Laser Program...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

George Neil Named to Lead JLab's Free-Electron Laser Program NEWPORT NEWS, Va., Feb.15, 2008 - Dr. George Neil has been named Associate Director of the Free-Electron Laser Division...

70

Free-electron laser scientist is one of two newly elected American...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Steve Benson Steve Benson of the Free-Electron Laser (FEL) group was recently selected as a 2002 Fellow of the American Physical Society Free-electron laser scientist is one of two...

71

In the OSTI Collections: Free-Electron Lasers | OSTI, US Dept of Energy,  

Office of Scientific and Technical Information (OSTI)

Free-Electron Lasers Free-Electron Lasers Existing Free-Electron Lasers Using Free-Electron Lasers for Measurement and Defense New Free-Electron Laser Designs References Research Organizations Reports available from OSTI's Information Bridge While most types of laser produce coherent light from electric charges bound within atoms, molecules, or solids, unbound charges are the light source in free-electron lasers. Lasers of this type can operate at higher frequencies than are easily achieved with bound-electron lasers. Various uses and designs of free-electron lasers are the focus of different projects sponsored through the Department of Energy. Lasers, like any source of light or other electromagnetic waves, produce waves when some of the electric charges they contain go from having a

72

Hard x-ray or gamma ray laser by a dense electron beam  

E-Print Network [OSTI]

A coherent x-ray or gamma ray can be created from a dense electron beam propagating through an intense laser undulator. It is analyzed by using the Landau damping theory which suits better than the conventional linear analysis for the free electron laser, as the electron beam energy spread is high. The analysis suggests that the currently available physical parameters would enable the generation of the coherent gamma ray of up to 100 keV. The electron quantum diffraction suppresses the FEL action, by which the maximum radiation energy to be generated is limited.

S. Son; S. J. Moon

2012-02-12T23:59:59.000Z

73

Compact two-beam push-pull free electron laser  

DOE Patents [OSTI]

An ultra-compact free electron laser comprising a pair of opposed superconducting cavities that produce identical electron beams moving in opposite directions such that each set of superconducting cavities accelerates one electron beam and decelerates the other electron beam. Such an arrangement, allows the energy used to accelerate one beam to be recovered and used again to accelerate the second beam, thus, each electron beam is decelerated by a different structure than that which accelerated it so that energy exchange rather than recovery is achieved resulting in a more compact and highly efficient apparatus.

Hutton, Andrew (Yorktown, VA)

2009-03-03T23:59:59.000Z

74

Vanadium-pumped titanium x-ray laser  

DOE Patents [OSTI]

A resonantly photo-pumped x-ray laser is formed of a vanadium and titanium foil combination that is driven by two beams of intense line focused optical laser radiation. Ground state neon-like titanium ions are resonantly photo-pumped by line emission from fluorine-like vanadium ions. 4 figs.

Nilsen, J.

1992-05-26T23:59:59.000Z

75

Vanadium-pumped titanium x-ray laser  

DOE Patents [OSTI]

A resonantly photo-pumped x-ray laser (10) is formed of a vanadium (12) and titanium (14) foil combination (16) that is driven by two beams (18, 20) of intense line focused (22, 24) optical laser radiation. Ground state neon-like titanium ions (34) are resonantly photo-pumped by line emission from fluorine-like vanadium ions (32).

Nilsen, Joseph (Livermore, CA)

1992-01-01T23:59:59.000Z

76

DOE Science Showcase - Free-Electron Lasers | OSTI, US Dept of Energy,  

Office of Scientific and Technical Information (OSTI)

Free-Electron Lasers Free-Electron Lasers Free-Electron Lasers absorb and release energy at any wavelength and can be controlled more precisely than conventional lasers by producing intense powerful light in brief bursts with extreme precision. This innovative technology has opened doors to a vast array of possibilities for manufacturing and for basic research. Read more in the white paper In OSTI Collections: Free-Electron Lasers by Dr. William Watson, Physicist, OSTI staff. Free-Electron Lasers Results in DOE Databases Science.gov Ciencia.Science.gov (Español) WorldWideScience.org Energy Citations Database DOE Information Bridge Relevant Subject Clusters FREE ELECTRON LASERS PARTICLE ACCELERATORS ENGINEERING LASERS ELECTRON BEAMS ACCELERATORS WIGGLER MAGNETS EQUIPMENT ELECTROMAGNETIC RADIATION

77

fel 2005 :: Free Electron Laser Conference and Workshop  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Home | Attendee List | Program | Abstract Submission | Payment | Call for Papers | Exhibitors | Travel 2005 International Free Electron Laser Prize Winner: Avi Gover left to right: John Galayda, Avi Gover (FEL2005 Prize Winner, Alexander Van der Meer This year the FEL Prize Committee awarded the FEL Prize to Avraham (Avi) Gover from Tel-Aviv University for his pioneering work in laying the foundation of FEL theory. Avi Gover, presently head of the FEL Knowledge Center in Israel, has been a member of the FEL community from the very beginning, publishing his first paper on FELs in 1976. In those early years, he played a key role in putting FEL theory on a firm basis by showing the similarities between FELs, 'ordinary' lasers and other free electron radiation devices such as TWTs. In later years he made important contributions to the formulation of a unified theory of superradiant emission in the linear and, more recently, also in the non-linear regime. His deep understanding of the field enabled him to propose conceptually new schemes like stimulated superradiance and post-saturation emission enhancement. In addition to his extensive work and contributions to FEL theory, he also led and contributed to a number of experimental projects aimed at studies of fundamental effects and at the development of new FEL device schemes. Most notably the demonstration of a two-stage BWO FEL and a longitudinal wiggler FEL, demonstration of electron trapping in two counter propagating laser beams and of single-mode locking in a prebunched FEM. He has also been the main driving force behind the international efforts to develop high-average power masers based on electrostatic accelerators in the inverted setup, that is with the undulator at high voltage. Along this line, he also took the initiative for an Israelean FEM user facility and notwithstanding the difficult funding situation in his country, this facility is now operational at the College of Judea and Samaria in Ariel.

78

XUV free-electron laser-based projection lithography systems  

SciTech Connect (OSTI)

Free-electron laser sources, driven by rf-linear accelerators, have the potential to operate in the extreme ultraviolet (XUV) spectral range with more than sufficient average power for high-volume projection lithography. For XUV wavelengths from 100 nm to 4 nm, such sources will enable the resolution limit of optical projection lithography to be extended from 0.25 {mu}m to 0.05{mu}m and with an adequate total depth of focus (1 to 2 {mu}m). Recent developments of a photoinjector of very bright electron beams, high-precision magnetic undulators, and ring-resonator cavities raise our confidence that FEL operation below 100 nm is ready for prototype demonstration. We address the motivation for an XUV FEL source for commercial microcircuit production and its integration into a lithographic system, include reflecting reduction masks, reflecting XUV projection optics and alignment systems, and surface-imaging photoresists. 52 refs., 7 figs.

Newnam, B.E.

1990-01-01T23:59:59.000Z

79

Improving electron beam quality of the Boeing free electron laser  

Science Journals Connector (OSTI)

The successful operation of any free electron laser (FEL) is critically dependent upon electron beam quality. In a radiofrequency (rf) accelerator the micropulse or instantaneous beam emittance and peak current is established by the injector, however, it is important to maintain this beam's quality as it is accelerated and transported to the wiggler. In the past year, work has continued to enhance the electron beam of the Boeing FEL. The previous year's improvements in levelling the gun charge during the macropulse and rf power flatness were reported in the 1989 FEL conference. More recent work has concentrated upon the rf master oscillator and electron beam transport, which have lead to reduced macropulse energy spread, as well as decreased position and angle jitter. Also some electron beam diagnostics have been upgraded. The result has been lower macropulse emittance at the entrance to the wiggler.

D.H. Dowell; M.L. Laucks; A.R. Lowrey; M. Bemes; A. Currie; P. Johnson; K. McCrary; J. Adamski; D.R. Shoffstall; A.H. Lumpkin; R.L. Tokar

1991-01-01T23:59:59.000Z

80

Ultrafast x-ray diffraction of laser-irradiated crystals  

SciTech Connect (OSTI)

An apparatus has been developed for measuring time-dependent x-ray diffraction. X-ray pulses from an Advanced Light Source bend magnet are diffracted by a sagittally-focusing Si(111) crystal and then by a sample crystal, presently InSb(111). Laser pulses with 100 fs duration and a repetition rate of 1 KHz irradiate the sample inducing a phase transition. Two types of detectors are being employed: an x-ray streak camera and an avalanche photodiode. The streak camera is driven by a photoconductive switch and has a 2 ps temporal resolution determined by trigger jitter. The avalanche photodiode has high quantum efficiency and sufficient time resolution to detect single x-ray pulses in ALS two bunch or camshaft operation. A beamline is under construction dedicated for time resolved and micro-diffraction experiments. In the new beamline a toroidal mirror collects 3 mrad horizontally and makes a 1:1 image of the bend magnet source in the x-ray hutch. A laser induced phase transition has been observed in InSb occurring within 70 ps.

Heimann, P.A. [Lawrence Berkeley National Lab., CA (US). Advanced Light Source; Larsson, J. [Univ. of California, Berkeley, CA (US). Physics Dept.; Chang, Z. [Univ. of Michigan, Ann Arbor, MI (US). Center for Ultrafast Optical Science

1997-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "x-ray free-electron laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Design considerations for the free-electron laser with the self...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

5 Design considerations for the free-electron laser with the self-seeding and current-enhanced SASE 1 Alexander Zholents Advanced Photon Source, Argonne National Laboratory...

82

Soft x-ray laser microscope. Final report  

SciTech Connect (OSTI)

The program consisted of two phases (Phase I and Phase II). The goal of the Phase I (first year program) was to design and construct the Soft X-ray Laser Contact Microscope. Such microscope was constructed and adapted to PPL`s 18.2nm soft X-ray Laser (SXL), which in turn was modified and prepared for microscopy experiments. Investigation of the photoresist response to 18.2nm laser radiation and transmissivity of 0.1m thick silicion-nitride (Si{sub 3}N{sub 4}) windows were important initial works. The goal of the first year of Phase II was to construct X-ray contact microscope in combination with existing optical phase microscope, already used by biologists. In the second year of Phase II study of dehydrated Horeseshoe Crab and Hela cancer cells were performed with COXRALM. Also during Phase II, the Imaging X-Ray Laser Microscope (IXRALM) was designed and constructed. This paper describes the development of each of the microscopes and their application for research.

Suckewer, P.I.

1990-10-01T23:59:59.000Z

83

Generation of very high-frequency waves by up-conversion in a plasma-loaded free-electron laser  

Science Journals Connector (OSTI)

A free-electron laser loaded with a plasma is able to resonate at two different frequencies. The two waves are copropagating, one with positive slippage while the other has negative slippage. We deduce the nonlinear partial differential equations describing the interaction between the two waves in the slowly-varying-envelope approximation. By injecting a signal at the low frequency, a strong signal is produced at the harmonically related high frequency, with a lethargy time much smaller than that of the spontaneous vacuum emission. This effect could be applied in the generation of very short wavelength radiation, up to the range of hard x rays.

V. Petrillo and C. Maroli

2000-12-01T23:59:59.000Z

84

Ultraviolet Free Electron Laser Facility preliminary design report  

SciTech Connect (OSTI)

This document, the Preliminary Design Report (PDR) for the Brookhaven Ultraviolet Free Electron Laser (UV FEL) facility, describes all the elements of a facility proposed to meet the needs of a research community which requires ultraviolet sources not currently available as laboratory based lasers. Further, for these experiments, the requisite properties are not extant in either the existing second or upcoming third generation synchrotron light sources. This document is the result of our effort at BNL to identify potential users, determine the requirements of their experiments, and to design a facility which can not only satisfy the existing need, but have adequate flexibility for possible future extensions as need dictates and as evolving technology allows. The PDR is comprised of three volumes. In this, the first volume, background for the development of the proposal is given, including descriptions of the UV FEL facility, and representative examples of the science it was designed to perform. Discussion of the limitations and potential directions for growth are also included. A detailed description of the facility design is then provided, which addresses the accelerator, optical, and experimental systems. Information regarding the conventional construction for the facility is contained in an addendum to volume one (IA).

Ben-Zvi, I. (ed.)

1993-02-01T23:59:59.000Z

85

Jefferson Lab's Free-Electron Laser explores promise of carbon...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Webs of nanotubes on collector plates Webs of nanotubes form on collector plates during the collaboration's FEL experiment (image not actual size). Jefferson Lab's Free-Electron...

86

Monte Carlo study for optimal conditions in single-shot imaging with femtosecond x-ray laser pulses  

SciTech Connect (OSTI)

Intense x-ray pulses from x-ray free electron lasers (XFELs) enable the unveiling of atomic structure in material and biological specimens via ultrafast single-shot exposures. As the radiation is intense enough to destroy the sample, a new sample must be provided for each x-ray pulse. These single-particle delivery schemes require careful optimization, though systematic study to find such optimal conditions is still lacking. We have investigated two major single-particle delivery methods: particle injection as flying objects and membrane-mount as fixed targets. The optimal experimental parameters were searched for via Monte Carlo simulations to discover that the maximum single-particle hit rate achievable is close to 40%.

Park, Jaehyun; Ishikawa, Tetsuya; Song, Changyong [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan)] [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Joti, Yasumasa [Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5198 (Japan)] [Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5198 (Japan)

2013-12-23T23:59:59.000Z

87

LIPSS Free-Electron Laser Searches for Dark Matter  

SciTech Connect (OSTI)

A variety of Dark Matter particle candidates have been hypothesized by physics Beyond the Standard Model (BSM) in the very light (10{sup -6} - 10{sup -3} eV) range. In the past decade several international groups have conducted laboratory experiments designed to either produce such particles or extend the boundaries in parameter space. The LIght Pseudo-scalar and Scalar Search (LIPSS) Collaboration, using the 'Light Shining through a Wall' (LSW) technique, passes the high average power photon beam from Jefferson Lab's Free-Electron Laser through a magnetic field upstream from a mirror and optical beam dump. Light Neutral Bosons (LNBs), generated by coupling of photons with the magnetic field, pass through the mirror ('the Wall') into an identical magnetic field where they revert to detectable photons by the same coupling process. While no evidence of LNBs was evident, new scalar coupling boundaries were established. New constraints were also determined for hypothetical para-photons and for millicharged fermions. We will describe our experimental setup and results for LNBs, para-photons, and milli-charged fermions. Plans for chameleon particle searches are underway.

Afanaciev, Andrei; Beard, Kevin; Biallas, George; Boyce, James R; Minarni, M; Ramdon, R; Robinson, Taylor; Shinn, Michelle D

2011-09-01T23:59:59.000Z

88

XTREME OPTICS: the behavior of cavity optics for the Jefferson Lab free-electron laser  

SciTech Connect (OSTI)

The cavity optics within high power free-electron lasers based on energy-recovering accelerators are subjected to extreme conditions associated with illumination from a broad spectrum of radiation, often at high irradiances. This is especially true for the output coupler, where absorption of radiation by both the mirror substrate and coating places significant design restrictions to properly manage heat load and prevent mirror distortion. Besides the fundamental lasing wavelength, the mirrors are irradiated with light at harmonics of the fundamental, THz radiation generated by the bending magnets downstream of the wiggler, and x-rays produced when the electron beam strikes accelerator diagnostic components (e.g., wire scanners and view screens) or from inadvertent beam loss. The optics must reside within high vacuum at ~ 10-8 Torr and this requirement introduces its own set of complications. This talk discusses the performance of numerous high reflector and output coupler optics assemblies and provides a detailed list of lessons learned gleaned from years of experience operating the Upgrade IR FEL, a 10 kW-class, sub-ps laser with output wavelength from 1 to 6 microns.

Michelle D. Shinn; Christopher Behre; Stephen Benson; David Douglas; Fred Dylla; Christopher Gould; Joseph Gubeli; David Hardy; Kevin Jordan; George Neil; and Shukui Zhanga

2006-09-25T23:59:59.000Z

89

Line X-ray emission from Al targets irradiated by high-intensity, variable-length laser pulses  

E-Print Network [OSTI]

Line X-ray emission from Al targets irradiated by high-intensity, variable-length laser pulses J; the scaling rules for the conversion efficiency of the laser radiation into the line X-ray emission are discussed. Keywords: Laser-produced plasma; Line X-ray emission; X-ray sources; X-ray spectroscopy 1

Limpouch, Jiri

90

Beam energy distribution influences on density modulation efficiency in seeded free-electron lasers  

E-Print Network [OSTI]

The beam energy spread at the entrance of undulator system is of paramount importance for efficient density modulation in high-gain seeded free-electron lasers (FELs). In this paper, the dependences of high harmonic micro-bunching in the high-gain harmonic generation (HGHG), echo-enabled harmonic generation (EEHG) and phase-merging enhanced harmonic generation (PEHG) schemes on the electron energy spread distribution are studied. Theoretical investigations and multi-dimensional numerical simulations are applied to the cases of uniform and saddle beam energy distributions and compared to a traditional Gaussian distribution. It shows that the uniform and saddle electron energy distributions significantly enhance the performance of HGHG-FELs, while they almost have no influence on EEHG and PEHG schemes. A numerical example demonstrates that, with about 84keV RMS uniform and/or saddle slice energy spread, the 30th harmonic radiation can be directly generated by a single-stage seeding scheme for a soft x-ray FEL f...

Wang, Guanglei; Deng, Haixiao; Zhang, Weiqing; Wu, Guorong; Dai, Dongxu; Wang, Dong; Zhao, Zhentang; Yang, Xueming

2015-01-01T23:59:59.000Z

91

Gain dynamics in a soft X-ray laser ampli er perturbed by a strong injected X-ray eld  

SciTech Connect (OSTI)

Seeding soft X-ray plasma ampli ers with high harmonics has been demonstrated to generate high-brightness soft X-ray laser pulses with full spatial and temporal coherence. The interaction between the injected coherent eld and the swept-gain medium has been modelled. However, no exper- iment has been conducted to probe the gain dynamics when perturbed by a strong external seed eld. Here, we report the rst X-ray pump X-ray probe measurement of the nonlinear response of a plasma ampli er perturbed by a strong soft X-ray ultra-short pulse. We injected a sequence of two time-delayed high-harmonic pulses (l518.9 nm) into a collisionally excited nickel-like molybdenum plasma to measure with femto-second resolution the gain depletion induced by the saturated ampli cation of the high-harmonic pump and its subsequent recovery. The measured fast gain recovery in 1.5 1.75 ps con rms the possibility to generate ultra-intense, fully phase-coherent soft X-ray lasers by chirped pulse ampli cation in plasma ampli ers.

Wang, Yong [Colorado State University, Fort Collins] [Colorado State University, Fort Collins; Wang, Shoujun [Colorado State University, Fort Collins] [Colorado State University, Fort Collins; Oliva, E [Laboratoire de Physique des Gaz et des Gaz et des Plasmas] [Laboratoire de Physique des Gaz et des Gaz et des Plasmas; Lu, L [Laboratoire de Physique des Gaz et des Gaz et des Plasmas] [Laboratoire de Physique des Gaz et des Gaz et des Plasmas; Berrill, Mark A [ORNL] [ORNL; Yin, Liang [Colorado State University, Fort Collins] [Colorado State University, Fort Collins; Nejdl, J [Colorado State University, Fort Collins] [Colorado State University, Fort Collins; Luther, Brad [Colorado State University, Fort Collins] [Colorado State University, Fort Collins; Proux, C [Laboratoire d’Optique Applique´e, ENSTA, CNRS, Ecole Polytechnique] [Laboratoire d’Optique Applique´e, ENSTA, CNRS, Ecole Polytechnique; Le, T. T. [Laboratoire de Physique des Gaz et des Gaz et des Plasmas] [Laboratoire de Physique des Gaz et des Gaz et des Plasmas; Dunn, James [Lawrence Livermore National Laboratory (LLNL)] [Lawrence Livermore National Laboratory (LLNL); Ros, D [Laboratoire de Physique des Gaz et des Gaz et des Plasmas] [Laboratoire de Physique des Gaz et des Gaz et des Plasmas; Zeitoun, Philippe [École Polytechnique] [École Polytechnique; Rocca, Jorge [Colorado State University, Fort Collins] [Colorado State University, Fort Collins

2014-01-01T23:59:59.000Z

92

Supplemental information I. OPTICAL-LASER AND X-RAY CONFIGURATION  

E-Print Network [OSTI]

Supplemental information I. OPTICAL-LASER AND X-RAY CONFIGURATION The experiment used 70 fs x-ray and x-ray pulses was established by the initial decrease in the 111 diffraction peak in a laser pulses at 10 keV from the LCLS in the high-charge (250 pC) mode at 120 Hz. The x-ray beam was focused

Loss, Daniel

93

Part 2: Coherent emission from Free Electron Lasers  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

0 0 Electron beam-based sources of ultrashort x-ray pulses Alexander Zholents Advanced Photon Source, Argonne National Laborator , Argonne, IL 60439 (September 7, 2010) To be published by World Scientific Publishing Co. in Reviews of Accelerator Science and Technology. y 2 Electron beam-based sources of ultrashort x-ray pulses * Alexander Zholents Argonne National Laboratory, Advanced Photon Source, 9700 South Cass Ave., Argonne, IL 60439 Abstract A review of various methods for generation of ultrashort x-ray pulses using relativistic electron beam from conventional accelerators is presented. Both spontaneous and coherent emission of electrons is considered. Introduction The importance of the time-resolved studies of matter at picosecond (ps),

94

Laser wakefield generated X-ray probe for femtosecond time-resolved measurements of ionization states of warm dense aluminum  

SciTech Connect (OSTI)

We have developed a laser wakefield generated X-ray probe to directly measure the temporal evolution of the ionization states in warm dense aluminum by means of absorption spectroscopy. As a promising alternative to the free electron excited X-ray sources, Betatron X-ray radiation, with femtosecond pulse duration, provides a new technique to diagnose femtosecond to picosecond transitions in the atomic structure. The X-ray probe system consists of an adjustable Kirkpatrick-Baez (KB) microscope for focusing the Betatron emission to a small probe spot on the sample being measured, and a flat Potassium Acid Phthalate Bragg crystal spectrometer to measure the transmitted X-ray spectrum in the region of the aluminum K-edge absorption lines. An X-ray focal spot size of around 50 ?m was achieved after reflection from the platinum-coated 10-cm-long KB microscope mirrors. Shot to shot positioning stability of the Betatron radiation was measured resulting in an rms shot to shot variation in spatial pointing on the sample of 16 ?m. The entire probe setup had a spectral resolution of ?1.5 eV, a detection bandwidth of ?24 eV, and an overall photon throughput efficiency of the order of 10{sup ?5}. Approximately 10 photons were detected by the X-ray CCD per laser shot within the spectrally resolved detection band. Thus, it is expected that hundreds of shots will be required per absorption spectrum to clearly observe the K-shell absorption features expected from the ionization states of the warm dense aluminum.

Mo, M. Z.; Chen, Z.; Tsui, Y. Y.; Fedosejevs, R. [Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Alberta T6G 2V4 (Canada)] [Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Alberta T6G 2V4 (Canada); Fourmaux, S.; Saraf, A.; Otani, K.; Kieffer, J. C. [INRS-EMT, Université du Québec, 1650 Lionel Boulet, Varennes, Québec J3X 1S2 (Canada)] [INRS-EMT, Université du Québec, 1650 Lionel Boulet, Varennes, Québec J3X 1S2 (Canada); Ng, A. [Department of Physics and Astronomy, University of British Columbia, British Columbia V6T 1Z1 (Canada)] [Department of Physics and Astronomy, University of British Columbia, British Columbia V6T 1Z1 (Canada)

2013-12-15T23:59:59.000Z

95

Free Electron Laser Program Program at TJNAF| U.S. DOE Office of Science  

Office of Science (SC) Website

Free Electron Laser Program Program at Free Electron Laser Program Program at TJNAF Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Spinoff Applications Spinoff Archives SBIR/STTR Applications of Nuclear Science and Technology Funding Opportunities Nuclear Science Advisory Committee (NSAC) News & Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3613 F: (301) 903-3833 E: sc.np@science.doe.gov More Information » Spinoff Archives Free Electron Laser Program Program at TJNAF Print Text Size: A A A RSS Feeds FeedbackShare Page Application/instrumentation: Free Electron Laser (FEL) Program Developed at: Thomas Jefferson National Laboratory Developed in: 1990's - 2010

96

Toward resistant vacuum-ultraviolet coatings for free-electron lasers down to 150 nm  

SciTech Connect (OSTI)

Research and development are currently trying to run a storage ring free-electron laser down to 150 nm with robust optics. Vacuum-ultraviolet fluoride optics with protected oxide layers and enhanced metallic mirrors are investigated.

Gatto, Alexandre; Yang Minghong; Kaiser, Norbert; Guenster, Stefan; Ristau, Detlev; Trovo, Mauro; Danailov, Miltcho

2006-10-01T23:59:59.000Z

97

A CW normal-conductive RF gun for free electron laser and energy recovery linac applications  

E-Print Network [OSTI]

Todd, State-of-the art electron guns and injector de- signs,7] Summary of working group on guns and injectors, 41st Ad-A CW normal-conductive RF gun for free electron laser and

Baptiste, Kenneth

2009-01-01T23:59:59.000Z

98

Massively parallel X-ray holography STEFANO MARCHESINI1,2  

E-Print Network [OSTI]

, and a bacterial cell with a soft-X-ray free-electron laser, where illumination by a single 15-fs pulse was successfully used in producing the holographic image. As X-ray lasers move to shorter wavelengths we expectMassively parallel X-ray holography STEFANO MARCHESINI1,2 *, SE´BASTIEN BOUTET3,4 , ANNE E

Petta, Jason

99

Apparatus and method to enhance X-ray production in laser produced plasmas  

DOE Patents [OSTI]

Method and apparatus for generating x-rays for use in, for instance, x-ray photolithography is disclosed. The method of generating x-rays includes the steps of providing a target and irradiating the target with a laser system which produces a train of sub-pulses to generate an x-ray producing plasma. The sub-pulses are of both high intensity and short duration. The apparatus for generating x-rays from a plasma includes a vacuum chamber, a target supported within the chamber and a laser system, including a short storage time laser. 8 figs.

Augustoni, A.L.; Gerardo, J.B.; Raymond, T.D.

1992-12-29T23:59:59.000Z

100

Apparatus and method to enhance X-ray production in laser produced plasmas  

DOE Patents [OSTI]

Method and apparatus for generating x-rays for use in, for instance, x-ray photolithography. The method of generating x-rays includes the steps of providing a target and irradiating the target with a laser system which produces a train of sub-pulses to generate an x-ray producing plasma. The sub-pulses are of both high intensity and short duration. The apparatus for generating x-rays from a plasma includes a vacuum chamber, a target supported within the chamber and a laser system, including a short storage time laser.

Augustoni, Arnold L. (Albuquerque, NM); Gerardo, James B. (Albuquerque, NM); Raymond, Thomas D. (Albuquerque, NM)

1992-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "x-ray free-electron laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

High-Gain Harmonic-Generation Free-Electron Laser  

Science Journals Connector (OSTI)

...originally built by STI Optronics for use in a visible FEL at Boeing. 35 Recent theoretical work on generating...originally built by STI Optronics for use in a visible FEL at Boeing. Recent theoretical work on generating hard x-rays by cascading...

L.-H. Yu; M. Babzien; I. Ben-Zvi; L. F. DiMauro; A. Doyuran; W. Graves; E. Johnson; S. Krinsky; R. Malone; I. Pogorelsky; J. Skaritka; G. Rakowsky; L. Solomon; X. J. Wang; M. Woodle; V. Yakimenko; S. G. Biedron; J. N. Galayda; E. Gluskin; J. Jagger; V. Sajaev; I. Vasserman

2000-08-11T23:59:59.000Z

102

Bright High Average Power Table-top Soft X-Ray Lasers  

SciTech Connect (OSTI)

We have demonstrated the generation of bright soft x-ray laser pulses with record-high average power from compact plasma amplifiers excited by ultrafast solid state lasers. These lasers have numerous applications in nanoscience and nanotechnology.

Rocca, Jorge [Colorado State University, Fort Collins; Reagan, Brendon [Colorado State University, Fort Collins; Wernsing, Keith [Colorado State University, Fort Collins; Luther, Brad [Colorado State University, Fort Collins; Curtis, Alden [Colorado State University, Fort Collins; Nichols,, Anthony [Colorado State University, Fort Collins; Wang, Yong [Colorado State University, Fort Collins; Alessi, David [Colorado State University, Fort Collins; Martz, Dale [Colorado State University, Fort Collins; Yin, Liang [Colorado State University, Fort Collins; Wang, Shoujun [Colorado State University, Fort Collins; Berrill, Mark A [ORNL; Furch, Federico [Colorado State University, Fort Collins; Woolston, Mark [Colorado State University, Fort Collins; Patel, Dinesh [Colorado State University, Fort Collins; Marconi, Mario [Colorado State University, Fort Collins; Menoni, Carmen [Colorado State University, Fort Collins

2012-01-01T23:59:59.000Z

103

Single molecule imaging with longer x-ray laser pulses  

E-Print Network [OSTI]

In serial femtosecond crystallography, x-ray laser pulses do not need to outrun all radiation damage processes because Bragg diffraction exceeds the damage-induced background scattering for longer pulses ($\\sim$ 50--100 fs). This is due to a "self-gating pulse" effect whereby damage terminates Bragg diffraction prior to the pulse completing its passage through the sample, as if that diffraction were produced by a shorter pulse of equal fluence. We show here that a similar gating effect applies to single molecule diffraction with respect to spatially uncorrelated damage processes like ionization and ion diffusion. The effect is clearly seen in calculations of the diffraction contrast, by calculating the diffraction of average structure separately to the diffraction from statistical fluctuations of the structure due to damage ("damage noise"). Our results suggest that sub-nanometer single molecule imaging with longer pulses, like those produced at currently operating facilities, should not yet be ruled out. The...

Martin, Andrew V; Caleman, Carl; Quiney, Harry M

2015-01-01T23:59:59.000Z

104

Secretary Chu Dedicates World's Most Powerful X-ray Laser | Department of  

Broader source: Energy.gov (indexed) [DOE]

Dedicates World's Most Powerful X-ray Laser Dedicates World's Most Powerful X-ray Laser Secretary Chu Dedicates World's Most Powerful X-ray Laser August 16, 2010 - 12:00am Addthis Washington, D.C. - U.S. Energy Secretary Steven Chu today dedicated the Linac Coherent Light Source (LCLS), the world's first and most powerful X-ray laser, at the Department of Energy's SLAC National Accelerator Laboratory. The LCLS will play an essential role in addressing the scientific needs of the 21st century by exploring new ways to create better energy sources and enabling advances in a range of scientific fields. The LCLS produces pulses of X-rays more than a billion times brighter than the most powerful existing sources. The ultrafast X-ray pulses are used much like flashes from a high-speed strobe light, enabling scientists to take

105

Free electron properties of metals under ultrafast laser-induced electron-phonon nonequilibrium: a first-principles study  

E-Print Network [OSTI]

Free electron properties of metals under ultrafast laser-induced electron-phonon nonequilibrium CEA-DIF, 91297 Arpajon, France (Dated: April 3, 2014) The electronic behavior of various solid metals modelled based on the free electron classical theory, the free electron number is a key parameter. However

Paris-Sud XI, Université de

106

INEX (integrated numerical experiment) simulations of the Los Alamos HIBAF (high-brightness accelerator free-electron laser) free-electron laser MOPA (master oscillator power amplifier) experiment  

SciTech Connect (OSTI)

We present results of Integrated Numerical Experiment (INEX) simulations of the performance of a 1-m untapered wiggler FEL oscillator driving a 2-m wiggler FEL amplifier for the new HIBAF (High-Brightness Accelerator Free-Electron Laser) facility at Los Alamos. INEX simulations utilize a numerically-generated electron micropulse, from ISIS/PARMELA calculations of the photoinjector/linac/beam transport system, in the 3-D FEL simulation code FELEX. 13 refs., 10 figs., 1 tab.

Goldstein, J.C.; Carlsten, B.E.; McVey, B.D.

1989-01-01T23:59:59.000Z

107

Optically-ionized plasma recombination x-ray lasers  

SciTech Connect (OSTI)

Design studies for recombination x-ray lasers based on plasmas ionized by high intensity, short pulse optical lasers are presented. Transient lasing on n = 3 to n = 2 transitions in Lithium-like Neon allows for moderately short wavelengths ({le} 100{angstrom}) without requiring ionizing intensities associated with relativistic electron quiver energies. The electron energy distribution following the ionizing pulse affects directly the predicted gains for this resonance transition. Efficiencies of 10{sup {minus}6} or greater are found for plasma temperatures in the vicinity of 40 eV. Simulation studies of parametric heating phenomena relating to stimulated Raman and Compton scattering are presented. For electron densities less than about 2.5 {times} 10{sup 20} cm{sup {minus}3} and peak driver intensity of 2 {times} 10{sup 17} W/cm{sup 2} at 0.25 {mu}m with pulse length of 100 fsec, the amount of electron heating is found to be marginally significant. For Lithium-like Aluminum, the required relativistic ionizing intensity gives excessive electron heating and reduced efficiency, thereby rendering this scheme impractical for generating shorter wavelength lasing ({le} 50{angstrom}) in the transient case. Following the transient lasing phase, a slow hydrodynamic expansion into the surrounding cool plasma is accompanied by quasi-static gain on the n = 4 to n = 3 transition in Lithium-like Neon. Parametric heating effects on gain optimization in this regime are also discussed. 18 refs., 6 figs.

Amendt, P.; Eder, D.C.; Wilks, S.C.; Dunning, M.J.; Keane, C.J.

1991-01-18T23:59:59.000Z

108

Using the X-FEL to photo-pump X-ray laser transitions in He-like Ne  

SciTech Connect (OSTI)

Nearly four decades ago H-like and He-like resonantly photo-pumped laser schemes were proposed for producing X-ray lasers. However, demonstrating these schemes in the laboratory has proved to be elusive because of the difficulty of finding a strong resonant pump line. With the advent of the X-ray free electron laser (X-FEL) at the SLAC Linac Coherent Light Source (LCLS) we now have a tunable X-ray laser source that can be used to replace the pump line in previously proposed laser schemes and allow researchers to study the physics and feasibility of resonantly photo-pumped laser schemes. In this paper we use the X-FEL at 1174 eV to photo-pump the singly excited 1s2p state of He-like Ne to the doubly excited 2p3p state and model gain on the 2p3p-2p2s transition at 175 eV and the 2p3p-1s3p transition at 1017 eV. One motivation for studying this scheme is to explore possible quenching of the gain due to strong non-linear coupling effects from the intense X-FEL beam We compare this scheme with photo-pumping the He-like Ne ground state to the 1s3p singly excited state followed by lasing on the 3p-2s and 3d-2p transitions at 158 and 151 eV. Experiments are being planned at LCLS to study these laser processes and coherent quantum effects.

Nilsen, J; Rohringer, N

2011-08-30T23:59:59.000Z

109

ANALYSIS AND MITIGATION OF X-RAY HAZARD GENERATED FROM HIGH INTENSITY LASER-TARGET INTERACTIONS  

SciTech Connect (OSTI)

Interaction of a high intensity laser with matter may generate an ionizing radiation hazard. Very limited studies have been made, however, on the laser-induced radiation protection issue. This work reviews available literature on the physics and characteristics of laser-induced X-ray hazards. Important aspects include the laser-to-electron energy conversion efficiency, electron angular distribution, electron energy spectrum and effective temperature, and bremsstrahlung production of X-rays in the target. The possible X-ray dose rates for several femtosecond Ti:sapphire laser systems used at SLAC, including the short pulse laser system for the Matter in Extreme Conditions Instrument (peak power 4 TW and peak intensity 2.4 x 10{sup 18} W/cm{sup 2}) were analysed. A graded approach to mitigate the laser-induced X-ray hazard with a combination of engineered and administrative controls is also proposed.

Qiu, R.; Liu, J.C.; Prinz, A.A.; Rokni, S.H.; Woods, M.; Xia, Z.; /SLAC; ,

2011-03-21T23:59:59.000Z

110

Method and apparatus for producing durationally short ultraviolet or x-ray laser pulses  

DOE Patents [OSTI]

A method and apparatus is disclosed for producing ultraviolet or x- ray laser pulses of short duration. An ultraviolet or x-ray laser pulse of long duration is progressively refracted, across the surface of an opaque barrier, by a streaming plasma that is produced by illuminating a solid target with a pulse of conventional line focused high power laser radiation. The short pulse of ultraviolet or x-ray laser radiation, which may be amplified to high power, is separated out by passage through a slit aperture in the opaque barrier.

MacGowan, B.J.; Matthews, D.L.; Trebes, J.E.

1987-05-05T23:59:59.000Z

111

Method and apparatus for producing durationally short ultraviolet or X-ray laser pulses  

DOE Patents [OSTI]

A method and apparatus is disclosed for producing ultraviolet or X-ray laser pulses of short duration (32). An ultraviolet or X-ray laser pulse of long duration (12) is progressively refracted, across the surface of an opaque barrier (28), by a streaming plasma (22) that is produced by illuminating a solid target (16, 18) with a pulse of conventional line focused high power laser radiation (20). The short pulse of ultraviolet or X-ray laser radiation (32), which may be amplified to high power (40, 42), is separated out by passage through a slit aperture (30) in the opaque barrier (28).

MacGowan, Brian J. (Livermore, CA); Matthews, Dennis L. (El Granada, CA); Trebes, James E. (Livermore, CA)

1988-01-01T23:59:59.000Z

112

Accurate macromolecular structures using minimal measurements from X-ray free-electron lasers  

SciTech Connect (OSTI)

Diffraction patterns from thermolysin microcrystals and one dark run, collected in December 2011. This data was used for metrology calibration and general cctbx.xfel development.

Hattne, Hattne

2014-03-04T23:59:59.000Z

113

De novo protein crystal structure determination from X-ray free-electron laser data  

SciTech Connect (OSTI)

Serial femtosecond crystallography (SFX) data of microcrystals of a lysozyme gadolinium derivative. The data was used to demonstrate de-novo phasing by single anomalous dispersion.

Barends, Thomas, R.M.

2013-11-25T23:59:59.000Z

114

Accurate macromolecular structures using minimal measurements from X-ray free-electron lasers  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

Diffraction patterns from thermolysin microcrystals and one dark run, collected in December 2011. This data was used for metrology calibration and general cctbx.xfel development.

Hattne, Hattne

115

De novo protein crystal structure determination from X-ray free-electron laser data  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

Serial femtosecond crystallography (SFX) data of microcrystals of a lysozyme gadolinium derivative. The data was used to demonstrate de-novo phasing by single anomalous dispersion.

Barends, Thomas, R.M.

116

R&D for a Soft X-Ray Free Electron Laser Facility  

E-Print Network [OSTI]

Quantum-degenerate Electron Source, Physical Review LettersHigh brightness electron source, beam instrumentation andFEL Requires high rep-rate electron source Beam switchyard

Staples, John

2009-01-01T23:59:59.000Z

117

Standoff detection of hidden objects using backscattered ultra-intense laser-produced x-rays  

SciTech Connect (OSTI)

Ultra-intense laser-produced sub-ps X-ray pulses can detect backscattered signals from objects hidden in aluminium containers. Coincident measurements using primary X-rays enable differentiation among acrylic, copper, and lead blocks inside the container. Backscattering reveals the shapes of the objects, while their material composition can be identified from the modification methods of the energy spectra of backscattered X-ray beams. This achievement is an important step toward more effective homeland security.

Kuwabara, H. [IHI Corporation, 1, Shin-Nakahara-cho, Isogo-ku, Yokohama 235-8501 (Japan)] [IHI Corporation, 1, Shin-Nakahara-cho, Isogo-ku, Yokohama 235-8501 (Japan); Mori, Y.; Kitagawa, Y. [The Graduate School for the Creation of New Photonics Industries, 1955-1 Kurematsucho, Nishiku, Hamamatsu, Shizuoka 431-1202 (Japan)] [The Graduate School for the Creation of New Photonics Industries, 1955-1 Kurematsucho, Nishiku, Hamamatsu, Shizuoka 431-1202 (Japan)

2013-08-28T23:59:59.000Z

118

Soft x-ray resist characterization: Studies with a laser plasma x-ray source  

SciTech Connect (OSTI)

Little work has been performed to characterize the exposure sensitivity, contrast, and tone of candidate resists for photon energies between 100--300 eV, the range in which projection soft x-ray lithography will be developed. We report here the characterization of near-edge x-ray absorption fine structure (NEXAFS) spectra, exposure sensitivity, contrast, and post-exposure processing of selected polysilane resists at photon energies close to the Si L{sub 2,3} absorption edge (100 eV). We find absorption resonance features in the NEXAFS spectra which we assign to excitation into Si--Si and Si--C {sigma}* orbitals. Using monochromatized XUV exposures on the Si--Si {sigma}* resonance at 105 eV, followed by solvent dissolution development, we have measured the exposure sensitivity curves of these resists. We find sensitivities in the range of 600--3000 mJ/cm{sup 2} and contrasts in the range from 0.5--1.4, depending on the polysilane side chain. We have also performed exposure sensitivity measurements at 92 eV, below the edge. Sensitivity decreases slightly compared to 105 eV exposures and the saturation depth and contrast both increase, as expected. We find also that exposing resist films to oxygen after XUV exposure, but before development increases the sensitivity markedly. 7 figs.

Kubiak, G.D.; Outka, D.A. (Sandia National Labs., Livermore, CA (USA)); Zeigler, J.M. (Sandia National Labs., Albuquerque, NM (USA))

1990-01-01T23:59:59.000Z

119

Enhancement of x-ray line emission from plasmas produced by short high-intensity laser double pulses  

E-Print Network [OSTI]

Enhancement of x-ray line emission from plasmas produced by short high-intensity laser double laser-produced plasmas are bright ultrafast line x-ray sources potentially suitable for different onto a solid target into the x-ray emission is significantly enhanced when a laser prepulse precedes

Limpouch, Jiri

120

Production of a keV X-Ray Beam from Synchrotron Radiation in Relativistic Laser-Plasma Interaction  

E-Print Network [OSTI]

Production of a keV X-Ray Beam from Synchrotron Radiation in Relativistic Laser-Plasma Interaction demonstrate that a beam of x-ray radiation can be generated by simply focusing a single high- intensity laser spectral range) [6]. Laser-driven K x-ray sources [7­9] radiate subnanometer wavelength radiation

Umstadter, Donald

Note: This page contains sample records for the topic "x-ray free-electron laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

X-Ray Radiation from Nonlinear Thomson Scattering of an Intense Femtosecond Laser on Relativistic Electrons in a Helium Plasma  

E-Print Network [OSTI]

X-Ray Radiation from Nonlinear Thomson Scattering of an Intense Femtosecond Laser on Relativistic laser beam on plasma electrons. A collimated x-ray radiation with a broad continuous spectrum peaked by the ultraintense laser fields. The results show the existence of several physical mecha- nisms for the x-ray

Umstadter, Donald

122

Photon statistics in a free-electron laser with an axial-guide magnetic field  

Science Journals Connector (OSTI)

Starting from an initial state with an electron energy p02/2m+??c/2, a vacuum-laser field, and a coherent wiggler field, I discuss photon statistics in a free-electron laser with an axial-guide magnetic field. It is found that the axial field can weaken the squeezing, enhance the positive (for ?>0) and negative (for ?0) and antibunching (for ?<0).

Gou San-kui

1992-07-15T23:59:59.000Z

123

Making the Old New Again: Measuring Ultrashort X-ray Laser Pulses...  

Office of Science (SC) Website

free-electron lasers using a transverse deflector." Physical Review ST Accelerators and Beams. 14:120701 (2011). DOI: 10.1103PhysRevSTAB.14.120701 External link V. A. Dolgashev...

124

Demonstration of Laser Induced X-Ray Generation in an Expanding Laser Produced Plasma  

Science Journals Connector (OSTI)

X-ray emission at 10 nm stimulated by visible laser radiation at 614.2 nm in a beryllium laser produced plasma was investigated. A method of laser induced quenching of metastable ions was applied to He-like Be2+ ions in the 1s2s 1S0 state. Laser excitation to the 1s2p 1P1 state was followed by an intense x-ray emission at a resonance 1s2 1S0-1s2p 1P1 transition. Time, angular, and polarization characteristics of the radiation were studied; a linear polarization and a dipole type angular distribution have been found. The total energy radiated in a 1.5 ns pulse amounted to 10 ?J.

D. M. Simanovskii, A. N. Gladskikh, L. A. Shmaenok, and S. V. Bobashev

1996-07-29T23:59:59.000Z

125

Time-resolved protein nanocrystallography using an X-ray free...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Time-resolved protein nanocrystallography using an X-ray free-electron laser Authors: Aquila, A., Hunter, M. S., Doak, R. B., Kirian, R. A., Fromme, P., White, T. A., Andreasson,...

126

Instantaneous x-ray radiation energy from laser produced polystyrene plasmas for shock ignition conditions  

SciTech Connect (OSTI)

Laser target energy coupling mechanism is crucial in the shock ignition (SI) scheme, and x-ray radiation energy is a non-negligible portion of the laser produced plasma energy. To evaluate the x-ray radiation energy amount at conditions relevant to SI scheme, instantaneous x-ray radiation energy is investigated experimentally with continuum phase plates smoothed lasers irradiating layer polystyrene targets. Comparative laser pulses without and with shock spike are employed. With the measured x-ray angular distribution, full space x-ray radiation energy and conversion efficiency are observed. Instantaneous scaling law of x-ray conversion efficiency is obtained as a function of laser intensity and time. It should be pointed out that the scaling law is available for any laser pulse shape and intensity, with which irradiates polystyrene planar target with intensity from 2 × 10{sup 14} to 1.8 × 10{sup 15} W/cm{sup 2}. Numerical analysis of the laser energy transformation is performed, and the simulation results agree with the experimental data.

Shang, Wanli; Wei, Huiyue; Li, Zhichao; Yi, Rongqing; Zhu, Tuo; Song, Tianmin; Huang, Chengwu; Yang, Jiamin [Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900 (China)] [Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900 (China)

2013-10-15T23:59:59.000Z

127

Lab Breakthrough: X-ray Laser Captures Atoms and Molecules in Action |  

Broader source: Energy.gov (indexed) [DOE]

X-ray Laser Captures Atoms and Molecules in X-ray Laser Captures Atoms and Molecules in Action Lab Breakthrough: X-ray Laser Captures Atoms and Molecules in Action July 18, 2012 - 12:51pm Addthis The Linac Coherent Light Source at SLAC is the world's most powerful X-ray laser, which helps researchers understand the extreme conditions found in the hearts of stars and giant planets guiding research into nuclear fusion, the mechanism that powers the sun. View the entire Lab Breakthrough playlist. Michael Hess Michael Hess Former Digital Communications Specialist, Office of Public Affairs How is the LCLS different? Rather than accelerate particles to collide them, it accelerates particles in a special way to create extremely bright bunches of photons. These pulses are about 10 billion times brighter and one thousand

128

Development of a Time-resolved Soft X-ray Spectrometer for Laser Produced Plasma Experiments  

SciTech Connect (OSTI)

A 2400 line/mm variable spaced grating spectrometer (VSG) has been used to measure soft x-ray emission (8-22 {angstrom}) from laser-produced plasma experiments at Lawrence Livermore National Laboratory's Compact Multipulse Terrawatt (COMET) Laser Facility. The spectrometer was coupled to a Kentech x-ray streak camera to study the temporal evolution of soft x-rays emitted from the back of mylar and copper foils irradiated at 10{sup 15} W/cm{sup 2}. The instrument demonstrated a resolving power of {approx} 120 at 19 {angstrom} with a time resolution of 31 ps. The time-resolved copper emission spectrum was consistent with a photodiode monitoring the laser temporal pulse shape and indicated that the soft x-ray emission follows the laser heating of the target. The time and spectral resolution of this diagnostic make it useful for studies of high temperature plasmas.

Cone, K V; Dunn, J; Schneider, M B; Baldis, H A; Brown, G V; Emig, J; James, D L; May, M J; Park, J; Shepherd, R; Widmann, K

2010-05-12T23:59:59.000Z

129

Development of a time-resolved soft x-ray spectrometer for laser produced plasma experiments  

SciTech Connect (OSTI)

A 2400 lines/mm variable-spaced grating spectrometer has been used to measure soft x-ray emission (8-22 A) from laser-produced plasma experiments at Lawrence Livermore National Laboratory's Compact Multipulse Terrawatt (COMET) Laser Facility. The spectrometer was coupled to a Kentech x-ray streak camera to study the temporal evolution of soft x rays emitted from the back of the Mylar and the copper foils irradiated at 10{sup 15} W/cm{sup 2}. The instrument demonstrated a resolving power of {approx}120 at 19 A with a time resolution of 31 ps. The time-resolved copper emission spectrum was consistent with a photodiode monitoring the laser temporal pulse shape and indicated that the soft x-ray emission follows the laser heating of the target. The time and spectral resolutions of this diagnostic make it useful for studies of high temperature plasmas.

Cone, K. V.; Park, J. [Lawrence Livermore National Laboratory, Livermore, California 94551 (United States); University of California at Davis, Davis, California 95616 (United States); Dunn, J.; Schneider, M. B.; Brown, G. V.; Emig, J.; James, D. L.; May, M. J.; Shepherd, R.; Widmann, K. [Lawrence Livermore National Laboratory, Livermore, California 94551 (United States); Baldis, H. A. [University of California at Davis, Davis, California 95616 (United States)

2010-10-15T23:59:59.000Z

130

Science at the Timescale of the Electron: Tabletop X-ray Lasers...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

of the Electron: Tabletop X-ray Lasers and Applications in Nanoscience and Nanotechnology November 21, 2014 11:00AM to 12:00PM Presenter Margaret Murnane, University of...

131

Development of Focused Laser Plasma X-ray Beam for Radiobiological Applications  

Science Journals Connector (OSTI)

We have started to develop a laser plasma x-ray microbeam irradiation system, and demonstrated a preliminary study of the cell survival and gamma-H2AX focus formation in the culture...

NISHIKINO, Masaharu; SATO, Katsutoshi; OHSHIMA, Shinsuke; HASEGAWA, Noboru; ISHINO, Masahiko; KAWACHI, Tetsuya; OKANO, Yasuaki; NUMASAKI, Hodaka; TESHIMA, Teruki; Nishimura, Hiroaki

132

Plasma-Density Determination from X-Ray Radiography of Laser-Driven Spherical Implosions  

E-Print Network [OSTI]

The fuel layer density of an imploding laser-driven spherical shell is inferred from framed x-ray radiographs. The density distribution is determined by using Abel inversion to compute the radial distribution of the opacity ...

Frenje, Johan A.

133

Low-Emittance Electron Bunches from a Laser-Plasma Accelerator Measured using Single-Shot X-Ray Spectroscopy  

E-Print Network [OSTI]

Low-Emittance Electron Bunches from a Laser-Plasma Accelerator Measured using Single-Shot X-Ray,8], x-ray [9­11], and -ray radiation [12,13]. The electron density wave gener- ated by an intense laser manuscript received 15 February 2012; published 10 August 2012) X-ray spectroscopy is used to obtain single

Geddes, Cameron Guy Robinson

134

Status of the visible Free-Electron Laser at the Brookhaven Accelerator Test Facility  

SciTech Connect (OSTI)

The 500 nm Free-Electron Laser (ATF) of the Brookhaven National Laboratory is reviewed. We present an overview of the ATF, a high-brightness, 50-MeV, electron accelerator and laser complex which is a users' facility for accelerator and beam physics. A number of laser acceleration and FEL experiments are under construction at the ATF. The visible FEL experiment is based on a novel superferric 8.8 mm period undulator. The electron beam parameters, the undulator, the optical resonator, optical and electron beam diagnostics are discussed. The operational status of the experiment is presented. 22 refs., 7 figs.

Batchelor, K.; Ben-Zvi, I.; Fernow, R.C.; Fisher, A.S.; Friedman, A.; Gallardo, J.; Ingold, G.; Kirk, H.; Kramer, S.; Lin, L.; Rogers, J.T.; Sheehan, J.F.; van Steenbergen, A.; Woodle, M.; Xie, J.; Yu, L.H.; Zhang, R. (Brookhaven National Lab., Upton, NY (United States)); Bhowmik, A. (Rockwell International Corp., Canoga Park, CA (United States). Rocketdyne Div.)

1991-01-01T23:59:59.000Z

135

Compact scanning soft-x-ray microscope using a laser-produced plasma source and normal-incidence multilayer mirrors  

Science Journals Connector (OSTI)

We have constructed a scanning soft-x-ray microscope that uses a laser-produced plasma as the soft-x-ray source and normal-incidence multilayer-coated mirrors in a Schwarzschild...

Trail, J A; Byer, R L

1989-01-01T23:59:59.000Z

136

Dispersion relation and growth rate in a Cherenkov free electron laser: Finite axial magnetic field  

SciTech Connect (OSTI)

A theoretical analysis is presented for dispersion relation and growth rate in a Cherenkov free electron laser with finite axial magnetic field. It is shown that the growth rate and the resonance frequency of Cherenkov free electron laser increase with increasing axial magnetic field for low axial magnetic fields, while for high axial magnetic fields, they go to a saturation value. The growth rate and resonance frequency saturation values are exactly the same as those for infinite axial magnetic field approximation. The effects of electron beam self-fields on growth rate are investigated, and it is shown that the growth rate decreases in the presence of self-fields. It is found that there is an optimum value for electron beam density and Lorentz relativistic factor at which the maximum growth rate can take place. Also, the effects of velocity spread of electron beam are studied and it is found that the growth rate decreases due to the electron velocity spread.

Kheiri, Golshad; Esmaeilzadeh, Mahdi [Department of Physics, Iran University of Science and Technology, Tehran 16844 (Iran, Islamic Republic of)] [Department of Physics, Iran University of Science and Technology, Tehran 16844 (Iran, Islamic Republic of)

2013-12-15T23:59:59.000Z

137

Time-dependent simulation of prebunched one and two-beam free electron laser  

SciTech Connect (OSTI)

A numerical simulation in one-dimension is conducted to study the slippage effects on prebunched free electron laser. A technique for the simulation of time dependent free electron lasers (FEL) to model the slippage effects is introduced, and the slowly varying envelope approximation in both z and t is used to illustrate the temporal behaviour in the prebunched FEL. Slippage effect on prebunched two-beam FEL is compared with the one-beam modeling. The evaluation of the radiation pulse energy, thermal and phase distribution, and radiation pulse shape in one-beam and two-beam modeling is studied. It was shown that the performance is considerably undermined when the slippage time is comparable to the pulse duration. However, prebunching reduces the slippage. Prebunching also leads to the radiation pulse with a single smooth spike.

Mirian, N. S., E-mail: najmeh.mirian@ipm.ir [School of Particle and Accelerator Physics, Institute for Research in Fundamental Sciences (IPM), Post code 19395-5531 Tehran (Iran, Islamic Republic of); Maraghechi, B. [Department of Physics, Amirkabir University of Technology, Post code 15875-4413 Tehran (Iran, Islamic Republic of)] [Department of Physics, Amirkabir University of Technology, Post code 15875-4413 Tehran (Iran, Islamic Republic of)

2014-04-15T23:59:59.000Z

138

MeV-Energy X Rays from Inverse Compton Scattering with Laser-Wakefield Accelerated Electrons  

Science Journals Connector (OSTI)

We report the generation of MeV x rays using an undulator and accelerator that are both driven by the same 100-terawatt laser system. The laser pulse driving the accelerator and the scattering laser pulse are independently optimized to generate a high energy electron beam (>200??MeV) and maximize the output x-ray brightness. The total x-ray photon number was measured to be ?1×107, the source size was 5???m, and the beam divergence angle was ?10??mrad. The x-ray photon energy, peaked at 1 MeV (reaching up to 4 MeV), exceeds the thresholds of fundamental nuclear processes (e.g., pair production and photodisintegration).

S. Chen; N. D. Powers; I. Ghebregziabher; C. M. Maharjan; C. Liu; G. Golovin; S. Banerjee; J. Zhang; N. Cunningham; A. Moorti; S. Clarke; S. Pozzi; D. P. Umstadter

2013-04-10T23:59:59.000Z

139

Observation of gain in a free-electron laser master oscillator-power amplifier  

SciTech Connect (OSTI)

We report the first operation of a master oscillator-power amplifier in which both devices are free-electron lasers. Gain optimization in the power amplifier was studied. A 35-A electron beam produced up to 60% gain at 3 {mu}m. The gain spectrum was obtained by gap tuning the power amplifier wiggler and evidence was found for violation of the Madey theorem due to high gain effects.

Vintro, L.; Benson, S.V.; Bhowmik, A.; Curtin, M.S.; Madey, J.M.J.; McMullin, W.A.; Richman, R.A. (Stanford Photon Research Laboratory, Stanford University, Stanford, California 94305 (USA) Rocketdyne Division, Rockwell International, 6633 Canoga Avenue, Canoga Park, California 91303 (USA))

1990-04-02T23:59:59.000Z

140

Soft-x-ray laser interferometry of a pinch discharge using a tabletop laser C. H. Moreno,* M. C. Marconi,* K. Kanizay, and J. J. Rocca  

E-Print Network [OSTI]

Soft-x-ray laser interferometry of a pinch discharge using a tabletop laser C. H. Moreno,* M. C Street, Kharkov 310002, Ukraine Received 18 December 1998 We have used a tabletop soft-x-ray laser region of the discharge. This demonstration of the use of tabletop soft-x-ray laser in plasma

Rocca, Jorge J.

Note: This page contains sample records for the topic "x-ray free-electron laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

A convenient alignment approach for x-ray imaging experiments based on laser positioning devices  

SciTech Connect (OSTI)

This study presents a two-laser alignment approach for facilitating the precise alignment of various imaging and measuring components with respect to the x-ray beam. The first laser constantly pointed to the output window of the source, in a direction parallel to the path along which the components are placed. The second laser beam, originating from the opposite direction, was calibrated to coincide with the first laser beam. Thus, a visible indicator of the direction of the incident x-ray beam was established, and the various components could then be aligned conveniently and accurately with its help.

Zhang Da; Donovan, Molly; Wu Xizeng; Liu Hong [Center for Bioengineering and School of Electrical and Computer Engineering, University of Oklahoma, Norman, Oklahoma 73019 (United States); Department of Radiology, University of Alabama at Birmingham, Birmingham, Alabama 35233 (United States); Center for Bioengineering and School of Electrical and Computer Engineering, University of Oklahoma, Norman, Oklahoma 73019 (United States)

2008-11-15T23:59:59.000Z

142

Analysis of saturation phenomena in Cerenkov free-electron lasers with a planar waveguide  

SciTech Connect (OSTI)

In this paper, the operation of the stimulated emission in Cerenkov free-electron laser (CFEL) is studied on the basis of the modulations of electron velocity and density by the electromagnetic (EM) field. The influence of the electron relaxation, due to mutual electrons collisions, on the electron dynamics is taken into account. We investigate the growth characteristics of Cerenkov laser operating in the small-signal and saturation regimes. In the saturation regime, the effect of velocity reduction of the electron beam on the gain dynamics is demonstrated. We also show that our results match with those of other well-known treatments in the small-signal gain limit.

Fares, Hesham; Yamada, Minoru [Division of Electrical Engineering and Computer Science, Kanazawa University, Kakuma-machi, Kanazawa, Ishikawa 920-1192 (Japan)

2011-09-15T23:59:59.000Z

143

INEX modeling of the Boeing ring optical resonator free electron laser  

Science Journals Connector (OSTI)

We present new results from the integrated numerical model of the accelerator/beam transport system and ring optical resonator of the Boeing free electron laser experiment. Modifications of the electron-beam transport have been included in a previously developed PARMELA model and are shown to reduce dramatically emittance growth in the 180° bend. The new numerically generated electron beam is used in the 3D FEL simulation code FELEX to calculate expected laser characteristics with the ring optical resonator and the 5 m untapered THUNDER wiggler. Performance sensitivity to optical cavity misalignments is studied.

J.C. Goldstein; R.L. Tokar; B.D. McVey; C.J. Elliott; D.H. Dowell; M.L. Laucks; A.R. Lowrey

1991-01-01T23:59:59.000Z

144

Structured x-ray beams from twisted electrons by inverse Compton scattering of laser light  

E-Print Network [OSTI]

The inverse Compton scattering of laser light on high-energetic twisted electrons is investigated with the aim to construct spatially structured x-ray beams. In particular, we analyze how the properties of the twisted electrons, such as the topological charge and aperture angle of the electron Bessel beam, affects the energy and angular distribution of scattered x-rays. We show that with suitably chosen initial twisted electron states one can synthesize tailor-made x-ray beam profiles with a well-defined spatial structure, in a way not possible with ordinary plane-wave electron beams.

Seipt, D; Fritzsche, S

2014-01-01T23:59:59.000Z

145

X-Ray Entangled Photon Production in Collisions of Laser Beams with Relativistic Ions  

E-Print Network [OSTI]

A method is suggested to produce, with the help of colliding laser photons with bunches of relativistic ions having two energy levels, both intense beams of monochromatic polarized X-ray fluorescence photons and significant number of X-ray entangled photons, via double Doppler transformation. Nonlinear susceptibility of the ions, the cross section and the rate of production of such photons at RHIC are estimated. Such beams of X-ray photons can be detected and applied to solve various problems, in a manner similar to the usage of optical photons.

K. A. Ispirian; M. K. Ispiryan

2010-04-02T23:59:59.000Z

146

Initial source of microbunching instability studies in a free electron laser injector  

SciTech Connect (OSTI)

We present the first experimental studies of the initial source of electron beam microbunching instability in a free electron laser (FEL) injector. By utilizing for the studies a transform-limited laser pulse at the photocathode, we eliminated laser-induced microbunching at the National Synchrotron Light Source Source Development Laboratory (SDL). The detailed measurements of the resulting electron beam led us to conclude that, at SDL, microbunching arising from shot noise is not amplified to any significant level, thereby allowing us to set an upper limit on the initial modulation depth of microbunching arising from shot noise. Our analysis demonstrated that the only significant source of microbunching instability under normal operational conditions at SDL is the longitudinal modulation of the photocathode laser pulse. Our work shows that assuring a longitudinally smoothed photocathode laser pulse allows mitigating microbunching instability at a typical FEL injector with a moderate microbunching gain.

Seletskiy, S.; Hidaka, Y; Murphy, J.B.; Podobedov, B.; Qian, H.; Shen, Y.; Wang, X.J.; Yang, X

2011-11-16T23:59:59.000Z

147

Toward the development of a soft x-ray reflection imaging microscope in the Schwarzschild configuration using a soft x-ray laser at 18. 2 nm  

SciTech Connect (OSTI)

We present the recent results obtained from a soft X-ray reflection imaging microscope in the Schwarzschild configuration. The microscope demonstrated a spatial resolution of 0.7 {mu}m with a magnification of 16 at 18.2 nm. The soft X-ray laser at 18.2 nm was used as an X-ray source. Mo/Si multilayers were coated on the Schwarzschild optics and the normal incidence reflectivity at 18.2 nm per surface was measured to be {approximately} 20 %. 18 refs., 6 figs.

Dicicco, D.; Rosser, R. (Princeton X-Ray Laser, Inc., Monmouth Junction, NJ (United States)); Kim, D.; Suckewer, S. (Princeton Univ., NJ (United States). Plasma Physics Lab.)

1991-12-01T23:59:59.000Z

148

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

E-Print Network [OSTI]

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

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

2014-01-01T23:59:59.000Z

149

Traveling wave pumping of ultra-short pulse x-ray lasers  

SciTech Connect (OSTI)

Pumping of proposed inner-shell photo-ionized (ISPI) x-ray lasers places stringent requirements on the optical pump source. We investigate these requirements for an example x-ray laser (XRL) in Carbon lasing on the 2p-1s transition at 45 A. Competing with this lasing transition is the very fast Auger decay rate out of the upper lasing state, such that the x-ray laser would self-terminate on a femto- second time scale. XRL gain may be demonstrated if pump energy is delivered in a time short when compared to the Auger rate. The fast self-termination also demands that we sequentially pump the length of the x-ray laser at the group velocity of the x-ray laser. This is the classical traveling wave requirement. It imposes a condition on the pumping source that the phase angle of the pump laser be precisely de- coupled from the pulse front angle. At high light intensities, this must be performed with a vacuum grating delay line. We will also include a discussion of issues related to pump energy delivery, i.e. pulse-front curvature, temporal blurring and puke fidelity. An all- reflective optical system with low aberration is investigated to see if it fulfills the requirements. It is expected that these designs together with new high energy (>1J) ultra-short pulse (< 40 fs) pump lasers now under construction may fulfill our pump energy conditions and produce a tabletop x-ray laser.

Snavely, R.A.; Da Silva, L.B.; Eder, D.C.; Matthews, D.L.; Moon, S.J.

1997-11-10T23:59:59.000Z

150

Resonantly photo-pumped nickel-like erbium X-ray laser  

DOE Patents [OSTI]

A resonantly photo-pumped X-ray laser (10) that enhances the gain of seve laser lines that also lase because of collisional excitations and recombination processes, is described. The laser comprises an aluminum (12) and erbium (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 erbium ions (34) are resonantly photo-pumped by line emission from hydrogen-like aluminum ions (32).

Nilsen, Joseph (Livermore, CA)

1990-01-01T23:59:59.000Z

151

Overview of the program on soft x-ray lasers and their applications at Princeton  

SciTech Connect (OSTI)

In the last several years, rapid progress in the development of soft x-ray lasers (SXL) has been observed at a number of laboratories worldwide. Although SXLs are very young'' devices they have already been used for microscopy and holography, and new ideas emerging for broader application of SXLs to microscopy, holography and lithography. This paper describes the work at Princeton University on the development of a soft x-ray imaging transmission microscopy using a SXL as a radiation source and work on the development of a novel soft x-ray reflection microscope and its application to biological cell studies and lithography. Progress in the development of a photopumped VUV laser (60 nm), and programs for the development of a small scale SXL and for the application of a powerful subpicosecond KrF laser system are also discussed. 35 refs., 9 figs., 1 tab.

Suckewer, S.; Ilcisin, K. (Princeton Univ., NJ (USA). Plasma Physics Lab. Princeton Univ., NJ (USA). Dept. of Mechanical and Aerospace Engineering)

1991-05-01T23:59:59.000Z

152

Stability properties of free-electron laser in Raman regime with thermal electron beam  

SciTech Connect (OSTI)

In the context of kinetic theory an expression for the growth rate of a free-electron laser, under the weak resonance instability condition, for full dispersion relation has been obtained. The space-charge potential is included in the analysis and the expression for growth rate reduces to that of the Compton regime under the low density condition. With the assumption of a spread in the longitudinal momentum in the form of a Gaussian distribution function, the effect of the thermal electron beam on the growth rate is studied. The results are compared to another linear theory, a computer simulation, and an experiment.

Chakhmachi, A. [Plasma Physics and Nuclear Fusion Research School, Nuclear Science and Technology Research Institute, Atomic Energy Organization of Iran, P.O. Box 14155-1339, Tehran (Iran, Islamic Republic of); Department of Physics, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of); Maraghechi, B. [Department of Physics, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of)

2009-04-15T23:59:59.000Z

153

Transverse-Coherence Properties of the Free-Electron-Laser FLASH at DESY  

SciTech Connect (OSTI)

A general theoretical approach based on the decomposition of statistical fields into a sum of independently propagating transverse modes was used for the analysis of the coherence properties of the new free-electron laser source FLASH operated at 13.7 nm wavelength. The analysis shows that several transverse modes are contributing to the total radiation field of FLASH. The results of theoretical calculations are compared with measurements using Young's double-slit experiment. The coherence lengths in the horizontal and in the vertical directions 20 m downstream from the source are estimated at 300 and 250 {mu}m, respectively.

Singer, A.; Vartanyants, I. A.; Kuhlmann, M.; Duesterer, S.; Treusch, R.; Feldhaus, J. [HASYLAB at DESY, Notkestrasse 85, D-22607 Hamburg (Germany)

2008-12-19T23:59:59.000Z

154

Overview of the ARGOS X-ray framing camera for Laser MegaJoule  

SciTech Connect (OSTI)

Commissariat à l’Énergie Atomique et aux Énergies Alternatives has developed the ARGOS X-ray framing camera to perform two-dimensional, high-timing resolution imaging of an imploding target on the French high-power laser facility Laser MegaJoule. The main features of this camera are: a microchannel plate gated X-ray detector, a spring-loaded CCD camera that maintains proximity focus in any orientation, and electronics packages that provide remotely-selectable high-voltages to modify the exposure-time of the camera. These components are integrated into an “air-box” that protects them from the harsh environmental conditions. A miniaturized X-ray generator is also part of the device for in situ self-testing purposes.

Trosseille, C., E-mail: clement.trosseille@cea.fr; Aubert, D.; Auger, L.; Bazzoli, S.; Brunel, P.; Burillo, M.; Chollet, C.; Jasmin, S.; Maruenda, P.; Moreau, I.; Oudot, G.; Raimbourg, J.; Soullié, G.; Stemmler, P.; Zuber, C. [CEA, DAM, DIF, F-91297 Arpajon (France); Beck, T. [CEA, DEN, CADARACHE, F-13108 St Paul lez Durance (France); Gazave, J. [CEA, DAM, CESTA, F-33116 Le Barp (France)

2014-11-15T23:59:59.000Z

155

Compact tunable Compton x-ray source from laser-plasma accelerator and plasma mirror  

E-Print Network [OSTI]

We present results of the first tunable Compton backscattering (CBS) x-ray source that is based on the easily aligned combination of a laser-plasma accelerator (LPA) and a plasma mirror (PM). The LPA is driven in the blowout regime by 30 TW, 30 fs laser pulses, and produces high-quality, tunable, quasi-monoenergetic electron beams. A thin plastic film near the gas jet exit efficiently retro-reflects the LPA driving pulse with relativistic intensity into oncoming electrons to produce $2\\times10^{7}$ CBS x-ray photons per shot with 10-20 mrad angular divergence and 50 % (FWHM) energy spread without detectable bremsstrahlung background. The x-ray central energy is tuned from 75 KeV to 200 KeV by tuning the LPA e-beam central energy. Particle-in-cell simulations of the LPA, the drive pulse/PM interaction and CBS agree well with measurements.

Tsai, Hai-En; Shaw, Joseph; Li, Zhengyan; Arefiev, Alexey V; Zhang, Xi; Zgadzaj, Rafal; Henderson, Watson; Khudik, V; Shvets, G; Downer, M C

2014-01-01T23:59:59.000Z

156

Influence of space charge wave on quasilinear theory of the free-electron laser saturation  

SciTech Connect (OSTI)

A quasilinear theory is presented that describes the self-consistent evolution of the electron beam distribution function and fields in a free-electron laser when the space charge wave is present. In the Raman regime, a high-density electron beam has an appreciable space charge potential. A broad spectrum of waves is assumed in order to have a relatively wide range of resonant particles. A one-dimensional helical magnetic field is considered and the analysis is based on the Vlasov-Maxwell equations. Two coupled differential equations are derived, which, in conjunction with conservation laws, describe the quasilinear development by the diffusion of electrons in the momentum space. This leads to the saturation of the free-electron laser instability by the plateau formation. Analytical expressions for the growth rate and for the diffusion coefficient are derived, which reduced to those in the Compton regime under appropriate conditions. By use of the linear growth rate and diffusion coefficient, an analytical expression for efficiency in Raman regime was derived. A numerical analysis is conducted to study the effects of the spectral width of radiation and the thermal spread of the electron beam on the efficiency.

Chakhmachi, A. [Plasma Physics and Nuclear Fusion Research School, Nuclear Science and Technology Research Institute, Atomic Energy Organization of Iran, P.O. Box 14155-1339, Tehran (Iran, Islamic Republic of); Department of Physics, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of); Maraghechi, B. [Department of Physics, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of)

2009-07-15T23:59:59.000Z

157

Multi-range free-electron laser with a pair of dielectric multilayer mirrors  

SciTech Connect (OSTI)

We report the experimental achievement of a free-electron laser in three wavelength regions, mid-infrared, near-infrared, and visible, using a pair of dielectric multilayer mirrors in the storage ring NIJI-IV. Dielectric multilayer mirrors can have high reflectivity at wavelength regions corresponding to higher-diffraction orders of the target wavelength. A narrowing of the relative bandwidth of the dielectric multilayer mirrors was observed in the higher-diffraction orders of the target wavelength and was found to be caused by high diffraction and carbon contamination. Our experimental results will be applied to development of a multi-rang laser that have a gain in a wade wavelength region.

Sei, Norihiro; Ogawa, Hiroshi; Yamada, Kawakatsu [Research Institute of Instrumentation Frontier, National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan)

2012-10-01T23:59:59.000Z

158

Soft x-ray images of the laser entrance hole of ignition hohlraums  

SciTech Connect (OSTI)

Hohlraums are employed at the national ignition facility to convert laser energy into a thermal x-radiation drive, which implodes a fusion capsule, thus compressing the fuel. The x-radiation drive is measured with a low spectral resolution, time-resolved x-ray spectrometer, which views the region around the hohlraum's laser entrance hole. This measurement has no spatial resolution. To convert this to the drive inside the hohlraum, the size of the hohlraum's opening ('clear aperture') and fraction of the measured x-radiation, which comes from this opening, must be known. The size of the clear aperture is measured with the time integrated static x-ray imager (SXI). A soft x-ray imaging channel has been added to the SXI to measure the fraction of x-radiation emitted from inside the clear aperture. A multilayer mirror plus filter selects an x-ray band centered at 870 eV, near the peak of the x-ray spectrum of a 300 eV blackbody. Results from this channel and corrections to the x-radiation drive are discussed.

Schneider, M. B.; Meezan, N. B.; Alvarez, S. S.; Alameda, J.; Baker, S.; Bell, P. M.; Bradley, D. K.; Callahan, D. A.; Celeste, J. R.; Dewald, E. L.; Dixit, S. N.; Doeppner, T.; Eder, D. C.; Edwards, M. J.; Fernandez-Perea, M.; Hau-Riege, S.; Hsing, W.; Izumi, N.; Jones, O. S.; Kalantar, D. H. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551-0808 (United States); and others

2012-10-15T23:59:59.000Z

159

Single mimivirus particles intercepted and imaged with an X-ray laser (CXIDB ID 1)  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

These are the files used to reconstruct the images in the paper "Single Mimivirus particles intercepted and imaged with an X-ray laser". Besides the diffracted intensities, the Hawk configuration files used for the reconstructions are also provided. The files from CXIDB ID 1 are the pattern and configuration files for the pattern showed in Figure 2a in the paper.

Seibert, M. Marvin; Ekeberg, Tomas; Maia, Filipe R.N.C.

160

Single mimivirus particles intercepted and imaged with an X-ray laser (CXIDB ID 2)  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

These are the files used to reconstruct the images in the paper "Single Mimivirus particles intercepted and imaged with an X-ray laser". Besides the diffracted intensities, the Hawk configuration files used for the reconstructions are also provided. The files from CXIDB ID 2 are the pattern and configuration files for the pattern showed in Figure 2b in the paper.

Seibert, M. Marvin; Ekeberg, Tomas

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161

High-throughput imaging of heterogeneous cell organelles with an X-ray laser  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

Preprocessed detector images that were used for the paper "High-throughput imaging of heterogeneous cell organelles with an X-ray laser". The CXI file contains the entire recorded data - including both hits and blanks. It also includes down-sampled images and LCLS machine parameters. Additionally, the Cheetah configuration file is attached that was used to create the pre-processed data.

Hantke, Max, F.

162

Pump pulse-width dependence of grazing-incidence pumped transient collisional soft-x-ray lasers M. Berrill,1  

E-Print Network [OSTI]

Pump pulse-width dependence of grazing-incidence pumped transient collisional soft-x-ray lasers M 2007 The output energy dependence of high repetition rate grazing incidence pumped Ni-like Mo, Ni-like Ag, and Ne-like Ti transient collisional soft x-ray lasers on the duration of the pump pulse

Rocca, Jorge J.

163

Observation and modelling of hollow multicharged ion x-ray spectra radiated by laser produced plasma  

SciTech Connect (OSTI)

The role of the highly charged hollow ions in the X-Ray emission plasma spectTa is investigated for 2 cases: (1) plasma obtained under inadiation of Ar clusters by ultrashort laser pulses and (2) Mg-plasma heated by a short-wavelength long (nanosecond) laser pulse. Experimental measurements are presented. Calculations in support of these measurements have been performed using a detailed atomic kinetics model with the ion distributions found from solution of the time-dependent rate equations.

Colgan, James P [Los Alamos National Laboratory; Abdallah, Joseph [Los Alamos National Laboratory; Faenov, A Ya [JAPAN/RUSSIA; Pikuz, T A [JAPAN/RUSSIA; Akobelev, I Yu [JAPAN/RUSSIA; Fukuda, Y [JAPAN/RUSSIA

2008-01-01T23:59:59.000Z

164

A high quality permanent-magnet wiggler for the Rocketdyne/Stanford infrared free electron laser  

Science Journals Connector (OSTI)

A high quality, variable gap, variable taper, permanent-magnet wiggler has been built for infrared free electron laser (FEL) experiments to be performed at the Stanford Photon Research Laboratory. The design and characterization procedure used to assemble the wiggler is discussed. A simulated annealing code was used to minimize field errors arising from variations in the individual magnets. The computed electron trajectories associated with the measured magnetic fields are presented for a range of different operating points of the wiggler. These plots indicate a very high quality field over a large range of different wiggler operating regimes. Resultant trajectory wander over the 2 m long wiggler for a 40 MeV electron at a wiggler gap corresponding to 3.3 kG was calculated to be less than 25 ?m. The ability to control trajectory wander and optical phase slip using the simulated annealing code suggests future extensions to extremely long wigglers.

Mark S. Curtin; Anup Bhowmik; Wayne A. McMullin; Stephen V. Benson; John M.J. Madey; Bruce A. Richman; Louis Vintro

1988-01-01T23:59:59.000Z

165

Dissociative multiple ionization of diatomic molecules by extreme-ultraviolet free-electron-laser pulses  

SciTech Connect (OSTI)

Nuclear dynamics in dissociative multiple ionization processes of diatomic molecules exposed to extreme-ultraviolet free-electron-laser pulses is studied theoretically using the Monte Carlo wave packet approach. By simulated detection of the emitted electrons, the model reduces a full propagation of the system to propagations of the nuclear wave packet in one specific electronic charge state at a time. Suggested ionization channels can be examined, and kinetic energy release spectra for the nuclei can be calculated and compared with experiments. Double ionization of O{sub 2} is studied as an example, and good agreement with published experimental data is obtained by simulating the dynamics on ten different electronic Born-Oppenheimer curves.

Leth, Henriette Astrup; Madsen, Lars Bojer [Lundbeck Foundation Theoretical Center for Quantum System Research, Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark)

2011-06-15T23:59:59.000Z

166

Optical measurements on the Boeing free electron laser ring resonator experiment  

Science Journals Connector (OSTI)

The Boeing free electron laser is presently operating with a stable semiconfocal ring optical cavity surrounding a 5 m wiggler. The resonator consists of two grazing-incidence reflective telescopes each formed by a grazing-incidence hyperboloid and its companion off-axis paraboloid. The resonator is closed by two flats: one used for dynamic jitter correction and the other used to outcouple some of the circulating beam. It is critical to lasing that the alignment of the resonator be maintained, the focus of the optical mode be at the midpoint of the wiggler, and the wavefront quality of the propagating beam be maintained. Measurements of the focus position, power loss, and wavefront quality are made before operation of the electron accelerator to diagnose whether the conditions required for lasing exist.

M.L. Laucks; D.H. Dowell; A.R. Lowrey; M. Bemes; A. Currie; P. Johnson; K. McCrary; J. Adamski; D. Pistoresi; D.R. Shoffstall; M. Bentz; R. Burns; R. Hudyma; K. Sun; W. Mower; S. Bender; J. Goldstein; A. Lumpkin; B. McVey; R. Tokar; D. Shemwell

1991-01-01T23:59:59.000Z

167

A Far-infrared Undulator for Coherent Synchrotron Radiation and Free Electron Laser at Tohoku University  

SciTech Connect (OSTI)

In order to develop an intense far-infrared radiation source, a high quality electron beam has been studied at Tohoku University, Sendai. The bunch length of the beam expected is very much shorter than terahertz (THz) wavelength, so that coherent spontaneous emission of synchrotron radiation will be a promising high brilliant far-infrared source. An undulator consisting of permanent magnets has been designed in which optional free electron laser (FEL) will be operated in free space mode. Consequently the minimum gap of the undulator is decided to be 54 mm for 0.36 mm radiation to avoid diffraction loss, and then the period length of 10 cm is employed. The undulator may cover a wavelength range from 0.18 to 0.36 mm with the beam energy of 17 MeV. Property of coherent THz radiation from the undulator and possibility of novel pre-bunched THz FEL is discussed.

Hama, Hiroyuki; Hinode, Fujio; Kawai, Masayuki; Nanbu, Kenichi; Miyahara, Fusashi; Yasuda, Mafuyu [Laboratory of Nuclear Science, Tohoku University School of Science, 1-2-1 Mikamine, Taihaku-ku, Sendai 982-0826 (Japan)

2010-06-23T23:59:59.000Z

168

Acceleration of electrons using an inverse free electron laser auto- accelerator  

SciTech Connect (OSTI)

We present data from our study of a device known as the inverse free electron laser. First, numerical simulations were performed to optimize the design parameters for an experiment that accelerates electrons in the presence of an undulator by stimulated absorption of radiation. The Columbia free electron laser (FEL) was configured as an auto-accelerator (IFELA) system; high power (MW's) FEL radiation at {approximately}1.65 mm is developed along the first section of an undulator inside a quasi-optical resonator. The electron beam then traverses a second section of undulator where a fraction of the electrons is accelerated by stimulated absorption of the 1.65 mm wavelength power developed in the first undulator section. The second undulator section has very low gain and does not generate power on its own. We have found that as much as 60% of the power generated in the first section can be absorbed in the second section, providing that the initial electron energy is chosen correctly with respect to the parameters chosen for the first and second undulators. An electron momentum spectrometer is used to monitor the distribution of electron energies as the electrons exit the IFELA. We have found; using our experimental parameters, that roughly 10% of the electrons are accelerated to energies as high as 1100 keV, in accordance with predictions from the numerical model. The appearance of high energy electrons is correlated with the abrupt absorption of millimeter power. The autoaccelerator configuration is used because there is no intense source of coherent power at the 1.65 mm design wavelength other than the FEL.

Wernick, I.K.; Marshall, T.C.

1992-07-01T23:59:59.000Z

169

Acceleration of electrons using an inverse free electron laser auto- accelerator  

SciTech Connect (OSTI)

We present data from our study of a device known as the inverse free electron laser. First, numerical simulations were performed to optimize the design parameters for an experiment that accelerates electrons in the presence of an undulator by stimulated absorption of radiation. The Columbia free electron laser (FEL) was configured as an auto-accelerator (IFELA) system; high power (MW`s) FEL radiation at {approximately}1.65 mm is developed along the first section of an undulator inside a quasi-optical resonator. The electron beam then traverses a second section of undulator where a fraction of the electrons is accelerated by stimulated absorption of the 1.65 mm wavelength power developed in the first undulator section. The second undulator section has very low gain and does not generate power on its own. We have found that as much as 60% of the power generated in the first section can be absorbed in the second section, providing that the initial electron energy is chosen correctly with respect to the parameters chosen for the first and second undulators. An electron momentum spectrometer is used to monitor the distribution of electron energies as the electrons exit the IFELA. We have found; using our experimental parameters, that roughly 10% of the electrons are accelerated to energies as high as 1100 keV, in accordance with predictions from the numerical model. The appearance of high energy electrons is correlated with the abrupt absorption of millimeter power. The autoaccelerator configuration is used because there is no intense source of coherent power at the 1.65 mm design wavelength other than the FEL.

Wernick, I.K.; Marshall, T.C.

1992-07-01T23:59:59.000Z

170

Lensless X-Ray Imaging in Reflection  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Lensless X-Ray Imaging in Lensless X-Ray Imaging in Reflection Lensless X-Ray Imaging in Reflection Print Wednesday, 26 October 2011 00:00 The advent of x-ray free-electron laser (XFEL) light sources has led to an outburst of research activities in the field of lensless imaging. XFELs combine the advantages of sychrotron light sources (high brightness and x-ray wavelengths relevant to atomic and molecular phenomena) with the advantages of visible-light lasers (highly coherent beams). All of these characteristics are important for coherent x-ray diffraction imaging-lensless imaging techniques that are proving to be integral to single-shot, high-resolution imaging of both complex materials and biological samples. Existing techniques are typically designed for transmission geometry, however, and use isolated objects, requiring special sample fabrication and restricting the type of samples under investigation. Recently, researchers from the ALS and the University of Oregon have shown at ALS Beamline 12.0.2 that it is possible to form x-ray holograms in reflection geometry by using the light scattered from a sample, opening the door to lensless imaging of a wealth of new material samples.

171

PUBLISHED ONLINE: 17 JANUARY 2010 | DOI: 10.1038/NPHYS1506 High-reflectivity high-resolution X-ray crystal  

E-Print Network [OSTI]

of X-ray free-electron laser oscillators (XFELOs), next-generation hard-X-ray sources of the highest-resolution X-ray crystal optics with diamonds Yuri V. Shvyd'ko1 *, Stanislav Stoupin1 , Alessandro Cunsolo1,2 , Ayman H. Said1 and Xianrong Huang2 Owing to the depth to which hard X-rays penetrate into most materials

Loss, Daniel

172

Effects of delay time on transient Ni-like x-ray lasers  

Science Journals Connector (OSTI)

In transient collisional excitation scheme, a long (nanosecond) prepulse is used to perform and ionize plasmas. After a delay time, a short (sub- or picosecond) intense laser pulse is used to rapidly heat the plasma. This results in transient x-ray lasers with high gain. Effects of delay time on transient collisional excitation nickel-like x-ray lasers are investigated analytically using a simple model. The calculations show that the longer delay time can greatly relax the density gradient. This is very critical for the propagation of x-ray lasers. However, a too long delay will reduce the electron temperature of the plasma before the arrival of the short pulse. Increasing the intensity of the long pulse or extending the pulse duration can keep the temperature required to maintain a high percentage of Ni-like ions while the delay time is longer. Similarly, increasing the intensity of the short pulse or extending the duration can also raise the electron temperature, resulting in higher gain coefficient. Our results indicate that extending the pulse duration is more efficient than that of increasing the intensity.

Y. J. Li, X. Lu, and J. Zhang

2002-10-30T23:59:59.000Z

173

Model for electron cooling by radiation losses in plasmas: application to soft x-ray laser development  

SciTech Connect (OSTI)

We present a simple model which may be used to evaluate the suitability of different ions for rapid plasma cooling by line radiation in recombination pumped x-ray laser schemes.

Skinner, C.H.; Keane, C.

1986-02-01T23:59:59.000Z

174

Lensless X-Ray Imaging in Reflection  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

X-Ray Imaging in Reflection Print X-Ray Imaging in Reflection Print The advent of x-ray free-electron laser (XFEL) light sources has led to an outburst of research activities in the field of lensless imaging. XFELs combine the advantages of sychrotron light sources (high brightness and x-ray wavelengths relevant to atomic and molecular phenomena) with the advantages of visible-light lasers (highly coherent beams). All of these characteristics are important for coherent x-ray diffraction imaging-lensless imaging techniques that are proving to be integral to single-shot, high-resolution imaging of both complex materials and biological samples. Existing techniques are typically designed for transmission geometry, however, and use isolated objects, requiring special sample fabrication and restricting the type of samples under investigation. Recently, researchers from the ALS and the University of Oregon have shown at ALS Beamline 12.0.2 that it is possible to form x-ray holograms in reflection geometry by using the light scattered from a sample, opening the door to lensless imaging of a wealth of new material samples.

175

Lensless X-Ray Imaging in Reflection  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

X-Ray Imaging in Reflection Print X-Ray Imaging in Reflection Print The advent of x-ray free-electron laser (XFEL) light sources has led to an outburst of research activities in the field of lensless imaging. XFELs combine the advantages of sychrotron light sources (high brightness and x-ray wavelengths relevant to atomic and molecular phenomena) with the advantages of visible-light lasers (highly coherent beams). All of these characteristics are important for coherent x-ray diffraction imaging-lensless imaging techniques that are proving to be integral to single-shot, high-resolution imaging of both complex materials and biological samples. Existing techniques are typically designed for transmission geometry, however, and use isolated objects, requiring special sample fabrication and restricting the type of samples under investigation. Recently, researchers from the ALS and the University of Oregon have shown at ALS Beamline 12.0.2 that it is possible to form x-ray holograms in reflection geometry by using the light scattered from a sample, opening the door to lensless imaging of a wealth of new material samples.

176

Lensless X-Ray Imaging in Reflection  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Lensless X-Ray Imaging in Reflection Print Lensless X-Ray Imaging in Reflection Print The advent of x-ray free-electron laser (XFEL) light sources has led to an outburst of research activities in the field of lensless imaging. XFELs combine the advantages of sychrotron light sources (high brightness and x-ray wavelengths relevant to atomic and molecular phenomena) with the advantages of visible-light lasers (highly coherent beams). All of these characteristics are important for coherent x-ray diffraction imaging-lensless imaging techniques that are proving to be integral to single-shot, high-resolution imaging of both complex materials and biological samples. Existing techniques are typically designed for transmission geometry, however, and use isolated objects, requiring special sample fabrication and restricting the type of samples under investigation. Recently, researchers from the ALS and the University of Oregon have shown at ALS Beamline 12.0.2 that it is possible to form x-ray holograms in reflection geometry by using the light scattered from a sample, opening the door to lensless imaging of a wealth of new material samples.

177

Lensless X-Ray Imaging in Reflection  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Lensless X-Ray Imaging in Reflection Print Lensless X-Ray Imaging in Reflection Print The advent of x-ray free-electron laser (XFEL) light sources has led to an outburst of research activities in the field of lensless imaging. XFELs combine the advantages of sychrotron light sources (high brightness and x-ray wavelengths relevant to atomic and molecular phenomena) with the advantages of visible-light lasers (highly coherent beams). All of these characteristics are important for coherent x-ray diffraction imaging-lensless imaging techniques that are proving to be integral to single-shot, high-resolution imaging of both complex materials and biological samples. Existing techniques are typically designed for transmission geometry, however, and use isolated objects, requiring special sample fabrication and restricting the type of samples under investigation. Recently, researchers from the ALS and the University of Oregon have shown at ALS Beamline 12.0.2 that it is possible to form x-ray holograms in reflection geometry by using the light scattered from a sample, opening the door to lensless imaging of a wealth of new material samples.

178

Breakthrough: X-ray Laser Captures Atoms and Molecules in Action  

SciTech Connect (OSTI)

The Linac Coherent Light Source at SLAC is the world's most powerful X-ray laser. Just two years after turning on in 2009, breakthrough science is emerging from the LCLS at a rapid pace. A recent experiment used the X-rays to create and probe a 2-million-degree piece of matter in a controlled way for the first time-a significant leap toward understanding the extreme conditions found in the hearts of stars and giant planets, and a finding which could further guide research into nuclear fusion, the mechanism that powers the sun. Upcoming experiments will investigate the fundamental, atomic-scale processes behind such phenomena as superconductivity and magnetism, as well as peering into the molecular workings of photosynthesis in plants.

Bergmann, Uwe

2012-04-26T23:59:59.000Z

179

Breakthrough: X-ray Laser Captures Atoms and Molecules in Action  

ScienceCinema (OSTI)

The Linac Coherent Light Source at SLAC is the world's most powerful X-ray laser. Just two years after turning on in 2009, breakthrough science is emerging from the LCLS at a rapid pace. A recent experiment used the X-rays to create and probe a 2-million-degree piece of matter in a controlled way for the first time-a significant leap toward understanding the extreme conditions found in the hearts of stars and giant planets, and a finding which could further guide research into nuclear fusion, the mechanism that powers the sun. Upcoming experiments will investigate the fundamental, atomic-scale processes behind such phenomena as superconductivity and magnetism, as well as peering into the molecular workings of photosynthesis in plants.

Bergmann, Uwe

2014-05-21T23:59:59.000Z

180

Efficiency enhancement in a single-pass Raman free electron laser  

SciTech Connect (OSTI)

Efficiency enhancement in free electron laser (FEL) with ion channel and axial magnetic field is compared. By using Maxwell's equations and nonwiggler averaged equation of motion of electron beam, a set of coupled nonlinear differential equations is derived in the slowly varying amplitude and wave number approximation. Because of using nonwiggler averaged equation of motion, it is possible to treat the injection of the beam into the wiggler. The electron beam propagates with a relativistic velocity, ions are assumed immobile and slippage is ignored. The final set of nonlinear first-order differential equations describing the nonlinear evolution of the FEL is solved by the Runge-Kutta method. Efficiency enhancement in group I orbits is almost the same for both ion channel and axial magnetic field cases, with somewhat larger growth rate for the latter. In group II orbits, efficiency enhancement is not possible for the ion-channel guiding; however, the intrinsic efficiency can be larger than that of the axial magnetic field case.

Rouhani, M. H.; Maraghechi, B. [Department of Physics, Amirkabir University of Technology, 15875-4413 Tehran (Iran, Islamic Republic of)

2009-09-15T23:59:59.000Z

Note: This page contains sample records for the topic "x-ray free-electron laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Tests of a grazing-incidence ring resonator free-electron laser  

SciTech Connect (OSTI)

This paper reports on the Boeing free-electron laser (FEL) optical cavity that has been changed from a simple concentric cavity using two spherical mirrors to a larger grazing-incidence ring resonator. The new resonator consists of two mirror telescopes located at each end of the wiggler with a round-trip path length of approximately 133 m. Each telescope is a grazing-incidence hyperboloid followed by a normal-incidence paraboloid. Initial tests showed that poorly positioned ring focus and unreliable pointing alignment resulted in reduced and structured FEL output. (First lasing operation occurred on March 23 and 24, 1990.) Later efforts concentrated on improving the resonator alignment techniques and lowering the single-pass losses. FEL performance and reliability have significantly improved due to better ring alignment. The alignment procedure and recent lasing results are described. The effect the electron beam has on lasing is also discussed. Measurements are presented showing how FEL temporal output and wavelength are sensitive to electron beam energy variations.

Dowell, D.H.; Laucks, M.L.; Lowrey, A.R.; Adamski, J.L.; Pistoresi, D.J.; Shoffstall, D.R. (Boeing Aerospace and Electronics, Seattle, WA (US)); Bentz, M.P.; Burns, R.H.; Guha, J.; Sun, K.; Tomita, W. (Rockwell International Corp., Canoga Park, CA (United States). Rocketdyne Div.); Lumpkin, A.H.; Bender, S.; Byrd, D.; Tokar, R.L. (Los Alamos National Lab., NM (United States))

1991-12-01T23:59:59.000Z

182

Soft x-ray laser holography with wavelength P. W. Wachulak, M. C. Marconi,* R. A. Bartels, C. S. Menoni, and J. J. Rocca  

E-Print Network [OSTI]

Soft x-ray laser holography with wavelength resolution P. W. Wachulak, M. C. Marconi,* R. A the tabletop acquisition of soft x-ray holographic images of nanostructures with a spatial resolution of 46 using a compact, tabletop capillary-discharge soft x-ray laser emitting at 46.9 nm in a high

Rocca, Jorge J.

183

An infrared free-electron laser for the Chemical Dynamics Research Laboratory. Design report  

SciTech Connect (OSTI)

This document describes a free-electron laser (FEL) proposed as part of the Chemical Dynamics Research Laboratory (CDRL), a user facility that also incorporates several advanced lasers of conventional design and two beamlines for the ALS. The FEL itself addresses the needs of the chemical sciences community for a high-brightness, tunable source covering a broad region of the infrared spectrum -- from 3 to 50 {mu}m. All of these sources, together with a variety of sophisticated experimental stations, will be housed in a new building to be located adjacent to the ALS. The radiation sources can be synchronized to permit powerful two-color, pump-probe experiments that will further our fundamental understanding of chemical dynamics at the molecular level, especially those aspects relevant to practical issues in combustion chemistry. The technical approach adopted in this design makes use of superconducting radiofrequency (SCRF) accelerating structures. The primary motivation for adopting this approach was to meet the user requirement for wavelength stability equal to one part in 10{sup 4}. Previous studies concluded that a wavelength stability of only one part in 10{sup 3} could be achieved with currently available room-temperature technology. In addition, the superconducting design operates in a continuous-wave (cw) mode and hence offers considerably higher average optical output power. It also allows for various pulse-gating configurations that will permit simultaneous multiuser operations. A summary of the comparative performance attainable with room-temperature and superconducting designs is given. The FEL described in this report provides a continuous train of 30-ps micropulses, with 100{mu}J of optical energy per micropulse, at a repetition rate of 6.1 MHz. The device can also deliver pulses at a cw repetition rate of 12.2 MHz, with a peak power of 50 {mu}J per micropulse. 70 ref.

Vaughan, D. [comp.

1992-04-01T23:59:59.000Z

184

An infrared free-electron laser for the Chemical Dynamics Research Laboratory  

SciTech Connect (OSTI)

This document describes a free-electron laser (FEL) proposed as part of the Chemical Dynamics Research Laboratory (CDRL), a user facility that also incorporates several advanced lasers of conventional design and two beamlines for the ALS. The FEL itself addresses the needs of the chemical sciences community for a high-brightness, tunable source covering a broad region of the infrared spectrum -- from 3 to 50 {mu}m. All of these sources, together with a variety of sophisticated experimental stations, will be housed in a new building to be located adjacent to the ALS. The radiation sources can be synchronized to permit powerful two-color, pump-probe experiments that will further our fundamental understanding of chemical dynamics at the molecular level, especially those aspects relevant to practical issues in combustion chemistry. The technical approach adopted in this design makes use of superconducting radiofrequency (SCRF) accelerating structures. The primary motivation for adopting this approach was to meet the user requirement for wavelength stability equal to one part in 10{sup 4}. Previous studies concluded that a wavelength stability of only one part in 10{sup 3} could be achieved with currently available room-temperature technology. In addition, the superconducting design operates in a continuous-wave (cw) mode and hence offers considerably higher average optical output power. It also allows for various pulse-gating configurations that will permit simultaneous multiuser operations. A summary of the comparative performance attainable with room-temperature and superconducting designs is given. The FEL described in this report provides a continuous train of 30-ps micropulses, with 100{mu}J of optical energy per micropulse, at a repetition rate of 6.1 MHz. The device can also deliver pulses at a cw repetition rate of 12.2 MHz, with a peak power of 50 {mu}J per micropulse. 70 ref.

Vaughan, D. (comp.)

1992-04-01T23:59:59.000Z

185

Incoherent x-ray scattering in single molecule imaging  

E-Print Network [OSTI]

Imaging of the structure of single proteins or other biomolecules with atomic resolution would be enormously beneficial to structural biology. X-ray free-electron lasers generate highly intense and ultrashort x-ray pulses, providing a route towards imaging of single molecules with atomic resolution. The information on molecular structure is encoded in the coherent x-ray scattering signal. In contrast to crystallography there are no Bragg reflections in single molecule imaging, which means the coherent scattering is not enhanced. Consequently, a background signal from incoherent scattering deteriorates the quality of the coherent scattering signal. This background signal cannot be easily eliminated because the spectrum of incoherently scattered photons cannot be resolved by usual scattering detectors. We present an ab initio study of incoherent x-ray scattering from individual carbon atoms, including the electronic radiation damage caused by a highly intense x-ray pulse. We find that the coherent scattering pa...

Slowik, Jan Malte; Dixit, Gopal; Jurek, Zoltan; Santra, Robin

2014-01-01T23:59:59.000Z

186

Ultra hard x rays from krypton clusters heated by intense laser fields R. C. Issac,a)  

E-Print Network [OSTI]

drives a fast ignition wave.15 Prop- erties of the cluster media as well as the incident laser paUltra hard x rays from krypton clusters heated by intense laser fields R. C. Issac,a) G. Vieux, B of ultrashort laser pulses with krypton clusters at intensity up to 1.3 1018 Wcm 2 has been investigated

Strathclyde, University of

187

Using Light to Control How X Rays Interact with Matter  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

ultrafast x-ray spectroscopy. ALS femtosecond spectroscopy beamline layout. Femtosecond x-ray and laser pulses derive from a single 800-nm laser oscillator. Femtosecond x rays...

188

In vivo crystallography at X-ray free-electron lasers: the next generation of structural biology?  

Science Journals Connector (OSTI)

...2-1 Yamadaoka, Suita, Osaka 565-0871, Japan 9 Japan Synchrotron Radiation Research Institute, , Kouto 1-1-1, Sayo...hutch 3 of SACLA with the approval of the Japan Synchrotron Radiation Research Institute (JASRI) (Proposal No...

2014-01-01T23:59:59.000Z

189

Opportunities and challenges for time-resolved studies of protein structural dynamics at X-ray free-electron lasers  

Science Journals Connector (OSTI)

...functional transitions in proteins. Proc. Natl Acad...Woodbury, NW. 2007 Protein dynamics control the...2011 New light on disordered ensembles: ab initio structure...vibrational dynamics of a protein in liquid water by terahertz...

2014-01-01T23:59:59.000Z

190

Using Lasers and X-rays to Reveal the Motion of Atoms and Electrons  

ScienceCinema (OSTI)

July 7, 2009 Berkeley Lab summer lecture: The ultrafast motion of atoms and electrons lies at the heart of chemical reactions, advanced materials with exotic properties, and biological processes such as the first event in vision. Bob Schoenlein, Deputy Director for Science at the Advanced Light Source, will discuss how such processes are revealed by using laser pulses spanning a millionth of a billionth of a second, and how a new generation of light sources will bring the penetrating power of x-rays to the world of ultrafast science

Bob Schoenlein

2010-01-08T23:59:59.000Z

191

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

E-Print Network [OSTI]

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

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

2014-01-01T23:59:59.000Z

192

A New Gated X-Ray Detector for the Orion Laser Facility  

SciTech Connect (OSTI)

Gated X-Ray Detectors (GXD) are considered the work-horse target diagnostic of the laser based inertial confinement fusion (ICF) program. Recently, Los Alamos National Laboratory (LANL) has constructed three new GXDs for the Orion laser facility at the Atomic Weapons Establishment (AWE) in the United Kingdom. What sets these three new instruments apart from the what has previously been constructed for the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) is: improvements in detector head microwave transmission lines, solid state embedded hard drive and updated control software, and lighter air box design and other incremental mechanical improvements. In this paper we will present the latest GXD design enhancements and sample calibration data taken on the Trident laser facility at Los Alamos National Laboratory using the newly constructed instruments.

Clark, David D. [Los Alamos National Laboratory; Aragonez, Robert J. [Los Alamos National Laboratory; Archuleta, Thomas N. [Los Alamos National Laboratory; Fatherley, Valerie E. [Los Alamos National Laboratory; Hsu, Albert H. [Los Alamos National Laboratory; Jorgenson, H. J. [Los Alamos National Laboratory; Mares, Danielle [Los Alamos National Laboratory; Oertel, John A. [Los Alamos National Laboratory; Oades, Kevin [Atomic Weapons Establishment; Kemshall, Paul [Atomic Weapons Establishment; Thomas, Philip [Atomic Weapons Establishment; Young, Trevor [Atomic Weapons Establishment; Pederson, Neal [VI Control Systems

2012-08-08T23:59:59.000Z

193

Initial optical-transition radiation measurements of the electron beam for the Boeing free-electron-laser experiment  

Science Journals Connector (OSTI)

The potential for characterization of electron beams at ? 100 MeV at the Boeing Free Electron Laser (FEL) facility by optical-transition radiation (OTR) techniques has been demonstrated as an important complement to other diagnostic means. Electron beam properties such as spatial profile and position, current intensity, emittance and energy were studied using OTR. Initial examples including transport through the 5 m wiggler and the resolution of Cherenkov radiation and spontaneous-emission radiation competitive sources are discussed.

A.H. Lumpkin; R.B. Fiorito; D.W. Rule; D.H. Dowell; W.C. Sellyey; A.R. Lowrey

1990-01-01T23:59:59.000Z

194

Study of 1–8 keV K-? x-ray emission from high intensity femtosecond laser produced plasma  

SciTech Connect (OSTI)

We report an experimental study on the optimization of a laser plasma based x-ray source of ultra-short duration K-? line radiation. The interaction of pulses from a CPA based Ti:sapphire laser (10 TW, 45 fs, 10 Hz) system with magnesium, titanium, iron and copper solid target generates bright 1-8 keV K-? x-ray radiation. The x-ray yield was optimized with the laser pulse duration (at fixed fluence) which is varied in the range of 45 fs to 1.4 ps. It showed a maximum at laser pulse duration of ?740 fs, 420 fs, 350 and 250 fs for Mg (1.3 keV), Ti (4.5 keV), Fe (6.4 keV) and Cu (8.05 keV) respectively. The x-ray yield is observed to be independent of the sign of the chirp. The scaling of the K-? yield (I{sub x} ? I{sub L}{sup ?}) for 45 fs and optimized pulse duration were measured for laser intensities in the region of 3 × 10{sup 14} – 8 × 10{sup 17}. The x-ray yield shows a much faster scaling exponent ? = 1.5, 2.1, 2.4 and 2.6 for Mg, Ti, Fe and Cu respectively at optimized pulse duration compared to scaling exponent of 0.65, 1.3, 1.5, and 1.7 obtained for 45 fs duration laser pulses. The laser to x-ray energy conversion efficiencies obtained for different target materials are ?{sub Mg} = 1.2 × 10{sup ?5}, ?{sub Ti} = 3.1 × 10{sup ?5}, ?{sub Fe} = 2.7 × 10{sup ?5}, ?{sub Cu} = 1.9 × 10{sup ?5}. The results have been explained from the efficient generation of optimal energy hot electrons at longer laser pulse duration. The faster scaling observed at optimal pulse duration indicates that the x-ray source is generated at the target surface and saturation of x-ray emission would appear at larger laser fluence. An example of utilization of the source for measurement of shock-wave profiles in a silicon crystal by time resolved x-ray diffraction is also presented.

Arora, V., E-mail: arora@rrcat.gov.in; Naik, P. A.; Chakera, J. A.; Bagchi, S.; Tayyab, M.; Gupta, P. D. [Laser Plasma Division, Raja Rammana Centre for Advanced Technology, Indore 452 013 (India)] [Laser Plasma Division, Raja Rammana Centre for Advanced Technology, Indore 452 013 (India)

2014-04-15T23:59:59.000Z

195

Spectral-phase interferometry for direct electric-field reconstruction applied to seeded extreme-ultraviolet free-electron lasers  

E-Print Network [OSTI]

We present a setup for complete characterization of femtosecond pulses generated by seeded free-electron lasers (FEL's) in the extreme-ultraviolet spectral region. Two delayed and spectrally shifted replicas are produced and used for spectral phase interferometry for direct electric field reconstruction (SPIDER). We show that it can be achieved by a simple arrangement of the seed laser. Temporal shape and phase obtained in FEL simulations are well retrieved by the SPIDER reconstruction, allowing to foresee the implementation of this diagnostic on existing and future sources. This will be a significant step towards an experimental investigation and control of FEL spectral phase.

Mahieu, Benoît; De Ninno, Giovanni; Dacasa, Hugo; Lozano, Magali; Rousseau, Jean-Philippe; Zeitoun, Philippe; Garzella, David; Merdji, Hamed

2015-01-01T23:59:59.000Z

196

Bright x-ray sources from laser irradiation of foams with high concentration of Ti  

SciTech Connect (OSTI)

Low-density foams irradiated by a 20 kJ laser at the Omega laser facility (Laboratory for Laser Energetics, Rochester, NY, USA) are shown to convert more than 5% of the laser energy into 4.6 to 6.0?keV x rays. This record efficiency with foam targets is due to novel fabrication techniques based on atomic-layer-deposition of Ti atoms on an aerogel scaffold. A Ti concentration of 33 at.?% was obtained in a foam with a total density of 5?mg/cm{sup 3}. The dynamics of the ionization front through these foams were investigated at the 1 kJ laser of the Gekko XII facility (Institute for Laser Engineering, Osaka, Japan). Hydrodynamic simulations can reproduce the average electron temperature but fail to predict accurately the heat front velocity in the foam. This discrepancy is shown to be unrelated to the possible water adsorbed in the foam but could be attributed to effects of the foam micro-structure.

Pérez, F., E-mail: perez75@llnl.gov; Patterson, J. R.; May, M.; Colvin, J. D.; Biener, M. M.; Wittstock, A.; Kucheyev, S. O.; Charnvanichborikarn, S.; Satcher, J. H.; Gammon, S. A.; Poco, J. F.; Fournier, K. B. [Lawrence Livermore National Laboratory, 7000 East Ave., Livermore, California 94550 (United States)] [Lawrence Livermore National Laboratory, 7000 East Ave., Livermore, California 94550 (United States); Fujioka, S.; Zhang, Z.; Ishihara, K.; Tanaka, N.; Ikenouchi, T.; Nishimura, H. [Institute of Laser Engineering, Osaka University, 2-6 Yamada-Oka, Suita, Osaka 565-0871 (Japan)] [Institute of Laser Engineering, Osaka University, 2-6 Yamada-Oka, Suita, Osaka 565-0871 (Japan)

2014-02-15T23:59:59.000Z

197

Cluster beam targets for laser plasma extreme ultraviolet and soft x-ray sources  

DOE Patents [OSTI]

Method and apparatus for producing extreme ultraviolet (EUV) and soft x-ray radiation from an ultra-low debris plasma source are disclosed. Targets are produced by the free jet expansion of various gases through a temperature controlled nozzle to form molecular clusters. These target clusters are subsequently irradiated with commercially available lasers of moderate intensity (10{sup 11}--10{sup 12} watts/cm{sup 2}) to produce a plasma radiating in the region of 0.5 to 100 nanometers. By appropriate adjustment of the experimental conditions the laser focus can be moved 10--30 mm from the nozzle thereby eliminating debris produced by plasma erosion of the nozzle. 5 figs.

Kublak, G.D.; Richardson, M.C.

1996-11-19T23:59:59.000Z

198

Cluster beam targets for laser plasma extreme ultraviolet and soft x-ray sources  

DOE Patents [OSTI]

Method and apparatus for producing extreme ultra violet (EUV) and soft x-ray radiation from an ultra-low debris plasma source are disclosed. Targets are produced by the free jet expansion of various gases through a temperature controlled nozzle to form molecular clusters. These target clusters are subsequently irradiated with commercially available lasers of moderate intensity (10.sup.11 -10.sup.12 watts/cm.sup.2) to produce a plasma radiating in the region of 0.5 to 100 nanometers. By appropriate adjustment of the experimental conditions the laser focus can be moved 10-30 mm from the nozzle thereby eliminating debris produced by plasma erosion of the nozzle.

Kublak, Glenn D. (124 Turquoise Way, Livermore, Alameda County, CA 94550); Richardson, Martin C. (CREOL

1996-01-01T23:59:59.000Z

199

High-resolution multi-MeV x-ray radiography using relativistic laser-solid interaction  

SciTech Connect (OSTI)

When high intensity ({>=}10{sup 19} W cm{sup -2}) laser light interacts with matter, multi-MeV electrons are produced. These electrons can be utilized to generate a MeV bremsstrahlung x-ray emission spectrum as they propagate into a high-Z solid target positioned behind the interaction area. The short duration (<10 ps) and the small diameter (<500 {mu}m) of the x-ray pulse combined with the MeV x-ray spectrum offers an interesting alternative to conventional bremsstrahlung x-ray sources based on an electron accelerator used to radiograph dense, rapidly moving objects. In experiments at the Omega EP laser, a multi-MeV x-ray source is characterized consistently with number of independent diagnostics. An unfiltered x-ray dose of approximately 2 rad in air at 1 m and a source diameter of less than 350 {mu}m are inferred. Radiography of a complex and high area density (up to 61 g/cm{sup 2}) object is then performed with few hundred microns spatial resolution.

Courtois, C.; Compant La Fontaine, A.; Barbotin, M.; Bazzoli, S.; Brebion, D.; Bourgade, J. L.; Gazave, J.; Lagrange, J. M.; Landoas, O.; Le Dain, L.; Lefebvre, E.; Pichoff, N. [CEA, DAM, DIF, F-91297 Arpajon (France); Edwards, R.; Aedy, C.; Biddle, L.; Drew, D.; Gardner, M.; Ramsay, M.; Simons, A.; Sircombe, N. [AWE Plc., Aldermaston, Reading RG7 4PR (United Kingdom)

2011-02-15T23:59:59.000Z

200

CW 100 kW radio frequency-free-electron laser design at 10. mu. m  

SciTech Connect (OSTI)

This paper describes the 100 kW CW radio frequency-free-electron last at 10{mu}m to be built at Boeing Defense and Space Group in collaboration with Los Alamos National Laboratory. The authors discuss the criteria which led to the selection of the operating point, the single-accelerator master-oscillator and power-amplifier configuration, the goals of this experiment, and the expected performance.

Parazzoli, C.G.; Rodenburg, R.E.; Romero, J.B.; Adamski, J.L.; Pistoresi, D.J.; Shoffstall, D.R. (Boeing Defense and Space Group, Seattle, WA (US)); Quimby, D.C. (STI Optronics, Inc., Bellevue, WA (US))

1991-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "x-ray free-electron laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Towards hard x-ray imaging at GHz frame rate  

SciTech Connect (OSTI)

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

Wang Zhehui; Morris, C. L.; Kapustinsky, J. S.; Kwiatkowski, K.; Luo, S.-N. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

2012-10-15T23:59:59.000Z

202

Towards hard X-ray imaging at GHz frame rate  

SciTech Connect (OSTI)

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

Wang, Zhehui [Los Alamos National Laboratory; Morris, Christopher [Los Alamos National Laboratory; Luo, Shengnian [Los Alamos National Laboratory; Kwiatkowski, Kris K. [Los Alamos National Laboratory; Kapustinsky, Jon S. [Los Alamos National Laboratory

2012-05-02T23:59:59.000Z

203

Nonlinear X-ray Compton Scattering  

E-Print Network [OSTI]

X-ray scattering is a weak linear probe of matter. It is primarily sensitive to the position of electrons and their momentum distribution. Elastic X-ray scattering forms the basis of atomic structural determination while inelastic Compton scattering is often used as a spectroscopic probe of both single-particle excitations and collective modes. X-ray free-electron lasers (XFELs) are unique tools for studying matter on its natural time and length scales due to their bright and coherent ultrashort pulses. However, in the focus of an XFEL the assumption of a weak linear probe breaks down, and nonlinear light-matter interactions can become ubiquitous. The field can be sufficiently high that even non-resonant multiphoton interactions at hard X-rays wavelengths become relevant. Here we report the observation of one of the most fundamental nonlinear X-ray-matter interactions, the simultaneous Compton scattering of two identical photons producing a single photon at nearly twice the photon energy. We measure scattered...

Fuchs, Matthias; Chen, Jian; Ghimire, Shambhu; Shwartz, Sharon; Kozina, Michael; Jiang, Mason; Henighan, Thomas; Bray, Crystal; Ndabashimiye, Georges; Bucksbaum, P H; Feng, Yiping; Herrmann, Sven; Carini, Gabriella; Pines, Jack; Hart, Philip; Kenney, Christopher; Guillet, Serge; Boutet, Sebastien; Williams, Garth; Messerschmidt, Marc; Seibert, Marvin; Moeller, Stefan; Hastings, Jerome B; Reis, David A

2015-01-01T23:59:59.000Z

204

High-average-power, 100-Hz-repetition-rate, tabletop soft-x-ray lasers at sub-15-nm wavelengths  

SciTech Connect (OSTI)

Efficient excitation of dense plasma columns at 100-Hz repetition rate using a tailored pump pulse profile produced a tabletop soft-x-ray laser average power of 0.1 mW at = 13.9 nm and 20 W at = 11.9 nm from transitions of Ni-like Ag and Ni-like Sn, respectively. Lasing on several other transitions with wavelengths between 10.9 and 14.7 nm was also obtained using 0.9-J pump pulses of 5-ps duration from a compact diode-pumped chirped pulse amplification Yb:YAG laser. Hydrodynamic and atomic plasma simulations show that the pump pulse profile, consisting of a nanosecond ramp followed by two peaks of picosecond duration, creates a plasma with an increased density of Ni-like ions at the time of peak temperature that results in a larger gain coefficient over a temporally and spatially enlarged space leading to a threefold increase in the soft-x-ray laser output pulse energy. The high average power of these compact soft-x-ray lasers will enable applications requiring high photon flux. These results open the path to milliwatt-average-power tabletop soft-x-ray lasers.

Reagan, Brendon [Colorado State University, Fort Collins] [Colorado State University, Fort Collins; Berrill, Mark A [ORNL] [ORNL; Wernsing, Keith [Colorado State University, Fort Collins] [Colorado State University, Fort Collins; Baumgarten, Cory [Colorado State University, Fort Collins] [Colorado State University, Fort Collins; Woolston, Mark [Colorado State University, Fort Collins] [Colorado State University, Fort Collins; Rocca, Jorge [Colorado State University, Fort Collins] [Colorado State University, Fort Collins

2014-01-01T23:59:59.000Z

205

Traces on ion yields and electron spectra of Ar inner-shell hollow states with Free-Electron Lasers  

E-Print Network [OSTI]

We explore the formation by Free-Electron-Laser radiation of Ar hollow states with two or three inner-shell holes. We find that even charged Ar ion states can be more populated than odd charged Ar ion states. This depends on the pulse intensity and the number of energetically accessible inner- shell holes. Fully accounting for fine structure, we demonstrate that one electron spectra bare the imprints of Ar hollow states with two inner-shell holes. Moreover, we show how the Auger spectra of these hollow states can be extracted from two-electron coincidence spectra.

Wallis, A O G; Emmanouilidou, A

2015-01-01T23:59:59.000Z

206

Time-Resolved Synchrotron X-ray Diffraction on Pulse Laser Heated Iron in Diamond Anvil Cell  

SciTech Connect (OSTI)

The authors present time-resolved synchrotron x-ray diffraction to probe the {var_epsilon}-{delta} phase transition of iron during pulse-laser heating in a diamond anvil cell. The system utilizes a monochromatic synchrotron x-ray beam, a two-dimensional pixel array x-ray detector and a dual beam, double side laser-heating system. Multiple frames of the diffraction images are obtained in real-time every 22 ms over 500 ms of the entire pulse heating period. The results show the structural evolution of iron phases at 17 GPa, resulting in thermal expansion coefficient 1/V({Delta}V/{Delta}T){sub p} = 7.1 * 10{sup -6}/K for {var_epsilon}-Fe and 2.4 * 10{sup -5}/K for {gamma}-Fe, as well as the evidence for metastability of {gamma}-Fe at low temperatures below the {var_epsilon}-{gamma} phase boundary.

Yoo, C S; Wei, H; Dias, R; Shen, G; Smith, J; Chen, J Y; Evans, W

2011-09-21T23:59:59.000Z

207

X-ray backlight measurement of preformed plasma by kJ-class petawatt LFEX laser  

SciTech Connect (OSTI)

Foot and pedestal pulses that precede the main pulse from a high-intensity laser greatly affect laser-plasma interactions. Especially in fast ignition schemes, preceding pulses generate a plasma prior to irradiation by the main pulse. This results in a too energetic and divergent electron beam being generated in the preformed plasma, which reduces the energy coupling efficiency from the heating laser to the dense fuel core. A preformed plasma with a density scale length of 40-60 {mu}m was observed by a time- and space-resolved x-ray backlight technique using the LFEX laser system at the Institute of Laser Engineering, Osaka University. Preceding pulses (i.e., the foot and pedestal) of the LFEX were characterized by comparing observations with calculations results obtained using a two-dimension (2D) radiation-hydrodynamic simulation code. In a separate experiment, the 2D code was benchmarked with the experimentally observed hydrodynamic behavior of a gold plasma produced by a nanosecond laser pulse that mimicked foot and pedestal pulses (intensity: 1 Multiplication-Sign 10{sup 11}-1 Multiplication-Sign 10{sup 12}W/cm{sup 2}). The preceding pulses were estimated to have an intensity of 1 Multiplication-Sign 10{sup 12}-10{sup 13}W/cm{sup 2}, a duration of 2.0 ns, and a spot diameter at the target of 200-600 {mu}m by comparing the measured hydrodynamics of the preformed plasma with that calculated by the 2D hydrodynamic simulation code.

Ohira, Shinji; Fujioka, Shinsuke; Nagatomo, Hideo; Matsuo, Satoshi; Morio, Noboru; Kawanaka, Jyunji; Nakata, Yoshiki; Miyanaga, Noriaki; Shiraga, Hiroyuki; Nishimura, Hiroaki; Azechi, Hiroshi [Institute of Laser Engineering, Osaka University, 2-6 Yamada-oka, Suita Osaka 565-0871 (Japan); Sunahara, Atsushi [Institute for Laser Technology, 2-6 Yamada-oka, Suita Osaka 565-0871 (Japan); Johzaki, Tomoyuki [Graduate School of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi Hiroshima 739-8527 (Japan)

2012-09-15T23:59:59.000Z

208

Femtosecond Time-Delay X-ray Holography  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Time-Delay X-ray Holography Time-Delay X-ray Holography X-ray free-electron lasers (XFELs) will produce photon pulses with a unique and desirable combination of properties. Their short X-ray wavelengths allow penetration into materials and the ability to probe structure at and below the nanometer scale. Their ultra-short duration gives information about this structure at the fundamental time-scales of atoms and molecules. The extreme intensity of the pulses will allow this information to be acquired in a single shot, so that these studies can be carried out on non-repeatable processes or on weakly-scattering objects that will be modified by the pulse. A fourth property of XFEL pulses is their high transverse coherence, which brings the promise of decades of innovation in visible optics to the X-ray regime, such as holography, interferometry, and laser-based imaging. Making an effective use of XFEL pulses, however, will benefit from innovations that are new to both X-ray science and coherent optics. One such innovation is the new method of time-delay X-ray holography [i], recently demonstrated at the FLASH FEL at DESY in Hamburg, to measure the evolution of objects irradiated by intense pulses.

209

X-ray lasers and methods utilizing two component driving illumination provided by optical laser means of relatively low energy and small physical size  

DOE Patents [OSTI]

An X-ray laser (10), and related methodology, are disclosed wherein an X-ray laser target (12) is illuminated with a first pulse of optical laser radiation (14) of relatively long duration having scarcely enough energy to produce a narrow and linear cool plasma of uniform composition (38). A second, relatively short pulse of optical laser radiation (18) is uniformly swept across the length, from end to end, of the plasma (38), at about the speed of light, to consecutively illuminate continuously succeeding portions of the plasma (38) with optical laser radiation having scarcely enough energy to heat, ionize, and invert them into the continuously succeeding portions of an X-ray gain medium. This inventive double pulse technique results in a saving of more than two orders of magnitude in driving optical laser energy, when compared to the conventional single pulse approach.

Rosen, Mordecai D. (Berkeley, CA); Matthews, Dennis L. (El Granada, CA)

1991-01-01T23:59:59.000Z

210

Damage of supercoiled DNA by an ultrafast laser-driven electron x-ray source  

Science Journals Connector (OSTI)

Using magnetic fields to differentiate the effects of electrons and x-rays, it was discovered that single strand breaks in supercoiled DNA were

Shan, Fang; Carter, Joshua D; Guo, Ting

2007-01-01T23:59:59.000Z

211

Search for Photon-Photon Elastic Scattering in the X-ray Region  

E-Print Network [OSTI]

We report the first results of a search for real photon-photon scattering using X rays. A novel system is developed to split and collide X-ray pulses by applying interferometric techniques. A total of $6.5\\times10^{5}$ pulses (each containing about $10^{11}$ photons) from an X-ray Free-Electron Laser are injected into the system. No scattered events are observed, and an upper limit of $1.7\\times 10^{-24}$ ${\\rm m^{2}}$ (95% C.L.) is obtained on the photon-photon elastic scattering cross section at 6.5 keV.

T. Inada; T. Yamaji; S. Adachi; T. Namba; S. Asai; T. Kobayashi; K. Tamasaku; Y. Tanaka; Y. Inubushi; K. Sawada; M. Yabashi; T. Ishikawa

2014-04-18T23:59:59.000Z

212

Quantum coherence in the dynamical excitation, ionization, and decaying of neon gas induced by X-ray laser  

E-Print Network [OSTI]

We develop a large scale quantum master equation approach to describe dynamical processes of practical open quantum systems driven by both coherent and stochastic interactions by including more than one thousand true states of the systems, motivated by the development of highly bright and fully coherent lasers in the X-ray wavelength regime. The method combines the processes of coherent dynamics induced by the X-ray laser and incoherent relaxations due to spontaneous emissions, Auger decays, and electronic collisions. As examples, theoretical investigation of {\\it real} coherent dynamics of inner-shell electrons of a neon gas, irradiated by a high-intensity X-ray laser with a full temporal coherence, is carried out with the approach. In contrast to the rate equation treatment, we find that coherence can suppress the multiphoton absorptions of a neon gas in the ultra-intense X-ray pulse, due to coherence-induced Rabi oscillations and power broadening effects. We study the influence of coherence on ionization p...

Li, Yongqiang; Dong, Wenpu; Zeng, Jiaolong; Yuan, Jianmin

2015-01-01T23:59:59.000Z

213

Spatial Gradients in Particle Reinforced Polymers Characterized by X-Ray Attenuation and Laser Confocal Microscopy  

SciTech Connect (OSTI)

The goal of this work is to develop techniques for measuring gradients in particle concentration within filled polymers, such as encapsulant. A high concentration of filler particles is added to such materials to tailor physical properties such as thermal expansion coefficient. Sedimentation and flow-induced migration of particles can produce concentration gradients that are most severe near material boundaries. Therefore, techniques for measuring local particle concentration should be accurate near boundaries. Particle gradients in an alumina-filled epoxy resin are measured with a spatial resolution of 0.2 mm using an x-ray beam attenuation technique, but an artifact related to the finite diameter of the beam reduces accuracy near the specimen's edge. Local particle concentration near an edge can be measured more reliably using microscopy coupled with image analysis. This is illustrated by measuring concentration profiles of glass particles having 40 {micro}m median diameter using images acquired by a confocal laser fluorescence microscope. The mean of the measured profiles of volume fraction agrees to better than 3% with the expected value, and the shape of the profiles agrees qualitatively with simple theory for sedimentation of monodisperse particles. Extending this microscopy technique to smaller, micron-scale filler particles used in encapsulant for microelectronic devices is illustrated by measuring the local concentration of an epoxy resin containing 0.41 volume fraction of silica.

LAGASSE,ROBERT R.; THOMPSON,KYLE R.

2000-06-12T23:59:59.000Z

214

Simulation of a high-gain tapered-wiggler free-electron laser  

SciTech Connect (OSTI)

We present results from a numerical model of a high-gain (electron-beam power > input laser beam power) FEL amplifier.

Fawley, W.M.; Scharlemann, E.T.; Prosnitz, D.

1983-09-27T23:59:59.000Z

215

Searching for plasmas with anomalous dispersion in the soft X-ray regime  

SciTech Connect (OSTI)

Over the last decade the electron density of plasmas has been measured using X-ray laser interferometers in the 14 to 47 nm wavelength regime. With the same formula used in decades of experiments with optical interferometers, the data analysis assumes the index of refraction is due only to the free electrons, which makes the index less than one. Over the last several years, interferometer experiments in C, Al, Ag, and Sn plasmas have observed plasmas with index of refraction greater than one at 14 or 47 nm and demonstrated unequivocally that the usual formula for calculating the index of refraction is not always valid as the contribution from bound electrons can dominate the free electrons in certain cases. In this paper we search for other materials with strong anomalous dispersion that could be used in X-ray laser interferometer experiments to help understand this phenomena. An average atom code is used to calculate the plasma properties. This paper discusses the calculations of anomalous dispersion in Ne and Na plasmas near 47 nm and Xe plasmas near 14 nm. With the advent of the FLASH X-ray free electron laser in Germany and the LCLS X-FEL coming online at Stanford in 2 years the average atom code will be an invaluable tool to explore plasmas at higher X-ray energy to identify potential experiments for the future. During the next decade X-ray free electron lasers and other X-ray sources will be used to probe a wider variety of plasmas at higher densities and shorter wavelengths so understanding the index of refraction in plasmas will be even more essential.

Nilsen, J; Johnson, W R; Cheng, K T

2007-08-24T23:59:59.000Z

216

High-current-density, high brightness cathodes for free electron laser applications  

SciTech Connect (OSTI)

This report discusses the following topics: brightness and emittance of electron beams and cathodes; general requirements for cathodes in high brightness electron guns; candidate cathode types; plasma and field emission cathodes; true field emission cathodes; oxide cathodes; lanthanum hexaborides cathodes; laser driven thermionic cathodes; laser driven photocathodes; impregnated porous tungsten dispenser cathodes; and choice of best performing cathode types.

Green, M.C. (Varian Associates, Palo Alto, CA (USA). Palo Alto Microwave Tube Div.)

1987-06-01T23:59:59.000Z

217

The analysis of single-electron orbits in a free electron laser based upon a rectangular hybrid wiggler  

SciTech Connect (OSTI)

A three-dimensional analysis of a novel free-electron laser (FEL) based upon a rectangular hybrid wiggler (RHW) is presented. This RHW is designed in a configuration composed of rectangular rings with alternating ferrite and dielectric spacers immersed in a solenoidal magnetic field. An analytic model of RHW is introduced by solution of Laplace's equation for the magnetostatic fields under the appropriate boundary conditions. The single-electron orbits in combined RHW and axial guide magnetic fields are studied when only the first and the third spatial harmonic components of the RHW field are taken into account and the higher order terms are ignored. The results indicate that the third spatial harmonic leads to group III orbits with a strong negative mass regime particularly in large solenoidal magnetic fields. RHW is found to be a promising candidate with favorable characteristics to be used in microwave FEL.

Kordbacheh, A.; Ghahremaninezhad, Roghayeh [Department of Physics, Iran University of Science and Technology, 1684613114 Tehran (Iran, Islamic Republic of); Maraghechi, B. [Department of Physics, Amirkabir University of Technology, 159163411 Tehran (Iran, Islamic Republic of)

2012-09-15T23:59:59.000Z

218

Mapping the Ionization State of Laser-Irradiated Ar Gas Jets With Multi-Wavelength Monochromatic X-Ray Imaging  

SciTech Connect (OSTI)

Two-dimensional monochromatic images of fast-electron stimulated Ar K{alpha} and He-{alpha} x-ray self-emission have recorded a time-integrated map of the extent of Ar{sup {approx}6+} and Ar{sup 16+} ions, respectively, within a high density (10{sup 20} cm{sup -3} atomic density) Ar plasma. This plasma was produced by irradiating a 2 mm wide clustering Ar gas jet with an ultra-high intensity (10{sup 19} W/cm{sup 2}, 200 fs) Ti:Sapphire laser operating at 800 nm. Spherically bent quartz crystals in the 200 (for K{alpha}) and 201 (for He-{alpha}) planes were used as near-normal incidence reflective x-ray optics. We see that a large (830 {micro}m long) region of plasma emits K{alpha} primarily along the laser axis, while the He-{alpha} emission is confined to smaller hot spot (230 {micro}m long) region that likely corresponds to the focal volume of the f/8 laser beam. X-ray spectra from a Bragg spectrometer operating in the von Hamos geometry, which images in one dimension, indicate that the centroids of the K{alpha} and He-{alpha} emission regions are separated by approximately 330 {micro}m along the laser axis.

Kugland, N L; Doppner, T; Kemp, A; Schaeffer, D; Glenzer, S H; Niemann, C

2010-04-08T23:59:59.000Z

219

High-resolution X-ray spectroscopy of hollow atoms created in plasma heated by subpicosecond laser radiation  

SciTech Connect (OSTI)

The investigations of ultrashort (0.4-0.6 ps) laser pulse radiation interaction with solid targets have been carried out. The Trident subpicosecond laser system was used for plasma creation. The X-ray plasma emission was investigated with the help of high-resolution spectrographs with spherically bent mica crystals. It is shown that when high contrast ultrashort laser pulses were used for plasma heating its emission spectra could not be explained in terms of commonly used theoretical models, and transitions in so called {open_quotes}hollow atoms{close_quotes} must be taken into account for adequate description of plasma radiation.

Faenov, A.Ya.; Magunov, A.I.; Pikuz, T.A. [Multicharged Ions Spectra Data Center of VNIIFTRI, Moscow (Russian Federation)] [and others

1997-10-01T23:59:59.000Z

220

All-laser-driven, MeV-energy X-ray source for detection of SNM Sudeep Banerjee, Nathan Powers, Vidya Ramanathan, Nathaniel Cunningham, Nate Chandler-Smith, Shouyuan  

E-Print Network [OSTI]

All-laser-driven, MeV-energy X-ray source for detection of SNM Sudeep Banerjee, Nathan Powers, MI 48109. A quasi-monoenergetic MeV x-ray source based on laser-driven electron acceleration per laser shot. Characterization of such a high-flux high energy x-ray beam is in progress. Quasi

Umstadter, Donald

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221

Interaction of soft x-ray laser pulse radiation with aluminum surface: Nano-meter size surface modification  

SciTech Connect (OSTI)

Interaction of soft x-ray laser radiation with material and caused modification of the exposed surface has both physical and practical interests. We irradiated the focusing soft x-ray laser (SXRL) pulses having a wavelength of 13.9 nm and the duration of 7 ps to aluminum (Al) surface. After the SXRL irradiation process, the irradiated Al surface was observed with a scanning electron microscope. The surface modifications caused by SXRL single pulse exposure were clearly seen. In addition, it was found that the conical structures having around 100 nm in diameters were formed in the shallow features. The nano-meter size modified structures at Al surface induced by SXRL pulse is interesting as the newly surface structure. Hence, the SXRL beam would be a candidate for a tool of micromachining. We also provide a thermomechanical modeling of SXRL interaction with Al briefly to explain the surface modification.

Ishino, Masahiko; Faenov, Anatoly; Tanaka, Momoko; Hasegawa, Noboru; Nishikino, Masaharu; Tamotsu, Satoshi; Pikuz, Tatiana; Inogamov, Nail; Zhakhovsky, Vasily; Skobelev, Igor; Fortov, Vladimir; Khohlov, Viktor; Shepelev, Vadim; Ohba, Toshiyuki; Kaihori, Takeshi; Ochi, Yoshihiro; Imazono, Takashi; Kawachi, Tetsuya [Quantum Beam Science Directorate, Japan Atomic Energy Agency, Kyoto 619-0215 (Japan); Joint Institute for High Temperatures, Russian Academy of Science, Moscow 125412 (Russian Federation); Graduate School of Humanities and Science, Nara Women's University, Nara 630-8506 (Japan); Landau Institute for Theoretical Physics, Russian Academy of Science, Chernogolovka 142432 (Russian Federation); Institute for Computer Aided Design, Russian Academy of Science, Moscow 123056 (Russian Federation)

2012-07-11T23:59:59.000Z

222

X-ray beamsplitter  

DOE Patents [OSTI]

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.

Ceglio, N.M.; Stearns, D.G.; Hawryluk, A.M.; Barbee, T.W. Jr.

1987-08-07T23:59:59.000Z

223

X-ray beamsplitter  

DOE Patents [OSTI]

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.

Ceglio, Natale M. (Livermore, CA); Stearns, Daniel S. (Mountain View, CA); Hawryluk, Andrew M. (Modesto, CA); Barbee, Jr., Troy W. (Palo Alto, CA)

1989-01-01T23:59:59.000Z

224

High-Gain Harmonic Generation Free-Electron Laser at Saturation  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

shown in Fig. 1. Fig.1. HGHG ATF layout The frequency-quadrupled Nd:YAG photocathode-rf gun drive-laser has a pulse length of 8 ps and an energy of 8 J resulting in a 6-ps FWHM...

225

Simulations of the Rocketdyne free-electron laser with a 4 m wiggler  

Science Journals Connector (OSTI)

Rocketdyne is assembling a high-brightness 78 MeV FEL. After full development the laser will be capable of an average output of greater than 1 kW. Performance calculations using the Rocketdyne FELOPT code are presented for a 1.06 ?m system.

R.A. Cover; G.T. Bennett; R.J. Burke; M.S. Curtin; M.C. Lampel; G. Rakowsky

1992-01-01T23:59:59.000Z

226

Spectrum bandwidth narrowing of Thomson scattering X-rays with energy chirped electron beams from laser wakefield acceleration  

SciTech Connect (OSTI)

We study incoherent Thomson scattering between an ultrashort laser pulse and an electron beam accelerated from a laser wakefield. The energy chirp effects of the accelerated electron beam on the final radiation spectrum bandwidth are investigated. It is found that the scattered X-ray radiation has the minimum spectrum width and highest intensity as electrons are accelerated up to around the dephasing point. Furthermore, it is proposed that the electron acceleration process inside the wakefield can be studied by use of 90° Thomson scattering. The dephasing position and beam energy chirp can be deduced from the intensity and bandwidth of the scattered radiation.

Xu, Tong; Chen, Min, E-mail: minchen@sjtu.edu.cn; Li, Fei-Yu; Yu, Lu-Le [Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China)] [Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Sheng, Zheng-Ming, E-mail: zmsheng@sjtu.edu.cn [Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China) [Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); SUPA, Department of Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Zhang, Jie [Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China) [Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Beijing National Laboratory of Condensed Matter Physics, Institute of Physics, CAS, Beijing 100190 (China)

2014-01-06T23:59:59.000Z

227

Spatial coherence measurements of a 13.2 nm transient nickel-like cadmium soft x-ray laser pumped at grazing incidence  

E-Print Network [OSTI]

K. Nishihara, “Spatial Coherence Measurement of 13.9 nm Ni-Transverse spatial coherence of a transient nickellikeanalysis of x-ray laser coherence”, Phys. Rev. Lett. 65, 16.

Lui, Y.; Wang, Y.; Larotonda, M.A.; Luther, B.M.; Rocca, J.J.; Attwood, D.T.

2006-01-01T23:59:59.000Z

228

Status of UCLA Helical Permanent-Magnet Inverse Free Electron Laser  

SciTech Connect (OSTI)

A helical undulator, utilizing permanent-magnet of cylindrically symmetric (Halbach) geometry is being developed at UCLA's Neptune Facility. The initial prototype is a short 10 cm, 7 periods long helical undulator, designed to test the electron-photon coupling by observing the micro-bunching is currently being constructed. The Neptune IFEL facility utilizes a 15 MeV Photoinjector-generated electron beam of 0.5 nC interacting with CO{sub 2} of peak energy up to 100 J, estimated to have acceleration of 100 MeV/m. An Open Iris-Loaded Waveguide Structure (OILS) scheme which conserves laser mode size and wave fronts throughout the undulator, is utilized to avoid Gouy phase shift caused by focusing of the drive laser. Undulator design was tested by computer simulations Radia and Genesis 1.3. Coherent Transition Radiation and Coherent Cherenkov Radiation will be used for micro-bunching diagnostic. Currently permanent dipoles and their aluminum holders have been built, and the project is in its final state of assembly and undulator testing.

Knyazik, A.; Tikhoplav, R.; Frederico, J. T.; Affolter, M.; Rosenzweig, J. B. [Department of Physics and Astronomy, UCLA, Los Angeles, California 90095 (United States)

2009-01-22T23:59:59.000Z

229

Demonstration of Successful X-ray Thomson Scattering Using Picosecond K-(alpha) X-ray Sources for the Characterization of Dense Heated Matter  

SciTech Connect (OSTI)

We discuss the first successful K-{alpha} x-ray Thomson scattering experiment from solid density plasmas for use as a diagnostic in determining the temperature, density, and ionization state of warm dense matter with picosecond resolution. The development of this source as a diagnostic and stringent requirements for successful K-{alpha} x-ray Thomson scattering are addressed. Data for the experimental techniques described in this paper [1] suggest the capability of single shot characterization of warm dense matter and the ability to use this scattering source at future Free Electron Lasers (FEL) where comparable scattering signal levels are predicted.

Kritcher, A; Neumayer, P; Lee, H J; Doeppner, T; Falcone, R; Glenzer, S; Morse, E C

2008-05-05T23:59:59.000Z

230

Development of Advanced Beam Halo Diagnostics at the Jefferson Lab Free-Electron-Laser Facility  

SciTech Connect (OSTI)

High average current and high brightness electron beams are needed for many applications. At the Jefferson Lab FEL facility, the search for dark matter with the FEL laser beam has produced some interesting results, and a second very promising experiment called ?DarkLight?, using the JLab Energy-recovery-linac (ERL) machine has been put forward. Although the required beam current has been achieved on this machine, one key challenge is the management of beam halo. At the University of Md. (UMD) we have demonstrated a high dynamic range halo measurement method using a digital micro-mirror array device (DMD). A similar system has been established at the JLab FEL facility as a joint effort by UMD and JLab to measure the beam halo on the high current ERL machine. Preliminary experiments to characterize the halo were performed on the new UV FEL. In this paper, the limitations of the present system will be analyzed and a discussion of other approaches (such as an optimized coronagraph) for further extending the dynamic range will be presented. We will also discuss the possibility of performing both longitudinal and transverse (3D) halo measurements together on a single system.

Shukui Zhang, Stephen Benson, Dave Douglas, Frederick Wilson, Hao Zhang, Anatoly Shkvarunets, Ralph Fiorito

2011-03-01T23:59:59.000Z

231

Study of electron acceleration and x-ray radiation as a function of plasma density in capillary-guided laser wakefield accelerators  

SciTech Connect (OSTI)

Laser wakefield electron acceleration in the blow-out regime and the associated betatron X-ray radiation were investigated experimentally as a function of the plasma density in a configuration where the laser is guided. Dielectric capillary tubes were employed to assist the laser keeping self-focused over a long distance by collecting the laser energy around its central focal spot. With a 40 fs, 16 TW pulsed laser, electron bunches with tens of pC charge were measured to be accelerated to an energy up to 300 MeV, accompanied by X-ray emission with a peak brightness of the order of 10{sup 21} ph/s/mm{sup 2}/mrad{sup 2}/0.1%BW. Electron trapping and acceleration were studied using the emitted X-ray beam distribution to map the acceleration process; the number of betatron oscillations performed by the electrons was inferred from the correlation between measured X-ray fluence and beam charge. A study of the stability of electron and X-ray generation suggests that the fluctuation of X-ray emission can be reduced by stabilizing the beam charge. The experimental results are in good agreement with 3D particle-in-cell (PIC) simulation.

Ju, J.; Döpp, A.; Cros, B. [Laboratoire de Physique des Gaz et des Plasmas, CNRS-Université Paris-Sud, 91405 Orsay (France)] [Laboratoire de Physique des Gaz et des Plasmas, CNRS-Université Paris-Sud, 91405 Orsay (France); Svensson, K.; Genoud, G.; Wojda, F.; Burza, M.; Persson, A.; Lundh, O.; Wahlström, C.-G. [Department of Physics, Lund University, P.O. Box 118, S-22100 Lund (Sweden)] [Department of Physics, Lund University, P.O. Box 118, S-22100 Lund (Sweden); Ferrari, H. [Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) and CNEA-CAB (Argentina)] [Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) and CNEA-CAB (Argentina)

2013-08-15T23:59:59.000Z

232

Study of beam transverse properties of a thermionic electron gun for application to a compact THz free electron laser  

SciTech Connect (OSTI)

A novel thermionic electron gun adopted for use in a high power THz free electron laser (FEL) is proposed in this paper. By optimization of the structural and radiofrequency (RF) parameters, the physical design of the gun is performed using dynamic calculations. Velocity bunching is used to minimize the bunch's energy spread, and the dynamic calculation results indicate that high quality beams can be provided. The transverse properties of the beams generated by the gun are also analyzed. The novel RF focusing effects of the resonance cavity are investigated precisely and are used to establish emittance compensation, which enables the injector length to be reduced. In addition, the causes of the extrema of the beam radius and the normalized transverse emittance are analyzed and interpreted, respectively, and slice simulations are performed to illustrate how the RF focusing varies along the bunch length and to determine the effects of that variation on the emittance compensation. Finally, by observation of the variations of the beam properties in the drift tube behind the electron gun, prospective assembly scenarios for the complete THz-FEL injector are discussed, and a joint-debugging process for the injector is implemented.

Hu, Tongning, E-mail: TongningHu@hust.edu.cn, E-mail: yjpei@ustc.edu.cn; Qin, Bin; Tan, Ping; Chen, Qushan; Yang, Lei [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan 430074 (China); Pei, Yuanji, E-mail: TongningHu@hust.edu.cn, E-mail: yjpei@ustc.edu.cn; Li, Ji [National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (China)

2014-10-15T23:59:59.000Z

233

Calculations for Ni-like soft x-ray lasers: Optimization for W (43.1 A?)  

Science Journals Connector (OSTI)

Near-optimum conditions for lasing in Ni-like W are calculated for a 90-?g/cm2 foil irradiated by a 2? (?=0.53 ?m), 2.3×1014-W/cm2, 550-ps trapezoidal pulse. The gain coefficient for the J=0–1, 4d-4p Ni-like transition at 43.1 A? is predicted to be 5.5 cm-1. The electron density and temperature are 2.5×1021 cm-3 and 860 eV at x-ray laser time.

S. Maxon; S. Dalhed; P. L. Hagelstein; R. A. London; B. J. MacGowan; M. D. Rosen; G. Charatis; G. Busch

1989-07-17T23:59:59.000Z

234

High-energy x-ray microscopy of laser-fusion plasmas at the National Ignition Facility  

SciTech Connect (OSTI)

Multi-keV x-ray microscopy will be an important laser-produced plasma diagnostic at future megajoule facilities such as the National Ignition Facility (NIF).In preparation for the construction of this facility, we have investigated several instrumentation options in detail, and we conclude that near normal incidence single spherical or toroidal crystals may offer the best general solution for high-energy x-raymicroscopy at NIF and at similar large facilities. Kirkpatrick-Baez microscopes using multi-layer mirrors may also be good secondary options, particularly if apertures are used to increase the band-width limited field of view.

Koch, J.A.; Landen, O.L.; Hammel, B.A. [and others

1997-08-26T23:59:59.000Z

235

Saturated Amplification of a Collisionally Pumped Optical-Field-Ionization Soft X-Ray Laser at 41.8 nm  

Science Journals Connector (OSTI)

We report the first saturated amplification of an optical-field-ionization soft x-ray laser. The amplifying medium is generated by focusing a circularly polarized 330-mJ, 35-fs, 10-Hz Ti:sapphire laser system in a few-mm cell filled with xenon. A gain of 67 cm -1 on the 4d95p-4d95d transition at 41.8 nm in Pd-like xenon and a gain-length product of 15 have been inferred at saturation. This source delivers about 5×109 photons per pulse. The influence of the pumping energy and the laser polarization on the lasing output are also presented.

S. Sebban; R. Haroutunian; Ph. Balcou; G. Grillon; A. Rousse; S. Kazamias; T. Marin; J. P. Rousseau; L. Notebaert; M. Pittman; J. P. Chambaret; A. Antonetti; D. Hulin; D. Ros; A. Klisnick; A. Carillon; P. Jaeglé; G. Jamelot; J. F. Wyart

2001-04-02T23:59:59.000Z

236

VOLUME 81, NUMBER 26 P H Y S I C A L R E V I E W L E T T E R S 28 DECEMBER 1998 Demonstration of a High Average Power Tabletop Soft X-Ray Laser  

E-Print Network [OSTI]

of a High Average Power Tabletop Soft X-Ray Laser B. R. Benware, C. D. Macchietto, C. H. Moreno, and J. J of a high average power tabletop soft x-ray laser. An average laser output power of 1 mW .2 3 1014 photons of spontaneous emission in a plasma (an x-ray laser). At present, the generation of high order harmonics under

237

Imaging single cells in a beam of live cyanobacteria with an X-ray laser  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

This entry contains ten diffraction patterns, and reconstructions images, of individual living Cyanobium gracile cells, imaged using 517 eV X-rays from the LCLS XFEL. The Hawk software package was used for phasing. The Uppsala aerosol injector was used for sample injection, assuring very low noise levels. The cells come from various stages of the cell cycle, and were imaged in random orientations.

Schot, Gijs, vander

238

Laser-Plasma Acceleration of Electrons and Plasma Diagnostics at High Laser Fields  

E-Print Network [OSTI]

would open the prospect of building x-ray free-electron lasers and linear colliders hundreds of timesLaser-Plasma Acceleration of Electrons and Plasma Diagnostics at High Laser Fields Mike Downer: Laser-plasma acceleration is now entering an era of petawatt lasers, tenuous plasmas and multi

Shvets, Gennady

239

Self-field effects on instability of wave modes in a two-stream free-electron laser with an axial magnetic field  

SciTech Connect (OSTI)

Free electron lasers (FEL) play major roles in the Raman Regime, due to the charge and current densities of the beam self-field. The method of perturbation has been applied to study the influence of self-electric and self-magnetic fields. A dispersion relation for two-stream free electron lasers with a helical wiggler and an axial magnetic field has been found. This dispersion relation is solved numerically to investigate the influence of self-fields on the FEL coupling and the two-stream instability. It was found that self-fields can produce very large effects on the FEL coupling, but they have almost negligible effects on two-stream instability.

Mohsenpour, Taghi, E-mail: mohsenpour@umz.ac.ir; Rezaee Rami, Omme Kolsoum [Department of Physics, Faculty of Basic Sciences, University of Mazandaran, Babolsar (Iran, Islamic Republic of)

2014-07-15T23:59:59.000Z

240

Mode couplings in a two-stream free-electron laser with a helical wiggler and an ion-channel guiding  

SciTech Connect (OSTI)

In this study, the method of perturbation has been applied to obtain the dispersion relation (DR) of a two-stream free-electron laser (FEL) with a helical wiggler and an ion-channel with all relativistic effects on waves. This DR has been solved numerically to find the unstable modes and their growth rate. Numerical solutions of DR show that the growth rate is considerably enhanced in comparison with single-stream free-electron laser. In group II orbits, with relatively large wiggler induced velocities, new couplings are found. The effect of the velocity difference of the two electron beams on the instabilities has also been investigated in this study. Moreover, the effect of the ion-channel density on the maximum growth rate of FEL resonance has been analyzed.

Mohsenpour, Taghi, E-mail: mohsenpour@umz.ac.ir; Alirezaee, Hajar [Department of Physics, Faculty of Basic Sciences, University of Mazandaran, Babolsar (Iran, Islamic Republic of)

2014-08-15T23:59:59.000Z

Note: This page contains sample records for the topic "x-ray free-electron laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Optics-free x-ray FEL oscillator  

SciTech Connect (OSTI)

There is a need for an Optics-Free FEL Oscillators (OFFELO) to further the advantages of free-electron lasers and turning them in fully coherent light sources. While SASE (Self-Amplified Spontaneous Emission) FELs demonstrated the capability of providing very high gain and short pulses of radiation and scalability to the X-ray range, the spectra of SASE FELs remains rather wide ({approx}0.5%-1%) compared with typical short wavelengths FEL-oscillators (0.01%-0.0003% in OK-4 FEL). Absence of good optics in VUV and X-ray ranges makes traditional oscillator schemes with very high average and peak spectral brightness either very complex or, strictly speaking, impossible. In this paper, we discuss lattice of the X-ray optics-free FEL oscillator and present results of initial computer simulations of the feedback process and the evolution of FEL spectrum in X-ray OFFELO. We also discuss main limiting factors and feasibility of X-ray OFFELO.

Litvinenko, V.N.; Hao, Y.; Kayran, D.; Trbojevic, D.

2011-03-28T23:59:59.000Z

242

Measurements of Ionic Structure in Shock Compressed Lithium Hydride from Ultrafast X-Ray Thomson Scattering  

SciTech Connect (OSTI)

We present the first ultrafast temporally, spectrally, and angularly resolved x-ray scattering measurements from shock-compressed matter. The experimental spectra yield the absolute elastic and inelastic scattering intensities from the measured density of free electrons. Laser-compressed lithium-hydride samples are well characterized by inelastic Compton and plasmon scattering of a K-alpha x-ray probe providing independent measurements of temperature and density. The data show excellent agreement with the total intensity and structure when using the two-species form factor and accounting for the screening of ion-ion interactions.

Kritcher, A. L. [L-399, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551 (United States); Department of Nuclear Engineering, University of California Berkeley, Berkeley, California 94709 (United States); Neumayer, P.; Doeppner, T.; Landen, O. L.; Glenzer, S. H. [L-399, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551 (United States); Brown, C. R. D. [Department of Physics, Imperial College, London SW7 2AZ (United Kingdom); AWE plc., Aldermaston, Reading, RG7 4PR (United Kingdom); Davis, P. [L-399, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551 (United States); Department of Physics, University of California Berkeley, Berkeley, California 94709 (United States); Falcone, R. W.; Lee, H. J. [Department of Physics, University of California Berkeley, Berkeley, California 94709 (United States); Gericke, D. O.; Vorberger, J.; Wuensch, K. [CFSA, Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom); Gregori, G. [Department of Physics, Oxford University, Oxford OX1 3PU (United Kingdom); Holst, B.; Redmer, R. [Universitaet Rostock, Institut fuer Physik, D-18051 Rostock (Germany); Morse, E. C. [Department of Nuclear Engineering, University of California Berkeley, Berkeley, California 94709 (United States); Pelka, A.; Roth, M. [Institut fuer Kernphysik, Technische Universitaet Darmstadt, Darmstadt (Germany)

2009-12-11T23:59:59.000Z

243

X-ray spectroscopy study of electronic structure of laser-irradiated Au nanoparticles in a silica film  

SciTech Connect (OSTI)

The electronic structure of gold nanoparticles embedded in a silica film is studied, both before and after irradiation at 355 nm by a laser. The Au 5d occupied valence states are observed by x-ray emission spectroscopy. They show that before irradiation the gold atoms are in metallic states within the nanoparticles. After irradiation with a fluence of 0.5 J/cm{sup 2}, it is found that gold valence states are close to those of a metal-poor gold silicide; thanks to a comparison of the experimental Au 5d states with the calculated ones for gold silicides using the density-functional theory. The formation of such a compound is driven by the diffusion of the gold atoms into the silica film upon the laser irradiation. At higher fluence, 1 J/cm{sup 2}, we find a higher percentage of metallic gold that could be attributed to annealing in the silica matrix.

Jonnard, P.; Bercegol, H.; Lamaignere, L.; Morreeuw, J.-P.; Rullier, J.-L.; Cottancin, E.; Pellarin, M. [Laboratoire de Chimie Physique-Matiere et Rayonnement, Universite Pierre et Marie Curie, Centre National de la Recherche Scientifique Unite Mixte de Recherche (CNRS UMR) 7614, 11 rue Pierre et Marie Curie, F-75231 Paris Cedex 05 (France); Commissariat a l'Energie Atomique/Centre d'Etudes Scientifiques et Techniques d'Aquitaine (CEA/CESTA), BP 2, F-33114, Le Barp (France); Centre Agregat Laboratoire de Spectrometrie Ionique et Moleculaire (LASIM) et Laboratoire de Physique de la Matiere Condensee et Nanostructures (LPMCN), Universite Claude Bernard Lyon I, F-69622 Villeurbanne (France)

2005-03-15T23:59:59.000Z

244

Characterisation of a MeV Bremsstrahlung x-ray source produced from a high intensity laser for high areal density object radiography  

SciTech Connect (OSTI)

Results of an experiment to characterise a MeV Bremsstrahlung x-ray emission created by a short (<10 ps) pulse, high intensity (1.4 × 10{sup 19} W/cm{sup 2}) laser are presented. X-ray emission is characterized using several diagnostics; nuclear activation measurements, a calibrated hard x-ray spectrometer, and dosimeters. Results from the reconstructed x-ray energy spectra are consistent with numerical simulations using the PIC and Monte Carlo codes between 0.3 and 30 MeV. The intense Bremsstrahlung x-ray source is used to radiograph an image quality indicator (IQI) heavily filtered with thick tungsten absorbers. Observations suggest that internal features of the IQI can be resolved up to an external areal density of 85 g/cm{sup 2}. The x-ray source size, inferred by the radiography of a thick resolution grid, is estimated to be approximately 400 ?m (full width half maximum of the x-ray source Point Spread Function)

Courtois, C.; Compant La Fontaine, A.; Bazzoli, S.; Bourgade, J. L.; Gazave, J.; Lagrange, J. M.; Landoas, O.; Dain, L. Le; Pichoff, N. [CEA, DAM, DIF, F-91297 Arpajon (France)] [CEA, DAM, DIF, F-91297 Arpajon (France); Edwards, R.; Aedy, C. [AWE Plc., Aldermaston, Reading RG7 4PR (United Kingdom)] [AWE Plc., Aldermaston, Reading RG7 4PR (United Kingdom); Mastrosimone, D.; Pien, G.; Stoeckl, C. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States)] [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States)

2013-08-15T23:59:59.000Z

245

Role of multilayer-like interference effects on the transient optical response of Si{sub 3}N{sub 4} films pumped with free-electron laser pulses  

SciTech Connect (OSTI)

X-ray/optical cross-correlation methods are attracting increasing interest for exploring transient states of matter using ultrashort free-electron laser (FEL) pulses. Our paper shows that in such studies the difference in the penetration depth of the FEL-pump and the infrared (IR) probe pulses become important, in particular, when exploring the changes in the optical properties of solid targets. We discuss the role of interference effects, using a phenomenological model with excited and unperturbed slabs. The reliability of this model was experimentally verified by measuring the transient optical response of free-standing and silicon (Si) supported silicon nitride (Si{sub 3}N{sub 4}) films, simultaneously in reflection and transmission, using s- and p-polarized IR light. The changes in the Si{sub 3}N{sub 4} optical refractive index, induced by the FEL pulses, have fully been described in the frame of the proposed model. The experimental results confirm that the differences, observed in the FEL-induced transient reflectance and transmittance of the Si{sub 3}N{sub 4} targets with different thicknesses, arise from multilayer-like interferometric phenomena.

Casolari, F.; Giangrisostomi, E. [Elettra-Sincrotrone Trieste, SS 14 - km 163.5, I-34149 Basovizza, Trieste (Italy); Dipartimento di Fisica, Università degli Studi di Trieste, via A. Valerio 2, I-34127 Trieste (Italy); Bencivenga, F.; Capotondi, F.; Manfredda, M.; Pedersoli, E.; Principi, E.; Masciovecchio, C.; Kiskinova, M. [Elettra-Sincrotrone Trieste, SS 14 - km 163.5, I-34149 Basovizza, Trieste (Italy); Mincigrucci, R. [Elettra-Sincrotrone Trieste, SS 14 - km 163.5, I-34149 Basovizza, Trieste (Italy); Dipartimento di Fisica, Università degli Studi di Perugia, via A. Pascoli, I-06123 Perugia (Italy)

2014-05-12T23:59:59.000Z

246

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

SciTech Connect (OSTI)

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??m 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.

Tu, Shao-yong [Department of Modern Physics and CAS Key Laboratory of Geospace Environment, University of Science and Technology of China, Hefei, Anhui 230026 (China) [Department of Modern Physics and CAS Key Laboratory of Geospace Environment, University of Science and Technology of China, Hefei, Anhui 230026 (China); Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang, Sichuan 621900 (China); Hu, Guang-yue, E-mail: gyhu@ustc.edu.cn; Zhao, Bin; Zheng, Jian [Department of Modern Physics and CAS Key Laboratory of Geospace Environment, University of Science and Technology of China, Hefei, Anhui 230026 (China)] [Department of Modern Physics and CAS Key Laboratory of Geospace Environment, University of Science and Technology of China, Hefei, Anhui 230026 (China); Miao, Wen-yong; Yuan, Yong-teng; Zhan, Xia-yu; Hou, Li-fei; Jiang, Shao-en; Ding, Yong-kun [Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang, Sichuan 621900 (China)] [Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang, Sichuan 621900 (China)

2014-04-15T23:59:59.000Z

247

Sub-Picosecond X-Ray Pulses Workshop  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

International Workshop on the Interactions of Intense Sub-Picosecond X-Ray International Workshop on the Interactions of Intense Sub-Picosecond X-Ray Pulses with Matter (SLAC, January 23-24, 1997) During the last five years studies have been conducted at the Stanford Linear Accelerator Center (SLAC) and the Deutsches Elektronen-Synchrotron (DESY) in Hamburg concerning the feasibility of driving an Angstrom-wavelength Free-Electron Laser (FEL) with a high energy rf linac. Recent promising advances in linac, rf gun, and insertion device technologies make it seem likely that such a device can be constructed. The output radiation predicted for this type of source will be characterized by full transverse coherence, extreme pulse brevity (~50-100 fs), high peak power (10-100 GW), and very high unfocused peak power density (0.4-4.1013

248

Temporal synchronization of GHz repetition rate electron and laser pulses for the optimization of a compact inverse-Compton scattering x-ray source  

E-Print Network [OSTI]

The operation of an inverse-Compton scattering source of x-rays or gamma-rays requires the precision alignment and synchronization of highly focused electron bunches and laser pulses at the collision point. The arrival times of electron and laser pulses must be synchronized with picosecond precision. We have developed an RF synchronization technique that reduces the initial timing uncertainty from 350 ps to less than 2 ps, greatly reducing the parameter space to be optimized while commissioning the x-ray source. We describe the technique and present measurements of its performance.

Hadmack, Michael R; Madey, John M J; Kowalczyk, Jeremy M D

2014-01-01T23:59:59.000Z

249

The Next Challenge in X-Ray Science: Control of Resonant Electronic  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

The Next Challenge in X-Ray Science: Control of Resonant Electronic The Next Challenge in X-Ray Science: Control of Resonant Electronic Processes Wednesday, September 11, 2013 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Joachim Stöhr, LCLS My talk will give a historic perspective of the revolutionary science that was enabled by the advent of high power sources of coherent electromagnetic radiation and the implications for future scientific opportunities with x-ray free electron lasers (X-FELs). The historical journey starts with the development of radar microwave sources in the 1940s that fueled the development of nuclear magnetic resonance (NMR) techniques which by now have led to 6 Nobel Prizes. The theoretical description of NMR as coherent processes between nuclear states by Rabi and Bloch also provided the theoretical basis for the optical laser and its applications. Over the last

250

The BErkeley Lab Laser Accelerator (BELLA): A 10 GeV Laser Plasma Accelerator  

E-Print Network [OSTI]

used at the world's first x-ray free electron laser (FEL) at the LCLS at SLAC, and the lower energyThe BErkeley Lab Laser Accelerator (BELLA): A 10 GeV Laser Plasma Accelerator W.P. Leemansa,b,c , R, USA Abstract. An overview is presented of the design of a 10 GeV laser plasma accelerator (LPA

Geddes, Cameron Guy Robinson

251

Femtosecond electron and x-ray generation by laser and plasma-based sources  

E-Print Network [OSTI]

Although conventional electron sources (photocathode orof these conventional electron sources. Novel schemes which11, 2000 These laser-electron beam sources o?er some unique

Esarey, E.; Leemans, W.P.

2000-01-01T23:59:59.000Z

252

Narrowband inverse Compton scattering x-ray sources at high laser intensities  

E-Print Network [OSTI]

Narrowband x- and gamma-ray sources based on the inverse Compton scattering of laser pulses suffer from a limitation of the allowed laser intensity due to the onset of nonlinear effects that increase their bandwidth. It has been suggested that laser pulses with a suitable frequency modulation could compensate this ponderomotive broadening and reduce the bandwidth of the spectral lines, which would allow to operate narrowband Compton sources in the high-intensity regime. In this paper we, therefore, present the theory of nonlinear Compton scattering in a frequency modulated intense laser pulse. We systematically derive the optimal frequency modulation of the laser pulse from the scattering matrix element of nonlinear Compton scattering, taking into account the electron spin and recoil. We show that, for some particular scattering angle, an optimized frequency modulation completely cancels the ponderomotive broadening for all harmonics of the backscattered light. We also explore how sensitive this compensation ...

Seipt, D; Surzhykov, A; Fritzsche, S

2014-01-01T23:59:59.000Z

253

Pulsed CO{sub 2} laser with an X-ray preioniser based on a high-voltage low-pressure glow discharge  

SciTech Connect (OSTI)

An X-ray preioniser with an electron beam energy density of 0.1 J cm{sup -2} based on a high-voltage (20 - 40 kV) low-pressure glow discharge is developed for repetitively pulsed gas lasers. The electron concentration in the CO{sub 2} - N{sub 2} - He mixture as a function of the voltage across the preioniser is calculated for titanium and other foils. The preioniser can be operated both in a single-pulse regime and at pulse repetition rates ranging up to hundreds of Hertz. A specific energy yield of 51 J L{sup -1} is achieved in the X-ray preionised pulsed CO{sub 2} atmospheric-pressure laser. This preioniser was shown to be efficient for other active media (CO and excimer lasers), which opens up new opportunities for the development of repetitively pulsed gas lasers. (lasers)

Oreshkin, V F; Seregin, Aleksandr M; Sinaiskii, V V; Shchetinkina, T A ['Astrofizika' Research and Production Association (Russian Federation); Sorokin, A R [Institute of Semiconductor Physics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk (Russian Federation)

2003-12-31T23:59:59.000Z

254

Demonstration of an 8.85 nm Gain-Saturated Table-Top Soft X-Ray Laser and Lasing down to 7.4 nm  

SciTech Connect (OSTI)

We report the efficient generation of a gain-saturated 8.85 nm wavelength table-top soft x-ray laser operating at 1 Hz repetition rate and the observation of lasing at wavelengths as short as 7.36 nm in lanthanide ions.

Wang, Yong [Colorado State University, Fort Collins; Alessi, David [Colorado State University, Fort Collins; Luther, Brad [Colorado State University, Fort Collins; Yin, Liang [Colorado State University, Fort Collins; Martz, Dale [Colorado State University, Fort Collins; Berrill, Mark A [ORNL; Jorge, Rocca [Colorado State University, Fort Collins

2012-01-01T23:59:59.000Z

255

Single photon ionization of van der Waals clusters with a soft x-ray laser: ,,CO2...n and ,,CO2...n,,H2O...m  

E-Print Network [OSTI]

Single photon ionization of van der Waals clusters with a soft x-ray laser: ,,CO2...n and ,,CO2...n 2006; published online 20 October 2006 Pure neutral CO2 n clusters and mixed CO2 n H2O m clustersV. The distribution of pure CO2 n clusters decreases roughly exponentially with increasing cluster size. During

Rocca, Jorge J.

256

Beam Line Design and Beam Physics Study of Energy Recovery Linac Free Electron Laser at Peking University  

SciTech Connect (OSTI)

Energy recovering linac (ERL) offers an attractive alternative for generating intense beams of charged particles by approaching the operational efficiency of a storage ring while maintaining the superior beam quality typical of a linear accelerator. In ERLs, the decelerated beam cancels the beam loading effects of the accelerated beam with high repetition rate. Therefore, ERLs can, in principle, accelerate very high average currents with only modest amounts of RF power. So the efficiency of RF power to beam is much higher. Furthermore, the energy of beam to dump is lower, so it will reduce dump radiation. With the successful experiments in large maximum-to-injection energy ratio up to 51:1 and high power FEL up to 14kW, the use of ERL, especially combining with superconducting RF technology, provides a potentially powerful new paradigm for generation of the charged particle beams used in MW FEL, synchrotron radiation sources, high-energy electron cooling devices and so on. The 3+1/2 DC-SC photo injector and two 9cell TESLA superconducting cavity for IR SASE FEL in PKU provides a good platform to achieve high average FEL with Energy Recovery. The work of this thesis is on Beam line design and Beam dynamics study of Energy Recovery Linac Free Electron Laser for Peking University. It is the upgrade of PKU facility, which is under construction. With ERL, this facility can work in CW mode, so it can operate high average beam current without RF power constraint in main linac and generate high average FEL power. Moreover, it provides a test facility to study the key technology in ERL. System parameters are optimized for PKU ERL-FEL. The oscillation FEL output power is studied with different bunch charge, transverse emittance, bunch length and energy spread. The theory of optimal RF power and Q{sub ext} with ERL and without ERL is analyzed and applied to PKU injector and linac including microphonic effect. pace charge effect in the injector and merger is studied for beam energy at ~5MeV. Simulation shows that in the 3+1/2 DC- C injector, there is a region the beam could be over focused by RF electromagnetic field and the transverse emittance in the transport line up to linac will increase instantly due to over focusing. In order to eliminate this effect on beam emittance, several solutions are investigated to avoid over focusing. This result is very important for beam loading experiment for low bunch charge operation. Meanwhile, different merger structures are compared in terms of error sensitivity and emittance increase with space charge effect. In recirculation beam line, a new symmetric 180{degree} arc structure is designed. It fulfills the achromatic condition and adjustable bunch compression. These two parameters are controlled by different Quads knob. With this novel structure, the recirculation lattice can achieve path length adjustment, bunch compression and decompression in a large range. With beamline error, the beam central orbit will deviate from the designed trajectory. An orbit correction system is optimized, which balances between cost and performance of orbit after correction at design level. Different methods are used to estimate its robustness. The BBU instability, especially multi-pass BBU imposed a potentially severe limitation to the average current that can be accelerated in an ERL. Simulation gives the harmful HOMs and predicts that the threshold average current in this machine is much higher than the possible operation current. This work is based on the existing facility in PKU, so it provides guidelines for the facility operation and upgrade in the future. The theoretical analysis of ERL requirement and FEL requirement on beam transport line and beam property paves the way for future ERL research.

Guimei Wang

2011-12-31T23:59:59.000Z

257

Magnetism studies using resonant, coherent, x-ray scattering...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Magnetism studies using resonant, coherent, x-ray scattering Monday, September 10, 2012 - 10:00am SLAC, Bldg. 137, Room 226 Keoki Seu Seminar: With the advent of free electron...

258

Advances in understanding the anomalous dispersion of plasmas in the X-ray regime  

SciTech Connect (OSTI)

Over the last several years we have predicted and observed plasmas with an index of refraction greater than one in the soft X-ray regime. These plasmas are usually a few times ionized and have ranged from low-Z carbon plasmas to mid-Z tin plasmas. Our main computational tool has been the average atom code AVATOMKG that enables us to calculate the index of refraction for any plasma at any wavelength. In the last year we have improved this code to take into account many-atomic collisions. This allows the code to converge better at low frequencies. In this paper we present our search for plasmas with strong anomalous dispersion that could be used in X-ray laser interferometer experiments to help understand this phenomena. We discuss the calculations of anomalous dispersion in Na vapor and Ne plasmas near 47 nm where we predict large effects. We also discuss higher Z plasmas such as Ce and Yb plasmas that look very interesting near 47 nm. With the advent of the FLASH X-ray free electron laser in Germany and the LCLS X-FEL coming online at Stanford in another year we use the average atom code to explore plasmas at higher X-ray energy to identify potential experiments for the future. In particular we look near the K shell lines of near solid carbon plasmas and predict strong effects. During the next decade X-ray free electron lasers and other X-ray sources will be available to probe a wider variety of plasmas at higher densities and shorter wavelengths so understanding the index of refraction in plasmas will be even more essential.

Nilsen, J; Cheng, K T; Johnson, W R

2008-09-24T23:59:59.000Z

259

Spectroscopic investigations of hard x-ray emission from 120 ps laser-produced plasmas at intensities near 10{sup 17} W cm{sup {minus}2}  

SciTech Connect (OSTI)

Spectroscopic investigations of the x-ray emission of plasmas heated by 120 ps, frequency doubled pulses from the JANUS Nd: glass laser are presented. High Z K-shell spectra emitted from slab targets heated to near 10{sup 17} W cm{sup {minus}2} intensity are investigated. High resolution ({gamma}/{Delta}{gamma}>5000) x-ray spectra of multicharged ions of H-like Ti, Co, Ni, Cu, and also H-like Sc in the spectral range 1.5--3.0 {angstrom} are obtained in single laser shots using a spherically bent Mica crystal spectrograph with a 186 mm radius of curvature. The spectra- have one dimensional spatial resolution of about 25{mu}m and indicate that the size of the emission zone of the resonance, transitions is <25{mu}m. Simultaneous x-ray images of the plasma from a charge-coupled device pinhole camera confirmed that the plasma x-ray emission is from a similar sized source. Survey spectra {gamma}/{Delta}{gamma}=500--1000) taken with a flat LiF (200) crystal spectrometer with a charge-coupled device detector complement the high resolution data. Two dimensional LASNEX modeling of the laser target conditions indicate that the high K-shell charge states are produced in the hot dense region of the plasma with electron temperature >2 keV and density{approximately}10{sup 22} cm{sup {minus}3}. These experiments demonstrate that with modest laser energy, plasmas heated by high-intensity 120 ps lasers provide a very bright source of hard {approximately}8 keV x-ray emission.

Dunn, J.; Young, B.K.F.; Osterheld, A.L.; Foord, M.E.; Walling, R.S.; Stewart, R.E. [Lawrence Livermore National Lab., CA (United States); Faenov, A.Y. [VINIFTRI, Mendeleevo, Moscow Region (Russian Federation)

1995-11-01T23:59:59.000Z

260

High-resolution X-ray characterization of mid-IR Al0.45Ga0.55As/GaAs Quantum Cascade Laser structures  

Science Journals Connector (OSTI)

Abstract In this paper, the X-ray diffraction profiles of Quantum Cascade Laser (QCL) structures have been investigated. The examined structures were grown by molecular beam epitaxy. The crystallographic characterization was carried out using high resolution X-ray diffractometer. The information about thickness of individual layers and periodicity of the structures was derived from simulation of diffraction profiles calculated using dynamical diffraction theory. The influence of interface roughness on the shape of satellite peaks was studied. The particular attention has been paid to the analysis of the broadening of satellite peaks. The presented results show that broadening is due to the variation of thickness of individual layers.

J. Kubacka-Traczyk; I. Sankowska; O.H. Seeck; K. Kosiel; M. Bugajski

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "x-ray free-electron laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Soft X-ray laser using pumping of 3P and 4P levels of He-like and H-like ions  

DOE Patents [OSTI]

X-ray laser method and apparatus for producing coherent radiation at, for example, energies of at least 40 eV, using Be-like Cr, N-like Ni, He-like Na, B-like Cr, Be-like Mn or similar multiply ionized species to pump appropriate high energy transitions in He-like or H-like N, O, F, C or rare gases, with associated laser transition gains of 4-50 cm.sup.-1.

Hagelstein, Peter L. (Livermore, CA)

1987-01-01T23:59:59.000Z

262

Soft x-ray laser using pumping of 3p and 4p levels of He-like and H-like ions  

DOE Patents [OSTI]

X-ray laser method and apparatus for producing coherent radiation at, for example, energies of at least 40 eV, using Be-like Cr, N-like Ni, He-like Na, B-like Cr, Be-like Mn or similar multiply ionized species to pump appropriate high energy transitions in He-like or H-like N, O, F, C or rare gases, with associated laser transition gains of 4 to 50 cm/sup -1/.

Hagelstein, P.L.

1985-07-05T23:59:59.000Z

263

Generation of iodine L-shell X-rays under excitation of large CF{sub 3}I clusters by femtosecond laser radiation  

SciTech Connect (OSTI)

The use of clusters of polyatomic molecules with a relatively low ionisation energy ({approx}10 eV) is proposed for the efficient production of X-ray radiation. We have observed for the first time the generation of characteristic X-ray radiation due to L transitions in iodine atoms under the high-intensity femtosecond laser irradiation of molecular CF{sub 3}I clusters, which were a small admixture to Ar carrier gas. The X-ray conversion efficiency amounts to {approx}10{sup -6} (for a yield of {approx}10{sup 7} photons per pulse), which is an order of magnitude higher than the efficiency we obtained in the case of argon clusters under comparable conditions. (letters)

Gordienko, Vyacheslav M; Dzhidzhoev, M S; Zhvaniya, I A; Pribytkov, Andrei V; Trubnikov, Dmitrii N; Fedorov, D O

2012-11-30T23:59:59.000Z

264

Highly efficient tabletop x-ray laser at ?=41.8 nm in Pd-like xenon pumped by optical-field ionization in a cluster jet  

Science Journals Connector (OSTI)

The atomic-kinetic calculations of gain at 41.8 nm in Pd-like xenon are performed. The interpretation of known experiments has proved that x-ray laser in Pd-like xenon is feasible in the extremely wide range of atomic densities: 1017 ? [Xe8+] ? 3?×?1019 cm?3. This result is due to the large cross sections (and rates) of level excitations in Pd-like xenon by electron impact. We propose a highly efficient tabletop x-ray laser pumped by optical-field ionization in a xenon cluster jet. The efficiency of ?0.5% is possible with a pump laser pulse energy of ?0.001 J and an intensity of ?1016 W/cm2.

E. P. Ivanova

2011-10-19T23:59:59.000Z

265

Relativistic self-focusing of ultra-high intensity X-ray laser beams in warm quantum plasma with upward density profile  

SciTech Connect (OSTI)

The results of a numerical study of high-intensity X-ray laser beam interaction with warm quantum plasma (WQP) are presented. By means of an upward ramp density profile combined with quantum factors specially the Fermi velocity, we have demonstrated significant relativistic self-focusing (RSF) of a Gaussian electromagnetic beam in the WQP where the Fermi temperature term in the dielectric function is important. For this purpose, we have considered the quantum hydrodynamics model that modifies refractive index of inhomogeneous WQPs with the inclusion of quantum correction through the quantum statistical and diffraction effects in the relativistic regime. Also, to better illustration of the physical difference between warm and cold quantum plasmas and their effect on the RSF, we have derived the envelope equation governing the spot size of X-ray laser beam in Q-plasmas. In addition to the upward ramp density profile, we have found that the quantum effects would be caused much higher oscillation and better focusing of X-ray laser beam in the WQP compared to that of cold quantum case. Our computational results reveal the importance of the use of electrons density profile and Fermi speed in enhancing self-focusing of laser beam.

Habibi, M., E-mail: habibi.physics@gmail.com [Young Researchers and Elite Club, Shirvan Branch, Islamic Azad University, Shirvan (Iran, Islamic Republic of); Ghamari, F. [Young Researchers and Elite Club, Khorramabad Branch, Islamic Azad University, Khorramabad (Iran, Islamic Republic of)

2014-05-15T23:59:59.000Z

266

Modeling energy dependence of the inner-shell x-ray emission produced by femtosecond-pulse laser irradiation of xenon clusters  

Science Journals Connector (OSTI)

We employ the Los Alamos suite of atomic physics codes to model the inner-shell x-ray emission spectrum of xenon and compare results with those obtained via high-resolution x-ray spectroscopy of xenon clusters irradiated by 30fs Ti:Sapphire laser pulses. We find that the commonly employed configuration-average approximation breaks down and significant spin-orbit splitting necessitates a detailed level accounting. We reproduce an interesting spectral trend for a series of experimental spectra taken with varying pulse energy for fixed pulse duration. To simulate the experimental measurements at increasing beam energies, we find that spectral modeling requires an increased hot electron fraction, but decreased atomic density and bulk electron temperature. We believe these latter conditions to be a result of partial cluster destruction due to the increased energy in the laser prepulse.

Timothy C. Berkelbach; James Colgan; Joseph Abdallah; Jr.; Anatoly Ya. Faenov; Tatiana A. Pikuz; Yuji Fukuda; Koichi Yamakawa

2009-01-14T23:59:59.000Z

267

Low-energy x-ray and electron physics and applications to diagnostics development for laser-produced plasma research. Final report, April 30, 1980-April 29, 1981  

SciTech Connect (OSTI)

This final report describes a collaborative extension of an ongoing research program in low-energy x-ray and electron physics into particular areas of immediate need for the diagnostics of plasmas as involved in laser-produced fusion research. It has been for the continued support for one year of a post-doctoral research associate and for three student research assistants who have been applied to the following specific efforts: (1) the continuation of our research on the absolute characterization of x-ray photocathode systems for the 0.1 to 10 keV photon energy region. The research results were applied collaboratively to the design, construction and calibration of photocathodes for time-resolved detection with the XRD and the streak and framing cameras; (2) the design, construction and absolute calibration of optimized, bolt-on spectrographs for the absolute measurement of laser-produced plasma spectra.

Henke, B.L.

1981-08-01T23:59:59.000Z

268

Modeling energy dependence of the inner-shell x-ray emission produced by femtosecond-pulse laser irradiation of xenon clusters  

SciTech Connect (OSTI)

We employ the Los Alamos suite of atomic physics codes to model the inner-shell x-ray emission spectrum of xenon and compare results with those obtained via high-resolution x-ray spectroscopy of xenon clusters irradiated by 30 fs Ti:Sa laser pulses. We find that the commonly employed configuration average approximation breaks down and significant spin-orbit splitting necessitates a detailed level accounting. Additionally, we reproduce an interesting spectral trend for a series of experimental spectra taken with varying pulse energy for fixed pulse duration. To simulate the experimental measurements at increasing beam energies, we find that spectral modeling requires an increased hot electron fraction, but decreased atomic density and bulk electron temperature. We believe these latter conditions to be a result of partial cluster destruction due to the increased energy in the laser prepulse.

Colgan, James P [Los Alamos National Laboratory

2008-01-01T23:59:59.000Z

269

Plasma Channel Diagnostic Based on Laser Centroid Oscillations  

E-Print Network [OSTI]

THz [4] to free electron laser (FEL) x-ray sources [5] and Thomson scattering gamma ray sources [6Plasma Channel Diagnostic Based on Laser Centroid Oscillations A. J. Gonsalves, K. Nakamura, C. Lin for measuring the properties of discharge-based plasma channels by monitoring the centroid location of a laser

Geddes, Cameron Guy Robinson

270

Soft X-ray laser using pumping of 3P and 4P levels of He-like and H-like ions  

DOE Patents [OSTI]

X-ray laser method and apparatus are disclosed for producing coherent radiation at, for example, energies of at least 40 eV, using Be-like Cr, N-like Ni, He-like Na, B-like Cr, Be-like Mn or similar multiply ionized species to pump appropriate high energy transitions in He-like or H-like N, O, F, C or rare gases, with associated laser transition gains of 4-50 cm[sup [minus]1]. 8 figs.

Hagelstein, P.L.

1987-04-21T23:59:59.000Z

271

Soft x-ray laser using pumping of 3P and 4P levels of He-like and H-like ions  

DOE Patents [OSTI]

X-ray laser method and apparatus for producing coherent radiation at, for example, energies of 40 to 189 eV, using Be-like Cr, N-like Ni, He-like Na, B-like Cr, Be-like Mn or similar multiply ionized species to pump appropriate high energy transitions in He-like or H-like rare gases or N, O, F, or C gases, with associated laser transition gains of 20 to 50 cm/sup -1/.

Hagelstein, P.

1982-03-26T23:59:59.000Z

272

The ALS X-Ray Streak Camera: Bringing the Ultrafast and Ultrasmall into  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

The ALS X-Ray Streak Camera: Bringing the Ultrafast and Ultrasmall into Focus Print The ALS X-Ray Streak Camera: Bringing the Ultrafast and Ultrasmall into Focus Print Studying the world of the ultrasmall and the ultrafast is at the frontier of scientific research. Two x-ray approaches can be used for ultrafast examinations. The first entails developing sources that have short x-ray pulses such as free-electron lasers and slicing sources, which will provide the ultrafast temporal information. The other approach is to develop a detector that is fast enough to resolve the ultrafast details of the dynamical processes. ALS researchers are taking the second path but adding a spatial resolution capability; that is, they are developing a high-speed x-ray streak camera with high spatial resolution to watch, in real time, the motion of the atoms in materials. So far, a temporal resolution of 233 fs and a spatial resolution of 10 mm have been demonstrated. This is the first time that such a high temporal resolution has been combined with high spatial resolution in a streak camera.

273

The ALS X-Ray Streak Camera: Bringing the Ultrafast and Ultrasmall into  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

The ALS X-Ray Streak Camera: Bringing the Ultrafast and Ultrasmall into Focus Print The ALS X-Ray Streak Camera: Bringing the Ultrafast and Ultrasmall into Focus Print Studying the world of the ultrasmall and the ultrafast is at the frontier of scientific research. Two x-ray approaches can be used for ultrafast examinations. The first entails developing sources that have short x-ray pulses such as free-electron lasers and slicing sources, which will provide the ultrafast temporal information. The other approach is to develop a detector that is fast enough to resolve the ultrafast details of the dynamical processes. ALS researchers are taking the second path but adding a spatial resolution capability; that is, they are developing a high-speed x-ray streak camera with high spatial resolution to watch, in real time, the motion of the atoms in materials. So far, a temporal resolution of 233 fs and a spatial resolution of 10 mm have been demonstrated. This is the first time that such a high temporal resolution has been combined with high spatial resolution in a streak camera.

274

The ALS X-Ray Streak Camera: Bringing the Ultrafast and Ultrasmall into  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

The ALS X-Ray Streak Camera: Bringing the Ultrafast and Ultrasmall into Focus Print The ALS X-Ray Streak Camera: Bringing the Ultrafast and Ultrasmall into Focus Print Studying the world of the ultrasmall and the ultrafast is at the frontier of scientific research. Two x-ray approaches can be used for ultrafast examinations. The first entails developing sources that have short x-ray pulses such as free-electron lasers and slicing sources, which will provide the ultrafast temporal information. The other approach is to develop a detector that is fast enough to resolve the ultrafast details of the dynamical processes. ALS researchers are taking the second path but adding a spatial resolution capability; that is, they are developing a high-speed x-ray streak camera with high spatial resolution to watch, in real time, the motion of the atoms in materials. So far, a temporal resolution of 233 fs and a spatial resolution of 10 mm have been demonstrated. This is the first time that such a high temporal resolution has been combined with high spatial resolution in a streak camera.

275

Transverse Coherence of the LCLS X-Ray Beam  

SciTech Connect (OSTI)

Self-amplifying spontaneous radiation free-electron lasers, such as the LCLS or the European X-FEL, rely on the incoherent, spontaneous radiation as the seed for the amplifying process. Though this method overcomes the need for an external seed source one drawback is the incoherence of the effective seed signal. The FEL process allows for a natural growth of the coherence because the radiation phase information is spread out within the bunch due to slippage and diffraction of the radiation field. However, at short wavelengths this spreading is not sufficient to achieve complete coherence. In this presentation we report on the results of numerical simulations of the LCLS X-ray FEL. From the obtained radiation field distribution the coherence properties are extracted to help to characterize the FEL as a light source.

Not Available

2010-12-01T23:59:59.000Z

276

A new spectrometer design for the x-ray spectroscopy of laser-produced plasmas with high (sub-ns) time resolution  

SciTech Connect (OSTI)

This paper describes a new type of x-ray crystal spectrometer, which can be used in combination with gated x-ray detectors to obtain spectra from laser-produced plasmas with a high (sub-ns) time resolution. The spectrometer consists of a convex, spherically bent crystal, which images individual spectral lines as perfectly straight lines across multiple, sequentially gated, strip detectors. Since the Bragg-reflected rays are divergent, the distance between detector and crystal is arbitrary, so that this distance can be appropriately chosen to optimize the experimental arrangement with respect to the detector parameters. The spectrometer concept was verified in proof-of-principle experiments by imaging the L?{sub 1}- and L?{sub 2}-lines of tungsten, at 9.6735 and 9.96150 keV, from a micro-focus x-ray tube with a tungsten target onto a two-dimensional pixilated Pilatus detector, using a convex, spherically bent Si-422 crystal with a radius of curvature of 500 mm.

Bitter, M., E-mail: bitter@pppl.gov; Hill, K. W.; Efthimion, P. C.; Delgado-Aparicio, L.; Pablant, N. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Lu, Jian [Department of Engineering, Chongqing University, Chongqing 400044 (China); Beiersdorfer, P.; Chen, Hui [Physics Division, Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

2014-11-15T23:59:59.000Z

277

‘Taking X-ray phase contrast imaging into mainstream applications’ and its satellite workshop ‘Real and reciprocal space X-ray imaging’  

Science Journals Connector (OSTI)

...presented Femtosecond X-ray lasers for imaging atomic structure...which he described X-ray laser-induced electronic ordering...characterization of targets for laser fusion experiments. Krist. Tech...1205396109 ) 20 Talbot, HF . 1836 Facts relating to...

2014-01-01T23:59:59.000Z

278

A technique has been developed to accurately align a laser beam through a plasma channel by minimizing the  

E-Print Network [OSTI]

for radiation sources ­ ranging from coherent THz to free electron laser (FEL) x-ray sources and ThomsonAbstract A technique has been developed to accurately align a laser beam through a plasma channel by minimizing the shift in laser centroid and angle at the channel outptut. If only the shift in centroid

Geddes, Cameron Guy Robinson

279

Detailed analysis of hollow ions spectra from dense matter pumped by X-ray emission of relativistic laser plasma  

SciTech Connect (OSTI)

X-ray emission from hollow ions offers new diagnostic opportunities for dense, strongly coupled plasma. We present extended modeling of the x-ray emission spectrum reported by Colgan et al. [Phys. Rev. Lett. 110, 125001 (2013)] based on two collisional-radiative codes: the hybrid-structure Spectroscopic Collisional-Radiative Atomic Model (SCRAM) and the mixed-unresolved transition arrays (MUTA) ATOMIC model. We show that both accuracy and completeness in the modeled energy level structure are critical for reliable diagnostics, investigate how emission changes with different treatments of ionization potential depression, and discuss two approaches to handling the extensive structure required for hollow-ion models with many multiply excited configurations.

Hansen, S. B., E-mail: sbhanse@sandia.gov, E-mail: anatolyf@hotmail.com [Sandia National Laboratories, Albuquerque, New Mexico 87123 (United States); Colgan, J.; Abdallah, J. [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Faenov, A. Ya., E-mail: sbhanse@sandia.gov, E-mail: anatolyf@hotmail.com [Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow 125412 (Russian Federation); Quantum Beam Science Directorate, Japan Atomic Energy Agency, Kyoto 619-0215 (Japan); Pikuz, S. A.; Skobelev, I. Yu. [Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow 125412 (Russian Federation)] [Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow 125412 (Russian Federation); Wagenaars, E.; Culfa, O.; Dance, R. J.; Tallents, G. J.; Rossall, A. K.; Woolsey, N. C. [York Plasma Institute, Department of Physics, University of York, York YO10 5DD (United Kingdom)] [York Plasma Institute, Department of Physics, University of York, York YO10 5DD (United Kingdom); Booth, N.; Lancaster, K. L. [Central Laser Facility, STFC Rutherford Appleton Laboratory, Didcot OX11 0QX (United Kingdom)] [Central Laser Facility, STFC Rutherford Appleton Laboratory, Didcot OX11 0QX (United Kingdom); Evans, R. G. [Department of Physics, Imperial College, London SW7 2AZ (United Kingdom)] [Department of Physics, Imperial College, London SW7 2AZ (United Kingdom); Gray, R. J.; McKenna, P. [SUPA, Department of Physics, University of Strathclyde, Glasgow G4 ONG (United Kingdom)] [SUPA, Department of Physics, University of Strathclyde, Glasgow G4 ONG (United Kingdom); Kaempfer, T.; Schulze, K. S. [Helmholtzinstitut Jena, Jena D-07743 (Germany)] [Helmholtzinstitut Jena, Jena D-07743 (Germany); Uschmann, I. [Helmholtzinstitut Jena, Jena D-07743 (Germany) [Helmholtzinstitut Jena, Jena D-07743 (Germany); Institut für Optik und Quantenelektronic, Friedrich-Schiller-Universität Jena, Max-Wien Platz 1, Jena, D-07743 (Germany); and others

2014-03-15T23:59:59.000Z

280

Diffractive imaging at large Fresnel number: Challenge of dynamic mesoscale imaging with hard x rays  

Science Journals Connector (OSTI)

Real materials have structure at both the atomic or crystalline scale as well as at interfaces and defects at the larger scale of grains. There is a need for the study of materials at the “mesoscale,” the scale at which subgranular physical processes and intergranular organization couple to determine microstructure, crucially impacting constitutive response at the engineering macroscale. Diffractive imaging using photons that can penetrate multiple grains of material would be a transformative technique for the study of the performance of materials in dynamic extremes. Thicker samples imply higher energy photons of shorter wavelength, and imaging of multiple grains implies bigger spot sizes. Such imaging requires the use of future planned and proposed hard x-ray free electron lasers (such as the European XFEL) to provide both the spatial coherence transverse to the large spots and the peak brilliance to provide the short illumination times. The result is that the Fresnel number of the system becomes large and is no longer in the Fraunhofer far-field limit. The interrelated issues of diffractive imaging at large Fresnel number are analyzed, including proof that diffractive imaging is possible in this limit and estimates of the signal-to-noise possible. In addition, derivation of the heating rates for brilliant pulses of x rays are presented. The potential and limitations on multiple dynamic images are derived. This paper will present a study of x-ray interactions with materials in this new regime of spatially coherent but relatively large mesoscale spots at very hard energies. It should provide the theory and design background for the experiments and facilities required to control materials in extreme environments, in particular for the next generation of very-hard-x-ray free electron lasers.

John L. Barber; Cris W. Barnes; Richard L. Sandberg; Richard L. Sheffield

2014-05-12T23:59:59.000Z

Note: This page contains sample records for the topic "x-ray free-electron laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

X-ray holography at Lawrence Livermore National Laboratory  

SciTech Connect (OSTI)

The x-ray holography program at the Lawrence Livermore National Laboratory has two principal goals: (1) the development of x-ray diffraction techniques for DNA sequence analysis and (2) the development of x-ray laser holography for structural analysis of intact biological cells and organelles. DNA sequence analysis will be accomplished by applying x-ray diffraction techniques to determine the ensemble average of the sequence of labels along the individual elements of crystalline DNA. X-ray laser holographic imaging will be accomplished by applying three dimensional x-ray holography to elucidate the structure of few hundred angstrom objects such as 300 {Angstrom} chromatin fibers, nuclear pores and nucleic acid replication complexes in living cells. Existing laboratory x-ray lasers will be utilized to produce flash x-ray holograms of the biological structures.

Trebes, J.; Annese, C.; Birdsall, D.; Brase, J.; Gray, J.; Lane, S.; London, R.; Matthews, D.; Peters, D.; Pinkel, D.; Stone, G.; Rapp, D.; Rosen, M.; Weier, U.; Yorkey, T.

1990-10-11T23:59:59.000Z

282

X-ray spectroscopy of buried layer foils irradiated with an ultra high intensity short pulse laser  

E-Print Network [OSTI]

the intensity of the ignition laser pulse is be at least 10fuel [19, 22]. Current ignition laser requirements mandatesShort pulse laser produced plasmas Fast Ignition guides much

Chen, Sophia Nan

2009-01-01T23:59:59.000Z

283

Femtosecond laser-induced modification of potassium-magnesium silicate glasses: An analysis of structural changes by near edge x-ray absorption spectroscopy  

SciTech Connect (OSTI)

The effects of femtosecond laser pulse irradiation on the glass structure of alkaline silicate glasses were investigated by x-ray absorption near edge structure spectroscopy using the beamline of the Physikalisch-Technische Bundesanstalt at the electron synchrotron BESSY II in Berlin (Germany) by analyzing the magnesium K-edge absorption peak for different laser fluences. The application of fluences above the material modification threshold (2.1 J/cm{sup 2}) leads to a characteristic shift of {approx}1.0 eV in the K-edge revealing a reduced ({approx}3%) mean magnesium bond length to the ligated oxygen ions (Mg-O) along with a reduced average coordination number of the Mg ions.

Seuthe, T.; Eberstein, M. [Fraunhofer-Institut fuer Keramische Technologien und Systeme (IKTS), Winterbergstrasse 28, 01277 Dresden (Germany); Hoefner, M.; Eichler, H. J.; Grehn, M. [Technische Universitaet Berlin, Institut fuer Optik und Atomare Physik, Strasse des 17. Juni 135, 10623 Berlin (Germany); Reinhardt, F. [Physikalisch-Technische Bundesanstalt (PTB), Abbestr. 2-12, 10587 Berlin (Germany); Tsai, W. J. [ITRI South, Industrial Technology Research Institute, 8 Gongyan Rd., Liu-jia District, Tainan City 73445, Taiwan (China); Bonse, J. [BAM Bundesanstalt fuer Materialforschung und - pruefung, Unter den Eichen 87, 12205 Berlin (Germany)

2012-05-28T23:59:59.000Z

284

Compression of powerful x-ray pulses to attosecond durations by stimulated Raman backscattering in plasmas  

E-Print Network [OSTI]

the possibility of using powerful x-ray sources for producing ultrahigh laser intensities. It might clarify how much the emerging mJ x-ray laser technologies 1 could compete with the emerging MJ optical laser the biggest of currently built lasers: Linac Coherent Light Source LCLS 1 in x-ray range and megajoule laser

285

Availability Performance and Considerations for LCLS X-Ray FEL at SLAC  

SciTech Connect (OSTI)

The Linac Coherent Light Source (LCLS) is an X-ray Free Electron Laser (FEL) facility located at the SLAC National Accelerator Laboratory. LCLS has been in operation since spring 2009, and it has completed its 3rd user run. LCLS is the first in its class of X-ray FEL user facilities, and presents different availability challenges compared to storage ring light sources. This paper presents recent availability performance of the FEL as well as factors to consider when defining the operational availability figure of merit for user runs. During LCLS [1] user runs, an availability of 95% has been set as a goal. In run III, LCLS photon and electron beam systems achieved availabilities of 94.8% and 96.7%, respectively. The total availability goal can be distributed among subsystems to track performance and identify areas that need attention in order to maintain and improve hardware reliability and operational availability. Careful beam time accounting is needed to understand the distribution of down time. The LCLS complex includes multiple experimental hutches for X-ray science, and each user program has different requirements of a set of parameters that the FEL can be configured to deliver. Since each user may have different criteria for what is considered 'acceptable beam', the quality of the beam must be considered to determine the X-ray beam availability.

Allen, W.B.; Brachmann, A.; Colocho, W.; Stanek, M.; Warren, J.; /SLAC; ,

2011-08-16T23:59:59.000Z

286

Chest x-Rays  

Broader source: Energy.gov [DOE]

The B-reading is a special reading of a standard chest x-ray film performed by a physician certified by the National Institute for Occupational Safety and Health (NIOSH). The reading looks for changes on the chest x-ray that may indicate exposure and disease caused by agents such as asbestos or silica.

287

X-ray binaries  

E-Print Network [OSTI]

We review the nuclear astrophysics aspects of accreting neutron stars in X-ray binaries. We summarize open astrophysical questions in light of recent observations and their relation to the underlying nuclear physics. Recent progress in the understanding of the nuclear physics, especially of X-ray bursts, is also discussed.

H. Schatz; K. E. Rehm

2006-08-01T23:59:59.000Z

288

THREE-DIMENSIONAL IMAGING OF NANOSCALE MATERIALS BY UISNG COHERENT X-RAYS  

SciTech Connect (OSTI)

X-ray crystallography is currently the primary methodology used to determine the 3D structure of materials and macromolecules. However, many nanostructures, disordered materials, biomaterials, hybrid materials and biological specimens are noncrystalline and, hence, their structures are not accessible by X-ray crystallography. Probing these structures therefore requires the employment of different approaches. A very promising technique currently under rapid development is X-ray diffraction microscopy (or lensless imaging), in which the coherent X-ray diffraction pattern of a noncrystalline specimen is measured and then directly phased to obtain a high-resolution image. Through the DOE support over the past three years, we have applied X-ray diffraction microscopy to quantitative imaging of GaN quantum dot particles, and revealed the internal GaN-Ga2O3 core shell structure in three dimensions. By exploiting the abrupt change in the scattering cross-section near electronic resonances, we carried out the first experimental demonstration of resonant X-ray diffraction microscopy for element specific imaging. We performed nondestructive and quantitative imaging of buried Bi structures inside a Si crystal by directly phasing coherent X-ray diffraction patterns acquired below and above the Bi M5 edge. We have also applied X-ray diffraction microscopy to nondestructive imaging of mineral crystals inside biological composite materials - intramuscular fish bone - at the nanometer scale resolution. We identified mineral crystals in collagen fibrils at different stages of mineralization and proposed a dynamic mechanism to account for the nucleation and growth of mineral crystals in the collagen matrix. In addition, we have also discovered a novel 3D imaging modality, denoted ankylography, which allows for complete 3D structure determination without the necessity of sample titling or scanning. We showed that when the diffraction pattern of a finite object is sampled at a sufficiently fine scale on the Ewald sphere, the 3D structure of the object is determined by the 2D spherical pattern. We confirmed the theoretical analysis by performing 3D numerical reconstructions of a sodium silicate glass structure at 2 Ã? resolution from a 2D spherical diffraction pattern alone. As X-ray free electron lasers are under rapid development worldwide, ankylography may open up a new horizon to obtain the 3D structure of a non-crystalline specimen from a single pulse and allow time-resolved 3D structure determination of disordered materials.

Jianwei Miao

2011-04-18T23:59:59.000Z

289

High Average Power, 100 Hz Repetition Rate, Table-top EUV/Soft X-ray Lasers  

SciTech Connect (OSTI)

Compact =13.9 nm and =18.9 nm lasers with >0.1 mW average power at 100 Hz repetition rate driven by a diode-pumped, 1 J, CPA laser were demonstrated. Wavelength scaling to =10.9 nm will be discussed.

Reagan, Brendon [Colorado State University, Fort Collins; Wernsing, Keith [Colorado State University, Fort Collins; Baumgarten, Cory [Colorado State University, Fort Collins; Durivage, Leon [Colorado State University, Fort Collins; Berrill, Mark A [ORNL; Furch, Federico [Colorado State University, Fort Collins; Curtis, Alden [Colorado State University, Fort Collins; Salsbury, Chase [Colorado State University, Fort Collins; Luther, Brad [Colorado State University, Fort Collins; Patel, Dinesh [Colorado State University, Fort Collins; Menoni, Carmen [Colorado State University, Fort Collins; Rocca, Jorge [Colorado State University, Fort Collins

2013-01-01T23:59:59.000Z

290

Compton backscattered collimated x-ray source  

DOE Patents [OSTI]

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.

Ruth, R.D.; Huang, Z.

1998-10-20T23:59:59.000Z

291

Compton backscattered collmated X-ray source  

DOE Patents [OSTI]

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.

Ruth, Ronald D. (Woodside, CA); Huang, Zhirong (Stanford, CA)

2000-01-01T23:59:59.000Z

292

Compton backscattered collimated x-ray source  

DOE Patents [OSTI]

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.

Ruth, Ronald D. (Woodside, CA); Huang, Zhirong (Stanford, CA)

1998-01-01T23:59:59.000Z

293

X-ray absorption spectroscopy  

E-Print Network [OSTI]

009-9473-8 REVIEW X-ray absorption spectroscopy Junko Yano Æand application of X-ray absorption spectroscopy, bothX-ray absorption near-edge structure (XANES) and extended X-

Yano, Junko; Yachandra, Vittal K.

2009-01-01T23:59:59.000Z

294

X-ray Absorption Spectroscopy  

E-Print Network [OSTI]

type: Review X-ray Absorption Spectroscopy Junko Yano andPhotosystem II; XAS, X-ray absorption spectroscopy; EXAFS,X-ray absorption fine structure; EPR, electron paramagnetic

Yano, Junko

2010-01-01T23:59:59.000Z

295

X-Ray Generators  

Science Journals Connector (OSTI)

There are many types of X-ray generators sold commercially. The following are some of ... that should be considered when selecting a particular generator for a particular purpose. All the companies listed below s...

Reuben Rudman

1972-01-01T23:59:59.000Z

296

Femtosecond X-ray diffraction from two-dimensional protein crystals  

Science Journals Connector (OSTI)

Bragg diffraction achieved from two-dimensional protein crystals using femtosecond X-ray laser snapshots is presented.

Frank, M.

2014-02-28T23:59:59.000Z

297

X-ray induced optical reflectivity  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

The change in optical reflectivity induced by intense x-ray pulses can now be used to study ultrafast many body responses in solids in the femtosecond time domain. X-ray absorption creates photoelectrons and core level holes subsequently filled by Auger or fluorescence processes, and these excitations ultimately add conduction and valence band carriers that perturb optical reflectivity.Optical absorption associated with band filling and band gap narrowing is shown to explain the basic features found in recent measurements on an insulator (silicon nitride, Si3N4), a semiconductor(gallium arsenide,GaAs), and a metal (gold,Au), obtained with ?100 fs x-ray pulses at 500-2000 eV and probed with 800 nm laser pulses. In particular GaAs exhibits an abrupt drop in reflectivity, persisting only for a time comparable to the x-ray excitation pulse duration, consistent with prompt band gap narrowing.

Durbin, Stephen M.

2012-01-01T23:59:59.000Z

298

HARMONIC CASCADE FEL DESIGNS FOR LUX, A FACILTY FOR ULTRAFAST X-RAY SCIENCE  

E-Print Network [OSTI]

-electron laser (FEL) beamlines which use the har- monic cascade approach to produce coherent XUV & soft X-ray for an integrated system of ultrafast x-ray techniques and lasers, using laser-seeded harmonic cascade FEL's, rfHARMONIC CASCADE FEL DESIGNS FOR LUX, A FACILTY FOR ULTRAFAST X-RAY SCIENCE J. Corlett, W. Fawley

Wurtele, Jonathan

299

Metal-like heat conduction in laser-excited InSb probed by picosecond time-resolved x-ray diffraction  

Science Journals Connector (OSTI)

A semiconductor (InSb) showed transient metal-like heat conduction after excitation of a dense electron-hole plasma via short and intense light pulses. A related ultrafast strain relaxation was detected using picosecond time-resolved x-ray diffraction. The deduced heat conduction was, by a factor of 30, larger than the lattice contribution. The anomalously high heat conduction can be explained once the contribution from the degenerate photocarrier plasma is taken into account. The magnitude of the effect could provide the means for guiding heat in semiconductor nanostructures. In the course of this work, a quantitative model for the carrier dynamics in laser-irradiated semiconductors has been developed, which does not rely on any adjustable parameters or ad hoc assumptions. The model includes various light absorption processes (interband, free carrier, two photon, and dynamical Burstein-Moss shifts), ambipolar diffusion, energy transport (heat and chemical potential), electrothermal effects, Auger recombination, collisional excitation, and scattering (elastic and inelastic). The model accounts for arbitrary degrees of degeneracy.

P. Sondhauss, O. Synnergren, T. N. Hansen, S. E. Canton, H. Enquist, A. Srivastava, and J. Larsson

2008-09-10T23:59:59.000Z

300

Characterization of the collisionally pumped optical-field-ionized soft-x-ray laser at 41.8nm driven in capillary tubes  

Science Journals Connector (OSTI)

We report on experimental and theoretical studies of a collisionally pumped, optical-field-ionized soft-x-ray laser (SXRL) at 41.8nm driven in capillary tubes with smooth inner surface. A detailed experimental study has been conducted in order to understand the key effects related to guiding in this configuration. The amplifying plasma was created inside few-cm-long capillary tubes, and maximum extreme ultraviolet emission was obtained when operating in a multimode guiding regime with an optimized lasing signal from a 25-mm-long capillary a factor of 3 higher than that of a gas cell and with a beam divergence reduced by a factor of 3. A numerical code, named COFIXE, has been developed to calculate the SXRL signal emitted by the plasma source. It includes the calculation of the pump beam propagation, the determination of the plasma state just after the interaction with the pump beam, the calculation of the evolution of the local properties of the plasma during the subsequent few ps, and the calculation of the amplification and transport of the SXRL emission. Excellent agreement has been obtained between experiment and theory for several features such as the divergence of the beam, the correlation between guided pump beam transmission and SXRL energy, and the enhancement factor induced by guiding.

B. Cros; T. Mocek; I. Bettaibi; G. Vieux; M. Farinet; J. Dubau; S. Sebban; G. Maynard

2006-03-02T23:59:59.000Z

Note: This page contains sample records for the topic "x-ray free-electron laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

X-ray beam finder  

DOE Patents [OSTI]

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.

Gilbert, H.W.

1983-06-16T23:59:59.000Z

302

Photonic laser-driven accelerator for GALAXIE  

SciTech Connect (OSTI)

We report on the design and development of an all-dielectric laser-driven accelerator to be used in the GALAXIE (GV-per-meter Acce Lerator And X-ray-source Integrated Experiment) project's compact free-electron laser. The approach of our working design is to construct eigenmodes, borrowing from the field of photonics, which yield the appropriate, highly demanding dynamics in a high-field, short wavelength accelerator. Topics discussed include transverse focusing, power coupling, bunching, and fabrication.

Naranjo, B.; Ho, M.; Hoang, P.; Putterman, S.; Valloni, A.; Rosenzweig, J. B. [UCLA Dept. of Physics and Astronomy Los Angeles, CA 90095-1547 (United States)

2012-12-21T23:59:59.000Z

303

X-ray Spectrometry  

Science Journals Connector (OSTI)

These provide excellent energy resolution for a wide range of X-ray energies, from the optical range up to several kiloelectronvolts. ... The Astro-E2 launched in 2005 was the first mission that contained a low-temperature microcalorimeter-based observatory, and three more low-temperature detector-based observatories are being developed (NeXT, Constellation-X, ZEUS). ...

Imre Szalóki; János Osán; René E. Van Grieken

2006-05-10T23:59:59.000Z

304

Time-resolved x-ray diagnostics  

SciTech Connect (OSTI)

Techniques for time-resolved x-ray diagnostics will be reviewed with emphasis on systems utilizing x-ray diodes or scintillators. System design concerns for high-bandwidth (> 1 GHz) diagnostics will be emphasized. The limitations of a coaxial cable system and a technique for equalizing to improve bandwidth of such a system will be reviewed. Characteristics of new multi-GHz amplifiers will be presented. An example of a complete operational system on the Los Alamos Helios laser will be presented which has a bandwidth near 3 GHz over 38 m of coax. The system includes the cable, an amplifier, an oscilloscope, and a digital camera readout.

Lyons, P.B.

1981-01-01T23:59:59.000Z

305

E-Print Network 3.0 - angle x-ray studies Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

work as a preionization source... of with and without applying x-ray photons to the HF laser. Since dose rate of the cw x-ray generator is easily Source: Ecole Polytechnique,...

306

X-rays only when you want them: Report on Pseudo-single-bunch...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Room 108A Speaker: David Robin, Lawrence Berkeley National Laboratory Program Description Laser pump - x-ray probe experiments require control over the x-ray pulse pattern and...

307

E-Print Network 3.0 - alpha tagged x-ray Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

-X-ray pinhole camera -Fast electron beam spatial distribution 5m... ? Fusion Energy Fast Ignition Optimisation high power laser-driven ion -Cu K-alpha imaging system -X-ray... and...

308

Spatiotemporal focusing dynamics in plasmas at X-ray wavelength  

SciTech Connect (OSTI)

Using a finite curvature beam, we investigate here the spatiotemporal focusing dynamics of a laser pulse in plasmas at X-ray wavelength. We trace the dependence of curvature parameter on the focusing of laser pulse and recognize that the self-focusing in plasma is more intense for the X-ray laser pulse with curved wavefront than with flat wavefront. The simulation results demonstrate that spatiotemporal focusing dynamics in plasmas can be controlled with the appropriate choice of beam-plasma parameters to explore the high intensity effects in X-ray regime.

Sharma, A., E-mail: a-physics2001@yahoo.com; Tibai, Z. [Institute of Physics, University of Pecs, Pecs–7624 (Hungary)] [Institute of Physics, University of Pecs, Pecs–7624 (Hungary); Hebling, J. [Institute of Physics, University of Pecs, Pecs–7624 (Hungary) [Institute of Physics, University of Pecs, Pecs–7624 (Hungary); Szentagothai Research Centre, University of Pecs, Pecs-7624 (Hungary); Mishra, S. K. [Institute for Plasma Research, Gandhinagar (India)] [Institute for Plasma Research, Gandhinagar (India)

2014-03-15T23:59:59.000Z

309

Tunable X-ray source  

DOE Patents [OSTI]

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.

Boyce, James R. (Williamsburg, VA)

2011-02-08T23:59:59.000Z

310

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

SciTech Connect (OSTI)

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

Du Yingchao; Yan Lixin; Hua Jianfei; Du Qiang; Zhang Zhen; Li Renkai; Qian Houjun; Huang Wenhui; Chen Huaibi; Tang Chuanxiang [Accelerator Laboratory, Department of Engineering Physics, Tsinghua University, Beijing 100084 (China); Key Laboratory of Particle and Radiation Imaging, Tsinghua University, Ministry of Education, Beijing 100084 (China); Key Laboratory of High Energy Radiation Imaging Fundamental Science for National Defense, Tsinghua University, Beijing 100084 (China)

2013-05-15T23:59:59.000Z

311

Damage of amorphous carbon induced by soft x-ray femtosecond pulses above and below the critical angle  

SciTech Connect (OSTI)

We present results of damage studies conducted at the Free Electron LASer in Hamburg (FLASH) facility with 13.5 nm (91.8 eV) and 7 nm (177.1 eV) radiations. The laser beam was focused on a sample of 890-nm-thick amorphous carbon coated on a silicon wafer mimicking a x-ray mirror. The fluence threshold for graphitization was determined for different grazing angles above and below the critical angle. The observed angular dependence of F{sub th} is explained by the variation in absorption depth and reflectivity. Moreover, the absorbed local dose needed for the phase transition leading to graphitization is shown to vary with the radiation wavelength.

Chalupsky, J.; Hajkova, V.; Burian, T.; Juha, L.; Vysin, L. [Institute of Physics, Academy of Sciences of the Czech Republic, Na Slovance 2, 182 21 Prague 8 (Czech Republic); Altapova, V.; Sinn, H.; Tschentscher, Th.; Gaudin, J. [European XFEL, DESY, Notkestr., 85 D-22607 Hamburg (Germany); Gleeson, A. J. [CCRLC Daresbury Laboratory, Warrington, Cheshire WA4 4AD (United Kingdom); Jurek, M.; Sobierajski, R. [Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, PL-02-668 Warsaw (Poland); Stoermer, M. [GKSS-Forschungszentrum Geesthacht GmbH, Max-Planck-Strasse, 1 21502 Geesthach (Germany); Tiedtke, K.; Toleikis, S.; Wabnitz, H. [HASYLAB/DESY, Notkestr., 85 D-22607 Hamburg (Germany)

2009-07-20T23:59:59.000Z

312

X-ray Spectrometry  

Science Journals Connector (OSTI)

The segmented STJ operated at total count rates of above 105 counts/s, and the best-achieved energy resolution of their single STJ was found to be 10 eV for X-ray energies below 1 keV. ... The Mo?Au TES, with an operating temperature of 230 mK, was developed for the Constellation-X mission and the energy resolution of the spectrometer is ?28 eV at 3.3 keV. ...

Imre Szalóki; Szabina B. Török; Jasna Injuk; René E. Van Grieken

2002-05-18T23:59:59.000Z

313

Ultrashort x-ray backlighters and applications  

SciTech Connect (OSTI)

Previously, using ultrashort laser pulses focused onto solid targets, we have experimentally studied a controllable ultrafast broadband radiation source in the extreme ultraviolet for time-resolved dynamical studies in ultrafast science [J. Workman, A. Maksimchuk, X. Llu, U. Ellenberger, J. S. Coe, C.-Y. Chien, and D. Umstadter, ``Control of Bright Picosecond X-Ray Emission from Intense Sub- Picosecond Laser-Plasma Interactions,`` Phys. Rev. Lett. 75, 2324 (1995)]. Once armed with a bright ultrafast broadband continuum x-ray source and appropriate detectors, we used the source as a backlighter to study a remotely produced plasma. The application of the source to a problem relevant to high-density matter completes the triad: creating and controlling, efficiently detecting, and applying the source. This work represented the first use of an ultrafast laser- produced x-ray source as a time-resolving probe in an application relevant to atomic, plasma and high-energy-density matter physics. Using the x-ray source as a backlighter, we adopted a pump-probe geometry to investigate the dynamic changes in electronic structure of a thin metallic film as it is perturbed by an ultrashort laser pulse. Because the laser deposits its energy in a skin depth of about 100 {Angstrom} before expansion occurs, up to gigabar pressure shock waves lasting picosecond in duration have been predicted to form in these novel plasmas. This raises the possibility of studying high- energy-density matter relevant to inertial confinement fusion (ICF) and astrophysics in small-scale laboratory experiments. In the past, time-resolved measurements of K-edge shifts in plasmas driven by nanosecond pulses have been used to infer conditions in highly compressed materials. In this study, we used 100-fs laser pulses to impulsively drive shocks into a sample (an untamped 1000 {Angstrom} aluminum film on 2000 {Angstrom} of parylene-n), measuring L-edge shifts.

Umstadter, D., University of Michigan

1997-08-01T23:59:59.000Z

314

Advances in X-Ray Chemical Analysis, Japan, 45 (2014) ISSN 0911-7806 Color Center in NaCl  

E-Print Network [OSTI]

. In addition, the color of NaCl changes to pale purple when irradiated with 405 nm laser after X-ray irradiation and to light brown when irradiated with 532 nm laser after X-ray irradiation. The colorCl, Sodium chloride, X-ray irradiation, Laser irradiation, White fluorescent lamp irradiation X X NaCl X X X

Jun, Kawai

315

State-of-the-art Thin Film X-ray Optics for Conventional Synchrotrons and FEL Sources  

SciTech Connect (OSTI)

Selected aspects of simulation, preparation and characterization of total reflection and multilayer X-ray optics will be discussed. The best multilayer is found by calculating the optical properties of the coating. Sophisticated improvements in deposition technology allow the precise realisation of the specified parameters when manufacturing the X-ray optics. The quality of the shape of the substrate for the optics is measured with the aid of profilometry. X-ray reflectometry measures both film thickness as well as their lateral gradient. Last but not least we will be showing results of the development of carbon coatings as total reflection mirrors for FEL (free electron laser) sources. Over the past years we have developed optimized optics for the XUV range up to 200 eV. First FEL irradiation tests have shown that carbon coatings offer high reflectivity >95%, high radiation stability, good uniformity in thickness and roughness. An optimized coating of two stripes for different beam energies was produced especially for a tomography beamline, where a Ru/C multilayer was chosen for energies between 10 and 22 keV and a W/Si multilayer for energies between 22 and 45 keV.

Wiesmann, Joerg; Mchaelsen, Carsten; Hertlein, Frank [Incoatec GmbH, Max-Planck-Strasse 2, 21502 Geesthacht (Germany); Stoermer, Michael [GKSS Research Center, Max-Planck-Strasse 1, 21502 Geesthacht (Germany); Seifert, Andreas [Carl Zeiss Laser Optics GmbH, Carl-Zeiss-Strasse 22, 73447 Oberkochen (Germany)

2007-01-19T23:59:59.000Z

316

KOTOBUKI-1 apparatus for cryogenic coherent X-ray diffraction imaging  

SciTech Connect (OSTI)

We have developed an experimental apparatus named KOTOBUKI-1 for use in coherent X-ray diffraction imaging experiments of frozen-hydrated non-crystalline particles at cryogenic temperature. For cryogenic specimen stage with small positional fluctuation for a long exposure time of more than several minutes, we here use a cryogenic pot cooled by the evaporation cooling effect for liquid nitrogen. In addition, a loading device is developed to bring specimens stored in liquid nitrogen to the specimen stage in vacuum. The apparatus allows diffraction data collection for frozen-hydrated specimens at 66 K with a positional fluctuation of less than 0.4 ?m and provides an experimental environment to easily exchange specimens from liquid nitrogen storage to the specimen stage. The apparatus was developed and utilized in diffraction data collection of non-crystalline particles with dimensions of ?m from material and biological sciences, such as metal colloid particles and chloroplast, at BL29XU of SPring-8. Recently, it has been applied for single-shot diffraction data collection of non-crystalline particles with dimensions of sub-?m using X-ray free electron laser at BL3 of SACLA.

Nakasako, Masayoshi; Takayama, Yuki; Oroguchi, Tomotaka; Sekiguchi, Yuki; Kobayashi, Amane [Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522 (Japan) [Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522 (Japan); RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Shirahama, Keiya [Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522 (Japan)] [Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522 (Japan); Yamamoto, Masaki; Hikima, Takaaki; Yonekura, Koji; Maki-Yonekura, Saori; Kohmura, Yoshiki; Inubushi, Yuichi [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan)] [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Takahashi, Yukio; Suzuki, Akihiro [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan) [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Department of Precision Science and Technology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan); Matsunaga, Sachihiro; Inui, Yayoi [Department of Applied Biological Science Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510 (Japan)] [Department of Applied Biological Science Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510 (Japan); Tono, Kensuke; Kameshima, Takashi; Joti, Yasumasa [Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5198 (Japan)] [Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5198 (Japan); Hoshi, Takahiko [Kohzu Precision Co., Ltd., 2-6-15 Kurigi, Aso-ku, Kawasaki, Kanagawa 215-8521 (Japan)] [Kohzu Precision Co., Ltd., 2-6-15 Kurigi, Aso-ku, Kawasaki, Kanagawa 215-8521 (Japan)

2013-09-15T23:59:59.000Z

317

X-ray Absorption Spectroscopy  

SciTech Connect (OSTI)

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.

Yano, Junko; Yachandra, Vittal K.

2009-07-09T23:59:59.000Z

318

X-ray fluorescence mapping  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

biololgical cells, over the measurement of impurities in solar cells, to the rare earth content of geological materials. A somewhat 'typical' layout for a X-ray fluorescence...

319

Burning plasmas with ultrashort soft-x-ray flashing  

SciTech Connect (OSTI)

Fast ignition with narrow-band coherent x-ray pulses has been revisited for cryogenic deuterium-tritium (DT) plasma conditions achieved on the OMEGA Laser System. In contrast to using hard-x-rays (hv = 3-6 keV) proposed in the original x-ray fast-ignition proposal, we find that soft-x-ray sources with hv Almost-Equal-To 500 eV photons can be suitable for igniting the dense DT-plasmas achieved on OMEGA. Two-dimensional radiation-hydrodynamics simulations have identified the break-even conditions for realizing such a 'hybrid' ignition scheme (direct-drive compression with soft-x-ray heating) with 50-{mu}m-offset targets: {approx}10 ps soft-x-ray pulse (hv Almost-Equal-To 500 eV) with a total energy of 500-1000 J to be focused into a 10 {mu}m spot-size. A variety of x-ray pulse parameters have also been investigated for optimization. It is noted that an order of magnitude increase in neutron yield has been predicted even with x-ray energy as low as {approx}50 J. Scaling this idea to a 1 MJ large-scale target, a gain above {approx}30 can be reached with the same soft-x-ray pulse at 1.65 kJ energy. Even though such energetic x-ray sources do not currently exist, we hope that the proposed ignition scheme may stimulate efforts on generating powerful soft-x-ray sources in the near future.

Hu, S. X.; Goncharov, V. N.; Skupsky, S. [Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623-1299 (United States)

2012-07-15T23:59:59.000Z

320

Human genome sequencing with direct x-ray holographic imaging  

SciTech Connect (OSTI)

Direct holographic imaging of biological materials is widely applicable to the study of the structure, properties and action of genetic material. This particular application involves the sequencing of the human genome where prospective genomic imaging technology is composed of three subtechnologies, name an x-ray holographic camera, suitable chemistry and enzymology for the preparation of tagged DNA samples, and the illuminator in the form of an x-ray laser. We report appropriate x-ray camera, embodied by the instrument developed by MCR, is available and that suitable chemical and enzymatic procedures exist for the preparation of the necessary tagged DNA strands. Concerning the future development of the x-ray illuminator. We find that a practical small scale x-ray light source is indeed feasible. This outcome requires the use of unconventional physical processes in order to achieve the necessary power-compression in the amplifying medium. The understanding of these new physical mechanisms is developing rapidly. Importantly, although the x-ray source does not currently exist, the understanding of these new physical mechanisms is developing rapidly and the research has established the basic scaling laws that will determine the properties of the x-ray illuminator. When this x-ray source becomes available, an extremely rapid and cost effective instrument for 3-D imaging of biological materials can be applied to a wide range of biological structural assays, including the base-pair sequencing of the human genome and many questions regarding its higher levels of organization.

Rhodes, C.K.

1993-06-08T23:59:59.000Z

Note: This page contains sample records for the topic "x-ray free-electron laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

X-ray shearing interferometer  

DOE Patents [OSTI]

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.

Koch, Jeffrey A. (Livermore, CA)

2003-07-08T23:59:59.000Z

322

Quantitative x-ray imager (abstract)  

SciTech Connect (OSTI)

We report on development of a quantitative x-ray imager (QXI) for the national Inertial Confinement Fusion Program. Included in this development is a study of photocathode response as a function of photon energy, 2--17.5 keV, which is related to diagnostic development on the National Ignition Facility (NIF). The QXI is defined as being a quantative imager due to the repeated characterization. This instrument is systematically checked out, electronically as well as its photocathode x-ray response, both on a direct current and pulsed x-ray sources, before and after its use on a shot campaign. The QXI is a gated x-ray imager1 used for a variety of experiments conducted in the Inertial Confinement Fusion and Radiation Physics Program. The camera was assembled in Los Alamos and has been under development since 1997 and has now become the workhorse framing camera by the program. The electronics were built by Grant Applied Physics of San Fransisco, CA.2 The QXI has been used at the LANL Trident, LLNL Nova, and University of Rochester Laboratory OMEGA laser facilities. The camera consists of a grated microchannel plate (MCP), a phosphor coated fiberoptic faceplate coupled to film for data readout, along with high speed electronic pulsers to drive the x-ray detector. The QXI has both a two-strip and a four-strip detection head and has the ability to individually bias the gain of each of the strips. The timing of the QXI was done at the Trident short pulse laboratory, using 211 nm light. Single strip jitter was looked at as well and determined to be <25 ps. Flatfielding of the photocathode across the MCP was done with the Trident main laser with 150 J on a gold disk with a 1 ns. Spatial resolution was determined to be <5 {mu}m by using the same laser conditions as before and a backlit 1000 lp/in. grid. The QXI has been used on cylindrical implosion work at the Nova Laser Facility, and on direct-drive cylinder mix and indirect-drive high convergence implosion experiments at OMEGA. Its two-strip module has provided the capability to look at point backlighters, as part of technique development for experiments on the NIF. Its next use will be in March 2000 with its off axis viewer nose at Omega, providing a perpendicular view of Rayleigh--Taylor spike dissipation.

Evans, Scott C.; Archuleta, Tom N.; Oertel, John A.; Walsh, Peter J.

2001-01-01T23:59:59.000Z

323

A compact scanning soft X-ray microscope  

SciTech Connect (OSTI)

Soft x-ray microscopes operating at wavelengths between 2.3 nm and 4.4 nm are capable of imaging wet biological cells with a resolution many times that of a visible light microscope. Several such soft x-ray microscopes have been constructed. However, with the exception of contact microscopes, all use synchrotrons as the source of soft x-ray radiation and Fresnel zone plates as the focusing optics. These synchrotron based microscopes are very successful but have the disadvantage of limited access. This dissertation reviews the construction and performance of a compact scanning soft x-ray microscope whose size and accessibility is comparable to that of an electron microscope. The microscope uses a high-brightness laser-produced plasma as the soft x-ray source and normal incidence multilayer-coated mirrors in a Schwarzschild configuration as the focusing optics. The microscope operates at a wavelength of 14 nm, has a spatial resolution of 0.5 {mu}m, and has a soft x-ray photon flux through the focus of 10{sup 4}-10{sup 5} s{sup {minus}1} when operated with only 170 mW of average laser power. The complete system, including the laser, fits on a single 4{prime} x 8{prime} optical table. The significant components of the compact microscope are the laser-produced plasma (LPP) source, the multilayer coatings, and the Schwarzschild objective. These components are reviewed, both with regard to their particular use in the current microscope and with regard to extending the microscope performance to higher resolution, higher speed, and operation at shorter wavelengths. Measurements of soft x-ray emission and debris emission from our present LPP source are presented and considerations given for an optimal LPP source. The LPP source was also used as a broadband soft x-ray source for measurement of normal incidence multilayer mirror reflectance in the 10-25 nm spectral region.

Trail, J.A.

1989-01-01T23:59:59.000Z

324

Dilation x-ray imager a new/faster gated x-ray imager for the NIF  

SciTech Connect (OSTI)

As the yield on implosion shots increases it is expected that the peak x-ray emission reduces to a duration with a FWHM as short as 20 ps for {approx}7 Multiplication-Sign 10{sup 18} neutron yield. However, the temporal resolution of currently used gated x-ray imagers on the NIF is 40-100 ps. We discuss the benefits of the higher temporal resolution for the NIF and present performance measurements for dilation x-ray imager, which utilizes pulse-dilation technology [T. J. Hilsabeck et al., Rev. Sci. Instrum. 81, 10E317 (2010)] to achieve x-ray imaging with temporal gate times below 10 ps. The measurements were conducted using the COMET laser, which is part of the Jupiter Laser Facility at the Lawrence Livermore National Laboratory.

Nagel, S. R.; Bell, P. M.; Bradley, D. K.; Ayers, M. J.; Barrios, M. A.; Felker, B.; Smith, R. F.; Collins, G. W.; Jones, O. S.; Piston, K.; Raman, K. S. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550 (United States); Hilsabeck, T. J.; Kilkenny, J. D.; Chung, T.; Sammuli, B. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States); Hares, J. D.; Dymoke-Bradshaw, A. K. L. [Kentech Instruments Ltd., Wallingford, Oxfordshire OX10 (United Kingdom)

2012-10-15T23:59:59.000Z

325

Femtosecond diffractive imaging with a soft-X-ray free-electron...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Synchrotron Radiation Laboratory, Uppsala University, the Deutsches Elektronen-Synchroton (DESY), and Technische Universitt Berlin. The FLASH FEL began operations at DESY...

326

Science Driven Requirements for Seeded Soft X-ray Free Electron...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Wednesday, October 1, 2014 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Speaker: Fulvio Parmigiani (Elettra Sincrotrone Trieste) Program Description Starting from the...

327

SMB, X-Ray Spectroscopy & Imaging  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Home X-Ray Spectroscopy & Imaging X-Ray Spectroscopy & Imaging SSRL has five hard X-ray Spectroscopy beamlines and three Microfocus Imaging beamlines dedicated to Biological and...

328

X-ray Imaging Workshop  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Imaging and Spectro-microscopy: Imaging and Spectro-microscopy: the Present and the Future Stanford Synchrotron Radiation Laboratory October 8-9, 2002 Organizers: John Miao & Keith Hodgson A workshop on "X-ray Imaging and Spectro-microscopy: the Present and the Future" was held on October 8-9, 2002. This workshop, organized by John Miao (SSRL) and Keith Hodgson (SSRL) provided a forum to discuss the scientific applications of a variety of imaging and spectro-microscopic techniques, including photoemission electron microscopy (PEEM), angle resolved photoemission spectroscopy (ARPES), coherent diffraction imaging, x-ray microscopy, micro-tomography, holographic imaging, and x-ray micro-probe. Twelve invited speakers discussed the important scientific applications of these techniques, and also predicted the future scientific directions with the advance of instrumentation and x-ray sources. The workshop was well attended with over fifty registered attendees.

329

Miniature x-ray source  

DOE Patents [OSTI]

A miniature x-ray source utilizing a hot filament cathode. The source has a millimeter scale size and is capable of producing broad spectrum x-ray emission over a wide range of x-ray energies. The miniature source consists of a compact vacuum tube assembly containing the hot filament cathode, an anode, a high voltage feedthru for delivering high voltage to the cathode, a getter for maintaining high vacuum, a connector for 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 fabricated from highly x-ray transparent materials, such as sapphire, diamond, or boron nitride.

Trebes, James E. (Livermore, CA); Bell, Perry M. (Tracy, CA); Robinson, Ronald B. (Modesto, CA)

2000-01-01T23:59:59.000Z

330

Center for X-Ray Optics, 1992  

SciTech Connect (OSTI)

This report discusses the following topics: Center for X-Ray Optics; Soft X-Ray Imaging wit Zone Plate Lenses; Biological X-Ray microscopy; Extreme Ultraviolet Lithography for Nanoelectronic Pattern Transfer; Multilayer Reflective Optics; EUV/Soft X-ray Reflectometer; Photoemission Microscopy with Reflective Optics; Spectroscopy with Soft X-Rays; Hard X-Ray Microprobe; Coronary Angiography; and Atomic Scattering Factors.

Not Available

1993-08-01T23:59:59.000Z

331

X-ray Stacking 2008-Apr-22 Astrostats X-ray Stacking  

E-Print Network [OSTI]

X-ray Stacking 2008-Apr-22 Astrostats X-ray Stacking Tom Aldcroft SAO/CXC #12;X-ray Stacking 2008 analysis for a sample Stacking ­ mean properties of sample Chandra X-ray data (faint point sources) are photon-limited with low background => stacking in X-rays is very effective #12;X-ray Stacking 2008-Apr-22

Wolfe, Patrick J.

332

Center for X-Ray Optics, 1991  

SciTech Connect (OSTI)

This report discusses: Soft-X-Ray imaging with zone-plate lenses; multilayer reflective optics; and spectroscopy with x-rays.

Not Available

1992-03-01T23:59:59.000Z

333

SMB, X-ray Absorption Spectroscopy  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Absorption Spectroscopy X-ray Absorption Spectroscopy X-ray absorption spectroscopy (XAS) is a well-established technique for simultaneous local geometric and electronic structure...

334

Tokamak x ray diagnostic instrumentation  

SciTech Connect (OSTI)

Three classes of x-ray diagnostic instruments enable measurement of a variety of tokamak physics parameters from different features of the x-ray emission spectrum. (1) The soft x-ray (1 to 50 keV) pulse-height-analysis (PHA) diagnostic measures impurity concentrations from characteristic line intensities and the continuum enhancement, and measures the electron temperature from the continuum slope. (2) The Bragg x-ray crystal spectrometer (XCS) measures the ion temperature and neutral-beam-induced toroidal rotation velocity from the Doppler broadening and wavelength shift, respectively, of spectral lines of medium-Z impurity ions. Impurity charge state distributions, precise wavelengths, and inner-shell excitation and recombination rates can also be studied. X rays are diffracted and focused by a bent crystal onto a position-sensitive detector. The spectral resolving power E/..delta..E is greater than 10/sup 4/ and time resolution is 10 ms. (3) The x-ray imaging system (XIS) measures the spatial structure of rapid fluctuations (0.1 to 100 kHZ) providing information on MHD phenomena, impurity transport rates, toroidal rotation velocity, plasma position, and the electron temperature profile. It uses an array of silicon surface-barrier diodes which view different chords of the plasma through a common slot aperture and operate in current (as opposed to counting) mode. The effectiveness of shields to protect detectors from fusion-neutron radiation effects has been studied both theoretically and experimentally.

Hill, K.W.; Beiersdorfer, P.; Bitter, M.; Fredrickson, E.; Von Goeler, S.; Hsuan, H.; Johnson, L.C.; Liew, S.L.; McGuire, K.; Pare, V.

1987-01-01T23:59:59.000Z

335

Axial interaction free-electron laser  

DOE Patents [OSTI]

Electron orbits from a helical axial wiggler in an axial guide field are absolutely unstable as power is extracted from the particles. For off-axis beams an axial FEL mechanism exists when the axial electric field in a TM mode is wiggled to interact with the axial velocity of the electrons that form the beam. The interaction strength is comparable to that for helical FELs and is insensitive to beam orbit errors. The orbits for this mechanism are extremely stable in the absence of space charge and lead to high extraction efficiencies without particle phasing incoherence or interception. This interaction mechanism is suitable for use with intense annular electron beams for high power generation at microwave frequencies. 5 figs.

Carlsten, B.E.

1997-09-02T23:59:59.000Z

336

Free-Electron Lasers: Status and Applications  

Science Journals Connector (OSTI)

...average power record for an FEL was 11 W (35). An experiment at Boeing (36) demonstrated the ability...power record for an FEL was 11-W (35). An experiment at Boeing (36) demonstrated the ability of photoinjectors to produce...

Patrick G. O'Shea; Henry P. Freund

2001-06-08T23:59:59.000Z

337

National Ignition Facility core x-ray streak camera  

SciTech Connect (OSTI)

The National Ignition Facility (NIF) core x-ray streak camera will be used for laser performance verification experiments as well as a wide range of physics experiments in the areas of high-energy-density science, inertial confinement fusion, and basic science. The x-ray streak camera system is being designed to record time-dependent x-ray emission from NIF targets using an interchangeable family of snouts for measurements such as one-dimensional (1D) spatial imaging or spectroscopy. the NIF core x-ray streak camera will consist of an x-ray-sensitive photocathode that detects x rays with 1D spatial resolution coupled to an electron streak tube to detect a continuous time history of the x rays incident on the photocathode over selected time periods. A charge-coupled-device (CCD) readout will record the signal from the streak tube. The streak tube, CCD, and associated electronics will reside in an electromagnetic interference, and electromagnetic pulse protected, hermetically sealed, temperature-controlled box whose internal pressure is approximately 1 atm. The streak tube itself will penetrate through the wall of the box into the target chamber vacuum. We are working with a goal of a spatial resolution of 15 lp/mm with 50% contrast transfer function at the photocathode and adjustment sweep intervals of 1--50 ns. The camera spectral sensitivity extends from soft x rays to 20 keV x rays, with varying quantum efficiency based on photocathode selection. The system will have remote control, monitoring, and Ethernet communications through an embedded controller. The core streak camera will be compatible with the instrument manipulators at the OMEGA (University of Rochester) and NIF facilities.

Kimbrough, J. R.; Bell, P. M.; Christianson, G. B.; Lee, F. D.; Kalantar, D. H.; Perry, T. S.; Sewall, N. R.; Wootton, A. J.

2001-01-01T23:59:59.000Z

338

Theoretical treatments of the bound-free contribution and experimental best practice in X-ray Thomson scattering from warm dense matter  

SciTech Connect (OSTI)

By comparison with high-resolution synchrotron x-ray experimental results, we assess several theoretical treatments for the bound-free (core-electron) contribution to x-ray Thomson scattering (i.e., also known as nonresonant inelastic x-ray scattering). We identify an often overlooked source of systematic error in the plane-wave form factor approximation (PWFFA) used in the inference of temperature, ionization state, and free electron density in some laser-driven compression studies of warm dense matter. This error is due to a direct violation of energy conservation in the PWFFA. We propose an improved practice for the bound-free term that will be particularly relevant for XRTS experiments performed with somewhat improved energy resolution at the National Ignition Facility or the Linac Coherent Light Source. Our results raise important questions about the accuracy of state variable determination in XRTS studies, given that the limited information content in low-resolution XRTS spectra does not strongly constrain the models of electronic structure being used to fit the spectra.

Mattern, Brian A.; Seidler, Gerald T. [Department of Physics, University of Washington, Seattle, Washington 98195-1560 (United States)

2013-02-15T23:59:59.000Z

339

X-ray Emission from Massive Stars  

E-Print Network [OSTI]

X-ray Emission from Massive Stars David Cohen Department of Physics and Astronomy Swarthmore be related to the production of X-rays on massive stars. If so, massive stars' X-rays are much different than those found our own Sun and other cooler stars like the Sun that produce X-rays via magnetic activity

Cohen, David

340

X-ray Emission from Massive Stars  

E-Print Network [OSTI]

X-ray Emission from Massive Stars David Cohen Department of Physics and Astronomy Swarthmore #12;What is the mechanism by which massive stars produce x-rays? New results from the Chandra X-ray Observatory ­ high-resolution x-ray spectroscopy: measuring Doppler broadening in emission lines Testing

Cohen, David

Note: This page contains sample records for the topic "x-ray free-electron laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

7 Å Resolution in Protein 2-Dimentional-Crystal X-Ray Diffraction at Linac Coherent Light Source  

SciTech Connect (OSTI)

Membrane proteins arranged as two-dimensional (2D) crystals in the lipid en- vironment provide close-to-physiological structural information, which is essential for understanding the molecular mechanisms of protein function. X-ray diffraction from individual 2D crystals did not represent a suitable investigation tool because of radiation damage. The recent availability of ultrashort pulses from X-ray Free Electron Lasers (X-FELs) has now provided a mean to outrun the damage. Here we report on measurements performed at the LCLS X-FEL on bacteriorhodopsin 2D crystals mounted on a solid support and kept at room temperature. By merg- ing data from about a dozen of single crystal diffraction images, we unambiguously identified the diffraction peaks to a resolution of 7 °A, thus improving the observable resolution with respect to that achievable from a single pattern alone. This indicates that a larger dataset will allow for reliable quantification of peak intensities, and in turn a corresponding increase of resolution. The presented results pave the way to further X-FEL studies on 2D crystals, which may include pump-probe experiments at subpicosecond time resolution.

Pedrini, Bill; Tsai, Ching-Ju; Capitani, Guido; Padeste, Celestino; Hunter, Mark; Zatsepin, Nadia A.; Barty, Anton; Benner, Henry; Boutet, Sebastien; Feld, Geoffrey K.; Hau-Riege, Stefan; Kirian, Rick; Kupitz, Christopher; Messerschmidt, Marc; Ogren, John I.; Pardini, Tommaso; Segelke, Brent; Williams, Garth J.; Spence , John C.; Abela, Rafael; Coleman, Matthew A.; Evans, James E.; Schertler, Gebhard; Frank, Matthias; Li, Xiao-Dan

2014-06-09T23:59:59.000Z

342

Signal averaging x-ray streak camera with picosecond jitter A. Maksimchuk, M. Kim, J. Workman, G. Korn,a)  

E-Print Network [OSTI]

pulse laser-produced plasma. Accumulation of the streaked x-ray signals significantly improvedSignal averaging x-ray streak camera with picosecond jitter A. Maksimchuk, M. Kim, J. Workman, G picosecond x-ray streak camera using a dc-biased photoconductive switch as a generator of a high-voltage ramp

Umstadter, Donald

343

X-ray diffraction experiments with femtosecond time D. VON DER LINDE and K. SOKOLOWSKI-TINTEN  

E-Print Network [OSTI]

X-ray diffraction experiments with femtosecond time resolution D. VON DER LINDE and K. SOKOLOWSKI-essen.de (Received 4 March 2002) Abstract. Intense ultrashort laser pulses enable the generation of subpico- second X-ray pulses in the multi-kilovolt range of photon energies. These X- ray pulses have opened the door

von der Linde, D.

344

Compact x-ray source and panel  

DOE Patents [OSTI]

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.

Sampayon, Stephen E. (Manteca, CA)

2008-02-12T23:59:59.000Z

345

Using Light to Control How X Rays Interact with Matter  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Using Light to Control How X Using Light to Control How X Rays Interact with Matter Using Light to Control How X Rays Interact with Matter Print Wednesday, 27 January 2010 00:00 Schemes that use one light pulse to manipulate interactions of another with matter are well developed in the visible-light regime where an optical control pulse influences how an optical probe pulse interacts with a medium. This approach has opened new research directions in fields like quantum computing and nonlinear optics, while also spawning entirely new research areas, such as electromagnetically induced transparency and slow light. However, it has been unclear whether similar optical control schemes could be used to modify how x rays interact with matter. In a dramatic breakthrough demonstration at the ALS, a Berkeley Lab-Argonne National Laboratory group has now used powerful visible-light lasers to render a nominally opaque material transparent to x rays. While x-ray transparency will have immediate applications at x-ray light sources, the important result is that the findings lay a foundation for a broader spectrum of applications.

346

Using Light to Control How X Rays Interact with Matter  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Using Light to Control How X Rays Interact with Matter Print Using Light to Control How X Rays Interact with Matter Print Schemes that use one light pulse to manipulate interactions of another with matter are well developed in the visible-light regime where an optical control pulse influences how an optical probe pulse interacts with a medium. This approach has opened new research directions in fields like quantum computing and nonlinear optics, while also spawning entirely new research areas, such as electromagnetically induced transparency and slow light. However, it has been unclear whether similar optical control schemes could be used to modify how x rays interact with matter. In a dramatic breakthrough demonstration at the ALS, a Berkeley Lab-Argonne National Laboratory group has now used powerful visible-light lasers to render a nominally opaque material transparent to x rays. While x-ray transparency will have immediate applications at x-ray light sources, the important result is that the findings lay a foundation for a broader spectrum of applications.

347

Using Light to Control How X Rays Interact with Matter  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Using Light to Control How X Rays Interact with Matter Print Using Light to Control How X Rays Interact with Matter Print Schemes that use one light pulse to manipulate interactions of another with matter are well developed in the visible-light regime where an optical control pulse influences how an optical probe pulse interacts with a medium. This approach has opened new research directions in fields like quantum computing and nonlinear optics, while also spawning entirely new research areas, such as electromagnetically induced transparency and slow light. However, it has been unclear whether similar optical control schemes could be used to modify how x rays interact with matter. In a dramatic breakthrough demonstration at the ALS, a Berkeley Lab-Argonne National Laboratory group has now used powerful visible-light lasers to render a nominally opaque material transparent to x rays. While x-ray transparency will have immediate applications at x-ray light sources, the important result is that the findings lay a foundation for a broader spectrum of applications.

348

Coherent X-ray Imaging Data Bank (CXIDB): An Open Repository for CXI Experimental Data  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

Nowadays there are several groups around the world doing excellent work using different kinds of techniques all based on the physics of coherent X-ray imaging (CXI). Due to several reasons, including lack of a standard file format, there has been limited sharing of data which severely limits possible synergies inside the community. At the same time there is a population of researchers who do not have access to the facilities required to make such kinds of experiments, or do not have the expertise and resources necessary to carry them out. But many of them would be able to test new ideas and techniques if they would have access to the experimental data. The main goal of the Coherent X-ray Imaging Data Bank is to address these problems by creating an open repository for CXI experimental data. Such a repository provides several important benefits including: Expansion of the CXI community directly leading to an increase in the science output, the existence of an archival place for all the experimental data would ensure that such data does not gets lost forever when the group that did the experiment is no longer interested in the data, the availability of the experimental data to the entire community greatly facilitates reproducibility, leading to higher quality and more transparent science, the development of a well documented file format for CXI data facilitates data sharing and might one day lead to its emergence as a de facto standard. Current free electron laser facilities such as the LCLS are capable of producing very large amounts of data (20TB a day) and the coming European FEL is expected to increase this rate a factor of 500. The analyzes of such large bodies of data will have to be distributed through a large community to make it manageable, and this repository could be an important facilitator in this process.

349

Focused X-ray source  

DOE Patents [OSTI]

Disclosed is an intense, relatively inexpensive X-ray source (as compared to a synchrotron emitter) for technological, scientific, and spectroscopic purposes. A conical radiation pattern produced by a single foil or stack of foils is focused by optics to increase the intensity of the radiation at a distance from the conical radiator. 8 figs.

Piestrup, M.A.; Boyers, D.G.; Pincus, C.I.; Maccagno, P.

1990-08-21T23:59:59.000Z

350

Automatic detection of bone fragments in poultry using multi-energy x-rays  

DOE Patents [OSTI]

At least two linear arrays of x-ray detectors are placed below a conveyor belt in a poultry processing plant. Multiple-energy x-ray sources illuminate the poultry and are detected by the detectors. Laser profilometry is used to measure the poultry thickness as the x-ray data is acquired. The detector readout is processed in real time to detect the presence of small highly attenuating fragments in the poultry, i.e., bone, metal, and cartilage.

Gleason, Shaun S. (Knoxville, TN); Paulus, Michael J. (Knoxville, TN); Mullens, James A. (Knoxville, TN)

2002-04-09T23:59:59.000Z

351

X-Ray Diffraction on NIF  

SciTech Connect (OSTI)

The National Ignition Facility (NIF) is currently a 192 beam, 1.6 MJ laser. NIF Ramp-Compression Experiments have already made the relevant exo-planet pressure range from 1 to 50 Mbar accessible. We Proposed to Study Carbon Phases by X-Ray Diffraction on NIF. Just a few years ago, ultra-high pressure phase diagrams for materials were very 'simple'. New experiments and theories point out surprising and decidedly complex behavior at the highest pressures considered. High pressures phases of aluminum are also predicted to be complex. Recent metadynamics survey of carbon proposed a dynamic pathway among multiple phases. We need to develop diagnostics and techniques to explore this new regime of highly compressed matter science. X-Ray Diffraction - Understand the phase diagram/EOS/strength/texture of materials to 10's of Mbar. Strategy and physics goals: (1) Powder diffraction; (2) Begin with diamond; (3) Continue with metals etc.; (4) Explore phase diagrams; (5) Develop liquid diffraction; and (6) Reduce background/improve resolution.

Eggert, J H; Wark, J

2012-02-15T23:59:59.000Z

352

Microgap x-ray detector  

DOE Patents [OSTI]

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.

Wuest, Craig R. (Danville, CA); Bionta, Richard M. (Livermore, CA); Ables, Elden (Livermore, CA)

1994-01-01T23:59:59.000Z

353

Chest x-Rays | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Chest x-Rays Chest x-Rays Chest x-Rays Chest X-ray B-Reading The B-reading is a special reading of a standard chest x-ray film performed by a physician certified by the National Institute for Occupational Safety and Health (NIOSH). The reading looks for changes on the chest x-ray that may indicate exposure and disease caused by agents such as asbestos or silica. The B-reading is considered a special reading because doctors who are certified by NIOSH to perform B-readings use a specific protocol to read and record the findings as developed by the International Labour Organization (ILO). The ILO's protocol provides rules for systematically examining the x-ray in a step-by-step method and recording certain abnormalities or changes on the chest x-ray that can be attributable to

354

Producing X-rays at the APS  

ScienceCinema (OSTI)

An introduction and overview of the Advanced Photon Source at Argonne National Laboratory, the technology that produces the brightest X-ray beams in the Western Hemisphere, and the research carried out by scientists using those X-rays.

None

2013-04-19T23:59:59.000Z

355

SMB, X-ray Fluorescence Imaging  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Fluorescence Imaging X-ray Fluorescence Imaging X-ray fluorescence imaging utilizes the high brightness of SPEAR3 and focused beam generated by the uses of K-B optics, capillaries...

356

Monochromatic x-ray sampling streak imager for fast-ignitor plasma observation  

SciTech Connect (OSTI)

Ultrafast two-dimensional (2D) x-ray imaging is required to investigate the dynamics of fast-heated core plasma in inertial confinement fusion research. A novel x-ray imager, consisting of two toroidally bent Bragg crystals and an ultrafast 2D x-ray imaging camera, has been demonstrated. Sequential and 2D monochromatic x-ray images of laser-imploded core plasma were obtained with a temporal resolution of 20 ps, a spatial resolution of 31 {mu}m, and a spectral resolution of over 200, simultaneously.

Tanabe, Minoru; Fujiwara, Takashi; Fujioka, Shinsuke; Nishimura, Hiroaki; Shiraga, Hiroyuki; Azechi, Hiroshi; Mima, Kunioki [Institute of Laser Engineering, Osaka University, 2-6 Yamada-Oka, Suita, Osaka 565-0871 (Japan)

2008-10-15T23:59:59.000Z

357

Ultrafast x-ray diffraction for measurements of structural dynamics in shocked metals  

SciTech Connect (OSTI)

An experiment on structural dynamics at the ultrafast time scale in shocked metal samples is presented. The technique development of an ultrafast x-ray diffractometer to generate 'molecular movies' is described. Preliminary results of static x-ray measurements of thin unshocked Ga samples are presented. Initial experiments use 200-300 mJ of a 100fs Ti:Sapphire laser to excite K-alpha x-ray emission in an aluminum wire. The x-ray emission is relayed using a spherical crystal to the sample target. Plans for experiments using Cu K-alpha emission will also be described.

Workman, J. B. (Jonathan B.); Keiter, P. A. (Paul A.); Kyrala, George A.; Roberts, J. P. (Jeffrey); Taylor, Antoinette J.,; Funk, D. J. (David J.)

2002-01-01T23:59:59.000Z

358

Chandra X-ray Observatory Center  

E-Print Network [OSTI]

Chandra X-ray Observatory Center Harvard-Smithsonian Center for Astrophysics 60 Garden St in hot gas about 250 million light years from Earth. (Credit: X-ray: NASA/CXC/SAO/E.Bulbul, et al-Newton has revealed a mysterious X-ray signal in the data. This signal is represented in the circled data

359

X-Ray Absorption Spectroscopy of Metallobiomolecules  

E-Print Network [OSTI]

2/9/07 1 X-Ray Absorption Spectroscopy of Metallobiomolecules The Outskirts of Structural Biology 9, 07] This is a tutorial about the use of X-ray Absorption Spectroscopy (XAS) in biology, RG; Eisenberger, P; Kincaid, BM "X-ray Absorption Spectroscopy of Biological Molecules" Annu. Rev

Scott, Robert A.

360

Chandra X-ray Observatory Center  

E-Print Network [OSTI]

Chandra X-ray Observatory Center Harvard-Smithsonian Center for Astrophysics 60 Garden St million light years from Earth. (Credit: X-ray: NASA/CXC/Wesleyan Univ./R.Kilgard, et al; Optical: NASA with optical data from the Hubble Space Telescope (red, green, and blue). The X-ray data reveal hundreds

Note: This page contains sample records for the topic "x-ray free-electron laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

X-ray Spectroscopy of Cool Stars  

E-Print Network [OSTI]

High-resolution X-ray spectroscopy has addressed not only various topics in coronal physics of stars, but has also uncovered important features relevant for our understanding of stellar evolution and the stellar environment. I summarize recent progress in coronal X-ray spectroscopy and in particular also discuss new results from studies of X-rays from pre-main sequence stars.

M. Guedel

2006-09-11T23:59:59.000Z

362

X-Ray Physics Evan Berkowitz  

E-Print Network [OSTI]

X-Ray Physics Evan Berkowitz Junior, MIT Department of Physics (Dated: October 25, 2006) We measure a variety of phenomena related to X-Ray absorption and production. We present data which conforms within, as are 22 Na electron-positron annhilation lines. The importance of understanding x-rays is demonstrated

363

Chandra X-ray Observatory Center  

E-Print Network [OSTI]

Chandra X-ray Observatory Center Harvard-Smithsonian Center for Astrophysics 60 Garden St 200 million light years from Earth. (Credit: X-ray: NASA/CXC/UAH/M.Sun et al; Optical: NASA, ESA, & the Hubble Heritage Team (STScI/AURA) Caption: This composite image from the Chandra X-ray Observatory (blue

364

X-Ray Absorption Spectroscopy of Metallobiomolecules  

E-Print Network [OSTI]

9/6/09 1 X-Ray Absorption Spectroscopy of Metallobiomolecules The Outskirts of Structural Biology 6, 09] This is a tutorial about the use of X-ray Absorption Spectroscopy (XAS) in biology, RG; Eisenberger, P; Kincaid, BM "X-ray Absorption Spectroscopy of Biological Molecules" Annu. Rev

Scott, Robert A.

365

Chandra X-ray Observatory Center  

E-Print Network [OSTI]

Chandra X-ray Observatory Center Harvard-Smithsonian Center for Astrophysics 60 Garden St. Cambridge, MA 02138 USA http://chandra.harvard.edu Four Supernova Remnants: NASA's Chandra X-ray Observatory's Chandra X-ray Observatory, four newly processed images of supernova remnants dramatically illustrate

366

Lessening X-ray damage is healthy for protein discovery data too | Argonne  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

The brightness and energy of X-ray beams are critical properties for The brightness and energy of X-ray beams are critical properties for research. The APS Upgrade will make our X-ray beams brighter, meaning more X-rays can be focused onto a smaller, laser-like spot, allowing researchers to gather more data in greater detail in less time. Lessening X-ray damage is healthy for protein discovery data too December 16, 2013 Tweet EmailPrint New recommendations for using X-rays promise to speed investigations aimed at understanding the structure and function of biologically important proteins - information critical to the development of new drugs. Scientists from two U.S. Department of Energy national laboratories, Argonne and Brookhaven, and the University of Washington, Seattle, evaluated options to remedy problems affecting data collection in their new

367

January 15, 1992 / Vol. 17, No. 2 / OPTICS LETTERS First stage in the development of a soft-x-ray reflection  

E-Print Network [OSTI]

rough- ness). The Schwarzschild objective is made of a large concave mirror and a small convex mirror-x-ray reflection imaging microscope in the Schwarzschild configuration using a soft-x-ray laser at 18.2nm D. S. Di in the Schwarzschild configuration. A soft-x-ray laser operating at 18.2nm was used as the x-ray source. Mo

Kim, Jae-Hoon

368

X-RAY SPECTROMETRY X-Ray Spectrom. 2007; 36: 336342  

E-Print Network [OSTI]

X-RAY SPECTROMETRY X-Ray Spectrom. 2007; 36: 336­342 Published online in Wiley InterScience (www.interscience.wiley.com) DOI: 10.1002/xrs.980 Fish otolith trace element maps: new approaches with synchrotron microbeam x-ray of elements as they accrete through a fish's life. We apply synchrotron microbeam x-ray fluorescence methods

Limburg, Karin E.

369

X-ray Pulsations in the Supersoft X-ray Binary CAL 83  

E-Print Network [OSTI]

X-ray data reveal that the supersoft X-ray binary CAL 83 exhibits 38.4 minute pulsations at some epochs. These X-ray variations are similar to those found in some novae and are likely to be caused by nonradial pulsations the white dwarf. This is the first detection of pulsations in a classical supersoft X-ray binary.

P. C. Schmidtke; A. P. Cowley

2005-09-28T23:59:59.000Z

370

X-ray Spectroscopy of Cooling Cluster  

SciTech Connect (OSTI)

We review the X-ray spectra of the cores of clusters of galaxies. Recent high resolution X-ray spectroscopic observations have demonstrated a severe deficit of emission at the lowest X-ray temperatures as compared to that expected from simple radiative cooling models. The same observations have provided compelling evidence that the gas in the cores is cooling below half the maximum temperature. We review these results, discuss physical models of cooling clusters, and describe the X-ray instrumentation and analysis techniques used to make these observations. We discuss several viable mechanisms designed to cancel or distort the expected process of X-ray cluster cooling.

Peterson, J.R.; /SLAC; Fabian, A.C.; /Cambridge U., Inst. of Astron.

2006-01-17T23:59:59.000Z

371

X-ray transmissive debris shield  

DOE Patents [OSTI]

An X-ray debris shield for use in X-ray lithography that is comprised of an X-ray window having a layer of low density foam exhibits increased longevity without a substantial increase in exposure time. The low density foam layer serves to absorb the debris emitted from the X-ray source and attenuate the shock to the window so as to reduce the chance of breakage. Because the foam is low density, the X-rays are hardly attenuated by the foam and thus the exposure time is not substantially increased.

Spielman, R.B.

1996-05-21T23:59:59.000Z

372

X-ray Spectroscopy of Cooling Clusters  

E-Print Network [OSTI]

We review the X-ray spectra of the cores of clusters of galaxies. Recent high resolution X-ray spectroscopic observations have demonstrated a severe deficit of emission at the lowest X-ray temperatures as compared to that expected from simple radiative cooling models. The same observations have provided compelling evidence that the gas in the cores is cooling below half the maximum temperature. We review these results, discuss physical models of cooling clusters, and describe the X-ray instrumentation and analysis techniques used to make these observations. We discuss several viable mechanisms designed to cancel or distort the expected process of X-ray cluster cooling.

J. R. Peterson; A. C. Fabian

2005-12-21T23:59:59.000Z

373

X-ray transmissive debris shield  

DOE Patents [OSTI]

An X-ray debris shield for use in X-ray lithography that is comprised of an X-ray window having a layer of low density foam exhibits increased longevity without a substantial increase in exposure time. The low density foam layer serves to absorb the debris emitted from the X-ray source and attenuate the shock to the window so as to reduce the chance of breakage. Because the foam is low density, the X-rays are hardly attenuated by the foam and thus the exposure time is not substantially increased.

Spielman, Rick B. (Albuquerque, NM)

1996-01-01T23:59:59.000Z

374

X-ray lithography using holographic images  

DOE Patents [OSTI]

A non-contact X-ray projection lithography method for producing a desired X-ray image on a selected surface of an X-ray-sensitive material, such as photoresist material on a wafer, the desired X-ray image having image minimum linewidths as small as 0.063 .mu.m, or even smaller. A hologram and its position are determined that will produce the desired image on the selected surface when the hologram is irradiated with X-rays from a suitably monochromatic X-ray source of a selected wavelength .lambda.. On-axis X-ray transmission through, or off-axis X-ray reflection from, a hologram may be used here, with very different requirements for monochromaticity, flux and brightness of the X-ray source. For reasonable penetration of photoresist materials by X-rays produced by the X-ray source, the wavelength X, is preferably chosen to be no more than 13.5 nm in one embodiment and more preferably is chosen in the range 1-5 nm in the other embodiment. A lower limit on linewidth is set by the linewidth of available microstructure writing devices, such as an electron beam.

Howells, Malcolm R. (Berkeley, CA); Jacobsen, Chris (Sound Beach, NY)

1995-01-01T23:59:59.000Z

375

Optical synchronization system for femtosecond X-ray sources  

DOE Patents [OSTI]

Femtosecond pump/probe experiments using short X-Ray and optical pulses require precise synchronization between 100 meter-10 km separated lasers in a various experiments. For stabilization in the hundred femtosecond range a CW laser is amplitude modulated at 1-10 GHz, the signal retroreflected from the far end, and the relative phase used to correct the transit time with various implementations. For the sub-10 fsec range the laser frequency itself is upshifted 55 MHz with an acousto-optical modulator, retroreflected, upshifted again and phase compared at the sending end to a 110 MHz reference. Initial experiments indicate less than 1 fsec timing jitter. To lock lasers in the sub-10 fs range two single-frequency lasers separated by several teraHertz will be lock to a master modelocked fiber laser, transmit the two frequencies over fiber, and lock two comb lines of a slave laser to these frequencies, thus synchronizing the two modelocked laser envelopes.

Wilcox, Russell B. (El Cerrito, CA); Holzwarth, Ronald (Munich, DE)

2011-12-13T23:59:59.000Z

376

X-Ray Emission from a 1 kJ Plasma Focus  

Science Journals Connector (OSTI)

Several devices capable of producing dense, high temperature plasma are presently investigated as possible sources in the soft x-ray range [3.1–6]. Among these are the laser-induced plasma, the gas puff systems, ...

G. Herziger

1984-01-01T23:59:59.000Z

377

Note: Application of a pixel-array area detector to simultaneous single crystal x-ray diffraction and x-ray absorption spectroscopy measurements  

SciTech Connect (OSTI)

X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS) are two main x-ray techniques in synchrotron radiation facilities. In this Note, we present an experimental setup capable of performing simultaneous XRD and XAS measurements by the application of a pixel-array area detector. For XRD, the momentum transfer in specular diffraction was measured by scanning the X-ray energy with fixed incoming and outgoing x-ray angles. By selecting a small fixed region of the detector to collect the XRD signal, the rest of the area was available for collecting the x-ray fluorescence for XAS measurements. The simultaneous measurement of XRD and X-ray absorption near edge structure for Pr{sub 0.67}Sr{sub 0.33}MnO{sub 3} film was demonstrated as a proof of principle for future time-resolved pump-probe measurements. A static sample makes it easy to maintain an accurate overlap of the X-ray spot and laser pump beam.

Sun, Cheng-Jun, E-mail: cjsun@aps.anl.gov; Brewe, Dale L.; Heald, Steve M. [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States)] [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Zhang, Bangmin [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States) [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Department of Materials Science and Engineering, National University of Singapore, 117575 Singapore (Singapore); NUSNNI-Nanocore, National University of Singapore, 117411 Singapore (Singapore); Chen, Jing-Sheng; Chow, G. M. [Department of Materials Science and Engineering, National University of Singapore, 117575 Singapore (Singapore)] [Department of Materials Science and Engineering, National University of Singapore, 117575 Singapore (Singapore); Venkatesan, T. [NUSNNI-Nanocore, National University of Singapore, 117411 Singapore (Singapore) [NUSNNI-Nanocore, National University of Singapore, 117411 Singapore (Singapore); Department of Physics, National University of Singapore, 117542 Singapore (Singapore); Department of Electrical and Computer Engineering, National University of Singapore, 117575 Singapore (Singapore)

2014-04-15T23:59:59.000Z

378

X-ray Observations of Mrk 231  

E-Print Network [OSTI]

This paper presents new X-ray observations of Mrk 231, an active galaxy of particular interest due to its large infrared luminosity and the presence of several blueshifted broad absorption line (BAL) systems, a phenomenon observed in a small fraction of QSOs. A ROSAT HRI image of Mrk 231 is presented, this shows an extended region of soft X-ray emission, covering several tens of kpc, consistent with the extent of the host galaxy. An ASCA observation of Mrk 231 is also presented. Hard X-rays are detected but the data show no significant variability in X-ray flux. The hard X-ray continuum is heavily attenuated and X-ray column estimates range from ~ 2 x 10^{22} - 10^{23} cm^{-2} depending on whether the material is assumed to be neutral or ionized, and on the model assumed for the extended X-ray component. These ASCA data provide only the second hard X-ray spectrum of a BAL AGN presented to date. The broad-band spectral-energy-distribution of the source is discussed. While Mrk 231 is X-ray weak compared to Seyfert 1 galaxies, it has an optical-to-X-ray spectrum typical of a QSO.

T. J. Turner

1998-08-10T23:59:59.000Z

379

Hard x-ray imaging from explorer  

SciTech Connect (OSTI)

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

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

1981-11-01T23:59:59.000Z

380

Monochromatic x-ray radiography for areal-density measurement of inertial fusion energy fuel in fast ignition experiment  

SciTech Connect (OSTI)

Ultrafast, two-dimensional x-ray imaging is an important diagnostics for the inertial fusion energy research, especially in investigating implosion dynamics at the final stage of the fuel compression. Although x-ray radiography was applied to observing the implosion dynamics, intense x-rays emitted from the high temperature and dense fuel core itself are often superimposed on the radiograph. This problem can be solved by coupling the x-ray radiography with monochromatic x-ray imaging technique. In the experiment, 2.8 or 5.2 keV backlight x-rays emitted from laser-irradiated polyvinyl chloride or vanadium foils were selectively imaged by spherically bent quartz crystals with discriminating the out-of-band emission from the fuel core. This x-ray radiography system achieved 24 {mu}m and 100 ps of spatial and temporal resolutions, respectively.

Fujioka, Shinsuke; Fujiwara, Takashi; Tanabe, Minoru; Nishimura, Hiroaki; Nagatomo, Hideo; Ohira, Shinji; Shiraga, Hiroyuki; Azechi, Hiroshi [Institute of Laser Engineering, Osaka University, 2-6 Yamada-oka, Suita Osaka, 565-0871 (Japan); Inubushi, Yuichi [Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871 (Japan)

2010-10-15T23:59:59.000Z

Note: This page contains sample records for the topic "x-ray free-electron laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

High speed x-ray beam chopper  

DOE Patents [OSTI]

A fast, economical, and compact x-ray beam chopper with a small mass and a small moment of inertia whose rotation can be synchronized and phase locked to an electronic signal from an x-ray source and be monitored by a light beam is disclosed. X-ray bursts shorter than 2.5 microseconds have been produced with a jitter time of less than 3 ns.

McPherson, Armon (Oswego, IL); Mills, Dennis M. (Naperville, IL)

2002-01-01T23:59:59.000Z

382

Colloid Coalescence with Focused X Rays  

SciTech Connect (OSTI)

We show direct evidence that focused x rays enable us to merge polymer colloidal particles at room temperature. This phenomenon is ascribed to the photochemical scission of colloids with x rays, reducing the molecular weight, glass transition temperature, surface tension, and viscosity of colloids. The observation of the neck bridge growth with time shows that the x-ray-induced colloid coalescence is analogous to viscoelastic coalescence. This finding suggests a feasible protocol of photonic nanofabrication by sintering or welding of polymers, without thermal damage, using x-ray photonics.

Weon, B. M.; Kim, J. T.; Je, J. H. [X-ray Imaging Center, Department of Materials Science and Engineering, Pohang University of Science and Technology, Pohang, 790-784 (Korea, Republic of); Yi, J. M. [Samsung Advanced Institute of Technology, Yongin, Gyeonggi, 446-712 (Korea, Republic of); Wang, S.; Lee, W.-K. [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

2011-07-01T23:59:59.000Z

383

X-RAY MICROBEAM SPEECH PRODUCTION DATABASE  

E-Print Network [OSTI]

X-RAY MICROBEAM SPEECH PRODUCTION DATABASE USER'S HANDBOOK Version 1.0 (June 1994) prepared by John . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Chapter Two: XRMB History

384

Automation in X-Ray Crystallography  

Science Journals Connector (OSTI)

Automation in X-Ray Crystallography ... But in the past few years, automation procedures have been applied to intrinsically superior experimental methods. ...

S.C. ABRAHAMS

1963-06-03T23:59:59.000Z

385

Compound refractive X-ray lens  

DOE Patents [OSTI]

An apparatus and method for focusing X-rays. In one embodiment, his invention is a commercial-grade compound refractive X-ray lens. The commercial-grade compound refractive X-ray lens includes a volume of low-Z material. The volume of low-Z material has a first surface which is adapted to receive X-rays of commercially-applicable power emitted from a commercial-grade X-ray source. The volume of low-Z material also has a second surface from which emerge the X-rays of commercially-applicable power which were received at the first surface. Additionally, the commercial-grade compound refractive X-ray lens includes a plurality of openings which are disposed between the first surface and the second surface. The plurality of openings are oriented such that the X-rays of commercially-applicable power which are received at the first surface, pass through the volume of low-Z material and through the plurality openings. In so doing, the X-rays which emerge from the second surface are refracted to a focal point.

Nygren, David R. (Berkeley, CA); Cahn, Robert (Walnut Creek, CA); Cederstrom, Bjorn (Traellborg, SE); Danielsson, Mats (Stocksund, SE); Vestlund, Jonas (Stockholm, SE)

2000-01-01T23:59:59.000Z

386

X-Ray Science Division (XSD)  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

X-Ray Science Division (XSD) Search Button About Welcome Overview Visiting the APS Mission & Goals Find People Organization Charts Committees Job Openings User Information...

387

Relic Crystal-Lattice Effects on Raman Compression of Powerful X-Ray Pulses in Plasmas V. M. Malkin and N. J. Fisch  

E-Print Network [OSTI]

.38.ÿr, 41.60.Cr, 42.55.Vc, 42.65.Re New mJ x-ray laser technologies [1­3] might produce attosecond laser optical laser technologies [4,5]. The currently projected durations of powerful x-ray pulsesRelic Crystal-Lattice Effects on Raman Compression of Powerful X-Ray Pulses in Plasmas V. M. Malkin

388

X-ray spectroscopy of neutron star low-mass X-ray binaries  

E-Print Network [OSTI]

In this thesis, I present work spanning a variety of topics relating to neutron star lowmass X-ray binaries (LMXBs) and utilize spectral information from X-ray observations to further our understanding of these sources. ...

Krauss, Miriam Ilana

2007-01-01T23:59:59.000Z

389

Ultraluminous X-ray Sources: The most extreme X-ray binaries  

E-Print Network [OSTI]

1 Ultraluminous X-ray Sources: The most extreme X-ray binaries Luca Zampieri INAF ULXs ­ Lubiana ­ May 11, 2012- LZ #12;6 · X-ray observations of nearby galaxies show a population of pointlike, off-nuclear sources with L >> Ledd for 1 Msun (L>1.0e39 erg/s) UltraLuminous X-ray Sources (e

Â?umer, Slobodan

390

X-ray Diffraction (XRD) 1.0 What is X-ray Diffraction  

E-Print Network [OSTI]

X-ray Diffraction (XRD) · 1.0 What is X-ray Diffraction · 2.0 Basics of Crystallography · 3.0 Production of X-rays · 4.0 Applications of XRD · 5.0 Instrumental Sources of Error · 6.0 Conclusions #12 why the cleavage faces of crystals appear to reflect X-ray beams at certain angles of incidence (theta

Moeck, Peter

391

Aneta Siemiginowska Chandra X-ray Center  

E-Print Network [OSTI]

-ray and gamma-ray · High Energy Sky · Chandra X-ray Observatory · examples of typical X-ray data, · an example of a data analysis process · statistical challenges · what do we learn from the data? #12;What is Astronomy and phenomena do we study and how? Solar System: Sun and sollar wind, planets, moons, asteroids, comets Our

Wolfe, Patrick J.

392

Watershed in X-ray Astronomy  

Science Journals Connector (OSTI)

... extent the article on page 96 of this issue of Nature from the X-ray astronomy group at the Massachusetts Institute of Technology is a record of disappointments. That is ... near the galactic centre. Now that the first satellite to be devoted to X-ray astronomy has been launched, and is apparently working successfully, the MIT article and another from ...

1971-01-08T23:59:59.000Z

393

X-Ray Identification of Element 104  

Science Journals Connector (OSTI)

The daughter x-ray identification technique has been applied to the identification of element 104. The characteristic K-series x rays from the ?-decay daughter isotope, nobelium (Z=102), have been observed in coincidence with ? particles from the decay of 4.5-sec 104257, thus providing an unequivocal determination of the parent atomic number, Z=104.

C. E. Bemis; Jr.; R. J. Silva; D. C. Hensley; O. L. Keller; Jr.; J. R. Tarrant; L. D. Hunt; P. F. Dittner; R. L. Hahn; C. D. Goodman

1973-09-03T23:59:59.000Z

394

Human genome sequencing with direct x-ray holographic imaging. Final report  

SciTech Connect (OSTI)

Direct holographic imaging of biological materials is widely applicable to the study of the structure, properties and action of genetic material. This particular application involves the sequencing of the human genome where prospective genomic imaging technology is composed of three subtechnologies, name an x-ray holographic camera, suitable chemistry and enzymology for the preparation of tagged DNA samples, and the illuminator in the form of an x-ray laser. We report appropriate x-ray camera, embodied by the instrument developed by MCR, is available and that suitable chemical and enzymatic procedures exist for the preparation of the necessary tagged DNA strands. Concerning the future development of the x-ray illuminator. We find that a practical small scale x-ray light source is indeed feasible. This outcome requires the use of unconventional physical processes in order to achieve the necessary power-compression in the amplifying medium. The understanding of these new physical mechanisms is developing rapidly. Importantly, although the x-ray source does not currently exist, the understanding of these new physical mechanisms is developing rapidly and the research has established the basic scaling laws that will determine the properties of the x-ray illuminator. When this x-ray source becomes available, an extremely rapid and cost effective instrument for 3-D imaging of biological materials can be applied to a wide range of biological structural assays, including the base-pair sequencing of the human genome and many questions regarding its higher levels of organization.

Rhodes, C.K.

1993-06-08T23:59:59.000Z

395

Quantitative Measurements of X-ray Intensity  

SciTech Connect (OSTI)

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.

Haugh, M. J., Schneider, M.

2011-09-01T23:59:59.000Z

396

Characterization of X-ray streak cameras for use on Nova  

SciTech Connect (OSTI)

There are many different types of measurements that require a continuous time history of x-ray emission that can be provided with an x-ray streak camera. In order to properly analyze the images that are recorded with the x-ray streak cameras operated on Nova, it is important to account for the streak characterization of each camera. We have performed a number of calibrations of the streak cameras both on the bench as well as with Nova disk target shots where we use a time modulated laser intensity profile (self-beating of the laser) on the target to generate an x-ray comb. We have measured the streak camera sweep direction and spatial offset, curvature of the electron optics, sweep rate, and magnification and resolution of the electron optics.

Kalantar, D.H.; Bell, P.M.; Costa, R.L.; Hammel, B.A.; Landen, O.L.; Orzechowski, T.J. [Lawrence Livermore National Lab., CA (United States); Hares, J.D.; Dymoke-Bradshaw, A.K.L. [Kentech Instruments Ltd., Didcot (United Kingdom)

1996-09-01T23:59:59.000Z

397

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

SciTech Connect (OSTI)

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.

Tanabe, Minoru; Nishimura, Hiroaki; Fujioka, Shinsuke; Nagai, Keiji; Yamamoto, Norimasa; Mima, Kunioki [Institute of Laser Engineering, Osaka University, 2-6 Yamada-Oka, Suita, Osaka 565-0871 (Japan); Gu, Zhong-Ze; Pan, Chao [State Key Laboratory of Bioelectronics, Southeast University, Nanjing, Jiangsu 210096 (China); Girard, Frederic; Primout, Michel; Villette, Bruno; Brebion, Didier [Commissariat a l'Energie Atomique, DAM-Ile-de-France, Bruyeres-le-Chatel, 91297 Arpajon, Cedex (France); Fournier, Kevin B. [Lawrence Livermore National Laboratory, P.O. Box 808, L-473, Livermore, California 94550 (United States); Fujishima, Akira [Kanagawa Academy of Science and Technology, 3-2-1 Sakato, Takatsu-ku, Kawasaki 213-0012 (Japan)

2008-08-04T23:59:59.000Z

398

International Conference on Surface X-ray and Neutron Scattering (SXNS-11)  

SciTech Connect (OSTI)

The 11th International Surface X-ray and Neutron Scattering (SXNS) Conference was held on July 13-17, 2010, on the Northwestern University (NU) campus, in Evanston Illinois and hosted by the NU Materials Research Science and Engineering Center. This biennial conference brought together a community of 164 attendees from 16 countries. The field now makes use of a broad range of new experimental capabilities that have been made possible through the development of increasingly brilliant X-ray and neutron sources around the world, including third generation synchrotron sources, neutron reactor and spallation sources, as well as the recent development of X-ray lasers.

Michael J. Bedzyk

2011-06-17T23:59:59.000Z

399

X-ray Practicals Series 1 Advanced Data Reduction  

E-Print Network [OSTI]

X-ray Practicals Series 1 Advanced Data Reduction Instructor J. Reibenspies, Ph. D. Nattamai Bhuvanesh, Ph.D. Version 1.0.0 #12;X-ray Practicals Series 2 #12;X-ray Practicals Series 3 #12;X-ray is good. The y direction is shifting the most, but the shift is ok #12;X-ray Practicals Series 5 Other

Meagher, Mary

400

Dense Plasma X-ray Scattering: Methods and Applications  

SciTech Connect (OSTI)

We have developed accurate x-ray scattering techniques to measure the physical properties of dense plasmas. Temperature and density are inferred from inelastic x-ray scattering data whose interpretation is model-independent for low to moderately coupled systems. Specifically, the spectral shape of the non-collective Compton scattering spectrum directly reflects the electron velocity distribution. In partially Fermi degenerate systems that have been investigated experimentally in laser shock-compressed beryllium, the Compton scattering spectrum provides the Fermi energy and hence the electron density. We show that forward scattering spectra that observe collective plasmon oscillations yield densities in agreement with Compton scattering. In addition, electron temperatures inferred from the dispersion of the plasmon feature are consistent with the ion temperature sensitive elastic scattering feature. Hence, theoretical models of the static ion-ion structure factor and consequently the equation of state of dense matter can be directly tested.

Glenzer, S H; Lee, H J; Davis, P; Doppner, T; Falcone, R W; Fortmann, C; Hammel, B A; Kritcher, A L; Landen, O L; Lee, R W; Munro, D H; Redmer, R; Weber, S

2009-08-19T23:59:59.000Z

Note: This page contains sample records for the topic "x-ray free-electron laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

New Developments in Femtosecond Soft X-ray Spectroscopy  

SciTech Connect (OSTI)

Recent instrumentation developments in X-ray spectroscopy for ultra-fast time-resolved measurements with soft X-rays done in HZB Berlin during the last years are described. The significant performance improvements achieved this way are based on Fresnel diffraction from structures being fabricated on a surface of a total externally reflecting mirror. The first type of this spectrometer, an off-axis reflection zone plate, has been implemented at the BESSY Femtoslicing setup and shows on the order of 20 times higher flux in the focal plane compared to the classical grating monochromator beamline. It has proven to serve very precise experiments with a time resolution down to 100 fs on magnetic materials after optical laser pulse excitation.

Erko, A.; Firsov, A.; Holldack, K. [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Elektronenspeicherring BESSY II, Albert Einstein str.15, Berlin (Germany)

2010-06-23T23:59:59.000Z

402

X-ray sources in globular clusters  

E-Print Network [OSTI]

The twelve bright (Lx>10(36) erg/s) X-ray sources in the globular clusters have lower luminosities than the brightest sources in the bulge of our galaxy. The dim (Lx<10(35) erg/s) X-ray sources in globular clusters reach higher luminosities than the cataclysmic variables in the disk of our galaxy. The first difference is a statistical fluke, as comparison with M31 indicates. The second difference is explained because the brightest of the dim sources are not cataclysmic variables, but soft X-ray transients in quiescence. This article describes the BeppoSAX, ROSAT and first Chandra observations leading to these conclusions.

Frank Verbunt

2001-11-22T23:59:59.000Z

403

X-RAY EMISSION FROM PLANETS AND COMETS: RELATIONSHIP WITH SOLAR X-RAYS AND SOLAR WIND  

E-Print Network [OSTI]

with the occurrence of solar X-ray flare, when light travel time delay is accounted, suggesting that X-rays fromX-RAY EMISSION FROM PLANETS AND COMETS: RELATIONSHIP WITH SOLAR X-RAYS AND SOLAR WIND ANIL BHARDWAJ Flight center, Greenbelt, MD 20771, USA Scattering of solar X-ray radiation mainly produces the non

Ã?stgaard, Nikolai

404

X-Ray Diffraction The X-Ray Diffraction facility is equipped with state-of-the-art  

E-Print Network [OSTI]

X-Ray Diffraction The X-Ray Diffraction facility is equipped with state-of-the-art diffractometers offering both single crystal and powder X-Ray diffraction. Powder X-Ray Diffraction High resolution data For more details on powder X-Ray analysis contact Dr J Hriljac on 0121 414 4458 or email: j

Birmingham, University of

405

Novel X-Ray Imaging Opportunities for the RPI Linear Accelerator's Tunable, Quasi-monochromatic X-ray Source  

E-Print Network [OSTI]

Novel X-Ray Imaging Opportunities for the RPI Linear Accelerator's Tunable, Quasi-monochromatic X-ray of an intense, tunable, polarized, and quasi-monochromatic X-ray source has been ongoing at Rensselaer Polytechnic Institute since 2001 [1, 2, 3, 4, 5, 6]. This X-ray source, known as Parametric X-rays (PXR

Danon, Yaron

406

X-ray Absorption Spectroscopy of Biologically Relevant Systems  

E-Print Network [OSTI]

308, Messer, B. M. X-ray Absorption Spectroscopy of AqueousSarcosine via X-ray Absorption Spectroscopy 5.1 Introductionwith Carboxylate by X-Ray Absorption Spectroscopy of Liquid

Uejio, Janel Sunayo

2010-01-01T23:59:59.000Z

407

Compact X-Ray Light Source Workshop | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Compact X-Ray Light Source Workshop Compact X-Ray Light Source Workshop Teller R, Terminello L, Thevuthasan T, Moncton D. 2012. "Compact X-Ray Light Source Workshop Report."...

408

Biological Imaging by Soft X-Ray Diffraction Microscopy  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Biological Imaging by Soft X-Ray Diffraction Microscopy Biological Imaging by Soft X-Ray Diffraction Microscopy Print Wednesday, 30 November 2005 00:00 Electron and x-ray...

409

A SOURCE OF COHERENT SOFT X-RAY RADIATION BASED ON HIGH-ORDER HARMONIC GENERATION AND FREE ELECTRON  

E-Print Network [OSTI]

at shorter wavelengths down to 4 nm is obtained by bunching the energy modulated electrons and passing ultraviolet (EUV) (see [1] and references therein). The repetition rate of these pulses depends been demon- strated with a repetition rate of the order of 1 kHz. Higher pulse energies have also been

Wurtele, Jonathan

410

APS Bending Magnet X-rays and  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Irradiation of Nd-Fe-B Permanent Magnets with Irradiation of Nd-Fe-B Permanent Magnets with APS Bending Magnet X-rays and 60 Co γ-rays J. Alderman and P.K. Job APS Operations Division Advanced Photon Source J. Puhl Ionizing Radiation Division National Institute of Standards and Technology June 2000 Table of Contents Introduction Radiation-Induced Demagnetization of Permanent Magnets Resources Required γ-ray Irradiation Results and Analysis of γ-ray Irradiation X-ray Irradiation Results and Analysis of X-ray Irradiation Summary and Conclusions Acknowledgements References Tables and Figures Introduction The Advanced Photon Source (APS), as well as other third-generation synchrotron light sources, uses permanent magnets in the insertion devices to produce x-rays for scientific

411

X-ray source for mammography  

DOE Patents [OSTI]

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

Logan, Clinton M. (Pleasanton, CA)

1994-01-01T23:59:59.000Z

412

Ultrafast X-Ray Sources and Science  

Science Journals Connector (OSTI)

X-ray science is entering the ultrafast and ultraintense era - spurred by developments in coherent, short-wavelength sources that range from tabletop to accelerator-based. These...

Young, Linda

413

SMB, X-ray Emission Spectroscopy  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Emission Spectroscopy Beam Line 6-2b X-ray Emission Spectroscopy Beam Line 6-2b is an advanced spectroscopy experimental station on the multidisciplinary general user wiggler Beam...

414

X-raying galaxies: A Chandra legacy  

Science Journals Connector (OSTI)

...Astronomy, University of Massachusetts, Amherst, MA 01003 This presentation...stellar x-ray sources in the solar neighborhood (8). The...elements—Meteoritic and solar . Geochim Cosmochim Acta 53...Astronomy, University of Massachusetts, Amherst, MA 01003, USA...

Q. Daniel Wang

2010-01-01T23:59:59.000Z

415

Small Angle X-Ray Scattering Detector  

DOE Patents [OSTI]

A detector for time-resolved small-angle x-ray scattering includes a nearly constant diameter, evacuated linear tube having an end plate detector with a first fluorescent screen and concentric rings of first fiber optic bundles for low angle scattering detection and an annular detector having a second fluorescent screen and second fiber optic bundles concentrically disposed about the tube for higher angle scattering detection. With the scattering source, i.e., the specimen under investigation, located outside of the evacuated tube on the tube's longitudinal axis, scattered x-rays are detected by the fiber optic bundles, to each of which is coupled a respective photodetector, to provide a measurement resolution, i.e., dq/q, where q is the momentum transferred from an incident x-ray to an x-ray scattering specimen, of 2% over two (2) orders of magnitude in reciprocal space, i.e., qmax/qmin approx=lO0.

Hessler, Jan P.

2004-06-15T23:59:59.000Z

416

X-Ray Nanoimaging: Instruments and Methods  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

X-Ray Nanoimaging: Instruments and Methods To be held as part of SPIE. http:spie.orgOP318 August 28-29, 2013; San Diego, California, USA...

417

Femtosecond X-ray protein nanocrystallography  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Femtosecond X-ray protein nanocrystallography Authors: Chapman, H.N., Fromme, P., Barty, A., White, T.A., Kirian, R.A., Aquila, A., Hunter, M.S., Schulz, J., DePonte, D.P.,...

418

X-ray source for mammography  

DOE Patents [OSTI]

An x-ray source is described utilizing anode material which shifts the output spectrum to higher energy and thereby obtains higher penetrating ability for screening mammography application, than the currently utilized anode material. The currently used anode material (molybdenum) produces an energy x-ray spectrum of 17.5/19.6 keV, which using the anode material of this invention (e.g. silver, rhodium, and tungsten) the x-ray spectrum would be in the 20-35 keV region. Thus, the anode material of this invention provides for imaging of breasts with higher than average x-ray opacity without increase of the radiation dose, and thus reduces the risk of induced breast cancer due to the radiation dose administered for mammograms. 6 figures.

Logan, C.M.

1994-12-20T23:59:59.000Z

419

THE CORRELATION BETWEEN DISPERSION MEASURE AND X-RAY COLUMN DENSITY FROM RADIO PULSARS  

SciTech Connect (OSTI)

Pulsars are remarkable objects that emit across the entire electromagnetic spectrum, providing a powerful probe of the interstellar medium. In this study, we investigate the relation between dispersion measure (DM) and X-ray absorption column density N{sub H} using 68 radio pulsars detected at X-ray energies with the Chandra X-Ray Observatory or XMM-Newton. We find a best-fit empirical linear relation of N{sub H} (10{sup 20} cm{sup -2})= 0.30{sup +0.13}{sub -0.09} DM (pc cm{sup -3}), which corresponds to an average ionization of 10{sup +4}{sub -3}%, confirming the ratio of one free electron per 10 neutral hydrogen atoms commonly assumed in the literature. We also compare different N{sub H} estimates and note that some N{sub H} values obtained from X-ray observations are higher than the total Galactic H I column density along the same line of sight, while the optical extinction generally gives the best N{sub H} predictions.

He, C.; Ng, C.-Y.; Kaspi, V. M., E-mail: ncy@bohr.physics.hku.hk [Department of Physics, McGill University, Montreal, QC H3A 2T8 (Canada)

2013-05-01T23:59:59.000Z

420

Lasers without Mirrors, Designed by Supercomputer - NERSC SCience News  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Lasers without Lasers without Mirrors, Designed by Supercomputer Lasers without Mirrors, Designed by Supercomputer October 14, 2009 | Tags: Lasers, Life Sciences, Materials Science Contact: Ji Qiang | Lawrence Berkeley National Laboratory | JQiang@lbl.gov John Corlett | Lawrence Berkeley National Laboratory, Center for Beam Physics | JNCorlett@lbl.gov Sometimes it takes a big machine to understand the tiniest details. That's the case with free electron lasers (FELs). The powerful X-rays they generate can probe matter directly at the level of atomic interactions and chemical-bond formation, letting scientists observe such phenomena as chemical reactions in trace elements, electric charges in photosynthesis and the structure of microscopic machines. FELs have the potential to

Note: This page contains sample records for the topic "x-ray free-electron laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Using X-Ray Computed Tomography in Pore Structure Characterization...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Using X-Ray Computed Tomography in Pore Structure Characterization for a Berea Sandstone: Resolution Effect. Using X-Ray Computed Tomography in Pore Structure Characterization for...

422

Argonne CNM: X-Ray Microscopy Capabilities  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

X-Ray Microscopy Facilities X-Ray Microscopy Facilities The Hard X-Ray Nanoprobe (HXN) facility provides scanning fluorescence, scanning diffraction, and full-field transmission and tomographic imaging capabilities with a spatial resolution of 30 nm over a spectral range of 6-12 keV. Modes of Operation Full-Field Transmission Imaging and Nanotomography X-ray transmission imaging uses both the absorption and phase shift of the X-ray beam by the sample as contrast mechanisms. Absorption contrast is used to map the sample density. Elemental constituents can be located by using differential edge contrast in this mode. Phase contrast can be highly sensitive to edges and interfaces even when the X-ray absorption is weak. These contrast mechanisms are exploited to image samples rapidly in full-field transmission mode under various environmental conditions, or combined with nanotomography methods to study the three-dimensional structure of complex and amorphous nanomaterials with the HXN.

423

The Constellation X-ray mission  

Science Journals Connector (OSTI)

The Constellation-X mission is a large collecting area X-ray facility, emphasizing observations at high spectral resolution (E/?E?300–3000) while covering a broad energy band (0.25–40 keV). By increasing the telescope aperture and utilizing efficient spectrometers the mission will achieve a factor of 100 increased sensitivity over current high-resolution X-ray spectroscopy missions. The use of focussing optics across the 10–40 keV band will provide a similar factor of 100 increased sensitivity in this band. Key technologies under development for the mission include lightweight high throughput X-ray optics, multilayer coatings to enhance the hard X-ray performance of X-ray optics, micro-calorimeter spectrometer arrays with 2 eV resolution, low-power and low-weight CCD arrays, lightweight gratings and hard X-ray detectors. When observations commence towards the end of the next decade, Constellation-X will address many pressing questions concerning the extremes of gravity and the evolution of the Universe.

N.E White; H Tananbaum

1999-01-01T23:59:59.000Z

424

X-Ray Observations of Radio Galaxies  

E-Print Network [OSTI]

We review some of the ways that X-ray observations provide unique information on radio galaxies. Thermal bremsstrahlung X-ray emission provides detailed data on ambient densities and temperatures. These parameters in turn can be used for pressure balance calculations and can demonstrate how the ambient gas affects radio source structure. Additionally, many signatures of the interaction of radio jets and lobes with the hot gas are found in high resolution X-ray maps. Non-thermal X-ray emission from knots and hotspots of radio jets can give us constraints on the relativistic electron population for energies greater that that normally sampled in the radio (in the case of synchrotron emission) or can give us an independent estimate of the average magnetic field strength (if inverse Compton emission is the origin of the X-rays). From recent ROSAT HRI observations of 3C 390.3 and 3C 120, we show evidence that X-ray emission from knots and hotspots appears to be associated with regions of large gradients in the radio surface brightness; i.e. at the location of powerful shocks.

D. E. Harris

1998-04-20T23:59:59.000Z

425

Development of x-ray laminography under an x-ray microscopic condition  

SciTech Connect (OSTI)

An x-ray laminography system under an x-ray microscopic condition was developed to obtain a three-dimensional structure of laterally-extended planar objects which were difficult to observe by x-ray tomography. An x-ray laminography technique was introduced to an x-ray transmission microscope with zone plate optics. Three prototype sample holders were evaluated for x-ray imaging laminography. Layered copper grid sheets were imaged as a laminated sample. Diatomite powder on a silicon nitride membrane was measured to confirm the applicability of this method to non-planar micro-specimens placed on the membrane. The three-dimensional information of diatom shells on the membrane was obtained at a spatial resolution of sub-micron. Images of biological cells on the membrane were also obtained by using a Zernike phase contrast technique.

Hoshino, Masato; Uesugi, Kentaro; Takeuchi, Akihisa; Suzuki, Yoshio; Yagi, Naoto [Japan Synchrotron Radiation Research Institute JASRI/SPring-8, 1-1-1 Kouto, Sayo, Hyogo 679-5198 (Japan)

2011-07-15T23:59:59.000Z

426

X-ray views of neutron star low-mass X-ray binaries  

E-Print Network [OSTI]

A neutron star low-mass X-ray binary is a binary stellar system with a neutron star and a low-mass companion star rotating around each other. In this system the neutron star accretes mass from the companion, and as this matter falls into the deep potential well of the neutron star, the gravitational potential energy is released primarily in the X-ray wavelengths. Such a source was first discovered in X-rays in 1962, and this discovery formally gave birth to the "X-ray astronomy". In the subsequent decades, our knowledge of these sources has increased enormously by the observations with several X-ray space missions. Here we give a brief overview of our current understanding of the X-ray observational aspects of these systems.

Sudip Bhattacharyya

2010-02-24T23:59:59.000Z

427

Apparatus for generating x-ray holograms  

DOE Patents [OSTI]

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.

Rhodes, Charles K. (Chicago, IL); Boyer, Keith (Los Alamos, NM); Solem, Johndale C. (Los Alamos, NM); Haddad, Waleed S. (Chicago, IL)

1990-01-01T23:59:59.000Z

428

Apparatus for generating x-ray holograms  

DOE Patents [OSTI]

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.

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

1990-09-11T23:59:59.000Z

429

Is linear response to x-rays suitable for digital dental x-ray imaging systems? —Theoretical and experimental considerations  

Science Journals Connector (OSTI)

The purpose of this study was to consider theoretically and experimentally the suitability of linear response to x-rays for digital dental x-ray imaging systems.

Keiichi Nishikawa PhD; Mamoru Wakoh DDS; PhD; Kinya Kuroyanagi DDS; PhD

2003-06-01T23:59:59.000Z

430

MULTI-KEV X-RAY YIELDS FROM HIGH-Z GAS TARGETS FIELDED AT OMEGA  

SciTech Connect (OSTI)

The authors report on modeling of x-ray yield from gas-filled targets shot at the OMEGA laser facility. The OMEGA targets were 1.8 mm long, 1.95 mm in diameter Be cans filled with either a 50:50 Ar:Xe mixture, pure Ar, pure Kr or pure Xe at {approx} 1 atm. The OMEGA experiments heated the gas with 20 kJ of 3{omega} ({approx} 350 nm) laser energy delivered in a 1 ns square pulse. the emitted x-ray flux was monitored with the x-ray diode based DANTE instruments in the sub-keV range. Two-dimensional x-ray images (for energies 3-5 keV) of the targets were recorded with gated x-ray detectors. The x-ray spectra were recorded with the HENWAY crystal spectrometer at OMEGA. Predictions are 2D r-z cylindrical with DCA NLTE atomic physics. Models generally: (1) underpredict the Xe L-shell yields; (2) overpredict the Ar K-shell yields; (3) correctly predict the Xe thermal yields; and (4) greatly underpredict the Ar thermal yields. However, there are spreads within the data, e.g. the DMX Ar K-shell yields are correctly predicted. The predicted thermal yields show strong angular dependence.

Kane, J O; Fournier, K B; May, M J; Colvin, J D; Thomas, C A; Marrs, R E; Compton, S M; Moody, J D; Bond, E J; Davis, J F

2010-11-04T23:59:59.000Z

431

X-ray Pinhole Camera Measurements  

SciTech Connect (OSTI)

The development of the rod pinch diode [1] has led to high-resolution radiography for dynamic events such as explosive tests. Rod pinch diodes use a small diameter anode rod, which extends through the aperture of a cathode plate. Electrons borne off the aperture surface can self-insulate and pinch onto the tip of the rod, creating an intense, small x-ray source (Primary Pinch). This source has been utilized as the main diagnostic on numerous experiments that include high-value, single-shot events. In such applications there is an emphasis on machine reliability, x-ray reproducibility, and x-ray quality [2]. In tests with the baseline rod pinch diode, we have observed that an additional pinch (Secondary Pinch) occurs at the interface near the anode rod and the rod holder. This suggests that stray electrons exist that are not associated with the Primary Pinch. In this paper we present measurements on both pinches using an x-ray pinhole camera. The camera is placed downstream of the Primary Pinch at an angle of 60° with respect to the diode centerline. This diagnostic will be employed to diagnose x-ray reproducibility and quality. In addition, we will investigate the performance of hybrid diodes relating to the formation of the Primary and Secondary Pinches.

Nelson, D. S. [NSTec; Berninger, M. J. [NSTec; Flores, P. A. [NSTec; Good, D. E. [NSTec; Henderson, D. J. [NSTec; Hogge, K. W. [NSTec; Huber, S. R. [NSTec; Lutz, S. S. [NSTec; Mitchell, S. E. [NSTec; Howe, R. A. [NSTec; Mitton, C. V. [NSTec; Molina, I. [NSTec; Bozman, D. R. [SNL; Cordova, S. R. [SNL; Mitchell, D. R. [SNL; Oliver, B. V. [SNL; Ormond, E. C. [SNL

2013-07-01T23:59:59.000Z

432

X-ray lithography using holographic images  

DOE Patents [OSTI]

Methods for forming X-ray images having 0.25 {micro}m minimum line widths on X-ray sensitive material are presented. A holographic image of a desired circuit pattern is projected onto a wafer or other image-receiving substrate to allow recording of the desired image in photoresist material. In one embodiment, the method uses on-axis transmission and provides a high flux X-ray source having modest monochromaticity and coherence requirements. A layer of light-sensitive photoresist material on a wafer with a selected surface is provided to receive the image(s). The hologram has variable optical thickness and variable associated optical phase angle and amplitude attenuation for transmission of the X-rays. A second embodiment uses off-axis holography. The wafer receives the holographic image by grazing incidence reflection from a hologram printed on a flat metal or other highly reflecting surface or substrate. In this second embodiment, an X-ray beam with a high degree of monochromaticity and spatial coherence is required. 15 figs.

Howells, M.S.; Jacobsen, C.

1997-03-18T23:59:59.000Z

433

Oscillations During Thermonuclear X-ray Bursts  

E-Print Network [OSTI]

High amplitude, nearly coherent X-ray brightness oscillations during thermonuclear X-ray bursts were discovered with the Rossi X-ray Timing Explorer (RXTE) in early 1996. Spectral and timing evidence strongly supports the conclusion that these oscillations are caused by rotational modulation of the burst emission and that they reveal the spin frequency of neutron stars in low mass X-ray binaries, a long sought goal of X-ray astronomy. Studies carried out over the past year have led to the discovery of burst oscillations in four new sources, bringing to ten the number with confirmed burst oscillations. I review the status of our knowledge of these oscillations and indicate how they can be used to probe the physics of neutron stars. For a few burst oscillation sources it has been proposed that the strongest and most ubiquitous frequency is actually the first overtone of the spin frequency and hence that two nearly antipodal hot spots are present on the neutron star. This inference has important implications for both the physics of thermonuclear burning as well as the mass - radius relation for neutron stars, so its confirmation is crucial. I discuss recent attempts to confirm this hypothesis for 4U 1636-53, the source for which a signal at the putative fundamental (290 Hz) has been claimed.

Tod E. Strohmayer

2001-01-12T23:59:59.000Z

434

X-ray lithography using holographic images  

DOE Patents [OSTI]

Methods for forming X-ray images having 0.25 .mu.m minimum line widths on X-ray sensitive material are presented. A holgraphic image of a desired circuit pattern is projected onto a wafer or other image-receiving substrate to allow recording of the desired image in photoresist material. In one embodiment, the method uses on-axis transmission and provides a high flux X-ray source having modest monochromaticity and coherence requirements. A layer of light-sensitive photoresist material on a wafer with a selected surface is provided to receive the image(s). The hologram has variable optical thickness and variable associated optical phase angle and amplitude attenuation for transmission of the X-rays. A second embodiment uses off-axis holography. The wafer receives the holographic image by grazing incidence reflection from a hologram printed on a flat metal or other highly reflecting surface or substrate. In this second embodiment, an X-ray beam with a high degree of monochromaticity and spatial coherence is required.

Howells, Malcolm S. (Berkeley, CA); Jacobsen, Chris (Sound Beach, NY)

1997-01-01T23:59:59.000Z

435

Predicted X-ray backgrounds for the International X-ray Observatory  

E-Print Network [OSTI]

The background that will be observed by IXO's X-ray detectors naturally separates into two components: (1) a Cosmic X-ray Background (CXB), primarily due to unresolved point sources at high energies (E>2 keV), along with ...

Bautz, Marshall W.

436

Reflection soft X-ray microscope and method  

DOE Patents [OSTI]

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.

Suckewer, Szymon (Princeton, NJ); Skinner, Charles H. (Lawrenceville, NJ); Rosser, Roy (Princeton, NJ)

1993-01-01T23:59:59.000Z

437

Differential phase contrast X-ray imaging system and components  

DOE Patents [OSTI]

A differential phase contrast X-ray imaging system includes an X-ray illumination system, a beam splitter arranged in an optical path of the X-ray illumination system, and a detection system arranged in an optical path to detect X-rays after passing through the beam splitter.

Stutman, Daniel; Finkenthal, Michael

2014-07-01T23:59:59.000Z

438

Titanium and germanium lined hohlraums and halfraums as multi-keV x-ray radiators  

Science Journals Connector (OSTI)

As multi-keV x-ray radiators hohlraums and halfraums with inner walls coated with metallic materials (called liner) have been tested for the first time with laser as the energy drive. For titanium conversion efficiencies (CEs) are up to ? 14 % for emission into 4 ? integrating between 4.6 and 6.5 keV when a large diameter hohlraum is used. Germanium CE is ? 0.8 % into 4 ? between 9 and 13 keV. The highest CEs have been obtained with a 1 ns squared pulse and phase plates giving laser absorption near 99%. These high CEs are due to long-lasting good plasma conditions for multi-keV x-ray production maintained by plasma confinement inside the plastic cylinder and plasma collision leading to a burst of x rays at a time that depends on target size. As photon emitters at 4.7 keV titanium-lined hohlraums are the most efficient solid targets and data are close to CEs for gas targets which are considered as the upper limit for x-ray yields since their low density allows good laser absorption and low kinetics losses. As 10.3 keV x-ray emitters exploded germanium foils give best results one order of magnitude more efficient than thick targets; doped aerogels and lined hohlraums give similar yields about three times lower than those from exploded foils.

F. Girard; M. Primout; B. Villette; Ph. Stemmler; L. Jacquet; D. Babonneau; K. B. Fournier

2009-01-01T23:59:59.000Z

439

X-ray variability in M87  

E-Print Network [OSTI]

We present the evidence for X-ray variability from the core and from knot A in the M87 jet based on data from two observations with the Einstein Observatory High Resolution Imager (HRI) and three observations with the ROSAT HRI. The core intensity showed a 16% increase in 17 months ('79-'80); a 12% increase in the 3 years '92 to '95; and a 17% drop in the last half of 1995. The intensity of knot A appears to have decreased by 16% between 92Jun and 95Dec. Although the core variability is consistent with general expectations for AGN nuclei, the changes in knot A provide constraints on the x-ray emission process and geometry. Thus we predict that the x-ray morphology of knot A will differ significantly from the radio and optical structure.

D. E. Harris; J. A. Biretta; W. Junor

1996-12-05T23:59:59.000Z

440

Displaced Vertices from X-ray Lines  

E-Print Network [OSTI]

We present a simple model of weak-scale thermal dark matter that gives rise to X-ray lines. Dark matter consists of two nearly degenerate states near the weak scale, which are populated thermally in the early universe via co-annihilation with slightly heavier states that are charged under the Standard Model. The X-ray line arises from the decay of the heavier dark matter component into the lighter one via a radiative dipole transition, at a rate that is slow compared to the age of the universe. The model predicts observable signatures at the LHC in the form of exotic events with missing energy and displaced leptons and jets. As an application, we show how this model can explain the recently observed 3.55 keV X-ray line.

Adam Falkowski; Yonit Hochberg; Joshua T. Ruderman

2014-09-09T23:59:59.000Z

Note: This page contains sample records for the topic "x-ray free-electron laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

X-ray focal spot locating apparatus and method  

DOE Patents [OSTI]

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.

Gilbert, Hubert W. (Cedar Crest, NM)

1985-07-30T23:59:59.000Z

442

X-ray Science Division: Groups  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Division: Groups Division: Groups Atomic, Molecular and Optical Physics (AMO) Primary Contact: Stephen Southworth Work focuses on understanding how strong optical and x-ray fields interact with matter, with an emphasis on photonic control of electronic, atomic and molecular motion. Chemical and Materials Science (CMS) Primary Contact: Randy Winans Research Disciplines: Chemistry, Materials Science Detectors (DET) Primary Contact: Antonino Miceli GMCA Structural Biology Facility (MX) Primary Contact: Robert Fischetti Research Disciplines: Biology, Life Sciences Imaging (IMG) Primary Contact: Francesco DeCarlo Research Disciplines: Materials Science, Biology, Physics, Life Sciences Inelastic X-ray & Nuclear Resonant Scattering (IXN) Primary Contact: Thomas Gog Research Disciplines: Condensed Matter Physics, Geophysics, Materials

443

Cosmology with X-ray Cluster Baryons  

SciTech Connect (OSTI)

X-ray cluster measurements interpreted with a universal baryon/gas mass fraction can theoretically serve as a cosmological distance probe. We examine issues of cosmological sensitivity for current (e.g., Chandra X-ray Observatory, XMM-Newton) and next generation (e.g., Con-X, XEUS) observations, along with systematic uncertainties and biases. To give competitive next generation constraints on dark energy, we find that systematics will need to be controlled to better than 1percent and any evolution in f_gas (and other cluster gas properties) must be calibrated so the residual uncertainty is weaker than (1+z)0.03.

Linder, Eric V.

2007-04-10T23:59:59.000Z

444

Phase recovery for x-ray crystallography  

Science Journals Connector (OSTI)

For many years people have believed that in conventional x-ray crystallography one can only record the diffraction intensities but not the phases. In order to obtain the atomic arrangements, one usually has to guess a structure and then fit the intensity data by refining its parameters. Here, we show that the phases are in fact hidden in the intensity data, and can be directly recovered from the peak profiles. This method is demonstrated by the normal two-beam x-ray diffraction of a noncentrosymmetric crystal, and nontrivial phases are recovered from the intensity data alone.

G. Xu, G. E. Zhou, and X. Y. Zhang

1999-04-01T23:59:59.000Z

445

Sharper Focusing of Hard X-rays  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Sharper Focusing of Hard X-rays FROM: Physics News Update Number 773 #1, April 12, 2006, by Phil Schewe and Ben Stein Note: This text has been slightly modified from the original. Sharper focusing of hard x-rays has been achieved with a device developed at Argonne National Lab. Because of their high energy, x-rays are hard to focus: they can be reflected from a surface but only at a glancing angle (less than a tenth of a degree); they can be refracted but the index of refraction is very close to 1, so that making efficient lenses becomes a problem; and they can be diffracted, but the relatively thick, variable pitch grating required for focusing is tricky to achieve. The Argonne device is of the diffraction type, and it consists of a stack of alternating layers of metal and silicon, made by depositing progressively thicker layers. When the x-rays fall on such a structure, nearly edge-on, what they see is a grating (called a linear zone plate) consisting of a sort of bar-code pattern.

446

Radioactive Thulium for X-Rays  

Science Journals Connector (OSTI)

Radioactive power from thulium makes Argonne x-ray unit a potential for medical and industrial use ... Active component of the instrument is a tiny particle (one-fifth gram) of thulium-170 which has been made radioactive in a heavy water nuclear reactor at Arco, Idaho. ...

1954-05-03T23:59:59.000Z

447

X-ray spectroscopy of manganese clusters  

SciTech Connect (OSTI)

Much of this thesis represents the groundwork necessary in order to probe Mn clusters more productively than with conventional Mn K-edge XAS and is presented in Part 1. Part 2 contains the application of x-ray techniques to Mn metalloproteins and includes a prognosis at the end of each chapter. Individual Mn oxidation states are more readily distinguishable in Mn L-edge spectra. An empirical mixed valence simulation routine for determining the average Mn oxidation state has been developed. The first Mn L-edge spectra of a metalloprotein were measured and interpreted. The energy of Mn K{beta} emission is strongly correlated with average Mn oxidation state. K{beta} results support oxidation states of Mn(III){sub 2}(IV){sub 2} for the S{sub 1} state of Photosystem II chemical chemically reduced preparations contain predominantly Mn(II). A strength and limitation of XAS is that it probes all of the species of a particular element in a sample. It would often be advantageous to selectively probe different forms of the same element. The first demonstration that chemical shifts in x-ray fluorescence energies can be used to obtain oxidation state-selective x-ray absorption spectra is presented. Spin-dependent spectra can also be used to obtain a more simplified picture of local structure. The first spin-polarized extended x-ray absorption fine structure using Mn K{beta} fluorescence detection is shown.

Grush, M.M. [Univ. of California, Davis, CA (United States). Dept. of Applied Science; [Lawrence Berkeley National Lab., CA (United States). Energy and Environment Div.

1996-06-01T23:59:59.000Z

448

Multiple wavelength X-ray monochromators  

DOE Patents [OSTI]

An improved apparatus and method is provided for separating input x-ray radiation containing first and second x-ray wavelengths into spatially separate first and second output radiation which contain the first and second x-ray wavelengths, respectively. The apparatus includes a crystalline diffractor which includes a first set of parallel crystal planes, where each of the planes is spaced a predetermined first distance from one another. The crystalline diffractor also includes a second set of parallel crystal planes inclined at an angle with respect to the first set of crystal planes where each of the planes of the second set of parallel crystal planes is spaced a predetermined second distance from one another. In one embodiment, the crystalline diffractor is comprised of a single crystal. In a second embodiment, the crystalline diffractor is comprised of a stack of two crystals. In a third embodiment, the crystalline diffractor includes a single crystal that is bent for focusing the separate first and second output x-ray radiation wavelengths into separate focal points. 3 figs.

Steinmeyer, P.A.

1992-11-17T23:59:59.000Z

449

Small Angle X-Ray Scattering Detector  

DOE Patents [OSTI]

A detector for time-resolved small-angle x-ray scattering includes a nearly constant diameter, evacuated linear tube having an end plate detector with a first fluorescent screen and concentric rings of first fiber optic bundles for low angle scattering detection and an annular detector having a second fluorescent screen and second fiber optic bundles concentrically disposed about the tube for higher angle scattering detection. With the scattering source, i.e., the specimen under investigation, located outside of the evacuated tube on the tube's longitudinal axis, scattered x-rays are detected by the fiber optic bundles, to each of which is coupled a respective photodetector, to provide a measurement resolution, i.e., dq/q, where q is the momentum transferred from an incident x-ray to an x-ray scattering specimen, of 2% over two (2) orders of magnitude in reciprocal space, i.e., q.sub.max /q.sub.min.congruent.100.

Hessler, Jan P. (Downers Grove, IL)

2004-06-15T23:59:59.000Z

450

SLAC All Access: X-ray Microscope  

ScienceCinema (OSTI)

SLAC physicists Johanna Nelson and Yijin Liu give a brief overview of the X-ray microscope at the Stanford Synchrotron Radiation Lightsource (SSRL) that is helping improve rechargeable-battery technology by letting researchers peek into the inner workings of batteries as they operate.

Nelson, Johanna; Liu, Yijin

2014-06-13T23:59:59.000Z

451

Leading U.S. X-ray Source Goes After Bigger Upgrade  

Science Journals Connector (OSTI)

...of 3-meter-long dipole magnets would be replaced with a string of five to eight shorter ones. That change should shrink the...The beams would also be coherent, with the x-ray photons oscillating in lockstep like those in a laser beam. Coherent beams would...

Adrian Cho

2014-01-03T23:59:59.000Z

452

Synchrotron x-ray fluorescence and extended x-ray absorption fine structure analysis  

SciTech Connect (OSTI)

The advent of dedicated synchrotron radiation sources has led to a significant increase in activity in many areas of science dealing with the interaction of x-rays with matter. Synchrotron radiation provides intense, linearly polarized, naturally collimated, continuously tunable photon beams, which are used to determine not only the elemental composition of a complex, polyatomic, dilute material but also the chemical form of the elements with improved accuracy. Examples of the application of synchrotron radiation include experiments in synchrotron x-ray fluorescence (SXRF) analysis and extended x-ray absorption fine structure (EXAFS) analysis. New synchrotron radiation x-ray microprobes for elemental analysis in the parts per billion range are under construction at several laboratories. 76 references, 24 figures.

Chen, J.R.; Gordon, B.M.; Hanson, A.L.; Jones, K.W.; Kraner, H.W.; Chao, E.C.T.; Minkin, J.A.

1984-01-01T23:59:59.000Z

453

X-ray imaging crystal spectrometer for extended X-ray sources  

DOE Patents [OSTI]

Spherically or toroidally curved, double focusing crystals are used in a spectrometer for X-ray diagnostics of an extended X-ray source such as a hot plasma produced in a tokomak fusion experiment to provide spatially and temporally resolved data on plasma parameters using the imaging properties for Bragg angles near 45. For a Bragg angle of 45.degree., the spherical crystal focuses a bundle of near parallel X-rays (the cross section of which is determined by the cross section of the crystal) from the plasma to a point on a detector, with parallel rays inclined to the main plain of diffraction focused to different points on the detector. Thus, it is possible to radially image the plasma X-ray emission in different wavelengths simultaneously with a single crystal.

Bitter, Manfred L. (Princeton, NJ); Fraenkel, Ben (Jerusalem, IL); Gorman, James L. (Bordentown, NJ); Hill, Kenneth W. (Lawrenceville, NJ); Roquemore, A. Lane (Cranbury, NJ); Stodiek, Wolfgang (Princeton, NJ); von Goeler, Schweickhard E. (Princeton, NJ)

2001-01-01T23:59:59.000Z

454

Rise Time Measurement for Ultrafast X-Ray Pulses  

DOE Patents [OSTI]

A pump-probe scheme measures the rise time of ultrafast x-ray pulses. Conventional high speed x-ray diagnostics (x-ray streak cameras, PIN diodes, diamond PCD devices) do not provide sufficient time resolution to resolve rise times of x-ray pulses on the order of 50 fs or less as they are being produced by modern fast x-ray sources. Here, we are describing a pump-probe technique that can be employed to measure events where detector resolution is insufficient to resolve the event. The scheme utilizes a diamond plate as an x-ray transducer and a p-polarized probe beam.

Celliers, Peter M.; Weber, Franz A.; Moon, Stephen J.

2005-04-05T23:59:59.000Z

455

X-ray microscopy using grazing-incidence reflection optics  

SciTech Connect (OSTI)

The Kirkpatrick-Baez microscopes are described along with their role as the workhorse of the x-ray imaging devices. This role is being extended with the development of a 22X magnification Kirkpatrick-Baez x-ray microscope with multilayer x-ray mirrors. These mirrors can operate at large angles, high x-ray energies, and have a narrow, well defined x-ray energy bandpass. This will make them useful for numerous experiments. However, where a large solid angle is needed, the Woelter microscope will still be necessary and the technology needed to build them will be useful for many other types of x-ray optics.

Price, R.H.

1981-08-06T23:59:59.000Z

456

X-RAY POINT-SOURCE POPULATIONS CONSTITUTING THE GALACTIC RIDGE X-RAY EMISSION  

SciTech Connect (OSTI)

Apparently diffuse X-ray emission has been known to exist along the central quarter of the Galactic Plane since the beginning of X-ray astronomy; this is referred to as the Galactic Ridge X-ray emission (GRXE). Recent deep X-ray observations have shown that numerous X-ray point sources account for a large fraction of the GRXE in the hard band (2-8 keV). However, the nature of these sources is poorly understood. Using the deepest X-ray observations made in the Chandra bulge field, we present the result of a coherent photometric and spectroscopic analysis of individual X-ray point sources for the purpose of constraining their nature and deriving their fractional contributions to the hard-band continuum and Fe K line emission of the GRXE. Based on the X-ray color-color diagram, we divided the point sources into three groups: A (hard), B (soft and broad spectrum), and C (soft and peaked spectrum). The group A sources are further decomposed spectrally into thermal and non-thermal sources with different fractions in different flux ranges. From their X-ray properties, we speculate that the group A non-thermal sources are mostly active galactic nuclei and the thermal sources are mostly white dwarf (WD) binaries such as magnetic and non-magnetic cataclysmic variables (CVs), pre-CVs, and symbiotic stars, whereas the group B and C sources are X-ray active stars in flares and quiescence, respectively. In the log N-log S curve of the 2-8 keV band, the group A non-thermal sources are dominant above Almost-Equal-To 10{sup -14} erg cm{sup -2} s{sup -1}, which is gradually taken over by Galactic sources in the fainter flux ranges. The Fe K{alpha} emission is mostly from the group A thermal (WD binaries) and the group B (X-ray active stars) sources.

Morihana, Kumiko [Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)] [Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Tsujimoto, Masahiro; Ebisawa, Ken [Japan Aerospace Exploration Agency, Institute of Space and Astronautical Science, 3-1-1 Yoshino-dai, Chuo-ku, Sagamihara, Kanagawa 252-5210 (Japan)] [Japan Aerospace Exploration Agency, Institute of Space and Astronautical Science, 3-1-1 Yoshino-dai, Chuo-ku, Sagamihara, Kanagawa 252-5210 (Japan); Yoshida, Tessei, E-mail: morihana@crab.riken.jp [National Astronomical Observatory of Japan, 2-21-1, Osawa, Mitaka, Tokyo 181-8588 (Japan)] [National Astronomical Observatory of Japan, 2-21-1, Osawa, Mitaka, Tokyo 181-8588 (Japan)

2013-03-20T23:59:59.000Z

457

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

SciTech Connect (OSTI)

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

Rubio-Zuazo, Juan; Castro, German R. [SpLine, Spanish CRG beamline at the European Synchrotron Radiation Facility, B.P. 220, F-38043 Grenoble (France) and ICMM-CSIC Cantoblanco, E-28049 Madrid (Spain)

2013-05-15T23:59:59.000Z

458

Femtosecond Single-Shot Imaging of Nanoscale Ferromagnetic Order in Co/Pd Multilayers using Resonant X-ray Holography  

SciTech Connect (OSTI)

We present the first single-shot images of ferromagnetic, nanoscale spin order taken with femtosecond x-ray pulses. X-ray-induced electron and spin dynamics can be outrun with pulses shorter than 80 fs in the investigated fluence regime, and no permanent aftereffects in the samples are observed below a fluence of 25 mJ/cm{sup 2}. Employing resonant spatially-muliplexed x-ray holography results in a low imaging threshold of 5 mJ/cm{sup 2}. Our results open new ways to combine ultrafast laser spectroscopy with sequential snapshot imaging on a single sample, generating a movie of excited state dynamics.

Wang, Tianhan; Zhu, Diling; Benny Wu,; Graves, Catherine; Schaffert, Stefan; Rander, Torbjorn; Muller, leonard; Vodungbo, Boris; Baumier, Cedric; Bernstein, David P.; Brauer, Bjorn; Cros, Vincent; Jong, Sanne de; Delaunay, Renaud; Fognini, Andreas; Kukreja, Roopali; Lee, Sooheyong; Lopez-Flores, Victor; Mohanty, Jyoti; Pfau, Bastian; Popescu, 5 Horia

2012-05-15T23:59:59.000Z

459

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

SciTech Connect (OSTI)

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.

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

2008-06-12T23:59:59.000Z

460

Casimir self-energy of a free electron  

E-Print Network [OSTI]

We derive the electromagnetic self-energy and the radiative correction to the gyromagnetic ratio of a free electron using a Casimir energy approach. This method provides an attractive and straightforward physical basis for the renormalization process.

Allan Rosencwaig

2006-06-23T23:59:59.000Z

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461

Tunable, Nanoscale Free-Electron Source of Photons and Plasmons  

Science Journals Connector (OSTI)

The passage of a free-electron beam through a nano-hole in a periodically layered metal/dielectric structure creates a new type of tuneable, nanoscale radiation source, analogous to...

Adamo, G; MacDonald, K F; Zheludev, N I; Fu, Y H; Wang, C -m; Tsai, D P; García de Abajo, F J

462

X-rays Illuminate Ancient Archimedes Text  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Related Links: Related Links: May 2005 Headlines TIP Article Press Release Walters Art Museum SSRL Home Page SLAC Home Page Stanford Home Page Tuesday, 31 May 2005 X-rays Illuminate Ancient Archimedes Text (contact: Uwe Bergmann, bergmann@slac.stanford.edu) Archimedes Figure Image provided by Will Noel, The Walters Art Museum An early transcription of Archimedes' mathematical theories has been brought to light through the probing of high-intensity x-rays at SSRL's BL6-2. The text contains part of the Method of Mechanical Theorems, one of Archimedes' most important works, which was probably copied out by a scribe in the tenth century. The parchment on which it was written was later scraped down and reused as pages in a twelfth century prayer book, producing a document known as a palimpsest (which comes from the Greek,

463

HIGH BRILLIANCE X-RAY SCATTERING FOR  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

BRILLIANCE X-RAY SCATTERING FOR BRILLIANCE X-RAY SCATTERING FOR LIFE SCIENCES (LIX) Group Leader: Lin Yang Proposal Team: O. Bilsel 1 , B. Hsiao 2 , H. Huang 3 , T. Irving 4 , A. Menzel 5 , L. Pollack 6 , C. Riekel 7 , J. Rubert 8 , H. Tsuruta 9 , L. Yang 10 1 University of Massachusetts, 2 Stony Brook University, 3 Rice University, 4 IIT, 5SLS, 6 Cornell University, 7 European Synchrotron Radiation Facility, 8 NEU, 9 Stanford Synchrotron Radiation Lightsource, 10 Brookhaven National Laboratory TECHNIQUES AND CAPABILITIES APPLICATIONS ADDITIONAL INFORMATION * Energy range 2-20keV using undulator source. Simultaneous SAXS/WAXS to cover 0.003-3Å -1 at 12keV with 1 micron spot size * Time-resolved solution scattering with resolution of (1) microseconds to milliseconds using continuous-flow mixing (5µm x 10µm spot size) and (2) milliseconds using stopped-

464

Element 104 identified by characteristic x rays  

Science Journals Connector (OSTI)

A research team at the Oak Ridge National Laboratory has recently announced that they have conclusively identified the 257 isotope of element 104. This new work shows promise of shedding light on the controversy between Albert Ghiorso and Georgi N. Flerov the leaders respectively of the groups at Lawrence Berkeley Laboratory and the Joint Institute for Nuclear Research Dubna. The isotope 104 X 257 decays by alpha emission to 102 No 253 with a half?life of 4.3 seconds. The Oak Ridge group observed the K?series x rays from nobelium in coincidence with the alpha particles from 104 X 257 ; the observation of x?ray spectra has never been reported previously by the Berkeley or Dubna workers according to Curtis E. Bemis Jr spokesman for the group.

Ronald J. Cohn

1973-01-01T23:59:59.000Z

465

X-ray radiography for container inspection  

DOE Patents [OSTI]

Arrangements of X-ray inspection systems are described for inspecting high-z materials in voluminous objects such as containers. Inspection methods may involve generating a radiographic image based on detected attenuation corresponding to a pulsed beams of radiation transmitted through a voluminous object. The pulsed beams of radiation are generated by a high-energy source and transmitted substantially downward along an incident angle, of approximately 1.degree. to 30.degree., to a vertical axis extending through the voluminous object. The generated radiographic image may be analyzed to detect on localized high attenuation representative of high-z materials and to discriminate high-z materials from lower and intermediate-z materials on the basis of the high density and greater attenuation of high-z material for higher energy (3-10 MeV) X-rays, and the compact nature of threatening masses of fissionable materials.

Katz, Jonathan I. (Clayton, MO); Morris, Christopher L. (Los Alamos, NM)

2011-06-07T23:59:59.000Z

466

Vibration diagnosis and remediation design for an x-ray optics stitching interferometer system.  

SciTech Connect (OSTI)

The Advanced Photon Source (APS) x-ray optics Metrology Laboratory currently operates a small-aperture Wyko laser interferometer in a stitching configuration. While the stitching configuration allows for easier surface characterization of long x-ray substrates and mirrors, the addition of mechanical components for optic element translation can compromise the ultimate measurement performance of the interferometer. A program of experimental vibration measurements, quantifying the laboratory vibration environment and identifying interferometer support-system behavior, has been conducted. Insight gained from the ambient vibration assessment and modal analysis has guided the development of a remediation technique. Discussion of the problem diagnosis and possible solutions are presented in this paper.

Preissner, C.; Assoufid, L.; Shu, D.; Experimental Facilities Division (APS)

2004-01-01T23:59:59.000Z

467

Sample holder for X-ray diffractometry  

DOE Patents [OSTI]

A sample holder for use with X-ray diffractometers with the capability to rotate the sample, as well as to adjust the position of the sample in the x, y, and z directions. Adjustment in the x direction is accomplished through loosening set screws, moving a platform, and retightening the set screws. Motion translators are used for adjustment in the y and z directions. An electric motor rotates the sample, and receives power from the diffractometer.

Hesch, Victor L. (Los Alamos, NM)

1992-01-01T23:59:59.000Z

468

Columbia University X-Ray Measurements  

E-Print Network [OSTI]

V-720 keV · NaI 2x2x2" detector views an energy range of 1 keV-3 MeV Store signal in the tree. computer configuration. Plasmas were created using multi-frequency ECRH, and we find that most of the plasma energy is stored in the fast electrons. The energy spectrum of the x-ray emission below 740 keV is measured

469

Silicon Absolute X-Ray Detectors  

SciTech Connect (OSTI)

The responsivity of silicon photodiodes having no loss in the entrance window, measured using synchrotron radiation in the 1.75 to 60 keV range, was compared to the responsivity calculated using the silicon thickness measured using near-infrared light. The measured and calculated responsivities agree with an average difference of 1.3%. This enables their use as absolute x-ray detectors.

Seely, John F. [Naval Research Laboratory, Washington, D.C. 20375 (United States); Korde, Raj; Sprunck, Jacob [International Radiation Detectors, Inc., Torrance, CA 90505-5243 (United States); Medjoubi, Kadda; Hustache, Stephanie [Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, BP 48, 91192 Gif-sur-Yvette CEDEX (France)

2010-06-23T23:59:59.000Z

470

X-Ray Diffraction Microscopy of Magnetic Structures  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

X-Ray Diffraction Microscopy of Magnetic Structures Print science brief icon Scientists working at ALS Beamline 12.0.2.2 have demonstrated a new x-ray technique for producing...

471