Sample records for free-electron laser xfel

  1. Numerical simulations of X-rays Free Electron Lasers (XFEL)

    E-Print Network [OSTI]

    Paolo Antonelli; Agissilaos Athanassoulis; Zhongyi Huang; Peter A. Markowich

    2014-06-17T23:59:59.000Z

    We study a nonlinear Schr\\"odinger equation which arises as an effective single particle model in X-ray Free Electron Lasers (XFEL). This equation appears as a first-principles model for the beam-matter interactions that would take place in an XFEL molecular imaging experiment in \\cite{frat1}. Since XFEL is more powerful by several orders of magnitude than more conventional lasers, the systematic investigation of many of the standard assumptions and approximations has attracted increased attention. In this model the electrons move under a rapidly oscillating electromagnetic field, and the convergence of the problem to an effective time-averaged one is examined. We use an operator splitting pseudo-spectral method to investigate numerically the behaviour of the model versus its time-averaged version in complex situations, namely the energy subcritical/mass supercritical case, and in the presence of a periodic lattice. We find the time averaged model to be an effective approximation, even close to blowup, for fast enough oscillations of the external field. This work extends previous analytical results for simpler cases \\cite{xfel1}.

  2. FREE ELECTRON LASERS

    E-Print Network [OSTI]

    Colson, W.B.

    2008-01-01T23:59:59.000Z

    1984). Colson, W. B. , "Free electron laser theory," Ph.D.aspects of the free electron laser," Laser Handbook i,Quant. Elect. Bendor Free Electron Laser Conference, Journal

  3. FREE-ELECTRON LASERS

    E-Print Network [OSTI]

    Sessler, A.M.

    2008-01-01T23:59:59.000Z

    Variable-Wiggler Free-Electron-Laser Oscillat.ion. Phys. :_.The Los Alamos Free Electron Laser: Accelerator Perfoemance.First Operation of a Free-Electron Laser. Phys . __ Rev~.

  4. Catalac free electron laser

    DOE Patents [OSTI]

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

    1982-01-01T23:59:59.000Z

    A catalac free electron laser using a rf linac (catalac) which acts as a catalyst to accelerate an electron beam in an initial pass through the catalac and decelerate the electron beam during a second pass through the catalac. During the second pass through the catalac, energy is extracted from the electron beam and transformed to energy of the accelerating fields of the catalac to increase efficiency of the device. Various embodiments disclose the use of post linacs to add electron beam energy extracted by the wiggler and the use of supplementary catalacs to extract energy at various energy peaks produced by the free electron laser wiggler to further enhance efficiency of the catalac free electron laser. The catalac free electron laser can be used in conjunction with a simple resonator, a ring resonator or as an amplifier in conjunction with a master oscillator laser.

  5. X-ray amplification from a Raman Free Electron Laser I.A. Andriyash,

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    X-ray amplification from a Raman Free Electron Laser I.A. Andriyash, E. d'Humi`eres, V 5107, F33400 Talence, France We demonstrate that a mm-scale free electron laser can operate in the X and health applications. Large scale X-ray free electron laser (XFEL) projects have been launched, and start

  6. Free-Electron Laser FLASH Injector Laser

    E-Print Network [OSTI]

    FLASH. Free-Electron Laser in Hamburg FLASH Injector Laser Laser 1 Laser 2 Next steps Siegfried | FLASH Meeting | 16-Nov-2009 FLASH. Free-Electron Laser in Hamburg Laser 1 System Overview fround trip A 541 (2005) 467­477 #12;Siegfried Schreiber | FLASH Meeting | 16-Nov-2009 FLASH. Free-Electron Laser

  7. Free electron laser

    DOE Patents [OSTI]

    Villa, Francesco (Alameda, CA)

    1990-01-01T23:59:59.000Z

    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.

  8. Circular free-electron laser

    DOE Patents [OSTI]

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

    1984-01-01T23:59:59.000Z

    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.

  9. Isochronous Beamlines for Free Electron Lasers

    E-Print Network [OSTI]

    Berz, M.

    2010-01-01T23:59:59.000Z

    for the los alamos free- electron laser. IEEE Journal of1: A schematic layout of a free electron laser. Figure 2: ABeamIines for Free Electron Lasers M. Berz July 1990

  10. Hole Coupling Resonator for Free Electron Lasers

    E-Print Network [OSTI]

    Xie, M.

    2011-01-01T23:59:59.000Z

    a Highly Stable Infrared Free Electron Laser at LBL", theseTwelfth International Free Electron Laser Conference, Paris,Coupling Resonator for Free Electron Lasers M. Xie and K. -

  11. Metal Photocathodes for Free Electron Laser Applications

    E-Print Network [OSTI]

    Greaves, Corin Michael Ricardo

    2012-01-01T23:59:59.000Z

    an Undulator of a Free Electron Laser. Electrons tra- verseand et al. “X-ray free-electron lasers”. In: Journal ofiii List of Tables iv 1 The Free Electron Laser (FEL)

  12. Rf Feedback free electron laser

    DOE Patents [OSTI]

    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

    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.

  13. 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...

  14. Femtosecond Xray Absorption Spectroscopy at a Hard Xray Free Electron Laser: Application to Spin Crossover Dynamics

    E-Print Network [OSTI]

    Ihee, Hyotcherl

    Femtosecond Xray Absorption Spectroscopy at a Hard Xray Free Electron Laser: Application to Spin Rennes 1, F35042, Rennes, France ABSTRACT: X-ray free electron lasers (XFELs) deliver short ( operated in femtosecond laser slicing mode15 ). The development of new X-ray facilities such as X-ray free

  15. FREE-ELECTRON LASERS

    E-Print Network [OSTI]

    Sessler, A.M.

    2008-01-01T23:59:59.000Z

    to the electric field of the radiation, this energy-exchangewhere the electric field of the radiation would The energydue to the electric field of the laser radiation, but in

  16. Achromatic and Isochronous Electron Beam Transport for Free Electron Lasers

    E-Print Network [OSTI]

    Bengtsson, J.

    2011-01-01T23:59:59.000Z

    Beamlines for Free Electron Lasers," LBL-28880 Preprint (Thirteenth mtemational Free Electron Laser Conference, SantaTransport for Tunable Free Electron Lasers 1. Bengtsson and

  17. Three Dimensioanl Free Electron Laser Dispersion Relation Including Betatron Oscillations

    E-Print Network [OSTI]

    Chin, Y.H.

    2011-01-01T23:59:59.000Z

    Three-Dimensional Free Electron Laser Dispersion RelationInternational Free Electron Laser Conference, Santa Fe, NM,International Free Electron Laser Conference, held in Santa

  18. Feasibility considerations of a soft-x-ray distributed feedback laser pumped by an X-FEL

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Feasibility considerations of a soft-x-ray distributed feedback laser pumped by an X-FEL Jean 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

  19. Damage threshold of inorganic solids under free-electron-laser irradiation at 32.5 nm wavelength

    E-Print Network [OSTI]

    von der Linde, D.

    to the optical components required to utilize XFEL beams, including radiation damage. Theoretical workDamage threshold of inorganic solids under free-electron-laser irradiation at 32.5 nm wavelength SC were exposed to single 25 fs long pulses of 32.5 nm free-electron-laser radiation at fluences of up

  20. Multiple pulse thermal damage thresholds of materials for x-ray free electron laser optics investigated with an ultraviolet laser

    SciTech Connect (OSTI)

    Hau-Riege, Stefan P.; London, Richard A.; Bionta, Richard M.; Soufli, Regina; Ryutov, Dmitri; Shirk, Michael; Baker, Sherry L. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94539 (United States); Smith, Patrick M.; Nataraj, Pradeep [Kovio, Inc., 1145 Sonora Court, Sunnyvale, California 94086 (United States)

    2008-11-17T23:59:59.000Z

    Optical elements to be used for x-ray free electron lasers (XFELs) must withstand multiple high-fluence pulses. We have used an ultraviolet laser to study the damage of two candidate materials, crystalline Si and B{sub 4}C-coated Si, emulating the temperature profile expected to occur in optics exposed to XFEL pulses. We found that the damage threshold for 10{sup 5} pulses is {approx}20% to 70% lower than the melting threshold.

  1. Laser Heater and seeded Free Electron Laser

    E-Print Network [OSTI]

    Dattoli, G; Sabia, E

    2014-01-01T23:59:59.000Z

    In this paper we consider the effect of laser heater on a seeded Free Electron Laser. We develop a model embedding the effect of the energy modulation induced by the heater with those due to the seeding. The present analysis is compatible with the experimental results obtained at FERMI displaying secondary maxima with increasing heater intensity. The treatment developed in the paper confirms and extends previous analyses and put in evidence further effects which can be tested in future experiments.

  2. 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...

  3. EIGENMODE ANALYSIS OF OPTICAL GUIDING IN FREE ELECTRON LASERS

    E-Print Network [OSTI]

    Xie, M.

    2010-01-01T23:59:59.000Z

    of Optical Guiding in Free Electron Lasers", Department ofGuided Mode Solutions in Free Electron Lasers", "High GainResonator in Free Electron Lasers", to be published. P.

  4. An Efficient Microwave Power Source: Free-electron Laser Afterburner

    E-Print Network [OSTI]

    Wang, C.

    2008-01-01T23:59:59.000Z

    1. Block diagram of the free-electron laser afterburner. The2. The particular free-electron laser afterburner with aMicrowave Power Source: Free-Electron Laser Afterburner c.

  5. Simulation of free-electron lasers seeded with broadband radiation

    E-Print Network [OSTI]

    Bajlekov, Svetoslav

    2012-01-01T23:59:59.000Z

    The European X-Ray Free-Electron Laser Technical DesignSimulation of free-electron lasers seeded with broadbandcoherence of free-electron laser (FEL) radiation can be

  6. The Multi-Cavity Free-Electron Laser

    E-Print Network [OSTI]

    Krishnagopal, S.

    2008-01-01T23:59:59.000Z

    The Multi-Cavity Free-Electron Laser S. Krishnagopal, G.414 The Multi-Cavity Free-Electron Laser S. Krishnagopal, G.of Multi-Cavity Free-Electron Lasers Parameters A(,um) '

  7. Resonator Modes in High Gain Free Electron Lasers

    E-Print Network [OSTI]

    Xie, M.

    2010-01-01T23:59:59.000Z

    of Optical Guiding in Free Electron Lasers", Department ofModes in High Gain Free Electron Lasers M. Xie. D.A.O.International Free Electron Laser Conference. Naples. FL.

  8. Hole-Coupled Resonators Tunable Infrared Free Electron Lasers

    E-Print Network [OSTI]

    Xie, M.

    2011-01-01T23:59:59.000Z

    International Free Electron Laser Conference, Kobe, Japan,in Mark III Free Electron Laser", These Proceedings. B.Ozcan and R.H, Pantell, "Free Electron Laser in a Confocal

  9. Resurrection of beam conditioning for free electron lasers

    E-Print Network [OSTI]

    Xie, Ming

    2003-01-01T23:59:59.000Z

    t z , Undulators and Free-Electron Lasers, (Clarendon Press,a fatal flaw in a Free Electron Laser ( F E L ) beamO N Operation of free electron lasers in shorter wavelength

  10. Free-Electron Lasers: Present Status and Future Prospects

    E-Print Network [OSTI]

    Kim, K.-J.

    2008-01-01T23:59:59.000Z

    1977). C. Brau, "Free-Electron Lasers", Science 239, 115 (T. Marshall, "Free-Electron Lasers", MacMillan (1985);C Brau, "Free- Electron Lasers", Academic Press (1990). W.B.

  11. Combination free electron and gaseous laser

    DOE Patents [OSTI]

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

    1980-01-01T23:59:59.000Z

    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.

  12. Free electron laser designs for laser amplification

    DOE Patents [OSTI]

    Prosnitz, Donald (Walnut Creek, CA); Szoke, Abraham (Fremont, CA)

    1985-01-01T23:59:59.000Z

    Method for laser beam amplification by means of free electron laser techniques. With wiggler magnetic field strength B.sub.w and wavelength .lambda..sub.w =2.pi./k.sub.w regarded as variable parameters, the method(s) impose conditions such as substantial constancy of B.sub.w /k.sub.w or k.sub.w or B.sub.w and k.sub.w (alternating), coupled with a choice of either constant resonant phase angle or programmed phase space "bucket" area.

  13. Fundamental physics at an X-ray free electron laser

    E-Print Network [OSTI]

    A. Ringwald

    2001-12-19T23:59:59.000Z

    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.

  14. Two-element free-electron lasers

    SciTech Connect (OSTI)

    Shih, C.; Yariv, A.

    1980-02-01T23:59:59.000Z

    The interaction between the electrons and the radiation in a free-electrons laser leads to a shift and a spread of the electron velocity distribution. The electron dynamics of a two-element system are studied in the small signal region. It is found that the efficiency and gain can be increased through introduction of an adjustable drift distance between two identical wigglers.

  15. Short pulse free electron laser amplifier

    DOE Patents [OSTI]

    Schlitt, Leland G. (Livermore, CA); Szoke, Abraham (Fremont, CA)

    1985-01-01T23:59:59.000Z

    Method and apparatus for amplification of a laser pulse in a free electron laser amplifier where the laser pulse duration may be a small fraction of the electron beam pulse duration used for amplification. An electron beam pulse is passed through a first wiggler magnet and a short laser pulse to be amplified is passed through the same wiggler so that only the energy of the last fraction, f, (f<1) of the electron beam pulse is consumed in amplifying the laser pulse. After suitable delay of the electron beam, the process is repeated in a second wiggler magnet, a third, . . . , where substantially the same fraction f of the remainder of the electron beam pulse is consumed in amplification of the given short laser pulse in each wiggler magnet region until the useful electron beam energy is substantially completely consumed by amplification of the laser pulse.

  16. Chaos in free electron laser oscillators

    E-Print Network [OSTI]

    C. Bruni; R. Bachelard; D. Garzella; G. L. Orlandi; M. E. Couprie

    2009-09-04T23:59:59.000Z

    The chaotic nature of a storage-ring Free Electron Laser (FEL) is investigated. The derivation of a low embedding dimension for the dynamics allows the low-dimensionality of this complex system to be observed, whereas its unpredictability is demonstrated, in some ranges of parameters, by a positive Lyapounov exponent. The route to chaos is then explored by tuning a single control parameter, and a period-doubling cascade is evidenced, as well as intermittence.

  17. Inverse free-electron laser accelerator

    SciTech Connect (OSTI)

    Pellegrini, C.; Campisi, R.

    1982-01-01T23:59:59.000Z

    We first describe the basic physical properties of an inverse free-electron laser and make an estimate of the order of magnitude of the accelerating field obtainable with such a system; then apply the general ideas to the design of an actual device and through this example we give a more accurate evaluation of the fundamental as well as the technical limitations that this acceleration scheme imposes.

  18. Free-electron laser driven by the LBNL laser-plasma accelerator

    E-Print Network [OSTI]

    Schroeder, C. B.

    2010-01-01T23:59:59.000Z

    Free-electron laser driven by the LBNL laser-plasmaA design of a compact free-electron laser (FEL), generatingare considered. Keywords: Free-electron laser, laser-plasma

  19. Transverse Coherence of a VUV Free Electron Laser

    E-Print Network [OSTI]

    Transverse Coherence of a VUV Free Electron Laser Dissertation zur Erlangung des Doktorgrades des The transverse coherence is of paramount importance for many applications of a free electron laser (FEL). In this thesis, the first direct measurement of the transverse coherence of a free electron laser at vacuum

  20. A PLASMA CHANNEL BEAM CONDITIONER FOR A FREE ELECTRON LASER

    E-Print Network [OSTI]

    Wurtele, Jonathan

    A PLASMA CHANNEL BEAM CONDITIONER FOR A FREE ELECTRON LASER G. Penn , A.M. Sessler, J.S. Wurtele of free electron lasers (FELs) can be dramatically improved. Under certain con- ditions, the FEL can transverse action and energy, has been shown to be advantageous for free electron laser (FEL) performance [1

  1. Macro-temporal structure of storage ring free electron lasers

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    997 Macro-temporal structure of storage ring free electron lasers P. Elleaume Département de laser. Abstract. 2014 I derive simple dimensionless equations governing the storage ring free electron Ring Free Electron Laser (1) (S.R.L.), the S.R.L. was thought to be pseudo-continuous except for some

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

    E-Print Network [OSTI]

    Staples, John

    2009-01-01T23:59:59.000Z

    Zholents, K. Holdack, Free Electron Laser Conference, FEL06,26th International Free Electron Laser Conference, Trieste,27th International Free Electron Laser Conference, Stanford,

  3. Design of a free-electron laser driven by the LBNL laser-plasma-accelerator

    E-Print Network [OSTI]

    2008-01-01T23:59:59.000Z

    of the visible free- electron laser oscillator experiment”,based VUV and X-ray free electron lasers”, Appl. Phys. BDesign of a free-electron laser driven by the LBNL laser-

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

    E-Print Network [OSTI]

    André, Jean-Michel; Jonnard, Philippe

    2014-01-01T23:59:59.000Z

    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.

  5. An inverse free electron laser accelerator experiment

    SciTech Connect (OSTI)

    Wernick, I.; Marshall, T.C.

    1992-01-01T23:59:59.000Z

    A free electron laser was configured as an autoaccelerator to test the principle of accelerating electrons by stimulated absorption of radiation ([lambda] = 1.65mm) by an electron beam (750kV) traversing an undulator. Radiation is produced in the first section of a constant period undulator (1[sub w1] = 1.43cm) and then absorbed ([approximately] 40%) in a second undulator, having a tapered period (1[sub w2] = 1.8 [minus] 2.25cm), which results in the acceleration of a subgroup ([approximately] 9%) of electrons to [approximately] 1MeV.

  6. An inverse free electron laser accelerator experiment

    SciTech Connect (OSTI)

    Wernick, I.; Marshall, T.C.

    1992-12-31T23:59:59.000Z

    A free electron laser was configured as an autoaccelerator to test the principle of accelerating electrons by stimulated absorption of radiation ({lambda} = 1.65mm) by an electron beam (750kV) traversing an undulator. Radiation is produced in the first section of a constant period undulator (1{sub w1} = 1.43cm) and then absorbed ({approximately} 40%) in a second undulator, having a tapered period (1{sub w2} = 1.8 {minus} 2.25cm), which results in the acceleration of a subgroup ({approximately} 9%) of electrons to {approximately} 1MeV.

  7. Free Electron Lasers using `Beam by Design'

    E-Print Network [OSTI]

    Henderson, J R; McNeil, B W J

    2015-01-01T23:59:59.000Z

    Several methods have been proposed in the literature to improve Free Electron Laser output by transforming the electron phase-space before entering the FEL interaction region. By utilising `beam by design' with novel undulators and other beam changing elements, the operating capability of FELs may be further usefully extended. This paper introduces two new such methods to improve output from electron pulses with large energy spreads and the results of simulations of these methods in the 1D limit are presented. Both methods predict orders of magnitude improvements to output radiation powers.

  8. Free electron laser with masked chicane

    DOE Patents [OSTI]

    Nguyen, Dinh C. (Los Alamos, NM); Carlsten, Bruce E. (Los Alamos, NM)

    1999-01-01T23:59:59.000Z

    A free electron laser (FEL) is provided with an accelerator for outputting electron beam pulses; a buncher for modulating each one of the electron beam pulses to form each pulse into longitudinally dispersed bunches of electrons; and a wiggler for generating coherent light from the longitudinally dispersed bunches of electrons. The electron beam buncher is a chicane having a mask for physically modulating the electron beam pulses to form a series of electron beam bunches for input to the wiggler. In a preferred embodiment, the mask is located in the chicane at a position where each electron beam pulse has a maximum dispersion.

  9. Airborne Tactical Free-Electron Laser

    SciTech Connect (OSTI)

    Roy Whitney; George Neil

    2007-02-01T23:59:59.000Z

    The goal of 100 kilowatts (kW) of directed energy from an airborne tactical platform has proved challenging due to the size and weight of most of the options that have been considered. However, recent advances in Free-Electron Lasers appear to offer a solution along with significant tactical advantages: a nearly unlimited magazine, time structures for periods from milliseconds to hours, radar like functionality, and the choice of the wavelength of light that best meets mission requirements. For an Airborne Tactical Free-Electron Laser (ATFEL) on a platforms such as a Lockheed C-130J-30 and airships, the two most challenging requirements, weight and size, can be met by generating the light at a higher harmonic, aggressively managing magnet weights, managing cryogenic heat loads using recent SRF R&D results, and using FEL super compact design concepts that greatly reduce the number of components. The initial R&D roadmap for achieving an ATFEL is provided in this paper. Performing this R&D is expected to further reduce the weight, size and power requirements for the FELs the Navy is currently developing for shipboard applications, as well as providing performance enhancements for the strategic airborne MW class FELs. The 100 kW ATFEL with its tactical advantages may prove sufficiently attractive for early advancement in the queue of deployed FELs.

  10. Analogy between free electron laser and channeling by crystal planes

    E-Print Network [OSTI]

    X. Artru

    2005-03-21T23:59:59.000Z

    The trapping of electrons in the ponderomotive potential wells, which governs a free electron laser or inverse free electron laser at high gain, is analogous to the channeling of charged particles by atomic planes of a crystal. A bent crystal is analogous to a period-tapered free electron laser. This analogy is different from the well-known one between channeling and undulator radiations.

  11. Diffraction Properties of Periodic Lattices under Free Electron Laser Radiation

    SciTech Connect (OSTI)

    Rajkovic, I.; Busse, G.; Hallmann, J.; More, R.; Petri, M.; Quevedo, W. [Max Planck Institute for Biophysical Chemistry, 37070 Goettingen (Germany); Krasniqi, F.; Rudenko, A. [Max-Planck Advanced Study Group at CFEL, Notkestrasse 85, 22607 Hamburg (Germany); Tschentscher, T. [European XFEL GmbH, Albert-Einstein-Ring 19, 22671 Hamburg (Germany); Stojanovic, N.; Duesterer, S.; Treusch, R. [HASYLAB at DESY, Notkestrasse 85, 22607 Hamburg (Germany); Tolkiehn, M. [Institut fuer Roentgenphysik, Universitaet Goettingen, Friedrich-Hund-Platz 1, 37077 Goettingen (Germany); Techert, S. [Max Planck Institute for Biophysical Chemistry, 37070 Goettingen (Germany); Max-Planck Advanced Study Group at CFEL, Notkestrasse 85, 22607 Hamburg (Germany)

    2010-03-26T23:59:59.000Z

    In this Letter, we report the pioneering use of free electron laser radiation for the investigation of periodic crystalline structures. The diffraction properties of silver behenate single nanocrystals (5.8 nm periodicity) with the dimensions of 20 nmx20 nmx20 {mu}m and as powder with grain sizes smaller than 200 nm were investigated with 8 nm free electron laser radiation in single-shot modus with 30 fs long free electron laser pulses. This work emphasizes the possibility of using soft x-ray free electron laser radiation for these crystallographic studies on a nanometer scale.

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

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

    the collaboration's FEL experiment (image not actual size). Jefferson Lab's Free-Electron Laser explores promise of carbon nanotubes By James Schultz January 27, 2003...

  13. High Gradient Inverse Free Electron Laser (IFEL) Accelerator

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

    Gradient High energy gain Inverse Free Electron Laser P. Musumeci UCLA Department of Physics and Astronomy On Behalf of the RUBICON collaboration ATF user meeting, BNL, October 6...

  14. Rippled beam free electron laser amplifier

    DOE Patents [OSTI]

    Carlsten, Bruce E. (Los Alamos, NM)

    1999-01-01T23:59:59.000Z

    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.

  15. TEMPERATURE MEASUREMENT SYSTEM OF NOVOSIBIRSK FREE ELECTRON LASER

    E-Print Network [OSTI]

    Kozak, Victor R.

    TEMPERATURE MEASUREMENT SYSTEM OF NOVOSIBIRSK FREE ELECTRON LASER B.A.Gudkov, P.A.Selivanov, V all sensors are recorded to the database every 30 seconds. INTRODUCTION A high-power free electron laser (FEL), based on the microtron-recuperator[1], is under construction now at Budker Institute

  16. Ignition feedback regenerative free electron laser (FEL) amplifier

    DOE Patents [OSTI]

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

    2001-01-01T23:59:59.000Z

    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.

  17. High-intensity double-pulse X-ray free-electron laser

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

    Marinelli, A.; Ratner, D.; Lutman, A. A.; Turner, J.; Welch, J.; Decker, F. -J.; Loos, H.; Behrens, C.; Gilevich, S.; Miahnahri, A. A.; et al

    2015-03-06T23:59:59.000Z

    The X-ray free-electron laser has opened a new era for photon science, improving the X-ray brightness by ten orders of magnitude over previously available sources. Similar to an optical laser, the spectral and temporal structure of the radiation pulses can be tailored to the specific needs of many experiments by accurately manipulating the lasing medium, that is, the electron beam. Here we report the generation of mJ-level two-colour hard X-ray pulses of few femtoseconds duration with an XFEL driven by twin electron bunches at the Linac Coherent Light Source. This performance represents an improvement of over an order of magnitudemore »in peak power over state-of-the-art two-colour XFELs. The unprecedented intensity and temporal coherence of this new two-colour X-ray free-electron laser enable an entirely new set of scientific applications, ranging from X-ray pump/X-ray probe experiments to the imaging of complex biological samples with multiple wavelength anomalous dispersion.« less

  18. Laser Phase Errors in Seeded Free Electron Lasers

    SciTech Connect (OSTI)

    Ratner, D.; Fry, A.; Stupakov, G.; White, W.; /SLAC

    2012-04-17T23:59:59.000Z

    Harmonic seeding of free electron lasers has attracted significant attention as a method for producing transform-limited pulses in the soft x-ray region. Harmonic multiplication schemes extend seeding to shorter wavelengths, but also amplify the spectral phase errors of the initial seed laser, and may degrade the pulse quality and impede production of transform-limited pulses. In this paper we consider the effect of seed laser phase errors in high gain harmonic generation and echo-enabled harmonic generation. We use simulations to confirm analytical results for the case of linearly chirped seed lasers, and extend the results for arbitrary seed laser envelope and phase.

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

    E-Print Network [OSTI]

    Baptiste, Kenneth

    2009-01-01T23:59:59.000Z

    The Bessy Soft X-Ray Free Electron Laser, ISBN 3-9809534-0-26th International Free Electron Laser Conference, Trieste,Proceedings of 21st Free-Electron Laser Conference (FEL’99),

  20. Exact and variational solutions of 3D Eigenmodes in high gain Free Electron Lasers

    E-Print Network [OSTI]

    Xie, M.

    2011-01-01T23:59:59.000Z

    Motz, Undulators and Free-Electron Lasers, (Clarendon Press,in High . Gain Free Electron Lasers MingXie Accelerator andin High Gain Free Electron Lasers Ming Xie Accelerator and

  1. Physically Transparent Formulation of a Free-Electron Laser in the Linear Gain Regime

    E-Print Network [OSTI]

    Barletta, W.A.

    2008-01-01T23:59:59.000Z

    in High-Gain, High-Power Free-Electron Lasers: Physics andFormulation of a Free-Electron Laser in the Linear GainFormulation of a Free-Electron Laser in the Linear Gain

  2. Design Overview of a Highly Stable Infrared Free Electron Laser at LBL

    E-Print Network [OSTI]

    Kim, K.-J.

    2011-01-01T23:59:59.000Z

    Twelfth International Free Electron Laser Conference, Paris,Stable Infrared Free Electron Laser at LBL K. -J. Kim, M.Stable Infrared Free Electron Laser at LBL* K. -J. Kim, M.

  3. Standing-Wave Free-Electron Laser Two-Beam Accelerator

    E-Print Network [OSTI]

    Sessler, Andrew M.

    2008-01-01T23:59:59.000Z

    the 11th International Free-Electron Laser Conference, Nuc!.A Standing-Wave Free-Electron Laser Two-Beam Accelerator30418 Standing-Wave Free-Electron Laser Two-Beam Accelerator

  4. Sensitivity Studies of a Standing-Wave Free-Electron Laser

    E-Print Network [OSTI]

    Rangarahan, G.

    2008-01-01T23:59:59.000Z

    Proc. 12th Int. Free Electron Laser Conf. , Nuel. Instr. andof a Standing-Wave Free-Electron Laser G. Rangarajan and A.of a Standing-Wave Free-Electron Laser Govindan Rangarajan

  5. THE FREE ELECTRON LASER AS A POWER SOURCE FOR A HIGH-GRADIENT ACCELERATING STRUCTURE

    E-Print Network [OSTI]

    Sessler, A.M.

    2008-01-01T23:59:59.000Z

    18-23, 1982 THE FREE ELECTRON LASER AS A POWER SOURCE FOR AAC03-76SF00098 THE FREE ELECTRON LASER AS A POWER SOURCE FORVariable Parameter Free Electron Laser", to be pub 1 i shed

  6. The Evolution and Limits of Spectral Bandwidth in Free Electron Lasers

    E-Print Network [OSTI]

    Kim, K.-J.

    2010-01-01T23:59:59.000Z

    Spectral Bandwidth in Free Electron Lasers". In the sentenceBandwidth in Free Electron Lasers K. -J. Kim November 1990of Spectral Bandwidth in Free Electron Lasers* Kwang-Je Kim

  7. A NEW VERSION OF A FREE ELECTRON LASER TWO BEAM ACCELERATOR

    E-Print Network [OSTI]

    Sessler, A.M.

    2008-01-01T23:59:59.000Z

    Radiation in Free Electron Laser Two-Beam Accelerator",Power 35 GHz Testing of a Free-Electron Laser and Two-BeamA New Version of a Free Electron Laser Two-Beam Accelerator

  8. Discrete Cavity Model of a Standing-Wave Free-Electron Laser

    E-Print Network [OSTI]

    Rangarajan, G.

    2008-01-01T23:59:59.000Z

    Presented at the 1991 Free Electron Laser Conference, Santaof a Standing-Wave Free-Electron Laser G. Rangarajan, A.of a Standing-Wave Free-Electron Laser Govindan Rangarajan

  9. The Evolution and Limits of Spectral Bandwidth in Free Electron Lasers

    E-Print Network [OSTI]

    Kim, K.-J.

    2011-01-01T23:59:59.000Z

    Spectral Bandwidth in Free Electron Lasers". In the sentenceBandwidth in Free Electron Lasers K. -J. Kim November 1990of Spectral Bandwidth in Free Electron Lasers* Kwang-Je Kim

  10. Sensitivity of nonlinear harmonic generation to electron beam quality in free-electron lasers

    E-Print Network [OSTI]

    2002-01-01T23:59:59.000Z

    Jr. , Principles of Free-electron Lasers (Chapman & Hall,experiment," in Free Electron Laser Challenges II, Harold E.Beam Quality in Free-Electron Lasers* Sandra G . Biedron*f,

  11. Macroparticle Theory of a Standing Wave Free-Electron Laser Two-Beam Accelerator

    E-Print Network [OSTI]

    Takayama, K.

    2008-01-01T23:59:59.000Z

    Motz, Undulators and Free-Electron Laser (Clarendon Press,of a Standing Wave Free-Electron Laser Two-Beam Acceleratorof a Standing Wave Free-Electron Laser Two-Beam Accelerator

  12. FREE ELECTRON LASERS FOR THE PRODUCTION OF INFRARED AND MILLIMETER WAVES

    E-Print Network [OSTI]

    Sessler, A.M.

    2008-01-01T23:59:59.000Z

    Hughes Low-Voltage Free-Electron Laser Program," in Proc.of the 1985 Free Electron Laser Conference, Lake Tahoe,Mark III Infrared Free-Electron Laser," in Proc. of the 1985

  13. OPTIMIZATION OF THE PARAMETERS OF A STORAGE RING FOR A HIGH POWER XUV FREE ELECTRON LASER

    E-Print Network [OSTI]

    Jackson, A.

    2010-01-01T23:59:59.000Z

    A.M. Sessler. 'free Electron Laser . LBL -l 8905 (JanuaryFOR A HIGH POWER XUV FREE ELECTRON LASER. A. Jackson, J.for a High Power XUV Free Electron Laser," (LBL'19771, June,

  14. Stability of Resonator Configurations in the Presence of Free-Electron Laser Interactions

    E-Print Network [OSTI]

    Krishnagopal, S.

    2008-01-01T23:59:59.000Z

    and R.H.Pantell, 'The Free-Electron Laser In A ConfocalInternational Free-Electron Laser Conference, Kobe, Japan,in the Presence of Free-Electron Laser Interactions S.

  15. Obtaining attosecond X-ray pulses using a self-amplified spontaneous emission free electron laser

    E-Print Network [OSTI]

    Zholents, A.A.; Penn, G.

    2005-01-01T23:59:59.000Z

    Handbook, Vol- ume 6: Free Electron Lasers (North-Holland,spontaneous emission free electron laser A.A. Zholents, G.spontaneous emission free electron laser A. A. Zholents and

  16. Phase stability of a standing-wave free-electron laser

    E-Print Network [OSTI]

    Sharp, W.M.

    2008-01-01T23:59:59.000Z

    of a Standing-Wave Free-Electron Laser", proceeding of theCoupled-Cavity Free- Electron Laser Two-Beam Accelerator",of a Standing-Wave Free-Electron Laser W. M. Sharp Lawrence

  17. Terawatt x-ray free-electron-laser optimization by transverse electron distribution shaping

    E-Print Network [OSTI]

    Emma, C; Wu, J; Fang, K; Chen, S; Serkez, S; Pellegrini, C

    2014-01-01T23:59:59.000Z

    33rd International Free Electron Laser Conference, Shanghai,TERAWATT X-RAY FREE-ELECTRON-LASER … Phys. Rev. ST Accel.23rd International Free Electron Laser Conference and 8th

  18. Accelerator Design Study for a Soft X-Ray Free Electron Laser at the Lawrence Berkeley National Laboratory

    E-Print Network [OSTI]

    Kur, E.

    2010-01-01T23:59:59.000Z

    and Experiment”, Free Electron Laser Conference, FEL06,from Shot-Noise, Free Electron Laser Conference FEL08for FERMI@elettra, Free Electron Laser Conference FEL07

  19. Longitudinally Coherent Single-Spike Radiation from a Self-Amplified Spontaneous Emission Free-Electron Laser

    E-Print Network [OSTI]

    Marcus, Gabriel Andrew

    2012-01-01T23:59:59.000Z

    of Free Electron Laser Operation . . . . . . . . . Undulatorfitting formula for free-electron lasers with strong space-modes in high-gain free-electron lasers,” Phys. Rev. ST

  20. Boiling the Vacuum with an X-Ray Free Electron Laser

    E-Print Network [OSTI]

    A. Ringwald

    2003-04-15T23:59:59.000Z

    X-ray free electron lasers will be constructed in this decade, both at SLAC in the form of the so-called Linac Coherent Light Source as well as at DESY, where the so-called TESLA XFEL laboratory uses techniques developed for the design of the TeV energy superconducting electron-positron linear accelerator TESLA. Such X-ray lasers may allow also for high-field science applications by exploiting the possibility to focus their beams to a spot with a small radius, hopefully in the range of the laser wavelength. Along this route one obtains very large electric fields, much larger than those obtainable with any optical laser of the same power. We consider here the possibility of obtaining an electric field so high that electron-positron pairs are spontaneously produced in vacuum (Schwinger pair production) and review the prospects to verify this non-perturbative production mechanism for the first time in the laboratory.

  1. Wiggler plane focusing in a linear free electron laser

    DOE Patents [OSTI]

    Scharlemann, Ernst T. (Livermore, CA)

    1988-01-01T23:59:59.000Z

    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.

  2. Free electron laser using Rf coupled accelerating and decelerating structures

    DOE Patents [OSTI]

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

    1984-01-01T23:59:59.000Z

    A free electron laser and free electron laser amplifier using beam transport devices for guiding an electron beam to a wiggler of a free electron laser and returning the electron beam to decelerating cavities disposed adjacent to the accelerating cavities of the free electron laser. Rf energy is generated from the energy depleted electron beam after it emerges from the wiggler by means of the decelerating cavities which are closely coupled to the accelerating cavities, or by means of a second bore within a single set of cavities. Rf energy generated from the decelerated electron beam is used to supplement energy provided by an external source, such as a klystron, to thereby enhance overall efficiency of the system.

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

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

    the Navy's goals and expectations and we expect no less from the upgraded FEL." The Free-Electron Laser upgrade project is funded by the Department of Defense's Office of...

  4. Microsoft PowerPoint - High Gradient Inverse Free Electron Laser...

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

    Hi h G di t Hi h i High Gradient High energy gain Inverse Free Electron Laser at BNL P. Musumeci UCLA Department of Physics and Astronomy ATF user meeting April 2-3 2009 Outline...

  5. Single electron beam rf feedback free electron laser

    DOE Patents [OSTI]

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

    1981-02-11T23:59:59.000Z

    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.

  6. Quantum effects with an X-ray free electron laser

    E-Print Network [OSTI]

    C. D. Roberts; S. M. Schmidt; D. V. Vinnik

    2002-06-03T23:59:59.000Z

    A quantum kinetic equation coupled with Maxwell's equation is used to estimate the laser power required at an XFEL facility to expose intrinsically quantum effects in the process of QED vacuum decay via spontaneous pair production. A 9 TW-peak XFEL laser with photon energy 8.3 keV could be sufficient to initiate particle accumulation and the consequent formation of a plasma of spontaneously produced pairs. The evolution of the particle number in the plasma will exhibit non-Markovian aspects of the strong-field pair production process and the plasma's internal currents will generate an electric field whose interference with that of the laser leads to plasma oscillations.

  7. Results of the free electron laser oscillation experiments on the ACO storage ring

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    989 Results of the free electron laser oscillation experiments on the ACO storage ring P. Elleaume. Abstract. 2014 A storage ring free-electron laser oscillator has been operated above threshold at a visible] or from a free electron laser. The free electron laser (F.E.L.) is a very promising source of coherent

  8. democrite-00023911,version1-18Mar2005 Analogy between free electron laser

    E-Print Network [OSTI]

    Boyer, Edmond

    democrite-00023911,version1-18Mar2005 Analogy between free electron laser and channeling by crystal, which governs a free electron laser or inverse free electron laser at high gain, is analogous-tapered free electron laser. This analogy is different from the well-known one between channeling and undulator

  9. Resonator design for a visible wavelength free-electron laser (*)

    SciTech Connect (OSTI)

    Bhowmik, A.; Lordi, N. (Rockwell International Corp., Canoga Park, CA (United States). Rocketdyne Div.); Ben-Zvi, I.; Gallardo, J. (Brookhaven National Lab., Upton, NY (United States))

    1990-01-01T23:59:59.000Z

    Design requirements for a visible wavelength free-electron laser being developed at the Accelerator Test Facility at Brookhaven National Laboratory are presented along with predictions of laser performance from 3-D numerical simulations. The design and construction of the optical resonator, its alignment and control systems are also described. 15 refs., 8 figs., 4 tabs.

  10. Two-dimensional optimization of free-electron-laser designs

    DOE Patents [OSTI]

    Prosnitz, D.; Haas, R.A.

    1982-05-04T23:59:59.000Z

    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.

  11. Two-dimensional optimization of free electron laser designs

    DOE Patents [OSTI]

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

    1985-01-01T23:59:59.000Z

    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.

  12. Damage threshold of inorganic solids under free-electron-laser irradiation at 32.5 nm wavelength

    SciTech Connect (OSTI)

    Hau-Riege, S; London, R A; Bionta, R M; McKernan, M A; Baker, S L; Krzywinski, J; Sobierajski, R; Nietubyc, R; Pelka, J B; Jurek, M; Klinger, D; Juha, L; Chalupsky, J; Cihelka, J; Hajkova, V; Koptyaev, S; Velyhan, A; Krasa, J; Kuba, J; Tiedtke, K; Toleikis, S; Tschentscher, T; Wabnitz, H; Bergh, M; Caleman, C; Sokolowski-Tinten, K; Stojanovic, N; Zastrau, U; Tronnier, A; Meyer-ter-Vehn, J

    2007-12-03T23:59:59.000Z

    We exposed samples of B4C, amorphous C, chemical-vapor-deposition (CVD)-diamond C, Si, and SiC to single 25 fs-long pulses of 32.5 nm free-electron-laser radiation at fluences of up to 2.2 J/cm{sup 2}. The samples were chosen as candidate materials for x-ray free electron laser (XFEL) optics. We found that the threshold for surface-damage is on the order of the fluence required for thermal melting. For larger fluences, the crater depths correspond to temperatures on the order of the critical temperature, suggesting that the craters are formed by two-phase vaporization [1]. XFELs have the promise of producing extremely high-intensity ultrashort pulses of coherent, monochromatic radiation in the 1 to 10 keV regime. The expected high output fluence and short pulse duration pose significant challenges to the optical components, including radiation damage. It has not been possible to obtain direct experimental verification of the expected damage thresholds since appropriate x-ray sources are not yet available. FLASH has allowed us to study the interaction of high-fluence short-duration photon pulses with materials at the shortest wavelength possible to date. With these experiments, we have come closer to the extreme conditions expected in XFEL-matter interaction scenarios than previously possible.

  13. Nuclear Instruments and Methods in Physics Research A 483 (2002) 482487 Anomalous free electron laser interaction

    E-Print Network [OSTI]

    Jerby, Eli

    2002-01-01T23:59:59.000Z

    Road, Ramat Aviv 69978, Israel Abstract Free electron lasers (FELs) are considered, typically, as fast: 41.60 Cr Keywords: Free electron laser 1. Introduction Free electron lasers (FELs) and cyclotronNuclear Instruments and Methods in Physics Research A 483 (2002) 482­487 Anomalous free electron

  14. Multifrequency, single pass free electron laser

    DOE Patents [OSTI]

    Szoke, Abraham (Fremont, CA); Prosnitz, Donald (Walnut Creek, CA)

    1985-01-01T23:59:59.000Z

    A method for simultaneous amplification of laser beams with a sequence of frequencies in a single pass, using a relativistic beam of electrons grouped in a sequence of energies corresponding to the sequence of laser beam frequencies. The method allows electrons to pass from one potential well or "bucket" to another adjacent bucket, thus increasing efficiency of trapping and energy conversion.

  15. Metal Photocathodes for Free Electron Laser Applications

    E-Print Network [OSTI]

    Greaves, Corin Michael Ricardo

    2012-01-01T23:59:59.000Z

    uSXRD orientation map of the LCLS Photocathode. The field ofimage of the center of the LCLS photocathode. The horizontalsize of the laser spot in LCLS. The image was taken with a

  16. Wiggler plane focusing in a linear free electron laser

    DOE Patents [OSTI]

    Scharlemann, E.T.

    1985-11-21T23:59:59.000Z

    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.

  17. Wiggler plane focusing in a linear free electron laser

    DOE Patents [OSTI]

    Scharlemann, E.T.

    1988-02-23T23:59:59.000Z

    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. 5 figs.

  18. Microscopic linear liquid streams in vacuum: Injection of solvated biological samples into X-ray free electron lasers

    SciTech Connect (OSTI)

    Doak, R. B.; DePonte, D. P.; Nelson, G.; Camacho-Alanis, F.; Ros, A.; Spence, J. C. H.; Weierstall, U. [Arizona State University, Tempe, AZ 85287-1504 (United States); Centre for Free-Electron Laser Science, DESY, D-22607 Hamburg (Germany); Arizona State University, Tempe, AZ 85287-1504 (United States)

    2012-11-27T23:59:59.000Z

    Microscopic linear liquid free-streams offer a means of gently delivering biological samples into a probe beam in vacuum while maintaining the sample species in a fully solvated state. By employing gas dynamic forces to form the microscopic liquid stream (as opposed to a conventional solid-walled convergent nozzle), liquid free-streams down to 300 nm diameter have been generated. Such 'Gas Dynamic Virtual Nozzles' (GDVN) are ideally suited to injecting complex biological species into an X-ray Free Electron Laser (XFEL) to determine the structure of the biological species via Serial Femtosecond Crystallography (SFX). GDVN injector technology developed for this purpose is described.

  19. Simulation of free-electron lasers seeded with broadband radiation

    SciTech Connect (OSTI)

    Bajlekov, Svetoslav; Fawley, William; Schroeder, Carl; Bartolini, Riccardo; Hooker, Simon

    2011-03-10T23:59:59.000Z

    The longitudinal coherence of free-electron laser (FEL) radiation can be enhanced by seeding the FEL with high harmonics of an optical laser pulse. The radiation produced by high-harmonic generation (HHG), however, has a fast-varying temporal profile that can violate the slowly varying envelope approximation and limited frequency window that is employed in conventional free-electron laser simulation codes. Here we investigate the implications of violating this approximation on the accuracy of simulations. On the basis of both analytical considerations and 1D numerical studies, it is concluded that, for most realistic scenarios, conventional FEL codes are capable of accurately simulating the FEL process even when the seed radiation violates the slowly varying envelope approximation. We additionally discuss the significance of filtering the harmonic content of broadband HHG seeds.

  20. Inverse free electron laser accelerator for advanced light sources

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

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

    2012-06-01T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Loss, Daniel

    LETTERS Injection of harmonics generated in gas in a free-electron laser providing intense lasers promise to extend this down to femtosecond timescales. The process by which free-electron lasers of the free-electron laser saturation length, and the generation of nonlinear harmonics13 at 54 nm and 32 nm

  2. Broadband photoacoustic spectroscopy using a free-electron laser J. Gomez Rivasa)

    E-Print Network [OSTI]

    Sprik, Rudolf

    Broadband photoacoustic spectroscopy using a free-electron laser J. Go´mez Rivasa) and R. Sprikb generated by a free-electron laser, we demonstrate the capabilities of this sort of laser to perform demonstrate that the pulsed structure of a free-electron laser FEL might be used for sensitive PA spectroscopy

  3. Microstructure-based laser-driven free-electron laser T. Plettner , R.L. Byer

    E-Print Network [OSTI]

    Byer, Robert L.

    Microstructure-based laser-driven free-electron laser T. Plettner Ã, R.L. Byer E.L. Ginzton-synchronous with the electron beam. This allows for an undulator period that is much greater than the laser wavelength. Due and therefore lead to a very compact free-electron-based radiation device. & 2008 Elsevier B.V. All rights

  4. FREE ELECTRON LASER FOR SIBERIAN CENTRE FOR PHOTOCHEMICAL RESEARCH: THE CONTROL SYSTEM FOR THE

    E-Print Network [OSTI]

    Kozak, Victor R.

    FREE ELECTRON LASER FOR SIBERIAN CENTRE FOR PHOTOCHEMICAL RESEARCH: THE CONTROL SYSTEM of the Siberian Branch of RAS. Abstract. A control system for the magnetic system of the free electron laser (FEL

  5. 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...

  6. Design of a free-electron laser driven by the LBNL laser-plasma-accelerator

    E-Print Network [OSTI]

    2008-01-01T23:59:59.000Z

    free-electron laser (FEL), generating ultra-fast, high-drive laser pulse, enabling pump-probe studies in ultra-fastto the laser driver, making such a source ideal for ultra-

  7. Chirped pulse inverse free-electron laser vacuum accelerator

    DOE Patents [OSTI]

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

    2002-01-01T23:59:59.000Z

    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.

  8. Fifth-Generation Free-Electron Laser Light Sources

    SciTech Connect (OSTI)

    Pellegrini, Claudio (UCLA) [UCLA

    2011-03-02T23:59:59.000Z

    During the past few years, the Linac Coherent Light Source (LCLS) and the Free-Electron Laser in Hamburg (FLASH) have demonstrated the outstanding capability of free-electron lasers (FELs) as sources of coherent radiation in the soft and hard x-ray region. The high intensity, tens of GW, short pulses (few to less than 100 femtoseconds, and the unique transverse coherence properties are opening a new window to study the structure and dynamics of atomic and molecular systems. The LCLS, FLASH, and the other FELs now under construction are only the beginning of the development of these light sources. The next generations will reach new levels of performance: terawatt, atto-second, ultra-small line-width, high repetition rate, full longitudinal and transverse coherence. These future developments and the R&D needed to successfully build and operate the next generation of FEL light sources will be discussed.

  9. Frequency shifting in free-electron lasers G. Shvets and J. S. Wurtele

    E-Print Network [OSTI]

    Wurtele, Jonathan

    Frequency shifting in free-electron lasers G. Shvets and J. S. Wurtele Plasma Fusion Center 1993; accepted 30 September 1993) Frequency shifting in free-electron laser (FEL) oscillators investigation. Free- electron laser sources have been proposed' with an ex- tremely tight requirement

  10. Title of Document: EMITTANCE MEASUREMENTS OF THE JEFFERSON LAB FREE ELECTRON LASER

    E-Print Network [OSTI]

    Anlage, Steven

    ABSTRACT Title of Document: EMITTANCE MEASUREMENTS OF THE JEFFERSON LAB FREE ELECTRON LASER USING, such as the ones that power Free Electron Lasers (FEL), require high quality (low emittance) beams for efficient to Free Electron Lasers............................................ 4 1.2.1 Basic Principles of an FEL

  11. THE VUV FREE ELECTRON LASER BASED ON THE TESLA TEST FACILITY AT DESY

    E-Print Network [OSTI]

    THE VUV FREE ELECTRON LASER BASED ON THE TESLA TEST FACILITY AT DESY J. Rossbach, for the TESLA FEL Collaboration Deutsches Elektronen-Synchrotron, DESY, 22603 Hamburg , Germany Abstract A Free-Electron Laser exceptionally well suited for a short-wavelength Free-Electron Laser: Excellent beam quality, mandatory

  12. Bart Faatz | FLASH Seminar | 9-Nov-2010 Free-Electron Laser

    E-Print Network [OSTI]

    Bart Faatz | FLASH Seminar | 9-Nov-2010 FLASH. Free-Electron Laser in Hamburg Lasing at 4.x nm »First at 4.45 »First at 4.6 »First at 4.12 #12;FLASH. Free-Electron Laser in Hamburg FLASH SASE-2010 FLASH. Free-Electron Laser in Hamburg The new FLASH layout 315 m Bunch Compressor Bypass

  13. Competing instabilities in the circular free-electron laser Yasushi Kawai and Hirobumi Saito

    E-Print Network [OSTI]

    Wurtele, Jonathan

    Competing instabilities in the circular free-electron laser Yasushi Kawai and Hirobumi Saito free-electron laser (FEL) is developed. A matrix dispersion relation, which includes coupling between of the amplitudes of TE and TM modes are presented. I. INTRODUCTION The free-electron laser (FEL) has the potential

  14. SHORT-WAVELENGTH, SINGLE-PASS FREE-ELECTRON LASERS J. Rossbach, DESY, 22603 Hamburg, Germany

    E-Print Network [OSTI]

    SHORT-WAVELENGTH, SINGLE-PASS FREE-ELECTRON LASERS J. Rossbach, DESY, 22603 Hamburg, Germany in demonstration of high power gain at single- pass free-electron lasers operating in the wavelength range from in the undulator. Eq. (1) exhibits two main advantages of the free-electron laser: the free tunability

  15. Theoretical Examination of Transfer Cavities in a Standing-wave Free-electron Laser Two-beam Accelerator

    E-Print Network [OSTI]

    Govil, R.

    2008-01-01T23:59:59.000Z

    Standing-Wave Free-Electron Laser Two-Beam Accelerator",the Standing-Wave Free-Electron Laser Two-Beam Accelerator",A.M. Sessler, "The Free-Electron Laser as a Power Source for

  16. Common Analysis of the Relativistic Klystron and the Standing-Wave Free-Electron Laser Two-Beam Accelerator

    E-Print Network [OSTI]

    Wurtele, Jonathan S.

    2008-01-01T23:59:59.000Z

    of the standing-wave free-electron laser on the same footingSessler, A.M. , "The Free Electron Laser as a Power SourceNew Version of a Free Electron Laser Two-Beam Accelerator",

  17. Two-Dimensional Simulation Analysis of the Standing-wave Free-electron Laser Two-Beam Accelerator

    E-Print Network [OSTI]

    Wang, C.

    2008-01-01T23:59:59.000Z

    Standing-wave free-electron laser two-beam accelerator,"of a standing-wave free-electron laser," Lawrence Berkeleyof a standing-wave free-electron laser," Lawrence Berkeley

  18. Multicolor operation and spectral control in a gain-modulated x-ray free-electron laser

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    The Physics of Free Electron Lasers (Springer, Berlin, [33]Gain-Modulated X-Ray Free-Electron Laser A. Marinelli, 1, *emission x-ray free-electron laser can be controlled by

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

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    codes: (140.2600) Free-electron lasers (FELs); (140.3300)The Development of X-Ray Free-Electron Lasers,” IEEE J. Sel.and M.N. Rosenbluth, “Free-Electron Lasers with Variable

  20. Calculation of 3-D Free Electron Laser Gain: Comparison with Simulation and Generalization to Elliptical Cross Section

    E-Print Network [OSTI]

    Chin, Y.-H.

    2011-01-01T23:59:59.000Z

    Calculation of 3-D Free Electron Laser Gain: Comparison withInternational Free Electron Laser Conference, Kobe, Japan,relation for the free electron laser (FEL) gain in the

  1. Free-Electron Laser Generation of VUV and X-Ray Radiation using a Conditioned Beam and Ion-Channel Focusing

    E-Print Network [OSTI]

    Yu, L.-H.

    2008-01-01T23:59:59.000Z

    a) Accelerator Conditioner Free-Electron Laser L ---~>~ . Free Electron Laser Conference, Santain the Proceedings Free-Electron Laser Generation of VUV and

  2. Pair Production from Vacuum at the Focus of an X-Ray Free Electron Laser

    E-Print Network [OSTI]

    A. Ringwald

    2001-03-16T23:59:59.000Z

    There are definite plans for the construction of X-ray free electron lasers (FEL), both at DESY, where the so-called XFEL is part of the design of the electron-positron linear collider TESLA, as well as at SLAC, where the so-called Linac Coherent Light Source (LCLS) has been proposed. Such an X-ray laser would allow for high-field science applications: One could make use of not only the high energy and transverse coherence of the X-ray beam, but also of the possibility of focusing it to a spot with a small radius, hopefully in the range of the laser wavelength. Along this route one obtains very large electric fields, much larger than those obtainable with any optical laser of the same power. In this letter we discuss the possibility of obtaining an electric field so high that electron-positron pairs are spontaneously produced in vacuum (Schwinger pair production). We find that if X-ray optics can be improved to approach the diffraction limit of focusing, and if the power of the planned X-ray FELs can be increased to the terawatt region, then there is ample room for an investigation of the Schwinger pair production mechanism.

  3. Theoretical computation of the polarization characteristics of an X-ray Free-Electron Laser with planar undulator

    E-Print Network [OSTI]

    Geloni, Gianluca; Saldin, Evgeni

    2015-01-01T23:59:59.000Z

    We show that radiation pulses from an X-ray Free-Electron Laser (XFEL) with a planar undulator, which are mainly polarized in the horizontal direction, exhibit a suppression of the vertical polarization component of the power at least by a factor $\\lambda_w^2/(4 \\pi L_g)^2$, where $\\lambda_w$ is the length of the undulator period and $L_g$ is the FEL field gain length. We illustrate this fact by examining the XFEL operation under the steady state assumption. In our calculations we considered only resonance terms: in fact, non resonance terms are suppressed by a factor $\\lambda_w^3/(4 \\pi L_g)^3$ and can be neglected. While finding a situation for making quantitative comparison between analytical and experimental results may not be straightforward, the qualitative aspects of the suppression of the vertical polarization rate at XFELs should be easy to observe. We remark that our exact results can potentially be useful to developers of new generation FEL codes for cross-checking their results.

  4. Generation of ultrashort radiation pulses by injection locking a regenerative free-electron-laser amplifier

    E-Print Network [OSTI]

    Wurtele, Jonathan

    Generation of ultrashort radiation pulses by injection locking a regenerative free-electron-laser 12609-5 PACS number s : 41.60.Cr, 42.60.Da I. INTRODUCTION AND MOTIVATION The free-electron laser FEL demonstrate how a steady-state train of ultrashort radiation pulses can be produced utilizing a new free-electron

  5. Absorbed XFEL dose in the components of the LCLS X-Ray Optics

    SciTech Connect (OSTI)

    Hau-Riege, S

    2005-09-27T23:59:59.000Z

    We list the materials that are anticipated to be placed into the Linac Coherent Light Source (LCLS) x-ray free electron laser (XFEL) beam line, their positions, and the absorbed dose, and compare this dose with anticipated damage thresholds.

  6. Design Alternatives for a Free Electron Laser Facility

    SciTech Connect (OSTI)

    Jacobs, K; Bosch, R A; Eisert, D; Fisher, M V; Green, M A; Keil, R G; Kleman, K J; Kulpin, J G; Rogers, G C; Wehlitz, R; Chiang, T; Miller, T J; Lawler, J E; Yavuz, D; Legg, R A

    2012-07-01T23:59:59.000Z

    The University of Wisconsin-Madison is continuing design efforts for a vacuum ultraviolet/X-ray Free Electron Laser facility. The design incorporates seeding the FEL to provide fully coherent photon output at energies up to {approx}1 keV. The focus of the present work is to minimize the cost of the facility while preserving its performance. To achieve this we are exploring variations in the electron beam driver for the FEL, in undulator design, and in the seeding mechanism. Design optimizations and trade-offs between the various technologies and how they affect the FEL scientific program will be presented.

  7. Compact two-beam push-pull free electron laser

    DOE Patents [OSTI]

    Hutton, Andrew (Yorktown, VA)

    2009-03-03T23:59:59.000Z

    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.

  8. A Free-Electron Laser in the Pulsar Magnetosphere

    E-Print Network [OSTI]

    P. -K. Fung; J. Kuijpers

    2004-05-18T23:59:59.000Z

    We have studied systematically the free-electron laser in the context of high brightness pulsar radio emission. In this paper, we have numerically examined the case where a transverse electromagnetic wave is distorting the motion of a relativistic electron beam while travelling over one stellar radius ($ approx 10 :{km}$). For different sets of parameters, coherent emission is generated by bunches of beam electrons in the radio domain, with bandwidths of 3 GHz. Pulse power often reached $10^{13} :{W}$, which corresponds with brightness temperature of $10^{30} :{K}$. The duration of these pulses is of the order of nanoseconds. In the context of pulsar radio emission, our results indicate that the laser can produce elementary bursts of radiation which build up the observed microstructures of a few tens of microseconds duration. The process is sensitive mostly to the beam particles energy, number density and the background magnetic field, but much less so to the transverse wave parameters. We demonstrate that the operation of a free-electron laser with a transverse electromagnetic wiggler in the pulsar magnetosphere occurs preferably at moder ate Lorentz factors $ gamma geq 100$, high beam density $n gtrsim 0.1 n_{textrm{GJ}}(r_ ast)$ where $n_{textrm{GJ}}(r_ ast)$ is the Goldrei ch-Julian density at a stellar radius $r_ ast$, and finally, at large altitude where the background magnetic field is low $B_0 leq 10^{-2} textrm{T}$.

  9. Pulsed laser deposition with a high average power free electron laser: Benefits of subpicosecond pulses with high repetition rate

    E-Print Network [OSTI]

    Reilly, Anne

    Pulsed laser deposition with a high average power free electron laser: Benefits of subpicosecond average power Thomas Jefferson National Accelerator Facility Free Electron Laser. The combination of the free electron laser leads to very different plasma emission and produces films with high quality

  10. Pair Creation and an X-ray Free Electron Laser

    E-Print Network [OSTI]

    R. Alkofer; M. B. Hecht; C. D. Roberts; S. M. Schmidt; D. V. Vinnik

    2001-08-17T23:59:59.000Z

    Using a quantum kinetic equation coupled to Maxwell's equation we study the possibility that focused beams at proposed X-ray free electron laser facilities can generate electric field strengths large enough to cause spontaneous electron-positron pair production from the QED vacuum. Our approach yields the time and momentum dependence of the single particle distribution function. Under conditions reckoned achievable at planned facilities, repeated cycles of particle creation and annihilation take place in tune with the laser frequency. However, the peak particle number density is insensitive to this frequency and one can anticipate the production of a few hundred particle pairs per laser period. Field-current feedback and quantum statistical effects are small and can be neglected in this application of non-equilibrium quantum mean field theory.

  11. Beam conditioner for free electron lasers and synchrotrons

    DOE Patents [OSTI]

    Liu, H.; Neil, G.R.

    1998-09-08T23:59:59.000Z

    A focused optical has been used to introduce an optical pulse, or electromagnetic wave, collinear with the electron beam in a free electron laser or synchrotron thereby adding an axial field component that accelerates the electrons on the radial outside of the distribution of electrons in the electron beam. This invention consists of using the axial electrical component of a TEM{sub 10} mode Gaussian beam in vacuum to condition the electron beam and speed up the outer electrons in the beam. The conditioning beam should possess about the same diameter as the electron beam. The beam waist of the conditioning wave must be located around the entrance of the undulator longitudinally to have a net energy exchange between the electrons in the outer part of the distribution and the conditioning wave owing to the natural divergence of a Gaussian beam. By accelerating the outer electrons, the outer and core electrons are caused to stay in phase. This increases the fraction of the electron beam energy that is converted to light thereby improving the efficiency of conversion of energy to light and therefore boosting the power output of the free electron laser and synchrotron. 4 figs.

  12. Beam conditioner for free electron lasers and synchrotrons

    DOE Patents [OSTI]

    Liu, Hongxiu (Williamsburg, VA); Neil, George R. (Williamsburg, VA)

    1998-01-01T23:59:59.000Z

    A focused optical is been used to introduce an optical pulse, or electromagnetic wave, colinearly with the electron beam in a free electron laser or synchrotron thereby adding an axial field component that accelerates the electrons on the radial outside of the distribution of electrons in the electron beam. This invention consists of using the axial electrical component of a TEM.sub.10 mode Gaussian beam in vacuum to condition the electron beam and speed up the outer electrons in the beam. The conditioning beam should possess about the same diameter as the electron beam. The beam waist of the conditioning wave must be located around the entrance of the undulator longitudinally to have a net energy exchange between the electrons in the outer part of the distribution and the conditioning wave owing to the natural divergence of a Gaussian beam. By accelerating the outer electrons, the outer and core electrons are caused to stay in phase. This increases the fraction of the electron beam energy that is converted to light thereby improving the efficiency of conversion of energy to light and therefore boosting the power output of the free electron laser and synchrotron.

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

    SciTech Connect (OSTI)

    Nilsen, J; Rohringer, N

    2011-08-30T23:59:59.000Z

    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.

  14. 5 (Upgradable to 25 keV) Free Electron Laser (FEL) Facility

    E-Print Network [OSTI]

    York, R C

    2013-01-01T23:59:59.000Z

    A Free Electron Laser (FEL) facility utilizing a recirculated Superconducting Radio Frequency (SRF) linear accelerator (linac) provides the opportunity to achieve about five times greater photon energy than an unrecirculated linac of similar cost. > A 4 GeV SRF, cw, electron linac can be used to drive an FEL producing 5 keV photons. The SLAC National Accelerator Laboratory, a Department of Energy (DOE) Basic Energy Sciences (BES) laboratory, proposes to utilize a 4 GeV unrecirculated, SRF, linac in a segment of existing linac tunnel. > For an initial investment similar to that of the proposed SLAC strategy, a recirculated SRF linac system could deliver the 4 GeV electrons for photon energies of 5 keV and provide an upgrade path to photon energies of 25 keV. > Further support amounting to about a third of the initial investment would provide upgrade funds for additional SRF linac and cryogenic capacity sufficient to provide electron energies appropriate for 25 keV photons matching the European XFEL.

  15. 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...

  16. A wide bandwidth free-electron laser with mode locking using current modulation.

    SciTech Connect (OSTI)

    Kur, E.; Dunning, D. J.; McNeil, B. W. J.; Wurtele, J.; Zholents, A. A. (Accelerator Systems Division (APS)); (Univ. of California at Berkeley); (Univ. of Strathclyde); (STFC Daresbury Lab.); (LBNL)

    2011-01-20T23:59:59.000Z

    A new scheme for mode locking a free-electron laser amplifier is proposed based on electron beam current modulation. It is found that certain properties of the original concept, based on the energy modulation of electrons, are improved including the spectral brightness of the source and the purity of the series of short pulses. Numerical comparisons are made between the new and old schemes and between a mode-locked free-electron laser and self-amplified spontaneous emission free-electron laser. Illustrative examples using a hypothetical mode-locked free-electron laser amplifier are provided. The ability to generate intense coherent radiation with a large bandwidth is demonstrated.

  17. CONTROL SYSTEM FOR MAGNET POWER SUPPLIES FOR NOVOSIBIRSK FREE ELECTRON LASER

    E-Print Network [OSTI]

    Kozak, Victor R.

    CONTROL SYSTEM FOR MAGNET POWER SUPPLIES FOR NOVOSIBIRSK FREE ELECTRON LASER Yu.M.Velikanov, V, the software tools for power supply diagnostics are described. INTRODUCTION A high-power free electron laser electron laser (FEL) is described. The characteristics and structure of the power supply system

  18. XUV free-electron laser-based projection lithography systems

    SciTech Connect (OSTI)

    Newnam, B.E.

    1990-01-01T23:59:59.000Z

    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.

  19. Thermal effect on prebunched two-beam free electron laser

    SciTech Connect (OSTI)

    Mirian, N. S. [School of Particle and Accelerator Physics, Institute for Research in Fundamental Sciences (IPM), 19395-5531 Tehran (Iran, Islamic Republic of)] [School of Particle and Accelerator Physics, Institute for Research in Fundamental Sciences (IPM), 19395-5531 Tehran (Iran, Islamic Republic of); Maraghechi, B. [Department of Physics, Amirkabir University of Technology, 15875-4413 Tehran (Iran, Islamic Republic of)] [Department of Physics, Amirkabir University of Technology, 15875-4413 Tehran (Iran, Islamic Republic of)

    2013-08-15T23:59:59.000Z

    A numerical simulation in one-dimension is conducted to study the two-beam free electron laser. The fundamental resonance of the fast electron beam coincides with the fifth harmonic of the slow electron beam in order to generate extreme ultraviolet radiation. Thermal effect in the form of the longitudinal velocity spread is included in the analysis. In order to reduce the length of the wiggler, prebunched slow electron beam is considered. The evaluation of the radiation power, bunching parameter, distribution function of energy, and the distribution function of the pondermotive phase is studied. Sensitivity of the power of the fifth harmonic to the jitter in the energy difference between the two beams is also studied. A phase space is presented that shows the trapped electrons at the saturation point.

  20. Free-Electron Laser-Powered Electron Paramagnetic Resonance Spectroscopy

    E-Print Network [OSTI]

    Takahashi, S; Edwards, D T; van Tol, J; Ramian, G; Han, S; Sherwin, M S

    2012-01-01T23:59:59.000Z

    Electron paramagnetic resonance (EPR) spectroscopy interrogates unpaired electron spins in solids and liquids to reveal local structure and dynamics; for example, EPR has elucidated parts of the structure of protein complexes that have resisted all other techniques in structural biology. EPR can also probe the interplay of light and electricity in organic solar cells and light-emitting diodes, and the origin of decoherence in condensed matter, which is of fundamental importance to the development of quantum information processors. Like nuclear magnetic resonance (NMR), EPR spectroscopy becomes more powerful at high magnetic fields and frequencies, and with excitation by coherent pulses rather than continuous waves. However, the difficulty of generating sequences of powerful pulses at frequencies above 100 GHz has, until now, confined high-power pulsed EPR to magnetic fields of 3.5 T and below. Here we demonstrate that ~1 kW pulses from a free-electron laser (FEL) can power a pulsed EPR spectrometer at 240 GHz...

  1. Ultraviolet Free Electron Laser Facility preliminary design report

    SciTech Connect (OSTI)

    Ben-Zvi, I. [ed.

    1993-02-01T23:59:59.000Z

    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).

  2. A Free-Electron Laser in the Pulsar Magnetosphere

    E-Print Network [OSTI]

    Kuijpers, P K F J

    2004-01-01T23:59:59.000Z

    We have studied systematically the free-electron laser in the context of high brightness pulsar radio emission. In this paper, we have numerically examined the case where a transverse electromagnetic wave is distorting the motion of a relativistic electron beam while travelling over one stellar radius ($ approx 10 :{km}$). For different sets of parameters, coherent emission is generated by bunches of beam electrons in the radio domain, with bandwidths of 3 GHz. Pulse power often reached $10^{13} :{W}$, which corresponds with brightness temperature of $10^{30} :{K}$. The duration of these pulses is of the order of nanoseconds. In the context of pulsar radio emission, our results indicate that the laser can produce elementary bursts of radiation which build up the observed microstructures of a few tens of microseconds duration. The process is sensitive mostly to the beam particles energy, number density and the background magnetic field, but much less so to the transverse wave parameters. We demonstrate that th...

  3. TESLA-FEL Report 2004-08 LINAC BASED FREE-ELECTRON LASER

    E-Print Network [OSTI]

    TESLA-FEL Report 2004-08 1 LINAC BASED FREE-ELECTRON LASER J. Rossbach Universität Hamburg, Hamburg, Germany Abstract A basic treatment of the principle of the linac-driven free-electron laser (FEL) is given. The first part of the paper describes the FEL in low-gain approximation, and in the second part the high

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

    SciTech Connect (OSTI)

    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

    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.

  5. Analysis of \\v{C}erenkov free-electron lasers

    E-Print Network [OSTI]

    Kalkal, Yashvir

    2014-01-01T23:59:59.000Z

    We present an analysis of a \\v{C}erenkov free-electron laser (FEL) driven by a flat electron beam. In this system, an electron beam travelling close to a dielectric slab placed at the top of an ideal conductor interacts with the co-propagating electromagnetic surface mode. The surface mode arises due to singularity in the reflectivity of the dielectric slab for the incident evanescent wave. Under suitable conditions, the surface mode grows as a result of interaction with the electron beam. We show that the interaction of the surface mode with the co-propagating electron beam can be rigorously understood by analyzing the singularity in the reflectivity. Using this approach, we set up coupled Maxwell-Lorentz equations for the system, in analogy with conventional undulator based FELs. We solve these equations analytically in the small signal regime to obtain formulae for the small signal gain, and the spatial growth rate. Saturation behaviour of the system is analyzed by solving these equations numerically in th...

  6. The History of X-ray Free-Electron Lasers

    SciTech Connect (OSTI)

    Pellegrini, C.; /UCLA /SLAC; ,

    2012-06-28T23:59:59.000Z

    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.

  7. Analytic model of bunched beams for harmonic generation in the low-gain free electron laser regime

    E-Print Network [OSTI]

    Wurtele, Jonathan

    Analytic model of bunched beams for harmonic generation in the low-gain free electron laser regime employs free electron lasers (FELs) with two undulators: the first uses a seed laser to modulate Many proposed x-ray free electron lasers (FELs) are designed to produce radiation starting from

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

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Free electron properties of metals under ultrafast laser-induced electron-phonon nonequilibrium modelled based on the free electron classical theory, the free electron number is a key parameter. However or delocalized electronic states, temperature dependent free electron numbers are evaluated for a series

  9. IEEEJOURNAL OF QUANTUMELECTRONICS, VOL. QE-21,NO. 7, JULY 1985 831 High-Gain Free Electron Lasers Using Induction

    E-Print Network [OSTI]

    Wurtele, Jonathan

    IEEEJOURNAL OF QUANTUMELECTRONICS, VOL. QE-21,NO. 7, JULY 1985 831 High-Gain Free Electron Lasers, AND J. S. WURTELE Abstract-High-power free electron lasers (FEL's) can be realized using induction. INTRODUCTION THE free electron laser (FEL)[11 can produce coherent radiation at wavelengths from

  10. Beam conditioning for free electron lasers: Consequences and methods A. Wolski, G. Penn, A. Sessler, and J. Wurtele*

    E-Print Network [OSTI]

    Wurtele, Jonathan

    Beam conditioning for free electron lasers: Consequences and methods A. Wolski, G. Penn, A. Sessler cases [VISA, a soft x-ray free-electron laser (FEL), LCLS, and a ``Greenfield'' FEL] are examined short-wavelength free-electron lasers (FELs) demands electron beams with very small transverse emittance

  11. Constraints on photon pulse duration from longitudinal electron beam diagnostics at a soft X-ray free-electron laser

    E-Print Network [OSTI]

    -ray free-electron laser C. Behrens1 , N. Gerasimova1 , Ch. Gerth1 , B. Schmidt1 , E.A. Schneidmiller1 , S, Ukraine (Dated: February 28, 2012) The successful operation of X-ray free-electron lasers (FELs), like the Linac Coherent Light Source or the Free-Electron Laser in Hamburg (FLASH), makes unprecedented research

  12. An Infrared Free Electron Laser System for the Proposed Chemical Dynamics Research Laboratory at LBL Based on a 500 MHz Superconducting Linac

    E-Print Network [OSTI]

    Kim, K.-J.

    2011-01-01T23:59:59.000Z

    International Free Electron Laser Conference, Kobe, Japan,2 i An Infrared Free Electron Laser System for the ProposedDE93 004723 AN INFRARED FREE ELECTRON LASER SYSTEM FOR THE

  13. Design of a Superconducting Linear Accelerator for an Infrared Free Electron Laser of the Proposed Chemical Dynamics Research Laboratory at LBL

    E-Print Network [OSTI]

    Chattopadhyay, S.

    2011-01-01T23:59:59.000Z

    see "An Infrared Free-Electron Laser for CDRL," LBL Pub-FOR AN INFRARED FREE ELECTRON LASER OF 1HE PROPOSED CHEMICALFOR AN INFRARED FREE ELECTRON LASER OF THE PROPOSED CHEMICAL

  14. Two Dimensional Simulation Analysis of the First Sections of a Standing-Wave Free-Electron Laser Two-Beam Accelerator

    E-Print Network [OSTI]

    Wang, C.

    2008-01-01T23:59:59.000Z

    Standing-wave free-electron laser two-beam accelerator,"of a standing-wave free electron laser," Nucl. Instr. anda standing-wave free-electron laser," Proc. SPIE Conference

  15. High-Gain Harmonic Generation Free-Electron Laser at Saturation

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

    Gain Harmonic Generation Free-Electron Laser at Saturation T. Shaftan 1 , M. Babzien 1 , I. Ben-Zvi 1 , S. G. Biedron 2 , L. F. DiMauro 1 , A. Doyuran 1 , J.N. Galayda 2 , E....

  16. Jefferson Lab's Free-Electron Laser Joins With Others in New...

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

    Free-Electron Laser Joins With Others in New Research Venture NEWPORT NEWS, VA, April 29, 2009 - The U.S. Department of Energy's Thomas Jefferson National Accelerator Facility will...

  17. Correspondence: Email: shinn@jlab.org; Telephone: 757 269 7565; FAX: 757 269 5519 High Average Power Free-Electron Lasers -A New Laser Source for

    E-Print Network [OSTI]

    Power Free-Electron Lasers - A New Laser Source for Materials Processing Michelle D. Shinn Thomas the status of our DOD-funded project to upgrade the FEL to 10 kW in the mid IR. Keywords: Free-electron laser, one type of laser can meet these requirements: a free-electron laser (FEL) using a superconducting

  18. Preparations for a high gradient inverse free electron laser experiment at Brookhaven national laboratory

    SciTech Connect (OSTI)

    Duris, J.; Li, R. K.; Musumeci, P.; Sakai, Y.; Threlkeld, E.; Williams, O.; Fedurin, M.; Kusche, K.; Pogorelsky, I.; Polyanskiy, M.; Yakimenko, V. [UCLA Department of Physics and Astronomy, Los Angeles, CA 90095 (United States); Accelerator Test Facility, Brookhaven National Laboratory, Upton, NY, 11973 (United States)

    2012-12-21T23:59:59.000Z

    Preparations for an inverse free electron laser experiment at Brookhaven National Laboratory's Accelerator Test Facilty are presented. Details of the experimental setup including beam and laser transport optics are first discussed. Next, the driving laser pulse structure is investigated and initial diagnostics are explored and compared to simulations. Finally, planned improvements to the experimental setup are discussed.

  19. Free Electron Laser Nitriding of Metals: From basis physics to industrial applications

    E-Print Network [OSTI]

    Rapin, Gerd

    Accelerator Facility, Free Electron Laser Group, Newport News, VA 23606, USA Abstract Titanium was laser-liquid interface energy and the strain. Further in- vestigations showed that the dendritic growth is beginning treatment, laser nitriding, titanium PACS: 81.65.Lp, 52.50.Jm, 61.80.Ba, 76.80.+y 1 Introduction Titanium

  20. A revised partiality model and post-refinement algorithm for X-ray free-electron laser data

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

    Ginn, Helen Mary; Brewster, Aaron S.; Hattne, Johan; Evans, Gwyndaf; Wagner, Armin; Grimes, Jonathan M.; Sauter, Nicholas K.; Sutton, Geoff; Stuart, David Ian

    2015-06-01T23:59:59.000Z

    Research towards using X-ray free-electron laser (XFEL) data to solve structures using experimental phasing methods such as sulfur single-wavelength anomalous dispersion (SAD) has been hampered by shortcomings in the diffraction models for X-ray diffraction from FELs. Owing to errors in the orientation matrix and overly simple partiality models, researchers have required large numbers of images to converge to reliable estimates for the structure-factor amplitudes, which may not be feasible for all biological systems. Here, data for cytoplasmic polyhedrosis virus type 17 (CPV17) collected at 1.3 Å wavelength at the Linac Coherent Light Source (LCLS) are revisited. A previously published definitionmore »of a partiality model for reflections illuminated by self-amplified spontaneous emission (SASE) pulses is built upon, which defines a fraction between 0 and 1 based on the intersection of a reflection with a spread of Ewald spheres modelled by a super-Gaussian wavelength distribution in the X-ray beam. A method of post-refinement to refine the parameters of this model is suggested. This has generated a merged data set with an overall discrepancy (by calculating theRsplitvalue) of 3.15% to 1.46 Å resolution from a 7225-image data set. The atomic numbers of C, N and O atoms in the structure are distinguishable in the electron-density map. There are 13 S atoms within the 237 residues of CPV17, excluding the initial disordered methionine. These only possess 0.42 anomalous scattering electrons each at 1.3 Å wavelength, but the 12 that have single predominant positions are easily detectable in the anomalous difference Fourier map. It is hoped that these improvements will lead towards XFEL experimental phase determination and structure determination by sulfur SAD and will generally increase the utility of the method for difficult cases.« less

  1. Electron beam transport in gas-loaded free-electron lasers

    SciTech Connect (OSTI)

    Yariv, S.; Friedland, L. (Center for Plasma Physics, Racah Institute of Physics, Hebrew University of Jerusalem, Jerusalem, Israel (IL))

    1990-12-01T23:59:59.000Z

    The effects of the presence of helical wiggler and axial guide magnetic fields on the quality of the electron beam in a gas-loaded free-electron laser are investigated. The electron velocity space diffusion theory in the free-electron laser is developed and tested in Monte Carlo simulations. The theory is applied in estimating the collisional limitations on the interaction length of the laser. It is shown that two competing effects related to collisions cause the gain loss in gas-loaded free-electron lasers, i.e., (a) the growing phase mismatch between the electrons and the wave and (b) the destruction of the coherent transverse helical beam motion. The second effect dominates in the absence of the guide field, provided the wiggler field strength is sufficiently small.

  2. X-ray Free-Electron Lasers - Present and Future Capabilities [Invited

    SciTech Connect (OSTI)

    Galayda, John; Ratner, John Arthur:a Daniel F.; White, William E.; /SLAC

    2011-11-16T23:59:59.000Z

    The Linac Coherent Light Source is now in operation as an X-ray free-electron laser (FEL) user facility. It produces coherent pulses of 550-10,000 eV X-rays of duration adjustable from <10 fsto500 fs. Typical peak power is in excess of 20 GW. The facility will soon be joined by several X-ray FELs under construction around the world. This article will provide an abridged history of free-electron lasers, a description of some basic physics regarding free-electron laser light amplification, and an overview of the rapidly growing list of examples in which lasers will be used in the control and operation of X-ray FELs.

  3. BUDKER INP FREE ELECTRON LASER FACILITY CURRENT STATUS AND FUTURE PROSPECTS *

    E-Print Network [OSTI]

    Kozak, Victor R.

    BUDKER INP FREE ELECTRON LASER FACILITY ­ CURRENT STATUS AND FUTURE PROSPECTS * O.A.Shevchenko# , V electron laser (FEL) facility at Budker INP is being developed for more than 15 years. It is based.G.Tcheskidov, N.A.Vinokurov, M.G.Vlasenko, P.D.Vobly, V.N.Volkov, BINP, Novosibirsk, Russia Abstract The free

  4. Part 2: Coherent emission from Free Electron Lasers

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

    Lawr, Whit. Several laser-based techniques have been used to generate ultrashort x-ray pulses including laser-driven plasmas Murn, Alte, Risc, Rose, Zamp, high-order harmonic...

  5. Density gradient free electron collisionally excited X-ray laser

    DOE Patents [OSTI]

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

    1989-01-01T23:59:59.000Z

    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.

  6. Density gradient free electron collisionally excited x-ray laser

    DOE Patents [OSTI]

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

    1984-11-29T23:59:59.000Z

    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.

  7. Navy Breaks World Record With Futuristic Free-Electron Laser...

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

    foxnews.comscitech20110218navy-breaks-world-record-futuristic-laser-getting-real Submitted: Sunday, February 20, 2011...

  8. Two-colour generation in a chirped seeded Free-Electron Laser

    E-Print Network [OSTI]

    Mahieu, B; Castronovo, D; Danailov, M B; Demidovich, A; De Ninno, G; Di Mitri, S; Fawley, W M; Ferrari, E; Fröhlich, L; Gauthier, D; Giannessi, L; Mahne, N; Penco, G; Raimondi, L; Spampinati, S; Spezzani, C; Svetina, C; Trovò, M; Zangrando, M

    2013-01-01T23:59:59.000Z

    We present the experimental demonstration of a method for generating two spectrally and temporally separated pulses by an externally seeded, single-pass free-electron laser operating in the extreme-ultraviolet spectral range. Our results, collected on the FERMI@Elettra facility and confirmed by numerical simulations, demonstrate the possibility of controlling both the spectral and temporal features of the generated pulses. A free-electron laser operated in this mode becomes a suitable light source for jitter-free, two-colour pump-probe experiments.

  9. Aerosol Imaging with a Soft X-ray Free Electron Laser

    SciTech Connect (OSTI)

    Bogan, Michael J.; /SLAC /LLNL, Livermore; Boutet, Sebastien; /SLAC; Chapman, Henry N.; /DESY /Hamburg U.; Marchesini, Stefano; /LBL, Berkeley; Barty, Anton; Benner, W.Henry /LLNL, Livermore; Rohner, Urs; /LLNL, Livermore /TOFWERK AG; Frank, Matthias; Hau-Riege, Stefan P.; /LLNL, Livermore; Bajt, Sasa; /DESY; Woods, Bruce; /LLNL, Livermore; Seibert, M.M.; Iwan, Bianca; Timneanu, Nicusor; Hajdu, Janos; /Uppsala U.; Schulz, Joachim; /DESY

    2011-08-22T23:59:59.000Z

    Lasers have long played a critical role in the advancement of aerosol science. A new regime of ultrafast laser technology has recently be realized, the world's first soft xray free electron laser. The Free electron LASer in Hamburg, FLASH, user facility produces a steady source of 10 femtosecond pulses of 7-32 nm x-rays with 10{sub 12} photons per pulse. The high brightness, short wavelength, and high repetition rate (>500 pulses per second) of this laser offers unique capabilities for aerosol characterization. Here we use FLASH to perform the highest resolution imaging of single PM2.5 aerosol particles in flight to date. We resolve to 35 nm the morphology of fibrous and aggregated spherical carbonaceous nanoparticles that existed for less than two milliseconds in vacuum. Our result opens the possibility for high spatialand time-resolved single particle aerosol dynamics studies, filling a critical technological need in aerosol science.

  10. Master-Oscillator-Power-Amplifier (MOPA) Laser Sources Used as Drive Lasers for Photoinjectors for High-Gain, Free Electron Lasers (FELs)

    E-Print Network [OSTI]

    Anlage, Steven

    for High-Gain, Free Electron Lasers (FELs) By David Leonard Demske Scholarly paper submitted In partial Milchberg #12;- 1 - Abstract The realization of extremely high gain, and high power in Free Electron Lasers laser arrangements to extract electron bunches from photocathodes. The performance of FELs depends

  11. Modelling dynamics of samples exposed to free-electron-laser radiation with Boltzmann equations

    E-Print Network [OSTI]

    Beata Ziaja; Antonio R. B. de Castro; Edgar Weckert; Thomas Moeller

    2005-12-20T23:59:59.000Z

    We apply Boltzmann equations for modelling the radiation damage in samples irradiated by photons from free electron laser (FEL). We test this method in a study case of a spherically symmetric xenon cluster irradiated with VUV FEL photons. The results obtained demonstrate the potential of the Boltzmann method for describing the complex and non-equilibrium dynamics of samples exposed to FEL radiation.

  12. ABSTRACT FINAL ID: SM13B-2055 TITLE: Whistler amplification: a free electron laser in the Earth's magnetosphere

    E-Print Network [OSTI]

    Ng, Chung-Sang

    ABSTRACT FINAL ID: SM13B-2055 TITLE: Whistler amplification: a free electron laser in the Earth on the similarities between free electron lasers (FELs) and whistler mode emissions, we present here a new set in the Earth's magnetosphere that arise due to the interaction of whistler waves with radiation belt electrons

  13. Status of the Los Alamos Free-Electron Laser

    SciTech Connect (OSTI)

    Watson, J.M.

    1985-01-01T23:59:59.000Z

    Since the initial oscillator experiments were completed last year, the Los Alamos FEL has undergone some major modifications and additions in preparation for the next set of experiments. The laser performance is projected to be substantially enhanced, the rf energy-recovery technique will be demonstrated, and FEL physics measurements will be expanded. The accelerator is now being tuned with very promising performance. The above experiments will be completed during the next year.

  14. The First Angstrom X-Ray Free-Electron Laser

    SciTech Connect (OSTI)

    Galayda, John; /SLAC

    2012-08-24T23:59:59.000Z

    The Linac Coherent Light Source produced its first x-ray laser beam on 10 April 2009. Today it is routinely producing x-ray pulses with energy >2 mJ across the operating range from 820-8,200 eV. The facility has begun operating for atomic/molecular/optical science experiments. Performance of the facility in its first user run (1 October - 21 December) and current machine development activities will be presented. Early results from the preparations for the start of the second user run is also reported.

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

    E-Print Network [OSTI]

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

    2014-02-27T23:59:59.000Z

    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.

  16. Self-Induced Harmonic Generation in a Storage-Ring Free-Electron Laser

    SciTech Connect (OSTI)

    De Ninno, G. [University of Nova Gorica (Slovenia); Sincrotrone Trieste, Basovizza (Trieste) (Italy); Allaria, E.; Danailov, M. B.; Diviacco, B.; Ferianis, M.; Karantzoulis, E.; Spezzani, C.; Trovo, M. [Sincrotrone Trieste, Basovizza (Trieste) (Italy); Coreno, M. [TASC-INFM National Laboratory, Basovizza (Trieste) (Italy); Chowdhury, S. [Xerox Research Center, Webster, New York (United States); Curbis, F. [Sincrotrone Trieste, Basovizza (Trieste) (Italy); University of Trieste (Italy); Longhi, E. C. [Diamond Light Source, Oxfordshire (United Kingdom); Pinayev, I. V.; Litvinenko, V. N. [Brookhaven National Laboratory, Upton, New York (United States)

    2008-03-14T23:59:59.000Z

    Coherent radiation from a relativistic electron beam is a valuable way to overcome the present limitations of conventional lasers and synchrotron radiation light sources. The typical scheme has electrons, directly from a linac, in a single-pass interaction with a laser pulse in the presence of a static undulator magnetic field. We demonstrate that a storage-ring free-electron laser can also achieve harmonic generation (down to 36.5 nm), presenting both experimental and theoretical results, and offer a reliable interpretation of the peculiar underlying physical processes involved.

  17. An extreme ultraviolet Michelson interferometer for experiments at free-electron lasers

    SciTech Connect (OSTI)

    Hilbert, Vinzenz; Fuchs, Silvio; Paulus, Gerhard G.; Zastrau, Ulf [Institute of Optics and Quantum Electronics, Friedrich-Schiller University Jena, Max-Wien-Platz 1, 07743 Jena (Germany)] [Institute of Optics and Quantum Electronics, Friedrich-Schiller University Jena, Max-Wien-Platz 1, 07743 Jena (Germany); Blinne, Alexander [Institute for Theoretical Physics, Friedrich-Schiller University Jena, Max-Wien-Platz 1, 07743 Jena (Germany)] [Institute for Theoretical Physics, Friedrich-Schiller University Jena, Max-Wien-Platz 1, 07743 Jena (Germany); Feigl, Torsten [Fraunhofer Institute for Applied Optics and Precision Engineering, Albert-Einstein-Straße 7, 07745 Jena (Germany)] [Fraunhofer Institute for Applied Optics and Precision Engineering, Albert-Einstein-Straße 7, 07745 Jena (Germany); Kämpfer, Tino; Rödel, Christian; Uschmann, Ingo; Wünsche, Martin; Förster, Eckhart [Institute of Optics and Quantum Electronics, Friedrich-Schiller University Jena, Max-Wien-Platz 1, 07743 Jena (Germany) [Institute of Optics and Quantum Electronics, Friedrich-Schiller University Jena, Max-Wien-Platz 1, 07743 Jena (Germany); Helmholtz Institute, Fröbelstieg 3, 07743 Jena (Germany)

    2013-09-15T23:59:59.000Z

    We present a Michelson interferometer for 13.5 nm soft x-ray radiation. It is characterized in a proof-of-principle experiment using synchrotron radiation, where the temporal coherence is measured to be 13 fs. The curvature of the thin-film beam splitter membrane is derived from the observed fringe pattern. The applicability of this Michelson interferometer at intense free-electron lasers is investigated, particularly with respect to radiation damage. This study highlights the potential role of such Michelson interferometers in solid density plasma investigations using, for instance, extreme soft x-ray free-electron lasers. A setup using the Michelson interferometer for pseudo-Nomarski-interferometry is proposed.

  18. Effects of free-electron-laser field fluctuations on the frequency response of driven atomic resonances

    E-Print Network [OSTI]

    G. M. Nikolopoulos; P. Lambropoulos

    2012-09-11T23:59:59.000Z

    We study the effects of field fluctuations on the total yields of Auger electrons, obtained in the excitation of neutral atoms to a core-excited state by means of short-wavelength free-electron-laser pulses. Beginning with a self-contained analysis of the statistical properties of fluctuating free-electron-laser pulses, we analyse separately and in detail the cases of single and double Auger resonances, focusing on fundamental phenomena such as power broadening and ac Stark (Autler-Townes) splitting. In certain cases, field fluctuations are shown to influence dramatically the frequency response of the resonances, whereas in other cases the signal obtained may convey information about the bandwidth of the radiation as well as the dipole moment between Auger states.

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

    SciTech Connect (OSTI)

    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

    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.

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

    SciTech Connect (OSTI)

    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

    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.

  1. Ablation of solids using a femtosecond extreme ultraviolet free electron laser

    SciTech Connect (OSTI)

    Stojanovic, N.; Linde, D. von der; Sokolowski-Tinten, K.; Zastrau, U.; Perner, F.; Foerster, E.; Sobierajski, R.; Nietubyc, R.; Jurek, M.; Klinger, D.; Pelka, J.; Krzywinski, J.; Juha, L; Cihelka, J.; Velyhan, A.; Koptyaev, S.; Hajkova, V.; Chalupsky, J.; Kuba, J.; Tschentscher, T. [Institut fuer Experimentelle Physik, Universitaet Duisburg-Essen, Lotharstrasse 1, 47048 Duisburg (Germany); Institut fuer Optik und Quantenelektronik, FSU Jena, 07743 Jena (Germany); Institute of Physics, PAS, Al. Lotnikov 32/46, 02-668 Warsaw (Poland); Institute of Physics, ASCR, 182 21 Prague (Czech Republic); Czech Technical University, 115 19 Prague (Czech Republic); Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22605 Hamburg (Germany)] (and others)

    2006-12-11T23:59:59.000Z

    The ablation of solids by high energy femtosecond pulses from an extreme ultraviolet (XUV) free electron laser has been investigated using picosecond optical imaging. The time-resolved measurements are supplemented by an analysis of the permanent structural surface modifications. Compared with femtosecond optical excitation, distinct differences in the material response are found which are attributed to the increased penetration depth of the XUV radiation and the absence of any absorption nonlinearities.

  2. Nuclear Instruments and Methods in Physics Research A 528 (2004) 1518 First lasing at the high-power free electron laser at Siberian

    E-Print Network [OSTI]

    Kozak, Victor R.

    2004-01-01T23:59:59.000Z

    -power free electron laser at Siberian center for photochemistry research E.A. Antokhin, R.R. Akberdin, V in April 2003 on a high-power free electron laser (FEL) constructed at the Siberian Center. 2. Accelerator­recuperator Full-scale Novosibirsk free electron laser is to be based on multi

  3. Vol. 6, No. 5/May 1989/J. Opt. Soc. Am. B 977 Application of a two-color free-electron laser to

    E-Print Network [OSTI]

    Fayer, Michael D.

    Vol. 6, No. 5/May 1989/J. Opt. Soc. Am. B 977 Application of a two-color free-electron laser, 1989 The possible applications of a free-electron laser (FEL), which would be modified to produce two of conversations with H. A.Schwettman and T. I. Smith, wediscussed the possible uses of free-electron lasers (FEL

  4. International Congeress on Plasma Physics, Nice, France, 25-29 October 2004 Chaotic particle dynamics in free-electron lasers with coaxial wiggler

    E-Print Network [OSTI]

    Boyer, Edmond

    dynamics in free-electron lasers with coaxial wiggler B. Farokhi and S. Mobarakabadi Islamic Azad University of Arak, Arak, Iran The motion of a relativistic test electron in a free-electron laser orbits. Earlier investigations of chaos in free ­ electron lasers have focused on chaotic behavior

  5. Few-Photon Multiple Ionization of Ne and Ar by Strong Free-Electron-Laser Pulses

    SciTech Connect (OSTI)

    Moshammer, R.; Jiang, Y. H.; Rudenko, A.; Ergler, Th.; Schroeter, C. D.; Luedemann, S.; Zrost, K.; Dorn, A.; Ferger, T.; Kuehnel, K. U.; Ullrich, J. [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); Foucar, L.; Titze, J.; Jahnke, T.; Schoeffler, M.; Doerner, R. [Institut fuer Kernphysik, Universitaet Frankfurt, D 60486 Frankfurt (Germany); Fischer, D. [Atomic Physics, Stockholm University, Alba Nova University Centrum, 10691 Stockholm (Sweden); Weber, T. [Institut fuer Kernphysik, Universitaet Frankfurt, D 60486 Frankfurt (Germany); DESY, Notkestrasse 85, 22607 Hamburg (Germany); Zouros, T. J. M. [Department of Physics, University of Crete, P.O. Box 2208, 71003 Heraklion, Crete (Greece); Institute of Electronic Structure and Laser, P.O. Box 1527, 71110 Heraklion, Crete (Greece); Duesterer, S. [DESY, Notkestrasse 85, 22607 Hamburg (Germany)] (and others)

    2007-05-18T23:59:59.000Z

    Few-photon multiple ionization of Ne and Ar atoms by strong vacuum ultraviolet laser pulses from the free-electron laser at Hamburg was investigated differentially with the Heidelberg reaction microscope. The light-intensity dependence of Ne{sup 2+} production reveals the dominance of nonsequential two-photon double ionization at intensities of I<6x10{sup 12} W/cm{sup 2} and significant contributions of three-photon ionization as I increases. Ne{sup 2+} recoil-ion-momentum distributions suggest that two electrons absorbing ''instantaneously'' two photons are ejected most likely into opposite hemispheres with similar energies.

  6. First Observation of Self-Amplified Spontaneous Emission in a Free-Electron Laser at 109 nm Wavelength

    E-Print Network [OSTI]

    Andruszków, J; Ayvazyan, V T; Baboi, N I; Bakker, R; Balakin, V; Barni, D; Bazhan, A; Bernard, M; Bosotti, A; Bourdon, J C; Brefeld, W; Brinkmann, R; Bühler, S; Carneiro, J P; Castellano, M G; Castro, P; Catani, L; Chel, S; Cho, Y; Choroba, S; Colby, E R; Decking, W; Den Hartog, P; Desmons, M; Dohlus, M; Edwards, D; Edwards, H T; Faatz, B; Feldhaus, J; Ferrario, M; Fitch, M J; Flöttmann, K; Fouaidy, M; Gamp, A; Garvey, Terence; Geitz, M A; Gluskin, E S; Gretchko, V; Hahn, U; Hartung, W H; Hubert, D; Hüning, M; Ischebek, R; Jablonka, M; Joly, J M; Juillard, M; Junquera, T; Jurkiewicz, P; Kabel, A C; Kahl, J; Kaiser, H; Kamps, T; Katelev, V V; Kirchgessner, J L; Körfer, M; Kravchuk, L V; Kreps, G; Krzywinski, J; Lokajczyk, T; Lange, R; Leblond, B; Leenen, M; Lesrel, J; Liepe, M; Liero, A; Limberg, T; Lorenz, R; Lu, H H; Lu, F H; Magne, C; Maslov, M A; Materlik, G; Matheisen, A; Menzel, J; Michelato, P; Möller, W D; Mosnier, A; Müller, U C; Napoly, O; Novokhatskii, A V; Omeich, M; Padamsee, H; Pagani, C; Peters, F; Petersen, B; Pierini, P; Pflüger, J; Piot, P; Phung Ngoc, B; Plucinski, L; Proch, D; Rehlich, K; Reiche, S; Reschke, D; Reyzl, I; Rosenzweig, J; Rossbach, J; Roth, S; Saldin, E L; Sandner, W; Sanok, Z; Schlarb, H; Schmidt, G; Schmüser, P; Schneider, J R; Schneidmiller, E A; Schreiber, H J; Schreiber, S; Schütt, P; Sekutowicz, J; Serafini, L; Sertore, D; Setzer, S; Simrock, S; Sonntag, B F; Sparr, B; Stephan, F; Sytchev, V V; Tazzari, S; Tazzioli, F; Tigner, Maury; Timm, M; Tonutti, M; Trakhtenberg, E; Treusch, R; Trines, D; Verzilov, V A; Vielitz, T; Vogel, V; Von Walter, G; Wanzenberg, R; Weiland, T; Weise, H; Weisend, J G; Wendt, M; Werner, M; White, M M; Will, I; Wolff, S; Yurkov, M V; Zapfe, K; Zhogolev, P; Zhou, F

    2000-01-01T23:59:59.000Z

    We present the first observation of Self-Amplified Spontaneous Emission (SASE) in a free-electron laser (FEL) in the Vacuum Ultraviolet regime at 109 nm wavelength (11 eV). The observed free-electron laser gain (approx. 3000) and the radiation characteristics, such as dependency on bunch charge, angular distribution, spectral width and intensity fluctuations all corroborate the existing models for SASE FELs.

  7. Induction linac-driven free-electron lasers: Status and future prospects

    SciTech Connect (OSTI)

    Prosnitz, D.

    1987-01-11T23:59:59.000Z

    The high repetition rate and low single-pass gain inherent in an rf-driven Free Electron Laser (FEL) dictate that the laser system be configured as an oscillator. This allows the laser's electric field to build up over many passes around a high Q cavity. By way of contrast, the high-current capability of the Induction Linac (IL) system permits high single-pass optical gain, but the relatively low duty factor precludes oscillator operation; the pulses are neither long enough nor often enough to permit a field to accumulate in a cavity. The IL is thus configured as a MOPA (master oscillator/power amplifier) with a conventional laser serving as the MO. This report concentrates on the status of IL-driven FEL research at LLNL and gives a description of several applications for the high-peak-power radiation produced by an induction linac FEL.

  8. High-gain X-ray free electron laser by beat-wave terahertz undulator

    SciTech Connect (OSTI)

    Chang, Chao; Hei, DongWei [Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi'an City 710024 (China) [Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi'an City 710024 (China); Institute of Energy, Tsinghua University, Beijing 100084 (China); Pellegrin, Claudio; Tantawi, Sami [SLAC National Accelerator Laboratory, Stanford University, Stanford, California 94309 (United States)] [SLAC National Accelerator Laboratory, Stanford University, Stanford, California 94309 (United States)

    2013-12-15T23:59:59.000Z

    The THz undulator has a higher gain to realize a much brighter X-ray at saturation, compared with the optical undulator under the same undulator strength and beam quality. In order to fill the high-power THz gap and realize the THz undulator, two superimposed laser pulses at normal incidence to the electron-beam moving direction form an equivalent high-field THz undulator by the frequency difference to realize the high-gain X-ray Free electron laser. The pulse front tilt of lateral fed lasers is used to realize the electron-laser synchronic interaction. By PIC simulation, a higher gain and a larger X-ray radiation power by the beat wave THz undulator could be realized, compared with the optical undulator for the same electron beam parameters.

  9. Nuclear Instruments and Methods in Physics Research A 407 (1998) 34--39 Ginzburg--Landau model for a free-electron laser

    E-Print Network [OSTI]

    Ng, Chung-Sang

    1998-01-01T23:59:59.000Z

    for a free-electron laser: from single mode to spikes C.S. Ng*, A. Bhattacharjee Department of Physics rights reserved. The possibility that a free-electron laser (FEL) can produce a powerful and coherent and Astronomy, The University of Iowa, Iowa City, IA 52242, USA Abstract Single-mode operation of a free-electron

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

    SciTech Connect (OSTI)

    Hattne, Hattne

    2014-03-04T23:59:59.000Z

    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.

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

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

    Hattne, Hattne

    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.

  12. Threshold conditions for lasing of a free electron laser oscillator with longitudinal electrostatic wiggler

    SciTech Connect (OSTI)

    Sepehri Javan, N. [Department of Physics, Faculty of Sciences, University of Mohaghegh Ardabili, P.O. Box 179, Ardabil, 56199-11367 (Iran, Islamic Republic of)

    2012-12-15T23:59:59.000Z

    The system of the nonlinear non-stationary equations describing spatial-temporal dynamics of the amplitudes of an ondulator radiation and a space-charge wave of a relativistic electron beam in the resonator is obtained. A free electron laser resonator with longitudinal electrostatic wiggler is considered. In the linear approximation, the threshold conditions of lasing for Raman and Compton regimes under excitation of forward and backward electromagnetic wave are achieved. In the various physical situations, the variation of the minimum length of the resonator with the amplitude of wiggler, density of electron beam, and with the reflection coefficients of resonator's mirrors is investigated.

  13. Single-shot measurement of free-electron laser polarization at SDUV-FEL

    E-Print Network [OSTI]

    Feng, Lie; Zhang, Tong; Feng, Chao; Chen, Jianhui; Wang, Xingtao; Lan, Taihe; Shen, Lei; Zhang, Wenyan; Yao, Haifeng; Liu, Xiaoqing; Liu, Bo; Wang, Dong

    2014-01-01T23:59:59.000Z

    In this paper, a division-of-amplitude photopolarimeter (DOAP) for measuring the polarization state of free-electron laser (FEL) pulse is described. The incident FEL beam is divided into four separate beams, and four Stokes parameters can be measured in a single-shot. In the crossed-planar undulators experiment at Shanghai deep ultraviolet FEL test facility, this DOAP instrument constructed in house responses accurately and timely while the polarization-state of fully coherent FEL pulses are switched, which is helpful for confirming the crossed-planar undulators technique for short-wavelength FELs.

  14. Integrated Numerical Experiments (INEX) and the Free-Electron Laser Physical Process Code (FELPPC)

    SciTech Connect (OSTI)

    Thode, L.E.; Chan, K.C.D.; Schmitt, M.J.; McKee, J.; Ostic, J.; Elliott, C.J.; McVey, B.D.

    1990-01-01T23:59:59.000Z

    The strong coupling of subsystem elements, such as the accelerator, wiggler, and optics, greatly complicates the understanding and design of a free electron laser (FEL), even at the conceptual level. Given the requirements for high-performance FELs, the strong coupling between the laser subsystems must be included to obtain a realistic picture of the potential operational capability. To address the strong coupling character of the FEL the concept of an Integrated Numerical Experiment (INEX) was proposed. Unique features of the INEX approach are consistency and numerical equivalence of experimental diagnostics. The equivalent numerical diagnostics mitigates the major problem of misinterpretation that often occurs when theoretical and experimental data are compared. The INEX approach has been applied to a large number of accelerator and FEL experiments. Overall, the agreement between INEX and the experiments is very good. Despite the success of INEX, the approach is difficult to apply to trade-off and initial design studies because of the significant manpower and computational requirements. On the other hand, INEX provides a base from which realistic accelerator, wiggler, and optics models can be developed. The Free Electron Laser Physical Process Code (FELPPC) includes models developed from INEX, provides coupling between the subsystems models and incorporates application models relevant to a specific trade-off or design study.

  15. Strongly aligned gas-phase molecules at Free-Electron Lasers

    E-Print Network [OSTI]

    Kierspel, Thomas; Mullins, Terry; Robinson, Joseph; Aquila, Andy; Barty, Anton; Bean, Richard; Boll, Rebecca; Boutet, Sébastien; Bucksbaum, Philip; Chapman, Henry N; Christensen, Lauge; Fry, Alan; Hunter, Mark; Koglin, Jason E; Liang, Mengning; Mariani, Valerio; Morgan, Andrew; Natan, Adi; Petrovic, Vladimir; Rolles, Daniel; Rudenko, Artem; Schnorr, Kirsten; Stapelfeldt, Henrik; Stern, Stephan; Thøgersen, Jan; Yoon, Chun Hong; Wang, Fenglin; Trippel, Sebastian; Küpper, Jochen

    2015-01-01T23:59:59.000Z

    We demonstrate a novel experimental implementation to strongly align molecules at full repetition rates of free-electron lasers. We utilized the available in-house laser system at the coherent x-ray imaging beamline at the Linac Coherent Light Source. Chirped laser pulses, i. e., the direct output from the regenerative amplifier of the Ti:Sa chirped pulse amplification laser system, were used to strongly align 2,5-diiodothiophene molecules in a molecular beam. The alignment laser pulses had pulse energies of a few mJ and a pulse duration of 94 ps. A degree of alignment of $\\left$ = 0.85 was measured, limited by the intrinsic temperature of the molecular beam rather than by the available laser system. With the general availability of synchronized chirped-pulse-amplified near-infrared laser systems at short-wavelength laser facilities, our approach allows for the universal preparation of molecules tightly fixed in space for experiments with x-ray pulses.

  16. Experimental demonstration of longitudinal beam phase space linearizer in a free-electron laser facility by corrugated structures

    E-Print Network [OSTI]

    Deng, Haixiao; Feng, Chao; Zhang, Tong; Wang, Xingtao; Lan, Taihe; Feng, Lie; Zhang, Wenyan; Liu, Xiaoqing; Yao, Haifeng; Shen, Lei; Li, Bin; Zhang, Junqiang; Li, Xuan; Fang, Wencheng; Wang, Dan; Couprie, Marie-emmanuelle; Lin, Guoqiang; Liu, Bo; Gu, Qiang; Wang, Dong; Zhao, Zhentang

    2014-01-01T23:59:59.000Z

    Removal of residual linear energy chirp and intrinsic nonlinear energy curvature in the relativistic electron beam from radiofrequency linear accelerator is of paramount importance for efficient lasing of a high-gain free-electron laser. Recently, it was theoretically and experimentally demonstrated that the longitudinal wakefield excited by the electrons itself in the corrugated structure allows for precise control of the electron beam phase space. In this Letter, we report the first utilization of a corrugated structure as beam linearizer in the operation of a seeded free-electron laser driven by a 140 MeV linear accelerator, where a gain of ~10,000 over spontaneous emission was achieved at the second harmonic of the 1047 nm seed laser, and a free-electron laser bandwidth narrowing by about 50% was observed, in good agreement with the theoretical expectations.

  17. Ultrafast time dynamics studies of periodic lattices with free electron laser radiation

    SciTech Connect (OSTI)

    Quevedo, W.; Busse, G.; Hallmann, J.; More, R.; Petri, M.; Rajkovic, I. [Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Goettingen (Germany); Krasniqi, F.; Rudenko, A. [Max Planck Advanced Study Group at CFEL, Notkestrasse 85, 22607 Hamburg (Germany); Tschentscher, T. [European XFEL GmbH, Albert-Einstein-Ring 19, 22671 Hamburg (Germany); Stojanovic, N.; Duesterer, S.; Treusch, R.; Tolkiehn, M. [HASYLAB at DESY, Notkestrasse 85, 22607 Hamburg (Germany); Techert, S. [Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Goettingen (Germany); Max Planck Advanced Study Group at CFEL, Notkestrasse 85, 22607 Hamburg (Germany)

    2012-11-01T23:59:59.000Z

    It has been proposed that radiation from free electron laser (FEL) at Hamburg (FLASH) can be used for ultrafast time-resolved x-ray diffraction experiments based on the near-infrared (NIR) pump/FEL probe scheme. Here, investigation probing the ultrafast structural dynamics of periodic nano-crystalline organic matter (silver behenate) with such a scheme is reported. Excitation with a femtosecond NIR laser leads to an ultrafast lattice modification which time evolution has been studied through the scattering of vacuum ultraviolet FEL pulses. The found effect last for 6 ps and underpins the possibility for studying nanoperiodic dynamics down to the FEL source time resolution. Furthermore, the possibility of extending the use of silver behenate (AgBh) as a wavelength and temporal calibration tool for experiments with soft x-ray/FEL sources is suggested.

  18. Overview Of Control System For Jefferson Lab`s High Power Free Electron Laser

    SciTech Connect (OSTI)

    Hofler, A. S.; Grippo, A. C.; Keesee, M. S.; Song, J.

    1997-12-31T23:59:59.000Z

    In this paper the current plans for the control system for Thomas Jefferson National Accelerator Facility`s (Jefferson Lab`s) Infrared Free Electron Laser (FEL) are presented. The goals for the FEL control system are fourfold: (1) to use EPICS and EPICS compatible tools, (2) to use VME and Industry Pack (IPs) interfaces for FEL specific devices such as controls and diagnostics for the drive laser, high power optics, photocathode gun and electron-beam diagnostics, (3) to migrate Continuous Electron Beam Accelerator Facility (CEBAF) technologies to VME when possible, and (4) to use CAMAC solutions for systems that duplicate CEBAF technologies such as RF linacs and DC magnets. This paper will describe the software developed for FEL specific devices and provide an overview of the FEL control system.

  19. Status report on Jefferson Lab`s high-power infrared free-electron laser

    SciTech Connect (OSTI)

    Bohn, C.L. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

    1997-10-01T23:59:59.000Z

    Jefferson Lab is building a free-electron laser to produce tunable, continuous-wave (cw), kW-level light at 3-6 {mu}m wavelength. A superconducting accelerator will drive the laser, and a transport lattice will recirculate the beam back through the accelerator for energy recovery. Space charge in the injector and coherent synchrotron radiation in magnetic bends will be present, and the machine is instrumented to study these phenomena during commissioning. The wiggler and optical cavity are conventional; however, significant analysis and testing was needed to ensure mirror heating at 1 kW of outcoupled power would not impede performance. The FEL is being installed in its own facility, and installation will be finished in Fall 1997. This paper surveys the machine, the status of its construction, and plans for its commissioning.

  20. Start-to-end modelling of a mode-locked optical klystron free electron laser amplifier

    SciTech Connect (OSTI)

    Dunning, D. J.; Thompson, N. R. [University of Strathclyde (SUPA), Glasgow G4 0NG (United Kingdom); ASTeC, Daresbury Laboratory, Warrington WA4 4AD (United Kingdom); Mc Neil, B. W. J. [University of Strathclyde (SUPA), Glasgow G4 0NG (United Kingdom); Williams, P. H. [ASTeC, Daresbury Laboratory, Warrington WA4 4AD (United Kingdom)

    2011-07-15T23:59:59.000Z

    A free electron laser (FEL) in a mode-locked optical klystron (MLOK) configuration is modelled using start-to-end simulations that simulate realistic electron beam acceleration and transport before input into a full three-dimensional FEL simulation code. These simulations demonstrate that the MLOK scheme is compatible with the present generation of radiofrequency accelerator designs. A train of few-optical cycle pulses is predicted with peak powers similar to those of the equivalent conventional FEL amplifier. The role of electron beam energy modulation in these results is explained and the limitations of some simulation codes discussed. It is shown how seeding the FEL interaction using a High Harmonic seed laser can improve the coherence properties of the output.

  1. Reversible electron beam heating for suppression of microbunching instabilities at free-electron lasers

    E-Print Network [OSTI]

    Behrens, Christopher; Xiang, Dao

    2011-01-01T23:59:59.000Z

    The presence of microbunching instabilities due to the compression of high-brightness electron beams at existing and future X-ray free-electron lasers (FELs) results in restrictions on the attainable lasing performance and renders beam imaging with optical transition radiation impossible. The instability can be suppressed by introducing additional energy spread, i.e., "heating" the electron beam, as demonstrated by the successful operation of the laser heater system at the Linac Coherent Light Source. The increased energy spread is typically tolerable for self-amplified spontaneous emission FELs but limits the effectiveness of advanced FEL schemes such as seeding. In this paper, we present a reversible electron beam heating system based on two transverse deflecting radio-frequency structures (TDSs) in front and behind a magnetic bunch compressor chicane. The additional energy spread will be introduced in the first TDS, which suppresses the microbunching instability, and then will be eliminated in the second T...

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

    SciTech Connect (OSTI)

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

    2012-01-06T23:59:59.000Z

    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.

  3. PHYSICAL REVIEW A 87, 023407 (2013) Multiphoton above-threshold ionization in superintense free-electron x-ray laser fields

    E-Print Network [OSTI]

    Chu, Shih-I

    2013-01-01T23:59:59.000Z

    . INTRODUCTION With the recent development of free-electron lasers (FELs), particularly the "fourthPHYSICAL REVIEW A 87, 023407 (2013) Multiphoton above-threshold ionization in superintense free-electron successfully used to investigate the multiphoton processes of a hydrogen atom exposed to superintense free-electron

  4. Experimental and theoretical study of free-free electron-helium scattering in a CO2 laser field

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Experimental and theoretical study of free-free electron-helium scattering in a CO2 laser field D.1088/0953-4075/43/2/025203 #12;Free-free e- ­He scattering 2 1. Introduction Laser assisted electron-atom scattering has been.fr Abstract. Free-free transitions during the scattering of electrons by helium in the presence

  5. Multipurpose modular experimental station for the DiProI beamline of Fermi-Elettra free electron laser

    SciTech Connect (OSTI)

    Pedersoli, Emanuele; Capotondi, Flavio; Cocco, Daniele; Kaulich, Burkhard; Menk, Ralf H.; Locatelli, Andrea; Mentes, Tevfik O.; Spezzani, Carlo; Sandrin, Gilio; Bacescu, Daniel M.; Kiskinova, Maya [Fermi, Elettra Sincrotrone Trieste, SS 14 - km 163.5, 34149 Basovizza, Trieste (Italy); Zangrando, Marco [Fermi, Elettra Sincrotrone Trieste, SS 14 - km 163.5, 34149 Basovizza, Trieste (Italy); IOM CNR, Laboratorio TASC, SS 14 - km 163.5, 34149 Basovizza, Trieste (Italy); Bajt, Sasa; Barthelmess, Miriam [Photon Science, DESY, Notkestrasse 85, 22607 Hamburg (Germany); Barty, Anton; Schulz, Joachim; Gumprecht, Lars [Centre for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg (Germany); Chapman, Henry N. [Centre for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg (Germany); University of Hamburg, Notkestrasse 85, 22607 Hamburg (Germany); Nelson, A. J.; Frank, Matthias [Physical and Life Sciences, LLNL, 7000 East Avenue, Livermore, California 94550 (United States); and others

    2011-04-15T23:59:59.000Z

    We present a compact modular apparatus with a flexible design that will be operated at the DiProI beamline of the Fermi-Elettra free electron laser (FEL) for performing static and time-resolved coherent diffraction imaging experiments, taking advantage of the full coherence and variable polarization of the short seeded FEL pulses. The apparatus has been assembled and the potential of the experimental setup is demonstrated by commissioning tests with coherent synchrotron radiation. This multipurpose experimental station will be open to general users after installation at the Fermi-Elettra free electron laser in 2011.

  6. High-power rf-pulsed modulators for the Los Alamos free-electron laser

    SciTech Connect (OSTI)

    Johnson, W.J.D.; Lynch, M.T.; Tallerico, P.J.; Keffeler, D.R.; Hornkohl, J.O.

    1987-09-01T23:59:59.000Z

    In the rf-driven free-electron laser (FEL) at the Los Alamos National Laboratory, there are two pulsed-power rf modulators as sources for two tandem, side-coupled 20-MeV linear accelerators. The rf power used to control the cavity fields is supplied by two 5.5-MW modulating anode klystrons operating at a center frequency of 1300.2 MHz. The modulation of the 125 kV klystron is achieved by using a triode switch tube that provides a pulse width up to 300 ..mu..s and a pulse repetition rate up to 10 Hz. This paper describes the present configuration of these two duplicate systems and presents plans for meeting the requirements of future rf FEL experiments at Los Alamos. 12 refs., 5 figs.

  7. Spatial and temporal coherence properties of single free-electron laser pulses

    E-Print Network [OSTI]

    Singer, A; Mancuso, A P; Gerasimova, N; Yefanov, O M; Gulden, J; Gorniak, T; Senkbeil, T; Sakdinawat, A; Liu, Y; Attwood, D; Dziarzhytski, S; Mai, D D; Treusch, R; Weckert, E; Salditt, T; Rosenhahn, A; Wurth, W; Vartanyants, I A

    2015-01-01T23:59:59.000Z

    The experimental characterization of the spatial and temporal coherence properties of the free-electron laser in Hamburg (FLASH) at a wavelength of 8.0 nm is presented. Double pinhole diffraction patterns of single femtosecond pulses focused to a size of about 10 microns by 10 microns were measured. A transverse coherence length of 6.2 microns in the horizontal and 8.7 microns in the vertical direction was determined from the most coherent pulses. Using a split and delay unit the coherence time of the pulses produced in the same operation conditions of FLASH was measured to be 1.75 fs. From our experiment we estimated the degeneracy parameter of the FLASH beam to be on the order of $10^{10}$ to $10^{11}$, which exceeds the values of this parameter at any other source in the same energy range by many orders of magnitude.

  8. Single-electron analysis of the space-charge effect in free-electron lasers

    SciTech Connect (OSTI)

    Shih, C.; Yariv, A.

    1980-12-01T23:59:59.000Z

    An exact treatment of the space-charge effect in the single-electron analysis of a free-electron laser is presented to calculate its small-signal gain. With the inclusion of the repulsive force between electrons, it is found that the trajectory of an electron can be solved from a generalized equation which includes a space-charge term. The results show the gain is saturated with decreasing growth rate due to high electron density. The radiation frequency is found to increase with the electron density and approach the value at plasma resonance. The condition ..omega../sub p/L/c=..pi.. clearly defines the boundary between the noninteracting and the collective regime of an electron beam, where w/sub p/ is the plasma frequency, L is the device length, and c is the light velocity in vacuum.

  9. Sensing the wavefront of x-ray free-electron lasers using aerosol spheres

    SciTech Connect (OSTI)

    Loh, N.Duane; Starodub, Dimitri; Lomb, Lukas; Hampton, Christina Y.; Martin, Andrew V.; Sierra, Raymond G.; Barty, Anton; Aquila, Andrew; Schulz, Joachim; Steinbrener, Jan; Shoeman, Robert L.; Kassemeyer, Stephan; Bostedt, Christoph; Bozek, John; Epp, Sascha W.; Erk, Benjamin; Hartmann, Robert; Rolles, Daniel; Rudenko, Artem; Rudek, Benedikt; Foucar, Lutz

    2014-04-22T23:59:59.000Z

    Characterizing intense, focused x-ray free electron laser (FEL) pulses is crucial for their use in diffractive imaging. We describe how the distribution of average phase tilts and intensities on hard x-ray pulses with peak intensities of 10 21 W/m2 can be retrieved from an ensemble of diffraction patterns produced by 70 nm-radius polystyrene spheres, in a manner that mimics wave-front sensors. Besides showing that an adaptive geometric correction may be necessary for diffraction data from randomly injected sample sources, the paper demonstrates the possibility of collecting statistics on structured pulses using only the diffraction patterns they generate and highlights the imperative to study its impact on single-particle diffractive imaging.

  10. Diffusion, convection, and solidification in cw-mode free electron laser nitrided titanium

    SciTech Connect (OSTI)

    Hoeche, Daniel; Mueller, Sven [II. Physikalisches Institut, Universitaet Goettingen, Friedrich-Hund-Platz 1, 37077 Goettingen (Germany); Shinn, Michelle [Free Electron Laser Group, Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606 (United States); Schaaf, Peter [Institut fuer Werkstofftechnik, FG Werkstoffe der Elektrotechnik, TU Ilmenau, Postfach 10 05 65, 98684 Ilmenau (Germany)

    2009-04-15T23:59:59.000Z

    Titanium sheets were irradiated by free electron laser radiation in cw mode in pure nitrogen. Due to the interaction, nitrogen diffusion occurs and titanium nitride was synthesized in the tracks. Overlapping tracks have been utilized to create coatings in order to improve the tribological properties of the sheets. Caused by the local heating and the spatial dimension of the melt pool, convection effects were observed and related to the track properties. Stress, hardness, and nitrogen content were investigated with x-ray diffraction, nanoindention, and resonant nuclear reaction analysis. The measured results were correlated with the scan parameters, especially to the lateral track shift. Cross section micrographs were prepared and investigated by means of scanning electron microscopy. They show the solidification behavior, phase formation, and the nitrogen distribution. The experiments give an insight into the possibilities of materials processing using such a unique heat source.

  11. Relativistic X-Ray Free Electron Lasers in the Quantum Regime

    E-Print Network [OSTI]

    Bengt Eliasson; Padma Kant Shukla

    2012-03-02T23:59:59.000Z

    We present a nonlinear theory for relativistic X-ray free electron lasers in the quantum regime, using a collective Klein-Gordon (KG) equation (for relativistic electrons), which is coupled with the Maxwell-Poisson equations for the electromagnetic and electrostatic fields. In our model, an intense electromagnetic wave is used as a wiggler which interacts with a relativistic electron beam to produce coherent tunable radiation. The KG-Maxwell-Poisson model is used to derive a general nonlinear dispersion relation for parametric instabilities in three-space-dimensions, including an arbitrarily large amplitude electromagnetic wiggler field. The nonlinear dispersion relation reveals the importance of quantum recoil effects and oblique scattering of the radiation that can be tuned by varying the beam energy.

  12. The TeraFERMI terahertz source at the seeded FERMI free-electron-laser facility

    SciTech Connect (OSTI)

    Perucchi, A. [Sincrotrone Trieste S.C.p.A., Area Science Park, I-34012 Basovizza, Trieste (Italy); INSTM UdR Trieste-ST, Area Science Park, I-34012 Basovizza, Trieste (Italy); Di Mitri, S.; Penco, G.; Allaria, E. [Sincrotrone Trieste S.C.p.A., Area Science Park, I-34012 Basovizza, Trieste (Italy); Lupi, S. [CNR-IOM and Dipartimento di Fisica, Universita di Roma 'La Sapienza', P.le Aldo Moro 2, I-00185 Roma (Italy)

    2013-02-15T23:59:59.000Z

    We describe the project for the construction of a terahertz (THz) beamline to be called TeraFERMI at the seeded FERMI free electron laser (FEL) facility in Trieste, Italy. We discuss topics as the underlying scientific case, the choice of the source, the expected performance, and THz beam propagation. Through electron beam dynamics simulations we show that the installation of the THz source in the beam dump section provides a new approach for compressing the electron bunch length without affecting FEL operation. Thanks to this further compression of the FEL electron bunch, the TeraFERMI facility is expected to provide THz pulses with energies up to the mJ range during normal FEL operation.

  13. Chaos in an ion-channel free-electron laser with realistic helical wiggler

    SciTech Connect (OSTI)

    Esmaeilzadeh, Mahdi [Department of Physics, Iran University of Science and Technology, Narmak, Tehran 16844 (Iran, Islamic Republic of); Taghavi, Amin [Department of Applied Science, Qaemshahr Branch, Islamic Azad University, Qaemshahr (Iran, Islamic Republic of)

    2012-11-15T23:59:59.000Z

    Chaotic behavior of an electron motion in a free-electron laser with realistic helical wiggler and ion-channel guiding is studied using Poincare surface-of-section maps. The effects of a realistic electron beam density on chaotic electron dynamics are investigated by considering an electron beam with Gaussian density profile in radial distance. The effects of self-fields on chaotic electron dynamics are investigated for different Gaussian beam parameters, and the results are compared with those of uniform electron beam. It is shown that the electron chaotic behavior can be controlled by changing the Gaussian beam parameter. Also, the chaotic behavior can be controlled by increasing the ion-channel and/or the electron beam densities.

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

    SciTech Connect (OSTI)

    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

    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.

  15. Standing-Wave Free-Electron Laser Two-Beam Accelerator

    SciTech Connect (OSTI)

    Sessler, Andrew M.; Whittum, D.H.; Wurtele, Jonathan S.; Sharp, W.M.; Makowski, M.A.

    1991-02-01T23:59:59.000Z

    A free-electron laser (FEL) two-beam accelerator (TBA) is proposed, in which the FEL interaction takes place in a series of drive cavities, rather than in a waveguide. Each drive cavity is 'beat-coupled' to a section of the accelerating structure. This standing-wave TBA is investigated theoretically and numerically, with analyses included of microwave extraction, growth of the FEL signal through saturation, equilibrium longitudinal beam dynamics following saturation, and sensitivity of the microwave amplitude and phase to errors in current and energy. It is found that phase errors due to current jitter are substantially reduced from previous versions of the TBA. Analytic scalings and numerical simulations are used to obtain an illustrative TBA parameter set.

  16. Ultrafast myoglobin structural dynamics observed with an X-ray free-electron laser

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

    Levantino, Matteo; Schirò, Giorgio; Lemke, Henrik Till; Cottone, Grazia; Glownia, James Michael; Zhu, Diling; Chollet, Mathieu; Ihee, Hyotcherl; Cupane, Antonio; Cammarata, Marco

    2015-04-02T23:59:59.000Z

    Light absorption can trigger biologically relevant protein conformational changes. The light induced structural rearrangement at the level of a photoexcited chromophore is known to occur in the femtosecond timescale and is expected to propagate through the protein as a quake-like intramolecular motion. Here we report direct experimental evidence of such ‘proteinquake’ observed in myoglobin through femtosecond X-ray solution scattering measurements performed at the Linac Coherent Light Source X-ray free-electron laser. An ultrafast increase of myoglobin radius of gyration occurs within 1 picosecond and is followed by a delayed protein expansion. As the system approaches equilibrium it undergoes damped oscillations withmore »a ~3.6-picosecond time period. Our results unambiguously show how initially localized chemical changes can propagate at the level of the global protein conformation in the picosecond timescale.« less

  17. Applications of free electron lasers and synchrotrons in industry and research

    SciTech Connect (OSTI)

    Barletta, William A. [Dept. of Physics, Massachusetts Institute of Technology Cambridge MA (United States)

    2013-04-19T23:59:59.000Z

    Synchrotron radiation sources have had a profound effect on both science and technology from their beginnings decades ago as parasitic operations on accelerators for high energy physics. Now the general area of photon science has opened up new experimental techniques which have become the mainstay tools of materials science, surface physics, protein crystallography, and nanotechnology. With the promise of ultra-bright beams from the latest generation of storage rings and free electron lasers with full coherence, the tools of photon science promise to open a new area of mesoscale science and technology as well as prove to be a disruptive wildcard in the search for sustainable energy technologies. This review will survey a range of applications and explore in greater depth the potential applications to EUV lithography and to technologies for solar energy.

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

    SciTech Connect (OSTI)

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

    1992-07-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

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

    1992-07-01T23:59:59.000Z

    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.

  20. Free-electron laser driven by the LBNL laser-plasma accelerator

    E-Print Network [OSTI]

    Schroeder, C. B.

    2010-01-01T23:59:59.000Z

    generated. The ultra-short laser-plasma accelerated beamsbetween the short- pulse laser generating the electron beamscale laser-plasma accelerator that produces ultra-short (

  1. Design of a free-electron laser driven by the LBNL laser-plasma-accelerator

    E-Print Network [OSTI]

    2008-01-01T23:59:59.000Z

    plasma accelerator at the LBNL LOASIS facility”, in: Proc.electron laser driven by the LBNL laser-plasma-accelerator ?National Laboratory (LBNL) laser-plasma accelerator, whose

  2. Free-electron laser driven by the LBNL laser-plasma accelerator

    E-Print Network [OSTI]

    Schroeder, C. B.

    2010-01-01T23:59:59.000Z

    XPLOTGIN, Technical Report LBNL-49625, Lawrence BerkeleyLASER-PLASMA ACCELERATOR AT THE LBNL LOASIS FACILITY,” inelectron laser driven by the LBNL laser-plasma accelerator

  3. Tunable fluid-loaded free-electron laser in the low-electron-energy and long-wavelength extreme R. Drori and E. Jerby*

    E-Print Network [OSTI]

    Jerby, Eli

    Tunable fluid-loaded free-electron laser in the low-electron-energy and long-wavelength extreme R-4 PACS number s : 52.75.Ms, 33.20.Bx, 41.60.Cr, 84.40.Az I. INTRODUCTION In free-electron lasers FELs 1, Tel Aviv University, Ramat Aviv 69978, Israel Received 1 October 1998 A tunable fluid-loaded free-electron

  4. Subnanometer-Scale Measurements of the Interaction of Ultrafast Soft X-Ray Free-Electron-Laser Pulses with Matter

    E-Print Network [OSTI]

    von der Linde, D.

    lengths greater than 3 A° . This experiment demonstrates that with intense ultrafast pulses, structuralSubnanometer-Scale Measurements of the Interaction of Ultrafast Soft X-Ray Free-Electron-Laser Pulses with Matter Stefan P. Hau-Riege,1,* Henry N. Chapman,1 Jacek Krzywinski,2 Ryszard Sobierajski,2

  5. FREE ELECTRON LASERS AND HIGH-ENERGY ELECTRON COOLING* Vladimir N. Litvinenko, BNL, Upton, Long Island, NY, USA#

    E-Print Network [OSTI]

    two orders-of-magnitude. Two techniques offering the potential to cool high- energy hadron beamsFREE ELECTRON LASERS AND HIGH-ENERGY ELECTRON COOLING* Vladimir N. Litvinenko, BNL, Upton, Long Island, NY, USA# Yaroslav S. Derbenev, TJNAF, Newport News, VA, USA) Abstract Cooling intense high

  6. Free-electron laser driven by the LBNL laser-plasma accelerator

    E-Print Network [OSTI]

    Schroeder, C. B.

    2010-01-01T23:59:59.000Z

    kA are generated. The ultra-short laser-plasma acceleratedfree-electron laser (FEL), generating ultra-fast, high-For the ultra-high currents of the laser plasma accelerated

  7. Recirculating accelerator driver for a high-power free-electron laser: A design overview

    SciTech Connect (OSTI)

    Bohn, C.L. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

    1997-06-01T23:59:59.000Z

    Jefferson Lab is building a free-electron laser (FEL) to produce continuous-wave (cw), kW-level light at 3-6 {mu}m wavelength. A superconducting linac will drive the laser, generating a 5 mA average current, 42 MeV energy electron beam. A transport lattice will recirculate the beam back to the linac for deceleration and conversion of about 75% of its power into rf power. Bunch charge will range up to 135 pC, and bunch lengths will range down to 1 ps in parts of the transport lattice. Accordingly, space charge in the injector and coherent synchrotron radiation in magnetic bends come into play. The machine will thus enable studying these phenomena as a precursor to designing compact accelerators of high-brightness beams. The FEL is scheduled to be installed in its own facility by 1 October 1997. Given the short schedule, the machine design is conservative, based on modifications of the CEBAF cryomodule and MIT-Bates transport lattice. This paper surveys the machine design.

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

    SciTech Connect (OSTI)

    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

    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.

  9. Free-electron laser driven by the LBNL laser-plasma accelerator

    E-Print Network [OSTI]

    Schroeder, C. B.

    2010-01-01T23:59:59.000Z

    kA are generated. The ultra-short laser-plasma acceleratedscale laser-plasma accelerator that produces ultra-short (

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

    SciTech Connect (OSTI)

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

    2012-02-15T23:59:59.000Z

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

  11. Slippage effect on energy modulation in seeded free-electron lasers with frequency chirped seed laser pulses

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

    Feng, Chao; Deng, Haixiao; Wang, Guanglei; Wang, Dong; Zhao, Zhentang; Xiang, Dao

    2013-06-01T23:59:59.000Z

    Free-electron lasers (FELs) seeded with external lasers hold great promise for generating high power radiation with nearly transform-limited bandwidth in the soft x-ray region. However, it has been pointed out that the initial seed laser phase error will be amplified by the frequency up-conversion process, which may degrade the quality of the output radiation produced by a harmonic generation scheme. In this paper, theoretical and simulation studies on frequency chirp amplification in seeded FEL schemes with slippage effect taken into account are presented. It is found that the seed laser imperfection experienced by the electron beam can be significantly smoothed by the slippage effect in the modulator when the slippage length is comparable to the seed laser pulse length. This smoothing effect allows one to preserve the excellent temporal coherence of seeded FELs in the presence of large frequency chirp in the seed laser. Our studies show that the tolerance on frequency chirp in the seed laser for generating nearly transform-limited soft x-ray pulses in seeded FELs is much looser than previously thought and fully coherent radiation at nanometer wavelength may be reached with current technologies.

  12. Investigation of the electron trajectories and gain regimes of the whistler pumped free-electron laser

    SciTech Connect (OSTI)

    Jafarinia, F.; Jafari, S. [Department of Physics, University of Guilan, Rasht 41335-1914 (Iran, Islamic Republic of); Mehdian, H. [Department of Physics and Institute for Plasma Research, Tarbiat Moallem University, Tehran 15614 (Iran, Islamic Republic of)

    2013-04-15T23:59:59.000Z

    A free-electron laser (FEL) scheme, which employs the whistler wave as a slow electromagnetic wave wiggler, was studied theoretically. Subjected to the transverse fields of whistler wave wiggler, the beam electrons are the source of the energy needed to produce electromagnetic radiation. The strength and the period of the wiggler field depend on the parameters of the magnetoplasma medium. This configuration has a higher tunability by controlling the plasma density, on top of the {gamma}-tunability of the conventional FELs. The theory of linear gain and electron trajectories was presented and four groups (I, II, III, and IV) of electron orbits were found in the presence of an axial guide magnetic field. Using perturbation analysis, it is found that these groups of orbits were stable except small regions of group I and IV orbits. The function {Phi} which determines the rate of change of axial velocity with beam energy was also derived. In the case in which {Phi}<0 represents a negative-mass regime in which the axial velocity accelerates as the electrons lose energy. Numerical solutions showed that by increasing the cyclotron frequency, the gain for group I and III orbits increased, while a gain decrement was obtained for group II and IV orbits.

  13. Rapid development of a measurement and control system for the Advanced Free-Electron Laser

    SciTech Connect (OSTI)

    Wilson, W.L. Jr.; May, M.W.; Kozubal, A.J.

    1991-01-01T23:59:59.000Z

    The Experimental Physics and Industrial Control System (EPICS) is being used to develop a measurement and control system for the Advanced Free-Electron laser (AFEL) at the Los Alamos National Laboratory. EPICS is an integrated system of applications development tools and a distributed run time environment that supports an input-output database, a graphical operator interface, sequential control through state'' definition, data archiving, data analysis, and fault management. It is very advantageous in terms of both time and system integrity to be able to perform much of the control system development before the actual hardware for the AFEL is in place. Using the EPICS applications tools, we are developing prototype measurements and controls that can be directly transferred to the AFEL during installation and commissioning. This is possible due primarily to three aspects of EPICS. First we can easily model physical systems with the state notation language. Second, we can simulate input and output channels with soft'' database channels, which are created using the database configuration tool. Third, we can easily build and modify operator interface screens with the display editor. 8 refs., 3 figs.

  14. Operational Radiation Protection in Synchrotron Light and Free Electron Laser Facilities

    SciTech Connect (OSTI)

    Liu, James C.; Rokni, Sayed H.; /SLAC; Vylet, Vaclav; /Jefferson Lab

    2009-12-11T23:59:59.000Z

    The 3rd generation synchrotron radiation (SR) facilities are storage ring based facilities with many insertion devices and photon beamlines, and have low injection beam power (< few tens of watts), but extremely high stored beam power ({approx} 1 GW). The 4th generation x-ray free electron laser (FEL) facilities are based on an electron Linac with a long undulator and have high injection beam power (a few kW). Due to its electron and photon beam characteristics and modes of operation, storage ring and photon beamlines have unique safety aspects, which are the main subjects of this paper. The shielding design limits, operational modes, and beam losses are first reviewed. Shielding analysis (source terms and methodologies) and interlocked safety systems for storage ring and photon beamlines (including SR and gas bremsstrahlung) are described. Specific safety issues for storage ring top-off injection operation and FEL facilities are discussed. The operational safety program, e.g., operation authorization, commissioning, training, and radiation measurements, for SR facilities is also presented.

  15. Efficiency enhancement of a two-beam free-electron laser

    SciTech Connect (OSTI)

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

    2009-12-15T23:59:59.000Z

    A local and nonlinear simulation of two-beam and tapered free-electron laser (FEL) is presented self-consistently. The slippage of the electromagnetic wave with respect to the electron beam is ignored and the relativistic electron beams are assumed to be cold. The fundamental resonance and the third harmonic radiation of the beam with lower energy are considered, in which the third harmonic is at the fundamental resonance of the beam with higher energy. The wiggler field is set to decrease linearly when the radiation of the third harmonic saturates. The optimum starting point of tapering and the slope of the reduction in the amplitude of wiggler are found by successive run of the code. Using the slowly varying envelope approximation, a set of nonlinear equations is derived which describes this system. These equations are solved numerically by the Runge-Kutta method. This method can be used to improve the efficiency of the two-beam FEL in the extreme ultraviolet and x-ray regions of spectrum.

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

    E-Print Network [OSTI]

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

    2015-01-01T23:59:59.000Z

    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...

  17. Efficiency enhancement of nonlinear odd harmonics in thermal free electron laser

    SciTech Connect (OSTI)

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

    2013-05-07T23:59:59.000Z

    The effect of axial energy spread on the radiation of third harmonic is studied in the free electron laser with planar wiggler and ion-channel guiding. Spread in the longitudinal momentum and so in the initial energy of electron beam, without any spread in the transverse velocity, is assumed in the form of Gaussian distribution function. The technique that is employed is a one-dimensional and steady-state simulation. A set of self consistent nonlinear differential equations that describes the system is solved numerically by Runge-Kutta method. Due to the sensitivity of harmonics to thermal effects, gain improvement of third harmonic radiation is achieved by using ion-channel guiding technique and efficiency enhancement is applied by tapering the magnetic field of wiggler to optimize radiation. The bunching parameter of the electron beam is also studied. It is found that the growth of the magnitude of the bunching parameter that is caused by the ponderomotive wave stops before the saturation point of the radiation. This means that ponderomotive wave saturates at a shorter distance compared to the radiation.

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

    SciTech Connect (OSTI)

    Vaughan, D. (comp.)

    1992-04-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Vaughan, D. [comp.

    1992-04-01T23:59:59.000Z

    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.

  20. Scaling relations and parameters for 1 Angstrom FEL. [Free Electron Laser

    SciTech Connect (OSTI)

    Yu, L.H.

    1990-01-01T23:59:59.000Z

    The Free Electron Laser (FEL) holds great promise as a tunable source of coherent radiation. At the present, the shortest wavelength achieved by an FEL is 2500 {Angstrom}. However, as recent progress in the development of laser driven photocathode electron guns has provided electron beams with lower and lower emittance and higher and higher current, it has become clear that FEL's with much shorter wavelength can be achieved. An FEL operating below 1000 {Angstrom} will yield important advances in fields such as photochemistry, atomic and molecular physics. An FEL with wavelength of 30 {Angstrom} will bring new era to the development of holography of living cells. And, if an FEL with 1 {Angstrom} wavelength can be developed, its impact on solid physics, molecular biology, and many other fields can hardly be exaggerated. We first describe our electron distribution model: a waterbag transverse phase space distribution and a Gaussian energy distribution. This model is widely used in simulations, and is rather close to reality. Then we describe the dispersion relation derived from the Vlasov-Maxwell equations, and its solution, expressed in scaled form. We compare the variational approximation with several simulation codes. Then we compare with exact results which we have derived for a parallel electron beam with finite beam size and energy spread. We explain the scaling relations, and give examples to show how system parameters scale when the FEL wavelength is reduced. Then, applying these scaling relations, we derive a list of preliminary system parameters for a 1 {Angstrom} FEL. As an example, we apply our analytical calculation to optimize one set of parameters derived from the scaling relations. Finally, as a conclusion we discuss the implication of the list of parameters for a 1{Angstrom} FEL. 20 refs., 4 figs.

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

    SciTech Connect (OSTI)

    Corlett, John; Attwood, David; Byrd, John; Denes, Peter; Falcone, Roger; Heimann, Phil; Leemans, Wim; Padmore, Howard; Prestemon, Soren; Sannibale, Fernando; Schlueter, Ross; Schroeder, Carl; Staples, John; Venturini, Marco; Warwick, Tony; Wells, Russell; Wilcox, Russell; Zholent, Alexander; Adolphsen, Chris; Arthur, John; Bergmann, Uwe; Cai, Yunhai; Colby, Eric; Dowell, David; Emma, Paul; Fox, John; Frisch, Josef; Galayda, John; Hettel, Robert; Huang, Zhirong; Phinney, Nan; Rabedeau, Tom; Raubenheimer, Tor; Reis, David; Schmerge, John; Stöhr, Joachim; Stupakov, Gennady; White, Bill; Xiang, Dao

    2009-06-08T23:59:59.000Z

    Several recent reports have identified the scientific requirements for a future soft x-ray light source, and a high-repetition-rate free-electron laser (FEL) facility that is responsive to these requirements is now on the horizon. R&D in some critical areas is needed, however, to demonstrate technical performance, thus reducing technical risks and construction costs. Such a facility most likely will be based on a CW superconducting linear accelerator with beam supplied by a high-brightness, high-repetition-rate photocathode electron gun operating in CW mode, and on an array of FELs to which the accelerated beam is distributed, each operating at high repetition rate and with even pulse spacing. Dependent on experimental requirements, the individual FELs can be configured for either self-amplified spontaneous emission (SASE), seeded, or oscillator mode of operation, including the use of high-gain harmonic generation (HGHG), echo-enhanced harmonic generation (EEHG), harmonic cascade, or other configurations. In this White Paper we identify the overall accelerator R&D needs, and highlight the most important pre-construction R&D tasks required to value-engineer the design configuration and deliverables for such a facility. In Section 1.4 we identify the comprehensive R&D ultimately needed. We identify below the highest-priority requirements for understanding machine performance and reduce risk and costs at this pre-conceptual design stage. Details of implementing the required tasks will be the subject of future evaluation. Our highest-priority R&D program is the injector, which must be capable of delivering a beam with bunches up to a nanocoulomb at MHz repetition rate and with normalized emittance {le} 1 mm {center_dot} mrad. This will require integrated accelerating structure, cathode, and laser systems development. Cathode materials will impact the choice of laser technology in wavelength and energy per pulse, as well as vacuum requirements in the accelerating structure. Demonstration experiments in advanced seeding techniques, such as EEHG, and other optical manipulations to enhance the FEL process are required to reduce technical risk in producing temporally coherent and ultrashort x-ray output using optical seed lasers. Success of EEHG in particular would result in reduced development and cost of laser systems and accelerator hardware for seeded FELs. With a 1.5-2.5 GeV linac, FELs could operate in the VUV-soft x-ray range, where the actual beam energy will be determined by undulator technology; for example, to use the lower energy would require the use of advanced designs for which undulator R&D is needed. Significant reductions in both unit costs and accelerator costs resulting from the lower electron beam energy required to achieve lasing at a particular wavelength could be obtained with undulator development. Characterization of the wakefields of the vacuum chambers in narrow-gap undulators will be needed to minimize risk in ability to deliver close to transform limited pulses. CW superconducting RF technology for an FEL facility with short bunches at MHz rate and up to mA average current will require selection of design choices in cavity frequency and geometry, higher order mode suppression and power dissipation, RF power supply and distribution, accelerating gradient, and cryogenics systems. R&D is needed to define a cost and performance optimum. Developments in laser technology are proceeding at rapid pace, and progress in high-power lasers, harmonic generation, and tunable sources will need to be tracked.

  2. Synthesis of highly oriented TiN coatings by free electron laser processing of titanium in nitrogen

    SciTech Connect (OSTI)

    Ettore Carpene; Michelle D. Shinn; Peter Schaaf

    2004-11-01T23:59:59.000Z

    Titanium was irradiated in pure nitrogen gas by means of a free electron laser. The treatment resulted in the formation of -TiNx layers, with surface stoichiometry of x {approx} 1. Under certain circumstances the nitride phase showed an almost perfect crystallographic texture with the delta-TiNx(200) planes parallel to the irradiated surface, and well aligned dendrites growing normal to the surface. The mechanism of the dendritic alignment and the origin of the texture correlate with the existence of a solidification front starting at the surface, which is very peculiar for laser surface treatments. This phenomenon is explained with the help of numerical simulations.

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

    E-Print Network [OSTI]

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

    2015-01-01T23:59:59.000Z

    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.

  4. Rontgen-Freie-Elektronen-Laser European XFEL Abbildung 119: Modul Nr. 8 bei der Verladung zum Transport nach Saclay.

    E-Print Network [OSTI]

    , Slowakei, Spanien und Ungarn) auf die Formulierungen der Gr¨undungsdokumente f¨ur den Eu- ropean XFEL verst

  5. Spatio-temporal coherence of free-electron laser radiation in the extreme ultraviolet determined by a Michelson interferometer

    SciTech Connect (OSTI)

    Hilbert, V.; Rödel, C.; Zastrau, U., E-mail: ulf.zastrau@uni-jena.de [Institut für Optik und Quantenelektronik, Friedrich-Schiller-Universität, Max-Wien-Platz 1, 07743 Jena (Germany); Brenner, G.; Düsterer, S.; Dziarzhytski, S.; Harmand, M.; Przystawik, A.; Redlin, H.; Toleikis, S. [Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg (Germany); Döppner, T.; Ma, T. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550 (United States); Fletcher, L. [Department of Physics, University of California, Berkeley, California 94720 (United States); Förster, E. [Institut für Optik und Quantenelektronik, Friedrich-Schiller-Universität, Max-Wien-Platz 1, 07743 Jena (Germany); Helmholtz-Institut Jena, Fröbelstieg 3, 07743 Jena (Germany); Glenzer, S. H.; Lee, H. J. [SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Hartley, N. J. [Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU (United Kingdom); Kazak, L.; Komar, D.; Skruszewicz, S. [Institut für Physik, Universität Rostock, 18051 Rostock (Germany); and others

    2014-09-08T23:59:59.000Z

    A key feature of extreme ultraviolet (XUV) radiation from free-electron lasers (FELs) is its spatial and temporal coherence. We measured the spatio-temporal coherence properties of monochromatized FEL pulses at 13.5?nm using a Michelson interferometer. A temporal coherence time of (59±8) fs has been determined, which is in good agreement with the spectral bandwidth given by the monochromator. Moreover, the spatial coherence in vertical direction amounts to about 15% of the beam diameter and about 12% in horizontal direction. The feasibility of measuring spatio-temporal coherence properties of XUV FEL radiation using interferometric techniques advances machine operation and experimental studies significantly.

  6. Focus characterization at an X-ray free-electron laser by coherent scattering and speckle analysis

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

    Sikorski, Marcin; Song, Sanghoon; Schropp, Andreas; Seiboth, Frank; Feng, Yiping; Alonso-Mori, Roberto; Chollet, Matthieu; Lemke, Henrik T.; Sokaras, Dimosthenis; Weng, Tsu-Chien; et al

    2015-05-01T23:59:59.000Z

    X-ray focus optimization and characterization based on coherent scattering and quantitative speckle size measurements was demonstrated at the Linac Coherent Light Source. Its performance as a single-pulse free-electron laser beam diagnostic was tested for two typical focusing configurations. The results derived from the speckle size/shape analysis show the effectiveness of this technique in finding the focus' location, size and shape. In addition, its single-pulse compatibility enables users to capture pulse-to-pulse fluctuations in focus properties compared with other techniques that require scanning and averaging.

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

    E-Print Network [OSTI]

    Wallis, A O G; Emmanouilidou, A

    2015-01-01T23:59:59.000Z

    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.

  8. A camera for coherent diffractive imaging and holography with a soft-X-ray free electron laser

    SciTech Connect (OSTI)

    Bajt, S; Chapman, H N; Spiller, E; Alameda, J; Woods, B; Frank, M; Bogan, M J; Barty, A; Boutet, S; Marchesini, S; Hau-Riege, S P; Hajdu, J; Shapiro, D

    2007-09-24T23:59:59.000Z

    We describe a camera to record coherent scattering patterns with a soft-X-ray free-electron laser. The camera consists of a laterally-graded multilayer mirror which reflects the diffraction pattern onto a CCD detector. The mirror acts as a bandpass filter both for wavelength and angle, which isolates the desired scattering pattern from non-sample scattering or incoherent emission from the sample. The mirror also solves the particular problem of the extreme intensity of the FEL pulses, which are focused to greater than 10{sup 14} W/cm{sup 2}. The strong undiffracted pulse passes through a hole in the mirror and propagates on to a beam dump at a distance behind the instrument rather than interacting with a beamstop placed near the CCD. The camera concept is extendable for the full range of the fundamental wavelength of the FLASH FEL (i.e. between 6 nm and 60 nm) and into the water window. We have fabricated and tested various multilayer mirrors for wavelengths of 32 nm, 16 nm, 13.5 nm, and 4.5 nm. At the shorter wavelengths mirror roughness must be minimized to reduce scattering from the mirror. We have recorded over 30,000 diffraction patterns at the FLASH free-electron laser with no observable mirror damage or degradation of performance.

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

    E-Print Network [OSTI]

    Staples, John

    2009-01-01T23:59:59.000Z

    Electron Laser Conference, Trieste, Italy (2004) p. 558. 11.Committees of: Sincrotrone Trieste, Italy Pohang Light

  10. Electron bunch energy and phase feed-forward stabilization system for the Mark V RF-linac free-electron laser

    SciTech Connect (OSTI)

    Hadmack, M. R.; Kowalczyk, J. M. D.; Lienert, B. R.; Madey, J. M. J.; Szarmes, E. B. [Department of Physics and Astronomy, University of Hawai'i at Manoa, Honolulu, Hawaii 96822 (United States); Jacobson, B. T. [RadiaBeam Technologies, Santa Monica, California 90404 (United States)

    2013-06-15T23:59:59.000Z

    An amplitude and phase compensation system has been developed and tested at the University of Hawai'i for the optimization of the RF drive system to the Mark V free-electron laser. Temporal uniformity of the RF drive is essential to the generation of an electron beam suitable for optimal free-electron laser performance and the operation of an inverse Compton scattering x-ray source. The design of the RF measurement and compensation system is described in detail and the results of RF phase compensation are presented. Performance of the free-electron laser was evaluated by comparing the measured effects of phase compensation with the results of a computer simulation. Finally, preliminary results are presented for the effects of amplitude compensation on the performance of the complete system.

  11. High-Harmonic Inverse-Free-Electron-Laser Interaction at 800 nm Christopher M. S. Sears, Eric R. Colby, Benjamin M. Cowan, Robert H. Siemann, and James E. Spencer

    E-Print Network [OSTI]

    Byer, Robert L.

    High-Harmonic Inverse-Free-Electron-Laser Interaction at 800 nm Christopher M. S. Sears, Eric R observation of a higher-order inverse-free-electron-laser (IFEL) interaction. Interaction at the fourth, fifth require electron bunches shorter than the laser wavelength. Current rf injectors for linear accelerators

  12. The soft x-ray instrument for materials studies at the linac coherent light source x-ray free-electron laser

    SciTech Connect (OSTI)

    Schlotter, W. F.; Turner, J. J.; Rowen, M.; Holmes, M.; Messerschmidt, M.; Moeller, S.; Krzywinski, J.; Lee, S.; Coffee, R.; Hays, G. [LCLS, SLAC National Accelerator Laboratory, 2575 Sand Hill Rd., Menlo Park, California 94025 (United States); Heimann, P. [LCLS, SLAC National Accelerator Laboratory, 2575 Sand Hill Rd., Menlo Park, California 94025 (United States); Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Krupin, O. [LCLS, SLAC National Accelerator Laboratory, 2575 Sand Hill Rd., Menlo Park, California 94025 (United States); European XFEL GmbH, Albert-Einstein-Ring 19, 22761 Hamburg (Germany); Soufli, R.; Fernandez-Perea, M.; Hau-Riege, S. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550 (United States); Kelez, N. [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Beye, M.; Gerken, N.; Sorgenfrei, F.; Wurth, W. [Institute for Experimental Physics and CFEL, University of Hamburg, Luruper Chaussee 149, 22761 Hamburg (Germany); and others

    2012-04-15T23:59:59.000Z

    The soft x-ray materials science instrument is the second operational beamline at the linac coherent light source x-ray free electron laser. The instrument operates with a photon energy range of 480-2000 eV and features a grating monochromator as well as bendable refocusing mirrors. A broad range of experimental stations may be installed to study diverse scientific topics such as: ultrafast chemistry, surface science, highly correlated electron systems, matter under extreme conditions, and laboratory astrophysics. Preliminary commissioning results are presented including the first soft x-ray single-shot energy spectrum from a free electron laser.

  13. Wiggler, undulator, and free-electron laser-radiation sources development at the National Synchrotron Light Source

    SciTech Connect (OSTI)

    Hsieh, H.; Krinsky, S.; Luccio, A.; Pellegrini, C.; van Steenbergen, A.

    1982-01-01T23:59:59.000Z

    An overview is presented of the special radiation sources development at the NSLS for incorporation in a 2.5 GeV X-ray storage ring and a 700 MeV vuv storage ring. This includes a superconducting high field multipole wiggler, lambda/sub c/ = 0.5A; a permanent magnet wiggler, lambda/sub c/ = 2.0A; a maximum photon energy undulator (5 to 7 keV); an undulator for a soft X-ray line or continuum spectrum and a free electron laser source tunable in the 2500 to 4500A region. Source characteristics and status of development are given. In addition, the incorporation of a backscattered Compton photon source is being studied and relevant parameters are presented.

  14. The Turn-on of LCLS: the X-Ray Free Electron Laser at SLAC ( Keynote - 2011 JGI User Meeting)

    SciTech Connect (OSTI)

    Drell, Persis [SLAC Director] [SLAC Director

    2011-03-22T23:59:59.000Z

    The U.S. Department of Energy Joint Genome Institute (JGI) invited scientists interested in the application of genomics to bioenergy and environmental issues, as well as all current and prospective users and collaborators, to attend the annual DOE JGI Genomics of Energy & Environment Meeting held March 22-24, 2011 in Walnut Creek, Calif. The emphasis of this meeting was on the genomics of renewable energy strategies, carbon cycling, environmental gene discovery, and engineering of fuel-producing organisms. The meeting features presentations by leading scientists advancing these topics. SLAC National Laboratory Director Persis Drell gives a keynote talk on "The Turn-on of LCLS: the X-Ray Free-Electron Laser at SLAC" at the 6th Genomics of Energy & Environment Meeting on March 22, 2011

  15. Statistical mechanics and Vlasov equation allow for a simplified hamiltonian description of single pass free electron laser saturated dynamics

    E-Print Network [OSTI]

    Andrea Antoniazzi; Yves Elskens; Duccio Fanelli; Stefano Ruffo

    2006-01-17T23:59:59.000Z

    A reduced Hamiltonian formulation to reproduce the saturated regime of a single pass free electron laser, around perfect tuning, is here discussed. Asymptotically, $N\\_m$ particles are found to organize in a dense cluster, that evolves as an individual massive unit. The remaining particles fill the surrounding uniform sea, spanning a finite portion of phase space, approximately delimited by the average momenta $\\omega\\_+$ and $\\omega\\_-$. These quantities enter the model as external parameters, which can be self-consistently determined within the proposed theoretical framework. To this aim, we make use of a statistical mechanics treatment of the Vlasov equation, that governs the initial amplification process. Simulations of the reduced dynamics are shown to successfully capture the oscillating regime observed within the original $N$-body picture.

  16. The Turn-on of LCLS: the X-Ray Free Electron Laser at SLAC ( Keynote - 2011 JGI User Meeting)

    ScienceCinema (OSTI)

    Drell, Persis [SLAC Director

    2011-06-08T23:59:59.000Z

    The U.S. Department of Energy Joint Genome Institute (JGI) invited scientists interested in the application of genomics to bioenergy and environmental issues, as well as all current and prospective users and collaborators, to attend the annual DOE JGI Genomics of Energy & Environment Meeting held March 22-24, 2011 in Walnut Creek, Calif. The emphasis of this meeting was on the genomics of renewable energy strategies, carbon cycling, environmental gene discovery, and engineering of fuel-producing organisms. The meeting features presentations by leading scientists advancing these topics. SLAC National Laboratory Director Persis Drell gives a keynote talk on "The Turn-on of LCLS: the X-Ray Free-Electron Laser at SLAC" at the 6th Genomics of Energy & Environment Meeting on March 22, 2011

  17. axial free-electron laser: Topics by E-print Network

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

    but works at shortof the development of electron tubes and atomic lasers. Theyelectron energy and using higher harmonics, and efficiencies of 60% were common. While the Motz...

  18. alamos free-electron laser: Topics by E-print Network

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

    but works at shortof the development of electron tubes and atomic lasers. Theyelectron energy and using higher harmonics, and efficiencies of 60% were common. While the Motz...

  19. Design of a free-electron laser driven by the LBNLlaser-plasma-accelerator

    SciTech Connect (OSTI)

    Schroeder, C.B.; Fawley, W.M.; Montgomery, A.L.; Robinson, K.E.; Gruner, F.; Bakeman, M.; Leemans, W.P.

    2007-09-10T23:59:59.000Z

    We discuss the design and current status of a compactfree-electron laser (FEL), generating ultra-fast, high-peak flux, VUVpulses driven by a high-current, GeV electron beam from the existingLawrence Berkeley National Laboratory (LBNL) laser-plasma accelerator,whose active acceleration length is only a few cm. The proposedultra-fast source would be intrinsically temporally synchronized to thedrive laser pulse, enabling pump-probe studies in ultra-fast science withpulse lengths of tens of fs. Owing to the high current (&10 kA) ofthe laser-plasma-accelerated electron beams, saturated output fluxes arepotentially greater than 1013 photons/pulse. Devices based both on SASEand high-harmonic generated input seeds, to reduce undulator length andfluctuations, are considered.

  20. Absorbed XFEL Dose in the Components of the LCLS X-Ray Optics

    SciTech Connect (OSTI)

    Hau-Riege, Stefan

    2010-12-03T23:59:59.000Z

    There is great concern that the short, intense XFEL pulse of the LCLS will damage the optics that will be placed into the beam. We have analyzed the extent of the problem by considering the anticipated materials and position of the optical components in the beam path, calculated the absorbed dose as a function of photon energy, and compared these doses with the expected doses required (i) to observe rapid degradation due to thermal fatigue, (ii) to reach the melting temperature, or (iii) to actually melt the material. We list the materials that are anticipated to be placed into the Linac Coherent Light Source (LCLS) x-ray free electron laser (XFEL) beam line, their positions, and the absorbed dose, and compare this dose with anticipated damage thresholds.

  1. Cold-target recoil-ion momentum spectroscopy for diagnostics of high harmonics of the extreme-ultraviolet free-electron laser light source at SPring-8

    SciTech Connect (OSTI)

    Liu, X.-J.; Fukuzawa, H.; Pruemper, G.; Ueda, K. [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577 (Japan); RIKEN, XFEL Project Head Office, Kouto 1-1-1, Sayo, Hyogo 679-5148 (Japan); Okunishi, M.; Shimada, K. [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577 (Japan); Motomura, K.; Saito, N. [RIKEN, XFEL Project Head Office, Kouto 1-1-1, Sayo, Hyogo 679-5148 (Japan); National Metrology Institute of Japan, AIST, Tsukuba 305-8568 (Japan); Iwayama, H.; Nagaya, K.; Yao, M. [RIKEN, XFEL Project Head Office, Kouto 1-1-1, Sayo, Hyogo 679-5148 (Japan); Department of Physics, Kyoto University, Kyoto 606-8502 (Japan); Rudenko, A. [RIKEN, XFEL Project Head Office, Kouto 1-1-1, Sayo, Hyogo 679-5148 (Japan); Max Planck Advanced Study Group, CFEL, D-22607, Hamburg (Germany); Ullrich, J. [RIKEN, XFEL Project Head Office, Kouto 1-1-1, Sayo, Hyogo 679-5148 (Japan); Max Planck Advanced Study Group, CFEL, D-22607, Hamburg (Germany); Max Planck-Insitut fuer Kernphysik, D-69117 Heidelberg (Germany); Foucar, L. [RIKEN, XFEL Project Head Office, Kouto 1-1-1, Sayo, Hyogo 679-5148 (Japan); Institut fuer Kernphysik, Universitaet Frankfurt, D-60486 Frankfurt (Germany); Czasch, A.; Schmidt-Boecking, H.; Doerner, R. [Institut fuer Kernphysik, Universitaet Frankfurt, D-60486 Frankfurt (Germany); Nagasono, M.; Higashiya, A.; Yabashi, M. [RIKEN, XFEL Project Head Office, Kouto 1-1-1, Sayo, Hyogo 679-5148 (Japan); and others

    2009-05-15T23:59:59.000Z

    We have developed a cold-target recoil-ion momentum spectroscopy apparatus dedicated to the experiments using the extreme-ultraviolet light pulses at the free-electron laser facility, SPring-8 Compact SASE Source test accelerator, in Japan and used it to measure spatial distributions of fundamental, second, and third harmonics at the end station.

  2. An infrared free electron laser system for the proposed Chemical Dynamics Research Laboratory at LBL based on a 500 MHz superconducting linac

    SciTech Connect (OSTI)

    Kim, K.J.; Byrns, R.; Chattopadhyay, S.; Donahue, R.; Edighoffer, J.; Gough, R.; Hoyer, E.; Leemans, W.; Staples, J.; Taylor, B.; Xie, M.

    1992-09-01T23:59:59.000Z

    We describe a new design of the Infrared Free Electron Laser (IRFEL) for the proposed Chemical Dynamics Research Laboratory (CDRL) at LBL. The design and choice of parameters are dictated by the unique requirements of the CDRL scientific program. The accelerator system is based on the 500 MHz superconducting cavity technology to achieve a wavelength stability of 10{sup {minus}4}.

  3. An infrared free electron laser system for the proposed Chemical Dynamics Research Laboratory at LBL based on a 500 MHz superconducting linac

    SciTech Connect (OSTI)

    Kim, K.J.; Byrns, R.; Chattopadhyay, S.; Donahue, R.; Edighoffer, J.; Gough, R.; Hoyer, E.; Leemans, W.; Staples, J.; Taylor, B.; Xie, M.

    1992-09-01T23:59:59.000Z

    We describe a new design of the Infrared Free Electron Laser (IRFEL) for the proposed Chemical Dynamics Research Laboratory (CDRL) at LBL. The design and choice of parameters are dictated by the unique requirements of the CDRL scientific program. The accelerator system is based on the 500 MHz superconducting cavity technology to achieve a wavelength stability of 10[sup [minus]4].

  4. VISITOR SAFETY TRAINING CHECKLIST: Free Electron Laser (FEL) Laboratory Under California law and campus policy, the University must provide documented safety training for workers.

    E-Print Network [OSTI]

    Ahlers, Guenter

    VISITOR SAFETY TRAINING CHECKLIST: Free Electron Laser (FEL) Laboratory Under California law and campus policy, the University must provide documented safety training for workers. For FEL visitors, this generally means covering the basic guidelines/tasks below. The FEL management loosely defines a "visitor

  5. Invited Article: Coherent imaging using seeded free-electron laser pulses with variable polarization: First results and research opportunities

    SciTech Connect (OSTI)

    Capotondi, F.; Pedersoli, E.; Mahne, N.; Menk, R. H.; Passos, G.; Raimondi, L.; Svetina, C.; Sandrin, G.; Kiskinova, M. [FERMI, Elettra-Sincrotrone Trieste, SS 14 - km 163.5, 34149 Basovizza, Trieste (Italy); Zangrando, M. [FERMI, Elettra-Sincrotrone Trieste, SS 14 - km 163.5, 34149 Basovizza, Trieste (Italy); CNR, Istituto Officina dei Materiali - TASC, SS 14 - km 163.5, 34149 Basovizza, Trieste (Italy); Bajt, S.; Barthelmess, M.; Fleckenstein, H.; Chapman, H. N. [CFEL-DESY, Notkestrasse 85, 22607 Hamburg (Germany); Schulz, J. [European XFEL GmbH, Albert-Einstein-Ring 19, 22761 Hamburg (Germany); Bach, J.; Froemter, R. [Universitaet Hamburg, Institut fuer Angewandte Physik, 20355 Hamburg (Germany); Schleitzer, S.; Mueller, L.; Gutt, C. [DESY, Notkestrasse 85, 22607 Hamburg (Germany); and others

    2013-05-15T23:59:59.000Z

    FERMI-Elettra, the first vacuum ultraviolet and soft X-ray free-electron laser (FEL) using by default a 'seeded' scheme, became operational in 2011 and has been opened to users since December 2012. The parameters of the seeded FERMI FEL pulses and, in particular, the superior control of emitted radiation in terms of spectral purity and stability meet the stringent requirements for single-shot and resonant coherent diffraction imaging (CDI) experiments. The advantages of the intense seeded FERMI pulses with variable polarization have been demonstrated with the first experiments performed using the multipurpose experimental station operated at the diffraction and projection imaging (DiProI) beamline. The results reported here were obtained with fixed non-periodic targets during the commissioning period in 2012 using 20-32 nm wavelength range. They demonstrate that the performance of the FERMI FEL source and the experimental station meets the requirements of CDI, holography, and resonant magnetic scattering in both multi- and single-shot modes. Moreover, we present the first magnetic scattering experiments employing the fully circularly polarized FERMI pulses. The ongoing developments aim at pushing the lateral resolution by using shorter wavelengths provided by double-stage cascaded FERMI FEL-2 and probing ultrafast dynamic processes using different pump-probe schemes, including jitter-free seed laser pump or FEL-pump/FEL-probe with two color FEL pulses generated by the same electron bunch.

  6. Low-Charge, Hard X-Ray Free Electron Laser Driven with an X-Band Injector and Accelerator

    SciTech Connect (OSTI)

    Sun, Yipeng; Adolphsen, Chris; Limborg-Deprey, Cecile; Raubenheimer, Tor; Wu, Juhao; /SLAC

    2012-04-17T23:59:59.000Z

    After the successful operation of the Free Electron Laser in Hamburg (FLASH) and the Linac Coherent Light Source (LCLS), soft and hard x-ray free electron lasers (FELs) are being built, designed, or proposed at many accelerator laboratories. Acceleration employing lower frequency rf cavities, ranging from L-band to C-band, is usually adopted in these designs. In the first stage bunch compression, higher-frequency harmonic rf system is employed to linearize the beam's longitudinal phase space, which is nonlinearly chirped during the lower frequency rf acceleration process. In this paper, a hard x-ray FEL design using an all X-band accelerator at 11.424 GHz (from photocathode rf gun to linac end) is presented, without the assistance of any harmonic rf linearization. It achieves LCLS-like performance at low charge using X-band linac drivers, which is more versatile, efficient, and compact than ones using S-band or C-band rf technology. It employs initially 42 microns long (rms), low-charge (10 pC) electron bunches from an X-band photoinjector. An overall bunch compression ratio of roughly 100 times is proposed in a two stage bunch compressor system. The start-to-end macroparticle 3D simulation employing several computer codes is presented in this paper, where space charge, wakefields, and incoherent and coherent synchrotron radiation effects are included. Employing an undulator with a short period of 1.5 cm, a Genesis FEL simulation shows successful lasing at a wavelength of 0.15 nm with a pulse length of 2 fs and a power saturation length as short as 20 meters, which is equivalent to LCLS low-charge mode. Its overall length of both accelerators and undulators is 180 meters (much shorter than the effective LCLS overall length of 1230 meters, including an accelerator length of 1100 meters and an undulator length of 130 meters), which makes it possible to be built in places where only limited space is available.

  7. Electron beam magnetic switch for a plurality of free electron lasers

    DOE Patents [OSTI]

    Schlitt, Leland G. (Livermore, CA)

    1984-01-01T23:59:59.000Z

    Apparatus for forming and utilizing a sequence of electron beam segments, each of the same temporal length (substantially 15 nsec), with consecutive beams being separated by a constant time interval of the order of 3 nsec. The beam sequence is used for simultaneous inputs to a plurality of wiggler magnet systems that also accept the laser beams to be amplified by interaction with the co-propagating electron beams. The electron beams are arranged substantially in a circle to allow proper distribution of and simultaneous switching out of the beam segments to their respective wiggler magnets.

  8. Development, characterization and experimental performance of x-ray optics for the LCLS free-electron laser

    SciTech Connect (OSTI)

    Soufli, R; Pivovaroff, M J; Baker, S L; Robinson, J C; Gullikson, E M; Mc Carville, T J; Stefan, P M; Aquila, A L; Ayers, J; McKernan, M A; Bionta, R M

    2008-09-10T23:59:59.000Z

    This manuscript discusses the development of reflective optics for the x-ray offset mirror systems of the Linac Coherent Light Source (LCLS), a 0.15-1.5 nm free-electron laser (FEL) at the Stanford Linear Accelerator Center (SLAC). The unique properties (such as the high peak brightness) of the LCLS FEL beam translate to strict limits in terms of materials choice, thus leading to an x-ray mirror design consisting of a reflective coating deposited on a silicon substrate. Furthermore, the physics requirements for these mirrors result in stringent surface figure and finish specifications that challenge the state-of-the-art in x-ray substrate manufacturing, thin film deposition, and metrology capabilities. Recent experimental results on the development, optimization, and characterization of the LCLS soft x-ray mirrors are presented in this manuscript, including: precision surface metrology on the silicon substrates, and the development of boron carbide reflective coatings with reduced stress and thickness variation < 0.14 nm rms across the 175-mm clear aperture area of the LCLS soft x-ray mirrors.

  9. Damage Threshold of Platinum Coating used for Optics for Self-Seeding of Soft X-ray Free Electron Laser

    SciTech Connect (OSTI)

    Krzywinski, Jacek; Cocco, Daniele; Moeller, Stefan; Ratner, Daniel

    2015-01-01T23:59:59.000Z

    We investigated the experimental damage threshold of platinum coating on a silicon substrate illuminated by soft x-ray radiation at grazing incidence angle of 2.1 deg. The coating was the same as the blazed grating used for the soft X-ray self-seeding optics of the Linac Coherent Light Source free electron laser. The irradiation condition was chosen such that the absorbed dose was similar to the maximum dose expected for the grating. The expected dose was simulated by solving the Helmholtz equation in non-homogenous media. The experiment was performed at 900 eV photon energy for both single pulse and multi-shot conditions. We have not observed single shot damage. This corresponds to a single shot damage threshold being higher than 3 J/cm2. The multiple shot damage threshold measured for 10 shots and about 600 shots was determined to be 0.95 J/cm2 and 0.75 J/cm2 respectively. The damage threshold occurred at an instantaneous dose which is higher that the melt dose of platinum.

  10. Damage Threshold of Platinum Coating used for Optics for Self-Seeding of Soft X-ray Free Electron Laser

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

    Krzywinski, Jacek; Cocco, Daniele; Moeller, Stefan; Ratner, Daniel

    2015-01-01T23:59:59.000Z

    We investigated the experimental damage threshold of platinum coating on a silicon substrate illuminated by soft x-ray radiation at grazing incidence angle of 2.1 deg. The coating was the same as the blazed grating used for the soft X-ray self-seeding optics of the Linac Coherent Light Source free electron laser. The irradiation condition was chosen such that the absorbed dose was similar to the maximum dose expected for the grating. The expected dose was simulated by solving the Helmholtz equation in non-homogenous media. The experiment was performed at 900 eV photon energy for both single pulse and multi-shot conditions. Wemore »have not observed single shot damage. This corresponds to a single shot damage threshold being higher than 3 J/cm2. The multiple shot damage threshold measured for 10 shots and about 600 shots was determined to be 0.95 J/cm2 and 0.75 J/cm2 respectively. The damage threshold occurred at an instantaneous dose which is higher that the melt dose of platinum.« less

  11. The photon analysis, delivery, and reduction system at the FERMI-Elettra free electron laser user facility

    SciTech Connect (OSTI)

    Zangrando, M. [Laboratorio TASC INFM-CNR, I-34149 Basovizza, Trieste (Italy); Abrami, A.; Cudin, I.; Fava, C.; Galimberti, A.; Godnig, R.; Giuressi, D.; Rumiz, L.; Sergo, R.; Svetina, C.; Cocco, D. [Sincrotrone Trieste SCpA, I-34149 Basovizza, Trieste (Italy); Bacescu, D. [CELLS-ALBA, E-08290 Cerdanyola del Valles, Barcelona (Spain); Frassetto, F.; Poletto, L. [Laboratorio LUXOR INFM-CNR, I-35131 Padova (Italy)

    2009-11-15T23:59:59.000Z

    The FERMI-Elettra free electron laser (FEL) user facility is currently under construction at the Sincrotrone Trieste laboratory in Trieste (Italy). It will cover the wavelength range from 100 to about 5 nm in the fundamental and 3 or 1 nm using the third harmonic. We report the layout of the photon beam diagnostics section, the radiation transport system to the experimental area, and the photon beam distribution system. Due to the peculiar characteristics of the emitted FEL radiation (high peak power, short pulse length, and statistical variation of the emitted intensity and distribution), the realization of the diagnostics system is particularly challenging. The end users are interested in parameters such as the radiation pulse intensity and spectral distribution, as well as in the possibility to attenuate the intensity. In order to accomplish these tasks, a photon analysis, delivery, and reduction system is now under development and construction and is presented here. This system will work on-line producing pulse-resolved information and will let users keep track of the photon beam parameters during the experiments.

  12. Bent crystal spectrometer for both frequency and wavenumber resolved x-ray scattering at a seeded free-electron laser

    E-Print Network [OSTI]

    Zastrau, Ulf; Foerster, Eckhart; Galtier, Eric Ch; Gamboa, Eliseo; Glenzer, Siegfried H; Heimann, Philipp; Marschner, Heike; Nagler, Bob; Schropp, Andreas; Wehrhan, Ortrud; Lee, Hae Ja

    2014-01-01T23:59:59.000Z

    We present a cylindrically curved GaAs x-ray spectrometer with energy resolution $\\Delta E/E = 1.1\\cdot 10^{-4}$ and wave-number resolution of $\\Delta k/k = 3\\cdot 10^{-3}$, allowing plasmon scattering at the resolution limits of the Linac Coherent Light Source (LCLS) x-ray free-electron laser. It spans scattering wavenumbers of 3.6 to $5.2/$\\AA\\ in 100 separate bins, with only 0.34\\% wavenumber blurring. The dispersion of 0.418~eV/$13.5\\,\\mu$m agrees with predictions within 1.3\\%. The reflection homogeneity over the entire wavenumber range was measured and used to normalize the amplitude of scattering spectra. The proposed spectrometer is superior to a mosaic HAPG spectrometer when the energy resolution needs to be comparable to the LCLS seeded bandwidth of 1~eV and a significant range of wavenumbers must be covered in one exposure.

  13. Bent crystal spectrometer for both frequency and wavenumber resolved x-ray scattering at a seeded free-electron laser

    SciTech Connect (OSTI)

    Zastrau, Ulf, E-mail: ulf.zastrau@uni-jena.de [Institute of Optics and Quantum Electronics, Friedrich-Schiller University Jena, Max-Wien-Platz 1, 07743 Jena (Germany); Stanford Linear Accelerator Center (SLAC), 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Fletcher, Luke B.; Galtier, Eric Ch.; Gamboa, Eliseo; Glenzer, Siegfried H.; Heimann, Philipp; Nagler, Bob; Schropp, Andreas; Lee, Hae Ja [Stanford Linear Accelerator Center (SLAC), 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Förster, Eckhart [Institute of Optics and Quantum Electronics, Friedrich-Schiller University Jena, Max-Wien-Platz 1, 07743 Jena (Germany); Helmholtz Institute Jena, Fröbelstieg 3, 07743 Jena (Germany); Marschner, Heike; Wehrhan, Ortrud [Institute of Optics and Quantum Electronics, Friedrich-Schiller University Jena, Max-Wien-Platz 1, 07743 Jena (Germany)

    2014-09-15T23:59:59.000Z

    We present a cylindrically curved GaAs x-ray spectrometer with energy resolution ?E/E = 1.1 ×?10{sup ?4} and wave-number resolution of ?k/k = 3 ×?10{sup ?3}, allowing plasmon scattering at the resolution limits of the Linac Coherent Light Source (LCLS) x-ray free-electron laser. It spans scattering wavenumbers of 3.6 to 5.2/Å in 100 separate bins, with only 0.34% wavenumber blurring. The dispersion of 0.418 eV/13.5??m agrees with predictions within 1.3%. The reflection homogeneity over the entire wavenumber range was measured and used to normalize the amplitude of scattering spectra. The proposed spectrometer is superior to a mosaic highly annealed pyrolytic graphite spectrometer when the energy resolution needs to be comparable to the LCLS seeded bandwidth of 1 eV and a significant range of wavenumbers must be covered in one exposure.

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

    SciTech Connect (OSTI)

    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

    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.

  15. Damage Threshold of Platinum Coating used for Optics for Self-Seeding of Soft X-ray Free Electron Laser

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

    Krzywinski, Jacek; Cocco, Daniele; Moeller, Stefan; Ratner, Daniel

    2015-01-01T23:59:59.000Z

    We investigated the experimental damage threshold of platinum coating on a silicon substrate illuminated by soft x-ray radiation at grazing incidence angle of 2.1 deg. The coating was the same as the blazed grating used for the soft X-ray self-seeding optics of the Linac Coherent Light Source free electron laser. The irradiation condition was chosen such that the absorbed dose was similar to the maximum dose expected for the grating. The expected dose was simulated by solving the Helmholtz equation in non-homogenous media. The experiment was performed at 900 eV photon energy for both single pulse and multi-shot conditions. We have not observed single shot damage. This corresponds to a single shot damage threshold being higher than 3 J/cm2. The multiple shot damage threshold measured for 10 shots and about 600 shots was determined to be 0.95 J/cm2 and 0.75 J/cm2 respectively. The damage threshold occurred at an instantaneous dose which is higher that the melt dose of platinum.

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

    SciTech Connect (OSTI)

    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

    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.

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

    SciTech Connect (OSTI)

    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

    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.

  18. 9/16/11 11:18 PMAPS -53rd Annual Meeting of the APS Division of Plasma Physics -Event ...stler amplification: a free electron laser in the Earth's magnetosphere Page 1 of 2http://meetings.aps.org/Meeting/DPP11/Event/153292

    E-Print Network [OSTI]

    Ng, Chung-Sang

    amplification: a free electron laser in the Earth's magnetosphere Page 1 of 2http amplification: a free electron laser in the Earth's magnetosphere 4:24 PM­4:36 PM Preview Abstract Authors: A of the whistler wave. Based on the similarities between free electron lasers (FELs) and whistler mode emissions

  19. Improved crystal orientation and physical properties from single-shot XFEL stills

    SciTech Connect (OSTI)

    Sauter, Nicholas K., E-mail: nksauter@lbl.gov; Hattne, Johan; Brewster, Aaron S.; Echols, Nathaniel; Zwart, Petrus H.; Adams, Paul D. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

    2014-12-01T23:59:59.000Z

    X-ray free-electron laser crystallography relies on the collection of still-shot diffraction patterns. New methods are developed for optimal modeling of the crystals’ orientations and mosaic block properties. X-ray diffraction patterns from still crystals are inherently difficult to process because the crystal orientation is not uniquely determined by measuring the Bragg spot positions. Only one of the three rotational degrees of freedom is directly coupled to spot positions; the other two rotations move Bragg spots in and out of the reflecting condition but do not change the direction of the diffracted rays. This hinders the ability to recover accurate structure factors from experiments that are dependent on single-shot exposures, such as femtosecond diffract-and-destroy protocols at X-ray free-electron lasers (XFELs). Here, additional methods are introduced to optimally model the diffraction. The best orientation is obtained by requiring, for the brightest observed spots, that each reciprocal-lattice point be placed into the exact reflecting condition implied by Bragg’s law with a minimal rotation. This approach reduces the experimental uncertainties in noisy XFEL data, improving the crystallographic R factors and sharpening anomalous differences that are near the level of the noise.

  20. Damage threshold and focusability of mid-infrared free-electron laser pulses gated by a plasma mirror with nanosecond switching pulses

    SciTech Connect (OSTI)

    Wang, Xiaolong; Nakajima, Takashi; Zen, Heishun; Kii, Toshiteru; Ohgaki, Hideaki [Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan)] [Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan)

    2013-11-04T23:59:59.000Z

    The presence of a pulse train structure of an oscillator-type free-electron laser (FEL) results in the immediate damage of a solid target upon focusing. We demonstrate that the laser-induced damage threshold can be significantly improved by gating the mid-infrared FEL pulses with a plasma mirror. Although the switching pulses we employ have a nanosecond duration which does not guarantee the clean wavefront of the gated FEL pulses, the high focusability is experimentally confirmed through the observation of spectral broadening by a factor of 2.1 when we tightly focus the gated FEL pulses onto the Ge plate.

  1. The FERMI@Elettra free-electron-laser source for coherent X-ray physics: photon properties, beam transport system, and applications

    E-Print Network [OSTI]

    Allaria, Enrico

    2010-01-01T23:59:59.000Z

    49625-Rev. 1 (also SLAC Rpt. LCLS-TN-04-3) Fawley W M 2006wavelength FELs (e.g. , FLASH, LCLS, SCSS, XFEL, SPARX) have

  2. Comment on “Competition between coherent emission and broadband spontaneous emission in the quantum free electron laser” [Phys. Plasmas 20, 033106 (2013)

    SciTech Connect (OSTI)

    Petrillo, V.; Rossi, A. R.; Serafini, L. [Università di Milano-INFN, Via Celoria, 16 Milano (Italy)] [Università di Milano-INFN, Via Celoria, 16 Milano (Italy)

    2013-12-15T23:59:59.000Z

    We point out that in the equation for the electron distribution evolution during Thomson/Compton or undulator radiation used in the paper: “Competition between coherent emission and broadband spontaneous emission in the quantum free electron laser” by G. R. M. Robb and R. Bonifacio [Phys. Plasmas 20, 033106 (2013)], the weight function should be the distribution of the number of emitted photons and not the photon energy distribution. Nevertheless, the considerations expressed in this comment do not alter the conclusions drawn in the paper in object.

  3. Wavefront Analysis of Nonlinear Self-Amplified Spontaneous-Emission Free-Electron Laser Harmonics in the Single-Shot Regime

    SciTech Connect (OSTI)

    Bachelard, R.; Chubar, O.; Mercere, P.; Idir, M.; Couprie, M.E.; Lambert, G.; Zeitoun, Ph.; Kimura, H.; Ohashi, H.; Higashiya, A.; Yabashi, M.; Nagasono, M.; Hara, T. and Ishikawa, T.

    2011-06-08T23:59:59.000Z

    The single-shot spatial characteristics of the vacuum ultraviolet self-amplified spontaneous emission of a free electron laser (FEL) is measured at different stages of amplification up to saturation with a Hartmann wavefront sensor. We show that the fundamental radiation at 61.5 nm tends towards a single-mode behavior as getting closer to saturation. The measurements are found in good agreement with simulations and theory. A near diffraction limited wavefront was measured. The analysis of Fresnel diffraction through the Hartmann wavefront sensor hole array also provides some further insight for the evaluation of the FEL transverse coherence, of high importance for various applications.

  4. The FERMI@Elettra free-electron-laser source for coherent X-ray physics: photon properties, beam transport system, and applications

    SciTech Connect (OSTI)

    Allaria, Enrico; Callegari, Carlo; Cocco, Daniele; Fawley, William M.; Kiskinova, Maya; Masciovecchio, Claudio; Parmigiani, Fulvio

    2010-04-05T23:59:59.000Z

    FERMI@Elettra is comprised of two free electron lasers (FELs) that will generate short pulses (tau ~;; 25 to 200 fs) of highly coherent radiation in the XUV and soft X-ray region. The use of external laser seeding together with a harmonic upshift scheme to obtain short wavelengths will give FERMI@Elettra the capability to produce high quality, longitudinal coherent photon pulses. This capability together with the possibilities of temporal synchronization to external lasers and control of the output photon polarization will open new experimental opportunities not possible with currently available FELs. Here we report on the predicted radiation coherence properties and important configuration details of the photon beam transport system. We discuss the several experimental stations that will be available during initial operations in 2011, and we give a scientific perspective on possible experiments that can exploit the critical parameters of this new light source.

  5. Study of an HHG-Seeded Free-Electron Laser for the LBNL Next Generation Light Source

    E-Print Network [OSTI]

    Thompson, Neil

    2011-01-01T23:59:59.000Z

    Electron Laser for the LBNL Next Generation Light SourceElectron Laser for the LBNL Next Generation Light SourceBerkeley National Laboratory (LBNL). The proposed facil- ity

  6. X-ray-optical cross-correlator for gas-phase experiments at the Linac Coherent Light Source free-electron laser

    SciTech Connect (OSTI)

    Schorb, S.; Cryan, J. P.; Glownia, J. M.; Bionta, M. R.; Coffee, R. N.; Swiggers, M.; Carron, S.; Castagna, J.-C.; Bozek, J. D.; Messerschmidt, M.; Schlotter, W. F.; Bostedt, C. [Linac Coherent Light Source, SLAC National Accelerator Laboratory, P.O. Box 20450, Stanford, California 94309 (United States); Gorkhover, T. [Institut fuer Optik und Atomare Physik, Technische Universitaet Berlin, Hardenbergstr. 36, 10623 Berlin (Germany); Erk, B.; Boll, R.; Schmidt, C.; Rudenko, A. [Max-Planck Advanced-Study-Group at CFEL, Notkestr. 85, 22607 Hamburg (Germany); Max-Planck-Institut f. Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); Rolles, D. [Max-Planck Advanced-Study-Group at CFEL, Notkestr. 85, 22607 Hamburg (Germany); Max-Planck-Institut f. med. Forschung, Jahnstr. 29, 69120 Heidelberg (Germany); Rouzee, A. [Max-Born-Institut, Max-Born-Str. 2, 12489 Berlin (Germany)

    2012-03-19T23:59:59.000Z

    X-ray-optical pump-probe experiments at the Linac Coherent Light Source (LCLS) have so far been limited to a time resolution of 280 fs fwhm due to timing jitter between the accelerator-based free-electron laser (FEL) and optical lasers. We have implemented a single-shot cross-correlator for femtosecond x-ray and infrared pulses. A reference experiment relying only on the pulse arrival time information from the cross-correlator shows a time resolution better than 50 fs fwhm (22 fs rms) and also yields a direct measurement of the maximal x-ray pulse length. The improved time resolution enables ultrafast pump-probe experiments with x-ray pulses from LCLS and other FEL sources.

  7. VOLUME 82, NUMBER 13 P H Y S I C A L R E V I E W L E T T E R S 29 MARCH 1999 Ginzburg-Landau Model and Single-Mode Operation of a Free-Electron Laser Oscillator

    E-Print Network [OSTI]

    Ng, Chung-Sang

    and Single-Mode Operation of a Free-Electron Laser Oscillator C. S. Ng and A. Bhattacharjee Department) It is shown that the radiation field in a long-pulse, low-gain free-electron laser oscillator obeys-9007(99)08757-8] PACS numbers: 41.60.Cr, 42.65.Tg, 52.35.Mw In a free-electron laser (FEL) oscillator, the intensity

  8. Design Features of a Planar Hybrid/Permanent Magnet Strong Focusing Undulator for Free Electron Laser (FEL) And Synchrotron Radiation (SR) Applications

    SciTech Connect (OSTI)

    Tatchyn, Roman; /SLAC

    2011-09-09T23:59:59.000Z

    Insertion devices for Angstrom-wavelength Free Electron Laser (FEL) amplifiers driven by multi-GeV electron beams generally require distributed focusing substantially stronger than their own natural focusing fields. Over the last several years a wide variety of focusing schemes and configurations have been proposed for undulators of this class, ranging from conventional current-driven quadrupoles external to the undulator magnets to permanent magnet (PM) lattices inserted into the insertion device gap. In this paper we present design studies of a flexible high-field hybrid/PM undulator with strong superimposed planar PM focusing proposed for a 1.5 Angstrom Linac Coherent Light Source (LCLS) driven by an electron beam with a 1 mm-mr normalized emittance. Attainable field parameters, tuning modes, and potential applications of the proposed structure are discussed.

  9. Recoil-Ion Momentum Distributions for Two-Photon Double Ionization of He and Ne by 44 eV Free-Electron Laser Radiation

    SciTech Connect (OSTI)

    Rudenko, A.; Moshammer, R.; Ullrich, J. [Max-Planck Advanced Study Group at CFEL, Notkestrasse 85, 22607 Hamburg (Germany); Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); Foucar, L.; Havermeier, T.; Smolarski, M.; Schoessler, S.; Cole, K.; Schoeffler, M.; Doerner, R. [Institut fuer Kernphysik, Universitaet Frankfurt, 60486 Frankfurt (Germany); Kurka, M.; Ergler, Th.; Kuehnel, K. U.; Jiang, Y. H.; Voitkiv, A.; Najjari, B.; Luedemann, S.; Schroeter, C. D. [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); Kheifets, A. [Research School of Physical Sciences, Australian University, Canberra, ACT 0200 (Australia); Duesterer, S. [DESY, Notkestrasse 85, 22607 Hamburg (Germany)] (and others)

    2008-08-15T23:59:59.000Z

    Recoil-ion momentum distributions for two-photon double ionization of He and Ne (({Dirac_h}/2{pi}){omega}=44 eV) have been recorded with a reaction microscope at FLASH (the free-electron laser at Hamburg) at an intensity of {approx}1x10{sup 14} W/cm{sup 2} exploring the dynamics of the two fundamental two-photon-two-electron reaction pathways, namely, sequential and direct (or nonsequential) absorption of the photons. We find strong differences in the recoil-ion momentum patterns for the two mechanisms pointing to the significantly different two-electron emission dynamics and thus provide serious constraints for theoretical models.

  10. Instability of wave modes in a two-stream free-electron laser with a helical wiggler and an axial magnetic field

    SciTech Connect (OSTI)

    Mohsenpour, Taghi; Mehrabi, Narges [Department of Physics, Faculty of Basic Sciences, University of Mazandaran, Babolsar (Iran, Islamic Republic of)] [Department of Physics, Faculty of Basic Sciences, University of Mazandaran, Babolsar (Iran, Islamic Republic of)

    2013-08-15T23:59:59.000Z

    The dispersion relation of a two-stream free-electron laser (TSFEL) with a one-dimensional helical wiggler and an axial magnetic field is studied. Also, all relativistic effects on the space-charge wave and radiation are considered. This dispersion relation is solved numerically to find the unstable interaction among the all wave modes. Numerical calculations show that the growth rate is considerably enhanced in comparison with single-stream FEL. The effect of the velocity difference of the two electron beams on the two-stream instability and the FEL resonance is investigated. The maximum growth rate of FEL resonance is investigated numerically as a function of the axial magnetic field.

  11. Design of a superconducting linear accelerator for an Infrared Free Electron Laser of the proposed Chemical Dynamics Research Laboratory at LBL

    SciTech Connect (OSTI)

    Chattopadhyay, S.; Byrns, R.; Donahue, R.; Edighoffer, J.; Gough, R.; Hoyer, E.; Kim, K.J.; Leemans, W.; Staples, J.; Taylor, B.; Xie, M.

    1992-08-01T23:59:59.000Z

    An accelerator complex has recently been designed at LBL as part of an Infrared Free Electron Laser facility in support of a proposed Chemical Dynamics Research Laboratory. We will outline the choice of parameters and design philosophy, which are strongly driven by the demand of reliable and spectrally stable operation of the FEL for very special scientific experiments. The design is based on a 500 MHz recirculating superconducting electron linac with highest energy reach of about 60 MeV. The accelerator is injected with beams prepared by a specially designed gun-buncher system and incorporates a near-isochronous and achromatic recirculation line tunable over a wide range of beam energies. The stability issues considered to arrive at the specific design will be outlined.

  12. Structural information extracted from the diffraction of XFEL fs-pulses in a crystal

    E-Print Network [OSTI]

    Leonov, A; Benediktovitch, A; Feranchuk, I; Pietsch, U

    2015-01-01T23:59:59.000Z

    We present a theoretical justification for a method of extracting of supplementary information for the phase retrieval procedure taken from diffraction of fs-pulses from X-ray Free Electron Laser facilities. The approach is based on numerical simulation of the dynamics of the electron density in the crystal composed of different atoms in the unit cell, namely a bi-atomic crystal containing heavy and light atoms. It is shown that evaluation of diffraction intensities measured by means of different values of XFEL pulse parameters enables to find absolute values of structure factors for both types of atoms and their relative phase. The accuracy of structural information is discussed in terms of fluctuations of the evaluated atomic scattering factors. Our approach could be important for improvement of phase retrieval methods with respect to a more efficient determination of atomic positions within the unit cell of macromolecules.

  13. Accelerator Design Study for a Soft X-Ray Free Electron Laser at the Lawrence Berkeley National Laboratory

    E-Print Network [OSTI]

    Kur, E.

    2010-01-01T23:59:59.000Z

    and Phase Diagnostics, SLAC Report LCLS-TN-00-12. Emma P.al. 2009, First Results of the LCLS Laser-Heater System, PACLinac Coherent Light Source (LCLS) Conceptual Design Report,

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

    E-Print Network [OSTI]

    Zhou, Zhongyuan; Chu, Shih-I

    2013-02-13T23:59:59.000Z

    been used to study multiphoton ionization processes of a hydrogen atom interacting with XUV laser fields [11,12]. It is shown that the photoelectron angular distributions (PADs) are quite different from those of the dipole approximation when the pulse... the dipole ones for laser pulses with a duration of five OCs [11]. This approach has also been used to investigate the multiphoton ionization processes of a hydrogen atom in excited states [13] and a hydrogen molecular ion H2+ [14]. The predicted PADs...

  15. IEEE JOURNAL OF QUANTUM ELECTRONICS, VOL. 27, NO. 12. DECEMBER 1991 2691 Applications of Infrared Free-Electron Lasers: Basic

    E-Print Network [OSTI]

    Fayer, Michael D.

    IEEE JOURNAL OF QUANTUM ELECTRONICS, VOL. 27, NO. 12. DECEMBER 1991 2691 Applications of Infrared. Fayer Invited Paper Abstract-Applications of tunable infrared (IR) picosecond (ps) pulses generated- heating are suggested. I. INTRODUCTION REE-ELECTRON lasers (FEL's) have developed Frapidly in the last 15

  16. DarkLight: A Search for Dark Forces at the Jefferson Laboratory Free-Electron Laser Facility

    E-Print Network [OSTI]

    J. Balewski; J. Bernauer; W. Bertozzi; J. Bessuille; B. Buck; R. Cowan; K. Dow; C. Epstein; P. Fisher; S. Gilad; E. Ihloff; Y. Kahn; A. Kelleher; J. Kelsey; R. Milner; C. Moran; L. Ou; R. Russell; B. Schmookler; J. Thaler; C. Tschalär; C. Vidal; A. Winnebeck; S. Benson; C. Gould; G. Biallas; J. R. Boyce; J. Coleman; D. Douglas; R. Ent; P. Evtushenko; H. C. Fenker; J. Gubeli; F. Hannon; J. Huang; K. Jordan; R. Legg; M. Marchlik; W. Moore; G. Neil; M. Shinn; C. Tennant; R. Walker; G. Williams; S. Zhang; M. Freytsis; R. Fiorito; P. O'Shea; R. Alarcon; R. Dipert; G. Ovanesyan; T. Gunter; N. Kalantarians; M. Kohl; I. Albayrak; M. Carmignotto; T. Horn; D. S. Gunarathne; C. J. Martoff; D. L. Olvitt; B. Surrow; X. Lia; R. Beck; R. Schmitz; D. Walther; K. Brinkmann; H. Zaunig

    2013-07-19T23:59:59.000Z

    We give a short overview of the DarkLight detector concept which is designed to search for a heavy photon A' with a mass in the range 10 MeV/c^2 free electon laser, and a way to extend DarkLight's reach using A' --> invisible decays.

  17. Mode-Locked Multichromatic X-Rays in a Seeded Free-Electron Laser for Single-Shot X-Ray Spectroscopy

    SciTech Connect (OSTI)

    Xiang, Dao; Ding, Yuantao; Raubenheimer, Tor; Wu, Juhao; /SLAC

    2012-05-10T23:59:59.000Z

    We present the promise of generating gigawatt mode-locked multichromatic x rays in a seeded free-electron laser (FEL). We show that, by using a laser to imprint periodic modulation in electron beam phase space, a single-frequency coherent seed can be amplified and further translated to a mode-locked multichromatic output in an FEL. With this configuration the FEL output consists of a train of mode-locked ultrashort pulses which span a wide frequency gap with a series of equally spaced sharp lines. These gigawatt multichromatic x rays may potentially allow one to explore the structure and dynamics of a large number of atomic states simultaneously. The feasibility of generating mode-locked x rays ranging from carbon K edge ({approx}284 eV) to copper L{sub 3} edge ({approx}931 eV) is confirmed with numerical simulation using the realistic parameters of the linac coherent light source (LCLS) and LCLS-II. We anticipate that the mode-locked multichromatic x rays in FELs may open up new opportunities in x-ray spectroscopy (i.e. resonant inelastic x-ray scattering, time-resolved scattering and spectroscopy, etc.).

  18. DarkLight: A Search for Dark Forces at the Jefferson Laboratory Free-Electron Laser Facility

    SciTech Connect (OSTI)

    Balewski, Jan; Bernauer, J.; Bertozzi, William; Bessuille, Jason; Buck, B.; Cowan, Ray; Dow, K.; Epstein, C.; Fisher, Peter; Gilad, Shalev; Ihloff, Ernest; Kahn, Yonatan; Kelleher, Aidan; Kelsey, J.; Milner, Richard; Moran, C.; Ou, Longwu; Russell, R.; Schmookler, Barak; Thaler, J.; Tschalar, C.; Vidal, Christopher; Winnebeck, A.; Benson, Stephen [JLAB; Gould, Christopher [JLAB; Biallas, George [JLAB; Boyce, James [JLAB; Coleman, James [JLAB; Douglas, David [JLAB; Ent, Rolf [JLAB; Evtushenko, Pavel [JLAB; Fenker, Howard [JLAB; Gubeli, Joseph [JLAB; Hannon, Fay [JLAB; Huang, Jia [JLAB; Jordan, Kevin [JLAB; Legg, Robert [JLAB; Marchlik, Matthew [JLAB; Moore, Steven [JLAB; Neil, George [JLAB; Shinn, Michelle D [JLAB; Tennant, Christopher [JLAB; Walker, Richard [JLAB; Williams, Gwyn [JLAB; Zhang, Shukui [JLAB; Freytsis, M.; Fiorito, Ralph; O'Shea, P.; Alarcon, Ricardo; Dipert, R.; Ovanesyan, G.; Gunter, Thoth; Kalantarians, Narbe; Kohl, M.; Albayrak, Ibrahim; Horn, Tanja; Gunarathne, D. S.; Martoff, C. J.; Olvitt, D. L.; Surrow, Bernd; Lia, X.; Beck, Reinhard; Schmitz, R.; Walther, D.; Brinkmann, K.; Zaunig, H.

    2014-05-01T23:59:59.000Z

    We give a short overview of the DarkLight detector concept which is designed to search for a heavy photon A' with a mass in the range 10 MeV/c^2 < m(A') < 90 MeV/c^2 and which decays to lepton pairs. We describe the intended operating environment, the Jefferson Laboratory free electon laser, and a way to extend DarkLight's reach using A' --> invisible decays.

  19. collaboration (Fig. 1). For all their promise, the LCLS and XFEL are large and expensive; the

    E-Print Network [OSTI]

    Cai, Long

    an existing particle accelera- tor, is about 300 million ($450 million), and XFEL will cost about 1 billion by combining the technology of lasers and electron accelerators (Fig. 2). A particle accelerator produces X-FEL. An even more advanced instrument under consideration6,7 is a high-gradient accel- erator

  20. Theoretical study of electronic damage in single particle imaging experiments at XFELs for pulse durations 0.1 - 10 fs

    E-Print Network [OSTI]

    Gorobtsov, O Yu; Kabachnik, N M; Vartanyants, I A

    2015-01-01T23:59:59.000Z

    X-ray free-electron lasers (XFELs) may allow to employ the single particle imaging (SPI) method to determine the structure of macromolecules that do not form stable crystals. Ultrashort pulses of 10 fs and less allow to outrun complete disintegration by Coulomb explosion and minimize radiation damage due to nuclear motion, but electronic damage is still present. The major contribution to the electronic damage comes from the plasma generated in the sample that is strongly dependent on the amount of Auger ionization. Since the Auger process has a characteristic time scale on the order of femtoseconds, one may expect that its contribution will be significantly reduced for attosecond pulses. Here, we study the effect of electronic damage on the SPI at pulse durations from 0.1 fs to 10 fs and in a large range of XFEL fluences to determine optimal conditions for imaging of biological samples. We analyzed the contribution of different electronic excitation processes and found that at fluences higher than $10^{13}$-$...

  1. Design and commissioning of vertical test cryostats for XFEL superconducting cavities measurements

    SciTech Connect (OSTI)

    Polinski, J.; Chorowski, M.; Duda, P. [Wroclaw University of Technology, Wyb. Wyspianskiego 27, 50-370 Wroclaw (Poland); Bozhko, Y.; Petersen, B.; Schaffran, J. [Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, D-22607Hamburg (Germany)

    2014-01-29T23:59:59.000Z

    The European X-ray Free Electron Laser (XFEL), now under construction at DESY in Hamburg, will make an extensive use of 1.3 GHz superconducting cavities aimed at accelerating the electrons to the energy of 17.5 GeV. The cavities will be operated at 2 K with the use of saturated HeII. Prior to their assembly in accelerator cryomodules, the RF performance of the cavities will be cold-tested in two dedicated vertical cryostats. Each cryostat allows a simultaneous testing of 4 cavities mounted on a dedicated insert. The cryostats are equipped with external lines allowing their supply with liquid helium and further conversion of the helium into superfluid He II. The paper describes the test stand flow scheme, the technical key elements, including a recuperative heat exchanger, and the cold commissioning. The thermodynamic analysis of the cryostat cool down and steady-state operation is given. A Second Law of Thermodynamics based theoretical model of the heat exchanger performance, and the model experimental validation, is presented.

  2. Towards simultaneous measurements of electronic and structural properties in ultra-fast x-ray free electron laser absorption spectroscopy experiments

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

    Gaudin, J.; Fourment, C.; Cho, B. I.; Engelhorn, K.; Galtier, E.; Harmand, M.; Leguay, P. M.; Lee, H. J.; Nagler, B.; Nakatsutsumi, M.; et al

    2014-04-17T23:59:59.000Z

    The rapidly growing ultrafast science with X-ray lasers unveils atomic scale processes with unprecedented time resolution bringing the so called “molecular movie” within reach. X-ray absorption spectroscopy is one of the most powerful x-ray techniques providing both local atomic order and electronic structure when coupled with ad-hoc theory. Collecting absorption spectra within few x-ray pulses is possible only in a dispersive setup. We demonstrate ultrafast time-resolved measurements of the LIII-edge x-ray absorption near-edge spectra of irreversibly laser excited Molybdenum using an average of only few x-ray pulses with a signal to noise ratio limited only by the saturation level ofmore »the detector. The simplicity of the experimental set-up makes this technique versatile and applicable for a wide range of pump-probe experiments, particularly in the case of non-reversible processes.« less

  3. 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)

    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

    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.

  4. Higher-order harmonic effect of a three-dimensional helical wiggler on the Larmor rotation of the equilibrium electrons in a free-electron laser with a positive or a reversed guide magnetic field

    SciTech Connect (OSTI)

    Zhang, Shi-Chang [Research Center for Advanced Computation, Xihua University, Chengdu SC610039, China and Institute of Photoelectronics, Southwest Jiaotong University, Chengdu SC610031 (China)] [Research Center for Advanced Computation, Xihua University, Chengdu SC610039, China and Institute of Photoelectronics, Southwest Jiaotong University, Chengdu SC610031 (China)

    2013-10-15T23:59:59.000Z

    Analytical formulas of the Larmor rotation are derived in detail for the equilibrium electrons motion in a free-electron laser with combination of a three-dimensional (3-D) helical wiggler and a positive or a reversed guide magnetic field. Generally, the Larmor radius in the configuration of a reversed guide field is much smaller than that in a positive guide field. At non-resonance, a helical orbit governed by the zero-order component of a 3-D wiggler field could hold; meanwhile, the higher-harmonic effect definitely influences those electrons with off-axis guiding centers and induces the electron-beam spreads. At resonance, the Larmor radius in the configuration of a positive guide field has a singularity with a limit tending to infinite, which causes all the electrons to hit the waveguide wall before the exit of the wiggler. Although Larmor-radius singularity does not exist in the configuration of a reversed guide field, at anti-resonance, the first-order harmonic of a 3-D wiggler field induces a transverse displacement which rapidly grows in proportion to a square of time, and leads part of the electron beam to hit the waveguide wall before reaching the wiggler exit, which depends on the specific parameters of the individual electrons. The analytical conclusions derived in the present paper are examined by the nonlinear simulations and the experimental observation. Disagreement with the previous literatures is discussed in detail.

  5. annular beam free-electron: Topics by E-print Network

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

    and X-ray regions is predicted. KeywordsFree-electron laser, Higher energy beam, Lower energy beam, Two-beam M. Zahedian; B. Maraghechi; M. H. Rouhani 6 Analytic model of...

  6. Metal Photocathodes for Free Electron Laser Applications

    E-Print Network [OSTI]

    Greaves, Corin Michael Ricardo

    2012-01-01T23:59:59.000Z

    any problems to prola@aps.org PRB, p. 4334. url: http://any problems to prola@aps.org PRB, p. 3641. url: http://any problems to prola@aps.org PRB, p. 3464. url: http://

  7. Hole Coupling Resonator for Free Electron Lasers

    E-Print Network [OSTI]

    Xie, M.

    2011-01-01T23:59:59.000Z

    3. Total round-trip power loss, coupling efficiency and themicron. Total round-trip power loss and coupling efficiencythe total fractional power loss per round trip, the hole

  8. Axial interaction free-electron laser

    DOE Patents [OSTI]

    Carlsten, Bruce E. (Los Alamos, NM)

    1997-01-01T23:59:59.000Z

    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.

  9. Axial interaction free-electron laser

    DOE Patents [OSTI]

    Carlsten, B.E.

    1997-09-02T23:59:59.000Z

    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.

  10. Free-Electron Laser | Jefferson Lab

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItem NotEnergy,ARMFormsGasReleaseSpeechesHall ATours, Research Inspecting an injector

  11. 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...

  12. Quasi-free electron energy in near critical point helium

    E-Print Network [OSTI]

    Findley, Gary L.

    Quasi-free electron energy in near critical point helium Yevgeniy Lushtak a,b , Samantha B, Monroe, LA 71209 Abstract We present for the first time the quasi-free electron energy V0() in helium from low density to the density of the triple point liquid (gaseous helium/liquid helium I

  13. Short Wavelength Seeding through Compression for Fee Electron Lasers

    E-Print Network [OSTI]

    Qiang, Ji

    2010-01-01T23:59:59.000Z

    tunable short wavelength free electron lasers (FELs) providereduces the laser power needed for the generation of shortbetween the laser ?eld and the electron beam inside a short

  14. STELLA-II Experiment Update on Monoenergetic Laser Acceleration

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

    during Staged Electron Laser Acceleration (STELLA) Experiment* - Used inverse free electron laser (IFEL) as laser acceleration mechanism - IFEL buncher (IFEL1) creates...

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

    SciTech Connect (OSTI)

    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

    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%.

  16. UNDULATOR-BASED LASER WAKEFIELD ACCELERATOR ELECTRON BEAM DIAGNOSTIC

    E-Print Network [OSTI]

    Bakeman, M.S.

    2010-01-01T23:59:59.000Z

    ultra-short, high-peak- current, electron beams are ideal for driving a compact XUV free electron laser (

  17. A Plasma Channel Beam Conditioner for a Free Electron Laser

    E-Print Network [OSTI]

    Penn, G.; Sessler, A.M.; Wurtele, J.S.

    2008-01-01T23:59:59.000Z

    Nature 445, 6741 (2007). [7] LCLS Design Study Group, SLACLinac Coherent Light Source (LCLS) [7]. One example has thefunction in the FEL. For LCLS parameters, the corresponding

  18. HIGH AVERAGE POWER UV FREE ELECTRON LASER EXPERIMENTS AT JLAB

    SciTech Connect (OSTI)

    Douglas, David; Evtushenko, Pavel; Gubeli, Joseph; Hernandez-Garcia, Carlos; Legg, Robert; Neil, George; Powers, Thomas; Shinn, Michelle D; Tennant, Christopher

    2012-07-01T23:59:59.000Z

    Having produced 14 kW of average power at {approx}2 microns, JLAB has shifted its focus to the ultraviolet portion of the spectrum. This presentation will describe the JLab UV Demo FEL, present specifics of its driver ERL, and discuss the latest experimental results from FEL experiments and machine operations.

  19. Spreader Design for FERMI@Elettra Free Electron Laser

    E-Print Network [OSTI]

    2008-01-01T23:59:59.000Z

    Berkeley, CA 94720, USA 2) Sincrotrone Trieste , 34012Basovizza, Trieste, Italy Abstract In this note we describe

  20. Development of free-electron lasers for xuv projection lithography

    SciTech Connect (OSTI)

    Newnam, B.E.

    1990-01-01T23:59:59.000Z

    Future rf-linac-driven FELs, operating in the range from 4 nm to 100 nm, could be excellent exposure tools for extending the resolution limit of projection optical lithography to {le}0.1 {mu}m and with adequate total depth of focus (1 to 2 {mu}m). When operated at a moderate duty rate of {ge}1%, XUV FELs should be able to supply sufficient average power to support high-volume chip production. Recent developments of the electron beam, magnetic undulator, and resonator mirrors are described which raise our expectation that FEL operation below 100 nm is almost ready for demonstration. Included as a supplement is a review of initial design studies of the reflecting XUV projection optics, fabrication of reflection masks, characterization of photoresists, and the first experimental demonstrations of the capability of projection lithography with 14-nm radiation to produce lines and spaces as small as 0.05 {mu}m. 88 refs., 10 figs.

  1. Free electron in a laser field: The nonrelativistic solution

    E-Print Network [OSTI]

    C. Yuce

    2006-12-11T23:59:59.000Z

    Schrodinger equation for a charged particle interacting with the plane wave electromagnetic field is solved exactly. The exact analytic solution and the perturbative solution up to second order are compared.

  2. Gamma-ray free-electron lasers: Quantum fluid model

    E-Print Network [OSTI]

    Silva, H M

    2014-01-01T23:59:59.000Z

    A quantum fluid model is used to describe the interacion of a nondegenerate cold relativistic electron beam with an intense optical wiggler taking into account the beam space-charge potential and photon recoil effect. A nonlinear set of coupled equations are obtained and solved numerically. The numerical results shows that in the limit of plasma wave-breaking an ultra-high power radiation pulse are emitted at the$\\gamma$-ray wavelength range which can reach an output intensity near the Schwinger limit depending of the values of the FEL parameters such as detuning and input signal initial phase at the entrance of the interaction region.

  3. Simulation of free-electron lasers seeded with broadband radiation

    E-Print Network [OSTI]

    Bajlekov, Svetoslav

    2012-01-01T23:59:59.000Z

    in Proceedings of FEL 2006 (BESSY, Berlin, Germany, 2006) p.in Proceedings of FEL 2006 (BESSY, Berlin, Germany, 2006) p.in Proceedings of FEL 2006 (BESSY, Berlin, Germany, 2006) p.

  4. fel 2005 :: Free Electron Laser Conference and Workshop

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron4 Self-Scrubbing:,, , ., ...,exerciseTheoretical Investigationsfor Texas

  5. XFEL diffraction: developing processing methods to optimize data quality

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

    Sauter, Nicholas K.

    2015-03-01T23:59:59.000Z

    Serial crystallography, using either femtosecond X-ray pulses from free-electron laser sources or short synchrotron-radiation exposures, has the potential to reveal metalloprotein structural details while minimizing damage processes. However, deriving a self-consistent set of Bragg intensities from numerous still-crystal exposures remains a difficult problem, with optimal protocols likely to be quite different from those well established for rotation photography. Here several data processing issues unique to serial crystallography are examined. It is found that the limiting resolution differs for each shot, an effect that is likely to be due to both the sample heterogeneity and pulse-to-pulse variation in experimental conditions. Shotsmore »with lower resolution limits produce lower-quality models for predicting Bragg spot positions during the integration step. Also, still shots by their nature record only partial measurements of the Bragg intensity. An approximate model that corrects to the full-spot equivalent (with the simplifying assumption that the X-rays are monochromatic) brings the distribution of intensities closer to that expected from an ideal crystal, and improves the sharpness of anomalous difference Fourier peaks indicating metal positions.« less

  6. Laser-PlasmaWakefield Acceleration with Higher Order Laser Modes

    E-Print Network [OSTI]

    Geddes, C.G.R.

    2011-01-01T23:59:59.000Z

    Design considerations for a laser-plasma linear collider,"E.Esarey, and W.P.Leemans, "Free-electron laser driven bythe LBNL laser-plasma accelerator," in Proc. Adv. Acc. Con.

  7. aluminium laser ablation: Topics by E-print Network

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

    radiation, FLASH (Free-electron LASer in Hamburg) provides ultra-intense femtosecond radiation and laser optics: UV, XUV, and X-ray lasers; (140.2600) Lasers and laser optics:...

  8. Energy of the quasi-free electron in xenon Xianbo Shi a

    E-Print Network [OSTI]

    Findley, Gary L.

    Energy of the quasi-free electron in xenon Xianbo Shi a , Luxi Li a , C.M. Evans a,, G.L. Findley b critical point. The energy of the quasi-free electron, arising from dopant field ionization, in xenon and for the critical isotherm. Key words: supercritical xenon, field ionization, quasi-free electron energy, electron

  9. The energy of the quasi-free electron in near critical point nitrogen

    E-Print Network [OSTI]

    Findley, Gary L.

    The energy of the quasi-free electron in near critical point nitrogen Yevgeniy Lushtak a,b , C the density dependent quasi-free electron energy V0() in the strongly absorbing gas N2 for the first time. V0-Seitz model, repulsive fluids, quasi-free electron energy, critical point effects PACS: 79.60.-i, 34.80.-i, 82

  10. Radiation Shielding for Electronic Devices OperatingRadiation Shielding for Electronic Devices Operating in XFEL Environment: Monte Carlo Simulations andin XFEL Environment: Monte Carlo Simulations and

    E-Print Network [OSTI]

    Radiation Shielding for Electronic Devices OperatingRadiation Shielding for Electronic Devices undergroundund tunnel. All LLRF Electronic Devices, made of radiation sensitivetunnel. All LLRF Electronic principle of the dedicated radiationtion shielding for the electronic devices to be operating in XFEL

  11. New Laser's "First Light" Shatters Record | Jefferson...

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

    Jefferson National Accelerator Facility have delivered first light from their Free Electron Laser (FEL). Only 2 years after ground was broken for the FEL, infrared light of more...

  12. Numerical estimation on free electrons generated by shielded radioactive materials under various gaseous environments

    SciTech Connect (OSTI)

    Kim, D. S. [Department of Physics, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798 (Korea, Republic of); Lee, W. S.; So, J. H. [Agency for Defence Development (ADD), Daejeon 305-152 (Korea, Republic of); Choi, E. M. [Department of Physics, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798 (Korea, Republic of); School of Electrical and Computer Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798 (Korea, Republic of)

    2013-06-15T23:59:59.000Z

    We report simulation results on generation of free electrons due to the presence of radioactive materials under controlled pressure and gases using a general Monte Carlo transport code (MCNPX). A radioactive material decays to lower atomic number, simultaneously producing high energy gamma rays that can generate free electrons via various scattering mechanisms. This paper shows detailed simulation works for answering how many free electrons can be generated under the existence of shielded radioactive materials as a function of pressure and types of gases.

  13. Energy of the Quasi-free Electron in Argon and Krypton C. M. Evans1,

    E-Print Network [OSTI]

    Findley, Gary L.

    Energy of the Quasi-free Electron in Argon and Krypton C. M. Evans1, and G. L. Findley2, 1 these data, a new local Wigner- Seitz model for the density dependent energy V0(P) of a quasi-free electron/medium polarization energy, and includes the thermal kinetic energy of the quasi-free electron. Using this model, V0(P

  14. Ultrafast imaging of complex systems in 3-D at near atomic resolution...

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

    on ultrafast timescales using extremely intense X-ray free-electron laser (XFEL) pulses. One important step toward ultrafast imaging of samples with a single X-ray shot is...

  15. Nanofabrication of Diffractive X-ray Optics for Synchrotrons...

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

    the soft x-ray range and down to 15 nm in the multi keV range. For use at x-ray free-electron laser (XFEL) sources, diffractive optics must be capable of withstanding extreme...

  16. Lensless X-Ray Imaging in Reflection

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

    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...

  17. Compact X-ray Free Electron Laser from a Laser-plasma Accelerator using a

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power Administration would like submit the followingth Lomonosov1

  18. Energy of the Quasi-free Electron in Supercritical Krypton near the Critical Point Luxi Li and C. M. Evans

    E-Print Network [OSTI]

    Evans, Cherice M.

    Energy of the Quasi-free Electron in Supercritical Krypton near the Critical Point Luxi Li and C. M by the quasi-free electron that arises from field ionization of the dopant, and the zero point kinetic energy of the free electron. The overall decrease in the shift of the dopant ionization energy near the critical

  19. Energy of the quasi-free electron in supercritical argon near the critical point C.M. Evans1,

    E-Print Network [OSTI]

    Evans, Cherice M.

    Energy of the quasi-free electron in supercritical argon near the critical point C.M. Evans1 to the interaction between argon and the quasi-free electron arising from field ionization of the dopant. The energy by the ionic core, V0(P) is the quasi-free electron energy in the perturbing medium, and P is the perturber

  20. fLasHThe Free-Electron Laser new technologies for new science: Soon X-ray free-electron lasers

    E-Print Network [OSTI]

    , how molecular machines really work. Accelerators | photon Science | particle physics Deutsches in the accel- erator tunnel. The photon beam transport system in the hall delivers the FEL pulses ­ as short the feasibility of a superconducting linear electron-positron collider for elementary particle phy- sics

  1. Undulator-Based Laser Wakefield Accelerator Electron Beam Energy Spread and Emittance Diagnostic

    E-Print Network [OSTI]

    Bakeman, M.S.

    2011-01-01T23:59:59.000Z

    ultra-short, high- peak-current, electron beams are ideal for driving a compact X U V free electron laser (

  2. Manufacturing Considerations of the Magnetic Structures for the Undulators for the X-FEL at TESLA

    E-Print Network [OSTI]

    1 Manufacturing Considerations of the Magnetic Structures for the Undulators for the X-FEL at TESLA DESY / HASYLAB Notkestr. 85, 22607 Hamburg, Germany TESLA-FEL 2000-10 Abstract A study is presented FELs. The total magnetic length of the magnet structures is 1405m. It is proposed to produce these huge

  3. X-FEL Report 2004-04 DSP Integrated, Parameterized, FPGA Based

    E-Print Network [OSTI]

    X-FEL Report 2004-04 DSP Integrated, Parameterized, FPGA Based Cavity Simulator & Controller for UV-FEL and X-Ray FEL). The controller bases on a programmable circuit Xilinx VirtexII V3000 embedded on a PCB, VHDL, FEL, TESLA, TTF, UV-FEL, Xilinx, FPGA based systems, LLRF control system of third generation

  4. Tunable Laser Reaches Record Power Level | Jefferson Lab

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

    (Jefferson Lab) have produced record setting levels of laser power from their Free Electron Laser (FEL). Last summer when the FEL was first turned on, it produced 155 watts of...

  5. Modeling of free electronic state density in hydrogenic plasmas based on nearest neighbor approximation

    SciTech Connect (OSTI)

    Nishikawa, Takeshi, E-mail: nishikawa.takeshi@okayama-u.ac.jp [Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530 (Japan)

    2014-07-15T23:59:59.000Z

    Most conventional atomic models in a plasma do not treat the effect of the plasma on the free-electron state density. Using a nearest neighbor approximation, the state densities in hydrogenic plasmas for both bound and free electrons were evaluated and the effect of the plasma on the atomic model (especially for the state density of the free electron) was studied. The model evaluates the electron-state densities using the potential distribution formed by the superposition of the Coulomb potentials of two ions. The potential from one ion perturbs the electronic state density on the other. Using this new model, one can evaluate the free-state density without making any ad-hoc assumptions. The resulting contours of the average ionization degree, given as a function of the plasma temperature and density, are shifted slightly to lower temperatures because of the effect of the increasing free-state density.

  6. Drive laser Photocathode

    E-Print Network [OSTI]

    Anlage, Steven

    Drive laser Gun cavity Scale 2" 3"0 1" Photocathode Schematic Overview of a Free Electron Laser Steel Sleeve Compressed Cs2CrO4:Ti Pellet (0.725g) 1.27 cm Nickel-Assisted Hermetic Braze #12;Foundation

  7. Performance study of a soft X-ray harmonic generation FEL seeded with an EUV laser pulse

    E-Print Network [OSTI]

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

    2007-01-01T23:59:59.000Z

    X-ray Harmonic Generation FEL Seeded with an EUV Laser PulseX-ray harmonic generation FEL seeded with an EUV laser pulseof a free electron laser (FEL) using a low-power extreme

  8. TESLA-FEL 2004-03 Proposed continuous wave energy recovery operation of an XFEL*

    E-Print Network [OSTI]

    of the LCLS and 20 GeV in the case of the DESY XFEL. For both, the charge per bunch is 1 nC and the transverse normalized emittance is ~1.4 µm·rad. The rms bunch length is 80 fs (DESY) and 97 fs (LCLS). The difference in the average brilliance mostly results from the number of bunches per second, which is 120 in the LCLS design

  9. Energy of the quasi-free electron in argon, krypton and xenon Xianbo Shi a,b

    E-Print Network [OSTI]

    Findley, Gary L.

    Energy of the quasi-free electron in argon, krypton and xenon Xianbo Shi a,b , Luxi Li a,b , C. M ionization of the dopant, and (iii) the kinetic energy of the quasi-free electron. The polarization terms are determined by a standard statistical mechanical treatment. However, the kinetic energy of the quasi-free

  10. Experimental Demonstration of a Soft X-ray Self-seeded Free-electron Laser

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

    Ratner, D. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Abela, R. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Amann, J. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Behrens, C. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Bohler, D. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Bouchard, G. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Bostedt, C. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Boyes, M. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Chow, K. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Cocco, D. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Decker, F. J. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Ding, Y. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Eckman, C. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Emma, P. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Fairley, D. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Feng, Y. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Field, C. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Flechsig, U. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Gassner, G. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Hastings, J. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Heimann, P. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Huang, Z. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Kelez, N. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Krzywinski, J. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Loos, H. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Lutman, A. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Marinelli, A. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Marcus, G. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Maxwell, T. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Moeller, S. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Morton, D. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Nuhn, H. D. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Rodes, N. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Schlotter, W. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Serkez, S. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Stevens, T. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Turner, J. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Walz, D. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Welch, J. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Wu, J. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States)

    2015-02-06T23:59:59.000Z

    The Linac Coherent Light Source (LCLS) has added self-seeding capability to the soft x-ray range using a grating monochromator system. We report demonstration of soft x-ray self-seeding with a measured resolving power of 2000-5000, wavelength stability of 10-4, and an increase in peak brightness by a factor of 2-5 across the photon energy range of 500-1000 eV. By avoiding the need for a monochromator at the experimental station, the self-seeded beam can deliver as much as 50 fold higher brightness to users.

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

    E-Print Network [OSTI]

    Staples, John

    2009-01-01T23:59:59.000Z

    wavelength seed, and ultrafast pulses. Understanding gainedlasers to produce ultrafast x-ray pulses at the ALS in a “is home to the PULSE Institute for ultrafast energy science,

  12. Exact and variational solutions of 3D Eigenmodes in high gain Free Electron Lasers

    E-Print Network [OSTI]

    Xie, M.

    2011-01-01T23:59:59.000Z

    Phys. Rev. A 41, 1662 [11] LCLS Design Study Report, SLAC-R-radial mode index. Consider LCLS nominal case as an exampleai/a r )2] (Ar/1f(Jx). For the LCLS example, the variational

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

    E-Print Network [OSTI]

    Staples, John

    2009-01-01T23:59:59.000Z

    2007). 41. P. Emma for the LCLS commissioning team, PAC2009Test Facility for the LCLS”, SLAC-TN-07-005, (2007). John N.Professional/Academic Director, LCLS Strategic Projects

  14. Three-dimensional analysis of free-electron laser performance using brightness scaled variables

    E-Print Network [OSTI]

    Gullans, M.

    2008-01-01T23:59:59.000Z

    to the Linac Coherent Light Source (LCLS) design, ESASEon the LCLS, and the optimal gain for a ?xed emittance.The parameters for LCLS used here are a beam energy of 13.64

  15. Design Studies for a VUV--Soft X-ray Free-Electron Laser Array

    E-Print Network [OSTI]

    Corlett, J.

    2010-01-01T23:59:59.000Z

    bunch arrival time in the LCLS, and another system that willFERMI@Elettra and 100 fs for LCLS, both requiring about 200-

  16. Femtosecond diffractive imaging with a soft-X-ray free-electron laser (CXIDB ID 3)

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

    Chapman, H. N.

    The diffraction pattern of this entry corresponds to the one shown in **figure 2a** of the corresponding citation.

  17. Design Overview of a Highly Stable Infrared Free Electron Laser at LBL

    E-Print Network [OSTI]

    Kim, K.-J.

    2011-01-01T23:59:59.000Z

    except for a slight linear droop. Such a system is inthere will remain significant droop over the macropulse (due

  18. Influence of finite radial geometry on the growth rate of ion-channel free electron laser

    SciTech Connect (OSTI)

    Bahmani, Mohammad; Hamzehpour, Hossein [Department of Physics, K.N. Toosi University of Technology, Tehran 15875-4416 (Iran, Islamic Republic of)] [Department of Physics, K.N. Toosi University of Technology, Tehran 15875-4416 (Iran, Islamic Republic of); Hasanbeigi, Ali [Department of Physics and Institute for Plasma Research, Kharazmi University, 49 Dr. Mofateh Avenue, Tehran 15614 (Iran, Islamic Republic of)] [Department of Physics and Institute for Plasma Research, Kharazmi University, 49 Dr. Mofateh Avenue, Tehran 15614 (Iran, Islamic Republic of)

    2013-11-15T23:59:59.000Z

    The influence of finite radial geometry on the instability of a tenuous relativistic electron beam propagating in an ion-channel in a waveguide is investigated. The instability analysis is based on the linearized Vlasov-Maxwell equations for the perturbation about a self-consistent beam equilibrium. With the help of characteristic method the dispersion relation for the TE-mode is derived and analyzed through the numerical solutions. It is found that the positioning of the beam radius R{sub b} relative to the waveguide radius R{sub c}, and the ion-channel frequency can have a large influence on the maximum growth rate and corresponding wave number.

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

    E-Print Network [OSTI]

    Staples, John

    2009-01-01T23:59:59.000Z

    Advanced Light Source Accelerator Physics Group - LBNLlasers. Studied accelerator physics issues associated withInstructor: o Fund. of Accelerator Physics and Technology,

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

    Office of Science (SC) Website

    ultrahigh brightness in the 10 eV vacuum ultraviolet region via harmonic production. The FEL is based on the superconducting radiofrequency (SRF) technology developed...

  1. Analytical formula of Free Electron Laser exponential gain for non-resonant electron beam

    E-Print Network [OSTI]

    Jia, Qika

    2014-01-01T23:59:59.000Z

    The FEL gain formulas for non-resonant case are studied. For the mono-energetic and non-resonant electron beam, the exact expression of the solution of the FEL characteristic cubic equation is obtained with a form much more simple than that in the literatures, and the gain length as the function of the detuning parameter is explicitly given, then the gain for different detuning parameter and from low to high can be easily calculated. A simplified approximation formula is also given for the exponential gain calculation in the non-resonant case. For the case of the electron beam with an energy spread, the solution of the characteristic cubic equation is given explicitly for rectangular energy distribution and Lorentz distribution, respectively. Moreover the explicit expression also can be used for the solution of the characteristic cubic equation including the impact of the space charge. The transition from the low gain to the high gain is analyzed. The variations of the gain bandwidth and of the detuning param...

  2. Analysis and optimization of a free-electron laser with an irregular waveguide

    E-Print Network [OSTI]

    V. A. Goryashko

    2010-04-08T23:59:59.000Z

    Using a time-dependent approach the analysis and optimization of a planar FEL-amplifier with an axial magnetic field and an irregular waveguide is performed. By applying methods of nonlinear dynamics three-dimensional equations of motion and the excitation equation are partly integrated in an analytical way. As a result, a self-consistent reduced model of the FEL is built in special phase space. The reduced model is the generalization of the Colson-Bonifacio model and takes into account the intricate dynamics of electrons in the pump magnetic field and the intramode scattering in the irregular waveguide. The reduced model and concepts of evolutionary computation are used to find optimal waveguide profiles. The numerical simulation of the original non-simplified model is performed to check the effectiveness of found optimal profiles. The FEL parameters are chosen to be close to the parameters of the experiment (S. Cheng et al. IEEE Trans. Plasma Sci. 1996, vol. 24, p. 750), in which a sheet electron beam with the moderate thickness interacts with the TE01 mode of a rectangular waveguide. The results strongly indicate that one can improve the efficiency by a factor of five or six if the FEL operates in the magnetoresonance regime and if the irregular waveguide with the optimized profile is used.

  3. Frequency response of an atomic resonance driven by weak free-electron-laser fluctuating pulses

    E-Print Network [OSTI]

    G M Nikolopoulos; P Lambropoulos

    2014-01-20T23:59:59.000Z

    Motivated by recent experiments pertaining to the interaction of weak SASE-FEL pulses with atoms and molecules, we investigate the conditions under which such interactions can be described in the framework of a simple phase-diffusion model with decorrelated atom-field dynamics. The nature of the fluctuations that are inevitably present in SASE-FEL pulses is shown to play a pivotal role in the success of the decorrelation. Our analysis is performed in connection with specific recent experimental results from FLASH in the soft X-ray regime.

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

    SciTech Connect (OSTI)

    Barends, Thomas, R.M.

    2013-11-25T23:59:59.000Z

    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.

  5. Cyclotron-undulator cooling of a free-electron-laser beam

    SciTech Connect (OSTI)

    Bandurkin, I. V.; Kuzikov, S. V. [Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod (Russian Federation); Savilov, A. V. [Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod (Russian Federation); Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod (Russian Federation)

    2014-08-18T23:59:59.000Z

    We propose methods of fast cooling of an electron beam, which are based on wiggling of particles in an undulator in the presence of an axial magnetic field. We use a strong dependence of the axial electron velocity on the oscillatory velocity, when the electron cyclotron frequency is close to the frequency of electron wiggling in the undulator field. The abnormal character of this dependence (when the oscillatory velocity increases with the increase of the input axial velocity) can be a basis of various methods for fast cooling of moderately relativistic (several MeV) electron beams.

  6. Three-dimensional theory of Smith-Purcell free-electron laser with dielectric loaded grating

    SciTech Connect (OSTI)

    Cao, Miaomiao, E-mail: mona486@yeah.net; Li, Ke, E-mail: like3714@163.com [Key Laboratory of High Power Microwave Sources and Technologies, Institute of Electronics, Chinese Academy of Sciences, Beijing 100190 (China); University of Chinese Academy of Sciences, School of Electronic Science and Technology, Beijing 100049 (China); Liu, Wenxin, E-mail: lwenxin@mail.ie.ac.cn; Wang, Yong, E-mail: wangyong3845@sina.com [Key Laboratory of High Power Microwave Sources and Technologies, Institute of Electronics, Chinese Academy of Sciences, Beijing 100190 (China)

    2014-09-14T23:59:59.000Z

    A dielectric loaded rectangular grating for Smith-Purcell devices is proposed in this paper. Regarding the electron beam as a moving plasma dielectric, a three dimensional (3D) linear theory of beam-wave interaction is developed. The first and second order growth rates are calculated, which are obtained by expanding hot dispersion equation at synchronous point. The results show that the cutoff frequency is affected by grating width. The dispersion curve becomes flatter and shifts towards lower frequency by loading dielectric in grooves. The simulation results, which are obtained by a 3D particle-in-cell code, are in good agreement with theoretical calculations. Compared the first and second order growth rate, it shows that the discrepancy is large when beam parameters are selected with high values. In this case, it is necessary to apply the second order growth rate, which can accurately describe the process of beam-wave interaction.

  7. Harmonics suppression effect of the quasi-periodic undulator in SASE free-electron-laser

    E-Print Network [OSTI]

    Ai-Lin Wu; Qi-Ka Jia; He-Ting Li

    2013-05-03T23:59:59.000Z

    In this paper, the harmonics suppression effect of QPUs in SASE FEL is investigated. The numerical results show that the harmonics power is reduced by using QPUs, but the fundamental radiation power also has a pronounced decrease as the saturation length gets very long. The cases of employing QPUs as parts of undulators are studied. The calculations show that if the fraction of QPUs and their offgap are appropriate in an undulator system, the harmonics radiation could be suppressed remarkably, meanwhile the fundamental saturation length does not increase too much.

  8. On the possible void decay in free-electron laser sase-fel experiment

    E-Print Network [OSTI]

    J Marciak-Kozlowska; M Pelc; M Kozlowski

    2007-05-21T23:59:59.000Z

    In this paper the motion of ultrahigh energy particles produced in sasefel is investigated. The critical field which opose the acceleration of the ultra high energy particles is calculated

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

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

    Barends, Thomas, R.M.

    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.

  10. First operation of a Free-Electron Laser generating GW power radiation at 32 nm wavelength

    E-Print Network [OSTI]

    , 97074 Würzburg, Germany 3 BESSY GmbH, Albert-Einstein-Str.15, 12489 Berlin, Germany 4 Center Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22603 Hamburg, Germany 7 Deutsches Elektronen-Synchrotron

  11. Novel adiabatic bifilar helical wiggler entrance for free-electron laser applications

    SciTech Connect (OSTI)

    Hartemann, F.; Buzzi, J.M.; Lamain, H.

    1988-08-22T23:59:59.000Z

    A new adabatic bifilar helical wiggler entrance is presented. This introduction region is obtained by using a liquid shunt resistance to progressively shunt the current circulating in the wiggler helical windings. We have built a prototype wiggler and measured the field profiles obtained with this new scheme. The results agree very well with computer calculations and show that, indeed, one obtains a high quality adiabatic wiggler with this method.

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

    E-Print Network [OSTI]

    Staples, John

    2009-01-01T23:59:59.000Z

    CW superconducting RF (SCRF) linac technology, and opticalCollider and the DOE-funded SCRF R&D program. SLAC can apply

  13. Femtosecond dark-field imaging with an X-ray free electron laser (CXIDB ID 19)

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

    Martin, A. V.

    This data was collected as part of the same experiment as the data deposited in [ID16](id-16.html). Experiment details are given in [Loh, N.D. et al.](http://dx.doi.org/10.1038/nature11222)

  14. Autocorrelation measurements of free-electron laser radiation using a two-photon QWIP

    E-Print Network [OSTI]

    Perera, A. G. Unil

    ]. Besides thermography, the high electrical bandwidth of QWIPs provides interesting opportunities in new

  15. VISA: A Milestone on the Path Towards X-Ray Free Electron Lasers...

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

    duration of 100 to 1000 times shorter. We can, however, be confident that the X-ray SASE-FEL, by opening to our exploration a totally new range of physical parameters, will lead to...

  16. Free electron laser with bunched relativistic electron beam and electrostatic longitudinal wiggler

    SciTech Connect (OSTI)

    Sepehri Javan, Nasser [Department of Physics, University of Mohaghegh Ardabili, P.O. Box 179, Ardabil (Iran, Islamic Republic of)

    2010-06-15T23:59:59.000Z

    The system of the nonlinear nonstationary equations describing spatial-temporal dynamics of the amplitudes of an undulator radiation and a space charge wave of a relativistic electron beam in the resonator is obtained. The electrostatic longitudinal wiggler is considered. A bunch of the electron beam injects to the resonator, at the ends of which two mirrors are placed. After the interaction of electrons of bunch with radiation in the presence of wiggler and after amplifying electromagnetic pulse, a part of radiation is reflected back by semitransparent mirror. Then, it reaches to the initial of the system where the other mirror is placed. Synchronously, when the pulse is reflecting, the other electron bunch enters to the resonator and interacts with the pulse. This operation has simulated until saturation of growth of the electromagnetic pulse. The dynamics of the problem is simulated by the method of macro particles. The dynamics of pulse amplification, motion of the electrons, and spectra of output radiation in each stage are simulated.

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

    E-Print Network [OSTI]

    Loss, Daniel

    Synchrotron Radiation Laboratory, Stanford Linear Accelerator Center, 2575 Sand Hill Road, Menlo Park the sample explodes and turns into a plasma. Here we report the first experimental demonstration-resolution scattering signals for such samples in conventional experiments11,12 . Damage is caused by energy deposited

  18. THE SYSTEM OF POWER SUPPLIES, CONTROL AND MODULATION OF ELECTRON GUN FOR FREE ELECTRON LASER

    E-Print Network [OSTI]

    Kozak, Victor R.

    inverter, timer and two fiber optic converters. Power inverter has 220V input line with 50 or 60Hz. The output of power inverter is connected to input coil of isolated power transformer (300kV). Timer Optic converter St 1GHz ACStabilazer Power Inverter 20kHz CAN Fiber Optic Converter 1MHz St Fiber Optic

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

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC) EnvironmentalGyroSolé(tm)HydrogenRFP » ImportantOffice ofOffice of Scientific and

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

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisitingContract Management Fermi SitePART IScientific andOfficeScientific andOffice

  1. Navy Breaks World Record With Futuristic Free-Electron Laser (FOX News.com)

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible for Renewable Energy:Nanowire Solar541,9337, 2011 at 2:00 P.M.Innovation Portal|

  2. Jefferson Lab's Free-Electron Laser Joins With Others in New Research

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12electron beam charges upJeffersonFridayMarch 6 |31Venture |

  3. Jefferson Lab's free-electron laser joins new research venture (Optics.org)

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12electron beam charges upJeffersonFridayMarch 6| Jefferson

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

    Office of Environmental Management (EM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33Frequently AskedEnergyIssuesEnergy SolarRadioactive LiquidSavings for Specific U.S.TheTheFirst

  5. VISA: A Milestone on the Path Towards X-Ray Free Electron Lasers | Stanford

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengthening aTurbulenceUtilize Available Resources Print As soonof

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

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist. CategoryFebruaryFebruary 17,Time-Delay X-ray Holography

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

    Office of Science (SC) Website

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurTheBrookhaven NationalRegionalsResearch » ClimateFebruaryFermiFlorida(SC)

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

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist.Newof EnergyFundingGeneGenomeGeoffreyGeorge A. LowLab

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

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengthening a solidSynthesis of 2Dand Water |1Benefits ofEffects

  10. High-power, high-intensity laser propagation and interactions

    SciTech Connect (OSTI)

    Sprangle, Phillip [Plasma Physics Division, Naval Research Laboratory, Washington, DC 20375 (United States); Electrical and Computer Engineering and Physics, University of Maryland, College Park, Maryland 20740 (United States); Hafizi, Bahman [Plasma Physics Division, Naval Research Laboratory, Washington, DC 20375 (United States)

    2014-05-15T23:59:59.000Z

    This paper presents overviews of a number of processes and applications associated with high-power, high-intensity lasers, and their interactions. These processes and applications include: free electron lasers, backward Raman amplification, atmospheric propagation of laser pulses, laser driven acceleration, atmospheric lasing, and remote detection of radioactivity. The interrelated physical mechanisms in the various processes are discussed.

  11. Design Parameters and Commissioning of Vertical Inserts Used for Testing the XFEL Superconducting Cavities

    E-Print Network [OSTI]

    J. Schaffran; Y. Bozhko; B. Petersen; D. Meissner; M. Chorowski; J. Polinski

    2013-06-26T23:59:59.000Z

    The European XFEL is a new research facility currently under construction at DESY in the Hamburg area in Germany. From 2015 on, it will generate extremely intense X-ray flashes that will be used by researchers from all over the world. The superconducting XFEL linear accelerator consists of 100 accelerator modules with more than 800 RF-cavities inside. The accelerator modules, superconducting magnets and cavities will be tested in the accelerator module test facility (AMTF). This paper gives an overview of the design parameters and the commissioning of the vertical insert, used in two cryostats (XATC) of the AMTF-hall. The Insert serves as a holder for 4 nine-cell cavities. This gives the possibility to cool down 4 cavities to 2K in parallel and, consequently, to reduce the testing time. The following RF measurement, selected as quality check, will be done separately for each cavity. Afterwards the cavities will be warmed up again and will be sent to the accelerator module assembly.

  12. Fully QED/relativistic theory of light pressure on free electrons by isotropic radiation

    E-Print Network [OSTI]

    A. E. Kaplan

    2015-02-25T23:59:59.000Z

    A relativistic/QED theory of light pressure on electrons by an isotropic, in particular blackbody radiation predicts thermalization rates of free electrons over entire span of energies available in the lab and the nature. The calculations based on the QED Klein-Nishina theory of electron-photon scattering and relativistic Fokker-Planck equation, show that the transition from classical (Thompson) to QED (Compton) thermalization determined by the product of electron energy and radiation temperature, is reachable under conditions for controlled nuclear fusion, and predicts large acceleration of electron thermalization in the Compton domain.

  13. Fully QED/relativistic theory of light pressure on free electrons by isotropic radiation

    E-Print Network [OSTI]

    A. E. Kaplan

    2015-05-19T23:59:59.000Z

    A relativistic/QED theory of light pressure on electrons by an isotropic, in particular blackbody radiation predicts thermalization rates of free electrons over entire span of energies available in the lab and the nature. The calculations based on the QED Klein-Nishina theory of electron-photon scattering and relativistic Fokker-Planck equation, show that the transition from classical (Thompson) to QED (Compton) thermalization determined by the product of electron energy and radiation temperature, is reachable under conditions for controlled nuclear fusion, and predicts large acceleration of electron thermalization in the Compton domain and strong damping of plasma oscillations at the temperatures near plasma nuclear fusion.

  14. Peculiarities of the Light Absorption and Emission by Free Electrons in Multivalley Semiconductors

    E-Print Network [OSTI]

    P. M. Tomchuk

    2008-11-18T23:59:59.000Z

    General expressions are obtained for the coefficient of light absorption by free carriers as well as the intensity of the spontaneous light emission by hot electrons in multivalley semiconductors. These expressions depend on the electron concentration and electron temperature in the individual valleys. An anisotropy of the dispersion law and electron scattering mechanisms is taken into account. Impurity-related and acoustic scattering mechanisms are analyzed. Polarization dependence of the spontaneous emission by hot electrons is found out. At unidirectional pressure applied or high irradiation intensities, the polarization dependence also appears in the coefficient of light absorption by free electrons.

  15. Space Charge Compensation in Laser Particle Accelerators L.C...

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

    shown in Fig. 1, is composed of an energy modulator (e.g. an inverse free-electron laser) followed by a drift section. A macrobunch with little energy spread enters the...

  16. Propagation of gamma rays and production of free electrons in air

    SciTech Connect (OSTI)

    Dimant, Y. S. [Center for Space Physics, Boston University, Boston, Massachusetts 02215 (United States); Nusinovich, G. S.; Romero-Talamas, C. A.; Granatstein, V. L. [Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, Maryland 20742-3511 (United States); Sprangle, P.; Penano, J. [Plasma Physics Division, Naval Research Laboratory, Washington, DC 20375-5320 (United States)

    2012-10-15T23:59:59.000Z

    This paper is devoted to the analysis of production of free electrons in air by gamma-rays leaking from radioactive materials. A model based on the Klein-Nishina scattering theory is used to calculate scattering cross sections and approximate the electron production rate. The model includes the effects of primary gamma-quanta radiated by the source as well as that scattered in air. Comparison of the model with the mcnpx kinetic code (http://mcnpx.lanl.gov/) in a sample problem shows excellent agreement. The motivation for this research comes from the recently proposed concept of remote detection of concealed radioactive materials [V. L. Granatstein and G. S. Nusinovich, J. Appl. Phys. 108, 063304 (2010)]. The concept is based on the breakdown in air at the focal point of a high-power beam of electromagnetic waves produced by a THz gyrotron with a 10-20 {mu}s pulse. The presence of a radioactive material can greatly exceed the production rate of free electrons over the natural background rate. Additional electrons act as seeds to initiate the breakdown and create sufficiently dense plasma at the focal region. The dense plasma can then be remotely detected as an unambiguous effect of the concealed radioactive material.

  17. Amplified short-wavelength light scattered by relativistic electrons in the laser-induced optical lattice

    E-Print Network [OSTI]

    Andriyash, I A; Malka, V; d'Humières, E; Balcou, Ph

    2014-01-01T23:59:59.000Z

    The scheme of the XUV/X-ray free electron laser based on the optical undulator created by two overlapped transverse laser beams is analyzed. A kinetic theoretical description and an ad hoc numerical model are developed to account for the finite energy spread, angular divergence and the spectral properties of the electron beam in the optical lattice. The theoretical findings are compared to the results of the one- and three-dimensional numerical modeling with the spectral free electron laser code PLARES.

  18. Fiber optic probe of free electron evanescent fields in the optical frequency range

    SciTech Connect (OSTI)

    So, Jin-Kyu, E-mail: js1m10@orc.soton.ac.uk; MacDonald, Kevin F. [Optoelectronics Research Centre and Centre for Photonic Metamaterials, University of Southampton, Highfield, Southampton SO17 1BJ (United Kingdom); Zheludev, Nikolay I. [Optoelectronics Research Centre and Centre for Photonic Metamaterials, University of Southampton, Highfield, Southampton SO17 1BJ (United Kingdom); Centre for Disruptive Photonic Technologies, Nanyang Technological University, Singapore 637371 (Singapore)

    2014-05-19T23:59:59.000Z

    We introduce an optical fiber platform which can be used to interrogate proximity interactions between free-electron evanescent fields and photonic nanostructures at optical frequencies in a manner similar to that in which optical evanescent fields are sampled using nanoscale aperture probes in scanning near-field microscopy. Conically profiled optical fiber tips functionalized with nano-gratings are employed to couple electron evanescent fields to light via the Smith-Purcell effect. We demonstrate the interrogation of medium energy (30–50?keV) electron fields with a lateral resolution of a few micrometers via the generation and detection of visible/UV radiation in the 700–300?nm (free-space) wavelength range.

  19. Statistical properties of the radiation from SASE FEL operating in a post-saturation regime with and without undulator tapering

    E-Print Network [OSTI]

    Schneidmiller, E A

    2015-01-01T23:59:59.000Z

    We describe statistical and coherence properties of the radiation from x-ray free electron lasers (XFEL) operating in the post-saturation regime. We consider practical case of the SASE3 FEL at the European XFEL. We perform comparison of the main characteristics of the X-ray FEL operating in the post-saturation regime with and without undulator tapering: efficiency, coherence time and degree of transverse coherence.

  20. Technical Report Ultrafast X-ray Science at the Sub-Picosecond Pulse Source

    E-Print Network [OSTI]

    Wechsler, Risa H.

    1 Technical Report Ultrafast X-ray Science at the Sub-Picosecond Pulse Source Kelly J. Gaffney ultrafast phenomena. These techniques involve excitation of a sample with an ultrafast laser pump pulse, USA The ultrafast, high brightness x-ray free electron laser (XFEL) sources of the future have

  1. Proceedings of the 2007 Aging Aircraft Conference Cost Model for Assessing the Transition to Lead-Free Electronics

    E-Print Network [OSTI]

    Sandborn, Peter

    Proceedings of the 2007 Aging Aircraft Conference Cost Model for Assessing the Transition to Lead the cost ramifications of the transition from tin- lead to lead-free electronic parts. All tin-lead, all lead-free and mixed assembly approaches are considered. The model makes basic assumptions of a fixed

  2. Laser satellite power systems

    SciTech Connect (OSTI)

    Walbridge, E.W.

    1980-01-01T23:59:59.000Z

    A laser satellite power system (SPS) converts solar power captured by earth-orbiting satellites into electrical power on the earth's surface, the satellite-to-ground transmission of power being effected by laser beam. The laser SPS may be an alternative to the microwave SPS. Microwaves easily penetrate clouds while laser radiation does not. Although there is this major disadvantage to a laser SPS, that system has four important advantages over the microwave alternative: (1) land requirements are much less, (2) radiation levels are low outside the laser ground stations, (3) laser beam sidelobes are not expected to interfere with electromagnetic systems, and (4) the laser system lends itself to small-scale demonstration. After describing lasers and how they work, the report discusses the five lasers that are candidates for application in a laser SPS: electric discharge lasers, direct and indirect solar pumped lasers, free electron lasers, and closed-cycle chemical lasers. The Lockheed laser SPS is examined in some detail. To determine whether a laser SPS will be worthy of future deployment, its capabilities need to be better understood and its attractiveness relative to other electric power options better assessed. First priority should be given to potential program stoppers, e.g., beam attenuation by clouds. If investigation shows these potential program stoppers to be resolvable, further research should investigate lasers that are particularly promising for SPS application.

  3. Researchers' Hottest New Laser Beams 14.2 kW | Jefferson Lab

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

    press release The linear accelerator portion of the FEL. On Thursday, Oct. 26, Free-Electron Laser (FEL) team members knew they were within reach of a goal they'd pursued for two...

  4. Towards laser based improved experimental schemes for multiphoton e+ e- pair production from vacuum

    E-Print Network [OSTI]

    I. Ploumistakis; S. D. Moustaizis; I. Tsohantjis

    2009-07-15T23:59:59.000Z

    Numerical estimates for pair production from vacuum in the presence of strong electromagnetic fields are derived, for two experimental schemes : the First concerns a laser based X-FEL and the other imitates the E144 experiment. The approximation adopted in this work is that of two level multiphoton on resonance. Utilizing achievable values of laser beam parameters, an enhancedproduction efficiency of up to 10^11 and 10^15 pairs can be obtained, for the two schemes respectively.

  5. Structure of CPV17 polyhedrin determined by the improved analysis of serial femtosecond crystallographic data

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

    Ginn, Helen M.; Messerschmidt, Marc; Ji, Xiaoyun; Zhang, Hanwen; Axford, Danny; Gildea, Richard J.; Winter, Graeme; Brewster, Aaron S.; Hattne, Johan; Wagner, Armin; et al

    2015-03-09T23:59:59.000Z

    The X-ray free-electron laser (XFEL) allows the analysis of small weakly diffracting protein crystals, but has required very many crystals to obtain good data. Here we use an XFEL to determine the room temperature atomic structure for the smallest cytoplasmic polyhedrosis virus polyhedra yet characterized, which we failed to solve at a synchrotron. These protein microcrystals, roughly a micron across, accrue within infected cells. We use a new physical model for XFEL diffraction, which better estimates the experimental signal, delivering a high-resolution XFEL structure (1.75 Å), using fewer crystals than previously required for this resolution. The crystal lattice and proteinmore »core are conserved compared with a ?polyhedrin with less than 10% sequence identity. We explain how the conserved biological phenotype, the crystal lattice, is maintained in the face of extreme environmental challenge and massive evolutionary divergence. Our improved methods should open up more challenging biological samples to XFEL analysis.« less

  6. Nb-Pb superconducting RF-gun TESLA-FEL Report 2005-09

    E-Print Network [OSTI]

    continuous wave (cw) or near-cw operation of far future x-ray free electron laser facilities (XFELs) driven Jefferson National Accelerator Facility, 12000 Jefferson Ave., Newport News, VA 23606, USA J. Langner, P to operate at high duty factors also and provide good quality electron beams. An example of such an injector

  7. TESLA Report 2005-19 WARSAW UNIVERSITY OF TECHNOLOGY

    E-Print Network [OSTI]

    research center in co- operation with European partners will produce high-intensity ultra-short X will produce high-intensity ultra-short X-ray fl Appendixes 67 II #12;CONTENTS Abstract The X-ray free-electron laser XFEL that is being planned at the DESY

  8. Longitudinally Coherent Single-Spike Radiation from a Self-Amplified Spontaneous Emission Free-Electron Laser

    E-Print Network [OSTI]

    Marcus, Gabriel Andrew

    2012-01-01T23:59:59.000Z

    tleties in modern ultrafast pulse measurement techniques.amplitude and phase of ultrafast pulses from the phase-spacephase-space picture of ultrafast pulses is developed with a

  9. Multicolor operation and spectral control in a gain-modulated x-ray free-electron laser

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    Coherent Light Source (LCLS, at SLAC) [1], SACLA (RIKEN) [experimental demonstration at LCLS. FIG. 1 (color online).demonstrated experimentally at LCLS. The experimental beam

  10. Longitudinally Coherent Single-Spike Radiation from a Self-Amplified Spontaneous Emission Free-Electron Laser

    E-Print Network [OSTI]

    Marcus, Gabriel Andrew

    2012-01-01T23:59:59.000Z

    light at saturation for the LCLS FEL case with a 4.5 GeV e-light at saturation for the LCLS FEL case with a 4.5 GeV e-along the undulator for the LCLS FEL case with a 4.5 GeV e-

  11. 1.1 Simulations of a Free-Electron Laser Oscillator at Jefferson Lab Lasing in the Vacuum Ultraviolet

    SciTech Connect (OSTI)

    Shinn, Michelle D. [JLAB; Benson, Stephen V. [JLAB

    2013-04-01T23:59:59.000Z

    The UVFEL at Jefferson Lab has provided a 10 eV photon beam for users by outcoupling the coherent third harmonic of the UVFEL operated at 372 nm. This can provide up to tens of milliwatts of power in the VUV. Operation of the FEL at the fundamental might enhance this power by up to a factor of 1000. With minor upgrades to the accelerator now underway and a new undulator proposed by Calabazas Creek Research, Inc. we show that we can lase in the fundamental at 124 nm. The predicted output is higher by four orders of magnitude on an average power basis and six orders of magnitude on a peak fluence basis than the Advanced Light Source at Lawrence Berkeley National Laboratory.

  12. Modern problems in Statistical Physics of Bose-Einstein Condensation and in Electrodynamics of Free Electron Lasers 

    E-Print Network [OSTI]

    Dorfman, Konstantin E.

    2010-07-14T23:59:59.000Z

    description of a dilute Bose gas was formulated by Bogoliubov [5-8, 22, 23]. The main idea is in separating the condensate contribution to the bosonic field operator. In general, the field operator can be written as ??(r) =summationtextk?k(r)?ak, where ?k... of the systematic application of the quantum field theory to an interacting sys- tem of bosons due to Beliaev [7, 8, 22]. This leads to a generalized Green?s function formalism, which builds in the crucial role of the Bose condensate and allows one to determine...

  13. Accelerator Design Study for a Soft X-Ray Free Electron Laser at the Lawrence Berkeley National Laboratory

    E-Print Network [OSTI]

    Kur, E.

    2010-01-01T23:59:59.000Z

    074401. Kramer D. et al. , 2004, The BESSY Soft X-ray FreeTechnical Design Report, BESSY, Berlin http://www.bessy.de.Project [Moncton et al. ], BESSY FEL [Kramer et al. ], LBNL

  14. First Observation of Self-Amplified Spontaneous Emission in a Free-Electron Laser at 109 nm Wavelength

    E-Print Network [OSTI]

    Boyer, Edmond

    , 9700 S. Cass Avenue, Argonne, IL 60439, USA, 2 BESSY, Albert-Einstein-Strasse 15, 12489 Berlin, Germany, 64289 Darmstadt, Germany 6 Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22603 Hamburg, Germany 7 Deutsches Elektronen-Synchrotron DESY, Platanenallee 6, 15738 Zeuthen, Germany 8 Faculty

  15. Multicolor operation and spectral control in a gain-modulated x-ray free-electron laser

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    PRL 111, 134801 (2013) PHYSICAL REVIEW LETTERS week ending2013 PHYSICAL REVIEW LETTERS PRL 111, 134801 (2013) where uPHYSICAL REVIEW LETTERS PRL 111, 134801 (2013) i u expði u

  16. Modern problems in Statistical Physics of Bose-Einstein Condensation and in Electrodynamics of Free Electron Lasers

    E-Print Network [OSTI]

    Dorfman, Konstantin E.

    2010-07-14T23:59:59.000Z

    description of a dilute Bose gas was formulated by Bogoliubov [5-8, 22, 23]. The main idea is in separating the condensate contribution to the bosonic field operator. In general, the field operator can be written as ??(r) =summationtextk?k(r)?ak, where ?k... of the systematic application of the quantum field theory to an interacting sys- tem of bosons due to Beliaev [7, 8, 22]. This leads to a generalized Green?s function formalism, which builds in the crucial role of the Bose condensate and allows one to determine...

  17. Laser Phase Errors in Seeded FELs

    SciTech Connect (OSTI)

    Ratner, D.; Fry, A.; Stupakov, G.; White, W.; /SLAC

    2012-03-28T23:59:59.000Z

    Harmonic seeding of free electron lasers has attracted significant attention from the promise of transform-limited pulses in the soft X-ray region. Harmonic multiplication schemes extend seeding to shorter wavelengths, but also amplify the spectral phase errors of the initial seed laser, and may degrade the pulse quality. In this paper we consider the effect of seed laser phase errors in high gain harmonic generation and echo-enabled harmonic generation. We use simulations to confirm analytical results for the case of linearly chirped seed lasers, and extend the results for arbitrary seed laser envelope and phase.

  18. Charge Conjugation, Heavy Ions, e^+ e^- pairs: Was there a better way to add potentials to Dirac's free electrons?

    E-Print Network [OSTI]

    Samuel P. Bowen; Jay D. Mancini

    2012-03-26T23:59:59.000Z

    This is a study of a possible alternative procedure for adding a potential energy to the free electron Dirac equation. When Dirac added potentials to his free electron equation, there were two alternatives (here called D1 and D2). He chose D1 and lost charge conjugation symmetry, found Ehrenfest equations that depended on the sign of the energy of the state determining the expectation value, encountered Klein tunneling, zitterbewegung and the Klein paradox. The D1 alternative also predicted that deep potentials should pull positive energy states down into the negative energy continuum, possibly creating an unstable vacuum. Extensive experiments (1975-1997) found no evidence for this instability, but did find low energy electron-positron pairs with sharply defined energies and unusually low counting statistics. These pairs tended to disappear with higher beam currents. This paper explores the other alternative, here called D2 and finds charge conjugation symmetry preserved, Ehrenfest equations are classical, Klein tunneling is not present, unstable vacuua are forbidden, zitterbewegung is absent in the charge current density, new excitations of bound electron-positron pairs are possible in atoms, and the energies at which low energy electron-positron pair production in heavy ion scattering occurs is well described. Also all of the positive energy calculations, including those with the Coulomb potential, the hydrogen-like atom, are retained exactly the same as found in alternative D1. It might have been better if Dirac had chosen alternative D2.

  19. Photonic laser-driven accelerator for GALAXIE

    SciTech Connect (OSTI)

    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

    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.

  20. Stern-Gerlach surfing in laser wakefield accelerators

    E-Print Network [OSTI]

    Flood, Stephen P

    2015-01-01T23:59:59.000Z

    We investigate the effects of a Stern-Gerlach-type addition to the Lorentz force on electrons in a laser wakefield accelerator. The Stern-Gerlach-type terms are found to generate a family of trajectories describing electrons that surf along the plasma density wave driven by a laser pulse. Such trajectories could lead to an increase in the size of an electron bunch, which may have implications for attempts to exploit such bunches in future free electron lasers.

  1. SEEDED VISA: A 1064nm LASER-SEEDED FEL AMPLIFIER AT THE M. Dunning, G. Andonian, E. Hemsing, S. Reiche, J. Rosenzweig

    E-Print Network [OSTI]

    Brookhaven National Laboratory

    SEEDED VISA: A 1064nm LASER-SEEDED FEL AMPLIFIER AT THE BNL ATF M. Dunning, G. Andonian, E. Hemsing Free Electron Laser (FEL) using the VISA undulator and a Nd:YAG seed laser will be performed for a short Rayleigh length FEL amplifier at 1 micron to allow for high power transmission with min- imal

  2. Coherent diffraction of a single virus particle: The impact of a water layer on the available orientational information

    SciTech Connect (OSTI)

    Wang, F.; Weckert, E.; Ziaja, B.; Larsson, D. S. D.; Spoel, D. van der [HASYLAB, Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22607 Hamburg (Germany); Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22607 Hamburg (Germany); Department of Cell and Molecular Biology, Uppsala University, Box 596, S-75124 Uppsala (Sweden)

    2011-03-15T23:59:59.000Z

    Coherent diffractive imaging using x-ray free-electron lasers (XFELs) may provide a unique opportunity for high-resolution structural analysis of single particles sprayed from an aqueous solution into the laser beam. As a result, diffraction images are measured from randomly oriented objects covered by a water layer. We analyze theoretically how the thickness of the covering water layer influences the structural and orientational information contained in the recorded diffraction images. This study has implications for planned experiments on single-particle imaging with XFELs.

  3. Laser Assisted Emittance Exchange

    SciTech Connect (OSTI)

    Xiang, Dao; /SLAC

    2012-06-11T23:59:59.000Z

    We describe here the laser assisted emittance exchange (LAEE) technique. A laser operating in the transverse mode (TEM10 or TEM01) is used to interact with the electron beam in a dispersive region and to initiate the transverse-to-longitudinal emittance exchange. It is shown that with the LAEE one can generate an electron beam with ultralow transverse emittance, which allows one to significantly bring down the size of an X-ray free electron laser (FEL) and greatly extend the availability of these light sources. The technique can also be used to enhance the performances of X-ray FELs in storage rings. The timing and energy jitter problems for the standard emittance exchange and LAEE techniques are also discussed.

  4. Fiber optic probe of free electron evanescent fields in the optical frequency range Jin-Kyu So, Kevin F. MacDonald, and Nikolay I. Zheludev

    E-Print Network [OSTI]

    Zheludev, Nikolay

    Fiber optic probe of free electron evanescent fields in the optical frequency range Jin-Kyu So fabrication of bent near-field optical fiber probes by electric arc heating Rev. Sci. Instrum. 69, 3843 (1998 of thermal evaporation conditions used in coating aluminum on near-field fiber-optic probes Rev. Sci. Instrum

  5. Light Well: ATunable Free-Electron Light Source on a Chip K. F. MacDonald,1,* Y. H. Fu,2

    E-Print Network [OSTI]

    Zheludev, Nikolay

    Light Well: ATunable Free-Electron Light Source on a Chip G. Adamo,1 K. F. MacDonald,1,* Y. H. Fu,2 metal-dielectric structure creates a new type of tunable, nanoscale radiation source--a ``light well''. In the reported demonstration, tunable light is generated at an intensity of $200 W=cm2 as electrons with energies

  6. Direct Laser Synthesis of Functional Coatings

    SciTech Connect (OSTI)

    P. Schaaf; Michelle D. Shinn; E. Carpene; J. Kaspar

    2005-06-01T23:59:59.000Z

    The direct laser synthesis of functional coatings employs the irradiation of materials with short intensive laser pulses in a reactive atmosphere. The material is heated and plasma is ignited in the reactive atmosphere. This leads to an intensive interaction of the material with the reactive species and a coating is directly formed on the materials surface. By that functional coatings can be easily produced a fast way on steel, aluminium, and silicon by irradiation in nitrogen, methane, or even hydrogen. The influence of the processing parameters to the properties of the functional coatings will be presented for titanium nitride coating produced on titanium with the free electron laser.

  7. Laser Plasma Material Interactions

    SciTech Connect (OSTI)

    Schaaf, Peter; Carpene, Ettore [Universitaet Goettingen, II. Physikalisches Institut, Friedrich-Hund-Platz 1, 37077 Goettingen (Germany)

    2004-12-01T23:59:59.000Z

    Surface treatment by means of pulsed laser beams in reactive atmospheres is an attractive technique to enhance the surface features, such as corrosion and wear resistance or the hardness. Many carbides and nitrides play an important role for technological applications, requiring the mentioned property improvements. Here we present a new promising fast, flexible and clean technique for a direct laser synthesis of carbide and nitride surface films by short pulsed laser irradiation in reactive atmospheres (e.g. methane, nitrogen). The corresponding material is treated by short intense laser pulses involving plasma formation just above the irradiated surface. Gas-Plasma-Surface reactions lead to a fast incorporation of the gas species into the material and subsequently the desired coating formation if the treatment parameters are chosen properly. A number of laser types have been used for that (Excimer Laser, Nd:YAG, Ti:sapphire, Free Electron Laser) and a number of different nitride and carbide films have been successfully produced. The mechanisms and some examples will be presented for Fe treated in nitrogen and Si irradiated in methane.

  8. Efficient electronic structure calculation for molecular ionization dynamics at high x-ray intensity

    E-Print Network [OSTI]

    Hao, Yajiang; Hanasaki, Kota; Son, Sang-Kil; Santra, Robin

    2015-01-01T23:59:59.000Z

    We present the implementation of an electronic-structure approach dedicated to ionization dynamics of molecules interacting with x-ray free-electron laser (XFEL) pulses. In our scheme, molecular orbitals for molecular core-hole states are represented by linear combination of numerical atomic orbitals that are solutions of corresponding atomic core-hole states. We demonstrate that our scheme efficiently calculates all possible multiple-hole configurations of molecules formed during XFEL pulses. The present method is suitable to investigate x-ray multiphoton multiple ionization dynamics and accompanying nuclear dynamics, providing essential information on the chemical dynamics relevant for high-intensity x-ray imaging.

  9. Optical laser systems at the Linac Coherent Light Source

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

    Minitti, Michael P.; Robinson, Joseph S.; Coffee, Ryan N.; Edstrom, Steve; Gilevich, Sasha; Glownia, James M.; Granados, Eduardo; Hering, Philippe; Hoffmann, Matthias C.; Miahnahri, Alan; et al

    2015-05-01T23:59:59.000Z

    Ultrafast optical lasers play an essential role in exploiting the unique capabilities of recently commissioned X-ray free-electron laser facilities such as the Linac Coherent Light Source (LCLS). Pump–probe experimental techniques reveal ultrafast dynamics in atomic and molecular processes and reveal new insights in chemistry, biology, material science and high-energy-density physics. This manuscript describes the laser systems and experimental methods that enable cutting-edge optical laser/X-ray pump–probe experiments to be performed at LCLS.

  10. XFEL 2004 - Program

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsingWhat isJoin theanniversaryI 1 0

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

    SciTech Connect (OSTI)

    Son, S. [18 Caleb Lane, Princeton, New Jersey 08540 (United States); Joon Moon, Sung [8 Benjamin Rush Ln., Princeton, New Jersey 08540 (United States)

    2012-06-15T23:59:59.000Z

    A dense electron beam propagating through a laser undulator can radiate a coherent x-ray or gamma ray. This lasing scheme is studied with the Landau damping theory. The analysis suggests that, with currently available physical parameters, coherent gamma rays of up to 50 keV can be generated. The electron quantum diffraction suppresses the free electron laser action, which limits the maximum radiation.

  12. Inner-Shell Multiple Ionization of Polyatomic Molecules With an Intense X-Ray Free-Electron Laser Studied By Coincident Ion Momentum Imaging

    SciTech Connect (OSTI)

    Erk, B. [Max Planck Advanced Study Group and Deutsches Elektronen-Synchrotron, Hamburg (Germany); Max Planck Inst. for Nuclear Physics, Heidelberg (Germany); Rolles, D. [Max Planck Advanced Study Group and Deutsches Elektronen-Synchrotron, Hamburg (Germany); Max Planck Inst. for Medical Rearch, Heidelburg (Germany); Foucar, L. [Max Planck Society, Hamburg (Germany); Max Planck Inst. for Medical Rearch, Heidelburg (Germany); Rudek, B. [Max Planck Advanced Study Group and Deutsches Elektronen-Synchrotron, Hamburg (Germany); Max Planck Inst. for Nuclear Physics, Heidelberg (Germany); Epp, S. W. [Max Planck Society, Hamburg (Germany). Max Planck Inst. for Nuclear Physics; Max Planck Inst. for Nuclear Physics, Heidelberg (Germany); Cryle, M. [Max Planck Inst. for Medical Rearch, Heidelburg (Germany); Bostedt, C. [SLAC National Accelerator Lab., Menlo Park, CA (United States). Linac Coherent Light Source; Schorb, S. [SLAC National Accelerator Lab., Menlo Park, CA (United States). Linac Coherent Light Source; Technical Univ. Berlin (Germany). Inst. for Optic and Atomic Physics; Bozek, J. [SLAC National Accelerator Lab., Menlo Park, CA (United States). Linac Coherent Light Source; Rouzee, A. [Max Born Inst., Berlin (Germany); Hundertmark, A. [Max Born Inst., Berlin (Germany); Marchenko, T. [Laboratory of Chemical Physics, Paris (France); Simon, M. [Laboratory of Chemical Physics, Paris (France); Filsinger, F. [Fritz Haber Inst. for Max Planck Gesellschaft, Berlin (Germany); Christensen, L. [Aarhus Univ. (Denmark). Dept. of Physics and Astronomy; De, S. [Aarhus Univ. (Denmark). Dept. of Chemistry; Saha Inst. of Nuclear Physics, Kolkata (India); Trippel, S. [Center for Free-Electron Laser Science (CFEL), Hamburg (Germany); Küpper, J. [Center for Free-Electron Laser Science (CFEL) and Univ. of Hamburg, Hamburg (Germany). Dept. of Physics, Center for Ultrafast Imaging; Stapelfeldt, H. [Aarhus Univ. (Denmark). Dept. of Chemistry; Wada, S. [SLAC National Accelerator Lab., Menlo Park, CA (United States). Linac Coherent Light Source; Hiroshima Univ., Higashi-Hiroshima (Japan), Dept. of Physical Science; Ueda, K. [Tohoku Univ., Sendai (Japan). IMRAM; Swiggers, M. [SLAC National Accelerator Lab., Menlo Park, CA (United States). Linac Coherent Light Source; Messerschmidt, M. [SLAC National Accelerator Lab., Menlo Park, CA (United States). Linac Coherent Light Source; Schröter, C. D. [Max Planck Inst. for Nuclear Physics, Heidelberg (Germany); Moshammer, R. [Max Planck Society, Hamburg (Germany). Max Planck Inst. for Nuclear Physics; Max Planck Inst. for Nuclear Physics, Heidelberg (Germany); Schlichting, I. [Max Planck Society, Hamburg (Germany); Max Planck Inst. for Medical Rearch, Heidelburg (Germany); Ullrich, J. [Max Planck Society, Hamburg (Germany). Max Planck Inst. for Nuclear Physics; Max Planck Inst. for Nuclear Physics, Heidelberg (Germany); National Institute for Physics and Technology, Braunschweig (Germany); Rudenko, A. [Max Planck Society, Hamburg (Germany). Max Planck Inst. for Nuclear Physics; Max Planck Inst. for Nuclear Physics, Heidelberg (Germany); Kansas State Univ., Manhattan, KS (United States). Dept. of Physics

    2013-08-28T23:59:59.000Z

    The ionization and fragmentation of two selenium containing hydrocarbon molecules, methylselenol (CH3SeH) and ethylselenol (C2H5SeH), by intense (>1017 W cm-2 ) 5 fs x-ray pulses with photon energies of 1.7 and 2 keV has been studied by means of coincident ion momentum spectroscopy. Measuring charge states and ion kinetic energies, we find signatures of charge redistribution within the molecular environment. Furthermore, by analyzing fragment ion angular correlations, we can determine the laboratory-frame orientation of individual molecules and thus investigate the fragmentation dynamics in the molecular frame. This allows distinguishing protons originating from different molecular sites along with identifying the reaction channels that lead to their emission.

  13. The FERMI@Elettra free-electron-laser source for coherent X-ray physics: photon properties, beam transport system, and applications

    E-Print Network [OSTI]

    Allaria, Enrico

    2010-01-01T23:59:59.000Z

    colleagues at Sincrotrone Trieste and elsewhere working onF-TN-07/12 (Sincrotrone Trieste) [11] Boscolo I and Stagno VF Parmigiani 1,3 Sincrotrone Trieste S.C.p.A. , Trieste (

  14. Differential cross sections for non-sequential double ionization of He by 52 eV photons from the Free Electron Laser in Hamburg, FLASH

    E-Print Network [OSTI]

    Kling, Matthias

    Feist3,4 , D A Horner5 , A Rudenko1,2 , Y H Jiang1 , K U Kühnel1 , L Foucar1,2 , T N Rescigno6 , C W Mc

  15. Inner-Shell Multiple Ionization of Polyatomic Molecules With an Intense X-Ray Free-Electron Laser Studied By Coincident Ion Momentum Imaging

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

    Erk, B.; Rolles, D.; Foucar, L.; Rudek, B.; Epp, S. W.; Cryle, M.; Bostedt, C.; Schorb, S.; Bozek, J.; Rouzee, A.; et al

    2013-08-28T23:59:59.000Z

    The ionization and fragmentation of two selenium containing hydrocarbon molecules, methylselenol (CH3SeH) and ethylselenol (C2H5SeH), by intense (>1017 W cm-2 ) 5 fs x-ray pulses with photon energies of 1.7 and 2 keV has been studied by means of coincident ion momentum spectroscopy. Measuring charge states and ion kinetic energies, we find signatures of charge redistribution within the molecular environment. Furthermore, by analyzing fragment ion angular correlations, we can determine the laboratory-frame orientation of individual molecules and thus investigate the fragmentation dynamics in the molecular frame. This allows distinguishing protons originating from different molecular sites along with identifying the reactionmore »channels that lead to their emission.« less

  16. The FERMI@Elettra free-electron-laser source for coherent X-ray physics: photon properties, beam transport system, and applications

    E-Print Network [OSTI]

    Allaria, Enrico

    2010-01-01T23:59:59.000Z

    C. Svetina, S. Tazzari, M. Zangrando and A. Zholents. C.A 445 59 [25] Svetina, C, Zangrando M, Bianco A, and Cocco D

  17. Scattering parameters of the 3.9 GHz accelerating module in a free-electron laser linac: A rigorous comparison between simulations and measurements

    E-Print Network [OSTI]

    Flisgen, T; Zhang, P; Shinton, I R R; Baboi, N; Jones, R M; van Rienen, U

    2014-01-01T23:59:59.000Z

    This article presents a comparison between measured and simulated scattering parameters in a wide frequency interval for the third harmonic accelerating module ACC39 in the linear accelerator FLASH, located at DESY in Hamburg/Germany. ACC39 is a cryomodule housing four superconducting 3.9? GHz accelerating cavities. Due to the special shape of the cavities (in particular its end cells and the beam pipes) in ACC39, the electromagnetic field in the module is, in many frequency ranges, coupled from one cavity to the next. Therefore, the scattering parameters are determined by the entire string and not solely by the individual cavities. This makes the determination of the scattering properties demanding. As far as the authors can determine, this paper shows for the first time a direct comparison between state-of-the-art simulations and measurements of rf properties of long, complex, and asymmetric structures over a wide frequency band. Taking into account the complexity of the system and various geometrical unk...

  18. A compact 10 kW, 476 MHz solid state radio frequency amplifier for pre-buncher cavity of free electron laser injector linear accelerator

    SciTech Connect (OSTI)

    Mohania, Praveen; Mahawar, Ashish; Shrivastava, Purushottam; Gupta, P. D. [Raja Rammana Centre for Advanced Technology (RRCAT), Indore 452013 (India)] [Raja Rammana Centre for Advanced Technology (RRCAT), Indore 452013 (India)

    2013-09-15T23:59:59.000Z

    A 10 kW, 476 MHz, 0.1% duty cycle solid state RF amplifier system for driving sub-harmonic, pre-buncher cavity of IR-FEL injector LINAC, has been developed at RRCAT. The 10 kW power is achieved by combining output of eight 1400 W amplifier modules using 8-way planar corporate combiner. The solid state amplifier modules have been developed using 50 V RF LDMOS transistors which although meant for push-pull operation are being used in single ended configuration with matching circuit developed on a thin (25 mils), high dielectric constant (9.7), low loss microwave laminate with an aim to have a compact structure. Ease of fabrication, modularity, small size, and low cost are the important features of this design which could be used as a template for low duty cycle medium to high pulsed power UHF amplifier system.

  19. An Infrared Free Electron Laser System for the Proposed Chemical Dynamics Research Laboratory at LBL Based on a 500 MHz Superconducting Linac

    E-Print Network [OSTI]

    Kim, K.-J.

    2011-01-01T23:59:59.000Z

    2]. In addition, the SCRF operates in CW mode, and hencereason behind the choice of SCRF for CDRL-FEL, we ,devoteclearly the need of SCRF technology in achieving the

  20. Design of a Superconducting Linear Accelerator for an Infrared Free Electron Laser of the Proposed Chemical Dynamics Research Laboratory at LBL

    E-Print Network [OSTI]

    Chattopadhyay, S.

    2011-01-01T23:59:59.000Z

    500 MHz buncher is a 4-cell SCRF cavity in which the beam issection consists of two SCRF accelerating modules in whichoperating temperature for the SCRF cavities. A standard, 600

  1. Two-gigawatt burst-mode operation of the intense microwave prototype (IMP) free-electron laser (FEL) for the microwave tokamak experiment (MTX)

    SciTech Connect (OSTI)

    Felker, B.; Allen, S.; Bell, H. [and others

    1993-10-06T23:59:59.000Z

    The MTX explored the plasma heating effects of 140 GHz microwaves from both Gyrotrons and from the IMP FEL wiggler. The Gyrotron was long pulse length (0.5 seconds maximum) and the FEL produced short-pulse length, high-peak power, single and burst modes of 140 GHZ microwaves. Full-power operations of the IMP FEL wiggler were commenced in April of 1992 and continued into October of 1992. The Experimental Test Accelerator H (ETA-II) provided a 50-nanosecond, 6-MeV, 2--3 kAmp electron beam that was introduced co-linear into the IMP FEL with a 140 GHz Gyrotron master oscillator (MO). The FEL was able to amplify the MO signal from approximately 7 kW to peaks consistently in the range of 1--2 GW. This microwave pulse was transmitted into the MTX and allowed the exploration of the linear and non-linear effects of short pulse, intense power in the MTX plasma. Single pulses were used to explore and gain operating experience in the parameter space of the IMP FEL, and finally evaluate transmission and absorption in the MTX. Single-pulse operations were repeatable. After the MTX was shut down burst-mode operations were successful at 2 kHz. This paper will describe the IMP FEL, Microwave Transmission System to MTX, the diagnostics used for calorimetric measurements, and the operations of the entire Microwave system. A discussion of correlated and uncorrelated errors that affect FEL performance will be made Linear and non-linear absorption data of the microwaves in the MTX plasma will be presented.

  2. The FERMI@Elettra free-electron-laser source for coherent X-ray physics: photon properties, beam transport system, and applications

    E-Print Network [OSTI]

    Allaria, Enrico

    2010-01-01T23:59:59.000Z

    of diluted system, and EIS, dedicated to Elastic Scattering.to the Timer part of the EIS beamline (at whose beginning athe LDM, DIPROI or Timex-EIS beamlines that share a number

  3. Terahertz free electron superradiation from mimicking surface plasmons-two electron beams interaction within a 3-mirror quasi-optical cavity

    SciTech Connect (OSTI)

    Zhang, Ya-Xin; Zhou, Y.; Dong, L.; Liu, Sheng-Gang [Terahertz Science and Technology Research Center, School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054 (China)] [Terahertz Science and Technology Research Center, School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054 (China)

    2013-05-27T23:59:59.000Z

    Interaction between mimicking surface plasmons and electron beams provides a good opportunity to develop terahertz (THz) radiation sources. In this paper, such an interaction in a special 3-mirror quasi-optical cavity is presented and explored. The 3-mirror quasi-optical cavity acts as a resonant tunable system, the resonance frequency of which can be tuned by adjusting the distance between mirrors. The study demonstrated THz free electron superradiation from the interaction of mimicking surface plasmons and two electron beams that formed a resonance within the structure, with the 3-mirror cavity enhancing the intensity of superradiation. Moreover, this system can work in the high-harmonic superradiation region with relatively high efficiency and low current density. This concept thus shows the application potential for electron-beam-driven terahertz sources.

  4. Laser ablative synthesis of carbon nanotubes

    DOE Patents [OSTI]

    Smith, Michael W. (Newport News, VA); Jordan, Kevin (Newport News, VA); Park, Cheol (Yorktown, VA)

    2010-03-02T23:59:59.000Z

    An improved method for the production of single walled carbon nanotubes that utilizes an RF-induction heated side-pumped synthesis chamber for the production of such. Such a method, while capable of producing large volumes of carbon nanotubes, concurrently permits the use of a simplified apparatus that allows for greatly reduced heat up and cool down times and flexible flowpaths that can be readily modified for production efficiency optimization. The method of the present invention utilizes a free electron laser operating at high average and peak fluence to illuminate a rotating and translating graphite/catalyst target to obtain high yields of SWNTs without the use of a vacuum chamber.

  5. A proposed high-power UV industrial demonstration laser at CEBAF

    SciTech Connect (OSTI)

    Benson, S.V.; Bisognano, J.J.; Bohn, C.L. [Continuous Electron Beam Accelerator Facility, Newport News, VA (United States)] [and others

    1996-04-01T23:59:59.000Z

    The Laser Processing Consortium, a collaboration of industries, universities, and the Continuous Electron Beam Accelerator Facility (CEBAF) in Newport News, Virginia, has proposed building a demonstration industrial processing laser for surface treatment and micro-machining. The laser is a free-electron laser (FEL) with average power output exceeding 1 kW in the ultraviolet (UV). The design calls for a novel driver accelerator that recovers most of the energy of the exhaust electron beam to produce laser light with good wall-plug efficiency. The laser and accelerator design use technologies that are scalable to much higher power. The authors describe the critical design issues in the laser such as the stability, power handling, and losses of the optical resonator, and the quality, power, and reliability of the electron beam. They also describe the calculated laser performance. Finally progress to date on accelerator development and resonator modeling will be reported.

  6. Substrate-Assisted Laser-Initiated Ejection of Proteins Embedded in Water Films Yusheng Dou, Nicholas Winograd, Barbara J. Garrison,*, and Leonid V. Zhigilei

    E-Print Network [OSTI]

    Zhigilei, Leonid V.

    . The laser energy is deposited solely into the gold substrate at different heating rates. For fast heating are ejected from the film entraining the enkephalin molecule away from the metal surface. For heating in recent experiments performed with a train of picosecond pulses generated by a mid-infrared free- electron

  7. Femtosecond Synchronization of Laser Systems for the LCLS

    SciTech Connect (OSTI)

    Byrd, John; /LBL, Berkeley; Doolittle, Lawrence; /LBL, Berkeley; Huang, Gang; /LBL, Berkeley; Staples, John; /LBL, Berkeley; Wilcox, Russell; /LBL, Berkeley; Arthur, John; /SLAC; Frisch, Josef; /SLAC; White, William; /SLAC

    2012-08-24T23:59:59.000Z

    The scientific potential of femtosecond x-ray pulses at linac-driven free-electron lasers such as the Linac Coherent Light Source is tremendous. Time-resolved pump-probe experiments require a measure of the relative arrival time of each x-ray pulse with respect to the experimental pump laser. An optical timing system based on stabilized fiber links has been developed for the LCLS to provide this synchronization. Preliminary results show synchronization of the installed stabilized links at the sub-20-femtosecond level. We present details of the implementation at LCLS and potential for future development.

  8. The LINAC Coherent Light Source and Radiological Issues During the Commissioning

    SciTech Connect (OSTI)

    Mao, X.S.; Leitner, M.Santana; Vollaire, J.; /SLAC

    2010-08-26T23:59:59.000Z

    The Linac Coherent Light Source (LCLS) at SLAC National Accelerator Laboratory is the world's first X-ray free electron laser (XFEL). Pulses of x-ray laser light from LCLS will be many orders of magnitude brighter and several orders of magnitude shorter than what can be produced by other x-ray sources available in the world. These characteristics will enable frontier new science in many areas. This paper describes the LCLS beam parameters and lay-out. The general radiological issues during commissioning are presented, such as radiation dose rates and integrated doses outside the enclosure. Also, specific radiological issues related to X-ray free electron lasers are discussed. XFEL with high peak power will burn through high-Z materials. The X-ray beam needs to be blocked by stoppers when the downstream areas are occupied. LCLS stoppers feature a piece of boron carbide (B{sub 4}C), 10 mm thick. B{sub 4}C is one of the best materials since it has a low absorption coefficient for X-rays and a high melting temperature. Theoretical calculations indicate that the unfocused fluence of the LCLS XFEL beam should be about one order of magnitude below the damage threshold for bulk B{sub 4}C, for 830 eV FEL radiation. However, these calculations have not been tested experimentally and cannot be validated until LCLS begins providing 830 eV XFEL pulses. This paper describes the test plan for using the initial LCLS radiation to evaluate the survivability of B{sub 4}C and reports the preliminary results. Another major issue for LCLS is the potential radiation damage to the LCLS undulator magnets during operation. TLD dosimeters were installed along the LCLS undulators for each period of two or three weeks. This paper reports the integrated doses along the undulators with and without XFEL generation.

  9. Impact of the spatial laser distribution on photocathode gun operation

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

    Zhou, Feng; Brachmann, Axel; Emma, Paul; Gilevich, Sasha; Huang, Zhirong

    2012-09-01T23:59:59.000Z

    It is widely believed that a drive laser with uniform temporal and spatial laser profiles is required to generate the lowest emittance beam at the photoinjector. However, for a given 3 ps smooth-Gaussian laser temporal profile, our recent simulations indicate that a truncated-Gaussian laser spatial profile produces an electron beam with smaller emittance. The simulation results are qualitatively confirmed by later analytical calculation, and also confirmed by measurements: emittance reduction of ?25% was observed at the linac coherent light source (LCLS) injector with a truncated-Gaussian laser spatial profile at the nominal operating bunch charge of 150 pC. There was a significant secondary benefit—laser transmission through the iris for the truncated-Gaussian profile was about twice that compared to the nearly uniform distribution, which significantly loosens the laser power and quantum efficiency requirements for drive laser system and photocathode. Since February 9, 2012, the drive laser with the truncated-Gaussian spatial distribution has been used for LCLS routine user operations and the corresponding free electron laser power is at least the same as the one when using the nearly uniform spatial profile.

  10. High power laser coupling to carbon nano-tubes and ion Coulomb explosion

    SciTech Connect (OSTI)

    K, Magesh Kumar K; Tripathi, V. K. [Department of Physics, Indian Institute of Technology Delhi, New Delhi 110016 (India)] [Department of Physics, Indian Institute of Technology Delhi, New Delhi 110016 (India)

    2013-09-15T23:59:59.000Z

    Linear and non linear interaction of laser with an array of carbon nanotubes is investigated. The ac conductivity of nanotubes, due to uneven response of free electrons in them to axial and transverse fields, is a tensor. The propagation constant for p-polarization shows resonance at a specific frequency that varies with the direction of laser propagation. It also shows surface plasmon resonance at ?=?{sub p}/?(2), where ?{sub p} is the plasma frequency of free electrons inside a nanotube, assumed to be uniform plasma cylinder. The attenuation constant is also resonantly enhanced around these frequencies. At large laser amplitude, the nanotubes behave as thin plasma rods. As the electrons get heated, the nanotubes undergo hydrodynamic expansion. At an instant when plasma frequency reaches ?{sub p}=?(2)?, the electron temperature rises rapidly and then saturates. For a Gaussian laser beam, the heating rate is maximum on the laser axis and falls off with the distance r from the axis. When the excursion of the electrons ? is comparable or larger than the radius of the nanotube r{sub c}, the nanotubes undergo ion Coulomb explosion. The distribution function of ions turns out to be a monotonically decreasing function of energy.

  11. Femtosecond X-ray Diffraction From Two-Dimensional Protein Crystals

    SciTech Connect (OSTI)

    Frank, Matthias; Carlson, David B.; Hunter, Mark; Williams, Garth J.; Messerschmidt, Marc; Zatsepin, Nadia A.; Barty, Anton; Benner, Henry; Chu, Kaiqin; Graf, Alexander; Hau-Riege, Stefan; Kirian, Rick; Padeste, Celestino; Pardini, Tommaso; Pedrini, Bill; Segelke, Brent; Seibert, M. M.; Spence , John C.; Tsai, Ching-Ju; Lane, Steve M.; Li, Xiao-Dan; Schertler, Gebhard; Boutet, Sebastien; Coleman, Matthew A.; Evans, James E.

    2014-02-28T23:59:59.000Z

    Here we present femtosecond x-ray diffraction patterns from two-dimensional (2-D) protein crystals using an x-ray free electron laser (XFEL). To date it has not been possible to acquire x-ray diffraction from individual 2-D protein crystals due to radiation damage. However, the intense and ultrafast pulses generated by an XFEL permits a new method of collecting diffraction data before the sample is destroyed. Utilizing a diffract-before-destroy methodology at the Linac Coherent Light Source, we observed Bragg diffraction to better than 8.5 Å resolution for two different 2-D protein crystal samples that were maintained at room temperature. These proof-of-principle results show promise for structural analysis of both soluble and membrane proteins arranged as 2-D crystals without requiring cryogenic conditions or the formation of three-dimensional crystals.

  12. SNS Laser Stripping for H- Injection

    SciTech Connect (OSTI)

    V.V. Danilov, Y. Liu, K.B. Beard, V.G. Dudnikov, R.P. Johnson, Michelle D. Shinn

    2009-05-01T23:59:59.000Z

    The ORNL spallation neutron source (SNS) user facility requires a reliable, intense beams of protons. The technique of H- charge exchange injection into a storage ring or synchrotron has the potential to provide the needed beam currents, but it will be limited by intrinsic limitations of carbon and diamond stripping foils. A laser in combination with magnetic stripping has been used to demonstrate a new technique for high intensity proton injection, but several problems need to be solved before a practical system can be realized. Technology developed for use in Free Electron Lasers is being used to address the remaining challenges to practical implementation of laser controlled H- charge exchange injection for the SNS. These technical challenges include (1) operation in vacuum, (2) the control of the UV laser beam to synchronize with the H- beam and to shape the proton beam, (3) the control and stabilization of the Fabry-Perot resonator, and (4) protection of the mirrors from radiation.

  13. Nonlinear Thomson scattering of an ultrashort laser pulse

    SciTech Connect (OSTI)

    Golovinski, P. A., E-mail: golovinski@bk.ru; Mikhin, E. A. [Voronezh State Architectural-Building University (Russian Federation)

    2011-10-15T23:59:59.000Z

    The nonlinear scattering of an ultrashort laser pulse by free electrons is considered. The pulse is described in the 'Mexican hat' wavelet basis. The equation of motion for a charged particle in the field of a plane electromagnetic wave has an exact solution allowing, together with the instant spectrum approximation, the calculation of the intensity of nonlinear Thomson scattering for a high-intensity laser pulse. The spectral distribution of scattered radiation for the entire pulse duration is found by integrating with respect to time. The maximum of the emission spectrum of a free electron calculated in 10{sup 19}-10{sup 21} W/cm{sup 2} fields lies in the UV spectral region between 3 and 12 eV. A part of the continuous spectrum achieves high photon energies. One percent of the scattered energy for the field intensity 10{sup 20} W/cm{sup 2} is concentrated in the range h{omega} > 2.7 Multiplication-Sign 10{sup 2} eV, for a field intensity of 10{sup 21} W/cm{sup 2} in the range h{Omega} > 7.9 Multiplication-Sign 10{sup 2} eV, and for an intensity of 10{sup 22} W/cm{sup 2} in the range h{Omega} > 2.45 Multiplication-Sign 10{sup 5} eV. These results allow us to estimate nonlinear scattering as a source of hard X-rays.

  14. Temperature activated absorption during laser-induced damage: The evolution of laser-supported solid-state absorption fronts

    SciTech Connect (OSTI)

    Carr, C W; Bude, J D; Shen, N; Demange, P

    2010-10-26T23:59:59.000Z

    Previously we have shown that the size of laser induced damage sites in both KDP and SiO{sub 2} is largely governed by the duration of the laser pulse which creates them. Here we present a model based on experiment and simulation that accounts for this behavior. Specifically, we show that solid-state laser-supported absorption fronts are generated during a damage event and that these fronts propagate at constant velocities for laser intensities up to 4 GW/cm{sup 2}. It is the constant absorption front velocity that leads to the dependence of laser damage site size on pulse duration. We show that these absorption fronts are driven principally by the temperature-activated deep sub band-gap optical absorptivity, free electron transport, and thermal diffusion in defect-free silica for temperatures up to 15,000K and pressures < 15GPa. In addition to the practical application of selecting an optimal laser for pre-initiation of large aperture optics, this work serves as a platform for understanding general laser-matter interactions in dielectrics under a variety of conditions.

  15. First Results of the LCLS Laser-Heater System

    SciTech Connect (OSTI)

    Emma, P; Boyce, R.F.; Brachmann, A.; Carr, R.; Decker, F.-J.; Ding, Y.; Dowell, D.; Edstrom, S.; Frisch, J.; Gilevich, S.; Hays, G.; Hering, Ph.; Huang, Z.; Iverson, R.; Levashov, Y.; Loos, H.; Miahnahri, A.; Nuhn, H.-D.; Poling, B.; Ratner, D.; Spampinati, S.; /SLAC

    2011-12-16T23:59:59.000Z

    The Linac Coherent Light Source (LCLS) is an x-ray Free-Electron Laser (FEL) project that has just achieved its first lasing at 1.5 {angstrom} radiation wavelength. The very bright electron beam required to drive this FEL is susceptible to a microbunching instability in the magnetic bunch compressors that may increase the slice energy spread beyond the FEL tolerance. To control the slice energy spread and to suppress the microbunching instability, a laser heater (LH) system is installed in the LCLS injector area at 135 MeV, right before the RF deflector that is used for the time-resolved electron diagnostics. This unique component is used to add a small level of intrinsic energy spread to the electron beam in order to Landau damp the microbunching instability before it potentially breaks up the high brightness electron beam. The system was fully installed and tested in the fall of 2008, and effects of heating on the electron beam and the x-ray FEL were studied during the 2009 commissioning period. The laser heater system is composed of a 4-dipole chicane; a 9-period, planar, permanent-magnet, adjustable-gap undulator at the center of the chicane; one OTR screen on each side of the undulator for electron/laser spatial alignment; and an IR laser (up to 15-MW power) which co-propagates with the electron beam inside the undulator generating a 758-nm energy modulation along the bunch. The final two dipoles of the 4-dipole chicane time-smear this modulation leaving only a thermal-like intrinsic energy spread within the bunch. Table 1 lists the main parameters for this system. The very bright electron beam required for an x-ray free-electron laser (FEL), such as the LCLS, is susceptible to a microbunching instability in the magnetic bunch compressors, prior to the FEL undulator. The uncorrelated electron energy spread in the LCLS can be increased by an order of magnitude to provide strong Landau damping against the instability without degrading the FEL performance. To this end, a 'laser-heater' system has been installed in the LCLS injector, which modulates the energy of a 135-MeV electron bunch with an IR laser beam in a short undulator, enclosed within a four-dipole chicane. The last half of the chicane time-smears the energy modulation leaving an effective thermal energy spread increase. We present the first commissioning results of this system, its operational issues, its impact on the microbunching instability, and finally its effect on the FEL performance.

  16. Page 1Laser Safety Training Laser Institute of America Laser Safety Laser Institute of America

    E-Print Network [OSTI]

    Farritor, Shane

    Page 1Laser Safety Training © Laser Institute of America 1 Laser Safety © Laser Institute of America Laser Safety: Hazards, Bioeffects, and Control Measures Laser Institute of America Gus Anibarro Education Manager 2Laser Safety © Laser Institute of America Laser Safety Overview Laser Safety Accidents

  17. Rescattering effects in laser-assisted electron-atom bremsstrahlung

    E-Print Network [OSTI]

    Zheltukhin, A N; Frolov, M V; Manakov, N L; Starace, Anthony F

    2015-01-01T23:59:59.000Z

    Rescattering effects in nonresonant spontaneous laser-assisted electron-atom bremsstrahlung (LABrS) are analyzed within the framework of time-dependent effective-range (TDER) theory. It is shown that high energy LABrS spectra exhibit rescattering plateau structures that are similar to those that are well-known in strong field laser-induced processes as well as those that have been predicted theoretically in laser-assisted collision processes. In the limit of a low-frequency laser field, an analytic description of LABrS is obtained from a rigorous quantum analysis of the exact TDER results for the LABrS amplitude. This amplitude is represented as a sum of factorized terms involving three factors, each having a clear physical meaning. The first two factors are the exact field-free amplitudes for electron-atom bremsstrahlung and for electron-atom scattering, and the third factor describes free electron motion in the laser field along a closed trajectory between the first (scattering) and second (rescattering) co...

  18. Rescattering effects in laser-assisted electron-atom bremsstrahlung

    E-Print Network [OSTI]

    A. N. Zheltukhin; A. V. Flegel; M. V. Frolov; N. L. Manakov; Anthony F. Starace

    2015-02-01T23:59:59.000Z

    Rescattering effects in nonresonant spontaneous laser-assisted electron-atom bremsstrahlung (LABrS) are analyzed within the framework of time-dependent effective-range (TDER) theory. It is shown that high energy LABrS spectra exhibit rescattering plateau structures that are similar to those that are well-known in strong field laser-induced processes as well as those that have been predicted theoretically in laser-assisted collision processes. In the limit of a low-frequency laser field, an analytic description of LABrS is obtained from a rigorous quantum analysis of the exact TDER results for the LABrS amplitude. This amplitude is represented as a sum of factorized terms involving three factors, each having a clear physical meaning. The first two factors are the exact field-free amplitudes for electron-atom bremsstrahlung and for electron-atom scattering, and the third factor describes free electron motion in the laser field along a closed trajectory between the first (scattering) and second (rescattering) collision events. Finally, a generalization of these TDER results to the case of LABrS in a Coulomb field is discussed.

  19. Adjustment of ablation shapes and subwavelength ripples based on electron dynamics control by designing femtosecond laser pulse trains

    SciTech Connect (OSTI)

    Yuan Yanping; Jiang Lan; Li Xin; Wang Cong [Laser Micro/Nano-Fabrication Laboratory, School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081 (China); Lu Yongfeng [Department of Electrical Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska 68588-0511 (United States)

    2012-11-15T23:59:59.000Z

    A quantum model is proposed to investigate femtosecond laser pulse trains processing of dielectrics by including the plasma model with the consideration of laser particle-wave duality. Central wavelengths (400 nm and 800 nm) strongly impact the surface plasmon field distribution, the coupling field intensity distribution (between the absorbed intensity and the surface plasma), and the distribution of transient localized free electron density in the material. This, in turn, significantly changes the localized transient optical/thermal properties during laser materials processing. The effects of central wavelengths on ablation shapes and subwavelength ripples are discussed. The simulation results show that: (1) ablation shapes and the spacing of subwavelength ripples can be adjusted by localized transient electron dynamics control using femtosecond laser pulse trains; (2) the adjustment of the radii of ablation shapes is stronger than that of the periods of subwavelength ripples.

  20. Demonstration of electron beam focusing by a laser-plasma lens

    E-Print Network [OSTI]

    Thaury, Cédric; Döpp, Andreas; Lehe, Remi; Lifschitz, Agustin; Phuoc, Kim Ta; Gautier, Julien; Goddet, Jean-Philippe; Tafzi, Amar; Flacco, Alessandro; Tissandier, Fabien; Sebban, Stéphane; Rousse, Antoine; Malka, Victor

    2014-01-01T23:59:59.000Z

    Laser-plasma technology promises a drastic reduction of the size of high energy electron accelerators. It could make free electron lasers available to a broad scientific community, and push further the limits of electron accelerators for high energy physics. Furthermore the unique femtosecond nature of the source makes it a promising tool for the study of ultra-fast phenomena. However, applications are hindered by the lack of suitable lens to transport this kind of high-current electron beams, mainly due to their divergence. Here we show that this issue can be solved by using a laser-plasma lens, in which the field gradients are five order of magnitude larger than in conventional optics. We demonstrate a reduction of the divergence by nearly a factor of three, which should allow for an efficient coupling of the beam with a conventional beam transport line.

  1. Second user workshop on high-power lasers at the Linac Coherent Light Source

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

    Heimann, Phil; Glenzer, Siegfried

    2015-05-04T23:59:59.000Z

    The second international workshop on the physics enabled by the unique combination of high-power lasers with the world-class Linac Coherent Light Source (LCLS) free-electron X-ray laser beam was held in Stanford, CA, on October 7–8, 2014. The workshop was co-organized by UC Berkeley, Lawrence Berkeley, Lawrence Livermore, and SLAC National Accelerator Laboratories. More than 120 scientists, including 40 students and postdoctoral scientists who are working in high-intensity laser-matter interactions, fusion research, and dynamic high-pressure science came together from North America, Europe, and Asia. The focus of the second workshop was on scientific highlights and the lessons learned from 16 newmore »experiments that were performed on the Matter in Extreme Conditions (MEC) instrument since the first workshop was held one year ago.« less

  2. Laser Telecommunication timeLaser beam

    E-Print Network [OSTI]

    La Rosa, Andres H.

    Laser Telecommunication Experiment Laser time Laser beam intensity timeLaser beam Laser battery Laser connected to a circuit without a modulator. Bottom graph illustrates what happen when a modulating signal is superimposed to the DC voltage driving the laser Laser beam intensity DC Input voltage DC

  3. Laser microphone

    DOE Patents [OSTI]

    Veligdan, James T. (Manorville, NY)

    2000-11-14T23:59:59.000Z

    A microphone for detecting sound pressure waves includes a laser resonator having a laser gain material aligned coaxially between a pair of first and second mirrors for producing a laser beam. A reference cell is disposed between the laser material and one of the mirrors for transmitting a reference portion of the laser beam between the mirrors. A sensing cell is disposed between the laser material and one of the mirrors, and is laterally displaced from the reference cell for transmitting a signal portion of the laser beam, with the sensing cell being open for receiving the sound waves. A photodetector is disposed in optical communication with the first mirror for receiving the laser beam, and produces an acoustic signal therefrom for the sound waves.

  4. Laser ignition

    DOE Patents [OSTI]

    Early, James W.; Lester, Charles S.

    2004-01-13T23:59:59.000Z

    Sequenced pulses of light from an excitation laser with at least two resonator cavities with separate output couplers are directed through a light modulator and a first polarzing analyzer. A portion of the light not rejected by the first polarizing analyzer is transported through a first optical fiber into a first ignitor laser rod in an ignitor laser. Another portion of the light is rejected by the first polarizing analyzer and directed through a halfwave plate into a second polarization analyzer. A first portion of the output of the second polarization analyzer passes through the second polarization analyzer to a second, oscillator, laser rod in the ignitor laser. A second portion of the output of the second polarization analyzer is redirected by the second polarization analyzer to a second optical fiber which delays the beam before the beam is combined with output of the first ignitor laser rod. Output of the second laser rod in the ignitor laser is directed into the first ignitor laser rod which was energized by light passing through the first polarizing analyzer. Combined output of the first ignitor laser rod and output of the second optical fiber is focused into a combustible fuel where the first short duration, high peak power pulse from the ignitor laser ignites the fuel and the second long duration, low peak power pulse directly from the excitation laser sustains the combustion.

  5. Laser device

    DOE Patents [OSTI]

    Scott, Jill R. (Idaho Falls, ID); Tremblay, Paul L. (Idaho Falls, ID)

    2007-07-10T23:59:59.000Z

    A laser device includes a target position, an optical component separated a distance J from the target position, and a laser energy source separated a distance H from the optical component, distance H being greater than distance J. A laser source manipulation mechanism exhibits a mechanical resolution of positioning the laser source. The mechanical resolution is less than a spatial resolution of laser energy at the target position as directed through the optical component. A vertical and a lateral index that intersect at an origin can be defined for the optical component. The manipulation mechanism can auto align laser aim through the origin during laser source motion. The laser source manipulation mechanism can include a mechanical index. The mechanical index can include a pivot point for laser source lateral motion and a reference point for laser source vertical motion. The target position can be located within an adverse environment including at least one of a high magnetic field, a vacuum system, a high pressure system, and a hazardous zone. The laser source and an electro-mechanical part of the manipulation mechanism can be located outside the adverse environment. The manipulation mechanism can include a Peaucellier linkage.

  6. Laser ignition

    DOE Patents [OSTI]

    Early, James W. (Los Alamos, NM); Lester, Charles S. (San Juan Pueblo, NM)

    2003-01-01T23:59:59.000Z

    In the apparatus of the invention, a first excitation laser or other excitation light source is used in tandem with an ignitor laser to provide a compact, durable, engine deployable fuel ignition laser system. Reliable fuel ignition is provided over a wide range of fuel conditions by using a single remote excitation light source for one or more small lasers located proximate to one or more fuel combustion zones. In a third embodiment, alternating short and long pulses of light from the excitation light source are directed into the ignitor laser. Each of the embodiments of the invention can be multiplexed so as to provide laser light energy sequentially to more than one ignitor laser.

  7. LCLS - The X-ray Laser Has Turned On

    SciTech Connect (OSTI)

    Bergmann, Uwe (Linac Coherent Light Source) [Linac Coherent Light Source

    2010-11-03T23:59:59.000Z

    On April 10, 2009 the Linac Coherent Light Source (LCLS), the world's first hard x-ray free electron laser, was brought to lasing. Producing an x-ray beam with over a billion times higher peak brightness that then most powerful existing syncrotron sources, it marked the beginning of a new era of science. The LCLS pulses arrive at a rate of 60 - 120 Hz in an energy range from 480 eV to 10 keV, with pulse lengths as short as a few fs to about 300 fs. Since October 2009, users have been performing experiments at the LCLS, and currently three of the six planned instruments are available. Although we stand only at the beginning of LCLS science, there is no doubt about the strong sense of early excitement.

  8. Improvements in serial femtosecond crystallography of photosystem II by optimizing crystal uniformity using microseeding procedures

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

    Ibrahim, Mohamed; Chatterjee, Ruchira; Hellmich, Julia; Tran, Rosalie; Bommer, Martin; Yachandra, Vittal K.; Yano, Junko; Kern, Jan; Zouni, Athina

    2015-07-01T23:59:59.000Z

    In photosynthesis, photosystem II (PSII) is the multi-subunit membrane protein complex that catalyzes photo-oxidation of water into dioxygen through the oxygen evolving complex (OEC). To understand the water oxidation reaction, it is important to get structural information about the transient and intermediate states of the OEC in the dimeric PSII core complex (dPSIIcc). In recent times, femtosecond X-ray pulses from the free electron laser (XFEL) are being used to obtain X-ray diffraction (XRD) data of dPSIIcc microcrystals at room temperature that are free of radiation damage. In our experiments at the XFEL, we used an electrospun liquid microjet setup thatmore »requires microcrystals less than 40 ?m in size. In this study, we explored various microseeding techniques to get a high yield of monodisperse uniform-sized microcrystals. Monodisperse microcrystals of dPSIIcc of uniform size were a key to improve the stability of the jet and the quality of XRD data obtained at the XFEL. This was evident by an improvement of the quality of the datasets obtained, from 6.5 Å, using crystals grown without the micro seeding approach, to 4.5 Å using crystals generated with the new method.« less

  9. 7 Å Resolution in Protein 2-Dimentional-Crystal X-Ray Diffraction at Linac Coherent Light Source

    SciTech Connect (OSTI)

    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

    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.

  10. Maximizing Spectral Flux from Self-Seeding Hard X-ray FELs

    E-Print Network [OSTI]

    Yang, Xi

    2013-01-01T23:59:59.000Z

    Fully coherent x-rays can be generated by self-seeding x-ray free-electron lasers (XFELs). Self-seeding by a forward Bragg diffraction (FBD) monochromator has been recently proposed [1] and demonstrated [2]. Characteristic time To of FBD determines the power, spectral, and time characteristics of the FBD seed [3]. Here we show that for a given electron bunch with duration sigma_e the spectral flux of the self-seeding XFEL can be maximized, and the spectral bandwidth can be respectively minimized by choosing To ~ sigma_e/pi and by optimizing the electron bunch delay tau_e. The choices of To and tau_e are not unique. In all cases, the maximum value of the spectral flux and the minimum bandwidth are primarily determined by sigma_e. Two-color seeding takes place To >> sigma_e/\\pi. The studies are performed, for a Gaussian electron bunch distribution with the parameters, close to those used in the short-bunch (sigma_e ~ 5 fs) and long-bunch (sigma_e ~ 20 fs) operation modes of the LCLS XFEL.

  11. Biocavity Lasers

    SciTech Connect (OSTI)

    Gourley, P.L.; Gourley, M.F.

    2000-10-05T23:59:59.000Z

    Laser technology has advanced dramatically and is an integral part of today's healthcare delivery system. Lasers are used in the laboratory analysis of human blood samples and serve as surgical tools that kill, burn or cut tissue. Recent semiconductor microtechnology has reduced the size o f a laser to the size of a biological cell or even a virus particle. By integrating these ultra small lasers with biological systems, it is possible to create micro-electrical mechanical systems that may revolutionize health care delivery.

  12. Laser ignition

    DOE Patents [OSTI]

    Early, James W. (Los Alamos, NM); Lester, Charles S. (San Juan Pueblo, NM)

    2002-01-01T23:59:59.000Z

    In the apparatus of the invention, a first excitation laser or other excitation light source capable of producing alternating beams of light having different wavelengths is used in tandem with one or more ignitor lasers to provide a compact, durable, engine deployable fuel ignition laser system. Reliable fuel ignition is provided over a wide range of fuel conditions by using the single remote excitation light source for pumping one or more small lasers located proximate to one or more fuel combustion zones with alternating wavelengths of light.

  13. Measurements of the LCLS Laser Heater and its impact on the x-ray FEL Performance

    SciTech Connect (OSTI)

    Huang, Zhirong; Brachmann, A.; Decker, F.-J.; Ding, Y.; Dowell, D.; Emma, P.; Frisch, J.; Gilevich, S.; Hays, G.; Hering, Ph.; Iverson, R.; Loos, H.; Miahnahri, A.; Nuhn, H.-D.; Ratner, D.; Stupakov, G.; Turner, J.; Welch, J.; White, W.; Wu, J.; Xiang, D.

    2009-12-17T23:59:59.000Z

    The very bright electron beam required for an x-ray free-electron laser (FEL), such as the Linac Coherent Light Source (LCLS), is susceptible to a microbunching instability in the magnetic bunch compressors, prior to the FEL undulator. The uncorrelated electron energy spread in the LCLS can be increased by an order of magnitude to provide strong Landau damping against the instability without degrading the FEL performance. To this end, a 'laser-heater' system has been installed in the LCLS injector, which modulates the energy of a 135-MeV electron bunch with an IR laser beam in a short undulator, enclosed within a four-dipole chicane. In this paper, we report detailed measurements of laser heater-induced energy spread, including the unexpected self-heating phenomenon when the laser energy is very low. We discuss the suppression of the microbunching instability with the laser heater and its impact on the x-ray FEL performance. We also present the analysis of these experimental results and develop a three-dimensional longitudinal space charge model to explain the self-heating effect.

  14. Laser goniometer

    DOE Patents [OSTI]

    Fairer, George M. (Boulder, CO); Boernge, James M. (Lakewood, CO); Harris, David W. (Lakewood, CO); Campbell, DeWayne A. (Littleton, CO); Tuttle, Gene E. (Littleton, CO); McKeown, Mark H. (Golden, CO); Beason, Steven C. (Lakewood, CO)

    1993-01-01T23:59:59.000Z

    The laser goniometer is an apparatus which permits an operator to sight along a geologic feature and orient a collimated lamer beam to match the attitude of the feature directly. The horizontal orientation (strike) and the angle from horizontal (dip), are detected by rotary incremental encoders attached to the laser goniometer which provide a digital readout of the azimuth and tilt of the collimated laser beam. A microprocessor then translates the square wave signal encoder outputs into an ASCII signal for use by data recording equipment.

  15. Laser Optomechanics

    E-Print Network [OSTI]

    Yang, Weijian; Ng, Kar Wei; Rao, Yi; Chase, Christopher; Chang-Hasnain, Connie J

    2015-01-01T23:59:59.000Z

    Cavity optomechanics explores the coupling between the optical field and the mechanical oscillation to induce cooling and regenerative oscillation in a mechanical oscillator. So far, optomechanics relies on the detuning between the cavity and an external pump laser, where the laser acts only as a power supply. Here, we report a new scheme with mutual coupling between a mechanical oscillator that supports a mirror of a vertical-cavity surface-emitting laser (VCSEL) and the optical field, greatly enhancing the light-matter energy transfer. In this work, we used an ultra-light-weight (130 pg) high-contrast-grating (HCG) mirror in a VCSEL, whose reflectivity spectrum is designed to facilitate strong optomechanical coupling, to demonstrate optomechanically-induced regenerative oscillation of the laser optomechanical cavity with > 550 nm self-oscillation amplitude of the micro-mechanical oscillator, two to three orders of magnitude larger than typical. This new scheme not only offers an efficient approach for high-...

  16. Laser barometer

    SciTech Connect (OSTI)

    Abercrombie, K.R.; Shiels, D.; Rash, T.

    1998-04-01T23:59:59.000Z

    This paper describes an invention of a pressure measuring instrument which uses laser radiation to sense the pressure in an enclosed environment by means of measuring the change in refractive index of a gas - which is pressure dependent.

  17. Tracing direct and sequential two-photon double ionization of D{sub 2} in femtosecond extreme-ultraviolet laser pulses

    SciTech Connect (OSTI)

    Jiang, Y. H.; Kurka, M.; Kuehnel, K. U.; Ergler, Th.; Schroeter, C. D.; Moshammer, R. [Max-Planck-Institut fuer Kernphysik, D-69117 Heidelberg (Germany); Rudenko, A.; Foucar, L. [Max-Planck Advanced Study Group at CFEL, D-22607 Hamburg (Germany); Plesiat, E.; Perez-Torres, J. F.; Martin, F. [Departamento de Quimica C-9, Universidad Autonoma de Madrid, E-28049 Madrid (Spain); Herrwerth, O.; Lezius, M.; Kling, M. F. [Max-Planck-Institut fuer Quantenoptik, D-85748 Garching (Germany); Titze, J.; Jahnke, T.; Doerner, R. [Institut fuer Kernphysik, Universitaet Frankfurt, D-60486 Frankfurt (Germany); Sanz-Vicario, J. L. [Instituto de Fisica, Universidad de Antioquia, Medellin (Colombia); Schoeffler, M.; Tilborg, J. van [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

    2010-02-15T23:59:59.000Z

    Two-photon double ionization (TPDI) of D{sub 2} is studied for 38-eV photons at the Free Electron Laser in Hamburg (FLASH). Based on model calculations, instantaneous and sequential absorption pathways are identified as separated peaks in the measured D{sup +}+D{sup +} fragment kinetic energy release (KER) spectra. The instantaneous process appears at high KER, corresponding to ionization at the molecule's equilibrium distance, in contrast to sequential ionization mainly leading to low-KER contributions. Measured fragment angular distributions are in good agreement with theory.

  18. The Development of the Linac Coherent Light Source RF Gun

    E-Print Network [OSTI]

    Dowell, David H; Lewandowski, James; Limborg-Deprey, Cecile; Li, Zenghai; Schmerge, John; Vlieks, Arnold; Wang, Juwen; Xiao, Liling

    2015-01-01T23:59:59.000Z

    The Linac Coherent Light Source (LCLS) is the first x-ray laser user facility based upon a free electron laser (FEL). In addition to many other stringent requirements, the LCLS XFEL requires extraordinary beam quality to saturate at 1.5 angstroms within a 100 meter undulator.[1] This new light source is using the last kilometer of the three kilometer linac at SLAC to accelerate the beam to an energy as high as 13.6 GeV and required a new electron gun and injector to produce a very bright beam for acceleration. At the outset of the project it was recognized that existing RF guns had the potential to produce the desired beam but none had demonstrated it. This paper describes the analysis and design improvements of the BNL/SLAC/UCLA s-band gun leading to achievement of the LCLS performance goals.

  19. GeV electron beams from a cm-scale accelerator

    E-Print Network [OSTI]

    2006-01-01T23:59:59.000Z

    radiation facilities and free electron lasers, and as modules for high-energy particle physics. Radiofrequency-

  20. Laser barometer

    DOE Patents [OSTI]

    Abercrombie, Kevin R. (Westminster, CO); Shiels, David (Thornton, CO); Rash, Tim (Aurora, CO)

    2001-02-06T23:59:59.000Z

    A pressure measuring instrument that utilizes the change of the refractive index of a gas as a function of pressure and the coherent nature of a laser light to determine the barometric pressure within an environment. As the gas pressure in a closed environment varies, the index of refraction of the gas changes. The amount of change is a function of the gas pressure. By illuminating the gas with a laser light source, causing the wavelength of the light to change, pressure can be quantified by measuring the shift in fringes (alternating light and dark bands produced when coherent light is mixed) in an interferometer.

  1. Amyloid diffraction at XFELs | Stanford Synchrotron Radiation...

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

    April 1, 2015 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Speaker: Meng Liang, LCLS Program Description Amyloid fibers are formed when segments of proteins self-assemble...

  2. Interferometric and schlieren characterization of the plasmas and shock wave dynamics during laser-triggered discharge in atmospheric air

    SciTech Connect (OSTI)

    Wei, Wenfu; Li, Xingwen, E-mail: xwli@mail.xjtu.edu.cn; Wu, Jian; Yang, Zefeng; Jia, Shenli; Qiu, Aici [State Key Laboratory of Electrical Insulation and Power Equipment, Xi'an Jiaotong University, Shaanxi 710049 (China)

    2014-08-15T23:59:59.000Z

    This paper describes our efforts to reveal the underlying physics of laser-triggered discharges in atmospheric air using a Mach-Zehnder interferometer and schlieren photography. Unlike the hemispherical shock waves that are produced by laser ablation, bell-like morphologies are observed during laser-triggered discharges. Phase shifts are recovered from the interferograms at a time of 1000?ns by the 2D fast Fourier transform method, and then the values of the refractive index are deduced using the Abel inversion. An abundance of free electrons is expected near the cathode surface. The schlieren photographs visualize the formation of stagnation layers at ?600?ns in the interaction zones of the laser- and discharge-produced plasmas. Multiple reflected waves are observed at later times with the development of shock wave propagations. Estimations using the Taylor-Sedov self-similar solution indicated that approximately 45.8% and 51.9% of the laser and electrical energies are transferred into the gas flow motions, respectively. Finally, numerical simulations were performed, which successfully reproduced the main features of the experimental observations, and provided valuable insights into the plasma and shock wave dynamics during the laser-triggered discharge.

  3. System and method of infrared matrix-assisted laser desorption/ionization mass spectrometry in polyacrylamide gels

    DOE Patents [OSTI]

    Haglund Jr., Richard F.; Ermer, David R.; Baltz-Knorr, Michelle Lee

    2004-11-30T23:59:59.000Z

    A system and method for desorption and ionization of analytes in an ablation medium. In one embodiment, the method includes the steps of preparing a sample having analytes in a medium including at least one component, freezing the sample at a sufficiently low temperature so that at least part of the sample has a phase transition, and irradiating the frozen sample with short-pulse radiation to cause medium ablation and desorption and ionization of the analytes. The method further includes the steps of selecting a resonant vibrational mode of at least one component of the medium and selecting an energy source tuned to emit radiation substantially at the wavelength of the selected resonant vibrational mode. The medium is an electrophoresis medium having polyacrylamide. In one embodiment, the energy source is a laser, where the laser can be a free electron laser tunable to generate short-pulse radiation. Alternatively, the laser can be a solid state laser tunable to generate short-pulse radiation. The laser can emit light at various ranges of wavelength.

  4. Hydrodynamic model for picosecond propagation of laser-created nanoplasmas

    E-Print Network [OSTI]

    Saxena, Vikrant; Ziaja, Beata; Santra, Robin

    2015-01-01T23:59:59.000Z

    The interaction of a free-electron-laser pulse with a moderate or large size cluster is known to create a quasi-neutral nanoplasma, which then expands on hydrodynamic timescale, i.e., $>1$ ps. To have a better understanding of ion and electron data from experiments derived from laser-irradiated clusters, one needs to simulate cluster dynamics on such long timescales for which the molecular dynamics approach becomes inefficient. We therefore propose a two-step Molecular Dynamics-Hydrodynamic scheme. In the first step we use molecular dynamics code to follow the dynamics of an irradiated cluster until all the photo-excitation and corresponding relaxation processes are finished and a nanoplasma, consisting of ground-state ions and thermalized electrons, is formed. In the second step we perform long-timescale propagation of this nanoplasma with a computationally efficient hydrodynamic approach. In the present paper we examine the feasibility of a hydrodynamic two-fluid approach to follow the expansion of spherica...

  5. Ionization heating in rare-gas clusters under intense XUV laser pulses

    SciTech Connect (OSTI)

    Arbeiter, Mathias; Fennel, Thomas [Institute of Physics, University of Rostock, D-18051 Rostock (Germany)

    2010-07-15T23:59:59.000Z

    The interaction of intense extreme ultraviolet (XUV) laser pulses ({lambda}=32 nm, I=10{sup 11}-10{sup 14} W/cm{sup 2}) with small rare-gas clusters (Ar{sub 147}) is studied by quasiclassical molecular dynamics simulations. Our analysis supports a very general picture of the charging and heating dynamics in finite samples under short-wavelength radiation that is of relevance for several applications of free-electron lasers. First, up to a certain photon flux, ionization proceeds as a series of direct photoemission events producing a jellium-like cluster potential and a characteristic plateau in the photoelectron spectrum as observed in Bostedt et al. [Phys. Rev. Lett. 100, 133401 (2008)]. Second, beyond the onset of photoelectron trapping, nanoplasma formation leads to evaporative electron emission with a characteristic thermal tail in the electron spectrum. A detailed analysis of this transition is presented. Third, in contrast to the behavior in the infrared or low vacuum ultraviolet range, the nanoplasma energy capture proceeds via ionization heating, i.e., inner photoionization of localized electrons, whereas collisional heating of conduction electrons is negligible up to high laser intensities. A direct consequence of the latter is a surprising evolution of the mean energy of emitted electrons as function of laser intensity.

  6. Characterization of Molecular Breakup by Super-Intense, Femtosecond XUV Laser Pulses

    E-Print Network [OSTI]

    Yue, Lun

    2015-01-01T23:59:59.000Z

    We study the breakup of $\\text{H}_2^+$ exposed to super-intense, femtosecond laser pulses with frequencies greater than that corresponding to the ionization potential. By solving the time-dependent Schr\\"{o}dinger equation in an extensive field parameter range, it is revealed that highly nonresonant dissociation channels can dominate over ionization. By considering field-dressed Born-Oppenheimer potential energy curves in the reference frame following a free electron in the field, we propose a simple physical model that characterizes this dissociation mechanism. The model is used to predict control of vibrational excitation, magnitude of the dissociation yields, and nuclear kinetic energy release spectra. Finally, the joint energy spectrum for the ionization process illustrates the energy sharing between the electron and the nuclei and the correlation between ionization and dissociation processes.

  7. High-brightness electron beam evolution following laser-based cleaning of a photocathode

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

    Zhou, F.; Brachmann, A.; Decker, F-J.; Emma, P.; Gilevich, S.; Iverson, R.; Stefan, P.; Turner, J.

    2012-09-01T23:59:59.000Z

    Laser-based techniques have been widely used for cleaning metal photocathodes to increase quantum efficiency (QE). However, the impact of laser cleaning on cathode uniformity and thereby on electron beam quality are less understood. We are evaluating whether this technique can be applied to revive photocathodes used for high-brightness electron sources in advanced x-ray free-electron laser (FEL) facilities, such as the Linac Coherent Light Source (LCLS) at the SLAC National Accelerator Laboratory. The laser-based cleaning was applied to two separate areas of the current LCLS photocathode on July 4 and July 26, 2011, respectively. The QE was increased by 8–10 times upon the laser cleaning. Since the cleaning, routine operation has exhibited a slow evolution of the QE improvement and comparatively rapid improvement of transverse emittance, with a factor of 3 QE enhancement over five months, and a significant emittance improvement over the initial 2–3 weeks following the cleaning. Currently, the QE of the LCLS photocathode is holding constant at about 1.2×10?4 , with a normalized injector emittance of about 0.3???m for a 150-pC bunch charge. With the proper procedures, the laser-cleaning technique appears to be a viable tool to revive the LCLS photocathode. We present observations and analyses for the QE and emittance evolution in time following the laser-based cleaning of the LCLS photocathode, and comparison to the previous studies, the measured thermal emittance versus the QE and comparison to the theoretical model.

  8. BNL | CO2 Laser

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

    CO2 Laser The ATF is one of the only two facilities worldwide operating picosecond, terawatt-class CO2 lasers. Our laser system consists of a picoseconds pulse-injector based on...

  9. Transverse Coherence of the LCLS X-Ray Beam

    SciTech Connect (OSTI)

    Not Available

    2010-12-01T23:59:59.000Z

    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.

  10. GUI Application for ATCA-based LLRF Carrier Board Management

    E-Print Network [OSTI]

    Wychowaniak, Jan; Predki, Pawel; Napieralski, Andrzej

    2011-01-01T23:59:59.000Z

    The Advanced Telecommunications Computing Architecture (ATCA) standard describes an efficient and powerful platform, implementation of which was adopted to be used as a base for control systems in high energy physics. The ATCA platform is considered to be applied for the X-ray Free Electron Laser (X-FEL), being built at Deutsches Electronen- Synchrotron (DESY) in Hamburg, Germany. The Low Level Radio Frequency (LLRF) control system is composed of a few ATCA Carrier Boards. Carrier Board hosts Intelligent Platform Management Controller (IPMC), which is developed in compliance with the PICMG specifications. IPMC is responsible for management and monitoring of sub-modules installed on Carrier Boards and pluggable Advanced Mezzanine Card (AMC) modules. The ATCA Shelf Manager is the main control unit of a single ATCA crate, responsible for all power and fan modules and Carrier Boards installed in ATCA shelf. The device provides a system administrator with a set of control and diagnostic capabilities regarding the ...

  11. Laser Safety Management Policy Statement ............................................................................................................1

    E-Print Network [OSTI]

    Davidson, Fordyce A.

    Laser Safety Management Policy Statement...........................................................2 Laser Users.............................................................................................................2 Unit Laser Safety Officer (ULSO

  12. Laser programs highlights 1994

    SciTech Connect (OSTI)

    NONE

    1994-12-31T23:59:59.000Z

    This report provides highlights of the Lawrence Livermore National Laboratories` laser programs. Laser uses and technology assessment and utilization are provided.

  13. BNL | ATF Laser Safety

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

    be continuously escorted by someone who has such training: The training consists of an eye exam, BNL general laser safety lecture, and formal ATF laser familiarization. Untrained...

  14. Fiber Lasers

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItem NotEnergy,ARMFormsGasReleaseSpeechesHall ATours, Programs and EventsFiber Lasers NIF

  15. Laser Faraday

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12electron 9 5 - -/e),,sandLaser Decontamination ofFaraday

  16. X-ray conversion of ultra-short laser pulses on a solid sample: Role of electron waves excited in the pre-plasma

    SciTech Connect (OSTI)

    Baffigi, F., E-mail: federica.baffigi@ino.it; Cristoforetti, G.; Fulgentini, L.; Giulietti, A.; Koester, P.; Labate, L.; Gizzi, L. A. [Intense Laser Irradiation Laboratory, Istituto Nazionale di Ottica, CNR Campus, Via G. Moruzzi 1, 56124, Pisa (Italy)

    2014-07-15T23:59:59.000Z

    Flat silicon samples were irradiated with 40 fs, 800?nm laser pulses at an intensity at the best focus of 2·10{sup 18} Wcm{sup ?2}, in the presence of a pre-plasma on the sample surface. X-ray emission in the spectral range from 2 to 30?keV was detected inside and outside the plane of incidence, while varying pre-plasma scale length, laser intensity, and polarization. The simultaneous detection of 2? and 3?/2 emission allowed the contributions to the X-ray yield to be identified as originating from laser interaction with either the near-critical density (n{sub c}) region or with the n{sub c}/4 region. In the presence of a moderate pre-plasma, our measurements reveal that, provided the pre-plasma reaches a scale-length of a few laser wavelengths, X-ray emission is dominated by the contribution from the interaction with the under dense plasma, where electron plasma waves can grow, via laser stimulated instabilities, and, in turn, accelerate free electrons to high energies. This mechanism leads also to a clear anisotropy in the angular distribution of the X-ray emission. Our findings can lead to an enhancement of the conversion efficiency of ultra short laser pulses into X-rays.

  17. Longitudinal discharge laser baffles

    DOE Patents [OSTI]

    Warner, B.E.; Ault, E.R.

    1994-06-07T23:59:59.000Z

    The IR baffles placed between the window and the electrode of a longitudinal discharge laser improve laser performance by intercepting off-axis IR radiation from the laser and in doing so reduce window heating and subsequent optical distortion of the laser beam. 1 fig.

  18. Short wavelength laser

    DOE Patents [OSTI]

    Hagelstein, P.L.

    1984-06-25T23:59:59.000Z

    A short wavelength laser is provided that is driven by conventional-laser pulses. A multiplicity of panels, mounted on substrates, are supported in two separated and alternately staggered facing and parallel arrays disposed along an approximately linear path. When the panels are illuminated by the conventional-laser pulses, single pass EUV or soft x-ray laser pulses are produced.

  19. Narrow gap laser welding

    DOE Patents [OSTI]

    Milewski, John O. (Santa Fe, NM); Sklar, Edward (Santa Fe, NM)

    1998-01-01T23:59:59.000Z

    A laser welding process including: (a) using optical ray tracing to make a model of a laser beam and the geometry of a joint to be welded; (b) adjusting variables in the model to choose variables for use in making a laser weld; and (c) laser welding the joint to be welded using the chosen variables.

  20. Narrow gap laser welding

    DOE Patents [OSTI]

    Milewski, J.O.; Sklar, E.

    1998-06-02T23:59:59.000Z

    A laser welding process including: (a) using optical ray tracing to make a model of a laser beam and the geometry of a joint to be welded; (b) adjusting variables in the model to choose variables for use in making a laser weld; and (c) laser welding the joint to be welded using the chosen variables. 34 figs.