Sample records for free-electron laser fel

  1. 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

  2. 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.

  3. 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.

  4. 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

  5. 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.

  6. 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)

  7. 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

  8. 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.

  9. 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

  10. 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

  11. 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~.

  12. 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,

  13. 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

  14. 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

  15. 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

  16. 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...

  17. 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.

  18. 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),

  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. 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

  1. 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.

  2. 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

  3. 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

  4. 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

  5. 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

  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. 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...

  8. 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

  9. 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

  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. 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.

  12. 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

  13. 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...

  14. 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.

  15. 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.

  16. 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.

  17. 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

  18. 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. -

  19. 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.

  20. 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-

  1. 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.

  2. 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

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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

  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. 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.

  10. 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

  11. 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

  12. 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

  13. 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

  14. 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.

  15. 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.

  16. 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

  17. 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.

  18. 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

  19. 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

  20. 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

  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. 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) '

  6. 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.

  7. 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

  8. 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

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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

  16. Suppression of microbunching instability using bending magnets in FEL linacs

    E-Print Network [OSTI]

    Qiang, Ji

    2014-01-01T23:59:59.000Z

    using bending magnets in FEL linacs Ji Qiang, Chad E.for free electron laser (FEL) radiation. In this letter, weaccelerators for next generation FEL light sources. Instead

  17. 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

  18. 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.

  19. 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.

  20. 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

  1. 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.

  2. 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

  3. 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.

  4. 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.

  5. 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

  6. 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.

  7. 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.

  8. 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

  9. 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-

  10. 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.

  11. 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...

  12. 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.

  13. 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.

  14. 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).

  15. 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.

  16. 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...

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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...

  2. 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.

  3. 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.

  4. 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.

  5. 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

  6. 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.

  7. 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...

  8. 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.

  9. 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.

  10. 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

  11. 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

  12. 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.

  13. 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

  14. 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

  15. 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

  16. 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

  17. 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

  18. 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

  19. 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

  20. 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,

  1. 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

  2. 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

  3. 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,

  4. 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.

  5. 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

  6. 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

  7. 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

  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

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

  9. 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

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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...

  15. FEL fr Fussgnger FEL fr Fussgnger Dirk.Noelle@desy.deDirk.Noelle@desy.de

    E-Print Network [OSTI]

    FEL für Fussgänger FEL für Fussgänger Dirk Nölle DESY, MDI 9-2579 Dirk ein Free-Electron-Laser? ­ Klassischer" Laser und FEL­ ,,Klassischer Laser und FEL ­ Eine kleiner (historischer) Überblick ­ Das Funktionsprinzip ­ Beispiele für verschiedene FEL Typenp yp ­ SASE 2 #12;TESLA

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  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. Microsoft Word - FEL theory -É

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

    FOR A HIGH GAIN FEL N. A. Vinokurov * Introduction The theory of a high gain free electron laser (FEL) is now well developed (e.g., see 1). In this paper I derive the...

  2. 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

  3. 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.

  4. 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

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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

  11. 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.

  12. 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.

  13. 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.

  14. 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

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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

  20. 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

  1. 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.

  2. 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.

  3. 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.

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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

  9. 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",

  10. 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

  11. 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

  12. 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

  13. 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.

  14. 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.

  15. 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...

  16. Locking Lasers to RF in an Ultra Fast FEL

    E-Print Network [OSTI]

    Wilcox, R.

    2011-01-01T23:59:59.000Z

    Lasers to RF in an Ultrafast FEL R. B . Wilcox, G . Huang,the X-ray pulses from the FEL. The phase-locked loop on the

  17. 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.

  18. 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.

  19. 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...

  20. 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.

  1. Bendable Focusing X-Ray Optics for the ALS and the LCLS/FEL: Design, Metrology, and Performance

    E-Print Network [OSTI]

    Yashchuk, V. V.

    2010-01-01T23:59:59.000Z

    Optics for the ALS and the LCLS/FEL: Design, Metrology, andLCLS) x-ray free electron laser (FEL) at the Stanford LinearKB mirrors used at the SLAC/FEL AMO beamline. Two mirrors

  2. 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.

  3. 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 $B_0 leq 10^{-2} textrm{T}$.

  4. 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

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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

  13. 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.

  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. 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

  17. 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...

  18. 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.

  19. 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

  20. 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.

  1. 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.

  2. 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.

  3. 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}.

  4. 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...

  5. 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

  6. 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.

  7. 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.

  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. 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.

  10. 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

  11. 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

  12. 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

  13. 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

  14. 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

  15. 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.

  16. 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.

  17. 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...

  18. 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....

  19. 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...

  20. 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.

  1. 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.

  2. 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.

  3. 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

  4. Bendable Focusing X-Ray Optics for the ALS and the LCLS/FEL: Design, Metrology, and Performance

    E-Print Network [OSTI]

    Yashchuk, V. V.

    2010-01-01T23:59:59.000Z

    Optics for the ALS and the LCLS/FEL: Design, Metrology, andwas performed in support of the AMO/LCLS project at SLAC. *Coherent Light Source (LCLS) x-ray free electron laser (FEL)

  5. FIRST LASING AT 32 NM OF THE VUV-FEL AT DESY S. Schreiber

    E-Print Network [OSTI]

    FIRST LASING AT 32 NM OF THE VUV-FEL AT DESY S. Schreiber , DESY, Hamburg, Germany for the VUV-FEL team Abstract The VUV-FEL is a free electron laser user facility being commissioned at DESY. It is based on the TTF-FEL, which was in operation until end of 2002 providing a photon beam for two pilot

  6. THE INJECTOR OF THE VUV-FEL AT DESY S. Schreiber

    E-Print Network [OSTI]

    THE INJECTOR OF THE VUV-FEL AT DESY S. Schreiber , DESY, Hamburg, Germany for the VUV-FEL team Abstract The VUV-FEL is a free electron laser user facility be- ing commissioned at DESY in Hamburg, and diagnostic sections. The good performance of the injector was crucial for the first lasing of the VUV-FEL

  7. 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.

  8. 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.

  9. 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.

  10. IMPROVED OPERATION OF THE TTF PHOTOINJECTOR FOR FEL S. Schreiber

    E-Print Network [OSTI]

    IMPROVED OPERATION OF THE TTF PHOTOINJECTOR FOR FEL OPERATION S. Schreiber , J.-P. Carneiro, Ch. Abstract The RF gun based photoinjector of the TTF Free Elec- tron Laser (TTF-FEL) at DESY has been various experiments for the TESLA project, the photoinjector is used to drive the TTF- FEL free electron

  11. Measurements of the Transverse Emittance at the VUV-FEL

    E-Print Network [OSTI]

    Measurements of the Transverse Emittance at the VUV-FEL Diploma Thesis by Florian L¨ohl submitted), Hamburg DESY-THESIS 2005-014 TESLA-FEL 2005-03 Hamburg, July 2005 Abstract The TESLA Test Facility (TTF) linear accelerator (linac) at DESY has been extended to drive a new Free Electron Laser facility (VUV-FEL

  12. CHARACTERIZATION OF ORBITAL ANGULAR MOMENTUM MODES IN FEL RADIATION

    E-Print Network [OSTI]

    Brookhaven National Laboratory

    CHARACTERIZATION OF ORBITAL ANGULAR MOMENTUM MODES IN FEL RADIATION E. Hemsing , G. Andonian, J singularity on axis. Here we discuss current efforts to characterize the mode content of the VISA FEL through are discussed. INTRODUCTION Free-electron lasers (FELs) have long been used as tun- able sources of coherent

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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...

  18. 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.

  19. 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.

  20. 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...

  1. 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.

  2. 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.).

  3. 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.

  4. 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.

  5. 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.

  6. 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

  7. 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...

  8. 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.

  9. 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.

  10. 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.

  11. ANALYTIC MODEL OF HARMONIC GENERATION IN THE LOW-GAIN FEL REGIME

    E-Print Network [OSTI]

    Wurtele, Jonathan

    ANALYTIC MODEL OF HARMONIC GENERATION IN THE LOW-GAIN FEL REGIME G. Penn, M. Reinsch, J.S. Wurtele , LBNL, Berkeley, CA 94720, USA Abstract Harmonic generation using free electron lasers (FELs) requires with simulation results using the FEL code GENESIS, both for single stages of harmonic generation and for the LUX

  12. Wakefield Induced Correlated Energy Spread and Emittance Growth at TTF FEL

    E-Print Network [OSTI]

    1 Wakefield Induced Correlated Energy Spread and Emittance Growth at TTF FEL Feng ZHOU DESY) at DESY. During FEL operations, the longitudinal and transverse wakefields which are generated by vacuum and emittance growth at the TTF FEL of phase I and II. 1 Introduction The Free Electron Laser at the TESLA Test

  13. TRANSVERSE ELECTRON BEAM DIAGNOSTICS AT THE VUV-FEL AT K. Honkavaara

    E-Print Network [OSTI]

    TRANSVERSE ELECTRON BEAM DIAGNOSTICS AT THE VUV-FEL AT DESY K. Honkavaara , F. L¨oehl, Hamburg. Catani, A. Cianchi, INFN-Roma2, 00133 Roma, Italy Abstract The VUV-FEL is a new free electron laser user tools and methods. At the VUV-FEL the transverse distribution of the electron beam is measured using

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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

  7. 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.

  8. 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

  9. 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...

  10. Design of an XUV FEL Driven by the Laser-Plasma Accelerator at the LBNL LOASIS Facility

    E-Print Network [OSTI]

    Schroeder, Carl B.; Fawley, W.M.; Esarey, Eric; Leemans, W.P.

    2006-01-01T23:59:59.000Z

    Table 2 shows the expected FEL performance employing a 31-nmDESIGN OF AN XUV FEL DRIVEN BY THE LASER-PLASMA ACCELERATORa design for a compact FEL source of ultra- fast, high-

  11. 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.

  12. 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

  13. LUNEX5: A FRENCH FEL TEST FACILITY LIGHT SOURCE PROPOSAL A. Loulergue, C. Benabderrahmane, M. Bessire, P. Betinelli, F. Bouvet, A. Buteau, L. Cassinari,

    E-Print Network [OSTI]

    Boyer, Edmond

    LUNEX5: A FRENCH FEL TEST FACILITY LIGHT SOURCE PROPOSAL A. Loulergue, C. Benabderrahmane, M is a new Free Electron Laser (FEL) source project aimed at delivering short and coherent X-ray pulses seeded FEL operations aiming at producing higher coherence and energetic X-rays for the pilot user

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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

  20. 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.

  1. 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 (

  2. 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

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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

  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. 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...

  10. 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.

  11. 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 (

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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...

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

    E-Print Network [OSTI]

    Wurtele, Jonathan

    Performance study of a soft X-ray harmonic generation FEL seeded with an EUV laser pulse M. Gullans electron laser (FEL) using a low-power extreme ultraviolet (EUV) pulse as an input seed is investigated generation schemes. It is found that, for reasonable beam parameters, robust FEL performance can be obtained

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. SEMINARI FEL: Aula Grassano alle ore 14:30 Martedi' 13 Gennaio : Introduzione alla teoria del laser ad elettroni liberi.

    E-Print Network [OSTI]

    Morante, Silvia

    SEMINARI FEL: Aula Grassano alle ore 14:30 Martedi' 13 Gennaio : Introduzione alla teoria del laser particelle/radiazione nei FEL con il codice di simulazione Perseo. Saranno presentati alcuni esempi pratici Ricerca ENEA di Frascati che è lo sviluppatore di uno dei codici di simulazione per i FEL (Perseo) e

  5. 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.

  6. 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.

  7. 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...

  8. 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

  9. 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.

  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. 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. Transverse-coherence properties of the FEL at the LCLS

    SciTech Connect (OSTI)

    Ding, Yuantao

    2010-09-02T23:59:59.000Z

    The recently commissioned Linac Coherent Light Source is an x-ray free-electron laser at the SLAC National Accelerator Laboratory, which is now operating at x-ray wavelengths of 20-1.2 Angstrom with peak brightness nearly ten orders of magnitude beyond conventional synchrotron sources. Understanding of coherence properties of the radiation from SASE FELs at LCLS is of great practical importance for some user experiments. We present the numerical analysis of the coherence properties at different wavelengths based on a fast algorithmusing ideal and start-end simulated FEL fields. The sucessful commissioning and operation of the linac coherent light source (LCLS) [1] has demonstrated that the x-ray free-electron laser (FEL) has come of age; these types of x-ray sources are poised to revolutionize the ultra-fast x-ray sciences. The LCLS and other hard x-ray FELs under construction are based on the principle of self-amplified spontaneous emission (SASE) [2, 3], where the amplification process starts from the shot noise in the electron beam. A large number of transverse radiation modes are also excited when the electron beam enters the undulator. The FEL collective instability in the electron beam causes the modulation of the electron density to increase exponentially, and after sufficient undulator distances, a single transverse mode starts to dominate. As a result, SASE FEL is almost fully coherent in the transverse dimension. Understanding of transverse coherence properties of the radiation from SASE FELs is of great practical importance. The longitudinal coherence properties of SASE FELs have been studied before [4]. Some studies on the transverse coherence can be found in previous papers, for example, in ref. [5, 6, 7, 8, 9]. In this paper, we first discuss a new numerical algorithm based on Markov chain Monte Carlo techniques to calculate the FEL transverse coherence. Then we focus on the numerical analysis of the LCLS FEL transverse coherence.

  20. 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.

  1. 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}.

  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. 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.

  4. Microbunching Instability Effect Studies and Laser Heater Optimization for the SPARX FEL Accelerator

    SciTech Connect (OSTI)

    Vaccarezza, C.; Chiadroni, E.; Ferrario, M.; Giannessi, L.; Quattromini, M.; Ronsivalle, C.; Venturini, C.; Migliorati, M.; Dattoli, G.

    2010-05-23T23:59:59.000Z

    The effects of microbunching instability for the SPARX accelerator have been analyzed by means of numerical simulations. The laser heater counteracting action has been addressed in order to optimize the parameters of the compression system, either hybrid RF plus magnetic chicane or only magnetic, and possibly enhance the FEL performance.

  5. 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.

  6. 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

  7. 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.

  8. 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.

  9. 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.

  10. Microbunching Instability Effect Studies and Laser Heater Optimization for the SPARX FEL Accelerator

    E-Print Network [OSTI]

    Vaccarezza, C.

    2010-01-01T23:59:59.000Z

    OPTIMIZATION FOR THE SPARX FEL ACCELERATOR * C. Vaccarezza,and possibly enhance the FEL performance. delivered to theinstability effect for the SPARX FEL. Table 1: Electron beam

  11. 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.

  12. 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

  13. 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.

  14. FUTURE FEL STUDIES AT THE VISA EXPERIMENT G. Andonian, M. Dunning, A. Murokh, C. Pellegrini, S. Reiche, J. Rosenzweig,

    E-Print Network [OSTI]

    Brookhaven National Laboratory

    amplified spontaneoous emission (SASE) free electron laser. A proposal to obtain ultra- short pulses [4 and diagnosis of ultra-short pulses is of great importance to the FEL community. The generation of femtosecond long, °Angstrom wavelength ra- diation will open doors to a myriad of scientific endeavors at ultra-short

  15. Experimental Test of Hole-Coupled FEL Resonator Designs Using a CW-HeNe Laser

    E-Print Network [OSTI]

    Leemans, W.P.

    2011-01-01T23:59:59.000Z

    Proc. 14 th International FEL Conference, Kobe, Japan, 23-24Test of Hole-Coupled FEL Resonator Designs Using a CW-HeNeuse of hole-coupling for FEL's are: I) reasonable coupling

  16. 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.

  17. 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

  18. 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.

  19. 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.

  20. 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,

  1. 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...

  2. 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.

  3. 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

  4. 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.

  5. Self-seeded injection-locked FEL amplifer

    DOE Patents [OSTI]

    Sheffield, Richard L. (Los Alamos, NM)

    1999-01-01T23:59:59.000Z

    A self-seeded free electron laser (FEL) provides a high gain and extraction efficiency for the emitted light. An accelerator outputs a beam of electron pulses to a permanent magnet wiggler having an input end for receiving the electron pulses and an output end for outputting light and the electron pulses. An optical feedback loop collects low power light in a small signal gain regime at the output end of said wiggler and returns the low power light to the input end of the wiggler while outputting high power light in a high signal gain regime.

  6. 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

  7. Optical Fibre Dosimeter for SASE FEL Undulators

    E-Print Network [OSTI]

    Körfer, M

    2003-01-01T23:59:59.000Z

    Single pass Free Electron Lasers (FELs) based on self-amplified spontaneous emission (SASE) are developed for high brightness and short wavelength applications. They use permanent magnet undulators which are radiation sensitive devices. During accelerator commissioning beam losses can appear anywhere along the undulator line. To avoid damage of the permanent magnets due to radiation, an optical fibre dosimeter system can be used. The increase of absorption caused by ionizing radiation is measured in radiation sensitive optical fibers. The dose system enables relatively fast particle loss tuning during accelerator operation and allows the monitoring of the accumulated dose. Dose measurements in narrow gaps which are inaccessible for any other (online) dosimeter type become possible. The electromagnetic insensitivity of optical fibre sensor is an advantage of applications in strong magnetic undulator fields. At each location the light absorption is measured by using an optical power-meter. The dynamic range is ...

  8. Method of Linear Invariants for description of beam dynamics of FEL undulator

    E-Print Network [OSTI]

    A. Angelow; D. Trifonov; V. Angelov; H. Hristov

    2008-05-23T23:59:59.000Z

    We propose a new model for description of electrons beam dynamics in Free Electron Laser (FEL) undulator, based on the method of linear time-dependent invariants of quantum-mechanical charge particle. The magnetic field has periodic structure along the undulator. For this problem, described by time-dependent quadratic Hamiltonian, we obtain exact solution. The time-evolutions of the tree quantum fluctuations: covariance cov(q,p), var(q) and var(p) for the charge particle in this case are also determined. This research will help to optimize the FEL undulator: for example, using a 2.5 GeV linear electron accelerator it will be possible to emit radiation at 1.5 nm and shorter length. This method could be applicable also to any device with periodic structure of applied field (e.g. Tokamak, cyclic accelerators) for the case of charge non-relativistic quantum particles.

  9. MEASURING FEL RADIATION PROPERTIES AT VISA-FEL A. Murokh*, R...

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

    Stanford, CA 94309 Abstract The VISA (Visible to Infrared SASE Amplifier) SASE free electron laser has been successfully operated at the Accelerator Test Facility (ATF) at BNL....

  10. 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.

  11. An analysis of the saturation of a high gain FEL

    SciTech Connect (OSTI)

    Gluckstern, R.L.; Okamoto, Hiromi (Maryland Univ., College Park, MD (United States). Dept. of Physics); Krinsky, S. (Brookhaven National Lab., Upton, NY (United States))

    1992-12-01T23:59:59.000Z

    We study the saturated state of an untapered free electron laser in the Compton regime, arising after exponential amplification of an initial low level of radiation by an initially monoenergetic, unbunched electron beam. The saturated state of the FEL is described by oscillations about an equilibrium state. Using the two invariants of the motion, and certain assumptions motivated by computer simulations, we provide approximate analytic descriptions of the radiation field and electron distribution in the saturation regime. We first consider a one-dimensional approximation, and later extend our approach to treat an electron beam of finite radial extent. Of note is a result on the radiated power in the case of an electron beam with small radius.

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

    SciTech Connect (OSTI)

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

    2011-08-16T23:59:59.000Z

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

  13. 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.

  14. 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

  15. PROSPECTS FOR THE FEL

    E-Print Network [OSTI]

    Sessler, A.M.

    2008-01-01T23:59:59.000Z

    et aI, "Proposal for a Compact FEL With Electromagnetic WaveSuperradiance in the High-Gain FEL, Nucl. Instr. and MethodsProc. of the 10th Inter. FEL Conference, Lawrence Livermore

  16. TESLA-FEL 2003-04 Waveguide Monitors -a New Type of Beam Position

    E-Print Network [OSTI]

    TESLA-FEL 2003-04 Waveguide Monitors - a New Type of Beam Position Monitors for the TTF FEL U. Hahn Laser (FEL) at the TESLA Test Facilty (TTF) requires the electron trajectory to be aligned bench in the laboratory and with beam. TTF FEL measurement results are also presented and possible

  17. 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.

  18. Experimental Verification of the Chemical Sensitivity of Two-Site Double Core-Hole States Formed by an X-ray FEL

    E-Print Network [OSTI]

    Salen, P; Schmidt, H T; Thomas, R D; Larsson, M; Feifel, R; Piancastelli, M N; Fang, L; Murphy, B; Osipov, T; Berrah, N; Kukk, E; Ueda, K; Bozek, J D; Bostedt, C; Wada, S; Richter, R; Feyer, V; Prince, K C

    2012-01-01T23:59:59.000Z

    We have performed X-ray two-photon photoelectron spectroscopy (XTPPS) using the Linac Coherent Light Source (LCLS) X-ray free-electron laser (FEL) in order to study double core-hole (DCH) states of CO2, N2O and N2. The experiment verifies the theory behind the chemical sensitivity of two-site (ts) DCH states by comparing a set of small molecules with respect to the energy shift of the tsDCH state and by extracting the relevant parameters from this shift.

  19. 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...

  20. Production and Detection of Axion-Like Particles at the VUV-FEL: Letter of Intent

    E-Print Network [OSTI]

    Ulrich Koetz; Andreas Ringwald; Thomas Tschentscher

    2006-06-26T23:59:59.000Z

    Recently, the PVLAS collaboration has reported evidence for an anomalously large rotation of the polarization of light generated in vacuum in the presence of a transverse magnetic field. This may be explained through the production of a new light spin-zero particle coupled to two photons. In this Letter of Intent, we propose to test this hypothesis by setting up a photon regeneration experiment which exploits the photon beam of the Vacuum-UltraViolet Free-Electron Laser VUV-FEL, sent along the transverse magnetic field of a linear arrangement of dipole magnets of size B L ~ 30 Tm. The high photon energies available at the VUV-FEL increase substantially the expected photon regeneration rate in the mass range implied by the PVLAS anomaly, in comparison to the rate expected at visible lasers of similar power. We find that the particle interpretation of the PVLAS result can be tested within a short running period. The pseudoscalar vs. scalar nature can be determined by varying the direction of the magnetic field with respect to the laser polarization. The mass of the particle can be measured by running at different photon energies. The proposed experiment offers a window of opportunity for a firm establishment or exclusion of the particle interpretation of the PVLAS anomaly before other experiments can compete.

  1. 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://

  2. 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

  3. 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

  4. 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.

  5. Feasibility of an XUV FEL Oscillator Driven by a SCRF Linear Accelerator

    SciTech Connect (OSTI)

    Lumpkin, A. H.; Freund, H. P.; Reinsch, M.

    2014-01-01T23:59:59.000Z

    The Advanced Superconducting Test Accelerator (ASTA) facility is currently under construction at Fermi National Accelerator Laboratory. Using a1-ms-long macropulse composed of up to 3000 micropulses, and with beam energies projected from 45 to 800 MeV, the possibility for an extreme ultraviolet (XUV) free-electron laser oscillator (FELO) with the higher energy is evaluated. We have used both GINGER with an oscillator module and the MEDUSA/OPC code to assess FELO saturation prospects at 120 nm, 40 nm, and 13.4 nm. The results support saturation at all of these wavelengths which are also shorter than the demonstrated shortest wavelength record of 176 nm from a storage-ring-based FELO. This indicates linac-driven FELOs can be extended into this XUV wavelength regime previously only reached with single-pass FEL configurations.

  6. Design of an XUV FEL Driven by the Laser-Plasma Accelerator at the LBNL LOASIS Facility

    E-Print Network [OSTI]

    Schroeder, Carl B.; Fawley, W.M.; Esarey, Eric; Leemans, W.P.

    2006-01-01T23:59:59.000Z

    laser system to focus ultra-short (?30 fs) laser pulses ofLASER-PLASMA ACCELERATOR The LOASIS Laboratory at LBNL presently produces ultra-short (short-pulse laser driver, making such a source ideal for ultra-

  7. Design of an XUV FEL Driven by the Laser-Plasma Accelerator at the LBNL LOASIS Facility

    E-Print Network [OSTI]

    Schroeder, Carl B.; Fawley, W.M.; Esarey, Eric; Leemans, W.P.

    2006-01-01T23:59:59.000Z

    laser system to focus ultra-short (?30 fs) laser pulses ofdrive laser pulse, enabling pump- probe studies in ultra-used an ultra- intense ?10 19 W/cm 2 laser pulse focused on

  8. TESLA-FEL Report 2005-06 DIGITAL LOW LEVEL RF CONTROL SYSTEM FOR THE DESY TTF

    E-Print Network [OSTI]

    TESLA-FEL Report 2005-06 DIGITAL LOW LEVEL RF CONTROL SYSTEM FOR THE DESY TTF VUV-FEL LINAC Valeri Electron Laser (VUV-FEL) Linac each klystron supplies RF power to up to 32 cavities. The superconducting. The VUV-FEL Linac RF control system employs a completely digital feedback system to provide flexibility

  9. Dielectric Wakefield Accelerator to drive the future FEL Light Source.

    SciTech Connect (OSTI)

    Jing, C.; Power, J.; Zholents, A. (Accelerator Systems Division (APS)); ( HEP); (LLC)

    2011-04-20T23:59:59.000Z

    X-ray free-electron lasers (FELs) are expensive instruments and a large part of the cost of the entire facility is driven by the accelerator. Using a high-energy gain dielectric wake-field accelerator (DWA) instead of the conventional accelerator may provide a significant cost saving and reduction of the facility size. In this article, we investigate using a collinear dielectric wakefield accelerator to provide a high repetition rate, high current, high energy beam to drive a future FEL x-ray light source. As an initial case study, a {approx}100 MV/m loaded gradient, 850 GHz quartz dielectric based 2-stage, wakefield accelerator is proposed to generate a main electron beam of 8 GeV, 50 pC/bunch, {approx}1.2 kA of peak current, 10 x 10 kHz (10 beamlines) in just 100 meters with the fill factor and beam loading considered. This scheme provides 10 parallel main beams with one 100 kHz drive beam. A drive-to-main beam efficiency {approx}38.5% can be achieved with an advanced transformer ratio enhancement technique. rf power dissipation in the structure is only 5 W/cm{sup 2} in the high repetition rate, high gradient operation mode, which is in the range of advanced water cooling capability. Details of study presented in the article include the overall layout, the transform ratio enhancement scheme used to increase the drive to main beam efficiency, main wakefield linac design, cooling of the structure, etc.

  10. Design of an XUV FEL Driven by the Laser-Plasma Accelerator at the LBNL LOASIS Facility

    E-Print Network [OSTI]

    Schroeder, Carl B.; Fawley, W.M.; Esarey, Eric; Leemans, W.P.

    2006-01-01T23:59:59.000Z

    Ti:Sapphire laser system to focus ultra-short (?30 fs) laserLASER-PLASMA ACCELERATOR The LOASIS Laboratory at LBNL presently produces ultra-short (laser-plasma inter- action lengths. These LWFA-produced electron beams are high current (?10 kA) and ultra-short (

  11. Greenfield FELs John Galayda, SLAC

    E-Print Network [OSTI]

    coverage (fundamental) 3 (5)1 (8)# FEL undulators 2012 (?)2009 (2013)Operation start TESLA (upgrade) LCLS (upgrade) X-ray FEL Projects in Preconstruction #12;Status of X-ray FELs in 2015 · LCLS and TESLA FEL ­ Self-seeding ­ Ultrashort pulse · HGHG scheme #12;SASE FEL for 30 keV · LCLS reference parameters: =

  12. EDITED--LS-332-DWA_FEL_August16

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

    32 August 2012 A Compact Soft X-ray Free-Electron Laser Facility based on a Dielectric Wakefield Accelerator C. Jing, P. Schoessow, A. Kanareykin, Euclid Techlabs LLC, Solon, OH...

  13. Streaking spectroscopy for femtosecond applications and FEL developmen...

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

    these tools we have implemented an all-optical synchronization network at the free-electron laser FLASH, where facility-wide synchronization to better than 30 fs was achieved...

  14. Design of an XUV FEL Driven by the Laser-Plasma Accelerator at the LBNL LOASIS Facility

    E-Print Network [OSTI]

    Schroeder, Carl B.; Fawley, W.M.; Esarey, Eric; Leemans, W.P.

    2006-01-01T23:59:59.000Z

    A445 (2000) 59. [13] W. M. Fawley, LBNL Technical Report No.LBNL-49625 (2002); see also paper MOPPH073, theseLASER-PLASMA ACCELERATOR AT THE LBNL LOASIS FACILITY ? C. B.

  15. Freie Elektronenlaser VUV-FEL Freie Elektronenlaser VUV-FEL

    E-Print Network [OSTI]

    Freie Elektronenlaser VUV-FEL Freie Elektronenlaser VUV-FEL Nach der Inbetriebnahme des neuen Beschleunigungsmodulen kann eine Strahlenergie von etwa 730 MeV erreicht werden. Am 14. Januar wurde zum ersten Mal FEL einem FEL erzeugt wurde. Das Experimentierprogramm f¨ur externe Nutzer be- gann im Sommer 2005 mit der

  16. TESLA FEL-Report 1996-10 TESLA FEL-Report 1996-10

    E-Print Network [OSTI]

    #12;TESLA FEL-Report 1996-10 #12;TESLA FEL-Report 1996-10 #12;TESLA FEL-Report 1996-10 #12;TESLA FEL-Report 1996-10 #12;TESLA FEL-Report 1996-10 #12;TESLA FEL-Report 1996-10 #12;TESLA FEL-Report 1996-10 #12;TESLA FEL-Report 1996-10 #12;TESLA FEL-Report 1996-10 #12;TESLA FEL-Report 1996-10 #12;TESLA FEL

  17. TESLA FEL-Report 1996-13 TESLA FEL-Report 1996-13

    E-Print Network [OSTI]

    TESLA FEL-Report 1996-13 #12;TESLA FEL-Report 1996-13 #12;TESLA FEL-Report 1996-13 #12;TESLA FEL-Report 1996-13 #12;TESLA FEL-Report 1996-13 #12;TESLA FEL-Report 1996-13 #12;TESLA FEL-Report 1996-13 #12;TESLA FEL-Report 1996-13 #12;TESLA FEL-Report 1996-13 #12;TESLA FEL-Report 1996-13 #12;TESLA FEL

  18. TESLA FEL-Report 2000-02 TESLA FEL-Report 2000-02

    E-Print Network [OSTI]

    TESLA FEL-Report 2000-02 #12;TESLA FEL-Report 2000-02 #12;TESLA FEL-Report 2000-02 #12;TESLA FEL-Report 2000-02 #12;TESLA FEL-Report 2000-02 #12;TESLA FEL-Report 2000-02 #12;TESLA FEL-Report 2000-02 #12;TESLA FEL-Report 2000-02 #12;TESLA FEL-Report 2000-02 #12;TESLA FEL-Report 2000-02 #12;TESLA FEL

  19. TESLA FEL-Report 1999-03 TESLA FEL-Report 1999-03

    E-Print Network [OSTI]

    TESLA FEL-Report 1999-03 #12;TESLA FEL-Report 1999-03 #12;TESLA FEL-Report 1999-03 #12;TESLA FEL-Report 1999-03 #12;TESLA FEL-Report 1999-03 #12;TESLA FEL-Report 1999-03 #12;TESLA FEL-Report 1999-03 #12;TESLA FEL-Report 1999-03 #12;TESLA FEL-Report 1999-03 #12;TESLA FEL-Report 1999-03 #12;TESLA FEL

  20. TESLA FEL-Report 1995-02 TESLA FEL-Report 1995-02

    E-Print Network [OSTI]

    TESLA FEL-Report 1995-02 #12;TESLA FEL-Report 1995-02 #12;TESLA FEL-Report 1995-02 #12;TESLA FEL-Report 1995-02 #12;TESLA FEL-Report 1995-02 #12;TESLA FEL-Report 1995-02 #12;TESLA FEL-Report 1995-02 #12;TESLA FEL-Report 1995-02 #12;TESLA FEL-Report 1995-02 #12;TESLA FEL-Report 1995-02 #12;TESLA FEL

  1. TESLA FEL Report 1996-07 TESLA FEL Report 1996-07

    E-Print Network [OSTI]

    TESLA FEL Report 1996-07 #12;TESLA FEL Report 1996-07 #12;TESLA FEL Report 1996-07 #12;TESLA FEL Report 1996-07 #12;TESLA FEL Report 1996-07 #12;TESLA FEL Report 1996-07 #12;TESLA FEL Report 1996-07 #12;TESLA FEL Report 1996-07 #12;TESLA FEL Report 1996-07 #12;TESLA FEL Report 1996-07 #12;TESLA FEL Report

  2. TESLA FEL Report 1996-06 TESLA FEL Report 1996-06

    E-Print Network [OSTI]

    TESLA FEL Report 1996-06 #12;TESLA FEL Report 1996-06 #12;TESLA FEL Report 1996-06 #12;TESLA FEL Report 1996-06 #12;TESLA FEL Report 1996-06 #12;TESLA FEL Report 1996-06 #12;TESLA FEL Report 1996-06 #12;TESLA FEL Report 1996-06 #12;TESLA FEL Report 1996-06 #12;TESLA FEL Report 1996-06 #12;TESLA FEL Report

  3. TESLA FEL-Report 1995-04 TESLA FEL-Report 1995-04

    E-Print Network [OSTI]

    #12;TESLA FEL-Report 1995-04 #12;TESLA FEL-Report 1995-04 #12;TESLA FEL-Report 1995-04 #12;TESLA FEL-Report 1995-04 #12;TESLA FEL-Report 1995-04 #12;TESLA FEL-Report 1995-04 #12;TESLA FEL-Report 1995-04 #12;TESLA FEL-Report 1995-04 #12;TESLA FEL-Report 1995-04 #12;TESLA FEL-Report 1995-04 #12;TESLA FEL

  4. TESLA FEL-Report 1996-16 TESLA FEL-Report 1996-16

    E-Print Network [OSTI]

    #12;TESLA FEL-Report 1996-16 #12;TESLA FEL-Report 1996-16 #12;TESLA FEL-Report 1996-16 #12;TESLA FEL-Report 1996-16 #12;TESLA FEL-Report 1996-16 #12;TESLA FEL-Report 1996-16 #12;TESLA FEL-Report 1996-16 #12;TESLA FEL-Report 1996-16 #12;TESLA FEL-Report 1996-16 #12;TESLA FEL-Report 1996-16 #12;TESLA FEL

  5. TESLA FEL-Report 1997-02 TESLA FEL-Report 1997-02

    E-Print Network [OSTI]

    TESLA FEL-Report 1997-02 #12;TESLA FEL-Report 1997-02 #12;TESLA FEL-Report 1997-02 #12;TESLA FEL-Report 1997-02 #12;TESLA FEL-Report 1997-02 #12;TESLA FEL-Report 1997-02 #12;TESLA FEL-Report 1997-02 #12;TESLA FEL-Report 1997-02 #12;TESLA FEL-Report 1997-02 #12;TESLA FEL-Report 1997-02 #12;TESLA FEL

  6. Proposed uv-FEL user facility at BNL

    SciTech Connect (OSTI)

    Ben-Zvi, I.; Di Mauro, L.F.; Krinsky, S.; White, M.G.; Yu, L.H.; Batchelor, K.; Friedman, A.; Fisher, A.S.; Halama, H.; Ingold, G.; Johnson, E.D.; Kramer, S.; Rogers, J.T.; Solomon, L.; Wachtel, J.; Zhang, X.

    1991-01-01T23:59:59.000Z

    The NSLS at Brookhaven National Laboratory is proposing the construction of a UV-FEL operating in the wavelength range from visible to 750{Angstrom}. Nano-Coulomb electron pulses will be generated at a laser photo-cathode RF gun at a repetition rate of 10 KHz. The 6 ps pulses will be accelerated to 250 MeV in a superconducting linac. The FEL output will serve four stations with independent wavelength tuning, using two wigglers and two rotating mirror beam switches. Seed radiation for the FEL amplifiers will be provided by conventional tunable lasers, and the final frequency multiplication from the visible or near UV to the VUV will be carried out in the FEL itself. Each FEL will comprise of an initial wiggler resonant to the seed wavelength, a dispersion section, and a second wiggler resonant to the output wavelength. The facility will provide pump probe capability, FEL or FEL, and FEL on synchrotron light from an insersion device on the NSLS X-Ray ring. 15 refs., 2 figs., 3 tabs.

  7. 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.

  8. A Low-Charge, Hard X-Ray FEL Driven with an X-band Injector and Accelerator

    SciTech Connect (OSTI)

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

    2012-02-17T23:59:59.000Z

    After the successful operation of FLASH (Free-Electron Laser in Hamburg) and LCLS (Linac Coherent Light Source), 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 photo-cathode 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 macro-particle 3-D simulation employing several computer codes is presented in this paper, where space charge, wakefields, incoherent and coherent synchrotron radiation (ISR and CSR) 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.

  9. FERMI@Elettra FEL Design Technical Optimization Final Report

    E-Print Network [OSTI]

    Fawley, William; Penn, Gregory; Allaria, Enrico; De Ninno, Giovanni; Graves, William

    2006-01-01T23:59:59.000Z

    LBNL-61333 FERMI@Elettra FEL Design Technical Optimization1 Basic FEL Output5 Important Phenomena which affect the FEL

  10. TESLA FEL-Report 1999-04 TESLA FEL-Report 1999-07

    E-Print Network [OSTI]

    TESLA FEL-Report 1999-04 TESLA FEL-Report 1999-07 #12;TESLA FEL-Report 1999-04 TESLA FEL-Report 1999-07 #12;TESLA FEL-Report 1999-04 TESLA FEL-Report 1999-07 #12;TESLA FEL-Report 1999-04 TESLA FEL-Report 1999-07 #12;TESLA FEL-Report 1999-04 TESLA FEL-Report 1999-07 #12;TESLA FEL-Report 1999-04 TESLA FEL

  11. FEL Design Studies at LBNL: Activities and Plans

    E-Print Network [OSTI]

    Corlett, John N.

    2009-01-01T23:59:59.000Z

    FEL Design Studies at LBNL: Activities and Plans* J.FELs, and participate in two FEL construction projects. Ourand performance limitations of FEL facilities. An internally

  12. TESLA-FEL 2006-04 Far-Infrared Transition and Diffraction Radiation

    E-Print Network [OSTI]

    TESLA-FEL 2006-04 Far-Infrared Transition and Diffraction Radiation Part II: The THz Beamline at the VUV-FEL Linac Sara Casalbuoni1 , Bernhard Schmidt1 , Peter Schm¨user1,2 , Bernd Steffen1,2 1 Deutsches-Electron Laser (VUV-FEL) at DESY has recently been up- graded to a maximum electron energy of 700 MeV, allowing

  13. 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

  14. "Jitter measurement by electro-optical sampling" VUV-FEL at DESY

    E-Print Network [OSTI]

    "Jitter measurement by electro-optical sampling" VUV-FEL at DESY - Armin Azima S. Duesterer, J-resolved. PumpPump--probeprobe experimentexperiment Jitter ! #12;Problem · Jitter of arrival time of VUV arrival time between opt. laser pulse and FEL pulse and "sort" data points afterwards to correct jitter

  15. SASE FEL at the TESLA Facility, Phase 2 The TESLA Test Facility FEL team

    E-Print Network [OSTI]

    SASE FEL at the TESLA Facility, Phase 2 The TESLA Test Facility FEL team June 2002, TESLA-FEL 2002-01 #12;SASE FEL at the TESLA Facility, Phase 2 Abstract The last description of the TESLA Test Facility FEL has been written in 1995 (TESLA- FEL report 95-03). Since then, many changes have developed

  16. TESLA FEL 2004-06 Expected properties of the radiation from VUV-FEL at DESY

    E-Print Network [OSTI]

    TESLA FEL 2004-06 July 2004 Expected properties of the radiation from VUV-FEL at DESY (femtosecond pulse" (200 fs) mode of FEL operation at VUV- FEL, based on a linearized bunch compression that pro- duces FEL radiation. Such a mode of operation was successfully tested at VUV-FEL, Phase I

  17. VISA IB: ULTRA-HIGH BANDWIDTH, HIGH GAIN SASE FEL G. Andonian, A. Murokh, R. Agustsson, C. Pellegrini, S. Reiche, J. B. Rosenzweig, and G. Travish

    E-Print Network [OSTI]

    Brookhaven National Laboratory

    VISA IB: ULTRA-HIGH BANDWIDTH, HIGH GAIN SASE FEL G. Andonian, A. Murokh, R. Agustsson, C spread SASE FEL experiment, the intermediary experiment linking the VISA I and VISA II projects. A highly-election lasers (SASE FEL) promises to be an invalu- able tool for the scientific community. There are current

  18. Stability and Performance of CDRL-FEL

    E-Print Network [OSTI]

    Kim, K.-J.

    2010-01-01T23:59:59.000Z

    the EBTL bandwidth is that the FEL saturation takes place atCaptious Figure 1. The FEL spectrum for different cavitypower POP! generated by the FEL interaction is called the

  19. Staged energy cascades for the LUX FEL

    E-Print Network [OSTI]

    Penn, G.

    2004-01-01T23:59:59.000Z

    a fully 3D time-dependent FEL simulation code, Nucl. Instr.simulations and general FEL physics. This work was supportedan XUV/soft X-ray harmonic-cascade FEL for the proposed LBNL

  20. HIGH-POWER, HIGH-EFFICIENCY FELS

    E-Print Network [OSTI]

    Sessler, A.M.

    2008-01-01T23:59:59.000Z

    M. Kumada, "Scaling of the FEL-ID Equations", ELF Note 128,Instability in a High-power, Short- Wavelength FEL", Proc.of the Ninth FEL" Conference, Williamsburg (1988), and

  1. FEL Design Studies at LBNL: Activities and Plans

    SciTech Connect (OSTI)

    Corlett, John N.; Fawley, W.; Lidia, S.; Padmore, H.; Penn, G.; Pogorelov, I.; Qiang, J.; Sannibale, F.; Staples, J.; Steier, C.; Venturini, M.; Wan, W.; Wilcox, R.; Zholents, A.

    2007-03-01T23:59:59.000Z

    LBNL staff are currently pursuing R&D for future x-ray FELs, and participate in two FEL construction projects. Our strategy is to address the most fundamental challenges, which are the cost-drivers and performance limitations of FEL facilities. An internally funded R&D program is aimed at investigating accelerator physics and technologies in three key areas: (1) Theoretical study, modeling, and experimental development of low emittance, high quantum efficiency cathodes; (2) Design studies of electron beam delivery systems, including emittance manipulations, high-resolution modeling of 6-D phase space, and low-emittance beam transport; and (3) Design studies of optical manipulations of electron beams for seeded and SASE FELs, providing short x-ray pulses of variable duration, synchronous with the seed and pump laser sources, and also long transform-limited pulses with a narrow bandwidth. Design studies of means for production of attosecond x-ray pulses at various wavelengths. We are collaborators in the FERMI{at}Elettra seeded FEL facility under construction at Sincrotrone Trieste, Italy, participating in accelerator design and FEL physics studies, and mechanical and electrical engineering. We are participating in the LCLS project at SLAC, implementing our design of stabilized timing and synchronization systems. Here we outline our long-term objectives, and current activities.

  2. 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...

  3. Jefferson Lab News - JLab FEL Wins R&D 100 Award | Jefferson...

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

    award. The 2005 award goes to: The Tunable Energy Recovered High Power Infrared Free-Electron Laser, lead by a team of nine Jefferson Lab scientists and engineers. The...

  4. 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 (

  5. Recent results from FLASH (VUV FEL at DESY)

    E-Print Network [OSTI]

    14.01.2005 26.04.2006 32 nm 13 nm current value average maximum #12;Production of ultra-short radiation pulses in the VUV FEL An ultra-short current spike (50-100 fs FWHM) with peak current 1-2 k in the undulator (mainly dark current) Dispersion, dogleg Laser/RF phase stability: jitters and slow drifts

  6. 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

  7. 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.

  8. TTF/VUV-FEL meeting, 21. Mar 06 SaseFelPhotonDiagnostics

    E-Print Network [OSTI]

    TTF/VUV-FEL meeting, 21. Mar 06 SaseFelPhotonDiagnostics Gas Monitor Detector Electronics from charged particles to digital value Fini Jastrow, TTF/VUV-FEL meeting, 21. Mar 06 #12;TTF/VUV-FEL meeting, 21. Mar 06 SaseFelPhotonDiagnostics The Detector Ion Current Measurement Electron Pulse Measurement

  9. Machine Parameter Studies for an FEL Facility Using Staff

    E-Print Network [OSTI]

    Reinsch, M.

    2014-01-01T23:59:59.000Z

    PARAMETER STUDIES FOR AN FEL FACILITY USING STAFF ? M.USA Abstract Designing an FEL facility requires balancingmultiple science needs, FEL and accelerator physics

  10. A STEADY-STATE FEL: PARTICLE DYNAMICS IN THE FEL PORTION OF A TWO-BEAM ACCELERATOR

    E-Print Network [OSTI]

    Sternbach, E.

    2008-01-01T23:59:59.000Z

    September 8-13, 1985 A STEADY-STATE FEL: PARTICLE DYNAMICSIN THE FEL PORTION OF A TWO-BEAM ACCELERATOR E. SternbachLBL-19939 A STEADY-STATE FEL: PARTICLE DYNAMICS IN THE FEL

  11. 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.

  12. 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:...

  13. Optimization for Single-Spike X-Ray FELs at LCLS with a Low Charge Beam

    SciTech Connect (OSTI)

    Wang, L.; Ding, Y.; Huang, Z.; /SLAC

    2011-12-14T23:59:59.000Z

    The Linac Coherent Light Source is an x-ray free-electron laser at the SLAC National Accelerator Laboratory, which is operating at x-ray wavelengths of 20-1.2 Angstrom with peak brightness nearly ten orders of magnitude beyond conventional synchrotron radiation sources. At the low charge operation mode (20 pC), the x-ray pulse length can be <10 fs. In this paper we report our numerical optimization and simulations to produce even shorter x-ray pulses by optimizing the machine and undulator setup at 20 pC charge. In the soft x-ray regime, with combination of slotted-foil or undulator taper, a single spike x-ray pulse is achievable with peak FEL power of a few 10s GW. Linac Coherent Light Source (LCLS), the world's first hard x-ray Free electron laser (FEL), has started operation since 2009. With nominal operation charge of 250 pC, the generated x-ray pulse length is from 70 fs to a few hundred fs. This marks the beginning of a new era of ultrashort x-ray sciences. In addition, a low charge (20pC) operation mode has also been established. Since the collective effects are reduced at the low charge mode, we can increase the compression factor and still achieve a few kA peak current. The expected electron beam and x-ray pulses are less than 10 fs. There are growing interests in even shorter x-ray pulses, such as fs to sub-fs regime. One of the simple solutions is going to even lower charge. As discussed, single-spike x-ray pulses can be generated using 1 pC charge. However, this charge level is out of the present LCLS diagnostic range. 20 pC is a reasonable operation charge at LCLS, based on the present diagnostic system. At 20 pC in the soft x-ray wavelength regime, we have experimentally demonstrated that FEL can work at undercompression or over-compression mode, such as 1 degree off the full-compression; at full-compression, however, there is almost no lasing. In hard x-ray wavelength regime, we observed that there are reasonable photons generated even at full-compression mode, although the photon number is less than that from under-compression or over-compression mode. Since we cannot measure the x-ray pulse length at this time scale, the machine is typically optimized for generating maximum photons, not minimum pulse length. In this paper, we study the methods of producing femtosecond (or single-spike) x-ray pulses at LCLS with 20 pC charge, based on start-to-end simulations. Figure 1 shows a layout of LCLS. The compression in the second bunch compressor (BC2) determines the final e-beam bunch length. However, the laser heater, dog-leg after the main linac (DL2) and collective effects also affect the final bunch length. To adjust BC2 compression, we can either change the L2 phase or BC2 R{sub 56}. In this paper we only tune L2 phase while keep BC2 R{sub 56} fixed. For the start-to-end simulations, we used IMPACT-T and ELEGANT tracking from the photocathode to the entrance of the undulator, after that the FEL radiation was simulated with GENESIS. IMPACT-T tracks about 10{sup 6} particles in the injector part until 135 MeV, including 3D space charge force. The output particles from IMPACT-T are smoothed and increased to 12 x 10{sup 6} to reduce high-frequency numerical noise for subsequent ELEGANT simulations, which include linear and nonlinear transport effects, a 1D transient model of CSR, and longitudinal space charge effects, as well as geometric and resistive wake fields in the accelerator. In GENESIS part, the longitudinal wake field from undulator chamber and longitudinal space field are also included.

  14. Harmonic cascade FEL designs for LUX

    E-Print Network [OSTI]

    2004-01-01T23:59:59.000Z

    1.3: a fully 3D time-dependent FEL sim- ulation code, Nucl.a XUV/soft X-ray harmonic-cascade FEL for the proposed LBNLLBNL-56329 Harmonic cascade FEL designs for LUX G. Penn, M.

  15. Optimization Studies of the FERMI at ELETTRA FEL Design

    SciTech Connect (OSTI)

    De Ninno, Giovanni; Fawley, William M.; Penn, Gregory E.; Graves,William

    2005-08-25T23:59:59.000Z

    The FERMI at ELETTRA project at Sincotrone Trieste involves two FEL's, each based upon the principle of seeded harmonic generation and using the existing ELETTRA injection linac at 1.2 GeV beam energy. Scheduled to be completed in 2008, FEL-1 will operate in 40-100 nm wavelength range and will involve one stage of harmonic up-conversion. The second undulator line, FEL-2, will begin operation two years later in the 10-40 nm wavelength range and use two harmonic stages operating as a cascade. The FEL design assumes continuous wavelength tunability over the full wavelength range, and polarization tunability of the output radiation including vertical or horizontal linear as well as helical polarization. The design considers focusing properties and segmentation of realizable undulators and available input seed lasers. We review the studies that have led to our current design. We present results of simulations using GENESIS and GINGER simulation codes including studies of various shot-to-shot fluctuations and undulator errors. Findings for the expected output radiation in terms of the power, transverse and longitudinal coherence are reported.

  16. HARMONIC CASCADE FEL DESIGNS FOR LUX G. Penn, M. Reinsch, J. Wurtele

    E-Print Network [OSTI]

    Wurtele, Jonathan

    HARMONIC CASCADE FEL DESIGNS FOR LUX G. Penn, M. Reinsch, J. Wurtele , J.N. Corlett, W.M. Fawley, A stages of higher harmonic generation, seeded by a 200­250 nm laser of similar duration. This laser mod then produces ra- diation at a higher harmonic after entering a second, differ- ently tuned undulator. Repeated

  17. 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

  18. 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

  19. Optimization of a high efficiency FEL amplifier

    E-Print Network [OSTI]

    Schneidmiller, E A

    2014-01-01T23:59:59.000Z

    The problem of an efficiency increase of an FEL amplifier is now of great practical importance. Technique of undulator tapering in the post-saturation regime is used at the existing x-ray FELs LCLS and SACLA, and is planned for use at the European XFEL, Swiss FEL, and PAL XFEL. There are also discussions on the future of high peak and average power FELs for scientific and industrial applications. In this paper we perform detailed analysis of the tapering strategies for high power seeded FEL amplifiers. Application of similarity techniques allows us to derive universal law of the undulator tapering.

  20. Interactive Video Cubism Sidney Fels

    E-Print Network [OSTI]

    Fels, Sidney S.

    Interactive Video Cubism Sidney Fels Dept. of Electrical and Computer Engineering University@mic.atr.co.jp ABSTRACT This paper presents an interactive video visualization system. In this visualization video data is considered to be a block of three dimensional data where frames of video data comprise the third dimension

  1. Katja Honkavaara, TTF/VUV-FEL meeting, 21.02.2006 TTF/VUV-FEL meeting 21.02.2006

    E-Print Network [OSTI]

    Katja Honkavaara, TTF/VUV-FEL meeting, 21.02.2006 TTF/VUV-FEL meeting 21.02.2006 Overview + QE measurements #12;Katja Honkavaara, TTF/VUV-FEL meeting, 21.02.2006 Accelerator studies in KW 9-14 · Priority on ILC and XFEL related studies (not VUV-FEL) ­ VUV-FEL benefits directly or indirectly from most

  2. aps sase fel: Topics by E-print Network

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

    14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 SASE FEL at the TESLA Facility, Phase 2 The TESLA Test Facility FEL team Physics Websites Summary: SASE FEL...

  3. Towards attosecond X-ray pulses from the FEL

    E-Print Network [OSTI]

    Zholents, Alexander A.; Fawley, William M.

    2004-01-01T23:59:59.000Z

    can be used instead of HC FEL. In the following illustra-UM is now tuned for resonant FEL interaction with the 32-nmAttosecond X-Ray Pulses from the FEL Alexander A. Zholents,

  4. RADIO FREQUENCY PHASE IN THE FEL SECTION OF A TBA

    E-Print Network [OSTI]

    Kuenning, R.W.

    2008-01-01T23:59:59.000Z

    and A. M. Sessler. "A Steady-State FEL: Particle Dynamicsin the FEL Portion of a Two-Beam Accelerator," Proc. of 7thand Amplitude Studies of an FEL: Steady State. lD. Resonant

  5. FEL GAIN LENGTH AND TAPER MEASUREMENTS AT LCLS

    E-Print Network [OSTI]

    Ratner, D.

    2010-01-01T23:59:59.000Z

    more than double the coherent, FEL power over the satura-FEL GAIN LENGTH AND TAPER MEASUREMENTS AT LCLS ? D.Figure 11: Post-saturation FEL pulse energy for a taper with

  6. Start-Up of FEL Oscillator from Shot Noise

    E-Print Network [OSTI]

    Kumar, V.; Krishnagopal, S.; Fawley, W.M.

    2007-01-01T23:59:59.000Z

    of start-up of the CUTE-FEL oscillator from shot noiseof passes required for the FEL to saturate is equivalent toSTART-UP OF FEL OSCILLATOR FROM SHOT NOISE V. Kumar ? , S.

  7. 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.

  8. 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

  9. Beam Dynamics Study of X-Band Linac Driven X-Ray FELS

    SciTech Connect (OSTI)

    Adolphsen, C.; Limborg-Deprey, C.; Raubenheimer, T.O.; Wu, J.; /SLAC; Sun, Y.; /SLAC

    2011-12-13T23:59:59.000Z

    Several linac driven X-ray Free Electron Lasers (XFELs) are being developed to provide high brightness photon beams with very short, tunable wavelengths. In this paper, three XFEL configurations are proposed that achieve LCLS-like performance using X-band linac drivers. These linacs are more versatile, efficient and compact than ones using S-band or C-band rf technology. For each of the designs, the overall accelerator layout and the shaping of the bunch longitudinal phase space are described briefly. During the last 40 years, the photon wavelengths from linac driven FELs have been pushed shorter by increasing the electron beam energy and adopting shorter period undulators. Recently, the wavelengths have reached the X-ray range, with FLASH (Free-Electron Laser in Hamburg) and LCLS (Linac Coherent Light Source) successfully providing users with soft and hard X-rays, respectively. FLASH uses a 1.2 GeV L-band (1.3 GHz) superconducting linac driver and can deliver 10-70 fs FWHM long photon pulses in a wavelength range of 44 nm to 4.1 nm. LCLS uses the last third of the SLAC 3 km S-band (2.856 GHz) normal-conducting linac to produce 3.5 GeV to 15 GeV bunches to generate soft and hard X-rays with good spatial coherence at wavelengths from 2.2 nm to 0.12 nm. Newer XFELs (at Spring8 and PSI) use C-band (5.7 GHz) normal-conducting linac drivers, which can sustain higher acceleration gradients, and hence shorten the linac length, and are more efficient at converting rf energy to bunch energy. The X-band (11.4 GHz) rf technology developed for NLC/GLC offers even higher gradients and efficiencies, and the shorter rf wavelength allows more versatility in longitudinal bunch phase space compression and manipulation. In the following sections, three different configurations of X-band linac driven XFELs are described that operate from 6 to 14 GeV. The first (LOW CHARGE DESIGN) has an electron bunch charge of only 10 pC; the second (OPTICS LINEARIZATION DESIGN) is based on optics linearization of the longitudinal phase space in the first stage bunch compressor and can operate with either a high (250 pC) or low (20 pC) bunch charge; and the third (LCLS INJECTOR DESIGN) is similar to LCLS but uses an X-band linac after the first stage bunch compressor at 250 MeV to achieve a final beam energy up to 14 GeV. Compared with LCLS, these X-band linacs are at least a factor of three shorter.

  10. Development of a new generation of optical slope measuring profiler

    E-Print Network [OSTI]

    Yashchuk, Valeriy V.

    2010-01-01T23:59:59.000Z

    Free Electron Laser (FEL), LCLS, National Synchrotron Light1-3]. The beamlines for LCLS, NSLS-II, and planned upgrade

  11. Nuclear Physics: Recent Talks

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

    Free Electron Laser (FEL) Medical Imaging Physics Topics Campaigns Meetings Recent Talks Archived Talks Additional Information Computing at JLab Operations Logbook Physics Topics:...

  12. Nuclear Physics: Campaigns

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

    Free-Electron Laser (FEL) Medical Imaging Physics Topics Campaigns The Structure of the Nuclear Building Blocks The Structure of Nuclei Symmetry Tests in Nuclear Physics Meetings...

  13. Nuclear Physics: Experiment Research

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

    UserResearcher Information print version Research Highlights Public Interest Nuclear Physics Accelerator Free Electron Laser (FEL) Medical Imaging Physics Topics Campaigns...

  14. Nuclear Physics: Archived Talks - Accelerator

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

    Free Electron Laser (FEL) Medical Imaging Physics Topics Campaigns Meetings Recent Talks Archived Talks Accelerator Hall A Hall B Hall C 12 GeV Upgrade Experimental Techniques...

  15. HIGH-REP RATE PHOTOCATHODE INJECTOR FOR LCLS

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

    pulse shaping techniques will be presented. 1 INTRODUCTION To develop X-ray Free electron laser (FEL) as one of the possible candidates for future fourth generation light...

  16. Microsoft Word - Pac99_pcgun_final1.doc

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

    At the Advanced Photon Source (APS) at Argonne National Laboratory (ANL), a free-electron laser (FEL) based on the self-amplified spontaneous emission (SASE) process is...

  17. Experiment generates THz radiation 20,000 times brighter than...

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

    way for application development An experiment conducted with Jefferson Lab's Free-Electron Laser (FEL) has shown how to make a highly useful form of light - called terahertz...

  18. 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

  19. Excitements and Challenges for Future Light Sources Based on X-Ray FELs

    E-Print Network [OSTI]

    -ray Laser Laboratory #12;LLINACINAC CCOHERENTOHERENT LLIGHTIGHT SSOURCEOURCE 2 Km 0 Km 3 Km #12;LCLS brightness of the LCLS and other facilities operating or under construction LEUTL TTF FEL LCLS Spontaneous)(B. Faatz) UCLAUCLA #12;LCLS - The First Experiments Team Leaders: AbsorptionResonanceRaman t0 t1 t2 t3 t4 t

  20. TURKISH ACCELERATOR COMPLEX & STATUS OF TAC SASE FEL

    E-Print Network [OSTI]

    TURKISH ACCELERATOR COMPLEX & STATUS OF TAC SASE FEL Dr. Hatice DURAN YILDIZ On the Behalf of the TAC & TAC SASE-FEL Group DESY April 5, 2011 #12;2 Content Aim & Phases of the TAC Project TAC-TARLA Facility TARLA Resonator System TAC SASE-FEL Group Members & Duties TAC SASE-FEL Tentative Parameters

  1. Beam Line Commissioning of a UV/VUV FEL at Jefferson Lab

    SciTech Connect (OSTI)

    Benson, Stephen; Blackburn, Keith; Bullard, Daniel; Clavero Perez, Cesar; Coleman, James; Dickover, Cody; Douglas, David; Ellingsworth, Forrest; Evtushenko, Pavel; Hernandez-Garcia, Carlos; Gould, Christopher; Gubeli, Joseph; Hardy, David; Jordan, Kevin; Klopf, John; James, Kortze; Legg, Robert; Marchlik, Matthew; Moore, Steven; Neil, George; Powers, Thomas; Sexton, Daniel; Shinn, Michelle D; Tennant, Christopher; Walker, Richard; Williams, Gwyn; Wilson, Frederick

    2011-08-01T23:59:59.000Z

    Many novel applications in photon sciences require very high brightness and/or short pulses in the vacuum ultra-violet (VUV). Jefferson Lab has commissioned a UV oscillator with high gain and has transported the third harmonic of the UV to a user lab. The experimental performance of the UV FEL is much better than simulated performance in both gain and efficiency. This success is important for efforts to push towards higher gain FELs at short wavelengths where mirrors absorb strongly. We will report on efforts to characterize the UV laser and the VUV coherent harmonics as well as designs to lase directly in the VUV wavelength range.

  2. Microsoft Word - ls280.doc

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

    Advanced Photon Source (APS). This line will initially be used to demonstrate a free-electron laser (FEL) based on the self-amplified spontaneous-emission (SASE) process. The FEL...

  3. BNL | ATF Publications

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

    on Plasma Science, Volume 33, Issue 1, (2004) FEL 2004: The 26th International Free-Electron Laser Conference and the 11th FEL User-Workshop, August 29 - September 3, 2004,...

  4. Production of Ultrashort FEL XUV Pulses via a Reverse Undulator Taper

    E-Print Network [OSTI]

    Fawley, William M.

    2007-01-01T23:59:59.000Z

    Production of Ultrashort FEL XUV Pulses via a Reverseof 2009. In recent years, FEL researchers have explored ara- diator undulators, the FEL emission will predomi- nately

  5. EXPERIENCE AND PLANS OF THE JLAB FEL FACILITY AS A USER FACILITY

    SciTech Connect (OSTI)

    Michelle D. Shinn

    2007-08-26T23:59:59.000Z

    Jefferson Lab's IR Upgrade FEL building was planned from the beginning to be a user facility, and includes an associated 600 m2 area containing seven laboratories. The high average power capability (multikilowatt-level) in the near-infrared (1-3 microns), and many hundreds of watts at longer wavelengths, along with an ultrafast (~ 1 ps) high PRF (10's MHz) temporal structure makes this laser a unique source for both applied and basic research. In addition to the FEL, we have a dedicated laboratory capable of delivering high power (many tens of watts) of broadband THz light. After commissioning the IR Upgrade, we once again began delivering beam to users in 2005. In this presentation, I will give an overview of the FEL facility and its current performance, lessons learned over the last two years, and a synopsis of current and future experiments.

  6. FEL

    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) Environmental Assessments (EA) /EmailMolecularGE,Ozone Layer F.t aFAQs

  7. 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

  8. Parameter Selection and Longitudinal Phase Space Simulation for a Single Stage X-Band FEL Driver at 250 MeV

    SciTech Connect (OSTI)

    Sun, Yipeng; Raubenheimer, Tor; Wu, Juhao; /SLAC; ,

    2011-08-19T23:59:59.000Z

    Hard x-ray Free electron lasers (FEL) are being built or proposed at many accelerator laboratories as it supports wide range of applications in many aspects. Most of the hard x-ray FEL design is similar with the SLAC Linac Coherent Light Source (LCLS), which features a two (or multiple) stage bunch compression. For the first stage of the bunch compression, usually the beam is accelerated in a lower-frequency RF section (such as S-band for LCLS), and then the longitudinal phase space is linearized by a higher-frequency RF section (harmonic RF, such as X-band for LCLS). In this paper, a compact hard x-ray FEL design is proposed, which is based on X-band RF acceleration and eliminating the need of a harmonic RF. The parameter selection and relation is discussed, and the longitudinal phase space simulation is presented. The FEL coherence condition of the electron beam in the undulators requires a large charge density, a small emittance and small energy spread. The RMS electron bunch length from the injector is in the ps scale, with a bunch charge in the range of hundreds pC to several nC, which means that the current is roughly 0.1 kA. According to the requirement from soft x-ray lasing and hard x-ray lasing, a peak current of 1 kA and 3 kA is needed respectively. Thus the bunch has to be compressed. Usually a two stage bunch compression or multipole stage bunch compression is adopted. The z-correlated energy chirp is normally established by letting the beam pass through a section of RF cavities, with a RF phase off crest. As stated above, S-band RF (3 GHz) acceleration could be applied in this section. Due to the nature of RF acceleration wave, the chirp on the bunch is not linear, but has the RF curvature on it. In order to linearize the energy chirp, a harmonic RF section with higher frequency is needed. For LCLS a short X-band RF section (12 GHz) is used which is a fourth order harmonic. The linearized bunch is then passing by a dispersive region, in which the particles with different energy have different path length. A four dipole chicane is the natural choice for the dispersive region. As the example illustrated in Figure 1, the head of the bunch has smaller energy, and gets a stronger bending kick from the dipole magnet, then has a longer path length in the dispersive region. Similarly, the tail of the bunch has larger energy and shorter path length in the dispersive region. At the exit of the dispersive region, the relative longitudinal position of the head and tail of the bunch both move to the center of the bunch, so the bunch length will be shorter.

  9. 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

  10. 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

  11. Comment to the paper: 'Seeded quantum FEL at 478 keV' AIP Conf. Proc. 'Light at Extreme Intensities' 1462 173-176 (2012)'

    E-Print Network [OSTI]

    Vittoria Petrillo

    2012-12-19T23:59:59.000Z

    We criticize the thesis exposed the paper 'Seeded quantum FEL at 478 keV' AIP Conf. Proc. 'Light at Extreme Intensities,' 1462 173-176 (2012), which presents the possibility of producing gamma rays at 478 KeV by means of a seeded quantum FEL driven by an electron beam at 125 MeV, current I=40 A, interacting with an infrared laser. We show that, in the case analyzed, the FEL Pierce parameter has a value two orders of magnitude less than what claimed in the paper in question, overturning the conclusions of the analysis.

  12. 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 (

  13. average power fel: Topics by E-print Network

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

    coverage (fundamental) 3 (5)1 (8) FEL undulators 2012 (?)2009 (2013)Operation start TESLA (upgrade) LCLS (upgrade) X-ray FEL Projects in Preconstruction 12;Status of X-ray...

  14. FEL Design Studies at LBNL: Activities and Plans

    E-Print Network [OSTI]

    Corlett, John N.

    2009-01-01T23:59:59.000Z

    FEL Design Studies at LBNL: Activities and Plans* J.CA 94720, USA Introduction LBNL staff are currently pursuingRate FEL Facility The LBNL program in R&D toward advanced

  15. Investigation of a 2-Colour Undulator FEL Using Puffin

    E-Print Network [OSTI]

    Campbell, L T; Reiche, S

    2013-01-01T23:59:59.000Z

    Initial studies of a 2-colour FEL amplifier using one monoenergetic electron beam are presented. The interaction is modelled using the unaveraged, broadband FEL code Puffin. A series of undulator modules are tuned to generate two resonant frequencies along the FEL interaction and a self-consistent 2-colour FEL interaction at widely spaced non-harmonic wavelengths at 1nm and 2.4nm is demonstrated.

  16. FEL3330 Networked and Multi-Agent Control Spring 2011

    E-Print Network [OSTI]

    Dimarogonas, Dimos

    FEL3330 Networked and Multi-Agent Control Systems Spring 2011 Automatic Control School of Electrical Engineering Royal Institute of Technology Lecture 1 1 March 29, 2011 #12;FEL3330 Networked Lecture 1 3 March 29, 2011 #12;FEL3330 Networked and Multi-Agent Control Systems Lecture 1: Introduction

  17. ETHERNET BASED EMBEDDED IOC FOR FEL CONTROL SYSTEM

    SciTech Connect (OSTI)

    Jianxun Yan; Daniel Sexton; Albert Grippo; Steven Moore; Kevin Jordan

    2008-01-23T23:59:59.000Z

    An Ethernet based embedded Input Output Controller (IOC) has been developed to upgrade the control system for the Free Electron Laser Project at Jefferson Lab. The embedded IOC, called the Single Board IOC (SBIOC), was integrated with a ColdFire embedded microprocessor and a Field Programmable Gate Array (FPGA) on a circuit board, which can be easily configured to control different kinds of I/O devices. The SBIOC provided features of a complete System-on-Module (SOM) as a stand alone system with abundant high speed I/O ports to couple with suitable devices. The software kits, Experimental Physics and Industrial Control System (EPICS) and Real Time Executive for Multiprocessor System (RTEMS), were chosen to work with our existing control system. The embedded IOC system has the features of a low cost IOC, free open source RTOS, plug-and-play-like ease of installation and flexibility.

  18. 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.

  19. 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

  20. 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

  1. COMMISSIONING OF THE VUV-FEL INJECTOR AT TTF S. Schreiber

    E-Print Network [OSTI]

    COMMISSIONING OF THE VUV-FEL INJECTOR AT TTF S. Schreiber , DESY, Hamburg, Germany for the VUV-FEL group Abstract The VUV-FEL at the TESLA Test Facility (TTF) at DESY is being upgraded to an FEL user project of the TESLA collaboration at present is the VUV-FEL at the TESLA Test Facility (TTF) at DESY[1

  2. Connecting Lab-Based Attosecond Science with FEL research

    ScienceCinema (OSTI)

    None

    2011-10-06T23:59:59.000Z

    In the last few years laboratory-scale femtosecond laser-based research using XUV light has developed dramatically following the successful development of attosecond laser pulses by means of high-harmonic generation. Using attosecond laser pulses, studies of electron dynamics on the natural timescale that electronic processes occur in atoms, molecules and solids can be contemplated, providing unprecedented insight into the fundamental role that electrons play in photo-induced processes. In my talk I will briefly review the present status of the attosecond science research field in terms of present and foreseen capabilities, and discuss a few recent applications, including a first example of the use of attosecond laser pulses in molecular science. In addition, I will discuss very recent results of experiments where photoionization of dynamically aligned molecules is investigated using a high-harmonics XUV source. Photoionization of aligned molecules becomes all the more interesting if the experiment is performed using x-ray photons. Following the absorption of x-rays, ejected photoelectrons can be used as a probe of the (time-evolving) molecular structure, making use of intra-molecular electron diffraction. This amounts, as some have stated, to ?illuminating the molecule from within?. I will present the present status of our experiments on this topic making use of the FLASH free electron laser in Hamburg. Future progress in this research field not only depends on the availability of better and more powerful light sources, but also requires sophisticated detector strategies. In my talk I will explain how we are trying to meet some of the experimental challenges by using the Medipix family of detectors, which we have already used for time- and space-resolved imaging of electrons and ions.

  3. 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.

  4. 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

  5. GINGER simulations of short-pulse effects in the LEUTL FEL

    E-Print Network [OSTI]

    Huang, Z.; Fawley, W.M.

    2001-01-01T23:59:59.000Z

    with Þ in a high-gain FEL. GINGER does not presently modelcontribution in the LEUTL FEL. However, for a true GaussianSHORT-PULSE EFFECTS IN THE LEUTL FEL £ Z. Huang Ý , Advanced

  6. A Study of Phase Control in the FEL Two-Beam Accelerator

    E-Print Network [OSTI]

    Sessler, Andrew M.

    2008-01-01T23:59:59.000Z

    Study of Phase Control in the FEL Two-Beam Accelerator A.M.OF PHASE CONTROL IN THE FEL TWO-BEAM ACCELERATOR* ANDREW M.OF PHASE CONTROL IN THE FEL TWO-BEAM ACCELERATOR Andrew M.

  7. Oscillator Seeding of a High Gain Harmonic Generation FEL in a Radiator-First Configuration

    E-Print Network [OSTI]

    Gandhi, P.

    2014-01-01T23:59:59.000Z

    Proceedings of the 2010 FEL Conference, Malm¨o, Sweden,Proceedings of the 2010 FEL Conference, Malm¨o, Sweden,of a high gain harmonic generation FEL in a radiator-first

  8. Performance of Hole-Coupling Resonator in the Presence of Asymmetric Modes and FEL Gain

    E-Print Network [OSTI]

    Xie, M.

    2011-01-01T23:59:59.000Z

    is derived in, K. -1. Kim, "FEL Gain Taking into Accountof Asymmetric Modes :1nd FEL Gain M. Xie and K. -J. KimOF ASYMMETRIC MODES AND FEL GAIN· Ming Xie and Kwang-Je Kim

  9. Technical Design and Optimization Study for the FERMI@Elettra FEL Photoinjector

    E-Print Network [OSTI]

    Lidia, Steven M.; Penco, Giuseppe; Trovo', Mauro

    2006-01-01T23:59:59.000Z

    Source for the ELETTRA Linac FEL”, ST/M-03/02, May 2003. [for the FERMI @ Elettra FEL”, Proceedings of the 27 thStudy for the FERMI@Elettra FEL Photoinjector Steve Lidia (

  10. Studies of a Linac Driver for a High Repetition Rate X-Ray FEL

    E-Print Network [OSTI]

    Venturini, M.

    2012-01-01T23:59:59.000Z

    REPETITION RATE X-RAY FEL ? M. Venturini † , J. Corlett, L.support a high repetition rate FEL operating in the soft x-of high-repetition rate FEL machine generat- ing soft x-rays

  11. Suppression of Mode-Beating in a Saturated Hole-Coupling FEL Oscillator

    E-Print Network [OSTI]

    Krishnagopal, S.

    2011-01-01T23:59:59.000Z

    cavity case L and with an FEL interaction. of mode-beatingMode profiles (with an FEL interaction) at three differentin a Saturated Hole-coupled FEL Oscillator S. Krishnagopal,

  12. Novel Techniques for Single-Pulse Spectrum and Pulsewidth Measurements for an IR-FEL

    E-Print Network [OSTI]

    Leemans, W.P.

    2011-01-01T23:59:59.000Z

    ofthe LBL/Stanford diagnostics. FEL Thespectral andtemporalMeasurements for an IR-FEL W.P. Leemans, J.A. Edighoffer, K-Measurements for an IR-FEL* W. P. Leemans, J. A. Edighoffer,

  13. Design study of the bending sections between harmonic cascade FEL stages

    E-Print Network [OSTI]

    Wan, Weishi; Corlett, John; Fawley, William; Zholents, A.

    2004-01-01T23:59:59.000Z

    A XUV/Soft X-Ray Harmonic- Cascade FEL for the Proposed LBNLin a Cascaded Harmonic FEL CBP Tech Note-281, Februarybetween Harmonic Cascade FEL Stages W. Wan, J. Corlett, W.

  14. A HIGH REPETITION RATE VUV-SOFT X-RAY FEL CONCEPT

    E-Print Network [OSTI]

    2007-01-01T23:59:59.000Z

    performance, based on a number of FEL configurations, fed byREPETITION RATE VUV-SOFT X-RAY FEL CONCEPT* J. Corlett # ,will be switched into each FEL in the array, in a time-

  15. Some issues and subtleties in numerical simulation of X-ray FEL's

    E-Print Network [OSTI]

    Fawley, William M.

    2002-01-01T23:59:59.000Z

    ed Spontaneous Emission FEL”, submitted to Phys. Rev, 2002;V. Litvinenko, “Macroparticle FEL Model with Self-ConsistentInitial Stage of a SASE FEL”, Poster MO-P-15, these proceed-

  16. Design Studies for a High-Repetition-Rate FEL Facility at LBNL.

    E-Print Network [OSTI]

    CORLETT, J.

    2009-01-01T23:59:59.000Z

    for a High-Repetition-Rate FEL Facility at LBNL* A. Brepetition-rate, seeded FEL. Figure 2: Longitudinal phase-spontaneous emission FEL with energy-chirped electron beam

  17. The Standing Wave FEL/TBA: Realistic Cavity Geometry and Energy Extraction

    E-Print Network [OSTI]

    Kim, J.S.

    2008-01-01T23:59:59.000Z

    the Proceedings The Standing Wave FEL/TBA: Realistic CavityAC03- 76SF00098 The Standing Wave FEL/TBA: Realistic Cavitythe conventional wiggle-averaged FEL equations[6]. Using the

  18. FULL ELECTROMAGNETIC FEL SIMULATION VIA THE LORENTZ-BOOSTED FRAME TRANSFORMATION

    E-Print Network [OSTI]

    Fawley, William

    2010-01-01T23:59:59.000Z

    FULL ELECTROMAGNETIC FEL SIMULATION VIA THE LORENTZ-BOOSTEDrest frame), the red-shifted FEL radiation and blue-shiftedper- mit direct study of FEL problems for which the eikonal

  19. Three-Dimensional Simulation of a Hole-Coupled FEL Oscillator

    E-Print Network [OSTI]

    Krishnagopal, S.

    2008-01-01T23:59:59.000Z

    resonator in the presence of FEL gain, M.Xie and K. -J.Kim,Simulation of a Hole-Coupled FEL Oscillator S. KrishnagopalSimulation of a Hole-Coupled FEL Oscillator S. Krishnagopal,

  20. Technique for the Generation of Attosecond X-Ray Pulses Using an FEL

    E-Print Network [OSTI]

    Penn, G.; Zholents, A.A.

    2005-01-01T23:59:59.000Z

    experiments at a X-ray SASE FEL”, Optics Communications,considerations for a SASE X-ray FEL”, Nucl. Instr. Methodsa fully 3D time-dependent FEL simulation code”, Nucl. Instr.

  1. FEL Gain Taking into Account Diffraction and Electron Beam Emittance; Generalized Madey's Theorem

    E-Print Network [OSTI]

    Kim, K.-J.

    2011-01-01T23:59:59.000Z

    be published in the Proceedings FEL Gain Taking into AccountLBL--30628 DE92 002262 FEL Gain Taking into Accountfunction SF contains the FEL dynamics, and will be regarded

  2. 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.

  3. 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,

  4. 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

  5. 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.

  6. 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

  7. 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

  8. 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-

  9. 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.

  10. 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

  11. 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.

  12. 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.

  13. 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,

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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

  19. 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.

  20. 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