WorldWideScience

Sample records for upgrade fel optical

  1. HIGH AVERAGE POWER OPTICAL FEL AMPLIFIERS

    International Nuclear Information System (INIS)

    2005-01-01

    Historically, the first demonstration of the optical FEL was in an amplifier configuration at Stanford University [l]. There were other notable instances of amplifying a seed laser, such as the LLNL PALADIN amplifier [2] and the BNL ATF High-Gain Harmonic Generation FEL [3]. However, for the most part FELs are operated as oscillators or self amplified spontaneous emission devices. Yet, in wavelength regimes where a conventional laser seed can be used, the FEL can be used as an amplifier. One promising application is for very high average power generation, for instance FEL's with average power of 100 kW or more. The high electron beam power, high brightness and high efficiency that can be achieved with photoinjectors and superconducting Energy Recovery Linacs (ERL) combine well with the high-gain FEL amplifier to produce unprecedented average power FELs. This combination has a number of advantages. In particular, we show that for a given FEL power, an FEL amplifier can introduce lower energy spread in the beam as compared to a traditional oscillator. This properly gives the ERL based FEL amplifier a great wall-plug to optical power efficiency advantage. The optics for an amplifier is simple and compact. In addition to the general features of the high average power FEL amplifier, we will look at a 100 kW class FEL amplifier is being designed to operate on the 0.5 ampere Energy Recovery Linac which is under construction at Brookhaven National Laboratory's Collider-Accelerator Department

  2. FEL in transverse optical klystron regime

    International Nuclear Information System (INIS)

    Scarlat, F.; Baltateanu, N.

    1994-01-01

    Among all operational regimes of free electron laser (FEL), the transverse optical regime (TOK) requires the least stringent electron beam parameters. The device associated to this regime, also defined as FEL with two or more components, consists of two or more identical interaction sections separated by one or more drift distances among themselves. Starting from the motion equations which describe the interaction between an electron and the radiation inside the undulator, one can obtain some practical expressions for the calculation of the efficiency of the energy transfer from the electron to the radiation, and the gain of the external coherent radiation for a FEL in TOK with three cavities. (Author)

  3. UV-VUV FEL program at DUKE storage ring with OK-4 optical klystron

    International Nuclear Information System (INIS)

    Litvinenko, V.N.; Madey, J.M.J.; Vinokurov, N.A.

    1993-01-01

    A 1 GeV electron storage ring dedicated for UV-VUV FEL operation is under construction at the Duke University Free Electron Laser Laboratory. The UV-VUV-FEL project, based on the collaboration of the Duke FEL Laboratory and Budker Institute for Nuclear Physics is described. The main parameters of the DFELL storage ring, of the OK-4 optical klystron, and the experimental set-up are presented. The parameters of UV-VUV FEL are given and the possible future upgrades to this system are discussed

  4. Study on wavelength shortening and upgrading of the free electron laser (FEL)

    International Nuclear Information System (INIS)

    Yamazaki, Tetsuo; Yamada, Kawakatsu; Sei, Norihiro; Ohgaki, Hideaki; Sugiyama, Suguru; Mikado, Tomohisa

    1997-01-01

    This study is a task of ''Comprehensive study'' in ''nuclear energy basic technology research'', which is promoted under cooperation of four research institutes. The Electrotechnical Laboratory conducted, in 1991 in the first period of colaboration, on successful oscillation at visible region (598 nm) as the first case in Japan, construction of small type accumulation ring NIJI-IV for FEL, successful oscillation of visible range from 595 to 488 nm by installing optical krystron with maximum frequency in the world, and successful emittance lowering of accumulation beam by wide improvement of the ring. In the optical resonator, studies on minute loss measuring technique and on recovery from mirror deterioration were promoted. In the second period started from fiscal year of 1994, studies on FEL oscillation technique in short wavelength and upgrading of FEL corresponding to a frontier area were started, to succeed an oscillation experiment at 350 nm in ultraviolet area on April, 1994. Then, studies on generation of high luminescence x-ray owing to laser Compton scattering using FEL as a future plan, on design of a new accumulation ring and on the others as well as studies on further quality improvement of electron beam and on optical resonator have been promoted. (G.K.)

  5. Future metrology needs for FEL reflective optics

    International Nuclear Information System (INIS)

    Assoufid, L.

    2000-01-01

    An International Workshop on Metrology for X-ray and Neutron Optics has been held March 16-17, 2000, at the Advanced Photon Source, Argonne National Laboratory, near Chicago, Illinois (USA). The workshop gathered engineers and scientists from both the U.S. and around the world to evaluate metrology instrumentation and methods used to characterize surface figure and finish for long grazing incidence optics used in beamlines at synchrotrons radiation sources. This two-day workshop was motivated by the rapid evolution in the performance of x-ray and neutron sources along with requirements in optics figure and finish. More specifically, the performance of future light sources, such as free-electron laser (FEL)-based x-ray sources, is being pushed to new limits in term of both brilliance and coherence. As a consequence, tolerances on surface figure and finish of the next generation of optics are expected to become tighter. The timing of the workshop provided an excellent opportunity to study the problem, evaluate the state of the art in metrology instrumentation, and stimulate innovation on future metrology instruments and techniques to be used to characterize these optics. This paper focuses on FEL optics and metrology needs. (A more comprehensive summary of the workshop can be found elsewhere.) The performance and limitations of current metrology instrumentation will be discussed and recommendations from the workshop on future metrology development to meet the FEL challenges will be detailed

  6. Future metrology needs for FEL reflective optics.

    Energy Technology Data Exchange (ETDEWEB)

    Assoufid, L.

    2000-09-21

    An International Workshop on Metrology for X-ray and Neutron Optics has been held March 16-17, 2000, at the Advanced Photon Source, Argonne National Laboratory, near Chicago, Illinois (USA). The workshop gathered engineers and scientists from both the U.S. and around the world to evaluate metrology instrumentation and methods used to characterize surface figure and finish for long grazing incidence optics used in beamlines at synchrotrons radiation sources. This two-day workshop was motivated by the rapid evolution in the performance of x-ray and neutron sources along with requirements in optics figure and finish. More specifically, the performance of future light sources, such as free-electron laser (FEL)-based x-ray sources, is being pushed to new limits in term of both brilliance and coherence. As a consequence, tolerances on surface figure and finish of the next generation of optics are expected to become tighter. The timing of the workshop provided an excellent opportunity to study the problem, evaluate the state of the art in metrology instrumentation, and stimulate innovation on future metrology instruments and techniques to be used to characterize these optics. This paper focuses on FEL optics and metrology needs. (A more comprehensive summary of the workshop can be found elsewhere.) The performance and limitations of current metrology instrumentation will be discussed and recommendations from the workshop on future metrology development to meet the FEL challenges will be detailed.

  7. Electron beam optics for the FEL experiment and IFEL experiment

    International Nuclear Information System (INIS)

    van Steenbergen, A.

    1990-01-01

    Electron beam transport system parameters for the FEL experiment and for the FEL experiment are given. The perturbation of the ''interaction region'' optics due to wiggler focussing is taken into account and a range of solutions are provided for relevant Twiss parameters in the FEL or IFEL region. Modifications of the transport optics in specific sections of the overall beam transport lines, for reasons of enhanced diagnostic capability or enhanced beam momentum analysis resolution, is also presented

  8. The GALAXIE all-optical FEL project

    Energy Technology Data Exchange (ETDEWEB)

    Rosenzweig, J. B.; Arab, E.; Andonian, G.; Cahill, A.; Fitzmorris, K.; Fukusawa, A.; Hoang, P.; Jovanovic, I.; Marcus, G.; Marinelli, A.; Murokh, A.; Musumeci, P.; Naranjo, B.; O' Shea, B.; O' Shea, F.; Ovodenko, A.; Pogorelsky, I.; Putterman, S.; Roberts, K.; Shumail, M. [Dept. of Physics and Astronomy, University of California, Los Angeles, 405 Hilgard Ave., Los Angeles, CA 90034 (United States); Dept. of Mechanical and Nuclear Engineering, Pennsylvania State University, University Park, PA 16802 (United States); Dept. of Physics and Astronomy, University of California, Los Angeles, 405 Hilgard Ave., Los Angeles, CA 90034 (United States); and others

    2012-12-21

    We describe a comprehensive project, funded under the DARPA AXiS program, to develop an all-optical table-top X-ray FEL based on dielectric acceleration and electromagnetic undulators, yielding a compact source of coherent X-rays for medical and related applications. The compactness of this source demands that high field (>GV/m) acceleration and undulation-inducing fields be employed, thus giving rise to the project's acronym: GV/m AcceLerator And X-ray Integrated Experiment (GALAXIE). There are numerous physics and technical hurdles to surmount in this ambitious scenario, and the integrated solutions include: a biharmonic photonic TW structure, 200 micron wavelength electromagnetic undulators, 5 {mu}m laser development, ultra-high brightness magnetized/asymmetric emittance electron beam generation, and SASE FEL operation. We describe the overall design philosophy of the project, the innovative approaches to addressing the challenges presented by the design, and the significant progress towards realization of these approaches in the nine months since project initialization.

  9. Optical properties of infrared FELs from the FELI Facility II

    Energy Technology Data Exchange (ETDEWEB)

    Saeki, K.; Okuma, S.; Oshita, E. [Free Electron Laser Institute, Osaka (Japan)] [and others

    1995-12-31

    The FELI Facility II has succeeded in infrared FEL oscillation at 1.91 {mu} m using a 68-MeV, 40-A electron beam from the FELI S-band linac in February 27, 1995. The FELI Facility II is composed of a 3-m vertical type undulator ({lambda}u=3.8cm, N=78, Km a x=1.4, gap length {ge}20mm) and a 6.72-m optical cavity. It can cover the wavelength range of 1-5{mu}m. The FELs can be delivered from the optical cavity to the diagnostics room through a 40-m evacuated optical pipeline. Wavelength and cavity length dependences of optical properties such as peak power, average power, spectrum width, FEL macropulse, FEL transverse profile are reported.

  10. Optics-free x-ray FEL oscillator

    International Nuclear Information System (INIS)

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

    2011-01-01

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

  11. Optics-free x-ray FEL oscillator

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-03-28

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

  12. Optical modeling of the Jefferson Lab IR Demo FEL

    International Nuclear Information System (INIS)

    Neil, G.; Benson, S.; Shinn, M.; Davidson, P.; Kloppel, P.

    1997-01-01

    The Thomas Jefferson National Accelerator Facility (formerly known as CEBAF) has embarked on the construction of a 1 kW free-electron laser operating initially at 3 microns that is designed for laser-material interaction experiments and to explore the feasibility of scaling the system in power and wavelength for industrial and Navy defense applications. The superconducting radio-frequency linac, and single-pass transport which accelerates the beam from injector to wiggler, followed by energy-recovery deceleration to a dump. The electron and optical beam time structure in the design consists of a train of pecosecond pulses at a 37.425 MHz pulse repetition rate. The initial optical configuration is a conventional near-concentric resonator with transmissive outcoupling. Future upgrades of the system will increase the power and shorten the operating wavelength, and utilize a more advanced resonator system capable of scaling to high powers. The optical system of the laser has been mode led using the GLAD code by using a Beer's-law region to mimic the FEL interaction. Effects such as mirror heating have been calculated and compared with analytical treatments. The magnitude of the distorium for several materials and wavelengths has been estimated. The advantages as well as the limitations of this approach are discussed

  13. Upgrade of a control system for the JAERI ERL-FEL

    International Nuclear Information System (INIS)

    Kikuzawa, Nobuhiro

    2004-01-01

    The accelerator control system used for the JAERI ERL-FEL is a PC-based distributed control system that has been in operation since 1992. Since an interface bus of the PCs is obsolete, interface boards for the PCs are difficult to obtain in recent years. Thus we have been developing the CAMAC controller with μITRON operating system to replace the old PCs connected with CAMAC. We will introduce a Java and CORBA environment in the new control system. The control system upgrade, including hardware upgrading and applications rewriting, is described in this paper. (author)

  14. Optical klystron FELs based on tandem electrostatic accelerators

    International Nuclear Information System (INIS)

    Gover, A.; Friedman, A.

    1989-01-01

    The operation of tandem electrostatic accelerator FELs in an optical klystron configuration makes it possible to take advantage of the high quality (low emittance and low energy spread) of the electron beam in electrostatic accelerators. With evolving microwiggler technology, state-of-the-art moderate energy (6-14-MeV) tandem electrostatic accelerators may be used for the development of highly coherent tunable radiation sources in the entire IR region. The authors present the general design considerations and the predicted operating characteristics of such devices and refer in specifics to a design of a 10-1000-μm FEL based on the parameters of a 5-6-MeV high current tandem accelerator. The operating wavelength of FELs is determined by the Doppler shift formula

  15. Physical optics simulations with PHASE for SwissFEL beamlines

    Energy Technology Data Exchange (ETDEWEB)

    Flechsig, U.; Follath, R.; Reiche, S. [Paul Scherrer Institut, Swiss Light Source, 5232 Villigen PSI (Switzerland); Bahrdt, J. [Helmholtz Zentrum Berlin (Germany)

    2016-07-27

    PHASE is a software tool for physical optics simulation based on the stationary phase approximation method. The code is under continuous development since about 20 years and has been used for instance for fundamental studies and ray tracing of various beamlines at the Swiss Light Source. Along with the planning for SwissFEL a new hard X-ray free electron laser under construction, new features have been added to permit practical performance predictions including diffraction effects which emerge with the fully coherent source. We present the application of the package on the example of the ARAMIS 1 beamline at SwissFEL. The X-ray pulse calculated with GENESIS and given as an electrical field distribution has been propagated through the beamline to the sample position. We demonstrate the new features of PHASE like the treatment of measured figure errors, apertures and coatings of the mirrors and the application of Fourier optics propagators for free space propagation.

  16. An advanced UV optical cavity for the European FEL project

    CERN Document Server

    Poole, M W; Chesworth, A A; Clarke, J A; Fell, B; Hill, C; Marl, R; Mullacrane, I D; Reid, R J

    2000-01-01

    A European collaboration is constructing a short wavelength FEL for the ELETTRA storage ring. The optical cavity has been designed and constructed at Daresbury Laboratory for delivery to Sincrotrone Trieste in Autumn 1999, following commissioning tests over the Summer. Initial FEL operation will be at 350 nm but subsequently down to 200 nm or less and mirrors will be 40 mm diameter. The 32 m optical cavity is controllable to 0.01 mu rad in mirror pitch and yaw using digital piezo translators. A novel feature is the simultaneous presence of three remotely interchangeable mirrors to extend the tuning range and also to interchange damaged mirrors immediately. In addition, a transfer arm and load-lock arrangement will permit a mirror to be withdrawn from the chamber and replaced without disruption to the UHV system. The FEL is designed to operate at high power (1-10 W) and multi-watt spontaneous emission is also present: power loading has been investigated by FEA analysis and has necessitated specification of a w...

  17. VUV Optics Development for the Elettra Storage Ring FEL

    CERN Document Server

    Guenster, Stefan

    2004-01-01

    Vacuum ultraviolet optical components for the storage ring FEL at Elettra are under continuous development in the European research consortium EUFELE. Target of the project is the progress to shorter lasing wavelengths in the VUV spectral range. The current status allows lasing with oxide mirror systems down to 190 nm. The main obstacles for the development of optical coatings for shorter wavelengths is the high energetic background of the synchrotron radiation impinging onto the front mirror in the laser cavity. Investigations in single layer systems and multilayer stacks of oxide or fluoride materials demonstrate that fluoride mirrors reach highest reflectivity values down to 140 nm, and oxide coatings possess a satisfactory resistance against the high energetic background irradiation. However, pure oxide multilayer stacks exhibit significant absorption below 190 nm and pure fluoride stacks suffer from strong degradation effects under synchrotron radiation. A solution could be hybrid systems, combining fluo...

  18. The Israeli EA-FEL Upgrade Towards Long Pulse Operation for Ultra-High Resolution Single Pulse Coherent Spectroscopy

    CERN Document Server

    Gover, A; Kanter, M; Kapilevich, B; Litvak, B; Peleg, S; Socol, Y; Volshonok, M

    2005-01-01

    The Israeli Electrostatic Accelerator FEL (EA-FEL) is now being upgraded towards long pulse (1005s) operation and ultra-high resolution (10(-6)) single pulse coherent spectroscopy. We present quantitative estimations regarding the applications of controlled radiation chirp for spectroscopic applications with pulse-time Fourier Transform limited spectral resolution. Additionally, we describe a novel extraction-efficiency-improving scheme based on increase of accelerating voltage (boosting) after saturation is achieved. The efficiency of the proposed scheme is confirmed by theoretical and numerical calculations. The latter are performed using software, based on 3D space-frequency domain model. The presentation provides an overview of the upgrade status: the high-voltage terminal is being reconfigured to accept the accelerating voltage boost system; a new broad band low-loss resonator is being manufactured; multi-stage depressed collector is assembled.

  19. Contributions to the FEL2005 conference

    Energy Technology Data Exchange (ETDEWEB)

    Grimm, O. (comp.)

    2005-07-01

    The following topics were dealt with: First lasing at 32 nm of the VUV-FEL at DESY, properties of the radiation from VUV-FEL at DESY, accelerator lay out and physics of X-ray free-electron lasers, bunch compression stability dependence on RF parameters, undulator systems and photon diagnostic for the European XFEL project, electron beam characterization at PITZ and the VUV-FEL at DESY, high precision optical synchronization systems for X-ray free electron lasers, optical laser synnchronized for the DESY VUV-FEL for two-color pump probe experiments, properties of the third harmonic of the SASE FEL radiation, detector response and beam line transmission measurements with far-infrared radiation, upgrades of the laser beam-line at PITZ, bunch length measurements using a Martin-Puplett interferometer at the VUV-FEL, next generation synchronization system for the VUV-FEL at DESY, transverse electron beam diagnostics at the VYV-FEL at DESY, the infrared undulator project at the VUV-FEL, misconceptions regarding second harmonic generation in X-ray free-electron lasers, influence of an energy chirp on SASE FEL operation, design considerations for the 4GLS XUV-FEL, broadband single shot spectrometer, commissioning of TTF2 bunch compressors for 20 fs SASE source, observation of femtosecond bunch length using a transverse deflecting structure, measurement of slice-emittance using a transverse deflecting structure, the injector of the VUV-FEL at DESY, spectral decoding electro-optic measurements for longitudinal bunch diagnostics at the DESY VUV-FEL, longitudinal phase space studies at PITZ, modelling the transverse phase space and core emittance studies at PITZ, measurements of thermal emittance for cesium telluride photocathodes at PITZ, status and first results from the upgraded PITZ facility, commissioning of the SPARC movable emittance meter and its first operation at PITZ. (HSI)

  20. Contributions to the FEL2005 conference

    International Nuclear Information System (INIS)

    Grimm, O.

    2005-01-01

    The following topics were dealt with: First lasing at 32 nm of the VUV-FEL at DESY, properties of the radiation from VUV-FEL at DESY, accelerator lay out and physics of X-ray free-electron lasers, bunch compression stability dependence on RF parameters, undulator systems and photon diagnostic for the European XFEL project, electron beam characterization at PITZ and the VUV-FEL at DESY, high precision optical synchronization systems for X-ray free electron lasers, optical laser synnchronized for the DESY VUV-FEL for two-color pump probe experiments, properties of the third harmonic of the SASE FEL radiation, detector response and beam line transmission measurements with far-infrared radiation, upgrades of the laser beam-line at PITZ, bunch length measurements using a Martin-Puplett interferometer at the VUV-FEL, next generation synchronization system for the VUV-FEL at DESY, transverse electron beam diagnostics at the VYV-FEL at DESY, the infrared undulator project at the VUV-FEL, misconceptions regarding second harmonic generation in X-ray free-electron lasers, influence of an energy chirp on SASE FEL operation, design considerations for the 4GLS XUV-FEL, broadband single shot spectrometer, commissioning of TTF2 bunch compressors for 20 fs SASE source, observation of femtosecond bunch length using a transverse deflecting structure, measurement of slice-emittance using a transverse deflecting structure, the injector of the VUV-FEL at DESY, spectral decoding electro-optic measurements for longitudinal bunch diagnostics at the DESY VUV-FEL, longitudinal phase space studies at PITZ, modelling the transverse phase space and core emittance studies at PITZ, measurements of thermal emittance for cesium telluride photocathodes at PITZ, status and first results from the upgraded PITZ facility, commissioning of the SPARC movable emittance meter and its first operation at PITZ. (HSI)

  1. Multi-mode competition in an FEL oscillator at perfect synchronism of an optical cavity

    CERN Document Server

    Dong, Z W; Kii, T; Yamazaki, T; Yoshikawa, K

    2002-01-01

    The sustained saturation in a short pulse free electron laser (FEL) oscillator at perfect synchronism of an optical cavity has been observed recently by Japan Atomic Energy Research Institute (JAERI) FEL group by using their super-conducting linac (Phys. Rev. Lett., in preparation). The experiments have clearly shown that FEL efficiency becomes maximum at perfect synchronism, although it has been considered that only a transient state exists at perfect synchronism due to the lethargy effect. Through careful analyses of the experimental condition of JAERI FEL, we found that, in spite of the short length of the electron micro-bunch, the saturation appears due to the following features, which were different from other FEL experiments: (1) very large ratio of the small signal gain to losses, (2) very long electron macro-bunch which can tolerate a slow start up. The saturation and high efficiency at perfect synchronism were benefited from the contribution of the weak sideband instability. In order to analyse these...

  2. Temporal characterization of FEL micropulses as function of cavity length detuning using frequency-resolved optical gating

    Energy Technology Data Exchange (ETDEWEB)

    Richman, B.A. [Stanford Univ., CA (United States); DeLong, K.W.; Trebino, R. [Sandia National Lab., Livermore, CA (United States)

    1995-12-31

    Results of frequency resolved optical gating (FROG) measurements on the Stanford mid-IR FEL system show the effect of FEL cavity length detuning on the micropulse temporal structure. The FROG technique enables the acquisition of complete and uniquely invertible amplitude and phase temporal dependence of optical pulses. Unambiguous phase and amplitude profiles are recovered from the data. The optical pulses are nearly transform limited, and the pulse length increases with cavity length detuning.

  3. A helical optical for circular polarized UV-FEL project at the UVSOR

    Energy Technology Data Exchange (ETDEWEB)

    Hama, Hiroyuki [Institute for Molecular Science, Okazaki (Japan)

    1995-12-31

    Most of existing storage ring free electron lasers (SRFEL) are restricted those performances by degradation of mirrors in optical cavities. In general, the SRFEL gain at the short wavelength region with high energy electrons is quite low, and the high reflectivity mirrors such as dielectric multilayer mirrors are therefore required. The mirror degradation is considered as a result of irradiation of higher harmonic photons that are simultaneously emitted from planar optical klystron (OK) type undulators, which are commonly used in SRFEL. This problem is getting severer as the lasing wavelength becomes shorter. The UVSOR-FEL had been originally scheduled to be shutdown by 1996 because another undulator project for spectroscopic studies with circular polarized photon would take the FEL`s place. According to suggestion of the insertion device group of the SPring-8, we have designed a helical undulator that is able to vary degree and direction of the polarization easily. In addition, the undulator can be converted into a helical OK by replacing magnets at the center part of undulator in order to coexist with further FEL experiments. Using a calculated magnetic field for magnet configurations of the OK mode, the radiation spectrum at wide wavelength range was simulated by a Fourier transform of Lienard-Wiechert potentials. As a matter of course, some higher harmonics are radiated on the off-axis angle. However it was found out that the higher harmonics is almost negligible as far as inside a solid angle of the Gaussian laser mode. Moreover the gain at the UV region of 250 nm is expected to be much higher than our present FEL because of high brilliant fundamental radiation. The calculated spatial distribution of higher harmonics and the estimated instantaneous gain is presented. Advantages of the helical OK for SRFEL will be discussed in view of our experience, and a possibility of application two-color experiment with SR will be also mentioned.

  4. Present and next steps of the JAERI superconducting rf linac based FEL program

    International Nuclear Information System (INIS)

    Minehara, E.J.; Yamauchi, T.; Sugimoto, M.

    2000-01-01

    The JAERI superconducting rf linac based FEL has successfully been lased to produce a 0.3 kW FEL light and 100 kW or larger electron beam output in quasi continuous wave operation in 1999. The 1 kW class output as our present program goal will be achieved to improve the optical out coupling method in the FEL optical resonator, the electron gun, and the electron beam optics in the JAERI FEL driver. As our next 5 year program goal is the 100 kW class FEL light and a few tens MW class electron beam output in average, quasi continuous wave operation of the light and electron beam will be planned in the JAERI superconducting rf linac based FEL facility. Conceptual design options needed for such a very high power operation and shorter wavelength light sources will be discussed to improve and to upgrade the exciting facility. (author)

  5. New autocorrelation technique for the IR FEL optical pulse width measurements

    Energy Technology Data Exchange (ETDEWEB)

    Amirmadhi, F.; Brau, K.A.; Becker, C. [Vanderbilt Univ., Nashville, TN (United States)] [and others

    1995-12-31

    We have developed a new technique for the autocorrelation measurement of optical pulse width at the Vanderbilt University FEL center. This method is based on nonlinear absorption and transmission characteristics of semiconductors such as Ge, Te and InAs suitable for the wavelength range from 2 to over 6 microns. This approach, aside being simple and low cost, removes the phase matching condition that is generally required for the standard frequency doubling technique and covers a greater wavelength range per nonlinear material. In this paper we will describe the apparatus, explain the principal mechanism involved and compare data which have been acquired with both frequency doubling and two-photon absorption.

  6. Transverse effects in UV FELs

    International Nuclear Information System (INIS)

    Small, D.W.; Wong, R.K.; Colson, W.B.

    1995-01-01

    In an ultraviolet Free Electron Laser (UV FEL), the electron beam size can be approximately the same as the optical mode size. The performance of a UV FEL is studied including the effect of emittance, betatron focusing, and external focusing of the electron beam on the transverse optical mode. The results are applied to the Industrial Laser Consortium's UV FEL

  7. FEL diagnostics and user control

    International Nuclear Information System (INIS)

    Knippels, G.M.H.; Meer, A.F.G. van der

    1998-01-01

    The most recent upgrades and improvements to the free-electron laser (FEL) facility FELIX are presented. Special attention is paid to the improved beam-handling and diagnostic station. In this evacuated beam station a device is implemented that is capable of selecting single micropulses with measured efficiencies of more than 50% over the whole wavelength range of FELIX (5-110 μm). Furthermore, the broadband autocorrelator for micropulse length measurements and the planned continuous polarization rotator based on reflective optics are discussed. Recent additions to the ancillary equipment available to FEL users are presented briefly. The most important ones are the mirror-dispersion-controlled 10-fs Ti:sapphire laser and the 40-T magnet. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  8. RF linacs for FELs

    International Nuclear Information System (INIS)

    Schwettman, H.A.

    1992-01-01

    There are twenty rf linac-driven Free Electron Lasers (FELs) existing or under construction throughout the world and proposals for several more. A number of these FELs have recently been established as facilities to produce coherent optical beams for materials and biomedical research. Both short pulse low duty factor and long pulse high duty factor linac-driven FELs will be discussed. Accelerator issues that influence the performance of an FEL as a scientific instrument will be indicated. (Author) 6 refs., 6 figs., 2 tabs

  9. Present status and future directions of the JAERI superconducting RF linac-based FEL

    International Nuclear Information System (INIS)

    Minehara, EJ.; Yamauchi, T.; Sugimori, M.; Sawamura, M.; Hajima, R.; Nagai, R.; Kikuzawa, N.; Nishimori, N.; Shizuma, T.

    2000-01-01

    The JAERI superconducting rf linac based FEL has successfully been lased to produce a 2.34kW FEL light and l00kW electron beam output in quasi continuous wave operation in February 2000. Twice larger output than the present program goal of 1kW was achieved to improve the optical out coupling method in the FEL optical resonator, the electron gun, and the electron beam optics in the JAERI FEL driver. As our next 2 years program goal is the 100kW class FEL light and a few MW class electron beam output in average, quasi continuous wave operation of the light and electron beam will be planned in the JAERI superconducting rf linac based FEL facility. Conceptual and engineering design options needed for such a very high power operation will be discussed to improve and to upgrade the existing facility. Finally, several applications, table-top superconducting rf linac based FELs, and an X-ray FEL R and D will be discussed as a next-five years program at JAERI-FEL laboratory. (author)

  10. Optical techniques for electron-beam characterizations on the APS SASE FEL project

    International Nuclear Information System (INIS)

    Lumpkin, A.H.; Yang, B.X.; Berg, W.J.; White, M.; Lewellen, J.W.; Milton, S.V.

    1998-01-01

    At the Advanced Photon Source (APS) the injector linac's DC thermionic gun is being supplemented by a low-emittance rf thermionic gun that will support the SASE FEL project. To address the anticipated smaller beam sizes, the standard Chromox beam-profiling screens are being complemented by optical transition radiation (OTR) and Ce-doped YAG single-crystal converters. Direct comparisons of the effective conversion efficiency, spatial resolution, and time response of the three converter screen types have been performed using the DC thermionic gun's beam accelerated to 400 to 650 MeV. An apparent blurring of observed beam size with increasing incident charge areal density in the YAG crystal was observed for the first time. Only the OTR was prompt enough for the few-ps domain micropulse bunch length measurements performed with a stream camera. Initial beam images of the rf-thermionic gun beam have also been obtained

  11. Cobra Fiber-Optic Positioner Upgrade

    Science.gov (United States)

    Fisher, Charles D.; Braun, David F.; Kaluzny, Joel V.

    2013-01-01

    A prime focus spectrometer (PFS), along with corrective optics, will mount in place of the secondary mirror of the Subaru telescope on Mauna Kea, Hawaii. This will allow simultaneous observations of cosmologic targets. It will enable large-scale galactic archeology and dark energy surveys to help unlock the secrets of the universe. To perform these cosmologic surveys, an array of 2,400 optical fibers needs to be independently positioned within the 498-mm-diameter focal plane of the PFS instrument to collect light from galaxies and stars for spectrographic analyses. To allow for independent re-positioning of the fibers, a very small positioner (7.7 mm in diameter) is required. One hundred percent coverage of the focal plane is also required, so these small actuators need to cover a patrol region of 9.5 mm in diameter. To optimize the amount of light that can be collected, the fibers need to be placed within 5 micrometers of their intended target (either a star or galaxy). The Cobra Fiber Positioner was designed to meet the size and accuracy requirements stated above. Cobra is a two-degrees-of-freedom mechanism that can position an optical fiber in the focal plane of the PFS instrument to a precision of 5 micrometers. It is a theta-phi style positioner containing two rotary piezo tube motors with one offset from the other, which enables the optic fibers to be placed anywhere in a small circular patrol region. The patrol region of the actuator is such that the array of 2,400 positioners allows for full coverage of the instrument focal plane by overlapping the patrol areas. A second-generation Cobra positioner was designed based on lessons learned from the original prototype built in 2009. Improvements were made to the precision of the ceramic motor parts, and hard stops were redesigned to minimize friction and prevent jamming. These changes resulted in reducing the number of move iterations required to position the optical fiber within 5 micrometers of its target. At

  12. Viability of infrared FEL facilities

    International Nuclear Information System (INIS)

    Schwettman, H.A.

    2004-01-01

    Infrared FELs have broken important ground in optical science in the past decade. The rapid development of optical parametric amplifiers and oscillators, and THz sources, however, has changed the competitive landscape and compelled FEL facilities to identify and exploit their unique advantages. The viability of infrared FEL facilities depends on targeting unique world-class science and providing adequate experimental beam time at competitive costs

  13. UPGRADES

    CERN Multimedia

    D. Contardo and J. Spalding

    2013-01-01

    The three post-LS1 Phase 1 Upgrade projects (the L1-Trigger, Pixel Tracker, and HCAL) are all making excellent progress and are transitioning from the prototype to the execution phase. Meanwhile plans are developing for Phase 2, a major Upgrade programme targeting the third long shutdown, LS3. News on Phase 1 is included under the respective projects; we only provide a brief summary here. Phase 1 The plan for the L1 Trigger relies on the installation during the present shutdown of optical splitting for the Trigger input signals. This will allow the new Trigger system to be brought online and fully commissioned during beam operation in 2015, while CMS relies on the existing legacy Trigger for physics. Once fully commissioned the experiment can switch over to the new Trigger, which will provide greatly improved performance at high event pile-up, by 2016. System tests of the splitter system, and of the new architecture of the calorimeter trigger were very successful, and the work in LS1 is on-track. Prototype ...

  14. Three dimensional modelling and numerical analysis of super-radiant harmonic emission in FEL (optical klystron)

    International Nuclear Information System (INIS)

    Gover, A.; Friedman, A.; Luccio, A.

    1986-09-01

    A full 3-D Analysis of super-radiant (bunched electron) free electron harmonic radiation is presented. A generalized form of the FEL pendulum equation was derived and numerically solved. Both spectral and phasor formulation were developed to treat the radiation in the time domain. In space the radiation field is expanded in terms of either a set of free space discrete modes or plane waves. The numerical solutions reveal some new distinctly 3-D effects to which we provide a physical explanation. 12 refs., 9 figs., 5 tabs

  15. A high-power compact regenerative amplifier FEL

    International Nuclear Information System (INIS)

    Nguyen, D.C.; Sheffield, R.L.; Fortgang, C.M.; Kinross-Wright, J.M.; Ebrahim, N.A.; Goldstein, J.C.

    1997-01-01

    The Regenerative Amplifier FEL (RAFEL) is a new FEL approach aimed at achieving the highest optical power from a compact rf-linac FEL. The key idea is to feed back a small fraction ( 5 in single pass) wiggler to enable the FEL to reach saturation in a few passes. This paper summarizes the design of a high-power compact regenerative amplifier FEL and describes the first experimental demonstration of the RAFEL concept

  16. UPGRADES

    CERN Multimedia

    J. Spalding and D. Contardo

    2012-01-01

      The CMS Upgrade Programme consists of four classes of projects: (a) Detector and Systems upgrades which are ongoing and largely (though not entirely) target LS1. (b) Full system upgrades for three projects that are preparing TDRs: Pixels, HCAL and L1 Trigger. The projects target completion by LS2. (c) Infrastructure consolidation and upgrades to improve operational robustness and to support the above projects. (d) Phase 2 replacement of the Tracker and major upgrades of the Trigger and Forward Detectors. For (a) and (c), detailed costing exists and is being integrated into a common reporting system. The schedule milestones for each project will be linked into the overall schedule planning for LS1. For the three TDR projects, the designs have progressed significantly since the Technical Proposal in 2010. Updated detailed cost estimates and schedules will be prepared with the TDRs to form the basis for tracking the projects through completion. To plan the upgrades and the supporting simulati...

  17. UPGRADES

    CERN Multimedia

    D. Contardo and J. Spalding

    2013-01-01

      LS1 and Phase 1 The detector projects targeting LS1 are progressing well, and a fully integrated schedule developed by Technical Coordination includes installation milestones and a detailed work-plan. The first chambers of the RPC system were produced and are being qualified. Production will ramp up this year to a rate of 20 chambers per month. 32 chambers of the CSC system have been fabricated for the ME4/2 CSC stations, and production proceeds at a rate of 4 per month. The new ME1/1 Front-End Board is in production and the off-detector electronics integration tests are ongoing. The new Theta Trigger Boards for the DT readout production is started and the relocation of the Sector Collector boards with new Optical Links as been successfully tested. All the components for the upgrade of the Forward Hadron Calorimeter PMTs have been received at CERN and assemblies are being qualified. The situation is similar for the Hadron Outer Calorimeter new SiPMs and readout modules. Three projects are plan...

  18. Super ACO FEL oscillation at 300 nm

    CERN Document Server

    Nutarelli, D; Renault, E; Nahon, L; Couprie, Marie Emmanuelle

    2000-01-01

    Some recent improvements, involving both the optical cavity mirrors and the positron beam dynamics in the storage ring, have allowed us to achieve a laser oscillation at 300 nm on the Super ACO Storage Ring FEL. The Super ACO storage ring is operated at 800 MeV which is the nominal energy for the usual synchrotron radiation users, and the highest energy for a storage ring FEL. The lasing at 300 nm could be kept during 2 h per injection, with a stored current ranging between 30 and 60 mA. The FEL characteristics are presented here. The longitudinal stability and the FEL optics behaviour are also discussed.

  19. Optics and lattice optimizations for the LHC upgrade project

    CERN Document Server

    Holzer, B; Chance, A; Dalena, B; Payet, J; Bogomyagkov, A; Appleby, R; Korostelev, M; Hock, K; Wolski, A; Milardi, C; Faus-Golfe, A; Resta, J

    2012-01-01

    The luminosity upgrade of the LHC collider at CERN is based on a strong focusing scheme to reach lowest values of the beta function at the collision points. Several issues have to be addressed in this context, that are considered as mid term goals for the optimisation of the lattice and beam optics: Firstly a number of beam optics have been developed to establish a baseline for the hardware R&D, and that will define the specifications for the new magnets that will be needed, in Nb$_{3}$Sn as well as in NbTi technology. Secondly, the need for sufficient flexibility of the beam optics especially for smallest β * values, the need for a smooth transition between the injection and the collision optics, the comparison of the optics performance between flat and round beams and finally different ways to optimise the chromatic correction, including the study of local correction schemes. This paper presents the status of this work, which is a result of an international collaboration, and summarises the main parame...

  20. UPGRADES

    CERN Multimedia

    J. Butler and J. Nash

    2011-01-01

    Recent progress on the CMS upgrades was summarised, in a workshop held at Fermilab between 7th and 10th November, attended by more than 150 people, many of whom came from Europe and Asia. Important goals of the workshop were to begin to formulate a schedule for the upgrades and to determine project interdependencies. Input was received from all the upgrade working groups and will be combined into a first-pass schedule over the next several weeks. In addition, technical progress on each of the major subtasks was presented and plans for the near-term future were established. Slides from the more than 100 talks are located at: https://indico.cern.ch/conferenceDisplay.py?confId=153564 In the opening plenary session, Frank Zimmermann, of the CERN Beams Department, gave his view of the LHC luminosity evolution. The luminosity will increase faster than we assumed in designing the upgrades. CMS will need to re-evaluate the current upgrade plans and revise them if necessary. CMS Upgrade Physics coordinator...

  1. Optical telescopes for COMPASS RICH1 up-grade

    CERN Document Server

    Sulc, M; Alekseev, M; Angerer, H; Appolonio, M; Birsa, R; Bordalo, P; Bradamante, F; Bressan, A; Busso, L; Chiosso, V M; Ciliberti, P; Colantoni, M L; Costa, S; Dibiase, N; Dafni, T; Dalla Torre, S; Diaz, V; Duic, V; Delagnes, E; Deschamps, H; Eyrich, W; Faso, D; Ferrero, A; Finger, M; Finger, M Jr; Fischer, H; Gerassimov, S; Giorgi, M; Gobbo, B; Hagemann, R; von Harrach, D; Heinsius, F H; Joosten, R; Ketzer, B; Königsmann, K; Kolosov, V N; Konorov, I; Kramer, D; Kunne, F; Levorato, S; Maggiora, A; Magnon, A; Mann, A; Martin, A; Menon, G; Mutter, A; Nähle, O; Neyret, D; Nerling, F; Pagano, P; Paul, S; Panebianco, S; Panzieri, D; Pesaro, G; Pizzolotto, C; Polak, J; Rebourgeard, P; Rocco, E; Robinet, F; Schiavon, P; Schill, C; Schoenmeier, P; Silva, L; Slunecka, M; Steiger, L; Sozzi, F; Svec, M; Tessarotto, F; Teufel, A; Wollny, H

    2006-01-01

    The central photon detection area of the Ring Imaging Cherenkov detector at COMPASS, a particle physics experiment at CERN SPS dedicated to hadron physics, has been upgraded from the previous system formed by wire chambers with CsI layers to a very fast UV extended multi anode photo multiplier tube array (MAPMT), including 576 tubes. The active area covered by the MAPMTs is 7.3 times smaller than the one previously equipped with CsI photocathodes, so 576 optical concentrators transforming the image from the old system focal plane to the new photocathode plane were needed. The telescope system formed by two fused silica lenses was designed, produced and assembled. The first prismatic plano-convex field lens is placed in the focal plane of the RICH mirrors. The second condenser lens is off centered and tilted and has one aspherical surface. All lenses have antireflection coating.

  2. FEL mirror response to shipboard vibrations

    OpenAIRE

    Beauvais, Joshua A.

    2011-01-01

    The Optical cavity of a Free Electron Laser (FEL) is composed of components that must be maintained to very tight tolerances. The shipboard environment is one that will preclude a direct coupling of FEL components to the ship. This thesis will explore the basis for these tight tolerances, and how to isolate them from the FEL. A solid model of a potential FEL system will be developed using SolidWorks. This model will then be converted to a finite element model in ANSYS. The finite element ...

  3. UPGRADES

    CERN Document Server

    D. Contardo and J. Spalding

    2013-01-01

    There is very good progress in the execution of the LS1 projects and in launching construction of the Phase 1 upgrades. We focus here on two main achievements since the last CMS Week. The approval of the third Phase 1 TDR The preparation of the L1 Trigger Upgrade Technical Design Report has been a major effort of the collaboration at the beginning of this year, especially to develop supporting Trigger menu and physics performance studies. These studies have demonstrated the efficiency of the upgraded system to ensure low lepton and jet trigger thresholds, leading to a significant increase of the acceptance for the Higgs measurements, in the associated production mode and in the ττ decays, as well as for the stop searches involving multiple jets in the final state. The TDR was submitted to the LHCC in May and approved at the June committee meeting. It is now a public document, completing the series of the three TDRs describing the Phase 1 upgrades, with the new Pixel system and the HCAL rea...

  4. THE VISA FEL UNDULATOR

    International Nuclear Information System (INIS)

    CARR, R.; CORNACCHIA, M.; EMMA, P.; NUHN, H.D.; FULAND, R.; JOHNSON, E.; RAKOWSKY, G.; LIDIA, S.; BERTOLINI, L.; LIBKIND, M.; FRIGOLA, P.; PELLEGRINI, C.; ROSENZWEIG, J.

    1998-01-01

    The Visible-Infrared SASE Amplifier (VISA) FEL is an experimental device designed to show Self Amplified Spontaneous Emission (SASE) to saturation in the visible light energy range. It will generate a resonant wavelength output from 800--600 nm, so that silicon detectors may be used to characterize the optical properties of the FEL radiation. VISA is the first SASE FEL designed to reach saturation, and its diagnostics will provide important checks of theory. This paper includes a description of the VISA undulator, the magnet measuring and shimming system, and the alignment strategy. VISA will have a 4 m pure permanent magnet undulator comprising four 99 cm segments, each with 55 periods of 18 mm length. The undulator has distributed focusing built into it, to reduce the average beta function of the 70--85 MeV electron beam to about 30 cm. There are four FODO cells per segment. The permanent magnet focusing lattice consists of blocks mounted on either side of the electron beam, in the undulator gap. The most important undulator error parameter for a free electron laser is the trajectory walkoff or lack of overlap of the photon and electron beams. Using pulsed wire magnet measurements and magnet shimming, the authors expect to be able to control trajectory walkoff to less than ±50 pm per field gain length

  5. UPGRADES

    CERN Multimedia

    D. Contardo and J. Spalding

    2012-01-01

      Good progress is being made on the projects that will be installed during LS1. CSC chamber production for ME4/2 is progressing at a rate of four chambers per month, with 25 built so far, and the new electronics for ME1/1 is undergoing a pre-production integration testing. For the RPC chambers, gap production is underway with first deliveries to the chamber assembly sites at CERN and Ghent. The third site at Mumbai will begin production next month. For the PMT replacement in the forward hadron calorimeters (HF), the 1728 PMTs are all characterised and ready to be installed. Testing of the electronics boards is going well. Preparations to replace the HPDs in the outer calorimeter (HO) with SiPMs are also on-track. All components are at CERN and burn-in of the new front-end electronics is proceeding. There are three major upgrade projects targeting the period from LS1 through LS2: a new pixel detector, upgraded photo-detectors and electronics for HCAL, and development of a new L1 Trigger. The new ...

  6. UPGRADES

    CERN Multimedia

    Didier Contardo

    2012-01-01

      The CMS Upgrade Programme is making good progress on the LS1 and Phase 1 projects, in the planning for Phase 2. The construction of the ME4/2 muon chambers to be installed during LS1 has started and the two first CSC production chambers have been fully qualified. The three muon groups have recently established a set of milestones towards the completion of their project, that will be integrated in the detailed planning and scheduling for the shutdown work established by Technical Coordination. The project to replace the photo-detectors in the HF and HO calorimeters is also well advanced and at the validation stage. The operation of an HF slice with new multi-anode PMTs and back-end electronics has already been demonstrated in 2012. For the Phase 1 data-taking, as discussed in the Chamonix workshop, it is likely that the LHC performance will exceed the nominal luminosity and pile-up before the second shutdown, still scheduled in 2018. The collaboration is therefore pursuing a strategy to upgrade ...

  7. In situ focus characterization by ablation technique to enable optics alignment at an XUV FEL source

    Czech Academy of Sciences Publication Activity Database

    Gerasimova, N.; Dziarzhytski, S.; Weigelt, H.; Chalupský, Jaromír; Hájková, Věra; Vyšín, Luděk; Juha, Libor

    2013-01-01

    Roč. 84, č. 6 (2013), "065104-1"-"065104-6" ISSN 0034-6748 R&D Projects: GA MŠk ED1.1.00/02.0061; GA MŠk EE.2.3.20.0087; GA ČR(CZ) GAP108/11/1312; GA ČR GAP205/11/0571; GA MŠk EE2.3.30.0057; GA MŠk(CZ) LG13029; GA ČR GAP208/10/2302; GA ČR GA13-28721S Grant - others:ELI Beamlines(XE) CZ.1.05/1.1.00/02.0061; OP VK 2 LaserGen(XE) CZ.1.07/2.3.00/20.0087; OP VK 4 POSTDOK(XE) CZ.1.07/2.3.00/30.0057; AVČR(CZ) M100101221 Institutional support: RVO:68378271 Keywords : free electron lasers * laser ablation * laser beams * optical focusing * ultraviolet sources Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.584, year: 2013

  8. Microfocusing of the FERMI@Elettra FEL beam with a K–B active optics system: Spot size predictions by application of the WISE code

    International Nuclear Information System (INIS)

    Raimondi, L.; Svetina, C.; Mahne, N.; Cocco, D.; Abrami, A.; De Marco, M.; Fava, C.; Gerusina, S.; Gobessi, R.; Capotondi, F.; Pedersoli, E.; Kiskinova, M.; De Ninno, G.; Zeitoun, P.; Dovillaire, G.; Lambert, G.; Boutu, W.; Merdji, H.; Gonzalez, A.I.; Gauthier, D.

    2013-01-01

    FERMI@Elettra, the first seeded EUV-SXR free electron laser (FEL) facility located at Elettra Sincrotrone Trieste has been conceived to provide very short (10–100 fs) pulses with ultrahigh peak brightness and wavelengths from 100 nm to 4 nm. A section fully dedicated to the photon transport and analysis diagnostics, named PADReS, has already been installed and commissioned. Three of the beamlines, EIS-TIMEX, DiProI and LDM, installed after the PADReS section, are in advanced commissioning state and will accept the first users in December 2012. These beam lines employ active X-ray optics in order to focus the FEL beam as well as to perform a controlled beam-shaping at focus. Starting from mirror surface metrology characterization, it is difficult to predict the focal spot shape applying only methods based on geometrical optics such as the ray tracing. Within the geometrical optics approach one cannot take into account the diffraction effect from the optics edges, i.e. the aperture diffraction, and the impact of different surface spatial wavelengths to the spot size degradation. Both these effects are strongly dependent on the photon beam energy and mirror incident angles. We employed a method based on physical optics, which applies the Huygens–Fresnel principle to reflection (on which the WISE code is based). In this work we report the results of the first measurements of the focal spot in the DiProI beamline end-station and compare them to the predictions computed with Shadow code and WISE code, starting from the mirror surface profile characterization

  9. Microfocusing of the FERMI@Elettra FEL beam with a K–B active optics system: Spot size predictions by application of the WISE code

    Energy Technology Data Exchange (ETDEWEB)

    Raimondi, L., E-mail: lorenzo.raimondi@elettra.trieste.it [Sincrotrone Trieste ScpA, S.S. 14 km 163.5 in Area Science Park, 34149 Trieste (Italy); Svetina, C.; Mahne, N. [Sincrotrone Trieste ScpA, S.S. 14 km 163.5 in Area Science Park, 34149 Trieste (Italy); Cocco, D. [SLAC National Accelerator Laboratory, 2575 Sand Hill Road, MS-19 Menlo Park, CA 94025 (United States); Abrami, A.; De Marco, M.; Fava, C.; Gerusina, S.; Gobessi, R.; Capotondi, F.; Pedersoli, E.; Kiskinova, M. [Sincrotrone Trieste ScpA, S.S. 14 km 163.5 in Area Science Park, 34149 Trieste (Italy); De Ninno, G. [Sincrotrone Trieste ScpA, S.S. 14 km 163.5 in Area Science Park, 34149 Trieste (Italy); University of Nova Gorica, Vipavska 13, Rozna Dolina, SI-5000 Nova Gorica (Slovenia); Zeitoun, P. [Laboratoire d' Optique Appliquée, CNRS-ENSTA-École Polytechnique, Chemin de la Humiére, 91761 Palaiseau (France); Dovillaire, G. [Imagine Optic, 18 Rue Charles de Gaulle, 91400 Orsay (France); Lambert, G. [Laboratoire d' Optique Appliquée, CNRS-ENSTA-École Polytechnique, Chemin de la Humiére, 91761 Palaiseau (France); Boutu, W.; Merdji, H.; Gonzalez, A.I. [Service des Photons, Atomes et Molécules, IRAMIS, CEA-Saclay, Btiment 522, 91191 Gif-sur-Yvette (France); Gauthier, D. [University of Nova Gorica, Vipavska 13, Rozna Dolina, SI-5000 Nova Gorica (Slovenia); and others

    2013-05-11

    FERMI@Elettra, the first seeded EUV-SXR free electron laser (FEL) facility located at Elettra Sincrotrone Trieste has been conceived to provide very short (10–100 fs) pulses with ultrahigh peak brightness and wavelengths from 100 nm to 4 nm. A section fully dedicated to the photon transport and analysis diagnostics, named PADReS, has already been installed and commissioned. Three of the beamlines, EIS-TIMEX, DiProI and LDM, installed after the PADReS section, are in advanced commissioning state and will accept the first users in December 2012. These beam lines employ active X-ray optics in order to focus the FEL beam as well as to perform a controlled beam-shaping at focus. Starting from mirror surface metrology characterization, it is difficult to predict the focal spot shape applying only methods based on geometrical optics such as the ray tracing. Within the geometrical optics approach one cannot take into account the diffraction effect from the optics edges, i.e. the aperture diffraction, and the impact of different surface spatial wavelengths to the spot size degradation. Both these effects are strongly dependent on the photon beam energy and mirror incident angles. We employed a method based on physical optics, which applies the Huygens–Fresnel principle to reflection (on which the WISE code is based). In this work we report the results of the first measurements of the focal spot in the DiProI beamline end-station and compare them to the predictions computed with Shadow code and WISE code, starting from the mirror surface profile characterization.

  10. On the upgrade of an optical code division PON with a code-sense ethernet MAC protocol

    NARCIS (Netherlands)

    Huiszoon, B.; Waardt, de H.; Khoe, G.D.; Koonen, A.M.J.

    2007-01-01

    We propose, for the first time, optical code-sense multiple access / collision detection to upgrade an optical code division passive optical network with minor modifications to transparently deploy Ethernet (or packet) based services.

  11. Observation of superradiance in a short-pulse FEL oscillator

    NARCIS (Netherlands)

    Jaroszynski, D. A.; Chaix, P.; Piovella, N.; Oepts, D.; Knippels, G.M.H.; van der Meer, A. F. G.; Weits, H. H.

    1997-01-01

    Superradiance has been experimentally studied, in a short-pulse free-electron laser (FEL) oscillator. Superradiance is the optimal way of extracting optical radiation from an FEL and can be characterised by the following scale laws: peak optical power P, scales as the square of electron charge, Q,

  12. Status and prospects of a compact FIR FEL driven by a magnetron-based microtron

    International Nuclear Information System (INIS)

    Jeong, Young Uk; Kazakevitch, Grigori M.; Lee, Byung Cheol; Kim, Sun Kook; Cho, Sung Oh; Gavrilov, Nicolai G.; Lee, Jongmin

    2002-01-01

    A magnetron-based microtron as a driver of FIR FEL has several prominent advantages in cost, size, beam quality and operation convenience. However, it has some disadvantages due to the instability of the RF frequency and a low current. In order to overcome these disadvantages, the frequency stability of the magnetron was improved, and the interaction between the electron beam and the FIR radiation was enhanced by using a high-performance undulator and a low-loss waveguide-mode optical resonator. The FEL is now under upgrade in order to extend the wavelength range to cover 90-300 μm, which can be done by increasing the energy range of electron beam to 4.3-7 MeV. In this paper, we report the results of investigations on output characteristics of the FEL depending on cavity detuning, electron beam matching, and RF instability. Based on the results, we discuss the prospects of wide-band FIR FELs driven by magnetron-based microtrons as potent sources of radiation for scientific applications

  13. Beam dynamics and optics studies for the LHC injectors upgrade

    CERN Document Server

    Bartosik, Hannes; Benedikt, Michael

    The Large Hadron Collider (LHC) upgrade, which aims at reaching significantly higher luminosities at the experiment sites, requires the existing injector chain to provide proton beams with unprecedented beam intensity and brightness. The required beam parameters are out of reach for the CERN accelerator complex in its present state. Therefore, upgrade possibilities of the existing injectors for mitigating their performance limitations or their partial replacement by new machines have been studied. The transition energy plays a central role for the performance of synchrotrons. Designing a lattice with negative momentum compaction (NMC), i.e. imaginary transition energy, allows avoiding transition crossing and thus the associated performance limitations. In the first part of this thesis, the properties of an NMC cell are studied. The limits of betatron stability are evaluated by a combination of analytical and numerical calculations. The NMC cell is then used for the design study of a new synchrotron called P...

  14. Investigations on a Q0 Doublet Optics for the LHC Luminosity Upgrade

    CERN Document Server

    Laface, E; Scandale, Walter; Wildner, E

    2008-01-01

    The Q0 scheme of the LHC insertion region is based on the introduction of a doublet of quadrupoles at 13 m from the IP. We present here the doublet optics and the magnets layout such as gradients, lengths, positions and apertures. In this scheme we show the gain in luminosity and chromaticity, with respect to a nominal layout with $\\beta^{*}$ = 0.25 m (i.e. LHC phase 1 upgrade) and $\\beta^{*} = 0.15 m, due to a smaller beta-max. We show the alignment tolerance and the energy deposition issues, in Q0A-Q0B. We also consider shielding the magnets with liners. The capability of Q0 optics to limit the b function could be exploited after the LHC Phase 1 upgrade in order to reduce the $\\beta^{*}$ below 0.25 m, leaving the upgraded triplet unchanged

  15. A scalable and continuous-upgradable optical wireless and wired convergent access network.

    Science.gov (United States)

    Sung, J Y; Cheng, K T; Chow, C W; Yeh, C H; Pan, C-L

    2014-06-02

    In this work, a scalable and continuous upgradable convergent optical access network is proposed. By using a multi-wavelength coherent comb source and a programmable waveshaper at the central office (CO), optical millimeter-wave (mm-wave) signals of different frequencies (from baseband to > 100 GHz) can be generated. Hence, it provides a scalable and continuous upgradable solution for end-user who needs 60 GHz wireless services now and > 100 GHz wireless services in the future. During the upgrade, user only needs to upgrade their optical networking unit (ONU). A programmable waveshaper is used to select the suitable optical tones with wavelength separation equals to the desired mm-wave frequency; while the CO remains intact. The centralized characteristics of the proposed system can easily add any new service and end-user. The centralized control of the wavelength makes the system more stable. Wired data rate of 17.45 Gb/s and w-band wireless data rate up to 3.36 Gb/s were demonstrated after transmission over 40 km of single-mode fiber (SMF).

  16. X-ray optics simulation and beamline design for the APS upgrade

    Science.gov (United States)

    Shi, Xianbo; Reininger, Ruben; Harder, Ross; Haeffner, Dean

    2017-08-01

    The upgrade of the Advanced Photon Source (APS) to a Multi-Bend Achromat (MBA) will increase the brightness of the APS by between two and three orders of magnitude. The APS upgrade (APS-U) project includes a list of feature beamlines that will take full advantage of the new machine. Many of the existing beamlines will be also upgraded to profit from this significant machine enhancement. Optics simulations are essential in the design and optimization of these new and existing beamlines. In this contribution, the simulation tools used and developed at APS, ranging from analytical to numerical methods, are summarized. Three general optical layouts are compared in terms of their coherence control and focusing capabilities. The concept of zoom optics, where two sets of focusing elements (e.g., CRLs and KB mirrors) are used to provide variable beam sizes at a fixed focal plane, is optimized analytically. The effects of figure errors on the vertical spot size and on the local coherence along the vertical direction of the optimized design are investigated.

  17. Observation of SASE in LEBRA FEL system

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, T. E-mail: tanaka@lebra.nihon-u.ac.jp; Hayakawa, K.; Sato, I.; Hayakawa, Y.; Yokoyama, K

    2004-08-01

    A large enhancement of spontaneous undulator radiation has been observed during FEL lasing experiments at LEBRA. The enhancement has been observed only with the detector for the infrared fundamental radiation. The detector output signal showed spikes during the electron beam pulse, yet no apparent enhancement was observed with a CCD camera monitoring the visible harmonic radiations. An enhancement factor greater than 10 has been obtained with a 2.4 m long undulator with a completely detuned FEL optical cavity length and depends strongly on the parameters of the linac RF system. This implies that the SASE operation is possible even with a conventional electron beam by achieving suitable bunch compression.

  18. Tunability and Power Characteristics of the LEBRA Infrared FEL

    CERN Document Server

    Tanaka, Toshinari; Hayakawa, Yasushi; Mori, Akira; Nogami, Kyoko; Sato, Isamu; Yokoyama, Kazue

    2004-01-01

    Application of the infrared (IR) Free-Electron Laser (FEL) was started in October 2003 at the Laboratory for Electron Beam Research and Application (LEBRA) of Nihon University. The FEL system consisted of silver-coated copper mirrors has demonstrated wavelength tunability ranged from 940 to 6100 nm as a function of the electron energy and the undulator K-value. Wavelength dependence of the FEL output power has been measured in term of different electron beam currents, electron energies and the undulator K-values. Approximate 25 mJ/macropulse has been obtained in the range 2 to 3 microns, which corresponds to peak power of 2 MW, provided that the FEL pulse length is 0.4 ps as resulted from the measurement by an interferometric method. The power decrease observed in the longer wavelength range is due to a large diffraction loss in the FEL guiding optics and the vacuum ducts.

  19. FEL components and diagnostics

    International Nuclear Information System (INIS)

    Carr, R.

    1997-01-01

    FEL hardware includes undulators, alignment systems, electron beam diagnostics, and mechanical and vacuum systems. While most FEL close-quote s employ conventional undulators, there is some interest in novel types, particularly where conventional designs cannot be used, as at very short periods and high fields. For these areas, superconducting technology is indicated. The most serious issue facing long FEL undulators is that of alignment; mechanical techniques may not be accurate enough, and beam-based strategies must be considered. To maintain alignment and control the electron trajectory, beam position monitors with micron precision are required. Beam size monitors are also required to assure control of emittance. The talks given in the working group sessions touch on undulators, alignment, and electron beam diagnostics, and they are summarized here. copyright 1997 American Institute of Physics

  20. Upgrade of the cathode strip chamber level 1 trigger optical links at CMS

    International Nuclear Information System (INIS)

    Ecklund, K; Liu, J; Matveev, M; Padley, P; Madorsky, A

    2012-01-01

    At the Large Hadron Collider (LHC) at CERN, the CMS experiment's Level 1 Trigger system for the endcap Cathode Strip Chambers (CSC) has 180 optical links to transmit Level 1 trigger primitives from 60 peripheral crates to the CSC Track Finder (CSCTF) which reconstructs muon candidates. Currently there is a limit of 3 trigger primitives per crate serving a cluster of 9 chambers. With the anticipated LHC luminosity increase up to 10 35 cm −2 s −1 at full energy of 7 TeV/beam the Muon Port Card (MPC), which transmits the primitives, the receiver in the CSCTF (Sector Processor) and the optical transmission system itself need to be upgraded. At the same time it is very desirable to preserve all the old optical links intact for compatibility with the present Track Finder during transition period. We present here the results of our efforts in the past two years to upgrade the MPC board, including the hardware developments, data transmission tests and latency measurements.

  1. Upgrade of optical WDM transport systems introducing linerates at 40 Gbit/s per channel

    Science.gov (United States)

    Schneiders, Malte; Vorbeck, Sascha; Aust, Nora

    2006-10-01

    Driven by high growth rates of internet traffic the question of upgrading existing optical metro-, regio- and long haul transport networks introducing 40 Gbit/s/λ is one of the most important questions today and in the near future. Current WDM Systems in photonic networks are commonly operated at linerates of 2.5 and 10 Gbit/s/λ. Induced by market analyses and the historical development of transport systems some work has already been carried out to evaluate update scenarios from 10 to 40 Gbit/s channel data rates. Due to the inherent quadruplication of the bandwidth per channel, limitations due to linear and non-linear transmission impairments become stronger resulting in a highly increased complexity of link engineering, potentially increasing the capital and operational expenditures. A lot of work is therefore in progress, which targets at the relaxation of constraints for 40 Gbit/s transmission to find the most efficient upgrade strategies. One approach towards an increased robustness against signal distortions is the introduction of more advanced modulation formats. Different modulation schemes show strongly different optical WDM transmission characteristics. The choice of the appropriate format does not only depend on the technical requirements, but also on economical considerations as an increased transmitter- and receiver-complexity will drive the transponder price. This article presents investigations on different modulation formats for the upgrade of existing metro-/ regio and long haul transport networks. Tolerances and robustness against the main degrading effects dispersion, noise and nonlinearities are considered together with mitigation strategies like the adaptation of dispersion maps. Results from numerical simulations are provided for some of the most promising modulation formats like NRZ, RZ, CS-RZ, Optical Duobinary and DPSK.

  2. The design of an optical link for the ATLAS Liquid Argon Calorimeter upgrade

    CERN Document Server

    Liu, T; The ATLAS collaboration

    2012-01-01

    We present the design of an optical link for the ATLAS liquid argon calorimeter upgrade. Challenging requirements are high data bandwidth (over 150 Gb/s raw data rate per board), radiation tolerance, low power consumption, high reliability, and low transmission latency. We discuss the link system design and component developments, especially those for the transmitting side that has to operate in the radiation environment. This presentation also serves as a summary of a few other presentations that detail in a particular function block of this link.

  3. Industrial Applications of High Average Power FELS

    CERN Document Server

    Shinn, Michelle D

    2005-01-01

    The use of lasers for material processing continues to expand, and the annual sales of such lasers exceeds $1 B (US). Large scale (many m2) processing of materials require the economical production of laser powers of the tens of kilowatts, and therefore are not yet commercial processes, although they have been demonstrated. The development of FELs based on superconducting RF (SRF) linac technology provides a scaleable path to laser outputs above 50 kW in the IR, rendering these applications economically viable, since the cost/photon drops as the output power increases. This approach also enables high average power ~ 1 kW output in the UV spectrum. Such FELs will provide quasi-cw (PRFs in the tens of MHz), of ultrafast (pulsewidth ~ 1 ps) output with very high beam quality. This talk will provide an overview of applications tests by our facility's users such as pulsed laser deposition, laser ablation, and laser surface modification, as well as present plans that will be tested with our upgraded FELs. These upg...

  4. Fibre optics cabling design for LHC detectors upgrade using variable radiation induced attenuation model

    CERN Document Server

    Shoaie, Mohammad Amin; Machado, Simao; Ricci, Daniel

    2018-01-01

    Foreseen upgrades over the next decades enable LHC to operate at a higher luminosity (HL-LHC). Accordingly, the optical links designed to transmit particle collision data need to be hardened against increased radiation level, allowing for a reliable communication. In this paper we study the fibre cabling design of a link between the transceiver optical front-end and the data control room. The radiation penalty calculation takes temperature drop down to ‒30°C into account. The proposed solution concatenates radiation-resistance and conventional fibres using multi-fibre interconnections. The end-to-end link loss during HL-LHC lifetime is estimated strictly less than 3.5 dB complying with predefined margin.

  5. Optics Designs of Final-Focus Systems for Future LHC Upgrades

    CERN Document Server

    Abelleira, J L; Zimmermann, Frank; Rivkin, Leonid

    2014-01-01

    The main topic of the thesis is the study of a novel option for the high-luminosity upgrade of the Large Hadron Collider (LHC) comprising a large Piwinski angle, flat beams, and crab waists. Flat beams and crab waists are not only pre-requisites for a crab-waist scheme, but, even by themselves; each of these two elements alone could boost the luminosity of the existing collider as built. The new optics involves an upgrade of the interaction region of the two high-luminosity experiments, ATLAS and CMS, in order to provide them with a substantially higher luminosity. To this end, a flat-beam optics scenario has been explored for the High Luminosity LHC (HL-LHC), with a much reduced vertical beta function at the interaction point (IP), $\\beta_y^*$. In addition, a large Piwinski angle is considered. Advantages of a large Piwinski angle include a reduction in the hourglass effect over the length of the collision area, which allows for the significant $\\beta_y^*$ decrease. In addition there is a reduction of the be...

  6. The SwissFEL Experimental Laser facility.

    Science.gov (United States)

    Erny, Christian; Hauri, Christoph Peter

    2016-09-01

    The hard X-ray laser SwissFEL at the Paul Scherrer Institute is currently being commissioned and will soon become available for users. In the current article the laser facility is presented, an integral part of the user facility, as most time-resolved experiments will require a versatile optical laser infrastructure and precise information about the relative delay between the X-ray and optical pulse. The important key parameters are a high availability and long-term stability while providing advanced laser performance in the wavelength range from ultraviolet to terahertz. The concept of integrating a Ti:sapphire laser amplifier system with subsequent frequency conversion stages and drift compensation into the SwissFEL facility environment for successful 24 h/7 d user operation is described.

  7. High-power, high-efficiency FELs

    International Nuclear Information System (INIS)

    Sessler, A.M.

    1989-04-01

    High power, high efficiency FELs require tapering, as the particles loose energy, so as to maintain resonance between the electromagnetic wave and the particles. They also require focusing of the particles (usually done with curved pole faces) and focusing of the electromagnetic wave (i.e. optical guiding). In addition, one must avoid transverse beam instabilities (primarily resistive wall) and longitudinal instabilities (i.e sidebands). 18 refs., 7 figs., 3 tabs

  8. Performance of the upgraded LTP-II at the ALS Optical Metrology Laboratory

    International Nuclear Information System (INIS)

    Advanced Light Source; Yashchuk, Valeriy V; Kirschman, Jonathan L.; Domning, Edward E.; McKinney, Wayne R.; Morrison, Gregory Y.; Smith, Brian V.; Yashchuk, Valeriy V.

    2008-01-01

    The next generation of synchrotrons and free electron laser facilities requires x-ray optical systems with extremely high performance, generally of diffraction limited quality. Fabrication and use of such optics requires adequate, highly accurate metrology and dedicated instrumentation. Previously, we suggested ways to improve the performance of the Long Trace Profiler (LTP), a slope measuring instrument widely used to characterize x-ray optics at long spatial wavelengths. The main way is use of a CCD detector and corresponding technique for calibration of photo-response non-uniformity [J. L. Kirschman, et al., Proceedings of SPIE 6704, 67040J (2007)]. The present work focuses on the performance and characteristics of the upgraded LTP-II at the ALS Optical Metrology Laboratory. This includes a review of the overall aspects of the design, control system, the movement and measurement regimes for the stage, and analysis of the performance by a slope measurement of a highly curved super-quality substrate with less than 0.3 microradian (rms)slope variation

  9. The 'Fresh-Bunch' technique in FELs

    International Nuclear Information System (INIS)

    Ben-Zvi, I.; Yang, K.M.; Yu, L.H.

    1991-01-01

    The 'Fresh Bunch' technique is being proposed as a method of increasing the gain and power of FEL amplifiers in which the length of the optical radiation pulse is shorter than the length of the electron bunch. In multi-stage FEL, electron beam energy spread is increased by the FEL interaction in the early stages. In the 'Fresh Bunch' technique, the low energy spread of the electron beam is recovered by shifting the radiation pulse to an undisturbed part of the electron bunch, thus improving the gain and trapping fraction in later stages. A test case for the application of the Fresh Bunch method is demonstrated by numerical simulation. In this particular example we examine a subharmonically seeded VUV Free-Electron Laser. We begin with the generation of harmonic radiation, which takes place over one part of the electron bunch. Then the radiation is shifted by means of a strong dispersive section to a fresh part of the bunch for exponential amplification and tapered wiggler amplification. By starting over with a new ensemble of electrons, the energy spread introduced by the bunching in the fundamental is removed, leading to an increased gain. Furthermore, it is possible to use a much stronger seed in the fundamental without incurring the penalty of a large energy spread later on. We note that more than a single application of the 'Fresh Bunch' method may be done in a single FEL multiplier-amplifier. Thus x-ray wavelengths may be reached by successive multiplication in a chain of FEL amplifiers starting from a tunable seed laser. 5 refs., 2 figs., 2 tabs

  10. Tapered undulators for SASE FELs

    CERN Document Server

    Fawley, W M; Vinokurov, N A

    2002-01-01

    We discuss the use of tapered undulators to enhance the performance of free-electron lasers (FELs) based upon self-amplified spontaneous emission, where the radiation tends to have a relatively broad bandwidth and limited temporal coherence. Using the polychromatic FEL simulation code GINGER, we numerically demonstrate the effectiveness of tapered undulators for parameters corresponding to the Argonne low-energy undulator test line FEL and the proposed linac coherent light source.

  11. THz Imaging by a Wide-band Compact FEL

    CERN Document Server

    Uk Jeong Young; Cheol Lee Byung; Hee-Park, S

    2004-01-01

    We have developed a laboratory-scale users facility with a compact THz FEL. The FEL operates in the wide wavelength range of 100–1200 μm, which corresponds to 0.3-3 THz. THz radiation from the FEL shows well collimated Gaussian spatial distribution and narrow spectral width of 0.3 μm, which is Fourier transform limited by the estimated pulse duration of 20 ps. The main application of the FEL is THz imaging for bio-medical researches. We are developing THz imaging techniques by 2-D scanning, single pulse capturing with the electro-optic method, and 3-D holography. High power, coherent, and pulsed feature of the FEL radiation is expected to show much better performance in advanced THz imaging of 3-D tomography by comparing with incoherent and weak THz sources. By controlling the optical delay between reference beam and scattered light from an object, we can get its 3-D tomography by the holograms. The coherent and pulse length of the FEL beam is measured to be 3-6 mm. In this paper we will show a...

  12. FEL options for power beaming

    International Nuclear Information System (INIS)

    Kim, K.J.; Zholents, A.A.; Zolotorev, M.S.; Vinokurov, N.A.

    1997-10-01

    The demand for the output power of communication satellites has been increasing exponentially. The satellite power is generated from solar panels which collect the sunlight and convert it to electrical power. The power per satellite is limited due to the limit in the practical size of the solar panel. One way to meet the power demand is to employ multiple satellites (up to 10) per the internationally agreed-upon ''slot'' in the geosynchronous earth orbit (GEO). However, this approach is very expensive due to the high cost of sending a satellite into a GEO orbit. An alternative approach is power beaming, i.e., to illuminate the solar panels with high power, highly-directed laser beams from earth. The power beaming generates more power per satellite for the same area of the solar panel. The minimum optical beam power, interesting for power beaming application, is P L = 200kW. The wavelength is chosen to be λ 0.84 microm, so that it is within one of the transmission windows of the air, and at the same time near the peak of the photo-voltaic conversion efficiency of Si, which is the commonly used material for the solar panels. Free electron lasers (FELs) are well suited for the power beaming application because they can provide high power with coherent wavefront, but without high energy density in media. In this article the authors discuss some principal issues, such as the choice of accelerator and electron gun, the choice of beam parameters, radiation hazards, technological availability, and overall efficiency and reliability of the installation. They also attempt to highlight the compromise between the cost of the primary installation, the operation cost, and the choice of technology, and its maturity. They then present several schemes for the accelerator-FEL systems based on RF accelerators. The initial electron beam accelerator up to the energy of a few MeV is more or less common for all these schemes

  13. Layout and Optics Solution for the LHC Insertion Upgrade Phase I

    CERN Document Server

    Fartoukh, S

    2010-01-01

    The main guidelines of the LHC IR upgrade Phase I project are the development of wider aperture (120 mm) and lower gradient (120 T/m) quadrupoles using the wellcharacterized Nb-Ti technology in order to build new inner triplets (IT) for the ATLAS and CMS experimental insertions, while minimizing the hardware modifications in the other parts of these insertions, in particular leaving unchanged the so-called "matching section" (MS) and "dispersion suppressor" (DS). While one of the initial goal was to squeeze the optics down to a B* of 25 cm, optics solutions with a B* of 30 cm are already at the edge of feasibility, both in terms of the IT and MS mechanical acceptance, gradients of the MS and DS quadrupole magnets, and correctability by the arc sextupoles of the huge chromatic aberrations generated at low B*. The layout of the new inner triplet and the corresponding injection and collision optics will be presented and analyzed in terms of aperture and chromatic correction.

  14. Short wavelength FELs using the SLAC linac

    International Nuclear Information System (INIS)

    Winick, H.; Bane, K.; Boyce, R.

    1993-08-01

    Recent technological developments have opened the possibility to construct a device which we call a Linac Coherent Light Source (LCLS); a fourth generation light source, with brightness, coherence, and peak power far exceeding other sources. Operating on the principle of the free electron laser (FEL), the LCLS would extend the range of FEL operation to much aborter wavelength than the 240 mn that has so far been reached. We report the results of studies of the use of the SLAC linac to drive an LCLS at wavelengths from about 3-100 nm initially and possibly even shorter wavelengths in the future. Lasing would be achieved in a single pass of a low emittance, high peak current, high energy electron beam through a long undulator. Most present FELs use an optical cavity to build up the intensity of the light to achieve lasing action in a low gain oscillator configuration. By eliminating the optical cavity, which is difficult to make at short wavelengths, laser action can be extended to shorter wavelengths by Self-Amplified-Spontaneous-Emission (SASE), or by harmonic generation from a longer wavelength seed laser. Short wavelength, single pass lasers have been extensively studied at several laboratories and at recent workshops

  15. Short wavelength FELS

    International Nuclear Information System (INIS)

    Sheffield, R.L.

    1991-01-01

    The generation of coherent ultraviolet and shorter wavelength light is presently limited to synchrotron sources. The recent progress in the development of brighter electron beams enables the use of much lower energy electron rf linacs to reach short-wavelengths than previously considered possible. This paper will summarize the present results obtained with synchrotron sources, review proposed short- wavelength FEL designs and then present a new design which is capable of over an order of magnitude higher power to the extreme ultraviolet. 17 refs., 10 figs

  16. Short wavelength FELS

    Energy Technology Data Exchange (ETDEWEB)

    Sheffield, R.L.

    1991-01-01

    The generation of coherent ultraviolet and shorter wavelength light is presently limited to synchrotron sources. The recent progress in the development of brighter electron beams enables the use of much lower energy electron rf linacs to reach short-wavelengths than previously considered possible. This paper will summarize the present results obtained with synchrotron sources, review proposed short- wavelength FEL designs and then present a new design which is capable of over an order of magnitude higher power to the extreme ultraviolet. 17 refs., 10 figs.

  17. Analysis of the FEL-RF interaction in recirculating, energy-recovering linacs with an FEL

    International Nuclear Information System (INIS)

    Merminga, L.; Alexeev, P.; Benson, S.; Bolshakov, A.; Doolittle, L.; Neil, G.

    1999-01-01

    Recirculating, energy-recovering linacs can be used as driver accelerators for high power FELs. Instabilities which arise from fluctuations of the cavity fields are investigated. Energy changes can cause beam loss on apertures, phase oscillations and optical cavity detuning. These effects in turn cause changes in the laser output power through a time-varying FEL gain function. All three effects change the beam-induced voltage in the cavities and can lead to unstable variations of the accelerating field and output laser power. We have developed a model of the coupled system and solved it both analytically and numerically. It includes the beam-cavity interaction, low level RF feedback, and the electron-photon interaction. The latter includes the FEL gain function in terms of cavity detuning, energy offset, and is valid both in the small signal gain and in the saturated regimes. We have demonstrated that in the limit of small perturbations, the linear theory agrees with the numerical solutions and have performed numerical simulations for the IR FEL presently being commissioned at Jefferson Lab

  18. Analysis of the FEL-RF interaction in recirculating energy-recovering linacs with an FEL

    International Nuclear Information System (INIS)

    Merminga, Lia; Alexeev, P.; Benson, Steve; Bolshakov, A.; Doolittle, Lawrence; Neil, George

    1999-01-01

    Recirculating, energy-recovering linacs can be used as driver accelerators for high power FELs. Instabilities which arise from fluctuations of the cavity fields are investigated. Energy changes can cause beam loss on apertures, phase oscillations and optical cavity detuning. These effects in turn cause changes in the laser output power through a time-varying FEL gain function. All three effects change the beam-induced voltage in the cavities and can lead to unstable variations of the accelerating field and output laser power. We have developed a model of the coupled system and solved it both analytically and numerically. It includes the beam-cavity interaction, low level RF feedback, and the electron-photon interaction. The latter includes the FEL gain function in terms of cavity detuning, energy offset, and is valid both in the small signal gain and in the saturated regimes. We have demonstrated that in the limit of small perturbations, the linear theory agrees with the numerical solutions and have performed numerical simulations for the IR FEL presently being commissioned at Jefferson Lab

  19. Analysis of the FEL-RF interaction in recirculating, energy-recovering linacs with an FEL

    Energy Technology Data Exchange (ETDEWEB)

    Merminga, L. E-mail: merminga@jlab.org; Alexeev, P.; Benson, S.; Bolshakov, A.; Doolittle, L.; Neil, G

    1999-06-01

    Recirculating, energy-recovering linacs can be used as driver accelerators for high power FELs. Instabilities which arise from fluctuations of the cavity fields are investigated. Energy changes can cause beam loss on apertures, phase oscillations and optical cavity detuning. These effects in turn cause changes in the laser output power through a time-varying FEL gain function. All three effects change the beam-induced voltage in the cavities and can lead to unstable variations of the accelerating field and output laser power. We have developed a model of the coupled system and solved it both analytically and numerically. It includes the beam-cavity interaction, low level RF feedback, and the electron-photon interaction. The latter includes the FEL gain function in terms of cavity detuning, energy offset, and is valid both in the small signal gain and in the saturated regimes. We have demonstrated that in the limit of small perturbations, the linear theory agrees with the numerical solutions and have performed numerical simulations for the IR FEL presently being commissioned at Jefferson Lab.

  20. Interpretation of the electron cyclotron emission of hot ASDEX upgrade plasmas at optically thin frequencies

    Energy Technology Data Exchange (ETDEWEB)

    Denk, Severin Sebastian; Stroth, Ulrich [Max-Planck-Institut fuer Plasmaphysik, D-85748 Garching (Germany); Physik-Department E28, Technische Universitaet Muenchen, 85748 Garching (Germany); Fischer, Rainer; Poli, Emanuele; Willensdorfer, Matthias; Maj, Omar; Stober, Joerg; Suttrop, Wolfgang [Max-Planck-Institut fuer Plasmaphysik, D-85748 Garching (Germany); Collaboration: The ASDEX Upgrade Team

    2016-07-01

    The electron cyclotron emission diagnostic (ECE) provides routinely electron temperature (T{sub e}) measurements. ''Kinetic effects'' (relativistic mass shift and Doppler shift) can cause the measured radiation temperatures (T{sub rad}) to differ from T{sub e} at cold resonance position complicating the determination of T{sub e} from the measured radiation temperature profile (T{sub rad}). For the interpretation of such ECE measurements an electron cyclotron forward model solving the radiation transport equation for given T{sub e} and electron density profiles is in use in the framework of Integrated Data Analysis at ASDEX Upgrade. While the original model lead to improved T{sub e} profiles near the plasma edge in moderately hot H-mode discharges, vacuum approximations in the model lead to inaccuracies given large T{sub e}. In hot plasmas ''wave-plasma interaction'', i.e. the dielectric effect of the background plasma onto the electron cyclotron emission, becomes important at optical thin measured frequencies. Additionally, given moderate electron densities and large T{sub e}, the refraction of the line of sight has to be considered for the interpretation of ECE measurements with low optical depth.

  1. A proposed visible FEL Facility at Boeing

    Energy Technology Data Exchange (ETDEWEB)

    Dowell, D.H.; Adamski, J.L.; Hayward, T.D. [Boeing Defense & Space Group, Seattle, WA (United States)] [and others

    1995-12-31

    A 1-kW average power, visible wavelength FEL is described, based on a 120-MeV, 0.1. A macropulse average current linac operating at a duty factor of 0. 6% and having average beam power of 70 kW. The accelerator will employ a demonstrated photoinjector, 18-MeV, 433-MHz linac as an injector, followed by a 1300-MHz longitudinal phase space {open_quotes} linearizer,{close_quotes} a magnetic buncher chicane, and seven 1300-MHz, pulsed traveling wave linac sections. The magnets used to transport the beam from the linac to the FEL centerline, the 5-m THUNDER wiggler, and the optical resonator will be reclaimed from previous FEL demonstration experiments. We expect to attain pulse lengths of 7 ps for 3.5 nC, with minimal distortion of the pulse profile and normalized rms emittance of 7.5 {+-} 2.5 {pi} mm-mr. FELEX projects a laser conversion efficiency of 4.3 %, yielding average output of 3 kW.

  2. Towards short wavelengths FELs workshop

    International Nuclear Information System (INIS)

    Ben-Zvi, I.; Winick, H.

    1993-01-01

    This workshop was caged because of the growing perception in the FEL source community that recent advances have made it possible to extend FEL operation to wavelengths about two orders of magnitude shorter than the 240 nm that has been achieved to date. In addition short wavelength FELs offer the possibilities of extremely high peak power (several gigawatts) and very short pulses (of the order of 100 fs). Several groups in the USA are developing plans for such short wavelength FEL facilities. However, reviewers of these plans have pointed out that it would be highly desirable to first carry out proof-of-principle experiments at longer wavelengths to increase confidence that the shorter wavelength devices will indeed perform as calculated. The need for such experiments has now been broadly accepted by the FEL community. Such experiments were the main focus of this workshop as described in the following objectives distributed to attendees: (1) Define measurements needed to gain confidence that short wavelength FELs will perform as calculated. (2) List possible hardware that could be used to carry out these measurements in the near term. (3) Define a prioritized FEL physics experimental program and suggested timetable. (4) Form collaborative teams to carry out this program

  3. Towards short wavelengths FELs workshop

    Science.gov (United States)

    Ben-Zvi, I.; Winick, H.

    1993-11-01

    This workshop was caged because of the growing perception in the FEL source community that recent advances have made it possible to extend FEL operation to wavelengths about two orders of magnitude shorter than the 240 nm that has been achieved to date. In addition short wavelength FEL's offer the possibilities of extremely high peak power (several gigawatts) and very short pulses (of the order of 100 fs). Several groups in the USA are developing plans for such short wavelength FEL facilities. However, reviewers of these plans have pointed out that it would be highly desirable to first carry out proof-of-principle experiments at longer wavelengths to increase confidence that the shorter wavelength devices will indeed perform as calculated. The need for such experiments has now been broadly accepted by the FEL community. Such experiments were the main focus of this workshop as described in the following objectives distributed to attendees: (1) Define measurements needed to gain confidence that short wavelength FEL's will perform as calculated. (2) List possible hardware that could be used to carry out these measurements in the near term. (3) Define a prioritized FEL physics experimental program and suggested timetable. (4) Form collaborative teams to carry out this program.

  4. The "TEU-FEL" project

    OpenAIRE

    Ernst, G.J.; Witteman, W.J.; Verschuur, Jeroen W.J.; Mols, R.F.X.A.M.; Mols, R.F.X.A.M.; van Oerle, B.M.; van Oerle, B.M.; Bouman, A.F.M.; Botman, J.I.M.; Hagedoorn, H.L.; Delhez, J.L.; Kleeven, W.J.G.M.

    1995-01-01

    The free-electron laser of the TEU-FEL project will be based on a 6 MeV photo-cathode linac as injector, a 25 MeV race-track microtron as main accelerator and a hybrid, 25 mm period undulator. The project will be carried out in two phases. In phase one only the 6 MeV linac will be used, The FEL will then produce tunable radiation around 200 µm. In phase two the linac will be used as an injector for the microtron. The FEL will then produce tunable radiation around 10 µm. Technical information ...

  5. Radiation-hard ASICs for optical data transmission in the first phase of the LHC upgrade

    International Nuclear Information System (INIS)

    Gan, K.K.; Buchholz, P.; Kagan, H.P.; Kass, R.D.; Moore, J.R.; Smith, D.S.; Wiese, A.; Ziolkowskic, M.

    2011-01-01

    We have designed two ASICs for possible applications in the optical links of a new layer of the pixel detector to be install inside the ATLAS Pixel detector for the first phase of the LHC luminosity upgrade. The ASICs include a high-speed driver for a VCSEL and a receiver/decoder to decode the signal received at a PIN diode to extract the data and clock. Both ASICs contain 4 channels for operation with a VCSEL or PIN array. The ASICs were designed using a 130 nm CMOS process to enhance the radiation-hardness. We have characterized the fabricated ASICs and the performance of the ASICs is satisfactory. The receiver/decoder properly decodes the bi-phase marked input stream with low PIN current and the driver can operate a VCSEL up to ∼5 Gb/s. The added functionalities are also successful, including redundancy to bypass a broken VCSEL or PIN channel, individual control of VCSEL current, and power-on reset circuit to set all VCSEL currents to a nominal value.

  6. Radiation-hard ASICs for optical data transmission in the first phase of the LHC upgrade

    International Nuclear Information System (INIS)

    Gan, K K; Kagan, H P; Kass, R D; Moore, J R; Smith, D S; Buchholz, P; Wiese, A; Ziolkowskic, M

    2010-01-01

    We have designed two ASICs for possible applications in the optical links of a new layer of the pixel detector to be install inside the ATLAS Pixel detector for the first phase of the LHC luminosity upgrade. The ASICs include a high-speed driver for the VCSEL and a receiver/decoder to decode the signal received at the PIN diode to extract the data and clock. Both ASICs contain 4 channels for operation with a VCSEL or PIN array. The ASICs were designed using a 130 nm CMOS process to enhance the radiation-hardness. We have characterized the fabricated ASICs and the performance of the ASICs is satisfactory. The receiver/decoder can properly decode the bi-phase marked input stream with low PIN current and the driver can operate a VCSEL up to ∼ 5 Gb/s. The added functionalities are also successful, including redundancy to bypass a broken VCSEL or PIN channel, individual control of VCSEL current, and power-on reset circuit to set all VCSEL currents to a nominal value. The ASICs were irradiated to a dose of 46 Mrad with 24 GeV/c protons. The observed modest degradation is acceptable and the single event upset rate is negligible.

  7. Radiation-hard ASICs for optical data transmission in the first phase of the LHC upgrade

    CERN Document Server

    Gan, K K; Kagan, H P; Kass, R D; Moore, J R; Smith, D S; Wiese, A; Ziolkowskic, M; 10.1088/1748-0221/5/12/C12006

    2010-01-01

    We have designed two ASICs for possible applications in the optical links of a new layer of the pixel detector to be install inside the ATLAS Pixel detector for the first phase of the LHC luminosity upgrade. The ASICs include a high-speed driver for the VCSEL and a receiver/decoder to decode the signal received at the PIN diode to extract the data and clock. Both ASICs contain 4 channels for operation with a VCSEL or PIN array. The ASICs were designed using a 130 nm CMOS process to enhance the radiation-hardness. We have characterized the fabricated ASICs and the performance of the ASICs is satisfactory. The receiver/decoder can properly decode the bi-phase marked input stream with low PIN current and the driver can operate a VCSEL up to ~ 5 Gb/s. The added functionalities are also successful, including redundancy to bypass a broken VCSEL or PIN channel, individual control of VCSEL current, and power-on reset circuit to set all VCSEL currents to a nominal value. The ASICs were irradiated to a dose of 46 Mrad ...

  8. Optics Challenges and Solutions for the LHC Insertion Upgrade Phase I

    CERN Document Server

    Fartoukh, S

    2010-01-01

    The goal of the LHC Insertion (IR) Upgrade Phase-I is to enable a reliable operation of the machine with a performance at least doubled with respect to its design luminosity. One key ingredient is ideally a reduction of Beta* down to 25 cm, using a new inner triplet (IT) with longer Nb-Ti quadrupoles operating at a lower gradient (~ 120 T/m) and therefore offering a larger aperture (120 mm). Reducing Beta*, but also operating at a lower IT gradient (which, at a given Beta*, further increases the size of the Beta-functions all over the long straight section), has however a certain number of drawbacks which cannot be solved by only increasing the aperture of the new low-beta quadrupoles. Without modifying the current layout of the matching section (MS) and assuming that the arc sextupoles cannot safely operate above nominal current (550A), optics solutions with a Beta* of 30 cm are already at the edge of feasibility, both in terms of mechanical aperture in the MS and new IT (assuming 120 mm aperture), in terms ...

  9. Performance of the advanced cold neutron source and optics upgrades at the NIST Research Reactor

    International Nuclear Information System (INIS)

    Williams, R.E.; Kopetka, P.; Cook, J.C.; Rowe, J.M.

    2003-01-01

    On March 6, 2002, the NIST Research Reactor resumed routine operation following a six-month shutdown for facility upgrades and maintenance. During the shutdown, the original liquid hydrogen cold neutron source was removed, and the advanced cold source was installed. An optical filter was installed on one of the neutron guides, NG-3, replacing a crystal filter for the 30-m SANS instrument and the guide used between the chopper disks of the Disk Chopper time-of-flight Spectrometer (DCS) installed on NG-4 has been recently reconfigured. Additional improvements in the neutron optics of various instruments are being made. The advanced liquid hydrogen cold neutron source performs as expected, nearly doubling the flux available to most instruments. The measured gains range from about 1.4 at 2 A, to over a factor of two at 15 A. Also as expected, the heat load in the new source increased to 1200 watts, but the previously existing refrigerator has easily accommodated the increase. With intensity gains of a factor of two in the important long wavelength region of the spectrum, the advanced cold source significantly enhances the measurement capability of the cold neutron scattering instrumentation at NIST. The optical filter on NG-3 is also very successful; the 30-m SANS has an additional gain of two at 17 A. A system of refracting lenses and prisms near the SANS sample position has made possible measurements at low Q (0.0005 A -1 ) that were previously not feasible. The DCS has also seen additional intensity gain factors in excess of two for the majority of experiments and at short neutron wavelengths the gains exceed three. In addition, two new triple axis spectrometers will feature double-focusing monochromators in order to exploit the full size of the available thermal and cold neutron beam tubes. The success of the advanced cold source and enhanced neutron optics contributed to the recognition of the NIST Center for Neutron Research as 'the premiere neutron scattering

  10. The "TEU-FEL" project

    NARCIS (Netherlands)

    Ernst, G.J.; Witteman, W.J.; Verschuur, Jeroen W.J.; Mols, R.F.X.A.M.; Mols, R.F.X.A.M.; van Oerle, B.M.; van Oerle, B.M.; Bouman, A.F.M.; Botman, J.I.M.; Hagedoorn, H.L.; Delhez, J.L.; Kleeven, W.J.G.M.

    1995-01-01

    The free-electron laser of the TEU-FEL project will be based on a 6 MeV photo-cathode linac as injector, a 25 MeV race-track microtron as main accelerator and a hybrid, 25 mm period undulator. The project will be carried out in two phases. In phase one only the 6 MeV linac will be used, The FEL will

  11. Introduction: a short-wavelength-FEL/storage-ring complex

    International Nuclear Information System (INIS)

    Sessler, A.M.

    1984-01-01

    We believe that, in view of the present state of FEL understanding, it is now proper to construct a research facility devoted to the use of coherent radiation and the advancement of FEL physics technology at wavelengths shorter than 1000 A. We show a possible layout of such a facility, which will be referred to as a Coherent xuv Facility (CXF), where research can be conducted on several techniques for generating coherent radiation. Undulators are already well understood and will generate broadly tunable, spatially coherent radiation of bandwidth lambda /Δlambda approx. = 10 2 . A crossed undulator system will extend the undulator capability to include variable polarization. For full coherence, in spatial as well as in longitudinal directions, it is necessary to induce and exploit density modulation in electron beams, as is the case in the transverse optical klystrons (TOKs) and FELs. In TOKs, coherent radiation is generated at harmonics of an input laser frequency, with the electron beam playing the role of a nonlinear medium. Ultimately, FELS would deliver intense, tunable x rays and vuv radiation of extremely narrow spectral width. There are two possible routes to an FEL, one based on feedback by end mirrors, the other based on development of a high-gain, single-pass device. It can be seen, from this paper, that the photon flux increases monotonically, or the wavelength decreases monotonically, as one goes through (1) undulator radiation, (2) TOK radiation, (3) FEL oscillator radiation, to (4) FEL single-pass radiation. Each of these will demand considerable quality development effort. Each will result in photon fluxes of increased value to the users

  12. Review of High Gain FELs

    International Nuclear Information System (INIS)

    Shintake, Tsumoru

    2007-01-01

    For understanding on basic radiation mechanism of the high-gain FEL based on SASE, the author presents electron-crystal interpretation of FEL radiation. In the electron-crystal, electrons are localized at regularly spaced multi-layers, which represents micro-bunching, whose spacing is equal to the radiation wavelength, and the multi-layers are perpendicular to beam axis, thus, diffracted wave creates Bragg's spots in forward and backward directions. Due to the Doppler's effect, frequency of the back-scattered wave is up-converted, generates forwardly focused X-ray. The Bragg's effect contributes focusing the X-ray beam into a spot, thus peak power becomes extremely higher by factor of typically 107. This is the FEL radiation. As well known, the total numbers of scattered photons in Bragg's spots is equal to the total elastic scattering photons from the atoms contained in the crystal. Therefore, total power in the FEL laser is same as the spontaneous radiation power from the undulator for the same beam parameter. The FEL radiation phenomenon is simple interference effect. In today's presentations, we use the laser pointer, and we frequently experience difficulty in pointing precisely or steadily in one place on the screen, since the laser spot is very small and does not spread. Exactly same to this, X-ray FEL is a highly focused beam, and pointing stability dominates productivity of experiment, thus we need special care on beam stability from linear accelerator

  13. FEL-Oscillator simulations with Genesis 1.3

    NARCIS (Netherlands)

    Karssenberg, J.G.; van der Slot, Petrus J.M.; Verschuur, Jeroen W.J.; Volokhine, I.; Boller, Klaus J.

    2006-01-01

    Modeling free-electron laser (FEL) oscillators requires calculation of both the light-beam interaction within the undulator and the propagation of the light outside the undulator. We present a paraxial Optical Propagation Code (OPC) based on the Spectral Method and Fresnel Diffraction Integral,

  14. The FEL development at the Advanced Photon Source

    International Nuclear Information System (INIS)

    Arnold, N. D.; Benson, C.; Berg, S.; Berg, W.; Biedron, S. G.; Chae, Y. C.; Crosbie, E. A.; Decker, G.; Dejus, R. J.; Den Hartog, P.; Deriy, B.; Dortwegt, R.; Edrmann, M.; Freund, H. P.; Friedsam, H.; Galayda, J. N.; Gluskin, E.; Goeppner, G. A.; Grelick, A.; Huang, Z.; Jones, J.; Kang, Y.; Kim, K.-J.; Kim, S.; Kinoshita, K.; Lewellen, J. W.; Lill, R.; Lumpkin, A. H.; Makarov, O.; Markovich, G. M.; Milton, S. V.; Moog, E. R.; Nassiri, A.; Ogurtsov, V.; Pasky, S.; Power, J.; Tieman, B.; Trakhtenberg, E.; Travish, G.; Vasserman, I.; Walters, D. R.; Wang, J.; Xu, S.; Yang, B.

    1999-01-01

    Construction of a single-pass free-electron laser (FEL) based on the self-amplified spontaneous emission (SASE) mode of operation is nearing completion at the Advanced Photon Source (APS) with initial experiments imminent. The APS SASE FEL is a proof-of-principle fourth-generation light source. As of January 1999 the undulator hall, end-station building, necessary transfer lines, electron and optical diagnostics, injectors, and initial undulatory have been constructed and, with the exception of the undulatory, installed. All preliminary code development and simulations have also been completed. The undulator hall is now ready to accept first beam for characterization of the output radiation. It is the project goal to push towards fill FEL saturation, initially in the visible, but ultimately to W and VUV, wavelengths

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

    Energy Technology Data Exchange (ETDEWEB)

    Michelle D. Shinn

    2007-08-26

    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.

  16. Performance of the FEL cryomodules

    International Nuclear Information System (INIS)

    Drury, M.; Fischer, J.; Preble, J.

    1998-01-01

    The Thomas Jefferson National Accelerator Facility (Jefferson Lab, formerly known as CEBAF) is building a highly efficient, kilowatt-level infrared free-electron laser, the IR Demo FEL. The IR FEL uses superconducting radio-frequency (SRF) cavities to accelerate the electron beam that provides energy for the laser. These cavities provide the high-gradient acceleration for the high average currents necessary for a compact FEL design. Currently, a quarter cryomodule injector and a full eight-cavity cryomodule have been installed in the FEL linac. These units were tested as part of the IR FEL commissioning process. The main focus of these tests was to determine the maximum stable operating gradient. The average maximum gradient reached by these ten cavities was 11 Mv/m. Other tests include measurement of cavity parameters such as the unloaded Q (Qo) vs. gradient, the input coupling, calibration of field probes and behavior of the tuner mechanisms. This paper presents the results of those tests

  17. Analysis of the FEL-RF interaction in recirculating, energy-recovering linacs with an FEL

    CERN Document Server

    Merminga, L; Benson, S; Bolshakov, A; Doolittle, L; Neil, George R

    1999-01-01

    Recirculating, energy-recovering linacs can be used as driver accelerators for high power FELs. Instabilities which arise from fluctuations of the cavity fields are investigated. Energy changes can cause beam loss on apertures, phase oscillations and optical cavity detuning. These effects in turn cause changes in the laser output power through a time-varying FEL gain function. All three effects change the beam-induced voltage in the cavities and can lead to unstable variations of the accelerating field and output laser power. We have developed a model of the coupled system and solved it both analytically and numerically. It includes the beam-cavity interaction, low level RF feedback, and the electron-photon interaction. The latter includes the FEL gain function in terms of cavity detuning, energy offset, and is valid both in the small signal gain and in the saturated regimes. We have demonstrated that in the limit of small perturbations, the linear theory agrees with the numerical solutions and have performed...

  18. Issues at a university based FEL center

    International Nuclear Information System (INIS)

    Smith, T.I.; Schwettman, H.A.

    1998-01-01

    The Stanford FEL Center was established in September 1990. In this paper, the FEL itself, the Center infrastructure, the interaction with experimenters and the educational mission are described. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  19. The PixFEL project: development of advanced X-ray pixel detectors for application at future FEL facilities

    International Nuclear Information System (INIS)

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

    2015-01-01

    The PixFEL project aims to develop an advanced X-ray camera for imaging suited for the demanding requirements of next generation free electron laser (FEL) facilities. New technologies can be deployed to boost the performance of imaging detectors as well as future pixel devices for tracking. In the first phase of the PixFEL project, approved by the INFN, the focus will be on the development of the microelectronic building blocks, carried out with a 65 nm CMOS technology, implementing a low noise analog front-end channel with high dynamic range and compression features, a low power ADC and high density memory. At the same time PixFEL will investigate and implement some of the enabling technologies to assembly a seamless large area X-ray camera composed by a matrix of multilayer four-side buttable tiles. A pixel matrix with active edge will be developed to minimize the dead area of the sensor layer. Vertical interconnection of two CMOS tiers will be explored to build a four-side buttable readout chip with small pixel pitch and all the on-board required functionalities. The ambitious target requirements of the new pixel device are: single photon resolution, 1 to 10 4 photons @ 1 keV to 10 keV input dynamic range, 10-bit analog to digital conversion up to 5 MHz, 1 kevent in-pixel memory and 100 μm pixel pitch. The long term goal of PixFEL will be the development of a versatile X-ray camera to be operated either in burst mode (European XFEL), or in continuous mode to cope with the high frame rates foreseen for the upgrade phase of the LCLS-II at SLAC

  20. FEL-principles, techniques and its progress

    International Nuclear Information System (INIS)

    Zhao Xiaofeng; Yang Fujia

    1992-01-01

    The basic principles of free electron laser (FEL) and its operation modes are presented. The state of the art is described for accelerator technology and laser systems. Some comparisons are made between FEL and conventional laser with regard to power capability, short-wavelength operation, and tunability. The application prospects of FEL are discussed

  1. Shielding for the upgraded duke free electron laser laboratory

    International Nuclear Information System (INIS)

    Vylet, V.

    2005-01-01

    The Duke FEL Laboratory is undergoing a series of upgrades staggered over time that will greatly increase the capabilities of the machines and by the same token the importance of radiation safety issues. In this paper, we present the scope of the planned upgrades and provide several specific examples of shielding calculations. We also present our effort to correlate calculations with experimental measurements. (authors)

  2. FEL gain optimisation and spontaneous radiation

    Energy Technology Data Exchange (ETDEWEB)

    Bali, L.M.; Srivastava, A.; Pandya, T.P. [Lucknow Univ. (India)] [and others

    1995-12-31

    Colson have evaluated FEL gains for small deviations from perfect electron beam injection, with radiation of the same polarisation as that of the wiggler fields. We find that for optimum gain the polarisation of the optical field should be the same as that of the spontaneous emission under these conditions. With a helical wiggler the axial oscillations resulting from small departures from perfect electron beam injection lead to injection dependent unequal amplitudes and phases of the spontaneous radiation in the two transverse directions. Viewed along the axis therefore the spontaneous emission is elliptically polarised. The azimuth of the ellipse varies with the difference of phase of the two transverse components of spontaneous emission but the eccentricity remains the same. With planar wigglers the spontaneous emission viewed in the axial direction is linearly polarised, again with an injection dependent azimuth. For optimum coherent gain of a radiation field its polarisation characteristics must be the same as those of the spontaneous radiation with both types of wiggler. Thus, with a helical wiggler and the data reported earlier, an increase of 10% in the FEL gain at the fundamental frequency and of 11% at the fifth harmonic has been calculated in the small gain per pass limit. Larger enhancements in gain may result from more favourable values of input parameters.

  3. Optimization of a high efficiency FEL amplifier

    International Nuclear Information System (INIS)

    Schneidmiller, E.A.; Yurkov, M.V.

    2014-10-01

    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.

  4. The upgrade of the multiwire drift chamber readout of the HADES experiment at GSI: the optical end point board

    Energy Technology Data Exchange (ETDEWEB)

    Tarantola, Attilio; Michel, Jan; Muentz, Christian; Stroth, Joachim [Institut fuer Kernphysik, Goethe-Universitaet, Frankfurt (Germany); GSI, Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); Froehlich, Ingo; Stroebele, Herbert [Institut fuer Kernphysik, Goethe-Universitaet, Frankfurt (Germany); Kolb, Burkhard; Traxler, Michael [GSI, Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); Palka, Marek [Smoluchowski Institute of Physics, Jagiellonian University, Krakow (Poland); GSI, Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); Wuestenfeld, Joern [Institut fuer Strahlenphysik, Forschungszentrum, Dresden-Rossendorf (Germany)

    2009-07-01

    One of the goal of the HADES upgrade project is the realization of a new data acquisition scheme for the 24 Multiwire Drift Chambers (MDCs), which allows to increase the readout speed of the 40.000 TDC channels. On the existing MDC Front End Electronic (FEE) side an Optical End Point Board (OEPB) has been designed to control configuration and readout of the chamber's TDCs. The OEPB uses Plastic Optical Fibres (POF) for data transmission, which results in total electromagnetic immunity, amazing simplicity in handling and low power consumption. The employment of a Lattice ECP2/M FPGA with SERDES manages serial data transmission and its large resources allow for the storage of several events close-to-front-end. As 400 OEPBs will be located in the detector acceptance, dedicated FPGA hardware is used to detect Single Event Upsets (SEUs).

  5. Aging and environmental tolerance of an optical transmitter for the ATLAS Phase-I upgrade at the LHC

    Energy Technology Data Exchange (ETDEWEB)

    Chang, F.X. [Academia Sinica, Taipei, Taiwan (China); Chang, H.T. [Liverage Technology Inc., Chupei, Taiwan (China); Duh, T.S. [Institute of Nuclear Energy Research, Longtan, Taiwan (China); Hayamizu, T. [CYRIC, Tohoku University, Sendai (Japan); Hou, S. [Academia Sinica, Taipei, Taiwan (China); Hu, X. [Michigan University, Ann Arbor, MI (United States); Liu, C.; Liu, T. [Southern Methodist University, Dallas, TX (United States); Sakemi, Y. [CYRIC, Tohoku University, Sendai (Japan); Schwarz, T. [Michigan University, Ann Arbor, MI (United States); Teng, P.K.; Tsai, P.R. [Academia Sinica, Taipei, Taiwan (China); Wang, C.H. [National United University, Miaoli, Taiwan (China); Wang, S.Y. [Liverage Technology Inc., Chupei, Taiwan (China); Yang, Y. [National Cheng Kung University, Tainan, Taiwan (China); Ye, J. [Southern Methodist University, Dallas, TX (United States)

    2016-09-21

    The dual channel Miniature optical Transmitter (MTx) is developed for the ATLAS Phase-I upgrade requiring durable performance in the Large Hadron Collider environment. The data transmission has achieved 8 Gbps per channel with a custom-designed LOCld laser driver and 850 nm VCSELs packaged in transmitter optical sub-assemblies (TOSAs). The performance of the MTx opto-electronics is evaluated. Accelerated aging tests of the VCSELs were conducted in a chamber at 85 °C, 85% relative humidity, with TOSA and bare-die samples prepared in non-hermetic condition. Radiation tolerance of the VCSELs was investigated with 30 MeV and 70 MeV protons. The radiation induced effects in data transmission were investigated for light-power degradation and parameters of eye-diagrams.

  6. FELs, nice toys or efficient tools?

    CERN Document Server

    Van der Meer, Alex F G

    2004-01-01

    An FEL is an intrinsically interesting device and pushing its performance presents a natural challenge to a physicist. Nonetheless, the main justification for doing FEL research is of course its potential as a unique, versatile source of radiation to be employed for something useful. After 25 years of FEL research, one may wonder how efficient these tools have become. In this paper, I will reflect on this issue from the perspective of 10 years of operation of FELIX as a user facility.

  7. Sustained lasing of HHG-seeded FEL by using EOS-based timing control

    International Nuclear Information System (INIS)

    Watanabe, Takahiro; Okayasu, Yuichi; Togashi, Tadashi; Hara, Toru; Tomizawa, Hiromitsu; Matsubara, Shinichi; Aoyama, Makoto; Yamakawa, Koichi; Iwasaki, Atsushi; Ohwada, Shigeki; Sato, Takahiro; Yamauchi, Kaoru; Otake, Yuji; Ohshima, Takashi; Ogawa, Kanade; Togawa, Kazuaki; Tanaka, Takashi; Takahashi, Eiji; Midorikawa, Katsumi; Yabashi, Makina; Tanaka, Hitoshi; Ishikawa, Tetsuya

    2013-01-01

    High-harmonic-generation (HHG) based seeded FEL experiments were demonstrated at SCSS, SPring-8. Seeded FEL has advantageous features against SASE such that there is no intrinsic nature of shot-noise fluctuation and output FEL pulses are in principle fully coherent in both transverse and longitudinal axes. In practical user experiments, however, an overlap between electron bunches and seed laser pulses in six-dimensional phase space needs to be precisely maintained for securing the stable lasing. Otherwise, the overlap could be quickly lost and the lasing is no more sustained. For the stable lasing, we have developed an EO (electro-optic) based timing control system, which enables to observe a timing drift between electron bunches and laser pulses, and compensate for it. Experimental results of the seeded FEL with and without the EO timing control are compared, and the effectiveness of the timing system is discussed. (author)

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

    International Nuclear Information System (INIS)

    Corlett, J.; Byrd, J.; Fawley, W.M.; Gullans, M.; Li, D.; Lidia, S.M.; Padmore, H.; Penn, G.; Pogorelov, I.; Qiang, J.; Robin, D.; Sannibale, F.; Staples, J.W.; Steier, C.; Venturini, M.; Virostek, S.; Wan, W.; Wells, R.; Wilcox, R.; Wurtele, J.; Zholents, A.

    2007-01-01

    We report on design studies for a seeded FEL light source that is responsive to the scientific needs of the future. The FEL process increases radiation flux by several orders of magnitude above existing incoherent sources, and offers the additional enhancements attainable by optical manipulations of the electron beam: control of the temporal duration and bandwidth of the coherent output, reduced gain length in the FEL, utilization of harmonics to attain shorter wavelengths, and precise synchronization of the x-ray pulse with seed laser systems. We describe an FEL facility concept based on a high repetition rate RF photocathode gun, that would allow simultaneous operation of multiple independent FEL's, each producing high average brightness, tunable over the VUV-soft x-ray range, and each with individual performance characteristics determined by the configuration of the FEL. SASE, enhanced-SASE (ESASE), seeded, harmonic generation, and other configurations making use of optical manipulations of the electron beam may be employed, providing a wide range of photon beam properties to meet varied user demands

  9. Lattice Design for a High-Power Infrared FEL

    Science.gov (United States)

    Douglas, D. R.

    1997-05-01

    A 1 kW infrared FEL, funded by the U.S. Navy, is under construction at Jefferson Lab. This device will be driven by a compact, 42 MeV, 5 mA, energy-recovering, CW SRF-based linear accelerator to produce light in the 3-6.6 μm range. The machine concept comprises a 10 MeV injector, a linac based on a single high-gradient Jefferson Lab accelerator cryomodule, a wiggler and optical cavity, and an energy-recovery recirculation arc. Energy recovery limits cost and technical risk by reducing the RF power requirements in the driver accelerator. Following deceleration to 10 MeV, the beam is dumped. Stringent phase space requirements at the wiggler, low beam energy, and high beam current subject the accelerator lattice to numerous constraints. Principal considerations include: transport and delivery to the FEL of a high-quality, high-current beam; the impact of coherent synchrotron radiation (CSR) during beam recirculation transport; beam optics aberration control, to provide low-loss energy-recovery transport of a 5% relative momentum spread, high-current beam; attention to possible beam breakup (BBU) instabilities in the recirculating accelerator; and longitudinal phase space management during beam transport, to optimize RF drive system control during energy recovery and FEL operation. The presentation will address the design process and design solution for an accelerator transport lattice that meets the requirements imposed by these physical phenomena and operational necessities.

  10. Locking Lasers to RF in an Ultrafast FEL

    International Nuclear Information System (INIS)

    Wilcox, R.; Huang, G.; Doolittle, L.; White, W.; Frisch, J.; Coffee, R.

    2010-01-01

    Using a novel, phase-stabilized RF-over-fiber scheme, they transmit 3GHz over 300m with 27fs RMS error in 250kHz bandwidth over 12 hours, and phase lock a laser to enable ultrafast pump-probe experiments. Free-electron lasers (FELs) are capable of producing short-duration (< 10fs), high-energy X-ray pulses for a range of scientific applications. The recently activated Linac Coherent Light Source (LCLS) FEL facility at SLAC will support experiments which require synchronized light pulses for pump-probe schemes. They developed and operated a fiber optic RF transmission system to synchronize lasers to the emitted X-ray pulses, which was used to enable the first pump-probe experiments at the LCLS.

  11. Status of the tandem FEL project development in Israel

    International Nuclear Information System (INIS)

    Benzvi, I.; Sokolowski, J.; Jerby, E.; Chomski, D.; Ruschin, S.

    1989-01-01

    The authors report the status of a collaborative research project development aimed toward construction of an IR FEL based on the EN tandem electrostatic accelerator of the Weizmann Institute of Science. A preliminary feasibility demonstration project yielded encouraging progress in three aspects: (1) Electron gun and accelerator conversion: A 50-kV 1-A electron gun injector was designed, built, tested, and assembled on the 6-MeV tandem accelerator which was previously converted and conditioned to operate as an electron accelerator in a positively charged HV terminal configuration. Contrary to the configuration of the only electrostatic accelerator FEL demonstrated so far, the electron gun and multistage depressed collector are connected to the ground, and the wiggler is placed in the HV terminal of the straight geometry tandem accelerator. This configuration promises to provide a high current high quality e-beam. (2) Electron-beam transport: The first installation of the electron optical beam recovery system yielded transport efficiency of 80%. Substantial improvement is expected with planned electron optics modifications. An effect, highly significant for realizing long pulse (quasi-cw) FEL operation, was observed experimentally. Due to the damping effect of the accelerator column capacitance network, the voltage terminal stayed constant for milliseconds even with poor beam transport efficiency. This points to the possibility of developing a long pulse FEL which may operate at a single longitudinal mode. (3) Wiggler development: A conventional 4.4-cm period SmCo planar wiggler was acquired and evaluated using a recently constructed floating wire magnetic field measurement setup

  12. The Harmonically Coupled 2-Beam FEL

    CERN Document Server

    McNeil, Brian W J

    2004-01-01

    A 1-D model of a 2-beam Free Electron Laser amplifier is presented. The two co-propagating electron beams have different energies, chosen so that the fundamental resonant FEL interaction of the higher energy beam is at an harmonic of the lower energy beam. In this way, a coupling between the FEL interactions of the two beams occurs via the harmonic components of the electron bunching and radiation emission of the lower energy interaction. Such resonantly coupled FEL interactions may offer potential benefits over existing single beam FEL schemes. A simple example is presented where the lower energy FEL interaction only is seeded with radiation at its fundamental resonant wavelength. It is predicted that the coherence properties of this seed field are transfered via the resonantly coupled FEL interaction to the un-seeded higher energy FEL interaction, thereby improving its coherence properties over that of a SASE interaction alone. This method may offer an alternative seeding scheme for FELs operating in the XU...

  13. Design considerations of a MW-scale, high-efficiency, industrial-use, ultraviolet FEL amplifier

    International Nuclear Information System (INIS)

    Pagani, C.; Saldin, E.L.; Schneidmiller, E.A.; Yurkov, M.V.

    2000-01-01

    Theoretical and experimental work in free electron laser (FEL) physics, and the physics of particle accelerators over the last 10 years has pointed to the possibility of the generation of MW-level optical beams with laser-like characteristics in the ultraviolet (UV) spectral range. The concept is based on generation of the radiation in the master oscillator-power FEL amplifier (MOPA) configuration. The FEL amplifier concept eliminates the need for an optical cavity. As a result, there are no thermal loading limitations to increase the average output power of this device up to the MW-level. The problem of a tunable master oscillator can be solved with available conventional quantum lasers. The use of a superconducting energy-recovery linac could produce a major, cost-effective facility with wall plug power to output optical power efficiency of about 20% that spans wavelengths from the visible to the deep ultraviolet regime. The stringent electron beam qualities required for UV FEL amplifier operation can be met with a conservative injector design (using a conventional thermionic gun and subharmonic bunchers) and the beam compression and linear acceleration technology, recently developed in connection with high-energy linear collider and X-ray FEL programs

  14. The GBTIA, a 5 Gbit/s Radiation-Hard Optical Receiver for the SLHC Upgrades

    CERN Document Server

    Menouni, M; Moreira, P

    2009-01-01

    The GigaBit Transceiver (GBT) is a high-speed optical transmission system currently under development for HEP applications. This system will implement bi-directional optical links to be used in the radiation environment of the Super LHC. The GigaBit Transimpedance Amplifier (GBTIA) is the front-end optical receiver of the GBT chip set. This paper presents the GBTIA, a 5 Gbit/s, fully differential, and highly sensitive optical receiver designed and implemented in a commercial 0.13 μm CMOS process. When connected to a PIN-diode, the GBTIA displays a sensitivity better than −19 dBm for a BER of 10−12. The differential output across an external 50 Ω load remains constant at 400 mVpp even for signals near the sensitivity limit. The chip achieves an overall transimpedance gain of 20 kΩ with a measured bandwidth of 4 GHz. The total power consumption of the chip is less than 120 mW and the chip die size is 0.75 mm x 1.25 mm. Irradiation testing of the chip shows no performance degradation after a dose rate of ...

  15. Electron bunch length measurement at the Vanderbilt FEL

    Energy Technology Data Exchange (ETDEWEB)

    Amirmadhi, F.; Brau, C.A.; Mendenhall, M. [Vanderbilt Free-Electron-Laser Center, Nashville, TN (United States)] [and others

    1995-12-31

    During the past few years, a number of experiments have been performed to demonstrate the possibility to extract the longitudinal charge distribution from spectroscopic measurements of the coherent far-infrared radiation emitted as transition radiation or synchrotron radiation. Coherent emission occurs in a spectral region where the wavelength is comparable to or longer than the bunch length, leading to an enhancement of the radiation intensity that is on the order of the number of particles per bunch, as compared to incoherent radiation. This technique is particularly useful in the region of mm and sub-mm bunch lengths, a range where streak-cameras cannot be used for beam diagnostics due to their limited time resolution. Here we report on experiments that go beyond the proof of principle of this technique by applying it to the study and optimization of FEL performance. We investigated the longitudinal bunch length of the Vanderbilt FEL by analyzing the spectrum of coherent transition radiation emitted by the electron bunches. By monitoring the bunch length while applying a bunch-compression technique, the amount of the compression could be easily observed. This enabled us to perform a systematic study of the FEL performance, especially gain and optical pulse width, as a function of the longitudinal electron distribution in the bunch. The results of this study will be presented and discussed.

  16. Mode distortion measurements on the Jefferson lab IR FEL

    CERN Document Server

    Benson, S V; Shinn, M

    2002-01-01

    We have previously reported on the analytical calculations of mirror distortion in a high-power FEL with a near-concentric cavity. This analysis allowed us to estimate the power level at which the FEL interaction would be affected, though no exact theory of FEL power vs. distortion exists at this point. Recently we have directly measured the mode size and beam quality as a function of power using a resonator with a center wavelength of 5 mu m. The resonator mirrors were calcium fluoride. This particular material exhibits a large amount of distortion for a given power but, due to the negative slope of refractive index vs. temperature, adds almost no optical phase distortion on the laser output. The mode in the cavity can thus be directly calculated from the measurements at the resonator output. The presence of angular jitter produced raw measurements inconsistent with cold cavity expectations. Removing the effects of the angular jitter, we derive results in agreement with cold cavity measurements. The result i...

  17. ETHERNET BASED EMBEDDED SYSTEM FOR FEL DIAGNOSTICS AND CONTROLS

    International Nuclear Information System (INIS)

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

    2006-01-01

    An Ethernet based embedded system has been developed to upgrade the Beam Viewer and Beam Position Monitor (BPM) systems within the free-electron laser (FEL) project at Jefferson Lab. The embedded microcontroller was mounted on the front-end I/O cards with software packages such as Experimental Physics and Industrial Control System (EPICS) and Real Time Executive for Multiprocessor System (RTEMS) running as an Input/Output Controller (IOC). By cross compiling with the EPICS, the RTEMS kernel, IOC device supports, and databases all of these can be downloaded into the microcontroller. The first version of the BPM electronics based on the embedded controller was built and is currently running in our FEL system. The new version of BPM that will use a Single Board IOC (SBIOC), which integrates with an Field Programming Gate Array (FPGA) and a ColdFire embedded microcontroller, is presently under development. The new system has the features of a low cost IOC, an open source real-time operating system, plug and play-like ease of installation and flexibility, and provides a much more localized solution

  18. Obtaining high degree of circular polarization at X-ray FELs via a reverse undulator taper

    Energy Technology Data Exchange (ETDEWEB)

    Schneidmiller, E.A.; Yurkov, M.V.

    2013-08-15

    Baseline design of a typical X-ray FEL undulator assumes a planar configuration which results in a linear polarization of the FEL radiation. However, many experiments at X-ray FEL user facilities would profit from using a circularly polarized radiation. As a cheap upgrade one can consider an installation of a short helical (or cross-planar) afterburner, but then one should have an efficient method to suppress powerful linearly polarized background from the main undulator. In this paper we propose a new method for such a suppression: an application of the reverse taper in the main undulator. We discover that in a certain range of the taper strength, the density modulation (bunching) at saturation is practically the same as in the case of non-tapered undulator while the power of linearly polarized radiation is suppressed by orders of magnitude. Then strongly modulated electron beam radiates at full power in the afterburner. Considering SASE3 undulator of the European XFEL as a practical example, we demonstrate that soft X-ray radiation pulses with peak power in excess of 100 GW and an ultimately high degree of circular polarization can be produced. The proposed method is rather universal, i.e. it can be used at SASE FELs and seeded (self-seeded) FELs, with any wavelength of interest, in a wide range of electron beam parameters, and with any repetition rate. It can be used at different X-ray FEL facilities, in particular at LCLS after installation of the helical afterburner in the near future.

  19. Design of a petawatt optical parametric chirped pulse amplification upgrade of the kilojoule iodine laser PALS

    Czech Academy of Sciences Publication Activity Database

    Novák, Ondřej; Divoký, Martin; Turčičová, Hana; Straka, Petr

    2013-01-01

    Roč. 31, č. 2 (2013), s. 211-218 ISSN 0263-0346 R&D Projects: GA ČR GA202/06/0814; GA MŠk(CZ) LC528; GA MŠk LN00A100 EU Projects: European Commission(XE) 506350 - LASERLAB-EUROPE Institutional support: RVO:68378271 Keywords : VULCAN petawatt * system * prospects * facility * program Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.701, year: 2013 http://journals.cambridge.org/action/displayAbstract?fromPage=online& aid =8950936

  20. Outline of optical design and viewing geometry for divertor Thomson scattering on MAST upgrade

    Czech Academy of Sciences Publication Activity Database

    Hawke, J.; Scannell, R.; Harrison, J.; Huxford, R.; Böhm, Petr

    2013-01-01

    Roč. 8, č. 11 (2013), C11010-C11010 ISSN 1748-0221. [International Symposium Laser Aided Plasma Diagnostics/16./. Madison, 22.09.2013-26.09.2013] Institutional support: RVO:61389021 Keywords : Plasma diagnostics - interferometry * Spectroscopy and imaging * Optics * Plasma diagnostics - charged-particle spectroscopy Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.526, year: 2013 http://iopscience.iop.org/1748-0221/8/11/C11010/pdf/1748-0221_8_11_C11010.pdf

  1. Tracking Performance of Upgraded "Polished Panel" Optical Receiver on NASA's 34 Meter Research Antenna

    Science.gov (United States)

    Vilnrotter, Victor

    2013-01-01

    There has been considerable interest in developing and demonstrating a hybrid "polished panel" optical receiver concept that would replace the microwave panels on the Deep Space Network's (DSN) 34 meter antennas with highly polished aluminum panels, thus enabling simultaneous opticaland microwave reception. A test setup has been installed on the 34 meter research antenna at DSS-13 (Deep Space Station 13) at NASA's Goldstone Deep Space Communications Complex in California in order to assess the feasibility of this concept. Here we describe the results of a recent effort todramatically reduce the dimensions of the point-spread function (PSF) generated by a custom polished panel, thus enabling improved optical communications performance. The latest results are compared to the previous configuration in terms of quantifiable PSF improvement. In addition, the performance of acquisition and tracking algorithms designed specifically for the polished panel PSF are evaluated and compared, based on data obtained from real-time tracking of planets and bright stars with the 34 meter research antenna at DSS-13.

  2. Design and optimization of the grating monochromator for soft X-ray self-seeding FELs

    Energy Technology Data Exchange (ETDEWEB)

    Serkez, Svitozar

    2015-10-15

    The emergence of Free Electron Lasers (FEL) as a fourth generation of light sources is a breakthrough. FELs operating in the X-ray range (XFEL) allow one to carry out completely new experiments that probably most of the natural sciences would benefit. Self-amplified spontaneous emission (SASE) is the baseline FEL operation mode: the radiation pulse starts as a spontaneous emission from the electron bunch and is being amplified during an FEL process until it reaches saturation. The SASE FEL radiation usually has poor properties in terms of a spectral bandwidth or, on the other side, longitudinal coherence. Self-seeding is a promising approach to narrow the SASE bandwidth of XFELs significantly in order to produce nearly transformlimited pulses. It is achieved by the radiation pulse monochromatization in the middle of an FEL amplification process. Following the successful demonstration of the self-seeding setup in the hard X-ray range at the LCLS, there is a need for a self-seeding extension into the soft X-ray range. Here a numerical method to simulate the soft X-ray self seeding (SXRSS) monochromator performance is presented. It allows one to perform start-to-end self-seeded FEL simulations along with (in our case) GENESIS simulation code. Based on this method, the performance of the LCLS self-seeded operation was simulated showing a good agreement with an experiment. Also the SXRSS monochromator design developed in SLAC was adapted for the SASE3 type undulator beamline at the European XFEL. The optical system was studied using Gaussian beam optics, wave optics propagation method and ray tracing to evaluate the performance of the monochromator itself. Wave optics analysis takes into account the actual beam wavefront of the radiation from the coherent FEL source, third order aberrations and height errors from each optical element. The monochromator design is based on a toroidal VLS grating working at a fixed incidence angle mounting without both entrance and exit

  3. Design and optimization of the grating monochromator for soft X-ray self-seeding FELs

    International Nuclear Information System (INIS)

    Serkez, Svitozar

    2015-10-01

    The emergence of Free Electron Lasers (FEL) as a fourth generation of light sources is a breakthrough. FELs operating in the X-ray range (XFEL) allow one to carry out completely new experiments that probably most of the natural sciences would benefit. Self-amplified spontaneous emission (SASE) is the baseline FEL operation mode: the radiation pulse starts as a spontaneous emission from the electron bunch and is being amplified during an FEL process until it reaches saturation. The SASE FEL radiation usually has poor properties in terms of a spectral bandwidth or, on the other side, longitudinal coherence. Self-seeding is a promising approach to narrow the SASE bandwidth of XFELs significantly in order to produce nearly transformlimited pulses. It is achieved by the radiation pulse monochromatization in the middle of an FEL amplification process. Following the successful demonstration of the self-seeding setup in the hard X-ray range at the LCLS, there is a need for a self-seeding extension into the soft X-ray range. Here a numerical method to simulate the soft X-ray self seeding (SXRSS) monochromator performance is presented. It allows one to perform start-to-end self-seeded FEL simulations along with (in our case) GENESIS simulation code. Based on this method, the performance of the LCLS self-seeded operation was simulated showing a good agreement with an experiment. Also the SXRSS monochromator design developed in SLAC was adapted for the SASE3 type undulator beamline at the European XFEL. The optical system was studied using Gaussian beam optics, wave optics propagation method and ray tracing to evaluate the performance of the monochromator itself. Wave optics analysis takes into account the actual beam wavefront of the radiation from the coherent FEL source, third order aberrations and height errors from each optical element. The monochromator design is based on a toroidal VLS grating working at a fixed incidence angle mounting without both entrance and exit

  4. JAERI FEL applications in nuclear energy industries

    International Nuclear Information System (INIS)

    Minehara, Eisuke J.

    2005-01-01

    The JAERI FEL has first discovered the new FEL lasing of 255fs ultra fast pulse, 6-9% high efficiency, 1GW high peak power, a few kilowatts average power, and wide tunability of medium and far infrared wavelength regions at the same time. Using the new lasing and energy-recovery linac technology, we could extend a more powerful and more efficient free-electron laser (FEL) than 10kW and 25%, respectively, for nuclear energy industries, and others. In order to realize such a tunable, highly-efficient, high average power, high peak power and ultra-short pulse FEL, we need the efficient and powerful FEL driven by the JAERI compact, stand alone and zero boil-off super-conducting RF linac with an energy-recovery geometry. Our discussions on the FEL will cover the application of non-thermal peeling, cutting, and drilling to prevent cold-worked stress-corrosion cracking failures in nuclear energy and other heavy industries. (author)

  5. Technological Challenges to X-Ray FELs

    Energy Technology Data Exchange (ETDEWEB)

    Nuhn, Heinz-Dieter

    1999-09-16

    There is strong interest in the development of x-ray free electron lasers (x-ray FELs). The interest is driven by the scientific opportunities provided by intense, coherent x-rays. An x-ray FEL has all the characteristics of a fourth-generation source: brightness several orders of magnitude greater than presently achieved in third-generation sources, full transverse coherence, and sub-picosecond long pulses. The SLAC and DESY laboratories have presented detailed design studies for X-Ray FEL user facilities around the 0.1 nm wavelength-regime (LCLS at SLAC, TESLA X-Ray FEL at DESY). Both laboratories are engaged in proof-of-principle experiments are longer wavelengths (TTF FEL Phase I at 71 nm, VISA at 600-800 nm) with results expected in 1999. The technologies needed to achieve the proposed performances are those of bright electron sources, of acceleration systems capable of preserving the brightness of the source, and of undulators capable of meeting the magnetic and mechanical tolerances that are required for operation in the SASE mode. This paper discusses the technological challenges presented by the X-Ray FEL projects.

  6. Design study of high gradient, low impedance accelerating structures for the FERMI free electron laser linac upgrade

    Science.gov (United States)

    Shafqat, N.; Di Mitri, S.; Serpico, C.; Nicastro, S.

    2017-09-01

    The FERMI free-electron laser (FEL) of Elettra Sincrotrone Trieste, Italy, is a user facility driven by a 1.5 GeV 10-50 Hz S-band radiofrequency linear accelerator (linac), and it is based on an external laser seeding scheme that allows lasing at the shortest fundamental wavelength of 4 nm. An increase of the beam energy to 1.8 GeV at a tolerable breakdown rate, and an improvement of the final beam quality is desired in order to allow either lasing at 4 nm with a higher flux, or lasing at shorter wavelengths. This article presents the impedance analysis of newly designed S-band accelerating structures, for replacement of the existing backward travelling wave structures (BTWS) in the last portion of the FERMI linac. The new structure design promises higher accelerating gradient and lower impedance than those of the existing BTWS. Particle tracking simulations show that, with the linac upgrade, the beam relative energy spread, its linear and nonlinear z-correlation internal to the bunch, and the beam transverse emittances can be made smaller than the ones in the present configuration, with expected advantage to the FEL performance. The repercussion of the upgrade on the linac quadrupole magnets setting, for a pre-determined electron beam optics, is also considered.

  7. A Cherenkov radiator for FEL-synchronized VUV-pulses at a linac-based FEL

    NARCIS (Netherlands)

    Goloviznin, V. V.; Oepts, D.; van der Wiel, M. J.

    1997-01-01

    A possible way to carry out two-color IR+VUV pump-probe experiments at linac-based FELs is proposed. The idea is to supply an FEL facility with a gas cell filled with helium or hydrogen, so that the electron beam, upon passage through the undulator, could be used to generate ultraviolet Cherenkov

  8. A Cherenkov radiator for FEL-synchronized VUV-pulses at a linac-based FEL

    NARCIS (Netherlands)

    Goloviznin, V.V.; Oepts, W.; Wiel, van der M.J.

    1997-01-01

    A possible way to carry out two-color IR + VUV pump-probe experiments at linac-based FELs is proposed. The idea is to supply an FEL facility with a gas cell filled with helium or hydrogen, so that the electron beam, upon passage through the undulator, could be used to generate ultraviolet Cherenkov

  9. Status report on the development of a high-power UV/IR FEL at CEBAF

    Energy Technology Data Exchange (ETDEWEB)

    Benson, S.; Bohn, C.; Dylla, H.F. [Continuous Electron Beam Accelerator Facility, Newport News, VA (United States)] [and others

    1995-12-31

    Last year we presented a design for a kilowatt industrial UV FEL based on a superconducting RF accelerator delivering 5 mA of electron-beam current at 200 MeV with energy recovery to enhance efficiency. Since then, we have progressed toward resolving several issues associated with that design. More exact simulations of the injector have resulted in a more accurate estimate of the injector performance. A new injection method has reduced the longitudinal and transverse emittance at the linac entrance. A more compact lattice has been designed for the UV FEL, and a new recirculation scheme has been identified which greatly increases the threshold for longitudinal instabilities. We decided to use a wiggler from the Advanced Photon Source which leads to a robust high-gain FEL. Analysis of the stability of an RF control system based on CEBAF control modules indicates that only minor modifications will be needed to apply them to this FEL. Detailed magnet specifications, vacuum-chamber beam apertures, and diagnostic specifications have been developed for the recirculation arcs. The design of the optical cavity has been conceptualized, and control systems have been devised to regulate mirror distortion. A half-scale model of one of the end-corner cubes has been built and tested. Finally, three-dimensional simulations have been carried out which indicate that the FEL should exceed its minimum design goals with adequate performance margin.

  10. Summary of the working group on FEL theory

    Energy Technology Data Exchange (ETDEWEB)

    Pellegrini, C.

    1984-01-01

    The working group on FEL theory dedicated most of its discussions to topics relevant to the high gain regime in a free electron laser. In addition the area of interest was mainly restricted to FELs for the production of XUV radiation (<1000 A). A list of the topics that were felt to be relevant is: (1) characterization of the FEL high gain regime; (2) the amplified spontaneous emission mode of operation (ASE); (3) superradiance in FELs; (4) diffraction effects for high gain FELs; (5) noise and start-up; (6) coherence properties of the radiation for the ASE and superradiant FELS. 9 references.

  11. Summary of the working group on FEL theory

    International Nuclear Information System (INIS)

    Pellegrini, C.

    1984-01-01

    The working group on FEL theory dedicated most of its discussions to topics relevant to the high gain regime in a free electron laser. In addition the area of interest was mainly restricted to FELs for the production of XUV radiation (<1000 A). A list of the topics that were felt to be relevant is: (1) characterization of the FEL high gain regime; (2) the amplified spontaneous emission mode of operation (ASE); (3) superradiance in FELs; (4) diffraction effects for high gain FELs; (5) noise and start-up; (6) coherence properties of the radiation for the ASE and superradiant FELS. 9 references

  12. Bunching phase evolution of short-pulse FEL oscillator system

    CERN Document Server

    Song, S B; Choi, D I

    2000-01-01

    We studied numerically the short-pulse FEL oscillator system using properly defined bunching phase theta sub B and PSI sub B. In stable operation, we have found that the optical field 'locks' the phase to pi/2 at the trailing edge, which gives the maximum gain. Moreover, electrons can be detrapped from ponderomotive bucket due to the spatial variation of the optical field, and this detrapping effect is a major cause of the limit cycle oscillation of the system. The 'bump' of the output power during the amplification usually exists at the near-perfect cavity synchronism regime, which can be explained as the change of the matching condition between electron micropulse and optical pulse.

  13. Coherent harmonic production using a two-section undulator FEL

    Energy Technology Data Exchange (ETDEWEB)

    Jaroszynski, D.A. [Commissariat a l`Energie, Bruyeres-le-Chatel (France); Prazeres, R.; Glotin, F. [Centre Universitaire Paris-Sud (France)] [and others

    1995-12-31

    We present measurements and a theoretical analysis of a new method of generating harmonic radiation in a free-electron laser oscillator with a two section undulator in a single optical cavity. To produce coherent harmonic radiation the undulator is arranged so that the downstream undulator section resonance frequency matches a harmonic of the upstream undulator. Both the fundamental and the harmonic optical fields evolve in the same optical cavity and are coupled out with different extraction fractions using a hole in one of the cavity mirrors. We present measurements that show that the optical power at the second and third harmonic can be enhanced by more than an order of magnitude in this fundamental/harmonic configuration. We compare the production of harmonic radiation of a two sectioned fundamental/harmonic undulator with that produced from a FEL operating at its highest efficiency with a step-tapered undulator, where the bunching at the end of the first section is very large. We examine, the dependence of the harmonic power on the intracavity power by adjusting the optical cavity desynchronism, {delta}L. We also examine the evolution of the fundamental and harmonic powers as a function of cavity roundtrip number to evaluate the importance of the small signal gain at the harmonic. We compare our measurements with predictions of a multi-electron numerical model that follows the evolution of fundamental and harmonic power to saturation. This fundamental/harmonic mode, of operation of the FEL may have useful applications in the production of coherent X-ray and VUV radiation, a spectral range where high reflectivity optical cavity mirrors are difficult or impossible to manufacture.

  14. Diode readout electronics for beam intensity and position monitors for FELs

    International Nuclear Information System (INIS)

    Herrmann, S; Hart, P; Freytag, M; Pines, J; Weaver, M; Sapozhnikov, L; Nelson, S; Koglin, J; Carini, G A; Tomada, A; Haller, G

    2014-01-01

    LCLS uses Intensity-Position Monitors (IPM) to measure intensity and position of the FEL x-ray pulses. The primary beam passes through a silicon nitride film and four diodes, arranged in quadrants, detect the backscattered x-ray photons. The position is derived from the relative intensity of the four diodes, while the sum provides beam intensity information. In contrast to traditional synchrotron beam monitors, where diodes measure a DC current signal, the LCLS beam monitors have to cope with the pulsed nature of the FEL, which requires a large single shot dynamic range. A key component of these beam monitors is the readout electronics. The first generation of beam monitors showed some limitations. A new scheme with upgraded electronics, firmware and software was implemented resulting in a more robust and reliable measuring tool.

  15. JAERI 10kW High Power ERL-FEL and Its Applications in Nuclear Energy Industries

    CERN Document Server

    Minehara, E J; Iijima, H; Kikuzawa, N; Nagai, R; Nishimori, N; Nishitani, T; Sawamura, M; Yamauchi, T

    2005-01-01

    The JAERI high power ERL-FEL has been extended to the more powerful and efficient free-electron laser (FEL) than 10kW for nuclear energy industries, and other heavy industries like defense, shipbuilding, chemical industries, environmental sciences, space-debris, and power beaming and so on. In order to realize such a tunable, highly-efficient, high average power, high peak power and ultra-short pulse FEL, we need the efficient and powerful FEL driven by the JAERI compact, stand-alone and zero boil-off super-conducting RF linac with an energy-recovery geometry. Our discussions on the ERL-FEL will cover the current status of the 10kW upgrading and its applications of non-thermal peeling, cutting, and drilling to decommission the nuclear power plants, and to demonstrate successfully the proof of principle prevention of cold-worked stress-corrosion cracking failures in nuclear power reactors under routine operation using small cubic low-Carbon stainless steel samples.

  16. The FERMI-Elettra FEL Photon Transport System

    International Nuclear Information System (INIS)

    Zangrando, M.; Cudin, I.; Fava, C.; Godnig, R.; Kiskinova, M.; Masciovecchio, C.; Parmigiani, F.; Rumiz, L.; Svetina, C.; Turchet, A.; Cocco, D.

    2010-01-01

    The FERMI-Elettra free electron laser (FEL) user facility is under construction at Sincrotrone Trieste (Italy), and it will be operative in late 2010. It is based on a seeded scheme providing an almost perfect transform-limited and fully spatially coherent photon beam. FERMI-Elettra will cover the wavelength range 100 to 3 nm with the fundamental harmonics, and down to 1 nm with higher harmonics. We present the layout of the photon beam transport system that includes: the first common part providing on-line and shot-to-shot beam diagnostics, called PADReS (Photon Analysis Delivery and Reduction System), and 3 independent beamlines feeding the experimental stations. Particular emphasis is given to the solutions adopted to preserve the wavefront, and to avoid damage on the different optical elements. Peculiar FEL devices, not common in the Synchrotron Radiation facilities, are described in more detail, e.g. the online photon energy spectrometer measuring shot-by-shot the spectrum of the emitted radiation, the beam splitting and delay line system dedicated to cross/auto correlation and pump-probe experiments, and the wavefront preserving active optics adapting the shape and size of the focused spot to meet the needs of the different experiments.

  17. Los Alamos High-Brightness Accelerator FEL (HIBAF) facility

    Energy Technology Data Exchange (ETDEWEB)

    Cornelius, W.D.; Bender, S.; Meier, K.; Thode, L.E.; Watson, J.M.

    1989-01-01

    The 10-/mu/m Los Alamos free-electron laser (FEL) facility is being upgraded. The conventional electron gun and bunchers have been replaced with a much more compact 6-MeV photoinjector accelerator. By adding existing parts from previous experiments, the primary beam energy will be doubled to 40 MeV. With the existing 1-m wiggler (/lambda//sub w/ = 2.7 cm) and resonator, the facility can produce photons with wavelengths from 3 to 100 /mu/m when lasing on the fundamental mode and produce photons in the visible spectrum with short-period wigglers or harmonic operation. After installation of a 150/degree/ bend, a second wiggler will be added as an amplifier. The installation of laser transport tubes between the accelerator vault and an upstairs laboratory will provide experimenters with a radiation-free environment for experiments. Although the initial experimental program of the upgraded facility will be to test the single accelerator-master oscillator/power amplifier configuration, some portion of the operational time of the facility can be dedicated to user experiments. 13 refs., 5 figs., 6 tabs.

  18. Design study of a longer wavelength FEL for FELIX

    International Nuclear Information System (INIS)

    Lin, L.; Oepts, D.; Meer, A.F.G. van der

    1995-01-01

    We present a design study of FEL3, which will extend the FELIX spectral range towards a few hundred microns. A rectangular waveguide will be used to reduce diffraction losses. Calculations show that with a waveguide gap of 1 cm, only one sinusoidal mode along the guided direction can exist within the FEL gain bandwidth, thus excluding group velocity dispersion and lengthening of short radiation pulses. To incorporate FEL3 in the existing FELIX facility, two options are being considered: to combine FEL3 with FEL1 by insertion of a waveguide into FEL1, and to build a dedicated third beam line for FEL3 after the two linacs. Expected FEL performance: gain, spectrum, power, pulse shape, etc., will be presented based on numerical simulations

  19. Multi-mode interactions in an FEL oscillator

    CERN Document Server

    Dong Zhi Wei; Masuda, K; Yamazaki, T; Yoshikawa, K

    2000-01-01

    A 3D time-dependent FEL oscillator simulation code has been developed by using the transverse mode spectral method to analyze interaction among transverse modes. The competition among them in an FEL oscillator was investigated based on the parameters of LANL FEL experiments. It is found that under typical FEL oscillator operation conditions, the TEM sub 0 sub 0 mode is dominant, and the effects of other transverse modes can be negligible.

  20. The APS SASE FEL: modeling and code comparison

    International Nuclear Information System (INIS)

    Biedron, S. G.

    1999-01-01

    A self-amplified spontaneous emission (SASE) free-electron laser (FEL) is under construction at the Advanced Photon Source (APS). Five FEL simulation codes were used in the design phase: GENESIS, GINGER, MEDUSA, RON, and TDA3D. Initial comparisons between each of these independent formulations show good agreement for the parameters of the APS SASE FEL

  1. Harmonic lasing in X-ray FELs

    Energy Technology Data Exchange (ETDEWEB)

    Schneidmiller, E.A.; Yurkov, M.V.

    2012-05-15

    Harmonic lasing in a free electron laser with a planar undulator (under the condition that the fundamental frequency is suppressed) might be a cheap and efficient way of extension of wavelength ranges of existing and planned X-ray FEL facilities. Contrary to nonlinear harmonic generation, harmonic lasing can provide much more intense, stable, and narrow-band FEL beam which is easier to handle due to the suppressed fundamental frequency. In this paper we perform a parametrization of the solution of the eigenvalue equation for lasing at odd harmonics, and present an explicit expression for FEL gain length, taking into account all essential effects. We propose and discuss methods for suppression of the fundamental harmonic. We also suggest a combined use of harmonic lasing and lasing at the retuned fundamental wavelength in order to reduce bandwidth and to increase brilliance of X-ray beam at saturation. Considering 3rd harmonic lasing as a practical example, we come to the conclusion that it is much more robust than usually thought, and can be widely used in the existing or planned X-ray FEL facilities. In particular, LCLS after a minor modification can lase to saturation at the 3rd harmonic up to the photon energy of 25-30 keV providing multi-gigawatt power level and narrow bandwidth. As for the European XFEL, harmonic lasing would allow to extend operating range (ultimately up to 100 keV), to reduce FEL bandwidth and to increase brilliance, to enable two-color operation for pump-probe experiments, and to provide more flexible operation at different electron energies. Similar improvements can be realized in other X-ray FEL facilities with gap-tunable undulators like FLASH II, SACLA, LCLS II, etc. Harmonic lasing can be an attractive option for compact X-ray FELs (driven by electron beams with a relatively low energy), allowing the use of the standard undulator technology instead of small-gap in-vacuum devices. Finally, in this paper we discover that in a part of the

  2. Optical modeling of induction-linac driven free-electron lasers

    International Nuclear Information System (INIS)

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

    1986-01-01

    The free-electron laser (FEL) simulation code FRED, developed at Lawrence Livermore National Laboratory (LLNL) primarily to model single-pass FEL amplifiers driven by induction linear accelerators, is described. The main emphasis is on the modeling of optical propagation in the laser and on the differences between the requirements for modeling rf-linac-driven vs. induction-linac-driven FELs. Examples of optical guiding and mode cleanup are presented for a 50 μm FEL

  3. Development of BPM Electronics at the JLAB FEL

    Science.gov (United States)

    Sexton, D.; Evtushenko, P.; Jordan, K.; Yan, J.; Dutton, S.; Moore, W.; Evans, R.; Coleman, J.

    2006-11-01

    A new version of BPM electronics based on the AD8362 RMS detector, which is a direct RF to DC converter, is under development at the JLAB FEL. Each of these new BPM electronics utilizes an embedded ColdFire Microprocessor for data processing and communication with the EPICS control system via TCP/IP. The ColdFire runs RTEMS, which is an open source real-time operating system. The JLAB FEL is a SRF Energy Recovery LINAC capable of running up to 10 mA CW beam with a 74.85 MHz micropulse frequency. For diagnostic reasons and for machine tune up, the micropulse frequency can be reduced to 1.17 MHz, which corresponds to about 160 μA of beam current. It is required that the BPM system would be functional for all micropulse frequencies. By taking into account the headroom for the beam steering and current variations the dynamic range of the RF front end is required to be about 60 dB. A BPM resolution of at least 100 μm is required, whereas better resolution is very desirable to make it possible for more accurate measurements of the electron beam optics. Some results of the RF front end development are presented as well as the first measurements made with an electron beam.

  4. A Mode Locked UV-FEL

    CERN Document Server

    Parvin, Parviz

    2004-01-01

    An appropriate resonator has been designed to generate femtosecond mode locked pulses in a UV FEL with the modulator performance based on the gain switching. The gain broadening due to electron energy spread affects on the gain parameters, small signal gain (γ0) and saturation intensity (Is), to determine the optimum output coupling as small.

  5. The CSU Accelerator and FEL Facility

    NARCIS (Netherlands)

    Milton, S.V.; Biedron, S.G.; Burleson, T.; Carrico, C.; Edelenbos, J.; Hall, C.; Horovitz, K.; Morin, A.; Rand, L.; Sipahi, N.; Sipahi, T.; van der Slot, P.; Yehudah, H.; Dong, A.; Tanaka, T.; Schaa, V.R.W.

    2013-01-01

    The Colorado State University (CSU) Accelerator Facility will include a 6-MeV L-Band electron linear accelerator (linac) with a free-electron laser (FEL) system capable of producing Terahertz (THz) radiation, a laser laboratory, a microwave test stand, and a magnetic test stand. The photocathode

  6. FEL based photon collider of TeV energy range

    International Nuclear Information System (INIS)

    Saldin, E.L.; Shnejdmiller, E.A.; Sarantsev, V.P.; Yurkov, M.V.

    1994-01-01

    Physical principles of operation of high energy photon linear colliders (PLC) based on the Compton backscattering of laser photons on high energy electrons are discussed. The main emphasis is put on the analysis of a possibility to construct the PLC with the center of mass energy 0.5-2 TeV. Free electron laser (FEL) is considered as a source of primary photons. Proposed FEL system consists of a tunable FEL oscillator (output power ∼ 1 - 10 MW) with subsequent amplification of the master signal in a FEL amplifier up to the power ∼ 3 x 10 11 W. The FEL parameters are optimized, restrictions on the electron beam and FEL magnetic system parameters are formulated and problems of technical realization are discussed. It is shown that the FEL technique provides the most suitable way to construct photon linear collider on the base of future generation linear collider. 22 refs., 10 figs., 2 tabs

  7. FEL radiation power available in electron storage rings

    International Nuclear Information System (INIS)

    Miyahara, Yoshikazu

    1994-01-01

    FEL radiation power available in electron storage rings was studied in the small signal regime in considering the increase of the energy spread of the electron beam caused by the FEL interaction and the decrease of the FEL gain with the increase of the energy spread in addition to the radiation damping and the quantum excitation. All these effects were considered separately, and combined with FEL power equations. The radiation power available was expressed explicitly with the parameters of the storage ring, the wiggler and the mirrors. The transient process of FEL lasing is simulated with the power equations. A rough estimation is made of the radiation power available by the FEL at different beam energies, and optimization of FEL parameters for a higher radiation power is discussed. ((orig.))

  8. SwissFEL - Conceptual design report

    International Nuclear Information System (INIS)

    Ganter, R.

    2010-07-01

    This report issued by the Paul Scherrer Institute (PSI) in Switzerland takes a look at the design concepts behind the institute's SwissFEL X-ray Laser facility. The goal of SwissFEL is to provide a source of extremely bright and short X-ray pulses enabling scientific discoveries in a wide range of disciplines to be made, from fundamental research through to applied science. The eminent scientific need for such an X-ray source which is well documented in the SwissFEL Science Case Report is noted. The technical design of SwissFEL has to keep a delicate balance between the demand by experimentalists for breathtaking performance in terms of photon beam properties on the one hand, and essential requirements for a user facility, such as confidence in technical feasibility, reliable and stable functioning and economy of installation and operation on the other hand. The baseline design which has been defined is discussed. This relies entirely on state-of-the-art technologies without fundamental feasibility issues. This SwissFEL Conceptual Design Report describes the technical concepts and parameters used for this baseline design. The report discusses the design strategy, the choice of parameters and the simulation of the accelerator unit and undulator. The photon beam layout is discussed, as is the installation's tera hertz pump source. The components of the facility, including the laser and radio-frequency systems, timing and synchronisation systems, magnets, undulators, and mechanical support systems are discussed. Further, the concepts behind electron beam diagnostics, vacuum equipment as well as control and feedback systems are discussed. The building layout is described and safety issues are discussed. An appendix completes the report

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

    CERN Document Server

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

    2004-01-01

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

  10. A 300-nm compact mm-wave linac FEL design

    Energy Technology Data Exchange (ETDEWEB)

    Nassiri, A.; Kustom, R.L.; Kang, Y.W. [Argonne National Lab., IL (United States)

    1995-12-31

    Microfabrication technology offers an alternative method for fabricating precision, miniature-size components suitable for use in accelerator physics and commercial applications. The original R&D work at Argonne, in collaboration with the University of Illinois at Chicago, has produced encouraging results in the area of rf accelerating structure design, optical and x-ray masks production, deep x-ray lithography (LIGA exposures), and precision structural alignments. In this paper we will present a design study for a compact single pass mm-linac FEL to produce short wavelength radiation. This system will consists of a photocathode rf gun operated at 30 GHz, a 50-MeV superconducting constant gradient structure operated at 60 GHz, and a microundulator with 1-mm period. Initial experimental results on a scale model rf gun and microundulator will be presented.

  11. Direct experimental observation of the gas density depression effect using a two-bunch X-ray FEL beam.

    Science.gov (United States)

    Feng, Y; Schafer, D W; Song, S; Sun, Y; Zhu, D; Krzywinski, J; Robert, A; Wu, J; Decker, F J

    2018-01-01

    The experimental observation of the depression effect in gas devices designed for X-ray free-electron lasers (FELs) is reported. The measurements were carried out at the Linac Coherent Light Source using a two-bunch FEL beam at 6.5 keV with 122.5 ns separation passing through an argon gas cell. The relative intensities of the two pulses of the two-bunch beam were measured, after and before the gas cell, from X-ray scattering off thin targets by using fast diodes with sufficient temporal resolution. At a cell pressure of 140 hPa, it was found that the after-to-before ratio of the intensities of the second pulse was about 17% ± 6% higher than that of the first pulse, revealing lower effective attenuation of the gas cell due to heating by the first pulse and subsequent gas density reduction in the beam path. This measurement is important in guiding the design and/or mitigating the adverse effects in gas devices for high-repetition-rate FELs such as the LCLS-II and the European XFEL or other future high-repetition-rate upgrades to existing FEL facilities.

  12. Nonlinear absorption and transmission properties of Ge, Te and InAs using tuneable IR FEL

    Energy Technology Data Exchange (ETDEWEB)

    Amirmadhi, F.; Becker, K.; Brau, C.A. [Vanderbilt Univ., Nashville, TN (United States)

    1995-12-31

    Nonlinear absorption properties of Ge, Te and InAs are being investigated using the transmission of FEL optical pulses through these semiconductors (z-scan method). Wavelength, intensity and macropulse dependence are used to differentiate between two-photon and free-carrier absorption properties of these materials. Macropulse dependence is resolved by using a Pockles Cell to chop the 4-{mu}s macropulse down to 100 ns. Results of these experiments will be presented and discussed.

  13. FEL system with homogeneous average output

    Energy Technology Data Exchange (ETDEWEB)

    Douglas, David R.; Legg, Robert; Whitney, R. Roy; Neil, George; Powers, Thomas Joseph

    2018-01-16

    A method of varying the output of a free electron laser (FEL) on very short time scales to produce a slightly broader, but smooth, time-averaged wavelength spectrum. The method includes injecting into an accelerator a sequence of bunch trains at phase offsets from crest. Accelerating the particles to full energy to result in distinct and independently controlled, by the choice of phase offset, phase-energy correlations or chirps on each bunch train. The earlier trains will be more strongly chirped, the later trains less chirped. For an energy recovered linac (ERL), the beam may be recirculated using a transport system with linear and nonlinear momentum compactions M.sub.56, which are selected to compress all three bunch trains at the FEL with higher order terms managed.

  14. Harmonic Content of the BESSY FEL Radiation

    CERN Document Server

    Meseck, Atoosa

    2005-01-01

    BESSY proposes a linac-based cascaded High-Gain Harmonic-Generation (HGHG) free electron laser (FEL) multi-user facility. The BESSY soft X-ray FEL will consist of three undulator lines. The associated tunable lasers will cover the spectral range of 230nm to 460nm. Two to four HGHG stages reduce the seed wavelength to the desired radiation range of 1.24nm < λ < 51nm. The harmonic content of the high-intensity radiator output can be used to reduce the number of necessary HGHG stages. Moreover the higher harmonic content of the final output extends the offered spectral range and thus is of high interest for the user community. In this paper, the higher harmonic content of the final output as well as of the output of several radiators are investigated. The main parameters such as output power, pulse duration and bandwidth as well as their suitability for seeding are discussed.

  15. Growth of transverse coherence in SASE FELs

    International Nuclear Information System (INIS)

    Kumar, Vinit; Krishnagopal, Srinivas

    2000-01-01

    We introduce the correlation function between the electric field at two different points in the transverse plane as a parameter to quantify the degree of transverse coherence. We also propose a more realistic model for the initialization of the radiation in computer codes used to study SASE FELs. We make these modifications in the code TDA and use it to study the growth of transverse coherence as a function of electron beam size, beam current and transverse emittance. Our results show explicitly that the onset of full transverse coherence in SASE takes place much before the power saturates. With the more realistic model the onset of the exponential growth regime is delayed, and to get a given power from the FEL one needs a longer undulator than would be predicted by the original TDA code

  16. Establishment of a laboratory for spectroscopic investigation of radioactive samples at the ELBE-FEL facility. Intentions and perspectives

    International Nuclear Information System (INIS)

    Foerstendorf, H.; Friedrich, H.; Heise, K.H.

    2002-01-01

    The Institute of Radiochemistry is setting up a radionuclide laboratory for optical spectroscopy at the free electron laser facility of the ELBE electron accelerator (ELBE-FEL). The quality of the infrared light source opens up new fields of analytical research in radiochemistry. Some aspects of future applications are introduced. (orig.)

  17. Spontaneous emission in Cherenkov FEL devices

    International Nuclear Information System (INIS)

    Ciocci, F.; Dattoli, G.; Doria, A.; Schettini, G.; Torre, A.; Walsh, J.E.

    1987-01-01

    The main features of the spectral characteristics of the spontaneously emitted Cherenkov light in circular and rectangular wave-guides filled with dielectric are discussed. The characteristics of the radiation emitted by an electron beam moving near and parallel to the surface of a dielectric slab are also analysed. Finally, the relevance of these results to a possible FEL-Cherenkov operation is briefly discussed

  18. Duke storage rink UV/VUV FEL: Status and prospects

    Energy Technology Data Exchange (ETDEWEB)

    Litvinenko, V.N.; Burnham, B.; Madey, J.M.J. [Duke Univ., Durham, NC (United States)] [and others

    1995-12-31

    The 1 GeV Duke storage ring was successfully commissioned with parameters exceeding initial specification. The OK-4 FEL has arrived at the Duke FEL laboratory from the Novosibirsk Institute of Nuclear Physics. The OK-4 installation and commissioning is in progress. In this paper we describe the up-to-date status of the Duke storage ring and the OK-4 FEL. The projected performance of the OK-4 UV/VUV FEL is presented based on the electron beam parameters achieved. Initial plans to operate the OK-4 UV/VUV FEL at the Duke 1 GeV storage ring are outlined. Future plans and prospects of both the OK-4 FEL and the Duke storage ring are discussed.

  19. Quantum SASE FEL with a Laser Wiggler

    CERN Document Server

    Bonifacio, R

    2005-01-01

    Quantum effects in high-gain FELs become relevant when ρ'=ρ(mcγ/ ћ k)<1. The quantum FEL parameter ρ' rules the maximum number of photons emitted per electrons. It has been shown that when ρ'<1 a "quantum purification" of the SASE regime occurs: in fact, the spectrum of the emitted radiation (randomly spiky in the usual classical SASE regime) shrinks to a very narrow single line, leading to a high degree of temporal coherence. From the definition of ρ it appears that in order to achieve the quantum regime, small values of ρ, beam energy and radiation wavelength are necessary. These requirements can be met only using a laser wiggler. In this work we state the scaling laws necessary to operate a SASE FEL in the Angstrom region. All physical quantities are expressed in terms of the normalized emittance and of two parameters: the ratio between laser and electron beam spot sizes and the ratio between Rayleigh range and electron ...

  20. FEL Trajectory Analysis for the VISA Experiment

    International Nuclear Information System (INIS)

    Nuhn, Heinz-Dieter

    1998-01-01

    The Visual to Infrared SASE Amplifier (VISA) [1] FEL is designed to achieve saturation at radiation wavelengths between 800 and 600 nm with a 4-m pure permanent magnet undulator. The undulator comprises four 99-cm segments each of which has four FODO focusing cells superposed on the beam by means of permanent magnets in the gap alongside the beam. Each segment will also have two beam position monitors and two sets of x-y dipole correctors. The trajectory walk-off in each segment will be reduced to a value smaller than the rms beam radius by means of magnet sorting, precise fabrication, and post-fabrication shimming and trim magnets. However, this leaves possible inter-segment alignment errors. A trajectory analysis code has been used in combination with the FRED3D [2] FEL code to simulate the effect of the shimming procedure and segment alignment errors on the electron beam trajectory and to determine the sensitivity of the FEL gain process to trajectory errors. The paper describes the technique used to establish tolerances for the segment alignment

  1. Renewal of KU-FEL Facility

    CERN Document Server

    Kii, Toshiteru; Masuda, Kai; Murakami, Shio; Ohgaki, Hideaki; Yamazaki, Tetsuo; Yoshikawa, Kiyoshi; Zen, Heishun

    2004-01-01

    Users demands to a high power tunable IR laser are increasing in Japan in energy-related science, such as basic study of high-efficiency solar cells, generation of new energy source of alcohol and/or H2 from polluted gas, and separation of DNA and/or RNA. To satisfy these demands, we decided to renew our FEL facility more user friendly and to operate more flexibly. Construction and fundamental studies on the KU-FEL have been carried out at a building of Institute of Chemical Research where few other accelerators are operating. Therefore, available machine time for our experiments is quite limited. We are now modifying the room by adding concrete walls of 2-m thickness and some space for users will be available. The present FEL system will be moved to the room A photocathode RF-gun system will be nearly added to the system and the present thermionic RF-gun will be used ternatively according to the demands of users. The photocathode material will be Cs2Te. The room with the shielding will be completed in June, ...

  2. Bunch compression for an FEL at NLCTA

    International Nuclear Information System (INIS)

    Zimmermann, F.

    1997-04-01

    As part of the design effort for a free electron laser driven by the Next Linear Collider Test Accelerator (NLCTA), the author reports studies of bunch-length compression utilizing the existing infrastructure and hardware. In one possible version of the NLCTA FEL, bunches with 900-microm FWHM length, generated by an S-band photo-injector, would be compressed to an rms length of 60--120 microm before entering the FEL undulator. It is shown that, using the present magnetic chicane, the bunch compression is essentially straightforward, and that almost all emittance-diluting effects, e.g. wakefields, chromaticity, or space charge in the bending magnets, are small. The only exception to this finding is the predicted increase of the horizontal emittance due to coherent synchrotron radiation (CSR). Estimates based on existing theories of coherent synchrotron radiation suggest a tripling or quadrupling of the initial emittance, which seems to preclude bunch compression during regular FEL operation. Serendipitously, the magnitude of the predicted emittance growth would, on the other hand, make the NLCTA chicane an excellent tool for measuring the effects of coherent synchrotron radiation. This will be of considerable interest to many future projects, in particular to the Linac Coherent Light Source (LCLS). As an aside, it is shown that coherent synchrotron radiation in a bending magnet gives rise to a minimum possible bunch length, which is very reminiscent of the Oide limit on the vertical spot size at the interaction point of a linear collider

  3. FEL for the polymer processing industries

    Science.gov (United States)

    Kelley, Michael J.

    1997-05-01

    Polymers are everywhere in modern life because of their unique combination of end-use functionalities, ease of processing, recycling potential and modest cost. The physical and economic scope of the infrastructure committed to present polymers makes the introduction of entirely new chemistry unlikely. Rather, the breadth of commercial offerings more likely to shrink in the face of the widening mandate for recycling, especially of packaging. Improved performance and new functionality must therefore come by routes such as surface modification. However they must come with little environmental impact and at painfully low cost. Processing with strongly absorbed light offers unique advantages. The journal and patent literatures disclose a number of examples of benefits that can be achieved, principally by use of excimer lasers or special UV lamps. Examples of commercialization are few, however, because of the unit cost and maximum scale of existing light sources. A FEL, however, offers unique advantages: tunability to the optimum wavelength, potential for scale up to high average power, and a path to attractively low unit cost of light. A business analysis of prospective applications defines the technical and economic requirements a FEL for polymer surface processing must meet. These are compared to FEL technology as it now stands and as it is envisioned.

  4. First lasings at IR-and FIR range using hybrid type undulator (FEL facility 4) and Halbach type undulator

    International Nuclear Information System (INIS)

    Takii, T.; Oshita, E.; Okuma, S.; Wakita, K.; Koga, A.; Tomimasu, T.; Ohasi, K.

    1997-01-01

    First lasing at 18μm was achieved by using a 2.7-m long hybrid type undulator (undulator 4) for far-infrared FELs and a 6.72-m long optical cavity installed at the 33-MeV beam line of the downstream of the FEL facility 1 (FEL-1). We are challenged at two-color FEL oscillation in mid-infrared range using the undulator 1 (λ u=3.4mm) and in far-infrared range using the undulator 4 (λ u=9mm). At first, a 30-MeV, 60-A beam passed through the undulator 1 without lasing is transported using a QFQDBQFQDBQFQDQF system and is used for lasing at the undulator 4. However, six pairs of steering coils had to be attached on the beam duct to reduce the deviation of the electron beam trajectory due to the vertical field distribution induced by the built-in electromagnets. The minimum gap of the undulator 4 was designed to be 35mm. However, the steering coils attached on the beam duct increased the gap up to 52mm. Therefore, the hybrid type undulator was replaced by a new Halbach type one (λ u=8mm, N=30) after the first lasing at 18μm on October 24, '96. The New FEL facility 4 was installed in the middle of December and first lasing at 18.6μm was achieved on December 26, within 10 hours operation. (author)

  5. SwissFEL injector conceptual design report. Accelerator test facility for SwissFEL

    International Nuclear Information System (INIS)

    Pedrozzi, M.

    2010-07-01

    This comprehensive report issued by the Paul Scherrer Institute (PSI) in Switzerland takes a look at the design concepts behind the institute's SwissFEL X-ray Laser facility - in particular concerning the conceptual design of the injector system. The SwissFEL X-ray FEL project at PSI, involves the development of an injector complex that enables operation of a FEL system operating at 0.1 - 7 nm with permanent-magnet undulator technology and minimum beam energy. The injector pre-project was motivated by the challenging electron beam requirements necessary to drive the SwissFEL accelerator facility. The report takes a look at the mission of the test facility and its performance goals. The accelerator layout and the electron source are described, as are the low-level radio-frequency power systems and the synchronisation concept. The general strategy for beam diagnostics is introduced. Low energy electron beam diagnostics, the linear accelerator (Linac) and bunch compressor diagnostics are discussed, as are high-energy electron beam diagnostics. Wavelength selection for the laser system and UV pulse shaping are discussed. The laser room for the SwissFEL Injector and constructional concepts such as the girder system and alignment concepts involved are looked at. A further chapter deals with beam dynamics, simulated performance and injector optimisation. The facility's commissioning and operation program is examined, as are operating regimes, software applications and data storage. The control system structure and architecture is discussed and special subsystems are described. Radiation safety, protection systems and shielding calculations are presented and the lateral shielding of the silo roof examined

  6. Start-Up of FEL Oscillator from Shot Noise

    International Nuclear Information System (INIS)

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

    2007-01-01

    In free-electron laser (FEL) oscillators, as in self-amplified spontaneous emission (SASE) FELs, the buildup of cavity power starts from shot noise resulting from the discreteness of electronic charge. It is important to do the start-up analysis for the build-up of cavity power in order to fix the macropulse width from the electron accelerator such that the system reaches saturation. In this paper, we use the time-dependent simulation code GINGER [1]to perform this analysis. We present results of this analysis for the parameters of the Compact Ultrafast TErahertz FEL (CUTE-FEL) [2] being built at RRCAT

  7. FEL small signal dynamics and electron beam prebunching

    International Nuclear Information System (INIS)

    Dattoli, G.

    1993-01-01

    A seed signal and/or a pre-bunched electron beam may provide the start up of a free electron laser (FEL). Recently, interest has grown around FEL's operating with pre-bunched electron beams; this paper is, therefore, devoted to the analysis of the dynamic features of FEL's operating in such a configuration. It exploits a slightly modified form of the FEL high gain equation to derive quantities of practical interest like the dependence of the system growth rate on the bunching coefficients

  8. Benefits from the BESSY FEL Higher Harmonic Radiation

    CERN Document Server

    Goldammer, K

    2005-01-01

    In the FEL process, bunching and coherent radiation is produced at the fundamental frequency as well as its higher harmonics. BESSY proposes a linac-based cascaded High-Gain Harmonic-Generation (HGHG) free electron laser (FEL) multi-user facility. The BESSY soft X-ray FEL will be seeded by three lasers spanning the spectral range of 230nm to 460nm. Two to four HGHG stages downconvert the seed wavelength to the desired radiation range of 1.24nm to 51nm using higher harmonic bunching. As a surplus, higher harmonic radiation is intrinsically produced in each FEL stage. Radiation on a higher harmonic of the FEL frequency is of high interest because it yields the possibility to reduce the number of FEL stages. This paper details extensive studies of the higher harmonic content of the BESSY FEL radiation. Important aspects of FEL interaction on higher harmonics as resulting from theory and from numerical simulations are discussed. For the case of the BESSY FEL, methods for improving the harmonic content are present...

  9. Nonlinear harmonic generation and proposed experimental verification in SASE FELs

    CERN Document Server

    Freund, H P; Milton, S V

    2000-01-01

    Recently, a 3D, polychromatic, nonlinear simulation code was developed to study the growth of nonlinear harmonics in self-amplified spontaneous emission (SASE) free-electron lasers (FELs). The simulation was applied to the parameters for each stage of the Advanced Photon Source (APS) SASE FEL, intended for operation in the visible, UV, and short UV wavelength regimes, respectively, to study the presence of nonlinear harmonic generation. Significant nonlinear harmonic growth is seen. Here, a discussion of the code development, the APS SASE FEL, the simulations and results, and, finally, the proposed experimental procedure for verification of such nonlinear harmonic generation at the APS SASE FEL will be given.

  10. Computer modelling of statistical properties of SASE FEL radiation

    International Nuclear Information System (INIS)

    Saldin, E. L.; Schneidmiller, E. A.; Yurkov, M. V.

    1997-01-01

    The paper describes an approach to computer modelling of statistical properties of the radiation from self amplified spontaneous emission free electron laser (SASE FEL). The present approach allows one to calculate the following statistical properties of the SASE FEL radiation: time and spectral field correlation functions, distribution of the fluctuations of the instantaneous radiation power, distribution of the energy in the electron bunch, distribution of the radiation energy after monochromator installed at the FEL amplifier exit and the radiation spectrum. All numerical results presented in the paper have been calculated for the 70 nm SASE FEL at the TESLA Test Facility being under construction at DESY

  11. PSI: Upgrading

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    The accelerator complex at the Paul Scherrer Institute in Villigen near Zurich (PSI - formed in 1988 by combining the Federal Institute for Reactor Research and the Swiss Institute for Nuclear Research) is in the throes of a major and lengthy upgrade

  12. PSI: Upgrading

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1992-09-15

    The accelerator complex at the Paul Scherrer Institute in Villigen near Zurich (PSI - formed in 1988 by combining the Federal Institute for Reactor Research and the Swiss Institute for Nuclear Research) is in the throes of a major and lengthy upgrade.

  13. ATA upgrade to 150 MeV

    International Nuclear Information System (INIS)

    Birx, D.L.; Hawkins, S.A.; Poor, S.E.; Reginato, L.L.; Smith, M.W.

    1985-01-01

    The increased interests in upgrading the ATA accelerator has warranted a preliminary look at applying the magnetic drivers to achieve both higher energy and higher average power. The goal of this upgrade is to satisfy the FEL requirements and to keep the capability of producing a higher current beam for CPB experiments at reduced energy. ATA Note 247 showed that a possible solution to obtain higher energy was simply to add additional cells, run them at higher voltage and accept a 30 ns pulse width with about 5% energy variation. Considering the recent history of the cells and the doubling of the voltage stress that would be required at the insulator, it seemed prudent to review the overall system reliability and try a different approach

  14. Ultrahigh harmonics generation in a FEL with a seed laser

    International Nuclear Information System (INIS)

    Goloviznin, V.V.; Amersfoort, P.W. van

    1995-01-01

    One of the most challenging problems in modern FEL technology is to operate in the X-ray region, especially in the open-quotes water windowclose quotes. Because of the absence of optical resonators in this range of wavelengths, only a single-pass device may be suitable for this task. The Self-Amplified Spontaneous Emission (SASE) mechanism is now under active discussion as a realistic way to provide high-power coherent emission in the X-ray range. Both the undulator parameters and the electron beam parameters required for the lasing are achieveable at today's technological level. On the other hand, the SASE approach implies a very long and expensive periodic magnetic structure, typically several tens of meters long. This is mainly because of the rather long build-up time necessary to establish a coherent mode from incoherent noise. A mechanism of shortening this time would be therefore highly desirable. In the present paper we consider a scheme using two undulators and a seed-laser to produce coherent X-ray emission. The first undulator and the seed-laser provide a pre-modulation of the beam while the second undulator serves as a source of coherent spontaneous radiation at a very high harmonic of the seed-laser frequency; the whole scheme may then be considered to be an FEL-based frequency upconvertor. The total length of the periodic magnetic structure is shown to be of the order of several meters, nearly an order of magnitude shorter than in the SASE case. For the same beam quality as in the SASE scheme and with realistic seed-laser parameters, the efficiency of the beam pre-modulation at the 50-th (exclamation point) harmonic is shown to be as high as 15%. The output radiation is tunable between discrete harmonics of the seed-frequency

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

    Energy Technology Data Exchange (ETDEWEB)

    Geloni, Gianluca [European XFEL GmbH, Hamburg (Germany); Kocharyan, Vitali; Saldin, Evgeni [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2010-11-15

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

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

    International Nuclear Information System (INIS)

    Geloni, Gianluca; Kocharyan, Vitali; Saldin, Evgeni

    2010-11-01

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

  17. Wavelength and power stability measurements of the Stanford SCA/FEL

    International Nuclear Information System (INIS)

    van der Geer, B.; de Loos, M.J.; Conde, M.E.; Leemans, W.P.

    1994-08-01

    Wavelength and power stability of the Stanford infrared SCA/FEL operating with the TRW wiggler have been measured using a high-resolution spectrometer and an image dissector system. The image dissector is capable of reading the spectrum of every single micropulse at 12 MHz throughout a macropulse of up to 2 ms duration. The intrinsic wavelength and power stability of the SCA/FEL are found to be δλ/λ=0.035% and δP/P=18%. The use of a feedback control system to stabilize the wavelength, and an acousto-optic modulator for output power smoothing, improves the performance to δλ/λ=0.012% and δP/P=7%

  18. Proposed uv-FEL user facility at BNL

    International Nuclear Information System (INIS)

    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.

    1991-01-01

    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

  19. Progress toward a soft X-ray FEL

    International Nuclear Information System (INIS)

    Pellegrini, C.

    1988-01-01

    We review the FEL physics and obtain scaling laws for the extension of its operation to the soft X-ray region. We also discuss the properties of an electron beam needed to drive such an FEL, and the present state of the art for the beam production. (orig.)

  20. Elements of a realistic 17 GHz FEL/TBA design

    International Nuclear Information System (INIS)

    Hopkins, D.B.; Halbach, K.; Hoyer, E.H.; Sessler, A.M.; Sternbach, E.J.

    1989-01-01

    Recently, renewed interest in an FEL version of a two-beam accelerator (TBA) has prompted a study of practical system and structure designs for achieving the specified physics goals. This paper presents elements of a realistic design for an FEL/TBA suitable for a 1 TeV, 17 GHz linear collider. 13 refs., 8 figs., 2 tabs

  1. X-ray beam splitting design for concurrent imaging at hard X-ray FELs and synchrotron facilities

    Czech Academy of Sciences Publication Activity Database

    Oberta, Peter; Mokso, R.

    2013-01-01

    Roč. 729, NOV (2013), s. 85-89 ISSN 0168-9002 R&D Projects: GA MPO FR-TI1/412 Institutional research plan: CEZ:AV0Z10100522 Keywords : diffractive-refractive optics * hard X-ray FEL * X-ray imaging Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.316, year: 2013 http://www.sciencedirect.com/science/article/pii/S0168900213009613

  2. Harmonic Inverse FEL Interaction at 800nm

    CERN Document Server

    Sears, C M S; Siemann, R; Spencer, J E

    2005-01-01

    The inverse Free Electron Laser (IFEL) interaction has recently been proposed and demonstrated as a premodulator for High Gain Harmonic Generation (HGHG) experiments. These experiments utilized the fundamental of the interaction between the laser field and electron bunch. In the current experiment, we explore the higher order resonances of the IFEL interaction from a 3 period, 1.8 centimeter wavelength undulator with a picosecond, 0.25 mJ/pulse laser at 800nm. The resonances are observed by adjusting the gap of the undulator while keeping the beam energy constant. The harmonic IFEL can add flexibility to HGHG FEL design.

  3. Detection Performance of Upgraded "Polished Panel" Optical Receiver Concept on the Deep-Space Network's 34 Meter Research Antenna

    Science.gov (United States)

    Vilnrotter, Victor A.

    2012-01-01

    The development and demonstration of a "polished panel" optical receiver concept on the 34 meter research antenna of the Deep Space Network (DSN) has been the subject of recent papers. This concept would enable simultaneous reception of optical and microwave signals by retaining the original shape of the main reflector for microwave reception, but with the aluminum panels polished to high reflectivity to enable focusing of optical signal energy as well. A test setup has been installed on the DSN's 34 meter research antenna at Deep Space Station 13 (DSS-13) of NASA's Goldstone Communications Complex in California, and preliminary experimental results have been obtained. This paper describes the results of our latest efforts to improve the point-spread function (PSF) generated by a custom polished panel, in an attempt to reduce the dimensions of the PSF, thus enabling more precise tracking and improved detection performance. The design of the new mechanical support structure and its operation are described, and the results quantified in terms of improvements in collected signal energy and optical communications performance, based on data obtained while tracking the planet Jupiter with the 34 meter research antenna at DSS-13.

  4. The Swiss Education and Research Network - SWITCH - Upgrades Optical Network to Transport 10 Gbps Using Sorrento Networks DWDM Platform

    CERN Multimedia

    2003-01-01

    "Sorrento Networks, a supplier of optical transport networking equipment for carriers and enterprises worldwide, today announced that SWITCH successfully completed 10 Gbps BER tests on the 220 km Zurich to Manno and 360 km Zurich to Geneva links in September and November 2003, using Sorrento's GigaMux DWDM system" (1/2 page).

  5. The ARC-EN-CIEL FEL Proposal

    CERN Document Server

    Couprie, M E

    2005-01-01

    ARC-EN-CIEL (Accelerator-Radiation for Enhanced Coherent Intense Extended Light), the French project of a fourth generation light source aims at providing the user community with coherent femtosecond light pulses covering from UV to soft X ray. It is based on a CW 1 GeV superconducting linear accelerator delivering high charge, subpicosecond, low emittance electron bunches with a high repetition rate. The FEL is based on in the injection of High Harmonics in Gases in a High Gain Harmonic Generation scheme, leading to a rather compact solution. The produced radiation extending down to 0.8 nm with the Non Linear Harmonic reproduces the good longitudinal and transverse coherence of the harmonics in gas. Optional beam loops are foreseen to increase the beam current or the energy. They will accommodate fs synchrotron radiation sources in the IR, VUV and X ray ranges and a FEL oscillator in the 10 nm range. An important synergy is expected between accelerator and laser communities. Indeed, electron plasma accelerat...

  6. Coal upgrading

    Energy Technology Data Exchange (ETDEWEB)

    Nunes, S. [IEA Clean Coal Centre, London (United Kingdom)

    2009-10-15

    This report examines current technologies and those likely to be used to produce cleaner coal and coal products, principally for use in power generation and metallurgical applications. Consideration is also given to coal production in the leading coal producing countries, both with developed and developing industries. A range of technologies are considered. These include the coal-based liquid fuel called coal water mixture (CWM) that may compete with diesel, the production of ultra-clean coal (UCC) and coal liquefaction which competes with oil and its products. Technologies for upgrading coal are considered, especially for low rank coals (LRC), since these have the potential to fill the gap generated by the increasing demand for coal that cannot be met by higher quality coals. Potential advantages and downsides of coal upgrading are outlined. Taking into account the environmental benefits of reduced pollution achieved through cleaner coal and reduced transport costs, as well as other positive aspects such as a predictable product leading to better boiler design, the advantages appear to be significant. The drying of low rank coals improves the energy productively released during combustion and may also be used as an adjunct or as part of other coal processing procedures. Coal washing technologies vary in different countries and the implications of this are outlined. Dry separation technologies, such as dry jigging and electrostatic separation, are also described. The demonstration of new technologies is key to their further development and demonstrations of various clean coal technologies are considered. A number of approaches to briquetting and pelletising are available and their use varies from country to country. Finally, developments in upgrading low rank coals are described in the leading coal producing countries. This is an area that is developing rapidly and in which there are significant corporate and state players. 81 refs., 32 figs., 3 tabs.

  7. Design and implementation of Web-based SDUV-FEL engineering database system

    International Nuclear Information System (INIS)

    Sun Xiaoying; Shen Liren; Dai Zhimin; Xie Dong

    2006-01-01

    A design of Web-based SDUV-FEL engineering database and its implementation are introduced. This system will save and offer static data and archived data of SDUV-FEL, and build a proper and effective platform for share of SDUV-FEL data. It offers usable and reliable SDUV-FEL data for operators and scientists. (authors)

  8. FTIR Spectroscopy on Basic Materials in THz Region for Compact FEL-Based Imaging

    CERN Document Server

    Cha, H J; Lee, B C; Park, S H

    2005-01-01

    We are making experiments on THz(terahertz) imaging using a compact high power FEL (free-electron laser) which is operating as a users facility at KAERI. The wavelength range of output pulses is 100~1200 μm, which corresponds to 0.3~3 THz in the frequency region. We should select the optimum wavelength for the constituents of specimens to realize the imaging based on the THz FEL. A FTIR (Fourier-transform infrared) spectrometer was modified to measure the optical constants of the specimens in THz region. A polyester film of which thickness is 3.7 μm was used as a beam splitter of the spectrometer. In the case of normal incidence, the transmittance of the film was measured to be more than 90%, and the estimated loss by absorption was approximately 2% at the FEL frequency of 3 THz. Several tens of nanometer-thick-silver was coated on the polyester film to balance both transmission and reflection of THz waves in the beam splitter. We investigated FTIR spectroscopy on air, vapor and liquid water...

  9. Commissioning experience and beam physics measurements at the SwissFEL Injector Test Facility

    Directory of Open Access Journals (Sweden)

    T. Schietinger

    2016-10-01

    Full Text Available The SwissFEL Injector Test Facility operated at the Paul Scherrer Institute between 2010 and 2014, serving as a pilot plant and test bed for the development and realization of SwissFEL, the x-ray Free-Electron Laser facility under construction at the same institute. The test facility consisted of a laser-driven rf electron gun followed by an S-band booster linac, a magnetic bunch compression chicane and a diagnostic section including a transverse deflecting rf cavity. It delivered electron bunches of up to 200 pC charge and up to 250 MeV beam energy at a repetition rate of 10 Hz. The measurements performed at the test facility not only demonstrated the beam parameters required to drive the first stage of an FEL facility, but also led to significant advances in instrumentation technologies, beam characterization methods and the generation, transport and compression of ultralow-emittance beams. We give a comprehensive overview of the commissioning experience of the principal subsystems and the beam physics measurements performed during the operation of the test facility, including the results of the test of an in-vacuum undulator prototype generating radiation in the vacuum ultraviolet and optical range.

  10. FERMI @ Elettra A Seeded Harmonic Cascade FEL for EUV and Soft X-Rays

    CERN Document Server

    Bocchetta, C J; Craievich, P; D'Auria, G; Danailov, M B; De Ninno, G; Di Mitri, S; Diviacco, B; Ferianis, M; Gomezel, A; Iazzourene, F; Karantzoulis, E; Penco, G; Trovò, M

    2005-01-01

    We describe the machine layout and major performance parameters for the FERMI FEL project funded for construction at Sincrotrone Trieste, Italy. The project will be the first user facility based on seeded harmonic cascade FELs, providing controlled, high peak-power pulses. With a high-brightness rf photocathode gun, and using the existing 1.2 GeV S-band linac, the facility will provide tunable output over a range from ~100 nm to ~10 nm, with pulse duration from 40 fs to ~ 1ps, and with fully variable output polarization. Initially, two FEL cascades are planned; a single-stage harmonic generation to operate > 40 nm, and a two-stage cascade operating from ~40 nm to ~10 nm or shorter wavelength. The output is spatially and temporally coherent, with peak power in the GW range. Lasers provide modulation to the electron beam, as well as driving the photocathode and other systems, and the facility will integrate laser systems with the accelerator infrastructure, including a state-of-the-art optical timing sys...

  11. The Present Applications of IR FEL at Peking University

    CERN Document Server

    Yang Li Min; Zhao, Kui

    2004-01-01

    In this study the sections of human tissues were treated under 9.5 μm FEL in the BFEL based on the vibrational spectroscopic investigation that significant differences occur between normal and malignant tissues. Under the defocus condition, the burning of tissue section at some part while other part remains unchanged, suggesting that the FEL can selectively destroy some part of tissue. Vibrational spectroscopic and microscopic methods have shown that the FEL can induce decomposition of malignant tissues. The application of FEL whose wavelength is on the characteristic bands of malignant tissues may provide a new method to kill cancer cells with higher selectivity. For understanding the interactions between FEL and biological tissues, structure changes of substances under irradiation by FEL of 9.414 μm and 6.228 μm were measured using FTIR spectroscopy. The samples include ATP, ADP, AMP, and D-ribose, etc. The FTIR spectra of the molecules before and after irradiation of FEL indicate...

  12. FEL induced molecular operation on cultured fibroblast and cholesterol ester

    International Nuclear Information System (INIS)

    Awazu, Kunio; Ogino, Seiji; Nishimura, Eiichi; Tomimasu, Takio; Yasumoto, Masato.

    1997-01-01

    Free Electron Lasers can be used to molecular operation such as the delivery of a number of molecules into cells or the separation of cholesterol ester. First, cultured NIH3T3 cells are exposed to high-intensity short pulse Free Electron Laser (FEL). The FEL is tuned to an absorption maximum wavelength, 6.1 μm, which was measured by microscopic FTIR. A fluorescence dye in the cell suspension is more absorbed into the cell with the FEL exposure due to the FEL-induced mechanical stress to the cell membrane. A quantitative fluorescence microscopy is used to determine the efficiency of delivery. Second, as a compound in a lipid cell, cholesterol ester was exposed to 5.75 μm FEL. FTIR measurement was done to evaluate the modification of the cholesterol ester. The result showed that the fluorescence intensity of sample cells were higher than that of control cells, and there was significant difference between the control and the sample group. Blebbing and the colony formation of the cells were observed for cells with mechanical stress. As for the cholesterol ester, it can be modified by the FEL irradiation. These results showed that FEL can be used as a molecular operational tool by photo-chemical and photo-mechanical interaction. (author)

  13. High-power FEL design issues - a critical review

    Energy Technology Data Exchange (ETDEWEB)

    Litvinenko, V.N.; Madey, J.M.J.; O`Shea, P.G. [Duke Univ., Durham, NC (United States)

    1995-12-31

    The high-average power capability of FELs has been much advertised but little realized. In this paper we provide a critical analysis of the technological and economic issues associated with high-average power FEL operation from the UV to near IR. The project of IR FEL for the Siberian Center of photochemical researches is described. The distinguished features of this project are the use of the race-track microtron-recuperator and the {open_quotes}electron output of radiation{close_quotes}. The building for the machine is under reconstruction now. About half of hardware has been manufactured. The assembly of installation began.

  14. Undulator systems for the TESLA X-FEL

    International Nuclear Information System (INIS)

    Pflueger, J.; Tischer, M.

    2002-01-01

    A large X-ray FEL lab is under consideration within the TESLA project and is supposed to be operated in parallel with the TESLA linear collider. There will be five SASE FELs and five conventional spontaneous undulators. A conceptual design study has been made for the undulator systems for these X-FELs. It includes segmentation into 6.1 m long undulator 'cells'. Each consists of a 5 m long undulator 'segment', a separate quadrupole, one horizontal and one vertical corrector, and a phase shifter. These items are presented and discussed

  15. Status of the Novosibirsk high-power terahertz FEL

    International Nuclear Information System (INIS)

    Gavrilov, N.G.; Knyazev, B.A.; Kolobanov, E.I.; Kotenkov, V.V.; Kubarev, V.V.; Kulipanov, G.N.; Matveenko, A.N.; Medvedev, L.E.; Miginsky, S.V.; Mironenko, L.A.; Oreshkov, A.D.; Ovchar, V.K.; Popik, V.M.; Salikova, T.V.; Scheglov, M.A.; Serednyakov, S.S.; Shevchenko, O.A.; Skrinsky, A.N.; Tcheskidov, V.G.; Vinokurov, N.A.

    2007-01-01

    The first stage of Novosibirsk high-power free electron laser (FEL) was commissioned in 2003. It is based on the normal conducting CW energy recovery linac (ERL). Now the FEL provides electromagnetic radiation in the wavelength range 120-230 μm. The maximum average power is 400 W. The minimum measured linewidth is 0.3%, which is close to the Fourier-transform limit. Four user stations are in operation now. Manufacturing of the second stage of the FEL (based on the four-turn ERL) is in progress

  16. Development of a pump-probe facility with sub-picosecond time resolution combining a high-power ultraviolet regenerative FEL amplifier and a soft X-ray SASE FEL

    International Nuclear Information System (INIS)

    Faatz, B.; Fateev, A.A.; Feldhaus, J.; Krzywinski, J.; Pflueger, J.; Rossbach, J.; Saldin, E.L.; Schneidmiller, E.A.; Yurkov, M.V.

    2001-01-01

    This paper presents the conceptual design of a high power radiation source with laser-like characteristics in the ultraviolet spectral range at the TESLA Test Facility (TTF). The concept is based on the generation of radiation in a regenerative FEL amplifier (RAFEL). The RAFEL described in this paper covers a wavelength range of 200-400 nm and provides 200 fs pulses with 2 mJ of optical energy per pulse. The linac operates at 1% duty factor and the average output radiation power exceeds 100 W. The RAFEL will be driven by the spent electron beam leaving the soft X-ray FEL, thus providing minimal interference between these two devices. The RAFEL output radiation has the same time structure as the X-ray FEL and the UV pulses are naturally synchronized with the soft X-ray pulses from the TTF FEL. Therefore, it should be possible to achieve synchronization close to the duration of the radiation pulses (200 fs) for pump-probe techniques using either an UV pulse as a pump and soft X-ray pulse as a probe, or vice versa

  17. Tunable driver for the LLNL FEL experiment

    International Nuclear Information System (INIS)

    Guss, W.C.; Basten, M.A.; Kreischer, K.E.; Temkin, R.J.

    1991-07-01

    This report describes main activities undertaken during the period 1 June 1990 to 1 June 1991 by MIT to support the Lawrence Livermore National Laboratory tunable FEL driver project. The goal of this research was to further characterize a tunable microwave source (already identified as a BWO-gyrotron) of moderate output power (10--20 kW). In the 1989 fiscal year, the source was assembled at MIT and initial tests were conducted. Proposed for the fiscal year 1990 were analysis of the previous experimental results, and the performance of new experiments designed to increase the voltage tuning range, the output efficiency, and magnetic field tuning. During the report period the previous experimental results were analyzed and compared to computational results and new components were designed, to make the BWO ready for further experiments. In addition, the BWO-gyrotron was mounted in a new superconducting magnet and initial magnetic field profile measurements were made

  18. Design of a high average-power FEL driven by an existing 20 MV electrostatic-accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Kimel, I.; Elias, L.R. [Univ. of Central Florida, Orlando, FL (United States)

    1995-12-31

    There are some important applications where high average-power radiation is required. Two examples are industrial machining and space power-beaming. Unfortunately, up to date no FEL has been able to show more than 10 Watts of average power. To remedy this situation we started a program geared towards the development of high average-power FELs. As a first step we are building in our CREOL laboratory, a compact FEL which will generate close to 1 kW in CW operation. As the next step we are also engaged in the design of a much higher average-power system based on a 20 MV electrostatic accelerator. This FEL will be capable of operating CW with a power output of 60 kW. The idea is to perform a high power demonstration using the existing 20 MV electrostatic accelerator at the Tandar facility in Buenos Aires. This machine has been dedicated to accelerate heavy ions for experiments and applications in nuclear and atomic physics. The necessary adaptations required to utilize the machine to accelerate electrons will be described. An important aspect of the design of the 20 MV system, is the electron beam optics through almost 30 meters of accelerating and decelerating tubes as well as the undulator. Of equal importance is a careful design of the long resonator with mirrors able to withstand high power loading with proper heat dissipation features.

  19. Extension of the spectral range of the CLIO FEL

    Energy Technology Data Exchange (ETDEWEB)

    Marcouille, O.; Boyer, J.C.; Corlier, M. [LURE, Orsay (France)] [and others

    1995-12-31

    The CLIO FEL has been designed to lase between 2 and 20 {mu}m. The electrons are produced by a 32/50 MeV RF linear accelerator. The injector is a 100 keV thermoionic gun, followed by a subharmonic prebuncher at 0.5 GHz and a buncher at 3 GHz. The electron beam is then accelerated in a 4.5 m long travelling wave accelerating section, to the nominal energy. The undulator consisted of 48 periods of 40 mm and the optical cavity is 4.8 m long which corresponds to a 1.2 m Rayleigh length. The peak power extracted by a ZnSe Brewster plate is 10 MW at 10 {mu}. But, beyond 11{mu}m, the laser power decreases rapidely and no laser oscillation appears above 17 {mu}m. In order to lase at farther wavelengths, few changes have been made: First of all, the power limit is due to the diffraction losses of the undulator vaccuum chamber (7 mm height and 2 m long). Numerical calculations have been made and show that cavity losses reach 55 % at 15 {mu}m whereas the measured gain is 60 %. Consequently, the undulator vaccuum chamber have been replaced by a approximately twice bigger one. Then, the minimum gap is increased and the maximum deflection parameter K is reduced by a factor 2: laser tunability is greatly reduced. This why a new undulator has been built. The main characteristics are summarized.

  20. Beam dynamics simulations for linacs driving short-wavelength FELs

    International Nuclear Information System (INIS)

    Ferrario, M.; Tazzioli, F.

    1999-01-01

    The fast code HOMDYN has been recently developed, in the framework of the TTF (Tesla test facility) collaboration, in order to study the beam dynamics of linacs delivering high brightness beams as those needed for short wavelength Fel experiments. These linacs are typically driven by radio-frequency photo-injectors, where correlated time dependent space charge effects are of great relevance: these effects cannot be studied by standard beam optics codes (TRACE3D, etc.) and they have been modeled so far by means of multi-particle (Pic or quasistatic) codes requiring heavy cpu time and memory allocations. HOMDYN is able to describe the beam generation at the photo-cathode and the emittance compensation process in the injector even running on a laptop with very modest running rimes (less than a minute). In this paper it is showed how this capability of the code is exploited so to model a whole linac up to the point where the space charge dominated regime is of relevance (200 MeV)

  1. Milestone experiments for single pass UV/X-ray FELs

    International Nuclear Information System (INIS)

    Ben-Zvi, I.

    1994-01-01

    In the past decade, significant advances have been made in the theory and technology of high brightness electron beams and single pass FELS. These developments facilitate the construction of practical UV and X-ray FELs and has prompted proposals to the DOE for the construction of such facilities. There are several important experiments to be performed before committing to the construction of dedicated user facilities. Two experiments are under construction in the IR, the UCLA Self Amplified Spontaneous Emission experiment and the BNL laser seeded Harmonic Generation experiment. A multi-institution collaboration is being organized about a 210 MeV electron linac available at BNL and the 10 meter tong NISUS wiggler. This experiment will be done in the UV and will test various experimental aspects of electron beam dynamics, FEL exponential regime with gain guiding, start up from noise, seeding and harmonic generation. These experiments will advance the state of FEL research and lead towards future dedicated users' facilities

  2. A 20fs synchronization system for lasers and cavities in accelerators and FELs

    Science.gov (United States)

    Wilcox, R. B.; Byrd, J. M.; Doolittle, L. R.; Huang, G.; Staples, J. W.

    2010-02-01

    A fiber-optic RF distribution system has been developed for synchronizing lasers and RF plants in short pulse FELs. Typical requirements are 50-100fs rms over time periods from 1ms to several hours. Our system amplitude modulates a CW laser signal, senses fiber length using an interferometer, and feed-forward corrects the RF phase digitally at the receiver. We demonstrate less than 15fs rms error over 12 hours, between two independent channels with a fiber path length difference of 200m and transmitting S-band RF. The system is constructed using standard telecommunications components, and uses regular telecom fiber.

  3. Accelerator Physics Challenges of X-Ray FEL SASE Sources

    Energy Technology Data Exchange (ETDEWEB)

    Emma, Paul J

    2002-05-30

    A great deal of international interest has recently focused on the design and construction of free-electron lasers (FEL) operating in the x-ray region ({approx}1 {angstrom}). At present, a linac-based machine utilizing the principle of self-amplified spontaneous emission (SASE) appears to be the most promising approach. This new class of FEL achieves lasing in a single pass of a high brightness electron beam through a long undulator. The requirements on electron beam quality become more demanding as the FEL radiation wavelength decreases, with the 1-{angstrom} goal still 3-orders of magnitude below the shortest wavelength operational SASE FEL (TTF-FEL at DESY [1]). The subpicosecond bunch length drives damaging effects such as coherent synchrotron radiation, and undulator vacuum chamber wakefields. Unlike linear colliders, beam brightness needs to be maintained only over a small ''slice'' of the bunch length, so the concepts of bunch integrated emittance and energy spread are less relevant than their high-frequency (or ''time-sliced'') counterparts, also adding a challenge to phase space diagnostics. Some of the challenges associated with the generation, preservation, measurement, and stability of high brightness FEL electron beams are discussed here.

  4. Design of compressors for FEL pulses using deformable gratings

    Science.gov (United States)

    Bonora, Stefano; Fabris, Nicola; Frassetto, Fabio; Giovine, Ennio; Miotti, Paolo; Quintavalla, Martino; Poletto, Luca

    2017-06-01

    We present the optical layout of soft X-rays compressors using reflective grating specifically designed to give both positive or negative group-delay dispersion (GDD). They are tailored for chirped-pulse-amplification experiments with FEL sources. The optical design originates from an existing compressor with plane gratings already realized and tested at FERMI, that has been demonstrated capable to introduce tunable negative GDD. Here, we discuss two novel designs for compressors using deformable gratings capable to give both negative and positive GDD. Two novel designs are discussed: 1) a design with two deformable gratings and an intermediate focus between the twos, that is demonstrated capable to introduce positive GDD; 2) a design with one deformable grating giving an intermediate focus, followed by a concave mirror and a plane grating, that is capable to give both positive and negative GDD depending on the distance between the second mirror and the second grating. Both the designs are tunable in wavelength and GDD, by acting on the deformable gratings, that are rotated to tune the wavelength and the GDD and deformed to introduce the radius required to keep the spectral focus. The deformable gratings have a laminar profile and are ruled on a thin silicon plane substrate. A piezoelectric actuator is glued on the back of the substrate and is actuated to give a radius of curvature that is varying from infinite (plane) to few meters. The ruling procedure, the piezoelectric actuator and the efficiency measurements in the soft X-rays will be presented. Some test cases are discussed for wavelengths shorter than 12 nm.

  5. Effect of FEL induced ionization on X-ray reflectivity of multilayers

    Energy Technology Data Exchange (ETDEWEB)

    Ksenzov, Dmitriy; Grigorian, Souren; Pietsch, Ullrich [University of Siegen (Germany)

    2009-07-01

    The VUV-FEL in Hamburg (FLASH) emits short-pulse radiation with wavelengths from 6 to 30 nm and a pulse length of 10-50 fs. The FLASH wavelength allows x-ray diffraction experiments at periodical multilayer's structures acting as 1D crystal. The probe of depth selective interaction of the high-intense x-ray short pulse with these objects can be used to obtain information about possible electronic excitation and various recombination processes inside multilayers. As known from recent experiments at FLASH, the later ones are most likely using highly intense FEL radiation. The ML reflectivity is analyzed for case of that the optical parameters are changing as function of the depth of the penetrating incident pulse into the multilayer. The response is studied for the model system La/B{sub 4}C using two experimental conditions both at fixed incidence angle: 1) the energy of the incident pulses, E, coincides with the energy of the 1st order multilayer Bragg peak, E{sub B}, of the reflection curve, and 2) the energy of incident pulse differs by a small dE from E{sub B}. The ML response to a given sub-pulse differs for both conditions. However, there is a clear fingerprint of ionization for both conditions for the case that E is close to the K-absorption edge of B-atoms. Our results support respective efforts to measure the optical parameters of solids under high-intense FEL radiation.

  6. Electron gun for the Fel Clio

    International Nuclear Information System (INIS)

    Chaput, R.

    1990-01-01

    A triode electron gun has been developed and manufactured at LURE (Laboratoire pour l'Utilisation du Rayonnement Electromagnetique) and LAL (Laboratoire de l'Accelerateur Lineaire) for the free electron laser CLIO 1 (Collaboration pour un laser a electrons libres dans l'infrarouge a Orsay) now under construction: this gun involves a grid-cathode assembly manufactured by EIMAC, currently used in the SLAC gun family. For the FEL requirements, the gun must be able to yield a train of short pulses at accuracy frequency or a continuous pulse. Driving together the cathode and the grid the gun produces a continous beam of 12 μs or a pulsed beam of very short pulse of 1 ns at 250 MHz, 125 MHz, 62.5 MHz or 31.25 MHz. The performances of the gun has been tested on a testing bench. A peak current of 1 Amp. for 1 ns width at any frequencies was achieved at an injection voltage of 90 kV

  7. Design considerations of 10 kW-scale, extreme ultraviolet SASE FEL for lithography

    CERN Document Server

    Pagani, C; Schneidmiller, E A; Yurkov, M V

    2001-01-01

    The semiconductor industry growth is driven to a large extent by steady advancements in microlithography. According to the newly updated industry road map, the 70 nm generation is anticipated to be available in the year 2008. However, the path to get there is not clear. The problem of construction of extreme ultraviolet (EUV) quantum lasers for lithography is still unsolved: progress in this field is rather moderate and we cannot expect a significant breakthrough in the near future. Nevertheless, there is clear path for optical lithography to take us to sub-100 nm dimensions. Theoretical and experimental work in Self-Amplified Spontaneous Emission (SASE) Free Electron Lasers (FEL) physics and the physics of superconducting linear accelerators over the last 10 years has pointed to the possibility of the generation of high-power optical beams with laser-like characteristics in the EUV spectral range. Recently, there have been important advances in demonstrating a high-gain SASE FEL at 100 nm wavelength (J. Andr...

  8. Analysis and comparison between electric and magnetic power couplers for accelerators in Free Electron Lasers (FEL)

    Energy Technology Data Exchange (ETDEWEB)

    Serpico, C., E-mail: claudio.serpico@elettra.eu [Elettra - Sincrotrone Trieste, Trieste (Italy); Grudiev, A. [CERN, Geneva (Switzerland); Vescovo, R. [University of Trieste, Trieste (Italy)

    2016-10-11

    Free-electron lasers represent a new and exciting class of coherent optical sources possessing broad wavelength tunability and excellent optical-beam quality. The FERMI seeded free-electron laser (FEL), located at the Elettra laboratory in Trieste, is driven by a 200 m long, S-band linac: the high energy part of the linac is equipped with 6 m long backward traveling wave (BTW) structures. The structures have small iris radius and a nose cone geometry which allows for high gradient operation. Development of new high-gradient, S-band accelerating structures for the replacement of the existing BTWs is under consideration. This paper investigates two possible solutions for the RF power couplers suitable for a linac driven FEL which require reduced wakefields effects, high operating gradient and very high reliability. The first part of the manuscript focuses on the reduction of residual field asymmetries, while in the second analyzes RF performances, the peak surface fields and the expected breakdown rate. In the conclusion, two solutions are compared and pros and cons are highlighted.

  9. Analysis and comparison between electric and magnetic power couplers for accelerators in Free Electron Lasers (FEL)

    Science.gov (United States)

    Serpico, C.; Grudiev, A.; Vescovo, R.

    2016-10-01

    Free-electron lasers represent a new and exciting class of coherent optical sources possessing broad wavelength tunability and excellent optical-beam quality. The FERMI seeded free-electron laser (FEL), located at the Elettra laboratory in Trieste, is driven by a 200 m long, S-band linac: the high energy part of the linac is equipped with 6 m long backward traveling wave (BTW) structures. The structures have small iris radius and a nose cone geometry which allows for high gradient operation. Development of new high-gradient, S-band accelerating structures for the replacement of the existing BTWs is under consideration. This paper investigates two possible solutions for the RF power couplers suitable for a linac driven FEL which require reduced wakefields effects, high operating gradient and very high reliability. The first part of the manuscript focuses on the reduction of residual field asymmetries, while in the second analyzes RF performances, the peak surface fields and the expected breakdown rate. In the conclusion, two solutions are compared and pros and cons are highlighted.

  10. FEL polarization control studies on Dalian coherent light source

    International Nuclear Information System (INIS)

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

    2013-01-01

    The polarization switch of a free-electron laser (FEL) is of great importance to the user scientific community. In this paper, we investigate the generation of controllable polarization FEL from two well-known approaches for Dalian coherent light source, i.e., crossed planar undulator and elliptical permanent undulator. In order to perform a fair comparative study, a one-dimensional time-dependent FEL code has been developed, in which the imperfection effects of an elliptical permanent undulator are taken into account. Comprehensive simulation results indicate that the residual beam energy chirp and the intrinsic FEL gain may contribute to the degradation of the polarization performance for the crossed planar undulator. The elliptical permanent undulator is not very sensitive to the undulator errors and beam imperfections. Meanwhile, with proper configurations of the main planar undulators and additional elliptical permanent undulator section, circular polarized FEL with pulse energy exceeding 100 μJ could be achieved at Dalian coherent light source. (authors)

  11. FERMI(at)Elettra FEL Design Technical Optimization Final Report

    International Nuclear Information System (INIS)

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

    2006-01-01

    This is the final report of the FEL Design Group for the Technical Optimization Study for the FERMI(at)ELETTRA project. The FERMI(at)ELETTRA project is based on the principle of harmonic upshifting of an initial ''seed'' signal in a single pass, FEL amplifier employing multiple undulators. There are a number of FEL physics principles which underlie this approach to obtaining short wavelength output: (1) the energy modulation of the electron beam via the resonant interaction with an external laser seed (2) the use of a chromatic dispersive section to then develop a strong density modulation with large harmonic overtones (3) the production of coherent radiation by the microbunched beam in a downstream radiator. Within the context of the FERMI project, we discuss each of these elements in turn

  12. Towards the Fourier limit on the super-ACO Storage Ring FEL

    International Nuclear Information System (INIS)

    Couprie, M.E.; De Ninno, G.; Moneron, G.; Nutarelli, D.; Hirsch, M.; Garzella, D.; Renault, E.; Roux, R.; Thomas, C.

    2001-01-01

    Systematic studies on the Free Electron Laser (FEL) line and micropulse have been performed on the Super-ACO storage ring FEL with a monochromator and a double-sweep streak camera under various conditions of operation (detuning, 'CW' and Q-switched mode). From these data, it appears that the FEL is usually operated very close to the Fourier limit

  13. Towards the Fourier limit on the super-ACO Storage Ring FEL

    CERN Document Server

    Couprie, Marie Emmanuelle; Garzella, D; Hirsch, M; Moneron, G; Nutarelli, D; Renault, E; Roux, R; Thomas, C

    2001-01-01

    Systematic studies on the Free Electron Laser (FEL) line and micropulse have been performed on the Super-ACO storage ring FEL with a monochromator and a double-sweep streak camera under various conditions of operation (detuning, 'CW' and Q-switched mode). From these data, it appears that the FEL is usually operated very close to the Fourier limit.

  14. Beam transport design for a recirculating-linac FEL driver

    International Nuclear Information System (INIS)

    Neuffer, D.; Douglas, D.; Li, Z.; Cornacchia, M.; Garren, A.

    1996-01-01

    The beam transport system for the CEBAF Industrial FEL includes a two-pass transport of the beam with acceleration from injector to wiggler, followed by energy recovery transport from wiggler to dump. From that context, the authors discuss the general problem of multi-pass energy-recovery beam transport for FELs. Tunable, nearly-isochronous, large-momentum-acceptance transport systems are required. The entire transport must preserve beam quality, particularly in the acceleration transport to the wiggler, and have low losses throughout the entire system. Various possible designs are presented, and results of dynamic analyses are discussed

  15. Beam profile diagnostics system for SDUV-FEL

    International Nuclear Information System (INIS)

    Xu Yichao; Han Lifeng; Chen Yongzhong

    2010-01-01

    A new beam profile diagnostics system for Shanghai Deep Ultraviolet Free Electron Laser (SDUV-FEL) has been developed based on industrial Ethernet, with good versatility and scalability. The system includes three major subsystems for image acquisition,pneumatic control and stepper motor control, respectively. Virtual instrument technology is adopted to drive the devices, and to develop the measurement software. In this paper,we describe the system structure, and its hardware and software design. The results of system commissioning are given as well. As an important diagnostic tool and data acquisition method, the system has been successfully applied to the measurement and control of the SDUV-FEL.(authors)

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

    Energy Technology Data Exchange (ETDEWEB)

    Rizzo, G., E-mail: giuliana.rizzo@pi.infn.it [Università di Pisa, Dipartimento di Fisica, I-56127 Pisa (Italy); INFN, Sezione di Pisa, I-56127 Pisa (Italy); Batignani, G. [Università di Pisa, Dipartimento di Fisica, I-56127 Pisa (Italy); INFN, Sezione di Pisa, I-56127 Pisa (Italy); Benkechkache, M.A. [Università di Trento, Dipartimento di Ingegneria Industriale, I-38123 Trento (Italy); University Constantine 1, Department of Electronics in the Science and Technology Faculty, I-25017, Constantine (Algeria); Bettarini, S.; Casarosa, G. [Università di Pisa, Dipartimento di Fisica, I-56127 Pisa (Italy); INFN, Sezione di Pisa, I-56127 Pisa (Italy); Comotti, D. [Università di Pavia, Dipartimento di Ingegneria Industriale e dell' Informazione, I-27100 Pavia (Italy); INFN Sezione di Pavia, I-27100 Pavia (Italy); Dalla Betta, G.-F. [Università di Trento, Dipartimento di Ingegneria Industriale, I-38123 Trento (Italy); TIFPA INFN, I-38123 Trento (Italy); Fabris, L. [INFN Sezione di Pavia, I-27100 Pavia (Italy); Università di Bergamo, Dipartimento di Ingegneria e Scienze Applicate, I-24044 Dalmine (Italy); Forti, F. [Università di Pisa, Dipartimento di Fisica, I-56127 Pisa (Italy); INFN, Sezione di Pisa, I-56127 Pisa (Italy); Grassi, M.; Lodola, L.; Malcovati, P. [Università di Pavia, Dipartimento di Ingegneria Industriale e dell' Informazione, I-27100 Pavia (Italy); INFN Sezione di Pavia, I-27100 Pavia (Italy); Manghisoni, M. [INFN Sezione di Pavia, I-27100 Pavia (Italy); Università di Bergamo, Dipartimento di Ingegneria e Scienze Applicate, I-24044 Dalmine (Italy); and others

    2016-07-11

    The INFN PixFEL project is developing the fundamental building blocks for a large area X-ray imaging camera to be deployed at next generation free electron laser (FEL) facilities with unprecedented intensity. Improvement in performance beyond the state of art in imaging instrumentation will be explored adopting advanced technologies like active edge sensors, a 65 nm node CMOS process and vertical integration. These are the key ingredients of the PixFEL project to realize a seamless large area focal plane instrument composed by a matrix of multilayer four-side buttable tiles. In order to minimize the dead area and reduce ambiguities in image reconstruction, a fine pitch active edge thick sensor is being optimized to cope with very high intensity photon flux, up to 10{sup 4} photons per pixel, in the range from 1 to 10 keV. A low noise analog front-end channel with this wide dynamic range and a novel dynamic compression feature, together with a low power 10 bit analog to digital conversion up to 5 MHz, has been realized in a 110 μm pitch with a 65 nm CMOS process. Vertical interconnection of two CMOS tiers will be also explored in the future to build a four-side buttable readout chip with high density memories. In the long run the objective of the PixFEL project is to build a flexible X-ray imaging camera for operation both in burst mode, like at the European X-FEL, or in continuous mode with the high frame rates anticipated for future FEL facilities.

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

    International Nuclear Information System (INIS)

    Rizzo, G.; Batignani, G.; Benkechkache, M.A.; Bettarini, S.; Casarosa, G.; Comotti, D.; Dalla Betta, G.-F.; Fabris, L.; Forti, F.; Grassi, M.; Lodola, L.; Malcovati, P.; Manghisoni, M.

    2016-01-01

    The INFN PixFEL project is developing the fundamental building blocks for a large area X-ray imaging camera to be deployed at next generation free electron laser (FEL) facilities with unprecedented intensity. Improvement in performance beyond the state of art in imaging instrumentation will be explored adopting advanced technologies like active edge sensors, a 65 nm node CMOS process and vertical integration. These are the key ingredients of the PixFEL project to realize a seamless large area focal plane instrument composed by a matrix of multilayer four-side buttable tiles. In order to minimize the dead area and reduce ambiguities in image reconstruction, a fine pitch active edge thick sensor is being optimized to cope with very high intensity photon flux, up to 10"4 photons per pixel, in the range from 1 to 10 keV. A low noise analog front-end channel with this wide dynamic range and a novel dynamic compression feature, together with a low power 10 bit analog to digital conversion up to 5 MHz, has been realized in a 110 μm pitch with a 65 nm CMOS process. Vertical interconnection of two CMOS tiers will be also explored in the future to build a four-side buttable readout chip with high density memories. In the long run the objective of the PixFEL project is to build a flexible X-ray imaging camera for operation both in burst mode, like at the European X-FEL, or in continuous mode with the high frame rates anticipated for future FEL facilities.

  18. Statistical properties of SASE FEL radiation: experimental results from the VUV FEL at the TESLA test facility at DESY

    International Nuclear Information System (INIS)

    Yurkov, M.V.

    2002-01-01

    This paper presents an experimental study of the statistical properties of the radiation from a SASE FEL. The experiments were performed at the TESLA Test Facility VUV SASE FEL at DESY operating in a high-gain linear regime with a gain of about 10 6 . It is shown that fluctuations of the output radiation energy follows a gamma-distribution. We also measured for the first time the probability distribution of SASE radiation energy after a narrow-band monochromator. The experimental results are in good agreement with theoretical predictions, the energy fluctuations after the monochromator follow a negative exponential distribution

  19. The Physics and Applications of High Brightness Beams: Working Group C Summary on Applications to FELS

    International Nuclear Information System (INIS)

    Nuhn, Heinz-Dieter

    2003-01-01

    This is the summary of the activities in working group C, ''Application to FELs,'' which was based in the Bithia room at the Joint ICFA Advanced Accelerator and Beam Dynamics Workshop on July 1-6, 2002 in Chia Laguna, Sardinia, Italy. Working group C was small in relation to the other working groups at that workshop. Attendees include Enrica Chiadroni, University of Rome ape with an identical pulse length. ''La Sapienza'', Luca Giannessi, ENEA, Steve Lidia, LBNL, Vladimir Litvinenko, Duke University, Patrick Muggli, UCLA, Alex Murokh, UCLA, Heinz-Dieter Nuhn, SLAC, Sven Reiche, UCLA, Jamie Rosenzweig, UCLA, Claudio Pellegrini, UCLA, Susan Smith, Daresbury Laboratory, Matthew Thompson, UCLA, Alexander Varfolomeev, Russian Research Center, plus a small number of occasional visitors. The working group addressed a total of nine topics. Each topic was introduced by a presentation, which initiated a discussion of the topic during and after the presentation. The speaker of the introductory presentation facilitated the discussion. There were six topics that were treated in stand-alone sessions of working group C. In addition, there were two joint sessions, one with working group B, which included one topic, and one with working group C, which included two topics. The presentations that were given in the joint sessions are summarized in the working group summary reports for groups B and D, respectively. This summary will only discuss the topics that were addressed in the stand-alone sessions, including Start-To-End Simulations, SASE Experiment, PERSEO, ''Optics Free'' FEL Oscillators, and VISA II

  20. End-to-end simulation of a visible 1 kW FEL

    International Nuclear Information System (INIS)

    Parazzoli, Claudio G.; Koltenbah, Benjamin E.C.

    2000-01-01

    In this paper we present the complete numerical simulation of the 1 kW visible Free Electron Laser under construction in Seattle. We show that the goal of producing 1.0 kW at 0.7 μm is well within the hardware capabilities. We simulate in detail the evolution of the electron bunch phase space in the entire e-beam line. The e-beam line includes the photo-injector cavities, the 433.33 MHz accelerator, the magnetic buncher, the 1300 MHz accelerator, the 180 deg. bend and the matching optics into the wiggler. The computed phase space is input for a three-dimensional time-dependent code that predicts the FEL performance. All the computations are based on state of the art software, and the limitations of the current software are discussed. We believe that this is the first time that such a thorough numerical simulation has been carried out and that such a realistic electron phase space has been used in FEL performance calculations

  1. Comments on advanced, time-resolved imaging techniques for free-electron laser (FEL) experiments

    Energy Technology Data Exchange (ETDEWEB)

    Lumpkin, A.H.

    1992-01-01

    An extensive set of time-resolved imaging experiments has been performed on rf-linac driven free-electron lasers (FELs) over the past few years. These experiments have addressed both micropulse and macropulse timescales on both the charged-particle beam and the wiggler/undulator outputs (spontaneous emission and lasing). A brief review of first measurements on photoinjecter micropulse elongation, submacropulse phase slew in drive lasers, submacropulse wavelength shifts in lasers, etc. is presented. This is followed by discussions of new measurements of 35-MeV electron beam micropulse bunch length (<10 ps) using optical transition radiation, some of the first single bend synchrotron radiation beam profile measurements at gamma <80, and comments on the low-jitter synchroscan streak camera tuner. These techniques will be further developed on the 200-650 MeV linac test stand at the Advanced Photon Source (APS) in the next few years. Such techniques should be adaptable to many of the present FEL designs and to some aspects of the next generation of light sources.

  2. Comments on advanced, time-resolved imaging techniques for free-electron laser (FEL) experiments

    Energy Technology Data Exchange (ETDEWEB)

    Lumpkin, A.H.

    1992-11-01

    An extensive set of time-resolved imaging experiments has been performed on rf-linac driven free-electron lasers (FELs) over the past few years. These experiments have addressed both micropulse and macropulse timescales on both the charged-particle beam and the wiggler/undulator outputs (spontaneous emission and lasing). A brief review of first measurements on photoinjecter micropulse elongation, submacropulse phase slew in drive lasers, submacropulse wavelength shifts in lasers, etc. is presented. This is followed by discussions of new measurements of 35-MeV electron beam micropulse bunch length (<10 ps) using optical transition radiation, some of the first single bend synchrotron radiation beam profile measurements at gamma <80, and comments on the low-jitter synchroscan streak camera tuner. These techniques will be further developed on the 200-650 MeV linac test stand at the Advanced Photon Source (APS) in the next few years. Such techniques should be adaptable to many of the present FEL designs and to some aspects of the next generation of light sources.

  3. Optimization Studies of the FERMI at ELETTRA FEL Design

    International Nuclear Information System (INIS)

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

    2005-01-01

    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

  4. Status of the project of Novosibirsk high power FEL

    Energy Technology Data Exchange (ETDEWEB)

    Pinayev, I.V.; Erg, G.I.; Gavrilov, N.G. [Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation)] [and others

    1995-12-31

    The project of IR FEL for the Siberian Center of photochemical researches is described. The distinguished features of this project are the use of the race-track microtron-recuperator and the {open_quotes}electron output of radiation{close_quotes}. The building for the machine is under reconstruction now. About half of hardware has been manufactured. The assembly of installation began.

  5. Colorado State University (CSU) accelerator and FEL facility

    NARCIS (Netherlands)

    Milton, S.; Biedron, S.; Harris, J.; Martinez, J.; D'Audney, A.; Edelen, J.; Einstein, J.; Hall, C.; Horovitz, K.; Morin, A.; Sipahi, N.; Sipahi, T.; Williams, J.; Carrico, C.; Van Der Slot, P. J M

    2014-01-01

    The Colorado State University (CSU) Accelerator Facility will include a 6-MeV L-Band (1.3 GHz) electron linear accelerator (linac) with a free-electron laser (FEL) system capable of producing Terahertz (THz) radiation, a laser laboratory, a microwave test laboratory, and a magnetic test laboratory.

  6. Towards imaging of ultrafast molecular dynamics using FELs

    NARCIS (Netherlands)

    Rouzee, A.; Johnsson, P.; Rading, L.; Siu, W.; Huismans, Y.; Duesterer, S.; Redlin, H.; Tavella, F.; Stojanovic, N.; Al-Shemmary, A.; Lepine, F.; Holland, D. M. P.; Schlathölter, Thomas; Hoekstra, R.; Fukuzawa, H.; Ueda, K.; Vrakking, M. J. J.; Hundertmark, A.

    2013-01-01

    The dissociation dynamics induced by a 100 fs, 400 nm laser pulse in a rotationally cold Br-2 sample was characterized by Coulomb explosion imaging (CEI) using a time-delayed extreme ultra-violet (XUV) FEL pulse, obtained from the Free electron LASer in Hamburg (FLASH). The momentum distribution of

  7. Dispersion relations for 1D high-gain FELs

    International Nuclear Information System (INIS)

    Webb, S.D.; Litvinenko, V.N.

    2010-01-01

    We present analytical results for the one-dimensional dispersion relation for high-gain FELs. Using kappa-n distributions, we obtain analytical relations between the dispersion relations for various order kappa distributions. Since an exact solution exists for the kappa-1 (Lorentzian) distribution, this provides some insight into the number of modes on the way to the Gaussian distribution.

  8. Milestone experiments for single pass UV/X-ray FELs

    Science.gov (United States)

    Ben-Zvi, Ilan

    1995-04-01

    In the past decade, significant advances have been made in the theory and technology of high brightness electron beams and single pass FELs. These developments facilitate the construction of practical UV and X-ray FELs and has prompted proposals to the DOE for the construction of such facilities. There are several important experiments to be performed before committing to the construction of dedicated user facilities. Two experiments are under construction in the IR, the UCLA self-amplified spontaneous emission experiment and the BNL laser seeded harmonic generation experiment. A multi-institution collaboration is being organized about a 210 MeV electron linac available at BNL and the 10 m long NISUS wiggler. This experiment will be done in the UV and will test various experimental aspects of electron beam dynamics, FEL exponential regime with gain guiding, start-up from noise, seeding and harmonic generation. These experiments will advance the state of FEL research and lead towards future dedicated users' facilities.

  9. The FEL-TNO uniform open systems model

    NARCIS (Netherlands)

    Luiijf, H.A.M.; Overbeek, P.L.

    1989-01-01

    The FEL-TNO Uniform Open Systems Model is based upon the IS0/0SI Basic Reference Model and integrates operating systems, (OSI) networks, equipment and media into one single uniform nodel. Usage of the model stimulates the development of operating systen and network independent applications and puts

  10. Optimization Studies of the FERMI at ELETTRA FEL Design

    CERN Document Server

    De Ninno, G

    2005-01-01

    The FERMI at ELETTRA project at Sincotrone Trieste involves two FEL's, each based upon the principle of a seeded harmonic cascade and using the existing ELETTRA injection linac at 1.2 GeV beam energy. Scheduled to be completed in 2008, FEL-1 will operate in the 40-100 nm wavelength range and will involve one stage of harmonic up-conversion. The second phase, FEL-2, will begin operation two years later in the 10-40 nm wavelength range and will involve two cascade stages. FEL design assumes wavelength tunability over the full wavelength range and polarization tunability of the output radiation including helical polarization. The design considers focusing properties and segmentation of realizable undulators and available input seed lasers. We discuss how the interplay between various limitations and self-consistent accelerator simulations [1,2] 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 und...

  11. FELI linac for IR- and UV-FEL facilities

    International Nuclear Information System (INIS)

    Tomimasu, T.; Morii, Y.; Abe, S.

    1995-01-01

    FELI linac and IR-FEL facilities are now under construction and electron beams of 30-75MeV will be used for FIR- and IR-FEL experiments in this summer. It is composed of a 5-MeV electron injector and seven ETL type accelerating waveguides with a length of 2.93m (2π/3 mode, linearly tapered type). The injector consists of a 150-kV DC thermoionic triode gun operated by a 178.5-MHz and 500-ps pulser, a 714-MHz prebuncher (SHB), and a 2856-MHz standing wave type buncher (SWB). The linac is operated in three modes of 24μs, 12.5μs and 0.5μs. With a choice of three modes, the maximum beam loaded energy can be changed from 165 MeV to 288 MeV. The linac beam is sent to four vertical type undulators using S-type BT systems installed at 30-MeV, 75-MeV, 120-MeV, and 165-MeV sections at a 24-μs pulse beam load. The beam, once used for lasing at 30-MeV section or at 75-MeV section, can be bent back to the following accelerating waveguide and is reaccelerated and reused for lasing. Parameters of four undulators and intended FEL applications are shown. FEL spectral widths and wavelength limitations are also reviewed and discussed for 0.3μm FEL oscillations FELI is aiming at by the end of 1996. (author)

  12. Scheme for generation of fully-coherent, TW power level hard X-ray pulses from baseline undulators at the European X-ray FEL

    International Nuclear Information System (INIS)

    Geloni, Gianluca; Kocharyan, Vitali; Saldin, Evgeni

    2010-07-01

    The most promising way to increase the output power of an X-ray FEL (XFEL) is by tapering the magnetic field of the undulator. Also, significant increase in power is achievable by starting the FEL process from a monochromatic seed rather than from noise. This report proposes to make use of a cascade self-seeding scheme with wake monochromators in a tunable-gap baseline undulator at the European XFEL to create a source capable of delivering coherent radiation of unprecedented characteristics at hard X-ray wavelengths. Compared with SASE X-ray FEL parameters, the radiation from the new source has three truly unique aspects: complete longitudinal and transverse coherence, and a peak brightness three orders of magnitude higher than what is presently available at LCLS. Additionally, the new source will generate hard X-ray beam at extraordinary peak (TW) and average (kW) power level. The proposed source can thus revolutionize fields like single biomolecule imaging, inelastic scattering and nuclear resonant scattering. The self-seeding scheme with the wake monochromator is extremely compact, and takes almost no cost and time to be implemented. The upgrade proposed in this paper could take place during the commissioning stage of the European XFEL, opening a vast new range of applications from the very beginning of operations.We present feasibility study and examplifications for the SASE2 line of the European XFEL. (orig.)

  13. The D0 Upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Abachi, S.; D0 Collaboration

    1995-07-01

    In this paper we describe the approved DO Upgrade detector, and its physics capabilities. The DO Upgrade is under construction and will run during the next Fermilab collider running period in early 1999 (Run II). The upgrade is designed to work at the higher luminosities and shorter bunch spacings expected during this run. The major elements of t he upgrade are: a new tracking system with a silicon tracker, scintillating fiber tracker, a 2T solenoid, and a central preshower detector; new calorimeter electronics; new muon trigger and tracking detectors with new muon system electronics; a forward preshower detector; new trigger electronics and DAQ improvements to handle the higher rates.

  14. First experimental data on the FEL - RF interaction at the Jefferson Lab IRFEL

    International Nuclear Information System (INIS)

    L. Merminga; P. Alexeev; S.V. Benson; A. Bolshakov; L.R. Doolittle; D.R. Douglas; C. Hovater; G.R. Neil

    1999-01-01

    High power FELs driven by recirculating, energy-recovering linacs can exhibit instabilities in the beam energy and laser output power. Fluctuations in the accelerating cavity fields can cause beam loss on apertures, phase oscillations and optical cavity detuning. These can affect the laser power and in turn the beam-induced voltage to further enhance the fluctuations of the rf fields. A theoretical model was developed to study the dynamics of the coupled system and was presented last year. Recently, a first set of experimental data was obtained at the Jefferson Lab IRFEL for direct comparisons with the model. The authors describe the experiment, present the data together with the modeling predictions and outline future directions

  15. Field Encapsulation Library The FEL 2.2 User Guide

    Science.gov (United States)

    Moran, Patrick J.; Henze, Chris; Ellsworth, David

    1999-01-01

    This document describes version 2.2 of the Field Encapsulation Library (FEL), a library of mesh and field classes. FEL is a library for programmers - it is a "building block" enabling the rapid development of applications by a user. Since FEL is a library intended for code development, it is essential that enough technical detail be provided so that one can make full use of the code. Providing such detail requires some assumptions with respect to the reader's familiarity with the library implementation language, C++, particularly C++ with templates. We have done our best to make the explanations accessible to those who may not be completely C++ literate. Nevertheless, familiarity with the language will certainly help one's understanding of how and why things work the way they do. One consolation is that the level of understanding essential for using the library is significantly less than the level that one should have in order to modify or extend the library. One more remark on C++ templates: Templates have been a source of both joy and frustration for us. The frustration stems from the lack of mature or complete implementations that one has to work with. Template problems rear their ugly head particularly when porting. When porting C code, successfully compiling to a set of object files typically means that one is almost done. With templated C++ and the current state of the compilers and linkers, generating the object files is often only the beginning of the fun. On the other hand, templates are quite powerful. Used judiciously, templates enable more succinct designs and more efficient code. Templates also help with code maintenance. Designers can avoid creating objects that are the same in many respects, but not exactly the same. For example, FEL fields are templated by node type, thus the code for scalar fields and vector fields is shared. Furthermore, node type templating allows the library user to instantiate fields with data types not provided by the FEL

  16. Altair performance and upgrades

    Science.gov (United States)

    Lai, Olivier; Véran, Jean-Pierre; Herriot, Glen; White, John; Ball, Jesse; Trujillo, Chad

    2014-07-01

    Altair is the facility single conjugate AO system for Gemini North. Although it has been in operation for more than 10 years (and upgraded to LGS in 2007), Altair's performance is degraded by three main issues: vibrations of the telescope and instrument support structure, spatial aliasing on centroid offsets from the M2 support structure print-through on the optical surface and static non-common path aberrations. Monte-Carlo simulations can reproduce the behavior of Altair when including these three effects and they are roughly of the same order of magnitude. Solutions or mitigations are being investigated to overcome these nefarious effects and restore Altair's performance to its nominal level. A simplex algorithm as well as a phase diversity approach are being investigated to measure and correct for static aberrations. A high accuracy phase map of the M2 print-through has been obtained and is being used to calibrate and/or filter centroids affected by aliasing. A new real time computer is under consideration, to be able to handle more advanced controllers, especially notch filters to combat vibrations. In this paper we will report on the various simulations and on-sky results of this rejuvenation of one of Gemini's workhorse instruments.

  17. Cavity-mirror degradation in the deep-UV FEL

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, K.; Yamazaki, T.; Sei, N. [Electrotechnical Lab., Ibaraki (Japan)] [and others

    1995-12-31

    It is known that the degradation of dielectric multilayer mirrors used in short wavelength free-electron lasers (FELs) is caused by the carbon contamination on the mirror surface and the defects inside the dielectrics. We reported last year that the degraded dielectric multilayer mirrors can be repaired with both surface treatment by RF-induced oxygen plasma and thermal annealing. However, such a mirror degradation is still one of the most critical issues in the deep ultraviolet (UV) FELs, because the fundamental undulator radiation resonating in the laser cavity, the intensity of which is much higher than that of higher harmonics, can be sufficiently energetic to cause the mirror degradation through photochemical reactions. We are investigating the mirror degradation mainly in the deep UV region down to 240 nm. The experimental results will be shown. The mirror degradation mechanism will be discussed.

  18. A wiggler magnet for FEL low voltage operation

    Energy Technology Data Exchange (ETDEWEB)

    Al-Shamma`a, A.; Stuart, R.A.; Lucas, J.

    1995-12-31

    In low voltage FELs (ie, 200kV), operation is necessarily in the microwave frequency range for wiggler periods of the order of cms., so that a waveguide system is mandatory. Also, because of the relatively low velocity of the electron beam, the wiggle amplitude of the electron beam can be much larger than is normal for highly relativistic FELs. Both these factors mean that the electron trajectory must be carefully controlled to avoid beam collision with the waveguide walls. A wiggler system with half poles at entrance and exit is not an acceptable solution because of the offset is gives rise to the electron trajectory. Consequently, we have designed and constructed a wiggler magnet with exponential entrance and exit tapers for a minimal deflection and displacement of the electron beam. Simulations and experimental measurements showed that an on axis trajectory is easily obtainable.

  19. Energy stability in a high average power FEL

    International Nuclear Information System (INIS)

    Mermings, L.; Bisognano, J.; Delayen, J.

    1995-01-01

    Recirculating, energy-recovering linacs can be used as driver accelerators for high power FELs. Instabilities which arise from fluctuations of the cavity fields or beam current are investigated. Energy changes can cause beam loss on apertures, or, when coupled to M, phase oscillations. Both effects change the beam induced voltage in the cavities and can lead to unstable variations of the accelerating field. Stability analysis for small perturbations from equilibrium is performed and threshold currents are determined. Furthermore, the analytical model is extended to include feedback. Comparison with simulation results derived from direct integration of the equations of motion is presented. Design strategies to increase the instability threshold are discussed and the UV Demo FEL, proposed for construction at CEBAF, and the INP Recuperatron at Novosibirsk are used as examples

  20. Feedback Control Of Dynamical Instabilities In Classical Lasers And Fels

    CERN Document Server

    Bielawski, S; Szwaj, C

    2005-01-01

    Dynamical instabilities lead to unwanted full-scale power oscillations in many classical lasers and FEL oscillators. For a long time, applications requiring stable operation were typically performed by working outside the problematic parameter regions. A breakthrough occurred in the nineties [1], when emphasis was made on the practical importance of unstable states (stationary or periodic) that coexist with unwanted oscillatory states. Indeed, although not observable in usual experiments, unstable states can be stabilized, using a feedback control involving arbitrarily small perturbations of a parameter. This observation stimulated a set of works leading to successful suppression of dynamical instabilities (initially chaos) in lasers, sometimes with surprisingly simple feedback devices [2]. We will review a set of key results, including in particular the recent works on the stabilization of mode-locked lasers, and of the super-ACO, ELETTRA and UVSOR FELs [3].

  1. Help system for control of JAERI FEL (Free Electron laser)

    International Nuclear Information System (INIS)

    Sugimoto, Masayoshi

    1993-01-01

    The control system of JAERI FEL (Free Electron Laser) has a help system to provide the information necessary to operate the machine and to develop the new user interface. As the control software is constructed on the MS-Windows 3.x, the hyper-text feature of the Windows help system can be accessed. It consists of three major parts: (1) on-line help, (2) full document, and (3) tutorial system. (author)

  2. Upgrading uncompetitive products economically

    DEFF Research Database (Denmark)

    Lu, Hua; Jensen, Christian Søndergaard

    2012-01-01

    for upgrading an uncompetitive product, and combine the solutions into a single solution. We also propose a spatial join-based solution that assumes P and T are indexed by an R-tree. Given a set of products in the same R-tree node, we derive three lower bounds on their upgrading costs. These bounds are employed...

  3. Maintenance procedure upgrade programs

    International Nuclear Information System (INIS)

    Campbell, J.J.; Zimmerman, C.M.

    1988-01-01

    This paper describes a systematic approach to upgrading nuclear power plant maintenance procedures. The approach consists of four phases: diagnosis, program planning, program implementation, and program evaluation. Each phase is explained as a series of steps to ensure that all factors in a procedure upgrade program are considered

  4. The JAERI superconducting RF linac-based FELS and THEIR cryogenics

    International Nuclear Information System (INIS)

    Minehara, Eisuke J.

    2003-01-01

    In the 21st century, we need a powerful and efficient free-electron laser (FEL) for academic and industrial uses in almost all fields. In order to realize such a tunable, highly-efficient, high average power, high peak power and ultra-short pulse FEL, the JAERI FEL group and I have developed an industrial FEL driven by a compact, stand-alone and zero-boil off super-conducting rf linac with an energy-recovery geometry. Our discussions on the JAERI FEL and cryogenics will cover market-requirements for the industrial FELs, some answers from the JAERI compact, stand-alone and zero-boil off cryostat concept and operational experiences over these 9 years, our discovery of the new, highly-efficient, high-power, and ultra-short pulse lasing mode, and the energy-recovery geometry. (author)

  5. Pulsed power supply for Nova Upgrade

    International Nuclear Information System (INIS)

    Bacon, J.L.; Kajs, J.P.; Walls, A.; Weldon, W.F.; Zowarka, R.C.

    1992-01-01

    This report describes work carried out at the Center for Electromechanics at The University of Texas at Austin (CEM-UT). A baseline design of the Nova Upgrade has been completed by Lawrence Livermore National Laboratory. The Nova Upgrade is an 18 beamline Nd: glass laser design utilizing fully relayed 4x4 30 cm aperture segmented optical components. The laser thus consists of 288 independent beamlets nominally producing 1.5 to 2.0 MJ of 0.35 μm light in a 3 to 5 ns pulse. The laser design is extremely flexible and will allow a wide range of pulses to irradiate ICF targets. This facility will demonstrate ignition/gain and the scientific feasibility of ICF for energy and defense applications. The pulsed power requirements for the Nova Upgrade are given. CEM-UT was contracted to study and develop a design for a homopolar generator/inductor (HPG/inductor) opening switch system which would satisfy the pulsed power supply requirements of the Nova Upgrade. The Nd:glass laser amplifiers used in the Nova Upgrade will be powered by light from xenon flashlamps. The pulsed power supply for the Nova Upgrade powers the xenon flashlamps. This design and study was for a power supply to drive flashlamps

  6. Seeded quantum FEL at 478 keV

    Energy Technology Data Exchange (ETDEWEB)

    Guenther, Marc [Max-Planck-Institut fuer Quantenoptik, Garching (Germany); Thirolf, Peter; Seggebrock, Thorben [Ludwig-Maximilians-Universitaet Muenchen, Garching (Germany); Habs, Dietrich [Max-Planck-Institut fuer Quantenoptik, Garching (Germany); Ludwig-Maximilians-Universitaet Muenchen, Garching (Germany)

    2012-07-01

    We present for the first time a concept for a seeded {gamma} quantum Free Electron Laser (QFEL) at 478 keV (transition in {sup 7}Li). To produce a highly intense and coherent {gamma} beam, we intend to use a seeded FEL scheme. Important for the production of a highly brilliant and coherent {gamma} beam are novel refractive {gamma} lenses for focusing and an efficient monochromator, allowing to generate a very intense and coherent seed beam. To realize such a coherent {gamma} beam at 478 keV (1/38 A), it is suitable to use a quantum FEL design based on a new ''asymmetric'' laser-electron Compton back scattering scheme as pursued for the MeGaRay and ELI-NP facilities. Here the pulse length of the laser is much longer than the electron bunch length, equivalent to a {gamma}-FEL with laser wiggler. The coherence of a seeded QFEL can open up totally new areas of fundamental physics and applications. Especially, 478 keV can be attractive for ''green energy'' and life-science research, such as the detection of Li deposition in the brain for manic-depressive psychosis treatment with high spatial resolution or isotope-specific nuclear waste management and treatment.

  7. NSLS control system upgrade

    International Nuclear Information System (INIS)

    Smith, J.D.; Ramamoorthy, Susila; Tang, Y.N.

    1994-01-01

    The NSLS consists of two storage rings, a booster and a linac. A major upgrade of the control system (installed in 1978) was undertaken and has been completed. The computer architecture is being changed from a three level star-network to a two level distributed system. The microprocessor subsystem, host computer and workstations, communication link and the main software components are being upgraded or replaced. Since the NSLS rings operate twenty four hours a day a year with minimum maintenance time, the key requirement during the upgrade phase is a non-disruptive transition with minimum downtime. Concurrent with the upgrade, some immediate improvements were required. This paper describes the various components of the upgraded system and outlines the future plans. ((orig.))

  8. NSLS control system upgrade

    International Nuclear Information System (INIS)

    Smith, J.D.; Ramamoorthy, S.; Tang, Yong N.

    1995-01-01

    The NSLS consists of two storage rings, a booster and a linac. A major upgrade of the control system (installed in 1978) was undertaken and has been completed. The computer architecture is being changed from a three level star-network to a two level distributed system. The microprocessor subsystem, host computer and workstations, communication link and the main software components are being upgraded or replaced. Since the NSLS rings operate twenty four hours a day a year with minimum maintenance time, the key requirement during the upgrade phase is a non-disruptive transition with minimum downtime. Concurrent with the upgrade, some immediate improvements were required. This paper describes the various components of the upgraded system and outlines the future plans

  9. To upgrade or not to upgrade

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn; Rose, Jørgen

    2017-01-01

    This paper identifies the key indicators that owners need to take into account in order to choose the most affordable extent of upgrading of a typical post-1945 building. The exterior look of the building is not to be changed. Indicators include measures, risk assessment related to the changes in...

  10. A study of phase control in the FEL [free electron laser] two-beam accelerator

    International Nuclear Information System (INIS)

    Sessler, A.M.; Whittum, D.H.; Wurtele, J.S.

    1989-08-01

    A formalism is developed for the analysis of a steady-state free electron laser (FEL) and is applied to the two-beam accelerator (TBA). Conditions are derived for the design of a FEL TBA with rf output power and phase insensitive to errors in both beam current and energy. An example is presented of a suitably phase insensitive TBA design with 100 reaccelerations employing untapered FEL sections and with low power rf input to each section. The theoretical analysis is confirmed by a single particle FEL simulations. 9 refs., 2 tabs

  11. Upgrading during difficult times

    International Nuclear Information System (INIS)

    Tiefenbach, K.

    1993-01-01

    The Co-op Upgrader is part of an integrated refinery and upgrader complex in Regina, Saskatchewan. The upgrader processes 50,000 bbl/d heavy sour crude oil, mostly Fosterton and dilute Lloydminster crude, via hydrogen addition and carbon rejection, desulfurization, demetallization, and denitrification to yield a synthetic crude blend. The synthetic crude is refined to produce gasoline and diesel fuel. Byproducts from the integrated operation include 100,000 tonnes/y of petroleum coke, 65,000 tonnes/y of sulfur, propane, butane, fuel oil, and metals (Ni and V) in the form of spent catalysts. Recent operational and economic challenges faced by the upgrader are reviewed. Technical challenges include operating the upgrader's high-temperature high-pressure heavy oil hydrotreating unit and distillate hydrogenation unit, removal and replacement of the desulfurization catalyst, waste management, and producing coke of sufficient quality. Economic challenges include the shrinking differential between light and heavy oil, higher prices for natural gas (the main raw material for hydrogen production for upgrading), seasonal changes in product specifications, and lower prices for sulfur and metal byproducts. The upgrader is also affected by interest rates since borrowing costs are the single largest expenditure after crude oil purchases. 4 figs

  12. R and D Requirements, RF Gun Mode Studies, FEL-2 Steady-State Studies, Preliminary FEL-1 Time-Dependent Studies, and Preliminary Layout Option Investigation

    International Nuclear Information System (INIS)

    Byrd, John; Corlett, John; Doolittle, Larry; Fawley, William; Lidia, Steven; Penn, Gregory; Ratti, Alex; Staples, John; Wilcox Russell; Wurtele, Jonathan; Zholents, Alexander

    2005-01-01

    This report constitutes the third deliverable of LBNLs contracted role in the FERMI (at) Elettra Technical Optimization study. It describes proposed RandD activities for the baseline design of the Technical Optimization Study, initial studies of the RF gun mode-coupling and potential effects on beam dynamics, steady-state studies of FEL-2 performance to 10 nm, preliminary studies of time-dependent FEL-1 performance using electron bunch distribution from the start-to-end studies, and a preliminary investigation of a configuration with FEL sinclined at a small angle from the line of the linac

  13. The LHCb Muon Upgrade

    CERN Multimedia

    Cardini, A

    2013-01-01

    The LHCb collaboration is currently working on the upgrade of the experiment to allow, after 2018, an efficient data collection while running at an instantaneous luminosity of 2x10$^{33}$/cm$^{-2}$s$^{-1}$. The upgrade will allow 40 MHz detector readout, and events will be selected by means of a very flexible software-based trigger. The muon system will be upgraded in two phases. In the first phase, the off-detector readout electronics will be redesigned to allow complete event readout at 40 MHz. Also, part of the channel logical-ORs, used to reduce the total readout channel count, will be removed to reduce dead-time in critical regions. In a second phase, higher-granularity detectors will replace the ones installed in highly irradiated regions, to guarantee efficient muon system performances in the upgrade data taking conditions.

  14. Bi-Provincial Upgrader

    International Nuclear Information System (INIS)

    1997-01-01

    Husky Oil's Bi-Provincial Upgrader is located in the rural municipality of Wilton, east of Lloydminster, Saskatchewan. It is jointly owned by Husky Oil and the Saskatchewan government. The upgrader is designed to produce 7.300 m 3 /cd of synthetic crude from 8.440 m 3 /cd of diluted Lloyd blend and distillates from the existing Lloydminster refinery. The designed coke and sulphur production is 415 t/day and 240 t/day respectively. Chronology of the Bi-Provincial Upgrader project was presented, along with details of the heavy oil feedstock properties for Cold Lake, Lloydminster and Lloyd Blend. Upgrader production history since start-up, synthetic crude oil customers, and the evolution of prices for Edmonton light vs. Husky LLB at Hardisty were also reviewed. 3 tabs., 9 figs

  15. LEP is upgraded

    CERN Multimedia

    1995-01-01

    A superconducting radio-frequency cavity is installed on the Large Electron-Positron (LEP) collider. This upgrade, known as LEP-2, allowed the accelerator to reach new, higher energies and so investigate new areas of physics.

  16. Linac-beam characterizations at 600 MeV using optical transition radiation diagnostics.

    Energy Technology Data Exchange (ETDEWEB)

    Lumpkin, A. H.

    1998-05-27

    Selected optical diagnostics stations were upgraded in anticipation of low-emittance, bright electron beams from a thermionic rf gun or a photoelectric rf gun on the Advanced Photon Source (APS) injector linac. These upgrades include installation of optical transition radiation (OTR) screens, transport lines, and cameras for use in transverse beam size measurements and longitudinal profile measurements. Using beam from the standard thermionic gun, tests were done at 50 MeV and 400 to 650 MeV. Data were obtained on the limiting spatial ({sigma} {approximately} 200 {micro}m) and temporal resolution (300 ms) of the Chromox (Al{sub 2}O{sub 3} : Cr) screen (250-{micro}n thick) in comparison to the OTR screens. Both charge-coupled device (CCD) and charge-injection device (CID) video cameras were used as well as the Hamamatsu C5680 synchroscan streak camera operating at a vertical deflection rate of 119.0 MHz (the 24th subharmonic of the S-band 2856-MHz frequency). Beam transverse sizes as small as {sigma}{sub x} = 60 {micro}m for a 600-MeV beam and micropulse bunch lengths of {sigma}{sub {tau}}<3 ps have been recorded for macropulse-averaged behavior with charges of about 2 to 3 nC per macropulse. These techniques are applicable to linac-driven, fourth-generation light source R and D experiments including the APS's SASE FEL experiment.

  17. Nonlinear optics with coherent free electron lasers

    Science.gov (United States)

    Bencivenga, F.; Capotondi, F.; Mincigrucci, R.; Cucini, R.; Manfredda, M.; Pedersoli, E.; Principi, E.; Simoncig, A.; Masciovecchio, C.

    2016-12-01

    We interpreted the recent construction of free electron laser (FELs) facilities worldwide as an unprecedented opportunity to bring concepts and methods from the scientific community working with optical lasers into the domain of x-ray science. This motivated our efforts towards the realization of FEL-based wave-mixing applications. In this article we present new extreme ultraviolet transient grating (X-TG) data from vitreous SiO2, collected using two crossed FEL pulses (photon frequency 38 eV) to generate the X-TG and a phase matched optical probing pulse (photon frequency 3.1 eV). This experiment extends our previous investigation, which was carried out on a nominally identical sample using a different FEL photon frequency (45 eV) to excite the X-TG. The present data are featured by a peak intensity of the X-TG signal substantially larger than that previously reported and by slower modulations of the X-TG signal at positive delays. These differences could be ascribed to the different FEL photon energy used in the two experiments or to differences in the sample properties. A systematic X-TG study on the same sample as a function of the FEL wavelength is needed to draw a consistent conclusion. We also discuss how the advances in the performance of the FELs, in terms of generation of fully coherent photon pulses and multi-color FEL emission, may push the development of original experimental strategies to study matter at the femtosecond-nanometer time-length scales, with the unique option of element and chemical state specificity. This would allow the development of advanced experimental tools based on wave-mixing processes, which may have a tremendous impact in the study of a large array of phenomena, ranging from nano-dynamics in complex materials to charge and energy transfer processes.

  18. Parametric x-ray FEL operating with external Bragg reflectors

    International Nuclear Information System (INIS)

    Baryshevsky, V.G.; Batrakov, K.G.; Dubovskaya, I.Ya.

    1995-01-01

    In the crystal X-ray FELs using channeling and parametric quasi-Cherenkov mechanisms of spontaneous radiation were considered as versions of FEL allowing, in principle, to obtain coherent X-ray source. In this case a crystal is both radiator and resonator for X-rays emitted by a particle beam passing through crystal. However, it is well-known that a beam current density required for lasing is extremely high in X-ray spectral range for any radiation mechanisms and it is very important to find a way to lower its magnitude. The application of three-dimensional distributed feedback formed by dynamical diffraction of emitted photons permitted to reduce starting beam current density 10 2 -10 4 times up to 10 9 . One of ways to lower the starting current is the formation of multi-wave distributed feedback the another one is the application of external reflectors. The thing is that lasing regime was shown to be produced at frequencies in the vicinity of degeneration point for roots of dispersion equation describing radiation modes excited in an active medium (crystal plus particle beam). Unfortunately, in case of parametric quasi-Cherenkov FEL this region coincides with the region of strong self-absorption of radiation inside a crystal. That fact, obviously, increases the starting beam current. In this report we have shown that the application of external Bragg reflectors gives the possibility to lower radiation self-absorption inside a crystal by modifying radiation modes excited in the active medium under consideration. The corresponding dispersion equation and the expression for excited modes are derived. The generation equation determining starting conditions for lasing is obtained. Using these expressions we have shown that the application of external Bragg reflectors permits to reduce starting beam current density more than 10 times

  19. Theoretical analysis of experimental results on SG-1 FEL

    International Nuclear Information System (INIS)

    Yang Zhenhua; Wu Shangqing; Tian Shihong; Dong Zhiwei; Wu Yupu

    1994-01-01

    In order to study the SG-1 FEL and the beam transport thoroughly, and draw certain quantitative conclusions, we developed 3-D WAGFEL code to describe the FEL evolution and 3-D CEBQ code to describe the beam transport. The CEBQ code can simulate the 3-D transport of the electron beam in the modulation section with linear approximation of space charge. According to the first ASE experiments results, the LIA provided a 2 kA, 3.0 MeV beam with a normalized emittance of 0.6 πrad·cm, an energy spread (FWHM) of 4%, resulting in a beam brightness nearly 10 8 A/(πm·rad) 2 . The numerical simulation showed that the quality of the beam was good enough to abandon the 9-m long beam line and substitute it with a 2-m long drifting and focusing region. The second series of ASE and amplifier experiments began in October 1992. The beam transport section was modified. The ASE output power, the amplifier output power and detuning curve was measured. We analysed the experimental results using the WAGFEL and CEBQ codes with parameters equal to those of experiments. Firstly we followed 4096 electrons to simulate the transport process of the beam in the beam line under the condition of I = 2 kA, r b = 1 cm, γ = 6.8, Δγ/γ 4%, ε rms = 0.6 (πrad·cm). Through the simulation, we predicted that the beam current injected into the wiggler was about 611 A. Based on these beam parameters at the entrance of the wiggler, we simulated the FEL process with P in = 300 W. The results are also in Fig.7,8,9

  20. Wavelength dependent delay in the onset of FEL tissue ablation

    International Nuclear Information System (INIS)

    Tribble, J.A.; Edwards, G.S.; Lamb, J.A.

    1995-01-01

    We are investigating the wavelength dependence of the onset of laser tissue ablation in the IR Visible and UV ranges. Toward this end, we have made simultaneous measurements of the ejected material (using a HeNe probe beam tangential to the front surface) and the residual stress transient in the tissue (using traditional piezoelectric detection behind the thin samples). For the IR studies we have used the Vanderbilt FEL and for the UV and Vis range we have used a Q-switched ND:Yag with frequency doubling and quadrupling. To satisfy the conditions of the near field limit for the detection of the stress transient, the duration of the IR FEL macropulse must be as short as possible. We have obtained macropulses as short as 100 ns using Pockels Cell technology. The recording of the signals from both the photodiode monitoring the HeNe probe beam and the acoustic detector are synchronized with the arrival of the 100 ns macropulse. With subablative intensities, the resulting stress transient is bipolar with its positive peak separated from its negative peak by 100 ns in agreement with theory. Of particular interest is the comparison of ablative results using 3 μm and 6.45 μm pulses. Both the stress transient and the ejection of material suffer a greater delay (with respect to the arrival of the 100 ns pulse) when the FEL is tuned to 3 μm as compared to 6.45 μm. A comparison of IR Vis and UV data will be discussed in terms of microscopic mechanisms governing the laser ablation process

  1. Real time diagnostic for operation at a CW low voltage FEL

    Energy Technology Data Exchange (ETDEWEB)

    Balfour, C.; Shaw, A.; Mayhew, S.E. [and others

    1995-12-31

    At Liverpool University, a system for single user control of an FEL has been designed to satisfy the low voltage FEL (ie 200kV) operational requirements. This system incorporates many aspects of computer automation for beam diagnostics, radiation detection and vacuum system management. In this paper the results of the development of safety critical control systems critical control systems are reported.

  2. A single-particle calculation of the FEL-Cerenkov gain

    International Nuclear Information System (INIS)

    Dattoli, G.; Doria, A.; Gallerano, G.P.; Renieri, A.; Schettini, G.; Torre, A.

    1988-01-01

    In this work it is shown that the basic FEL-Cerenkov dynamics can be modelled using a pendulumlike equation in close analogy with FEL undulator case. The analysis, including the inhomogeneous broadening effects, is worked out in the hypothesis of single-slab geometry. Two-dimensional motion dynamics effects are also included

  3. On FEL integral equation and electron energy loss in intermediate gain regime

    International Nuclear Information System (INIS)

    Takao, Masaru

    1994-03-01

    The FEL pendulum equation in a intermediate gain small signal regime is investigated. By calculating the energy loss of the electron beam in terms of the solution of the pendulum equation, we confirm the consistency of the FEL equation in intermediate gain regime. (author)

  4. Towards attosecond X-ray pulses from the FEL

    International Nuclear Information System (INIS)

    Zholents, Alexander A.; Fawley, William M.

    2004-01-01

    The ability to study ultrafast phenomena has been recently advanced by the demonstrated production and measurement of a single, 650-attosecond (10 18 sec), VUV x-ray pulse[1] and, latter, a 250-attosecond pulse[2]. The next frontier is a production of the x-ray pulses with shorter wavelengths and in a broader spectral range. Several techniques for a generation of an isolated, attosecond duration, short-wavelength x-ray pulse based upon the ponderomotive laser acceleration [3], SASE and harmonic cascade FELs ([4] - [6]) had been already proposed. In this paper we briefly review a technique proposed in [5] and present some new results

  5. Lattice design for a high-power infrared FEL

    International Nuclear Information System (INIS)

    Douglas, D.R.

    1997-01-01

    A 1 kW infrared FEL, funded by the U.S. Navy, is being built at Jefferson Lab. It will be driven by a compact energy-recovering CW superconducting radio-frequency (SRF)-based linear accelerator. Stringent phase space requirements at the wiggler, low beam energy, and high beam current subject the design to numerous constraints. This report addresses these issues and presents a design solution for an accelerator transport lattice meeting the requirements imposed by physical phenomena and operational necessities

  6. Characteristics of the FEL project for the MUH experiment

    International Nuclear Information System (INIS)

    Ciocci, F.; Doria, A.; Fascetti, M.; Gallerano, G.P.; Giannessi, L.; Giovenale, E.; Messina, G.; Picardi, L.; Renieri, A.; Ronci, G.; Ronsivalle, C.; Vignati, A.

    1999-01-01

    The design characteristics of a compact Free Electron Laser (FEL) operating in the far infrared spectral range between 200 and 600 μm are presented in this report. The device can be employed in a fundamental physics experiment to be performed in collaboration with INFN-Trieste and the Paul Sherrer Institute- Villigen. Spectroscopic measurements in the above spectral region will allow one to determine the energy difference between the levels 3D-3P in the μP system with great accuracy [it

  7. Electron beam acceleration and compression for short wavelength FELs

    International Nuclear Information System (INIS)

    Raubenheimer, T.O.

    1994-11-01

    A single pass UV or X-ray FEL will require a low emittance electron beam with high peak current and relatively high beam energy, a few hundred MeV to many GeV. To achieve the necessary peak current and beam energy, the beams must be bunch compressed and they must be accelerated in long transport lines where dispersive and wakefield emittance dilutions are important. In this paper, we will describe the sources and significance of the dilutions during acceleration, bunch compression, and transport through the undulator. In addition, we will discuss sources of jitter, especially effects arising from the bunch compressions, and the possible cancellation techniques

  8. X-ray beam splitting design for concurrent imaging at hard X-ray FELs and synchrotron facilities

    Energy Technology Data Exchange (ETDEWEB)

    Oberta, P., E-mail: peter.oberta@rigaku.com [Institute of Physics, Academy of Sciences of the Czech Republic, v.v.i., Na Slovance 2, Praha 8, CZ-18221 (Czech Republic); Rigaku, Novodvorská 994, Praha 4, CZ-14221 (Czech Republic); Mokso, R. [Swiss Light Source, Paul Scherrer Institut, Villigen, CH-5232 Villigen (Switzerland)

    2013-11-21

    A new configuration of diffractive–refractive optics for beam splitting is investigated. The set-up can be applied to perform imaging with two beams simultaneously. It brings advantages toward dynamic studies using image guided diffraction or fluorescence spectroscopy. The optimal energy range of operation for the beam-splitter is between 7 keV and 24 keV, reaching best efficiency at an energy of 10 keV. Due to the long focusing distances (several tens of meters) created by the diffractive–refractive optics and the higher refraction efficiency in the softer energy range, the presented set-ups are ideal for hard X-ray FEL sources.

  9. Formaldehyde OMI operational retrieval upgrades

    Science.gov (United States)

    Gonzalez Abad, G.; Chance, K.; Liu, X.

    2013-05-01

    Total column of formaldehyde (HCHO), a proxy for biogenic emissions, can be observed from satellites using the ultraviolet region of the spectrum. The operational HCHO retrievals from the Ozone Monitoring Instrument (OMI) on board the AURA satellite, part of NASA's A-train constellation of Earth Observing satellites, are described. The operational retrieval, based on a basic optical absorption spectroscopy (BOAS) algorithm, has been affected by the degradation of the instrument especially from 2008 onwards. The most significant problems are the unrealistic increasing high background concentrations of HCHO retrieved from OMI and the row anomaly. An upgrade for the original operational algorithm is therefore needed to ensure its trend quality and to account for these difficulties. The strategies implemented to deal with the instrumental degradation are presented here. Air mass factors (AMFs) in the current fitting window show significant wavelength dependence. Fitting uncertainties can potentially be improved by including shorter wavelengths as long as the AMFs wavelength dependence is taken into account. As part of these improvements a look-up table of wavelength-dependent AMFs have been calculated. Using this new table it is possible to retrieve the HCHO total column directly, weighting the HCHO cross sections with the wavelength-dependent AMFs. Additionally, the pixels affected by the row anomaly are now flagged in the level 2 data generated with the upgraded algorithm.

  10. Dynamical behaviour of FEL devices operating with two undulators having opposite circular polarizations

    Energy Technology Data Exchange (ETDEWEB)

    Dattoli, G. [ENEA, Divisione Fisica Applicata, Centro Ricerche Frascati, Rome (Italy); Ottaviani, P.L. [ENEA, Divisione Fisica Applicata, Centro Ricerche, Bologna (Italy); Bucci, L. [ENEA, Guest Rome (Italy)

    2000-07-01

    Optical-Klystron FELs operating with undulators having opposite circular polarizations are characterized by a spontaneous emission spectrum which does not exhibit the characteristic interference pattern. The use of the Madey theorem may allow the conclusion that, for such configuration, the dispersive section does not provide any gain enhancement. In this paper it has been analyzed the problem from a dynamical point of view and clarify how the optical field evolve, what is the role of the bunching and how the consequences of the Madey theorem should be correctly understood. [Italian] Klystron ottici operanti con ondulatori aventi polarizzazione elicoidali opposte, sono caratterizzati da uno spettro di emissione spontanea senza il termine interferenziale dovuto alla sezione dispersiva. L'uso del teorema di Madey indurrebbe alla conclusione che, per una tale configurazione, la sezione dispersiva non induce nessun aumento del guadagno. In questo lavoro analizziamo il problema da un punto di vista dinamico che chiarisce l'evoluzione del campo ottico, quale e' il ruolo del bunching e come le conseguenze del teorema di Madey debbano essere interpretate.

  11. Picked FEL Micro Pulse for Nano-Second Interaction with Bio-Molecule

    CERN Document Server

    Suzuki, Sachiko; Ishii, Katsonuri; Kanai, T; Naito, Y

    2004-01-01

    Laser pulse duration is a very important parameter to determine the threshold between thermal and nonthermal effects in laser surgery of biomedical tissue. Free Electron Laser (FEL) at Osaka University, Japan, has a pulse structure in which a macropulse (pulse width : 15μs) consists of equally separated micropulses, whose width and interval are ~5ps and 44.8ns, respectively. Precise control of micropulse train may establish fast optic processes because thermal relaxation time in the tissue is about 1us. A pulse-picking system was designed in order to extract single or a few micropulses from an entire macropulse using an acousto-optic modulator (AOM) in which the light path can be temporally diffracted by an external gate signal. An extracted micropulse train was monitored by a mercury-cadmium-telluride (MCT) photodetector with ~1ns response time and recorded on digital oscilloscope. A single micropulse was extracted as a result of adjusting duration of the RF wave to 50 ns which is nearly equal to the ...

  12. Split-And-Delay Unit for FEL Interferometry in the XUV Spectral Range

    Directory of Open Access Journals (Sweden)

    Sergey Usenko

    2017-05-01

    Full Text Available In this work we present a reflective split-and-delay unit (SDU developed for interferometric time-resolved experiments utilizing an (extreme ultraviolet XUV pump–XUV probe scheme with focused free-electron laser beams. The developed SDU overcomes limitations for phase-resolved measurements inherent to conventional two-element split mirrors by a special design using two reflective lamellar gratings. The gratings produce a high-contrast interference signal controlled by the grating displacement in every diffraction order. The orders are separated in the focal plane of the focusing optics, which enables one to avoid phase averaging by spatially selective detection of a single interference state of the two light fields. Interferometry requires a precise relative phase control of the light fields, which presents a challenge at short wavelengths. In our setup the phase delay is determined by an in-vacuum white light interferometer (WLI that monitors the surface profile of the SDU in real time and thus measures the delay for each laser shot. The precision of the WLI is 1 nm as determined by optical laser interferometry. In the presented experimental geometry it corresponds to a time delay accuracy of 3 as, which enables phase-resolved XUV pump–XUV probe experiments at free-electron laser (FEL repetition rates up to 60 Hz.

  13. The ALICE TPC Upgrad

    Science.gov (United States)

    Castro, Andrew; Alice-Usa Collaboration; Alice-Tpc Collaboration

    2017-09-01

    The Time Projection Chamber (TPC) currently used for ALICE (A Large Ion Collider Experiment at CERN) is a gaseous tracking detector used to study both proton-proton and heavy-ion collisions at the Large Hadron Collider (LHC) In order to accommodate the higher luminosit collisions planned for the LHC Run-3 starting in 2021, the ALICE-TPC will undergo a major upgrade during the next LHC shut down. The TPC is limited to a read out of 1000 Hz in minimum bias events due to the intrinsic dead time associated with back ion flow in the multi wire proportional chambers (MWPC) in the TPC. The TPC upgrade will handle the increase in event readout to 50 kHz for heavy ion minimum bias triggered events expected with the Run-3 luminosity by switching the MWPCs to a stack of four Gaseous Electron Multiplier (GEM) foils. The GEM layers will combine different hole pitches to reduce the dead time while maintaining the current spatial and energy resolution of the existing TPC. Undertaking the upgrade of the TPC represents a massive endeavor in terms of design, production, construction, quality assurance, and installation, thus the upgrade is coordinated over a number of institutes worldwide. The talk will go over the physics motivation for the upgrade, the ALICE-USA contribution to the construction of Inner Read Out Chambers IROCs, and QA from the first chambers built in the U.S

  14. Advanced Electron Beam Diagnostics for the FERMI FEL

    CERN Document Server

    Ferianis, M; D'Auria, G; Di Mitri, S

    2005-01-01

    Fermi is the fourth generation light source currently under design at ELETTRA: based on the Harmonic Generation (HG) scheme it will generate FEL radiation in the 100-10nm range. The successful implementation of the HG scheme calls also for precise knowledge of electron beam emittances and energy spread as well as for very accurate control on the photon to electron interaction, in the Undulator sections. In this paper we present our design for two fundamental Diagnostics foreseen for the new FERMI LINAC: the Beam Position Monitors (BPM) and the Transverse Deflecting cavity set-up. Sensitivity studies on transverse beam displacement effects on global stability of FEL output radiation dictate the ultimate performance to be provided by the BPM system. Due to non negligible longitudinal occupancy of a cavity type BPM, some efforts have been put to study compact cavity BPM configuration. A proper set-up of RF deflecting cavity combined with the vertical ramp foreseen at the end of the LINAC provide a powerful tool ...

  15. Options for the Cryogenic System for the BESSY-FEL

    International Nuclear Information System (INIS)

    Kutzschbach, A.; Quack, H.; Haberstroh, Ch.; Knobloch, J.; Anders, W.; Pflueckhahn, D.

    2004-01-01

    The Berliner Elektronenspeicherring-Gesellschaft fuer Synchrotronstrahlung (BESSY GmbH), in January 1999, started operation of BESSY II, a third-generation synchrotron light source delivering world-class, high-brilliance photon beams in the VUV to XUV spectral range. Based on this experience, BESSY has recently proposed the construction of a free-electron laser (FEL), covering a photon-energy range from 20 eV to 1 keV.To reduce the development time and cost, BESSY intends to use proven cavity and cryostat technology developed for the TESLA linear collider. However, the cryogenic load per cavity is approximately 15 to 20 times higher than that anticipated for the (pulsed) TESLA operation. This paper describes possible modifications of the cryostat design to accommodate these additional losses.Superconducting RF cavities are the basis of the FEL accelerator providing the driving electron beam with 2.25 GeV. The accelerator consists of five cold sections separated by warm sections reserved for bunch compression and beam extraction. The total refrigeration load will be covered by a single refrigerator. Several possible layouts of the cryogenic system are described and their advantages and disadvantages are discussed

  16. ATLAS Upgrade Programme

    CERN Document Server

    Hillier, S J; The ATLAS collaboration

    2012-01-01

    With the already outstanding LHC luminosity performance, and planned LHC upgrades in the upcoming shutdowns, it is expected that within a short time-scale, the general purpose LHC experiments will have to cope with luminosities beyond their original design. In order to maintain detector performance and sensitivity to expected and new physics processes, ATLAS has defined a continuous upgrade programme which foresees staged enhancements during the next 10 years of operation, and then more widespread changes before the transition to the highest luminosities after 2022. This talk will describe several components of the ATLAS upgrade, focusing in particular on the Inner Detector and Trigger. The Inner Detector faces two challenges in the higher luminosity environment: high particle multiplicities and increased radiation dose. These will be addressed in the short term by a new layer of Pixel detectors, and in the long term by a complete replacement. The Trigger faces an increasingly difficult task of distinguishing...

  17. Upgradation of Apsara reactor

    International Nuclear Information System (INIS)

    Mammen, S.; Mukherjee, P.; Bhatnagar, A.; Sasidharan, K.; Raina, V.K.

    2009-01-01

    Apsara is a 1 MW swimming pool type research reactor using high enriched uranium as fuel with light water as coolant and moderator. The reactor is in operation for more than five decades and has been extensively used for basic research, radioisotope production, neutron radiography, detector testing, shielding experiments etc. In view of its long service period, it is planned to carry out refurbishment of the reactor to extend its useful life. During refurbishment, it is also planned to upgrade the reactor to a 2 MW reactor to improve its utilization and to upgrade the structure, system and components in line with the current safety standards. This paper gives a brief account of the design features and safety aspects of the upgraded Apsara reactor. (author)

  18. Comprehensive z-dependent measurements of electron-beam microbunching using COTR in a saturated SASE FEL

    CERN Document Server

    Lumpkin, Alex H; Lewellen, J W; Berg, W; Biedron, S G; Borland, M; Chae, Y; Erdmann, M; Huang, Z; Kim, K J; Li, Y; Milton, S V; Moog, E; Rule, D W; Sajaev, Vadim; Yang, B X

    2002-01-01

    We report the initial, comprehensive set of z-dependent measurements of electron-beam microbunching using coherent optical transition radiation (Cot) in a saturated self-amplified spontaneous emission (SASE) free-electron laser (FEL) experiment. In this case the FEL was operated near 530 nm using an enhanced facility including a bunch-compressed photocathode gun electron beam, linac, and 21.6 m of undulator length. The longitudinal microbunching was tracked by inserting a metal foil and mirror after each of the nine 2.4-m-long undulators and measuring the visible COTR spectra, intensity, angular, distribution, and spot size. We observed for the first time the z-dependent transition of the COTR spectra from simple lines to complex structure/sidebands near saturation. We also observed the change in the microbunching fraction after saturation, multiple fringes in the COTR interferogram that are consistent with involvement of a smaller core of the e-beam transverse distribution, and the second harmonic content of...

  19. Design considerations and analysis of potential applications of a high power ultraviolet FEL at the TESLA test facility at DESY

    International Nuclear Information System (INIS)

    Pagani, C.; Saldin, E.L.; Schneidmiller, E.A.; Yurkov, M.V.

    1999-01-01

    A possibility of constructing a high power ultraviolet free electron laser at the TESLA test facility at DESY is discussed. The proposed facility consists of a tunable master oscillator (P av ∼10 mW, P peak ∼10 kW, λ≅200-350 nm) and an FEL amplifier with a tapered undulator. The average and peak radiation power at the exit of the FEL amplifier is about 7 kW and 220 GW, respectively. Installation of such a facility can significantly extend scientific potential of the TESLA test facility. The UV free electron laser can be used to construct a polarized, monochromatic gamma-source with the ultimate yield up to 10 12 gamma-quanta per second and the maximal energy of about 100 MeV. An intensive gamma-source can also form the base for constructing the test facility for the TESLA positron generation system. Another accelerator application of the proposed facility is verification of the main technical solutions for the laser and the optical system to be used in the gamma-gamma option of the TESLA collider. A high average power UV laser is also promising for industrial applications

  20. The UKIRT Upgrades Programme

    Science.gov (United States)

    Adamson, Andy; Davies, John; Robson, Ian

    Tim Hawarden presented this paper to the 30th anniversary workshop, just a month before his untimely death. The editors have done their best to convert his talk into this paper, and gratefully acknowledge the assistance of Nick Rees (a member of the Upgrades team, now at Diamond Light Source). Tim's discussion concerned the UKIRT Upgrades Project, which ran through the 1990s and transformed the telescope and made it truly competitive on the world stage for operation into the twenty-first century. The reference list at the end of the paper is comprehensive; some of these are referred to in the paper itself and some are included for completeness only.

  1. AGS intensity upgrades

    International Nuclear Information System (INIS)

    Roser, T.

    1995-01-01

    After the successful completion of the AGS Booster and several upgrades of the AGS, a new intensity record of 6.3 x 10 13 protons per pulse accelerated to 24 GeV was achieved. The high intensity slow-extracted beam program at the AGS typically serves about five production targets and about eight experiments including three rare Kaon decay experiments. Further intensity upgrades are being discussed that could increase the average delivered beam intensity by up to a factor of four

  2. OMEGA upgrade staging options

    International Nuclear Information System (INIS)

    Kelly, J.H.; Shoup, M.J.; Smith, D.L.

    1989-01-01

    The authors discuss how they are designing an upgrade to its 24-beam OMEGA laser system, OMEGA is a frequency tripled, all-rod system capable of producing 2 kJ at 0.8 ns on target. Important direct-drive-target-ignition physics could be investigated with an upgraded system capable of producing a shaped pulse consisting of a long (5ns) low-intensity, foot, smoothly transitioning into a short (0.5 ns), intense, compression pulse. The total pulse energy is 30 kJ, which, from target-irradiation uniformity considerations, must be distributed over 60 beams

  3. Start-effect measurement of high FEL [free-electron laser] electric fields in MTX [Microwave Tokamak Experiment] by laser-aided particle-probe spectroscopy

    International Nuclear Information System (INIS)

    Oda, T.; Takiyama, K.; Odajima, K.; Ohasa, K.; Shiho, M.; Mizuno, K.; Foote, J.H.; Nilson, D.G.

    1990-01-01

    We are constructing a diagnostic system to measure the electric field (>100 kV/cm) of a free-electron laser (FEL) beam when injected into the plasma of the Microwave Tokamak Experiment (MTX). The apparatus allows a crossed-beam measurement, with 2-cm spatial resolution in the plasma, involving the FEL beam (with 140-GHz, ∼1-GW ECH pulses), a neutral-helium beam, and a dye-laser beam. After the laser beam pumps metastable helium atoms to higher excited states, their decay light is detected by an efficient optical system. Because of the Stark effect arising from the FEL electric field (rvec E), a forbidden transition can be strongly induced. The intensity of emitted light resulting from the forbidden transition is proportional to E 2 . Because photon counting rates are estimated to be low, extra effort is made to minimize background and noise levels. It is possible that the lower rvec E of an MTX gyrotron-produced ECH beam with its longer-duration pulses can also be measured using this method. Other applications of the apparatus described here may include measurements of ion temperature (using charge-exchange recombination), edge-density fluctuations, and core impurity concentrations

  4. Characteristics of the FEL project for the MUH experiment; Stato del progetto FEL per l`esperimeto MUH

    Energy Technology Data Exchange (ETDEWEB)

    Ciocci, F.; Doria, A.; Fascetti, M.; Gallerano, G.P.; Giannessi, L.; Giovenale, E.; Messina, G.; Picardi, L.; Renieri, A.; Ronci, G.; Ronsivalle, C.; Vignati, A. [ENEA, Centro Ricerche Frascati, Rome (Italy). Dip. Innovazione

    1999-01-01

    The design characteristics of a compact Free Electron Laser (FEL) operating in the far infrared spectral range between 200 and 600 {mu}m are presented in this report. The device can be employed in a fundamental physics experiment to be performed in collaboration with INFN-Trieste and the Paul Sherrer Institute- Villigen. Spectroscopic measurements in the above spectral region will allow one to determine the energy difference between the levels 3D-3P in the {mu}P system with great accuracy. [Italiano] In questo rapporto vengono presentate le caratteristiche di progetto di un Laser ad Elettroni Liberi (FEL) compatto operante nel lontano infrarosso a lunghezze d`onda comprese tra 200 e 600 {mu}m. Tale laser potra` essere impiegato in un esperimento di fisica fondamentale su idrogeno muonico in collaborazione con INFN-Trieste ed il Paul Sherrer Institute-Villigen. Le misure spettroscopiche nella regione spettrale del lontano infrarosso consentiranno di determinare con grande accuratezza la differenza di energia dei livelli 3D-3P nel sistema {mu}P. Attraverso la misura di questa transizione sara` possibile effettuare un test delle correzioni di Meccanica Quantistica (QED) alle energie di legame, migliorando di un ordine di grandezza l`accuratezza della misura della polarizzazione del vuoto.

  5. Performance of a Combined System Using an X-Ray FEL Oscillator and a High-Gain FEL Amplifier

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, L.; Lindberg, R.; Kim, K. -J.

    2017-06-01

    The LCLS-II at SLAC will feature a 4 GeV CW superconducting (SC) RF linac [1] that can potentially drive a 5th harmonic X-Ray FEL Oscillator (XFELO) to produce fully coherent, 1 MW photon pulses with a 5 meV bandwidth at 14.4 keV [2]. The XFELO output can serve as the input seed signal for a high-gain FEL amplifier employing fs electron beams from the normal conducting SLAC linac, thereby generating coherent, fs x-ray pulses with TW peak powers using a tapered undulator after saturation [3]. Coherent, intense output at several tens of keV will also be feasible if one considers a harmonic generation scheme. Thus, one can potentially reach the 42 keV photon energy required for the MaRIE project [4] by beginning with an XFELO operating at the 3rd harmonic to produce 14.0 keV photons using a 12 GeV SCRF linac, and then subsequently using the high-gain harmonic generation scheme to generate and amplify the 3th harmonic at 42 keV [5]. We report extensive GINGER simulations that determine an optimized parameter set for the combined system.

  6. Upgrade of the CMS hardron calorimeter for an upgraded LHC

    OpenAIRE

    Anderson, Jake

    2012-01-01

    The CMS barrel and endcap hadron calorimeters (Hcal) upgrading the current photo-sensors are hybrid photodiodes (HPDs) to meet the demands of the upgraded luminosity of the LHC. A key aspect of the Hcal upgrade is to add longitudinal segmentation to improve background rejection, energy resolution, and electron isolation at L1 trigger. The increased segmentation can be achieved by replacing the HPD's with multi-pixel Geiger-mode avalanche photodiodes. The upgraded electron...

  7. Capacity upgrade in short-reach optical fibre networks: simultaneous 4-PAM 20 Gbps data and polarization-modulated PPS clock signal using a single VCSEL carrier

    Science.gov (United States)

    Isoe, G. M.; Wassin, S.; Gamatham, R. R. G.; Leitch, A. W. R.; Gibbon, T. B.

    2017-11-01

    In this work, a four-level pulse amplitude modulation (4-PAM) format with a polarization-modulated pulse per second (PPS) clock signal using a single vertical cavity surface emitting laser (VCSEL) carrier is for the first time experimentally demonstrated. We propose uncomplex alternative technique for increasing capacity and flexibility in short-reach optical communication links through multi-signal modulation onto a single VCSEL carrier. A 20 Gbps 4-PAM data signal is directly modulated onto a single mode 10 GHz bandwidth VCSEL carrier at 1310 nm, therefore, doubling the network bit rate. Carrier spectral efficiency is further maximized by exploiting the inherent orthogonal polarization switching of the VCSEL carrier with changing bias in transmission of a PPS clock signal. We, therefore, simultaneously transmit a 20 Gbps 4-PAM data signal and a polarization-based PPS clock signal using a single VCSEL carrier. It is the first time a signal VCSEL carrier is reported to simultaneously transmit a directly modulated 20 Gbps 4-PAM data signal and a polarization-based PPS clock signal. We further demonstrate on the design of a software-defined digital signal processing (DSP)-assisted receiver as an alternative to costly receiver hardware. Experimental results show that a 3.21 km fibre transmission with simultaneous 20 Gbps 4-PAM data signal and polarization-based PPS clock signal introduced a penalty of 3.76 dB. The contribution of polarization-based PPS clock signal to this penalty was found out to be 0.41 dB. Simultaneous distribution of data and timing clock signals over shared network infrastructure significantly increases the aggregated data rate at different optical network units (ONUs), without costly investment.

  8. Proceedings of the 3rd topical meeting on FEL and high power radiation

    International Nuclear Information System (INIS)

    Hiramatsu, Shigenori

    1994-01-01

    The meeting was held on June 10 and 11, 1993, at the National Laboratory for High Energy Physics. This is the joint study meeting with 31st large power microwave-milliwave study meeting. At the meeting, lectures were given on the report of 1st Asia FEL study meeting, infrared free electron laser (FEL) project in JAERI, present state of Free Electron Laser Research Institute Inc., infrared FEL experiment in the Institute of Scientific and Industrial Research, Osaka University, FEL experiment in UVSOR storage ring, NIJI-4 SRFEL, simulation of FEL oscillation in photo-klystron, vacuum UVFEL in PF, beam characteristics of small photon storage ring, micro-cherenkov FEL using field emission array, coherent spontaneous emission and radiation build-up in FEL oscillator, stability of soft X-ray multilayers under exposure to multipole Wigger radiation, long life Zn 2 excimer excited with relativistic electron beam, development of large power klystron in KEK, design of 1 THz gyrotron and first experiment, experiment of relativistic peniotron, experiments of 3rd and 10th cyclotron harmonic peniotron oscillators and others. (K.I.)

  9. OMEGA Upgrade preliminary design

    International Nuclear Information System (INIS)

    Craxton, R.S.

    1989-10-01

    The OMEGA laser system at the Laboratory for Laser Energetics of the University of Rochester is the only major facility in the United States capable of conducting fully diagnosed, direct-drive, spherical implosion experiments. As such, it serves as the national Laser Users Facility, benefiting scientists throughout the country. The University's participation in the National Inertial Confinement Fusion (ICF) program underwent review by a group of experts under the auspices of the National Academy of Sciences (the Happer Committee) in 1985. The Happer Committee recommended that the OMEGA laser be upgraded in energy to 30 kJ. To this end, Congress appropriated $4,000,000 for the preliminary design of the OMEGA Upgrade, spread across FY88 and FY89. This document describes the preliminary design of the OMEGA Upgrade. The proposed enhancements to the existing OMEGA facility will result in a 30-kHJ, 351-nm, 60-beam direct-drive system, with a versatile pulse-shaping facility and a 1%--2% uniformity of target drive. The Upgrade will allow scientists to explore the ignition-scaling regime, and to study target behavior that is hydrodynamically equivalent to that of targets appropriate for a laboratory microfusion facility (LMF). In addition, it will be possible to perform critical interaction experiments with large-scale-length uniformly irradiated plasmas

  10. Treat upgrade fuel fabrication

    International Nuclear Information System (INIS)

    Davidson, K.V.; Schell, D.H.

    1979-01-01

    An extrusion and thermal treatment process was developed to produce graphite fuel rods containing a dispersion of enriched UO 2 . These rods will be used in an upgraded version of the Transient Reactor Test Facility (TREAT). The improved fuel provides a higher graphite matrix density, better fuel dispersion and higher thermal capabilities than the existing fuel

  11. ATLAS Pixel Detector Upgrade

    CERN Document Server

    Flick, T; The ATLAS collaboration

    2009-01-01

    The first upgrade for higher luminosity at LHC for the ATLAS pixel detector is the insertion of a forth layer, the IBL. The talk gives an overview about what the IBL is and how it will be set up, as well as to give a status of the research and develoment work.

  12. Upgrading Undergraduate Biology Education

    Science.gov (United States)

    Musante, Susan

    2011-01-01

    On many campuses throughout the country, undergraduate biology education is in serious need of an upgrade. During the past few decades, the body of biological knowledge has grown exponentially, and as a research endeavor, the practice of biology has evolved. Education research has also made great strides, revealing many new insights into how…

  13. Upgrade of telephone exchange

    CERN Multimedia

    2006-01-01

    As part of the upgrade of telephone services, work will be carried out on the CERN switching centre between Monday 23 October 8.00 p.m. and Tuesday 24 October 2.00 a.m. Telephone services may be disrupted and possibly even interrupted during this operation. We apologise in advance for any inconvenience this may cause. CERN TELECOM Service

  14. Optimization of the coupling of optical fibers to an SiPM for a scintillator upgrade of the Pierre Auger Observatory

    Energy Technology Data Exchange (ETDEWEB)

    Kemp, Julian; Bretz, Thomas; Hebbeker, Thomas; Meissner, Rebecca; Middendorf, Lukas; Niggemann, Tim; Peters, Christine; Schumacher, Johannes [III. Physikalisches Institut A, RWTH Aachen University (Germany); Collaboration: Pierre-Auger-Collaboration

    2016-07-01

    The Pierre Auger Observatory successfully measures cosmic-ray air-showers at the highest energies by detecting both the fluorescence light produced in the atmosphere and the particle density of the shower at the ground. Nevertheless, this procedure does not allow for a precise measurement of the muon to electron ratio of a single shower. As this quantity is connected to the mass of the primary particle, it allows for a cosmic-ray mass composition measurement. To improve the ability of separating muons from the electromagnetic component, scintillator based detectors will be added to each surface detector station. The basic design will consist of several scintillator bars feeding the produced light into a bundle of wavelength shifting fibers. The light can be detected by photomultipliers (PMTs) or by silicon photomultipliers (SiPMs). The latter benefit from their higher photon detection efficiency and robustness. Due to the smaller area of the SiPMs compared to a PMT, the light detection efficiency of this system strongly depends on the quality of the optical coupling of the fiber bundle to the SiPM. Possible solutions are compared.

  15. SRS control system upgrade requirements

    International Nuclear Information System (INIS)

    Hill, L.F.

    1998-01-01

    This document defines requirements for an upgrade of the Sodium Removal System (SRS) control system. The upgrade is being performed to solve a number of maintainability and operability issues. The upgraded system will provide the same functions, controls and interlocks as the present system, and in addition provide enhanced functionality in areas discussed in this document

  16. Jefferson Lab IR demo FEL photocathode quantum efficiency scanner

    CERN Document Server

    Gubeli, J; Grippo, A; Jordan, K; Shinn, M; Siggins, T

    2001-01-01

    Jefferson Laboratory's Free Electron Laser (FEL) incorporates a cesiated gallium arsenide (GaAs) DC photocathode gun as its electron source. By using a set of scanning mirrors, the surface of the GaAs wafer is illuminated with a 543.5nm helium-neon laser. Measuring the current flow across the biased photocathode generates a quantum efficiency (QE) map of the 1-in. diameter wafer surface. The resulting QE map provides a very detailed picture of the efficiency of the wafer surface. By generating a QE map in a matter of minutes, the photocathode scanner has proven to be an exceptional tool in quickly determining sensitivity and availability of the photocathode for operation.

  17. Development of web database system for JAERI ERL-FEL

    International Nuclear Information System (INIS)

    Kikuzawa, Nobuhiro

    2005-01-01

    The accelerator control system for the JAERI ERL-FEL is a PC-based distributed control system. The accelerator status record is stored automatically through the control system to analyze the influence on the electron beam. In order to handle effectively a large number of stored data, it is necessary that the required data can be searched and visualized in easy operation. For this reason, a web database (DB) system which can search of the required data and display visually on a web browser was developed by using open source software. With introduction of this system, accelerator operators can monitor real-time information anytime, anywhere through a web browser. Development of the web DB system is described in this paper. (author)

  18. Development of web database system for JAERI ERL-FEL

    Energy Technology Data Exchange (ETDEWEB)

    Kikuzawa, Nobuhiro [Japan Atomic Energy Research Inst., Kansai Research Establishment, Advanced Photon Research Center, Tokai, Ibaraki (Japan)

    2005-06-01

    The accelerator control system for the JAERI ERL-FEL is a PC-based distributed control system. The accelerator status record is stored automatically through the control system to analyze the influence on the electron beam. In order to handle effectively a large number of stored data, it is necessary that the required data can be searched and visualized in easy operation. For this reason, a web database (DB) system which can search of the required data and display visually on a web browser was developed by using open source software. With introduction of this system, accelerator operators can monitor real-time information anytime, anywhere through a web browser. Development of the web DB system is described in this paper. (author)

  19. Undulators to FELs: Nanometers, Femtoseconds, Coherence and Applications

    Energy Technology Data Exchange (ETDEWEB)

    Attwood, David [University of California Berkeley

    2011-11-30

    For scientists in many fields, from material science to the life sciences and archeology, synchrotron radiation, and in particular undulator radiation, has provide an intense source of x-rays which are tunable to the absorption edges of particular elements of interest, often permitting studies at high spatial and spectral resolution. Now a close cousin to the undulator, the x-ray free electron laser (XFEL) has emerged with improved spatial coherence and, perhaps more importantly, femtosecond pulse durations which permit dynamical studies. In the future attosecond x-ray capabilities are anticipated. In this colloqium we will describe some state of the art undulator studies, how undulators work, the evolution to FELs, their pulse and coherence properties, and the types of experiments envisioned.

  20. Study of CSR Effects in the Jefferson Laboratory FEL Driver

    Energy Technology Data Exchange (ETDEWEB)

    Hall, C. C. [Colorado State U.; Biedron, S. [Colorado State U.; Burleson, Theodore A. [Colorado State U.; Milton, Stephen V. [Colorado State U.; Morin, Auralee L. [Colorado State U.; Benson, Stephen V. [JLAB; Douglas, David R. [JLAB; Evtushenko, Pavel E. [JLAB; Hannon, Fay E. [JLAB; Li, Rui [JLAB; Tennant, Christopher D. [JLAB; Zhang, Shukui [JLAB; Carlsten, Bruce E. [LANL; Lewellen, John W. [LANL

    2013-08-01

    In a recent experiment conducted on the Jefferson Laboratory IR FEL driver the effects of Coherent Synchrotron Radiation (CSR) on beam quality were studied. The primary goal of this work was to explore CSR output and effect on the beam with variation of the bunch compression in the IR chicane. This experiment also provides a valuable opportunity to benchmark existing CSR models in a system that may not be fully represented by a 1-D CSR model. Here we present results from this experiment and compare to initial simulations of CSR in the magnetic compression chicane of the machine. Finally, we touch upon the possibility for CSR induced microbunching gain in the magnetic compression chicane, and show that parameters in the machine are such that it should be thoroughly damped.

  1. High-harmonic relativistic gyrotron as an alternative to FEL

    Energy Technology Data Exchange (ETDEWEB)

    Bratman, V L; Kalynov, Yu K; Kolganov, N G; Manuilov, V N; Ofitserov, M M; Samsonov, S V; Volkov, A B [Russian Academy of Sciences, Nizhny Novgorod (Russian Federation). Inst. of Applid Physics

    1997-12-31

    A submillimeter wave gyrotron operating at moderately relativistic electron energies of 200-300 keV is proposed as a simple alternative to FEL. It is shown that high pulsed magnetic fields of 20-30 T and selective excitation of separate modes for resonances up to the 5-7 th harmonics will make it possible to obtain in a single device the coherent radiation with broadband frequency step tuning within the whole submillimeter wavelength range. At large pitch angles the coupling of the electron beam with cavity modes at higher harmonics should be as strong as at the fundamental one. In order to check the theoretical predictions, two gyrotrons were designed: LOG-1 (250 kV, 10 A, 10 ms) with a thermionic emission cathode and LOG-2 (350 kV, 35 A, 20 ns) with an explosive emission cathode. (J.U.). 7 refs.

  2. Lasing attempts with a microwiggler on the Los Alamos FEL

    International Nuclear Information System (INIS)

    Warren, R.W.; O'Shea, P.G.; Bender, S.C.; Carlsten, B.E.; Early, J.W.; Feldman, D.W.; Fortgang, C.M.; Goldstein, J.C.; Schmitt, M.J.; Stein, W.E.; Wilke, M.D.; Zaugg, T.J.; Newnam, B.E.; Sheffield, R.L.

    1992-01-01

    The APEX FEL normally lases near a wavelength of 3μm using a permanent magnet wiggler with a 2.7-cm period and a linear accelerator of 40-MeV energy. Los Alamos National Laboratory is conducting a series of experiments with the goal of lasing at significantly shorter wavelengths with the same accelerator and the same kind of near-concentric resonator, but using a novel pulsed microwiggler of 0.5-cm period capable of generating a peak field of several tesla. We plan to lase on a fundamental wavelength of ∼0.8 μm and on the third harmonic at 0.25 μm

  3. Los Alamos free-electron laser (FEL) rf system

    International Nuclear Information System (INIS)

    Tallerico, P.J.; Lynch, M.T.

    1985-01-01

    The FEL rf system was designed for 3.6-MW rf pulses from two klystrons to drive two linacs and one deflection cavity at 1300 MHz. Two 108.33-MHz subharmonic buncher cavities and one fundamental buncher were also built, each powered by a 5-kW amplifier. A single phase-coherent source drives the various amplifiers as well as the grid of the electron gun, which is pulsed at 21.67 MHz. The initial buncher system did not work as well as expected, and the first linac tank required more rf power than anticipated. The light output was extremely sensitive to amplitude and phase errors. More powerful klystrons were developed and installed, and a method was discovered for operating a single subharmonic buncher and allowing the first linac to complete the bunching process. This paper shows the actual configuration used to operate the laser and discusses future improvements

  4. Performing instrumentation and controls upgrades

    International Nuclear Information System (INIS)

    Kessler, F. M.; Connell, T. J.; Ryan, M. P.

    1992-01-01

    I and C upgrades are comprised of a varying range of content, complexity, expansiveness, and criticality. There are common threads in all upgrades which can be simplified by the development of a long term I and C upgrade plan. The development of a such a plan can establish effective ground rules for upgrades, large and small. It can be the basis from which to begin an upgrade evaluation and the standard which is used to compare the degree of compliance of any upgrade regarding the plan or to define the differences from the plan and an individual upgrade. Primary motivation for I and C upgrades are obsolescence and unavailability of spare parts. Numerous other areas of consideration are also involved in an upgrade. Today's technology results in most upgrades largely or totally utilizing digital equipment. The use of digital equipment is fairly new in many I and C applications and requires an elaborate evaluation from functional, qualification, operational, and licensing perspectives as well as others. A well defined upgrade plan developed as a basis for I and C upgrades is a significant start to ensuring an effective upgrade process. Properly developed and implemented, the plan will support I and C upgrade efforts to ensure that the intricacies associated with such tasks eliminate the existing problems which require the upgrade to be performed. The upgrade plan also results in ensuring the maximum benefit from all perspectives of the plant enhancements being carried out and considered for future implementation. Instrumentation and controls aging and replacement are issues of growing importance due to the potential for significant impact on plant operation and efficiency. Obsolescence and unavailability of spare parts are major drivers towards evaluating the cost benefits of upgrading current equipment. In addition to these two primary factors, the advantages of utilizing digital equipment have also become of prime importance when evaluating instrumentation and

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-04-20

    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.

  6. Upgrade of the CMS Global Muon Trigger

    CERN Document Server

    Lingemann, Joschka; Sakulin, Hannes; Jeitler, Manfred; Stahl, Achim

    2015-01-01

    The increase in center-of-mass energy and luminosity for Run 2 of the Large Hadron Collider pose new challenges for the trigger systems of the experiments. To keep triggering with a similar performance as in Run 1, the CMS muon trigger is currently being upgraded. The new algorithms will provide higher resolution, especially for the muon transverse momentum and will make use of isolation criteria that combine calorimeter with muon information already in the level-1 trigger. The demands of the new algorithms can only be met by upgrading the level-1 trigger system to new powerful FPGAs with high bandwidth I/O. The processing boards will be based on the new microTCA standard. We report on the planned algorithms for the upgraded Global Muon Trigger (GMT) which combines information from the muon trigger sub-systems and assigns the isolation variable. The upgraded GMT will be implemented using a Master Processor 7 card, built by Imperial College, that features a large Xilinx Virtex 7 FPGA. Up to 72 optical links at...

  7. Upgrading the ATLAS Tile Calorimeter electronics

    CERN Document Server

    Oreglia, M; The ATLAS collaboration

    2013-01-01

    The Tile Calorimeter (TileCal) is the hadronic calorimeter covering the most central region of the ATLAS experiment at LHC. The TileCal readout consists of about 10000 channels. The main upgrade will occur for the High Luminosity LHC phase (phase 2) which is scheduled around 2022. The upgrade aims at replacing the majority of the on- and off- detector electronics so that all calorimeter signals are directly digitized and sent to the off-detector electronics in the counting room. An ambitious upgrade development program is pursued studying different electronics options. Three different options are presently being investigated for the front-end electronic upgrade. Which one to use will be decided after extensive test beam studies. High speed optical links are used to read out all digitized data to the counting room. For the off-detector electronics a new back-end architecture is being developed, including the initial trigger processing and pipeline memories. A demonstrator prototype read-out for a slice of the ...

  8. Magnetic shielding for FEL microwave electric field diagnostic in MTX tokamak

    International Nuclear Information System (INIS)

    Yamada, Shinichi; Odajima, Kazuo; Ishida, Hiroyasu

    1991-07-01

    A diagnostic system for measurement of microwave electric field from free electron laser (FEL) is in preparation at JAERI under JAERI-DOE collaborative program in the Microwave Tokamak Experiment (MTX) being held at Lawrence Livermore National Laboratory in U.S.A.. That is called LAPPS (Laser Aided Particle Probe Spectroscopy). This is consist of helium neutral beam source, a dye laser and viewing optics. It is required that 1000 gauss of the magnetic field must be shielded to less than 1 gauss in order to operate these LAPPS components. New high performance soft ferrous magnetic material 'FERROPERM' and PERMALLOY are used on this purpose. This paper proposes a new method to estimate a required thickness of the magnetic shielding in a saturated region of B-H curve, that is, 'magnetic shielding calculation by Virtual Divided Layers Method (VDLM)', where the shielding layer is virtually divided in many layers in the calculation. The results are compared with a computer simulation using 'three dimensional static magnetic field code' and with experimental results in a uniform static field. (author)

  9. The effects of magnetic fringe fields on beam dynamics in a beam transport line of a terahertz FEL source

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Han [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan 430074, Hubei (China); Xiong, Yongqian, E-mail: yqxiong@mail.hust.edu.cn [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan 430074, Hubei (China); Pei, Yuanji [National Synchrotron Radiation laboratory, University of Science and Technology of China, Hefei 230029, Anhui (China)

    2014-11-11

    The transport line used in a terahertz FEL device has to transport electron beam through the entire system efficiently and meet the requirements of the beam parameters at the undulator entrance. Due to space limitations, the size of the magnets (five quadrupoles and two bending magnets) employed in the transport line was limited, and some devices were densely packed. In this paper, analyses of the effect of fringe fields and magnetic interference of magnets are presented. 3D models of these magnets are built and their linear optical properties are compared with those obtained by hard edge models. The results indicated that the effects of these factors are significant and they would cause a mismatch of the beam at the exit of the transport line under the preliminary lattice design. To solve this problem, the beam was re-matched using the particle swarm optimization algorithm.

  10. Quasi-real-time photon pulse duration measurement by analysis of FEL radiation spectra

    Energy Technology Data Exchange (ETDEWEB)

    Engel, Robin, E-mail: robin.engel@uni-oldenburg.de [Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22603 Hamburg (Germany); Institut für Physik, Carl von Ossietzky Universität Oldenburg, D-26111 Oldenburg (Germany); Institut für Laser und Optik, Hochschule Emden/Leer, University of Applied Sciences, Constantiaplatz 4, D-26723 Emden (Germany); Düsterer, Stefan; Brenner, Günter [Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22603 Hamburg (Germany); Teubner, Ulrich [Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22603 Hamburg (Germany); Institut für Physik, Carl von Ossietzky Universität Oldenburg, D-26111 Oldenburg (Germany); Institut für Laser und Optik, Hochschule Emden/Leer, University of Applied Sciences, Constantiaplatz 4, D-26723 Emden (Germany)

    2016-01-01

    Considering the second-order spectral correlation function of SASE-FEL radiation allows a real-time observation of the photon pulse duration during spectra acquisition. For photon diagnostics at free-electron lasers (FELs), the determination of the photon pulse duration is an important challenge and a complex task. This is especially true for SASE FELs with strongly fluctuating pulse parameters. However, most techniques require an extensive experimental setup, data acquisition and evaluation time, limiting the usability in all-day operation. In contrast, the presented work uses an existing approach based on the analysis of statistical properties of measured SASE FEL spectra and implements it as a software tool, integrated in FLASH’s data acquisition system. This allows the calculation of the average pulse durations from a set of measured spectral distributions with only seconds of delay, whenever high-resolution spectra are recorded.

  11. Start-to-end simulations of SASE FEL at the TESLA Test Facility

    International Nuclear Information System (INIS)

    Dohlus, M.; Floettmann, K.; Limberg, T.; Saldin, E.L; Schneidmiller, E.A.; Kozlov, O.S.; Yurkov, M.V.; Piot, Ph.

    2004-01-01

    VUV SASE FEL at the TESLA Test Facility (Phase 1) was successfully running and reached saturation in the wavelength range 80-120 nm. We present a posteriori start-to-end simulations of this machine. The codes Astra and elegant are used to track particle distribution from the cathode to the undulator entrance. An independent simulation of the beam dynamics in the bunch compressor is performed with the code CSRtrack. SASE FEL process is simulated with the code FAST. The simulation results are in good agreement with the measured properties of SASE FEL radiation. It is shown that the beam dynamics after the bunch compressor is mainly defined by space charge fields. FEL radiation is produced by the head of the electron bunch having a peak current of about 3 kA and a duration of 100 fs

  12. High average power CW FELs [Free Electron Laser] for application to plasma heating: Designs and experiments

    International Nuclear Information System (INIS)

    Booske, J.H.; Granatstein, V.L.; Radack, D.J.; Antonsen, T.M. Jr.; Bidwell, S.; Carmel, Y.; Destler, W.W.; Latham, P.E.; Levush, B.; Mayergoyz, I.D.; Zhang, Z.X.

    1989-01-01

    A short period wiggler (period ∼ 1 cm), sheet beam FEL has been proposed as a low-cost source of high average power (1 MW) millimeter-wave radiation for plasma heating and space-based radar applications. Recent calculation and experiments have confirmed the feasibility of this concept in such critical areas as rf wall heating, intercepted beam (''body'') current, and high voltage (0.5 - 1 MV) sheet beam generation and propagation. Results of preliminary low-gain sheet beam FEL oscillator experiments using a field emission diode and pulse line accelerator have verified that lasing occurs at the predicted FEL frequency. Measured start oscillation currents also appear consistent with theoretical estimates. Finally, we consider the possibilities of using a short-period, superconducting planar wiggler for improved beam confinement, as well as access to the high gain, strong pump Compton regime with its potential for highly efficient FEL operation

  13. Coherence and linewidth studies of a 4-nm high power FEL

    International Nuclear Information System (INIS)

    Fawley, W.M.; Sessler, A.M.; Scharlemann, E.T.

    1993-05-01

    Recently the SSRL/SLAC and its collaborators elsewhere have considered the merits of a 2 to 4-nm high power FEL utilizing the SLAC linac electron beam. The FEL would be a single pass amplifier excited by spontaneous emission rather than an oscillator, in order to eliminate the need for a soft X-ray resonant cavity. We have used GINGER, a multifrequency 2D FEL simulation code, to study the expected linewidth and coherence properties of the FEL, in both the exponential and saturated gain regimes. We present results concerning the effective shot noise input power and mode shape, the expected subpercent output line widths, photon flux, and the field temporal and spatial correlation functions. We also discuss the effects of tapering the wiggler upon the output power and line width

  14. CMS pixel upgrade project

    CERN Document Server

    Kaestli, Hans-Christian

    2010-01-01

    The LHC machine at CERN finished its first year of pp collisions at a center of mass energy of 7~TeV. While the commissioning to exploit its full potential is still ongoing, there are plans to upgrade its components to reach instantaneous luminosities beyond the initial design value after 2016. A corresponding upgrade of the innermost part of the CMS detector, the pixel detector, is needed. A full replacement of the pixel detector is planned in 2016. It will not only address limitations of the present system at higher data rates, but will aggressively lower the amount of material inside the fiducial tracking volume which will lead to better tracking and b-tagging performance. This article gives an overview of the project and illuminates the motivations and expected improvements in the detector performance.

  15. CMS pixel upgrade project

    CERN Document Server

    INSPIRE-00575876

    2011-01-01

    The LHC machine at CERN finished its first year of pp collisions at a center of mass energy of 7 TeV. While the commissioning to exploit its full potential is still ongoing, there are plans to upgrade its components to reach instantaneous luminosities beyond the initial design value after 2016. A corresponding upgrade of the innermost part of the CMS detector, the pixel detector, is needed. A full replacement of the pixel detector is planned in 2016. It will not only address limitations of the present system at higher data rates, but will aggressively lower the amount of material inside the fiducial tracking volume which will lead to better tracking and b-tagging performance. This article gives an overview of the project and illuminates the motivations and expected improvements in the detector performance.

  16. Acute optic nerve sheath fenestration with the free-electron laser

    Science.gov (United States)

    Shen, Jin-Hui; Casagrande, Vivien A.; Joos, Karen M.; Shetlar, Debra J.; Robinson, Richard D.; Head, William S.; Mavity-Hudson, Julia A.; Nunnally, Amy H.

    1999-06-01

    Purpose: To determine if the free electron laser (FEL) energy can be delivered to a small space to perform optic nerve sheath fenestration with minimal acute nerve damage. Methods: A 530 mm hollow waveguide probe was designed. Optic nerve sheath fenestration (1.0 mm diameter) was performed in 8 rabbits using either the FEL (4 eyes, 6.45mm, 10 Hz, 2 mJ) or a knife (4 eyes). Within 2 hours following surgery, the animals were perfused with aldehyde fixative. The integrity of the optic nerve and glial response at the site of fenestration were evaluated on tissue selections with H&E, and antibodies to S100β or GFAP. Results: Surgery using the FEL probe was found to be technically superior to the knife. The glial reaction was limited to a zone adjacent to the fenestration and was similar in both the FEL and knife incisions. Conclusions: The FEL appears capable of efficiently performing an optic nerve sheath fenestration in a small space with minimal acute damage. Both the FEL and knife incisions result in a rapid glial response at the site of fenestration even when optic nerve integrity is not compromised.

  17. Scaling of gain with energy spread and energy in the PEP FEL

    International Nuclear Information System (INIS)

    Fisher, A.S.

    1992-01-01

    The Sag Harbor paper on the PEP FEL discusses the scaling of various FEL parameters with energy spread σ var-epsilon . I will repeat some of this material here and then examine the benefit of increasing the energy spread. How much energy spread can be achieved with damping wigglers is the next topic. Finally, I consider the dependence of gain and saturation length on beam energy and undulator field

  18. Status and Future Plans of JAERI Eergy-Recovery Linac FEL

    CERN Document Server

    Hajima, R; Kikuzawa, N; Minehara, E J; Nagai, R; Nishimori, N; Nishitani, T; Sawamura, M; Yamauchi, T

    2005-01-01

    An energy-recovery linac for a high-power free-electron laser is in operation at Japan Atomic Energy Research Institute (JAERI). In this paper, we report results of research activities and future plans of JAERI ERL-FEL, which are the construction of FEL transport line, the operation of newly-installed RF controller and IOTs, the development of super-lattice photo cathode.

  19. Face expressive lifting (FEL): an original surgical concept combined with bipolar radiofrequency

    OpenAIRE

    Divaris, Marc; Blugerman, Guillermo; Paul, Malcolm D.

    2013-01-01

    Background Aging can lead to changes in facial expressions, transforming the positive youth expression of happiness to negative expressions as sadness, tiredness, and disgust. Local skin distension is another consequence of aging, which can be difficult to treat with rejuvenation procedures. The “face expressive lifting” (FEL) is an original concept in facial rejuvenation surgery. On the one hand, FEL integrates established convergent surgical techniques aiming to correct the age-related nega...

  20. The CDF upgrade

    International Nuclear Information System (INIS)

    Newman-Holmes, C.

    1995-01-01

    The Collider Detector at Fermilab (CDF) has been used to study proton-antiproton collisions at the Fermilab Tevatron since 1985. Over the years, the detector has evolved steadily to increase its physics capability and to keep pace with improvements to the Tevatron. Fermilab is currently building a new Main Injector accelerator which will lead to even larger luminosity values. This paper describes upgrades to CDF that will allow one to exploit the higher luminosity of the Main Injector

  1. LHCb VELO upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Hennessy, Karol

    2017-02-11

    The upgrade of the LHCb experiment, scheduled for LHC Run-III, scheduled to start in 2021, will transform the experiment to a trigger-less system reading out the full detector at 40 MHz event rate. All data reduction algorithms will be executed in a high-level software farm enabling the detector to run at luminosities of 2×10{sup 33} cm{sup −2} s{sup −1}. The Vertex Locator (VELO) is the silicon vertex detector surrounding the interaction region. The current detector will be replaced with a hybrid pixel system equipped with electronics capable of reading out at 40 MHz. The upgraded VELO will provide fast pattern recognition and track reconstruction to the software trigger. The silicon pixel sensors have 55×55 μm{sup 2} pitch, and are read out by the VeloPix ASIC, from the Timepix/Medipix family. The hottest region will have pixel hit rates of 900 Mhits/s yielding a total data rate of more than 3 Tbit/s for the upgraded VELO. The detector modules are located in a separate vacuum, separated from the beam vacuum by a thin custom made foil. The foil will be manufactured through milling and possibly thinned further by chemical etching. The material budget will be minimised by the use of evaporative CO{sub 2} coolant circulating in microchannels within 400 μm thick silicon substrates. The current status of the VELO upgrade is described and latest results from operation of irradiated sensor assemblies are presented.

  2. Optical guiding and beam bending in free-electron lasers

    International Nuclear Information System (INIS)

    Scharlemann, E.T.

    1987-01-01

    The electron beam in a free-electron laser (FEL) can act as an optical fiber, guiding or bending the optical beam. The refractive and gain effects of the bunched electron beam can compensate for diffraction, making possible wigglers that are many Rayleigh ranges (i.e., characteristic diffraction lengths) long. The origin of optical guiding can be understood by examining gain and refractive guiding in a fiber with a complex index of refraction, providing a mathematical description applicable also to the FEL, with some extensions. In the exponential gain regime of the FEL, the electron equations of motion must be included, but a self-consistent description of exponential gain with diffraction fully included becomes possible. The origin of the effective index of refraction of an FEL is illustrated with a simple example of bunched, radiating dipoles. Some of the properties of the index of refraction are described. The limited experimental evidence for optical beam bending is summarized. The evidence does not yet provide conclusive proof of the existence of optical guiding, but supports the idea. Finally, the importance of refractive guiding for the performance of a high-gain tapered-wiggler FEL amplifier is illustrated with numerical simulations

  3. The LHCb VELO upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Dosil Suárez, Álvaro, E-mail: alvaro.dosil@usc.es

    2016-07-11

    The upgrade of the LHCb experiment, planned for 2019, will transform the experiment to a trigger-less system reading out the full detector at 40 MHz event rate. All data reduction algorithms will be executed in a high-level software farm. The upgraded detector will run at luminosities of 2×10{sup 33} cm{sup −2} s{sup −1} and probe physics beyond the Standard Model in the heavy flavour sector with unprecedented precision. The Vertex Locator (VELO) is the silicon vertex detector surrounding the interaction region. The current detector will be replaced with a hybrid pixel system equipped with electronics capable of reading out at 40 MHz. The detector comprises silicon pixel sensors with 55×55 μm{sup 2} pitch, read out by the VeloPix ASIC, based on the TimePix/MediPix family. The hottest region will have pixel hit rates of 900 Mhits/s yielding a total data rate more than 3 Tbit/s for the upgraded VELO. The detector modules are located in a separate vacuum, separated from the beam vacuum by a thin custom made foil. The detector halves are retracted when the beams are injected and closed at stable beams, positioning the first sensitive pixel at 5.1 mm from the beams. The material budget will be minimised by the use of evaporative CO{sub 2} coolant circulating in microchannels within 400 μm thick silicon substrates.

  4. The D0 upgrade

    International Nuclear Information System (INIS)

    Tuts, P.M.

    1992-10-01

    The original D0 detector was proposed in 1983, with a focus on high P T physics using precision measurements of e's, μ's, jets, and missing E T . This detector, as of the summer of 1992, has started data taking at the Fermilab Collider. However, by 1995/6 the luminosity will reach 10 31 cm -2 sec -1 , and the minimum bunch spacing will drop to 396ns from the present 3.5μs (by the Main Injector era, luminosities will approach 10 32 cm -2 sec -1 and minimum bunch spacings may reach 132ns). These changes in the accelerator conditions force us to upgrade or replace a number of detector subsystems in order to meet these new demands. In addition, the upgrade offers us the opportunity to expand the physics horizons to include not only the all important high P T physics menu, but also the low P T physics that has become increasingly important. In this paper we describe the D0 detector upgrade

  5. ATLAS Upgrade Plans

    CERN Document Server

    Hopkins, W; The ATLAS collaboration

    2014-01-01

    After the successful LHC operation at the center-of-mass energies of 7 and 8 TeV in 2010-2012, plans are actively advancing for a series of upgrades of the accelerator, culminating roughly ten years from now in the high-luminosity LHC (HL-LHC) project, delivering of the order of five times the LHC nominal instantaneous luminosity along with luminosity leveling. The final goal is to extend the dataset from about few hundred fb−1 expected for LHC running to 3000/fb by around 2035 for ATLAS and CMS. In parallel, the experiments need to be keep lockstep with the accelerator to accommodate running beyond the nominal luminosity this decade. Current planning in ATLAS envisions significant upgrades to the detector during the consolidation of the LHC to reach full LHC energy and further upgrades. The challenge of coping with the HL-LHC instantaneous and integrated luminosity, along with the associated radiation levels, requires further major changes to the ATLAS detector. The designs are developing rapidly for a new...

  6. The LHCb VELO upgrade

    International Nuclear Information System (INIS)

    Rodríguez Pérez, Pablo

    2013-01-01

    LHCb is a forward spectrometer experiment dedicated to the study of new physics in the decays of beauty and charm hadrons produced in proton collisions at the Large Hadron Collider (LHC) at CERN. The VErtex LOcator (VELO) is the microstrip silicon detector surrounding the interaction point, providing tracking and vertexing measurements. The upgrade of the LHCb experiment, planned for 2018, will increase the luminosity up to 2×10 33 cm −2 s −1 and will perform the readout as a trigger-less system with an event rate of 40 MHz. Extremely non-uniform radiation doses will reach up to 5×10 15 1 MeV n eq /cm 2 in the innermost regions of the VELO sensors, and the output data bandwidth will be increased by a factor of 40. An upgraded detector is under development based in a pixel sensor of the Timepix/Medipix family, with 55×55μm 2 pixels. In addition a microstrip solution with finer pitch, higher granularity and thinner than the current detector is being developed in parallel. The current status of the VELO upgrade program will be described together with recent testbeam results

  7. The LHCb VELO Upgrade

    CERN Document Server

    de Capua, Stefano

    2016-01-01

    The upgrade of the LHCb experiment, scheduled for LHC Run-3, will transform the experiment to a triggerless system reading out the full detector at 40 MHz event rate. All data reduction algorithms will be executed in a high-level software farm, enabling the detector to run at luminosities of 2×1033 cm−2 s −1 . The Vertex Locator (VELO) is the silicon vertex detector surrounding the interaction region. The current strip detector will be replaced with a hybrid pixel system equipped with electronics capable of reading out at 40 MHz. The upgraded VELO will allow for fast pattern recognition and track reconstruction in the software trigger. The silicon pixel sensors have 55×55 µm2 pitch, and are read out by the VeloPix ASIC. The VeloPix builds on the currently available Timepix3, modified to deliver a radiation hard design capable of an order of magnitude increase in output rate. The hottest regions will have pixel hit rates of 900 Mhits/s, yielding a total data rate more than 3 Tbit/s for the upgraded VELO...

  8. LHCb VELO Upgrade

    CERN Document Server

    Hennessy, Karol

    2016-01-01

    The upgrade of the LHCb experiment, scheduled for LHC Run-III, scheduled to start in 2021, will transform the experiment to a trigger-less system reading out the full detector at 40 MHz event rate. All data reduction algorithms will be executed in a high-level software farm enabling the detector to run at luminosities of $2\\times10^{33} \\mathrm{cm}^{-2}\\mathrm{s}^{-1}$. The Vertex Locator (VELO) is the silicon vertex detector surrounding the interaction region. The current detector will be replaced with a hybrid pixel system equipped with electronics capable of reading out at 40 MHz. The upgraded VELO will provide fast pattern recognition and track reconstruction to the software trigger. The silicon pixel sensors have $55\\times55 \\mu m^{2}$ pitch, and are read out by the VeloPix ASIC, from the Timepix/Medipix family. The hottest region will have pixel hit rates of 900 Mhits/s yielding a total data rate of more than 3 Tbit/s for the upgraded VELO. The detector modules are located in a separate vacuum, separate...

  9. Wake monochromator in asymmetric and symmetric Bragg and Laue geometry for self-seeding the European X-ray FEL

    International Nuclear Information System (INIS)

    Geloni, Gianluca; Kocharyan, Vitali; Saldin, Evgeni; Serkez, Svitozar; Tolkiehn, Martin

    2013-01-01

    We discuss the use of self-seeding schemes with wake monochromators to produce TW power, fully coherent pulses for applications at the dedicated bio-imaging beamline at the European X-ray FEL, a concept for an upgrade of the facility beyond the baseline previously proposed by the authors. We exploit the asymmetric and symmetric Bragg and Laue reflections (sigma polarization) in diamond crystal. Optimization of the bio-imaging beamline is performed with extensive start-to-end simulations, which also take into account effects such as the spatio-temporal coupling caused by the wake monochromator. The spatial shift is maximal in the range for small Bragg angles. A geometry with Bragg angles close to π/2 would be a more advantageous option from this viewpoint, albeit with decrease of the spectral tunability. We show that it will be possible to cover the photon energy range from 3 keV to 13 keV by using four different planes of the same crystal with one rotational degree of freedom.

  10. Wake monochromator in asymmetric and symmetric Bragg and Laue geometry for self-seeding the European X-ray FEL

    Energy Technology Data Exchange (ETDEWEB)

    Geloni, Gianluca [European XFEL GmbH, Hamburg (Germany); Kocharyan, Vitali; Saldin, Evgeni; Serkez, Svitozar; Tolkiehn, Martin [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2013-01-15

    We discuss the use of self-seeding schemes with wake monochromators to produce TW power, fully coherent pulses for applications at the dedicated bio-imaging beamline at the European X-ray FEL, a concept for an upgrade of the facility beyond the baseline previously proposed by the authors. We exploit the asymmetric and symmetric Bragg and Laue reflections (sigma polarization) in diamond crystal. Optimization of the bio-imaging beamline is performed with extensive start-to-end simulations, which also take into account effects such as the spatio-temporal coupling caused by the wake monochromator. The spatial shift is maximal in the range for small Bragg angles. A geometry with Bragg angles close to {pi}/2 would be a more advantageous option from this viewpoint, albeit with decrease of the spectral tunability. We show that it will be possible to cover the photon energy range from 3 keV to 13 keV by using four different planes of the same crystal with one rotational degree of freedom.

  11. Research opportunities at the proposed Los Alamos XUV-FEL user facility

    International Nuclear Information System (INIS)

    Conradson, S.D.; Newman, B.E.

    1990-01-01

    This paper reports that within the last several years a number of meetings and conferences have addressed the unique scientific opportunities which would result from the development of an RF-linac FEL user facility accessing the XUV and mid-IR spectral regions. The capabilities of a number of linear and nonlinear spectroscopies would be enhanced by one or more features of the FEL output, e.g., its free tunability in these regions, transform-limited linewidth, high peak power and brightness, time structure, and the possibility of multi-color pump-probe experiments utilizing the coordinated output from more than one FEL oscillator. These advances would in turn benefit a variety of scientific areas. In the realm of basic science, experiments or measurements which ether require an FEL or where increased sensitivity would be advantageous can be found in quantum, atomic, cluster, molecular, and condensed matter physics, magnetic materials, surface science and catalysis, non-linear spectroscopy, and biophysics and -chemistry and physics, advanced fabrication processes, medical applications, and others. These applications form the basis for the specifications of the FEL and for the design of the laboratories for the proposed FEL user facility at Los Alamos

  12. Development of a novel thermionic RF electron gun applied on a compact THz-FEL facility

    Science.gov (United States)

    Hu, T. N.; Pei, Y. J.; Qin, B.; Liu, K. F.; Feng, G. Y.

    2018-04-01

    The current requirements from civil and commercial applications lead to the development of compact free-electron laser (FEL)-based terahertz (THz) radiation sources. A picosecond electron gun plays an important role in an FEL-THz facility and attracts significant attention, as machine performance is very sensitive to initial conditions. A novel thermionic gun with an external cathode (EC) and two independently tunable cavities (ITCs) has been found to be a promising alternative to conventional electron sources due to its remarkable characteristics, and correspondingly an FEL injector can achieve a balance between a compact layout and high brightness benefitting from the velocity bunching properties and RF focusing effects in the EC-ITC gun. Nevertheless, the EC-ITC gun has not been extensively examined as part of the FEL injector in the past years. In this regard, to fill this gap, a development focusing on the experimental setup of an FEL injector based on an EC-ITC gun is described in detail. Before assembly, dynamic beam simulations were performed to investigate the optimal mounting position for the Linac associated with the focusing coils, and a suitable radio-frequency (RF) system was established based on a power coupling design and allocation. The testing bench proved to be fully functional through basic experiments using typical diagnostic approaches for estimating primary parameters. Associated with dynamic beam calculations, a performance evaluation for an EC-ITC gun was established while providing indirect testing results for an FEL injector.

  13. LS1: electrical engineering upgrades and consolidation

    International Nuclear Information System (INIS)

    Duval, F.

    2012-01-01

    3 different types of activities are planned by the Engineering Department Electrical Engineering (EN-EL) Group for the first long shut down (LS1). First, the consolidation of EN-EL's ageing infrastructure elements. It is part of a 15- year programme aiming at increasing the reliability and availability of the power distribution network. Secondly, the maintenance of the accelerators infrastructure. In addition to the usual periodic operations and those delayed until LS1, the group will address more demanding activities like the replacement campaigns for irradiated cables and non-radiation resistant fibres as well as the removal of unused cables in particularly overcrowded areas. Thirdly, a vast amount of user copper and optical fibre cabling requests: EN-EL estimates that only 50% of LS1 requests are currently known. The main activities will be EN-EL's contributions to the R2E project, BE-BI upgrade projects, and the RF upgrade project in SPS BA3

  14. Upgrading the Atlas Tile Calorimeter Electronics

    CERN Document Server

    Popeneciu, G; The ATLAS collaboration

    2014-01-01

    Tile Calorimeter is the central hadronic calorimeter of the ATLAS experiment at LHC. Around 2024, after the upgrade of the LHC the peak luminosity will increase by a factor of 5 compared to the design value, thus requiring an upgrade of the Tile Calorimeter readout electronics. Except the photomultipliers tubes (PMTs), most of the on- and off-detector electronics will be replaced, with the aim of digitizing all PMT pulses at the front-end level and sending them with 10 Gb/s optical links to the back-end electronics. One demonstrator prototype module is planned to be inserted in Tile Calorimeter in 2015 that will include hybrid electronic components able to probe the new design.

  15. Optics

    CERN Document Server

    Mathieu, Jean Paul

    1975-01-01

    Optics, Parts 1 and 2 covers electromagnetic optics and quantum optics. The first part of the book examines the various of the important properties common to all electromagnetic radiation. This part also studies electromagnetic waves; electromagnetic optics of transparent isotropic and anisotropic media; diffraction; and two-wave and multi-wave interference. The polarization states of light, the velocity of light, and the special theory of relativity are also examined in this part. The second part is devoted to quantum optics, specifically discussing the classical molecular theory of optical p

  16. A study of a transverse optical klystron experiment in adone (TOKA)

    International Nuclear Information System (INIS)

    Boscolo, I.; Stagno, V.; Bari Univ.

    1982-01-01

    The storage ring operation of a free electron laser (FEL) can be improved by a prebunching of the electron beam. We study in this paper a layout working as a transverse optical klystron (TOK). The enhancement of the single pass gain and the consequent reduction of the wiggler length in the TOK compared with the FEL suggests that the first device is more suitable for a storage ring such as Adone, where the straight sections are about 2 m long. The figures of the TOKA are carried out using as much as possible the hardware of the FEL experiment which is in progress at Adone (LELA experiment). (orig.)

  17. Upgrading of TREAT experimental capabilities

    International Nuclear Information System (INIS)

    Dickerman, C.E.; Rose, D.; Bhattacharyya, S.K.

    1982-01-01

    The TREAT facility at the Argonne National Laboratory site in the Idaho National Engineering Laboratory is being upgraded to provide capabilities for fast-reactor-safety transient experiments not possible at any other experimental facility. Principal TREAT Upgrade (TU) goal is provision for 37-pin size experiments on energetics of core-disruptive accidents (CDA) in fast breeder reactor cores with moderate sodium void coefficients. this goal requires a significant enhancement of the capabilities of the TREAT facility, specifically including reactor control, hardened neutron spectrum incident on the test sample, and enlarged building. The upgraded facility will retain the capability for small-size experiments of the types currently being performed in TREAT. Reactor building and crane upgrading have been completed. TU schedules call for the components of the upgraded reactor system to be finished in 1984, including upgraded TREAT fuel and control system, and expanded coverage by the hodoscope fuel-motion diagnostics system

  18. The upgraded LTP-V at SLS

    Energy Technology Data Exchange (ETDEWEB)

    Flechsig, U., E-mail: uwe.flechsig@psi.ch [Paul Scherrer Institut, Swiss Light Source, 5232 Villigen-PSI (Switzerland); Jaggi, A.; Krempaský, J.; Spielmann, S.; Thominet, V. [Paul Scherrer Institut, Swiss Light Source, 5232 Villigen-PSI (Switzerland)

    2013-05-11

    Since 2005 the Swiss Light Source (SLS) has been operating a Long Trace Profiler (LTP)-V from Ocean Optics in its metrology laboratory to measure the synchrotron optics for SLS. In 2012 we finished a significant upgrade to improve the accuracy, reliability and measurement efficiency in particular for the calibration of adaptive optics. Folding mirrors with figure errors <λ/100 and an additional linear encoder have been installed, the 1d CCD detector with 2048 pixels has been replaced by a 16 mega-pixel CCD camera with gigabit ethernet interface GigE, the monolithic software has been replaced by a modular, full- EPICS compatible system based on a new LTP plugin for the areaDetector software for image processing. The plugin allows slope determination in real time i.e. per frame.

  19. The Bevalac Upgrade Project

    International Nuclear Information System (INIS)

    Alonso, J.R.; Dwinell, R.D.; Feinberg, B.

    1987-03-01

    This paper describes a proposed upgrade of the Bevalac accelerator complex in which the present Bevatron is replaced with a modern, strong-focusing 17 T-m synchrotron. This new ring is designed to accelerate all ions throughout the periodic table with intensities 100 to 1000 times higher than the present Bevatron. It will also provide a substantially improved beam spill structure and will reduce operating costs. A fast extraction capability can be used to inject a future heavy ion storage ring. Pulse-to-pulse switching of energy and ion species is an important goal. The existing injectors, shielding, experimental facilities and utilities of the present Bevalac will remain substantially intact

  20. Upgrade Software and Computing

    CERN Document Server

    The LHCb Collaboration, CERN

    2018-01-01

    This document reports the Research and Development activities that are carried out in the software and computing domains in view of the upgrade of the LHCb experiment. The implementation of a full software trigger implies major changes in the core software framework, in the event data model, and in the reconstruction algorithms. The increase of the data volumes for both real and simulated datasets requires a corresponding scaling of the distributed computing infrastructure. An implementation plan in both domains is presented, together with a risk assessment analysis.

  1. Upgrading Enterprise Search

    Energy Technology Data Exchange (ETDEWEB)

    McDunn, R

    2005-04-28

    This presentation will describe the process we went through this past year to upgrade our enterprise search tool from a very old version of Inktomi to the latest version of Verity Ultraseek. We started with requirements gathering and then compared requirements against several available products to determine which product to choose. After purchasing the product, we worked through several defined phases of implementation and customization, with initial rollout late January 2004. Finally, we will show you where we are today and describe future search plans.

  2. Upgrade, rebuild or replace?

    International Nuclear Information System (INIS)

    Forbes, C.A.

    1990-01-01

    Ageing reactor simulators present some tough decisions for utility managers. Although most utilities have chosen the cheaper, upgrading solution as the best compromise between costs and outage length, some US utilities have found that for them, replacement represents the best option. Simulators may be less than ten years old, but they have limited instructor systems, older low fidelity models that cannot reproduce important training scenarios, and out of date, difficult to maintain computers that do not permit much expansion of the models anyway. Perhaps worse than this is the possibility that the simulator may no longer be a faithful reproduction of the referenced plant, or have poor (or non-existent) documentation. (author)

  3. The drive laser for the APS LEUTL FEL Rf photoinjector

    International Nuclear Information System (INIS)

    Arnold, N.; Koldenhoven, R.; Travish, G.

    1999-01-01

    The APS LEUTL free-electron laser (FEL) is a high-gain, short-wavelength device requiring a high-current, low-emittance beam. An rf photoinjector driven by a laser is used to provide the requisite beam. The drive laser consists of a diode-pumped Nd:Glass oscillator and a chirped pulse amplification (CPA) system consisting of a grating stretcher, a flashlamp-pumped Nd:Glass regenerative amplifier, and a grating compressor. The system generates 4-mj pulses in the R with a pulse length as short as 2 ps FWHM and a repetition rate of 6 Hz. Nonlinear doubling crystals are used to generate fourth-harmonic output of ∼500 microJ in the UV (263 nm), which is required to exceed the work function of the copper cathode in the gun. This paper describes the drive laser as well as the extensive controls implemented to allow for remote operation and monitoring. Performance measurements as well as the operating experience are presented

  4. Design and test of SX-FEL cavity BPM

    International Nuclear Information System (INIS)

    Yuan Renxian; Zhou Weimin; Chen Zhichu; Yu Luyang; Wang Baopen; Leng Yongbin

    2013-01-01

    This paper reports the design and cold test of the cavity beam position monitor (CBPM) for SX-FEL to fulfill the requirement of beam position measurement resolution of less than 1 μm, even 0.1 μm. The CBPM was optimized by using a coupling slot to damp the TM 010 mode in the output signal. The isolation of TM 010 mode is about 117 dB, and the shunt impedance is about 200 Ω@4.65 GHz with the quality factor 80 from MAFIA simulation and test result. A special antenna was designed to load power for reducing excitation of other modes in the cavity. The resulting output power of TM 110 mode was about 90 mV/mm when the source was 6 dBm, and the accomplishable minimum voltage was about 200 μV. The resolution of the CBPM was about 0.1 μm from the linear fitting result based on the cold test. (authors)

  5. Management system of ELHEP cluster machine for FEL photonics design

    Science.gov (United States)

    Zysik, Jacek; Poźniak, Krzysztof; Romaniuk, Ryszard

    2006-10-01

    A multipurpose, distributed MatLab calculations oriented, cluster machine was assembled in PERG/ELHEP laboratory at ISE/WUT. It is predicted mainly for advanced photonics and FPGA/DSP based systems design for Free Electron Laser. It will be used also for student projects for superconducting accelerator and FEL. Here we present one specific side of cluster design. For an intense, distributed daily work with the cluster, it is important to have a good interface and practical access to all machine resources. A complex management system was implemented in PERG laboratory. It helps all registered users to work using all necessary applications, communicate with other logged in people, check all the news and gather all necessary information about what is going on in the system, how it is utilized, etc. The system is also very practical for administrator purposes, it helps to keep controlling who is using the resources and for how long. It provides different privileges for different applications and many more. The system is introduced as a freeware, using open source code and can be modified by system operators or super-users who are interested in nonstandard system configuration.

  6. Quadrupole magnets for IR-FEL at RRCAT

    International Nuclear Information System (INIS)

    Ruwali, Kailash; Singh, Kushraj; Mishra, Anil Kumar; Biswas, Bhaskar

    2013-01-01

    The IR-FEL project at RRCAT needs quadrupole magnets for focusing 15 to 35 MeV electron beam through a dog-leg type beam line. This bend needs tighter relative tolerances on the central quadrupole triplet . The magnetic design, fabrication and magnetic characterization of five quadrupole magnets were carried out. The poles are detachable and wider than the coils. This significantly improves the good field region of the magnet. The magnet cross-section was optimized using 2D POISON code and entry-exit tapers were optimized using 3D code TOSCA.. The aperture radius of the magnet is 30 mm and the total core length is 180 mm. The integrated gradient of magnet is 0.51 T. The magnetic measurements were carried out using Danfysik make rotating coil bench model 690. Integrated gradient and multipoles present in the magnet aperture were measured at various excitation levels. The details of magnetic development and the magnetic measurements are discussed in this paper. (author)

  7. Repairing and Upgrading Your PC

    CERN Document Server

    Thompson, Robert

    2009-01-01

    Repairing and Upgrading Your PC delivers start-to-finish instructions, simple enough for even the most inexperienced PC owner, for troubleshooting, repairing, and upgrading your computer. Written by hardware experts Robert Bruce Thompson and Barbara Fritchman Thompson, this book covers it all: how to troubleshoot a troublesome PC, how to identify which components make sense for an upgrade, and how to tear it all down and put it back together. This book shows how to repair and upgrade all of your PC's essential components.

  8. Optics

    CERN Document Server

    Fincham, W H A

    2013-01-01

    Optics: Ninth Edition Optics: Ninth Edition covers the work necessary for the specialization in such subjects as ophthalmic optics, optical instruments and lens design. The text includes topics such as the propagation and behavior of light; reflection and refraction - their laws and how different media affect them; lenses - thick and thin, cylindrical and subcylindrical; photometry; dispersion and color; interference; and polarization. Also included are topics such as diffraction and holography; the limitation of beams in optical systems and its effects; and lens systems. The book is recommen

  9. Validity and reliability of the Fels physical activity questionnaire for children.

    Science.gov (United States)

    Treuth, Margarita S; Hou, Ningqi; Young, Deborah R; Maynard, L Michele

    2005-03-01

    The aim was to evaluate the reliability and validity of the Fels physical activity questionnaire (PAQ) for children 7-19 yr of age. A cross-sectional study was conducted among 130 girls and 99 boys in elementary (N=70), middle (N=81), and high (N=78) schools in rural Maryland. Weight and height were measured on the initial school visit. All the children then wore an Actiwatch accelerometer for 6 d. The Fels PAQ for children was given on two separate occasions to evaluate reliability and was compared with accelerometry data to evaluate validity. The reliability of the Fels PAQ for the girls, boys, and the elementary, middle, and high school age groups range was r=0.48-0.76. For the elementary school children, the correlation coefficient examining validity between the Fels PAQ total score and Actiwatch (counts per minute) was 0.34 (P=0.004). The correlation coefficients were lower in middle school (r=0.11, P=0.31) and high school (r=0.21, P=0.006) adolescents. The sport index of the Fels PAQ for children had the highest validity in the high school participants (r=0.34, P=0.002). The Fels PAQ for children is moderately reliable for all age groups of children. Validity of the Fels PAQ for children is acceptable for elementary and high school students when the total activity score or the sport index is used. The sport index was similar to the total score for elementary students but was a better measure of physical activity among high school students.

  10. Rational design of hypoallergens applied to the major cat allergen Fel d 1.

    Science.gov (United States)

    Saarne, T; Kaiser, L; Grönlund, H; Rasool, O; Gafvelin, G; van Hage-Hamsten, M

    2005-05-01

    Allergen-specific immunotherapy is the only treatment for allergic disease providing long-lasting symptom relief. Currently, it is mainly based on the use of crude allergen extracts. The treatment may be improved by the use of genetically engineered allergens, hypoallergens, aiming at a more effective and safer therapy. The aim of this study was to provide a rational design of hypoallergen candidates for immunotherapy by using structural information and knowledge of B and T cell epitopes of an allergen. The three-dimensional structure of the major cat allergen Fel d 1 was systematically altered by duplication of selected T cell epitopes and disruption of disulphide bonds. Seven Fel d 1 derivatives were generated and screened for allergenic reactivity in comparison with recombinant Fel d 1 in competition-ELISA. The allergenicity was further evaluated in basophil activation experiments and T cell reactivity was assessed in a lymphoproliferation assay. Three out of seven Fel d 1 derivatives, with two duplicated T cell epitopes and one or two disulphide bonds disrupted, were carefully evaluated. The three derivatives displayed a strong reduction in allergenicity with 400-900 times lower IgE-binding capacity than recombinant Fel d 1. In addition, they induced a lower degree of basophil activation and similar or stronger T cell proliferation than recombinant Fel d 1. By a rational approach, we have constructed three Fel d 1 hypoallergens with reduced IgE-binding capacities and retained T cell reactivities. This strategy may be applied to any well-characterized allergen to improve immunotherapy for allergic patients.

  11. Upgraded G-optk program for electron gun characterization

    International Nuclear Information System (INIS)

    Nagasao, K.; Takebe, M.; Ushio, W.; Fujita, S.; Ohye, T.; Shimoyama, H.

    2011-01-01

    The generalized trajectory theory (the G-optk program) has been extended in order to make the method applicable to electron guns with curved and/or asymmetric cathodes. The object-image analysis mode has also been added. Enhanced capability of the upgraded G-optk program was demonstrated by applying the program to three electron optical systems: (a) the point cathode gun, (b) the hairpin-type cathode gun, and (c) the LEEM objective lens. The Canonical Mapping Transformation (CMT) diagrams were calculated both by direct ray tracing and by the upgraded G-optk program. In each case, it was found that the upgraded program reproduces well the results obtained by ray tracing. The generalized trajectory method has several advantages over direct ray tracing, such as substantially lighter calculation load and easy interpretation of the calculation results in terms of the optical parameters.

  12. The experience of the FERMI@Elettra photon beam transport and diagnostics system (PADReS) during three years of continuous support of machine and user experiments: achievements, lessons learned, and future upgrades

    Science.gov (United States)

    Zangrando, Marco; Fava, Claudio; Gerusina, Simone; Gobessi, Riccardo; Mahne, Nicola; Mazzucco, Eric; Raimondi, Lorenzo; Rumiz, Luca; Svetina, Cristian

    2014-09-01

    The FERMI FEL facility has begun delivering photons in 2011, becoming in late 2012 the first seeded facility open to external users worldwide. Since then, several tens of experiments have been carried out on the three operative endstations LDM, DiProI, and EIS-TIMEX. Starting from the commissioning phase, the transport and diagnostics system (PADReS) has been continuously developed and upgraded, becoming the indispensable interface between the machine and the experimental chambers. Moreover, PADReS itself has served as an active player for several machine studies as well as for various state-of-the-art experiments. In particular, some elements of PADReS have become key features to perform cutting edge experiments: the online energy spectrometer, the active optics refocusing systems, the split and delay line, and so on. For each of them the peculiar advantages will be described showing the actual implementation in the experiments. The experience gathered so far in fulfilling the needs of both machine and experimental physicists will be discussed, with particular emphasis on the solutions adopted in different scenarios. Recurrent requests and major difficulties will be reported so to give a glimpse about the standard tasks to be solved when preparing new and demanding experiments. Finally, some ideas and near-future improvements will be presented and discussed.

  13. ATLAS Detector Upgrade Prospects

    CERN Document Server

    Dobre, Monica; The ATLAS collaboration

    2016-01-01

    After the successful operation at the center-of-mass energies of 7 and 8 TeV in 2010 - 2012, the LHC is ramped up and successfully took data at the center-of-mass energies of 13 TeV in 2015. Meanwhile, plans are actively advancing for a series of upgrades of the accelerator, culminating roughly ten years from now in the high-luminosity LHC (HL-LHC) project, delivering of the order of five times the LHC nominal instantaneous luminosity along with luminosity leveling. The ultimate goal is to extend the dataset from about few hundred fb−1 expected for LHC running to 3000 fb−1 by around 2035 for ATLAS and CMS. The challenge of coping with the HL-LHC instantaneous and integrated luminosity, along with the associated radiation levels, requires further major changes to the ATLAS detector. The designs are developing rapidly for a new all-silicon tracker, significant upgrades of the calorimeter and muon systems, as well as improved triggers and data acquisition. ATLAS is also examining potential benefits of extens...

  14. ATLAS detector upgrade prospects

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00184940; The ATLAS collaboration

    2017-01-01

    After the successful operation at the centre-of-mass energies of 7 and 8 TeV in 2010-2012, the LHC is ramped up and successfully took data at the centre-of-mass energies of 13 TeV in 2015. Meanwhile, plans are actively advancing for a series of upgrades of the accelerator, culminating roughly ten years from now in the high-luminosity LHC (HL-LHC) project, delivering of the order of five times the LHC nominal instantaneous luminosity along with luminosity levelling. The ultimate goal is to extend the dataset from about few hundred fb$^{-1}$ expected for LHC running to 3000 fb $^{-1}$ by around 2035 for ATLAS and CMS. The challenge of coping with the HL-LHC instantaneous and integrated luminosity, along with the associated radiation levels, requires further major changes to the ATLAS detector. The designs are developing rapidly for a new all-silicon tracker, significant upgrades of the calorimeter and muon systems, as well as improved triggers and data acquisition. ATLAS is also examining potential benefits of ...

  15. LHCb VELO Upgrade

    CERN Document Server

    van Beuzekom, Martin; Ketel, Tjeerd; Gershon, Timothy; Parkes, Christopher; Reid, Matthew

    2011-01-01

    The VErtex LOcator (VELO) is a vital piece of apparatus for allowing precision measurements in hadronic physics. It provides not only superb impact parameter resolutions but also excellent momentum resolution, both important discriminating tools for precision high energy physics. This poster focuses on the R&D going into the future LHCb VELO detector. At present there are two proposed options for the upgrade; pixel chips or strip detectors. The LHCb upgrade is designed with higher luminosities and increased yields in mind. In order to get more out of the LHCb detector changes to the front end electronics will have to be made. At present, the first level hardware trigger is sets a limiting factor on the maximum efficiency for hadronic channels. As the VELO is positioned so close the proton-proton interaction region, whatever the choice of sensor, we will require efficient cooling and some proposed solutions are outlined. The LHCb TimePix telescope has had a very successful years running, with various devic...

  16. ATLAS Detector Upgrade Prospects

    International Nuclear Information System (INIS)

    Dobre, M

    2017-01-01

    After the successful operation at the centre-of-mass energies of 7 and 8 TeV in 2010-2012, the LHC was ramped up and successfully took data at the centre-of-mass energies of 13 TeV in 2015 and 2016. Meanwhile, plans are actively advancing for a series of upgrades of the accelerator, culminating roughly ten years from now in the high-luminosity LHC (HL-LHC) project, which will deliver of the order of five times the LHC nominal instantaneous luminosity along with luminosity levelling. The ultimate goal is to extend the dataset from about few hundred fb −1 expected for LHC running by the end of 2018 to 3000 fb −1 by around 2035 for ATLAS and CMS. The challenge of coping with the HL-LHC instantaneous and integrated luminosity, along with the associated radiation levels, requires further major changes to the ATLAS detector. The designs are developing rapidly for a new all-silicon tracker, significant upgrades of the calorimeter and muon systems, as well as improved triggers and data acquisition. ATLAS is also examining potential benefits of extensions to larger pseudorapidity, particularly in tracking and muon systems. This report summarizes various improvements to the ATLAS detector required to cope with the anticipated evolution of the LHC luminosity during this decade and the next. A brief overview is also given on physics prospects with a pp centre-of-mass energy of 14 TeV. (paper)

  17. Upgrade of the ATLAS Tile Calorimeter

    CERN Document Server

    Reed, Robert; The ATLAS collaboration

    2014-01-01

    The Tile Calorimeter (TileCal) is the main hadronic calorimeter covering the central region of the ATLAS experiment at LHC. TileCal readout consists of about 10000 channels. The bulk of its upgrade will occur for the High Luminosity LHC operation (Phase 2 around 2023) where the peak luminosity will increase 5x compared to the design luminosity (10^{34} cm^{-2}s^{-1}) but with maintained energy (i.e. 7+7 TeV). The TileCal upgrade aims to replace the majority of the on- and off-detector electronics so that all calorimeter signals can be digitized and directly sent to the off-detector electronics in the counting room. This will reduce pile-up problems and allow more complex trigger algorithms. To achieve the required reliability, redundancy has been introduced at different levels. Three different options are presently being investigated for the front-end electronic upgrade. Extensive test beam studies will determine which option will be selected. 10 Gbps optical links are used to read out all digitized data to t...

  18. Upgrade of the ATLAS Tile Calorimeter

    CERN Document Server

    Moreno, P; The ATLAS collaboration

    2016-01-01

    The Tile Calorimeter (TileCal) is the central hadronic calorimeter covering the central region of the ATLAS experiment at LHC. The TileCal readout consists of about 10000 channels. The bulk of its upgrade will occur for the High Luminosity LHC phase (Phase 2) where the peak luminosity will increase 5$\\times$ compared to the design luminosity ($10^{34} cm^{-2}s^{-1}$) but with maintained energy (i.e. 7+7 TeV). The TileCal upgrade aims at replacing the majority of the on- and off-detector electronics to the extent that all calorimeter signals will be digitized and sent to the off-detector electronics in the counting room. To achieve the required reliability, redundancy has been introduced at different levels. Three different options are presently being investigated for the front-end electronic upgrade. Extensive test beam studies will determine which option will be selected. 10 Gbps optical links are used to read out all digitized data to the counting room while 5 Gbps down-links are used for synchronization, c...

  19. PFM2: a 32 × 32 processor for X-ray diffraction imaging at FELs

    Science.gov (United States)

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

    2016-11-01

    This work is concerned with the design of a readout chip for application to experiments at the next generation X-ray Free Electron Lasers (FEL). The ASIC, named PixFEL Matrix (PFM2), has been designed in a 65 nm CMOS technology and consists of 32 × 32 pixels. Each cell covers an area of 110 × 110 μm2 and includes a low-noise charge sensitive amplifier (CSA) with dynamic signal compression, a time-variant shaper used to process the preamplifier output signal, a 10-bit successive approximation register (SAR) analog-to-digital converter (ADC) and digital circuitry for channel control and data readout. Two different solutions for the readout channel, based on different versions of the time-variant filter, have been integrated in the chip. Both solutions can be operated in such a way to cope with the high frame rate (exceeding 1 MHz) foreseen for future X-ray FEL machines. The ASIC will be bump bonded to a slim/active edge pixel sensor to form the first demonstrator for the PixFEL X-ray imager. This work has been carried out in the frame of the PixFEL project funded by Istituto Nazionale di Fisica Nucleare (INFN), Italy.

  20. X-FEL revolution - X-ray lasers to probe matter

    International Nuclear Information System (INIS)

    Collet, E.; Cammarata, M.; Harmand, M.; Couprie, M.E.

    2015-01-01

    X-ray free electron lasers (X-FEL) are now able to generate X-ray pulses of a few femto-seconds (1 fs = 10"-"1"5 s), which allows the real-time observation of the movements of atoms. The changes in the structure of a material can be seen whatever the material, this is illustrated with the PYP protein (that is the photo-receptor of a bacterium), the changes between an initial state and 100 ps after light excitation show the displacement of the atoms of the protein. The brightness of X-FEL can be so high that it allows the study of nano-metric structures but it enables X-FEL radiation to ionize matter and the crystal sample may be destroyed, this becomes the new limit of X-FEL applied to crystallography. Another application of X-FEL to structure studies is to allow the study of systems that are not crystal systems like macromolecules, proteins or even viruses. Hundreds of patterns of X-ray diffractions of an object are combined to form a 3-dimensional image of the object in the wave vector space and it is then possible but very complex to deduce the real 3-dimensional structure of the object. (A.C.)

  1. Face expressive lifting (FEL): an original surgical concept combined with bipolar radiofrequency.

    Science.gov (United States)

    Divaris, Marc; Blugerman, Guillermo; Paul, Malcolm D

    2014-01-01

    Aging can lead to changes in facial expressions, transforming the positive youth expression of happiness to negative expressions as sadness, tiredness, and disgust. Local skin distension is another consequence of aging, which can be difficult to treat with rejuvenation procedures. The "face expressive lifting" (FEL) is an original concept in facial rejuvenation surgery. On the one hand, FEL integrates established convergent surgical techniques aiming to correct the age-related negative facial expressions. On the other hand, FEL incorporates novel bipolar RF technology aiming to correct local skin distension. One hundred twenty-six patients underwent FEL procedure. Facial expression and local skin distension were assessed with 2 years follow-up. There was a correction of negative facial expression for 96 patients (76 %) and a tightening of local skin distension in 100 % of cases. FEL is an effective procedure taking into account and able to correct both age-related negative changes in facial expression and local skin distension using radiofrequency. Level of Evidence: Level IV, therapeutic study.

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

    International Nuclear Information System (INIS)

    Fawley, William; Vay, Jean-Luc

    2010-01-01

    Numerical electromagnetic simulation of some systems containing charged particles with highly relativistic directed motion can by speeded up by orders of magnitude by choice of the proper Lorentz-boosted frame. A particularly good application for calculation in a boosted frame isthat of short wavelength free-electron lasers (FELs) where a high energy electron beam with small fractional energy spread interacts with a static magnetic undulator. In the optimal boost frame (i.e., the ponderomotive rest frame), the red-shifted FEL radiation and blue-shifted undulator field have identical wavelengths and the number of required longitudinal grid cells and time-steps for fully electromagnetic simulation (relative to the laboratory frame) decrease by factors of gamma 2 each. In theory, boosted frame EM codes permit direct study of FEL problems for which the eikonal approximation for propagation of the radiation field and wiggler-period-averaging for the particle-field interaction may be suspect. We have adapted the WARP code to apply this method to several electromagnetic FEL problems including spontaneous emission, strong exponential gain in a seeded, single pass amplifier configuration, and emission from e-beams in undulators with multiple harmonic components. WARP has a standard relativistic macroparticle mover and a fully 3-D electromagnetic field solver. We discuss our boosted frame results and compare with those obtained using the 'standard' eikonal FEL simulation approach.

  3. Optics

    CERN Document Server

    Fincham, W H A

    2013-01-01

    Optics: Eighth Edition covers the work necessary for the specialization in such subjects as ophthalmic optics, optical instruments and lens design. The text includes topics such as the propagation and behavior of light; reflection and refraction - their laws and how different media affect them; lenses - thick and thin, cylindrical and subcylindrical; photometry; dispersion and color; interference; and polarization. Also included are topics such as diffraction and holography; the limitation of beams in optical systems and its effects; and lens systems. The book is recommended for engineering st

  4. Slum Upgrading and Health Equity.

    Science.gov (United States)

    Corburn, Jason; Sverdlik, Alice

    2017-03-24

    Informal settlement upgrading is widely recognized for enhancing shelter and promoting economic development, yet its potential to improve health equity is usually overlooked. Almost one in seven people on the planet are expected to reside in urban informal settlements, or slums, by 2030. Slum upgrading is the process of delivering place-based environmental and social improvements to the urban poor, including land tenure, housing, infrastructure, employment, health services and political and social inclusion. The processes and products of slum upgrading can address multiple environmental determinants of health. This paper reviewed urban slum upgrading evaluations from cities across Asia, Africa and Latin America and found that few captured the multiple health benefits of upgrading. With the Sustainable Development Goals (SDGs) focused on improving well-being for billions of city-dwellers, slum upgrading should be viewed as a key strategy to promote health, equitable development and reduce climate change vulnerabilities. We conclude with suggestions for how slum upgrading might more explicitly capture its health benefits, such as through the use of health impact assessment (HIA) and adopting an urban health in all policies (HiAP) framework. Urban slum upgrading must be more explicitly designed, implemented and evaluated to capture its multiple global environmental health benefits.

  5. Upgrade trigger: Biannual performance update

    CERN Document Server

    Aaij, Roel; Couturier, Ben; Esen, Sevda; De Cian, Michel; De Vries, Jacco Andreas; Dziurda, Agnieszka; Fitzpatrick, Conor; Fontana, Marianna; Grillo, Lucia; Hasse, Christoph; Jones, Christopher Rob; Le Gac, Renaud; Matev, Rosen; Neufeld, Niko; Nikodem, Thomas; Polci, Francesco; Del Buono, Luigi; Quagliani, Renato; Schwemmer, Rainer; Seyfert, Paul; Stahl, Sascha; Szumlak, Tomasz; Vesterinen, Mika Anton; Wanczyk, Joanna; Williams, Mark Richard James; Yin, Hang; Zacharjasz, Emilia Anna

    2017-01-01

    This document presents the performance of the LHCb Upgrade trigger reconstruction sequence, incorporating changes to the underlying reconstruction algorithms and detector description since the Trigger and Online Upgrade TDR. An updated extrapolation is presented using the most recent example of an Event Filter Farm node.

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

    Science.gov (United States)

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

    2016-09-01

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

  7. Upgrade of the ATLAS Tile Calorimeter Electronics

    International Nuclear Information System (INIS)

    Carrió, F

    2015-01-01

    The Tile Calorimeter (TileCal) is the hadronic calorimeter covering the central region of the ATLAS experiment at LHC. The TileCal readout consists of about 10000 channels. The bulk of its upgrade will occur for the High Luminosity LHC phase (Phase-II) where the peak luminosity will increase 5 times compared to the design luminosity (10 34 cm −2 s −1 ) but with maintained energy (i.e. 7+7 TeV). An additional increase of the average luminosity with a factor of 2 can be achieved by luminosity levelling. This upgrade is expected to happen around 2024. The TileCal upgrade aims at replacing the majority of the on- and off- detector electronics to the extent that all calorimeter signals will be digitized and sent to the off-detector electronics in the counting room. To achieve the required reliability, redundancy has been introduced at different levels. Three different options are presently being investigated for the front-end electronic upgrade. Extensive test beam studies will determine which option will be selected. 10 Gbps optical links are used to read out all digitized data to the counting room while 5 Gbps down-links are used for synchronization, configuration and detector control. For the off-detector electronics a pre-processor (sROD) is being developed, which takes care of the initial trigger processing while temporarily storing the main data flow in pipeline and derandomizer memories. One demonstrator prototype module with the new calorimeter module electronics, but still compatible with the present system, is planned to be inserted in ATLAS this year

  8. Upgrading the ATLAS control system

    International Nuclear Information System (INIS)

    Munson, F.H.; Ferraretto, M.

    1993-01-01

    Heavy-ion accelerators are tools used in the research of nuclear and atomic physics. The ATLAS facility at the Argonne National Laboratory is one such tool. The ATLAS control system serves as the primary operator interface to the accelerator. A project to upgrade the control system is presently in progress. Since this is an upgrade project and not a new installation, it was imperative that the development work proceed without interference to normal operations. An additional criteria for the development work was that the writing of additional ''in-house'' software should be kept to a minimum. This paper briefly describes the control system being upgraded, and explains some of the reasons for the decision to upgrade the control system. Design considerations and goals for the new system are described, and the present status of the upgrade is discussed

  9. LHC luminosity upgrade detector challenges

    CERN Multimedia

    CERN. Geneva; de Roeck, Albert; Bortoletto, Daniela; Wigmans, Richard; Riegler, Werner; Smith, Wesley H

    2006-01-01

    LHC luminosity upgrade: detector challenges The upgrade of the LHC machine towards higher luminosity (1035 cm -2s-1) has been studied over the last few years. These studies have investigated scenarios to achieve the increase in peak luminosity by an order of magnitude, as well as the physics potential of such an upgrade and the impact of a machine upgrade on the LHC DETECTORS. This series of lectures will cover the following topics: • Physics motivation and machine scenarios for an order of magnitude increase in the LHC peak luminosity (lecture 1) • Detector challenges including overview of ideas for R&D programs by the LHC experiments: tracking and calorimetry, other new detector developments (lectures 2-4) • Electronics, trigger and data acquisition challenges (lecture 5) Note: the much more ambitious LHC energy upgrade will not be covered

  10. The DarkLight Experiment at the JLab FEL

    Science.gov (United States)

    Fisher, Peter

    2013-10-01

    DarkLight will study the production of gauge bosons associated with Dark Forces theories in the scattering of 100 MeV electrons on proton a target. DarkLight is a spectrometer to measure all the final state particles in e- + p -->e- + p +e- +e+ . QED allows this process and the invariant mass distribution of the e+e- pair is a continuum from nearly zero to nearly the electron beam energy. Dark Forces theories, which allow the dark matter mass scale to be over 1 TeV, predict a gauge boson A' in the mass range of 10-1,000 MeV and decays to an electron-positron pair with an invariant mass of mA'. We aim to search for this process using the 100 MeV, 10 mA electron beam at the JLab Free Electron Laser impinging on a hydrogen target with a 1019 cm-2 density. The resulting luminosity of 6 ×1035/cm2-s gives the experiment enough sensitivity to probe A' couplings of 10-9 α . DarkLight is unique in its design to detect all four particles in the final state. The leptons will be measured in a large high-rate TPC and a silicon sensor will measure the protons. A 0.5 T solenoidal magnetic field provides the momentum resolution and focuses the copious Møller scattering background down the beam line, away from the detectors. A first beam test has shown the FEL beam is compatible with the target design and that the hall backgrounds are manageable. The experiment has been approved by Jefferson Lab for first running in 2017.

  11. The Fermilab ACNET upgrade

    International Nuclear Information System (INIS)

    Briegel, C.; Johnson, G.; Winterowd, L.

    1990-01-01

    The Fermilab Accelerator Controls Network (ACNET) upgrade consists of a new physical medium (IEEE 802.5 token ring), additions to the calling sequence and added processor support. ACNET is the accelerator control backbone network for all data communication. A proprietary network was replaced by an IEEE standard enabling an open network with excellent characteristics for the control system. The calling sequence was enhanced for the added capabilities of the token-ring interface such as 'gather-read' and 'scatter-write'. In addition to prior support of DEC PDP11s under RS11M and VAXs under VMS, the ACNET calling sequence was implemented in the language C for the IBM PC with MS-DOS and Motorola 680x0 with MTOS using VME bus. Additional support is in progress for Intel 80x86 with MTOS using Multibus II. (orig.)

  12. ISTTOK control system upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Ivo S., E-mail: ivoc@ipfn.ist.utl.pt; Duarte, Paulo; Fernandes, Horácio; Valcárcel, Daniel F.; Carvalho, Pedro J.; Silva, Carlos; Duarte, André S.; Neto, André; Sousa, Jorge; Batista, António J.N.; Carvalho, Bernardo B.

    2013-10-15

    Highlights: •ISTTOK fast controller. •All real-time diagnostic and actuators were integrated in the control platform. •100 μs control cycle under the MARTe framework. •The ISTTOK control system upgrade provides reliable operation with an improved operational space. -- Abstract: The ISTTOK tokamak (Ip = 4 kA, BT = 0.5 T, R = 0.46 m, a = 0.085 m) is one of the few tokamaks with regular alternate plasma current (AC) discharges scientific programme. In order to improve the discharge stability and to increase the number of AC discharge cycles a novel control system was developed. The controller acquires data from 50 analog-to-digital converter (ADC) channels of real-time diagnostics and measurements: tomography, Mirnov coils, interferometer, electric probes, sine and cosine probes, bolometer, current delivered by the power supplies, loop voltage and plasma current. The system has a control cycle of 100 μs during which it reads all the diagnostics connected to the advanced telecommunications computing architecture (ATCA) digitizers and sends the control reference to ISTTOK actuators. The controller algorithms are executed on an Intel{sup ®} Q8200 chip with 4 cores running at 2.33 GHz and connected to the I/O interfaces through an ATCA based environment. The real-time control system was programmed in C++ on top of the Multi-threaded Application Real-Time executor (MARTe). To extend the duration of the AC discharges and the plasma stability a new magnetising field power supply was commissioned and the horizontal and vertical field power supplies were also upgraded. The new system also features a user-friendly interface based on HyperText Markup Language (HTML) and Javascript to configure the controller parameters. This paper presents the ISTTOK control system and the consequent update of real-time diagnostics and actuators.

  13. ISTTOK control system upgrade

    International Nuclear Information System (INIS)

    Carvalho, Ivo S.; Duarte, Paulo; Fernandes, Horácio; Valcárcel, Daniel F.; Carvalho, Pedro J.; Silva, Carlos; Duarte, André S.; Neto, André; Sousa, Jorge; Batista, António J.N.; Carvalho, Bernardo B.

    2013-01-01

    Highlights: •ISTTOK fast controller. •All real-time diagnostic and actuators were integrated in the control platform. •100 μs control cycle under the MARTe framework. •The ISTTOK control system upgrade provides reliable operation with an improved operational space. -- Abstract: The ISTTOK tokamak (Ip = 4 kA, BT = 0.5 T, R = 0.46 m, a = 0.085 m) is one of the few tokamaks with regular alternate plasma current (AC) discharges scientific programme. In order to improve the discharge stability and to increase the number of AC discharge cycles a novel control system was developed. The controller acquires data from 50 analog-to-digital converter (ADC) channels of real-time diagnostics and measurements: tomography, Mirnov coils, interferometer, electric probes, sine and cosine probes, bolometer, current delivered by the power supplies, loop voltage and plasma current. The system has a control cycle of 100 μs during which it reads all the diagnostics connected to the advanced telecommunications computing architecture (ATCA) digitizers and sends the control reference to ISTTOK actuators. The controller algorithms are executed on an Intel ® Q8200 chip with 4 cores running at 2.33 GHz and connected to the I/O interfaces through an ATCA based environment. The real-time control system was programmed in C++ on top of the Multi-threaded Application Real-Time executor (MARTe). To extend the duration of the AC discharges and the plasma stability a new magnetising field power supply was commissioned and the horizontal and vertical field power supplies were also upgraded. The new system also features a user-friendly interface based on HyperText Markup Language (HTML) and Javascript to configure the controller parameters. This paper presents the ISTTOK control system and the consequent update of real-time diagnostics and actuators

  14. Development of an alternative testing strategy for the fish early life-stage (FELS) test using the AOP framework

    Science.gov (United States)

    Currently, the fish early life-stage (FELS) test (OECD 210) is the primary guideline used to estimate chronic toxicity of regulated chemicals. Although already more cost-efficient than adult fish tests, the FELS test has some important drawbacks. Both industry and regulatory inst...

  15. Scientific opportunities for FEL amplifier based VUV and X-ray research

    International Nuclear Information System (INIS)

    Johnson, E.D.

    1994-01-01

    It has become increasingly clear to a wide cross section of the synchrotron radiation research community that FELs will be the cornerstone of Fourth Generation Radiation Sources. Through the coherent generation of radiation, they provide as much as 12 orders of magnitude increase in peak power over the third generation storage ring machines of today. Facilities have been proposed which will extend the operating wavelength of these devices well beyond the reach of existing solid state laser technology. In addition, it appears possible to generate pulses of unprecedented brevity, down to a few femtoseconds, with mJ pulse energies. The combination of these attributes has stimulated considerable interest in short wavelength FELs for experiments in chemical, surface, and solid state physics, biology and materials science. This paper provides a brief overview of how the features of these FEL's relate to the experimental opportunities

  16. IR-FEL-induced green fluorescence protein (GFP) gene transfer into plant cell

    CERN Document Server

    Awazu, K; Tamiya, E

    2002-01-01

    A Free Electron Laser (FEL) holds potential for various biotechnological applications due to its characteristics such as flexible wavelength tunability, short pulse and high peak power. We could successfully introduce the Green Fluorescent Protein (GFP) gene into tobacco BY2 cells by IR-FEL laser irradiation. The irradiated area of the solution containing BY2 cells and plasmid was about 0.1 mm sup 2. FEL irradiation at a wavelength of 5.75 and 6.1 mu m, targeting absorption by the ester bond of the lipid and the amide I bond of the protein, respectively, was shown to cause the introduction of the fluorescent dye into the cell. On the other hand, transient expression of the GFP fluorescence was only observed after irradiation at 5.75 mu m. The maximum transfer efficiency was about 0.5%.

  17. A photocathode rf gun design for a mm-wave linac-based FEL

    Energy Technology Data Exchange (ETDEWEB)

    Nassiri, A.; Berenc, T,; Foster, J.; Waldschmidt, G.; Zhou, J.

    1995-07-01

    In recent years, advances in the rf gun technology have made it possible to produce small beam emittances suitable for short period microundulators which take advantage of the low emittance beam to reduce the wavelength of FELs. At the Advanced Photon Source, we are studying the design of a compact 50-MeV superconducting mm-wave linac-based FEL for the production of short wavelengths ({approximately}300 nm) to carry out FEL demonstration experiments. The electron source considered for the linac is a 30- GHz, 3 1/2-cell {pi}-mode photocathode rf gun. For cold model rf measurements a 15-GHz prototype structure was fabricated. Here we report on the design, numerical modelling and the initial cold-model rf measurement results on the 15-GHz prototype structure.

  18. A photocathode rf gun design for a mm-wave linac-based FEL

    International Nuclear Information System (INIS)

    Nassiri, A.; Berenc, T.; Foster, J.; Waldschmidt, G.; Zhou, J.

    1995-01-01

    In recent years, advances in the rf gun technology have made it possible to produce small beam emittances suitable for short period microundulators which take advantage of the low emittance beam to reduce the wavelength of FELs. At the Advanced Photon Source, we are studying the design of a compact 50-MeV superconducting mm-wave linac-based FEL for the production of short wavelengths (∼300 nm) to carry out FEL demonstration experiments. The electron source considered for the linac is a 30- GHz, 3 1/2-cell π-mode photocathode rf gun. For cold model rf measurements a 15-GHz prototype structure was fabricated. Here we report on the design, numerical modelling and the initial cold-model rf measurement results on the 15-GHz prototype structure

  19. Suppression of mode-beating in a saturated hole-coupled FEL oscillator

    International Nuclear Information System (INIS)

    Krishnagopal, S.; Xie, M.; Kim, K.J.

    1992-08-01

    In a hole-coupled resonator, either empty or loaded with a linear FEL gain medium, the phenomenon of mode-degeneracy and mode-beating have been studied. When the magnitudes of the eigenvalues, derived from a linear analysis, are equal for two or more dominant eigenmodes, the system cannot achieve a stable beam-profile. We investigate this phenomenon when a saturated FEL is present within the cavity, thus introducing non-linearity. We use a three-dimensional FEL oscillator code, based on the amplifier code TDA, and show that mode-beating is completely suppressed in the nonlinear saturated regime. We suggest a simple, qualitative model for the mechanism responsible for this suppression

  20. Analyses of superradiance and spiking-mode lasing observed at JAERI-FEL

    CERN Document Server

    Hajima, R; Nagai, R; Minehara, E J

    2001-01-01

    Japan Atomic Energy Research Institute (JAERI)-FEL has achieved quasi-CW lasing with an average power of 1.7 kW, the initial goal of the R and D program. The FEL extraction efficiency obtained completely exceeds the well-known limit for non-bunched beam, which is determined by the number of undulator periods. We have conducted numerical studies to characterize lasing dynamics observed at JAERI-FEL. Cavity-length detuning curves numerically obtained show good agreement with experimental results. Lasing behavior numerically obtained exhibits chaotic spiking-mode and superradiance as the cavity-length detuning approaches zero. Broadening of lasing spectrum observed in the experiments is explained by these lasing dynamics. The extraction efficiency becomes maximal at the perfect synchronization of the cavity length, where the lasing is quasi-stationary superradiance. We also compare these results with analytical theory previously reported.

  1. SOFT X-RAY FEL BY CASCADING STAGES OF HIGH GAIN HARMONIC GENERATION.

    Energy Technology Data Exchange (ETDEWEB)

    YU,L.H.

    2003-04-17

    Short wavelength Free-Electron Lasers are perceived as the next generation of synchrotron light sources. In the past decade, significant advances have been made in the theory and technology of high brightness electron beams and single pass FELs. These developments facilitate the construction of practical VUV FELs and make x-ray FELs possible. Self-Amplified Spontaneous Emission (SASE) and High Gain Harmonic Generation (HGHG)[17-19] are the two leading candidates for x-ray FELs. The first lasing of HGHG proof-of-principle experiment succeeded in August, 1999 in Brookhaven National Laboratory. The experimental results agree with the theory prediction. Compared with SASE FEL, the following advantages of HGHG FEL were confirmed; (1) Better longitudinal coherence, and hence, much narrower bandwidth than SASE. (2) More stable central wavelength, (3) More stable output energy. In this introduction, we will first briefly describe the principle of HGHG in Section A. Then in Section B, we give a general description about how to produce soft x-ray by cascading HGHG scheme. In section 2, we give a detailed description of the system design. Then, in section 3, we give a description of an analytical estimate for the HGHG process, and the calculation of the parameters of different parts of the system. The estimate is found to agree with simulation within about a factor 2 for most cases we studied. The stability issue, the sensitivity to parameter variation, the harmonic contents of the final output, and the noise degradation issue of such HGHG scheme are discussed in Section 4. The results are presented in Section 4. Finally, in Section 5, we will give some discussion of the challenges in development of the system. The conclusion is given in Section 6.

  2. Status of FEL-SUT project, and the experimental setup for multiphoton dissociation and isotope separation in the gaseous phase

    CERN Document Server

    Chernyshev, A V; Petrov, A K; Kawai, M; Toyoda, K; Nakai, K; Kuroda, H

    2001-01-01

    The IR FEL Research Center of the Science University of Tokyo (FEL-SUT) is open for users to develop new applications of IR FEL in a wide field of material science, chemical technology and bio-chemical applications. The FEL is based on 35 MeV linac operated at the frequency of 2856 MHz (s-band). The FEL covers the wavelength range from 5 to 16 mu m with the micropulse duration of 1-2 ps, macropulse duration of 1 mu s, macropulse repetition rate of 10 Hz and the overall average power of 1 W. We report the present status of the Center and an experimental setup designed and constructed for the experiments on multiphoton dissociation and isotope separation.

  3. Gain length dependence on phase shake in the VUV-FEL at the TESLA Test Facility

    Energy Technology Data Exchange (ETDEWEB)

    Pflueger, J. [DESY/HASYLAB, Hamburg (Germany); Schneidmiller, E.A. [Automatic Systems Corporation, Samara (Russian Federation); Pierini, P. [INFN, Milano (Italy)

    1995-12-31

    The TTF VUV FEL, which is in its design stage at DESY, consists of a 30 m long SASE FEL which will radiate around 6 nm, driven by a superconducting linac with final energy of 1 GeV. One of the important issues in its design is the undulator performance, which is studied in this paper. The present setup, including FODO lattice, is discussed in this paper. Results of simulations, including the realistic wiggler field errors and beam stearing, are presented. Dependence of the performance, in particular the gain and saturation length as well as the saturation peak power, on the wiggler field errors is discussed.

  4. A high-power rf linear accelerator for FELS [free-electron lasers

    International Nuclear Information System (INIS)

    Sheffield, R.L.; Watson, J.M.

    1987-01-01

    This paper describes the design of a high average current rf linear accelerator suitable for driving short-wavelength free-electron lasers (FEL). It is concluded that the design of a room-temperature rf linear acelerator that can meet the stringent requirements of a high-power short-wavelength FEL appears possible. The accelerator requires the use of an advanced photoelectric injector that is under development; the accelerator components, however, do not require appreciable development. At these large beam currents, low-frequency, large-bore room-temperature cavities can be highly efficient and give all specified performance with minimal risk. 20 refs

  5. FEL research and development at the SLAC sub-picosecond photon source, SPPS

    International Nuclear Information System (INIS)

    Bentson, L.; Bolton, P.; Bong, E.; Emma, P.; Galayda, J.; Hastings, J.; Krejcik, P.; Rago, C.; Rifkin, J.; Spencer, C.M.

    2003-01-01

    An upgrade project to the SLAC linac allows ultra-short electron bunches to be interleaved with the routine high-energy physics program operation, for use with an undulator to produce short-pulse, high-brightness X-rays. The linac upgrade comprises of the installation in the summer of 2002 of a bunch compressor chicane of similar design to the Linac Coherent Light Source (LCLS) project. A final compression stage in the high-energy Final Focus Test Beam (FFTB) line compresses the 28 GeV, 3.4 nC electron bunch to 80 fs FWHM, where a 5 m section of undulator (K=4.45) will produce 1.5 A X-rays with 3x10 7 photons per pulse and a peak brightness of 4x10 24 photons mm -2 mrad -2 s -1 (0.1% BW). The facility will allow us to test the dynamics and associated technology of bunch compression and gain valuable experience for the LCLS using the SLAC linac. New ultra-short electron bunch diagnostic techniques will be developed hand in hand with the same ultra-fast laser technology to be used for LCLS. Issues of high peak power (27 GW) X-ray transport and optics can be addressed at this facility as well as pump-probe and ultra-fast laser timing and stability issues

  6. Photoionization of atoms and molecules by intense EUV-FEL pulses and FEL seeded by high-order harmonic of ultrashort laser pulses

    International Nuclear Information System (INIS)

    Iwasaki, Atsushi; Owada, Shigeki; Yamanouchi, Kaoru; Sato, Takahiro; Nagasono, Mitsuru; Yabashi, Makina; Ishikawa, Tetsuya; Togashi, Tadashi; Takahashi, Eiji J.; Midorikawa, Katsumi; Aoyama, Makoto; Yamakawa, Koichi; Kannari, Fumihiko; Yagishita, Akira

    2012-01-01

    The advantages of SPring-8 Compact SASE Source as a light source for spectroscopic measurements in the extreme ultraviolet (EUV) wavelength region are introduced by referring to our recent study of non-linear photoionization processes of He, in which the absolute two-photon ionization cross sections of He at four different wavelengths in the 54 - 62 nm region were determined using intense pulses of the free-election laser (FEL). In addition, our recent effort to generate intense full-coherent EUV light pulses are introduced, in which significant amplification of the 13th harmonic of ultrashort laser pulses at 800 nm was achieved by FEL seeded with the 13th harmonic. (author)

  7. PixFEL: developing a fine pitch, fast 2D X-ray imager for the next generation X-FELs

    International Nuclear Information System (INIS)

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

    2015-01-01

    The PixFEL project is conceived as the first stage of a long term research program aiming at the development of advanced X-ray imaging instrumentation for applications at the free electron laser (FEL) facilities. The project aims at substantially advancing the state-of-the-art in the field of 2D X-ray imaging by exploring cutting-edge solutions for sensor development, for integration processes and for readout channel architectures. The main focus is on the development of the fundamental microelectronic building blocks for detector readout and on the technologies for the assembly of a multilayer module with minimum dead area. This work serves the purpose of introducing the main features of the project, together with the simulation results leading to the first prototyping run

  8. H-1 Upgrades (4BW/4BN) (H-1 Upgrades)

    Science.gov (United States)

    2015-12-01

    automatic blade fold of the new composite rotor blades, new performance matched transmissions, a new four-bladed tail rotor and drive system, upgraded...Upgrades December 2015 SAR March 18, 2016 10:59:17 UNCLASSIFIED 4 Col Steven Girard PMA-276 USMC Light/Attack Helicopter Program Executive Officer...attack helicopter is to provide rotary wing close air support, anti-armor, armed escort, armed/visual reconnaissance and fire support coordination

  9. Upgrade of the CSC Endcap Muon Port Card at CMS

    International Nuclear Information System (INIS)

    Matveev, M; Padley, P

    2010-01-01

    The Muon Port Card (MPC) provides optical transmission of Level 1 Trigger primitives from 60 Endcap peripheral crates to the Track Finder (TF) crate within the CMS Cathode Strip Chamber (CSC) sub-detector at the CMS experiment at CERN. The system has been in operation since 2008 and comprises 180 1.6 Gbps optical links. The proposed Super-LHC (SLHC) upgrade implies higher data volumes to be transmitted through the trigger chain and more sophisticated trigger algorithms. We expect to upgrade the MPC boards within the next few years to accommodate these requirements. The paper presents the first results of simulation and prototyping with the goal of improving the sorting algorithms and using parallel 12-channel optical links and a more powerful Virtex-5 FPGA.

  10. An optical parametric chirped-pulse amplifier for seeding high repetition rate free-electron lasers

    International Nuclear Information System (INIS)

    Höppner, H; Hage, A; Tanikawa, T; Schulz, M; Faatz, B; Riedel, R; Prandolini, M J; Teubner, U; Tavella, F

    2015-01-01

    High repetition rate free-electron lasers (FEL), producing highly intense extreme ultraviolet and x-ray pulses, require new high power tunable femtosecond lasers for FEL seeding and FEL pump-probe experiments. A tunable, 112 W (burst mode) optical parametric chirped-pulse amplifier (OPCPA) is demonstrated with center frequencies ranging from 720–900 nm, pulse energies up to 1.12 mJ and a pulse duration of 30 fs at a repetition rate of 100 kHz. Since the power scalability of this OPCPA is limited by the OPCPA-pump amplifier, we also demonstrate a 6.7–13.7 kW (burst mode) thin-disk OPCPA-pump amplifier, increasing the possible OPCPA output power to many hundreds of watts. Furthermore, third and fourth harmonic generation experiments are performed and the results are used to simulate a seeded FEL with high-gain harmonic generation. (paper)

  11. The Atlas upgrade project

    International Nuclear Information System (INIS)

    Bollinger, L.M.

    1988-01-01

    ATLAS is a heavy-ion accelerator system consisting of a 9-MV tandem electrostatic injector coupled to a superconducting linac. A project now well advanced will upgrade the capabilities of ATLAS immensely by replacing the tandem and its negative-ion source with a positive-ion injector that consists of an electron-cyclotron resonance (ECR) ion source and a 12-MV superconducting injector linac of novel design. This project will increase the beam intensity 100 fold and will extend the projectile-mass range up to uranium. Phase 1 of the work, which is nearing completion in late 1988, will provide an injector comprising the ECR source and its 350-kV voltage platform, beam analysis and bunching systems, beam lines, and a prototype 3-MV linac. The ECR source and its voltage platform are operational, development of the new class of low-frequency interdigital superconducting resonators required for the injector linac has been completed, and assembly of the whole system is in progress. Test runs and then routine use of the Phase 1 injector systems are planned for early 1989, and the final 12-MV injector linac will be commissioned in 1990. 12 refs., 6 figs

  12. Superhilac upgrade project

    International Nuclear Information System (INIS)

    Feinberg, B.; Brown, I.G.

    1985-05-01

    This project will increase the uranium output of the Bevalac heavy-ion facility from the currently available 10 7 to 5 x 10 7 ions/pulse, allowing accurate Lamb shift measurements to be made in U 90+ and U 91+ with important applications to the testing of quantum electrodynamics and the development of an x-ray laser. The injected beam intensity will be increased to make better use of the 10emA output space-charge limit of the Wideroe linac. Components will include a new high current MEtal Vapor Vacuum Arc (MEVVA) ion source along with an improved high current, high voltage Cockcroft-Walton power supply to handle the increased beam current. The Low Energy Beam Transport (LEBT) line will be upgraded with additional focusing to manage the increased space-charge forces and with an improved vacuum to reduce charge exchange losses. Finally, the phase matching between the 23MHz Wideroe linac and the 70MHz Alvarez linac will be improved by the addition of the appropriate buncher cavities. Physics design is underway and detailed engineering is scheduled to begin in October 1985, with installation slated for the 1986 summer shutdown

  13. Alberta propylene upgrading prospects

    International Nuclear Information System (INIS)

    2000-03-01

    A very significant byproduct recovery and purification scheme is at present being prepared by TransCanada Midstream (TCMS). Alberta Economic Development commissioned an independent study to identify propylene supply options while proceeding with the evaluation of various propylene derivatives with regard to their fit with the Alberta context. Identification of chemical companies with derivative interests was also accomplished. By 2005, it is estimated that 280 kilo-tonnes of propylene will be available on an annual basis from byproduct sources. Those sources are oil sands upgraders, ethylene plants and refineries. The ranges of impurities and supply costs vary between the different sources. An option being considered involves pipeline and rail receipt with a major central treating and distillation facility for the production of polymer grade (PG) propylene with propane and other smaller byproducts. Special consideration was given to three chemicals in this study, namely: polypropylene (PP), acrylonitrile (ACN), and acrylic acid (AA). Above average growth rates were identified for these chemicals: demand is growing at 6 to 7 per cent a year for both PP and ACN, while demand for AA grows at 8 per cent annually. Two other possibilities were identified, propylene oxide (PO) and phenol. The study led to the conclusion that low capital and operating costs and shipping costs to the Pacific Rim represent advantages to the development of propylene derivatives in the future in Alberta. 4 refs., 87 tabs., 7 figs

  14. Mongolia - Vocational Education - Equipment Upgrades

    Data.gov (United States)

    Millennium Challenge Corporation — Evaluation design The impact evaluation sought to identify the causal impact of exposure to equipment upgrades on subsequent outcomes. Insofar as we were not able to...

  15. Mining Upgrades to Reduce Pollution

    Science.gov (United States)

    Settlement with Southern Coal Corporation and 26 affiliates requires the companies to comprehensively upgrade their coal mining and processing operations to prevent polluted wastewater from threatening rivers and streams and communities across Appalachia.

  16. Silicon Tracking Upgrade at CDF

    International Nuclear Information System (INIS)

    Kruse, M.C.

    1998-04-01

    The Collider Detector at Fermilab (CDF) is scheduled to begin recording data from Run II of the Fermilab Tevatron in early 2000. The silicon tracking upgrade constitutes both the upgrade to the CDF silicon vertex detector (SVX II) and the new Intermediate Silicon Layers (ISL) located at radii just beyond the SVX II. Here we review the design and prototyping of all aspects of these detectors including mechanical design, data acquisition, and a trigger based on silicon tracking

  17. WNP-2 core model upgrade

    International Nuclear Information System (INIS)

    Golightly, C.E.; Ravindranath, T.K.; Belblidia, L.A.; O'Farrell, D.; Andersen, P.S.

    2006-01-01

    The paper describes the core model upgrade of the WNP-2 training simulator and the reasons for the upgrade. The core model as well as the interface with the rest of the simulator are briefly described . The paper also describes the procedure that will be used by WNP-2 to update the simulator core data after future core reloads. Results from the fully integrated simulator are presented. (author)

  18. Commissioning and Operational Experience With an Intermediate Upgrade Cryomodule for the CEBAF 12 GeV Upgrade

    International Nuclear Information System (INIS)

    Thomas Powers; Davis, G.; Michael Drury; Christiana Grenoble; Hovater, J.; Lawrence King; Tomasz Plawski; Joseph Preble

    2005-01-01

    Three cryomodules have been designed and built as intermediate prototypes for the CEBAF 12 GeV upgrade. This paper will discuss the commissioning and operational experience with the second of these cryomodules, which was installed and commissioned in the Jefferson Lab 10 kW Free Electron Laser Facility. Within the cryomodule are eight 7-cell, 1497 MHz cavities. It was designed to accelerate 1 mA of beam in excess of 70 MV and to have the same footprint as a standard CEBAF cryomodule. The cryomodule was installed in parallel with the FEL beam line in the spring of 2004 and characterized simultaneous with beam delivery. It was installed in the beam line in the early summer of 2004 and has since been operated as part of an energy recovered linac with 5 mA of beam current and 75 MV accelerating gradient for extended periods of time. Additionally, it was operated at 1 mA of beam current and 80 MV of accelerating gradient for several hours without a trip. In the latter operating mode the beam current was limited by the injector setup

  19. ATLAS calorimeter and topological trigger upgrades for Phase 1

    CERN Document Server

    Silverstein, S

    2011-01-01

    The ATLAS Level-1 Calorimeter Trigger (L1Calo) collaboration is pursuing two hardware upgrade programs for Phase 1 of the LHC upgrade. The first of these is development of a new mixed-signal multi-chip module (MCM) for the PreProcessor system. based on faster FADCs and a modern FPGA. Designed as a drop-in replacement for the existing MCM, the FPGA also enables future upgrades to the PreProcessor algorithms, including enhanced digital filtering and compensation for time-variation of pedestals. It is also planned to augment the current multiplicity-based trigger by adding topology-based algorithms. This is made possible by adding jet and EM/hadron Regions of Interest (ROIs) to the L1Calo real time data path. A synchronous, pipelined topological processor (TP) based on high-density FPGAs and multi-Gbit optical links gathers all ROI information and performs topological algorithms.

  20. Setting priorities for safeguards upgrades

    International Nuclear Information System (INIS)

    Al-Ayat, R.A.; Judd, B.R.; Patenaude, C.J.; Sicherman, A.

    1987-01-01

    This paper describes an analytic approach and a computer program for setting priorities among safeguards upgrades. The approach provides safeguards decision makers with a systematic method for allocating their limited upgrade resources. The priorities are set based on the upgrades cost and their contribution to safeguards effectiveness. Safeguards effectiveness is measured by the probability of defeat for a spectrum of potential insider and outsider adversaries. The computer program, MI$ER, can be used alone or as a companion to ET and SAVI, programs designed to evaluate safeguards effectiveness against insider and outsider threats, respectively. Setting the priority required judgments about the relative importance (threat likelihoods and consequences) of insider and outsider threats. Although these judgments are inherently subjective, MI$ER can analyze the sensitivity of the upgrade priorities to these weights and determine whether or not they are critical to the priority ranking. MI$ER produces tabular and graphical results for comparing benefits and identifying the most cost-effective upgrades for a given expenditure. This framework provides decision makers with an explicit and consistent analysis to support their upgrades decisions and to allocate the safeguards resources in a cost-effective manner

  1. Development of intense terahertz coherent synchrotron radiation at KU-FEL

    Energy Technology Data Exchange (ETDEWEB)

    Sei, Norihiro, E-mail: sei.n@aist.go.jp [Research Institute for Measurement and Analytical Instrumentation, National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Umezono, Tsukuba, Ibaraki 305-8568 (Japan); Zen, Heishun; Ohgaki, Hideaki [Institute for Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan)

    2016-10-01

    We produced intense coherent synchrotron radiation (CSR) in the terahertz (THz) region using an S-band linac at the Kyoto University Free Electron Laser (KU-FEL), which is a mid-infrared free-electron laser facility. The CSR beam was emitted from short-pulse electron bunches compressed by a 180° arc, and was transferred to air at a large solid angle of 0.10 rad. The measured CSR energy was 55 μJ per 7 μs macropulse, and KU-FEL was one of the most powerful CSR sources in normal conducting linear accelerator facilities. The CSR spectra were measured using an uncooled pyroelectric detector and a Michelson-type interferometer designed specifically for the KU-FEL electron beam, and had a maximum at a frequency of 0.11 THz. We found that adjusting the energy slit enhanced the CSR energy and shortened the electron beam bunch length in the CSR spectra measurements. Our results demonstrated that the efficient use of the energy slit can help improve the characteristics of CSR. - Highlights: • We have developed intense coherent synchrotron radiation (CSR) at KU-FEL. • The elevation angle of the CSR was correctly measured by a new technique. • The CSR power extracted to the air was 55 μJ per 7 μs macropulse. • It was demonstrated that an energy slit was effective to improve the CSR properties.

  2. Experimental results of two stage harmonic generation with picosecond pulses on the Stanford Mark III FEL

    International Nuclear Information System (INIS)

    Hooper, B.A.; Utah Univ., Salt Lake City; Stanford Univ., CA; Benson, S.V.; Madey, M.J.; Cutolo, A.; Naples Univ.

    1988-01-01

    We report experimental results on upper harmonic conversion using a lithium niobate and a beta barium borate crystal to quadruple the FEL light up into the visible and near infrared. The effects of finite linewidth, birefringent walk-off, and group velocity walk-off on conversion efficiency will be discussed with reference to the experimental results. (orig.)

  3. Magnetic measurement, sorting optimization and adjustment of SDUV-FEL hybrid undulator

    International Nuclear Information System (INIS)

    Wang Tao; Jia Qika

    2007-01-01

    Construction of an undulator includes magnet block measurement, sorting, field measurement and adjustment. Optimizing SDUV-FEL undulator by simulated annealing algorithm using measurement results of the magnet blocks by Helmholtz coil before installing undulator magnets, the cost function can be reduced by three orders of magnitude. The practical parameters of one segment meet the design specifications after adjusting the magnetic field. (authors)

  4. Start-To-End Simulations of the Energy Recovery Linac Prototype FEL

    CERN Document Server

    Gerth, Christopher; Muratori, Bruno; Owen, Hywel; Thompson, Neil R

    2004-01-01

    Daresbury Laboratory is currently building an Energy Recovery Linac Prototype (ERLP) that serves as a testbed for the study of beam dynamics and accelerator technology important for the design and construction of the proposed 4th Generation Light Source (4GLS) project. Two major objectives for the ERLP are the operation of an oscillator infra-red FEL and demonstration of energy recovery from an electron bunch with an energy spread induced by the FEL. In this paper we present start-to-end simulations including the FEL of the ERLP. The beam dynamics in the high-brightness injector, which consists of a DC photocathode gun and a super-conducting booster, have been modelled using the particle tracking code ASTRA. After the main linac, in which the particles are accelerated to 35 MeV, particles have been tracked with the code ELEGANT. The 3D code GENESIS was used to model the FEL interaction with the electron beam. Different modes of operation and their impact on the design of the ERLP are discussed.

  5. Development of intense terahertz coherent synchrotron radiation at KU-FEL

    International Nuclear Information System (INIS)

    Sei, Norihiro; Zen, Heishun; Ohgaki, Hideaki

    2016-01-01

    We produced intense coherent synchrotron radiation (CSR) in the terahertz (THz) region using an S-band linac at the Kyoto University Free Electron Laser (KU-FEL), which is a mid-infrared free-electron laser facility. The CSR beam was emitted from short-pulse electron bunches compressed by a 180° arc, and was transferred to air at a large solid angle of 0.10 rad. The measured CSR energy was 55 μJ per 7 μs macropulse, and KU-FEL was one of the most powerful CSR sources in normal conducting linear accelerator facilities. The CSR spectra were measured using an uncooled pyroelectric detector and a Michelson-type interferometer designed specifically for the KU-FEL electron beam, and had a maximum at a frequency of 0.11 THz. We found that adjusting the energy slit enhanced the CSR energy and shortened the electron beam bunch length in the CSR spectra measurements. Our results demonstrated that the efficient use of the energy slit can help improve the characteristics of CSR. - Highlights: • We have developed intense coherent synchrotron radiation (CSR) at KU-FEL. • The elevation angle of the CSR was correctly measured by a new technique. • The CSR power extracted to the air was 55 μJ per 7 μs macropulse. • It was demonstrated that an energy slit was effective to improve the CSR properties.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-05-23

    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.

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

    International Nuclear Information System (INIS)

    Huang, Z.; Fawley, W.M.

    2001-01-01

    While the long-pulse, coasting beam model is often used in analysis and simulation of self-amplified spontaneous emission (SASE) free-electron lasers (FELs), many current SASE demonstration experiments employ relatively short electron bunches whose pulse length is on the order of the radiation slippage length. In particular, the low-energy undulator test line (LEUTL) FEL at the Advanced Photon Source has recently lased and nominally saturated in both visible and near-ultraviolet wavelength regions with a sub-ps pulse length that is somewhat shorter than the total slippage length in the 22-m undulator system. In this paper we explore several characteristics of the short pulse regime for SASE FELs with the multidimensional, time-dependent simulation code GINGER, concentrating on making a direct comparison with the experimental results from LEUTL. Items of interest include the radiation gain length, pulse energy, saturation position, and spectral bandwidth. We address the importance of short-pulse effects when scaling the LEUTL results to proposed x-ray FELs and also briefly discuss the possible importance of coherent spontaneous emission at startup

  8. Powerful electrostatic FEL: Regime of operation, recovery of the spent electron beam and high voltage generator

    Energy Technology Data Exchange (ETDEWEB)

    Boscolo, I. [Univ. and INFN, Milan (Italy); Gong, J. [Southwest Jiaotong Univ., Chengdu (China)

    1995-02-01

    FEL, driven by a Cockcroft-Walton electrostatic accelerator with the recovery of the spent electron beam, is proposed as powerful radiation source for plasma heating. The low gain and high gain regimes are compared in view of the recovery problem and the high gain regime is shown to be much more favourable. A new design of the onion Cockcroft-Walton is presented.

  9. Ultrafast phenomena at the nanoscale: science opportunities at the SwissFEL X-ray laser

    International Nuclear Information System (INIS)

    Abela, R.; Braun, H.; Ming, P.; Pedrozzi, M.; Quitmann, Ch.; Reiche, S.; Daalen, M. van; Veen, J.F. van der; Mesot, J.; Mesot, J.; Shiroka, T.; Veen, J.F. van der; Mesot, J.

    2009-09-01

    In today's fast-moving society, standing still is effectively synonymous with being left behind. If it is to maintain, beyond the coming 10-15 years, its high international standing as a complex of large research infrastructures, the Paul Scherrer Institute (PSI) must now lay the foundation for a competitive future. Experts worldwide foresee a strongly growing demand within science and technology for photon sources delivering ultra-short, coherent X-ray pulses. Such a source, called a free electron laser (FEL), is nothing less than a gigantic flash camera, allowing us to take a deeper look into matter than with any other machine before. By literally seeing molecules in action, scientists will be able not only to capture chemical and biological processes of direct relevance and benefit to society but also to improve them. It is a dream coming true. For the first time, it will not only be possible to take pictures of molecular structures, we will be able to make movies of their motion. The new X-ray laser project at PSI, known as SwissFEL, will be an important addition to the existing complex of PSI facilities that serve interdisciplinary and international research teams from academia and industry. The SwissFEL is an essential element of Switzerland's strategic focus and will prolong our nation's leading position in scientific research for years to come. It will attract top scientists from Switzerland and abroad, and will strengthen the position of PSI as a world-class research institute. This new high-tech facility will also provide an important incentive for Swiss industry, through which existing highly-qualified jobs will be maintained and new ones created. In this report we present a wide range of important, open questions within science and engineering disciplines that SwissFEL will contribute towards solving. These questions, which form the 'scientific case' for SwissFEL, have been identified through a range of workshops organized over the past few years and by

  10. Upgrading inflatable door seals

    International Nuclear Information System (INIS)

    Sykes, T.M.; Metcalfe, R.; Welch, L.A.; Josefowich, J.M.

    1997-01-01

    Inflatable door seals are used for airlocks in CANDU stations. They have been a significant source of unreliability and maintenance cost. A program is underway to improve their performance and reliability, backed by environmental qualification testing. Only commercial products and suppliers existed in 1993. For historical reasons, these 'existing products' did not use the most durable material then available. In hindsight, neither had they been adapted nor optimized to combat conditions often experienced in the plants-sagging doors, damaged sealing surfaces, and many thousands of openings and closings per year. Initial attempts to involve the two existing suppliers in efforts to upgrade these seals were unsuccessful. Another suitable supplier had therefore to be found, and a 'new,' COG-owned seal developed; this was completed in 1997. This paper summarizes its testing, along with that of the two existing products. Resistance to aging has been improved significantly. Testing has shown that an accident can be safely withstood after 10 years of service or 40,000 openings-closings, whichever comes first. AECL's Fluid Sealing Technology Unit (FSTU) has invested in the special moulds, test fixtures and other necessary tooling and documentation required to begin commercial manufacture of this new quality product. Accordingly, as with FSTU's other nuclear products such as pump seals, the long-term supply of door seals to CANDU plants is now protected from many external uncertainties-e.g., commercial products being discontinued, materials being changed, companies going out of business. Manufacturing to AECL's detailed specifications is being subcontracted to the new supplier. FSTU is performing the quality surveillance, inspection, testing, and customer service activities concomitant with direct responsibility for supply to the plants. (author)

  11. Preliminary results of the Adone storage ring FEL experiment, LELA

    International Nuclear Information System (INIS)

    Barbini, R.; Vignola, G.; Trillo, S.

    1983-01-01

    A short description of the LELA (Free Electron Laser on Adone) experiment is given. Results on the spontaneous radiation angle and energy spectra and preliminary results on optical gain measurements are also discussed

  12. Inverse Compton gamma-ray source for nuclear physics and related applications at the Duke FEL

    International Nuclear Information System (INIS)

    O'Shea, P.G.; Litvinenko, V.N.; Madey, J.M.J.

    1995-01-01

    In recent years the development of intense, short-wavelength FEL light sources has opened opportunities for the development new applications of high-energy Compton-backscattered photons. These applications range from medical imaging with X-ray photons to high-energy physics with γγ colliders. In this paper we discuss the possibilities for nuclear physics studies using polarized Compton backscattered γ-rays from the Duke storage-ring-driven UV-FEL. There are currently a number of projects that produce polarized γ-rays for nuclear physics studies. All of these facilities operate by scattering conventional laser-light against electrons circulating in a storage ring. In our scheme, intra-cavity scattering of the UV-FEL light will produce a γ-flux enhancement of approximately 10 3 over existing sources. The Duke ring can operate at energies up to 1.2 GeV and can produce FEL photons up to 12.5 eV. We plan to generate γ-rays up to 200 MeV in energy with an average flux in excess of 10 7 /s/MeV, using a modest scattering beam of 10-mA average stored current. The γ-ray energy may be tuned by varying the FEL wavelength or by adjusting the stored electron beam energy. Because of the intense flux, we can eliminate the need for photon energy tagging by collimating of the γ-ray beam. We will discuss the characteristics of the device and its research opportunities

  13. Selected issues for the LHC luminosity upgrade

    International Nuclear Information System (INIS)

    Laface, E.

    2008-12-01

    The Large Hadron Collider started its operations on September 10. 2008. In a realistic forecast it is supposed to demonstrate (or confute) the existence of the Higgs boson for the year 2014. After this date the physics of rare events will be explored more in details and an upgrade of the luminosity can make an important difference in the program of experiments at CERN. This thesis proposes several ideas to increase the luminosity of ATLAS and CMS experiments and the acceptance of TOTEM experiment. The main object of study is the Interaction Region, that consists in the set of magnets in charge to provide the final beam focalization for the collisions. The Interaction Region is studied with the methods of beam optics and beam dynamics to design new layouts for the upgrade. These layouts are also explored from the point of view of integrability in the existing experiments developing the analysis of energy deposition and misalignment tolerances. This study was performed with the use of analytical methods for the general considerations and numerical methods for the parameters optimization. (author)

  14. Upgrading the ATLAS Tile Calorimeter Electronics

    CERN Document Server

    Popeneciu, G; The ATLAS collaboration

    2014-01-01

    The Tile Calorimeter (TileCal) is the central hadronic calorimeter of the ATLAS experiment at LHC. Around 2023, after the upgrade of the LHC (High Luminosity LHC, phase 2) the peak luminosity will increase by a factor of 5 compared to the design value (1034 cm-2 s-1), thus requiring an upgrade of the TileCal readout electronics. Except the 9852 photomultipliers (PMTs), most of the on- and off-detector electronics will be replaced, with the aim of digitizing all PMT pulses at 40 MHz at the front-end level and sending them with 10 Gbps optical links to the back-end electronics. Moreover, to increase reliability, redundancy will be introduced at different levels. Three different options are currently being investigated for the front-end electronics and extensive test beam studies are planned to select the best option. One demonstrator prototype module is also planned to be inserted in TileCal in 2014 that will include hybrid electronic components able to probe the new design, but still compatible with the presen...

  15. Project scenarios for bitumen upgrading

    International Nuclear Information System (INIS)

    Koppel, P.E.; Mazurek, W.L.; Harji, A.

    2002-01-01

    The established reserves of Alberta's heavy oil resources are 178 billion barrels, and potential recoverable reserves are 315 billion barrels. The challenge of production includes the logistics of recovery, upgrading and transportation to market. Utilization of the bitumen is not simple because bitumen is too viscous to transport by pipeline. In addition, it is not processable by most existing refineries unless it can be upgraded through dilution. This paper examined different factors regarding the economic viability of various upgrading methods of a wide range of bitumen feedstocks. The study also examined the sensitivity of refinery demand to the prices of these feedstocks, along with the competitiveness among bitumen-based feedstock and conventional crudes. Western Canada, Ontario and the PADD II district in the United States are the 3 major markets for western Canadian bitumen based feedstock, the demand for which depends on refinery configurations and asphalt demand. This paper described the following 4 generic scenarios that describe Alberta bitumen upgrading projects: (1) adjacent to open pit mines, (2) adjacent to steam assisted gravity drainage (SAGD) facilities, (3) remotely located from resource production at an existing refinery, and (4) pipeline bitumen. It was noted that producers should determine the best way to upgrade the bitumen to ensure there is an economic market for the product, but they should also be aware not to over process the bitumen so as not to leave existing refinery facilities under-utilized. 2 refs., 1 tab., 3 figs

  16. Processing options for bitumen upgrading

    International Nuclear Information System (INIS)

    Harji, A.N.; Koppel, P.E.; Mazurek, W.L.; Meysami, P.

    2003-01-01

    It is estimated that 178 billion barrels of oil can be recovered from Alberta's vast heavy oil reserves. The challenge lies in the logistics of recovering, upgrading and transporting the oil to market. The Canadian Energy Research Institute conducted a recent study to determine market potential by 2007 for diluted bitumen and synthetic crude oil produced from upgraded bitumen. The viability for a wide range of bitumen feedstocks was assessed along with the sensitivity of refinery demand to their prices. The 3 major markets for western Canadian bitumen include PADD 2 in the United States, western Canada, and Ontario. Bitumen is too viscous to transport by pipeline and cannot be processed by most of the existing refineries. Therefore, in order to develop a mass market for the product, bitumen must undergo the energy intensive upgrading process at existing refineries. The factors impacting which method of upgrading is most suitable were discussed with particular attention to the impact that Canada's ratification of the Kyoto Protocol may have on Alberta's bitumen resource in terms of costs of complying with greenhouse gas reduction initiatives. The authors emphasized that it is crucial to customize an upgrading project to meet site and market specific factors. 8 refs., 3 tabs., 3 figs

  17. Upgrade of long trace profiler for characterization of high-precision X-ray mirrors at SPring-8

    International Nuclear Information System (INIS)

    Senba, Y.; Kishimoto, H.; Ohashi, H.; Yumoto, H.; Zeschke, T.; Siewert, F.; Goto, S.; Ishikawa, T.

    2010-01-01

    The long trace profiler (LTP) at SPring-8 has been upgraded to improve stability and resolution of slope measurement. The performances of the upgraded LTP at SPring-8 are presented by cross-checking measurements on a flat mirror with data obtained using Nanometer Optical Component Measuring Machine (NOM) at the Helmholtz Zentrum Berlin/BESSY-II.

  18. LHCb: Fast Readout Control for the upgraded readout architecture of the LHCb experiment at CERN

    CERN Multimedia

    Alessio, F

    2013-01-01

    The LHCb experiment at CERN has proposed an upgrade towards a full 40 MHz readout system in order to run between five and ten times its initial design luminosity with an upgraded LHCb detector. As a consequence, the various LHCb sub-systems in the readout architecture will be upgraded to cope with higher sub-detector occupancies, higher rate, and higher readout load. The new architecture, new functionalities, and the first hardware implementation of a new LHCb Readout Control system (commonly referred to as S-TFC) for the upgraded LHCb experiment is here presented. Our attention is focused in describing solutions for the distribution of clock and timing information to control the entire upgraded readout architecture by profiting of a bidirectional optical network and powerful FPGAs, including a real-time mechanism to synchronize the entire system. Solutions and implementations are presented, together with first results on the simulation and the validation of the system.

  19. A Concept for z-Dependent Microbunching Measurements with Coherent X-ray Transition Radiation in a SASE FEL

    CERN Document Server

    Lumpkin, Alex H

    2004-01-01

    Previously, measurements in the visible to VUV regimes of z-dependent microbunching in a self-amplified spontaneous emission (SASE) free-electron laser (FEL) have provided important information about the fundamental mechanisms. In those experiments a thin metal foil was used to block the more intense SASE radiation and to generate coherent optical transition radiation (COTR) as one source in a two-foil interferometer. However, for the proposed Linac Coherent Light Source (LCLS), the intense SASE emission is either too strongly transmitted at 1.5 angstroms or the needed foil thickness for blocking scatters the electron beam too much. Since coherent x-ray transition radiation (CXTR) is emitted in an annulus with opening angle 1/γ = 36 µrad for 14.09-GeV electrons, one could use a thin foil or foil stack to generate the XTR and CXTR and an annular crystal to wavelength sort the radiation. The combined selectivity will favor the CXTR over SASE by about eight orders of magnitude. Time-dependent GINGER si...

  20. Electron beam bunch length characterizations using incoherent and coherent transition radiation on the APS SASE FEL project

    CERN Document Server

    Lumpkin, Alex H; Berg, W J; Lewellen, J W; Sereno, N S; Happek, U

    2000-01-01

    The Advanced Photon Source (APS) injector linac has been reconfigured with a low-emittance RF thermionic gun and a photocathode (PC) RF gun to support self-amplified spontaneous emission (SASE) free-electron laser (FEL) experiments. One of the most critical parameters for optimizing SASE performance (gain length) is the electron beam peak current, which requires a charge measurement and a bunch length measurement capability. We report here initial measurements of the latter using both incoherent optical transition radiation (OTR) and coherent transition radiation (CTR). A visible light Hamamatsu C5680 synchroscan streak camera was used to measure the thermionic RF gun beam's bunch length (sigma approx 2-3 ps) via OTR generated by the beam at 220 MeV and 200 mA macropulse average current. In addition, a CTR monitor (Michelson Interferometer) based on a Golay cell as the far-infrared (FIR) detector has been installed at the 40-MeV station in the beamline. Initial observations of CTR signal strength variation wi...

  1. Physical protection upgrades in Ukraine

    International Nuclear Information System (INIS)

    Djakov, A.

    1998-01-01

    The U.S. DOE is providing nuclear material safeguards assistance in both material control and accountability and in physical protection to several facilities in Ukraine. This paper summarizes the types of physical protection upgrades that have been or are presently being implemented at these facilities. These facilities include the Kiev Institute for Nuclear Research, Kharkov Institute of Physics and Technology, Sevastopol Institute of Nuclear Energy and Industry, and the South Ukraine Nuclear Power Plant. Typical upgrades include: hardening of storage areas; improvements in access control, intrusion detection, and CCTV assessment; central alarm station improvements; and implementation of new voice communication systems. Methods used to implement these upgrades and problems encountered are discussed. Training issues are also discussed

  2. The D0 detector upgrade

    International Nuclear Information System (INIS)

    Bross, A.D.

    1995-02-01

    The Fermilab collider program is undergoing a major upgrade of both the accelerator complex and the two detectors. Operation of the Tevatron at luminosities upwards of ten time that currently provided will occur in early 1999 after the commissioning of the new Fermilab Main Injector. The D0 upgrade program has been established to deliver a detector that will meet the challenges of this environment. A new magnetic tracker consisting of a superconducting solenoid, a silicon vertex detector, a scintillating fiber central tracker, and a central preshower detector will replace the current central tracking and transition radiation chambers. We present the design and performance capabilities of these new systems and describe results from physics simulations that demonstrate the physics reach of the upgraded detector

  3. Environmental upgrading of a landfill

    International Nuclear Information System (INIS)

    Agostinetto, V.; Vendrame, G.

    1999-01-01

    This article refers to an experimental study concerning the vegetative upgrading of a closed-down landfill (once used for industrial waste disposal). The aim was to check the possibility of reconstructing or aiding the natural growth of a vegetation in keeping with the surrounding area, in a tried environment such as that of landfills. The original idea contained in the approved project - which meant to generically upgrade the territory by planting species belonging to the grassy layer, shrubs and trees - has, with time, undergone some changes. On the basis of both the knowledge acquired during management and of a more accurate analysis of the territory, the experiment was preferred to aim at finding out which were the species, both continental and Mediterranean, able to gradually adjust to the surrounding landscape, leaving to natural selection the task to decide which species were more suitable to the upgrading of closed-down landfills, and which planting technique was more effective [it

  4. Hydrogen assisted biological biogas upgrading

    DEFF Research Database (Denmark)

    Bassani, Ilaria

    Wind and biomass are promoted worldwide as sustainable forms of energy. Anaerobic digestion of biomass produces biogas with ∼50−70% CH4 and 30−50% CO2. However, biogas with >90% CH4 content has higher heating value, can be injected into the natural gas grid or used as alternative to natural gas...... as vehicle fuel. Methods currently available for biogas upgrading mainly consists of physicochemical CO2 removal, requiring the use of chemical substances and energy input and, thus, increasing process costs. This PhD project proposes an alternative to existing biogas upgrading technologies, where H2......, produced by water electrolysis, using excess of electricity from wind mills, is coupled with the CO2 contained in the biogas to convert them to CH4. This process is defined as biological biogas upgrading and is carried out by hydrogenotrophic methanogenic archaea that couples CO2 with H2 to produce...

  5. Status of TMX upgrade diagnostics construction

    International Nuclear Information System (INIS)

    Hornady, R.S.; Davis, J.C.; Simonen, T.C.

    1981-01-01

    This report describes the status of the initial TMX Upgrade diagnostics and the state of development of additional diagnostics being prepared for later TMX Upgrade experiments. The initial diagnostic instrument set has been described in the TMX Upgrade Proposal. This set is required to get TMX Upgrade operational and to evaluate its initial performance. Additional diagnostic instruments are needed to then carry out the more detailed experiments outlined by the TMX Upgrade program milestones. The relation of these new measurements to the physics program is described in The TMX Upgrade Program Plan

  6. Enhancement of Permeation in Transdermal Drug Delivery System by 6μm Wavelength Area Using an MIR-FEL

    Science.gov (United States)

    Uchizono, T.; Ishii, K.; Iwao, Y.; Itou, Y.; Maruo, H.; Hori, M.; Awazu, K.

    2005-03-01

    Ablation of the stratum corneum (SC) by pulsed-laser irradiation is one method of enhancing transdermal drug delivery (TD). For non-invasive laser TD treatment, we have tried to enhance TD without ablation of the SC using an MIR-FEL (6-μm wavelength) (FEL : free electron laser). Lidocaine was used as the drug in this study. The enhancement of TD was measured by HPLC. It was found that the lidocaine TD of the sample irradiated by MIR-FEL was enhanced 10 fold faster than the non-irradiated sample with a flux at 0.5 μg/cm2/h, measured by HPLC. We have demonstrated the effectiveness of TD enhancement by an MIR-FEL (6-μm wavelength) irradiation.

  7. A high-average power tapered FEL amplifier at submillimeter frequencies using sheet electron beams and short-period wigglers

    International Nuclear Information System (INIS)

    Bidwell, S.W.; Radack, D.J.; Antonsen, T.M. Jr.; Booske, J.H.; Carmel, Y.; Destler, W.W.; Granatstein, V.L.; Levush, B.; Latham, P.E.; Zhang, Z.X.

    1990-01-01

    A high-average-power FEL amplifier operating at submillimeter frequencies is under development at the University of Maryland. Program goals are to produce a CW, ∼1 MW, FEL amplifier source at frequencies between 280 GHz and 560 GHz. To this end, a high-gain, high-efficiency, tapered FEL amplifier using a sheet electron beam and a short-period (superconducting) wiggler has been chosen. Development of this amplifier is progressing in three stages: (1) beam propagation through a long length (∼1 m) of short period (λ ω = 1 cm) wiggler, (2) demonstration of a proof-of-principle amplifier experiment at 98 GHz, and (3) designs of a superconducting tapered FEL amplifier meeting the ultimate design goal specifications. 17 refs., 1 fig., 1 tab

  8. Upgrade of reactor operation technology

    International Nuclear Information System (INIS)

    Itoh, Hideaki; Suzuki, Toshiaki; O-kawa, Toshikatsu

    2003-01-01

    To improve operational reliability and availability, the operation technology for a fast reactor was developed in the ''JOYO''. This report describes the upgrading of the simulator, plant operation management tools and fuel handling system for the MK-III core operation. The simulator was modified to the MK-III version to verify operation manuals, and to train operators in MK-III operation. The plant operation management tool was replaced on the operation experience to increase the reliability and efficiency of plant management works relating to plant operation and maintenance. To shorten the refueling period, the fuel handling system was upgraded to full automatic remote control. (author)

  9. Upgrading the BEPC control system

    International Nuclear Information System (INIS)

    Yang Liping; Wang Lizheng; Liu Shiyao

    1992-01-01

    The BEPC control system has been put into operation and operated normally since the end of 1987. Three years's experience shows this system can satisfy basically the operation requirements, also exhibits some disadvantages araised from the original centralized system architecture based on the VAX-VCC-CAMAC, such as slow response, bottle neck of VCC, less CPU power for control etc.. This paper describes the method and procedure for upgrading the BEPC control system which will be based on DEC net and DEC-WS, and thus intend to upgrade the control system architecture from the centralized to the distributed and improve the integral system performance. (author)

  10. Argonne's atlas control system upgrade

    International Nuclear Information System (INIS)

    Munson, F.; Quock, D.; Chapin, B.; Figueroa, J.

    1999-01-01

    The ATLAS facility (Argonne Tandem-Linac Accelerator System) is located at the Argonne National Laboratory. The facility is a tool used in nuclear and atomic physics research, which focuses primarily on heavy-ion physics. The accelerator as well as its control system are evolutionary in nature, and consequently, continue to advance. In 1998 the most recent project to upgrade the ATLAS control system was completed. This paper briefly reviews the upgrade, and summarizes the configuration and features of the resulting control system

  11. Reflections on a digital upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Tadjalli, M.

    2013-07-01

    Upon receiving US NRC's approval in 2010, the first RPS/ESPS digital upgrade using TELEPERM® XS technology was successfully installed in Spring of 2011 at the first Unit of a three-unit station, followed by the 2nd Unit installation in spring of 2012. Both Units' systems have been operating flawlessly since installation. After about two years of operation, a reflection on digital upgrades and lessons learned, from a vendor perspective, provides valuable insight for the commercial nuclear power industry.

  12. LHCb DAQ network upgrade tests

    CERN Document Server

    Pisani, Flavio

    2013-01-01

    My project concerned the evaluation of new technologies for the DAQ network upgrade of LHCb. The first part consisted in developing and Open Flow-based Clos network. This new technology is very interesting and powerful but, as shown by the results, it still needs further improvements. The second part consisted in testing and benchmarking 40GbE network equipment: Mellanox MT27500, Chelsio T580 and Huawei Cloud Engine 12804. An event-building simulation is currently been performed in order to check the feasibility of the DAQ network upgrade in LS2. The first results are promising.

  13. LLL hydrodiagnostics upgrade program

    International Nuclear Information System (INIS)

    Carpluk, G.T.; Innes, T.G.; Trost, S.R.

    1978-01-01

    The continued success of the nuclear weapon design and test programs is a direct result of the effective hydrodynamic programs developed at Livermore. Hydrodynamic studies provide the weapon designer with experimental verification and analysis of weapon designs through the use of explosively driven, nonfissile materials. Hydrodiagnostic techniques include (1) flash radiography; (2) high-speed photography; (3) electrical-pin diagnostics; and (4) interferometry. The focus of all hydrodynamic testing at LLL is the Site 300 Explosive Test Area located 18 miles east of Livermore. This remote, 10-mi 2 facility consists of: (1) areas for machining and assembling explosives; (2) environmental test facilities; (3) administrative and support facilities; and (4) five underground, reinforced-concrete bunkers equipped with high-speed cameras, electrical data-acquisition systems, and electron accelerators for flash radiography. The report summarizes the improvements made in radiography, optics, electronics, and interferometry, and indicates the projects that remain to be completed

  14. Study with one global crab cavity at IR4 for LHC Upgrade

    CERN Document Server

    Barranco, J; Morita, A; Ralph Assmann, R; Sun, Y; Tomás, R; Weiler, T; Zimmermann, F; CERN. Geneva. BE Department

    2009-01-01

    In this note, we discuss the possible installation and impact on the beam of a single global crab cavity (CC) for both nominal LHC optics and one upgrade LHC optics (Lowbetamax). We also summarize the results on dynamic aperture tracking, luminosity, expected closed orbits, preliminary studies on collimation cleaning efficiency, and the emittance growth due to crab cavity ramping and other sources.

  15. Plasma diagnostics for the DIII-D divertor upgrade (abstract)

    International Nuclear Information System (INIS)

    Hill, D.N.; Futch, A.; Buchenauer, D.; Doerner, R.; Lehmer, R.; Schmitz, L.; Klepper, C.C.; Menon, M.; Leikind, B.; Lippmann, S.; Mahdavi, M.A.; Schaffer, M.; Smith, J.; Salmonson, J.; Watkins, J.

    1990-01-01

    The DIII-D tokamak is being upgraded to allow for divertor biasing, baffling, and pumping experiments. This paper gives an overview of the new diagnostics added to DIII-D as part of this advanced divertor program. They include tile current monitors, fast reciprocating Langmuir probes, a fixed probe array in the divertor, fast neutral pressure gauges, and H α measurements with TV cameras and fiber optics coupled to a high-resolution spectrometer

  16. Investigations on the electron bunch distribution in the longitudinal phase space at a laser driven RF electron source for the European X-FEL

    Energy Technology Data Exchange (ETDEWEB)

    Roensch, Juliane

    2010-01-15

    The Photoinjector Test facility at DESY, Zeuthen site, (PITZ) is aiming for the optimization of electron guns for SAS-FELs. For this it is necessary to investigate the characteristics of the six dimensional phase space of the bunch produced by a photoinjector. This thesis is focused on the analysis of the longitudinal properties of the electron bunch distribution, this means the temporal current distribution and the momentum distribution as well as the correlation of both properties. The complete distribution of the electron bunch in longitudinal phase space of a photoinjector was measured directly for the first time at a beam momentum of about 5 MeV/c, using an existing apparatus. This system had been designed for an accelerating gradient of 40 MV/m. Its subcomponents were analysed to understand sources of uncertainties of the measurement system. The usage of higher accelerating gradients in the gun (60 MV/m, resulting in a beam momentum of about 6.8 MeV/c) demands major modifications of the existing measurement system for the longitudinal phase space distribution. An upgrade of the facility by an additional accelerating cavity required the design of further longitudinal diagnostics systems for the analysis at higher momenta (up to 40 MeV/c). Measurements of the longitudinal beam properties to determine the influence of different operation parameters, like RF launch phase, charge, accelerating field gradient and laser distribution were performed and compared to simulations. (orig.)

  17. Investigations on the electron bunch distribution in the longitudinal phase space at a laser driven RF electron source for the European X-FEL

    International Nuclear Information System (INIS)

    Roensch, Juliane

    2010-01-01

    The Photoinjector Test facility at DESY, Zeuthen site, (PITZ) is aiming for the optimization of electron guns for SAS-FELs. For this it is necessary to investigate the characteristics of the six dimensional phase space of the bunch produced by a photoinjector. This thesis is focused on the analysis of the longitudinal properties of the electron bunch distribution, this means the temporal current distribution and the momentum distribution as well as the correlation of both properties. The complete distribution of the electron bunch in longitudinal phase space of a photoinjector was measured directly for the first time at a beam momentum of about 5 MeV/c, using an existing apparatus. This system had been designed for an accelerating gradient of 40 MV/m. Its subcomponents were analysed to understand sources of uncertainties of the measurement system. The usage of higher accelerating gradients in the gun (60 MV/m, resulting in a beam momentum of about 6.8 MeV/c) demands major modifications of the existing measurement system for the longitudinal phase space distribution. An upgrade of the facility by an additional accelerating cavity required the design of further longitudinal diagnostics systems for the analysis at higher momenta (up to 40 MeV/c). Measurements of the longitudinal beam properties to determine the influence of different operation parameters, like RF launch phase, charge, accelerating field gradient and laser distribution were performed and compared to simulations. (orig.)

  18. A hybrid type undulator for far-infrared FELs at FELI

    Energy Technology Data Exchange (ETDEWEB)

    Zako, A.; Miyauchi, Y.; Koga, A. [Free Electron Laser Research Institute, Inc., Osaka (Japan)] [and others

    1995-12-31

    Two FEL facilities of the FELI are now operating in the wavelength range of 1-20 {mu}m. A 3.2-m hybrid type undulator ({lambda}{sub u}=80mm, N=40) has been designed for far-infrared FELs and will be installed in December. It can cover the wavelength of 20-60 {mu}m by changing K-value from 1 to 2.7 for a 28.0-MeV electron beam. It is composed of ferrite magnetic poles and Sm-Co permanent magnets. Commonly wound coils induce alternating magnetic field in ferrite poles. Combination of the induced field and the permanent magnet field can controls the magnetic field between the undulator gap.

  19. Femtosecond X-ray Pulses from a Spatially Chirped Electron Bunch in a SASE FEL

    Energy Technology Data Exchange (ETDEWEB)

    Emma, P.

    2003-01-14

    We propose a simple method to produce short x-ray pulses using a spatially chirped electron bunch in a SASE FEL. The spatial chirp is generated using an rf deflector which produces a transverse offset (in y and/or y') correlated with the longitudinal bunch position. Since the FEL gain is very sensitive to an initial offset in the transverse phase space at the entrance of the undulator, only a small portion of the electron bunch with relatively small transverse offset will interact significantly with the radiation, resulting in an x-ray pulse length much shorter than the electron bunch length. The x-ray pulse is also naturally phase locked to the rf deflector and so allows high precision timing synchronization. We discuss the generation and transport of such a spatially chirped electron beam and show that tens of femtosecond long pulse can be generated for the linac coherent light source (LCLS).

  20. EUV stimulated emission from MgO pumped by FEL pulses

    Directory of Open Access Journals (Sweden)

    Philippe Jonnard

    2017-09-01

    Full Text Available Stimulated emission is a fundamental process in nature that deserves to be investigated and understood in the extreme ultra-violet (EUV and x-ray regimes. Today, this is definitely possible through high energy density free electron laser (FEL beams. In this context, we give evidence for soft-x-ray stimulated emission from a magnesium oxide solid target pumped by EUV FEL pulses formed in the regime of travelling-wave amplified spontaneous emission in backward geometry. Our results combine two effects separately reported in previous works: emission in a privileged direction and existence of a material-dependent threshold for the stimulated emission. We develop a novel theoretical framework, based on coupled rate and transport equations taking into account the solid-density plasma state of the target. Our model accounts for both observed mechanisms that are the privileged direction for the stimulated emission of the Mg L2,3 characteristic emission and the pumping threshold.

  1. First operation of a powerful FEL with two-dimensional distributed feedback

    CERN Document Server

    Agarin, N V; Bobylev, V B; Ginzburg, N S; Ivanenko, V G; Kalinin, P V; Kuznetsov, S A; Peskov, N Yu; Sergeev, A S; Sinitsky, S L; Stepanov, V D

    2000-01-01

    A W-band (75 GHz) FEL of planar geometry driven by a sheet electron beam was realised using the pulse accelerator ELMI (0.8 MeV/3 kA/5 mu s). To provide the spatial coherence of radiation from different parts of the electron beam with a cross-section of 0.4x12 cm two-dimensional distributed feedback systems have been employed using a 2-D Bragg resonator of planar geometry. The resonator consisted of two 2-D Bragg reflectors separated by a regular waveguide section. The total energy in the microwave pulse of microsecond duration was 100 J corresponding to a power of approx 100 MW. The main component of the FEL radiation spectrum was at 75 GHz that corresponded to the zone of effective Bragg reflection found from 'cold' microwave testing of the resonator. The experimental data compared well with the results of theoretical analysis.

  2. An Experimental Study of an FEL Oscillator with a Linear Taper

    International Nuclear Information System (INIS)

    Benson, S.; Gubeli, J.; Neil, G.R.

    2001-01-01

    Motivated by the work of Saldin, Schneidmiller and Yurkov, we have measured the detuning curve widths, spectral characteristics, efficiency, and energy spread as a function of the taper for low and high Q resonators in the IR Demo FEL at Jefferson Lab. Both positive and negative tapers were used. Gain and frequency agreed reasonably well with the predictions of a single mode theory. The efficiency agreed reasonably well for a negative taper with a high Q resonator but disagreed for lower Q values due to the large slippage parameter and the non-ideal resonator Q. We saw better efficiency for a negative taper than for the same positive taper. The energy spread induced in the beam, normalized to the efficiency is larger for the positive taper than for the corresponding negative taper. This indicates that a negative taper is preferred over a positive taper in an energy recovery FEL

  3. Design of RF chopper system for improving beam quality in FEL injector with thermionic gun

    International Nuclear Information System (INIS)

    Chen, Q.; Qin, B.; Tan, P.; Hu, T.; Pei, Y.; Zhang, F.

    2014-01-01

    For a linac-based Free Electron Laser (FEL), good beam quality largely contributes to the success of the final radiation. An imperfection confronted with the HUST THz-FEL facility is the long beam tail that emerges in the electron gun and exists through the whole beam line. This paper proposes to deploy a chopper system after the electron gun to truncate the beam tails before they enter into the linac. Physical dimensions of the chopper cavity are discussed in detail and we have developed and derived new analytical expressions applying to all frequencies for the optimal design. Also, technical issues of the cavity are considered. Beam dynamic simulation is performed to examine the truncation effect and the results show that more than 78% of the beam tail can be removed effectively, while preserving the emittance and energy spread in acceptable level

  4. BEAM OPTIMIZATION STUDY FOR AN X-RAY FEL OSCILLATOR AT THE LCLS-II

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Weilun; Huang, S.; Liu, K.X.; Huang, Z; Ding, Y.; Maxwell, T.J.; Kim, K.-J.

    2016-06-01

    The 4 GeV LCLS-II superconducting linac with high repetition beam rate enables the possibility to drive an X-Ray FEL oscillator at harmonic frequencies *. Compared to the regular LCLS-II machine setup, the oscillator mode requires a much longer bunch length with a relatively lower current. Also a flat longitudinal phase space distribution is critical to maintain the FEL gain since the X-ray cavity has extremely narrow bandwidth. In this paper, we study the longitudinal phase space optimization including shaping the initial beam from the injector and optimizing the bunch compressor and dechirper parameters. We obtain a bunch with a flat energy chirp over 400 fs in the core part with current above 100 A. The optimization was based on LiTrack and Elegant simulations using LCLS-II beam parameters.

  5. Preliminary Design of a Synchronized Narrow Bandwidth FEL for Taiwan Light Source

    CERN Document Server

    Keung Lau Wai; Ching Fan, Tai; Zone Hsiao Feng; Tung Hsu Kuo; Hwang, Ching Shiang; Cheng Kuo Chin; Huei Luo Guo; Jen Wang Duan; Ping Wang Jau; Huey Wang Min

    2004-01-01

    Design study of a narrow line-width, high power IR-FEL facility has been carried out at NSRRC. This machine is designed to synchronize with the U9 undulator radiation of Taiwan Light Source and therefore provide new opportunity for chemical dynamics and condensed matter research. It has been proposed to use a super-conducting linac to provide a 60 MeV high quality electron beam to drive a 2.5-10 microns FEL oscillator with U5 undulator. Operating this linac in energy recovery mode will also be considered as an option to improve overall system effeciency and reduce heat loss and radiation dosage at the beam dump. Performance requirements and outcomes from this preliminary design study will be reported.

  6. Nearly copropagating sheared laser pulse FEL undulator for soft x-rays

    International Nuclear Information System (INIS)

    Lawler, J E; Yavuz, D; Bisognano, J; Bosch, R A; Chiang, T C; Green, M A; Jacobs, K; Miller, T; Wehlitz, R; York, R C

    2013-01-01

    A conceptual design for a soft x-ray free-electron laser (FEL) using a short-pulsed, high energy near infrared laser undulator and a low-emittance modest-energy (∼170 MeV) electron beam is described. This low-cost design uses the laser undulator beam in a nearly copropagating fashion with respect to the electron beam, instead of the traditional ‘head-on’ fashion. The nearly copropagating geometry reduces the Doppler shift of scattered radiation to yield soft, rather than hard x-rays. To increase the FEL gain a sheared laser pulse from a Ti : sapphire or other broadband laser is used to extend the otherwise short interaction time of the nearly copropagating laser undulator beam with a relativistic electron beam. (paper)

  7. Old PCs: Upgrade or Abandon?

    Science.gov (United States)

    Perez, Ernest

    1997-01-01

    Examines the practical realities of upgrading Intel personal computers in libraries, considering budgets and technical personnel availability. Highlights include adding RAM; putting in faster processor chips, including clock multipliers; new hard disks; CD-ROM speed; motherboards and interface cards; cost limits and economic factors; and…

  8. Overview of ASDEX Upgrade results

    NARCIS (Netherlands)

    Stroth, U.; Adamek, J.; Aho-Mantila, L.; Akaslompolo, S.; Amdor, C.; Angioni, C.; Balden, M.; Bardin, S.; L. Barrera Orte,; Behler, K.; Belonohy, E.; Bergmann, A.; Bernert, M.; Bilato, R.; Birkenmeier, G.; Bobkov, V.; Boom, J.; Bottereau, C.; Bottino, A.; Braun, F.; Brezinsek, S.; Brochard, T.; M. Brüdgam,; Buhler, A.; Burckhart, A.; Casson, F. J.; Chankin, A.; Chapman, I.; Clairet, F.; Classen, I.G.J.; Coenen, J. W.; Conway, G. D.; Coster, D. P.; Curran, D.; da Silva, F.; P. de Marné,; D' Inca, R.; Douai, D.; Drube, R.; Dunne, M.; Dux, R.; Eich, T.; Eixenberger, H.; Endstrasser, N.; Engelhardt, K.; Esposito, B.; Fable, E.; Fischer, R.; H. Fünfgelder,; Fuchs, J. C.; K. Gál,; M. García Muñoz,; Geiger, B.; Giannone, L.; T. Görler,; da Graca, S.; Greuner, H.; Gruber, O.; Gude, A.; Guimarais, L.; S. Günter,; Haas, G.; Hakola, A. H.; Hangan, D.; Happel, T.; T. Härtl,; Hauff, T.; Heinemann, B.; Herrmann, A.; Hobirk, J.; H. Höhnle,; M. Hölzl,; Hopf, C.; Houben, A.; Igochine, V.; Ionita, C.; Janzer, A.; Jenko, F.; Kantor, M.; C.-P. Käsemann,; Kallenbach, A.; S. Kálvin,; Kantor, M.; Kappatou, A.; Kardaun, O.; Kasparek, W.; Kaufmann, M.; Kirk, A.; H.-J. Klingshirn,; Kocan, M.; Kocsis, G.; Konz, C.; Koslowski, R.; Krieger, K.; Kubic, M.; Kurki-Suonio, T.; Kurzan, B.; Lackner, K.; Lang, P. T.; Lauber, P.; Laux, M.; Lazaros, A.; Leipold, F.; Leuterer, F.; Lindig, S.; Lisgo, S.; Lohs, A.; Lunt, T.; Maier, H.; Makkonen, T.; Mank, K.; M.-E. Manso,; Maraschek, M.; Mayer, M.; McCarthy, P. J.; McDermott, R.; Mehlmann, F.; Meister, H.; Menchero, L.; Meo, F.; Merkel, P.; Merkel, R.; Mertens, V.; Merz, F.; Mlynek, A.; Monaco, F.; Müller, S.; H.W. Müller,; M. Münich,; Neu, G.; Neu, R.; Neuwirth, D.; Nocente, M.; Nold, B.; Noterdaeme, J. M.; Pautasso, G.; Pereverzev, G.; B. Plöckl,; Podoba, Y.; Pompon, F.; Poli, E.; Polozhiy, K.; Potzel, S.; Puschel, M. J.; Putterich, T.; Rathgeber, S. K.; Raupp, G.; Reich, M.; Reimold, F.; Ribeiro, T.; Riedl, R.; Rohde, V.; van Rooij, G. J.; Roth, J.; Rott, M.; Ryter, F.; Salewski, M.; Santos, J.; Sauter, P.; Scarabosio, A.; Schall, G.; Schmid, K.; Schneider, P. A.; Schneider, W.; Schrittwieser, R.; Schubert, M.; Schweinzer, J.; Scott, B.; Sempf, M.; Sertoli, M.; Siccinio, M.; Sieglin, B.; Sigalov, A.; Silva, A.; Sommer, F.; A. Stäbler,; Stober, J.; Streibl, B.; Strumberger, E.; Sugiyama, K.; Suttrop, W.; Tala, T.; Tardini, G.; Teschke, M.; Tichmann, C.; Told, D.; Treutterer, W.; Tsalas, M.; VanZeeland, M. A.; Varela, P.; Veres, G.; Vicente, J.; Vianello, N.; Vierle, T.; Viezzer, E.; Viola, B.; Vorpahl, C.; Wachowski, M.; Wagner, D.; Wauters, T.; Weller, A.; Wenninger, R.; Wieland, B.; Willensdorfer, M.; Wischmeier, M.; Wolfrum, E.; E. Würsching,; Yu, Q.; Zammuto, I.; Zasche, D.; Zehetbauer, T.; Zhang, Y.; Zilker, M.; Zohm, H.

    2013-01-01

    The medium size divertor tokamak ASDEX Upgrade (major and minor radii 1.65 m and 0.5 m, respectively, magnetic-field strength 2.5 T) possesses flexible shaping and versatile heating and current drive systems. Recently the technical capabilities were extended by increasing the electron cyclotron

  9. Overview of ASDEX Upgrade results

    DEFF Research Database (Denmark)

    Kallenbach, A.; Adamek, J.; Aho-Mantila, L.

    2011-01-01

    The ASDEX Upgrade programme is directed towards physics input to critical elements of the ITER design and the preparation of ITER operation, as well as addressing physics issues for a future DEMO design. After the finalization of the tungsten coating of the plasma facing components, the re-availa...

  10. Overview of ASDEX Upgrade results

    DEFF Research Database (Denmark)

    Stroth, U.; Adamek, J.; Aho-Mantila, L.

    2013-01-01

    The medium size divertor tokamak ASDEX Upgrade (major and minor radii 1.65 m and 0.5 m, respectively, magnetic-field strength 2.5 T) possesses flexible shaping and versatile heating and current drive systems. Recently the technical capabilities were extended by increasing the electron cyclotron r...

  11. Overview of ASDEX Upgrade results

    NARCIS (Netherlands)

    Kallenbach, A.; Adamek, J.; Aho-Mantila, L.; Akaslompolo, S.; Angioni, C.; Atanasiu, C. V.; Balden, M.; Behler, K.; Belonohy, E.; Bergmann, A.; Bernert, M.; Bilato, R.; Bobkov, V.; Boom, J.; Bottino, A.; Braun, F.; Brudgam, M.; Buhler, A.; Burckhart, A.; Chankin, A.; Classen, I.G.J.; Conway, G. D.; Coster, D. P.; de Marne, P.; D' Inca, R.; Drube, R.; Dux, R.; Eich, T.; Endstrasser, N.; Engelhardt, K.; Esposito, B.; Fable, E.; Fahrbach, H. U.; Fattorini, L.; Fischer, R.; Flaws, A.; Funfgelder, H.; Fuchs, J. C.; Gal, K.; Munoz, M. G.; Geiger, B.; Adamov, M. G.; Giannone, L.; Giroud, C.; Gorler, T.; da Graca, S.; Greuner, H.; Gruber, O.; Gude, A.; Gunter, S.; Haas, G.; Hakola, A. H.; Hangan, D.; Happel, T.; Hauff, T.; Heinemann, B.; Herrmann, A.; Hicks, N.; Hobirk, J.; Hohnle, H.; Holzl, M.; Hopf, C.; Horton, L.; Huart, M.; Igochine, V.; Ionita, C.; Janzer, A.; Jenko, F.; Kasemann, C. P.; Kalvin, S.; Kardaun, O.; Kaufmann, M.; Kirk, A.; Klingshirn, H. J.; Kocan, M.; Kocsis, G.; Kollotzek, H.; Konz, C.; Koslowski, R.; Krieger, K.; Kurki-Suonio, T.; Kurzan, B.; Lackner, K.; Lang, P. T.; Lauber, P.; Laux, M.; Leipold, F.; Leuterer, F.; Lohs, A.; N C Luhmann Jr.,; Lunt, T.; Lyssoivan, A.; Maier, H.; Maggi, C.; Mank, K.; Manso, M. E.; Maraschek, M.; Martin, P.; Mayer, M.; McCarthy, P. J.; McDermott, R.; Meister, H.; Menchero, L.; Meo, F.; Merkel, P.; Merkel, R.; Mertens, V.; Merz, F.; Mlynek, A.; Monaco, F.; Muller, H. W.; Munich, M.; Murmann, H.; Neu, G.; Neu, R.; Nold, B.; Noterdaeme, J. M.; Park, H. K.; Pautasso, G.; Pereverzev, G.; Podoba, Y.; Pompon, F.; Poli, E.; Polochiy, K.; Potzel, S.; Prechtl, M.; Puschel, M. J.; Putterich, T.; Rathgeber, S. K.; Raupp, G.; Reich, M.; Reiter, B.; Ribeiro, T.; Riedl, R.; Rohde, V.; Roth, J.; Rott, M.; Ryter, F.; Sandmann, W.; Santos, J.; Sassenberg, K.; Sauter, P.; Scarabosio, A.; Schall, G.; Schmid, K.; Schneider, P. A.; Schneider, W.; Schramm, G.; Schrittwieser, R.; Schweinzer, J.; Scott, B.; Sempf, M.; Serra, F.; Sertoli, M.; Siccinio, M.; Sigalov, A.; Silva, A.; Sips, A.C.C.; Sommer, F.; Stabler, A.; Stober, J.; Streibl, B.; Strumberger, E.; Sugiyama, K.; Suttrop, W.; Szepesi, T.; Tardini, G.; Tichmann, C.; Told, D.; Treutterer, W.; Urso, L.; Varela, P.; Vincente, J.; Vianello, N.; Vierle, T.; Viezzer, E.; Vorpahl, C.; Wagner, D.; Weller, A.; Wenninger, R.; Wieland, B.; Wigger, C.; Willensdorfer, M.; Wischmeier, M.; Wolfrum, E.; Wursching, E.; Yadikin, D.; Yu, Q.; Zammuto, I.; Zasche, D.; Zehetbauer, T.; Zhang, Y.; Zilker, M.; Zohm, H.

    2011-01-01

    The ASDEX Upgrade programme is directed towards physics input to critical elements of the ITER design and the preparation of ITER operation, as well as addressing physics issues for a future DEMO design. After the finalization of the tungsten coating of the plasma facing components, the

  12. Overview of ASDEX Upgrade results

    DEFF Research Database (Denmark)

    Zohm, H.; Adamek, J.; Angioni, C.

    2009-01-01

    ASDEX Upgrade was operated with a fully W-covered wall in 2007 and 2008. Stationary H-modes at the ITER target values and improved H-modes with H up to 1.2 were run without any boronization. The boundary conditions set by the full W wall (high enough ELM frequency, high enough central heating and...

  13. Upgrading of the Budapest reactor

    International Nuclear Information System (INIS)

    Rosta, L.

    1986-10-01

    The increasing importance of neutron sources, high demand for irradiation and experimental facilities as well as improved safety requirements in the 'eighties, necessitate not only a technical modernization of the Reactor but an overall upgrade including instrumentation. Such a reconstruction was decided by the Hungarian governement in 1983

  14. Upgrading of the West Area

    CERN Multimedia

    1983-01-01

    The rejigged main hall (EHW1) in the West Area: on background, below the crane, is the brown yoke of the Omega magnet which had been resited. The upgrading was completed by the time in July when 400 GeV protons arrived. See Annual Report 1983 p. 107.

  15. LHC challenges and upgrade options

    Energy Technology Data Exchange (ETDEWEB)

    Bruning, O [CERN AB/ABP, Y03600, 1211 Geneva 23 (Switzerland)], E-mail: Oliver.Bruning@cern.ch

    2008-05-15

    The presentation summarizes the key parameters of the LHC collider. Following a discussion of the main challenges for reaching the nominal machine performance the presentation identifies options for increasing the operation tolerances and the potential performance reach of the LHC by means of future hardware upgrades of the LHC and its injector complex.

  16. LHC challenges and upgrade options

    International Nuclear Information System (INIS)

    Bruning, O

    2008-01-01

    The presentation summarizes the key parameters of the LHC collider. Following a discussion of the main challenges for reaching the nominal machine performance the presentation identifies options for increasing the operation tolerances and the potential performance reach of the LHC by means of future hardware upgrades of the LHC and its injector complex

  17. Five-Megajoule Homopolar Upgrade

    Science.gov (United States)

    1981-06-01

    near the bearing lands to monitor temperature rise during motoring. AISI 4140 steel sleeves were shrunk onto the beryllium copper shaft of the new...MJ HPG in this upgrade. Rotor and Shaft A 0.75-m diameter, 0.28-m thick AISI 4340 air- craft quality steel rotor is shrunk on to a 0. 14-m diameter

  18. Overview of ASDEX Upgrade results

    DEFF Research Database (Denmark)

    Kallenbach, A.; Aguiam, D.; Aho-Mantila, L.

    2017-01-01

    The ASDEX Upgrade (AUG) programme is directed towards physics input to critical elements of the ITER design and the preparation of ITER operation, as well as addressing physics issues for a future DEMO design. Since 2015, AUG is equipped with a new pair of 3-strap ICRF antennas, which were design...

  19. Status of RF system for the JAERI energy-recovery linac FEL

    International Nuclear Information System (INIS)

    Sawamura, Masaru; Nagai, Ryoji

    2006-01-01

    The two types of the RF sources are used for the JAERI ERL-FEL. One is an all-solid state amplifier and the other is an inductive output tube (IOT). There are advantages of little failure and wide bandwidth for the all-solid state amplifier, low cost and high efficiency for IOT. The property of low cost with the IOT is suitable for a large machine like an energy recovery linac (ERL)

  20. Dynamical aspects on FEL interaction in single passage and storage ring devices

    Energy Technology Data Exchange (ETDEWEB)

    Dattoli, G.; Renieri, A. [ENEA, Frascati (Italy)

    1995-12-31

    The dynamical behaviour of the free-electron lasers is investigated using appropriate scaling relations valid for devices operating in the low and high gain regimes, including saturation. The analysis is applied to both single passage and storage ring configurations. In the latter case the interplay between the interaction of the electron bean with the laser field and with the accelerator environment is investigated. In particular we discuss the effect of FEL interaction on the microwave instability.

  1. Luminescence from ZnSe excited by picosecond mid-infrared FEL pulses

    International Nuclear Information System (INIS)

    Mitsuyu, T.; Suzuki, T.; Tomimasu, T.

    1998-01-01

    We have observed blue band-edge emission from a ZnSe crystal under irradiation of mid-infrared picosecond free electron laser (FEL) pulses. The emission characteristics including spectrum, excitation power dependence, excitation wavelength dependence, and decay time have been investigated. The experimental results have indicated that it is difficult to understand the excitation process by multiphoton excitation, thermal excitation, or excitation through mid-gap levels. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

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

    International Nuclear Information System (INIS)

    Venturini, M.; Corlett, J.; Doolittle, L.; Filippetto, D.; Papadopoulos, C.; Penn, G.; Prosnitz, D.; Qiang, J.; Reinsch, M.; Ryne, R.; Sannibale, F.; Staples, J.; Wells, R.; Wurtele, J.; Zolotorev, M.; Zholents, A.

    2011-01-01

    We report on on-going studies of a superconducting CW linac driver intended to support a high repetition rate FEL operating in the soft x-rays spectrum. We present a pointdesign for a 1.8 GeV machine tuned for 300 pC bunches and delivering low-emittance, low-energy spread beams as needed for the SASE and seeded beamlines.

  3. Selected applications of planar permanent magnet multipoles in FEL insertion device design

    International Nuclear Information System (INIS)

    Tatchyn, R.

    1993-08-01

    In recent work, a new class of magnetic multipoles based on planar configurations of permanent magnet (PM) material has been developed. These structures, in particular the quadrupole and sextupole, feature fully open horizontal apertures, and are comparable in effectiveness to conventional iron multipole structures. In this paper results of recent measurements of planar PM quadrupoles and sextupoles are reported and selected applications to FEL insertion device design are considered

  4. Upgrade of the Los Alamos Plutonium Facility control system

    International Nuclear Information System (INIS)

    Pope, N.G.; Turner, W.J.; Brown, R.E.; Bibeau, R.A.; Davis, R.R.; Hogan, K.

    1996-01-01

    After 20 yrs service, the Los Alamos Plutonium Facility is undergoing an upgrade to its aging Facility Control System. The new system design includes a network of redundantly-paired programmable logic controllers that will interface with about 2200 field data points. The data communications network that has been designed includes a redundant, self-healing fiber optic data highway as well as a fiber optic ethernet. Commercially available human-machine interface software running on a UNIX-based system displays facility subsystem status operator X-terminals. Project design features, methods, costs, and schedule are discussed

  5. Current developments in optical engineering and commercial optics; Proceedings of the Meeting, San Diego, CA, Aug. 7-11, 1989

    Science.gov (United States)

    Fischer, Robert E. (Editor); Pollicove, Harvey M. (Editor); Smith, Warren J. (Editor)

    1989-01-01

    Various papers on current developments in optical engineering and commercial optics are presented. Individual topics addressed include: large optics fabrication technology drivers and new manufacturing techniques, new technology for beryllium mirror production, design examples of hybrid refractive-diffractive lenses, optical sensor designs for detecting cracks in optical materials, retroreflector field-of-view properties for open and solid cube corners, correction of misalignment-dependent aberrations of the HST via phase retrieval, basic radiometry review for seeker test set, radiation effects on visible optical elements, and nonlinear simulation of efficiency for large-orbit nonwiggler FELs.

  6. Primary experimental studies on mid-infrared FEL irradiation on dental substances at BFEL

    CERN Document Server

    Biao, Z J; Gao Xue Ju; He Wei; Huang Yu Ying; Li Yong Gui; LiuNianQing; Wang Min Kai; Wu Gan; Yan Xue Pin; Zhang Guo Qing

    2001-01-01

    A free electron laser (FEL) with its characteristics of wide wavelength tunability, ultrashort pulse time structure, and high peak power density is predominantly superior to all other conventional lasers in applications. Several experimental studies on mid-infrared FEL irradiation on dental enamel and dentine were performed at the Beijing FEL. Experimental aims were to investigate changes in the hardness, ratios of P to Ca and Cs before and after irradiation on samples with a characteristic absorption wavelength of 9.66 mu m, in the colors of these sample surfaces after irradiation with different wavelengths around the peak wavelength. The time dependence of temperature of the dentine sample was measured with its ps pulse effects compared to that with a continuous CO sub 2 laser. FTIR absorption spectra in the range of 2.5-15.4 mu m for samples of these hard dental substances and pure hydroxyapatite were first examined to decide their chemical components and absorption maximums. Primary experimental results w...

  7. The Posterior Sustained Negativity Revisited—An SPN Reanalysis of Jacobsen and Höfel (2003

    Directory of Open Access Journals (Sweden)

    Thomas Jacobsen

    2018-01-01

    Full Text Available Symmetry is an important cue for the aesthetic judgment of beauty. Using a binary forced-choice format in a cued mixed design, Jacobsen and Höfel (2003 compared aesthetic judgments of beauty and symmetry judgments of novel graphic patterns. A late posterior sustained negativity elicited by symmetric patterns was observed in the symmetry judgment condition, but not in the beauty judgement condition. Therefore, this negativity appeared to be mainly driven by the task.In a series of studies, Bertamini, Makin, and colleagues observed a comparable sustained posterior negativity (SPN to symmetric stimuli, mainly taken to reflect obligatory symmetry processing independent of task requirements. We reanalyzed the data by Jacobsen and Höfel (2003 using similar parameters for data analysis as Bertamini, Makin, and colleagues to examine these apparent differences. The reanalysis confirmed both a task-driven effect on the posterior sustained negativity/SPN to symmetric patterns in the symmetry judgment condition and a strong symmetry-driven SPN to symmetric patterns. Differences between the references used for analyses of the electroencephalogram (EEG had an effect. Based on the reanalysis, the Jacobsen and Höfel (2003 data also fit well with Bertamini’s, Makin’s, and colleagues’ account of obligatory symmetry processing.

  8. Commissioning experience and beam physics measurements at the SwissFEL Injector test Facility

    CERN Document Server

    Schietinger, T.; Aiba, M.; Arsov, V.; Bettoni, S.; Beutner, B.; Calvi, M.; Craievich, P.; Dehler, M.; Frei, F.; Ganter, R.; Hauri, C. P.; Ischebeck, R.; Ivanisenko, Y.; Janousch, M.; Kaiser, M.; Keil, B.; Löhl, F.; Orlandi, G. L.; Ozkan Loch, C.; Peier, P.; Prat, E.; Raguin, J.-Y.; Reiche, S.; Schilcher, T.; Wiegand, P.; Zimoch, E.; Anicic, D.; Armstrong, D.; Baldinger, M.; Baldinger, R.; Bertrand, A.; Bitterli, K.; Bopp, M.; Brands, H.; Braun, H. H.; Brönnimann, M.; Brunnenkant, I.; Chevtsov, P.; Chrin, J.; Citterio, A.; Csatari Divall, M.; Dach, M.; Dax, A.; Ditter, R.; Divall, E.; Falone, A.; Fitze, H.; Geiselhart, C.; Guetg, M. W.; Hämmerli, F.; Hauff, A.; Heiniger, M.; Higgs, C.; Hugentobler, W.; Hunziker, S.; Janser, G.; Kalantari, B.; Kalt, R.; Kim, Y.; Koprek, W.; Korhonen, T.; Krempaska, R.; Laznovsky, M.; Lehner, S.; Le Pimpec, F.; Lippuner, T.; Lutz, H.; Mair, S.; Marcellini, F.; Marinkovic, G.; Menzel, R.; Milas, N.; Pal, T.; Pollet, P.; Portmann, W.; Rezaeizadeh, A.; Ritt, S.; Rohrer, M.; Schär, M.; Schebacher, L.; Scherrer, St.; Schlott, V.; Schmidt, T.; Schulz, L.; Smit, B.; Stadler, M.; Steffen, Bernd; Stingelin, L.; Sturzenegger, W.; Treyer, D. M.; Trisorio, A.; Tron, W.; Vicario, C.; Zennaro, R.; Zimoch, D.

    2016-10-26

    The SwissFEL Injector Test Facility operated at the Paul Scherrer Institute between 2010 and 2014, serving as a pilot plant and test bed for the development and realization of SwissFEL, the x-ray Free Electron Laser facility under construction at the same institute. The test facility consisted of a laser-driven rf electron gun followed by an S-band booster linac, a magnetic bunch compression chicane and a diagnostic section including atransverse deflecting rf cavity. It delivered electron bunchesof up to200 pC chargeand up to 250 MeV beam energy at a repetition rate of 10 Hz. The measurements performed at the test facility not only demonstrated the beam parameters required to drive the first stage of a FEL facility, but also led to significant advances in instrumentation technologies, beam characterization methods and the generation, transport and compression of ultralow-emittance beams. We give a comprehensive overview of the commissioning experience of the principal subsystems and the beam physics measureme...

  9. Energy stability in recirculating, energy-recovering linacs in the presence of a FEL

    International Nuclear Information System (INIS)

    Merminga, L.; Bisognano, J.; Delayen, J.R.

    1996-01-01

    Recirculating, energy-recovering linacs can be used as driver accelerators for high power FELs (free electron lasers). Instabilities which arise from fluctuations of the cavity fields are investigated. Energy changes can cause beam loss on apertures, or, when coupled to M 56 , phase oscillations. Both effects change the beam induced voltage in the cavities and can lead to unstable variations of the accelerating field. An analytical model which includes amplitude and phase feedback, has been developed to study the stability of the system for small perturbations from equilibrium. The interaction of the electron beam with the FEL is a major perturbation which affects both the stability of the system and development of startup and recovery scenarios. To simulate the system's response to such large parameter variations, a numerical model of the beam-cavity interaction has been developed which includes low level rf feedback, phase oscillations and beam loss instabilities and the FEL interaction. Agreement between the numerical model and the linear theory has been demonstrated in the limit of small perturbations. In addition, the model has been benchmarked against experimental data obtained during CEBAF's high current operation. Numerical simulations have been performed for the high power IR DEMO approved for construction at CEBAF

  10. High-gain Seeded FEL Amplifier Tunable in the Terahertz Range

    CERN Document Server

    Sung, C; Pellegrini, C; Ralph, J E; Reiche, S; Rosenzweig, J B; Tochitsky, Sergei Ya

    2005-01-01

    The lack of a high-power, relatively low-cost and compact terahertz (THz) source in the range 0.3-3x10(12) Hz is the major obstacle in progressing on biomedical and material studies at these wavelengths. A high-gain, single pass seeded FEL technique allows to obtain high power THz pulses of a high spectral brightness. We describe an ongoing project at the Neptune laboratory where a ~ 1kW seed pulse generated by difference frequency mixing of CO2 laser lines in a GaAs nonlinear crystal is injected into a waveguide FEL amplifier. The FEL is driven by a 5 ps (r.m.s) long electron pulse with a peak current up to 100A provided by a regular S-band photoinjector. According to 3-D, time dependent simulations, up to ~ 10 MW THz power can be generated using a 2 meter long planar undulator. By mixing different pairs of CO2 laser lines and matching resonant energy of the electron beam, tunability in the 100-400 mm range is expected. A tunable Fabri-Perot interferometer will be used to select a high-power 5ps THz pulse. T...

  11. A Coherent Compton Backscattering High Gain FEL using an X-Band Microwave Undulator

    CERN Document Server

    Pellegrini, C; Travish, G

    2005-01-01

    We describe a proposed high-gain FEL using an X-band microwave undulator and operating at a wavelength of about 0.5 μm. The FEL electron beam energy is 65 MeV. The beam is produced by the NLCTA X-band linac at SLAC, using an S-band high-brightness photoinjector. The undulator consists of a circular waveguide with an rf wave counter-propagating with respect to the electron beam. The undulator is powered with two high-power X-band klystrons and a dual-moded pulse compressor recently developed at SLAC. This system is capable of delivering flat-top rf pulses of up to 400 ns and a few hundred megawatts. The equivalent undulator period is 1.4 cm, the radius of the circular pipe is 1 cm, and the undulator parameter is about 0.4 for a helical undulator configuration, obtained using two cross-polarized TE modes, or larger for a planar configuration, using one rf polarization. The undulator is about four meters long. The FEL will reach saturation within this distance when operated in a SASE mode. We describe t...

  12. Formation of low time-bandwidth product, single-sided exponential optical pulses in free-electron laser oscillators

    NARCIS (Netherlands)

    MacLeod, A. M.; Yan, X.; Gillespie, W. A.; Knippels, G.M.H.; Oepts, D.; van der Meer, A. F. G.; Rella, C. W.; Smith, T. J.; Schwettman, H. A.

    2000-01-01

    The detailed shape of picosecond optical pulses from a free-electron laser (FEL) oscillator has been studied for various cavity detunings. For large values of the cavity detuning the optical pulse develops an exponential leading edge, with a time constant proportional to the applied cavity detuning

  13. Technical Design and Optimization Study for the FERMI at Elettra FEL Photoinjector

    International Nuclear Information System (INIS)

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

    2006-01-01

    The FERMI (at) Elettra FEL project will provide a novel, x-ray free electron laser user facility at Sincrotrone Trieste based on seeded and cascade FEL techniques. The electron beam source and injector systems play a crucial role in the success of the facility by providing the highest quality electron beams to the linac and FEL undulators. This Technical Note examines the critical technology components that make up the injector system, and demonstrates optimum beam dynamics solutions to achieve the required high quality electron beams. Section 2 provides an overview of the various systems and subsystems that comprise the photoinjector. The different operating modes of the injector are described as they pertain to the different linac configurations driven by the FEL and experimental design. For each mode, the required electron beam parameters are given. Sections 3 and 4 describe the critical beamline elements in the injector complex: the photocathode and drive laser, and the RF gun. The required drive laser parameters are given at the end of Section 3. Additional details on the design of the photoinjector drive laser systems are presented in a separate Technical Note. Design considerations for the RF gun are extensively presented in Section 4. There, we describe the variation of the cavity geometry to optimize the efficiency of the energy transfer to the electron beam. A study of the power coupling into the various cavity modes that interact within the bandwidth of the RF drive pulse is presented, followed by a study of the transient cavity response under several models and, finally, the effects on extracted beam quality. Section 5 describes the initial design for the low energy, off-axis diagnostic beamline. Beam dynamics simulations using ASTRA, elegant, and MAD are presented. Section 6 presents the optimization studies for the beam dynamics in the various operating modes. The optimized baseline configurations for the beamline and incident drive laser pulse are

  14. The theoretical study of the optical klystron free electron laser

    International Nuclear Information System (INIS)

    Yang Zhenhua

    2001-01-01

    The work of the theoretical study and numerical simulation of optical klystron free electron laser is supported by National 863 Research Development Program and National Science Foundation of China. The object of studying UV band free electron laser (FEL) is to understand the physical law of optical klystron FEL and to gain experience for design. A three-dimensional code OPFEL are made and it is approved that the code is correct completely. The magnetic field of the optical klystron, the energy modulation of the electron beam, the density modulation of the electron beam, spontaneous emission of the electron beam in optical klystron, the harmonic super-radiation of the electron beam, and the effects of the undulator magnetic field error on modulation of the electron beam energy are simulated. These results are useful for the future experiments

  15. Upgrade Of The ESRF Fluorescent Screen Monitors

    CERN Document Server

    Scheidt, K

    2003-01-01

    The ESRF injector system contains 23 Fluorescent Screen monitors: 4 in the TL-1 transferline (200 MeV), 8 in the Booster, and 11 in the TL-2 transferline (6 GeV). They are based on Chromium doped Alumina screens that are pneumatically inserted at 45o angle in the beam path with an optical system, at 90o angle, collecting and focusing the emitted light onto a low-cost CCD camera with standard 75Ω video output. Serving mainly alignment purposes in the past 10 years, the present upgrade aims at a 200 μm fwhm resolution for beam-size and profile measurements. The particularity of the Alumina screen not in vacuum but in atmosphere will be explained. Details of the mechanics, the optic system and a cost-efficient way of light flux adjustment will be given. The analysis of the factors determining the ultimate spatial resolution will show that it is dominated by the screen characteristics. Results obtained with different screen material will be presented.

  16. Alignment of Duke free electron laser storage ring and optical beam delivery system

    International Nuclear Information System (INIS)

    Emamian, M.; Hower, N.

    1999-01-01

    Duke Free Electron Laser Laboratory (DFELL) hosts a 1.1 GeV electron beam storage ring facility which is capable of generating beams in the range of nearly monochromatic gamma rays to high peak power infra red (IR) laser. In this report specifications and procedures for alignment of OK-4 /Duke storage ring FEL wiggler and optical cavity mirrors will be discussed. The OK-4 FEL lasing has demonstrated a series of world record in the last few years. In August of this year the OK-4 FEL successfully commissioned to laser at 193.7 nm. Also in this article, alignment of the γ-ray and UV optical beam delivery system that is currently in progress will be described. (authors)

  17. Upgrades and expansion of the Cornell High Energy Synchrotron Source (CHESS)

    International Nuclear Information System (INIS)

    White, Jeffrey A.

    2000-01-01

    The Cornell High Energy Synchrotron Source (CHESS) is a user-oriented National Facility that provides state-of-the-art synchrotron radiation facilities to scientists worldwide. With major new funding in 1999, we now have 5 ongoing upgrade and expansion projects: 1) a new building addition that will house a new wiggler beamline (CHESS G-line) with three new experimental stations; 2) a new more powerful wiggler source for both A and G beamlines; 3) an upgrade to the A-line optics for better heat load handling and focussing; 4) a rebuild of the F-cave optics room with new optics to handle higher machine current; and 5) a renovation to the user laboratory space surrounding the F1 and F2 crystallography stations. We expect these upgrades and a new G line Cornell faculty collaborating group to raise the level of excitement and productivity at CHESS for many years to come

  18. Optical Detection of Life on Exoplanets

    Science.gov (United States)

    Heap, Sara

    2009-01-01

    We describe what is known about the atmospheric properties (Teff, lob g, [FelH]) and fundamental properties (mass, age, and metal content) of nearby stars and how they influence the habitable zones and habitable eras of these stars. We then take an observer's point of view to assess the ability of optical telescopes to detect photosynthetic or methanogenic life on planets orbiting these stars.

  19. Ultrafast phenomena at the nanoscale: science opportunities at the SwissFEL X-ray laser

    Energy Technology Data Exchange (ETDEWEB)

    Abela, R.; Braun, H.; Ming, P.; Pedrozzi, M.; Quitmann, Ch.; Reiche, S.; Daalen, M. van; Veen, J.F. van der; Mesot, J. [Paul Scherrer Intitute (PSI), Villigen (Switzerland); Mesot, J.; Shiroka, T.; Veen, J.F. van der [Swiss Federal Institute of Technology (ETHZ), Zuerich (Switzerland); Mesot, J. [Swiss Federal Institute of Technology (EPFL), Lausanne (Switzerland)

    2009-09-15

    In today's fast-moving society, standing still is effectively synonymous with being left behind. If it is to maintain, beyond the coming 10-15 years, its high international standing as a complex of large research infrastructures, the Paul Scherrer Institute (PSI) must now lay the foundation for a competitive future. Experts worldwide foresee a strongly growing demand within science and technology for photon sources delivering ultra-short, coherent X-ray pulses. Such a source, called a free electron laser (FEL), is nothing less than a gigantic flash camera, allowing us to take a deeper look into matter than with any other machine before. By literally seeing molecules in action, scientists will be able not only to capture chemical and biological processes of direct relevance and benefit to society but also to improve them. It is a dream coming true. For the first time, it will not only be possible to take pictures of molecular structures, we will be able to make movies of their motion. The new X-ray laser project at PSI, known as SwissFEL, will be an important addition to the existing complex of PSI facilities that serve interdisciplinary and international research teams from academia and industry. The SwissFEL is an essential element of Switzerland's strategic focus and will prolong our nation's leading position in scientific research for years to come. It will attract top scientists from Switzerland and abroad, and will strengthen the position of PSI as a world-class research institute. This new high-tech facility will also provide an important incentive for Swiss industry, through which existing highly-qualified jobs will be maintained and new ones created. In this report we present a wide range of important, open questions within science and engineering disciplines that SwissFEL will contribute towards solving. These questions, which form the 'scientific case' for SwissFEL, have been identified through a range of workshops organized over

  20. Upgraded wood residue fuels 1995

    International Nuclear Information System (INIS)

    Vinterbaeck, J.

    1995-01-01

    The Swedish market for upgraded residue fuels, i.e. briquettes, pellets and wood powder, has developed considerably during the nineties. The additional costs for the upgrading processes are regained and create a surplus in other parts of the system, e.g. in the form of higher combustion efficiencies, lower investment costs for burning equipment, lower operation costs and a diminished environmental impact. All these factors put together have resulted in a rapid growth of this part of the energy sector. In 1994 the production was 1.9 TWh, an increase of 37 % compared to the previous year. In the forthcoming heating season 1995/96 the production may reach 4 TWh. 57 refs, 11 figs, 6 tabs

  1. Design, realization and test of C-band accelerating structures for the SPARC-LAB linac energy upgrade

    International Nuclear Information System (INIS)

    Alesini, D.; Bellaveglia, M.; Biagini, M.E.; Boni, R.; Brönnimann, M.; Cardelli, F.; Chimenti, P.; Clementi, R.; Di Pirro, G.; Di Raddo, R.; Ferrario, M.; Ficcadenti, L.; Gallo, A.; Kalt, R.; Lollo, V.; Palumbo, L.; Piersanti, L.; Schilcher, T.

    2016-01-01

    The energy upgrade of the SPARC-LAB photo-injector at LNF-INFN (Frascati, Italy) has been originally conceived replacing one low gradient (13 MV/m) 3 m long SLAC type S-band traveling wave (TW) section with two 1.4 m long C-band accelerating sections. Due to the higher gradients reached by such structures, a higher energy beam can be obtained within the same accelerator footprint length. The use of C-band structures for electron acceleration has been adopted in a few FEL linacs in the world, among others, the Japanese Free Electron Laser at SPring-8 and the SwissFEL at Paul Scherrer Institute (PSI). The C-band sections are traveling wave, constant impedance structures with symmetric input and output axial couplers. Their design has been optimized for the operation with a SLED RF pulse compressor. In this paper we briefly review their design criteria and we focus on the construction, tuning, low and high-power RF tests. We also illustrate the design and realization of the dedicated low level RF system that has been done in collaboration with PSI in the framework of the EU TIARA project. Preliminary experimental results appear to confirm the operation of such structures with accelerating gradients larger than 35 MV/m.

  2. Design, realization and test of C-band accelerating structures for the SPARC-LAB linac energy upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Alesini, D.; Bellaveglia, M.; Biagini, M.E.; Boni, R. [INFN Laboratori Nazionali di Frascati, Via Enrico Fermi 40, 00044, Frascati (Italy); Brönnimann, M. [Paul Scherrer Institut, 5232 Villigen (Switzerland); Cardelli, F. [INFN Sezione di Roma, P.le Aldo Moro 2, 00185, Roma (Italy); Università di Roma “La Sapienza”, P.le Aldo Moro 2, 00185, Roma (Italy); Chimenti, P.; Clementi, R.; Di Pirro, G.; Di Raddo, R.; Ferrario, M. [INFN Laboratori Nazionali di Frascati, Via Enrico Fermi 40, 00044, Frascati (Italy); Ficcadenti, L. [INFN Sezione di Roma, P.le Aldo Moro 2, 00185, Roma (Italy); Università di Roma “La Sapienza”, P.le Aldo Moro 2, 00185, Roma (Italy); Gallo, A. [INFN Laboratori Nazionali di Frascati, Via Enrico Fermi 40, 00044, Frascati (Italy); Kalt, R. [Paul Scherrer Institut, 5232 Villigen (Switzerland); Lollo, V. [INFN Laboratori Nazionali di Frascati, Via Enrico Fermi 40, 00044, Frascati (Italy); Palumbo, L. [INFN Sezione di Roma, P.le Aldo Moro 2, 00185, Roma (Italy); Università di Roma “La Sapienza”, P.le Aldo Moro 2, 00185, Roma (Italy); Piersanti, L., E-mail: luca.piersanti@lnf.infn.it [INFN Sezione di Roma, P.le Aldo Moro 2, 00185, Roma (Italy); Università di Roma “La Sapienza”, P.le Aldo Moro 2, 00185, Roma (Italy); Schilcher, T. [Paul Scherrer Institut, 5232 Villigen (Switzerland)

    2016-11-21

    The energy upgrade of the SPARC-LAB photo-injector at LNF-INFN (Frascati, Italy) has been originally conceived replacing one low gradient (13 MV/m) 3 m long SLAC type S-band traveling wave (TW) section with two 1.4 m long C-band accelerating sections. Due to the higher gradients reached by such structures, a higher energy beam can be obtained within the same accelerator footprint length. The use of C-band structures for electron acceleration has been adopted in a few FEL linacs in the world, among others, the Japanese Free Electron Laser at SPring-8 and the SwissFEL at Paul Scherrer Institute (PSI). The C-band sections are traveling wave, constant impedance structures with symmetric input and output axial couplers. Their design has been optimized for the operation with a SLED RF pulse compressor. In this paper we briefly review their design criteria and we focus on the construction, tuning, low and high-power RF tests. We also illustrate the design and realization of the dedicated low level RF system that has been done in collaboration with PSI in the framework of the EU TIARA project. Preliminary experimental results appear to confirm the operation of such structures with accelerating gradients larger than 35 MV/m.

  3. AliPDU Package Upgrade

    CERN Document Server

    "Martin, Michael

    2015-01-01

    "AliPDU Package" is a set of script, panels, and datapoints designed in WinCC to manage and monitor PDU's. PDU is an essential component in the data center, in order to make data center working properly through the monitoring of power distribution and environmental condition of the data center. In this project "AliPDU Package" is upgraded so it can be used to monitor environmental condition of data center using PDU's and external environmental sensor connected to PDU.

  4. AliPDU Package Upgrade

    CERN Document Server

    Martin, Michael

    2015-01-01

    AliPDU Package is a set of script, panels, and datapoints designed in WinCC to manage and monitor PDU's. PDU is an essential component in the data center, in order to make data center working properly through the monitoring of power distribution and environmental condition of the data center. In this project "AliPDU Package" is upgraded so it can be used to monitor environmental condition of data center using PDU's and external environmental sensor connected to PDU.

  5. The TEXT upgrade vertical interferometer

    International Nuclear Information System (INIS)

    Hallock, G.A.; Gartman, M.L.; Li, W.; Chiang, K.; Shin, S.; Castles, R.L.; Chatterjee, R.; Rahman, A.S.

    1992-01-01

    A far-infrared interferometer has been installed on TEXT upgrade to obtain electron density profiles. The primary system views the plasma vertically through a set of large (60-cm radialx7.62-cm toroidal) diagnostic ports. A 1-cm channel spacing (59 channels total) and fast electronic time response is used, to provide high resolution for radial profiles and perturbation experiments. Initial operation of the vertical system was obtained late in 1991, with six operating channels

  6. Upgrading Temelin to international standards

    International Nuclear Information System (INIS)

    Anderson, J.J.; Gisoni, G.A.; Stormer, T.D.

    1994-01-01

    The digital technology being installed to upgrade the Instrumentation and Control system at the Temelin twin VVER-1000 station in the Czech Republic will allow the plant to operate more safely because it allows key information to be organised and presented to the operators, enabling them to make better informed decisions about the status of the plant. The new system is based on proven technology previously applied at Beznau in Switzerland and Sizewell B in the UK. (author)

  7. Medical Application of Free Electron Laser Trasmittance using Hollow Optical Fiber

    CERN Document Server

    Suzuki, Sachiko; Ishii, Katsonuri

    2004-01-01

    Mid-infrared Free Electron Laser (FEL) is expected as new application for biomedical surgery. However, delivery of MIR-FEL into the body is difficult because the common glass optical fibers have strong absorption at MIR region. A good operational and flexible line for FEL is required at medical field. A Hollow optical fiber is developed for IR laser and high-power laser delivery. We evaluated the fiber for FEL transmission line. This fiber is coated with cyclic olefin polymer (COP) and silver thin film on the inside of glass capillary tube. It is 700 μm-bore and 1m in lengths. The fiber transmission loss of the measured wavelength region of 5.5 μm to 12 μm is less than 1dB/m when the fiber is straight and 1.2 dB/m when bent to radius of 20 cm. Additionally, the output beam profile and the pulse structure is not so different form incidence beam. In conclusion, the fiber is suitable for delivery of the FEL energy for applications in medical and laser surgery.

  8. Scenarios for the LHC Upgrade

    CERN Document Server

    Scandale, Walter

    2008-01-01

    The projected lifetime of the LHC low-beta quadrupoles, the evolution of the statistical error halving time, and the physics potential all call for an LHC luminosity upgrade by the middle of the coming decade. In the framework of the CARE-HHH network three principal scenarios have been developed for increasing the LHC peak luminosity by more than a factor of 10, to values above 1035 cm−2s−1. All scenarios imply a rebuilding of the high-luminosity interaction regions (IRs) in combination with a consistent change of beam parameters. However, their respective features, bunch structures, IR layouts, merits and challenges, and luminosity variation with β∗ differ substantially. In all scenarios luminosity leveling during a store would be advantageous for the physics experiments. An injector upgrade must complement the upgrade measures in the LHC proper in order to provide the beam intensity and brightness needed as well as to reduce the LHC turnaround time for higher integrated luminosity.

  9. MAST Upgrade – Construction Status

    Energy Technology Data Exchange (ETDEWEB)

    Milnes, Joe, E-mail: Joe.Milnes@ccfe.ac.uk; Ayed, Nizar Ben; Dhalla, Fahim; Fishpool, Geoff; Hill, John; Katramados, Ioannis; Martin, Richard; Naylor, Graham; O’Gorman, Tom; Scannell, Rory

    2015-10-15

    Highlights: • Outlines unique capability of MAST-U, including divertor and diagnostic capability. • Describes progress made in the manufacture and assembly of key MAST-U components. • Highlights the design challenges that have been overcome. • Lists the key lessons learned thus far in the project. - Abstract: The Mega Amp Spherical Tokamak (MAST) is the centre piece of the UK fusion research programme. In 2010, a MAST Upgrade programme was initiated with three primary objectives, to contribute to: (1) testing reactor concepts (in particular exhaust solutions via a flexible divertor allowing Super-X and other extended leg configurations); (2) adding to the knowledge base for ITER (by addressing important plasma physics questions and developing predictive models to help optimise ITER performance of ITER) and (3) exploring the feasibility of using a spherical tokamak as the basis for a fusion Component Test Facility. With the project mid-way through its construction phase, progress will be reported on a number of the critical subsystems. This will include manufacture and assembly of the coils, armour and support structures that make up the new divertors, construction of the new set coils that make up the centre column, installation of the new power supplies for powering the divertor coils and enhanced TF coil set, progress in delivering the upgraded diagnostic capability, the modification and upgrading of the NBI heating systems and the complete overhaul of the machine control infrastructure, including a new control room with full remote participation facilities.

  10. Towards novel biogas upgrading processes

    Energy Technology Data Exchange (ETDEWEB)

    Privalova, E.

    2013-06-01

    Biogas production has considerable development possibilities not only in Finland but all over the world since it it the easiest way of creating value out of various waste fractions and represents an alternative source of renewable energy. Development of efficient biogas upgrading technology has become an important issue since it improves the quality of biogas and for example facilitating its injection into the natural gas pipelines. Moreover, such upgrading contributes to resolving the issue of increasing CO{sub 2} emissions and addresses the increasing climate change concerns. Together with traditional CO{sub 2} capturing technologies a new class of recently emerged sorbents such as ionic liquids is claimed as promising media for gas separations. In this thesis, an extensive comparison of the performance of different solvents in terms of CO{sub 2} capture has been performed. The focus of the present study was on aqueous amine solutions and their mixtures, traditional ionic liquids, 'switchable' ionic liquids and poly(ionic liquid)s in order to reveal the best option for biogas upgrading. The CO{sub 2} capturing efficiency for the most promising solvents achieved values around 50-60 L CO{sub 2}/L absorbent. These values are superior to currently widely applied water wash biogas upgrading system. Regeneration of the solvent mixtures appeared to be challenging since the loss of initial efficiency upon CO{sub 2} release was in excess of 20-40 vol %, especially in the case of aqueous amine solutions. In contrast, some of the ionic liquids displayed reversible behavior. Thus, for selected 'switchable' ionic and poly(ionic liquid)s the CO{sub 2} absorption/regeneration cycles were performed 3-4 times without any notable efficiency decrease. The viscosity issue, typical for ionic liquids upon CO{sub 2} saturation, was addressed and the information obtained was evaluated and related to the ionic interactions. The occurrence of volatile organic compounds

  11. Target area for Nova upgrade: Containing ignition and beyond

    International Nuclear Information System (INIS)

    Tobin, M.T.; Smith, J.R.; Campbell, D.; Wong, D.K.; Sullivan, J.A.; Pendergrass, J.; Weinstein, B.; Klein, M.

    1991-01-01

    The Lawrence Livermore National Laboratory (LLNL) is developing a conceptual design for upgrading the Nova laser from ∼ 50 kJ to ∼ 1.8 MJ of laser energy at a wavelength of 351 nm. Anticipated target performance includes achieving ignition and possibly fusion yields to 20 MJ. The target area design represents a unique challenge since it will be operating in a regime where first wall ablation and optics damage are major issues for the first time in an ICF facility. Here we describe potential performance criteria for the facility and anticipated yield-dependent x-ray, neutron, shrapnel, and debris environments. We also briefly describe the different systems that make up the target area and discuss some of the design issues. The insignificant environmental impact Nova Upgrade (NU) operations is anticipated to have on the laboratory and surrounding area is discussed. Finally, alternate design options are described along with their potential benefits

  12. Timing and Readout Contorl in the LHCb Upgraded Readout System

    CERN Document Server

    Alessio, Federico

    2016-01-01

    In 2019, the LHCb experiment at CERN will undergo a major upgrade where its detectors electronics and entire readout system will be changed to read-out events at the full LHC rate of 40 MHz. In this paper, the new timing, trigger and readout control system for such upgrade is reviewed. Particular attention is given to the distribution of the clock, timing and synchronization information across the entire readout system using generic FTTH technology like Passive Optical Networks. Moreover the system will be responsible to generically control the Front-End electronics by transmitting configuration data and receiving monitoring data, offloading the software control system from the heavy task of manipulating complex protocols of thousands of Front-End electronics devices. The way in which this was implemented is here reviewed with a description of results from first implementations of the system, including usages in test-benches, implementation of techniques for timing distribution and latency control."

  13. PFM2: a 32 × 32 processor for X-ray diffraction imaging at FELs

    International Nuclear Information System (INIS)

    Manghisoni, M.; Re, V.; Traversi, G.; Fabris, L.; Ratti, L.; Grassi, M.; Lodola, L.; Malcovati, P.; Vacchi, C.; Pancheri, L.; Benkechcache, M. E. A.; Dalla Betta, G.-F.; Xu, H.; Verzellesi, G.; Ronchin, S.; Boscardin, M.; Batignani, G.; Bettarini, S.; Casarosa, G.; Forti, F.

    2016-01-01

    This work is concerned with the design of a readout chip for application to experiments at the next generation X-ray Free Electron Lasers (FEL). The ASIC, named PixFEL Matrix (PFM2), has been designed in a 65 nm CMOS technology and consists of 32 × 32 pixels. Each cell covers an area of 110 × 110 μm 2 and includes a low-noise charge sensitive amplifier (CSA) with dynamic signal compression, a time-variant shaper used to process the preamplifier output signal, a 10-bit successive approximation register (SAR) analog-to-digital converter (ADC) and digital circuitry for channel control and data readout. Two different solutions for the readout channel, based on different versions of the time-variant filter, have been integrated in the chip. Both solutions can be operated in such a way to cope with the high frame rate (exceeding 1 MHz) foreseen for future X-ray FEL machines. The ASIC will be bump bonded to a slim/active edge pixel sensor to form the first demonstrator for the PixFEL X-ray imager. This work has been carried out in the frame of the PixFEL project funded by Istituto Nazionale di Fisica Nucleare (INFN), Italy.

  14. Upgrader alley : oil sands fever strikes Edmonton

    International Nuclear Information System (INIS)

    Griffiths, M.; Dyer, S.

    2008-01-01

    Large-scale industrial complexes called upgraders are similar to oil refineries. Several upgraders are planned for the area just northeast of Edmonton, known as Upgrader Alley. Concerns have been expressed over the potential congestion and environmental impacts of these upgraders. Upgraders will also attract other industry, and the cumulative effects of development will have major impacts on the region, its people and the natural environment. The report provided an overview of Upgrader Alley, with reference to what is driving development; upgrading issues; what Upgrader Alley will look like; and how much water Upgrader Alley needs. The report also discussed impacts on the land, air quality, and greenhouse gases. Water demand issues were discussed with reference to impacts on the North Saskatchewan River, water levels, water quality, a water management framework, and groundwater resources. Cumulative impacts were also presented. It was concluded that if all the projects for which applications had been submitted were approved, the rapid pace of growth in Upgrader Alley would mimic that of Fort McMurray. If the rate of development were somewhat slower, there would be more time to develop and implement plans to reduce the impacts. 189 refs., 6 tabs., 14 figs

  15. PAL-XFEL soft X-ray scientific instruments and X-ray optics: First commissioning results

    Science.gov (United States)

    Park, Sang Han; Kim, Minseok; Min, Changi-Ki; Eom, Intae; Nam, Inhyuk; Lee, Heung-Soo; Kang, Heung-Sik; Kim, Hyeong-Do; Jang, Ho Young; Kim, Seonghan; Hwang, Sun-min; Park, Gi-Soo; Park, Jaehun; Koo, Tae-Yeong; Kwon, Soonnam

    2018-05-01

    We report an overview of soft X-ray scientific instruments and X-ray optics at the free electron laser (FEL) of the Pohang Accelerator Laboratory, with selected first-commissioning results. The FEL exhibited a pulse energy of 200 μJ/pulse, a pulse width of power of 10 500 was achieved. The estimated total time resolution between optical laser and X-ray pulses was <270 fs. A resonant inelastic X-ray scattering spectrometer was set up; its commissioning results are also reported.

  16. Recent Upgrades and Extensions of the ASDEX Upgrade ECRH System

    Science.gov (United States)

    Wagner, Dietmar; Stober, Jörg; Leuterer, Fritz; Monaco, Francesco; Münich, Max; Schmid-Lorch, Dominik; Schütz, Harald; Zohm, Hartmut; Thumm, Manfred; Scherer, Theo; Meier, Andreas; Gantenbein, Gerd; Flamm, Jens; Kasparek, Walter; Höhnle, Hendrik; Lechte, Carsten; Litvak, Alexander G.; Denisov, Gregory G.; Chirkov, Alexey; Popov, Leonid G.; Nichiporenko, Vadim O.; Myasnikov, Vadim E.; Tai, Evgeny M.; Solyanova, Elena A.; Malygin, Sergey A.

    2011-03-01

    The multi-frequency Electron Cyclotron Heating (ECRH) system at the ASDEX Upgrade tokamak employs depressed collector gyrotrons, step-tunable in the range 105-140 GHz. The system is equipped with a fast steerable launcher allowing for remote steering of the ECRH RF beam during the plasma discharge. The gyrotrons and the mirrors are fully integrated in the discharge control system. The polarization can be controlled in a feed-forward mode. 3 Sniffer probes for millimeter wave stray radiation detection have been installed.

  17. THE SECOND STAGE OF FERMI at ELETTRA: A SEEDED FEL IN THE SOFT X-RAY SPECTRAL RANGE

    International Nuclear Information System (INIS)

    Allaria, E.; DeNinno, G.; Fawley, W.M.

    2009-01-01

    The second stage of the FERMI FEL, named FEL-2, is based on the principle of high-gain harmonic generation and relies on a double-seeded cascade. Recent developments stimulated a revision of the original setup, which was designed to cover the spectral range between 40 and 10 nm. The numerical simulations we present here show that the nominal (expected) electron-beam performance allows extension of the FEL spectral range down to 4 nm. A significant amount of third harmonic power can be also expected. We also show that the proposed setup is flexible enough for exploiting future developments of new seed sources, e.g., high harmonic generation in gases.

  18. Femtosecond resolution timing jitter correction on a TW scale Ti:sapphire laser system for FEL pump-probe experiments.

    Science.gov (United States)

    Csatari Divall, Marta; Mutter, Patrick; Divall, Edwin J; Hauri, Christoph P

    2015-11-16

    Intense ultrashort pulse lasers are used for fs resolution pump-probe experiments more and more at large scale facilities, such as free electron lasers (FEL). Measurement of the arrival time of the laser pulses and stabilization to the machine or other sub-systems on the target, is crucial for high time-resolution measurements. In this work we report on a single shot, spectrally resolved, non-collinear cross-correlator with sub-fs resolution. With a feedback applied we keep the output of the TW class Ti:sapphire amplifier chain in time with the seed oscillator to ~3 fs RMS level for several hours. This is well below the typical pulse duration used at FELs and supports fs resolution pump-probe experiments. Short term jitter and long term timing drift measurements are presented. Applicability to other wavelengths and integration into the timing infrastructure of the FEL are also covered to show the full potential of the device.

  19. Generation of a few femtoseconds pulses in seeded FELs using a seed laser with small transverse size

    Energy Technology Data Exchange (ETDEWEB)

    Li, Heting, E-mail: liheting@ustc.edu.cn; Jia, Qika

    2016-09-11

    We propose a simple method to generate a few femtosecond pulses in seeded FELs. We use a longitudinal energy-chirped electron beam passing through a dogleg where transverse dispersion will generate a horizontal energy chirp, then in the modulator, a seed laser with narrow beam radius will only modulate the center portion of the electron beam and then short pulses at high harmonics will be generated in the radiator. Using a representative realistic set of parameters, we show that 30 nm XUV pulse based on the HGHG scheme and 9 nm soft x-ray pulse based on the EEHG scheme with duration of about 8 fs (FWHM) and peak power of GW level can be generated from a 180 nm UV seed laser with beam waist of 75 μm. This new scheme can provide an optional operation mode for the existing seeded FEL facilities to meet the requirement of short-pulse FEL.

  20. Heat treatment of long pulse operation for the JAERI ERL-FEL

    International Nuclear Information System (INIS)

    Sawamura, Masaru; Nagai, Ryoji; Kikuzawa, Nobuhiro; Hajima, Ryoichi; Minehara, Eisuke

    2005-01-01

    RF power sources are replaced from all-solid-state amplifiers to IOT amplifiers for the superconducting accelerators (SCAs) and a vacuum tube amplifier for the SHB of the JAERI ERL-FEL. A long pulse operation increased the pressure in the cryostat of the SCA. The single-cell SCA can be operated in 9% duty according to the time constant of the pressure decay in the cryostat. SHB can be operated in 4% duty which is limited by the frequency range of the tuners. The result of the ABAQUS calculation shows the more duty operation. (author)