FEL 2007 - Classification:FEL projects/

FEL projects

Paper	Title	Page
MOPPH048	ARC-EN-CIEL Project Electron Beam Dynamics	118
	M.-E. Couprie, A. Loulergue, C. Bruni SOLEIL, Gif-sur-Yvette
	ARC-EN-CIEL project is based on the development of fourth generation light source of high brilliance and tunable in the UV-X domain. The project will evolved into three phases leading to different light performances: first and second phases are in single pass configuration with energy of 220 MeV and 1 GeV respectively, while third phase comports recirculation loops at 1 GeV and 2 GeV. For delivering a high brilliance light source with high peak power short pulses, the high charge electron beam should have subpicoseconde duration with low emittance and energy spread. In order to keep optimal slice characteristics for light production, phase space non linearities due to optics aberrations and collective effects should be minimized. In ERL configuration, a critical consequence of collective effects is the Beam Break Up instability, which forms a feedback loop between the beam and the cavities. This contribution aims at presenting the electron beam dynamics for the ARC-EN-CIEL project in single pass and ERL configuration, especially on the conditions for minimizing non linearities and Beam Break Up instability.
MOPPH050	Status of the Undulator System of the Seeded HGHG-FEL Test Bench at MAX-lab	122
	M. Brandin, F. Lindau, D. Pugachov, S. Thorin, S. Werin MAX-lab, Lund W. Frentrup, A. Gaupp, K. Goldammer, K. Holldack, M. Scheer, J. Bahrdt BESSY GmbH, Berlin
	Within the EUROFEL Design Study a seeded HGHG-FEL will be set up at the 400 MeV linac at MAX-lab. The undulators and the dispersive section have been installed. A glass fibre based power meter system for integrated dose measurements as well as a Cherenkov system for a fast detection of electron losses have been integrated. We report on the performance of all components. Simulations on the acceptable radiation doses inside the undulator magnets will be presented. In the first step of commissioning the THz radiation as produced by the bunched electron beam inside the dispersive section will be used for the optimization of the longitudinal and transverse overlap of the electron beam and the laser beam.
MOPPH051	Nonlinear Harmonic Generation in the BESSY Soft X-Ray FEL	126
	K. Goldammer BESSY GmbH, Berlin
	Free Electron Lasers do not only radiate at the fundamental frequency, they may also radiate coherently at higher harmonics. This process is referred to as nonlinear harmonic generation or NHG. NHG is of high interest, because it extends the FEL output wavelength of FELs to several harmonics of the FEL resonant frequency. In cascaded High Gain Harmonic Generation (HGHG) FELs, harmonic radiation may be used to improve frequency-conversion and reduce the number of HGHG-stages. BESSY proposes to build a cascaded HGHG FEL with three FEL lines. They cover a wavelength range of 51 nm (Low-Energy FEL) to 1.2 nm (High-Energy FEL) and consist of up to four HGHG-stages. In this paper, we present studies of the BESSY High-Energy FEL harmonic content performed with the upgraded version of the simulation code Genesis 1.3.
MOPPH052	Output Performance of the STARS HGHG Demonstrator at BESSY	130
	K. Goldammer, A. Meseck, B. C. Kuske BESSY GmbH, Berlin
	BESSY is planning to construct a free-electron laser facility (STARS) to demonstrate cascaded high-gain harmonic generation (HGHG) FELs. A 325MeV superconducting linear accelerator will drive two HGHG-stages, where the second stage is seeded by the radiation from the first stage. Such a cascading of the HGHG scheme, originally pioneered by L. H. Yu, allows a reduction of the STARS output wavelength down to the few 10nm range. This paper describes the expected performance of the facility, the achievable wavelength range, the harmonic content of the radiation, the potential of super-radiant pulses and first considerations about the stability of the source.
MOPPH054	Small-Aperture Vacuum-Chamber Design for STARS	134
	J. Bahrdt, V. Duerr, M. Scheer, G. Wuestefeld, A. Meseck BESSY GmbH, Berlin
	To demonstrate and investigate the cascaded HGHG-scheme proposed for the BESSY Soft X-ray FEL, BESSY plans to build a test-facility called STARS consisting of two HGHG stages. The radiator in the second stage is planned as an APPLE III device which provides the highest field for a circular beam pipe. The minimum Gap of 7 mm translates into a 5 mm inner diameter of the vacuum chamber. An analysis of the impact of the wakefields and the expected vacuum profile is thus required. Results of this analysis an vacuum measurements are presented.
MOPPH055	Measurements of the Projected Normalized Transverse Emittance at PITZ	138
	G. Asova, K. Boyanov, I. Tsakov INRNE, Sofia J. W. Baehr, C. H. Boulware, H.-J. Grabosch, L. H. Hakobyan, M. Hänel, S. Khodyachykh, S. A. Korepanov, M. Krasilnikov, S. Lederer, A. Oppelt, B. Petrosyan, S. Riemann, S. Rimjaem, J. Roensch, A. Shapovalov, F. Stephan, L. Staykov DESY Zeuthen, Zeuthen K. Floettmann DESY, Hamburg R. Richter BESSY GmbH, Berlin
	The main objective of the Photo Injector Test facility at DESY in Zeuthen (PITZ) is the production of electron beams with minumum transverse emittance at 1 nC bunch charge. PITZ consists of a photo cathode RF gun, solenoids for the compensation of space charge induced emittance growth and a booster cavity. In order to study the emittance evolution along the beam line three Emittance Measurement SYstems (EMSY's) were installed downstream of the booster cavity. In a first operation periode in October 2006 the emittance was measured for moderate gun gradients of about 40 MV/m. A new gun cavity is presently installed at PITZ and conditioning up to a gradient of 60 MV/m is ongoing. In this work we present recent results from measurements of the normalized projected transverse emittance of the electron beam. The emittance is measured using the so called single slit technique. Data are presented for different gun and booster gradients, solenoid strengths and initial beam size at the cathode.
MOPPH057	Development of mm-Wave TDR Technique for Direct Estimating of the Quality of the FEL’s Resonator Mirrors
	M. Einat, B. Litvak, B. Yu. Kapilevich CJS, Ariel O. Faingersh, A. Gover University of Tel-Aviv, Faculty of Engineering, Tel-Aviv
	Radiated power of the Israeli FEL is greatly dependent on the quality of input/output mirrors of the quasi-optical resonator, where an interaction between electron beam and EM fields is taken placed. Since they are located in the close proximity to the electron beam transport area, the probability of their damaging is increased and regular diagnostics of mirror's quality is urgently required. However, such a diagnostic is time consuming due to the required vacuum-opening. The time domain reflectometry (TDR) method allows estimating the mirror’s quality by means of direct measurements of its power reflectance. We have developed the TDR's experimental set-up in 90-10⁵ GHz permitting to perform such measurements. The key element of this setup is the pulse modulated pin-switch with a rise time of 1-2 ns. The forward and backward signals have been recorded independently using the two separated detectors and Tektronix digital scope. We have investigated the TDR's patterns of various damaged mirrors and conclude that the suggested technique can be recommended for remote diagnostics and estimating their quality without vacuum opening. Israeli Ministry of Science
MOPPH058	Status of the SPARX Project	142
	D. Filippetto INFN/LNF, Frascati (Roma)
	The SPARX project consists in an Soft-X-ray-FEL facility jointly supported by MUR(Research Department of Italian Government), Regione Lazio, CNR, ENEA, INFN and the University of Roma Tor Vergata. It is the natural extension of the ongoing activities of the SPARC collaboration. The aim is the generation of electron beams characterized by ultra-high peak brightness at the energy of 1 and 2 GeV, for the first and the second phase respectively. The beam is expected to drive a single pass FEL experiment in the range of 13.5-6 nm and 6-1.5 nm, at 1 GeV and 2 GeV respectively, both in SASE and SEEDED FEL configurations. A hybrid scheme of RF and magnetic compression will be adopted, based on the expertise achieved at the SPARC. high brightness photoinjector presently under commissioning at Frascati INFN-LNF Laboratory.
MOPPH060	The Drive Laser System for CFEL	146
	Y. C. Chen, W. Li CAEP/IAE, Mianyang, Sichuan
	A reliable and compact drive system is one of the key components for the stable operation of FEL. We have developed a solid-state drive laser system to meet the requirements of the CFEL(CAEP FEL) research. The system consisted of a passive mode-locked oscillator with a timing stabilizer,a regenerative amplifier and a frequency conversion part. After the 4-th harmonics,the duration of 15 picoseconds Gaussian pulses with wavelength 266nm at a repetition rate 54.17MHz were obtained. These micropulses were contained within a macropulses envelope as long as 1 to 6μmicroseconds,which was emitted from the drive laser at a repetition rate at 3Hz,6Hz or 12Hz,one single micropulse energy as large as 4μmicroJoules was achieved. The design specifications, configuration and diode-pumped amplifier of the drive laser system are also described.
MOPPH061	Design of the PAL Test FEL Machine	149
	J. Choi, J. Y. Huang, H.-S. Kang, I. S. Ko, T.-Y. Lee, J.-S. Oh, S. J. Park, M. Kim PAL, Pohang, Kyungbuk C. M. Yim POSTECH, Pohang, Kyungbuk
	In a road to the PAL-XFEL, the 1st stage will be to build a test machine, whose design parameters are presented here. It will be a 230 MeV machine that has the target wavelength of visible range. The design details and simulation results are shown in this paper.
MOPPH062	Features of the PAL-XFEL Design	152
	J. Choi, H.-S. Kang, T.-Y. Lee PAL, Pohang, Kyungbuk
	The PAL-XFEL design has been revised since the previous conference. The 2nd bunch compressor has been moved to a higher energy to eliminate the space charge effect and the total linac energy has been increased from 3.7 GeV to 4.0 GeV. Details and reasons of these design revisions are explained in this paper.
MOPPH063	Potentialities of ELMI Device for Submillimeter Generation by Stimulated Intercavity Scattering in Planar FEM	156
	N. S. Ginzburg, N. Yu. Peskov, A. Sergeev, V. Yu. Zaslavsky, I. V. Zotova IAP/RAS, Nizhny Novgorod P. V. Kalinin, S. A. Kuznetsov, A. V. Arzhannikov BINP SB RAS, Novosibirsk
	Paper describes main features of a project on two-stage generation of submillimeter radiation at the ELMI device. This novel variant of a two-stage scheme based on stimulated intercavity scattering was proposed earlier in the paper. In accordance with the scheme, at the first stage a sheet electron beam drives a 2D Bragg free electron maser (FEM) of planar geometry to generate 4-mm pump wave. At the second stage this wave undergoes stimulated scattering at the supplementary electron beam to produce submillimeter radiation. A key feature of a proposed scheme is to use two sheet beams with a few kiloampers currents that transported in parallel channels, which are connected by a special waveguide for synchronization of beam radiation in different channels. Production of two sheet beams by one accelerator diode with two cathodes is also similar to the process of operation of the multibeam diode described in Ref.. Two-stage scheme allows us to use high power 4-mm radiation produced in the first channel by the sheet beam moving in an undulator quasi-static magnetic field, as an EM-undulator for the secondary stage FEL operating in Terahertz wave range. In the paper we describe results of theoretical and experimental investigations of various aspects of the two-stage scheme and some testing experiments on units for realization of this scheme at the ELMI device. * A. V.Arzhannikov et al. Proc. Int. Workshop, N. Novgorod, Vol.1,p.228-232,2006.** A. V.Arzhannikov et al. Digest Tech. Papers, PPPS-2001, Las Vegas, Nevada, Vol.1, p.561-564,2001.
MOPPH064	A Project of SC ERL at KAERI	160
	Y. H. Han, Y. U. Jeong, B. C. Lee, S. H. Park KAERI, Daejon S. V. Miginsky, A. V. Bondarenko BINP SB RAS, Novosibirsk
	A project of an ERL at Korea Atomic Energy Research Institute is described. The ERL will be connected to the existing machine without any modification. It consists of two 180° bents and two straight sections: one is for an FEL, another for a Compton X-ray source. One can choose the regime controlling the lenses. The total ERL is isochronous to avoid any problem with longitudinal beam instability. It will be possible to control both Sx and Sy transormation matrix elements independently to suppress longitudinal beam instability and allow the increase of beam current. Sextuples will be installed in bents to suppress chromatic aberration. This design provides operation in FEL regime with high electron efficiency in the range of electron energies 12–22 MeV.
MOPPH068	The NCAS-FEL: an FEL Oscillator with High Slippage	163
	K.-J. Boller, E. van Geijin Mesa+, Enschede J. Jalink, W. J. van der Zande Radboud University Nijmegen, Institute of Molecules and Materials, Nijmegen P. J.M. van der Slot Twente University, Laser Physics and Non-Linear Optics Group, Enschede
	In normal operation of FEL oscillators with little or no slippage, the cavity length needs to be slightly smaller than the synchronous value due to the lethargy in the gain build-up. If the FEL experiences high slippage, i.e., when the slippage becomes comparable or even larger than the length of the electron pulse, a different cavity detuning may be required. We use the one dimensional Medusa1D code to study the NCAS-FEL* as an example of an FEL oscillator having high slippage. Medusa1d is basically equal to the fully three dimensional Medusa code with the 3D effects stripped out. It includes multiple wiggler segments, electron beam transport elements, harmonics and a simple oscillator model. Medusa1D can also include 3D effects using the fitting formula of Xie. The NCAS-FEL is a RF-linac based FEL dedicated for high resolution spectroscopic studies in the wavelength range from 100 micron to 1.5 mm. The design of the NCAS-FEL is currently under way, and we report here initial results of this design and focus on the effects of high slippage on cavity detuning and the development of coherence within the optical pulse. Proceedings of FEL 2006, Berlin, Germany (2006) p485 - 487 Phys. Rev. ST-AB 8, 110701 (2005)* Nucl. Instrum. Methods Phys. Res., Sect. A 445, 59 (2000)
MOPPH069	3D Modelling of the ERLP IR-FEL	167
	J. A. Clarke, N. Thompson, D. J. Dunning STFC/DL/ASTeC, Daresbury, Warrington, Cheshire B. W.J. McNeil USTRAT/SUPA, Glasgow
	An Energy Recovery Linac Prototype (ERLP) facility is currently being commissioned at Daresbury Laboratory; it serves as a testbed for technologies to be used in the proposed 4th Generation Light Source (4GLS) facility. As part of the ERLP facility, an infra-red oscillator FEL is due to be commissioned early in 2008. In this paper we present full three dimensional, time-dependent modelling of the ERLP IR-FEL using Genesis 1.3 in combination with a paraxial optical propagation code (OPC). We also discuss how this work will be used to inform commissioning of the FEL.
MOPPH074	Preliminary Design of the Proposed IR-FEL in India	179
	V. Kumar, S. Krishnagopal RRCAT, Indore (M. P.)
	We propose to build a infra-red free-electron laser facility in India. We present details of the preliminary design of the FEL.
WEPPH059	FELICE: the Free Electron Laser for Intra-cavity Experiments
	B. Redlich, A. F.G. van der Meer FOM Rijnhuizen, Nieuwegein
	In this poster presentation we will discuss the objectives of the FELICE project, its design and construction, as well as the results of the recent commissioning phase.
FRAAU01	Source of Radiation on ARC-EN-CIEL Proposal	505
	O. V. Chubar, M. Labat, G. Lambert, O. Marcouillé, M.-E. Couprie SOLEIL, Gif-sur-Yvette
	The ARC-EN-CIEL project proposes a panoply of light sources for the scientific community. The phase 1 (220 MeV superconducting Linac, down to 30 nm) and phase 2 (1 GeV, down to 1 nm) choice to provide 30-100 fs HGHG radiation and their Non Linear Harmonics seeded with the High order Harmonics generated in Gas is further confirmed with the suceesfull demonstration experiment of such a scheme at SPA. New optimizations of the undulatros lead to in vacuum undulators of period 26 mm for the modulator, and APPLE-type radiators of period 30 mm, close to the standard SOLEIL insertion devices. New calculations have been carried out using PERSEO TD and GENESIS coupled to SRW for further propagation of the FEL wavefront to the beamlines. In addition, THz radiation from the magnets of the compression chicanes will be provided and has been calculated using SRW. ARC-EN-CIEL Phase 3 incorporates ERL loops, for hard X ray spontaneous emission above 10 keV from short period in vacuum undulators (20 mm period typically), one Soft-X ray spontaneous emission beamline using an variable polarisation undulator, and an FEL oscillator in the 10-60 nm spectral range. Recent calculations and optimisations will be presented.
	Slides
FRAAU02	Status of the FEL Test Facility at MAX-lab	513
	M. Abo-Bakr, J. Bahrdt, K. Goldammer BESSY GmbH, Berlin M. Brandin, F. Lindau, D. Pugachov, S. Thorin, S. Werin MAX-lab, Lund A. L'Huillier Lund University, Division of Atomic Physics, Lund
	An FEL test facility is built on the existing MAX-lab linac system in collaboration between MAX-lab and BESSY. The goal is to study and analyse seeding, harmonic generation, beam compression and diagnostic techniques with the focus of gaining knowledge and experience for the MAX IV FEL and the BESSY FEL projects. The test facility will in the first stage be using the 400 MeV linac beam to generate the third harmonic at 90 nm from a 266 nm Ti:SA seed laser. The optical klystron is installed and magnetic system, gun and seed laser systems are currently being finalised. Start-to-end simulations have been performed and operation modes for bunch compression defined. The linac and beam transport system is already in operation. We report the status and layout of the project, the issues to be addressed, the solutions for bunch compression and operation. We also report on the prospects of extending the seeding to HHG laser systems.
	Slides
FRAAU03	Compact Ring FEL as a Source of High Power Infrared Radiation	517
	A. N. Matveenko, N. Vinokurov, O. A. Shevchenko BINP SB RAS, Novosibirsk
	Ring FELs* were proposed mainly to improve the quality of radiation of x-ray FELs. Their main advantage is the absence of mirrors. It appears that this advantage is also useful for high power FELs. Another reason to build infrared ring FEL is the proof-of-principle for shorter wavelength FELs. Therefore we considered the scheme of infrared ring FEL which requires ERL with beam energy 50 MeV. Using extensive simulations we developed requirements for electron beam parameters and magnetic system of ring FEL. In spite of rather compact design such FEL may provide more than 10 kW average power. * N. A. Vinokurov, O. A. Shevchenko, NIM A528 (2004) 491-496
	Slides
FRAAU04	Re-Commissioning of the Far-Infrared Free Electron Laser for Stable and High Power Operation after the Renewal of the L-Band Linac at ISIR, Osaka University	521
	T. Igo, S. Kashiwagi, R. Kato, M. Morio, G. Isoyama ISIR, Osaka
	We have been developing a far-infrared FEL since late 1980s based on the 40 MeV, L-band electron linac at the Institute of Scientific and Industrial Research (ISIR), Osaka University. The first lasing was obtained at 32~40 um in 1994 and since then we progressively modified the FEL system and continued experiment in between to expand the wavelength region toward the longer wavelength. We finally obtained lasing at 150 um in 1998. We could not obtain power saturation because the macropulse duration is 2 us, though the RF pulse is 4 us long, due to a long filling time of the acceleration tube of the L-band linac and the number of amplification times is limited to 50 only. The linac was constructed approximately 30 years ago and it was not suitable for stable and high power operation of FEL, so that we suspended the development of the FEL. In 2002, we had an opportunity to remodel the linac largely for higher stability and reproducibility of operation. We also added a new operation mode for FEL in which the macropulse duration can be extended to 8 us. I took time to remodel the linac and commission it, but finally the operation mode for FEL is being commissioned and we are resuming the FEL again after the long suspension. We will report the progress and the current status of the re-commissioning of the FEL.
	Slides
FRAAU05	4GLS: a Facility for the Generation of High Brightness, Variably Synchronised Sources from THz into the XUV
	J. A. Clarke, D. J. Dunning, N. Thompson STFC/DL/ASTeC, Daresbury, Warrington, Cheshire B. Sheehy Sheehy Scientific Consulting, Wading River, New York B. W.J. McNeil USTRAT/SUPA, Glasgow
	The proposed 4th Generation Light Source (4GLS) at the UK’s Daresbury Laboratory is now in its Technical Design phase. The facility will employ three FELs along with conventional lasers and spontaneous synchrotron radiation sources to provide users with a uniquely flexible range of pump-probe options from THz into the XUV regions of the spectrum. A summary of the current design and operating parameters with particular emphasis on the FEL systems are presented.
	Slides