EPAC 2006 - List of Authors

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Urakawa, J.

Paper	Title	Page
MOPCH056	Development of High Brightness Soft X-ray Source Based on Inverse Compton Scattering	166
	R. Moriyama, Y. Hama, K. Hidume, A. Oshima, T. Saito, K. Sakaue, M. Washio RISE, Tokyo H. Hayano, J. Urakawa KEK, Ibaraki S. Kashiwagi ISIR, Osaka R. Kuroda AIST, Tsukuba, Ibaraki
	Compact soft X-ray source based on inverse compton scattering have been developed at Waseda University. Using 1047nm laser light from Nd:YLF laser scattered off 4.2MeV electron beam generated from a photo-cathode rf-gun, we have already suceeded to generate the soft X-ray. The energy of this x-ray is included in the part of water window, in which absorption of water is much less than that of moleculars that organize a living body. Furthermore, this x-ray source has other features such as short pulse, proportional mono-energy and energy variableness. Because of these tures, the application to the biological microscope have been expected. However, the flux of x-ray is not satisfied for the biological microscope application. Therefore, to multiply a soft X-ray flux, we utilized multi-pass amplifier for the laser light and improved a collision chamber. In this conference, we will report the experimental results and future plans.
WEPCH097	Beam Dynamics in Compton-ring Gamma Sources	2143
	E.V. Bulyak, P. Gladkikh, V. Skomorokhov NSC/KIPT, Kharkov K. Moenig DESY Zeuthen, Zeuthen T. Omori, J. Urakawa KEK, Ibaraki F. Zimmermann CERN, Geneva
	Electron storage rings with a laser cavity are promising intensive sources of polarized hard photons to generate polarized positron beams. The dynamics of electron bunches circulating in a storage ring and interacting with high-power laser pulses is studied both analytically and by simulation. Common features and difference in the bunch behavior interacting with an extremely high power laser pulse (polarized positron source for the ILC project) and a moderate pulse (source for CLIC) are shown. Also considerations on particular lattice designs for both rings are presented.
WEPCH166	Beam Test of Thermionic Cathode X-band RF-gun and Linac for Monochromatic Hard X-ray Source	2319
	K. Dobashi, A. Fukasawa, M. D. Meng, T. Natsui, F. Sakamoto, M. Uesaka, T. Yamamoto UTNL, Ibaraki M. Akemoto, H. Hayano, T. Higo, J. Urakawa KEK, Ibaraki
	A compact hard X-ray source based on laser-electron collision is proposed. The X-band linac is introduced to realize a very compact system. 2MeV electron beam with average current 2μampere at 10 pps, 200 ns of RF pulse is generated by a thermionic cathode X-band RF-gun. Beam acceleration and X-ray generation experiment by the X-band beam line are under way.
THPCH067	Coherent Synchrotron Radiation Studies at the Accelerator Test Facility	2940
	S. De Santis, J.M. Byrd LBNL, Berkeley, California A. Aryshev, T. Naito, J. Urakawa KEK, Ibaraki M.C. Ross SLAC, Menlo Park, California
	Coherent Synchrotron Radiation (CSR) has been the object of recent experiments and is a topic of great importance for several accelerator currently in their design phase (LCLS, ILC, CIRCE). We present the results of several experimental sessions performed at the Advanced Test Facility - KEK (ATF). An infrared bolometer was used to detect the emitted infrared radiation in the 1-0.05 mm wavelength range as a function of several beam parameters (beam current, RF power, extraction timing, photoinjector laser phase). The beam energy spread was also recorded. We found that the mismatch between injected and equilibrium beam is the source of the coherent signal detected concurrently with the bunch injection.
MOPLS080	A Laser-wire System at the ATF Extraction Line	738
	S.T. Boogert, G.A. Blair, G.E. Boorman, A. Bosco, L. Deacon, C. Driouichi Royal Holloway, University of London, Surrey A. Aryshev, H. Hayano, V. Karataev, K. Kubo, N. Terunuma, J. Urakawa KEK, Ibaraki A. Brachmann, J.C. Frisch, M.C. Ross SLAC, Menlo Park, California N. Delerue JAI, Oxford S. Dixit, F.B. Foster, G.F. Gannaway, D.F. Howell, Q.M. Qureshi, A. Reichold, R. Senanayake OXFORDphysics, Oxford, Oxon L.J. Jenner Cockcroft Institute, Warrington, Cheshire T. Kamps BESSY GmbH, Berlin
	A new laser-wire system has been installed at the ATF extraction line at KEK, Tsukuba. The system aims at a micron-scale laser spot size and employs a mode-locked laser system. The purpose-built interaction chamber, light delivery optics, and lens systems are described, and the first results are presented.
MOPLS081	A Study of Laser System Requirements for Application in Beam Diagnostics and Polarimetry at the ILC	741
	S. Dixit, N. Delerue, K.J. Peach JAI, Oxford G.A. Blair, S.T. Boogert, G.E. Boorman, A. Bosco, C. Driouichi Royal Holloway, University of London, Surrey A. Brachmann, J.C. Frisch, M.C. Ross SLAC, Menlo Park, California F.B. Foster, D.F. Howell, Q.G. Quelch, Q.M. Qureshi, A. Reichold OXFORDphysics, Oxford, Oxon G.J. Hirst, I. N. Ross CCLRC/RAL, Chilton, Didcot, Oxon V. Soskov, V. Variola, Z.F. Zomer LAL, Orsay J. Urakawa KEK, Ibaraki
	Advanced laser systems will be essential for a range of diagnostics devices at the ILC. High average power, excellent stability and reliability will be crucial in order to deliver the information required to attain the necessary ILC luminosity. The key parameters are listed together with the R&D required to achieve the necessary laser system performance.
TUPCH105	Performance of a Nanometer Resolution BPM System	1256
	S. Walston, C.C. Chung, P. Fitsos, J.G. Gronberg LLNL, Livermore, California S.T. Boogert Royal Holloway, University of London, Surrey J.C. Frisch, J. May, D.J. McCormick, M.C. Ross, S. Smith, T.J. Smith SLAC, Menlo Park, California H. Hayano, Y. Honda, N. Terunuma, J. Urakawa KEK, Ibaraki Y.K. Kolomensky, T. Orimoto UCB, Berkeley, California A. Lyapin, S. Malton, D.J. Miller UCL, London R. Meller Cornell University, Department of Physics, Ithaca, New York M. Slater, M.T. Thomson, D.R. Ward University of Cambridge, Cambridge V.V. Vogel DESY, Hamburg G.R. White OXFORDphysics, Oxford, Oxon
	International Linear Collider (ILC) interaction region beam sizes and component position stability requirements will be as small as a few nanometers. It is important to the ILC design effort to demonstrate that these tolerances can be achieved – ideally using beam-based stability measurements. It has been estimated that RF cavity beam position monitors (BPMs) could provide position measurement resolutions of less than one nanometer and could form the basis of the desired beam-based stability measurement. We have developed a high resolution RF cavity BPM system. A triplet of these BPMs has been installed in the extraction line of the KEK Accelerator Test Facility (ATF) for testing with its ultra-low emittance beam. The three BPMs are rigidly mounted inside an alignment frame on variable-length struts which allow movement in position and angle. We have developed novel methods for extracting the position and tilt information from the BPM signals including a calibration algorithm which is immune to beam jitter. To date, we have been able to demonstrate a resolution of approximately 20 nm over a dynamic range of ± 20 microns. We report on the progress of these ongoing tests.
WEPCH188	Compact Picosecond Pulse Radiolysis System Using Photo-cathode RF Gun	2373
	M. Washio, Y. Hama, Y. Kamiya, M. Kawaguchi, R. Moriyama, H. Nagai, K. Sakaue RISE, Tokyo H. Hayano, J. Urakawa KEK, Ibaraki S. Kashiwagi ISIR, Osaka R. Kuroda AIST, Tsukuba, Ibaraki K.U. Ushida RIKEN, Saitama
	A very compact picosecond pulse radiolysis system has been installed and operated at Waseda University. The system is composed of a laser photo-cathode RF gun as the pump source and stable Nd:YLF laser as the white light source to probe the reaction in the picosecond region. The white light generation is performed by the non-linear effect of intense laser light with the wavelength of 1047 nm into the water cell. The experimental results with the time resolution of 18 ps by examining the time profile of hydrated electron have been obtained. The system configuration will be also presented at the conference.
WEPLS053	RF Design of a Cartridge-type Photocathode RF Gun in S-band Linac	2499
	H. Moritani, Y. Muroya, A. Sakumi, T. Ueda, M. Uesaka UTNL, Ibaraki H. Hanaki, N. Kumagai, S. Suzuki, H. Tomizawa JASRI/SPring-8, Hyogo-ken J. Sasabe Hamamatsu Photonics K.K., Hamakita, Shizuoka J. Urakawa KEK, Ibaraki
	A cartridge-type photocathode RF gun is under development in collaboration with SPring-8 and Hamamatsu Photonics. Each type of cathode (Cs2Te, Mg, diamond, Ag-Cs-O) is sealed in a cartridge-type vacuum tube. Several tubes can be installed in a vacuum chamber. The cathode in the tube is inserted into a center hole in the back plate of the RF gun by a vacuum manipulator. These cartridge-type photocathodes with high QE or sensitivity for visible lights, which are prepared in a factory, can be used for a long time without vacuum breaking. Since a load-lock system for forming a new high QE film is not needed, the cartridge-type RF gun becomes compact. We are going to introduce this cartridge-type system to our linac with the BNL-GUN-IV RF gun this summer. Now, we are calculating the gun parameters of the transmission cavity which has a back plate with a center hole 8mm in diameter with SUPERFISH and simulating the beam dynamics after modifying the beam line to install the system with PARMELA. We aim to use reliable Mg and high-QE Cs2Te and try diamond and Ag-Cs-O for radiation chemistry applications. The detailed numerical design and construction will be presented.
WEPLS060	CLIC Polarized Positron Source Based on Laser Compton Scattering	2520
	F. Zimmermann, H.-H. Braun, M. Korostelev, L. Rinolfi, D. Schulte CERN, Geneva S. Araki, Y. Higashi, Y. Honda, Y. Kurihara, M. Kuriki, T. Okugi, T. Omori, T. Taniguchi, N. Terunuma, J. Urakawa KEK, Ibaraki X. Artru, R. Chehab, M. Chevallier IN2P3 IPNL, Villeurbanne E.V. Bulyak, P. Gladkikh NSC/KIPT, Kharkov M.K. Fukuda, K. Hirano, M. Takano NIRS, Chiba-shi J. Gao IHEP Beijing, Beijing S. Guiducci, P. Raimondi INFN/LNF, Frascati (Roma) T. Hirose, K. Sakaue, M. Washio RISE, Tokyo K. Moenig DESY Zeuthen, Zeuthen H.D. Sato HU/AdSM, Higashi-Hiroshima V. Soskov LPI, Moscow V.M. Strakhovenko BINP SB RAS, Novosibirsk T. Takahashi Hiroshima University, Higashi-Hiroshima A. Tsunemi SHI, Tokyo V. Variola, Z.F. Zomer LAL, Orsay
	We describe the possible layout and parameters of a polarized positron source for CLIC, where the positrons are produced from polarized gamma rays created by Compton scattering of a 1.3-GeV electron beam off a YAG laser. This scheme is very energy effective using high finesse laser cavities in conjunction with an electron storage ring. We point out the differences with respect to a similar system proposed for the ILC.
THPCH154	Development of Pulsed Laser Super-cavity for Compact High Flux X-ray Sources	3155
	K. Sakaue, M. Washio RISE, Tokyo S. Araki, Y. Higashi, Y. Honda, T. Taniguchi, J. Urakawa KEK, Ibaraki M.K. Fukuda, M. Takano NIRS, Chiba-shi H. Sakai ISSP/SRL, Chiba N. Sasao Kyoto University, Kyoto
	Pulsed-laser super-cavity is being developed at KEK-ATF for the application of a compact high brightness x-ray source based on Laser Compton Scattering. We use a Fabry-Perot optical cavity with a pulsed laser. The cavity increases a laser effective power, and at the same time, stably makes a small laser spot in side the cavity. In addition, the pulsed-laser gives much higher peak power. Thus, this scheme will open up a new possibility for building a compact high-brightness x-ray source, when collided with an intense bunched electron beam. We are now planning to build such an x-ray source with a 50MeV multi-bunch linac and a 42cm Fabry-Perot cavity using pulse stacking technology. We actually finished construction of the 50MeV linac and will start its operation in the spring, 2006. Development of the pulsed-laser super-cavity and future plan of our compact x-ray source will be presented at the conference.