Author: Sakaue, K.
Paper Title Page
MOPC020 Development of an S-band Multi-cell Accelerating Cavity for RF Gun and Booster Linac 110
 
  • T. Aoki, K. Sakaue, M. Washio
    RISE, Tokyo, Japan
  • A. Deshpande
    SAMEER, Mumbai, India
  • M.K. Fukuda, N.K. Kudo, T. Takatomi, N. Terunuma, J. Urakawa
    KEK, Ibaraki, Japan
  
  Funding: Work supported by JST Quantum Beam Program
We have been de­vel­op­ing a pho­to­cath­ode rf gun. The rf gun with multi cell can pro­duce a high en­er­gy elec­tron beam, so it may be used for nu­mer­ous ap­pli­ca­tions such as medicine and in­dus­try. At Laser Un­du­la­tor Com­pact X-ray source (LUCX), we have de­vel­oped a com­pact X-ray source based on in­verse Comp­ton scat­ter­ing. Using a multi cell rf gun will make pos­si­ble for the X-ray source to use for such ap­pli­ca­tions. S-band 3.5 cell rf elec­tron gun which is 20 cm long can pro­duce more than 10 MeV elec­tron beam. Ac­cord­ing to the sim­u­la­tion, it is said that the emit­tance of 3.5 cell rf gun is as low as that of 1.6 cell rf gun. The elec­tro­mag­net­ic de­sign has been per­formed with the code Su­per­Fish, and the par­ti­cle trac­ing by Parmela. The new rf gun is al­ready in­stalled and pro­duced a high qual­i­ty elec­tron beam with en­er­gy of more than 10 MeV. As a con­se­quence of the sub­stan­tial ef­forts of de­vel­op­ing rf cav­i­ty, we de­cide to make a com­pact RF ac­cel­er­at­ing struc­ture with more cell for achiev­ing a small­er sys­tem. The mea­sure­ment re­sults of using the 3.5 cell rf gun, the de­sign of 12 cell boost­er cav­i­ty, and cur­rent sta­tus of 12 cell cav­i­ty man­u­fac­tur­ing will be pre­sent­ed at the con­fer­ence. 		 
 
TUPC058 Design of a Chirping Cell Attached RF Gun for Ultrashort Electron Generation 1129
 
  • K. Sakaue, K. Tamai, M. Washio
    RISE, Tokyo, Japan
  • J. Urakawa
    KEK, Ibaraki, Japan
  
  Funding: Work supported by JSPS Grant-in-Aid for Scientific Research (A) 10001690
We have been de­vel­op­ing an S-band pho­to­cath­ode rf elec­tron gun at Wase­da uni­ver­si­ty. Our rf-gun cav­i­ty was first­ly de­signed by BNL and then, mod­i­fied by our group. In this paper, we will in­tro­duce a newly de­signed rf-gun cav­i­ty with en­er­gy chirp­ing cell. To gen­er­ate an en­er­gy chirped elec­tron bunch, we at­tached ex­tra-cell for 1.6cell rf-gun cav­i­ty. Cav­i­ty de­sign was done by Su­per­fish and par­ti­cle trac­ing by PARMELA. By op­ti­miz­ing the chirp­ing cell, we ob­served lin­ear chirped elec­tron bunch. The front elec­tron have lower en­er­gy than rear. Then trans­port­ing about 2m, the bunch can be com­pressed down to 200f­sec elec­tron bunch with the charge of 160pC. This ul­tra­short bunch will be able to use for gen­er­at­ing CSR THz ra­di­a­tion, pump­ing some ma­te­ri­al to be stud­ied by pulse ra­di­ol­y­sis method, and so on. In this con­fer­ence, the de­sign of chirp­ing cell at­tached rf-gun, the re­sults of trac­ing sim­u­la­tion and plan of man­u­fac­tur­ing will be pre­sent­ed. 		 
 
TUPC059 Study on Energy Compensation by RF Amplitude Modulation for High Intense Electron Beam Generated by a Photocathode RF-Gun 1132
 
  • Y. Yokoyama, T. Aoki, K. Sakaue, T. Suzuki, M. Washio, T. Yamamoto
    RISE, Tokyo, Japan
  • H. Hayano, N. Terunuma, J. Urakawa
    KEK, Ibaraki, Japan
  • S. Kashiwagi
    Tohoku University, Research Center for Electron Photon Science, Sendai, Japan
  • R. Kuroda
    AIST, Tsukuba, Ibaraki, Japan
  
  Funding: Work supported by JSPS Grant-in-Aid for Scientific Research(A)10001690 and JST Quantum Beam Program.
At Wase­da Uni­ver­si­ty, we have been study­ing a high qual­i­ty elec­tron beam gen­er­a­tion and its ap­pli­ca­tion ex­per­i­ments with a Cs-Te pho­to­cath­ode RF-Gun. To gen­er­ate more in­tense and sta­ble elec­tron beam, we have been de­vel­op­ing the cath­ode ir­ra­di­at­ing UV laser which con­sists of op­ti­cal fiber am­pli­fi­er and LD pumped am­pli­fi­er. As the re­sult, more than 100 mul­ti-bunch elec­tron beam with 1nC each bunch charge was ob­tained. How­ev­er, it is con­sid­ered that the ac­cel­er­at­ing volt­age will de­crease be­cause of the beam load­ing ef­fect. So we have stud­ied the RF am­pli­tude mod­u­la­tion tech­nique to com­pen­sate the beam en­er­gy dif­fer­ence. The en­er­gy dif­fer­ence will caused by tran­sient ac­cel­er­at­ing volt­age in RF-Gun cav­i­ty and beam load­ing ef­fect. As the re­sult of this com­pen­sa­tion method, the en­er­gy dif­fer­ence has been com­pen­sat­ed to 1%p-p, while 5%p-p with­out com­pen­sa­tion. In this con­fer­ence, we will re­port the de­tails of en­er­gy com­pen­sa­tion method using the RF am­pli­tude mod­u­la­tion, the re­sults of beam ex­per­i­ments and the fu­ture plans. 		 
 
THPS090 Development of the Pulse Radiolysis System with a Supercontinuum Radiation using Photonic Crystal Fiber 3645
 
  • K.B. Ogata, R. Betto, Y. Hosaka, Y. Kawauchi, K. Sakaue, T. Suzuki, M. Washio
    RISE, Tokyo, Japan
  • S. Kashiwagi
    Tohoku University, Research Center for Electron Photon Science, Sendai, Japan
  • R. Kuroda
    AIST, Tsukuba, Ibaraki, Japan
  
  Funding: Work supported by JSPS Grant-in-Aid for Scientific Research (A) 10001690
In usage of ra­di­a­tion, it is im­por­tant to study the pro­cess of chem­i­cal ef­fects of ion­iz­ing ra­di­a­tion in a ma­te­ri­al. Pulse ra­di­ol­y­sis is a method to trace these rapid ini­tial chem­i­cal re­ac­tions by ion­iz­ing ra­di­a­tion. As a pump beam, we are using 5MeV elec­tron beam pro­duced from the S-band photo cath­ode RF-Gun. In nanosec­ond timescale pulse ra­di­ol­y­sis, it is re­quired the sta­ble probe light of a broad spec­trum. And es­pe­cial­ly in pi­cosec­ond timescale pulse ra­di­ol­y­sis, probe light should have short pulse width to use stro­bo­scop­ic method. There­fore, in order to de­vel­op a wide range of timescale ex­per­i­men­tal sys­tem, we have been de­vel­op­ing a Su­per­con­tin­u­um (SC) light as a probe light, which is gen­er­at­ed by non­lin­ear op­ti­cal pro­cess of short pulse IR laser in pho­ton­ic crys­tal fiber (PCF). As a re­sult, the SC light spec­trum is broad enough to use as a probe light. Then we tried to mea­sure the ab­sorp­tion spec­trum of hy­drat­ed elec­tron by SC light, we suc­cess­ful­ly ob­served good sig­nal-noise ratio data both nanosec­ond and pi­cosec­ond ex­per­i­ment with uni­fied pulse　ra­di­ol­y­sis sys­tem. In this con­fer­ence, we will re­port de­tails of these re­sults and fu­ture prospects. 		 
 
THPS095 Q-factor of an Open Resonator for a Compact Soft X-ray Source based on Thomson Scattering of Stimulated Coherent Diffraction Radiation 3657
 
  • A.S. Aryshev, S. Araki, M.K. Fukuda, J. Urakawa
    KEK, Ibaraki, Japan
  • V. Karataev
    JAI, Egham, Surrey, United Kingdom
  • G.A. Naumenko
    Tomsk Polytechnic University, Nuclear Physics Institute, Tomsk, Russia
  • A. Potylitsyn, L.G. Sukhikh, D. Verigin
    TPU, Tomsk, Russia
  • K. Sakaue
    RISE, Tokyo, Japan
  
  High-bright­ness and re­li­able sources in the VUV and the soft X-ray re­gion may be used for nu­mer­ous ap­pli­ca­tions in such areas as medicine, bi­ol­o­gy, bio­chem­istry, ma­te­ri­al sci­ence, etc. We have pro­posed a new ap­proach to pro­duce the in­tense beams of X-rays in the range of eV based on Thom­son scat­ter­ing of Co­her­ent Diffrac­tion Ra­di­a­tion (CDR) on a 43 MeV elec­tron beam. CDR is gen­er­at­ed when a charged par­ti­cle moves in the vicin­i­ty of an ob­sta­cle. The ra­di­a­tion is co­her­ent when its wave­length is com­pa­ra­ble to or longer than the bunch length. The CDR waves are gen­er­at­ed in an opened res­onator formed by two mir­rors. In this re­port the sta­tus of the ex­per­i­ment, the first CDR mea­sure­ments at the multi­bunch beam of the LUCX fa­cil­i­ty and gen­er­al hard­ware de­sign will be re­port­ed.