Author: Furukawa, K.
Paper Title Page
MOPFI018 Design Study of a New Large Aperture Flux Concentrator 318
 
  • L. Zang, M. Akemoto, S. Fukuda, K. Furukawa, T. Higo, K. Kakihara, T. Kamitani, Y. Ogawa, H. Someya, T. Takatomi
    KEK, Ibaraki, Japan
  
  For high lu­mi­nos­ity elec­tron-positron col­lid­ers, in­tense positron beam pro­duc­tion is one of the key is­sues. Flux Con­cen­tra­tor (FC) is a pulsed so­le­noid that can gen­er­ate high mag­netic field of sev­eral Tesla and is often used for fo­cus­ing positrons emerged from a pro­duc­tion tar­get. It works as an op­ti­cal match­ing de­vice in a positron cap­ture sec­tion. With this de­vice, high cap­ture ef­fi­ciency is achieved. In this paper, we will in­tro­duce a new de­sign of a FC for the Su­perKEKB positron source. The ad­van­tages of the new de­sign are: 1. the aper­ture could be dou­bled of the pre­vi­ous de­sign, 2. the trans­verse com­po­nents are only 1/10 of the pre­vi­ous de­sign, 3. main­tain the same high peak lon­gi­tu­di­nal field. The new FC mod­el­ing has been done in CST Stu­dio and we will re­port the re­sults of new FC field eval­u­a­tion. In order to cal­cu­late the positron yield and cap­ture ef­fi­ciency, a track­ing sim­u­la­tion to the end of cap­ture sec­tion has also been car­ried out, which is also in­cluded in this paper.  
 
TUPME010 High-intensity and Low-emittance Upgrade of 7-GeV Injector Linac towards SuperKEKB 1583
 
  • K. Furukawa, M. Akemoto, D.A. Arakawa, Y. Arakida, A. Enomoto, S. Fukuda, H. Honma, R. Ichimiya, N. Iida, M. Ikeda, E. Kadokura, K. Kakihara, T. Kamitani, H. Katagiri, M. Kurashina, S. Matsumoto, T. Matsumoto, H. Matsushita, S. Michizono, K. Mikawa, T. Miura, F. Miyahara, T. Mori, H. Nakajima, K. Nakao, T. Natsui, Y. Ogawa, S. Ohsawa, F. Qiu, M. Satoh, T. Shidara, A. Shirakawa, H. Sugimoto, T. Suwada, T. Takatomi, T. Takenaka, M. Tanaka, Y. Yano, K. Yokoyama, M. Yoshida, L. Zang, X. Zhou
    KEK, Ibaraki, Japan
  • D. Satoh
    TIT, Tokyo, Japan
  
  After a decade of suc­cess­ful op­er­a­tion at KEKB a new elec­tron/positron col­lider, Su­perKEKB, is being con­structed to com­mis­sion within FY2014. It aims at a lu­mi­nos­ity of 8 x 1035 /s.​cm2, 40-times higher than that of KEKB, in order to study the fla­vor physics of el­e­men­tary par­ti­cles fur­ther, by mainly squeez­ing the beams at the col­li­sion point. The in­jec­tor linac should pro­vide high-in­ten­sity and low-emit­tance beams of 7-GeV elec­tron and 4-GeV positron by newly in­stalling a RF-gun, a flux con­cen­tra­tor, and a damp­ing ring with care­ful emit­tance and en­ergy man­age­ment. It also have to per­form si­mul­ta­ne­ous top-up in­jec­tions into four stor­age rings by pulse-to-pulse beam mod­u­la­tions not to in­ter­fare be­tween three fa­cil­i­ties of Su­perKEKB, Pho­ton Fac­tory and PF-AR. This paper de­scribes the in­jec­tor de­sign de­ci­sions and pre­sent sta­tus of the con­struc­tion.  
 
WEPME017 Development and Application of the Trigger Timing Watchdog System in KEK Electron/Positron Linac 2962
 
  • M. Satoh, K. Furukawa, F. Miyahara, T. Suwada
    KEK, Ibaraki, Japan
  • T. Kudou, S. Kusano
    Mitsubishi Electric System & Service Co., Ltd, Tsukuba, Japan
  
  The KEK in­jec­tor linac pro­vides elec­trons and positrons to sev­eral ac­cel­er­a­tor fa­cil­i­ties. A 50 Hz beam-mode switch­ing sys­tem has been con­structed to re­al­ize si­mul­ta­ne­ous top-up in­jec­tions for Pho­ton Fac­tory and the KEKB high- and low-en­ergy rings, which re­quire dif­fer­ent beam char­ac­ter­is­tics. An event-based tim­ing and con­trol sys­tem was built to change the pa­ra­me­ters of var­i­ous ac­cel­er­a­tor com­po­nents within 20 ms. The com­po­nents are spread over a 600-m-long linac and re­quire changes to a total of 100 tim­ing and con­trol pa­ra­me­ters. The sys­tem has been op­er­ated suc­cess­fully since the au­tumn of 2008 and has been im­proved upon as beam op­er­a­tion ex­pe­ri­ence has been ac­cu­mu­lated. The tim­ing watch­dog and alert sys­tem are in­dis­pens­able for the sta­ble and high qual­ity beam op­er­a­tion. For this pur­pose, we de­vel­oped and uti­lized sev­eral tim­ing watch­dog sys­tem. We will pre­sent the de­tail of tim­ing sig­nal watch­dog sys­tem for the KEK in­jec­tor linac.