TUXXPLS —  Contributed Orals: Novel Particle Sources and Acceleration Techniques   (21-May-19   09:30—10:30)
Chair: R.W. Assmann, DESY, Hamburg, Germany
Paper Title Page
SRF Gun with Warm Photocathode  
  • I. Pinayev, I. Ben-Zvi, J.C. Brutus, T. Hayes, Y.C. Jing, V. Litvinenko, J. Ma, K. Mihara, G. Narayan, F. Severino, K. Shih, J. Skaritka, E. Wang, G. Wang
    BNL, Upton, Long Island, New York, USA
  • I. Petrushina
    SUNY SB, Stony Brook, New York, USA
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
The 113 MHz superconducting gun is used an electron source for the coherent electron cooling experiment. The unique feature of the gun is that a photocathode is held at room temperature. It allowed to preserve the quantum efficiency of Cs2KSb cathode which is adversely affected by cryogenic temperatures. Relatively low frequency permitted fully realize the accelerating field gradient what in in turn helps to achieve 10 nC charge and 0.3 microns normalized emittance. We present the achieved performance an operational experience as well.
slides icon Slides TUXXPLS1 [6.786 MB]  
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TUXXPLS2 Negative Muonium Ion Production With a C12A7 Electride Film 1175
  • M. Otani, Y. Fukao, K. Futatsukawa, N. Kawamura, T. Mibe, Y. Miyake, K. Shimomura, T. Yamazaki
    KEK, Tsukuba, Japan
  • K. Hasegawa, Y. Kondo, T. Morishita
    JAEA/J-PARC, Tokai-mura, Japan
  • T. Iijima, Y. Sue
    Nagoya University, Graduate School of Science, Chikusa-ku, Nagoya, Japan
  • H. Iinuma, Y. Nakazawa
    Ibaraki University, Ibaraki, Japan
  • K. Inami, M. Yotsuzuka
    Nagoya University, Nagoya, Japan
  • K. Ishida
    RIKEN Nishina Center, Wako, Japan
  • R. Kitamura, H.Y. Yasuda
    University of Tokyo, Tokyo, Japan
  • N. Saito
    J-PARC, KEK & JAEA, Ibaraki-ken, Japan
  Funding: This work was supported by OSPS KAKENHI Grant Numbers JP15H03666, JP 16H03987, JP18H03707.
Negative muonium ion production is one of methods to cool muons. Since its discovery in 1987 by interactions of muons with a metal foil, it has been discussed that the production efficiency would be improved using a low-work function material. C12A7 (12CaO·7AlO3) was a well-known insulator as a constituent of alumina cement, but was recently confirmed to exhibit electric conductivity by electron doping. The C12A7 electride has lower work function (2.9 eV) and it was reported that nearly the same negative current signal as that with a bi-alkali material coated metal were observed in H formation. In this poster, the negative muonium production measurement with a Al foil and C12A7 electride film will be presented.
slides icon Slides TUXXPLS2 [2.680 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-TUXXPLS2  
About • paper received ※ 30 April 2019       paper accepted ※ 22 May 2019       issue date ※ 21 June 2019  
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TUXXPLS3 The Design Optimization of the Dielectric Assist Accelerating Structure for Better Heat and Gas Transfer 1179
  • S. Mori, M. Yoshida
    KEK, Ibaraki, Japan
  • D. Sato
    AIST, Tsukuba, Ibaraki, Japan
  The dielectric-assist accelerating (DAA) structure is a dielectric-inserted normal-conducting cavity, which provides high Q value at room temperature. This accelerating structure is composed of dielectric disks and a dielectric cylindrical layer inserted in a copper cavity. For the realistic operation, the removal of heat from the dielectric cells and the vacuum evacuation of gas inside the cylindrical layers have not considered yet. In order to solve the problems, we propose the optimized design of the DAA structure, where the extended part of the dielectric disk is embedded in the copper cavity and the choke structure is applied. We show the result of the electromagnetic-field simulation of the extended DAA structure and the thermal simulation to clarify the relation between a duty factor and maximum temperature of the dielectric cells.  
slides icon Slides TUXXPLS3 [5.892 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-TUXXPLS3  
About • paper received ※ 30 April 2019       paper accepted ※ 22 May 2019       issue date ※ 21 June 2019  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)