Cryogenic photonic assisted cavity for the accelerating strucuture with high quality factor and high electric field

• Project/Area Number: 16H02134
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Quantum beam science
• Research Institution: High Energy Accelerator Research Organization
• Principal Investigator: Yoshida Mitsuhiro 大学共同利用機関法人高エネルギー加速器研究機構, 加速器研究施設, 准教授 (60391710)
• Project Period (FY): 2016-04-01 – 2021-03-31
• Project Status: Completed (Fiscal Year 2020)
• Budget Amount: ¥41,860,000 (Direct Cost: ¥32,200,000、Indirect Cost: ¥9,660,000); Fiscal Year 2020: ¥8,190,000 (Direct Cost: ¥6,300,000、Indirect Cost: ¥1,890,000); Fiscal Year 2019: ¥8,190,000 (Direct Cost: ¥6,300,000、Indirect Cost: ¥1,890,000); Fiscal Year 2018: ¥8,190,000 (Direct Cost: ¥6,300,000、Indirect Cost: ¥1,890,000); Fiscal Year 2017: ¥8,190,000 (Direct Cost: ¥6,300,000、Indirect Cost: ¥1,890,000); Fiscal Year 2016: ¥9,100,000 (Direct Cost: ¥7,000,000、Indirect Cost: ¥2,100,000)
• Keywords: 加速器 / フォトニック / 誘電体

Outline of Final Research Achievements

The DLC coating is found to supress the secondary electron emission coefficient and to become best material for the dielecric assist accelerating structure. We adopt this coating to the minimum strucuture with 2-cell dielectric cell and applied the high power RF. Finally the high gradient of 15 MV/m was obtained in this configuration.
Further new structure with choke structure and nose was designed for the better vacuum and breakdown at contact part between cell.

Academic Significance and Societal Importance of the Research Achievements

誘電体アシスト空洞は、誘電体フォトニック構造により電磁波を内側に閉じ込める事ができ、マイクロ波の蓄積効率を非常に高くできる新しい加速構造である。これを用いる事で非常に高エネルギー効率の加速器が実現する。このような加速器は学術利用の大型加速器だけでなく、産業利用や医療応用で幅広く利用する事ができる。
また材料として使用しているセラミックは磁器と同じであり、大型の物でも任意の形状の物を安価に焼結する事が可能である。

Research Products

• [Journal Article] Multipactor suppression in dielectric-assist accelerating structures via diamondlike carbon coatings (2021)
  • Author(s): Mori Shingo、Yoshida Mitsuhiro、Satoh Daisuke
  • Journal Title: Physical Review Accelerators and Beams Volume: 24 Issue: 2 Pages: 0-11
  • DOI: 10.1103/physrevaccelbeams.24.022001
  • Peer Reviewed / Open Access
• [Journal Article] Power efficiency enhancement of dielectric assist accelerating structure (2019)
  • Author(s): Satoh Daisuke、Shibuya Tatsunori、Ogawa Hiroshi、Tanaka Masahito、Kuroda Ryunosuke、Mori Shingo、Yoshida Mitsuhiro、Toyokawa Hiroyuki
  • Journal Title: Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms Volume: 459 Pages: 148-152
  • DOI: 10.1016/j.nimb.2019.09.006
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Presentation] 誘電体アシスト型加速空洞における航跡場の減衰について (2019)
  • Author(s): 森 紳悟、吉田 光宏
  • Organizer: 第16回日本加速器学会年会
• [Presentation] The Design Optimization of the Dielectric Assist Accelerating Structure for Better Heat and Gas Transfer (2019)
  • Author(s): 森 紳悟、吉田 光宏
  • Organizer: 10th International Particle Accelerator Conference 2019
  • Int'l Joint Research
• [Presentation] MEASUREMENT OF THE SECONDARY ELECTRON-EMISSION COEFFICIENT FROM LOW-LOSS DIELECTRIC MATERIALS (2018)
  • Author(s): Shingo Mori, Mitsuhiro Yoshida, Daisuke Satoh
  • Organizer: Particle Accelerator Society of Japan
• [Presentation] THE RF GUN ADOPTING THE DIELECTRIC ASSIST ACCELERATING STRUCTURE (2018)
  • Author(s): Shingo Mori, Mitsuhiro Yoshida
  • Organizer: LINAC2018
  • Int'l Joint Research