GT transitions built on excited states by establishing isomer beam experiments

• Project/Area Number: 15H03672
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: Institute of Physical and Chemical Research
• Principal Investigator: SAKAI Hideyuki 国立研究開発法人理化学研究所, 仁科加速器研究センター, 部長 (90030030)
• Co-Investigator(Renkei-kenkyūsha): YAKO Kentaro 東京大学, 理学系研究科・原子核科学研究センター, 准教授 (50361572) ; MICHIMASA Shin'ichiro 東京大学, 理学系研究科・原子核科学研究センター, 助教 (80392140)
• Research Collaborator: OTA Shinsuke 東京大学, 理学系研究科・原子核科学研究センター, 助教 ; KAWATA Keita 東京大学, 理学系研究科・原子核科学研究センター, 大学院生
• Project Period (FY): 2015-04-01 – 2018-03-31
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥15,210,000 (Direct Cost: ¥11,700,000、Indirect Cost: ¥3,510,000); Fiscal Year 2017: ¥2,470,000 (Direct Cost: ¥1,900,000、Indirect Cost: ¥570,000); Fiscal Year 2016: ¥7,150,000 (Direct Cost: ¥5,500,000、Indirect Cost: ¥1,650,000); Fiscal Year 2015: ¥5,590,000 (Direct Cost: ¥4,300,000、Indirect Cost: ¥1,290,000)
• Keywords: 実験核物理 / アイソマービーム / 破砕核反応 / ダイヤモンド検出器 / 荷電交換核反応 / ガモフテラー遷移 / 荷電交換反応

Outline of Final Research Achievements

The main aim of this research is to establish a technical method to discriminate an isomeric state via a TOF measurement in the beam line and to find a fragmentation reaction to have a large isomeric ratio.
We achieved the time resolution of 40 ps in FWHM by utilizing a diamond detector and a fast preamplifier system. This value is enough for the future isomer-(p,n) measurement. We searched for a fragmentation reaction which has a high isomer ratio R for 52Fe(12+). The systematic study was made for the primary beams of 58Ni, 59Co and 82Kr. We finally found that the fragmentation reaction of 82Kr->52Fe(12+)+10p20n has about R～35%. This R value is the minimum value that can be applied for the the future experiment.
Thus the initial aims are completely fulfilled.

Research Products

• [Presentation] 59Coの入射核破砕反応による高スピンアイソマービームの開発 (2018)
  • Author(s): 川田敬太
  • Organizer: 日本物理学会 2018年春（東京理科大学野田キャンパス）
• [Presentation] 低速RIビームを用いたLLFP核の核反応断面積測定・OEDOビームライン開発および2017年度実験 (2018)
  • Author(s): 道正新一郎
  • Organizer: 日本原子力学会２０１８年春の年会
• [Presentation] Isomer ratios in Fe Region by Projectile Fragmentation (2018)
  • Author(s): 酒井英行
  • Organizer: IVth Topical Workshop on Modern Aspects in Nuclear Structure
  • Int'l Joint Research / Invited
• [Presentation] 入射核破砕反応によるアイソマービーム開発 (2017)
  • Author(s): 川田敬太
  • Organizer: 日本物理学会春季大会
  • Place of Presentation: 大阪大学（大阪府豊中市）
  • Year and Date: 2017-03-18
• [Presentation] 58Niの入射核破砕反応による高スピンアイソマービームの開発 (2017)
  • Author(s): 川田敬太
  • Organizer: 日本物理学会 2017年秋（宇都宮大学）
• [Presentation] SHARAQ spectrometer: High-resolution spectroscopy using exotic beams and reactions (2016)
  • Author(s): Shinichiro Michimasa
  • Organizer: International nuclear physics conference (INPC2016)
  • Place of Presentation: Adelaide Convention centre(Adelaide, Australia)
  • Year and Date: 2016-09-16
  • Int'l Joint Research
• [Presentation] 多結晶ダイアモンド検出器の開発 (2016)
  • Author(s): 道正新一郎
  • Organizer: 日本物理学会
  • Place of Presentation: 東北学院大学（宮城県仙台市）
  • Year and Date: 2016-03-19