Spectroscopic Study of Neutron-Rich Nuclei with Spin-Polarized Radioactive Nuclear Beams

2001 Fiscal Year Final Research Report Summary

• Project/Area Number: 12440065
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: 素粒子・核・宇宙線
• Research Institution: Osaka University
• Principal Investigator: SHIMODA Tadashi Graduate School of Science, Osaka University, Professor, 大学院・理学研究科, 教授 (70135656)
• Co-Investigator(Kenkyū-buntansha): MIYATAKE Hiroaki Institute of Particle and Nuclear Physics (KEK), Associate Professor, 助教授 (50190799) ; SHIMIZU Suguru Graduate School of Science, Osaka University, Research Associate, 大学院・理学研究科, 助手 (60294146) ; IZUMI Hideaki Graduate School of Science, Osaka University, Research Associate, 大学院・理学研究科, 助手 (50294153) ; FUKUDA Tomokazu Osaka Electro-communication University, Professor, 工学部, 教授 (50116092)
• Project Period (FY): 2000 – 2001
• Keywords: unstable nucleus / neutron halo / N=8 magic number / beta-delayed neutrons / level scheme / spin-parity assignment / optical pumping / EOM

Research Abstract

The exotic structure of nuclei far from the stability are attracting much interest because they provide stringent tests for our understanding of nuclei. We propose a new method to determine the spin-parities of excited states of nuclei far from the stability. The essential point is that we observe the beta-decay anisotropy from a spin polarized radioactive nucleus in coincidence with beta-delayed particles. We will apply this method to 11Li in order to investigate the disappearance of the N=8 neutron magic number in very neutron rich nuclei.
The research proposal has been approved with high priority at ISAC facility of TRIUMF in Canada, which is a state-of-the-art radioactive nuclear beam facility. In 2001 and 2002, we achieved the following preparatory works :
(1) Achieving highly polarized 11Li beam,
(2) Constructing a dedicated beam-line,
(3) Constructing detector systems for beta-rays, beta-delayed neutrons, and gamma-rays.
All will be ready by April, 2002, and the experiment is scheduled in May 2002.

Research Products

• [Publications] T.Shimoda et al.: "Spectroscopic Study of 11Be with Polarized 11Li Beam"TRIUMF Research proposal E903. (2000)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] T.Shimoda et al.: "A Spin Polarizer for Low Energy Radioactive Nuclear Beams"Proceedings of the 14th International Spin Physics Symposium SPIN2000, Osaka. October,2000,AIP Conference Proceedings. 570. 811-815 (2001)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] A Hatakeyama et al.: "Optical Pumping at the ISAC Polarizer"Proceedings of the International Workshop on Polarized Sources and Targets (PST2001), Indiana, USA, September,2001,World Scientific. (出版予定). (2002)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] C.D.P.Levy et al.: "A Highly Polarized 8Li+ Ion Beam at ISAC"Proceedings of the International Workshop on Polarized Sources and Targets (PST2001), Indiana, USA, September,2001,World Scientific. (出版予定). (2002)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] T. Shimoda et al.: "Spectroscopic Study of 11Be With Polarized 11Li Beam"TRIUMF Research Proposal E903. (2000)
  • Description: 「研究成果報告書概要(欧文)」より
• [Publications] T. Shimoda et al.: "A Spin Polarizer for Low Radioactive Nuclear Beams"Proceedings of the 14th Energy International Spin Physics Symposium SPIN2000, Osaka, October, 2000, AIP Conference Proceedings. 570. 811-815 (2001)
  • Description: 「研究成果報告書概要(欧文)」より
• [Publications] A. Hatakeyama et al.: "0ptical Pumping at the ISAC Polarizer"Proceedings of the International Workshop on Polarized Sources and Targets (PST2001), Indiana, USA, September, 2001, World Scientific. (2002)
  • Description: 「研究成果報告書概要(欧文)」より
• [Publications] C.D.P. Levy et al.: "A Highly Polarize. 8Li+ Ion Beam at ISAC"Proceedings of the International Workshop on Polarized Sources and Targets (PST2001), Indiana, USA, September, 2001, World Scientific. (2002)
  • Description: 「研究成果報告書概要(欧文)」より