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

自旋极化放射性核束对富中子核的光谱研究

• 批准号: 12440065
• 负责人: SHIMODA Tadashi
• 金额: $ 9.86万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12440065/
• 关键词: unstable nucleus; neutron halo; N=8 magic number; beta-delayed neutrons; level scheme; spin-parity assignment; optical pumping; EOM; スピン編極; β遅発中性子崩壊; 励起準位; 傾斜薄膜法; 偏極電子移行反応; レーザー光ポンピング; 11Be; スピン偏極; レーザ光ポンピング

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.

远离稳定原子核的奇异结构引起了人们的极大兴趣，因为它们为我们对原子核的理解提供了严格的检验。我们提出了一种新的方法来确定远离稳定的原子核激发态的自旋对。关键的一点是，我们观察到自旋极化放射性核与β延迟粒子的衰变各向异性。我们将把这种方法应用于11Li，以研究N=8中子幻数在非常富中子核中的消失。该研究计划已在加拿大TRIUMF的ISAC设施获得高度优先批准，该设施是最先进的放射性核束设施。在2001年和2002年，我们完成了以下准备工作：(1)实现了高偏振11Li光束；(2)构建了专用光束线；(3)构建了射线、延迟中子和伽马射线探测系统。所有这些都将在2002年4月前准备就绪，实验计划在2002年5月进行。

项目成果

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)

C.D.P.Levy 等人：“ISAC 的高度极化 8Li+ 离子束”国际极化源和目标研讨会论文集 (PST2001)，美国印第安纳州，2001 年 9 月，World Scientific（即将出版）。

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)

中国民主党

C.D.P.Levy 他: "Production of a Highly Polarized 8Li+ Ion Beam at ISAC"Proceedings of the Int. Workshop on Polarized Sources and Targets (PST2001). (出版予定). (2002)

C.D.P.Levy 等人：“ISAC 的高度极化 8Li+ 离子束的生产”国际极化源和目标研讨会论文集（PST2001）（待出版）。

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)

T.Shimoda 等人：“低能放射性核束的自旋偏振器”第 14 届国际自旋物理研讨会 SPIN2000 会议记录，大阪。

T. Shimoda et al.: "Spectroscopic Study of 11Be With Polarized 11Li Beam"TRIUMF Research Proposal E903. (2000)

T. Shimoda 等人：“用偏振 11Li 光束对 11Be 进行光谱研究”TRIUMF 研究提案 E903。