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.

远离稳定性的奇异原子核结构正引起人们的极大兴趣，因为它们为我们对原子核的理解提供了严格的测试。我们提出了一种新的方法来确定远离稳定性的核激发态的自旋奇偶性。重要的一点是，我们观察到一个自旋极化的放射性原子核的β衰变各向异性与贝塔延迟粒子相符合。我们将把这一方法应用于11Li，以研究在非常丰富的中子核中N=8中子幻数的消失。这项研究方案已经在加拿大TRIUMF的ISAC设施上获得高度优先的批准，这是一座最先进的放射性核束设施。2001年和2002年，我们完成了以下准备工作：(1)实现高偏振11Li束流，(2)建造专用束线，(3)建立β射线、β延迟中子和伽马射线探测系统，所有工作将于2002年4月准备就绪，实验计划于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。