Production and decay spectra of hypernuclei, and hyperons in nuclear matter

2015 Fiscal Year Final Research Report

• Project/Area Number: 25400278
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: Osaka Electro-Communication University
• Principal Investigator: HARADA Toru 大阪電気通信大学, 工学部, 教授 (70238187)
• Co-Investigator(Kenkyū-buntansha): HIRABAYASHI Yoshiharu 北海道大学, 情報基盤センター, 准教授 (60271714)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: ハイパー核 / ストレンジネス / 核反応 / チャネル結合法 / 相互作用 / 共鳴状態 / シグマ粒子 / 少数体系

Outline of Final Research Achievements

We theoretically study production and decay spectra of hypernuclear states at J-PARC experiments within a distorted-wave impulse approximation in order to see properties of hyperons in nuclear matter. The results are as follows: (1) We confirm possible existence of a Sigma NN quasi-bound state as the 1/2+ isotriplet state whose signal is clearly observed in the 3He(K-, pi-) spectrum, whereas a peak of the quasi-bound state is rather reduced in the 3He(K-, pi+) spectrum owing to the interference effects. (2) Applying the multichannel Green's function constructed by the CDCC method, we show that the calculated spectrum has the ability to fully describe Lambda-p-p breakup continuum states in 3He(K-, pi-) reactions. (3) We predict that a pole of the S-matrix for a p-wave Sigma resonant state in 4-Sigma-He is located in the complex E plane and that the shape of the conversion spectra in 4He(K-, pi-) reactions provide valuable information on Sigma N and Sigma N-Lambda N interactions.

Free Research Field

物理学，原子核理論