超氚核寿命之谜及其展望（英文）  

Hypertriton Lifetime Puzzle and Its Perspective

作　　者：韩成栋 陈旭荣[2,3] 袁小华[2,3] 张红强 张鹏鸣[2,3] 张亚鹏 马越[1] HAN Chengdong;CHEN Xurong;YUAN Xiaohua;ZHANG Hongqiang;ZHANG Pengming;ZHANG Yapeng;MA Yue(RIKEN,Wako 351-0106,Japan;Institute of Modern Physics,Chinese Academy of Sciences,Lanzhou 730000,China;School of Nuclear Science and Technology,University of Chinese Academy of Sciences,Beijing 100049,China;School of Nuclear Science and Technology,Lanzhou University,Lanzhou,730000,China)

机构地区：[1]日本理化学研究所,日本和光351-0198 [2]中国科学院近代物理研究所,兰州730000 [3]中国科学院大学核科学与技术学院,北京100049 [4]兰州大学核科学与技术学院,兰州730000

出　　处：《原子核物理评论》2019年第3期273-277,共5页Nuclear Physics Review

基　　金：Grant-in-Aid for Young Scientists(A)of Japan(17H04842)~~

摘　　要：近期,基于重离子碰撞的实验组(HypHI,STAR)发表了超氚核(hypertriton)的寿命测量结果。其结果显示,超氚核的寿命比Λ超子短~30%。由于超氚核是一个非常松散的结合态,超氚核的寿命不应远离Λ超子的寿命太多。这一难以解释的现象被称为超氚核的短寿命之谜。为了从不同的实验方法检验超氚核的寿命,我们提出利用J-PARC的K-束流,通过K^-+3He→Λ3H+π~0的反应道来测量超氚核寿命的实验。本文将回顾测量超氚核寿命的主要结果,并介绍目前实验方面的最新进展。本合作组提出的原创性实验方案不会受到径迹重建效率的影响,能够为验证超氚核的寿命提供重要的实验数据。Recent heavy ion experiments(HypHI,STAR)announced surprisingly short lifetime forΛ3H mesonic weak decay(MWD),which is difficult to interpret given the fact thatΛ3H is a very loosely bound system.This intriguing issue is known as hypertriton lifetime puzzle.In order to test the lifetime of the hypertriton with different experimental methods,we propose to use the K-beam of J-PARC to measure the lifetime of the hypertriton through the reaction channel of K^-+-3He→Λ3H+π0.In this article,we will summarize the situation and introduce some recent activities aiming at solving this puzzle.Our method will not suffer from the track reconstruction efficiency as the heavy ion based experiments;thus provide an important test for the hypertriton lifetime puzzle with comparable precision.

关 键 词：超核 超氚核寿命 切伦科夫量能器 

分 类 号：O571.42[理学—粒子物理与原子核物理]