Temperature and volume dependence of pion-pion scattering lengths  

作　　者：王庆武 郭华忠 Qing-Wu Wang;Hua-Zhong Guo(Department of Physics,Sichuan University,Chengdu 610064,China)

机构地区：[1]Department of Physics,Sichuan University,Chengdu 610064,China

出　　处：《Chinese Physics C》2024年第2期36-44,共9页中国物理C（英文版）

基　　金：Supported by the Fostering Program in Disciplines Possessing Novel Features for Natural Science of Sichuan University(2020SCUNL209)。

摘　　要：The s-wave pion-pion scattering lengths a0 and a2 are studied at finite temperature and in finite spatial volume under the framework of the Nambu-Jona-Lasinio model.The behavior beyond the pseudo transition temperature is investigated using proper time regularization.The scattering length a0 exhibits singularity near the Mott temperature,and a2 is a continuous but non-monotonic function of temperature.We present the effect of finite volume on the scattering length and find that a0 can be negative and its singularity disappears at small volumes,which may hint at the existence of a chiral phase transition with decreasing volume.

关 键 词：scattering length finite volume effect chiral phase transition 

分 类 号：O572.243[理学—粒子物理与原子核物理]