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 temperatur...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.展开更多
基金Supported by the Fostering Program in Disciplines Possessing Novel Features for Natural Science of Sichuan University(2020SCUNL209)。
文摘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.
