关键词: 
π弦 /
线性σ模型 /
手征相

摘要: 讨论了在LHC的Pb-Pb碰撞过程中，如果QGP SU(2)手征相变出现二级相变，那么系统将会有π弦产生，并且π弦最终将衰变为π介子。于是以上效应将导致在低动量区域（p~150—400 MeV）内的π介子增强。对应于不同的冷却温度T_f=130，120，110 MeV，产生于π弦衰变的π介子的数量分别是N^t≈270，150， 60. It is pointed out that if the QGP SU(2) chiral phase transition in the LHC PbPb collision process is taken place and the phase transition is in the second order， then pion strings will be formed， and decay. These phenomena lead to the pion enhancement in the low momentum region(p150—400 MeV) and the number of pions produced from pion string decay can be estimated about Nt≈270， 150， 60 for different freeze temperature Tf=130， 120， 110 MeV respectively.