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Pion damping width from SU(2) x SU(2) NJL model

82   0   0.0 ( 0 )
 Added by Valeri Yudichev
 Publication date 2003
  fields
and research's language is English
 Authors D. Blaschke




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Within the framework of the NJL model, we investigate the modification of the pion damping width in a hot pion gas for temperatures ranging from 0 to 180 MeV. The pion is found to broaden noticeably at T > 60 MeV. Near the chiral phase transition T ~ 180 MeV, the pion width is saturated and amounts to 70 MeV. The main contribution to the width comes from pion-pion collisions. Other contributions are found negligibly small.



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