Thermal dileptons from pi-p interactions in a hot pion gas

被引:37
作者
Baier, R
Dirks, M
Redlich, K
机构
[1] UNIV WROCLAW,INST THEORET PHYS,PL-50204 WROCLAW,POLAND
[2] GSI DARMSTADT,D-64220 DARMSTADT,GERMANY
来源
PHYSICAL REVIEW D | 1997年 / 55卷 / 07期
关键词
QUARK-GLUON PLASMA; HEAVY-ION COLLISIONS; FINITE-TEMPERATURE; FIELD-THEORY; VECTOR-MESONS; PERTURBATION-SERIES; GREEN-FUNCTIONS; SOFT DILEPTONS; GAUGE-THEORIES; MASS;
D O I
10.1103/PhysRevD.55.4344
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
The production of low mass dileptons from pi-rho interactions in a hot medium is studied. Applying finite temperature perturbation theory the dilepton rate is computed up to order g(p)(2). For dilepton masses below the rho the two-body reactions pi pi-->rho gamma*, pi rho-->pi gamma*, and the decay process rho-->pi pi gamma* give significant contributions. Nonequilibrium contributions to the thermal rate are estimated, including the modification of the particle distribution function with a nonzero pion chemical potential. A comparison of the dilepton rate with the recent data measured in nucleus-nucleus collisions al CERN SPS energy by the CERES Collaboration is also performed. It is shown that the additional thermal dileptons from pi-rho interactions can partially account for the excess of the soft dilepton yield seen experimentally.
引用
收藏
页码:4344 / 4354
页数:11
相关论文
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