https://doi.org/10.1007/s100520200909
Theoretical physics
Scattering amplitude and shift in self-energy in medium
Saha Institute of Nuclear Physics, 1/AF, Bidhannagar, 700064, Calcutta, India
Two simple proofs are presented for the first order virial expansion of the self-energy of a particle moving through a medium, characterised by temperature and/or chemical potential(s). One is based on the virial expansion of the self-energy operator itself, while the other is based on the analysis of its Feynman diagrams in configuration space.
© Springer-Verlag Berlin Heidelberg / Società Italiana di Fisica, 2002