N̄ excitation for pion propagator in nuclear matter
نویسندگان
چکیده
The particle hole and delta hole excitations are well known elementary excitation modes for pion propagator in nuclear matter. But, the excitation also involves antiparticles, namely, nucleon-antinucleon, antidelta-nucleon and delta-antinucleon excitations. These are important for high energy-momentum as well, and not studied before. In this paper, we give both the formulae and the numerical calculations for the real and the imaginary parts of these excitations. PACS number(s): 21.65.+f, 13.75.Gx, 11.10.Gh
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تاریخ انتشار 1997