Energy and width ofΣhyperon in nuclear matter

Abstract

The width GAMMA and the potential well depth -V/sub ..sigma../ of the ..sigma.. hyperon in nuclear matter are calculated with the help of the Brueckner theory. Results obtained for GAMMA and V/sub ..sigma../ with model D of the Nijmegen baryon-baryon interaction and simple estimates of GAMMA in terms of the cross section for the ..sigma../sup -/p..--> lambda..n process are consistent with empirical estimates. It is shown that the exclusion principle and dispersive effects strongly suppress the ..sigma..N..--> lambda..N process in nuclear matter and are capable of reducing GAMMA to values suggested by recent (K,..pi..) experiments.