THE TWO-PION EXCHANGE NN POTENTIAL IN NUCLEAR MATTER AND NUCLEAR STABILITY

摘要

A meson exchange model of the pi pi interaction which fits free pi pi scattering data is used to calculate the interactions of pions in nuclear matter as a function of nuclear density. Polarization of the nuclear medium by the pions results in a marked increase in the s-wave pi pi attraction at low energy. The influence of this effect on the nucleon-nucleon interaction is a corresponding increase with density of the NN central potential due to the exchange of two correlated pions, resulting in an NN interaction which fails to saturate. A possible mechanism for restoring the theoretical stability of nuclear matter is explored and found to be effective. (C) 1997 Elsevier Science B.V. [References: 36]