Nucleon Mean Free Path in Nuclear Matter Based on Nuclear Schwinger-Dyson Formalism

A mean free path of nucleon moving through nuclear matter with kinetic energyof more than 100MeV is formulated based on the bare vertex nuclearSchwinger-Dyson (BNSD) method in the Walecka model. The self-energy which isderived from the higher order diagrams more than the forth order includes theFeynman part of propagator of energetic nucleon and grows up rapidly as anincrease of kinetic energy. To avoid too large growth of these diagrams, mesonpropagators are modified by introducing some form factors to take account of ainternal structure of hadron. It is confirmed that the mean free pathcalculated by the BNSD method agrees good with experimental data if areasonable form factor is chosen, i.e., a dipole (quadrupole) type of formfactor with a cut-off parameter about 750 MeV $\sim$ 1000 MeV (1200 MeV $\sim$1500 MeV)