In this paper,a phenomenological model has been suggested to explain the frictionmechanism due to partiele-hole excitation and nucleon exchange at the initial stage ofheavy ion collisions.

• 本文提出了一种唯象的模型来说明重离子在碰撞的初期阶段通过粒子-空穴激发和核子交换方式所引起的摩擦机制.