关键词: 
能谱 /
核子-核子碰撞截面 /
原子核阻止 /
量子分子动力学模型

摘要:  用同位旋相关的量子分子动力学(IQMD)模型计算了入射能量在30~200 MeV/u内， 不同中质比的反应系统(⁷⁶Zn+⁷⁶Zn， ⁷⁶Ge+⁷⁶Ge，⁷⁶Se+⁷⁶Se和⁷⁶Kr+⁷⁶Kr)碰撞产生的原子核阻止和反应产物能谱。 发现原子核阻止和不同方向的动能比值有很强的关联性，且可以用垂直方向和平行方向的碎片总动能比值的平方根近似地代替原子核阻止，用来提取同位旋相关介质中的核子-核子碰撞截面的信息。在核反应实验中，很容易测量到该物理量， 它是一个较好的探针。 The collision of different neutron/proton ratio， intermediate mass reaction systems(⁷⁶Zn+⁷⁶Zn， ⁷⁶Ge+⁷⁶Ge，⁷⁶Se+⁷⁶Se and ⁷⁶Kr+⁷⁶Kr) at the beam energy of 30~200 MeV/u are studied by using isospindependent quantum molecular dynamics(IQMD) model. It is found that there exists a strong relationship between nuclear stopping and the ratio of different direction kinetic energy， and nuclear stopping can be replaced by the square root of the ratio of perpendicular and parallel total kinetic energy of fragments， and it can be used to extract information of isospindependent in medium nucleonnucleon cross section. This physical quantity can be easily measured in nuclear reaction experiments， and it is a better probe.