用QMD模型研究晕核 11 Be+208Pb的熔合机制

通过用QMD模型研究晕核^11Be ^208Pb的近垒熔合反应，发现晕核引起的熔合反应中，并存着两种相互竞争的机制：一方面当入射晕核^11Be靠近靶核时，由于^11Be是弱束缚体系，与靶核的相互作用可使其很容易破裂或少数核子被靶核俘获形成核子转移反应，从而对于熔合表现出压制；另一方面当^11Be的少数中子进入靶核并与靶核相互作用而使得靶核有些激发，而使局部半径增大，导致熔合势垒降低，熔合截面增强。用QMD模型计算出的熔合截面与实验值基本符合，垒附近表现出增强效应。

Study of Fusion Mechanism of Halo Nuclear

We have studied the fusion reaction for 11 Be+ 208 Pb near barrier by applying QMD model, and find taht in the fusion reaction induced by halo nuclei there simultaneously exist two mechanisms competing with each other. On one hand, 11 Be is a weakly bound nuclear system and is easily broke up caused by the interaction with target, when it approaches to target, so the fusion cross section is suppressed. On the other and, several neutrons of 11 Be transfer into 208 Pb and interact with 208 Pb to cause the local radius of 208 Pb increase and result in an enhancement of fusion cross section. The fusion cross sections calculatd show an enhancement near barrier, and the calculated results agree with the experimental data reasonably well.