Role of Momentum Dependent Interaction in Fragmentation Process in Heavy Ion Collisions

To study the roIes of Momentum Dependent Interaction(MDI)in the fragmentation dtie to the coupling between the isospin dependence of the two-body collisions and MDI,we study,by using Isospin-dependent Quantum Molecular Dynamics model,the time evolutions of the variation of the△N_(imf)(△σ,U_1^(sym))with the MDI and without it(NOMDI).The quantity is defined