Study of electron-nucleus scattering and nuclear electromagnetic properties based on microscopic IBM (II) theoretical approach based on ME method

In this paper a mapping of the collective state subspace in a microscopic I BM onto the fermion collective state subspace is achieved. A microscopic th eoretical method (ME method),which is suitable to deduce the boson one-body operator from the fermion one-body operator,is proposed by supposing the f orm of the boson operator and making equal the matrix elements of physical operator between the coressponding normal basis vectors of the two differen t collective state subspaces. In the context, the procedure of obtaining th e boson structure function, i.e. the determination of the boson transition charge/current density operator,is taken as an example to give a detailed s tatement of the method. Thereafter, calculations of the nuclear charge/curr ent densities can be carried out in the boson state space by taking advanta ge of the eigenfuncitons of the microscopic IBM. Associated with the formal theories of electron-nucleus scattering and nuclear electromagnetic transi tion, a microscopic approach,which can be used to study nuclear transition charge/current densities,various form factors, differential cross sections, reduced transition rates, electromagnetic multipole moments, g factors, an d so on,can be built up. Preliminary calculations of transition charge dens ity and reduced transition probability from 2(1)(+) to 0(1)(+) in Nd-146 ar e carried out in terms of the approach in the framework of microscopic sdgI BM-1. It is found that the theoretical results fit the experimental data qu ite well.