Study of ^6,8He+p elastic scattering using the BHF formalism with three-body forces

Abstract

In the present work we have analysed the elastic scattering data of <sup>6</sup>He+p at 25.6, 38.6, 40.9 and 71 MeV/A and <sup>8</sup>He+p at 15.6, 25.6, 32.5, 66 and 72 MeV/A, using the microscopic local optical potential calculated within the framework of Brueckner-Hartree-Fock (BHF) formalism. The calculation requires mainly two inputs: (1) the nucleon-nucleon (NN) interaction and (2) the nucleon distributions in target nuclei. Realistic inter-nucleon (NN) potential Argonne v18 (AV18) along with the Urbana IX (UVIX) model of three body force with several nucleon density distributions is used in the present work for generating the nucleon-nucleus optical potential. We have used the exact method for calculating both the direct and the exchange parts of the spin-orbit potential. We reconfirm the earlier results that the spin orbit potential for these neutron rich nuclei is diffused and extended. Our results show that the different density distributions reproduce rather well the experimental differential cross sections for both isotopes, while the phenomenological density with two neutron halo gives satisfactory results for <sup>6</sup>He-p analysing power data. None of the densities used for <sup> 8</sup>He can reproduce the experimental analyzing power data. Our analysis reveals that the calculated microscopic optical potentials, with and without three body force using BHF approach provides satisfactory agreement with the elastic scattering data for <sup>6,8</sup>He+p.