Role of Pauli principle and isospin composition in low-energy nuclear fusion

The Pauli exclusion principle plays a crucial role as a building block of many-body quantal systems comprised of fermions. It also induces a "Pauli repulsion" in the interaction between nuclear systems. It has been shown that the Pauli repulsion widens the nucleus-nucleus potential barrier [1,2], thus hindering sub-barrier fusion. We investigate the proton and neutron contributions to the Pauli repulsion, both in the bare potential neglecting shape polarization and transfer between the reactants, as well as in the dynamical potential obtained by accounting for such dynamical rearrangements. As the basis of our study, we utilize the Pauli kinetic energy (PKE) obtained by studying the nuclear localization function (NLF) [3,4]. Recently, this approach has been generalized to incorporate all the dynamical and time-odd terms present in the nuclear energy density functional [5]. This approach is employed in the density constrained frozen Hartree-Fock (DCFHF) and in the density constrained time-dependent Hartree-Fock (DC-TDHF) microscopic methods.