Momentum distributions in axially symmetric deformed nuclei: The Nilsson model

Abstract

We study velocity distributions in deformed nuclei within the Nilsson model. We analyse the condition of isotropy in momentum space as an equilibrium condition. We show results for Ne and Nd isotopes and discuss properties of overall and single-particle momentum distributions in these nuclei. We find that at the equilibrium deformation obtained with the Strutinsky method the overall momentum distribution is isotropic, or nearly isotropic, provided that ΔN ≠ 0 admixtures are taken into account in the diagonalization of the Nilsson hamiltonian. We also analyse the dependence on deformation of the single-particle and overall momentum distributions averaged over angle. We find that the dependence on the deformation of the mean field is much stronger for the single-particle momentum distributions than for the global momentum distributions. The latter are shown to be similar for spherical and deformed nuclei at equilibrium.