Magnetic moments and g-factors in odd-A Ho isotopes

Abstract: The ground-state magnetic moment, g_K factor and quenching spin gyromagnetic ratio have been calculated using the microscopic method based on the Quasiparticle Phonon Nuclear Model (QPNM) for ^155-169Ho nuclei for the first time. It is shown that the residual spin-spin interactions are responsible for the core polarization, and because of the core polarization the spin gyromagnetic factors are quenched. By considering the core polarization effects, a satisfactory agreement is obtained for the computed ground state g_K factor, which gives an intrinsic contribution to the magnetic moments. In order to assess the collective contribution to the magnetic moments, the rotational gyromagnetic factors g_R have been also calculated within the cranking approximation using the single particle wave function of the axially symmetric Woods-Saxon potential. For the ground-state magnetic moments of odd-proton ^155-165Ho nuclei, a good description of the experimental data is obtained with an accuracy of 0.01-0.1 μ_N. From systematic trends, the quenching spin gyromagnetic factor, g_K factor and magnetic moment have also been theoretically predicted for ^167,169Ho where there is no existing experimental data.