Variations of the gyromagnetic ratios of low-lying states in ¹⁹²Os

Abstract

The gyromagnetic ratios of the 2₂⁺ and 4₁⁺ states in ¹⁹²Os were measured relative to that of the 2₁⁺ level. The thin foil, perturbed γ-ray angular distribution technique was employed utilizing the transient hyperfine magnetic field present at the nuclei of these ions as they swiftly recoiled through a thin, magnetized Co foil. The states of interest were Coulomb excited using a beam of 220 MeV ⁵⁸Ni ions. The present measurements yielded ratios $\text{g(2}{}_2{}^{\mathrm{+}}\text{)}\text{g(2}{}_1{}^{\mathrm{+}}\text{)}\text{= 0.68 ± 0.08}$ and $\text{g(4}{}_1{}^{\mathrm{+}}\text{)}\text{g(2}{}_1{}^{\mathrm{+}}\text{)}\text{= 1.00 ± 0.12}$. The sizable disparity in the measured g-factors of the levels of the two low-lying bands is compared with interacting boson approximation model-based calculations, as well as with a Nilsson basis single-particle model description.