Near spherical shell-model structure of the21+state inAr40fromg-factor measurements

Abstract

The g factor of the ${2}_{1}^{+}$ state in $^{40}\mathrm{Ar}$ has been measured by use of Coulomb excitation in inverse kinematics and the transient magnetic-field technique. The resulting g factor, $g({2}_{1}^{+})=\ensuremath{-}0.015(42)$, is in reasonable agreement with shell-model calculations within the (full $\mathit{sd}){}_{\ensuremath{\pi}}$(full $\mathit{fp}){}_{\ensuremath{\nu}}$ space, without including core excitations. Although highly deformed admixtures in the wave function cannot be completely ruled out, they are small, in contrast to the case of $^{42}\mathrm{Ca}$.