Low-energy Coulomb excitation of ${}^{62}$Fe and ${}^{62}$Mn following in-beam decay of ${}^{62}$Mn

Abstract

Sub-barrier Coulomb-excitation was performed on a mixed beam of ${}^{62}$Mn and ${}^{62}$Fe, following in-trap $β^{-}$ decay of ${}^{62}$Mn at REX-ISOLDE, CERN. The trapping and charge breeding times were varied in order to alter the composition of the beam, which was measured by means of an ionisation chamber at the zero-angle position of the Miniball array. A new transition was observed at 418~keV, which has been tentatively associated to a $(2^{+},3^{+})\to 1_{g.s.}^{+}$ transition. This fixes the relative positions of the ${\hat{I}}^2$-decaying $4^{+}$ and $1^{+}$ states in ${}^{62}$Mn for the first time. Population of the $2_1^{+}$ state was observed in ${}^{62}$Fe and the cross-section determined by normalisation to the ${}^{109}$Ag target excitation, confirming the $B(E2)$ value measured in recoil-distance lifetime experiments.

9 pages, 10 figures