Submicrosecond isomer in ${}_{\phantom{\rule{4pt}{0ex}}45}^{117}$Rh${}_{72}$ and the role of triaxiality in its electromagnetic decay rate

Submicrosecond isomer in $_{45}^{117}$ Rh $_{72}$ and the role of triaxiality in its electromagnetic decay rate

S. Lalkovski et al.

Phys. Rev. C 88, 024302 – Published 2 August 2013

Abstract

The neutron-rich nucleus $^{117}$ Rh was synthesized in the fission of a relativistic $^{238}$ U beam produced at the GSI laboratory in Darmstadt, Germany. An isomeric state with $t_{1 / 2} = 138 (17)$ ns decaying by a single $γ$ ray was observed, providing the first information on the excited states in this nucleus. The experimental data are discussed in terms of systematics and interpreted by using the Woods-Saxon deformed shell model and triaxial-rotor-plus-particle calculations. The origin of the isomer is explained as being due to a hindered $E 2$ transition to the ground state.