Gamow-Teller Decay of Te142 to I142

The $\ensuremath{\beta}$ decay of $^{142}\mathrm{Te}_{90}$ to $^{142}\mathrm{I}_{89}$ was investigated for the first time. The parent nucleus was produced by the in-flight fission of a $^{238}\mathrm{U}$ beam with an energy of 345 MeV per nucleon, impinging on a $^{9}\mathrm{Be}$ target at the Radioactive Isotope Beam Factory of RIKEN. Excited states in $^{142}\mathrm{I}$ were established by $\ensuremath{\beta}$-delayed $\ensuremath{\gamma}$-ray spectroscopy. The observed $({1}^{+})$ states in $^{142}\mathrm{I}$ could be interpreted to be predominantly the $\ensuremath{\nu}0{h}_{9/2}\ensuremath{\bigotimes}\ensuremath{\pi}0{h}_{11/2}$ configuration formed by a Gamow-Teller transition between a neutron in the $0{h}_{9/2}$ orbital and a proton in the $0{h}_{11/2}$ orbital. Additional features of the $({1}^{+})$ states are discussed by comparing with neighboring heavier isotones, such as $^{144}\mathrm{Cs}$ and $^{146}\mathrm{La}$. In the context of deformed shell-model calculations, the $({1}_{1}^{+})$ state is closely related to the $\ensuremath{\nu}[5,3,2]3/2\ensuremath{\bigotimes}\ensuremath{\pi}[5,5,0]1/2$ configuration, which may be related to the weak Gamow-Teller transition strength.