Low-spin signature inversion in the πh9/2⊗νi13/2 oblate band of Tl190

High-spin states in $^{190}\mathrm{Tl}$ have been studied experimentally by using the $^{160}\mathrm{Gd}$($^{35}\mathrm{Cl}$,5n) fusion-evaporation reaction at beam energies of 167 and 175 MeV. A rotational band built on the $\ensuremath{\pi}{h}_{9/2}\ensuremath{\bigotimes}\ensuremath{\nu}{i}_{13/2}$ configuration with oblate deformation has been established for $^{190}\mathrm{Tl}$. Spin values are assigned by adopting the results from $\ensuremath{\alpha}\ensuremath{-}\ensuremath{\gamma}$ decay work for $^{194}\mathrm{Bi}$ found in the literature. With the configuration and spin-parity assignments, the low-spin signature inversion has been revealed for the $\ensuremath{\pi}{h}_{9/2}\ensuremath{\bigotimes}\ensuremath{\nu}{i}_{13/2}$ oblate band in $^{190}\mathrm{Tl}$. It is the first experimental observation of low-spin signature inversion for a band associated with the oblate $\ensuremath{\pi}{h}_{9/2}\ensuremath{\bigotimes}\ensuremath{\nu}{i}_{13/2}$ configuration. The low-spin signature inversion for the oblate $\ensuremath{\pi}{h}_{9/2}\ensuremath{\bigotimes}\ensuremath{\nu}{i}_{13/2}$ band can be interpreted by the two-quasiparticle-plus-rotor model including a J-dependent $p\ensuremath{-}n$ residual interaction.