Metastable states from multinucleon excitations in Tl202 and Pb203

The excited level structures of $^{202}\mathrm{Tl}$ and $^{203}\mathrm{Pb}$, above the ${7}^{+}$ and $29/{2}^{\ensuremath{-}}$ isomers, respectively, have been studied. An isomer with ${I}^{\ensuremath{\pi}}={20}^{+}$ and ${T}_{1/2}=215(10)\phantom{\rule{4pt}{0ex}}\ensuremath{\mu}\mathrm{s}$ has been established in $^{202}\mathrm{Tl}$, and the level scheme extended from $I=10$ to $20\phantom{\rule{0.16em}{0ex}}\ensuremath{\hbar}$ with the placement of fifteen new transitions. In $^{203}\mathrm{Pb}$, the ${I}^{\ensuremath{\pi}}=37/{2}^{+}$ state is established to be metastable, with ${T}_{1/2}=2.5(3)\phantom{\rule{4pt}{0ex}}\mathrm{ns}$. Levels in both nuclei arise from intrinsic excitations, with likely particle-hole character for the higher-lying states in $^{203}\mathrm{Pb}$. The ${20}^{+}$ isomer in $^{202}\mathrm{Tl}$ is most likely associated with a $\ensuremath{\pi}{h}_{11/2}^{\ensuremath{-}1}$ $\ensuremath{\bigotimes}$ $\ensuremath{\nu}({i}_{13/2}^{\ensuremath{-}2},{f}_{5/2}^{\ensuremath{-}1})$ configuration, while the $37/{2}^{+}$ state in $^{203}\mathrm{Pb}$ results from the excitation of five neutrons. Calculations, using both an empirical approach and the oxbash code, have been performed to aid in the description of the excited level structure.