Nuclear masses of neutron-deficient nuclei play an important role in our understanding of the astrophysical rapid proton $\left(rp\right)$ capture process. With the help of advanced mass spectrometers, nuclear masses of ${}^{61}\mathrm{Ga}$ and ${}^{62}\mathrm{Ge}$ were directly measured with a high precision, yielding a precise proton separation energy of $S_p=2.452\left(38\right)$ MeV for ${}^{62}\mathrm{Ge}$, which is a critical input for characterization of the waiting point ${}^{60}\mathrm{Zn}$ in the $rp$ process. Using the new $S_p$ value, the thermonuclear reaction rate and its associated uncertainties for ${}^{61}\mathrm{Ga}(p,\gamma ){}^{62}\mathrm{Ge}$ have been reevaluated. We find that our new rates are overall larger than those from the statistical models across the range of 0.1–1.8 GK. Within the temperature range of 0.1–0.45 GK the new rate exceeds the REACLIB V2.2 recommended values, whereas above 0.45 GK it falls below them. Simulations of type-I x-ray bursts using mesa demonstrate that the newly determined ${}^{61}\mathrm{Ga}(p,\gamma ){}^{62}\mathrm{Ge}$ rates have a substantial influence on the composition of the burst ashes: the maximum mass fraction increases for nuclei with A = 60–63, even reaching a level of 90% in the burst ashes, despite no significant variation in the light curve.

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• H & He induced nuclear reactions
• Nuclear astrophysics
• Nucleosynthesis in explosive environments
• Radiative capture
• 59 ≤ A ≤ 89