${}^{15}\mathrm{N}(p,\gamma ){}^{16}\mathrm{O}$ is one of the key reactions in the CNO cycle, which provides a link between the CN cycle and the CNO bi-cycle and determines the production of isotopes of elements such as oxygen and fluorine. Its cross sections at stellar energies are dominated by two broad $J^{\pi }=1^{-}$ resonances and the interferences between two resonances with the direct capture to the ground state, thus the proton asymptotic normalization coefficient (ANC) for the ground state in ${}^{16}\mathrm{O}$ has a significant impact on the $R$-matrix analysis for the astrophysical $S$ factor and even the determination of resonance parameters for the two $J^{\pi }=1^{-}$ states. In this work, the angular distribution of ${}^{15}\mathrm{N}({}^7\mathrm{Li},{}^6\mathrm{He}){}^{16}\mathrm{O}$ at $E_{\mathrm{lab}}=44\mathrm{MeV}$ was measured for the first time, the proton ANC for the ground state in ${}^{16}\mathrm{O}$ has been revised to be $13.24\pm 0.67{\mathrm{fm}}^{-1/2}$, and the parameters of two $1^{-}$ resonance and the astrophysical $S$ factor at zero energy have been updated based on the $R$-matrix analysis.

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• Nuclear astrophysics
• Nuclear reaction rates
• Nuclear reactions
• Radiative capture
• S-factor
• Transfer reactions
• 6 ≤ A ≤ 19