Influence of ${}^{13}$C on proton-induced ${}^{13}$N production from natural carbon target

Two recent measurements of ${}^{12}$C(p,$\gamma$)${}^{13}$N reaction on natural carbon were performed by detecting ${\beta }^{+}$ decay of ${}^{13}$N residue. It is argued that the measurements at energies above the ${}^{13}$C(p,n)${}^{13}$N reaction threshold of 3.24 MeV proton kinetic energy can be interpreted as a consequence of 1.06% admixture of ${}^{13}$C isotope in natural carbon, as the cross section for ${}^{13}$N production raised by 3 orders of magnitude with respect to the measurements of ${}^{12}$C(p,$\gamma$)${}^{13}$N at lower energies.