In standard potential-model descriptions of the ${}^7\mathrm{Be}(p,\gamma {)}^8\mathrm{B}$ reaction the ${}^7\mathrm{Be}+p$ spectroscopic factors $\mathcal{S}$ appear in the cross section. We argue that the microscopic substructure effects which are represented by $\mathcal{S}$ are short-ranged and cannot affect the asymptotic normalization of the wave function. We believe that the standard way of describing reactions in a potential model may be incorrect and the low-energy cross section should not depend on $\mathcal{S}$ in the case of external capture reactions, like ${}^7\mathrm{Be}(p,\gamma {)}^8\mathrm{B}.$

• Received 30 August 1999

DOI:https://doi.org/10.1103/PhysRevC.61.037601