We point out a simple relation between the nuclear vertex constant (NVC) and the overall normalization of the astrophysical S factor. Using predicted values of the NVC for the virtual decay of 'B 'Be + p, we find S|7 (0) = 17.6 eVb for 'Be(p, y)'B reactions, consistent with the low values extrapolated from direct capture measurements by Filippone et al. and by Vaughn et al. New possibilities, using proton transfer reactions, to measure the astrophysical S factor indirectly are proposed. PACS numbers: 25.40.Lw, 25.60.+v, 95.30.CqThe Be(p, y) B reaction at solar energies (E,~0 -20 keV, E, is the center of mass energy) plays an important unique role in the "solar neutrino puzzle" [1,2], since the high energy neutrinos from the subsequent P decay of B provide about 75% of the fiux detectable in the chlorine experiment and they are the only source to which the Kamiokande experiment is sensitive. Because

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In a previous publication [Phys. Rev. Lett. 110, 112501 (2013)] we have proposed a generalization of the adiabatic model of (d, p) reactions that allows the nonlocality of the nucleon optical potential to be included in a consistent way together with the deuteron breakup. In this model an effective local d-A potential is constructed from local nucleon optical potentials taken at an energy shifted by ∼40 MeV with respect to the widely used E d /2 value, where E d is the deuteron incident energy. The effective d-A potential is shallower than that traditionally used in the analysis of (d, p) reactions within the adiabatic distorted wave approximation and this affects the calculated cross sections and the nuclear structure quantities obtained from their comparison with experimental data. In the present paper we give full derivation of the deuteron effective potential, consider its leading-order term within the local-energy approximation and discuss corrections to the leading-order term.

The low-energy reaction 14 Cn; 15 C provides a rare opportunity to test indirect methods for the determination of neutron capture cross sections by radioactive isotopes versus direct measurements. It is also important for various astrophysical scenarios. Currently, puzzling disagreements exist between the 14 Cn; 15 C cross sections measured directly, determined indirectly, and calculated theoretically. To solve this puzzle, we offer a strong test based on a novel idea that the amplitudes for the virtual 15 C ! 14 C n and the real 15 F ! 14 O p decays are related. Our study of this relation, performed in a microscopic model, shows that existing direct and some indirect measurements strongly contradict charge symmetry in the 15 C and 15 F mirror pair. This brings into question the experimental determinations of the astrophysically important (n; ) cross sections for short-lived radioactive targets.

Asymptotic normalization coefficients ͑ANCs͒ for 8 Li→ 7 Liϩn have been extracted from the neutron transfer reaction 13 C(7 Li, 8 Li) 12 C at 63 MeV. These are related to the ANCs in 8 B→ 7 Beϩp using charge symmetry. We extract ANCs for 8 B which are in very good agreement with those inferred from proton transfer and breakup experiments. We have also separated the contributions from the p 1/2 and p 3/2 components in the transfer. We find the astrophysical factor for the 7 Be(p,␥) 8 B reaction to be S 17 (0)ϭ17.6Ϯ1.7 eV b. This is the first time that the rate of a direct capture reaction of astrophysical interest has been determined through a measurement of the ANCs in the mirror system.