Off-shell effects in the energy dependence of the Be7(p,gamma)B8 astrophysical S factor

Abstract

I show that off-shell effects, like antisymmetrization and Be-7 distortions, can significantly influence the energy dependence of the nonresonant Be7(p,gamma)B8 astrophysical S factor at higher energies. The proper treatment of these effects results in a vitrually flat E1 component of the S factor at E_cm = 0.3-1.5 MeV energies in the present eight-body model. The energy dependence of the nonresonant S factor, predicted by the present model, is in agreement with the low-energy direct capture data and the existing high-energy Coulomb dissociation data. Irrespective of whether or not the present energy dependence is correct, off-shell effects can cause 15--20% changes in the value of S(0) extrapolated from high-energy (E_cm > 0.7 MeV) data.

9 pages, 1 figure

References in corpus (1)

• Astrophysical S-factor of the ${}^7$Be($p,\gamma {)}^8$B reaction from Coulomb dissociation of ${}^8$B

Cited by in corpus (9)

• Solar fusion cross sections II: the pp chain and CNO cycles
• Solar Fusion Cross Sections
• Tests of Transfer Reaction Determinations of Astrophysical S-Factors
• Low energy measurement of the 7Be(p,gamma)8B cross section
• Extrapolation of the astrophysical S factor for ^7Be(p,gamma)^8B to solar energies
• Models, measurements, and effective field theory: proton capture on Beryllium-7 at next-to-leading order
• Effects of B-8 size on the low-energy Be7(p,gamma)B8 cross section
• Low-lying continuum structures in B8 and Li8 in a microscopic model
• Role of spectroscopic factors in the potential-model description of the Be7(p,gamma)B8 reaction