S17 near Zero Energy in a Direct Radiative Capture Analysis

TL;DR

This paper calculates the S17 near zero energy without relying on effective expansions or asymptotic wave functions, revealing the significant influence of nuclear potential shape on s-wave capture cross sections.

Contribution

It demonstrates that the S factor near zero energy can be accurately computed without asymptotic wave functions, challenging previous assumptions.

Findings

s-wave capture cross section is strongly affected by nuclear potential shape

d-wave contribution is non-negligible near zero energy

variations in potential parameters scarcely affect d-wave cross section below 0.1 MeV

Abstract

S17 near zero energy was calculated without using the effective expansion of the S factor or the asymptotic wave functions. Variations of the nuclear potential parameters scarcely affect the d-wave capture cross section below 0.1 MeV, but the s-wave capture cross section near zero energy is affected strongly by the shape of the nuclear potential in our calculations. This result is contrary to the existing assumption that the value of the S factor near zero energy depends on the asymptotic wave function (or asymptotic normalization coefficient). We showed that although the s-wave contribution is dominant near zero energy, the d-wave contribution is not negligible.