Reduced sensitivity of the $(d, p)$ cross sections to the deuteron model beyond adiabatic approximation

TL;DR

This study develops a non-adiabatic model for (d, p) reactions with nonlocal potentials, showing reduced sensitivity to n-p interactions and emphasizing the importance of beyond-adiabatic analysis for accurate spectroscopic studies.

Contribution

The paper introduces a leading-order non-adiabatic model accounting for nonlocality, reducing sensitivity to n-p potential variations in (d, p) cross sections.

Findings

Reduced sensitivity to high n-p momenta in non-adiabatic model

Stronger non-adiabatic effects with nonlocal potentials

Supports extending analysis beyond adiabatic approximation

Abstract

It has recently been reported [Phys. Rev. Lett. 117, 162502 (2016)] that (d, p) cross sections can be very sensitive to the n-p interactions used in the adiabatic treatment of deuteron breakup with nonlocal nucleon-target optical potentials. To understand to what extent this sensitivity could originate in the inaccuracy of the adiabatic approximation we have developed a leading-order local- equivalent continuum-discretized coupled-channel model that accounts for non-adiabatic effects in the presence of nonlocality of nucleon optical potentials. We have applied our model to the astro- physically relevant reaction $^{26m}$Al$(d, p) ^{27}$Al using two different n-p potentials associated with the lowest and the highest n-p kinetic energy in the short-range region of their interaction, respectively. Our calculations reveal a significant reduction of the sensitivity to the high n-p momenta thus confirming that it is mostly associated with theoretical uncertainties of the adiabatic approximation itself. The non-adiabatic effects in the presence of nonlocality were found to be stronger than those in the case of the local optical potentials. These results argue for extending the analysis of the $(d, p)$ reactions, measured for spectroscopic studies, beyond the adiabatic approximation.