Non-local interactions in the $(d,p)$ surrogate method for $(n,\gamma )$ reactions

Abstract

Single-neutron transfer reactions populating states in the continuum are interesting both for structure and astrophysics. In their description often global optical potentials are used for the nucleon-target interactions, and these interactions are typically local. In our work, we study the effects of nonlocality in $(d,p)$ reactions populating continuum states. This work is similar to that of [1] but now for transfer to the continuum. A theory for computing cross sections for inclusive processes $A(d,p)X$ was explored in [2]. Therein, local optical potentials were used to describe the nucleon-target effective interaction. The goal of the present work is to extend the theory developed in [2] to investigate the effects of including nonlocality in the effective interaction on the relevant reaction observables. We implement the R--matrix method to solve the non--local equations both for the nucleon wavefunctions and the propagator. We then apply the method to systematically study the inclusive process of $(d,p)$ on ${}^{16}$O, ${}^{40}$Ca, ${}^{48}$Ca and ${}^{208}$Pb at 10, 20 and 50 MeV. We compare the results obtained when non--local interactions are used with those obtained when local equivalent interactions are included. We find that nonlocality affects different pieces of the model in complex ways. Depending on the beam energy and the target, the non-elastic breakup can either increase or decrease. While the non-elastic transfer cross section for each final spin state can change considerably, the main prediction of the model [2], namely the shape of the spin distributions, remains largely unaltered by nonlocality. [1] L. J. Titus and F. M. Nunes. Testing the Perey effect. Phys. Rev. C, 89:034609, Mar 2014. [2] G. Potel, F. M. Nunes, and I. J. Thompson. Establishing a theory for deuteron-induced surrogate reactions. Phys. Rev. C, 92:034611, Sep 2015.

References in corpus (13)

• The impact of individual nuclear properties on $r$-process nucleosynthesis
• The R-matrix theory
• Reexamining closed-form formulae for inclusive breakup: Application to deuteron and ${}^6$Li induced reactions
• Optical potential from first principles
• Toward a complete theory for predicting inclusive deuteron breakup away from stability
• Forging the link between nuclear reactions and nuclear structure
• Numerical assessment of post-prior equivalence for inclusive breakup reactions
• Role of the Pauli principle in collective-model coupled-channels calculations
• Explicit inclusion of nonlocality in (d,p) transfer reactions
• Non-localities in nucleon-nucleus potentials
• Testing the Perey Effect
• Transfer reaction code with nonlocal interactions
• Energy dependence of non-local potentials

Cited by in corpus (7)

• Generalizing the calculable $R$-matrix theory and eigenvector continuation to the incoming wave boundary condition
• Prediction of (p,n) Charge-Exchange Reactions with Uncertainty Quantification
• Study of nonlocality effects in direct capture reactions with Lagrange-mesh $R$-matrix method
• Three-body problem with velocity-dependent optical potentials: a case of $(d,p)$ reactions
• Renormalization group evolution of optical potentials: explorations using a toy model
• Properties of a separable representation of optical potentials
• Considering non-locality in the optical potentials within eikonal models