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arXiv · 1905.13071

Effects of an induced three-body force in the incident channel of (d,p) reactions

M. J. Dinmore·N. K. Timofeyuk·J. S. Al-Khalili·R. C. Johnson
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Abstract

A widely accepted practice for treating deuteron breakup in $A(d,p)B$ reactions relies on solving a three-body $A+n+p$ Schrödinger equation with pairwise $A$-$n$, $A$-$p$ and $n$-$p$ interactions. However, it was shown in [Phys. Rev. C \textbf{89}, 024605 (2014)] that projection of the many-body $A+2$ wave function into the three-body $A+n+p$ channel results in a complicated three-body operator that cannot be reduced to a sum of pairwise potentials. It contains explicit contributions from terms that include interactions between the neutron and proton via excitation of the target $A$. Such terms are normally neglected. We estimate the first order contribution of these induced three-body terms and show that applying the adiabatic approximation to solving the $A+n+p$ model results in a simple modification of the two-body nucleon optical potentials. We illustrate the role of these terms for the case of $^{40}$Ca($d,p$)$^{41}$Ca transfer reactions at incident deuteron energies of 11.8, 20 and 56 MeV, using several parameterisations of nonlocal optical potentials.

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M. J. Dinmore, N. K. Timofeyuk, J. S. Al-Khalili, R. C. Johnson. 2019-05-30. Effects of an induced three-body force in the incident channel of (d,p) reactions. https://doi.org/10.1103/physrevc.99.064612

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