Spin-Dependent Nucleon-Nucleus Interactions Constrained by Neutron Observables and Their Impact on Near-Barrier Proton Fusion

@misc{heo2026spindependent,
  title = {{Spin-Dependent Nucleon-Nucleus Interactions Constrained by Neutron Observables and Their Impact on Near-Barrier Proton Fusion}},
  author = {Kyoungsu Heo and Myung-Ki Cheoun and Kouichi Hagino},
  howpublished = {arXiv},
  year = {2026},
  month = oct,
  doi = {10.48550/arxiv.2605.26561},
  eprint = {2605.26561},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2605.26561},
}

TY  - UNPB
TI  - Spin-Dependent Nucleon-Nucleus Interactions Constrained by Neutron Observables and Their Impact on Near-Barrier Proton Fusion
AU  - Kyoungsu Heo
AU  - Myung-Ki Cheoun
AU  - Kouichi Hagino
PY  - 2026
DA  - 2026/10/26
PB  - arXiv
DO  - 10.48550/arxiv.2605.26561
UR  - https://arxiv.org/abs/2605.26561
AB  - We investigate the role of spin-dependent nucleon--nucleus interactions in nuclear reactions. To this end, we use neutron spin observables to constrain the dominant central spin-spin form factors and then apply the corresponding like-channel interactions to near-barrier fusion in the p+^93Nb system. The interactions are constructed within a folding framework based on a finite-range effective nucleon-nucleon force and organized in terms of radial form factors associated with their spin-spin, tensor, and spin-orbit components. Neutron spin observables in the n + ^27Al, ^59Co, and ^93Nb target systems are analyzed within a distorted-wave Born approximation (DWBA) framework {to examine the sign and scale of the central spin-spin contribution and the assembled operator conventions.} The calculation reproduces the observed sign systematics of the neutron spin observables for the three targets, consistent with the dominant central spin-spin contribution in the adopted model. The unlike-channel (neutron--proton) interaction constrained by neutron scattering is then reconstructed for the corresponding like-channel (proton--proton) interaction and applied to a coupled-channels description of near-barrier fusion for the p+^93Nb system. The retained real spin-dependent interactions lead only to a weak modification of the effective barrier and a very small change in the unpolarized fusion cross section within the present model. The present work thus connects the neutron-scattering constraints on the operator conventions with the fusion calculation in the proton channel, and estimates the scale of the corresponding real spin-dependent correction in near-barrier fusion.
ER  -