Chiral NNLO$_{\text{sat}}$ descriptions of nuclear multipole resonances within the random phase approximation
Abstract
We study nuclear multipole resonances in the framework of the random phase approximation using the chiral potential NNLO. This potential includes two- and three-body terms that has been simultaneously optimized to low-energy nucleon-nucleon scattering data and selected nuclear structure data. Our main foci have been the isoscalar monopole, isovector dipole, and isoscalar quadrupole resonances of the closed-shell nuclei, He, O, and Ca. These resonance modes have been widely observed in experiment. In addition, we use a renormalized chiral potential , based on the NLO two-body potential by Entem and Machleidt [Phys. Rev. \textbf{C68}, 041001 (2011)]. This introduces a dependency on the cutoff parameter used in the normalization procedure as reported in previous works by other groups. While NNLO can reasonably reproduce observed multipole resonances, it is not possible to find a single cutoff parameter for the potential that simultaneously describe the different types of resonance modes. The sensitivity to the cutoff parameter can be explained by missing induced three-body forces in the calculations. Our results for neutron-rich O show a mixing nature of isoscalar and isovector resonances in the dipole channel at low energies. We predict that O and O have low-energy isoscalar quadrupole resonances at energies lower than 5 MeV.
Keywords
Cite
@article{arxiv.1801.04454,
title = {Chiral NNLO$_{\text{sat}}$ descriptions of nuclear multipole resonances within the random phase approximation},
author = {Q. Wu and B. S. Hu and F. R. Xu and Y. Z. Ma and S. J. Dai and Z. H. Sun and G. R. Jansen},
journal= {arXiv preprint arXiv:1801.04454},
year = {2018}
}
Comments
25 pages, 8 figures