We study nuclear multipole resonances in the framework of the random-phase approximation by using the chiral potential ${\mathrm{NNLO}}_{\text{sat}}$. This potential includes two- and three-body terms that have been simultaneously optimized to low-energy nucleon-nucleon scattering data and selected nuclear structure data. Our main focuses have been the isoscalar monopole, isovector dipole, and isoscalar quadrupole resonances of the closed-shell nuclei, ${}^4\mathrm{He}$, ${}^{16,22,24}\mathrm{O}$, and ${}^{40,48}\mathrm{Ca}$. These resonance modes have been widely observed in experiment. In addition, we use a renormalized chiral potential $V_{\text{low-}k}$, based on the ${\mathrm{N}}^3\mathrm{LO}$ two-body potential by Entem and Machleidt [Phys. Rev. C 68, 041001 (2011)]. This introduces a dependency on the cutoff parameter used in the normalization procedure as reported in previous works by other groups. While ${\mathrm{NNLO}}_{\text{sat}}$ can reasonably reproduce observed multipole resonances, it is not possible to find a single cutoff parameter for the $V_{\text{low-}k}$ potential that simultaneously describes 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 ${}^{22,24}\mathrm{O}$ show a mixing nature of isoscalar and isovector resonances in the dipole channel at low energies. We predict that ${}^{22}\mathrm{O}$ and ${}^{24}\mathrm{O}$ have low-energy isoscalar quadrupole resonances at energies lower than 5 MeV.

• Received 11 January 2018

DOI:https://doi.org/10.1103/PhysRevC.97.054306