The charge-exchange spin-dipole (SD) excitations for both $(p,n)$ and $(n,p)$ channels in ${}^{16}$O are investigated in the fully self-consistent random phase approximation based on the covariant density functional theory. The fine structure of SD excitations in the most up-to-date ${}^{16}$O($\vec{p},\vec{n}$)${}^{16}$F experiment is excellently reproduced without any readjustment in the functional. The SD excitations are characterized by the delicate balance between the $\sigma$- and $\omega$-meson fields via the exchange terms. The fine structure of SD excitations for the ${}^{16}$O($n,p$)${}^{16}$N channel is predicted for future experiments.

• Received 29 December 2011

DOI:https://doi.org/10.1103/PhysRevC.85.064302