Abstract
Magnetic dipole () excitations constitute not only a fundamental mode of nucleonic transitions, but they are also relevant for nuclear astrophysics applications. We have established a theory framework for the description of transitions based on the relativistic nuclear energy density functional. For this purpose, the relativistic quasiparticle random phase approximation (RQRPA) is established using density-dependent point coupling interaction DD-PC1, supplemented with the isovector-pseudovector interaction channel in order to study unnatural parity transitions. The introduced framework has been validated using the sum rule for core-plus-two-nucleon systems, and employed in studies of the spin, orbital, isoscalar, and isovector transition strengths that relate to the electromagnetic probe in magic nuclei and and open shell nuclei and . In these systems, the isovector spin-flip transition is dominant, mainly between one or two spin-orbit partner states. It is shown that pairing correlations have a significant impact on the centroid energy and major peak position of the mode. The excitations could provide an additional constraint to improve nuclear energy density functionals in the future studies.
- Received 4 March 2020
- Revised 22 April 2020
- Accepted 23 September 2020
DOI:https://doi.org/10.1103/PhysRevC.102.044315
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