Finite-temperature linear response theory based on relativistic Hartree Bogoliubov model with point-coupling interaction

The finite-temperature linear response theory based on the relativistic Hartree-Bogoliubov (FT-RHB) model is developed in charge-exchange channel to study temperature evolution of spin-isospin excitations. Calculations are performed self-consistently with point-coupling interactions DD-PC1 and DD-PCX. In channel, pairing interaction can be split into isovector ($T = 1$) isoscalar 0$) parts. For component, same separable form Gogny D1S used both for ground-state calculation as well residual interaction, while strength determined by comparison experimental data Gamow-Teller resonance (GTR) Isobaric analog (IAR) centroid energy differences even-even tin isotopes. effects introduced treating Bogoliubov quasiparticles within a grand-canonical ensemble. Thus, unlike conventional formulation quasiparticle random-phase approximation (QRPA) Bardeen-Cooper-Schrieffer (BCS) basis, our formulated Hartree-Fock-Bogoliubov (HFB) basis. Implementing force allows reduction complicated two-body matrix elements, which considerably decreases dimension problem coordinate space. main advantage this method avoid diagonalization large QRPA matrix, especially at finite where size configuration space significantly increased. implementation code IAR, GTR, spin-dipole (SDR) isotopes range $T 0 - 1.5$ MeV.