Speaker
Description
The relativistic nuclear field theory (RNFT) developed throughout the last decade will be featured as an approach to the nuclear many-body problem, which is based on meson-nucleon Lagrangian and connects consistently the high-energy scale of heavy mesons, the medium-energy range of the pion, and the low-energy domain of emergent collective vibrations (phonons). Mesons and phonons build up the effective interaction in various channels, in particular, the phonon-exchange part takes care of the retardation effects, which are of great importance for the fragmentation of single-particle states, spreading of collective giant resonances and soft modes, quenching and beta-decay rates with significant consequences for astrophysics and theory of weak processes in nuclei.
Recent progress on the response theory in the proton-neutron channel has allowed for a very good description of spin-isospin-flip excitations. Spectra of such excitations can serve for probing the nucleon-nucleon interaction in the isovector sector caused by the exchange of pion and rho-meson between nucleons in the strongly-correlated medium. At the same time, such excitations as, for instance, Gamow-Teller and spin-dipole resonances in medium-mass nuclei are of a high astrophysical importance as they are in the direct relation to beta-decay and electron capture rates. Some more exotic isospin-flip excitations studied lately at NSCL facility have been also described very reasonably by the RNFT. Recent developments consider excitation modes in the deuteron transfer channel in view of their role in mediating the proton-neutron pairing and in constraining the delta-meson contribution to the nuclear forces.
