Charge-exchange isobaric resonances

Abstract

Three types of the charge-exchange isobaric resonances - giant Gamow-Teller (GTR), the analog (AR) and pygmy (PR) ones are investigated using the microscopic theory of finite Fermi systems and its approximated version. The calculated energies of GTR, AR and three PR’s are in good agreement with the experimental data. Calculated differences ΔEG-A=EGTR-EAR go to zero in heavier nuclei indicating the restoration of Wigner SU(4)-symmetry. The average deviation for ΔEG-A is 0.30 MeV for the 33 considered nuclei where experimental data are available. The comparison of calculations with experimental data on the energies of charge-exchange pygmy resonances gives the standard deviation δE<0:40 MeV. Strength functions for the 118Sn, 71Ga, 98Mo and 127I isotopes are calculated and the calculated resonance energies and amplitudes of the resonance peaks are close to the experimental values. Strong influence of the charge-exchange resonances on neutrino capturing cross sections is demonstrated.