Role of T=0 pairing in Gamow–Teller states in N=Z nuclei

Gamow–Teller (GT) states in N = Z nuclei with the mass number A from 48 to 64 are studied by using Hartree–Fock–Bogoliubov + quasi-particle random phase approximation ( HFB + QRPA ) with Skyrme interactions. The isoscalar spin-triplet ( T = 0 , S = 1 ) pairing interaction is taken into account in QRPA calculations. It is found in the context of SU(4) symmetry in the spin–isospin space that the GT strength of lower energy excitations is largely enhanced by the T = 0 pairing interaction which works cooperatively with the T = 1 pairing interaction in the ground state. A two-peaked structure observed recently in ( p , n ) reaction on 56Ni can be considered as a manifestation of the role of T = 0 pairing in the GT collective states.