Spin and orbital contributions to collective M1 transitions in 46,48Ti

Low- and high-lying Kπ=1+ states and M1 transitions in 46,48Ti are studied. The model hamiltonian is treated in the quasi-particle random phase approximation (QRPA) with an exact restoration of its rotational invariance. A considerable spin contribution to the transition matrix elements is found for the low-energy (about 4 MeV) strong M1 transition (the orbital contribution being 30-70% of the spin one), although the microscopic structure of this state in 46Ti is typical for an orbital isovector excitation. The calculated energies and B(M1) values are in a good agreement with the experimental data. The results are compared to the estimates of the isovector scissor model. (orig.)