M1 strength and (e, e′) form factors of 46,48Ti within the RPA

Abstract

The abundant experimental information on low- and high-energy M1 excitations in 46,48Ti, obtained recently through (e, e′), (p, p′) and (γ, γ′) experiments, is well described within a quasiparticle RPA approach, based on a deformed Woods-Saxon potential plus spin-spin and quadrupole-quadrupole interactions. It includes a procedure which restores the rotational invariance of the hamiltonian. The low-lying strong M1 states overlap up to 36% with the scissors state of the two-rotor model. These states, as well as some medium-energy 1+ excitations, represent a weakly collective scissors motion, more pronounced in 46Ti than in 48Ti. The titanium isotopes offer a better approximation to the scissors state than do the heavy nuclei because in lighter nuclei the scissors state is less collective.