Orbital and spin magnetic quadrupole response in heavy nuclei -: art. no. 054305

We compute the magnetic quadrupole strength function in heavy spherical and deformed nuclei in proton-neutron random-phase approximation using a separable Hamiltonian that couples magnetic and electric channels and adopting a technique that avoids the diagonalization of the eigenvalue matrix. We intend to check if the different sensitivity of the spin dipole and orbital responses to the multipole terms of the Hamiltonian leads to an energy separation of the two modes sufficient for the identification of the twist mode. We explore also the possibility of a K splitting induced by deformation, in analogy to the electric giant dipole resonance. also briefly studied for the sake of completeness.