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 separ able Hamiltonian that couples magnetic and electric channels and adopting a technique that avoids the diagonalization of the eigenvalue matrix. We int end to check if the different sensitivity of the spin dipole and orbital re sponses to the multipole terms of the Hamiltonian leads to an energy separa tion 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 t he sake of completeness.