M1 RESONANCES IN UNSTABLE MAGIC NUCLEI

Within a microscopic approach which takes into account RPA configurations, the single-particle continuum and more complex 1 p 1 h x phonon configurations isoscalar and isovector Mt excitations for the unstable nuclei Ni-56, Ni-78 and Sn-100, Sn-132 are calculated. For comparison, the experimentally known M1 excitations in Ca-40 and Pb-208 have also been calculated. In the latter nuclei good agreement in the centroid energy, the total transition strength and the resonance width is obtained. With the same parameters we predict the magnetic excitations for the unstable nuclei. The strength is sufficiently concentrated to be measurable in radioactive beam experiments. New features are found for the very neutron rich nucleus 78Ni and the neutron deficient nucleus 100Sn.