Magnetic moments of the first excited 2+ states in the semi-magic A=112,114,116,122,124 Sn isotopes

The g factors of the first excited 2+ states in the A=112,114,116,122,124 Sn isotopes have been measured with high accuracy using the transient field technique in combination with Coulomb excitation in inverse kinematics. The experimental results are discussed in a qualitative way on the basis of empirical single particle g factors of the relevant proton and neutron orbitals and compared to a number of different theoretical calculations. The results are found to be best described by shell-model calculations in an extended configuration space. Clear evidence for the contribution of neutron pair excitations from the 1d3/2 to the 0h11/2 orbital to the wave function of the 2+ state in 122,124Sn has been obtained.