g factors of high spin states in /sup 154,155/Er and /sup 157/Yb and the nature of the neutron (13/2)/sup +/ quasiparticle in transitional nuclei

The g factors of the I/sup ..pi../ = 11/sup -/ isomer in /sup 154/Er and I/sup ..pi../ = (13/2)/sup +/ isomers in /sup 155/Er and /sup 157/Yb were measured using the technique of time-dependent perturbed angular distributions. The value obtained for /sup 154/Er, g = +0.0154(12), indicates a predominant configuration of ..nu..(i/sub 13/2/,h/sub 9/2/)/sub 10//sup -/, 11/sup -/ for the isomeric state. The results for /sup 155/Er and /sup 157/Yb, g = -0.085(5) and g = -0.116(12), respectively, are explained in terms of Pauli blocking of the 3/sup -/ core excitation component in the wave function of the (13/2)/sup +/ state.