Smooth crossings between the N = 4 and N = 6 orbits and adiabatic configuration changes at high angular momentum in

Rotational structures in 134Nd have been investigated using the GASP array via the 110Pd(28Si,4n) reaction at 130 MeV. Each of the observed high-spin bands experiences a change in structure, that involves the promotion of a particle from the N = 4 into the N = 6 orbital. The adiabatic character of the corresponding bandcrossings, indicated by vertical or gradual upbendings of the aligned angular momentum, gives evidence of a sizeable mixing between the N = 4 and N = 6 configurations. The successive occupation of the first and second N = 6 intruder orbitals indicates that, at difference from the paired alignment exhibited by normal-deformed nuclei between the ground-state band and the S-band, in highly-deformed nuclei, the unpaired alignment is the favored mechanism for generating high angular momenta.