Nuclear spin alignment and static moments of light projectile fragments measured with the Level Mixing Resonance (LMR) method

We report on the first Level Mixing Resonance experiments performed on beta-decaying nuclei produced and aligned in intermediate energy fragmentation reactions. From the resonant change of the beta-asymmetry as a function of a static magnetic field, we derived information on the initial alignment of B-12 and N-18 projectile fragments and on the nuclear structure of the neutron N-18 nucleus. Positive alignments ranging from 0.9% to 14.4% have been found for different cuts in the longitudinal momentum distribution of B-12 and N-18 fragments, A very large ratio for the quadrupole frequency to the magnetic moment has been measured for the neutron rich N-18 fragments.