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 frag mentation 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 nuc lear structure of the neutron N-18 nucleus. Positive alignments rangin g from 0.9% to 14.4% have been found for different cuts in the longitu dinal momentum distribution of B-12 and N-18 fragments, A very large r atio for the quadrupole frequency to the magnetic moment has been meas ured for the neutron rich N-18 fragments.