LOW-LYING DIPOLE EXCITATIONS OF THE TI-48 NUCLEUS - INVESTIGATION BY THE METHOD OF RESONANCE FLUORESCENCE

A nuclear-resonance-fluorescence experiment with Ti-48 nuclei exposed to bremsstrahlung that has an endpoint energy of 6.6 MeV and which is generated by a continuous-wave electron beam of the injector of a race -track microtron is described. Excitation of five spin-1 levels is obs erved. The widths of these levels with respect to decay to the ground state and the reduced probabilities of gamma transitions are determine d. In the energy region below 6.5 MeV, the total reduced probability o f M1 transitions is found to be 1.06 +/- 0.08 mu(N)(2). The M1 transit ions in the Ti-48 nucleus are interpreted as a manifestation of the or bital-type magnetic dipole excitations that are peculiar to deformed n uclei. The structure of the M1 spectrum of Ti-48 indicates that this n ucleus is an axially asymmetric rotor whose quadrupole-deformation and nonaxiality parameters are delta = 0.26 +/- 0.04 and gamma = 19 degre es +/- 2 degrees, respectively.