THE NUCLEAR-STRUCTURE OF IR-194 STUDIED WITH THE IR-193(D,P) IR-194 REACTION

The nuclear structure of Ir-194 was investigated via the Ir-193(d,p) reaction using a 16 MeV deuteron beam. The reaction products were analyzed with a magnetic spectrograph and detected with photographic plates. The energy resolutions (FWHM) of the detected particles were typically congruent-to 8.9 keV. Spectra were recorded at 16 angles. The angular distributions of cross sections were fitted with theoretical curves from DWBA calculations, and the spectroscopic strengths were obtained. Level energies, parities, spectroscopic strengths and possible spin values were determined up to approximately 500 keV excitation energy. The experimental results were compared with the IBFFM and the Nilsson model. It was found that the IBFFM can approximately reproduce the structure of Ir-194, although there is a serious discrepancy with the level observed at 148.7 keV which has a large amount of l = 3 strength. Predictions with the Nilsson model, made for fixed oblate and prolate deformations, did not reproduce the spectroscopic strengths. When spin-parity information for more levels becomes available it may become feasible to improve the description by considering different deformation values, Coriolis mixing and the effects of the mixed target ground state, but at present an unambiguous set of assignments cannot be made.