We found strong evidence for the existence of supersymmetry by studying the odd-odd nucleus 196 Au using the 197 Au͑ d, t͒, 197 Au͑p, d͒, and 198 Hg͑ d, a͒ transfer reactions. High resolution 196 Pt͑ p, d͒ and 196 Pt͑ d, t͒ transfer experiments performed in parallel yielded an improved level scheme of 195 Pt. Using extended supersymmetry, a single fit of the six parameter eigenvalue expression yielded a complete description of all observed low-lying excited states in the four nuclei forming the supermultiplet. The detailed comparison of the transfer amplitudes the odd-odd member of the supermultiplet 196 Au using a semimicroscopic transfer operator provides, then, evidence that this description is correct.

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Excited states in 196 Au, populated in the 196 Pt(p,n) and (d,2n) reactions, were investigated by in-beam ␥-ray and conversion-electron spectroscopy. Two only weakly connected level structures, built on the 2 Ϫ ground state ͑negative-parity level scheme͒ and on the 5 ϩ isomer at 84.7 keV ͑positive-parity level scheme͒, are observed. The point of main effort of the present work was the investigation of the negative-parity level scheme in connection with its description within the framework of an extended supersymmetry. For this level scheme we observe 25 excited states up to an excitation energy of 500 keV, of which 23 had already been identified in a recent study of 196 Au by transfer reactions. From 500 to 800 keV we observe 28 additional levels compared to 20 levels observed in the transfer reactions. The excitation energies derived in the studies of the (p,n) compound reaction and the (p,d) transfer reaction agree within 1 keV, and the complementary information obtained from the two reactions led to improved spin determinations. The negative-parity level structure is compared with the predictions of the extended supersymmetry.

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Excited states in 180 Ta, populated in the 180 Hf(p,n) and (d,2n) reactions, were investigated by in-beam ␥-ray and conversion-electron spectroscopy. In addition to the excited two-quasiparticle bands with K ϭ0 Ϫ and 1 Ϫ known from previous work, we have identified six other low-lying two-quasiparticle bands with K р4. At intermediate K, 12 previously unkown levels were identified that could, however, not be associated reliably with rotational bands. These levels might be of significance in connection with the as yet unresolved problem of the stellar production mechanism for the 9 Ϫ isomer of 180 Ta. At higher K we observe only levels known from the previous in-beam ␥-spectroscopic studies with heavier projectiles, but suggest for some levels a different ordering into rotational bands based on band-mixing considerations. We also report a deuteron spectrum measured in the 181 Ta( p,d) 180 Ta reaction with high resolution and statistics. This spectrum served for configuration assignments and yields an energy of 78Ϯ1 keV for the 9 Ϫ isomer in 180 Ta.