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Gamma-ray transition-energy spectra up to E y -33 MeV have been measured for the decay of the compound nucleus m Sn* populated at excitation energies up to £*^100 MeV. Above E y -20 MeV an excess of gamma rays over the contribution from the isovector giant dipole resonance is observed in the energy range where the isovectors giant quadrupole resonance built on excited states is expected. The width of the giant dipole resonance in 108 -ni Sn* shows a large increase with increasing nuclear temperature and angular momentum.

We have made the first clear measurements of rotational damping widths in nuclei. In a mixture of three Yb nuclei, these widths are 300 +/- 60 keV between 1.2 and 1.5 MeV gamma-ray energy [approximately (37-57)Planck's constant]. Compound damping and motional narrowing are discussed in connection with these results.

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