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The \ensuremath{\gamma} cascades feeding into low-K and high-K bands in ${}^{163}$Er are investigated analyzing variances and covariance of the spectrum fluctuations. From a large data set of 1${0}^{9}$ triple coincidences, \ensuremath{\gamma}-\ensuremath{\gamma} coincidence spectra gated by resolved low-lying rotational bands are analyzed. Low-K bands are found to be fed by a much larger effective number of cascades than high-K bands. The covariance between pairs of gated spectra shows that the cascades feeding low-K bands are different from those feeding the high-K bands. The persistence of the K-selection rules for the excited rotational bands within the angular momentum region $30\ensuremath{\Elzxh}\ensuremath{\le}I\ensuremath{\le}40\ensuremath{\Elzxh}$ is suggested as explanation.

The strength function and the angular distribution of the high energy {gamma} rays emitted by the giant dipole resonance (GDR) in hot rotating{sup 109,110}Sn nuclei have been measured at temperature {ital T}=1.8 MeV and at four values of the angular momentum {ital I}. The GDR width is {approx}2 times larger than at {ital T}=0 and increases by {approx}20% as {ital I} goes from 40 to 54{h_bar}. The {ital a}{sub 2}({ital E}{sub {gamma}}) increases by a factor of {approx}2. Based on these two facts and on the comparison with theory we conclude that large deformations driven by {ital I} and combined with shape and orientation fluctuations are responsible for the measured increases. Collisional damping is constant and practically equal to the {ital T}=0 case.