Angular momentum gated giant dipole resonance measurements in the reaction28Si+58NiatE(28Si)=100and 125 MeV

High-energy $\ensuremath{\gamma}$ rays in the energy range of $\ensuremath{\sim}4\char21{}35\mathrm{MeV}$ were measured in coincidence with a $\ensuremath{\gamma}$-ray multiplicity detector array in the reaction ${}^{28}\mathrm{Si}{+}^{58}\mathrm{Ni}$ at ${E(}^{28}\mathrm{Si})=100$ and 125 MeV. The data were analyzed using the statistical model, and the giant dipole resonance parameters were extracted for various multiplicity windows. The exclusive temperature dependence of the $\ensuremath{\gamma}$-ray strength function has been obtained for a wide range of angular momentum, while the angular momentum dependence has been derived over a restricted range of temperature. The observed increase in the resonance width can be attributed to an increase in temperature. No dependence on angular momentum is observed. The last observation is at variance with the results in the tin region for similar rotational frequencies.