Giant dipole resonance built on hot rotating nuclei produced during evaporation of light particles from the<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mmultiscripts><mml:mi mathvariant="normal">Mo</mml:mi><mml:mprescripts/><mml:none/><mml:mrow><mml:mn>88</mml:mn></mml:mrow></mml:mmultiscripts></mml:math>compound nucleus

High-energy giant dipole resonance (GDR) $\ensuremath{\gamma}$ rays were measured following the decay of the hot, rotating compound nucleus of $^{88}\mathrm{Mo}$, produced at excitation energies of 124 and 261 MeV. The reaction $^{48}\mathrm{Ti}$ + $^{40}\mathrm{Ca}$ at 300 and 600 MeV bombarding energies has been used. The data were analyzed using the statistical model Monte Carlo code gemini++. It allowed extracting the giant dipole resonance parameters by fitting the high-energy $\ensuremath{\gamma}$-ray spectra. The extracted GDR widths were compared with the available data at lower excitation energy and with theoretical predictions based on (i) The Lublin-Strasbourg drop macroscopic model, supplemented with thermal shape fluctuations analysis, and (ii) The phonon damping model. The theoretical predictions were convoluted with the population matrices of evaporated nuclei from the statistical model gemini++. Also a comparison with the results of a phenomenological expression based on the existing systematics, mainly for lower temperature data, is presented and discussed. A possible onset of a saturation of the GDR width was observed around $T=3$ MeV.

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