Giant dipole resonance and shape transitions in hot and rotating Mo88

The giant dipole resonance (GDR) observables are calculated within the thermal shape fluctuation model by considering the probability distributions of different angular momentum ($I$) and temperature ($T$) values estimated recently in the deexcitation process of the compound nucleus $^{88}\mathrm{Mo}$. These results are found to be very similar to the results obtained with the average $T$ (${T}_{\mathrm{ave}}$) and average $I$ (${I}_{\mathrm{ave}}$) corresponding to those distributions. The shape transitions in $^{88}\mathrm{Mo}$ at different $T$ and $I$ are also studied through the free energy surfaces calculated within the microscopic-macroscopic approach. The deformation of $^{88}\mathrm{Mo}$ is found to increase considerably with $T$ and $I$, leading to the Jacobi shape transition at $I\ensuremath{\sim}50\phantom{\rule{0.28em}{0ex}}\ensuremath{\hbar}$. The combined effect of increasing deformation, larger fluctuations at higher $T$, and larger Coriolis splitting of GDR components at higher $I$, leads to a rapid increase in the GDR width.