Giant dipole resonance and shape transitions in warm and rapidly rotating nuclei
Institute of Physics, Sachivalaya Marg, 751 005, Bhubaneswar, India
2 Department of Physics, Sonepur College, 767017, Orissa, Subarnapur, India
Accepted: 31 May 2005
Published online: 26 August 2005
We discuss the shape transitions in few medium heavy-mass nuclei with emphasis on low-temperature behaviour of the giant dipole resonance (GDR) observables. We employ a macroscopic approach towards GDR in which the GDR observables are related to the nuclear shapes. Shape calculations were done using the cranked Nilsson-Strutinsky method (CNSM) extended to finite temperature. Thermal shape fluctuations are computed with free energies calculated employing Landau parameterization as well as those calculated exactly (without using parameterizations) at given spin and temperature. The results obtained are confronted with the experimental data wherever available. Our study reveals that if the fluctuations are treated properly, then, in spite of thermal fluctuations, GDR observables could very well reflect the shape transitions at low temperature.
PACS: 24.30.Cz Giant resonances – / 21.60.-n Nuclear structure models and methods – / 24.60.-k Statistical theory and fluctuations –
© Società Italiana di Fisica and Springer-Verlag, 2005