Effects of thermal shape fluctuations and pairing fluctuations on the giant dipole resonance in warm nuclei

Abstract

Apart from the higher limits of isospin and temperature, the properties of atomic nuclei are intriguing and less explored at the limits of lowest but finite temperatures. At very low temperatures there is a strong interplay between the shell (quantal fluctuations), statistical (thermal fluctuations), and residual pairing effects as evidenced from the studies on giant dipole resonance (GDR). In our recent work [Phys. Rev. C \textbf{90}, 044308 (2014)], we have outlined some of our results from a theoretical approach for such warm nuclei where all these effects are incorporated along within the thermal shape fluctuation model (TSFM) extended to include the fluctuations in the pairing field. In this article, we present the complete formalism based on the microscopic-macroscopic approach for determining the deformation energies and a macroscopic approach which links the deformation to GDR observables. We discuss our results for the nuclei ${}^{97}$Tc, ${}^{120}$Sn, ${}^{179}$Au, and ${}^{208}$Pb, and corroborate with the experimental data available. The TSFM could explain the data successfully at low temperature only with a proper treatment of pairing and its fluctuations. More measurements with better precision could yield rich information about several phase transitions that can happen in warm nuclei.

arXiv comment35 pages, 12 figures, Accepted for publication in Physical Review C

References in corpus (21)

• Nuclear Ground-State Masses and Deformations
• Isospin Character of the Pygmy Dipole Resonance in 124Sn
• Giant Dipole Resonance as a Fingerprint of $\alpha$ Clustering Configurations in ${}^{12}$C and ${}^{16}$O
• Isoscalar giant resonances in the Sn nuclei and implications for the asymmetry term in the nuclear-matter incompressibility
• Scaling Properties of the Giant Dipole Resonance Width in Hot Rotating nuclei
• First principles description of the giant dipole resonance in 16O
• Behavior of the giant-dipole resonance in ${}^{120}$Sn and ${}^{208}$Pb at high excitation energ
• Critical behavior in the variation of GDR width at low temperature
• Self-consistent calculations of the electric giant dipole resonances in light and heavy mass nuclei
• Modified Hartree-Fock-Bogoliubov at finite temperature
• Pairing effect on the giant dipole resonance width at low temperature
• Probing the critical behavior in the evolution of GDR width at very low temperatures in A~100 mass region
• Measurement of Giant Dipole Resonance width at low temperature: A new experimental perspective
• Pairing in hot rotating nuclei
• Pairing reentrance in hot rotating nuclei
• Giant dipole resonance width as a probe for nuclear deformation at finite excitation
• Giant dipole resonance with exact treatment of thermal fluctuations
• Pairing Reentrance Phenomenon in Heated Rotating Nuclei in the Shell Model Monte Carlo Approach
• Giant dipole resonance in ${}^{201}$Tl at low temperature
• Pairing effect in thermal shape fluctuation model on the width of giant dipole resonance
• Applicability of shape parameterizations for giant dipole resonance in warm and rapidly rotating nuclei

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• Giant Dipole Resonance studies in Ba isotopes at $\text{ E/A}\sim$ 5 MeV