Abstract
Exclusive measurements of high-energy rays have been performed in and at the same excitation energy to study the properties of the giant dipole resonance (GDR) over a wide range. The high-energy rays are measured in coincidence with the multiplicity of low-energy rays to disentangle the effect of temperature and angular momentum . The GDR parameters are extracted employing a simulated Monte Carlo statistical model analysis. The observed -ray spectra of can be explained with prolate deformation, whereas a single-component Lorentzian function which corresponds to a spherical shape could explain the -ray spectra of . The observed GDR width in is narrower compared to that of . The statistical model best-fit GDR cross sections are found to be in reasonable agreement with the thermal shape fluctuation model (TSFM) calculations. Further, it is shown that the variation of GDR width with is well reproduced by the TSFM calculations over the temperature range of 1.1–1.7 MeV.
- Received 15 April 2017
DOI:https://doi.org/10.1103/PhysRevC.96.014309
©2017 American Physical Society