Evolution of the giant dipole resonance in excited 120Sn and 208Pb nuclei populated by inelastic alpha scattering

Compilation of giant electric dipole resonances built on excited states

“…The Reisdorf approach builds on the generalized superfluid model by Ignatyuk et al [42], but it uses a global parameterization for the asymptotic level density parameter a. In one case [30], the level-density model by Fineman et al [43] is used in the data analysis.…”

“…These γ rays can either be modeled (and hence subtracted from the high-energy γ spectrum which is to be fitted by the statistical-model calculation as in [30]), or they are simply considered as a source of systematic error as in [51]. Another possible source of high-energy γ rays is the pre-equilibrium γ emission during the formation of the compound nucleus which has been investigated by measuring high-energy γ spectra for (isospin) symmetric and asymmetric reactions as in, e.g., [53; 54; 55].…”

Multipole excitations in hot nuclei within the finite temperature quasiparticle random phase approximation framework

“…Experimentally, several groups tried to study the temperature dependence of the mean energy and width of the giant resonances. In recent decades, giant dipole resonances built on excited states have been studied either using inelastic scattering of light particles or fusion-evaporation reactions [15][16][17][18][19]. Results revealed that, while the GDR energy remains almost constant, this is not the case for the width, which changes both as a function of excitation energy and spin.…”

Damping of Giant Dipole Resonance in Highly Excited Nuclei

“…The GDR built on the ground state of heavy nuclei has a small width (∼ 4 -5 MeV) and the integrated cross section up to around 30 MeV that exhausts the Thomas-Reich-Kuhn (TRK) sum rule. The GDR built on highly excited compound (CN) nuclei was observed for the first time in 1981 [1], and at present a wealth of experimental data has been accumulated for the GDR widths at finite temperature T and angular momentum J in various medium and heavy nuclei formed in heavy ion fusions [2], deep inelastic scattering of light particles on heavy targets [3,4], and α induced fusions [5]. The common features of the hot GDR are: (1) Its energy is nearly independent of T and J, (2) Its full width at half maximum (FWHM) remains mostly unchanged in the region of T ≤ 1 MeV, but increases sharply with T within 1≤ T ≤ 2.5 -3 MeV, and seems to saturate at T ≥ 4 MeV.…”