Low-energy tail of the giant dipole resonance in 98Mo and 100Mo deduced from photon-scattering experiments


Low-energy tail of the giant dipole resonance in 98Mo and 100Mo deduced from photon-scattering experiments

Rusev, G.; Schwengner, R.; Dönau, F.; Erhard, M.; Grosse, E.; Junghans, A. R.; Kosev, K.; Schilling, K. D.; Wagner, A.; Becvar, F.; Krticka, M.

Dipole-strength distributions in the nuclides 98Mo and 100Mo up to the neutron-separation energies have been studied in photon-scattering experiments at the superconducting electron accelerator ELBE of the Forschungszentrum Dresden-Rossendorf. In order to determine the dipole-strength distribution up to the neutron emission threshold statistical methods were developed for the analysis of the measured spectra. The measured spectra of scattered photons were corrected for detector response and atomic background by simulations using the code GEANT3. Simulations of gamma-ray cascades were performed in order to correct the intensities of ground-state transitions for feeding from high-lying levels and to determine their branching ratios. The photoabsorption cross sections obtained for 98Mo and 100Mo from the present (gamma,gamma) experiments are combined with (gamma,n) data from literature resulting in a photoabsorption cross section covering the full range from 4 to about 15 MeV of interest for nuclear astrophysics network calculations. Novel information about the low-energy tail of the Giant Dipole Resonance and the energy spreading of its strength is derived. The photoabsorption cross sections deduced from the present photon-scattering experiments are compared with existing data from neutron capture and 3He induced reactions.

Keywords: Photon scattering; nuclear structure; giant dipole resonance; dipole strength; photoabsorption cross section

Permalink: https://www.hzdr.de/publications/Publ-9885
Publ.-Id: 9885