Study of collective dipole excitations below the giant dipole resonance at HIγS

Journal Article (Journal Article)

The High-Intensity Gamma-ray Source utilizing intra-cavity back-scattering of free electron laser photons from relativistic electrons allows one to produce a unique beam of high-flux gamma rays with 100% polarization and selectable energy and energy resolution which is ideal for low-energy γ-ray scattering experiments. Nuclear resonance fluorescence experiments have been performed on N=82 nuclei. High sensitivity studies of E1 and M1 excitations at energies close to the neutron emission threshold have been performed. The method allows the determination of excitation energies, spin, parities, and decay branching ratios of the pygmy dipole mode of excitation. The observations are compared with calculations using statistical and quasi-particle random-phase approximations. © 2007 American Institute of Physics.

Full Text

Duke Authors

Cited Authors

  • Tonchev, AP; Angell, C; Boswell, M; Chyzh, A; Howell, CR; Karwowski, HJ; Kelley, JH; Tornow, W; Tsoneva, N; Wu, YK

Published Date

  • April 4, 2007

Published In

Volume / Issue

  • 891 /

Start / End Page

  • 339 - 347

Electronic International Standard Serial Number (EISSN)

  • 1551-7616

International Standard Serial Number (ISSN)

  • 0094-243X

Digital Object Identifier (DOI)

  • 10.1063/1.2713535

Citation Source

  • Scopus