1.
Phys Rev Lett
; 88(1): 012502, 2002 Jan 07.
Article
in English
| MEDLINE
| ID: mdl-11800940
ABSTRACT
The quality and intensity of gamma rays at the High Intensity gamma-ray Source are shown to make nuclear resonance fluorescence studies possible at a new level of precision and efficiency. First experiments have been carried out using an intense (10(7) gamma/s) beam of 100% linearly polarized, nearly monoenergetic, gamma rays on the semimagic nucleus (138)Ba. Negative parity quantum numbers have been assigned to 18 dipole excitations of (138)Ba between 5.5 MeV and 6.5 MeV from azimuthal gamma-intensity asymmetries.