Abstract:
The 100% polarized photon beam at the high
intensity gamma ray source (HIgammaS) at Duke
University has been used to determine the
parity of six dipole excitations between 2.9
and 3.6 MeV in the deformed nuclei 172,174Yb
in photon scattering (gamma-->,gamma')
experiments. The measured parities are
compared with previous assignments based on
the K quantum number that had been assigned
in nuclear resonance fluorescence (NRF)
experiments by using the Alaga rules. A
systematic survey of the relation between
gamma-decay branching ratios and parity
quantum numbers is given for the rare earth
nuclei.