Parity assignments in 172,174Yb using polarized photons and the K quantum number in rare earth nuclei

Abstract

The 100% polarized photon beam at the high intensity γ ray source (HIγS) 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 (γ →, γ′) 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 γ-decay branching ratios and parity quantum numbers is given for the rare earth nuclei. © 2005 The American Physical Society.