Levels of Yb174 populated in average resonance neutron capture

The primary γ rays and energy levels in Yb174 were investigated in average resonance neutron capture using tailored neutron beams at 2 and 24 keV and a pair spectrometer at the High Flux Reactor at Brookhaven. A thermal neutron beam was also used. Nearly 300 levels with spin up to J=4 are reported below 4 MeV. The distribution of radiative strength in this nucleus was derived and is analyzed with a giant dipole resonance and single-particle strength models. The neutron binding energy in Yb174 was determined at 7464.4(3)keV.