Total neutron cross section measurements for 168Yb and 169Yb

Data on total neutron cross sections σsub(T) and resonance parameters of sup(168,169)Yb (Tsub(1/2) = 31 days) are presented. The measurements were carried out by the time-of-flight technique at a neurton spectrometer installed in the SM-2 reactor horizontal channel. Using thus measured neutron transmission, the energy dependence of σsub(T) has been calculated in the range of 0.014-1 eV. The neutron resonance parameters are presented, which were used in the calculations of the resonance capture integrals Isub(γ): for 168Yb Isub(γ) = (24700 +-3000), for 169Yb Isub(γ) (3860+-500). Average distances between levels anti D and strength functions (S0) are as follows: for 168Yb anti D 9 eV, S0 = 2.4 x 10-4; for 169Yb anti D = 2.2 +-0.5 eV, S0 = (2.1+-0.7)x10-4