Indirect Measurements of Radiative Capture Reactions on Lanthanides

Radiative capture and photodisintegration reactions of lanthanides involving neutrons are of particular importance to nuclear applications. Experimental constraints make direct measurements of these cross sections nontrivial. Therefore, it is essential to have a reliable method for predicting (γ,n) and (n,γ) cross sections. One alternative to direct a measurement in the mass and energy regions of interest is the surrogate method, which provides an indirect measurement for radiative capture reactions using a more feasible experiment that generates the desired compound nucleus. Surrogate measurements for ^145,146Sm(n,γ) and ^159,160Dy(n,γ) have been conducted using the LLNL Hyperion array at Texas A&M Univ. Cyclotron Institute. Hyperion is comprised of 12 HPGe clover detectors coupled to a segmented silicon telescope. Particle-γ coincidence data for (p,d) and (p,t) reactions on self-supporting ¹⁴⁸Sm and ¹⁶²Dy targets have been analyzed in collaboration with LLNL to extract nuclear structure information and γ-decay probabilities. Preliminary results will be presented.