Neutron Inelastic Scattering Processes as Background for Double-Beta Decay Experiments

We investigate several Pb(n, nγ) and Ge(n, nγ) reactions. We measure γ-ray production from Pb(n, nγ) reactions that can be a significant background for double-beta decay experiments which use lead as a massive inner shield. Particularly worrisome for Ge-based double-beta decay experiments are the 2041-keV and 3062-keV γ rays produced via Pb(n, nγ). The former is very close to the Ge double-beta decay endpoint energy and the latter has a double escape peak energy near the endpoint. Excitation γ-ray lines from Ge(n, nγ) reactions are also observed. We consider the contribution of such backgrounds and their impact on the sensitivity of next-generation searches for neutrinoless double-beta decay using enriched germanium detectors.