The ${}^{136} \mathrm{Xe} (n, n' \gamma ) {}^{136} \mathrm{Xe}$ Reaction at 8 MeV

An experiment was performed to look for $\gamma$-ray lines due to neutron inelastic scattering on ${}^{136}$Xe in order to identify potential background lines in the region of interest for neutrinoless double-beta decay searches like EXO and KamLAND-Zen. One clear line at 2414.7 keV was found which KamLAND-Zen cannot distinguish from the predicted neutrinoless double-beta decay signal at 2458 keV. In addition, a \textsc{Geant4} computer simulation of the 60 \% HPGe detectors used in our experiment was developed to model the detectors' efficiencies at various energies and distances from a radiation source, and we began to extend this simulation to model our entire experiment.