Development of a resonant-cavity-based detector and magnetic field calibration for Cyclotron Radiation Emission Spectroscopy

I will describe progress on a prototype detector for the Project 8 neutrino mass experiment. The Project 8 Collaboration is pursuing a 40-meV/c^2 sensitivity neutrino mass measurement by using Cyclotron Radiation Emission Spectroscopy (CRES) to measure the energies of electrons at the endpoint of the tritium beta decay spectrum with sub-eV resolution. On the path to this goal, we are commissioning the first resonant-cavity-based CRES detector, the Cavity CRES Apparatus. Among its advantages are improvements in energy resolution with an optimized magnetic trap design, higher signal-to-noise ratio due to enhancement of spontaneous emission on resonance with the cavity, as well as hardware for additional calibration handles: an electron gun to provide an energy-tunable monoenergetic electron source, and eventually a cryogenic hyperpolarized ³He NMR system for precise in-situ magnetic field measurements. I will present on the status of and near-term plans for this apparatus.