Resonant Cavity Development for the Project 8 Neutrino Mass Experiment

Project 8 is a next generation experiment aiming to directly measure the neutrino mass using the tritium endpoint method with a targeted sensitivity of 40~meV. Having established a new measurement technique, Cyclotron Radiation Electron Spectroscopy (CRES), the next development phase will demonstrate CRES on a large source volume, culminating in a pilot-scale CRES experiment with atomic tritium. One possibility involves a mode-filtered, cylindrical, resonant cavity in which cyclotron radiation signals from magnetically trapped beta electrons only couple to the lowest eigenmode, maximizing effective volume and minimizing signal complexity. We will show studies of mode-filtered resonant cavities and progress in the design of a small scale cavity CRES proof-of-concept apparatus, which will demonstrate scalability of CRES to large volumes.