Cyclotron Radiation Emission Spectroscopy for Neutrino Mass Measurement

Cyclotron Radiation Emission Spectroscopy (CRES) is a novel technique for measuring the energy of single electrons by detecting the cyclotron radiation they emit in a magnetic field. The Project 8 Collaboration has pioneered the CRES technique to measure the energy spectrum of beta electrons emitted in the decay of tritium, with the goal of improving sensitivity to the neutrino mass. Precise measurement of the region near the endpoint of the beta spectrum is currently the most sensitive technique to directly measure the neutrino mass. The Project 8 Collaboration plans to use CRES to overcome statistical and systematic challenges inherent in current beta spectroscopy experiments. Following the collaboration's first upper limit on the neutrino mass from its Phase II experiment, we have been developing technology to achieve a final sensitivity goal of 0.04 eV. The newest prototype, the Cavity CRES Apparatus (CCA), will be the first CRES detector with resonant cavity geometry, enabling scalability, improved energy resolution, and event-by-event magnetic field corrections. I will discuss advantages of the CRES technique, the current status of the CCA, and the technology roadmap for future experimental phases.