Scalable low-frequency microwave cavities for the Project 8 neutrino mass experiment

Project 8 is a next-generation experiment aiming to directly measure the neutrino mass with a targeted sensitivity of 40 meV. Utilizing the tritium endpoint method and Cyclotron Radiation Emission Spectroscopy (CRES), the previous phase of Project 8 has placed an upper limit on this mass of 155 eV (90% CL). The next development phase will demonstrate CRES in a large source volume, culminating in a pilot-scale CRES experiment with sub-eV sensitivity. In this talk, I will introduce the cavity-based CRES concept, in which we propose to use large scale cylindrical microwave cavities operating at low frequencies (150 MHz - 1 GHz) as a means of signal extraction. I will present recent progress in the experimental design of these cavities, and highlight the next steps for a 40 meV sensitivity neutrino mass measurement.