Atomic lithium R&D as a pathfinder toward magnetic evaporative tritium cooling for Project 8*

Project 8 aims to probe the absolute neutrino mass to a 40meV scale by studying the end point of tritium beta decay spectrum via Cyclotron Radiation Emission Spectroscopy (CRES). A high flux atomic tritium beam will improve the energy resolution by eliminating the molecular vibration states and is a crucial requirement to reach the desired precision. However, techniques for cooling large atomic fluxes to the mK temperatures needed for trapping in a CRES experiment are yet to be demonstrated. In parallel to the ongoing work on atomic hydrogen manipulation, Project 8 is developing a Magnetic Evaporative Cooling Beamline for lithium as a proxy to tritium. This talk will focus on the recent advancements in the lithium cooling apparatus and application of fluorescence spectroscopy for spatial tomography and thermometry to provide beam diagnostics.