Design, R&D and status of the crystal calorimeter for the Mu2e experiment

Abstract

The Mu2e Experiment at Fermilab will search for coherent, neutrinoless conversion of muons into electrons in the field of a nucleus, with a sensitivity improvement of a factor of 10^4 over previous experiments. Such a charged lepton flavor-violating reaction probes new physics at a scale inaccessible with direct searches at either present or planned high energy colliders. The conversion electron is mono-energetic with an energy slightly below the muon rest mass. If no events are observed in three years of running, Mu2e will set a limit on the ratio between the conversion rate and the capture rate, R_{\mu e}, of < 6 x 10^{-17} (@ 90% CL). In this paper, the physics motivation for Mu2e and the current status of the electromagnetic calorimeter project are briefly presented.