E. Craig Dukes (University of Virginia)
The Mu2e experiment is designed to search for the charged-lepton-flavor-violating process, $\mu^-$ to a $e^-$, with unprecedented sensitivity. The single 105-MeV electron that results from this process can be mimicked by electrons produced by cosmic-ray muons traversing the detector. An active veto detector surrounding the apparatus is used to detect incoming cosmic-ray muons. To reduce the backgrounds to the required level it must have an efficiency of about 99.99% as well as excellent hermeticity. The detector consists of four layers of scintillator counters, each with two embedded wavelength-shifting fibers, whose light is detected by silicon photomultipliers. The design and expected performance of the cosmic ray veto detector will be described.
E. Craig Dukes (University of Virginia) Ralf Ehrlich (University of Virginia)