Supperlattice Doped APDs for Improved UV Sensitivity in Scintillator Calorimetry

One of the proposed next generation Intensity Frontier experiments is Mu2e. Mu2e will directly probe the Intensity Frontier as well as aid research on the Energy and Cosmic frontiers with precision measurements required to characterize the properties and interactions of new particles discovered at the Intensity Frontier. In order to reach its science goals, detector upgrades are required. A key apparatus of Mu2e is its calorimeter, which will need faster and more UV sensitive photodetectors for reading out the UV emission from fast scintillators located in the calorimeter disk. RMDs silicon avalanche photodiodes (APDs) have been identified as a potential photodetector for the Mu2e calorimeter, however, this will require an epitaxial modification (superlattice doping) of the APD to increase detector UV sensitivity and speed of response. In the proposed effort our optimization will involve exploiting an epitaxial fabrication process, which has been used successfully with silicon CCDs that will improve APD UV sensitivity and temporal properties for the detection of UV scintillation emission. Commercial Applications and Other Benefits: Medical imaging modalities such as SPECT and PET, which use blue-UV emitting scintillators, would directly benefit from advances in the proposed technology. Likewise, hand held instruments and vehicle portals used for monitoring nuclear material movement using UV emitting scintillation crystals would benefit as well. Ultraviolet and optical astronomy would be another potential application.