The Mu3e experiment is a proposed experiment to search for the lepton flavour violating decay mu+→ e+e-e+. In the standard model, this decay is highly suppressed with a branching ratio << 10-50. However, many theories beyond the standard model predict significantly enhanced decay rates. An observation of this decay would hence be a clear sign of new physics.
The goal of the Mu3e experiment is to reach a sensitivity of one in 1016 muons, which is four orders of magnitude better than previous experiments. In order to reach this sensitivity, a detector with an excellent momentum-, vertex- and time resolution is necessary in order to sufficiently reduce the background.
In our group, we are developing a detector system to precisely measure the arrival time of the electrons in order to detect coincident signals of three electrons. The detector consists out of small scintillating tiles, which are read out by Silicon Photomultipliers (SiPMs). The challenge is to achieve an exellent time resolution better than 100 ps, and an efficiency close to 100% at a hit rate of up to a few MHz.
In order to meet these requirements, we are doing simulation studies, measure and optimize the sciltillator-SiPM system and developing a first prototype of the detector.
A key component of the detector is the readout electronics for the SiPMs. Here, we are developing an ASIC which provides a very good time resolution as well as high rate capability, and thus can fullfil the stringent requirements necessary to achieve the desired detector performance.