TRB Collaboration

A prototype of the A1 Neutron Detector comprising 24 plastic scintillator bars and four plastic scintillator veto panels was tested in the Three-Spectrometer-Hall at the Mainz Microtron (MAMI). Each scintillator bar or veto strip is instrumented with two PMTs enabling position reconstruction along the bar axis via timing between the two PMTs. Furthermore, Time-over-Threshold (ToT) information is used to suppress background from charged particles. In addition, very high rates per scintillator (~MHz) are expected for the final experiment. The PMT signals are send to NINO frontend boards which, in turn, are read out by a TRB system. Using the CBM-MBS external trigger module the A1 trigger number is also included in the data stream. All of these requirements were successfully tested during the recent test beam time in Mainz.