Quality Evaluation Electronics for CBM-TOF Super Module

The time-of-flight (TOF) system in the compressed Baryonic matter (CBM) experiment is comprised of super modules and used for charged hadron identification. Each super module contains several multigap resistive plate chambers (MRPCs) for high-precision time measurements. The quality of each super module should be evaluated to ensure that the detectors achieve the targeted performance. In this paper, the quality evaluation electronics for super modules based on the peripheral component interconnect eXtensions for instrumentation platform is proposed. The discriminated MRPC signals are digitized by the time-to-digital converter (TDC). Then, the digitized time data from a super module are aggregated at the TDC readout motherboard and are transmitted to the data readout modules (DRMs) via optical links. Finally, the DRMs relay the digitized data to the data acquisition system through the Gigabit Ethernet ports in parallel. The laboratory test results indicate that the quality evaluation electronics achieve a time resolution better than 20 ps. The initial cosmic ray tests with the MRPC detectors have also been conducted to confirm the performance of the quality evaluation system. Based on the results, the evaluation system can subsequently be used for quality evaluation of the CBM-TOF super module.