Fast Data-Driven Readout System for the Wide Aperture Silicon Tracking System of the BM@N Experiment

The major upgrade of the BM@N experiment for the heavy ion program is a new hybrid tracking system. It consists of seven planes of GEM detectors and four silicon tracking stations based on the modules with double-sided microstrip silicon sensors of CBM type. The BM@N silicon tracking system (STS) will conceptually inherit the data acquisition system (DAQ) from the CBM silicon tracker currently in development for FAIR. This is an entirely data driven acquisition system relying on purely self-triggering readout channels, which will also be adopted for the operation with BM@N trigger. The core components of the readout chain are front-end boards (FEB), GBTxEmu board and GBTxEmu readout interface (GERI) board. The front-end board is an integrated part of the STS module. The main components of FEB are eight STS-XYTER ASICs which are needed for the readout of one side of the silicon sensor. The GBTxEmu board comprises an FPGA which emulates functionality of the CERN GBTx ASIC and provides a bidirectional optical link between front-end electronics and data processing boards in the computer nodes. The GERI board implements the following functionalities: concentrating and preprocessing of the data stream, filtering of the data according to the BM@N trigger signals and providing an interface for the detector control system (DCS) to configure readout electronics.