Design and performance of the data acquisition system for the NA61/SHINE experiment at CERN

This paper describes the hardware, firmware and software systems used in data acquisition for the NA61/SHINE experiment at the CERN SPS accelerator. Special emphasis is given to the design parameters of the readout electronics for the 40m3 volume Time Projection Chamber detectors, as these give the largest contribution to event data among all the subdetectors: events consisting of 8 bit ADC values from 256 time slices of 200 k electronic channels are to be read out with ~100 Hz rate. The data acquisition system is organized in “push-data mode”, i.e. local systems transmit data asynchronously. Techniques of solving subevent synchronization are also discussed.