Design and Performance of the Data Acquisition System for the NA61/SHINE Experiment at CERN

Abstract

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 40m^3 volume Time Projection Chamber detectors, as these give the largest contribution to event data among all the subdetectors: events consisting of 8bit ADC values from 256 timeslices of 200k electronic channels are to be read out with ~100Hz 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.