The Performance of Belle II Data Acquisition System in the First Physics Run

The Belle II experiment is a new generation B-factory experiment at KEK in Japan aiming at the search for New Physics in a huge sample of B-meson dacays. The commissioning of the SuperKEKB accelerator was started in 2017 (Phase 1), and then a pilot run with outer detectors was performed in 2018 (Phase 2). From March this year, an operation with the full detector has been started for the physics data taking (Phase 3). The Belle II data acquisiton system (DAQ) is now fully working in the Phase 3 run. The system consists of the trigger timing distribution system, the common readout modules (COPPER) with the unified optical data link to the detector front end, the readout PCs and the network sw…