| Popis: |
The Belle II experiment operates at the SuperKEKB $e^+ e^-$ energy-asymmetric collider on or near the $\Upsilon(4S)$ resonance energy. The Belle II experiment has completed the ``Phase 2'' run, in which the Belle II operation without the vertex detector system has been tested. The main focus of the Phase~2 run is on the search for new physics related with dark sector, axion-like particles, etc. with an intermediate luminosity on the way to reach the challenging target. To accomplish these physics goals of Phase~2, a new trigger menu for the single photon and low multiplicity events is essential. With the luminosity design goal, it is crucial to cope with a high trigger rate for data acquisition (DAQ). In this presentation, we describe the DAQ system of Belle II, focusing on the successful commissioning in Phase 2 and the performance of the system. |
