Speaker
Description
The Time of Propagation (TOP) detector is a novel particle
identification system developed for the barrel region of the Belle II
detector at the SuperKEKB collider at KEK in Tsukuba, Japan. Cherenkov
photons generated by charged particles traversing its quartz radiator
are captured due to total internal reflection. The Cherenkov emission
angle is then reconstructed from the propagation time of individual
photons to the Micro-Channel Plate PMT sensor plane mounted at one end
of the bar. The readout electronics for the 8192 channels of the TOP
system are built around a switched capacitor array waveform sampling
ASIC operating at 2.7 GSa/s. Realtime processing in the front end
electronics extracts the individual timing of detected photons to better
than 100 ps.
This talk presents the current experiences and results from
commissioning, calibration and operation of the Belle II TOP detector in
the first physics runs of the Belle II experiment up until the summer 2020.
