Speaker
Dr
Kurtis Nishimura
(University of Hawaii)
Description
The Belle II detector operating at the SuperKEKB accelerator will utilize the time-of-propagation (TOP) counter as its primary particle identification device in the barrel region. The TOP counter is a compact variant of the detection of internally reflected Cherenkov light (DIRC) technique, which trades the imaging-based performance of a traditional DIRC with fast timing provided by micro-channel plate (MCP) PMTs. In order to read out a large number of such MCP-PMT channels with high precision, an electronics system based on waveform sampling ASICs is being developed. Full waveforms from front-end ASICs are transmitted by fiberoptic links to digital signal processors, which extract the precise charges and times necessary for the final reconstruction. A lower resolution set of timing data is also produced by the front end, collected from all modules, and passed to provide order ~ns event timing to the global trigger. We discuss the general principles of TOP operation and the planned Belle II TOP system, which is expected to provide 4 sigma or better separation of kaons and pions up to momenta of approximately 4 GeV/c.
Author
Dr
Kurtis Nishimura
(University of Hawaii)
