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Title: The Belle II imaging Time-of-Propagation (iTOP) detector

High precision flavor physics measurements are an essential complement to the direct searches for new physics at the LHC ATLAS and CMS experiments. We will perform these measurements using the upgraded Belle II detector that will take data at the SuperKEKB accelerator. With 40x the luminosity of KEKB, the detector systems must operate efficiently at much higher rates than the original Belle detector. A central element of the upgrade is the barrel particle identification system. Belle II has built and installed an imaging-Time-of-Propagation (iTOP) detector. The iTOP uses quartz optics as Cherenkov radiators. The photons are transported down the quartz bars via total internal reflection with a spherical mirror at the forward end to reflect photons to the backward end where they are imaged onto an array of segmented Micro-Channel Plate Photo-Multiplier Tubes (MCP-PMTs). The system is read out using giga-samples per second waveform sampling Application-Specific Integrated Circuits (ASICs). Furthermore, we used the combined timing and spatial distribution of the photons for each event to determine particle species. This paper provides an overview of the iTOP system.
  1. Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 0168-9002; PII: S0168900217302280
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment
Additional Journal Information:
Journal Volume: 876; Journal ID: ISSN 0168-9002
Research Org:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org:
Contributing Orgs:
Belle II Barrel Particle Identification Group
Country of Publication:
United States
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; particle identification; ring-imaging Cherenkov; RICH; time-of-propagation; Belle II
OSTI Identifier: