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Title: Timing resolution studies of the optical part of the AFP Time-of-flight detector

We present results of the timing performance studies of the optical part and front-end electronics of the time-of-flight subdetector prototype for the ATLAS Forward Proton (AFP) detector obtained during the test campaigns at the CERN-SPS test-beam facility (120 GeV π + particles) in July 2016 and October 2016. The time-of-flight (ToF) detector in conjunction with a 3D silicon pixel tracker will tag and measure protons originating in central exclusive interactions p + p → p + X + p, where the two outgoing protons are scattered in the very forward directions. The ToF is required to reduce so-called pileup backgrounds that arise from multiple proton interactions in the same bunch crossing at high luminosity. The background can fake the signal of interest, and the extra rejection from the ToF allows the proton tagger to operate at the high luminosity required for the measurement of the processes. The prototype detector uses fused silica bars emitting Cherenkov radiation as a relativistic particle passes through them. The emitted Cherenkov photons are detected by a multi-anode micro-channel plate photomultiplier tube (MCP-PMT) and processed by fast electronics.
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  1. Palacky Univ., Olomouc (Czech Republic). RCPTM, Joint Lab.of Optics; Academy of Sciences of the Czech Republic (ASCR), Prague (Czech Republic). Inst. of Physics
  2. National Inst. of Nuclear Physics (INFN), Bologna (Italy); Univ. di Bologna (Italy). Dipartimento di Fisica
  3. Univ. of Texas, Arlington, TX (United States). Dept. of Physics
  4. Inst. for High Energy Physics (IFAE), Barcelona (Spain). Barcelona Inst. of Science and Technology (BIST)
  5. Univ. of Alberta, Edmonton, AB (Canada). Centre for Particle Physics, Dept. of Physics
  6. Univ. of Science and Technology of China, Hefei (China)
  7. SLAC National Accelerator Lab., Menlo Park, CA (United States)
  8. Polish Academy of Sciences (PAS), Krakow (Poland). Henryk Niewodniczanski Inst. of Nuclear Physics
  9. Stony Brook Univ., NY (United States). Dept. of Physics and Astronomy
  10. Charles Univ., Prague (Czech Republic). Inst. of Particle and Nuclear Physics, Faculty of Mathematics and Physics
Publication Date:
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Optics Express
Additional Journal Information:
Journal Volume: 26; Journal Issue: 7; Journal ID: ISSN 1094-4087
Optical Society of America (OSA)
Research Org:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org:
USDOE; MINECO of Spain; Catalan Government; MSMT of Czech Republic
Country of Publication:
United States
OSTI Identifier: