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Title: The CMS trigger system

Abstract

This paper describes the CMS trigger system and its performance during Run 1 of the LHC. The trigger system consists of two levels designed to select events of potential physics interest from a GHz (MHz) interaction rate of proton-proton (heavy ion) collisions. The first level of the trigger is implemented in hardware, and selects events containing detector signals consistent with an electron, photon, muon, tau lepton, jet, or missing transverse energy. A programmable menu of up to 128 object-based algorithms is used to select events for subsequent processing. The trigger thresholds are adjusted to the LHC instantaneous luminosity during data taking in order to restrict the output rate to 100 kHz, the upper limit imposed by the CMS readout electronics. The second level, implemented in software, further refines the purity of the output stream, selecting an average rate of 400 Hz for offline event storage. The objectives, strategy and performance of the trigger system during the LHC Run 1 are described.

Authors:
 [1]
  1. et al.
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Contributing Org.:
CMS
OSTI Identifier:
1329706
Report Number(s):
FERMILAB-PUB-16-377-CMS; CMS-TRG-12-001; CERN-EP-2016-160; arXiv:1609.02366
Journal ID: ISSN 1748-0221; 1485699
Grant/Contract Number:
AC02-07CH11359
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Instrumentation
Additional Journal Information:
Journal Volume: 12; Journal ID: ISSN 1748-0221
Publisher:
Institute of Physics (IOP)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

Citation Formats

Khachatryan, Vardan. The CMS trigger system. United States: N. p., 2017. Web. doi:10.1088/1748-0221/12/01/P01020.
Khachatryan, Vardan. The CMS trigger system. United States. doi:10.1088/1748-0221/12/01/P01020.
Khachatryan, Vardan. Tue . "The CMS trigger system". United States. doi:10.1088/1748-0221/12/01/P01020. https://www.osti.gov/servlets/purl/1329706.
@article{osti_1329706,
title = {The CMS trigger system},
author = {Khachatryan, Vardan},
abstractNote = {This paper describes the CMS trigger system and its performance during Run 1 of the LHC. The trigger system consists of two levels designed to select events of potential physics interest from a GHz (MHz) interaction rate of proton-proton (heavy ion) collisions. The first level of the trigger is implemented in hardware, and selects events containing detector signals consistent with an electron, photon, muon, tau lepton, jet, or missing transverse energy. A programmable menu of up to 128 object-based algorithms is used to select events for subsequent processing. The trigger thresholds are adjusted to the LHC instantaneous luminosity during data taking in order to restrict the output rate to 100 kHz, the upper limit imposed by the CMS readout electronics. The second level, implemented in software, further refines the purity of the output stream, selecting an average rate of 400 Hz for offline event storage. The objectives, strategy and performance of the trigger system during the LHC Run 1 are described.},
doi = {10.1088/1748-0221/12/01/P01020},
journal = {Journal of Instrumentation},
number = ,
volume = 12,
place = {United States},
year = {Tue Jan 24 00:00:00 EST 2017},
month = {Tue Jan 24 00:00:00 EST 2017}
}

Journal Article:
Free Publicly Available Full Text
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Citation Metrics:
Cited by: 26works
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