Affordable Access

Publisher Website

The LHCb Trigger and its Performance in 2011

  • Aaij, R.
  • Albrecht, J.
  • Alessio, F.
  • Amato, S.
  • Aslanides, E.
  • Belyaev, I.
  • vanBeuzekom, M.
  • Bonaccorsi, E.
  • Bonnefoy, R.
  • Brarda, L.
  • Callot, O.
  • Cattaneo, M.
  • Chanal, H.
  • Chebbi, M.
  • CidVidal, X.
  • Clemencic, M.
  • Closier, J.
  • Coco, V.
  • Cogan, J.
  • Deschamps, O.
  • And 63 more
Publication Date
Apr 03, 2013
Submission Date
Nov 13, 2012
DOI: 10.1088/1748-0221/8/04/P04022
External links


This paper presents the design of the LHCb trigger and its performance on data taken at the LHC in 2011. A principal goal of LHCb is to perform flavour physics measurements, and the trigger is designed to distinguish charm and beauty decays from the light quark background. Using a combination of lepton identification and measurements of the particles' transverse momenta the trigger selects particles originating from charm and beauty hadrons, which typically fly a finite distance before decaying. The trigger reduces the roughly 11\,MHz of bunch-bunch crossings that contain at least one inelastic $pp$ interaction to 3\,kHz. This reduction takes place in two stages; the first stage is implemented in hardware and the second stage is a software application that runs on a large computer farm. A data-driven method is used to evaluate the performance of the trigger on several charm and beauty decay modes.

Report this publication


Seen <100 times