학술논문
The LHCb Trigger and its Performance in 2011
Document Type
Working Paper
Author
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.; Dijkstra, H.; Drancourt, C.; Dzhelyadin, R.; Frank, M.; Gandelman, M.; Gaspar, C.; Gligorov, V. V.; Göbel, C.; GranadoCardoso, L. A.; Guz, Yu.; Haen, C.; He, J.; vanHerwijnen, E.; Hulsbergen, W.; Jacobsson, R.; Jost, B.; Karbach, T. M.; Kerzel, U.; Koppenburg, P.; Krocker, G.; Langenbruch, C.; Lax, I.; LeGac, R.; Lefèvre, R.; Lefrançois, J.; Leroy, O.; LiGioi, L.; Liu, G.; Machefert, F.; Machikhiliyan, I. V.; Magne, M.; Mancinelli, G.; Marconi, U.; MartínSánchez, A.; Minard, M. -N.; Monteil, S.; Neufeld, N.; Niess, V.; Oggero, S.; Pérez-CaleroYzquierdo, A.; Perret, P.; Perrin-Terrin, M.; Pietrzyk, B.; PuigNavarro, A.; Raven, G.; Robbe, P.; Ruiz, H.; Schune, M. -H.; Schwemmer, R.; Serrano, J.; Shapoval, I.; Skwarnicki, T.; SouzaDePaula, B.; Spradlin, P.; Stahl, S.; Subbiah, V. K.; T'Jampens, S.; Teubert, F.; Thomas, C.; Vesterinen, M.; Williams, M.; Witek, M.; Zvyagin, A.
Source
Subject
Language
Abstract
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.