The performance of the jet trigger for the ATLAS detector during 2011 data taking

H. WAHLBERG Y ATLAS COLLABORATION; H. WAHLBERG Y ATLAS COLLABORATION

EUROPEAN PHYSICAL JOURNAL C - PARTICLES AND FIELDS

SPRINGER

Lugar: Berlin; Año: 2016

1434-6044

The performance of the jet trigger for the ATLAS detector at the LHC during the 2011 datataking period is described. During 2011 the LHC provided proton?proton collisions witha centre-of-mass energy of 7 TeV and heavy ion collisions with a 2.76 TeV per nucleon?nucleon collision energy. The ATLAS trigger is a three level system designed to reduce therate of events from the 40 MHz nominal maximum bunch crossing rate to the approximate400 Hz which can be written to offline storage. The ATLAS jet trigger is the primary meansfor the online selection of events containing jets. Events are accepted by the trigger if theycontain one or more jets above some transverse energy threshold. During 2011 data takingthe jet trigger was fully efficient for jets with transverse energy above 25 GeV for triggersseeded randomly at Level 1. For triggers which require a jet to be identified at each of thethree trigger levels, full efficiency is reached for offline jets with transverse energy above60 GeV. Jets reconstructed in the final trigger level and corresponding to offline jets withtransverse energy greater than 60 GeV, are reconstructed with a resolution in transverse en-ergy with respect to offline jets, of better than 4% in the central region and better than 2.5%in the forward direction.