Naslov
Energy calibration and resolution of the CMS electromagnetic calorimeter in pp collisions at sqrt(s) = 7 TeV

Autori
Chatrchyan, S. ; ... ; Godinović, Nikola ; Lelas, Damir ; Pleština, Roko ; Polić, Dunja ; Puljak, Ivica ; Antunović, Željko ; Kovač, Marko ; Brigljević, Vuko ; Đurić, Senka ; Kadija, Krešo ; Luetić, Jelena ; Morović, Srećko ; Mekterović, Darko ; Tikvica, Lucija ; ... ; Swanson, J.

Izvornik
Journal of Instrumentation (1748-0221) 8 (2013); P09009-1

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
Gamma detectors (scintillators; CZT; HPG; HgI etc); Calorimeters; Large detector systems for particle and astroparticle physi

Sažetak
The energy calibration and resolution of the electromagnetic calorimeter (ECAL) of the CMS detector have been determined using proton-proton collision data from LHC operation in 2010 and 2011 at a centre-of-mass energy of sqrt(s)=7 TeV with integrated luminosities of about 5 inverse femtobarns. Crucial aspects of detector operation, such as the environmental stability, alignment, and synchronization, are presented. The in-situ calibration procedures are discussed in detail and include the maintenance of the calibration in the challenging radiation environment inside the CMS detector. The energy resolution for electrons from Z-boson decays is better than 2% in the central region of the ECAL barrel (for pseudorapidity abs(eta)<0.8) and is 2-5% elsewhere. The derived energy resolution for photons from 125 GeV Higgs boson decays varies across the barrel from 1.1% to 2.6% and from 2.2% to 5% in the endcaps. The calibration of the absolute energy is determined from Z to e+e- decays to a precision of 0.4% in the barrel and 0.8% in the endcaps.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

POVEZANOST RADA