Electron reconstruction in CMS |
| |
Authors: | S Baffioni C Charlot F Ferri D Futyan P Meridiani I Puljak C Rovelli R Salerno Y Sirois |
| |
Institution: | (1) Laboratoire Leprince-Ringuet, Ecole Polytechnique and IN2P3-CNRS, 91128 Palaiseau Cedex, France;(2) Università degli Studi Milano-Bicocca and INFN-Sezione di Milano, 20216 Milano, Italy;(3) University of California, Riverside, CA 92521, USA;(4) Dipartimento di Fisica and INFN-Sezione di Roma, Università “La Sapienza”, 00185 Roma, Italy;(5) FESB, Technical University of Split, 21000 Split, Croatia |
| |
Abstract: | The reconstruction of the energy and momentum of isolated electrons in CMS combining tracking and electromagnetic calorimetry
information is described. The emphasis is put on primary electrons with transverse momentum below 50 GeV/c. The energy deposited
in the electromagnetic calorimeter is measured in clusters of clusters (superclusters) which collect bremsstrahlung photons
emitted along the electron trajectory in the tracker volume. The electron tracks are built from seeds in the pixel detector
found via a cluster-driven pixel hit matching algorithm, followed by a reconstruction of trajectories in the silicon strip
tracker with a Gaussian sum filter. Electrons are classified using observables sensitive to the pattern of bremsstrahlung
emission and electromagnetic showering in the tracker material. Energy scale corrections depending on the electron class are
applied to the supercluster and estimates of associated errors are obtained. The electron energy is deduced from a weighted
combination of the corrected supercluster energy and tracker momentum measurements. The electron direction is that of the
reconstructed electron track at interaction vertex. The pre-selection of isolated electron candidates for physics analysis
is described. Class-dependent observables combining tracking and calorimetry information are discussed for electron identification. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|